Childhood Obesity — What We Can Learn From Existing Data on Societal Trends, Part 1

The number of overweight and obese youth has increased in recent decades, and numerous theories on causes have been proposed. Yet almost no data are available to assess how the lives of children have changed during the “obesity epidemic.” What are children and adolescents now doing with their time that they did not do before? Are they participating less in sports? Watching more television? Doing more homework? Without tracking these broader societal changes, it is difficult to identify the most (and least) promising areas for interventions. This two-part report compiles trend data for several areas. Part 1 discusses trends in time use, homework, and media use; part 2 discusses trends in transportation, physical education, and diet. The main findings of this article are the following: One, the free time of children has substantially declined because of increased time away from home, primarily in school, day care, and after-school programs. Two, participation in organized activities (including sports) has also increased. Three, unstructured playtime has decreased to make room for organized activities. Four, time spent in some sedentary activities like watching television, participating in conversations, or taking part in other passive leisure activities also declined just when obesity became a major concern. Five, increases in homework have not caused decreases in free time, contradicting a common belief in education circles

Information and the Demand for Supplemental Medicare Insurance

While the critical role of imperfect information has become axiomatic in explaining health care market failure, the theory is backed by little empirical evidence. In this paper we use a unique panel data set with explicit measures of information and an educational intervention to investigate the role of imperfect information about health insurance benefits on the demand for supplemental Medicare insurance. We estimate a structural discrete choice model of the demand for supplemental Medicare insurance that allows imperfect information to affect both the mean and the variance of the expected benefits distribution. The empirical specification is a structural panel multinomial probit with an unrestricted variance- covariance, including heteroskedasticity and random effects to control for unobserved heterogeneity. The model is computationally complex and is estimated by simulated maximum likelihood. The empirical results indicate that imperfect information affects the demand for supplemental Medicare insurance by increasing the variance of the expected benefits distribution rather than by systematically shifting the mean of the distribution. We find that the increase in variance due to imperfect information increases the probability of choosing not to purchase supplemental insurance by about 23%. We also found that controlling for unobserved heterogeneity is important. The goodness of fit increased by about 25% and the precision of the estimated effect of information on the variance of the expected benefits distribution improved dramatically.

Comparison of different cover crop mulches and extracts on inhibition of crop and weed growth

Weed suppression of cover crops is a result of competition for light, space, water and nutrients and the release of allelochemicals in the soil. Two laboratory and greenhouse experiments were conducted to analyse biochemical effects of extracts and mulches of Fagopyrum tataricum (L.) Gaertn., Raphanus sativus var. oleiformis Pers. and a cover crop mixture on germination and plant growth of the crop plants maize (Zea mays L.) and sugar beet (Beta vulgaris ssp. vulgaris var. altissima Döll.) and the weeds Chenopodium album L., Matricaria chamomilla L. and Stellaria media (L.) Vill.. In the first experiment, aqueous cover crop extracts were applied on crop and weed seeds in germination assays. Germination rate, mean germination time and root length of crops and weeds were measured. In experiment 2, the influence of cover crop mulch on germination rate and dry weight of the test plants was determined after a period of 21 days. Significant reductions of the root length for all test plants were observed in experiment Additionally, mean germination time was extended for crops and weeds by all cover crops. Germination rate and dry matter of crops and weeds were decreased significantly in experiment 2 compared to the untreated control. Root length, germination rate and mean germination time in germination tests in experiment 1 were found to be correlated with biomass of crops and weeds in experimentThis work reveals the important role of biochemical effects on weed suppression by cover crops.Vergleich verschiedener Zwischenfrucht-Extrakte und Mulch hinsichtlich der Wachstumshemmung von Kulturpflanzen und UnkräuternDie Unterdrückung von Unkräutern durch Zwischenfrüchte kann auf die hohe Konkurrenzkraft um Licht, Raum, Wasser und Nährstoffe, sowie die Abgabe von Allelochemikalien in die Umwelt zurückgeführt werden. Zwei Labor- und Gewächshaus-Versuche wurden durchgeführt, um biochemische Effekte von wässrigen Extrakten und Mulch aus Fagopyrum tataricum (L.) Gaertn., Raphanus sativus var. oleiformis Pers. und einer Zwischenfrucht-Mischung auf die Keimung und das Wachstum von Mais (Zea mays L.), Zuckerrübe (Beta vulgaris ssp. vulgaris var. altissima Döll.) und Unkräutern (Chenopodium album L., Matricaria chamomilla L., Stellaria media (L.) Vill.) zu untersuchen. Im ersten Experiment wurden wässrige Zwischenfrucht-Extrakte in Keimtests auf Kulturpflanzen und Unkräuter appliziert. Die Keimfähigkeit, durchschnittliche Keimdauer und Wurzellänge von Kulturpflanzen und Unkräutern wurden untersucht. In Experiment 2 wurde der Einfluss von Zwischenfrucht-Mulch auf Keimrate und Trockenmasse der Versuchspflanzen untersucht. Die Wurzellänge aller Versuchspflanzen konnte in Experiment 1 signifikant reduziert werden. Zudem wurde die durchschnittliche Keimdauer für Kulturpflanzen und Unkräuter signifikant erhöht. In Experiment 2 wurden Keimfähigkeit und Trockenmasse durch die Aussaat in Zwischenfrucht-Mulch im Vergleich zur Kontrolle signifikant verringert. Wurzellänge, Keimfähigkeit und durchschnittliche Keimdauer aus den Keimtests in Experiment 1 konnten mit der Biomasse der Kulturpflanzen und Unkräuter aus Experiment 2 korreliert werden.  Diese Studie weist auf die bedeutende Rolle der biochemischen Effekte von Zwischenfrüchten zur Unkrautunterdrückung hin

Föderalismus

Der Föderalismus verbindet staatliche Einheit mit territorialer Vielfalt. Die Formen des Föderalismus, die Kompetenzverteilung und die Kooperationsbeziehungen von Bund und Gliedstaaten spiegeln die Balance dieser beiden Ideen wider. Zu unterscheiden sind der duale Förderlismus, der kooperative Föderalismus und die Politikverflechtung. Der Föderalismus ist Ausdruck demkratischer Herrschaft

Производные и интегралы дробных комплексных порядков функций дискретной переменной

Вводится дискретный d-оператор дробного интегродифференцирования комплексных порядков. Рассматривается алгоритм дискретного дифференцирования и дискретного интегрирования функций дискретной переменной

Diet and obesity in Los Angeles County 2007–2012: Is there a measurable effect of the 2008 “Fast-Food Ban”?

We evaluate the impact of “Los Angeles Fast-Food Ban”, a zoning regulation that restricts opening/remodeling of standalone fast-food restaurants in South Los Angeles since 2008. Food retail permits issued after the ban are more often for small food/convenience stores and less often for larger restaurants not part of a chain in South Los Angeles compared to other areas; there are no significant differences in the share of new fast-food chain outlets, other chain restaurants, or large food markets. About 10% of food outlets are new since the regulation, but there is little evidence that the composition has changed differentially across areas. Data from the California Health Interview Survey show that fast-food consumption and overweight/obesity rates have increased from 2007 to 2011/2012 in all areas. The increase in the combined prevalence of overweight and obesity since the ban has been significantly larger in South Los Angeles than elsewhere. A positive development has been a drop in soft drink consumption since 2007, but that drop is of similar magnitude in all areas

Neighborhood Food Outlets, Diet, and Obesity Among California Adults, 2007 and 2009

IntroductionVarying neighborhood definitions may affect research on the association between food environments and diet and weight status. The objective of this study was to examine the association between number and type of neighborhood food outlets and dietary intake and body mass index (BMI) measures among California adults according to the geographic size of a neighborhood or food environment.MethodsWe analyzed data from 97,678 respondents aged 18 years or older from the 2007 and 2009 California Health Interview Survey through multivariable regression models. Outcome variables were BMI, weight status of a BMI of 25.0 or more and a BMI of 30.0 or more, and the number of times per week the following were consumed: fruits, vegetables, sugar-sweetened soft drinks, fried potatoes, and fast food. Explanatory variables were the number of fast-food restaurants, full-service restaurants, convenience stores, small food stores, grocery stores, and large supermarkets within varying distances (0.25 to 3.0 miles) from the survey respondent’s residence. We adopted as a measure of walking distance a Euclidean distance within 1 mile. Control variables included sociodemographic and economic characteristics of respondents and neighborhoods.ResultsFood outlets within walking distance (≤1.0 mile) were not strongly associated with dietary intake, BMI, or probabilities of a BMI of 25.0 or more or a BMI of 30.0 or more. We found significant associations between fast-food outlets and dietary intake and between supermarkets and BMI and probabilities of a BMI of 25.0 or more and a BMI of 30.0 or more for food environments beyond walking distance (>1.0 mile).ConclusionWe found no strong evidence that food outlets near homes are associated with dietary intake or BMI. We replicated some associations reported previously but only for areas that are larger than what typically is considered a neighborhood. A likely reason for the null finding is that shopping patterns are weakly related, if at all, to neighborhoods in the United States because of access to motorized transportation

A simulation framework for the performance assessment of shop-floor control systems

The authors discuss the concept and design criteria for a framework that facilitates the performance assessment of shop-floo control systems. Their basic concept includes a simulation model that emulates the shop floo of a wafer fab, sends information to the control system, and eceives information back from the control system. The shop-floo control system is realized as a separate module that interfaces to the simulator via a data layer that contains the current shop-floo status and the control information generated by the controller. The authors provide detailed information on how the simulation model and shop-floo control system communicate and how each system triggers events in the other system. They show how this framework supports the performance assessment of the shop-floo control system under consideration. They also present a prototype of the framework currently implemented in the course of the SRC/International Sematech FORCe project "Scheduling of Semiconductor Wafer Fabrication Facilities.

Interdependent action of KH domain proteins Krr1 and Dim2 drive the 40S platform assembly

Ribosome biogenesis begins in the nucleolus with the formation of 90S pre-ribosomes, from which pre-40S and pre-60S particles arise that subsequently follow separate maturation pathways. Here, we show how structurally related assembly factors, the KH domain proteins Krr1 and Dim2, participate in ribosome assembly. Initially, Dim2 (Pno1) orchestrates an early step in small subunit biogenesis through its binding to a distinct region of the 90S pre-ribosome. This involves Utp1 of the UTP-B module, and Utp14, an activator of the DEAH-box helicase Dhr1 that catalyzes the removal of U3 snoRNP from the 90S. Following this dismantling reaction, the pre-40S subunit emerges, but Dim2 relocates to the pre-40S platform domain, previously occupied in the 90S by the other KH factor Krr1 through its interaction with Rps14 and the UTP-C module. Our findings show how the structurally related Krr1 and Dim2 can control stepwise ribosome assembly during the 90S-to-pre-40S subunit transition