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41.
Dr. Marina Tanasova Matthew Plutschack Megan E. Muroski Prof. Shana J. Sturla Prof. Geoffrey F. Strouse Prof. D. Tyler McQuade 《Chembiochem : a European journal of chemical biology》2013,14(10):1263-1270
Recent publications suggest that high dietary fructose might play a significant role in cancer metabolism and can exacerbate a number of aspects of metabolic syndrome. Addressing the role that fructose plays in human health is a controversial question and requires a detailed understanding of many factors including the mechanism of fructose transport into healthy and diseased cells. Fructose transport into cells is thought to be largely mediated by the passive hexose transporters Glut2 and Glut5. To date, no probes that can be selectively transported by one of these enzymes but not by the other have been identified. The data presented here indicate that, in MCF‐7 cells, a 1‐amino‐2,5‐anhydro‐D ‐mannitol‐based fluorescent NBDM probe is transported twice as efficiently as fructose and that this takes place with the aid of Glut5. Its Glut5 specificity and differential uptake in cancer cells and in normal cells suggest this NBDM probe as a potentially useful tool for cross‐cell‐line correlation of Glut5 transport activity. 相似文献
42.
Heat exchanger networks are an integral part of chemical processes as they recover available heat and reduce utility consumption, thereby improving the overall economics of an industrial plant. This paper focuses on heat exchanger network design for multi-period operation wherein the operating conditions of a process may vary with time. A typical example is the hydrotreating process in petroleum refineries where the operators increase reactor temperature to compensate for catalyst deactivation. Superstructure based multi-period models for heat exchanger network design have been proposed previously employing deterministic optimisation algorithms, e.g. (0005 and 0180). Stochastic optimisation algorithms have also been applied for the design of flexible heat exchanger networks recently (0110 and 0115). The present work develops an optimisation approach using simulated annealing for design of heat exchanger networks for multi-period operation. A comparison of the new optimisation approach with previous deterministic optimisation based design approaches is presented to illustrate the utilisation of simulated annealing in design of optimal heat exchanger network configurations for multi-period operation. 相似文献
43.
This paper describes a case study of a neighborhood pub in British Columbia, Canada. This case study is an examination of three common pub occupations-bartending, waitressing and cooking (n = 17). The aims of this study are to determine the biomechanical loads of job tasks identified as physically demanding for the three occupations analyzed, to assess the potential risk of musculoskeletal injury in these job tasks, and to recommend injury prevention measures. Risk of musculoskeletal injury was assessed with four validated methods (RULA, NIOSH lifting equation, Shoaf pulling model, 3D Static Strength prediction program). Tasks commonly and frequently performed were observed to pose some risk to the working populations and require investigation and changes soon as indicated by the upper extremity and low-back assessment procedures used. Mean combined compression at the lumbrosacral disc in common tasks have been demonstrated to exceed the action limit described by NIOSH. Ligament strain was observed to reach as high as 18% at the lumbosacral joint. 相似文献
44.
Piper Megan E.; Piasecki Thomas M.; Federman E. Belle; Bolt Daniel M.; Smith Stevens S.; Fiore Michael C.; Baker Timothy B. 《Canadian Metallurgical Quarterly》2004,72(2):139
The dependence construct fills an important explanatory role in motivational accounts of smoking and relapse. Frequently used measures of dependence are either atheoretical or grounded in a unidimensional model of physical dependence. This research creates a multidimensional measure of dependence that is based on theoretically grounded motives for drug use and is intended to reflect mechanisms underlying dependence. Data collected from a large sample of smokers (N = 775) indicated that all 13 subscales of the Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) have acceptable internal consistency, are differentially present across levels of smoking heaviness, and have a multidimensional structure. Validity analyses indicated the WISDM-68 subscales are significantly related to dependence criteria such as smoking heaviness and to 4th edition Diagnostic and Statistical Manual of Mental Disorders symptoms of dependence and relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Zaslow Martha J.; Weinfield Nancy S.; Gallagher Megan; Hair Elizabeth C.; Ogawa John R.; Egeland Byron; Tabors Patton O.; De Temple Jeanne M. 《Canadian Metallurgical Quarterly》2006,42(1):27
This study examined predictions from preschool parenting measures to middle childhood cognitive and socioemotional child outcomes to explore whether parenting assessment methodologies that require more time, training, and expense yield better predictions of child outcomes than less intensive methodologies. Mother-child dyads (N=278) in low-income African American families were assessed when the child was in preschool, using maternal report, the Home Observation for Measurement of the Environment-Short Form (P. Baker & F. Mott, 1989; R. Bradley & B. Caldwell, 1984), and structured observational measures of parenting. Child outcomes reported by children, mothers, teachers, and direct assessment were collected 4 years later. All parenting methodologies showed some predictive value; however, observational parenting measures showed the strongest and most consistent predictions of child outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
47.
McKay James R.; Alterman Arthur I.; Cacciola John S.; Rutherford Megan J.; O'Brien Charles P.; Koppenhaver Janelle 《Canadian Metallurgical Quarterly》1997,65(5):778
Ninety-eight male cocaine-dependent patients who completed an intensive outpatient program (IOP) were randomly assigned to either standard group counseling (STND) or individualized relapse prevention (RP) aftercare. Heavier cocaine and alcohol use during IOP and low self-efficacy predicted more cocaine use during the treatment phase of the study, whereas lifetime diagnoses of alcohol dependence, major depression, and any anxiety disorder predicted less cocaine use. Rates of complete abstinence during the 6-month study period were higher in STND than RP, whereas RP was more effective in limiting the extent of cocaine use in those who used during Months 1-3. Matching analyses indicated patients who failed to achieve remission from cocaine dependence during IOP and those with a commitment to absolute abstinence did better in RP than in STND, whereas patients with other abstinence goals did better in STND than RP. Several differences in experiences before cocaine use and "near-miss" episodes were also identified. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Adrian Field Karen Witten Elizabeth Robinson Megan Pledger 《Urban Policy and Research》2004,22(2):189-205
This article explores patterns of access to services, amenities and facilities in two neighbouring New Zealand cities. An area-level indicator of community resource access, based on priorities identified by caregivers of young children, is analysed alongside census data to examine associations with community resource access in each city. Analysis reveals variations in resource access between the two cities that could not be solely explained by population density. Associations were found between resource access and patterns of deprivation, population density, age, and families with children. Of particular note was a positive association between areas of higher levels of resource access and areas of higher levels of deprivation within cities. There were, however, higher overall levels of resource access in the city with a less deprived profile. These findings support action by both central and local government to ensure equitable resource distribution to promote local well-being. 相似文献
49.
Back Cover: Hydrophobic Triaryl‐Substituted β‐Lactams as Activity‐Based Probes for Profiling Eukaryotic Enzymes and Host–Pathogen Interactions (ChemBioChem 15/2014) 下载免费PDF全文
50.
Biofilm‐Eradicating Properties of Quaternary Ammonium Amphiphiles: Simple Mimics of Antimicrobial Peptides 下载免费PDF全文
Megan C. Jennings Laura E. Ator Thomas J. Paniak Prof. Dr. Kevin P. C. Minbiole Prof. Dr. William M. Wuest 《Chembiochem : a European journal of chemical biology》2014,15(15):2211-2215
Bacterial biofilms are difficult to eradicate because of reduced antibiotic sensitivity and altered metabolic processes; thus, the development of new approaches to biofilm eradication is urgently needed. Antimicrobial peptides (AMPs) and quaternary ammonium cations (QACs) are distinct, yet well‐known, classes of antibacterial compounds. By mapping the general regions of charge and hydrophobicity of QACs onto AMP structures, we designed a small library of QACs to serve as simple AMP mimics. In order to explore the role that cationic charge plays in biofilm eradication, structures were varied with respect to cationic character, distribution of charge, and alkyl side chain. The reported compounds possess minimum biofilm eradication concentrations (MBEC) as low as 25 μM against Gram‐positive biofilms, making them the most active anti‐biofilm structures reported to date. These potent AMP mimics were synthesized in 1–2 steps and hint at the minimal structural requirements for biofilm destruction. 相似文献