414 resultados para (cmbsf) SZ


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Bats are an important component of mammalian biodiversity and fill such a wide array of ecological niches that they may offer an important multisensory bioindicator role in assessing ecosystem health. There is a need to monitor population trends of bats for their own sake because many populations face numerous environmental threats related to climate change, habitat loss, fragmentation, hunting, and emerging diseases. To be able to establish bat ultrasonic biodiversity trends as a reliable indicator, it is important to standardize monitoring protocols, data management, and analyses. This chapter discusses the main issues to be considered in developing a bat ultrasonic indicator. It focuses on the results from indicator bats program (iBats), a system for the global acoustic monitoring of bats, in Eastern Europe. Finally, the chapter reviews the strengths and weaknesses of the Program and considers the opportunities and threats that it may face in the future.

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Tämä pro gradu -tutkielma vertailee korpuksen avulla erisnimien kvantitatiivista jakautumista luokkiin kahdessa saksalaisessa verkkolehdessä. Työn tavoitteena on selvittää, kuinka erisnimiä voidaan luokitella ja mitä eroja niiden avulla on havaittavissa lehtien raportoinnissa. Laajempana kehyksenä toimii kysymys siitä, voidaanko erisnimiä hyödyntäen hahmottaa lehtien sisältöjä. Korpus on kerätty Frankfurter Allgemeine Zeitungin ja Süddeutsche Zeitungin verkkolehtien http: //www.faz.net (FAZ) ja http://www.sueddeutsche.de (SZ) artikkeleista ajalta 2.11.2004-8.11.2004. Valitut sivustot edustavat Saksan arvostetuimpien päivittäisten, koko maan kattavien sanomaleh- tien verkkojulkaisuja. Näistä FAZ:ia pidetään konservatiivisena ja SZ:ia liberaalina lehtenä. Kumpikin korpus käsittelee USA:n presidentinvaaleja syksyllä 2004 ja sisältää hieman alle 30 000 sanaa noin 40 lehtiartikkelista. Aihesidonnaisen korpuksen valinta perustuu erityisesti siihen, että tutkimuksen päämääränä on saada erisnimien avulla selville, miltä osin FAZ ja SZ eroavat toisistaan käsitellessään samaa aihetta. Teoriaosassa käydään läpi saksalaisten verkkolehtien taustaa, työhön liittyviä tekstilingvistisiä teo- rioita sekä erisnimien erikoispiirteitä. Siinä käsitellään myös kolmea aiempaa, saksankielisen eris- nimitutkimuksen luokittelua ja yhtä englanninkielistä, kieliteknologian luokittelua. Näissä havaitut puutteet motivoivat yhdistelemään ja muuttamaan olemassa olevia luokitteluja tätä työtä varten. Uusi luokittelu sisältää neljä yläluokkaa (olentojen, maantieteelliset, instituutioden ja asioiden ni- met), jotka kaikki kattavat kahdesta yhdeksään alaluokkaa. Kummankin korpuksen erisnimet luo- kitellaan tämän perusteella. Kvantitatiivinen analyysi keskittyy ylä- ja alaluokkien vertailuun lehtien välillä. Lisäksi se kattaa sekä kummankin aineiston että pääluokkien frekventimpien sanojen tarkastelun. Vaikka FAZ ja SZ käyttivätkin pääosin samoja erisnimiä raportoinnissaan, voidaan lehtien välillä osoittaa selkeitä eroja alaluokkien kohdalla ja vähäisiä eroja erisnimien jakautumisessa yläluokkiin. chi2 -testin näytti kuitenkin, että erisnimien jakautuminen yläluokkiin on lehtisidonnaista. Siksi voidaan väittää, että muun muassa valittu media vaikuttaa erisnimivalintoihin. Erisnimien frekvenssit antavat ymmärtää, että SZ raportoisi monipuolisemmin kuin FAZ, joka käyttää erisnimiä keskitetymmin. SZ:in aineiston erisnimiä yhdistää eurooppalainen näkökulma vaaleihin, kun taas FAZ pyrkii tuomaan esille tapahtumia USA:n eri osavaltioissa. Niin lehdissä mainitut henkilöiden kuin instituutioden nimet tukevat tätä väitetettä. SZ korostaa maantieteellisesti kaupunkien merkitystä, FAZ osavaltioiden. Saadut tulokset osoittavat, että tämänkaltaisen erisnimitutkimuksen soveltaminen lehtiteksteihin on mahdollista. Luokitellut erisnimet heijastavat osittain käsiteltyjen aineistojen sisältöä ja paljastavat raportoinnin painopisteistä.

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As for other complex diseases, linkage analyses of schizophrenia (SZ) have produced evidence for numerous chromosomal regions, with inconsistent results reported across studies. The presence of locus heterogeneity appears likely and may reduce the power of linkage analyses if homogeneity is assumed. In addition, when multiple heterogeneous datasets are pooled, inter-sample variation in the proportion of linked families (alpha) may diminish the power of the pooled sample to detect susceptibility loci, in spite of the larger sample size obtained. We compare the significance of linkage findings obtained using allele-sharing LOD scores (LOD(exp))-which assume homogeneity-and heterogeneity LOD scores (HLOD) in European American and African American NIMH SZ families. We also pool these two samples and evaluate the relative power of the LOD(exp) and two different heterogeneity statistics. One of these (HLOD-P) estimates the heterogeneity parameter alpha only in aggregate data, while the second (HLOD-S) determines alpha separately for each sample. In separate and combined data, we show consistently improved performance of HLOD scores over LOD(exp). Notably, genome-wide significant evidence for linkage is obtained at chromosome 10p in the European American sample using a recessive HLOD score. When the two samples are combined, linkage at the 10p locus also achieves genome-wide significance under HLOD-S, but not HLOD-P. Using HLOD-S, improved evidence for linkage was also obtained for a previously reported region on chromosome 15q. In linkage analyses of complex disease, power may be maximised by routinely modelling locus heterogeneity within individual datasets, even when multiple datasets are combined to form larger samples.

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Several lines of evidence have implicated the catechol-O-methyltransferase (COMT) gene as a candidate for schizophrenia (SZ) susceptibility, not only because it encodes a key dopamine catabolic enzyme but also because it maps to the velocardiofacial syndrome region of chromosome 22q11 which has long been associated with SZ predisposition. The interest in COMT as a candidate SZ risk factor has led to numerous case-control and family-based studies, with the majority placing emphasis on examining a functional Val/Met polymorphism within this enzyme. Unfortunately, these studies have continually produced conflicting results. To assess the genetic contribution of other COMT variants to SZ susceptibility, we investigated three single-nucleotide polymorphisms (SNPs) (rs737865, rs4633, rs165599) in addition to the Val/Met variant (rs4680) in a highly selected sample of Australian Caucasian families containing 107 patients with SZ. The Val/Met and rs4633 variants showed nominally significant associations with SZ (P<0.05), although neither of the individual SNPs remained significant after adjusting for multiple testing (most significant P=0.1174). However, haplotype analyses showed strong evidence of an association; the most significant being the three-marker haplotype rs737865-rs4680-rs165599 (global P=0.0022), which spans more than 26 kb. Importantly, conditional analyses indicated the presence of two separate and interacting effects within this haplotype, irrespective of gender. In addition, our results indicate the Val/Met polymorphism is not disease-causing and is simply in strong linkage disequilibrium with a causative effect, which interacts with another as yet unidentified variant approximately 20 kb away. These results may help explain the inconsistent results reported on the Val/Met polymorphism and have important implications for future investigations into the role of COMT in SZ susceptibility.

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A spin one Ising system with biquadratic exchange, is investigated, using Green's function technique in random phase approximation (RPA). Transition temperature Tc and <(Sz)2> at Tc, are found to increase with biquadratic exchange parameter α for sc, bcc and fcc lattices. The variation of <(Sz)2> at Tc with α is found to be the same for the above lattices.

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1,1,3-Trimethyl-2-thioxo-1,2-dihydronaphthale(1n)e adds to electron-rich olefins upon excitation to either Sz (PP*) or Sl (ns*) states. Excitation to S2 level resulted in the same mixture of products, namely thietane and 1,4-dithiane, as on excitation to S1 level. Addition occurs to the thiocarbonyl function and not to the carbon-carbon double bond. The addition is site-specific, and the formation of thietane is regiospecific. The ratio of thietane to 1,4-dithiane in the product mixture is dependent on the concentration of the thioenone. The addition is suggested to originate from the lowest triplet state (Tl) and involves diradical intermediates.

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A spin one XY ferromagnet with uniaxial anisotropy has been investigated, using Green's function technique in random phase approximation (RPA). The Green functions associated with the anisotropy energy are treated without decoupling. A set of coupled equations have been obtained to find the critical temperature Tc and left angle bracket(SZ)2right-pointing angle bracket at Tc as function of the uniaxial anisotropy parameter D. Tc and left angle bracket(SZ)2right-pointing angle bracket at Tc are found to increase with D. The results are compared with the earlier results obtained in the Narath type of RPA.

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The characteristic function for a contraction is a classical complete unitary invariant devised by Sz.-Nagy and Foias. Just as a contraction is related to the Szego kernel k(S) (z, w) = (1 - z (w) over tilde)(-1) for |z|, |w| < 1, by means of (1/k(S))(T,T*) >= 0, we consider an arbitrary open connected domain Omega in C-n, a complete Pick kernel k on Omega and a tuple T = (T-1, ..., T-n) of commuting bounded operators on a complex separable Hilbert space H such that (1/k)(T,T*) >= 0. For a complete Pick kernel the 1/k functional calculus makes sense in a beautiful way. It turns out that the model theory works very well and a characteristic function can be associated with T. Moreover, the characteristic function is then a complete unitary invariant for a suitable class of tuples T.

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Extensive molecular dynamics simulations have been carried out to calculate the orientational correlation functions Cl(t), G(t) = [4n/(21 + l)]Ci=-l (Y*lm(sZ(0)) Ylm(Q(t))) (where Y,,(Q) are the spherical harmonics) of point dipoles in a cubic lattice. The decay of Cl(t) is found to be strikingly different from higher l-correlation functions-the latter do not exhibit diffusive dynamics even in the long time. Both the cumulant expansion expression of Lynden-Bell and the conventional memory function equation provide very good description of the Cl(t) in the short time but fail to reproduce the observed slow, long time decay of c1 (t) .

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The characteristic function for a contraction is a classical complete unitary invariant devised by Sz.-Nagy and Foias. Just as a contraction is related to the Szego kernel k(S)(z, w) = ( 1 - z(w)over bar)- 1 for |z|, |w| < 1, by means of (1/k(S))( T, T *) = 0, we consider an arbitrary open connected domain Omega in C(n), a kernel k on Omega so that 1/k is a polynomial and a tuple T = (T(1), T(2), ... , T(n)) of commuting bounded operators on a complex separable Hilbert spaceHsuch that (1/k)( T, T *) >= 0. Under some standard assumptions on k, it turns out that whether a characteristic function can be associated with T or not depends not only on T, but also on the kernel k. We give a necessary and sufficient condition. When this condition is satisfied, a functional model can be constructed. Moreover, the characteristic function then is a complete unitary invariant for a suitable class of tuples T.

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在多年地基研究的基础上,作为载人航天工程应用系统的有效载荷,在我国“神舟”四号飞船返回舱在轨飞行期间进行了大Marangoni数(Ma)液滴热毛细迁移空间微重力实验.实验中FC-75液和.5cst硅油分别为滴相和连续相实验流体介质,研究了在稳定、长时间的微重力环境中,不同温度梯度条件下液滴热毛细迁移的现象及特征.Marangoni数到达5500,很大地扩展了过去液滴热毛细迁移实验的Ma参数范围.实验结果表明,大Ma数液滴热毛细迁移特征规律复杂,迁移速度与YGB模型线性预测有明显的差别.文章介绍了液滴热毛细迁移研究进展,给出了此次空间实验的一些主要结果.讨论了大Ma液滴热毛细迁移的特征,并对自行研制的空间实验设备、实验过程进行了简要介绍.

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Under optimized operating parameters, a hard and wear resistant ( Ti,Al)N film is prepared on a normalized T8 carbon tool steel substrate by using pulsed high energy density plasma technique. Microstructure and composition of the film are analysed by x-ray diffraction, x-ray photoelectron spectroscopy, Auger electron spectroscopy and scanning electron microscopy. Hardness profile and tribological properties of the film are tested with nano-indenter and ring-on-ring wear tester, respectively. The tested results show that the microstructure of the film is dense and uniform and is mainly composed of ( Ti,Al)N and AlN hard phases. A wide transition interface exists between the film and the normalized T8 carbon tool steel substrate. Thickness of the film is about 1000 nm and mean hardness value of the film is about 26GPa. Under dry sliding wear test conditions, relative wear resistance of the ( Ti,Al)N film is approximately 9 times higher than that of the hardened T8 carbon tool steel reference sample. Meanwhile, the ( Ti,Al)N film has low and stable friction coefficient compared with the hardened T8 carbon tool steel reference sample.