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Chinese science Bulletin 2003年第16期48卷 1748-1752页

作者： LUANRuihong WUFeijian p.h.s.jen sUNXinde CollegeofLifesciences EastChinaNormalUniversityShanghai200062China CollegeofLifesciences CentralChinaNormalUniversityWuhan430079China DivisionofBiologicalsciences UMCMO65211USA

The present study explores the forward mask-ing of the two-tone stimuli in sequence that evoked responses in the inferior colliculus (IC) of the echolocating bats. The results indicate that forward masking is obvious in the acoustic responses of the IC neurons to the two-tone stimuli. Meanwhile the intensity sensitivity of the neurons respond-ing to the probe increases with the inter-tone interval de-creasing. The effects of forward masking are correlated with the relative intensity and the interval between the masker and probe. That is, the effects of forward masking are re-duced with the masker intensity decreasing and enhanced with the probe intensity decreasing and the inter-tone inter-val shortened. The present study suggests that there is a cor-relation between the characteristics of the response to the probe and the dynamic conditions of the postsynaptic cur-rents in the IC neurons.

关键词：神经元回音声音间隔声音探测器前掩蔽 IC 回声定位生理学多突触传递

GABA能抑制调制大棕蝠下丘听神经元时间编码模式

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生物物理学报 2002年第4期18卷 399-403页

作者：栾瑞红 p.h.s.jen 孙心德华东师范大学生命科学学院脑科学研究中心上海200062

大棕蝠(Eptesicusfuscus)下丘神经元对重复率为10 pps(pulse per second)、30 pps的串声刺激均产生跟随反应,但对90 pps串声刺激的跟随反应则不尽相同。微电泳bicuculline阻断GABA能抑制作用后,所记录的58个神经元中,有13个(22%)放电率... 详细信息

大棕蝠(Eptesicusfuscus)下丘神经元对重复率为10 pps(pulse per second)、30 pps的串声刺激均产生跟随反应,但对90 pps串声刺激的跟随反应则不尽相同。微电泳bicuculline阻断GABA能抑制作用后,所记录的58个神经元中,有13个(22%)放电率及串声刺激反应模式无变化;45个(78%)神经元放电率有不同程度的增加,对10 pps、30 pps串声刺激仍能产生跟随反应,但对90 pps串声刺激的跟随反应模式有多种变化。其中: 17个(29%)神经元为放电率增加的跟随反应;9个(15%)神经元放电率增加,对前100 ms的串刺激产生反应且放电密集,而对随后200 ms的串刺激只产生少量的放电;15个(26%)神经元放电率增加,在前几十毫秒范围内有较多的放电反应,后续的反应很弱;4个(7%)神经元只对第一个声刺激产生反应,且放电率增加,随后放电急剧减少。结果提示中脑下丘神经元对听觉信息的时间编码可能具有更复杂的机理。

关键词： GABA GABAA受体串刺激重复率回声定位

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural Regeneration Research 2025年第6期20卷 1707-1708页

作者： siva s.V.p.sakamuri Anil sakamuri Department of Chemistry Auburn University at MontgomeryMontgomeryALUSA Vascular Biology Center and Department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV s.KhATIR T.CUONG-LE school of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for Engineering Application and Technology solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGp) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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The adaptive value of increasing pulse repetition rate during hunting by echolocating bats

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Frontiers in Biology 2013年第2期8卷 198-215页

作者： philip h.-s. jen Division of Biological sciences University of Missouri Columbia MO 65211 USA

During hunting, bats of suborder Microchiropetra emit intense ultrasonic pulses and analyze the weak returning echoes with their highly developed auditory system to extract the information about insects or obstacles. These bats progressively shorten the duration, lower the frequency, decrease the intensity and increase the repetition rate of emitted pulses as they search, approach, and finally intercept insects or negotiate obstacles. This dynamic variation in multiple parameters of emitted pulses predicts that analysis of an echo parameter by the bat would be inevitably affected by other co-varying echo parameters. The progressive increase in the pulse repetition rate throughout the entire course of hunting would presumably enable the bat to extract maximal information from the increasing number of echoes about the rapid changes in the target or obstacle position for successful hunting. however, the increase in pulse repetition rate may make it difficult to produce intense short pulse at high repetition rate at the end of long-held breath. The increase in pulse repetition rate may also make it difficult to produce high frequency pulse due to the inability of the bat laryngeal muscles to reach its full extent of each contraction and relaxation cycle at a high repetition rate. In addition, the increase in pulse repetition rate increases the minimum threshold （i.e. decrease auditory sensitivity） and the response latency of auditory neurons. In spite of these seemingly physiological disadvantages in pulse emission and auditory sensitivity, these bats do progressively increase pulse repetition rate throughout a target approaching sequence. Then, what is the adaptive value of increasing pulse repetition rate during echolocation？ What are the underlying mechanisms for obtaining maximal information about the target features during increasing pulse repetition rate？ This article reviews the electrophysiological studies of the effect of pulse repetition rate on multiple- para

关键词： bat echolocation inferior colliculus multiple-parametric selectivity pulse repetition rate

Corticofugal modulation of frequency tuning of inferior collicular neurons in big brown bat,Eptesicus fuscus

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Chinese science Bulletin 2001年第10期46卷 836-839页

作者： ZhANG Jiping sUN Xinde philip h.-s.jen Department of Biology East China Normal UniversityShanghai 200062China Division of Biological sciences University of Missouri-ColumbiaMO 65211USA

In order to explore the possible mechanism of corticofugal modulation of excitatory frequency tuning curves (EFTCs) of midbrain neurons, we examined the change of sharpness, frequency-intensity response area, minimum threshold of both EFTCs and inhibitory frequency tuning curves (IFTCs) of inferior collicular neurons during corticofugal modulation using two-tone inhibition paradigm and micro-electrical stimulation technique. Our data showed that corticofugal inhibition increased sharpness, minimum threshold, and decreased the frequency-intensity response area of EFTCs, at the same time it decreased the sharpness, minimum threshold but increased the frequency-intensity response area of IFTCs. The opposite results were observed for EFTCs and IFTCs of corticofugally facilitated inferior collicular neurons. During corticofugal inhibition, the percent change of frequency-intensity response area of EFTCs had significant correlation with the percent change of that of IFTCs. These data suggest that cortical

关键词： bat auditory cortex inferior colliculus frequency tuning modulation.

The effects of neural interactions between paired inferior collilular neurons on frequency tuning

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The effects of neural interactions between paired inferior c...

Adaptive mechanisms underlying the bat biosonar behavior

第九次全国生物物理大会学术会议

作者： jen p h-s Division of Biological sciences University of Missouri-ColumbiaMissouriUSA65211

＜正＞ In auditory physiology,processing of auditory information carried by sounds hastraditionally been explained by neural interactions of divergent and convergent projection. As amajor relay nucleus in the auditory pathway, the central nucleus of inferior colliculus （IC）receives complex excitatory and inhibitory inputs from several lower brain stem nuclei,contralateral inferior colliculus, and higher auditory and nonauditory structures. There are also

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Frontiers in Biology 2010年第2期5卷 128-155页

作者： philip h.-s.jen Division of Biological sciences and Interdisciplinary Neuroscience program University of Missouri-ColumbiaMOUSA 65211

For survival,bats of the suborder Microchiropetra emit intense ultrasonic pulses and analyze the weak returning echoes to extract the direction,distance,velocity,size,and shape of the *** these bats and other mammals share the common layout of the auditory pathway and sound coding mechanism,they have highly developed auditory systems to process biologically relevant pulses at the expense of a reduced visual *** this active biosonar behavior,they progressively shorten the pulse duration,decrease the amplitude and pulse-echo gap as they search,approach and finally intercept the ***,these changes in multiple pulse parameters throughout the entire course of hunting enable them to extract maximal information about localized prey from the returning *** hunt successfully,the auditory system of these bats must be less sensitive to intense emitted pulses but highly sensitive to weak returning *** also need to recognize and differentiate the echoes of their emitted pulses from echoes of pulses emitted by other *** studies have shown the following mechanical and neural adaptive mechanisms underlying the successful bat biosonar behavior:(1)Forward orienting and highly mobile pinnae for effective scanning,signal reception,sound pressure transformation and mobile auditory sensitivity;(2)Avoiding and detecting moving targets more successfully than stationary ones;(3)Coordinated activity of highly developed laryngeal and middle ear muscles during pulse emission and reception;(4)Mechanical and neural attenuation of intense emitted pulses to prepare for better reception of weak returning echoes;(5)Increasing pulse repetition rate to improve multiple-parametric selectivity to echoes;(6)Dynamic variation of duration selectivity and recovery cycle of auditory neurons with hunting phase for better echo analysis;(7)Maximal multiple-parametric selectivity to expected echoes returning within a time window after pulse emission;(8)pu

关键词： adaptive mechanisms bat biosonar behavior

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOssEINI O.BALILAshAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

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GENETIC CONsEQUENCEs OF INTRODUCED Gouramy helostoma Temminckii (pisces: helostomatidae) IN BRUNEI's WETLAND

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湿地科学 2003年第1期1卷 51-56页

作者： h.s.Zohrah p.h.C.Fauzani C. s. jen O. Norsuzieyanti

Kissing gouramy (helostoma temminckii) was introduced into Tasek Merimbun in the 1980's. We studied their genetic profile using allozyme electrophoresis and found that all loci were monomorphic. The loss of heterozygotes may suggest that the gouramy are inbreds. They must have reproduced by repeated sib-mating over the years. The severe drought in Tasek Merimbun may have aggravated the genetic erosion further. The genetic variability of kissing gouramy in terms of % polymorphic loci, mean number of alleles per loci and observed heterozygosity level were lower than cyprinids in the same lake and kissing gouramy from the wild. We also note that kissing gouramy is a fast grower and may threaten the livelihood of indigenous fishes in the lake.

关键词： Kissing gouramy introduced allozyme electrophoresis