74 research outputs found
A Detailed Analysis of One-loop Neutrino Masses from the Generic Supersymmetric Standard Model
In the generic supersymmetric standard model which had no global symmetry
enforced by hand, lepton number violation is a natural consequence.
Supersymmetry, hence, can be considered the source of experimentally demanded
beyond standard model properties for the neutrinos. With an efficient
formulation of the model, we perform a comprehensive detailed analysis of all
one-loop contributions to neutrino masses.Comment: 27 pages Revtex, no figur
Efeito da restrição alimentar qualitativa precoce sobre o desempenho, as características do trato gastrintestinal e a carcaça de frangos de corte
Effects of traffic control on the soil physical quality and the cultivation of sugarcane
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Effet de quelques traits des arbres sur la répartition des eaux de pluie en forêts tem-pérées et boréales —synthèse bibliographique
Common and rare variant association analyses in amyotrophic lateral sclerosis identify 15 risk loci with distinct genetic architectures and neuron-specific biology
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with a lifetime risk of one in 350 people and an unmet need for disease-modifying therapies. We conducted a cross-ancestry genome-wide association study (GWAS) including 29,612 patients with ALS and 122,656 controls, which identified 15 risk loci. When combined with 8,953 individuals with whole-genome sequencing (6,538 patients, 2,415 controls) and a large cortex-derived expression quantitative trait locus (eQTL) dataset (MetaBrain), analyses revealed locus-specific genetic architectures in which we prioritized genes either through rare variants, short tandem repeats or regulatory effects. ALS-associated risk loci were shared with multiple traits within the neurodegenerative spectrum but with distinct enrichment patterns across brain regions and cell types. Of the environmental and lifestyle risk factors obtained from the literature, Mendelian randomization analyses indicated a causal role for high cholesterol levels. The combination of all ALS-associated signals reveals a role for perturbations in vesicle-mediated transport and autophagy and provides evidence for cell-autonomous disease initiation in glutamatergic neurons.peer-reviewe
Laboruntersuchungen heterogener Reaktionen von Stickstoffverbindungen an Staub- und Russoberflaechen Abschlussbericht
The heterogeneous reactions of nitric acid and dinitrogen pentoxide with various authentic dust, mineral and soot surfaces has been investigated by means of the Knudsen reactor technique at room temperature. Authentic dust surfaces from the Saharan, the Chinese and the Arizona dust regions were used as substrates, as were the minerals aluminium oxide and calcite. The uptake of both trace gases was investigated at concentrations as low as 10"9 cm"-"3 (HNO_3) and 10"1"0 cm"-"3 (N_2O_5) and found to be large and irreversible. For both trace gases uptake coefficients of the order of 0.1 were determined. Water was found to have some influence onto the uptake coefficient, though this depended on the substrate used. It was observed that diffusion into the pores of the sample bulk was not relevant for the trace gases and substrates used. These results strongly suggest that mineral aerosol can redistribute nitrate from the gaseous cto the particulate phase, modifying tropospheric photochemical cycles involving NOx and NOy. (orig.)Im vorliegenden Forschungsvorhaben wurden mit Hilfe der Knudsen-Reaktor-Technik die heterogenen Reaktionen von Salpetersaeure und Distickstoffpentaoxid mit verschiedenen-authentischen Staeuben, Mineralstaeuben und Russ bei Zimmertemperatur untersucht. Als Substrate wurden authentischer Staub aus der Sahara, aus China und aus Arizona, sowie die Mineralien Aluminiumoxid und Calcit verwendet. Die Aufnahme beider Spurengase wurde bei Konzentrationen von minimal 10"9 cm"-"3 (HNO_3) und 10"1"0 cm"-"3 (N_2O_5) bestimmt. Die Aufnahme von HNO_3 und N_2O_5 war irreversibel mit Aufnahmekoeffizienten in der Groessenordnung von 0,1. Wasser hat je nach Substrat unterschiedlichen Einfluss auf die Aufnahmekoeffizienten. Diffusion von HNO_3 und N_2O_5 in die Substratporen ist nicht wichtig bei den untersuchten Substraten, so dass keine Korrektur der gemessenen Aufnahmekoeffizienten erforderlich ist. Die Ergebnisse zeigen, dass Mineralaerosol Nitrat von der Gasphase in die Partikelphase umverteilen kann, wodurch die photochemischen Kreislaeufe von NOx und NOy in der Troposphaere beeinflusst werden. (orig.)Available from TIB Hannover: F02B1588+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman
Conversion of biomass to charcoal and the carbon mass balance from a slash-and-burn experiment in a temperate deciduous forest
Anthropogenic burning, including slash-and-burn, was deliberately used in (pre)historic Central Europe. Biomass burning has affected the global carbon cycle since, presumably, the early Holocene. The understanding of processes and rates of charcoal formation in temperate deciduous forests is limited, as is the extent of prehistoric human impact on the environment. We took advantage of an experimental burning to simulate Neolithic slash-and-burn, and we quantified the biomass fuel and charcoal produced, determined the resulting distribution of the charcoal size fractions and calculated the carbon mass balance. Two-thirds of the charcoal particles (6.71 t/ha) were larger than 2000m and the spatial distribution of
charcoal was highly variable (15–90% per m2). The conversion rate of the biomass fuel to charcoal mass
was 4.8%, or 8.1% for the conversion of biomass carbon to charcoal carbon, and 58.4 t C/ha was lost during the fire, presumably as a component of aerosols or gases
Comparison among total knee arthroplasties with a mobile bearing: menisci versus rotating platform versus AP glide platform
A retrospective study was conducted on 60 patients (53 females, seven males with a mean age of 68 years and 5 months) who underwent a total knee replacement using a mobile bearing. The diagnosis was primary osteoarthritis in 57 cases and rheumatoid arthritis in three cases. None of the patients underwent a bilateral procedure, thus 60 implants (33 all cementless, three all cemented, 24 with only the tibial component cemented) were considered. Three different groups were identified: Group 1: first 20 total knee arthroplasties with menisci. Group 2: first 20 total knee arthroplasties with rotating platform. Group 3: first 20 total knee arthroplasties with AP glide platform. Clinical and radiological results at the final follow up, although different in time among the three groups, have shown no revision due to mechanical or septic reasons, and no signs of impending failure
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