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Through room-temperature tensile testing, microstructural observation, and comparative analysis of dislocation configurations, this study investigates the deformation and damage behavior of a high-concentration Re/Ru single-crystal alloy. The results show that the alloy possesses excellent mechanical properties at room temperature, with a tensile strength of 875 MPa and a yield strength of 847 MPa. During tensile deformation, plastic strain primarily occurs through dislocation slip within the γ matrix and dislocation shear into the γ′ phase. Dislocations sheared into the γ′ phase exhibit distinct decomposition patterns. Microcracks initiate at γ′/γ interfaces where two slip systems intersect. As tensile loading continues, these microcracks coalesce, leading to increased local stress and unstable crack propagation along the γ/γ′ interfaces, ultimately resulting in fracture. This process constitutes the deformation and damage mechanism of the alloy during room-temperature tensile deformation. These findings suggest that high Re/Ru concentrations fundamentally alter low-temperature deformation pathways, which may improve resistance to brittle fracture during cold start or handling conditions.

The deformation and damage mechanisms of a single crystal nickel-based superalloy containing 6.0%Re/5.0%Ru were studied through creep performance tests at 800 °C/860–880 MPa, microstructure and morphology observation, and dislocation configuration analyzation. It was found that, during the creep process at the intermediate temperature, the γ′ phase does not form a raft-like structure. After a creep fracture, the distortion degree of the cubic γ′ phase becomes greater when the observation region is closer to the fracture. The alloy has a long creep life at 800 °C, and the dislocation slipping or climbing in the γ matrix is the deformation mechanism at the early and middle creep stages. At the later creep stage, the γ′ phase is sheared by dislocations. Because of the low stacking-fault energy of the alloy, the superdislocation shearing into the γ′ phase can decompose on the 111 plane to form a (1/3) partial dislocation and stacking-fault configuration or cross-slip to the 100 plane to form the Kear–Wilsdorf (K-W) lock, which greatly improves the creep resistance of the alloy. At the later creep stage, the primary/secondary slip systems in the alloy are activated alternately, resulting in micro-cracks at the intersection of the two slip systems. As the creep progresses, the initiated cracks spread and propagate in the γ matrix phase along a direction normal to the stress axis and connect with each other until creep fracture occurs. This is the fracture mechanism of the alloy during creep at the medium temperature.

The effect of solution temperature on the carbide evolution and creep properties of DZ125 directional solidification nickel-based alloy is investigated through solution treatment at different temperatures, mechanical property tests, and microstructure observation. The investigations show that after the low-temperature solution treatment, the dendrite/inter-dendrite regions have obvious microstructure inhomogeneity. The γ′ phase in inter-dendrite regions is coarse, while that in dendrite regions is relatively fine, and some of the massive MC-type carbides in the as-cast alloy are transformed into sieve mesh. After the high-temperature solution treatment, the coarse γ′ phase in inter-dendrite regions is eliminated, and the massive MC-type carbides are transformed into granular M 23 C 6 -type carbides to be dispersively distributed at grain boundaries and intragranular regions. The creep properties of alloys being treated in high-temperature solution are substantially improved at temperatures around 800 °C compared to those of the low-temperature solution-treated alloys. At the late creep stage, under low-temperature solid solution treatment, cracks in the alloy preferentially initiate near massive carbides at grain boundaries. Under high-temperature solid solution treatment, cracks in the alloy preferentially initiate at grain boundaries and the granular carbides act as pegs to the cracks, which hinder crack extension.

Attention-deficit/hyperactivity disorder (ADHD) patients exhibit characteristics of impaired working memory (WM) and diminished sensory processing function. This study aimed to identify the neurophysiologic basis underlying the association between visual WM and auditory processing function in children with ADHD. The participants included 86 children with ADHD (aged 6-15 years, mean age 9.66 years, 70 boys, and 16 girls) and 90 typically developing (TD) children (aged 7-16 years, mean age 10.30 years, 66 boys, and 24 girls). Electroencephalograms were recorded from all participants while they performed an auditory discrimination task (oddball task). The visual WM capacity and ADHD symptom severity were measured for all participants. Compared with TD children, children with ADHD presented a poorer visual WM capacity and a smaller mismatch negativity (MMN) amplitude. Notably, the smaller MMN amplitude in children with ADHD predicted a less impaired WM capacity and milder inattention symptom severity. In contrast, the larger MMN amplitude in TD children predicted a better visual WM capacity. Our results suggest an intimate relationship and potential shared mechanism between visual WM and auditory processing function. We liken this shared mechanism to a total cognitive resource limit that varies between groups of children, which could drive correlated individual differences in auditory processing function and visual WM. Our findings provide a neurophysiological correlate for reports of WM deficits in ADHD patients and indicate potential effective markers for clinical intervention.

Early detection of visual impairment is crucial but is frequently missed in young children, who are capable of only limited cooperation with standard vision tests. Although certain features of visually impaired children, such as facial appearance and ocular movements, can assist ophthalmic practice, applying these features to real-world screening remains challenging. Here, we present a mobile health (mHealth) system, the smartphone-based Apollo Infant Sight (AIS), which identifies visually impaired children with any of 16 ophthalmic disorders by recording and analyzing their gazing behaviors and facial features under visual stimuli. Videos from 3,652 children (≤48 months in age; 54.5% boys) were prospectively collected to develop and validate this system. For detecting visual impairment, AIS achieved an area under the receiver operating curve (AUC) of 0.940 in an internal validation set and an AUC of 0.843 in an external validation set collected in multiple ophthalmology clinics across China. In a further test of AIS for at-home implementation by untrained parents or caregivers using their smartphones, the system was able to adapt to different testing conditions and achieved an AUC of 0.859. This mHealth system has the potential to be used by healthcare professionals, parents and caregivers for identifying young children with visual impairment across a wide range of ophthalmic disorders. A smartphone-based system, designed to induce a steady gaze in children using cartoon-like video stimuli, can identify visually impaired children across a wide range of ophthalmic disorders, based on analysis of gazing behaviors and facial features.

As an inorganic functional material, VO 2 thin films are expected to be used for smart windows. However, these films are not conducive to practical applications when the phase transition temperature ( Tc ) of the VO 2 is approximately 68°C, which is greater than room temperature. To decrease Tc , the effect of Zr 4+ doping on the structure and properties of VO 2 films were investigated. The films were prepared using a sol–gel process, spin-coating on quartz glasses, and annealing at 525°C in a tube furnace within a nitrogen atmosphere. The results demonstrate that these films have a highly preferential crystalline orientation on the substrate; however, the primary two x-ray diffraction pattern peaks shift slightly toward the small angle, and when 7 at.% Zr 4+ was doped in the VO 2 film, the deviation angle was 0.16°, and the crystallite size was approximately 98 nm. A large number of grains were found on the surface of the pure VO 2 films, but all the Zr 4+ doped films had a layered structure, and the thickness of the films was approximately 200 nm. The Tc of these films was characterized using differential scanning calorimetry, and the luminous and solar transmittance was characterized using a UV–Vis–NIR spectrophotometer, which demonstrated that the effect of Zr 4+ doping decreased Tc by approximately 1°C per 1 at.% on average, and the Tc of the 7 at.% film was slightly greater than that of the 5 at.% film, the phase transition temperature of which was 61.4°C. The transmittance decreased as the doping concentration increased, and 1 at.% Zr 4+ doping increased the luminous regulation efficiency (Δ T lum ) and solar modulation efficiency (Δ T sol ). The Δ T lum of the pure VO 2 film and the 1 at.% Zr 4+ -doped VO 2 films was 10.9% and 11.2%, and Δ T sol was 14.4 and 15.2%, respectively.

Background Coronary artery disease (CAD) is one of the most common types of the cardiovascular disease. Previous pilot trials have suggested that Traditional Chinese Medicine (TCM) has brought clinical benefits for patients with CAD. We will conduct this trial to determine the efficacy and safety of Shenzhu Guanxin Recipe Granules (SGR) for the treatment of patients with CAD. Methods This randomized controlled trial recruited 190 patients who were diagnosed with CAD by clinical manifestation and examination and in which coronary computed tomography angiography (CCTA) showed 50–70% stenosis, with soft or mixed plaque types. The included participants were randomly assigned to the case group and control group using a 1:1 allocation ratio; patients in the case group received SGR and usual care, and those in the control group received placebo (6 g/day for 6 months) and usual care. The endpoint of the study included Calcium Coverage Score (CCS), C-reactive protein (CRP) level, and the levels of blood lipids, tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), and ATP-binding membrane cassette transporter A1 (ABCA1) were calculated before recruiting and at the sixth month. The indicators were Seattle Angina Questionnaire (SAQ) and TCM Syndrome Questionnaire scores at 0, 3, and 6 months. Discussion This clinical trial may provide reliable evidence regarding the clinical effectiveness and safety of SGR therapy for patients with CAD diagnosed by clinical manifestation and examination, in which CCTA showed 50–70% stenosis, with soft or mixed plaque types. Trial registration ClinicalTrials.gov, ID: ChiCTR1900020501 . The trial was registered on 25 December 2018.

ObjectiveTo explore the influence of the core symptoms of attention deficit hyperactivity disorder (ADHD) on behavioral problems of children with ADHD propensity, so as to provide references for early identification and targeted intervention for children with ADHD propensity. MethodsFrom July to August 2021, 25 children with ADHD propensity were screened as the ADHD propensity group, and 25 children matched for age, gender and grade were included as the normal group in an elementary school in Guangzhou. ADHD core symptoms were assessed by the Chinese version of the Swanson Nolan and Pelham, version IV-parent form for ADHD (SNAP-IV), and behavioral problems were assessed by Questionnaire-Children with Difficulties (QCD) and Conners Parental Symptom Questionnaire (PSQ). Spearman correlation analysis was used to examine the correlation between ADHD core symptoms and QCD and PSQ scores, and hierarchical linear regression analysis was used to explore the effect of ADHD core symptoms on behavioral problems. Results

Background Coronary artery disease (CAD) is one of the most common types of the cardiovascular diseases, previous pilot trials suggested that Traditional Chinese Medicine brought clinical benefits for patients with CAD. We will conduct this trial to determine the efficacy and safety of Shenzhu Guanxin Recipe Granules for treatment of patients with coronary artery disease. Patients and Methods This randomized controlled trial recruited 194 patients who were diagnosed CAD by clinical manifestations and examinations, in which coronary computed tomography angiography (CCTA) showed 50-70% of stenosis, with soft or mixed plaque. The included participants were randomly assigned to the case group and control group with a 1:1 allocation ratio; patients in the case group received SGR and usual care, and those in the control group received placebo (6 g/day for 6 months) and usual care. The endpoint of the study included calcium coverage score (CCS), C-Reactive protein (CRP), and the levels of blood lipids, tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), and ATP-binding membrane cassette transporter A1 (ABCA1) were calculated before recruiting at6th month. The indicators were Seattle Angina Questionnaire (SAQ) and TCM syndrome questionnaire scores at 0th, 3rd, and 6th months. Discussion This clinical trial may provide a reliable evidence regarding the clinical effectiveness and safety of SGR therapy for patients with CAD by clinical manifestations and examinations, in which coronary computed tomography angiography (CCTA) showed 50-70% of stenosis, with soft or mixed plaque.

R749; 目的 探讨注意缺陷多动障碍(ADHD)核心症状对ADHD倾向儿童行为问题的影响,为早期识别ADHD患儿并进行有针对性的干预提供参考.方法 于2021年7月-8月,在广州市某小学筛选25名ADHD倾向儿童作为ADHD倾向组,纳入年龄、性别和年级相匹配的25名儿童作为正常组.采用中文版ADHD斯诺佩评估量表第4版(SNAP-IV)父母版评定ADHD核心症状,采用儿童困难问卷(QCD)和Conners父母症状问卷(PSQ)评定行为问题.采用Spearman相关分析考察ADHD核心症状与QCD和PSQ评分的相关性,采用分层线性回归分析探讨ADHD核心症状对行为问题的影响.结果 ①组间差异显示,ADHD倾向组的注意缺陷和多动-冲动因子评分均高于正常组(t=7.771、6.726,P均<0.01).②相关分析显示,注意缺陷因子评分与QCD总评分呈负相关(r=-0.440,P<0.05),与PSQ的学习问题因子评分呈正相关(r=0.457,P<0.05);多动-冲动因子评分与PSQ的焦虑因子评分呈负相关(r=-0.457,P<0.05),与PSQ的冲动-多动因子评分呈正相关(r=0.552,P<0.01).③分层线性回归分析显示,注意缺陷因子评分可负向预测QCD总评分(B=-0.682,P<0.05,R2=0.468);多动-冲动因子评分对PSQ的焦虑因子评分具有负向预测作用(B=-0.048,P<0.05,R2=0.367),对PSQ的冲动-多动因子评分具有正向预测作用(B=0.077,P<0.01,R2=0.424).结论 ADHD倾向儿童存在明显的注意缺陷症状、多动-冲动症状及行为问题,且注意缺陷症状可能是其日常行为问题的主要原因,多动-冲动症状可能是其冲动-多动行为问题的主要原因.