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Conj.gate Addition of Indoles to α ,β -Unsaturated Ketones Using Bismuth (III) Bromide

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Forces and energetics of intermittent swimming

Green and Sustainable Chemistry（绿色与可持续化学） 2019年第3期

作者： tyler j. rauwolf Zhij.a Geng Zachary P. Kinney j.red L. Renfroe j.ck H. Roireau Lauren T. Yep Ram S. Mohan

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Acta Mechanica Sinica 2017年第4期33卷 725-732页

作者： Daniel Floryan tyler Van Buren Alexander j.Smits Department of Mechanical and Aerospace Engineering Princeton University Princeton NJ 08544 USA

Experiments are reported on intermittent swimming motions. Water tunnel experiments on a nominally two-dimensional pitching foil show that the mean thrust and power scale linearly with the duty cycle, from a value of 0.2 all the way up to continuous motions, indicating that individual bursts of activity in intermittent motions are independent of each other. This conclusion is corroborated by particle image velocimetry（PIV） flow visualizations, which show that the main vortical structures in the wake do not change with duty cycle. The experimental data also demonstrate that intermittent motions are generally energetically advantageous over continuous motions. When metabolic energy losses are taken into account, this conclusion is maintained for metabolic power fractions less than 1.

关键词： intermittent swimming maintained conclusion cycle thrust favorable producing aquatic circles

Aging gracefully: social engagement j.ins exercise and enrichment as a key lifestyle factor in resistance to age-related cognitive decline

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Neural Regeneration Research 2019年第1期14卷 39-42页

作者： tyler j.Dause Elizabeth D.Kirby Department of Psychology The Ohio State University Department of Neuroscience The Ohio State University Chronic Brain Inj.ry Program The Ohio State University

Cognitive impairment is a consequence of the normal aging process that effects many species, including humans and rodent models. Decline in hippocampal memory function is especially prominent with age and often reduces quality of life. As the aging population expands, the need for interventional strategies to prevent cognitive decline has become more pressing. Fortunately, several maj.r lifestyle factors have proven effective at combating hippocampal aging, the most well-known of which are environmental enrichment and exercise. While the evidence supporting the beneficial nature of these factors is substantial, a less well-understood factor may also contribute to healthy cognitive aging: social engagement. We review the evidence supporting the role of social engagement in preserving hippocampal function in old age. In elderly humans, high levels of social engagement correlate with better hippocampal function, yet there is a dearth of work to indicate a causative role. Existing rodent literature is also limited but has begun to provide causative evidence and establish candidate mechanisms. Summed together, while many unanswered questions remain, it is clear that social engagement is a viable lifestyle factor for preserving cognitive function in old age. Social integration across the lifespan warrants more investigation and more appreciation when designing living circumstances for the elderly.

关键词： aging age-related cognitive decline social engagement hippocampus cognitive enrichment exercise memory neurogenesis

Genetic factors that affect nonalcoholic fatty liver disease: A systematic clinical review

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World j.urnal of Gastroenterology 2016年第29期22卷 6742-6756页

作者： tyler j.Severson Siddesh Besur Herbert L Bonkovsky Department of Gastroenterology and Hepatology Wake Forest University NC Baptist Medical Center Abdominal Transplant Program Aurora St Luke’s Medical Center

AIM: To investigate roles of genetic polymorphisms in non-alcoholic fatty liver disease (NAFLD) onset, severity, and outcome through systematic literature ***: The authors conducted both systematic and specific searches of PubMed through December 2015 with special emphasis on more recent data (from 2012 onward) while still drawing from more historical data for background. We identified several specific genetic polymorphisms that have been most researched and, at this time, appear to have the greatest clinical significance on NAFLD and similar hepatic diseases. These were further investigated to assess their specific effects on disease onset and progression and the mechanisms by which these effects ***: We focus particularly on genetic polymorphisms of the following genes: PNPLA3, particularly the p. I148M variant, TM6SF2, particularly the p. E167K variant, and on variants in FTO, LIPA, IFNλ4, and iron metabolism, specifically focusing on HFE, and HMOX-1. We discuss the effect of these genetic variations and their resultant protein variants on the onset of fatty liver disease and its severity, including the effect on likelihood of progression to cirrhosis and hepatocellular carcinoma. While our principal focus is on NAFLD, we also discuss briefly effects of some of the variants on development and severity of other hepatic diseases, including hepatitis C and alcoholic liver disease. These results are briefly discussed in terms of clinical application and future potential for personalized ***: Polymorphisms and genetic factors of several genes contribute to NAFLD and its end results. These genes hold keys to future improvements in diagnosis and management.

关键词： Genetic polymorphisms Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis PNPLA3 TM6SF2 FTO Cirrhosis Iron metabolism

Simulations of a logistic-type model with delays for Chagas disease with insecticide spraying

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International j.urnal of Biomathematics 2017年第3期10卷 41-60页

作者： Nofe Al-Asuoad tyler Pleasant Meir Shillor Hrishikesh Munugala Daniel j. Coffield j.. Anna Maria Spagnuolo Department of Mathematics and Statistics Oakland University Rochester MI 48309 USA Harrison High School MI USA Novi High School Novi MI 48375 USA Mathematics Department University of Michigan-Flint Flint MI 48502 USA

This work studies and numerically simulates a logistic-type model for the dynamics of Chagas disease, which is caused by the parasite T. cruzi and affects millions of humans and domestic mammals throughout rural areas in Central and South America. A basic model for the disease dynamics that includes insecticide spraying was developed in Spagnuolo et al. （2010） [271 and consists of a delay-differential equation for the vectors and three nonlinear ordinary differential equations for the populations of the infected vectors, infected humans and infected domestic mammals. In this work, the vector equation is modified by using a logistic term with zero, one or two delays or time lags. The aim of this study is three-fold： to numerically study the effects of using different numbers of delays on the model behavior; to find if twice yearly insecticide spraying schedules improve vector control; and to study the sensitivity of the system to the delays in the case of two delays, by introducing randomness in the delays. It is found that the vector equation with different number of delays has very different solutions. The ＂best＂ day of spraying is the middle of Spring and twice annual sprayings cause only minor improvements in disease control. Finally, the model is found to be insensitive to the values of the delays, when the delays are randomly distributed within rather narrow intervals or ranges centered on the parameter values used in Coffield et al. （2014） [8].

关键词： Chagas disease logistic equation with delays epidemic dynamics nonlinear dynamical system simulations.

Radiographic features and behaviors of neuroendocrine tumors:can we j.dge a book by its cover?

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Hepatobiliary Surgery and Nutrition 2021年第4期10卷 573-574页

作者： tyler j.Mouw Charles R.Scoggins Hiram C.Polk JrMD Department of SurgeryDivision of Surgical OncologyUniversity of LouisvilleLouisvilleKYUSA

Gastrointestinal and pancreatic neuroendocrine tumors are uncommon diseases which can have a varied clinical *** category of tumor includes functional and non-functional variants and despite the common developmental pathway for the cells of origin,the tumor subtypes can demonstrate strikingly different *** to the rarity and heterogeneous courses of this family of tumors.

关键词： tumors neuroendocrine diseases

Intersystem crossing and exciton–defect coupling of spin defects in hexagonal boron nitride

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npj.Computational Materials 2021年第1期7卷 537-544页

作者： tyler j.mart Kej.n Li j.nqing Xu Yuan Ping Department of Physics University of CaliforniaSanta CruzCAUSA Lawrence Livermore National Laboratory LivermoreCAUSA Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCAUSA

Despite the recognition of two-dimensional(2D)systems as emerging and scalable host materials of single-photon emitters or spin qubits,the uncontrolled,and undetermined chemical nature of these quantum defects has been a roadblock to further *** the design of extrinsic defects can circumvent these persistent issues and provide an ultimate ***,we established a complete theoretical framework to accurately and systematically design quantum defects in wide-bandgap 2D *** this approach,essential static and dynamical properties are equally considered for spin qubit *** particular,many-body interactions such as defect–exciton couplings are vital for describing excited state properties of defects in ultrathin 2D ***,nonradiative processes such as phonon-assisted decay and intersystem crossing rates require careful evaluation,which competes together with radiative *** a thorough screening of defects based on firstprinciples calculations,we identify promising single-photon emitters such as SiVV and spin qubits such as TiVV and MoVV in hexagonal boron *** work provided a complete first-principles theoretical framework for defect design in 2D materials.

关键词： defect hexagonal boron

Mechanistic insights of enhanced spin polaron conduction in CuO through atomic doping

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npj.Computational Materials 2018年第1期4卷 154-161页

作者： tyler j.Smart Allison C.Cardiel Feng Wu Kyoung-Shin Choi Yuan Ping Department of Physics University of CaliforniaSanta CruzCA 95064USA Department of Chemistry University of WisconsinMadisonWI 53706USA Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCA 95064USA

The formation of a“spin polaron”stems from strong spin-charge-lattice interactions in magnetic oxides,which leads to a localization of carriers accompanied by local magnetic polarization and lattice *** example,cupric oxide(CuO),which is a promising photocathode material and shares important similarities with high Tc superconductors,conducts holes through spin polaron hopping with flipped spins at Cu atoms where a spin polaron has *** formation of these spin polarons results in an activated hopping conduction process where the carriers must not only overcome strong electron−phonon coupling but also strong magnetic ***,these effects cause low carrier conduction in CuO and hinder its *** overcome this fundamental limitation,we demonstrate from first-principles calculations how doping can improve hopping conduction through simultaneous improvement of hole concentration and hopping mobility in magnetic oxides such as ***,using Li doping as an example,we show that Li has a low ionization energy that improves hole concentration,and lowers the hopping barrier through both the electron−phonon and magnetic couplings'reduction that improves hopping ***,this improved conduction predicted by theory is validated through the synthesis of Li-doped CuO electrodes which show enhanced photocurrent compared to pristine CuO *** conclude that doping with nonmagnetic shallow impurities is an effective strategy to improve hopping conductivities in magnetic oxides.

关键词： conduction doping polaron

A General Algorithm for Calculating Irreducible Brillouin Zones

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Communications in Computational Physics 2022年第2期31卷 495-515页

作者： j.remy j.j.rgensen j.hn E.Christensen tyler j.j.rvis Gus L.W.Hart Department of Physics and Astronomy Brigham Young UniversityProvoUtah84602USA Department ofMathematics BrighamYoungUniversityProvoUtah84602USA

Calculations of properties of materials require performing numerical integrals over the Brillouin zone(BZ).Integration points in density functional theory codes are uniformly spread over the BZ(despite integration error being concentrated in small regions of the BZ)and preserve symmetry to improve computational *** points over an irreducible Brillouin zone(IBZ),a rotationally distinct region of the BZ,do not have to preserve crystal symmetry for greater *** freedom allows the use of adaptive meshes with higher concentrations of points at locations of large error,resulting in improved algorithmic *** have created an algorithm for constructing an IBZ of any crystal structure in 2D and *** algorithmuses convex hull and half-space representations for the BZ and IBZ to make many aspects of construction and symmetry reduction of the BZ *** algorithm is simple,general,and available as open-source software.

关键词： Brillouin zone irreducible Brillouin zone