Flow separation detectors and, more particularly feedback sensor arrangements consisting of optical fiber tufts adapted to provide for the measurement of surface aerodynamic flow phenomena through the effects birefringence or transmitted light, and especially with regard to aerodynamic flow separation which is encountered over a surface. The sheet ejecting device includes a sheet stacking section; a bumping section; a sheet ejecting section; a mode selecting section; and a control section. The spring end portions engage the mounting box to bias the shanks into their coupled position. Additionally, the pivot pins and holes can hold the rack steady at a desired angle. The methods may also allow improving glycemic control of type II diabetes patients andor reducing side effects andor cardiovascular risks of antidiabetic agents. Anti-shivering mechanisms and automatic control based on temperature feedback from the patient may be used in connection with the heat exchange system.