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The healthy context paradox is defined as the phenomenon that victims’ psychological adjustment worsens in a context with a lower rate of victimization. The unexpected pattern was primarily confirmed in children and adolescents from western societies, and it is unclear whether classroom-level victimization could moderate the link between peer victimization and psychological adjustment in the Chinese cultural context, where Confucian philosophies and collectivism are highly valued. Furthermore, most existing research used a single method to assess peer victimization. The current study attempted to examine classroom-level peer victimization as a moderator in the association between individual-level peer victimization and depression, self-esteem, and well-being among 2613 Chinese seventh graders (1237 girls, M age = 13.00±.61) from 47 classrooms ( M classroom size = 55.60, range from 45 to 65) using both self-reported and peer-reported information on peer victimization. At the individual level, the results revealed that both self- and peer-reported victimization were positively related to depression and negatively related to self-esteem and well-being. Most importantly, consistent with past findings documenting the healthy context paradox, self-reported victimized youth experienced a higher level of depression and lower level of self-esteem and well-being in classrooms where the overall level of victimization was relatively low. However, the healthy context paradox was not replicated in the nominated data of peer victimization. These results confirmed the healthy context paradox in Chinese culture to some extent. The findings emphasize the importance of measuring peer victimization from multiple sources and suggest there is a need for additional support to victimized middle school students where the classroom context was relatively healthy.

Summary C-Alkyl glycosides occur widely in nature and are indispensable in drug development programs, owing to their diverse range of medicinal properties. Previous synthetic efforts often utilize stoichiometric reagents, and catalytic methods that afford such glycosides exhibit limited scope. Here, we describe a stereoselective Ti-catalyzed regime that efficiently merges a vast array of readily available glycosyl chlorides with activated olefins, through stereocontrolled glycosyl radical addition to deliver an assortment of C-alkyl glycosides. By employing alkynes as radical acceptors, the present strategy is amenable to the synthesis of C-alkenyl glycosides bearing a Z olefin appendage. The unexpected greater reactivity of glycosyl chlorides (compared with simple tertiary chloroalkanes) in the presence of an organotitanium complex is elucidated through mechanistic and computational studies. Utility of the protocol is underscored by the concise preparation of therapeutically important carbohydrates and glycopeptide conjugates, which are difficult to access using alternative approaches.

C-vinyl glycosides are an important class of carbohydrates and pose a unique synthetic challenge. A new strategy has been developed for stereoselective synthesis of C-vinyl glycosides via Pd-catalyzed directed C-H glycosylation of alkenes with glycosyl chloride donors using an easily removable bidentate auxiliary. Both the γ C-H bond of allylamines and the δ C-H bond of homoallyl amine substrates can be glycosylated in high efficiency and with excellent regio- and stereoselectivity. The resulting C-vinyl glycosides can be further converted to a variety of C-alkyl glycosides with high stereospecificity. These reactions offer a broadly applicable method to streamline the synthesis of complex C-vinyl glycosides from easily accessible starting materials.

Despite the significant progress in carbohydrate chemistry, there remains a pressing need for efficient and practical glycosylation methods using simple glycosyl donors and with high atom economy. ...

The C2-α-mannosyl-tryptophan amino acid is produced by a unique posttranslational modification (PTM) of proteins and poses a significant synthetic challenge. A new strategy based on Pd-catalyzed au...

Studies have demonstrated that bullying victimization is a risk factor for depressive symptoms; however, little is known about the underlying processes that may mediate or moderate this relationship. To address this research gap, this study examined the mediating effects of personal and general belief in a just world (BJW) and the moderating effect of classroom-level victimization on the relationship between bullying victimization and depressive symptoms. Using a short-term longitudinal design, two-wave data were obtained from 2,551 Chinese adolescents (initial age = 12.99 ± 0.61, 52.2% boys) from 47 classes over 6 months. The results indicated that Time 1 personal BJW mediated the relationship between Time 1 bullying victimization and Time 2 depressive symptoms. Furthermore, the mediating effect of Time 1 personal BJW was moderated by Time 1 classroom-level victimization; this effect was stronger for adolescents in classrooms with low levels of victimization. These findings contribute to our understanding of how and when bullying victimization impacts youth depressive symptoms. Education practitioners should pay special attention to personal BJW in victimized adolescents, especially when classroom-level victimization is low.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors that threaten human health; thus, the establishment of an animal model with clinical features similar to human hepatocellular carcinoma is of important practical significance.Taking advantage of the novel microcarrier-6, human HCC cells were injected into immunocompetent mice to establish a novel human HCC patient-derived xenograft (PDX) model. Primary HCC cells were isolated from fresh hepatocellular carcinoma tissues, which were subsequently co-cultured with microcarrier-6 to construct a three-dimensional tumor cell culture model in vitro. The HCC-microcarrier complex was implanted into mice by subcutaneous inoculation, and the tumor formation time, tumor formation rate, and pathological manifestation were recorded. Changes of immune parameters in mice were detected by flow cytometry.The success rate was 60% (6/10) in the establishment of hepatocellular carcinoma PDX mouse model, and the total tumor formation rate of the tumor-forming model is 90-100%. HE staining and immunohistochemical experiments indicate that the model well retained the characteristics of the primary tumor. Interestingly, M2 macrophages in tumor-bearing mice increased significantly, and the levels of CD4Through the application of the microcarrier-6 in immunocompetent mice, we successfully established a novel human HCC PDX model, which can be used to better study and further elucidate the occurrence and pathogenic mechanism of HCC, improve the predictability of toxicity and drug sensitivity in HCC.

To explore the clinical and genetic characteristics of five families with primary periodic paralysis (PPP). We reviewed clinical manifestations, laboratory results, electrocardiogram, electromyography, muscle biopsy, and genetic analysis from five families with PPP. Five families with PPP included: hypokalemic periodic paralysis type 1 (HypoPP1, CACNA1S, 1/5), hypokalemic periodic paralysis type 2 (HypoPP2, SCN4A, 2/5), normokalemic periodic paralysis (NormoPP, SCN4A, 1/5), and Andersen-Tawil syndrome (ATS, KCNJ2, 1/5). The basic clinical manifestations of five families were consistent with PPP, presenting with paroxysmal muscle weakness, with or without abnormal serum potassium. ATS was accompanied by ventricular arrhythmias, and skeletal and craniofacial anomalies, developing with a permanent fixed myopathy later. The electromyography showed diffuse myopathic discharge, and muscle biopsy showed tubular aggregates. Genetic testing revealed five families with PPP carried CACNA1S (R1242S), SCN4A (R675Q, T704M), and KCNJ2 (R218Q) respectively. The novel heterozygous R1242S mutation in CACNA1S caused a conformational change in the protein structure, and the amino acid of this mutation site was highly conserved among different species. SCN4A mutations led to two phenotypes of HypoPP2 and NormoPP. PPPs are autosomal dominant disorders of ion channel dysfunction characterized by episodic flaccid muscle weakness secondary to abnormal sarcolemmal excitability. PPPs are caused by mutations in skeletal muscle calcium channel CaV1.1 gene (CACNA1S), sodium channel NaV1.4 gene (SCN4A), and potassium channels Kir2.1, Kir3.4 genes (KCNJ2, KCNJ5), including HypoPP1, HypoPP2, NormoPP, HyperPP, and ATS, which have significant clinical and genetic heterogeneity. Diagnosis is based on the characteristic clinical presentation then confirmed by genetic testing.

Chinese rural-to-urban migrant children frequently experience discrimination, which thereby often results in significant negative consequences. However, little is known about the contribution of perceived discrimination experiences to non-suicidal self-injury (NSSI). This study aimed to examine the relationship between perceived discrimination and NSSI, the mediating role of loneliness in this relationship, and the moderating roles of parent-child cohesion and gender. Six hundred fifty-seven migrant children completed a perceived discrimination scale, an NSSI questionnaire, a loneliness scale, and a parent-child cohesion inventory. Results showed that there was a significant positive association between perceived discrimination and NSSI among migrant children. Loneliness mediated the relationship between perceived discrimination and NSSI. Moreover, parent-child cohesion demonstrated a moderating effect on the mediation via loneliness; the indirect association between perceived discrimination and NSSI via loneliness was only significant in low parent-child cohesion condition, but not in the high condition. Additionally, there were differences by gender, with a significantly stronger mediating effect of loneliness among migrant girls compared with migrant boys. The findings from this study contribute to the understanding of the underlying mechanisms in the relationship between perceived discrimination and NSSI. Discussion also provides directions for future interventions and delineate how programs could be designed to target loneliness and parent-child cohesion among migrant children.

Objective Chinese left-behind children have faced a high level of stress and tend to engage in nonsuicidal self-injury (NSSI) behavior. However, the impacts of parental migration on NSSI are complex. The improved family's socioeconomic status (SES) could have positive impacts on these children's mental health, yet the parental absence could have negative influences. To explore the complex dynamics of parental migration on NSSI, this study examined the roles of parent-child cohesion and SES in the relationship between stressful life events and NSSI. Method A total of 509 left-behind children completed self-report surveys that addressed stressful life events, NSSI, parent-child cohesion, and SES. Results Stressful life events were positively related to NSSI in both the migrant father and two migrant parents' groups. Furthermore, for children with migrant fathers, father-child cohesion and SES significantly moderated the relation between stressful life events and NSSI. The interaction of stressful life events, mother-child cohesion, and SES also was significant. For children with two migrant parents, mother-child cohesion was negatively related to NSSI. No significant interactions were found in this group. Conclusions The findings suggested that, although parent-child cohesion and SES were both important for the prevention of NSSI among left-behind children, parent-child cohesion should remain a priority.

Background: Loneliness is common among left-behind adolescents and can affect their friendship quality both negatively and positively. Most studies have focused on the negative effect of loneliness on friendship. However, loneliness may also motivate adolescents to seek close connections with peers through certain ways, that is, loneliness may indirectly positively influence friendship quality, which has not been explored. To address this gap, based on the life history theory and the interpersonal function model of non-suicidal injury (NSSI), this study aimed to examine the positive impact of loneliness on friendship quality via NSSI among left-behind adolescents. Moreover, given that NSSI is a severe health concern that should be prevented, the protective role of parent-child cohesion was also examined. Methods: A two-wave dataset was used. Participants comprised 1,013 adolescents (539 left-behind and 474 non-left-behind adolescents) completed self-report surveys that addressed loneliness, NSSI, friendship quality, and parent-child cohesion. Results: For left-behind adolescents, loneliness could affect friendship quality not only negatively but also positively through NSSI; increased loneliness predicted more NSSI which, in turn, was associated with high friendship quality. Moreover, the moderating effect of parent-child cohesion was significant. For non-left-behind adolescents, neither the direct nor the indirect positive effect through NSSI between loneliness and friendship quality was found. Limitations: All measures were based on self-reports. Cohesions with caregivers were not included. Conclusions: Findings advance our understanding of the relationships between loneliness, NSSI, and friendship quality among left-behind adolescents. They provide important implications for future interventions by addressing the role of high parent-child cohesion.

Gastric cancer is among the most common malignant tumors of the digestive tract. Establishing a robust and reliable animal model is the foundation for studying the pathogenesis of cancer. The present study established a mouse model of gastric carcinoma by inoculating immunocompetent mice with MKN45 cells using microcarrier. Sixty male C57BL/6 mice were randomly divided into three groups: a 2D group, an empty carrier group, and a 3D group, according to the coculture system of MKN45 and the microcarrier. The mouse models were established by hypodermic injection. Time to develop tumor, rate of tumor formation, and pathological features were observed in each group. In the 3D group, the tumorigenesis time was short, while the rate of tumor formation was high (75%). There was no detectable tumor formation in either the 2D or the empty carrier group. Both H&E and immunohistochemical staining of the tumor xenograft showed characteristic evidence of human gastric neoplasms. The present study successfully established a human gastric carcinoma model in immunocompetent mice, which provides a novel and valuable animal model for the cancer research and development of anticancer drugs.

Although research has indicated the association between child abuse and non-suicidal self-injury (NSSI), few studies have examined their relationship in a particular sample of Chinese rural-to-urban migrant adolescents who tend to experience parental abuse and engage in NSSI. More importantly, factors moderating the relationship between child abuse and migrant adolescents’ NSSI have been understudied. To address this issue, this study aimed to examine whether beliefs about adversity and family socioeconomic status (SES) moderated the longitudinal relationship between child abuse and NSSI in a sample of Chinese migrant adolescents. 308 Chinese rural-to-urban migrant adolescents (aged 10–14; 138 boys) completed the two-wave survey. Self-reported questionnaires regarding child abuse, NSSI, beliefs about adversity, and family SES were used. Results showed that child abuse was significantly positively related to NSSI a year later. Moreover, the interaction of child abuse, beliefs about adversity, and family SES was significant. Specifically, for migrant adolescents with low SES, positive beliefs about adversity played a protective role in the association between child abuse and NSSI; while for those with high SES, such beliefs showed vulnerability. Findings underscore the importance of considering multiple resilient factors simultaneously by examining beliefs about adversity and SES as the moderating mechanisms in the association between child abuse and NSSI. Findings also emphasize the significance of developing differential interventions targeting NSSI in abused Chinese migrant adolescents. Positive beliefs about adversity are important in buffering the negative effect of child abuse for migrant adolescents with low SES. For those with high SES, special attention should be given to the interactive impact of child abuse, beliefs about adversity, and family SES.

With the increase in computing power and the development of reinforcement learning, the efficiency of the transportation system have been improving. Data-driven reinforcement learning algorithms have strong self-learning capabilities and adaptability to complex transportation systems and play a key role in the development of intelligent transportation systems. This paper reviews the basic concept of reinforcement learning firstly, including the terminology and methods which are divided into three categories: value-based, policy-based, and actor-critic methods. Secondly, the application and development of reinforcement learning in traffic signal control are introduced in the single-point control and the joint control of the multi-agent system. Then, this paper describes the development in autonomous driving separately from path planning and driving behavior. In the end, this paper concludes the challenges and problems faced by reinforcement learning methods in intelligent transportation systems.

Parental involvement in adolescents’ learning has been linked to high academic achievement, yet few studies have examined its reverse relationship at the same time and the potential mechanisms that underly these associations. To address this research gap, this study investigated the reciprocal relationship between parental involvement and academic achievement as well as the mediating role of adolescents’ academic engagement among Chinese adolescents. In addition, the current study explored whether these relationships varied by gender. Using a longitudinal design, a total of 2381 secondary school students (48.8% girls, Mage = 13.38 ± 0.59) participated in the study. The results found significant positive directional effects from academic achievement to parental involvement among total sample, but not vice versa. The cross-lagged effect from academic achievement to parental involvement only existed among adolescent girls. Bootstrap analyses in the total sample revealed that parental involvement was related to academic achievement through the indirect effects of adolescents’ behavioral engagement. In terms of gender differences, behavioral engagement totally mediated the path from academic achievement to parental involvement for boys, while no significant mediation effect was found for girls. These results have provided empirical evidence of the evocative role of adolescents’ academic characteristics on parenting behaviors and the double-edged effect of parental involvement on adolescents’ academic performance, they also suggest that further research is needed to explore effective and appropriate ways for parents to get involved in adolescents’ learning in order to promote their children’s academic achievement.

Peer victimization is a serious issue among school-aged children. Chinese left-behind children tend to experience peer victimization and associated nonsuicidal self-injury (NSSI) behavior. However, the possible improvement of subjective socioeconomic status (SES) based on increased family income may serve to buffer the relationship between peer victimization and NSSI, and this buffering effect may differ by level of social support. Thus, the current study aimed to examine the moderating effect of subjective SES on the relationship between peer victimization and NSSI by the level of social support among Chinese left-behind children. A total of 431 left-behind children and 447 non-left-behind children (comparison group) completed self-report scales measuring peer victimization, NSSI, subjective SES, and social support. Results showed that peer victimization was positively related to NSSI among left-behind children, but not among non-left-behind children. Moreover, for left-behind children with low levels of social support, high subjective SES intensified the association between peer victimization and NSSI; peer victimization was positively associated with NSSI among left-behind children who reported high subjective SES, but not among those with low subjective SES. However, high levels of social support seemed to protect the left-behind children with high subjective SES who experienced peer victimization from NSSI. For non-left-behind children with both parents present, high subjective SES played a protective role in the association between peer victimization and NSSI, regardless of the levels of social support they enjoyed. These findings contribute to an understanding of subjective SES as a moderating mechanism in the association between peer victimization and NSSI among left-behind children. Social support proved central to the protective role of subjective SES. Intervention programs to enhance social support can help to strengthen the protective effect of subjective SES on NSSI among left-behind children who experience peer victimization.

Background Left-behind adolescents who are from father-migrant/mother caregiver families have become the main type of left-behind children in China. The migratory of fathers not only makes left-behind adolescents suffer more difficulties but also causes left-behind women to face the challenge of raising the child alone. This study examined the association among peer victimization, maternal psychological control, and adjustment problems among Chinese rural left-behind adolescents. Furthermore, we first explored the moderating role of maternal behavioral control in this relationship. Methods Using cross-sectional design, we recruited 194 left-behind adolescents (49% girls; mean age = 13.51, SD = 1.03) from four junior schools in the Guizhou province of China. Left-behind adolescents completed a battery of self-report questionnaires regarding peer victimization, maternal control, self-injury behaviors, depression, and loneliness. Results The hierarchical multiple regressions indicated that both peer victimization and maternal psychological control were positively associated with self-injury behaviors, depression, and loneliness. Moreover, maternal behavioral control played a dual role in the impact of peer victimization on self-injury behaviors depending on the levels of maternal psychological control. When left-behind women exerted high psychological control on their children, maternal behavioral control buffered the negative effect of peer victimization on self-injury behaviors. However, when left-behind women exerted low psychological control on their children, maternal behavioral control exacerbated the negative effect of peer victimization on self-injury behaviors. Conclusion These findings suggest that the effectiveness of behavioral control may depend on different situations, left-behind women should be cautious in exerting behavioral control over their children.

C-aryl glycosides are widely found in nature and play important roles in drug design. Despite the significant progress made over the past few decades, efficient and stereoselective synthesis of complex C-aryl glycosides remains challenging, lagging far behind the state of the art of the synthesis of O- or N-glycosides. Here, we report a simple and powerful bioinspired strategy for the stereoselective synthesis of C-aryl glycosides via palladium-catalysed ortho-directed C(sp2)−H functionalization of arenes and heteroarenes with easily accessible glycosyl chloride donors. The catalytic palladacycle intermediate generated via C−H palladation provides a soft aryl nucleophile that can react with glycosyl oxocarbenium ion partners with high efficiency and excellent stereocontrol. The method can be applied to a wide range of arene and heteroarene substrates, glycosyl chloride donors and auxiliary groups. It can simplify the synthesis of a variety of complex C-aryl glycosides and offers a tool for late-stage modification of drug molecules. C-aryl glycosides are present in many natural products and of interest in drug design, but their chemical synthesis is challenging. This work reports an efficient and diastereoselective ortho-directed C−H glycosylation of arenes and heteroarenes with glycosyl chloride using a palladium catalyst.

The tumor microenvironment (TME) is a unique niche governed by constant crosstalk within and across all intratumoral cellular compartments. In particular, intratumoral high potassium (K

Extinction angle control is one of the main control strategies to mitigate the commutation failure in HVDC, but the problem of insufficient response speed and control precision still can't be solved effectively based on the current research on measured and predictive extinction angle control. Thus, an improved extinction angle control method to mitigate subsequent commutation failure is proposed. Firstly, the influence of voltage harmonics on the commutation process of HVDC system is analyzed, and the prediction method of extinction angle considering the voltage harmonics is proposed. Then, the predictive value of the subsequent commutation process is introduced into the original control logic of the system to improve extinction angle control. Finally, the proposed control method is simulated and verified based on the standard test system. The simulation results show that the method can improve the response speed and control precision of the extinction angle control to a certain extent, and thus can effectively mitigate the subsequent commutation failure in HVDC.

(1) Purpose: Non-suicidal self-injury (NSSI) possibly emerges as well as remits in adolescence. To explore the development and transition of NSSI, this study examined the association between a wide range of interpersonal and intrapersonal predictors of NSSI initiation and cessation. (2) Methods: Chinese adolescents (N = 913) completed self-reported surveys at baseline and at a six-month follow-up. The sample included 625 adolescents who reported no NSSI and 288 adolescents who reported engagement in NSSI at baseline. (3) Results: Among the adolescents without NSSI at baseline, 24.3% engaged in NSSI at follow-up (NSSI initiation group). Among the adolescents with NSSI at baseline, 33.3% reported no NSSI at follow-up (NSSI cessation group). Loneliness, beliefs about adversity, problem behavior, and prosocial behavior were the significant factors in predicting subsequent NSSI initiation. None of the potential predicting factors were associated with subsequent NSSI cessation. (4) Conclusions: These results indicate the importance of intrapersonal factors in Chinese culture, which could be used to identify at-risk adolescents and to design interventions.

Commutation failure (CF) is one of the most common faults in traditional HVDC system. Effective prediction of CF is beneficial to the safety and stability of the power system. The physical-driven prediction method can effectively reflect the causal law but it is difficult to establish a precise model. Data-driven prediction method has the advantage of efficient training, but the prediction accuracy depends on a large number of high-quality training samples. Combining the advantage of physical-driven and data-driven methods, a CF prediction method is proposed. In the physical-driven part, the inherent response of the power system is transformed from time-domain to frequency-domain to obtain the predicted commutation voltage. Then the predicted DC current can be obtained based on the superposition theorem. Finally, the predicted extinction angle can be calculated according to the commutation mechanism. In the part of data-driven, the amplitude and phase of each harmonic of the commutation voltage are taken as the input characteristics, and the extinction angle predicted by the physi-cal-driven method can be modified. According to the results of the test system built in electromagnetic transient simulation software, the validation of the proposed method is verified.