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Literature Showing (literature + showing)

Distribution by Scientific Domains
Medical Sciences28%
Humanities and Social Sciences28%
Business, Economics, Finance and Accounting28%

Selected Abstracts

The effects of selective breeding for differential rates of 50-kHz ultrasonic vocalizations on emotional behavior in rats

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2009
Jeffrey Burgdorf
Abstract Fifty-kHz ultrasonic vocalizations have previously been shown to be positively correlated with reward and appetitive social behavior in rats, and to reflect a positive affective state. In this study, rats selectively bred for high and low rates of 50-kHz vocalizations as juveniles were tested as adults in a battery of behavioral tests for social/emotional behaviors. We found that animals selectively bred for high rates of 50-kHz vocalizations exhibited more crosses into the center area of the open field apparatus, were more likely to show a preference for a dilute sucrose solution (.8%) compared to tap water, and were less aggressive than randomly bred animals. Conversely, animals bred for low rates of 50-kHz calls produced more fecal boli during both open field testing and "tickling" stimulation, and made less contact with conspecifics in a social interaction test compared to randomly bred animals. We also observed that low line rats have elevated brain levels of cholecystokinin (CCK) in the cortex, which is consistent with literature showing that CCK content in the cortex is positively correlated with rates of aversive 22-kHz USVs. Conversely, high line animals had elevated levels of met-enkephalin in several brain regions, which is consistent with the role of endogenous-opioids in the generation 50-kHz USVs and positive affect. These results suggest that animals bred for high rates of 50-kHz may show a stress resilient phenotype, whereas low line rats may show a stress prone phenotype. As such these animals could provide novel insights into the neurobiology of emotion. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 51: 34,46, 2009 [source]

ECONOMIC EFFECTS OF SMOKING BANS ON RESTAURANTS AND PUBS

ECONOMIC AFFAIRS, Issue 4 2008
Barrie Craven
The United Kingdom has recently enacted smoking bans in public places such as restaurants and pubs. Public health advocates argue that bans are necessary because non-smokers need protection from second-hand smoke. Advocates also claim that bans do not exert harm on owners because of a vast empirical literature showing that restaurants and bars in the United States never suffer harm following bans. This paper examines whether these claims are true by developing a model within the Coasian framework whereby owners of businesses have incentives to deal with smoking disputes between smokers and non-smokers. Our model demonstrates that it is incorrect to argue that smoking bans are necessary because the private market has no method of attempting to solve smoking problems. It also predicts that bans exert different effects on different businesses: some will be unaffected while others will experience losses or gains. Our literature review reveals that predictions of differential effects are consistent with the empirical evidence. [source]

Ethnic Differences in Birth Outcomes in England,

FISCAL STUDIES, Issue 1 2006
Lorraine Dearden
Abstract This paper uses the Millennium Cohort Study to look at ethnic differences in birth outcomes for a cohort of English children born in 2000 and 2001. There is an increasingly large literature showing that longer gestation and higher birthweight are positively associated with cognitive and non-cognitive outcomes later in life, so understanding sources of ethnic differences in these outcomes and identifying factors that may influence birth outcomes has a lot of potential policy interest. This paper shows that even after controlling for background characteristics in a number of ways, there still remain unexplained differences in both gestation and birthweight outcomes across broad ethnic groups. It also suggests, however, that there may be potential policy levers that could be used to narrow this ethnic gap in birth outcomes, such as reducing the proportion of underweight Asian mothers and overweight Black mothers and increasing ethnic minority attendance at antenatal classes. [source]

Characterization of White Matter Microstructure in Fetal Alcohol Spectrum Disorders

ALCOHOLISM, Issue 3 2009
Susanna L. Fryer
Background:, Exposure to alcohol during gestation is associated with CNS alterations, cognitive deficits, and behavior problems. This study investigated microstructural aspects of putative white matter abnormalities following prenatal alcohol exposure. Methods:, Diffusion tensor imaging was used to assess white matter microstructure in 27 youth (age range: 8 to 18 years) with (n = 15) and without (n = 12) histories of heavy prenatal alcohol exposure. Voxelwise analyses, corrected for multiple comparisons, compared fractional anisotropy (FA) and mean diffusivity (MD) between groups, throughout the cerebrum. Results:, Prenatal alcohol exposure was associated with low FA in multiple cerebral areas, including the body of the corpus callosum and white matter innervating bilateral medial frontal and occipital lobes. Fewer between-group differences in MD were observed. Conclusions:, These data provide an account of cerebral white matter microstructural integrity in fetal alcohol spectrum disorders and support extant literature showing that white matter is a target of alcohol teratogenesis. The white matter anomalies characterized in this study may relate to the neurobehavioral sequelae associated with gestational alcohol exposure, especially in areas of executive dysfunction and visual processing deficits. [source]

High specificity generally characterizes mycorrhizal association in rare lady's slipper orchids, genus Cypripedium

MOLECULAR ECOLOGY, Issue 2 2005
RICHARD P. SHEFFERSON
Abstract Lady's slipper orchids (Cypripedium spp.) are rare terrestrial plants that grow throughout the temperate Northern Hemisphere. Like all orchids, they require mycorrhizal fungi for germination and seedling nutrition. The nutritional relationships of adult Cypripedium mycorrhizae are unclear; however, Cypripedium distribution may be limited by mycorrhizal specificity, whether this specificity occurs only during the seedling stage or carries on into adulthood. We attempted to identify the primary mycorrhizal symbionts for 100 Cypripedium plants, and successfully did so with two Cypripedium calceolus, 10 Cypripedium californicum, six Cypripedium candidum, 16 Cypripedium fasciculatum, two Cypripedium guttatum, 12 Cypripedium montanum, and 11 Cypripedium parviflorum plants from a total of 44 populations in Europe and North America, yielding fungal nuclear large subunit and mitochondrial large subunit sequence and RFLP (restriction fragment length polymorphism) data for 59 plants. Because orchid mycorrhizal fungi are typically observed without fruiting structures, we assessed fungal identity through direct PCR (polymerase chain reaction) amplification of fungal genes from mycorrhizally colonized root tissue. Phylogenetic analysis revealed that the great majority of Cypripedium mycorrhizal fungi are members of narrow clades within the fungal family Tulasnellaceae. Rarely occurring root endophytes include members of the Sebacinaceae, Ceratobasidiaceae, and the ascomycetous genus, Phialophora. C. californicum was the only orchid species with apparently low specificity, as it associated with tulasnelloid, ceratobasidioid, and sebacinoid fungi in roughly equal proportion. Our results add support to the growing literature showing that high specificity is not limited to nonphotosynthetic plants, but also occurs in photosynthetic ones. [source]

The Neoliberalisation of the Local State in Durban, South Africa

ANTIPODE, Issue 2 2010
Sagie Narsiah
Abstract:, There exists a growing literature on the geographical aspects of neoliberalism and neoliberalisation. In this paper I focus on how the neoliberalisation process is articulated at the scale of the local state in Durban, South Africa. I examine the neoliberalisation process through the lens of the water sector. This paper contributes to the body of literature showing how private sector governance techniques are being used in the public sector effecting its neoliberalisation. I show how pricing structures are neoliberal and in turn how they are deployed and contribute to the neoliberalisation of the local state in Durban. I show that accounting strategies, tariff structures, and cost recovery measures are central to the neoliberalisation process in Durban. [source]

Acute hypertension reveals depressor and vasodilator effects of cannabinoids in conscious rats

BRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2009
W-S Vanessa Ho
Background and purpose:, The cardiovascular effects of cannabinoids can be influenced by anaesthesia and can differ in chronic hypertension, but the extent to which they are influenced by acute hypertension in conscious animals has not been determined. Experimental approach:, We examined cardiovascular responses to intravenous administration of anandamide and the synthetic cannabinoid, (R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone (WIN55212-2), in conscious male Wistar rats made acutely hypertensive by infusion of angiotensin II (AII) and arginine vasopressin (AVP). Rats were chronically instrumented for measurement of arterial blood pressure and vascular conductances in the renal, mesenteric and hindquarters beds. Key results:, Anandamide dose-dependently decreased the mean arterial blood pressure of rats made hypertensive by AII-AVP infusion, but not normotensive rats. Interestingly, acute hypertension also revealed a hypotensive response to WIN55212-2, which caused hypertension in normotensive animals. The enhanced depressor effects of the cannabinoids in acute hypertension were associated with increased vasodilatation in hindquarters, renal and mesenteric vascular beds. Treatment with URB597, which inhibits anandamide degradation by fatty acid amide hydrolase, potentiated the depressor and mesenteric vasodilator responses to anandamide. Furthermore, haemodynamic responses to WIN55212-2, but not to anandamide, were attenuated by the CB1 receptor antagonist, AM251 [N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophen yl)-4-methyl-1H-pyrazole-3-carboxamide]. Conclusions and implications:, These results broadly support the literature showing that the cardiovascular effects of cannabinoids can be exaggerated in hypertension, but highlight the involvement of non-CB1 receptor-mediated mechanisms in the actions of anandamide. [source]