检索结果-南通市图书馆

Repeated hydrogen peroxide dosing briefly reduces cyanobacterial blooms and microcystin while increasing fecal bacteria indicators in a eutrophic pond

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第2期124卷 522-543页

作者： mark W.lusty Christopher J.Gobler School of Marine and Atmospheric Sciences Stony Brook UniversitySouthamptonNY 11968USA

This study explored the effects of H_(2)O_(2)on Cyanobacteria and non-target microbes using fluorometry,microscopy,flow cytometry,and high throughput DNA sequencing of the 16S rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY,*** addition of H_(2)O_(2)(8 mg/l)significantly reduced Cyanobacteria concentrations during a majority of experiments(66%;6 of 9)and significantly increased eukaryotic green and unicellular brown algae in 78%and 45%of experiments,*** heterotrophic bacteria declined significantly following H_(2)O_(2)addition in all experiments,bacteria indicative of potential fecal contamination(Escherichia coli,Enterococcus,fecal coliform bacteria)consistently and significantly increased in response to H_(2)O_(2),evidencing a form of‘pollution swapping’.H_(2)O_(2)more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem *** whole-pond H_(2)O_(2)applications over a twoyear period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or *** bacterial phyla of Cyanobacteria,Actinobacteria,and Planctomycetes were the most negatively impacted by H_(2)O_(2).Microcystis was always reduced by H_(2)O_(2),as was the toxin microcystin,but Microcystis remained dominant even after repeated H_(2)O_(2)*** H_(2)O_(2)favored the growth of eukaryotic algae over potentially harmful Cyanobacteria,the inability of H_(2)O_(2)to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination.

关键词： Indicator bacteria Toxic cyanobacteria Microcystin Microcystis Hydrogen peroxide Bacteria Enterococcus E.coli Pollution swapping

Hepcidin levels in hereditary hyperferritinemia:Insights into the iron-sensing mechanism in hepatocytes

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2010年第28期16卷 3541-3545页

作者： Jayantha Arnold Arvind Sangwaiya Vijay Manglam mark Thursz Caroline Beaumont Caroline Kannengiesser mark Busbridge Department of Gastroenterology Ealing HospitalLondonUB1 3HWUnited Kingdom Department of Hepatology St Mary's Hospital Imperial College LondonLondonW2 1NYUnited Kingdom Biochemical hormones and Genetics laboratory Bichat Claude Bernard Hospital46Rue Henri HuchardParis75018France Clinical Chemistry Hammersmith Hospital Imperial College LondonLondonW6 8RFUnited Kingdom

AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the l-ferritin gene,were recruited to undergo serum hepcidin and prohepcidin measurements using radioimmunoassay and enzyme linked immunoassay,respectively,and measurements were compared with levels in serum from 25 healthy volunteers(14 females),mean age 36±11.9 ***:The serum hepcidin and prohepcidin levels in patients with HHCS were 19.1±18.6 and 187± 120.9 ng/ml,*** ferritin was 1716.3± 376μg/*** biopsy in one patient did not show any evidence of iron *** hepcidin and prohepcidin values in healthy controls(HCs)were 15.30±15.71 and 236.88±83.68 ng/ml,respectively,while serum ferritin was 110±128.08μg/*** was no statistical difference in serum hepcidin level between the two cohorts(19.1±18.6 ng/ml vs 15.30±15.71 ng/ml,P= 0.612)using two-tailed t-test. CONClUSION:Serum hepcidin levels in HHCS patients is similar to that in *** study suggests that circulating ferritin is not a factor influencing hepcidin synthesis and does not have a role in the iron-sensing mechanism in hepatocytes.

关键词： Hereditary hyperferritinemia Hereditary hyperferritinemia cataract syndrome Hepcidin Hepcidin assay Iron-sensing mechanism Iron responsive element Ferritin

Epidemiology of injuries in male and female youth football players:A systematic review and meta-analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2022年第6期11卷 681-695,F0003页

作者： Francisco Javier Robles-Palazón Alejandro lópez-Valenciano mark De Ste Croix Jon l.Oliver Alberto García-Gómez Pilar Sainz de Baranda Francisco Ayala Department of Physical Activity and Sport Faculty of Sport SciencesCampus of Excellence Mare NostrumUniversity of MurciaMurcia 30720Spain Centre for Sport Studies King Juan Carlos UniversityMadrid 28933Spain School of Sport and Exercise University of GloucestershireGloucester GL29HWUK Youth Physical Development Centre School of Sport and Health SciencesCardiff Metropolitan UniversityCardiff CF236XDUK Sport Performance Research Institute New Zealand(SPRINZ) Auckland University of TechnologyAuckland 0632New Zealand Operative Research Centre Miguel Hernández University of ElcheElche 03202Spain

Background:To conduct a systematic review and meta-analysis of epidemiological data of injuries in male and female youth football ***:Searches were performed in MEDlINE/PubMed,Web of Science,Cochrane library,and SPORTDiscus *** were considered if they reported injury incidence rate in male and female youth(≤19 years old)football *** reviewers(FJRP and AlV)extracted data and assessed trial quality using the Strengthening the Reporting of Observational Studies in Epidemiology(STROBE)statement and the Newcastle Ottawa *** Grading of Recommendations Assessment,Development,and Evaluation approach determined the quality of *** were combined using a Poisson random effects regression ***:Forty-three studies were *** overall incidence rate was 5.70 injuries/1000 h in males and 6.77 injuries/1000 h in *** injury incidence(14.43 injuries/1000 h in males and 14.97 injuries/1000 h in females)was significantly higher than training injury incidence(2.77 injuries/1000 h in males and 2.62 injuries/1000 h in females).The lower extremity had the highest incidence rate in both *** most common type of injury was muscle/tendon for males and joint/ligament for *** injuries were the most common in both *** incidence rate of injuries increased with advances in chronological age in *** male players presented higher match injury incidence than sub-elite *** females,there was a paucity of data for comparison across age groups and levels of ***:The high injury incidence rates and sex differences identified for the most common location and type of injury reinforce the need for implementing different targeted injury-risk mitigation strategies in male and female youth football players.

关键词： Incidence Muscle injuries Severity Soccer Young athletes

Anatomical correlates of blepharospasm

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Translational Neurodegeneration 2012年第1期1卷 92-98页

作者： Silvina G Horovitz Anastasia Ford Muslimah Ali Najee-ullah John l Ostuni mark Hallett Human Motor Control Section Medical Neurology BranchNational Institute of Neurological Disorders and Stroke10 Center DriveBdg10/7D37BethesdaMDUSA Brain Rehabilitation Research Center Malcom Randall VA Medical CenterGainesvilleFLUSA Department of Psychology University of FloridaGainesvilleFLUSA Office of the Clinical Director National Institute of Neurological Disorders and StrokeBethesdaMDUSA.

Background:Focal dystonia is a neurological disorder characterized by unwanted muscle *** is a focal dystonia producing an involuntary closure of the *** etiology is ***:To investigate if there are structural changes in the white and grey matter of blepharospasm patients,and if the changes are related to disease ***:T1 and diffusion-weighted magnetic resonance imaging scans were collected from 14 female blepharospasm patients and 14 healthy matched *** matter volumes,fractional anisotropy(FA),and mean diffusivity maps were compared between the *** on grey matter differences within the facial portion of the primary motor cortex,the corticobulbar tract was traced and compared between ***:Changes in grey matter in patients included the facial portion of the sensorimotor area and anterior cingulate *** changes did not correlate with disease *** tract volume and peak tract connectivity were decreased in patients compared with *** were no significant differences in FA or mean diffusivity between ***:Grey matter changes within the primary sensorimotor and the anterior cingulate cortices in blepharospasm patients may help explain involuntary eyelid closure and the abnormal sensations often reported in this condition.

关键词： Blepharospasm Dystonia Volumetric MRI Magnetic resonance imaging Diffusion weighted imaging

ICC density predicts bacterial overgrowth in a rat model of post-infectious IBS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2010年第29期16卷 3680-3686页

作者： Sam-Ryong Jee Walter Morales Kimberly low Christopher Chang Amy Zhu Venkata Pokkunuri Soumya Chatterjee Edy Soffer Jeffrey l Conklin mark Pimentel GI Motility Program Division of GastroenterologyCedars-Sinai Medical Center

AIM:To investigate the interstitial cells of Cajal(ICC) number using a new rat ***:Sprague-Dawley rats were assigned to two *** first group received gavage with Campylobacter jejuni(***) *** second group was gavaged with *** months after clearance of Campylobacter from the stool,precise segments of duodenum,jejunum,and ileum were ligated in self-contained loops of bowel that were preserved in anaerobic *** muscular plexus ICC(DMP-ICC) were quantified by two blinded readers assessing the tissue in a random,coded *** number of ICC per villus was compared among controls,Campylobacter recovered rats without small intestinal bacterial overgrowth(SIBO),and Campylobacter recovered rats with ***:Three months after recovery,27% of rats gavaged with *** had *** rats with SIBO had a lower number of DMP-ICC than controls in the jejunum and *** there appeared to be a density threshold of 0.12 DMP-ICC/villus that was associated with *** ileal density of DMP-ICC was llus,54% of rats had SIBO compared to 9% among ileal sections with > 0.12(Pllus in more than one location of the bowel,88% of these had SIBO compared to 6% in those who did not(PlUSION:In this post-infectious rat model,the development of SIBO appears to be associated with a reduction in *** study of this rat model might help understand the pathophysiology of postinfectious irritable bowel syndrome.

关键词： Post-infectious irritable bowel syndrome Bacterial overgrowth Interstitial cells of Cajal Campylobacter

The Ornithodolite as a tool to quantify animal space use and habitat selection: a case study with birds diving in tidal waters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Integrative Zoology 2019年第1期14卷 4-16页

作者： Emma-louise COlE James J WAGGITT Anders HEDENSTROM Marco PIANO mark D.HOlTON luca BÖRGER Emily l.C.SHEPARD Department of Biosciences Swansea UniversitySwanseaUK School of Ocean Sciences Bangor UniversityMenai BridgeUK Department of Biology Lund UniversityEcology BuildingSweden Centre for Applied Marine Sciences Bangor UniversityMenai BridgeUK

Animal-attached technologies can be powerful means to quantify space use and behavior;however,there are also ethical implications associated with capturing and instrumenting ***,tagging approaches are not necessarily well-suited for examining the movements of multiple individuals within specific,local areas of ***,we assess a method of quantifying animal space use based on a modified theodolite with an inbuilt laser *** a database of>4200 tracks of migrating birds,we show that detection distance in-creases with bird body mass(range 5 g to>10 kg).The maximum distance recorded to a bird was 5500 m and measurement error was≤5 m for targets within this distance range:a level comparable to methods such as GPS *** go on to present a case study where this method was used to assess habitat selection in seabirds operating in dynamic coastal waters close to a tidal *** positional data with outputs from a hydrographic model revealed that great cormorants(Phalacrocorax carbo)appeared to be highly selective of current characteristics in space and time,exploiting areas where mean current speeds werelent energy levels were *** birds also oriented into tidal currents during *** together,this suggests that collision risks are low for cormorants at this site,as the 2 conditions avoided by cormorants(high mean current speeds and turbulence levels)are associated with operational tidal ***-all,we suggest that this modified theodolite system is well-suited to the quantification of movement in small areas associated with particular development strategies,including sustainable energy devices.

关键词： GPS habitat use movement ecology seabird tidal turbine

Sex-specific differences in white matter microvascular integrity after ischaemic stroke

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Stroke & Vascular Neurology 2019年第4期4卷 198-205页

作者： mark R Etherton Ona Wu Pedro Cougo Svetlana lorenzano Hua li lisa Cloonan mark J R J Bouts Arne lauer Ken Arai Eng H lo Steve K Feske Karen l Furie Natalia S Rost Department of Neurology Massachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA Martinos Center for Biomedical Imaging Massachusetts General HospitalCharlestownMAUnited States Department of Radiology Massachusetts General Hospital and Harvard Medical SchoolBostonMAUnited States Medical School of Ribeirao Preto University of Sao PauloSao PauloBrazil Department of Human Neurosciences Sapienza University of RomeRomeItaly Institute of Psychology Leiden UniversityLeidenNetherlands Department of Neuroradiology Goethe-Universitat Frankfurt am MainFrankfurtGermany Department of Neurology Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUnited States Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRhode IslandUSA

background and purpose Functional outcomes after ischaemic stroke are worse in women,despite adjusting for differences in comorbidities and treatment *** matter microvascular integrity represents one risk factor for poor long-term functional outcomes after ischaemic *** aim of the study is to characterise sex-specific differences in microvascular integrity in individuals with acute ischaemic *** A retrospective analysis of subjects with acute ischaemic stroke and brain MRI with diffusion-weighted(DWI)and dynamic-susceptibility contrast-enhanced(DSC)perfusion-weighted imaging obtained within 9 hours of last known well was *** the hemisphere contralateral to the acute infarct,normal-appearing white matter(NAWM)microvascular integrity was measured using the K_(2) coefficient and apparent diffusion coefficient(ADC)*** analyses for predictors of K_(2) coefficient,DWI volume and good outcome(90-day modified Rankin scale(mRS)scorelusion criteria for *** no difference in age,women had increased NAWM K_(2) coefficient(1027.4 vs 692.7×10^(-6)/s;p=0.006).In women,atrial fibrillation(β=583.6;p=0.04)and increasing NAWM ADC(β=4.4;p=0.02)were associated with increased NAWM K_(2) *** multivariable regression analysis,the K_(2) coefficient was an independent predictor of DWI volume in women(β=0.007;p=0.01)but not *** In women with acute ischaemic stroke,increased NAWM K_(2) coefficient is associated with increased infarct volume and chronic white matter structural *** studies investigating sex-specific differences in white matter microvascular integrity are needed.

关键词： microvascular white coefficient

Mitigation of spectral leakage for single carrier, block-processing cognitive radio receivers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital Communications and Networks 2018年第2期4卷 106-110页

作者： Adam C. Polak mark Wagner Marco F. Duarte Robert W. Jackson Dennis l. Goeckel Electrical and Computer Engineering Department University of Massachusetts Amherst United States

Cognitive Radio （CR） is a multiuser, wireless communication concept that allows for a dynamic and adaptive assignment of spectral resources. The coexistence of multiple users, often transmitting at significantly different power levels, makes CR receivers vulnerable to spectral leakage caused by components＇ nonlinearities and timetruncation of the processed signal records. In this work we propose a method for mitigating the latter with an adaptive choice of the length of the processing block size. With simulations we show that a significant leakage reduction that leads to receiver dynamic range improvement of around 10 dB can be achieved with the proposed method.

关键词： Spectral leakage Dynamic range Single carrier block transmission Interference White space Cognitive radio

Direct bandgap germanium-on-silicon inferred from 5.7% <100> uniaxial tensile strain [Invited]

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2014年第3期2卷 S0008-S0013页

作者： David S.Sukhdeo Donguk Nam Ju-Hyung Kang mark l.Brongersma Krishna C.Saraswat Department of Electrical Engineering Stanford UniversityStanfordCalifornia 94305USA Department of Materials Science and Engineering Stanford UniversityStanfordCalifornia 94305USA

We report uniaxial tensile strains up to 5.7%along h100i in suspended germanium(Ge)wires on a silicon substrate,measured using Raman *** strain is sufficient to make Ge a direct bandgap *** calculations show that a significant fraction of electrons remain in the indirect conduction valley despite the direct bandgap due to the much larger density of states;however,recombination can nevertheless be dominated by radiative direct bandgap transitions if defects are *** then calculate the theoretical efficiency of direct bandgap Ge lEDs and *** strained Ge wires represent a direct bandgap Group IV semiconductor integrated directly on a silicon platform.

关键词： spectroscopy. strain bandgap