941 resultados para Leslie, George, d. 1637.


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La esclerosis sistémica (ES) es una enfermedad autoinmune multisistémica que afecta principalmente la piel, los pulmones, el tracto gastrointestinal, el corazón y los riñones. La enfermedad pulmonar, presente en casi el 100% de los casos, es el factor con mayor influencia en la mortalidad. El propósito de este estudio es realizar un análisis detallado de la enfermedad pulmonar por tomografía computarizada de alta resolución(TCAR) en pacientes Colombianos con ES, para lo cual se realizó un estudio de prevalencia analítica en 44 pacientes con ES valorados en el Hospital Universitario Mayor Méderi en los últimos 7 años. Los resultados mostraron características demográficas y clínicas similares a las previamente descritas. La prevalencia de enfermedad pulmonar intersticial fue alta, y los hallazgos de fibrosis pulmonar como vidrio esmerilado y panal de abejas se asociaron con la presencia del autoanticuerpo antiSCL70. La medida del diámetro esofágico por TCAR fue mayor en los pacientes con disfagia, antiSCL 70 y linfopenia, los cuales son marcadores de mal pronóstico.

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1. Litter decomposition recycles nutrients and causes large fluxes of carbon dioxide into the atmosphere. It is typically assumed that climate, litter quality and decomposer communities determine litter decay rates, yet few comparative studies have examined their relative contributions in tropical forests. 2. We used a short-term litterbag experiment to quantify the effects of litter quality, placement and mesofaunal exclusion on decomposition in 23 tropical forests in 14 countries. Annual precipitation varied among sites (760-5797 mm). At each site, two standard substrates (Raphia farinifera and Laurus nobilis) were decomposed in fine- and coarse-mesh litterbags both above and below ground for approximately 1 year. 3. Decomposition was rapid, with >95% mass loss within a year at most sites. Litter quality, placement and mesofaunal exclusion all independently affected decomposition, but the magnitude depended upon site. Both the average decomposition rate at each site and the ratio of above- to below-ground decay increased linearly with annual precipitation, explaining 60-65% of among-site variation. Excluding mesofauna had the largest impact on decomposition, reducing decomposition rates by half on average, but the magnitude of decrease was largely independent of climate. This suggests that the decomposer community might play an important role in explaining patterns of decomposition among sites. Which litter type decomposed fastest varied by site, but was not related to climate. 4. Synthesis. A key goal of ecology is to identify general patterns across ecological communities, as well as relevant site-specific details to understand local dynamics. Our pan-tropical study shows that certain aspects of decomposition, including average decomposition rates and the ratio of above- to below-ground decomposition are highly correlated with a simple climatic index: mean annual precipitation. However, we found no relationship between precipitation and effects of mesofaunal exclusion or litter type, suggesting that site-specific details may also be required to understand how these factors affect decomposition at local scales.

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The evolution of eusociality is one of the major transitions in evolution, but the underlying genomic changes are unknown. We compared the genomes of 10 bee species that vary in social complexity, representing multiple independent transitions in social evolution, and report three major findings. First, many important genes show evidence of neutral evolution as a consequence of relaxed selection with increasing social complexity. Second, there is no single road map to eusociality; independent evolutionary transitions in sociality have independent genetic underpinnings. Third, though clearly independent in detail, these transitions do have similar general features, including an increase in constrained protein evolution accompanied by increases in the potential for gene regulation and decreases in diversity and abundance of transposable elements. Eusociality may arise through different mechanisms each time, but would likely always involve an increase in the complexity of gene networks.

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The structures and association properties of thermosensitive block copolymers of poly(methoxyoligo( ethylene glycol) norbornenyl esters) in D2O were investigated by small angle neutron scattering (SANS). Each block is a comblike polymer with a polynorbornene (PNB) backbone and oligo ethylene glycol (OEG) side chains (one side chain per NB repeat unit). The chemical formula of the block copolymer is (OEG3NB) 79- (OEG6.6NB) 67, where subscripts represent the degree of polymerization (DP) of OEG and NB in each block. The polymer concentration was fixed at 2.0 wt % and the structural changes were investigated over a temperature range between 25 and 68°C. It was found that at room temperature polymers associate to form micelles with a spherical core formed by the block (OEG3NB) 79 and corona formed by the block (OEG6.6NB) 67 and that the shape of the polymer in the corona could be described by the form factor of rigid cylinders. At elevated temperatures, the aggregation number increased and the micelles became more compact. At temperatures around the cloud point temperature (CPT) T ) 60 °C a correlation peak started to appear and became pronounced at 68 °C due to the formation of a partially ordered structure with a correlation length ∼349 Å.

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It is thought that speciation in phytophagous insects is often due to colonization of novel host plants, because radiations of plant and insect lineages are typically asynchronous. Recent phylogenetic comparisons have supported this model of diversification for both insect herbivores and specialized pollinators. An exceptional case where contemporaneous plant-insect diversification might be expected is the obligate mutualism between fig trees (Ficus species, Moraceae) and their pollinating wasps (Agaonidae, Hymenoptera). The ubiquity and ecological significance of this mutualism in tropical and subtropical ecosystems has long intrigued biologists, but the systematic challenge posed by >750 interacting species pairs has hindered progress toward understanding its evolutionary history. In particular, taxon sampling and analytical tools have been insufficient for large-scale cophylogenetic analyses. Here, we sampled nearly 200 interacting pairs of fig and wasp species from across the globe. Two supermatrices were assembled: on an average, wasps had sequences from 77% of 6 genes (5.6 kb), figs had sequences from 60% of 5 genes (5.5 kb), and overall 850 new DNA sequences were generated for this study. We also developed a new analytical tool, Jane 2, for event-based phylogenetic reconciliation analysis of very large data sets. Separate Bayesian phylogenetic analyses for figs and fig wasps under relaxed molecular clock assumptions indicate Cretaceous diversification of crown groups and contemporaneous divergence for nearly half of all fig and pollinator lineages. Event-based cophylogenetic analyses further support the codiversification hypothesis. Biogeographic analyses indicate that the present-day distribution of fig and pollinator lineages is consistent with a Eurasian origin and subsequent dispersal, rather than with Gondwanan vicariance. Overall, our findings indicate that the fig-pollinator mutualism represents an extreme case among plant-insect interactions of coordinated dispersal and long-term codiversification.

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La tesi affronta la vita e la riflessione politica di Beatrice Potter collocandola all’interno del pensiero politico britannico ed europeo della fine dell’Ottocento e dei primi decenni del Novecento. Rispetto alla maggior parte della bibliografia disponibile, risulta un’autonomia e un’originalità anche rispetto alla riflessione del marito Sidney Webb. La riflessione politica di Potter è caratterizzata in primo luogo dalla ricerca del significato immediatamente politico di quella scienza sociale, che si sta affermando come approccio scientifico dominante nell’intero panorama europeo. Il lavoro è diviso in tre ampi capitoli così suddivisi: il primo ricostruisce l’eredità intellettuale di Potter, con particolare attenzione al rapporto con la filosofia evoluzionista di Herbert Spencer, suo mentore e amico. In questo capitolo vengono anche discussi i contributi di John Stuart Mill, Joseph Chamberlain, Alfred Marshall e Karl Marx e la loro influenza sull’opera di Potter. Il secondo capitolo prende in esame la sua opera prima dell’incontro con il marito e mostra come lo studio della povertà, del lavoro, della metropoli, della cooperazione e delle condizioni delle donne getti le basi di tutta la produzione successiva della partnership. Lo studio politico della povertà, cioè la messa a punto di una scienza amministrativa del carattere sociale del lavoro, rappresenta uno degli elementi principali di quella che viene qui definita un’epistemologia della democrazia. Il terzo capitolo riprende il tema cruciale della democrazia nella sua accezione «industriale» e indaga il ruolo funzionale dello Stato, anche in relazione alla teoria pluralista di Harold Laski, al socialismo guildista di George D. H. Cole e all’idealismo di Bernard Bosanquet. Centrale in questo confronto del pensiero di Potter con il più ampio dibattito degli anni venti e trenta sulla sovranità è la concezione della decadenza della civiltà capitalista e dell’emergere di una new civilisation, dopo la conversione al comunismo sovietico.

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Background/Aims: To evaluate the alterations of mean foveal thickness (MFT) and visual acuity (VA) outcomes after uncomplicated cataract surgery in different groups of patients. Methods: This study included eyes of consecutive patients who underwent cataract surgery between November 2007 and June 2009. The patients included in the study were divided into 4 groups, as follows: history-free patients, patients with diabetes mellitus without macular involvement at baseline, patients with glaucoma, and patients with epiretinal membrane (ERM). Preoperatively and at 1, 3 and 6 months postoperatively, patients were evaluated for MFT by optical coherence tomography at the central 1-mm macular zone and for logarithm of the minimum angle of resolution best spectacle-corrected VA (BSCVA). Results: A total of 202 eyes were included in the study. MFT values demonstrated a statistically significant increase (p < 0.01) after cataract surgery in all groups at the first and third postoperative month. The history-free (p = 0.09) and glaucoma (p = 0.19) groups did not demonstrate a statistically significant difference in MFT values between the preoperative and 6-month measurements. MFT values 6 months after cataract surgery in the diabetes and ERM groups remained significantly higher (p < 0.01). Despite these findings, VA increased significantly (p < 0.01) in all groups at all postoperative follow-ups. Conclusions: MFT values increased significantly in all groups at the first and third months after cataract surgery. At 6 months, MFT values returned to preoperative levels in the history-free and glaucoma patients, while they remained significantly higher in the diabetic and ERM patients. Despite these macular alterations, BSCVA improved significantly after cataract surgery in all groups at all postoperative follow-ups.

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Sandstone is probably one of the most important groups of rocks in existence today. The economic importance of so insignifi­cant a thing as a mass of sand grains grows with the true reality of the situation. By increasing our knowledge of grains of sand, or particles of sandstone in all their ram­ifications, it would undoubtedly reflect upon our everyday life by increasing commercial possibilities of an undevel­oped natural resource of Montana.

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In this issue...Fish and Game Commission, Peace Corps, Great Falls Brewery, George D. McDonald, Glee club, Intramural basketball, Sugar Bowl, Metals Bank

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We validate, extend, and empirically and theoretically criticize the cultural dimension of humane orientation of the project GLOBE (Global Leadership and Organizational Behavior Effectiveness Research Program). Theoretically, humane orientation is not just a one-dimensionally positive concept about being caring, altruistic, and kind to others as discussed by Kabasakal and Bodur (2004), but there is also a certain ambivalence to this concept. We suggest differentiating humane orientation toward in-group members from humane orientation toward out-group members. A multicountry construct validation study used student samples from 25 countries that were either high or low in humane orientation (N = 876) and studied their relation to the traditional GLOBE scale and other cultural-level measures (agreeableness, religiosity, authoritarianism, and welfare state score). Findings revealed a strong correlation between humane orientation and agreeableness, welfare state score, and religiosity. Out-group humane orientation proved to be the more relevant subfacet of the original humane orientation construct, suggesting that future research on humane orientation should make use of this measure instead of the vague original scale. The ambivalent character of out-group humane orientation is displayed in its positive correlation to high authoritarianism. Patriotism was used as a control variable for noncritical acceptance of one’s society but did not change the correlations. Our findings are discussed as an example of how rigid expectations and a lack of tolerance for diversity may help explain the ambivalent nature of humane orientation

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OBJECTIVE: To evaluate the incidence of colic and risk factors for colic in equids hospitalized for ocular disease. DESIGN: Retrospective observational study. Animals-337 equids (317 horses, 19 ponies, and 1 donkey) hospitalized for ocular disease. PROCEDURES: Medical records of equids hospitalized for > 24 hours for treatment of ocular disease between January 1997 and December 2008 were reviewed. Information from only the first hospitalization was used for equids that were hospitalized for ocular disease on more than 1 occasion. Information gathered included the signalment, the type of ocular lesion and the treatment administered, and any colic signs recorded during hospitalization as well as the severity, presumptive diagnosis, and treatment of the colic. Statistical analysis was used to identify any risk factors for colic in equids hospitalized for ocular disease. RESULTS: 72 of 337 (21.4%) equids hospitalized for ocular disease had signs of colic during hospitalization. Most equids (59.7% [43/72]) had mild signs of colic, and most (87.5% [63/72]) were treated medically. Ten of 72 (13.9%) equids with colic had a cecal impaction. Risk factors for colic in equids hospitalized for ocular disease were age (0 to 1 year and ≥ 21 years) and an increased duration of hospitalization (≥ 8 days). CONCLUSIONS AND CLINICAL RELEVANCE: There was a high incidence of colic in equids hospitalized with ocular disease in this study. Findings from this study may help identify equids at risk for development of colic and thereby help direct implementation of prophylactic measures.

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The International Society for Clinical Densitometry (ISCD) has developed new official positions for the clinical use of quantitative computed tomography (QCT)-based finite element analysis of the spine and hip. The ISCD task force for QCT reviewed the evidence for clinical applications and presented a report with recommendations at the 2015 ISCD Position Development Conference. Here we discuss the agreed upon ISCD official positions with supporting medical evidence, rationale, controversy, and suggestions for further study. Parts I and III address the clinical use of QCT of the hip, and the clinical feasibility of existing techniques for opportunistic screening of osteoporosis using CT scans obtained for other diagnosis such as colonography was addressed.

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The International Society for Clinical Densitometry (ISCD) has developed new official positions for the clinical use of computed tomography (CT) scans acquired without a calibration phantom, for example, CT scans obtained for other diagnosis such as colonography. This also addresses techniques suggested for opportunistic screening of osteoporosis. The ISCD task force for quantitative CT reviewed the evidence for clinical applications of these new techniques and presented a report with recommendations at the 2015 ISCD Position Development Conference. Here we discuss the agreed upon ISCD official positions with supporting medical evidence, rationale, controversy, and suggestions for further study. Advanced techniques summarized as statistical parameter mapping methods were also reviewed. Their future use is promising but the clinical application is premature. The clinical use of QCT of the hip is addressed in part I and of finite element analysis of the hip and spine in part II.