Randomisation density

Atkinson C, Compston JE, Day NE, Dowsett M, Bingham SA. The effects of phytoestrogen isoflavones on bone density in women a double-blind, randomised, placebo-controlled trial. Am. J. Clin. Nutr. 79, 326-333, 2004. 

Tattersfield AE, Town GI, Johnell O, Picado C, Aubier M, Braillon P, Karlstrom R. Bone mineral density in subjects with mild asthma randomised to treatment with inhaled corticosteroids or non-corticosteroid treatment for two years. Thorax 2001 56(4) 272-8. 

The rates of losses of C3(H, D)6 from the molecular ions of phenyl-1-propyl-1, l-d2, phenyl-l-propyl-2, 2-dj and phenyl-1-propyl-3, 3, 3-d3 ether showed that hydrogen randomisation did not precede decomposition in the time range from 10ps to 10 ps [86], The losses were initiated by hydrogen transfers from C-l, C-2 or C-3 of the propyl chain to the oxygen atom and, on the basis of the kinetics, it was suggested that the densities of states of the 4-, 5- and 6-membered cyclic transition states were similar. 

A similar study involving 18 postmenopausal women with PBC looked at the safety and efficacy of transdermal HRT over a two-year period. The women were randomised to receive calcium and alfacalci-dol either alone or in combination with HRT (oestradiol and medroxyprogesterone). A significant increase in bone mineral density in the lumbar spine and femoral neck was seen in the group receiving HRT... 

Frohlich (1947) based his calculations on the hypothesis of the energy-level scheme shown in Fig. 6.1, where conduction electrons are derived from impurity levels lying deep (V = 1 eV or more) in the forbidden zone. There is also a set of shallow traps spread below the conduction-band edge (F> AF> kT). In outline, the theory of breakdown is then as follows. In an applied electric field E, energy is transferred directly to the conduction electrons (charge e, mass m) at a rate A = jE, where j is the current density. If we suppose that each electron is accelerated in the field direction for an average time 2r between collisions at which its energy is completely randomised, then the mean drift velocity of the conduction electrons in the field direction... 

Figure 1. Simulated isotherms for models of G3. adsorption x desorption (uniform porosity) o desorption (randomised pore size, uniform porosity) + desorption (spin density image porosity). Macroscopic model pore size allocated from T, image except where stated.

Coleman, R.E., Banks, L.M., Girgis, S.I., Kilbum, L.S., Vrdoljak, E Fox, J., Cawthom, S.J., Patel, A., Snowdon, C.F., Hall, E., Bliss, J.M. and Coombes, R.C. (2007) Skeletal effects of exemestane on bone-mineral density, bone biomarkers, and fracture incidence in postmenopausal women with early breast cancer participating in the Intergroup Exemestane Study (IES) a randomised controlled study. The Lancet Oncology, 8, 119-127. 

The Medical Research Council s General Practice Research Eramework (1998) Thrombosis Prevention Trial Randomised Trial of Low-Density Oral Anticoagulation with Warfarin and Low-Dose Aspirin in the Primary Prevention of Ischaemic Heart Disease in Men at Increased Risk, Lancet 351,233-241. 

These values of the first and second order randomisation rate constants do not seem unreasonable. The values for /ij are about the same for both molecules, and are close to the generally accepted estimate of around 10 s" for intramolecular randomisation processes [82.T]. No previous estimates have been made for second order randomisation rate constants, but it seems plausible that they might increase with increasing state density, as we find here the density of states near threshold is about six or seven times greater in the deuteriated as opposed to the normal methyl... 

On the theoretical front, it is possible to make a few simple assertions. We have already seen that a collisional component to the randomisation process may become faster the more dense are the states of the molecule. It is also obvious that the first order component will become slower as the states become further apart, but the molecular level density where this begins is not known a cut-off at about 1000 states per wavenumber has been suggested [82.S2] for intramolecular vibrational relaxation of isolated molecules in one kind of experiment. It is also obvious that there must be propensity rules for the occurrence of randomising transitions within any grain [81.P2] for example, transitions between states of... 

Musculoskeletal In a double-blind, placebo-controlled trial, 71 subjects were randomised to rosiglitazone or placebo for 48 weeks. Rosiglitazone has been associated with decreased bone formation, but total bone mineral density did not change significantly in either group. [66 ]... 

In a 52-week, double-blind, randomised study, 226 postmenopausal women with type 2 diabetes received therapy with rosiglitazone 4 mg daily. Rosiglitazone was associated with small reductions in bone mineral density in e femoral neck, total hip, and lumbar spine with increased bone turnover markers. [67 ... 

Randomised trials A randomised, controlled trial of 6 months of parathyroid hormone treatment in combination with either concurrent or sequential ibandronate over 2 years [67 ] found that both treatment regimens were efficacious in increasing bone mineral density in postmenopausal women (N = 44). Seven women met the criteria for hypercalcaemia, with only one requiring reduction in treatment. Three women met the criteria for hypercalciuria. The most commonly reported adverse events were nausea (32%) and injection-site reactions (32%). 

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