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Author(s): María Morales-Suárez-Varela [sup.1] [sup.2 ] [sup.3] , Fernando González-Candelas [sup.2] [sup.3] [sup.4] , Jenaro Astray [sup.5] , Jordi Alonso [sup.2] [sup.6] [sup.7 ] , Ady Castro [sup.8] , Rafael [...]

The aim of this study was to investigate the main characteristics of non-vaccinated pregnant women who were hospitalized for influenza A (H1N1) pdm09 pandemic versus pregnant women hospitalized for non-influenza-related reasons in Spain, and to characterize the clinical presentation of the disease in this population to facilitate early diagnosis and future action programmed. Understanding influenza infection during pregnancy is important as pregnant women are a high-risk population for increased morbidity from influenza infection. We investigated the socio-demographic and clinical features of 51 non-vaccinated, pregnant women infected with the pandemic influenza A (H1N1) virus in Spain (cases) and compared them to 114 controls (non-vaccinated and non infected pregnant women) aged 15-44 years. Substantial and significant odd ratios (ORs) for pandemic influenza A (H1N1) were found for the pregnant women who were obese compared with controls (body mass index > 30) (OR 3.03; 95% confidence intervals 1.13-8.11). The more prevalent symptoms observed in pandemic influenza-infected pregnant women were high temperature, cough (82.4%), malaise (80.5%), myalgia (56.1%), and headaches (54.9%). Our results suggest that the initial symptoms and risk factors for infection of pregnant women with the influenza A (H1N1) pdm09 virus are similar to the symptoms and risk factors for seasonal influenza, which make early diagnosis difficult, and reinforces the need to identify and protect high-risk groups. Keywords Influenza A (H1N1) * Pregnancy * Pandemic * Symptomatology * Clinical characteristics, Introduction In March 2009, an outbreak of a novel influenza A (H1N1) pdm09 virus, now commonly referred to as the 2009 H1N1 pandemic influenza, was detected in Mexico and spread [...]

A new family of single-stage super Class-AB operational transconductance amplifiers (OTAs) suitable for low-voltage operation and low power consumption is presented. Three novel topologies are proposed featuring simplicity and compactness. They are based on the combination of adaptive biasing techniques for the differential input stage and nonlinear current mirrors for the active load that provide additional dynamic current boosting. The OTAs have been fabricated in a standard 0.5-[micro]m CMOS process. Experimental results show a greatly improved slew rate by factors 30-60 and gain-bandwidth product by factors 11.5-17 when compared to a classical Class-A OTA. The circuits are operated at [+ or -] 1-V supply voltage with only 10 [micro]A of bias current. Index Terms--Adaptive biasing, analog CMOS circuits, CMOS amplifiers, Class-AB amplifiers, low-power and low-voltage CMOS circuits, operational transconductance amplifier (OTA).

A simple and efficient low-voltage two-stage operational amplifier with Class-AB output stage is introduced. It has a large effective output current boosting factor (~50) and close to a factor 2 bandwidth enhancement. This is achieved at the expense of minimum increase in circuit complexity and no additional static power dissipation. Experimental verification of the characteristics of the proposed circuit is provided. Index Terms--Analog integrated circuits, Class-AB amplifiers, low-voltage analog circuits, operational amplifiers.

In this paper, a basic cell for low-power and/or low-voltage operation is identified. It is evidenced how different versions of this cell, coined as 'flipped voltage follower (FVF)' have been used in the past for many applications. A detailed classification of basic topologies derived from the FVF is given. In addition, a comprehensive fist of recently proposed low-voltage/low-power CMOS circuits based on the FVF is given. Although the paper has a tutorial taste, some new applications of the FVF are also presented and supported by a set of simulated and experimental results. Finally, a design example showing the application of the FVF to build systems based on translinear loops is described which shows the potential of this cell for the design of high-performance low-power/low-voltage analog and mixed-signal circuits. Index Terms--Analog circuits, analog integrated circuits, continuous time filters, differential amplifiers, low-power design, low-voltage design.

Several studies are conducted to determine the polymorphic mutation frequencies of the various clinical, as well as environmental Stenotrophomonas maltophilia populations. The environmental and clinical populations are shown to exhibit low and high mutation frequencies respectively.

Two series of activated carbon is prepared by reaction of a char (from olive stones) with supercritical water (SCW) with the aim of studying the effect of temperature and residence time on the development of porosity. The results are compared with those obtained using the same char but with classical activation with stem.