Converting environmental risks to benefits by using spent coffee grounds (SCG) as a valuable resource

Abstract

Coffee is perhaps one of the most vital ingredients in humans' daily life in modern world. However, this causes the production of million tons of relevant wastes, i.e., plastic cups, aluminum capsules, coffee chaff (silver skin), and spent coffee grounds (SCG), all thrown untreated into landfills. It is estimated that 1 kg of instant coffee generates around 2 kg of wet SCG; a relatively unique organic waste stream, with little to no contamination, separated directly in the source by the coffee shops. The produced waste has been under researchers' microscope as a useful feedstock for a number of promising applications. SCG is considered a valuable, nutrients rich source of bioactive compounds (e.g., phenolics, flavonoids, carotenoids, lipids, chlorogenic and protocatechuic acid, melanoidins, diterpenes, xanthines, vitamin precursors, etc.) and a useful resource material in other processes (e.g., soil improver and compost, heavy metals absorbent, biochar, biodiesel, pellets, cosmetics, food, and deodorization products). This paper aims to provide a holistic approach for the SCG waste management, highlighting a series of processes and applications in environmental solutions, food industry, and agricultural sector. Thus, the latest developments and approaches of SCG waste management are reviewed and discussed.

https://ift.tt/2Jl2BTU

Nanostructured catalysts applied to degrade atrazine in aqueous phase by heterogeneous photo-Fenton process

Abstract

SBA-15 and KIT-6 materials have been synthesized and modified with iron salts by the wet impregnation method with different metal loadings. The different mesostructures obtained were characterized by N₂ adsorption–desorption at 77 K, X-ray diffraction, temperature-programmed reduction, and ultraviolet–visible spectroscopy. These iron-containing mesostructured materials have been successfully tested for the heterogeneous photo-Fenton degradation of aqueous solutions of dangerous herbicides, such as atrazine, using UV–visible light irradiation, at room temperature and close to neutral pH. The results showed that the Fe/SBA-15 (10%) and Fe/KIT-6 (5%) catalysts exhibited the highest activities. However, the Fe/KIT-6 (5%) catalyst with minor Fe loading than Fe/SBA-15 (10%) presented a higher degradation of atrazine (above 98% in a reaction time of 240 min). Therefore, the interconnectivity of the cage-like mesopores had an important influence on the catalytic activity, favoring probably mass-transfer effects. Thus, the high performance of these materials indicates that the heterogeneous via of photo-Fenton process can also be efficiently employed to treat wastewaters containing pollutants such as herbicides, in order to reduce them to simplest and less toxic molecules.

https://ift.tt/2LctGWw

Bismuth vanadate-based semiconductor photocatalysts: a short critical review on the efficiency and the mechanism of photodegradation of organic pollutants

Abstract

The number of publications on photocatalytic bismuth vanadate-based materials is constantly increasing. Indeed, bismuth vanadate is gaining stronger interest in the photochemical community since it is a solar-driven photocatalyst. However, the efficiency of BiVO₄-based photocatalyst under sunlight is questionable: in most of the studies investigating the photodegradation of organic pollutants, only few works identify the by-products and evaluate the real efficiency of BiVO₄-based materials. This short review aims to (i) present briefly the principles of photocatalysis and define the photocatalytic efficiency and (ii) discuss the formation of reactive species involved in the photocatalytic degradation process of pollutants and thus the corresponding photodegradation mechanism could be determined. All these points are developed in a comprehensive discussion by focusing especially on pure, doped, and composite BiVO₄. Therefore, this review exhibits a critical overview on different BiVO₄-based photocatalytic systems with their real efficiency. This is a necessary knowledge for potential implementation of BiVO₄ materials in environmental applications at larger scale than laboratory conditions.

https://ift.tt/2Jq5brL

Neuroendocrine and immune disequilibrium as a probable link between metabolic syndrome and carcinogenesis

Publication date: Available online 2 June 2018
Source:Medical Hypotheses
Author(s): Mariyana G. Hristova
Numerous investigations prove a higher incidence of carcinogenesis in metabolic syndrome (MetS). They indicate the important role of obesity, elevated inflammatory biomarkers, hyperinsulinemia, hyperglycemia, and dyslipidemia as well. Elevated plasma insulin and free insulin-like growth factor-1 (IGF-1) levels stimulate cell proliferation. The present publication considers the role of neuroendocrine and immune disequilibrium in MetS as a reason for transition to carcinogenesis. It emphasizes the role of hormonal disbalance, i.e. hyperleptinemia, hyperinsulinemia, hypercortisolemia, hypercatecholaminemia, hyperestrogenemia and hyperandrogenemia in MetS. It is presumed that these important components modify cellular microenvironment towards carcinogenesis. The interactions between neurotrophins, leptin, and mast cells and the alterations in the hypothalamo-hypophyseal-adrenal axis in MetS are discussed. It is assumed that they are the consequence of inflammatory distress followed by hormonal and immune disbalance at a central level as well as of enlarged adipose tissue and changed adipocyte microenvironment leading, finally, to carcinogenesis.



https://ift.tt/2JqPaBZ

Practical guidelines for clinical magnetoencephalography – Another step towards best practice

Publication date: Available online 2 June 2018
Source:Clinical Neurophysiology
Author(s): Arjan Hillebrand, William Gaetz, Paul L. Furlong, Alida A. Gouw, Cornelis J. Stam




https://ift.tt/2LQukKC

Comprehensive evaluation of EMG and biopsy findings supported by computer simulations – preliminary study

Publication date: Available online 2 June 2018
Source:Clinical Neurophysiology
Author(s): Ewa Zalewska, Anna Kaminska, Biruta Kierdaszuk, Elżbieta Szmidt-Salkowska, Małgorzata Gawel
ObjectiveThe aim was to compare muscle fiber diameters obtained from standard muscle biopsy and from computer simulations based on recorded motor unit potentials (MUPs).MethodsElectromyography (EMG) and muscle biopsy were performed in 14 patients with a suspicion of a neuromuscular disorder. Histograms of the simulated muscle fiber diameters (SMFDs) were compared with those from the biopsy. Results. The values of the SMFDs were similar to those in the muscle biopsy for the same patient (p=0.05) in all 14 cases.ConclusionsComprehensive evaluation of EMG and biopsy findings supported by computer simulations may help resolve the discrepancy between the assessment of muscle by EMG and biopsy by explaining different results obtained with these two methods.SignificanceEvaluation of the SMFDs that are comparable to biopsy findings extends the amount of information available from EMG.



https://ift.tt/2JaCkEv

Global Burden of Cancer, 1990 to 2016

This systematic analysis evaluates the cancer burden over time at the global and national levels measured in incidence, mortality, years lived with disability, years of life lost, and disability-adjusted life-years.

https://ift.tt/2st1Qyp

Defining Survivorship Trajectories Across Patients With Solid Tumors

This cohort study uses Surveillance, Epidemiology, and End Results data to determine high- and low-risk periods for 68 cancer types that could define when survivorship care might best be overseen by oncologists and when to transition to primary care physicians.

https://ift.tt/2JbkiSH

New Business Models to Accelerate Innovation in Pediatric Oncology Therapeutics

This review discusses the problems associated with funding for development of drug therapy to treat cancer in children and proposes a financial model to address the challenges.

https://ift.tt/2J8MuJG

Boosting the catalytic activity of natural magnetite for wet peroxide oxidation

Abstract

This work explores the modification of naturally occurring magnetite by controlled oxidation (200–400 °C, air atmosphere) and reduction (300–600 °C, H₂ atmosphere) treatments with the aim of boosting its activity in CWPO. The resulting materials were fully characterized by XRD, XPS, TGA, TPR, SEM, and magnetization measurements, allowing to confirm the development of core-shell type structures. The magnetite core of the solid remained unchanged upon the treatment whereas the Fe(II)/Fe(III) ratio of the shell was modified (e.g. 0.42, 0.11 and 0.63 values were calculated for pristine Fe₃O₄, Fe₃O₄-O400, and Fe₃O₄-R400, respectively). The performance of the catalysts was tested in the CWPO of sulfamethoxazole (SMX) (5 mg L⁻¹) under ambient conditions and circumneutral pH (pH₀ = 5), using the stoichiometric dose of H₂O₂ (25 mg L⁻¹) and a catalyst load of 1 g L⁻¹. The key role of the ferrous species on the mineral shell was evidenced. Whereas the oxidation of magnetite led to significantly slower degradation rates of the pollutant, its reduction gave rise to a dramatic increase, achieving the complete removal of SMX in 1.5 h reaction time with the optimum catalyst (Fe₃O₄-R400) compared to the 3.5 h required with the pristine mineral. A reaction mechanism was proposed for SMX degradation, and a kinetic equation based on the Eley-Rideal model was accordingly developed. This model successfully fitted the experimental results. The stability of Fe₃O₄-R400 was evaluated upon five sequential runs. Finally, the versatility of the catalytic system was proved in real environmentally relevant water matrices.

https://ift.tt/2HdQFOO

CFD modeling of a UV-A LED baffled flat-plate photoreactor for environment applications: a mining wastewater case

Abstract

The use of ultraviolet light in photoreactors for wastewater treatment has become popular as an alternative of known chemical oxidative substances. UV LED light represents cheaper, robust, and versatile alternative to traditional UV lamps. In this study, it was designed and evaluated a photoreactor with an approach of chemical fluid dynamics (CFD) and experimental validation. The evaluation consisted of (1) CFD velocity profile analysis, (2) characterization of the average light distribution with potassium ferrioxalate actinometry, (3) degradation of a typical recalcitrant metallic cyanocomplex Fe(CN)₆³⁻, and (4) scavenger effect analysis in the photodegradation using potassium persulfate. Actinometrical essay concluded that the system was able to receive 1.93 μE/s. The reactor operated under turbulent regime and best result for Fe(CN)₆³⁻ degradation was obtained at 4 h of operation, using 5-W UV-A LEDs, with pH ~ 7 and 10 mM de S₂O₈²⁻. Baffled photoreactor demonstrated to be useful for this type of illumination and wastewater treatment.

https://ift.tt/2ssYnQp

Wintertime characteristic of peroxyacetyl nitrate in the Chengyu district of southwestern China

Abstract

Atmospheric concentrations of peroxyacetyl nitrate (PAN) were measured in Ziyang in December 2012 to provide basic knowledge of PAN in the Chengyu district and offer recommendations for air pollution management. The PAN pollution was relatively severe in Ziyang in winter, with the maximum and average PAN concentrations of 1.61 and 0.55 ppbv, respectively, and a typical single-peak diurnal trend in PAN and theoretical PAN lost by thermal decomposition (TPAN) were observed. PAN and O₃ concentrations were correlated (R² = 0.52) and the ratios of daily maximum PAN to O₃ ([PAN]/[O₃] ratio) ranged from 0.013 to 0.108, with an average of 0.038. Both acetone and methyl ethyl ketone (MEK) were essential for producing the acetylperoxy radicals (PA) and subsequently PAN in Ziyang in winter, and PAN concentrations at the sampling site exhibited more sensitivity to volatile organic compound (VOC) concentrations than nitrogen oxide (NO_x) levels. Therefore, management should focus on reducing VOCs emissions, in particular those that produce acetone and MEK through photolysis and oxidizing reactions. In addition, the influence of relative humidity (RH) on the heterogeneous reactions between PAN and PM_2.5 in the atmospheric environment may have led to the strong correlation between observed PM_2.5 and PAN in Ziyang in winter. Furthermore, a typical air pollution event was observed on 17–18 December 2012, which Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) and PSCF simulations suggest that it was caused by the local formation and the regional transport of polluted air masses from Hanzhong, Nanchong, and Chengdu.

https://ift.tt/2srJaPI

In vitro comparison of an Er:YAG laser-activated bleaching system with different light-activated bleaching systems for color change, surface roughness, and enamel bond strength

Abstract

To compare an Er:YAG laser-activated bleaching system with different light-activated in-office bleaching systems for color change, surface roughness, and post-bleaching enamel bond strength. 51 enamel slabs were prepared from the sound buccal enamel of extracted bovine teeth. The teeth were randomly divided into three groups according to different light-activated office bleaching systems (n = 17): diode laser (Epic, Biolase) (940 nm, 7 W, continuous mode), Er:YAG laser (LightWalker, Fotona) (2940 nm, 50 mJ, 10 Hz, 1000 μs), and LED (Radii Plus) (440–480 nm, 1500 mW/cm²). All systems were used with their compatible bleaching agents according to manufacturers' recommendations. The tooth color and surface roughness (Ra) were assessed at baseline and after bleaching using a spectrophotometer and a surface profilometer, respectively. The color change was determined by the CIE L*a*b* system (ΔE, ΔL*, Δa*, Δb*). Kruskal-Wallis test was used for color change whereas Kruskal-Wallis and Wilcoxon tests were used to analyze the roughness data. For shear bond strength test (SBS), composite cylinders were bonded on bleached enamel samples 14 days after bleaching procedures and stored in water (37 °C). Specimens were then debonded with a universal testing machine at 1 mm/min and data were analyzed by using Kruskal-Wallis test. All the tested bleaching systems were effective on color change (ΔE > 3.3) and produced similar color change (p > 0.05). There were no significant differences among the Ra values of the groups neither at baseline nor after bleaching (p > 0.05). However, comparing the baseline and after bleaching Ra values, a significant increase was observed for all tested groups (p < 0.05). Significant differences were also found among all systems for SBS (p < 0.05). The highest values were obtained in Er:YAG group, whereas the LED group revealed the lowest values (p < 0.05). All tested bleaching systems were effective on tooth whitening, whereas they all led to an increase on surface roughness. Although the current Er:YAG laser-activated bleaching system did not differ from other tested bleaching systems according to color change and surface roughness, it appears to provide better results in terms of SBS.

https://ift.tt/2J8rvCP

A systematic review and meta-analysis of the prevalence and phenotype of adult-onset atopic dermatitis

Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Harrison H. Lee, Kevin R. Patel, Vivek Singam, Supriya Rastogi, Jonathan I. Silverberg
BackgroundPrevious studies found conflicting results about whether atopic dermatitis (AD) begins in adulthood.ObjectiveTo determine rates, predictors and phenotypical differences of adult-onset AD.MethodsA systematic review was performed of all published observational studies in MEDLINE, EMBASE, GREAT, LILACS, Cochrane Library, and Scopus that analyzed the age of AD onset beyond 10 years of age. Two reviewers performed study title/abstract review and data abstraction. Pooled meta-analysis of the proportion of adult-onset AD was performed using random-effects weighting (I²=99.3%).ResultsOverall, 25 studies met inclusion criteria. Seventeen studies reported age of AD-onset past 16 years and had sufficient data for meta-analysis. The pooled proportion (95% CI) of adult-onset AD was 26.1% (16.5-37.2%). Similar results were found in sensitivity analyses by diagnostic method for AD, study region, and gender. Phenotypical differences were observed across studies for adult vs. child onset AD, including higher rates of foot dermatitis and personal history of atopy, but lower rates of flexural lesions and other signs and symptoms.LimitationsCharacteristics of adult- vs. child-onset AD were not commonly reported.ConclusionsAD is not only a disease of childhood. One in 4 adults with AD report adult-onset disease. Adult-onset AD was associated with distinct clinical characteristics.



https://ift.tt/2kJk7n3

Folliculitis Decalvans: Effectiveness of Therapies and Prognostic Factors In A Multicenter Series of 60 Patients With Long-Term Follow-Up

Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): L. Miguel-Gómez, A.R. Rodrigues-Barata, A. Molina-Ruiz, A. Martorell-Calatayud, P. Fernández-Crehuet, R. Grimalt, D. Barco, S. Arias-Santiago, C. Serrano-Falcón, F.M. Camacho, D. Saceda-Corralo, P. Jaén-Olasolo, S. Vañó-Galván




https://ift.tt/2sARZFX

REPLY to MS#JAAD-D-18-00380

Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Samir Arbache




https://ift.tt/2ssEYz7

Reply to: comment on “Liquid nitrogen cryotherapy for chronic recalcitrant interdigital candidiasis of toe-spaces – an uncontrolled pilot study”

Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Vijay Zawar, Manoj Pawar, R Raghunatha Reddy, Antonio Chuh




https://ift.tt/2sBLXVC

About melanocyte activation in idiopathic guttate hypomelanosis by 5-fluorouracil tattooing

Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Carlos Gustavo Wambier




https://ift.tt/2kI0DPr

Influence of age and marital status on stage at diagnosis and survival of patients with Merkel cell carcinoma: a SEER based cohort study

Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Michael A. Liu, Jannett Nguyen, Jane A. Driver




https://ift.tt/2HfmLcK

Engineering cationic defects in transparent tin oxide superlattices

Publication date: 5 October 2018
Source:Materials & Design, Volume 155
Author(s): Zhemi Xu, Adnan Younis, Claudio Cazorla, Jiabao Yi, Dewei Chu, Sean Li
The lack of understanding in engineering cation defects in metal oxides has impeded the development of high performance, and transparent electronic devices. Through studying the formation energy of various cationic defects in Mn-doped SnO2 via simulation, we found Mn³⁺ cations occupy the interstitial sites of SnO2 nanocrystals, and we proved that such defects can be engineered to significantly improve resistive switching performance of tin oxide-based devices. With this finding, a new solution-processed approach has been developed to synthesize Mn-doped SnO2 nanocrystals with a self-assembly technique for high quality transparent Mn-doped SnO2 thin film fabrication. Defect migration behavior of the Mn-doped SnO2 thin film was studied by building a metal-oxide-metal sandwich device. The effects of cationic defects, such as Mn interstitials, on the charge transport behavior were further studied to reveal the underlying mechanism. This study provides new insights into the design and engineering of defects in transparent oxides for high-density data storage applications.

Graphical abstract

https://ift.tt/2HdilmQ