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991.
Lee JC Tsai LC Huang MT Jhuang JA Yao CT Chin SC Wang LC Linacre A Hsieh HM 《Electrophoresis》2008,29(11):2413-2418
We report a DNA-based test that can be applied to any avian species so that the amplicon can be used in species identification. The need for the test arose from the requirement to enforce the Wildlife Conservation Act in Taiwan where over 150 avian species are protected. It is difficult to enforce the law if no gross morphology is present and hence there is a requirement to develop a DNA test. This study uses a novel strategy for avian species identification by the cytochrome b gene where a series of primer pairs producing amplicons of decreasing size was designed. The test is designed to produce the largest possible amplicon based upon the quality of the DNA in the sample. A total of 331 avian samples were tested representing 40 species. Sequencing of the amplicons revealed limited intraspecies variation and that no DNA sequence was shared by samples from two different avian species. The closest genetic distance among the 40 species was 0.059 which was between Lonchura punctulata and Estrilda melpoda based upon data from the smallest amplicon. A DNA databank including 138 sequence types from 331 samples tested, representing 40 different species, was constructed in this study. A blind test was used to determine the value for this system for forensic applications that successfully identified the species. 相似文献
992.
A multiplex assay to identify 18 European mammal species from mixtures using the mitochondrial cytochrome b gene 总被引:5,自引:0,他引:5
A novel species-specific multiplex to identify 18 common European mammalian species (badger, cat, cow, dog, donkey, fox, goat, guinea pig, harvest mouse, hedgehog, horse, house mouse, human, pig, rabbit, rat, red deer and sheep), many of which are often associated with forensic investigations, has been developed. The assay is based on the mitochondrial cytochrome b gene, which is commonly used in species identification and phylogeny studies. Areas of homology and variation were identified and were used to create universal and species-specific primers. The species-specific primers were designed such that they will only react with the species for which they were designed. Two primer sets were designed for each species making the test self-confirmatory. All primer sets produced the expected results. The multiplex was balanced at template concentration of 40 000 copies (approximately 1.36 pg). Validation was accomplished by analysing the same sample ten times to determine run variation and several samples for each species to determine between-sample variation. Twenty-eight additional mammalian species were reacted with the multiplex. The multiplex provides, for the first time, a definitive method for identification of species in a forensic context. 相似文献
993.
Paraskar AS Reddy AR Patra A Wijsboom YH Gidron O Shimon LJ Leitus G Bendikov M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(34):10639-10647
Surprisingly, despite its very high mobility in a single crystal, rubrene shows very low mobility in vacuum-sublimed or solution-processed organic thin-film transistors. We synthesized several rubrene analogues with electron-withdrawing and electron-donating substituents and found that most of the substituted rubrenes are not planar in the solid state. Moreover, we conclude (based on experimental and calculated data) that even parent rubrene is not planar in solution and in thin films. This discovery explains why high mobility is reported in rubrene single crystals, but rubrene shows very low field-effect mobility in thin films. The substituted rubrenes obtained in this work have significantly better solubility than parent rubrene and some even form films and not crystals after evaporation of the solvent. Thus, substituted rubrenes are promising materials for organic light-emitting diode (OLED) applications. 相似文献
994.
995.
996.
Chi‐Ming Che Prof. Hai‐Feng Xiang Dr. Stephen Sin‐Yin Chui Dr. Zong‐Xiang Xu V. A. L. Roy Dr. Jessie Jing Yan Wen‐Fu Fu Prof. P. T. Lai Prof. Ian D. Williams Prof. 《化学:亚洲杂志》2008,3(7):1092-1103
Organic field‐effect transistors incorporating planar π‐conjugated metal‐free macrocycles and their metal derivatives are fabricated by vacuum deposition. The crystal structures of [H2(OX)] (H2OX=etioporphyrin‐I), [Cu(OX)], [Pt(OX)], and [Pt(TBP)] (H2TBP=tetra‐(n‐butyl)porphyrin) as determined by single crystal X‐ray diffraction (XRD), reveal the absence of occluded solvent molecules. The field‐effect transistors (FETs) made from thin films of all these metal‐free macrocycles and their metal derivatives show a p‐type semiconductor behavior with a charge mobility (μ) ranging from 10?6 to 10?1 cm2 V?1 s?1. Annealing the as‐deposited Pt(OX) film leads to the formation of a polycrystalline film that exhibits excellent overall charge transport properties with a charge mobility of up to 3.2×10?1 cm2 V?1 s?1, which is the best value reported for a metalloporphyrin. Compared with their metal derivatives, the field‐effect transistors made from thin films of metal‐free macrocycles (except tetra‐(n‐propyl)porphycene) have significantly lower μ values (3.0×10?6–3.7×10?5 cm2 V?1 s?1). 相似文献
997.
We study equivalence relations and II1 factors associated with (quotients of) generalized Bernoulli actions of Kazhdan groups. Specific families of these actions are entirely classified up to isomorphism of II1 factors. This yields explicit computations of outer automorphism and fundamental groups. In particular, every finitely presented group is concretely realized as the outer automorphism group of a continuous family of non stably isomorphic II1 factors. 相似文献
998.
Emanuel Milman 《Advances in Mathematics》2008,217(6):2822-2840
In [A. Koldobsky, A functional analytic approach to intersection bodies, Geom. Funct. Anal. 10 (2000) 1507-1526], A. Koldobsky asked whether two types of generalizations of the notion of an intersection body are in fact equivalent. The structures of these two types of generalized intersection bodies have been studied by the author in [E. Milman, Generalized intersection bodies, J. Funct. Anal. 240 (2) (2006) 530-567], providing substantial evidence for a positive answer to this question. The purpose of this note is to construct a counter-example, which provides a surprising negative answer to this question in a strong sense. This implies the existence of non-trivial non-negative functions in the range of the spherical Radon transform, and the existence of non-trivial spaces which embed in Lp for certain negative values of p. 相似文献
999.
An n-ary operation Q:Σn→Σ is called an n-ary quasigroup of order |Σ| if in the relation x0=Q(x1,…,xn) knowledge of any n elements of x0,…,xn uniquely specifies the remaining one. Q is permutably reducible if Q(x1,…,xn)=P(R(xσ(1),…,xσ(k)),xσ(k+1),…,xσ(n)) where P and R are (n-k+1)-ary and k-ary quasigroups, σ is a permutation, and 1<k<n. An m-ary quasigroup S is called a retract of Q if it can be obtained from Q or one of its inverses by fixing n-m>0 arguments. We prove that if the maximum arity of a permutably irreducible retract of an n-ary quasigroup Q belongs to {3,…,n-3}, then Q is permutably reducible. 相似文献
1000.
The core of a game v on N, which is the set of additive games φ dominating v such that φ(N)=v(N), is a central notion in cooperative game theory, decision making and in combinatorics, where it is related to submodular functions, matroids and the greedy algorithm. In many cases however, the core is empty, and alternative solutions have to be found. We define the k-additive core by replacing additive games by k-additive games in the definition of the core, where k-additive games are those games whose Möbius transform vanishes for subsets of more than k elements. For a sufficiently high value of k, the k-additive core is nonempty, and is a convex closed polyhedron. Our aim is to establish results similar to the classical results of Shapley and Ichiishi on the core of convex games (corresponds to Edmonds’ theorem for the greedy algorithm), which characterize the vertices of the core. 相似文献