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STRONG CONVERGENCE RATES OF SEVERAL ESTIMATORS IN SEMIPARAMETRIC VARYING-COEFFICIENT PARTIALLY LINEAR MODELS

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Acta Mathematica Scientia 2009年第5期29卷 1113-1127页

作者：周勇尤进红王晓婧 Academy of Mathematics and Systems Science Chinese Academy of Science Department of Statistics Shanghai University of Finance and Economics Department of Biostatistics University of North Carolina at Chapel Hill Chapel Hill NC USA

This article is concerned with the estimating problem of semiparametric varyingcoefficient partially linear regression models. By combining the local polynomial and least squares procedures Fan and Huang （2005） proposed a profile least squares estimator for the parametric component and established its asymptotic normality. We further show that the profile least squares estimator can achieve the law of iterated logarithm. Moreover, we study the estimators of the functions characterizing the non-linear part as well as the error variance. The strong convergence rate and the law of iterated logarithm are derived for them, respectively.

关键词： partially linear regression model varying-coefficient profile leastsquares error variance strong convergence rate law of iterated logarithm

The modern testicular prosthesis:patient selection and counseling,surgical technique,and outcomes

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Asian Journal of Andrology 2020年第1期22卷 64-69页

作者： Solomon Hayon Jamie Michael R Matthew Coward Department of Urology University of North Carolina School of MedicineChapel HillNC 27500-7235USA University of North Carolina School of Medicine Chapel HillNC 27500-7235USA

The testicular prosthesis can be an afterthought for providers when performing an orchiectomy for testicular cancer,torsion,atrophic testis,or ***,data suggest that patients find the offer of a testicular prosthesis and counseling regarding placement to be extremely important from both a pragmatic and a psychosocial *** two-thirds of men undergoing orchiectomy are offered an implant at the time of orchiectomy and of those offered about one-third move forward with prosthesis *** relatively low acceptance rate is in stark contrast with high patient satisfaction and low complication rates for those who undergo the *** most common postoperative patient concerns are minor and involve implant positioning,size,and ***,we provide an up-to-date review of modern preoperative evaluation,patient selection,expectation management,surgical technique,and expected outcomes for testicular prostheses.

关键词： anorchia orchiectomy patient satisfaction prostheses and implants testicular neoplasms testis

A little goes a long way: CLE peptides mediate phloem initiation

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Journal of Integrative Plant Biology 2019年第10期61卷 1034-1035页

作者： Amala John Zachary L.Nimchuk Department of Biology University of North Carolina at Chapel Hill

The root system of a tree can often extend many-fold the diameter of the tree;it provides physical support, dissolved minerals and water but relies on a constant supply of nutrients from photosynthetically active tissues in aboveground organs. The phloem is re-sponsible for such transport and the success of a plant relies heavily on the integrity of the phloem in its root system.

关键词： CLE peptides mediate initiation

Structural, Visual, or Iconic： Transmutations of Wooden Brackets in Modern China

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Frontiers of History in China 2015年第2期10卷 323-365页

作者： Wei-Cheng Lin Department of Art University of North Carolina at Chapel Hill Chapel Hill NC 27599-3405 USA

Together with pillars and roof, the bracket set is one of the most fundamental structural components of traditional timber-frame architecture in China. Not only structurally indispensable, it was also emblematic of specific building styles developed through history. Entering the modem era, however, its architectural validity was overturned by the use of modem technology and building materials, rendering brackets merely a visual and decorative motif. This paper contends that it was precisely when the bracket set lost its structural significance that it began to be discussed in ways that endowed it with layers of cultural meaning in the context of modem China. Examining its modem appropriations in materials other than wood throughout the twentieth century, the paper explores shifting meanings of brackets in their continuous transmutations from a reminder of a defunct component in the building tradition to a nostalgic sign for an irretrievable architectural past.

关键词： brackets Liang Sicheng adaptive style timber-frame architecture,enchantment

Utility of combining spectral domain optical coherence tomography structural parameters for the diagnosis of early Glaucoma: a mini-review

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Eye and Vision 2018年第1期5卷 91-101页

作者： Jean-Claude Mwanza Joshua L.Warren Donald L.Budenz Department of Ophthalmology School of MedicineUniversity of North Carolina at Chapel HillChapel HillNCUSA Department of Biostatistics Yale UniversityNew HavenCTUSA

Optical coherence tomography(OCT)has moved to the forefront of imaging modalities in the management of glaucoma and retinal *** is modifying how glaucoma and glaucoma progression are diagnosed clinically and augmenting our understanding of the *** provides multiple parameters from various anatomic areas for glaucoma diagnosis,evaluation of treatment efficacy,and progression *** the use of multiple parameters has increased the likelihood of detecting early structural changes,diagnosing glaucoma in early stages is often challenging when the damages are subtle and not apparent on OCT scans,in addition to the fact that assessment of OCT parameters often yields conflicting *** promising approach is to combine multiple individual parameters into a composite parameter from the same test to improve diagnostic accuracy,sensitivity,and *** review presents current evidence regarding the value of spectral domain OCT composite parameters in diagnosing early glaucoma.

关键词： Optical coherence tomography Combination of parameters Early glaucoma

The role of intracellular protein O-glycosylation in cell adhesion and disease

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The Journal of Biomedical Research 2011年第4期25卷 227-236页

作者： Meryem Bektas David S.Rubenstein Department of Dermatology University of North Carolina-Chapel Hill School of MedicineChapel HillNorth Carolina 27599-7287USA Department of Pharmacology University of North Carolina-Chapel Hill School of MedicineChapel HillNorth Carolina 27599-7287USA Lineberger Comprehensive Cancer Center University of North Carolina-Chapel Hill School of MedicineChapel HillNorth Carolina 27599-7287USA

Post-translational protein modification, including phosphorylation, is generally quick and reversible, facilitating rapid biologic adjustments to altered cellular physiologic demands. In addition to protein phosphorylation, other post-translational modifications have been identified. Intracellular protein O-glycosylation, the addition of the simple sugar O-linked N-acetylglucosamine （O-G1cNAc） to serine/threonine residues, is a relatively recently identified post-translational modification that has added to the complexity by which protein function is regulated. Two intracellular enzymes, O-GlcNAc transferase and O-GlcNAcase, catalyze the addition and removal, respectively, of O-GlcNAc to serine and threonine side-chain hydroxyl groups. Numerous proteins, including enzymes, transcription factors, receptors and structural proteins have been shown to be modified by intracellular O-glycosylation. In this review, the mechanism and relevance of O-GlcNAc protein modification are discussed in the context of cell adhesion and several representative diseases.

关键词： O-glycosylation O-GlcNAc diabetes cancer cell adhesion

Acute liver failure due to natural killer-like T-cell leukemia/ lymphoma: A case report and review of the Literature

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World Journal of Gastroenterology 2006年第25期12卷 4089-4092页

作者： Evan S Dellon Shannon R Morris Wozhan Tang Cherie H Dunphy Mark W Russo Department of Medicine University of North Carolina School of Medicine Chapel HillNCUnited States Department of Pathology University of North Carolina School of Medicine Chapel HillNCUnited States

Acute liver failure （ALF） is a medical emergency requiring immediate evaluation for liver transplantation. We describe an unusual case of a patient who presented with ascites, jaundice, and encephalopathy and was found to have ALF due to natural killer （NK）-Iike T cell leukemia/lymphoma. The key immunophenotype was CD2＋, CD3＋, CD7＋, CD56＋. This diagnosis, which was based on findings in the peripheral blood and ascitic fluid, was confirmed with liver biopsy, and was a contraindication to liver transplantation. A review of the literature shows that hematologic malignancies are an uncommon cause of fulminant hepatic failure, and that NK-like T-cell leukemia/lymphoma is a relatively recently recognized entity which is characteristically CD3＋ and CD56＋. This case demonstrates that liver biopsy is essential in diagnosing unusual causes of acute liver failure, and that infiltration of the liver with NK-like T-cell lymphoma/leukemia can cause acute liver failure.

关键词： Liver failure Liver transplant Nutaral killer cell

Tooth loss patterns in older adults with special needs:a Minnesota cohort

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International Journal of Oral Science 2011年第1期3卷 27-33页

作者： Jennifer J.Clark Department of Dental Ecology University of North CarolinaChapel HillNC 27599USA

This study was conducted to detail tooth loss patterns in older adults with special needs. A total of 491 elderly subjects with special needs were retrospectively selected and followed during 10/1999-12/2006. Medical, dental, cognitive, and functional assessments were abstracted from dental records and used to predict risk of tooth loss. Tooth loss events were recorded for subjects during follow-up. Chi-squared tests were used to study the association between tooth loss and the selected risk factors. Logistic, poisson, and negative binomial regressions were developed to study tooth loss patterns. Overall, 27% of the subjects lost at least one tooth during follow-up. Fourteen subjects had tooth loss events per 100 person-years. Tooth loss pattern did not differ significantly among different special-needs subgroups （i.e. community-dwelling vs. long-term care, physically disabled vs. functionally independent）. Special-needs subjects with three or more active dental conditions at arrival had more than twice the risk of losing teeth than those without any existing conditions. After adjusting other factors, the number of carious teeth or retained roots at arrival was a significant predictor of tooth loss for older adults with special needs （P=0.001）. These findings indicate that appropriately managing active caries and associated conditions is important to prevent tooth loss for older adults with special needs.

关键词： tooth loss elderly special needs

Reinforcement as an initiator of population Jivergence and speciation

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Current Zoology 2016年第2期62卷 145-154页

作者： Karin S. PFENNIG Department of Biology University of North Carolina Chapel Hill NC 27599-3280 USA

When hybridization results in reduced fitness, natural selection is expected to favor the evolution of traits that minimize the likelihood of hybridizing in the first place. This process, termed reinforcement （or, more generally, reproductive character displacement）, thereby contributes to the evolution of enhanced reproductive isolation between hybridizing groups. By enhancing reproductive isolation in this way, reinforcement plays an important role in the final stages of speciation. However, reinforcement can also contribute to the early stages of speciation. Specifically, because selection to avoid hybridization occurs only in sympatric populations, the unfolding of reinforcement can lead to the evolution of traits in sympatric populations that reduce reproduction between conspecifics in sympatry versus those in allopatry. Thus, reinforcement between species can lead to reproductive isolation--and possibly speciation-between populations in sympatry versus those in allopatry or among different sympatric populations. Here, I describe how this process can occur, the conditions under which it is most likely to occur, and the empirical data needed to evaluate the hypothesis that reinforcement can initiate speciation.

关键词： character displacement ecological speciation gene flow hybridization population divergence reinforcement cascades reproductive isolation sexual selection speciation cascades.