Non-Newtonian gravity or gravity anomalies?

Geophysical measurements of G differ from laboratory values, indicating that gravity may be non-Newtonian. A spherical harmonic formulation is presented for the variation of (Newtonian) gravity inside the Earth. Using the GEM-10B Earth Gravitational Field Model, it is shown that long-wavelength gravity anomalies, if not corrected, may masquerade as non-Newtonian gravity by providing significant influences on experimental observation of delta g/delta r and G. An apparent contradiction in other studies is also resolved: i.e., local densities appear in equations when average densities of layers seem to be called for

Secondary Flow and Upstream Dynamics in Double Bifurcation Model

Flow behavior in bifurcation models is of great importance to health risk assessments and pulmonary drug delivery. This is particularly true of secondary flow behavior in multi-bifurcation models. Previously, both numerical and experimental methods have shown that four-vortex secondary flow structures can develop in the cross-sections of grand-daughter branches. This work shows that the development of secondary flow in the grand-daughter tubes is due to local stretching of vortex lines in the upstream DT. Scaling arguments have been used to derive two critical parameters governing this particular vorticity transport problem. A simple model for vorticity generation and transport is proposed, taking into account the geometric limitations imposed by the rigid walls of the tubes.Singapore-MIT Alliance (SMA

Transport of Sub-micron Aerosols in Bifurcations

The convective-diffusive transport of sub-micron aerosols in an oscillatory laminar flow within a 2-D single bifurcation is studied, using order-of-magnitude analysis and numerical simulation using a commercial software (FEMLAB®). Based on the similarity between momentum and mass transfer equations, various transient mass transport regimes are classified and scaled according to Strouhal and beta numbers. Results show that the mass transfer rate is highest at the carinal ridge and there is a phase-shift in diffusive transport time if the beta number is greater than one. It is also shown that diffusive mass transfer becomes independent of the oscillating outer flow if the Strouhal number is greater than one.Singapore-MIT Alliance (SMA

Algebras of integrals

A classical theorem in mechanics states that a Hamiltonian which is invariant under a symmetry group admits additional integral s of motion. Thi s paper investigates the converse of the above theorem. If a Hamiltonian admits integrals then a symmetry can be constructed and the flaw studied on a quotient space. The quotient space is shown to be symplectic  and the resulting flow Hamiltonian. The constructions used are similar to the recent constructions of Nehoroshev, Marsden and Weinstein and Meyer. The general theory presented is used to give an intrinsic derivation of Hamilton's equations of motion. Al so special local coordinates are given which display the integrals in a simple form

KINEMATICS AND PHYSIOLOGICAL EFFECT OF A SYNCHRONIZED BIPEDAL “RISE-SIT-GO” CYCLING EXERCISE

This study demonstrated the kinematics and physiological effect of a synchronized bipedal cycling exercise. Fifteen male subjects performed a 30-minutes exercise on a synchronized bipedal stationary bike and a conventional stationary bike at same cycling speed. The performance was evaluated by a metabolic testing system, a subjective rating of perceived exertion, an electromyography system and a motion analysis system, and was compared by paired t-tests. Results showed significant increases in oxygen uptake, energy expenditure, rating of perceived exertion, muscle activity in triceps, biceps, rectus abdominis, left gluteus maximus, left medial gastrocnemius, right tibialis anterior and left tibialis anterior, and range of motion of left hip, left and right knees, shoulders, elbows and wrists. The synchronized bipedal cycling exercise was more physically demanding

Associations Between Occupational Therapy Students’ Approaches to Studying and Their Academic Grade Results: A Cross-Sectional and Cross-Cultural Study

Students’ approaches to studying are generally viewed as essential for their learning outcomes and are often described as being either deep, strategic or surface. However, research on associations between study approaches and academic outcomes among occupational therapy students are rare, as are studies that include cross-cultural comparisons. The objective of this study was to assess the degree to which the deep, strategic, and surface approaches to studying were associated with occupational therapy students’ grade point average, in the total sample and when stratified by country, while controlling for age, gender and time spent on independent study. Seven hundred and twelve students from four countries (Australia, Norway, Hong Kong, and Singapore) completed the Approaches and Study Skills Inventory for Students, and sum scores were calculated for the deep, strategic, and surface scales. Linear regression analyses were used to investigate associations between scale scores and grade point average, in the total sample and within each of the four sub-samples. The results showed that in the total sample, and in the Australia and Singapore sub-samples, none of the scales was associated with grade point average. In Hong Kong, lower deep approach scores and higher strategic approach scores were associated with higher grade point average. In Norway, higher strategic approach scores and lower surface approach scores were associated with higher grade point average. The study found that the approaches to studying scales were relevant for understanding academic performance among occupational therapy students in Norway and Hong Kong, but appeared less useful in the Australian and Singapore contexts

Innovative Virtual Reality (VR) Application for Preventing of Falls among Chinese Older Adults : A Usability and Acceptance Exploratory Study

Objective: Full immersive virtual reality (VR) technology shows potential for reducing the risks of falls in older adults. There is yet little evidence to support the usability and acceptance on using VR technology application in community aged care service. The study reports on research that aims to address that gap by evaluating the usefulness and acceptance of using an innovative VR application among Chinese older adults from Hong Kong. Methods: A single-arm exploratory study was conducted to evaluate how the participants experienced the use of a fully immersive cave automatic virtual environment (CAVE) VR program on fall prevention. Thirty-one participants were recruited by convenience sampling based on their fall concerns and potential risk of falls. The participants completed 16 training sessions over eight weeks using the VR CAVE application. They were asked to complete a VR usability questionnaire (HK-version) based on the Technology Acceptance Model and previous research, and they took fall risk assessments at the pretest, posttest, and follow-up. Results: The participants’ group significantly showed improvements in reducing the risk factors of falls including balance, functional mobility, walking speed, and fear of falling after VR intervention. Perceived usefulness (PU), perceived enjoyment (PE), user experience (UE), and intention to use (IU) had an overall significant change at different time points. These are important factors to influence the participants’ acceptance of the use of VR technology applications. Perceived ease of use (PEOU) and social norms (SNs) had an inconsistent result, and some items had low validity. The findings indicated a positive training effect on fall prevention and high acceptance of the adoption of the VR technology application. Conclusion: This study supports the growing evidence on the usefulness and acceptance of using full immersive VR training on fall prevention among Chinese older adults. They perceived that the VR CAVE application was useful and innovative as an effective fall prevention training. Technically, the application of VR CAVE technology faces many challenges and is not easily manageable under COVID-19 restrictions and the limitation on technological adaptation for older adults. However, investment in full immersive VR technology application is supported for future adoption in aged care and rehabilitation services