ORIGO stepping stones common core mathematics Grade 5 practice book

ORIGO Stepping Stones is written and developed by a team of experts to provide teachers with a world-class elementary math program. Our expert team of authors and consultants are utilizing all available educational research to create a unique program that has never before been available to teachers. The full color Student Practice Book provides practice pages that support previous and current lessons.

High and low mammographic density human breast tissues maintain histological differential in murine tissue engineering chambers

Mammographic density (MD) is the area of breast tissue that appears radiologically white on mammography. Although high MD is a strong risk factor for breast cancer, independent of BRCA1/2 mutation status, the molecular basis of high MD and its associated breast cancer risk is poorly understood. MD studies will benefit from an animal model, where hormonal, gene and drug perturbations on MD can be measured in a preclinical context. High and low MD tissues were selectively sampled by stereotactic biopsy from operative specimens of high-risk women undergoing prophylactic mastectomy. The high and low MD tissues were transferred into separate vascularised biochambers in the groins of SCID mice. Chamber material was harvested after 6 weeks for histological analyses and immunohistochemistry for cytokeratins, vimentin and a human-specific mitochondrial antigen. Within-individual analysis was performed in replicate mice, eliminating confounding by age, body mass index and process-related factors, and comparisons were made to the parental human tissue. Maintenance of differential MD post-propagation was assessed radiographically. Immunohistochemical staining confirmed the preservation of human glandular and stromal components in the murine biochambers, with maintenance of radiographic MD differential. Propagated high MD regions had higher stromal (p = 0.0002) and lower adipose (p = 0.0006) composition, reflecting the findings in the original human breast tissue, although glands appeared small and non-complex in both high and low MD groups. No significant differences were observed in glandular area (p = 0.4) or count (p = 0.4) between high and low MD biochamber tissues. Human mammary glandular and stromal tissues were viably maintained in murine biochambers, with preservation of differential radiographic density and histological features. Our study provides a murine model for future studies into the biomolecular basis of MD as a risk factor for breast cancer.

Validity of the previous day physical activity recall (PDPAR) in fifth-grade children

This study evaluated the validity of the Previous Day Physical Activity Recall (PDPAR) self-report instrument in quantifying after-school physical activity behavior in fifth-grade children. Thirty-eight fifth-grade students (mean age, 10.8 +/- 0.1; 52.6% female; 26.3% African American) from two urban elementary schools completed the PDPAR after wearing a CSA WAM 7164 accelerometer for a day. The mean within-subject correlation between self-reported MET level and total counts for each 30-min block was 0.57 (95% C.I., 0.51-0.62). Self-reported mean MET level during the after-school period and the number of 30-min blocks with activity rated at greater than or equal to 6 METs were significantly correlated with the CSA outcome variables. Validity coefficients for these variables ranged from 0.35 to 0.43 (p <.05). Correlations between the number of 30-min blocks with activity rated at greater than or equal to 3 METs and the CSA variables were positive but failed to reach statistical significance (r = 0.19-0.23). The PDPAR provides moderately valid estimates of relative participation in vigorous activity and mean MET level in fifth-grade children. Caution should be exercised when using the PDPAR to quantify moderate physical activity in preadolescent children.

A prospective study of the determinants of physical activity in rural fifth-grade children

Background Understanding the factors that influence physical activity behavior is important in the design of intervention programs targeted at youth. Methods A prospective study design was used to identify the predictors of vigorous physical activity (VPA) (greater than or equal to 6 METs) and moderate and vigorous physical activity (MVPA) (greater than or equal to 3 METs) among 202 rural, predominantly African-American children. Selected social-cognitive determinants of physical activity were assessed via questionnaire in the fifth grade. Participation in VPA and MVPA was assessed via the previous day physical activity recall 1 year later in the sixth grade. Results For girls, participation in community sports, self-efficacy in overcoming barriers, enjoyment of school physical education, race (white > black), and perception of mother's activity level (active vs inactive) were significant predictors of VPA. For MVPA, participation in community sports and self-efficacy in overcoming barriers were significant predictors. For boys, self-efficacy in overcoming barriers was the only significant predictor of VPA, while beliefs regarding activity outcomes and participation in community sports were significant predictors of MVPA. Conclusion Social-cognitive constructs such as physical activity self-efficacy, access to community physical activity outlets, and positive beliefs regarding physical activity outcomes are important predictors of future physical activity behavior among rural, predominantly African-American children.

Gender differences in physical activity and determinants of physical activity in rural fifth grade children

This study determined if gender differences in physical activity could be accounted for by differences in selected social-cognitive determinants of activity behavior. Some 334 fifth grade, predominantly African-American students provided information regarding after-school physical activity and the hypothesized determinants of activity behavior. Boys reported significantly greater participation in vigorous (greater than or equal to 6 METs) and in moderate to vigorous (greater than or equal to 4 METs). Relative to girls, boys demonstrated higher levels of physical fitness, greater self-efficacy in overcoming barriers to physical activity, greater amounts of television watching, and higher levels of participation in community sports and physical activity organizations. When mean physical activity scores for girls and boys were adjusted for the effects of these determinant variables, the significant gender difference in physical activity remained. However, adjustment for self-efficacy in overcoming barriers and community sports reduced the gender gap by 5% and 7%, respectively. In contrast, adjustment for television watching increased the gender gap by about 8%. Results indicated perceived confidence in overcoming barriers to physical activity and participation in community physical activity programs are factors related to the gender difference in physical activity.

Determinants of physical activity in active and low-active, sixth grade African-American youth

This study compared the determinants of physical activity in active and low-active African-American sixth grade students (N=108, 57 F, 51 M). Objective assessments of physical activity over a seven-day period were obtained using the CSA 7164 accelerometer. Students were classified as active if they exhibited three pr more 20-minute bouts of moderate to vigorous physical activity over the seven-day period. Relative to low-actives, active boys reported significantly higher levels of self-efficacy, greater involvement in community physical activity organizations, and were significantly more likely to perceive their mother us active. Relative to low-actives, active girls reported significantly higher levels of physical activity self-efficacy, greater positive beliefs regarding physical activity outcomes, and were significantly less likely to watch television or play video games for greater than or equal to 3 hrs/day. These observations provide preliminary guidance as to the design of physical activity interventions targeted at African-American youth.

The effect of the histological properties of tumors on transfection efficiency of electrically assisted gene delivery to solid tumors in mice

Uniform DNA distribution in tumors is a prerequisite step for high transfection efficiency in solid tumors. To improve the transfection efficiency of electrically assisted gene delivery to solid tumors in vivo, we explored how tumor histological properties affected transfection efficiency. In four different tumor types (B16F1, EAT, SA-1 and LPB), proteoglycan and collagen content was morphometrically analyzed, and cell size and cell density were determined in paraffin-embedded tumor sections under a transmission microscope. To demonstrate the influence of the histological properties of solid tumors on electrically assisted gene delivery, the correlation between histological properties and transfection efficiency with regard to the time interval between DNA injection and electroporation was determined. Our data demonstrate that soft tumors with larger spherical cells, low proteoglycan and collagen content, and low cell density are more effectively transfected (B16F1 and EAT) than rigid tumors with high proteoglycan and collagen content, small spindle-shaped cells and high cell density (LPB and SA-1). Furthermore, an optimal time interval for increased transfection exists only in soft tumors, this being in the range of 5-15 min. Therefore, knowledge about the histology of tumors is important in planning electrogene therapy with respect to the time interval between DNA injection and electroporation.

Management of a high grade pan stage schedule to reduce the steam consumption

MOST PAN stages in Australian factories use only five or six batch pans for the high grade massecuite production and operate these in a fairly rigid repeating production schedule. It is common that some of the pans are of large dropping capacity e.g. 150 to 240 t. Because of the relatively small number and large sizes of the pans, steam consumption varies widely through the schedule, often by ±30% about the mean value. Large fluctuations in steam consumption have implications for the steam generation/condensate management of the factory and the evaporators when bleed vapour is used. One of the objectives of a project to develop a supervisory control system for a pan stage is to (a) reduce the average steam consumption and (b) reduce the variation in the steam consumption. The operation of each of the high grade pans within the schedule at Macknade Mill was analysed to determine the idle (or buffer) time, time allocations for essential but unproductive operations (e.g. pan turn round, charging, slow ramping up of steam rates on pan start etc.), and productive time i.e. the time during boil-on of liquor and molasses feed. Empirical models were developed for each high grade pan on the stage to define the interdependence of the production rate and the evaporation rate for the different phases of each pan’s cycle. The data were analysed in a spreadsheet model to try to reduce and smooth the total steam consumption. This paper reports on the methodology developed in the model and the results of the investigations for the pan stage at Macknade Mill. It was found that the operation of the schedule severely restricted the ability to reduce the average steam consumption and smooth the steam flows. While longer cycle times provide increased flexibility the steam consumption profile was changed only slightly. The ability to cut massecuite on the run among pans, or the use of a high grade seed vessel, would assist in reducing the average steam consumption and the magnitude of the variations in steam flow.

Low-temperature PECVD of nanodevice-Grade nc-3C-SiC

In this work, we report a plasma-based synthesis of nanodevice-grade nc-3C-SiC films, with very high growth rates (7-9 nm min-1) at low and ULSI technology-compatible process temperatures (400-550 °C), featuring: (i) high nanocrystalline fraction (67% at 550 °C); (ii) good chemical purity; (iii) excellent stoichiometry throughout the entire film; (iv) wide optical band gap (3.22-3.71 eV); (v) refractive index close to that of single-crystalline 3C-SiC, and; (vi) clear, uniform, and defect-free Si-SiC interface. The counter-intuitive low SiC hydrogenation in a H2-rich plasma process is explained by hydrogen atom desorption-mediated crystallization.