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Jayapal Subramaniam Kalimuthu Kovendan Palanisamy Mahesh Kumar Kadarkarai Murugan William Walton 《Saudi Journal of Biological Sciences》2012,19(4):503-509
The bio-efficacy of Aloe vera leaf extract and bacterial insecticide, Bacillus sphaericus larvicidal activity was assessed against the first to fourth instars larvae of Aedes aegypti, under the laboratory conditions. The plant material was shade dried at room temperature and powdered coarsely. A. vera and B. sphaericus show varied degrees of larvicidal activity against various instars larvae of A. aegypti. The LC50 of A. vera against the first to fourth instars larvae were 162.74, 201.43, 253.30 and 300.05 ppm and the LC90 442.98, 518.86, 563.18 and 612.96 ppm, respectively. B. sphaericus against the first to fourth instars larvae the LC50 values were 68.21, 79.13, 93.48, and 107.05 ppm and the LC90 values 149.15, 164.67, 183.84, and 201.09 ppm, respectively. However, the combined treatment of A. vera + B. sphaericus (1:2) material shows highest larvicidal activity of the LC50 values 54.80, 63.11, 74.66 and 95.10 ppm; The LC90 values of 145.29, 160.14, 179.74 and 209.98 ppm, against A. aegypti in all the tested concentrations than the individuals and clearly established that there is a substantial amount of synergist act. The present investigation clearly exhibits that both A. vera and B. sphaericus materials could serve as a potential larvicidal agent. Since, A. aegypti is a container breeder vector mosquito this user and eco-friendly and low-cost vector control strategy could be a viable solution to the existing dengue disease burden. Therefore, this study provides first report on the mosquito larvicidal activity the combined effect of A. vera leaf extract and B. sphaericus against as target species of A. aegypti. 相似文献
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Four clinical cases are presented that represent our initial experience with a new fasciocutaneous free-flap unit. The territory of this flap incorporates the skin, fat, and fascia of the posterior calf region. Its design is based on the principle of the fasciocutaneous flap. Anatomic studies confirm that the blood supply to this flap is derived from a descending subfascial branch of the popliteal artery. The flap is well endowed with cutaneous sensory nerves, making it a potential neurosensory free flap. Our technique of flap design and elevation is presented, and potential advantages and disadvantages of this flap are discussed. 相似文献
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Neural correlates of behavioral gap detection in the inferior colliculus of the young CBA mouse 总被引:6,自引:0,他引:6
J. P. Walton R. D. Frisina J. R. Ison W. E. O'Neill 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,181(2):161-176
The gap detection paradigm is frequently used in psychoacoustics to characterize the temporal acuity of the auditory system.
Neural responses to silent gaps embedded in white-noise carriers, were obtained from mouse inferior colliculus (IC) neurons
and the results compared to behavioral estimates of gap detection. Neural correlates of gap detection were obtained from 78
single neurons located in the central nucleus of the IC. Minimal gap thresholds (MGTs) were computed from single-unit gap
functions and were found to be comparable, 1–2 ms, to the behavioral gap threshold (2 ms). There was no difference in MGTs
for units in which both carrier intensities were collected. Single unit responses were classified based on temporal discharge
patterns to steady-state noise bursts. Onset and primary-like units had the shortest mean MGTs (2.0 ms), followed by sustained
units (4.0 ms) and phasic-off units (4.2 ms). The longest MGTs were obtained for inhibitory neurons (xˉ = 14 ms). Finally,
the time-course of behavioral and neurophysiological gap functions were found to be in good agreement. The results of the
present study indicate the neural code necessary for behavioral gap detection is present in the temporal discharge patterns
of the majority of IC neurons.
Accepted: 6 February 1997 相似文献
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The N-(1-deoxy-D-mannitol-1-yl) and N-(1-deoxy-D-glucitol-1-yl) derivatives of L-valine, L-alanine, L-threonine, and L-leucine were prepared by reductive amination of D-mannose and D-glucose with the appropriate amino acids, in the presence of sodium cyanoborohydride. N epsilon-(1-Deoxy-D-mannitol-1-yl)- and N epsilon-(1-deoxy-D-glucitol-1-yl)-L-lysine were prepared by similar reactions of hexoses with N alpha-tert-butoxycarbonyl and N alpha-benzyloxycarbonyl-L-lysine, followed by removal of the protecting groups. The structures were confirmed by 1H-n.m.r. spectroscopy, which showed that each compound was completely free of its C-2 epimer. The synthetic compounds may be used as reference compounds for the identification of N-(1-deoxyhexitol-1-yl)amino acids formed when N-(1-deoxy-D-fructose-1-yl) groups of nonenzymically glycosylated proteins, of the hemoglobin A1c type, are reduced with sodium borohydride, and the protein is subjected to acid-catalyzed hydrolysis. 相似文献