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201.
Samantha Bothwell Alex Kaizer Ryan Peterson Danielle Ostendorf Victoria Catenacci Julia Wrobel 《Biometrics》2023,79(3):2719-2731
“Smart”-scales are a new tool for frequent monitoring of weight change as well as weigh-in behavior. These scales give researchers the opportunity to discover patterns in the frequency that individuals weigh themselves over time, and how these patterns are associated with overall weight loss. Our motivating data come from an 18-month behavioral weight loss study of 55 adults classified as overweight or obese who were instructed to weigh themselves daily. Adherence to daily weigh-in routines produces a binary times series for each subject, indicating whether a participant weighed in on a given day. To characterize weigh-in by time-invariant patterns rather than overall adherence, we propose using hierarchical clustering with dynamic time warping (DTW). We perform an extensive simulation study to evaluate the performance of DTW compared to Euclidean and Jaccard distances to recover underlying patterns in adherence time series. In addition, we compare cluster performance using cluster validation indices (CVIs) under the single, average, complete, and Ward linkages and evaluate how internal and external CVIs compare for clustering binary time series. We apply conclusions from the simulation to cluster our real data and summarize observed weigh-in patterns. Our analysis finds that the adherence trajectory pattern is significantly associated with weight loss. 相似文献
202.
Shirley P. Tolley Gideon J. Davies Mark O'Shea Mark I. Cockett Andrew J. P. Docherty Gillian Murphy 《Proteins》1993,17(4):435-437
A nonglycosylated (N30QN78Q) form of the human tissue inhibitor of metalloproteinases, TIMP-1, has been prepared and crystallized in a form suitable for X-ray diffraction analysis. Small single crystals have been grown using sodium tartrate as a precipitant. The crystals are in space group P21, with cell dimensions a = 35.28, b = 53.95, c = 48.56, and β = 96.0°. There is a single molecule of TIMP-1 in the asymmetric unit. The crystals diffract to at least 2.3 Å resolution. Complete data have been collected to 2.9 Å and a search for heavymetal derivatives is in progress. © 1993 Wiley-Liss, Inc. 相似文献
203.
Arpana Agrawal Sarah J. Brislin Kathleen K. Bucholz Danielle Dick Ronald P. Hart Emma C. Johnson Jacquelyn Meyers Jessica Salvatore Paul Slesinger COGA Collaborators Laura Almasy Tatiana Foroud Alison Goate Victor Hesselbrock John Kramer Samuel Kuperman Alison K. Merikangas John I. Nurnberger Jay Tischfield Howard J. Edenberg Bernice Porjesz 《Genes, Brain & Behavior》2023,22(5):e12864
204.
M. Matsuda A. Kaneko M. Fukuyama T. Itoh M. Shingaki M. Inoue J.E. Moore P.G. Murphy Y. Ishida 《Journal of applied microbiology》1996,81(6):608-612
Two strains of urease-positive thermophilic Campylobacter (UPTC), CF89–12 and CF89–14, which were identified as UPTC by biochemical characterization, were found for the first time in river water in the Far East, namely, in Japan. The biochemical characteristics were identical to those of strains described previously by Bolton and colleagues. Furthermore, these two strains were positive for arylsulphatase. Consequently, it was demonstrated that UPTC may possibly be differentiated phenotypically from Campylobacter lari by the arylsulphatase test, as well as urease and nalidixic acid tests. Analysis by pulsed-field gel electrophoresis (PFGE) after digestion with Apa I, Sal I and Sma I, which were found to produce distributions of DNA fragments to be suitable for analysis of the genomic DNA from the thermophilic Campylobacter , respectively, demonstrated that these three restriction enzymes produced distributions of a relatively limited number of genomic DNA fragments and also demonstrated that the PFGE profiles obtained with the three restriction enzymes were indistinguishable between the two strains, respectively. The PFGE analysis and conventional fixed-field agarose gel electrophoresis suggested that the both genomes were approximately 1862 kb in length. Even though the two isolates of UPTC were isolated from water in different rivers in Japan, the results suggested that a single strain. as opposed to two distinct strains, was isolated. PFGE profiles after digestion with Sal I and Sma I, respectively, were also demonstrated to be distinctly different among strains isolated in Japan and previously in Europe. This is the first example of the isolation of UPTC from natural sources in countries other than those in Europe. 相似文献
205.
206.
Joanne H.E. Ross Denis J. Murphy 《The Plant journal : for cell and molecular biology》1996,9(5):625-637
A large, heterogeneous, highly expressed gene family encoding oleosin-like proteins is described in the Brassicaceae. íeven related cDNA sequences were isolated from Brassica napus anther mRNA using RACE-PCR and compared with other recently described anther-specific oleosin-like genes from B. napus. The expression patterns of four representative members of this diverse gene family were analyzed by Northern blotting and in situ hybridization. In all cases, the genes were expressed specifically in the tapetum of 3–5 mm B. napus buds, which contained microspores at the late-vacuolate and bicellular stages of development. The predicted protein products are ordered into subclasses, each of which has a characteristic C-terminal domain, containing different amino acid motifs or repeated residues. Tryphine (pollen coat) fractions from mature B. napus pollen were found to be particularly enriched in polypeptides of apparent molecular weights 32–38 kDa, plus numerous less abundant polypeptides of less than 15 kDa. The N-terminal 15–20 residues of three of these polypeptides (12, 32 and 38 kDa) were found by microsequencing to be identical to parts of the predicted amino acid sequences of three of the tapetal-expressed oleosin-like genes. This indicates the possibility of post-translational modification of these proteins resulting in a cleavage of the primary translation products in order to generate the mature tryphine polypeptides. These data imply that a large and diverse group of oleosin-like proteins is synthesized in the tapeturn of B. napus anthers and that following tapetal degradation, these proteins, possibly in modified form, then relocate to the developing microspores where they eventually constitute some of the major components of the extracellular tryphine of mature pollen grains. These proteins share a conserved 70 amino acid residue hydrophobic domain and are related structurally to the seed-specific intracellular oleosins, although their biological function may be different. 相似文献
207.
208.
A New Pressure Probe Method to Determine the Average Volumetric Elastic Modulus of Cells in Plant Tissue 总被引:1,自引:0,他引:1
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A new in vivo method was used to determine an average volumetric elastic modulus ([epsilon]ave) for nongrowing cells in plant tissue. This method requires that both the relative transpiration rate, T, of the tissue and the average turgor pressure decay rate, (dP/dt)ave, of the cells are measured after the water source is removed from the plant tissue. Then [epsilon]ave is calculated from the equation [epsilon]ave = (-dP/dt)ave/T. This method was used to determine [epsilon]ave for cortical cells in stems of pea seedlings (Pisum sativum L.). The results demonstrate that [epsilon]ave increases from virtually zero at low P (approximately 0.01MPa) to approximately 10 MPa at high P (approximately 0.5 MPa). Analyses of the results indicate that the relationship between [epsilon]ave and P can be approximated by a linear function and more accurately approximated by a saturating exponential function: [epsilon]ave = [epsilon][infinity symbol][1 - exp {-k(P - Po)}], where Po is a plateau pressure (approximately 0.01 MPa), k is a rate constant (approximately 7 per MPa), and [epsilon][infinity symbol] (approximately 10 MPa) is the hypothetical maximum value of [epsilon]ave as P -> [infinity symbol]. Solutions for the turgor pressure decay (due to transpiration) as functions of time and symplasmic water mass (after the water source is removed) are derived. 相似文献
209.
210.
Alexander A. Bachmanov Danielle R. Reed Yuro Ninomiya Masashi Inoue Michael G. Tordoff R. Arlen Price Gary K. Beauchamp 《Mammalian genome》1997,8(8):545-548
Individual variability in sucrose consumption is prominent in humans and other species. To investigate the genetic contribution
to this complex behavior, we conducted behavioral, electrophysiological, and genetic studies, using male progeny of two inbred
mouse strains (C57BL/6ByJ [B6] and 129/J [129]) and their F2 hybrids. Two loci on Chromosome (Chr) 4 were responsible for over 50% of the genetic variability in sucrose intake. These
loci apparently modulated intake by altering peripheral neural responses to sucrose. One locus affected the response threshold,
whereas the other affected the response magnitude. These findings suggest that the majority of difference in sucrose intake
between male B6 and 129 mice is due to polymorphisms of two genes that influence receptor or peripheral nervous system activity.
Received: 27 January 1997 / Accepted: 17 March 1997 相似文献