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Although both obesity and ageing are risk factors for cognitive impairment, there is no evidence in Chile on how obesity levels are associated with cognitive function. Therefore, the aim of the present study was to investigate the association between adiposity levels and cognitive impairment in older Chilean adults. This cross-sectional study includes 1384 participants, over 60 years of age, from the Chilean National Health Survey 2009–2010. Cognitive impairment was evaluated using the Mini-Mental State Examination. BMI and waist circumference (WC) were used as measures of adiposity. Compared with people with a normal BMI, the odds of cognitive impairment were higher in participants who were underweight (OR 4·44; 95 % CI 2·43, 6·45; P < 0·0001), overweight (OR 1·86; 95 % CI 1·06, 2·66; P = 0·031) and obese (OR 2·26; 95 % CI 1·31, 3·21; P = 0·003). The associations were robust after adjustment for confounding variables. Similar results were observed for WC. Low and high levels of adiposity are associated with an increased likelihood of cognitive impairment in older adults in Chile.
To compare functional endoscopic sinus surgery with a combined approach (functional endoscopic sinus surgery plus Caldwell–Luc procedure) for the treatment of paediatric antrochoanal polyp, in terms of antrochoanal polyp recurrence and safety.
This retrospective case series comprises 27 paediatric patients with recurrent antrochoanal polyp, treated from January 2010 to January 2018.
The average age of the patients at the time of diagnosis was 10.4 ± 2.49 years. The recurrence rate after functional endoscopic sinus surgery alone was 72.9 per cent, compared with 12.5 per cent after functional endoscopic sinus surgery plus the Caldwell–Luc procedure (p < 0.00001). No complications were reported during surgery or follow up.
The correct identification of the origin of the antrochoanal polyp and an adequate returning of maxillary ventilation by widening the ostium can prevent recurrences. Although functional endoscopic sinus surgery continues to be the ‘gold standard’ for antrochoanal polyp treatment, in cases of revision surgery, a combined approach could ensure the complete removal of the polyp through the two openings.
The present investigation focused on evaluating the effects of different amounts of precipitates on tension and hardness properties of a Ti–6Al–4V alloy, for this, two sets of samples with bimodal and equiaxed microstructures were obtained by heat treatment process. After this, the samples were aged at 545 °C for holding times of 100 and 200 h. Observation of the aged samples in the scanning electron microscope revealed fine α2 (Ti3Al) particles precipitating in the α matrix of the alloy. Uni-axial tension tests and Vickers microhardness measurements were conducted on the unaged and aged samples. Experimental results show that ultimate strength and hardness of bimodal and equiaxed microstructures are significantly affected by the heat treatment applied to produce such microstructures. Also, it was found that the precipitation of α2 particles drastically reduced the plastic response of the Ti–6Al–4V alloy.
This work proposes a strategy for position control and obstacle avoidance in a quadcopter based on constrained generalized predictive control and geometric attitude control. The approach allows real-time trajectory tracking using optimal control actions and avoids collisions with static obstacles whose position is known. An experimental validation of the proposed controller is presented.
In recent years, many Latin American countries (LACs) have embarked upon trade liberalization drives. This article reviews the radical changes in trade policy which this has entailed, together with the current and foreseeable results, and offers some policy recommendations regarding complementary measures.
The first sustained experience with trade liberalization in recent decades was in Chile, which launched a process in the 1970s that, by the end of that decade, had made its economy one of the most open in the world.
During the early 1990s, many Latin American countries enjoyed exceptionally strong economic growth, which has been credited with making possible substantial reductions in their rates of poverty. However, the collapse of capital flows to Latin America that began in 1995 portends a decline in the region's economic growth. If these countries now register growth rates that are only modestly positive (on the order of 1-3%), the question then arises as to whether this progress in overcoming poverty is bound to stall.
Despite new rhetoric to the contrary, Latin Americans have relied on growth almost exclusively as the way to overcome poverty. The distribution of income has changed very little over the past decade and, where change did occur, in many cases it has been for the worse.
Economic development under a capitalist market economy is usually not a smooth process. In addition, restructuring the economy with the aim of promoting a freer market economy often entails high economic costs as well. This article has two goals: (1) it will outline the inter-relationship between the restructuring of the economy now taking place in both Bolivia and Peru and how this process is affected by the illicit coca drug sector in each of those countries; and (2) it will discuss the domestic anti-drug policies in each and how, or to what extent, these are affected by the anti-drug policies of the United States. On the one hand, the illegal drug industry may have served to ameliorate the costs of restructuring; at the same time, it may also have made economic adjustment somewhat more difficult.
One of the most dramatic political-economic changes over the last 15 years has been the shift in patterns of international finance. At the beginning of the 1980s, a select group of prosperous Third World nations had privileged access to an enormous volume of commercial bank credit. They could also attract fairly important levels of direct investment. For all practical purposes, finance was no longer a binding constraint on the development strategies of this group of countries. Although poorer developing nations could not rely on private credit or investment, many of them had access to substantial amounts of funds via bilateral donors and the multilateral institutions.
In recent years, Chile has arrived at a significant consensus regarding a number of subjects central to the country's development; and, notwithstanding certain important differences between the Concertación government and its opposition, there is considerable agreement regarding certain basic aspects of economic growth which will doubtless continue to be maintained in the mid-to-long run.
The official policy, as laid down by the government, is that Chile's economy is now oriented toward achieving growth with social equity, and that the way to reach those goals is by strengthening the country's insertion into the international economy, since the world is now moving towards a globalization which no country can afford to ignore. Given this new reality, the Chilean economy is also moving to take part in this process in a strategy that has proved fairly successful in recent years.
Two metal fillers with TiC nanoparticles (TiC NPs) of less than 100 nm for the overlay process is an alternative to hardfacing for treating surfaces subjected to severe wear. In this work, the effect of tribological behavior for TiC NPs addition on two Co-based filler materials, as well as the dilutions, was studied. Mixtures of Co-based filler metals without and with 0.5% and 2% TiC NPs were deposited onto D2 steel plates using PTA (Plasma Transferred Arc). The BET surface area was 0.17 m2 g-1 and 0.31 m2 g-1, respectively, for Stellite 6 and 12. The distribution of ca 23% macroporous for Stellite 6 was sufficient to get inside the TiC NPs, as well as in the case of Stellite 12, with a pore distribution of ca 13%. Stellite 12 has an increase in the dilutions (70%) and enthalpies showed endothermic reactions. Stellite 6 with NPs was determined to be most effective in increasing the wear resistance.
TAOS II is a next-generation occultation survey with the goal of measuring the size distribution of the small end of the Kuiper Belt (objects with diameters 0.5–30 km). Such objects have magnitudes r > 30, and are thus undetectable by direct imaging. The project will operate three telescopes at San Pedro Mártir Observatory in Baja California, México. Each telescope will be equipped with a custom-built camera comprised of a focal-plane array of CMOS imagers. The cameras will be capable of reading out image data from 10,000 stars at a cadence of 20 Hz. The telescopes will monitor the same set of stars simultaneously to search for coincident occultation detections, thus minimising the false-positive rate. This talk described the project, and reported on the progress of the development of the survey infrastructure.
A segment of the Milky Way in Norma, from ℓ = 327° to 335°, |b|≦ 1°, has been studied as part of the Columbia CO survey of the fourth galactic quadrant. Description of the entire survey is given by Cohen elsewhere in this volume.
ET And is a binary system with a B9 Si star as the main component (Porb = 48.308d, e=0.46). Controversial claims in the literature concerning pulsation with periods ranging from few minutes to few hours and with variable amplitudes indicated a challenging target and motivated us to organize several photometric and spectroscopic observing campaigns. The problem with pulsation of ET And is that Teff and log g put this star in the cool domain of Slowly Pulsating B-type (SPB) stars, but the pulsation periods would be too short by a factor of about four, relatively to the shortest hitherto known periods for SPB stars.