Performance of Vertically Stacked Horizontal Si Nanowires Transistors: A 3D Monte Carlo / 2D Poisson Schrodinger Simulation Study

In this paper we present a simulation study of 5nm vertically stacked lateral nanowires transistor (NWTs). The study is based on calibration of drift-diffusion results against a Poisson-Schrodinger simulations for density-gradient quantum corrections, and against ensemble Monte Carlo simulations to calibrate carrier transport. As a result of these calibrated results, we have established a link between channel strain and the device performance. Additionally, we have compared the current flow in a single, double and triple vertically stacked lateral NWTs

Associations between physical fitness and adiposity among school-age children from Monteria, Colombia

Los niveles bajos de condición física se han asociado con adiposidad elevada. Ambas condiciones pueden predecir alteraciones cardiovasculares y metabólicas. El objetivo fue analizar la relación entre la condición física y los indicadores antropométricos de adiposidad. Estudio transversal, en 534 escolares de 6 a 12 años de edad del municipio de Montería. Se midió la condición cardiorrespiratoria (CCR), flexibilidad, fuerza explosiva de miembros inferiores (FEMI), fuerza resistencia abdominal (FRA), Índice de Masa Corporal (IMC), masa adiposa (PMA), y perímetro abdominal (PA). Las asociaciones entre adiposidad y la condición física se analizaron con modelos de regresión logística. Se encontró que el sobrepeso está asociado a baja CCR (ORa = 2,7, p<0,0001); el PA elevado está asociado a baja FRA (ORa = 2,2, p<0,02), y a baja CCR (ORa = 3,3, p<0,001); el PMA elevado está asociado a baja CCR (ORa = 2,7, p<0,0001). Conclusión, la condición física está asociada a la adiposidadLow physical fitness levels have been associated with elevated adiposity. Both conditions may predict cardiovascular and metabolic alterations. The objective was to analyze the associations between health-related physical fitness and adipose. A cross-sectional study in 534 school-age children aged 6-12 in Monteria, Colombia. Measurements included cardiorespiratory fitness (CCR), flexibility, explosive strength of lower limbs (FEMI), abdominal strength endurance (ASE), body mass index (BMI), percentage of adipose mass (PAM), and waist circumference (WC). The associations between adiposity and physical fitness were calculated by logistic regression models. Results indicate that overweight is associated with low CCR (aOR = 2.7, p<0.0001). Elevated PA was associated with low ASE (aOR = 2.2, p<0.02), and with low CCR (aOR = 3.3, p<0.001). Elevated PMA was associated with low CCR (aOR=2.7, p<0.0001). In conclusion, physical fitness is associated with adiposity

2D-TCAD Simulation on Retention Time of Z2FET for DRAM Application

Traditional memory devices are facing more challenges due to continuous down-scaling. 6T-SRAM suffers from variability [1-2] and reliability [3-4] issues, which introduce cell stability problems. DRAM cells with one transistor, one capacitor (1T1C) struggle to maintain refresh time [5-6]. Efforts have been made to find new memory solutions, such as one transistor (1T) solutions [7-9]. Floating body based memory structures are among the potential candidates, but impact ionization or band-to-band tunnelling (B2BT) limits their refresh time [10]. A recently proposed zero impact ionization and zero subthreshold swing device named Z2FET [9, 11-12] has been demonstrated and is a promising candidate for 1T DRAM memory cell due to technology advantages such as CMOS technology compatibility, novel capacitor-less structure and sharp switching characteristics. In the Z2FET memory operation, refresh frequency is determined by data retention time. Previous research [11-12] is lacking systematic simulation analysis and understanding on the underlying mechanisms. In this paper, we propose a new simulation methodology to accurately extract retention time in Z2FET devices and understand its dependency on applied biases, temperatures and relevant physical mechanisms. Since the stored ‘1’ state in Z2FET is an equilibrium state [9, 11-12] and there is no need to refresh, we will concentrate on state ‘0’ retention. Two types of ‘0’ retention time: HOLD ‘0’ and READ ‘0’ retention time will be discussed separately

Testing an ecophysiological mechanism of morphological plasticity in pupfish and its relevance to conservation efforts for endangered Devils Hole pupfish

Imperiled species that have been translocated or established in captivity can show rapid alterations in morphology and behavior, but the proximate mechanisms of such phenotypic changes are rarely known. Devils Hole pupfish (Cyprinodon diabolis) are endemic to a single desert pool and are characterized by a small body, large head and eyes, and lack of pelvic fins. To lessen the risk of extinction, additional populations of C. diabolis were established in artificial refuges. Yet, pupfish in these refuges rapidly shifted to a larger body, smaller head and eyes, and greater body depth. Here we examined how food availability and temperature, which differ between these habitats, influence morphological development in closely related Amargosa River pupfish (Cyprinodon nevadensis amargosae). We were interested in knowing whether these environmental factors could developmentally shift Amargosa River pupfish toward the morphology typical of pupfish in Devil\u27s Hole. By regulating food ration, we created groups of pupfish with low, medium and high growth rates. Pupfish with low growth showed proportionally larger head and eyes, smaller body depth, and reduction in pelvic fin development. Elevated temperature further inhibited pelvic fin development in all treatments. Pupfish in the low growth group also showed reduced levels of thyroid hormone, suggesting a possible physiological mechanism underlying these morphological changes. To test this mechanism further, pupfish were reared with goitrogens to pharmacologically inhibit endogenous thyroid hormone production. Pupfish given goitrogens developed larger heads and eyes, shallower bodies, and reduced pelvic fins. Taken together, our results suggest that changes in environmental factors affecting the growth and thyroid hormone status of juvenile pupfish may play a developmental role in generating the morphological differences between C. diabolis in Devil\u27s Hole and the refuges. These findings illustrate the need to incorporate a mechanistic understanding of phenotypic plasticity into conservation strategies to preserve imperiled fishes

Molecular cloning and sequence analysis of multiple cDNA variants for thyroid-stimulating hormone β subunit (TSHβ) in the fathead minnow \u3cem\u3e(Pimephales promelas)\u3c/em\u3e

We cloned and sequenced full-length cDNAs encoding the β subunit of thyroid-stimulating hormone (TSHβ) from the pituitary of fathead minnow (Piephales promelas)using 5\u27-and 3\u27-rapid amplification of cDNA ends (RACE). Three cDNA variants for TSHβ with lengths of 1184-, 1093-, and 818-bp were identified. The cDNA variant of 1184-bp included 453-bp of open-reading frame and 610-bp of 3\u27 UTR followed by a poly(A)site. This cDNA encodes 150 amino acids including a 19 residue signal peptide and a mature TSHβ protein of 131 residues with sequence identities of 97–53% to other fishes and 42–39% to mammals. The 1093-bp cDNA variant was identical to the 1184-bp variant in the open-reading frame, but contained a deletion of 40-bp in the 3\u27 UTR. The 818-bp cDNA variant, however, contained 498-bp of open-reading frame followed by 227-bp of 3\u27 UTR and a poly(A)site. The deduced amino acid sequence for this cDNA variant showed 99.2% homology with the 1184-and 1093-bp variants of TSHβ, but a single deletion of 332bp nucleotides spanning the predicted stop codon and 3\u27 UTR resulted in a deduced amino acid sequence with 15 additional residues on the C terminus. The presence of this 818-bp cDNA variant in the pituitary was further confirmed by PCR using primers developed to the 5\u27 and 3\u27 UTR. PCR and Southern blot analyses of genomic DNA suggested only one gene for TSHβ. Sequencing of this gene revealed a hairpin loop structure of approximately 300-bp located in the 3\u27 UTR and corresponding to the region of the 332-bp deletion in the 818-bp transcript

HIV/AIDS and pregnancy-related deaths in Blantyre, Malawi

Background: HIV/AIDS epidemic is one of the major factors affecting women’s health and impeding national efforts to improve it especially in sub-Saharan Africa. Current evidence indicates that HIV/ AIDS is increasingly becoming a major cause or contributing factor to pregnancy-related deaths, almost overtaking the “traditional” causes and factors. Objectives: To survey the contribution of HIV infection and AIDS to pregnancy-related deaths in Blantyre, Malawi. Design: A retrospective, descriptive, facility-based survey. Setting: The Queen Elizabeth Central Teaching Hospital, Blantyre, Malawi. Subjects: All women recorded to have had pregnancy-related deaths between January 1, 1999 and December 31, 2000. Results: There were 204 maternal deaths, 154 (75.5%) direct, the top five causes being puerperal sepsis (39.0%), postabortion complications (31.2%), obstetric haemorrhage (14.3%), eclampsia (8.4%) and ectopic pregnancy (3.9%). At least 38 (18.6%) of the total were HIV positive or had AIDS. The main causes of deaths amongst these were meningitis (23.7%), pneumonia (18.4%), puerperal sepsis (13.2%), postabortal sepsis (10.5%), severe anaemia (10.5%) and pulmonary tuberculosis (10.5%) Of those who died of puerperal and postabortal sepsis in the whole study group 8.3% had HIV/AIDS. Of the indirect maternal deaths, 50 (58%) were HIV positive or had AIDS. Conclusion and recommendations: HIV/AIDS contributes to both direct and indirect maternal deaths in Malawi. National strategies to realise MDG5 targets should include addressing the HIV/AIDS epidemic within the entire population as well as scaling up contraceptive uptake and utilisation, especially amongst the most vulnerable groups

Phenotype management: a new approach to habitat restoration

The goal of habitat restoration is to provide environmental conditions that promote the maintenance and growth of target populations. But rarely is it considered how the allocation of resources influences the diversity of phenotypes in these populations. Here we present a framework for considering how habitat restoration can shape the development and expression of phenotypes. We call this approach phenotype management as it entails restoring the resources in a habitat to manage phenotypic diversity. Phenotype management is achieved by manipulating the spatial and temporal distribution of resources to alter the degree of competition among individuals. Differences in competition, in turn, lead to changes in phenotypic and life history expression that affect population parameters including demography and effective population size (Ne). To illustrate how phenotype management can be applied, we explore how resource distributions shape variation in phenotypes in two imperiled fishes, Pacific salmon and desert pupfish. In both examples, modulating male reproductive phenotypes changes the allocation of reproductive success among population members to subsequently affect Ne. These examples further demonstrate that whether to increase or decrease phenotypic diversity depends on the primary conservation pressures faced by the species

Effects of Bisphenol-A and Styrene on Fertilization and Development of the Purple Sea Urchin (Strongylocentrotus purpuratus)

Plastic waste and debris have greatly increased in the marine environment during the past 50 years. Not only do these plastics entangle and get ingested by marine mammals, turtles, and sea birds, but they also leach chemicals, such as bisphenol-A (BPA) and styrene into the aquatic environment. While some of these chemicals are known to be toxic, few studies have examined their effects on broadcast spawning marine invertebrates, specifically at environmentally relevant concentrations. Purple sea urchins, Strongylocentrotus purpuratus, from the central coast of California, were utilized to examine effects of BPA and styrene on fertilization success and early development of resulting embryos. Previous research has demonstrated that BPA and styrene decrease successful fertilization and delay development of sea urchins, though no previous studies have examined effects of continuous chemical treatment on S. purpuratus development. We exposed eggs, sperm, or both to environmentally relevant concentrations of BPA or styrene (100 µg/L, 500 µg/L, and 1000 µg/L) to test the hypothesis that continuous treatment would lead to developmental abnormalities. The greatest effect was observed in pluteus larvae development, as the percentage of normal embryos decreased by as much as 80% in high dose chemical treatments (p