Analysis of hydrogen fueling, recycling, and confinement at Wendelstein 7-X via a single-reservoir particle balance

A single-reservoir particle balance for the main plasma species hydrogen has been established for Wendelstein 7-X (W7-X). This has enabled the quantitative characterization of the particle sources in the standard island divertor configuration for the first time. Findings from attached scenarios with two different island sizes with a boronized wall and turbo molecular pumping are presented. Fueling efficiencies, particle flows and source locations were measured and used to infer the total particle confinement time $\tau_{\rm{p}}$. Perturbative gas injection experiments served to measure the effective particle confinement time $\tau_{\rm{p}}^*$. Combining both confinement times provides access to the global recycling coefficient $\bar{R}$. Hydrogen particle inventories have been addressed and the knowledge of particle sources and sinks reveals the core fueling distribution and provides insight into the capability of the magnetic islands to control exhaust features. Measurements of hydrogen fueling efficiencies were sensitive to the precise fueling location and measured between 12~\% and 31~\% with the recycling fueling at the strike line modeled at only 6~\%, due to much higher densities. 15~\% of the total \SI{5.2E+22}{a/s} recycling flow ionizes far away from the recycling surfaces in the main chamber. It was shown that 60~\% of recycled particles ionize above the horizontal and 18~\% above the vertical divertor target, while the remainder of the recycling flow ionizes above the baffle (7~\%). Combining these source terms with their individual fueling efficiencies resolves the core fueling distribution. Due to the higher fueling efficiency in the main chamber, up to 51~\% of the total \SI{5.1E+21}{1/s} core fueling particles are entering the confined plasma from the main chamber. $\tau_{\rm{p}}$ values in the range of 260 ms were extracted for these discharges. Together with $\tau_{\rm{p}}$, the global recycling coefficient $\bar{R}$ was resolved for every $\tau_{\rm{p}}^*$ measurement and a typical value close to unity was obtained. An increase of the island size, resulted in no change of $\tau_{\rm{p}}$, but doubled $\tau_{\rm{p}}^*$, indicating the feasibility of the control coils as an actuator to control exhaust features without affecting core confinement properties.

Impacto de la COVID-19 en la práctica deportiva de personas participantes en eventos deportivos de carrera a pie y ciclismo en España y Portugal (The impact of COVID-19 on physical activity on people who participate on running and cycling sporting events

Es objeto de este artículo analizar el efecto de la COVID-19 en la práctica deportiva de personas participantes en eventos deportivos de carrera a pie y ciclismo en España y Portugal. Se consideró la situación de práctica deportiva en España y Portugal previa a la irrupción de la COVID-19, como ambos Gobiernos legislan para proteger a los ciudadanos de la pandemia y se analizan las consecuencias de éstas. Se realizó una investigación descriptiva mediante el uso de cuestionario (N=2696) y análisis estadístico descriptivo según características y distribución (prueba de la normalidad) de las diferentes variables: frecuencias, valores medios, máximas y mínimas, mediana e IQR. De los resultados obtenidos se puede destacar: a) la casi plena coincidencia entre estados del perfil genérico de los practicantes; el orden por porcentaje de las variables, e incluso, los porcentajes de cada variable para cuatro de las cinco dimensiones analizadas; b) la dimensión que más difiere fue como se adaptaron durante la fase de confinamiento las personas practicantes en España y Portugal, y c) que en todo momento las personas encuestadas percibieron que las adaptaciones serían pasajeras y era cuestión de algunos meses que se volviera a la normalidad. Estos datos permiten entender el efecto que la pandemia de la COVID-19 tuvo en la práctica deportiva y de participantes de eventos deportivos en el medio natural en España y Portugal. Abstract. The aim of this article is to analyze the impact of COVID-19 on physical activity on people who participate on running and cycling sporting events people in Spain and Portugal. It was considered The situation of sports practice in Spain and Portugal prior to the outbreak of COVID-19, as both governments legislate to protect citizens from the pandemic and it was analyzed the consequences of these acts. A descriptive investigation was carried out using a questionnaire (N=2696) and descriptive statistical analysis according to characteristics and distribution (test of normality) of different variables: frequencies, average, maximum and minimum values, median and IQR. From the results, the following can be highlighted: a) almost complete coincidence between both countries, of the generic profile of the practitioners; the order, by percentage, of the variables, and even the percentages of each variable for four of the five dimensions analyzed; b) the dimension that differs the most is how practitioners in Spain and Portugal adapted during the confinement time, and c) at all times the respondents perceived that the adaptations would be temporary and it was a matter of a few months before they returned to the normality. These data allow to understand the effect of COVID-19 pandemic had on physical activity on people who participate on sporting events in the natural environment in Spain and Portugal.

Likelihood of obtaining tender meat from confined calf

The objective was to evaluate the main factors that influence the shear strength of meat from confined steers and the probability of obtaining soft meat. For this purpose, we evaluated the literature on carcass and/or meat of beef steers in Brazil published between January 1999 and April 2019 and extracted the content from three sections for analysis: materials and methods, results, and discussion. Pearson’s correlation was used to analyze the data, and the stepwise statistic was used to determine the proportion of the synchronized effect of variables on shear force. For determining the probability of tenderness, meat with a shear force lower than 4.6 kgf/cm3 was classified as soft; meat with a higher sheer force was classified as hard. Following the classification, logistic regression analysis and odds ratio test were performed. The factors of study location, the proportion of zebu background in the genome, finishing weight, the percentage of concentrate in the diet, and finishing period and meat marbling explained 62.45% of the variability in the shear strength of beef. The following strategies were found to increase the chances of effectively obtaining soft meat from confined steers: starting the termination phase early even in animals with lower weights, prolonging the confinement time, increasing concentrate percentage in the diet, and a higher marbling degree. It is possible to estimate a large proportion of shear force variability using the production variables (ante-mortem), and the process can be adjusted accordingly to considerable increase the possibility of obtaining soft meat.