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关键词： 人工饲料育   蚕丝针织物   机械性能   表观颜色   色牢度  

摘要： 随着人工饲料养蚕技术的逐渐推广,系统评估蚕丝织物的性能对推动该技术规模化应用具有重要意义。文章以工厂化全龄人工饲料育与全龄桑叶育精练蚕丝针织物及其对应染色针织物为研究对象,系统测试其表面形貌、透气透湿性、顶破强力、耐磨性、悬垂性、K/S值、Lab值和色牢度,重点对比两类织物的性能差异。结果表明:精练后,两类针织物的表面形貌、透气性与透湿性无显著差异;受蚕丝二级结构与结晶特性影响,饲料育针织物的顶破强力、耐磨性略低于桑叶育针织物,悬垂性稍优。染色后,两类针织物的透气性均显著下降,悬垂性与耐磨性显著提高,透湿性和顶破强力无显著变化,且二者的K/S值、Lab值和色牢度均无显著差异。研究结果明确了饲料育针织物的关键性能特征,可为人工饲料养蚕技术的推广与饲料育织物的应用提供数据支撑。

关键词： 3D printing   Antacids   Composite resins, Computer-Aided design   Surface properties   Dental materials  

摘要： Background This in vitro study aimed to evaluate the effect of simulated gastric fluid (SGF) and an alginate-based antacid on the surface roughness and color stability of two additively manufactured (AM) and one subtractively manufactured (SM) resin-based restorative materials.
Methods A total of 168 disc-shaped specimens (10x2 mm) were fabricated from two AM resin composites (Bego VarseoSmile TriniQ [AM-VS] and Saremco Crowntec [AM-C]) and one SM nano-ceramic hybrid (Voco Grandio blocs [SM-V]). Specimens were distributed into seven subgroups (n = 8) based on immersion media: distilled water (control);SGF mixed with artificial saliva (AS) at ratios of 1:1, 1:3, and 1:5;and the same mixtures with 10% alginate-based antacid (Gaviscon"). All solutions were refreshed daily and maintained at 37 degrees C with gentle agitation for 48 h. Surface roughness (Ra) was measured with a contact profilometer, and color stability (Delta Eoo) was assessed with a spectrophotometer. Data were analyzed using mixed-model ANOVA and post hoc tests (a = 0.05)
Results Immersion in SGF + AS increased Delta Eoo and Ra values in all materials compared with distilled water (p < 0.001) The highest color change was observed in AM-C at SGF+AS (1:5) (1.87 +/- 0.30), whereas SM-V showed the lowest Delta Eoo values (1.55 +/- 0.04). Surface roughness increased under acidic conditions, with AM-C exhibiting the highest Ra values (1.30 +/- 0.02 & micro;m). The alginate-based antacid significantly reduced Ra values for all materials and reduced Delta Eoo values in AM-C (1:3 and 1:5) and AM-VS (1:5) (p<.05), with selected antacid-containing subgroups showing values approaching those of the control.
Conclusions Simulated gastric fluid compromised the surface integrity and color stability of CAD/CAM resin-based restorative materials, with material-dependent differences. The addition of an alginate-based antacid mitigated these effects under selected experimental conditions, suggesting a pot

关键词： Flexural properties   Surface hardness   Milled CAD/CAM   Denture base resin  

摘要： Objective The objective of this study is to evaluate the flexural strength and surface hardness of denture base resins that have been milled using computer-aided design and computer-aided manufacturing milling (CAD/CAM) and conventional heat-polymerized denture base resins (HP). Methods Eighty samples were made using CAD/CAM resin material (Polident CAD/CAM and Interdent CC discs) and conventional heat-polymerised acrylic resin (HP) (IvoBase CAD and PMMA). Based on the denture base material, the samples were categorised into eight groups: each group (n = 10), flexural strength (n = 40), surface hardness (n = 40). Both the surface hardness and flexural strength were evaluated using the Vickers hardness test and the three-point flexure test, respectively. A statistical analysis with a significance level of alpha = 0.05 was used to analyze the data. Results Compared with HP resins, milled CAD/CAM resins demonstrated significantly higher flexural strength and surface hardness (p < 0.001). The flexural strength of MHC 72.72 +/- 5.95 is significantly lower than that of IHC 78.96 +/- 3.36, PCC 108.59 +/- 6.51, and VCC 99.88 +/- 6.05 MPa. Surface hardness is significantly lower in MHC (18.40 +/- 2.28 VHN) than in the other groups: IHC (21.30 +/- 2.40 VHN), PCC (31.07 +/- 2.07 VHN), and VCC (27.09 +/- 1.55 VHN). Conclusion Compared with heat-polymerized acrylic resin, milled CAD/CAM resins performed exceptionally well in terms of flexural and surface mechanical properties.

关键词： Scapula free flap   CAD/CAM   Mandibular reconstruction   Patient-specific implant   Free flaps   Accuracy   Microvascular transplant   Free bone transplant  

摘要： Purpose For the first time, this study explores the transfer precision of computer aided design and computer aided manufacturing (CAD/CAM) in mandibular reconstruction with scapula free flaps (SFF). Methods Patients undergoing mandibular reconstruction with SFF and patient-specific 3D-printed titanium plates were retrospectively analyzed. To assess planning accuracy, pre-and postoperative datasets were overlaid using 3D Slicer software. Specific measurements included the fit at the mandibular resection site, intersegmental gap width between scapula and mandible, scapular segment positioning, and condylar alignment. Osseous union was evaluated via postoperative computed tomography (CT) or cone beam CT, and plate-related complications were recorded clinically. Results In total 15 patients (mean age 65.7 +/- 10.0 years) were included. Postoperative scapular segment positioning showed deviations in the posterior region (basal: 6.78 +/- 3.34 mm;crestal: 7.61 +/- 3.40 mm) and anterior region (basal: 3.54 +/- 1.52 mm;crestal: 4.49 +/- 2.51 mm). Mean deviation in segmental gap width at the anterior and posterior sites ranged from 0.55 to 1.72 mm and was statistically significant at all four measurements. Mean contralateral condyle position differed significantly from the initial position (8.56 +/- 4.31 mm). Intraoral plate exposure occurred in three patients without adjuvant radiotherapy;no extraoral exposure, fractures, or loosening were observed. Non-union between the mandible and SFF was found in three patients. Conclusion As with other CAD/CAM-assisted mandibular reconstructions, SFF exhibit discrepancies between virtual planning and the postoperative outcome. The surrounding soft tissue bulk of the scapula can hinder the precise fit of cutting guides, potentially compromising reconstruction accuracy and contributing to increased deviations. Despite these challenges, CAD/CAM-assisted SFF demonstrates acceptable surgical predictability.

关键词： Radiomics   Pericoronary adipose tissue   CT-FFR   T2DM with CAD   Machine learning   SHAP  

摘要： This study aims to integrate lesion-specific pericoronary adipose tissue (PCAT) radiomics analysis with existing clinical and imaging methods under the guidance of CT-derived fractional flow reserve (CT-FFR), to develop and validate an interpretable machine learning (ML) prediction model for patients with type 2 diabetes complicated by coronary artery disease (CAD). The performance of ML algorithms across different predictive models was compared using the area under the receiver operating characteristic curve (AUC). In the validation cohort, the XGBoost algorithm within the combined model achieved an AUC value of 0.908, outperforming the best algorithm in the traditional model (AUC = 0.834) and radiomics model (AUC = 0.840). Meanwhile, the Shapley algorithm highlights the additional incremental value of radiomic features. Our model enhances the predictive ability and provides clinicians with a comprehensive tool, facilitating early intervention for high-risk individuals and proactive secondary prevention strategies, which may potentially improve clinical outcomes.

关键词： color stability   surface roughness   CAD/CAM restorative materials   resin nanoceramic   hybrid ceramic   coffee staining  

摘要： The long-term esthetic performance of indirect restorations is closely related to the color stability and surface integrity of the restorative materials used. With the increasing use of CAD/CAM technologies, a wide range of ceramic- and resin-based materials have been developed for indirect restorative applications. These include feldspathic ceramics (VITA Mark II, VITA Zahnfabrik), hybrid ceramics (VITA Enamic, VITA Zahnfabrik), resin nanoceramic CAD/CAM blocks (Lava Ultimate, 3M), and indirect microhybrid resin composites (GC Posterior, GC Corporation). However, these materials are continuously exposed to chemical and mechanical challenges in the oral environment, such as staining from beverages and daily toothbrushing, which may compromise their optical and surface properties over time. The purpose of this in vitro study was to evaluate and compare the color change (Delta E) and surface roughness (Ra) of these materials after repeated coffee immersion and simulated toothbrushing. A total of 240 disk-shaped specimens were fabricated and subjected to three aging cycles consisting of storage in coffee or distilled water, followed by simulated toothbrushing with or without toothpaste. The color parameters were measured using a spectrophotometer according to the CIE Lab* system, surface roughness was assessed using a contact profilometer, and surface topography was qualitatively analyzed by atomic force microscopy. The results demonstrated that coffee immersion significantly increased both color change and surface roughness for all tested materials, with more pronounced effects observed in resin-based materials. Ceramic-based CAD/CAM materials (VITA Mark II and VITA Enamic) showed greater resistance to discoloration and surface degradation, whereas the resin nanoceramic material (Lava Ultimate) and the microhybrid resin composite (GC Posterior) exhibited clinically perceptible color changes and higher roughness values, particularly after toothbrushing with toothpaste.

关键词： Alternative medicine   CAM   Debunking intervention   Health misinformation   Empathetic-refutational interview  

摘要： Debunking interventions to tackle misconceptions related to scientific issues have gained momentum, especially in the context of health care. In this randomized controlled experiment, we assessed the effectiveness of tailored (i.e., contrarian information addressing participants' specific motives with an affirmation of their psychological profile) and non-tailored (i.e., general contrarian information regardless of participants' psychological profile) debunking interventions in a sample of 167 Peruvian participants with positive attitudes toward egg cleanse, a popular local alternative medicine treatment. Our debunking interventions did not significantly correct attitudinal variables related to egg cleanse, such as belief in effectiveness, future use, and preference over conventional medicine. However, exploratory analyses showed significant reductions in endorsement of usage reasons within both the tailored debunk (d = 0.50) and non-tailored debunk (d = 0.62) groups. Moreover, a comparison between the two debunking groups indicated that participants who received a tailored debunk were more satisfied with the interaction with the physician than those who received a non-tailored debunk (d = 0.73). These results suggest that debunking interventions on misinformed health beliefs could have an impact also in the Peruvian cultural context and for alternative medicine, even though more direct attitudinal variables are particularly resistant to change. Strengths and weaknesses of tailored and non-tailored approaches to health misinformation, as well as future research pathways to shed light on the impact and pitfalls of debunking interventions, are discussed.

关键词： Herbal medicine   peptic ulcer   Complementary medicine   Probiotics   Liquorice   Pharmacognosy  

摘要： Peptic ulcer disease (PUD) is still a global health problem, and Helicobacter pylori infection is identified as the principal causative factor. While these are effective, the conventional pharmacological treatments are usually accompanied by side effects, the development of antibiotic resistance, and limited access in some cases. As a result, Complementary and Alternative Medicine (CAM) has become a promising complementary or alternative intervention for PUD. The objective of this systematic review was to assess the therapeutic value, safety, and constraints of CAM interventions for peptic ulcer disease. An extensive systematic review was performed using the PICO format and reported following guidelines, including Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Literature searches were conducted in multiple databases, including the Cochrane Library, Embase, MEDLINE, and the Complementary Medicine Database and included papers from 2000 to 2024. Herbal treatment, complementary medicine, and alternative medicine were the search terms. Available full-text studies had a focus primarily on CAM interventions for PUD. Data were tabulated and synthesized to summarize therapeutic mechanisms, safety profiles, and limitations of the studies. A total of 134 studies met the inclusion criteria, including randomized controlled trials (n approximate to 45), observational studies (n approximate to 30), systematic reviews and meta-analyses (n approximate to 20), and preclinical experimental studies (n approximate to 39). Herbal medicine was studied the most in CAM. There were agents such as Nigella sativa, licorice, turmeric, Aloe vera, and ginger, with gastroprotective, Antioxidant, and anti-H. Pylori effects. Probiotics and acupuncture were supportive, too. Compared to conventional therapies, CAM therapy caused fewer adverse effects. Some drawbacks included heterogeneity in herbal preparations, no standardized dosing, small patient populations, and limit

关键词： B-spline hyperpatch   human knee joint   heterogeneous material modelling   isotropic mesh modelling   reverse engineering  

摘要： Current knee joint reconstruction and visualization are done with the help of CAD modelling software. In this present article, the hyperpatch-based heterogeneous CAD modelling approach has been used to study the knee joint. The peculiarity of this proposed approach is that while constructing the unevaluated model, the B-spline tensor product-based methodology within the control-point-based framework is employed for the heterogeneous CAD model creation. The modelling methodology utilizes the coding and data-extraction tools for reverse engineering and obtaining the necessary data set for reconstructing the heterogeneous material model. Along with the heterogeneous hyperpatch CAD model of the knee joint, the mesh models are generated by utilizing the curves forming the hyperpatch. The obtained mesh models can be used for finite element analysis purposes. The relationship between the number of nodes and material properties was also investigated.

关键词： Drive mechanism   Pressure plate   Flat die-cutting press   Deformation   Hardness   Cam   Law of periodic motion  

摘要： A diagram is proposed, and the principle of operation of the drive mechanism of the pressure plate of a flat die-cutting press is described. The deformations and the required hardness of the working contact surfaces of the executive elements (cams and rollers) of the structure are analytically investigated. The coefficients, which relate the required hardness of the working contact surfaces of parts and material strength, are calculated. Six laws of periodic motion of the corresponding executive link are used in the research, in particular, the smallest values of deformations (triangle = 6.13x10-6 m) and hardness (HB = 1582.1 MPa) of the cams and rollers are established according to the law of periodic motion "Sinusoidal acceleration (symmetrical tachogram)".