Childhood disadvantages and the timing of the onset of natural menopause in Latin America and the Caribbean

The aim of this study is to investigate the association of early life factors with the timing of the onset of natural menopause in Costa Rica and Puerto Rico. We use Cox proportional hazard models to estimate the risk of the onset of menopause. Our results suggest that socioeconomic disadvantages, as expressed by difficulties attending school due to economic hardships or parents never living together, increase the risk of the onset of natural menopause among Puerto Rican women. Among Costa Rican women, early life nutrition, estimated using anthropometric measures, is related to the timing of the onset of natural menopause.     

Resolving a Multi-Million Dollar Contract Dispute With a Latin Square

The City of New York negotiated a dispute over the performance of new garbage trucks purchased from a vehicle manufacturer. The dispute concerned the fulfillment of a specification in the purchase contract that the trucks load a minimum full-load of 12.5 tons of household refuse. On behalf of the City, but in cooperation with the manufacturer, the City's Department of Sanitation and consulting statisticians tested fulfillment of the contract specification, employing a Latin Square design for routing trucks. We present the classical analysis using a linear model and analysis of variance. We also show how fixed, mixed, and random effect models are useful in analyzing the results of the test. Finally, we take a Bayesian perspective to demonstrate how the information from the data overcomes the difference between the prior densities of the city and the manufacturer for the load capacities of the trucks to result in much closer posterior densities. This procedure might prove useful in similar negotiations. Supplementary material including the data and R code for computations in the article are available online.     

E-Racing together: How starbucks reshaped and deflected racial conversations on social media

In March 2015, Starbucks introduced its #RaceTogether campaign to encourage patrons to discuss race and ethnicity in global culture. Public reaction to #RaceTogether was largely critical and resulted in Starbucks' abandoning the campaign within a year. Through an analysis of 5000 #RaceTogether tweets, this study examines how users engaged the campaign and each other. This study draws three conclusions. First, most #RaceTogether posts featured extremist and racist positions. Second, #RaceTogether posts deflected race conversations and critiqued the organizations role in national racial discourses. Finally, posts in the digital space critiqued Starbucks as a location for inter-racial dialogue because of brand perception.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.     

How beliefs about substance use differ by socio-demographic characteristics,individual experiences,and neighborhood environments among urban adolescents

In this article, we tested a series of Item Response Theory (IRT) models to examine the individual and neighborhood variation in perceived risk along dimensions of substance use (alcohol, marijuana, and hard drugs) and usage patterns (light/experimental use, moderate use, heavy/regular use). Data were gathered from 2266 adolescents aged 9, 12, and 15 residing in 79 Chicago neighborhoods. Developmental patterns for age and amount of use were observed whereby older respondents rated alcohol and marijuana as less harmful compared to the younger respondents, but rated hard drugs as more harmful. Risk perceptions were found to be more closely tied to one's direct experience with drugs rather than a general constellation of beliefs. Neighborhood variation in risk perceptions was also observed for hard drugs and three patterns of use, controlling for characteristics of individual residents. Neighborhoods did not vary in risk perceptions toward alcohol use. Individual-level factors rather than characteristics of the neighborhoods explained the observed neighborhood variation in perceptions toward marijuana use. These findings illustrate the complex links between individual and contextual factors in the development of beliefs about the health risks associated with substance use.     

Examining the Effects of Feedback Accuracy and Timing on Skill Acquisition

ABSTRACT

Feedback involves providing information about past performance and indicating how to improve future performance. Although the literature contains numerous examples of feedback as an effective method for improving performance across a range of organizational settings, much remains unknown about the specifics of how feedback acts to change behavior. This study evaluated the combined effects of feedback accuracy (100%, 80%, 20%) and timing (feedback following each trial or after a block of 25 trials) on skill acquisition in undergraduate students when presented with a computerized match-to-sample task that required participants to learn the names of shapes. Results reveal that feedback accuracy had a significantly greater effect on performance than the timing of the feedback.     

The Role of Attachment Behaviors in the Link between Relationship Satisfaction and Depression in Clinical Couples: Implications for Clinical Practice

Using dyadic, clinical data from 104 couples in committed relationships, the purpose of this study was to determine whether relationship satisfaction was associated with depression through perceived partner attachment behaviors—accessibility, responsiveness, and engagement—for both men and women. We found that one's satisfaction in the relationship was the lens through which they viewed their partner's attachment behaviors and—women's relationship satisfaction was the lens through which her male partner viewed her attachment behaviors. Finally, women's relationship satisfaction is associated with both individuals' depression through her perceived partner's accessibility, responsiveness, and engagement. The findings from this study are important because they provide clinically relevant and mutable constructs in which clinicians can intervene at an attachment level in distressed marriages with depressed partners.     

Obesity and excess mortality among the elderly in the United States and Mexico

Increasing levels of obesity could compromise future gains in life expectancy in low-and high-income countries. Although excess mortality associated with obesity and, more generally, higher levels of body mass index (BMI) have been investigated in the United States, there is little research about the impact of obesity on mortality in Latin American countries, where very the rapid rate of growth of prevalence of obesity and overweight occur jointly with poor socioeconomic conditions. The aim of this article is to assess the magnitude of excess mortality due to obesity and overweight in Mexico and the United States. For this purpose, we take advantage of two comparable data sets: the Health and Retirement Study 2000 and 2004 for the United States, and the Mexican Health and Aging Study 2001 and 2003 for Mexico. We find higher excess mortality risks among obese and overweight individuals aged 60 and older in Mexico than in the United States. Yet, when analyzing excess mortality among different socioeconomic strata, we observe greater gaps by education in the United States than in Mexico. We also find that although the probability of experiencing obesity-related chronic diseases among individuals with high BMI is larger for the U. S. elderly, the relative risk of dying conditional on experiencing these diseases is higher in Mexico.     

磁控溅射制备Ti-O-N选择性太阳能吸收涂层

太阳能集热器是太阳能热水器的核心部件,平板集热器可以作为建筑材料与建筑完美融合,满足城市对太阳能的利用与建筑一体化的要求.本论文用中频磁控溅射技术制备用于平板集热器的Ti-O-N选择性吸收涂层.用XRD、SEM及红外反射测试研究工艺参数对吸收涂层结晶质量、形貌及反射率的影响.设置镀膜过程中气压分别为0.8Pa、1.2Pa和2.0Pa而其他参数不变,制备出不同气压条件下的Ti-O-N选择性吸收涂层,通过分析样品的表面形貌及红外反射率来研究镀膜过程中气压对涂层质量的影响.实验表明,气压越低,所镀的薄膜颗粒越致密均匀,薄膜表面越光滑,薄膜的集热效率越高,即涂层的质量越好.