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This article specifies how the setup, or introduction, of cognitively demanding tasks is a crucial phase of middle-grades mathematics instruction. The authors report on an empirical study of 165 middle-grades mathematics teachers' instruction that focused on how they introduced tasks and the relationship between how they introduced tasks and the nature of students' opportunities to learn mathematics in the concluding whole-class discussion.

Background: In 2009, the Institute of Medicine published revised gestational weight gain (GWG) guidelines with changes notable for altered body mass index (BMI) categorization as per World Health Organization criteria and a stated range of recommended gain (11-20 pounds) for obese women. The goal of this study was to evaluate associations between maternal BMI-specific GWG adherence in the context of these new guidelines and risk of small for gestational age (SGA) and large for gestational age (LGA) neonates. Methods: Subjects were a retrospective cohort of 11,203 live birth singletons delivered at 22-44 weeks at a Massachusetts tertiary care center between April 2006 and March 2010. Primary exposure was GWG adherence (inadequate, appropriate, or excessive) based on BMI-specific recommendations. SGA and LGA were defined as <10th and ≥90th percentiles of U.S. population growth curves, respectively. The association between GWG adherence and SGA and LGA was examined in polytomous logistic regression models that estimated adjusted odds ratios (AOR) stratified by prepregnancy weight status, controlling for potential confounders. Results: Before pregnancy, 3.8% of women were underweight, 50.9% were normal weight, 24.6% were overweight, and 20.6% were obese. Seventeen percent had inadequate GWG, and 57.2% had excessive GWG. Neonates were 9.6% SGA and 8.7% LGA. Inadequate GWG was associated with increased odds of SGA (AOR 2.51, 95% confidence interval [CI] 1.31-4.78 for underweight and AOR 1.78, 95% CI 1.42-2.24 for normal weight women) and decreased odds of LGA (AOR 0.5, 95% CI 0.47-0.73 for normal weight and AOR 0.56, 95% CI 0.34-0.90 for obese women). Excessive GWG was associated with decreased odds of SGA (AOR 0.59, 95% CI 0.47-0.73 for normal weight and AOR 0.64, 95% CI 0.47-0.89 for overweight women) and increased odds of LGA (AOR 1.76, 95% CI 1.38-2.24 for normal weight, AOR 2.99, 95% CI 1.92-4.65 for overweight, and AOR 1.55, 95% CI 1.10-2.19 for obese women). Conclusions: Efforts to optimize GWG are essential to reducing the proportion of SGA and LGA neonates, regardless of prepregnancy BMI. [ABSTRACT FROM AUTHOR]

Background: Our objective was to quantify how the 2009 revisions of the 1990 Institute of Medicine (IOM) gestational weight gain (GWG) guidelines change women's body mass index (BMI) categorization and BMI-specific GWG adherence categories. The goal was to identify how provider counseling practices need to change on a population level. Methods: A retrospective review of automated labor and delivery records from a tertiary care hospital in Central Massachusetts was performed. The study cohort included women who delivered singleton, live birth gestations from from April 1, 2006, to September 30, 2009. Records missing weight, height, GWG, gestational age (GA), and/or GA <22 or >43 weeks were excluded. BMI groups and GWG adherence were categorized according to IOM 1990 and 2009 recommendations. Adherence analyses included full-term gestations only. Results: The cohort consisted of 11,688 women, mean age 28.9 (±6.1) years and mean parity 1.0 (±1.1). By 1990 recommendations, 10.1%, 52.5%, 14.1%, and 23.3% gravidas were low weight, normal weight, high weight, and obese; and 19.8%, 33.3%, and 46.9% were undergainers, appropriate gainers, and overgainers, respectively. By 2009 recommendations, 3.9%, 51.3%, 24.5%, and 20.3% gravidas were underweight, normal weight, overweight, and obese, and 16.7%, 30.8%, and 52.6% were undergainers, appropriate gainers, and overgainers, respectively. Differences in categorization by guideline year was significant for BMI category ( p<0.0001) and GWG adherence ( p<0.0001). Compared to 1990 guidelines, 16.7% of women were classified differently using 2009 guidelines, with fewer classified as underweight, normal weight, or obese and more as overweight; 17.1% of 1990 appropriate gainers would be classified as overgainers, given new guidelines. Conclusions: Changes in IOM GWG recommendations alter gravidas' BMI categories and, thus, the recommended GWG. As the amount advised is associated with actual gain, accuracy is paramount. GWG is a modifiable parameter associated with immediate and long-term maternal/neonatal health outcomes, and counseling can have a significant public health impact and should involve BMI determination, followed by BMI-specific GWG recommendations in accordance with current guidelines. [ABSTRACT FROM AUTHOR]

“Classic” cardiovascular drift is characterized by findings of decreasing stroke volume and mean arterial pressure, rising heart rate, and stable cardiac output during sustained constant-load exercise. Recent studies in adults indicate that when dehydration is prevented by fluid intake, this pattern is altered, with no change in stroke volume and progressive rise in cardiac output. This study was designed to examine this influence of hydration in prepubertal subjects and assess the relationship between cardiovascular drift and aerobic drift (changes in VO2). Eight boys (Tanner stage 1, mean age 11.7 ± 0.4 y) cycled at an average of 62.9% ± 3.9% VO2 peak to exhaustion (41.38 ± 6.30 min) in a thermoneutral environment. Rectal temperature rose from 37.6 ± 0.1 °C at rest to 38.1 ± 0.2 °C at end exercise. Between 5 min and end exercise, average heart rate rose by 13.2% and cardiac output rose by 14.9%, systemic vascular resistance fell by 10.5%, and stroke volume remained stable. Increases in cardiac output paralleled those of VO2, with no change in arterial venous oxygen difference. These findings are consistent with the conclusion that cardiovascular drift is a reflection of aerobic drift, a relationship obscured by the superimposed physiological effects of dehydration during sustained constant load. This study also suggests that such patterns are no different in prepubertal boys and young adult men. La dérive cardiovasculaire classique est caractérisée par la diminution du volume d’éjection systolique et de la pression artérielle moyenne, par une augmentation de la fréquence cardiaque et par un débit cardiaque stable au cours d’un effort soutenu d’intensité constante. D’après des récentes études, ce scénario est modifié quand on prévient la déshydratation par un apport de liquide; ainsi, on observe alors une augmentation graduelle du débit cardiaque sans variation du volume d’éjection systolique. Dans cette étude, nous analysons l’effet de l’hydratation chez des sujets prépubères et nous évaluons la relation entre la dérive cardiovasculaire et la dérive aérobie (variation du VO2). Huit garçons (stade 1 de Tanner, âge moyen de 11,7 ± 0,4 ans) pédalent à une intensité équivalent à 62,9 ± 3,9 % du VO2 jusqu’à épuisement (41,38 ± 6,30 min) dans un environnement thermiquement neutre. Du repos à la fin de l’exercice, la température rectale passe de 37,6 ± 0,1 °C à 38,1 ± 0,2 °C. De la cinquième minute à la fin de l’exercice, la fréquence cardiaque augmente de 13,2 % et le débit cardiaque, de 14,9 %; la résistance vasculaire systémique chute de 10,5 % et le volume d’éjection systolique demeure stable. L’augmentation du débit cardiaque suit l’augmentation du VO2 sans variation de la différence artério-veineuse d’oxygène. D’après ces observations, la dérive cardiovasculaire est un reflet de la dérive aérobie, mais cette relation est masquée par les effets physiologiques additionnels de la déshydratation au cours d’un exercice d’intensité constante. De plus, nos observations indiquent que ces phénomènes ne diffèrent pas chez les sujets prépubères et les jeunes adultes masculins. [ABSTRACT FROM AUTHOR]

In an effort to improve access to information about new library materials, the University of Washington (UW) Libraries designed a cost-effective current awareness service to automate the creation and electronic distribution of customized lists of new library materials to user's desktops. The service, named Zephyr, utilizes a customized HyperCard program to serve as the database for user profiles, to conduct searches of databases available on the campus network, and to send out search results via electronic mail. To provide individualized reports, library staff develop profiles of specific search terms by interviewing potential subscribers. Current awareness programs, such as Zephyr, represent a new direction for libraries, one that actively engages users in the libraries service program. Since its inception in 1994, the program has been well-received and has proven to be a valuable component in the UW Libraries efforts to actively disseminate information of interest to library users. [ABSTRACT FROM PUBLISHER]

Objectives: To determine whether alcohol use at time of spinal cord injury (SCI) is more common with cervical injury than with lower levels of spinal injury., Methods: Veterans and nonveterans with SCI were assessed at a Veteran's Affairs Medical Center from 1994 through 2002 and completed a health questionnaire that included information on alcohol use at time of traumatic injury., Results: Of 362 men, 45% had neurologically complete or incomplete cervical injuries. Participants with cervical injury were more likely to have used alcohol when injured (62/162, 38%) compared with participants without cervical injury (45/200, 23%). Adjusting for age at injury and accident type, participants with cervical SCI had an increased relative odds of having used alcohol at injury compared with participants without cervical SCI (2.06, 95% confidence interval = 1.24-3.43)., Conclusion: Alcohol use at time of SCI is a risk factor for cervical injury. This finding is of public health concern and should be included in alcohol educational programs.