186,852 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
Search for decays at LHCb
No full textA search for decays is performed using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.1 . No evidence for signal is found. The 90 % confidence level upper limits are the first set for both decays and are K_{\textrm{S(L)}}^0\rightarrow\mu^{+}\mu^{-}\mu^{+}\mu^{-}fb^{-1}B(K_{\textrm{S}}^0\rightarrow\mu^{+}\mu^{-}\mu^{+}\mu^{-}) < 5.1\times 10^{-12}B(K_{\textrm{L}}^0\rightarrow\mu^{+}\mu^{-}\mu^{+}\mu^{-}) < 2.3\times 10^{-9}$
EXPTIME Tableaux for the Coalgebraic Mu-Calculus
No full textThe coalgebraic approach to modal logic provides a uniform framework that captures the semantics of a large class of structurally different modal logics, including e.g. graded and probabilistic modal logics and coalition logic. In this paper, we introduce the coalgebraic mu-calculus, an extension of the general (coalgebraic) framework with fixpoint operators. Our main results are completeness of the associated tableau calculus and EXPTIME decidability. Technically, this is achieved by reducing satisfiability to the existence of non-wellfounded tableaux, which is in turn equivalent to the existence of winning strategies in parity games. Our results are parametric in the underlying class of models and yield, as concrete applications, previously unknown complexity bounds for the probabilistic mu-calculus and for an extension of coalition logic with fixpoints
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
Two-Electron Redox Energetics in Ligand-Bridged Dinuclear Molybdenum and Tungsten Complexes
No full textElectron-transfer energetics of bridged dinuclear compounds of the form [(CO)(4)M(mu-L)](2)(0/1-/2-) (M = Mo, W; L = PPh(2)(-), SPh(-)) were explored using density functional theory coupled to a continuum solvation model. The experimentally observed redox potential inversion, a situation where the second of two electron transfers is more thermodynamically favorable than the first, was reproduced within this model. This nonclassical energy ordering is a prerequisite for the apparent transfer of two electrons at one potential, as observed in many biologically and technologically important systems. We pinpoint the origin of this phenomenon to be an unusually unfavorable electrostatic repulsion for the first electron transfer due to the redox noninnocent behavior of the bridging ligands. The extent of redox noninnocence is explained in terms of an orbital energy resonance between the metal-carbonyl and bridging ligand fragments, leading to a general mechanism by which potential inversion could be controlled in diamond-core dinuclear systems
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Improved upper limits on B(K{sub L}{sup 0} {r_arrow} {mu}e) and B(K{sub L}{sup 0} {r_arrow} ee) and a new value for B(K{sub L}{sup 0} {r_arrow} {mu}{mu})
No full textThe author gives recent results from E791 at BNL with improved upper limits on the branching fractions B(K{sub L}{sup 0} {r_arrow} {mu}e) and B(K{sub L}{sup 0} {r_arrow} ee) of 8.5 {times} 10{sup {minus}11} and 11.6 {times} 10{sup {minus}11} at 90% C.L. He also gives a preliminary result of a new measurement B(K{sub L}{sup 0} {r_arrow} {mu}{mu}) = 7.6 {+-} 0.5(stat) {+-} 0.4(syst) {times} 10{sup {minus}9}
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Transposable prophage Mu exists as an independent chromosomal domain in E. coli
No full texttextThe 4.6 Mb circular E. coli chromosome is compacted by segregation into 400-500 supercoiled domains, created by both active and passive mechanisms like transcription and DNA-binding proteins. We find that transposable prophage Mu, transcriptionally silent by definition, is organized into an independent domain as determined by the close proximity of Mu termini L and R separated by a 37 kb Mu genome. Cre-loxP recombination is used in this study in vivo and in vitro. Critical to formation/maintenance of the Mu 'domain' configuration are a strong gyrase site SGS at the center of Mu, the Mu L end, the MuB protein, and the E. coli nucleoid-associated proteins IHF, Fis and HU. The Mu domain was observed at two structurally different chromosomal locations, and was specific to the Mu prophage, i.e. was not observed for the [mathematical symbol] prophage. A model is proposed that by employing its cis-elements to create a domain barrier for segregation and compaction of its genome, the large selfish DNA element Mu profits from the transposition-ready arrangement of its ends, while simultaneously providing a fitness advantage to the host.Microbiolog
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Measurement of Br({Kappa}{sub L} {r_arrow} {mu}{sup +} {mu}{sup {minus}}): New results from BNL E791
No full textUsing a sample of 349 {Kappa}{sub L} {r_arrow} {mu}{sup +}{mu}{sup {minus}} candidates collected during the 1990 data run, the author measures a branching fraction Br({Kappa}{sub L} {r_arrow} {mu}{sup +}{mu}{sup {minus}}) = (6.96 {+-} 0.40 {+-} 0.22) {times} 10{sup {minus}9}. The sample used is the largest to date of {Kappa}{sub L} {r_arrow} {mu}{sup +}{mu}{sup {minus}} events. The result is close to the unitarity bound 6.83 {times} 10{sup {minus}9} coming from an absorptive 2-{gamma} intermediate state
UA1C11/105/42 Phi Mu Composite
No full textPhi Mu Sorority top row l to r: Juanita Smith, Anita Lawson, Barbara Barnes, Janie Cutrell, Candice Rice, Laura Lincoln, Marie Crews
2nd row l to r: Tabitha Aldridge, Kim Yates
3rd row l to r: Sasha Barny, Melony Jones
4th row l to r: Amy Wade, Becky Chambers, Patti Jeannette, Debra Kolemba, Ashley Smith, Kris Mills, Sheryl Brewe
UA1C11/105/41 Phi Mu Composite
No full textPhi Mu Sorority top row l to r: Melissa Pyles, Janie Cutrell, Debbie Abel, Laura Gibson, Susan Chamberlain, Melissa Addison, Gena Eberhard
2nd row l to r: Mary Wells, Christy Borthick
3rd row l to r: Angela Johnson, Tabitha Aldridge
4th row l to r: Leeann Monin, Theresa Donnermeyer, Marie Crews, Tim Hall, Kara Cantrell, Kimberly Yates, Juanita Smit
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