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141.
Lesa Lorenzen Huber Kalpana Shankar Kelly Caine Kay Connelly L. Jean Camp Beth Ann Walker 《International journal of human-computer interaction》2013,29(7):441-455
In-home technologies can support older adults' activities of daily living, provide physical safety and security, and connect elders to family and friends. They facilitate aging in place while reducing caregiver burden. One of older adults' primary concerns about in-home technologies is their potential to reduce human contact, particularly from cherished caregivers. In this exploratory in situ study, we provided an ecosystem of networked monitoring technologies to six older adults and their caregivers. We analyzed the amount and content of communication between them. The amount of noncomputer-mediated communication did not decrease through the 6-week study. The content of communication coalesced into four themes: communication about the technologies, communication facilitated by technologies, intrusiveness of technologies, and fun and playfulness with the technologies. Results suggest that in-home technologies, designed with sensitivity to older adults' primary motivations, have the potential to shape and tailor important relationships in later life. 相似文献
142.
基于WebGIS的城市供水管网系统的设计与实现 总被引:1,自引:0,他引:1
介绍了基于WebGIS的城市供水管网信息系统的体系结构、功能组成以及供水管网建模技术.城市供水管网系统主要包括管网建模、查询统计、爆管事故分析、运行状态监控、漏损分析、系统维护等六个方面.城市供水管网建模是进行城市供水系统规划、设计、分析与优化调度的重要支撑技术,充分发挥WebGIS的分布式与可视化地理空间信息分析的优势,结合城市供水管网的管理需求,将WebGIS技术应用到城市供水管网的建模中.该系统可为城市供水部门的高效管理提供决策依据. 相似文献
143.
James Alfred Walker Katharina Völk Stephen L. Smith Julian Francis Miller 《Genetic Programming and Evolvable Machines》2009,10(4):417-445
Parallel and distributed methods for evolutionary algorithms have concentrated on maintaining multiple populations of genotypes,
where each genotype in a population encodes a potential solution to the problem. In this paper, we investigate the parallelisation
of the genotype itself into a collection of independent chromosomes which can be evaluated in parallel. We call this multi-chromosomal evolution
(MCE). We test this approach using Cartesian Genetic Programming and apply MCE to a series of digital circuit design problems
to compare the efficacy of MCE with a conventional single chromosome approach (SCE). MCE can be readily used for many digital
circuits because they have multiple outputs. In MCE, an independent chromosome is assigned to each output. When we compare
MCE with SCE we find that MCE allows us to evolve solutions much faster. In addition, in some cases we were able to evolve
solutions with MCE that we unable to with SCE. In a case-study, we investigate how MCE can be applied to to a single objective
problem in the domain of image classification, namely, the classification of breast X-rays for cancer. To apply MCE to this
problem, we identify regions of interest (RoI) from the mammograms, divide the RoI into a collection of sub-images and use
a chromosome to classify each sub-image. This problem allows us to evaluate various evolutionary mutation operators which
can pairwise swap chromosomes either randomly or topographically or reuse chromosomes in place of other chromosomes. 相似文献
144.
PA Field 《Canadian Metallurgical Quarterly》1994,31(2):201-215
In this survey research a comparison was made between symptoms used by mothers and nurses which led them to think the baby might be "colicky." Two questionnaires, one for mothers and one for nurses, were used to collect the data. The mothers most frequently selected passes gas rectally, clenches fists, draws-up legs, cries late afternoon and evening, holds body straight, and wants to be held. The nurses selected mother states baby is inconsolable, cries more than 4 hours in 24, draws up legs and wants to feed but won't. Parents believed the colic to be related to a variety of factors; these included baby's eating behaviour, maternal anxiety, baby's and mother's diets, and baby's stress. Ten parents reported pain and screaming as symptoms of colic. 相似文献
145.
146.
Integral and membrane-associated proteins extracted from neuron-enriched perirhopalial tissue of the jellyfish Cyanea capillata were probed with a panel of lectins that recognize sugar epitopes of varying complexity. Of the 13 lectins tested, only concanavalin A, jacalin lectin and tomato lectin stained distinct bands on Western blots, indicating the presence of repeating alpha-1,6-mannoses, terminal Gal-alpha-1,6-GalNAc and repeating beta-1,4-linked GlcNAc, respectively. In whole-mounted perirhopalial tissue, jacalin lectin stained several cell types, including neurons, muscle, cilia and mucus strands. Tomato lectin stained secretory cells intensely, and neurons in a punctate fashion. Concanavalin A stained cytoplasmic epitopes in both ecto- and endodermal cells, and ectodermal secretory cells and the mucus strands emanating from them. With the exception of tomato lectin's sugar epitope, the other sugar epitopes identified in this study are "non-complex". This study suggests that while glycosylation of integral and membrane-associated proteins occurs in Cyanea, the sugars post-translationally linked to these proteins tend to be simple. 相似文献
147.
JA DeMartino ZD Konteatis SJ Siciliano G Van Riper DJ Underwood PA Fischer MS Springer 《Canadian Metallurgical Quarterly》1995,270(27):15966-15969
C5a is a 74-amino-acid glycoprotein whose receptor is a member of the rhodopsin superfamily. While antagonists have been generated to many of these receptors, similar efforts directed at family members whose natural ligands are proteins have met with little success. The recent development of hexapeptide analogs of C5a has allowed us to begin elucidation of the molecular events that lead to activation by combining a structure/activity study of the ligand with receptor mutagenesis. Removal of the hexapeptide's C-terminal arginine reduces affinity by 100-fold and eliminates the ability of the ligand to activate the receptor. Both the guanidino side chain and the free carboxyl of the arginine participate in the interaction. The guanidino group makes the energy-yielding contact with the receptor, while the free carboxylate negates "electrostatic" interference with Arg-206 of the receptor. It is the apparent movement Arg-206 induced by this set of interactions that is responsible for activation, since conversion of Arg-206 to alanine eliminates the agonist activity of the hexapeptides. Surprisingly, activation is a nearly energy-neutral event and may reflect the binding process rather than the final resting site of the ligand. 相似文献
148.
Moritz Tebbe Elizabeth Galati Gilbert C. Walker Eugenia Kumacheva 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(37)
Future progress in nanoscience and nanotechnology necessitates further development of versatile, labor‐, and cost‐efficient surface patterning strategies. A new approach to nanopatterning is reported, which utilizes surface segregation of a smooth layer of an end‐grafted homopolymer in a poor solvent. The variation in polymer grafting density yields a range of surface nanostructures, including randomly organized pinned spherical micelles, worm‐like structures, networks, and porous films. The capability to use the polymer patterns for site‐specific deposition of small molecules, polymers, or nanoparticles is shown. This versatile strategy enables patterning of curved surfaces with direct access to the substrate and no need in changing polymer composition to realize different surface patterns. 相似文献
149.
Aging and the progression of certain degenerative diseases are accompanied by increases in intracellular fluorescent material, termed "lipofuscin" and ceroid, respectively. These pigments are observed within granules composed, in part, of damaged protein and lipid. Modification of various biomolecules by aldehyde products of lipid peroxidation is believed to contribute to lipofuscin and ceroid formation. However, little direct evidence currently exists because the structures responsible for the fluorescent, cross-linked nature of this material are not well characterized. In this study, we have identified a fluorescent product formed in the reaction of Nalpha-acetyllysine and 4-hydroxy-2-nonenal (HNE), a major product of lipid peroxidation and the most reactive of these compounds under physiological conditions [Esterbauer, H., Shaur, R. J. & Zollner, H. (1991) Free Radical Biol. Med. 11, 81-128]. This fluorescent compound, characterized as a 2-hydroxy-3-imino-1,2-dihydropyrrol derivative, appears to form upon oxidative cyclization of the nonfluorescent 2:1 lysine-HNE Michael adduct-Schiff base cross-link. Polyclonal antibody was raised to the Nalpha-acetyllysine-HNE fluorophore and found to be highly specific to the chromophore structure of the compound. This antibody has been used to conclusively demonstrate that the lysine-HNE derivative of this fluorophore forms on protein upon exposure to HNE. The results of this study therefore provide the basis for future investigations on the contribution(s) of HNE-derived fluorophore formation to lipofuscin and ceroid accumulation. 相似文献
150.
PA Antinozzi L Segall M Prentki JD McGarry CB Newgard 《Canadian Metallurgical Quarterly》1998,273(26):16146-16154
The mechanism by which glucose stimulates insulin secretion from the pancreatic islets of Langerhans is incompletely understood. It has been suggested that malonyl-CoA plays a regulatory role by inhibiting fatty acid oxidation and promoting accumulation of cytosolic long-chain acyl-CoA (LC-CoA). In the current study, we have re-evaluated this "long-chain acyl-CoA hypothesis" by using molecular and pharmacologic methods to perturb lipid metabolism in INS-1 insulinoma cells or rat islets during glucose stimulation. First, we constructed a recombinant adenovirus containing the cDNA encoding malonyl-CoA decarboxylase (AdCMV-MCD), an enzyme that decarboxylates malonyl-CoA to acetyl-CoA. INS-1 cells treated with AdCMV-MCD had dramatically lowered intracellular malonyl CoA levels compared with AdCMV-betaGal-treated cells at both 3 and 20 mM glucose. Further, at 20 mM glucose, AdCMV-MCD-treated cells were less effective at suppressing [1-14C]palmitate oxidation and incorporated 43% less labeled palmitate and 50% less labeled glucose into cellular lipids than either AdCMV-betaGAL-treated or untreated INS-1 cells. Despite the large metabolic changes caused by expression of MCD, insulin secretion in response to glucose was unaltered relative to controls. The alternative, pharmacologic approach for perturbing lipid metabolism was to use triacsin C to inhibit long-chain acyl-CoA synthetase. This agent caused potent attenuation of palmitate oxidation and glucose or palmitate incorporation into cellular lipids and also caused a 47% decrease in total LC-CoA. Despite this, the drug had no effect on glucose-stimulated insulin secretion in islets or INS-1 cells. We conclude that significant disruption of the link between glucose and lipid metabolism does not impair glucose-stimulated insulin secretion in pancreatic islets or INS-1 cells. 相似文献