Genetic Variation among various populations of spadefoot toads (<i>Pelobates syriacus</i>, Boettger, 1869) at breeding sites in northern Israel

A genetic study was carried out on spadefoot toads (Pelobates syriacus) from habitats of various locations and altitudes in northern Israel. Cytochrome b and 12S were amplified by PCR for the analysis of genetic variation based on five DNA polymorphisms and for RAPD PCR. The nucleotide sequences of the mitochondrial DNA fragments were determined from a 460 bp clone of cytochrome b and a 380 bp clone of 12S (GenBank accession numbers, FJ595199-FJ59-5203). No genetic variation was found among the populations with regard to 12S. According to the analysis of five sequences using Arlequin software, there was a high gene identity among the populations (98.7%-99.6%). Both populations, Elrom Pond breeding site, at the highest altitude and Fara Pond, at the lowest, had the lowest identities as compared to other populations. The DNA variation among P. syri-acus populations from various breeding sites, according to band sharing (BS), when using the OP-4 primer, was 0.92-1.00. Similarity was low between the population of Elrom Pond and the populations of Kash Pond, Raihania Pond and Sasa Pond (0.92 BS), as well as between the population of Fara Pond at the lowest altitude, and the populations of Kash Pond, Raihania Pond and Sasa Pond (0.92 BS). Similar results were obtained when comparing the results obtained using primer OPA-3. The lowest similarity was found between populations of the highest altitude (Elrom Pond) and lowest altitude (Fara Pond), relative to the other ponds (Kash Pond, Raihania Pond and Sasa Pond) with a BS of 0.93.

Intracellular recording and morphology of tectal neurons activated by contralateral nucleus isthmi in toads

THE nucleus isthmi (NI) in lower vertebrates and its mammalian analogue, the nucleus para-bigeminalis, are all visual centres. They receive their tectal input ipsilaterally and project backipsilaterally in teleosts and birds, or bilaterally in amphibians and reptiles, as well as in mam-mals. It is well known that NI receives its visual excitation through the ipsilateral optic tec-tum (OT). NI mainly exerts inhibition on the ipsilateral OT in frogs.A recent study

Commissural connections electrophysiologically identifled between tectum and nucleus isthmi in toads

It has been established that the nucleus isthmi (NI) in lower vertebrates and its mammalian analogue, the nucleus parabigeminalis, receive input from the ipsilateral tectum and project back ipsilaterally in teleosts and birds, or bilaterally in amphibians, reptiles and mammals.The nucleus receives visual excitation from the ipsilateral tectum. while it mainly exerts inhibition on cells recorded from the ipsilateral tectum. A recent study by Wang and coworkers shows that the nucleus isthmi pars magnoceUularis (Imc) and

Hibernation with rhythmicity:the circadian clock and hormonal adaptations of the hibernating Asiatic toads(Bufo gargarizans)

Hibernation is one of the fundamental strategies in response to cold environmental temperatures.During hibernation,the endocrine and circadian systems ensure minimal expenditure of energy for survival.The circadian rhythms of key hormones,melatonin(MT),corticosterone(CORT),triiodothyronine(T3),and thyroxine(T4),and the underlying molecular regulatory mechanisms of hibernation have been well determined in mammals but not in ectotherms.Here,a terrestrial hibernating species,Asiatic toad(Bufo gargarizans),was employed to investigate the plasma CORT,MT,T3,and T4;and the retina,brain,and liver mRNA expression of the core clock genes,including circadian locomotor output cycles kaput(Clock),brain and muscle ARNT-like 1(Bmal1),cryptochrome(Cry)1 and 2,and period(Per)1 and 2,at 7-time points over a 24-h period under acute cold(1 day at 4℃),and hibernation(45 days at 4℃).Our results showed that the circadian rhythms of the core clock genes were rather unaffected by acute cold exposure in the retina,unlike the brain and liver.In contrast,during hibernation,the liver clock genes displayed significant circadian oscillations,while those in the retina and brain stopped ticking.Furthermore,plasma CORT expressed circadian oscillations in both groups,and T3 in acute cold exposure group,whereas T4 and MT did not.Our results reveal that the plasma CORT and the liver sustain rhythmicity when the brain was not,indicating that the liver clock along with the adrenal clock synergistically maintains the metabolic requirements to ensure basic survival in hibernating Asiatic toads.

Habitat Suitability and Distribution Pattern Response to Global Climate Change in a Widespread Species,the Asiatic Toad(Bufo gargarizans)

The distribution and diversity of the species are closely related to the global climate.As the most widely distributed species of Bufonidae in China,the study of the distribution pattern and habitat suitability of the Asiatic toad under climate change can help us understand the reply pattern of Bufonidae habitat to climate change.Here,combined with the Maxent model and GIS technology,the effects of climate change on the distribution pattern and habitat suitability of the Asiatic toad were comprehensively analyzed.The results show that the rainfall during the wettest season(Bio16)and the mean temperature of the driest season(Bio9)have a considerable impact on the distribution of the Asiatic toad.In the next 30 to 50 years,across the overall spacial scale of the Chinese mainland,the habitat of the Asiatic toad will be primarily in the eastern part of China and less in south part,while its distribution area will expand to the midwest and northwest parts of China.Overall,the area in which it can be distributed will be reduced and suitable habitat will shift to some regions of higher latitude and elevation.In a word,we systematically analyzed the changes of the distribution pattern and habitat suitability of the Asiatic toad with climate change,and we aim to provide data on how climatic variation may impact amphibians.

Determination of the Content of Five Active Components in Toad Skin

[Objectives] To establish a method for the determination of active components in toad skin. [Methods] HPLC method was used to determine the content of five active components (bufotalin, cinobufotalin, bufalin, cinobufagin and resibufogenin) in toad skin. [Results] Chromatographic conditions are as follows: Agilent ZORBAX SB-C 18 chromatographic column was used;acetonitrile (A)-0.3% glacial acetic acid (B) gradient elution (0-15 min, 28%A-54%A;15-35 min, 54%A-54%A) was conducted;the flow rate was 0.6 mL/min;the detection wavelength was 296 nm;the column temperature was 30 ℃;the sample size was 10 μL. Under the above conditions, the determination method of the five components can be established at one time. [Conclusions] The method was stable and reliable, and can provide experimental basis for the development and utilization of active ingredients in toad skin.

小信号增益及环时间非对称性对TOAD开关特性的影响

充分考虑了太赫兹光非对称解复用器 (TOAD)中半导体光放大器 (SOA)的增益饱和与恢复的影响 ,深入分析研究了小信号增益及环时间非对称性对TOAD开关特性的影响 .结果表明 :小信号增益对开关窗口的形状影响显著 ,但对宽度影响很小 ;在环中点附近的某一定范围内 ,TOAD解复用输出随环时间非对称性的变化而急剧变化 。

利用Toad解决Oralce数据库表空间错误问题

数据库是整个信息系统的核心,传统方式的数据库管理一般采用Sqlplus等命令行工具书写SQL命令。相比之下,使用数据库管理工具Toad连接数据库,通过图形化界面解决数据库问题,减少操作失误和繁琐程度,有效降低数据库管理成本。

TOAD中半导体光放大器的动态增益响应及光脉冲传输特性研究

讨论了太赫兹光非对称解复用器中半导体光放大器 (SOA)对具有不同能量和脉宽的控制脉冲的动态增益响应 ,研究了不同的逆时针信号脉冲和控制脉冲时延的情况下通过 SOA后的逆时针信号脉冲的功率和相位变化。

非线性元件的偏移量对TOAD开关窗口的影响

通过数值模拟研究了非线性元件的偏移量对ＴＨｚ光学非对称解复用器开关窗口的影响，结果表明，ＴＨｚ光学非对称解复用器的开关窗口宽度随其时间非对称量作周期性变化，周期为控制脉冲周期的一半。理论计算结果与实验结果完全吻合。

“军卫一号”数据库Oracle 8.17到Oracle 11g的升级

目的:解决服务器负载过重及数据库并发数过多导致客户端无法连接的难题,实现"军卫一号"数据库从Oracle 8.17到Oracle 11g的平稳升级。方法:利用数据库自带的导入/导出(Exp/Imp)工具以及Oracle应用开发工具(tools of Oracle application developmers,Toad),生成并修改相关升级语句,导出、导入数据库数据,实现数据库的跨平台、跨版本升级。结果:成功实现了数据库升级,系统运行速度大大提高。结论:该方案简便易行、升级时间短、可操作性强、数据零丢失,系统运行稳定,适合中小医院推广应用。

基于QDSOA-TOAD结构的NRZ-RZ格式转换器

针对光网络中非归零(NRZ)与归零(RZ)格式转换的问题,利用量子点半导体光放大器(QD-SOA)的快速非线性效应和全光非对称解复用器(TOAD)干涉结构,提出了一种基于QDSOA-TOAD结构的光数据格式转换器,可以实现高速格式转换,且在很大程度上减少了频率啁啾对转换信号的影响。通过系统建模,验证了160Gbit/s NRZ-RZ光信号格式转换的可行性和有效性;并给出了关键参数的选择范围。通过合理设置系统参数,可以获得较高的输出品质因子Q。

Microelectronic neural bridging of toad nerves to restore leg function

The present study used a microelectronic neural bridge comprised of electrode arrays for neural signal detection, functional electrical stimulation, and a microelectronic circuit including signal amplifying, processing, and functional electrical stimulation to bridge two separate nerves, and to restore the lost function of one nerve. The left leg of one spinal toad was subjected to external mechanical stimulation and functional electrical stimulation driving. The function of the left leg of one spinal toad was regenerated to the corresponding leg of another spinal toad using a microelectronic neural bridge. Oscilloscope tracings showed that the electromyographic signals from controlled spinal toads were generated by neural signals that controlled the spinal toad, and there was a delay between signals. This study demonstrates that microelectronic neural bridging can be used to restore neural function between different injured nerves.

单向和双向控制脉冲TOAD的开关窗口研究

详细研究了单控制脉冲TOAD(terahertz optical asymmetric demultiplexer)结构开关窗口的非对称缺陷及其产生机理。通过理论分析和optisystem仿真证实了双控制脉冲TOAD结构能够很好地解决单控制脉冲TOAD结构的开关窗口缺陷。仿真结果显示,双控制脉冲TOAD获得了波形对称、对比度更高的开关窗,详细解释了仿真中出现的双峰现象。

Testing Hypotheses of Pleistocene Population History Using Coalescent Simulations: Refugial Isolation and Secondary Contact in Pseudepidalea raddei (Amphibia: Bufonidae)

The impact of the Quaternary glaciation on eastern China’s local fauna and flora is a topic of considerable interest. We use mitochondrial DNA(mtDNA) sequences and coalescent simulations to test two general biogeographic hypotheses related to the effect of the Pleistocene climatic fluctuations on a widespread, eastern Chinese amphibian, Pseudepidalea raddei. Genealogical reconstructions are made and they detect major western and eastern lineages, which overlap in northwestern China, and possibly indicate the secondary contact of the populations that had entered the region from separate glacial refugia. Coalescent tests rejected alternative hypotheses of fragmentation of either a widespread ancestor or panmixia. The tests instead supported the hypothesis of geographic isolation and a remarkable dispersal pattern in one of the lineages. Though the Pleistocene climatic events are known to have affected the historical distributions and intra-specific divergence of Chinese squamates, coalescent and non-coalescent demographic analyses indicated that the toad P. raddei was not adversely affected by glacial cycling. Presumably, an increase in the amount of climatically mild habitats in East Asia is due to the development of monsoons since the Mid-late Pleistocene is responsible for the relatively mild effects.

No Male Preference for Large Females in the Asian Common Toad(Duttaphrynus melanostictus):Effect of the Sex Ratio and Breeding System

Mating preferences are common in natural populations of animals.Numerous studies have shown that male mate choice can occur in a wide range of taxa.However,male mating preferences are still poorly understood in anurans.Sexual selection theory predicts that male mate choice is not expected to arise if 1) adult population exhibited a highly male-biased sex ratio which will diminish male mating success;2) males provide less parental care;3) mating success of males is associated with chorus tenure in which males would maximize their fitness by mating with multiple mates.We tested these predictions in the Asian common toad Duttaphrynus melanostictus from southeastern Tibet,China.Our field experimental results indicated that,the breeding population exhibited a highly male-biased sex ratio,called males did not defend sites which contain significant resources required by females and offspring,both sexes provided no parental care after egg-laying,and the toad species was characterized with prolonged breeding season chorus attendance.In male mate choice experiment,males did not show preferences for a larger gravid female over a smaller gravid female.We suggest that male mating success in the Asian common toad is likely determined by the number but not the quality of mates.Future research should focus on how sexual selection on male acoustic signaling and how female preference exert different types of selection pressure on male call traits in this Tibet toad.

Experimental culture of non-indigenous Juncus bufonius from King George Island, South Shetland Island, Antarctica

Juncus bufonius L. （Juncaceae） is recognized by the US Department of Agriculture as a weed or invasive plant. Recently, we reported on 3i bufonius L. var. bufonius associated with the native vascular plants Deschampsia antarctica and Colobanthus quitensis in the environs of the Polish Arctowski Station, King George Island, in the Maritime Antarctica. In this study, we evaluated the developmental stages and morphological characteristics of J. bufonius plants cultivated in controlled conditions beginning with seeds obtained from plants of the Antarctic population. Germination occurred at 3 weeks and the germination percentage was low （22.5%）. The average time between the anthesis and seed formation was 7 weeks, similar to that reported for other species in the Juncaceae. According to data reported in the literature, Antarctic individuals were significantly smaller than their relatives growing in other conditions, except for the number of inflorescences. The morphological characteristics of a species vary according to its distribution and the edaphoclimatic environment where it occur; cosmopolitan plants shuch as J. bufonius also have reduced stature in cold environments. The low percentage germination may have been due to water availability in the plant chamber in which the study was conducted. J. bufonius is intolerant of dry environments, and once it suffers hydric stress its recovery is very low; thus, a moister environment could be beneficial. J. bufonius has become established amongst native vegetation near Arctowski Station and without careful control or eradication; it may have the potential to spread far beyond the site, as has happened with the alien grass Poa annua as human disturbance and climate warming increase.

Experimental Investigation of All-Optical NRZ-DPSK to RZ-DPSK Format Conversion Based on TOAD

We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying （NRZ-DPSK） to return-to-zero differentiM-phase-shift-keying （RZ-DPSK） format conversion scheme. This scheme is based on the terahertz optical asymmetric demultiplexer （TOAD）. A 10 Gb/s converted RZ-DPSK signal is obtained with a wide duty cycle tuning range from 16% to 66%. For all converted RZ-DPSK signals, the receiver sensitivities at BER of 10-9 are 0.4 to 1.7dB higher compared with the original NRZ-DPSK signal. The clear and open eye diagrams are presented to demonstrate the high quality format conversion performance. Moreover, the optical spectra show that this conversion is in a wavelength-preserving operation.

Guardians of the Corn: The Snake, The Bat and the Toad in Pre-Columbian Mayan Art of the Classic Period (ca. 250-900 CE)

The conflict and congruity of dualistic approaches to the world inundate the illustration of agricultural production in the Pre-Columbian Art of the Maya.Crop production is co-dependent on human factors,environmental factors and animal factors.The symbiosis of these elements generated success or failure in harmony with the natural world.This paper explores the relationship of three animals to successful crop production with particular attention placed on the cane toad,as this creature has often been confused with frogs or underplayed in earlier academic research.The cane toad is a powerful force in organic farming,functioning as a deterrent to destructive pests.In addition,the cane toad produces powerful hallucinogenic substances for humans,while at the same time,repelling predators with its bitter taste,acrid smell and poison.This bufo-toxin is a powerful substance that links the toad with the Underworld origins of the maize.

把消费的个性突出来

在近些年的消费市场上人们颇爱赶潮流,从而推动市场盛行着两个字:一个是“优”,一个是“洋”,而且很多时候“优”的不及“洋”的。“洋”和“优”又多有假的,宰人、坑人的事接踵而来。 出现这种现象的主要原因,有些人的消费行为是不介意价值而注重于价格,更多地偏于从众。