2,804 research outputs found
Agriculture and poverty in the Kentucky mountains: Beech Creek and Clay County, 1850-1910
The poverty of Appalachia is not the product of modernization. Nor is it a unique phenomenon. An examination of the history of farming in Beech Creek, Kentucky, reveals that this community, which was prosperous in 1860, owed its fall into poverty to a number of factors that had impoverished other regions: the high rate of population growth among the families living in the area, the division and re-division of the limited land to accommodate the new generations of families, the need to use woodland for agriculture before reforestation succeeded in restoring the old soil to its original productivity, and slow economic growth resulting from the emphasis on subsistence rather than commercial agriculture. The same pattern had occurred in New England in the eighteenth century. What was unique in Appalachia was that subsistence farming lasted so long, owing to growing isolation from the rest of the country as the area was bypassed in the construction of modern means of transportation.
Dynamical epidemic suppression using stochastic prediction and control
We consider the effects of noise on a model of epidemic outbreaks, where the
outbreaks appear. randomly. Using a constructive transition approach that
predicts large outbreaks, prior to their occurrence, we derive an adaptive
control. scheme that prevents large outbreaks from occurring. The theory
inapplicable to a wide range of stochastic processes with underlying
deterministic structure.Comment: 14 pages, 6 figure
A Coronal Hole's Effects on CME Shock Morphology in the Inner Heliosphere
We use STEREO imagery to study the morphology of a shock driven by a fast
coronal mass ejection (CME) launched from the Sun on 2011 March 7. The source
region of the CME is located just to the east of a coronal hole. The CME ejecta
is deflected away from the hole, in contrast with the shock, which readily
expands into the fast outflow from the coronal hole. The result is a CME with
ejecta not well centered within the shock surrounding it. The shock shape
inferred from the imaging is compared with in situ data at 1 AU, where the
shock is observed near Earth by the Wind spacecraft, and at STEREO-A. Shock
normals computed from the in situ data are consistent with the shock morphology
inferred from imaging.Comment: to appear in The Astrophysical Journa
Coenzyme Q10 dose-escalation study in hemodialysis patients: safety, tolerability, and effect on oxidative stress.
BackgroundCoenzyme Q10 (CoQ10) supplementation improves mitochondrial coupling of respiration to oxidative phosphorylation, decreases superoxide production in endothelial cells, and may improve functional cardiac capacity in patients with congestive heart failure. There are no studies evaluating the safety, tolerability and efficacy of varying doses of CoQ10 in chronic hemodialysis patients, a population subject to increased oxidative stress.MethodsWe performed a dose escalation study to test the hypothesis that CoQ10 therapy is safe, well-tolerated, and improves biomarkers of oxidative stress in patients receiving hemodialysis therapy. Plasma concentrations of F2-isoprostanes and isofurans were measured to assess systemic oxidative stress and plasma CoQ10 concentrations were measured to determine dose, concentration and response relationships.ResultsFifteen of the 20 subjects completed the entire dose escalation sequence. Mean CoQ10 levels increased in a linear fashion from 704 Ā± 286 ng/mL at baseline to 4033 Ā± 1637 ng/mL, and plasma isofuran concentrations decreased from 141 Ā± 67.5 pg/mL at baseline to 72.2 Ā± 37.5 pg/mL at the completion of the study (P = 0.003 vs. baseline and P < 0.001 for the effect of dose escalation on isofurans). Plasma F2-isoprostane concentrations did not change during the study.ConclusionsCoQ10 supplementation at doses as high as 1800 mg per day was safe in all subjects and well-tolerated in most. Short-term daily CoQ10 supplementation decreased plasma isofuran concentrations in a dose dependent manner. CoQ10 supplementation may improve mitochondrial function and decrease oxidative stress in patients receiving hemodialysis.Trial registrationThis clinical trial was registered on clinicaltrials.gov [NCT00908297] on May 21, 2009
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C/EBP Transcription Factors in Human Squamous Cell Carcinoma: Selective Changes in Expression of Isoforms Correlate with the Neoplastic State
The CCAAT/Enhancer Binding Proteins (C/EBPs) are a family of leucine-zipper transcription factors that regulate physiological processes such as energy metabolism, inflammation, cell cycle, and the development and differentiation of several tissues including skin. Recently, a role for C/EBPs in tumor cell proliferation and differentiation has been proposed, but the incomplete characterization in the literature of multiple translational isoforms of these proteins has made interpretation of these roles difficult. Therefore, we have carefully reexamined C/EBP isoform expression in human non-melanoma skin cancers. C/EBPĪ±, C/EBPĪ², and C/EBPĪ“ were analyzed histologically in squamous cell carcinomas (SCC). The individual isoforms of C/EBPĪ± and C/EBPĪ² were examined by immunofluorescent digital imaging, western blotting and DNA binding activity (electrophoretic mobility shift analysis). Expression of all C/EBP family proteins was decreased in SCC tumors. Suppression was greatest for C/EBPĪ±, less for C/EBPĪ², and least for C/EBPĪ“. Western analyses confirmed that C/EBPĪ± p42 and p30 isoforms were decreased. For C/EBPĪ², only the abundant full-length isoform (C/EBPĪ²ā1, LAP*, 55 kD) was reduced, whereas the smaller isoforms, C/EBPĪ²ā2 (LAP, 48 kD) and C/EBPĪ²ā3 (LIP, 20 kD), which are predominantly nuclear, were significantly increased in well- and moderately-differentiated SCC (up to 14-fold for C/EBPĪ²ā3). These elevations correlated with increases in PCNA, a marker of proliferation. Although C/EBPĪ² displayed increased post-translational modifications in SCC, phosphorylation of C/EBPĪ²ā1 (Thr 235) was not altered. C/EBP-specific DNA binding activity in nuclear and whole-cell extracts of cultured cells and tumors was predominantly attributable to C/EBPĪ². In summary, two short C/EBPĪ² isoforms, C/EBPĪ²ā2 and C/EBPĪ²ā3, represent strong candidate markers for epithelial skin malignancy, due to their preferential expression in carcinoma versus normal skin, and their strong correlation with tumor proliferation
Gene Correction Reduces Cutaneous Inflammation and Granuloma Formation in Murine X-Linked Chronic Granulomatous Disease
Our laboratory previously demonstrated that X-linked chronic granulomatous disease (X-CGD) mice develop exaggerated inflammatory responses and form granulomas following intradermal challenge with sterile Aspergillus fumigatus (AF) hyphae. In this study, we examined the efficacy of retroviral-mediated gene transfer (RMGT) into X-CGD bone marrow stem cells in preventing this abnormal inflammatory response. Sterile AF or saline was injected subcutaneously into the ears of wild-type, female X-CGD carrier, X-CGD, or X-CGD mice chimeric for varying numbers of either wild-type or RMGT-corrected neutrophils. Intradermal AF induced marked inflammation at both 3 and 30 d in the X-CGD mice, but not in the carriers or the wild-type mice. Similar to wild-type mice, chimeric X-CGD mice with >20% oxidase-positive neutrophils displayed a minimal and self-limited inflammatory response. Inflammation in chimeric (both wild-type and RMGT-corrected) mice with <15% oxidase-positive neutrophils was also improved compared to X-CGD mice, although still abnormal. This is the first evidence that partial correction of NADPH oxidase activity by gene therapy is likely to be beneficial in reducing or preventing the chronic inflammatory complications of CGD patients if sufficient numbers of RMGT-corrected neutrophils are obtained
Critical Race Theory and Education: racism and anti-racism in educational theory and praxis
What is Critical Race Theory (CRT) and what does it offer educational researchers and practitioners outside the US? This paper addresses these questions by examining the recent history of antiracist research and policy in the UK. In particular, the paper argues that conventional forms of antiracism have proven unable to keep pace with the development of increasingly racist and exclusionary education polices that operate beneath a veneer of professed tolerance and diversity. In particular, contemporary antiracism lacks clear statements of principle and theory that risk reinventing the wheel with each new study; it is increasingly reduced to a meaningless slogan; and it risks appropriation within a reformist ācan doā perspective dominated by the de-politicized and managerialist language of school effectiveness and improvement. In contrast, CRT offers a genuinely radical and coherent set of approaches that could revitalize critical research in education across a range of inquiries, not only in self-consciously "multicultural" studies. The paper reviews the developing terrain of CRT in education, identifying its key defining elements and the conceptual tools that characterise the work. CRT in education is a fast changing and incomplete project but it can no longer be ignored by the academy beyond North America
A Simple Iterative Algorithm for Parsimonious Binary Kernel Fisher Discrimination
By applying recent results in optimization theory variously known as optimization transfer or majorize/minimize algorithms, an algorithm for binary, kernel, Fisher discriminant analysis is introduced that makes use of a non-smooth penalty on the coefficients to provide a parsimonious solution. The problem is converted into a smooth optimization that can be solved iteratively with no greater overhead than iteratively re-weighted least-squares. The result is simple, easily programmed and is shown to perform, in terms of both accuracy and parsimony, as well as or better than a number of leading machine learning algorithms on two well-studied and substantial benchmarks
L'ombre de l'empire: les rapports de la Roumanie Ć la Russie, 1991-2006
The aim of this article is to analyze the bilateral relations between Romania and the Russian Federation from the dismantlement of the USSR until the accession of Romania to the European Union. The main thesis that we shall try to demonstrate is that, for several reasons, these relations remained very ambiguous during this whole period. One the one hand, there are historical causes of a strong russophobia among the Romanian population, which prevented a rapprochement between the two countries after the fall of communism. On the other hand, Russia's prestige as a great power and its proximity to Romania makes it impossible to ignore when it comes to foreign policy. The position of the different Romanian governments oscillated between these two negative attitudes. We shall try to explain the policy conducted by the Romanian decision-makers by using three types of variables: history, domestic politics and international environment
Building a no limit Texas hold'em poker agent based on game logs using supervised learning
The development of competitive artificial Poker players is a challenge to Artificial Intelligence (AI) because the agent must deal with unreliable information and deception which make it essential to model the opponents to achieve good results. In this paper we propose the creation of an artificial Poker player through the analysis of past games between human players, with money involved. To accomplish this goal, we defined a classification problem that associates a given game state with the action that was performed by the player. To validate and test the defined player model, an agent that follows the learned tactic was created. The agent approximately follows the tactics from the human players, thus validating this model. However, this approach alone is insufficient to create a competitive agent, as generated strategies are static, meaning that they can't adapt to different situations. To solve this problem, we created an agent that uses a strategy that combines several tactics from different players. By using the combined strategy, the agentgreatly improved its performance against adversaries capable of modeling opponents
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