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关键词： natural gas engines   valve lift profile   multi-objective optimization   impact-free cam   valve motion verification  

摘要： The valve lift profile plays a crucial role in the gas exchange process of natural gas engines, as well as in the operational stability of the valve mechanism. Through optimization and design of the valve lift profile, it is possible to effectively reduce engine gas exchange loss, enhance engine power output, and improve the operational stability of the valve mechanism. This study establishes a simulation model for a natural gas engine, which is validated against experimental data. The impact of various parameters on engine performance is explored using a parametric method and experimental design. The paper focuses on optimizing the valve lift profile at a typical operating point, with targets of minimizing brake-specific fuel consumption and NOx emissions. The non-dominated sorting genetic algorithm was employed to optimize the valve lift profile. Given that the optimized lift curve alters the original kinematic characteristics, an impact-free function cam design method was adopted to perform the forward design of the optimized curve, followed by a comprehensive valve motion verification. The results show that the fullness coefficient of the optimized exhaust valve lift profile increased from 0.609 to 0.637, and the fullness coefficient of the intake valve lift profile improved from 0.578 to 0.608. The larger fullness coefficient indicates improved engine gas exchange performance. At 90.9% load, the brake-specific fuel consumption of the natural gas engine decreased by 2.76%, and NOx emissions were reduced by 22.93%. The valve lift profiles designed using the cam method with the impact-free function achieved third-order continuity in lift, velocity, and acceleration. This ensures smoother operation of the engine valve mechanism and prevents abnormal vibration.

关键词： smokeless tobacco   CAD/CAM   ceramics   color stability   black   shammah   DZRT snuff  

摘要： INTRODUCTION This in vitro study investigated the effects of two types of smokeless tobacco (ST), black shammah and DZRT snuff, on the mean color stability (AE**) and contact profilometry results (surface roughness [Ra]) of five Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM) ceramic materials: feldspathic ceramics (VITABLOCS TriLuxe Forte and Mark II), multilayer zirconia (Ceramill Zolid PS), zirconia-reinforced lithium silicate (VITA Suprinity), and lithium disilicate glass ceramic (IPS *** CAD). METHODS A total of 100 specimens of VITABLOCS Mark II, Ceramill Zolid Multilayer PS, VITA Triluxe Forte, IPS *** CAD, and VITA Suprinity were divided into two ST exposure subgroups, the black shammah and DZRT snuff groups. Samples underwent daily tobacco staining, thermocycling (5-55 degrees C), and brushing simulation (10000 cycles). Color parameters (L*, a*, and b*) were measured by using a spectrophotometer (VITA Easyshade (R) Compact) at baseline and at one, two, and four weeks. AE** was calculated by employing the CIEDE2000 formula. Assessments with the VITA classical shade guide were employed to record shifts in the lightness/darkness of samples. Ra (& micro;m) was assessed via contact profilometry at the end of the study. Statistical analyses included the Kruskal-Wallis, Mann-Whitney U, and chi-squared tests, with significance set at p<0.05. RESULTS After four weeks of immersion in DZRT snuff, IPS *** CAD showed the highest AE** (6.718) among the tested materials, whereas Ceramill Zolid PS and VITABLOCS Mark II exhibited the lowest AE** values (0.614-1.075) across ST types and durations. Significant AE** differences were observed among ceramics (p<0.05), staining solution types (p<0.001 for IPS *** CAD at four weeks), and immersion times (p<0.001). Assessments with the VITA classical shade guide showed that shades darkened significantly (p<0.05) after 2-4 weeks (p<0.05), with the prevalence of the A2 shade decreasing from 62% to 42% after e

关键词： aneurysm   arteries   ischemic stroke   risk factor  

摘要： BACKGROUND:Cervical artery dissection (CeAD) may result in dissecting aneurysm (DA) formation. We aimed to characterize risk factors and clinical outcomes associated with DA in a large, international CeAD ***:We performed a secondary analysis of STOP-CAD (Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection), an international, multicenter, retrospective cohort. Patients with spontaneous CeAD were assessed for DA at baseline and de novo DA formation. Significant covariates in univariable analysis were included in multivariable regression models aiming to identify factors associated with DA formation. Logistic regression and Cox proportional hazards models evaluated the association of DA with ischemic and hemorrhagic ***:Among 4008 patients with CeAD, 546 (13.6%) had a DA at baseline, and 221/2938 (7.5%) patients developed a de novo DA during follow-up, of which 172/221 (78.2%) were detected in the first 180 days. Patients with DA had a mean age of 47 years, and 383 (49.9%) were women. Baseline or de novo DA was associated with a history of connective tissue disorder (adjusted odds ratio [aOR], 2.02 [95% CI, 1.22-3.36]), fibromuscular dysplasia (aOR, 1.69 [95% CI, 1.28-2.25]), and multiple vessel dissection (aOR, 1.53 [95% CI, 1.19-1.98]). Lower odds of DA were seen in Hispanic ethnicity (aOR, 0.64 [95% CI, 0.43-0.97]) and ischemic stroke presentation (aOR, 0.41 [95% CI, 0.34-0.49]). Fibromuscular dysplasia was associated with de novo DA formation (aOR, 2.30 [95% CI, 1.52-3.49]). DA was not associated with ischemic stroke (hazard ratio, 0.71 [95% CI, 0.44-1.16];P=0.173) or intracranial hemorrhage (HR, 1.09 [95% CI, 0.42-2.84];P=0.86) by day ***:DAs are relatively common manifestations of CeAD, typically occurring within 6 months of CeAD diagnosis. DA was not associated with an increased risk of subsequent ischemic stroke or intracranial hemorrhage.

关键词： Metal additive manufacturing   Analytical heat transfer model   CAD-Simulate-Print   Scanning strategy  

摘要： A lack of direct integration between the digital part geometry, defined in a computer-aided design (CAD) file, and the computer-based simulation models is the key obstacle to the selection of process parameters based on scientific understanding for 3D printing of metallic parts. We present here a novel CAD-Simulate-Print framework by enabling a part-scale 3D analytical heat conduction model to directly consider the digitized part geometry from a CAD model and generate multiple possible scan paths for a range of user-defined process conditions. The computed transient temperature field and melt pool dimensions for multiple possible scanning strategy are examined systematically to help select an appropriate printing condition with the minimum susceptibility to lack-of-fusion porosity and part distortion. The computed results showed a fairly reliable agreement with the experimentally measured results. Overall, the proposed CAD - Simulate-Print framework has exhibited a potential to provide a scalable approach for additive manufacturing process design.

关键词： CADASIL   Tocopherol   Cerebral small vessel disease   Neuroprotection   Vitamin E   Bayesian model   Clinical trial   MRI markers   Stroke   Cognition   Disability  

摘要： Background Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADA-SIL) is the most common monogenic small vessel disease, causing recurrent stroke and progressive cognitive decline, with no disease-modifying treatment available. Tocotrienols, members of the vitamin E family, have demonstrated neuroprotective effects in preclinical studies. We evaluated the efficacy and safety of a tocotrienolrich vitamin E complex (HOV12020) in patients with CADASIL. Methods In this randomised, double-blind, placebo-controlled trial, 51 patients (median age (range): 58 years (43-73 y), male (n = 24, 47%)) with genetically confirmed CADASIL were assigned (1:1) to receive HOV12020 or placebo for 24 months. The primary endpoint was treatment failure, defined as any stroke occurrence, disability progression, or cognitive decline, and was analysed within a Bayesian framework to estimate the probability of treatment benefit. The secondary endpoints included the time to the first failure event, changes in clinical and cognitive scores, and safety. Exploratory MRI endpoints were analysed using quantile regression with Wilcoxon rank-sum sensitivity tests. EudraCT 2019-002867-23;*** NCT04658823. Findings Patients were enrolled in the trial between 15/01/2021 and 11/02/2022. Treatment failure occurred in 68.0% of patients in the HOV12020 group and 61.5% in the placebo group, both exceeding the 40% placebo event rate that was initially expected. Bayesian analysis indicated a low posterior probability of benefit, meeting the predefined futility criteria. No significant differences were observed in the secondary endpoints or exploratory MRI measurements. HOV12020 was well tolerated, with an excellent safety profile and no excess of adverse events. Interpretation HOV12020 did not reduce clinical progression in CADASIL over 24 months. Bayesian analysis confirmed futility, suggesting that tocotrienol-rich vitamin E is unlikely to confer benefi

摘要： Consistent with herding behavior, prior research generally finds little to no evidence of market reactions to the initiation of critical audit matter (CAM) disclosures in the audit report. We expand upon recent work to identify instances of anti-herding behavior in CAM disclosures, which we capture by examining topically distinct and textually dissimilar CAM disclosures. Consistent with anti-herding behavior, we first document that first-time CAM disclosures with these attributes result in greater equity market responses surrounding the release of the audit report, especially when accompanied by a weaker information environment, greater disclosure specificity, and heightened client litigation risk. Additional evidence indicates that these types of anti-herding CAM disclosures may create confusion among some market participants. We provide further support that distinct and dissimilar CAM disclosures reduce the information gap between auditors and investors by showing that these measures provide explanatory power in an audit fee model. Lastly, we document decreases in each of our measures from the year of CAM implementation to the second year, suggesting a trend toward boilerplate disclosures. Overall, our results provide novel evidence that CAM disclosures that "stick out" from the herd provide information to financial statement users and thus reduce the information gap between auditors and financial statement users.

关键词： bevel   butt joint   CAM unit   chamfer   composite resin   lithium disilicate   onlay  

摘要： Objective: To evaluate the marginal adaptation and margin trueness of lithium disilicate glass-ceramic (LDS) and glass-filler reinforced composite resin (CR) onlays fabricated using three different finish lines and two chairside CAM units (4- and 5-axis).
Methods: LDS (*** CAD) and CR (Tetric CAD) onlays were fabricated on butt joint, chamfer, and bevel finish lines using 4-axis (CEREC MC XL) and 5-axis (Programill One) chairside CAM units (N = 120). Onlays were scanned for margin trueness and marginal adaptation analyses. Data were analyzed with three-way ANOVA and Tukey B post hoc test (alpha = 0.05). Results: A significant interaction was found among finish line, material, and CAM unit for marginal adaptation and margin trueness (p < 0.001). Bevel had the highest marginal adaptation;chamfer the lowest. Butt joint showed the highest margin trueness;bevel the lowest. CR onlays had better marginal adaptation than LDS with bevel finish lines, regardless of CAM unit. Overall, 5-axis CAM units yielded better margin trueness. Conclusions: Finish line design, restorative material, and CAM unit affected the marginal adaptation and margin trueness. The bevel finish line yielded the highest marginal adaptation and the chamfer the lowest, regardless of material or CAM unit. Conversely, the butt joint showed the highest margin trueness, and the bevel the lowest.

关键词： catalogs   cosmology: observations   galaxies: clusters: general   galaxies: elliptical and lenticular, cD   gravitational lensing: weak  

摘要： We construct samples of optically selected clusters and photometric luminous red galaxies (LRGs) from the Hyper Suprime-Cam Subaru Strategic Program final-year dataset covering similar to 1200 deg(2). The cluster catalogs extend out to a redshift of 1.38 and contain more than 10000 clusters with richness larger than 15, where the richness is defined to be a membership probability weighted number of galaxies above the stellar masses of approximately 10(10.2) M-circle dot The total number of probable red cluster member galaxies in these clusters is more than 6 x 10(5). Photometric redshifts of the clusters are shown to be precise with a scatter better than similar to 0.01 for a wide redshift range. We detect stacked weak-lensing signals of clusters out to a redshift of 1, and use them to update constraints on the mass-richness relation. Our catalog of about 6 million photometric LRGs extends to a redshift of 1.25, and has a photometric redshift scatter of better than similar to 0.02 for the redshift range between 0.4 and 1.0.

关键词： Hepato-pancreato-biliary surgery   Intraoperative navigation   Three-dimensional imaging   Computer-aided design   CAD   Surgical education   Anatomical visualization   Robotic surgery   Robotic pancreatectomy  

摘要： Background In hepato-pancreato-biliary (HPB) surgery, precise anatomic understanding is *** Hepatobiliary Pancreat Surg. 23:145-154;2.J Hepatobiliary Pancreat Sci. 30:851-862;In Japan, advanced HPB board certification requires preoperative schema drawing.3.J Hepatobiliary Pancreat Sci. 24:252-261 Although three-dimensional (3D) imaging improves preoperative recognition,*** Gastroenterol Surg. 6:190-196;*** Surg Oncol. 32:3539-3543;*** Surg Oncol. 31:6567-6568;no widely adopted system exists for real-time intraoperative *** Surg. 271:e4-e7;*** J Comput Assist Radiol Surg. 20:117-129;*** Res Pract. 2021:9621323;At the authors' institution, schematic diagrams have been used, but they are time-consuming and limited in detail. To overcome these limitations, the authors developed a simple, low-cost intraoperative 3D navigation method using free computer-aided design (CAD) applications. Methods The authors analyzed 32 HPB cases managed between January and August 2025. Computed tomography (CT) data were reconstructed into 3D images using REVORAS (Ziosoft Inc., Tokyo, Japan). Based on these images, schematic diagrams were created with Procreate (Savage Interactive Pty Ltd., Australia), and CAD models were generated with Fusion 360 (Autodesk Inc., San Francisco, CA, USA) and Shapr3D (Shapr3D Zrt., Budapest, Hungary). The creation times were measured and compared. Results Surgical approaches included open (n = 14), robotic (n = 16), and laparoscopic (n = 2) procedures comprising pancreatic (n = 18), hepatic (n = 13), and sarcoma (n = 1) resection. Both schematic diagrams and CAD models were created in all cases. The median creation time was significantly shorter for CAD models (7 min 25 s) than for diagrams (19 min 48 s) (p < 0.01). The CAD models enabled real-time anatomic sharing via tablets with TilePro integration in the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA, USA). Conclusions Intraoperative CAD-based navig