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171.
de Souza Carneiro Adriana dos Santos Adriano Laviola Bruno Galvas Teodoro Larissa Pereira Ribeiro Teodoro Paulo Eduardo Rodrigues Erina Vitrio 《Genetic Resources and Crop Evolution》2022,69(1):245-254
Genetic Resources and Crop Evolution - Jatropha (Jatropha curcas L.) is an oleaginous potential, howetever, some studies report that there is low genetic diversity in Brazilian genotypes.... 相似文献
172.
María Teresa Gea Leiva Adriana Artola Casacuberta Antoni Sánchez Ferrer 《Compost science & utilization》2013,21(4):321-329
Evaluation of the parameters affecting the compostability of dewatered raw sludge from a wastewater treatment plant has been carried out by means of a full factorial composite experimental design. The factors and their correspondent levels considered in the experimental design were: bulking agent:sludge ratio (from 1:1 to 4:1 by volume), bulking agent particle size (from 0-5 mm to 10-20 mm) and composting volume (in the range of typical laboratory-scale, from 1.5 to 25 L). Experimental design has permitted obtaining a polynomial second-order function that quantitatively describes the influence of the considered factors on the compostability of this waste in laboratory reactors. The function has been numerically optimized to find the optimal values for composting raw sludge resulting in a values of: 0-5 mm for bulking agent size, 1:1 for ratio bulking agent:sludge and a composting volume around 10 L. The use of this technique can be generalized and applied to the composting of other organic wastes and will permit comparison of composting performance of different wastes. 相似文献
173.
Phenacoccus peruvianus Granara de Willink (Hemiptera: Pseudococcidae) is a new invasive mealybug that causes important damages in ornamental plants in urban landscapes and nurseries in Southern Europe. Recently, a new species of genus Acerophagus Smith (Hymenoptera: Encyrtidae) has been recorded as the main parasitoid of P. peruvianus in Spain, displacing the native parasitoid Leptomastix epona Walker (Hymenoptera: Encyrtidae). In this work, we have determined some traits of the reproductive and feeding strategies of Acerophagus sp.: fecundity, immature developmental time, host instar suitability, and preference when parasitizing P. peruvianus, and the effect of natural occurring sugar sources on adult longevity. Acerophagus sp. egg load reached its maximum when it was 5 days old. Second and third nymphal instars and adults were suitable for parasitism and immature development (efficient encapsulation was low). Immature development lasted between 20 and 22 days. Acerophagus sp. developed as a solitary parasitoid in the second instar and as a gregarious parasitoid in older instars (2–4 parasitoids per host). All the emerged offspring were females. Acerophagus sp. always preferred older instars when different host instars were available. Finally, adults lived more than 20 days when fed on honey, but they lived fewer than 3 days when fed on naturally occurring sugar sources (host honeydew and host plant flowers, Bougainvillea glabra). The consequences of these characteristics on biological control and parasitoid rearing are discussed. 相似文献
174.
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176.
Oswaldo Santos Gina Polo Rita Garcia Eduardo Oliveira Adriana Vieira Néstor Calderón Rudy De Meester 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(1):3-8
Dog population dynamics in shelters often requires the grouping of individuals, and changes to the composition of those groups. We developed a protocol to maximize the positive effects and reduce the negative effects associated with grouping dogs. Twenty-three neutered dogs that had to be grouped participated in the study. Fifteen were adult females, 7 were adult males, and 1 was a juvenile female. The protocol was divided into phases that allowed the use of environmental enrichment (occupational, social, nutritional, and sensorial) and behavioral modification (systematic desensitization and counter-conditioning). There were no fights involving bites during the formation of groups. In 5 (18.5%) of formed pairs, we observed unidirectional manifestations of aggression that did not involve physical contact. Three pairs (10%) could not be formed because we saw bidirectional aggression manifestation involving physical contact but no bites. The proposed protocol is a viable alternative to improve grouping of dogs in the context of shelters. The protocol also has the potential to promote wellness, enhance production of desirable behaviors, and decrease the presence of behavioral problems. 相似文献
177.
Effects of domestication on structural polysaccharides and dietary fiber in nopalitos (Opuntia spp.)
Cristian López-Palacios Cecilia Beatriz Pe?a-Valdivia J. Antonio Reyes-Agüero Adriana Inés Rodríguez-Hernández 《Genetic Resources and Crop Evolution》2012,59(6):1015-1026
Domestication is an evolutionary process that modifies morphological, physiological, chemical and genetic features of wild plants, and is a product of artificial selection. A gradient of domestication can be appreciated in species of the Opuntia genus. There are wild species like O. streptacantha, others semi-domesticated like O. hyptiacantha O. megacantha and O. albicarpa, or other like O. ficus-indica with the highest degree of domestication. At the same time, some structural polysaccharides have been associated with plant drought and freeze resistance. This study aimed at quantify five groups of structural polysaccharides in 14 variants of nopalitos (edible young cladodes of flat-stemmed spiny cacti consumed as vegetables) of Opuntia spp. in a domestication gradient. Given that extreme environment is less frequent under cultivation than in the wild, we hypothesized that structural polysaccharides in nopalitos are reduced throughout the domestication process. The experiment was conducted as a completely randomized design with a 5?×?14 two-factor factorial treatment structure, with four replications. Mucilages, pectins, hemicelluloses and cellulose were extracted and dietary fiber content was calculated. ANOVA of data was performed, pair wise comparisons of species and variants were conducted by Tukey test and principal components analysis was carried out. Mucilages were higher in O. ficus-indica (12% of total dry mass) and pectins, loosely and tightly bound hemicelluloses in O. streptacantha (2.5, 9 and 3%, respectively). All five species had similar content of cellulose (5.1% dry mass); but, O. streptacantha presented more dietary fiber. Higher pectins and both loosely and tightly bound hemicelluloses content in wild species can be related to genotype and the persistence of reaction to a wild environment. Mucilages which are one of the main characteristics of consumer preference and loosely bound hemicelluloses could have impact for selection during Opuntia domestication. 相似文献
178.
Smith DJ Barri A Herges G Hahn J Yersin AG Jourdan A 《Journal of agricultural and food chemistry》2012,60(12):3151-3157
Butyrate is a byproduct of microbial carbohydrate fermentation that occurs primarily in the large intestine. When added to feed, butyrate quickly disappears in the upper digestive tract. Because butyrate is important for epithelial cell development, mucosal integrity, and animal growth, an encapsulation technique has been developed that allows for the slow release of butyrate into the small and large intestines. The purpose of this study was to describe the in vitro release of calcium [1-(14)C]butyrate, formulated into a slow-release (protected) bead, into water and simulated intestinal fluids and to compare the in vivo absorption and disposition of unprotected versus protected calcium [1-(14)C]butyrate in broiler chicks. Formulation of calcium [1-(14)C]butyrate into protected beads allowed release of 5.8 ± 0.2 and 3.4 ± 0.2% of the formulated radiocarbon into water and gastric fluid, respectively, after 2 h of incubation. Beads incubated in gastric fluid for 2 h and subsequently incubated in simulated intestinal fluid released a total of 17.4 ± 0.8% of the formulated radioactivity. Release of respiratory [(14)C]CO(2) after oral dosing of aqueous calcium [1-(14)C]butyrate in broiler chicks peaked at 15.2 ± 5.2% per hour 1.5 h after dosing; in contrast, maximal rates of release in chicks dosed with protected calcium [1-(14)C]butyrate occurred 4 h after dosing at 9.0 ± 3.1% per hour. The data suggested an improved efficacy of protected butyrate delivery to intestinal tissues over nonprotected butyrate. This study confirmed that encapsulation strategies designed to enhance delivery of ingredients to improve intestinal health are effective at prolonging intestinal exposure to butyrate. Encapsulation of such ingredients might benefit the food and feed industries. 相似文献
179.
Lead is a well-known pollutant with documented toxicity. Lead-containing weights used to balance motor vehicle wheels are
regularly lost from vehicles and enter the environment. Lead weights deposited on roadways in the vicinity of Trenton, NJ
were gathered and measured from February 2006 to January 2009. Measurements included loss of mass from specific weights exposed
to traffic. Extrapolation of the results to the entire state suggests that approximately 12 tons per year of lead in the form
of wheel weights are deposited on New Jersey roadways, and that approximately 40 kg of lead enters the environment in the
form of small particles formed from the abrasion and grinding action of traffic on weights deposited on roadways. This quantity
of small particles is much less than the approximately 60 tons per year of lead estimated by an earlier study to enter New
Jersey in precipitation, some of which may result from the combustion of leaded aviation fuel. The quantity is also likely
small compared with the fluxes of lead into the environment that still continue from leaded paint and with the residue of
finely dispersed lead from historical uses of leaded gas in motor vehicles that remains in the environment. The quantity of
lead released to the environment in the form of wheel weights appears likely to decline in the future because of legislation,
voluntary phase-outs by manufacturers, and new trends in wheel technology 相似文献
180.
It is widely rec ognized that chitin and chitosan are potential sources of bioactive materials and that their oligosaccharides reveal various biological activities (including antimicrobial) that are correlated with their structures and physicochemical properties. This study uses the molecular docking approach to assess the interactions of small chito-oligosaccharides (MW< 1500 Da) with plasma proteins in order to obtain information regarding their fate of distribution in the human organism. There are favorable interactions of small chito-oligomers with plasma proteins, the interactions with human serum albumin being stronger than those with α-1-acid glycoprotein. The interaction energies increase with increasing the molecular weight, decrease with increasing deacetylation degrees and are reliant on the deacetylation pattern. This study could inform the application of chito-oligosaccharides with varying molecular weights, degrees, and patterns of deacetylation in human health. 相似文献