检索结果-南通市图书馆

Nanomanufacturing and Metrology 2022年第1期5卷 60-66页

作者： nathan black David Edwards Niall Browne Joseph G.M.Guy Niyorjyoti Sharma Kristina M・Holsgrove Aaron B.Naden Raymond G.P.McQuaid Brian J.Rodriguez Amit Kumar School of Maths and Physics Queen's University BelfastBelfast BT7 INNUK School of Chemistry University of St.AndrewsSt Andrews KY169STUK School of Physics University College DublinBelfieldDublin 4Ireland

The realization of a mixed-phase microstructure in strained BiFeO_(3)(BFO)thin films has led to numerous novel effects derived from the coexistence of the tetragonal-like monoclinic phase(T phase)and rhombohedral-like monoclinic phase(R phase).Strong strain and polarization diiferences between the phases should result in a high level of transformation plasticity,which enables the continuous alteration of the relative proportion of R and T states in response to external forces.Although the potential for utilizing such plasticity to control mixed-phase populations under external stimuli is evident,direct experi・mental evidence backed by equilibrium predictions has not yet been fully demonstrated.Here we demonstrate deterministic control of mixed-phase populations in an epitaxially strained BFO thin film through the application of localized stresses and electric fields in a reversible manne匚The results illustrate and rationalize deterministic control of mixed phases in strained BFO films,which could be crucial in tuning their functional properties.The findings also highlight a new multiparametric technique in the scanning probe lithography toolbox based on tip-assisted electric and strain field manipulation of functional properties that might find application beyond the ferroelectric domain and structural phase lithography.

关键词： Phase competition Ferroelectric Stress Lithography

Chiral Recognition of Dansyl Derivatives with an Amino Acid-Based Molecular Micelle: A Molecular Dynamics Investigation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Physical Chemistry 2021年第2期11卷 64-86页

作者： Mauro Garcia nathan black Eugene Billiot Fereshteh Billiot Kevin F. Morris Yayin Fang Department of Physical and Environmental Sciences Texas A&M University-Corpus Christi Corpus Christi TX USA Department of Chemistry Carthage College Kenosha WI USA Department of Biochemistry and Molecular Biology Howard University Washington DC USA

In this study, the chiral separation mechanisms of Dansyl amino acids, including Dansyl-Leucine (Dans-Leu), Dansyl-Norleucine (Dans-Nor), Dansyl-Tryptophan (Dans-Trp) and Dansyl-Phenylalanine (Dans-Phe) binding to poly-sodium N-undecanoyl-(L)-Leucylvalinate, poly (SULV), were investigated using molecular dynamics simulations. Micellar electrokinetic chromatography (MEKC) has previously shown that when separating the enantiomers of these aforementioned Dansyl amino acids, the L-enantiomers bind stronger to poly (SULV) than the D-enantiomers. This study aims to investigate the molecular interactions that govern chiral recognition in these systems using computational methods. This study reveals that the computationally-calculated binding free energy values for Dansyl enantiomers binding to poly (SULV) are in agreement with the enantiomeric order produced in experimental MEKC studies. The L-enantiomers of Dans-Leu, Dans-Nor, Dans-Trp, and Dans-Phe binding to their preferred binding pockets in poly (SULV) yielded binding free energy values of -21.8938, -22.1763, -21.3329 and -13.3349 kJ·mol-1, respectively. The D-enantiomers of Dans-Leu, Dans-Nor, Dans

关键词： Amino Acid Based Molecular Micelles Molecular Modeling Computational Chemistry Chiral Recognition

Effects of pyrethroid and organophosphate insecticides on reared black soldier fly larvae(Hermetia illucens)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2024年第3期31卷 817-834页

作者： nathan Meijer Lisa Zoet Theo de Rijk Paul Zomer Deborah Rjkers H.J.van der Fels-Klerx Joop J.A.van Loon Wageningen Food Safety Research(WFSR) Part of Wageningen University and ResearchWageningenThe Netherlands Bestico B.V. Industrieweg 6Berkel en RodenrjsThe Netherlands Plant Sciences Group Laboratory of EntomologyWageningen UniversityWageningenTheNetherlands

black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed source.These insects may be exposed to insecticide residues in the rearing substrate.This study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'performance.The toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were determined.The addition of PBO to cypermethrin enhanced its relative potency with a factor 2.6.These data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in yield.Exposure to multiple substances at lower concentrations resulted in negative additive and synergistic effects.Of the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/kg.Analytical results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of PBO.Transfer of organophosphates was overall low(<2%),but ranged from 8%to 75%for pyrethroids.Due to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in noncompliance.It is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.

关键词： feed insects pesticides rearing substrate

Systematic Radio Telescope Alignment Using Portable Fringe Projection Profilometry

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nanomanufacturing and Metrology 2024年第1期7卷 75-85页

作者： Joel Berkson Justin Hyatt nathan Julicher Byeongjoon Jeong Isaac Pimienta Rachel Ball Wyatt Ellis Jason Voris Diego Torres‑Barajas Daewook Kim James C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event horizon.Astronomers are now aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental laws of gravity that govern our universe.To achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger quantities.Projects like the next-generation Very Large Array(ngVLA)and the Square-Kilometer Array(SKA)require building hundreds of telescopes with diameters greater than 10 ms over the next decade.This has a twofold effect.Radio telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large quantities.Both of these problems can be solved with improved methods for surface metrology that are faster and more accurate with a higher resolution.This leads to faster and more accurate panel alignment and,therefore,a more productive observatory.In this paper,we present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning two panels on a 3-m radio telescope dish.The measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： Metrology Fringe projection profilometry Off-axis alignment Radio astronomy Radio antenna

Association between NNAL and Mortality in U.S. Adults, NHANES 2007-2014 with 2015 Mortality Follow-Up

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Preventive Medicine 2023年第8期13卷 239-255页

作者： nathan M. Holt Ryan A. black Qiwei Liang Saul Shiffman Regulatory Science Juul Labs Inc. Washington DC USA Pinney Associates Inc. Pittsburgh USA

Cigarette smoking is a leading cause of premature mortality, attributable to chronic exposure to toxic compounds in cigarette smoke, including tobacco-specific nitrosamines, which are known carcinogens. This research aims to assess the association between NNAL, a metabolite of the tobacco-specific nitrosamine NNK, and mortality. Data from 14,766 U.S. adults aged 21 - 79 in the National Health and Nutrition Examination Survey (2007-2014) included smoking status and urinary NNAL concentration at the time of examination. These data were linked to participants’ subsequent mortality status as recorded in the public-use Linked Mortality File (through 2015). Cox proportional hazards regression models assessed the relative risk of all-cause, cancer, cardiovascular disease (CVD), and other-causes mortality for increasing levels of natural log (creatinine-adjusted NNAL). In the whole sample, a unit increase in log (NNAL) is associated with a 20% higher risk of all-cause (HR = 1.20;95% CI: 1.16 - 1.24), cancer (HR = 1.20;95% CI: 1.14 - 1.26), CVD (HR = 1.21;95% CI: 1.12 - 1.31) and other-causes (HR = 1.20;95% CI: 1.15 - 1.25) mortality. Among current smokers, a unit increase in log (NNAL) is associated with 44% higher cancer mortality risk (HR = 1.44;95% CI: 1.08 - 1.92) and a 96% higher CVD mortality risk (HR = 1.96;95% CI: 1.20 - 3.20). Risks of all-cause and other-causes mortality, but neither cancer nor CVD mortality, were positively associated with NNAL among never and former smokers. Inferences are limited by the observational nature of the data, and by the focus on a single biomarker of tobacco-related exposure. The findings suggest that urinary NNAL concentration is acting as a proxy for exposure to the toxicants in cigarette smoke rather than as a biomarker of disease-specific mortality risk.

关键词： NHANES NNAL Mortality Smoking Cigarettes

Association of COVID- 19 with respiratory syncytial virus (RSV) infections in children aged 0-5 years in the USA in 2022: a multicentre retrospective cohort study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Family Medicine and Community Health 2023年第4期11卷 45-55页

作者： Lindsey Wang Pamela B Davis nathan Berger David C Kaelber Nora Volkow Rong Xu Center for Science Healthand SocietyCase Western Reserve UniversityClevelandOhioUSA Center for Community Health Integration Case Western Reserve University School of MedicineClevelandOhioUSA The Center for Clinical Informatics Research and Education and the Departments ofInternal Medicine Pediatricsand Population and Quantitative Health SciencesMetroHealth Medical CenterClevelandOhioUSA National Institute on Drug Abuse National Institute of HealthBethesdaMarylandUSA Center for AI in Drug Discovery Case Western Reserve University School of MedicineClevelandOhioUSA

Objective To investigate whether COVID-19 infection was associated with increased risk for incident respiratory syncytial virus(RSV)infections and associated diseases among young children that might have contributed to the 2022 surge of severe paediatric RSV cases in the USA.Design This is a retrospective population-based cohort study.Five outcomes were examined,including overall RSV infection,positive lab test-confirmed RSV infection,clinically diagnosed RSV diseases,RSV-associated bronchiolitis and unspecified bronchiolitis.Risk ratio(RR)and 95%CI of the outcomes that occurred during the 2022 and 2021 RSV seasons were calculated by comparing propensity-score matched cohorts.Setting Nationwide multicentre database of electronic health records(EHRs)of 61.4million patients in the USA including 1.7million children 0–5 years of age,which was accessed through TriNetX Analytics that provides web-based and secure access to patient EHR data from hospitals,primary care and specialty treatment providers.Participants The study population consisted of 228940 children of 0–5 years with no prior RSV infection who had medical encounters in October 2022.Findings were replicated in a separate study population of 370919 children of 0–5 years with no prior RSV infection who had medical encounters in July 2021–August 2021 during a non-overlapping time period.Results For the 2022 study population(average age 2.4 years,46.8%girls,61%white,16%black),the risk for incident RSV infection during October 2022–December 2022 was 6.40%for children with prior COVID-19 infection,higher than 4.30%for the matched children without COVID-19(RR 1.40,95%CI 1.27 to 1.55);and among children aged 0–1year,the overall risk was 7.90%for those with prior COVID-19 infection,higher than 5.64%for matched children without(RR 1.40,95%CI 1.21 to 1.62).For the 2021 study population(average age 2.2 years,46%girls,57%white,20%black),the risk for incident RSV infection during July 2021–December 2021 was 4.85%for children with prior COVID-19 infection,higher than 3.68

关键词： infections matched centre

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

华尔街史上最挣钱的单笔投资

中国证券期货 2014年第8期17卷 56-60页

作者： nathan Vardi

去年11月，由亿万富豪莱昂·布莱克（Leon black）、马克·罗文（Marc Rowan）以及约书亚·哈里斯（Joshua Harris）掌控的强大并购投资机构——阿波罗全球管理公司（Apollo Global Management）完成了一项投资的退出。这项投资可以说... 详细信息

去年11月，由亿万富豪莱昂·布莱克（Leon black）、马克·罗文（Marc Rowan）以及约书亚·哈里斯（Joshua Harris）掌控的强大并购投资机构——阿波罗全球管理公司（Apollo Global Management）完成了一项投资的退出。这项投资可以说是有史以来最赚钱的私募股权投资交易。

关键词：投资机构华尔街挣钱私募股权投资亿万富豪管理公司布莱克哈里斯

Color of Vertically-Suspended Structure Does Not Impact the Growth of Rainbow Trout Reared in Circular Tanks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Animal Sciences 2020年第4期10卷 706-713页

作者： Edgar Meza Misty D. Jones nathan Huysman Jill M. Voorhees Michael E. Barnes Department of Game Fish and Parks McNenny State Fish Hatchery Spearfish South Dakota USA

This study examined the effects of five different colors of vertically-suspended environmental enrichment on the growth of juvenile Shasta strain rainbow trout (Oncorhynchus mykiss) during hatchery rearing in circular tanks. The colors used were silver (unpainted aluminum—control), safety red, semi-gloss black, hunter green, and safety blue. After 86 days, total tank weight, weight gain, and feed conversion ration were not significantly different among any of the color treatments. Individual fish weights, lengths, and condition factors were also not significantly different among the treatments. The results of this study indicate that the relatively small amount of color present on the suspended structure did not affect rainbow trout growth. Thus, the inherent silver color of the aluminum angles does not need to be changed.

关键词： Environmental Enrichment Oncorhynchus mykiss Salmonids Color

Population Status and Trend of the Maasai Ostrich in the Mid Kenya—Tanzania Borderland

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Natural Resources 2016年第10期7卷 558-579页

作者： Moses Makonjio Okello John Warui Kiringe Lekishon Kenana Fiesta Warinwa Hanori Maliti Noah Wasilwa Sitati Erastus Kanga Samwel Bakari Stephen Ndambuki Philip Muruthi nathan Gichohi Edeus Massawe David Kimutai Machoke Mwita Daniel Muteti SFS Center for Wildlife Management Nairobi Kenya Moi University Department of Tourism Eldoret Kenya Kenya Wildlife Service Nairobi Kenya African Wildlife Foundation Nairobi Kenya Tanzania Wildlife Research Institute Arusha Tanzania

The Maasai ostrich (Struthio camelus) is a the largest avian species in East Africa and though it’s not considered to be a species of conservation concern, some populations are on the decline and this is attributed to bush meat activities, predation on their eggs illegal consumption by humans, habitat destruction and forage competition with other large wildlife species. Climate change is also emerging to be another major threat due to interference with food availability which in turn interferes with the breeding rhythm. Thus, this study examined the population status, trend and distribution of the Maasai ostrich in the Southern Kenya and Northern Tanzania borderland after the 2007 to 2009 drought. The results showed that the species was found across the entire borderland but the Amboseli region had the highest number and density of Maasai ostrich (726.00 ± 100.9;0.08 ± 0.01 ostriches per km2), followed by Lake Natron area (330.8 ± 69.8;0.05 ± 0.01 ostriches per km2) and the least was in West Kilimanjaro (85.5 ± 18.0;0.03 ± 0.01 ostriches per km2). Drought caused a decline in the population of the Maasai ostrich but the Amboseli area experienced the highest decline in density (?13.44 ± 12.61) compared to other borderland sectors. However, the populations increased in most sectors after the drought, and wet season numbers and densities were higher than the dry season. The highest positive increase in number and density was in Lake Natron area (+85.65 ± 91.06) followed by West Kilimanjaro (+68.39 ± 59.54), and the least was in the Magadi area (+22.26 ± 32.05). There is a need to enhance conservation of avian species like the Maasai ostrich other than just focusing on the charismatic species such as the African elephant and black rhino. We therefore recommend joint collaboration in monitoring all large wildlife populations across the Kenya-Tanzania borderland with a view of understanding their status, trend and best management actions that can enhance their conservation.

关键词： Borderland Kenya Maasai Ostrich Population Trend and Status Tanzania

Optical Detection of Distal Lung Enzyme Activity in Human Inflammatory Lung Disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biomedical Engineering Frontiers 2021年第1期2卷 44-54页

作者： Alicia Megia-Fernandez Adam Marshall Ahsan R.Akram Bethany Mills Sunay V.Chankeshwara Emma Scholefield Amy Miele Bruce C.McGorum Chesney Michaels nathan Knighton Tom Vercauteren Francois Lacombe Veronique Dentan Annya M.Bruce Joanne Mair Robert Hitchcock Nik Hirani Chris Haslett Mark Bradley Kevin Dhaliwal EaStCHEM The University of Edinburgh School of ChemistryJoseph Black BuildingWest Mains RoadEdinburghUK EH93FJ Translational Healthcare Technologies Group Centre for Inflammation ResearchQueen’s Medical Research InstituteUniversity of Edinburgh47 Little France CrescentEdinburgh BioQuarterEdinburghUK EH164TJ The Roslin Institute and Royal(Dick)School of Veterinary Studies University of EdinburghEaster BushMidlothianUK EH259RG Department of Biomedical Engineering University of Utah36 S Wasatch DrSalt Lake CityUT 84112USA School of Biomedical Engineering&Imaging Sciences King’s College LondonLondonUK SE17EH Mauna Kea Technologies 9Rue d’EnghienParisFrance 75010

Objective and Impact Statement.There is a need to develop platforms delineating inflammatory biology of the distal human lung.We describe a platform technology approach to detect in situ enzyme activity and observe drug inhibition in the distal human lung using a combination of matrix metalloproteinase(MMP)optical reporters,fibered confocal fluorescence microscopy(FCFM),and a bespoke delivery device.Introduction.The development of new therapeutic agents is hindered by the lack of in vivo in situ experimental methodologies that can rapidly evaluate the biological activity or drug-target engagement in patients.Methods.We optimised a novel highly quenched optical molecular reporter of enzyme activity(FIB One)and developed a translational pathway for in-human assessment.Results.We demonstrate the specificity for matrix metalloproteases(MMPs)2,9,and 13 and probe dequenching within physiological levels of MMPs and feasibility of imaging within whole lung models in preclinical settings.Subsequently,in a first-in-human exploratory experimental medicine study of patients with fibroproliferative lung disease,we demonstrate,through FCFM,the MMP activity in the alveolar space measured through FIB One fluorescence increase(with pharmacological inhibition).Conclusion.This translational in situ approach enables a new methodology to demonstrate active drug target effects of the distal lung and consequently may inform therapeutic drug development pathways.

关键词： Lung lung specificity