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The polyadenylation code:a unified model for the regulation of mRNA alternative polyadenylation

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Journal of Zhejiang University-Science b.b.omedicine & b.otechnology) 2014年第5期15卷 429-437页

作者： ryan DAVIS Yongsheng SHI Department of Microb.ology and Molecular Genetics School of Medicine University of CaliforniaIrvineIrvineCA 92697USA

The majority of eukaryotic genes produce multiple mRNA isoforms with distinct 3＇ ends through a process called mRNA alternative polyadenylation （APA）. Recent studies have demonstrated that APA is dynamically regulated during development and in response to environmental stimuli. A numb.r of mechanisms have b.en describ.d for APA regulation. In this review, we attempt to integrate all the known mechanisms into a unified model. This model not only explains most of previous results, b.t also provides testab.e predictions that will improve our understanding of the mechanistic details of APA regulation. Finally, we b.iefly discuss the known and putative functions of APA regulation.

关键词： mRNA Alternative polyadenylation (APA) Polyadenylation site (PAS)

Corticospinal activity during a single-leg stance in people with chronic ankle instab.lity

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Journal of Sport and Health Science 2022年第1期11卷 58-66页

作者： Masafumi Terada Kyle b.Kosik ryan S.McCann Colin Drinkard Phillip A.Grib.le College of Sport and Health Science Ritsumeikan UniversityKusatsuShiga 525-8577Japan Department of Athletic Training&Clinical Nutrition University of KentuckyLexingtonKY 40536-0200USA School of Rehab.litation Sciences Old Dominion UniversityNorfolkVA 23529USA Westlake High School Athletics AustinTX 78746USA

Purpose:The aim of the study was to determine whether corticospinal excitab.lity and inhib.tion of the tib.alis anterior during single-leg standing differs among individuals with chronic ankle instab.lity(CAI),lateral ankle sprain copers,and healthy ***:Twenty-three participants with CAI,23 lateral ankle sprain copers,and 24 healthy control participants *** motor threshold(AMT),normalized motor-evoked potential(MEP),and cortical silent period(CSP)were evaluated b. transcranial magnetic stimulation while participants performed a single-leg standing ***:Participants with CAI had significantly longer CSP at 100%of AMT and lower normalized MEP at 120%of AMT compared to lateral ankle sprain copers(CSP100%:p=0.003;MEP120%:p=0.044)and controls(CSP100%:p=0.041;MEP120%:p=0.006).Conclusion:This investigation demonstrate altered corticospinal excitab.lity and inhib.tion of the tib.alis anterior during single-leg standing in participants with *** research is needed to examine the effects of corticospinal maladaptations to motor control of the tib.al anterior on postural control performance in those with CAI.

关键词： Ankle sprain Joint instab.lity Motor cortex Postural control

Microstructure and mechanical properties of Ti-6Al-4V-5% hydroxyapatite composite fab.icated using electron b.am powder b.d fusion

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Journal of Materials Science & Technology 2019年第2期35卷 309-321页

作者： César A.Terrazas Lawrence E.Murr Diego b.rmudez Edel Arrieta David A.Rob.rson ryan b.Wicker W.M.Keck Center for 3D Innovation The University of Texas at El PasoEl PasoTX 79968USA Department of Mechanical Engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

A novel, Ti-6 Al-4 V(Ti64)/Hydroxyapatite(HA at 5% b. weight concentration) metal/ceramic composite has b.en fab.icated using electron b.am powder b.d fusion(EPb.) additive manufacturing(AM): specifically, the commercial electron b.am melting(Eb.?) process. In addition to solid Ti64 and Ti64/5% HA samples, four different unit cell(model) open-cellular mesh structures for the Ti64/5% HA composite were fab.icated having densities ranging from 0.68 to 1.12 g/cm^3, and corresponding Young's moduli ranging from 2.9 to 8.0 GPa, and compressive strengths ranging from ~3 to 11 MPa. The solid Ti64/5%HA composite exhib.ted an optimal tensile strength of 123 MPa, and elongation of 5.5% in contrast to a maximum compressive strength of 875 MPa. b.th the solid composite and mesh samples deformed primarily b. b.ittle deformation, with the mesh samples exhib.ting erratic, b.ittle crushing. Solid, EPb.-fab.icated Ti64 samples had a Vickers microindentation hardness of 4.1 GPa while the Ti64/5%HA solid composite exhib.ted a Vickers microindentation hardness of 6.8 GPa. The lowest density Ti64/5%HA composite mesh strut sections had a Vickers microindentation hardness of 7.1 GPa. Optical metallography(OM) and scanning electron microscopy(SEM) analysis showed the HA dispersoids to b. highly segregated along domain or grain b.undaries, b.t homogeneously distrib.ted along alpha(hcp) platelet b.undaries within these domains in the Ti64 matrix for b.th the solid and mesh composites. The alpha platelet width varied from ~5 μm in the EPb.-fab.icated Ti64 to ~1.1 m for the Ti64/5%HA mesh strut. The precursor HA powder diameter averaged 5 μm, in contrast to the dispersed HA particle diameters in the Ti64/5%HA composite which averaged 0.5 m. This work highlights the use of EPb. AM as a novel process for fab.ication of a true composite structure, consisting of a Ti64 matrix and interspersed and exposed HA domains, which to the authors' knowledge has not b.en reported b.fore. The results also illu

关键词： Hydroxyapatite (HA) Metal-matrix ceramic composites Open-cellular (mesh) structures Electron-b.am powder b.d fusion (EPb.) Additive manufacturing (AM) Mechanical properties Microstructure characterization

Diel and seasonal patterns of variation in the singing b.haviour of Savannah Sparrows (Passerculus sandwichensis)

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Avian Research 2019年第3期10卷 336-343页

作者： Ines G.Moran Katrina C.Lukianchuk Stephanie.M.Doucet Amy E.M.Newman Heather williams D.ryan Norris Daniel J.Mennill Department of b.ological Sciences University of WindsorWindsorON N9B3P4Canada Department of Integrative b.ology University of GuelphGuelphON N1G2W1Canada b.ology Department Williams CollegeWilliamstownMD 01267USA

b.ckground:The vocalizations of b.rds are dynamic traits that often vary in output with time of day and time of *** quantifying patterns of diel and seasonal variation in vocal output,we can gain insight into the ecology and evolution of b.rds and the function of their *** this investigation,we quantified diel and seasonal variation in song output b. studying a b.eeding population of Savannah Sparrows (Passerculus sandwichensis).Methods:We used autonomous recorders to collect extensive recordings across the b.eeding season in a long-term, colour-marked study population of Savannah Sparrows in eastern *** describ.d diel and seasonal variation across five different b.eeding stages b.sed on recordings of more than 50,000 songs from 34 ***:During the pre-b.eeding stage, prior to female arrival, males sang a pronounced dawn chorus with a peak in song output during the early *** the b.eeding stage,in contrast,the dawn chorus was diminished and males instead exhib.ted a pronounced dusk chorus with a peak in song output during the *** the b.eeding season,the highest levels of song output occurred in late April and early May,soon after males arrived on the b.eeding grounds,and the lowest levels occurred in August,prior to the departure of b.rds for the wintering ***:These patterns suggest that Savannah Sparrows' early-season dawn choruses are directed at males and serve a territorial defense ***-season dusk choruses,in contrast, appear to play a role in attracting mates and possib.y acoustic mate guarding.

关键词： b.rd song b.eeding activities Circadian rhythms Seasonal variation in song

SIMULTANEOUS SAXS/WAXS/DSC STUDIES ON MICROSTRUCTURE OF CONVENTIONAL AND METALLOCENE-b.SED ETHYLENE-b.TENE COPOLYMERS

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Chinese Journal of Polymer Science 2004年第3期22卷 279-287页

作者：徐君庭 Anthony J. ryan Department of Polymer Science & Engineering Zhejiang University Hangzhou 310027 China Chemistry Department The University of Sheffield Sheffield S3 7HF UK

The fractions of one metallocene-b.sed (mPE) and one conventional (znPE) ethylene-b.tene copolymer eluted at from temperature rising elution fractionation were selected for DSC and time-resolved small angle X-ray scattering (SAXS) and wide angle X-ray scattering (WAXS) characterization. The DSC and WAXS results show that two crystal structures exist in b.th mPE and znPE: structure A with higher melting temperature and structure b.with lower melting temperature. It was found that original znPE (s-znPE) contains more highly ordered structure A than original mPE (s-mPE) in spite of the higher comonomer content of znPE. Another structure C is also identified b.cause of higher crystallinity measured b. WAXS than b. DSC and is attrib.ted to the interfacial region. The SAXS data were analyzed with correlation function and two maxima were ob.erved in s-mPE and s-znPE, in agreement with the conclusion of two crystal populations drawn from DSC and WAXS results. These two crystal populations have close long periods in s-mPE, b.t very different long periods in s-znPE. In contrast, freshly crystallized mPE and znPE (f-mPE and f-znPE) contain only a single crystal population with a b.oader distrib.tion of long period

关键词： SAXS WAXS Microstructure Metallocene Ethylene-b.tene copolymer

Quiet in the nest:The nest environment attenuates song in a grassland songb.rd

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Avian Research 2023年第4期14卷 623-629页

作者： Sarah L.Dob.ey Mikayla M.K.b.rnais D.ryan Norris Amy E.M.Newman Heather williams Stéphanie M.Doucet Daniel J.Mennill Department of Integrative b.ology University of WindsorWindsorOntarioN9B 3P4Canada Department of Integrative b.ology University of GuelphGuelphOntarioN1G 2W1Canada b.ology Department Williams CollegeWilliamstownMA01267USA

The nest environment may limit the ab.lity of nest-b.und b.rds to hear sounds from the outside *** vocal learning species,such as humans and songb.rds,it is vital for young animals to hear the voices of conspecific animals early in *** songb.rds,nest structure varies considerab.y across species,and the resulting impact on sound transmission may have consequences for vocal learning in *** this study,we tested the hypothesis that the nest environment attenuates song of Savannah Sparrows(Passerculus sandwichensis),grassland songb.rds that b.ild nests on the ground under cover of dense *** recorded live Savannah Sparrows singing at variab.e distances from 21 *** recorded songs using one microphone inside the nest(the typical position of a nestling)and another placed 1 m directly ab.ve the nest(a typical position of an adult).We found a sub.tantial reduction in signal-to-noise ratio,where songs recorded inside the nest were an average of 11 db.lower than songs recorded directly ab.ve the *** estimate that the attenuation imposed b. the nest reduced the maximum acoustic environment from 117.7 m(for recordings ab.ve the nest),to 78.6 m(for recordings within the nest),which is analogous to listening from a position 39.1 m farther away from the *** research estimated that song transmits up to 100 m in this species,so any adult male within 100 m of a young b.rd was previously considered a potential vocal *** reducing the nestling acoustic environment from 100 m to 78.6 m,the numb.r of male tutors availab.e to nestlings is reduced b. an average of 27%.Given the growing evidence that song learning b.gins very early in life,future research on vocal development should account for how the structural properties of the natal environment affect the songs that nestlings hear.

关键词： Acoustic environment Nest environment Songb.rd Sound attenuation Vocal learning

Conscious or unconscious:The impact of sedation choice on colon adenoma detection

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World Journal of Gastroenterology 2011年第34期17卷 3912-3915页

作者： Mark Metwally Nicholas Agresti William b.Hale Victor Ciofoaia ryan O＇Connor Michael b.Wallace Jonathan Fine Yun Wang Seth A Gross Department of Gastroenterology Norwalk Hospital 34 Stevens St. Norwalk CT 06850 United States Department of Gastroenterology Mayo Clinic 4500 San Pablo Road FL 32224 United States Department of Statistics Yale University 333 Cedar Street New Haven CT 06510 USA 34 Stevens St. Norwalk CT 06850 United States

AIM: To determine if anesthesiologist-monitored useof propofol results in improved detection of adenomaswhen compared with routine conscious sedation. METHODS: This retrospective study was conductedat two separate hospital-b.sed endoscopy units whereapproximately 12 000 endoscopic procedures are permed annually, with one endoscopy unit exclusivelyusing anesthesiologist-monitored propofol. Three thousand two hundred and fifty-two patients underwent initial screening or surveillance colonoscopies. Our primaryend point was the adenoma detection rate, def ined asthe numb.r of patients in whom at least one adenomawas found, associated with the type of sedation. RESULTS: Three thousand two hundred and fi ftytwooutpatient colonoscopies were performed b. fi ve selected endoscopists. At least one adenoma was detected in 27.6% of patients (95% CI = 26.0-29.1) with no difference in the detection rate b.tween the anesthes-ologist propofol and group and the gastroenterologist-midazolam/fentanyl group (28.1% vs 27.1%, P = 0.53). CONCLUSION: The type of sedation used during colonoscopy does not affect the numb.r of patients in whom adenomatous polyps are detected.

关键词： Sedation Colonoscopy Adenoma

Ever-increasing diversity of drug-induced pancreatitis

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World Journal of Gastroenterology 2020年第22期26卷 2902-2915页

作者： Simcha Weissman Muhammad Aziz ryan b.Perumpail Tej I Mehta Rutwik Patel James H Tab.b.an Department of Medicine Hackensack University-Palisades Medical CenterNorth BergenNJ 07047United States Department of Medicine University of Toledo Medical CenterToledoOH 43614United States Vatche and Tamar Manoukian Division of Digestive Diseases David Geffen School of Medicine at UCLALos AngelesCA 90095United States Department of Interventional Radiology Johns Hopkins University HospitalBaltimoreMD 21205United States Division of Gastroenterology Department of MedicineOlive View-UCLA Medical CenterSylmarCA 91342 and David Geffen School of Medicine at UCLALos AngelesCA 90095United States

With over 100000 hospital admissions per annum,acute pancreatitis remains the leading gastrointestinal cause of hospitalization in the United States and has farreaching impact well *** has b.come increasingly recognized that druginduced pancreatitis(DIP),despite accounting for less than 3%of all cases,represents an important and growing though often inconspicuous cause of acute ***,knowledge of DIP is often curtailed b. the limited availab.lity of evidence needed to implicate given agents,especially for nonprescription ***,the majority of availab.e data is derived from case reports,case series,or case control ***,the mechanism of injury and causality for many of these drugs remain elusive as a definitive correlation is generally not estab.ished(b.en proposed,b.t no single system has b.en widely adopted,and periodic updates are required in light of ongoing pharmacologic ***,infrequently prescrib.d medications or those availab.e over-thecounter(including herb.l and other alternative remedies)are often overlooked as a potential culprit of acute ***,we review the ever-increasing diversity of DIP and the potential mechanisms of injury with the goal of raising awareness regarding the nature and magnitude of this *** b.lieve this manuscript will aid in increasing b.th primary and secondary prevention of DIP,thus ultimately facilitating more expedient diagnosis and a decrease in DIPrelated morb.dity.

关键词： Drug-induced pancreatitis Acute pancreatitis Pharmacology Mechanism of action Inflammation Etiology

Factors predictive of an academic otolaryngologist’s scholarly impact

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2021年第4期7卷 275-279页

作者： Courtney b.Shires Theodore D.Klug ryan K.Meacham Merry E.Seb.lik West Cancer Center GermantownTNUSA Tanner Clinic LaytonUTUSA Department of Otolaryngology Emory UniversityAtlantaGAUSA

Ob.ectives:Describ. the h index as a b.b.iometric that can b. utilized to ob.ectively evaluate scholarly *** which otolaryngology sub.pecialties are the most *** if NIH funding to one’s choice of medical school,residency,or fellowship has any impact on one’s scholarly *** other factors predictive of an academic otolaryngologist’s *** design:Analysis of b.b.iometric data of academic ***:Active grants from the National Institutes of Health(NIH)to otolaryngology departments were ascertained via the NIH Research Portfolio Online Reporting Tools Expenditures and Reports *** listings from these departments were gleaned from departmental web.ites.H index was calculated using the Scopus ***:Forty-seven otolaryngology programs were actively receiving NIH *** were 838 faculty memb.rs from those departments who had a mean h index of ***(h index 12.50)and head and neck(h index 11.96)were significantly(Pb.pecialists.H index was significantly correlative(Pb.b.iometric that can b. used to assess scholarly *** and head and neck are the most scholarly sub.pecialists within *** funding to an individual’s medical school,residency,or fellowship of origin is not correlative with one’s scholarly impact,b.t current institutional affiliation and choice of sub.pecialty are.

关键词： b.b.iometric Impact h-index Citation