Above room temperature ferromagnetism in Si:Mn and TiO(2-delta)Co.

Science.gov (United States)

Granovsky, A; Orlov, A; Perov, N; Gan'shina, E; Semisalova, A; Balagurov, L; Kulemanov, I; Sapelkin, A; Rogalev, A; Smekhova, A

2012-09-01

We present recent experimental results on the structural, electrical, magnetic, and magneto-optical properties of Mn-implanted Si and Co-doped TiO(2-delta) magnetic oxides. Si wafers, both n- and p-type, with high and low resistivity, were used as the starting materials for implantation with Mn ions at the fluencies up to 5 x 10(16) cm(-2). The saturation magnetization was found to show the lack of any regular dependence on the Si conductivity type, type of impurity and the short post-implantation annealing. According to XMCD Mn impurity in Si does not bear any appreciable magnetic moment at room temperature. The obtained results indicate that above room temperature ferromagnetism in Mn-implanted Si originates not from Mn impurity but rather from structural defects in Si. The TiO(2-delta):Co thin films were deposited on LaAlO3 (001) substrates by magnetron sputtering in the argon-oxygen atmosphere at oxygen partial pressure of 2 x 10(-6)-2 x 10(-4) Torr. The obtained transverse Kerr effect spectra at the visible and XMCD spectra indicate on intrinsic room temperature ferromagnetism in TiO(2-delta):Co thin films at low (< 1%) volume fraction of Co.

Flame propagation enhancement by plasma excitation of oxygen. Part II: Effects of O{sub 2}(a{sup 1}{delta}{sub g})

Energy Technology Data Exchange (ETDEWEB)

Ombrello, Timothy; Won, Sang Hee; Ju, Yiguang [Department of Mechanical and Aerospace Engineering, Engineering Quadrangle, Olden Street, Princeton, NJ 08544 (United States); Williams, Skip [Air Force Research Laboratory, Propulsion Directorate, 1950 Fifth Street, Wright-Patterson AFB, OH 45433 (United States)

2010-10-15

The isolated effect of O{sub 2}(a{sup 1}{delta}{sub g}) on the propagation of C{sub 2}H{sub 4} lifted flames was studied at reduced pressures (3.61 kPa and 6.73 kPa). The O{sub 2}(a{sup 1}{delta}{sub g}) was produced in a microwave discharge plasma and was isolated from O and O{sub 3} by NO addition to the plasma afterglow in a flow residence time on the order of 1 s. The concentrations of O{sub 2}(a{sup 1}{delta}{sub g}) and O{sub 3} were measured quantitatively through absorption by sensitive off-axis integrated-cavity-output spectroscopy and one-pass line-of-sight absorption, respectively. Under these conditions, it was found that O{sub 2}(a{sup 1}{delta}{sub g}) enhanced the propagation speed of C{sub 2}H{sub 4} lifted flames. Comparison with the results of enhancement by O{sub 3} found in part I of this investigation provided an estimation of 2-3% of flame speed enhancement for 5500 ppm of O{sub 2}(a{sup 1}{delta}{sub g}) addition from the plasma. Numerical simulation results using the current kinetic model of O{sub 2}(a{sup 1}{delta}{sub g}) over-predicts the flame propagation enhancement found in the experiments. However, the inclusion of collisional quenching rate estimations of O{sub 2}(a{sup 1}{delta}{sub g}) by C{sub 2}H{sub 4} mitigated the over-prediction. The present isolated experimental results of the enhancement of a hydrocarbon fueled flame by O{sub 2}(a{sup 1}{delta}{sub g}), along with kinetic modeling results suggest that further studies of C{sub n}H{sub m} + O{sub 2}(a{sup 1}{delta}{sub g}) collisional and reactive quenching are required in order to correctly predict combustion enhancement by O{sub 2}(a{sup 1}{delta}{sub g}). The present experimental results will have a direct impact on the development of elementary reaction rates with O{sub 2}(a{sup 1}{delta}{sub g}) at flame conditions to establish detailed plasma-flame kinetic mechanisms. (author)

Effects of recharge and discharge on delta2H and delta18O composition and chloride concentration of high arsenic/fluoride groundwater from the Datong Basin, northern China.

Science.gov (United States)

Xie, Xianjun; Wang, Yanxin; Su, Chunli; Duan, Mengyu

2013-02-01

To better understand the effects of recharge and discharge on the hydrogeochemistry of high levels of arsenic (As) and fluoride (F) in groundwater, environmental isotopic composition (delta2H and delta18O) and chloride (Cl) concentrations were analyzed in 29 groundwater samples collected from the Datong Basin. High arsenic groundwater samples (As > 50 micog/L) were found to be enriched in lighter isotopic composition that ranged from -92 to -78 per thousand for deuterium (delta2H) and from -12.5 to -9.9 per thousand for oxygen-18 (delta18O). High F-containing groundwater (F > 1 mg/L) was relatively enriched in heavier isotopic composition and varied from -90 to -57 per thousand and from -12.2 to -6.7 per thousand for delta2H and delta18O, respectively. High chloride concentrations and delta18O values were primarily measured in groundwater samples from the northern and southwestern portions of the study area, indicating the effect of evaporation on groundwater. The observation of relatively homogenized and low delta18O values and chloride concentrations in groundwater samples from central part of the Datong Basin might be a result of fast recharge by irrigation returns, which suggests that irrigation using arsenic-contaminated groundwater affected the occurrence of high arsenic-containing groundwater in the basin.

A dynamic soil chamber system coupled with a tunable diode laser for online measurements of delta-13C, delta-18O, and efflux rate of soil respired CO2

Energy Technology Data Exchange (ETDEWEB)

Powers, Heath H [Los Alamos National Laboratory; Mcdowell, Nate [Los Alamos National Laboratory; Hanson, David [UNM; Hunt, John [LANDCARE RESEARCH

2009-01-01

High frequency observations of the stable isotopic composition of CO(2) effluxes from soil have been sparse due in part to measurement challenges. We have developed an open-system method that utilizes a flow-through chamber coupled to a tunable diode laser (TDL) to quantify the rate of soil CO(2) efflux and its delta(13)C and delta(18)O values (delta(13)C(R) and delta(18)O(R), respectively). We tested the method first in the laboratory using an artificial soil test column and then in a semi-arid woodland. We found that the CO(2) efflux rates of 1.2 to 7.3 micromol m(-2) s(-1) measured by the chamber-TDL system were similar to measurements made using the chamber and an infrared gas analyzer (IRGA) (R(2) = 0.99) and compared well with efflux rates generated from the soil test column (R(2) = 0.94). Measured delta(13)C and delta(18)O values of CO(2) efflux using the chamber-TDL system at 2 min intervals were not significantly different from source air values across all efflux rates after accounting for diffusive enrichment. Field measurements during drought demonstrated a strong dependency of CO(2) efflux and isotopic composition on soil water content. Addition of water to the soil beneath the chamber resulted in average changes of +6.9 micromol m(-2) s(-1), -5.0 per thousand, and -55.0 per thousand for soil CO(2) efflux, delta(13)C(R) and delta(18)O(R), respectively. All three variables initiated responses within 2 min of water addition, with peak responses observed within 10 min for isotopes and 20 min for efflux. The observed delta(18)O(R) was more enriched than predicted from temperature-dependent H(2)O-CO(2) equilibration theory, similar to other recent observations of delta(18)O(R) from dry soils (Wingate L, Seibt U, Maseyk K, Ogee J, Almeida P, Yakir D, Pereira JS, Mencuccini M. Global Change Biol. 2008; 14: 2178). The soil chamber coupled with the TDL was found to be an effective method for capturing soil CO(2) efflux and its stable isotope composition at high

Femosecond dynamics of quasi-particles in YBa sub 2 Cu sub 3 O sub 7 minus. delta. superconductor films

Energy Technology Data Exchange (ETDEWEB)

Han, S.G.; Vardeny, Z.V.; Symko, O.G. (Utah Univ., Salt Lake City, UT (United States). Dept. of Physics); Koren, G. (Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics)

1991-03-01

This paper reports on the transient electronic response of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} epitaxially grown HT{sub c} superconductor thin films in the femtosecond time domain, using transient photoinduced reflectivity ({Delta}R) with 60 fsec time resolution. For temperatures T {gt} T{sub c} only a bolometric signal was observed with {Delta}R {gt} O. For T {lt} T{sub c} {Delta}R {lt} O with a temperature dependent rise time of order 300 fsec followed by a relaxation (of order 3 psec) into a state with {Delta} are explained in terms of quasi-particle (QP) electronic response giving {Delta}R {lt} O. Thus the femtosecond rise time is interpreted as avalanche multiplication of QP across the gap 2{Delta} and the subsequent picosecond relaxation as QP recombination. The QP optical response is explained within the two fluid model.

On the calibration of continuous, high-precision delta18O and delta2H measurements using an off-axis integrated cavity output spectrometer.

Science.gov (United States)

Wang, Lixin; Caylor, Kelly K; Dragoni, Danilo

2009-02-01

The (18)O and (2)H of water vapor serve as powerful tracers of hydrological processes. The typical method for determining water vapor delta(18)O and delta(2)H involves cryogenic trapping and isotope ratio mass spectrometry. Even with recent technical advances, these methods cannot resolve vapor composition at high temporal resolutions. In recent years, a few groups have developed continuous laser absorption spectroscopy (LAS) approaches for measuring delta(18)O and delta(2)H which achieve accuracy levels similar to those of lab-based mass spectrometry methods. Unfortunately, most LAS systems need cryogenic cooling and constant calibration to a reference gas, and have substantial power requirements, making them unsuitable for long-term field deployment at remote field sites. A new method called Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) has been developed which requires extremely low-energy consumption and neither reference gas nor cryogenic cooling. In this report, we develop a relatively simple pumping system coupled to a dew point generator to calibrate an ICOS-based instrument (Los Gatos Research Water Vapor Isotope Analyzer (WVIA) DLT-100) under various pressures using liquid water with known isotopic signatures. Results show that the WVIA can be successfully calibrated using this customized system for different pressure settings, which ensure that this instrument can be combined with other gas-sampling systems. The precisions of this instrument and the associated calibration method can reach approximately 0.08 per thousand for delta(18)O and approximately 0.4 per thousand for delta(2)H. Compared with conventional mass spectrometry and other LAS-based methods, the OA-ICOS technique provides a promising alternative tool for continuous water vapor isotopic measurements in field deployments. Copyright 2009 John Wiley & Sons, Ltd.

Microwave plasma generation and filtered transport of O{sub 2} (a {sup 1}{delta}{sub g})

Energy Technology Data Exchange (ETDEWEB)

Williams, Skip [Air Force Research Laboratory, Mail Stop PRAS, 1950 Fifth Street, WPAFB, OH 45433-7251 (United States); Popovic, Svetozar [Department of Physics, Old Dominion University, Norfolk, VA 23529 (United States); Gupta, Manish [Los Gatos Research, Incorporated 67 East Evelyn Ave, Suite 3, Mountain View, CA 94041 (United States)], E-mail: skip.williams@wpafb.af.mil

2009-08-01

Singlet oxygen, O{sub 2}(a {sup 1}{delta}{sub g}), is generated using a low pressure, low power continuous microwave discharge operating at 2.45 GHz with a flow of helium seeded with 1-10% molecular oxygen. The absolute concentration of O{sub 2}(a {sup 1}{delta}{sub g}) is measured using off-axis integrated cavity output spectroscopy to probe the Q-branch transition of the (1, 0) band of the b{sup 1}{sigma}{sub g}{sup +}-a{sup 1}{delta}{sub g} Noxon system. In order to remove other energetic species from the flow, the post-discharge flow is passed through a coarse fritted quartz filter. The use of the quartz frit takes advantage of the substantially lower surface sticking probability of O{sub 2}(a {sup 1}{delta}{sub g}) in comparison with other excited species on the flow. Up to 6% of the total oxygen passing through the filter remains in the a {sup 1}{delta}{sub g} state, and absolute densities of 2.5 x 10{sup 14} cm{sup -3} are obtained using this method. This preparation method and transport is important in developing sources of singlet oxygen for kinetic and spectroscopic studies.

Ca substitution in RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (R = Y,Er; {delta}<0.15): the influence on the structure and the superconductivity

Energy Technology Data Exchange (ETDEWEB)

Boettger, G.; Fischer, P.; Mesot, J.; Furrer, A.; Zolliker, M.; Fauth, F. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Kaldis, E. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

1997-09-01

We present a combined neutron and X-ray diffraction study of the structural effects of Ca doping in RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (R = Y,Er; {delta}<0.15). Inelastic neutron scattering has been used to study the low-energy crystal-field (CEF) excitation of Er{sup 3+} in Er{sub 1-x}Ca{sub x}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} (0{<=}x{<=}0.2). (author) 1 figs., 4 refs.

Oxygen Nonstoichiometry and Defect Chemistry Modeling of Ce0.8Pr0.2O2-delta

OpenAIRE

Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

2010-01-01

The oxygen nonstoichiometry (delta) of Ce0.8Pr0.2O2−delta has been measured as a function of PO2 at temperatures between 600 and 900°C by coulometric titration and thermogravimetry. An ideal solution defect model, a regular solution model, and a defect association model, taking into account the association of reduced dopant species and oxygen vacancies, were unable to reproduce the experimental results. However, excellent agreement with the experimentally determined oxygen nonstoichiometry co...

Electronic Structure of TIBa(sub 2)CaCu(sub 2)O(sub 7-delta)

Science.gov (United States)

Vasquez, R. P.; Novikov, D. L.; Freeman, A. J.; Siegal, M. P.

1996-01-01

The core levels of TIBa(sub 2)CaCu(sub 2)O(sub 7-delta) epitaxial films have been measured with x-ray photoelectron spectroscopy (XPS). The valence electronic structure has been determined using the full-potential linear muffin tin orbital band structure method and measured with XPS.

Spatio-temporal distributions of delta¹⁸O, delta D and salinity in the Arabian Sea: Identifying processes and controls

Digital Repository Service at National Institute of Oceanography (India)

Deshpande, R.D; Muraleedharan, P.M.; Singh, R.L.; Kumar, B.; Rao, M.S.; Dave, M.; Sivakumar, K.U.; Gupta, S.K.

the geographic distributions of the delta^18O and S; (2) in spite of a large scatter, a statistically significant delta^18O–S relationship can be identified in much of the investigated part of the AS; (3) the delta^18O– delta...

Giant T{sub c} shift in HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}} and TlBa{sub 2}CaCu{sub 2}O{sub 7{minus}{delta}} superconductors due to Hg-Tl exchange

Energy Technology Data Exchange (ETDEWEB)

Gapud, A.A.; Wu, J.Z.; Kang, B.W.; Yan, S.L.; Xie, Y.Y. [Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045-2151 (United States); Siegal, M.P. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

1999-01-01

The irreversibility lines of epitaxial thin films of HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}} and TlBa{sub 2}CaCu{sub 2}O{sub 7{minus}{delta}}, whether deduced from field-induced magnetoresistive broadening or onset of nonhysteretic magnetization, were found to coincide when plotted against reduced temperature, showing the same exponential-decay temperature behavior for T/T{sub c}{lt}0.8 and power-law behavior for T/T{sub c}{gt}0.8 (where T{sub c} is zero-field, zero-resistivity critical temperature). These results indicate that replacing Tl with Hg has no noticeable effect on the anisotropy and suggests that T{sub c} is not determined by anisotropy. {copyright} {ital 1999} {ital The American Physical Society}

The growth hormone (GH) response to GH-releasing peptide (His-DTrp-Ala-Trp-DPhe-Lys-NH2), GH-releasing hormone, and thyrotropin-releasing hormone in acromegaly.

Science.gov (United States)

Alster, D K; Bowers, C Y; Jaffe, C A; Ho, P J; Barkan, A L

1993-09-01

In patients with acromegaly, GH-producing pituitary tumors release GH in response to specific stimuli such as GH-releasing hormone (GHRH) and are also responsive to a variety of nonspecific stimuli, such as TRH or GnRH, and may exhibit paradoxical responses to glucose and dopamine. In healthy humans, the synthetic peptide GH-releasing peptide (GHRP) (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2) releases GH by a putative mechanism of action that is independent of GHRH. How these tumors respond to GHRP is not well characterized. We studied the GH responses to GHRH, GHRP, and TRH stimulation in 11 patients with active acromegaly. The peak GH responses to GHRP and GHRH were not correlated (r = 0.57; P = 0.066). In contrast, the peak GH responses to GHRP and TRH were highly correlated (r = 0.95; P < 0.001). In conclusion, in patients with acromegaly, the GH response to GHRP is qualitatively normal and does not appear to depend on GHRH.

Reduction of free fatty acids by acipimox enhances the growth hormone (GH) responses to GH-releasing peptide 2 in elderly men

NARCIS (Netherlands)

Smid, HEC; de Vries, WR; Niesink, M; Bolscher, E; Waasdorp, EJ; Dieguez, C; Casanueva, FF; Koppeschaar, HPF

2000-01-01

GH release is increased by reducing circulating free fatty acids (FFAs). Aging is associated with decreased plasma GH concentrations. We evaluated GH releasing capacity in nine healthy elderly men after administration of GH-releasing peptide 2 (GHRP-2), with or without pretreatment with the

Houtman Abrolhos Isotope (delta 18O, delta 13C) Data for 1795 to 1994

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — DESCRIPTION: VARIABLES AND UNITS: Column #1: core depth in mm Column #2: delta C-13 vs V-PDB Column #3: delta O-18 vs V-PDB Column #4: assigned date in years A.D....

La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} ceramic powders prepared by combustion synthesis

Energy Technology Data Exchange (ETDEWEB)

Colomer, M.T.; Chinarro, E.; Jurado, J.R. [Consejo Nacional de Investigaciones Cientificas, Madrid (Spain). Ist. de Ceramica y Vidrio

2002-07-01

Combustion synthesis provides an attractive method of producing ceramic powders because of its low cost, process simplicity and fastness. Materials based on La{sub 2}NiO{sub 4+{delta}} can be successfully prepared by combustion synthesis. La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} (x = 0, 0.1) accommodates oxygen excess by oxygen interstitials rather than by the more usual cation vacancies. A high concentration of oxygen interstitials offers the possibility of rapid oxygen transport through the ceramic material and thus provide a new type of mixed ionic-electronic conductor. The fast oxide ion diffusion combined with its thermal stability indicate that these materials would be good candidates for use in ceramic oxygen generators (COGs) and intermediate temperature solid oxide fuel cells (IT-SOFCs). The present work discusses a combustion synthesis technique to prepare La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} (x = 0, 0.1) powders using the corresponding metal nitrates-urea mixtures, at low temperature and short reaction times. The as-prepared combustion powders were characterized by XRD, DTA-TG, SEM/TEM-EDX and BET. La{sub 2-x}Sr{sub x}NiO{sub 4} (x = 0, 0.1) powders with a good compositional control and homogeneity are attained. The as-prepared powders obtained at 300 C (ignition temperature) showed much higher specific surface area than powders obtained via alternative routes and contained La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}}, as the major phase present, together with La{sub 2}O{sub 3} and a small amount of NiO. La{sub 2-x}Sr{sub x}NiO{sub 4+{delta}} single phase is achieved, respectively at 950 C for x =0.1 and at 975 C for x = 0. (orig.)

Different growth hormone (GH) response to GH-releasing peptide and GH-releasing hormone in hyperthyroidism.

Science.gov (United States)

Ramos-Dias, J C; Pimentel-Filho, F; Reis, A F; Lengyel, A M

1996-04-01

Altered GH responses to several pharmacological stimuli, including GHRH, have been found in hyperthyroidism. The mechanisms underlying these disturbances have not been fully elucidated. GH-releasing peptide-6 (GHRP-6) is a synthetic hexapeptide that specifically stimulates GH release both in vitro and in vivo. The mechanism of action of GHRP-6 is unknown, but it probably acts by inhibiting the effects of somatostatin on GH release. The aim of this study was to evaluate the effects of GHRP-6 on GH secretion in patients with hyperthyroidism (n = 9) and in control subjects (n = 9). Each subject received GHRP-6 (1 microg/kg, iv), GHRH (100 microg, iv), and GHRP-6 plus GHRH on 3 separate days. GH peak values (mean +/- SE; micrograms per L) were significantly lower in hyperthyroid patients compared to those in control subjects after GHRH alone (9.0 +/- 1.3 vs. 27.0 +/- 5.2) and GHRP-6 plus GHRH (22.5 +/- 3.5 vs. 83.7 +/- 15.2); a lack of the normal synergistic effect of the association of both peptides was observed in thyrotoxicosis. However, a similar GH response was seen in both groups after isolated GHRP-6 injection (31.9 +/- 5.7 vs. 23.2 +/- 3.9). In summary, we have shown that hyperthyroid patients have a normal GH response to GHRP-6 together with a blunted GH responsiveness to GHRH. Our data suggest that thyroid hormones modulate GH release induced by these two peptides in a differential way.

Homogeneous samples of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}

Energy Technology Data Exchange (ETDEWEB)

Hoogenboom, B.W.; Kadowaki, K.; Revaz, B.; Fischer, O

2003-09-15

Recently, much attention has been paid to inhomogeneity in samples of the high-temperature superconductor Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}. In this work it is shown that homogeneous samples can indeed be obtained in the slightly overdoped range. However, the homogeneity critically depends on sample preparation.

Oxygen ordering in the high-T$_c$ superconductor HgBa$_2$CaCu$_2$O$_{6+\\delta}$ as revealed by perturbed angular correlation

CERN Document Server

Mendonca, Tania Melo; Haas, Heinz; Odier, Philippe; Tavares, Pedro; Silva, Manuel Ribeiro; Lopes, Armandina; Pereira, Andre; Goncalves, Joao Nuno; Amaral, Joao; Darie, Celine; Araujo, Joao Pedro

2011-01-01

Lattice sites and collective ordering of oxygen atoms in HgBa$_2$CaCu$_2$O$_{6+\\delta}$ were studied using the perturbed angular correlation (PAC) technique at ISOLDE/CERN. The electric field gradients (EFG) at $^{199m}$Hg nuclei have been measured as functions of oxygen doping on the Hg planes, above and below T$_c$. In comparison with the results obtained for oxygen and fluorine doping in Hg-1201, the analysis shows a different oxygen ordering exhibited by Hg-1212. Moreover, for all studied cases, the experimental results show that at a local scale there is non-uniform oxygen distribution. A series of ab initio EFG calculations allowed to infer that at low concentrations, regions without oxygen coexist with regions where O$_{2\\delta}$ dumbbell molecules are located at the center of the Hg mesh. On the other side, at high concentrations, O$_{2\\delta}$ dumbbell molecules coexist with single O$_\\delta$ atoms occupying the center of the Hg mesh. The present results suggest that oxygen sits on the Hg planes in t...

Human GH Receptor-IGF-1 Receptor Interaction: Implications for GH Signaling

Science.gov (United States)

Gan, Yujun; Buckels, Ashiya; Liu, Ying; Zhang, Yue; Paterson, Andrew J.; Jiang, Jing; Zinn, Kurt R.

2014-01-01

GH signaling yields multiple anabolic and metabolic effects. GH binds the transmembrane GH receptor (GHR) to activate the intracellular GHR-associated tyrosine kinase, Janus kinase 2 (JAK2), and downstream signals, including signal transducer and activator of transcription 5 (STAT5) activation and IGF-1 gene expression. Some GH effects are partly mediated by GH-induced IGF-1 via IGF-1 receptor (IGF-1R), a tyrosine kinase receptor. We previously demonstrated in non-human cells that GH causes formation of a GHR-JAK2-IGF-1R complex and that presence of IGF-1R (even without IGF-1 binding) augments proximal GH signaling. In this study, we use human LNCaP prostate cancer cells as a model system to further study the IGF-1R's role in GH signaling. GH promoted JAK2 and GHR tyrosine phosphorylation and STAT5 activation in LNCaP cells. By coimmunoprecipitation and a new split luciferase complementation assay, we find that GH augments GHR/IGF-1R complex formation, which is inhibited by a Fab of an antagonistic anti-GHR monoclonal antibody. Short hairpin RNA-mediated IGF-1R silencing in LNCaP cells reduced GH-induced GHR, JAK2, and STAT5 phosphorylation. Similarly, a soluble IGF-1R extracellular domain fragment (sol IGF-1R) interacts with GHR in response to GH and blunts GH signaling. Sol IGF-1R also markedly inhibits GH-induced IGF-1 gene expression in both LNCaP cells and mouse primary osteoblast cells. On the basis of these and other findings, we propose a model in which IGF-1R augments GH signaling by allowing a putative IGF-1R-associated molecule that regulates GH signaling to access the activated GHR/JAK2 complex and envision sol IGF-1R as a dominant-negative inhibitor of this IGF-1R-mediated augmentation. Physiological implications of this new model are discussed. PMID:25211187

Variation in leaf water delta D and delta 18O values during the evapotranspiration process

International Nuclear Information System (INIS)

Leopoldo, P.R.; Foloni, L.L.

1984-01-01

A theoretical model was developed to evaluate leaf water delta D and delta 18 O variation in relation to: leaf temperature, relative humidity converted to leaf temperature and delta D and delta 18 O values of atmospheric water vapour and soil water. (M.A.C.) [pt

Synthesis of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} whiskers and cross-whisker intrinsic Josephson junction

Energy Technology Data Exchange (ETDEWEB)

Hatano, T.; Takano, Y.; Arisawa, S.; Ishii, A.; Togano, K. [National Research Inst. for Metals, Tsukuba, Ibaraki (Japan); Fukuyo, A. [Science Univ. of Tokyo (Japan)

2001-03-01

A synthesis technique of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} single-crystal whiskers was studied. The whiskers were synthesized by heating glassy melt-quenched Bi-Sr-Ca-Cu-O (3:2:2:4 in cationic ratio) plates. The atmospheric condition of the whisker growth, especially oxygen partial pressure and gas flow, was investigated. It was found out that the whisker growth rate shows a maximum at P{sub O2}=2/3 bar. For the crystalline quality of the whiskers, the airtight condition was found to be useful as compared to the conventional oxygen stream condition. The crystalline quality, especially the straightness and morphology of the surface, could be improved by keeping the growing whiskers under the equilibrium P{sub Bi} condition. Over 20-mm-long whisker crystals have been successfully synthesized by choosing optimum oxygen partial pressure around the P{sub O2}=2/3 bar in the airtight condition. The growth condition and mechanism of the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} whiskers were investigated by an in-situ high-temperature x-ray diffraction analysis and an in-situ high-temperature microscope observation. It was found that the whiskers grow in a partially melted state at a temperature of 10-40 degrees below the melting point. The result obtained demonstrates that Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} whiskers grow at their bottom by the conventional liquid-phase growth mechanism, as was proposed by Matsubara et al. (author)

Synthesis, structural and physico-chemical studies of the monocrystal superconductor oxides Hg Ba{sub 2} Ca{sub n-1} Cu{sub n} O{sub 2n+2+{delta}}; Synthese, etudes structurales et physico-chimiques de monocristaux d`oxydes supraconducteurs Hg Ba{sub 2} Ca{sub n-1} Cu{sub n} O{sub 2n+2+{delta}}

Energy Technology Data Exchange (ETDEWEB)

Viallet-Guillen, Virginie [Dept. de Recherche sur l` Etat Condense, CEA Centre d` Etudes de Saclay, 91 - Gif-sur-Yvette (France)

1998-01-01

The thesis presents the synthesis and the structural and physico-chemical properties of the mercury-based monocrystal superconductor oxides. The results reported in the first chapter refer to the first three members of the mercury cuprate series Hg-1201, Hg-1212 and Hg-1223. In the second chapter detailed results concerning the structure of these compounds are given highlighting the features common to all cuprates and pointing out the peculiarities of mercury phases. The third chapter presents the phase diagrams ({delta}, T, p(O{sub 2})) of the compounds HgBa{sub 2}CuO{sub 4+{delta}} and HgBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+{delta}} obtained by thermogravimetry under controlled atmosphere between 150 deg.C and 500 deg.C and thermodynamic equilibrium conditions. In the case of Hg-1201, the critical temperature shows a variation close to a parabolic law, with an optimal Tc of 96 K ({delta}{approx_equal}0.10) while in Hg-1223 the Tc increases linearly with the O content up to the optimal Tc of 135 K ({delta}{approx_equal}0.19) and decreases only by 2 K in the over-doped regime. Finally, in the fourth chapter different physical properties are reviewed. The obtained monocrystals allowed studying the resistive transitory anisotropy, the torque, the specific heat, the nuclear magnetic resonance and the Raman diffusion 212 refs., 106 figs., 30 tabs.

The dynamics of central Main Ethiopian Rift waters: Evidence from {delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr ratios

Energy Technology Data Exchange (ETDEWEB)

Rango, Tewodros, E-mail: tewodros.godebo@duke.edu [Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)] [Addis Ababa University, Department of Earth Sciences, P.O. Box 1176, Addis Ababa (Ethiopia); Petrini, Riccardo; Stenni, Barbara [University of Trieste, Department of Geosciences, Via Weiss 1, I-34100 Trieste (Italy); Bianchini, Gianluca [Istituto di Geoscienze e Georisorse-CNR, Pisa (Italy)] [Department of Earth Sciences, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Slejko, Francesca [University of Trieste, Department of Geosciences, Via Weiss 1, I-34100 Trieste (Italy); Beccaluva, Luigi [Department of Earth Sciences, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Ayenew, Tenalem [Addis Ababa University, Department of Earth Sciences, P.O. Box 1176, Addis Ababa (Ethiopia)

2010-12-15

Research highlights: {yields} Chemical and isotope ({delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr) techniques are applied to understand various hydrological processes in the Main Ethiopian Rift. {yields} Some of the studied groundwaters display a depleted {delta}D-{delta}{sup 18}O composition when compared to the present-day average precipitation, thus suggesting that the rift floor aquifers also contains paleo-meteoric waters recharge associated with deep flow system. {yields} The pristine waters coming from the highlands display isotopic compositions characterized by less radiogenic {sup 87}Sr/{sup 86}Sr (and more depleted {delta}D, {delta}{sup 18}O). This isotopic signature subsequently evolves towards higher {sup 87}Sr/{sup 86}Sr by an interaction with the more radiogenic rhyolites of the rift and their weathered and redeposited products. - Abstract: Water samples from cold and geothermal boreholes, hot springs, lakes and rivers were analyzed for {delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr compositions in order to investigate lake water-groundwater mixing processes, water-rock interactions, and to evaluate groundwater flow paths in the central Main Ethiopian Rift (MER) of the Ziway-Shala basin. Different ranges of isotopic values were recorded for different water types: hot springs show {delta}{sup 18}O -3.36 to +3.69 and {delta}D -15.85 to +24.23, deep Aluto-Langano geothermal wells show {delta}{sup 18}O -4.65 to -1.24 and {delta}D -12.39 to -9.31, groundwater wells show {delta}{sup 18}O -3.99 to +5.14 and {delta}D -19.69 to +32.27, whereas the lakes show {delta}{sup 18}O and {delta}D in the range +3.98 to +7.92 and +26.19 to +45.71, respectively. The intersection of the Local Meteoric Water Line (LMWL: {delta}D = 7 {delta}{sup 18}O + 11.2, R{sup 2} = 0.94, n = 42) and the Local Evaporation Line (LEL: {delta}D = 5.63{delta}{sup 18}O + 8, n = 14, R{sup 2} = 0.82) was used to estimate the average isotopic composition of recharge water into the

Oxygen desorption from YBa2Cu3O(7-x) and Bi2CaSr2Cu2O(8 + delta) superconductors

Science.gov (United States)

Mesarwi, A.; Levenson, L. L.; Ignatiev, A.

1991-01-01

Oxygen desorption experiments from YBa2Cu3O(7-x) (YBCO) and Bi2CaSr2Cu2O(8 + delta) (BSCCO) superconductors were carried out using a quadrupole mass spectrometer for monitoring the desorbing species and X-ray photoemission spectroscopy for surface characterization. Molecular oxygen was found to desorb from both superconductors following photoirradiation with ultraviolet/optical radiation and subsequent heating at over 150 C. Both YBCO and BSCCO were found to have similar oxygen desorption rates and similar activation energies. The desorption data as well as the X-ray photoemission data indicate that the oxygen desorption is not intrinsic to the superconductors but rather due to molecular oxygen entrapped in the material.

Intermediate-to-low temperature protonic ceramic membrane fuel cells with Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}}-BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} composite cathode

Energy Technology Data Exchange (ETDEWEB)

Lin, Bin; Ding, Hanping; Dong, Yingchao; Wang, Songlin; Zhang, Xiaozhen; Fang, Daru; Meng, Guangyao [Department of Materials Science and Engineering, University of Science and Technology of China (USTC), Hefei, Anhui 230026 (China)

2009-01-01

The perovskite-type Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}}-BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BSCF-BZCY) composite oxides were synthesized by a modified Pechini method and examined as a novel composite cathode for intermediate-to-low temperature protonic ceramic membrane fuel cells (ILT-PCMFCs). Thin proton-conducting BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY) electrolyte and NiO-BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (NiO-BZCY) anode functional layer were prepared over porous anode substrates composed of NiO-BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} by a one-step dry-pressing/co-firing process. A laboratory-sized quad-layer cell of NiO-BZCY/NiO-BZCY({proportional_to}50 {mu}m)/BZCY({proportional_to}20 {mu}m)/BSCF-BZCY({proportional_to}50 {mu}m) was operated from 550 to 700 C with humidified hydrogen ({proportional_to}3% H{sub 2}O) as fuel and the static air as oxidant. A high open-circuit potential of 1.009 V, a maximum power density of 418 mW cm{sup -2}, and a low polarization resistance of the electrodes of 0.10 {omega} cm{sup 2} was achieved at 700 C. These investigations have indicated that proton-conducting BZCY electrolyte with BSCF perovskite cathode is a promising material system for the next generation solid oxide fuel cells (SOFCs). (author)

Growth hormone (GH) binding and effects of GH analogs in transgenic mice

Energy Technology Data Exchange (ETDEWEB)

Bartke, A.; Steger, R.W. [Southern Illinois Univ., Carbondale, IL (United States); Turyn, D. [UBA-CONICET, Buenos Aires (Argentina)] [and others

1994-12-31

Overexpression of human (h) or bovine (b) growth hormone (GH) in transgenic mice is associated with marked (2- to 12-fold) and significant increase in hepatic binding of GH and prolactin (PRL). This is due to an increase in the number of GH and PRL receptors (GHR, PRLR) per mg of microsomal protein without changes in binding affinity. Comparison of results obtained in transgenic animals expressing bGH with a mouse metallothionein (MT) or a rat phosphoenolpyruvate carboxykinase (PEPCK) promoter suggests that effects of bGH on hepatic GHR and PRLR do not require GH overexpression during fetal life and, within the dose range tested, the effects on PRLR are not dose dependent. The increase in hepatic GHR was accompanied by significant increases in plasma GH-binding protein (GHBP) and in mean residence time of injected GH. Thus life-long elevation of peripheral GH levels alters the availability of both free GH and GHR. Site-directed in vitro mutagenesis was used to produce hGH and bGH analogs mutated within one of the sites involved in binding to GHR and PRLR. Mutating hGH to produce amino acid identity with bGH at Position 11, 18 (within Helix 1), 57, or 60 (within the loop between Helix 1 and 2) did not affect binding to GHR in vitro, or somatotropic activity in transgenic mice in vivo but reduced lactogenic activity in Nb{sub 2} cells by 22%-45%. Mutations of bGH designed to produce amino acid identity with hGH at one to four of the corresponding positions in the bGH molecule did not interfere with binding to GHR or somatotropic activity in vivo, and failed to produce significant binding to PRLR but resulted in alterations in the effects on the hypothalamic and anterior pituitary function in transgenic mice. Apparently region(s) outside the domains examined are essential for lactogenic activity of hGH, and different portions of the GH molecule are responsible for its diverse actions in vivo. 35 refs.

Production and characterisation of glycoside hydrolases from GH3, GH5, GH10, GH11 and GH61 for chemo-enzymatic synthesis of xylo- and mannooligosaccharides

DEFF Research Database (Denmark)

Dilokpimol, Adiphol

Produktion og karakterisering af glykosid hydrolaser fro GH3, GH5, GH10, GH11 og GH61 til chemo-enzymatisk syntese af xylo- og mannooligosakkarider Biprodukter fra hydrolyse af plantecellevægge er kilder til oligosakkarider, som potentielt kan fungere som prebiotika ved at stimulere væksten af...... omfatter karakterisering af de producerede enzymer samt cDNA kloning af formodet GH61 endo Produktion og karakterisering af glykosid hydrolaser fro GH3, GH5, GH10, GH11 og GH61 til chemo-enzymatisk syntese af xylo- og mannooligosakkarider Biprodukter fra hydrolyse af plantecellevægge er kilder til...

Compatibilities of YBa2Cu3O(9-delta) type phase in quintenary systems Y-Ba-Cu-O-X (impurity)

Science.gov (United States)

Karen, P.; Braaten, O.; Fjellvag, H.; Kjekshus, A.

1991-01-01

Isothermal phase diagrams at various oxygen pressures were studied by powder diffraction and chemical analytical methods. The components, Y, Ba, Cu, and O (specifically O2, O2-, and O2 sup 2-) are treated, together with C (specifically CO2 and CO2 sup 2-), alkaline metals, Mg, alkaline earths, Sc, 3-d and 4-f elements. Effects of the substitutions at the structural sites of YBa2Cu3O(9-delta) on T sub c are discussed with respect to changes in crystallochemical characteristics of the substituted phase and to the nature of the substituents.

Compatibilities of YBa2Cu3O(9-delta)-type phase in quintenary systems Y-Ba-Cu-O-X (impurity)

International Nuclear Information System (INIS)

Karen, P.; Braaten, O.; Fjellvag, H.; Kjekshus, A.

1991-01-01

Isothermal phase diagrams at various oxygen pressures were studied by powder diffraction and chemical analytical methods. The components, Y, Ba, Cu, and O (specifically O2, O2-, and O2 sup 2-) are treated, together with C (specifically CO2 and CO2 sup 2-), alkaline metals, Mg, alkaline earths, Sc, 3-d and 4-f elements. Effects of the substitutions at the structural sites of YBa2Cu3O(9-delta) on T sub c are discussed with respect to changes in crystallochemical characteristics of the substituted phase and to the nature of the substituents

Chronic alcohol consumption, type 2 diabetes mellitus, insulin-like growth factor-I (IGF-I), and growth hormone (GH) in ethanol-treated diabetic rats.

Science.gov (United States)

Kim, Soo-Jeong; Ju, Anes; Lim, Seul-Gi; Kim, Dai-Jin

2013-11-13

Alcohol has deleterious influences on glucose metabolism which may contribute to the development of type 2 diabetes mellitus (T2DM). Insulin-like growth factor I (IGF-I) and growth hormone (GH), which interact with insulin to modulate metabolic control, have been shown to be related to impaired glucose tolerance. This study was conducted to assess the possibility that altered circulating IGF-I and GH levels contribute to the exacerbation of T2DM by alcohol use in type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats. OLETF rats were pair-fed a Lieber-DeCarli Regular Ethanol diet and LETO rats were pair-fed a control diet for 6 weeks. At 6 weeks, an Intraperitoneal Glucose Tolerance Test (IP-GTT) was performed and IGF-I and GH levels were evaluated. Prior to an IP-GTT, OLETF-Ethanol (O-E) group had significantly a decrease in the mean glucose levels compared to OLETF-Control (O-C) group. At 120 min post IP-GTT, the O-E group had significantly an increase in the mean glucose levels compared to O-C group. The serum IGF-I levels were significantly lower and the serum GH levels were significantly higher in the O-E group than in L-C group. These results suggest that IGF-I and GH are prominent in defining the risk and development of T2DM, and may be adversely affected by heavy alcohol use, possibly mediating its diabetogenic effects. Thus, the overall glucose intolerance in the setting of alcoholism may be attributable to inappropriate alteration of IGF-I and GH levels. © 2013. Published by Elsevier Inc. All rights reserved.

Inter-plane coupling in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}: impact of disorder and of magnetic field; Couplage interplan dans Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}: effet du desordre et du champ magnetique

Energy Technology Data Exchange (ETDEWEB)

Spathis, P

2006-07-01

The first part of this work is dedicated to the impact of structure disorder on the superconducting properties of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}. The quantity of disorder has been monitored through the irradiation with 2.5 MeV electrons. The Josephson plasma resonance has enabled us to study the impact of disorder on the inter-plan coupling. The second part is devoted to the properties of the mixed state of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}. When a magnetic field is applied transversely, it generates, for low inductions, a network of quantized flux lines called vortexes. The lamellar nature of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} implies that the vortexes generated are a piling up of low interacting magnetic dipoles. It is now well proved that inside the mixed phase, the solid vortex phase turns itself into a vortex liquid through a first order phase transformation. When the magnetic field is applied longitudinally to the CuO{sub 2} planes, a part of supra-currents are generated through Josephson effect. The consecutive vortexes are called Josephson vortexes and their cores are located between 2 superconducting planes. The first chapter recalls essential features of superconductivity and highlights the lamellar structure of cuprates. The second chapter describes the resonant cavity perturbation technique. The 2 last chapters deal respectively with the impact of energetic electron irradiation and with the impact of a slanting magnetic field on the phase coherence. (A.C.)

Phase compatibilities of YBa2Cu3O(9-delta) type structure in quintenary systems Y-Ba-Cu-O-X (impurity)

Science.gov (United States)

Karen, P.; Fjellvag, H.; Kjekshus, A.

1990-01-01

Electrical transport properties of the oxidic high T(sub c) superconductors are significantly affected by the presence of minor amounts of various elements adventing as impurities, e.g., from the chemical environment during manufacturing. YBa2Cu3O(9-delta) is prone to an extinction of the superconductivity on (partial) substitution of all four elemental components. E.g., Pr (for Y), La (for Ba), Zn (for Cu) or peroxygroup (for O) substituents will alter some of the superconductivity preconditions, like mixed valence state in Cu3O7/O(9-delta) network or structural distortion of the network. Although various pseudoternary chemical equilibrium phase diagrams of the Y(O)-Ba(O)-Cu(O) system now are available, no consensus is generally shown, however, this is partly due to lack of compatible definitions of the equilibrium conditions. Less information is available about the phase compatibilities in the appropriate quaternary phase diagram (including oxygen) and virtually no information exists about any pentenary phase diagrams (including one impurity). Unfortunately, complexity of such systems, stemming both from number of quaternary or pentenary compounds and from visualizing the five-component phase system, limits this presentation to more or less close surroundings of the YBa2Cu3O(9-delta) type phase in appropriate pseudoquaternary or pseudopseudoternary diagrams, involving Y-Ba-Cu and O, O-CO2, alkaline metals, Mg and alkaline earths, and Sc and most of the 3-d and 4-f elements. The systems were investigated by means of x ray diffraction, neutron diffraction and chemical analytical methods on samples prepared by sol-gel technique from citrates. The superconductivity was characterized by measuring the diamagnetic susceptibility by SQUID.

One-step synthesis of delta-MnO2 nanoparticles using ascorbic acid and their scavenging properties to Pb(II), Zn(II) and methylene blue

NARCIS (Netherlands)

Wang, M.X.; Pang, P.; Koopal, L.K.; Qiu, G.H.; Wang, Y.; Liu, F.

2014-01-01

To obtain delta-MnO2 particles with a large specific surface area, MnO2 was synthesized in an ice-water bath using ascorbic acid (AA) to reduce KMnO4. At pH 3 and 5 and KMnO4/AA molar ratios of 8/1 and 10/1, nanoparticles of delta-MnO2 were produced. The specific surface areas (SSAs) of the samples

Aerosol Observing System Greenhouse Gas (AOS GhG) Handbook

Energy Technology Data Exchange (ETDEWEB)

Biraud, S. C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Reichl, K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2016-03-01

The Greenhouse Gas (GhG) Measurement system is a combination of two systems in series: (1) the Tower Gas Processing (TGP) System, an instrument rack which pulls, pressurizes, and dries air streams from an atmospheric sampling tower through a series of control and monitoring components, and (2) the Picarro model G2301 cavity ringdown spectrometer (CRDS), which measures CO2, CH4, and H2O vapor; the primary measurements of the GhG system.

Formation of high-Tc YBa2Cu3O(7-delta) films on Y2BaCuO5 substrate

Science.gov (United States)

Wang, W. N.; Lu, H. B.; Lin, W. J.; Yao, P. C.; Hsu, H. E.

1988-07-01

High-Tc superconducting YBa2Cu3O(7-delta) films have been successfully prepared on green Y2BaCuO5 (2115) ceramic substrate. The films have been formed by RF sputtering and screen printing with post annealing at 925 C. Regarding superconducting features, the sharp resistivity drop with Tc onset around 95 K (midpoint 84 K) and 99 K (midpoint 89 K) has been observed for RF sputtered and printed films respectively. Both films show the excellent adhesion towards the 2115 substrate. Powder X-ray diffraction profiles indicate a majority of 1237 phase with preferred orientation for RF sputtered thin film.

Evidence of oxygen content heterogeneity in TSMTG YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}/Y{sub 2}BaCuO{sub 5} composites by micro-Raman spectrometry

Energy Technology Data Exchange (ETDEWEB)

Delorme, F. [Laboratoire CRISMAT, UMR CNRS 6508, ISMRA, Boulevard du Marechal Juin, 14050 Caen Cedex (France)], E-mail: f.delorme@brgm.fr; Bardeau, J.-F. [Laboratoire de Physique de l' Etat Condense, Faculte des Sciences, Universite du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 09 (France); Harnois, C. [Laboratoire CRISMAT, UMR CNRS 6508, ISMRA, Boulevard du Marechal Juin, 14050 Caen Cedex (France); Monot-Laffez, I. [Laboratoire LEMA, CNRS FRE-2077- CEA-LRC M01 - IUT de Blois, 3 Place Jean Jaures, CS2903, 41029 Blois (France)

2008-03-01

The homogeneity of the oxygen content of TSMTG-YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}/Y{sub 2}BaCuO{sub 5} composites has been investigated by micro-Raman spectrometry. The Y123 compound has been found to be very sensitive to the laser power, but a laser power of 0.04 mW has been shown to not to be harmful for the samples, even after 2 h of irradiation. Raman spectra have shown that the oxygen content of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}/Y{sub 2}BaCuO{sub 5} ceramics is not homogeneous at the micrometer scale. In addition, no monotonic decrease of the oxygen content is observed from the periphery to the core of the sample, confirming that the oxygen uptake is not strictly controlled by a diffusion process.

Estudo do comportamento cortisol, gh e insulina apos uma sessao de exercicio resistido agudo

Directory of Open Access Journals (Sweden)

Autran Jose Silva Jr.

2014-01-01

Full Text Available INTRODUÇÃO: Muitos trabalhos têm estudado o comportamento hormonal nos exercício resistido, entretanto poucos relacionam os hormônios cortisol, GH e insulina. OBJETIVO: Estudar os ajustes das concentrações plasmáticas dos hormônios cortisol, GH e insulina em exercícios resistidos de mesma intensidade com relação à massas musculares distintas. MÉTODOS: Dez voluntários, com 20,3 ± 4,2 anos, 74,1 ± 10,2 kg de peso, 177,2 ± 4,6 cm de estatura e 23,8 ± 3,2 kg/m2 de IMC, realizaram uma sessão de leg press (LP e supino reto (SR com quatro séries com 10 repetições a 70% 1 RM com três minutos de intervalo. Foram coletadas amostras de sangue para dosagem das concentrações plasmáticas de cortisol, GH e insulina em repouso (Pré e em 0' (Rec. 0', 30' (Rec. 30' e 90' (Rec. 90' de recuperação. RESULTADOS: As concentrações plasmáticas de cortisol foram significativamente reduzidas ao final da recuperação em LP (2,20±0,37 ng/dl para 1,33±0,38ng/dl em relação à pré-dosagem. As concentrações de GH e insulina elevaram-se significativamente durante a recuperação. GH em LP foi significativamente maior em Rec. 0' (2,75±3,29 ng/ml para 9,60±5,32 ng/dl do que em pré. A insulina elevou-se significativamente em Rec. 30' em LP (14,70±7,92 ulU/ml para 21,66 ± 8,61 ulU/ml e em SR (6,17 ± 2,99 ulU/ml para 19,70 ± 13,8 ulU/ml em relação à pré. As concentrações plasmáticas de insulina pré em LP foram significativamente superiores a SR (14,70 ulU/ml e 6,17 ± 2,99 ulU/ml. CONCLUSÃO: O exercício resistido promoveu diferentes ajustes nas concentrações hormonais de cortisol, GH e insulina durante o período de recuperação.

Impact of recombinant human growth hormone (rh-GH treatment on psychiatric, neuropsychological and clinical profiles of GH deficient adults: a placebo - controlled trial Impacto do tratamento com hormônio de crescimento recombinante (rh-GH sobre as características psiquiátricas, neuropsicológicas e clínicas de adultos com deficiência de GH: ensaio clínico duplo-cego controlado com placebo

Directory of Open Access Journals (Sweden)

CLÁUDIO DE NOVAES SOARES

1999-06-01

Full Text Available BACKGROUND: Untreated GH-deficient adults have a diversity of dysfunctions (e.g. reduced muscle strength, emotional instability during stress, depressive symptoms that may cause deleterious effects on quality of life, and may be positively influenced by recombinant human growth hormone (rh-GH therapy. AIM: To evaluate the impact of a clinical intervention with rh-GH therapy on GH - deficient adults. METHOD: The physical, psychiatric and neuropsychological status of 9 GH-deficient adults was determined before and after the administration of rh-GH (0.250 IU/Kg/week in a double blind placebo-controlled trial for six months. Patients then received rh-GH for a further period of 6 months and their status was re-evaluated. RESULTS: Rh-GH was significant better than placebo at 6th month (pINTRODUÇÃO: Pacientes com deficiência de hormônio de crescimento (GH apresentam diversas alterações clínicas (ex: redução de massa muscular e de função cardíaca e psíquicas (ex: quadros fóbicos, sintomas depressivos, déficits cognitivos. OBJETIVO: Avaliar o impacto da terapêutica com rh-GH em adultos com deficiência de GH. MÉTODO: Nove pacientes foram diagnosticados com deficiência de GH e então submetidos a ensaio clínico, duplo-cego, controlado, recebendo rh-GH (0,250UI/Kg/semana ou placebo, por período de 6 meses. RESULTADOS: Houve melhora significativa (p<0,05 em parâmetros clínicos ( aumento de massa muscular, redução do índice de massa corpórea (BMI, aumento de gasto energético, psiquiátricos (sintomas depressivos avaliados pelas escalas de Beck e Hamilton (p= 0,043 e neuropsicológicos (testes de atenção (p= 0,035, fluência verbal (FAS: p= 0,02, além da melhora de eficiência cognitiva (testes do WAIS-R: vocabulário (p= 0,027 , Arranjo de Figuras (p= 0,017, Compreensão (p= 0,01 . CONCLUSÃO: Prejuízos clínicos, psíquicos e neuropsicológicos causados pela deficiência de GH em adultos podem ser reduzidos pela terap

Effect of ageing on optical and thermal properties of YBa{sub 2}Cu{sub 3}O{sub 7}-{delta}

Energy Technology Data Exchange (ETDEWEB)

Nikolic, P.M.; Vujatovic, S.S.; Savic, S.M.; Ristic, M.M. [Institute of Technical Sciences of SASA, Belgrade (Czechoslovakia); Paraskevopoulos, K.M.; Zorbas, K.T. [Aristotle Univ., Thessaloniki (Greece). Solid State Section; Nikolic, M.V.; Aleksic, O.S. [Belgrade Univ. (Czechoslovakia). Center for Multidisciplinary Studies

2007-07-15

Photoacoustic phase and amplitude spectra of YBa{sub 2}Cu{sub 3}O{sub 7}-{delta} samples synthesised 18 years ago were measured and numerically analysed. The value of thermal diffusivity obtained on the aged samples was lower than the values obtained for fresh samples. Far infrared spectra of YBa{sub 2}Cu{sub 3}O{sub 7}-{delta} samples synthesised 18 years ago were recorded and analysed enabling determination of reflectivity peak phonon frequencies present at room temperature. X-ray diffraction analysis and far infrared reflectivity measurements enabled determination of a slight change of the oxygen content with time. The YBa{sub 2}Cu{sub 3}O{sub 7}-{delta} samples synthesised 18 years ago still remained superconducting, which was confirmed by resistivity measurements of the samples between 50 K and room temperature where the critical temperature was reduced from 93 to 73 K. Atomic force microscopy, scanning electron microscopy and energy dispersive X-ray microanalytical measurements were also performed confirming the composition of the sample. (orig.)

On the 590cm-1 B1g feature in underdoped Bi2Sr2CaCu2O8+delta

OpenAIRE

Hewitt, Kevin C.; Wang, N. L.; Irwin, J. C.; Pooke, D. M.; Pantoja, A. E.; Trodahl, H. J.

1999-01-01

Raman scattering studies have been performed on underdoped Bi2Sr2CaCu2O8+delta. In single crystals underdoped by oxygen removal, a 590 cm-1 peak is observed in the B1g spectrum. The feature is observed to soften in frequency by 3.8% with isotopic exchange for 16-O by 18-O. In contrast, the 590cm-1 peak is not observed in crystals underdoped by Y substitution which suggests that it correspond to a disorder induced vibrational mode. We have also found that underdoping leads to a depletion of lo...

Effect of cessation of GH treatment on cognition during transition phase in Prader-Willi syndrome: results of a 2-year crossover GH trial.

Science.gov (United States)

Kuppens, R J; Mahabier, E F; Bakker, N E; Siemensma, E P C; Donze, S H; Hokken-Koelega, A C S

2016-11-16

Patients with Prader-Willi syndrome (PWS) have a cognitive impairment. Growth hormone (GH) treatment during childhood improves cognitive functioning, while cognition deteriorates in GH-untreated children with PWS. Cessation of GH treatment at attainment of adult height (AH) might deteriorate their GH-induced improved cognition, while continuation might benefit them. We, therefore, investigated the effects of placebo versus GH administration on cognition in young adults with PWS who were GH-treated for many years during childhood and had attained AH. Two-year, randomized, double-blind, placebo-controlled cross-over study in 25 young adults with PWS. Cross-over intervention with placebo and GH (0.67 mg/m 2 /day), both during 1 year. Total (TIQ), verbal (VIQ) and performance IQ (PIQ) did not deteriorate during 1 year of placebo, compared to GH treatment (p > 0.322). Young adults with a lower TIQ had significantly more loss of TIQ points during placebo versus GH, in particular VIQ decreased more in those with a lower VIQ. The effect of placebo versus GH on TIQ, VIQ and PIQ was not different for gender or genotype. Compared to GH treatment, 1 year of placebo did not deteriorate cognitive functioning of GH-treated young adults with PWS who have attained AH. However, patients with a lower cognitive functioning had more loss in IQ points during placebo versus GH treatment. The reassuring finding that 1 year of placebo does not deteriorate cognitive functioning does, however, not exclude a gradual deterioration of cognitive functioning on the long term. ISRCTN24648386 , NTR1038 , Dutch Trial Register, www.trialregister.nl . Registered 16 August 2007.

Interactions of a La{sub O.9}Sr{sub O.1}Ga{sub O.8}Mg{sub O.2}O{sub 3-{delta}} electrolyte with Fe{sub 2}O{sub 3}, Co{sub 2}O{sub 3} and NiO anode materials

Energy Technology Data Exchange (ETDEWEB)

Zhang, X.; Ohara, S.; Okawa, H.; Maric, R.; Fukui, T. [Japan Fine Ceramics Center, 2-4-1 Mutsuo, Atsuta-ku, 456-8587 Nagoya (Japan)

2001-01-02

In this study, the interactions of a Sr- and Mg-doped lanthanum gallate (LSGM with composition La{sub O.9}Sr{sub O.1}Ga{sub O.8}Mg{sub O.2}O{sub 3-{delta}}) electrolyte with Fe{sub 2}O{sub 3}, Co{sub 2}O{sub 3} and NiO as the anode starting materials were investigated. It was found that the order of reactivity of the LSGM with the three oxides was Co{sub 2}O{sub 3}>NiO>Fe{sub 2}O{sub 3}, and La-containing oxides were detected in these binary powder mixtures after firing. The anode performance was greatly influenced by the interaction. The Fe{sub 2}O{sub 3}-LSGM anode, mixed with 40 vol.% LSGM powder and sintered at 1150C, exhibited the highest initial performance in comparison with NiO-LSGM and Co{sub 2}O{sub 3}-LSGM anodes. It seems that Fe{sub 2}O{sub 3} is a possible anode starting material for a LSGM-based solid oxide fuel cell.

High J{sub c} YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} Films via Rapid, Low pO{sub 2} Pyrolysis

Energy Technology Data Exchange (ETDEWEB)

DAWLEY,JEFFREY T.; CLEM,PAUL G.; SIEGAL,MICHAEL P.; OVERMYER,DONALD L.

2000-09-21

In this investigation, YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) films were fabricated via a metal acetate, trifluoroacetic acid based sol-gel route, and spin-coat deposited on (100) LaAlO{sub 3} with a focus on maximizing J{sub c}, while minimizing processing time. We demonstrate that the use of a low pO{sub 2} atmosphere during the pyrolysis stage can lead to at least a tetiold reduction in pyrolysis time, compared to a 1 atm. O{sub 2} ambient. High-quality YBCO films on LaAlO{sub 3}, with J{sub c} values up to 3 MA/cm{sup 2} at 77 K, can be routinely crystallized from these rapidly pyrolyzed films.

Microstructural investigation of RBa/sub 2/Cu/sub 3/O/sub 7-delta/ (R=Y, Gd, Nd)

Energy Technology Data Exchange (ETDEWEB)

Parent, L; Moreau, C; Noel, D; Dallaire, S; Champagne, B

1989-02-01

RBa/sub 2/Cu/sub 3/O/sub 7-delta/ perovskites, where R is Y, Gd and Nd, were synthesized using the same experimental conditions. The resistivity curves of the three compounds were similar but their microstructures were different. Secondary phases (CuO, BaCuO/sub 2/) were formed in the compounds containing Y and Gd while no such phases were detected in the Nd perovskite material. 7 refs.; 4 figs.; 1 table.

Effect of cessation of GH treatment on cognition during transition phase in Prader-Willi syndrome: results of a 2-year crossover GH trial

Directory of Open Access Journals (Sweden)

R. J. Kuppens

2016-11-01

Full Text Available Abstract Background Patients with Prader-Willi syndrome (PWS have a cognitive impairment. Growth hormone (GH treatment during childhood improves cognitive functioning, while cognition deteriorates in GH-untreated children with PWS. Cessation of GH treatment at attainment of adult height (AH might deteriorate their GH-induced improved cognition, while continuation might benefit them. We, therefore, investigated the effects of placebo versus GH administration on cognition in young adults with PWS who were GH-treated for many years during childhood and had attained AH. Method Two-year, randomized, double-blind, placebo-controlled cross-over study in 25 young adults with PWS. Cross-over intervention with placebo and GH (0.67 mg/m2/day, both during 1 year. Results Total (TIQ, verbal (VIQ and performance IQ (PIQ did not deteriorate during 1 year of placebo, compared to GH treatment (p > 0.322. Young adults with a lower TIQ had significantly more loss of TIQ points during placebo versus GH, in particular VIQ decreased more in those with a lower VIQ. The effect of placebo versus GH on TIQ, VIQ and PIQ was not different for gender or genotype. Conclusions Compared to GH treatment, 1 year of placebo did not deteriorate cognitive functioning of GH-treated young adults with PWS who have attained AH. However, patients with a lower cognitive functioning had more loss in IQ points during placebo versus GH treatment. The reassuring finding that 1 year of placebo does not deteriorate cognitive functioning does, however, not exclude a gradual deterioration of cognitive functioning on the long term. Trial registration ISRCTN24648386 , NTR1038 , Dutch Trial Register, www.trialregister.nl . Registered 16 August 2007.

Isotopic variations ({delta}{sup 13} C and {delta}{sup 18} O) in Siderastrea stellata (Cnidaria-Anthozoa), Itamaraca island, State of Pernambuco, Northeastern Brazil

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Valderez P.; Sial, Alcides N. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Geologia. Lab. de Isotopos Estaveis; Mayeal, Elga M.; Exner, Marco Antonio [Pernambuco Univ., Recife, PE (Brazil). Dept. de Zoologia. Lab. de Macro e Megabentos

1998-12-01

Isotopic determinations for O and C were performed in coral skeletons collected in beach rocks from two localities (Orange and Catuama), Itamaraca Island, north littoral of the State of pernambuco, northeastern Brazil. Large variations of {delta}{sup 18} O and {delta}{sup 13} C in corals from both localities are found, the largest ones being observed at the Orange locality {delta}{sup 13} C in this locality varies from -0.8 to +1.8% PDB and {delta}{sup 1.8} O from -5.3 to -1.8% PDB, while at the Catuama locality, they vary from -1.8 to 0.1% PDB and -3.8 to -2.7% PDB, respectively. Large variations in {delta}{sup 18} O (up to 2.5%) coupled with weakly defined positive correlation between {delta}{sup 18} O and {delta}{sup 13} C, can be attributed to temperature variations as consequence of climatic perturbations. Temperature estimates, calculated from {delta}{sup 18} O values, assuming isotopic equilibrium with seawater, yield values between 24.9 deg C and 43.1 deg C at Orange, and from 28.4 deg C to 35 deg C at Catuama, all of them (expect one growth band from one sample) are high enough for the full development of the coral colony. Temperature average is 31.4 deg C at Orange, which is a little bit higher than that at Catuama, but both of them indicate thermal stress conditions. In all analyzed specimens, expect for one, at Orange, T increases was accompanied by decreasing in the organic activity, as suggested by corresponding negative {delta}{sup 13} C anomaly. Therefore, the observed bleaching is possibly related to thermal stress and the high T may be related to the El Nino-Southern Oscillation (ENSO) warning event. On the other hand, anthropogenic action at Orange, local of intense tourism throughout the year, coupled with high rate of sedimentation in the region, may contribute to the observed coral bleaching. (author)

GH dysfunction in Engrailed-2 knockout mice, a model for autism spectrum disorders

Directory of Open Access Journals (Sweden)

Giovanni eProvenzano

2014-09-01

Full Text Available Insulin-like growth factor 1 (IGF-1 signaling promotes brain development and plasticity. Altered IGF-1 expression has been associated to autism spectrum disorders (ASD. IGF-1 levels were found increased in the blood and decreased in the cerebrospinal fluid of ASD children. Accordingly, IGF-1 treatment can rescue behavioral deficits in mouse models of ASD, and IGF-1 trials have been proposed for ASD children. IGF-1 is mainly synthesized in the liver, and its synthesis is dependent on growth hormone (GH produced in the pituitary gland. GH also modulates cognitive functions, and altered levels of GH have been detected in ASD patients.Here we analyzed the expression of GH, IGF-1, their receptors and regulatory hormones in the neuroendocrine system of adult male mice lacking the homeobox transcription factor Engrailed-2 (En2-/- mice. En2-/- mice display ASD-like behaviors (social interactions, defective spatial learning, increased seizure susceptibility accompanied by relevant neuropathological changes (loss of cerebellar and forebrain inhibitory neurons. Recent studies showed that En2 modulates IGF-1 activity during postnatal cerebellar development.We found that GH mRNA expression was markedly deregulated throughout the neuroendocrine axis in En2-/- mice, as compared to wild-type (WT controls. In mutant mice, GH mRNA levels were significantly increased in the pituitary gland, blood and liver, whereas decreased levels were detected in the hippocampus. These changes were paralleled by decreased levels of GH protein in the hippocampus but not other tissues of En2-/- mice. IGF-1 mRNA was significantly up-regulated in the liver and down-regulated in the En2-/- hippocampus, but no differences were detected in the levels of IGF-1 protein between the two genotypes. Our data strengthen the notion that altered GH levels in the hippocampus may be involved in learning disabilities associated to ASD.

Pair momentum distribution in Bi2Sr2CaCu2O(8+delta) measured by positron annihilation - Existence and nature of the Fermi surface

Science.gov (United States)

Chan, L. P.; Lynn, K. G.; Harshman, D. R.; Massidda, S.; Mitzi, D. B.

1991-09-01

The first measurement is reported of the position-electron momentum density in superconducting single-crystal Bi2Sr2CaCu2O(8+delta)(Tc roughly 90 K). The observed anisotropy exhibits a twofold (rather than fourfold) symmetry, which is attributed to the superlattice modulation along the b axis of the BiO2 layers. Subtraction of the superlattice contribution also reveals a pair momentum distribution consistent with the CuO2 and BiO2 Fermi surfaces, and in reasonable agreement with the theoretical pair momentum density derived from band theory.

Interface structure and electronic properties of SrTiO{sub 3} and YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} crystals and thin films

Energy Technology Data Exchange (ETDEWEB)

Thiess, S.

2007-07-01

Two new extensions of the X-ray standing wave (XSW) technique, made possible by the intense highly collimated X-ray beams from undulators at the ESRF, are described in this thesis. First, the XSW method was applied in a structural study to solve the nucleation mechanism of the high temperature superconductor YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} on the (001) surface of SrTiO{sub 3}. Second, the valence electronic structures of SrTiO{sub 3} and YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} were investigated. Finally, recent developments in the field of photoelectron spectroscopy in the hard X-ray region are described. The X-ray standing wave method is used in combination with fluorescence, Auger or photoelectron spectroscopy and lends very high spatial resolution power to these analytical techniques. Previously, the XSW method has been used for structure determination of surfaces and interfaces. The currently available X-ray intensities permit extensions to the XSW technique. Two recently established applications, described in this thesis, are XSW real space imaging and XSW valence electronic structure analysis. XSW real space imaging was employed to analyse the atomic structure of 0.5 and 1.0 layers of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} deposited on SrTiO{sub 3}(001). Three-dimensional images of the atomic distributions were reconstructed for each of the elements from experimentally determined Fourier components of the atomic distribution functions. The images confirmed the formation of a perovskite precursor phase prior to the formation of the YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} phase during the growth of the first monolayer of the film. XSW valence electronic structure analysis applied to SrTiO{sub 3} identified the valence band contributions arising from the strontium, titanium, and oxygen sites of the crystal lattice. Relations between the site-specific valence electronic structure and the lattice structure were established. The experimental results agree very well with

Critical parameters in the sputter-deposition of NdBa{sub 2}Cu{sub 3}O{sub 7-{delta}} thin films

Energy Technology Data Exchange (ETDEWEB)

Hakuraku, Y.; Yokoyama, N.; Doi, T.; Inoue, T. [Faculty of Engineering, Kagoshima University, Koorimoto, Kagoshima 890, (Japan); Mori, Z.; Koba, S. [Yatsushiro National College of Technology, Yatsushiro 866 (Japan)

1999-08-01

A superconducting thin film of NdBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (NBCO) was prepared on an MgO(100) substrate by dc magnetron sputtering. Superconducting properties as well as features such as resistivity at room temperature and surface morphology were improved by optimizing the composition of sputtering target and critical parameters such as substrate temperature and oxidation gas pressure. A highly c-axis oriented thin film with T{sub c} (zero resistance temperature) = 95.2 K was obtained reproducibly with NdBa{sub 2}Cu{sub 3.2}O{sub 7-{delta}} off-stoichiometric target sputtering. T{sub c} = 95.2 K was 8 K higher than that deposited by stoichiometric target sputtering. Critical current density was 1x10{sup 6} A cm{sup -2} at 77 K, and surface roughness was 35 nm. (author)

Delta 2.0

DEFF Research Database (Denmark)

Skott, Jeppe; Skott, Charlotte Krog; Jess, Kristine

DELTA 2.0 er en ny og helt opdateret udgave af Delta, der i ti år været brugt i matematiklærernes grund-, efter- og videreuddannelse. DELTA 2.0 er seriens almene fagdidaktik. Der er også fagdidaktiske overvejelser i de øvrige bøger i serien, men de er knyttet til specifikt matematisk indhold. DELTA...... 2.0 behandler mere generelle matematikdidaktiske problemstillinger såsom læringsteoretiske overvejelser i forbindelse med matematik, centrale aspekter af det at undervise i matematik og digitale teknologier som værktøj til at støtte elevers faglige læring af matematik....

Vitamin D across growth hormone (GH) disorders: From GH deficiency to GH excess.

Science.gov (United States)

Ciresi, A; Giordano, C

2017-04-01

The interplay between vitamin D and the growth hormone (GH)/insulin-like growth factor (IGF)-I system is very complex and to date it is not fully understood. GH directly regulates renal 1 alpha-hydroxylase activity, although the action of GH in modulating vitamin D metabolism may also be IGF-I mediated. On the other hand, vitamin D increases circulating IGF-I and the vitamin D deficiency should be normalized before measurement of IGF-I concentrations to obtain reliable and unbiased IGF-I values. Indeed, linear growth after treatment of nutritional vitamin D deficiency seems to be mediated through activation of the GH/IGF-I axis and it suggests an important role of vitamin D as a link between the proliferating cartilage cells of the growth plate and GH/IGF-I secretion. Vitamin D levels are commonly lower in patients with GH deficiency (GHD) than in controls, with a variable prevalence of insufficiency or deficiency, and this condition may worsen the already known cardiovascular and metabolic risk of GHD, although this finding is not common to all studies. In addition, data on the impact of GH treatment on vitamin D levels in GHD patients are quite conflicting. Conversely, in active acromegaly, a condition characterized by a chronic GH excess, both increased and decreased vitamin D levels have been highlighted, and the interplay between vitamin D and the GH/IGF-I axis becomes even more complicated when we consider the acromegaly treatment, both medical and surgical. The current review summarizes the available data on vitamin D in the main disorders of the GH/IGF-I axis, providing an overview of the current state of the art. Copyright © 2017 Elsevier Ltd. All rights reserved.

Initial isotopic geochemistry ({delta} 18 O, {delta} D) of fluids from wells of the Los Humeros, Pue., geothermal field; Geoquimica isotopica ({delta} 18 O, {delta} D) inicial de fluidos de pozos del campo geotermico de Los Humeros, Pue.

Energy Technology Data Exchange (ETDEWEB)

Barragan Reyes, Rosa Maria; Arellano Gomez, Victor Manuel [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)]. E-mail: rmb@iie.org.mx; Ramirez Montes, Miguel; Tovar Aguado, Rigoberto [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)

2010-01-15

Isotopic data ({delta} 18 O, {delta} D) from fluids from production wells at the Los Humeros, Pue., geothermal field were analyzed to investigate the possible origin of these fluids and the dominant processes of the reservoir at its initial state. According to pre-exploitation data, it is suggested the Los Humeros reservoir fluids are made of a mixture of meteoric water of very light isotopic composition (paleo-fluids) and andesitic water. The relationship {delta} D vs {delta} 18 O from pre-exploitation data indicates the produced fluids are composed of a mixture of (at least) two fluids with distinct isotopic compositions. At the more enriched end of the mixing relationship are the isotopic compositions of the wells H-23 and H-18 (located in the southern area of the field), while the lighter fluids were found in well H-16 (originally) and then in well H-16 (repaired). It was found that the liquid phases of deep wells are more enriched in {delta} 18 O while the shallow wells present lower values, suggesting a convection process at the initial state. Based on this isotopic profile, it is considered that even the production depths of the wells H-1, H-12 and H-16 (repaired) are just about the same, but their respective isotopic compositions are quite different. The {delta} 18 O value for well H-16 (repaired) seems to be that of condensate steam, while the corresponding values for wells H-1 and H-12 fall within the value interval of the deep wells (H-23). This suggests wells H-1 and H-12 are collecting very deep fluids enriched in {delta} 18 O. These results could be useful in creating a conceptual model of the reservoir. [Spanish] Se analizaron datos isotopicos ({delta}18 O, {delta}D) de los fluidos de pozos productores del campo geotermico de Los Humeros, Pue., para investigar el posible origen de los fluidos asi como los procesos dominantes del yacimiento en su estado inicial. De acuerdo con datos previos a la explotacion, se plantea que los fluidos del yacimiento

Annealing temperature and O2 partial pressure dependence of T(sub c) in HgBa2CuO(4+delta)

Science.gov (United States)

Xiong, Q.; Cao, Y.; Chen, F.; Xue, Y. Y.; Chu, C. W.

1994-01-01

Samples of HgBa2CuO(4+delta) (Hg-1201) were annealed under various conditions. After carefully controlling annealing time, annealing temperature (T(sub a)) and O2 partial pressure (P(sub 0)), we were able to find the reversible annealing conditions for Hg-1201. Under 1 atm O2 at 260 C less than or equal to T(sub a) less than or equal to 400 C, the obtained T(sub c) is nearly the same (approximately 97 K). However, it decreases quickly with T(sub a) greater than 300 C in high vacuum (P(sub 0) approximately 10(exp -8) atm), and reaches zero at T(sub a) = 400 C. On the other hand, T(sub c) decreases with the decrease of T(sub a) in high-pressure O2 (approximately 500 atm) and reaches approximately 20 K at about 240 C. In the entire annealing region, the oxygen surplus varies significantly from 0.03 to 0.4, and a wide range of T(sub c) variation (0 goes to 97 K goes to 20 K) was obtained with anion doping alone.

Secondary phase formation in YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} thin films and YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}/SrTiO{sub 3} superlattices

Energy Technology Data Exchange (ETDEWEB)

Johnson, C.N.L.

1996-06-01

Studies of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) thin films and YBCO/STO superlattices has been performed. The dc magnetron sputtered YBCO single layer investigation concerned the dependence of the secondary phase formation and superconducting transport properties on sputtering target and ambient gas composition. YBCO/STO superlattices, grown by dc and rf magnetron sputtering, respectively, were analyzed with respect to microstructure and formation of secondary phases. The main characterization techniques used in this study have been x-ray diffraction to identify phases and to obtain orientational relationships, scanning electron microscopy to study surface morphology, transmission electron microscopy for microstructural characterization, and energy-dispersive x-ray spectroscopy for chemical characterization. With the aim to reduce or avoid the formation of copper-rich surface particles and still maintain satisfactory superconducting transport properties, YBCO films were deposited using copper-poor or yttrium-rich sputtering targets in an Ar:O{sub 2} or Ar:O{sub 2}:N{sub 2}O sputtering gas mixture. It was found that the use of yttrium-rich targets and N{sub 2}O in the sputtering gas is a reliable way to achieve smooth films without surface particles and with satisfactory superconducting properties, while the use of copper-poor targets and N{sub 2}O deteriorates those properties. Based on the previous results, YBCO/STO superlattices were grown using yttrium-rich YBCO targets and stoichiometric STO targets, respectively, in a Ar:O{sub 2}:N{sub 2}O sputtering gas mixture. The superlattices were found to have sharp interfaces and no indications of interface reactions were detected. 61 refs, 18 figs, 3 tabs

Analysis of Domain Architecture and Phylogenetics of Family 2 Glycoside Hydrolases (GH2.

Directory of Open Access Journals (Sweden)

David Talens-Perales

Full Text Available In this work we report a detailed analysis of the topology and phylogenetics of family 2 glycoside hydrolases (GH2. We distinguish five topologies or domain architectures based on the presence and distribution of protein domains defined in Pfam and Interpro databases. All of them share a central TIM barrel (catalytic module with two β-sandwich domains (non-catalytic at the N-terminal end, but differ in the occurrence and nature of additional non-catalytic modules at the C-terminal region. Phylogenetic analysis was based on the sequence of the Pfam Glyco_hydro_2_C catalytic module present in most GH2 proteins. Our results led us to propose a model in which evolutionary diversity of GH2 enzymes is driven by the addition of different non-catalytic domains at the C-terminal region. This model accounts for the divergence of β-galactosidases from β-glucuronidases, the diversification of β-galactosidases with different transglycosylation specificities, and the emergence of bicistronic β-galactosidases. This study also allows the identification of groups of functionally uncharacterized protein sequences with potential biotechnological interest.

Critical current through grain boundary of metal oxide superconductors YBa sub 2 Cu sub 3 O sub 7-. delta. Kriticheskij tok cherez granitsu zeren metallooksidnykh sverkhprovodnikov YBa sub 2 Cu3O sub 7-. delta

Energy Technology Data Exchange (ETDEWEB)

Ermolov, S N; Kislov, N A; Marchenko, V A [and others

1989-06-01

Josephson junction with characteristics, corresponding to sandwich type structure is produced at 78 K at the link of large YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} crystallite with fine-grain structure. J{sub c}(H) dependence on the thermomagnetic prehistory is explained with regard to scattering fields of magnetic flux captured by grains.

Critical current density of strained multilayer thin films of Nd sub 1. 83 Ce sub 0. 17 CuO sub x /YBa sub 2 Cu sub 3 O sub 7 minus. delta

Energy Technology Data Exchange (ETDEWEB)

Gross, R.; Gupta, A.; Olsson, E.; Segmueller, A.; Koren, G. (IBM T. J. Watson Research Center, P.O. Box 218, Yorktown Heights, New York 10598 (USA))

1990-07-09

The superconducting transport properties of strained multilayer thin films of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}}/ Nd{sub 1.83}Ce{sub 0.17}CuO{sub {ital x}}, grown heteroepitaxially by laser ablation deposition, are reported. For individual layer thicknesses below a critical layer thickness of about 250 A, coherency strain removes the orthorhombic distortion in the YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} layers and makes them twin-free. Zero-field critical current densities as high as 1.1{times}10{sup 7} A/cm{sup 2} at 77 K have been measured for the YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} layers. Flux pinning energies at zero temperature and zero magnetic field in the range of 80--140 meV have been found.

Within-canopy and ozone fumigation effects on delta13C and Delta18O in adult beech (Fagus sylvatica) trees: relation to meteorological and gas exchange parameters.

Science.gov (United States)

Gessler, Arthur; Löw, Markus; Heerdt, Christian; de Beeck, Maarten Op; Schumacher, Johannes; Grams, Thorsten E E; Bahnweg, Günther; Ceulemans, Reinhart; Werner, Herbert; Matyssek, Rainer; Rennenberg, Heinz; Haberer, Kristine

2009-11-01

In this study, the effects of different light intensities either in direct sunlight or in the shade crown of adult beech (Fagus sylvatica L.) trees on delta13C and Delta18O were determined under ambient (1 x O3) and twice-ambient (2 x O3) atmospheric ozone concentrations during two consecutive years (2003 and 2004). We analysed the isotopic composition in leaf bulk, leaf cellulose, phloem and xylem material and related the results to (a) meteorological data (air temperature, T and relative humidity, RH), (b) leaf gas exchange measurements (stomatal conductance, g(s); transpiration rate, E; and maximum photosynthetic activity, A(max)) and (c) the outcome of a steady-state evaporative enrichment model. Delta13C was significantly lower in the shade than in the sun crown in all plant materials, whilst Delta18O was increased significantly in the shade than in the sun crown in bulk material and cellulose. Elevated ozone had no effect on delta13C, although Delta18O was influenced by ozone to varied degrees during single months. We observed significant seasonal changes for both parameters, especially in 2004, and also significant differences between the study years. Relating the findings to meteorological data and gas exchange parameters, we conclude that the differences in Delta18O between the sun and the shade crown were predominantly caused by the Péclet effect. This assumption was supported by the modelled Delta18O values for leaf cellulose. It was demonstrated that independent of RH, light-dependent reduction of stomatal conductance (and thus transpiration) and of A(max) can drive the pattern of Delta18O increase with the concomitant decrease of delta13C in the shade crown. The effect of doubling ozone levels on time-integrated stomatal conductance and transpiration as indicated by the combined analysis of Delta18O and delta13C was much lower than the influence caused by the light exposure.

Water and nitrogen conditions affect the relationships of Delta13C and Delta18O to gas exchange and growth in durum wheat.

Science.gov (United States)

Cabrera-Bosquet, Llorenç; Molero, Gemma; Nogués, Salvador; Araus, José Luis

2009-01-01

Whereas the effects of water and nitrogen (N) on plant Delta(13)C have been reported previously, these factors have scarcely been studied for Delta(18)O. Here the combined effect of different water and N regimes on Delta(13)C, Delta(18)O, gas exchange, water-use efficiency (WUE), and growth of four genotypes of durum wheat [Triticum turgidum L. ssp. durum (Desf.) Husn.] cultured in pots was studied. Water and N supply significantly increased plant growth. However, a reduction in water supply did not lead to a significant decrease in gas exchange parameters, and consequently Delta(13)C was only slightly modified by water input. Conversely, N fertilizer significantly decreased Delta(13)C. On the other hand, water supply decreased Delta(18)O values, whereas N did not affect this parameter. Delta(18)O variation was mainly determined by the amount of transpired water throughout plant growth (T(cum)), whereas Delta(13)C variation was explained in part by a combination of leaf N and stomatal conductance (g(s)). Even though the four genotypes showed significant differences in cumulative transpiration rates and biomass, this was not translated into significant differences in Delta(18)O(s). However, genotypic differences in Delta(13)C were observed. Moreover, approximately 80% of the variation in biomass across growing conditions and genotypes was explained by a combination of both isotopes, with Delta(18)O alone accounting for approximately 50%. This illustrates the usefulness of combining Delta(18)O and Delta(13)C in order to assess differences in plant growth and total transpiration, and also to provide a time-integrated record of the photosynthetic and evaporative performance of the plant during the course of crop growth.

Growth hormone (GH) secretion and pituitary size in children with short stature. Efficacy of GH therapy in GH-deficient children, depending on the pituitary size.

Science.gov (United States)

Hilczer, Maciej; Szalecki, Mieczysław; Smyczynska, Joanna; Stawerska, Renata; Kaniewska, Danuta; Lewinski, Andrzej

2005-10-01

Certain relationships between pituitary size and growth hormone (GH) secretion have previously been observed, however they are still a matter of controversy. Organic abnormalities of the hypothalamic-hypophyseal region are important for predicting growth response to GH therapy. Evaluation of relations between GH secretion and the pituitary size in short children and estimation of the efficacy of GH therapy in children with GH deficiency (GHD). The analysis comprised 216 short children (159 boys). Two GH stimulation tests, as well as magnetic resonance image (MRI) examination, were performed in each patient. All the patients with GHD were treated with GH for, at least, one year. Significant correlations were found between pituitary height and GH secretion (p < 0.05). Patients were classified into three (3) groups: 1) pituitary hypoplasia (HP) for height age; 2) HP for the chronological age but not for the height age; 3) normal pituitary size. Significant differences in GH secretion were observed among the groups (6.1+/-5.3 vs. 8.1+/-4.4 vs. 12.3+/-9.1 ng/mL, respectively). There was a negative correlation between GH peak and height gain during GH therapy (r = -0.34). The highest growth improvement was noticed in patients with HP for the height age. Pituitary hypoplasia for the height age is related to more severe GH deficiency and the best response to GH therapy.

Microstructure and hot corrosion behavior of the Ni-based superalloy GH202 treated by laser shock processing

Energy Technology Data Exchange (ETDEWEB)

Cao, Jiangdong [School of Material Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Mechanical and Electrical Department, Nantong Shipping College, Nantong, Jiangsu 226010 (China); Zhang, Junsong [School of Material Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Hua, Yinqun, E-mail: huayq@ujs.edu.cn [School of Material Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Chen, Ruifang [School of Mechanical Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Li, Zhibao [School of Material Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Ye, Yunxia [School of Mechanical Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China)

2017-03-15

The effects of laser shock processing on microstructure, the residual stress, and hot corrosion behavior of the Ni-based superalloy GH202 were investigated. The microstructures of GH202 before and after laser shock processing (LSP) were characterized by electron backscattered diffraction (EBSD) and transmission electron microscope (TEM). A large number of crystal defects (twins, dislocation arrays, and high dense tangles) were generated on the surface of GH202 treated with LSP. The cross-sectional compressive residual stress and micro-hardness of specimens treated by LSP were improved significantly. The corrosion kinetics of GH202 with or without LSP treatment at 800 °C and 900 °C were investigated. Analysis by X-ray diffraction (XRD) revealed that the corrosion products mainly consist of Cr{sub 2}O{sub 3}, TiO{sub 2}, Al{sub 2}O{sub 3}, NiO, CrS, Ni{sub 3}S{sub 2}, and Na{sub 2}CrO{sub 4}. The surface and cross-section morphologies were observed by scanning electron microscope (SEM) combined with energy dispersive spectroscopy (EDS). The results confirmed that the crystal defects induced by LSP promotes the creation of diffusion paths for elements (Cr, Al, and Ti), allowing the formation of tiny homogeneous oxidation films in a very short time. Additionally, the spallation of oxidation film on the treated specimens was alleviated significantly. Overall, the hot corrosion resistance of Ni-based GH202 induced by LSP was improved in Na{sub 2}SO{sub 4} and NaCl molten salt from 800 °C to 900 °C. - Highlights: • Microstructure changes of GH202 before and after LSP were observed by EBSD and TEM. • The hardness and residual compressive stress after LSP were significantly increased. • The increased diffusion paths for elements helped to form oxidation films quickly. • Hot corrosion resistance of GH202 after LSP was significantly improved.

Green Synthesis of Three-Dimensional MnO2/Graphene Hydrogel Composites as a High-Performance Electrode Material for Supercapacitors.

Science.gov (United States)

Meng, Xiaoyi; Lu, Liang; Sun, Chunwen

2018-05-16

Graphene hydrogels (GHs) and their composites have attracted wide attention because of the special structure of graphene assembly and exceptional electrochemical performance as electrodes for energy storage devices. Here, we report a GH with three-dimensional architecture prepared by a hydrothermal method via a self-assembled process in glucose and ammonia system as well as subsequent freeze-drying. The δ-MnO 2 /GH composite was then obtained by immersing GH in KMnO 4 solution with a certain concentration under heat treatment. The asymmetric supercapacitor MnO 2 /GH//GH consisting of pseudocapacitive nanosheet-like δ-MnO 2 /GH as the cathode and electric double-layer capacitive GH as the anode provides high energy density of 34.7 W h/kg at a power density of 1.0 kW/kg. Importantly, it is found that the pseudocapacitive behavior of MnO 2 has great effects on the rate performance of the supercapacitor, which is identified by kinetic analysis.

Circulating growth hormone (GH)-binding protein complex: a major constituent of plasma GH in man

International Nuclear Information System (INIS)

Baumann, G.; Amburn, K.; Shaw, M.A.

1988-01-01

The recent discovery of a specific binding protein for human GH (hGH) in human plasma suggests that hGH circulates in part as a complex in association with the binding protein(s). However, the magnitude of the complexed fraction prevailing under physiological conditions is unknown because of 1) dissociation of the complex during analysis and 2) potential differences in the binding characteristics of radiolabeled and native hGH. We conducted experiments designed to minimize dissociation during analysis (gel filtration in prelabeled columns, frontal analysis, and batch molecular sieving) with both native and radioiodinated hGH. All three methods yielded similar estimates for the complexed fraction. In normal plasma the bound fraction for 22 K hGH averaged 50.1% (range, 39-59%), that for 20 K hGH averaged 28.5% (range, 26-31%). Above a hGH level of about 20 ng/ml the bound fraction declines in concentration-dependent manner due to saturation of the binding protein. We conclude that a substantial part of circulating hGH is complexed with carrier proteins. This concept has important implications for the metabolism, distribution, and biological activity of hGH

Endothelial function and vascular oxidative stress in long-lived GH/IGF-deficient Ames dwarf mice.

Science.gov (United States)

Csiszar, Anna; Labinskyy, Nazar; Perez, Viviana; Recchia, Fabio A; Podlutsky, Andrej; Mukhopadhyay, Partha; Losonczy, Gyorgy; Pacher, Pal; Austad, Steven N; Bartke, Andrzej; Ungvari, Zoltan

2008-11-01

Hypopituitary Ames dwarf mice have low circulating growth hormone (GH)/IGF-I levels, and they have extended longevity and exhibit many symptoms of delayed aging. To elucidate the vascular consequences of Ames dwarfism we compared endothelial O2(-) and H2O2 production, mitochondrial reactive oxygen species (ROS) generation, expression of antioxidant enzymes, and nitric oxide (NO) production in aortas of Ames dwarf and wild-type control mice. In Ames dwarf aortas endothelial O2(-) and H2O2 production and ROS generation by mitochondria were enhanced compared with those in vessels of wild-type mice. In Ames dwarf aortas there was a less abundant expression of Mn-SOD, Cu,Zn-SOD, glutathione peroxidase (GPx)-1, and endothelial nitric oxide synthase (eNOS). NO production and acetylcholine-induced relaxation were also decreased in aortas of Ames dwarf mice. In cultured wild-type mouse aortas and in human coronary arterial endothelial cells treatment with GH and IGF significantly reduced cellular O2(-) and H2O2 production and ROS generation by mitochondria and upregulated expression of Mn-SOD, Cu,Zn-SOD, GPx-1, and eNOS. Thus GH and IGF-I promote antioxidant phenotypic changes in the endothelial cells, whereas Ames dwarfism leads to vascular oxidative stress.

New diagnostic tests of GH reserve.

Science.gov (United States)

Martul, P; Pineda, J; Pombo, M; Peñalva, A; Bokser, L; Dieguez, C

1993-01-01

Pharmacological tests are essential for the diagnosis of growth hormone (GH) insufficiency. Obesity is a pathological state associated with blunted GH response to all the classical stimuli tested. In the present study, three new pharmacological stimuli for GH reserve were evaluated in three groups of subjects: Normal, GH-insufficient and normal growing obese children. Dexamethasone provokes a clear GH-response in normal children, whereas the response in the other 2 groups of patients is significantly diminished. Galanin-induced GH-secretion is significantly higher in normal than in obese children. GHRP-6 causes a potent GH release in normal children, higher than in GH-insufficiency or obesity. The overlap shown between GH-insufficient patients and normal children reduces the usefulness of the tests. Similar to the classical stimuli, the response to these new tests is also decreased in obesity.

Microstructural investigation of RBa/sub 2/Cu/sub 3/O/sub 7/-delta (R=Y, Gd, Nd)

Energy Technology Data Exchange (ETDEWEB)

Parent, L; Moreau, C; Noel, D; Dallaire, S; Champagne, B

1989-01-01

RBa/sub 2/Cu/sub 3/O/sub 7-delta/ perovskites, where R is Y, Gd and Nd, were synthetized using the same experimental conditions. The resistivity curves of the three compounds were similar but their microstructures were different. Secondary phases (CuO, BaCuO/sub 2/) were formed in the compounds containing Y and Gd while no such phases were detected in the Nd perovskite material. According to these preliminary results, the perovskite containing Nd is readily synthesized since the amount of secondary phases is much lower in that case. 7 refs., 4 figs., 1 tab.

Increased linear bone growth by GH in the absence of SOCS2 is independent of IGF-1.

Science.gov (United States)

Dobie, Ross; Ahmed, Syed F; Staines, Katherine A; Pass, Chloe; Jasim, Seema; MacRae, Vicky E; Farquharson, Colin

2015-11-01

Growth hormone (GH) signaling is essential for postnatal linear bone growth, but the relative importance of GHs actions on the liver and/or growth plate cartilage remains unclear. The importance of liver derived insulin like-growth factor-1 (IGF-1) for endochondral growth has recently been challenged. Here, we investigate linear growth in Suppressor of Cytokine Signaling-2 (SOCS2) knockout mice, which have enhanced growth despite normal systemic GH/IGF-1 levels. Wild-type embryonic ex vivo metatarsals failed to exhibit increased linear growth in response to GH, but displayed increased Socs2 transcript levels (P growth over a 12 day period. Despite this increase, IGF-1 transcript and protein levels were not increased in response to GH. In accordance with these data, IGF-1 levels were unchanged in GH-challenged postnatal Socs2(-/-) conditioned medium despite metatarsals showing enhanced linear growth. Growth-plate Igf1 mRNA levels were not elevated in juvenile Socs2(-/-) mice. GH did however elevate IGF-binding protein 3 levels in conditioned medium from GH challenged metatarsals and this was more apparent in Socs2(-/-) metatarsals. GH did not enhance the growth of Socs2(-/-) metatarsals when the IGF receptor was inhibited, suggesting that IGF receptor mediated mechanisms are required. IGF-2 may be responsible as IGF-2 promoted metatarsal growth and Igf2 expression was elevated in Socs2(-/-) (but not WT) metatarsals in response to GH. These studies emphasise the critical importance of SOCS2 in regulating GHs ability to promote bone growth. Also, GH appears to act directly on the metatarsals of Socs2(-/-) mice, promoting growth via a mechanism that is independent of IGF-1. © 2014 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

Analysis of Surface Binding Sites (SBS) within GH62, GH13, and GH77

DEFF Research Database (Denmark)

Wilkens, Casper; Cockburn, Darrell; Andersen, Susan

2015-01-01

Certain interactions between carbohydrate active enzymes and polysaccharides involve surface binding sites (SBS) situated on catalytic domains outside of the active site. We recently undertook to develop a toolbox for SBS identification and characterization. In affinity gel electrophoresis (AGE...... of the reported SBSs. In GH13 SBSs have been seen in 17 subfamilies including SBSs with highly diverse functions in the same enzyme. Circumstantial evidence is provided for an SBS in the GH77 MalQ from Escherichia coli, the bacterial orthologue of Arabidopsis DPE2 involved in starch metabolism. Furthermore...

Electrical conductivity and oxygen exchange kinetics of La2NiO4+delta thin films grown by chemical vapor deposition

DEFF Research Database (Denmark)

Garcia, G.; Burriel, M.; Bonanos, Nikolaos

2008-01-01

Epitaxial c-axis oriented La2NiO4+delta films were deposited onto SrTiO3 and NdGaO3 substrates by the pulsed injection metal organic chemical vapor deposition technique. Experimental conditions were optimized in order to accurately control the composition, thickness, and texture of the layers. X......-ray diffraction was used to confirm the high crystalline quality of the obtained material. Electrical characterizations were performed on thin (50 nm) and thick (335 nm) layers. The total specific conductivity, which is predominantly electronic, was found to be larger for the thinner films measured (50 nm......), probably due to the effect of the strain present in the layers. Those thin films (50 nm) showed values even larger than those observed for single crystals and, to our knowledge, are the largest conductivity values reported to date for the La2NiO4+delta material. The oxygen exchange kinetics was studied...

(La{sub 0.74}Bi{sub 0.10}Sr{sub 0.16})MnO{sub 3-{delta}}-Ce{sub 0.8}Gd{sub 0.2}O{sub 2-{delta}} cathodes fabricated by ion-impregnating method for intermediate-temperature solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Li, Junliang; Wang, Shaorong; Wang, Zhenrong; Liu, Renzhu; Ye, Xiaofeng; Sun, Xiufu; Wen, Tinglian; Wen, Zhaoyin [Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China)

2009-03-15

Porous composite cathodes were fabricated by impregnating (La{sub 0.74}Bi{sub 0.10}Sr{sub 0.16})MnO{sub 3-{delta}} (LBSM) electronic conducting structure with the ionic conducting Ce{sub 0.8}Gd{sub 0.2}O{sub 2-{delta}} (GDC) phase. The ion impregnation of the GDC phase significantly enhanced the electrocatalytic activity of the LBSM electrodes for the O{sub 2} reduction reactions, and the ion-impregnated LBSM-GDC composite cathodes showed excellent performance. At 700 C, the value of the cathode polarization resistance (Rc) was only 0.097 {omega} cm{sup 2} for an ion-impregnated LBSM-GDC cathode, and the performance was gradually improved by increasing the loading of the impregnated GDC. For the performance testing of single cells, the maximum power density was 1036 mW cm{sup -2} at 700 C for a cell with the LBSM-GDC cathode. The results demonstrated the unique combination of the LBSM electronic conducting structure with high ionic conducting GDC phase was a valid method to improve the electrode performance, and the ion-impregnated LBSM-GDC was a promising composite cathode material for the intermediate-temperature solid oxide fuel cells. (author)

Structure and kinetic investigation of Streptococcus pyogenes family GH38 alpha-mannosidase.

Directory of Open Access Journals (Sweden)

Michael D L Suits

2010-02-01

Full Text Available The enzymatic hydrolysis of alpha-mannosides is catalyzed by glycoside hydrolases (GH, termed alpha-mannosidases. These enzymes are found in different GH sequence-based families. Considerable research has probed the role of higher eukaryotic "GH38" alpha-mannosides that play a key role in the modification and diversification of hybrid N-glycans; processes with strong cellular links to cancer and autoimmune disease. The most extensively studied of these enzymes is the Drosophila GH38 alpha-mannosidase II, which has been shown to be a retaining alpha-mannosidase that targets both alpha-1,3 and alpha-1,6 mannosyl linkages, an activity that enables the enzyme to process GlcNAc(Man(5(GlcNAc(2 hybrid N-glycans to GlcNAc(Man(3(GlcNAc(2. Far less well understood is the observation that many bacterial species, predominantly but not exclusively pathogens and symbionts, also possess putative GH38 alpha-mannosidases whose activity and specificity is unknown.Here we show that the Streptococcus pyogenes (M1 GAS SF370 GH38 enzyme (Spy1604; hereafter SpGH38 is an alpha-mannosidase with specificity for alpha-1,3 mannosidic linkages. The 3D X-ray structure of SpGH38, obtained in native form at 1.9 A resolution and in complex with the inhibitor swainsonine (K(i 18 microM at 2.6 A, reveals a canonical GH38 five-domain structure in which the catalytic "-1" subsite shows high similarity with the Drosophila enzyme, including the catalytic Zn(2+ ion. In contrast, the "leaving group" subsites of SpGH38 display considerable differences to the higher eukaryotic GH38s; features that contribute to their apparent specificity.Although the in vivo function of this streptococcal GH38 alpha-mannosidase remains unknown, it is shown to be an alpha-mannosidase active on N-glycans. SpGH38 lies on an operon that also contains the GH84 hexosaminidase (Spy1600 and an additional putative glycosidase. The activity of SpGH38, together with its genomic context, strongly hints at a function

Immune function during GH treatment in GH-deficient adults

DEFF Research Database (Denmark)

Sneppen, S B; Mersebach, H; Ullum, H

2002-01-01

investigated were unaltered. CONCLUSIONS: GH deficiency was associated with changes in lymphocyte subsets and impaired unstimulated and stimulated natural killer cell activity, but these remained abnormal during 18 months of GH replacement therapy. Extra-pituitary GH gene expression in, e.g. lymphoid tissues...

Evaluation of GdBaCo{sub 2}O{sub 5+{delta}} as cathode material for doped lanthanum gallate electrolyte IT-SOFCs

Energy Technology Data Exchange (ETDEWEB)

Tarancon, A. [Department of Inorganic Chemistry, University of La Laguna, La Laguna, Tenerife (Spain); EME/XaRMAE/IN, Department of Electronics, University of Barcelona (Spain); Marrero-Lopez, D.; Ruiz-Morales, J.C.; Nunez, P. [Department of Inorganic Chemistry, University of La Laguna, La Laguna, Tenerife (Spain); Pena-Martinez, J.

2008-10-15

The layered perovskite GdBaCo{sub 2}O{sub 5+{delta}} (GBCO), recently proposed for intermediate temperature solid oxide fuel cell applications, was investigated and compared with Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} (BSCF) cathode material using La{sub 0.9}A{sub 0.1}Ga{sub 0.8}Mg{sub 0.2}O{sub 2.85} (A=Sr,Ba) as electrolytes. Area-specific resistance was measured by impendance spectroscopy in symmetrical cells. The cobaltites were prepared by a modified citrate sol-gel route and tested as cathode materials for doped lanthanum gallate-based cells using dry H{sub 2} as fuel and air as oxidant, rendering power density values of 180 and 240 mW cm {sup -2} at 1,073 K (1 mm thick pellets) for GBCO and BSCF fuel cells, respectively. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

Supercurrents in HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}} and TlBa{sub 2}CaCu{sub 2}O{sub 7} epitaxial thin films

Energy Technology Data Exchange (ETDEWEB)

Gapud, A.A.; Wu, J.Z.; Fang, L.; Yan, S.L.; Xie, Y.Y. [Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045-2151 (United States); Siegal, M.P.; Overmyer, D.L. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

1999-06-01

The availability of high-quality epitaxial thin films of HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}} (Hg-1212) and TlBa{sub 2}CaCu{sub 2}O{sub 7} (Tl-1212) with high critical current densities (J{sub c}) has made it possible to examine and compare the J{sub c} of these species. Results reveal that the J{sub c} of 1212 species have very similar temperature behavior at low fields, strongly suggesting that the 30 K shift in critical temperature (T{sub c}) induced by the exchange of Hg and Tl in the 1212 structure is due largely to a change in charge carrier density and/or electronic band structure. {copyright} {ital 1999 American Institute of Physics.}

Ghrelin- and GH-induced insulin resistance

DEFF Research Database (Denmark)

Vestergaard, Esben Thyssen; Krag, Morten B; Poulsen, Morten M

2013-01-01

Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects.......Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects....

How yield relates to ash content, Delta 13C and Delta 18O in maize grown under different water regimes.

Science.gov (United States)

Cabrera-Bosquet, Llorenç; Sánchez, Ciro; Araus, José Luis

2009-11-01

Stable isotopes have proved a valuable phenotyping tool when breeding for yield potential and drought adaptation; however, the cost and technical skills involved in isotope analysis limit its large-scale application in breeding programmes. This is particularly so for Delta(18)O despite the potential relevance of this trait in C(4) crops. The accumulation of minerals (measured as ash content) has been proposed as an inexpensive way to evaluate drought adaptation and yield in C(3) cereals, but little is known of the usefulness of this measure in C(4) cereals such as maize (Zea mays). The present study investigates how yield relates to ash content, Delta(13)C and Delta(18)O, and evaluates the use of ash content as an alternative or complementary criterion to stable isotopes in assessing yield potential and drought resistance in maize. A set of tropical maize hybrids developed by CIMMYT were subjected to different water availabilities, in order to induce water stress during the reproductive stages under field conditions. Ash content and Delta(13)C were determined in leaves and kernels. In addition, Delta(18)O was measured in kernels. Water regime significantly affected yield, ash content and stable isotopes. The results revealed a close relationship between ash content in leaves and the traits informing about plant water status. Ash content in kernels appeared to reflect differences in sink-source balance. Genotypic variation in grain yield was mainly explained by the combination of ash content and Delta(18)O, whilst Delta(13)C did not explain a significant percentage of such variation. Ash content in leaves and kernels proved a useful alternative or complementary criterion to Delta(18)O in kernels for assessing yield performance in maize grown under drought conditions.

Synthesis, structural characterization and fluctuation conductivity of HoBa{sub 2}Cu{sub 3}O{sub 7-{delta}-}SrTiO{sub 3} composites

Energy Technology Data Exchange (ETDEWEB)

Uribe Laverde, M.A., E-mail: mauribel@bt.unal.edu.c [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, Bogota (Colombia); Landinez Tellez, D.A.; Roa-Rojas, J. [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, Bogota (Colombia)

2010-12-15

Single-phase polycrystalline samples of HoBa{sub 2}Cu{sub 3}O{sub 7-{delta}} superconductor and SrTiO{sub 3} isolator were produced by means of the solid state reaction technique. After structural characterization of both materials, superconductor-isolator composites were produced with nominal isolator volume percentages between 0% and 10%. Resistivity measurements for the composites and the HoBa{sub 2}Cu{sub 3}O{sub 7-{delta}} sample with different currents evidenced a superconducting transition with critical temperature T{sub C} = 92 K, with wider transitions with increasing either isolator content or measurement current. Fluctuation conductivity analyses were carried out to obtain the exponents characterizing the conductivity divergence. Above T{sub C}, apart from the typical Gaussian and critical fluctuations an atypical regime with critical exponent about 0.14 is observed as a precursor of the transition. Below T{sub C}, it is observed that the coherence transition characteristic exponent increases rapidly with increasing isolator percentage in the composites and does not show important changes when modifying the current in the pure superconductor sample.

Antiferromagnetic ordering in reduced Al doped YBa₂Cu_3-xAl_xO_6+#delta# single crystals

DEFF Research Database (Denmark)

Brecht, E.; Casalta, H.; Schleger, P.

1994-01-01

In YBa2Cu3-AlxO6+delta single crystals antiferromagnetic AFII ordering has been observed below 18 K by neutron diffraction. The transition temperature T-2 to the AFI ordering increases with x and delta.......In YBa2Cu3-AlxO6+delta single crystals antiferromagnetic AFII ordering has been observed below 18 K by neutron diffraction. The transition temperature T-2 to the AFI ordering increases with x and delta....

In situ screen-printed BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} electrolyte-based protonic ceramic membrane fuel cells with layered SmBaCo{sub 2}O{sub 5+x} cathode

Energy Technology Data Exchange (ETDEWEB)

Lin, Bin; Dong, Yingchao; Zhang, Shangquan; Hu, Mingjun; Zhou, Yang; Meng, Guangyao [Department of Materials Science and Engineering, University of Science and Technology of China (USTC), Hefei, Anhui 230026 (China); Yan, Ruiqiang [Department of Materials Engineering, Taizhou University, Linhai, Zhejiang 317000 (China)

2009-01-15

In order to develop a simple and cost-effective route to fabricate protonic ceramic membrane fuel cells (PCMFCs) with layered SmBaCo{sub 2}O{sub 5+x} (SBCO) cathode, a dense BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY) electrolyte was fabricated on a porous anode by in situ screen printing. The porous NiO-BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (NiO-BZCY) anode was directly prepared from metal oxide (NiO, BaCO{sub 3}, ZrO{sub 2}, CeO{sub 2} and Y{sub 2}O{sub 3}) by a simple gel-casting process. An ink of metal oxide (BaCO{sub 3}, ZrO{sub 2}, CeO{sub 2} and Y{sub 2}O{sub 3}) powders was then employed to deposit BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY) thin layer by an in situ reaction-sintering screen printing process on NiO-BZCY anode. The bi-layer with 25 {mu}m dense BZCY electrolyte was obtained by co-sintering at 1400 C for 5 h. With layered SBCO cathode synthesized by gel-casting on the bi-layer, single cells were assembled and tested with H{sub 2} as fuel and the static air as oxidant. A high open-circuit potential of 1.01 V, a maximum power density of 382 mW cm{sup -2}, and a low polarization resistance of the electrodes of 0.15 {omega} cm{sup 2} was achieved at 700 C. (author)

GH Responsiveness to Combined GH-Releasing Hormone and Arginine Administration in Obese Patients with Fibromyalgia Syndrome

Directory of Open Access Journals (Sweden)

Antonello E. Rigamonti

2017-01-01

Full Text Available Reportedly, fibromyalgia (FM is frequently associated with reduced IGF-1 levels and GH hyporesponsiveness to different GH stimulation tests. Since there is a high prevalence of obesity in FM, and obesity itself is characterized by hyposomatotropism, the aim of this study was to assess IGF-1 levels and GH responsiveness in sixteen severely obese women suffering from FM, who, subdivided into two subgroups on the basis of their age-dependent IGF-1 values (> or <−2 SDS, underwent the combined GHRH plus arginine test. Four out of 16 obese women with FM (25% had low IGF-1 SDS values, 2 cases of this subgroup (12.5% failing also to normally respond to the test. Among patients with normal GH responses, 4 showed a delayed GH peak. The subgroup with low IGF-1 SDS values had higher BMI than that with normal IGF-1 SDS. GH peak and area under the curve were not correlated with CRP, ESR, or tender point score, while significant correlations were found with fat-free mass and fat mass. In conclusion, this study shows the existence of a high prevalence of GH-IGF-1 dysfunction in patients with both FM and obesity, presumably as a consequence of the obese rather than fibromyalgic condition.

A comparative expression analysis of gene transcripts in brain tissue of non-transgenic and GH-transgenic zebrafish (Danio rerio using a DDRT-PCR approach

Directory of Open Access Journals (Sweden)

Fernanda A. Alves-Costa

2012-06-01

Full Text Available The presence of higher level of exogenous growth hormone (GH in transgenic animals could lead to several physiological alterations. A GH transgenic zebrafish (Danio rerio line was compared to nontransgenic (NT samples of the species through a DDRT-PCR approach, with the goal of identifying candidate differentially expressed transcripts in brain tissues that could be involved in GH overexpression. Densitometric analyses of two selected amplification products, p300 and ADCY2, pointed to a significant lower gene expression in the transgenic zebrafish (104.02 ± 57.71; 224.10 ± 91.73 when compared to NT samples (249.75 ± 30.08; 342.95 ± 65.19. The present data indicate that p300 and ADCY2 are involved in a regulation system for GH when high circulating levels of this hormone are found in zebrafishes.A presença de níveis mais elevados do hormônio de crescimento (GH em animais transgênicos poderia levar a várias alterações fisiológicas. Uma linhagem transgênica de paulistinha (Danio rerio para o GH foi comparada com amostras não transgênicas (NT desta espécie, através de uma abordagem de DDRT-PCR, com o objetivo de identificar transcritos candidatos diferencialmente expressos em tecido cerebral que poderiam estar envolvidos na superexpressão de GH. Análises densitométricas de dois produtos de amplificação selecionados, p300 e ADCY2, apontaram uma expressão gênica significativamente menor nas amostras transgênicas de paulistinha (104.02 ± 57.71; 224.10 ± 91.73, quando comparadas com as amostras NT (249.75 ± 30.08; 342.95±65.19. Os presentes dados indicam que p300 e ADCY2 estão envolvidos em um sistema de regulação do GH, quando altos níveis circulantes desse hormônio são encontrados em paulistinha.

RNA interference of GhPEPC2 enhanced seed oil accumulation and salt tolerance in Upland cotton.

Science.gov (United States)

Zhao, Yanpeng; Huang, Yi; Wang, Yumei; Cui, Yupeng; Liu, Zhengjie; Hua, Jinping

2018-06-01

Phosphoenolpyruvate carboxylase (PEPCase) mainly produces oxaloacetic acid for tricarboxylic acid (TCA) cycle. Here we reported that GhPEPC2 silencing with PEPC2-RNAi vector could regulate oil and protein accumulation in cottonseeds. In GhPEPC2 transgenic plants, PEPCase activities in immature embryos were significantly reduced, and the oil content in seed kernel was increased 7.3 percentages, whereas total proteins decreased 5.65 percentages. Compared to wild type, agronomical traits of transgenic plant were obviously unaffected. Furthermore, gene expression profile of GhPEPC2 transgenic seeds were investigated using RNA-seq, most lipid synthesis related genes were up-regulated, but amino acid metabolic related genes were down-regulated. In addition, the GhPEPC2 transgenic cotton seedlings were stressed using sodium salts at seedling stage, and the salt tolerance was significantly enhanced. Our observations of GhPEPC2 in cotton would shade light on understanding the regulation of oil content, protein accumulation and salt tolerance enhancement in other plants. Copyright © 2018 Elsevier B.V. All rights reserved.

Insulin and GH signaling in human skeletal muscle in vivo following exogenous GH exposure: impact of an oral glucose load.

Directory of Open Access Journals (Sweden)

Thomas Krusenstjerna-Hafstrøm

2011-05-01

Full Text Available GH induces acute insulin resistance in skeletal muscle in vivo, which in rodent models has been attributed to crosstalk between GH and insulin signaling pathways. Our objective was to characterize time course changes in signaling pathways for GH and insulin in human skeletal muscle in vivo following GH exposure in the presence and absence of an oral glucose load.Eight young men were studied in a single-blinded randomized crossover design on 3 occasions: 1 after an intravenous GH bolus 2 after an intravenous GH bolus plus an oral glucose load (OGTT, and 3 after intravenous saline plus OGTT. Muscle biopsies were taken at t = 0, 30, 60, and 120. Blood was sampled at frequent intervals for assessment of GH, insulin, glucose, and free fatty acids (FFA.GH increased AUC(glucose after an OGTT (p<0.05 without significant changes in serum insulin levels. GH induced phosphorylation of STAT5 independently of the OGTT. Conversely, the OGTT induced acute phosphorylation of the insulin signaling proteins Akt (ser(473 and thr(308, and AS160.The combination of OGTT and GH suppressed Akt activation, whereas the downstream expression of AS160 was amplified by GH. WE CONCLUDED THE FOLLOWING: 1 A physiological GH bolus activates STAT5 signaling pathways in skeletal muscle irrespective of ambient glucose and insulin levels 2 Insulin resistance induced by GH occurs without a distinct suppression of insulin signaling proteins 3 The accentuation of the glucose-stimulated activation of AS 160 by GH does however indicate a potential crosstalk between insulin and GH.ClinicalTrials.gov NCT00477997.

Puberty and Pubertal Growth in GH-treated SGA Children: Effects of 2 Years of GnRHa Versus No GnRHa.

Science.gov (United States)

van der Steen, Manouk; Lem, Annemieke J; van der Kaay, Danielle C M; Hokken-Koèelega, Anita C S

2016-05-01

Most studies on puberty in children born small for gestational age (SGA) report height and age at onset of puberty. GH-treated SGA children with an adult height (AH) expectation below -2.5 SDS at onset of puberty can benefit from an additional 2 years of GnRH analog (GnRHa) treatment. There are no data on puberty and growth after discontinuation of GnRHa treatment in GH-treated SGA children. This study aimed to investigate the effects on puberty and pubertal growth of 2 years GnRHa vs no GnRHa in GH-treated SGA children. This was a GH trial involving 76 prepubertal short SGA children (36 girls) treated with GH. Thirty-two children received additional GnRHa for 2 years. Pubertal stages were 3-monthly assessed according to Tanner. Age, bone age, and median height at pubertal onset were lower in girls and boys in the GH/GnRHa group compared with the GH group. In girls and boys treated with GH/GnRHa, pubertal duration after stop of GnRHa treatment was shorter than pubertal duration in those with GH only (40.9 vs 46.7 mo; P = .044; 50.8 vs 57.5 months; P = .006; respectively). Height gain from onset of puberty until AH, including height gain during 2 years of GnRHa treatment, was 25.4 cm in girls and 33.0 cm in boys, which was 6.6 cm more than girls and boys treated with GH only. AH was similar in children treated with GH/GnRHa compared with those with GH only. GH-treated SGA children who start puberty with an AH expectation below -2.5 SDS and are treated with 2 years of GnRHa have a shorter pubertal duration after discontinuation of GnRHa compared with pubertal duration in children treated with GH only. Height gain from onset of puberty until AH is, however, more due to adequate growth during 2 years of GnRHa treatment resulting in a similar AH as children treated with GH only.

Preparation and properties of Y{sub 1-x}Ho{sub x}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} thin films by TFA-MOD method

Energy Technology Data Exchange (ETDEWEB)

Jian Hongbin [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Li Qi; Shi Dongqi [Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong 2522 (Australia); Zhang Li [Department of Mathematic and Physics, Anhui University of Architecture, Hefei 230022 (China); Yang Zhaorong [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Dou Shixue [Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong 2522 (Australia); Zhu Xuebin, E-mail: xbzhu@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Sun Yuping [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

2011-12-15

Y{sub 1-x}Ho{sub x}BCO thin films were prepared by TFA-MOD. The best performances were obtained for the Y{sub 0.6}Ho{sub 0.4}BCO thin film. The pinning mechanism was {delta}l-type for all derived thin films. Y{sub 1-x}Ho{sub x}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) thin films were prepared on LaAlO{sub 3} (0 0 1) substrates by trifluoroacetate metal organic deposition (TFA-MOD) without change of the processing parameters. The highest J{sub c} was attributed to the sample of Y{sub 0.6}Ho{sub 0.4}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} thin film, whose critical current density is about 1.6 times as compared to that of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} thin film at 77 K and self field. The flux pinning type was not varied with Ho substitution and can be attributed to {delta}l pinning model, which is attributed to the close ionic radius between the Y{sup 3+} and Ho{sup 3+} ions. The improvement of J{sub c} by Ho substitution without change of the processing parameters will provide an effective route to enhance the J{sub c} of YBCO-based thin films using TFA-MOD method.

Abraham Reef Stable Isotope Data (delta 13C, delta 18O, delta 14C) for 1635-1957

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Site: Abraham Reef, 22ó 06'S, 153ó 00'E, Porites australiensus, Radiocarbon (delta 14C) and Stable Isotope (del 18O and del 13C) results from bi-annual samples from...

Immobilization of Glycoside Hydrolase Families GH1, GH13, and GH70: State of the Art and Perspectives

Directory of Open Access Journals (Sweden)

Natália G. Graebin

2016-08-01

Full Text Available Glycoside hydrolases (GH are enzymes capable to hydrolyze the glycosidic bond between two carbohydrates or even between a carbohydrate and a non-carbohydrate moiety. Because of the increasing interest for industrial applications of these enzymes, the immobilization of GH has become an important development in order to improve its activity, stability, as well as the possibility of its reuse in batch reactions and in continuous processes. In this review, we focus on the broad aspects of immobilization of enzymes from the specific GH families. A brief introduction on methods of enzyme immobilization is presented, discussing some advantages and drawbacks of this technology. We then review the state of the art of enzyme immobilization of families GH1, GH13, and GH70, with special attention on the enzymes β-glucosidase, α-amylase, cyclodextrin glycosyltransferase, and dextransucrase. In each case, the immobilization protocols are evaluated considering their positive and negative aspects. Finally, the perspectives on new immobilization methods are briefly presented.

Effect of cessation of GH treatment on cognition during transition phase in Prader-Willi syndrome: Results of a 2-year crossover GH trial

NARCIS (Netherlands)

R.J. Kuppens (Renske); Mahabier, E.F.; N.E. Bakker (Nienke); E.P.C. Siemensma (Elbrich); S.H. Donze (Stephanie); A.C.S. Hokken-Koelega (Anita)

2016-01-01

textabstractBackground: Patients with Prader-Willi syndrome (PWS) have a cognitive impairment. Growth hormone (GH) treatment during childhood improves cognitive functioning, while cognition deteriorates in GH-untreated children with PWS. Cessation of GH treatment at attainment of adult height (AH)

Electrical conductivity of cobalt doped La{sub 0.8}Sr{sub 0.2}Ga{sub 0.8}Mg{sub 0.2}O{sub 3-{delta}}

Energy Technology Data Exchange (ETDEWEB)

Wang, Shizhong; Wu, Lingli; Liang, Ying [Department of Chemistry, Xiamen University, Xiamen 361005, Fujian (China)

2007-03-30

La{sub 0.8}Sr{sub 0.2}Ga{sub 0.8}Mg{sub 0.2}O{sub 3-{delta}} (LSGM8282), La{sub 0.8}Sr{sub 0.2}Ga{sub 0.8}Mg{sub 0.15}Co{sub 0.05}O{sub 3-{delta}} (LSGMC5) and La{sub 0.8}Sr{sub 0.2}Ga{sub 0.8}Mg{sub 0.115}Co{sub 0.085}O{sub 3-{delta}} (LSGMC8.5) were prepared using a conventional solid-state reaction. Electrical conductivities and electronic conductivities of the samples were measured using four-probe impedance spectrometry, four-probe dc polarization and Hebb-Wagner polarization within the temperature range of 973-1173 K. The electrical conductivities in LSGMC5 and LSGMC8.5 increased with decreasing oxygen partial pressures especially in the high (>10{sup -5} atm) and low oxygen partial pressure regions (<10{sup -15} atm). However, the electrical conductivity in LSGM8282 had no dependency on the oxygen partial pressure. At temperatures higher than 1073 K, P{sub O{sub 2}} dependencies of the free electron conductivities in LSGM8282, LSGMC5 and LSGMC8.5 were about -1/4, and P{sub O{sub 2}} dependencies of the electron hole conductivities were about 0.25, 0.12 and 0.07, respectively. Oxygen ion conductivities in LSGMC5 and LSGMC8.5 increased with decreasing oxygen partial pressures especially in the high and low oxygen partial pressure regions, which was due to the increase in the concentration of oxygen vacancies. The change in the concentration of oxygen vacancies and the valence of cobalt with oxygen partial pressure were determined using a thermo-gravimetric technique. Both the electronic conductivity and oxygen ion conductivity in cobalt doped lanthanum gallate samples increased with increasing concentration of cobalt, suggesting that the concentration of cobalt should be optimized carefully to maintain a high electrical conductivity and close to 1 oxygen ion transference number. (author)

Adenomas produtores de GH: Análise de 20 casos

Directory of Open Access Journals (Sweden)

Tella Jr Oswaldo Inácio de

2002-01-01

Full Text Available Os adenomas produtores de GH podem ser mono, bi ou pluri-hormonais. A associação mais frequente do GH é com a sub unidade alfa ou com a prolactina. Apresentam-se com as alterações clássicas de acromegalia, mas quando produzem mais que um hormônio podem apresentar sintomas visuais. Os mono-hormonais são geralmente microadenomas e os outros dois grupos tendem a ser macroadenomas. Analisamos nossa experiência com 20 casos deste tipo de adenomas e mostramos o resultado cirúrgico, que foi bastante satisfatório para o grupo mono-hormonal. A radioterapia deve ser considerada quando a ressecção não foi total.

The origin of the superstructure in Bi2Sr2CaCu2O(8+delta) as revealed by scanning tunneling microscopy

Science.gov (United States)

Kirk, M. D.; Nogami, J.; Baski, A. A.; Mitzi, D. B.; Kapitulnik, A.

1988-12-01

Real-space images with atomic resolution of the BiO plane of Bi2Sr2CaCu2O(8+delta) were obtained with a scanning tunneling microscope. Single-crystal samples were cleaved and imaged under ultrahigh vacuum conditions at room temperature. The images clearly show the one-dimensional incommensurate superstructure along the b-axis that is common to this phase. High-resolution images show the position of the Bi atoms, revelaing the structural nature of the superlattice. A missing row of Bi atoms occurs either every nine or ten atomic sites in both 110-line directions, accounting for the measured incommensurate periodicity of the superstructure. A model is proposed that includes missing rows of atoms, as well as displacements of the atomic positions along both the a- and c-axis directions.

GH receptor signaling in skeletal muscle and adipose tissue in human subjects following exposure to an intravenous GH bolus

DEFF Research Database (Denmark)

Jørgensen, Jens O L; Jessen, Niels; Pedersen, Steen Bønløkke

2006-01-01

Growth hormone (GH) regulates muscle and fat metabolism, which impacts on body composition and insulin sensitivity, but the underlying GH signaling pathways have not been studied in vivo in humans. We investigated GH signaling in biopsies from muscle and abdominal fat obtained 30 (n = 3) or 60 (n...... was measured by in vitro phosphorylation of PI. STAT5 DNA binding activity was assessed with EMSA, and the expression of IGF-I and SOCS mRNA was measured by real-time RT-PCR. GH induced a 52% increase in circulating FFA levels with peak values after 155 min (P = 0.03). Tyrosine-phosphorylated STAT5...... tended to increase after GH in muscle and fat, respectively. We conclude that 1) STAT5 is acutely activated in human muscle and fat after a GH bolus, but additional downstream GH signaling was significant only in fat; 2) the direct GH effects in muscle need further characterization; and 3) this human...

The Colorado river delta (Mexico: ecological importance and management = O delta do rio Colorado (Mexico: importância ecológica e gerenciamento

Directory of Open Access Journals (Sweden)

José Luis Fermán Almada

2008-10-01

Full Text Available The Colorado river delta is a unique coastal system in the world, as it combines two important systems: the Colorado river and the Gulf of California. Consequently, the delta is dominated by bilateral interests, and influenced by administrative, political and natural processes, which involve the countries of the United States and Mexico. Located in the northern part of the Gulf of California, under a condition of natural isolation, a series of environmental attributeshave been developed (biotic and abiotic that are only observed in is region. In this work, the development of the bilateral political relations and the most important ecological characteristicsare presented, as well as the management instruments that have been developed for over 80 years. From these issues, the possible scenario for the region is defined, and the development of methodologies for monitoring the effects of these possible tendencies on the natural components of the delta is proposed.O delta do rio Colorado é uma zona costeira única em todo o mundo, porassociar dois importantes sistemas: o próprio rio Colorado e o Golfo da Califórnia. Conseqüentemente, o delta é dominado por interesses bi-nacionais e influenciado por processos administrativos, políticos e naturais, envolvendo os Estados Unidos e o México. Localizado no norte do Golfo da Califórnia, sob uma condição de isolamento natural,desenvolveu-se uma série de atributos ambientais (bióticos e abióticos que só podem ser vistos nessa região. Neste trabalho, são apresentados o desenvolvimento das relações políticas bilaterais e as características ecológicas mais importantes, bem como osmecanismos de gerenciamento que vêm sido desenvolvidos por mais de 80 anos. A partir dessas questões, é definido um cenário tendencial possível para a região, e o desenvolvimento de metodologias para o acompanhamento dos efeitos dessas possíveis tendências sobre os componentes naturais do delta é proposto.

Effects of methimazole treatment on growth hormone (GH) response to GH-releasing hormone in patients with hyperthyroidism.

Science.gov (United States)

Giustina, A; Ferrari, C; Bodini, C; Buffoli, M G; Legati, F; Schettino, M; Zuccato, F; Wehrenberg, W B

1990-12-01

In vitro studies have demonstrated that thyroid hormones can enhance basal and stimulated growth hormone secretion by cultured pituitary cells. However, both in man and in the rat the effects of high thyroid hormone levels on GH secretion are unclear. The aim of our study was to test the GH response to human GHRH in hyperthyroid patients and to evaluate the effects on GH secretion of short- and long-term pharmacological decrease of circulating thyroid hormones. We examined 10 hyperthyroid patients with recent diagnosis of Graves' disease. Twelve healthy volunteers served as controls. All subjects received a bolus iv injection of GHRH(1-29)NH2, 100 micrograms. Hyperthyroid patients underwent a GHRH test one and three months after starting antithyroid therapy with methimazole, 10 mg/day po. GH levels at 15, 30, 45, 60 min and GH peak after stimulus were significantly lower in hyperthyroid patients than in normal subjects. The GH peak was also delayed in hyperthyroid patients. After one month of methimazole therapy, most of the hyperthyroid patients had thyroid hormone levels in the normal range, but they did not show significant changes in GH levels after GHRH, and the GH peak was again delayed. After three months of therapy with methimazole, the hyperthyroid patients did not show a further significant decrease in serum thyroid hormone levels. However, mean GH levels from 15 to 60 min were significantly increased compared with the control study. The GH peak after GHRH was also earlier than in the pre-treatment study.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of dietary genistein on GH/IGF-I axis of Nile tilapia Oreochromis niloticus

Science.gov (United States)

Chen, Dong; Wang, Wei; Ru, Shaoguo

2016-09-01

There is considerable concern that isoflavones, such as genistein in fish feed composed of soybean protein, aff ects somatic growth in fish. Our previous works demonstrated that 30 and 300 μg/g dietary genistein had no significant eff ect on growth performance in Nile tilapia ( Oreochromis niloticus), but the higher level of genistein (3 000 μg/g) significantly depressed growth. This study was conducted to further examine the eff ects of dietary genistein on the endocrine disruption on growth hormone/insulin-like growth factor-I (GH/IGF-I) axis in Nile tilapia ( O. niloticus). Juvenile fish were fed by hand twice daily to satiation with one of four isonitrogenous and isoenergetic diets, each containing either 0, 30, 300 or 3 000 μg/g genistein. Following an 8-week feeding period, plasma GH and IGF-I levels were investigated by radioimmunoassay and gene expression levels of gh, ghrelin, gnrhs, ghr, npy, npyrs, pacap, ghrs, i gf-I, igf-Ir, and igfbp3 were examined by real-time PCR. The results show that no significant change in plasma GH and IGF-I levels in fish fed with diets containing 30 μg/g and 300 μg/g genistein. mRNA expression of genes along the GH/IGF-I axis remained unaff ected, except for igf-Ir, which was stimulated by the 300 μg/g genistein diet. While in fish fed the 3 000 μg/g genistein diet, the plasma GH and IGF-I levels decreased, and mRNA expression of gh, ghr2, npyr1, igf-I, and igf-Ir were also significantly depressed. In contrast, npy and igfbp3 mRNA expression were enhanced. This study provides convincing evidence for growth impediment by genistein by disturbing the GH/IGF-I axis in Nile tilapia O. niloticus.

PROPRIEDADES FARMACOCINÉTICAS E INTERAÇÃO DE HÍBRIDOS DE IBUPROFENO E PRODUTOS NATURAIS COM PROSTAGLANDINA G/H SINTASE 2

Directory of Open Access Journals (Sweden)

Adriano L. Romero

2014-12-01

Full Text Available Ibuprofen, in addition to having beneficial properties, cause serious side effects, ranging from gastrointestinal ulcerations until bleeding. These unwanted effects stimulate the research & development of new and more effective therapeutic agents and less harmful to human health. In this context, the aim of this study was to conduct an in silico study to evaluate pharmacokinetics properties, toxic effects and interaction of ibuprofenates derived from natural products with prostaglandin G/H synthase 2. The anisyl, thymil and eugenyl ibuprofenates showed molecular properties and low or no toxicity, expected for bioactive substances with potential drug candidates. Furthermore, it was observed that the ibuprofenates evaluated had higher interaction energy with the prostaglandin G/H synthase 2 in a similar orientation to ibuprofen drug.

Thermal properties of GdSr{sub 2}RuCu{sub 2}O{sub 8-{delta}} based mixtures in the GdSr{sub 2}RuO{sub 6}-CuO pseudo-binary system

Energy Technology Data Exchange (ETDEWEB)

Gombos, Marcello [Laboratorio Regionale Supermat CNR-INFM Via Salvador Allende, I-84081 Baronissi (Italy); Dipartimento di Fisica ' E.R.Caianiello' , Universita di Salerno, Via Salvador Allende, I-84081 Baronissi (Italy)], E-mail: gombos@sa.infn.it; Ciancio, Regina; Vecchione, Antonio; Pace, Sandro [Laboratorio Regionale Supermat CNR-INFM Via Salvador Allende, I-84081 Baronissi (Italy); Dipartimento di Fisica ' E.R.Caianiello' , Universita di Salerno, Via Salvador Allende, I-84081 Baronissi (Italy)

2007-09-01

GdSr{sub 2}RuCu{sub 2}O{sub 8-{delta}} (Gd1212) rutheno-cuprate compound is widely studied because it shows the coexistence of superconductivity and highly anisotropic magnetic ordering in the same cell. Anyway the nature of the magnetic ordering is still debated and the fabrication of macroscopic samples oriented along a crystallographic axis, that could help to clarify its details, appears to be quite difficult. For this reason, accurate investigation on Gd1212 incongruent melting reaction, producing liquid copper oxide and the solid GdSr{sub 2}RuO{sub 6} (Gd1210), appears to be necessary to improve the fabrication of crystallographically oriented bulk superconducting samples. Thermo-gravimetric and differential thermal measurements were performed to analyse the thermal behaviour up to 1200 deg. C and the melting temperatures of different mixtures of Gd1212 with Gd1210 or CuO, in view to perform a scan of the whole CuO-Gd1212-Gd1210 coexistence line of the Gd-Sr-Ru-Cu-O phase diagram. Dependence on the atmosphere and the formation of different spurious phases was also studied.

GhWRKY68 reduces resistance to salt and drought in transgenic Nicotiana benthamiana.

Directory of Open Access Journals (Sweden)

Haihong Jia

Full Text Available The WRKY transcription factors modulate numerous physiological processes, including plant growth, development and responses to various environmental stresses. Currently, our understanding of the functions of the majority of the WRKY family members and their possible roles in signalling crosstalk is limited. In particular, very few WRKYs have been identified and characterised from an economically important crop, cotton. In this study, we characterised a novel group IIc WRKY gene, GhWRKY68, which is induced by different abiotic stresses and multiple defence-related signalling molecules. The β-glucuronidase activity driven by the GhWRKY68 promoter was enhanced after exposure to drought, salt, abscisic acid (ABA and H2O2. The overexpression of GhWRKY68 in Nicotiana benthamiana reduced resistance to drought and salt and affected several physiological indices. GhWRKY68 may mediate salt and drought responses by modulating ABA content and enhancing the transcript levels of ABA-responsive genes. GhWRKY68-overexpressing plants exhibited reduced tolerance to oxidative stress after drought and salt stress treatments, which correlated with the accumulation of reactive oxygen species (ROS, reduced enzyme activities, elevated malondialdehyde (MDA content and altered ROS-related gene expression. These results indicate that GhWRKY68 is a transcription factor that responds to drought and salt stresses by regulating ABA signalling and modulating cellular ROS.

Inflammation and linear bone growth: the inhibitory role of SOCS2 on GH/IGF-1 signaling.

Science.gov (United States)

Farquharson, Colin; Ahmed, S Faisal

2013-04-01

Linear bone growth is widely recognized to be adversely affected in children with chronic kidney disease (CKD) and other chronic inflammatory disorders. The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) pathway is anabolic to the skeleton and inflammatory cytokines compromise bone growth through a number of different mechanisms, which include interference with the systemic as well as the tissue-level GH/IGF-1 axis. Despite attempts to promote growth and control disease, there are an increasing number of reports of the persistence of poor growth in a substantial proportion of patients receiving rhGH and/or drugs that block cytokine action. Thus, there is an urgent need to consider better and alternative forms of therapy that are directed specifically at the mechanism of the insult which leads to abnormal bone health. Suppressor of cytokine signaling 2 (SOCS2) expression is increased in inflammatory conditions including CKD, and is a recognized inhibitor of GH signaling. Therefore, in this review, we will focus on the premise that SOCS2 signaling represents a critical pathway in growth plate chondrocytes through which pro-inflammatory cytokines alter both GH/IGF-1 signaling and cellular function.

Therapeutic Efficacy and Safety of GH in Japanese Children with Down Syndrome Short Stature Accompanied by GH Deficiency.

Science.gov (United States)

Meguri, Kyoko; Inoue, Masaru; Narahara, Koji; Sato, Takahiro; Takata, Ami; Ohki, Nobuhiko; Ozono, Keiichi

2013-10-01

In this study, we investigated the effects of GH treatment in children with Down syndrome who had been diagnosed with GH deficiency (GHD). A total of 20 subjects were investigated in this study. Fourteen Down syndrome children (5 boys and 9 girls) with short stature due to GHD were treated with GH at Okayama Red Cross General Hospital, and 6 Down syndrome children (4 boys and 2 girls) with short stature due to GHD were registered in the Pfizer International Growth Database (KIGS). Height SD score (SDS) increased throughout the three-year GH treatment period. The overall mean height SDS increased from -3.5 at baseline to -2.5 after 3 yr of treatment. The mean change in height SDS during these 3 yr was 1.1. In addition, height assessment of SD score based on Down syndrome-specific growth data in the Japanese population revealed that the height SDS (Down syndrome) also increased across the 3-yr GH treatment period. The mean change in height SDS (Down syndrome) during these three years was 1.3. GH therapy was effective for Down syndrome short stature accompanied by GHD, and no new safety concerns were found in this study.

Liver-derived IGF-I contributes to GH-dependent increases in lean mass and bone mineral density in mice with comparable levels of circulating GH.

Science.gov (United States)

Nordstrom, Sarah M; Tran, Jennifer L; Sos, Brandon C; Wagner, Kay-Uwe; Weiss, Ethan J

2011-07-01

The relative contributions of circulating and locally produced IGF-I in growth remain controversial. The majority of circulating IGF-I is produced by the liver, and numerous mouse models have been developed to study the endocrine actions of IGF-I. A common drawback to these models is that the elimination of circulating IGF-I disrupts a negative feedback pathway, resulting in unregulated GH secretion. We generated a mouse with near total abrogation of circulating IGF-I by disrupting the GH signaling mediator, Janus kinase (JAK)2, in hepatocytes. We then crossed these mice, termed JAK2L, to GH-deficient little mice (Lit). Compound mutant (Lit-JAK2L) and control (Lit-Con) mice were treated with equal amounts of GH such that the only difference between the two groups was hepatic GH signaling. Both groups gained weight in response to GH but there was a reduction in the final weight of GH-treated Lit-JAK2L vs. Lit-Con mice. Similarly, lean mass increased in both groups, but there was a reduction in the final lean mass of Lit-JAK2L vs. Lit-Con mice. There was an equivalent increase in skeletal length in response to GH in Lit-Con and Lit-JAK2L mice. There was an increase in bone mineral density (BMD) in both groups, but Lit-JAK2L had lower BMD than Lit-Con mice. In addition, GH-mediated increases in spleen and kidney mass were absent in Lit-JAK2L mice. Taken together, hepatic GH-dependent production of IGF-I had a significant and nonredundant role in GH-mediated acquisition of lean mass, BMD, spleen mass, and kidney mass; however, skeletal length was dependent upon or compensated for by locally produced IGF-I.

Regulation of the growth hormone (GH) receptor and GH-binding protein mRNA

Energy Technology Data Exchange (ETDEWEB)

Kaji, Hidesuke; Ohashi, Shin-Ichirou; Abe, Hiromi; Chihara, Kazuo [Kobe Univ. School of Medicine, Kobe (Japan)

1994-12-31

In fasting rats, a transient increase in growth hormone-binding protein (GHBP) mRNA levels was observed after 1 day, in muscle, heart, and liver, but not in fat tissues. The liver GH receptor (GHR) mRNA level was significantly increased after 1 day (but not after 5 days) of bovine GH (bGH) treatment in fed rats. Both the liver GHR mRNA level and the net increment of plasma IGF-I markedly decreased after 5 days of bGH administration in fasting rats. These findings suggest that GHR and GHBP mRNAs in the liver are expressed in a different way and that the expression of GHBP mRNA is regulated differently between tissues, at least in rats. The results also suggest that refractoriness to GH in a sustained fasting state might be beneficial in preventing anabolic effects of GH. In humans, GHR mRNA in lymphocytes, from subjects with either GH-deficiency or acromegaly, could be detected by the reverse transcription-polymerase chain reaction method. In one patient with partial GH insensitivity, a heterozygous missense mutation (P561T) was identified in the cytoplasmic domain of GHR. 15 refs., 4 figs.

Crystallization and X-ray diffraction analysis of the CH domain of the cotton kinesin GhKCH2

Energy Technology Data Exchange (ETDEWEB)

Qin, Xinghua [China Agricultural University, No. 2 Yuanmingyuanxilu, Haidian District, Beijing 100094, People’s Republic of (China); The Fourth Military Medical University, No. 169 Changlexi Road, Xincheng District, Xi’an 710032, People’s Republic of (China); Chen, Ziwei; Li, Ping; Liu, Guoqin, E-mail: liu@cau.edu.cn [China Agricultural University, No. 2 Yuanmingyuanxilu, Haidian District, Beijing 100094, People’s Republic of (China)

2016-02-19

The cloning, expression, purification and crystallization of the CH domain of the plant-specific kinesin GhKCH2 is reported. GhKCH2 belongs to a group of plant-specific kinesins (KCHs) containing an actin-binding calponin homology (CH) domain in the N-terminus. Previous studies revealed that the GhKCH2 CH domain (GhKCH2-CH) had a higher affinity for F-actin (K{sub d} = 0.42 ± 0.02 µM) than most other CH-domain-containing proteins. To understand the underlying mechanism, prokaryotically expressed GhKCH2-CH (amino acids 30–166) was purified and crystallized. Crystals were grown by the sitting-drop vapour-diffusion method using 0.1 M Tris–HCl pH 7.0, 20%(w/v) PEG 8000 as a precipitant. The crystals diffracted to a resolution of 2.5 Å and belonged to space group P2{sub 1}, with unit-cell parameters a = 41.57, b = 81.92, c = 83.00 Å, α = 90.00, β = 97.31, γ = 90.00°. Four molecules were found in the asymmetric unit with a Matthews coefficient of 2.22 Å{sup 3} Da{sup −1}, corresponding to a solvent content of 44.8%.

Growth hormone (GH) and atherosclerosis: changes in morphology and function of major arteries during GH treatment.

Science.gov (United States)

Pfeifer, M; Verhovec, R; Zizek, B

1999-04-01

Patients with hypopituitarism have increased carotid artery intima-media thickness and reduced arterial distensibility. The effect of 2 years of growth hormone (GH) replacement therapy on these parameters was studied in 11 GH-deficient men (age range, 24-49 years) with hypopituitarism and compared with 12 healthy, age-matched men with no evidence of pituitary or vascular disease. Before treatment the intima-media of the common carotid arteries and the carotid bifurcations were significantly thicker in patients (P < 0.001) than in the control group. Treatment with GH normalized the intima-media thickness of the common carotid artery within 6 months and of the carotid bifurcation within 3 months. The changes in intima-media thickness of the carotid artery were negatively correlated with changes in serum levels of insulin-like growth factor I during treatment. There was a significant improvement in flow-mediated, endothelium-dependent dilation of the brachial artery at 3 months, which was sustained at 6, 18 and 24 months of GH treatment (P < 0.05). Thus, GH replacement therapy in GH-deficient men reverses early morphological and functional atherosclerotic changes in major arteries, and may reduce rates of vascular morbidity and mortality.

Carbon dynamics and CO2 and CH4 outgassing in the Mekong delta

Science.gov (United States)

Borges, Alberto V.; Abril, Gwenaël; Bouillon, Steven

2018-02-01

We report a data set of biogeochemical variables related to carbon cycling obtained in the three branches (Mỹ Tho, Hàm Luông, Cố Chiên) of the Mekong delta (Bến Tre province, Vietnam) in December 2003, April 2004, and October 2004. Both the inner estuary (upstream of the mouth) and the outer estuary (river plume) were sampled, as well as side channels. The values of the partial pressure of CO2 (pCO2) ranged between 232 and 4085 ppm, O2 saturation level (%O2) between 63 and 114 %, and CH4 between 2 and 2217 nmol L-1, within the ranges of values previously reported in temperate and tropical meso- and macro-tidal estuaries. Strong seasonal variations were observed. In the upper oligohaline estuary, low pCO2 (479-753 ppm) and high %O2 (98-106 %) values were observed in April 2004 most probably related to freshwater phytoplankton growth owing to low freshwater discharge (1400 m3 s-1) and increase in water residence time; during the two other sampling periods with a higher freshwater discharge (9300-17 900 m3 s-1), higher pCO2 (1895-2664 ppm) and lower %O2 (69-84 %) values were observed in the oligohaline part of the estuary. In October 2004, important phytoplankton growth occurred in the offshore part of the river plume as attested by changes in the contribution of particulate organic carbon (POC) to total suspended matter (TSM) (%POC) and the stable isotope composition of POC (δ13C-POC), possibly related to low TSM values (improvement of light conditions for phytoplankton development), leading to low pCO2 (232 ppm) and high %O2 (114 %) values. Water in the side channels in the Mekong delta was strongly impacted by inputs from the extensive shrimp farming ponds. The values of pCO2, CH4, %O2, and the stable isotope composition of dissolved inorganic carbon (δ13C-DIC) indicated intense organic matter degradation that was partly mediated by sulfate reduction in sediments, as revealed by the slope of total alkalinity (TA) and DIC covariations. The δ13C

GH and IGF1: Roles in Energy Metabolism of Long-Living GH Mutant Mice

OpenAIRE

Brown-Borg, Holly M.; Bartke, Andrzej

2012-01-01

Of the multiple theories to explain exceptional longevity, the most robust of these has centered on the reduction of three anabolic protein hormones, growth hormone (GH), insulin-like growth factor, and insulin. GH mutant mice live 50% longer and exhibit significant differences in several aspects of energy metabolism as compared with wild-type mice. Mitochondrial metabolism is upregulated in the absence of GH, whereas in GH transgenic mice and dwarf mice treated with GH, multiple aspects of t...

GH administration and discontinuation in healthy elderly men

DEFF Research Database (Denmark)

Lange, K H; Isaksson, F; Rasmussen, M H

2001-01-01

GH administration results in increased lean body mass (LBM), decreased fat mass (FM) and increased energy expenditure (EE). GH therapy may therefore have potential benefits, especially in the elderly, who are known to have decreased function of the GH/IGF-I axis. Several studies have focused...... discontinuation on body composition, resting oxygen uptake (VO2), resting heart rate (HR) and GH related serum markers in healthy elderly men....

The role of Ca substitution on the nature of the superconducting transition of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}

Energy Technology Data Exchange (ETDEWEB)

Jaeckel, S.T.; Lopes, L.F.; Nunes, S.E.; Mendonca, A.P.A.; Lopes, R.F.; Vieira, V.N. [Universidade Federal de Pelotas, RS (Brazil). Inst. de Fisica e Matematica; Pureur, P.; Pimentel Junior, J.L.; Rosa, F.M. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Inst. de Fisica; Ferreira, L.M. [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas

2012-07-01

Full text: In this work we report the results of an experimental study about the superconducting transition of Ca- doped YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}samples. Temperature dependent in-plane resistivity measurements were carried out on Y{sub 1-x}Ca{sub x}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} single crystals with Ca content x = 0, 0.01, 0.05, 0.10. The samples were studied under hydrostatic pressure conditions (P {<=}15 kbar) and applied magnetic fields (H {<=} 2500 Oe) with H parallel to the c-axis. From the analysis of the contribution of superconducting fluctuations to the electrical conductivity we identified a fluctuation regime described by the small exponent {lambda}{sub cr} = 0.20 in a narrow temperature range immediately above the critical temperature. The origin of this fluctuation regime is still unclear. A possibility is that it may be a precursor to a weakly first-order pairing transition. The evolution of this super-critical regime with pressure and magnetic field for our Ca-doped samples is distinct from results reported in the literature for pure and other divalent substituted YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}samples. Our results indicate that Ca doping favors the stabilization of the super-critical regime. (author)

Interdiffusion studies on high-Tc superconducting YBa2Cu3O7-δ thin films on Si(111) with a NiSi2/ZrO2 buffer layer

DEFF Research Database (Denmark)

Aarnink, W.A.M.; Blank, D.H.A.; Adelerhof, D.J.

1991-01-01

Interdiffusion studies on high-T(c) superconducting YBa2Cu3O7-delta thin films with thickness in the range of 2000-3000 angstrom, on a Si(111) substrate with a buffer layer have been performed. The buffer layer consists of a 400 angstrom thick epitaxial NiSi2 layer covered with 1200 angstrom...... of polycrystalline ZrO2. YBa2Cu3O7-delta films were prepared using laser ablation. The YBa2Cu3O7-delta films on the Si/NiSi2/ZrO2 substrates are of good quality; their critical temperatures T(c,zero) and T(c,onset) have typical values of 85 and 89 K, respectively. The critical current density j(c) at 77 K equaled 4...... x 10(4) A/cm2. With X-ray analysis (XRD), only c-axis orientation has been observed. The interdiffusion studies, using Rutherford backscattering spectrometry (RBS) and scanning Auger microscopy (SAM) show that the ZrO2 buffer layer prevents severe Si diffusion to the YBa2Cu3O7-delta layer, the Si...

The delta18O composition of Antarctic coastal current waters

International Nuclear Information System (INIS)

Frew, R.; Heywood, K.; Dennis, P.

1997-01-01

The varying proportions of 18 O to 16 O in sea water provide an oceanographic trace like salinity, but with an extra degree of freedom: salt is a tracer for the oceanic fluid, whereas the isotopic composition is a tracer specifically for the water component of that fluid. Hydrogen and oxygen isotopes are the variables most intimately related to the water component in the sea, therefore thay furnish a direct link to the water in the atmosphere and on continents and to the precipitation cycle which caused the salinity changes. The ratio of 18 O to 16 O (delta 18 O) ot waters is a powerful tracer in polar regions where sea and glacial ice processes decouple delta 18 O from salinity. Here we present observations from a significant but relatively unexplored component of the Southern Ocean current system, the Antarctic Coastal Current, and its associated Antarctic Slope Front. (author)

Growth and adult height in GH-treated children with nonacquired GH deficiency and idiopathic short stature: the influence of pituitary magnetic resonance imaging findings.

Science.gov (United States)

Coutant, R; Rouleau, S; Despert, F; Magontier, N; Loisel, D; Limal, J M

2001-10-01

We analyzed the final height of 146 short children with either nonacquired GH deficiency or idiopathic short stature. Our purpose was 1) to assess growth according to the pituitary magnetic resonance imaging findings in the 63 GH-treated children with GH deficiency and 2) to compare the growth of the GH-deficient patients with normal magnetic resonance imaging (n = 48) to that of 32 treated and 51 untreated children with idiopathic short stature (GH peak to provocative tests >10 microg/liter). The mean GH dose was 0.44 IU/kg.wk (0.15 mg/kg.wk), given for a mean duration of 4.6 yr. Among the GH-deficient children, 15 had hypothalamic-pituitary abnormalities (stalk agenesis), all with total GH deficiency (GH peak imaging, had better catch-up growth (+2.7 +/- 0.9 vs. +1.3 +/- 0.8 SD score; P imaging, there was no difference in catch-up growth and final height between partial and total GH deficiencies. GH-deficient subjects with normal magnetic resonance imaging and treated and untreated patients with idiopathic short stature had comparable auxological characteristics, age at evaluation, and target height. Although they had different catch-up growth (+1.3 +/- 0.8, +0.9 +/- 0.6, and +0.7 +/- 0.9 SD score, respectively; P imaging findings show the heterogeneity within the group of nonacquired GH deficiency and help to predict the response to GH treatment in these patients. The similarities in growth between the GH-deficient children with normal magnetic resonance imaging and those with idiopathic short stature suggest that the short stature in the former subjects is at least partly due to factors other than GH deficiency.

Growth hormone (GH)-releasing activity of chicken GH-releasing hormone (GHRH) in chickens.

Science.gov (United States)

Harvey, S; Gineste, C; Gaylinn, B D

2014-08-01

Two peptides with sequence similarities to growth hormone releasing hormone (GHRH) have been identified by analysis of the chicken genome. One of these peptides, chicken (c) GHRH-LP (like peptide) was previously found to poorly bind to chicken pituitary membranes or to cloned and expressed chicken GHRH receptors and had little, if any, growth hormone (GH)-releasing activity in vivo or in vitro. In contrast, a second more recently discovered peptide, cGHRH, does bind to cloned and expressed cGHRH receptors and increases cAMP activity in transfected cells. The possibility that this peptide may have in vivo GH-releasing activity was therefore assessed. The intravenous (i.v.) administration of cGHRH to immature chickens, at doses of 3-100 μg/kg, significantly increased circulating GH concentrations within 10 min of injection and the plasma GH levels remained elevated for at least 30 min after the injection of maximally effective doses. The plasma GH responses to cGHRH were comparable with those induced by human (h) or porcine (p) GHRH preparations and to that induced by thyrotropin releasing hormone (TRH). In marked contrast, the i.v. injection of cGHRH-LP had no significant effect on circulating GH concentrations in immature chicks. GH release was also increased from slaughterhouse chicken pituitary glands perifused for 5 min with cGHRH at doses of 0.1 μg/ml or 1.0 μg/ml, comparable with GH responses to hGHRH1-44. In contrast, the perifusion of chicken pituitary glands with cGHRH-LP had no significant effect on GH release. In summary, these results demonstrate that cGHRH has GH-releasing activity in chickens and support the possibility that it is the endogenous ligand of the cGHRH receptor. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of out-of-plane disorder on the superconductivity of Bi{sub 2}Sr{sub 2-x}La{sub x}CuO{sub 6+{delta}}

Energy Technology Data Exchange (ETDEWEB)

Roehler, Juergen; Trabant, Christoph; Frielingsdorf, Johanna; Djemour, Rabia [Universitaet Koeln, 50937 Koeln (Germany); Martovitsky, Victor [Lebedev-Institute, 119991 Moscow (Russian Federation); Dudy, Lenart; Dwelk, Helmut; Krapf, Alica [Humboldt Universitaet Berlin, 12489 Berlin (Germany)

2008-07-01

The effects of out-of-plane substitutional order/disorder on cuprate superconductivity remains to a large extent an unresolved issue. We have investigated the connection between superconductivity and the lattice effects arising from the heterovalent doping of Bi{sub 2}Sr{sub 2-x}La{sub x}CuO{sub 6+{delta}}, x = 0.8-0.1. Decreasing lanthanum content tunes the compound through the entire underdoped and overdoped regimes. Cu-K and La- K EXAFS served as local structural probes, and single crystal X-ray diffraction for the determination of the basic unit cell, and the symmetry of the supercell. The oxygen atoms in the CuO{sub 2} planes were found significantly disordered, dependent on doping, and to exhibit minimum disorder around x{sub opt}=0.33. But the degree of substitutional disorder in the out-of-plane La environment turned out independent on the concentration of the La dopants, the superstructure symmetry, and the crystal growth parameters, whereas T{sub c} depends sensitively on them. No evidence was found for possible concentration dependent site changes of the La dopant from the nominal Sr to the Bi sites. We discuss the probably crucial role of the interstitial oxygen atoms for the superconducting properties of the Bi{sub 2}Sr{sub 2-x}La{sub x}CuO{sub 6+{delta}} system.

The characterization of six auxin-induced tomato GH3 genes uncovers a member, SlGH3.4, strongly responsive to arbuscular mycorrhizal symbiosis.

Science.gov (United States)

Liao, Dehua; Chen, Xiao; Chen, Aiqun; Wang, Huimin; Liu, Jianjian; Liu, Junli; Gu, Mian; Sun, Shubin; Xu, Guohua

2015-04-01

In plants, the GH3 gene family is widely considered to be involved in a broad range of plant physiological processes, through modulation of hormonal homeostasis. Multiple GH3 genes have been functionally characterized in several plant species; however, to date, limited works to study the GH3 genes in tomato have been reported. Here, we characterize the expression and regulatory profiles of six tomato GH3 genes, SlGH3.2, SlGH3.3, SlGH3.4, SlGH3.7, SlGH3.9 and SlGH3.15, in response to different phytohormone applications and arbuscular mycorrhizal (AM) fungal colonization. All six GH3 genes showed inducible responses to external IAA, and three members were significantly up-regulated in response to AM symbiosis. In particular, SlGH3.4, the transcripts of which were barely detectable under normal growth conditions, was strongly activated in the IAA-treated and AM fungal-colonized roots. A comparison of the SlGH3.4 expression in wild-type plants and M161, a mutant with a defect in AM symbiosis, confirmed that SlGH3.4 expression is highly correlated to mycorrhizal colonization. Histochemical staining demonstrated that a 2,258 bp SlGH3.4 promoter fragment could drive β-glucuronidase (GUS) expression strongly in root tips, steles and cortical cells of IAA-treated roots, but predominantly in the fungal-colonized cells of mycorrhizal roots. A truncated 654 bp promoter failed to direct GUS expression in IAA-treated roots, but maintained the symbiosis-induced activity in mycorrhizal roots. In summary, our results suggest that a mycorrhizal signaling pathway that is at least partially independent of the auxin signaling pathway has evolved for the co-regulation of the auxin- and mycorrhiza-activated GH3 genes in plants. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Oxygen Nonstoichiometry and Defect Chemistry Modeling of Ce0.8Pr0.2O2-delta

DEFF Research Database (Denmark)

Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

2010-01-01

(DeltaHPrexc=aHdelta) and a completely random distribution of defects (referred to as “delta-linear”), or a “generalized delta-linear” solution model, where the excess Gibbs energy change in the reduction reaction of the dopant linearly varies with delta (DeltaGPrexc=aGdelta). A comparison of the partial...

The role of GH receptor tyrosine phosphorylation in Stat5 activation

DEFF Research Database (Denmark)

Hansen, J A; Hansen, L H; Wang, X

1997-01-01

Stimulation of GH receptors leads to rapid activation of Jak2 kinase and subsequent tyrosine phosphorylation of the GH receptor. Three specific tyrosines located in the C-terminal domain of the GH receptor have been identified as being involved in GH-stimulated transcription of the Spi 2.1 promoter....... Mutated GH receptors lacking all but one of these three tyrosines are able to mediate a transcriptional response when transiently transfected into CHO cells together with a Spi 2.1 promoter/luciferase construct. Similarly, these GH receptors were found to be able to mediate activation of Stat5 DNA......-binding activity, whereas the GH receptor mutant lacking all intracellular tyrosines was not. Synthetic tyrosine phosphorylated peptides corresponding to the GH receptor sequence around the three tyrosines inhibited Stat5 DNA-binding activity while their non-phosphorylated counterparts were ineffective. Tyrosine...

The basic route of the nuclear translocation porcine growth hormone (GH)-growth hormone receptor (GHR) complex (pGH/GHR) in porcine hepatocytes.

Science.gov (United States)

Hainan, Lan; Huilin, Liu; Khan, Mahamad; Xin, Zheng; YuJiang, Yang; Hui, Zhang; Naiquan, Yao

2018-06-08

Traditional views suggest that growth hormone and the growth hormone receptor (GH/GHR complex) exert their functions only on the plasma membrane. This paradigm, however, has been challenged by recent new findings that the GH/GHR complex could translocate into cell nuclei where they could still exhibit important physiological functions. We also reported the nuclear localization of porcine GH/GHR and their potential functions in porcine hepatocytes. However, the basic path of pGH/GHR's nuclear translocation remains unclear. Combining previous research results and our current findings, we proposed two basic routes of pGH/GHR's nuclear transportation as follows: 1) after pGH binding to GHR, pGH/GHR enters into the cytoplasm though clathrin- or caveolin-mediated endocytosis, then the pGH/GHR complex enters into early endosomes (Rab5-positive), and the endosome carries the GH/GHR complex to the endoplasmic reticulum (ER). After endosome docking on the ER, the endosome starts fission, and the pGH/GHR complex enters into the ER lumen. Then the pGH/GHR complex transports into the cytoplasm, possibly by the ERAD pathway. Subsequently, the pGH/GHR complex interacts with IMPα/β, which, in turn, mediates GH/GHR nuclear localization; 2) pGH binds with the GHR on the cell membrane and, subsequently, pGH/GHR internalizes into the cell and enters into the endosome (this endosome may belong to a class of endosomes called envelope-associated endosomes (NAE)). Then, the endosome carries the pGH/GHR to the nuclear membrane. After docking on the nuclear membrane, the pGH/GHR complex fuses with the nuclear membrane and then enters into the cell nucleus. Copyright © 2018 Elsevier Inc. All rights reserved.

CARACTERIZAÇÃO MORFOLÓGICA DO DELTA DO RIO DOCE (ES COM BASE EM ANÁLISE MULTISSENSOR

Directory of Open Access Journals (Sweden)

Silvia Palotti Polizel

2014-08-01

Full Text Available A costa leste brasileira apresenta uma sucessão de sistemas deltaicos, sendo o delta do rio Doce, localizado no Estado do Espírito Santo, um dos mais expressivos. A progradação principal deste delta, de geometria cuspidada típica de deltas de onda, tem sido atribuída à queda do nível do mar que se seguiu à transgressão holocênica média. Análises preliminares de novos produtos de sensoriamento remoto disponibilizados nesses últimos anos mostraram o potencial de aprimoramento do mapa geomorfológico desse delta, que pode contribuir para a melhor reconstituição paleoambiental e evolução desse sistema deposicional. Assim, este trabalho teve por objetivo fornecer um mapa geomorfológico detalhado para a planície costeira do rio Doce com base em dados multissensores integrando Modelo Digital de Elevação (MDE do Shuttle Radar Topography Mission (SRTM, Phased Array type L-band Synthetic Aperture Radar (PALSAR do Advanced Land Observing Satellite (ALOS, imagens TM/Landsat, além de imagens óticas de alta resolução extraídas do Google EarthTM. O mapeamento geomorfológico feito por interpretação visual resultou no estabelecimento de seis classes principais, designadas de: 1 drenagem atual; 2 cordão litorâneo/spit; 3 paleocanal; 4 planície interdistributária; 5 flúvio-estuarino/lagunar/marinho raso; e 6 terraço fluvial. De maneira geral, o emprego combinado dos produtos de sensoriamento produziu resultados satisfatórios para a separação dessas classes. O MDE-SRTM contribuiu para a identificação somente da classe paleocanais. As imagens PALSAR foram úteis na identificação das classes cordão litorâneo/spit, paleocanal, flúvio-estuarino/lagunar/marinho raso e terraço fluvial. As imagens TM/Landsat possibilitaram o reconhecimento das classes drenagem atual, cordão litorâneo/spit, planície interdistributária e flúvio-estuarino/lagunar/marinho raso. O mapa geomorfológico contribuiu na caracterização mais

Plasma lactate, GH and GH-binding protein levels in exercise following BCAA supplementation in athletes.

Science.gov (United States)

De Palo, E F; Gatti, R; Cappellin, E; Schiraldi, C; De Palo, C B; Spinella, P

2001-01-01

Branched chain amino acids (BCAA) stimulate protein synthesis, and growth hormone (GH) is a mediator in this process. A pre-exercise BCAA ingestion increases muscle BCAA uptake and use. Therefore after one month of chronic BCAA treatment (0.2 gkg(-1) of body weight), the effects of a pre-exercise oral supplementation of BCAA (9.64 g) on the plasma lactate (La) were examined in triathletes, before and after 60 min of physical exercise (75% of VO2 max). The plasma levels of GH (pGH) and of growth hormone binding protein (pGHBP) were also studied. The end-exercise La of each athlete was higher than basal. Furthermore, after the chronic BCAA treatment, these end-exercise levels were lower than before this treatment (8.6+/-0.8 mmol L(-1) after vs 12.8+/-1.0 mmol L(-1) before treatment; p BCAA chronic treatment, this end-exercise pGHBP was 738+/-85 pmol L(-1) before vs 1691+/-555 pmol L(-1) after. pGH/pGHBP ratio was unchanged in each athlete and between the groups, but a tendency to increase was observed at end-exercise. The lower La at the end of an intense muscular exercise may reflect an improvement of BCAA use, due to the BCAA chronic treatment. The chronic BCAA effects on pGH and pGHBP might suggest an improvement of muscle activity through protein synthesis.

Growth hormone (GH) effects on bone and collagen turnover in healthy adults and its potential as a marker of GH abuse in sports: a double blind, placebo-controlled study. The GH-2000 Study Group.

Science.gov (United States)

Longobardi, S; Keay, N; Ehrnborg, C; Cittadini, A; Rosén, T; Dall, R; Boroujerdi, M A; Bassett, E E; Healy, M L; Pentecost, C; Wallace, J D; Powrie, J; Jørgensen, J O; Saccà, L

2000-04-01

The effects of GH on bone remodeling in healthy adults have not been systematically investigated. An analysis of these effects might provide insights into GH physiology and might yield data useful for the detection of GH doping in sports. The aim of this study was to evaluate the effects of GH administration on biochemical markers of bone and collagen turnover in healthy volunteers. Ninety-nine healthy volunteers of both sexes were enrolled in a multicenter, randomized, double blind, placebo-controlled study and assigned to receive either placebo (40 subjects) or recombinant human GH (0.1 IU/kg day in 29 subjects and 0.2 IU/kg x day in 30 subjects). The treatment duration was 28 days, followed by a 56-day wash-out period. The biochemical markers evaluated were the bone formation markers osteocalcin and C-terminal propeptide of type I procollagen, the resorption marker type I collagen telopeptide, and the soft tissue marker procollagen type III. All variables increased on days 21 and 28 in the two active treatment groups vs. levels in both the baseline (P < 0.01) and placebo (P < 0.01) groups. The increment was more pronounced in the 0.2 IU/kg-day group and remained significant on day 84 for procollagen type III (from 0.53 +/- 0.13 to 0.61 +/- 0.14 kU/L; P < 0.02) and osteocalcin (from 12.2 + 2.9 to 14.6 +/- 3.6 UG/L; P < 0.02), whereas levels of C-terminal propeptide of type I procollagen and type I collagen telopeptide declined after day 42 and were no longer significantly above baseline on day 84 (from 3.9 +/- 1.2 to 5.1 +/-1.5 microg/L and from 174 +/- 60 to 173 +/- 53 microg/L, respectively). Gender-related differences were observed in the study; females were less responsive than males to GH administration with respect to procollagen type III and type I collagen telopeptide (P < 0.001). In conclusion, exogenous GH administration affects the biochemical parameters of bone and collagen turnover in a dose- and gender-dependent manner. As GH-induced modifications

Continuous infusion versus daily injections of growth hormone (GH) for 4 weeks in GH-deficient patients

DEFF Research Database (Denmark)

Laursen, Torben; Jørgensen, Jens Otto Lunde; Jakobsen, Grethe

1995-01-01

effects with constant and pulsatile GH delivery. This study was carried out to compare the metabolic effects of longer term continuous infusion vs. daily injections of GH. Thirteen GH-deficient patients were studied in a cross-over design. The patients were randomized to receive GH as a continuous sc...... infusion by means of a portable pump for 1 month and as daily sc injections (at 1900 h) for another month. An average daily GH dosage (+/- SEM) of 3.15 +/- 0.27 IU was administered during both periods. Steady state 24-h profiles of GH, IGF-I, IGF-binding proteins (IGFBPs), insulin, glucose, lipid.......35 (infusion); P infusion induced higher nighttime than daytime GH levels (P = 0.01), indicating a diurnal variation in the absorption or clearance of GH. Serum IGF-I levels (micrograms per L) were slightly higher (P infusion [312...

BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.1}Yb{sub 0.1}O{sub 3-{delta}} electrolyte-based solid oxide fuel cells with cobalt-free PrBaFe{sub 2}O{sub 5+{delta}} layered perovskite cathode

Energy Technology Data Exchange (ETDEWEB)

Ding, Hanping; Xue, Xingjian [Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

2010-10-15

A new anode-supported SOFC material system Ni-BZCYYb vertical stroke BZCYYb vertical stroke PBFO is investigated, in which a cobalt-free layered perovskite oxide, PrBaFe{sub 2}O{sub 5+{delta}} (PBFO), is synthesized and employed as a novel cathode while the synthesized BZCYYb is used as an electrolyte. The cell is fabricated by a simple dry-pressing/co-sintering process. The cell is tested and characterized under intermediate temperature range from 600 to 700 C with humified H{sub 2} ({proportional_to}3% H{sub 2}O) as fuel, ambient air as oxidant. The results show that the open-circuit potential of 1.006 V and maximal power density of 452 mW cm{sup -2} are achieved at 700 C. The polarization resistance of the electrodes is 0.18 {omega} cm{sup 2} at 700 C. Compared to BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.1}O{sub 3-{delta}}, the conductivity of co-doped barium zirconate-cerate BZCYYb is significantly improved. The ohmic resistance of single cell is 0.37 {omega} cm{sup 2} at 700 C. The results indicate that the developed Ni-BZCYYb vertical stroke BZCYYb vertical stroke PBFO cell is a promising functional material system for SOFCs. (author)

A remote but significant sequence homology between glycoside hydrolase clan GH-H and glycoside hydrolase family GH 31

DEFF Research Database (Denmark)

Janecek, S.; Svensson, Birte; MacGregor, E.A.

2007-01-01

Although both the α-amylase super-family, i.e. the glycoside hydrolase (GH) clan GH-H (the GH families 13, 70 and 77), and family GH31 share some characteristics, their different catalytic machinery prevents classification of GH31 in clan GH-H. A significant but remote evolutionary relatedness is...

Therapeutic Efficacy and Safety of GH in Japanese Children with Down Syndrome Short Stature Accompanied by GH Deficiency

OpenAIRE

Meguri, Kyoko; Inoue, Masaru; Narahara, Koji; Sato, Takahiro; Takata, Ami; Ohki, Nobuhiko; Ozono, Keiichi

2013-01-01

In this study, we investigated the effects of GH treatment in children with Down syndrome who had been diagnosed with GH deficiency (GHD). A total of 20 subjects were investigated in this study. Fourteen Down syndrome children (5 boys and 9 girls) with short stature due to GHD were treated with GH at Okayama Red Cross General Hospital, and 6 Down syndrome children (4 boys and 2 girls) with short stature due to GHD were registered in the Pfizer International Growth Database (KIGS). Height SD s...

Underlying physical aspects of fluctuations in YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} grain boundary Josephson junctions

Energy Technology Data Exchange (ETDEWEB)

Stornaiuolo, D. [CNR-INFM Coherentia, Dip. Scienze Fisiche, Universita di Napoli Federico II, 80125 Napoli (Italy); Gambale, E. [Dip. Ingegneria dell' Informazione, Seconda Universita di Napoli, 81031 Aversa (Italy); Bauch, T. [Department of Microelectronics and Nanoscience, MINA, Chalmers University of Technology, 41296 Goeteborg (Sweden); Born, D. [Dip. Ingegneria dell' Informazione, Seconda Universita di Napoli, 81031 Aversa (Italy); Cedergren, K. [Department of Microelectronics and Nanoscience, MINA, Chalmers University of Technology, 41296 Goeteborg (Sweden); Dalena, D. [Dip. Ingegneria dell' Informazione, Seconda Universita di Napoli, 81031 Aversa (Italy); Barone, A.; Tagliacozzo, A. [CNR-INFM Coherentia, Dip. Scienze Fisiche, Universita di Napoli Federico II, 80125 Napoli (Italy); Lombardi, F. [Department of Microelectronics and Nanoscience, MINA, Chalmers University of Technology, 41296 Goeteborg (Sweden); Tafuri, F. [CNR-INFM Coherentia, Dip. Scienze Fisiche, Universita di Napoli Federico II, 80125 Napoli (Italy); Dip. Ingegneria dell' Informazione, Seconda Universita di Napoli, 81031 Aversa (Italy)], E-mail: tafuri@na.infn.it

2008-02-15

High quality YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} biepitaxial grain boundary junctions allowed one of the first evidences of macroscopic quantum behavior and mesoscopic transport in high critical temperature superconductors (HTS) systems. Both these studies touch delicate issues on fluctuations and give important feedback on the understanding of coherent transport of quasiparticles and of the dissipation mechanisms in HTS.

Response to GH treatment in adult GH deficiency is predicted by gender, age, and IGF1 SDS but not by stimulated GH-peak

DEFF Research Database (Denmark)

Feldt-Rasmussen, Ulla; Brabant, Georg; Maiter, Dominique

2013-01-01

We studied whether the severity of GH deficiency (GHD) defined as i) GH-peak on stimulation tests (insulin tolerance test (ITT), arginine, and glucagon), ii) number of additional pituitary deficits, or iii) baseline IGF1 SDS could impact the response to GH treatment. We further explored whether iv...

GH and IGF1: roles in energy metabolism of long-living GH mutant mice.

Science.gov (United States)

Brown-Borg, Holly M; Bartke, Andrzej

2012-06-01

Of the multiple theories to explain exceptional longevity, the most robust of these has centered on the reduction of three anabolic protein hormones, growth hormone (GH), insulin-like growth factor, and insulin. GH mutant mice live 50% longer and exhibit significant differences in several aspects of energy metabolism as compared with wild-type mice. Mitochondrial metabolism is upregulated in the absence of GH, whereas in GH transgenic mice and dwarf mice treated with GH, multiple aspects of these pathways are suppressed. Core body temperature is markedly lower in dwarf mice, yet whole-body metabolism, as measured by indirect calorimetry, is surprisingly higher in Ames dwarf and Ghr-/- mice compared with normal controls. Elevated adiponectin, a key antiinflammatory cytokine, is also very likely to contribute to longevity in these mice. Thus, several important components related to energy metabolism are altered in GH mutant mice, and these differences are likely critical in aging processes and life-span extension.

SQUID picovoltometry of single crystal Bi2Sr2CaCu2O(8+delta) - Observation of the crossover from high-temperature Arrhenius to low-temperature vortex-glass behavior

Science.gov (United States)

Safar, H.; Gammel, P. L.; Bishop, D. J.; Mitzi, D. B.; Kapitulnik, A.

1992-04-01

A SQUID voltmeter has been used to measure current-voltage curves in untwinned crystals of Bi2Sr2CaCu2O(8+delta) as a function of temperature and magnetic field. The data show a clear crossover from high-temperature Arrhenius behavior to a critical region associated with the low-temperature three-dimensional vortex-glass phase transition. The critical exponents v(z - 1) = 7 +/- 1 in this system are in accord with theoretical models and previous measurements in YBa2Cu3O7. The width of the critical region collapses below 2 T, reflecting the changing role of dimensionality with field.

Nanoblast synthesis and consolidation of (La0.8Sr0.2)(Ga0.9Mg0.1)O(3-delta) under Spark plasma sintering conditions.

Science.gov (United States)

Vasylkiv, Oleg; Borodianska, Hanna; Badica, Petre; Zhen, Yongda; Tok, Alfred

2009-01-01

Four-cation nanograined strontium and magnesium doped lanthanum gallate (La0.8Sr0.2) (Ga0.9Mg0.1)O(3-delta) (LSGM) and its composite with 2 wt% of ceria (LSGM-Ce) were prepared. Morphologically homogeneous nanoreactors, i.e., complex intermediate metastable aggregates of desired composition were assembled by spray atomization technique, and subsequently loaded with nanoparticles of highly energetic C3H6N6O6. Rapid nanoblast calcination technique was applied and the final composition was synthesized within the preliminary localized volumes of each single nanoreactor on the first step of spark plasma treatment. Subsequent SPS consolidations of nanostructured extremely active LSGM and LSGM-Ce powders were achieved by rapid treatment under pressures of 90-110 MPa. This technique provided the heredity of the final structure of nanosize multimetal oxide, allowed the prevention of the uncontrolled agglomeration during multicomponent aggregates assembling, subsequent nanoblast calcination, and final ultra-rapid low-temperature SPS consolidation of nanostructured ceramics. LaSrGaMgCeO(3-delta) nanocrystalline powder consisting of approximately 11 nm crystallites was consolidated to LSGM-Ce nanoceramic with average grain size of approximately 14 nm by low-temperature SPS at 1250 degrees C. Our preliminary results indicate that nanostructured samples of (La0.8Sr0.2)(Ga0.9Mg0.1)O(3-delta) with 2 wt% of ceria composed of approximataley 14 nm grains can exhibit giant magnetoresistive effect in contrast to the usual paramagnetic properties measured on the samples with larger grain size.

Delayed release formulation of the somatostatin analog RC-160 inhibits the growth hormone (GH) response to GH-releasing factor-(1-29)NH2 and decreases elevated prolactin levels in rats.

Science.gov (United States)

Bokser, L; Schally, A V

1988-10-01

Recently, we have developed a long-acting delivery system for our somatostatin (SS) analog RC-160 based on injectable microcapsules in poly-(D,L-lactide-coglycolide). We studied the capacity of this formulation to repeatedly block the GH secretion induced by administration of GRF-(1-29)NH2 (GRF) on different days. Male rats anesthetized with pentobarbital were injected iv with 2.5 micrograms/kg BW GRF-(1-29)NH2 or saline. Five minutes later, blood samples were taken for GH measurement, and the animals were injected im with RC-160 microcapsules at a dose calculated to release 25 micrograms/day of the analog for 7 days or with the vehicle. The GRF stimuli were repeated 48 h, 96 h, and 8 days after administration of SS analog in microcapsules. GRF administration increased GH levels at the four times tested (P less than 0.01) in the control group injected with vehicle, while RC-160 microcapsules inhibited the GH response for more than 96 h (P less than 0.01). The GH levels augmented by pentobarbital were also decreased by the RC-160 microcapsules (P less than 0.01). Animals treated with microcapsules showed smaller increases in their body weight than untreated rats (P less than 0.05). We also investigated the effect of RC-160 microcapsules on hyperprolactinemic female rats implanted with pituitary glands under the kidney capsules. High PRL levels in rats bearing pituitary grafts showed a significant decrease when measured 4 days after the administration of RC-160 microcapsules. These results demonstrate the efficacy of the long-acting delivery system of the SS analog RC-160 and suggest the possible clinical usefulness of this formulation for lowering GH and PRL levels.

Formation of nanoparticles and defects in YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} prepared by the metal organic deposition process

Energy Technology Data Exchange (ETDEWEB)

Goswami, R. [Naval Research Laboratory, Washington, DC 20375 (United States); SAIC, Washington, DC 20003 (United States)], E-mail: goswami@anvil.nrl.navy.mil; Holtz, R.L. [Naval Research Laboratory, Washington, DC 20375 (United States); Rupich, M.W. [American Superconductors Inc., Westborough, MA 01581 (United States); Spanos, G. [Naval Research Laboratory, Washington, DC 20375 (United States)

2007-11-15

Nanoparticles and defects have been investigated using transmission electron microscopy in fully reacted YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO), prepared by the metal-organic deposition (MOD) process. Two types of particles, Y{sub 2}O{sub 3} and CuY{sub 2}O{sub 5}, ranging from 10 to 100 nm, have been observed in the YBCO matrix. The YBCO contains a large number of planar defects and a considerable number of (1 1 0) rotational twins. Details of the nanoparticles and defects in the MOD-processed YBCO films are presented in this paper.

GH-replacement therapy in adults

DEFF Research Database (Denmark)

Christiansen, J S; Jørgensen, J O; Pedersen, S A

1991-01-01

Growth hormone (GH) deficiency in adults, whether GH deficient since childhood or patients rendered GH deficient in adult life, is associated with psychosocial maladjustment, reduced muscle strength and reduced exercise capacity. Body composition is significantly altered with increased fat and de...

Particles on surfaces of laser ablated Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} films

Energy Technology Data Exchange (ETDEWEB)

Zheng, X.Y.; Zhu, S. [Tennessee Univ., Knoxville, TN (United States); Lowndes, D.H.; Warmack, R.J. [Oak Ridge National Lab., TN (United States)

1993-09-01

Pulsed laser deposition of Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} films grown at heater temperature of 720 and 800 C on SrTiO{sub 3} and MgO substrates with thickness ranging from a nominal 5 unit cells to 200 nm were studied by STM and SEM. Size and density of particles present in the films were found to depend on film thickness, growth temperature and substrate. STM images indicate a correlation between film growth mode and particle density: the onset of big particles comes after the growth mode changes from layer-like to island growth.

Controls of {delta}{sup 34}S and {delta}{sup 18}O in dissolved sulphate: Learning from a detailed survey in the Llobregat River (Spain)

Energy Technology Data Exchange (ETDEWEB)

Otero, Neus [Departament Cristal . lografia, Mineralogia i Diposits Minerals, Facultat de Geologia, Universitat de Barcelona, Marti i Franques, s/n, 08028 Barcelona (Spain); Grup d' Hidrogeoquimica, Departament de Geologia Ambiental, Institut de Ciencies de la Terra ' Jaume Almera' , CSIC, Lluis Sole i Sabaris, s/n, 08028 Barcelona (Spain)], E-mail: notero@ub.edu; Soler, Albert; Canals, Angels [Departament Cristal . lografia, Mineralogia i Diposits Minerals, Facultat de Geologia, Universitat de Barcelona, Marti i Franques, s/n, 08028 Barcelona (Spain)

2008-05-15

The S and O isotopic composition of dissolved SO{sub 4}, used as a tracer for SO{sub 4} sources, was applied to the water of the Llobregat River system (NE Spain). The survey was carried out at 30 sites where surface water was sampled on a monthly basis over a period of 2a. The concentration of dissolved SO{sub 4} varied from 20 to 1575 mg L{sup -1}. Sulphur isotopic compositions clustered in two populations: one - 93% of the samples - had positive values with a mode of +9 per mille ; the other had negative values and a mode of -5 per mille . Data for {delta}{sup 18}O{sub SO{sub 4}} showed a mean value of +11 per mille , with no bi-modal distribution, though lower values of {delta}{sup 18}O corresponded to samples with negative {delta}{sup 34}S. These values can not be explained solely by the contribution of bedrock SO{sub 4} sources: that is, sulphide oxidation and the weathering of outcrops of sulphates, though numerous chemical sediments exist in the basin. Even in a river with a high concentration of natural sources of dissolved SO{sub 4}, such as the Llobregat River, the {delta}{sup 34}S values suggest that dissolved SO{sub 4} is controlled by a complex mix of both natural and anthropogenic sources. The main anthropogenic sources in this basin are fertilizers, sewage, potash mine effluent and power plant emissions. Detailed river water sampling, together with the chemical and isotopic characterisation of the main anthropogenic inputs, allowed determination of the influence of redox processes, as well as identification of the contribution of natural and anthropogenic SO{sub 4} sources and detection of spatial variations and seasonal changes among these sources. For instance, in the Llobregat River the input of fertilisers is well marked seasonally. Minimum values of {delta}{sup 34}S are reported during fertilization periods - from January to March - indicating a higher contribution of this source. The dual isotope approach, {delta}{sup 34}S and {delta}{sup 18}O

A novel cobalt-free layered GdBaFe{sub 2}O{sub 5+{delta}} cathode for proton conducting solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Ding, Hanping; Xue, Xingjian [Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

2010-07-01

While cobalt-containing perovskite-type cathode materials facilitate the activation of oxygen reduction, they also suffer from problems like poor chemical stability in CO{sub 2} and high thermal expansion coefficients. In this research, a cobalt-free layered GdBaFe{sub 2}O{sub 5+{delta}} (GBF) perovskite was developed as a cathode material for protonic ceramic membrane fuel cells (PCMFCs) based on proton conducting electrolyte of stable BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY7). The button cells of Ni-BZCY7 vertical stroke BZCY7 vertical stroke GBF were fabricated and characterized using complex impedance technique from 600 to 700 C. An open-circuit potential of 1.007 V, maximum power density of 417 mW cm{sup -2}, and a low electrode polarization resistance of 0.18 {omega} cm{sup 2} were achieved at 700 C. The results indicate that layered GBF perovskite is a good candidate for cobalt-free cathode material, while the developed Ni-BZCY7 vertical stroke BZCY7 vertical stroke GBF cell is a promising functional material system for solid oxide fuel cells. (author)

Coulomb-Gas scaling law for a superconducting Bi(2+y)Sr(2-x-y)La(x)CuO(6+delta) thin films in magnetic fields

Science.gov (United States)

Zhang; Deltour; Zhao

2000-10-16

The electrical transport properties of epitaxial superconducting Bi(2+y)Sr(2-x-y)La(x)CuO(6+delta) thin films have been studied in magnetic fields. Using a modified Coulomb-gas scaling law, we can fit all the magnetic field dependent low resistance data with a universal scaling curve, which allows us to determine a relation between the activation energy of the thermally activated flux flow resistance and the characteristic temperature scaling parameters.

Atomic ordering of the fluorine dopant in the $HgBa_{2}CuO_{4+\\delta}high-T_{c}$ superconductor

CERN Document Server

Correia, João Guilherme; Araújo, João Pedro; Bordet, P; Haas, Heinz; Le Floc'h, S; Lopes, A M L; Rita, E; Carvalho-Soares, João

2005-01-01

Lattice sites and collective ordering of fluorine atoms in oxygen- reduced samples of HgBa/sub 2/CuO/sub 4/ were investigated with the perturbed angular correlation technique by measuring the electric field gradients induced at /sup 199m/Hg nuclei. The experimental data were interpreted with the help of ab initio calculations of charge distributions for different fluorine configurations in Hg/sub m/Ba /sub 2m/Cu/sub m/O/sub 4m/F/sub n/, supercells. Internal parameters were allowed to relax, to cancel residual atomic forces due to the dopant. The experimental results show clearly that fluorine occupies only the center of the mercury mesh. For a fluorine content delta F>~0.35 the best agreement with theoretical data is obtained under the assumption that fluorine shows a tendency toward ordering along interstitial rows parallel to a, b. In conformity with experimental data from diffraction techniques the calculations show elongations of the O(2)-Hg-O(2) dumbbell and barium shifts towards the fluorine atoms as ef...

Effects of 2 wk of GH administration on 24-h indirect calorimetry in young, healthy, lean men

DEFF Research Database (Denmark)

Hansen, Mette; Morthorst, Rikke; Larsson, Benny

2005-01-01

The present study was designed as a randomized, double-blind placebo (Plc)-controlled study to determine the effect of 2 wk of growth hormone administration (GH-adm.) on energy expenditure (EE) and substrate oxidation in healthy humans. Sixteen young healthy men were divided into two groups....... The study consisted of two 24-h measurements (indirect calorimetry), separated by 2 wk of either Plc or GH injections (6 IU/day). At baseline, no significant differences were observed between the two groups in any of the measured anthropometric, hormonal, or metabolic parameters, neither did the parameters...... change over time in the Plc group. GH-adm. resulted in a 4.4% increase in 24-h EE (P

Growth hormone (GH) treatment reverses early atherosclerotic changes in GH-deficient adults.

Science.gov (United States)

Pfeifer, M; Verhovec, R; Zizek, B; Prezelj, J; Poredos, P; Clayton, R N

1999-02-01

Hypopituitary patients have increased mortality from vascular disease, and in these patients, early markers of atherosclerosis [increased carotid artery intima-media thickness (IMT) and reduced distensibility] are more prevalent. As GH replacement can reverse some risk factors of atherosclerosis, the present study examined the effect of GH treatment on morphological and functional changes in the carotid and brachial arteries of GH-deficient (GHD) adults. Eleven GHD hypopituitary men (24-49 yr old) were treated with recombinant human GH (0.018 U/kg BW x day) for 18 months. IMT of the common carotid artery (CCA) and the carotid bifurcation (CB), and flow-mediated endothelium-dependent dilation (EDD) of the brachial artery were measured by B mode ultrasound before and at 3, 6, 12, and 18 months of treatment, and values were compared with those in 12 age-matched control men. Serum concentrations of lipids, lipoprotein(a), insulin-like growth factor I (IGF-I), and IGF-binding protein-3 (IGFBP-3) were also measured. In GHD men before treatment the IMTs of the CCA [mean(SD), 0.67(0.05) mm] and CB [0.75(0.04) mm] were significantly greater (P < 0.001) than those in control men [0.52(0.07) and 0.65(0.07) mm, respectively]. GH treatment normalized the IMT of the CCA by 6 months [0.53(0.04) mm] and that of the CB by 3 months [0.68(0.05) mm]. The IMT of the carotid artery (CCA and CB) was negatively correlated with serum IGF-I (r = -0.53; P < 0.0001). There was a significant improvement in flow-mediated EDD of the brachial artery at 3 months, which was sustained at 6 and 18 months of GH treatment (P < 0.05). GH treatment increased high density lipoprotein cholesterol at 3 and 6 months, but did not reduce total or low density lipoprotein cholesterol and was without effect on lipoprotein(a). There was no correlation between plasma lipids and changes in IMT or EDD of the arteries examined. In conclusion, GH treatment of hypopituitary GHD men reverses early morphological and

Femtosecond optical detection of quasiparticle dynamics in high- T sub c YBa sub 2 Cu sub 3 O sub 7 minus. delta. superconducting thin films

Energy Technology Data Exchange (ETDEWEB)

Han, S.G.; Vardeny, Z.V.; Wong, K.S.; Symko, O.G. (Department of Physics, University of Utah, Salt Lake City, UT (USA)); Koren, G. (Department of Physics, Technion, 32000 Haifa (Israel))

1990-11-19

Femtosecond dynamics of photogenerated quasiparticles in YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} superconducting thin films shows, at {ital T}{le}{ital T}{sub {ital c}}, two main electronic processes: (i) quasiparticle avalanche production during hot-carrier thermalization, which takes about 300 fsec; (ii) recombination of quasiparticles to form Cooper pairs, which is completed within 5 psec. In contrastr, nonsuperconducting epitaxial films such as PrBa{sub 2}Cu{sub 2}O{sub 7} and YBa{sub 2}Cu{sub 3}O{sub 6} show regular picosecond electronic response.

Diurnal Variations of Emissions of O2 singlet Delta Near Mars' Northern Summer Solstice

Science.gov (United States)

Nosowitz, Jonathon; Ziobron, Elijah; Novak, Robert E.

2017-10-01

We are presenting results of O2 singlet Delta emission, a tracer for ozone, in the Martian atmosphere for observations taken before Mars’ Northern summer solstice (Ls = 88o, February 10, 2014 ). The data were taken using CSHELL on the NASA-IRTF telescope located on Mauna Kea in Hawaii. The slit was positioned east-west on Mars and we observed diurnal variations at 20o N and 60o N. Spectral/spatial images were taken with a spectral resolution above 38,000. Mars’ relative velocity of -16 km/s enabled us to separate the Martian emission lines from the telluric absorption lines. Raw images were cleaned by removing dead and hot pixels. The images were then adjusted so that the spatial dimension was perpendicular to the spectral dimension. Extracts at 0.6 arcsec spatial resolution were taken which allowed us to measure Martian emission peaks. The Martian data were calibrated by taking similar observations from a standard star (HR4689) using the temperature, wavelength, and intensity of the star to calibrate the flux density. A Boltzmann analysis was performed on the observed emission peaks to obtain the rotational temperature of the excited O2. From this, the total emission rates were obtained. We found that at both latitudinal locations, the greatest emissions occured between 12:00- 13:00 local time on Mars. The emission intensity increases during the morning hours and then decreases towards sunset. We thank the administration and staff of the NASA-IRTF for observation time and for their assistance during operations of the telescope. We also thank Drs. M. Mumma and G. Villanueva of the NASA Goddard Space Flight Center with whom we collaborate.

Effects of growth hormone (GH) administration on homocyst(e)ine levels in men with GH deficiency: a randomized controlled trial.

Science.gov (United States)

Sesmilo, G; Biller, B M; Llevadot, J; Hayden, D; Hanson, G; Rifai, N; Klibanski, A

2001-04-01

GH deficiency is associated with increased cardiovascular mortality and early manifestations of atherosclerosis. Elevated serum homocyst(e)ine levels have been found to be associated with increased cardiovascular risk. The effect of GH replacement on homocyst(e)ine has not been investigated to date. We evaluated the effect of GH replacement on fasting homocyst(e)inemia in a group of men with adult-onset GH deficiency in a randomized, single blind, placebo-controlled trial. Forty men with adult-onset GH deficiency were randomized to GH or placebo for 18 months, with dose adjustments made according to serum insulin-like growth factor I (IGF-I) levels. Fasting serum homocyst(e)ine, folate, vitamin B12, and total T(3) levels were determined at baseline and 6 and 18 months. Anthropometry, IGF-I levels, insulin, and glucose were measured at 1, 3, 6, 12, and 18 months. Nutritional assessment, body composition, total T(4), thyroid hormone binding index, and free T(4) index were assessed every 6 months. Homocyst(e)ine decreased in the GH-treated group compared with that in the placebo group (net difference, -1.2 +/- 0.6 micromol/L; confidence interval, -2.4, -0.02 micromol/L; P = 0.047). Homocyst(e)ine at baseline was negatively correlated with plasma levels of folate (r = -0.41; P = 0.0087). Total T(3) increased in the GH-treated group vs. that in the placebo group (net difference, 0.17 +/- 0.046 ng/dL; confidence interval, 0.071, 0.26 nmol/L; P = 0.0012). Folate and vitamin B12 levels did not significantly change between groups. Changes in homocyst(e)ine were negatively correlated with changes in IGF-I. For each 1 nmol/L increase in IGF-I, homocyst(e)ine decreased by 0.04 +/- 0.02 micromol/L (P = 0.029). In contrast, changes in homocyst(e)ine did not correlate with changes in folate, vitamin B12, total T(3), C-reactive protein, interleukin-6, or insulin levels. This study shows that GH replacement decreases fasting homocyst(e)ine levels compared with placebo. This may be

Synthesis, magnetization and photocatalytic activity of LaFeO{sub 3} and LaFe{sub 0.5}Mn{sub 0.5-x}O{sub 3-{delta}}

Energy Technology Data Exchange (ETDEWEB)

Wei, Zhi-Xian, E-mail: zx_wei@126.com [Beijing Institute of Protective Materials and Technology, Beijing 100081 (China); School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Department of Chemistry, Science Institute, North University of China, Taiyuan, Shanxi 030051 (China); Wang, Yan [Department of Chemistry, Chengde Teachers College for Nationalities, Chengde, Hebei 067000 (China); Liu, Ji-Ping, E-mail: liujp@bit.edu.cn [Beijing Institute of Protective Materials and Technology, Beijing 100081 (China); School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Xiao, Cai-Mei; Zeng, Wei-Wei [Department of Chemistry, Science Institute, North University of China, Taiyuan, Shanxi 030051 (China)

2012-10-15

Perovskite LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} and LaFeO{sub 3} were synthesized by stearic acid solution combustion method. The obtained powders were characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), Vibrating sample magnetometer (VSM), XPS techniques and UV-vis absorption spectra techniques. The magnetic properties of the LaFeO{sub 3} and LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} were measured, and they were also evaluated for their photocatalytic activity towards the degradation of methyl orange (MO) under the sunlight irradiation. The experimental results show that the catalytic activities of the LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} were much higher than those of LaFeO{sub 3} due to its higher oxygen vacancies, variable valency Mn ions and the strong absorption in visible light. The optimum conditions for photocatalytic degradation MO using LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} were achieved. The ferromagnetism of the LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} could be caused by the Mn{sup 3+}/Fe{sup 3+} and Mn{sup 3+}/Mn{sup 4+}double exchange interaction, Mn{sup 3+}/Mn{sup 3+} superexchange interactions as well as the defective state in LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}}. The LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} is applicable to the magnetic separation process for its lower coercivity (Hc) and remanent magnetization (Mr), and it can be reusable and maintain relatively high activity. -- Highlights: Black-Right-Pointing-Pointer The LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} is a bifunctional photocatalyst. Black-Right-Pointing-Pointer The origin of the ferromagnetism of the LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} is discussed. Black-Right-Pointing-Pointer LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} shows much higher photocatalytic activity than that of LaFeO{sub 3.} Black-Right-Pointing-Pointer LaFe{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} can be recycled by an external magnetic

Study of LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) double perovskites as new cathode material for IT-SOFC

Energy Technology Data Exchange (ETDEWEB)

Chavez, E; Mueller, M; Mogni, L; Caneiro, A, E-mail: mogni@cab.cnea.gov.a [Centro Atomico Bariloche-CNEA, Instituto Balseiro. Av. Bustillo 9500, S. C. de Bariloche 8400 (Argentina)

2009-05-01

Oxides with double perovskites structures of general composition LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) were synthesized by solid state reaction with the purpose to evaluate new materials to be used as cathodes in intermediate temperature solid oxide fuel cell (IT-SOFC). A preliminary study about electrochemical properties was performed by impedance spectroscopy between 500 and 800 deg. C under atmosphere of pure O{sub 2}. Symmetrical cells were obtained by spray deposition of LnBaCo{sub 2}O{sub 6-d}elta (Ln = Pr, Nd, Sm and Gd) at both sides of a dense ceramic electrolyte. The impedance spectroscopy measurements as a function of temperatures show a hysteresis loop which could be associated to a tetragonal/orthorhombic phase transition. The existence of this transition was corroborated by high temperature X-Ray diffraction and Differential Scanning Calorimetry measurements.

Long-term effects of growth hormone (GH) replacement in men with childhood-onset GH deficiency

NARCIS (Netherlands)

ter Maaten, JC; De Boer, H; Kamp, O; Stuurman, L; Van der Veen, EA

Short term GH replacement therapy has been shown to improve body composition and exercise capacity. It is not yet known whether GH replacement remains beneficial over the long term. We assessed the effects of long term GH replacement on body composition, bone mineral density, and cardiac function.

Regulation of His-dTrp-Ala-Trp-dPhe-Lys-NH2 (GHRP-6)-induced GH secretion in the rat.

Science.gov (United States)

Mallo, F; Alvarez, C V; Benitez, L; Burguera, B; Coya, R; Casanueva, F F; Dieguez, C

1993-01-01

His-dTrp-Ala-Trp-dPhe,Lys-NH2(GHRP-6) is a synthetic compound that releases GH in a dose-response and specific manner in several species and that may well be related to an endogenous compound of similar structure. The aim of this study was to investigate the in vivo GH responses to GHRP-6 in pentobarbital anesthetized rats. Specifically and in order to avoid the influence of endogenous GHRH and somatostatin secretion we studied the GH responses to GHRP-6 in animals with surgical ablation of the hypothalamus, confirmed by histological assessment, as well as in hypophysectomyzed-transplanted rats bearing two hypophyses under the renal capsule. Since it has been previously reported that rats pretreated with GHRH (10 micrograms/kg i.p. every 12 h for 15 days) rather than saline-treated rats have greater GH responses to acutely administered GHRH, we compared the self-potentiating effect of chronic GH pretreatment with GHRP-6 (10 micrograms/kg i.p. every 12 h). Furthermore we also studied the influence of estrogens, glucocorticoids, free fatty acids (FFA) and bombesin on somatotroph responsiveness to GHRP-6 in intact rats. We found a greater GH response to GHRP-6 in rats that underwent a surgical ablation of the hypothalamus 36 h prior to the test than in sham-operated rats. A direct stimulatory effect of GHRP-6 on in vivo GH secretion was demonstrated by a clear GH response to GHRP-6 in hypophysectomyzed-transplanted rats. In addition, we found a similar response whether the animals were pretreated with GHRH or GHRP-6 over the previous 2 weeks. Finally, we found that both estrogen- and testosterone-treated rats have greater GH responses to GHRP-6 than untreated rats. On the other hand, chronic dexamethasone administration, acute elevation of circulating FFA levels and bombesin administration markedly inhibited GH responses to GHRP-6. In contrast to the effects exerted on GH responses to GHRP-6 estrogen administration led to a decrease in GH responses to GHRH while

Growth of superconducting Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} films by sedimentation deposition and liquid phase sintering and annealing technique

Energy Technology Data Exchange (ETDEWEB)

Manahan, R.L.C. [Condensed Matter Physics Laboratory, National Institute of Physics, University of the Philippines, Llamas Science Hall, Rm. 3122, E. Quirino Street, Diliman, Quezon City 1101 (Philippines)]. E-mail: rcmanahan@nip.upd.edu.ph; Sarmago, R.V. [Condensed Matter Physics Laboratory, National Institute of Physics, University of the Philippines, Llamas Science Hall, Rm. 3122, E. Quirino Street, Diliman, Quezon City 1101 (Philippines)

2006-10-01

We report on a technique of growing highly c-axis oriented Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} (Bi-2212) thick films on MgO substrate using a combined sedimentation-deposition and liquid phase sintering and annealing process. The temperature profiles employed partial melting followed by rapid cooling to temperature below the melting point. Scanning electron micrographs show that the films have a smooth surface. No evidence of grain boundaries on the film's surface can be seen. The critical temperatures of the samples range from {approx}67 K to {approx}81 K. This method presents a quick and easy preparation for high quality epitaxial Bi-2212 films.

Growth Hormone (GH) and Cardiovascular System

Science.gov (United States)

Díaz, Oscar; Devesa, Pablo

2018-01-01

This review describes the positive effects of growth hormone (GH) on the cardiovascular system. We analyze why the vascular endothelium is a real internal secretion gland, whose inflammation is the first step for developing atherosclerosis, as well as the mechanisms by which GH acts on vessels improving oxidative stress imbalance and endothelial dysfunction. We also report how GH acts on coronary arterial disease and heart failure, and on peripheral arterial disease, inducing a neovascularization process that finally increases flow in ischemic tissues. We include some preliminary data from a trial in which GH or placebo is given to elderly people suffering from critical limb ischemia, showing some of the benefits of the hormone on plasma markers of inflammation, and the safety of GH administration during short periods of time, even in diabetic patients. We also analyze how Klotho is strongly related to GH, inducing, after being released from the damaged vascular endothelium, the pituitary secretion of GH, most likely to repair the injury in the ischemic tissues. We also show how GH can help during wound healing by increasing the blood flow and some neurotrophic and growth factors. In summary, we postulate that short-term GH administration could be useful to treat cardiovascular diseases. PMID:29346331

Changes in growth hormone (GH) messenger RNA (GH mRNA) expression in the rat anterior pituitary after single interferon (IFN) alpha administration

International Nuclear Information System (INIS)

Romanowski, W.; Braczkowski, R.; Nowakowska-Zajdel, E.; Muc-Wierzgon, M.; Zubelewicz-Szkodzinska, B.; Kosiewicz, J.; Korzonek, I.

2006-01-01

Introduction: Interferon a (IFN-a) is a cytokine with pleiotropic effects which, via different pathways, influences the secretion of certain cytokines and hormones. Growth hormone (GH) secreted from the pituitary has physiological effects on various target tissues. The question is how IFN-a administered in various types of disease influences GH secretion. This study investigated the acute effect of IFN-a on GH mRNA expression in the rat anterior pituitary. Objective: The aim of the study was to measure the cellular expression of GH mRNA by in situ hybridisation in the anterior pituitary after a single administration of IFN-a. Material and methods: Rats were administered an intraperitoneal injection of IFN-a or saline. The rat pituitaries were taken 2 and 4 hours after IFN/saline administration and kept frozen until in situ hybridisation histochemistry. A 31 - base 35S -labelled oligonucleotide probe complementary to part of the exonic mRNA sequence coding for GH mRNA was used. All control and experimental sections were hybridised in the same hybridisation reaction. Results: Acute administration of interferon a increased GH mRNA expression in the anterior pituitary in the 4-hour group in comparison with the control group, and there was no difference between the control group and the 2-hour rats. Conclusion: A single IFN-a administration was found to exert an influence on anterior pituitary GH mRNA expression. These observations may pave the way for presenting a possible new action of IFN-a. (author) GH mRNA, anterior pituitary, interferon

Core level photoemission spectroscopy and chemical bonding in Sr2Ta2O7

DEFF Research Database (Denmark)

Atuchin, V. V.; Grivel, Jean-Claude; Zhang, Z. M.

2009-01-01

Electronic parameters of constituent element core levels of strontium pyrotantalate (Sr2Ta2O7) were measured with X-ray photoelectron spectroscopy (XPS). The Sr2Ta2O7 powder sample was synthesized using standard solid state method. The valence electron transfer on the formation of the Sr-O and Ta......-O bonds was characterized by the binding energy differences between the O 1s and cation core levels, Delta(O-Sr) = BE(O 1s) - BE(Sr 3d(5/2)) and Delta(O-Ta) = BE(O 1s) - BE(Ta 4f(7/2)). The chemical bonding effects were considered on the basis of our XPS results for Sr2Ta2O7 and earlier published...

EXPANSIÓN Y DIVERGENCIA DEL LOCUS GH ENTRE EL MONO ARAÑA Y EL CHIMPANCÉ

OpenAIRE

DE MENDOZA, AGNÈS; ESQUIVEL, DOLORES; MARTÍNEZ, IRMA; BARRERA, HUGO

2005-01-01

Para precisar la historia muy particular de la hormona del crecimiento (GH) en los primates, se describieron los loci GH del mono araña, un mono del Nuevo Mundo y del chimpancé, una especie cercana al humano. Al menos seis genes integran ambos loci GH: todos del tipo GH en el mono araña, y dos GHs y cuatro lactógenos placentarios (PLs) en el chimpancé. Las regiones intergénicas del locus del chimpancé presentan un tamaño mayor a las del mono araña. Este trabajo conf...

Hypophysectomy eliminates and growth hormone (GH) maintains the midpregnancy elevation in GH receptor and serum binding protein in the mouse

International Nuclear Information System (INIS)

Sanchez-Jimenez, F.; Fielder, P.J.; Martinez, R.R.; Smith, W.C.; Talamantes, F.

1990-01-01

[ 125 I]Iodomouse GH [( 125 I]iodo-mGH) binding to samples of serum and hepatic microsomal membranes was measured in hypophysectomized pregnant, sham-operated pregnant, intact pregnant, and intact adult virgin mice. Surgeries were carried out on day 11 of pregnancy, and the animals were killed on day 14. The binding of mGH to both serum and hepatic microsomal membranes of intact virgin mice was much lower than to those of intact pregnant mice. In hypophysectomized mice, the mGH-binding capacity of both serum and hepatic microsomes decreased to values similar to those of nonpregnant mice. No significant differences were observed between intact and sham-operated pregnant animals in the maternal serum mGH concentration, the serum GH-binding protein concentration, or the hepatic GH receptor concentration. GH receptor and binding protein-encoding mRNAs were also higher in intact and sham-operated pregnant mice than in virgin and hypophysectomized mice. Hypophysectomized mice were treated with 200 micrograms/day bovine GH, administered by osmotic minipump; after 3 days of treatment, a significant elevation of hepatic GH receptor and serum GH-binding protein levels was observed. These results demonstrate an up-regulation of hepatic GH receptors and serum GH-binding protein by GH during pregnancy in the mouse

Epitaxial growth of YBa sub 2 Cu sub 3 O sub 7 minus. delta. thin films on LiNbO sub 3 substrates

Energy Technology Data Exchange (ETDEWEB)

Lee, S.G.; Koren, G.; Gupta, A.; Segmuller, A.; Chi, C.C. (IBM Thomas J. Watson Research Center, P.O. Box 218, Yorktown Heights, New York 10598 (US))

1989-09-18

{ital In} {ital situ} epitaxial growth of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} thin films on {ital Y}-cut LiNbO{sub 3} substrates using a standard laser ablation technique is reported. Resistance of the films shows a normal metallic behavior and a very sharp ({lt}1 K) superconducting transition with {ital T}{sub {ital c}}({ital R}=0) of 92 K. High critical current density of {ital J}{sub {ital c}}(77 K)=2{times}10{sup 5} A/cm{sup 2} is observed, which is in accordance with epitaxial growth. Film orientation observed from x-ray diffraction spectra indicates that the {ital c} axis is normal to the substrate plane and the {ital a} axis is at 45{degree} to the (11.0) direction of the hexagonal lattice of the substrate with two domains in mirror image to the (110) plane.

Anti-bombing insensitivity life of molybdenum cathode doped with La{sub 2}O{sub 3} and Y{sub 2}O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Wang Jinshu [School of Materials Science and Engineering, Beijing University of Technology, Beijing 100022 (China)]. E-mail: wangjsh@bjut.edu.cn; Wang Yiman [School of Materials Science and Engineering, Beijing University of Technology, Beijing 100022 (China); Zhou Meiling [School of Materials Science and Engineering, Beijing University of Technology, Beijing 100022 (China)

2006-03-15

Anti-bombing insensitivity of La{sub 2}O{sub 3}-Y{sub 2}O{sub 3}-Mo secondary emitter has been studied in this paper. The variation of maximum secondary emission coefficient {delta} {sub max} with time was measured. The cathode after life experiment was analyzed by means of HRM, SEM, EDS and XRD. The results showed that {delta} {sub max} of La{sub 2}O{sub 3}-Y{sub 2}O{sub 3}-Mo cathode operating at 1100 deg. C under continuous electron bombardment of 300 W/cm{sup 2} was still about 2.5 after 1000 h operation, indicating that this kind of cathode had good anti-bombing insensitivity. In the internal part of the cathode, RE{sub 2}O{sub 3} (rare earth oxide) and molybdenum grains distributed alternately and there existed a certain relationship between crystallographic orientation of RE{sub 2}O{sub 3} and that of molybdenum. It was found that a RE{sub 2}O{sub 3} layer was formed on the surface after operation. The high {delta} {sub max} of La{sub 2}O{sub 3}-Y{sub 2}O{sub 3}-Mo cathode was related to the RE{sub 2}O{sub 3} layer on the surface and the amount of nanosized La{sub 2}O{sub 3} particles on the Y{sub 2}O{sub 3} layer.

Cirugía transesfenoidal: primera opción de tratamiento para adenomas hipofisarios secretores de GH Transsphenoidal surgery: first treatment option for GH secreting hypophyseal adenomas

OpenAIRE

Omar López Arbolay; Justo Luis González González; Osmany Morales Sabina; Lorenzo Nedel Valdés

2004-01-01

La elevación de los niveles de hormona del crecimiento (GH) promueve el crecimiento grotesco de partes acras (acromegalia) o incremento de la talla (gigantismo) según la edad, así como trastornos metabólicos de relevancia biológica. La adenomectomía selectiva clasifica entre las modalidades de tratamiento. El objetivo del presente trabajo fue evaluar los resultados del tratamiento microquirúrgico por vía transeptoesfenoidal de los adenomas productores de GH en nuestro medio. Presentamos un es...

Defective membrane expression of human growth hormone (GH) receptor causes Laron-type GH insensitivity syndrome.

Science.gov (United States)

Duquesnoy, P; Sobrier, M L; Amselem, S; Goossens, M

1991-01-01

Mutations in the growth hormone receptor (GHR) gene can cause growth hormone (GH) resistance. Given the sequence homology between the extracellular domain of the GHR and a soluble GH-binding protein (GH-BP), it is remarkable that GH-BP binding activity is absent from the serum of patients with Laron-type GH insensitivity, a hereditary form of severe dwarfism. We have previously identified a mutation within the extracellular domain of this receptor, replacing phenylalanine by serine at position 96 of the mature protein, in a patient with Laron syndrome. We have now investigated the effect of this Phe----Ser substitution on hormone binding activity by expressing the total human GHR cDNA and mutant form in eukaryotic cells. The wild-type protein expressed was able to bind GH but no plasma membrane binding was detectable on cells transfected with the mutant cDNA; this was also the case of cells transfected with a Phe96----Ala mutant cDNA, suggesting that the lack of binding activity is not due to a posttranslational modification of serine. Examination of the variant proteins in subcellular fractions revealed the presence of specific GH binding activity in the lysosomal fraction, whereas immunofluorescence studies located mutant proteins in the cytosol. Our findings suggest that these mutant GHRs fail to follow the correct intracellular transport pathway and underline the potential importance of this phenylalanine residue, which is conserved among the GH, prolactin, and erythropoietin receptors that belong to the same cytokine receptor superfamily. Images PMID:1719554

Pioglitazone treatment increases spontaneous growth hormone (GH) secretion and stimulated GH levels in polycystic ovary syndrome

DEFF Research Database (Denmark)

Glintborg, Dorte; Støving, René Klinkby; Hagen, Claus

2005-01-01

BACKGROUND: Low GH levels, probably due to insulin resistance and increased abdominal fat mass, are well described in polycystic ovary syndrome (PCOS). GH acts as an important ovarian cogonadotropin, and GH disturbances may be an additional pathogenic factor in PCOS. Decreased abdominal fat mass...

Combustion behaviors of GO2/GH2 swirl-coaxial injector using non-intrusive optical diagnostics

Science.gov (United States)

GuoBiao, Cai; Jian, Dai; Yang, Zhang; NanJia, Yu

2016-06-01

This research evaluates the combustion behaviors of a single-element, swirl-coaxial injector in an atmospheric combustion chamber with gaseous oxygen and gaseous hydrogen (GO2/GH2) as the propellants. A brief simulated flow field schematic comparison between a shear-coaxial injector and the swirl-coaxial injector reveals the distribution characteristics of the temperature field and streamline patterns. Advanced optical diagnostics, i.e., OH planar laser-induced fluorescence and high-speed imaging, are simultaneously employed to determine the OH radical spatial distribution and flame fluctuations, respectively. The present study focuses on the flame structures under varying O/F mixing ratios and center oxygen swirl intensities. The combined use of several image-processing methods aimed at OH instantaneous images, including time-averaged, root-mean-square, and gradient transformation, provides detailed information regarding the distribution of the flow field. The results indicate that the shear layers anchored on the oxygen injector lip are the main zones of chemical heat release and that the O/F mixing ratio significantly affects the flame shape. Furthermore, with high-speed imaging, an intuitionistic ignition process and several consecutive steady-state images reveal that lean conditions make it easy to drive the combustion instabilities and that the center swirl intensity has a moderate influence on the flame oscillation strength. The results of this study provide a visualized analysis for future optimal swirl-coaxial injector designs.

Study by neutrons diffusion and X-rays of structural and magnetic properties of Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+4+{delta}} type superconductive cuprates; Etude par diffusion des neutrons et des rayons X des proprietes structurales et magnetiques des cuprates supraconducteurs de type Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+4+{delta}}

Energy Technology Data Exchange (ETDEWEB)

Vasiliu-Doloc, L

1995-09-22

In this work we have used inelastic and elastic neutron and X-ray scattering techniques for characterizing the incommensurate structural distortions in compounds belonging to the family Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+4+{delta}} of high-Tc superconducting cuprates. We have searched the existence of structural instabilities specific of the CuO{sub 2} planes and of magnetic instabilities. The modulated structure of the 2212 phase has been refined from single-crystal neutron diffraction results and importance of distortion of CuO{sub 2} planes has thus been determined. It is shown that the additional oxygen is not ordered three-dimensionally within the modulated structure and that the information about it is contained in diffuse scattering results. A model of the short-range order associated with additional oxygen atoms is proposed and discussed. The temperature studies of the long-range order have shown a great stability of the amplitude and period of the incommensurate distortion wave in the one-layer, as well as in the double-layer compounds, either superconducting or insulating. We find such a behaviour to be highly incompatible with a distortion resulting from a charge-density-wave instability. The results we have obtained indicate that the bismuth-based high-Tc superconducting cuprates have essentially the same physics of the CuO{sub 2} planes as the previous two families, La{sub 2-x}Sr{sub x}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 6+{delta}}, being at the proximity of three instabilities: a metal-insulator transition, an antiferromagnetic instability and a structural instability specific of the CuO{sub 2} planes. (author).

Changes in modulation period of Bi sub 2 Sr sub 2 (Ca sub 1-x Nd sub x )Cu sub 2 O sub 8+. delta. and their relations to oxygen content

Energy Technology Data Exchange (ETDEWEB)

Onozuka, Takashi; Tokiwa, Ayako; Syono, Yasuhiko (Inst. for Materials Research, Tohoku Univ., Sendai (Japan)); Koike, Yoji; Saito, Yoshitami (Dept. of Applied Physics, Tohoku Univ., Sendai (Japan))

1991-12-01

Structural changes of long-period modulated structure (LPMS) of the Bi{sub 2}Sr{sub 2}(Ca{sub 1-x}Nd{sub x})Cu{sub 2}O{sub 8+{delta}} ceramics with x are investigated by means of electron diffraction. Increasing x, the modulation mode of the mixing of domains of two modulation periods with b=4.5b{sub o} and b=5b{sub o} changes to that with b=4.5b{sub o} and b=4b{sub o} through the modulation mode with only b=4.5b{sub o} at x=0.4-0.5. The wavenumber of the superlattice reflection shows a stepwise increase rather than a linear increase with x. Excess oxygen in a LPMS model with the site of excess oxygen is shown to be consistent with excess oxygen analyzed chemically by iodometry and its change with x. (orig.).

Room temperature ferromagnetism in Th{sub 1-x}Fe{sub x}O{sub 2-{delta}} (x = 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Jayakumar, O.D. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Gopalakrishnan, I.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)], E-mail: ikgopal@barc.gov.in; Vinu, A. [Nano-Ionics Materials Group, Fuel Cell Materials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Asthana, A. [Advanced Electron Microscopy Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2008-08-11

Nanocrystalline (Th{sub 1-x}Fe{sub x})O{sub 2-{delta}} particles with different Fe concentrations (x = 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) have been prepared by a gel combustion method. Rietveld refinement analyses of X-ray diffraction data revealed the formation of an impurity free cubic type Th{sub 1-x}Fe{sub x}O{sub 2-{delta}} structure up to x = 0.20. This observation is further confirmed from the detailed studies conducted on 10 at.% Fe doped ThO{sub 2} using high-resolution transmission electron microscopy (HRTEM) imaging and indexing of the selected-area electron diffraction (SAED) patterns. DC magnetization studies as a function field indicate that they are ferromagnetic with Curie temperature (T{sub c}) well above room temperature.

Magnetic penetration depth of YBa2Cu3O(7-delta) thin films determined by the power transmission method

Science.gov (United States)

Heinen, Vernon O.; Miranda, Felix A.; Bhasin, Kul B.

1992-01-01

A power transmission measurement technique was used to determine the magnetic penetration depth (lambda) of YBa2Cu3O(7-delta) superconducting thin films on LaAlO3 within the 26.5 to 40.0 GHz frequency range, and at temperatures from 20 to 300 K. Values of lambda ranging from 1100 to 2500 A were obtained at low temperatures. The anisotropy of lambda was determined from measurements of c-axis and a-axis oriented films. An estimate of the intrinsic value of lambda of 90 +/- 30 nm was obtained from the dependence of lambda on film thickness. The advantage of this technique is that it allows lambda to be determined nondestructively.

Perturbed angular correlations studies in the HgBa$_2$CaCu$_2$O$_{6+\\delta}$ high-T$_c$ superconductor

CERN Document Server

Mendonca, Tania Melo; Haas, Heinz; Odier, Philippe; Tavares, Pedro; SIlva, Manuel Ribeiro; Lopes, Armandina; Darie, Celine; Araujo, Joao Pedro

2011-01-01

The electric field gradients at $^{199m}$Hg nuclei have been measured via the perturbed angular correlation (PAC) technique, allowing a full characterization of the Hg neighborhood charge distribution at high oxygen doping on the Hg planes. The PAC technique has been applied to investigate the effect of high oxygen pressure during the measurement. Polycrystalline HgBa$_2$CaCu$_2$O$_{6+\\delta}$ (Hg-1212) samples have been annealed at 152 bar pressurized oxygen. The influence of oxygen pressure during the experiment was then investigated by measuring the samples at atmospheric pressure and under 152 bar oxygen pressure. The present set of PAC experiments shows that at high oxygen concentrations there is a non-uniform oxygen distribution. Moreover, the Hg environment is not free from oxygen and the results hint to a new type of ordering.

[Characterizing spatial patterns of NO(x), SO2 and O3 in Pearl River Delta by passive sampling].

Science.gov (United States)

Zhao, Yang; Shao, Min; Wang, Chen; Wang, Bo-Guang; Lu, Si-Hua; Zhong, Liu-Ju

2011-02-01

Concentrations of NO(x), SO2 and O3 were measured by passive sampling within 200km x 200km grid in Pearl River Delta (PRD). Sampling period was two weeks in November, 2009. Spatial distributions of NO(x), SO2 and O3 were obtained by Kriging interpolation method. The results were compared with emission inventories and modeling results. The transportations of O3 were evaluated by using backward trajectories of air parcels. During the sampling period, the mean concentrations of NO(x), SO2 and O3 were 75.9 microg/m3, 37.3 microg/m3 and 36.2 microg/m3, respectively. And the highest concentrations of NO(x), SO2 and O3 were 195.7 microg/m3, 95.9 microg/m3 and 81.8 microg/m3. Comparing with routine measurements from the regional monitoring network in PRD, the results by passive method were 18.6%, 33.5% and 37.5% lower for NO(x), SO2 and O3, respectively. The spatial patterns demonstrated that higher NO(x) concentrations often appeared in cities such as Guangzhou, Foshan and Shenzhen. SO2 concentrations were higher in west and lower in east. High SO2 concentrations are mainly from emission of power plants and industrial sources. Concentrations of O3 showed the highest levels in the south of PRD. Backward trajectory analysis for higher ozone areas indicated that 53% of the air masses were from the region with high concentration of NO(x). The horizontal transportation caused higher ozone in the south while lower in north in PRD.

In-plane dissipation maxima and vortex-line distortions in the resistive transitions of oxygen-doped Bi2Sr2CaCu2O(8+delta) single crystals

Science.gov (United States)

Hsu, J. W. P.; Mitzi, D. B.; Kapitulnik, A.; Lee, Mark

1991-10-01

Measurements of the in-plane resistive transition of Bi2Sr2CaCu2O(8+delta) single crystals in perpendicular magnetic fields reveal that in oxygen-reduced samples a giant resistance maximum evolves with field. This is not seen in oxygenated samples with similar metallic normal resistivities. As the peak resistivity may exceed the normal resistivity, it cannot arise from ordinary vortex-motion dissipation. A model is proposed where the excess resistance results from nonrigid vortex motion coupling the out-of-plane dissipation to the in-plane resistance at temperatures where pinning effects are negligible.

Growth and Properties of Oxygen and Ion Doped BISMUTH(2) STRONTIUM(2) Calcium COPPER(2) Oxygen (8+DELTA) Single Crystals

Science.gov (United States)

Mitzi, David Brian

1990-01-01

A directional solidification method for growing large single crystals in the Bi_2Sr _2CaCu_2O _{8+delta} system is reported. Ion substitutions, with replacement of La for Sr and Y for Ca, as well as oxygen doping in these crystals has been explored. Ion doping results in little change of the superconducting transition for substitution levels below 20-25% (as a result of simultaneous oxygen intercalation), while beyond this level, the Meissner signal broadens and the low temperature Meissner signal decreases. Microprobe analysis and x-ray diffraction performed on these more highly substituted single crystals, provides evidence for inhomogeneity and phase segregation into regions of distinct composition. Annealing unsubstituted crystals in increasing partial pressures of oxygen reversibly depresses the superconducting transition temperature from 90K (as made) to 77K (oxygen pressure annealed) while the Hall concentrations increase from n = 3.1(3) times 10 ^{21} cm^{ -3} (0.34 holes/Cu site) to 4.6(3) times 10^{21} cm^{-3} (0.50 holes/Cu site). Further suppression of T_{c} to 72K is possible by annealing in oxygen pressures up to 100atm. No degradation of the Meissner transition or other indications of inhomogeneity or phase segregation with doping are noted, suggesting that oxygen doped Bi_2Sr _2CaCu_2O _{8+delta} is a suitable system for pursuing doping studies. The decrease in T _{c} with concentration for 0.34 <=q n <=q 0.50 indicates that a high carrier concentration regime exists where T_{c} decreases with n and suggests that this decrease does not arise from material inhomogeneity or other materials problems. The physical properties of these Bi _2Sr_2CaCu _2O_{8+delta} crystals, in this high carrier concentration regime, will be discussed.

Endurance training and GH administration in elderly women

DEFF Research Database (Denmark)

Lange, K H; Lorentsen, J; Isaksson, F

2001-01-01

and after completion of the training program. Similarly, no effect on subcutaneous abdominal adipose tissue lipolysis was observed when combining endurance training with rhGH administration. However, in both the placebo and the GH groups, fat oxidation was significantly increased during exercise performed......In the present study, the effect of endurance training alone and endurance training combined with recombinant human growth hormone (rhGH) administration on subcutaneous abdominal adipose tissue lipolysis was investigated. Sixteen healthy women [age 75 +/- 2 yr (mean +/- SE)] underwent a 12-wk...... endurance training program on a cycle ergometer. rhGH was administered in a randomized, double-blinded, placebo-controlled design in addition to the training program. Subcutaneous abdominal adipose tissue lipolysis was estimated by means of microdialysis combined with measurements of subcutaneous abdominal...

Computer x-ray powder diffraction patterns and densities for corundum, aluminium, zirconium, delta-UZr2 and the zirconium hydrides

International Nuclear Information System (INIS)

Ferguson, I.F.

1976-11-01

The computer-calculated X-ray powder diffraction patterns and theoretical densities of α-Al 2 O 3 ; Al; α-Zr; β-Zr; delta-UZr 2 ; γ, delta - and epsilon-zirconium hydrides are presented. Brief comments are given on some of the published X-ray powder diffraction data on these phases. (author)

Improving chemical solution deposited YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} film properties via high heating rates

Energy Technology Data Exchange (ETDEWEB)

Siegal, M.P.; Dawley, J.T.; Clem, P.G.; Overmyer, D.L

2003-12-01

The superconducting and structural properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films grown from chemical solution deposited (CSD) metallofluoride-based precursors improve by using high heating rates to the desired growth temperature. This is due to avoiding the nucleation of undesirable a-axis grains at lower temperatures, from 650 to 800 deg. C in p(O{sub 2})=0.1%. Minimizing time spent in this range during the temperature ramp of the ex situ growth process depresses a-axis grain growth in favor of the desired c-axis orientation. Using optimized conditions, this results in high-quality YBCO films on LaAlO{sub 3}(1 0 0) with J{sub c}(77 K) {approx} 3 MA/cm{sup 2} for films thicknesses ranging from 60 to 140 nm. In particular, there is a dramatic decrease in a-axis grains in coated-conductors grown on CSD Nb-doped SrTiO{sub 3}(1 0 0) buffered Ni(1 0 0) tapes.

Surface structure of Bi2Sr2CaCu2O(8+delta) high-temperature superconductors studied using low-energy electron diffraction

Science.gov (United States)

Lindberg, P. A. P.; Shen, Z.-X.; Wells, B. O.; Mitzi, D. B.; Lindau, I.

1988-12-01

The surface structure of Bi2Sr2CaCu2O(8+delta) has been studied using low-energy electron diffraction (LEED). Sharp diffraction spots indicative of a well-ordered surface are observed. The LEED patterns unequivocally show that this type of material preferentially cleaves along the a-b planes of the nearly tetragonal unit cell. A superstructure extending along one of the axes in the a-b plane (b) is found to have a periodicity of 27 + or - 0.5 A, in good agreement with earlier studies of the three-dimensional crystal structure. The superstructure at the surface is nonlocal in character and reflects the long-range superlattice of the bulk along the b axis. Intensity modulations of the diffraction spots oriented along the b axis are also reported and discussed in terms of the cell dimension of the unit cell along the b axis.

Primary empty sella and GH deficiency: prevalence and clinical implications

Directory of Open Access Journals (Sweden)

Maurizio Poggi

2012-01-01

Full Text Available Primary empty sella (PES is a particular anatomical condition characterized by the herniation of liquor within the sella turcica. The pathogenesis of this alteration, frequently observed in general population, is not yet completely understood. Recently reports demonstrated, in these patients, that hormonal pituitary dysfunctions, specially growth hormone (GH/insulin-like growth factor (IGF-I axis ones, could be relevant. The aim of this paper is to evaluate GH/IGF-I axis in a group of adult patients affected by PES and to verify its clinical relevance. We studied a population of 28 patients with a diagnosis of PES. In each patient we performed a basal study of thyroid, adrenal and gonadal - pituitary axis and a dynamic evaluation of GH/IGF-I after GH-releasing hormone (GHRH plus arginine stimulation test. To evaluate the clinical significance of GH/IGF-I axis dysfunction we performed a metabolic and bone status evaluation in every patients. We found the presence of GH deficit in 11 patients (39.2 %. The group that displayed a GH/IGF-I axis dysfunction showed an impairment in metabolic profile and bone densitometry. This study confirms the necessity to screen the pituitary function in patients affected by PES and above all GH/IGF-I axis. Moreover the presence of GH deficiency could be clinically significant.

Kinetic study on ligand exchange reaction between ethylenedicysteine and 99mTc- glucoheptonate (99mTc-GH)

International Nuclear Information System (INIS)

Wu, C.Y.; Ji, S.R.; Lu, C.X.; Ding, S.Y.; Chen, Z.P.; Lin, X.T.

2002-01-01

Aim: 99m Tc-L,L-ethylenedicysteine( 99m Tc-EC)is a new type of renal imaging agent. It can be labeled very easily and efficiently at room temperature through direct labeling at pH 12. The need for direct labeling at pH 12 does not compromise the simplicity and ease of preparation of 99m Tc-EC and its practical usefulness in daily routine. On the basis of the labeling experiments, we developed a ligand exchange labeling method, in which the labeling EC with 99m Tc can be performed at pH 8. In order to provide a theoretic basis, a detailed kinetic study of ligand exchange reaction between 99m Tc- glucoheptonate( 99m Tc-GH) and EC was carried out. Materials and Methods: 99m Tc-EC is prepared as follows: 99m Tc-GH + EC → 99m Tc-EC + GH, labeling can be easily performed by adding 99m TcO 4 - (2∼6ml generator elute) to glucoheptonate solution containing SnCl 2 .2H 2 O solution to form 99m Tc-GH, then freshly prepared 99m Tc-GH is transferred to the aqueous solution of different concentrations of EC at different pH value, after being shaken, 99m Tc-EC was formed. Radiolabeling yield(RLY) and radiochemical purity(RCP) of 99m Tc-GH and 99m Tc-EC were measured by Xinhua No.1 paper with developing system of Me 2 CO/H 2 O/con.NH 3 .H 2 O=9/3/1(V/V). 99m Tc-GH(RCP must be over 98%, 80ul, 3.6∼7.4MBq) was added to 1ml of 0.5mol/L phosphate buffer(pH 12) containing different amount of EC(150, 75, 50 and 15ug), the sample was taken out at different time intervals and RCP was determined. The solution of EC(30ul, 5g/L) was added to 1ml of 0.5mol/L phosphate buffer at different pH value(pH11, 10, 9, 8, 7), after completely vortexed, 99m Tc-GH(RCP must be over 98%, 80ul, 3.6∼7.4MBq) was then added, the sample was taken out and RCP was determined as above. The rate constant(k) of ligand exchange reaction at different concentrations of EC and different reaction pH values were calculated out by integrating. Plot ln[1/(1-RLY)] vs t(time) showed a liner relationship, and the rate

Consolidation of powders of the superconductor YBa/sub 2/Cu/sub 3/O/sub 7-. delta. / by high energy-high rate processing

Energy Technology Data Exchange (ETDEWEB)

Lee, J.Y.; Persad, C.; Swinnea, J.S.; Marcus, H.L.; Steinfink, H. (Texas Univ., Austin, TX (USA). Center for Materials Science and Engineering)

1988-01-01

The consolidation response of powders of the superconducting compound YBa/sub 2/Cu/sub 3/O/sub 7-{delta}/ by itself and admixed with metal powders is reported. The processing approach relies on short duration (2/), pulse resistive heating of powders under applied pressures of 200 MPa to 400 MPa. Powders and fabricated disk concepts were characterized by X-ray diffraction, optical and scanning electron microscopy.

O2 uptake kinetics during exercise at peak O2 uptake.

Science.gov (United States)

Scheuermann, Barry W; Barstow, Thomas J

2003-11-01

Compared with moderate- and heavy-intensity exercise, the adjustment of O2 uptake (VO2) to exercise intensities that elicit peak VO2 has received relatively little attention. This study examined the VO2 response of 21 young, healthy subjects (25 +/- 6 yr; mean +/- SD) during cycle ergometer exercise to step transitions in work rate (WR) corresponding to 90, 100, and 110% of the peak WR achieved during a preliminary ramp protocol (15-30 W/min). Gas exchange was measured breath by breath and interpolated to 1-s values. VO2 kinetics were determined by use of a two- or three-component exponential model to isolate the time constant (tau2) as representative of VO2 kinetics and the amplitude (Amp) of the primary fast component independent of the appearance of any VO2 slow component. No difference in VO2 kinetics was observed between WRs (tau90 = 24.7 +/- 9.0; tau100 = 22.8 +/- 6.7; tau110 = 21.5 +/- 9.2 s, where subscripts denote percent of peak WR; P > 0.05); nor in a subgroup of eight subjects was tau2 different from the value for moderate-intensity (exercise (tau2 = 25 +/- 12 s, P > 0.05). As expected, the Amp increased with increasing WRs (Amp90 = 2,089 +/- 548; Amp100 = 2,165 +/- 517; Amp110 = 2,225 +/- 559 ml/min; Amp90 vs. Amp110, P exercise, the gain of the Vo2 response (as deltaVO2/DeltaWR) is reduced for exercise transitions in the severe-intensity domain, but the approach to this gain is well described by a common time constant that is invariant across work intensities. The lower deltaVO2/deltaWR may be due to an insufficient adjustment of the cardiovascular and/or pulmonary systems that determine O2 delivery to the exercising muscles or due to recruitment of motor units with lower oxidative capacity, after the onset of exercise in the severe-intensity domain.

The GH/IGF-1 axis in obesity: pathophysiology and therapeutic considerations.

Science.gov (United States)

Berryman, Darlene E; Glad, Camilla A M; List, Edward O; Johannsson, Gudmundur

2013-06-01

Obesity has become one of the most common medical problems in developed countries, and this disorder is associated with high incidences of hypertension, dyslipidaemia, cardiovascular disease, type 2 diabetes mellitus and specific cancers. Growth hormone (GH) stimulates the production of insulin-like growth factor 1 in most tissues, and together GH and insulin-like growth factor 1 exert powerful collective actions on fat, protein and glucose metabolism. Clinical trials assessing the effects of GH treatment in patients with obesity have shown consistent reductions in total adipose tissue mass, in particular abdominal and visceral adipose tissue depots. Moreover, studies in patients with abdominal obesity demonstrate a marked effect of GH therapy on body composition and on lipid and glucose homeostasis. Therefore, administration of recombinant human GH or activation of endogenous GH production has great potential to influence the onset and metabolic consequences of obesity. However, the clinical use of GH is not without controversy, given conflicting results regarding its effects on glucose metabolism. This Review provides an introduction to the role of GH in obesity and summarizes clinical and preclinical data that describe how GH can influence the obese state.

Effects of short-term glucocorticoid deprivation on growth hormone (GH) response to GH-releasing peptide-6: Studies in normal men and in patients with adrenal insufficiency

OpenAIRE

Pinto, Ana Claudia de Assis Rocha [UNIFESP; Dias-da-Silva, Magnus Régios [UNIFESP; Martins, Manoel R. [UNIFESP; Brunner, Elisa [UNIFESP; Lengyel, Ana Maria Judith [UNIFESP

2000-01-01

There are no data in the literature about the effects of glucocorticoid deprivation on GH-releasing peptide-g (GHRP-6)-induced GH release. the aims of this study were to evaluate GH responsiveness to GHRP-6 1) after metyrapone administration in normal men, and 2) in patients with chronic hypocortisolism after glucocorticoid withdrawal for 72 h. in normal subjects, metyrapone ingestion did not alter significantly GH responsiveness to GHRP-6 [n = 8; peak, 39.3 +/- 7.1 mu g/L; area under the cur...

GH Responsiveness to Combined GH-Releasing Hormone and Arginine Administration in Obese Patients with Fibromyalgia Syndrome.

Science.gov (United States)

Rigamonti, Antonello E; Grugni, Graziano; Arreghini, Marco; Capodaglio, Paolo; De Col, Alessandra; Agosti, Fiorenza; Sartorio, Alessandro

2017-01-01

Reportedly, fibromyalgia (FM) is frequently associated with reduced IGF-1 levels and GH hyporesponsiveness to different GH stimulation tests. Since there is a high prevalence of obesity in FM, and obesity itself is characterized by hyposomatotropism, the aim of this study was to assess IGF-1 levels and GH responsiveness in sixteen severely obese women suffering from FM, who, subdivided into two subgroups on the basis of their age-dependent IGF-1 values (> or BMI than that with normal IGF-1 SDS. GH peak and area under the curve were not correlated with CRP, ESR, or tender point score, while significant correlations were found with fat-free mass and fat mass. In conclusion, this study shows the existence of a high prevalence of GH-IGF-1 dysfunction in patients with both FM and obesity, presumably as a consequence of the obese rather than fibromyalgic condition.

Growth of epitaxial Ba2YCu3O(7-delta) thin films and control of their superconducting properties

International Nuclear Information System (INIS)

Siegal, M.P.; Phillips, J.M.

1992-01-01

The relationship is experimentally defined between the superconducting behavior of Ba2YCu3O(7-delta) (BYCO) films and their structural characteristics. The BYCO films are grown on LaAlO3 100-plane by coevaporating BaF2, Y, and Cu followed by ex situ annealing, and the crystalline quality is tested by Rutherford backscattering ion channeling. SEM is employed to study film morphology, and several techniques are used to measure the transition temperature (Tc), critical current density (Jc), and the penetration length. It is found that point defects and dislocations decrease as the high-temperature stage (Ta) increases; crevices, pinholes, and microcracks are also noted which are related to specific values of Tc, Ta, and penetration length. The results of the present experiments indicate that the material properties of superconducting materials should be examined closely to distinguish between pure superconducting behavior and characteristics related to material structure. 21 refs

GhCAX3 gene, a novel Ca(2+/H(+ exchanger from cotton, confers regulation of cold response and ABA induced signal transduction.

Directory of Open Access Journals (Sweden)

Lian Xu

Full Text Available As a second messenger, Ca(2+ plays a major role in cold induced transduction via stimulus-specific increases in [Ca(2+]cyt, which is called calcium signature. During this process, CAXs (Ca(2+/H(+ exchangers play critical role. For the first time, a putative Ca(2+/H(+ exchanger GhCAX3 gene from upland cotton (Gossypium hirsutum cv. 'YZ-1' was isolated and characterized. It was highly expressed in all tissues of cotton except roots and fibers. This gene may act as a regulator in cotton's response to abiotic stresses as it could be up-regulated by Ca(2+, NaCl, ABA and cold stress. Similar to other CAXs, it was proved that GhCAX3 also had Ca(2+ transport activity and the N-terminal regulatory region (NRR through yeast complementation assay. Over-expression of GhCAX3 in tobacco showed less sensitivity to ABA during seed germination and seedling stages, and the phenotypic difference between wild type (WT and transgenic plants was more significant when the NRR was truncated. Furthermore, GhCAX3 conferred cold tolerance in yeast as well as in tobacco seedlings based on physiological and molecular studies. However, transgenic plant seeds showed more sensitivity to cold stress compared to WT during seed germination, especially when expressed in N-terminal truncated version. Finally, the extent of sensitivity in transgenic lines was more severe than that in WT line under sodium tungstate treatment (an ABA repressor, indicating that ABA could alleviate cold sensitivity of GhCAX3 seeds, especially in short of its NRR. Meanwhile, we also found that overexpression of GhCAX3 could enhance some cold and ABA responsive marker genes. Taken together, these results suggested that GhCAX3 plays important roles in the cross-talk of ABA and cold signal transduction, and compared to full-length of GhCAX3, the absence of NRR could enhance the tolerance or sensitivity to cold stress, depending on seedling's developmental stages.

Daily variations of delta 18O and delta D in daily samplings of air water vapour and rain water in the Amazon Basin

International Nuclear Information System (INIS)

Matsui, E.; Salati, E.; Ribeiro, M.N.G.; Tancredi, A.C.F.N.S.; Reis, C.M. dos

1984-01-01

The movement of rain water in the soil from 0 to 120 cm depth using delta 18 O weekly variations is studied. A study of the delta D variability in water vapour and rain water samples during precipitation was also done, the samples being collected a 3 minute intervals from the beginning to the end of precipitation. (M.A.C.) [pt

Simple, accurate equations for human blood O2 dissociation computations.

Science.gov (United States)

Severinghaus, J W

1979-03-01

Hill's equation can be slightly modified to fit the standard human blood O2 dissociation curve to within plus or minus 0.0055 fractional saturation (S) from O less than S less than 1. Other modifications of Hill's equation may be used to compute Po2 (Torr) from S (Eq. 2), and the temperature coefficient of Po2 (Eq. 3). Variations of the Bohr coefficient with Po2 are given by Eq. 4. S = (((Po2(3) + 150 Po2)(-1) x 23,400) + 1)(-1) (1) In Po2 = 0.385 In (S-1 - 1)(-1) + 3.32 - (72 S)(-1) - 0.17(S6) (2) DELTA In Po2/delta T = 0.058 ((0.243 X Po2/100)(3.88) + 1)(-1) + 0.013 (3) delta In Po2/delta pH = (Po2/26.6)(0.184) - 2.2 (4) Procedures are described to determine Po2 and S of blood iteratively after extraction or addition of a defined amount of O2 and to compute P50 of blood from a single sample after measuring Po2, pH, and S.

Correction of mass spectrometric isotope ratio measurements for isobaric isotopologues of O2, CO, CO2, N2O and SO2.

Science.gov (United States)

Kaiser, Jan; Röckmann, Thomas

2008-12-01

Gas isotope ratio mass spectrometers usually measure ion current ratios of molecules, not atoms. Often several isotopologues contribute to an ion current at a particular mass-to-charge ratio (m/z). Therefore, corrections have to be applied to derive the desired isotope ratios. These corrections are usually formulated in terms of isotope ratios (R), but this does not reflect the practice of measuring the ion current ratios of the sample relative to those of a reference material. Correspondingly, the relative ion current ratio differences (expressed as delta values) are first converted into isotopologue ratios, then into isotope ratios and finally back into elemental delta values. Here, we present a reformulation of this data reduction procedure entirely in terms of delta values and the 'absolute' isotope ratios of the reference material. This also shows that not the absolute isotope ratios of the reference material themselves, but only product and ratio combinations of them, are required for the data reduction. These combinations can be and, for carbon and oxygen have been, measured by conventional isotope ratio mass spectrometers. The frequently implied use of absolute isotope ratios measured by specially calibrated instruments is actually unnecessary. Following related work on CO2, we here derive data reduction equations for the species O2, CO, N2O and SO2. We also suggest experiments to measure the required absolute ratio combinations for N2O, SO2 and O2. As a prelude, we summarise historic and recent measurements of absolute isotope ratios in international isotope reference materials. Copyright 2008 John Wiley & Sons, Ltd.

Concentration effect of Tm3+ on cathodoluminescence properties of SiO2: Tm3+ and SiO2:Ho3+, Tm3+ systems

CSIR Research Space (South Africa)

Dhlamini, MS

2012-05-01

Full Text Available .physb.2011.09.091 Concentration effect of Tm3+ on cathodoluminescence properties of SiO2: Tm 3+ and SiO2:Ho 3+, Tm3+ systems M.S. Dhlamini, G.H. Mhlongo, H.C. Swart, O.M. Ntwaeaborwa, K.T. Hillie ABSTRACT: Cathodoluminescence (CL) properties of Si...O2 powders activated with thulium (Tm3+) and holmium (Ho3+) ions prepared by a sol–gel process were investigated. Different molar concentrations of Tm3+ co-doped with Ho3+ were studied. The 460 nm peak was monitored and the influence of the beam...

Selective Rutherford backscattering techniques in the study of transition-metal implanted YBa{sub 2}C{sub 3}O{sub 7-{delta}}

Energy Technology Data Exchange (ETDEWEB)

Martin, J.W.; Russell, G.J. [New South Wales Univ., Kensington, NSW (Australia). School of Physics; Cohen, D.D.; Evans, P.J. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

1993-12-31

Using a metal-vapor vacuum arc ion source, several as-grown, large single crystal YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} were implanted with a dose of 1x10{sup 17} zinc, nickel and iron ions. After implantation the crystal was subjected to two anneal cycles that has allowed to examine crystal structure, superconducting transitions and composition, through X-ray diffraction, rutherford backscattering spectroscopy (RBS) and AC susceptibility measurements respectively. Although RBS discriminates strongly against light elements, such as oxygen, the use of resonant reaction {sup 16}O ({alpha}, {alpha}){sup 16}O at 3.4 MeV was beneficial, as its cross section is nearly 23 times that of the rutherford cross section. 4 figs.

Selective Rutherford backscattering techniques in the study of transition-metal implanted YBa{sub 2}C{sub 3}O{sub 7-{delta}}

Energy Technology Data Exchange (ETDEWEB)

Martin, J W; Russell, G J [New South Wales Univ., Kensington, NSW (Australia). School of Physics; Cohen, D D; Evans, P J [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

1994-12-31

Using a metal-vapor vacuum arc ion source, several as-grown, large single crystal YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} were implanted with a dose of 1x10{sup 17} zinc, nickel and iron ions. After implantation the crystal was subjected to two anneal cycles that has allowed to examine crystal structure, superconducting transitions and composition, through X-ray diffraction, rutherford backscattering spectroscopy (RBS) and AC susceptibility measurements respectively. Although RBS discriminates strongly against light elements, such as oxygen, the use of resonant reaction {sup 16}O ({alpha}, {alpha}){sup 16}O at 3.4 MeV was beneficial, as its cross section is nearly 23 times that of the rutherford cross section. 4 figs.

The oxygen-isotope effect on the in-plane penetration depth in underdoped Y{sub 1-x} Pr{sub x} Ba{sub 2} Cu{sub 3} O{sub 7-{delta}} as revealed by muon-spin rotation

Energy Technology Data Exchange (ETDEWEB)

Khasanov, R [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland); Shengelaya, A [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland); Conder, K [Laboratory for Neutron Scattering, ETH Zuerich and PSI Villigen, CH-5232 Villigen PSI (Switzerland); Morenzoni, E [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Savic, I M [Faculty of Physics, University of Belgrade, 11001 Belgrade (Yugoslavia); Keller, H [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland)

2003-01-22

The oxygen-isotope ({sup 16}O/{sup 18}O) effect (OIE) on the in-plane penetration depth {lambda}{sub ab} (0) in underdoped Y{sub 1-x} Pr{sub x} Ba{sub 2} Cu{sub 3} O{sub 7-{delta}} was studied by means of muon-spin rotation. A pronounced OIE on {lambda}{sub ab}{sup -2} (0) was observed with a relative isotope shift of {delta}{lambda}{sub ab}{sup -2} /{lambda} {sub ab}{sup -2} = -5(2)% for x=0.3 and -9(2)% for x=0.4. The OIE exponents of T{sub c} and of {lambda}{sub ab}{sup -2} (0) exhibit a relation that appears to be generic for cuprate superconductors. (letter to the editor)

Mean proloculus size, delta super(13) C and delta super(18) O variations in recent benthic foraminifera from the west coast of India and their climatic implications

Digital Repository Service at National Institute of Oceanography (India)

Nigam, R.; Sarkar, A.

The interrelationship between mean proloculus size (MPS), delta super(18) O and delta super(13) C vatiations in benthic foraminiferal species Rotalidium annectens and their relation with temperature (T) and salinity (S) have been studied in samples...

Crystallization and characterization of Y2O3-SiO2 glasses

Science.gov (United States)

Drummond, Charles H., III; Lee, William E.; Sanders, W. A.; Kiser, J. D.

1991-01-01

Glasses in the yttria-silica system with 20 to 40 mol pct Y2O3 were subjected to recrystallization studies after melting at 1900 to 2100 C in W crucibles in 1 and 50 atm N2. The TEM and XRD results obtained indicate the presence of the delta, gamma, gamma prime, and beta-Y2Si2O7 crystalline phases, depending on melting and quenching conditions. Heat treatment in air at 1100 to 1600 C increased the amount of crystallization, and led to the formation of Y2SiO5, cristabalite, and polymorphs of Y2Si2O7. Also investigated were the effects of 5 and 10 wt pct zirconia additions.

Growth hormone (GH) activity is associated with increased serum oestradiol and reduced Anti-Müllerian Hormone in healthy male volunteers treated with GH and a GH antagonist

DEFF Research Database (Denmark)

Andreassen, M; Frystyk, Jan; Faber, J

2013-01-01

Growth hormone (GH) and insulin-like growth factor I (IGF-I) receptors are present on pituitary gonadotrophs and on testicular Leydig and Sertoli cells. Thus, the GH/IGF-I system may modulate the pituitary-gonadal axis in males. This is a randomized cross-over study. Eight healthy male volunteers...... (160-290) vs. 106 (97-157) μg/L, p = 0.001) and oestradiol (86 ± 28 vs. 79 ± 25 pm, p = 0.060) decreased. No significant changes or trends in the other reproductive hormones occurred during the two treatment regimens. GH/IGF-I activity was positively associated with serum oestradiol, suggesting that GH...

Growth hormone-promoted tyrosyl phosphorylation of SHC proteins and SHC association with Grb2

DEFF Research Database (Denmark)

VanderKuur, J; Allevato, G; Billestrup, Nils

1995-01-01

. To gain insight into pathways coupling GH receptor (GHR) to MAP kinase activation and signaling molecules that might interact with GHR and its associated tyrosine kinase JAK2, we examined whether SHC and Grb2 proteins serve as signaling molecules for GH. Human GH was shown to promote the rapid tyrosyl...... phosphorylation of 66-, 52-, and 46-kDa SHC proteins in 3T3-F442A fibroblasts. GH also promoted binding of GHR and JAK2 to the SH2 domain of 46/52-kDa SHC protein fused to glutathione S-transferase (GST). Constitutively phosphorylated JAK2, from COS-7 cells transiently transfected with murine JAK2 cDNA, bound......-638 and GHR1-638(Y333,338F), GH stimulated phosphorylation of all 3 SHC proteins whereas GH stimulated phosphorylation of only the 66- and 52-kDa SHC proteins in cells expressing GHR1-454. GH had no effect on SHC phosphorylation in cells expressing GHR1-294 or GHR delta P, the latter lacking amino acids 297...

Controlling the Electronic Properties in La1/3Sr 2/3FeO3-delta Complex Perovskite Oxides

Science.gov (United States)

Krick, Alex L.

the temperature-dependent resistivity. Carrier behavior within the superlattices was also explored by fitting the temperature dependent resistivity to common conduction models. The conduction mechanism fits show that the transport at high temperatures is dominated by weakly insulating behavior due to small polaron conduction and at low temperatures the resistivity can be fit to both a novel power law and 3-dimensional variable range hopping. Additionally, reversible changes of the structural and electronic transport properties of La1/3Sr2/3FeO3-delta/Gd-doped CeO2 (GDC) heterostructures arising from the manipulation of delta are presented. Thermally induced oxygen loss leads to a c-axis lattice expansion and an increase in resistivity in an LSFO film capped with GDC. In a three-terminal device where a gate bias is applied across the GDC layer to alter the LSFO oxygen stoichiometry, the ferrite channel is shown to undergo an order of magnitude change in resistance using gate voltages of less than 1 V applied at 500 K. The changes in resistance remain upon cooling to room temperature, in the absence of a gate bias, suggesting solid state ionic gating of perovskite oxides as a promising platform for applications in non-volatile, multistate devices. Along with the experiments of controlling delta in a device format, the kinetics of oxygen loss as a function of biaxial strain was investigated.

Barbados Oxygen Isotope Data (delta 18O) for the Late Pleistocene

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Coral-based delta18O time-series derived from measurements made on submerged or drowned coral reef sequence. The core samples used have been described elsewhere (cf....

Formation of Y{sub x}Nd{sub 1-x}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} (0{<=}x{<=}0.9) superconductors from an undercooled melt via aero-acoustic levitation

Energy Technology Data Exchange (ETDEWEB)

Gustafson, D.E.; Hofmeister, W.H.; Bayuzick, R.J.; Nagashio, K.; Kuribayashi, K

2003-01-20

This paper presents the results of rapid solidification experiments performed on the copper oxide superconductors Y{sub x}Nd{sub 1-x}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} (0{<=}x{<=}0.9). Spherical rare earth (RE) 123 specimens were levitated in O{sub 2} using aero-acoustic levitation (AAL), melted with a laser, undercooled, and solidified. The peritectic transformation temperature for the reaction RE{sub 2}BaCuO{sub 5}+liquid{yields}REBa{sub 2}Cu{sub 3}O{sub 7-{delta}} corresponding to the maximum recalescence temperature during solidification was determined. RE123 was formed directly from the melt for Y-Nd binary alloy compositions with Nd concentration greater than 20% (Y concentration less than 80%). A minimum in the peritectic transformation temperature for the Nd/Y123 system corresponding to a composition Y{sub 0.3}Nd{sub 0.7}123 was determined at 66 deg. C below the peritectic of pure Nd123.

Respiratory depression after intravenous administration of delta-selective opioid peptide analogs.

Science.gov (United States)

Szeto, H H; Soong, Y; Wu, D; Olariu, N; Kett, A; Kim, H; Clapp, J F

1999-01-01

We compared the effects of three micro-(DAMGO, DALDA, TNPO) and three delta-(DPDPE, DELT, SNC-80) opioid agonists on arterial blood gas after IV administration in awake sheep. None of the mu agonists altered pO2, pCO2 or pH. All three mu agonists decreased pO2 increased pCO2 and decreased pO2, and this effect was not sensitive to naloxone or TIPPpsi, a delta-antagonist, suggesting that it is not mediated by beta-opioid receptors. When administered to pregnant animals, there were significant changes in fetal pCO2 and pH. It may be possible to develop delta-selective opioid agonists which do not produce respiratory depression.

Latest paleocene benthic extinction event on the southern tethyan shelf (Egypt): Foraminiferal stable isotopic (delta C-13,delta O-18) records

OpenAIRE

Schmitz, B; Speijer, Robert; Aubry, MP

1996-01-01

The dramatic global extinction of 35%-50% of benthic foraminifera species in the deep sea in the latest Paleocene and associated negative excursions in delta(13)C and delta(18)O may be related to spreading of warm, saline bottom water from subtropical Tethyan shallow regions over the sea floor worldwide, Our study of neritic sections in Egypt shows that in the southern shallow Tethys, a prominent long-term change in bottom-water chemistry, sedimentation, and benthic foraminifera fauna was ini...

Correlation between GH and IGF-1 during treatment for acromegaly.

Science.gov (United States)

Oldfield, Edward H; Jane, John A; Thorner, Michael O; Pledger, Carrie L; Sheehan, Jason P; Vance, Mary Lee

2017-06-01

OBJECTIVE The relationship between growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in patients with acromegaly as serial levels drop over time after treatment has not been examined previously. Knowledge of this relationship is important to correlate pretreatment levels that best predict response to treatment. To examine the correlation between GH and IGF-1 and IGF-1 z-scores over a wide range of GH levels, the authors examined serial GH and IGF-1 levels at intervals before and after surgery and radiosurgery for acromegaly. METHODS This retrospective analysis correlates 414 pairs of GH and IGF-1 values in 93 patients with acromegaly. RESULTS Absolute IGF-1 levels increase linearly with GH levels only up to a GH of 4 ng/ml, and with IGF-1 z-scores only to a GH level of 1 ng/ml. Between GH levels of 1 and 10 ng/ml, increases in IGF-1 z-scores relative to changes in GH diminish and then plateau at GH concentrations of about 10 ng/ml. From patient to patient there is a wide range of threshold GH levels beyond which IGF-1 increases are no longer linear, GH levels at which the IGF-1 response plateaus, IGF-1 levels at similar GH values after the IGF-1 response plateaus, and of IGF-1 levels at similar GH levels. CONCLUSIONS In acromegaly, although IGF-1 levels represent a combination of the integrated effects of GH secretion and GH action, the tumor produces GH, not IGF-1. Nonlinearity between GH and IGF-1 occurs at GH levels far below those previously recognized. To monitor tumor activity and tumor viability requires measurement of GH levels.

Tunneling spectroscopy of heavily underdoped crystals of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}

Energy Technology Data Exchange (ETDEWEB)

Ozyuzer, L.; Zasadzinski, J. F.; Miyakawa, N.; Kendziora, C.; Jian, S.; Hinks, D. G.; Gray, K. E.

2000-02-17

Crystals of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} with optimal {Tc} = 95 K have been underdoped using two different methods and the superconducting gaps have been obtained by tunneling. In some cases, three different tunneling geometries have been utilized: point contact, STM and break junctions. The first doping method involves control of the oxygen content by annealing in various partial pressures of oxygen. These crystals exhibit a narrow spread of gap values over a wide doping range from overdoped ({Tc} = 56 K) to underdoped with {Tc} = 70 K. However, for underdoped crystals with {Tc} midpoints in the range 25 K--63 K, there is a dramatic increase in the spread of gap values which may signal the development of static phase separation of either chemical or electronic origin. To avoid possible chemical phase separation, the authors have explored another doping procedure which incorporates Dy substitution on the Ca site. These crystals exhibit a relatively narrow superconducting transition width and some preliminary tunneling spectra will be presented.

Electronic parameters of Sr2Nb2O7 and chemical bonding

DEFF Research Database (Denmark)

Atuchin, V.V.; Grivel, Jean-Claude; Korotkov, A.S.

2008-01-01

/2)) and Delta(O-Sr) = BE(O 1s)-BE(Sr 3d(5/2)), were used to characterize the valence electron transfer on the formation of the Nb-O and Sr-O bonds. The chemical bonding effects were considered on the basis of our XPS results for Sr2Nb2O7 and earlier published structural and XPS data for other Sr- or Nb...

Multipathway modulation of exercise and glucose stress effects upon GH secretion in healthy men.

Science.gov (United States)

Veldhuis, Johannes D; Olson, Thomas P; Takahashi, Paul Y; Miles, John M; Joyner, Michael J; Yang, Rebecca J; Wigham, Jean

2015-09-01

Exercise evokes pulsatile GH release followed by autonegative feedback, whereas glucose suppresses GH release followed by rebound-like GH release (feedforward escape). Here we test the hypothesis that age, sex steroids, insulin, body composition and physical power jointly determine these dynamic GH responses. This was a prospectively randomized glucose-blinded study conducted in the Mayo Center for Advancing Translational Sciences in healthy men ages 19-77 years (N=23). Three conditions, fasting/rest/saline, fasting/exercise/saline and fasting/rest/iv glucose infusions, were used to drive GH dynamics during 10-min blood sampling for 6h. Linear correlation analysis was applied to relate peak/nadir GH dynamics to age, sex steroids, insulin, CT-estimated abdominal fat and physical power (work per unit time). Compared with the fasting/rest/saline (control) day, fasting/exercise/saline infusion evoked peak GH within 1h, followed by negative feedback 3-5h later. The dynamic GH excursion was strongly (R(2)=0.634) influenced by (i) insulin negatively (P=0.011), (ii) power positively (P=0.0008), and (iii) E2 positively (P=0.001). Dynamic glucose-modulated GH release was determined by insulin negatively (P=0.0039) and power positively (P=0.0034) (R(2)=0.454). Under rest/saline, power (P=0.031) and total abdominal fat (P=0.012) (R(2)=0.267) were the dominant correlates of GH excursions. In healthy men, dynamic GH perturbations induced by exercise and glucose are strongly related to physical power, insulin, estradiol, and body composition, thus suggesting a network of regulatory pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

Correlation of tunneling spectra with surface nano-morphology and doping in thin YBa2Cu3O7-delta films

OpenAIRE

Sharoni, A.; Koren, G.; Millo, O.

2001-01-01

Tunneling spectra measured on thin epitaxial YBa2Cu3O7-delta films are found to exhibit strong spatial variations, showing U and V-shaped gaps as well as zero bias conductance peaks typical of a d-wave superconductor. A full correspondence is found between the tunneling spectra and the surface morphology down to a level of a unit-cell step. Splitting of the zero bias conductance peak is seen in optimally-doped and overdoped films, but not in the underdoped ones, suggesting that there is no tr...

Overall and cause-specific mortality in GH-deficient adults on GH replacement

DEFF Research Database (Denmark)

Gaillard, Rolf C; Mattsson, Anders F; Akerblad, Ann-Charlotte

2012-01-01

Hypopituitarism is associated with an increased mortality rate but the reasons underlying this have not been fully elucidated. The purpose of this study was to evaluate mortality and associated factors within a large GH-replaced population of hypopituitary patients.......Hypopituitarism is associated with an increased mortality rate but the reasons underlying this have not been fully elucidated. The purpose of this study was to evaluate mortality and associated factors within a large GH-replaced population of hypopituitary patients....

Differential effects of hGH and IGF-I on body proportions.

Science.gov (United States)

Laron, Zvi; Silbergeld, Aviva; Kauli, Rivka

2012-07-01

The differential growth effects of hGH and IGF-I on the upper/lower (U/L) body segment in relation to height (Ht) were analyzed in 15 patients with isolated Growth hormone deficiency (IGHD,:7M, 8F) mean age 5.0 +/- 3.2 (SD) years treated with hGH; 21 patients with multiple pituitary hormone deficiency including growth hormone (MPHD: 14M, 7F) aged 10.0 +/- 3.8, treated with hGH; 9 patients with Laron Syndrome (LS) (4M,5F) aged 6.9 +/- 5.6 years treated with IGF-I; 9 boys with intrauterine growth retardation (IUGR) aged 6.3 +/- 1.25 years treated by hGH; and 22 boys with idiopathic short stature (ISS) aged 8.0 +/- 1.55 years treated by hGH. The dose of hGH was 33 microg/kg/day, that of IGF-I 180-200 microg/kg/day. the U/L body segment ratio in IGHD patients decreased from 2.3 +/- 0.7 to 1.1 +/- 0.7 (p <0.001), and the Ht SDS increased from -4.9 +/- 1.3 to 2.3 +/- 1 (p < 0.001) following treatment. In MPHD patients the U/L body segment decreased from 1.1 +/- 1.1 to -0.6 +/- 1.0 (p < 0.001), and the Ht SDS increased from -3.3 +/- 1.4 to -2.5 +/- 1.0 (p < 0.009). In the LS group the U/L body segment ratio did not change with IGF-I treatment but Ht improved from -6.1 +/- 1.3 to -4.6 +/- 1.2 (p < 0.001), The differential growth response of the children with IUGR and with ISS resembled that of the children with LS. hGH and IGF-I act differentially on the spine and limbs.

Effect of rare-earth ion size on local electron structure in RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (R = Tm, Dy, Gd, Eu, Nd and Y) superconductors: A positron study

Energy Technology Data Exchange (ETDEWEB)

Chen Zhenping [Department of Technology and Physics, Zhengzhou University of Light Industry, 5 Dongfeng Road, Zhengzhou, Henan 450002 (China)]. E-mail: czhping@zzuli.edu.cn; Zhang Jincang [Department of Physics, Shanghai University, Shanghai 200436 (China); Su Yuling [Department of Technology and Physics, Zhengzhou University of Light Industry, 5 Dongfeng Road, Zhengzhou, Henan 450002 (China); Xue Yuncai [Department of Technology and Physics, Zhengzhou University of Light Industry, 5 Dongfeng Road, Zhengzhou, Henan 450002 (China); Cao Shixun [Department of Physics, Shanghai University, Shanghai 200436 (China)

2006-02-15

The effects of rare-earth ionic size on the local electron structure, lattice parameters and superconductivity have been investigated by positron annihilation technique (PAT) and related experiments for RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (R = Tm, Dy, Gd, Eu, Nd and Y) superconductors. The local electron density n {sub e} is evaluated as a function of the rare-earth radius. The results show that both the bulk-lifetime {tau} {sub B} and the defect lifetime {tau} {sub 2} increase with increasing rare-earth ionic radius, while the local electron density n {sub e} decrease with increasing rare-earth ionic radius. These results prove that the changes of n {sub e}, the degree of orthorhombic distortion and the coupling between the Cu-O chains and the CuO{sub 2} planes all have an effect on the superconductivity of RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} systems.

GdBa{sub 0.5}Sr{sub 0.5}Co{sub 2}O{sub 5+{delta}} layered perovskite as promising cathode for proton conducting solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Ding, Hanping [Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208 (United States); Xue, Xingjian, E-mail: Xue@cec.sc.ed [Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

2010-04-30

BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY7) exhibits adequate proton conductivity as well as sufficient chemical and thermal stability over a wide range of SOFC operating conditions, while layered GdBa{sub 0.5}Sr{sub 0.5}Co{sub 2}O{sub 5+{delta}} (GBSC) perovskite deposited on a doped ceria electrolyte demonstrates advanced electrochemical properties. This research fully takes advantage of these advanced properties and develops novel protonic ceramic membrane fuel cells (PCMFCs) of Ni-BZCY7|BZCY7|GBSC. The results show that the open-circuit potential of 1.003 V, maximum power density of 430 mW cm{sup -2}, and a low polarization resistance of the electrodes of 0.08 {Omega} cm{sup 2} are achieved at 700 {sup o}C. With temperature increases, the total cell resistance decreases, among which electrolyte resistance becomes increasingly dominant over polarization resistance. The results also indicate that GBSC perovskite cathode is a good candidate for intermediate temperature PCMFC development, while the developed Ni-BZCY7|BZCY7|GBSC cell is a promising functional material system for next generation SOFCs.

Inter- and intraplane softening of the vortex structure in Bi sub 2. 1Sr sub 1. 9Ca sub 0. 9Cu sub 2 O sub 8+. delta. :

Energy Technology Data Exchange (ETDEWEB)

Yazyi, J O; Arribere, A A; Duran, C; Cruz, F de la [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche; Mitzi, D B; Kapitulnik, A [Stanford Univ., CA (USA)

1991-01-01

High Q mechanical oscillator and ac susceptibility techniques have been used to study vortex dynamics in high quality single crystals of Bi{sub 2}.1Sr{sub 1}.9Ca{sub 0}.9Cu{sub 2}O{sub 8+{delta}} over a wide range of magnetic fields and different relative orientations between the magnetic field and the crystalline c axis. Our results confirm the existence of two transitions in the vortex response. It is shown that the transition at lower temperatures is associated to currents flowing across the CuO planes and the other one to currents in the planes. This means that the reversible region of the phase diagram is reached in two steps when increasing temperature. (Author).

Proton conducting solid oxide fuel cells with layered PrBa{sub 0.5}Sr{sub 0.5}Co{sub 2}O{sub 5+{delta}} perovskite cathode

Energy Technology Data Exchange (ETDEWEB)

Ding, Hanping; Xue, Xingjian [Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

2010-03-15

BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY7) exhibits adequate protonic conductivity as well as sufficient chemical and thermal stability over a wide range of SOFC operating conditions, while layered perovskite PrBa{sub 0.5}Sr{sub 0.5}Co{sub 2}O{sub 5+{delta}} (PBSC) has advanced electrochemical properties. This research fully takes advantage of these advanced properties and develops a novel protonic ceramic membrane fuel cell (PCMFC) of Ni-BZCY7 vertical stroke BZCY7 vertical stroke PBSC. Experimental results show that the cell may achieve the open-circuit potential of 1.005 V, the maximal power density of 520 mW cm{sup -2}, and a low electrode polarization resistance of 0.12 {omega}cm{sup 2} at 700 C. Increasing operating temperature leads to the decrease of total cell resistance, among which electrolyte resistance becomes increasingly dominant over polarization resistance. The results also indicate that PBSC perovskite cathode is a good candidate for intermediate temperature PCMFC development, while the developed Ni-BZCY7 vertical stroke BZCY7 vertical stroke PBSC cell is a promising functional material system for SOFCs. (author)

Effect of GH/IGF-1 on Bone Metabolism and Osteoporsosis

Directory of Open Access Journals (Sweden)

Vittorio Locatelli

2014-01-01

Full Text Available Background. Growth hormone (GH and insulin-like growth factor (IGF-1 are fundamental in skeletal growth during puberty and bone health throughout life. GH increases tissue formation by acting directly and indirectly on target cells; IGF-1 is a critical mediator of bone growth. Clinical studies reporting the use of GH and IGF-1 in osteoporosis and fracture healing are outlined. Methods. A Pubmed search revealed 39 clinical studies reporting the effects of GH and IGF-1 administration on bone metabolism in osteopenic and osteoporotic human subjects and on bone healing in operated patients with normal GH secretion. Eighteen clinical studies considered the effect with GH treatment, fourteen studies reported the clinical effects with IGF-1 administration, and seven related to the GH/IGF-1 effect on bone healing. Results. Both GH and IGF-1 administration significantly increased bone resorption and bone formation in the most studies. GH/IGF-1 administration in patients with hip or tibial fractures resulted in increased bone healing, rapid clinical improvements. Some conflicting results were evidenced. Conclusions. GH and IGF-1 therapy has a significant anabolic effect. GH administration for the treatment of osteoporosis and bone fractures may greatly improve clinical outcome. GH interacts with sex steroids in the anabolic process. GH resistance process is considered.

Effect of GH/IGF-1 on Bone Metabolism and Osteoporsosis

Science.gov (United States)

Locatelli, Vittorio; Bianchi, Vittorio E.

2014-01-01

Background. Growth hormone (GH) and insulin-like growth factor (IGF-1) are fundamental in skeletal growth during puberty and bone health throughout life. GH increases tissue formation by acting directly and indirectly on target cells; IGF-1 is a critical mediator of bone growth. Clinical studies reporting the use of GH and IGF-1 in osteoporosis and fracture healing are outlined. Methods. A Pubmed search revealed 39 clinical studies reporting the effects of GH and IGF-1 administration on bone metabolism in osteopenic and osteoporotic human subjects and on bone healing in operated patients with normal GH secretion. Eighteen clinical studies considered the effect with GH treatment, fourteen studies reported the clinical effects with IGF-1 administration, and seven related to the GH/IGF-1 effect on bone healing. Results. Both GH and IGF-1 administration significantly increased bone resorption and bone formation in the most studies. GH/IGF-1 administration in patients with hip or tibial fractures resulted in increased bone healing, rapid clinical improvements. Some conflicting results were evidenced. Conclusions. GH and IGF-1 therapy has a significant anabolic effect. GH administration for the treatment of osteoporosis and bone fractures may greatly improve clinical outcome. GH interacts with sex steroids in the anabolic process. GH resistance process is considered. PMID:25147565

Carrier compensation mechanism in heavily Nb-doped anatase Ti{sub 1-x}Nb{sub x}O{sub 2+{delta}} epitaxial thin films

Energy Technology Data Exchange (ETDEWEB)

Nogawa, H; Chikamatsu, A; Hirose, Y; Hasegawa, T [Department of Chemistry, University of Tokyo, Tokyo 113-0033 (Japan); Nakao, S [Kanagawa Academy of Science and Technology (KAST), Kawasaki 213-0012 (Japan); Kumigashira, H; Oshima, M, E-mail: chikamatsu@chem.s.u-tokyo.ac.jp [Department of Applied Chemistry, University of Tokyo, Tokyo 113-8656 (Japan)

2011-09-14

We investigated the electronic structures of anatase Ti{sub 1-x}Nb{sub x}O{sub 2+{delta}} (TNO) thin films as a function of Nb concentration x using photoemission spectroscopy (PES) measurements to elucidate the origin of the abrupt decrease in carrier activation in heavily Nb-doped regime. The existing intensity ratio of Nb{sup 5+} evaluated from Nb 3d core-level PES spectra maintained a constant value of {approx}0.8 at x = 0.06-0.3, implying that electron carriers generated by Nb doping are compensated by p-type defects. Ti 2p-3d and O1s-2p resonant PES measurements of x = 0.06-0.3 films revealed that the in-gap states positioned {approx}1 eV below the Fermi level (E{sub F}) have a mixed character of Ti 3d and O 2p orbitals, whereas the states at E{sub F} mainly have a Ti 3d nature. We proposed a carrier compensation mechanism that interstitial oxygen atoms strongly combined with surrounding Nb atoms kill conduction electrons in heavily Nb-doped anatase TiO{sub 2}.

Participação da via alfa-2 adrenérgica no controle da secreção do hormônio do crescimento no período pré-púbere em novilhas da raça Nelore: adrenergic in the control of growth hormone secretion in the pre-puberty period of the Nellore heifers

Directory of Open Access Journals (Sweden)

Emiliana de Oliveira Santana Batista

2011-08-01

Full Text Available O objetivo deste trabalho foi investigar a variação na secreção de GH em resposta ao tratamento com clonidina, agonista alfa-2 adrenérgico, no período pré-púbere de novilhas da raça Nelore, e desta forma obter informações neuroendócrinas envolvidas no processo de maturação sexual destes animais. A administração de clonidina (10 µg/kg, I.V., amostras 15 min por 4h foi feita nas novilhas aos oito (n =4, 12(n = 5 e 15 meses de idade (n = 4. A concentração de GH foi quantificada por radioimunoensaio (sensibilidade = 0,25 ng/mL, CV = 16%. Aos oito meses, a administração do estimulador alfa-2 adrenérgico aumentou a concentração de GH, área total de picos, área total de secreção de GH e amplitude do maior pico e reduziu o tempo para aparecimento de pico (P < 0,05. A administração de clonidina aumentou a concentração de GH aos 15 meses, e aos 12 meses, em intervalos restritos (P < 0,05. O uso da clonidina estimulou a secreção de GH em novilhas Nelore pré-púberes. Este efeito foi mais evidente nas novilhas aos oito meses, comparado aos 12 e 15 meses de idade.

Increased serum and bone matrix levels of transforming growth factor {beta}1 in patients with GH deficiency in response to GH treatment

DEFF Research Database (Denmark)

Ueland, Thor; Lekva, Tove; Otterdal, Kari

2011-01-01

Patients with adult onset GH deficiency (aoGHD) have secondary osteoporosis, which is reversed by long-term GH substitution. Transforming growth factor β1 (TGFβ1 or TGFB1) is abundant in bone tissue and could mediate some effects of GH/IGFs on bone. We investigated its regulation by GH/IGF1 in vivo...

Enhanced vortex pinning and critical current density in proton-irradiated YBa2Cu3O(7-delta) thin films

Science.gov (United States)

Venturini, E. L.; Siegal, M. P.; White, A. E.; Hou, S. Y.; Phillips, J. M.

1992-11-01

The appropriate fluence of 2.0 MeV H(sup +) ions has been shown previously to enhance the critical current density J(sub c) by a factor of two at a magnetic field of 0.9 tesla in 1000 (Angstrom) thick epitaxial films of YBa(2)Cu(3)O(7-delta) grown by the ex situ BaF2 process. The as-grown films exhibit single crystal-like behavior in both atomic ordering and J(sub c) versus temperature and magnetic field. TRIM simulations suggest that H(sup +) irradiation generates mainly point defects throughout the crystal structure. We show here that such defects produce both a large enhancement of J(sub c) for fields above 1 tesla and a significant increase in the apparent vortex pinning potential deduced from magnetization relaxation data.

Oxygen Reduction Kinetics of La2-xSrxNiO 4+delta Electrodes for Solid Oxide Fuel Cells

Science.gov (United States)

Guan, Bo

In the development of intermediate temperature solid oxide fuel cell (IT-SOFC), mixed ionic-electronic conductors (MIEC) have drawn big interests due to their both ionic and electronic species transport which can enlarge the 3-dimension of the cathode network. This thesis presents an investigation of MIEC of Ruddlesden-popper (RP) phases like K2NiF4 type La2NiO4+delta (LNO)-based oxides which have interesting transport, catalytic properties and suitable thermal expansion coefficients. The motivation of this present work is to further understand the fundamental of the effect of Sr doing on the oxygen reduction reaction (ORR) kinetics of LNO cathode. Porous symmetrical cells of La2-xSrxNiO4+delta (0≤x≤0.4) were fabricated and characterized by electrochemical impedance spectroscopy (EIS) in different PO2 from temperature range of 600˜800°C. The spectra were analyzed based on the impedance model introduced by Adler et al. The rate determining steps (RDS) for ORR were proposed and the responsible reasons were discussed. The overall polarization resistances of doped samples increase with Sr level. Surface oxygen exchange and bulk ionic diffusion co-control the ORR kinetics. With high Sr content (x=0.3, 0.4), oxygen ion transfer resistance between nickelate/electrolyte is observed. However for porous symmetrical cells it is hard to associate the resistance from EIS directly to each ORR elementary processes because of the difficulty in describing the microstructure of the porous electrode. The dense electrode configuration was adopted in this thesis. By using the dense electrode, the surface area, the thickness of electrode, the interface between electrode and electrolyte and lastly the 3PB are theoretically well-defined. Through this method, there is a good chance to distinguish the contribution of surface exchange from other processes. Dense and thin electrode layers in thickness of ˜40 mum are fabricated by using a novel spray modified pressing method. Negligible

YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} coated conductor deposited onto non-magnetic ternary alloy NiCrW RABiTS tape by in situ pulsed laser deposition

Energy Technology Data Exchange (ETDEWEB)

Tomov, R I; Kursumovic, A; Majoros, M; Glowacki, B A; Evetts, J E; Tuissi, A; Villa, E; Zamboni, M; Sun, Y; Toenies, S; Weber, H W

2003-01-01

Pulsed laser deposition of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO)/buffer (Y{sub 2}O{sub 3}, YSZ, CeO{sub 2}) heterostructures have been performed in situ onto recently developed non-magnetic oxygenation resistant NiCrW tape. The influence of the critical processing parameters on texture development are investigated and the issues involved in NiO formation and relation to the substrate surface quality are discussed. The roles of Ni poisoning YBCO as well as local cation disorder are considered as possible current limiting factors. X-ray diffraction has been used for macro-texture evaluation. Both buffers and YBCO layers show good biaxial alignment with {omega} and {phi} scans having best YBCO FWHM values of 4.0 deg. and 6.5 deg. respectively. A comparison is made with results achieved on industrial Ni{sub 50}Fe{sub 50} tape. The film morphology has been characterized using atomic force microscopy and scanning electron microscopy. The cation disorder has been studied by Raman spectroscopy. Critical temperatures of 90 K ({delta}T{sub c}=5 K) have been measured. Direct transport as well as magnetic measurements shows the critical current density J{sub c} is 0.2 MA/cm{sup 2} in self-field at liquid nitrogen temperatures.

Insulin, IGF-1, and GH Receptors Are Altered in an Adipose Tissue Depot-Specific Manner in Male Mice With Modified GH Action.

Science.gov (United States)

Hjortebjerg, Rikke; Berryman, Darlene E; Comisford, Ross; Frank, Stuart J; List, Edward O; Bjerre, Mette; Frystyk, Jan; Kopchick, John J

2017-05-01

Growth hormone (GH) is a determinant of glucose homeostasis and adipose tissue (AT) function. Using 7-month-old transgenic mice expressing the bovine growth hormone (bGH) gene and growth hormone receptor knockout (GHR-/-) mice, we examined whether changes in GH action affect glucose, insulin, and pyruvate tolerance and AT expression of proteins involved in the interrelated signaling pathways of GH, insulinlike growth factor 1 (IGF-1), and insulin. Furthermore, we searched for AT depot-specific differences in control mice. Glycated hemoglobin levels were reduced in bGH and GHR-/- mice, and bGH mice displayed impaired gluconeogenesis as judged by pyruvate tolerance testing. Serum IGF-1 was elevated by 90% in bGH mice, whereas IGF-1 and insulin were reduced by 97% and 61% in GHR-/- mice, respectively. Igf1 RNA was increased in subcutaneous, epididymal, retroperitoneal, and brown adipose tissue (BAT) depots in bGH mice (mean increase ± standard error of the mean in all five depots, 153% ± 27%) and decreased in all depots in GHR-/- mice (mean decrease, 62% ± 4%). IGF-1 receptor expression was decreased in all AT depots of bGH mice (mean decrease, 49% ± 6%) and increased in all AT depots of GHR-/- mice (mean increase, 94% ± 8%). Insulin receptor expression was reduced in retroperitoneal, mesenteric, and BAT depots in bGH mice (mean decrease in all depots, 56% ± 4%) and augmented in subcutaneous, retroperitoneal, mesenteric, and BAT depots in GHR-/- mice (mean increase: 51% ± 1%). Collectively, our findings indicate a role for GH in influencing hormone signaling in AT in a depot-dependent manner. Copyright © 2017 Endocrine Society.

Growth hormone (GH) provocative retesting of 108 young adults with childhood-onset GH deficiency and the diagnostic value of insulin-like growth factor I (IGF-I) and IGF-binding protein-3

DEFF Research Database (Denmark)

Juul, A; Kastrup, K W; Pedersen, S A

1997-01-01

.e. 45% of patients treated with GH during childhood because of isolated GHD had a normal GH response when retested in adulthood. Multiple regression analysis revealed that peak GH levels were dependent on the degree of hypopituitarism, body mass index, and duration of disease. IGF-I levels were below -2...

The Atchafalaya River Delta. Report 7. Analytical Analysis of the Development of the Atchafalaya River Delta.

Science.gov (United States)

1985-09-01

responsible for the abrupt increases in subaerial delta growth. 64. Through using satellite imagery, color infrared photog- raphy, and digital current...w RO CF = HO/A/BO/(2.-D) w (HH wo (2.-D) - 1.) + O.5/AA X2 = BO m 2.m AA a HHow(D-1.) o CF AREA = (2.wAAwB~ ww2 ) im (CKI*(1. + AmBO/HOwRO) ww2 &+ CK2 a

The GH/IGF axis in the mouse kidney

NARCIS (Netherlands)

V. Cingel-Ristic

2004-01-01

textabstractGrowth hormone (GH) is a protein hormone synthesized and secreted by somatotroph cells within the anterior pituitary predominantly under regulation of hypothalamic peptides, GH releasing hormone (GHRH) and somatostatin (SS) (1-3) (Figure 1). Further, production of GH is modulated by

High performance protonic ceramic membrane fuel cells (PCMFCs) with Ba{sub 0.5}Sr{sub 0.5}Zn{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} perovskite cathode

Energy Technology Data Exchange (ETDEWEB)

Ding, Hanping; Lin, Bin; Liu, Xingqin; Meng, Guangyao [Department of Materials Science and Engineering, University of Science and Technology of China (USTC), No. 96 Jinzhai Road, Hefei 230026 (China)

2008-09-15

Protonic ceramic membrane fuel cells (PCMFCs) based on proton-conducting electrolytes have attracted much attention because of many advantages, such as low activation energy and high energy efficiency. BaZr{sub 0.1}Ce{sub 0.7}Y{sub 0.2}O{sub 3-{delta}} (BZCY7) electrolyte based PCMFCs with stable Ba{sub 0.5}Sr{sub 0.5}Zn{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (BSZF) perovskite cathode were investigated. Using thin membrane BZCY7 electrolyte (about 15 {mu}m in thickness) synthesized by a modified Pechini method on NiO-BZCY7 anode support, PCMFCs were assembled and tested by selecting stable BSZF perovskite cathode. An open-circuit potential of 1.015 V, a maximum power density of 486 mW cm{sup -2}, and a low polarization resistance of the electrodes of 0.08 {omega} cm{sup 2} was achieved at 700 C. The results have indicated that BZCY7 proton-conducting electrolyte with BSZF cathode is a promising material system for the next generation solid oxide fuel cells. (author)

Evaluation of growth hormone (GH) action in mice: discovery of GH receptor antagonists and clinical indications.

Science.gov (United States)

Kopchick, John J; List, Edward O; Kelder, Bruce; Gosney, Elahu S; Berryman, Darlene E

2014-04-05

The discovery of a growth hormone receptor antagonist (GHA) was initially established via expression of mutated GH genes in transgenic mice. Following this discovery, development of the compound resulted in a drug termed pegvisomant, which has been approved for use in patients with acromegaly. Pegvisomant treatment in a dose dependent manner results in normalization of IGF-1 levels in most patients. Thus, it is a very efficacious and safe drug. Since the GH/IGF-1 axis has been implicated in the progression of several types of cancers, many have suggested the use of pegvisomant as an anti-cancer therapeutic. In this manuscript, we will review the use of mouse strains that possess elevated or depressed levels of GH action for unraveling many of GH actions. Additionally, we will describe experiments in which the GHA was discovered, review results of pegvisomant's preclinical and clinical trials, and provide data suggesting pegvisomant's therapeutic value in selected types of cancer. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Neutron diffraction and NQR study of the intermediate turn angle phase formed during AFI to AFII recording in YBa2Cu3-xAlxO6+#delta#

DEFF Research Database (Denmark)

Brecht, E.; Schmahl, W.W.; Fuess, H.

1997-01-01

The reordering mechanism from the antiferromagnetic phase AFI to the antiferromagnetic phase AFII in an oxygen-deficient YBa2Cu2.94Al0.06O6+delta single crystal with an oxygen content delta=0.18 in the Cu(1) layer has been studied by neutron diffraction and nuclear quadrupole resonance (NQR......). The crystal orders magnetically from the paramagnetic state to the antiferromagnetic AFI state at the Neel temperature T-N=403 K with an empirical critical exponent of beta = 0.26. Reordering to the antiferromagnetic AFII state sets in at T-2 = 12 K. In both the AFI and AFII phases the ordered magnetic...... as a function of temperature. This result indicates unequivocally that the AFIAFII reordering takes place via a noncollinear intermediate turn angle phase AFI+II....

Structural phase transformation in K2SeO4

International Nuclear Information System (INIS)

Iizumi, M.; Axe, J.D.; Shirane, G.; Shimaoka, K.

1977-01-01

Successive phase transformations in K 2 SeO 4 at T 1 = 130 K and T/sub c/ = 93 K were studied by the neutron-scattering technique. The superlattice reflections in the intermediate phase were found to be incommensurate with the lattice periodicity. The wave vector characterizing the reflections is q/sub delta/ = (1-delta) a*/3 with delta = 0.07 at 122.5 K. The deviation delta decreases with decreasing temperature with an apparently discontinuous jump to zero at T/sub c/. Below this temperature, the crystal remains commensurate and is known to be ferroelectric. The incommensurate-commensurate transition and the simultaneous occurrence of the commensurate phase and the spontaneous polarization are discussed using a Landau-type expansion of the free energy in which a term proportional to Q 3 (q/sub delta/) P/sub z/ (q 3 /sub delta/) plays an essential role in driving the incommensurate-commensurate phase transformation and in inducing the spontaneous polarization. Here, Q (q/sub delta/) is the amplitude of the primary atomic displacements with wave vector q/sub delta/ and P/sub z/(q 3 /sub delta/) is the polarization wave with wave vector q 3 /sub delta/ = 3delta (a*/3) and becomes the macroscopic polarization below T/sub c/. Above T/sub i/, a Σ 2 optic-phonon branch along (xi,0,0) shows a striking softening and ω/sub j/(q) for q approx. (1/3,0,0) tends to zero at T/sub i/. The softening results from a temperature-dependent decrease of the interlayer forces with ranges a/2 and a (a is one unit-cell length along the a axis) in the presence of strong and persisting forces with a range 3a/2. The intensities of the soft phonon were measured about different reciprocal-lattice points and were used to determine the nature of the soft-phonon mode and suggest a coupled translation of potassium ions with rotational motion of SeO 4 groups to be the origin of the lattice instability

Continuous 24-hour intravenous infusion of recombinant human growth hormone (GH)-releasing hormone-(1-44)-amide augments pulsatile, entropic, and daily rhythmic GH secretion in postmenopausal women equally in the estrogen-withdrawn and estrogen-supplemented states.

Science.gov (United States)

Evans, W S; Anderson, S M; Hull, L T; Azimi, P P; Bowers, C Y; Veldhuis, J D

2001-02-01

How estrogen amplifies GH secretion in the human is not known. The present study tests the clinical hypothesis that estradiol modulates the stimulatory actions of a primary GH feedforward signal, GHRH. To this end, we investigated the ability of short-term (7- to 12-day) supplementation with oral estradiol vs. placebo to modulate basal, pulsatile, entropic, and 24-h rhythmic GH secretion driven by a continuous iv infusion of recombinant human GHRH-(1--44)-amide vs. saline in nine healthy postmenopausal women. Volunteers underwent concurrent blood sampling every 10 min for 24 h on four occasions in a prospectively randomized, single blind, within-subject cross-over design (placebo/saline, placebo/GHRH, estradiol/saline, estradiol/GHRH). Intensively sampled serum GH concentrations were quantitated by ultrasensitive chemiluminescence assay. Basal, pulsatile, entropic (feedback-sensitive), and 24-h rhythmic modes of GH secretion were appraised by deconvolution analysis, the approximate entropy (ApEn) statistic, and cosine regression, respectively. ANOVA revealed that continuous iv infusion of GHRH in the estrogen-withdrawn (control) milieu 1) amplified individual basal (P = 0.00011) and pulsatile (P < 10(-13)) GH secretion rates by 12- and 11-fold, respectively; 2) augmented GH secretory burst mass and amplitude each by 10-fold (P < 10(-11)), without altering GH secretory burst frequency, duration, or half-life; 3) increased the disorderliness (ApEn) of GH release patterns (P = 0.0000002); 4) elevated the mesor (cosine mean) and amplitude of the 24-h rhythm in serum GH concentrations by nearly 30-fold (both P < 10(-12)); 5) induced a phase advance in the clocktime of the GH zenith (P = 0.021); and 6) evoked a new 24-h rhythm in GH secretory burst mass with a maximum at 0018 h GH (P < 10(-3)), while damping the mesor of the 24-h rhythm in GH interpulse intervals (P < 0.025). Estradiol supplementation alone 1) increased the 24-h mean and integrated serum GH concentration

The robustness of diagnostic tests for GH deficiency in adults

DEFF Research Database (Denmark)

Andersen, Marianne

2015-01-01

with recombinant human GH. There is, however, an ongoing debate on how to diagnose GHD, especially in adults. A GH response below the cut-off limit of a GH-stimulation test is required in most cases for establishing GHD in adults. No 'gold standard' GH-stimulation test exists, but some GH stimulation tests may...

Modulation-doped β-(Al0.2Ga0.8)2O3/Ga2O3 field-effect transistor

Science.gov (United States)

Krishnamoorthy, Sriram; Xia, Zhanbo; Joishi, Chandan; Zhang, Yuewei; McGlone, Joe; Johnson, Jared; Brenner, Mark; Arehart, Aaron R.; Hwang, Jinwoo; Lodha, Saurabh; Rajan, Siddharth

2017-07-01

Modulation-doped heterostructures are a key enabler for realizing high mobility and better scaling properties for high performance transistors. We report the realization of a modulation-doped two-dimensional electron gas (2DEG) at the β-(Al0.2Ga0.8)2O3/Ga2O3 heterojunction by silicon delta doping. The formation of a 2DEG was confirmed using capacitance voltage measurements. A modulation-doped 2DEG channel was used to realize a modulation-doped field-effect transistor. The demonstration of modulation doping in the β-(Al0.2Ga0.8)2O3/Ga2O3 material system could enable heterojunction devices for high performance electronics.

Isotopologue fractionation during N(2)O production by fungal denitrification.

Science.gov (United States)

Sutka, Robin L; Adams, Gerard C; Ostrom, Nathaniel E; Ostrom, Peggy H

2008-12-01

Identifying the importance of fungi to nitrous oxide (N2O) production requires a non-intrusive method for differentiating between fungal and bacterial N2O production such as natural abundance stable isotopes. We compare the isotopologue composition of N2O produced during nitrite reduction by the fungal denitrifiers Fusarium oxysporum and Cylindrocarpon tonkinense with published data for N2O production during bacterial nitrification and denitrification. The fractionation factors for bulk nitrogen isotope values for fungal denitrification were in the range -74.7 to -6.6 per thousand. There was an inverse relationship between the absolute value of the fractionation factors and the reaction rate constant. We interpret this in terms of variation in the relative importance of the rate constants for diffusion and enzymatic reduction in controlling the net isotope effect for N2O production during fungal denitrification. Over the course of nitrite reduction, the delta(18)O values for N2O remained constant and did not exhibit a relationship with the concentration characteristic of an isotope effect. This probably reflects isotopic exchange with water. Similar to the delta(18)O data, the site preference (SP; the difference in delta(15)N between the central and outer N atoms in N2O) was unrelated to concentration during nitrite reduction and, therefore, has the potential to act as a conservative tracer of production from fungal denitrification. The SP values of N2O produced by F. oxysporum and C. tonkinense were 37.1 +/- 2.5 per thousand and 36.9 +/- 2.8 per thousand, respectively. These SP values are similar to those obtained in pure culture studies of bacterial nitrification but quite distinct from SP values for bacterial denitrification. The large magnitude of the bulk nitrogen isotope fractionation and the delta(18)O values associated with fungal denitrification are distinct from bacterial production pathways; thus multiple isotopologue data holds much promise for

Evaluation of in vivo [corrected] biological activity of new agmatine analogs of growth hormone-releasing hormone (GH-RH)

Science.gov (United States)

Bokser, L; Zarandi, M; Schally, A V

1990-01-01

The effects of agmatine analogs of growth hormone releasing hormone (GH-RH) were compared to GH-RH(1-29)-NH2 after intravenous (iv) and subcutaneous (sc) administration to pentobarbital-anesthetized male rats. After the iv injection, the analogs [desNH2-Tyr1,Ala15,Nle27] GH-RH(1-28)Agm (MZ-2-51); [desNH2-Tyr1,D-Lys12,Ala15,Nle27] GH-RH(1-28)Agm (MZ-2-57); [desNH2-Tyr1,Ala15,D-Lys21,Nle27] GH-RH(1-28)Agm (MZ-2-75) and [desNH2-Tyr1, D-Lys12,21, Ala15, Nle27] GH-RH(1-28)Agm (MZ-2-87) showed a potency equivalent to 4.4, 1.9, 1.07 and 1.03 times that of GH-RH (1-29)-NH2, respectively, at 5 min and 5.6, 1.8, 1.9 and 1.8 times higher, respectively, at 15 min. After sc administration, analogs MZ-2-51, MZ-2-57 and MZ-2-75 showed to be 34.3, 14.3 and 10.5 times more potent than the parent hormone at 15 min and 179.1, 88.9 and 45.0 times more active, respectively, at 30 min. In addition, MZ-2-51 had prolonged GH-releasing activity as compared to the standard. We also compared the activity of MZ-2-51 and MZ-2-57 with their homologous L-Arg and D-Arg analogs [desNH2-Tyr1,Ala15,Nle27] GH-RH(1-29)-NH2 (MZ-2-117), [des-NH2Tyr1,D-Lys12, Ala15, Nle27] GH-RH(1-29)NH2 (MZ-2-123) and [desNH2-Tyr1,D-Lys12,Ala15, Nle27,D-Arg29] GH-RH(1-29)NH2 (MZ-2-135) after intramuscular (im) injection. MZ-2-51 induced a somewhat greater GH release than MZ-2-117 at 15 min, both responses being larger than the controls (p less than 0.01) at 15 and 30 min. MZ-2-57, MZ-2-123 and MZ-2-135 given i.m. were able to stimulate GH release only at 15 minutes (p less than 0.05). Animals injected i.m. with MZ-2-51, but not with MZ-2-117, showed GH levels significantly higher than the control group (p less than 0.05) at 60 min. GH-RH(1-29)NH2 had low activity intramuscularly when tested at a dose of 2.5 micrograms. No toxic effects were observed after the iv administration of 1 mg/kg of Agm GH-RH analogs. These results indicate that our Agm analogs are active iv, sc and im and that the substitutions made in these

Thermal expansion of superconducting phases Bi sub 2 Sr sub 2 Ca sub n-1 Cu sub n O sub 2n+2+. delta. with n=1,2,3. Termicheskoe rasshirenie sverkhprovodyashchikh faz Bi sub 2 Sr sub 2 Ca sub n-1 Cu sub n O sub 2n+2+. delta. s n=1,2,3

Energy Technology Data Exchange (ETDEWEB)

Zhurov, V V; Ivanov, S A [Nauchno-Issledovatel' skij Fiziko-Khimicheskij Inst., Moscow (USSR); Bush, A A; Romanov, B N [Moskovskij Inst. Radiotekhniki, Ehlektroniki i Avtomatiki, Moscow (USSR)

1990-10-01

Consideration is given to results of X-ray diffraction studies of temperature dependences of a{sub 0},c{sub 0} sublattice parameters of Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+2+}{delta} superconducting phases with n=1,2,3 (2201, 2212, 2223) in 90-1000 K range. The obtained dependences are composed of some temperature linear sections, where values of thermal coefficients of linear expansion {alpha}{sub a}, {alpha}{sub c} were determined for all examined phases. During first heating of samples of 2212 phase a{sub 0}(T), c{sub 0}(T) dependences deviate in {approx equal}500-700 K range from linear ones till the occurence of a section with negative a{sub c}. After heating of 2212 phase up to T>{approx equal}700 K and cooling down to 300 K, a{sub 0},c{sub 0} parameters decrease by {approx equal}0.006 and 0.08 A respectively. Data on the effect of preparation method and thermal prehistory of 2212 samples and on relative content of calcium atoms in them for these anomalies were obtained. Some possible reasons of their occurence were analyzed.

Dermal absorption of the insecticide lindane (1 delta, 2 delta, 3 beta, 4 delta, 5 delta, 6 beta-hexachlorocyclohexane) in rats and rhesus monkeys: Effect of anatomical site

International Nuclear Information System (INIS)

Moody, R.P.; Ritter, L.

1989-01-01

Dermal absorption of the insecticide lindane (1 delta, 2 delta, 3 beta, 4 delta, 5 delta, 6 beta-hexachlorocyclohexane) was determined in rats and rhesus monkeys. Lindane is in widespread use as a 1% cream or lotion scabicide formulation and as a 1% miticide shampoo for body lice control in humans. Results obtained following our in vivo dermal absorption procedure demonstrated that 18 +/- 4.1%, 34 +/- 5.2%, and 54 +/- 26.3% of the applied dose was absorbed following topical applications at a rate of 1.5 micrograms/cm2 (6.2 micrograms/100 microliters of acetone) of the 14C-labeled pesticide to 4.2-cm2 regions of the forearm (n = 8), forehead (n = 7), and palm (n = 4) of rhesus monkeys, respectively. Dose sites were washed with soapy water 24 h posttreatment. Comparative studies in rats (n = 5) dosed middorsally demonstrated 31 +/- 9.5% absorption. Statistical analysis of the 14C excretion kinetics demonstrated slower clearance of lindane from rats than monkey forearm, forehead, or palm. Intramuscular (im) injections of 14C-lindane gave 52 +/- 7.1% recovery in monkey (n = 8) and 64 +/- 5.9% in rats (n = 5), suggesting body storage of this lipophilic chemical

Auxological criteria for the diagnosis of GH-dependent short stature and prescription of rGH: problems and pitfalls

Directory of Open Access Journals (Sweden)

Giulio Gilli

2007-12-01

Full Text Available Recombinant growth hormone (rGH administration is a cornerstone in the treatment of short stature secondary to GH deficit. Since its introduction in the 80s, the population of short patients with an indication to rGH therapy has clearly broadened, probably because of increased awareness by patients and physicians. Since rGH therapy is demanding for patients and expensive, the Italian National Health Service, like other third payers and regulatory authorities, regulates its prescription according to criteria listed in the Nota AIFA 39. This paper illustrates pitfalls and difficulties paediatricians may encounter when assessing short stature patients in order to decide upon the opportunity and possibility to initiate rGH therapy through the exposition of four emblematic, though hypothetical, clinical histories. In the discussion, the Authors highlight some of the most critical points in the formulation of the Nota 39, among which are the lack of clear reference values, neglecting of parental height targets and therapeutic responses, as well as some omissions in methodology specifications.

Improved growth response to GH treatment in irradiated children

International Nuclear Information System (INIS)

Lannering, B.; Albertsson-Wikland, K.

1989-01-01

The growth response to two years of GH treatment was studied in fifteen children after radiotherapy for a cranial tumour. The growth response was compared to that of short children (-2 SD) and that of children with idiopathic growth hormone deficiency (GHD) of similar ages. All children were treated with hGH 0.1 IU/kg/day s.c.; which is a higher dose and frequency than previously reported for irradiated children. On this protocol the growth rate increased 5.0 +- 0.5 cm/y (mean +- SEM) the first year and 3.8 +- 0.7 cm/y the second year compared to the growth rate the year before GH-treatment. Although the net gain in growth was higher than previously reported, the first year growth response was significantly reduced (p less than 0.05) compared to that of GHD-children (7.6 +- 0.5 cm/y) but exceeded (p less than 0.05) that of short children (3.4 +- 0.3 cm/y). The median spontaneous 24 h-GH secretion was 209 mU/l in the short children, 52 mU/l in the irradiated children and 16 mU/l in the idiopathic GHD children. Thus the growth increment varied inversely to the spontaneous GH secretion observed in the three groups

Inter- and intraplane softening of the vortex structure in Bi sub 2. 1 Sr sub 1. 9 Ca sub 0. 9 Cu sub 2 O sub 8+. delta. : a two-step transition. [Bi-Sr-Ca-Cu-O

Energy Technology Data Exchange (ETDEWEB)

Yazyi, J; Arribere, A; Duran, C; Cruz, F de la [Centro Atomico Bariloche and Inst. Balseiro, Rio Negro (Argentina); Mitzi, D B; Kapitulnik, A [Stanford Univ., CA (United States)

1991-12-15

High Q mechanical oscillator and AC susceptibility techniques have been used to study vortex dynamics in high quality single crystals of Bi{sub 2.1}Sr{sub 1.9}Ca{sub 0.9}Cu{sub 2}O{sub 8+{delta}} over a wide range of magnetic fields and different relative orientations between the magnetic field and the crystalline c-axis. Our results confirm the existence of two transitions in the vortex response. We show that the transition at lower temperatures is associated to currents flowing across the Cu-O planes and the other one to currents in the planes. This means that the reversible region of the phase diagram is reached in two steps when increasing temperature. (orig.).

A single amino acid substitution in the exoplasmic domain of the human growth hormone (GH) receptor confers familial GH resistance (Laron syndrome) with positive GH-binding activity by abolishing receptor homodimerization.

Science.gov (United States)

Duquesnoy, P; Sobrier, M L; Duriez, B; Dastot, F; Buchanan, C R; Savage, M O; Preece, M A; Craescu, C T; Blouquit, Y; Goossens, M

1994-01-01

Growth hormone (GH) elicits a variety of biological activities mainly mediated by the GH receptor (GHR), a transmembrane protein that, based on in vitro studies, seemed to function as a homodimer. To test this hypothesis directly, we investigated patients displaying the classic features of Laron syndrome (familial GH resistance characterized by severe dwarfism and metabolic dysfunction), except for the presence of normal binding activity of the plasma GH-binding protein, a molecule that derives from the exoplasmic-coding domain of the GHR gene. In two unrelated families, the same GHR mutation was identified, resulting in the substitution of a highly conserved aspartate residue by histidine at position 152 (D152H) of the exoplasmic domain, within the postulated interface sequence involved in homodimerization. The recombinant mutated receptor protein was correctly expressed at the plasma membrane. It displayed subnormal GH-binding activity, a finding in agreement with the X-ray crystal structure data inferring this aspartate residue outside the GH-binding domain. However, mAb-based studies suggested the critical role of aspartate 152 in the proper folding of the interface area. We show that a recombinant soluble form of the mutant receptor is unable to dimerize, the D152H substitution also preventing the formation of heterodimers of wild-type and mutant molecules. These results provide in vivo evidence that monomeric receptors are inactive and that receptor dimerization is involved in the primary signalling of the GH-associated growth-promoting and metabolic actions. Images PMID:8137822

Stable, easily sintered BaCe{sub 0.5}Zr{sub 0.3}Y{sub 0.16}Zn{sub 0.04}O{sub 3-{delta}} electrolyte-based protonic ceramic membrane fuel cells with Ba{sub 0.5}Sr{sub 0.5}Zn{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} perovskite cathode

Energy Technology Data Exchange (ETDEWEB)

Lin, Bin; Hu, Mingjun; Ma, Jianjun; Meng, Guangyao [Department of Materials Science and Engineering, University of Science and Technology of China (USTC), 96 Jinzhai Road, Hefei, Anhui 230026 (China); Jiang, Yinzhu [Department of Materials Science and Engineering, University of Science and Technology of China (USTC), 96 Jinzhai Road, Hefei, Anhui 230026 (China); Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Tao, Shanwen [Department of Chemistry, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

2008-09-01

A stable, easily sintered perovskite oxide BaCe{sub 0.5}Zr{sub 0.3}Y{sub 0.16}Zn{sub 0.04}O{sub 3-{delta}} (BCZYZn) as an electrolyte for protonic ceramic membrane fuel cells (PCMFCs) with Ba{sub 0.5}Sr{sub 0.5}Zn{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (BSZF) perovskite cathode was investigated. The BCZYZn perovskite electrolyte synthesized by a modified Pechini method exhibited higher sinterability and reached 97.4% relative density at 1200 C for 5 h in air, which is about 200 C lower than that without Zn dopant. By fabricating thin membrane BCZYZn electrolyte (about 30 {mu}m in thickness) on NiO-BCZYZn anode support, PCMFCs were assembled and tested by selecting stable BSZF perovskite cathode. An open-circuit potential of 1.00 V, a maximum power density of 236 mW cm{sup -2}, and a low polarization resistance of the electrodes of 0.17 {omega} cm{sup 2} were achieved at 700 C. This investigation indicated that proton conducting electrolyte BCZYZn with BSZF perovskite cathode is a promising material system for the next generation solid oxide fuel cells. (author)

Rapid processing method for solution deposited YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} thin films

Energy Technology Data Exchange (ETDEWEB)

Dawley, J.T.; Clem, P.G.; Boyle, T.J.; Ottley, L.M.; Overmyer, D.L.; Siegal, M.P

2004-02-01

YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films, deposited on buffered metal substrates, are the primary candidate for second-generation superconducting (SC) wires, with applications including expanded power grid transmission capability, compact motors, and enhanced sensitivity magnetic resonance imaging. Feasibility of manufacturing such superconducting wires is dependent on high processing speed, often a limitation of vapor and solution-based YBCO deposition processes. In this work, YBCO films were fabricated via a new diethanolamine-modified trifluoroacetic film solution deposition method. Modifying the copper chemistry of the YBCO precursor solution with diethanolamine enables a hundredfold decrease in the organic pyrolysis time required for MA/cm{sup 2} current density (J{sub c}) YBCO films, from multiple hours to {approx}20 s in atmospheric pressure air. High quality, {approx}0.2 {mu}m thick YBCO films with J{sub c} (77 K) values {>=}2 MA/cm{sup 2} at 77 K are routinely crystallized from these rapidly pyrolyzed films deposited on LaAlO{sub 3}. This process has also enabled J{sub c} (77 K)=1.1 MA/cm{sup 2} YBCO films via 90 m/h dip-coating on Oak Ridge National Laboratory RABiTS textured metal tape substrates. This new YBCO solution deposition method suggests a route toward inexpensive and commercializable {approx}$10/kA m solution deposited YBCO coated conductor wires.

Development of Bulk Bi2+xSr3-yCa yCu 2O8+delta Superconductors by Partial-Melting Route for Fault Current Limiters Application

Directory of Open Access Journals (Sweden)

Bojan A. Marinkovic

2002-06-01

Full Text Available The production of bulk Bi2+xSr3-yCa yCu 2O8+delta (Bi-2212 superconductors for fault current limiter application was developed via a partial-melting route. Aiming high Ic (critical current, which is the essential superconducting characteristic for application of this material in the construction of Fault Current Limiters (FCL, the produced blocks have predominance of Bi-2212 phase (83 wt%, which characterizes with high values of zero and onset transport critical temperature of 92K and 97.5K, respectively. A relatively low transition width, deltaT, from the superconducting to the normal state of 5.5K, revealed a good intergrain connectivity. Consequently, current measurements on the blocks of Bi-2212 show promising Ic values of 230A and 850A for direct and alternate current, respectively. It is expected that further increases in the Ic values will depend on the elimination of an observed amorphous phase and further reduction of amount and grain sizes of secondary phases, still present in the blocks obtained by the proposed partial-melting route. This may be achieved by a further optimization of the partial-melting processing parameters.

Structure and crystallization kinetics of Bi{sub 2}O{sub 3}-B{sub 2}O{sub 3} glasses

Energy Technology Data Exchange (ETDEWEB)

Cheng Yin [College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Xiao Hanning [College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China)]. E-mail: zjbcy@126.com; Guo Wenming [College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Guo Weiming [College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China)

2006-05-15

The experimental IR (infrared spectra) and differential scanning calorimetry (DSC) curves of Bi{sub 2}O{sub 3}-B{sub 2}O{sub 3} glasses, containing 30-60 mol% Bi{sub 2}O{sub 3}, have been investigated in the article. The composition dependence of IR absorption suggests that addition of Bi{sub 2}O{sub 3} results in a change in the short-range order structure of the borate matrix. The increase of Bi{sub 2}O{sub 3} content causes a progressive conversion of [BO{sub 3}] to [BO{sub 4}] units. Bi{sub 2}O{sub 3}, in the form of [BiO{sub 6}] octahedral units, plays the role of glass former. The crystallization kinetics of Bi{sub 2}O{sub 3}-B{sub 2}O{sub 3} glasses were described by thermal stability indexes (k {sub gl}, {delta}T), activation energy (E) for crystallization and numerical factors(n, m) depending on the nucleation process and growth morphology, which were calculated by Satava method and the modified Ozawa-Chen method. When Bi{sub 2}O{sub 3} {<=} 45 mol%, the increase of Bi{sub 2}O{sub 3} tends to improve the thermal stabilities of the glasses. In this case, k {sub gl} may be more suitable for estimating the glass thermal stability in above composition range than {delta}T. A further increase of Bi{sub 2}O{sub 3} content will increase the crystallization trends of investigated glasses. Two possible kinds of growth mechanisms were involved in Bi{sub 2}O{sub 3}-B{sub 2}O{sub 3} glasses: one-dimensional growth and two-dimensional growth. Moreover, structures of crystallized glasses were observed by X-ray diffraction (XRD). BiBO{sub 3} crystal with special non-linear optical properties can be obtained when Bi{sub 2}O{sub 3} {>=} 50 mol%.

Dominant dwarfism in transgenic rats by targeting human growth hormone (GH) expression to hypothalamic GH-releasing factor neurons.

OpenAIRE

Flavell, D M; Wells, T; Wells, S E; Carmignac, D F; Thomas, G B; Robinson, I C

1996-01-01

Expression of human growth hormone (hGH) was targeted to growth hormone-releasing (GRF) neurons in the hypothalamus of transgenic rats. This induced dominant dwarfism by local feedback inhibition of GRF. One line, bearing a single copy of a GRF-hGH transgene, has been characterized in detail, and has been termed Tgr (for Transgenic growth-retarded). hGH was detected by immunocytochemistry in the brain, restricted to the median eminence of the hypothalamus. Low levels were also detected in the...

Electronic structure of layered ferroelectric high-k titanate La{sub 2}Ti{sub 2}O{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Atuchin, V V [Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Gavrilova, T A [Laboratory of Electron Microscopy and Submicron Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Grivel, J-C [Materials Research Department, National Laboratory for Sustainable Energy, Technical University of Denmark, Frederiksborgvej 399, DK-4000, Roskilde (Denmark); Kesler, V G, E-mail: atuchin@thermo.isp.nsc.r [Laboratory of Physical Bases of Integrated Microelectronics, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation)

2009-02-07

The electronic structure of binary titanate La{sub 2}Ti{sub 2}O{sub 7} has been studied by x-ray photoelectron spectroscopy. Spectral features of valence band and all constituent element core levels have been considered. The Auger parameters of titanium and oxygen in La{sub 2}Ti{sub 2}O{sub 7} are determined as alpha{sub Ti} = 872.4 and alpha{sub O} = 1042.3 eV. Chemical bonding effects have been discussed with binding energy (BE) differences DELTA{sub Ti} = (BE O 1s - BE Ti 2p{sub 3/2}) = 71.6 eV and DELTA{sub La} = (BE La 3d{sub 5/2} - BE O 1s) = 304.7 eV as key parameters in comparison with those in several titanium- and lanthanum-bearing oxides.

Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub delta/ thin films grown by a simple spray deposition technique

Energy Technology Data Exchange (ETDEWEB)

Gupta, A.; Koren, G.; Giess, E.A.; Moore, N.R.; O' Sullivan, E.J.M.; Cooper, E.I.

1988-01-11

The preparation of high T/sub c/ superconducting thin films of Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-//sub delta/ on (100) single crystals of MgO, ZrO/sub 2/ with 9% Y/sub 2/O/sub 3/ (yttria stabilized zirconia, or YSZ), and SrTiO/sub 3/ using a simple spray deposition technique is described. Typical film growth procedure involves (a) the spraying of a stoichiometric solution of the nitrate precursors on the heated substrate (180 /sup 0/C), (b) prebaking in air of the sprayed film (20 min at 500 /sup 0/C), and (c) oven annealing of the film under flowing O/sub 2/ (900--950 /sup 0/C followed by slow cooling to 200 /sup 0/C in about 3 h). X-ray diffraction analysis of the films after each of the growing steps mentioned above shows primarily the presence of crystalline phases of the nitrates, the oxides, and the orthorhombic superconducting phase, respectively. Resistivity versus temperature measurements show that the onset and completion of the superconductive transition occur at 92 and 87 K, respectively, in films on YSZ substrate; at 95 and 80 K, respectively, in films on SrTiO/sub 3/ substrate; and at 82 and 77 K, respectively, in films on MgO substrate.

Similar effects of long-term exogenous growth hormone (GH) on bone and muscle parameters: a pQCT study of GH-deficient and small-for-gestational-age (SGA) children.

Science.gov (United States)

Schweizer, Roland; Martin, David D; Haase, Martin; Roth, Johannes; Trebar, Branko; Binder, Gerhard; Schwarze, C Philipp; Ranke, Michael B

2007-11-01

Treatment with GH in short children has focused on height development. Little is known about the concomitant changes in muscle mass, bone structure and bone strength. Muscle area as well as parameters of bone architecture (bone mineral content, BMC; volumetric cortical density, total bone area, TBA; cortical area, cortical thickness, CT; and marrow area) were measured by means of pQCT (Stratec) at 65% of the proximal length of the forearm. The strength-strain index (SSI) was calculated as an indicator of bone strength. Prepubertal children with GHD (mean values: age; 7.2 years; height SDS=-2.9 SDS; GH dose: 30 microg/kg/d) were followed at 0, 6, 12 (n=74) and 24 (n=55) months. Prepubertal children with SGA (mean values: age: 7.1 years; height SDS=-3.4 SDS; GH dose: 55 mug/kg/d) were followed at 0, 6, 12 (n=47) and 24 (n=35) months. Both groups showed a similar increase in height. At GH start, muscle mass and bone characteristics were lower than normal but similar in SGA vs. GHD. Muscle area (mean values, SDS) increased from -3.0 to -1.5 in SGA and from -2.4 to -1.0 in GHD. Bone geometry changed in a biphasic mode, with an increase in total bone area and lowering of bone mineral content (BMC) during the first 12 months, followed by an increase of BMC and CT thereafter. SSI (mean values, mm(3)) improved from 78 to 114 in GHD and from 62 to 101 in SGA after 24 months on GH. The increment in terms of SDS did not reach significance in SGA. SSI correlated positively with muscle area before and during GH treatment. Bone strength and muscle mass are impaired in prepubertal children with GHD and SGA. Exogenous GH can indirectly improve bone structure and strength by inducing an increase in muscle mass. Our findings support the assumption that, in SGA, there is impaired tissue responsiveness to GH.

Ab initio study of thermoelectric properties of doped SnO_2 superlattices

International Nuclear Information System (INIS)

Borges, P.D.; Silva, D.E.S.; Castro, N.S.; Ferreira, C.R.; Pinto, F.G.; Tronto, J.; Scolfaro, L.

2015-01-01

Transparent conductive oxides, such as tin dioxide (SnO_2), have recently shown to be promising materials for thermoelectric applications. In this work we studied the thermoelectric properties of Fe-, Sb- and Zn-uniformly doping and co-doping SnO_2, as well as of Sb and Zn planar (or delta)-doped layers in SnO_2 forming oxide superlattices (SLs). Based on the semiclassical Boltzmann transport equations (BTE) in conjunction with ab initio electronic structure calculations, the Seebeck coefficient (S) and figure of merit (ZT) are obtained for these systems, and are compared with available experimental data. The delta doping approach introduces a remarkable modification in the electronic structure of tin dioxide, when compared with the uniform doping, and colossal values for ZT are predicted for the delta-doped oxide SLs. This result is a consequence of the two-dimensional electronic confinement and the strong anisotropy introduced by the doped planes. In comparison with the uniformly doped systems, our predictions reveal a promising use of delta-doped SnO_2 SLs for enhanced S and ZT, which emerge as potential candidates for thermoelectric applications. - Graphical abstract: Band structure and Figure of merit for SnO2:Sb superlattice along Z direction, P. D. Borges, D. E. S. Silva, N. S. Castro, C. R. Ferreira, F. G. Pinto, J. Tronto and L. Scolfaro, Ab initio study of thermoelectric properties of doped SnO2 superlattices. - Highlights: • Thermoelectric properties of SnO_2-based alloys and superlattices. • High figure of merit is predicted for planar-doped SnO_2 superlattices. • Nanotechnology has an important role for the development of thermoelectric devices.

Energy homeostasis targets chromosomal reconfiguration of the human GH1 locus.

Science.gov (United States)

Vakili, Hana; Jin, Yan; Cattini, Peter A

2014-11-01

Levels of pituitary growth hormone (GH), a metabolic homeostatic factor with strong lipolytic activity, are decreased in obese individuals. GH declines prior to the onset of weight gain in response to excess caloric intake and hyperinsulinemia; however, the mechanism by which GH is reduced is not clear. We used transgenic mice expressing the human GH (hGH) gene, GH1, to assess the effect of high caloric intake on expression as well as the local chromosome structure of the intact GH1 locus. Animals exposed to 3 days of high caloric intake exhibited hyperinsulinemia without hyperglycemia and a decrease in both hGH synthesis and secretion, but no difference in endogenous production of murine GH. Efficient GH1 expression requires a long-range intrachromosomal interaction between remote enhancer sequences and the proximal promoter region through "looping" of intervening chromatin. High caloric intake disrupted this interaction and decreased both histone H3/H4 hyperacetylation and RNA polymerase II occupancy at the GH1 promoter. Incorporation of physical activity muted the effects of excess caloric intake on insulin levels, GH1 promoter hyperacetylation, chromosomal architecture, and expression. These results indicate that energy homeostasis alters postnatal hGH synthesis through dynamic changes in the 3-dimensional chromatin structure of the GH1 locus, including structures required for cell type specificity during development.

Oxygen nonstoichiometry and ionic transport properties of La0.4Sr0.6CoO3-delta .

Science.gov (United States)

Sitte, W; Bucher, E; Benisek, A; Preis, W

2001-09-01

Homogeneous samples of La0.4Sr0.6CoO3-delta were obtained by the glycine nitrate process. The oxygen nonstoichiometry was determined from oxygen exchange measurements as a function of oxygen partial pressure (10(-4) bar PO2 PO2-range between 10(-4) and 10(-2) bar to yield D and the ionic conductivity sigma(i) from the long time solution of the diffusion equation. Values for D from polarization measurements at T= 775 degrees C and from oxygen exchange measurements at T= 725 degrees C are in good agreement with each other. D and sigma(1) increase with increasing PO2 (10(-4) to 10(-2) bar). The ionic conductivity shows a maximum at 3-delta approximately 2.82 and decreases with decreasing oxygen content indicating the possible formation of vacancy ordered structures.

The surface chemistry of Cu in the presence of CO2 and H2O

Energy Technology Data Exchange (ETDEWEB)

Deng, Xingyi; Verdaguer, Albert; Herranz, Tirma; Weis, Christoph; Bluhm, Hendrik; Salmeron, Miquel

2008-07-16

The chemical nature of copper and copper oxide (Cu{sub 2}O) surfaces in the presence of CO{sub 2} and H{sub 2}O at room temperature was investigated using ambient pressure x-ray photoelectron spectroscopy. The studies reveal that in the presence of 0.1 torr CO{sub 2} several species form on the initially clean Cu, including carbonate CO{sub 3}{sup 2}, CO{sub 2}{sup {delta}-} and C{sup 0}, while no modifications occur on an oxidized surface. The addition of 0.1 ML Zn to the Cu results in the complete conversion of CO{sub 2}{sup {delta}-} to carbonate. In a mixture of 0.1 torr H{sub 2}O and 0.1 torr CO{sub 2}, new species are formed, including hydroxyl, formate and methoxy, with H{sub 2}O providing the hydrogen needed for the formation of hydrogenated species.

GH activity and markers of inflammation

DEFF Research Database (Denmark)

Andreassen, Mikkel; Frystyk, Jan; Faber, Jens

2012-01-01

The GH/IGF1 axis may modulate inflammatory processes. However, the relationship seems complicated as both pro- and anti-inflammatory effects have been demonstrated.......The GH/IGF1 axis may modulate inflammatory processes. However, the relationship seems complicated as both pro- and anti-inflammatory effects have been demonstrated....

The role of interfacial defects in enhancing the critical current density of YBa2Cu3O7-delta coatings

Energy Technology Data Exchange (ETDEWEB)

Foltyn, Stephen R [Los Alamos National Laboratory; Wang, Haiyan [Los Alamos National Laboratory; Civale, Leonardo [Los Alamos National Laboratory; Maiorov, Boris A [Los Alamos National Laboratory; Jia, Quanxi [Los Alamos National Laboratory

2009-01-01

The critical current density (J{sub c}) of YBa{sub 2}Cu{sub 3}0{sub 7-{delta}} (YBCO) films can approach 10 MA/cm{sup 2} at 77 K in self field , but only for very thin films. We have shown previously that strong thickness dependence results if J{sub c} is enhanced near the film-substrate interface. In the present work we investigate interfacial enhancement using laser-deposited YBCO films on NdGaO{sub 3} substrates, and find that we can adjust deposition conditions to switch the enhancement on and off. Interestingly, we find that the 'on' state is accompanied by interfacial misfit dislocations, establishing an unambiguous correlation between enhanced J{sub c} and dislocations at the film-substrate interface.

Quark sea and the. delta. I=1/2 rule

Energy Technology Data Exchange (ETDEWEB)

Donoghue, J F [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics; Golowich, E [Massachusetts Univ., Amherst (USA)

1977-08-29

The effect on nonleptonic processes of quark-antiquark pairs due to quantum chromodynamics is studied. Their presence improves agreement between theory and experiment for hyperon decays. In kaon decays a new ..delta..I=1/2 contribution is found, but ..delta..I=3/2 effects are still too large to be in agreement.

PROMIS GH (Patient-Reported Outcomes Measurement Information System Global Health) Scale in Stroke: A Validation Study.

Science.gov (United States)

Katzan, Irene L; Lapin, Brittany

2018-01-01

The International Consortium for Health Outcomes Measurement recently included the 10-item PROMIS GH (Patient-Reported Outcomes Measurement Information System Global Health) scale as part of their recommended Standard Set of Stroke Outcome Measures. Before collection of PROMIS GH is broadly implemented, it is necessary to assess its performance in the stroke population. The objective of this study was to evaluate the psychometric properties of PROMIS GH in patients with ischemic stroke and intracerebral hemorrhage. PROMIS GH and 6 PROMIS domain scales measuring same/similar constructs were electronically collected on 1102 patients with ischemic and hemorrhagic strokes at various stages of recovery from their stroke who were seen in a cerebrovascular clinic from October 12, 2015, through June 2, 2017. Confirmatory factor analysis was performed to evaluate the adequacy of 2-factor structure of component scores. Test-retest reliability and convergent validity of PROMIS GH items and component scores were assessed. Discriminant validity and responsiveness were compared between PROMIS GH and PROMIS domain scales measuring the same or related constructs. Analyses were repeated stratified by stroke subtype and modified Rankin Scale score validity was good with significant correlations between all PROMIS GH items and PROMIS domain scales ( P 0.5) was demonstrated for 8 of the 10 PROMIS GH items. Reliability and validity remained consistent across stroke subtype and disability level (modified Rankin Scale, <2 versus ≥2). PROMIS GH exhibits acceptable performance in patients with stroke. Our findings support International Consortium for Health Outcomes Measurement recommendation to use PROMIS GH as part of the standard set of outcome measures in stroke. © 2017 American Heart Association, Inc.

Evaluation of DELTA(1232) components in sup 1 sup 2 C

CERN Document Server

Bystritsky, V M; Krechetov, Yu F; Saigushkin, O K; Tabachenko, A N; Schuvalov, E N; Grabmayr, R; Fiks, A I

2001-01-01

One measured cross section of sup 1 sup 2 C(gamma, pi sup + p) reaction within DELTA(1232)-isobar range. Data analysis was carried out using model taking account of both nucleon and isobar degrees of freedom of sup 1 sup 2 C nucleus. One makes a conclusion that within high transmitted pulses pi sup + p-pairs are formed during DELTA sup + sup + -isobar direct knocking-out of a nucleus. One estimated the probability to determine DELTA-isobar in sup 1 sup 2 C nucleus ground state equal to 0.018 +- 0.005 DELTA-isobar per nucleon

IGF-I bioactivity might reflect different aspects of quality of life than total IGF-I in gh-deficient patients during GH treatment

NARCIS (Netherlands)

A.J. Varewijck (Aimee); S.W.J. Lamberts (Steven); S.J.C.M.M. Neggers (Bas); L.J. Hofland (Leo); J.A.M.J.L. Janssen (Joseph)

2013-01-01

textabstractContext: No relationship has been found between improvement in quality of life (QOL) and total IGF-I during GH therapy. Aim: Our aim was to investigate the relationship between IGF-I bioactivity and QOL in GH-deficient (GHD) patients receiving GH for 12 months. Methods: Of 106 GHD

Structural and superconducting properties of (Y,Gd)Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} grown by MOCVD on samarium zirconate buffered IBAD-MgO

Energy Technology Data Exchange (ETDEWEB)

Stan, L; Holesinger, T G; Maiorov, B; Feldmann, D M; Usov, I O; DePaula, R F; Civale, L; Foltyn, S R; Jia, Q X [Los Alamos National Laboratory, PO Box 1663, Los Alamos, NM 87545 (United States); Chen, Y; Selvamanickam, V [SuperPower, Incorporated, 450 Duane Avenue, Schenectady, NY 12304 (United States)

2008-10-01

Textured samarium zirconate (SZO) films have been grown by reactive cosputtering directly on an ion beam assisted deposited (IBAD) MgO template, without an intermediate homoepitaxial MgO layer. The subsequent growth of 0.9 {mu}m thick (Y,Gd)Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} ((Y, Gd)BCO) films by metal organic chemical vapor deposition (MOCVD) yielded well textured films with a full width at half maximum of 1.9{sup 0} and 3.4{sup 0} for the out-of-plane and in-plane texture, respectively. Microstructural characterizations of the SZO buffered samples revealed clean interfaces. This indicates that the SZO not only provides a diffusion barrier, but also functions as a buffer for (Y, Gd)BCO grown by MOCVD. The achievement of self-field critical current densities (J{sub c}) of over 2 MA cm{sup -2} at 75.5 K is another proof of the effectiveness of SZO as a buffer on the IBAD-MgO template. The in-field measurements revealed an asymmetric angular dependence of J{sub c} and a shift of the ab-plane maxima due to the tilted nature of the template and (Y,Gd){sub 2}O{sub 3} particles existing in the (Y, Gd)BCO matrix. The present results are especially important because they demonstrate that high temperature superconducting coated conductors with simpler architecture can be fabricated using commercially viable processes.

In Situ Forming and H2O2-Releasing Hydrogels for Treatment of Drug-Resistant Bacterial Infections.

Science.gov (United States)

Lee, Yunki; Choi, Kyong-Hoon; Park, Kyung Min; Lee, Jong-Min; Park, Bong Joo; Park, Ki Dong

2017-05-24

Various types of commercialized wound dressings (e.g., films, foams, gels, and nanofiber meshes) have been clinically used as a physical barrier against bacterial invasion and as wound-healing materials. Although these dressings can protect the wounded tissue from the external environment, they cannot treat the wounds that are already infected with bacteria. Herein, we report in situ H 2 O 2 -releasing hydrogels as an active wound dressing with antibacterial properties for treatment of drug-resistant bacterial infection. In this study, H 2 O 2 was used for two major purposes: (1) in situ gel formation via a horseradish peroxidase (HRP)/H 2 O 2 -triggered cross-linking reaction, and (2) antibacterial activity of the hydrogel via its oxidative effects. We found that there were residual H 2 O 2 in the matrix after in situ HRP-catalyzed gelling, and varying the feed amount of H 2 O 2 (1-10 mM; used to make hydrogels) enabled control of H 2 O 2 release kinetics within a range of 2-509 μM. In addition, although the gelatin-hydroxyphenyl propionic acid (GH) gel called "GH 10" (showing the greatest H 2 O 2 release, 509 μM) slightly decreased cell viability (to 82-84%) of keratinocyte (HaCaT) and fibroblast (L-929) cells in in vitro assays, none of the hydrogels showed significant cytotoxicity toward tissues in in vivo skin irritation tests. When the H 2 O 2 -releasing hydrogels that promote in vivo wound healing, were applied to various bacterial strains in vitro and ex vivo, they showed strong killing efficiency toward Gram-positive bacteria including Staphylococcus aureus, S. epidermidis, and clinical isolate of methicillin-resistant S. aureus (MRSA, drug-resistant bacteria), where the antimicrobial effect was dependent on the concentration of the H 2 O 2 released. The present study suggests that our hydrogels have great potential as an injectable/sprayable antimicrobial dressing with biocompatibility and antibacterial activity against drug-resistant bacteria including

Ab initio study of thermoelectric properties of doped SnO{sub 2} superlattices

Energy Technology Data Exchange (ETDEWEB)

Borges, P.D., E-mail: pdborges@gmail.com [Instituto de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, 38810-000 Rio Paranaíba, MG (Brazil); Silva, D.E.S.; Castro, N.S.; Ferreira, C.R.; Pinto, F.G.; Tronto, J. [Instituto de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, 38810-000 Rio Paranaíba, MG (Brazil); Scolfaro, L. [Department of Physics, Texas State University, 78666 San Marcos, TX (United States)

2015-11-15

Transparent conductive oxides, such as tin dioxide (SnO{sub 2}), have recently shown to be promising materials for thermoelectric applications. In this work we studied the thermoelectric properties of Fe-, Sb- and Zn-uniformly doping and co-doping SnO{sub 2}, as well as of Sb and Zn planar (or delta)-doped layers in SnO{sub 2} forming oxide superlattices (SLs). Based on the semiclassical Boltzmann transport equations (BTE) in conjunction with ab initio electronic structure calculations, the Seebeck coefficient (S) and figure of merit (ZT) are obtained for these systems, and are compared with available experimental data. The delta doping approach introduces a remarkable modification in the electronic structure of tin dioxide, when compared with the uniform doping, and colossal values for ZT are predicted for the delta-doped oxide SLs. This result is a consequence of the two-dimensional electronic confinement and the strong anisotropy introduced by the doped planes. In comparison with the uniformly doped systems, our predictions reveal a promising use of delta-doped SnO{sub 2} SLs for enhanced S and ZT, which emerge as potential candidates for thermoelectric applications. - Graphical abstract: Band structure and Figure of merit for SnO2:Sb superlattice along Z direction, P. D. Borges, D. E. S. Silva, N. S. Castro, C. R. Ferreira, F. G. Pinto, J. Tronto and L. Scolfaro, Ab initio study of thermoelectric properties of doped SnO2 superlattices. - Highlights: • Thermoelectric properties of SnO{sub 2}-based alloys and superlattices. • High figure of merit is predicted for planar-doped SnO{sub 2} superlattices. • Nanotechnology has an important role for the development of thermoelectric devices.

The GH/IGF-1 axis in ageing and longevity

Science.gov (United States)

List, Edward O.; Berryman, Darlene E.; Murrey, John W.

2014-01-01

Secretion of growth hormone (GH), and consequently that of insulin-like growth factor 1 (IGF-1), declines over time until only low levels can be detected in individuals aged ≥60 years. This phenomenon, which is known as the ‘somatopause’, has led to recombinant human GH being widely promoted and abused as an antiageing drug, despite lack of evidence of efficacy. By contrast, several mutations that decrease the tone of the GH/IGF-1 axis are associated with extended longevity in mice. In humans, corresponding or similar mutations have been identified, but whether these mutations alter longevity has yet to be established. The powerful effect of reduced GH activity on lifespan extension in mice has generated the hypothesis that pharmaceutically inhibiting, rather than increasing, GH action might delay ageing. Moreover, mice as well as humans with reduced activity of the GH/IGF-1 axis are protected from cancer and diabetes mellitus, two major ageing-related morbidities. Here, we review data on mouse strains with alterations in the GH/IGF-1 axis and their effects on lifespan. The outcome of corresponding or similar mutations in humans is described, as well as the potential mechanisms underlying increased longevity and the therapeutic benefits and risks of medical disruption of the GH/IGF-1 axis in humans. PMID:23591370

Indução de resistência sistêmica à antracnose em feijoeiro-comum pela raça delta avirulenta de Colletotrichum lindemuthianum Induction of systemic resistance to anthracnose in common bean by the avirulent delta race of Colletotrichum lindemuthianum

Directory of Open Access Journals (Sweden)

Ângela Diniz Campos

2009-01-01

Full Text Available O objetivo deste trabalho foi avaliar o potencial da raça delta avirulenta do fungo Colletotrichum lindemuthianum, como protetora contra raças virulentas deste fungo e quanto à capacidade de induzir resistência sistêmica em feijoeiro-comum (Phaseolus vulgaris. Quatro cultivares de feijoeiro foram avaliadas quanto às alterações nas atividades de beta 1,3 glucanase e quitinase, em dois estádios de desenvolvimento (V2 e R6, três dias após a aplicação de suspensão de esporos de C. lindemuthianum raça delta avirulenta, em comparação com aplicações de água e ácido salicílico. As plantas foram, então, infectadas com o patótipo virulento 33/95 de C. lindemuthianum em suspensão e, depois de cinco dias, foram reavaliadas quanto à atividade das enzimas. Observaram-se acréscimos significativos nas atividades da beta 1,3 glucanase e quitinase, após inoculação do fungo indutivo, nas duas avaliações, nos dois estádios de desenvolvimento. As atividades da beta 1,3 glucanase e da quitinase variaram entre as cultivares e entre os estádios de desenvolvimento das plantas. A correlação entre o índice de severidade da doen��a e a atividade das enzimas foi altamente significativa. O uso de C. lindemuthianum raça delta avirulenta diminuiu a severidade da doença e pode ter potencial para controlar a antracnose do feijoeiro.The objectives of this work were to evaluate the potential of the avirulent delta race of Colletotrichum lindemuthianum as a protector against virulent races of this fungus and induce systemic resistance to anthracnose in common bean (Phaseolus vulgaris. Four common bean cultivars were evaluated for changes in the activities of beta-1,3-glucanase and chitinase at two common bean developmental stages, V2 and R6, three days after the infection with delta race of C. lindemuthianum, in comparison with control applications of water and salicylic acid. The plants were then infected with a spore suspension of 33

Examination of Growth Hormone (GH) Gene Polymorphism and its Association with Body Weight and Selected Body Dimensions in Ducks.

Science.gov (United States)

Mazurowski, Artur; Frieske, Anna; Kokoszynski, Dariusz; Mroczkowski, Sławomir; Bernacki, Zenon; Wilkanowska, Anna

2015-01-01

The main objective of the study was to assess the polymorphism in intron 2 of the GH gene and its association with some morphological traits (body weight--BW, length of trunk with neck--LTN, length of trunk--LT, chest girth--CG, length of breast bone--LBB, length of shank--LS). Polymorphism in intron 2 of the GH gene was evaluated for four duck populations (Pekin ducks AF51, Muscovy ducks from a CK and CRAMMLCFF mother and Mulard ducks). Genetic polymorphism was determined with the PCR-RFLP method using the BsmFI restriction enzyme. In the studied duck sample two alleles (GH(C) and GH(T)) and three genotypes (GH/TT, GH/CT, GH/CC) were found at locus GH/BsmFI. In both groups of Muscovies and in Mulards the dominant allele was GH(T). On the contrary in Pekin ducks AF51, the frequency of both alleles was found to be similar. The most frequent genotype in the examined ducks was GH/TT. In Pekin ducks AF51 three genotypes were observed, while in Mulard ducks and in male Muscovy ducks from a mother marked as CK, two genotypes (GH/TT and GH/CT) were identified. Muscovy duck females from a CK mother and all males and females of Muscovy duck from a CRAMMLCFF mother were monomorphic with only the GH/TTgenotype detected. The results showed that males of Pekin duck AF51 with the GH/TT genotype were characterized by higher (P ducks AF51, this same trend was observed; individuals with GH/TT genotype were superior (P ducks with the GH/TT genotype were distinguished by higher values of all evaluated traits compared to ducks with GH/CT and GH/CC genotypes, however most of the recorded differences were not significant. The only trait markedly impacted (P < 0.05) by the polymorphism of the GH gene intron 2 was the LS value in males.

Spanish genetic admixture is associated with larger V(O2) max decrement from sea level to 4338 m in Peruvian Quechua.

Science.gov (United States)

Brutsaert, Tom D; Parra, Esteban J; Shriver, Mark D; Gamboa, Alfredo; Palacios, Jose-Antonio; Rivera, Maria; Rodriguez, Ivette; León-Velarde, Fabiola

2003-08-01

Quechua in the Andes may be genetically adapted to altitude and able to resist decrements in maximal O2 consumption in hypoxia (DeltaVo2 max). This hypothesis was tested via repeated measures of Vo2 max (sea level vs. 4338 m) in 30 men of mixed Spanish and Quechua origins. Individual genetic admixture level (%Spanish ancestry) was estimated by using ancestry-informative DNA markers. Genetic admixture explained a significant proportion of the variability in DeltaVo2 max after control for covariate effects, including sea level Vo2 max and the decrement in arterial O2 saturation measured at Vo2 max (DeltaSpO2 max) (R2 for admixture and covariate effects approximately 0.80). The genetic effect reflected a main effect of admixture on DeltaVo2 max (P = 0.041) and an interaction between admixture and DeltaSpO2 max (P = 0.018). Admixture predicted DeltaVo2 max only in subjects with a large DeltaSpO2 max (P = 0.031). In such subjects, DeltaVo2 max was 12-18% larger in a subgroup of subjects with high vs. low Spanish ancestry, with least squares mean values (+/-SE) of 739 +/- 71 vs. 606 +/- 68 ml/min, respectively. A trend for interaction (P = 0.095) was also noted between admixture and the decrease in ventilatory threshold at 4338 m. As previously, admixture predicted DeltaVo2 max only in subjects with a large decrease in ventilatory threshold. These findings suggest that the genetic effect on DeltaVo2 max depends on a subject's aerobic fitness. Genetic effects may be more important (or easier to detect) in athletic subjects who are more likely to show gas-exchange impairment during exercise. The results of this study are consistent with the evolutionary hypothesis and point to a better gas-exchange system in Quechua.

Management of endocrine disease: GH excess: diagnosis and medical therapy

DEFF Research Database (Denmark)

Andersen, Marianne

2014-01-01

Acromegaly is predominantly caused by a pituitary adenoma, which secretes an excess of GH resulting in increased IGF-I levels. Most of the GH assays used currently measure only the 22 kDa form of GH. In theory, the diagnostic sensitivity may be lower compared to the previous assays, which used...... polyclonal antibodies. Many GH-secreting adenomas are plurihormonal and may co-secrete prolactin, TSH and α-subunit. Hyperprolactinemia is found in 30-40% of patients with acromegaly and hyperprolactinemia may occasionally be diagnosed before acromegaly is apparent.Although trans-sphenoidal surgery of a GH......-secreting adenoma remains the first treatment at most centres, the role of somatostatin analogues, octreotide LAR and lanreotide Autogel, as primary therapy is still the subject of some debate. While normalization of GH and IGF-I levels is the main objective in all patients with acromegaly, GH and IGF-I levels may...

Requirement of tyrosine residues 333 and 338 of the growth hormone (GH) receptor for selected GH-stimulated function

DEFF Research Database (Denmark)

Lobie, P E; Allevato, G; Norstedt, G

1995-01-01

We have examined the involvement of tyrosine residues 333 and 338 of the growth hormone (GH) receptor in the cellular response to GH. Stable Chinese hamster ovary (CHO) cell clones expressing a receptor with tyrosine residues at position 333 and 338 of the receptor substituted for phenylalanine (...

Baseline characteristics and response to 2 years of growth hormone (GH) replacement of hypopituitary patients with GH deficiency due to adult-onset craniopharyngioma in comparison with patients with nonfunctioning pituitary adenoma: data from KIMS (Pfizer International Metabolic Database).

Science.gov (United States)

Verhelst, Johan; Kendall-Taylor, Pat; Erfurth, Eva Marie; Price, David Anthony; Geffner, Mitchell; Koltowska-Häggström, Maria; Jönsson, Peter J; Wilton, Patrick; Abs, Roger

2005-08-01

In epidemiological studies, hypopituitary adults show increased mortality compared with population controls. Patients with hypopituitarism caused by a craniopharyngioma (CP) and/or its treatment have a higher mortality than patients with other etiologies, such as a nonfunctioning pituitary adenoma (NFPA). To analyze this difference, we used the KIMS database (Pfizer International Metabolic Database) comparing CP and NFPA patients in terms of baseline characteristics and responses to GH replacement. Baseline characteristics were studied in 351 CP patients (189 men and 162 women; mean age, 42.5 yr) and compared with 370 NFPA patients, matched for age and sex (185 men and 185 women; mean age, 42.5 yr). The effects of 2 yr of GH replacement were analyzed in a subgroup of 183 CP and 209 NFPA patients. At baseline, both CP and NFPA patients had characteristic features of GH deficiency, with low serum IGF-I, increased body fat, dyslipidemia, and reduced quality of life. Male CP patients were significantly more obese (30.0 vs. 28.2 kg/m2; P = 0.0003) compared with NFPA patients, had a higher waist/hip ratio (P = 0.004), higher triglycerides (P = 0.003), and lower high-density lipoprotein cholesterol (P = 0.03). Similar, but much smaller, differences were seen in female CP compared with NFPA patients, only reaching significance for waist/hip ratio (P = 0.05) and triglycerides (P = 0.0004). CP patients had more often undergone surgery by the transcranial route (68.8% vs. 30.9%; P NFPA patients (58.7% vs. 19.8%; P NFPA patients. After 2 yr of GH replacement therapy, similar significant improvements were evident in both groups in fat-free mass, total and low-density lipoprotein cholesterol, and Quality-of-Life-Assessment in GH Deficient Adults score compared with baseline. In contrast to NFPA patients, CP patients had no significant decrease in body fat with GH therapy. In the KIMS database, patients with CP have more often undergone surgery by the transcranial route than

A {mu}SR study of the magnetoresistive ruthenocuprates RuSr{sub 2}Nd{sub 1.8-x}Y {sub 0.2}Ce{sub x}Cu{sub 2}O{sub 10-{delta}} (x = 0.95 and 0.80)

Energy Technology Data Exchange (ETDEWEB)

Mclaughlin, A C [Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE (United Kingdom); Attfield, J P [Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, King' s Buildings, Mayfield Road, Edinburgh EH9 3JZ (United Kingdom); Van Duijn, J [Instituto de Investigacion en EnergIas Renovables, Universidad de Castilla la Mancha, Albacete, E02006 (Spain); Hillier, A D, E-mail: a.c.mclaughlin@abdn.ac.uk [ISIS facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom)

2011-09-14

Zero field muon spin relaxation (ZF-{mu}SR) has been used to study the magnetic properties of the underdoped giant magnetoresistive ruthenocuprates RuSr{sub 2}Nd{sub 1.8-x}Y {sub 0.2}Ce{sub x}Cu{sub 2}O{sub 10-{delta}} (x = 0.95, 0.80). The magnetoresistance (MR) is defined so that MR = (({rho}{sub H}-{rho}{sub 0})/{rho}{sub 0}) and the giant magnetoresistive ruthenocuprates RuSr{sub 2}Nd{sub 1.8-x}Y {sub 0.2}Ce{sub x}Cu{sub 2}O{sub 10-{delta}} exhibit a large reduction in electronic resistivity upon application of a magnetic field. The ZF-{mu}SR results show a gradual loss of initial asymmetry A{sub 0} at the ruthenium spin transition temperature, T{sub Ru}. At the same time the electronic relaxation rate, {lambda}, shows a gradual increase with decreasing temperature below T{sub Ru}. These results have been interpreted as evidence for Cu spin cluster formation below T{sub Ru}. These magnetically ordered clusters grow as the temperature is decreased thus causing the initial asymmetry to decrease slowly. Giant magnetoresistance is observed over a wide temperature range in the materials studied and the magnitude increases as the temperature is reduced from T{sub Ru} to 4 K which suggests a relation between Cu spin cluster size and |-MR|. (paper)

Effects of Huang Bai (Phellodendri Cortex and Three Other Herbs on GnRH and GH Levels in GT1–7 and GH3 Cells

Directory of Open Access Journals (Sweden)

Sun Haeng Lee

2016-01-01

Full Text Available The present study was to evaluate the effects of Huang Bai, Zhi Mu, Mai Ya, and Xia Ku Cao on hormone using the GT1–7 and GH3 cells. The GT1–7 and GH3 cell lines were incubated with DW; DMSO; and 30, 100, or 300 μg/mL of one of the four extract solutions in serum-free media for 24 hours. The MTT assay was performed to determine the cytotoxicity of the four herbs. The GT1–7 and GH3 cells were incubated in DW, estradiol (GT1–7 only, or noncytotoxic herb solutions in serum-free medium for 24 hours. A quantitative RT-PCR and western blot were performed to measure the GnRH expression in GT1–7 cells and GH expression in GH3 cells. Huang Bai, Zhi Mu, Xia Ku Cao, and Mai Ya inhibited the GnRH mRNA expression in GT1–7 cells, whereas Huang Bai enhanced GH mRNA expression in GH3 cells. Additionally, Xia Ku Cao inhibited GnRH protein expression in GT1–7 cells and Huang Bai promoted GH protein expression in GH3 cells. The findings suggest that Huang Bai can delay puberty by inhibiting GnRH synthesis in the hypothalamus while also accelerating growth by promoting GH synthesis and secretion in the pituitary.

Antimicrobial peptide GH12 suppresses cariogenic virulence factors of Streptococcus mutans

Science.gov (United States)

Wang, Yufei; Wang, Xiuqing; Jiang, Wentao; Wang, Kun; Luo, Junyuan; Li, Wei; Zhou, Xuedong; Zhang, Linglin

2018-01-01

ABSTRACT Cariogenic virulence factors of Streptococcus mutans include acidogenicity, aciduricity, and extracellular polysaccharides (EPS) synthesis. The de novo designed antimicrobial peptide GH12 has shown bactericidal effects on S. mutans, but its interaction with virulence and regulatory systems of S. mutans remains to be elucidated. The objectives were to investigate the effects of GH12 on virulence factors of S. mutans, and further explore the function mechanisms at enzymatic and transcriptional levels. To avoid decrease in bacterial viability, we limited GH12 to subinhibitory levels. We evaluated effects of GH12 on acidogenicity of S. mutans by pH drop, lactic acid measurement and lactate dehydrogenase (LDH) assay, on aciduricity through survival rate at pH 5.0 and F1F0-ATPase assay, and on EPS synthesis using quantitative measurement, morphology observation, vertical distribution analyses and biomass calculation. Afterwards, we conducted quantitative real-time PCR to acquire the expression profile of related genes. GH12 at 1/2 MIC (4 mg/L) inhibited acid production, survival rate, EPS synthesis, and biofilm formation. The enzymatic activity of LDH and F1F0-ATPase was inhibited, and ldh, gtfBCD, vicR, liaR, and comDE genes were significantly downregulated. In conclusion, GH12 inhibited virulence factors of S. mutans, through reducing the activity of related enzymes, downregulating virulence genes, and inactivating specific regulatory systems. PMID:29503706

Recycling of Oceanic Lithosphere: Water, fO2 and Fe-isotope Constraints

Science.gov (United States)

Bizmis, M.; Peslier, A. H.; McCammon, C. A.; Keshav, S.; Williams, H. M.

2014-01-01

Spinel peridotite and garnet pyroxenite xenoliths from Hawaii provide important clues about the composition of the oceanic lithosphere, and can be used to assess its contribution to mantle heterogeneity upon recycling. The peridotites have lower bulk H2O (approximately 70-114 ppm) than the MORB source, qualitatively consistent with melt depletion. The garnet pyroxenites (high pressure cumulates) have higher H2O (200-460 ppm, up to 550 ppm accounting for phlogopite) and low H2O/Ce ratios (less than 100). The peridotites have relatively light Fe-isotopes (delta Fe -57 = -0.34 to 0.13) that decrease with increasing depletion, while the pyroxenites are significantly heavier (delta Fe-57 up to 0.3). The observed xenolith, as well as MORB and OIB total Fe-isotope variability is larger that can be explained by existing melting models. The high H2O and low H2O/Ce ratios of pyroxenites are similar to estimates of EM-type OIB sources, while their heavy delta Fe-57 are similar to some Society and Cook-Austral basalts. Therefore, recycling of mineralogically enriched oceanic lithosphere (i.e. pyroxenites) may contribute to OIB sources and mantle heterogeneity. The Fe(3+)/Sigma? systematics of these xenoliths also suggest that there might be lateral redox gradients within the lithosphere, between juxtaposed oxidized spinel peridotites (deltaFMQ = -0.7 to 1.6, at 15 kb) and more reduced pyroxenites (deltaFMQ = -2 to -0.4, at 20-25kb). Such mineralogically and compositionally imposed fO2 gradients may generate local redox melting due to changes in fluid speciation (e.g. reduced fluids from pyroxenite encountering more oxidized peridotite). Formation of such incipient, small degree melts could further contribute to metasomatic features seen in peridotites, mantle heterogeneity, as well as the low velocity and high electrical conductivity structures near the base of the lithosphere and upper mantle.

Sex steroids and the GH axis: Implications for the management of hypopituitarism.

Science.gov (United States)

Birzniece, Vita; Ho, Ken K Y

2017-02-01

Growth hormone (GH) regulates somatic growth, substrate metabolism and body composition. Sex hormones exert profound effect on the secretion and action of GH. Estrogens stimulate the secretion of GH, but inhibit the action of GH on the liver, an effect that occurs when administered orally. Estrogens suppress GH receptor signaling by stimulating the expression proteins that inhibit cytokine receptor signaling. This effect of estrogens is avoided when physiological doses of estrogens are administered via a non-oral route. Estrogen-like compounds, such as selective estrogen receptor modulators, possess dual properties of inhibiting the secretion as well as the action of GH. In contrast, androgens stimulate GH secretion, driving IGF-1 production. In the periphery, androgens enhance the action of GH. The differential effects of estrogens and androgens influence the dose of GH replacement in patients with hypopituitarism on concomitant treatment with sex steroids. Where possible, a non-oral route of estrogen replacement is recommended for optimizing cost-benefit of GH replacement in women with GH deficiency. Adequate androgen replacement in conjunction with GH replacement is required to achieve the full anabolic effect in men with hypopituitarism. Copyright © 2017 Elsevier Ltd. All rights reserved.

Structure of the GH1 domain of guanylate kinase-associated protein from Rattus norvegicus

International Nuclear Information System (INIS)

Tong, Junsen; Yang, Huiseon; Eom, Soo Hyun; Chun, ChangJu; Im, Young Jun

2014-01-01

Graphical abstract: - Highlights: • The crystal structure of GKAP homology domain 1 (GH1) was determined. • GKAP GH1 is a three-helix bundle connected by short flexible loops. • The predicted helix α4 associates weakly with the helix α3, suggesting dynamic nature of the GH1 domain. - Abstract: Guanylate-kinase-associated protein (GKAP) is a scaffolding protein that links NMDA receptor-PSD-95 to Shank–Homer complexes by protein–protein interactions at the synaptic junction. GKAP family proteins are characterized by the presence of a C-terminal conserved GKAP homology domain 1 (GH1) of unknown structure and function. In this study, crystal structure of the GH1 domain of GKAP from Rattus norvegicus was determined in fusion with an N-terminal maltose-binding protein at 2.0 Å resolution. The structure of GKAP GH1 displays a three-helix bundle connected by short flexible loops. The predicted helix α4 which was not visible in the crystal structure associates weakly with the helix α3 suggesting dynamic nature of the GH1 domain. The strict conservation of GH1 domain across GKAP family members and the lack of a catalytic active site required for enzyme activity imply that the GH1 domain might serve as a protein–protein interaction module for the synaptic protein clustering

Structure of the GH1 domain of guanylate kinase-associated protein from Rattus norvegicus

Energy Technology Data Exchange (ETDEWEB)

Tong, Junsen; Yang, Huiseon [College of Pharmacy, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Eom, Soo Hyun [School of Life Sciences, Steitz Center for Structural Biology, and Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Chun, ChangJu, E-mail: cchun1130@jnu.ac.kr [College of Pharmacy, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Im, Young Jun, E-mail: imyoungjun@jnu.ac.kr [College of Pharmacy, Chonnam National University, Gwangju 500-757 (Korea, Republic of)

2014-09-12

Graphical abstract: - Highlights: • The crystal structure of GKAP homology domain 1 (GH1) was determined. • GKAP GH1 is a three-helix bundle connected by short flexible loops. • The predicted helix α4 associates weakly with the helix α3, suggesting dynamic nature of the GH1 domain. - Abstract: Guanylate-kinase-associated protein (GKAP) is a scaffolding protein that links NMDA receptor-PSD-95 to Shank–Homer complexes by protein–protein interactions at the synaptic junction. GKAP family proteins are characterized by the presence of a C-terminal conserved GKAP homology domain 1 (GH1) of unknown structure and function. In this study, crystal structure of the GH1 domain of GKAP from Rattus norvegicus was determined in fusion with an N-terminal maltose-binding protein at 2.0 Å resolution. The structure of GKAP GH1 displays a three-helix bundle connected by short flexible loops. The predicted helix α4 which was not visible in the crystal structure associates weakly with the helix α3 suggesting dynamic nature of the GH1 domain. The strict conservation of GH1 domain across GKAP family members and the lack of a catalytic active site required for enzyme activity imply that the GH1 domain might serve as a protein–protein interaction module for the synaptic protein clustering.

Desenvolvimento da ferrita delta na solda e ZTA resultante de soldagem plasma pulsada em um aço inoxidável supermartensítico Delta-ferrite development in weld and HAZ produced by pulsed plasma arc welding in a supermartensitic stainless steel

Directory of Open Access Journals (Sweden)

Sérgio L. Henke

2013-03-01

Full Text Available A ferrita delta é considerada uma fase indesejável na microestrutura dos aços inoxidáveis martensíticos haja vista a mesma poder influenciar no desempenho da resistência à fadiga, tenacidade e corrosão sob-tensão. Sendo assim, o objetivo deste trabalho foi investigar o efeito da soldagem plasma pulsada sobre a distribuição e quantidade de ferrita delta em um aço inoxidável supermartensítico. Para tal foram obtidos cordões por meio de fusão superficial sobre uma amostra de aço inoxidável supermartensítico de alta liga utilizando corrente pulsada e convencional. Em seguida foi efetuada a caracterização microestrutural, em especial da ferrita delta, via análises metalográficas por meio de microscopia óptica e eletrônica de varredura . Os experimentos revelaram que, para o mesmo aporte térmico, a pulsação de corrente promoveu a formação de ferrita delta na forma de bandas ao longo do cordão de solda e redução significativa desta fase na ZTA quando comparada à soldagem convencional.The objective of this study was to investigate the effect of pulsed plasma welding on the distribution and amount of delta ferrite which is considered an undesirable phase in a supermartensitic stainless steel. For such weld beads have been obtained by melting the surface of a sample of a high-alloy supermartensitic stainless steel using pulsed and conventional current. Microstructural characterization, especially of delta ferrite, was performed by metallographic analysis by means of optical microscopy and scanning electron microscopy. The experiments showed that for the same heat input, pulsed current promoted the formation of delta ferrite in the form of bands along the weld bead and caused a significant reduction of this phase in HAZ as compared to conventional welding.

Effects of polybrominated diphenyl ethers (PBDEs) and their derivatives on protein disulfide isomerase activity and growth hormone release of GH3 cells.

Science.gov (United States)

Hashimoto, Shoko; Yoshimura, Hiromi; Okada, Kazushi; Uramaru, Naoto; Sugihara, Kazumi; Kitamura, Shigeyuki; Imaoka, Susumu

2012-03-19

Polybrominated diphenyl ethers (PBDEs) have been used in a variety of consumer products such as flame retardants and recently have been known to be widespread environmental pollutants, which probably affect biological functions of mammalian cells. However, the risk posed by PBDE metabolites has not been clarified. Our previous study suggested that bisphenol A (BPA), an endocrine-disrupting chemical, binds to protein disulfide isomerase (PDI) and inhibits its activity. PDI is an isomerase enzyme in the endoplasmic reticulum and facilitates the formation or cleavage of disulfide bonds. PDI consists of a, b, b', and a' domains and the c region, with the a and a' domains having isomerase active sites. In the present study, we tested the effects of 10 kinds of PBDE compounds and their metabolites on PDI. OH-PBDEs specifically inhibited the isomerase activity of PDI, with 4'-OH-PBDE more effective than 2' (or 2)-OH-PBDEs. 4'-OH-PBDE inhibited the isomerase activity of the b'a'c fragment but not that of ab and a'c, suggesting that the b' domain of PDI is essential for the inhibition by 4'-OH-PBDE. We also investigated the effects of these chemicals on the production of growth hormone (GH) in GH3 cells. In GH3 cells, levels of mRNA and protein of GH stimulated by T(3) were reduced by 4'-OH-PBDE and 4'-MeO-PBDE. The reduction in GH expression caused by these compounds was not changed by the overexpression or knockdown of PDI in GH3 cells, while these manipulations of PDI levels significantly suppressed the expression of GH. These results suggest that the biological effects of PBDEs differed depending on their brominated and hydroxylated positions. © 2011 American Chemical Society

Expression of Lymphocyte-derived Growth Hormone (GH) and GH-releasing Hormone Receptors in Aging Rats

OpenAIRE

Weigent, Douglas A.

2013-01-01

In the present study, we show that higher levels of lymphocyte GH are expressed in spleen cells from aging animals compared to young animals. Further, leukocytes from primary and secondary immune tissues and splenic T and B cells from aging rats all express higher levels of GHRH receptors compared to younger animals. Bone marrow and splenic T cells express the highest levels of GHRH receptor in aging animals. Spleen cells from aging animals showed no significant change in proliferation or GH ...

Coexistence of superconductivity and magnetism in Er{sub 2}Ba{sub 4}Cu{sub 7}O{sub 14.3}

Energy Technology Data Exchange (ETDEWEB)

Mesot, J; Boettger, G; Fischer, P [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suard, E [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France); Berastegui, P

1997-09-01

The Er{sub 2}Ba{sub 4}Cu{sub 7}O{sub 14+{delta}} compounds show a very interesting behaviour upon removing of oxygen. Although the samples remain superconducting when going from {delta}=1 to {delta}=0, our low temperature elastic and inelastic measurements ({delta}<14.3) strongly indicate that a magnetic field is present at the Er site. Such a field could be generated by magnetically active Cu atoms in one of the neighbouring CuO{sub 2} planes. (author) 3 figs., 2 refs.

Bioavailability and bioactivity of three different doses of nasal growth hormone (GH) administered to GH-deficient patients

DEFF Research Database (Denmark)

Laursen, Torben; Grandjean, Birgitte; Jørgensen, Jens Otto Lunde

1996-01-01

different occasions. On three occasions GH was administered intranasally in doses of 0.05, 0.10 and 0.20 IU/kg, using didecanoyl-L-alpha-phosphatidylcholine as an enhancer. On the other two occasions the patients received an sc injection (0.10 IU/kg) and an i.v. injection (0.015 IU/kg) of GH, respectively....... The absolute bioavailability of GH following s.c. relative to i.v. administration was 49.5%. The bioavailabilities of the nasal doses were: 7.8% (0.05 IU). 8.9% (0.10 IU) and 3.8% (0.20 IU). Serum insulin-like growth factor I (IGF-I) levels increased significantly after s.c. administration only. Mean levels...... of the i.v. (p insulin and blood glucose (p

Cerebral desaturation during exercise reversed by O2 supplementation

DEFF Research Database (Denmark)

Nielsen, H B; Boushel, Robert Christopher; Madsen, P

1999-01-01

microM) and DeltaHbO2 (-12 +/- 3 microM) were similar to those established without O2 supplementation, work capacity increased from 389 +/- 11 to 413 +/- 10 W (P cerebral......The combined effects of hyperventilation and arterial desaturation on cerebral oxygenation (ScO2) were determined using near-infrared spectroscopy. Eleven competitive oarsmen were evaluated during a 6-min maximal ergometer row. The study was randomized in a double-blind fashion with an inspired O2...

Stimulation of accumbal GABAA receptors inhibits delta2-, but not delta1-, opioid receptor-mediated dopamine efflux in the nucleus accumbens of freely moving rats.

Science.gov (United States)

Aono, Yuri; Kiguchi, Yuri; Watanabe, Yuriko; Waddington, John L; Saigusa, Tadashi

2017-11-15

The nucleus accumbens contains delta-opioid receptors that may reduce inhibitory neurotransmission. Reduction in GABA A receptor-mediated inhibition of accumbal dopamine release due to delta-opioid receptor activation should be suppressed by stimulating accumbal GABA A receptors. As delta-opioid receptors are divided into delta2- and delta1-opioid receptors, we analysed the effects of the GABA A receptor agonist muscimol on delta2- and delta1-opioid receptor-mediated accumbal dopamine efflux in freely moving rats using in vivo microdialysis. Drugs were administered intracerebrally through the dialysis probe. Doses of compounds indicate total amount administered (mol) during 25-50min infusions. The delta2-opioid receptor agonist deltorphin II (25.0nmol)- and delta1-opioid receptor agonist DPDPE (5.0nmol)-induced increases in dopamine efflux were inhibited by the delta2-opioid receptor antagonist naltriben (1.5nmol) and the delta1-opioid receptor antagonist BNTX (150.0pmol), respectively. Muscimol (250.0pmol) inhibited deltorphin II (25.0nmol)-induced dopamine efflux. The GABA A receptor antagonist bicuculline (50.0pmol), which failed to affect deltorphin II (25.0nmol)-induced dopamine efflux, counteracted the inhibitory effect of muscimol on deltorphin II-induced dopamine efflux. Neither muscimol (250.0pmol) nor bicuculline (50.0 and 500.0pmol) altered DPDPE (5.0nmol)-induced dopamine efflux. The present results show that reduction in accumbal GABA A receptor-mediated inhibition of dopaminergic activity is necessary to produce delta2-opioid receptor-induced increase in accumbal dopamine efflux. This study indicates that activation of delta2- but not delta1-opioid receptors on the cell bodies and/or terminals of accumbal GABAergic interneurons inhibits GABA release and, accordingly, decreases GABA A receptor-mediated inhibition of dopaminergic terminals, resulting in enhanced accumbal dopamine efflux. Copyright © 2017 Elsevier B.V. All rights reserved.

Growth hormone (GH) differentially regulates NF-kB activity in preadipocytes and macrophages: implications for GH's role in adipose tissue homeostasis in obesity.

Science.gov (United States)

Kumar, P Anil; Chitra, P Swathi; Lu, Chunxia; Sobhanaditya, J; Menon, Ram

2014-06-01

Adipose tissue remodeling in obesity involves macrophage infiltration and chronic inflammation. NF-kB-mediated chronic inflammation of the adipose tissue is directly implicated in obesity-associated insulin resistance. We have investigated the effect of growth hormone (GH) on NF-kB activity in preadipocytes (3T3-F442A) and macrophages (J774A.1). Our studies indicate that whereas GH increases NF-kB activity in preadipocytes, it decreases NF-kB activity in macrophages. This differential response of NF-kB activity to GH correlates with the GH-dependent expression of a cadre of NF-kB-activated cytokines in these two cell types. Activation of NF-kB by GH in preadipocytes heightens inflammatory response by stimulating production of multiple cytokines including TNF-α, IL-6, and MCP-1, the mediators of both local and systemic insulin resistance and chemokines that recruit macrophages. Our studies also suggest differential regulation of miR132 and SIRT1 expression as a mechanism underlying the observed variance in GH-dependent NF-kB activity and altered cytokine profile in preadipocytes and macrophages. These findings further our understanding of the complex actions of GH on adipocytes and insulin sensitivity.

Cooper pair formation dynamics in Bi2Sr2CaCu2O8+δ

International Nuclear Information System (INIS)

Kaindl, R.A.; Carnahan, M.A.; Orenstein, J.; Chemla, D.S.; Oh, S.; Eckstein, J.N.

2003-01-01

We utilize ultrafast terahertz pulses to monitor the carrier dynamics in the high-TC superconductor Bi2Sr2CaCu2O8+delta. The temperature, density and time dependence distinctly exposes a bimolecular recombination process of quasiparticles which underlies formation of Cooper pairs

Growth hormone dose regimens in adult GH deficiency: effects on biochemical growth markers and metabolic parameters

DEFF Research Database (Denmark)

Møller, Jens; Jørgensen, Jens Otto Lunde; Laursen, Torben

1993-01-01

Abstract OBJECTIVE: We examined the effects of different doses of GH on insulin-like growth factor I (IGF-I), IGF binding protein 3 (IGFBP-3), body composition, energy expenditure, and various metabolites in GH deficient adults, in order to approach a metabolically appropriate GH dosage in young GH......-I in an age and sex matched control group was 248 +/- 25 micrograms/l. Corresponding serum IGFBP-3 levels also increased from 1860 +/- 239 to 3261 +/- 379, 3762 +/- 434 and 4384 +/- 652 micrograms/l (P = 0.01) respectively. Significant increases in diurnal serum insulin levels after 4 IU/m2 were recorded......, whereas plasma glucose levels remained unchanged. Lipid intermediates increased dose independently during GH administration. GH caused a significant increase in resting energy expenditure, whereas the respiratory exchange ratio was unaltered. Fat mass was increased without GH therapy and decreased during...

Do IGF-I concentrations better reflect growth hormone (GH action in children with short stature than the results of GH stimulating tests? Evidence from the simultaneous assessment of thyroid function

Directory of Open Access Journals (Sweden)

Smyczyńska Joanna

2011-01-01

Full Text Available Abstract Background The diagnosis of growth hormone (GH deficiency (GHD in short children seems unquestionable when both GH peak in stimulating tests (GHST and IGF-I concentration are decreased. However, the discrepancies between the results of GHST and IGF-I secretion are observed. It seems purposeful to determine the significance of GHST and IGF-I assessment in diagnosing GHD. The relationship between GH secretion and thyroid function, as well as GH influence on the peripheral thyroxine (T4 to triiodothyronine (T3 deiodination, mediated by IGF-I, were identified. Thus, clear differences in thyroid function between GH-deficient and non-GH-deficient subjects should exist. Methods Analysis comprised 800 children (541 boys, age 11.6 ± 3.1 years (mean ± SD, with short stature, in whom two (2 standard GHST (with clonidine and with glucagon were performed and IGF-I, free T4 (FT4, free T3 (FT3 and TSH serum concentrations were assessed. The patients were qualified to the following groups: GHD - decreased GH peak in GHST and IGF-I SDS (n = 81, ISS - normal GH peak and IGF-I SDS (n = 347, low GH - normal IGF-I SDS, and decreased GH peak (n = 212, low IGF - decreased IGF-I SDS, and normal GH peak (n = 160. The relationships among the results of particular tests were evaluated. Results In the groups with decreased IGF-I concentrations (GHD Group and low IGF Group, the more severe deficit of height was observed, together with higher TSH and FT4 but lower FT3 levels than in groups with normal IGF-I concentrations (ISS Group and low GH Group, independently of the results of GHST. TSH, FT4 and FT3 concentrations were - respectively - similar in two groups with decreased IGF-I secretion, as well as in two groups with normal IGF-I levels. Significant correlations were found between patients' height SDS and IGF-I SDS, between FT3 and IGF-I SDS (positive, and between FT4 and IGF-I SDS (negative, with no correlation between GH peak and any of the parameters

Recurrent intergrowths in the topotactic reduction process of LaBaCuCoO5.2.

Science.gov (United States)

Ruiz-González, Luisa; Boulahya, Khalid; Parras, Marina; Alonso, José; González-Calbet, José M

2002-12-16

A new perovskite-related oxide with the LaBaCuCoO5.2 composition has been stabilised. Its structure can be described as formed by the recurrent intergrowth of two alternating blocks of YBaCuFeO5 (2ac, i.e., two-fold perovskite superlattice) and YBa2Fe3O8 (3ac) structural types. From the starting material LaBaCuCoO5.2-delta (delta = 0), the rigorous control of the oxygen content has allowed the stabilisation of three new five fold perovskite-related superstructures with the compositions delta = 0.4, 0.8 and 1.1, which can also be described as recurrent intergrowths of two blocks showing 2ac and 3ac periodicity. The reduction process takes place through the 3ac periodic blocks, when 0 topotactic reaction, since their basic structure is kept through the reduction process.

MSM enhances GH signaling via the Jak2/STAT5b pathway in osteoblast-like cells and osteoblast differentiation through the activation of STAT5b in MSCs.

Directory of Open Access Journals (Sweden)

Youn Hee Joung

Full Text Available Methylsulfonylmethane (MSM is a naturally occurring sulfur compound with well-known anti-oxidant properties and anti-inflammatory activities. But, its effects on bone are unknown. Growth hormone (GH is regulator of bone growth and bone metabolism. GH activates several signaling pathways such as the Janus kinase (Jak/signal transducers and activators of transcription (STAT pathway, thereby regulating expression of genes including insulin-like growth factor (IGF-1. GH exerts effects both directly and via IGF-1, which signals by activating the IGF-1 receptor (IGF-1R. In this study, we investigated the effects of MSM on the GH signaling via the Jak/STAT pathway in osteoblasts and the differentiation of primary bone marrow mesenchymal stem cells (MSCs. MSM was not toxic to osteoblastic cells and MSCs. MSM increased the expression of GH-related proteins including IGF-1R, p-IGF-1R, STAT5b, p-STAT5b, and Jak2 in osteoblastic cells and MSCs. MSM increased IGF-1R and GHR mRNA expression in osteoblastic cells. The expression of MSM-induced IGF-1R and GHR was inhibited by AG490, a Jak2 kinase inhibitor. MSM induced binding of STAT5 to the IGF-1R and increased IGF-1 and IGF-1R promoter activities. Analysis of cell extracts by immunoprecipitation and Western blot showed that MSM enhanced GH-induced activation of Jak2/STAT5b. We found that MSM and GH, separately or in combination, activated GH signaling via the Jak2/STAT5b pathway in UMR-106 cells. Using siRNA analysis, we found that STAT5b plays an essential role in GH signaling activation in C3H10T1/2 cells. Osteogenic marker genes (ALP, ON, OCN, BSP, OSX, and Runx2 were activated by MSM, and siRNA-mediated STAT5b knockdown inhibited MSM-induced expression of osteogenic markers. Furthermore, MSM increased ALP activity and the mineralization of MSCs. Taken together, these results indicated that MSM can promote osteogenic differentiation of MSCs through activation of STAT5b.

Clinical features of GH deficiency and effects of 3 years of GH replacement in adults with controlled Cushing's disease

DEFF Research Database (Denmark)

Höybye, Charlotte; Ragnarsson, Oskar; Jönsson, Peter J

2010-01-01

Patients in remission from Cushing's disease (CD) have many clinical features that are difficult to distinguish from those of concomitant GH deficiency (GHD). In this study, we evaluated the features of GHD in a large cohort of controlled CD patients, and assessed the effect of GH treatment....

Substrate Metabolism and Insulin Sensitivity During Fasting in Obese Human Subjects: Impact of GH Blockade.

Science.gov (United States)

Pedersen, Morten Høgild; Svart, Mads Vandsted; Lebeck, Janne; Bidlingmaier, Martin; Stødkilde-Jørgensen, Hans; Pedersen, Steen Bønløkke; Møller, Niels; Jessen, Niels; Jørgensen, Jens O L

2017-04-01

Insulin resistance and metabolic inflexibility are features of obesity and are amplified by fasting. Growth hormone (GH) secretion increases during fasting and GH causes insulin resistance. To study the metabolic effects of GH blockade during fasting in obese subjects. Nine obese males were studied thrice in a randomized design: (1) after an overnight fast (control), (2) after 72 hour fasting (fasting), and (3) after 72 hour fasting with GH blockade (pegvisomant) [fasting plus GH antagonist (GHA)]. Each study day consisted of a 4-hour basal period followed by a 2-hour hyperinsulinemic, euglycemic clamp combined with indirect calorimetry, assessment of glucose and palmitate turnover, and muscle and fat biopsies. GH levels increased with fasting (P fasting-induced reduction of serum insulin-like growth factor I was enhanced by GHA (P Fasting increased lipolysis and lipid oxidation independent of GHA, but fasting plus GHA caused a more pronounced suppression of lipid intermediates in response to hyperinsulinemic, euglycemic clamp. Fasting-induced insulin resistance was abrogated by GHA (P Fasting plus GHA also caused elevated glycerol levels and reduced levels of counterregulatory hormones. Fasting significantly reduced the expression of antilipolytic signals in adipose tissue independent of GHA. Suppression of GH activity during fasting in obese subjects reverses insulin resistance and amplifies insulin-stimulated suppression of lipid intermediates, indicating that GH is an important regulator of substrate metabolism, insulin sensitivity, and metabolic flexibility also in obese subjects. Copyright © 2017 by the Endocrine Society

Energy spectrum of CsDy(MoO/sub 4/)/sub 2/ in the vicinity of the structural phase transition

Energy Technology Data Exchange (ETDEWEB)

Khats' ko, E N; Chernyj, A S [AN Ukrainskoj SSR, Kharkov. Fiziko-Tekhnicheskij Inst. Nizkikh Temperatur

1981-08-01

The magnetic susceptibilities of CsDy(MoO/sub 4/)/sub 2/ and CsDy(MoO/sub 4/)/sub 2/+10%Eu/sup 3 +/ were measured in the temperature range 4 to 70 K and the frequency range 200 Hz to 20 MHz. The observed spin-lattice relaxation of the Dy/sup 3 +/ ion is found to be exponential with the relaxation time as a function of temperature tau/sup -1/=A exp (-..delta../kT) with ..delta..=105+-20 and 250+-40 cm/sup -1/ for CsDy(MoO/sub 4/)/sub 2/ in ranges 10-20 K and 20-38 K, respectively, and ..delta..=22.4+-5 cm for C=sDy(MoO/sub 4/)/sub 2/+10%Eu/sup 3 +/. The energies ..delta..105+-20 and 250 -40cm/sup -1/ are suggested to correspond to the first and second excited levels of Dy/sup 3 +/ in the low temperature phase of CsDy(MoO/sub 4/)/sub 2/, and ..delta..=22.4+-5 cm/sup -1/ to the first excited level of Dy/sup 3 +/ in the high temperature phase of the compound.

Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment

CSIR Research Space (South Africa)

Tshabalala, Zamaswazi P

2016-03-01

Full Text Available and Actuators B: Chemical Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment Z.P. Tshabalalaa,b, D.E. Motaunga,∗, G.H. Mhlongoa,∗, O.M. Ntwaeaborwab,∗ a DST/CSIR, National Centre...

Signal transducer and activator of transcription 5 activation is sufficient to drive transcriptional induction of cyclin D2 gene and proliferation of rat pancreatic beta-cells

DEFF Research Database (Denmark)

Friedrichsen, Birgitte N; Richter, Henrijette E; Hansen, Johnny A

2003-01-01

in a time-dependent manner by hGH in INS-1 cells. Inhibition of protein synthesis by coincubation with cycloheximide did not affect the hGH-induced increase of cyclin D2 mRNA levels at 4 h. Expression of a dominant negative STAT5 mutant, STAT5aDelta749, partially inhibited cyclin D2 protein levels. INS-1...... cells transiently transfected with a cyclin D2 promoter-reporter construct revealed a 3- to 5-fold increase of transcriptional activity in response to hGH stimulation. Furthermore, coexpression of a constitutive active STAT5 mutant (either CA-STAT5a or CA-STAT5b) was sufficient to drive transactivation...

Pulmonary O2 transfer during pulsatile and non-pulsatile perfusion.

Science.gov (United States)

Hauge, A; Nicolaysen, G

1980-07-01

The importance of the perfusion pattern for the oxygen transfer has been examined in isolated rabbit lungs perfused with plasma at constant volume inflow. The lungs were ventilated with constant tidal volume and constant end-expiratory pressure. Following a standardized rise in FIO2 the rate of rise in pulmonary venous PO2 (delta PO2/delta t) was measured during alternately pulsatile and non-pulsatile perfusion in normal lungs and in lungs made edematous by elevation of left atrial pressure. In normal lungs there was no difference in delta PO2/delta t when the two modes of perfusion were compared. In edematous lungs delta PO/delta t was statistically higher during pulsatile perfusion, indicating a beneficial effect of flow- and pressure pulsations, e.g. a better distribution of V/Q ratios throughout the lungs. In a separate series of expts. the advancement of a high O2 front through the airways was measured, and the two perfusion patterns compared. Since no difference was found, we suggest that the phenomenon of "cardiogenic gas mixing" in the airways in vivo is a result of a direct action of the heart on the lungs rather than arterial pulsations.

The Brazilian Portuguese version of the Work Productivity and Activity Impairment: General Health (WPAI-GH Questionnaire

Directory of Open Access Journals (Sweden)

Rozana Mesquita Ciconelli

Full Text Available CONTEXT AND OBJECTIVE: It is still difficult to measure work productivity losses caused by health problems. Despite the importance given to this issue over the last few years, most instruments for performing this task are available only in the English language. This study translated the Work Productivity and Activity Impairment _ General Health (WPAI-GH Questionnaire into Brazilian Portuguese, adapted it cross-culturally and evaluated its reliability and validity. DESIGN AND SETTING: Cross-sectional survey to test scale reliability and validity, at São Paulo Hospital and the clinic of the Rheumatology division of Universidade Federal de São Paulo - Escola Paulista de Medicina (Unifesp-EPM. METHODS: Data were obtained from a survey that incorporated the WPAI-GH, short form-36 (SF-36 and some demographic questions. The questionnaires were administered by interview to 100 subjects. RESULTS: Descriptive statistics was used to characterize the subjects. The intraclass correlation coefficient and Cronbach's alpha were used to assess the reliability and internal consistency of the instrument. Intraclass correlation coefficients from 0.79 to 0.90 indicated good reliability. Cronbach's alpha of 0.74 indicated good internal consistency. Pearson's correlation coefficient was used to assess validity. There were significant positive relationships between the WPAI-GH and SF-36. CONCLUSION: The Brazilian Portuguese version of the WPAI-GH is a reliable and valid measurement tool and may be useful for those who seek to measure the impact on productivity of health problems among populations of Brazilian employees.

Correlation of infrared reflectance ratios at 2.3 microns/1.6 micron and 1.1 micron/1.6 micron with delta O-18 values delineating fossil hydrothermal systems in the Idaho batholith

Science.gov (United States)

Gillespie, A. R.; Criss, R. E.

1983-01-01

Reflectance ratios from laboratory spectra and airborne multispectral images are found to be strongly correlated with delta O-18 values of granite rocks in the Idaho batholith. The correlation is largely a result of interactions between hot water and rock, which lowered the delta O-18 values of the rocks and produced secondary hydrous material. Maps of the ratio of reflectivities at 2.3 and 1.6 microns should delineate fossil hydrothermal systems and provide estimates of alteration intensity. However, hydrous minerals produced during deuteric alteration or weathering cannot be unambiguously distinguished in remotely sensed images from the products of propylitic alteration without the use of narrow-band scanners. The reflectivity at 1.6 micron is strongly correlated with rock density and may be useful in distinguishing rock types in granitic terranes.

Luminescence of a new class of UV-blue-emitting phosphors MSi2O2-deltaN2+2/3delta:Ce3+ (M = Ca, Sr, Ba)

NARCIS (Netherlands)

Li, Y.Q.; With, de G.; Hintzen, H.T.J.M.

2005-01-01

The luminescence properties of Ce3+,Na+-codoped MSi2O22dN2+2/3d (M 5 Ca, Sr, Ba) are reported. The undoped and Ce3+,Na+-codoped MSi2O22dN2+2/3d powders were prepared by a solid-state reaction at temperatures between 1300–1400 uC under N2–H2 (10%) atmosphere in the system MO–SiO2–Si3N4 (M 5 Ca, Sr,

The reactions of SO3 with HO2 radical and H2O...HO2 radical complex. Theoretical study on the atmospheric formation of HSO5 and H2SO4.

Science.gov (United States)

Gonzalez, Javier; Torrent-Sucarrat, Miquel; Anglada, Josep M

2010-03-07

The influence of a single water molecule on the gas-phase reactivity of the HO(2) radical has been investigated by studying the reactions of SO(3) with the HO(2) radical and with the H(2)O...HO(2) radical complex. The naked reaction leads to the formation of the HSO(5) radical, with a computed binding energy of 13.81 kcal mol(-1). The reaction with the H(2)O...HO(2) radical complex can give two different products, namely (a) HSO(5) + H(2)O, which has a binding energy that is computed to be 4.76 kcal mol(-1) more stable than the SO(3) + H(2)O...HO(2) reactants (Delta(E + ZPE) at 0K) and an estimated branching ratio of about 34% at 298K and (b) sulfuric acid and the hydroperoxyl radical, which is computed to be 10.51 kcal mol(-1) below the energy of the reactants (Delta(E + ZPE) at 0K), with an estimated branching ratio of about 66% at 298K. The fact that one of the products is H(2)SO(4) may have relevance in the chemistry of the atmosphere. Interestingly, the water molecule acts as a catalyst, [as it occurs in (a)] or as a reactant [as it occurs in (b)]. For a sake of completeness we have also calculated the anharmonic vibrational frequencies for HO(2), HSO(5), the HSO(5)...H(2)O hydrogen bonded complex, H(2)SO(4), and two H(2)SO(4)...H(2)O complexes, in order to help with the possible experimental identification of some of these species.