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Water-to-air transfer of branched and linear PFOA:Influence of ph,concentration and water type

Emerging Contaminants 2017年第1期3卷 46-53页

作者： jana h.johansson hong Yan Urs Berger Ian T.Cousins Department of Environmental Science and Analytical Chemistry(ACES) Stockholm UniversitySvante Arrhenius v€ag 811418 StockholmSweden State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghaiChina Department Analytical Chemistry Helmholtz Centre for Environmental Research e UFZLeipzigGermany

The volatilisation of perfluorooctanoic acid(PFOA)was measured experimentally at a range of ph values using a previously published laboratory ***-to-air transfer was studied for five structural isomers,namely:the linear isomer(n-PFOA)and the four most commonly occurring branched isomers(3-,4-,5-and 6-PFOA).The influence of water concentration and water type on the ph-dependent waterto-air transfer was also investigated for *** water-to-air transfer was studied over the course of 48 h at ph values ranging from 0.2 to *** all experimental conditions tested,the volatilisation of PFOA was negligible at ph>*** experiments performed with MilliQ water,volatilisation increased with decreasing water *** experiments performed with tap water and lake water,maximum volatilisation was observed at ph *** concentration of PFOA in water had no influence on the ph value at which water-to-air transfer was observed(*** phhe concentration range tested(0.1e50 mg/L PFOA in deionised water).Although the percentage of PFOA volatilised was significantly different for the four branched isomers at low ph,volatilisation was not observed above ph 2.5 for any branched isomer suggesting that all PFOA isomers have a low ***,these laboratory results demonstrate that volatilisation of any structural isomer of PFOA from water is negligible at environmentally-relevant *** is unlikely that PFOA isomers will be fractionated in the environment as a result of volatilisation because it is a process of negligible environmental relevance.

关键词： PFOA Isomer Branched Acid dissociation pKa

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Slowly filling the gaps in our approach to diet and nutrition in inflammatory bowel diseases

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hepatobiliary Surgery and Nutrition 2024年第2期13卷 333-335页

作者： Fadi h.Mourad Najwa F.Mourad jana G.hashash Department of Internal Medicine Faculty of MedicineAmerican University of BeirutBeirutLebanon Department of Nutrition and Food Sciences Faculty of Agricultural and Food SciencesAmerican University of BeirutBeirutLebanon Division of Gastroenterology and hepatology Mayo ClinicJacksonvilleFLUSA

Malnutrition is an underrecognized complication among patients with inflammatory bowel diseases(IBD)and despite that,it has been reported to affect 16%of patients with IBD(1).Malnutrition is at least 5 times more prevalent among hospitalized patients with IBD compared to patients without IBD(2).Poor outcomes including increased rates of hospitalization,increased surgeries as well as lower response to medical treatment have been associated with malnutrition(2).Patients with Crohn’s disease(CD)and ulcerative colitis(UC)suffer from malnutrition due to reduced oral intake,malabsorption,increased energy and protein requirements and an increase in nutritional losses associated with inflammatory *** societies recommend screening for malnutrition at IBD diagnosis and routinely during follow ***,guidance about diet in IBD is often controversial and represents a challenge for care providers as well as *** role of diet has been investigated as a risk factor for IBD etiopathogenesis,as a potential therapy for active disease and as a supportive measure in the ill malnourished patient.

关键词： Exclusive enteral nutrition(EEN) Crohn’s disease exclusion diet(CDED) nutrition diet

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Investigating the coagulation of non-proteinaceous algal organic matter: Optimizing coagulation performance and identification of removal mechanisms

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Journal of Environmental Sciences 2019年第5期31卷 25-34页

作者： jana Naceradska Katerina Novotna Lenka Cermakova Tomas Cajthaml Martin Pivokonsky Institute of hydrodynamics of the Czech Academy of Sciences Institute of Microbiology of the Czech Academy of Sciences

The removal of algal organic matter(AOM) is a growing concern for the water treatment industry worldwide. The current study investigates coagulation of non-proteinaceous AOM(AOM after protein separation), which has been minimally explored compared with proteinaceous fractions. Jar tests with either aluminum sulphate(alum) or polyaluminium chloride(PACl) were performed at doses of 0.2–3.0 mg Al per 1 mg of dissolved organic carbon in the p h range 3.0–10.5. Additionally, non-proteinaceous matter was characterized in terms of charge, molecular weight and carbohydrate content to assess the treatability of its different fractions. Results showed that only up to 25% of non-proteinaceous AOM can be removed by coagulation under optimized conditions. The optimal coagulation p h(6.6–8.0 for alum and 7.5–9.0 for PACl) and low surface charge of the removed fraction indicated that the prevailing coagulation mechanism was adsorption of non-proteinaceous matter onto aluminum hydroxide precipitates. The lowest residual Al concentrations were achieved in very narrow p h ranges, especially in the case of PACl. high-molecular weight saccharidelike organics were amenable to coagulation compared to low-molecular weight(heir high content in non-proteinaceous matter(about 67%) was the reason for its low removal. Comparison with our previous studies implies that proteinaceous and nonproteinaceous matter is coagulated under different conditions due to the employment of diverse coagulation mechanisms. The study suggests that further research should focus on the removal of low-molecular weight AOM, reluctant to coagulate, with other treatment processes to minimize its detrimental effect on water safety.

关键词： Algal organic matter Chlorella vulgaris Coagulation Flocculation Non-proteinaceous matter Water treatment

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Electron transfer dynamics in Schottky junction photocatalyst during electron donor-assisted hydrogen production

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Journal of Materials Science & Technology 2023年第28期159卷 1-9页

作者： Jianjun Zhang Jingjing Liu Zheng Meng Sanjib jana Linxi Wang Bicheng Zhu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of Geosciences68 Jincheng StreetWuhan 430078China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological University21 Nanyang LinkSingapore 637371Singapore Jiangxi Key Laboratory of Surface Engineering Jiangxi Science and Technology Normal UniversityNanchang 330038China

Electron donors(EDs)are widely used to improve the h 2 production performance of Schottky junction photocatalysts,but the functions of EDs are still unknown from the perspective of electron transfer ***,Pt nanocluster-decorated CdS nanorod is successfully prepared to construct a typical CdS/Pt Schottky *** nanoclusters with a diameter of∼2 nm are deposited on the surface of CdS nanorods by in situ photoreduction at sub-zero *** CdS/Pt photocatalyst using lactic acid shows a higher h_(2)production rate of 4762μmol g^(-1)h^(-1)compared to that using methanol,tri-ethanolamine,and *** understand the cause,the dynamics of photogenerated carriers in CdS/Pt photocatalysts during ED-assisted h_(2)production are revealed by femtosecond transient absorption *** the four organic EDs,lactic acid enables the fastest electron transfer rate of 1.8×10^(9)s^(-1)and the highest electron transfer efficiency of 76%at the CdS/Pt interface due to the most efficient hole *** work sheds light on the importance of efficient interfacial electron transfer for im-proving the photocatalytic performance of Schottky junction photocatalysts.

关键词： Transient absorption spectroscopy Interfacial electron transfer Electron transfer rate Electron transfer efficiency hole consumption

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Observation of Resistive Switching Memory by Reducing Device Size in a New Cr/CrO_x/TiO_x/TiN Structure

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Nano-Micro Letters 2015年第4期7卷 392-399页

作者： Debanjan jana Subhranu Samanta Sourav Roy Yu Feng Lin Siddheswar Maikap Thin Film Nano Tech. Lab. Department of Electronic Engineering Chang Gung University

The resistive switching memory characteristics of 100 randomly measured devices were observed by reducing device size in a Cr/Cr Ox/Ti Ox/Ti N structure for the first *** electron microscope image confirmed a viahole size of 0.4 lm.A 3-nm-thick amorphous Ti Oxwith 4-nm-thick polycrystalline Cr Oxlayer was observed.A small 0.4-lm device shows reversible resistive switching at a current compliance of 300 l A as compared to other larger size devices(1–8 lm)owing to reduction of leakage current through the Ti *** device-to-device uniformity with a yield of[85%has been clarified by weibull distribution owing to higher slope/shape *** switching mechanism is based on oxygen vacancy migration from the Cr Oxlayer and filament formation/rupture in the Ti *** read pulse endurance of[105cycles,good data retention of 6 h,and a program/erase speed of 1 ls pulse width have been obtained.

关键词： CrOx TiOx Resistive switching memory Slope/shape factor Device size

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To eat or get heat： Behavioral trade-offs between thermoregulation and feeding in gregarious necrophagous larvae

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Insect Science 2018年第5期25卷 883-893页

作者： jana Podhorna Cindy Aubernon Marie Borkovcova Julien Boulay Valery hedouin Damien Charabidze Department of Zoology Fisheries Hydrobiology and Apiculture Mendel University in Brno Czech Repubfic Unite de Taphonomie Medico-Legale University of Lille CHU Lille EA France

The thermoregulation behavior ofLucilia sericata larvae （Diptera： Calliphori- dae）, a necrophagous species that feeds on vertebrate cadavers, was investigated. These larvae require high heat incomes to develop, and can elevate temperatures by forming large aggregates. We hypothesized that L. sericata larvae should continue to feed at temperatures up to 38 ℃, which can be reached inside larval masses. Thermal regulation behavior such as movement between a hot food spot and colder areas was also postulated. The hypotheses were tested by tracking for 1 h the activity of single, starved third instar larvae in a Petri dish containing 1 food spot （FS） that was heated to a constant temperature of 25 ℃, 34 ℃ or 38 ℃ with an ambient temperature of 25 ℃. The influence of previous conspecific activity in the food on larval behavior was also tested. The crops of larvae were dissected to monitor food content in the digestive systems. Based on relative crop measurements, larvae fed at all food temperatures, but temperature strongly affected larval behavior and kinematics. The total time spent by larvae in FS and the duration of each stay decreased at high FS temperature. Previous activity of conspecifics in the food slightly increased the time spent by larvae in FS and also decreased the average distance to FS. Therefore, necrophagous L. sericata larvae likely thermoregulate during normal feeding activities by adjusting to local fluctuations in temperature, particularly inside maggot masses. By maintaining a steady internal body temperature, larvae likely reduce their development time.

关键词： blowflies Calliphoridae forensic entomology foraging thermoregulation video tracking

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Solid and liquid state characterization of tetrahydrocurcumin using XRPD, FT-IR, DSC, TGA, LC-MS, GC-MS, and NMR and its biological activities

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Journal of Pharmaceutical Analysis 2020年第4期10卷 334-345页

作者： Mahendra Kumar Trivedi Parthasarathi Panda Kalyan Kumar Sethi Mayank Gangwar Sambhu Charan Mondal Snehasis jana Trivedi Global Inc. Henderson89052NevadaUSA Trivedi Science Research Laboratory Pvt.Ltd. Thane(W)-400604MaharashtraIndia

Tetrahydrocurcumin(ThC)is one of the major metabolites of curcumin(CUR),an ancient bioactive natural polyphenolic *** research article describes both the solid and liquid state characterization of ThC using advanced spectroscopic and thermo-analytical ***-inflammatory,anti-oxidant,and neuroprotective activities of ThC were investigated using in vitro cell *** chromatography-mass spectrometry analysis revealed that our sample comprised 95.15%ThC,0.51%tetrahydrodemethoxycurcumin(ThDC),3.40%hexahydrocurcumin,and 0.94%*** chromatography-mass spectrometry analysis indicated the presence of 96.68%ThC and 3.32%*** in solution existed as keto-enol tautomers in three different forms at different retention time,but the enol form was found to be dominant,which was also supported by nuclear magnetic resonance *** was thermally stable up to 335.55*** exhibited more suppression of cytokines(TNF-a,IL-1b,and MIP-1a)than CUR in a concentration-dependent manner in mouse splenocytes,while NK-cell and phagocytosis activity was increased in *** showed a significant reduction of free radicals(LPO)along with improved antioxidant enzymes(SOD and catalase)and increased free radical scavenging activity against ABTSt radicals in hepG2 *** displayed higher protection capability than CUR from oxidative stress and neuronal damage by improving cell viability against h2O2 induced hepG2 cells and MPPt induced Sh-SY5Y cells,respectively,in a concentration-dependent ***,a variation of the biological activities of ThC might rely on its keto-enol form and the presence of other ThC analogs as *** present study could be advantageous for further research on ThC for better understanding its physicochemical properties and biological variation.

关键词： Tetrahydrocurcumin Liquid chromatography-mass spectrometry Spectroscopic and thermal analysis Keto-enol tautomer Anti-inflammatory Antioxidant

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Impact of a clinical pathway on treatment outcome in patients with acute pancreatitis

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World Journal of Gastroenterology 2015年第30期21卷 9150-9155页

作者： Miroslav Vujasinovic jana Makuc Bojan Tepes Apolon Marolt Zdenko Kikec Nace Robac Department of Internal Medicine General Hospital Slovenj Gradec Abakus Medico Diagnostic Centre Rogaska

AIM:To determine the impact of a clinical pathway(CP) on acute pancreatitis(AP) treatment ***:A retrospective analysis of medical records was performed. We compared the results of AP treatment outcome over two time periods in our centre,before(2006-2007) and after(2010-2012) the implementation of a CP. The CP comprised the following indicators of quality:performance of all laboratory tests on admission(including lipids and carbohydrate deficient transferrin),determination of AP aetiology,abdomen ultrasound(US) within the first 24 h after admission,contrast-enhanced computed tomography of the abdomen in all cases of suspected pancreatic necrosis,appropriately selected and sufficiently used antibiotic therapy(if necessary),pain control,adequate hydration,control of haemodynamic parameters and transfer to the Intensive Care Unit(ICU)(if necessary),endoscopic retrograde cholangiopancreatography(ERCP) in biliary AP,surgical treatment(if necessary),and advice on outpatient follow-up after discharge. A comparison of the length of stay with that in other Slovenian hospitals was also ***:There were 139 patients treated in the three-year period after the introduction of a CP,of which 81(58.3%) were male and 58(41.7%) female. The patients' mean age was 59.6 ± 17.3 years. The most common aetiologies were alcoholism and gallstones(38.8% each),followed by unexplained(11.5%),drug-induced,hypertriglyceridemia,post ERCP(2.9% each) and tumours(2.2%). Antibiotic therapy was prescribed in 72(51.8%) patients. Abdominal US was performed in all patients within the first 24 h after admission. Thirty-two(23.0%) patients were treated in the ICU. Four patients died(2.9%). In comparison to 2006-2007,we found an increased number of alcoholic and biliary AP and an associateddecrease in the number of unexplained aetiology cases. The use of antibiotics also significantly decreased after the implementation of a CP(from 70.3% to 51.8%; P = 0.003). There was no statistically

关键词： Acute Pancreatitis Treatment Clinicalpathway Indicator Quality

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Impact of natural disturbance, forest management and vegetation cover on topsoil biochemical characteristics of Tatra Mts.(Slovakia)

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Journal of Mountain Science 2020年第6期17卷 1294-1309页

作者： jana GáFRIKOVá Milan ZVARíK Peter hANAJíK Marek SúLOVSKY Ivana VYKOUKOVá Faculty of Natural Sciences Comenius UniversityBratislava84104Slovak Republic Faculty of Mathematics Physics and InformaticsComenius UniversityBratislava84104Slovak Republic Water Research Institute Bratislava81249Slovak Republic

Perturbations caused by windstorms usually lead to the harvesting and clearcutting of fallen trees and wood debris,especially in the areas of managed forest *** shifts in soils due to management practices play a crucial role in the restoration and maintaining of key ecosystem *** paper focuses on topsoil chemical properties in relation to vegetation type(trees,shrubs and herbs)evolving at windstorm damaged(in 2004)areas with former Norway spruce(Picea abies)forests in the Tatra ***(Slovakia).We assessed the content of topsoil organic matter fractions(extractives,holocellulose(hC)and lignin(Lig)),carbon in microbial biomass(Cmic),soil organic matter(SOM)and the content of elements N,C,h and *** study plots represent different types of post-windthrow disturbance history/regime:wooden debris extraction(EXT),wooden debris not extracted(NEX),wooden debris extraction followed by wildfire(FIR),affected by the windstorm in 2014 with the subsequent wooden debris extraction(REX)and unaffected(REF).Our results revealed significant differences among sites in the content of dichloromethane extractives(EXT *** and FIR),acetone extractives(NEX ***,FIR and REF),ethanol extractives(FIR ***,NEX and REF),water extractives(FIR ***,NEX)and Cmic(EXT ***,FIR and REF).The topsoil of Vaccinium myrtillus and Picea abies showed a higher ratio of C/N,N/Lig,and Lig/hC compared to Rubus idaeus,Avenella flexuosa,Calamagrostis villosa,and Larix *** content of N,C,h and S varied between topsoil with shrubs(Vaccinium myrtillus,Rubus idaeus)and grasses(Avenella flexuosa,Calamagrostis villosa).A positive correlation between soil organic matter(SOM)and polar extractives(r=0.81)and a negative correlation between SOM and hC(r=-0.83)was *** carbon content in microbial biomass(Cmic)is positively correlated with acid soluble lignin(ASL)(r=0.85).We also identified a strong correlation between Klason lignin(KL)and the Lig/hC ratio(r=0.97).

关键词： Windthrow Wildfire Organic matter fractions Vegetation type Norway spruce Topsoil chemical properties

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Fabrication and evaluation of carboxymethyl guar gum-chitosan interpenetrating polymer network (IPN) nanoparticles for controlled drug delivery

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Medicine in Novel Technology and Devices 2024年第2期22卷 73-79页

作者： Chandrani Roy Arijit Gandhi Sreejan Manna Sougata jana Department of Pharmaceutics Gupta College of Technological SciencesAshram MoreG.T.RoadAsansol713301West BengalIndia Department of Pharmaceutical Technology Brainware UniversityBarasatKolkataWest Bengal700125India Department of health and Family Welfare Directorate of Health ServicesKolkataIndia

Guar gum(GG)has drawn more interest from researchers in the last several decades for the controlled delivery of *** aim of the research is to fabricate and evaluate an interpenetrating polymer network(IPN)based nanocarriers system employing chemically modified GG to achieve controlled release of *** present study,we have reported the synthesis of carboxymethyl GG-chitosan IPN nanoparticles for controlled release of metformin *** guar gum(CMGG)was synthesized and employed for developing IPN nanoparticles in combination with chitosan in varying polymeric ratios.A cross-linking agent,sodium tripolyphosphate(Na-TPP)was used for the synthesis of IPN colloidal suspension of nanoparticles which was lyophilized to obtain *** carboxymethylation of GG was confirmed through Fourier transform infra-red spec*** mean particle size was 440.6 nm indicating a polydispersity index of *** drug entrapment efficiency was found to vary between 67.461.64%to 88.232.02%.The differential scanning calorimetry study revealed the presence of amorphous metformin hydrochloride as a homogenous dispersion in nanoparticles(NPs)*** vitro drug release study indicated controlled release ability of developed IPN matrix.A2 formulation(chitosan:CMGG-1:1)exhibited 78.110.27%release after 8 *** evaluation performed in alloxan-treated diabetic rat model exhibited a prolonged hypoglycemic efficacy over 6 h,for A2 formulation treated group,compared to the group receiving only metformin hCl,which demonstrated a reduction in blood glucose levels for up to 4 *** study findings demonstrated the efficacy of the CMGG-chitosan based IPN nanoparticulate system for sustained delivery of therapeutic agents.

关键词： Carboxymethyl guar gum Chitosan Interpenetrating polymer network Nanoparticles Controlled release Metformin hydrochloride

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