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The Moduli Space in the Gauged Linear Sigma Model

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Chinese Annals of Mathematics,Series B 2017年第4期38卷 913-936页

作者： Huijun FAN tyler jarvis Yongbin RUAN School of Mathematical Sciences Peking University Beijing 100871 China. Department of Mathematics Brigham Young University Provo UT 84602 USA. Department of Mathematics University of Michigan Ann Arbor MI 48105 USA.

This is a survey article for the mathematical theory of Witten's Gauged Linear Sigma Model, as developed recently by the authors. Instead of developing the theory in the most general setting, in this paper the authors... 详细信息

关键词： Landau-Ginzburg Calabi-Yau Gromov-Witten GLSM Moduli Phase Variation of geometric invariant theory Symplectic reduction

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

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

Diagnostic and therapeutic direct peroral cholangioscopy using an intraductal anchoring balloon

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World journal of Gastroenterology 2012年第30期18卷 3992-3996页

作者： Mansour A Parsi tyler Stevens john j Vargo Department of Gastroenterology and Hepatology Digestive Disease InstituteCleveland ClinicClevelandOH 44195United States

AIM:To report our experience using a recently introduced anchoring balloon for diagnostic and therapeutic direct peroral cholangioscopy(DPOC).METHODS:Consecutive patients referred for diagnostic or therapeutic peroral cholangioscopy were evaluated in a prospective cohort *** patients underwent DPOC using an intraductal anchoring balloon,which was recently introduced to allow consistent access to the biliary tree with an ultraslim upper *** device was later voluntarily withdrawn from the market by the ***:Fourteen patients underwent DPOC using the anchoring *** access with an ultraslim upper endoscope was accomplished in all 14 *** 12(86%) patients,ductal access required sphincteroplasty with a 10-mm dilating *** placement of the ultraslim upper endoscope allowed satisfactory visualization of the biliary mucosa to the level of the confluence of the right and left hepatic ducts in 13 of 14 patients(93%).Therapeutic interventions by DPOC were successfully completed in all five attempted cases(intraductal biopsy in one and DPOC guided laser lithotripsy in four).Adverse events occurred in a patient on immunosuppressive therapy who developed an intrahepatic biloma at the site of the anchoring *** required hospitalization and *** endoscopic retrograde cholangiopancreatography 8 wk after the index procedure showed resolution of the ***:Use of this anchoring balloon allowed consistent access to the biliary tree for performance of diagnostic and therapeutic DPOC distal to the biliary bifurcation.

关键词： Anchoring balloon Direct peroral cholangioscopy Cholangiocarcinoma Endoscopic retrograde cholangiopancreatography Choledocholithiasis

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

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

第二代欧洲玉米螟对不同玉米杂交种造成的产量损失

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国外农学-杂粮作物 1987年第3期 45-48页

作者： j.jarvis W.Guthrie 孙承钧

欧洲玉米螟(Ostrinia nubilalis)危害引起的玉米产量损失已有不少人进行过研究。一般认为玉米产量的损失随危害时期、危害时植株的发育阶段以及年份等不同而异。同样的条件下,抗性基因型的玉米产量损失较小。Chiang 等(1961)和 Hill 等(... 详细信息

欧洲玉米螟(Ostrinia nubilalis)危害引起的玉米产量损失已有不少人进行过研究。一般认为玉米产量的损失随危害时期、危害时植株的发育阶段以及年份等不同而异。同样的条件下,抗性基因型的玉米产量损失较小。Chiang 等(1961)和 Hill 等(1967、1973)曾

关键词：玉米杂交种虫孔漏收先锋卵块虫洞产量损失玉米螟第二代

Radiographic features and behaviors of neuroendocrine tumors:can we judge 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

Sperm fine-needle aspiration (FNA)mapping after failed microdissection testicular sperm extraction (TESE):location and patterns of found sperm

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Asian journal of Andrology 2019年第1期21卷 50-55页

作者： Sheba jarvis Heather K Yee Natalia Thomas Imok Cha Kedar Che Prasad jonathan W A Ramsay Paul j Turek Imperial College London Hammersmlth HospitalLondon W12 ONNUK The Turek Clinic San FranciscoCA 94133USA Marin Medical Laboratories Greenbrae CA 94904USA.

We sought to evaluate the ability of fine-needle aspiration (FNA)mapping to find sperm and to guide sperm retrieval after failed microdissection testicular sperm extraction (micro-TESE)in nonobstructive azoospermic *** this study of consecutive male infertility cases,interventions included testicular FNA mapping and subsequent sperm *** included the frequency and location of found sperm on FNA maps after failed micro-TESE and the salvage sperm retrieval *** 548 patients undergoing FNA mapping from 2010 to 2016,82 men with previous micro-TESE procedures were *** mean time between micro-TESE and FNA mapping was 2.2 years.A total of 2825 (1424 on right and 1401 on left)sites were *** least one site revealed mature sperm in 24 (29.3%)of 82 men with prior failed micro-TESE *** was an equal likelihood of detecting sperm in either testis (6.1%right;5.7%left;P=0.58).Digital "heat maps"revealed differences in sperm findings within the testis with mature sperm more likely found in the testis periphery rather than *** (62.5%)patients subsequently underwent sperm retrieval procedures guided by FNA *** sperm were retrieved in all cases,and in 10 (66.7%)of 15 cases,extra sperm were frozen for future *** a significant proportion of failed micro-TESE procedures representing the largest study to date,sperm were detected by FNA mapping and could be reliably retrieved through FNA map-guided surgical sperm *** present,sperm were more likely to be found in the testis periphery rather than centrally with FNA mapping.

关键词： azoospermia hypogonadism IVF-ICSI microdissection TESE sperm FNA mapping sperm retrieval