977 resultados para 63, 22 p.


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2015

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Projeto de ³s-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária

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Knowledge sharing typically examines organizational transfer of knowledge, often from headquarters to subsidiaries, from developed country sites to emerging country sites, or from host to local employees. Yes, recent research, such as Prahaladâs Bottom of the Pyramid, raises the question of reverse transfer of knowledge, or whether knowledge could and should be transferred from local sites to home country sites within an organization. As several emerging economies build their capabilities in knowledge, research and development, marketing, and the like, it only makes sense to consider what type of knowledge and how to transfer it in reverse or bi-directional manners. This paper takes one step back in the process. Rather than focusing on what knowledge transfer may make sense within an organization, we consider what types of knowledge are important for foreigners to know at the initial stages of engagement abroad as they consider whether to do business in an emerging country.

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BACKGROUND: Lumbar disc herniation has a prevalence of up to 58% in the athletic population. Lumbar discectomy is a common surgical procedure to alleviate pain and disability in athletes. We systematically reviewed the current clinical evidence regarding athlete return to sport (RTS) following lumbar discectomy compared to conservative treatment. METHODS: A computer-assisted literature search of MEDLINE, CINAHL, Web of Science, PEDro, OVID and PubMed databases (from inception to August 2015) was utilised using keywords related to lumbar disc herniation and surgery. The design of this systematic review was developed using the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Methodological quality of individual studies was assessed using the Downs and Black scale (0-16 points). RESULTS: The search strategy revealed 14 articles. Downs and Black quality scores were generally low with no articles in this review earning a high-quality rating, only 5 articles earning a moderate quality rating and 9 of the 14 articles earning a low-quality rating. The pooled RTS for surgical intervention of all included studies was 81% (95% CI 76% to 86%) with significant heterogeneity (I(2)=63.4%, p<0.001) although pooled estimates report only 59% RTS at same level. Pooled analysis showed no difference in RTS rate between surgical (84% (95% CI 77% to 90%)) and conservative intervention (76% (95% CI 56% to 92%); p=0.33). CONCLUSIONS: Studies comparing surgical versus conservative treatment found no significant difference between groups regarding RTS. Not all athletes that RTS return at the level of participation they performed at prior to surgery. Owing to the heterogeneity and low methodological quality of included studies, rates of RTS cannot be accurately determined.

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While much research has focused on entrepreneurship and creativity in developed economies, the notions of both topics are still embryonic in many emerging economies. This paper focuses on entrepreneurs in one such economy, Vietnam, to understand the perceptions of entrepreneurs about the role that innovation and creativity may play in their own entrepreneurial ventures and success. This is important because before reaping benefits from entrepreneurship, entrepreneurs need to decide when and on what conditions they start based on their calculations of required resources and predictions of likely outcomes. The research also sought to understand how "creativity," broadly applied ("innovation" and "creative performance") affects the ways that entrepreneurs think about and anticipate their own success and decisions. In essence, the study suggests that the higher the entrepreurâs creativity is, the more likely she or he is to start a new business and believe success will result. Future research could examine whether history, industry and geographic location matter in entrepreneursâ perceptions as well as whether transition/emerging economies like Vietnam may have different views altogether about the two key concepts.

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Objective: The purpose of the study was to examine the relationship of surveillance and control activities in Canadian hospitals with rates of nosocomial methicillin-resistant S. aureus (MRSA), C. difficile associated diarrhea (CDAD), and vancomycin-resistant Enterococcus (VRE). Methods: Surveys were sent to Infection Control programs in hospitals that participated in an earlier survey of infection control practices in Canadian acute care hospitals. Results: One hundred and twenty of 145 (82.8%) hospitals responded to the survey. The mean MRSA rate was 2.0 (SD 2.9) per 1,000 admissions, the mean CDAD rate was 3.8 (SD 4.3), and the mean VRE rate was 0.4 (SD 1.5). Multiple stepwise regression analysis found hospitals that reported infection rates by specific risk groups (r = - 0.27, p < 0.01) and that kept attendance records of infection control teaching activities (r = - 0.23, p < 0.01) were associated with lower MRSA rates. Multiple stepwise regression analysis found larger hospitals (r = 0.25, p < 0.01) and hospitals where infection control committees or staff had the direct authority to close a ward or unit to further admissions due to outbreaks (r = 0.22, p < 0.05) were associated with higher CDAD rates. Multiple logistic regression analysis found larger hospitals (OR = 1.6, CI 1.2 - 2.0, p = 0.003) and teaching hospitals (OR = 3.7, CI 1.2 - 11.8, p = 0.02) were associated with the presence of VRE. Hospitals were less likely to have VRE when infection control staff frequently contacted physicians and nurses for reports of new infections (OR = 0.5, CI 0.3 - 0.7, p = 0.02) and there were in-service programs for updating nursing and ancillary staff on current infection control practices (OR = 0.2, CI 0.1 - 0.7, p = 0.01). Conclusions: Surveillance and control activities were associated with MRSA and CDAD rates and the presence of VRE. Surveillance and control activities might be especially beneficial in large and teaching hospitals.

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<p>Isotope shifts in dielectronic recombination spectra were studied for Li-like <sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);"><em>A</em></sup>Nd<sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);">57+</sup> ions with <em>A</em>=142 and <em>A</em>=150. From the displacement of resonance positions energy shifts <em>d</em><em>E</em><sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);">142?150</sup>(2<em>s</em>-2<em>p</em><sub style="margin: 0px; padding: 0px; border: 0px; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; line-height: 18px; text-align: justify; background-color: rgb(255, 255, 255);">1/2</sub>)=40.2(3)(6)??meV [(stat)(sys)] and <em>d</em><em>E</em><sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);">142?150</sup>(2<em>s</em>-2<em>p</em><sub style="margin: 0px; padding: 0px; border: 0px; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; line-height: 18px; text-align: justify; background-color: rgb(255, 255, 255);">3/2</sub>)=42.3(12)(20)??meV of 2<em>s</em>-2<em>p</em><sub style="margin: 0px; padding: 0px; border: 0px; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; line-height: 18px; text-align: justify; background-color: rgb(255, 255, 255);"><em>j</em></sub>transitions were deduced. An evaluation of these values within a full QED treatment yields a change in the mean-square charge radius of <sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);">142?150</sup><em>d</em>?<em>r</em><sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);">2</sup>?=-1.36(1)(3)??fm<sup style="margin: 0px; padding: 0px; border: 0px; font-size: 0.88em; vertical-align: 0.5em; line-height: 1em; color: rgb(50, 50, 50); font-family: arial, helvetica, sans-serif; text-align: justify; background-color: rgb(255, 255, 255);">2</sup>. The approach is conceptually new and combines the advantage of a simple atomic structure with high sensitivity to nuclear size.</p>

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Objectives:<br/>We studied whether an increase in adenosine dose overcomes caffeine antagonism on adenosine-mediated coronary vasodilation.<br/><br/>Background:<br/>Caffeine is a competitive antagonist at the adenosine receptors, but it is unclear whether caffeine in coffee alters the actions of exogenous adenosine, and whether the antagonism can be surmounted by increasing the adenosine dose.<br/><br/>Methods:<br/>Myocardial perfusion scintigraphy (MPS) was used to assess adenosine-induced hyperemia in 30 patients before (baseline) and after coffee ingestion (caffeine). At baseline, patients received 140 µg/kg/min of adenosine combined with low-level exercise. For the caffeine study, 12 patients received 140 µg/kg/min of adenosine (standard) and 18 patients received 210 µg/kg/min (high dose) after caffeine intake (200 mg). Myocardial perfusion was assessed semiquantitatively and quantitatively, and perfusion defect was characterized according to the presence of reversibility.<br/><br/>Results:<br/>Caffeine reduced the magnitude of perfusion abnormality induced by standard adenosine as measured by the summed difference score (SDS) (12.0 ± 4.4 at baseline vs. 4.1 ± 2.1 after caffeine, p &lt; 0.001) as well as defect size (18% [3% to 38%] vs. 8% [0% to 22%], p &lt; 0.01), whereas it had no effect on the abnormalities caused by high-dose adenosine (SDS, 7.7 ± 4.0 at baseline vs. 7.8 ± 4.2 after caffeine, p = 0.7). There was good agreement between baseline and caffeine studies for segmental defect category (kappa = 0.72, 95% confidence interval: 0.65 to 0.79) in the high-dose group. An increase in adenosine after caffeine intake was well tolerated.<br/><br/>Conclusions:<br/>Caffeine in coffee attenuates adenosine-induced coronary hyperemia and, consequently, the detection of perfusion abnormality by adenosine MPS. This can be overcome by increasing the adenosine dose without compromising test tolerability.

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Background: Dietary patterns, which represent whole-diet and possible food and nutrient interactions, have been linked to the risk of various cancers. However, the associations of these dietary patterns with breast cancer remain unclear. Objective: We critically appraised the literature and conducted meta-analyses to pool the results of studies to clarify the relation between dietary patterns and breast cancer risk. <br/>Design: MEDLINE and EMBASE were searched for relevant articles that identified common dietary patterns published up to November 2009. Multivariable-adjusted odds ratios (ORs) comparing highest and lowest categories of dietary pattern scores and multi-variable-adjusted ORs for a 20th-percentile increase in dietary pattern scores were combined by using random-effects meta-analyses. Results: Case-control and cohort studies were retrieved that identified prudent/healthy (n = 18), Western/unhealthy (n = 17), and drinker (n = 4) dietary patterns. There was evidence of a decrease in the risk of breast cancer in the highest compared with the lowest categories of prudent/healthy dietary patterns (OR = 0.89; 95% CI: 0.82, 0.99; P = 0.02) in all studies and in pooled cohort studies alone. An increase in the risk of breast cancer was shown for the highest compared with the lowest categories of a drinker dietary pattern (OR = 1.21; 95% CI: 1.04, 1.41; P = 0.01). There was no evidence of a difference in the risk of breast cancer between the highest and the lowest categories of Western/unhealthy dietary patterns (OR = 1.09; 95% CI: 0.98, 1.22; P = 0.12). Conclusion: The results of this systematic review and meta-analysis indicate that some dietary patterns may be associated with breast cancer risk.

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Critically ill patients are at heightened risk for nosocomial infections. The anaphylatoxin C5a impairs phagocytosis by neutrophils. However, the mechanisms by which this occurs and the relevance for acquisition of nosocomial infection remain undetermined. We aimed to characterize mechanisms by which C5a inhibits phagocytosis in vitro and in critically ill patients, and to define the relationship between C5a-mediated dysfunction and acquisition of nosocomial infection. In healthy human neutrophils, C5a significantly inhibited RhoA activation, preventing actin polymerization and phagocytosis. RhoA inhibition was mediated by PI3Kd. The effects on RhoA, actin, and phagocytosis were fully reversed by GM-CSF. Parallel observations were made in neutrophils from critically ill patients, that is, impaired phagocytosis was associated with inhibition of RhoA and actin polymerization, and reversed by GM-CSF. Among a cohort of 60 critically ill patients, C5a-mediated neutrophil dysfunction (as determined by reduced CD88 expression) was a strong predictor for subsequent acquisition of nosocomial infection (relative risk, 5.8; 95% confidence interval, 1.5-22; P = .0007), and remained independent of time effects as assessed by survival analysis (hazard ratio, 5.0; 95% confidence interval, 1.3-8.3; P = .01). In conclusion, this study provides new insight into the mechanisms underlying immunocompromise in critical illness and suggests novel avenues for therapy and prevention of nosocomial infection.

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The aim of the present study was to compare the effect of lutein- and zeaxanthin-rich foods and supplements on macular pigment level (MPL) and serological markers of endothelial activation, inflammation and oxidation in healthy volunteers. We conducted two 8-week intervention studies. Study 1 (n 52) subjects were randomised to receive either carrot juice (a carotene-rich food) or spinach powder (a lutein- and zeaxanthin-rich food) for 8 weeks. Study 2 subjects (n 75) received supplements containing lutein and zeaxanthin, ß-carotene, or placebo for 8 weeks in a randomised, double-blind, placebo-controlled trial. MPL, serum concentrations of lipid-soluble antioxidants, inter-cellular adhesion molecule 1, vascular cell adhesion molecule 1, C-reactive protein and F2-isoprostane levels were assessed at baseline and post-intervention in both studies. In these intervention studies, no effects on MPL or markers of endothelial activation, inflammation or oxidation were observed. However, the change in serum lutein and zeaxanthin was associated or tended to be associated with the change in MPL in those receiving lutein- and zeaxanthin-rich foods (lutein r 0.40, P = 0.05; zeaxanthin r 0.30, P = 0.14) or the lutein and zeaxanthin supplement (lutein r 0.43, P = 0.03; zeaxanthin r 0.22, P = 0.28). In both studies, the change in MPL was associated with baseline MPL (food study r - 0.54, P &lt;0.001; supplement study r - 0.40, P &lt;0.001). We conclude that this 8-week supplementation with lutein and zeaxanthin, whether as foods or as supplements, had no significant effect on MPL or serological markers of endothelial activation, inflammation and oxidation in healthy volunteers, but may improve MPL in the highest serum responders and in those with initially low MPL.

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<p>The composition of a dynamic mixture of similar 2,2'-bipyridine complexes of iron(II) bearing either an amide (5-benzylamido-2,2'-bipyridine and 5-(2-methoxyethane)amido-2,2'-bipyridine) or an ester (2,2'-bipyridine-5-carboxylic acid benzylester and 2,2'-bipyridine-5-carboxylic acid 2-methoxyethane ester) side chain have been evaluated by electrospray mass spectroscopy in acetonitrile. The time taken for the complexes to come to equilibrium appears to be dependent on the counteranion, with chloride causing a rapid redistribution of two preformed heteroleptic complexes (of the order of 1 hour), whereas the time it takes in the presence of tetrafluoroborate salts is in excess of 24^^h. Similarly the final distribution of products is dependent on the anion present, with the presence of chloride, and to a lesser extent bromide, preferring three amide-functionalized ligands, and a slight preference for an appended benzyl over a methoxyethyl group. Furthermore, for the first time, this study shows that the distribution of a dynamic library of metal complexes monitored by ESI-MS can adapt following the introduction of a different anion, in this case tetrabutylammonium chloride to give the most favoured heteroleptic complex despite the increasing ionic strength of the solution. </p>

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<p>Peatlands are a key component of the global carbon cycle. Chronologies of peatland initiation are typically based on compiled basal peat radiocarbon (14C) dates and frequency histograms of binned calibrated age ranges. However, such compilations are problematic because poor quality 14C dates are commonly included and because frequency histograms of binned age ranges introduce chronological artefacts that bias the record of peatland initiation. Using a published compilation of 274 basal 14C dates from Alaska as a case study, we show that nearly half the 14C dates are inappropriate for reconstructing peatland initiation, and that the temporal structure of peatland initiation is sensitive to sampling biases and treatment of calibrated14C dates. We present revised chronologies of peatland initiation for Alaska and the circumpolar Arctic based on summed probability distributions of calibrated 14C dates. These revised chronologies reveal that northern peatland initiation lagged abrupt increases in atmospheric CH4 concentration at the start of the BøllingâAllerød interstadial (Termination 1A) and the end of the Younger Dryas chronozone (Termination 1B), suggesting that northern peatlands were not the primary drivers of the rapid increases in atmospheric CH4. Our results demonstrate that subtle methodological changes in the synthesis of basal 14C ages lead to substantially different interpretations of temporal trends in peatland initiation, with direct implications for the role of peatlands in the global carbon cycle.</p>

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<p>The standard local density approximation and generalized gradient approximations fail to properly describe the dissociation of an electron pair bond, yielding large errors (on the order of 50 kcal/mol) at long bond distances. To remedy this failure, a self-consistent Kohn-Sham (KS) method is proposed with the exchange-correlation (xc) energy and potential depending on both occupied and virtual KS orbitals. The xc energy functional of Buijse and Baerends [Mol. Phys. 100, 401 (2002); Phys. Rev. Lett. 87, 133004 (2001)] is employed, which, based on an ansatz for the xc-hole amplitude, is able to reproduce the important dynamical and nondynamical effects of Coulomb correlation through the efficient use of virtual orbitals. Self-consistent calculations require the corresponding xc potential to be obtained, to which end the optimized effective potential (OEP) method is used within the common energy denominator approximation for the static orbital Green's function. The problem of the asymptotic divergence of the xc potential of the OEP when a finite number of virtual orbitals is used is addressed. The self-consistent calculations reproduce very well the entire H-2 potential curve, describing correctly the gradual buildup of strong left-right correlation in stretched H-2. (C) 2003 American Institute of Physics.</p>