10,402 research outputs found
Circulating Subbeam Systems and the Physics of Pulsar Emission
The purpose of this paper is to suggest how detailed single-pulse
observations of ``slow'' radio pulsars may be utilized to construct an
empirical model for their emission. It links the observational synthesis
developed in a series of papers by Rankin starting in the 1980s to the more
recent empirical feedback model of Wright (2003a) by regarding the entire
pulsar magnetosphere as a non-steady, non-linear interactive system with a
natural built-in delay. It is argued that the enhanced role of the outer gap in
such a system indicates an evolutionary link to younger pulsars, in which this
region is thought to be highly active, and that pulsar magnetospheres should no
longer be seen as being ``driven'' by events on the neutron star's polar cap,
but as having more in common with planetary magnetospheres and auroral
phenomena.Comment: 15 pages, 3 figure
An Analytic Comparative Study of Certain Biology Textbooks Used At Secondary School Level
The specific problem of this the sis is An Analytic Comparative Study of Certain Biology Textbooks Used at the Secondary School Level
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White coat hypertension is associated with increased small vessel disease in the brain
Objective:
Small vessel disease, as measured by white matter hyperintensity (WMH) in the brain, is known to be associated with increased stroke risk and cognitive impairment. This study explored the relationship between WMH on computerised tomography (CT) and white coat hypertension/effect (WCH/E) in patients with recent transient ischaemic attack (TIA) or lacunar stroke (LS).
Design and method:
Ninety-six patients recruited for the ASIST trial (Arterial Stiffness in Lacunar Stroke and TIA) underwent measurement of clinic blood pressure (BP) and ambulatory BP monitoring (APBM) within two weeks of TIA or LS. Twenty-three patients had normotension (clinic BP / = 140/90mmHg and day-time ABPM < 135/85mmHg). Arterial stiffness was measured using carotid-femoral pulse wave velocity (PWV) (CompliorÂź, ALAM Medical) and carotid-ankle vascular index (CAVI) (VaSera VS-1500NÂź, Fukuda Denshi). CT images were scored for WMH using the four-point Fazekas visual rating scale. Patients were grouped into no-mild WMH (scores 0â1) or moderate-severe (scores 2â3) groups. The relationship between BP, vascular stiffness and WMH was explored with t-tests, chi-square and logistic regression accounting for known cardiovascular risk factors.
Results:
Forty-four percent of patients with WCH/E had moderate-severe WMH compared to 17% of normotensives (p = 0.047). The regression model with WMH as the dependent factor, and WCH/E and cardiovascular risk factors as independent factors showed WCH/E and either CAVI or PWV to be the only independent significant factor contributing to WMH (CAVI:p = 0.038, PWV:p = 0.043)
Experiencing Nothing: Anxiety and the Philosophy of Alain Badiou
This thesis proposes to supplement the philosophy of Alain Badiou with an existentialist account of anxiety. After identifying a âphenomenological deficitâ in Badiouâs thought, I argue that Kierkegaard, Heidegger, and Sartre provide the conceptual resources for theorizing the affective emergence of subjectivity from within the confines of a determinant situation. My contention, simply, is that anxiety is a rare and unsettling experience of nothing that makes apparent the underlying contingency of all situations, thereby prompting new modes of subjective behavior. In this sense, I treat anxiety as the in-situation experience of an event that may occasion the transition from a determined-individual to a determining-subject
Sustainability Strategies in U.S. Agribusiness: Understanding Key Drivers, Objectives, and Actions
sustainability, triple bottom line, strategy, stakeholders, supply chain, Agribusiness, Demand and Price Analysis, Environmental Economics and Policy, Production Economics, Productivity Analysis, Risk and Uncertainty,
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