2,197 research outputs found
Genetic variation at major histocompatibility complex loci in Neotoma albigula (white-throated woodrat) potential clues to the evolution of North American arenaviruses.
The major histocompatibility complex Mhc is an important component of vertebrate immune systems, and as such, genetic analysis of Mhc loci have been shown to provide information on susceptibility to viral infection. Neotoma albigula (white-throated woodrat) are naturally associated with at least 3 arenaviruses, and are considered the putative host species for all 3 viruses. Strains of arenaviruses can cause severe febrile diseases in humans and are considered a serious health risk where human-rodent interactions are common. The association of N. albigula with at least 3 viruses suggests a significant co-evolutionary history between the host and virus. In this study, Mhc loci were screened to detect genetic variation among N. albigula populations in Arizona. This was done to test the prediction that levels of genetic variation at Mhc loci in N. albigula will correlate with specific arenaviral strains. The results have indicated moderate genetic variation among groups but almost no correlation with viral data.--Abstract
Subgap anomaly and above-energy-gap structure in chains of diffusive SNS junctions
We present the results of low-temperature transport measurements on chains of
superconductor--normal-constriction--superconductor (SNS) junctions fabricated
on the basis of superconducting PtSi film. A comparative study of the
properties of the chains, consisting of 3 and 20 SNS junctions in series, and
single SNS junctions reveals essential distinctions in the behavior of the
current-voltage characteristics of the systems: (i) the gradual decrease of the
effective suppression voltage for the excess conductivity observed at zero bias
as the quantity of the SNS junctions increases, (ii) a rich fine structure on
the dependences dV/dI-V at dc bias voltages higher than the superconducting gap
and corresponding to some multiples of 2\Delta/e. A model to explain this
above-energy-gap structure based on energy relaxation of electron via
Cooper-pair-breaking in superconducting island connecting normal metal
electrods is proposed.Comment: RevTex, 5 pages, 4 figure
Valorization of wine‐making by‐products’ extracts in cosmetics
The increased demand for conscious, sustainable and beneficial products by the consumers has pushed researchers from both industries and universities worldwide to search for smart strategies capable of reducing the environmental footprint, especially the ones connected with industrial wastes. Among various by-products, generally considered as waste, those obtained by winemaking industries have attracted the attention of a wide variety of companies, other than the vineries. In particular, grape pomaces are considered of interest due to their high content in bioactive molecules, especially phenolic compounds. The latter can be recovered from grape pomace and used as active ingredients in easily marketable cosmetic products. Indeed, phenolic compounds are well known for their remarkable beneficial properties at the skin level, such as antioxidant, antiaging, anti-hyperpigmentation and photoprotective effects. The exploitation of the bioactives contained in grape pomaces to obtain high value cosmetics may support the growing of innovative start-ups and expand the value chain of grapes. This review aims to describe the strategies for recovery of polyphenols from grape pomace, to highlight the beneficial potential of these extracts, both in vitro and in vivo, and their potential utilization as active ingredients in cosmetic products
Reference standardization and triglyceride interference of a new homogeneous HDL-cholesterol assay compared with a former chemical precipitation assay
A homogeneous HDL-c assay (HDL-H), which uses polyethylene glycol-modified
enzymes and sulfated alpha-cyclodextrin, was assessed for precision,
accuracy, and cholesterol and triglyceride interference. In addition, its
analytical performance was compared with that of a phosphotungstic acid
(PTA)/MgCl2 precipitation method (HDL-P). Within-run CVs were < or =
1.87%; total CVs were < or = 3.08%. Accuracy was evaluated in fresh
normotriglyceridemic sera using the Designated Comparison Method (HDL-H =
1.037 Designated Comparison Method + 4 mg/L; n = 63) and in moderately
hypertriglyceridemic sera by using the Reference Method (HDL-H = 1.068
Reference Method - 17 mg/L; n = 41). Mean biases were 4.5% and 2.2%,
respectively. In hypertriglyceridemic sera (n = 85), HDL-H concentrations
were increasingly positively biased with increasing triglyceride
concentrations. The method comparison between HDL-H and HDL-P yielded the
following equation: HDL-H = 1.037 HDL-P + 15 mg/L; n = 478. We conclude
that HDL-H amply meets the 1998 NCEP recommendations for total error; its
precision is superior compared with that of HDL-P, and its average bias
remains below +/-5% as long as triglyceride concentrations are < or = 10
g/L and in case of moderate hypercholesterolemia
Full Current Statistics in Diffusive Normal-Superconductor Structures
We study the current statistics in normal diffusive conductors in contact
with a superconductor. Using an extension of the Keldysh Green's function
method we are able to find the full distribution of charge transfers for all
temperatures and voltages. For the non-Gaussian regime, we show that the
equilibrium current fluctuations are enhanced by the presence of the
superconductor. We predict an enhancement of the nonequilibrium current noise
for temperatures below and voltages of the order of the Thouless energy
E_Th=D/L^2. Our calculation fully accounts for the proximity effect in the
normal metal and agrees with experimental data. We demonstrate that the
calculation of the full current statistics is in fact simpler than a concrete
calculation of the noise.Comment: 4 pages, 2 figures (included
Full Counting Statistics of Multiple Andreev Reflections in incoherent diffusive superconducting junctions
We present a theory for the full distribution of current fluctuations in
incoherent diffusive superconducting junctions, subjected to a voltage bias.
This theory of full counting statistics of incoherent multiple Andreev
reflections is valid for arbitrary applied voltage. We present a detailed
discussion of the properties of the first four cumulants as well as the low and
high voltage regimes of the full counting statistics. The work is an extension
of the results of Pilgram and the author, Phys. Rev. Lett. 94, 086806 (2005).Comment: Included in special issue Spin Physics of Superconducting
heterostructures of Applied Physics A: Materials Science & Processin
Assessing the potential for rainwater harvesting use in a concentrated animal feeding operation region in the south of Brazil.
Abstract: Sustainability in intensive animal production is directly linked to water management. The increasing pressure on water resources and the occurrence of increasingly frequent and severe droughts makes it harder to meet the demand for animal husbandry in rural properties and highlights the importance of rational water use and the search for alternative sources of water supply. In the midwest region of Santa Catarina state, south of Brazil, the use of cisterns to store rainwater collected from the roofs of houses that confine animals is an alternative already widely used and encouraged to minimize water scarcity. Studies that deal with the potential for rainwater use in livestock production are still scarce; however, available information provides a concrete basis for further technical and economic feasibility studies. The present study aimed to evaluate, based on local precipitation and available harvesting areas, the potential of the use of rainwater to supply the water demand (r, %) and the water-saving potential (R, m3/year) in swine and poultry Concentrated Animal Feeding Operations (CAFOs) in Jacutinga river basin and contiguous sub-basin municipalities, a region with great national importance in this activity. As a result, potential r values of 100% to supply water demand in the poultry sector and between 32.7% and 68.3% in the different production stages of the swine sector were obtained. The potential R value in the study area represented 5.2 million m3 per year. Such results reveal the high potential of rainwater harvesting systems not only for minimizing impacts of drought periods but also as an abundant source of water for supplying the husbandry water demand of rural farms, ensuring water security, and serving as a tool for managing local water resources
Current noise in long diffusive SNS junctions in the incoherent MAR regime
Spectral density of current fluctuations at zero frequency is calculated for
a long diffusive SNS junction with low-resistive interfaces. At low
temperature, T << Delta, the subgap shot noise approaches linear voltage
dependence, S=(2/ 3R)(eV + 2Delta), which is the sum of the shot noise of the
normal conductor and voltage independent excess noise. This result can also be
interpreted as the 1/3-suppressed Poisson noise for the effective charge q =
e(1+2Delta/eV) transferred by incoherent multiple Andreev reflections (MAR). At
higher temperatures, anomalies of the current noise develop at the gap
subharmonics, eV = 2Delta/n. The crossover to the hot electron regime from the
MAR regime is analyzed in the limit of small applied voltages.Comment: improved version, to be published in Phys. Rev.
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MicroRNAs Located in the Hox Gene Clusters Are Implicated in Huntington's Disease Pathogenesis
Transcriptional dysregulation has long been recognized as central to the pathogenesis of Huntington's disease (HD). MicroRNAs (miRNAs) represent a major system of post-transcriptional regulation, by either preventing translational initiation or by targeting transcripts for storage or for degradation. Using next-generation miRNA sequencing in prefrontal cortex (Brodmann Area 9) of twelve HD and nine controls, we identified five miRNAs (miR-10b-5p, miR-196a-5p, miR-196b-5p, miR-615-3p and miR-1247-5p) up-regulated in HD at genome-wide significance (FDR q-value<0.05). Three of these, miR-196a-5p, miR-196b-5p and miR-615-3p, were expressed at near zero levels in control brains. Expression was verified for all five miRNAs using reverse transcription quantitative PCR and all but miR-1247-5p were replicated in an independent sample (8HD/8C). Ectopic miR-10b-5p expression in PC12 HTT-Q73 cells increased survival by MTT assay and cell viability staining suggesting increased expression may be a protective response. All of the miRNAs but miR-1247-5p are located in intergenic regions of Hox clusters. Total mRNA sequencing in the same samples identified fifteen of 55 genes within the Hox cluster gene regions as differentially expressed in HD, and the Hox genes immediately adjacent to the four Hox cluster miRNAs as up-regulated. Pathway analysis of mRNA targets of these miRNAs implicated functions for neuronal differentiation, neurite outgrowth, cell death and survival. In regression models among the HD brains, huntingtin CAG repeat size, onset age and age at death were independently found to be inversely related to miR-10b-5p levels. CAG repeat size and onset age were independently inversely related to miR-196a-5p, onset age was inversely related to miR-196b-5p and age at death was inversely related to miR-615-3p expression. These results suggest these Hox-related miRNAs may be involved in neuroprotective response in HD. Recently, miRNAs have shown promise as biomarkers for human diseases and given their relationship to disease expression, these miRNAs are biomarker candidates in HD
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