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SYMMETRIC SIGN PATTERN MATRICES THAT REQUIRE UNIQUE INERTIA

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Numerical Mathematics A journal of Chinese Universities(English Series) 2000年第S1期9卷 12-14页

作者： Hall frank j. Department of Mathematics and Statistics Georgia State University Atlanta

In qualitative and combinatorial matrix theory,we study properties of a matrix basedon qualitative information,such as the signs of entries in the matrix.A matrix whose en-tries are from the set{+,-,0}is called a sign pattern matrix (or sign pattern).For a re-al matrix B,by sgn (B) we mean the sign pattern matrix in which each positive (respec-tively,negative,zero) entry of B is replaced by+(respectively,-,0).If A is an

关键词： cycle In length SYMMETRIC SIGN PATTERN MATRICES THAT REQUIRE UNIQUE INERTIA SMR

Survival of boll weevil （Coleoptera： Curculionidae） adults after feeding on pollens from various sources

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Insect Science 2007年第6期14卷 503-510页

作者： SHOIL M. GREENBERG GRETCHEN D. jONES frank EISCHEN RANDY j. COLEMAN jOHN j. ADAMCZYK, jR. TONG-XIAN LIU MAMOUDOU SETAMOU USDA-ARS KSARC-BIRU Weslaco USDA-ARS APMRU College Station USDA-ARS KSARC-Honey Bee Research Unit Department of Entomology Texas AgriLife Research Texas A&M University System Texas A&M University Kingsville Citrus Center Weslaco Texas USA

The survival of overwintering boll weevil, Anthonomus grandis grandis （Boheman）, adults on non-cotton hosts in the Lower Rio Grande Valley （LRGV） of Texas was examined from 2001 to 2006. The success of the Boll Weevil Eradication Program, which was reintroduced into the LRGV in 2005, depends on controlling overwintering boll weevil populations. Laboratory studies were conducted using boll weevil adults that were captured in pheromone traps from September through March. The number of adults captured per trap declined significantly in the field from fall to the beginning of spring （3.5-7.0-fold）. The proportion of trapped males and females did not differ significantly. The mean weight of boll weevil adults captured in September was 13.3 mg, while those of captured adults from November to February were significantly lower and ranged from 6.7 to 7.8 mg. Our results show that boll weevil adults can feed on different plant pollens. The highest longevity occurred when adults were fed almond pollen or mixed pollens （72.6 days and 69.2 days, respectively） and the lowest when they fed on citrus pollen or a non-food source （9.7 days or 7.4 days, respectively）. The highest adult survival occurred on almond and mixed pollens [88.0%-97. 6% after 1st feeding period （10 days）, 78.0%-90.8% after 3rd feeding period （10 days）, 55. 0%-83.6% after 5th feeding period （10 days）, and 15.2%-32.4% after lOth feeding period （10 days）]. The lowest adult survival occurred on citrus pollen [52.0%-56.0% after 1st feeding period （10 days）, 13.3% after 3rd and 5th feeding periods （10 days）, and 0 after 6th feeding period （10 days）]. Pollen feeding is not a behavior restricted to adult boll weevils of a specific sex or physiological state. Understanding how boll weevil adults survive in the absence of cotton is important to ensure ultimate success of eradicating this pest in the subtropics.

关键词： boll weevil Anthonomus grandis grandis Curculionidae subtropics pollen

Efficiency, Effectiveness:Knowledge Exchange within Modernising Asia

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博鳌观察 2016年第4期 36-38,7页

作者： frank-jürgen Richter Horasis

It is vital to promote the top down discussionsthrough forums like those of Boao and *** their participation government ministers,CEOs, and so on will better identify with top-levelbroad issues and will be able to ins... 详细信息

关键词： Effectiveness Efficiency will

Disagreement in middle ear volume estimation between tympanometry and three-dimensional volume reconstruction in the context of tympanic membrane perforation

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journal of Otology 2017年第2期12卷 74-79页

作者： David j.Carpenter Debara L.Tucci David M.Kaylie Dennis O.frank-Ito Division of Head and Neck Surgery&Communication Sciences Department of SurgeryDuke University Medical CenterDurhamNCUSA Computational Biology&Bioinformatics PhD Program Duke UniversityDurhamNCUSA Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNCUSA

Introduction: Middle ear volume(MEV) is a clinically relevant parameter across middle ear diseases. MEV values between these techniques have never before been tested for agreement in ears with perforated tympanic membranes(TMs).Methods: Middle ears were identified from 36 patients ranging 18-89 years of age with TM perforations who underwent tympanometry and temporal bone computed tomography(CT) between 2005 and 2015. MEVs calculated by both tympanometry and three-dimensional volume reconstruction(3DVR) were analyzed for agreement using Bland Altman plots. The differences between tympanometric and 3DVR MEV values for each given middle ear were characterized across MEV quartiles(1= smallest; 4= largest) and across increasing states of middle ear disease using Kruskale Wallis and Wilcoxon testing with Bonferroni ***: Bland Altman plots demonstrated significant disagreement between MEV measurement techniques. Differences between tympanometric(T) and 3DVR MEV values were significantly greater with increasing average(i.e.(Tt3DVR)/2)) MEV per linear regression(p < 0.0001). Significance was demonstrated between fourth and first average MEV quartiles(p= 0.0024), fourth and second quartiles(p= 0.0024), third and first quartiles(p= 0.0048), and third and second quartiles(p= 0.048). Absolute MEV difference was not significantly different across varying states of middle ear disease(p= 0.44).Conclusion: Statistically and clinically significant disagreement was demonstrated between tympanometric and 3DVR MEV values. Studies that vary in MEV estimation techniques may be expected to demonstrate significantly different results. These preliminary results suggest that clinicians should endeavor to seek further confirmation when interpreting high tympanometric MEV values.

关键词： Middle ear volume Tympanometry Three-dimensional volume reconstruction Tympanic membrane perforation

The anatomic determinants of conductive hearing loss secondary to tympanic membrane perforation

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journal of Otology 2017年第3期12卷 125-131页

作者： David j.Carpenter Debara L.Tucci David M.Kaylie Dennis O.frank-Ito Division of Head and Neck Surgery & Communication Sciences Department of Surgery Duke University Medical Center Durham NC USA Computational Biology & Bioinformatics PhD Program Duke University Durham NC USA Department of Mechanical Engineering and Materials Science Duke University Durham NC USA

Objectives: Recent studies have introduced middle ear volume(MEV) as a novel determinant of perforation-induced conductive hearing loss(CHL) in a mechanism driven by trans-tympanic membrane pressure differences. The primary aims of this preliminary report are to: 1) correlate CHL with perforation size; 2) describe the relationship between CHL and MEV; and 3) compare CHL across a range of cholesteatoma ***: A retrospective pilot study was performed in 31 subjects with audiometry indicative of conductive hearing loss, temporal bone CT scans,and no prior middle ear surgery. Perforation size and MEV were analyzed with respect to CHL in a cohort of 10 perforated ears with no cholesteatoma. CHLs were compared in 3 groups defined by extent of cholesteatoma ***: Ears with large and small perforations showed mean ABG values of 32.0 ± 15.7 dB and 16.0 ± 16.4 dB, respectively. A direct relationship was observed between MEV and CHL for ears with large perforations across all frequencies, whereas this relationship for small perforations was frequency-dependent. Finally, a statistically significant increase in CHL was found across ears with increasing cholesteatoma involvement at 1000 Hz(X^2(2) = 9.786, p = 0.008),2000 Hz(x^2(2) = 8.455, p = 0.015),and 4000 Hz(x^2(2)= 8.253, p = 0.016).Conclusions: These pilot data suggest that greater perforation-induced conductive hearing losses may be associated with larger perforation sizes and cholesteatoma. The correlation between MEV and CHL may require additional study.

关键词： Perforation-induced hearing loss Conductive hearing loss Middle ear volume Three-dimensional volume reconstruction

Existence of 4-fold Perfect (v, {5, 8}, 1)-Mendelsohn Designs

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Acta Mathematica Sinica,English Series 2010年第3期26卷 445-464页

作者： Ming Xiao XIANG Yun Qing XU frank E. BENNETT Department of Mathematics Ningbo University Ningbo 315211 P. R. China Department of Mathematics Mount Saint Vincent University Halifax Nova Scotia B3M 2J6 Canada

Let v be a positive integer and let K be a set of positive integers. A （v, K, 1）-Mendelsohn design, which we denote briefly by （v, K, 1）-MD, is a pair （X, B） where X is a v-set （of points） and B is a collection of cyclically ordered subsets of X （called blocks） with sizes in the set K such that every ordered pair of points of X are consecutive in exactly one block of B. If for all t =1, 2,..., r, every ordered pair of points of X are t-apart in exactly one block of B, then the （v, K, 1）-MD is called an r-fold perfect design and denoted briefly by an r-fold perfect （v, K, 1）-MD. If K = {k） and r = k - 1, then an r-fold perfect （v, （k）, 1）-MD is essentially the more familiar （v, k, 1）-perfect Mendelsohn design, which is briefly denoted by （v, k, 1）-PMD. In this paper, we investigate the existence of 4-fold perfect （v, （5, 8}, 1）-Mendelsohn designs.

关键词： Mendelsohn design transversal design group divisible desiga

DICER-LIKE3 Activity in Physcomitrella patens DICER-LIKE4 Mutants Causes Severe Developmental Dysfunction and Sterility

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Molecular Plant 2012年第6期5卷 1281-1294页

作者： M. Asif Arif Isam Fattash Zhaorong Ma Sung Hyun Cho Anna K. Beike Ralf Reski Michael j. Axtell Wolfgang frank Plant Biotechnology Faculty of Biology University of Freiburg Schaenzlestral3e 1 D-79104 Freiburg Germany Department of Biology Pennsylvania State University University Park PA 16802 USA FRISYs Freiburg Initiative for Systems Biology D-79104 Freiburg: Germany BIOSS Centre for Biological Signalling Studies D-79104 Freiburg Germany FRIAS Freiburg Institute for Advanced Studies D-79104 Freiburg Germany

Trans-acting small interfering RNAs （ta-siRNAs） are plant-specific siRNAs released from TAS precursor tran- scripts after microRNA-dependent cleavage, conversion into double-stranded RNA, and Dicer-dependent phased process- ing. Like microRNAs （miRNAs）, ta-siRNAs direct site-specific cleavage of target RNAs at sites of extensive complementarity. Here, we show that the DICER-LIKE 4 protein of Physcomitrella patens （PpDCL4） is essential for the biogenesis of 21 nucleotide （nt） ta-siRNAs. In APpDCL4 mutants, off-sized 23 and 24-nt ta-siRNAs accumulated as the result of PpDCL3 activity. APpDCL4 mutants display severe abnormalities throughout Physcomitrella development, including sterility, that were fully reversed in APpDCL3/APpDCL4 double-mutant plants. Therefore, PpDCL3 activity, not loss of PpDCL4 function per se, is the cause of the APpDCL4 phenotypes. Additionally, we describe several new Physcomitrella trans-acting siRNA loci, three of which belong to a new family, TA56. TAS6 loci are typified by sliced miR156 and miR529 target sites and are in close proximity to PpTAS3 loci.

关键词： ta-siRNA miR156 PpDCL3 PpDCL4 development moss.

An Assessment on the Performance of Real-Time Routing Protocols for Wireless Sensor Network

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An Assessment on the Performance of Real-Time Routing Protoc...

作者： Obeng frank 湖南大学

学位级别：硕士

由于在无线传感器网络中的实时应用最主要关注的问题是可靠、及时的数据交付,所以近期使用的无线传感器网络(WSN)的实时应用引起对路由协议的重点研究。实时路由必须找到一条从源到目的地,大多数通常满足时间约束的路径。出于这个原因,... 详细信息

由于在无线传感器网络中的实时应用最主要关注的问题是可靠、及时的数据交付,所以近期使用的无线传感器网络(WSN)的实时应用引起对路由协议的重点研究。实时路由必须找到一条从源到目的地,大多数通常满足时间约束的路径。出于这个原因,提出一个能够延长网络生存期的算法是有必要的。本文提出了一个新颖的实时路由算法,在控制系统中引入了“等待时间”以确保和延长网络的生存期。引入术语控制系统,是因为它有顾及到实时受限系统诸如它是如何稳定扰动和如何快速达到所期望的行为,并且在如何消除昂贵的布线方面也有优势。本研究进一步提出了对现有的无线传感器网络实时路由协议的评价和评估方法,并强调了它们的性能、优缺点及今后的研究中面临的各种挑战。现代传感器网络用于处理真实环境的事务,通信满足实时约束往往是非常必要的。到目前为止,适合于自组织传感器网络的充分满足实时要求的成果几乎没有。在无线传感器网络中提出一个合适的路由协议是非常重要的,因为它直接影响到应用的性能。更具体地说,无线传感器网络和无线网络控制系统中的路由协议应该满足特定的性能标准。由于无线网络控制系统的文献中缺乏相关合适的路由协议,促进了本文提出一种最新的用于无线网络控制系统应用的路由协议。本文提出了一个适用于大规模网络的基于反馈控制和无状态算法的能提供实时保证的协议。本文评价实时性的仿真工具为ISIS公司开发的的一个java工具-j prowler,它是一个验证和分析自组织网络协议的开源事件仿真器。能量有效性是无线传感器网络近期很多研究的主要目标。在实时协议中,最好的节能方法就是将一些节点转为休眠状态,使其以较低的占空比运行。不过这应该不会引起无线传感器网络性能的下降,例如失去连通性。重点放在算法的实现,在密集无线传感器网络中,该算法允许出现不连通和延长网络的等待时间,提高网络的性能,从而确保有效的生存期。具体来说,,考虑一个射手本地化定位的应用,传感器节点被撒播在一个区域中,用于监视该区域感兴趣的事件。当这样的事件发生时,传感器节点产生数据,并将它们路由至网关。为了能够这样做,此时必须存在一条到达网关的由多个活跃节点构成的路径。如果没有这样的路径存在,节点必须等待一段时间,直到这个路径变为有效。网关为了获得这些数据包,将产生一定的延时。出于这个原因,确保网络处于总是处于连通状态是很重要的。问题是要找到节点的多个分离的子集,这些节点为了确保连通性而处于唤醒状态。通过使用多个子集,我们可以在这些被唤醒的子集中进行切换从而延长网络生存期一一这期间应用程序将成功完成其目标。例如,我们如果有两个子集,与只有一个子集相比,我们可以将两个网络的生存期相乘。在找到这些集合之后,我们必须使每个分离子集内的节点同步,使得它们同一时间处于唤醒状态,从而达到确保路由的目的。子集交替处于休眠和唤醒的阶段中,单一子集在给定的时间处于唤醒状态。由于这些子集中的节点是不相交的,从而保证了网络的能量平衡。本文提出了一个基于概率的算法,因此并不需要保证所有节点处于连通状态,但是需要所给定数目节点保持连通的概率,达到减少占空比的目的。算法起先执行并没有延长等待时间,然而具有较短等待时间的节点在连通性方面的效果不佳。通过引入延长等待时间以后,与之前的算法相比,节点的连通性有了提高。

关键词：传感器网络控制系统等待时间

Delivery of Cas9 Protein into Mouse Zygotes through a Series of Electroporation Dramatically Increases the Efficiency of Model Creation

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journal of Genetics and Genomics 2016年第5期43卷 319-327页

作者： Wenbo Wang Peter M.Kutny Shannon L.Byers Charles j.Longstaff Michael j.DaCosta Changhong Pang Yingfan Zhang Robert A.Taft frank W.Buaas Haoyi Wang The jackson Laboratory Bar Harbor ME 04609 USA State Key Laboratory of Stem Cell and Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Previously we established Zygote Electroporation of Nucleases（ZEN） technology as an efficient and high-throughput way to generate genetically modified mouse ***,there were significant variations of the targeting efficiency among different genomic loci using our previously published *** this study,we improved the ZEN technology by delivering Cas9 protein into mouse zygotes through a series of *** this approach,we were able to introduce precise nucleotide substitutions,large segment deletion and short segment insertion into targeted loci with high efficiency.

关键词： CRISPR-Cas9 Electroporation Mouse zygote