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Degradation behavior of acceptor (Y)-doped (Ba,Ca)(Ti,Zr)O 3 ceramics sintered in moist reducing atmosphere and subsequently re-oxidized in dry or wet atmospheres was contrasted. The degradation behavior critically depends on the water vapor incorporation, the time to degradation systematically decreased with the incorporation of hydroxyl defects ( O H ) O • . The electrical conductivity was investigated by means of impedance spectroscopy (IS) to determine properties, such as grain and grain boundary conductivity, grain boundary potential barrier height, and space charge layer thickness. Furthermore, transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) were applied to consider microstructure, microchemistry, and oxygen stoichiometry changes. [ABSTRACT FROM AUTHOR]

In this study, a numerical simulation is performed to explore oscillatory natural convection in a square enclosure with a phase change material (PCM) suspension using the implicit finite difference method. The following parameters are considered: aspect ratio of the physical model = 1; ratio of the buoyancies caused by temperature and concentration gradients = 1; Rayleigh number = 103-106; initial mass fraction (or concentration) of PCM particles = 0–0.1; Stefan number = 0.005–0.1; and subcooling factor = 0–1.0. The results show that high Rayleigh numbers can easily cause oscillations in the flow field and temperature distribution. However, even under low Rayleigh number conditions, when the initial mass fraction or subcooling is increased or the Stefan number is decreased, oscillations occur. • Heat transfer in an enclosure with PCM suspension was numerically investigated. • Oscillatory natural convection phenomena are found. • High Rayleigh numbers can easily cause the oscillations in the flow and temperature. • High initial mass fraction or subcooling can cause, even under low Rayleigh numbers. • Low Stefan numbers cause too, under low Rayleigh numbers. [ABSTRACT FROM AUTHOR]

Introduction: Statin may induce epithelial dysfunction of the bladder urothelium. Epithelial dysfunction was proposed as one of the major potential etiologies for bladder pain syndrome/interstitial cystitis (BPS/IC). In this study, we examined the association between statin use and BPS/IC using a population-based study. Subjects and Methods: This case-control study used the Taiwan Longitudinal Health Insurance Database. In total, 815 female subjects with BPS/IC and 4075 randomly selected female controls were included. We used a conditional logistic regression to compute the odds ratio (OR) for having previously used statins between cases and controls. Results: A conditional logistic regression analysis showed that the OR of prior statin users for cases was 1.52 (95% confidence interval (CI): 1.19-1.94) compared to controls after adjusting for diabetes, hypertension, coronary heart disease, obesity, chronic pelvic pain, irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, depression, panic disorder, migraines, sicca syndrome, allergies, endometriosis, and asthma. Furthermore, adjusted ORs of regular and irregular statin use for cases were 1.58 (95% CI: 1.20-2.08) and 1.53 (95% CI: 1.02-2.31), respectively, compared to controls. Conclusion: We concluded that there was an association between statin use and BPS/IC. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Sandwich structures with a soft core typically exhibit multiple deformation modes such as bending, twisting and compression when subjected to transverse loads. Compressive behavior of soft core significantly affects the structural response, which is usually neglected in conventional plate theories. Additionally, conventional plate theories do not take into account transverse shear stress continuity. In order to address this concern and precisely characterize the characteristics of arbitrary multilayer laminated structures, a novel electromechanical coupled finite element model is developed. This model is based on a compressible layerwise third-order shear deformation theory with a soft core. Notably, the proposed model theory requires only twelve degrees of freedom for each quadratic element node. The accuracy of the model is validated first. Afterwards, several numerical investigations are carried out for piezolaminated sandwich structures with different width-to-thickness ratios, reinforcement angle and skew angle. The results demonstrate the applicability of the current model in predicting the behavior of laminated sandwich plates. [ABSTRACT FROM AUTHOR]

Many studies have shown that a positive attitude or beliefs towards life are associated with health. This study aims to investigate the predictors associated with self-reported health and to exam the impact of self-reported health towards negative feelings in the general population. Three latent variables (healthy food, self-health, and negative feeling) were constructed to investigate the relationship between self-reported health and people's negative feeling. [Extracted from the article]

To describe the trajectory of self-perceived health, use of hypnotic drugs, and total health care costs among patients with a reported diagnosis of anxiety disorders. Among anxiety patients exhibiting higher comorbidity scores (>11), our model predicted that using hypnotics might save total health care costs comparing patients not being prescribed when holding other variables constant. [Extracted from the article]

A procedure is proposed to analyze the structural failure of a composite wind blade subjected to quasi-static loads. The structural failure of a wind blade under extreme wind loads which can be treated as quasi-static loads is an important issue to be tackled when assessing the reliability of a wind turbine. In the proposed structural failure analysis procedure, the geometrically nonlinear finite element (FE) method together with several phenomenological failure criteria is used to investigate the possible failure modes such as incipient buckling, interfacial debonding, and first-ply failure of the blade via an incremental loading approach. The failure loads and locations associated with the possible failure modes for a number of small wind blades with different structural configurations are determined to study the appropriateness of the failure criteria. Static tests of several small glass-fabric composite wind blades were conducted to validate the suitability of the proposed procedure. It has been shown that the experimentally and theoretically predicted failure processes of the wind blades are in good agreement. The applications of the proposed procedure are demonstrated by means of a numerical example in which the failure process of a wind blade under quasi-static wind loads is simulated. [ABSTRACT FROM AUTHOR]

Infrared thermography and pressure measurements are presented of the detailed local Nusselt number ( Nu 0 ) distributions over top-endwall and the associated pressure drop coefficients ( f 0 ) of a stationary two-pass 90-deg ribbed parallelogram channel. The parallelogram cross-section has equal adjacent sides of 45.5 mm in length (aspect ratio = 1) and channel hydraulic diameter of 32.17 mm. The rib pitch-to-height ratio, rib width-to-height ratio and rib-height to channel-height ratio are 10, 1 and 0.1, respectively. It is aimed at exploring the effects of Reynolds number, Re = 5000–20,000, on Nu 0 and regionally averaged ( Nu ‾ 0 ) Nusselt numbers along the ribbed inlet/outlet legs and over the bend. To gain insight into the heat transfer augmentation mechanisms, the PIV measurements were also performed for correlating the fluid flow and heat transfer characteristics in the two legs and inside the bend at Re = 10,000 in terms of the streamwise main flow and cross-sectional secondary flow, turbulent kinetic energy as well as spanwise and streamwise Nu 0 and Nu ‾ 0 . It is found that the flow dynamic mechanisms responsible for the rib-top and mid-rib heat transfer enhancement are different for the inlet and outlet passes. The presences of a skewed high Nu 0 streak between the last inlet-leg rib and the bend as well as two high Nu 0 zones inside the bend are the new found features lacking in the corresponding two-pass 90-deg ribbed square channel. In addition, simple correlations of Nu 0 and f 0 with Re are acquired. Thermal performance factors are about 66% and 28% higher than the previous reported smooth-walled counterpart at Re = 5000 and 20,000, respectively. They are further compared with those of the corresponding square channels available from the literature. [ABSTRACT FROM AUTHOR]

This paper aims to measure and simulate the warpages of 3D through-silicon via (TSV) die-stacked dynamic-random-access-memory (DRAM) packages during the manufacturing process. The related die stresses and keep-out zone (KOZ) for the stacked dies in the packages at room temperature are further calculated with the validated simulation model. The out-of-plane deformations (or warpages) of the packages from the full-field shadow moiré are documented under temperature loading and found consistent with those from finite-element method (FEM). The results of the stresses and KOZs at the proximity of a single TSV for each die in the package at room temperature are presented. It is found that the sizes of KOZs in four-die stacked DRAM packages with and without epoxy molding compound (EMC) at room temperature are dominated by the horizontal pMOS transistors and more than double the size in wafer-level die. The sizes of KOZs at each die are similar in this four-die stacked DRAM package, even though the stresses at each die are apparently different. [ABSTRACT FROM AUTHOR]

Approximately 33% of stroke survivors suffer depression and depression is associated with disability, poor quality of life and mortality. We examined association between depression and healthcare expenditures among stroke survivors. Conclusions Depression in stroke survivors was associated with increased prescription expenditure, but not other expenditures. [Extracted from the article]

This method is termed Terminal branches portal vein Embolization Liver Partition Planned hepatectomy (TELPP). Of the 11 patients with hepatectomy, right hemihepatectomy(n=2), extended right hemihepatectomy (n=5), right trisecmentectomy(n=2), extended left hemihepatectomy (n=1) and left trisecmentectomy(n=1). It has the merit of ALPPS as extraordinarily rapid increasement of FLR volume, yet the morbidity and mortality is much lowe, as only single surgical operation is required. [Extracted from the article]

This method is termed Terminal branches portal vein Embolization Liver Partition Planned hepatectomy (TELPP). Of the 11 patients with hepatectomy, right hemihepatectomy(n=2), extended right hemihepatectomy (n=5),right trisecmentectomy(n=2), extended left hemihepatectomy (n=1) and left trisecmentectomy(n=1). It has the merit of ALPPS as extraordinarily rapid increasement of FLR volume, yet the morbidity and mortality is much lowe, as only single surgical operation is required. [Extracted from the article]

Microstructural characterization of deformation-induced martensite in its early stage of formation has been performed in an ultrafine-grained (UFG) medium Mn advanced high strength steel (AHSS). By using field emission scanning electron microscope (FESEM) and electron backscattered diffraction (EBSD), the nucleation site of deformation-induced martensite has been studied. Grain sizes, Schmid factors and aspect ratios of the parent austenite grains of deformation-induced martensite were measured in order to know their influence on the formation of deformation-induced martensite. Orientation relationship between deformation-induced martensite and its parent austenite has also been analyzed. Discussion on the effect of microstructural parameters on the formation of deformation-induced martensite in AHSS is given. [ABSTRACT FROM AUTHOR]

To explore the mechanical behavior and microstructure evolution of nanostructured bainite under deformation at high strain rates (> 10 3 s − 1 ), split Hopkinson pressure bar experiments were conducted. It was found that nanometer-sized twinning occurred in both blocky austenite and film austenite. In the former case, the intersections of different twin variants brought about strain-induced α’-martensite, while in the latter case, the lamellar twinned structures were occasionally accompanied by a small amount of ε martensite. It is concluded that twinning occurs first in blocky austenite, enhancing the initial work-hardening; subsequent twinning takes place in film austenite, promoting further straining. [ABSTRACT FROM AUTHOR]

In this work, a possible cause of the extraordinary low impact toughness of nanostructured bainite has been investigated. The microstructure of nanostructured bainite consisted chiefly of carbide-free bainitic ferrite with retained austenite films. X-ray diffractometry (XRD) measurement indicated that no retained austenite existed in the fractured surface of the Charpy-impact-tested specimens. Fractographs showed that cracks propagated mainly along bainitic ferrite platelet boundaries. The change in microstructure after impact loading was verified by transmission electron microscopy (TEM) observations, confirming that retained austenite was completely transformed to strain-induced martensite during the Charpy impact test. However, the zone affected by strained-induced martensite was found to be extremely shallow, only to a depth of several micrometers from the fracture surface. It is appropriately concluded that upon impact, as the crack forms and propagates, strain-induced martensitic transformation immediately occurs ahead of the advancing crack tip. The successive martensitic transformation profoundly facilitates the crack propagation, resulting in the extremely low impact toughness of nanostructured bainite. Retained austenite, in contrast to its well-known beneficial role, has a deteriorating effect on toughness during the course of Charpy impact. [ABSTRACT FROM AUTHOR]