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81.
Zacharias Kohl Martin Regensburger Robert Aigner Mahesh Kandasamy Beate Winner Ludwig Aigner Jürgen Winkler 《BMC neuroscience》2010,11(1):114
Background
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder linked to expanded CAG-triplet nucleotide repeats within the huntingtin gene. Intracellular huntingtin aggregates are present in neurons of distinct brain areas, among them regions of adult neurogenesis including the hippocampus and the subventricular zone/olfactory bulb system. Previously, reduced hippocampal neurogenesis has been detected in transgenic rodent models of HD. Therefore, we hypothesized that mutant huntingtin also affects newly generated neurons derived from the subventricular zone of adult R6/2 HD mice. 相似文献82.
Direct arylation of the exocyclic amino groups of nucleosides represents a simple approach to N-aryl nucleoside derivatives. To date, one limitation has been that only electron-deficient aryl bromides and triflates possessed adequate reactivity for efficient, direct N-arylation of nucleosides. We demonstrate herein that Pd-Xantphos catalytic systems lead to successful N-arylation of suitably protected 2'-deoxyadenosine and 2'-deoxyguanosine with a wide range of aryl bromides. 相似文献
83.
The Twentieth NSRRC Users' Meeting was held successfully at the National Synchrotron Radiation Research Center (NSRRC) in Taiwan from September 10th to 12th, 2014. The three-day meeting was the first such event to be held at the newly furnished Activity Center on the NSRRC campus, celebrating 20 years since the first NSRRC Users' Meeting and highlighting the prospective scientific frontiers marked by the newly established Taiwan Photon Source (TPS) storage ring. 相似文献
84.
ABSTRACTZnTe (Zinc Telluride) is a potential semiconducting material for many optoelectronic devices like solar cells and back contact material for CdTe-based solar cells. In the present study, ZnTe thin films were prepared by thermal evaporation technique and then irradiated with 120?MeV Si9+ ions at different fluences. These films are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–Visible spectroscopy techniques. XRD study confirms increased crystallinity and grain growth for post-irradiated ZnTe thin films for fluences, up to 1?×?1011 ions cm?2. However, the grain size and crystallinity decreased for higher fluence-exposed samples. SEM images confirm the observed structural properties. Modification of the surface morphology of the film due to the ion irradiation with different fluences is studied. Optical band gap of film is decreased from 2.31?eV (pristine) to 2.17?eV after irradiation of Si9+ ions. 相似文献
85.
Puchakayala Bharath Kumar Reddy Kanakaraju Ravi Kukkamudi Mahesh Panaganti Leelavathi 《Tetrahedron letters》2018,59(45):4039-4043
A simple and convenient sequential one-pot synthesis of 1,2,3,4-tetrahydrobenzo[b][1,6] naphthyridines has been developed. The reductive amination of 2-chloro-3-formylquinolines with various amines in the presence of sodium borohydride provided the corresponding secondary amines in high yields. Further, a sequential one-pot reaction involving N-allylation and intramolecular Heck type 6-exo-trig cyclization was performed on the secondary amines to afford a range of desired 1,2,3,4-tetrahydrobenzo[b][1,6]-naphthyridine derivatives in good to high yields. 相似文献
86.
Patil SP Mathew R Ajithkumar TG Rajamohanan PR Mahesh TS Kumaraswamy G 《The journal of physical chemistry. B》2008,112(15):4536-4544
We describe the covalent modification of the edges of laponite with organic groups and the influence of this modification on gelation behavior. We compare three materials: an unmodified laponite, a laponite edge modified with a trimethyl moiety (MLap), and an octyldimethyl moiety (OLap). Gelation is investigated using rheology and NMR T1 relaxation measurements and nuclear Overhauser enhancement spectroscopy (NOESY). MLap and OLap show qualitatively different gelation. Gelation of MLap is very similar to laponite: MLap gels over the same time scale as laponite and has about the same solid modulus, and the MLap gel is almost as transparent as laponite. In contrast, OLap gels rapidly relative to laponite and forms a weak, turbid gel. We believe that gelation in laponite and MLap results from the formation of a network of well-dispersed platelets (or a few platelets), while in OLap, gelation results from a network of stacks of several platelets. NMR relaxation measurements indicate that gelation does not affect the average relaxation of water protons. However, T1 increases marginally for the protons in the organic moieties in MLap and decreases for protons in the organic moieties in OLap. Relaxation measurements, analyses of line width, and NOESY taken together suggest that, in OLap, gelation is a consequence of association of the organic moieties on the laponite edges, and that this association strengthens with time. Thus, the time-dependent changes in NMR suggest a structural origin for the time-dependent changes in the rheological behavior. 相似文献
87.
Avinash S. Kumbhar Mahesh P. Mulay Subhash B. Padhye Sudam S. Tavale Vedavati G. Puranik 《Structural chemistry》2008,19(5):735-740
Crystal structure of {[Mn(salicylaldoximeH)(salicylaldoxime)]4} · 3CHCl3 1 formed by the interaction of MnCl2 · 4H2O and salicylaldoxime in a 1:1 ratio is described. The compound crystallizes in the orthorhombic space group Pbca (No 61) with the lattice parameters; a = 27.769 (3), b = 22.672 (2), c = 21.650 (2) Å, V = 13630 (2) Å3, Z = 8, R 1 = 0.0776, wR 2 = 0.2356, S = 1.164. The cluster with four Mn (III) centers formed by four terminal and four bridging salicylaldoxime ligands results in a central rotating wheel-like core with the Mn–Mn separation varying from 3.531 to 3.576 Å and with the diagonal distances being 4.156–4.165 Å. Four intramolecular H-bonds between a terminal oxime (NOH) group and the adjacent phenolate oxygen atom of another ligand stabilize the structure of the cluster. Spectral, magnetic, and cyclic voltammetry studies corroborate a stable Mn (III) tetramer. 相似文献
88.
Huan Wang Dr. Mahbod Morshedi Dr. Mahesh S. Kodikara Dr. Yovan de Coene Prof. Koen Clays Prof. Chi Zhang Prof. Mark G. Humphrey 《Angewandte Chemie (International ed. in English)》2023,62(27):e202301754
Porphyrins are important macrocycles with applications in several areas including therapy, catalysis, and sensing. Strong nonlinear optical (NLO) responses are the key to fully exploiting the potential of these biocompatible molecules. We herein report that certain metal-alkynyl donor/nitro acceptor-functionalized porphyrins are attractive candidates for NLO applications. We show that specific examples exhibit record quadratic optical nonlinearity, exceptional two-photon absorption, and outstanding three-photon absorption, and we report the first porphyrins that exhibit four-photon absorption. The two-, three-, and four-photon absorption maxima are found at the corresponding multiples of linear absorption bands that time-dependent density functional theory assigns as admixtures of porphyrin-localized π*←π and donor-porphyrin to porphyrin-acceptor charge-transfer transitions. 相似文献
89.
Mahesh Kalidasan S. Sangilipandi R. Nagarajaprakash K. Mohan Rao 《Transition Metal Chemistry》2016,41(3):261-270
The reactions of [(arene)RuCl2]2 (arene = p-cymene or benzene) and [Cp*MCl2]2 (M = Rh or Ir) with N,N′-bidentate chelating ligands 2-[3-(2-pyridyl)pyrazolyl]pyrimidine (L1) and 4-phenyl-(2-pyridyl)thiazole (L2) leads to the formation of mononuclear complexes of general formula [(arene)/Cp*M(L)Cl]PF6. Eight such complexes have been prepared and characterized by spectroscopic techniques. In addition, five of the complexes were also characterized by single-crystal X-ray diffraction. These complexes have typical piano-stool geometries around the metal center, with five-membered metellacycles in which L1 and L2 both act as N,N′-chelating ligands. Moreover, L1 prefers to coordinate through its pyrimidine and pyrazolyl nitrogen atoms, rather than the pyridine nitrogen. 相似文献
90.
M.L.V. Mahesh V.V. Bhanu Prasad A.R. James 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(4):108
Barium zirconium titanate, Ba(Zr0.15Ti0.85)O3 nano-crystalline powders were synthesized using highenergy ball milling. The calcined powders were compacted adopting two different approachesviz. the conventional uniaxial pressing and cold-isostatic pressing (CIP) and the compactswere sintered at 1350 °C. Asingle phase perovskite structure was observed in both cases. BZT ceramics compacted usingCIP technique exhibited enhanced dielectric and ferroelectric properties compared toceramics compacted by uniaxial pressing. The polarization current peaks have been used inthis paper as an experimental evidence to prove the existence of ferroelectricity in theBZT ceramics under study. The peak polarization current was found to be ~700% higher in case of coldiso-statically compacted ceramics. Similarly electric field induces strain showed amaximum strain (Smax) of 0.08% at an electric fieldof 28 kV/cm. The dielectric and ferroelectric properties observed are comparable to singlecrystals of the same material. 相似文献