3,277 research outputs found
Oral anticoagulation in elderly patients as secondary prevention of cardioembolic strokes
<p>Abstract</p> <p>Background</p> <p>Stroke incidence increases with age. Atrial fibrillation (AF) is an important risk factor for ischemic stroke and its incidence also increases with age. However oral anticoagulant therapy (OAT) tends to be underused in the elderly population.</p> <p>Methods</p> <p>Elderly patients (> = 80 years) with an ischemic stroke admitted in our department between 1/7/2003 and 31/6/2005 were prospectively evaluated. Baseline characteristics, risk factors, treatment and etiology according to TOAST criteria were recorded. Patients treated with OAT were followed up in order to assess any side effect and stroke recurrence. Mean follow-up was of 19.5 months (7-45) from discharge.</p> <p>Results</p> <p>Sixty four out of a hundred and fifty nine elderly patients (40.25%) were classified as cardioembolic; mean age was 84.5 years (80-97) and 64.6% were women. AF had been previously identified in 60% of them (16.9% were on OAT and 40.6% on antiplatelet therapy). At discharge, 32 patients (49.2%) were on OAT. In the follow-up 4 patients (12.5%) suffered systemic haemorrhages (3 urinary, 1 gastrointestinal bleeding), with no change in their functional status. Mean INR in this group was 5.9 <abbrgrp><abbr bid="B3">3</abbr><abbr bid="B4">4</abbr><abbr bid="B5">5</abbr><abbr bid="B6">6</abbr><abbr bid="B7">7</abbr><abbr bid="B8">8</abbr><abbr bid="B9">9</abbr><abbr bid="B10">10</abbr><abbr bid="B11">11</abbr></abbrgrp> and, in 3 of them, OAT was cancelled. No brain haemorrhages were recorded. Ischemic stroke recurred in 4 patients (INR < 1.8 in 3 of them; the other, INR 2.35). Three patients had died at the end of the follow-up, one of them as a consequence of ischemic stroke recurrence.</p> <p>Discussion</p> <p>Twenty eight point eight of stroke patients admitted in the period of study were >80 years. The high proportion of cardioembolic strokes in this age segment contrasts with the general underuse of OAT as antithrombotic prophylaxis. Our study suggests that OAT is a safe strategy when carefully prescribed, even for elderly patients.</p
Termorregulación de dos poblaciones de lagartijas simpátridas: Sceloporus lineolateralis y Sceloporus poinsettii (Squamata: Phrynosomatidae) en Durango, México
ResumenLa temperatura ambiental es un factor importante en la regulación de la actividad y los procesos fisiológicos de los organismos ectotermos. Las especies que habitan en simpatría están expuestas a un nicho térmico similar y aquellas especies que están cercanamente emparentadas pueden presentar requerimientos térmicos similares. En el presente trabajo, se estudió la ecología térmica de 2 poblaciones de lagartijas vivíparas, Sceloporus lineolateralis y S. poinsettii, pertenecientes a los grupos Sceloporus torquatus y Sceloporus poinsettii, las cuales habitan en simpatría en la localidad de Peñón Blanco, Durango, México. Las temperaturas corporales de las lagartijas activas en campo y el intervalo de temperaturas corporales preferidas fueron similares entre ambas especies; sin embargo, S. poinsettii registró mayor eficiencia y precisión en la termorregulación, debido a que el intervalo de temperaturas preferidas de esta especie es más amplio. Finalmente, las preferencias térmicas fueron análogas a las registradas anteriormente para los grupos S. torquatus, S. poinsettii y para otras especies del género.AbstractEnvironmental temperature is an important factor that regulates activity and physiological processes of ectotherms. Because sympatric species are exposed to similar thermal niche conditions, closely related species could present similar thermal requirements. This similarity may generate interspecific competition for optimal thermal space. The thermal ecology of the sympatric viviparous lizards Sceloporus lineolateralis and S. poinsettii (Sceloporus torquatus and Sceloporus poinsettii groups, respectively) were studied in natural populations in Peñón Blanco, Durango, Mexico. We found that active body temperatures and selected body temperatures were similar among species. However, S. poinsettii exhibited higher efficiency and accuracy of thermoregulation because the preferred thermal range of this species was wider. Finally their thermal preferences are analogous to those previously reported for the both groups and the genus
Quantum State During and after -Symmetric Bubble Nucleation with Gravitaional Effects
We extend our previous analysis of the quantum state during and after
-symmetric bubble nucleation to the case including gravitational effects.
We find that there exists a simple relationship between the case with and
without gravitational effects. In a special case of a conformally coupled
scalar field which is massless except on the bubble wall, the state is found to
be conformally equivalent to the case without gravity.Comment: 31 pages plain Tex file, uuencoded postscript figure file is
available from [email protected] upon request, KUNS126
Calidad térmica a través de un gradiente altitudinal para una comunidad de lagartijas en la sierra del Ajusco y el Pedregal de San Ángel, México
ResumenSe evaluó y comparó la calidad térmica del hábitat para una comunidad de lagartijas (9 especies) en un gradiente altitudinal (2 320-3 530 m) en la sierra del Ajusco y Pedregal de San Ángel para determinar si los ambientes térmicos diferentes pueden definir límites de distribución y termorregulación. Se seleccionaron 6 sitios diferentes en altitud y tipo de vegetación para monitorear la temperatura operativa ambiental. Se calculó la calidad térmica mediante la desviación de la temperatura operativa con respecto al intervalo de temperaturas seleccionadas por las lagartijas. Los resultados sugieren 3 tendencias: 1) la temperatura operativa y calidad térmica fueron más altas en los sitios más bajos (2 320 y 2 540 m) con matorral xerófilo; 2) los valores más bajos fueron registrados en los sitios con cobertura vegetal densa con bosque de pino (2 870 y 3 220 m); 3) las zonas abiertas (3 000 y 3 530 m) de pastizal alpino tuvieron valores medios de temperatura operativa y calidad. Estos resultados sugieren que la altitud y el tipo de vegetación tienen influencia en la calidad térmica y los trabajos sobre ecología térmica deben realizarse en varias escalas espaciales para entender los factores involucrados en el nicho térmico y en la termorregulación.AbstractWe evaluated and compared the thermal quality for a lizard community (9 species) in Sierra del Ajusco and Pedregal de San Ángel (central Mexico) along an altitudinal gradient (2 320-3 530 m) to determine whether different thermal environments may be influencing species distribution and thermoregulatory behavior. Six areas that differ in elevation and vegetation type are chosen to survey environmental operative temperatures. Habitat thermal quality is estimated from the mean deviation of operative temperatures from lizards’ selected thermal range. Results indicate 3 key findings: 1) operative temperature and thermal quality are higher at lower elevations (2 320 and 2 540 m), where xeric scrub vegetation was abundant; 2) thermal quality is lowest in closed-canopy pine forest (2 870 and 3 220 m); and 3) intermediate values of operative temperature and thermal quality are observed in open grassland habitat (3 000 and 3 530 m). These results support our hypothesis that elevation and vegetation type affect thermal quality and we conclude that thermal ecology studies should be conducted at multiple spatial scales to gain a better understanding of factors influencing the thermal niche and thermoregulatory profiles
Association between gender and receipt of magnetic resonance imaging (MRI) in stroke patients from Puerto Rico
Introduction: Stroke is the fifth principal cause of death in the United States and Puerto Rico and a prime cause of adult disability. Women tend to have worse outcomes post-stroke. Initial diagnoses and management of stroke include the use of computed tomography (CT) and magnetic resonance image (MRI) scans. MRI scans are more sensitive and more specific than CT scans. Still, CT scans are used more commonly. Whether differences in the choice of imaging techniques exists for gender and whether that can be a potential reason for gender differences in post-stroke outcomes it is yet unknown. The study is directed to evaluate the association between gender and receipt of a MRI in stroke patients in the Puerto Rico population. Methods: We did a secondary analysis of data collected from patients who suffered from a stroke and who participated in the Puerto Rican Cardiovascular Surveillance System (PRCSS) in 2007, 2009 and 2011. The main independent variable was gender (male and female). The dependent variable will be receipt of a MRI (alone or in combination with any other imaging modality as recorded in the medical charts). Multivariate logistic regression was used to assess for the independent associations. P-value < 0.05 for a two tailed test was considered to be statistically significant. SPSS software was used for analysis. Results: A total of 1,950 patients suffered from an ischemic stroke and participated at the PRCSS. We excluded 595 patients due to BMI ≥35 (n=135) or no recorded BMI (n=460). MRI was used for 50% of participants. Women were 85% less likely to receive a MRI compared to men in both the unadjusted (OR-0.85, 95% CI=0.11-0.20, p-value <0.001) and after adjusting for BMI, age, marital status, hypertension, and transient ischemic attacks (TIA) (OR=0.15; 95%CI: 0.11-0.20). No other variables assessed had significant independent association with the receipt of a MRI. Conclusions: We found evidence of gender disparities in the receipt of MRI during hospitalization for stroke in patients in the Puerto Rico. Women were less likely to receive MRI compared to men. Further research on potential reasons for such dispairites, increasing awareness, and testing intervention as to decrease these potential disparities are needed
Quimioesterilización de Anastrepha fraterculus (Diptera: Tephritidae) con un regulador del crecimiento de insectos
Anastrepha fraterculus is a fruit pest of economic importance in South America and northwestern Argentina. Currently, it is controlled with toxic baits but there is a demand for environmentally acceptable methodologies. The use of inhibitors of the chitin synthesis is proposed as a tool to sterilize adults in the field. The aim of this study was to evaluate the efficacy of different doses of lufenuron to generate chemosterilization in A. fraterculus. Three experiments were performed. In the first two, the product was incorporated into the diet of the adults from emergence to sexual maturity. Treated individuals from one sex were crossed with untreated individuals from the other sex. Eggs were collected and allowed embryonic development. In the third trial, untreated males and females were crossed and allowed to copulate. Subsequently, females were exposed to the product and the eggs were collected. Egg hatch was affected in the three experiments in a dose dependent way. In Experiment 3, the effect of the product was evidenced 48 hours after exposure. Fecundity was also affected when the females were the treated sex. The results show that exposure of adults to lufenuron reduces egg hatch in A. fraterculus encouraging further investigations to adapt this methodology for this species.Fil: Ruiz, J. E.. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Santilli, Melisa del Valle. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Cabrera, Debora Carina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Vera, M. T.. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: de la Vega, M. H.. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentin
First and second order optimality conditions for optimal control problems of state constrained integral equations
This paper deals with optimal control problems of integral equations, with
initial-final and running state constraints. The order of a running state
constraint is defined in the setting of integral dynamics, and we work here
with constraints of arbitrary high orders. First and second-order necessary
conditions of optimality are obtained, as well as second-order sufficient
conditions
The association between social determinants of health and self-reported diabetic retinopathy: An exploratory analysis
One-third of Americans with diabetes will develop diabetic retinopathy (DR), the leading cause of blindness in working-age Americans. Social determinants of health (SDOHs) are conditions in a person’s environment that may impact health. The objective of this study was to determine whether there is an association between SDOHs and DR in patients with type II diabetes. This cross-section study used data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS). This study included people with self-reported diabetes in the US in 2018 (n = 60,703). Exposure variables included homeownership, marital status, income, health care coverage, completed level of educa-tion, and urban vs. rural environment. The outcome variable was DR. Logistic regression analysis were applied to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Alaskan Native/Na-tive American (OR 2.11; 95% CI: 1.14–3.90), out of work (OR 2.82; 95% CI: 1.62–4.92), unable to work (OR 2.14; 95% CI: 1.57–2.91), did not graduate high school (OR 1.91; 95% CI: 1.30–2.79), only gradu-ated high school (OR 1.43; 95% CI 1.08–1.97), or only attended college or technical school without graduating (OR 1.42; 95% CI: 1.09–1.86) were SDOHs associated with DR in patients with diabetes. Health care providers should identify these possible SDOHs affecting their diabetic patients
Seasonal changes of ecophysiological responses of Hymenaea courbaril L.
The increase in the concentration of atmospheric CO2 and the likely associated climatic changes became a subject of most interest from several points of view. In Brazil, this issue is especially important due to the presence of the major tropical forests. Thus, it is important to produce scientific data about the native plants that could help to explain their role in the global carbon balance. It is obviously known that the photosynthetic process is key for this task and several experiments have been or are now being performed to understand the responses of plants to atmospheric CO2. In this work, we monitored the CO2 assimilation for 1 year, two times a week between 6am and 6pm with the aim to gather information on how Hymenaea courbaril responds during the four seasons in a year. Our results show that the higher assimilation rates occurred during the spring (the growing season) but that the periods during the day in which photosynthesis occurred were larger in the summer. A positive correlation (0.6) was observed between CO2 assimilation and the PPDF but no correlation was found with humidity. This is a large data set that describes in detail the photosynthesis related events during a whole year, which allowed the evaluation of the seasonal behaviour, a key approach to help understanding of carbon balance in the rain forest
Vector Bin Packing with Multiple-Choice
We consider a variant of bin packing called multiple-choice vector bin
packing. In this problem we are given a set of items, where each item can be
selected in one of several -dimensional incarnations. We are also given
bin types, each with its own cost and -dimensional size. Our goal is to pack
the items in a set of bins of minimum overall cost. The problem is motivated by
scheduling in networks with guaranteed quality of service (QoS), but due to its
general formulation it has many other applications as well. We present an
approximation algorithm that is guaranteed to produce a solution whose cost is
about times the optimum. For the running time to be polynomial we
require and . This extends previous results for vector
bin packing, in which each item has a single incarnation and there is only one
bin type. To obtain our result we also present a PTAS for the multiple-choice
version of multidimensional knapsack, where we are given only one bin and the
goal is to pack a maximum weight set of (incarnations of) items in that bin
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