7-ray burst

O/C ratio. The observed and predicted variations with Z of the number ratio of SNIb/c and SNII shows an interesting agreement [11]. This is noticeable because of the possible connection WO stars - SNIb/c - GRBs (7 Ray Bursts). In this context, we consider WO stars as good candidate for GRB progenitors. 

If tau neutrinos emitted from SN1987A decayed outside the star, the 7-ray burst following the //-burst could be expected. Therefore observation of the /-ray burst from SN1987A imposes a strict... 

These stars have been of central concern in a myriad of observational and theoretical works. No wonder They indeed play a key role in many chapters of astrophysics. In particular, they influence the physical and chemical states of their circumstellar environments or of the interstellar medium through their intense radiation and mass losses during their non-explosive phases of evolution, and even more so, as a result of their final supernova explosions. They may act as triggers of star formation, are essential agents of the evolution of the nuclidic content of the galaxies, accelerate particles to cosmic ray energies, and leave neutron stars or black holes at the end of their evolution. They are also the progenitors of certain 7-ray bursts. 

The origin of X-rays, 7-ray bursts and radiowaves that pervade the Galaxy is as mysterious as the cosmic-ray sources. Evidence is mounting that in most cases these phenomena are linked to violent explosions, thought to include neutron-star quakes, quark nuggets, supernovae, matter-antimatter annihilation, clumping of quasars and colliding stars. Of all space radiations radio phenomena have been studied in most detail. 

D.Yu. Tsvetkov, S.I. Blinnikov, N.N. Pavlyuk (2001). Gamma-ray Bursts, Type Ib/c Su-pemovae and Star-forming Sites in Host Galaxies , Astronomy Letters, v.27, issue 7, pp.411-415. 

Nanosecond time-resolved crystallography of MbCO has been discussed in Section 3.7.2.3 of Chapter 3.46 After firing a 10-ns burst of laser light to break the CO-Fe bond, these researchers produced a diffraction image of the crystal through application of a 150-ps X-ray pulse. They are able to show release of the CO molecule, displacement of the Fe ion toward the proximal histidine, and recombination of the dissociated CO by about 100 ps. Essentially their results compare well with other spectroscopic studies of HbCO, MbCO and their models. 

X-ray absorption furnishes an absolute measure of the density of matter. However, in many applications the important observations to be made with X-rays concern the geometrical relationships of shock fronts and contact surfaces it is in this area where X-rays, because they make it possible to sefe inside the detonating expl, provide a uniquely appropriate tool. Until recently the difficulty has been the inability of available sources to penetrate charges more than a few inches in diameter. With the advent of the PHERMEX machine this difficulty has been overcome. Phermex provides a pulsed beam of 27 Me V electrons in 0.1 microsec bursts, which impinge on a tungsten target to generate X-rays that can easily penetrate several cm of HE. Recall that density of the shocked material can be related to particle velocity thru the conservation equations (see Vol 7, HI 79)... 

Small molecules modulating microtubule assembly have played major roles as tools in microtubule research, in a manner closely related to their chemotherapeutic interest [1], Tubulin was first purified in the last century as the colchicine-binding protein proposed to be the subunit of cellular microtubules [2], More recently, a colchicine derivative was employed to help crystallization and determine the structure of tubulin by X-ray diffraction [3], The colchicine, vinblastine [4] and paclitaxel [5] sites are main drug binding sites of tubulin, to which many other substances bind. The discovery of microtubule stabilization by paclitaxel [6] prompted its clinical development [7] and a burst of research on new MSAs, as well as the generalized use of paclitaxel or docetaxel as convenient reagents to assemble (see Fig. 1), stabilize or detect microtubules in the laboratory. One example is the development... 

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