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排序方式: 共有319条查询结果,搜索用时 593 毫秒
91.
New procedures for measuring the pressure uniformity and pore size of press fabrics have been developed to study their role in the dewatering efficiency of a wet paper sheet and fabric system during pressing. The press nip profile of a single nip can be simulated in the laboratory using a custom built Servo-hydraulic Press Nip Simulator (SPNS) and is used to evaluate the final dryness and rewet of a handsheet with press fabric(s). Pressure uniformity can be measured with a flexible high-resolution transducer and pore size; both tests measured using water as the fluid are performed on compressed press fabric samples. A strong correlation is found between pressure uniformity parameters, mean flow pore size and final dryness for different sheets. Rewet is measured "directly" using a tracer fluid in the press fabric in our SPNS tester. Preliminary results indicate a significant reduction in rewet for some sheets with the use of an anti-rewet layer in combination withcertain press fabric designs. 相似文献
92.
Beum‐Jo Park 《Journal of forecasting》2002,21(5):381-393
Since volatility is perceived as an explicit measure of risk, financial economists have long been concerned with accurate measures and forecasts of future volatility and, undoubtedly, the Generalized Autoregressive Conditional Heteroscedasticity (GARCH) model has been widely used for doing so. It appears, however, from some empirical studies that the GARCH model tends to provide poor volatility forecasts in the presence of additive outliers. To overcome the forecasting limitation, this paper proposes a robust GARCH model (RGARCH) using least absolute deviation estimation and introduces a valuable estimation method from a practical point of view. Extensive Monte Carlo experiments substantiate our conjectures. As the magnitude of the outliers increases, the one‐step‐ahead forecasting performance of the RGARCH model has a more significant improvement in two forecast evaluation criteria over both the standard GARCH and random walk models. Strong evidence in favour of the RGARCH model over other competitive models is based on empirical application. By using a sample of two daily exchange rate series, we find that the out‐of‐sample volatility forecasts of the RGARCH model are apparently superior to those of other competitive models. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
93.
Sara Canato João D. Santos Ana S. Carvalho Kerman Aloria Margarida D. Amaral Rune Matthiesen André O. Falcao Carlos M. Farinha 《Cellular and molecular life sciences : CMLS》2018,75(24):4495-4509
Misfolded F508del-CFTR, the main molecular cause of the recessive disorder cystic fibrosis, is recognized by the endoplasmic reticulum (ER) quality control (ERQC) resulting in its retention and early degradation. The ERQC mechanisms rely mainly on molecular chaperones and on sorting motifs, whose presence and exposure determine CFTR retention or exit through the secretory pathway. Arginine-framed tripeptides (AFTs) are ER retention motifs shown to modulate CFTR retention. However, the interactions and regulatory pathways involved in this process are still largely unknown. Here, we used proteomic interaction profiling and global bioinformatic analysis to identify factors that interact differentially with F508del-CFTR and F508del-CFTR without AFTs (F508del-4RK-CFTR) as putative regulators of this specific ERQC checkpoint. Using LC–MS/MS, we identified kinesin family member C1 (KIFC1) as a stronger interactor with F508del-CFTR versus F508del-4RK-CFTR. We further validated this interaction showing that decreasing KIFC1 levels or activity stabilizes the immature form of F508del-CFTR by reducing its degradation. We conclude that the current approach is able to identify novel putative therapeutic targets that can be ultimately used to the benefit of CF patients. 相似文献
94.
Anske Van den Abbeele Sarah De Clercq Ariane De Ganck Veerle De Corte Berlinda Van Loo Sameh Hamdy Soror Vasundara Srinivasan Jan Steyaert Joël Vandekerckhove Jan Gettemans 《Cellular and molecular life sciences : CMLS》2010,67(9):1519-1535
RNA interference has tremendously advanced our understanding of gene function but recent reports have exposed undesirable
side-effects. Recombinant Camelid single-domain antibodies (VHHs) provide an attractive means for studying protein function without affecting gene expression.
We raised VHHs against gelsolin (GsnVHHs), a multifunctional actin-binding protein that controls cellular actin organization
and migration. GsnVHH-induced delocalization of gelsolin to mitochondria or the nucleus in mammalian cells reveals distinct
subpopulations including free gelsolin and actin-bound gelsolin complexes. GsnVHH 13 specifically recognizes Ca2+-activated gelsolin (K
d ~10 nM) while GsnVHH 11 binds gelsolin irrespective of Ca2+ (K
d ~5 nM) but completely blocks its interaction with G-actin. Both GsnVHHs trace gelsolin in membrane ruffles of EGF-stimulated
MCF-7 cells and delay cell migration without affecting F-actin severing/capping or actin nucleation activities by gelsolin.
We conclude that VHHs represent a potent way of blocking structural proteins and that actin nucleation by gelsolin is more
complex than previously anticipated. 相似文献
95.
Speliotes EK Willer CJ Berndt SI Monda KL Thorleifsson G Jackson AU Lango Allen H Lindgren CM Luan J Mägi R Randall JC Vedantam S Winkler TW Qi L Workalemahu T Heid IM Steinthorsdottir V Stringham HM Weedon MN Wheeler E Wood AR Ferreira T Weyant RJ Segrè AV Estrada K Liang L Nemesh J Park JH Gustafsson S Kilpeläinen TO Yang J Bouatia-Naji N Esko T Feitosa MF Kutalik Z Mangino M Raychaudhuri S Scherag A Smith AV Welch R Zhao JH Aben KK Absher DM Amin N Dixon AL Fisher E Glazer NL Goddard ME 《Nature genetics》2010,42(11):937-948
Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ~ 2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10??), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation. 相似文献
96.
97.
Robert A. Nye 《Annals of science》2013,70(3):266-268
98.
Gerardo?Carranza Raquel?Casta?o Mónica?L.?Fanarraga Juan?Carlos?Villegas Jo?o?Gon?alves Jesus?Avila Marco?Marenchino Ramón?Campos-Olivas Guillermo?Montoya Juan?Carlos?ZabalaEmail author 《Cellular and molecular life sciences : CMLS》2013,70(2):357-371
Tubulin cofactors (TBCs) participate in the folding, dimerization, and dissociation pathways of the tubulin dimer. Among them, TBCB and TBCE are two CAP-Gly domain-containing proteins that together efficiently interact with and dissociate the tubulin dimer. In the study reported here we showed that TBCB localizes at spindle and midzone microtubules during mitosis. Furthermore, the motif DEI/M-COO? present in TBCB, which is similar to the EEY/F-COO? element characteristic of EB proteins, CLIP-170, and α-tubulin, is required for TBCE–TBCB heterodimer formation and thus for tubulin dimer dissociation. This motif is responsible for TBCB autoinhibition, and our analysis suggests that TBCB is a monomer in solution. Mutants of TBCB lacking this motif are derepressed and induce microtubule depolymerization through an interaction with EB1 associated with microtubule tips. TBCB is also able to bind to the chaperonin complex CCT containing α-tubulin, suggesting that it could escort tubulin to facilitate its folding and dimerization, recycling or degradation. 相似文献
99.
Identification of the gene responsible for methylmalonic aciduria and homocystinuria, cblC type 总被引:10,自引:0,他引:10
Lerner-Ellis JP Tirone JC Pawelek PD Doré C Atkinson JL Watkins D Morel CF Fujiwara TM Moras E Hosack AR Dunbar GV Antonicka H Forgetta V Dobson CM Leclerc D Gravel RA Shoubridge EA Coulton JW Lepage P Rommens JM Morgan K Rosenblatt DS 《Nature genetics》2006,38(1):93-100
Methylmalonic aciduria and homocystinuria, cblC type (OMIM 277400), is the most common inborn error of vitamin B(12) (cobalamin) metabolism, with about 250 known cases. Affected individuals have developmental, hematological, neurological, metabolic, ophthalmologic and dermatologic clinical findings. Although considered a disease of infancy or childhood, some individuals develop symptoms in adulthood. The cblC locus was mapped to chromosome region 1p by linkage analysis. We refined the chromosomal interval using homozygosity mapping and haplotype analyses and identified the MMACHC gene. In 204 individuals, 42 different mutations were identified, many consistent with a loss of function of the protein product. One mutation, 271dupA, accounted for 40% of all disease alleles. Transduction of wild-type MMACHC into immortalized cblC fibroblast cell lines corrected the cellular phenotype. Molecular modeling predicts that the C-terminal region of the gene product folds similarly to TonB, a bacterial protein involved in energy transduction for cobalamin uptake. 相似文献
100.
Zanke BW Greenwood CM Rangrej J Kustra R Tenesa A Farrington SM Prendergast J Olschwang S Chiang T Crowdy E Ferretti V Laflamme P Sundararajan S Roumy S Olivier JF Robidoux F Sladek R Montpetit A Campbell P Bezieau S O'Shea AM Zogopoulos G Cotterchio M Newcomb P McLaughlin J Younghusband B Green R Green J Porteous ME Campbell H Blanche H Sahbatou M Tubacher E Bonaiti-Pellié C Buecher B Riboli E Kury S Chanock SJ Potter J Thomas G Gallinger S Hudson TJ Dunlop MG 《Nature genetics》2007,39(8):989-994
Using a multistage genetic association approach comprising 7,480 affected individuals and 7,779 controls, we identified markers in chromosomal region 8q24 associated with colorectal cancer. In stage 1, we genotyped 99,632 SNPs in 1,257 affected individuals and 1,336 controls from Ontario. In stages 2-4, we performed serial replication studies using 4,024 affected individuals and 4,042 controls from Seattle, Newfoundland and Scotland. We identified one locus on chromosome 8q24 and another on 9p24 having combined odds ratios (OR) for stages 1-4 of 1.18 (trend; P = 1.41 x 10(-8)) and 1.14 (trend; P = 1.32 x 10(-5)), respectively. Additional analyses in 2,199 affected individuals and 2,401 controls from France and Europe supported the association at the 8q24 locus (OR = 1.16, trend; 95% confidence interval (c.i.): 1.07-1.26; P = 5.05 x 10(-4)). A summary across all seven studies at the 8q24 locus was highly significant (OR = 1.17, c.i.: 1.12-1.23; P = 3.16 x 10(-11)). This locus has also been implicated in prostate cancer. 相似文献