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Cell Research 2001年第3期11卷 237-243页

作者： TANG WEI north carolina state university, 2900 Ligon Sf., Raleigh, NC 27607, USA north carolina state university Raleigh USA

This investigation reports a protocol for transfer and expression of foreign chimeric genes in loblolly pine (Pinus taeda L.). Transformation was achieved by co-cultivation of mature zygotic embryos with Agrobacterium tumefaciens strain LBA4404 which harbored a binary vector (pBI121) including genes for β-glucuronidase (GUS) and neomycin phosphotransferase (NPTII). Factors influencing transgene expression including seed sources of loblolly pine, concentration of bacteria, and the wounding procedures of target explants were investigated. The expression of foreign gene was confirmed by the ability of mature zygotic embryos to produce calli in the presence of kanamycin, by histochemical assays of GUS activity, by PCR analysis, and by Southern blot. The successful expression of the GUS gene in different families of loblolly pine suggests that this transformation system is probably useful for the production of the genetically modified conifers.

关键词： Pinus taeda L. Agrobacterum tumefaciens gene transfer gene expression.

Exercise immunology:Novel insights

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Journal of Sport and Health Science 2024年第3期13卷 277-279,I0001页

作者： David C.Nieman Human Performance Laboratory Appalachian State UniversityNorth Carolina Research CampusKannapolisNC 28081USA

The coronavirus disease 2019(COVID-19)pandemic heightened worldwide attention on the influence of exercise on the immune system.Questions were raised about whether regular moderate-to-vigorous physical activity(MVPA)could help prevent COVID-19 or mitigate symptoms when ill.Could MVPA bolster immunity among those most prone to COVID-19 including the elderly,obese,and immunocompromised patients?Does regular MVPA dampen systemic inflammation,thereby lessening the COVID-19 cytokine storm?

关键词： immunity inflammation thereby

Toward a fundamental understanding of the heterogeneous multiphysics behaviors of silicon monoxide/graphite composite anodes

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Carbon Energy 2024年第1期6卷 142-158页

作者： Xiang Gao Suli Li Jiachen Xue Dianyang Hu Jun Xu Department of Mechanical Engineering and Engineering Science University of North Carolina at CharlotteCharlotteNorth CarolinaUSA Vehicle Energy and Safety Laboratory(VESL) Battery ComplexityAutonomous Vehicleand Electrification(BATT CAVE)Research CenterUniversity of North Carolina at CharlotteCharlotteNorth CarolinaUSA Zhuhai CosMX Battery Co.Ltd. ZhuhaiGuangdongChina School of Data Science University of North Carolina at CharlotteCharlotteNorth CarolinaUSA

Silicon monoxide(SiO)(silicon[Si]mixed with silicon dioxide[SiO_(2)])/graphite(Gr)composite material is one of the most commercially promising anode materials for the next generation of high-energy-density lithium-ion batteries.The major bottleneck for SiO/Gr composite anode is the poor cyclability arising from the stress/strain behaviors due to the mismatch between two heterogenous materials during the lithiation/delithiation process.To date,a meticulous and quantitative understanding of the highly nonlinear coupling behaviors of such materials is still lacking.Herein,an electro–chemo–mechanics-coupled detailed model containing particle geometries is established.The underlying mechanism of the regulation between SiO and Gr components during electrochemical cycling is quantitatively revealed.We discover that increasing the SiO weight percentage(wt%)reduces the utilization efficiency of the active materials at the same 1C rate charging and enhances the hindering effects of stress-driven flux on diffusion.In addition,the mechanical constraint demonstrates a balanced effect on the overall performance of cells and the local behaviors of particles.This study provides new insights into the fundamental interactions between SiO and Gr materials and advances the investigation methodology for the design and evaluation of next-generation high-energydensity batteries.

关键词： interactions lithium-ion batteries mechanical constraint multiphysics modeling Si-based anode

Long-term olfactory loss post-COVID-19:Pathobiology and potential therapeutic strategies

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 148-155页

作者： Sarah Kim John B.Finlay Tiffany Ko Bradley J.Goldstein Department of Head and Neck Surgery&Communication Sciences Duke UniversityDurhamNorth CarolinaUSA Medical Scientist Training Program Duke UniversityDurhamNorth CarolinaUSA Department of Neurobiology Duke UniversityDurhamNorth CarolinaUSA

An acute loss of smell emerged as a striking symptom present in roughly half of the people infected with the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus in the early phases of the COVID-19 pandemic.In most COVID-19 patients,olfaction recovers over the course of a few weeks.However,a lasting partial or complete loss of smell,often associated with distorted olfactory perceptions termed parosmia,has emerged as a widespread problem impacting at least 5%-10%of those who experience anosmia due to COVID-19.Our inability to offer effective therapies to this hyposmic or anosmic population,comprising millions of patients,highlights an enormous unmet need for the medical system.Here,we summarize the current understanding of the pathobiology causing acute olfactory loss due to SARS-CoV-2 infection,focusing on how the virus interacts with the peripheral olfactory system,a major site of viral infection.We also explore the problem of long-COVID olfactory dysfunction,which may accompany other persistent systemic disorders collectively termed postacute sequelae of COVID-19.Specifically,we discuss an emerging model focused on unresolved immune cell activity driving ongoing dysfunction.Finally,we review current and future therapeutic approaches aimed at restoring olfactory function.

关键词： hyposmia inflammation long-COVID parosmia

Supplementation of vitamin E or a botanical extract as antioxidants to improve growth performance and health of growing pigs housed under thermoneutral or heat-stressed conditions

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1101-1118页

作者： Ysenia V.Silva‑Guillen Consuelo Arellano Jeffrey Wiegert R.Dean Boyd Gabriela E.Martinez Eric van Heugten Department of Animal Science North Carolina State UniversityRaleighNC 27695USA Department of Statistics North Carolina State UniversityRaleighNC 27695USA Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Animal Nutrition Research LLCAlvatonKY 42122USA.

Background Heat stress has severe negative consequences on performance and health of pigs,leading to significant economic losses.The objective of this study was to investigate the effects of supplemental vitamin E and a botanical extract in feed or drinking water on growth performance,intestinal health,and oxidative and immune status in grow-ing pigs housed under heat stress conditions.Methods Duplicate experiments were conducted,each using 64 crossbred pigs with an initial body weight of 50.7±3.8 and 43.9±3.6 kg and age of 13-week and 12-week,respectively.Pigs(n=128)were housed individually and assigned within weight blocks and sex to a 2×4 factorial arrangement consisting of 2 environments(thermo-neutral(21.2℃)or heat-stressed(30.9℃))and 4 supplementation treatments(control diet;control+100 IU/L of D-α-tocopherol in water;control+200 IU/kg of DL-α-tocopheryl-acetate in feed;or control+400 mg/kg of a botanical extract in feed).Results Heat stress for 28 d reduced(P≤0.001)final body weight,average daily gain,and average daily feed intake(-7.4 kg,-26.7%,and-25.4%,respectively)but no effects of supplementation were detected(P>0.05).Serum vitamin E increased(P<0.001)with vitamin E supplementation in water and in feed(1.64 vs.3.59 and 1.64 vs.3.24),but not for the botanical extract(1.64 vs.1.67 mg/kg)and was greater when supplemented in water vs.feed(P=0.002).Liver vitamin E increased(P<0.001)with vitamin E supplementations in water(3.9 vs.31.8)and feed(3.9 vs.18.0),but not with the botanical extract(3.9 vs.4.9 mg/kg).Serum malondialdehyde was reduced with heat stress on d 2,but increased on d 28(interaction,P<0.001),and was greater(P<0.05)for antioxidant supplementation compared to control.Cellular proliferation was reduced(P=0.037)in the jejunum under heat stress,but increased in the ileum when vitamin E was supplemented in feed and water under heat stress(interaction,P=0.04).Tumor necrosis factor-αin jejunum and ileum mucosa decreased by heat stress(P<0.05)and was reduced by vitamin E sup-plementations under heat

关键词： Botanical extract Growing pigs Heat stress Immune status Oxidative status Tocopherol Water

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Beyond cotton and polyester: An evaluation of emerging feedstocks and conversion methods for the future of fashion industry

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Journal of Bioresources and Bioproducts 2024年第2期9卷 130-159页

作者： Ryen M.Frazier Keren A.Vivas Ivana Azuaje Ramon Vera Alonzo Pifano Naycari Forfora Hasan Jameel Ericka Ford Joel J.Pawlak Richard Venditti Ronalds Gonzalez Department of Forest Biomaterials North Carolina State UniversityRaleighNC 27695USA Department of Textile Engineering Chemistry and ScienceThe Nonwovens InstituteNorth Carolina State UniversityRaleighNC 27695USA

As the global population grows,the demand for textiles is increasing rapidly.However,this puts immense pressure on manufacturers to produce more fiber.While synthetic fibers can be pro-duced cheaply,they have a negative impact on the environment.On the other hand,fibers from wool,sisal,fique,wood pulp(viscose),and man-made cellulose fibers(MMCFs)from cotton can-not alone meet the growing fiber demand without major stresses on land,water,and existing markets using these materials.With a greater emphasis on transparency and circular economy practices,there is a need to consider natural non-wood alternative sources for MMCFs to supple-ment other fiber types.However,introducing new feedstocks with different compositions may require different biomass conversion methods.Therefore,based on existing work,this review ad-dresses the technical feasibility of various alternative feedstocks for conversion to textile-grade fibers.First,alternative feedstocks are introduced,and then conventional(dissolving pulp)and emerging(fibrillated cellulose and recycled material)conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of cellulose.It is important to note that for alternative feedstocks to be adopted on a meaningful scale,high biomass availability and proximity of conversion facilities are critical factors.In north America,soybean,wheat,rice,sorghum,and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods(pre-hydrolysis kraft,acid sulfite,soda,SO2-ethanol-water,and potassium hydroxide)or by emerging cellulose fibrillation methods.While dissolving pulp conversion is well-established,fibrillated cel-lulose methods could be beneficial from cost,efficiency,and environmental perspectives.Thus,the authors strongly encourage more work in this growing research area.However,conducting thorough cost and sustainability assessments is important to determine the best feedstock a

关键词： Non-wood Residue Regenerated cellulose Dissolving pulp Man-made cellulose fiber Apparel textile

Gene silencing:Double-stranded RNA mediated mRNA degradation and gene inactivation

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Cell Research 2001年第3期11卷 181-186页

作者： TANG WEI, XIAO YAN LUO, VANESSA SANMUELS north carolina state university, Forest Biotechnology Groap, Raleigh, NC 27695, USA university of north carolina, Department of Cell and Developmental Biology, ChaPel Hill, NC 27599, USA north carolina state university Forest Biotechnology Group Raleigh USA Department of Cell and Developmental Biology University of North Carolina Chapel Hill USA

The recent development of gene transfer approaches in plants and animals has revealed that transgene can undergo silencing after integration in the genome. Host genes can also be silenced as a consequence of the presence of a homologous transgene. More and more investigations have demonstrated that double- stranded RNA can silence genes by triggering degradation of homologous RNA in the cytoplasm and by directing methylation of homologous nuclear DNA sequences. Analyses of Arabidopsis mutants and plant viral suppressors of silencing are unraveling RNA-silencing mechanisms and are assessing the role of methy- lation in transcriptional and posttranscriptional gene silencing. This review will focus on double-stranded RNA mediated mRNA degradation and gene inactivation in plants.

关键词： Gene silencing double-stranded RNA methylation homologous RNA transgene.

Otolaryngology residency program factors associated with female resident representation

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 7-11页

作者： Julia E.Canick James C.Campbell Charles R.Woodard Lars J.Grimm Alissa M.Collins Duke university School of Medicine DurhamNorth CarolinaUSA Department of Head and Neck Surgery&Communication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Department of Radiology Duke University School of MedicineDurhamNorth CarolinaUSA

Objective:Female representation in the field of otolaryngology is lacking.Residency is the first point at which medical school graduates specialize in a chosen field and thus represents an opportunity to recruit and train more female otolaryngologists.This study sought to identify program factors associated with greater female representation among resident physicians.Methods:Departmental websites of all 124 otolaryngology residency programs in the United states and Puerto Rico were examined for a list of residents.For programs with a resident roster available,the genders of residents,faculty,program directors,and chairpersons were recorded.Location and city population for each program was also recorded,as was female resident representation.Programs were compared using Pearson Chi‐squared univariate tests.Results:1,632 residents and 2,605 faculty were included in the analysis of 109 programs.The median female resident representation was 40%.Programs with larger faculty sizes,more female faculty,and urban location were associated with an above‐median female resident representation.Programs with a larger residency cohort approached significance regarding above‐median female resident representation.Higher female faculty representation,program director gender,chairperson gender,and US region were not associated with variation in female resident representation.Conclusions:Greater female otolaryngology residency representation was associated with programs having an urban location and greater numbers of female and total faculty.It was also likely that a larger resident cohort size may affect female resident representation.The proportions of female faculty,program director,and chairperson gender,as well as the US region,were not associated with variation in female resident gender representation.

关键词： gender program director recruitment residency training

Parametric “non-nested” discriminants for multiplicities of univariate polynomials

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Science China Mathematics 2024年第8期67卷 1911-1932页

作者： Hoon Hong Jing Yang Department of Mathematics North Carolina State University SMS–HCIC–School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu University

We consider the problem of complex root classification, i.e., finding the conditions on the coefficients of a univariate polynomial for all possible multiplicity structures on its complex roots. It is well known that such conditions can be written as conjunctions of several polynomial equalities and one inequality in the coefficients. Those polynomials in the coefficients are called discriminants for multiplicities. It is also known that discriminants can be obtained using repeated parametric greatest common divisors. The resulting discriminants are usually nested determinants, i.e., determinants of matrices whose entries are determinants, and so on. In this paper, we give a new type of discriminant that is not based on repeated greatest common divisors. The new discriminants are simpler in the sense that they are non-nested determinants and have smaller maximum degrees.

关键词： parametric polynomial complex roots discriminant multiplicity resultant

From non-scattering to super-scattering with Mie-tronics

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Photonics Research 2024年第4期12卷 608-624页

作者： HOOMAN BARATI SEDEH NATALIA M.LITCHINITSER Department of Electrical and Computer Engineering Duke UniversityDurhamNorth Carolina 27708USA

Electric anapoles, arising from the destructive interference of primitive and toroidal electric dipole moments, have recently emerged as a fundamental class of non-scattering sources. On the other hand, super-scattering states represent the opposite regime wherein the scattering cross-section of a subwavelength particle exceeds the single-channel limit, leading to a strong scattering behavior. Here, we demonstrate that the interplay between the topology of light and the subwavelength scatterer can lead to these two opposite responses within an isolated alldielectric meta-atom. In particular, we present the emergence of a new non-scattering state, referred to as hybrid anapole, which surpasses conventional electric dipole anapoles by achieving a remarkable 23-fold enhancement in the suppression of far-field radiation and almost threefold enhancement in the confinement of electromagnetic energy inside the meta-atom. We also explore the role of particle orientation and its inversion symmetry in the scattering response and predict the possibility of switching between non-scattering and super-scattering states within the same platform. The presented study elucidates the role of light and matter topologies in the scattering response of subwavelength meta-atoms, uncovering two opposite regimes of light-matter interaction and opening new avenues in applications such as nonlinear optics and spectroscopy.

关键词： spectroscopy opposite dipole