1. The effect of y-irradiation in the range 1 krad-10 Mrads on freeze-dried acid-soluble collagen was studied. 2. The specific-rotation and reduced-viscosity recoveries after heating and cooling of the irradiated collagen in solution showed a high degree of dependence on irradiation dose, with reduced viscosity showing significantly less recovery than specific rotation on increasing the irradia...

Circular dichroism (CD) data are reported of a series of 9,10stereoisomeric steroidal 5,7-dienes. In general the effects in the longest wavelength transition (270-280 nm) are large (Mm" 10---30) and consignate with respect to the diene helicity rule. The magnitude of the CD appears to vary markedly with the substituent at C-3 and at C-17, and with solvent. In the case of the 9a,10p-H dienes, va...

The low-frequency peaked BL Lac (LBL) object BL Lacertae was observed with the MAGIC telescope from 2005 August to December (22.2 hr), and from 2006 July to September (26.0 hr). A very high energy (VHE) γ-ray signal was discovered with a 5.1 σ excess in the 2005 data. Above 200 GeV, an integral flux of (0.6± 0.2) × 10 cm s was measured, corresponding to approximately 3% of the Crab flux. The di...

From the branches of Microtropis japonica (Celastraceae), seven phenolic alcohol glucosides, named microtropins J-P (1-7), were isolated. The 6-position of glucose was esterified with 2-ethyl-2,3-dihydroxybutyric acid. Microtropin K (2) was hydrolyzed under a mild basic condition to give methyl (2S,3R)-2-ethyl-2,3-dihydroxybutyrate, whose absolute structure was determined by the comparison of N...

A VLA survey of nearby LINER galaxies at 15 GHz has revealed the presence of a compact radio core in many sources. The cores seem to be correlated with the optical activity. Follow-up VLBA observations of the ten brightest sources confirm that these cores have brightness temperatures> 10 Kelvin, thus confirming their AGN nature. The two brightest radio sources show extended jet-like structures ...

We consider an agricultural production problem, in which one must supply a given demand of crops while respecting ecologically-based production constraints. The problem is twofold: in order to supply the demand, one must determine the division of the available heterogeneous arable areas in plots and, for each plot, obtain an appropriate crop rotation schedule. Rotation plans must respect ecolog...

An angular displacement-enhanced heterodyne polarimeter has been employed to investigate the interplay between trifluoroethanol (TFE) and glycerol on the thermal denaturation of type I collagen. The concentration of the collagen solution was fixed at 0.341 (mg/mL), and was heated from 25 °C to 55 °C. TFE solutions with concentrations of 5%, 10%, 15%, 20%, 40% and 80% (v/v) were prepared and the...

Antirelaxation surface coatings allow long spin relaxation times in alkali-metal cells without buffer gas, enabling faster diffusion of the alkali atoms throughout the cell and giving larger signals due to narrower optical linewidths. Effective coatings were previously unavailable for operation at temperatures above 80 °C. We demonstrate that octadecyltrichlorosilane OTS can allow potassium or ...

The identification of a universal biosignature that could be sensed remotely is critical to the prospects for success in the search for life elsewhere in the universe. A candidate universal biosignature is homochirality, which is likely to be a generic property of all biochemical life. Due to the optical activity of chiral molecules, it has been hypothesized that this unique characteristic may ...

The kinematic flexibility of frog hindlimbs enables multiple locomotor modes within a single species. Prior work has extensively explored maximum performance capacity in frogs; however, the mechanisms by which anurans modulate performance within locomotor modes remain unclear. We explored how Kassina maculata, a species known for both running and jumping abilities, modulates takeoff angle from ...