98 research outputs found

    Appalachian Baptism: The Asheville Flood Of 1916

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    The Southern Appalachian flood of 1916 was no act of God. The actions of a few powerful white men added to the severity of the disaster. It ignited broad social discord and challenged the hegemony of Asheville’s elites. The socio-economic priorities of city leaders shifted. Tourism received the full support of Asheville’s government leaders as river-based industries declined. As a result, hundreds of laborers, both black and white, lost their jobs, homes, and places in society. This story is about class, race, and the rise of industrial capitalism in America. It also adds to historiography detailed analysis of the natural disasters that shaped regional societies.In 1916, Asheville boasted a balanced economy supported by industrial pursuits. Yet, by the 1930s, Asheville suffered immensely during the Great Depression because of that period of unwarranted speculation from which the city never recovered. This study discusses the futility of the belief in the boundless potential of the environment, wealth, and social power structures in early twentieth century capitalist societies. Asheville’s leaders responded conservatively to the flood, which led to further marginalization of vulnerable segments of the population and industries

    Psychophysiological correlates of voluntary alpha control

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    To test the hypothesis that voluntary alpha control is at least partly mediated through self-induced changes in cortical activation level and bodily arousal, changes in several physiological indicants of such activity were systematically examined while subjects voluntarily produced and suppressed alpha activity. Physiological indicants consisted of cortical evoked potentials, eye motor activity, neck EMG, and skin conductance. Three male and three female subjects were pretrained to a specified criterion to produce and suppress alpha activity, using auditory feedback. Following pretraining, each subject participated in four experimental sessions under instructions to either produce or suppress alpha while keeping his eyes closed. Each session consisted of eight alternating three-minute trials of high and low alpha conditions with rest intervals between trials. During each session EEG activity was recorded monopolarly from the occiput with the reference electrode on the right earlobe. Filtered, integrated EEG consisting of alpha activity only, drove a frequency- modulated power driver connected to a speaker which provided continuous feedback in terms of the pitch of a tone. Cortical evoked potentials based on the presentation of 100 irregularly presented light flashes per trial were recorded with a Computer of Average Transients. Using the appropriate Grass Model 7 preamplifiers, skin conductance was recorded from the first and third fingers of the left hand; EMG from the trapezius neck muscle, and eye motor activity with electrodes placed diagonally across the eyes

    Arousal level and voluntary alpha control

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    To examine the influence of arousal level on subjects' ability to voluntarily control alpha activity level, loud unpleasant noises were presented at random intervals. The effect of this aversive stimulus situation on alpha activity level relative to no noise was examined while subjects attempted to enhance or suppress alpha activity in both eyes-open and eyes-closed conditions. The eight subjects were pretrained to a specified criterion of alpha control before participating in the four experimental sessions. In addition to recordings of the EEG alpha activity, concurrent measures of neck EMG activity and heart rate were also obtained to provide information concerning general somatic arousal during the various experimental conditions. The results indicated that the strength and direction of the interrelationships of the physiological variables—heart rate, EMG, and alpha level—were dependent on whether the eyes were open or closed. The failure to demonstrate a relationship between alpha level and a subjectively aversive situation was discussed as possibly being dependent on the nature of the biofeedback control of alpha

    Habitat Composition and Connectivity Predicts Bat Presence and Activity at Foraging Sites in a Large UK Conurbation

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    Background: Urbanization is characterized by high levels of sealed land-cover, and small, geometrically complex, fragmented land-use patches. The extent and density of urbanized land-use is increasing, with implications for habitat quality, connectivity and city ecology. Little is known about densification thresholds for urban ecosystem function, and the response of mammals, nocturnal and cryptic taxa are poorly studied in this respect. Bats (Chiroptera) are sensitive to changing urban form at a species, guild and community level, so are ideal model organisms for analyses of this nature. Methodology/Principal Findings: We surveyed bats around urban ponds in the West Midlands conurbation, United Kingdom (UK). Sites were stratified between five urban land classes, representing a gradient of built land-cover at the 1 km 2 scale. Models for bat presence and activity were developed using land-cover and land-use data from multiple radii around each pond. Structural connectivity of tree networks was used as an indicator of the functional connectivity between habitats. All species were sensitive to measures of urban density. Some were also sensitive to landscape composition and structural connectivity at different spatial scales. These results represent new findings for an urban area. The activity of Pipistrellus pipistrellus (Schreber 1774) exhibited a non-linear relationship with the area of built land-cover, being much reduced beyond the threshold of,60 % built surface. The presence of tree networks appears to mitigate the negative effects of urbanization for this species

    Mechanical Influences on Morphogenesis of the Knee Joint Revealed through Morphological, Molecular and Computational Analysis of Immobilised Embryos

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    Very little is known about the regulation of morphogenesis in synovial joints. Mechanical forces generated from muscle contractions are required for normal development of several aspects of normal skeletogenesis. Here we show that biophysical stimuli generated by muscle contractions impact multiple events during chick knee joint morphogenesis influencing differential growth of the skeletal rudiment epiphyses and patterning of the emerging tissues in the joint interzone. Immobilisation of chick embryos was achieved through treatment with the neuromuscular blocking agent Decamethonium Bromide. The effects on development of the knee joint were examined using a combination of computational modelling to predict alterations in biophysical stimuli, detailed morphometric analysis of 3D digital representations, cell proliferation assays and in situ hybridisation to examine the expression of a selected panel of genes known to regulate joint development. This work revealed the precise changes to shape, particularly in the distal femur, that occur in an altered mechanical environment, corresponding to predicted changes in the spatial and dynamic patterns of mechanical stimuli and region specific changes in cell proliferation rates. In addition, we show altered patterning of the emerging tissues of the joint interzone with the loss of clearly defined and organised cell territories revealed by loss of characteristic interzone gene expression and abnormal expression of cartilage markers. This work shows that local dynamic patterns of biophysical stimuli generated from muscle contractions in the embryo act as a source of positional information guiding patterning and morphogenesis of the developing knee joint

    The Effects of Sleep Hypoxia on Coagulant Factors and Hepatic Inflammation in Emphysematous Rats

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    OBJECTIVES: To develop a sleep hypoxia (SH) in emphysema (SHE) rat model and to explore whether SHE results in more severe hepatic inflammation than emphysema alone and whether the inflammation changes levels of coagulant/anticoagulant factors synthesized in the liver. METHODS: Seventy-five rats were put into 5 groups: SH control (SHCtrl), treated with sham smoke exposure (16 weeks) and SH exposure (12.5% O(2), 3 h/d, latter 8 weeks); emphysema control (ECtrl), smoke exposure and sham SH exposure (21% O(2)); short SHE (SHEShort), smoke exposure and short SH exposure (1.5 h/d); mild SHE (SHEMild), smoke exposure and mild SH exposure (15% O(2)); standard SHE (SHEStand), smoke exposure and SH exposure. Therefore, ECtrl, SHEShort, SHEMild and SHEStand group were among emphysematous groups. Arterial blood gas (ABG) data was obtained during preliminary tests. After exposure, hepatic inflammation (interleukin -6 [IL-6] mRNA and protein, tumor necrosis factor α [TNFα] mRNA and protein) and liver coagulant/anticoagulant factors (antithrombin [AT], fibrinogen [FIB] and Factor VIII [F VIII]) were evaluated. SPSS 11.5 software was used for statistical analysis. RESULTS: Characteristics of emphysema were obvious in emphysematous groups and ABGs reached SH criteria on hypoxia exposure. Hepatic inflammation parameters and coagulant factors are the lowest in SHCtrl and the highest in SHEStand while AT is the highest in SHCtrl and the lowest in SHEStand. Inflammatory cytokines of liver correlate well with coagulant factors positively and with AT negatively. CONCLUSIONS: When SH is combined with emphysema, hepatic inflammation and coagulability enhance each other synergistically and produce a more significant liver-derivative inflammatory and prothrombotic status

    β-Adrenoreceptor Stimulation Mediates Reconsolidation of Social Reward-Related Memories

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    In recent years, the notion that consolidated memories become transiently unstable after retrieval and require reconsolidation to persist for later use has received strong experimental support. To date, the majority of studies on reconsolidation have focused on memories of negative emotions, while the dynamics of positive memories have been less well studied. Social play, the most characteristic social behavior displayed by young mammals, is important for social and cognitive development. It has strong rewarding properties, illustrated by the fact that it can induce conditioned place preference (CPP). In order to understand the dynamics of positive social memories, we evaluated the effect of propranolol, a β-adrenoreceptor antagonist known to influence a variety of memory processes, on acquisition, consolidation, retrieval and reconsolidation of social play-induced CPP in adolescent rats.Systemic treatment with propranolol, immediately before or after a CPP test (i.e. retrieval session), attenuated CPP 24 h later. Following extinction, CPP could be reinstated in saline--but not in propranolol-treated rats, indicating that propranolol treatment had persistently disrupted the CPP memory trace. Propranolol did not affect social play-induced CPP in the absence of memory retrieval or when administered 1 h or 6 h after retrieval. Furthermore, propranolol did not affect acquisition, consolidation or retrieval of social play-induced CPP.We conclude that β-adrenergic neurotransmission selectively mediates the reconsolidation, but not other processes involved in the storage and stability of social reward-related memories in adolescent rats. These data support the notion that consolidation and reconsolidation of social reward-related memories in adolescent rats rely on distinct neural mechanisms

    A meta-analysis of the relationship between brain dopamine receptors and obesity: a matter of changes in behavior rather than food addiction?

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    Addiction to a wide range of substances of abuse has been suggested to reflect a ‘Reward Deficiency Syndrome'. That is, drugs are said to stimulate the reward mechanisms so intensely that, to compensate, the population of dopamine D(2) receptors (DD2R) declines. The result is that an increased intake is necessary to experience the same degree of reward. Without an additional intake, cravings and withdrawal symptoms result. A suggestion is that food addiction, in a similar manner to drugs of abuse, decrease DD2R. The role of DD2R in obesity was therefore examined by examining the association between body mass index (BMI) and the Taq1A polymorphism, as the A1 allele is associated with a 30–40% lower number of DD2R, and is a risk factor for drug addiction. If a lower density of DD2R is indicative of physical addiction, it was argued that if food addiction occurs, those with the A1 allele should have a higher BMI. A systematic review found 33 studies that compared the BMI of those who did and did not have the A1 allele. A meta-analysis of the studies compared those with (A1/A1 and A1/A2) or without (A2/A2) the A1 allele; no difference in BMI was found (standardized mean difference 0.004 (s.e. 0.021), variance 0.000, Z=0.196, P<0.845). It was concluded that there was no support for a reward deficiency theory of food addiction. In contrast, there are several reports that those with the A1 allele are less able to benefit from an intervention that aimed to reduce weight, possibly a reflection of increased impulsivity
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