936 resultados para 3-21


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The response of soybean (Glycine max) and dry bean (Phaseolus vulgaris) to feeding by Helicoverpa armigera during the pod-fill stage was studied in irrigated field cages over three seasons to determine the relationship between larval density and yield loss, and to develop economic injury levels. H. armigera intensity was calculated in Helicoverpa injury equivalent (HIE) units, where 1 HIE was the consumption of one larva from the start of the infestation period to pupation. In the dry bean experiment, yield loss occurred at a rate 6.00 ± 1.29 g/HIE while the rates of loss in the three soybean experiments were 4.39 ± 0.96 g/HIE, 3.70 ± 1.21 g/HIE and 2.12 ± 0.71 g/HIE. These three slopes were not statistically different (P > 0.05) and the pooled estimate of the rate of yield loss was 3.21 ± 0.55 g/HIE. The first soybean experiment also showed a split-line form of damage curve with a rate of yield loss of 26.27 ± 2.92 g/HIE beyond 8.0 HIE and a rapid decline to zero yield. In dry bean, H. armigera feeding reduced total and undamaged pod numbers by 4.10 ± 1.18 pods/HIE and 12.88 ± 1.57 pods/HIE respectively, while undamaged seed numbers were reduced by 35.64 ± 7.25 seeds/HIE. In soybean, total pod numbers were not affected by H. armigera infestation (out to 8.23 HIE in Experiment 1) but seed numbers (in Experiments 1 and 2) and the number of seeds/pod (in all experiments) were adversely affected. Seed size increased with increases in H. armigera density in two of the three soybean experiments, indicating plant compensatory responses to H. armigera feeding. Analysis of canopy pod profiles indicated that loss of pods occurred from the top of the plant downwards, but with an increase in pod numbers close to the ground at higher pest densities as the plant attempted to compensate for damage. Based on these results, the economic injury levels for H. armigera on dry bean and soybean are approximately 0.74 HIE and 2.31 HIE/m2, respectively (0.67 and 2.1 HIE/row-m for 91 cm rows).

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The Executive Committee of the International Committee on Taxonomy of Viruses (ICTV) has recently decided to modify the current definition of virus species (Code of Virus Classification and Nomenclature Rule 3.21) and will soon ask the full ICTV membership (189 voting members) to ratify the proposed controversial change. In this discussion paper, 14 senior virologists, including six Life members of the ICTV, compare the present and proposed new definition and recommend that the existing definition of virus species should be retained. Since the pros and cons of the proposal posted on the ICTV website are not widely consulted, the arguments are summarized here in order to reach a wider audience.

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Esophageal atresia (EA), a common congenital anomaly comprising interrupted esophagus with or without a tracheoesophageal fistula (TEF), affects one in 2840 newborns. Over half have associated anomalies. After EA repair in infancy, gastroesophageal reflux (GER) and esophageal dysmotility and respiratory problems are common. As there exist no previous population-based long-term follow-up-studies on EA, its long-term sequelae are unclear. The aims of this study were to assess the cancer incidence (I), esophageal morbidity and function (II), respiratory morbidity (III), and the spinal defects (IV) in adults with repaired EA. All patients treated for EA at the Hospital for Children and Adolescents, University of Helsinki, from 1947 to 1985 were identified, and those alive with their native esophagus were contacted, and the first hundred who replied made up the study group. The patients were interviewed, they filled in symptom questionnaires, and they underwent esophageal endoscopy and manometry, pulmonary function tests, and a full orthopedic evaluation was performed with radiographs of the spine. The questionnaire was also sent by mail to adults with repaired EA not attending the clinical study, and to 287 general population-derived controls matched for age, gender, and municipality of residence. Incidence of cancer among the study population was evaluated from the population-based countrywide cancer registry. 169 (72%) adults with repaired EA replied; 101 (42%) (58 male) participated in the clinical studies at a median age of 36 years (range, 22-56). Symptomatic GER occurred in 34% and dysphagia in 85% of the patients and in 8% and 2% of the controls (P<0.001 for both). The main endoscopic findings included hiatal hernia (28%), Barrett´s esophagus (11%), esophagitis (8%), and stenotic anastomosis (8%). Histology revealed esophagitis in 25 individuals, and epithelial metaplasia in another 21. At immunohistochemistry, CDX2-positive columnar epithelial metaplasia was present in all 21 individuals, and 6 of these also demonstrated goblet cells and MUC2 positivity. In all histological groups, GER and dysphagia were equally common (P=ns). Esophageal manometry demonstrated non-propagating peristalsis in most of the patients, and low ineffective pressure of the distal esophageal body in all. The changes were significantly worse in those with epithelial metaplasia (P≤0.022). Anastomotic complications (OR 8.6-24, 95%CI 1.7-260, P=0.011-0.008), age (OR 20, 95%CI 1.3-310, P=0.034), low distal esophageal body pressure (OR 2.6, 95%CI 0.7-10, P=0.002), and defective esophageal peristalsis (OR 2.2, 95%CI 0.4-11, P=0.014) all predicted development of epithelial metaplasia. Despite the high incidence of esophageal metaplasia, none of the EA patients had suffered esophageal cancer, according to the Finnish Cancer Registry. Although three had had cancer (SIR, 1.0; 95% CI, 0.20-2.8). The overall cancer incidence among adults with repaired EA did not differ from that of the general Finnish population. Current respiratory symptoms occurred in 11% of the patients and 2% of the controls (P<0.001). Of the patients, 16%, and 6% of the controls had doctor-diagnosed asthma (P<0.001). A total of 56% and 70% of the patients and 20% and 50% of the controls had a history of pneumonia and of bronchitis (P<0.001 for both). Respiratory-related impaired quality of life was observable in 11% of the patients in contrast to 6% of the controls (P<0.001). PFT revealed obstruction in 21 of the patients, restriction in 21, and both in 36. A total of 41 had bronchial hyper-responsiveness (BHR) in HCT, and 15 others had an asthma-like response. Thoracotomy-induced rib fusion (OR 3.4, 95%CI 1.3-8.7, P=0.01) and GER-associated epithelial metaplasia in adulthood (OR 3.0, 95%CI 1.0-8.9, P=0.05) were the most significant risk factors for restrictive ventilatory defect. Vertebral anomalies were evident in 45 patients, predominating in the cervical spine in 38. The most significant risk factor for the occurrence of vertebral anomalies was any additional anomaly (OR 27, 95%C I8-100). Scoliosis (over 10 degrees) was observable in 56 patients, over 20 degrees in 11, and over 45 degrees in one. In the EA patients, risk for scoliosis over 10 degrees was 13-fold (OR 13, 95%CI 8.3-21) and over 20 degrees, 38-fold (OR 38, 95%CI 14-106) when compared to that of the general population. Thoracotomy-induced rib fusion (OR 3.6, 95%CI 0.7-19) and other associated anomalies (OR 2.1, 95%CI 0.9-2.9) were the strongest predictive factors for scoliosis. Significant esophageal morbidity associated with EA extends into adulthood. No association existed between the esophageal symptoms and histological findings. Surgical complications, increasing age, and impaired esophageal motility predicted development of epithelial metaplasia after repair of EA. According to our data, the risk for esophageal cancer is less than 500-fold that of the general population. However, the overall cancer incidence among adults with repaired EA did not differ from that of the general population. Adults with repaired EA have had significantly more respiratory symptoms and infections, as well as more asthma, and allergies than does the general population. Thoracotomy-induced rib fusion and GER-associated columnar epithelial metaplasia were the most significant risk factors for the restrictive ventilatory defect that occurred in over half the patients. Over half the patients with repaired EA are likely to develop scoliosis. Risk for scoliosis is 13-fold after repair of EA in relation to that of the general population. Nearly half the patients had vertebral anomalies. Most of these deformities were diagnosed neither in infancy nor during growth. The natural history of spinal deformities seems, however, rather benign, with spinal surgery rarely indicated.

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Nuoren märehtijän alkaessa syödä kiinteää ravintoa, etumahojen suhteellinen osuus mahoista kasvaa ja niiden seinämän epiteeli alkaa kehittyä mahdollistaakseen ravintoaineiden tehokkaan imeytymisen. Märehtijöillä rehun hiilihydraatit hajoavat pötsissä haihtuviksi rasvahapoiksi, ja monokarboksylaattikuljettajien uskotaan avustavan haihtuvien rasvahappojen imeytymisessä pötsin seinämän läpi. Pötsin seinämässä on todettu olevan ainakin MCT1- ja MCT4 –isoformeja. Nämä tarvitsevat toimiakseen CD147 -proteiinin (myös OX-47, EMMPRIN, HT7 ja basigin), joka on on glykosyloitu integraalinen membraaniproteiini. Tämän tutkimuksen tarkoituksena oli selvittää MCT1-, MCT4- ja CD147 –proteiinien muutoksia pötsin toiminnan kehittymisen aikana. Toisena tavoitteena oli selvittää, voidaanko näytteenä käyttää solukalvojen sijasta pötsin seinämästä tehtyä homogenaattia. Tutkimuksessa käytettiin eri ikäisinä lopetetuista kileistä kerättyjä näytteitä. Kilejä oli yhteensä 31, joista 7 oli 3-21 tunnin ikäisiä, 7 viikon ikäisiä, 7 kahden viikon ikäisiä, 1 kolmen viikon ikäinen, 2 neljän viikon ikäistä, sekä 7 kahdeksan viikon ikäistä. Pötsin seinämästä otettiin näyte, josta valmistettiin homogenaatti ja eristettiin solukalvot eli membraanit. Pötsinäytteistä löydettiin MCT1- ja CD147 –proteiineja, mutta MCT4- isoformia ei ollut havaittavissa. Membraaninäytteissä havaittiin MCT1 -isoformin pitoisuuksien kasvavan iän mukana, paitsi kahdeksan viikon ikäisillä kileillä, joilla MCT1 –isoformin määrät vähenivät merkitsevästi. CD147 –proteiinia oli havaittavissa jo vastasyntyneiden kilien pötsinäytteissä. Membraaninäytteissä CD147 -proteiinin määrä kasvoi lineaarisesti iän mukana ja CD147- proteiinin ja MCT1 –isoformin välillä havaittiin tilastollisesti merkitsevä korrelaatio. Homogenaattinäytteissä MCT1 -isoformin määrissä ei havaittu korrelaatiota iän kanssa. MCT1- ja MCT4 -isoformien solukalvolle siirtymisessä avustavan CD147 –proteiinin ei myöskään havaittu korreloivan koe-eläinten iän tai MCT1 -isoformin kanssa. Membraani- ja homogenaattinäytteistä mitattujen MCT1- ja CD147 -määrien välillä ei ollut korrelaatiota. Haihtuvien rasvahappojen muodostus alkaa, kun eläin aloittaa kiinteän ravinnon syömisen. Tästä seuraa, että haihtuvia rasvahappoja kuljettavia proteiineja tarvitaan epiteelisolujen pinnalle. Tutkimuksessa havaittiin haihtuvia rasvahappoja kuljettavan MCT1 –proteiinin ja sen apuproteiinien määrän lisääntyminen iän myötä. N. 8-11 viikon iässä, jolloin pötsin toiminta on kehittynyt aikuisen eläimen tasolle, MCT1 –proteiinin määrä oli merkitsevästi vähäisempi kuin 4 viikon iässä. Tulosten perusteella homogenaatti ei ole hyvä tapa mitata membraaniproteiinien määrää.

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The degradation kinetics of polycarbonate [poly(bisphenol A carbonate)] in benzene catalyzed by commercial (rutile) TiO2 (BET surface area = 11 m(2)/g), anatase TiO2 (156 m(2)/g), and 1 atom % Pt/TiO2 (111 m2/g), prepared by the solution combustion technique, was investigated at various temperatures (230-280 degreesC) and 50 atm. The time evolution of the molecular weight distribution (MWD) was determined by gel permeation chromatography (GPC) and modeled with continuous distribution kinetics to obtain the degradation rate coefficients. The rate coefficients for the catalytic degradation of polycarbonate increased by factors of 20, 3.5, and 1.3 compared to the rate coefficients for thermal degradation when catalyzed by nanosized TiO2 anatase, Pt/TiO2 anatase, and commercial TiO2, respectively, at 280 degreesC. The increased catalytic activity of combustion for synthesized TiO2 and 1% Pt/TiO2 might be due to the increased acidity and BET surface area. The activation energies, determined from the temperature dependencies of the rate coefficients, were 16.3, 21.5, and 39.1 kcal/mol for commercial TiO2, combustion-synthesized Pt/TiO2, and anatase TiO2, respectively.

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Con el objetivo de evaluar la Productividad y concentración de nutrientes del pasto cubano (Pennisetum purpureum x Pennisetum typhoides) cv CT – 115, se llevó a cabo la presente investigación en la finca Santa Rosa propiedad de la Universidad Nacional Agraria (UNA) Managua, Nicaragua. Localizada geográficamente a los 12° 08´ 33"de latitud norte y, 86° 10´ 31" de longitud oeste (INETER, 2006). Para ello se utilizó un área total de 33 m2 la cual se subdividió en tres parcelas de 10 m2 cada una donde se realizaron cortes cada 15 días hasta llegar a los 75 días. Se evaluaron las variables : altura, (cm) biomasa fresca (kg ha-1), Materia Seca (%), Biomasa seca (kg ha-1), Nitrógeno (%), Fósforo (%), Potasio (%),Calcio (%), Magnesio (%), Hierro (ppm), Manganeso (ppm), Zinc (ppm). Para la determinación de la producción de biomasa verde y seca (kg ha-1), se utilizó la metodología propuesta por la Red Internacional de evaluación de Pasturas Tropicales (CIAT, 1982). Para determinar los parámetros MS (%) se utilizó la metodología del análisis de Weende o análisis proximal (AOAC. 1990). Para el análisis de correlación se utilizo el programa SAS VERSION 9 para cada uno de las variables evaluadas, para la determinación de las curvas de mejor ajuste se utilizó el programa CVXP32. Durante el ensayo no se aplico ningún tipo de tratamiento agronómico (fertilización, riego). Los resultados obtenidos fueron: Altura 220 cm Biomasa fresca 31,764 kg ha-1 Materia seca 24% Biomasa seca 7529 kg ha-1. Las mayores concentraciones de nutrientes en la planta fueron: N 3.21% P 0.38% K 4.94% Ca 0.24% Mg 0.18% Fe 105.0ppm Mn 53.33ppm Zn 50ppm. Los modelos de mejor ajuste son: Modelo Múltiple Multiplicativo, Modelo Richards, Modelo Harris, Función Rotacional, Tercer Grado Polinomial y Asociación Exponencial.

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Con el objeto de evaluar el efecto de dos horas de corte (7 AM y 5 PM) y seis frecuencia de corte (25, 30, 35, 40, 45,50 días) sobre la composición química de planta entera y fracciones (hojas ramas y tallos) de Moringa oleifera Lam. Se realizó en la finca “El último bosque” propiedad del Sr. Nikolaus Foidl, localizada geográficamente entre la coordenadas 11º50 ́23 ̈ Latitud Norte y 86º 17 ́01 ̈ Longitud Oeste, en San Antonio de arriba, ciudad de Diriamba departamento de Carazo, de Abril a Noviembre del 2003. Las variables en estudio fueron: porcentaje de materia seca (%MS), porcentaje de proteína bruta (%PB), porcentaje de fibra bruta (%FB), porcentaje de lípidos totales (%LT). Además del rendimiento de biomasa fresca materia seca, proteína bruta, fibra bruta y lípidos totales. Se realizó análisis de varianza y comparaciones de media con la Prueba de rangos múl tiples (Tukey 5%) utilizando el programa SAS (v. 8.0), aplicando un diseño de parcelas divididas. Se encontró diferencia significativa (P>0.05) para el factor edad de corte en todos los tratamientos, a excepción de la variable lípidos totales en la que no ejerció ningún efecto significativo (P<0.05). El factor hora de corte solo ejerció efecto significativo sobre la variable porcentual materia seca, siendo la mejor hora de corte a las 5:00 PM. La interacción hora de corte – edad de corte no presento efecto significativo para ninguno de los tratamientos. Según la Prueba de rangos múltiples (Tukey 5%), se encontró que en las variables materia seca y fibra bruta los mejores resultados se logran a la edad de 50 días con 14.525 y 18.2125% respectivamente; para pr oteína bruta a la edad de 40 días con 22.678% y para lípidos totales a la edad de 45 días con 5.3725%. A 50 días se obtuvieron los más altos rendimientos de biomasa fresca, materia seca, proteína bruta, y fibra bruta con 209.05, 30.808, 5.5052 y 6.7430 (to n/ha/año) respectivamente; en lípidos totales a la edad de 45 días con 1.3641 (ton/ha/año). En la fracción hojas los mayores porcentajes de proteína se obtuvieron en la frecuencia de corte de 40 días con 33.54%, lípidos totales a los 45 días con 8.75% y ma teria seca a los 30 días con 19.30%. En la fracción ramas los mas altos porcentajes se logran al ser cosechadas a la edad de 30 días, obteniéndose un 12.03% de proteína, a los 45 días 3.21% de lípidos totales y a los 50 días 14.1% de materia seca. Mientras que en la fracción tallos los mejores valores de proteína y lípidos totales se logran a los 40 días, 12.06% y 2.56% respectivamente, en materia seca los mayores rendimientos porcentuales se logran a la edad de 40 y 50 días (11.7%)

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<正> 一、概况随着军事工业和普通工业的发展,射流和气动装置的应用越来越广泛,人们对空气源的净化(以下称“气源净化”)问题也有了进一步的认识。以前认为气源净化是不必要的奢侈品或加在气动系统上的多余组件,把它拆掉不用。直至一九六六年,使用者则不得不备有这些设备,因为受到损失的设备和发生故障的时间所引起的损失大大超过了气源净化设备的成本和维修费用。例如:据“Fluid Power

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发展了进气道布局的一维优化设计方法,从总体上把握进气道的设计构型,并对可移动中心锥进气道的关键几何参数进行优化选取。以确定的关键几何参数为基础,遵循相关准则进行了设计马赫数3.5的变几何轴对称进气道设计。并对超声速段与考虑吸气布局的进气道整体进行了数值模拟,分析了性能。实现了具有较好气动性能的变几何进气道的初步设计。

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Background: The aim of this study is to examine the influence of the catechol-O-methyltranferase (COMT) gene (polymorphism Val158 Met) as a risk factor for Alzheimer's disease (AD) and mild cognitive impairment of amnesic type (MCI), and its synergistic effect with the apolipoprotein E gene (APOE). A total of 223 MCI patients, 345 AD and 253 healthy controls were analyzed. Clinical criteria and neuropsychological tests were used to establish diagnostic groups. The DNA Bank of the University of the Basque Country (UPV-EHU) (Spain) determined COMT Val158 Met and APOE genotypes using real time polymerase chain reaction (rtPCR) and polymerase chain reaction (PCR), and restriction fragment length polymorphism (RFLPs), respectively. Multinomial logistic regression models were used to determine the risk of AD and MCI. Results: Neither COMT alleles nor genotypes were independent risk factors for AD or MCI. The high activity genotypes (GG and AG) showed a synergistic effect with APOE epsilon 4 allele, increasing the risk of AD (OR = 5.96, 95% CI 2.74-12.94, p < 0.001 and OR = 6.71, 95% CI 3.36-13.41, p < 0.001 respectivily). In AD patients this effect was greater in women. In MCI patients such as synergistic effect was only found between AG and APOE epsilon 4 allele (OR = 3.21 95% CI 1.56-6.63, p = 0.02) and was greater in men (OR = 5.88 95% CI 1.69-20.42, p < 0.01). Conclusion: COMT (Val158 Met) polymorphism is not an independent risk factor for AD or MCI, but shows a synergistic effect with APOE epsilon 4 allele that proves greater in women with AD.