Noncommutativity in quantum cosmology and the Hierarchy problem

We study the quantum cosmology of an empty (4+1)-dimensional Kaluza-Klein cosmology with a negative cosmological constant and a FRW type metric with two scale factors, one for 4-D universe and the other for one compact extra dimension. By assuming the noncommutativity in the corresponding mini-superspace we suggest a solution for the Hierarchy problem, at the level of Wheeler-DeWitt equation.Comment: 7 pages; Title, abstract and text changed; references added; to appear in PL

Modelling the distribution of Bonelli's eagle in Spain: Implications for conservation planning

Bonelli’s eagle, Hieraaetus fasciatus , has recently suffered a severe population decline and is currently endangered. Spain supports about 70% of the European population. We used stepwise logistic regression on a set of environmental, spatial and human variables to model Bonelli’s eagle distribution in the 5167 UTM 10 × 10 km quadrats of peninsular Spain. We obtained a model based on 16 variables, which allowed us to identify favourable and unfavourable areas for this species in Spain, as well as intermediate favourability areas. We assessed the stepwise progression of the model by comparing the model’s predictions in each step with those of the final model, and selected a parsimonious explanatory model based on three variables — slope, July temperature and precipitation — comprising 76% of the predictive capacity of th

Natural Hazards Challenges to Civil Engineering

info:eu-repo/semantics/publishedVersio

Selectivity of metribuzin in postemergence of culture of carrot

A citação dos autores está incorreto.The initial slow growth and short stature of carrot can allow that weeds settle in crop areas, requiring the management of these plants for productivity not to decrease. Nevertheless, weeds control has been difficult because there are few herbicides available for weeds control in postemergence of carrots. Two experiments in the field were carried out to evaluate selectivity of metribuzin applied in postemergence of carrots. A experimental randomized block design was utilized with four repetitions. Treatments consisted of metribuzin doses (0, 144, 288, 432, 576, 720, 960 and 1,200 g ha-1), applied in postemergence of carrots of the Nantes variety. Roots productivity was evaluated and percentage of commercial roots and no-commercial roots was calculated. Metribuzin has not caused visual symptoms of intoxication in carrots. Doses lower than 432 g ha-1 of metribuzin do not reduce the total productivity of roots, independent of the application period. Any doses of metribuzin changed the percentage of commercial and noncommercial roots. It is concluded that metribuzin is selective for carrots of the Nantes variety in postemergence applications at doses of 432 g ha-1.O lento crescimento inicial da cenoura favorece o estabelecimento de plantas daninhas nas áreas de cultivo, sendo necessário o manejo dessas plantas para que não ocorra redução da produtividade. Todavia, o controle tem sido dificultado por existirem poucas opções de herbicidas para o controle de plantas daninhas em pós-emergência da cultura. Dois experimentos de campo foram realizados para avaliar a seletividade do metribuzin aplicado em pós-emergência da cenoura, em dois diferentes períodos de cultivo (inverno e inverno-verão). O delineamento experimental foi o de blocos casualizados com quatro repetições. Os tratamentos corresponderam à aplicação de 0, 144, 288, 432, 576, 720, 960 e 1.200 g ha-1 do metribuzin na cultura da cenoura, cultivar Nantes. Foram avaliadas a produtividade total de raízes e a porcentagem de raízes comerciais e não comerciais. A produtividade total de raízes de cenoura não foi alterada pela aplicação de metribuzin até a dose de 432 g ha-1, independentemente da época de cultivo. A porcentagem de cenouras comercializáveis e descartáveis não foi alterada pelas doses do herbicida. Conclui-se que o metribuzin é seletivo para aplicação em pós-emergência da cenoura, cultivar Nantes, até a dose de 432 g ha-1

Optical And Physical Properties Of Er3+-yb3+ Co-doped Tellurite Fibers

In this work we present results of physical and optical properties of Er3+-Yb3+ co-doped tellurite glasses and fibers. The Double Clad Tellurite Fibers (DCTFs) are based on glasses with the composition: TeO2-WO3-Nb2O5-Na 2O-Al2O3-Er2O3-Yb 2O3. The DCTFs were fabricated by using the rod-in-tube technique and a Heathway drawing tower. The optical absorption spectra (ranging from 350 to 1750 nm) of these fibers were measured using an Optical Spectrum Analyzer (OSA). The emission spectra, around 1550 nm band, of these fibers (lengths varying from 1 to 60 cm) were obtained by using a 980nm diode laser pump. The optimal Amplified Spontaneous Emission (ASE) spectra were observed for fiber lengths ranging from 2 to 6 cm. The Er 3+/Yb3+ co-doped DCTFs show an efficient up-conversion process in comparison with the Er3+-doped DCTF. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).8120The Society of Photo-Optical Instrumentation Engineers (SPIE)Murugan, G.S., Suzuki, T., Ohishi, Y., Raman characteristics and nonlinear optical properties of tellurite and phosphotellurite glasses containing heavy metal oxides with ultrabroad Raman bands (2006) J. of Appl. Phys., 100, p. 023107Nandi, P., Jose, G., Ytterbium-doped P2O5-TeO2 glass for laser applications (2006) IEEE J. of Quat. Electron., 42, pp. 1115-1121Man, S.Q., Pun, E.Y.B., Chung, P.S., Tellurite glasses for 1.3 mm optical amplifiers" (1999) Opt. Comm., 168, pp. 369-373Wang, J.S., Vogel, E.M., Snitzer, E., Tellurite Glass: A New Candidate for Fiber Devices" (1994) Opt. Mat., 3, pp. 187-203Xu, S., Sun, H., Dai, S., Zhang, J., Jiang, Z., Upconversion luminescence of Tm3+/Yb3+-codoped oxyhalide tellurite glasses" (2005) Sol. St. Comm., 133, pp. 89-92Bookey, H.T., Lousteau, J., Jha, A., Gayraud, N., Thomson, R.R., Psaila, N.D., Li, H., Kar, A.K., Multiple rare earth emissions in a multicore tellurite fiber with a single pump wavelength" (2007) Opt. Express, 15, pp. 17554-17561Qin, G., Mori, A., Ohishi, Y., Brillouin lasing in a single-mode tellurite fiber" (2007) Opt. Lett., 32, pp. 2179-2181Zweig, A.D., Frenz, M., Romano, V., Weber, H.P., A comparative study of laser tissue interaction at 2.94 μm and 10.6 μm" (1988) Appl. Phys. B, 47, pp. 259-265Zhang, J., Dai, S., Wang, G., Sun, H., Zhang, L., Hu, L., Fabrication and emission properties of Er3+/Yb3+ codoped tellurite glass fiber for broadband optical amplification (2005) J. of Lum., 115, pp. 45-52Shixun, D., Tiefeng, X., Qiuhua, N., Xiang, S., Xunsi, W., Fabrication and gain performance of Er3+/Yb3+-codoped tellurite glass fiber (2008) J. of Rare Earths, 26, pp. 915-918Jakutis, J., Gomes, L., Amancio, C.T., Kassab, L.R.P., Martinelli, J.R., Wetter, N.U., Increased Er3+ upconversion in tellurite fibers and glasses by co-doping with Yb3+ (2010) Opt. Mat., 33, pp. 107-111Hruby, A., Evaluation of glass-forming tendency by means of DTA (1972) Czech J. Phys B, 22, pp. 1187-119

Longitudinal study in 3,000 m male runners: relationship between performance and selected physiological parameters

The purpose of the present study was to analyze longitudinal changes in 3,000 m running performance and the relationship with selected physiological parameters. Eighteen well-trained male middle-distance runners were measured six times (x3 per year) throughout two consecutive competitive seasons. The following parameters were measured on each occasion: maximal oxygen uptake (VO2max), running economy (RE), velocity at maximal oxygen uptake (vVO2max), velocity at 4mmol L-1 blood lactate concentration (V4), and performance velocity (km·h-1) in 3,000 m time trials. Values ranged from 19.59 to 20.16 km·h-1, running performance; 197 to 207 mL·kg-1·km-1. RE; 17.2 to 17.7 km·h-1, V4; 67.1 to 72.5 mL·kg-1·min-1, VO2max; and 19.8 to 20.2 km·h-1, vVO2max. A hierarchical linear model was used to quantify longitudinal relationships between running performance and selected physiological variables. Running performance decreased significantly over time, between each time point the decrease in running velocity was 0.06 km·h-1. The variables that significantly explained performance changes were V4 and vVO2max. Also, vVO2max and V4 were the measures most strongly correlated with performance and can be used to predict 3,000 m race velocity. The best prediction formula for 3,000 m running performance was: y = 0.646 + 0.626x + 0.416z (R2=0.85); where y = V3,000 m velocity (km·h-1), x = V4 (km·h-1) and z = vVO2max (km·h-1). The high predictive power of vVO2max and V4 suggest that both coaches and athletes should give attention to improving these two physiological variables, in order to improve running performance

Increasing prevalence of obesity and diabetes among patients evaluated for liver transplantation in a Swiss tertiary referral center: a 10-year retrospective analysis.

Non-alcoholic fatty liver disease (NAFLD) is now the first cause of chronic liver disease in developed countries. We aimed to assess trends in the prevalence of obesity, type 2 diabetes mellitus (T2DM) and NAFLD in patients undergoing liver transplantation evaluation and to assess whether obese patients were less likely to be listed or had an increased drop-out rate after listing. We conducted a retrospective study of all consecutive patients who underwent liver transplantation evaluation at a Swiss tertiary referral centre between January 2009 and March 2020. A total of 242 patients were included, 83% were male. The median age was 59 years (IQR, 51-64 years). The most common causes of end-stage liver disease were viral hepatitis (28%), alcoholic liver disease (21%) and NAFLD (12%). Obesity was present in 28% of our cohort, with a significant increase over time. Prevalence of type 2 diabetes mellitus followed the same trend (p = 0.02). The proportions of non-listed and listed obese patients did not differ (21% vs. 30% respectively; p = 0.3). The prevalence of obesity and type 2 diabetes mellitus significantly increased over our study period. Obese patients had similar chances of being listed. The landscape of liver transplantation indications is shifting towards NAFLD, highlighting the urgent need to prevent NAFLD progression

Nutritional Evaluation Of Children With Chronic Cholestatic Disease

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)To evaluate the nutritional status of children with persistent cholestasis and to compare the anthropometric indices between children with and without liver cirrhosis and children with and without jaundice. Methods Children with persistent cholestasis, i.e. increased direct bilirrubin or changes in the canalicular enzyme gamma-glutamyl transferase (GGT), were included. The anthropometric measures were weight (W), height or length (H), arm circumference (AC), triceps skinfold thickness (TST), arm muscle circumference (AMC), and body mass index (BMI). Results Ninety-one children with cholestasis, with current median age of 12 months, were evaluated. W/age (A) and H/A indices below -2 Z-scores were observed in 33% and 30.8% of patients, respectively. Concerning the W/H index and BMI, only 12% and 16% of patients, respectively, were below -2 Z-scores. Regarding AC, 43.8% of 89 evaluated patients had some depletion. Observing the TST, 64% of patients had depletion, and 71.1% of the 45 evaluated patients had some degree of depletion regarding the ACM index. Conclusion Evaluation using weight in patients with chronic liver diseases may overestimate the nutritional status due to visceromegaly, subclinical edema, or ascites. Indices that correlate weight and height, such as W/H and BMI, may also not show depletion because of the chronic condition in which there are depletion of both weight and height. TST, AC, and ACM are parameters that better estimate nutritional status and should be part of the management of patients with liver diseases and cholestasis. © 2015 Sociedade Brasileira de Pediatria.922197205CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq