检索结果-南通市图书馆

Simulations of a logistic-type model with delays for Chagas disease with insecticide spraying

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2017年第3期10卷 41-60页

作者： Nofe Al-Asuoad tyler Pleasant Meir Shillor Hrishikesh Munugala Daniel J. Coffield Jr. Anna Maria Spagnuolo Department of Mathematics and Statistics Oakland University Rochester MI 48309 USA Harrison High School MI USA Novi High School Novi MI 48375 USA Mathematics Department University of Michigan-Flint Flint MI 48502 USA

This work studies and numerically simulates a logistic-type model for the dynamics of Chagas disease, which is caused by the parasite T. cruzi and affects millions of humans and domestic mammals throughout rural areas in Central and South America. A basic model for the disease dynamics that includes insecticide spraying was developed in Spagnuolo et al. （2010） [271 and consists of a delay-differential equation for the vectors and three nonlinear ordinary differential equations for the populations of the infected vectors, infected humans and infected domestic mammals. In this work, the vector equation is modified by using a logistic term with zero, one or two delays or time lags. The aim of this study is three-fold： to numerically study the effects of using different numbers of delays on the model behavior; to find if twice yearly insecticide spraying schedules improve vector control; and to study the sensitivity of the system to the delays in the case of two delays, by introducing randomness in the delays. It is found that the vector equation with different number of delays has very different solutions. The ＂best＂ day of spraying is the middle of Spring and twice annual sprayings cause only minor improvements in disease control. Finally, the model is found to be insensitive to the values of the delays, when the delays are randomly distributed within rather narrow intervals or ranges centered on the parameter values used in Coffield et al. （2014） [8].

关键词： Chagas disease logistic equation with delays epidemic dynamics nonlinear dynamical system simulations.

Stripe Rust Effector PstGSRE1 Disrupts Nuclear Localization of ROS-Promoting Transcription Factor TaLOL2 to Defeat ROS-Induced Defense in Wheat

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2019年第12期12卷 1624-1638页

作者： Tuo Qi Jia Guo Peng Liu Fuxin He Cuiping Wan Md Ashraful Islam Brett M.tyler Zhensheng Kang Jun Guo State Key Laboratory of Crop Stress Biology for Arid Areas College of Plant ProtectionNorthwest A&F UniversityYangling 712100ShaanxiP.R.China Center for Genome Research and Biocomputing Oregon State UniversityCorvallisORUSA

Puccinia striiformis ***(Pst),a biotrophic plant pathogen,secretes numerous effectors to modulate host defense *** the molecular mechanisms by which Pst effectors regulate wheat immunity is of great importance for the development of novel strategies for durable control of stripe *** this study,we identified a glycine-serine-rich effector gene,PstGSRE1,which is highly induced dur-ing early *** expression of PstGSRE1 RNAi constructs in wheat significantly reduced virulence of Pst and increased H2O2 accumulation in ***1 was shown to target the reactive ox-ygen species(ROS)-associated transcription factor TaLOL2,a positive regulator of wheat ***1 disrupted nuclear localization of TaLOL2 and suppressed ROS-mediated cell death induced by TaLOL2,thus compromising host *** work reveals a previously unrecognized strategy whereby rust fungi exploit the PstGSRE1 effector to defeat ROS-associated plant defense by modulating the subcellular compartment of a host immune regulator and facilitate pathogen infection.

关键词： host-induced gene silencing effector glycine-serine-rich transcription factor Puccinia striiformis f.sp.tritici reactive oxygen species

Pheromone pollution from invasive sea lamprey misguides a native confamilial

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2021年第3期67卷 333-335页

作者： tyler J.Buchinger Skye D.Fissette Belinda HUERTA Ke Li Nicholas S.Johnson Weiming Li Department of Fisheries and Wildlife Michigan State UniversityEast LansingMl 48825USA U.S.Geological Survey Great Lakes Science CenterHammond Bay Biological StationMillersburgMl49759USA

Animals interact with mates in a sensory environment rife with the footprints of human *** chorus over the noise of traffic(Bee and Swanson 2007),glow-worms search for bioluminescent mates against backlight from street lamps(Bird and Parker 2014),and fish attend to conspecific olfactory cues mixed with sewage(Fisher et al.2006).As invasive species proliferate throughout the world,animals also encounter noise in the form of novel heterospecific signals that can interfere with existing communication channels(Groning and Hochkirch 2008).Pheromones,for example,are often species-specific in natural contexts involving sympatric heterospecifics but may become detrimental pollution when animals invade regions inhabited by historically allopatric relatives that previously faced less selection for signal divergence(Gozlan et al.2014).

关键词： Hoc Bee pollution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

信息安全的经济学(之一)

中国教育网络 2007年第12期 27-29页

作者： Ross anderson tyler Moore 陆俊秀

信息安全的经济学近来已经成为一门蓬勃发展的学科。由于分布式系统通常是由那些属于不同利益主体的计算机构成,我们发现在实现可靠性的过程中,激励机制变得和纯技术设计一样重要。这一学科领域不仅为那些传统的安全课题提供了参照,还... 详细信息

信息安全的经济学近来已经成为一门蓬勃发展的学科。由于分布式系统通常是由那些属于不同利益主体的计算机构成,我们发现在实现可靠性的过程中,激励机制变得和纯技术设计一样重要。这一学科领域不仅为那些传统的安全课题提供了参照,还为更广泛领域中的研究难题拓展了思路,诸如:P2P系统设计,程序员和测试员的最优比例,隐私为何不断被侵犯,以及数字版权管理中的相关问题等。本期和下期推荐剑桥大学计算机实验室的Ross anderson和tyler Moore在2006年10月27日《科学》杂志上刊发的《信息安全的经济学(The Economics of Information Security)》一文,介绍这一学科的研究和发展,以资借鉴。

关键词：信息安全经济学分布式系统学科领域数字版权管理计算机实验室《科学》杂志利益主体

在线全文

学校读者我要写书评

暂无评论

完美数及其相关问题

数学进展 2024年第4期53卷 673-689页

作者：蔡天新 tyler ROSS 浙江大学数学科学学院杭州浙江310058

完美数问题是最古老的数学问题之一,可能来源于古希腊的毕达哥拉斯学派,被意大利当代数学家奥迪弗雷迪列为面向21世纪的“四大数学难题”之首.本文对古老的完美数问题及相关的梅森素数进行综述,尤其是对其拓展为平方完美数、立方完美数... 详细信息

完美数问题是最古老的数学问题之一,可能来源于古希腊的毕达哥拉斯学派,被意大利当代数学家奥迪弗雷迪列为面向21世纪的“四大数学难题”之首.本文对古老的完美数问题及相关的梅森素数进行综述,尤其是对其拓展为平方完美数、立方完美数及S-完美数以后所产生的问题进行了综述.

关键词：完美数平方完美数立方完美数 S-完美数

在线全文

学校读者我要写书评

暂无评论

信息安全的经济学(之二)

中国教育网络 2008年第1期 31-33页

作者： Ross anderson tyler Moore 陆俊秀

信息安全的经济学近来已经成为一门蓬勃发展的学科。由于分布式系统通常是由那些属于不同利益主体的计算机构成,我们发现在实现可靠性的过程中,激励机制变得和纯技术设计一样重要。这一学科领域不仅为那些传统的安全课题提供了洞见,而... 详细信息

信息安全的经济学近来已经成为一门蓬勃发展的学科。由于分布式系统通常是由那些属于不同利益主体的计算机构成,我们发现在实现可靠性的过程中,激励机制变得和纯技术设计一样重要。这一学科领域不仅为那些传统的安全课题提供了洞见,而且还为更宽泛的领域中的研究难题拓展了思路,诸如:P2P系统设计,程序员和测试员的最优比例,隐私为何不断被侵蚀,以及数字版权管理等问题。本刊上期和本期推荐剑桥大学计算机实验室的Ross anderson和tyler Moore在2006年10月27日的《科学》杂志上刊发的《信息安全的经济学(The Economics of Information Security)》一文,介绍这一学科的研究和发展,以资借鉴。

关键词：信息安全数字版权管理软件安全经济学家软件风险漏洞市场攻击者

Evaluation of ambient mass spectrometry tools for assessing inherent postharvest pepper quality

在线全文

学校读者我要写书评

暂无评论

Horticulture Research 2021年第1期8卷 2252-2259页

作者： tyler J.Mason Harmonie M.Bettenhausen Jacqueline M.Chaparro Mark E.Uchanski Jessica E.Prenni Department of Horticulture and Landscape Architecture Colorado State UniversityFort CollinsCO 80524USA

Horticulturists are interested in evaluating how cultivar,environment,or production system inputs can affect postharvest *** mass spectrometry approaches enable analysis of minimally processed samples under ambient conditions and offer an attractive high-throughput alternative for assessing quality characteristics in plant ***,we evaluate direct analysis in real time(DART-MS)mass spectrometry and rapid evaporative ionization-mass spectrometry(REIMS)to assess quality characteristics in various pepper(Capsicum annuum L.)***-MS exhibited the ability to discriminate between pod colors and pungency based on chemical fingerprints,while REIMS could distinguish pepper market class(e.g.,bell,lunchbox,and popper).Furthermore,DART-MS analysis resulted in the putative detection of important bioactive compounds in human diet such as vitamin C,p-coumaric acid,and *** results of this study demonstrate the potential for these approaches as accessible and reliable tools for high throughput screening of pepper quality.

关键词： cultivar pepper ambient

The Effect of Circuit Training on Resting Heart Rate Variability, Cardiovascular Disease Risk Factors and Physical Fitness in Healthy Untrained Adults

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Health 2016年第2期8卷 144-155页

作者： Adamos Vrachimis Marios Hadjicharalambous Chris tyler School of Human & Life Sciences Roehampton University London UK Department of Life & Health Sciences University of Nicosia Nicosia Cyprus

The purpose of the present study was to examine the effect of circuit training (CT) on resting heart rate variability (HRV) and other cardiovascular disease (CVD) risk factors such as blood lipids and blood glucose and on fitness components. Twenty-four healthy untrained adults (age 26.5 ± 5.1 years;height 1.67 ± 8.4 m;weight 66.8 ± 15.1 kg;26.3% ± 5.2%;maximum oxygen uptake (VO2max) 48.5 ± 10.0 ***-1.min-1) were assigned to either CT (n = 12) involving bodyweight exercises, or control (CON, n = 12) groups. Prior to the start and following the end of the six-week training period, time-, frequency-domain and nonlinear measures of resting HRV, arterial blood pressure, body composition, fasting blood lipids, lipoproteins and glucose, VO2max, upper body muscular endurance (UBME) and abdominal and hip flexor (AHFME), back strength (BS) and handgrip were assessed. None of the resting HRV measures (P > 0.05) were affected by the CT intervention. However, diastolic blood pressure decreased (P = 0.03), lean body weight (P = 0.03) increased, VO2max (P = 0.03), UBME (P = 0.001), AHFME (P = 0.04), and BS (P = 0.03) were significantly higher following CT, whereas the other variables were not influenced by the CT. Six-week of CT involving bodyweight exercises has no significant impact on resting HRV. However, this type of training might decrease the risk for development of CVD by reducing arterial blood pressure and by improving body composition, aerobic capacity, muscular endurance and strength.

关键词： Heart Rate Variability Circuit Training Healthy Untrained Adults

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

溪洛渡水库水温日变化的测量与分析

水科学进展 2018年第4期29卷 523-536页

作者：谢奇珂刘昭伟陈永灿陈啸 Kenneth tyler Werk 清华大学水沙科学与水利水电工程国家重点实验室北京100084 西南科技大学环境与资源学院四川绵阳621010

溪洛渡等河道型水库具有库容大且径流量大的特点,热动力过程和水温分布迥异于天然河流或湖泊。通过温度链对溪洛渡水库坝前水温进行长期高频监测,选取升温期和降温期典型时段,分析表层水温的昼夜变化和温跃层的内波现象;计算表面热交换... 详细信息

溪洛渡等河道型水库具有库容大且径流量大的特点,热动力过程和水温分布迥异于天然河流或湖泊。通过温度链对溪洛渡水库坝前水温进行长期高频监测,选取升温期和降温期典型时段,分析表层水温的昼夜变化和温跃层的内波现象;计算表面热交换,并分析其对水温变化的影响。结果表明:水面混合层在水面热交换的控制下周期性出现和消失;在升温期水面吸热对于变温层升温过程有重要影响;在降温期,水面失热驱动了垂向混合,入流降温形成侵入流,共同控制变温层的降温过程;温跃层中24 h周期的内波形成与出流日调节有直接因果关系。与实测数据计算的水面热通量相比,采用气象站日值数据的溪洛渡数值模型的模拟值偏小。

关键词：水温水面热交换日变化溪洛渡水库