876 resultados para ingestion cycle
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Abstract - This paper reviews existing military capability models and the capability life cycle. It proposes a holistic capability life-cycle model (HCLCM) that combines capability systems with related capability models. ISO 15288 standard is used as a framework to construct the HCLCM. The HCLCM also shows how capability models and systems relate to each other throughout the capability life cycle. The main contribution of this paper is conceptual in nature. The model complements the existing, but still evolving, understanding of the military capability life cycle in a holistic and systemic way. The model also increases understanding and facilitates communication among various military capability stakeholders.
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The objective of this study was to evaluate the effect of medroxy-progesterone acetate (MAP) with or without estradiol benzoate (EB) on follicular growth during the estrous cycle in cattle. In the first experiment, Hereford cows were synchronized with a synthetic analogue of PGF2 alpha and were treated with two different doses of MAP (250 or 500 mg) with or without EB for 7 days starting on day 8 of the estrous cycle. Follicular growth was inhibited (P<0.05) in all cows except controls and those receiving 250mg MAP without EB. Seventy-five percent of the animals (15/20) showed estrus on days 21 and 22 of the cycle rather than at MAP withdrawal, demonstrating that these treatments did not induce estrus. To determine whether the EB treatment altered endometrial sensitivity to oxytocin and thus the luteolytic cascade, multiparous pre-synchronized cows received 5 mg of EB followed 6 hours later with 50 IU of oxytocin (OT; n=9). Eight hours after EB injection, endometrial fragments were collected from the cows on days 4, 13 and 17 of the estrous cycle and COX-2 gene expression was measured by PCR. EB increased COX-2 mRNA levels only on day 17 of the estrous cycle (P<0.05). In conclusion, MAP alone or associated with EB is able to suppress bovine follicular growth. However, EB in the presence of MAP is not efficient to induce luteolysis in cows when injected on day 8 of the estrous cycle.
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Asclepias mellodora St. Hil. is a native acute toxic species frequent in the grasslands of the Buenos Aires province, Argentina, whose toxicity had not been assessed until now. This study evaluates the minimal lethal dose of this species for sheep, and the possibility of microscopically recognizing its fragments in gastrointestinal contents as a complementary diagnostic tool in necropsies. Three Frisona sheep (average LW=55±4.5 kg) were dosed via an esophageal tube with each one of the following doses of asclepias: 8.0, 5.0, 2.0 and 0.8 g DM.kg LW-1. Sheep poisoned with the three higher doses died between 10 and 85 h after intoxication, but those receiving the lower dose did not. During necropsies we: 1) determined the dry weight of the contents of rumen+reticulum, omasum+abomasum, and large intestine, 2) estimated the percentages of asclepias fragments by microanalysis correcting for digestion effects on fragment recognition, and 3) calculated the total mass of asclepias in the digestive tract of each animal. For the three higher doses, the mass of asclepias identified in the total ingesta was 12.3±3.4% of the amount supplied, possibly because of the strong diarrhea its ingestion produced. The percentages of asclepias in rumen+reticulum did not differ from the average quantified for the entire tract. The results of this study indicate that the minimal lethal doses of asclepias for sheep is between 2.0 and 0.8g DM·kg LW-1, and that the microhistological analysis of the rumen+reticulum, the easiest region to sample, can be used to confirm the ingestion of this toxic species, although the estimated percentage will be not a good estimator of the ingested percentage.
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Torque teno sus virus (TTSuV) infection is present in pig herds worldwide. It has been demonstrated that TTSuV might increase the severity of other important viral diseases with economic and public health impacts. At present, there is no information on the age distribution of pigs infected with TTSuV in Brazilian herds. This study evaluated the frequency of TTSuV infection in pigs at different stages of production. Fecal samples (n=190) from pigs at 1 to 24 weeks of age and from breeders at 6 farrow-to-weaning (up to 8 weeks of age) and 9 grower-to-finish (9 weeks of age onwards) farms in the western region of Paraná state, Brazil, were evaluated by PCR. Fragments of the 5' UTRs of TTSuV1 and/or TTSuVk2 DNAs were identified in 126 (66.3%) of the fecal samples. Significant differences were found with the percentages of positive samples for TTSuV1, TTSuVk2, and mixed infections by both genera between and within the different pig production stages. Fecal samples from the grower-to-finish farms had TTSuV detection rates (90.1%; 64/71) that were significantly (p<0.05) higher than those from the farrow-to-weaning farms (52.1%; 62/119). TTSuV detection was significantly (p<0.05) more frequent in finisher pigs than in the animals from the other stages. The UTR nucleotide sequences in this study presented higher similarities to strains from Norway (96%, TTSuV1), and Argentina and China (97.1%, TTSuVk2). These results suggest that TTSuV infection has spread to pigs of all production stages and that the viral infection rate increases with the age of the animals. In the western region of Paraná state, Brazil, TTSuV1 and TTSuVk2-induced infections were more frequently observed in suckling piglets and finisher pigs, respectively. Phylogenetic analysis pointed out the possibility of different strains of TTSuV1 and TTSuVk2 circulating in pig herds of Brazil.
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Studies are performed in developing techniques/procedures that provide greater reproductive performance in farm animals, including pigs. In this sense, the study of gilts reproductive organs at different oestrus cycle stages for assessing the presence of abnormalities and/or other parameters that may affect the future animal fertility is important. In order to evaluate the morphological, morphometric and histomorphometric features of ovaries, uterus and uterine tubes (UTs) characteristics of prepubertal gilts at different oestrus cycle stages, reproductive tracts from 48 animals immediately after slaughter were obtained. After, the structures were dissected and removed, and the ovaries were used for classification of oestrus cycle stage of each gilt in follicular phase (FP) and luteal phase (FL). Then, morphometric evaluations of ovaries, UTs, uterine horns and uterine body were performed. Besides that, medial segments of UTs and uterus were fixed in Bouin solution, processed and included in paraffin, when histological sections of 5.0 micrometers (µm) were obtained and stained with Hematoxylin and Eosin. Histomorphometric analyzes using image capture system and specific software were performed. Afterwards, data were submitted to Student's t test for assessment the statistical differences (P<0.05) between the two different oestrus cycle stages (FP × LP) and between the placement of reproductive structures (right × left antimer). Among the gilts evaluated, 35 were in the FP and 13 in LP. There was no difference (P>0.05) between morphometric parameters of ovaries, UTs and uterus of gilts in FP and LP. Likewise, in respect to the placement of reproductive structures, both in the oestrus cycle stages, as in the general average, there was no difference (P>0.05). Regarding the histomorphometric variables, gilts classified in FP presented a higher (P<0.05) height of glandular and UT epithelium compared to animals in LP. On the other hand, the diameter of endometrial glands was higher (P<0.05) in gilts at LP compared to FP. Furthermore, gilts in LP presented a higher (P<0.05) proportion of endometrium occupied by glands, whereas animals in FP had a higher (P<0.05) proportion of connective tissue and blood vessels. In conclusion, in prepubertal gilts, the histomorphometric parameters as endometrial glands diameter, the height of glandular epithelium and of UT epithelium and the proportion of endometrium occupied by connective tissue, besides the glands and blood vessels varies through the oestrus cycle, possibly under the influence of ovarian steroids.
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Collared peccaries (Peccary tajacu) are among the most hunted species in Latin America due the appreciation of their pelt and meat. In order to optimize breeding management of captive born collared peccaries in semiarid conditions, the objective was to describe and correlate the changes in the ovarian ultrasonographic pattern, hormonal profile, vulvar appearance, and vaginal cytology during the estrus cycle in this species. During 45 days, females (n=4) were subjected each three days to blood collection destined to hormonal dosage by enzyme immunoassay (EIA). In the same occasions, evaluation of external genitalia, ovarian ultrasonography and vaginal cytology were conducted. Results are presented as means and standard deviations. According to hormonal dosage, six estrous cycles were identified as lasting 21.0 ± 5.7 days, being on average 6 days for the estrogenic phase and 15 days for the progesterone phase. Estrogen presented mean peak values of 55.6 ± 20.5 pg/mL. During the luteal phase, the high values for progesterone were 35.3 ± 4.4 ng/mL. The presence of vaginal mucus, a reddish vaginal mucosa and the separation of the vulvar lips were verified in all animals during the estrogenic peak. Through ultrasonography, ovarian follicles measuring 0.2±0.1 cm were visualized during the estrogen peak. Corpora lutea presented hyperechoic regions measuring 0.4±0.2 cm identified during luteal phase. No significant differences (P>0.05) between proportions of vaginal epithelial cells were identified when comparing estrogenic and progesterone phases. In conclusion, female collared peccaries, captive born in semiarid conditions, have an estral cycle that lasts 21.0±5.7 days, with estrous signs characterized by vulvar lips edema and hyperemic vaginal mucosa, coinciding with developed follicles and high estrogen levels.
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The Galea spixii inhabits semiarid vegetation of Caatinga in the Brazilian Northeast. They are bred in captivity for the development of researches on the biology of reproduction. Therefore, the aim of this study is characterize the estrous cycle of G. spixii, in order to provide information to a better knowledge of captive breeding of the species. The estrous cycle was monitored by vaginal exfoliative cytology in 12 adult females. After the detection of two complete cycles in each animal, the same were euthanized. Then, histological study of the vaginal epithelium, with three females in each phase of the estrous cycle was performed; five were paired with males for performing the control group for estrous cycle phases, and three other were used to monitor the formation and rupture of vaginal closure membrane. By vaginal exfoliative cytology, predominance of superficial cells in estrus, large intermediate cells in proestrus, intermediate and parabasal cells, with neutrophils, in diestrus and metestrus respectively was found. Estrus was detected by the presence of spermatozoa in the control group. By histology, greater proliferation of the vaginal epithelium in proestrus was observed. We conclude that the estrous cycle of G. spixii lasts 15.8 ± 1.4 days and that the vaginal closure membrane develops until complete occlusion of the vaginal ostium, breaking after few days. Future studies may reveal the importance of this fact for the reproductive success of this animal.
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This study is a qualitative action research by its nature with elements of personal design in the form of a tangible model implementation framework construction. Utilized empirical data has been gathered via two questionnaires in relation to the arranged four workshop events with twelve individual participants. Five of them represented maintenance customers, three maintenance service providers and four equipment providers respectively. Further, there are two main research objectives in proportion to the two complementary focusing areas of this thesis. Firstly, the value-based life-cycle model, which first version has already been developed prior to this thesis, requires updating in order to increase its real-life applicability as an inter-firm decision-making tool in industrial maintenance. This first research objective is fulfilled by improving appearance, intelligibility and usability of the above-mentioned model. In addition, certain new features are also added. The workshop participants from the collaborating companies were reasonably pleased with made changes, although further attention will be required in future on the model’s intelligibility in particular as main results, charts and values were all reckoned as slightly hard to understand. Moreover, upgraded model’s appearance and added new features satisfied them the most. Secondly and more importantly, the premises of the model’s possible inter-firm implementation process need to be considered. This second research objective is delivered in two consecutive steps. At first, a bipartite open-books supported implementation framework is created and its different characteristics discussed in theory. Afterwards, the prerequisites and the pitfalls of increasing inter-organizational information transparency are studied in empirical context. One of the main findings was that the organizations are not yet prepared for network-wide information disclosure as dyadic collaboration was favored instead. However, they would be willing to share information bilaterally at least. Another major result was that the present state of companies’ cost accounting systems will definitely need implementation-wise enhancing in future since accurate and sufficiently detailed maintenance data is not available. Further, it will also be crucial to create supporting and mutually agreed network infrastructure. There are hardly any collaborative models, methods or tools currently in usage. Lastly, the essential questions about mutual trust and predominant purchasing strategies are cooperation-wise important. If inter-organizational activities are expanded, a more relational approach should be favored in this regard. Mutual trust was also recognized as a significant cooperation factor, but it is hard to measure in reality.
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Podisus nigrispinus is a generalist predator naturally occurring in agricultural and forestry systems that effectively contributes to the population balance of phytophagous insects, especially defoliating caterpillars. Histological changes were evaluated in the salivary glands and midgut of P. nigrispinus caused by ingestion of systemic herbicide isoxaflutole. These predator females were fed with leaves of eucalyptus plants, Tenebrio molitor pupae or water, contaminated or not by herbicide. Salivary glands and midguts were dissected, processed and analyzed under a light microscope. Activity level and cell morphology of the salivary glands and midgut showed differences among insects fed on plants, contaminated water or pupae. The epithelia of the salivary gland and midgut of individuals which had no contact with the herbicide showed homogeneous cytoplasm, nucleus with predominance of decondensed chromatin and evident nucleoli, intense cell activity features. As for the insects in contact with contaminated food, they presented undeveloped nucleus and condensed chromatin. The luminal contents of the salivary glands in the contaminated insects had become more acidophilus than in insects without poisoning, as well as having heterogeneous and granular secretion, being more evident in the bioassay in which the insects fed on contaminated water. There was a marked morphological change in the midgut cells in contaminated insects. High degree of apoptosis, disorganization and secretory vacuoles in the epithelial cytoplasm were observed. The apical portion of the midgut cells proved undeveloped, irregular and partially destroyed. It is concluded that isoxaflutole causes morphological changes in the digestive system of the predator P. nigrispinus.
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With the increasing concern of the sustainable approach of gold mining, thiosulphate has been researched as an alternative lixiviant to cyanide since cyanide is toxic to the environment. In order to investigate the possibility of thiosulphate leaching application in the coming future, life cycle assessment, is conducted to compare the environmental footprint of cyanidation and thiosulphate leaching. The result showed the most significant environmental impact of cyanidation is toxicity to human, while the ammonia of thiosulphate leaching is also a major concern of acidification. In addition, an ecosystem evaluation is also performed to indicate the potential damages caused by an example of cyanide spill at Kittilä mine, resulting in significant environmental risk cost that has to be taken into account for decision making. From the opinion collected from an online LinkedIn discussion forum, the anxiety of sustainability alone would not be enough to contribute a significant change of conventional cyanidation, until the tighten policy of cyanide use. International Cyanide Code, therefore, is crucial for safe gold production. Nevertheless, it is still thoughtful to consider the values of healthy ecosystem and the gold for long-term benefit.
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The effect of co-culturing varying concentrations of pig and human red blood cells (RBCs) on the baseline frequency of sister chromatid exchanges (SCEs) and cell-cycle progression in pig plasma (PLCs) and whole blood leukocyte cultures (WBCs) was studied. No variation in SCE frequency was observed between pig control WBC and PLC. Addition of pig and human RBCs to pig PLCs did not modify the baseline frequency of SCEs. On the other hand, cell proliferation was slower in PLCs than in WBCs. The addition of pig or human RBCs to PLCs accelerated the cell-cycle progression of pig lymphocytes. When RBCs were added to PLCs the concentration and time sequence of RBC incorporation affected the cell-cycle progression of swine lymphocytes. When doses of pig or human RBCs equivalent to those present in WBCs were added immediately after PLC stimulation, the cell-cycle kinetics were similar to those of WBCs. Shorter co-incubation periods or a reduction in the dose of RBCs made cell-cycle progression intermediate between PLC and WBC values. Thus, pig and human RBCs modulated the in vitro cell-cycle progression of pig lymphocytes in a time- and dose-dependent manner, and the low baseline frequency of SCEs of pig lymphocytes is independent of the presence or absence of erythrocytes in culture
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The aim of the present investigation was to extend a previous study, showing a correlation of the variations of hemolymph carbohydrates with synodic lunar-like cycle and its circaseptan harmonics to worker honeybee hemolymph lipids. Hemolymph lipid concentrations of emerging worker imagos were analyzed in terms of one ideal synodic lunar cycle and processed by the cosinor method testing the null hypothesis versus the presence of 29.5-, 14.8- or 7.4-day periods in the data. A rhythmicity statistically compatible with a 29.5-day rhythm was observed for triacylglycerols and steroids as well as for body weight. A circadiseptan rhythm was determined for 1,3 diacylglycerols, while fatty acids and phospholipids exhibited a circaseptan rhythm. An agreement of peaks for triacylglycerols, steroids and body weight at the new moon, but not at the full moon, was noted with respect to trehalose and glucose circadiseptan rhythms. The latter moon-phase timing of peaks and nadirs, compared with that previously determined for trehalose and glucose, appeared to be identical to the circadiseptan rhythm and reciprocal for the circaseptan rhythms of 1,3 diacylglycerols. Reciprocal tendencies in circaseptans of trehalose and glucose on the one hand, and fatty acids and phospholipids on the other are indicated. The underlying causal nexus of these relationships is unknown