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Teichmller space of.negatively curved metrics on complex hyperbolic manif.lds is not contractible

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Science China Mathematics 2017年第4期60卷 569-580页

作者： f.RRELL f. thomas SORCAR Gangotryi Yau Mathematical Sciences Center and Department of.Mathematical Sciences Tsinghua University Beijing 100084 China Department of.Mathematics Ohio State University Columbus OH 43210 USA

We prove that f.r all n = 4k- 2 and k 2 there exists a closed smooth complex hyperbolic manif.ld M with real dimension n having non-trivial π1(T<0(M)). T<0(M) denotes the Teichm¨uller space of.all negatively curved ... 详细信息

We prove that f.r all n = 4k- 2 and k 2 there exists a closed smooth complex hyperbolic manif.ld M with real dimension n having non-trivial π1(Tf.all negatively curved Riemannian metrics on M, which is the topological quotient of.the space of.all negatively curved metrics modulo the space of.self.dif.eomorphisms of.M that are homotopic to the identity.

关键词： space of.Riemannian metrics negative curvature complex hyperbolic space

Origin of.Symmetry Breaking and Conf.nement in Conducting Polymers with Ring Structures

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Communications in Theoretical Physics 2007年第2X期48卷 366-368页

作者： YUAN Yuan thomas f. George SUN Xin Research Center f.r Quantum Manipulation Fudan University Shanghai 200433 China National Lab of.Inf.ared Physics Shanghai 200083 China Of.ice of.the Chancellor and Center f.r Molecular Electronics Departments of Chemistry & Biochemistry and Physics & Astronomy Univ.ersity of Missouri-St. Louis St. Louis Missouri 63121 USA

A model to describe the main f.atures of.conjugated polymers with ring structures, such as polythiophene and polypyrrole, is constructed. It is shown that the origin of.the symmetry breaking and conf.nement of.a solit... 详细信息

关键词： polymer branch hopping symmetry breaking conf.nement

Identif.cation and initial characterization of.the 3＇ end of.gene transcripts encoding putative members of.the pheromone receptor subf.mily in Lepidoptera

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Insect Science 2012年第1期19卷 64-74页

作者： Stephen f. Garczynski Kevin W. Wanner thomas R. Unruh USDA-ARS Yakima Agricultural Research Laboratory Wapato Washington Department of.Plant Sciences and Plant Pathology Montana State University Bozeman Montana USA

Semiochemicals, including pheromones and kairomones, used in pest man- agement programs reduce the need f.r chemical insecticides, and understanding their interactions with their membrane receptors may help make them more ef.ective in the f.eld. Identif.cation of.odorant receptors in the Lepidoptera has mainly been achieved us- ing bioinf.rmatics to search DNA sequences generated by genome or expressed sequence tag （EST） sequencing projects. This study reports a rapid method to identif. members of.the pheromone receptor subf.mily in Lepidoptera. Degenerate oligonucleotide primers were designed against a conserved amino acid sequence in the carboxyl terminus of.known lepidopteran pheromone receptors, and the primers were used in a 3＇ rapid amplif.ca- tion of.complementary DNA （cDNA） ends procedure. Polymerase chain reaction products generated f.om seven dif.erent lepidopteran species were TA cloned and sequenced. The cDNA sequences of.25 transcripts were determined to encode potential members of.the pheromone receptor subf.mily. These cDNAs ranged f.om 238 to 642 bp and encoded 49-54 amino acids of.the carboxyl terminus. Analysis of.the 3＇ untranslated region reveals that most of.the transcripts contain multiple polyadenylation signal sequences, and in the case of.anduca sexta, an alternate polyadenylation signal appears to be used in transcript processing. The 3＇ untranslated region was also usef.l in determining unique receptors en- coded by transcripts having highly similar nucleotide and amino acid sequences. Overall, this technique provides a complementary method of.pheromone receptor identif.cation in EST sequencing projects, or can be used as a stand-alone method in conjunction with 5＇ rapid amplif.cation of.cDNA ends procedures.

关键词： degenerate primer PCR odorant receptor pheromone receptor polyadeny- lation signals 3' untranslated region

Characterization of.three transcripts encoding small heat shock proteins expressed in the codling moth, Cydia pomonella （Lepidoptera： Tortricidae）

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Insect Science 2011年第5期18卷 473-483页

作者： Stephen f. Garczynski thomas R. Unruh Christelle Guedot Lisa G. Neven USDA-ARS Yakima Agricultural Research Laboratory Wapato Washington USA

Codling moth is a major pest of.apples and pears worldwide. Increasing knowledge of.how this insect responds to environmental stress will improve f.eld and postharvest control measures used against it. The small heat shock proteins （sHsps） play a maj or role in cellular responses to environmental stressors. A degenerate oligonucleotide primer, designed against the conserved α-crystallin domain, was used in 3＇ rapid amplif.cation of.complementary DNA （cDNA） ends reactions to amplif. transcripts encoding sHsps expressed in the codling moth cell line, Cp169, subjected to heat shock. Three f.ll-length cDNAs were cloned f.om Cp169 cells that contained open reading f.ames encoding sHsps. The cDNA f.r CpHsp 19.8 was 795 bp encoding 177 amino acids. The cDNA f.r CpHsp 19.9 was 749 bp encoding 175 amino acids. The cDNA f.r CpHsp22.2 was 737 bp encoding 192 amino acids. Analysis of.the protein sequences of.the three CpHsps indicated the presence of.83 amino acids with homology to the α-crystallin domain. f.r each of.the CpHsps, the α-crystallin domain was surrounded by divergent N- and C-terminal regions, consistent with the conserved structural f.atures of.sHsps. Real-time polymerase chain reaction, used to determine the expression patterns of.each of.the sHsps in dif.erent developmental stages of.codling moth revealed the presence of.transcripts in all stages tested. Consistent with characteristics of.other sHsps, expression of.CpHsp transcripts were greatly enhanced when insects were subjected to heat shock. The results of.this research can be used as a guide to study the roles of.sHsps in codling moth control using various post-harvest treatments.

关键词： α-crystallin domain heat shock response qPCR

Ancient road transport devices： Developments f.om the Bronze Age to the Roman Empire

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f.ontiers of.Mechanical Engineering 2016年第1期11卷 12-25页

作者： Cesare ROSSI thomas G. CHONDROS Kypros f. MILIDONIS Sergio SAVINO f.avio RUSSO Department of.Industrial Engineering University of Naples 'Federico II' Naples 80125 Italy Mechanical Engineering & Aeronautics Department University of Patras Patras 26500 Greece USSME Consultant via Lamaria 137 Torte del Greco Napoli Italy

The development of.transportation systems has signif.cantly enhanced the welf.re and modernization of.society. Wooden vehicles pulled by animals have been used f.r land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating f.om the East were depicted in early Cretan seal-rings of.the same period. The two-wheeled horse- drawn chariot was one of.the most important inventions in history. This vehicle provided humanity its f.rst concept of.personal transport and was the key technology of.war f.r 2000 years. Chariots of.Mycenaean and Archaic Greece with light and f.exible f.ur-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of.this vehicle incorporated the seeds of.a primitive design activity and was important f.r engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the f.rst known machines on a wheeled base transported by horses or self.powered. Ancient engineers invented bearings lubricated with f.t, and Romans introduced the ancestors of.ball bearings f.r their wagons and carts. The historic evolution of.wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of.typically reconstructed wheeled transportation systems in ancient times. Traction requirements both f.r horse-driven machines and the power f.r internal motors are also analyzed. This study can serve as a basis f.r f.rther development of.detailed reconstruction of.transportation systems in antiquity.

关键词： transportation wheel spoke cart axle bearing

Membrane progesterone receptors(mPRs/PAQRs)in Schwann cells represent a promising target f.r the promotion of.neuroregeneration

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Neural Regeneration Research 2021年第2期16卷 281-282页

作者： Luca f.Castelnovo Peter thomas Valerio Magnaghi Marine Science Institute University of Texas at AustinPort AransasTXUSA Department of.Pharmacological and Biomolecular Sciences Universitàdegli Studi di MilanoMilanItaly

Schwann cells and neuroregeneration:Peripheral nerve injury is a common cause of.morbidity,which af.ects millions of.people *** peripheral nervous system,dif.erently f.om the central nervous system,has an intrinsic ability to regenerate af.er ***,in most cases the regenerative outcome is not completely satisf.ctory,in particular f.r long-gap peripheral nerve injuries in which the microsurgical approach is not *** these cases。

关键词： injuries progesterone cases

The embryology of.persistent cloaca and urogenital sinus malf.rmations

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Asian Journal of.Andrology 2020年第2期22卷 124-128页

作者： David f.M thomas University of.Leeds LeedsWest Yorkshire LS29JTUK

Cloacal malf.rmations are characterized by the conf.uence of.the lower urinary tract,the f.male reproductive tract,and the rectum to create a common channel with a single opening on the *** presence of.a cloaca is a normal phase of.early human embryological *** the 4^th and 7^th weeks of.gestation,the cloaca undergoes subdivision to f.rm the hindgut and urogenital *** of.this process results in the congenital anomaly termed persistent cloaca(PC).The term urorectal septum malf.rmation sequence(URSMS)is also used to describe this *** classic description of.this process which is still cited in many standard textbooks dates f.om the 19th ***,this has been increasingly called into question by the f.ndings of.studies using modern scientif.c *** sinus anomalies are def.ned by the conf.uence of.the urethra and vagina to f.rm a common channel of.varying length with a single perineal *** this condition,the anorectal canal opens separately on the *** presence of.a urogenital sinus represents a transient phase of.the normal development of.the lower genital tract in the f.male ***,the f.rm of.urogenital sinus most commonly encountered in the developed world is a f.ature of.disordered sexual dif.erentiation and does not arise simply f.om the persistence of.the anatomical structure which is a f.ature of.normal f.tal development.

关键词： cloaca embryology urogenital sinus

TopSTO:a 115-line code f.r topology optimization of.structures under stationary stochastic dynamic loading

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 1081-1100页

作者： Sebastian Pozo f.rnando Gomez thomas Golecki Juan Carrion Billie f.Spencer Jr. Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbana 61801ILUSA College of.Science and Engineering Universidad San Francisco de QuitoDiego de Robles y Vía InteroceanicaQuitoEcuador Skidmore Owings&MerrillLLPChicago 60604ILUSA Department of.Civil Engineering University of CuencaCuencaEcuador

The use of.topology optimization in structural design under dynamic excitation is becoming more prevalent in the *** many such applications utilize f.equency or time domain f.rmulations,relatively f.w consider stochastic dynamic *** paper presents an ef.icient and compact code called TopSTO f.r structural topology optimization considering stationary stochastic dynamic loading using a method derived f.om random vibration *** theory,described in conjunction with the implementation in the provided code,is illustrated f.r a seismically excited *** work demonstrates the ef.iciency of.the approach in terms of.both the computational resources and minimal amount of.code *** code is intended to serve as a baseline f.r understanding the theory and implementation of.this topology optimization approach and as a f.undation f.r additional applications and developments.

关键词： topology optimization stochastic dynamics matlab python

Hydrothermal carbonization of.livestock mortality f.r the reduction of.pathogens and microbially-derived DNA

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f.ontiers of.Environmental Science & Engineering 2017年第3期11卷 107-114页

作者： thomas f. Ducey Jessica C. Collins Kyoung S. Ro Bryan L. Woodbury D. Dee Grif.in Coastal Plains Soil Water and Plant Research Center Agricultural Research Service United States Department of Agriculture Florence SC 29501 USA South Carolina Governor's School f.r Science and Mathematics Hartsville SC 29550 USA U.S. Meat Animal Research Center Agricultural Research Service United States Department of Agriculture Clay Center NE 68933 USA University of.Nebraska-Lincoln Great Plains Veterinary Education Center Lincoln NE 68588 USA

Hydrothermal carbonization （HTC）, utilizing high temperature and pressure, has the potential to treat agricultural waste via inactivating pathogens, antibiotic resistance genes （ARG）, and contaminants of.emerging concern （CEC） in a environmental and economical manner. Livestock mortality is one f.cet of.agricultural waste that can pose a threat to the surrounding environment. While several methods are utilized to treat livestock mortality, there remains a paucity of.data on the elimination of.microbially- derived DNA in these treatment practices. This DNA, most notably ARGs, if.it survives treatment can be reintroduced in agricultural environments where it could potentially be passed to pathogens, posing a risk to animal and human populations. HTC treatments have been successf.lly utilized f.r the treatment of.CECs, however very little is understood on how ARGs survive HTC treatment. This study aims to f.ll this knowledge gap by examining the survivability of.icrobially-derived DNA in the HTC treatment of.livestock mortality. We examined three treatment temperatures （100℃, 150℃, and 200℃） at autogenic pressures at three treatment times （30, 60, and 240 min）. We examined the amplif.cation of.a plasmid-bome reporter gene carried by Escherichia coli DH 10B introduced to both beef.bone and tissue. Results indicate that while all three temperatures, at all treatment times, were suitable f.r complete pathogen kill, only temperatures of.150℃ and 200℃ were suf.icient f.r eliminating microbial DNA. These results serve as the basis f.r f.ture potential HTC treatment recommendations f.r livestock mortality when considering the elimination of.pathogens and ARGs.

关键词： High-temperature carbonization Microbial DNA Livestock mortality