No evidence that polymorphisms of brain regulator genes Microcephalin and ASPM are associated with general mental ability, head circumference or altruism

We test the hypothesis that polymorphisms of the brain regulator genes MCPH1 and ASPM contribute to variations in human brain size and its correlates. We measured general mental ability, head circumference and social intelligence in 644 Canadian adults (496 Caucasians, 36 Orientals, 84 Mixed Race/Other and 28 Blacks; 257 men and 387 women). The gene polymorphisms were assessed from buccal DNA; mental ability by Wonderlic Personnel Test and Multidimensional Aptitude Battery; head circumference by stretchless tape; and social intelligence by prosocial attitude questionnaires. Although all measures were construct valid and the allele frequencies showed expected population differences, no relationship was found between the genes and any of the criteria. Among Caucasian 18–25 year olds, for example, the two mental ability tests correlated with each other (r=0.78, N=476, p<0.001), with head circumference (r=0.17, N=182, p<0.05) and with prosocial attitudes (r=0.23, N=182, p<0.001)

Long Hole Film Cooling Dataset for CFD Development - Flow and Film Effectiveness

An experiment investigating flow and heat transfer of long (length to diameter ratio of 18) cylindrical film cooling holes has been completed. In this paper, the thermal field in the flow and on the surface of the film cooled flat plate is presented for nominal freestream turbulence intensities of 1.5 and 8 percent. The holes are inclined at 30 deg above the downstream direction, injecting chilled air of density ratio 1.0 onto the surface of a flat plate. The diameter of the hole is 0.75 in. (approx. 0.02 m) with center to center spacing (pitch) of 3 hole diameters. Coolant was injected into the mainstream flow at nominal blowing ratios of 0.5, 1.0, 1.5, and 2.0. The Reynolds number of the freestream was approximately 11,000 based on hole diameter. Thermocouple surveys were used to characterize the thermal field. Infrared thermography was used to determine the adiabatic film effectiveness on the plate. Hotwire anemometry was used to provide flowfield physics and turbulence measurements. The results are compared to existing data in the literature. The aim of this work is to produce a benchmark dataset for Computational Fluid Dynamics (CFD) development to eliminate the effects of hole length to diameter ratio and to improve resolution in the near-hole region. In this report, a Time Filtered Navier Stokes (TFNS), also known as Partially Resolved Navier Stokes (PRNS), method that was implemented in the Glenn-HT code is used to model coolant-mainstream interaction. This method is a high fidelity unsteady method that aims to represent large scale flow features and mixing more accurately

On amplitude scaling of active separation control

Various scaling options for the effects of excitation magnitude on the lift alternation due to zero-mass-flux periodic excitation for boundary layer separation control are examined. Physical scaling analysis leads to five amplitude parameters. The different scaling laws are examined using experimental data acquired at low Reynolds numbers and various angles of attack. The results indicate that both the velocity ratio and the momentum coefficient, commonly used for amplitude scaling of separation control applications, do not scale the current data-set. For 2D excitation with a Strouhal number of order unity, a Reynolds weighted momentum coefficient provides reasonable scaling. For 3D excitation with a Strouhal number greater than 10, the Reynolds scaled momentum coefficient, the Strouhal scaled velocity ratio and the newly defined vorticity-flux coefficient, all provide good scaling. The airfoil incidence variations are accounted for by using the velocity at the boundary layer edge at the actuation location, rather than the fixed free-stream velocity as a velocity scale. The main finding of this study is that the Reynolds number scaled momentum coefficient provides good amplitude scaling for the entire current data set

The Effect of Bolus Vitamin D-3 Supplementation on Distal Radius Fracture Healing: A Randomized Controlled Trial Using HR-pQCT

Vitamin D is an important factor in bone metabolism. Animal studies have shown a positive effect of vitamin D3 supplementation on fracture healing, but evidence from clinical trials is inconclusive. A randomized controlled trial was performed to assess the effect of vitamin D3 supplementation on fracture healing using high-resolution peripheral quantitative computed tomography (HR-pQCT) based outcome parameters. Thirty-two postmenopausal women with a conservatively treated distal radius fracture were included within two weeks post-fracture and randomized to a low-dose (N = 10) and a high-dose (N = 11) vitamin D intervention group receiving a 6-week bolus dose, equivalent to 700 and 1,800 IU vitamin D3 supplementation per day respectively, in addition to a control group (N = 11) receiving no supplementation. After the baseline visit 1-2 weeks post-fracture, follow-up visits were scheduled at 3-4, 6-8 and 12 weeks post-fracture. At each visit, HR-pQCT scans of the fractured radius were performed. Cortical and trabecular bone density and microarchitectural parameters and μFEA derived torsion, compression and bending stiffness were assessed. Additionally, serum markers of bone resorption (C-terminal telopeptide of type I collagen; CTX) and bone formation (N-terminal propeptide of type I procollagen; PINP) were measured. Baseline serum levels of 25(OH)D3 were < 50 nmol/L in 33% of all participants and < 75 nmol/L in 70%. Compared to the control group, high-dose vitamin D3 supplementation resulted in a decreased trabecular number (regression coefficient B: -0.22; p < 0.01) and lower compression stiffness (B: -3.63; p < 0.05, together with an increase in the bone resorption marker CTX (B: 0.062; p < 0.05). No statistically significant differences were observed between the control and low-dose intervention group. In conclusion, the bolus equivalent of 700 U/day vitamin D3 supplementation in a Western postmenopausal population does not improve distal radius fracture healing and an equivalent dose of 1,800 IU/day may be detrimental in restoring bone stiffness during the first 12 weeks of fracture healing