573 research outputs found

    Role of Age in Mitochondrial Susceptibility to 1,3-Dinitrobenzene-Induced Neurotoxicity.

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    The prevalence of neurodegenerative disease is projected to increase in proportion to the doubling of older Americans over the coming decades. While age is the principle epidemiologic factor, it is likely that the development of these complex neuropathological entities is multifactorial and reflects the accumulation of chemical, physical and/or biological insults to the CNS. The Superfund chemical, 1,3-Dinitrobenzene (DNB), is an industrial intermediate in the production of dyes, plastics, and explosives. DNB selectively targets astrocytes in brainstem nuclei innervated by the 8th cranial nerve. The toxicity of DNB has been previously linked to dysfunction in astrocyte mitochondria. This study focuses on the susceptibility of key mitochondrial proteins to selective and specific oxidation following exposure to DNB in vitro and in vivo. Using an immortalized cortical astrocyte culture, passage number provided a useful surrogate for age in vitro. In a co-culture system containing immortalized astrocytes and primary neurons, low passage immortalized astrocytes are able to protect neurons in DNB exposure (whereas high passage immortalized astrocytes are not); additionally, low passage immortalized astrocytes are better able to survive DNB exposure in co-culture than high passage immortalized astrocytes. Additionally, in vivo data shows that proteins in older mitochondria are more susceptible to oxidation by DNB than the ones from young organelles, and mitochondria-related proteins are more highly expressed in young control animals than in older animals (both control and DNB-exposed). This data suggests that aging increases mitochondrial susceptibility to DNB-induced neurotoxicity. Using a high throughput proteomic approach with subsequent pathway analysis, it was determined that cation transmembrane transporter, nucleoside-triphosphatase, pyrophosphatase, and hydrolase activity pathways are selectively vulnerable to oxidation in older mitochondria. These results provide compelling evidence that environmental chemicals such as DNB may aid in the acceleration of injury to specific brain regions by inducing oxidation of sensitive mitochondrial proteins.PhDToxicologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/108896/1/lauramau_1.pd

    Morphological Description of Telaepolella tubasferens n. g., n. sp., Isolate ATCC© 50593™, a Filose Amoeba in the Gracilipodida, Amoebozoa

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    We describe the amoeboid isolate ATCC© 50593™ as a new taxon, Telaepolella tubasferens n. gen. n. sp. This multinucleated amoeba has filose pseudopods and is superficially similar to members of the vampyrellids (Rhizaria) such as Arachnula impatiens Cienkowski, 1876, which was the original identification upon deposition. However, previous multigene analyses place this taxon within the Gracilipodida Lahr and Katz 2011 in the Amoebozoa. Here, we document the morphology of this organism at multiple life history stages and describe data underlying the description as a new taxon. We demonstrate that T. tubaspherens is distinct from Arachnula and other rhizarians (Theratromyxa, Leptophrys) in a suite of morphological characters such as general body shape, relative size of pseudopods, distinction of ecto- and endoplasmic regions, and visibility of nuclei in non-stained cells (an important diagnostic character). Although Amoebozoa taxa generally have lobose pseudopods, genera in Gracilipodida such as Flamella and Filamoeba as well as several organisms previously classified as protosteloid amoebae (e.g. schizoplasmodiis, cavosteliids and Stemonitales) present filose pseudopodia. Thus, classification of amoeboid organisms merely by filose-lobose distinction must be reconsidered

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

    Search for stop and higgsino production using diphoton Higgs boson decays

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    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

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    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

    Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

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    Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia

    Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

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    A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV
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