972 resultados para Site Selection


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Long-distance migratory birds are declining globally and migration has been identified as the primary source of mortality in this group. Despite this, our lack of knowledge of habitat use and quality at stopovers, i.e., sites where the energy for migration is accumulated, remains a barrier to designing appropriate conservation measures, especially in tropical regions. There is therefore an urgent need to assess stopover habitat quality and concurrently identify efficient and cost-effective methods for doing so. Given that fuel deposition rates directly influence stopover duration, departure fuel load, and subsequent speed of migration, they are expected to provide a direct measure of habitat quality and have the advantage of being measurable through body-mass changes. Here, we examined seven potential indicators of quality, including body-mass change, for two ecologically distinct Neotropical migratory landbirds on stopover in shade-coffee plantations and tropical humid premontane forest during spring migration in Colombia: (1) rate of body-mass change; (2) foraging rate; (3) recapture rate; (4) density; (5) flock size; (6) age and sex ratios; and (7) body-mass distribution. We found higher rates of mass change in premontane forest than in shade-coffee in Tennessee Warbler Oreothlypis peregrina, a difference that was mirrored in higher densities and body masses in forest. In Gray-cheeked Thrush Catharus minimus, a lack of recaptures in shade-coffee and higher densities in forest, also suggested that forest provided superior fueling conditions. For a reliable assessment of habitat quality, we therefore recommend using a suite of indicators, taking into account each species’ ecology and methodological considerations. Our results also imply that birds stopping over in lower quality habitats may spend a longer time migrating and require more stopovers, potentially leading to important carryover effects on reproductive fitness. Evaluating habitat quality is therefore imperative prior to defining the conservation value of newly identified stopover regions.

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The cytokine hormone leptin is a key signalling molecule in many pathways that control physiological functions. Although leptin demonstrates structural conservation in mammals, there is evidence of positive selection in primates, lagomorphs and chiropterans. We previously reported that the leptin genes of the grey and harbour seals (phocids) have significantly diverged from other mammals. Therefore we further investigated the diversification of leptin in phocids, other marine mammals and terrestrial taxa by sequencing the leptin genes of representative species. Phylogenetic reconstruction revealed that leptin diversification was pronounced within the phocid seals with a high dN/dS ratio of 2.8, indicating positive selection. We found significant evidence of positive selection along the branch leading to the phocids, within the phocid clade, but not over the dataset as a whole. Structural predictions indicate that the individual residues under selection are away from the leptin receptor (LEPR) binding site. Predictions of the surface electrostatic potential indicate that phocid seal leptin is notably different to other mammalian leptins, including the otariids. Cloning the grey seal leptin binding domain of LEPR confirmed that this was structurally conserved. These data, viewed in toto, support a hypothesis that phocid leptin divergence is unlikely to have arisen by random mutation. Based upon these phylogenetic and structural assessments, and considering the comparative physiology and varying life histories among species, we postulate that the unique phocid diving behaviour has produced this selection pressure. The Phocidae includes some of the deepest diving species, yet have the least modified lung structure to cope with pressure and volume changes experienced at depth. Therefore, greater surfactant production is required to facilitate rapid lung re-inflation upon surfacing, while maintaining patent airways. We suggest that this additional surfactant requirement is met by the leptin pulmonary surfactant production pathway which normally appears only to function in the mammalian foetus.

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Phosphine resistance in Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) has evolved through changes to enzymes involved in basic metabolic pathways. These changes impose metabolic stress and could affect energy-demanding behaviours. We therefore tested whether phosphine resistance alleles impact the movement of these insects in their quest for new resources. We measured walking and flight parameters of four T. castaneum genotypes: (1) a field-derived population, (2) a laboratory cultured, phosphine-susceptible reference strain, (3) a laboratory cultured, phosphine-resistant reference strain, and (4) a resistant introgressed strain that is almost identical genetically to the susceptible population. The temporal pattern of flight was identical across all populations, but resistant beetles took flight significantly less, walked more slowly, and located resources less successfully than did susceptible beetles. Also, the field-derived beetles (proved not to be carrying resistance genes) walked significantly faster and more directly towards food resources, and had a higher propensity for flight when compared to the susceptible laboratory beetles. These negative effects suggest survival of beetles with the resistance alleles will be compromised should they leave phosphine application sites. The field for selection therefore extends beyond the site at which phosphine fumigant imposed its effect, and other mutations are also likely to be affected in this way.

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Bien que l’os soit une matière première ayant joué un rôle essentiel au sein des activités quotidiennes des Iroquoiens du Saint-Laurent, il existe à ce jour très peu d’analyses systématiques de l’outillage en os et des débris de fabrication retrouvés en Iroquoianie. Afin de pallier ces lacunes, ce mémoire de maitrise porte sur l’analyse des vestiges en os ouvragés récupérés sur le site villageois Mailhot-Curran (BgFn-2), occupé durant le Sylvicole supérieur tardif par une communauté iroquoienne du Saint-Laurent. Plus précisément, l’étude consiste à analyser l’industrie osseuse en portant une attention particulière aux déchets de fabrication. Cet examen attentif a pour principal objectif de documenter les modes de gestion et de sélection de la matière première ainsi que d’améliorer la compréhension des techniques préhistoriques employées pour la fabrication des objets en os. Au moyen d’analyses technologiques, zooarchéologiques et tracéologiques, il sera possible de classifier les déchets de fabrication, de documenter leur origine technologique et, ultimement, de reconstituer un certain nombre de chaines opératoires. Une étude détaillée de la distribution spatiale des artéfacts permettra également de mieux comprendre l’organisation des activités dans l’espace villageois. Ce mémoire a aussi pour objectif de fournir des balises méthodologiques et empiriques relatives à l’étude des déchets de fabrications en os, afin de démontrer la pertinence de considérer ces derniers dans la compréhension des systèmes socioéconomiques et culturels.

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Bien que l’os soit une matière première ayant joué un rôle essentiel au sein des activités quotidiennes des Iroquoiens du Saint-Laurent, il existe à ce jour très peu d’analyses systématiques de l’outillage en os et des débris de fabrication retrouvés en Iroquoianie. Afin de pallier ces lacunes, ce mémoire de maitrise porte sur l’analyse des vestiges en os ouvragés récupérés sur le site villageois Mailhot-Curran (BgFn-2), occupé durant le Sylvicole supérieur tardif par une communauté iroquoienne du Saint-Laurent. Plus précisément, l’étude consiste à analyser l’industrie osseuse en portant une attention particulière aux déchets de fabrication. Cet examen attentif a pour principal objectif de documenter les modes de gestion et de sélection de la matière première ainsi que d’améliorer la compréhension des techniques préhistoriques employées pour la fabrication des objets en os. Au moyen d’analyses technologiques, zooarchéologiques et tracéologiques, il sera possible de classifier les déchets de fabrication, de documenter leur origine technologique et, ultimement, de reconstituer un certain nombre de chaines opératoires. Une étude détaillée de la distribution spatiale des artéfacts permettra également de mieux comprendre l’organisation des activités dans l’espace villageois. Ce mémoire a aussi pour objectif de fournir des balises méthodologiques et empiriques relatives à l’étude des déchets de fabrications en os, afin de démontrer la pertinence de considérer ces derniers dans la compréhension des systèmes socioéconomiques et culturels.

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The occurrence of OsHV-1, a herpes virus causing mass mortality in the Pacific oyster Crassostrea gigas was investigated with the aim to select individuals with different susceptibility to the infection. Naïve spat transferred to infected areas and juveniles currently being grown at those sites were analyzed using molecular and histology approaches. The survey period distinguishes itself by very warm temperatures reaching up to 3.5°C above the average. The virus was not detected in the virus free area although a spread of the disease could be expected due to high temperatures. Overall mortality, prevalence of infection and viral load was higher in spat confirming the higher susceptibility in early life stages. OsHV-1 and oyster mortality were detected in naïve spat after 15 days of cohabitation with infected animals. Although, infection was associated with mortality in spat, the high seawater temperatures could also be the direct cause of mortality at the warmest site. One stock of juveniles suffered an event of abnormal mortality that was significantly associated with OsHV-1 infection. Those animals were infected with a previously undescribed microvariant whereas the other stocks were infected with OsHV-1 μVar. Cell lesions due to the infection were observed by histology and true infections were corroborated by in situ hybridization. Survivors from the natural outbreak were exposed to OsHV-1 μVar by intramuscular injection and were compared to naïve animals. The survival rate in previously exposed animals was significantly higher than in naïve oysters. Results derived from this study allowed the selection of animals that might possess interesting characteristics for future analysis on OsHV-1 resistance.

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Human bocavirus 1 (HBoV1) is associated with respiratory infections worldwide, mainly in children. Similar to other parvoviruses, it is believed that HBoV1 can persist for long periods of time in humans, probably through maintaining concatemers of the virus single-stranded DNA genome in the nuclei of infected cells. Recently, HBoV-1 was detected in high rates in adenoid and palatine tonsils samples from patients with chronic adenotonsillar diseases, but nothing is known about the virus replication levels in those tissues. A 3-year prospective hospital-based study was conducted to detect and quantify HBoV1 DNA and mRNAs in samples of the adenoids (AD), palatine tonsils (PT), nasopharyngeal secretions (NPS), and peripheral blood (PB) from patients undergoing tonsillectomy for tonsillar hypertrophy or recurrent tonsillitis. HBoV1 was detected in 25.3% of the AD samples, while the rates of detection in the PT, NPS, and PB samples were 7.2%, 10.5%, and 1.7%, respectively. The viral loads were higher in AD samples, and 27.3% of the patients with HBoV had mRNA detectable in this tissue. High viral loads and detectable mRNA in the AD were associated with HBoV1 detection in the other sample sites. The adenoids are an important site of HBoV1 replication and persistence in children with tonsillar hypertrophy. The adenoids contain high HBoV1 loads and are frequently positive for HBoV mRNA, and this is associated with the detection of HBoV1 in secretions.

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Despite the remarkable improvements in breast cancer (BC) characterization, accurate prediction of BC clinical behavior is often still difficult to achieve. Some studies have investigated the association between the molecular subtype, namely the basal-like BC and the pattern of relapse, however only few investigated the association between relapse pattern and immunohistochemical defined triple-negative breast cancers (TNBCs). The aim of this study was to evaluate the pattern of relapse in patients with TNBC, namely the primary distant relapse site. One-hundred twenty nine (129) invasive breast carcinomas with follow-up information were classified according to the molecular subtype using immunohistochemistry for ER, PgR and Her2. The association between TNBC and distant relapse primary site was analyzed by logistic regression. Using multivariate logistic regression analysis patients with TNBC displayed only 0.09 (95% CI: 0.00-0.74; p=0.02) the odds of the non-TNBC patients of developing bone primary relapse. Regarding visceral and lymph-node relapse, no differences between in this cohort were found. Though classically regarded as aggressive tumors, TNBCs rarely development primary relapse in bone when compared to non-TNBC, a clinical relevant fact when investigating a metastasis of an occult or non-sampled primary BC.

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Negative-ion mode electrospray ionization, ESI(-), with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was coupled to a Partial Least Squares (PLS) regression and variable selection methods to estimate the total acid number (TAN) of Brazilian crude oil samples. Generally, ESI(-)-FT-ICR mass spectra present a power of resolution of ca. 500,000 and a mass accuracy less than 1 ppm, producing a data matrix containing over 5700 variables per sample. These variables correspond to heteroatom-containing species detected as deprotonated molecules, [M - H](-) ions, which are identified primarily as naphthenic acids, phenols and carbazole analog species. The TAN values for all samples ranged from 0.06 to 3.61 mg of KOH g(-1). To facilitate the spectral interpretation, three methods of variable selection were studied: variable importance in the projection (VIP), interval partial least squares (iPLS) and elimination of uninformative variables (UVE). The UVE method seems to be more appropriate for selecting important variables, reducing the dimension of the variables to 183 and producing a root mean square error of prediction of 0.32 mg of KOH g(-1). By reducing the size of the data, it was possible to relate the selected variables with their corresponding molecular formulas, thus identifying the main chemical species responsible for the TAN values.

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Surgical site infections (SSIs) can affect body tissues, cavities, or organs manipulated in surgery and constitute 14% to 16% of all infections. This study aimed to determine the incidence of SSIs in women following their discharge from a gynecology outpatient clinic, to survey different types of SSIs among women, and to verify the association of SSIs with comorbidities and clinical conditions. Data were collected via analytical observation with a cross-sectional design, and the study was conducted in 1,026 women who underwent gynecological surgery in a teaching hospital in the municipality of Teresina, in the northeast Brazilian State of Piauí, from June 2011 to March 2013. The incidence of SSIs after discharge was 5.8% among the women in the outpatient clinic. The most prevalent surgery among the patients was hysterectomy, while the most prevalent type of SSI was superficial incisional. Comorbidities in women with SSIs included cancer, diabetes mellitus, and hypertension. Surveillance of SSIs during the post-discharge period is critical for infection prevention and control. It is worth reflecting on the planning of surgical procedures for patients who have risk factors for the development of SSIs.

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The role of orbital differentiation on the emergence of superconductivity in the Fe-based superconductors remains an open question to the scientific community. In this investigation, we employ a suitable microscopic spin probe technique, namely Electron Spin Resonance (ESR), to investigate this issue on selected chemically substituted BaFe2As2 single crystals. As the spin-density wave (SDW) phase is suppressed, we observe a clear increase of the Fe 3d bands anisotropy along with their localization at the FeAs plane. Such an increase of the planar orbital content is interestingly independent of the chemical substitution responsible for suppressing the SDW phase. As a consequence, the magnetic fluctuations in combination with this particular symmetry of the Fe 3d bands are propitious ingredients for the emergence of superconductivity in this class of materials.

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The genera Cochliomyia and Chrysomya contain both obligate and saprophagous flies, which allows the comparison of different feeding habits between closely related species. Among the different strategies for comparing these habits is the use of qPCR to investigate the expression levels of candidate genes involved in feeding behavior. To ensure an accurate measure of the levels of gene expression, it is necessary to normalize the amount of the target gene with the amount of a reference gene having a stable expression across the compared species. Since there is no universal gene that can be used as a reference in functional studies, candidate genes for qPCR data normalization were selected and validated in three Calliphoridae (Diptera) species, Cochliomyia hominivorax Coquerel, Cochliomyia macellaria Fabricius, and Chrysomya albiceps Wiedemann . The expression stability of six genes ( Actin, Gapdh, Rp49, Rps17, α -tubulin, and GstD1) was evaluated among species within the same life stage and between life stages within each species. The expression levels of Actin, Gapdh, and Rp49 were the most stable among the selected genes. These genes can be used as reliable reference genes for functional studies in Calliphoridae using similar experimental settings.

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We compared the indication of laparoscopy for treatment of adnexal masses based on the risk scores and tumor diameters with the indication based on gynecology-oncologists' experience. This was a prospective study of 174 women who underwent surgery for adnexal tumors (116 laparotomies, 58 laparoscopies). The surgeries begun and completed by laparoscopy, with benign pathologic diagnosis, were considered successful. Laparoscopic surgeries that required conversion to laparotomy, led to a malignant diagnosis, or facilitated cyst rupture were considered failures. Two groups were defined for laparoscopy indication: (1) absence of American College of Obstetrics and Gynecology (ACOG) guideline for referral of high-risk adnexal masses criteria (ACOG negative) associated with 3 different tumor sizes (10, 12, and 14 cm); and (2) Index of Risk of Malignancy (IRM) with cutoffs at 100, 200, and 300, associated with the same 3 tumor sizes. Both groups were compared with the indication based on the surgeon's experience to verify whether the selection based on strict rules would improve the rate of successful laparoscopy. ACOG-negative and tumors ≤10 cm and IRM with a cutoff at 300 points and tumors ≤10cm resulted in the same best performance (78% success = 38/49 laparoscopies). However, compared with the results of the gynecology-oncologists' experience, those were not statistically significant. The selection of patients with adnexal mass to laparoscopy by the use of the ACOG guideline or IRM associated with tumor diameter had similar performance as the experience of gynecology-oncologists. Both methods are reproducible and easy to apply to all women with adnexal masses and could be used by general gynecologists to select women for laparoscopic surgery; however, referral to a gynecology-oncologist is advisable when there is any doubt.

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studies have shown that rate of propofol infusion may influence the predicted propofol concentration at the effect site (Es). The aim of this study was to evaluate the Es predicted by the Marsh pharmacokinetic model (ke0 0.26min(-1)) in loss of consciousness during fast or slow induction. the study included 28 patients randomly divided into two equal groups. In slow induction group (S), target-controlled infusion (TCI) of propofol with plasma, Marsh pharmacokinetic model (ke0 0.26min(-1)) with target concentration (Tc) at 2.0-μg.mL(-1) were administered. When the predicted propofol concentration at the effect site (Es) reached half of Es value, Es was increased to previous Es + 1μg.mL(-1), successively, until loss of consciousness. In rapid induction group (R), patients were induced with TCI of propofol with plasma (6.0μg.ml(-1)) at Es, and waited until loss of consciousness. in rapid induction group, Tc for loss of consciousness was significantly lower compared to slow induction group (1.67±0.76 and 2.50±0.56μg.mL(-1), respectively, p=0.004). the predicted propofol concentration at the effect site for loss of consciousness is different for rapid induction and slow induction, even with the same pharmacokinetic model of propofol and the same balance constant between plasma and effect site.

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Universidade Estadual de Campinas . Faculdade de Educação Física