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ABSTRACT This paper reports the experiences of making Portland cement based corrugated roof sheets with the reinforcement of a Colombian natural fiber, named fique. The sheets were manufactured by a [...]

The structural and optical properties of gold-nucleated GaN grown on Au/Si (100) and Au/c-sapphire were enhanced using a post-annealing procedure at 950 °C, under an ammonia environment. Before the GaN chemical vapor deposition process, the formation of Au droplets was promoted by an in situ dewetting mechanism, applying a heat treatment to the Au-covered c-sapphire, and silicon (100) substrates. The size and morphology of the Au sites were characterized by atomic force microscopy. According to the X-ray diffraction and Raman spectroscopy results, crystalline enhancement of the GaN wurtzite structure was obtained in both, the Au/sapphire and Au/Si (100). SEM micrographs reveal the presence of GaN micro-whiskers in as-grown samples. After the treatment herein proposed, morphology was modified as shown in the plan-view and cross section results. The GaN near-band emission at 3.34 eV was boosted by the localized surface plasmon effect. Additionally, the GaN bandgap energy was estimated by diffuse reflectance measurements and by the modified Kubelka–Munk function, as 3.35 eV.

Purpose: The effect of the sodium-glucose 2 (SGLT-2) inhibitors on microvascular complications remains uncertain. We performed a systematic review to determine the efficacy of the SGLT-2 inhibitors on microvascular outcomes in patients with type 2 diabetes. Methods: A comprehensive search was performed using Ovid, MEDLINE, EMBASE, Web of Science, and Scopus from inception to May 2019. Randomized trials comparing SGLT-2 inhibitors with placebo or other medication for type 2 diabetes for ≥ 4 weeks were included. Diabetes-related microvascular complications such as nephropathy, retinopathy, neuropathy, and peripheral vascular disease were evaluated. A random-effect model using mean differences for continuous outcomes and risk ratio for dichotomous outcomes was used to synthesize data. PROSPERO (CRD 42017076460). Results: A total of 40 RCTs with overall moderate quality of evidence were included. SGLT-2 inhibitors reduced the risk of renal-replacement therapy (0.65; 95% CI 0.54–0.79), renal death (0.57; 95% CI 0.49–0.65), and progression of albuminuria (0.69; 95% CI 0.66–0.73). Conversely, they appeared ineffective in maintaining eGFR (0.33; 95% CI − 0.74 to 1.41) or reducing serum creatinine (− 0.07; 95% CI − 0.26 to 0.11), whereas urine albumin–creatinine ratio (− 23.4; 95% CI − 44.6 to − 2.2) was reduced. Risk of amputation was non-significant (1.30; 95% CI 0.93–1.83). No available data were found regarding neuropathy and retinopathy to perform a quantitative analysis. Conclusion: SGLT-2 inhibitors may reduce the risk of renal patient-important outcomes but fail to improve surrogate outcomes. Apparently, no increased risk of amputations was observed with these medications. No data were available regarding other microvascular complications.

Tumor necrosis factor-α (TNF-α)-induced RIP1/RIP3 (receptor-interacting protein kinase 1/receptor-interacting protein kinase 3)-mediated necroptosis has been proposed as an alternative strategy for treating apoptosis-resistant leukemia. However, we found that most acute myeloid leukemia (AML) cells, especially M4 and M5 subtypes, produce TNF and show basal level activation of RIP1/RIP3/MLKL signaling, yet do not undergo necroptosis. TNF, through RIP1/RIP3 signaling, prevents degradation of SOCS1, a key negative regulator of interferon-γ (IFN-γ) signaling. Using both pharmacologic and genetic assays, we show here that inactivation of RIP1/RIP3 resulted in reduction of SOCS1 protein levels and partial differentiation of AML cells. AML cells with inactivated RIP1/RIP3 signaling show increased sensitivity to IFN-γ-induced differentiation. RIP1/RIP3 inactivation combined with IFN-γ treatment significantly attenuated the clonogenic capacity of both primary AML cells and AML cell lines. This combination treatment also compromised the leukemogenic ability of murine AML cells in vivo. Our studies suggest that inhibition of RIP1/RIP3-mediated necroptotic signaling might be a novel strategy for the treatment of AML when combined with other differentiation inducers.

We hypothesized that preemptive fibrinogen administration to obtain an initial plasma level of 2.9 g/L would reduce transfusion requirements in liver transplantation. A randomized, multicenter, hemoglobin‐stratified, double‐blind, fibrinogen‐versus‐saline–controlled trial was conducted. The primary end point was the percentage of patients requiring red blood cells. We evaluated 51 patients allocated to fibrinogen and 48 allocated to saline; the primary end point was assessed using data for 92 patients because the electronic record forms were offline for three patients in the fibrinogen group and four in the saline group. We injected a median of 3.54 g fibrinogen preemptively in the fibrinogen group. Nine patients in the saline group (20.9%) required fibrinogen at graft reperfusion (compared with one patient [2.1%] in the fibrinogen group; p = 0.005). Blood was transfused to 52.9% (95% confidence interval [CI]42.5–63.3%) in the fibrinogen group and 42.74% (95% CI28.3–57.2%) in the saline group (p = 0.217). Relative risk for blood transfusion was 0.80 (95% CI0.57–1.13). Thrombotic events occurred in one patient (2.1%) and five patients (11.4%) in the fibrinogen and saline groups, respectively. Seven patients (14.6%) in the fibrinogen group and nine (20.3%) in the saline group required reoperation. Preemptive administration of fibrinogen concentrate did not influence transfusion requirements. In this prospective, randomized, multicenter, double‐blind study, the investigators confirm the marked loss of plasma fibrinogen during liver transplantation and the need for intraoperative fibrinogen replacement.

This study is devoted to a consistent derivation of an effective model Hamiltonian to describe spin transport along a helical pathway and in the presence of spin–orbit interaction, the latter being induced by an external field with helical symmetry. It is found that a sizable spin polarization of an unpolarized incoming state can be obtained without introducing phase breaking processes. For this, at least two energy levels per lattice site in the tight-binding representation are needed. Additionally, asymmetries in the effective electronic-coupling parameters as well as in the spin–orbit interaction strength must be present to achieve net polarization. For a fully symmetric systemin terms of electronic and spin–orbit couplingsno spin polarization is found. The model presented is quite general and is expected to be of interest for the treatment of spin-dependent effects in molecular scale systems with helical symmetry.

Objective: Endophytes, microorganisms that reside in the tissues of living plants, are a promising source of novel compounds with biological activity, or an alternative source of compounds originally isolated from higher plants. The intent of this review is to provide insights into their occurrence in nature, the products that they make, and how some of these organisms are beginning to show some potential for human use. Methods: Information for analysis of endophytic microorganisms was obtained from libraries and Internet scientific databases such as Scirus, Google Scholar, CAB-Abstracts, MedlinePlus, PubMed, SciFinder, Scopus and Web of Science. Results: Many of the compounds reported here were isolated exclusively from endophytes in culture, while other compounds had been previously reported as chemical constituents of higher plants. A survey of the literature shows endophytic microorganisms are mainly known for their alkaloids with cytotoxic, chemopreventive, anti-metastatic and antitumor properties used in the treatment of several types of cancer. The studies of these alkaloids highlight the existence of various potential leads for the development of novel anti-cancer agents. Modern pharmacology studies demonstrated that their crude extracts and active compounds possess wide pharmacological actions, especially for anti-microbial drug discovery, with neuroprotective, antioxidant, nematicidal, antiplasmodium, anti-inflammatory activities. Aim of the Review: This review summarizes the up-to-date and comprehensive information on compounds from endophytes fungi from 1995 to 2011 that relates to 313 compounds isolated from endophytic microorganisms, together with the botany, phytochemistry, pharmacology and toxicology, and discusses possible trends and the scope for future research of endophytes.

Abstract: Viral hepatitis A and B are known to cause acute liver failure. While nearly 20% of acute liver failure cases are of indeterminate etiology, screening for other viruses has not been uniformly performed. We looked for evidence for parvovirus B19 and hepatitis E virus in sera from U.S. acute liver failure patients. For B19, 78 patients’ sera, including 34 with indeterminate etiology, were evaluated by DNA dot-blot hybridization, reverse transcription polymerase chain reaction, and enzyme-linked immunosorbent assay for immunoglobin G and M antibodies; none showed evidence for infection. In like manner, 126 patients’ sera were analyzed for hepatitis E virus RNA by reverse transcription polymerase chain reaction and for hepatitis E virus immunoglobin G and M antibodies by enzyme-linked immunosorbent assay; no acute hepatitis E virus cases were identified. If a unique acute liver failure virus exists, it is neither of these candidate agents.

We analyzed demographic data from northern spotted owls (Strix occidentalis caurina) from 14 study areas in Washington, Oregon, and California for 1985–2003. The purpose of our analyses was to provide an assessment of the status and trends of northern spotted owl populations throughout most of their geographic range. The 14 study areas made up approximately 12% of the range of the subspecies and included federal, tribal, private, and mixed federal and private lands. The study areas also included all the major forest types that the subspecies inhabits. The analyses followed rigorous protocols that were developed a priori and were the result of extensive discussions and consensus among the authors. Our primary objectives were to estimate fecundity, apparent survival (ϕ), and annual rate of population change (λ) and to determine if there were any temporal trends in these population parameters. In addition to analyses of data from individual study areas, we conducted 2 meta‐analyses on each demographic parameter. One meta‐analysis was conducted on all 14 areas, and the other was restricted to the 8 areas that constituted the Effectiveness Monitoring Plan for northern spotted owls under the Northwest Forest Plan. The average number of years of reproductive data per study area was 14 (range = 5–19), and the average number of recapture occasions per study area was 13 (range = 4–18). Only 1 study area had <12 years of data. Our results were based on 32,054 captures and resightings of 11,432 banded individuals for estimation of survival and 10,902 instances in which we documented the number of young produced by territorial females. The number of young fledged (NYF) per territorial female was analyzed by testing a suite of a priori models that included (1) effects of age, (2) linear or quadratic time trends, (3) presence of barred owls (Strix varia) in spotted owl territories, and (4) an even‐odd year effect. The NYF varied among years on most study areas with a biennial cycle of high reproduction in even‐numbered years and low reproduction in odd‐numbered years. These cyclic fluctuations did not occur on all study areas, and the even‐odd year effect waned during the last 5 years of the study. Fecundity was highest for adults (x̄=0.372, SE = 0.029), lower for 2‐year‐olds (x̄= 0.208, SE = 0.032), and very low for 1‐year‐olds (x̄= 0.074, SE = 0.029). Fecundity was stable over time for 6 areas (Rainier, Olympic, Warm Springs, H. J. Andrews, Klamath, and Marin), declining for 6 areas (Wenatchee, Cle Elum, Oregon Coast Range, Southern Oregon Cascades, Northwest California, and Simpson), and slightly increasing for 2 areas (Tyee, Hoopa). We found little association between NYF and the proportion of northern spotted owl territories where barred owls were detected, although results were suggestive of a negative effect of barred owls on the Wenatchee and Olympic study areas. The meta‐analysis on fecundity indicated substantial annual variability with no increasing or decreasing trends. Fecundity was highest in the mixed‐conifer region of eastern Washington (x̄= 0.560, SE = 0.041) and lowest in the Douglas‐fir (Pseudotsuga menziesii) region of the Oregon coast (x̄= 0.306, SE = 0.039). We used Cormack‐Jolly–Seber open population models and Program MARK to estimate apparent survival rates of owls >1 year old. We found no differences in apparent survival rates between sexes except for 1 area (Marin), which had only 6 years of data. Estimates of apparent survival from individual study areas indicated that there were differences among age classes with adults generally having higher survival than 1‐ and 2‐year‐olds. Apparent survival rates ranged from 0.750 (SE = 0.026) to 0.886 (SE = 0.010) for adults, 0.626 (SE = 0.073) to 0.886 (SE = 0.010) for 2‐year‐olds, and 0.415 (SE = 0.111) to 0.860 (SE = 0.017) for 1‐year‐olds. These estimates were comparable to survival rates from previous studies on the subspecies. We found evidence for negative time trends in survival rates on 5 study areas (Wenatchee, Cle Elum, Rainier, Olympic, and Northwest California) and no trends in survival on the remaining areas. There was evidence for negative effects of barred owls on apparent survival on 3 study areas (Wenatchee, Cle Elum, and Olympic). Survival rates of adult owls on the 8 Monitoring Areas generally were high, ranging from 0.85 (SE = 0.009) to 0.89 (SE = 0.010), but were declining on the Cle Elum, Olympic, and Northwestern California study areas. The meta‐analysis of apparent survival indicated differences among regions and changes over time with a downward trend in the mixed‐conifer and Douglas‐fir regions of Washington. The meta‐analysis of apparent survival also indicated that there was a negative association between fecundity and survival the following year, suggesting a cost of reproduction on survival. This effect was limited to the Douglas‐fir and mixed‐conifer regions of Washington and the Douglas‐fir region of the Oregon Cascade Mountains. We used the reparameterized Jolly‐Seber method (λRJS) to estimate annual rate of population change of territorial owls in the study areas. This estimate answers the question, Are these territorial owls being replaced in this geographically open population? Point estimates of λRJSwere <1.0 for 12 of 13 study areas. The analyses provided strong evidence that populations on the Wenatchee, Cle Elum, Rainier, Olympic, Warm Springs, H. J. Andrews, Oregon Coast Ranges, and Simpson study areas were declining during the study. The mean λRJSfor the 13 study areas was 0.963 (SE = 0.009), suggesting that populations over all the areas were declining about 3.7% per year during the study. The mean λRJSfor the 8 monitoring areas for the Northwest Forest Plan was 0.976 (SE = 0.007) compared to a mean of 0.942 (SE = 0.016) for the other study areas, a 2.4‐versus‐5.8% decline per year. This suggested that owl populations on federal lands had higher demographic rates than elsewhere; thus, the Northwest Forest Plan appeared to have a positive effect on demography of northern spotted owls. Populations were doing poorest in Washington, where apparent survival rates and populations were declining on all 4 study areas. Our estimates of λRJSwere generally lower than those reported in a previous analysis (λRJS= 0.997, SE = 0.003) for many of the same areas at an earlier date. The possible causes of population declines include but are not limited to habitat loss from timber harvest and fires, competition with barred owls, and weather patterns. Analizamos datos demográficos de búhos moteados norteños (Strix occidentalis caurina) de catorce áreas de estudio en los estados de Washington, Oregón y California durante el periodo 1985–2003. El propósito de nuestro análisis fue generar una evaluación del estado y de las tendencias de las poblaciones de búhos a través de la mayor parte de su extensión geográfica. Las catorce áreas de estudio comprendían aproximadamente el doce por ciento de la extensión de esta subespecie y comprendían tierras federales, tribales, privadas y una mezcla de tierras federales y privadas. Las áreas de estudio también incluian los principales tipos de bosques que habita la subespecie. Los análisis seguian protocolos rigurosos que fueron desarrollados a priori y fueron el resultado de discusiones prolongadas y el consenso de los autores. Nuestros objetivos principales eran: estimar la fecundidad, supervivencia aparente (ϕ) y tasa anual de cambio de población (λ) para determinar si había algunas tendencias temporales dentro de estos parámetras de población. Además de los análisis de los datos de las áreas de estudio individuales, realizamos dos meta‐análisis en cada parámetra demográfico. Un meta‐análisis se realizó en las catorce áreas y el otro se restringió a las ocho áreas que constituían el Effectiveness Monitoring Plan (Plan Monitor de Eficacia) para Strix occidentalis caurinabajo el Northwest Forest Plan (Plan Forestal del Noroeste). El promedio de número de años de datos de reproducción por área de estudio era catorce (rango = 5–19), y el promedio de número de ocasiones de recaptura por área de estudio era 13 (rango = 4–18). Sólo un área de estudio tenia < 12 años de datos. Nuestros resultados se basaron en 32.054 capturas y revistas de los 11.432 individuos anillados para la estimación de supervivencia, y 10.902 ocasiones en que documentamos el número de crias producidas por hembras territoriales. El número de pájaros volantones (NPV = número de volantones que había abandonado el nido) por hembra territorial se analizó comprobando un grupo de modelos a priori que incluían: (1) los efectos de la edad, (2) tendencias cronológicas lineales o cuadráticas, (3) la presencia de Strix variaen territorios de Strix occidentalis caurina, (4) el efecto año par/impar. Estas fluctuaciones cíclicas no ocurrieron en todas las áreas de estudio, y el efecto año par/impar disminuía durante los últimos cinco años del estudio. La fecundidad era más alta para adultos (media = 0.372, error standar [ES] = 0.029), más baja para individuos de dos años (media = 0.208, ES = 0.032), y muy baja para individuos de un año (media = 0.074, ES = 0.029). Es más, encontramos que la fecundidad era estable durante el periodo del estudio en 6 áreas de estudio (Rainier, Olympic, Warm Springs, H. J. Andres, Klamath y Marin), posiblemente declinante para 6 áreas (Wenatchee, Cle Elum, Oregon Coast Range, Southern Oregon Cascades, Northwest California y Simpson), y ligeramente incremente para dos áreas. Encontramos poca relación entre NPV y la proporción de territorios de Strix occidentalis caurinadonde se detectaba la presencia de Strix varia, si bien los resultados sugieren un efecto negativo de Strix variaen las áreas de Wenatchee y Olympic. El meta‐análisis de fecundidad indicó bastante variabilidad anual sin ninguna tendencia creciente ni decreciente. La fecundidad era más alta en la región de coníferas mixtas de Washington oriental (media = 0.560, ES = 0.041) y más baja en la región de abeto Douglas (Pseudotsuga menziesii) en la región de Oregón litoral (media = 0.306, ES = 0.039). Usamos modelos de población Cormack‐Jolly‐Sebery el Program MARK para estimar tasas de supervivencia aparente de búhos de >1 año. No encontramos ninguna diferencia en tasas de supervivencia aparente entre sexos, excepta para un área de estudio (Marin), que sólo tenía seis años de datos. Las estimaciones de supervivencia aparente de las áreas de estudios individuales indican que había diferencias entre grupos de edad y, en general, los adultos tenían una tasa de supervivencia más alta que los búhos de un y dos años. Las tasas de supervivencia aparente para búhos adultos varían de 0.750 (ES = 0.026) a 0.886 (ES = 0.010) y concordaban con las estimaciones de estudios previos acerca de la subespecie. Las tasas de supervivencia aparente para búhos de dos años varian de 0.626 (ES = 0.073) a 0.866 (ES = 0.010), y las de búhos de un año varían de 0.415 (ES = 0.111) a 0.860 (ES = 0.017). Encontramos muestras de tendencias cronológicas negativas en las tasas de supervivencia en cinco áreas de estudio (Wenatchee, Cle Elum, Rainier, Olympic y Northwest California) y ninguna tendencia en supervivencia en las demás áreas. Habia muestras de efectos negativos de Strix variaen la supervivencia aparente en tres àreas de estudio (Wenatchee, Cle Elum y Olympic). Las tasas de supervivencia de búhos en las ocho Monitoring Areas (Areas de Control) eran generalmente altas, variando de 0.85 (ES = 0.009) a 0.89 (ES = 0.010); pero eran decrecientes en las áreas de estudio Cle Elum, Olympic y Northwest California. El meta‐análisis de supervivencia aparente indica diferencias entre regiones y cambios con el paso del tiempo con una tendencia declinante en las regiones de coniferas mixtas y de abeto Douglas (Pseudotsuga menziesii) en Washington. El meta‐análisis de supervivencia aparente también indica que había una asociación negativa entre la fecundidad y la supervivencia para el año siguiente, lo que sugiere que la reproducción tenía un efecto perjudicial en la supervivencia al año siguiente. Este efecto se limitó a las regiones de Washington y la región de abeto Douglas (Pseudotsuga meniesii) en las Montañas Cascadas de Oregón. Usamos el método Jolly‐Seber modificado (λRJS) que determina el estado de la población de búhos territoriales en las áreas de estudio. Contesta la pregunta, ?Estos búhos territoriales están siendo reemplazados en esta población geográfica abierta? Estimaciones de puntos (λRJS) eran de <1.0 de doce de los trece áreas de estudio. Los análisis dieron indicios fuertes que las poblaciones en las areas de estudio en Wenatchee, Cle Elum, Rainier, Olympic, Warm Springs, H. J. Andrews, Oregon Coast Ranges y Simpson disminuían durante el estudio. La media λRJSpara las trece áreas de estudio era 0.963 (ES = 0.009), lo que sugiere que las poblaciones en todas las otras áreas de estudio disminuían aproximadamente en un 3,7% por año durante el estudio. La media λRJSpara las ocho áreas de control del Plan Forestal del Noroeste era 0.976 (ES = 0.009) comparada con una media de 0.942 (ES = 0.016) para las otras áreas de estudio, una disminución de 2,4 versus 5,8% por año. Esto sugiere que las poblaciones de búhos en las tierras federates tenían tasas demográficas más altas que en otras áreas; por tanto, el Plan Forestal del Noroeste parece haber tenido un efecto positivo en la demografía de Strix occidentalis caurina. Las poblaciones que no prosperaban se encontraban en Washington, donde las tasas de supervivencia aparente y las poblaciones disminuian en todas (4) las áreas de estudio. Nuestras estimaciones de λRJSeran generalmente más bajas que las indicadas en un análisis previo (λRJS= 0.997, ES = 0.003) para muchas de las mismas áreas en fechas anteriores. Las causas posibles de estas disminuciones en población incluyen, pero no se limitan a: pérdida de hábitat debido a talas forestales e incendios forestales, competencia con Strix variay ciclos climatológicos. Le Statut et les Tendances dans la Démographie des Chouettes Tachetées Septentrionales, 1985–2003 Nous avons analysé des données démographiques des chouettes tachetées septentrionales (Strix occidentalis caurina) de 14 secteurs d'étude dans Washington, Oregon, et Californie pour la période de 1985–2003. Le but de notre analyse était de fournir une évaluation du statut et les tendances de la population des chouettes tachetées septentrionales à travers la plupart de leur gamme géographique. Les 14 secteurs d'étude ont compris approximativement 12% d'une variété de sous‐espèces en incluant les terres fédérales, tribales, privées et un mélange de terres fédérales et privées. Les secteurs d'étude ont inclus aussi tous les types de forêts majeurs où les sous‐espèces habitent. Les analyses ont suivi des protocoles rigoureux qui ont été développés a priori et étaient le résultat de discussions extensives et d'accords parmi les auteurs. Notre objectif primaire était d'estimer la fécondité, la survie apparente (ϕ), et le taux annuel de changement de population (λ) et déterminer s'il y avait des tendances temporelles dans ces paramètres de population. En assemblant les analyses de données des secteurs d'étude individuels, nous avons dirigé 2 méta analyses sur chaque paramètre démographique. Une méta analyse a été dirigée sur tous les 14 secteurs et l'autre a été limitée aux 8 secteurs qui ont constitué le plan de contrôle d'efficacité pour les chouettes tachetées septentrionales sous le Projet de Forêt Nord‐ouest. Le nombre moyen d'années de données reproductives par les secteurs d'étude était de 14 (variation = 5–19), et le nombre moyen des occasions de recapture par le secteur d'étude était de 13 (variation = 4–18). Seulement 1 secteur d'étude avait moins de 12 années de données. Nos résultats ont été basés sur 32,054 captures et des portées de vue de 11,432 individus bandés pour l'estimation de survie, et 10,902 cas pour lesquels nous avons documenté le nombre de jeunes produits par les femelles territoriales. Le nombre de petit d'hiboux (NYF) par femelle territoriale a été analysé en essayant des modèles a priori qui ont inclus: (1) les effets de l'âge, (2) les tendances de temps linéaires ou quadratiques, (3) les effets de chouettes striées (Strix varia), et (4) un effet d'année pair‐impair. NYF a varié parmi les années pour la plupart des secteurs d'étude avec un cycle biennal de haute reproduction des années numérotées paires et de basse reproduction des années numérotées impaires. Ces variations cycliques n'ont pas eu d'effet sur tous les secteurs d'étude, et l'effet de l'année pair‐impair a diminué pendant les 5 dernières années de l'étude. La fécondité était plus élevée pour les adultes (moyenne = 0,372, standard error [SE] = 0,029), moins élevée pour ceux âgés de 2 ans (moyenne = 0,208, SE = 0,032), et très basse pour ceux âgés d'un an (les moyennes = 0,074, SE = 0,029). De plus, nous avons trouvé que cette fécondité était stable progressivement pour 6 secteurs d'étude (Rainier, Olympic, Warm Springs, H. J. Andrews, Klamath, et Marin), en déclin probablement pour 6 secteurs (Wenatchee, Cle Elum, les chaînes de la côte d'Oregon, les chaînes méridionales d'Oregon, le Nord‐ouest de la Californie, et Simpson), et en légère augmentation 2 secteurs (Tyee, Hoopa). Nous avons trouvé peu d'association entre NYF et la proportion de territoires des chouettes tachetées où les chouettes striées ont été détectées, bien que les résultats étaient suggestifs d'un effet négatif des chouettes striées pour le Wenatchee et les secteurs d'étude de l'Olympic. La méta analyse sur la fécondité a indiqué la variabilité annuelle substantielle sur les tendances avec ou sans croissance. La fécondité était plus élevée dans la région mixte de conifère de l'est de Washington (moyenne = 0,560, SE = 0,041) et moins élevée dans la région des Sapins de Douglas (Pseudotsuga menziesii) de la Côte d'Oregon (moyenne = 0,306, SE = 0,039). Nous avons utilisé les modèles ((Cormack‐Jolly‐Seber open population)) et le Programme MARK et la statistique d'information théorique pour estimer les taux de survie apparents des chouettes âgés d'un an et plus. Nous n'avons pas trouvé de différences dans les taux de survie apparents entre les sexes à l'exception d'un secteur d'étude (Marin) qui avait seulement 6 années de données. Les estimations de survie apparente des secteurs d'étude individuels ont indiqué qu'il y avait des différences parmi les classes d'âge avec les adultes généralement ayant la plus haute survie que ceux âgés de 1 et 2 ans. Les évaluations de survie apparentes pour les vielles chouettes adultes variaient de 0,750 (SE = 0,026) à 0,886 (SE = 0,010) et étaient comparable aux estimations des études précédentes de la sous‐espèce. Les taux apparents de survie de ceux âgés 2 ans variaient de 0,626 (SE = 0,073) à 0,886 (SE = 0,010), et ceux âgés de 1 an variaient de 0,415 (SE = 0,111) à 0,860 (SE = 0,017). Nous avons trouvé une évidence de tendance de temps négatif en taux de survie sur 5 secteurs d'étude (Wenatchee, Cle Elum, Rainier, Olympic et Nord‐ouest de la Californie) et aucunes tendances de survie pour les secteurs restants. Il y avait des preuves d'effets négatifs sur le taux apparent de survie des chouettes striées dans 3 secteurs d'étude (Wenatchee, Cle Elum et Olympic). Les taux de survie des chouettes sur les 8 Secteurs de Surveillance étaient généralement élevés, s'étendant de 0,85 à 0,89; mais étaient en déclin sur les secteurs d'étude de Cle Elum, Olympic et le Nord‐ouest de la Californie/La méta analyse de survie apparente a indiqué qu'il y avait des différences parmi les régions et des changements progressifs avec une tendance décroissante dans les régions mixtes de conifère et des Sapins de Douglas de l'état de Washington. La méta analyse de survie apparente a indiqué aussi qu'il y avait une association négative entre la fécondité et la survie pour l'année suivante. Cet effet a été limité aux régions des Sapin de Douglas, aux régions mixtes de conifère de Washington et de la région de Sapin de Douglas dans les chaînes de montagnes d'Oregon. Nous avons utilisé une méthode modifiée de Jolly‐Seber (λRJS) qui détermine le statut de la population des chouettes territoriales dans les secteurs d'étude. Cela répond à la question, ces chouettes territoriales sont‐elles remplacées géographiquement dans cette ouverture de la population? Les points d'estimations de λRJSétaient <1.0 pour 12 des 13 secteurs d'étude. Les analyses ont fournie une forte preuve que les populations sur les secteurs d'étude de Wenatchee, Cle Elum, Rainier, Olympic, Warm Springs, H. J. Andrews, les chaînes la Côte d'Oregon et Simpson étaient en déclin pendant l'étude. La moyenne de λRJSpour les 13 secteurs d'étude était 0,963 (SE = 0,009), suggérant que les populations de chouettes de tous les secteurs déclinaient d'environ 3,7% par année pendant l'étude. La moyenne de λRJSpour les 8 secteurs de surveillance sur les terres fédérales était 0,976 (SE = 0,007) comparé à une moyenne de 0,942 pour les autres secteurs d'étude, environ 2,4 contre 5,8% de déclin par an. Ceci a suggéré que ces populations de chouettes sur les terres fédérales avaient de meilleurs taux démographique qu'ailleurs. A Washington, les populations de chouettes étaient les plus pauvres en nombre et le taux de survie apparent des populations était en déclin sur tous les 4 secteurs d'étude. Nos estimations de λRJSétaient généralement plus basses que celles reportées dans une analyse précédente (λRJS= 0,997, SE = 0,003) pour la plupart de ces mêmes régions à une date précédente. Les causes possibles de ces déclins de population inclues, mais pas exclusivement, à la perte d'habitat dû au déboisement et aux feux de brousse, la compétition avec les chouettes striées et les conditions climatiques. Ainsi le Projet Forestier Nord‐ouest de Forêt s'est avéré d'avoir un effet positif sur la démographie de chouettes tachetées septentrionales.

Because spotted owls (Strix occidentalis) are territorial, the theory of habitat selection predicts that they should occupy sites that are relatively dispersed. We examined this prediction using data from a long-term study by measuring the spatial dispersion of occupied sites within years, and the spatial dispersion of sites relative to their occupancy among years. We also examined how experience, based on individual origin (local or immigrant recruit), and age of individual, influenced settlement distance relative to already occupied sites. We estimated that occupied sites were more dispersed than expected by chance, and sites with similar occupancy rates were dispersed rather than clumped. However, immigrants tended to settle closer to already occupied sites compared to individuals that switched sites within the study area. This suggested that immigrants might have been using conspecifics as cues to settle in potentially suitable habitat. Such a pattern of settlement may have long-term consequences on population dynamics if spotted owls select sites based on something other than intrinsic quality. Further, these results also suggest spotted owls may be slow to re-colonize areas once they have been extirpated.

We have determined the structure of a capsular polysaccharide from Sinorhizobium fredii HWG35. This polysaccharide was isolated following the standard protocols applied for lipopolysaccharide isolation. On the basis of monosaccharide analysis, methylation analysis, mass spectrometric analysis, one-dimensional ¹H and ¹³C NMR, and two-dimensional NMR experiments, the structure was shown to consist of a polymer having the following disaccharide repeating unit:  →6)-2,4-di-O-methyl-α-d-Galp-(1→4)-β-d-GlcpA-(1→. Strain HWG35 produces a capsular polysaccharide that does not show the structural motif (sugar-Kdx) observed in those S. fredii strains that, while effective with Asiatic soybean cultivars, are unable to form nitrogen-fixing nodules with American soybean cultivars. Instead, the structure of the capsular polysaccharide of S. fredii HWG35 is in line with those produced by strains HH303 (rhamnose and galacturonic acid) and B33 (4-O-methylglucose-3-O-methylglucuronic acid), two S. fredii strains that form nitrogen-fixing nodules with both groups of soybean cultivars. Hence, in these three strains that effectively nodulate American soybean cultivars, the repeating unit of the capsular polysaccharide is composed of two hexoses, one neutral (methylgalactose, rhamnose, or methylglucose) and the other acidic (glucuronic, galacturonic, or methylglucuronic acid).

The performance of 4 serological tests for the diagnosis of Chagas disease was evaluated in Santander, Colombia, a region still presenting active transmission. Serum samples from 638 individuals were submitted to an enzyme immunoassay test (EIA), using total lysate of a local Trypanosoma cruzi strain and 52·5% were positive (335/638). A subset of this group (94 positive individuals and 90 seronegatives) was randomly selected for further serological confirmation. Three additional tests were used – indirect immunofluorescence (IIF) and 2 distinct enzyme-linked immunosorbent assays using total lysate of the Y strain (EIA BM) and a mixture of 2 recombinant antigens (EIA RA). Seventy-nine patients were seropositive in all tests (84·0% – 79/94). The number of positive sera with the IIF, EIA RA and EIA BM was 84/94 (89·4%), 80/94 (85·1%) and 79/94 (84·0%), respectively. In 15 out of the 94 EIA seropositive patients (16·0%), 10 individuals were negative in all 3 tests (10·6% – 10/94). One was negative in the EIA BM and positive in the other two tests (1·1% – 1/94) and 4 patients were positive, solely, in the IIF assay (4·3% – 4/94). Relative to the 90 EIA negative individuals, 89 were confirmed in all other tests (98·9% – 89/90). One individual, although seronegative in the IIF, was positive in both confirmatory EIA tests (1·1% – 1/90). In addition, 120 blood specimens were submitted to PCR amplification. This group consisted of 79 confirmed seropositive cases, 16 individuals with discordant serological results and 25 validated seronegative individuals. The PCR was able to detect the presence of parasite DNA in 67 out of the 79 seropositive patients (84·8%), in 8 individuals with discordant serology (50·0%) and in only one seronegative individual (4·0%). The results pointed to the necessity for performing more than one serological test, preferentially with antigens from autochthonous strains, to achieve a reliable diagnosis of Chagas disease in Colombia.

Describes the chemical effects of chlorides and sulfates on corrosion of carbon steel in semiarid tropical regions in Venezuela. Effects of wetness on corrosion; Climatic characteristics of the areas; Evaluation of atmospheric pollutants as chlorides and sulfates; Effects of pollutants on hydrosoluble salts in corrosion products.

Extracts of the whole plant Acaena magellanica(Rosaceae) were assessed for anti‐inflammatory, antipyretic and analgesic activity in animal models. At 600 mg kg−1, the global ethanolic extract (GEE), dichloromethane (DCM) and defatted methanol (MeOH) fractions showed a mild anti‐inflammatory effect in the carrageenan‐induced guinea‐pig paw oedema. The GEE, DCM and defatted MeOH fractions significantly reduced inflammation by 43.2, 40.5 and 42.1%, respectively. The GEE did not showed any significant antipyretic activity in doses up to 600 mg kg−1. A 20% w/v infusion administered orally at 16 mL kg−1presented analgesic effect in the acetic acid‐induced abdominal constriction test in mice. The GEE and MeOH extract of A. magellanicashowed free radical scavenging activity in the diphenylpicrylhydrazyl decolouration assay. Assay‐guided isolation led to quercetin, Q‐3‐O‐β‐D‐glucoside, Q‐3‐O‐β‐D‐galactoside, ellagic acid and catechin as the free radical scavengers. The saponins tormentic acid 28‐O‐β‐D‐galactopyranoside and 28‐O‐β‐D‐glucopyranoside were isolated from the polar extract. The structures were determined by spectroscopic methods.

A methanol extract of the bark of Bocconia arboreawas fractionated on silica gel and the fractions analysed using gas chromatography coupled with mass spectrometry (GC‐MS). Several benzophenanthridine alka‐loids were identified including dihydrosanguinarine, oxysanguinarine, 11‐acetonyldihydrochelerythrine, dihydrochelerythrine, chelerythrine, chelerythridimerine and angoline as the principal constituents. The results show that the direct GC‐MS analysis of these alkaloids is possible with a clear distinction between the compounds. The technique is shown to be a valuable tool and an alternative technique to classical phytochemical procedures permitting the fast analysis of alkaloids mixtures. Copyright © 2002 John Wiley & Sons, Ltd.

The aim of the present study was to determine if signal-averaged ECG of patients with anthracycline-induced left ventricular dysfunction could differentiate between patients with anthracycline-induced cardiotoxicity and those without. Sixteen children with anthracycline-induced cardiomyopathy, aged 6.5 to 15.5 years (anthracycline dose = 198-737 mg/m2), and 31 patients aged 5.0 to 16.7 years, who received anthracyclines without evidence of left ventricular dysfunction (anthracycline dose = 120-517 mg/m2), were studied with signal averaged ECG. The two groups were comparable in age, body surface area, and time since completion of chemotherapy. Signal averaged ECG parameters of the patients were compared with data obtained from 530 healthy children. These parameters were converted to z-scores to account for growth-related changes in signal averaged ECG recordings. Z-scores for filtered QRS duration and low amplitude terminal signal < 40 mV were significantly lower (p = 0.002 and p = 0.015, respectively), and Z-score for root mean square voltage of the last ?30 ms of filtered QRS tended to be higher (p = 0.06) in patients with left ventricular dysfunction. Filtered QRS duration lower than ?1.5 SD was found in 4 of 16 patients with left ventricular dysfunction and in only 1 of 31 patients without (p < 0.05) yielding a sensitivity of 25% and a specificity of 97% to detect left ventricular dysfunction. Only 1 patient had late potentials; his left ventricular function was normal. Left ventricular mass index tended to be lower in patients with left ventricular dysfunction (p = 0.07), whereas left ventricular diastolic diameter was similar in the two groups. The mechanism that accounted for the difference in signal averaged-ECG between the two groups of patients could be linked with the decrease in left ventricular mass in patients with left ventricular dysfunction. In conclusion, children with left ventricular dysfunction following anthracycline therapy have a SA ECG different from those without left ventricular dysfunction, which is mainly characterized by a lower filtered QRS duration. A prospective study is needed in order to determine if this modification of SA ECG recordings precedes alteration of left ventricular function, and, therefore, if it could help in early detection of cardiac toxicity of anthracyclines.

A review is given of the results of first principles calculations used to investigate the structures and electronic properties of screw and edge dislocations in GaN. The atoms at the core of the full core screw dislocation possess heavily strained bonds leading to deep gap states. Removing the first shell of Ga and N atoms gives a screw dislocation with a small open core consisting of {101-0} type surfaces. Therefore open-core screw dislocations induce only shallow gap states. In the same way we found the core of the threading edge dislocation to be reconstructed without any deep states. The interaction of oxygen with the cores of open-core screw and edge dislocations is considered and it is found that the impurity has a strong tendency to be bound by Ga vacancies leading to three types of defect trapped in the strain field. We suggest that the most stable defect leads to a poisoning of growth centres on the walls of nanopipes.

The laser desorption of Ck (k = 60 and 70) fullerene is known to produce a broad distribution of cluster sizes strongly peaking around the integer multiples of original fullerene mass. The “exact dimers” (Cn clusters with n = 2k) and species with slightly fewer atoms (n even) have been characterized previously as fully coalesced large single-shell fullerenes and [2 + 2] cycloadducts. Presently, we investigate the species encountered on the high-mass sides of exact dimers, that is, the clusters with n > 2k (n even), using high-resolution ion mobility measurements. Specifically, the drift time distributions for Cn⁺ and Cn^- with n = 122−128, 132−136, and 142−146 have been obtained and compared with the results of trajectory calculations for various trial geometries optimized using the density functional tight binding and semiempirical (AM1) calculations. We find that, besides the normal near-spherical fullerenes and [2 + 2] cycloadducts, these species assume the “ball-and-chain” structures consisting of two fullerene cages (not necessarily those of the original material) connected by chains up to eight atoms long. C122 and C132 cations and anions also reveal a substantial abundance of isomers where the C−C unit is sandwiched between the two fullerenes. Taken in conjunction with earlier findings for smaller fullerene dimers, presently reported results have allowed us to develop a comprehensive model for the chemical reactions occurring in the hot fullerene plasma.

We have developed a quantitative PCR-ELISA for the rapid enumeration of bacteria in refrigerated raw milk using primers designed from conserved regions in the 16S ribosomal RNA gene (rRNA). The designed primers permitted the amplification of a 147 bp DNA fragment from a wide selection of bacteria which may grow in milk at refrigeration temperatures. Amplified PCR products generated using a digoxigenin-labelled primer were heat-denatured before being quantified by an enzyme-linked immunosorbent assay (ELISA). A biotinylated probe immobilized onto streptavidin-coated microplates was used to capture the digoxigenin-labelled fragments that were detected with a peroxidase anti-digoxigenin conjugate. Subsequent enzymic conversion of substrate gave distinct absorbence differences when assaying milk samples containing bacteria in the range 103-107 cfu ml-1. The detection threshold for thePCR-ELISA assay developed in this work is 103 cfu ml-1.

Monoclonal antibodies generated against live cells of Pseudomonas fluorescenshave been used in an indirect ELISA format for the detection of Pseudomonasspp. in refrigerated meat. The detection threshold for the ELISA assay developed in this work was 104cfu cm−2.

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Two methods are introduced for the solution of free vibration problems of rectangular plates having nonuniform, elastic edge constraints, a class of problems having no previous solutions in the literature. One method uses exact solutions to the governing differential equation of motion, and the other is an extension of the Ritz method. Numerical results are presented for problems having parabolically varying rotational constraints.