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This article explores the significance of friction in mechanics textbooks and the various techniques used to measure coefficients of friction. It specifically focuses on the tilting-plane method, which is commonly employed in classroom teaching to measure the static friction coefficient. Additionally, the article introduces an enhanced version of the tilting-plane method that can measure static friction, kinetic friction, and rolling resistance coefficients in a single test. The setup for this method is simple to construct and suitable for classroom experiments. The article provides comprehensive instructions on how to set up and conduct this method. Furthermore, the text discusses a method for measuring friction coefficients between different surfaces using an experiment involving a metal coin and an inclined plane. By measuring the coin's acceleration as it rolls down the plane at various angles and analyzing the data through graphing, the coefficients of static friction (µs), kinetic friction (µk), and rolling resistance (CR) can be determined. This method can be applied to other objects like spheres, cylinders, or rings, and can aid students in comprehending the characteristics of friction and how to measure friction coefficients. [Extracted from the article]

Cerebral arteries are usually tortuous, and in the treatment of cerebrovascular diseases with stenting, a stent deployed may be collapsed at one end, leading to reduced blood flow and subsequent stent occlusion. Immediate rescuing measures should be implemented to prevent severe ischemic events. In this case report, we present a case with V4 segment occlusion of the right vertebral artery treated with endovascular stent angioplasty. An Enterprise stent deployed at the occlusion segment was collapsed at the proximal end after withdrawal of the delivery system. Immediate rescuing measures were taken by navigating a micro-guidewire through the lateral stent mesh at the proximal end into the stent lumen followed by advancing a second micro-guidewire right through the reopened proximal stent end into the stent lumen for deployment of a supporting balloon-expandable Apollo stent to prevent stent collapse. Follow-up digital subtraction angiography 6 months later demonstrated patent stents and unobstructed blood flow.

Magnetic resonance imaging (MRI) is instrumental in the noninvasive evaluation of tumor tissues in patients subjected to chemotherapy, thereby yielding essential diagnostic data crucial for the prognosis of tumors and the formulation of therapeutic strategies. Currently, commercially available MRI contrast agents (CAs) predominantly consist of mononuclear gadolinium-(III) complexes. Because there is only one Gd-(III) atom per molecule, these CAs often require administration in high doses to achieve the desired contrast quality, which inevitably leads to some adverse events. Herein, we develop a six-nuclei, apoptosis-targeting T1 CA, Gd6–ZnDPA nanoprobe, which consists of a hexanuclear gadolinium nanocluster (Gd6) with an apoptosis-targeting group (ZnDPA). The amplification of Gd-(III) by the hexanuclear structure generates its high longitudinal relaxivity (44.67 mM–1 s–1, 1T) and low r1/r2 ratio (0.68, 1T). Based on the Solomon–Bloembergen–Morgan (SBM) theory, this notable improvement is primarily ascribed to a long correlation tumbling time (τR). More importantly, the Gd6–ZnDPA nanoprobe shows excellent tumor apoptosis properties with an enhanced MR signal ratio (∼74%) and a long MRI imaging acquisition time window (∼48 h) in 4T1 tumor-bearing mice. This study introduces an experimental gadolinium-based CA for the potential imaging of tumor apoptosis in the context of MRI. [ABSTRACT FROM AUTHOR]

There is growing evidence that the defining characteristics of autism spectrum disorder are distributed across the general population; therefore, understanding the correlates of prosocial behavior in individuals with high levels of autistic traits could shed light on autism spectrum disorder and prosocial behavior. In this study, the mechanism underlying the influence of individuals' autistic traits on their prosocial behavior was explored by conducting a questionnaire survey of 414 Chinese college students. The results showed that autistic traits can influence individuals' prosocial behavior not only through the separate effects of received social support and perceived social support but also through the chain mediating effects of received social support and perceived social support; however, the direct effect of autistic traits on individuals' prosocial behavior is not significant. This study is conducive to understanding the internal mechanism underlying the relationship between autistic traits and prosocial behavior. Future work is required to further investigate the clinical autism spectrum disorder samples and cross-cultural applicability of the model found in this study. Autistic traits are known to be associated with a set of core symptoms of autism spectrum disorder. The impact of autistic traits on prosocial behavior, including a consideration of the role of social support, has never been explored. We investigated whether and how social support mediates the autistic trait–prosocial behavior relationship. We found that autistic traits can influence prosocial behavior not only through received social support and perceived social support but also indirectly through the chain mediating effects of received social support and perceived social support. This study contributes to the understanding of how and to what extent prosocial behavior is influenced by autistic traits. Future work is required to further investigate the clinical autism spectrum disorder samples and cross-cultural applicability of the model found in this study. [ABSTRACT FROM AUTHOR]

The evolution of MC-type primary carbonitrides (M=V, Ti, Mo; C=C, N) in terms of morphology, quantity, size and composition was systematically investigated in commercial H13 die steels with different Ti and N contents during thermal holding at 1250 °C for 5 h to 15 h. Results showed that the mean size and quantity of carbonitrides in the four samples had decreased during thermal holding. However, the mean size and quantity of MC carbonitrides had increased with increasing Ti contents when held at 1250 °C while the addition of N increased the quantity but decreased the sizes of the stable MC carbonitrides. It was concluded that the compact carbonitrides could be decomposed and changed into a fishnet structure when held at 1250 °C, especially in samples #1 and #2 containing lower Ti and N contents. The decomposition mechanism was illustrated considering the changes in Ti and Fe elements in carbonitrides. On the basis of the thermodynamic model, the thermal stability of (Tix,V1−x)(Cy,N1−y), with a larger x value, in samples #3 and #4 containing more Ti and N contents was generally higher than those in samples #1 and #2. To control the Ti-containing MC carbonitrides, the low Ti and N contents and high holding temperature should be taken into consideration. [ABSTRACT FROM AUTHOR]

Background: To investigate the effect of the A Direct Aspiration First-Pass Thrombectomy (ADAPT) vs. Solumbra technique in the treatment of acute intracranial atherosclerosis-related large vessel occlusion (LVO).Methods: Patients with acute atherosclerosis-related LVO who had undergone endovascular treatment were retrospectively enrolled into two groups: The Solumbra and ADAPT groups. The clinical data were analyzed.Results: Patients (104) were enrolled with 48 in the Solumbra and 56 in the ADAPT group. The mean time from femoral access to recanalization was significantly (P < 0.05) shorter in the ADAPT than in the Solumbra group. The recanalization time at the first line was significantly shorter in the ADAPT group than in the Solumbra group (17 ± 10.21 vs. 26 ± 15.55 min, P = 0.02). However, the rate of switching to the alternative was significantly higher in the ADAPT group than that in the Solumbra group (46.42 vs. 33.33%, P = 0.01). Eighty-two patients had eventual recanalization, resulting in a final recanalization rate of 78.85%. At 3-month clinical follow-up for all patients, the good prognosis rate reached 51.92% with good prognosis in 24 patients (50%) in the Solumbra and 30 (53.57%) in the ADAPT group. The rate of symptomatic intracranial hemorrhage was 18.75% (n = 9) in the Solumbra and 19.64% (n = 11) in the ADAPT group. The mortality rate was 21.15% (22/104). Among 80 (76.92%) patients who had angiographic follow-up (3–30 months), five (6.25%) patients experienced in-stent stenosis, and two (2.5%) experienced asymptomatic stent occlusion.Conclusion: In patients with acute intracranial atherosclerosis-related LVO, clinical outcomes treated using the ADAPT technique are comparable with those using the Solumbra technique, and more patients need additional remedial measures if treated with the ADAPT technique.

Clinically, social interaction, including gaze-triggered attention, has been reported to be impaired in autism spectrum disorder (ASD), but psychological studies have generally shown intact gaze-triggered attention in ASD. These studies typically examined gaze-triggered attention under simple environmental conditions. In real life, however, the environment is complex. Previous studies have shown that an enhanced cueing effect was found when using eye gaze compared with arrow cues in unpredictably complex conditions in typically developing (TD) individuals. However, in the current study, compared with TD individuals, the cueing effect failed to enhance when using eye gaze compared with arrow cues under complex conditions in individuals with ASD. This may reflect the atypical style of gaze-triggered attention when individuals with ASD adapt to environmental complexity.

The aim of this study was to identify specific cognitive abilities that predict functional outcome in high-functioning adults with autism spectrum disorder (ASD), and to clarify the contribution of those abilities and their relationships. In total, 41 adults with ASD performed cognitive tasks in a broad range of neuro- and social cognitive domains, and information concerning functional outcomes was obtained. Regression analyses revealed that emotion perception and verbal generativity predicted adaptive functioning directly, and the former mediated between the other two. These findings provide the first evidence of a triadic relationship among neuro- and social cognition and functional outcome in this population. Our results suggest that psychosocial interventions targeting these cognitive abilities could benefit social adaptation in adults with ASD.