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关键词： OPCAB   CAD   air pollution   PM2.5   LVEF  

摘要： Background: The survival benefit of surgical revascularization in multivessel coronary artery disease is well understood, though it can be modified by left ventricular dysfunction. Chronic exposure to air pollutants has gained more attention recently as a possible non-traditional morbidity and mortality cardiovascular risk factor. This study identified possible 5-year mortality risk factors related to postoperative left ventricular performance, including air pollutants. Patients: There were 283 patients (244 (86%) males) with a median age of 65 (60-70) years enrolled in the retrospective analysis. All patients were referred for off-pump coronary artery revascularization due to chronic coronary syndrome that presented as a multivessel coronary artery disease. They were divided into three groups depending on the postoperative course of left ventricular fraction (LVEF 50% or more (169 patients), LVEF between 41 and 49% (61 patients), and LVEF 40% or less (53 patients)). Results: The overall survival rate was 84% (237 patients) in a median follow-up time of 5.3 (4.8-6.1) years. The median (Q1-Q3) chronic air pollution exposures for the analyzed group were 19.3 (16.9-22.4) mu g/m(3) for fine particles such as PM2.5, 25.8 (22.5-29.4) mu g/m(3) for coarse particles such as PM10, and 12.2 (9.7-14.9) mu g/m(3) for nitric dioxide (NO2). The mortality in the first group (LVEF at least 50%) was 23 (13.6%), in the second group (LVEF 41-49%) was 9 (15%), and in the third group (LVEF 40% or less) was 14 (26%). The multivariable regression analysis for the five-year mortality risk in the first group revealed the predictive value of dyslipidemia (HR: 3.254, 95% CI: 1.008-10.511, p = 0.049). The multivariable regression analysis for five-year mortality risk in the second group revealed the predictive value of dyslipidemia (HR: 3.391, 95% CI: 1.001-11.874, p = 0.050) and PM2.5 (HR: 1.327, 95% CI: 1.085-1.625, p = 0.006). In the third group (severely decreased LVEF), chronic PM2.5 expo

摘要： Report on a 2023 computer-aided design meeting held by the Computer History Museum

关键词： CAD/CAM composite   dental bleaching   H2O2   mechanical properties   phthalimidoperoxycaproic acid   surface properties  

摘要： The study aimed to investigate the influence of H2O2-based and H2O2-free in-office bleaching on the surface and mechanical attributes of CAD/CAM composite blocks. CAD/CAM composite blocks from five different composite materials (CC1, CC2, CC3, CC4, and CC5) were randomly divided into two groups according to bleaching application (H2O2-based and H2O2-free). The surface topography, morphology, nanohardness, elastic modulus, flexural strength, and fracture toughness were measured. A paired and unpaired sample t-tests gauged the effect of pre- and post-bleaching on the substrates. The estimated mean differences (before-after bleaching) suggested an increase in surface roughness for two materials CC2 and CC4, and a significant decrease in nanohardness for material CC4 and in elastic modulus for materials CC2 and CC4 with H2O2-based bleaching, whereas H2O2-free bleaching resulted in changes compatible with no change in these properties. Flexural strength and fracture toughness showed no evidence of changes, irrespective of the bleaching gel used. Scanning electron microscopic analysis revealed erosive effects and micropore formation due to H2O2-based bleaching. H2O2-based bleaching deteriorates the surface of CAD/CAM composite materials while H2O2-free bleaching gel had an insignificant effect on both surface and bulk properties. The clinician should carefully evaluate the potential effects of H2O2-based bleaching on the surface properties of CAD/CAM composites.

关键词： Air-sea momentum flux   Light wind conditions   CAM6   Online and offline test   DISO   Simulation performance  

摘要： Parameterizing momentum flux under light wind conditions poses a challenge in the development of air-sea flux parameterizations. In this study, we evaluated some modifications to air-sea momentum flux parameterizations under light wind conditions, including surface layer effects (smooth flow and capillary waves), gustiness effects, and non-local effects. By coupling these modifications into the Community Atmosphere Model version 6 (CAM6), we conducted six sensitivity experiments to assess their direct impact on air-sea momentum flux under light wind conditions and their indirect impact on the simulation performance in low-latitude sea areas. During the iteration process in model, the complex negative feedback between wind speed and momentum flux led to differences in momentum flux patterns among experiments in the three key sea areas and inconsistency between offline and online test results. Based on the comprehensive evaluation metric Distance between Indices of Simulation and Observation (DISO), we assessed the simulation performance of experiments in the entire low-latitude sea area, the three key sea areas, and under light wind conditions. The discrepancy in the 10-m wind speeds deviation between light wind conditions and medium to strong wind conditions led to a reversal in the ranking of the simulation performance of the six experiments under light wind conditions compared to the entire low-latitude sea area.

关键词： 3D printed   computed tomography   facial scanning   ocular prosthesis   UV printing  

摘要： There are various techniques available for constructing a custom ocular prosthesis. The present technique report describes a digital workflow for constructing an ocular prosthesis using computed tomography integrated with digital technologies. The outer region of the healthy eyeball was segmented to produce the top surface of the prosthesis, while the contour and bottom surface were segmented from the tissue bed of the anophthalmic socket. The iris position was determined by tracing the optical nerve and confirmed by superimposing the patient's facial scan onto the soft tissue model of the computed tomography. Using these parameters, a standard tessellation language file for the ocular prosthesis was generated and 3D printed. The iris was then printed via UV technology using digital photographs of the patient's contralateral eye;characterization of the sclera and the final layer of clear acrylic resin were done conventionally.

关键词： zirconia-reinforced lithium silicate   CAD/CAM materials   glass-ceramics   flexural strength   surface treatment   hydrofluoric acid  

摘要： The aim of this investigation was to evaluate the effect of etching protocols on bond strength, surface roughness, and mechanical properties of a zirconia-reinforced lithium silicate (ZLS) CAD/CAM-ceramic. In total, 100 bars (ISO 6872), 75 plaques, and 25 cubes were cut from ZLS blocks(Vita Suprinity (R)). The surfaces were standardized, crystallized and divided into five groups: 1. control (no/treatment-C), 2. 5%-Hydrofluoric-acid (HF)/20 s (HF5%20s), ***5%60s, ***10%20s, and ***10%60s. Flexural strength (FS) (three-point bending test, 1 mm/min), roughness (Pa), and micro-shear bond-strength (mu SBS) tests were performed. The data were statistically analyzed with one-way ANOVA, Tukey's test (p < 0.05) and Weibull (FS data). C showed higher Pa (1.176 +/- 0.370 m) than HF10%60s (0.627 +/- 0.236 mu m) and all other groups. Groups C and 20 s showed the most irregular surface patterns. The FS results were not influenced by etching protocols, while the Weibull modulus was, with the 5%HF groups being the most reliable (m: 5.63/6.70), while C and HF10%60s (m: 2.78/2.73) were the least reliable. All fractures originated from surface defects on the treated side of specimens. The 5%HF groups showed higher mu SBS (20 s: 21.35 +/- 4.70 MPa;60 s: 23.50 +/- 4.27 MPa) than the 10%HF groups (20 s: 14.51 +/- 2.47 MPa;60 s: 16.54 +/- 3.12 MPa) and C (6.46 +/- 2.71 MPa). The most prevalent failure pattern was "mixed" for etched groups, and "adhesive" for C. Etching protocols affect the evaluated properties by roughening materials' surface and, in some cases, regularizing surface defects. The best overall outcomes were achieved when applying 5%HF.

关键词： DNA   Pathogens   Genomics   Bioinformatics   Sequential analysis   Pandemics   Hamming distances   DNA detection and classification   content addressable memory   approximate search   resistive memory   memristors  

摘要： We propose a novel resistive edit distance-tolerant content addressable memory for computational genomics applications, particularly for detection and identification of pathogens ofpandemic importance. Unlike state-of-the-art approximate search solutions that tolerate small number of replacements between thequery pattern and the stored data, DIPER tolerates insertionsand deletions, ubiquitous in genomics. DIPER achieves up to1.7xhigherF1score for high-quality DNA reads and up to 6.2xhigherF1score for DNA reads with 15% error rate, comparedto state-of-the-art DNA classification tool Kraken2. Simulated at500 MHz, DIPER provides 910xaverage speedup over Kraken2

关键词： carbohydrates   cellulose   crassulacean acid metabolism   hydrogen isotope fractionation   Oryza sativa   photosynthesis   Quercus   sugar  

摘要： Measurements of stable isotope ratios in organic compounds are widely used tools for plant ecophysiological studies. However, the complexity of the processes involved in shaping hydrogen isotope values (delta H-2) in plant carbohydrates has limited its broader application. To investigate the underlying biochemical processes responsible for H-2 fractionation among water, sugars, and cellulose in leaves, we studied the three main CO2 fixation pathways (C-3, C-4, and CAM) and their response to changes in temperature and vapor pressure deficit (VPD). We show significant differences in autotrophic H-2 fractionation (epsilon(A)) from water to sugar among the pathways and their response to changes in air temperature and VPD. The strong H-2 depleting epsilon(A) in C-3 plants is likely driven by the photosynthetic H+ production within the thylakoids, a reaction that is spatially separated in C-4 and strongly reduced in CAM plants, leading to the absence of H-2 depletion in the latter two types. By contrast, we found that the heterotrophic H-2-fractionation (epsilon(H)) from sugar to cellulose was very similar among the three pathways and is likely driven by the plant's metabolism, rather than by isotopic exchange with leaf water. Our study offers new insights into the biochemical drivers of H-2 fractionation in plant carbohydrates.

关键词： Health risks  

摘要： Purpose: Vibrations encountered in variant environmental conditions can lead to fatigue, discomfort, and health risks to individuals who come into contact with them. Understanding the effect of vibration on human subjects of different masses and anthropometric dimensions is crucial for ergonomic designing and minimizing the potential adverse effects. Materials and methods: This study presents a comparative study to evaluate the impact of these vibrations on Indian human subjects with masses of 54 kg and 76 kg, using a four-layer CAD model with the help of FEM simulations to analyze the seat-to-head (STHT) and feet-to-head (FTHT) transmissibility for vibrations within the frequency of 0–20 Hz range and acceleration of different intensities, i.e., 0.5 m/s2, 1 m/s2, and 1.5 m/s2. The four-layer CAD model considered four anatomical layers of a human subject including skin, organs, bones, and muscles;each layer was assigned appropriate material properties as per the characteristics of a human tissue. Results: There were significant differences in the STHT and FTHT for both human subjects, and the pattern of transmissibility varied across the frequency range and was also influenced by the levels of acceleration. The higher level of acceleration results in an increase in transmissibility, and the increase in the mass of human subjects also shows the increase in the value of transmissibility that represents the pronounced impact of vibrations on human subjects. Conclusion: The findings indicate that body mass has a major impact on vibration transmission. The relationship between body mass and transmissibility, on the other hand, is complicated and can change depending on the vibration transmission channel. These findings add to the increasing body of information in the field of human vibration exposure and may have implications for building more personalized seating and ergonomic solutions for people with varied body types. More study is needed to go deeper into the underly