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SR
Kinds of SR Terms modified by SR Selected AbstractsA simple method to estimate the contribution of biological floc and reactor-solution to mass transfer of oxygen in activated sludge processesBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2005Venkatram Mahendraker Abstract In this study, the mass transfer coefficient of biological floc (KLabf) was estimated from the mass transfer coefficient of the mixed-liquor (KLaf) and the reactor-solution (KLae). The biological floc resistance (BFR) and reactor-solution resistance (SR) were defined as the reciprocal of KLabf and KLae, respectively, by applying the concept of serial-resistance originally presented in two-film theory (Lewis and Whitman (1924) Ind Eng Chem 16:1215,1220). The specific biological floc resistance (SBFR) was defined as biological floc resistance per unit biomass concentration. The data indicated that an activated sludge process yielding low BFR/MLR and BFR/SR tended to produce higher oxygen transfer efficiency. Surprisingly, the reactor-solution posed the same level of resistance as clean water in all experiments, except in a 5-day SRT, non-nitrifying, completely mixed activated sludge (CMAS) process run. Furthermore, SBFR successfully represented biological floc and showed a positive correlation to sludge volume index (SVI). In addition, SBFR/SR and oxygen transfer efficiency (OTEf) followed an exponential relationship for the complete data set. The method of separating the mixed-liquor into biological floc and reactor-solution improved the understanding of oxygen transfer under process conditions, without resorting to intrusive techniques or direct handling of fragile biological floc. © 2005 Wiley Periodicals, Inc. [source] Indirect Raman identification of the proton insertion in the high-temperature [Ba/Sr][Zr/Ti]O3 -modified perovskite protonic conductors,JOURNAL OF RAMAN SPECTROSCOPY, Issue 5 2009Aneta Slodczyk Abstract OH, and H3O+ species in hydrates and simple oxides are rather well characterised from their IR, Raman and inelastic neutron points of view. For the H+ (H2O) species in solid state the variability is well established and assignment remains discussed. The question of the vibrational signature of isolated proton (e.g. the ionic proton, a proton sharing its interaction with more than two acceptors) and its dynamic nature (proton gas, polaron,,) is open. H+ -containing modified perovskites A(Ba,Sr,,) B(Zr,Ce,Ti,,) O3 are potential ceramic membranes for fuel cell and medium temperature water electrolysis (300,800 °C). Comparison studies of the protonated and non-protonated lanthanide/rare earth-modified perovskites of type Ba(Sr)Zr(Ti)O3 as well as Al-modified BaTiO3 show that a broad component centred at 2500 cm,1 is observed after ,proton insertion'. Its intensity is correlated to the protonic species content as well as to the conductivity of the materials. The mixed nature of this feature is discussed: fluorescence related to the dangling bonds, A, B, C bands or new phenomena related to the ionic protons and associated electronic defect. Copyright © 2008 John Wiley & Sons, Ltd. [source] Variable-Temperature Infrared Spectroscopy Studies on the Thermodynamics of CO Adsorption on the Zeolite Ca,YCHEMPHYSCHEM, Issue 12 2008Barbara Bonelli Dr. Abstract Variable temperature FT,IR spectroscopy (in the range of 298,380 K) is used to study the thermodynamics of formation of Ca2+,,,CO carbonyl species upon CO adsorption on the faujasite-type zeolite Ca,Y, and also the (temperature-dependent) isomerization equilibrium between carbonyl and isocarbonyl (Ca2+,,,OC) species. The standard enthalpy and entropy changes involved in formation of the monocarbonyl species resulted to be ,H0=,50.3 (±0.5) kJ,mol,1 and ,S0=,186 (±5) J,mol,1,K,1, respectively. Isomerization of the (C-bonded) Ca2+,,,CO carbonyl to yield the (O-bonded) Ca2+,,,OC isocarbonyl involves an enthalpy change =+11.4 (±1.0) kJ,mol,1. These results are compared with previously reported data for the CO/Sr,Y system; and also, a brief analysis of enthalpy,entropy correlation for CO adsorption on zeolites and metal oxides is given. [source] High-Resolution Records of the Holocene Paleoenvironmental Variation Reflected by Carbonate and Its Isotopic Compositions in Bosten Lake and Response to Glacial ActivitiesACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 6 2009ZHANG Chengjun Abstract: The Early Holocene paleoclimate in Bosten Lake on the northern margin of the Tarim Basin, southern Xinjiang, is reconstructed through an analysis of a 953 cm long core (BSTC2000) taken from Bosten Lake. Multiple proxies of this core, including the mineral components of carbonate, carbonate content, stable isotopic compositions of carbonate, Ca/Sr, TOC and C/N and C/S of organic matter, are used to reconstruct the climatic change since 8500 a B.P. The chronology model is made by nine AMS 14C ages of leaves, seeds and organic matter contained in two parallel cores. The climate was cold and wet during 8500 to 8100 a B.P. Temperature increased from 8100 to 6400 a B.P., the climate was warm and humid, and the lake expanded. The lake level was highest during this stage. Then from 6400 to 5100 a B.P., the climate became cold and the lake level decreased slightly. During the late mid-Holocene, the climate was hot and dry from 5100 to 3100 a B.P., but there was a short cold period during 4400 to 3800 a B.P. At this temporal interval, a mass of ice and snow melting water supplied the lake at the early time and made the lake level rise. The second highest lake level stage occurred during 5200 to 3800 a B.P. The climate was cool and wet during 3100 to 2200 a B.P., when the lake expanded with decreasing evaporation. The lake had the last short-term high level during 3100 to 2800 a B.P. After this short high lake level period, the lake shrank because of the long-term lower temperature and reduced water supply. From 2200 to 1200 a B.P., the climate was hot and dry, and the lake shrank greatly. Although the temperature decreased somewhat from 1200 a B.P. to the present, the climate was warm and dry. The lake level began to rise a little again, but it did not reach the river bed altitude of the Konqi River, an outflow river of the Bosten Lake. [source] Factors controlling the activity of the SERCA2a pump in the normal and failing heartBIOFACTORS, Issue 6 2009Ilse Vandecaetsbeek Abstract Heart failure is the leading cause of death in western countries and is often associated with impaired Ca2+ handling in the cardiomyocyte. In fact, cardiomyocyte relaxation and contraction are tightly controlled by the activity of the cardiac sarco(endo)plasmic reticulum (ER/SR) Ca2+ pump SERCA2a, pumping Ca2+ from the cytosol into the lumen of the ER/SR. This review addresses three important facets that control the SERCA2 activity in the heart. First, we focus on the alternative splicing of the SERCA2 messenger, which is strictly regulated in the developing heart. This splicing controls the formation of three SERCA2 splice variants with different enzymatic properties. Second, we will discuss the role and regulation of SERCA2a activity in the normal and failing heart. The two well-studied Ca2+ affinity modulators phospholamban and sarcolipin control the activity of SERCA2a within a narrow window. An aberrantly high or low Ca2+ affinity is often observed in and may even trigger cardiac failure. Correcting SERCA2a activity might therefore constitute a therapeutic approach to improve the contractility of the failing heart. Finally, we address the controversies and unanswered questions of other putative regulators of the cardiac Ca2+ pump, such as sarcalumenin, HRC, S100A1, Bcl-2, HAX-1, calreticulin, calnexin, ERp57, IRS-1, and ,2. © 2009 International Union of Biochemistry and Molecular Biology, Inc. [source] Glutathione transport in the endo/sarcoplasmic reticulum,BIOFACTORS, Issue 1-4 2003Miklós Csala Glutathione transport through the endo/sarcoplasmic reticulum (ER/SR) membrane might play a role in the maintenance of the thiol redox potential difference between the lumen and the cytosol. The transport of glutathione (both GSH and glutathione disulfide, GSSG) is entirely different in the ER and SR membranes. The transport measurements based on either rapid filtration or light scattering techniques revealed that the SR membrane transports glutathione much faster than the hepatic ER membrane or microsomal membranes prepared from heart or brain. The fastest transport has been measured in the membrane of muscle terminal cisternae, which is enriched in ryanodine receptor type 1 (RyR1). All the studied membranes have been found to be equally impermeable to various hydrophilic substances of similar size to glutathione, thus the glutathione transport in muscle microsomes and terminal cysternae as well as the correlation between the rate of glutathione transport and the abundance of RyR1 are specific. In both muscle microsomes and terminal cysternae, glutathione influx can be either inhibited or activated by antagonists and agonists of the ryanodine receptor, respectively, while these agents do not influence the transport of other small permeant molecules. These findings strongly suggest that the ryanodine receptor channel activity is directly associated with glutathione transport activity in the skeletal muscle sarcoplasmic reticulum membrane. [source] Al14Ba8La26.3Ru18Sr53.7O167: a variant of cubic perovskite with isolated RuO6 unitsACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2010F. J. Zúńiga The crystal structure of the title aluminium barium lanthanum ruthenium strontium oxide has been solved and refined using neutron powder diffraction to establish the parameters of the oxygen sublattice and then single-crystal X-ray diffraction data for the final refinement. The structure is a cubic modification of the perovskite ABO3 structure type. The refined composition is Ba0.167La0.548Sr1.118Ru0.377Al0.290O3.480, and with respect to the basic perovskite structure type it might be written as (Ba8La13.68Sr34.32)(Al13.92La12.64Ru18.08Sr19.36)O192,x, with x = 24.96. The metal atoms lie on special positions. The A -type sites are occupied by Ba, La and Sr. The Ba atoms are located in a regular cuboctahedral environment, whereas the La and Sr atoms share the same positions with an irregular coordination of O atoms. The B -type sites are divided between two different Wyckoff positions occupied by Ru/Al and La/Sr. Only Al and Ru occupy sites close to the ideal perovskite positions, while La and Sr move away from these positions toward the (111) planes with high Al content. The structure contains isolated RuO6 octahedra, which form tetrahedral substructural units. [source] An improvement of quantum parametric methods by using SGSA parameterization technique and new elementary parametric functionalsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 3 2010M. Sánchez Abstract A systematic improvement of parametric quantum methods (PQM) is performed by considering: (a) a new application of parameterization procedure to PQMs and (b) novel parametric functionals based on properties of elementary parametric functionals (EPF) [Ruette et al., Int J Quantum Chem 2008, 108, 1831]. Parameterization was carried out by using the simplified generalized simulated annealing (SGSA) method in the CATIVIC program. This code has been parallelized and comparison with MOPAC/2007 (PM6) and MINDO/SR was performed for a set of molecules with CC, CH, and HH bonds. Results showed better accuracy than MINDO/SR and MOPAC-2007 for a selected trial set of molecules. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [source] A Rb/Sr record of catchment weathering response to Holocene climate change in Inner MongoliaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2006Zhangdong Jin Abstract Variation in the rubidium to strontium (Rb/Sr) ratio of the loess,palaeosol sequences has been proposed to reflect the degree of pedogenesis and weathering in the northwestern region of China. To characterize the Rb/Sr ratio of the dissolved loads of a single catchment, we analysed a 12·08 m sediment core from Daihai Lake in Inner Mongolia, north China. Dating control was provided by 210Pb, 137Cs and AMS- 14C. Sequential extraction experiments were conducted to investigate the concentrations of Rb and Sr on various chemical fractions in the lake sediments. Down-core variation in the Rb/Sr ratios provides a record of Holocene weathering history. From 9 to 3·5 ka bp, accelerated chemical weathering was experienced throughout the Daihai catchment under mainly warm and humid conditions, and this reached a maximum at c. 5 ka bp. However, weathering was reduced between c. 8·25 and 7·90 ka bp, which may reflect the global 8·2 ka cooling event. After c. 2·5 ka bp, increased Rb/Sr ratios with higher frequency of fluctuations indicate reduced weathering within the Daihai catchment. The highest Rb/Sr ratios in the Little Ice Age lake sediments indicate the weakest phase of Holocene chemical weathering, resulting from a marked reduction in Sr flux into the basin. The Rb/Sr record also shows an enhancement of chemical weathering under today's climate, but its intensity is less than that of the Medieval Warm Period. Increased Rb/Sr in lake sediment corresponding to reduced catchment weathering is in striking contrast to Rb/Sr decrease in the glacial loess layers in the loess,palaeosol sequence. Copyright © 2005 John Wiley & Sons, Ltd. [source] The major- and trace-element whole-rock fingerprints of Egyptian basalts and the provenance of Egyptian artefactsGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 7 2001John D. Greenough Discrimination diagrams have been developed that source Egyptian basaltic artefacts using whole-rock major element geochemistry. These include K2O versus SiO2, TiO2 and P2O5 against MgO/Fe2O3t (total Fe as Fe2O3), and a discriminant analysis diagram using SiO2, Fe2O3t, CaO, and MnO. A complementary set of diagrams uses easily obtained trace element data (Nb/Y versus Zr/Nb; Zr [ppm] versus Rb/Sr; TiO2 [wt % volatile free] versus V; and Cr [ppm] versus Zr/Y) to determine the bedrock sources. These diagrams have been applied to seven First Dynasty basalt vessels (Abydos), two Fourth Dynasty basalt paving stones (Khufu's funerary temple, Giza), and two Fifth Dynasty paving stones (Sahure's complex, Abu Sir). They show that the bedrock source for all the artefacts was the Haddadin flow in northern Egypt. Multidimensional scaling and cluster analysis applied to the whole-rock data (major elements and trace elements together) and previously published mineral fingerprinting studies confirm these results. Comparing mineral versus whole-rock fingerprinting techniques, a major advantage of the former is the small sample size required (0.001 g compared to , 0.1 g). Analytical costs are similar for both methods assuming that a comparison (bedrock) database can be assembled from the literature. For most archaeological problems, a whole-rock bedrock database is more likely to exist than a mineral database, and whole-rock analyses on artefacts will generally be easier to obtain than mineral analyses. Whole-rock fingerprinting may be more sensitive than mineral-based fingerprinting. Thus, if sample quantity is not an issue, whole-rock analysis may have a slight cost, convenience, and technical advantage over mineral-based methods. Our results also emphasize that the Egyptians cherished their Haddadin basalt flow and used it extensively and exclusively for manufacturing basalt vessels and paving stones for at least 600 years (,3150 B.C. to 2500 B.C., approximate ages of the vessels and Abu Sir paving stones, respectively). © 2001 John Wiley & Sons, Inc. [source] Yellow-brown earth on Quaternary red clay in Langxi County, Anhui Province in subtropical China: Evidence for paleoclimatic change in late Quaternary period,JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2008Xue-Feng Hu Abstract In order to investigate the paleoclimatic changes in S China during the late Quaternary and their influence on pedogenesis and soil classification, a yellow-brown earth (YBE),red clay (RC) profile in Langxi County, Anhui Province was studied. The grain-size distribution and the major- and trace-element compositions of the profile indicate that the YBE of the profile shares the same origin with the YBE in Jiujiang and Xuancheng and the Xiashu loess in Zhenjiang, and the underlying RC also has aeolian characteristics and shares the same origin with the Xiashu loess. Grain-size characteristics, molecular ratios of SiO2/Al2O3, SiO2/(Al2O3+Fe2O3), and BA ([CaO+MgO+K2O+Na2O]/Al2O3) and other weathering indices (CaO/TiO2, MgO/TiO2, K2O/TiO2, Na2O/TiO2, and Rb/Sr) of the profile indicate that the RC is more strongly weathered than the YBE. Magnetic susceptibility (,lf) of the uniform red clay (URC) of the profile is significantly enhanced. However, that of the underlying reticulate red clay (RRC) is significantly decreased because of the paleogroundwater movement and cannot indicate its strong weathering properties. The YBE-RC profile in Langxi County recorded a great climatic change during late Quaternary: At that time, the pedogenic development of the RC was terminated and widespread dust deposition occurred. The parent material of the RC may be aeolian deposits which were accumulated before the last interglacial and were strongly weathered and rubified under the subsequent interglacial climate. It is observed that red soils, derived from the RC, and yellow-brown soils, derived from the YBE, coexist in the study area, which is contradictive to the theory of the zonal distribution of soils. Therefore, it is necessary to take into account the history of Quaternary climatic changes when studying pedogenesis. [source] A simple method to estimate the contribution of biological floc and reactor-solution to mass transfer of oxygen in activated sludge processesBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2005Venkatram Mahendraker Abstract In this study, the mass transfer coefficient of biological floc (KLabf) was estimated from the mass transfer coefficient of the mixed-liquor (KLaf) and the reactor-solution (KLae). The biological floc resistance (BFR) and reactor-solution resistance (SR) were defined as the reciprocal of KLabf and KLae, respectively, by applying the concept of serial-resistance originally presented in two-film theory (Lewis and Whitman (1924) Ind Eng Chem 16:1215,1220). The specific biological floc resistance (SBFR) was defined as biological floc resistance per unit biomass concentration. The data indicated that an activated sludge process yielding low BFR/MLR and BFR/SR tended to produce higher oxygen transfer efficiency. Surprisingly, the reactor-solution posed the same level of resistance as clean water in all experiments, except in a 5-day SRT, non-nitrifying, completely mixed activated sludge (CMAS) process run. Furthermore, SBFR successfully represented biological floc and showed a positive correlation to sludge volume index (SVI). In addition, SBFR/SR and oxygen transfer efficiency (OTEf) followed an exponential relationship for the complete data set. The method of separating the mixed-liquor into biological floc and reactor-solution improved the understanding of oxygen transfer under process conditions, without resorting to intrusive techniques or direct handling of fragile biological floc. © 2005 Wiley Periodicals, Inc. [source] A comparison of concurrent programming and cooperative multithreading under load balancing applicationsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2004Justin T. Maris Abstract Two models of thread execution are the general concurrent programming execution model (CP) and the cooperative multithreading execution model (CM). CP provides nondeterministic thread execution where context switches occur arbitrarily. CM provides threads that execute one at a time until they explicitly choose to yield the processor. This paper focuses on a classic application to reveal the advantages and disadvantages of load balancing during thread execution under CP and CM styles; results from a second classic application were similar. These applications are programmed in two different languages (SR and Dynamic C) on different hardware (standard PCs and embedded system controllers). An SR-like run-time system, DesCaRTeS, was developed to provide interprocess communication for the Dynamic C implementations. This paper compares load balancing and non-load balancing implementations; it also compares CP and CM style implementations. The results show that in cases of very high or very low workloads, load balancing slightly hindered performance; and in cases of moderate workload, both SR and Dynamic C implementations of load balancing generally performed well. Further, for these applications, CM style programs outperform CP style programs in some cases, but the opposite occurs in some other cases. This paper also discusses qualitative tradeoffs between CM style programming and CP style programming for these applications. Copyright © 2004 John Wiley & Sons, Ltd. [source] Calmodulin kinase II initiates arrhythmogenicity during metabolic acidification in murine heartsACTA PHYSIOLOGICA, Issue 1 2009T. H. Pedersen Abstract Aim:, The multifunctional signal molecule calmodulin kinase II (CaMKII) has been associated with cardiac arrhythmogenesis under conditions where its activity is chronically elevated. Recent studies report that its activity is also acutely elevated during acidosis. We test a hypothesis implicating CaMKII in the arrhythmogenesis accompanying metabolic acidification. Methods:, We obtained monophasic action potential recordings from Langendorff-perfused whole heart preparations and single cell action potentials (AP) using whole-cell patch-clamped ventricular myocytes. Spontaneous sarcoplasmic reticular (SR) Ca2+release events during metabolic acidification were investigated using confocal microscope imaging of Fluo-4-loaded ventricular myocytes. Results:, In Langendorff-perfused murine hearts, introduction of lactic acid into the Krebs-Henseleit perfusate resulted in abnormal electrical activity and ventricular tachycardia. The CaMKII inhibitor, KN-93 (2 ,m), reversibly suppressed this spontaneous arrhythmogenesis during intrinsic rhythm and regular 8 Hz pacing. However, it failed to suppress arrhythmia evoked by programmed electrical stimulation. These findings paralleled a CaMKII-independent reduction in the transmural repolarization gradients during acidosis, which previously has been associated with the re-entrant substrate under other conditions. Similar acidification produced spontaneous AP firing and membrane potential oscillations in patch-clamped isolated ventricular myocytes when pipette solutions permitted cytosolic Ca2+ to increase following acidification. However, these were abolished by both KN-93 and use of pipette solutions that held cytosolic Ca2+ constant during acidosis. Acidosis also induced spontaneous Ca2+ waves in isolated intact Fluo-4-loaded myocytes studied using confocal microscopy that were abolished by KN-93. Conclusion:, These findings together implicate CaMKII-dependent SR Ca2+ waves in spontaneous arrhythmic events during metabolic acidification. [source] Corporate social responsibility in Malaysia , experts' views and perspectivesCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2009Jye Y. Lu Abstract The field of corporate social responsibility (CSR) has grown exponentially in the last decade and is gradually becoming a global trend. Companies are now expected to take explicitly into account all aspects of their performance, i.e., not just their financial results, but also their social and environmental performance. Therefore more organizations are now engaged in serious efforts to define and integrate CSR into all aspects of their businesses. The aim of our study is to understand this trend in Malaysia and specifically to investigate (i) The status of CSR in Malaysia; (ii) Different CSR practices in Malaysia; and (iii) Future diffusion of CSR in Malaysia. To answer these questions, we have conducted interviews with Malaysian leading experts in CSR. Our results suggests that the key issues in the journey toward wider diffusion and acceptance of CSR in Malaysia include current confusion over the meaning of CSR, the prevalent use of CSR as a PR tool, mandatory versus voluntary CSR and the role the National Mirror Committee of ISO/TMB/WG SR in this process. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment. [source] A comparative study for profiling ultrathin boron layers in SiCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2003E. Basaran Abstract The carrier concentration-depth profiles of ultrathin boron layers in Si, grown by molecular beam epitaxy, are determined by the electrochemical capacitance-voltage (ECV) and the spreading resistance (SR) profiling techniques. Secondary ion mass spectrometry (SIMS) is employed as a base for the comparison of the results. It has been shown that, under carefully chosen conditions, both ECV and SR techniques are able to resolve ultrathin layers including a delta layer, however ECV match better with the results of SIMS than that of SR. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Indicators of pretreatment suicidal ideation in adults with major depressive disorderACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010D. W. Morris Morris DW, Trivedi MH, Husain MM, Fava M, Budhwar N, Wisniewski SR, Miyahara S, Gollan JK, Davis LL, Daly EJ, Rush AJ. Indicators of pretreatment suicidal ideation in adults with major depressive disorder. Objective:, In order to evaluate the presence of treatment emergent suicidal ideation (SI), it becomes necessary to identify those patients with SI at the onset of treatment. The purpose of this report is to identify sociodemographic and clinical features that are associated with SI in major depressive disorder (MDD) patients prior to treatment with a selective serotonin reuptake inhibitor. Method:, This multisite study enrolled 265 out-patients with non-psychotic MDD. Sociodemographic and clinical features of participants with and without SI were compared post hoc. Results:, Social phobia, bulimia nervosa, number of past depressive episodes, and race were independently associated with SI by one or more SI measure. Conclusion:, Concurrent social phobia and bulimia nervosa may be potential risk factors for SI in patients with non-psychotic MDD. Additionally, patients with more than one past depressive episode may also be at increased risk of SI. [source] Fractional Photothermolysis for Photoaging of HandsDERMATOLOGIC SURGERY, Issue 1 2008MING H. JIH MD BACKGROUND Laser treatment for photoaging of the hands should ideally address pigmentary alteration as well as associated skin roughness and wrinkling. Fractional resurfacing has been previously shown to effectively treat facial rhytids and dyschromia. OBJECTIVE We examined the effect of fractional resurfacing for photoaging of the hands. METHODS AND MATERIALS Ten patients (skin phototypes II to IV) with hand photodamage were randomized to receive five treatments with a 1,550-nm diode-pumped erbium fiber laser (Fraxel SR, Reliant Technologies) laser on either the right or left hand. Treatments were performed at settings of 8 to 9 mJ/microscopic treatment zone and density of 2,500 microscopic treatment zones/cm2. Subjective assessments by the patients and investigator were performed for skin roughness, wrinkling, and pigmentation using a 5-point scale. Skin biopsies were taken at baseline and at 1 and 3 months. RESULTS Patient subjective assessment and physician clinical assessment at 1 and 3 months revealed a mean 51% to 75% improvement in skin pigmentation and 25% to 50% improvement in skin roughness and wrinkling. Biopsies of the skin showed increased density of dermal collagen. Patients experienced transient erythema and edema and none had scarring or other adverse effects. LIMITATIONS This was a small study. CONCLUSION Fractional resurfacing appears to be an effective and safe treatment modality for correcting both the pigmentary and the textural aspects of photoaging of the hand. [source] Social anxiety disorder: what are we losing with the current diagnostic criteria?ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010A. S. Filho Filho AS, Hetem LAB, Ferrari MCF, Trzesniak C, Martín-Santos R, Borduqui T, de Lima Osório F, Loureiro SR, Busatto Filho G, Zuardi AW, Crippa JAS. Social anxiety disorder: what are we losing with the current diagnostic criteria? Objective:, To assess the rate of comorbidities and the functional impairment associated with the social anxiety disorder (SAD), with an emphasis on the so-called subthreshold clinical signs and symptoms. Method:, Psychiatric comorbidities and psychosocial functioning were evaluated in 355 volunteers (college students) who had been diagnosed as SAD (n = 141), Subthreshold SAD (n = 92) or Controls (n = 122). Results:, The rate of comorbidities was 71.6% in the SAD group and 50% in subjects with Subthreshold SAD, both significantly greater than Controls (28.7%). Concerning psychosocial functioning, the SAD group had higher impairment than the other two groups in all domains evaluated, and subjects with Subthreshold SAD presented intermediate values. Conclusion:, The rates of psychiatric comorbidities and the impairment of psychosocial functioning increase progressively along the spectrum of social anxiety. The fact that Subthreshold SAD causes considerable disability and suffering in comparison with control subjects justifies a review of the validity of the diagnostic criteria. [source] Effect of a nutritional liquid supplement designed for the patient with diabetes mellitus (Glucerna SR) on the postprandial glucose state, insulin secretion and insulin sensitivity in healthy subjectsDIABETES OBESITY & METABOLISM, Issue 3 2006M. González-Ortiz Aim:, To identify the effect of a nutritional liquid supplement designed for the patient with diabetes mellitus (Glucerna SR) in single administration on the postprandial glucose state, insulin secretion and insulin sensitivity in healthy subjects. Methods:, A randomized, single-blind, cross-over, clinical trial was carried out in 14 young, healthy, non-obese, volunteers. A basal metabolic profile, which included glucose level, insulin, total cholesterol, high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides, creatinine, and uric acid, was measured. Subjects received a single administration of 300 kcal, gauged with water at 350 ml, of each of the following (at least 3 days apart): glucose 75 g, polymeric supplement (Ensure high calcium) 315 ml or Glucerna SR 323 ml. At the beginning of each administration and 30, 60, 90 and 120 min later, glucose and insulin concentrations were measured. Areas under the curve of glucose and insulin were calculated. First-phase and total insulin secretions and insulin sensitivity were also estimated. Results:, Glucose level at 120 min was significantly lower after receiving Ensure high calcium or Glucerna SR. Administration of Glucerna SR resulted in a significant reduction in the areas under the curve of glucose and insulin, as well as in total insulin secretion with a tendency to be lower in their first phase. Insulin sensitivity was increased. Conclusions:, A single administration of Glucerna SR to healthy subjects decreased the postprandial glucose and insulin states, as well as the insulin secretion; insulin sensitivity increased. [source] Are CB1 receptor antagonists nootropic or cognitive impairing agents?DRUG DEVELOPMENT RESEARCH, Issue 8 2009Stephen A. Varvel Abstract For more than a decade, a considerable amount of research has examined the effects of rimonabant (SR 141716) and other CB1 receptor antagonists in both in vivo and in vitro models of learning and memory. In addition to its utility in determining whether the effects of drugs are mediated though a CB1 receptor mechanism of action, these antagonists are useful in providing insight into the physiological function of the endogenous cannabinoid system. Several groups have reported that CB1 receptor antagonists enhance memory duration in a variety of spatial and operant paradigms, but not in all paradigms. Conversely, disruption of CB1 receptor signaling also impairs extinction learning in which the animal actively suppresses a learned response when reinforcement has been withheld. These extinction deficits occur in aversively motivated tasks, such as in fear conditioning or escape behavior in the Morris water maze task, but not in appetitively motivated tasks. Similarly, in electrophysiological models, CB1 receptor antagonists elicit a variety of effects, including enhancement of long-term potentiation (LTP), while disrupting long-term depression (LTD) and interfering with transient forms of plasticity, including depolarization-induced suppression of inhibition (DSI) and depolarization-induced suppression of excitation (DSE). The collective results of the in vivo and in vitro studies employing CB1 receptor antagonists, demonstrate that these receptors play integral roles in different components of cognitive processing. Functionally, pharmacological blockade of CB1 receptors may strengthen memory duration, but interferes with extinction of learned behaviors that are associated with traumatic or aversive memories. Drug Dev Res 70:555,565, 2009. © 2009 Wiley-Liss, Inc. [source] Relationship between Strain Rate Imaging and Coronary Flow Reserve in Assessing Myocardial Viability after Acute Myocardial InfarctionECHOCARDIOGRAPHY, Issue 8 2010Ph.D., Seong-Mi Park M.D. Objectives: To evaluate the relationship between strain rate (SR) imaging and coronary flow reserve (CFR) in assessing viability of akinetic myocardium after acute myocardial infarction (MI). Methods: Forty patients with acute first ST-elevation MI were analyzed. SR imaging and CFR by intracoronary flow measurement were obtained on the same day, 3,5 days after primary percutaneous coronary intervention. Viability of the akinetic myocardium was determined on 6-week echocardiography. Results: Systolic SR (SRs, ,0.42 ± 0.10 vs. ,0.35 ± 0.11 per second, P = 0.03), early diastolic SR (SRe, 0.68 ± 0.31 vs. 0.41 ± 0.22 per second, P = 0.003), and systolic strain (Ss, ,5.9 ± 3.4 vs. ,2.5 ± 4.0%, P = 0.04) were greater in akinetic, but viable myocardium of 21 patients than in akinetic and nonviable myocardium of 19 patients. CFR was also higher in patients with akinetic, but viable myocardium (2.0 ± 0.5 vs. 1.5 ± 0.5, P < 0.001). SRs, SRe, and Ss were significantly related to CFR (r =,0.50, r = 0.58, r =,0.56, respectively, all P , 0.001) and SRe was most related to CFR (P < 0.001). The sensitivity and specificity to predict myocardial viability were 85.7% and 68.4% for CFR (cutoff = 1.75), and 90.5% and 57.9% for SRe (cutoff = 0.37 per second), respectively. Conclusions: The degree of myocardial deformation determined by SR imaging was related to the degree of microvascular integrity determined by CFR, and can be used as a noninvasive method to predict myocardial viability after acute MI. (Echocardiography 2010;27:977-984) [source] Detection of Subclinical Cardiac Involvement in Systemic Sclerosis by Echocardiographic Strain ImagingECHOCARDIOGRAPHY, Issue 2 2008Alper Kepez M.D. Background: Cardiac involvement is one of the major problems in systemic sclerosis (SSc). Subclinical cardiac involvement has a higher frequency than thought previously. In this study we investigated whether subclinical cardiac involvement can be detected by using echocardiographic strain imaging in SSc patients without pulmonary hypertension. Methods: Echocardiographic examinations were performed to 27 SSc patients and 26 healthy controls. Left ventricular strain parameters were obtained from apical views and average strain value was calculated from these measurements. Results: There were no significant differences between patients and controls regarding two-dimensional (2D), conventional Doppler and tissue Doppler velocity measurements. Strain was reduced in 6 of 12 segments of the left ventricle (LV) and in 1 of 2 segments of the right ventricle (RV). Strain rate (SR) was reduced in 2 of 12 segments of the LV and 1 of 2 segments of the RV in SSc patients as compared to controls (P < 0.05 for all). These involvements did not match any particular coronary artery distribution. More important differences were detected by average strain and SR values of the LV between patients and controls (19.78 ± 3.00% vs 23.41 ± 2.73%, P < 0.001; 2.01 ± 0.41 vs 2.23 ± 0.27/sec, P = 0.026, respectively). Furthermore, carbon monoxide diffusion capacity (DLCO) in scleroderma patients significantly correlated with LV average strain (r = 0.59; P = 0.001). Conclusion: Evaluation of ventricular function by using echocardiographic strain imaging appears to be useful to detect subclinical cardiac involvement in SSc patients with normal standard echocardiographic and tissue Doppler velocity findings. [source] Predictors for Maintenance of Sinus Rhythm after Cardioversion in Patients with Nonvalvular Atrial FibrillationECHOCARDIOGRAPHY, Issue 5 2002Ökçün M.D. Recurrence of atrial fibrillation (AF) after cardioversion (CV) to sinus rhythm (SR) is determined by various clinical and echocardiographic parameters. Transesophageal echocardiographic (TEE) parameters have been the focus of clinicians' interests for restoring and maintaining SR. This study determined the clinical, transthoracic, and TEE parameters that predict maintenance of SR in patients with nonvalvular AF after CV. We enrolled 173 patients with nonvalvular AF in the study. TEE could not be performed in 26 patients prior to CV. Twenty-five patients had spontaneously CV prior to TEE. Six patients were excluded because of left atrial (LA) thrombus assessed by TEE. CV was unsuccessful in 6 patients. The remaining 110 consecutive patients (56 men, 54 women, mean age 69 ± 9 years), who had been successfully cardioverted to SR, were prospectively included in the study. Fifty-seven (52%) patients were still in SR 6 months after CV. Age, gender, the configuration of the fibrillation wave on the electrocardiogram, pulmonary venous diastolic flow, and the presence of diabetes, hypertension, coronary artery disease, mitral annulus calcification, and mitral valve prolapse (MVP) did not predict recurrence. Duration of AF, presence of chronic obstructive pulmonary disease (COPD), LA diameter, left ventricular ejection fraction (EF), left atrial appendage peak flow (LAAPF), LAA ejection fraction (LAAEF), pulmonary venous systolic flow (PVSF), and the presence of LA spontaneous echo contrast (LASEC) predicted recurrence of AF 6 months after CV. In multivariate analysis, LAAEF < 30% was found to be the only independent variable (P < 0.0012) predicting recurrence at 6 months after CV in patients with nonvalvular AF. LAAEF more than 30% had a sensitivity of 75% and a specificity of 88% in predicting maintenance of SR 6 months after CV in patients with nonvalvular AF. In conclusion, TEE variables often used to determine thromboembolic risk also might be used to predict the outcome of CV. [source] Stability Enhancement of All-Solid-State H+ ISEs with Cross-Linked Silicon-Urethane MatricesELECTROANALYSIS, Issue 8 2005Nak-Hyun Kwon Abstract An all-solid-state hydrogen-ion-selective electrode (ASHISE) was fabricated using the polymer hybrid membrane. Polymer membranes composed of Tecoflex polyurethane (TPU), polyvinyl chloride (PVC), silicon rubber (SR), and additives (KTpClPB, DOA, and TDDA) were cast on a carbon rod. The TPU/SR hybrid membrane exhibited a longer lifetime and a higher sensitivity in the sensing of the H+ ion compared to conventional TPU/PVC and PVC/SR hybrid membranes. Moreover, the addition of SiCl4 to TPU-based matrices enhanced the potentiometric response and ISE stability, due to the chemical bonding between Si and CO in urethane, in which the cross-linking configuration was confirmed by DSC, FT-IR, and XPS experiments. TPU/SR membranes containing SiCl4 were rendered more stable and showed a pH response over a wide range (i.e., pH,2,11.5) with the slope of 60±2,mV/pH for more than four months. The ASHISE exhibited a small interfering potential variation in the wide range of the salt concentration (from 1.0×10,6,M up to 0.1,M). The ASHISE showed a result comparable to a commercial clinical blood analyzer. [source] Monitoring pyrethroid resistance in field collected Blattella germanica Linn. (Dictyoptera: Blattellidae) in IndonesiaENTOMOLOGICAL RESEARCH, Issue 2 2009Intan AHMAD Abstract The German cockroach, Blattella germanica, is a major and the most common pest in public areas in Indonesia. Although intensive control measures have been carried out to control the populations of this pest, results have been far from successful, which is believed to be because of its resistance to insecticides. A standard World Health Organization (WHO) glass jar test was carried out to determine the resistance level of this insect to pyrethroid insecticides, the most commonly used insecticides for cockroach control in Indonesia. A susceptible S1 strain collected from Tembagapura Papua was compared with four strains collected from Bandung, West Java: strain S2, from a local restaurant; strain S3, from the Bandung train station; and strains S4 and S5, from two different hotels. All strains showed low resistance to the pyrethroid, except the S5 strain, which had a Resistance Ratio (RR)50 of 95 for permethrin. The addition of piperonyl butoxide (PBO) suggests that the detoxifying enzyme mixed function oxidases (MFO) played an important role in the development of resistance to permethrin in the S5 strain, suggested by the high Synergist Ratio (SR) of 70.4. However, the low level of resistance to cypermethrin was not affected by PBO, suggesting that other mechanisms of pyrethroid resistance are involved. Our study is the first report of German cockroach resistance to permethrin in Indonesia, and the findings can be used in formulating potential strategies for cockroach resistance management. [source] On the relationship between methane production and oxidation by anaerobic methanotrophic communities from cold seeps of the Gulf of MexicoENVIRONMENTAL MICROBIOLOGY, Issue 5 2008Beth! Orcutt Summary The anaerobic oxidation of methane (AOM) in the marine subsurface is a significant sink for methane in the environment, yet our understanding of its regulation and dynamics is still incomplete. Relatively few groups of microorganisms consume methane in subsurface environments , namely the anaerobic methanotrophic archaea (ANME clades 1, 2 and 3), which are phylogenetically related to methanogenic archaea. Anaerobic oxidation of methane presumably proceeds via a ,reversed' methanogenic pathway. The ANME are generally associated with sulfate-reducing bacteria (SRB) and sulfate is the only documented final electron acceptor for AOM in marine sediments. Our comparative study explored the coupling of AOM with sulfate reduction (SR) and methane generation (MOG) in microbial communities from Gulf of Mexico cold seep sediments that were naturally enriched with methane and other hydrocarbons. These sediments harbour a variety of ANME clades and SRB. Following enrichment under an atmosphere of methane, AOM fuelled 50,100% of SR, even in sediment slurries containing petroleum-associated hydrocarbons and organic matter. In the presence of methane and sulfate, the investigated microbial communities produce methane at a small fraction (,10%) of the AOM rate. Anaerobic oxidation of methane, MOG and SR rates decreased significantly with decreasing concentration of methane, and in the presence of the SR inhibitor molybdate, but reacted differently to the MOG inhibitor 2-bromoethanesulfonate (BES). The addition of acetate, a possible breakdown product of petroleum in situ and a potential intermediate in AOM/SR syntrophy, did not suppress AOM activity; rather acetate stimulated microbial activity in oily sediment slurries. [source] Extended cognitive behavior therapy for cigarette smoking cessationADDICTION, Issue 8 2008Joel D. Killen ABSTRACT Primary aim Examine the effectiveness of extended cognitive behavior therapy (CBT) in promoting longer-term smoking abstinence. Design Open-label treatment phase followed by extended treatment phase. Randomization conducted prior to entry into open-label treatment phase; analysis based on intention-to-treat to avoid threat of selection bias. Setting Community smoking cessation clinic. Participants A total of 304 adult smokers (,18 years of age; ,10 cigarettes/day). Intervention Open-label (8 weeks): all participants received bupropion SR, nicotine patch, CBT. Extended treatment (12 weeks): participants received either CBT + voicemail monitoring and telephone counseling or telephone-based general support. Measurements Seven-day point prevalence abstinence, expired-air carbon monoxide. Results At week 20 follow-up, CBT produced a higher 7-day point prevalence abstinence rate: 45% versus 29%, P = 0.006; at 52 weeks the difference in abstinence rates (31% versus 27%) was not significant. History of depression was a moderator of treatment. Those with a positive history had a better treatment response at 20 weeks when assigned to the less intensive telephone support therapy (P < 0.05). Conclusion The superiority of CBT to 20 weeks suggests that continued emphasis on the development of cognitive and behavioral strategies for maintaining non-smoking during an extended treatment phase may help smokers to maintain abstinence in the longer term. At present, the minimum duration of therapy is unknown. [source] PRECLINICAL STUDY: FULL ARTICLE: Altered architecture and functional consequences of the mesolimbic dopamine system in cannabis dependenceADDICTION BIOLOGY, Issue 3 2010Saturnino Spiga ABSTRACT Cannabinoid withdrawal produces a hypofunction of mesencephalic dopamine neurons that impinge upon medium spiny neurons (MSN) of the forebrain. After chronic treatment with two structurally different cannabinoid agonists, ,9 -tetrahydrocannabinol and CP55 940 (CP) rats were withdrawn spontaneously and pharmacologically with the CB1 antagonist SR141716A (SR). In these two conditions, evaluation of tyrosine hydroxylase (TH)-positive neurons revealed significant morphometrical reductions in the ventrotegmental area but not substantia nigra pars compacta of withdrawn rats. Similarly, confocal analysis of Golgi,Cox-stained sections of the nucleus accumbens revealed a decrease in the shell, but not the core, of the spines' density of withdrawn rats. Administration of the CB1 antagonist SR to control rats, provoked structural abnormalities reminiscent of those observed in withdrawal conditions and support the regulatory role of cannabinoids in neurogenesis, axonal growth and synaptogenesis by acting as eu-proliferative signals through the CB1 receptors. Further, these measures were incorporated into a realistic computational model that predicts a strong reduction in the excitability of morphologically altered MSN, yielding a significant reduction in action potential output. These pieces of evidence support the tenet that withdrawal from addictive compounds alters functioning of the mesolimbic system and provide direct morphological evidence for functional abnormalities associated with cannabinoid dependence at the level of dopaminergic neurons and their postsynaptic counterpart and are coherent with recent hypothesis underscoring a hypodopaminergic state as a distinctive feature of the ,addicted brain'. [source] Coordination Chemistry of 3-Mercapto-2-(mercaptomethyl)propanoic Acid (Dihydroasparagusic Acid) with Iron and NickelEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2006Phillip I. Volkers Abstract The first transition-metal complexes bearing the natural product dihydroasparagusic acid, (HSCH2)2CHCO2H, as a ligand are reported. Various coordination modes and nuclearities are demonstrated for the chelating ligand by a series of iron and nickel complexes. Fe2[(SCH2)2CHCO2H](CO)6 retains carbonyl substitution reactivity typical of Fe2(SR)2(CO)6 complexes, yet carboxy coordination to FeI was unobserved. Coupling of the carboxylic acid with amines yields the corresponding amides Fe2[(SCH2)2CHC(O)NHR](CO)6 (R = Et, gly,O,tBu). Fe2[(SCH2)2CHCO2H](CO)4(PMe3)2 catalyzes H2 production, but no better than unfunctionalized alkyl dithiolate analogs. Reactions of the ligand with NiCl2(dppe) afforded mono-, di-, and trinuclear complexes. Noteworthy is Ni3[(SCH2)2CHCO2]2(dppe)2, which features an octahedrally coordinated NiII center linked to a pair of square-planar NiII centers. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||