2,899 research outputs found

    Big Data and Analysis of Data Transfers for International Research Networks Using NetSage

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    Modern science is increasingly data-driven and collaborative in nature. Many scientific disciplines, including genomics, high-energy physics, astronomy, and atmospheric science, produce petabytes of data that must be shared with collaborators all over the world. The National Science Foundation-supported International Research Network Connection (IRNC) links have been essential to enabling this collaboration, but as data sharing has increased, so has the amount of information being collected to understand network performance. New capabilities to measure and analyze the performance of international wide-area networks are essential to ensure end-users are able to take full advantage of such infrastructure for their big data applications. NetSage is a project to develop a unified, open, privacy-aware network measurement, and visualization service to address the needs of monitoring today's high-speed international research networks. NetSage collects data on both backbone links and exchange points, which can be as much as 1Tb per month. This puts a significant strain on hardware, not only in terms storage needs to hold multi-year historical data, but also in terms of processor and memory needs to analyze the data to understand network behaviors. This paper addresses the basic NetSage architecture, its current data collection and archiving approach, and details the constraints of dealing with this big data problem of handling vast amounts of monitoring data, while providing useful, extensible visualization to end users

    Structural characterisation of deposit layer during milk protein microfiltration by means of in-situ mri and compositional analysis

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    Milk protein fractionation by microfiltration membranes is an established but still growing field in dairy technology. Even under cross-flow conditions, this filtration process is impaired by the formation of a deposit by the retained protein fraction, mainly casein micelles. Due to deposition formation and consequently increased overall filtration resistance, the mass flow of the smaller whey protein fraction declines within the first few minutes of filtration. Currently, there are only a handful of analytical techniques available for the direct observation of deposit formation with opaque feed media and membranes. Here, we report on the ongoing development of a non-invasive and non-destructive method based on magnetic resonance imaging (MRI), and its application to characterise deposit layer formation during milk protein fractionation in ceramic hollow fibre membranes as a function of filtration pressure and temperature, temporally and spatially resolved. In addition, the chemical composition of the deposit was analysed by reversed phase high pressure liquid chromatography (RP-HPLC). We correlate the structural information gained by in-situ MRI with the protein amount and composition of the deposit layer obtained by RP-HPLC. We show that the combination of in-situ MRI and chemical analysis by RP-HPLC has the potential to allow for a better scientific understanding of the pressure and temperature dependence of deposit layer formation

    A TNF-őĪ Promoter Polymorphism Is Associated with Juvenile Onset Psoriasis and Psoriatic Arthritis

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    Tumor necrosis factor-őĪ is considered to be one of the important mediators in the pathogenesis of psoriasis. A strong association of juvenile onset psoriasis with the major histocompatibility complex encoded HLA-Cw6 antigen has been reported but it is unclear whether Cw6 itself or a closely linked gene is involved in the pathogenesis. This study has focused on the association of promoter polymorphisms of the major histocompatibility complex encoded tumor necrosis factor-őĪ gene with psoriasis and psoriatic arthritis. Tumor necrosis factor-őĪ promoter polymorphisms were sought by sequence-specific oligonucleotide hybridization and by direct sequencing in Caucasian patients with juvenile onset psoriasis and with psoriatic arthritis and in healthy controls. A mutation at position ‚ąí238 of the tumor necrosis factor-őĪ promoter was present in 23 of 60 patients (38%; p < 0.0001; Pcorr < 0.008) with juvenile onset psoriasis and in 20 of 62 patients (32%; p < 0.0003; Pcorr < 0.03) with psoriatic arthritis, compared with seven of 99 (7%) Caucasian controls. There was a marked increase of homozygotes for this mutation in the psoriasis group. Another mutation at position ‚ąí308 was found in similar proportions of patients and controls. Our study shows a strong association of the tumor necrosis factor-őĪ promoter polymorphism at position ‚ąí238 with psoriasis and psoriatic arthritis. Our findings suggest that this promoter polymorphism itself or a gene in linkage disequilibrium with tumor necrosis factor-őĪ predispose to the development of psoriasis

    Human helminth therapy to treat inflammatory disorders - where do we stand?

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    Parasitic helminths have evolved together with the mammalian immune system over many millennia and as such they have become remarkably efficient modulators in order to promote their own survival. Their ability to alter and/or suppress immune responses could be beneficial to the host by helping control excessive inflammatory responses and animal models and pre-clinical trials have all suggested a beneficial effect of helminth infections on inflammatory bowel conditions, MS, asthma and atopy. Thus, helminth therapy has been suggested as a possible treatment method for autoimmune and other inflammatory disorders in humans

    Panspermia, Past and Present: Astrophysical and Biophysical Conditions for the Dissemination of Life in Space

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    Astronomically, there are viable mechanisms for distributing organic material throughout the Milky Way. Biologically, the destructive effects of ultraviolet light and cosmic rays means that the majority of organisms arrive broken and dead on a new world. The likelihood of conventional forms of panspermia must therefore be considered low. However, the information content of dam-aged biological molecules might serve to seed new life (necropanspermia).Comment: Accepted for publication in Space Science Review

    The Kondo Effect in Non-Equilibrium Quantum Dots: Perturbative Renormalization Group

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    While the properties of the Kondo model in equilibrium are very well understood, much less is known for Kondo systems out of equilibrium. We study the properties of a quantum dot in the Kondo regime, when a large bias voltage V and/or a large magnetic field B is applied. Using the perturbative renormalization group generalized to stationary nonequilibrium situations, we calculate renormalized couplings, keeping their important energy dependence. We show that in a magnetic field the spin occupation of the quantum dot is non-thermal, being controlled by V and B in a complex way to be calculated by solving a quantum Boltzmann equation. We find that the well-known suppression of the Kondo effect at finite V>>T_K (Kondo temperature) is caused by inelastic dephasing processes induced by the current through the dot. We calculate the corresponding decoherence rate, which serves to cut off the RG flow usually well inside the perturbative regime (with possible exceptions). As a consequence, the differential conductance, the local magnetization, the spin relaxation rates and the local spectral function may be calculated for large V,B >> T_K in a controlled way.Comment: 9 pages, invited paper for a special edition of JPSJ "Kondo Effect -- 40 Years after the Discovery", some typos correcte

    √Čpocas de desseca√ß√£o nos atributos p√≥s-colheita de gr√£os de soja.

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    Resumo: Visando aumentar a janela de plantio da segunda safra, a aplica√ß√£o de herbicida dessecante na lavoura de soja antes da matura√ß√£o fisiol√≥gica dos gr√£os tem sido pr√°tica comum no m√©dio norte de Mato Grosso, por parte dos produtores. Assim, objetivou-se, por meio deste trabalho, avaliar o efeito da aplica√ß√£o de dessecante em diferentes est√°dios fenol√≥gicos da lavoura de soja nos aspectos f√≠sicos e qu√≠micos dos gr√£os, em Sinop-MT, durante a safra da soja 2018/19. As cultivares BRS 7980 e M 8372 IPRO foram dessecadas em cinco est√°dios fenol√≥gicos distintos (R5.5, R6, R7.1, R7.3, R8.1). Ap√≥s a colheita, os gr√£os foram secos, limpos e classificados. Em seguida, determinou-se a massa espec√≠fica aparente, a massa de mil gr√£os e os componentes de composi√ß√£o centesimal (fibra bruta, extrato et√©reo, prote√≠na, cinzas, carboidrato e √°gua). A antecipa√ß√£o da desseca√ß√£o reduziu a massa de mil gr√£os, aumentou a massa espec√≠fica aparente e diminuiu a quantidade de √≥leo nos gr√£os. A aplica√ß√£o do herbicida dessecante no est√°dio recomendado reduziu as inj√ļrias causadas por pat√≥genos nos gr√£os de soja das duas cultivares. | Abstract: In order to increase the planting window of the second crop, some producers have used an application of desiccant herbicide before physiological maturation of soybeans in the middle northern of Mato Grosso. The objective of this work was to evaluate the effect of desiccant application at different stages of maturation of soybean crops, and to evaluate the influence of this operation on physical and chemical aspects of the grains. We used grains from cultivars BRS 7980 and M 8372 IPRO. For each cultivar evaluated, desiccation occurred in five phenological stages (R5.5, R6, R7.1, R7.3, R8.1). After harvesting, the beans were dried, cleaned and classified. The anticipation of desiccation reduced the mass of a thousand grains, increased the apparent specific mass and decreased the amount of oil in the grains. The application of the desiccant herbicide at the recommended stage reduced the deterioration of the grains in the field, caused by pathogens

    Habitable Zones in the Universe

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    Habitability varies dramatically with location and time in the universe. This was recognized centuries ago, but it was only in the last few decades that astronomers began to systematize the study of habitability. The introduction of the concept of the habitable zone was key to progress in this area. The habitable zone concept was first applied to the space around a star, now called the Circumstellar Habitable Zone. Recently, other, vastly broader, habitable zones have been proposed. We review the historical development of the concept of habitable zones and the present state of the research. We also suggest ways to make progress on each of the habitable zones and to unify them into a single concept encompassing the entire universe.Comment: 71 pages, 3 figures, 1 table; to be published in Origins of Life and Evolution of Biospheres; table slightly revise
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