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关键词： Contrastive learning   Developmental dysplasia of the hip   Dual-domain masked image modeling   Frequency domain   Self-supervised learning   Spatial domain  

摘要： Existing B-mode ultrasound (BUS) based computer-aided diagnosis (CAD) for developmental dysplasia of the hip (DDH) is mainly developed based on the Graf's method by segmenting crucial anatomical structures. However, their diagnosis performance heavily depends on the accuracy of segmentation algorithms. To this end, the pioneering CAD models based on non-Graf's method have shown their feasibility and effectiveness for DDH diagnosis. However, the deep neural network based models generally suffer from the issue of small sample size. In this work, a novel hybrid multi-task self-supervised learning algorithm, named Dual-Domain Masked Image Modeling (MIM) based Contrastive Learning (DDMCL), is proposed to improve the diagnosis performance of CAD model for DDH with limited BUS training samples. The DDMCL performs both the spatial domain MIM and frequency domain MIM to learn more comprehensively intrinsic representations from BUS images, and then integrates the dual-domain features into the contrastive learning (CL) framework. Moreover, a new hybrid loss function, i.e. the energy and mutual information based loss (named EM-Loss), is developed to jointly optimize the dual-domain network branches in CL, which can effectively distinguish the dual-domain features with large discrepancy. The experimental results on two DDH BUS datasets indicate that the proposed DDMCL outperforms all the compared algorithms, suggesting its effectiveness. © 2024 Elsevier Ltd

关键词： 多道焊接热循环   铝合金接头   热影响区   力学性能   析出相演变  

摘要： 采用ER5087铝合金焊丝在6082-T6铝合金板上进行四道双脉冲熔化极惰性气体保护堆焊,在焊接热影响区不同位置取样进行显微组织观察和力学性能测试,结合焊接温度场数值模拟研究了多道焊接热循环对热影响区不同位置显微组织及力学性能的影响。结果表明:根据试验测得的热影响区截面硬度变化和模拟得到的热影响区截面峰值温度变化规律,结合材料热处理工艺将6082-T6铝合金焊接接头热影响区按照距熔合线由远到近分为过时效区(A区)、严重过时效区(B区)和固溶区(C区)。随着焊接道次的增加,热影响区晶粒粗化,A区析出相发生β″相+β'相→β'相+U2相→β相+β'相+半溶解相→β'相+半溶解相转变;不同道次焊接后B区析出相基本呈半溶解状态,C区有序析出相完全溶解,析出大量GP区;随着焊接道次的增加,热影响区A区、B区的析出相逐渐粗化和溶解,C区的GP区数量减少。四道焊接后,热影响区整体力学性能下降,热影响区B区的软化现象最严重。热影响区软化的主要原因是析出相的演变而非晶粒的粗化。

关键词： 病理性近视   脉络膜新生血管   微循环   血流密度   光学相干断层扫描血管成像  

摘要： 目的:应用光学相干断层扫描血管成像(OCTA)定量分析病理性近视(PM)继发脉络膜新生血管(mCNV)患者黄斑区组织结构及微循环的变化。方法:病例对照研究。随机纳入2020年5月至2021年2月于扬州大学附属苏北人民医院眼科确诊为PM的患者57例(60眼),其中PM合并脉络膜新生血管(CNV)患者30例(30眼)作为mCNV组,无合并CNV的PM患者27例(30眼)作为无CNV组,同时选择本院眼科门诊检查后正常且年龄与PM患者匹配的健康人29例(30眼)作为对照组。所有纳入对象均测量等效球镜度(SE)、眼轴长度(AL)、最佳矫正视力(BCVA)。采用OCTA测量黄斑中心凹无血管区(FAZ)面积、周长和血流密度(FVD);黄斑中心凹、旁中心凹及旁中心凹4个分区的全层(FRT)、内层(IRT)和外层视网膜厚度(ORT)及浅层(SVD)和深层视网膜血流密度(DVD);中心凹下脉络膜厚度(SFCT)和脉络膜毛细血管层血流密度(CC-VD)。采用方差分析比较3组间AL、SE、黄斑血流密度、视网膜厚度、FAZ相关指标、脉络膜厚度及血流密度等差异。结果:3组间黄斑中心凹的FRT、IRT、ORT及全层SVD、DVD、FVD、FAZ面积及周长、CC-VD总体差异均有统计学意义(F=3.41~11.14,P<0.05)。进一步组间比较显示,与对照组相比,mCNV组的中心凹FRT、IRT、ORT均明显增加(均P<0.05),全层及旁中心凹的SVD和DVD、颞侧及鼻侧的SVD、鼻侧及下方的DVD、FVD、CC-VD均明显降低(均P<0.05);无CNV组中心凹IRT、中心凹DVD均明显增加(P<0.05),全层和旁中心凹及4个分区的SVD、FVD、FAZ面积及周长均明显降低(均P<0.05);无CNV组和mCNV组的SFCT均明显降低,差异均有统计学意义(均P<0.001)。与无CNV组相比,mCNV组的中心凹FRT、ORT均明显增加(均P<0.001),中心凹DVD、旁中心凹及鼻侧DVD、CC-VD均明显降低(均P<0.05)。结论:mCNV患者黄斑区视网膜增厚、中心凹下脉络膜变薄,其中黄斑中心凹ORT变化最为明显,浅层及深层视网膜、黄斑中心凹、脉络膜毛细血管层的血流密度较正常人群降低。

关键词： TGF-β1   Transforming growth factor beta 1   IHD   Ischemic heart disease   MI   Myocardial Infarction   TC   Total cholesterol   TG   Triglyceride   LDL   Low density lipoprotein   HDL   High density lipoprotein   VLDL   Very low-density lipoprotein   SNP   Single nucleotide polymorphism   HR   Hazard ratio   CI   Confidence interval   CAD   Coronary artery disease   Leu   Leucin   Pro   Proline   ECG   Electrocardiographic   ELISA   Enzyme linked immune sorbent assay   EF   Ejection fraction   HWE   Hardy-Weinberg equilibrium   NCBI   National Center for Biotechnology Information   IS   Ischemic stroke   CI   Cerebral infarction   Immunogenetics   Ischemic heart disease   Genetic polymorphism   Haplotype   TGF-β1  

摘要： Transforming growth factor beta 1 (TGF-β1) is considered a pleotropic cytokine involved in the progression of cardiovascular disease. The purpose of the current study was to identify the relationship between serum levels of TGF-β1, the genetic variations (C509T rs1800469, T869C rs1800470) and their constructed haplotypes with the susceptibility of ischemic heart disease (IHD) in the Iraqi population. The case-control study enrolled 200 participants, including 100 patients with IHD and 100 healthy controls. Genotypes of (TGF-β1) polymorphisms were performed by TaqMan allele-specific probes detected by real-time PCR (RT-PCR). The serum level of TGF-β1 was measured by an ELISA assay. The obtained results showed that the two minor alleles of C509T rs1800469 and T869C rs1800470 were associated with a decreased risk of IHD, preventive fraction (PF%) = 11.6 %; 23.9 %, respectively. Genotype distribution was significantly noted in the TT genotype of C509T rs1800469 (p = 0.033) and in the TC genotype of T869C rs1800470 (p = 0.006) between patients and control groups. A significant distribution was seen in the C allele of T869C rs1800470 (p = 0.002) between the studied groups. The carriers of the TT genotype in the C509T rs1800469 and the TC; CC genotypes in the T869C rs1800470 decreased the chance of having IHD, (hazard ratio HR<1). Furthermore, the haplotype analysis observed that H1 (C-T) was significantly associated with the development of IHD (HR=1.66; 95 % CI=1.10–2.51; p = 0.021) and the inverse effect of H4 (T-C), (HR=0.36; 95 % CI=0.20–0.65; p = 0.001). The TGF-β1 alleles of both SNPs, TT genotype of C509T rs1800469, TC, CC of T869C rs1800470 and H4 locus of haplotypes were suggested to be protective biomarkers against IHD in Iraqi population.

关键词： Temporal Cortex   Bdnf   Rc3   Antioxidant Enzyme   Circadian Rhythm   Aging   AA   Arachidonic acid   ANOVA   Analysis of variance   BMAL1   Brain and Muscle ARNT-Like 1   BDNF   Brain-derived neurotrophic factor   CaM   Calmodulin   CAT   Catalase   CLOCK   Circadian Locomotor Output Kaput   CRY   Cryptochrome   CT   Circadian Time   DD   constant darkness condition   DHA   Docosahexaenoic acid   E-box   Enhancer-Box   FMRP   Fragile X Mental Retardation Protein   GPx   Glutathione Peroxidase   LD   Light-Dark condition   LPO   Lipoperoxidation   LTD   long-term depression   LTM   Long-Term-Memory   LTP   long-term potentiation   MDA   Malondialdehyde   NMDAR   N-methyl D-aspartate Receptor   PER1   Period circadian protein homolog 1   PKC   Protein Kinase C   PUFAs   Polyunsaturated Fatty Acids   Rc3   Neurogranin   RAR   Retinoic Acid Receptor   RORa   Retinoic Acid-related Orphan Receptor a   ROS   Reactive Oxygen Species   SCN   Suprachiasmatic Nucleus   TBARS   Thiobarbituric acid Reactive Substances   TC   Temporal Cortex   Trk-B   Tropomyosin related kinase B  

摘要： Graphical abstract

关键词： 印染助剂   纺织品   化学品   生产过程中   抗皱   甲醛   防护措施   管理和使用  

摘要： 甲醛被广泛应用于印染助剂,在纺织品的生产过程中扮演着重要角色在纺织品的生产过程中,化学品的使用不可或缺。其能赋予纺织品柔软、抗皱、防水等不同的特性,但与此同时也可能对环境安全和人类健康造成隐患。因此,正确地管理和使用这些化学品至关重要。作为负责任的企业,李宁公司致力于向消费者普及化学品知识,以期提高公众对化学品潜在风险的认识,与消费者共同采取有效的防护措施,守护纺织品的安全。

关键词： 水-空交替控时淬火   低合金耐磨钢   组织   性能  

摘要： 针对低合金耐磨钢ZG30CrMnSiMoVTi经淬火-配分(Q-P)处理后组织分布不均匀的问题,采用水-空交替循环控时淬火(ATQ)工艺进行热处理,通过模拟计算分析了不同条件下试验钢的冷却曲线,确定了ATQ处理工艺细节。借助OM、SEM、EDS、洛氏硬度计、冲击试验机和拉伸试验机对不同循环次数下ATQ处理试验钢的微观组织和力学性能进行了研究。结果表明,经过ATQ处理的试验钢中出现了大量的马氏体和少量的贝氏体组织。经过ATQ循环3次的试验钢的组织分布最为均匀,贝氏体含量最多,而且力学性能最优。ATQ循环3次的试验钢的平均洛氏硬度为46.45 HRC,冲击吸收能量为29.1 J,抗拉强度为1551.69 MPa,屈服强度为1293.07 MPa,断后伸长率为12.6%。

关键词： ACE   angiotensin-converting enzyme   AMPK   AMP-activated protein kinase   Ang II   angiotensin II   β-ARs   beta-1 adrenergic receptors   BH4   tetrahydrobiopterin   CaM   calmodulin   EDRF   endothelium-derived relaxing factor   eNOS   endothelial nitric oxide synthase   Fe2   iron in ferrous state   Fe3   iron in ferric state   FDA   Food and Drug Administration   Hb-NO   heme-nitric oxide   iNO   inhaled nitric oxide   iNOS   inducible nitric oxide synthase   IR   ischemia-reperfusion   Km   Michaelis–Menten constant   nNOS   neuronal nitric oxide synthase   NO   nitric oxide   NO2   inorganic nitrite   NO3   inorganic nitrate   NO2-FA   nitro-fatty acid   NOS   nitric oxide synthase   NOX   NADPH oxidase   O2   superoxide   P2Y   purinergic receptor   PDE   phosphodiesterase   PKA   protein kinase A   PKG   protein kinase G   RAAS   renin-angiotensin-aldosterone system   RBC   red blood cell   ROS   reactive oxygen species   sGC   soluble guanylyl cyclase   TSP1   thrombospondin-1   WT   wild-type  

摘要： Nitric oxide (NO) from endothelial NO synthase importantly contributes to vascular homeostasis. Reduced NO production or increased scavenging during disease conditions with oxidative stress contribute to endothelial dysfunction and NO deficiency. In addition to the classical enzymatic NO synthases (NOS) system, NO can also be generated via the nitrate-nitrite-NO pathway. Dietary and pharmacological approaches aimed at increasing NO bioactivity, especially in the cardiovascular system, have been the focus of much research since the discovery of this small gaseous signaling molecule. Despite wide appreciation of the biological role of NOS/NO signaling, questions still remain about the chemical nature of NOS-derived bioactivity. Recent studies show that NO-like bioactivity can be efficiently transduced by mobile NO-ferroheme species, which can transfer between proteins, partition into a hydrophobic phase, and directly activate the soluble guanylyl cyclase-cGMP-protein kinase G pathway without intermediacy of free NO. Moreover, interaction between red blood cells and the endothelium in the regulation of vascular NO homeostasis have gained much attention, especially in conditions with cardiometabolic disease. In this review we discuss both classical and nonclassical pathways for NO generation in the cardiovascular system and how these can be modulated for therapeutic purposes.

摘要： Superclusters, encompassing environments across a wide range of overdensities, can be regarded as unique laboratories for studying galaxy evolution. Although numerous supercluster catalogs have been published, none of them goes beyond redshift z = 0.7. In this work, we adopt a physically motivated supercluster definition, requiring that superclusters should eventually collapse even in the presence of dark energy. Applying a friends-of-friends (FoF) algorithm to the CAMIRA cluster sample constructed using the Subaru Hyper Suprime-Cam survey data, we have conducted the first systematic search for superclusters at z = 0.5-1.0 and identified 673 supercluster candidates over an area of 1027 deg2. The FoF algorithm is calibrated by evolving N-body simulations to the far future to ensure high purity. We found that these high-z superclusters are mainly composed of two to four clusters, suggesting the limit of gravitationally bound structures in the younger Universe. In addition, we studied the properties of the clusters and brightest cluster galaxies (BCGs) residing in different large-scale environments. We found that clusters associated with superclusters are typically richer, but no apparent dependence of the BCG properties on large-scale structures is found. We also compared the abundance of observed superclusters with mock superclusters extracted from halo light cones, finding that photometric redshift uncertainty is a limiting factor in the performance of superclusters detection.

关键词： Anti-Calmodulin antibodies   CALM1   CALM2   CALM3   Ca2+ signaling   CaM   CaM1   CaM2   CaM3   Calmodulin genes  

摘要： Calmodulin (CaM) is a ubiquitous intracellular calcium receptor that regulates a plethora of cellular functions through interactions with target proteins. In mammals, an identical Calmodulin protein is expressed by 3 independent genes (CALM1, CALM2, CALM3). Therefore, antibodies generated against either of the three products (CaM1, CaM2, CaM3) of these genes cannot be distinguished, and conclusions based on the supposedly specific CaM antibodies claiming functions of one of the 3 genes may be misleading. In this paper we present 44 articles, using such antibodies for Western blot, ELISA assay, immunohistochemistry or which are based on proteomics and the use of databases with incorrect annotations, all potentially reaching misleading conclusions. This should be taken as a note of caution for researchers working with Calmodulin antibodies and misleading databases.