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Comparative study of two modeling approaches for predicting heavy metals contaminant migration from polyethylene bags

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International Journal of Agricultural and Biological Engineering 2016年第3期9卷 194-200页

作者： Noble Banadda Fredrick Lule Cornelius Sempala julia Kigozi Department of Agricultural and Bio-Systems Engineering Makerere UniversityUganda Department of Educational Foundations and Curriculum Makerere UniversityUganda

Plasto-Foam brand,medium size of 30 mm thickness(black and green)commonly used polyethylene bags for preparing foods were selected from those available in local *** polyethylene bag samples were crushed into pieces,ashed and then acid digested to determine the concentrations of heavy metals selected(Pb,Cr,Co and Cd)using Atomic Absorption *** the polyethylene samples were tested positive for heavy *** of heavy metals in polyethylene bags ranged from 1080 ppm to 1725 ppm,76 ppm to 112 ppm,35 ppm to 52 ppm,18 ppm to 31 ppm for Pb,Cd,Cr and Co,***-eight posho(Ugali)samples were prepared and wrapped in these polyethylene bags and migration studies were carried out at 65°C and 80°*** experimental data obtained were then compared to the modeled data using the models developed by Baner et al.,and Limm and Hollifield to determine which model was a better *** fitting was done based on Non-linear least square analysis using Microsoft EXCEL *** and partition coefficients both between food and the contact material were also obtained by fitting experimental data to the model *** modeling approaching could best describe the experimental data of the measured *** study revealed that all polyethylene bags showed highest contaminant concentration(above USFDA limit)of Pb,Cd,Cr and Co,respectively confirming the potential health risk to individuals if continuously eat food thermally prepared in polyethylene bags.

关键词： heavy metals polyethylene bags migration mathematical models

Nicotiana attenuata's capacity to interact with arbuscular mycorrhiza alters its competitive ability and elicits major changes in the leaf transcriptome

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Journal of Integrative Plant Biology 2018年第3期60卷 242-261页

作者： Ming Wang julia Wilde Ian T.Baldwin Karin Groten Department of Molecular Ecology Max Planck Institute for Chemical EcologyHans-Knoll-Str.8Jena 07745Germany

To study the local and systemic effects of arbuscular mycorrhizal fungal （AMF） colonization, Nicotiana attenuata plants impaired in their interactions with AMF due to silencing of a calcium- and calmodulin dependent protein kinase （inverted repreat （ir）CCaMK） were grown competitively in pairs with empty vector （EV） plants, with and without two different types of inoculum. When inoculated, EV plants strongly outperformed irCCaMK plants. Foliar transcript profiling revealed that AMF colonization significantly changed gene expression of P-starvation and -transporter genes in irCCaMK plants. The Phtl family phosphate transporter NaPT5 was not only specifically induced in roots after AMF colonization, but also in leaves of AMF-colonized irCCaMK plants, and in plants grown under low Pi conditions in the absence of AMF. The P-starvation signature of inoculated irCCaMK plants corresponded with increases in selected amino acids and phenolic compounds in leaves. We also found a strong AMF-induced increase in amino acids and phenolic metabolites in roots. Plants impaired in their interactions with AMF clearly have a fitness disadvantage when competing for limited soil nutrients with a fully functional isogenic line. The additional role of the AMF-induced Phtl family transporter NaPT5 in leaves under P-starvation conditions will require further experiments to fully resolve.

关键词： William J. Lucas University of California Davis USA

High-performance Li-S battery cathode with catalyst-like carbon nanotube-MoP promoting polysulfide redox

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Nano Research 2017年第11期10卷 3698-3705页

作者： Yingying Mi Wen Liu Xiaolin Li julia Zhuang Henghui Zhou Hailiang Wang Department of Chemistry and Energy Sciences Institute Yale University West Haven CT 06516 USA College of Chemistry and Molecular Engineering Peking University Beijing 100871 China College of Chemistry and Chemical Engineering Chongqing University Chongqing 400044 China Department of Chemical and Environmental Engineering Yale University New Haven CT 06520 USA

Despite promising characteristics such as high specific energy and low cost,current Li-S batteries fall short in cycle *** the cycling stability of S cathodes requires immobilizing the lithium polysulfide （LPS） intermediates as well as accelerating their redox *** many materials have been explored for trapping LPS,the ability to promote LPS redox has attracted much less ***,we report for the first time on transition metal phosphides as effective host materials to enhance both LPS adsorption and *** MoP-nanoparticle-decorated carbon nanotubes with S deposited on graphene oxide,we enable Li-S battery cathodes with substantially improved cycling stability and rate *** decay rates as low as 0.017% per cycle over 1,000 cycles can be *** and high areal capacity （〉 3 mAh＆#183;cm-2） can be achieved under high mass loading *** electrochemical performance can also be achieved with analogous material structures based on CoP,demonstrating the potential of metal phosphides for long-cycle Li-S batteries.

关键词： lithium-sulfur battery metal phosphide lithium polysulfide long cycle

Annual Time-series Analyses of Total Gaseous Mercury Measurement and its Impact Factors on the Gongga Mountains in the Southeastern Fringe of the Qinghai-Tibetan Plateau

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Journal of Mountain Science 2008年第1期5卷 17-31页

作者： ZHU Wanze FU Xuewu FENG Xinbin julia Y. Lu Institute of Mountain Hazard and Environment Chinese Academy of Sciences Chengdu 610041 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Department of Chemistry and Biology Ryerson University Toronto Ontario M5B 2K3 Canada

Long-term monitoring programs for measurement of atmospheric mercury concentrations are presently recognized as powerful tools for local,regional and global studies of atmospheric long-range transport processes,and they could also provide valuable information about the impact of emission controls on the global budget of atmospheric mercury,their observance and an insight into the global mercury cycle. China is believed to be an increasing atmospheric mercury emission source. However,only a few measurements of mercury,to our knowledge,have been done in ambient air over China. The highly-time resolved atmospheric mercury concen-trations have been measured at Moxi Base Station (102°72′E 29°92′N,1640 m asl) of the Gongga Alpine Ecosystem Observation and Experiment Station of Chinese Academy of Sciences (CAS) from May 2005 to June 2006 by using a set of Automatic Atmospheric Mercury Speciation Analyzers (Tekran 2537A). Measurements were carried out with a time resolution of every 15 minutes. The overall average total gaseous mercury (TGM) covering the measurement periods was 4±1.38 ng·m-3 (N=57310),which is higher than the global background level of approximately 1.5～2.0 ng·m-3. The measurements in all seasons showed a similar diurnal change pattern with a high concentration during daytime relative to nighttime and maximum concentration near solar noon and minimum concentration immediately before sunrise. The presence of diurnal TGM peaks during spring and summer was found earlier than that during autumn and winter. When divided seasonally,it was found that the concentrations of TGM were highest in winter with 6.13 ± 1.78 ng·m-3 and lowest in summer with 3.17 ± 0.67 ng·m-3. There were no significant differences in TGM among wind sectors during each season. Whereas Hg generally exhibited significant correlations with the parameters,such as temperature,saturated vapor pressure,precipitation,ultraviolet radiation (UV) and atmospheric pressure at the whole measurement stage,

关键词： Total gaseous mercury (TGM) diurnal variability seasonal variability meteorological factor Gongga Mountains

pH-dependent leaching behaviour and other performance properties of cement-treated mixed contaminated soil

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Journal of Environmental Sciences 2012年第9期24卷 1630-1638页

作者： Reginald B. Kogbara Abir Al-Tabbaa Yaolin Yi julia A. Stegemann Geotechnical and Environmental Group Cambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UK. Center of ExceUence in Environmental Studies King Abdulaziz University Jeddah 21589 Saudi Arabia Institute of Geotechnical Engineering Southeast University 2# Sipailou Nanjing 210096 China Department of Civil Environmental and Geomatic Engineering Chadwick Building University College London WCIE 6BT UK

Portland cement has been widely used for stabilisation/solidification （S/S） treatment of contaminated soils. However, there is a dearth of literature on pH-dependent leaching of contaminants from cement-treated soils. This study investigates the leachability of Cu, Pb, Ni, Zn and total petroleum hydrocarbons （TPH） from a mixed contaminated soil. A sandy soil was spiked with 3000 mg/kg each of Cd, Cu, Pb, Ni and Zn, and 10,000 mg/kg of diesel, and treated with ordinary Portland cement （CEM I）. Four different binder dosages, 5%, 10%, 15% and 20% （m/m） and different water contents ranging from 13%-19% dry weight were used in order to find a safe operating envelope for the treatment process. The pH-dependent leaching behaviour of the treated soil was monitored over an 84-day period using a 3-point acid neutralisation capacity （ANC） test. The monolithic leaching test was also conducted. Geotechnical properties such as unconfined compressive strength （UCS）, hydraulic conductivity and porosity were assessed over time. The treated soils recorded lower leachate concentrations of Ni and Zn compared to the untreated soil at the same pH depending on binder dosage. The binder had problems with Pb stabilisation and TPH leachability was independent of pH and binder dosage. The hydraulic conductivity of the mixes was generally of the order, 10-8 m/sec, while the porosity ranged from 26%--44%. The results of selected performance properties are compared with regulatory limits and the range of operating variables that lead to acceptable performance described.

关键词： diesel heavy metals hydraulic conductivity porosity Portland cement stabilisation/solidification

Machine-learned metrics for predicting the likelihood of success in materials discovery

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npj Computational Materials 2020年第1期6卷 539-547页

作者： Yoolhee Kim Edward Kim Erin Antono Bryce Meredig julia Ling Citrine Informatics Redwood CityCA 94063USA

Materials discovery is often compared to the challenge of finding a needle in a *** much work has focused on accurately predicting the properties of candidate materials with machine learning(ML),which amounts to evaluating whether a given candidate is a piece of straw or a needle,less attention has been paid to a critical question:are we searching in the right haystack?We refer to the haystack as the design space for a particular materials discovery problem(i.e.,the set of possible candidate materials to synthesize),and thus frame this question as one of design space *** this paper,we introduce two metrics,the predicted fraction of improved candidates(PFIC),and the cumulative maximum likelihood of improvement(CMLI),which we demonstrate can identify discovery-rich and discovery-poor design spaces,respectively.A combined classification system,composed of the CMLI and PFIC metrics,is then used to identify optimal design spaces with high precision,and thus show the potential to significantly accelerate ML-driven materials discovery.

关键词： likelihood predicting searching

From Tpex to Tex: a journey through CD8^(+) T cell responses in cancer immunotherapy

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Signal Transduction and Targeted Therapy 2023年第10期8卷 4419-4420页

作者： julia M.Messmer Maike Effern Michael Holzel Institute of Experimental Oncology University Hospital BonnUniversity of Bonn53127BonnGermany

In a recent study published in Cell,Rahim et *** that a subset of progenitor exhausted CD8+T cells(Tpex)in uninvolved,regional lymph nodes(uiLNs)are clonally related to exhausted CD8^(+)T cells(Tex)in tumors of patients with head and neck squamous cell carcinoma(HNSCC)and following adjuvant immune checkpoint blockade(ICB)these clones expanded in the tumor suggestive of migration from the uiLNs and differentiation into an exhaustion state.1 The work by Rahim et *** the great value of neoadjuvant ICB clinical trials to better understand the dynamics of T cell responses in patients.

关键词： al. Tpe patients

Alcohol consumption in non-alcoholic fatty liver disease—harmful or beneficial?

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Hepatobiliary Surgery and Nutrition 2019年第3期8卷 311-313页

作者： Stergios Kechagias julia Blomdahl Mattias Ekstedt Department of Medical and Health Sciences Linkoping UniversityLinkopingSweden

Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease with an estimated global prevalence of 25%.Approximately 5%of NAFLD patients have cirrhosis and currently NAFLD is the second most common etiology among adults awaiting liver transplant in the United *** the Western world alcohol overconsumption is the leading cause for advanced decompensated liver disease but whether moderate alcohol consumption,compatible with the diagnosis of NAFLD,plays a role for development of liver-related complications in NAFLD is *** NAFLD entails a clinically significant risk for encountering complications of advanced liver disease,cardiovascular disease(CVD)is the leading cause of mortality and morbidity among subjects with *** and CVD share many common risk factors,for instance components of the metabolic *** has been reported that modest alcohol consumption is associated with beneficial effects on risk of metabolic syndrome and insulin resistance,which are crucial for the development and progression of NAFLD.

关键词： diagnosis mortality alcohol

Natural history of children with mild Crohn’s disease

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World Journal of Gastroenterology 2019年第30期25卷 4235-4245页

作者： Yamini Sharma Athos Bousvaros Enju Liu julia Bender Stern Department of Gastroenterology and Hepatology Inflammatory Bowel Disease Center Boston Children’s Hospital

BACKGROUND There is a small and poorly studied population of patients with mild and limited Crohn’s disease(CD),who either spontaneously enter remission and can discontinue therapy,or be maintained on milder anti-inflammatory *** To identify a group of children with mild CD who were not escalated to immunomodulators(azathioprine,mercaptopurine,or methotrexate)or biologics(infliximab or adalimumab)within the first two years after their Crohn’s diagnosis and outline the natural history and phenotypic features of these *** In a retrospective chart review of the inflammatory bowel disease database at Boston Children’s Hospital we reviewed all the mild CD patient’s clinic visits,laboratory studies,and procedures for the duration of time they were followed at the *** were included if they had clear diagnosis of Crohn’s disease,and they were not escalated to immunosuppressive therapies for at least 2 years after the date of *** mild CD patients were compared to controls diagnosed at a similar time,that were treated with immunomodulators or *** that was abstracted included:Age at diagnosis,sex,disease location utilizing the Paris classification,medical treatment,surgical treatment,endoscopic findings,histology,and *** also analyzed differences in the phenotypic features between those with mild CD and those with moderate to severe *** Out of 1205 patients with CD diagnosed between 1990 and 2013,we identified 29 patients that met the inclusion criteria,and they were matched with 58 *** were no significant differences between the disease behaviors at presentation,with approximately 90%of patients in each group having inflammatory ***,patients with mild disease were more likely to have disease limited to the colon(31%vs 12%,P=0.03).In contrast,patients with moderate to severe disease(aka control group)were more likely to have ileocolonic disease(70%vs 45%in the mild grou

关键词： Crohn’s disease Colitis Aminosalicylates Antibiotics Immunosuppression Inflammatory bowel disease Child Pediatric