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991.
Flying mate detection and chasing by tsetse flies (Glossina) 总被引:1,自引:0,他引:1
JOHN BRADY 《Physiological Entomology》1991,16(2):153-161
Abstract Male tsetse flies, probably Glossina morsitans morsitans Westw., were video-recorded in the field as they took off and chased other tsetse flies. Chasers responded (took off) to a target fly at a maximum distance of c. 55 cm, when it subtended c. 1.6o to their eye (–1 foveal ommatidial subtense). Chased targets were always within this range (mean subtense at take-off = 3.2o ) and approaching the chaser. The most significant difference between chased and non-chased targets was in the rate of approach of the target fly in terms of the increase in its image size immediately before the chaser took off ( 21o s−1 ), especially as its relative increase (690% s-1 P< 0.005). No feature of the target's translational velocity, nor any relationship between that and the image size approached this level of significance. Chasers seemed to 'slipstream' their target at c. 20 cm directly behind it, perhaps suggesting target identification by speed matching. Chases were apparently abandoned when the target image shrank from covering at least two of the chaser's foveal ommatidia to covering only one. Parallax-free measurements of flight speeds indicated a preferred, stable mean groundspeed of 4.8±0.1 m s_1 (SE), at a mean wing-beat frequency of 209±3 Hz. 相似文献
992.
Walter Heiligenberg Clifford H. Keller Walter Metzner Masashi Kawasaki 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,169(2):151-164
Summary The complex of the diencephalic nucleus electrosensorius (nE) provides an interface between the electrosensory processing performed by the torus semicircularis and the control of specific behavioral responses. The rostral portion of the nE comprises two subdivisions that differ in the response properties and projection patterns of their neurons. First, the nEb (Fig. 1 B), which contains neurons that are driven almost exclusively by beat patterns generated by the interference of electric organ discharges (EODs) of similar frequencies. Second, the area medial to the nEb, comprising the lateral pretectum (PT) and the nE-acusticolateralis region (nEar, Fig. 1 B-D), which contains neurons excited predominantly by EOD interruptions, signals associated with aggression and courtship. Neurons in the second area commonly receive convergent inputs originating from ampullary and tuberous electroreceptors, which respond to the low-frequency and high-frequency components of EOD interruptions, respectively. Projections of these neurons to hypothalamic areas linked to the pituitary may mediate modulations of a fish's endocrine state that are caused by exposure to EOD interruptions of its mate.Abbreviations
a
axon
-
ATh
anterior thalamic nucleus
-
CCb
corpus cerebelli
-
CE
central nucleus of the inferior lobe
-
CP
central posterior thalamic nucleus
-
Df
frequency difference between neighbor's EOD and fish's own
-
DFl
nucleus diffusus lateralis of the inferior lobe
-
DFm
nucleus diffusus medialis of the inferior lobe
-
DTn
dorsal tegmental nucleus
-
EOD
electric organ discharge
-
G
glomerular nucleus
-
Hc
caudal hypothalamus
-
Hd
dorsal hypothalamus
-
Hl
lateral hypothalamus
-
Hv
ventral hypothalamus
-
JAR
jamming avoidance response
-
LL
lateral lemniscus
-
MGT
magnocellular tegmental nucleus
-
MLF
medial longitudinal fasciculus
-
nB
nucleus at the base of the optic tract
-
nE
nucleus electrosensorius
-
nEar
nucleus electrosensorius-acusticolateral region
-
nEb
nucleus electrosensorius-beat related area
-
nE
nucleus electrosensorius, area causing rise of EOD frequency
-
nE
nucleus electrosensorius, area causing fall of EOD frequency
-
nLT
nucleus tuberis lateralis
-
nLV
nucleus lateralis valvulae
-
PC
posterior commissure
-
Pd
nucleus praeeminentialis, pars dorsalis
-
PeG
periglomerular complex
-
PG
preglomerular nucleus
-
PLm
medial division of the perilemniscal nucleus
-
Pn
pacemaker nucleus
-
PPn
prepacemaker nucleus
-
PT
pretectal nucleus
-
PTh
prethalamic nucleus
-
R
red nucleus
-
Sc
suprachiasmatic nucleus
-
SE
nucleus subelectrosensorius
-
TAd
nucleus tuberis anterior-dorsal subdivision
-
TAv
nucleus tuberis anterior-ventral subdivision
-
TeO
optic tectum
-
TL
torus longitudinalis
-
TSd
dorsal (electrosensory) torus semicircularis
-
TSv
ventral (mechanosensory and auditory) torus semicircularis
-
tTB
tecto-bulbar tract
-
VCb
cerebellar valvula
-
VP
valvular peduncle
-
VPn
nucleus of the valvular peduncle 相似文献
993.
本文运用抗人巨细胞病毒(HCMV)包膜20KD或/和130KD结构蛋白的单克隆抗体分别建立了4类酶联免疫吸附试验(ELISA)夹心法,共对44人份临床尿标本进行HCMV抗原检测。方法的敏感度可高达10.3—32.8ng HCMV抗原/ml尿,与尿标本中的HSV-Ⅰ、HSV-Ⅱ和EBV抗原无交叉反应,重复性良好,与病毒分离比较,敏感性和特异性在71—83%和88—100%之间;与核酸杂交比较,敏感性和特异性也可分别高达60—100%和83.3—100%。混合使用多种单克隆抗体作为包被抗体会得到较好的技术参数。上述结果提示运用单克隆抗体ELISA将有助于一般临床实验室对HCMV感染的快速诊断。 相似文献
994.
Persistence of viable and heat-killed vegetative cells, parasporal crystals, and spores of Bacillus thuringiensis in soil was monitored by immunofluorescence. The rates of disappearance of the different bacterial components decreased in the following order: viable cells, heat-killed cells, parasporal crystals, and spores. Vegetative cells disappeared at rapid, exponential rates; viable cells autolysed, whereas heat-killed cells were digested by an actinomycete-like, soil microorganism. Parasporal crystals disappeared at a slower, nonexponential rate. Numbers of spores remained unaltered throughout 91 days incubation at 25°C and no germination was detected in this period. 相似文献
995.
Tibor Jermy Árpád Szentesi Judit Horváth 《Entomologia Experimentalis et Applicata》1988,49(1-2):83-98
A short critical review is given on the literature of host plant finding in phytophagous insects with main emphasis on the Colorado potato beetle (Leptinotarsa decemlineata Say, col.: Chrysomelidae). The literature data are compared with the results of field experiments: (1) the foraging behaviour of adults was observed in a field arena on bare ground, and (2) adults were released in closed plant stands and recaptured by potted potato plants. It is concluded that host plant finding is a chance event in this species. The observed high directionality of move must be an adaptation increasing probability of host finding. Implications on population dynamics and agricultural practice are discussed. 相似文献
996.
Studies on acetylcholine sensor and its analytical application based on the inhibition of cholinesterase 总被引:7,自引:0,他引:7
Acetylcholine esterase electrodes, based on glass, Pd/PdO and Ir/IrO2 electrodes as pH sensor, using the immobilized acetylcholine esterase in acrylamide-methacrylamide hydrazides prepolymer are reported and compared. New data on the analysis of nicotine, fluoride ion, and some organophosphorus compounds are reported using the present AChE sensor based on the inhibition of the immobilized acetylcholine esterase. Reactivation of immobilized AChE after inhibition with reversible inhibitor, i.e. nicotine and fluoride ion is carried out using a mixture of working buffer and acetylcholine, whereas reactivation after inhibition with irreversible inhibitor, i.e. organophosphorus compounds is carried out using a mixture of acetylcholine and pyridine-2-aldoxime methiodide (PAM). The detection limits for the nicotine and fluoride ion are found to be 10−5M whereas for paraoxon, methyl parathion and malathion are found to be 10−9 M and 10−10 M. 相似文献
997.
A new sensitive method for qualitative and quantitative assay of neomycin phosphotransferase in crude cell extracts 总被引:57,自引:0,他引:57
A general method is described for the detection and quantification of low amounts of neomycin phosphotransferase in crude cell extracts. The assay is based on the electrophoretic separation of the enzyme from other interfering proteins and detection of its enzymatic activity by in situ phosphorylation of the antibiotic kanamycin. Both kanamycin and [γ32P]ATP acting as substrates are embedded in an agarose gel placed on the polyacrylamide gel containing the separated proteins. After the enzymatic reaction, the phosphorylated kanamycin is transferred to P81 phosphocellulose ion exchange paper and the radiolabeled kanamycin is visualised by autoradiography. With this method 1 ng of active enzyme can easily be detected. Both prokaryotic and eukaryotic cell extracts can be examined, and changes in the size of enzymatically active proteins can be determined. 相似文献
998.
Aims: To establish a multiplex PCR method for simultaneous and rapid detection of Spiroplasma eriocheiris and white spot syndrome virus (WSSV) in Procambarus clarkii with recommendations for application to other crustacea. Methods and Results: Three primer sets were mixed at a ratio of 1 : 3 : 1 to amplify specific fragments of the S. eriocheiris, WSSV, P. clarkii crayfish (control organism) genomes, respectively. S. eriocheiris and WSSV were used to challenge the susceptible crustacea in the experimental groups. Total DNA of the samples was purified and detected by multiplex PCR. The PCR‐amplified products produced four groups of results as follows. One fragment of 1195 bp, amplified by the primer set ITS‐crayfish/28S‐crayfish, served as an internal control, showed no pathogen detection, thus confirming the specificity of our positive tests. Two groups represented by: (i) samples challenged by S. eriocheiris alone, or (ii) challenged by WSSV alone, yielded two fragments each; i.e. those from S. eriocheiris (271 bp) plus the internal control and those from WSSV (530 bp) plus the internal control. Finally, for the fourth group, in cases of double challenged treatments, all three amplified products were detected simultaneously. Conclusions: Simultaneous and rapid detection of two pathogens in P. clarkii is important to maintain productive and healthy crayfish in aquaculture. The direct detection of S. eriocheiris and WSSV from P. clarkii is practicable with multiplex PCR. Significance and Impact of the Study: This study shows that the two pathogens are simultaneously and rapidly detected in P. clarkii by multiplex PCR, thus increasing the efficiency of pathogen detection. 相似文献
999.
DAVID GOLDBERG 《World psychiatry》2010,9(1):16-20
Depression and chronic physical illness are in reciprocal relationship
with one another: not only do many chronic illnesses cause higher rates of
depression, but depression has been shown to antedate some chronic physical
illnesses. Depression associated with physical illness is less well detected
than depression occurring on its own, and various ways of improving both the
detection and treatment of depression accompanying physical illness are described.
This paper is in four parts, the first dealing with the evidence for depression
having a special relationship with physical disorders, the second dealing
with detection of depression in physically ill patients, the third with the
treatment of depression, and the fourth describing the advantages of treating
depression among physically ill patients. 相似文献
1000.
Aims: A rapid real‐time PCR‐based method for the detection of Listeria monocytogenes was applied to the examination of 44 Quargel cheese samples from a recent outbreak in Austria and compared to the standard method according to ISO‐16140. Methods and Results: The combined enrichment/real‐time PCR method amplifying the prfA locus was performed according to [Rossmanith et al. (2006) Res Microbiol, 157, 763–771]. Qualitative and quantitative examination of the samples was performed according to the standard method ISO‐11290. Comparison of the combined enrichment/real‐time PCR method with ISO‐11290 resulted in 100% relative accuracy, 100% relative sensitivity and 100% relative specificity. Conclusions: A previously published study describing the validation of the method, including samples after storage at ?80°C, resulted in lower performance values. In contrast, the samples were stored at +4°C in this study. The results of this study indicate an effect of storage, thus masking the true performance of the method. Significance and Impact of the Study: The results of this study are discussed together with the previously published data to demonstrate the excellent qualities of this rapid (≤30 h) method when applied to fresh specimens stored at +4°C. 相似文献