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Evolution of Anion Relay Chemistry（ARC）: The Design, Synthesis and Validation of New ARC Paradigms with Applications in Complex Molecule Synthesis

化学使世界更美好——中国化学会第七届有机化学学术会议

作者： amos b.smith ⅲ Department of Chemistry Penn Center for Molecular Discovery and the Monell Chemical Senses CenterUniversity of PennsylvaniaPhiladelphiaPA19123

Anion Relay Chemistry(ARC),an effective multi-component union protocol,recently developed and employed in our laboratory,holds great potential for chemists requiring rapid increase of molecular complexity in a single operation,with precise control of stereogenicity on route to both natural and "natural product-like" targets for biomedical research. Employing this technique,a large number of diverse structures can be assembled rapidly from a small number of initiating nucleophiles,bifunctional linchpins,and electrophiles in a controlled,multi-component coupling *** to expand the scope of this tactic include the construction of natural products, as well as libraries of "natural product-like" compounds, which highlight the robust nature of this *** of the ARC tactic,involving both TypeⅠand TypeⅡprotocols,will be presented with illustrations arising from alkaloid and polyketide/macrolide total synthetic ventures currently ongoing in our *** addition,observations regarding the intersection of the ARC TypeⅡprotocol with previously reported reaction pathways, notably in the area of Pd-mediated Takeda and Hiyama/Denmark cross-coupling reactions,will be presented.

关键词： Anion Relay Chemistry Natural Product Synthesis Diversity-Oriented Synthesis brook Rearrangement Cross-Coupling

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Evolution of Anion Relay Chemistry（ARC）: The Design, Synth...

Vitamin A regulates intramuscular adipose tissue and muscle development:promoting high-quality beef production

中国化学会第十一届全国天然有机化学学术会议

作者： amos b.smith,Ⅲ University of Pennsylvania Department of Chemistry

＜正＞Anion Relay Chemistry（ARC）,a robust multi-component synthetic tactic,permits the rapid construction of complex natural and"natural-like"molecules for biomedical *** exploiting various anion（i.e.,charge）relocation tactics via[1,n]-brook rearrangements,the controlled,sequential assembly of architecturally diverse structures can be achieved by virtue of the latent nucleophilicity of the designed bifunctional ARC linchpins,

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Journal of Animal Science and biotechnology 2021年第3期12卷 1138-1147页

作者： Dong Qiao Peng Stephen b.smith Hong Gu Lee Department of Animal Science and Technology Sanghuh College of Life SciencesKonkuk UniversitySeoul 05029South Korea Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA

During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).based on the results of previous studies,other adipose tissue depots(e.g.,perirenal and subcutaneous)develop from the fetal stage primarily as brown adipose *** hyperplastic stage of intramuscular adipose is considered to develop from late pregnancy,but there is no evidence indicating that intramuscular adipose tissue develops initially as brown adipose *** growth of intramuscular adipose continues well into postweaning and is dependent on the timing of the transition to grain-based diets;thereafter,the late-stage development of intramuscular adipose tissue is dominated by *** muscle development,hyperplasia of myoblasts lasts from early(following development of somites in the embryo)to middle pregnancy,after which growth of muscle is the result of hypertrophy of *** A is a fat-soluble compound that is required for the normal immunologic function,vision,cellular proliferation,and *** we review the roles of vitamin A in intramuscular adipose tissue and muscle development in *** A regulates both hyperplasia and hypertrophy in in vitro *** A supplementation at the early stage and restriction at fattening stage generate opposite effects in the beef *** vitamin A supplementation and restriction strategy increase intramuscular adipose tissue development(i.e.,marbling or intramuscular fat)in some in vivo ***,hyperplasia and hypertrophy of myoblasts/myotubes were affected by vitamin A treatment in in vitro ***,some studies reported an interaction between the alcohol dehydrogenase-1C(ADH1C)genotype and vitamin A feed restriction for the development of marbling and/or intramuscular adipose tissue,which was dependent on the timing and level of vitamin A

关键词： Adipose tissue Cattle Intramuscular adipose tissue Muscle development Vitamin A

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David b.smith Steven M.smith John D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

The IUGS/IAGC Task Group on Global Geochemical baselines

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地学前缘 2012年第3期19卷 1-6页

作者： David b.smith Shaun Reeder Alecos Demetriades U.S.Geological Survey DenverCO 80225 USA Institute of Geopkysical and Geochemical Exploration Langfang Hebei 065000 China british Geological Survey KeyworthNottinghamUK Institute of Geology and Mineral Exploration Athens Greece

The Task Group on Global Geochemical baselines,operating under the auspices of both the International Union of Geological Sciences(IUGS) and the International Association of Geochemistry(IAGC),has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth's surface or near-surface *** database and accompanying element distribution maps represent a geochemical baseline against which future human-induced or natural changes to the chemistry of the land surface may be recognized and *** order to accomplish this long-term goal,the activities of the Task Group include:(1) developing partnerships with countries conducting broad-scale geochemical mapping studies;(2) providing consultation and training in the form of workshops and short courses;(3) organizing periodic international symposia to foster communication among the geochemical mapping community;(4) developing criteria for certifying those projects whose data are acceptable in a global geochemical database;(5) acting as a repository for data collected by those projects meeting the criteria for standardization;(6) preparing complete metadata for the certified projects;and(7) preparing,ultimately,a global geochemical *** paper summarizes the history and accomplishments of the Task Group since its first predecessor project was established in 1988.

关键词：国际地质科学联合会伴生元素化学元素地表环境

Vitamin A supplementation downregulates ADH1C and ALDH1A1 mRNA expression in weaned beef calves

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Animal Nutrition 2022年第3期10卷 372-381页

作者： Xue Cheng Jin Dong Qiao Peng Seong Jin Kim Na Yeon Kim Jalil Ghassemi Nejad Danil Kim Stephen b.smith Hong Gu Lee Department of Animal Science and Technology Sanghvi College of Life SciencesKonkuk UniversitySeoul 05029Republic of Korea Asia Pacific Ruminant Institute Icheon 17385Republic of Korea Farm Animal Clinical Training and Research Center Institute of Green-Bio Science and TechnologySeoul National UniversityPyeongchang 25354Republic of Korea Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA

Our previous studies demonstrated that oral vitamin A supplementation during late-stage pregnancy and the neonatal stage enhances birth weight,growth performance,and mRNA expression related to muscle and preadipocyte development in beef *** alcohol dehydrogenase 1C(ADH1C)c.-64T>C genotype also correlated with vitamin A concentration in beef *** study aimed to investigate the effects of vitamin A supplementation on the muscle development and vitamin A metabolism in weaned beef calves with different ADH1C *** male calves(90 d of age;initial bW:89.03 kg[SD 8.60])were stratified according to ADH1C genotype and vitamin A treatment(duration:3 months)and randomly assigned to 4 groups with a 22 factorial *** A treatments included the following:control(10,000 IU/kg of as-fed,*** type;*** type);treatment(40,000 IU/kg of as-fed,*** type;and *** type).Parameters including bW,FI,blood,longissimus dorsi muscle,and liver status during the experimental period were analyzed using the generalized linear model(GLM)procedure and Tukey's test by SAS 9.4 *** vitamin A was significantly increased(PbW,ADG and FI showed no differences between the *** addition,mRNA expression in longissimus dorsi muscle revealed upregulation of paired box 7(PAX7)(Pbased on biopsy *** ADH1C and aldehyde dehydrogenase(ALDH)1A1 mRNA expression was downregulated(Pby vitamin A *** TC type of ADH1C showed higher mRNA expression than the TT ***,no effect was observed on adipogenic mRNA expression(preadipocyte factor-1[PREF-1],peroxisome proliferator-activated rece

关键词： Vitamin A ADH1C genotype Muscle development Korean native calves

Rapid, simple, low-cost smartphone-based fluorescence detection of Escherichia coli

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International Journal of Agricultural and biological Engineering 2021年第3期14卷 189-193页

作者： Dante Rojas-barboza Edward Park Rolfe Sassenfeld Jeremy Winder Geoffrey b.smith Delia Valles-Rosalles Efren Delgado Young Ho Park Family and Consumer Science Department New Mexico State UniversityLas CrucesNM 883003USA biology Department University of PennsylvaniaPhiladelphiaPA 19104USA Electronics&Computer Engineering Technology New Mexico State UniversityLas CrucesNM 88003USA biology Department New Mexico State UniversityLas CrucesNM 88003USA Industrial Engineering Department New Mexico State UniversityLas CrucesNM 88003USA Mechanical Engineering Department New Mexico State UniversityLas CrucesNM 88003USA

Food and waterborne diseases pose considerable public health threats even in highly industrialized parts of the *** of these pathogens in food can be Escherichia coli O157:H7,Salmonella sp.,and Listeria ***,reliable detection of pathogens mitigates serious health problems and economic losses due to outbreaks and robust tests safeguard the food *** this study,a smartphone-based apparatus was employed to demonstrate quantitative detection of *** validate the applicability of the present smartphone-based fluorescence device,RNA was extracted from the *** K-12 strain and amplified using two different primers(dnaK and rpoA)via quantitative polymerase chain reaction(qPCR).Serial dilutions of RNA from 10 to 0.0001 ng/μL were prepared at the start of the PCR amplification and the PCR products were detected by CYbR Green1-based *** a proof-of-concept test for the smartphone system,samples from these PCR products were then *** detection system employed a novel algorithm to analyze fluorescence signals and read changes in *** DNA *** correlations between the fluorescence percentage and DNA concentrations were R=0.945 for the dnaK primer and R=0.893 for the rpoA primer,*** this new fluorescent analysis technique resulted in comparable accuracy to the real-time PCR fluorescent signal *** key innovation of this approach was to combine efficient image processing encoded into a smartphone application with a low-cost 3-D printed device that allowed quantification of bacterial nucleic acid.

关键词： smartphone fluorescence E.coli low-cost 3D-print

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身无双翼亦能飞

疯狂英语（初中天地） 2007年第4期 18-19页

作者： Elizabeth b.smith 菜菜

以下是一位13岁美国小女孩的骑马经历,看完之后,大家是不是也跃跃欲试呢?这个春天,让我们随她一起,策马扬鞭踏青去!

关键词：经过马鞍

Dietary substitution of soybean oil with coconut oil in the absence of dietary antibiotics supports growth performance and immune function in nursery and grower pigs

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Journal of Animal Science and biotechnology 2020年第2期11卷 480-492页

作者： Andrea G.braundmeier-Fleming Cassandra S.Skenandore Lesly Gil Victoria Jacobsen Melissa Cregger Taylor badger Mallory Karr Guoyao Wu Stephen b.smith Annie E.Newell-Fugate Department of Medical Microbiology Immunology and Cell BiologySchool of MedicineSouthern Illinois UniversitySpringfieldIL 62702USA Department of Veterinary Physiology and Pharmacology College of Veterinary Medicine and Biomedical SciencesTexas A&M University4466 TAMUCollege StationTX 77843USA Department of Animal Science Texas A&M University2471 TAMUCollege StationTX 77843USA

background:We hypothesized that supplementation of nursery and grower pig diets with coconut oil in the absence of antibiotics would yield maintenance of glucose homeostasis,growth performance,and immune function similar to what is achieved with nursery and grower pig diets containing *** received the same base treatment diets from d24(weaning)to d71 of age and had blood and fecal samples collected on d24,d31,d45 and d71 for measurement of whole blood glucose,serum insulin,cortisol and cytokines,and fecal *** had weekly weights and daily feed consumption measured throughout the *** were euthanized at d71 and subcutaneous fat and ileal contents were collected for assessment for fatty acids and microbiome,*** treatments consisted of 2%soybean oil plus antibiotics(AbX;n=22),2%soybean oil without antibiotics(NAbX;n=22),and 2%coconut oil without antibiotics(COC;n=22).Statistical analysis examined the effect of diet within each timepoint using a repeated measures ***:Pigs fed COC diet had decreased serum insulin levels,maintained feed intake,feed conversion and weight gain,and,based on serum cytokines and fecal microbiome,were immunologically similar to AbX-fed ***,NAbX-fed pigs performed similarly to the AbX-fed pigs in all parameters except for serum ***,there was no difference in the incidence of diarrhea between any of the diet ***:This study demonstrates that dietary antibiotics are not necessary to maintain growth performance in nursery and grower ***,dietary antibiotics appear to modulate circulating cytokine *** coconut oil is neither harmful nor helpful to growth performance or immune function in nursery and grower pigs but does modulate serum insulin ***,while coconut oil fed at 2%by weight is a suitable substitute for dietary antibiotics,this study suggests that no substitute for dietary antibiotics is needed at all.

关键词： Alternatives Antibiotic supplementation Grower pigs Medium chain fatty acids Nursery pigs Oil

History and Progress of the North American Soil Geochemical Landscapes Project,2001-2010

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地学前缘 2012年第3期19卷 19-32页

作者： David b.smith William F.Cannon Laurel G.Woodruff Francisco Moreira Rivera Andrew N.Rencz Robert G.Garrett US Geological Survey MS 973 Denver CO 80225 USA US Geological Survey MS 9541 Reston VA 20192 USA US Geological Survey 2280 Woodale Drive St. Paul MN 55112 USA Servicio Geologico Mexicano 78280 San Luis Potosl S. L. P. Mexrico Geological Survey of Canada Natural Resources Canada 601 Booth St. Ottawa ON Canada K IA OE8

In 2007,the *** Survey,the Geological Survey of Canada,and the Mexican Geological Survey initiated a low-density(1 site per 1600 km2,13323 sites) geochemical and mineralogical survey of North American soils(North American Soil Geochemical Landscapes Project).Sampling and analytical protocols were developed at a series of workshops in 2003-2004 and pilot studies were conducted from *** ideal sampling protocol at each site includes a sample from 0-5 cm depth,a composite of the soil A horizon,and a sample from the soil C *** ba,be,bi,Cd,Ce,Co,Cr,Cs,Cu,Ga,In,La,Li,Mn,Mo,Nb,Ni,P,Pb,Rb,Sb,Sc,Sn,Sr,Te,Th,Tl,U,V,W,Y,and Zn by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry following a near-total digestion in a mixture of HCl,HNO3,HClO4,and *** methods are used for As,Hg,Se,and total C on this same size *** major mineralogical components are determined by a quantitative X-ray diffraction *** in the conterminous *** completed in 2010(c.4800 sites) with chemical and mineralogical analysis currently *** Mexico,approximately 66% of the sampling(871 sites) had been done by the end of 2010 with completion expected in *** completing sampling in the Maritime provinces and portions of other provinces(472 sites,7.6% of the total),Canada withdrew from the project in *** results for a swath from the central *** Florida clearly show the effects of soil parent material and climate on the chemical and mineralogical composition of soils.A sample archive will be established and made available for future investigations.

关键词：墨西哥地质学电感耦合等离子体