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CCS Chemistry 2024年第4期6卷 1060-1070页

作者： Sifan Li Hai-wu Du Paul w.Davies wei Shu Department of Chemistry Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhen 518055Guangdong School of Chemistry University of BirminghamEdgbastonBirmingham B152TT

Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to ***,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been *** use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial *** strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group *** synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted *** investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.

关键词： photocatalysis α-tertiary primary amines 1 2-amino alcohols vinyl azide electron donor-acceptor complex

Prevalence and intensity of urinary schistosomiasis and soil-transmitted helminths among women of reproductive age in Mwaluphamba,Kwale

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Asian Pacific Journal of Tropical Medicine 2024年第2期17卷 71-83页

作者： Samuel M.Ngui Joseph M.Mwangangi Joachim Richter Josephine w.Ngunjiri Department of Biological Sciences University of EmbuKenya Medical Entomology Kenya Medical Research Institute(KEMRI)Center for Geographic Medicine Research Coast KilifiKenya Institute of International Health Global Health CenterCharitéUniversity MedicineBerlinCorporate Member of Free University and Humboldt University and Berlin Institute of HealthBerlinGermany Swiss Tropical and Public Health Institute BaselSwitzerland Tropical and Infectious Diseases Department of Biological sciencesUniversity of EmbuKenya

Objective:To assess the epidemiology of urinary schistosomiasis and soil-transmitted helminthiasis among women of reproductive age in Mwaluphamba,Kwale County,***:A community-based cross-sectional study design was employed to randomly sample 422 women of reproductive age(15-waluphamba *** specimens were collected and examined using the Kato-Katz method,while filtration technique was used to analyze urine ***’sociodemographic details were obtained using a standardized ***:Urinary schistosomiasis prevalence was at 4.7%(20/422,95%CI 2.8%-6.9%)while the prevalence of soil-transmitted helminthiasis infection was 4.5%(19/422,95%CI 2.6%-6.7%).The infection intensities of urinary schistosomiasis among the study participants ranged from 1 to 120 eggs/10 mL of urine with median egg count of 18.45 eggs/10 *** patients were diagnosed with light infection,of 56.16 egg/gram and 48.48 egg/gram for Trichuris trichiura and hookworms,*** without latrines had 15.7 times higher risk of having urinary schistosomiasis compared to those with a ***,use of surface water(aOR=1.0,95%CI 0.2-1.4,P=0.010)and crossing the river to go to a place(aOR=1.1,95%CI 0.3-1.6,P=0.009)were statistically significant risk factors for getting urinary *** bivariable regression analysis,defecating around the water source(OR=4.3,95%CI 1.5-12.9)had a statistically significant association with the prevalence of soil-transmitted helminthiasis(P=0.008).Conclusions:This study has given an insight on the prevalence and intensity of urinary schistosomiasis and soil-transmitted helminthiasis in Mwaluphamba location that form a basis for strengthening the control and elimination programmes for these neglected tropical diseases.

关键词： Urinary schistosomiasis Prevalence Soiltransmitted helminths Mwaluphamba

A novel method for clustering cellular data to improve classification

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Neural Regeneration Research 2025年第9期20卷 2697-2705页

作者： Diek w.wheeler Giorgio A.Ascoli Center for Neural Informatics Structures&PlasticityKrasnow Institute for Advanced Study Bioengineering Department Volgenau School of Engineering George Mason University FairfaxVAUSA

Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are *** recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within *** we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical *** general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical *** demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons.

关键词： cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering

Determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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Pedosphere 2024年第3期34卷 530-539页

作者： Daniel D.SAURETTE Asim BISwAS Richard J.HECK Adam w.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM *** advances in sampling design,a critical gap remains in determining the number of samples required for DSM *** propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin *** preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample *** technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results showed increasing minimum sample size with an increase in the QR *** sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

Inertial mixing of acoustically levitated droplets for time-lapse protein crystallography

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Droplet 2024年第3期3卷 91-101页

作者： Soichiro Tsujino Yohei Sato Shichao Jia Michal w.Kepa Sofia Trampari Takashi Tomizaki Division of Biology and Chemistry Paul Scherrer InstitutVilligenSwitzerland Swiss Nanoscience Institute University of BaselBaselSwitzerland Division Scientific Computing Theory and DataPaul Scherrer InstitutVilligenSwitzerland Biozentrum University of BaselBaselSwitzerland Photon Science Division Paul Scherrer InstitutVilligenSwitzerland

Varying the chemical consistency of acoustically levitated droplets opens up an in situ study of chemical and biochemical reactions in small ***,the opti-mization of the mixing time and the minimization of the positional instability induced by solution dispensing are necessary for practical applications such as the study of the transient state of macromolecules crystallography during the ligand binding *** this purpose,we study the inertial mixing in a configuration compatible with the room-temperature crystallography using the acoustic levitation diffractometer,therein solution drops ejected at high velocity collide and coalesce with droplets dis-pensed on acoustically levitated and rotating polymer thin-film sample *** the proposed method,we are able to achieve the mixing time of∼0.1 s for sub-micro and a few microliter *** observed short mixing time is ascribed to the rapid penetration of the solution into the droplets and confirmed by a computational fluid dynamic *** demonstrated accelerated solution mixing is tested in a pilot time-lapse protein crystallography experiment using the acoustic levitation *** results indicate the detection of transient ligand binding state within 2 s after the solution dispensing,suggesting the feasibility of the proposed method for studying slow biochemical processes.

关键词： mixing droplets transient

Deletion of Axin1 in aggrecan-expressing cells leads to growth plate cartilage defects in adult mice

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Genes & Diseases 2024年第4期11卷 149-151页

作者： Dan Yi Hongting Jin william w.Lu Chunxiang Zhang Guozhi Xiao Liping Tonag Di Chen Research Center for Computer-aided Drug Discovery Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China PFaculty of Pharmaceutical Sciences Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China The First College of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhouZhejiang 310053China Department of Cardiology Basic Medicine Innovation Centerfor Cardiometabolic Diseases of Ministry of EducationInstitute of Cardiovascular ResearchThe Affiliated HospitalSouthwest Medical UniversityLuzhouSichuan 646000China School of Medicine Southern University of Science and TechnologyShenzhenGuangdong 518055China

In mammals,skeletal bone development begins at hyaline cartilage formation at the early embryonic stage.1Then osteoblasts from the periosteum,which are distributed surrounding the hyaline cartilage,build up compact bone to formdiaphysis and spongy bone known as primary ossification center.1 Next,osteoclasts from the hematopoietic system destroy spongy bone to generate a medullary cavity.

关键词： cartilage skeletal medullary

A parsimonious Bayesian predictive model for forecasting new reported cases of west Nile disease

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Infectious Disease Modelling 2024年第4期9卷 1175-1197页

作者： Saman Hosseini Lee w.Cohnstaedt John M.Humphreys Caterina Scoglio Department of Electrical and Computer Engineering Kansas State UniversityManhattanKSUSA Foreign Arthropod-Borne Animal Diseases Research Unit National Bio-and Agro-defense Facility USDA ARSManhattanKSUSA Foreign Animal Disease Research Unit National Bio-and Agro-defense FacilityUSDA ARSManhattanKSUSA

Upon researching predictive models related towest Nile virus disease,it is discovered that there are numerous parameters and extensive information in most models,thus contributing to unnecessary *** challenge frequently encountered is the lead time,which refers to the period for which predictions are made and often is too *** paper addresses these issues by introducing a parsimonious method based on ICC curves,offering a logistic distribution model derived from the vector-borne SEIR *** existing models relying on diverse environmental data,our approach exclusively utilizes historical and present infected human cases(number of new cases).with a yearlong lead time,the predictions extend throughout the 12 months,gaining precision as new data *** conditions are derived to minimize Bayesian loss,enhancing predictive *** construct a Bayesian forecasting probability density function using carefully selected prior *** these functions,we predict monthspecific infections nationwide,rigorously evaluating accuracy with probabilistic ***,HPD credible intervals at 90%,95%,and 99%levels is *** assessment is conducted for HPD intervals,measuring the proportion of intervals that does not include actual reported cases for 2020e2022.

关键词： west nile virus ICC curve Bayesian model Logistic distribution HPD credible interval

Perturbations in the earthworm metabolite profile during a two-week exposure to metformin

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Emerging Contaminants 2024年第3期10卷 221-229页

作者： J.D.Gillis G.w.Price S.O.Prasher Department of Bioresource Engineering McGill UniversityFaculty of Agricultural and Environmental SciencesMacdonald-Stewart Building MS1-02721111 Lakeshore RoadSainte-Anne-de-BellevueQuebecH9X 3V9Canada Department of Engineering Dalhousie UniversityFaculty of Agriculture39 Cox RoadPO Box 550TruroNova ScotiaB2N 5E3Canada

Metformin is among the most prescribed pharmaceuticals in many countries,and as a result has shown up in biosolids derived from municipal wastewater treatment that are destined for land *** humans taking metformin,the effects include reduced glucose uptake in the intestine,a reduction in gluconeogenesis,increased oxidation of fatty acids,and reduced fatty acid *** effects of metformin on soil-dwelling organisms are not well *** study tested the effects of metformin exposure(0,10,40,160,640μg g^(-1))on the earthworm(***)at four time points(6 h,2 d,7 d,and 14 d)using GC-MS to reveal sub-lethal effects and elucidate potential modes of action for *** were no mortalities observed,and earthworms exposed to the highest concentrations(160 and 640μg g^(-1))gained weight relative to the control on days 7 and *** reductions on day 7 were observed for glucose and malic acid(consistent with a reduction in gluconeogenesis),and for palmitic and margaric acid(consistent with increased oxidation and reduced synthesis of fatty acids).Lactic acid ranked first and second among canonicals 1 and 2 respectively and led to significant differences in discriminant scores across concentration and *** levels increased to equal or greater than the control on day 14,likely caused by reduced exposure as metformin is reported to be readily transformed by microorganisms under aerobic *** observations were consistent with the known effects of metformin in humans,and suggests that a similar mode of action exists in earthworms.

关键词： Metabolites Toxicity Earthworms Metformin GC-MS

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.wang Y.Chen w.B.Yao C.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Three- and Four-Dimensional Generalized Pythagorean Numbers

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Advances in Pure Mathematics 2024年第1期14卷 1-15页

作者： Alfred wünsche Institute of Physics Humboldt University Berlin Germany

The Pythagorean triples (a, b | c) of planar geometry which satisfy the equation a2+b2=c2 with integers (a, b, c) are generalized to 3D-Pythagorean quadruples (a, b, c | d) of spatial geometry which satisfy the equation a2+b2+c2=d2 with integers (a, b, c, d). Rules for a parametrization of the numbers (a, b, c, d) are derived and a list of all possible nonequivalent cases without common divisors up to d2 is established. The 3D-Pythagorean quadruples are then generalized to 4D-Pythagorean quintuples (a, b, c, d | e) which satisfy the equation a2+b2+c2+d2=e2 and a parametrization is derived. Relations to the 4-square identity are discussed which leads also to the N-dimensional case. The initial 3D- and 4D-Pythagorean numbers are explicitly calculated up to d2, respectively, e2.

关键词： Number Theory Pythagorean Triples Tesseract 4-Square Identity Diophantine Equation