检索结果-南通市图书馆

电子产品世界 2001年第13期 53-55页

作者： doug davis 桦

The Quantum Consistency of the Ten-Dimensional Heterotic String Effective Action

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2011年第5期55卷 857-862页

作者： Simon davis Research Foundation of Southern California

The finiteness of superstring theory at each order in perturbation theory is considered with respect to the ten-dimensional effective action. The quantum consistency of the ten-dimensional superstring effective action is confirmed with an analysis of the perturbative expansion of the quartic sector. It is found to be compatible with the finiteness of reduced four-dimensional theory. Furthermore, implications for the validity of superstring perturbation theory at lower energies is considered.

关键词： effective action gauge potential renormalizability

Univalent Functions and Diff(S^1)/S^1

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2012年第6期28卷 1233-1236页

作者： Simon davis Research Foundation of Southern California

The relation between Diff（S^1）/S^1 and the space of univalent analytic functions on the disk is elucidated and shown to provide upper bounds for the volumes of exhaustive approximations to an analytic submanifold of an infinite-dimensional space. The maximum magnitudes of the coefficients in the series expansions of univalent superanalytic functions on the superdisk are inferred.

关键词： Univalent diffeomorphism group superanalytic functions

Holomorphic Factorization of Superstring Scattering Amplitudes

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2011年第1期55卷 1-5页

作者： Simon davis Research Foundation of Southern Califoria

The holomorphic factorization of the superstring partition function is verified at arbitrary genus. The evaluation of scattering amplitudes and the implications of genus-dependent estimates on the string coupling are ... 详细信息

关键词： holomorphic factorization Ramond measure supermoduli space coordinate

Discrete composition control of two-dimensional morphologic all-inorganic metal halide perovskite nanocrystals

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第8期30卷 257-275,I0006页

作者： Andrew Hunter davis Weiwei Zheng Department of Chemistry Syracuse University13244 SyracuseUnited States

Metal halide perovskite nanocrystals(NCs)exhibit impressive optical and electronic properties,making them an important class of functional materials with promising applications in solar cells,light emitting diodes(LEDs),photodetectors,and *** addition to the widely studied 0-dimensional(0 D)metal halide perovskite NCs,such as nanocubes,low dimensional perovskites,such as 2 D all-inorganic perovskite(AIP)NCs,subsist with directionally relevant quantum *** anisotropic NCs have the propensity to exhibit interesting optoelectronic properties that are exceedingly difficult to introduce into 0 D systems,yet as of late are largely *** this review,we discuss the recent synthetic progress of 2 D all-inorganic metal halide perovskite NCs with ABX3 ***,we highlight the discrete composition control of the cations(A and B sites)and anions(X site)by dopant incorporation and alloying in 2 D metal halide perovskite *** will also discuss more complex perovskite crystal structures,such as Ruddlesden-Popper double perovskites,and compare these materials to 0 D perovskite ***,our work culminates in the future interests and perspectives of this field with a focus on the wide applicability of 2 D systems and the large variance in structure capable with discrete compositional tuning.

关键词： All-inorganic perovskites Two-dimensional nanocrystals Composition Doping Alloying Ion exchange

INVESTIGATION OF THE ATRP OF n-BUTYL METHACRYLATE USING THE Cu(I)/N,N,N',N",N"-PENTAMETHYLDIETHYLENETRIAMINE CATALYST SYSTEM

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2004年第2期22卷 195-204页

作者： Kelly A. davis Krzysztof Matyjaszewski Center for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USACenter for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USA

The polymerization of n-butyl methacrylate was investigated using the Atom Transfer Radical Polymerization technique with CuBr and CuCl/N,N,N',N',N'-pentamethyldiethylenetriamine catalytic systems. Various combinations of catalyst systems and initiators were utilized in order to optimize the polymerization conditions and to obtain well-defined polymers (i.e. controlled molecular weights and low polydispersities). It has been found that the optimal initiator for this system is a chlorine-based initiator, when the catalyst used is a salt in conjunction with the N,N,N',N',N'- pentamethyldiethylenetriamine ligand. Bromine-based initiators tend to result in large amounts of initial termination, leading to polymers with less than ideal chain end functionality, even if CuCl is used as the species to invoke the halogen exchange. Additionally, the effects of the polymerization temperature, species and the initiator structure were determined.

关键词： ATRP Atom transfer radical polymerization Controlled/living radical polymerization Butyl methacrylate Pentamethyldiethylenetriamine

DISCONTINUOUS GALERKIN CALCULATIONS FOR A NONLINEAR PDE MODEL OF DNA TRANSCRIPTION WITH SHORT, TRANSIENT AND FREQUENT PAUSING

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2014年第6期32卷 601-629页

作者： Lisa davis Tomas Gedeon Department of Mathematical Sciences Montana State University P.O. Box 172400 Bozeman MT 59717

A discontinuous Galerkin finite element method is used to approximate solutions to a classical traffic flow PDE. This PDE is used to model the biological process of transcription; the process of transferring genetic information from DNA either to mRNA or to rRNA. The transcription process is punctuated by short, frequent RNAP pauses which are incorporated into the model as traffic lights. These pauses cause a delay in the average transcription process. The DG solution of the nonlinear model is used to calculate the delay and to determine the effect of the pauses on the average transcription time. Numerical error measurements between the DG solution and the true solution （derived by the method of characteristics） are given for a simple model problem. It shows an excellent agreement in a neighborhood away from the shocks as well as C9（Ax） convergence for the delay calculation. Preliminary parameter studies indicate that in a system with multiple pauses both the location and time duration of the pauses can significantly affect the average delay experienced by an RNAP.

关键词： Discontinuous Galerkin finite element method Transcription LWR traffic flowmodel.

Do black-furred animals compensate for high solar absorption with smaller hairs？ A test with a polymorphic squirrel species

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2011年第6期57卷 731-736页

作者： Melanie A. FRATTO Andrew K. davis Odum School of Ecology The University of Georgia Athens GA USA 30602

In polymorphic mammalian species that display multiple color forms, those with dark, or melanic pelage would be prone to overheating, especially if they live in warm climates, because their fur absorbs solar energy at a higher rate. However, experimental studies indicate that certain physical properties of fur of dark individuals appear to prevent, or minimize heat stress, although it is not clear what properties do so. Here, we tested the possibility that black-furred individuals simply have shorter or thinner hair fibers, which would create a lighter （in terms of weight） coat or one that allows greater air flow for evaporative coo- ling. We examined museum specimens of eastern fox squirrels Sciurus niger, a species native to the United States and one that displays brown, grey or all-black pelage color, and used image analysis procedures to quantify hairs from the dorsal surface and tail. From examination of 43 specimens （19 brown, 9 black and 15 grey）, and 1,720 hairs, we found no significant difference in hair lengths across color morphs, but significant differences in hair fiber widths. Black squirrels had thinner body hairs than other forms （7% thinner）, but thicker tail hairs （9% thicker） than the others. Given that the dorsal surface would be directly exposed to solar radiation, we interpret this to be an adaptation to prevent heat stress during the day. The thicker tail hairs may be an adapta- tion for nighttime thermoregulation, since squirrels sleep with their tails wrapped around their bodies. These results add to a growing literature body of the functional significance of mammalian pelage [Current Zoology 57 （6）： 731-736, 2011].

关键词： Polymorphism Melanism Fox squirrels Sciurus niger Heat stress Hair morphology

Regulation of protein degradation pathways by amino acids and insulin in skeletal muscle of neonatal pigs

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2014年第3期5卷 299-309页

作者： Agus Suryawan Teresa A davis United States Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center Department of PediatricsBaylor College of Medicine

Background： The rapid gain in lean mass in neonates requires greater rates of protein synthesis than degradation. We previously delineated the molecular mechanisms by which insulin and amino acids, especially leucine, modulate skeletal muscle protein synthesis and how this changes with development. In the current study, we identified mechanisms involved in protein degradation regulation. In experiment 1,6- and 26-d-old pigs were studied during 1） euinsulinemic-euglycemic-euaminoacidemic, 2） euinsulinemic-euglycemiohyperaminoacidemic, and 3） hyperinsulinemic-euglycemic-euaminoacidemic clamps for 2 h. In experiment 2, 5-d-old pigs were studied during 1） euinsulinemic-euglycemic-euaminoacidemic-euleucinemic, 2） euinsulinemic-euglycemic-hypoaminoacidemic- hyperleucinemic, and 3） euinsulinemic-euglycemic-euaminoacidemic-hyperleucinemic clamps for 24 h. We determined in muscle indices of ubiquitin-proteasome, i.e., atrogin-1 （MAFbx） and muscle RING-finger protein-1 （MuRF1） and autophagy-lysosome systems, i.e., unc51-1ike kinase 1 （UKL1）, microtubule-associated protein light chain 3 （LC3）, and lysosomal-associated membrane protein 2 （Lamp-2）. For comparison, we measured ribosomal protein 56 （rpS6） and eukaryotic initiation factor 4E （elF4E） activation, components of translation initiation. Results： Abundance of atrogin-1, but not MuRF1, was greater in 26- than 6-d-old pigs and was not affected by insulin, amino acids, or leucine. Abundance of ULK1 and LC3 was higher in younger pigs and not affected by treatment. The LC3-11/LC3-1 ratio was reduced and ULK1 phosphorylation increased by insulin, amino acids, and leucine. These responses were more profound in younger pigs. Abundance of Lamp-2 was not affected by treatment or development. Abundance of elF4E, but not rpS6, was higher in 6- than 26-d-old-pigs but unaffected by treatment. Phosphorylation of elF4E was not affected by treatment, however, insulin, amino acids, and leucine stimulated rpS6 phosphorylation, and the resp

关键词： Amino acids Autophagy Insulin Leucine Muscle Neonate Protein degradation Protein synthesis,Swine Ubiquitin

Vaccine-associated myocarditis:a case report and summary of the literature

在线全文

学校读者我要写书评

暂无评论

World Journal of Emergency Medicine 2022年第6期13卷 485-487页

作者： Joshua davis Lauren Jennings University of Kansas School of Medicine Wichita 67214USA Vituity Wichita 67214USA American Red Cross in Hazelwood Missouri 63042USA

Dear editor,Myocarditis is a known complication of vaccines for COVID-19,particularly mRNA *** it is rare,the exact incidence of vaccine-associated myocarditis is *** of personal choice in vaccination decisions often cite the risk of myocarditis as a reason one might choose not to receive the COVID-19 ***,we describe a case of focal myocarditis associated with the Pfizer-BioNTech COVID-19 vaccine and review the literature on the incidence and risk of COVID-19 vaccine-associated myocarditis.

关键词： myocarditis vaccine Pfizer