2,687 research outputs found

    Grazing-incidence small-angle X-ray scattering studies on templating nanopores in networked polymer thin films with a multi-armed porogen

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    The mechanism of thermal pore generation in organosilicate thin films loaded with a six-armed star-shaped poly(epsilon-caprolactone) porogen was quantitatively investigated by using in-situ grazing-incidence small-angle X-ray scattering and thermogravimetry. These analyses found that the blend components have a limited miscibility that depends on the compositionfor porogen loadings up to only 20 wt%, molecularly miscible blend films were obtained. Even for the miscible blend films, heating the films produced a curing reaction of the precursor matrix component, leading to the phase separation of the porogen component. This phase separation was found to begin at 393 K for 10 wt% porogen loaded films and at 373 K for 20 wt% porogen loaded films, and to continue for temperatures up to 423 K. The porogen aggregates remained and were confined within the matrix film without any further growth or movement until complete thermal decomposition above 564 K.ope

    An FPTAS for Stochastic Unbounded Min-Knapsack Problem

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    In this paper, we study the stochastic unbounded min-knapsack problem (Min-SUKP\textbf{Min-SUKP}). The ordinary unbounded min-knapsack problem states that: There are nn types of items, and there is an infinite number of items of each type. The items of the same type have the same cost and weight. We want to choose a set of items such that the total weight is at least WW and the total cost is minimized. The \prob~generalizes the ordinary unbounded min-knapsack problem to the stochastic setting, where the weight of each item is a random variable following a known distribution and the items of the same type follow the same weight distribution. In \prob, different types of items may have different cost and weight distributions. In this paper, we provide an FPTAS for Min-SUKP\textbf{Min-SUKP}, i.e., the approximate value our algorithm computes is at most (1+ϵ)(1+\epsilon) times the optimum, and our algorithm runs in poly(1/ϵ,n,logW)poly(1/\epsilon,n,\log W) time.Comment: 24 page

    Leaf venation, as a resistor, to optimize a switchable IR absorber

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    Leaf vascular patterns are the mechanisms and mechanical support for the transportation of fluidics for photosynthesis and leaf development properties. Vascular hierarchical networks in leaves have far-reaching functions in optimal transport efficiency of functional fluidics. Embedding leaf morphogenesis as a resistor network is significant in the optimization of a translucent thermally functional material. This will enable regulation through pressure equalization by diminishing flow pressure variation. This paper investigates nature’s vasculature networks that exhibit hierarchical branching scaling applied to microfluidics. To enable optimum potential for pressure drop regulation by algorithm design. This code analysis of circuit conduit optimization for transport fluidic flow resistance is validated against CFD simulation, within a closed loop network. The paper will propose this self-optimization, characterization by resistance seeking targeting to determine a microfluidic network as a resistor. To advance a thermally function material as a switchable IR absorber

    The 'Harmonizing Optimal Strategy for Treatment of coronary artery stenosis - sAfety & effectiveneSS of drug-elUting stents & antiplatelet REgimen' (HOST-ASSURE) trial: study protocol for a randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Second-generation drug-eluting stents (DES) have raised the bar of clinical performance. These stents are mostly made from cobalt chromium alloy. A newer generation DES has been developed from platinum chromium alloy, but clinical data regarding the efficacy and safety of the platinum chromium-based everolimus-eluting stent (PtCr-EES) is limited, with no comparison data against the cobalt chromium-based zotarolimus-eluting stent (CoCr-ZES). In addition, an antiplatelet regimen is an integral component of medical therapy after percutaneous coronary intervention (PCI). A 1-week duration of doubling the dose of clopidogrel (double-dose antiplatelet therapy (DDAT)) was shown to improve outcome at 1 month compared with conventional dose in acute coronary syndrome (ACS) patients undergoing PCI. However in Asia, including Korea, the addition of cilostazol (triplet antiplatelet therapy (TAT)) is used more commonly than doubling the dose of clopidogrel in high-risk patients.</p> <p>Methods</p> <p>In the 'Harmonizing Optimal Strategy for Treatment of coronary artery stenosis - sAfety & effectiveneSS of drug-elUting stents & antiplatelet REgimen' (HOST-ASSURE) trial, approximately 3,750 patients are being prospectively and randomly assigned in a 2 × 2 factorial design according to the type of stent (PtCr-EES vs CoCr-ZES) and antiplatelet regimen (TAT vs DDAT). The first primary endpoint is target lesion failure at 1 year for the stent comparison, and the second primary endpoint is net clinical outcome at 1 month for comparison of antiplatelet therapy regimen.</p> <p>Discussion</p> <p>The HOST-ASSURE trial is the largest study yet performed to directly compare the efficacy and safety of the PtCr-EES versus CoCr-ZES in an 'all-comers' population. In addition, this study will also compare the clinical outcome of TAT versus DDAT for 1-month post PCI.</p> <p>Trial registration</p> <p>ClincalTrials.gov number <a href="http://www.clinicaltrials.gov/ct2/show/NCT01267734">NCT01267734</a>.</p

    Phytochemicals as antibiotic alternatives to promote growth and enhance host health

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    There are heightened concerns globally on emerging drug-resistant superbugs and the lack of new antibiotics for treating human and animal diseases. For the agricultural industry, there is an urgent need to develop strategies to replace antibiotics for food-producing animals, especially poultry and livestock. The 2nd International Symposium on Alternatives to Antibiotics was held at the World Organization for Animal Health in Paris, France, December 12-15, 2016 to discuss recent scientific developments on strategic antibiotic-free management plans, to evaluate regional differences in policies regarding the reduction of antibiotics in animal agriculture and to develop antibiotic alternatives to combat the global increase in antibiotic resistance. More than 270 participants from academia, government research institutions, regulatory agencies, and private animal industries from >25 different countries came together to discuss recent research and promising novel technologies that could provide alternatives to antibiotics for use in animal health and production; assess challenges associated with their commercialization; and devise actionable strategies to facilitate the development of alternatives to antibiotic growth promoters (AGPs) without hampering animal production. The 3-day meeting consisted of four scientific sessions including vaccines, microbial products, phytochemicals, immune-related products, and innovative drugs, chemicals and enzymes, followed by the last session on regulation and funding. Each session was followed by an expert panel discussion that included industry representatives and session speakers. The session on phytochemicals included talks describing recent research achievements, with examples of successful agricultural use of various phytochemicals as antibiotic alternatives and their mode of action in major agricultural animals (poultry, swine and ruminants). Scientists from industry and academia and government research institutes shared their experience in developing and applying potential antibiotic-alternative phytochemicals commercially to reduce AGPs and to develop a sustainable animal production system in the absence of antibiotics.Fil: Lillehoj, Hyun. United States Department of Agriculture. Agricultural Research Service; ArgentinaFil: Liu, Yanhong. University of California; Estados UnidosFil: Calsamiglia, Sergio. Universitat Autònoma de Barcelona; EspañaFil: Fernandez Miyakawa, Mariano Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Chi, Fang. Amlan International; Estados UnidosFil: Cravens, Ron L.. Amlan International; Estados UnidosFil: Oh, Sungtaek. United States Department of Agriculture. Agricultural Research Service; ArgentinaFil: Gay, Cyril G.. United States Department of Agriculture. Agricultural Research Service; Argentin

    Estimation of minimally important differences in EQ-5D utility and VAS scores in cancer

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    <p>Abstract</p> <p>Background</p> <p>Understanding what constitutes an important difference on a HRQL measure is critical to its interpretation. The aim of this study was to provide a range of estimates of minimally important differences (MIDs) in EQ-5D scores in cancer and to determine if estimates are comparable in lung cancer.</p> <p>Methods</p> <p>A retrospective analysis was conducted on cross-sectional data collected from 534 cancer patients, 50 of whom were lung cancer patients. A range of minimally important differences (MIDs) in EQ-5D index-based utility (UK and US) scores and VAS scores were estimated using both anchor-based and distribution-based (1/2 standard deviation and standard error of the measure) approaches. Groups were anchored using Eastern Cooperative Oncology Group performance status (PS) ratings and FACT-G total score-based quintiles.</p> <p>Results</p> <p>For UK-utility scores, MID estimates based on PS ranged from 0.10 to 0.12 both for all cancers and for lung cancer subgroup. Using FACT-G quintiles, MIDs were 0.09 to 0.10 for all cancers, and 0.07 to 0.08 for lung cancer. For US-utility scores, MIDs ranged from 0.07 to 0.09 grouped by PS for all cancers and for lung cancer; when based on FACT-G quintiles, MIDs were 0.06 to 0.07 in all cancers and 0.05 to 0.06 in lung cancer. MIDs for VAS scores were similar for lung and all cancers, ranging from 8 to 12 (PS) and 7 to 10 (FACT-G quintiles).</p> <p>Discussion</p> <p>Important differences in EQ-5D utility and VAS scores were similar for all cancers and lung cancer, with the lower end of the range of estimates closer to the MID, i.e. 0.08 for UK-index scores, 0.06 for US-index scores, and 0.07 for VAS scores.</p

    Differential interactions between IGFBP-3 and transforming growth factor-beta (TGF-β) in normal vs cancerous breast epithelial cells

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    In addition to modulating insulin-like growth factors action, it is now clear that insulin-like growth factor-binding protein-3 also has intrinsic effects on cell growth and survival. We have compared the effects of insulin-like growth factor-binding protein-3 and transforming growth factor-beta on cell proliferation and death of Hs578T cells and the normal breast epithelial cell line, MCF-10A. The growth of MCF-10A cells was inhibited at low concentrations of insulin-like growth factor-binding protein-3 but stimulated at high concentrations. These differential effects were unaffected in the presence of an insulin-like growth factor-I receptor antagonist. A synthetic peptide corresponding to the serine phosphorylation domain of insulin-like growth factor-binding protein-3 (that does not bind to insulin-like growth factors) also mimicked these differential actions. The growth of both cell lines was significantly inhibited by transforming growth factor-beta, this was associated with a 14-fold increase of insulin-like growth factor-binding protein-3 secreted by the Hs578T cells but a five-fold decrease of insulin-like growth factor-binding protein-3 secreted by MCF-10A cells. Replacement doses of exogenous insulin-like growth factor-binding protein-3 overcame the transforming growth factor-beta-induced growth inhibition in the MCF-10A cells. Cell death induced by ceramide was significantly reduced by insulin-like growth factor-binding protein-3 in the MCF-10A cells and depleting insulin-like growth factor-binding protein-3 with transforming growth factor-beta in these cells consequently increased their susceptibility to ceramide. In contrast, insulin-like growth factor-binding protein-3 enhanced apoptosis induced by ceramide in the Hs578T cells but transforming growth factor-beta treated Hs578T cells were resistant to apoptosis. The addition of anti-sense mRNA to insulin-like growth factor-binding protein-3 significantly abrogated this effect of transforming growth factor-beta. These data indicate that insulin-like growth factor-binding protein-3 has intrinsic activity capable of inhibiting or enhancing the growth and survival of breast epithelial cells depending on the cell line and exposure to other cytokines

    An unexpected evolution of symptomatic mild middle cerebral artery (MCA) stenosis: asymptomatic occlusion

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    <p>Abstract</p> <p>Background</p> <p>The intracranial localization of large artery disease is recognized as the main cause of ischemic stroke in the world, considering all countries, although its global burden is widely underestimated. Indeed it has been reported more frequently in Asians and African-American people, but the finding of intracranial stenosis as a cause of ischemic stroke is relatively common also in Caucasians. The prognosis of patients with stroke due to intracranial steno-occlusion is strictly dependent on the time of recanalization. Moreover, the course of the vessel involvement is highly dynamic in both directions, improvement or worsening, although several data are derived from the atherosclerotic subtype, compared to other causes.</p> <p>Case description</p> <p>We report the clinical, neurosonological and neuroradiological findings of a young woman, who came to our Stroke Unit because of the abrupt onset of aphasia during her work. An urgent neurosonological examination showed a left M1 MCA stenosis, congruent with the presenting symptoms; magnetic resonance imaging confirmed this finding and identified an acute ischemic lesion on the left MCA territory. The past history of the patient was significant only for a hyperinsulinemic condition, treated with metformine, and a mild overweight. At this time a selective cerebral angiography was not performed because of the patient refusal and she was discharged on antiplatelet and lipid-lowering therapy, having failed to identify autoimmune or inflammatory diseases. Within 1 month, she went back to our attention because of the recurrence of aphasia, lasting about ten minutes. Neuroimaging findings were unchanged, but the patient accepted to undergo a selective cerebral angiography, which showed a mild left distal M1 MCA stenosis.</p> <p>During the follow-up the patient did not experienced any recurrence, but a routine neurosonological examination found an unexpected evolution of the known MCA stenosis, i.e. left M1 MCA occlusion. Neuroradiological imaging did not identify new lesions of the brain parenchyma and a repeated selective cerebral angiography confirmed the left M1 MCA occlusion.</p> <p>Conclusions</p> <p>Regardless of the role of metabolic and/or inflammatory factors on the aetiology of the intracranial stenosis in this case, the course of the vessel disease was unexpected and previously unreported in the literature at our knowledge.</p

    Does the transcription factor AP-2β have an impact on the genetic and early environmental influence on ethanol consumption?

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    Genes involved in alcoholism have consensus sites for the transcription factor activator protein (TFAP) 2β. In the present study, we investigated TFAP-2β protein levels in the ethanol-preferring alko, alcohol (AA) and the ethanol-avoiding alko, non-alcohol (ANA) rat lines. Furthermore, basal and ethanol-induced TFAP-2β levels were examined in Wistar rats exposed to different early postnatal environments that are known to affect later ethanol consumption. Taken together, we found differences in brainstem TFAP-2β protein between the AA and ANA rats
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