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Fire and retention island remnants have similar deadwood carbon stock a decade after disturbances in boreal forests of Alberta

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Forest Ecosystems 2024年第5期11卷 677-684页

作者： richard Osei Lance P.moore Rosanise A.Odell marcel Schneider Tanvir Ahmed Shovon Charles A.Nock Department of Renewable Resources University of AlbertaEdmontonCanada Institut des Sciences de La For^et Temperee Universite Du Quebec en Outaouais58 Rue PrincipaleRiponJ0V 1V0QCCanada

In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests,ecosystem-based forest management(EBm)has become the de facto management *** forestry represents one prominent way that EBm is implemented in many parts of the *** patches commonly left after harvesting serve as analogues of fire island remnants,which are patches of unburned forests in the burned forest *** the persistence of retention patches has been questioned,few studies have attempted to quantitatively compare forest attributes in both burned and harvested *** part of a larger program examining multiple aspects of ecosystem function in fire and harvest island remnants,we investigated the impact of disturbance type(fire/harvest)and forest edges on C stock in snags and coarse woody debris(CWD)found in island remnants in mixedwood boreal forests of Alberta,*** C stock(in snags and CWD)was similar between the two disturbance types and edge plots had similar total deadwood C stocks to *** edges of island remnants had about two-fold more snag C stock than their interiors in both disturbance types,but C stock in CWD was unaffected by edge effects and disturbance *** results suggest that deadwood C dynamics in island remnants in fire and harvest disturbed boreal forests were similar,thus lending support for the continued implementation of retention forestry in Alberta.

关键词： Retention forestry Deadwood Ecosystem-based management Wildfires Boreal forest

How Prime Numbers Are Interconnected and Built with Two Equations: Addition and Subtraction Rules the Function (6µ)

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Advances in Pure mathematics 2024年第4期14卷 228-241页

作者： John richard Wisdom Centre of Pedagogical Innovation (Capsule) Sorbonne University Paris France

Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , for instance 5, ), an even number divisible by 3 and 2, and Group 2 for all primes that are after ζ (such that , for instance 7), then we find a simple function: for each prime in each group, , where n is any natural number. If we start a sequence of primes with 5 for Group 1 and 7 for Group 2, we can attribute a μ value for each prime. The μ value can be attributed to every prime greater than 7. Thus for Group 1, and . Using this formula, all the primes appear for , where μ is any natural number.

关键词： Number Theory Prime Number Groups Twin Primes Prime Structure and Sequence Prime Subtraction and Addition

Preparation of Regenerated Silk Fibroin Hybrid Fibers with Hydrogen Peroxide Sensing Properties by Wet Spinning

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Journal of Renewable materials 2024年第6期12卷 1043-1055页

作者： Song Lu Jianjun Guo richard Ansah Herman Xinyi Wu Lin ma Guohua Wu College of Biotechnology Jiangsu University of Science and TechnologyZhenjiang212100China College of Agriculture Anshun UniversityAnshun561000China

Silk is widely used in the production of high-quality *** the same time,the amount of silk textiles no longer in use and discarded is increasing,resulting in significant waste and *** issue is of great concern in many countries where silk is *** peroxide as a naturally occurring compound is an important indicator of detection in both biology and the *** study aims to develop a composite fiber with hydrogen peroxide-sensing properties using discarded silk *** achieve this goal,firstly,polydopamine(PDA)was used to encapsulate the ZnFe_(2)O_(4) NPs to achieve the improvement of dispersion,and then regenerated silk fibroin(RSF)and PDA@ZnFe_(2)O_(4)/RSF hybrid fibers are prepared by wet *** has shown that PDA@ZnFe_(2)O_(4)/RSF demonstrates exceptional sensitivity,selectivity,and stability in detecting hydrogen peroxide,while maintaining high mechanical ***,the complete hybridization of PDA@ZnFe_(2)O_(4) with silk fibroin not only results in the combination of the durability of silk fibroin and PDA@ZnFe_(2)O_(4)’s rigidity,ensuring a reliable service life,but also makes PDA@ZnFe_(2)O_(4)/RSF exhibit excellent catalytic activity and ***,the composite fiber exhibits exceptional mechanical properties and reliable hydrogen peroxide sensing capabilities,making it a promising material for biological and medical applications.

关键词： Regenerated silk fibroin modified zinc ferrite nanoparticles composite fiber hydrogen peroxide sensor wet spinning

A mutation in TBXT causes congenital vertebral malformations in humans and mice

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Journal of Genetics and Genomics 2024年第4期51卷 433-442页

作者： Shuxia Chen Yunping Lei Yajun Yang Chennan Liu Lele Kuang Li Jin richard HFinnell Xueyan Yang Hongyan Wang Obstetrics and Gynecology Hospital State Key Laboratory of Genetic Engineering at School of Life SciencesKey Laboratory of Reproduction Regulation of NPFPCInstitute of Reproduction and DevelopmentFudan UniversityShanghai 200438China Shanghai Key Laboratory of metabolic Remodeling and Health Institute of Metabolism and Integrative BiologyFudan UniversityShanghai 200438China Center for Precision Environmental Health Department of Molecular and Cellular BiologyBaylor College of MedicineHoustonTX 77030USA mOE Key Laboratory of Contemporary Anthropology School of Life SciencesFudan UniversityShanghai 200438China Department of Assisted Reproduction Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China Children’s Hospital Fudan University399 Wanyuan RoadShanghai 201102China

T-box transcription factor T(TBXT;T)is required for mesodermal formation and axial skeletal *** it has been extensively studied in various model organisms,human congenital vertebral malformations(CVms)involving T are not well ***,we report a family with 15 CVm patients distributed across 4 *** affected individuals carry a heterozygous mutation,T c.596A>G(p.Q199R),which is not found in unaffected family members,indicating co-segregation of the genotype and *** vitro assays show that T p.Q199R increases the nucleocytoplasmic ratio and enhances its DNA-binding affinity,but reduces its transcriptional activity compared to the *** determine the pathogenicity of this mutation in vivo,we generated a Q199R knock-in mouse model that recapitulates the human CVm *** heterozygous Q199R mice show subtle kinked or shortened tails,while homozygous mice exhibit tail filaments and severe vertebral ***,we show that the Q199R mutation in T causes CVm in humans and mice,providing previously unreported evidence supporting the function of T in the genetic etiology of human CVm.

关键词： Congenital vertebral malformation TBXT T gene Loss-of-function mutation

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 97-104页

作者： mihai A.Bentan Evan R.Reiter richard m.Costanzo Daniel H.Coelho Department of Otolaryngology-Head&Neck Surgery Virginia Commonwealth University School of MedicineRichmondVirginiaUSA

Objective:The aim of this study was to review findings from a large prospective national database of chemosensory disturbances associated with coronavirus disease 2019(COVID-19)*** Sources:The Virginia Commonwealth University Smell and Taste Center national database of COVID-19 chemosensory ***:A series of online surveys,first opened on April 10,2020,was made accessible nationwide to any adult with sudden chemosensory dysfunction since January *** received subsequent follow-up surveys 14 days,1 month,3 months,and 6 months after *** additional survey was sent to all participants on may 28,2022 to assess long-term *** pertaining to demographics,symptoms,comorbidities,treatments,and life impact was ***:Of 363 participants who reported complete smell recovery,51.2%recovered within 1 month,70%within 3 months,and 79%within 6 months,while 8.8%took over 1 year to completely *** all participants,7.5%had no smell *** predictors of recovery included agemale gender,and the presence of nasal *** predictors included difficulty breathing and prior head *** participants reported a decrease in quality of life and the presence of potential safety hazards associated with decreased smell ***:most subjects with COVID-19-related chemosensory dysfunction recover,with the majority noting complete recovery within weeks of *** aged over 40 years and female gender were associated with lower rates of recovery.A considerable number of participants reported significant impact on quality of life and safety.

关键词： anosmia COVID-19 smell

Superdirective Circular Arrays of Electric and Huygens Dipole Elements

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Electromagnetic Science 2024年第1期2卷 38-62页

作者： richard W.Ziokowski TheUniversityofArizona TucsonAZ85721USA

Uniform circular arrays(UCAs)provide both omnidirectional(360°)and directive(sector)coverage of the azimuthal *** versions with unidirectional,high front-to-back ratio(FTBR)properties could provide the radiated field char-acteristics being pursued for NextG wireless networks and their perceived *** UCA configurations–full,semi-circular,and sector–that radiate vertically-polarized(VP)fields and are composed of either omnidirectional electric dipole ele-ments or unidirectional Huygens dipole elements are analyzed first with conventional methods as reference *** omni-and uni-directional element configurations are then treated with several optimization techniques:the classic Rayleigh-quotient(RQ)method and its unidirectional-constrained version;the eigenbeam decomposition and synthesis(EBDS)technique used to design su-perdirective acoustic receiving arrays;and the Bessel-azimuthal multipole(BEAm)approach developed *** arrays are identified as being superdirective with extremely high FTBR *** performance characteristics of the arrays of unidirectional elements are demonstrated to be superior in ***,it is shown that larger radius arrays with RQ-specified excitation amplitudes are robust to changes in them whereas the outcomes of the corresponding small radius versions are *** the other hand,the BEAm-optimized densely-packed small-radius superdirective arrays are quite tolerant to those variations while generating unidirectional pseudo-needle beams.

关键词： Directivity Huygens dipole antennas multipoles Needle radiation Optimization Superdirective arrays Uniform circular arrays.

Framework to model User Request Access Patterns in the World Wide Web

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Journal of Software Engineering and Applications 2024年第2期17卷 69-88页

作者： richard Hurley Robert Sturgeon Department of Computer Science Trent University Peterborough ON Canada

In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pages. Our framework model consists of three sub-models: one for user file access, one for web pages, and one for storage servers. Web pages are assumed to consist of different types and sizes of objects, which are characterized using several categories: articles, media, and mosaics. The model is implemented with a discrete event simulation and then used to investigate the performance of our system over a variety of parameters in our model. Our performance measure of choice is mean response time and by varying the composition of web pages through our categories, we find that our framework model is able to capture a wide range of conditions that serve as a basis for generating a variety of user request patterns. In addition, we are able to establish a set of parameters that can be used as base cases. One of the goals of this research is for the framework model to be general enough that the parameters can be varied such that it can serve as input for investigating other distributed applications that require the generation of user request access patterns.

关键词： Performance modelling World Wide Web Simulation User Request Access Patterns Framework

Are there sex-based disparities in cataract surgery?

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： matthew D.Geiger Anne m.Lynch Alan G.Palestine Nathan C.Grove Karen L.Christopher richard S.Davidson michael J.Taravella Naresh mandava Jennifer L.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIm:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan mountains

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Plant Diversity 2024年第3期46卷 321-332页

作者： Jieshi Tang Xiaoyan Fan richard I.milne Heng Yang Wenjing Tao Xinran Zhang mengyun Guo Jialiang Li Kangshan mao Key Laboratory of Bio-Resource and Eco-Environment of ministry of Education College of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610065PR China Institute of molecular Plant Sciences University of EdinburghEdinburgh EH93JHUK School of Ecology and Environment Tibet UniversityLhasa 850000PR China

Biogeographical barriers to gene flow are central to plant *** East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across *** we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern *** and migration hypotheses were tested using coalescent-based *** historical gene flow was observed between the western and eastern groups of ***,but substantial flow occurred across both the mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central ***-borne pollen and seeds may have facilitated the dispersal of *** following prevalent northwest winds in the *** also found that the Hengduan mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of *** niche modeling suggested that *** has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 *** phylogeographic pattern of *** reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate *** study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas.

关键词： Chloroplast DNA microsatellite Phylogeographic break Populus rotundifolia Quaternary history Wind direction