X-ray Photoelectron Spectroscopy as a tool to investigate silane-based coatings for the protection of outdoor bronze: The role of alloying elements

Publication date: 1 March 2018
Source:Applied Surface Science, Volume 433
Author(s): G. Masi, A. Balbo, J. Esvan, C. Monticelli, J. Avila, L. Robbiola, E. Bernardi, M.C. Bignozzi, M.C. Asensio, C. Martini, C. Chiavari
Application of a protective coating is the most widely used conservation treatment for outdoor bronzes (cast Cu-Sn-Zn-Pb-Sb alloys). However, improving coating protectiveness requires detailed knowledge of the coating/substrate chemical bonding. This is particularly the case for 3-mercapto-propyl-trimethoxy-silane (PropS-SH) applied on bronze, exhibiting a good protective behaviour in outdoor simulated conditions. The present work deals with X-Ray Photoelectron Spectroscopy (XPS) and Electron Microscopy (FEG-SEM+FIB (Focused Ion Beam)) characterization of a thin PropS-SH film on bronze. In particular, in order to better understand the influence of alloying elements on coating performance, PropS-SH was studied first on pure Cu and Sn substrates then on bronzes with increasing alloy additions: Cu8Sn as well as a quinary Cu-Sn-Zn-Pb-Sb bronze. Moreover, considering the real application of this coating on historical bronze substrates, previously artificially aged ("patinated") bronze samples were prepared and a comparison between bare and "patinated" quinary bronzes was performed. In the case of coated quinary bronze, the free surface of samples was analysed by High Resolution Photoelectron Spectroscopy using Synchrotron Radiation (HR-SRPES) at ANTARES (Synchrotron SOLEIL), which offers a higher energy and lateral resolution. By compiling complementary spectroscopic and imaging information, a deeper insight into the interactions between the protective coating and the bronze substrate was achieved.

Graphical abstract

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Electron emission enhancement of long hybrid emitters prepared using ZnO nanowires decorated with Zn nanoflakes

Publication date: 1 March 2018
Source:Applied Surface Science, Volume 433
Author(s): Su-Hua Yang, Nai-Chieh Hsu
Hybrid emitters consisting of ZnO nanowires decorated with Zn nanoflakes were prepared for electron emission applications. The ZnO nuclei, having a pyramidal shape, were deposited on the ZnO:Al buffer layer, which offered surface protrusions for vertical nanowire growth. The Zn hexagonal nanoflakes, having thicknesses of 15–20nm, were decorated to increase the conductivity and number of emission sites of the ZnO nanowires. The field enhancement factor increased from 8623 to 18108 and the work function was reduced from 5.3 to 3.35eV after decorating the nanowires with Zn nanoflakes. A low turn-on field of 0.65MV/m and high current density of 1.46mA/cm² were obtained. The current density variation measured at 350V was less than 23% over a measurement time of 180min.



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Intra-regional classification of grape seeds produced in Mendoza province (Argentina) by multi-elemental analysis and chemometrics tools

Publication date: 1 March 2018
Source:Food Chemistry, Volume 242
Author(s): Brenda V. Canizo, Leticia B. Escudero, María B. Pérez, Roberto G. Pellerano, Rodolfo G. Wuilloud
The feasibility of the application of chemometric techniques associated with multi-element analysis for the classification of grape seeds according to their provenance vineyard soil was investigated. Grape seed samples from different localities of Mendoza province (Argentina) were evaluated. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of twenty-nine elements (Ag, As, Ce, Co, Cs, Cu, Eu, Fe, Ga, Gd, La, Lu, Mn, Mo, Nb, Nd, Ni, Pr, Rb, Sm, Te, Ti, Tl, Tm, U, V, Y, Zn and Zr). Once the analytical data were collected, supervised pattern recognition techniques such as linear discriminant analysis (LDA), partial least square discriminant analysis (PLS-DA), k-nearest neighbors (k-NN), support vector machine (SVM) and Random Forest (RF) were applied to construct classification/discrimination rules. The results indicated that nonlinear methods, RF and SVM, perform best with up to 98% and 93% accuracy rate, respectively, and therefore are excellent tools for classification of grapes.



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Enhancement of the optical absorption of carbon group elements doped ZnS in the visible light range

Publication date: March 2018
Source:Renewable Energy, Volume 117
Author(s): Hai-Cai Huang, Chuan-Lu Yang, Mei-Shan Wang, Xiao-Guang Ma
Although the pristine ZnS can perform photocatalytic hydrogen production from water splitting, the reaction can not be driven by the visible light because of its wide energy band gap. Therefore, ZnS doped with carbon group elements (C, Si, Ge, Sn, Pb) has been investigated by using first-principles density functional theory calculations to understand the feasibility of the reaction driven by solar energy. All the geometrical structures are fully optimized. The electronic and optical properties of these structures have been calculated with the meta-GGA + MBJ method and with projector augmented wave potential. The results show that all the doped structures have low formation energies, implying that the synthesis of the doped structures is not difficult in energy. Moreover, the absorptions of the doped structures in the visible light range are significantly enhanced, but their energy levels are still suitable for water splitting to generate hydrogen, which means that carbon group elements doped ZnS structures are promising candidate materials for water splitting driven by visible light.

Graphical abstract

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From interpenetration to non-interpenetration: A series of self-assemblies predominated by reaction conditions

Publication date: 15 February 2018
Source:Journal of Molecular Structure, Volume 1154
Author(s): Yan Wang, Yang Song, Lu Liu, Jun Chen, Peng Wang, Yong Zhao
Four Cd/Zn coordination frameworks, namely, [Cd(TPBA-4)(NO3)2]·2DMF·1.22H2O (1), [Cd(TPBA-4)(NO3)2]·H2O (2), [Cd(TPBA-4)(NO3)2]·2.2Me2CO·0.32H2O (3), and [Zn(TPBA-4)(NO3)2]·1.5Me2CO (4) were synthesized by the reaction of N′,N″,N‴-tris(pyrid-4-ylmethyl)-1,3,5-benzenetricarboxamide (TPBA-4) with the corresponding d¹⁰ metal salts. X-ray diffraction analysis revealed that complex 1 was of two-fold interpenetrated 2D network with interlocked cage-like motif. The structure of 2 is three-fold interpenetrated 2D honeycomb network. On the other hand, the 3 and 4 are isomorphous and isostructural, and have different 2D networks compared to 1 and 2. Thus the series of complexes have the same metal atoms and ligands but different structures. In complex 1, 2, 3, and 4, the flexible TPBA-4 ligands are versatile and adopt different conformations according to different reaction conditions, which predominates the final structures of these complexes. The physical properties of these complexes were also investigated.

Graphical abstract

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Pronation and supination analysis based on biomechanical signals from Parkinson’s disease patients

Publication date: Available online 16 October 2017
Source:Artificial Intelligence in Medicine
Author(s): Alejandro Garza-Rodríguez, Luis Pastor Sánchez-Fernández, Luis Alejandro Sánchez-Pérez, Christopher Ornelas-Vences, Mariane Ehrenberg-Inzunza
In this work, a fuzzy inference model to evaluate hands pronation/supination exercises during the MDS-UPDRS motor examination is proposed to analyze different extracted features from the bio-mechanical signals acquired from patients with Parkinson's disease (PD) in different stages of severity. Expert examiners perform visual assessments to evaluate several aspects of the disease. Some previous work on this subject does not contemplate the MDS-UPDRS guidelines. The method proposed in this work quantifies the biomechanical features examiners evaluate. The extracted characteristics are used as inputs of a fuzzy inference model to perform an assessment strictly attached to the MDS-UPDRS. The acquired signals are processed by techniques of digital signal processing and statistical analysis. The experiments were performed in collaboration with clinicians and patients from different PD associations and institutions. In total, 210 different measurements of patients with PD, plus 20 different measurements of healthy control subjects were performed. With objective values rated by several feature extraction procedures there is the possibility to track down the disease evolution in a patient, and to detect subtle changes in the patient's condition.



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Chaotic genetic algorithm and Adaboost ensemble metamodeling approach for optimum resource planning in emergency departments

Publication date: Available online 18 October 2017
Source:Artificial Intelligence in Medicine
Author(s): Milad Yousefi, Moslem Yousefi, Ricardo Poley Martins Ferreira, Joong Hoon Kim, Flavio S. Fogliatto
Long length of stay and overcrowding in emergency departments (EDs) are two common problems in the healthcare industry. To decrease the average length of stay (ALOS) and tackle overcrowding, numerous resources, including the number of doctors, nurses and receptionists need to be adjusted, while a number of constraints are to be considered at the same time. In this study, an efficient method based on agent-based simulation, machine learning and the genetic algorithm (GA) is presented to determine optimum resource allocation in emergency departments. GA can effectively explore the entire domain of all 19 variables and identify the optimum resource allocation through evolution and mimicking the survival of the fittest concept. A chaotic mutation operator is used in this study to boost GA performance. A model of the system needs to be run several thousand times through the GA evolution process to evaluate each solution, hence the process is computationally expensive. To overcome this drawback, a robust metamodel is initially constructed based on an agent-based system simulation. The simulation exhibits ED performance with various resource allocations and trains the metamodel. The metamodel is created with an ensemble of the adaptive neuro-fuzzy inference system (ANFIS), feedforward neural network (FFNN) and recurrent neural network (RNN) using the adaptive boosting (AdaBoost) ensemble algorithm. The proposed GA-based optimization approach is tested in a public ED, and it is shown to decrease the ALOS in this ED case study by 14%. Additionally, the proposed metamodel shows a 26.6% improvement compared to the average results of ANFIS, FFNN and RNN in terms of mean absolute percentage error (MAPE).



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Native Vessel CERAB Re-establishes Aorto-iliac Flow Following Occluded Aortobifemoral Bypass

Publication date: Available online 18 October 2017
Source:European Journal of Vascular and Endovascular Surgery
Author(s): Arindam Chaudhuri, Ramita Dey




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Enzyme prodrug therapies and therapeutic enzymes

Publication date: Available online 18 October 2017
Source:Advanced Drug Delivery Reviews
Author(s): Brigitte Städler, Alexander N. Zelikin




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Life-cycle impacts of shower water waste heat recovery: case study of an installation at a university sport facility in the UK

Abstract

Recovering heat from waste water discharged from showers to preheat the incoming cold water has been promoted as a cost-effective, energy-efficient, and low-carbon design option which has been included in the UK's Standard Assessment Procedure (SAP) for demonstrating compliance with the Building Regulation for dwellings. Incentivized by its carbon cost-effectiveness, waste water heat exchangers (WWHX) have been selected and incorporated in a newly constructed Sports Pavilion at the University of Brighton in the UK. This £2-m sports development serving several football fields was completed in August 2015 providing eight water- and energy-efficient shower rooms for students, staff, and external organizations. Six of the shower rooms are located on the ground floor and two on the first floor, each fitted with five or six thermostatically controlled shower units. Inline type of WWHX were installed, each consisted of a copper pipe section wound by an external coil of smaller copper pipe through which the cold water would be warmed before entering the shower mixers. Using the installation at Sport Pavilion as the case study, this research aims to evaluate the environmental and financial sustainability of a vertical waste heat recovery device, over a life cycle of 50 years, with comparison to the normal use of a PVC-u pipe. A heat transfer mathematical model representing the system has been developed to inform the development of the methodology for measuring the in-situ thermal performance of individual and multiple use of showers in each changing room. Adopting a system thinking modeling technique, a quasi-dynamic simulation computer model was established enabling the prediction of annual energy consumptions under different shower usage profiles. Data based on the process map and inventory of a functional unit of WWHX were applied to a proprietary assessment software to establish the relevant outputs for the life-cycle environmental impact assessment. Life-cycle cost models were developed and industry price book data were applied. The results indicated that the seasonal thermal effectiveness was over 50% enabling significant energy savings through heat recovery that led to short carbon payback time of less than 2 years to compensate for the additional greenhouse gas emissions associated with the WWHX. However, the life-cycle cost of the WWHX is much higher than using the PVC pipe, even with significant heat recovered under heavy usage, highlighting the need to adopt more economic configurations, such as combining waste water through fewer units, in order to maximize the return on investment and improve the financial viability.

http://ift.tt/2gQm6o6

Fungicidal activity of slow-release P(3HB)/TEB formulations in wheat plant communities infected by Fusarium moniliforme

Abstract

Fungicidal activity of experimental tebuconazole (TEB) formulations was investigated in laboratory soil ecosystems in wheat plant communities infected by Fusarium moniliforme. TEB was embedded in the matrix of poly-3-hydroxybutyrate, shaped as films and microgranules. These formulations were buried in the soil with wheat plants, and their efficacy was compared with that of commercial formulation Raxil and with the effect of pre-sowing treatment of seeds. In the experiment with the initially infected seeds and a relatively low level of natural soil infection caused by Fusarium fungi, the effects of the experimental P(3HB)/TEB formulations and Raxil were comparable. However, when the level of soil infection was increased by adding F. moniliforme spores, P(3HB)/TEB granules and films reduced the total counts of fungi and the abundance of F. moniliforme more effectively than Raxil. Seed treatment or soil treatment with Raxil solution showed an increase in the percentage of rot-damaged roots in the later stages of the experiment. In the early stage (between days 10 and 20), the percentage of rot-damaged roots in the soil with TEB embedded in the slowly degraded P(3HB) matrix was similar to that in the soil with Raxil. However, the efficacy of P(3HB)/TEB formulations lasted longer, and in later stages (between days 20 and 30), the percentage of rot-damaged roots in that group did not grow. In experiments with different TEB formulations and, hence, different fungicidal activities, the increase in plant biomass was 15–17 to 40–60% higher than in the groups where TEB was applied by using conventional techniques.

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Treatment of keloid scars using light-, laser- and energy-based devices: a contemporary review of the literature

Abstract

Keloid scars are common and have a predilection for young, ethnic skin often with a family history. Keloids can be painful and pruritic and cause significant emotional distress when particularly visible or prominent. In this article, we review the evidence underlying the use of laser- and energy-based devices for treatment of keloid scars, either as monotherapy or in conjunction with other therapies such as corticosteroids, surgery and silicone gel in the treatment of keloid scars.

http://ift.tt/2giXsLU

Release and kinetics of arsenic and plumbum in the Songhua River surficial sediments

Abstract

To estimate the pollution of As and Pb in the Songhua River which flows through the major rice-producing regions in China, the present study investigated the level and release of As and Pb in surficial sediments which collected from nine sites in Songhua River (M₁–M₉). The concentration of As and Pb was ranged as follows: As = 3.104~15.01 μg/g, Pb = 20.10~37.42 μg/g; the average concentration: As = 6.466 ± 3.077 μg/g, Pb = 28.88 ± 5.077 μg/g. By analysis vertically, the average concentration of As was 5.166 ± 1.496 μg/g in the upstream, 5.815 ± 1.793 μg/g in the midstream, and 9.716 ± 4.977 μg/g in the downstream. The average concentration of Pb was 27.83 ± 4.552 μg/g in the upstream, 28.66 ± 6.333 μg/g in the midstream, and 30.99 ± 4.837 μg/g in the downstream. It indicated that the concentration of As and Pb increased gradually from upstream to downstream. As existed mainly as insoluble state and Pb existed mainly as sulfide and organic combining state in surficial sediments, and the species of As and Pb could transform with the change of the circumstance. The release of quantity of As was higher than Pb. The pH of 6 was not conducive to the release of As and Pb. When the temperature was 35 and 6 °C, the release of As and Pb in surficial sediments were restrained, respectively. Fumaric acid and citric acid played an important role in promoting the release of As, but not conducive to Pb. Furthermore, the reasonable aeration rate was beneficial to the release process of As and Pb in surficial sediment. By kinetic analysis, the Elovich equation (Ct = 84.931–8.952lnt) could be used to describe the dynamic process of the release of As in a relatively short time. The Elovich equation (C _t  = 2.724 + 1.3724lnt) and double constant rate equation (lnC _T  = 1.4646 + 0.1522lnT) could well describe the dynamics process of the release of Pb.

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The role of personality in body image dissatisfaction and disordered eating: discrepancies between men and women

Abstract

Background

Body image and disordered eating research has focused mostly on the female experience. The present study examined gender differences in the relationship between personality, disordered eating, and body image dissatisfaction.

Methods

Participants were 238 female and 85 male undergraduates (M _age = 20.52 years, SD = 4.22) at a Canadian university. Materials included a battery of self-report questionnaires pertaining to personality, body image, and disordered eating.

Results

As expected, females reported more body dissatisfaction and disordered eating than males. Personality factors were found to be significantly related to the experience of body dissatisfaction in both genders. Further, several personality traits significantly contributed to the prediction of male (high Neuroticism, low Conscientiousness) and female (high Neuroticism) body dissatisfaction beyond the influence of body mass index (BMI). Interestingly, and contrary to findings with female participants, personality traits were not significantly related to disordered eating scores in men. Among women, disordered eating scores were significantly predicted by high Neuroticism and Extraversion, and low Conscientiousness.

Conclusions

Although the relationship between disordered eating, body image dissatisfaction, and personality is well-documented in females, this relation may differ for males. The focus on male body image has been increasing in Western society; exploring how males view their bodies may be beneficial to researchers and clinicians alike.

http://ift.tt/2yrfxlK

Norman Sharpless sworn in as director of the National Cancer Institute

Norman E. "Ned" Sharpless, M.D., becomes the 15th director of the National Cancer Institute (NCI). He comes to NCI from the University of North Carolina School of Medicine, where he was director of the Lineberger Comprehensive Cancer Center.

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Priming Immunotherapy in Advanced Disease With Radiation

Conditions:   Non-small Cell Lung Cancer;   Squamous Cell Carcinoma of the Head and Neck
Interventions:   Drug: Immune checkpoint inhibitor;   Radiation: Radiation Therapy
Sponsor:   John L. Villano, MD, PhD
Not yet recruiting

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Neoadjuvant Treatment Associated With Maintenance Therapy by Anti-PD1 Immunotherapy in Patients With Resectable Head and Neck Mucosal Melanoma

Condition:   Resectable Head and Neck Mucosal Melanomas
Interventions:   Drug: Pembrolizumab;   Procedure: Surgery;   Radiation: IMRT
Sponsor:   Gustave Roussy, Cancer Campus, Grand Paris
Not yet recruiting

http://ift.tt/2yyRNvt

Editorial Board

Publication date: December 2017
Source:Journal of Human Evolution, Volume 113





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The revised stratigraphy of the hominin-bearing site of Kromdraai (Gauteng, South Africa) and associated perspectives

Publication date: January 2018
Source:Journal of Human Evolution, Volume 114
Author(s): Laurent Bruxelles, Richard Maire, Amélie Beaudet, Raymond Couzens, Francis Duranthon, Jean-Baptiste Fourvel, Dominic Stratford, Francis Thackeray, José Braga
The Plio-Pleistocene site of Kromdraai B (South Africa), located in the 'Cradle of Humankind' area recognized in 1998 by UNESCO, corresponds to a Plio-Pleistocene paleokarst that yielded the holotype of Paranthropus robustus in 1938. Since that discovery, thousands of faunal remains (including additional hominin fossils) and stone tools have been discovered there. Here we report a new study of the karstic fillings of the hominin-bearing site of Kromdraai, which enables a reappraisal of its stratigraphy. The deposits correspond to a talus cone fed by one entrance that progressively filled the cave, which is larger than previously thought. Based on the stratigraphy, geometry, and composition of the breccias, we propose a new and more complex evolution of the cave. Four main periods of cave filling can be distinguished, corresponding to four kinds of deposits directly related to the evolution of the cave, and which show the progressive dismantling of the cavity and increasing influence from the landscape surface. This filling regime, however, is not continuous, and major unconformities identified may cover long periods of time. Despite this, an overall coherence emerges from the history of the cave and its deposits, the paleontological and paleoanthropological data, and the archaeological studies. It is now possible to reinterpret the discoveries from earlier investigations and place them in their general stratigraphic context. Our study shows that Kromdraai spans a much longer time span of hominin evolution than previously proposed. In addition, the breccias from the central part of the Kromdraai B site provide some of the first data on at least part of a hitherto unrecorded period at Sterkfontein: a phase marked by a major erosional unconformity between Members 4 and 5, before 2.20 Ma.



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Editorial Board

Publication date: November 2017
Source:Journal of Human Evolution, Volume 112





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Association between coal consumption and urbanization in a coal-based region: a multivariate path analysis

Abstract

This study examines causal relationship between urbanization and coal consumption. By taking Shanxi Province, China, as a typical case area, a multivariate path analysis model is used to seek for the key driving factors of coal consumption throughout its urbanization during the period of 1978 to 2014. The result indicates that the key factors are urban household disposable income and residential area per capita, which are closely related to urban construction and household lifestyle. It is expected that the study may inform better policies on coal consumption reduction and energy structure improvement.

http://ift.tt/2gNy7ub

Cosmetics, Vol. 4, Pages 41: Efficiency of Nisin as Preservative in Cosmetics and Topical Products

Cosmetics, Vol. 4, Pages 41: Efficiency of Nisin as Preservative in Cosmetics and Topical Products

Cosmetics doi: 10.3390/cosmetics4040041

Authors: Elisabete Maurício Catarina Rosado Maria Duarte Joana Verissimo Sara Bom Laura Vasconcelos

Nisin is a bacteriocin synthesized by certain species of Lactococcus lactis, that has been recently employed as a preservative in the food industry. Taking into account its potential as a natural preservative, its applicability in cosmetics and topical products was probed, aiming to replace or reduce the use of synthetic preservatives currently used in these products. In vitro susceptibility tests were performed using the plate diffusion method and the "Challenge Test". The action of nisin was tested when applied alone and in synergy with ethylenediaminetetraacetic acid tetrasodium salt (EDTA) and similar synthetic preservatives, Abiol® (INCI-Imidazolidinyl urea) and Microcare PM2 (Phenoxyethanol, Ethylparaben, Methylparaben). The results of this study demonstrate that nisin is effective in inhibiting gram-positive microorganisms Staphylococcus aureus and Bacillus sp. However, for other tested microorganisms, only the combination of nisin, EDTA and synthetic preservatives, respectively at 125 ppm/0.1/0.35%, showed antimicrobial activity in compliance with criterion A from ISO 11930. With this study, it is concluded that nisin can be a viable alternative when associated with other preservatives, reducing the use of higher doses of chemical/synthetic preservatives that are often associated with sensitivity and allergic reactions.

http://ift.tt/2ytS0y1

Harnessing the cross-talk between tumor cells and tumor-associated macrophages with a nano-drug for modulation of glioblastoma immune microenvironment

Publication date: Available online 16 October 2017
Source:Journal of Controlled Release
Author(s): Tong-Fei Li, Ke Li, Chao Wang, Xin Liu, Yu Wen, Yong-Hong Xu, Quan Zhang, Qiu-Ya Zhao, Ming Shao, Yan-Ze Li, Min Han, Naoki Komatsu, Li Zhao, Xiao Chen
Glioblastoma (GBM) is the most frequent and malignant brain tumor with a high mortality rate. The presence of a large population of macrophages (Mφ) in the tumor microenvironment is a prominent feature of GBM and these so-called tumor-associated Mφ (TAM) closely interact with the GBM cells to promote the survival, progression and therapy resistance of the GBM. Various therapeutic strategies have been devised either targeting the GBM cells or the TAM but few have addressed the cross-talks between the two cell populations. The present study was carried out to explore the possibility of exploiting the cross-talks between the GBM cells (GC) and TAM for modulation of the GBM microenvironment through using Nano-DOX, a drug composite based on nanodiamonds bearing doxorubicin. In the in vitro work on human cell models, Nano-DOX-loaded TAM were first shown to be viable and able to infiltrate three-dimensional GC spheroids and release cargo drug therein. GC were then demonstrated to encourage Nano-DOX-loaded TAM to unload Nano-DOX back into GC which consequently emitted damage-associated molecular patterns (DAMPs) that are powerful immunostimulatory agents as well as indicators of cell damage. Nano-DOX was next proven to be a more potent inducer of GC DAMPs emission than doxorubicin. As a result, Nano-DOX-damaged GC exhibited an enhanced ability to attract both TAM and Nano-DOX-loaded TAM. Most remarkably, Nano-DOX-damaged GC reprogrammed the TAM from a pro-GBM phenotype to an anti-GBM phenotype that suppressed GC growth. Finally, the in vivo relevance of the in vitro findings was tested in animal study. Mice bearing orthotopic human GBM xenografts were intravenously injected with Nano-DOX-loaded mouse TAM which were found releasing drug in the GBM xenografts 24h after injection. GC damage was evidenced by the induction of DAMPs emission within the xenografts and a shift of TAM phenotype was detected as well. Taken together, our results demonstrate a novel way with therapeutic potential to harness the cross-talk between GBM cells and TAM for modulation of the tumor immune microenvironment.

Graphical abstract

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QPRTase modified N-doped carbon quantum dots: A fluorescent bioprobe for selective detection of neurotoxin quinolinic acid in human serum

Publication date: 15 March 2018
Source:Biosensors and Bioelectronics, Volume 101
Author(s): Ranjana Singh, Sunayana Kashayap, Vimal Singh, Arvind M. Kayastha, Hirdyesh Mishra, Preeti Suman Saxena, Anchal Srivastava, Ranjan K. Singh
Highly fluorescent nitrogen doped carbon quantum dots (NCQDs) were synthesized using microwave assisted green method. It was characterized by Transmission Electron Microscopy (TEM), FTIR, UV–Visible absorption and Photoluminiscence (PL) techniques. The NCQDs were immobilized with an enzyme named quinolinate phoshphoribosyl transferase (QPRTase). The NCQDs immobilized by QPRTase was used as a fluorescent bioprobe for the selective detection of endogenous neurotoxin quinolinic acid (QA) whose elevated level in serum is marker of many neurological disorders such as Alzheimer's, Huntington's and HIV associated dementia (HAD) as well as deficiency of vitamin B6. Steady state PL studies were carried out to measure the PL response of the fabricated fluorescent bioprobe as a function of QA concentrations in human serum samples. This probe was found applicable in linear range [3.22–51µM] with the limit of detection ~ 6.51µM. It has desirable sensitivity ~ (0.02340±0.0001) µM⁻¹, excellent stability for ~ 7 weeks and good reproducibility. The similar response of this fluorescent bioprobe for QA detection in triple distilled water and human serum shows that it is unaffected by variation in media. Hence, this fluorescent bioprobe can be employed for QA detection in serum sample for the early detection of many diseases.

Graphical abstract

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A shape-code nanoplasmonic biosensor for multiplex detection of Alzheimer's disease biomarkers

Publication date: 15 March 2018
Source:Biosensors and Bioelectronics, Volume 101
Author(s): Hanbi Kim, Jong Uk Lee, Sojin Song, Soohyun Kim, Sang Jun Sim
Alzheimer's disease (AD) is a neurodegenerative disease associated with the loss of nerve cells in the brain. The disease is affected by multifactorial pathways and leads to changes in related biomolecular levels as AD progresses. Therefore, AD should be diagnosed with combined detection of several lesions to improve accuracy. Amyloid beta 1–40, 1–42 and τ (tau) protein are milestones in AD pathology and can be used as main screening and diagnostic target markers. Here, we suggest a highly selective biosensor for detection of AD core biomarkers on one platform through distinct localized surface plasmon resonance (LSPR) depending on gold nanoparticles shapes, called a shape-code biosensor. This plasmonic sensor consists of only gold nanoparticles and antibody, but does not need additory methods for precise separation from multifarious samples and identification of markers. Under physiological condition, we determined a detection limit of 34.9fM for amyloid beta (Aβ) 1–40, 26fM for Aβ 1–42 and 23.6fM for τ protein corresponding to the ~ 1, ~ 2.23 and ~ 3.12nm of Rayleigh scattering peak shift on shape-code plasmon system for each biomarker in mimicked blood. This is the first highly sensitive shape-code biosensor to detect AD biomarkers which can be used to diagnose AD easily in the future.



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Scholar : These new articles for Pediatric Hematology and Oncology are available online

The online platform for Taylor & Francis Online content New for Pediatric Hematology and Oncology and online now on Taylor & Francis Online: Original Articles Treatment and survival of childhood neuroblastoma: Evidence from a population-based study in the United States Dairmuid Coughlan, Matthew Gianferante, Charles F Lynch, Jennifer L Stevens & Linda C Harlan Pages: 1-11 | DOI: 10.1080/08880018.2017.1373315 Combination of clofarabine, cyclophosphamide, and etoposide for relapsed or refractory childhood and adolescent acute myeloid leukemia Yoav Messinger , Jessica Boklan, John Goldberg, Steven G. DuBois, Javier Oesterheld, Oussama Abla, Alissa Martin, Joanna Weinstein & Nobuko Hijiya Pages: 1-12 | DOI: 10.1080/08880018.2017.1360970 Outcome of acute lymphoblastic leukemia in children with down syndrome—Polish pediatric leukemia and lymphoma study group report Joanna Zawitkowska PhD, Teresa Odój PhD, Katarzyna Drabko PhD, Agnieszka Zaucha-Prażmo PhD, Julia Rudnicka MD, Michał Romiszewski PhD, Michał Matysiak, Kinga Kwiecińska PhD, Magdalena Ćwiklińska PhD, Walentyna Balwierz, Joanna Owoc-Lempach PhD, Katarzyna Derwich PhD, Jacek Wachowiak, Maciej Niedźwiecki PhD, Elżbieta Adamkiewicz- Drożyńska, Joanna Trelińska PhD, Wojciech Młynarski, Andrzej Kołtan PhD, Mariusz Wysocki, Renata Tomaszewska PhD, Tomasz Szczepański, Marcin Płonowski PhD, Maryna Krawczuk-Rybak, Tomasz Ociepa PhD, Tomasz Urasiński, Agnieszka Mizia-Malarz PhD, Grażyna Sobol-Milejska PhD, Grażyna Karolczyk PhD & Jerzy Kowalczyk Pages: 1-7 | DOI: 10.1080/08880018.2017.1363837 Pediatric NUT-midline carcinoma: Therapeutic success employing a sarcoma based multimodal approach Simone Storck MD, Alyssa L. Kennedy MD, PhD, Karen J. Marcus MD, Lisa Teot MD, Jennifer Vaughn MD, Astrid K. Gnekow MD, Bruno Märkl MD, Ivo Leuschner MD, Steven G. DuBois MD, Christopher A. French MD & Michael C. Frühwald MD, PhD Pages: 1-7 | DOI: 10.1080/08880018.2017.1363839 FAK-Src-paxillin system expression and disease outcome in human neuroblastoma Panagiotis Kratimenos , Ioannis Koutroulis, Vasiliki Syriopoulou, Christina Michailidi, Maria Delivoria-Papadopoulos, Jerzy Klijanienko & Stamatios Theocharis Pages: 1-10 | DOI: 10.1080/08880018.2017.1360969 Report Dramatic clinical and radiographic response to BRAF inhibition in a patient with progressive disseminated optic pathway glioma refractory to MEK inhibition Abhishek Bavle, Jeremy Jones, Frank Y. Lin, Amy Malphrus, Adekunle Adesina & Jack Su Pages: 1-6 | DOI: 10.1080/08880018.2017.1360971 To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

In vitro bond strength of an epoxy resin-based root canal sealer to root dentin irradiated with high-power lasers and adhesive interface analyses

Abstract

The aim of this study was to evaluate in vitro the influence of high-power lasers (Nd:YAG and diode 980 nm) associated with mineral coal as fotopotencializer on bond strength of an epoxy resin-based root canal sealer to root dentin, using the pushout test, and on the dentin/filling material interface, using confocal laser microscopy. For this purposes, 50 canines were instrumented with Mtwo rotary system up to #50.04 instrument and randomly assigned to five groups (n = 10): group I—control EDTAC; group II—EDTAC and Nd:YAG laser; group III—EDTAC and diode laser 980 nm; group IV—EDTAC, Nd:YAG laser and mineral coal 5 g/100 mL; and group V—EDTAC, diode laser 980 nm and mineral coal 5 g/100 mL. All data were analyzed by ANOVA (at 5% significance level) following the Kruskal-Wallis, Dunn and Tukey tests. The group I increased more bond strength of the sealer to root dentin that treated with only EDTAC 17% (17.21 ± 21.75 MPa), similar to the group II (12.21 ± 18.20 MPa) and group IV (14.92 ± 28.06 MPa), both treated with Nd:YAG laser, with the exception of group IV, which was added to mineral coal. The group V (8.75 ± 13.42 MPa) had similar results to the groups II and IV, but the same similarity were found when compared with group III (7.11 + 11.28 MPa), with lower results. Regarding the root thirds, the apical third (23.27 ± 29.21 MPa) presented a statistically higher value on bond strength than the cervical third (5.92 ± 5.33 MPa) and middle third (6.93 ± 7, 11 MPa) (p > 0.05). Group II (86.27 μm) showed the highest tags penetration values, with a statistically difference to the group III (51.57 μm), IV (36.77 μm) and V (32.37 μm) (p < 0.05). Group I (71.63 μm) was statistically similar to groups II and III (p > 0.05). Group IV had the lowest values and was statistically similarity to groups III and V (p > 0.05). It was concluded that the treatment with Nd:YAG laser provides better results than the diode 980 nm laser, except when was added mineral coal. The control and diode 980 nm laser groups presented less adhesive failures and more mists failures than the other groups. Both lasers did not interfere negatively compared to the control group.

http://ift.tt/2kXwBKJ

Scholar : These new articles for Computer-Aided Design and Applications are available online

The online platform for Taylor & Francis Online content New for Computer-Aided Design and Applications and online now on Taylor & Francis Online: Original Articles Computer-aided design tool for GT ventilation system ductworks Rocco Furferi , Lapo Governi , Francesca Uccheddu & Yary Volpe Pages: 1-10 | DOI: 10.1080/16864360.2017.1375666 Browse articles in this special issue on: 'Advancements in Civil and Structural Engineering' To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Characterization of carbonaceous fractions in PM 2.5 and PM 10 over a typical industrial city in central China

Abstract

Aerosol samples of PM_2.5 and PM₁₀ were collected every 6 days from March 2012 to February 2013 in Huangshi, a typical industrial city in central China, to investigate the characteristics, relationships, and sources of carbonaceous species. The PM_2.5 and PM₁₀ samples were analyzed for organic carbon (OC), elemental carbon (EC), char, and soot using the thermal/optical reflectance (TOR) method following the IMPROVE_A protocol. PM_2.5 and PM₁₀ concentrations ranged from 29.37 to 501.43 μg m⁻³ and from 50.42 to 330.07 μg m⁻³, with average levels of 104.90 and 151.23 μg m⁻³, respectively. The 24-h average level of PM_2.5 was about three times the US EPA standard of 35 μg m⁻³, and significantly exceeds the Class II National Air Quality Standard of China of 75 μg m⁻³. The seasonal cycles of PM mass and OC concentrations were higher during winter than in summer. EC and char concentrations were generally highest during winter but lowest in spring, while higher soot concentrations occurred in summer. This seasonal variation could be attributed to different seasonal meteorological conditions and changes in source contributions. Strong correlations between OC and EC were found for both PM_2.5 and PM₁₀ in winter and fall, while char and soot showed a moderate correlation in summer and winter. The average OC/EC ratios were 5.11 and 4.46 for PM_2.5 and PM₁₀, respectively, with individual OC/EC ratios nearly always exceeding 2.0. Higher char/soot ratios during the four seasons indicated that coal combustion and biomass burning were the major sources for carbonaceous aerosol in Huangshi. Contrary to expectations, secondary organic carbon (SOC) which is estimated using the EC tracer method exhibited spring maximum and summer minimum, suggesting that photochemical activity is not a leading factor in the formation of secondary organic aerosols in the study area. The contribution of SOC to OC concentration for PM_2.5 and PM₁₀ were 47.33 and 45.38%, respectively, implying that SOC was an important component of OC mass. The serious air pollution in haze-fog episode was strongly correlated with the emissions of pollutants from biomass burning and the meteorological conditions.

http://ift.tt/2yRPxAN

Chemical elements as fingerprints of geographical origin in cultivars of Vitis vinifera L. raised on the same SO4 rootstock

Abstract

The uptake of major and trace elements in grapevine (Vitis vinifera L.) can be influenced by soil, climate, geographic origin, and rootstock type. Rootstocks were mainly selected to resist phylloxera and for specific tolerance to lime, mineral uptake, drought, and salinity. The relationship among concentrations of major, trace, and rare earth elements was studied in soil and leaves from two Italian grapevine cultivars, "Cabernet Sauvignon" and "Corvina," employed to produce renowned controlled designation of origin (DOC) wines. The cultivars were raised on the same rootstock SO4 in two different areas of the Veneto Region (Northern Italy). The elements were studied by X-ray fluorescence and inductively coupled plasma mass spectrometry, and data were elaborated by non-parametric tests and multivariate linear discrimination analysis. The related index of bioaccumulation was calculated to define the specific assimilation of the elements from soil to leaves. A statistically significant correspondence between soil and leaf samples was observed for Mg, Sm, V, and Zr. The results allowed to discriminate soil and leaf samples of the two cultivars according to geographical provenance, possibly providing geochemical markers (fingerprints) useful against fraudulent use of DOC wine labels.

http://ift.tt/2hOIkpZ

Strategies of heavy metal uptake by three Armeria species growing on different geological substrates in Serbia

Abstract

This study surveyed three species of the genus Armeria Willd. from five ultramafic outcrops, two non-ultramafic (schist) soils, and one tailing heap of an abandoned iron-copper mine from Serbia. Similarities and differences among the three Armeria species growing on different geological substrates in the ability to control uptake and translocate nine metals were examined. Chemical characteristics of the soil and plant samples (concentrations of P₂O_5, K₂O, Ca, Fe, Mn, Ni, Zn, Cu, Cr, Co, Cd, and Pb) are presented. In order to assess accumulative potential of these three Armeria species, biological concentration, accumulation, as well as translocation factors were used. Three investigated Armeria species growing on eight different localities showed large differences in heavy metal uptake, translocation, and accumulation. The differences were present among the plant samples of the same species and even more among three different Armeria species and were primarily the result of the different contents of available heavy metals in the investigated soils. Additionally, differences might be the consequence of diverse responses and possible presence of supplementary resistance mechanisms in the plants from the ultramafic soils. None of the three Armeria species showed shoot hyperaccumulative potential for any of the investigated heavy metals and they could be considered as root accumulators, considering their potential to accumulate medium to large amounts of Zn (BCF up to 134), Cr (BCF up to 148), and Cd (BCF up to 9) in their roots.

http://ift.tt/2ySAWVG

Lead in roadway dusts from different functional areas in a typical valley city, NW China: contamination and exposure risk

Abstract

Lead contamination and exposure risk assessment in roadway dusts from four different functional areas in a typical valley city in northwest China (Xi'an) were conducted in this study. A total of 130 roadway dust samples from park area (PA), traffic area (TA), educational area (EA), and residential area (RA) were collected and Pb concentrations in the samples were determined by using XRF (X-ray fluorescence). Geo-accumulation index (I _geo) and enrichment factor (EF) were applied to assess Pb contamination level and the hazard indexes (HI) of Pb were calculated to evaluate the exposure risks to children and adults. The results showed that roadway dusts from all four functional areas had elevated Pb concentrations and pollution characteristics of Pb were discrepant in different functional areas. The mean concentration of Pb in roadway dusts from PA, TA, EA, and RA was 147.4, 74.8, 119.6, and 161.0 mg kg⁻¹, respectively. The I _geo and EF of Pb were mostly 1–3 and 2–20, which indicated moderate to high Pb contamination in roadway dusts. High contamination level of Pb in RA and EA should receive priority for prevention and control. Exposure risk assessment of Pb from roadway dusts was mainly in the acceptable range, but the potential risk of Pb exposure to children should be continuously concerned.

http://ift.tt/2hOIcH1

Scholar : These new articles for Activities, Adaptation & Aging are available online

The online platform for Taylor & Francis Online content New for Activities, Adaptation & Aging and online now on Taylor & Francis Online: Original Articles Exploring the Impact of a New Intervention to Increase Participation of Frail Older Adults in Meaningful Leisure Activities V. Provencher, H. Carbonneau, M. Levasseur, V. Poulin, J. Filiatrault, D. Giroux & M. Filion-Trudeau Pages: 1-18 | DOI: 10.1080/01924788.2017.1376176 Routledge Psychology 2017 sponsor of BPS #PsychCrunch podcasts. Access 25 journal articles: http://bit.ly/psychcrunch2017 To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Scholar : Dramatherapy, Volume 38, Issue 2-3, July - November 2017 is now available online on Taylor & Francis Online

The online platform for Taylor & Francis Online content Dramatherapy, Volume 38, Issue 2-3, July - November 2017 is now available online on Taylor & Francis Online. This new issue contains the following articles: Editorials Editorial Anna Seymour Pages: 77-79 | DOI: 10.1080/02630672.2017.1361172 Original Articles Behold the tree: an exploration of the social integration of boys on the autistic spectrum in a mainstream primary school through a dramatherapy intervention Nicky Dyer Pages: 80-93 | DOI: 10.1080/02630672.2017.1329845 'The memory of the tree': a new theatrical model of genogram Fabrizio Fiaschini Pages: 94-105 | DOI: 10.1080/02630672.2017.1329449 Creating the role: how dramatherapy can assist in re/creating an identity with recovering addicts Tanya Newman Pages: 106-123 | DOI: 10.1080/02630672.2017.1340492 Interview with Alida Gersie Anna Seymour & Alida Gersie Pages: 124-132 | DOI: 10.1080/02630672.2017.1351210 Clinical Comment Dramatherapy and psychodrama with Looked-After children and young people Joan Moore, Madeline Andersen-Warren & Kate Kirk Pages: 133-147 | DOI: 10.1080/02630672.2017.1351782 Book Review Dramatherapy and autism Roland Javanaud Pages: 148-151 | DOI: 10.1080/02630672.2017.1351795 Book Reviews The positive side of negative emotions Mary Booker Pages: 151-152 | DOI: 10.1080/02630672.2017.1351212 The adopter's handbook on therapy; getting the best for your child Katharine McAuley Pages: 153-154 | DOI: 10.1080/02630672.2017.1351213 Anna Halprin: dance – process – form Cathy Goodwin Pages: 154-155 | DOI: 10.1080/02630672.2017.1351209 Applied theatre: international case studies and challenges for practice, 2nd edition Lou Ghirlando Pages: 155-157 | DOI: 10.1080/02630672.2017.1351211 Editorial Board Editorial Board Pages: ebi-ebi | DOI: 10.1080/02630672.2017.1375797 Routledge Psychology 2017 sponsor of BPS #PsychCrunch podcasts. Access 25 journal articles: http://bit.ly/psychcrunch2017 To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Early identification of MCI converting to AD: a FDG PET study

Abstract

Purpose

Mild cognitive impairment (MCI) is a transitional pathological stage between normal ageing (NA) and Alzheimer's disease (AD). Although subjects with MCI show a decline at different rates, some individuals remain stable or even show an improvement in their cognitive level after some years. We assessed the accuracy of FDG PET in discriminating MCI patients who converted to AD from those who did not.

Methods

FDG PET was performed in 42 NA subjects, 27 MCI patients who had not converted to AD at 5 years (nc-MCI; mean follow-up time 7.5 ± 1.5 years), and 95 MCI patients who converted to AD within 5 years (MCI-AD; mean conversion time 1.8 ± 1.1 years). Relative FDG uptake values in 26 meta-volumes of interest were submitted to ANCOVA and support vector machine analyses to evaluate regional differences and discrimination accuracy.

Results

The MCI-AD group showed significantly lower FDG uptake values in the temporoparietal cortex than the other two groups. FDG uptake values in the nc-MCI group were similar to those in the NA group. Support vector machine analysis discriminated nc-MCI from MCI-AD patients with an accuracy of 89% (AUC 0.91), correctly detecting 93% of the nc-MCI patients.

Conclusion

In MCI patients not converting to AD within a minimum follow-up time of 5 years and MCI patients converting within 5 years, baseline FDG PET and volume-based analysis identified those who converted with an accuracy of 89%. However, further analysis is needed in patients with amnestic MCI who convert to a dementia other than AD.

http://ift.tt/2zxEDNF

Predictive value of 18 F-FDG PET/CT in adults with T-cell lymphoblastic lymphoma: post hoc analysis of results from the GRAALL-LYSA LLO3 trial

Abstract

Purpose

We examined whether FDG PET can be used to predict outcome in patients with lymphoblastic lymphoma (LL).

Methods

This was a retrospective post hoc analysis of data from the GRAAL-LYSA LL03 trial, in which the treatment of LL using an adapted paediatric-like acute lymphoblastic leukaemia protocol was evaluated. PET data acquired at baseline and after induction were analysed. Maximum standardized uptake values (SUV_max), total metabolic tumour volume and total lesion glycolysis were measured at baseline. The relative changes in SUV_max from baseline (ΔSUV_max) and the Deauville score were determined after induction.

Results

The population analysed comprised 36 patients with T-type LL. SUV_max using a cut-off value of ≤8.76 vs. >8.76 was predictive of 3-year event-free survival (31.6% vs. 80.4%; p = 0.013) and overall survival (35.0% vs. 83.7%; p = 0.028). ΔSUV_max using a cut-off value of ≤80% vs. >80% tended also to be predictive of 3-year event-free survival (40.0% vs. 76.0%; p = 0.054) and overall survival (49.2% vs. 85.6%; p = 0.085). Total metabolic tumour volume, baseline total lesion glycolysis and response according to the Deauville score were not predictive of outcome.

Conclusions

A low initial SUV_max was predictive of worse outcomes in our series of patients with T-type LL. Although relatively few patients were included, the study also suggested that ΔSUV_max may be useful for predicting therapeutic efficacy.

http://ift.tt/2zhsb3C

Heterogeneity index evaluated by slope of linear regression on 18 F-FDG PET/CT as a prognostic marker for predicting tumor recurrence in pancreatic ductal adenocarcinoma

Abstract

Purpose

¹⁸F-Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) has been investigated as a method to predict pancreatic cancer recurrence after pancreatic surgery. We evaluated the recently introduced heterogeneity indices of ¹⁸F-FDG PET/CT used for predicting pancreatic cancer recurrence after surgery and compared them with current clinicopathologic and ¹⁸F-FDG PET/CT parameters.

Methods

A total of 93 pancreatic ductal adenocarcinoma patients (M:F = 60:33, mean age = 64.2 ± 9.1 years) who underwent preoperative ¹⁸F-FDG PET/CT following pancreatic surgery were retrospectively enrolled. The standardized uptake values (SUVs) and tumor-to-background ratios (TBR) were measured on each ¹⁸F-FDG PET/CT, as metabolic parameters. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were examined as volumetric parameters. The coefficient of variance (heterogeneity index-1; SUVmean divided by the standard deviation) and linear regression slopes (heterogeneity index-2) of the MTV, according to SUV thresholds of 2.0, 2.5 and 3.0, were evaluated as heterogeneity indices. Predictive values of clinicopathologic and ¹⁸F-FDG PET/CT parameters and heterogeneity indices were compared in terms of pancreatic cancer recurrence.

Results

Seventy patients (75.3%) showed recurrence after pancreatic cancer surgery (mean recurrence = 9.4 ± 8.4 months). Comparing the recurrence and no recurrence patients, all of the ¹⁸F-FDG PET/CT parameters and heterogeneity indices demonstrated significant differences. In univariate Cox-regression analyses, MTV (P = 0.013), TLG (P = 0.007), and heterogeneity index-2 (P = 0.027) were significant. Among the clinicopathologic parameters, CA19–9 (P = 0.025) and venous invasion (P = 0.002) were selected as significant parameters. In multivariate Cox-regression analyses, MTV (P = 0.005), TLG (P = 0.004), and heterogeneity index-2 (P = 0.016) with venous invasion (P < 0.001, 0.001, and 0.001, respectively) demonstrated significant results.

Conclusions

The heterogeneity index obtained using the linear regression slope, could be an effective predictor of pancreatic cancer recurrence after pancreatic cancer surgery, in addition to ¹⁸F-FDG PET/CT volumetric parameters and clinicopathologic parameters.

http://ift.tt/2zyuf8b

Impact of partial-volume correction in oncological PET studies: a systematic review and meta-analysis

Abstract

Purpose

Positron-emission tomography can be useful in oncology for diagnosis, (re)staging, determining prognosis, and response assessment. However, partial-volume effects hamper accurate quantification of lesions <2–3× the PET system's spatial resolution, and the clinical impact of this is not evident. This systematic review provides an up-to-date overview of studies investigating the impact of partial-volume correction (PVC) in oncological PET studies.

Methods

We searched in PubMed and Embase databases according to the PRISMA statement, including studies from inception till May 9, 2016. Two reviewers independently screened all abstracts and eligible full-text articles and performed quality assessment according to QUADAS-2 and QUIPS criteria. For a set of similar diagnostic studies, we statistically pooled the results using bivariate meta-regression.

Results

Thirty-one studies were eligible for inclusion. Overall, study quality was good. For diagnosis and nodal staging, PVC yielded a strong trend of increased sensitivity at expense of specificity. Meta-analysis of six studies investigating diagnosis of pulmonary nodules (679 lesions) showed no significant change in diagnostic accuracy after PVC (p = 0.222). Prognostication was not improved for non-small cell lung cancer and esophageal cancer, whereas it did improve for head and neck cancer. Response assessment was not improved by PVC for (locally advanced) breast cancer or rectal cancer, and it worsened in metastatic colorectal cancer.

Conclusions

The accumulated evidence to date does not support routine application of PVC in standard clinical PET practice. Consensus on the preferred PVC methodology in oncological PET should be reached. Partial-volume-corrected data should be used as adjuncts to, but not yet replacement for, uncorrected data.

http://ift.tt/2zhs3RG

Visualization of HER2-specific breast cancer intratumoral heterogeneity using 64 Cu-DOTA-trastuzumab PET

http://ift.tt/2zy1rwD

Interim FDG-PET in lymphoma, a questionable practice in hematology

http://ift.tt/2ziKFAP

Measurement uncertainty and clinical impact of target-to-background ratios derived by interim FDG-PET/CT in Hodgkin lymphoma: reply to Laffon and Martan

http://ift.tt/2zvNcZ7

Bone SPECT/CT in the postoperative spine: a focus on spinal fusion

Abstract

Low back pain is a global problem affecting one in 10 people. The management of low back pain varies from conservative to more invasive methods with a spectacular increase in the number of patients undergoing spinal fusion surgery during the last decade. Conventional radiological and radionuclide studies are often used in the assessment of persistent or recurring pain after spinal surgery with several advantages and limitations related to each technique. This article reviews the key contribution of integrated bone SPECT/CT in evaluating patients with persistent or recurring pain after spinal surgery, focusing on spinal fusion. Current literature supports the use of bone SPECT/CT as an adjunct imaging modality and problem-solving tool in evaluating patients with suspicion of pseudarthrosis, adjacent segment degeneration, and hardware failure. The role of bone SPECT/CT in post-operative orthopaedic scenarios is evolving, and this review highlights the need for further research on the role of bone SPECT/CT in these patients.

http://ift.tt/2ziKyVV

A rare case of thymoma first detected on gallium-68 PSMA PET/CT

http://ift.tt/2zx32CX

Poor predictive value of positive interim FDG-PET/CT in primary mediastinal large B-cell lymphoma

Abstract

Purpose

Though commonly used to assess response to therapy, the prognostic value of interim FDG-PET/CT in Primary Mediastinal Large B-cell Lymphoma (PMBCL) is unclear.

Methods

We conducted a retrospective study on 36 consecutive patients treated at our institution for a PMBCL between 2006 and 2014. All patients with a positive interim FDG-PET/CT had undergone histological restaging consisting either in a surgical debulking of the residual lesion (15 patients) or a CT-guided core needle biopsy (two patients). All FDG-PET/CT were secondarily reviewed according to the more recent Deauville criteria.

Results

Interim FDG-PET/CT was considered positive in 17/36 patients using visual evaluation. Among these patients, 14 had a Deauville score of 4. Histological restaging was negative in all but one case, showing inflammation and/or fibrosis. After a median follow-up of 48.5 months, a total of five patients have relapsed, two patients in the positive FDG-PET/CT group, and three patients in the negative FDG-PET/CT group, respectively.

Conclusions

These data indicate that a positive interim FDG-PET/CT does not reflect persistence of active disease in the vast majority of PMBCL cases. The relapse rate appears similar regardless of interim FDG-PET/CT results and interpretation criteria. This suggests that interim FDG-PET/CT has a poor positive predictive value, thus kt should be used with caution in PMBCL.

http://ift.tt/2ziKsO3

Single high dose versus repeated bone-targeted radionuclide therapy

http://ift.tt/2zyudNB

About the specificity of radiotracers for prostate cancer

http://ift.tt/2zhrCXy

Quantification: there is more to worry about than good scanner hardware and reliable calibration

http://ift.tt/2zx30ej

18 F-Florbetaben PET beta-amyloid binding expressed in Centiloids

Abstract

Purpose

The Centiloid (CL) method enables quantitative values from Aβ-amyloid (Aβ) imaging to be expressed in a universal unit providing pathological, diagnostic and prognostic thresholds in clinical practice and research and allowing integration of multiple tracers and methods. The method was developed for ¹¹C-PiB scans with zero CL set as the average in young normal subjects and 100 CL the average in subjects with mild Alzheimer's disease (AD). The method allows derivation of equations to convert the uptake value of any tracer into the same standard CL units but first requires head-to-head comparison with ¹¹C-PiB results. We derived the equation to express ¹⁸F-florbetaben (FBB) binding in CL units.

Methods

Paired PiB and FBB PET scans were obtained in 35 subjects. including ten young normal subjects aged under 45 years (33 ± 8 years). FBB images were acquired from 90 to 110 min after injection. Spatially normalized images were analysed using the standard CL method (SPM8 coregistration of PET data to MRI data and the MNI-152 atlas) and standard CL regions (cortex and whole cerebellum downloaded from http://www.gaain.org).

Results

FBB binding was strongly correlated with PiB binding (R ² = 0.96, SUVR_FBB = 0.61 × SUVR_PiB + 0.39). The equation to derive CL values from FBB SUVR was CL units = 153.4 × SUVR_FBB − 154.9. The CL value in the young normal subjects was −1.08 ± 6.81 for FBB scans compared to −0.32 ± 3.48 for PiB scans, giving a variance ratio of 1.96 (SD_{FBB CL}/SD_{PiB CL}).

Conclusions

¹⁸F-FBB binding is strongly correlated with PiB binding and FBB results can now be expressed in CL units.

http://ift.tt/2zhrAio

Grading and outcome prediction of pediatric diffuse astrocytic tumors with diffusion and arterial spin labeling perfusion MRI in comparison with 18F–DOPA PET

Abstract

Purpose

The aim of this study was to investigate MRI-derived diffusion weighted imaging (DWI) and arterial spin labeling (ASL) perfusion imaging in comparison with ¹⁸F–dihydroxyphenylalanine (DOPA) PET with respect to diagnostic performance in tumor grading and outcome prediction in pediatric patients with diffuse astrocytic tumors (DAT).

Methods

We retrospectively analyzed 26 children with histologically proven treatment naïve low and high grade DAT who underwent ASL and DWI performed within 2 weeks of ¹⁸F–DOPA PET. Relative ASL-derived cerebral blood flow max (rCBF max) and DWI-derived minimum apparent diffusion coefficient (rADC min) were compared with ¹⁸F–DOPA uptake tumor/normal tissue (T/N) and tumor/striatum (T/S) ratios, and correlated with World Health Organization (WHO) tumor grade and progression-free survival (PFS). Statistics included Pearson's chi-square and Mann-Whitney U tests, Spearman's rank correlation, receiver operating characteristic (ROC) analysis, discriminant function analysis (DFA), Kaplan-Meier survival curve, and Cox analysis.

Results

A significant correlation was demonstrated between rCBF max, rADC min, and ¹⁸F–DOPA PET data (p < 0.001). Significant differences in terms of rCBF max, rADC min, and ¹⁸F–DOPA uptake were found between low- and high-grade DAT (p ≤ 0.001). ROC analysis and DFA demonstrated that T/S and T/N values were the best parameters for predicting tumor progression (AUC 0.93, p < 0.001). On univariate analysis, all diagnostic tools correlated with PFS (p ≤ 0.001); however, on multivariate analysis, only ¹⁸F–DOPA uptake remained significantly associated with outcome (p ≤ 0.03), while a trend emerged for rCBF max (p = 0.09) and rADC min (p = 0.08). The combination of MRI and PET data increased the predictive power for prognosticating tumor progression (AUC 0.97, p < 0.001).

Conclusions

DWI, ASL and ¹⁸F–DOPA PET provide useful complementary information for pediatric DAT grading. ¹⁸F–DOPA uptake better correlates with PFS prediction. Combining MRI and PET data provides the highest predictive power for prognosticating tumor progression suggesting a synergistic role of these diagnostic tools.

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Erratum to: Guideline for PET/CT imaging of neuroendocrine neoplasms with 68 Ga-DOTA-conjugated somatostatin receptor targeting peptides and 18 F–DOPA

http://ift.tt/2zjEYlU

A new integrated dual time-point amyloid PET/MRI data analysis method

Abstract

Purpose

In the initial evaluation of patients with suspected dementia and Alzheimer's disease, there is no consensus on how to perform semiquantification of amyloid in such a way that it: (1) facilitates visual qualitative interpretation, (2) takes the kinetic behaviour of the tracer into consideration particularly with regard to at least partially correcting for blood flow dependence, (3) analyses the amyloid load based on accurate parcellation of cortical and subcortical areas, (4) includes partial volume effect correction (PVEC), (5) includes MRI-derived topographical indexes, (6) enables application to PET/MRI images and PET/CT images with separately acquired MR images, and (7) allows automation.

Methods

A method with all of these characteristics was retrospectively tested in 86 subjects who underwent amyloid (¹⁸F-florbetaben) PET/MRI in a clinical setting (using images acquired 90–110 min after injection, 53 were classified visually as amyloid-negative and 33 as amyloid-positive). Early images after tracer administration were acquired between 0 and 10 min after injection, and later images were acquired between 90 and 110 min after injection. PVEC of the PET data was carried out using the geometric transfer matrix method. Parametric images and some regional output parameters, including two innovative "dual time-point" indexes, were obtained.

Results

Subjects classified visually as amyloid-positive showed a sparse tracer uptake in the primary sensory, motor and visual areas in accordance with the isocortical stage of the topographic distribution of the amyloid plaque (Braak stages V/VI). In patients classified visually as amyloid-negative, the method revealed detectable levels of tracer uptake in the basal portions of the frontal and temporal lobes, areas that are known to be sites of early deposition of amyloid plaques that probably represented early accumulation (Braak stage A) that is typical of normal ageing. There was a strong correlation between age and the indexes of the new dual time-point amyloid imaging method in amyloid-negative patients.

Conclusions

The method can be considered a valuable tool in both routine clinical practice and in the research setting as it will standardize data regarding amyloid deposition. It could potentially also be used to identify early amyloid plaque deposition in younger subjects in whom treatment could theoretically be more effective.

http://ift.tt/2zxHeH6

The role of F-18 FDG PET/CT in evaluating the impact of HIV infection on tumor burden and therapy outcome in patients with Hodgkin lymphoma

Abstract

Background

To evaluate the impact of HIV infection on tumor burden and therapy outcome following treatment with chemotherapy in patients with Hodgkin lymphoma.

Methods

A total of 136 patients with classical Hodgkin lymphoma were studied (mean age ± SD = 32.31 ± 1.39 years, male = 86, female = 50). Advanced disease (stage III and IV) was present in 64% of patients. HIV infection was present in 57 patients while 79 patients were HIV-negative. Baseline F-18 FDG PET/CT was obtained in all patients. SUVmax, MTV and TLG were determined on the baseline scan to evaluate for tumor burden. All patients completed a standard regimen of adriamycin, bleomycin, vinblastine and dacarbazine (ABVD). After a median period of 8 weeks (range = 6 to 17 weeks), a repeat F-18 FDG PET/CT scan was obtained to evaluate response to therapy using Deauville 5-point scoring system.

Results

The HIV-positive and HIV-negative groups were similar with regards to age and disease stage. The groups were heterogeneous with respect to gender (p = 0.029). The SUVmax, MTV and TLG of lesions were not significant different between the two groups. Complete response was seen in 72.8% of the study population. Presence of HIV infection was associated with higher rate of treatment failure with 40.4% of the HIV-positive patients having treatment failure while only 17.7% of the HIV-negative patients had treatment failure (p = 0.0034). HIV infection was a significant predictor of response to chemotherapy. Effects of SUVmax, MTV, TLG and Ann Arbor stage of the disease were not statistically significant as predictors of therapy outcome. In a multiple logistic regression, presence of HIV infection still remained an independent predictor of therapy outcome in the presence of other factors such as SUVmax, MTV, TLG and the Ann Arbor stage of the disease.

Conclusions

HIV infection is not associated with a higher tumor burden in patients with Hodgkin lymphoma. HIV infection is, however, a strong predictor of poor therapy outcome in patients treated with standard regimen of ABVD.

http://ift.tt/2zjEPim

Diagnostic utility of PET/CT with 18 F-DOPA and 18 F-FDG in persistent or recurrent medullary thyroid carcinoma: the importance of calcitonin and carcinoembryonic antigen cutoff

Abstract

Purpose

This study sought to evaluate and compare the utility of 18-F-fluorodihydroxyphenylalanine (¹⁸F-DOPA) and 18-F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) for identification of lesions in patients with recurrent medullary thyroid carcinoma (MTC). In addition, we analyzed the correlation between the calcitonin (Ct), carcinoembryonic antigen (CEA) levels, each doubling time (DT), and PET positivity. We evaluated the reliability of the 150 pg/mL Ct cutoff set by the American Thyroid Association guidelines for further imaging (including ¹⁸F-DOPA PET/CT).

Methods

We prospectively recruited 18 patients with recurrent MTC, identified by elevation of Ct or CEA. Each patient underwent a ¹⁸F-FDG PET/CT and a ¹⁸F-DOPA PET/CT.

Results

Abnormal uptakes were detected with ¹⁸F-DOPA (n=12) and ¹⁸F-FDG (n=9), (sensitivity of 66.7% vs. 50%; p<0.01). Twenty-eight lesions were detected with ¹⁸F-DOPA vs. 16 lesions with ¹⁸F-FDG (1.56±1.5 vs. 0.89±1.18 lesions per patient; p=0.01). None of our patients showed additional lesions with ¹⁸F-FDG in comparison to ¹⁸F-DOPA. Patient-based detection rate increased significantly with Ct levels ≥150 pg/mL vs. Ct<150 pg/mL for both ¹⁸F-DOPA (sensitivity 90.9% vs. 28.6%; p=0.013) and ¹⁸F-FDG PET/CT (sensitivity 72.7% vs. 14.3%; p=0.025). Using a CEA cutoff of ≥5 ng/mL, detection rates of ¹⁸F-DOPA and ¹⁸F-FDG PET/CT were 81.1% and 72.7%, respectively. No correlation between Ct-DT or CEA-DT and PET positivity was found. Histological confirmation was obtained in eight patients.

Conclusions

¹⁸F-DOPA PET/CT appears to be superior to ¹⁸F-FDG PET/CT in detecting and locating lesions in patients with recurrent MTC. This technique tends to be especially useful in patients with negative results in other imaging modalities and Ct≥150 pg/mL or CEA≥5 ng/mL.

http://ift.tt/2zxs9Wl

βAPP Processing Drives Gradual Tau Pathology in an Age-Dependent Amyloid Rat Model of Alzheimer’s Disease

Abstract

The treatment of Alzheimer's disease (AD) remains challenging and requires a better in depth understanding of AD progression. Particularly, the link between amyloid protein precursor (APP) processing and Tau pathology development remains poorly understood. Growing evidences suggest that APP processing and amyloid-β (Aβ) release are upstream of Tau pathology but the lack of animal models mimicking the slow progression of human AD raised questions around this mechanism. Here, we described that an AD-like βAPP processing in adults wild-type rats, yielding to human APP, βCTF and Aβ levels similar to those observed in AD patients, is sufficient to trigger gradual Tauopathy. The Tau hyperphosphorylation begins several months before the formation of both amyloid plaques and tangle-like aggregates in aged rats and without associated inflammation. Based on a longitudinal characterization over 30 months, we showed that extrasynaptic and emotional impairments appear before long-term potentiation deficits and memory decline and so before Aβ and Tau aggregations. These compelling data allowed us to (1) experimentally confirm the causal relationship between βAPP processing and Tau pathology in vivo and without Tau transgene overexpression, (2) support the amyloidogenic cascade and (3) propose a 4-step hypothesis of prodromal AD progression.

http://ift.tt/2x4DcEN

Scholar : These new articles for The Law Teacher are available online

The online platform for Taylor & Francis Online content New for The Law Teacher and online now on Taylor & Francis Online: Original Articles "You must be joking": the role of humour in the law classroom Kate Offer , Natalie Skead & Angelyn Seen Pages: 1-19 | DOI: 10.1080/03069400.2017.1379182 To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Cosmetics, Vol. 4, Pages 42: Instrumental Evaluation of the Depigmenting Efficacy of an Oral Supplementation Containing Peptides and Chrysanthemum Extract for the Treatment of Melasma

Cosmetics, Vol. 4, Pages 42: Instrumental Evaluation of the Depigmenting Efficacy of an Oral Supplementation Containing Peptides and Chrysanthemum Extract for the Treatment of Melasma

Cosmetics doi: 10.3390/cosmetics4040042

Authors: Min Gui Juntao Kan Di Qu Yinbei Chen Rong Luo Yumin Liu Jun Du

The aim of this study was to assess the efficacy of an oral supplement (CP) containing collagen peptide, soy peptide, and chrysanthemum extract in Chinese female adult volunteers with melasma. The approval of the Institutional Ethics Committee of the third affiliated hospital, Sun-Yat Sen University, was obtained before the study. A signed consent was obtained from each volunteer prior to study to enable the volunteer to appreciate the aim of the study and the consequences of her consent. Sixty-two female volunteers aged 30–60 years were included in the study, and were randomized into a treatment group or a placebo group. The skin tone of the pigmented spots was evaluated using Chromameter, and pigment density was evaluated using Mexameter before and after the treatment. Significant changes in skin tone parameters of L value and ITA° (individual typology angle) were detected in the lesion area after the treatment (P &lt; 0.01). When compared with placebo group, the treatment group achieved significant improvement in the brightness of the pigmented spots at the 45 and 60-day time points. A significant decrease in the level of melanin was observed in the treatment group when compared with the placebo group (p &lt; 0.01). All data demonstrated through non-invasive in vivo instrumental measurement that daily oral intake of CP had clinical efficacy of reducing melasma severity.

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The distribution of the alpha7 nicotinic acetylcholine receptor in healthy aging: An in vivo positron emission tomography study with [18F]ASEM

Publication date: 15 January 2018
Source:NeuroImage, Volume 165
Author(s): Jennifer M. Coughlin, Yong Du, Hailey B. Rosenthal, Stephanie Slania, Soo Min Koo, Andrew Park, Ghedem Solomon, Melin Vranesic, Inga Antonsdottir, Caroline L. Speck, Kelly Rootes-Murdy, Alexandria Lerner, Steven P. Rowe, Yuchuan Wang, Wojciech G. Lesniak, Il Minn, Arnold Bakker, Gwenn S. Smith, Robert F. Dannals, Hiroto Kuwabara, Andrew Horti, Dean F. Wong, Martin G. Pomper
Altered function of the alpha7 nicotinic acetylcholine receptor (α7-nAChR) is implicated in several neuropsychiatric diseases. Nevertheless, studies of the human cerebral α7-nAChR even in healthy aging are limited in number and to postmortem tissue.MethodsThe distribution of the cerebral α7-nAChR was estimated in nine brain regions in 25 healthy volunteers (ages 21–86 years; median 57 years, interquartile range 52 years) using [¹⁸F]ASEM with positron emission tomography (PET) imaging. Regional total distribution volume (VT) measurements were calculated using the Logan method from each subject's 90 min dynamic PET data and their metabolite-corrected plasma input function. Spearman's rank or Pearson's correlation analysis was used depending on the normality of the data. Correlation between age and regional 1) volume relative to intracranial volume (volume ratio) and 2) [¹⁸F]ASEM VT was tested. Correlation between regional volume ratio and [¹⁸F]ASEM VT was also evaluated. Finally, the relationship between [¹⁸F]ASEM VT and neuropsychological measures was investigated in a subpopulation of 15 elderly healthy participants (those 50 years of age and older). Bonferroni correction for multiple comparisons was applied to statistical analyses.ResultsA negative correlation between tissue volume ratio and age was observed in six of the nine brain regions including striatum and five cortical (temporal, occipital, cingulate, frontal, or parietal) regions. A positive correlation between [¹⁸F]ASEM VT and age was observed in all nine brain regions of interest (ROIs). There was no correlation between [¹⁸F]ASEM VT and volume ratio in any ROI after controlling for age. Regional [¹⁸F]ASEM VT and neuropsychological performance on each of eight representative subtests were not correlated among the well-performing subpopulation of elderly healthy participants.ConclusionsOur results suggest an increase in cerebral α7-nAChR distribution over the course of healthy aging that should be tested in future longitudinal studies. The preservation of the α7-nAChR in the aging human brain supports the development of therapeutic agents that target this receptor for use in the elderly. Further study of the relationship between α7-nAChR availability and cognitive impairment over aging is needed.



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Habit strength is predicted by activity dynamics in goal-directed brain systems during training

Publication date: 15 January 2018
Source:NeuroImage, Volume 165
Author(s): Katharina Zwosta, Hannes Ruge, Thomas Goschke, Uta Wolfensteller
Previous neuroscientific research revealed insights into the brain networks supporting goal-directed and habitual behavior, respectively. However, it remains unclear how these contribute to inter-individual differences in habit strength which is relevant for understanding not only normal behavior but also more severe dysregulations between these types of action control, such as in addiction. In the present fMRI study, we trained subjects on approach and avoidance behavior for an extended period of time before testing the habit strength of the acquired stimulus-response associations. We found that stronger habits were associated with a stronger decrease in inferior parietal lobule activity for approach and avoidance behavior and weaker vmPFC activity at the end of training for avoidance behavior, areas associated with the anticipation of outcome identity and value. VmPFC in particular showed markedly different activity dynamics during the training of approach and avoidance behavior. Furthermore, while ongoing training was accompanied by increasing functional connectivity between posterior putamen and premotor cortex, consistent with previous assumptions about the neural basis of increasing habitualization, this was not predictive of later habit strength. Together, our findings suggest that inter-individual differences in habitual behavior are driven by differences in the persistent involvement of brain areas supporting goal-directed behavior during training.



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Definition and characterization of an extended multiple-demand network

Publication date: 15 January 2018
Source:NeuroImage, Volume 165
Author(s): J.A. Camilleri, V.I. Müller, P. Fox, A.R. Laird, F. Hoffstaedter, T. Kalenscher, S.B. Eickhoff
Neuroimaging evidence suggests that executive functions (EF) depend on brain regions that are not closely tied to specific cognitive demands but rather to a wide range of behaviors. A multiple-demand (MD) system has been proposed, consisting of regions showing conjoint activation across multiple demands. Additionally, a number of studies defining networks specific to certain cognitive tasks suggest that the MD system may be composed of a number of sub-networks each subserving specific roles within the system. We here provide a robust definition of an extended MDN (eMDN) based on task-dependent and task-independent functional connectivity analyses seeded from regions previously shown to be convergently recruited across neuroimaging studies probing working memory, attention and inhibition, i.e., the proposed key components of EF. Additionally, we investigated potential sub-networks within the eMDN based on their connectional and functional similarities. We propose an eMDN network consisting of a core whose integrity should be crucial to performance of most operations that are considered higher cognitive or EF. This then recruits additional areas depending on specific demands.



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