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Journal of Environmental Sciences 2011年第6期23卷 1004-1010页

作者： Irene M.C.Lo samuel C.N.Tang Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

Cationic hydrogel with magnetic property was synthesized via radical polymerization and its removal capacity of chromate from contaminated water was found to be 200 mg/*** Fourier transform infrared spectroscopy（FT-IR） study,the mechanism of chromate removal by hydrogel was found to be non-specific adsorption,mainly due to ion exchange,as evidenced by the positively charged functional group,trimethyl ammonium-N＋（CH3）3,in the *** were accordingly determined by testing di？erent oxyanion adsorption onto the *** results of the chromate adsorption experiments illustrated that the amount of chromate adsorbed was nearly equal to that of the chloride released from the hydrogel,which is part of the evidence for ion *** and multi-oxyanion adsorption experiments were also performed,and it was demonstrated that ion removal was species independent,but charge dependent,another characteristic of the ion exchange *** was found that the same Langmuir model can be applied to best fit the findings of single and multi-oxyanion adsorption,which further indicates the mechanism of chromate removal is attributed to ion *** view of the above,the background anions compete for adsorption sites with chromate,evidenced by inhibitive chromate removal in the presence of background electrolytes in the batch studies,further echoing the ion exchange mechanism.

关键词： adsorption magnetic hydrogel mechanism ion exchange oxyanion

Moments of the folded logistic distribution

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Progress in Natural Science:Materials International 2007年第6期17卷 696-697页

作者： Saralees Nadarajah samuel Kotz School of Mathematics University of ManchesterManchester M60 1QDUK Department of Engineering Management and Systems Engineering George Washington UniversityWashingtonDC 20052USA

The recent paper by Cooray et al. introduced the folded logistic distribution. The moments properties given in the paper appear too complicated. In this note, a simple formula is derived in terms of the well known Ler... 详细信息

关键词： folded logistic distribution Lerch function moments.

Distance assessment of detours by jum ping spiders

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Current Zoology 2020年第3期66卷 263-273页

作者： samuel AGUILAR-ARGUELLO Daniel GERHARD Ximena J.NELSON School of Biological Sciences University of CanterburyPrivate Bag 4800Christchurch 8140New Zealand School of Mathem atics and Statistics University of CanterburyPrivate Bag 4800Christchurch 8140New Zealand

To take an indirect route(detour)in order to reach a specific target requires complex cognitive *** more demanding,from the cognitive point of view,is when the goal is only visible at the beginning of the *** spiders from the family Sa lticidae,vision is a key sensory modal-ity mediating navigation and prey *** acute vision allows them to perform complicated detours,possibly as a consequence of the multitude of potential routes in their typically complex 3-dimensional *** used a 4-route choice test,in which routes differed in being either short or long and in the presence or absence of a lure of a prey item,to investigate route assessment in 2 salticid species,Trite planiceps and Marpissa *** both species showed evidence of motivation to follow lured-routes,judging by the number of times they re-oriented toward them while detouring,we found that Trite chose short routes in preference to long routes,but did not prefer the *** contrast,Marpissa exhibited random route choice,although it ori-ented toward lured-routes more often than control routes(lure absent).Our results suggest that decision-making processes about which route to take occurs before embarking on a route,but this is cognitively *** exhibited cognitive limitations in which the lack of visibility of the goal affected ***,the severity of cognitive limitations depended on *** suggest that variability in spatial ability across the Salticidae may be related to the habitat complexity inhabited by each species.

关键词： cognition cognitive limitations decision-making detour behavior Salticidae spatial task

Thermal scanning probe lithography-a review

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Microsystems & Nanoengineering 2020年第1期6卷 1117-1140页

作者： samuel Tobias Howell Anya Grushina Felix Holzner Juergen Brugger Microsystems Laboratory Ecole Polytechnique Federale de Lausanne(EPFL)1015 LausanneSwitzerland Heidelberg Instruments Nano-SwissLitho AG Technoparkstrasse 18005 ZürichSwitzerland

Fundamental aspects and state-of-the-art results of thermal scanning probe lithography(t-SPL)are reviewed here.t-SPL is an emerging direct-write nanolithography method with many unique properties which enable original or improved nano-patterning in application fields ranging from quantum technologies to material *** particular,ultrafast and highly localized thermal processing of surfaces can be achieved through the sharp heated tip in t-SPL to generate high-resolution *** investigate t-SPL as a means of generating three types of material interaction:removal,conversion,and *** of these categories is illustrated with process parameters and application examples,as well as their respective opportunities and *** intention is to provide a knowledge base of t-SPL capabilities and current limitations and to guide nanoengineers to the best-fitting approach of t-SPL for their challenges in nanofabrication or material *** potential applications of nanoscale modifications with thermal probes still wait to be explored,in particular when one can utilize the inherently ultrahigh heating and cooling rates.

关键词： utilize heated limitations

Inorganic arsenic： A non-genotoxic carcinogen

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Journal of Environmental Sciences 2016年第11期28卷 28-37页

作者： samuel M.Cohen Aparajita Chowdhury Lora L.Arnold Department of Pathology and Microbiology University of Nebraska Medical Center Omaha NE 68198-3135 USA.

Inorganic arsenic induces a variety of toxicities including cancer. The mode of action for cancer and non-cancer effects involves the metabolic generation of trivalent arsenicals and their reaction with sulfhydryl groups within critical proteins in various cell types which leads to the biological response. In epithelial cells, the response is cell death with consequent regenerative proliferation. If this continues for a long period of time, it can result in an increased risk of cancer. Arsenicals do not react with DNA. There is evidence for indirect genotoxicity in various in vitro and in vivo systems, but these involve exposures at cytotoxic concentrations and are not the basis for cancer development. The resulting markers of genotoxicity could readily be due to the cytotoxicity rather than an effect on the DNA itself. Evidence for genotoxicity in humans has involved detection of chromosomal aberrations, sister chromatid exchanges in lymphocytes and micronucleus formation in lymphocytes, buccal mucosal cells, and exfoliated urothelial cells in the urine. Numerous difficulties have been identified in the interpretation of such results, including inadequate assessment of exposure to arsenic, measurement of micronuclei, and potential confounding factors such as tobacco exposure, folate deficiency, and others. Overall, the data strongly supports a non-linear dose response for the effects of inorganic arsenic. In various in vitro and in vivo models and in human epidemiology studies there appears to be a threshold for biological responses, including cancer.

关键词： Arsenic Cancer Genotoxicity Cytotoxicity Regeneration Cell proliferation

Neurotrophic fragments as therapeutic alternatives to ameliorate brain aging

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Neural Regeneration Research 2023年第1期18卷 51-56页

作者： Itzel Ortiz Flores samuel Treviño Alfonso Díaz Department of Health Sciences School of MedicineUniversity of the Americas PueblaPueblaMexico Faculty of Chemical Sciences Benemerita Autonomous University of PueblaPueblaMexico

Aging is a global phenomenon and a complex biological process of all living beings that introduces various *** this physiological process,the brain is the most affected organ due to changes in its structural and chemical functions,such as changes in plasticity and decrease in the number,diameter,length,and branching of dendrites and dendritic ***,it presents a great reduction in volume resulting from the contraction of the gray ***,aging can affect not only cognitive functions,including learning and memory,but also the quality of life of older *** a result of the phenomena,various molecules with notable neuroprotective capacity have been proposed,which provide a therapeutic alternative for people under conditions of aging or some neurodegenerative *** is important to indicate that in recent years the use of molecules with neurotrophic activity has shown interesting results when evaluated in in vivo *** review aims to describe the neurotrophic potential of molecules such as resveratrol(3,5,4′-trihydroxystilbene),neurotrophins(brain-derived neurotrophic factor),and neurotrophic-type compounds such as the terminal carboxyl domain of the heavy chain of tetanus toxin,cerebrolysin,neuropeptide-12,and *** of these molecules have been evaluated by our research *** suggest that these molecules exert an important therapeutic potential,restoring brain function in aging conditions or models of neurodegenerative ***,our interest is in describing the current scientific evidence that supports the therapeutic potential of these molecules with active neurotrophic.

关键词： Alzheimer’s disease brain cerebral cortex cognitive function dendritic spines HC-TeTx hippocampus neurodegeneration neuronal survival neurotrophins

Investigating the effects of peptide-based,MOS and protease feed additives on the growth performance and fecal microbial composition of weaned pigs

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Journal of Animal Science and Biotechnology 2022年第5期13卷 1469-1482页

作者： Prakash Poudel Ryan samuel Crystal Levesque Benoit St-Pierre Himalayan Pet Foods MukilteoWashington 98275USA Department of Animal Science South Dakota State UniversityAnimal Science ComplexBox 2170BrookingsSD 57007USA

Background:Digestive disorders in weaning pigs remain a major challenge for swine *** types of commercial feed additives have been developed to promote gut health and development in young pigs,but their effects on resident gut microbial communities remain largely *** aim of this study was to investigate the impact of a peptide-based product(Peptiva)in combination with mannose oligosaccharides(MOS)and an exogenous protease on the performance and fecal microbiome of nursery ***:A total of 1097 weaned pigs were divided into 44 pens(24-26 pigs/pen)with each pen randomly assigned to one of four experimental diets as part of Phase Ⅱ and Phase Ⅲ of a standard nursery phase feeding *** samples collected from representative control and treatment pigs were used to investigate bacterial composition profiles by high throughput sequencing of PCR-generated amplicons targeting the V1-V3 region of the 16S rRNA ***:Higher gain:feed was observed for pigs fed Peptiva and MOS compared to Controls during the period when experimental diets were fed,but the benefits of supplementation were not maintained after pigs were transitioned to a non-supplemented *** candidate bacterial species,identified as Operational Taxonomic Units(OTUs),were found to have significantly different abundances between control samples and treatment samples during the same *** Phase Ⅲ samples,SD_Ssd-00039,predicted to be a strain of Streptococcus alactolyticus based on nucleotide sequence identity,was the most highly represented of these OTUs with an average abundance in pigs fed Peptiva,MOS and protease that was 3.9 times higher than in *** report also presents evidence of microbial succession that occurred during the trial,with 16 of the 32 most abundant OTUs found to vary between Phase Ⅱ and Phase Ⅲ samples for the same dietary ***:Dietary supplementation with a combination of a peptide-based product,MOS,and protease in

关键词： Bacteria Gut Microbiome MOS Peptide Protease Swine Weaning

Dual representation of expectile-based expected shortfall and its properties

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Probability, Uncertainty and Quantitative Risk 2021年第2期6卷 99-116页

作者： Mekonnen Tadese samuel Drapeau School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences&Shanghai Advanced Institute of Finance(CAFR) Shanghai Jiao Tong UniversityShanghai 200030China

An expectile can be considered a generalization of a *** expected shortfall is a quantile-based risk measure,we study its counterpart-the expectile-based expected shortfall-where expectile takes the place of a *** provide its dual representation in terms of a Bochner *** other properties,we show that it is bounded from below in terms of the convex combination of expected shortfalls,and also from above by the smallest law invariant,coherent,and comonotonic risk measures,for which we give the explicit formulation of the corresponding distortion *** a benchmark to the industry standard expected shortfall,we further provide its comparative asymptotic behavior in terms of extreme value *** on these results,we finally explicitly compute the expectile-based expected shortfall for selected classes of distributions.

关键词： Expectile Expected shortfall Tail conditional expectation Dual representation Coherent risk measure

Uncertainty and filtering of hidden Markov models in discrete time

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Probability, Uncertainty and Quantitative Risk 2020年第1期5卷 68-101页

作者： samuel N.Cohen Mathematical Institute University of OxfordWoodstock RoadOxfordUK

We consider the problem of filtering an unseen Markov chain from noisy observations,in the presence of uncertainty regarding the parameters of the processes *** the theory of nonlinear expectations,we describe the uncertainty in terms of a penalty function,which can be propagated forward in time in the place of the *** also investigate a simple control problem in this context.

关键词： Filtering Optimal control Robustness Nonlinear expectation

Marginalization and invasion of architects＇ role on house projects： Institutional intervention inadequacy and super wicked problems

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Frontiers of Architectural Research 2018年第3期7卷 292-303页

作者： samuel Frim pong Ayirebi Dansoh Department of Building Technology Kumasi Technical University P.O.Box UP 41 KNUST Kumasi Ghana Department of Building Technology Kwame Nkrumah University of Science and Technology Private Mail Bag Kumasi Ghana

The design and construction of houses normally require an architect＇s input. However, architects are increasingly being marginalized in these projects, and their roles are constantly being invaded by others. Despite repeated institutional interventions toward remedying this phenomenon, signs are not abating. This article examines the complexity of this phenomenon to explain the inadequacy of institutional interventions to address the problem. This article conceptualizes the phenomenon of marginalization and role invasion as a super wicked problem with six key features. First, the problem has a difficult definition. Second, the solution involves a large structural and economic burden. Third, time is of the essence. Fourth, multiple stakeholders attempting to solve the problem are part of the cause. Fifth, institutional interventions addressing the issue are weak or ill-equipped. Sixth, institutional interventions discount the future irrationally. The implications of this conceptualization for institutional intervention and research are discussed.

关键词： Client-architect relationship Architectural management House projects Super wicked problems Marginalization and role invasion Institutional interventions