999 resultados para log P


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Partitioning behavior of PAHs including NAP, FLO, PHE, and PYR was investigated. A plot of experimental K-HA against log K-OW gives a good linear relationship. A somewhat similar slope and intercept it-as obtained for the hair-air system using PCB values from the literature. In comparison to K-VA values from the literature, lower values for K-VA were obtained. This may be attributed from differences in species and degradability across biota groups. K-HLA also exhibits good linear relationships with K-OA and other physical chemical properties such as W The lipid fraction has a strong influence on bioconcentration in hair from the air and water. However, hair treatments, hair length, growth dilution, photodegradation, biodegradation, temperature, seasonal variations, wet and dry depositions could alter the degree of bioconcentration of PAHs in the hair.

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The thermal ecology and structural habitat use of two closely related sympatric lizards, Carlia vivax (de Vis) and Lygisaurus foliorum de Vis, were examined in an open sclerophyll forest in subtropical Australia. Comparable mean body temperatures (T-b) and habitat temperatures (T-hab) at the point of capture were recorded for both species. However, sex- related differences in the thermal variables for C. vivax, with females displaying higher temperatures than males, resulted in some significant differences in T-b and T-hab between the species. Variation in T-b and T-hab within and between species was unrelated to time of capture. The difference in T-hab within C. vivax suggested that females were selecting warmer thermal environments than males. Both C. vivax and L. foliorum used most structural features of their habitat randomly as indicated by a similarity in canopy, shrub, ground, log and litter cover and litter depth between habitat surveys and random surveys. However, C. vivax displayed a preference for ground vegetation (height

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Spermatozoa of most crustacean species are nonmotile and are packed into spermatophores. In Decapoda, spermatophores are highly variable in morphology and can be useful in the solving of taxonomic and systematic questions, especially among the Anomura. In this study, the morphology and morphometry of the spermatophores of the western Atlantic hermit crabs Pagurus brevidactylus and P criniticornis are described. The abdomen of fresh male specimens was dissected to expose the reproductive system and to extract the spermatophores, which were analyzed by stereoscopic, light, and scanning electron microscopy. The vas deferens can be divided macroscopically in three regions, all of them containing spermatophores. Tripartite spermatophores are composed of an elongated cylindrical main ampulla, a triangular accessory ampulla, a narrow cylindrical peduncle, and a round pedestal. Dimensions of the spermatophore components are positively correlated to the size of the crab. Morphological patterns observed in this study resemble those of other pagurid hermit crabs investigated to date. The morphological character distribution confirms classifications based on adult morphology and molecular analysis. J. Morphol. 272:1271-1280, 2011. (C) 2011 Wiley-Liss, Inc.

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Teen Triple P is a multilevel system of intervention that is designed to provide parents with specific strategies to promote the positive development of their teenage children as they make the transition into high school and through puberty. The program is based on a combination of education about the developmental needs of adolescents, skills training to improve communication and problem-solving, plus specific modules to deal with common problems encountered by parents and adolescents that can escalate into major conflict and violence. It is designed to increase the engagement of parents of adolescent and pre-adolescent children by providing them with easy access to evidencebased parenting advice and support. This paper presents data collected as part of a survey of over 1400 students in first year high school at 9 Brisbane schools. The survey instrument was constructed to obtain students' reports about behaviour which is known to be associated with their health and wellbeing, and also on the extent to which their parents promoted or discouraged such behaviour at home, at school, and in their social and recreational activities in the wider community. Selected data from the survey were extracted and presented to parents at a series of parenting seminars held at the schools to promote appropriate parenting of teenagers. The objectives were to provide parents with accurate data about teenagers' behaviour, and about teenagers' reports of how they perceived their parents' behaviour. Normative data on parent and teenager behaviour will be presented from the survey as well as psychometric data relating to the reliability and validity of this new measure. Implications of this strategy for increasing parent engagement in parenting programs that aim to reduce behavioural and emotional problems in adolescents will be discussed.

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The present study aimed to determine the richness, occurrence constancy, reproductive modes. standard of abundance distribution, season of vocalization and to test correlation among climatic variables and activity of vocalization of anurans in a region of the Pampa Biome, Santa Maria, Rio Grande do Sul State. During the period of Novernber/2001 to October/2002 monthly collections were carried out utilizing the `survey at breeding site` method and examination of specimens kept in the Colecao Herpetologica do Setor de Zoologia da Universidade Federal de Santa Maria (ZUFSM). Tire Occurrence of 25 species of anurans was recorded. The anurofauna recorded represents 30% of the species known to Occur in Rio Grande do Sul, and comprises species generally associated with grasslands in this state and neighboring countries. Four reproductive modes were recorded: mode 1 (14 species: 58.3%) mode 11 and 30 (9 species` 37.5%) and mode 24 (1 species; 4.2%). The low diversification of reproductive modes is likely related to the homogeneity of the grassland habitat. Most species were constant or accessory in the Study area and the species abundance distribution patterns fit in the Broken Stick and Log-normal models. characterized by homogeneity of species abundance distribution. Most species showed great plasticity in habitat. but few were plastic in vocalization sites use. There was a weak positive correlation between species richness and precipitation. There was also a weak positive correlation between the abundance of species calling activity and maximum average temperatures. These correlations indicated that, in the study area. the abundance of calling males is more affected by the temperature, and species richness is more affected by precipitation, despite the fact that significantly higher species richness occurs during the hottest period of the year. These results showed that the climatological variables examined were not enough to explain the seasonal occurrence of species, thus the influence of other environmental variables merit to be tested in future studies.

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Substance P (SP) is a neuropeptide that can modulate inflammatory mediator release through activation of NK(1) receptors (NK(1)R). Some studies have also suggested the involvement of SP in lipopolysaccharide (LPS)-induced fever. However, the precise contribution of this neuropeptide to the pathways activated during fever is unknown. In this study we investigated the effect of a selective NK(1)R antagonist, SR140333B, on the febrile response induced by LPS and cytokines. Our results show that the systemic injection of SR140333B did not modify the fever induced by LPS at a dose that is able to reduce protein extravasation induced by SP in the skin. On the other hand, intracerebroventricular administration of 5R140333B significantly reduced the fever induced by peripheral injection of LPS. These data emphasize an important role for SP in the central nervous system during the febrile response to LPS, and are reinforced by the fact that intracerebroventricular injection of SP also induced fever in a dose-dependent manner in captopril-treated rats. Considering that the febrile response can result from the generation of several endogenous pyrogens, among them interleukin (IL)-1 beta and macrophage inflammatory protein-1 alpha (CCL3/MIP-1 alpha), we also examined the effect of SR140333B on the fever induced by these cytokines which act through prostaglandin-dependent and independent mechanisms, respectively. Surprisingly, SR140333B did not modify the febrile response to IL-1 beta or CCL3/MIP-1 alpha. Altogether these data suggest that the central action of SP is essential for LPS-, but not for IL-1 beta- or CCL3/MIP-1 alpha-induced fever. (C) 2011 Elsevier B.V. All rights reserved.

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Objectives: We compared 12-month outcomes, regarding ischemic events, repeat intervention, and ST, between diabetic and nondiabetic patients treated with the Genous (TM) EPC capturing R stent (TM) during routine nonurgent percutaneous coronary intervention (PCI) using data from the multicenter, prospective worldwide e-HEALING registry. Background: Diabetic patients have an increased risk for restenosis and stent thrombosis (ST). Methods: In the 4,996 patient e-HEALING registry, 273 were insulin requiring diabetics (IRD), 963 were non-IRD (NIRD), and 3,703 were nondiabetics. The 12-month primary outcome was target vessel failure (TVF), defined as target vessel-related cardiac death or myocardial infarction (MI) and target vessel revascularization. Secondary outcomes were the composite of cardiac death, MI or target lesion revascularization (TLR), and individual outcomes including ST. Cumulative event rates were estimated with the Kaplan-Meier method and compared with a log-rank test. Results: TVF rates were respectively 13.4% in IRD, 9.0% in NIRD, and 7.9% in nondiabetics (P < 0.01). This was mainly driven by a higher mortality hazard in IRD (P < 0.001) and NIRD (P = 0.07), compared with nondiabetics. TLR rates were comparable in NIRD and nondiabetics, but significantly higher in IRD (P = 0.04). No difference was observed in ST. Conclusion: The 1-year results of the Genous stent in a real-world population of diabetics show higher TVF rates in diabetics compared with nondiabetics, mainly driven by a higher mortality hazard. IRD is associated with a significant higher TLR hazard. Definite or probable ST in all diabetic patients was comparable with nondiabetics. (J Interven Cardiol 2011;24:285-294)

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Background: We tested the hypothesis that the universal application of myocardial scanning with single-photon emission computed tomography (SPECT) would result in better risk stratification in renal transplant candidates (RTC) compared with SPECT being restricted to patients who, in addition to renal disease, had other clinical risk factors. Methods: RTCs (n=363) underwent SPECT and clinical risk stratification according to the American Society of Transplantation (AST) algorithm and were followed up until a major adverse cardiovascular event (MACE) or death. Results: Of the 363 patients, 79 patients (22%) had an abnormal SPECT scan and 270 (74%) were classified as high risk. Both methods correctly identified patients with increased probability of MACE. However, clinical stratification performed better (sensitivity and negative predictive value 99% and 99% vs. 25% and 87%, respectively). High-risk patients with an abnormal SPECT scan had a modest increased risk of events (log-rank = 0.03; hazard ratio [HR] = 1.37; 95% confidence interval [95% CI], 1.02-1.82). Eighty-six patients underwent coronary angiography, and coronary artery disease (CAD) was found in 60%. High-risk patients with CAD had an increased incidence of events (log-rank = 0.008; HR=3.85; 95% CI, 1.46-13.22), but in those with an abnormal SPECT scan, the incidence of events was not influenced by CAD (log-rank = 0.23). Forty-six patients died. Clinical stratification, but not SPECT, correlated with the probability of death (log-rank = 0.02; HR=3.25; 95% CI, 1.31-10.82). Conclusion: SPECT should be restricted to high-risk patients. Moreover, in contrast to SPECT, the AST algorithm was also useful for predicting death by any cause in RTCs and for selecting patients for invasive coronary testing.

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OBJECTIVE- To determine whether obesity increases platelet reactivity and thrombin activity in patients with type 2 diabetes plus stable coronary artery disease. RESEARCH DESIGN AND METHODS- We assessed platelet reactivity and markers of thrombin generation and activity in 193 patients from nine clinical sites of the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D). Blood taken at the time of enrollment was used for assay of the concentration of prothrombin fragment 1.2 (PT1.2, released when prothrombin is activated) and fibrinopeptide A (FPA, released when fibrinogen is cleaved). Platelet activation was identified with the use of flow cytometry in response to 0, 0.2, and 1 mu mol/l adenosine diphosphate (ADP). RESULTS- Concentrations of FPA, PT1.2, and platelet activation in the absence of agonist were low. Greater BMI was associated with higher platelet reactivity in response to 1 mu m ADP as assessed by surface expression of P-selectin (r = 0.29, P < 0.0001) but not reflected by the binding of fibrinogen to activated glycoprotein IIb-IIIa. BMI was not associated with concentrations of FPA or PT1.2. Platelet reactivity correlated negatively with A1C (P < 0.04), was not related to the concentration Of triglycerides in blood, and did not correlate with the concentration of C-reactive peptide. CONCLUSIONS- Among patients enrolled in this substudy of BARI 2D, a greater BMI was associated with higher platelet reactivity at the time of enrollment. Our results suggest that obesity and insulin resistance that accompanies obesity may influence platelet reactivity in patients with type 2 diabetes.

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We theoretically study the Hilbert space structure of two neighboring P-donor electrons in silicon-based quantum computer architectures. To use electron spins as qubits, a crucial condition is the isolation of the electron spins from their environment, including the electronic orbital degrees of freedom. We provide detailed electronic structure calculations of both the single donor electron wave function and the two-electron pair wave function. We adopted a molecular orbital method for the two-electron problem, forming a basis with the calculated single donor electron orbitals. Our two-electron basis contains many singlet and triplet orbital excited states, in addition to the two simple ground state singlet and triplet orbitals usually used in the Heitler-London approximation to describe the two-electron donor pair wave function. We determined the excitation spectrum of the two-donor system, and study its dependence on strain, lattice position, and interdonor separation. This allows us to determine how isolated the ground state singlet and triplet orbitals are from the rest of the excited state Hilbert space. In addition to calculating the energy spectrum, we are also able to evaluate the exchange coupling between the two donor electrons, and the double occupancy probability that both electrons will reside on the same P donor. These two quantities are very important for logical operations in solid-state quantum computing devices, as a large exchange coupling achieves faster gating times, while the magnitude of the double occupancy probability can affect the error rate.

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Background: Prolonged use of lamivudine in patients coinfected with HIV and hepatitis B virus (HBV) leads to an increasing risk of lamivudine resistance in both diseases. We investigated the addition of entecavir, a potent inhibitor of HBV polymerase, to lamivudine-containing highly active antiretroviral therapy (HAART) in patients who experienced rebound in HBV viremia while maintaining Suppression of plasma HIV RNA less than 400 copies/ml. Methods: Sixty-eight patients were randomized to entecavir 1 mg (n = 51) or placebo (n = 17) once daily for 24 weeks; 65 patients continued the study with entecavir for an additional 24 weeks. Lamivudine-containing HAART was continued throughout. Results: At week 24, the mean HBV DNA in entecavir-treated patients was 5.52 log(10) - copies/ml versus 9.27 log(10) copies/ml for placebo, and at week 48, it was 4.79log(10) copies/ml versus 5.63log(10) copies/ml, respectively. The mean HBV DNA change from baseline for entecavir was -3.65 log(10) copies/ml (versus + 0.11 for placebo, P < 0.0001) and alanine aminotransferase normalization in 34%. of patients (versus 8% for placebo, P=0.08)At 48 weeks, mean change in HBV DNA reached -4.20log(10) copies/ml inpatients who received entecavir for the entire 48 weeks. The frequency of adverse events with entecavir and placebo was comparable. Through 48 weeks, no clinically relevant changes in HIV viremia or CD4 cell Counts were identified. Conclusion: In this study, entecavir was associated with rapid, clinically significant reductions in HBV DNA, with maintenance of HIV viremia suppression, in HIV/HBV coinfected patients with HBV viremia while on lamivudine treatment. (C) 2008 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.