Global design of analog cells using statistical optimization techniques

We present a methodology for automated sizing of analog cells using statistical optimization in a simulation based approach. This methodology enables us to design complex analog cells from scratch within reasonable CPU time. Three different specification types are covered: strong constraints on the electrical performance of the cells, weak constraints on this performance, and design objectives. A mathematical cost function is proposed and a bunch of heuristics is given to increase accuracy and reduce CPU time to minimize the cost function. A technique is also presented to yield designs with reduced variability in the performance parameters, under random variations of the transistor technological parameters. Several CMOS analog cells with complexity levels up to 48 transistors are designed for illustration. Measurements from fabricated prototypes demonstrate the suitability of the proposed methodology

A SENSITIVITY ANALYSIS OF ORGANIC VERSUS CONVENTIONAL SYSTEMS OF SHEEP-FARMING

In the Mediterranean Agriculture, the organic production constitutes a real possibility for sustainable development, it can keep a population in these areas and provide it with a decent work. This paper try to establish differences between conventional and organic systems of production, so that observation of these differences would lead to conclusions relating to the level of efficiency of one system as against the other. To achieve this objective, the research team analyzed the evolution of seventeen milk sheep farms in various places in the Castilla y León Region for a whole year. The study consisted in the modeling of the results of a Cobb-Douglas production function. The findings reveal that organic farms have higher production levels with the same combination of inputs. This result is a guarantee of future for this type of production and guarantee of feasibility for these areas

Stress estimation by the prefrontal cortex asymmetry: Study on fNIRS signals

sure the brain hemodynamic activity in applications to evaluate affective disorders and stress. Using two wavelengths of light, it is possible to monitor relative changes in the concentrations of oxyhemoglobin and deoxyhemoglobin. Besides, the spatial asymmetry in the prefrontal cortex activity has been correlated with the brain response to stressful situations. Methods: We measured prefrontal cortex activity with a NIRS multi-distance device during a baseline period, under stressful conditions (e.g., social stress), and after a recovery phase. We calculated a laterality index for the contaminated brain signal and for the brain signal where we removed the influence of extracerebral hemodynamic activity by using a short channel. Results: There was a significant right lateralization during stress when using the contaminated signals, consistent with previous investigations, but this significant difference disappeared using the corrected signals. Indeed, exploration of the susceptibility to contamination of the different channels showed non-homogeneous spatial patterns, which would hint at detection of stress from extracerebral activity from the forehead. Limitations: There was no recovery phase between the social and the arithmetic stressor, a cumulative effect was not considered. Conclusions: Extracerebral hemodynamic activity provided insights into the pertinence of short channel corrections in fNIRS studies dealing with emotions. It is important to consider this issue in clinical applications including modern monitoring systems based on fNIRS technique to assess emotional states in affective disorders

Índices para la evaluación de un seguidor solar

The usage of solar trackers in solar energy technologies represents an alternative to increase the capture of solar radiation. However, the costs involved convert it into a prohibitive technology, having indexes and procedures that allow for its evaluation and determination of the viability of its use is of vital importance at the time of deciding its implementation and so to form the objective of this study. In the investigation carried out, the indexes of average gain, comparative efficiency and profitability are introduced and a procedure for the evaluation is developed, as a contribution to the decision-making process as to whether or not to use a solar tracker. It is confirmed that the use of trackers is completely viable when used with higher power technologies. Furthermore, it is shown that theoretically, the average gain index is higher than the values currently registered in scientific literature. Such factors support the possibility of designing and developing solar trackers with a higher gain, lower production costs and lower consumption indexes, as a way for their mass use in low power photovoltaic generators.El uso de los seguidores solares como tecnología de aprovechamiento de energía solar representa una alternativa para incrementar la captación de radiación solar. Sin embargo, sus costos lo convierten en una tecnología prohibitiva, por lo que disponer de índices y procedimientos que permitan su evaluación para determinar la viabilidad de uso es una herramienta de extrema importancia a la hora de decidir sobre su utilización y constituye el objetivo de este trabajo. Con la investigación realizada se introducen los índices de ganancia media, eficiencia comparativa y de utilidad y se desarrolla un procedimiento de evaluación, como contribución a la toma de decisiones sobre el uso o no de un seguidor solar. Se corrobora que su uso es totalmente viable mientras mayor es la potencia de las tecnologías en las cuales se utiliza. Además, se muestra que teóricamente el índice medio de ganancia es mayor que los valores registrados actualmente en la literatura científica. Tales elementos apoyan la posibilidad de diseñar y desarrollar seguidores solares con mayor ganancia, menores costos de fabricación y menores índices de consumo, como vía para su utilización masiva en generadores fotovoltaicos de baja potencia

Role of mTOR-regulated autophagy in spine pruning defects and memory impairments induced by binge-like ethanol treatment in adolescent mice

Adolescence is a brain maturation developmental period during which remodeling and changes in synaptic plasticity and neural connectivity take place in some brain regions. Different mechanism participates in adolescent brain maturation, including autophagy that plays a role in synaptic development and plasticity. Alcohol is a neurotoxic compound and its abuse in adolescence induces neuroinflammation, synaptic and myelin alterations, neural damage and behavioral impairments. Changes in synaptic plasticity and its regulation by mTOR have also been suggested to play a role in the behavioral dysfunction of binge ethanol drinking in adolescence. Therefore, by considering the critical role of mTOR in both autophagy and synaptic plasticity in the developing brain, the present study aims to evaluate whether binge ethanol treatment in adolescence would induce dysfunctions in synaptic plasticity and cognitive functions and if mTOR inhibition with rapamycin is capable of restoring both effects. Using C57BL/6 adolescent female and male mice (PND30) treated with ethanol (3 g/kg) on two consecutive days at 48-hour intervals over 2 weeks, we show that binge ethanol treatment alters the density and morphology of dendritic spines, effects that are associated with learning and memory impairments and changes in the levels of both transcription factor CREB phosphorylation and miRNAs. Rapamycin administration (3 mg/kg) prior to ethanol administration restores ethanol-induced changes in both plasticity and behavior dysfunctions in adolescent mice. These results support the critical role of mTOR/autophagy dysfunctions in the dendritic spines alterations and cognitive alterations induced by binge alcohol in adolescence

CHRONOFALLS: A multicentre nurse-led intervention in the chronoprevention of in-hospital falls in adults

Background: Falls are among the most common and serious adverse events for hospitalised patients. In-hospital falls pose a major medical and economic challenge for public health worldwide. Nevertheless, the issue is often addressed without regard to certain relevant variables such as the time of the fall. The aim of this study was to determine the effect of the implementation of a nurse-led intervention based on the temporal patterns of falls and their aetiology on the occurrence of falls. Methods: A mixed-method research design was carried out in three phases: a) a longitudinal prospective study (audits, chronobiological analyses and implementation of a multicentre nurse-led intervention based on temporal patterns of falls); b) a retrospective study of fall records; and c) a qualitative study based on focus groups. The protocol was published in 2021. Results: A difference was observed in the number of fall records before and after the chronopreventive intervention (retrospective: 64.4% vs. 35.6%; p < 0,001). According to the interrupted series analysis, considering the influence of the COVID-19 pandemic, a reduction in falls of 2.96% (95% CI 1.70%-4.17%) was observed. The concepts of falls, the COVID-19 pandemic and the causes of non-registration have emerged as categories for qualitative analysis. Conclusions: A multicentric nurse-led program based on tailored organisational, educational and behavioural chronopreventive measures seems to lead to a reduction in the number of in-hospital falls. The findings of the present study, highlighting the implementation of chronopreventive measures, can serve as a basis for future health policies

Towards a Precision Cosmology from Starburst Galaxies at z>2

This work investigates the use of a well-known empirical correlation between the velocity dispersion, metallicity, and luminosity in H beta of nearby HII galaxies to measure the distances to HII-like starburst galaxies at high redshifts. This correlation is applied to a sample of 15 starburst galaxies with redshifts between z=2.17 and z=3.39 to constrain Omega_m, using data available from the literature. A best-fit value of Omega_m = 0.21 +0.30 -0.12 in a Lambda-dominated universe and of Omega_m = 0.11 +0.37 -0.19 in an open universe is obtained. A detailed analysis of systematic errors, their causes, and their effects on the values derived for the distance moduli and Omega_m is carried out. A discussion of how future work will improve constraints on Omega_m by reducing the errors is also presented.Comment: 7 pages, 3 figures, accepted for publication in MNRA