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Lifestyle Modification Programs in Polycystic Ovary Syndrome: Systematic Review and Meta-Analysis

JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM 2013年第12期98卷 4655-4663页

作者： Domecq, Juan Pablo Prutsky, Gabriela Mullan, Rebecca J. Hazem, Ahmad Sundaresh, Vishnu Elamin, Mohammed B. Phung, Olivia J. Wang, Amy Hoeger, Kathleen Pasquali, Renato Erwin, Patricia Bodde, Amy Montori, Victor M. Murad, M. Hassan Mayo Clin Knowledge & Evaluat Res Unit Rochester MN 55905 USA Mayo Clin Div Prevent Occupat & Aerosp Med Rochester MN 55905 USA Mayo Clin Div Endocrinol Rochester MN 55905 USA Mayo Clin Div Gen Internal Med Rochester MN 55905 USA Unidad Conocimiento & Evidencia Lima 32 Peru Univ N Dakota Dept Internal Med Fargo ND 58102 USA St Orsola Malpighi Hosp Univ Alma Mater Studiorum Bologna Dept Clin Med Div Endocrinol I-40126 Bologna Italy Univ Minnesota Sch Med Minneapolis MN 55455 USA Louisiana State Univ Hlth Sci Ctr Div Endocrinol & Metab Shreveport LA 70112 USA Univ Rochester Med Ctr Div Reprod Endocrinol Dept Obstet & Gynecol Rochester NY 14627 USA Western Univ Hlth Sci Pomona CA 91766 USA Texas Tech Univ Hlth Sci Ctr Amarillo Dept Med Amarillo TX 79106 USA Wayne State Univ Childrens Hosp Michigan Dept Pediat Sch MedDetroit Med Ctr Detroit MI 48201 USA Henry Ford Hosp Dept Internal Med Detroit MI 48202 USA

Context: Polycystic ovary syndrome (PCOS) is a prevalent disorder that affects women of childbearing age and may be related to obesity and insulin resistance. Objective: The purpose of this systematic review was to appraise the evidence of the impact of lifestyle modification (LSM) interventions on outcomes of women with PCOS. Data Sources: Sources included Ovid Medline, OVID Embase, OVID Cochrane Library, Web of Science, Scopus, PsycINFO, and CINAHL (up to January 2011). Study Selection: We included randomized controlled trials that enrolled woman of any age with PCOS who received LSM and compared them against women who received no intervention, minimal intervention, or metformin. Data Extraction: Two authors performed the data extraction independently. Data Synthesis: We included 9 trials enrolling 583 women with a high loss to follow-up rate, lack of blinding, and short follow-up. Compared with minimal intervention, LSM significantly reduced fasting blood glucose (weighted mean difference, -2.3 mg/dL;95% confidence interval, -4.5 to -0.1, I-2 = 72%, P = .04) and fasting blood insulin (weighted mean difference, -2.1 mu U/mL, 95% confidence interval, -3.3 to -1.0, I-2 = 0%, P < .001). Changes in body mass index were associated with changes in fasting blood glucose (P < .001). Metformin was not significantly better than LSM in improving blood glucose or insulin levels. We found no significant effect of LSM on pregnancy rate, and the effect on hirsutism was unclear. Conclusions: The available evidence suggests that LSM reduces fasting blood glucose and insulin levels in women with PCOS. Metformin has similar effects. Translation of these short-term effects to patient-important outcomes, beyond diabetes prevention, remains uncertain.

关键词： diabetes prevention Meta-Analysis Review, Systematic Metformin Polycystic Ovary Syndrome Body Mass Index linux security module extracting data fasting blood glucose test lifestyle modification Blood Glucose

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Cr poisoning suppression in solid oxide fuel cells using LaNi(Fe)O₃ electrodes

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ELECTROCHEMICAL AND SOLID STATE LETTERS 2006年第1期9卷 A9-A12页

作者： Komatsu, T Arai, H Chiba, R Nozawa, K Arakawa, M Sato, K NTT Corp Energy & Environm Syst Lab Atsugi Kanagawa 2430198 Japan Nagaoka Univ Technol Dept Environm Engn Nagaoka Niigata 9402188 Japan

We have investigated the effect of Cr poisoning on various cells which consist of either LaNi0.6Fe0.4O3 (LNF) or La0.8Sr0.2MnO3 (LSM) as a cathode and either yttria- stabilized zirconia (YSZ) or alumina- doped scandia stabilized zirconia (SASZ) as the electrolyte. It was found that the cathodic overvoltage was almost the same for cells with LNF cathodes, either in the presence or absence of Cr- containing alloy (Inconel 600). LSM cathodes in the presence of Inconel 600 exhibited a very steep increase in voltage curves after applying the current. These results indicate that the LNF cathode is electrochemically stable for Cr poisoning compared with the LSM cathode. (c) 2005 The Electrochemical Society.

关键词： LNF fuel batteries Yttria stabilized zirconia linux security module chromium Solid oxide fuel cells

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The role of 8 mol % yttria stabilized zirconia in the improvement of electrochemical performance of lanthanum manganite composite electrodes

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JOURNAL OF THE ELECTROCHEMICAL SOCIETY 1998年第6期145卷 1932-1939页

作者： Wang, SZ Jiang, Y Zhang, YH Yan, JW Li, WZ Chinese Acad Sci Dalian Inst Chem Phys Dalian 116023 Peoples R China

In this study, 8 mol % yttria stabilized zirconia (YSZ) + La0.8Sr0.2MnO3 (LSM) composite electrodes with addition of various amounts of YSZ were prepared on YSZ plates by a screen-printing method. The electrodes were then examined by scanning electron microscopy (SEM) and studied by ac impedance, cyclic voltammetry, and potential step as well as a polarization technique. For the oxygen reduction reaction on the pure LSM electrode, the dissociative adsorption of oxygen on the LSM surface and the transfer of oxygen ions from the triple-phase boundary (TPB) to the YSZ electrolyte lattice were found to be two comparable rate-determining steps. The electrochemical resistance of the former step was proportional to the -0.5 power of p(O2), with a high activation energy of similar to 2.0 eV. The electrochemical resistance of the latter step was found to be independent of p(O2), with a low activation energy of similar to 1.0 eV. With addition of YSZ to the LSM electrode, the electrochemical activity was improved substantially with much lower electrochemical resistances for both steps. Furthermore, the dissociative adsorption of oxygen became less rate determining on the electrode with more YSZ addition. It was found that the transfer of oxygen ion was the only rate-determining step on the 40% YSZ + LSM electrode. The improvement in the electrochemical performance with addition of YSZ was found mainly due to the spatial enlargement of the TPB area, which increased the electrochemically active sites for the oxygen adsorption and charge-transfer reaction. The intimate sintering of YSZ particles to the YSZ substrate and the subsequent formation of the spatial TPB area were directly found by SEM examination and further confirmed by the increasing cathodic currents from the TPB area, which were separated from the total currents using a potential-step technique.

关键词： Scanning Electron Microscope composite electrode oxygen ions Steps oxygen Electrodes polarization technique linux security module Yttria stabilized zirconia potential step Activation energy

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A General 3D Lattice Spring Model for Modeling Elastic Waves

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BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA 2017年第5期107卷 2194-2212页

作者： Xia, Muming Zhou, Hui Li, Qingqing Chen, Hanming Wang, Yufeng Wang, Shucheng China Univ Petr China Natl Petr Corp Key Lab Geophys Explorat State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China

Forward modeling is the foundation of seismic inversion, migration, and geological interpretation. A general 3D lattice spring model (LSM) based on Hooke's and Newton's laws is devised to mimic elastic wave propagation in the 3D space. A generic equation controlling the weights for calculating the spring force is deduced, and different discrete models can be built by simply choosing different solutions of the equation. Three distinct LSMs with different patterns of springs between the nodes are discussed, and their accuracy is compared against the reference solution given by the staggered finite-difference method. One homogeneous and two heterogeneous 3D models are tested using LSM and finite-difference method. The results obtained by both the simulation methods are hard to distinguish, and LSM is a little more dispersive than finite-difference method, but with a better stability condition. Though different kind of LSM schemes can obtain almost the same wavefields as finite-difference method, they represent the local elastic properties of the material with slightly different accuracy. As we can assume the springs across the cracks or pores are disconnected in LSM, such a discrete scheme can offer a new way to model elastic wave propagation in complex media with discontinuities.

关键词： analog approach Material properties Elastic waves Steady state local elastic properties Finite difference methods linux security module Three Dimensions

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Evaluating model performance and parameter behavior for varying levels of land surface model complexity

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WATER RESOURCES RESEARCH 2006年第8期42卷 8430-1-8430-17-0页

作者： Hogue, Terri S. Bastidas, Luis A. Gupta, Hoshin V. Sorooshian, Soroosh Univ Calif Los Angeles Dept Civil & Environm Engn Los Angeles CA 90095 USA Utah State Univ Dept Civil & Environm Engn Logan UT 84322 USA Univ Arizona Dept Hydrol & Water Resources Tucson AZ 85721 USA Univ Arizona NSF Sci & Technol Ctr Sustainabil Semi Arid Hydro Tucson AZ USA Univ Calif Irvine Dept Civil & Environm Engn Irvine CA 92697 USA

[ 1] This paper investigates model performance and parameter behavior for a range of land surface model ( LSM) complexity across a variety of vegetated surfaces. Although LSMs are used routinely in regional and global climate ( and weather) prediction, there has been limited rigorous testing of these models across a range of biomes. A systems-based approach is used to compare five commonly used LSMs ( BUCKET, CHASM, BATS1e, BATS2, and Noah) across five different vegetated sites ( pasture, short grass, cropland, tropical rain forest, and semiarid desert). Results indicate that there is no "perfect'' model and that additional complexity ( defined as additional physical representation in a model) does not necessarily equate to improved performance. In general, the medium complexity BATS1e model has the most consistent performance, with overall lower errors across the sites. Results also indicate that prescribed parameter meanings are not consistent across the various LSM formulations. A comparison of BATS1e and BATS2 parameters reveals significant differences in behavior across the study sites. These findings have key implications for general application of a single model across a range of global biomes and for model intercomparison studies where parameters are preassigned to participating models.

关键词： RAINFALL-RUNOFF MODELS MULTICRITERIA METHODS HYDROLOGIC-MODELS UNCERTAINTY ESTIMATION AUTOMATIC CALIBRATION SENSITIVITY-ANALYSIS GLOBAL OPTIMIZATION SCHEMES PILPS CATCHMENT SIMULATIONS Biome simulating Complexity Catchment area weather forecasting Global optimization linux security module Sensitivity analysis automatic calibration Land surface Hydrologic models

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Analytical and numerical solutions of fixed and moving boundary problems for liquid surfactant membrane processes

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CHEMICAL ENGINEERING SCIENCE 1996年第11期51卷 3059-3064页

作者： Kim, DH Wainwright, MS Chang, KS Ma, GY POHANG UNIV SCI & TECHNOL CTR AUTOMAT RESPOHANGSOUTH KOREA POHANG UNIV SCI & TECHNOL DEPT CHEM ENGNPOHANGSOUTH KOREA

A mathematical model describing a batch liquid-surfactant-membrane (LSM) process is developed. In addition to unsteady-state diffusion, reaction, and external mass transfer, consumption of the reagent by the reaction is also considered. Thus, depending on the Thiele modulus and the initial amount of the reagent, the model either remains to be a fixed boundary problem throughout the whole process or changes to a moving boundary problem after some initial period of fixed boundary. For the fixed boundary problem a general analytic solution is obtained in an eigenfunction expansion by a self-adjoint formalism in linear operator theory. In contrast to the known perturbation solution, the solution is exact and straightforward to use. For typical operations the series solution converges rapidly within a few terms, providing a useful tool in design and analysis of the LSM process. Also the solution readily enables determination of the time of transition from fixed to moving boundary. For the moving boundary model, a simple numerical method based on a fixed-grid finite difference method is constructed for solution. In this method the position of the moving boundary is approximated to a grid point at which depletion of the reagent occurred most recently. The calculated position of the moving boundary has been found to be accurate to the size of the grid. The method has also been found to be stable and reliable for all practical ranges of its application.

关键词： Model moving boundary THIELE MODULUS grid point fixed boundary Reagents linux security module

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Improvement of intergranular corrosion resistance of type 316 stainless steel by laser surface melting

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SURFACE ENGINEERING 2001年第6期17卷 483-489页

作者： Kumar, S Banerjee, MK Indira Gandhi Ctr Atom Res Kalpakkam 603102 Tamil Nadu India Reg Inst Technol Dept Chem Jamshedpur 831014 Bihar India

Laser surface melting (LSM) on sensitised austenitic stainless steel with various degrees of cold work (5, 10, 15, 20, and 25%) was carried out by using a continuous wave CO2 laser with a maximum power 450 W. The stainless steel was sensitised at 898 K for 10, 20, and 50 h durations. The ASTM A262 Practice A test was used to examine the microstructures of the specimens before and after LSM, while the single loop electrochemical potentiokinetic reactivation (SL-EPR) technique was used to quantify the degree of sensitisation (DOS). A trend is noted between the level of cold work in the stainless steel and the degree of desensitisation by LSM and it is inferred that laser surface melting can be effectively used as a method to improve the intergranular corrosion resistance of austenitic stainless steel. (C) 2001 IoM Communications Ltd.

关键词： Laser surface melting austenitic stainless steels Laser Surface remelting SGCG gene linux security module Intergranular corrosion Desensitization cold working corrosion resistance

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Interface stability among solid oxide fuel cell materials with perovskite structures

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JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2006年第3期153卷 A621-A625页

作者： Sakai, N Horita, T Yamaji, K Brito, ME Yokokawa, H Kawakami, A Matsuoka, S Watanabe, N Ueno, A Natl Inst Adv Ind Sci & Technol Tsukuba Ibaraki 3058565 Japan TOTO Ltd Chigasaki Kanagawa 2538577 Japan

The chemical stability of the interface of lanthanum strontium iron cobalt oxides (LSCF) and lanthanum strontium magnesium gallium oxide (LSGM) was investigated. LSCF and LSGM do not coexist stably, and it makes solid solutions at higher temperatures by the fast interdiffusion of metal components. The bulk and grain boundary diffusivities were determined as a function of temperature for LSGM, LSCF, and lanthanum strontium manganite current collectors. The activation energies of bulk diffusivity of Co or Fe in LSGM or LSM, and Mn in LSCF are around 500 kJ mol(-1). The effect of grain boundary as a fast diffusion path was clearly visualized for manganese diffusion in LSCF. (c) 2006 The Electrochemical Society.

关键词： interface stability lanthanum chemical stability function of temperature linux security module solid solution perovskite manganese Iron Solid oxide fuel cells metal construction

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Impregnation of LSM Based Cathodes for Solid Oxide Fuel Cells

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ELECTROCHEMICAL AND SOLID STATE LETTERS 2011年第7期14卷 B77-B79页

作者： Hojberg, Jonathan Sogaard, Martin Tech Univ Denmark Riso Natl Lab Sustainable Energy Fuel Cells & Solid State Chem Div DK-4000 Roskilde Denmark

Composites cathodes consisting of strontium doped lanthanum manganite (LSM) and yttria stabilized zirconia have been impregnated with the nitrates corresponding to the nominal compositions: La(0.75)Sr(0.25)Mn(1.05)O(3 +/-delta) (LSM25), Ce(0.8)Sm(0.2)O(2) (SDC) and a combination of both (dual). The latter performed best with a polarization resistance (R(P)) of 0.39 Omega cm(2) at 600 degrees C and 0.039 Omega cm(2) at 750 degrees C compared to 2.17 and 0.19 Omega cm(2) respectively for electrodes without impregnation. Furthermore the dual impregnation decreased the activation energy of R(P) to 1.19 eV compared to 1.35 eV for cells without impregnation. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3583497] All rights reserved.

关键词： Cathodes Composites Polarization resistance Electrodes Yttria stabilized zirconia fuel batteries linux security module Activation energy Solid oxide fuel cells

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Particle formation in the rapidly solidified zone of alloy 600 surface melted by a CO₂ laser beam

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METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE 2001年第5期32卷 1248-1251页

作者： Lim, YS Kim, JS Kwon, HS Korea Atom Energy Res Inst Steam Generator Mat Project Taejon 305600 South Korea Korea Adv Inst Sci & Technol Dept Mat Sci & Engn Taejon 305701 South Korea

In recent years, a laser surface melting (LSM) technique has been applied to metals and alloys to improve their surface properties. The beneficial effects of the LSM process have their origin in the rapidly quenched microstructure that is unattainable from conventionally processed alloys under cast and wrought conditions. Lim et al. demonstrated that the improvement in resistance to intergranular attack and intergranular stress corrosion cracking of the sensitized alloy 600 was accomplished by microstructural changes in the laser-melted zone (LMZ) during the LSM process, i.e., complete melting of pre-existing Cr-rich carbides by the high power density of a laser beam, the resultant disappearance (or healing) of Cr-depleted zones, and Cr enrichment in the cell boundaries according to solute microsegregation during *** addition to the preceding metallurgical changes, fine Ti compounds with an approximate size of less than 150 nm were precipitated along the cell boundaries with the generation of tangled dislocations around them in alloy 600. The finely dispersed hard particles with a high number density and associated dislocations might significantly influence the mechanical properties including creep and pitting corrosion. Therefore, the purpose of this article is to reinvestigate the chemical composition, location, and distribution of the particles formed in alloy 600 by the LSM process.

关键词： Melting PARTICLE DISTRIBUTION laser beams LIQUID INJECTION MOLDING linux security module intergranular stress corrosion cracking Intergranular corrosion METAL ALLOY

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