999 resultados para 509.221


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Buccal swabs have recently been used as a minimally invasive sampling method in genetic studies of wild populations, including amphibian species. Yet it is not known to date what is the level of reliability for microsatellite genotypes obtained using such samples. Allelic dropout and false alleles may affect the genotyping derived from buccal samples. Here we quantified the success of microsatellite amplification and the rates of genotyping errors using buccal swabs in two amphibian species, the Alpine newt Triturus alpestris and the Green tree frog Hyla arborea, and we estimated two important parameters for downstream analyses, namely the number of repetitions required to achieve typing reliability and the probability of identity among genotypes. Amplification success was high, and only one locus tested required two to three repetitions to achieve reliable genotypes, showing that buccal swabbing is a very efficient approach allowing good quality DNA retrieval. This sampling method which allows avoiding the controversial toe-clipping will likely prove very useful in the context of amphibian conservation.

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Abstract: The objective of this work was to evaluate four cultivars of saccharine sorghum (Sorghum bicolor) regarding productivity, chemical composition of plant parts, and quality of the ensiling process. The tested varieties of saccharine sorghum were BRS 506, BRS 508, BRS 509, and BRS 511. The experiment was divided into two trials, which assessed: production, morphological composition, and nutritional quality of the saccharine varieties; and fermentation quality and nutritional value of the silage produced from the saccharine varieties. Of the tested varieties, BRS 509 and BRS 511 showed the highest total dry matter (DM) production. The BRS 508 variety presented the highest in vitro digestibility of the whole plant (70.65% DM). During ensiling, the BRS 509 variety showed the lowest DM loss (8.87%). The highest effluent production was observed for BRS 506 and BRS 508, with yields of 521.87 and 393.16 kg Mg-1 ensiled DM, respectively. The BRS 511 variety is the most recommended because of the best results for plant production and nutritional quality. Regarding the ensiling process, BRS 509 presents the lowest fermentation losses and the highest nutritional value of silage.

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BACKGROUND: Cardiovascular disease and non-AIDS malignancies have become major causes of death among HIV-infected individuals. The relative impact of lifestyle and HIV-related factors are debated. METHODS: We estimated associations of smoking with mortality more than 1 year after antiretroviral therapy (ART) initiation among HIV-infected individuals enrolled in European and North American cohorts. IDUs were excluded. Causes of death were assigned using standardized procedures. We used abridged life tables to estimate life expectancies. Life-years lost to HIV were estimated by comparison with the French background population. RESULTS: Among 17 995 HIV-infected individuals followed for 79 760 person-years, the proportion of smokers was 60%. The mortality rate ratio (MRR) comparing smokers with nonsmokers was 1.94 [95% confidence interval (95% CI) 1.56-2.41]. The MRRs comparing current and previous smokers with never smokers were 1.70 (95% CI 1.23-2.34) and 0.92 (95% CI 0.64-1.34), respectively. Smokers had substantially higher mortality from cardiovascular disease, non-AIDS malignancies than nonsmokers [MRR 6.28 (95% CI 2.19-18.0) and 2.67 (95% CI 1.60-4.46), respectively]. Among 35-year-old HIV-infected men, the loss of life-years associated with smoking and HIV was 7.9 (95% CI 7.1-8.7) and 5.9 (95% CI 4.9-6.9), respectively. The life expectancy of virally suppressed, never-smokers was 43.5 years (95% CI 41.7-45.3), compared with 44.4 years among 35-year-old men in the background population. Excess MRRs/1000 person-years associated with smoking increased from 0.6 (95% CI -1.3 to 2.6) at age 35 to 43.6 (95% CI 37.9-49.3) at age at least 65 years. CONCLUSION: Well treated HIV-infected individuals may lose more life years through smoking than through HIV. Excess mortality associated with smoking increases markedly with age. Therefore, increases in smoking-related mortality can be expected as the treated HIV-infected population ages. Interventions for smoking cessation should be prioritized.

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The effect of age at the first mating and herd size were evaluated in the reference Spanish Databank (BDporc) of 37 698 sows born between 1991 and 1995 and with individual lifetime records. The data included dates of births at entrance and culling, first mating, repetitive mating and conception, first farrowing and weaning records. Individual records were validated before the analysis by screening them through a tolerance “filter” in order to eliminate the extreme values from the analysis. The total database of the sows was classified in 7 classes according to age at the first mating (< 210, 210–220, 221–230, 231–240, 241–250, 251–270, and > 270 days) and in 6 classes of herd size (< 200, 200–300, 301–400, 401–600, 601–800, and > 800 sows). The total number of litters and number of weaned piglets obtained from each sow during the lifetime production were significantly (P < 0.05) greater for gilts between 221 and 240 d of age at the first mating. There was a significant (P < 0.001) effect of the herd size on the reproductive performance of the sow, and the best performance was obtained with herds with 401 to 600 sows compared to < 200 or > 800 sow-herds. Furthermore, a significant (P < 0.001) interaction between age at the first mating and herd size was detected and can be associated with a particular pattern for the herd size class 401–600 sows with the best performances obtained for the sows first mated at less than 200 days. For the other herd sizes, the results indicated that sows mated for the first time at the right age, 221–240 days, are more productive, both in the number and size of the parities throughout lifetime production.

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Collection : Les études de la Documentation française

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Se llevó a cabo un experimento de 406 días en macetas para evaluar el nuevo inhibidor de la nitrificación, 3,4-dimetilpirazol fosfato (DMPP), añadido a purines de cerdo. Se utilizaron macetas que contenían tierra franca calcárea que fueron sujetas a los siguientes tratamientos: sin purín, 73,7; 147,3 y 221 cm3 de purín por maceta, todas con o sin tratamiento de DMPP. A los 18 días las macetas fueron sembradas con Lolium perenne L. El mayor rendimiento (36,3 g maceta-1) se obtuvo para el tratamiento con la dosis superior de purín y DMPP, siendo un 7,4% superior al mismo tratamiento sin inhibidor y un 46,1% superior al tratamiento control. Las plantas tratadas con dosis alta y mediana, más el DMPP, absorbieron el 70% del total del N durante la primera fase del experimento (104 días) mientras que sin inhibidor absorbieron el 55,3 y el 62% respectivamente. Se observó una reducción significativa del 17% en el N lixiviado en los tratamientos sin cultivo al aplicar DMPP. El inhibidor aumentó significativamente la eficiencia agronómica del purín (g materia seca g-1 N aplicado).

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Cuando una empresa se decide a realizar una iniciativa comercial en Internet, al igual que en el mundo físico, es necesario definir un diseño adecuado del sitio web que se ajuste a su idea de negocio y a su público objetivo. El presente trabajo trata de analizar como influye el diseño del establecimiento virtual en el desarrollo de la gestión comercial, incidiendo en los siguientes aspectos: diseño gráfico, usabilidad y accesibilidad. A partir de este análisis, se estudian los distintos grupos de consumidores con comportamientos homogéneos y se posicionan en función de sus actitudes. El análisis también permite definir la calidad del servicio prestado por este tipo de establecimientos, así como las principales dimensiones en que se despliega. En las conclusiones se citan aspectos en los que el gestor de una tienda online debe incidir para mejorar la calidad de su servicio.

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Este artículo se basa en parte de los resultados de la investigación del autor sobre la identificación de los factores motivacionales que subyacen en las decisiones que toman los profesores sobre su participación en actividades de formación permanente. Se concluyó que, si bien los profesores deciden participar en estas actividades principalmente por la presencia de ciertos factores motivadores o intrínsecos que afectan a su instrumentalidad percibida, sus decisiones de no participar se basan principalmente en la ausencia de otros factores extrínsecos que afectan a la expectativa de realización de las actividades.

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Se presenta una síntesis de los resultados obtenidos en los estudios de semillas y frutos realizados durante los últimos años en la Cataluña Occidental (especialmente en el llamado Llano Occidental Catalán) en yacimientos del II y I milenio a.n.e. Entre las plantas cultivadas destacan claramente los cereales, sobre todo la cebada vestida (Hordeum vulgare) y el trigo común/duro (Triticum aestivum/durum), con escasa presencia de leguminosas, siendo las más representadas la lenteja (Lens culinaris) y el guisante (Pisum sativum). Nuevos cultivos como los mijos (Panicum miliaceum y Setaria italica) o el lino (Linum usitatissimum) se detectan ya desde mediados del II milenio, mientras que otros como la avena (Avena sativa) se introducen en época ibérica. Se han recuperado también testimonios de recolección, como las bellotas (Quercus sp.) o la uva silvestre (Vitis vinifera ssp. sylvestris), así como de la vegetación arvense, principalmente el raygrás (Lolium sp.).

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Es va avaluar el contingut del sòl en Mn, Cu, Zn, Ni i Cd fent una extracció amb DTPA, segons el mètode de Lindsay i Norvell (1969). Les mostres analitzades procedien de parcel·les agrícoles d'arreu de Catalunya, conservades al Banc de Mostres de Sòls del Mapa de Sòls de Catalunya del DARP. Els resultats es van agrupar per sistemes agrícoles en funció de l'origen de les mostres, ja que dins de cada un es pot assumir una reducció important en l'interval de variació de diferents factors. Es va realitzar una comparació estadística entre els valors mitjans dels diferents sistemes agrícoles, entre els valors mitjans de les dues profunditats de sòl considerades, i una interpretació agronòmica. Els resultats van indicar que els sòls procedents d'horticultura intensiva del Maresme són els que tenen continguts disponibles més elevats dels metalls considerats. D'altra banda, es fa palès que els valors estan condicionats tant pel material originari del sòl com per l'acció antròpica. Per al Cu i el Zn en les mostres de sòls del Maresme els continguts trobats estan molt per sobre dels mínims considerats com a agronòmicament satisfactoris.

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Background: Proliferative retinopathy is an important cause of vision loss in diabetic patients. Incomplete panretinal photocoagulation (PRP) can lead to recurrent proliferation of new vessels. Patients and Methods: We retrospectively analysed the outcome of patients with high risk proliferative diabetic retinopathy (PDR) previously treated with slit lamp PRP who underwent indirect fill in argon laser treatment with scleral indentation under anesthesia for persistent neovascular proliferation. Results: Seventeen eyes of ten patients were included. The mean age at diabetes onset was 17.3 years SD 16.2 (range 2-44). All patients reported long standing poor glycemic control (mean HbA1c: 8.5 % SD 1.3 range 5.9-10.2). The area of retinal ischemia decreased significantly from 15 ± 7.5 disk areas (DA) before fill-in laser to 3.2 ± 4.2 DA after fill-in laser (p = 0.001). The new vessels also regressed significantly after laser treatment 8.6 ± 6.1 DA before treatment versus 6.5 ± 6.4 DA after laser treatment, (p = 0.044). Quiescent PDR was reached in 10 eyes (58.8 %) at the last visit. Conclusions: Fill-in indirect argon laser under general anesthesia should be considered to achieve further new vessels regression in high risk PDR patients. Scleral indentation and absence of pain may allow for more extensive laser application.