The synthesis of water soluble decalin-based thiols and S-nitrosothiols--model systems for studying the reactions of nitric oxide with protein thiols

The syntheses of three decalin-based tert-thiols displaying varying degrees of solubility in aqueous milieu are described. The S-nitroso derivatives of these compounds have also been prepared and the structures of two of these determined by single crystal X-ray diffraction. These compounds have been designed for studying the interaction of nitric oxide (NO) with thiols under physiological conditions.     

Synthesis of 1,1-dichloro-2,2-bis(4-hydroxyphenyl)-ethylene via ammonia or methylamine dehydrochlorination. A bisphenol for the preparation of highly flame-resistant polycarbonates

Ammonia used as both reactant and solvent has been shown to dehydrochlorinate 1,1,1-tri-chloro-2,2-bis(4-hydroxyphenyl)ethane smoothly to 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene. The reaction is complete in 1 hr at 100°C, and after two crystallizations from methanol/water affords polymerizable quality monomer for the synthesis of highly flame-resistant polycarbonates. The use of organic solvents in combination with ammonia does not offer any rate advantages over pure ammonia. Primary and secondary amines also can be used to effect the dehydrochlorination but, except for the methylamine, are significantly less reactive and lead to less pure product than amonia.     

A DYE LASER SOURCE OF MONOCHROMATIC UV-B and UV-C RADIATIONS FOR BIOLOGICAL ACTION SPECTROSCOPY

Abstract We have used a flashlamp driven tunable dye laser as a radiation source for observing UV-C and UV-B action spectra of two eukaryotic microorganisms. The general nature of the irradiation system and various operating parameters are described. The laser produces the high power output required for UV-B action spectroscopy; it is tunable throughout the UV-B range with the very narrow bandwidth required for high resolution action spectra. The peak power density does not appear to reach the threshold of 'two photon' biological effects, a concern when using pulsed lasers for action spectroscopy. The laser is somewhat more expensive and considerably more difficult to operate compared with arc-monochrometer systems; it is generally equal or greater in UV-B power and has distinct advantages in tunability and bandwidth of the spectral output.     

A comparison of the production of K (890) in Kp and Kp interactions

Results are presented on an analysis of the reaction K⁺p → K^∗+ (890) p at 16 GeV/c and compared with data at lower incident momenta and with corresponding results for the reaction K⁻p → K^∗− (890) p. It is found for both reactions that the energy dependence of the cross section exhibits a simple (p⁻ⁿ_lab behaviour.     

Synthesis of 1,2,3,12a,12b‐Hexahydrocyclopropa‐[1,2‐d]benzo[f]pyrrolo[1,2‐b]isoquinolin‐5,7‐dione related to duocarmycins and anthramycin

Structural features of the Duocarmycins and Anthramycin were incorporated into 1,2,3,12a,12b‐hexahydro‐cyclopropa[1,2‐d]benzo[f]pyrrolo[1,2‐b]isoquinolin 5,7‐dione. The synthesis of the cis and trans diastereomers was accomplished using a benzyne Diels‐Alder reaction and an imine‐anhydride cyclization as key steps.     

Tangential Quantum Cohomology of Arbitrary Order

Kock has previously defined a tangency quantum product on formal power series with coefficients in the cohomology ring of any smooth projective variety, and thus a ring that generalizes the quantum cohomology ring. We further generalize Kock's construction by defining a dth-order contact product and establishing its associativity.     

Brain-derived neurotrophic factor modulation of Kv1.3 channel is disregulated by adaptor proteins Grb10 and nShc

Background

Developmental dyslexia is a specific cognitive disorder in reading acquisition that has genetic and neurological origins. Despite histological evidence for brain differences in dyslexia, we recently demonstrated that in large cohort of subjects, no differences between control and dyslexic readers can be found at the macroscopic level (MRI voxel), because of large variances in brain local volumes. In the present study, we aimed at finding brain areas that most discriminate dyslexic from control normal readers despite the large variance across subjects. After segmenting brain grey matter, normalizing brain size and shape and modulating the voxels' content, normal readers' brains were used to build a 'typical' brain via bootstrapped confidence intervals. Each dyslexic reader's brain was then classified independently at each voxel as being within or outside the normal range. We used this simple strategy to build a brain map showing regional percentages of differences between groups. The significance of this map was then assessed using a randomization technique.

Results

The right cerebellar declive and the right lentiform nucleus were the two areas that significantly differed the most between groups with 100% of the dyslexic subjects (N = 38) falling outside of the control group (N = 39) 95% confidence interval boundaries. The clinical relevance of this result was assessed by inquiring cognitive brain-based differences among dyslexic brain subgroups in comparison to normal readers' performances. The strongest difference between dyslexic subgroups was observed between subjects with lower cerebellar declive (LCD) grey matter volumes than controls and subjects with higher cerebellar declive (HCD) grey matter volumes than controls. Dyslexic subjects with LCD volumes performed worse than subjects with HCD volumes in phonologically and lexicon related tasks. Furthermore, cerebellar and lentiform grey matter volumes interacted in dyslexic subjects, so that lower and higher lentiform grey matter volumes compared to controls differently modulated the phonological and lexical performances. Best performances (observed in controls) corresponded to an optimal value of grey matter and they dropped for higher or lower volumes.

Conclusion

These results provide evidence for the existence of various subtypes of dyslexia characterized by different brain phenotypes. In addition, behavioural analyses suggest that these brain phenotypes relate to different deficits of automatization of language-based processes such as grapheme/phoneme correspondence and/or rapid access to lexicon entries.     

Cross sections for charged current ν and\bar v interactions in the energy range 10 to 50 GeV

Charged-current neutrino and antineutrino interaction cross sections have been measured in the energy range 10 to 50 GeV using BEBC filled with a neon-hydrogen mixture. At these energies, σ/E was measured to be (0.73±0.08) 10^?38 cm²/GeV per nucleon for neutrinos and (0.32±0.06) 10^?38 cm²/GeV per nucleon for antineutrinos.     

A study of resonance production in the reaction K+p → K0pπ+ from 3 to 16 GeV/c

The reactions $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{1+}}\text{(890)}\text{p}$, $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{1+}}\text{(1420)}\text{p}$ and K⁺p → K⁰Δ⁺⁺ have been systematically studied for eleven incident momenta between 3.0 and 16.0 GeV/c. Cross sections, differential cross sections and density matrix elements are presented. For K¹(890) production the contributions from natural and unnatural parity exchanges have also been separated into I = 0 and I = 1 components. Effective trajectories have been extracted in the case of natural parity exchange, and also for Δ⁺⁺ production.