A Real-Time FPGA-Based Metaheuristic Processor to Efficiently Simulate a New Variant of the PSO Algorithm.

Nowadays, high-performance audio communication devices demand superior audio quality. To improve the audio quality, several authors have developed acoustic echo cancellers based on particle swarm optimization algorithms (PSO). However, its performance is reduced significantly since the PSO algorithm suffers from premature convergence. To overcome this issue, we propose a new variant of the PSO algorithm based on the Markovian switching technique. Furthermore, the proposed algorithm has a mechanism to dynamically adjust the population size over the filtering process. In this way, the proposed algorithm exhibits great performance by reducing its computational cost significantly. To adequately implement the proposed algorithm in a Stratix IV GX EP4SGX530 FPGA, we present for the first time, the development of a parallel metaheuristic processor, in which each processing core simulates the different number of particles by using the time-multiplexing technique. In this way, the variation of the size of the population can be effective. Therefore, the properties of the proposed algorithm along with the proposed parallel hardware architecture potentially allow the development of high-performance acoustic echo canceller (AEC) systems.

Bromadiolona: un caso judicial relacionado con la muerte de abejas / Bromadiolone: a judicial case related to bees death

Como resultado de una investigación impulsada por la justicia, se analizaron muestras provenientes de un posiblederrame intencional de plaguicidas sobre colmenas con abejas. En los análisis realizados se utilizó GC-MS previa extracción con solventes orgánicos. Debido a dificultades iniciales en la identificación de plaguicidas sobre tres de las muestras, se procedió alreprocesamiento de los cromatogramas utilizando selección de las relaciones de masas m/z 158, 173 y 143. Utilizando esa herramienta analítica se obtuvieron los correspondientes cromatogramas, y los espectros de masas con coincidencia frente al divulgado para el producto de descomposición de bromadiolona (PDB), determinando que tanto las abejas como las colmenas habían tenido contacto con bromadiolona (3-[3-(4’-bromobifenil-4-il)- 3-hidroxi-1-fenilpropil]-4- hidroxicumarina), un anticoagulantecumarínico de utilización agraria para combatir roedores, que parece ser prácticamente no tóxico para las abejas según informes internacionales. Se observó que en la literatura no se halla propuesta una estructura química definida para el PDB, lo cual podría constituir el fundamento para encarar trabajos futuros con el fin de elucidar el comportamiento de la droga madre enel contexto del caso.

As a result of an investigation boosted by ordinary justice, samples from a probable deliberate spill of pesticide over bees and hives were analyzed. Solvent extractions and then GC-MS were used to perform the tests. Due to difficulties since the beginning in pesticide identification upon three samples, chromatograms were reprocessed using mass selection at m/z 158, 173 y 143 mass rates. The correspondent chromatograms were gathered by these analytical tool, and their mass spectrums were found coincident with the previously reported as bromadiolone decomposition product (BDP), showing that hives as well asbees had been in contact with bromadiolone (3-[3-(4’-bromobiphenyl-4-yl)- 3-hydroxy-1-phenylpropyl]-4- hydroxycoumarin) - a coumarin rodenticide (anticoagulant) for agricultural use – which seems to be, according to international reports, practically non toxic for bees. It was observed that in the literature has not been proposed a defined chemical structure for BDP, so this could bea challenge for a future research in order to clarify its behavior in a similar situation.

Brain glutamate levels are decreased in Alzheimer's disease: a magnetic resonance spectroscopy study.

Glutamate (Glu) is the most abundant excitatory neurotransmitter in the central nervous system (CNS) and is involved in the pathophysiology of Alzheimer's disease (AD) in which there is an increased excitotoxicity. Biochemical composition of living tissues including the levels of Glu was analyzed by magnetic resonance spectroscopy (MRS). Previous reports point to decreased levels of Glu in AD. As Glu plays an important role in memory, we hypothesize that Glu levels are decreased in patients with AD when compared with controls. A consecutive sample of 30 patients with mild-to-moderate AD underwent H-MRS with the voxel placed in the bilateral posterior cingulate gyrus. For comparison purposes, we carried out the same technique in 68 patients with mild cognitive impairment (MCI) and in 26 controls. The healthy controls had higher metabolite levels of N-acetyl-aspartate (NAA) than patients with MCI and AD. In turn, patients with MCI and the controls had higher levels of Glu than in patients with AD. The differences were significant in the analysis of variance (ANOVA) test model corrected for age. In the post hoc analysis, the most remarkable differences were seen between patients with AD and the rest (patients with MCI and the controls). In AD, the levels of Glu and NAA are decreased in comparison with MCI and normality, which reflects loss of neurons.

The cycloxygenase 2 (COX-2) story: it's time to explain, not inflame.

Despite initial promising reports that anti-inflammatory properties of cycloxygenase-2 (COX-2) inhibitors may confer anti-atherosclerosis effects and stabilize the atherosclerotic plaque, subsequent data from long-term clinical trials have shown that selective COX-2 inhibitors are associated with increased risk of cardiovascular events. The commonly cited explanation is that selective inhibition of COX-2 leads to depletion of prostacyclin, whereas the production of pro-thrombotic thromboxane by means of cycloxygenase-1 (COX-1) is unopposed. This hypothesis seems unlikely as the overall explanation, because low-dose aspirin does not decrease the increased risk associated with COX-2 inhibitors. Moreover, the risk associated with nonselective COX inhibitors may be similar to selective COX-2 inhibitors. Alternative hypotheses include (1) elevated blood pressure, (2) abnormal vascular remodeling, (3) inhibition of protective mechanisms against ischemia-reperfusion injury, and (4) inhibition of 15-epi-lipoxin production. Varying results in different experimental models may be related to the fact that COX-2 is involved in numerous cellular functions. Inhibiting COX-2 in inflammatory cells may have favorable effects, whereas in organs such as the heart and brain and/or blood vessels may have deleterious effects. Currently, the "selective COX-2 inhibitors" are not selective in the sense that they inhibit COX-2 in all tissues without predilection to inflammatory cells and, as a result, may summate to increase the risk of cardiovascular events.

Infective coronary aneurysms: a complication of percutaneous coronary intervention.

We present the case of a patient who developed infective coronary artery aneurysms after percutaneous coronary artery intervention. We describe the patient's clinical presentation, diagnosis, and treatment, and we review the pertinent medical literature.

B-type natriuretic peptide is not a marker of ischemia during dobutamine stress echocardiography.

Elevated levels of B-type natriuretic peptide (BNP) have been reported in association with exercise-induced ischemia. Data regarding BNP as a marker of ischemia during dobutamine stress echocardiography (DSE) are not conclusive. This study was designed to evaluate changes in BNP during DSE. A total of 74 patients referred to rule out ischemia by DSE were enrolled in the study. All patients had DSE using standard protocol. Of 74 patients enrolled, 6 were excluded because of nondiagnostic tests. Of the remaining 68 patients, 15 had positive DSE and 53 were negative for ischemia. The BNP levels (mean +/- SD) in the patients without ischemia were 42.5 pg/mL (+/-SD 47.6) at baseline and 41.9 pg/mL (+/-SD 48.9) at peak, and the measurements in the patients with ischemia were 90 pg/mL (+/-SD 171.7) at baseline and 88 pg/mL (+/-SD 149.2) at peak. BNP levels do not change during DSE with or without evidence of ischemia.

Biomarcadores de exposición a tabaco ambiental en Argentina / Biomarkers of environmental tobacco smoke (ETS) exposure in Argentine

Health effects of smoking have been studied intensely and there is substantial evidence on the harmful consequences for health that produces. In the last 20 years the effect of environmental tobacco smoke has been studied and researchers as governmentalagencies have concluded that involuntary smoking is one of the causes of lung cancer and cardiovascular illness in adults and of adverse consequences, like the syndrome of sudden death of the nursing, asthma, bronchitis and pneumonia in small children (1,2). Epidemiological questionnaires have been the usual method to determine exposition to environmental tobacco,but they present bias and low sensibility that can lead to misinterpretations of associations between exposition and illness (3,4). Cotinine, a metabolite from nicotine with a relatively short half life in plasma (about 20-30 hours), is useful as a biomarker for categorization and verification of a recent exposition (5). The goal of this work was to determine the level of exposition to environmentaltobacco smoke in a group of adolescents of the city of Mar del Plata, Argentina.

Recurrence of varus deformity after proximal tibial osteotomy in Blount disease: long-term follow-up.

In a retrospective review of 74 tibial osteotomies performed for Blount disease, the patients were divided into three groups based on age and treatment. Group A (26 osteotomies), 4 years old or younger, and group B (34 osteotomies), older than 4 years, were treated the same with osteotomy and crossed pins. Group C (14 osteotomies), older than 4 years, was treated with osteotomy and external fixator. At 6 years of follow-up, the recurrence of varus deformity was 46%, 94%, and 72% in groups A, B, and C, respectively. There was no correlation between recurrence of varus deformity and preoperative deformity angle or degree of surgical correction. Fixation with crossed pins or external fixator was not a factor. Surgery at 4 years old or younger and correction of the postoperative deformity angle in valgus may obviate recurrence of varus deformity in Blount disease at long-term follow-up.