Spread the Word Nevada

Spread the Word addresses the issue of literacy among children, in particular those who come from low income households.https://digitalscholarship.unlv.edu/educ_sys_202/1075/thumbnail.jp

A recipe for an unpredictable random number generator

In this work we present a model for computation of random processes in digital computers which solves the problem of periodic sequences and hidden errors produced by correlations. We show that systems with non-invertible non-linearities can produce unpredictable sequences of independent random numbers. We illustrate our result with some numerical calculations related with random walks simulations.Comment: 8 pages, 5 figures, Proceedings Mochima spring school in theoretial physic

Understanding the illicit drug distribution in England: a data-centric approach to the County Lines Model

The County Lines Model (CLM) is a relatively new illicit drugs distribution method found in Great Britain. The CLM has brought modern slavery and public health issues, while challenging the law-enforcement capacity to act, as coordination between different local police forces is necessary. Our objective is to understand the territorial logic behind the line operators when establishing a connection between two places. We use three different spatial models (gravity, radiation and retail models), as each one of them understands flow from place i to j in a different way. Using public data from the Metropolitan Police of London, we train and cross-validate the models to understand which of the different physical and socio-demographic variables are considered when establishing a connection. We analyse hospital admissions by drugs, disposable household income, police presence and knife crime events, in addition to the population of a particular place and the distance and travel times between two different. Our results show that knife crime events and hospital admissions by misuse of drugs are the most important variables. We also find that London operators distribute to the territory known as the "South" of England, as negligible presence of them is observed outside of it

Do Physical Activity, Diet and Sex Modify the Association Between Neurotrophin Single Nucleotide Polymorphisms and Insomnia?

Sleep disturbance is common in older adults at prevalence rates ranging between 30 - 50% in the United States. Neurotrophins such as brain-derived neurotrophic factor (BDNF), play a role in sleep (Bachmann et al., 2012) as do lifestyle factors such as physical activity (Dolezal et al., 2017) and diet. This study examined the associations of selected single nucleotide polymorphisms or SNPs related to BDNF or its receptors and lifestyle factors of physical activity and diet, as well as their interactions on the risk for sleep disturbance in older adult males and females. This thesis examined existing data from the Cache County Study on Memory and Aging (CCSMA), a longitudinal, population study of 5,092 individuals aged 65 years and older residing in Cache County, Utah. The results suggest that SNPs related to BDNF or its receptors were not related to sleep problems in either males or females. In males, increased physical activity reduced the likelihood of experiencing sleep disturbances, while unexpectedly, greater adherence to the Mediterranean diet slightly increased the likelihood of reporting sleep problems. In females, the SNPs and lifestyle choices did not appear to have any relationship with sleep disturbance. However, an interaction between the BDNF gene Val66Met and physical activity showed a trend. Specifically, females with the minor and less common allele who reported sedentary-to-light physical activity exhibited a 45% increase in risk of sleep disturbance compared to those who reported moderate-to-vigorous physical activity. Overall, this study suggests that SNPs related to BDNF or its receptors had no significant association with sleep disturbance, but that some effects may be specific to males or females. Increasing physical activity may be beneficial for males with sleep disturbance as well as for females, but for the latter, only for a certain BDNF genetic profile. Future studies may wish to further explore sex-dependent associations between genes and lifestyle factors in improving sleep disturbance in older adults

Un accidente de trabajo atípico

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La vida y el sol: La inevitable tendencia al desorden y la (aparente) paradoja de la vida

Los seres vivos toman materia simple de su entorno y la organizan construyendo sistemas altamente complejos, lo que parece contradecir la natural tendencia al desorden del universo conocida como entropía. ¿Cómo logran los seres vivos construirse y perpetuarse contra esta tendencia a la degradación? La clave está en su habilidad para utilizar la energía proveniente del Sol para imponer orden a la materia que los constituye.Fil: Leonardo González Galli. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación e Investigación en Enseñanza de las Ciencias; Argentin

Separação da camada limite turbulenta em Fluidos não-Newtonianos tipo lei de potência

The present study presents an experimental and theoretical analysis of the behavior of turbulent flows of Newtonian and non-Newtonian power law fluids subjected to and adverse pressure gradient. Although the study of this phenomenon is a topic of research of great industrial importance, models and experimental data that describe it are limited, thus, the purpose of the work is to contribute to a better understanding of the mechanisms that govern the general behavior of this type of flows. Within this context, extensive measurement campaigns were conducted using, at the beginning, the particle image velocimetry technique to characterize and obtain data of the global behavior of the flows. Later, in order to understand the boundary layer structure, particularly in the region adjacent to the wall, measurements with laser Doppler anemometry were performed at several stations, located before and during separation. To perform the tests, a two-dimensional water tunnel was designed and built with a test section made of transparent acrylic. Three geometries were analyzed: the first, a backward facing step with an aspect ratio of 2: 1 and finally two smooth ramp with slopes of θ = 15◦ e 30◦ , respectively. For the non-Newtonian case, a sodium Carboxymethyl cellulose aqueous solution was used, which, after some rheometer tests, showed a totally shear thinning behavior. The implemented procedures contributed to obtaining new experimental data for the characterization of this phenomenon, introducing a new theory in the study of the separation analyzing, besides the shear stress at the wall, the influence of the turbulence and the Reynolds number in the position of the point of separation and re-attachment of the turbulent boundary layer.O presente estudo apresenta uma análise teórica experimental do comportamento de escoamentos turbulentos de fluidos newtonianos e não newtonianos tipo lei de potencia submetidos a um gradiente adverso de pressão. Embora o estudo deste fenômeno constitui um tema de pesquisa de grande importância industrial, modelos e dados experimentais que o descrevem são limitados, isto posto, o propósito do trabalho é contribuir para uma melhor compreensão dos mecanismos que regem o comportamento geral deste tipo de escoamentos. Dentro deste contexto conduziram-se extensas campanhas de medição empregando a princípio, a técnica de velocimetria por imagem de partículas para caracterizar e obter dados do comportamento global dos escoamentos. Posteriormente, e com o intuito de debelar a estrutura da camada limite, particularmente na região adjacente a parede, medições com anemometria laser Doppler foram realizadas em várias estações, localizadas antes e durante a separação. Para realizar os testes foi projetado e construído, um túnel d’Água bidimensional, com uma seção de teste feita de acrílico transparente. Três geometrias foram analisadas: A primeira, um degrau com uma com uma razão de aspecto de 2: 1 e a seguir duas rampas suaves com inclinação de 15 e 30 graus, respectivamente. Para o caso não newtoniano, foi usada uma solução aquosa de Carboximetilcelulose de sódio, o qual após ensaios em reômetro apesentou um comportamento totalmente reofluidificante. Os procedimentos implementados contribuíram na obtenção de novos dados experimentais para a caracterização deste fenômeno, introduzindo uma nova teoria no estudo da separação analisando além da tensão cisalhante na parede, a influência da turbulência e do numero de Reynolds na posição do ponto de separação e recolamento da camada limite turbulenta

Lack of Association between BRAF Mutation and MAPK ERK Activation in Melanocytic Nevi

The mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase signaling pathway can be activated through mutations of V-RAF murine sarcoma viral oncogene homolog B1 (BRAF) oncogene, frequently found in melanoma (60%), common nevi (CN) (73–82%), and atypical nevi (AN) (52–80%). MAPK activation has been reported between 0 and 22% in nevi, and 86% of primary melanoma, without any knowledge of BRAF mutational status. We studied the correlation of MAPK activation status, BRAF mutation, and B-Raf expression in CN, AN, and melanoma. Using immunohistochemistry, phosphorylated (active) MAPK and B-Raf expression was studied in 24 CN, 21 AN, and 26 primary cutaneous melanomas (PM). BRAF mutations at codon 600 were assessed by PCR-RFLP. Active MAPK was detected in 29% of CN, 48% of AN, and 85% of PM. BRAF mutation was found in 67% of CN, 62% of AN, and 58% of PM. In all, 23% of CN, 54% of AN, and 93% of PM with BRAF mutation have activated MAPK. All lesions expressed B-Raf. BRAF mutation does not seem to be sufficient to produce MAPK activation in melanocytic nevi, and it is suggested that other events are needed to induce MAPK activation, that is, B-Raf overexpression, inhibition of MAPK phosphatases, or suppression of RAF kinase inhibitors