884 resultados para Affecting factors


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Includes bibliography

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Brazil occupies an outstanding position as a producer and exporter of chicken meat, and the maintenance and expansion of this position require a constant evolution, especially in variables which determine quality. An important quality parameter of poultry meat is the amount of water absorbed by the carcass during processing. In Brazil, carcasses chilling is done by immersion in chilled water. In this process, the carcass is rehydrated and the water lost during transport and initial operations is replaced. At this stage, some care is needed to prevent the absorption of water upper than the level allowed by Brazilian law. This project aimed to evaluate extrinsic factors that can influence the absorption of water by the chicken meat. For this, 144 Cobb chickens divided into 24 groups of six birds were used. At 42 days of age, one chicken of each group, with weight ranging up to 10% more or less from the average of the group, was slaughtered in an experimental pilot scale abattoir where slaughter procedures were conducted under strictly controlled conditions. The chilling procedure was performed following a completely randomized design with factorial arrangement 3x2, where the factors were: three temperatures in the first section of the chilling system (4, 10 and 16ºC) and two degrees of water hardness (hard and soft water), with six treatments and four replications. Brazilian law provides that the water temperature in the first section of the chiller must not be higher than 16ºC, and the length of the carcasses in this section shall not exceed 30 minutes. All carcasses remained in the first section of the chiller for 30 minutes and then were transferred to another tank with water at 4ºC, remaining there until reaching 7ºC. The carcasses were weighed before and after chilling, to evaluate the percentage of water absorbed. The water absorption was influenced by the initial temperature of the water in the chiller and by the water hardness. When initially immersed in water at 4ºC, carcasses water absorption averaged 2.70%, a significantly lower absorption than the values found for the carcasses that were initially immersed in water at 16ºC, 3.83% (p<0.05). The carcasses immersed in water at 10ºC had mean water absorption of 3.66%, not differing from the means observed in the other two treatments (p>0.05). In hard water, the average water absorption was 2.46% and, in soft water, 4.33% (p<0.05). In all treatments, the water absorption did not exceed the limit established by Brazilian legislation, which is a maximum of 8%. This information is important to control the absorption of water by carcasses in chicken meat processing, preventing consumers from being harmed.

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Domestic cats (Fells catus) are widely believed to be highly sensitive to the effects of social stress, especially when living in high density populations. Cats are capable of adapting to living in a group, but this will often require opportunities for escaping and hiding. In this pilot study, adrenocortical activity, as a valuable physiological indicator of arousal underpinning potential emotional stress, was evaluated through the measurement of mean faecal glucocorticoid metabolites (mGCM) in fourteen singly and sixteen group-housed cats. Living conditions and ratings of the owners' quality of life (evaluated from self-reported questionnaires) were used as factors associated with faecal glucocorticoid levels of the cats. A direct association between the scores of owners' social dimension of quality of life and the cats' mGCM was found for single cats only, with higher owner social scores associated with higher cat mGCM. No significant differences in mGCM were found between singly versus group-living cats. This suggests that the under-explored factor of owner lifestyle could play an important role in domestic cats' day-to-day levels of arousal, especially when kept as single pets.

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Strain ST211CH, identified as a strain of Enterococcus faecium, isolated from Lombo produced a bacteriocin that inhibited the growth of Enterococcus spp., Listeria spp., Klebsiella spp., Lactobacillus spp., Pseudomonas spp., Staphylococcus spp. and Streptococcus spp. The mode of action of the bacteriocin named as bacteriocin ST211Ch was bactericidal against Enterococcus faecalis ATCC19443. As determined by Tricine-SDS-PAGE, the approximate molecular mass of the bacteriocin was 8.0 kDa. Loss in antimicrobial activity was recorded after treatment with proteolytic enzymes. Maximum activity of bacteriocin ST211Ch was measured in broth cultures of E. faecium strain ST211Ch after 24 h; thereafter, the activity was reduced. Bacteriocin ST211Ch remained active after exposure to various temperatures and pHs, as well as to Triton X-100, Tween-80, Tween-20, sodium dodecyl sulfate, NaCl, urea and EDTA. Effect of media components on production of bacteriocin ST211Ch was also studied. On the basis of PCR reactions targeting different bacteriocin genes, i.e. enterocins, curvacins and sakacins, no evidences for the presence of these genes in the total DNA of E. faecium strain ST211Ch was obtained. The bacterium most probably produced a bacteriocin different from those mentioned above. Based on the antimicrobial spectrum, stability and mode of action of bacteriocin ST211CH, E. faecium strain ST211Ch might be considered as a potential candidate with beneficial properties for use in biopreservation to control food spoilage bacteria.

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The exact mechanisms of the exercise induced adaptations is not lucid, but recent studies have delineated two means of signaling by which the adaptations occur (1) substrate availability signaling (metabolic stress) (2) hormone-receptor signaling. We have decided to specifically investigate two metabolic signaling enzymes [AMP-activated kinase (AMPK) and Sirtuin 1(SIRT1)] and two hormones [Adiponectin and Adrenergic stimulation].Tis based on four papers with the following conclusions: (1)Increase in SIRT1 activity and expression in H9c2 cells treated with phenylephrine is an adaptive response to the hypertrophic stress, mediated by AMPK. (2)The lack of optimal nutritional conditions (energetic substrates) due to a prolonged activation of AMPK can contrast the establishment of hypertrophy, possibly also by means of the negative modulation of ODC activity. (3) Our findings offer a possibile hypothesis as to the fact the the G allele on site 45 could lead to the increasd risk of Type II diabetes through a decrease in lean body mass. (4) Our results suggest that there is an ADIPOQ gene effect in relation to bone parameters. Statistical analysis show that the presence of the T allele in position 45 favors an increase in lumbar spine bone mineral content (BMC) when compared to subjects with a G allele substitution, which can be do the the increase in lean body mass in this genotype group.

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Computer modeling of 10 patients' computed tomographic scans was used to study the variables affecting hip arthroplasty range of motion before bony impingement (ROMBI) including acetabular offset and height, femoral offset, height and anteversion, and osteophyte removal. The ROMBI was compared with the ROM before component impingement and the native hip ROM. The ROMBI decreased with decreased total offset and limb shortening. Acetabular offset and height had a greater effect on ROMBI than femoral offset and height. The ROMBI lost with decreased acetabular offset was not fully recoverable with an increase in femoral offset or osteophyte removal. Bony impingement increased and component impingement decreased with decreased acetabular offset and increased head diameter.

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The aim was to investigate the efficacy of neoadjuvant docetaxel-cisplatin and identify prognostic factors for outcome in locally advanced stage IIIA (pN2 by mediastinoscopy) non-small-cell lung cancer (NSCLC) patients. In all, 75 patients (from 90 enrolled) underwent tumour resection after three 3-week cycles of docetaxel 85 mg m-2 (day 1) plus cisplatin 40 or 50 mg m-2 (days 1 and 2). Therapy was well tolerated (overall grade 3 toxicity occurred in 48% patients; no grade 4 nonhaematological toxicity was reported), with no observed late toxicities. Median overall survival (OS) and event-free survival (EFS) times were 35 and 15 months, respectively, in the 75 patients who underwent surgery; corresponding figures for all 90 patients enrolled were 28 and 12 months. At 3 years after initiating trial therapy, 27 out of 75 patients (36%) were alive and tumour free. At 5-year follow-up, 60 and 65% of patients had local relapse and distant metastases, respectively. The most common sites of distant metastases were the lung (24%) and brain (17%). Factors associated with OS, EFS and risk of local relapse and distant metastases were complete tumour resection and chemotherapy activity (clinical response, pathologic response, mediastinal downstaging). Neoadjuvant docetaxel-cisplatin was effective and tolerable in stage IIIA pN2 NSCLC, with chemotherapy contributing significantly to outcomes.

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The present study was conducted to determine the effects of different variables on the perception of vehicle speeds in a driving simulator. The motivations of the study include validation of the Michigan Technological University Human Factors and Systems Lab driving simulator, obtaining a better understanding of what influences speed perception in a virtual environment, and how to improve speed perception in future simulations involving driver performance measures. Using a fixed base driving simulator, two experiments were conducted, the first to evaluate the effects of subject gender, roadway orientation, field of view, barriers along the roadway, opposing traffic speed, and subject speed judgment strategies on speed estimation, and the second to evaluate all of these variables as well as feedback training through use of the speedometer during a practice run. A mixed procedure model (mixed model ANOVA) in SAS® 9.2 was used to determine the significance of these variables in relation to subject speed estimates, as there were both between and within subject variables analyzed. It was found that subject gender, roadway orientation, feedback training, and the type of judgment strategy all significantly affect speed perception. By using curved roadways, feedback training, and speed judgment strategies including road lines, speed limit experience, and feedback training, speed perception in a driving simulator was found to be significantly improved.

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OBJECT: The aim of this study was to identify patients likely to develop CSF leaks after vestibular schwannoma surgery using a retrospective analysis for the identification of risk factors. METHODS: Between January 2001 and December 2006, 420 patients underwent retrosigmoidal microsurgical tumor removal in a standardized procedure. Of these 420 patients, 363 underwent treatment for the first time, and 27 suffered from recurrent tumors. Twenty-six patients had bilateral tumors due to neurofibromatosis Type 2, and 4 patients had previously undergone radiosurgical treatment. An analysis was performed to examine the incidence of postoperative CSF fistulas in all 4 groups. RESULTS: The incidence of CSF leakage was higher in the tumor recurrence group (11.1%) than in patients undergoing surgery for the first time (4.4%). There were no CSF fistulas in the neurofibromatosis Type 2 group or in patients with preoperative radiosurgical treatment. Tumor size was identified as a possible risk factor in a previous study. CONCLUSIONS: Surgery for recurrent tumors is a significant risk factor for the development of CSF leaks.

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Background and aim. Hepatocellular carcinoma (HCC) is a frequent cancer. Its prognosis is highly dependent on early diagnosis. Patients at risk for developing HCC should be enrolled in a surveillance programme. Nevertheless, many patients at risk are not regularly screened. We aimed at exploring the characteristics that affect enrolment in a surveillance programme. Material and methods. The characteristics of the patients included in the prospective Bern HCC cohort between August 2010 and August 2011 were analysed according to their participation in a surveillance programme. Results. Among the 82 patients included in the cohort during this period of time, 48 were in a surveillance program before the diagnosis of HCC. Thirty five percent of cirrhotic patients were not screened. Age, sex, level of education, Child-Pugh status and MELD score were similar between the patients who were screened and those who were not screened. Patients with a private insurance and patients treated by a liver specialist were more frequently enrolled in a surveillance program. Sixty seven percent of the screened patients were eligible for curative treatment whereas only 15% of the non-screened patients were. Conclusions. In conclusion the surveillance of patients at risk for developing HCC increases their chances to be diagnosed at an early stage to allow curative treatment. More than one third of cirrhotic patients were not regularly screened. Patients with chronic liver disease should be referred to identify those at risk and enrol them in a surveillance program.

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The in vitro conversion of phosphatidylglycerophosphate (PGP) to phosphatidylglycerol (PG) involves at least two membrane bound phosphatases in Escherichia coli. The genes encoding these two PGP-phosphatases, pgpA and pgpB, are unique and map distally to min 10 and min 28 respectively. Although point mutations in either or both of these genes decrease the level of PGP phosphatase as assayed in vitro, and also result in a minor accumulation of the precursor, PGP, in the membrane, the mutations have no significant effect on the level of PG in the cell (Icho, T. and Raetz, C. R. H. (1983) J. Bact. 153, 722-730). This dilemma suggests that there remains a significant level of phosphatase activity in the pgpAand pgpB mutants which is sufficient to support normal PG metabolism in vivo, but it is not clear whether this activity is a consequence of a separate phosphatase, or due to "leakiness" of the point lesions in these genes. To address this problem, we have constructed null alleles of the two phosphatase genes, and characterized the effects of these mutations on PG metabolism. Our findings demonstrate that neither the pgpA nor the pgpB phosphatase gene is essential for cell viability. In addition, similar to the pgpA$\sp{-}$, pgpB$\sp{-}$ double point mutant, a strain containing both of the corresponding null alleles still retains enough phosphatase activity to maintain normal levels of PG in the membrane. These data demonstrate that there exists at least a third gene encoding a major biosynthetic phosphatase which is responsible for the in vivo conversion of PGP to PG, and calls into question the actual roles of the pgpA and the pgpB gene products in PG metabolism and cell function. ^

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Technological advances in gear and fishing practices have driven the global expansion of the American lobster live seafood market. These changes have had a positive effect on the lobster industry by increasing capture efficiency. However, it is unknown what effect these improved methods will have on the post-capture fitness and survival of lobsters. This project utilized a repeated measures design to compare the physiological changes that occur in lobsters over time as the result of differences in depth, hauling rate, and storage methodology. The results indicate that lobsters destined for long distance transport or temporary storage in pounds undergo physiological disturbance as part of the capture process. These changes are significant over time for total hemocyte counts, crustacean hyperglycemic hormone, L-lactate, ammonia, and glucose. Repeated measures multivariate analysis of variance (MANOVA) for glucose indicates a significant interaction between depth and storage methodology over time for non-survivors. A Gram-negative bacterium, Photobacterium indicum, was identified in pure culture from hemolymph samples of 100% of weak lobsters. Histopathology revealed the presence of Gram-negative bacteria throughout the tissues with evidence of antemortem edema and necrosis suggestive of septicemia. On the basis of these findings, we recommend to the lobster industry that if a reduction in depth and hauling rate is not economically feasible, fishermen should take particular care in handling lobsters and provide them with a recovery period in recirculating seawater prior to land transport. The ecological role of P. indicum is not fully defined at this time. However, it may be an emerging opportunistic pathogen of stressed lobsters. Judicious preemptive antibiotic therapy may be necessary to reduce mortality in susceptible lobsters destined for high-density holding facilities.