34,026 research outputs found
Ligand-Specific Regulation of the Endogenous Mu-Opioid Receptor by Chronic Treatment with Mu-Opioid Peptide Agonist
No full textSince the discovery of the endomorphins (EM), the postulated endogenous peptide agonists of the mu-opioid receptors, several analogues have been synthesized to improve their binding and pharmacological profiles. We have shown previously that a new analogue, cis-1S,2R-aminocyclohexanecarboxylic acid2-endomorphin-2 (ACHC-EM2), had elevated mu-receptor affinity, selectivity, and proteolytic stability over the parent compound. In the present work, we have studied its antinociceptive effects and receptor regulatory processes. ACHC-EM2 displayed a somewhat higher (60%) acute antinociceptive response than the parent peptide, EM2 (45%), which peaked at 10 min after intracerebroventricular (icv) administration in the rat tail-flick test. Analgesic tolerance developed to the antinociceptive effect of ACHC-EM2 upon its repeated icv injection that was complete by a 10-day treatment. This was accompanied by attenuated coupling of mu-sites to G-proteins in subcellular fractions of rat brain. Also, the density of mu-receptors was upregulated by about 40% in the light membrane fraction, with no detectable changes in surface binding. Distinct receptor regulatory processes were noted in subcellular fractions of rat brains made tolerant by the prototypic full mu-agonist peptide, DAMGO, and its chloromethyl ketone derivative, DAMCK. These results are discussed in light of the recently discovered phenomenon, that is, the “so-called biased agonism” or “functional selectivity
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Laser-light-absorption studies at 1. 06. mu. m, 0. 53. mu. m, and 0. 35. mu. m wavelengths
No full textResults are presented of light absorption in a series of wavelength scaling experiments recently completed at LLNL. The Argus facility was used to do target studies at 1.06..mu..m, 0.53..mu..m and 0.35..mu..m. Box calorimeter scattered light measurements implied greatly improved laser light absorption for both high Z and low Z plasmas at laser wavelengths shorter than 1.06..mu..m. Furthermore, at the 0.35..mu..m laser wavelength, the inferred absorption is nearly 100% over a substantial range of incident laser intensities. Our results further show a dramatic decrease in the stimulated Brillouin scattered light at 0.35..mu..m relative to the values at 1.06..mu..m and 0.53..mu..m
THE REACTIONS OF DIOXOBIS(ACETYLACETONATO)MOLYBDENUM, MOO2(ACAC)2, WITH TETRATHIOMOLYBDATE AND TETRATHIOTUNGSTATE - HIGH FORMATION TENDENCY OF THE (MVI(MU-S)2MOIVO(MU-S)2MVI) GROUP AND THE [MVIS3(S2)]2- TYPE LIGAND (M = MO, W)
No full textHerberhold M, Jin GX, Müller A, Penk M. THE REACTIONS OF DIOXOBIS(ACETYLACETONATO)MOLYBDENUM, MOO2(ACAC)2, WITH TETRATHIOMOLYBDATE AND TETRATHIOTUNGSTATE - HIGH FORMATION TENDENCY OF THE (MVI(MU-S)2MOIVO(MU-S)2MVI) GROUP AND THE [MVIS3(S2)]2- TYPE LIGAND (M = MO, W). ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES. 1991;46(1):25-34.Tetraphenylphosphonium tetrathiometalates, (PPh4)2MS4 (M = Mo, W), react with MoO2(acac)2 (2:1) in boiling acetonitrile in redox processes to give mixed-crystal compounds (as expected) of the approximate composition (PPh4)2[Mo3O1.9S8.1] (1) and (PPh4)2[Mo1.4W1.6O1.3S8.3] (2), respectively. 1 and 2 were characterized by single crystal X-ray structure analyses. The various anions of 1 and 2 contain {M(VI)(mu-S)2Mo(IV)O(mu-S)2M(VI)} cores (M = Mo (1); Mo, W (2); bond angle M...Mo...M = 151.3-degrees (1), 152.2-154.3-degrees (2)), which have high formation tendencies. The terminal positions are occupied by S and O atoms. The trinuclear anions of 1 correspond to the type [XYMo(mu-S)2MoO(mu-S)2MoSX]2- (X = O, S; Y = S, S2). In 2 there are two sets of anions of the type [XYM(mu-S)2MoO(mu-S)2WS2]2- and [ZSM(mu-S)2MoO(mu-S)2MZS]2- (Z = S(n)/O(m)) in the ratio of 2:1, occupying two symmetry-independent sites in the unit cell. Complex 2 is the first structurally characterized mixed-metal Mo-W thiometalate
Search for in the gauge-symmetric model at Belle
No full textWe search for a new gauge boson that couples only to heavy leptons and their corresponding neutrinos in the process , using a 643 fb data sample collected by the Belle experiment at or near the resonances at the KEKB collider. For the first time, effects due to initial state radiation are used in estimating the detection efficiency. No signal is observed in the mass range of and we set an upper limit on the coupling strengh, , constraining as a possible contributor to the anomalous magnetic dipole moment of muon
Characterization of Scuba-2 450 mu m and 850 mu m selected galaxies in the COSMOS field
No full textInternational audienceWe present deep 450 mu m and 850 mu m observations of a large, uniformly covered 394 arcmin(2) area in the Cosmic Evolution Survey (COSMOS) field obtained with the Scuba-2 instrument on the James Clerk Maxwell Telescope (JCMT). We achieve root-mean-square noise values of Sigma(450) = 4.13 mJy and Sigma(850) = 0.80 mJy. The differential and cumulative number counts are presented and compared to similar previous works. Individual point sources are identified at \textgreater 3.6 Sigma significance, a threshold corresponding to a 3-5 per cent sample contamination rate. We identify 78 sources at 450 mu m and 99 at 850 mu m, with flux densities S-450 = 13-37 mJy and S-850 = 2-16 mJy. Only 62-76 per cent of 450 mu m sources are 850 mu m detected and 61-81 per cent of 850 mu m sources are 450 mu m detected. The positional uncertainties at 450 mu m are small (1-2.5 arcsec) and therefore allow a precise identification of multiwavelength counterparts without reliance on detection at 24 mu m or radio wavelengths; we find that only 44 per cent of 450 mu m sources and 60 per cent of 850 mu m sources have 24 mu m or radio counterparts. 450 mu m selected galaxies peak at \textless\textless z \textgreater\textgreater = 1.95 +/- 0.19 and 850 mu m selected galaxies peak at \textless\textless z \textgreater\textgreater = 2.16 +/- 0.11. The two samples occupy similar parameter space in redshift and luminosity, while their median SED peak wavelengths differ by similar to 20-50 mu m (translating to delta T-dust = 8-12 K, where 450 mu m selected galaxies are warmer). The similarities of the 450 mu m and 850 mu m populations, yet lack of direct overlap between them, suggests that submillimetre surveys conducted at any single far-infrared wavelength will be significantly incomplete (greater than or similar to 30 per cent) at censusing infrared-luminous star formation at high z
The ALMA REBELS Survey:Average [C ii] 158 mu m Sizes of Star-forming Galaxies from z similar to 7 to z similar to 4
No full textWe present the average [C ii] 158 mu m emission line sizes of UV-bright star-forming galaxies at z similar to 7. Our results are derived from a stacking analysis of [C ii] 158 mu m emission lines and dust continua observed by the Atacama Large Millimeter/submillimeter Array (ALMA), taking advantage of the large program Reionization Era Bright Emission Line Survey. We find that the average [C ii] emission at z similar to 7 has an effective radius r ( e ) of 2.2 +/- 0.2 kpc. It is greater than or similar to 2x larger than the dust continuum and the rest-frame UV emission, in agreement with recently reported measurements for z less than or similar to 6 galaxies. Additionally, we compared the average [C ii] size with 4 < z < 6 galaxies observed by the ALMA Large Program to INvestigate [C ii] at Early times (ALPINE). By analyzing [C ii] sizes of 4 < z < 6 galaxies in two redshift bins, we find an average [C ii] size of r (e) = 2.2 +/- 0.2 kpc and r (e) = 2.5 +/- 0.2 kpc for z similar to 5.5 and z similar to 4.5 galaxies, respectively. These measurements show that star-forming galaxies, on average, show no evolution in the size of the [C ii] 158 mu m emitting regions at redshift between z similar to 7 and z similar to 4. This finding suggests that the star-forming galaxies could be morphologically dominated by gas over a wide redshift range.</p
Estimation of evapotranspiration in the Mu Us Sandland of China
No full textEvapotranspiration (ET) was estimated from 1981–2005 over Wushen County located in the Mu Us Sandland, China, by applying the Advection-Aridity model, which is based on the complementary relationship hypothesis. We used National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS), and meteorological data. Our results show that the estimated daily ET was about 4.5% higher than measurements using an Eddy Covariance (EC) system after forcing energy balance closure over an alfalfa field from 22 July 2004 to 23 August 2004. At a regional scale, the estimated monthly ET was about 8.7% lower than measurements using the EC system after forcing energy balance closure over an alfalfa field in August 2004. These results were about 3.0% higher than ET measurements by microlysimeter over sand dunes during June 1988. From 1981 to 2005, the average annual ET and precipitation levels were 287 mm and 336 mm, respectively, in Wushen County. The average annual ET varied from 230 mm in western parts of Wushen County to 350 mm in eastern parts of the county. Both inter-annual and seasonal variations in ET were substantial in Wushen County. The annual ET was 200–400 mm from 1981–2005, and the seasonal pattern of ET showed a single peak distribution. The cumulative ET during the June–September 2004 period was 250 mm, which was 87% of the total annual ET. The annual ET, precipitation, and the maximum Normalized Difference Vegetation Index (NDVI<sub>max</sub>) showed positive correlations temporally and spatially
New type of polymeric indium tellurides: Low-temperature synthesis and structure characterization of [M(en)(3)]In2Te6 (M=Fe, Zn) and alpha- and beta-[Mo-3(en)(3)(mu(2)-Te-2)(3)(mu(3)-Te)(mu(3)-O)]In2Te6
No full textCrystal growth of metal tellurides and tellurometalates employing solvothermal reactions at temperatures below 200 degrees C have resulted in four new indium tellurium phases, [Fe(en)(3)](In2Te6) (I), [Zn(en)(3)](In2Te6) (II), and alpha- and beta-[Mo-3(en)(3)(mu(2)-Te-2)(3)(mu(3)-Te)(mu(3)-O)]In2Te6 (III-alpha and III-beta). Single crystal X-ray diffraction analyses show that I and II are isostructural and belong to the orthorhombic crystal system, space group P2(1)2(1)2(1) (No. 19). Compound I: a = 11.654 (1) Angstrom, b = 12.968(2) Angstrom, c = 16.273(2) Angstrom, Z= 4. Compound II: a b = 12.948(2) Angstrom, c = 16.285(1) Angstrom, Z = 4. The two polymorphs III-alpha and III-beta crystallize in the monoclinic system. Compound III-alpha: a = 11.815(2) Angstrom, b = 21.769(3) Angstrom, c = 14.498(4) Angstrom, beta = 95.43(2)degrees, Z = 4, space group P2(1)/c (No. 14). Compound III-beta: a = 22.154(3) Angstrom, b = 11.550(2) Angstrom, c = 14.230(2) Angstrom, beta = 99.05(1)degrees, Z = 4, space group P2(1)/a (No. 14). All four are Zintl compounds containing novel one-dimensional polymeric chains of (1)(infinity)[(In2Te6)(2-)] that can be described as alternating fused five-membered rings [(In3+)(2)(Te2(2-))(Te2-)], joined at the In atoms
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ARGUS laser plasma experiments at 1. 06. mu. m, 0. 53. mu. m and 0. 35. mu. m
No full textARGUS wavelength scaling experiments have been performed on low (Be) and high (Au) Z disk targets, with laser wavelengths of 1.06 ..mu..m, 0.53 ..mu..m and 0.35 ..mu..m. The laser provided a 700 psec pulse, with up to 100J and 1.06 ..mu..m; 200J at 0.53 ..mu..m; and 40J at 0.35 ..mu..m. Laser intensities on target ranged from 3 x 10/sup 13/ to over 3 x 10/sup 15/W/cm/sup 2/, using an f/2.2 focusing system. Box calorimeter measurements show the expected increasing fractional absorption at shorter laser wavelengths; absolutely calibrated hard x-ray detectors show the number of suprathermal electrons to be greatly decreased. Scattered light measurements concentrated on stimulated Raman scattering, and the 3/2 harmonic. The SRS was spectrally and temporally resolved during 0.53 ..mu..m irradiations; our measurements showed the scattering to be principally from the convective instability, near tenth critical density. Near ..omega../2, a double peaked spectral feature is observed. The time resolved data show a number of interesting features, which are discussed
Ubiquity and utility of --schemes
No full textLet , and be positive integers. A --{\it scheme of valency} and {\it order} is a array of subsets
such that for each row and column one has and , respectively. Any such scheme is an algebraic equivalent of a --semi--regular bipartite voltage
graph with and vertices in the bipartition sets and
voltages coming from the cyclic group . We are
interested in the subclass of --schemes that are
characterized by the property
(mod ) for all , , , and where and
need not be distinct. These
--schemes can be used to represent adjacency
matrices of regular graphs of girth and semi--regular
bipartite graphs of girth . For suitable with , they also represent
incidence matrices for polycyclic
configurations and, in particular, for all known Desarguesian
elliptic semiplanes. Partial projective closures yield {\it mixed
--schemes}, which allow new constructions for Kr\v
cadinac's sporadic configuration of type and Balbuena's
bipartite --regular graphs of girth on as few as
vertices, with ranging over prime powers.
Besides some new results, this survey essentially furnishes new
proofs in terms of (mixed) --schemes for ad--hoc
constructions used thus far
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