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Σάββατο 24 Δεκεμβρίου 2016

Prognostic impact of preoperative anemia on non-muscle-invasive bladder carcinoma treated with GreenLight laser vaporization

Abstract

In this study, we aimed to evaluate the impact of preoperative anemia (PA) on oncological outcomes among patients with non-muscle-invasive bladder cancer (NMIBC) treated with GreenLight laser vaporization of bladder tumor (PV-BT). Between January 2010 and December 2015, 407 patients with NMIBC who underwent PV-BT surgery were stratified into normal and anemia groups based on the World Health Organization classification (anemia cutoff value: hemoglobin level, <13.0 m g/dL in men and <12.0 mg/dL in women). The Student's t test and chi-square test were performed to assess the effects of PA on clinical and pathological characteristics of patients with NMIBC. The Kaplan-Meier method was used to investigate the influence of PA on oncological survival outcomes. Before PV-BT, 139 patients (34.2%) were anemic. No significant differences in age, sex, smoking habit, tumor size, focality, grade, and stage were found between the anemia and normal groups. At a median follow-up period of 32.5 months (range, 8–60 months), 74 patients (18.2%) had urothelial recurrence, 30 (7.4%) died from any cause, and 21 (5.2%) died from bladder cancer. In the Kaplan-Meier analysis, preoperative anemia was significantly associated with decreased cancer-specific survival (CSS) and overall survival (OS) of the patients with NMIBC. However, recurrence-free survival (RFS) showed no statistically significant difference between the PA and normal groups. The preoperative anemic patients with NMIBC who underwent PV-BT surgery had worse CSS and OS. PA can be a useful and cost-effective prognostic marker in the clinical practice for NMIBC treatment.



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Data for β-lactoglobulin conformational analysis after (-)-epigallocatechin gallate and metal ions binding

Publication date: February 2017
Source:Data in Brief, Volume 10
Author(s): Liangliang Zhang, Indra Dev Sahu, Man Xu, Yongmei Wang, Xinyu Hu
This data article contains complementary results related to the paper "Effect of metal ions on the binding reaction of (-)-epigallocatechin gallate to β-lactoglobulin" (Zhang et al., 2017) [1]. Data was obtained by circular dichroism (CD) spectroscopy to investigate potential β-lactoglobulin (β-Lg) conformational changes with different concentrations of EGCg and Cu2+ or Al3+ added to β-Lg. 500µL of the 25µM β-Lg solution containing EGCg (25µM) or metal ions (0–500µM) were measured, and the spectra were recorded. CD spectroscopy data present in this article indicated that the β-Lg-Cu, β-Lg-Al and β-Lg-EGCg interaction resulted in unfolding of the secondary structure of β-Lg.



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The influence of implantoplasty on the diameter, chemical surface composition, and biocompatibility of titanium implants

Abstract

Objectives

The objective of the study was to assess the influence of implantoplasty (IP) on the diameter, chemical surface composition, and biocompatibility of titanium implants in vitro.

Material and methods

Twenty soft tissue-level (TL; machined transmucosal—M and rough endosseous part—SLA) and 20 bone-level (BL; SLA) implants were allocated to IP covering 3 or 6 mm of the structured surface (SLA) area. The samples were subjected to diameter, energy-dispersive X-ray spectroscopy (EDX), and cell viability (ginigval fibroblasts, 6 days) assessments.

Results

Median diameter reductions varied between 0.1 (TL 3 mm) and 0.2 mm (TL 6 mm). EDX analysis revealed that IP and M surfaces were characterized by a comparable quantity (Wt%) of elements C, O, Na, Cl, K, and Si, but a significantly different quantity of elements Ti and Al. When compared to SLA surfaces, significant differences were noted for elements C, O, Na, Ti, and Al. At BL implants, the extension of IP (i.e., 3 to 6 mm) was associated with a significant increase in cell viability.

Conclusions

IP applied to SLA implants was associated with (i) a minimal diameter reduction, (ii) an undisturbed cell viability, and (iii) a chemical elemental composition comparable to M surfaces.

Clinical relevance

This specific IP procedure appears to be suitable for the management of exposed SLA implant surfaces.



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Outcomes of implant therapy in patients with a history of aggressive periodontitis. A systematic review and meta-analysis

Abstract

Objective

To investigate the outcomes of implant therapy in partially dentate patients treated for aggressive periodontitis (GAgP) in comparison to periodontally healthy (HP) and patients treated for chronic periodontitis (CP) utilizing radiographic and clinical parameters.

Material and methods

An electronic search of databases, supplemented by hand searching, was conducted to identify relevant clinical studies. Sequential screenings at the title, abstract and full-text levels were performed independently and in duplicate. A random effects meta-analysis was conducted and bias corrected bootstrap 95 % confidence intervals were estimated for group comparisons.

Results

The search strategy revealed a total of 899 results. After title screening, abstract scanning, and full-text reading, seven articles fulfilled the inclusion criteria. The 3-year survival rate for CP and HP patients was 100 % while in GAgP subjects, the respective value was 97.98 %; this difference being statistically significant. The 3-year mean marginal bone loss (MBL) was 1.07 mm for the GAgP group, 0.47 mm for the CP group, and 0.69 mm for the HP group. A significant difference between the GAgP and CP groups was identified (p < 0.05). The weighted mean differences of MBL concerning the above groups were also calculated and examined for statistical significance in both 1 and 3 years.

Conclusions

The 3-year survival rate and peri-implant marginal bone loss was found statistically significantly lower in GAgP subjects (SR 97.98 % vs 100 %) in comparison to HP and CP individuals.

Clinical relevance

The outcome of implant therapy in terms of survival rate and marginal bone loss is considered very important for the clinician in decision making when placing implants in patients with a history of aggressive periodontitis.



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Opiorphin in burning mouth syndrome patients: a case-control study

Abstract

Objectives

Opiorphin is a pentapeptide isolated from human saliva that suppresses pain from chemically induced inflammation and acute physical pain. Burning mouth syndrome (BMS) is a chronic condition of a burning sensation in the mouth, where no underlying dental or medical cause can be identified. We aimed to measure the level of opiorphin in whole unstimulated (UWS) and stimulated (SWS) saliva of patients with BMS.

Materials and methods

Originally developed and validated LC-MS/MS method was used for opiorphin quantification. Samples were obtained from 29 BMS patients and 29 age- and sex-matched controls.

Results

The average concentration of opiorphin in UWS and SWS in the BMS group was 8.13 ± 6.45 and 5.82 ± 3.59 ng/ml, respectively. Opiorphin in BMS patients' UWS was significantly higher, compared to the control group (t = 2.5898; p = 0.0122). SWS opiorphin levels were higher, but not significantly, in BMS patients than in controls.

Conclusions

Our results indicate that higher quantities of salivary opiorphin in BMS may be a consequence of chronic pain, but we cannot exclude that they occur as a result of emotional and behavioral imbalances possibly associated with BMS. To our knowledge, this is the first original article measuring opiorphin in a pain disorder.

Clinical relevance

Opiorphin may be a measurable biomarker for chronic pain, which could help in objectifying otherwise exclusively a subjective experience. Increased opiorphin could serve as a universal objective indicator of painful conditions. Since opiorphin may also reflect emotional and socio-relational imbalances occurring with BMS, it could as well represent a biomarker for BMS. Knowledge on opiorphin's involvement in pain pathways could contribute to developing new clinical diagnostic methods for BMS.



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Exploration of bacterial species associated with the salivary microbiome of individuals with a low susceptibility to dental caries

Abstract

Objective

Dental caries is caused by acidogenic plaque microbiota formed on saliva-bathed tooth surfaces, in which multiple organisms act collectively to initiate and expand a cavity. We explored bacterial species associated with the salivary microbiome of individuals with low susceptibility to dental caries.

Materials and methods

The bacterial composition of saliva from 19 young adults was analyzed using barcoded pyrosequencing of the 16S rRNA gene; we compared 10 caries-experienced (CE) and nine caries-free (CF) individuals. A quantitative PCR assay of saliva from 139 orally healthy adults aged 40–59 years was carried out to confirm the result obtained by pyrosequencing analysis.

Results

The microbiomes of CF individuals showed more diverse communities with a significantly greater proportion of the genus Porphyromonas. Among operational taxonomic units (OTUs) corresponding to the genus Porphyromonas, the OTU corresponding to P. pasteri was the most predominant and its relative abundance in CF individuals was significantly greater than in CE individuals (P < 0.001, Wilcoxon rank sum test). A quantitative PCR assay of saliva confirmed that the amounts of P. pasteri were significantly higher in individuals with lower caries experience (filled teeth <15, n = 67) than in those with higher caries experience (filled teeth ≥15, n = 72) (P < 0.001, Student's t test).

Conclusion

These results revealed an association between a greater abundance of P. pasteri and lower susceptibility to dental caries.

Clinical relevance

P. pasteri may be a bacterial species that could potentially be used as a marker for maintaining a healthy oral microbiome against dental caries.



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VideoEndocrinology™ High-Impact Videos

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FREE ACCESS through January 6, 2017.

Transoral Excision of Nodal Metastatic Papillary Thyroid Carcinoma
William M. Dougherty, Mark J. Jameson, David C. Shonka Jr

Transoral Endoscopic Thyroidectomy Vestibular Approach
Angkoon Anuwong, Thanyawat Sasanakietkul, Pornpeera Jitpratoom

Transoral Robotic Thyroidectomy
Jeremy D. Richmon, Ralph P. Tufano, Jon Russell, Andrew Day, Hamad M. Chaudhary, Salem I. Noureldine

The post VideoEndocrinology™ High-Impact Videos appeared first on American Thyroid Association.



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Decomposition of 3,5-dinitrobenzamide in aqueous solution during UV/H 2 O 2 and UV/TiO 2 oxidation processes

Abstract

3,5-Dinitrobenzamide has been widely used as a feed additive to control coccidiosis in poultry, and part of the added 3,5-dinitrobenzamide is excreted into wastewater and surface water. The removal of 3,5-dinitrobenzamide from wastewater and surface water has not been reported in previous studies. Highly reactive hydroxyl radicals from UV/hydrogen peroxide (H2O2) and UV/titanium dioxide (TiO2) advanced oxidation processes (AOPs) can decompose organic contaminants efficiently. In this study, the decomposition of 3,5-dinitrobenzamide in aqueous solution during UV/H2O2 and UV/TiO2 oxidation processes was investigated. The decomposition of 3,5-dinitrobenzamide fits well with a fluence-based pseudo-first-order kinetics model. The decomposition in both two oxidation processes was affected by solution pH, and was inhibited under alkaline conditions. Inorganic anions such as NO3−, Cl−, SO42−, HCO3−, and CO32− inhibited the degradation of 3,5-dinitrobenzamide during the UV/H2O2 and UV/TiO2 oxidation processes. After complete decomposition in both oxidation processes, approximately 50% of 3,5-dinitrobenzamide was decomposed into organic intermediates, and the rest was mineralized to CO2, H2O, and other inorganic anions. Ions such as NH4+, NO3−, and NO2− were released into aqueous solution during the degradation. The primary decomposition products of 3,5-dinitrobenzamide were identified using time-of-flight mass spectrometry (LCMS-IT-TOF). Based on these products and ions release, a possible decomposition pathway of 3,5-dinitrobenzamide in both UV/H2O2 and UV/TiO2 processes was proposed.



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Determination of optimum polymeric coagulant in palm oil mill effluent coagulation using multiple-objective optimisation on the basis of ratio analysis (MOORA)

Abstract

The main limitation of a conventional palm oil mill effluent (POME) ponding system lies in its inability to completely decolourise effluent. Decolourisation of effluent is aesthetically and environmentally crucial. However, determination of the optimum process parameters is becoming more complex with the increase of the number of coagulants and responses. The primary objective of this study is to determine the optimum polymeric coagulant in the coagulation–flocculation process of palm oil mill effluent by considering all output responses, namely lignin–tannin, low molecular mass coloured compounds (LMMCC), chemical oxygen demand (COD), ammonia nitrogen (NH3-N), pH and conductivity. Here, multiple-objective optimisation on the basis of ratio analysis (MOORA) is employed to discretely measure multiple response characteristics of five different types of coagulants as a function of assessment value. The optimum coagulant is determined based on the highest assessment value and was identified as QF25610 (cationic polyacrylamide). On the other hand, the lowest assessment value was represented by AN1800 (anionic polyacrylamide). This study highlights the simplicity of MOORA approach in handling various input and output parameters, and it may be useful in other wastewater treatment processes as well.



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Bacterial communities associated with anaerobic debromination of decabromodiphenyl ether from mangrove sediment

Abstract

This study evaluated decabromodiphenyl ether (BDE-209) anaerobic debromination and bacterial community changes in mangrove sediment. BDE-209 debromination rates were enhanced with zerovalent iron compared to without zerovalent iron in the sediment. BDE-209 debromination rates in microcosms constructed with sediments collected in autumn were higher than in microcosms constructed with sediments collected in spring and were higher at the Bali sampling site than the Guandu sampling site. The intermediate products resulting from the reductive debromination of BDE-209 in sediment were nona-BDE (BDE-206, BDE-207), octa-BDEs (BDE-196, BDE-197), hepta-BDEs (BDE-183, BDE-184, BDE-191), hexa-BDEs (BDE-137, BDE-138, BDE-154, BDE-157), penta-BDEs (BDE-85, BDE-99, BDE-100, BDE-126), tetra-BDEs (BDE-47, BDE-49, BDE-66, BDE-77), tri-BDEs (BDE-17, BDE-28), and di-BDEs (BDE-15). Fifty bacterial genera associated with BDE-209 debromination were identified. Overall, 12 of the 50 bacterial genera were reported to be involved in dehalogenation of aromatic compounds. These bacteria have high potential to be BDE-209 debromination bacteria. Different combinations of bacterial community composition exhibit different abilities for BDE-209 anaerobic debromination.



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Simultaneous sulfide removal, nitrification, and electricity generation in a microbial fuel cell equipped with an oxic cathode

Abstract

With sulfide as an anodic electron donor and ammonium as a cathodic substrate, the feasibility of simultaneous sulfide removal, nitrification, and electricity generation was investigated in a microbial fuel cell (MFC) equipped with an oxic cathode. Successful simultaneous sulfide removal, nitrification, and electricity generation in this MFC were achieved in 35 days, with the sulfide and ammonium removal percent of 92.7 ± 1.4 and 96.4 ± 0.3%, respectively. The maximum power density increased, but the internal resistance decreased with the increase of feeding sulfide concentration from 62.9 ± 0.3 to 238.5 ± 0.2 mg S/L. Stable ammonium removal with complete nitrification, preparing for future denitrification, was obtained throughout the current study. Sulfide removal loading significantly increased with the increase of feeding sulfide concentration at each external resistance, but no significant correlation between sulfide removal loading and external resistance was found at each feeding sulfide concentration. The charge recovery and anodic coulombic efficiency (CE) significantly decreased with the increase of external resistance. High feeding sulfide concentration led to low anodic CE. Granular sulfur deposition was found on the anode graphite fiber. The appropriate feeding sulfide concentration for sulfide removal and sulfur deposition was deemed to be 178.0 ± 1.7 mg S/L, achieving a sulfur deposition percent of 69.7 ± 0.6%.



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Molecular and structural changes induced by essential oil treatments in Vicia faba roots detected by FTIR and FTNIR spectroscopy

Abstract

Essential oils have recognized antimicrobial and antifungal properties which allow their utilization in agriculture like an alternative to pesticides, but their utilization requires the knowledge of all the potential structural changes and damages produced by the interaction with the vegetal organisms. In this paper, we investigated the effects of two essential oils, the tea tree oil (TTO) and the mixture of clove and rosemary oils (C + R), on the molecular structure of Vicia faba roots by Fourier transform infrared (FTIR) and Fourier near infrared transform (FTNIR) spectroscopy. FTIR spectroscopy showed structural modifications of the absorption bands related to DNA (1100 and 1050 cm−1, carbohydrate backbones, and nucleotide bands within 900 and 850 cm−1), proteins (1700 and 1600 cm−1 amide I band, 1580 and 1520 cm−1 amide II band), and lipids (methylene group of aliphatic chains between 2950 and 2800 cm−1). The changes in the secondary structures of proteins consisted of a denaturation depending on increased presence of random coil structures. In addition, in the samples treated with TTO oils, we observed the presence of protein oxidation, an effect negligible instead for the C + R-treated samples. The modified shapes of the infrared methyl bands of aliphatic chains suggested an increased lipid disorder which could also determine lipid peroxidation. The changes observed for the DNA structures at the highest concentration of the above essential oils can be related to the genotoxic effect of eugenol, an important constituent of both TTO and C + R mixture oils. FTNIR spectroscopy showed the modified shape of the second overtone bands belonging to methyl and methylene groups, between 8500 and 8000 cm−1. This confirmed the increased lipid disorders already observed by FTIR spectroscopy. The results obtained on the probe organism V. faba show that FTIR and FTNIR spectroscopy can become a useful support to the conventional cytogenetic tests used in the evaluation of the allelopathic uses of essential oils in agriculture.



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Arsenic trioxide induces ROS activity and DNA damage, leading to G0/G1 extension in skin fibroblasts through the ATM-ATR-associated Chk pathway

Abstract

Arsenic (As) toxicity is a global health problem, affecting millions of people. Exposure to arsenic, mostly via drinking water, has been associated with cancer of skin, lungs, and blood, in addition to several kinds of skin lesions. The present study focused on the effect of arsenic trioxide (As2O3) on normal skin fibroblast cells. Specifically, the effect of As2O3 on ROS generation and oxidative stress was investigated. Proteins involved in the DNA damage signaling pathway and cell cycle were also studied. As2O3 induced the generation of intracellular ROS. Immunohistochemistry analysis revealed a dose-dependent increase in the number of 8-OHdG-positive cells, an indication of oxidative stress. Cell cycle analysis by flow cytometry demonstrated that As2O3 caused a significant percentage of cells to accumulate in the G0/G1 phase with a concomitant reduction in the S phase. Increases in the activated forms of DNA damage signaling proteins, ATM and ATR, and their effector molecules, Chk2 and p53, were also observed. In addition, expression of oncogene p21 was also increased. The study shows that exposure of normal skin fibroblast cells to As2O3 could lead to cell cycle arrest through ATM/ATR and DNA damage signaling pathways. In conclusion, we report here that arsenic trioxide increases cellular oxidative stress leading to shift in cell cycle and leads to DNA damage through ATM/ATR and the CHK-dependent signaling pathway.



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A socio-scientific analysis of the environmental and health benefits as well as potential risks of cassava production and consumption

Abstract

Due to its high adaptability, cassava (Manihot esculenta Crantz) is one of the world's most cultivated and consumed plants after maize and rice. However, there are relatively few scientific studies on this important crop. The objective of this review was therefore to summarize and discuss the available information on cassava cropping in order to promote sustainable practices in terms of production and consumption. Cassava cultivation has been expanding recently at the global scale and is widely consumed in most regions of South America, Africa, and Asia. However, it is also characterized by the presence in its roots of potentially toxic hydrocyanic acid. Furthermore, cassava can also absorb pollutants as it is currently cultivated near roads or factories and generally without consideration for potential sources of soil, water, or atmospheric pollution. Careful washing, peeling, and adequate preparation before eating are therefore crucial steps for reducing human exposure to both environmental pollutants and natural hydrocyanic acid. At present, there is not enough precise data available on this staple food crop. To improve our knowledge on the nutritive benefits versus health risks associated with cassava consumption, further research is necessary to compare cassava cultivars and precisely study the influence of preparation methods.



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Dynamic monitoring and prediction of Dianchi Lake cyanobacteria outbreaks in the context of rapid urbanization

Abstract

Water crises have been among the most serious environmental problems worldwide since the twenty-first century. A water crisis is marked by a severe shortage of water resources and deteriorating water quality. As an important component of water resources, lake water quality has deteriorated rapidly in the context of fast urbanization and climate change. This deterioration has altered the water ecosystem structure and influenced lake functionality. To curb these trends, various strategies and procedures have been used in many urban lakes. Among these procedures, accurate and responsive water environment monitoring is the basis of the forecasting and prevention of large-scale cyanobacteria outbreaks and improvement of water quality. To dynamically monitor and predict the outbreak of cyanobacteria in Dianchi Lake, in this study, wireless sensors networks (WSNs) and the geographic information system (GIS) are used to monitor water quality at the macro-scale and meso-scale. Historical, real-time water quality and weather condition data were collected, and a combination prediction model (adaptive grey model (AGM) and back propagation artificial neural network (BPANN)) was proposed. The correlation coefficient (R) of the simulation experiment reached 0.995. Moreover, we conducted an empirical experiment in Dianchi Lake, Yunnan, China using the proposed method. R was 0.93, and the predicting error was 4.77. The results of the experiment suggest that our model has good performance for water quality prediction and can forecast cyanobacteria outbreaks. This system provides responsive forewarning and data support for lake protection and pollution control.



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Evaluation of combined noxious effects of siduron and cadmium on the earthworm Eisenia fetida

Abstract

Environmental contaminants do not often occur as individual chemicals but rather in complex mixtures whose joint effects can create a strong toxicity to surrounding organisms. To determine the combined harmful effects of siduron (herbicide) and cadmium (heavy metal) toward Eisenia fetida earthworms, samples of worm's coelomocytes were subjected to siduron and cadmium (Cd) at sublethal concentrations (lower than LC50)-siduron 0, 0.8, 2.4, and 7.2 μg cm−2 Cd 0, 0.4, 0.8, and 1.6 μg cm−2 in filter paper contact assay, both as individual compounds and combinations. The CI-isobologram model was utilized to reveal the types of toxicological interactions between siduron and cadmium in inducing DNA damage toward earthworms. The results indicated that tail DNA percentage (TDNA %) at individual siduron and cadmium concentrations (with the exception of the lowest concentration of Cd 0.04 μgcm−2) were highly significant compared to those of the control (p < 0.01). Tail moments (TM) at individual Cd concentrations (0.8 and 1.6 μg cm−2) were highly significant compared to those of the control (p < 0.05), while the increase of TM for individual siduron was only significant (p < 0.05) at 7.2 μg cm−2 which is the highest dose/concentration of siduron used in this study. The combinations of siduron and Cd indicated a significant synergism (CI < 1) at the lower effect levels and a significant antagonism (CI > 1) at the higher effect levels. The synergistic effect for a particular combination of chemicals suggests that there might be a possible risk connected to the coincidence of these chemicals.



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Performance and emission analysis on blends of diesel, restaurant yellow grease and n -pentanol in direct-injection diesel engine

Abstract

Yellow grease from restaurants is typically waste cooking oil (WCO) free from suspended food particles with free fatty acid (FFA) content less than 15%. This study proposes an approach to formulate a renewable, eco-friendly fuel by recycling WCO with diesel (D) and n-pentanol (P) to improve fuel-spray characteristics. Three ternary blends (D50-WCO45-P5, D50-WCO40-P10 and D50-WCO30-P20) were selected based on the stability tests and prepared with an objective to substitute diesel by 50% with up to 45% recycled component (WCO) and up to 20% bio-component (n-pentanol) by volume. The fuel properties of these ternary blends were measured and compared. The emission impacts of these blends on a diesel engine were analysed in comparison with diesel and D50-WCO50 (50% of diesel + 50% of WCO) under naturally articulated and EGR (exhaust gas recirculation) approaches. Doping of n-pentanol showed improved fuel properties when compared to D50-WCO50. Viscosity is reduced up to 45%. Cetane number and density were comparable to that of diesel. Addition of n-pentanol to D50-WCO50 presented improved brake specific fuel consumption (BSFC) for all ternary blends. Brake thermal efficiency (BTE) of D50-WCO30-P20 blend is comparable to diesel due to improved atomization. Smoke opacity reduced, HC emissions increased and CO emissions remained unchanged with doping n-pentanol in the WCO. NOx emission increases with increase in n-pentanol and remained lower than diesel and all load conditions. However, NOx can be decreased by up to threefold using EGR. By adopting this approach, WCO can be effectively reused as a clean energy source by negating environmental hazards before and after its use in diesel engines, instead of being dumped into sewers and landfills.



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In situ remediation of contaminated marinesediment: an overview

Abstract

Sediment tends to accumulate inorganic and persistent hydrophobic organic contaminants representing one of the main sinks and sources of pollution. Generally, contaminated sediment poses medium- and long-term risks to humans and ecosystem health; dredging activities or natural resuspension phenomena (i.e., strongly adverse weather conditions) can remobilize pollution releasing it into the water column. Thus, ex situ traditional remediation activities (i.e., dredging) can be hazardous compared to in situ techniques that try to keep to a minimum sediment mobilization, unless dredging is compulsory to reach a desired bathymetric level. We reviewed in situ physico-chemical (i.e., active mixing and thin capping, solidification/stabilization, chemical oxidation, dechlorination, electrokinetic separation, and sediment flushing) and bio-assisted treatments, including hybrid solutions (i.e., nanocomposite reactive capping, bioreactive capping, microbial electrochemical technologies). We found that significant gaps still remain into the knowledge about the application of in situ contaminated sediment remediation techniques from the technical and the practical viewpoint. Only activated carbon-based technologies are well developed and currently applied with several available case studies. The environmental implication of in situ remediation technologies was only shortly investigated on a long-term basis after its application, so it is not clear how they can really perform.



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Molecular-based detection of potentially pathogenic bacteria in membrane bioreactor (MBR) systems treating municipal wastewater: a case study

Abstract

Although membrane bioreactor (MBR) systems provide better removal of pathogens compared to conventional activated sludge processes, they do not achieve total log removal. The present study examines two MBR systems treating municipal wastewater, one a full-scale MBR plant and the other a lab-scale anaerobic MBR. Both of these systems were operated using microfiltration (MF) polymeric membranes. High-throughput sequencing and digital PCR quantification were utilized to monitor the log removal values (LRVs) of associated pathogenic species and their abundance in the MBR effluents. Results showed that specific removal rates vary widely regardless of the system employed. Each of the two MBR effluents' microbial communities contained genera associated with opportunistic pathogens (e.g., Pseudomonas, Acinetobacter) with a wide range of log reduction values (< 2 to >5.5). Digital PCR further confirmed that these bacterial groups included pathogenic species, in several instances at LRVs different than those for their respective genera. These results were used to evaluate the potential risks associated both with the reuse of the MBR effluents for irrigation purposes and with land application of the activated sludge from the full-scale MBR system.



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Ruptured Abdominal Aortic Aneurysm Post-EVAS: Nellix Explantation

Publication date: Available online 24 December 2016
Source:European Journal of Vascular and Endovascular Surgery
Author(s): M. Cherchi, S. Camparini




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