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Covariance estimation via fiducial inference

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statistical Theory and Related Fields 2021年第4期5卷 316-331页

作者： W.jenny shi Jan Hannig Randy C.s.Lai Thomas C.M.Lee Financial Planning&Analysis MassMutualBostonMAUSA Department of statistics&Operations Research University of North CarolinaChapel HillNCUSA Department of statistics University of CaliforniaDavisCAUSA

As a classical problem,covariance estimation has drawn much attention from the statistical com-munity for *** work has been done under the frequentist and Bayesian *** to quantify the uncertainty of the estimators without having to choose a prior,we have developed a fiducial approach to the estimation of covariance *** upon the Fiducial Berstein-von Mises Theorem,we show that the fiducial distribution of the covariate matrix is consistent under our ***,the samples generated from this fiducial distri-bution are good estimators to the true covariance matrix,which enable us to define a meaningful confidence region for the covariance ***,we also show that the fiducial approach can be a powerful tool for identifying clique structures in covariance matrices.

关键词： covariance estimation sparsity fiducial inference cliques

Current concepts in microsurgical soft tissue reconstruction of lower extremity trauma in a single-vessel extremity

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Plastic and Aesthetic Research 2022年第1期9卷 171-181页

作者： jenny L.Yu Philip D.Tolley Cameron Kneib Erin A.Miller Christopher s.Crowe Division of Plastic surgery University of WashingtonSeattleWA 98104United States

Advancements in microsurgical techniques have allowed for the salvage of extremities that would otherwise be *** these improvements,mangling injuries of the lower extremity with concomitant open fracture continue to present a challenge for reconstructive *** injuries are further complicated by circumstances in which a single vessel is perfusing the foot after trauma(Gustilo 3C injuries).Although the foot may remain perfused in this instance,free flap coverage of open fractures with concomitant vascular injury requires careful planning to maintain a viable *** surgeon must adapt surgical plans based on both preoperative and intraoperative *** this review,we discuss current concepts and reconstructive techniques for performing free flap reconstruction in single-vessel lower extremities.

关键词： Lower extremity reconstruction microsurgery

smooth muscle cell differentiation： Mechanisms and models for vascular diseases

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Frontiers in Biology 2017年第6期12卷 392-405页

作者： Yujie Deng Caixia Lin Huanjiao jenny Zhou Wang Min Center for Translational Medicine The First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 China Department of Pathology and the Vascular Biology and Therapeutics Program Yale University Sehool of Medicine New Haven CT 06520USA

Background Vascular smooth muscle cells (VsMCs) are mature cells that play critical roles in both normal and aberrant cardiovascular conditions. In response to various environmental cues, VsMCs can dedifferentiate from a contractile state to a highly proliferative synthetic state through the so-called ‘phenotypic switching’ process. Changes in VsMC phenotype contribute to numerous vascular-related diseases, including atherosclerosis, calcification, and restenosis following angioplasty. Adventitial VsMC progenitor cells also contribute to formation of the ***/Results Herein, we review both, the roles of VsMC differentiation in vascular diseases, and the in vitro models used to investigate the molecular mechanisms involved in the regulation of VsMC differentiation and phenotype *** A comprehensive understanding of VsMC behavior in vascular diseases is essential to identify new therapeutic targets for the prevention and treatment of cardiovascular diseases.

关键词： vascular smooth muscle cells progenitor differentiation transcription factor cardiovascular disease

Valuing options to renew at future market value:the case of commercial property leases

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Financial Innovation 2023年第1期9卷 1932-1966页

作者： jenny Jing Wang Jianfu shen Frederik Pretorius Department of Real Estate and Construction The University of Hong KongPokfulamHong KongSAR Department of Building and Real Estate The Hong Kong Polytechnic UniversityHum HongHong KongSAR

In this study,we develop and empirically test a valuation model for a commonly encountered option in office leases:a tenant’s option to renew at future market rent(a fair market value)with lease termination as the maturity *** model integrates decision analysis with real options analysis and market risk with private risks.“Option value”is defined as the private value of the option to either party pre-contract,while“option price”assumes a fair agreement between transacting parties and can be positive(rental premium paid)or negative(rental discount offered).Without manifest expectations,an analysis of a sample of office leases supports the model’s logic with price estimates in a practical *** tenants’option price/value is shown to have a negative relationship with the original/renewal lease term;conversely,the landlords’option value is positively related to the original/renewal *** analyses show that transaction costs have a positive effect on tenants’option value and on prices,while vacancy costs and the vacancy period are both positively related to the landlords’option value and negatively related to *** rent is found to have a negative relationship with option ***,this study provides a theoretical analysis and empirical tests of the value of a real option that allows option holders to renew/extend their contracts at a fair market value.

关键词： Fair market value renewal Commercial property leases Real option Valuation Integrated method

The relationship of high-intensity cross-training with arterial stiffness

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Journal of sport and Health science 2019年第4期8卷 370-375页

作者： Jamie F.Burr jenny L.Beck John J.Durocher Department of Human Health and Nutritional sciences University of GuelphGuelphON NIG 2W1Canada Applied Human sciences University of Prince Edward IslandCharlottetownPE CIA 4P3Canada Department of Biological sciences Michigan Technological UniversityHoughtonMI 49931USA

Background'.Central arterial stiffness is a cardiovascular risk factor that can be readily affected through engagement in physical exercise training,with resistance and aerobic exercise having disparate *** the growing popularity of high-intensity cross-training(HICT),little is currently known about the effects of this mixed modality exercise stimulus on arterial ***,the purpose of this study was to characterize the arterial stiffness of habitual HICT participants *** active and sedentary controls using a cross-sectional ***'.A total of 30 participants were recruited:10 middle-aged long-term participants of HICT(CrossFit)and 20 age,sex,and height matched controls(10 recreationally active,10 sedentary).Central and peripheral pulse wave velocities were measured for the carotid-femoral and femoral-dorsalis pedis arterial *** fitness(maximal oxygen uptake,VChmax)was measured and typical exercise participation rates were self-reported for each ***'.HICT participants manifested central pulse wave velocity(PWV)(5.3±1.0 m/s,mean±sD)and VChmax(43±6 mL/kg/min)values nearly identical to active *** active groups had significantly better values than sedentary controls(7.1±1.0 m/s,p≤0.001;and 32±7 mL/kg/min,p=0.01).No differences were observed in peripheral PWV between ***'.Habitual participation in HICT exercise was not associated with increased central nor peripheral arterial ***-term HICT participants presented with similar fitness and arterial stiffness as compared with participants who practiced traditional aerobic *** to sedentary living,HICT may offer musculoskeletal and cardiovascular health benefits without negatively impacting arterial stiffness.

关键词： Circuit training CrossFit Pulse wave velocity Resistance exercise Vascular Weight training

A sTUDY OF sTRUCTURE AND PROPERTY CHANGEs OF BIODEGRADABLE POLYGLYCOLIDE AND POLY(GLYCOLIDE-co-LACTIDE)FIBERs DURING PROCEssING AND IN VITRO DEGRADATION

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Chinese Journal of Polymer science 2003年第2期21卷 159-167页

作者： Bruce X.Fu Benjamin s.Hsiao Gavin Chen Jack Zhou susan Lin jenny Yuan Ilya Koyfman Dennis D Jamiolkowski Edward Dormier Department of Chemistry State University of New York at Stony Brook Stony BrookNY 11794-3400 USA Ethicon Worldwide A Johnson & Johnson Company P. O. Box 151 Somerville. New Jersey 08876-0151 USA

structure and properties of bioabsorbable polyglycolide (PGA) and poly(glycolide-co-lactide) (PGA-co-PLA)fibers were investigated during several industrial processing stages and in vitro degradation by means of wide-angle X-raydiffraction (WAXD), dynamic mechanical analysis (DMA) and mechanical property tests. In the orientation stage, the PGAfibers were found to have higher degrees of crystallinity than corresponding PGA-co-PLA samples produced under similarconditions. In the hot-stretching and post-annealing stages, after fibers were braided, PGA samples were found to gain morecrystallinity and higher T_g than PGA-co-PLA samples. The higher crystallinity in PGA fibers resulted in a slower rate ofdegradation. DMA results showed that a great deal of internal stress that was built during orientation and hot-stretchingstages was released in the post-annealing stage for a1l PGA and PGA-co-PLA samples. During earlier stages of in vitrodegradation, both PGA and PGA-co-PLA samples exhibited the typical cleavage-induced crystallization mechanism. Theheat shrinkage in the glass transition area was found to disappear after 6-8 days of degradation for all PGA and PGA-co-PLAsamples, indicating the amorphous portions of the polymers lost orientation after a short period in the buffer solution, mostlikely due to relaxation of the cleaved chains.

关键词： Polyglycolide Poly(glycolide-co-lactide) Bioabsorbable Fiber processing in vitro Degradation

stigmatic exudate in the Annonaceae:Pollinator reward,pollen germination medium or extragynoecial compitum?

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Journal of Integrative Plant Biology 2017年第12期59卷 881-894页

作者： jenny Y.Y.Lau Chun-Chiu Pang Lawrence Ramsden Richard M.K.saunders school of Biological sciences the University of Hong KongPokfulam RoadHong KongChina

Although ＂dry-type＂ stigmas are widely re- garded as ancestral in angiosperms, the early-divergent family Annonaceae has copious stigmatic exudate. We evaluate three putative functions for this exudate： as a nutritive reward for pollinators; as a pollen germination medium; and as an extragynoecial compitum that enables pollen tube growth between carpels. stigmatic exudate is fructose dominated （72.2%）, but with high levels of glucose and sucrose; the dominance of hexose sugars and the diversity of amino acids observed, including many that are essential for insects, support a nutritive role for pollinators. sugar concentration in pre-receptive flowers is high （28.2%）, falling during the peak period of stigmatic receptivity （17.4%）, and then rising again toward the end of the pistillate phase （32.9%）. Pollen germination was highest in sugar concentrations 〈2%. sugar concentrations during the peak pistillate phase therefore provide optimal osmolarity for pollen hydration and germination; subsequent changes in sugar concentration during anthesis reinforce protogyny （in which carpels mature before stamens）, enabling the retention of concentrated exudate into the staminate phase as a pollinator food reward without the possibility of pollen germination. Intercarpellary growth of pollen tubes was confirmed： the exudate therefore also functions as a suprastylar extragynoecial compitum, overcoming the limitations of apocarpy.

关键词： stigmatic exudate in the Annonaceae pollen germination medium or extragynoecial compitum Pollinator reward

Prognosis of lymphotropic invasive micropapillary breast carcinoma analyzed by using data from the National Cancer Database

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Cancer Communications 2019年第1期39卷 548-556页

作者： Gary D.Lewis Yan Xing Waqar Haque Tejal Patel Mary schwartz Albert Chen Andrew Farach sandra s.Hatch E.Brian Butler jenny Chang Bin s.Teh Department of Radiation Oncology University of Arkansas for Medical SciencesLittle RockAR 72205USA Department of Medicine Houston Methodist HospitalHoustonTX 77030USA Department of Radiation Oncology Houston Methodist HospitalHoustonTX 77030USA Department of Pathology and Genomic Medicine Houston Methodist HospitalHoustonTX 77030USA Department of Radiation Oncology Baylor College of MedicineHoustonTX 77030USA Department of Radiation Oncology The University of Texas Medical BranchGalvestonTX 77555USA

Background:Invasive micropapillary carcinoma(IMPC)is an uncommon subtype of breast *** studies of this subtype demonstrated a higher propensity for lymph node metastases as compared with invasive ductal carci-noma(IDC).The purpose of the present study was to determine the clinical characteristics,outcomes,and propensity for lymph node metastasis of patients with IMPC of the breast recorded in the National Cancer Database(NCDB).Methods:Records of patients with IMPC diagnosed between 2004 and 2014 were retrieved from the ***-rank test was performed to evaluate associations of clinical characteristics with overall survival(Os).Cox proportional hazards model was used to determine variables associated with ***:Overall,2660 patients with IMPC met the selection criteria;the 5-year Os rate was 87.5%and 24.9%of patients had nodal involvement at *** with≥4 positive lymph nodes had shorter Os than node-negative patients,whereas patients with 1-3 positive nodes had similar Os to node-negative ***s,receipt of radiotherapy,and estrogen receptor positivity were also associated with prolonged *** benefit of radiotherapy was limited to IMPC patients undergoing lumpectomy;there was no benefit for the patients undergoing mastectomy(regardless of nodal positivity/negativity).Conclusions:Favorable prognostic factors of IMPC patients included ages,sitive lymph nodes,receipt of radiotherapy,and estrogen receptor *** results presented herein suggest a survival benefit asso-ciated with radiotherapy in IMPC treatment,though this may be limited to the patients treated with lumpectomy.

关键词： Breast cancer Invasive micropapillary carcinoma Radiotherapy surgery survival Hormone receptor

Reconstructing and forecasting the COVID-19 epidemic in the United states using a 5-parameter logistic growth model

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Global Health Research and Policy 2020年第1期5卷 221-227页

作者： Ding-Geng Chen Xinguang Chen jenny K.Chen school of social Work University of North CarolinaTate-Turner Kuralt Building 548-CCB#3550Chapel HillNC 27599USA Department of statistics University of PretoriaPretoriaSouth Africa Department of Epidemiology University of FloridaGainesvilleUSA Department of statistics and Data science Cornell UniversityIthacaUSA

Background:Many studies have modeled and predicted the spread of COVID-19(coronavirus disease 2019)in the *** data that begins with the first reported ***,the shortage of testing services to detect infected persons makes this approach subject to error due to its underdetection of early cases in the *** new approach overcomes this limitation and provides data supporting the public policy decisions intended to combat the spread of COVID-19 ***:We used Centers for Disease Control and Prevention data documenting the daily new and cumulative cases of confirmed COVID-19 in the *** January 22 to April 6,2020,and reconstructed the epidemic using a 5-parameter logistic growth *** fitted our model to data from a 2-week window(i.e.,from March 21 to April 4,approximately one incubation period)during which large-scale testing was being *** parameters obtained from this modeling,we reconstructed and predicted the growth of the epidemic and evaluated the extent and potential effects of ***:The data fit the model *** estimated daily growth rate was 16.8%overall with 95%CI:[15.95,17.76%],suggesting a doubling period of 4 *** on the modeling result,the tipping point at which new cases will begin to decline will be on April 7th,2020,with a peak of 32,860 new cases on that *** the end of the epidemic,at least 792,548(95%CI:[789,162,795,934])will be infected in the *** on our model,a total of 12,029 cases were not detected between January 22(when the first case was detected in the U.s.)and April ***:Our findings demonstrate the utility of a 5-parameter logistic growth model with reliable data that comes from a specified period during which governmental interventions were appropriately *** informing public health decision-making,our model adds a tool for more faithfully capturing the spread of the COVID-19 epidemic.

关键词： COVID-19 Epidemics Disease dynamics Population-based model Logistic growth model Prediction Reconstruction Under-detection Tipping point UsA