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Multi-Photon Polymerization (MPP) is a technique used to fabricate complex micro-scale 3D structures using ultra-short laser pulses. Typically, MPP is used to manufacture micron-scale components in photopolymer materials. However, the development of micron scale processes that can produce components from multiple materials within a single manufacturing step would be advantageous. This would allow the inclusion of particles that are manipulated and embedded within structures with sub-micron feature sizes. To achieve this, an MPP system was combined with an optical trapping (OT) setup in order to independently manipulate microparticles in the x, y and z planes. Particles were transported into the fabrication site using the OT and encapsulated using the MPP laser. Here it is shown that combining the OT capabilities with an additive manufacturing technique enables the production of complex multi-material artifacts. [ABSTRACT FROM AUTHOR]

Within the framework of a Boltzmann-Lorentz equation, we analyze the dynamics of a granular rotor immersed in a bath of thermalized particles in the presence of a frictional torque on the axis. In numerical simulations of the equation, we observe two scaling regimes at low and high bath temperatures. In the large friction limit, we obtain the exact solution of a model corresponding to asymptotic behavior of the Boltzmann-Lorentz equation. In the limit of large rotor mass and small friction, we derive a Fokker- Planck equation for which the exact solution is also obtained. [ABSTRACT FROM AUTHOR]

We study convective motion in vertically vibrated three-dimensional granular beds by comparing the predictions of a model based on a hydrodynamic description to Navier–Stokes order with experimental results obtained using positron emission particle tracking (PEPT). The three-dimensional conservation equations relating mass, momentum and energy are solved using the finite element (FE) method for a viscous vibrofluidized bed by using only observable system parameters such as particle number, size, mass and coefficients of restitution. The mean velocity profiles from the viscous model show reasonable agreement with the experimental results at relatively low altitudes for the range of experimental values studied, though the velocity fields at higher altitudes were systematically underestimated by the model. We confirm that the convection rolls are influenced by the sidewall coefficient of restitution and demonstrate the scaling relationships that operate, where increasing amplitude of vibration leads to a reduction in the angular velocity of the rolls. [ABSTRACT FROM PUBLISHER]

Method To test the hypothesis that psychosocial symptomatology differs by country of origin and acculturation among Hispanic women, we examined 419 women, aged 42-52 years at baseline, enrolled in the New Jersey site of the Study of Women's Health Across the Nation (SWAN). Women were categorized into six groups: Central (CA, n = 29) or South American (SA, n = 106), Puerto Rican (PR, n = 56), Dominican (D, n = 42), Cuban (Cu, n = 44) and non-Hispanic Caucasian (NHC, n = 142). Acculturation, depressive symptoms, hostility/cynicism, mistreatment/discrimination, sleep quality, social support, and perceived stress were assessed at baseline. Physical functioning, trait anxiety and anger were assessed at the fourth annual follow-up. Comparisons between Hispanic and non-Hispanic Caucasians used χ2, t test or non-parametric alternatives; ANOVA or Kruskal-Wallis testing examined differences among the five Hispanic sub-groups. Multivariable regression models used PR women as the reference group. Results Hispanic women were overall less educated, less acculturated ( p < 0.001 for both) and reported more depressive symptoms, cynicism, perceived stress, and less mistreatment/discrimination than NHCs. Along with D women, PR women reported worse sleep than Cu women ( p < 0.01) and more trait anxiety than SA and Cu women ( p < 0.01). Yet, PR women were most acculturated (21.4% highly acculturated vs. CA (0.0%), D (4.8%), SA (4.8%) and Cu (2.3%) women; p < 0.001). In regression models, PR women reported depressive symptoms more frequently than D, Cu, or SA women, and reported trait anxiety more frequently than Cu or SA women. Greater acculturation was associated with more favorable psychosocial status, but PR ethnicity was negatively related to psychosocial status. Conclusion Psychosocial symptomatology among Hispanic women differs by country of origin and the relatively adverse profile of Puerto Rican women is not explained by acculturation. [ABSTRACT FROM AUTHOR]

Introduction Since the designation of people as Hispanic involves the amalgamation of a number of different cultures and languages, we sought to test the hypothesis that menopausal symptoms would differ among Hispanic women, based upon country of origin and degree of acculturation. Methods A total of 419 women, aged 42–52 years at baseline, were categorized as: Central American (CA, n = 29) or South American (SA, n = 106), Puerto Rican (PR, n = 56), Dominican (D, n = 42), Cuban (Cu, n = 44) and non-Hispanic Caucasian ( n = 142). We assessed vasomotor symptoms, vaginal dryness and trouble in sleeping. Hispanics and non-Hispanic Caucasians were compared using the χ2 test, t test or non-parametric alternatives; ANOVA or Kruskal–Wallis testing examined differences among the five Hispanic sub-groups. Multivariable regression models used PR women as the reference group. Results Hispanic women were overall less educated, less acculturated ( p < 0.001 for both) than non-Hispanic Caucasians and more of them reported vasomotor symptoms (34.1–72.4% vs. 38.3% among non-Hispanic Caucasians; p = 0.0293) and vaginal dryness (17.9–58.6% vs. 21.1% among non-Hispanic Caucasians, p = 0.0287). Among Hispanics, more CA women reported vasomotor symptoms than D, Cu, SA, or PR women (72.4% vs. 45.2%, 34.1%, 50.9%, and 51.8%, respectively). More CA (58.6%) and D women (38.1%) reported vaginal dryness than PR (17.9%), Cu (25.0%) and SA (31.4%) women. More PR and D women reported trouble in sleeping (66.1 and 64.3%, respectively) compared to CA (51.7%), Cu (36.4%), and SA (45.3%) women. Conclusion Symptoms associated with menopause among Hispanic women differed by country of origin but not acculturation. Central American women appear to be at greatest risk for both vasomotor symptoms and vaginal dryness. [ABSTRACT FROM AUTHOR]

Carbohydrate is a key energy source during exercise. Factors such as fed/metabolic state, diet, type, intensity/duration of exercise, and training status influence its use during exercise and whether external (e.g., diet), internal (e.g., muscle or liver glycogen), or blood sources are used. Along with hydration, carbohydrate availability is a primary factor leading to muscular or central fatigue. Proper timing of carbohydrate intake before, during, and after exercise can sustain performance and optimize recovery. Carbohydrate type can influence osmotic, digestibility, glycemic, and insulinemic effects. This article briefly reviews these key concepts and provides practical guidance for application to athletes. [ABSTRACT FROM AUTHOR]

The three-dimensional conservation equations relating energy and momentum transfer in a vibrated three-dimensional granular bed have been solved numerically by the finite element method. Two closures based on granular kinetic theory were used: one, the standard Fourier law relating heat flux to temperature gradient and the other, including an additional concentration gradient term. Each prediction of the two-dimensional axisymmetric granular temperature and packing fraction fields was compared against a one-dimensional model and three-dimensional experimental results, acquired using the technique of positron emission particle tracking. Both closures resulted in solutions that were in reasonable agreement with the experimental results, but it was found that differences between the predictions of each of the closures were relatively small in comparison to the anisotropy of the experimentally determined temperature distribution. [ABSTRACT FROM AUTHOR]

A comparison of the predictions of a simple kinetic theory with experimental and numerical results for a vibrated granular bed consisting of nearly elastic particles of two sizes has been performed. The results show good agreement between the data sets for a range of numbers of each size of particle, and are particularly good for particle beds containing similar proportions of each species. The agreement suggests that such a model may be a good starting point for describing polydisperse systems of granular flows. [ABSTRACT FROM AUTHOR]

The spontaneous formation of cracks in biscuits following baking, also known as checking, is an issue that manufacturers would like to be able to predict and avoid. Unfortunately the mechanisms driving this phenomenon are not well understood. Speckle interferometry was used to study moisture-induced in-plane strain development in biscuits. This sensitive and non-contacting technique for measuring surface displacements has two major advantages over more commonly used methods; firstly, strains can be detected at a far higher sensitivity (down to 2 × 10-6) than previously accessible and secondly the method is a whole-field technique, enabling observation of the development of strain distributions during moisture migration. For biscuits exposed to step changes in humidity, initial strain rates of up to 10-5min-1 were measured, which decreased as the moisture content approached equilibrium, leading to an accumulated strain of ~10-2 after 48 h. Under these conditions, a homogeneous, uniform strain distribution was observed. The data were used to calculate the hygroscopic expansion coefficient, which was linearly related to moisture content and provides the necessary constitutive link between strain and biscuit moisture content needed to model biscuit checking. [ABSTRACT FROM AUTHOR]

Creatine supplementation may enhance creatine and creatine phosphate levels in skeletal muscle and may be associated with an augmentation of lean body mass and increased performance during quickburst, high-intensity activities. While numerous investigations have been performed focusing on skeletal muscle, relatively less is known as to the potential impact of supplementation on other tissue that contains creatine, such as the heart. To provide some insight in this matter, young men (ages 20-35) were provided with 25 grams of creatine monohydrate daily for seven days and were assessed by echocardiography before and after supplementation and compared to controls. Measurements of left ventricular mass, cardiac output, stroke volume, ejection fraction, fractional shortening and E/A ratio were not significantly influenced by creatine supplementation. The results of this preliminary investigation suggest that creatine supplementation does not significantly influence cardiac mass and resting performance in healthy young men. [ABSTRACT FROM PUBLISHER]

The velocity autocorrelation functions of grains moving in highly fluidized three-dimensional granular beds have been determined for the first time. Positron emission particle tracking was used to determine the location of a tracer particle. The velocity auto- and cross-correlation functions were then calculated following estimation of the velocities of the grains. The cross-correlations were found to be about zero for all times and the velocity autocorrelation functions differed in the x and y directions. A numerical study was performed to model the velocity auto-correlation function in the y-direction and this analysis was found to capture many of the observed experimental features. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine if a high fat diet having a 2:1 saturated-polyunsaturated fatty acid ratio exacerbates signs of copper deficiency. Male weanling Long-Evans rats were randomly placed into one of the following treatment groups: adequate copper low fat or deficient copper high fat. The levels of fat used were 31 or 12% of daily energy, and copper concentrations were 94.5 micromol/kg and <15.8 micromol/kg in the copper-adequate and copper-deficient diets, respectively. Cardiac hypertrophy as well as lower liver copper levels and superoxide dismutase activity were observed in both groups of copper-deficient rats. Irrespective of copper level, consumption of the high fat diet resulted in the thickening of the interventricular septum and left ventricular free wall. Electrocardiograms revealed that the copper-deficient high fat diet led to a significantly smaller QT interval compared with all other groups. Significantly greater S-wave voltage due to copper deficiency was observed. Significantly lower heart cytochrome c oxidase (CCO) activity was found in the copper-deficient groups with the copper deficient high fat group showing the lowest activity. Western blots of the cardiac non-myofibrillar fraction demonstrated lower amounts of CCO nuclear encoded peptides in the copper-deficient groups, with the least amount seen in the copper-deficient high fat treatment. These data suggest that a high level of dietary fat exacerbates some of the signs of copper deficiency. [ABSTRACT FROM AUTHOR]

The article reports that there is a conspicuous phenomenon in state mental hospitals relating to fluctuations of admission rates. These seem to occur with almost predictable regularity and have been attributed to changing economic, social, and climatic conditions. William N. Chambers' study dealt exclusively with seasonal variations in neuro-psychiatric admissions to a military hospital, which were highest in March. P.A. Hauck compared monthly admission rates in four state hospitals for three years, with highest admission rate in January. P.A. Hauck and R.G. Armstrong examined admission rates to a state hospital over a 37 year period, the data categorized by sexes. The month of highest admissions was June.