360 research outputs found
Modification of bacterial cell membrane to accelerate decolorization of textile wastewater effluent using microbial fuel cells: role of gamma radiation
The aim of the present work was to increase bacterial adhesion on anode via inducing membrane modifications to enhance textile wastewater treatment in Microbial Fuel Cell (MFC). Real textile wastewater was used in mediator-less MFCs for bacterial enrichment. The enriched bacteria were pre-treated by exposure to 1 KGy gamma radiation and were tested in MFC setup. Bacterial cell membrane permeability and cell membrane charges were measured using noninvasive dielectric spectroscopy measurements. The results show that pre-treatment using gamma radiation resulted in biofilm formation and increased cell permeability and exopolysaccharide production; this was reflected in both MFC performance (average voltage 554.67 mV) and decolorization (96.42%) as compared to 392.77 mV and 60.76% decolorization for non-treated cells. At the end of MFC operation, cytotoxicity test was performed for treated wastewater using a dermal cell line, the results obtained show a decrease in toxicity from 24.8 to 0 (v/v%) when cells were exposed to gamma radiation. Fourier-transform infrared (FTIR) spectroscopy showed an increase in exopolysaccharides in bacterial consortium exposed to increasing doses of gamma radiation suggesting that gamma radiation increased exopolysaccharide production, providing transient media for electron transfer and contributing to accelerating MFC performance. Modification of bacterial membrane prior to MFC operation can be considered highly effective as a pre-treatment tool that accelerates MFC performance
Modification of bacterial cell membrane to accelerate decolorization of textile wastewater effluent using microbial fuel cells: role of gamma radiation, salinity and endogenous biosurfactant induction
A combined approach was investigated to accelerate Microbial Fuel Cell (MFC) performance and textile wastewater decolorization through modifying bacterial membrane. The aim was to increase both bacterial adhesion on anode and electron mediator release. Ten Gram-positive exoelectrogenic bacteria were isolated from the anodic biofilm after decolorization of real textile waste water in mediator-less MFC. The isolates were identified and characterized, to understand the nature of the bacteria involved. According to the battery of tests performed, three factors gamma radiation, salinity and induction of endogenous biosurfactant were involved membrane modification. Dielectric measurement, a non-invasive technique, was used to measure the cell membrane permeability and cell surface charge. Plackett-Burman experimental design was carried out to determine the key contributor among the three studied factors. Exposing the cells to 1 KGy gamma radiation led to 7.84- and 1.71- fold increase in total surface-charge and cell-permeability, respectively. Scanning Electron Microscope (SEM) images and surface-bound protein concentrations for the samples indicated that biofilm formation increased under the same conditions. These results have been reflected on the power density profiles and decolorization of textile wastewater. Modification of bacterial membrane prior to MFC operation can be considered highly effective as a pre-treatment tool that accelerates MFC performance
CO2 dissolution and design aspects of a multiorifice oscillatory baffled column
Dissolution of CO2 in water was studied for a batch vertical multiorifice baffled column (MOBC) with varying orifice diameters (d0) of 6.4-30 mm and baffle open area (α) of 15-42%. Bubble size distributions (BSDs) and the overall volumetric CO2 mass transfer coefficient (KLa) were experimentally evaluated for very low superficial gas velocities, UG of 0.12-0.81 mm s-1, using 5% v/v CO2 in the inlet gas stream at a range of fluid oscillations (f = 0-10 Hz and x0 = 0-10 mm). Remarkably, baffles presenting large do = 30 mm and α = 36%, therefore in the range typically found for single-orifice oscillatory baffled columns, were outperformed with respect to BSD control and CO2 dissolution by the other baffle designs or the same aerated column operating without baffles or fluid oscillations. Flow visualization and bubble tracking experiments also presented in this study established that a small do of 10.5 mm combined with a small value of α = 15% generates sufficient, strong eddy mixing capable of generating and trapping an extremely large fraction of microbubbles in the MOBC. This resulted in increased interfacial area yielding KLa values up to 65 ± 12 h-1 in the range of the UG tested, representing up to 3-fold increase in the rate of CO2 dissolution when compared to the unbaffled, steady column. In addition, a modi fied oscillatory Reynolds number, ReâČo and Strouhal number, St' were presented to assist on the design and scale-up of gas-liquid systems based on multiorifice oscillatory ba ffled columns. This work is relevant to gas-liquid or multiphase chemical and biological systems relying on efficient dissolution of gaseous compounds into a liquid medium.BBSRC -European Commissio
Controlling liver cancer internationally: A qualitative study of clinicians' perceptions of current public policy needs
<p>Abstract</p> <p>Background</p> <p>Liver cancer is the fifth most common cancer in men and the seventh for women. Usually because of late diagnosis, the prognosis for liver cancer remains poor, resulting in liver cancer being the third most common cause of death from cancer. While some countries have treatment guidelines, little is known or understood about the strategies needed for liver cancer control internationally.</p> <p>Objective</p> <p>To explore leading liver cancer clinician's perceptions of the current public policy needs to control liver cancer internationally.</p> <p>Methods</p> <p>Key informant interviews were conducted with a range of liver cancer clinicians involved in policy in eleven countries. Interviews were digitally recorded, transcribed verbatim, translated (where necessary), de-identified and analyzed by two researchers using a constant comparative method.</p> <p>Results</p> <p>Twenty in-depth semi-structured interviews were conducted in: Australia, China, France, Germany, Italy, Japan, Spain, South Korea, Taiwan, Turkey and the United States. Nine themes were identified and cluster into three groups: 1) Promoting prevention via early risk assessment, focusing on viral hepatitis and other lifestyle factors; 2) Increasing political, public and medical community awareness; and 3) Improving funding for screening, liver cancer surveillance and treatment.</p> <p>Conclusion</p> <p>This study is an important step towards developing an evidence-based approach to assessing preparedness for implementing comprehensive liver cancer control strategies. Evaluation mechanisms to assess countries' performance on the needs described are needed. Future research will concentrate of understanding how these needs vary across countries and the optimal strategies to improve the diagnosis and prognosis of patients with liver cancer internationally.</p
Cigarettes' use and capabilities-opportunities-motivation-for-behavior model:a multi-country survey of adolescents and young adults
The use of cigarettes among adolescents and young adults (AYA) is an important issue. This study assessed the association between regular and electronic-cigarettes use among AYA and factors of the Capability-Motivation-Opportunity-for-Behavior-change (COM-B) model. A multi-country survey was conducted between August-2020 and January-2021, Data was collected using the Global-Youth-Tobacco-Survey and Generalized-Anxiety-Disorder-7-item-scale. Multi-level logistic-regression-models were used. Use of regular and electronic-cigarettes were dependent variables. The explanatory variables were capability-factors (COVID-19 status, general anxiety), motivation-factors (attitude score) and opportunity-factors (country-level affordability scores, tobacco promotion-bans, and smoke free-zones) controlling for age and sex. Responses of 6,989-participants from 25-countries were used. Those who reported that they were infected with COVID-19 had significantly higher odds of electronic-cigarettes use (AOR = 1.81, P = 0.02). Normal or mild levels of general anxiety and negative attitudes toward smoking were associated with significantly lower odds of using regular-cigarettes (AOR = 0.34, 0.52, and 0.75, P < 0.001) and electronic-cigarettes (AOR = 0.28, 0.45, and 0.78, P < 0.001). Higher affordability-score was associated with lower odds of using electronic-cigarettes (AOR = 0.90, P = 0.004). Country-level-smoking-control policies and regulations need to focus on reducing cigarette affordability. Capability, motivation and opportunity factors of the COM-B model were associated with using regular or electronic cigarettes
Anxiety among adolescents and young adults during COVID-19 pandemic: A multi-country survey
(1) Background: Adolescents-and-young-adults (AYA) are prone to anxiety. This study assessed AYA's level of anxiety during the COVID-19 pandemic; and determined if anxiety levels were associated with country-income and region, socio-demographic profile and medical history of individuals. (2) Methods: A survey collected data from participants in 25 countries. Dependent-variables included general-anxiety level, and independent-variables included medical problems, COVID-19 infection, age, sex, education, and country-income-level and region. A multilevel-multinomial-logistic regression analysis was conducted to determine the association between dependent, and independent-variables. (3) Results: Of the 6989 respondents, 2964 (42.4%) had normal-anxiety, and 2621 (37.5%), 900 (12.9%) and 504 (7.2%) had mild, moderate and severe-anxiety, respectively. Participants from the African region (AFR) had lower odds of mild, moderate and severe than normal-anxiety compared to those from the Eastern-Mediterranean-region (EMR). Also, participants from lower-middle-income-countries (LMICs) had higher odds of mild and moderate than normal-anxiety compared to those from low-income-countries (LICs). Females, older-adolescents, with medical-problems, suspected-but-not-tested-for-COVID-19, and those with friends/family-infected with COVID-19 had significantly greater odds of different anxiety-levels. (4) Conclusions: One-in-five AYA had moderate to severe-anxiety during the COVID-19-pandemic. There were differences in anxiety-levels among AYAs by region and income-level, emphasizing the need for targeted public health interventions based on nationally-identified priorities
A multi-country study on the impact of sex and age on oral features of COVID-19 infection in adolescents and young adults
Background: Oral diseases are features of COVID-19 infection. There is, however, little known about oral diseases associated with COVID-19 in adolescents and young adults (AYA). Therefore, the aim of this study was to assess oral lesionsâ association with COVID-19 infection in AYA; and to identify if sex and age will modify these associations. Methodology: Data was collected for this cross-sectional study between August 2020 and January 2021 from 11-to-23 years old participants in 43-countries using an electronic validated questionnaire developed in five languages. Data collected included information on the dependent variables (the presence of oral conditions- gingival inflammation, dry mouth, change in taste and oral ulcers), independent variable (COVID-19 infection) and confounders (age, sex, history of medical problems and parentsâ educational level). Multilevel binary logistic regression was used for analysis. Results: Complete data were available for 7164 AYA, with 7.5% reporting a history of COVID-19 infection. A significantly higher percentage of participants with a history of COVID-19 infection than those without COVID-19 infection reported having dry mouth (10.6% vs 7.3%, AOR = 1.31) and taste changes (11.1% vs 2.7%, AOR = 4.11). There was a significant effect modification in the association between COVID-19 infection and the presence of dry mouth and change in taste by age and sex (P = 0.02 and < 0.001). Conclusion: COVID-19 infection was associated with dry mouth and change in taste among AYA and the strength of this association differed by age and sex. These oral conditions may help serve as an index for suspicion of COVID-19 infection in AYA
Systematic Reviews and Meta-Analyses of the Procedure-specific Risks of Thrombosis and Bleeding in General Abdominal, Colorectal, Upper Gastrointestinal, and Hepatopancreatobiliary Surgery
\ua9 2024 Lippincott Williams and Wilkins. All rights reserved.Objective: To provide procedure-specific estimates of symptomatic venous thromboembolism (VTE) and major bleeding after abdominal surgery. Background: The use of pharmacological thromboprophylaxis represents a trade-off that depends on VTE and bleeding risks that vary between procedures; their magnitude remains uncertain. Methods: We identified observational studies reporting procedure-specific risks of symptomatic VTE or major bleeding after abdominal surgery, adjusted the reported estimates for thromboprophylaxis and length of follow-up, and estimated cumulative incidence at 4 weeks postsurgery, stratified by VTE risk groups, and rated evidence certainty. Results: After eligibility screening, 285 studies (8,048,635 patients) reporting on 40 general abdominal, 36 colorectal, 15 upper gastrointestinal, and 24 hepatopancreatobiliary surgery procedures proved eligible. Evidence certainty proved generally moderate or low for VTE and low or very low for bleeding requiring reintervention. The risk of VTE varied substantially among procedures: in general abdominal surgery from a median of <0.1% in laparoscopic cholecystectomy to a median of 3.7% in open small bowel resection, in colorectal from 0.3% in minimally invasive sigmoid colectomy to 10.0% in emergency open total proctocolectomy, and in upper gastrointestinal/hepatopancreatobiliary from 0.2% in laparoscopic sleeve gastrectomy to 6.8% in open distal pancreatectomy for cancer. Conclusions: VTE thromboprophylaxis provides net benefit through VTE reduction with a small increase in bleeding in some procedures (eg, open colectomy and open pancreaticoduodenectomy), whereas the opposite is true in others (eg, laparoscopic cholecystectomy and elective groin hernia repairs). In many procedures, thromboembolism and bleeding risks are similar, and decisions depend on individual risk prediction and values and preferences regarding VTE and bleeding
Prognostic significance of cortactin levels in head and neck squamous cell carcinoma: comparison with epidermal growth factor receptor status
Cortactin is an actin-binding Src substrate involved in cell motility and invasion. In this study, we sought to examine the prognostic importance of cortactin protein expression in head and neck squamous cell carcinoma (HNSCC). To do so, cortactin and EGF receptor (EGFR) expression was retrospectively evaluated by immunohistochemistry in a tissue microarray composed of 176 HNSCCs with a mean follow-up time of 5 years. Cortactin immunoreactivity was weak to absent in normal epithelial tissue. Overexpression of the protein in 77 out of 176 tumours (44%) was associated with more advanced tumour-node-metastasis stage and higher histologic grade. Cortactin overexpression was associated with significantly increased local recurrence rates (49 vs 28% for high and low expressing carcinomas, respectively), decreased disease-free survival (17 vs 61%), and decreased the 5-year overall survival of (21 vs 58%), independently of the EGFR status. In multivariate analysis, cortactin expression status remained an independent prognostic factor for local recurrence, disease-free survival, and overall survival. Importantly, we identified a subset of patients with cortactin-overexpressing tumours that displayed low EGFR levels and a survival rate that equalled that of patients with tumoral overexpression of both EGFR and cortactin. These findings identify cortactin as a relevant prognostic marker and may have implications for targeted therapies in patients with HNSCC
Allelopathic effect of black mustard tissues and root exudates on some crops and weeds
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