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Forces and energetics of intermittent swimming

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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

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General Eschatology and the Pastoral Task

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金陵神学志 2003年第4期 17-31页

作者： Richard j. mouw

Eschatology is the study of 'last things.' It is that sub-discipline of theology that focuses on what we can know about how God’s plan for the creation, as we know it will be brought to a culmination. Eschatology is typically divided into two areas of study: general eschatology and individual eschatology. The former deals with the overall patterns of how God’s redeeming purposes history will move toward the final transformation of all

关键词： General Eschatology and the Pastoral Task 金陵神学志

Aging gracefully: social engagement joins 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 Injury 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 major 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

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

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World journal 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

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 jSmart Kejun Li junqing 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： jeremy j.jorgensen john E.Christensen tyler j.jarvis 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

Fungi for future foods

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journal of Future Foods 2021年第1期1卷 25-37页

作者： tyler j.Barzee Lin Cao Zhongli Pan Ruihong Zhang Deparment of Biosytems and Agricuitural Engineering Universiny of Kenucky128 CE Bamhart Building.LexingtonKr40546-0276.USA Deparnment of Biological and Agricultural Engineering Thriversity of Califomnia DanisOme Shields AvemueDarisCA95616USA

The rapid growth of human civilizations has 1ed to imminent pressures to develop new food products with increased nutitiona1 characteristics and decreased environmenta1 *** fungi,a class of microorganisms that have been utilized in a wide variety of foods for thousands of years,have recently gamered widespread attention in research communities and commercia1 ventures seeking to explore new and innovative applications in a diverse aray of food products including,but not 1imited to,their more established applications as alterative *** advances in the cultivation and processing of flamentous fungi have created new frontiers in the control of textures,flavors,and nutritional properties of fungi-based *** review highlights technological advances in the production of fungi-based foods from cultivation to product manufacturing,presents the current state of the ant in fungi-based food products,and offters thoughts on their future *** is given to circular bioprocessing concepts for the sustainable utilization of agricultural and food processing byproducts.

关键词： Filamentous fungi Mycoprotein Fermentation 3D printing Biomanufacturing Nove1 foods

Witten's D_4 Integrable Hierarchies Conjecture

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Chinese Annals of Mathematics,Series B 2016年第2期37卷 175-192页

作者： Huijun FAN Amanda FRANCIS tyler jARVIS Evan MERRELL Yongbin RUAN School of Mathematical Sciences Peking University Department of Mathematics Brigham Young University Department of Mathematics University of Michigan Ann Arbor the Yangtz Center of Mathematics at Sichuan University

The authors prove that the total descendant potential functions of the theory of Fan-jarvis-Ruan-Witten for D4 with symmetry group j and for D4T with symmetry group Gmax, respectively, are both tau-functions of the D4 Kac-Wakimoto/Drinfeld-Sokolov hierarchy. This completes the proof, begun in the article by Fan-jarvis-Ruan（2013）, of the Witten Integrable Hierarchies Conjecture for all simple（ADE） singularities.

关键词： Quantum cohomology Frobenius manifolds Singularity theory Integrable hierarchies

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