Giant spin-orbit splitting of point defect states in monolayer WS2_2

The spin-orbit coupling (SOC) effect has been known to be profound in monolayer pristine transition metal dichalcogenides (TMDs). Here we show that point defects, which are omnipresent in the TMD membranes, exhibit even stronger SOC effects and change the physics of the host materials drastically. In this Article we chose the representative monolayer WS\sub{2} slabs from the TMD family together with seven typical types of point defects including monovacancies, interstitials, and antisites. We calculated the formation energies of these defects, and studied the effect of spin-orbit coupling (SOC) on the corresponding defect states. We found that the S monovacancy (V\sub{S} ) and S interstitial (adatom) have the lowest formation energies. In the case of V\sub{S} and both of the W\sub{S and W\sub{S2} antisites, the defect states exhibit giant splitting up to 296 meV when SOC is considered. Depending on the relative position of the defect state with respect to the conduction band minimum (CBM), the hybrid functional HSE will either increase the splitting by up to 60 meV (far from CBM), or decrease the splitting by up to 57 meV (close to CBM). Furthermore, we found that both the W\sub{S} and W\sub{S2} antisites possess a magnetic moment of 2 $\mu_{B}$ localized at the antisite W atom and the neighboring W atoms. All these findings provide new insights in the defect behavior under SOC point to new possibilities for spintronics applications for TMDs.Comment: 8 pages, 6 figure

The neural basis of responsibility attribution in decision-making

Social responsibility links personal behavior with societal expectations and plays a key role in affecting an agent's emotional state following a decision. However, the neural basis of responsibility attribution remains unclear. In two previous event-related brain potential (ERP) studies we found that personal responsibility modulated outcome evaluation in gambling tasks. Here we conducted a functional magnetic resonance imaging (fMRI) study to identify particular brain regions that mediate responsibility attribution. In a context involving team cooperation, participants completed a task with their teammates and on each trial received feedback about team success and individual success sequentially. We found that brain activity differed between conditions involving team success vs. team failure. Further, different brain regions were associated with reinforcement of behavior by social praise vs. monetary reward. Specifically, right temporoparietal junction (RTPJ) was associated with social pride whereas dorsal striatum and dorsal anterior cingulate cortex (ACC) were related to reinforcement of behaviors leading to personal gain. The present study provides evidence that the RTPJ is an important region for determining whether self-generated behaviors are deserving of praise in a social context

The origin of bias independent conductance plateaus and zero bias conductance peaks in Bi2Se3/NbSe2 hybrid structures

Superconducting proximity effect (SPE) in topological insulator (TI) and superconductor (SC) hybrid structure has attracted intense attention in recent years in an effort to search for mysterious Majorana fermions (MFs) in condensed matter systems. Here we report on the SPE in a Bi2Se3/NbSe2 junction fabricated with an all-dry transfer method. Resulting from the highly transparent interface, two sharp resistance drops are observed at 7 K and 2 K, respectively, corresponding to the superconducting transition of NbSe2 flake and the SPE induced superconductivity in Bi2Se3 flake. Experimentally measured differential conductance spectra exhibit a bias-independent conductance plateau (BICP) in the vicinity of zero bias below 7 K. As temperatures further decrease a zero bias conductance peak (ZBCP) emerges from the plateau and becomes more enhanced and sharpened at lower temperatures. Our numerically simulated differential conductance spectra reproduce the observed BICP and ZBCP and show that the SPE in topological surface states (TSS) is much stronger than that in the bulk states of Bi2Se3. The SPE induced superconducting gap for the TSS of Bi2Se3 is comparable to that of NbSe2 and gives rise to the observed BICP below 7 K. In contrast, the SPE induced superconducting gap for the bulk states of Bi2Se3 is an order of magnitude smaller than that of NbSe2 and superconducting TSS. These weakly paired bulk states in Bi2Se3 give rise to the ZBCP below 2 K. Our study has clearly unveiled the different roles of TSS and bulk stats in SPE, clarified the physical origin of the SPE induced features, and shined light on further investigation of SPE and MF in TI/SC hybrid structures

Hope Mitigates Depression throughout Adversities: The Immediate and Longitudinal Mediation of Flow

Positive psychology constructs such as hope and flow build resilience against psychological distress in major adversities, but it remains unknown how they interact to exert the protective effects. Taking advantage of the lifting of the “Zero-COVID” policy in December 2022 in mainland China, the current study incorporated a cross-sectional survey (study 1, n = 1185) and a longitudinal survey (n = 296) to investigate the interaction of these two factors in reducing depression during the COVID-lockdown and after the lockdown was finally abandoned. The results showed that hope during COVID-lockdown predicted concomitant flow experience and depression, and proactively predicted depression measured three months after the lockdown was lifted. Moreover, flow experience mediated the cross-sectional and longitudinal hope effects. These findings shed light on the inner dynamics of positive psychology constructs in protecting well-being, and are implicative for mental health intervention in disaster relief

The Influence of Harsh Parenting on Adolescent Anxiety: The Sequential Mediating Roles of Interpersonal Sensitivity and Ego-Depletion

Harsh parenting, characterized by punitive and controlling behaviors, has been increasingly linked to the development of anxiety disorders in adolescents. This study explores the mechanisms through which harsh parenting contributes to adolescent anxiety, focusing on the sequential mediation of Interpersonal Sensitivity (IS) and ego depletion. Drawing on the Emotion Dysregulation Model of Anxiety (EDMA), we propose that harsh parenting disrupts emotional regulation by fostering heightened IS, which, in turn, depletes self-control resources, exacerbating anxiety. Using a chain mediation model, we hypothesize that (1) harsh parenting positively correlates with adolescent IS, (2) ego depletion mediates the relationship between harsh parenting and anxiety, and (3) IS and ego depletion sequentially mediate this relationship. By examining these interconnected pathways, the study aims to provide insights into the underlying processes contributing to adolescent anxiety and offer valuable directions for early interventions aimed at improving mental health outcomes in adolescents

Nutlin-3 overcomes arsenic trioxide resistance and tumor metastasis mediated by mutant p53 in Hepatocellular Carcinoma

Background: Arsenic trioxide has been demonstrated as an effective anti-cancer drug against leukemia and solid tumors both in vitro and in vivo. However, recent phase II trials demonstrated that single agent arsenic trioxide was poorly effective against hepatocellular carcinoma (HCC), which might be due to drug resistance. Methods: Mutation detection of p53 gene in arsenic trioxide resistant HCC cell lines was performed. The therapeutic effects of arsenic trioxide and Nutlin-3 on HCC were evaluated both in vitro and in vivo. A series of experiments including MTT, apoptosis assays, co-Immunoprecipitation, siRNA transfection, lentiviral infection, cell migration, invasion, and epithelial-mesenchy-mal transition (EMT) assays were performed to investigate the underlying mechanisms. Results: The acquisition of p53 mutation contributed to arsenic trioxide resistance and enhanced metastatic potential of HCC cells. Mutant p53 (Mutp53) silence could re-sensitize HCC resistant cells to arsenic trioxide and inhibit the metastatic activities, while mutp53 overexpression showed the opposite effects. Neither arsenic trioxide nor Nutlin-3 could exhibit obvious effects against arsenic trioxide resistant HCC cells, while combination of them showed significant effects. Nutlin-3 can not only increase the intracellular arsenicals through inhibition of p-gp but also promote the p73 activation and mutp53 degradation mediated by arsenic trioxide. In vivo experiments indicated that Nutlin-3 can potentiate the antitumor activities of arsenic trioxide in an orthotopic hepatic tumor model and inhibit the metastasis to lung. Conclusions: Acquisitions of p53 mutations contributed to the resistance of HCC to arsenic trioxide. Nutlin-3 could overcome arsenic trioxide resistance and inhibit tumor metastasis through p73 activation and promoting mutant p53 degradation mediated by arsenic trioxide

Highly toughened polylactide with novel sliding graft copolymer by in situ reactive compatibilization, crosslinking and chain extension

YesThe “sliding graft copolymer” (SGC), in which many linear poly-ε-caprolactone (PCL) side chains are bound to cyclodextrin rings of a polyrotaxane (PR), was prepared and employed to toughen brittle polylactide (PLA) with methylene diphenyl diisocyanate (MDI) by reactive blending. The SGC was in situ crosslinked and therefore transformed from a crystallized plastic into a totally amorphous elastomer during reactive blending. Meanwhile, PLA-co-SGC copolymer was formed at interface to greatly improve the compatibility between PLA and SGC, and the chain extension of PLA also occurred, were confirmed by FTIR, GPC, SEM, and TEM. The resulting PLA/SGC/MDI blends displayed super impact toughness, elongation at break and nice biocompatibility. It was inferred from these results the crosslinked SGC (c-SGC) elastomeric particles with sliding crosslinking points performed as stress concentrators and absorbed considerable energy under impact and tension process.This work was supported by the National Natural Science Foundation of China (50933001, 51221002 and 51320105012)

Relationship between Chinese and International Crude Oil Prices: A VEC-TARCH Approach

Many studies focus on the impact of international crude oil price volatility on various economic variables in China with a hypothesis that international crude oil price affected Chinese crude oil price first and then other economic variables. However, there has been little research to explore whether or not international and Chinese oil market are integrated. This study aims to investigate the relationship between Chinese and international crude oil prices by VAR and VEC-TARCH models. It was found that the two crude oil markets have been integrated gradually. But the impact of external shocks on the Chinese crude oil market was stronger and the Chinese crude oil price was sensitive to changes in international crude oil price, implying that the centrally controlled oil market in China is less capable of coping with external risk. In addition, the volatility of both Chinese and international crude oil prices was mainly transmitted by prior fluctuation forecast and the impact of external shocks was limited, demonstrating that in both cases volatility would disappear rather slowly. Furthermore, Chinese and international crude oil markets have established a stable relationship. When the direction of external shocks on the two variables’ respective stochastic term was consistent, the impact on the two variables’ joint volatility was aggravated and vice versa