items found (Total items:2350)
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Author: Backberg, M.; Meister, B.
Description: Tubby and tubby-like proteins (TULPs) are encoded by members of a small gene family. An autosomal recessive mutation in the mouse tub gene leads to blindness, deafness, and maturity-onset obesity. The mechanisms by which the mutation causes the obesity syndrome has not been established. We compared obese tub/tub mice and their lean littermates in order to find abnormalities within the mediobasal hypothalamus, a region intimately associated with the regulation of body weight. Using an antiserum to the vesicular acetylcholine transporter (VAChT), a marker for cholinergic neurons, many unusually large VAChT-immunoreactive (-ir) nerve terminals, identified by colocalization with the synaptic vesicle protein synaptophysin, were demonstrated in the hypothalamic arcuate nucleus of obese tub/tub mice. Double-labeling showed that VAChT-ir nerve endings also contained glutamic acid decarboxylase (GAD), a marker for gamma-aminobutyric acid (GABA) neurons. The VAChT- and GAD-ir nerve terminals were in close contact with blood vessels, identified with antisera to platelet endothelial cell adhesion molecule-1 (PECAM; also called CD31), laminin, smooth muscle actin (SMA), and glucose transporter-1 (GLUT1). Such large cholinergic and GABAergic nerve terminals surrounding blood vessels were not seen in the arcuate nucleus of lean tub/+ mice. The presence of abnormal cholinergic/GABAergic vascular innervation in the arcuate nucleus suggests that alterations in this region, which contains neurons that receive information from the periphery and which relays information about the energy status to other parts of the brain, may be central in the development of the obese phenotype in animals with an autosomal recessive mutation in the tub gene.
Title: Abnormal cholinergic and GABAergic vascular innervation in the hypothalamic arcuate nucleus of obese tub/tub mice
Subject headings: Acetylcholine/*metabolism; Adaptor Proteins, Signal Transducing; Animals; Arcuate Nucleus of Hypothalamus/blood supply/*metabolism; Blood Vessels/innervation; Carrier Proteins/metabolism; Glutamate Decarboxylase/metabolism; Immunohistochemistry; *Membrane Transport Proteins; Mice; Mutation; Obesity/*physiopathology; Polymerase Chain Reaction; Presynaptic Terminals/metabolism; Proteins/*genetics; Synaptophysin/metabolism; Vesicular Acetylcholine Transport Proteins; *Vesicular Transport Proteins; gamma-Aminobutyric Acid/*metabolism
Publication: Synapse (New York, N.Y.)
Full text: http://onlinelibrary.wiley.com/doi/10.1002/syn.20024/abstract
Cited by: https://scholar.google.com/scholar?cites=17401664663600608224&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Baddeley, A.D.; Thomson, N.; Buchanan, M.
Description: A number of experiments explored the hypothesis that immediate memory span is not constant, but varies with the length of the words to be recalled. Results showed: (1) Memory span is inversely related to word length across a wide range of materials; (2) When number of syllables and number of phonemes are held constant, words of short temporal duration are better recalled than words of long duration; (3) Span could be predicted on the basis of the number of words which the subject can read in approximately 2 sec; (4) When articulation is suppressed by requiring the subject to articulate an irrelevant sound, the word length effect disappears with visual presentation, but remains when presentation is auditory. The results are interpreted in terms of a phonemically-based store of limited temporal capacity, which may function as an output buffer for speech production, and as a supplement to a more central working memory system.
Title: Word length and the structure of short-term memory
Subject headings: Immediate memory span; Word length
Publication: Journal of Verbal Learning and Verbal Behavior
Full text: http://labs.la.utexas.edu/gilden/files/2016/03/1-s2.0-S0022537175800454-main.pdf
Cited by: https://scholar.google.com/scholar?cites=14177450593503146395&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Baden, D.A.; McLean, T.L.; Tucker, R.; Noakes, T.D.; St Clair Gibson, A.
Description: OBJECTIVES: To determine the effect of unknown exercise duration and an unexpected increase in exercise duration on rating of perceived exertion (RPE), affect, and running economy during treadmill running. METHODS: Sixteen well trained male and female runners completed three bouts of treadmill running at 75% of their peak treadmill running speed. In the first trial, they were told to run for 20 minutes and were stopped at 20 minutes (20 MIN). In another trial, they were told to run for 10 minutes, but at 10 minutes were told to run for a further 10 minutes (10 MIN). In the final trial, they were not told for how long they would be running but were stopped after 20 minutes (unknown, UN). During each of the running bouts, RPE, oxygen consumption (ml/kg/min), heart rate (beats/min), stride frequency (min(-1)), affect scores (arbitrary units), and attentional focus (percentage associative thought scores) were recorded. RESULTS: RPE increased significantly between 10 and 11 minutes in the 10 MIN compared with the 20 MIN and UN trials (p<0.05). The affect score decreased significantly between 10 and 11 minutes in the 10 MIN compared with the 20 MIN trial (p<0.05). Running economy, as measured by oxygen consumption, was significantly lower in the UN compared with the 20 MIN trial from 10 to 19 minutes (p<0.05). CONCLUSIONS: The change in RPE between 10 and 11 minutes in the 10 MIN trial suggests that RPE is not purely a measure of physical exertion, as treadmill speed was maintained at a constant pace both before and after the unexpected increase in exercise duration. The associated changes in affect score at similar times in the 10 MIN trial supports the hypothesis that RPE has an affective component.
Title: Effect of anticipation during unknown or unexpected exercise duration on rating of perceived exertion, affect, and physiological function
Subject headings: Affect--physiology; Exercise--physiology, psychology; Exercise Test--methods; Female; Heart Rate--physiology; Humans; Male; Oxygen Consumption--physiology; Physical Endurance--physiology; Physical Exertion--physiology; Running--physiology, psychology
Publication: British Journal of Sports Medicine
Pages: 742-6; discussion 742-6
Full text: http://www.ncbi.nlm.nih.gov/pubmed/16183771
Cited by: https://scholar.google.com/scholar?cites=14797282875639022006&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Badran, O.; Mamlook, R.; Abdulhadi, E.
Description: The rapid expansion of the use of solar energy power plants worldwide is a subject that is being followed with interest. Fuzzy logic methodology is used for evaluating the solar thermal power technology, it compresses huge amount of data into smaller sets, and it has the ability to decide between different solar technologies on the basis of their benefits and costs. The most often considered solar technologies were parabolic trough, central receiver, dish sterling engine, compact linear Fresnel reflector (CLFR), solar chimney, photovoltaic (PV), and solar pond. The aim of our research is to provide the needed information to make a judgment or a decision of adopting the most preferred solar technology in terms of installation and development using fuzzy set methodology. The criteria of the evaluation were based on different parameters, i.e., power capacity, efficiency, availability, capacity factor, storage capability, cost, maturity, water usage, land usage, and safety. The key barriers and features for each technology on the basis of benefit-to-cost ratios are addressed. The results showed that CLFR was found to be the best choice in terms of research, development, and implementation, followed by parabolic trough technology, then the central receiver technology, dish sterling engine, solar chimney, PV, and solar pond, according to the order of preference.
Title: Toward clean environment: evaluation of solar electric power technologies using fuzzy logic
Subject headings: Fuzzy Sets Methodology; Solar Electric Power; Control Technology
Publication: Clean Technologies and Environmental Policy
Full text: http://link.springer.com/10.1007/s10098-011-0407-8
Cited by: https://scholar.google.com/scholar?cites=9151401587028699759&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Baer, S.G.; Blair, J.M.; Collins, S.L.; Knapp, A.K.
Description: In native tallgrass prairie, soil depth and nitrogen (N) availability strongly influence aboveground net primary productivity (ANPP) and plant species composition. We manipulated these factors in a newly restored grassland to determine if these resources similarly constrain productivity and diversity during the initial three years of grassland establishment. Four types of experimental plots with six treatment combinations of deep and shallow soil at reduced-, ambient-, and enriched-N availability formed the basis of this study. The soil responses to the experimental treatments were examined over three years, and patterns in diversity and productivity were examined in year 3. The soil depth treatment did not significantly affect soil carbon (C) and N pools or ANPP and diversity. A pulse amendment of C added to the soil prior to planting increased soil microbial biomass and decreased potential net N mineralization rates to effectively reduce N availability throughout the study. Nitrogen availability declined over time in nonamended soils as a result of plant establishment, but adding fertilizer N alleviated the increasing immobilization potential of the soil. The level of ANPP was lowest and diversity highest in the reduced-N treatment, whereas the enriched-N treatment resulted in high productivity, but low diversity. As a result, diversity was inversely correlated with productivity in these newly established communities. The same mechanism invoked to explain decreased diversity under nutrient enrichment in old-field ecosystems and native grasslands (e.g., reduced light availability with increased production) was supported in the restored prairie by the positive relationship between ANPP and intercepted light, and a strong correlation between light availability and diversity. The effects of nutrient availability on plant community composition (diversity and richness) were due primarily to the responses of prairie species, as the productivity of early successional, nonprairie species was less than 1% of total ANPP after three years of establishment. These results show that the effects of resource availability on productivity and diversity are similar in young and mature grasslands, and that manipulation of a limiting nutrient during grassland establishment can influence floristic composition, with consequences for long-term patterns of diversity in restored ecosystems.
Title: Soil Resources Regulate Productivity And Diversity In Newly Established Tallgrass Prairie
Subject headings: Aboveground net primary productivity (ANPP); Diversity; Grassland; Konza Prairie, Kansas (USA); Nutrient enrichment; Productivity; Restoration; Richness; Tallgrass prairie
Full text: http://baerlabs.siu.edu/Baer%20et%20al%202003%20Ecology.pdf
Cited by: https://scholar.google.com/scholar?cites=344641351839989726&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Bailey, A.; Le Couteur, A.; Gottesman, I.; Bolton, P.; Simonoff, E.; Yuzda, E.; Rutter, M.
Description: Two previous epidemiological studies of autistic twins suggested that autism was predominantly genetically determined, although the findings with regard to a broader phenotype of cognitive, and possibly social, abnormalities were contradictory. Obstetric and perinatal hazards were also invoked as environmentally determined aetiological factors. The first British twin sample has been re-examined and a second total population sample of autistic twins recruited. In the combined sample 60% of monozygotic (MZ) pairs were concordant for autism versus no dizygotic (DZ) pairs; 92% of MZ pairs were concordant for a broader spectrum of related cognitive or social abnormalities versus 10% of DZ pairs. The findings indicate that autism is under a high degree of genetic control and suggest the involvement of multiple genetic loci. Obstetric hazards usually appear to be consequences of genetically influenced abnormal development, rather than independent aetiological factors. Few new cases had possible medical aetiologies, refuting claims that recognized disorders are common aetiological influences.
Title: Autism as a strongly genetic disorder: evidence from a British twin study
Subject headings: Abnormalities, Multiple/diagnosis/genetics/psychology; Adolescent; Adult; Autistic Disorder/diagnosis/*genetics/psychology; Child; Child, Preschool; Diseases in Twins/*genetics/psychology; Female; Follow-Up Studies; Great Britain; Humans; Infant; Infant, Newborn; Intelligence/genetics; Male; Models, Genetic; Personality Assessment; Pregnancy; Prenatal Exposure Delayed Effects; Risk Factors; Social Adjustment; Social Environment; Twins, Dizygotic/genetics/psychology; Twins, Monozygotic/genetics/psychology
Publication: Psychological Medicine
Full text: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=5025556&fileId=S0033291700028099
Cited by: https://scholar.google.com/scholar?cites=8534804613750023342&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Bailey, W.C.
Description: If deterrence is a communication effect as Gibbs and others contend, then Chicago provides an ideal research setting, since there is close geographic proximity between the place where first degree murders are committed and the place where the convicted murderers are executed. Accordingly, Chicago residents, including would-be killers, should have had a more direct awareness of murder and its possible consequence (the certainty of execution) than residents of larger jurisdictions such as States or the Nation. The model used represents the hypothesis that the monthly number of first degree murders is a function of the number of executions for first degree murder, the certainty of arrest for first degree murder, the certainty of imprisonment for first degree murder, population density, the percent of the city's budget expended on public assistance for the homeless and other needy adults and children and the season of the year. To examine the effect of executions on first degree murders, a series of multiple regresson analyses were performed where various execution measures and time lag structures were considered. In addition, more general monthly homicide figures similar to those included in the FBI's category of murder and nonnegligent manslaughter were considered in the analysis for comparative purposes and to determine the impact of executions on total criminal homicides in Chicago. In line with the brutalization argument, this analysis suggests that the net effect of executions may well have been to increase rather than decrease Chicago first degree murders and total criminal homicides. This finding is consistent with a number of early and more recent investigations of the brutalization effect of capital punishment in the United States and is only partially at odds with one study. Further, the findings are consistent with the fact that not a single reputable study has yet shown that capital punishment is an effective deterrent to murder.
Title: Disaggregation in Deterrence and Death Penalty Research: The Case of Murder in Chicago
Subject headings: Capital punishment ; Deterrence effectiveness ; Illinois
Publication: The Journal of Criminal Law and Criminology (1973-)
Full text: http://scholarlycommons.law.northwestern.edu/cgi/viewcontent.cgi?article=6381&context=jclc
Cited by: https://scholar.google.com/scholar?cites=16757390386091933788&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Bajji, M.; Kinet, J.-M.; Lutts, S.
Description: Salt stress effects on growth, osmotic adjustment, mineral and organic contents and soluble peroxidase activities were determined in roots and leaves of Atriplex halimus and their corresponding callus cultures. Low NaCl doses (150 mM) promoted shoot growth, corroborating the halophilic nature of this species; in these stress conditions, Na+ concentration markedly increased in the leaves indicating that salinity resistance was not associated with the ability of the plants to restrict sodium accumulation in the aerial part. Whole organs and their corresponding calli were able to cope with high NaCl doses but there was no clear correspondence between the physiological behaviour of cell culture and whole plant. For several physiological parameters (osmotic potential (Ψs), mineral content, proline accumulation), roots were less affected by NaCl than leaves while both root and leaf calli behaved in the same way in response to salinity. NaCl-induced modifications of the recorded parameters are discussed in relation to the mechanisms of salinity resistance in this species. Evidence indicated the existence of a cellular basis for salinity resistance in A. halimus, but the expression of this cellular property at organ level appeared to be masked by the physiological complexity of the intact plant and the nature of the whole organ response was apparently determined primarily by regulation mechanisms assigned by the differentiated tissue organization.
Title: Salt stress effects on roots and leaves of Atriplex halimus L. and their corresponding callus cultures
Subject headings: Atriplex halimus L.; Ion accumulation; Osmotic adjustment; Organic solutes; Salinity; Tissue culture
Publication: Plant Science
Full text: http://linkinghub.elsevier.com/retrieve/pii/S0168945298001162
Cited by: https://scholar.google.com/scholar?cites=553414068913570136&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article
Author: Bak, T.; Nowotny, J.; Rekas, M.; Sorrell, C.C.
Description: The present work considers hydrogen generation from water using solar energy. The work is focused on the materials-related issues in the development of high-efficiency photo-electrochemical cells (PECs). The property requirements for photo-electrodes, in terms of semiconducting and electrochemical properties and their impact on the performance of PECs, are outlined. Different types of PECs are overviewed and the impact of the PEC structure and materials selection on the conversion efficiency of solar energy are considered.
Trends in research in the development of high-efficiency PECs are discussed. It is argued that very sophisticated materials engineering must be used for processing the materials that will satisfy the specific requirements for photo-electrodes. An important issue in the processing of these materials is the bulk vs. interface properties at the solid/solid interfaces (e.g., grain boundaries) and solid/liquid interfaces (e.g., electrode/electrolyte interface). Consequently, the development of PECs with the efficiency required for commercialization requires the application of up-to-date materials processing technology.
The performance of PECs is considered in terms of:
excitation of electron–hole pair in photo-electrodes;
charge separation in photo-electrodes;
electrode processes and related charge transfer within PECs;
generation of the PEC voltage required for water decomposition.
This work also gives empirical data on the performance of PECs of different structures and materials selection.
It is argued that PEC technology is the most promising technology for hydrogen production owing to several reasons:
PEC technology is based on solar energy, which is a perpetual source of energy, and water, which is a renewable resource;
PEC technology is environmentally safe, with no undesirable byproducts;
PEC technology may be used on both large and small scales;
PEC technology is relatively uncomplicated.
According to current predictions, the production of hydrogen will skyrocket by 2010 (Morgan and Sissine, Congressional Research Service, Report for Congress. The Committee for the National Institute for the Environment, Washington, DC, 20006-1401, 28 April 1995). Consequently, seed funding already has been allocated to several national research programs aiming at the development of hydrogen technology. The countries having access to this PEC technology are likely to form the OPEC of the future.
Title: Photo-electrochemical hydrogen generation from water using solar energy. Materials-related aspects
Subject headings: Hydrogen generation; Photo-electrodes; Solar energy conversion; Photo-electrochemistry; Photo-cells; Semiconducting materials
Publication: International Journal of Hydrogen Energy
Full text: http://www.academia.edu/download/36652006/Int._J._Hydrogen_Energy_1.pdf
Cited by: https://scholar.google.com/scholar?cites=183291234036553627&as_sdt=1000005&sciodt=0,16&hl=en
Format: Journal Article