Sustained load crack growth design data for Ti-6Al-4V titanium alloy tanks containing hydrazine

Sustained load crack growth data for Ti-6Al-4V titanium alloy in hydrazine per MIL-P-26536 and refined hydrazine are presented. Fracture mechanics data on crack growth thresholds for heat-treated forgings, aged and unaged welds, and aged and unaged heat-affected zones are reported. Fracture mechanics design curves of crack growth threshold stress intensity versus temperature are generated from 40 to 71 C

Towards mechanomagnetics in elastic crystals: insights from [Cu(acac)2_2]

We predict that the magnetic properties of \cuacac, an elastically flexible crystal, change dramatically when the crystal is bent. We find that unbent \cuacac\ is an almost perfect Tomonaga-Luttinger liquid. Broken-symmetry density functional calculations reveal that the magnetic exchange interactions along the chains is an order of magnitude larger than the interchain exchange. The geometrically frustrated interchain interactions cannot magnetically order the material at any experimentally accessible temperature. The ordering temperature ($T_N$), calculated from the chain random phase approximation, increases by approximately 24 orders of magnitude when the material is bent. We demonstrate that geometric frustration both suppresses $T_N$ and enhances the sensitivity of $T_N$ to bending. In \cuacac, $T_N$ is extremely sensitive to bending, but remains too low for practical applications, even when bent. Partially frustrated materials could achieve the balance of high $T_N$ and good sensitivity to bending required for practical applications of mechanomagnetic elastic crystals

Vitamin D Status and Bone Mineral Density in Female Collegiate Dancers and Cheerleaders

Bone mineral density reflects an athlete’s cumulative history of energy availability, physical activity, and menstrual status, as well as nutritional and environmental factors. Although sports with high-impact loading are associated with higher bone mineral density than low-impact or non-impact sports, confounding variables are differences in the athletes’ body size and sport-specific training. The purpose of this study was to determine if bone mineral density (BMD) and vitamin D status are different between two groups of female collegiate athletes who have comparable body size/weight requirements, but who engage in qualitatively different training regimens. Full body, spine and dual femur BMD was assessed by dual energy X-ray absorptiometry (DXA) in members of a university pep-dance team (n = 10) or cheer team (n = 9), ages 18-22. Plasma vitamin D status was assessed by ELIZA. There was no significant difference between the groups for total body BMD (1.23 g/cm2 dance vs 1.22 g/cm2 cheer, P = 0.70), spine BMD (1.39 g/cm2 dance vs 1.36 g/cm2 cheer, P = 0.72) or dual femur BMD (1.20 g/cm2 dance vs 1.11 g/cm2, P = 0.23). Insufficient serum vitamin D status (20-32 ng/mL) was found in 74% of the athletes (27 ± 4 ng/mL, dance and 25 ± 8 ng/mL, cheer). In addition, estimated daily vitamin D and calcium intakes were less than the RDA for both dancers and cheerleaders. Despite nutritional insufficiencies, BMD was not significantly different between the low-impact activity pep dance team and high-impact activity cheer team, suggesting that the type of physical activity was not as important for BMD in these athletes as participating in 20+ hours a week of physical activity, which could have counteracted the negative effects of the nutrient insufficiencies on their bone health

An investigation of children's peer trust across culture: is the composition of peer trust universal?

The components of children's trust in same-gender peers (trust beliefs, ascribed trustworthiness, and dyadic reciprocal trust) were examined in samples of 8- to 11-year-olds from the UK, Italy, and Japan. Trust was assessed by children's ratings of the extent to which same-gender classmates kept promises and kept secrets. Social relations analyses confirmed that children from each country showed significant: (a) actor variance demonstrating reliable individual differences in trust beliefs, (b) partner variance demonstrating reliable individual differences in ascribed trustworthiness, and (c ) relationship variance demonstrating unique relationships between interaction partners. Cultural differences in trust beliefs and ascribed trustworthiness also emerged and these differences were attributed to the tendency for children from cultures that value societal goals to share personal information with the peer group

Food addiction: a valid concept?

Can food be addictive? What does it mean to be a food addict? Do common underlying neurobiological mechanisms contribute to drug and food addiction? These vexing questions have been the subject of considerable interest and debate in recent years, driven in large part by the major health concerns associated with dramatically increasing body weights and rates of obesity in the United States, Europe, and other regions with developed economies. No clear consensus has yet emerged on the validity of the concept of food addiction and whether some individuals who struggle to control their food intake can be considered food addicts. Some, including Fletcher, have argued that the concept of food addiction is unsupported, as many of the defining features of drug addiction are not seen in the context of feeding behaviors. Others, Kenny included, have argued that food and drug addiction share similar features that may reflect common underlying neural mechanisms. Here, Fletcher and Kenny argue the merits of these opposing positions on the concept of food addiction.Wellcome Trust Bernard Wolfe Health Neurosciencce Fund National Institutes of Health, US

Difference score correlations in relationship research: A conceptual primer

The practice of computing correlations between “difference” or “discrepancy” scores and an outcome variable is common in many areas of social science. Relationship researchers most commonly use difference scores to index the (dis)similarity of members of two-person relationships. Using an intuitive, graphical approach—and avoiding formulas and pointing fingers—we illustrate problems with using difference score correlations in relationship research, suggest ways to ensure that difference score correlations are maximally informative, and briefly review alternatives to difference score correlations in studying similarity, accuracy, and related constructs.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73008/1/j.1475-6811.1999.tb00206.x.pd

Kebijakan Parkir Kota Batam Dalam Meningkatkan Pendapatan Asli Daerah

The growth rate of motor vehicles in Batam City in recent years runs very rapidly. This levy will increase the original revenue of Batam City, But the implementation of the policy of Bylaw No.1 / 2012 on parking that has been running for three years (2012-2015) does not generate significant revenue on parking charges. The Purpose of this research is how the implementationn of parking management system based on evaluation of the policy of Bylaw No.1 / 2012 on parking Btam City. Data retrieval method is done by observation and documentation. Informant selection technique is done by purposive sampling, technical data analysis is done by data reduction, data presentation and conclusion drawing. The result of the research is that the policy of Batam City Government in increasing its achievement PAD not yet optimal, due to some obstacles such as: parking management system is not feasible, there is no public satisfaction survey index to measure the extent to which the achievement of parking policy in Batam City, Human Power that needs coaching and training. Its solution of Batan City government re-filed Ranpeda about parking with the intention of changing parking rates, changing the system of parking management and service facility improvemen

ESTIMATING STEP PARAMETERS USING PHOTOELECTRIC CELLS

The purpose of this study was to assess the OptoJumpTM photocell system (Microgate, Bolzano, Italy) in measuring step length and ground contact time during running. In two separate investigations, eight individuals repeatedly ran through a three metre section of OptoJumpTM track. Ground contact times were compared to concurrent force platform measures whereas step lengths were compared to physically measured lengths from foot imprints left in powder. Estimates of step length showed excellent validity with only 0.4% difference between methods and an intraclass correlation coefficient of 0.999. The OptoJumpTM systematically overestimated contact time with a mean bias of 2.7% compared to force platform measures. These results suggest that the OptoJumpTM can be effectively used to estimate step characteristics in real time

Reconstructing 3D x-ray CT images of polymer gel dosimeters using the zero-scan method

In this study x-ray CT has been used to produce a 3D image of an irradiated PAGAT gel sample, with noise-reduction achieved using the ‘zero-scan’ method. The gel was repeatedly CT scanned and a linear fit to the varying Hounsfield unit of each pixel in the 3D volume was evaluated across the repeated scans, allowing a zero-scan extrapolation of the image to be obtained. To minimise heating of the CT scanner’s x-ray tube, this study used a large slice thickness (1 cm), to provide image slices across the irradiated region of the gel, and a relatively small number of CT scans (63), to extrapolate the zero-scan image. The resulting set of transverse images shows reduced noise compared to images from the initial CT scan of the gel, without being degraded by the additional radiation dose delivered to the gel during the repeated scanning. The full, 3D image of the gel has a low spatial resolution in the longitudinal direction, due to the selected scan parameters. Nonetheless, important features of the dose distribution are apparent in the 3D x-ray CT scan of the gel. The results of this study demonstrate that the zero-scan extrapolation method can be applied to the reconstruction of multiple x-ray CT slices, to provide useful 2D and 3D images of irradiated dosimetry gels