759 research outputs found
Porous glass-ceramics from alkali activation and sinter-crystallization of mixtures of waste glass and residues from plasma processing of municipal solid waste
Alkali-activated aqueous slurries of fine glass powders, mostly deriving from the plasma processing of municipal solid waste ('Plasmastone'), were found to undergo progressive hardening at low temperature (75 degrees C) owing to the formation of C-S-H (calcium silicate hydrate) gels. Before complete setting, slurries could be easily foamed by vigorous mechanical stirring, with the help of a surfactant; finally, the resulting open-celled structure could be 'frozen' by a subsequent sintering treatment, with crystallization of Ca-Fe silicates. The densification of the struts upon firing was enhanced by mixing Plasmastone with up to 30 wt% recycled glasses and increasing the firing temperature from 800 to 1000 degrees C. A total porosity exceeding 75 vol%, comprising both well-interconnected macro- and micro-sized pores on cell walls, was accompanied by good compressive strength, well above 1 MPa. The stabilization of pollutants generally increased with increasing firing temperature and glass content, with some exceptions; no practical leaching was observed from samples deriving from Plasmastone combined with 30 wt% boro-aluminosilicate glass from the recycling of pharmaceutical vials
Variation in egg size of the fresh-water prawn Macrobrachium amazonicum (Decapoda: Palaemonidae)
Egg size of the fresh-water prawn Macrobrachium amazonicum varied among ecologically isolated or geographically distant populations of the Amazon basin. The mean volume of both recently spawned nonpigmented eggs and older pigmented eyed eggs was smaller in prawns from the Tocantins River (0.14 and 0.20 mm3, respectively) than in those from the middle Amazon (0.17 and 0.25 mm3). The largest eggs (0.19 and 0.27 mm3) were displayed by females from the Iquitos and Guapore Rivers. Since the egg volume was independent of female body size, it was attributed to population specific characteristics. The egg size increased with the distance of the sampling site from the ocean, suggesting a progressive divergence of this species from a typical littoral population to an inland form, in a still active fresh-waterization process similar to the pattern evolved among other species in the genus Macrobrachium
Busca biodirigida por espécies vegetais com efeito inibitório da eclosão dos ovos de Haemonchus contortus
Tracing the history of South-American neotropical savannas and seasonally dry forests evidences from comparative phylogeography
Detecção da resistência parasitária para tratamento anti-helmíntico monitorado do rebanho ovino da Embrapa Pecuária Sudeste
ESTABILIDADE AERÓBIA DE CANA-DE-AÇÚCAR IN NATURA HIDROLISADA COM CAL VIRGEM
Objetivou-se com esta pesquisa avaliar o efeito da inclusão de cal virgem sobre a estabilidade aeróbia da cana-de-açúcar in natura. O trabalho foi conduzido na Faculdade de Zootecnia da UNIFENAS, sob delineamento experimental inteiramente casualizado, em esquema fatorial 4 x 5, avaliando-se quatro doses de cal (0,0; 0,5; 1,0 e 2,0 % em relação à matéria natural) e cinco tempos de exposição aeróbia (0, 12, 24, 48 e 72 horas após o momento da hidrólise), com quatro repetições. A inclusão do aditivo na cana-de-açúcar in natura provocou aumento no teor de matéria seca e nos valores de pH. Porém, os valores de pH diminuíram com o decorrer do tempo, em função da ação de microrganismos. Em relação à temperatura, esta aumentou quando se adicionou 1,0% de cal à cana-de-açúcar; no entanto, o menor valor referente ao acúmulo da temperatura durante as aferições foi obtido com a utilização de 2,0% de cal, e da mesma forma, a menor taxa de aquecimento foi obtida para este mesmo tratamento. De certa forma, a utilização de 2,0% de cal virgem aumentou a estabilidade aeróbia da cana-de-açúcar, porém, todos os tratamentos apresentaram instabilidade aeróbia poucas horas após o momento da mistura entre cal e cana-de-açúcar.
PALAVRAS-CHAVE: alcalinização; óxido de cálcio; pH; temperatura
Ruminal Fermentation of Sheep Fed Corn Silage Inoculated with Microbial Additives
An obligatory heterofermentative lactic acid bacteria (LAB), Lactobacillus buchneri, has been suggested as an additive to improve the aerobic stability of silages, mainly of corn silage, due to troubles during feedout of silos, when mishandled. Usually, heterolactic fermentation is deemed as undesirable compared with homolactic fermentation because the dry matter losses are greater. Otherwise, L. plantarum, a homo-fermentative LAB can be combined with L. buchneri in an attempt to decrease the fermentation losses and also protein degradation by greater production of lactate and, enhance the aerobic stability of silages. Nowadays, these LAB have been studied as their ability to change ruminal fermentation, well as to provide a probiotic effect. Thus, the aim was to evaluate the ruminal fermentation of sheep fed corn silage inoculated with L. buchneri alone or combined with L. plantarum
Reliabilität - die Genauigkeit einer Messung (Version 1.1)
Die Reliabilität beschreibt die Genauigkeit einer Messung. In diesem Beitrag wird das Konzept Reliabilität definiert und es wird erläutert, warum die Reliabilität einer Messung relevant ist. Danach wird diskutiert, welche Modellannahmen getroffen werden müssen, um die Reliabilität einer Messung zu schätzen und es werden fünf Methoden zum Schätzen der Reliabilität vorgestellt: die Re-Test Korrelation, die Parallel-Test Korrelation, die Split-Half Korrelation, die interne Konsistenz und das Schätzen der Reliabilität mit Strukturgleichungsmodellen. Abschließend wird in knapper Form auf Gemeinsamkeiten und Unterschiede der klassischen Testtheorie und der Item-Response Theorie und deren Bedeutung für die Schätzung der Reliabilität eingegangen
Hpv 16 Is Related To The Progression Of Cervical Intraepithelial Neoplasia Grade 2: A Case Series.
Purpose. To describe the acquisition, persistence, and clearance of HPV infection in women with CIN 2 followed up for 12 months. Methods. Thirty-seven women with CIN 2 biopsy, who have proven referral to cervical smear showing low-grade squamous intraepithelial lesions or atypical squamous cells of undetermined significance and tested for HPV, were followed up for one year with cervical smear, colposcopy, and HPV test every three months. HPV DNA was detected by the polymerase chain reaction and genotyping by reverse line blot hybridization assay. Results. CIN 2 regression rate was 49% (18/37), persistence as CIN 1 or CIN 2 was 22% (8/37), and progression to CIN 3 was 29% (11/37). Multiple HPV types were observed at admission in 41% (15/37) of cases. HPV 16 was detected at admission in 58% (11/19) of the cases that persisted/progressed and in 39% (7/18) of the cases that regressed. HPV 16 was considered possibly causal in 67% (10/15) of the cases that persisted or progressed and in 10% (1/10) of the cases that regressed (P = 0.01). Conclusion. Multiple HPV infections were frequently detected among women with CIN 2 at admission and during the followup. The CIN 2 associated with HPV 16 was more likely to persist or to progress to CIN 3.201332890
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