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11.
Summary Muscimol induced in rats a recall deficit which possibly results from a dissociation of learning. In one out of the 2 experimental conditions studied, a cross dissociation of learning was found between diazepam and muscimol.This work was supported by a grant of INSERM (ATP 39-76-71).  相似文献   
12.
Circumstellar accretion disks transfer matter from molecular clouds to young stars and to the sites of planet formation. The disks observed around pre-main-sequence stars have properties consistent with those expected for the pre-solar nebula from which our own Solar System formed 4.5 Gyr ago. But the 'debris' disks that encircle more than 15% of nearby main-sequence stars appear to have very small amounts of gas, based on observations of the tracer molecule carbon monoxide: these observations have yielded gas/dust ratios much less than 0.1, whereas the interstellar value is about 100 (ref. 9). Here we report observations of the lowest rotational transitions of molecular hydrogen (H2) that reveal large quantities of gas in the debris disks around the stars beta Pictoris, 49 Ceti and HD135344. The gas masses calculated from the data are several hundreds to a thousand times greater than those estimated from the CO observations, and yield gas/dust ratios of the same order as the interstellar value.  相似文献   
13.
Under new assumptions, this paper obtains some extended versions of Ky Fan type inequality for a family of C-continuous set-valued mappings in the setting of topological semilattices. The obtained results are new and different from the corresponding known results in the literature. Some special cases of the main result are also discussed. Some examples are given to illustrate the results.  相似文献   
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15.
Brookite TiO_2 nanoparticles were synthesized by hydrothermal method and characterized by X-ray powder diffraction(XRD), diffuse reflectance UV–Visible spectroscopy(DRUV), and scanning electron microscopy(SEM). The obtained particles were spherical in shape with the diameter of about ~10 nm under the hydrothermal temperature of 175 °C. The photocatalytic performance of brookite was investigated in the photodegradation of dyes(rhodamine B and rose bengal) under UV-A radiation by low-power lamp. The activity of brookite and the photodegradation efficiency of dyes were estimated using a UV–Visible spectrophotometer and a total organic carbon(TOC) analyzer. Compared to anatase and rutile prepared by the similar synthesis procedure, brookite is highly active in terms of decolourization, aromatic ring opening, and mineralization.  相似文献   
16.
Muscimol induced in rats a recall deficit which possibly results from a dissociation of learning. In one out of the 2 experimental conditions studied, a cross dissociation of learning was found between diazepam and muscimol.  相似文献   
17.
ABSTRACT

A new rhacophorid species is described from Vietnam on the basis of nine specimens collected in Quan Ba District, Ha Giang Province, northeastern Vietnam. The new species is morphologically similar to Zhangixalus pinglongensis, Z. dorsoviridis, and Z. nigropunctatus, however, it differs from the latter by having the flank cream with large black blotches on axilla and groin. The genetic distance between the new species and Zhangixalus pinglongensis, Z. dorsoviridis and Z. nigropunctatus is >3.57% (16S mtDNA gene fragment). Zhangixalus jodiae sp. nov. can be distinguished from all other species of Zhangixalus and other small rhacophorid species from Southeast Asia by a combination of the following characters: size small (SVL 36.1–39.8 mm in males); head as long as wide; vomerine teeth present; dorsal surface of head and body green without spots; axilla cream with large black blotches, groin and front-rear parts of the thigh, ventral surface of tibia black with orange blotches; lower jaw region greyish, chest and belly cream.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:89597718-024F-4FFC-B0AE-2005F12CF66C  相似文献   
18.
ABSTRACT

Species boundaries within the red-eyed Leptobrachium of southern Indochina have been uncertain. Leptobrachium pullum and L. mouhoti from upper and lower elevations, respectively, of the Langbian Plateau of southern Vietnam and eastern Cambodia differ in body size but have relatively low interspecific mitochondrial DNA divergence, leading to speculation that these might represent a single species with an elevational cline in body size. The recent discovery of an allopatric high-elevation population of red-eyed Leptobrachium on the Kon Tum Plateau (= Central Highlands) of north-eastern Cambodia and central Vietnam has been referred to both species, and to a putatively undescribed species. We examine variation in morphology of adults and tadpoles, mitochondrial DNA, 11 nuclear genes and advertisement calls, and show corroborating lines of evidence for the existence of three species of red-eyed Leptobrachium in southern Indochina. Although the three species are reciprocally monophyletic in mitochondrial DNA, their shallow mitochondrial DNA divergences are not mirrored by morphology, advertisement calls, or – in part – nuclear DNA, and probably reflect past mitochondrial introgression rather than recent speciation. The Central Highlands taxon is described herein as a new species.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:CE6650AF-D9FB-40F4-8A2E-9B4E23AAC205  相似文献   
19.
This paper obtains sufficient optimality conditions for a nonlinear nondifferentiable multiobjective semi-infinite programming problem involving generalized(C,α,ρ,d)-convex functions.The authors formulate Mond-Weir-type dual model for the nonlinear nondifferentiable multiobjective semiinfinite programming problem and establish weak,strong and strict converse duality theorems relating the primal and the dual problems.  相似文献   
20.
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