Impact-parameter dependence of K-shell ionisation in slow collisioons of near-symmetric relitivistic atoms

Abstract. The total K vacancy production probability of both collision partners in a heavy-ion-atom collision is calculated, assuming that two processes contribute, a single-collision process where 2po and 2pa vacancies are created by direct ionisation of the united atom and subsequently redistributed, and a double-collision process where a 2pa vacancy is created in the first collision and partially transferred in the second. The model used for the single-collision process is valid for slow collisions between partners of a combined charge greater than 70. Numerical results are presented for the (I, I) and (I, Ag) systems and show improved agreement with recent experiments. 1

Street children: our health and coping strategies when we are sick

Millions of street children in both developed and developing countries are left to survive on their own. They are ill-treated, half-starved, ruthlessly abused, exposed to the elements of nature, socially deprived and abandoned and denied affection, education and assistance. Street children often arrive in this dead end with poor health generally. This accrual, in combination with the inconsiderate circumstances of street life, soon contribute to the child's lowered immunity, morbidity, ill health and eventually, the child's exposure to health problems. Street children are one of the new categories of social actors resulting from the rapid urbanisation of cities of the South. Among the numerous problems they have to face daily, there are also obstacles related to disease and access to healthcare. This was a qualitative study conducted from late October to November 2014, on the streets and in market places of Accra. The sample size was fifteen (15) street children selected using a non-random snowball sampling technique.  The findings on the diseases that the street children experience by living and working in the streets of Accra such as injuries and minor accidents could be due to the nature of their work and the environment (hawking goods on the busy streets of the city and carrying heavy loads. The findings of the study indicate that the health conditions of working street children are miserable and majority of the available health services are out of reach of street children and there are multiple obstacles faced by street children in accessing health care services. Various strategies should be applied in bringing about a social change, a major one being “Empowerment”. This can be achieved through activities aimed at providing better economic opportunities through improved vocational and other skills leading to ‘economic empowerment’ of the child and improved savings skills. Keywords: street children, health, coping strategies, city, Accr

Good for Parents but Bad for Wives: Migration as a Contested Model of Success in Contemporary Ghana

This paper contributes to the literature that critiques the New Economics of Labour Migrations’ perspectives on the motivations for migration. It uses both a gender and generation lens to explore the multiple meanings that parents and wives make of the migration of Ghanaian young men to Libya and beyond. The paper draws on a range of qualitative methods – interviews, focus group discussions, river of life approaches and ethnography – conducted in three phases (April 2018, July/August 2018 and January 2019) of research to make its arguments. It argues that parents share a view of migration which is more in line with the New Economics of Labour Migration perspective. This view is exemplified in the traditional Akan conception of an Opanyin, a successful adult (Miescher, 2005), which focuses on economic success (taking good care of one’s family, providing one’s family with a home). Wives, however, hold an alternative view, one that the New Economics of Labour Migration perspective fails to capture. For wives, their conception of a successful male adult is informed by the changing socio-cultural context and focuses on affective ties (physical proximity, day to day care and sexual ties). Thus, while parents are generally supportive of young male migration, wives generally disapprove of migration.DFI

Testosterone Amplifies the Negative Valence of an Agonistic Gestural Display by Exploiting Receiver Perceptual Bias

Many animals communicate by performing elaborate displays that are incredibly extravagant and wildly bizarre. So, how do these displays evolve? One idea is that innate sensory biases arbitrarily favour the emergence of certain display traits over others, leading to the design of an unusual display. Here, we study how physiological factors associated with signal production influence this process, a topic that has received almost no attention. We focus on a tropical frog, whose males compete for access to females by performing an elaborate waving display. Our results show that sex hormones like testosterone regulate specific display gestures that exploit a highly conserved perceptual system, evolved originally to detect \u27dangerous\u27 stimuli in the environment. Accordingly, testosterone makes certain gestures likely to appear more perilous to rivals during combat. This suggests that hormone action can interact with effects of sensory bias to create an evolutionary optimum that guides how display exaggeration unfolds

Ethnic Minority Children’s Active Commuting to School and Association with Physical Activity and Pedestrian Safety Behaviors

Background: Children\u27s active commuting to school, i.e. walking or cycling to school, was associated with greater moderate-to-vigorous physical activity, although studies among ethnic minorities are sparse. Objectives: Among a low-income, ethnic minority sample of fourth grade students from eight public schools, we examined (1) correlates of active commuting to school and (2) the relationship between active commuting to school and moderate-to-vigorous physical activity. Methods: We conducted a cross-sectional analysis of baseline measurements from a sample of participants (n=149) aged 9-12 years from a walk to school intervention study in Houston, Texas. The primary outcome was the weekly rate of active commuting to school. Daily moderate-to-vigorous physical activity, measured by accelerometers, was a secondary outcome. Child self-efficacy (alpha=0.75), parent self-efficacy (alpha=0.88), and parent outcome expectations (alpha=0.78) were independent variables. Participant characteristics (age, gender, race/ethnicity, distance from home to school, acculturation, and BMI percentile) were independent sociodemographic variables. We used mixed-model regression analyses to account for clustering by school and a stepwise procedure with backward elimination of non-significant interactions and covariates to identify significant moderators and predictors. School-level observations of student pedestrians were assessed and compared using chi-square tests of independence. Results: Among our sample, which was 61.7% Latino, the overall rate of active commuting to school was 43%. In the mixed model for active commuting to school, parent self-efficacy (std. beta = 0.18, p=0.018) and age (std. beta = 0.18, p=0.018) were positively related. Latino students had lower rates of active commuting to school than non-Latinos ( 16.5%, p=0.040). Distance from home to school was inversely related to active commuting to school (std. beta = 0.29, p\u3c0.001). In the mixed model for moderate-to-vigorous physical activity, active commuting to school was positively associated (std. beta = 0.31, p \u3c0.001). Among the Latino subsample, child acculturation was negatively associated with active commuting to school (std. beta = -0.23, p=0.01). With regard to school-level pedestrian safety observations, 37% of students stopped at the curb and 2.6% looked left-right-left before crossing the street. Conclusion: Although still below national goals, the rate of active commuting was relatively high, while the rate of some pedestrian safety behaviors was low among this low-income, ethnic minority population. Programs and policies to encourage safe active commuting to school are warranted and should consider the influence of parents, acculturation, and ethnicity

Insight into the Evolution of Anuran Foot Flag Displays: A Comparative Study of Color and Kinematics

Understanding how complex animal displays evolve is a major goal of evolutionary organismal biology. Here, we study this topic by comparing convergently evolved gestural displays in two unrelated species of frog (Bornean Rock Frog, Staurois parvus, and Kottigehara Dancing Frog, Micrixalus kottigeharensis). This behavior, known as a foot flag, is produced when a male ?waves\u27 his hindlimb at another male during bouts of competition for access to mates. We assess patterns of variation in the color of frog feet and the kinematics of the display itself to help pinpoint similarities and differences of the visual signal elements. We find clear species differences in the color of foot webbing, which is broadcast to receivers during specific phases of the display. Analyses of foot-trajectory duration and geometry also reveal clear species differences in display speed and shape - S. parvus generates a faster and more circular visual signal, while M. kottigeharensis generates a much slower and more elliptical one. These data are consistent with the notion that color, speed, and shape likely encode species identity. However, we also found that foot flag speed shows significant among-individual variation, particularly the phase of the display in which foot webbings are visible. This result is consistent with the idea that frogs alter temporal signal components, which may showcase individual condition, quality, or motivation. Overall, our comparative study helps elucidate the variability of foot flagging behavior in a manner that informs how we understand the design principles that underlie its function as a signal in intraspecific communication

Etiología del síndrome febril agudo en niños de 1 mes a 5 años hospitalizados en el Servicio de Urgencias del Hospital Universitario Hernando Moncaleano Perdomo de Neiva

Fever in children causes many consultations with health professionals involving primarily children under 5 years of age and often with unknown etiology for practitioners and caregivers. Objective. To determine acute fever síndrome in children of 1 month to 5 years of age attended at the emergency department at Hernando Moncaleano Perdomo University Hospital in Neiva, between July 2012 and June 2013. Materials and methods. It was carried out a prospective, descriptive study at Hernando Moncaleano Perdomo University Hospital in Neiva, from July 2012 to June 2013, in children whose age ranged from 1 month to 5 years of age, admitted at the pediatric emergency unit.  These children underwent lab tests, including dengue rapid test, (lgG/lgM + NS1 Ag) and Elisa IgM PANBIO®, respiratory viral panel and rotating-test. Data were stored in Excel spreadsheet and analyzed using SPSS version 20 program. Results. From the total, 650 children were included. They were divided into two groups; one with respiratory symptoms (total 261) and the other without respiratory symptoms (total 389), distributed on a frequency basis as follows: respiratory tract infections, dengue, acute diarrheic disease, urinary tract infection, skin disease, and soft tissues, and rash diseases. Conclusions. Viral infections are the main etiology of acute fever syndrome in children under 5 years of age.          La fiebre en los niños es causa de muchas consultas con profesionales en salud comprometiendo principalmente a menores de 5 años y frecuentemente con etiología desconocida por profesionales y cuidadores. Objetivo. Determinar la etiología del síndrome febril agudo en niños de 1 mes a 5 años atendidos en el servicio de urgencias del Hospital Universitario Hernando Moncaleano Perdomo de Neiva entre julio de 2012 y junio de 2013. Materiales y métodos. Se llevó a cabo un estudio descriptivo, prospectivo en el Hospital Universitario Hernando Moncaleano Perdomo de Neiva, durante el periodo comprendido entre Julio de 2012 a Junio de 2013, en niños de 1 mes a 5 años, que ingresaron al servicio de urgencias pediátricas, a quienes se realizaron pruebas de laboratorio necesarias, incluyendoprueba rápida dengue, (lgG/lgM + NS1 Ag) y Elisa IgM PANBIO®, panel viral respiratorio y rota-test. Los datos fueron almacenados en hoja de cálculo de Excel, analizadosen el programa SPSS versión 20. Resultados. Del total de niños, 650 fueron incluidos. Se dividieron en dos grupos, uno con síntomas respiratorios (total 261) y otro sin síntomas respiratorios (total 389), distribuidos por orden en frecuencia así: Infecciones del tracto respiratorio, primer lugar, seguido por dengue, enfermedad diarreica aguda, infección tracto urinario, infecciones de piel y tejidos blandos y enfermedades exantemáticas. Conclusiones. Las infecciones virales se constituyen como la principal etiología del síndrome febril agudo en niños menores de 5 años

Robots facilitate human language production

Despite recent developments in integrating autonomous and human-like robots into many aspects of everyday life, social interactions with robots are still a challenge. Here, we focus on a central tool for social interaction: verbal communication. We assess the extent to which humans co-represent (simulate and predict) a robot’s verbal actions. During a joint picture naming task, participants took turns in naming objects together with a social robot (Pepper, Softbank Robotics). Previous findings using this task with human partners revealed internal simulations on behalf of the partner down to the level of selecting words from the mental lexicon, reflected in partner-elicited inhibitory effects on subsequent naming. Here, with the robot, the partner-elicited inhibitory effects were not observed. Instead, naming was facilitated, as revealed by faster naming of word categories co-named with the robot. This facilitation suggests that robots, unlike humans, are not simulated down to the level of lexical selection. Instead, a robot’s speaking appears to be simulated at the initial level of language production where the meaning of the verbal message is generated, resulting in facilitated language production due to conceptual priming. We conclude that robots facilitate core conceptualization processes when humans transform thoughts to language during speaking.Peer Reviewe

Photochemical oxidation of oxalate in Pu-238 process streams

For over forty years, NASA has relied on plutonium-238 in Radioisotope Thermoelectric Generator (RTG) units and Radioisotope Heater Units ( W s ) to provide power and heat for many space missions including Transit, Pioneer, Viking, Voyager, Galileo, Ulysses and Cassini. RHUs provide heat to keep key components warm in extremely cold environments found on planets, moons, or in deep space. RTGs convert heat generated from the radioactive decay of plutonium-238 into electricity using a themocouple, Plutonium-238 has proven to be an excellent heat source far deep space missions because of its high thermal power density, useful lifetime, minimal shielding requirements, and oxide stability