Design and testing of a high power spacecraft thermal management system

The design and test results are presented of an ammonia hybrid capillary pumped loop thermal control system which could be used for heat acquisition and transport on future large space platforms and attached payloads, such as those associated with the NASA Space Station. The High Power Spacecraft Thermal Management System (HPSTM) can operate as either a passive, capillary pumped two phase thermal control system, or, when additional pressure head is required, as a mechanically pumped loop. Testing has shown that in the capillary mode, the HPSTM evaporators can acquire a total heat load of between 600 W and 24 kW, transported over 10 meters, at a maximum heat flux density of 4.3 W/sq cm. With the mechanical pump circulating the ammonia, a heat acquisition potential of 52 kW was demonstrated for 15 minutes without an evaporator failure. These results represent a significant improvement over the maximum transport capability previously displayed in other capillary systems. The HPSTM system still retains the proven capillary capabilities of heat load sharing and flow control between evaporator plates, rapid power cycling, and nonuniform heating in both the capillary and hybrid operating modes

The client-binding domain of the cochaperone Sgt2 has a helical-hand structure that binds a short hydrophobic helix

The targeting and insertion of tail-anchored (TA) integral membrane proteins (IMP) into the correct membrane is critical for cellular homeostasis. The fungal protein Sgt2, and its human homolog SGTA, binds hydrophobic clients and is the entry point for targeting of ER-bound TA IMPs. Here we reveal molecular details that underlie the mechanism of Sgt2 binding to TA IMP clients. We establish that the Sgt2 C-terminal region is flexible but conserved and sufficient for client binding. A molecular model for this domain reveals a helical hand forming a hydrophobic groove, consistent with a higher affinity for TA IMP clients with hydrophobic faces and a minimal length of 11 residues. This work places Sgt2 into a broader family of TPR-containing co-chaperone proteins

Excitation Function Measurements of Proton Induced Reactions on Rhodium and Indium: Yields of 97-Ru, 96-Tc, 109-Cd, and 113-Sn

Supported by the National Science Foundation and Indiana Universit

Excitation Function Measurements of Proton Induced Reactions on Rhodium and Indium: Yields of Ru-97, Tc-96, Cd-109, and Sn-113

This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit

An investigation of angular stiffness and damping coefficients of an axial spline coupling in high-speed rotating machinery

This paper provided an opportunity to quantify the angular stiffness and equivalent viscous damping coefficients of an axial spline coupling used in high-speed turbomachinery. A unique test methodology and data reduction procedures were developed. The bending moments and angular deflections transmitted across an axial spline coupling were measured while a nonrotating shaft was excited by an external shaker. A rotor dynamics computer program was used to simulate the test conditions and to correlate the angular stiffness and damping coefficients. In addition, sensitivity analyses were performed to show that the accuracy of the dynamic coefficients do not rely on the accuracy of the data reduction procedures

Three-dimensional virtual reality in surgical planning for breast cancer with reconstruction

Breast surgery is performed to achieve local control in patients with breast cancer. Visualization of the anatomy with a virtual reality software platform reconstructed from magnetic resonance imaging data improves surgical planning with regards to volume and localization of the tumor, lymph nodes, blood vessels, and surrounding tissue to perform oncoplastic tissue rearrangement. We report the use and advantages of virtual reality added to the magnetic resonance imaging assessment in a 36-year-old woman with breast cancer who underwent nipple sparing mastectomy with tissue expander reconstructio