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LCOS) is a dangerous postoperative complication in patients with acute type A aortic dissection (ATAAD). This study aims to develop and evaluate a nomogram model that can reliably identify risk variables for postoperative LCOS in elderly patients suffering from ATAAD. PATIENTS AND METHODS: In this retrospective study, a total of 310 elderly patients with ATAAD admitted to Fujian Medical University Union Hospital were included and categorized into the LCOS and non-LCOS groups. Stepwise logistic regression was used to analyze independent predictors of LCOS, and a nomogram was constructed. The best clinical decision points were found using decision analysis and a clinical impact curve. RESULTS: Postoperative LCOS occurred in 22 (7.1%) of elderly patients with ATAAD. Independent risk factors for postoperative LCOS were age, smoking history, aortic cross-clamp (ACC), coronary heart disease (CHD), and preoperative shock. The nomogram constructed based on the identified risk factors showed good performance. CONCLUSIONS: Our results suggest that preventive treatment can be administered when needed when the risk of LCOS in older patients with ATAAD after surgery is >60%. This study contributes to developing a methodology that may improve therapeutic decision-making in older patients and provides insights for assessing the risk of LCOS. [ABSTRACT FROM AUTHOR]

This work aims to investigate the effects of calcium on the performances of metakaolin-based geopolymer with the aid of a combination of the experiment study and molecular dynamics simulation. These impacts were comprehensively characterized by fresh properties through setting time and consistency of paste with calcium oxide (CaO) partial substitution, while the hardened properties were conducted via compressive strength and elasticity modulus tests. The microstructural characteristics of reaction products were analyzed by X-ray diffraction (XRD), thermogravimetric differential thermal analysis (TG-DTG), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET) method. Moreover, various structures of sodium aluminate silicate hydrate (N─ A─ S─ H), calcium aluminate silicate hydrate (C─ A─ S─ H), and five types of geopolymer gels models with increasing calcium content were established and optimized by molecular dynamics simulation. The results showed that the workability of paste decreased with the increase in calcium content, while there was a threshold for mechanical properties at all ages. The products of geopolymer with calcium composite incorporation inclusion were mainly amorphous phases of N(C)─ A─ S─ H containing large amounts of calcite, while even Ca(OH)2 and unreacted CaO could be found in a high-calcium system with higher crystallinity. The coexistence of gels increased compactness and also formed a relatively denser network structure with many mesopores, but poor pore structure caused by unacceptable polymerization degree and bound water consumption of hydration products occurred when the CaO replacement ratio reached 20%. Acceptable agreement between the simulations and experimental results was obtained with a significant decrease in the bond lengths of Si─ O and Ca─ O. Overall, the reaction mechanism of calcium in the system was innovatively revealed through the establishment of a macroscopic properties–microstructures–atomic model (multiscale) relationship. [ABSTRACT FROM AUTHOR]

A basic property of endothermic thermoregulation is the ability to generate heat by increasing metabolism in response to cold ambient temperatures to maintain a stable core body temperature. This process, known as cold-induced thermogenesis (CIT), has been measured in humans as early as 1780 by Antoine Lavoisier, but has found renewed interest because of the recent 'rediscovery' of thermogenic, cold-activated brown adipose tissue (BAT) in adult humans. In this review, we summarize some of the key findings of the work involving CIT over the past two centuries and highlight some of the seminal studies focused on this topic. There has been a substantial range of variability in the reported CIT in these studies, from 0 to 280% above basal metabolism. We identify and discuss several potential sources of this variability, including both methodological (measurement device, cold exposure temperature and duration) and biological (age and body composition of subject population) discrepancies. These factors should be considered when measuring CIT going forward to better assess whether BAT or other thermogenic organs are viable targets to combat chronic positive energy balance based on their relative capacities to elevate human metabolism., Author(s): R J Brychta [sup.1] , K Y Chen [sup.1] Author Affiliations: (1) Diabetes, Endocrinology, and Obesity Branch, The National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes [...]

The successful synthesis of superconducting infinite-layer nickelate thin films with the highest Tc ≈ 15 K has ignited great enthusiasm for this material class as potential analogs of the high-Tc cuprates. Pursuing a higher Tc is always an imperative task in studying a new superconducting material system. Here we report high-quality Pr0.82Sr0.18NiO2 thin films with Tconset ≈ 17 K synthesized by carefully tuning the amount of CaH2 in the topotactic chemical reduction and the effect of pressure on its superconducting properties by measuring electrical resistivity under various pressures in a cubic anvil cell apparatus. We find that the onset temperature of the superconductivity, Tconset, can be enhanced monotonically from ~17 K at ambient pressure to ~31 K at 12.1 GPa without showing signatures of saturation upon increasing pressure. This encouraging result indicates that the Tc of infinite-layer nickelates superconductors still has room to go higher and it can be further boosted by applying higher pressures or strain engineering in the heterostructure films. Despite much recent effort, the highest reported Tc of the infinite-layer nickelates remains lower than 15 K. Here, the authors apply pressure to Pr0.82Sr0.18NiO2 thin films and observe a monotonic increase of Tc to 31 K at 12.1 GPa, an increase that does not level off with increasing pressure. [ABSTRACT FROM AUTHOR]

We report an unusual pressure-induced superconducting state that coexists with an antiferromagnetic ordering of Eu2+ moments and shows a large upper critical field comparable to the Pauli paramagnetic limit in EuTe2. In concomitant with the emergence of superconductivity with Tc ≈ 3–5 K above Pc ≈ 6 GPa, the antiferromagnetic transition temperature TN(P) experiences a quicker rise with the slope increased dramatically from dTN/dP = 0.85(14) K/GPa for P ≤ Pc to 3.7(2) K/GPa for P ≥ Pc. Moreover, the superconducting state can survive in the spin-flop state with a net ferromagnetic component of the Eu2+ sublattice under moderate magnetic fields μ0H ≥ 2 T. Our findings establish the pressurized EuTe2 as a rare magnetic superconductor possessing an intimated interplay between magnetism and superconductivity. Here, the authors report pressure-induced superconductivity with concomitant enhancement of antiferromagnetic transition in layered EuTe2. The superconductivity is distinctly characterized by the high upper critical fields exceeding the Pauli limit among binary tellurides, a prerequisite of the coexistence of ferromagnetism with superconductivity. [ABSTRACT FROM AUTHOR]

Among the metal hydrides, Th4H15 is the first reported superconductor with a relatively high Tc ≈ 8 K at ambient pressure. Here we report on the synthesis and characterization of a low-Tc superconducting modification of Th4H15, which is obtained via hydrogenating Th metal at 5 GPa and 800 °C by using the ammonia borane as the hydrogen source. Measurements of resistivity, magnetic susceptibility, and specific heat confirm that the obtained Th4H15 sample shows a bulk superconducting transition at Tc ≈ 6 K, which is about 2 K lower than that reported previously. Various characteristic superconducting parameters have been extracted for this compound and unusual lattice dynamics were evidenced from the specific-heat analysis. [ABSTRACT FROM AUTHOR]

Background and purpose: Hyperglycemia in acute stroke leads to poor neurological outcomes. The role of microRNA (miRNA) in hyperglycemia‐associated genes can provide new avenues for stroke prognostic applications. We aimed to identify novel genes and their regulated miRNAs that are associated with hyperglycemia‐induced unfavorable stroke outcomes and further validated in the plasma exosome. Moreover, we intended to evaluate the prognostic ability of miRNA–messenger RNA (mRNA) biomarkers in addition to using traditional risk factors. Methods: After the integration analysis of small RNA sequencing and mRNA polymerase chain reaction array, two mRNAs and six miRNAs were selected for validation in middle cerebral artery occlusion animal models and ischaemic stroke patients. Receiver operator characteristic analysis was used to determine the performance of mRNA and miRNA expression. Results: The increased Fas expression was associated with hyperglycemia after acute stroke onset in animal and human studies. In addition, Fas gene level was significantly higher in patients with an unfavorable outcome when compared with patients with a favorable outcome. The expression of Fas and miRNA hsa‐let‐7b‐5p in addition to traditional risk factors could increase the discrimination and predictive ability for poor prognosis. The higher exosomal Fas was further observed among patients with an unfavorable outcome, suggesting Fas signal transporting through exosome in the circulation system. Conclusions: Combined analyses of Fas and has‐let‐7b‐5p expression in addition to traditional risk factors are favorable prognostic biomarkers for predicting poor neurological outcomes at 3 months after stroke onset in ischaemic stroke patients. Additional studies are required to address the precise role of the apoptosis pathway in unfavorable hyperglycemia‐induced stroke outcomes. [ABSTRACT FROM AUTHOR]

Te-doped and ZnTe-doped diluted ZnSeTe samples were grown by using metal-organic chemical vapor deposition. The green lights emitted from these two samples in the photoluminescence (PL) measurement have different peak emission energies and can be attributed to different emission mechanisms. For the Te-doped sample, the PL emission band is excitation laser power independent, the lifetime of the PL emission is short, and the PL emission could be attributed to the emission originated from Te isoelectronic centers. For the ZnTe-doped sample, the energy of the green emission band is laser power dependent, the PL lifetime is much longer than the Te-doped sample, and the PL emission could be attributed to the emission from type-II ZnTe/ZnSe quantum dots. The results demonstrate that there are two different mechanisms responsible for the green PL emission in ZnSeTe system and our growth methods provide a way of selecting one of the two mechanisms for the green light emission in this system. [ABSTRACT FROM AUTHOR]

Effective equipment management is becoming one of the key factors in keeping a competitive advantage in the dynamic business environment since equipment is an important asset for manufacturing companies. Nowadays, maintenance administration has become one of the most important tasks in equipment management, particularly in manufacturing industries. Equipment management system (EMS) aims at reducing maintenance cost and production loss caused by machine breakdown. In addition, EMS can assist equipment engineers to make the right maintenance decisions at the right time, and at the right shop floor. Traditional computerized maintenance management systems (CMMS) have helped equipment engineers to deal with maintenance operations, but they lack decision support capability. In this paper, we design a data warehouse (DW) for EMS to help equipment engineers make maintenance decisions with various equipment related dimensions to improve effectiveness. A set of cubes can be built from EMS DW for the purpose of decision-making. In order to achieve a reasonable query response time under the memory space limit, a mechanism of partial materialization based on genetic algorithms (GAs) is adopted to design data cubes in the EMS DW. From the computational results the proposed GA-based approach for cube design can be applied to effectively select the appropriate multi-dimensional views for equipment management. [ABSTRACT FROM AUTHOR]

Dimensionless three-dimensional universal phase and lift force diagrams of a microbubble (or pendant drop) in static liquid on a solid surface (or orifice) are presented in this work. Microbubble dynamics has been found to play a vital role in mass, momentum, energy, and concentration transfer rates in contemporary micro- and nanosciences and technologies. In this study, dimensionless phase and force diagrams are introduced by utilizing the analytical solutions of the microbubble shape reported in the literature. It shows that phase and force diagrams can be universally specified by two dimensionless independent parameters, Bond number, and contact angle (or base radius). Based on the presence of an inflection point or neck on the microbubble surface, each diagram exhibits three regions. Growth, detachment, and entrapment of a microbubble can be described by path lines in three regions. The corresponding universal total lift forces include hydrostatic buoyancy, difference in gas, and hydrostatic pressures at the base, capillary pressure, as well as surface tension induced by the variation of circumference, which has not been treated in the literature so far. In the absence of viscous stress and Marangoni force, the total lift force equals surface tension induced by the variation of circumference. The latter can be an attaching or lifting force, depending on whether the state in the distinct regions and contact angle is less than or greater than a critical angle. The critical angle, which is slightly less than the inclination angle at the inflection point, is decreased with increasing Bond number. [ABSTRACT FROM AUTHOR]

This study evaluates the accuracy of two alternative models for the kill rate of different visual defects and the yield estimation by using large amount of practical inspection data (140 6-inch wafers containing 70 560 dies) in semiconductor manufacturing. One model assumed that the visual defects are randomly distributed on a wafer die; another model considered that clustering visual defects may occur on a wafer die. The results show that two models are both capable of predicting the yield precisely. The results also suggest that the model assuming clustering visual defects on a die is more accurate based on the analysis of Taguchi's signal-to-noise (SN) ratio. The same practices can be implemented with other types of wafer such as 8 inch and 12 inch. Precise prediction for the kill rate of different types of visual defects and the yield in the long supply of semiconductor industry is critical since the requirement of material and the reserved capacity can be largely reduced. [ABSTRACT FROM AUTHOR]

In this study, comparative corrosion protection studies of cold-rolled steel (CRS) electrodes coated with electroactive/non-electroactive epoxy thermoset (denoted as EET/NEET) composites containing dispersed reduced graphene oxide (rGO) and graphene oxide (GO) platelets are presented. All composites were obtained through the thermal ring-opening reaction of bisphenol A diglycidyl ether (DGEBA) with amino-capped aniline trimer (ACAT) or trimethylolpropane tris[poly(propylene glycol), amine terminated] ether (T-403) at a specific mixing ratio in the presence of dispersed rGO/GO were characterized Fourier Transform Infrared (FTIR) spectroscopy and Transmission Electron Microscopy (TEM). In gas permeability measurements, the GO was found to display a slightly better dispersion capability in both EET and NEET membrane than in rGO. Conductive rGO platelets were found to promote the redox behavior of EET and non-conductive GO platelets was found to depress the redox behavior of EET, as measured by electrochemical cyclic voltammetry (CV) studies. Corrosion protection of composite coatings was investigated by electrochemical corrosion measurements in saline solution. It should be noted, in the EET system, that rGO was found to exhibit better anticorrosion performance as compared to that of GO. However, in NEET system, GO was found to have better anticorrosion performance than rGO. Better anticorrosion of rGO in EET may be attributed to better synergistic effect of electro-catalytic and the oxygen barrier properties of rGO in EET. On the contrary, better anticorrosion of GO in NEET may be associated with better oxygen barrier property of GO alone in NEET than that of rGO. The passive metal oxide layer formed on the cold rolled steel (CRS) electrode induced by EET was further confirmed by Raman and Electron Spectroscopy for Chemical Analysis (ESCA). [ABSTRACT FROM AUTHOR]

Summary: Objectives: Lipodystrophies are characterized by regional or generalized loss of adipose tissue and severe metabolic complications. The role of visceral adipose tissue (VAT) in the development of metabolic derangements in lipodystrophy is unknown. The study aim was to investigate VAT contribution to metabolic disease in lipodystrophy versus healthy controls. Methods: Analysis of correlations between VAT volume and biomarkers of metabolic disease in 93 patients and 93 age/sex‐matched healthy controls. Results: Patients with generalized lipodystrophy (n = 43) had lower VAT compared with matched controls, while those with partial lipodystrophy (n = 50) had higher VAT versus controls. Both groups with lipodystrophy had lower leg fat mass versus controls (p < 0.05 for all; unpaired t‐test). In both generalized and partial lipodystrophy, there was no correlation between VAT and glucose, triglycerides or high‐density lipoprotein cholesterol (p > 0.05 for all; Spearman correlation). In controls matched to patients with generalized or partial lipodystrophy, VAT correlated with glucose (R = 0.42 and 0.36), triglycerides (R = 0.36 and 0.60) and high‐density lipoprotein cholesterol (R = −0.34 and −0.64) (p < 0.05 for all; Spearman correlation). Conclusions: In contrast to healthy controls, metabolic derangements in lipodystrophy did not correlate with VAT volume. These data suggest that, in lipodystrophy, impaired peripheral subcutaneous fat deposition may exert a larger effect than VAT accumulation on the development of metabolic complications. Interventions aimed at increasing functional subcutaneous adipose tissue may provide metabolic benefit. [ABSTRACT FROM AUTHOR]