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21.
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   
22.
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   
23.
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   
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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   
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This paper deals with H control problem for nonlinear conformable fractional order systems. The authors first derive new sufficient condition for exponential stability of nonlinear conformable fractional order systems based on Lyapunov-like function method for conformable fractional order systems and linear matrix inequalities(LMIs) approach. Then, by introducing a new concepts of H control problem for nonlinear conformable fractional order systems, the authors study H performance analysis and H state feedback controller design problems for the considered systems. In terms of LMIs, a sufficient condition is proposed to ensure the nonlinear conformable fractional order systems are not only exponentially stable, but also satisfy H performance γ. An explicit expression for state feedback controllers is also designed to make the closed-loop system is exponentially stable with H_∞performance γ. Finally, numerical examples are given to illustrate the validity and effectiveness of the proposed results.  相似文献   
29.
Many complex networks exist to facilitate the transport of material or information. In this capacity, the authors are often concerned with the continued flow of material or information when a fraction of the links in the complex network is disrupted. In other words, the authors are interested in the robustness of the complex network. In this paper, the authors survey measures of robustness like the average path length, the average clustering coefficient, the global efficiency, the size of largest cluster and use these to analyze the robustness of the bus network in Hanoi, Vietnam. The authors find that the bus network is robust against random failure but sensitive to targeted attack, in agreement with its scale-free character. By examining sharp drops in the average path length within the largest cluster of the Hanoi bus network under successive targeted attack, the authors identify five nodes whose loss lead to the fragmentation of the network into five or six disconnected clusters. These isolated clusters represent geographically the Central, Western, Southern, and Northwestern districts of Hanoi. Special considerations must therefore be given to these five nodes when planners wish to expand the bus network, or make it more robust.  相似文献   
30.
The presence of silver ions (Ag(I)) in wastewater has a detrimental effect on living organisms. Removal of soluble silver, especially at low concentrations, is challenging. This paper presents the use of β-MnO2 particles as a photocatalyst to remove Ag(I) ions selectively from aqueous solution at various pH levels. Inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffraction (XRD), field emission electron microscope (FESEM), transmission electron microscopy (TEM), and X-ray photoelectron microscopy (XPS) were employed to determine the removal efficiency and to characterize the deposition of silver onto the surface of β-MnO2 particles. The optimum pH for the removal of Ag(I) ions was at pH 4 with 99% removal efficiency under 1 h of visible light irradiation. This phenomenon can be attributed to the electrostatic attraction between β-MnO2 particles and Ag(I) ions as well as the suppression of electron–hole recombination in the presence of H+ ions.  相似文献   
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