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Characterization of soil fauna under the influence of mercury atmospheric deposition in Atlantic Forest, Rio de janeiro, Brazil

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journal of Environmental Sciences 2015年第6期27卷 217-227页

作者： Andressa Cristhy Buch Maria elizabeth Fernandes Correia Daniel Cabral Teixeira Emmanoel Vieira Silva-Filho Departamento de Geoquímica Universidade Federal Fluminense Embrapa Agrobiologia BR 465 km 7

The increasing levels of mercury（Hg） found in the atmosphere arising from anthropogenic sources, have been the object of great concern in the past two decades in industrialized countries. Brazil is the seventh country with the highest rate of mercury in the *** major input of Hg to ecosystems is through atmospheric deposition（wet and dry）, being transported in the atmosphere over large distances. The forest biomes are of strong importance in the atmosphere/soil cycling of elemental Hg through foliar uptake and subsequent transference to the soil through litter, playing an important role as sink of this element. Soil microarthropods are keys to understanding the soil ecosystem, and for such purpose were characterized by the soil fauna of two Units of Forest Conservation of the state of the Rio de janeiro, inwhich one of the areas suffer quite interference from petrochemicals and industrial anthropogenic activities and other area almost exempts of these perturbations. The results showed that soil and litter of the Atlantic Forest in Brazil tend to stock high mercury concentrations, which could affect the abundance and richness of soil fauna, endangering its biodiversity and thereby the functioning of ecosystems.

关键词： Biodiversity Litter Microarthropods Soil Trace-element

Spatial Distribution of Mountain Pine Beetle Outbreaks in Relation to Climate and Stand Characteristics： A Dendroecological Analysis

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journal of Integrative Plant Biology 2007年第2期49卷 168-178页

作者： elizabeth M. Campbell René I. Alfaro Brad Hawkes Canadian Forest Service Pacific Forestry Centre Victoria BC Canada V8Z 1M5

Principal components analysis, followed by K-means cluster analysis, was used to detect variations in the timing and magnitude of Pinus contorta Dough ex Loud. growth releases attributed to mountain pine beetle outbreaks in 31 stands of central British Columbia. Four major growth release patterns were identified from 1970 to 2000. Variations in the timing of growth releases among clustered stands corresponded well to aerial survey data indicating the timing of beetle outbreaks in the study area. Redundancy analysis was used to determine how variations in the timing and magnitude of growth releases attributed to beetle outbreaks changed with variations in climate or stand conditions over the study area. The first RDA axis, which accounted for 39% of the variations in growth patterns among stands, was significantly （P〈0.05） correlated with gradients in the percentage of pine in stands killed by mountain pine beetle, summer aridity, variation in summer precipitation, distance from initial infestation site, average pine age, and maximum August temperatures. The second RDA axis explained 6% of the variations and was significantly correlated with gradients in the beetle climate suitability index, extreme cold month temperatures, and site index. Comparisons of growth release patterns with aerial survey data and redundancy analyses indicated that dendrochronological techniques are useful for identifying mountain pine beetle outbreaks in central British Columbia, particularly among stands that had a density high enough to produce a growth release signal. Provided future studies account for interannual weather fluctuations, identification of growth increases due to stand thinning caused by beetle outbreaks will be useful for reconstructing the history of beetle outbreaks over much longer time periods.

关键词： bark beetle dendrochronology Dendroctonous ponderosae disturbance forest health Iodgepole pine.

Lipolysis supports bone formation by providing osteoblasts with endogenous fatty acid substrates to maintain bioenergetic status

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Bone Research 2023年第4期11卷 876-894页

作者： Ananya Nandy Ron C.M.Helderman Santosh Thapa Shobana jayapalan Alison Richards Nikita Narayani Michael P.Czech Clifford j.Rosen elizabeth Rendina-Ruedy Department of Medicine Division of Clinical PharmacologyVanderbilt University Medical CenterNashvilleTN 37232USA Program in Molecular Medicine University of Massachusetts Chan Medical SchoolWorcesterMA 01605USA Maine Medical Center Research Institute ScarboroughMEUSA Molecular Physiology and Biophysics Vanderbilt UniversityNashvilleTN 37232USA

Bone formation is a highly energy-demanding process that can be impacted by metabolic *** has been considered the principal substrate for osteoblasts,although fatty acids are also important for osteoblast ***,we report that osteoblasts can derive energy from endogenous fatty acids stored in lipid droplets via lipolysis and that this process is critical for bone *** such,we demonstrate that osteoblasts accumulate lipid droplets that are highly dynamic and provide the molecular mechanism by which they serve as a fuel source for energy generation during osteoblast *** cytoplasmic lipolysis leads to both an increase in lipid droplet size in osteoblasts and an impairment in osteoblast *** fatty acids released by lipolysis from these lipid droplets become critical for cellular energy production as cellular energetics shifts towards oxidative phosphorylation during nutrient-depleted *** vivo,conditional deletion of the ATGL-encoding gene Pnpla2 in osteoblast progenitor cells reduces cortical and trabecular bone parameters and alters skeletal lipid ***,our data demonstrate that osteoblasts store fatty acids in the form of lipid droplets,which are released via lipolysis to support cellular bioenergetic status when nutrients are *** in this process result in impairment of bone formation,specifically reducing ATP production and overall osteoblast function.

关键词： endogenous maintain osteoblast

Effects of polydimethylsiloxane membrane surface treatments on human uterine smooth muscle cell strain response

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Bioactive Materials 2024年第2期32卷 415-426页

作者： elizabeth E.Marr Brett C.Isenberg joyce Y.Wong Boston University Division of Materials Science and EngineeringUnited States Charles Stark Draper Laboratory Bioengineering DivisionUnited States Boston University Department of Biomedical EngineeringUnited States

In the United States,1 in 10 infants are born *** majority of neonatal deaths and nearly a third of infant deaths are linked to preterm *** birth is initiated when the quiescent state of the uterus ends prematurely,leading to contractions and parturition beginning as early as 32 weeks,though the origins are not well *** enable research and discovery of therapeutics with potential to better address preterm birth,the capability to study isolated cell processes of pregnant uterine tissue in vitro is *** development of an in vitro model of the myometrium utilizing human uterine smooth muscle cells(uSMCs)responsible for contractions provides a methodology to examine cellular mechanisms of late-stage pregnancy potentially involved in preterm *** discuss culture of uSMCs on a flexible polydimethylsiloxane(PDMS)substrate functionalized with cationic poly-L-lysine(PLL),followed by extracellular matrix(ECM)protein *** work exploring uSMC behavior on PDMS substrates have utilized collagen-I coatings,however,we demonstrated the first exploration of human uSMC response to strain on fibronectin-coated flexible membranes,importantly reflecting the significant increase of fibronectin content found in the myometrial ECM during late-stage *** the model we developed,we conducted proof-of-concept studies to investigate the impact of substrate strain on uSMC cell morphology and gene *** was found that PLL and varied ECM protein coatings(collagen I,collagen III,and fibronectin)altered cell nuclei morphology and density on PDMS ***,varied strain rates applied to uSMC substrates significantly impacted uSMC gene expression of IL-6,a cytokine associated with instances of preterm *** results suggest that both surface and mechanical properties of in vitro systems impact primary human uSMC phenotype and offer uSMC culture methodologies that can be utilized to further the understanding of cellu

关键词： Uterine Myometrium Bioengineered in vitro models Strain Pregnancy Nuclei Interleukin 6 Preterm labor

Optimization of wheat debranning using laboratory equipment for ethanol production

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International journal of Agricultural and Biological Engineering 2014年第6期7卷 54-66页

作者： elizabeth George Bayartoghtok Rentsen Lope G.Tabil Venkatesh Meda Department of Chemical and Biological Engineering University of SaskatchewanSaskatoonSK S7N 5A9Canada

Ethanol production from starchy cereal grains is increasing rapidly due to increasing demand for alternative *** Canada,wheat is the primary feedstock in ethanol *** improve the productivity of the ethanol plants in terms of product quality and yield,debranning of wheat grains may be *** is advantageous in two ***,bran removal increases the starch content of the feedstock,improving the fermentation efficiency of the ethanol ***,bran,a valuable co-product can be used as an animal feed *** this study,experiments to optimize the debranning process were carried out using two kinds of abrasive equipment,the Satake and the TADD(tangential abrasive dehulling device)*** samples(30 and 200 g)were debranned in the Satake mill at 1215,1412,and 1515 r/min rotational speeds,30,36,and 40 grit sizes,and 30,60,and 90 s retention times,and in the TADD mill at 900 r/min rotational speed,30,36,50,and 80 grit sizes,and 120,180,240,and 300 s retention *** addition to debranning efficiency,the starch separation efficiencies of the two mills were calculated in different debranning *** the Satake mill,the 30 g and 200 g sample size,1412 r/min and 1515 r/min rotational speeds,all grit sizes,and 60 s of retention time demonstrated the highest debranning ***,optimal results in the TADD mill were obtained with 200 g sample size,900 r/min rotational speed,50 and 80 grit sizes,and 180 s and 240 s retention ***,based on the experimental results,Satake mill provided better debranning values compared to the TADD *** starch separation efficiency values supported these results.

关键词： wheat debranning ethanol production Satake mill tangential abrasive dehulling device grit size retention time rotational speed starch separation efficiency

Immune response differences in degradable and non-degradable alloy implants

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Bioactive Materials 2023年第6期24卷 153-170页

作者： Taravat Khodaei elizabeth Schmitzer Abhirami P.Suresh Abhinav P.Acharya Biomedical Engineering School of Biological and Health System EngineeringArizona StateUniversityTempeAZ85281USA Biological Design Arizona State UniversityTempeAZ85281USA Chemical Engineering School for the Engineering of MatterTransportand EnergyArizona StateUniversityTempeAZ85281USA Materials Science and Engineering School for the Engineering of MatterTransportand EnergyArizona State UniversityTempeAZ85281USA Center for Immunotherapy Vaccines and VirotherapyArizona State UniversityTempeAZ85281USA

Alloy based implants have made a great impact in the clinic and in preclinical *** responses are one of the major causes of failure of these implants in the *** the immune responses toward non-degradable alloy implants are well documented,there is a poor understanding of the immune responses against degradable alloy ***,there have been several reports suggesting that degradable implants may develop substantial immune *** phenomenon needs to be further studied in detail to make the case for the degradable implants to be utilized in ***,we review these new recent reports suggesting the role of innate and potentially adaptive immune cells in inducing immune responses against degradable ***,we discussed immune responses to allergen components of non-degradable implants to give a better overview on differences in the immune response between non-degradable and degradable ***,we also provide potential areas of research that can be undertaken that may shed light on the local and global immune responses that are generated in response to degradable implants.

关键词： alloy utilized implants

Senescent human hepatocytes express a unique secretory phenotype and promote macrophage migration

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World journal of Gastroenterology 2014年第47期20卷 17851-17862页

作者： Katharine M Irvine Richard Skoien Nilesh j Bokil Michelle Melino Gethin P Thomas Dorothy Loo Brian Gabrielli Michelle M Hill Matthew j Sweet Andrew D Clouston elizabeth E Powell Centre for Liver Disease Research School of MedicineThe University of QueenslandTranslational Research InstituteBrisbane 4102Australia Institute for Molecular Bio-science The University of QueenslandBrisbane 4067Australia The University of Queensland Diamantina Institute The University of Queensland Translational Research InstituteBrisbane 4102Australia Department of Gastroenterology and Hepatology Princess Alexandra HospitalBrisbane 4102Australia

AIM: To develop a model of stress-induced senescence to study the hepatocyte senescence associated secretory phenotype (SASP).

关键词： Cell aging Chemokines Hepatocytes Inflammation Liver diseases Macrophages

Differential effects of energy balance on experimentally-induced colitis

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World journal of Gastroenterology 2012年第7期18卷 627-636页

作者： Sarah j McCaskey elizabeth A Rondini Ingeborg M Langohr jenifer I Fenton Department of Food Science and Human Nutrition Michigan State UniversityEast LansingMI 48824United States Department of Pathobiology and Diagnostic Investigation Michigan State UniversityEast LansingMI 48824United States College of Osteopathic Medicine Michigan State UniversityEast LansingMI 48824United States

AIM： To characterize the influence of diet-induced changes in body fat on colitis severity in SlVlAD3-/- mice.METHODS： SMAD3-/- mice （6-8 wk of age） were ran- domly assigned to receive a calorie restricted （30% of control; CR）, control （CON）, or high fat （HF） diet for 20 wk and were gavaged with sterile broth or with Helicobacter hepaticus （H. hepaticus） to induce colitis. Four weeks after infection, mice were sacrificed and the cecum and colons were processed for histological evaluation.RESULTS： Dietary treatment significantly influenced body composition prior to infection （P 〈 0.05）, with CR mice having less （14%±2%） and HF-fed mice more body fat （32% ± 7%） compared to controls （22%±4%）. Differences in body composition were associated with alterations in plasma levels of leptin （HF 〉 CON 〉 CR） and adiponectin （CON 〉 HF 〉/ CR）（P 〈 0.05）. There were no significant differences in colitis scores between CON and HF-fed mice 4 wk post-infection. Consistent with this, differences in proliferation and in- flammation markers （COX-2, iNOS）, and infiltrating cell types （CD3^＋ T lymphocytes, macrophages） were not observed. Unexpectedly, only 40% of CR mice survived infection with H. hepaticus, with mortality observed as early as I wk following induction of colitis.CONCLUSION： Increased adiposity does not influence colitis severity in SMAD3-/- mice. Importantly, caloric restriction negatively impacts survival following pathogen challenge, potentially due to an impaired immune response.

关键词： SMAD3 Colitis Adipokine Obesity Calorierestriction

Anxiety Symptoms Questionnaire(ASQ):development and validation

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General Psychiatry 2019年第6期32卷 335-345页

作者： Amanda Baker Naomi Simon Aparna Keshaviah Amy Farabaugh Thilo Deckersbach john j Worthington elizabeth Hoge Maurizio Fava Mark P Pollack Massachusetts General Hospital BostonMassachusettsUSA Harvard Medical School BostonMassachusettsUSA New York University Medical Center New YorkNew YorkUSA Georgetown University Medical Center WashingtonDistrict of ColumbiaUSA Rush University Medical Center ChicagoIllinoisUSA

Background The Anxiety Symptoms Questionnaire(ASQ)is a brief self-report questionnaire which measures frequency and intensity of symptoms and was developed to improve assessment of anxiety symptoms in a clinical *** examined the reliability and validity of the ASQ in patients with anxiety disorders and/or depression,nonclinical control subjects and college *** 240 outpatients with generalised anxiety disorder,social anxiety disorder,panic disorder or major depressive disorder were administered the ASQ and additional questionnaires measuring depression and anxiety,as were 111 non-clinical control subjects and 487 college *** analysis,Pearson's correlation coefficients and logistic regression were used to assess reliability and ***-retest reliability of the ASQ was measured using a subset who were re-administered the ASQ after 4 *** Factor analysis revealed measurement of a single dimension by the *** consistency and test-retest reliability were *** ASQ total score also significantly distinguished patients with an anxiety disorder from the clinical controls above and beyond the clinicianrated Hamilton Anxiety *** The ASQ is a valid,reliable and effective self-rated measure of anxiety and may be a useful tool for screening and assessing anxiety symptoms in psychiatric as well as college settings.

关键词： clinical ASQ validity