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We reveal an excited-state photochemical reaction mechanism for monolayer WSe2 under the Mott density condition, which could be used as an electronic state criterion for femtosecond-laser modified monolayer transition metal dichalcogenides.

A dynamic and reconfigurable satellite-to-ground communication system research based on LoRa technology is proposed in this paper. Starting from the application background of the internet of things (IoT) on the low earth orbit (LEO) satellite, this paper proposes a modulation parameter dynamic and reconfigurable technology for the Long Range (LoRa) signal, so as to improve the reliability of the IoT used in the satellite-to-ground communication system. Then, a parameter reconstitution method is designed in detail according to the satellite-to-ground communication link budget, and this method has the advantages of low complexity and less resources. Meanwhile, in this communication system, a desired bit rate can be selected based on the parameter reconstitution method to support different application. Simulation results show that the dynamic and reconfigurable satellite-to-ground communication system can work as expected, and this research possesses a great guidance in making the space-based IoT.

The non-volatile resistive switching process of a MoS2 based atomristor with a vertical structure is investigated by first-principles calculations. It is found that the monolayer MoS2 with S vacancy defects (Vs) could maintain an insulation characteristic and a high resistance state (HRS) is also remained. As an electrode metal atom adsorbed on MoS2 monolayer, the semi-conductive filament is formed with the assistance of Vs. Under this condition the atomristor presents a low resistance state (LRS). The ON state current of this semi-filament is increased close to two orders than that of without filament (HRS). The energy barrier for an Au-atom to penetrate the monolayer MoS2 via Vs is as high as 6.991 eV. When it comes to double S vacancy (Vs2), the energy barrier is still amounted to 3.554 eV, which manifests the bridge-like full conductive filaments cannot form in monolayer MoS2 based atomristor. The investigation here promotes the atomistic understanding of the resistive switching properties about the monolayer MoS2 based memristor. The physics behind should also work in atomristors based on other monolayer transitional metal dichalcogenides, like WeSe2 and MoTe2. The investigation here will promote the comprehension of these devices at atomic scale and be a reference for device design or optimization.

Electronic states are significantly correlated with chemical compositions, and the information related to these factors is especially crucial for the manipulation of the properties of matter. However, this key information is usually verified by after-validation methods, which could not be obtained during material processing, for example, in the field of femtosecond laser direct writing inside materials. Here, critical evolution stages of electronic states for monolayer tungsten diselenide (WSe

Ultrafast laser-induced phase/structural transitions show a great potential in optical memory and optical computing technologies, which are believed to have advantages of ultrafast speed, low power consumption, less heat diffusion and remote control as compared with electronic devices. Here, we review and discuss the principles of orbital-selective electronic excitation and its roles in phase/structural transitions of phase-change memory (PCM) materials, including Sc0.2Sb1.8Te3 and GeTe phases. It is demonstrated, that the mechanism can influence the dynamics or results of structural transitions, such as an ultrafast amorphization of Sc0.2Sb1.8Te3 and a non-volatile order-to-order structural transition of GeTe. Without thermal melting, these structural transitions have the advantages of ultrafast speed and low power consumption. It suggests that the orbital-selective electronic excitation can play a significant role in discovering new physics of phase change and shows a potential for new applications.

Proteins do not only serve as nutrients to fulfill the demand for food, but also are used as a source of bioactive proteins/polypeptides for regulating physical functions and promoting physical health. Female breast cancer has the highest incidence in the world and is a serious threat to women's health. Bioactive proteins/polypeptides exert strong anti-tumor effects and exhibit inhibition of multiple breast cancer cells. This review discussed the suppressing effects of bioactive proteins/polypeptides on breast cancer in vitro and in vivo, and their mechanisms of migration and invasion inhibition, apoptosis induction, and cell cycle arrest. This may contribute to providing a basis for the development of bioactive proteins/polypeptides for the treatment of breast cancer.

Our study focused on childhood emotional neglect and several forms of abuse (i.e., physical, sexual, and emotional) and the diagnosis and clinical courses of disease in Chinese adults with major depressive disorder (MDD), including MDD with anxiety, with suicidality, and with other presentations. MDD and other clinical presentations were determined with the American Psychiatric Association’s (2000) Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) and subtypes of trauma were assessed with the Childhood Trauma Questionnaire (95 patients and 94 comparisons). Patients with MDD and suicidality scored higher on childhood emotional abuse and neglect than other MDD patients. Both emotional abuse and physical abuse correlated with a younger age of onset and more relapses of MDD. General linear modeling also showed that controlling for demographic variables, emotional and physical abuse predicted more MDD relapses. Overall, childhood trauma was correlated with a MDD diagnosis, the role of specific types of trauma in the clinical courses of MDD varied.

The appearance of van der Waals heterostructures offers a new solution to valleytronics. Here, we observe the spin-valley depolarization process of electrons and holes in type-II MoS

Two-dimensional (2D) materials are no doubt the most widely studied nanomaterials in the past decade. Most recently, a new type of 2D material named the double-layer honeycomb (DLHC) structure opened a door to achieving a series of 2D materials from traditional semiconductors. However, as a newly developed material, there still lacks a timely understanding of its structure, property, applications, and underlying mechanisms. In this review, we discuss the structural stability and experimental validation of this 2D material, and systematically summarize the properties and applications including the electronic structures, topological properties, optical properties, defect engineering, and heterojunctions. It was concluded that the DLHC can be a universal configuration applying to III–V, II–VI, and I–VII semiconductors. Moreover, these DLHC materials indeed have exotic properties such as being excitonic/topological insulators. The successful fabrication of DLHC materials further demonstrates it is a promising topic. Finally, we summarize several issues to be addressed in the future, including further experimental validation, defect engineering, heterojunction engineering, and strain engineering. We hope this review can help the community to better understand the DLHC materials timely and inspire their applications in the future.

Objectives: This study is aimed to examine the potential association between childhood trauma (CT) and personality traits among unaffected first-degree relatives (FDR, children or siblings of patients) of patients with major depressive disorder (MDD). Methods: The study consists of three groups: total 85 patients with MDD, 35 FDRs and 89 healthy control individuals (HC). The Childhood Trauma Questionnaire (CTQ) was used to assess childhood trauma and the Eysenck Personality Questionnaire used to assess personality traits. Results: By comparison made in personality traits, MDD patients exhibits some significant disparities to FDR and HC (pConclusion: CT was associated with N, P and L, with a closer relation to N in unaffected FDR. Besides, the type of CT, the most relevant to N, was discovered to be EN. Thus, FDR of MDD who experienced CT should be prioritized. Key words: childhood trauma; personality; major depressive disorder; first-degree relatives

Abstrac Objectives This study aimed to preliminarily and exploratorily examine the associations between childhood trauma (CT), its subtypes, and personality traits among unaffected first-degree relatives (FDR, children, or siblings) of patients with major depressive disorder (MDD). Methods The study sample included three subgroups: MDD patients (N = 85), Patients’ FDRs (N = 35), and healthy control individuals (HC, N = 89). The Childhood Trauma Questionnaire (CTQ) was used to assess childhood trauma and the Eysenck Personality Questionnaire was used to assess personality traits. Results Significant differences were found in a few personality traits (p F = 3.246, p = 0.046). CT was significantly associated with N, psychoticism (P) and Lie (L), and the strongest association was between CT total score and N. Significantly positive correlations were found between N and sexual abuse (SA) (r = 0.344, p = 0.043), emotional neglect (EN) (r = 0.394, p = 0.019), physical neglect (PN) (r = 0.393, p = 0.019), and CTQ total score (r = 0.452, p = 0.006); between P and CTQ total score (r = 0.336, p = 0.049); and significant negative correlations were found between L and EN (r = -0.446, p = 0.007), CTQ total score (r = -0.375, p = 0.027). Conclusion In unaffected FDRs, there were significant associations between childhood trauma and a few personality traits, including neuroticism, psychoticism, and lie, and emotional neglect was significantly associated with neuroticism.

Schizophrenia is a severe mental disorder, and the onset of which is preceded by a stage of ultrahigh risk (UHR) for developing psychosis. Therefore, analyzing individuals with UHR is essential for identifying predictive biomarkers for the onset of schizophrenia. The current study aimed to identify such biomarkers based on a voxelwise whole-brain functional degree centrality (FDC) analysis. Conjunction analysis showed that, compared with healthy controls, both UHR subjects and patients with schizophrenia showed significantly increased FDC at the medial prefrontal cortex (MPFC) and significantly decreased FDC at the right fusiform gyrus (FG). The subsequent partial correlation analysis showed significant correlations between the disorganization symptoms and FDCs at the MPFC and the right FG for both UHR subjects and patients with schizophrenia. These findings suggest that FDC within the MPFC and the right FG could be candidate biomarkers for the onset of schizophrenia.

Background Results of previous studies on the safety and efficacy of adjunctive reboxetine for schizophrenia have been inconsistent. Aim The aim of this study was to examine the efficacy and tolerability of reboxetine as an adjunct medication to antipsychotic treatment in a meta-analysis of randomized controlled trials (RCTs). Methods Two independent investigators extracted data for a random effects meta-analysis and assessed the quality of studies using risk of bias and the Jadad scale. Weighted and standardized mean differences (WMDs/SMDs) and risk ratio (RR)±95% confidence intervals (CIs) were calculated. Results Nine RCTs (n=630) with double-blind design were identified. Reboxetine outperformed placebo in improving negative (9 RCTs, n=602, SMD: −0.47 [95% CI: −0.87, −0.07], p=0.02; I2=82%), but not the overall, positive, and general psychopathology scores. The significant therapeutic effect on negative symptoms disappeared in the sensitivity analysis after removing an outlying study and in 50% (6/12) of the subgroup analyses. Reboxetine outperformed placebo in reducing weight (3 RCTs, n=186, WMD: −3.83 kg, p=0.04; I2=92%) and body mass index (WMD: −2.23 kg/m2, p=0.04; I2=95%). Reboxetine caused dry mouth but was associated with less weight gain overall and weight gain of ≥7% of the initial weight. All-cause discontinuation and other adverse events were similar between reboxetine and placebo. Conclusion Adjunctive reboxetine could be useful for attenuating antipsychotic-induced weight gain, but it was not effective in treating psychopathology including negative symptoms in schizophrenia.

We fabricated the amorphous GeTe/cubic Sb2Te3 supperlattice-like structure films by the radio frequency sputtering, and demonstrated the stability of cubic Sb2Te3 could be strengthened. The competition between interface energy and phase transformation energy resulted in the thermodynamical stability at the nanoscale. The presented design approach opens the doors for the stabilization of metastable phase, and sheds new insights into the role of interfaces in materials synthesis.

Atomic picture and electronic transport property are taken into account to investigate the nonvolatile resistive switching mechanism of a memristor at the thinnest limit, just based on one monolayer hexagonal boron nitride ( h-BN). It is demonstrated that the intrinsic van der Waals gaps between electrodes and monolayer h-BN ensure the high resistance state (HRS). However, the absorption/desorption of a metallic-electrode atom on the one side of the h-BN can hardly switch the device to hold the experimentally observed ON/OFF current ratio. It is proposed that the electrode atom should penetrate the h-BN sheet via boron vacancy ([Formula: see text]) to form a full conductive atomic filament for an effective low resistance state. The current signal of this [Formula: see text] pinning Au conductive filament can reach up to three orders of magnitude higher than that of the HRS. The energy barrier for one Au atom to pass through [Formula: see text] is also reasonably as low as 0.832 eV. Molecular dynamics simulation further manifests the nonvolatility of this atomic conductive filament at the limit that could even maintain stability at 500 K. This work offers a key working picture in memristors at their thinnest limit, which provides a valuable reference to the development of emerging memory/computing devices at the ultrathin scale.

It remains a remarkable challenge to develop practical techniques for controllable and nondestructive doping in two-dimensional (2D) materials for their use in electronics and optoelectronics. Here, we propose a modulation doping strategy, wherein the perfect n-/p-type channel layer is achieved by accepting/donating electrons from/to the defects inside an adjacent encapsulation layer. We demonstrate this strategy in the heterostructures of BN/graphene, BN/MoS2, where the previously believed useless deep defects, such as the nitrogen vacancy in BN, can provide free carriers to the graphene and MoS2. The carrier density is further modulated by engineering the surroundings of the encapsulation layer. Moreover, the defects and carriers are naturally separated in space, eliminating the effects of Coulomb impurity scattering and thus allowing high mobility in the 2D limit. This doping strategy provides a highly viable route to tune 2D channel materials without inducing any structural damage, paving the way for high-performance 2D nanoelectronic devices.

One central task of developing nonvolatile phase change memory (PCM) is to improve its scalability for high‐density data integration. In this work, by first‐principles molecular dynamics, to date the thinnest PCM material possible (0.8 nm), namely, a monolayer Sb2Te3, is proposed. Importantly, its SET (crystallization) process is a fast one‐step transition from amorphous to hexagonal phase without the usual intermediate cubic phase. An increased spatial localization of electrons due to geometrical confinement is found to be beneficial for keeping the data nonvolatile in the amorphous phase at the 2D limit. The substrate and superstrate can be utilized to control the phase change behavior: e.g., with passivated SiO2 (001) surfaces or hexagonal Boron Nitride, the monolayer Sb2Te3 can reach SET recrystallization in 0.54 ns or even as fast as 0.12 ns, but with unpassivated SiO2 (001), this would not be possible. Besides, working with small volume PCM materials is also a natural way to lower power consumption. Therefore, the proposed PCM working process at the 2D limit will be an important potential strategy of scaling the current PCM materials for ultrahigh‐density data storage., By first‐principles molecular dynamics, this work proposes a phase change memory (PCM) process at the 2D limit that is achieved in a monolayer Sb2Te3 for the first time. This will be a potential strategy for improving the performance of PCM technology to realize high integrated density, fast speed, low power consumption, or even artificial intelligence applications.

Direct optical ferroelectric switching (FE switch) has the advantage of being ultrafast over the traditional FE switch, which relies on domain nucleation and growth. However, how to realize nonvolatility in such an optical FE switch poses a serious challenge. Time-dependent density-functional theory molecular dynamics study reveals that subpicosecond nonvolatile FE switches can be realized in GeTe and ${\mathrm{PbTiO}}_{3}$. While optical tuning of the transition barrier and initiation of a directional atomic motion are crucial, the dephasing of the excited state holds the key for the realization of nonvolatility.

Many robust studies have investigated prepulse inhibition (PPI) in patients with schizophrenia. Recent evidence indicates that PPI may help identify individuals who are at clinical high risk for psychosis (CHR). Selective attention to prepulse stimulus can specifically enhance PPI in healthy subjects; however, this enhancement effect is not observed in patients with schizophrenia. Modified PPI measurement with selective attentional modulation using perceived spatial separation (PSS) condition may be a more robust and sensitive index of PPI impairment in CHR individuals. The current study investigated an improved PSSPPI condition in CHR individuals compared with patients with first-episode schizophrenia (FES) and healthy controls (HC) and evaluated the accuracy of PPI in predicting CHR from HC. We included 53 FESs, 55 CHR individuals, and 53 HCs. CHRs were rated on the Structured Interview for Prodromal Syndromes. The measures of perceived spatial co-location PPI (PSCPPI) and PSSPPI conditions were applied using 60- and 120-ms lead intervals. Compared with HC, the CHR group had lower PSSPPI level (Inter-stimulus interval [ISI] = 60 ms, P < .001; ISI = 120 ms, P < .001). PSSPPI showed an effect size (ES) between CHR and HC (ISI = 60 ms, Cohen’s d = 0.91; ISI = 120 ms, Cohen’s d = 0.98); on PSSPPI using 60-ms lead interval, ES grade increased from CHR to FES. The area under the receiver operating characteristic curve for PSSPPI was greater than that for PSCPPI. CHR individuals showed a PSSPPI deficit similar to FES, with greater ES and sensitivity. PSSPPI appears a promising objective approach for preliminary identification of CHR individuals.

Objective: To evaluate the neglect of left-behind children (LBC) in China. Method: Participants: Children separated from one or both parents for at least 6 months. Intervention: Trauma of separation. Comparison: Non-left-behind children (NLBC). Outcomes: Neglect rates and severity. Only case–control studies were included. Results: Thirteen studies were included; there were 18,688 LBC in a large sample ( N = 42,003) of children aged 0–18 years in China. The overall neglect rate was significantly higher in LBC compared to NLBC (odds ratio [ OR] = 1.58, 95% confidence interval [CI] = [1.50, 1.67], p < .01) based on the Chinese Rural Child Neglected Evaluation Model (CRCNEM) and the Parents–Child Conflict Tactics Scales ( OR = 1.44, 95% CI [1.35, 1.54], p < .01). The overall neglect severity in LBC was also significantly higher than NLBC ( SMD = 0.31, 95% CI [0.28, 0.33], p < .01). The same trends were observed in sex subgroups. With regard to subtypes, LBC were significantly more likely to have emotional neglect ( OR = 2.29, 95% CI [1.88, 2.78], p < .01), medical neglect ( OR = 1.79, 95% CI [1.62, 1.98], p < .01), physical neglect ( OR = 1.75, 95% CI [1.60, 1.91], p < .01), security neglect ( OR = 1.52, 95% CI [1.32, 1.75], p < .01), educational neglect ( OR = 1.50, 95% CI [1.31, 1.72], p < .01), and social neglect ( OR = 1.33, 95% CI [1.18, 1.51], p < .01). Furthermore, LBC had significantly higher severity in medical neglect ( SMD = 0.31, 95% CI [0.27, 0.35], p < .01), emotional neglect ( SMD = 0.28, 95% CI [0.24, 0.32], p < .01), physical neglect ( SMD = 0.24, 95% CI [0.18, 0.29], p < .01), security neglect ( SMD = 0.26, 95% CI [0.23, 0.29], p < .01), educational neglect ( SMD = 0.25, 95% CI [0.20, 0.31], p < .01), and social neglect ( SMD = 0.25, 95% CI [0.10, 0.40], p < .01). Conclusion: The neglect rates and severity in LBC in China were both significantly higher than those in NLBC. There was a strong association between neglect and LBC. Public policy changes are urgently needed to improve the dire situation and the well-being of the LBC.

npj computational materials 6(1), 31 (2020). doi:10.1038/s41524-020-0303-z, Published by Nature Publ. Group, London

AIM The extent and specifics regarding cognitive dysfunction in patients with bipolar disorder (BD) or major depressive disorder (MDD) and their unaffected first-degree relatives (FDR) have not been addressed in any single study. The present study compared the cognitive function of patients with BD or MDD, their FDR, and healthy control (HC) individuals. METHODS The study population comprised adults (aged 18-55 years) with BD, adults with MDD, FDR (children or siblings of patients with BD or MDD), and HC (n = 105, 109, 85, and 95, respectively). The Repeatable Battery for the Assessment of Neuropsychological Status was used to assess neurocognitive functions, with five domains and 12 tests. A Wechsler Adult Intelligence Scale brief form was applied to evaluate IQ. Status of mood was assessed using the Young Mania Rating Scale and the Hamilton Depression Scale. RESULTS The mixed model indicated significant variation among the four groups in cognitive function. Cognitive impairments, compared to HC, progressively greater from least to most were found in: FDR, MDD, and BD (F = 32.74, P < 0.001). Years of education correlated with cognitive performance (F = 17.04, P < 0.001), as did IQ (F = 240.63, P < 0.001). The total score for the Hamilton Rating Scale for Depression negatively correlated with cognitive function (F = 5.78, P = 0.017). CONCLUSION Among the study groups, patients with BD had the most severe deficits, followed by MDD patients and FDR. Cognitive deficits could not be associated with a specific psychiatric disorder, but differences in degree were noted.

A crystalline silicon (Si) surface was modified using nanosecond laser pulses in an argon atmosphere. The laser-modified Si (M-Si) samples have a higher performance and thermostable absorption in the broadband range (400–2400 nm) than conventional Si. The concentration of carrier electrons in the M-Si layer is at least five orders of magnitude greater than the carrier concentration of the Si substrate. Using the N+–N− junction formed between the M-Si layer and the Si substrate, visible and near-infrared (VIS-NIR) M-Si photodetectors are made. The N+–N− photodiode has good rectification characteristics and a high photoresponse to the subbandgap NIR light at 1310 nm. At the same time, the M-Si photodetector at a low reverse bias shows a large gain to the VIS-NIR light above the bandgap. By comparing the response time of the M-Si photodetector to the light of 900 and 1310 nm, the response speed of the device to the photon above-bandgap energy is faster.

Lurasidone, an azapirone derivative, is a novel second generation antipsychotic with potent binding affinity for dopamine D2, serotonin 5-HTDouble-blinded RCTs reporting on the short-term effects of lurasidone were included. Standardized mean difference (SMD) with their 95% confidence interval (CI), and number needed to harm (NNH) were computed.The meta-analysis had 8 RCTs with 16 active arms that included 2373 patients with acute schizophrenia who were randomized to either lurasidone (20-160 mg/day; n = 1570) or placebo (n = 803) groups. Lurasidone was superior to placebo with regard to change in total psychopathology [SMD: -0.34, (95%CI: -0.48, -0.20), P0.00001], positive symptoms [SMD: -0.47, (95%CI: -0.57, -0.36), P0.00001], negative symptoms [SMD:-0.34, (95%CI: -0.45, -0.22), P0.00001], and general psychopathology [SMD: -0.36, (95%CI: -0.48, -0.24), P0.00001]. Results were consistent for total psychopathology in 11 out of the 13 subgroups. Lurasidone resulted in higher weight gain [SMD: 0.15, (95% CI: 0.06, 0.24), P = 0.001] and BMI [SMD: 0.17, (95%CI: 0.07, 0.28), P = 0.002] than placebo, but the differences were not clinically significant. Lurasidone group had less frequent inefficacy (NNH = 14) and discontinuation due to any reason (NNH = 17), but was associated with more frequent vomiting, akathisia, dystonia, parkinsonism, somnolence, dizziness, sedation, nausea, and weight gain of ≥7% of the initial weight (NNH = 11-50).This meta-analysis of 8 short-term studies supported the efficacy and safety of lurasidone in the acute phase of schizophrenia, particularly at the higher dose range of 80 mg/day.

Micro-ripple and micro-bead structures are formed on a silicon (Si) surface after irradiation with femtosecond laser pulses in nitrogen (N2) atmosphere. Simultaneously, supersaturated nitrogen (N) atoms, with a concentration above 1020 cm−3, are doped into the textured black Si layer via laser ablation. The N-doped Si exhibits strong below-bandgap infrared absorption from 1.1 to $2.5~\mu \text{m}$ , which remains nearly unchanged after annealing for 30 min at 873 K. The mechanism of this thermally stable infrared absorption is analyzed by first-principles calculations. According to the transmission electron microscopy results, multiple phases (including single crystalline, nanocrystalline, and amorphous phases) are observed in the laser-irradiated layer. Hall Effect measurements prove that N-dopants induce a low background free-carrier concentration ( $\sim 1.67\times 10^{16}\,\,\text {cm}^{-3}$ ). Finally, a Schottky-based bulk structure photodiode is made. This broadband photodiode exhibits good thermal stability and a photo-responsivity of 5.3 mA/W for $1.31~\mu \text{m}$ at a reverse bias of 10 V.

Understanding how the structures of a crystal behave under compression is a fundamental issue both for condensed matter physics and for geoscience. Traditional description of a crystal as the stack...

Phase-change memory (PCM) material is the promising material system for nonvolatile-memory technology. Performance optimization of PCM device urgently requires the deeper clarification of its material “Gene”. In this study, through first-principles calculations, p-orbital-aligned atom chains are identified to play important roles in governing optoelectronic reflectivity in amorphous Ge2Sb2Te5. These atom chains make the electronic state of the amorphous Ge2Sb2Te5 hold strong electron-polarized components, thereby governing the optical property. The present study offers a new understanding of “Gene” for PCM materials which benefit the material design and the performance improvement of PCM devices.

Ge–Sb–Te superlattice (GST-SL) is a newly emerging electronic material for nonvolatile phase-change memory with ultralow energy cost. However, its switching mechanism is still unclear with intensive debates. In this work, by first-principles calculations and an electron counting model study, we study the possible mechanism of phase change and the accompanying property transition of GST-SL. GST-SL are separated into individual layers by van der Waals gaps. We demonstrate that both the global chemical stoichiometry of the material and the local chemical stoichiometry of individual layer block are required to have an insulating band gap according to an electron counting model analysis. The electrical property can be adjusted by changing the local stoichiometry, such as producing defects around van der Waals gaps. Inspired by a previous experiment, we propose that a stacking-fault motion can spontaneously alter the band gap and results in a metal–insulator transition. This transition may provide a significant change of carrier concentration and indicate an ultralow energy-consumption process with a low energy barrier. The present investigations reveal a picture of electrical transition in GST-SL and may guide us to improve its device performances.