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71.
Delous M Baala L Salomon R Laclef C Vierkotten J Tory K Golzio C Lacoste T Besse L Ozilou C Moutkine I Hellman NE Anselme I Silbermann F Vesque C Gerhardt C Rattenberry E Wolf MT Gubler MC Martinovic J Encha-Razavi F Boddaert N Gonzales M Macher MA Nivet H Champion G Berthélémé JP Niaudet P McDonald F Hildebrandt F Johnson CA Vekemans M Antignac C Rüther U Schneider-Maunoury S Attié-Bitach T Saunier S 《Nature genetics》2007,39(7):875-881
Cerebello-oculo-renal syndrome (CORS), also called Joubert syndrome type B, and Meckel (MKS) syndrome belong to the group of developmental autosomal recessive disorders that are associated with primary cilium dysfunction. Using SNP mapping, we identified missense and truncating mutations in RPGRIP1L (KIAA1005) in both CORS and MKS, and we show that inactivation of the mouse ortholog Rpgrip1l (Ftm) recapitulates the cerebral, renal and hepatic defects of CORS and MKS. In addition, we show that RPGRIP1L colocalizes at the basal body and centrosomes with the protein products of both NPHP6 and NPHP4, known genes associated with MKS, CORS and nephronophthisis (a related renal disorder and ciliopathy). In addition, the RPGRIP1L missense mutations found in CORS individuals diminishes the interaction between RPGRIP1L and nephrocystin-4. Our findings show that mutations in RPGRIP1L can cause the multiorgan phenotypic abnormalities found in CORS or MKS, which therefore represent a continuum of the same underlying disorder. 相似文献
72.
de Vries W Solberg S Dobbertin M Sterba H Laubhahn D Reinds GJ Nabuurs GJ Gundersen P Sutton MA 《Nature》2008,451(7180):E1-3; discussion E3-4
Magnani et al. present a very strong correlation between mean lifetime net ecosystem production (NEP, defined as the net rate of carbon (C) accumulation in ecosystems) and wet nitrogen (N) deposition. For their data in the range 4.9-9.8 kg N ha(-1) yr(-1), on which the correlation largely depends, the response is approximately 725 kg C per kg N in wet deposition. According to the authors, the maximum N wet deposition level of 9.8 kg N ha(-1) yr(-1) is equivalent to a total deposition of 15 kg N ha(-1 )yr(-1), implying a net sequestration near 470 kg C per kg N of total deposition. We question the ecological plausibility of the relationship and show, from a multi-factor analysis of European forest measurements, how interactions with site productivity and environment imply a much smaller NEP response to N deposition. 相似文献
73.
Wayne A. Hubert 《西北部美国博物学家》2011,48(3)
Collections of crayfish by Wyoming Game and Fish Department biologists and University of Wyoming staff in 1985-1987 included five species: Pacifastacus gambelii , the only species found in the Snake River and Bear River drainages of western Wyoming; Orconectes neglectus neglectus , collected from one reservoir in the South Platte River drainage in southeastern Wyoming (its first reported occurrence in the state); O. immunis and O. virilis ,widespread east of the Continental Divide and in the Green River drainage of southwestern Wyoming; and Cambarus Diogenes Diogenes , collected from a tributary of the North Platte River in eastern Wyoming. 相似文献
74.
Mukha I Roeckl E Batist L Blazhev A Döring J Grawe H Grigorenko L Huyse M Janas Z Kirchner R La Commara M Mazzocchi C Tabor SL Van Duppen P 《Nature》2006,439(7074):298-302
The stability and spontaneous decay of naturally occurring atomic nuclei have been much studied ever since Becquerel discovered natural radioactivity in 1896. In 1960, proton-rich nuclei with an odd or an even atomic number Z were predicted to decay through one- and two-proton radioactivity, respectively. The experimental observation of one-proton radioactivity was first reported in 1982, and two-proton radioactivity has now also been detected by experimentally studying the decay properties of 45Fe (refs 3, 4) and 54Zn (ref. 5). Here we report proton-proton correlations observed during the radioactive decay of a spinning long-lived state of the lightest known isotope of silver, 94Ag, which is known to undergo one-proton decay. We infer from these correlations that the long-lived state must also decay through simultaneous two-proton emission, making 94Ag the first nucleus to exhibit one- as well as two-proton radioactivity. We attribute the two-proton emission behaviour and the unexpectedly large probability for this decay mechanism to a very large deformation of the parent nucleus into a prolate (cigar-like) shape, which facilitates emission of protons either from the same or from opposite ends of the 'cigar'. 相似文献
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78.
L2
-norm: (1)
dynamic programming; (2) an iterative quadratic assignment improvement
heuristic; (3) the Guttman update strategy as modified by Pliner's technique
of smoothing; (4) a nonlinear programming reformulation by Lau, Leung, and
Tse. The methods are all implemented through (freely downloadable) MATLAB
m-files; their use is illustrated by a common data set carried throughout. For
the computationally intensive dynamic programming formulation that can a
globally optimal solution, several possible computational improvements are
discussed and evaluated using (a) a transformation of a given m-function with
the MATLAB Compiler into C code and compiling the latter; (b) rewriting an
m-function and a mandatory MATLAB gateway directly in Fortran and compiling
into a MATLAB callable file; (c) comparisons of the acceleration of raw
m-files implemented under the most recent release of MATLAB Version 6.5 (and compared to the absence of such
acceleration under the previous MATLAB Version 6.1). Finally, and in contrast
to the combinatorial optimization task of identifying a best unidimensional
scaling for a given proximity matrix, an approach is given for the
confirmatory fitting of a given unidimensional scaling based only on a fixed
object ordering, and to nonmetric unidensional scaling that incorporates an
additional optimal monotonic transformation of the proximities. 相似文献
79.
The additive clustering approach is applied to the problem of two-mode clustering and compared with the recent error-variance
approach of Eckes and Orlik (1993). Although the schemes of the computational algorithms look very similar in both of the
approaches, the additive clustering has been shown to have several advantages. Specifically, two technical limitations of
the error-variance approach (see Eckes and Orlik 1993, p. 71) have been overcome in the framework of the additive clustering.
The research was supported by the Office of Naval Research under grant number N0014-93-1-0222 to Rutgers University. The authors
are indebted both to Fionn Murtagh, who served as Acting Editor, and to anonymous Referees for thoughtful and constructive
reviews. 相似文献
80.
Summary The addition of serum or Tween 80 to a synthetic culture medium for tubercle bacilli considerably reduces the inhibitory effect of various substances with the exception of streptomycin and promin, whose effect is less weakened, and which retain their tuberculostatic action to a considerable degree. The antagonistic effect of Tween 80 is still recognizable in small dilutions where its diffusion effect can no longer be observed.
Die Arbeit wurde durch einen Arbeitsbeschaffungskredit des Bundes ermöglicht, für dessen Gewährung wir auch an dieser Stelle danken. 相似文献
Die Arbeit wurde durch einen Arbeitsbeschaffungskredit des Bundes ermöglicht, für dessen Gewährung wir auch an dieser Stelle danken. 相似文献