Enhanced modeling features within TREETOPS

The original motivation for TREETOPS was to build a generic multi-body simulation and remove the burden of writing multi-body equations from the engineers. The motivation of the enhancement was twofold: (1) to extend the menu of built-in features (sensors, actuators, constraints, etc.) that did not require user code; and (2) to extend the control system design capabilities by linking with other government funded software (NASTRAN and MATLAB). These enhancements also serve to bridge the gap between structures and control groups. It is common on large space programs for the structures groups to build hi-fidelity models of the structure using NASTRAN and for the controls group to build lower order models because they lack the tools to incorporate the former into their analysis. Now the controls engineers can accept the hi-fidelity NASTRAN models into TREETOPS, add sensors and actuators, perform model reduction and couple the result directly into MATLAB to perform their design. The controller can then be imported directly into TREETOPS for non-linear, time-history simulation

Low-energy Antiproton Interaction with Helium

An ab initio potential for the interaction of the neutral helium atom with antiprotons and protons is calculated using the Born-Oppenheimer approximation. Using this potential, the annihilation cross section for antiprotons in the energy range 0.01 microvolt to 1 eV is calculated.Comment: 13 pages, 7 figures, LaTe

Tidal signals in ocean-bottom magnetic measurements of the Northwestern Pacific: observation versus prediction

Motional induction in the ocean by tides has long been observed by both land and satellite measurements of magnetic fields. While these signals are weak (∼10 nT) when compared to the main magnetic field, their persistent nature makes them important for consideration during geomagnetic field modelling. Previous studies have reported several discrepancies between observations and numerical predictions of the tidal magnetic signals and those studies were inconclusive of the source of the error. We address this issue by (1) analysing magnetometer data from ocean-bottom stations, where the low-noise and high-signal environment is most suitable for detecting the weak tidal magnetic signals, (2) by numerically predicting the magnetic field with a spatial resolution that is 16times higher than the previous studies and (3) by using four different models of upper-mantle conductivity. We use vector magnetic data from six ocean-bottom electromagnetic (OBEM) stations located in the Northwestern Pacific Ocean. The OBEM tidal amplitudes were derived using an iteratively re-weighted least-squares (IRLS) method and by limiting the analysis of lunar semidiurnal (M2), lunar elliptic semidinurnal (N2) and diurnal (O1) tidal modes to the night-time. Using a 3-D electromagnetic induction solver and the TPX07.2 tidal model, we predict the tidal magnetic signal. We use earth models with non-uniform oceans and four 1-D mantle sections underneath taken from Kuvshinov and Olsen, Shimizu etal. and Baba etal. to compare the effect of upper-mantle conductivity. We find that in general, the predictions and observations match within 10-70 per cent across all the stations for each of the tidal modes. The median normalized percent difference (NPD) between observed and predicted amplitudes for the tidal modes M2, N2 and O1 were 15 per cent, 47 per cent and 98 per cent, respectively, for all the stations and models. At the majority of stations, and for each of the tidal modes, the higher resolution (0.25°×0.25°) modelling gave amplitudes consistently closer to the observations than the lower resolution (1°×1°) modelling. The difference in lithospheric resistance east and west of the Izu-Bonin trench system seems to be affecting the model response and observations in the O1 tidal mode. This response is not seen in the M2 and N2 modes, thereby indicating that the O1 mode is more sensitive to lithospheric resistanc

Variations in Blood Pressures Amongst Day School Children and Boarding School Children in Western Maharashtra

Introduction: School children majorly face stress due to the pressure and expectations from their parents besides academics, athletics, etc. It is known that depression, stress increases blood pressure. Such wide variations in blood pressure at such a young age can increase the incidence of cerebrovascular accidents, ischemic heart diseases, renal failure and preterm death in the adulthood of such children. This survey will guide the parents and teachers to the various problems student face and how can they help the student cope with it. Method: The blood pressure of each student was taken three times to reduce them to minimise the possibility of errors and the blood pressures of all the students were compared according to their age (13-16 years) and the schooling type (boarders and day scholars). Results:  On comparing the prehypertensive stage, the numbers of pre-hypertensives are found to be greater in the age group of 15 years in both day scholars and boarders i.e. 14% and 8% respectively. The on comparing the schooling type the day scholars have a greater number of prehypertensive i.e. 25% than boarders which is 17%. Though pre-hypertensives are higher in the age group of 15 years, but the numbers of hypertensives are more in 14 years of age which is 7% (6% in hypertension stage I and 1% in hypertension stage II) in day scholars and 4% (3% in hypertension stage I and 1% in hypertension stage II) in boarders. In schooling type, a similar trend as that of prehypertension is seen i.e. in day scholars 14% students are in hypertension stage I and 3% students are in hypertension stage II making a total of 17% of hypertensive in day scholars. Similarly, in boarders there are 6% in hypertension stage I and 1% in hypertension stage II making 7% hypertensive in boarders, thereby showing a higher percentage of hypertensive in day scholars. Conclusion: The study revealed Percentage of students in hypertension stage I and hypertension stage II were found more in day scholars (14% HT STAGE I and 3% HT STAGE II) than boarders (6%HT STAGE I and 1% HT STAGE II) respectively. Thus, it can be very well concluded that 17% of day school children and 7% boarders were found to be in hypertensive. Keywords: Variations in blood pressures, Day school; Boarding school Children; Western Maharashtra. &nbsp

Variations in Blood Pressures Amongst Day School Children and Boarding School Children in Western Maharashtra

Introduction: School children majorly face stress due to the pressure and expectations from their parents besides academics, athletics, etc. It is known that depression, stress increases blood pressure. Such wide variations in blood pressure at such a young age can increase the incidence of cerebrovascular accidents, ischemic heart diseases, renal failure and preterm death in the adulthood of such children. This survey will guide the parents and teachers to the various problems student face and how can they help the student cope with it. Method: The blood pressure of each student was taken three times to reduce them to minimise the possibility of errors and the blood pressures of all the students were compared according to their age (13-16 years) and the schooling type (boarders and day scholars). Results:  On comparing the prehypertensive stage, the numbers of pre-hypertensives are found to be greater in the age group of 15 years in both day scholars and boarders i.e. 14% and 8% respectively. The on comparing the schooling type the day scholars have a greater number of prehypertensive i.e. 25% than boarders which is 17%. Though pre-hypertensives are higher in the age group of 15 years, but the numbers of hypertensives are more in 14 years of age which is 7% (6% in hypertension stage I and 1% in hypertension stage II) in day scholars and 4% (3% in hypertension stage I and 1% in hypertension stage II) in boarders. In schooling type, a similar trend as that of prehypertension is seen i.e. in day scholars 14% students are in hypertension stage I and 3% students are in hypertension stage II making a total of 17% of hypertensive in day scholars. Similarly, in boarders there are 6% in hypertension stage I and 1% in hypertension stage II making 7% hypertensive in boarders, thereby showing a higher percentage of hypertensive in day scholars. Conclusion: The study revealed Percentage of students in hypertension stage I and hypertension stage II were found more in day scholars (14% HT STAGE I and 3% HT STAGE II) than boarders (6%HT STAGE I and 1% HT STAGE II) respectively. Thus, it can be very well concluded that 17% of day school children and 7% boarders were found to be in hypertensive. Keywords: Variations in blood pressures, Day school; Boarding school Children; Western Maharashtra. &nbsp

Carbohydrate specificity and salt-bridge mediated conformational change in acidic winged bean agglutinin

Structures of two crystal forms of the dimeric acidic winged bean agglutinin (WBAII) complexed with methyl-α-D-galactose have been determined at 3.0 Å and 3.3 Å resolution. The subunit structure and dimerisation of the lectin are similar to those of the basic lectin from winged bean (WBAI) and the lectin from Erythrina corallodendron (EcorL). The conformation of a loop and its orientation with respect to the rest of the molecule in WBAII are, however, different from those in all the other legume lectins of known structure. This difference appears to have been caused by the formation of two strategically placed salt bridges in the former. Modelling based on the crystal structures provides a rationale for the specificity of the lectin, which is very different from that of WBAI, for the H-antigenic determinant responsible for O blood group reactivity. It also leads to a qualitative explanation for the thermodynamic data on sugar-binding to the lectin, with special emphasis on the role of a tyrosyl residue in the variable loop in the sugar-binding region in generating the carbohydrate specificity of WBAII