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关键词： 机织物   梯形试样   撕破强力   不稳定性  

摘要： 为了探究梯形试样的等腰梯形底边长对撕破强力测试结果造成的不稳定性,依据GB/T 3917.3—2009《纺织品织物撕破性能第3部分:梯形试样撕破强力的测定》,试样的等腰梯形底边长分别为104、100、96 mm,对4种不同机织面料进行了测试。结果表明,梯形试样底边长为104 mm时的撕破强力小于底边长为100 mm时的撕破强力,也小于底边长为96 mm时的撕破强力。当底边长偏大时,夹持角度越大,撕破强力结果偏小;底边长偏小,夹持角度越小,撕破强力结果偏大。

关键词： 丝麻面料   透气   凉爽   织物组织   模糊综合评判  

摘要： 为了开发出在炎热条件下穿着舒适、透气性能好、触感凉爽的高端服用面料,采用桑蚕丝作为经纱,大麻(汉麻)纱作为纬纱,在相同的经密下,通过改变织物组织、纬密及经纬组织点等方法,设计并试织了A、B、C三个系列共24种织物,利用织物透气量仪和Hot Disk热常数分析仪分别测试织物的透气和导热系数,并通过模糊综合分析法对各项数据指标进行分析。结果表明:在经密为50根/(10 cm)、纬密为30根/(10 cm)、组织为8枚纬缎时,丝麻面料的透气性、凉爽性能最好;在经密不变、纬密增加时,丝麻面料的透气性、凉爽性下降;随着缎纹经组织点的个数的增加,丝麻面料的透气性、凉爽性会下降;当纬密增加且组织为平纹和斜纹时,丝麻面料的透气性、凉爽性会增加。研究结果可为进一步开发具有透气性、凉爽性高端功能服用面料提供一定的理论参考。

关键词： unsupervised constraints   weakly supervised learning   medical image segmentation   CAM  

摘要： Precise segmentation for skin cancer lesions at different stages is conducive to early detection and further treatment. Considering the huge cost of obtaining pixel-perfect annotations for this task, segmentation using less expensive image-level labels has become a research direction. Most image-level label weakly supervised segmentation uses class activation mapping (CAM) methods. A common consequence of this method is incomplete foreground segmentation, insufficient segmentation, or false negatives. At the same time, when performing weakly supervised segmentation of skin cancer lesions, ulcers, redness, and swelling may appear near the segmented areas of individual disease categories. This co-occurrence problem affects the model's accuracy in segmenting class-related tissue boundaries to a certain extent. The above two issues are determined by the loosely constrained nature of image-level labels that penalize the entire image space. Therefore, providing pixel-level constraints for weak supervision of image-level labels is the key to improving performance. To solve the above problems, this paper proposes a joint unsupervised constraint-assisted weakly supervised segmentation model (UCA-WSS). The weakly supervised part of the model adopts a dual-branch adversarial erasure mechanism to generate higher-quality CAM. The unsupervised part uses contrastive learning and clustering algorithms to generate foreground labels and fine boundary labels to assist segmentation and solve common co-occurrence problems in weakly supervised skin cancer lesion segmentation through unsupervised constraints. The model proposed in the article is evaluated comparatively with other related models on some public dermatology data sets. Experimental results show that our model performs better on the skin cancer segmentation task than other weakly supervised segmentation models, showing the potential of combining unsupervised constraint methods on weakly supervised segmentation.

关键词： AD   Alzheimer Disease   ASL   arterial spin labelling   BAT   Brown adipose tissue   BOLD   blood-oxygen-level-dependent   CMRO2   cerebral metabolic rate of O2 consumption   CAD   coronary artery disease   CBF   cerebral blood flow   CVD   cerebrovascular disorders   DBS   deep brain stimulation   DVT   deep vein thrombosis   fMRI   functional MRI   FOV   field-of-view   HD   Huntington's disease   IDIF   image derived input function   LAF   laminar flow   LAFOV   long axial field of view   LGE   Late Gadolinium Enhancement   MBF   myocardial blood flow   MCI   mild cognitive impairment   MDD   Major Depressive Disorder   MDR   Medical Device Regulations   OEF   oxygen extraction fraction   PAD   peripheral arterial disease   PD   Parkinson's disease   PET   positron emission tomography   PET-MRI   positron emission tomography-magnetic resonance image   PTF   perfusable tissue fraction   PTI   perfusable tissue index   PTSD   post-traumatic stress disorder   PVD   peripheral vascular disease   SPECT   single photon emission computed tomography   TBF   tumor blood flow  

摘要： Imaging water pathways in the human body provides an excellent way of measuring accurately the blood flow directed to different organs. This makes it a powerful diagnostic tool for a wide range of diseases that are related to perfusion and oxygenation. Although water PET has a long history, its true potential has not made it into regular clinical practice. The article highlights the potential of water PET in molecular imaging and suggests its prospective role in becoming an essential tool for the 21st century precision medicine in different domains ranging from preclinical to clinical research and practice. The recent technical advances in high-sensitivity PET imaging can play a key accelerating role in empowering this technique, though there are still several challenges to overcome.

关键词： 禁用偶氮染料   纺织品   气质色谱法   高效液相色谱法   快速检测法  

摘要： 本文主要介绍了偶氮染料的应用现状,阐述了禁用偶氮染料的危害以及国内外对禁用偶氮染料相关标准规定,结合禁用偶氮染料的检测机理,对目前禁用偶氮染料检测方法的研究应用进行了综述,以期为实现更加快速、有效、准确地检测禁用偶氮染料提供指导。

关键词： Computer-aided design   Computer-aided manufacturing   Orthodontic retainers   Retention   Fixed lingual retainer   Treatment stability  

摘要： Bardideh E, Ghorbani M, Shafaee H, Saeedi P, Younessian F. A comparison of CAD/CAM- based fixed retainers versus conventional fixed retainers in orthodontic patients: a systematic review and network meta-analysis. Eur J Orthod. 2023 Sep 18;45(5):545-557. doi:10.1093/ejo/cjad033. PMID: 37471113.

摘要： Custom healing abutments are important in establishing optimal esthetics for prosthesis-driven, implant-supported restorations. This report demonstrates a technique for constructing a custom healing abutment with computer-aided design and computer-aided manufacturing to save chairside time and provide predictable results.

关键词： CAD/CAM block   Shear bond strength   Sonic activated bulk-fill composite   Thermo-viscous bulk-fill composite   Tribochemical silica-coating  

摘要： Background/purpose: To evaluate the shear bond strength (SBS) of nanoceramic hybrid CAD/CAM blocks with two bulk-fill composites in deep margin elevation following different surface pretreatments. Materials and methods: Forty cylindrical-shaped samples (3 mm diameter × 4 mm height) were prepared from each group of bulk-fill resin composites (BRC) (SonicFill 3/SF, VisCalor bulk/VS), and 80 samples (14.5 mm × 7.2 mm × 2 mm) were sectioned from Grandio Block. Specimens of each BRC were assigned to two subgroups, and surfaces of one group were treated with a tribochemical silica-coating. The CAD/CAM block sample surfaces were treated with Al₂O₃ particles. CAD/CAM block and composite samples were luted using dual-cure universal resin-based cement (Bifix QM). Following immersion in distilled water for 24 h, the samples were divided as immediate and test groups. The test group was subjected to thermocycle (5–55 °C, 10,000 cycles). The SBS of the resin-based cement between the blocks and BRC was tested on a universal testing device until failure. Failure type was determined using a stereomicroscope. The roughening pattern was evaluated with SEM. Statistical analysis included Shapiro Wilk, Generalized Linear Models, and Fisher's Exact tests (P < 0.05). Results: No statistically significant difference was found between the mean SBS values according to deep margin elevation materials and surface pretreatment (P > 0.05). Aging procedure resulted in a statistically significant difference between the mean SBS values (P < 0.001). While the mean SBS value was 33.7 ± 7.9 MPa in immediate group, it was calculated as 22.6 ± 6.3 MPa in test group following thermocycle. Conclusion: In terms of SBS, both bulk-fill resin composites performed similarly. Although higher SBS values were obtained with tribochemical silica-coating, the adverse effects of thermocycling on bonding could not be prevented. © 2024 Elsevier Ltd

关键词： CABG, Veterans, VASQIP, 30-day mortality, Homelessness   Racial disparities   AS   Aortic stenosis   ASA   American Society of Anesthesiologists   CAD   Coronary artery disease   CABG   Coronary artery bypass grafting   COPD   Chronic obstructive pulmonary disease   CPR   Cardiopulmonary resuscitation   DM   Diabetes mellitus   IABP   Intra-aortic balloon pump   IQR   Interquartile range   LV   Left ventricle   LAD   Left anterior descending   LMC   Left main coronary   MI   Myocardial infarction   MR   Mitral regurgitation   NYHA   New York Heart Association   US   United States   VASQIP   Veterans Affairs Surgical Quality Improvement Program  

摘要： Coronary artery disease requiring surgical revascularization is prevalent in United States Veterans. We aimed to investigate preoperative predictors of 30-day mortality following coronary artery bypass grafting (CABG) in the Veteran population. The Veterans Affairs Surgical Quality Improvement (VASQIP) national database was queried for isolated CABG cases between 2008 and 2018. The primary outcome was 30-day mortality. A multivariable logistic regression was performed to assess for independent predictors of the primary outcome. A P-value of <0.05 was considered statistically significant. A total of 32,711 patients were included. The 30-day mortality rate was 1.37%. Multivariable analysis identified the following predictors of 30-day mortality: African-American race (OR 1.46, 95% CI 1.09-1.96)