Improved Photovoltaic Performance of Inverted Two-Dimensional Perovskite Solar Cells via a Simple Molecular Bridge on Buried Interface.

NiOx-based two-dimensional perovskite solar cells (2D-PSCs) have the advantages of low fabrication temperature, suitable energy level matching, suppressed hysteresis, and superior stability, while the poor interfacial contacts between NiOx and perovskite layers limit the perovskite film growth and charge transfer. Herein, a simple molecule, urea, was used as a molecular modifier to form bifacial passivation on the buried interface of NiOx/perovskite, resulting in better interfacial contact and efficient bifacial passivation. We demonstrated that efficient bifacial passivation mainly comes from strong interactions between urea and NiOx or perovskite, which make urea a molecular bridge for smoother charge transfer. Moreover, urea can regulate the ratio of Ni3+/Ni2+, therefore boosting the conductivity of NiOx, and adjust the morphology of the NiOx film for better 2D-perovskite crystal growth. Besides, urea also passivates the bifacial defect states of both NiOx and perovskite film, yielding reduced defect density of the perovskite film and superior charge transfer on the buried interface. Consequently, inverted 2D-PSCs with urea modification proved significant improvements in short-circuit current density and fill factor, resulting in improved power conversion efficiency from 14.64 to 16.84% with better stability in air.

The prevalence of mpox and its association with sexual behavior among Chinese men who have sex with men in early August 2023.

Study investigating mpox infection and its association with sexual behavior among men who have sex with men (MSM) in China was lacking. This observational survey aimed to provide evidence on detail characteristics of mpox cases and sexual behavior, then analyze their relationship among MSM in China to help formulate prevention and control policies. An anonymous cross-sectional study was conducted in 27 MSM social organizations across 21 provinces, municipalities, and autonomous regions from July 31 to August 4, 2023. A safe sexual behavior index was constructed based on three risky sexual behaviors in the last month, including condomless anal intercourse, commercial sex and group sex. High safe sexual behavior indicated that the participant engaged in none of the three, and low safe sexual behavior indicated that they engaged in all three behaviors; otherwise, moderate safe sexual behavior was indicated. Among 7538 MSM, the prevalence of mpox was 0.73% (55/7538). The proportion of high safe sexual behavior was 79.64% (6003/7538). The crude prevalence of mpox was lower in the high safe sexual behavior group (0.35%, 21/6003), compared with the low (12.12%, 8/66) and moderate safe (1.78%, 26/1469) sexual behavior group. In the multivariable-adjusted analysis, after adjusting for all covariates, compared with low safe sexual behavior group, moderate safe sexual behavior group (aOR = 0.21; 95% CI = 0.08, 0.54) and high safe sexual behavior group (aOR = 0.04; 95% CI = 0.02, 0.12) both had lower risk of mpox. Of three sexual behaviors, MSM who reported no commercial sex had the lowest risk of mpox (aOR = 0.23; 95% CI = 0.13, 0.41), compared with those who reported commercial sex in the last month. The other two safe sexual behaviors both were associated with lower risk of mpox (no group sex vs. group sex: aOR = 0.15; 95% CI = 0.08, 0.28; no condomless anal intercourse vs. condomless anal intercourse: aOR = 0.23; 95% CI = 0.13, 0.41). The prevalence of mpox virus infection was nearly 1% among MSM in China. Strengthening mpox surveillance, emphasizing safe sexual behavior in health education are essential for the control of mpox among MSM in China.

Effects of contact tracing and nucleic acid testing on the COVID-19 outbreak in Zunyi, China: data-driven study using a branching process model.

BACKGROUND: During October 2021, China experienced localized outbreaks of COVID-19 in many cities. We analyzed the small local outbreak in Zunyi (Guizhou Province), a major city in southwestern China, and modeled the effects of different interventions on this outbreak. METHODS: Data on infections and contacts, provided by the Health Commission of Guizhou Province, were used to analyze the epidemiological characteristics of the outbreak and calculate the effectiveness of vaccination. A branching process model was used to simulate the outbreak. This model considered the time interval from exposure of the initial case to confirmation, the number of potential infections caused by the initial case, and the effects of the different interventions. RESULTS: From 18 to 25 October 2021, there were 12 patients with COVID-19 in Zunyi. Overall, the average age was 67.17 years-old, 8 patients were females, and 1 patient had an asymptomatic infection. The effectiveness of two-dose inactivated vaccine against SARS-CoV-2 infection was 16.7% (95% CI: 2.8% to 99.7%). The initial case was infected on 11 or 12 October 2021, 6.40 (95% CI: 6.37, 6.42; IQR: 4.92, 7.63) days before confirmation while the travelling in Lanzhou (Gansu Province). There were 10.07 (95% CI: 10.04, 10.09; IQR: 7.86, 11.93) potential secondary cases. When the effective vaccine coverage reached 60%, the probability of cumulative cases exceeding 20 was less than 8.77%, even if contact tracing was relaxed or eliminated. However, if the probability of tracing contacts decreased, earlier initiation of nucleic acid testing was necessary to control the outbreak. CONCLUSIONS: The COVID-19 outbreak in Zunyi was controlled quickly due to moderately effective vaccine coverage and rapid contact tracing. For controlling localized outbreaks, vaccination and contact tracing seemed to be more effective than massive nucleic acid testing in the initial phase of transmission. However, if there is low effective vaccine coverage or insufficient contact tracing, nucleic acid testing should start earlier.

Tuning Bienenstock-Cooper-Munro learning rules in a two-terminal memristor for neuromorphic computing.

In memristors, the implementation of the Bienenstock-Cooper-Munro (BCM) learning rule plays a significant role in the modulation balance of artificial synapses and the reduction of energy consumption owing to their sliding frequency threshold. At present, the BCM learning rule is mostly achieved by adjusting gating voltage or channel current in field effect transistors. However, owing to the lack of the tunable degrees of freedom, the progress of two-terminal memristors is limited to simulating the BCM learning rule. In this study, by adjusting the series resistance, three types of BCM-like learning rules are found in a two-terminal BaTiO3 memristor. Specifically, the abnormal BCM learning rule with high-frequency depression and low-frequency potentiation is obtained for a small series resistance, the monotonous BCM learning rule with high-frequency potentiation and low-frequency depression is achieved for a large series resistance, and the type of BCM learning rule with the enhanced depression effect is obtained for a moderate series resistance. These three BCM learning rules are related to the non-monotonous conductance modulation caused by the migration of ionized oxygen vacancies and are proved by X-ray photoelectron spectroscopy. Moreover, spike rate-dependent plasticity (SRDP) and history-dependent plasticity are achieved. This study offers promising prospects for neuromorphic computing.

Awareness of mpox-related knowledge among men who have sex with men in China.

BACKGROUND: With the rapid spread of the mpox epidemic, cases have emerged in multiple countries, mainly among men who have sex with men. Because of the connectedness of today's world, countries have to be prepared to face risks in advance. Therefore, this study aimed to investigate awareness of mpox-related knowledge among men who have sex with men in China. METHODS: With the assistance of the social organizations of men who have sex with men, a cross-sectional survey of men who have sex with men in China was conducted through an online questionnaire between July 1 and July 18, 2022. A nationwide sample of Chinese men who have sex with men (N = 3,257) was recruited. RESULTS: Only 36.9% of participants had mpox-related knowledge. Awareness of mpox-related knowledge among respondents was positively associated with those in older age groups (33 to 42 years and 51 years or older) (adjusted odds ratio [AOR] = 1.31; 95% confidence interval [CI]: 1.03-1.67, AOR = 1.61; 95% CI: 1.16-2.24; respectively), married (AOR = 1.55; 95% CI: 1.09-2.19), and those with a graduate degree or above (AOR = 2.14; 95% CI: 1.11-4.13), while negatively associated with those living in the western parts of China (AOR = 0.74; 95% CI: 0.60-0.92), and those who were unsure of their history of Human Immunodeficiency Virus (HIV) status (AOR = 0.44; 95% CI: 0.30-0.63). CONCLUSION: Mpox-related knowledge is fairly low among men who have sex with men in China. China needs to spread knowledge to the public through multiple channels, especially in key populations (men who have sex with men, HIV-infected, etc.), and take preventive measures to effectively avoid outbreaks of mpox.

Impact of pesticides exposure during neurodevelopmental period on autism spectrum disorders - A focus on gut microbiota.

Accumulating evidence indicates exposure to pesticides during the crucial neurodevelopmental period increases susceptibility to many diseases, including the neurodevelopmental disorder known as autism spectrum disorder (ASD). In the last few years, it has been hypothesized that gut microbiota dysbiosis is strongly implicated in the aetiopathogenesis of ASD. Recently, new studies have suggested that the gut microbiota may be involved in the neurological and behavioural defects caused by pesticides, including ASD symptoms. This review highlights the available evidence from recent animal and human studies on the relationship between pesticides that have the potential to disturb intestinal microbiota homeostasis, and ASD symptoms. The mechanisms through which gut microbiota dysbiosis may trigger ASD-like behaviours induced by pesticides exposure during the neurodevelopmental period via the altered production of bacterial metabolites (short chain fatty acids, lipids, retinol, and amino acid) are also described. According to recent research, gut microbiota dysbiosis may be a major contributor to the symptoms of ASD associated with pesticides exposure. However, to determine the detailed mechanism of action of gut microbiota on pesticide-induced ASD behaviours, actual population exposure scenarios from epidemiological studies should be used as the basis for the appropriate exposure pattern and dosage to be used in animal studies.

An efficient privacy-preserving blockchain storage method for internet of things environment.

Blockchain is a key technology to realize decentralized trust management. In recent studies, sharding-based blockchain models are proposed and applied to the resource-constrained Internet of Things (IoT) scenario, and machine learning-based models are presented to improve the query efficiency of the sharding-based blockchains by classifying hot data and storing them locally. However, in some scenarios, these presented blockchain models cannot be deployed because the block features used as input in the learning method are privacy. In this paper, we propose an efficient privacy-preserving blockchain storage method for the IoT environment. The new method classifies hot blocks based on the federated extreme learning machine method and saves the hot blocks through one of the sharded blockchain models called ElasticChain. The features of hot blocks will not be read by other nodes in this method, and user privacy is effectively protected. Meanwhile, hot blocks are saved locally, and data query speed is improved. Furthermore, in order to comprehensively evaluate a hot block, five features of hot blocks are defined, including objective feature, historical popularity, potential popularity, storage requirements and training value. Finally, the experimental results on synthetic data demonstrate the accuracy and efficiency of the proposed blockchain storage model.

The relationship between pesticide exposure during critical neurodevelopment and autism spectrum disorder: A narrative review.

Agricultural pesticides have been one of the most extensively used compounds throughout the world. The main sources of contamination for humans are dietary intake and occupational exposure. The impairments caused by agricultural pesticide exposure have been a significant global public health problem. Recent studies have shown that low-level agricultural pesticide exposure during the critical period of neurodevelopment (pregnancy and lactation) is closely related to autism spectrum disorder (ASD). Inhibition of acetylcholinesterase, gut microbiota, neural dendrite morphology, synaptic function, and glial cells are targets for the effects of pesticides during nervous system development. In the present review, we summarize the associations between several highly used and frequently studied pesticides (e.g., glyphosate, chlorpyrifos, pyrethroids, and avermectins) and ASD. We also discusse future epidemiological and toxicological research directions on the relationship between pesticides and ASD.

Sporoderm-broken spores of Ganoderma lucidum alleviates liver injury induced by DBP and BaP co-exposure in rat.

Dibutyl phthalate (DBP) and Benzo(a)pyrene (BaP) are ubiquitous contaminants in environment and foodstuffs, which increase the chance of their combined exposure to humans in daily life. However, the combined effects of DBP and BaP on liver and the underlying mechanisms are still unclear. In this study, we explored the combined effects of DBP and BaP on liver and the potential mechanisms in a rat model. We found that DBP and BaP co-exposure activated the MyD88/NF-κB pathway through increasing TLR4 acetylation (TLR4ac) level, leading to the imbalance of pro-inflammatory factors (CXCL-13, IL-6 and TNF-α) and anti-inflammatory factors (IL-10), ultimately resulting in liver tissue damage and functional changes. Sporoderm-broken spores of Ganoderma lucidum (SSGL) had strong alleviating effects on liver injury induced by DBP and BaP co-exposure. Our study found that SSGL suppressed TLR4ac-regulated MyD88/NF-κB signaling to reduce the release of pro-inflammatory factors, and promote the secretion of IL-10, thus alleviating liver injury caused by DBP and BaP co-exposure. In conclusion, SSGL contributed to liver protection against DBP and BaP-induced liver injury in rats via suppressing the TLR4ac-regulated MyD88/NF-κB signaling.

miR-122-5p regulates hepatocytes damage caused by BaP and DBP co-exposure through SOCS1/STAT3 signaling in vitro.

BaP and DBP are ubiquitously and contemporaneously present in the environment. However, Current studies largely concentrate on the effects of a single pollutant (BaP or DBP). The liver is vital for biogenic activities. The effects of BaP and DBP co-exposure on liver remain unclear. Thus, we treated human normal liver cell (L02 cell) with BaP or/and DBP. We found that compared to individual exposure, co-exposure to BaP and DBP induced further increased levels of AST and ALT. BaP and DBP co-exposure caused further increased levels of IL-2, IL-6, and TNF-α, decreased IL-10 level, and a higher percentage of apoptotic cells and S-phase arrest cells. BaP and DBP co-exposure worsen the decrease of miR-122-5p level and chaos of SOCS1/STAT3 signaling. Dual-luciferase reporter gene assays showed that SOCS1 was a validated target of miR-122-5p. miR-122-5p overexpression alleviated the increased SOCS1 expression, decreased phospho-STAT3 expression, decreased IL-10 level, increased TNF-α levels, increased percentage of apoptosis and S-phase arrest, and cytotoxicity induced by BaP and DBP co-exposure in hepatocytes. These results suggested that miR-122-5p negatively regulated the synergistic effects on apoptosis and disorder of inflammatory factor secretion involved in hepatocyte injury caused by BaP and DBP co-exposure through targeting SOCS1/STAT3 signaling.

The role of H3K9me2-regulated base excision repair genes in the repair of DNA damage induced by arsenic in HaCaT cells and the effects of Ginkgo biloba extract intervention.

Arsenic is an established human carcinogen that can induce DNA damage; however, the precise mechanism remains unknown. Histone modification is of great significance in chemical toxicity and carcinogenesis. To investigate the role of histone H3K9me2 in arsenic-induced DNA damage, HaCaT cells were exposed to sodium arsenite in this study, and the results showed that the enrichment level of H3K9me2 at the N-methylated purine-DNA-glycosylase (MPG), X-ray repair cross-complementary gene 1 (XRCC1), and polyadenylate diphosphate ribose polymerase-1 (PARP1) promoter regions of base-excision repair (BER) genes was increased, which inhibited the expression of these BER genes, thereby inhibiting the repair of DNA damage and aggravating the DNA damage. Furthermore, the molecular mechanism by which H3K9me2 participates in the BER repair of arsenic-induced DNA damage was verified based on functional loss and gain experiments. In addition, Ginkgo biloba extract can upregulate the expression of MPG, XRCC1, and PARP1 and ameliorate cell DNA damage by reducing the enrichment of H3K9me2 at repair gene promoter regions.

Histone demethylase JHDM2A regulates H3K9 dimethylation in response to arsenic-induced DNA damage and repair in normal human liver cells.

Long-term arsenic exposure is a worldwide public health problem that causes serious harm to human health. The liver is the main target organ of arsenic toxicity; arsenic induces disruption of the DNA damage repair pathway, but its mechanisms remain unclear. In recent years, studies have found that epigenetic mechanisms play an important role in arsenic-induced lesions. In this study, we conducted experiments in vitro using normal human liver cells (L-02) to explore the mechanism by which the histone demethylase JHDM2A regulates H3K9 dimethylation (me2) in response to arsenic-induced DNA damage. Our results indicated that arsenic exposure upregulated the expression of JHDM2A, downregulated global H3K9me2 modification levels, increased the H3K9me2 levels at the promoters of base excision repair (BER) genes (N-methylpurine-DNA glycosylase [MPG], XRCC1 and poly(ADP-ribose)polymerase 1) and inhibited their expression levels, causing DNA damage in cells. In addition, we studied the effects of overexpression and inhibition of JHDM2A and found that JHDM2A can participate in the molecular mechanism of arsenic-induced DNA damage via the BER pathway, which may not be involved in the BER process because H3K9me2 levels at the promoter region of the BER genes were unchanged following JHDM2A interference. These results suggest a potential mechanism by which JHDM2A can regulate the MPG and XRCC1 genes in the process of responding to DNA damage induced by arsenic exposure and can participate in the process of DNA damage repair, which provides a scientific basis for understanding the epigenetic mechanisms and treatments for endemic arsenic poisoning.

Modulation of optical transmittance and conductivity by the period, linewidth and height of Au square mesh electrodes.

Metal transparent conductive electrode (TCE) with surface plasmons has been extensively studied for light absorption enhancement in solar cells and light extraction in Light-Emitting Diodes etc. But its transparent conductive properties and surface plasmons are controlled by its micromorphologies and microstructures. In this work, photoelectric coupling effects and optical transmittance modulations of period, linewidth and height of Au nanowire in square mesh electrode were investigated detailedly using a comprehensive finite-difference time domain calculation stimulation, and then Au square mesh TCEs with the 500 nm in period, 70 nm in height and linewidth ranging from 60 to 100 nm were fabricated using electron beam lithography. The measured results showed that the optical transmittance of the TCEs is about 70% in the 350-700 nm wavelength range and over 80% in the 700-1000 nm range, which accord with the theoretical simulation results. Optical transmittance is affected by reflection loss, localized surface plasmon resonances and surface plasmon polarizations (SPPs) absorption loss, concerned about geometry parameters. SPPs dip peak position exhibits a blue-shift from 844 to 812 nm and the width of peak increases with increasing the linewidth from 60 to 100 nm, The measured surface resistivity of the TCEs with the 500 nm in period, 50 nm in height and 50 nm in linewidth is about 74.5 Ω/m(2), about two times bigger than that of commercial indium tin oxide glass.

Fuzzy Adaptive Finite-Time Resilient Control Against Unknown False Data Injection Attacks for MIMO Nonlinear Switched Systems With Unknown Dead Zone.

This article studies the finite-time adaptive resilient control problem for MIMO nonlinear switched systems with the unknown dead zone. The sensors of the controlled systems suffer from unknown false data injection (FDI) attacks so that all states cannot be directly applied to the design process of the controller. To address this negative impact of FDI attacks, a new coordinate transformation is designed in control design. Moreover, the Nussbaum gain technique is introduced to deal with the difficulty of unknown time-varying weights caused by FDI attacks. Based on the common Lyapunov function method, a finite-time resilient control algorithm is designed by employing compromised state variables, which ensures that all signals of the closed-loop systems are bounded under arbitrary switching rules even in the presence of unknown FDI attacks. Compared with the existing results, the proposed control algorithm not only enables the controlled systems to reach an equilibrium state in a finite time but also removes the assumption that the sign of the attack weights is positive. In the end, a practical simulation example proves that the designed control method is valid.

Distributed State Estimation for Linear Systems in Networks With Antagonistic Interactions.

This article deals with the distributed state estimation problem for linear systems in networks with cooperative interactions and antagonistic interactions, where the cooperative interactions and the antagonistic interactions are characterized by the positive weights and the negative weights, respectively. Due to the coexistence of the cooperative interactions and the antagonistic interactions, the existing methods based on the non-negatively weighted graph become not applicable. First, a partition method of the nodes and a decomposition form of the system matrices are introduced. Then a new form of distributed observers is proposed in the network with cooperative interactions and antagonistic interactions. Necessary and sufficient conditions, which guarantee the existence of proposed distributed observers, are presented. In particular, when the communication network is cooperative, the proposed method is suitable for two cases, that is, the nodes in each independent strongly connected component are jointly detectable, or each node is jointly detectable with its neighbors. Finally, three examples are simulated to illustrate the effectiveness of the proposed methods.

Restraint of Nonradiative Recombination via Modulation of n-Phase Distribution through Interfacial Lithium Salt Insertion for High-Performance Pure-Blue Perovskite LEDs.

Quasi-two-dimensional perovskite has been widely used in blue perovskite light-emitting diodes. However, the performance of these devices is still hampered by random phase distribution, nonradiative recombination, and imbalanced carrier transport. In this work, an effective strategy is proposed to mitigate these limitations by inserting lithium salts at the interfaces between the hole transport layer (HTL) and the perovskite layer. The perovskite film on the inserted Li2CO3 layer exhibits reasonable n-value redistribution, which leads to the repressive nonradiation recombination and enhanced carrier transport. Moreover, the inserted Li2CO3 layer also improves the electrical conductivity of PEDOT:PSS and hinders indium ion diffusion from the PEDOT:PSS layer to the perovskite film, which inhibits exciton quenching and nonradiative recombination loss at the HTL/perovskite interface. Taking advantage of these merits, we have successfully fabricated efficient pure-blue PeLEDs with an external quantum efficiency of 6.2% at 472 nm and a luminance of 726 cd cm-2. The restraint of nonradiative recombination at the interface offers a promising approach for efficient pure-blue PeLEDs.

Secure State Estimation of Nonlinear Cyber-Physical Systems Against DoS Attacks: A Multiobserver Approach.

This article focuses on the problem of secure state estimation for cyber-physical systems (CPSs), whose physical plants are modeled as nonlinear strict-feedback systems. The measured output is sent to the designed observer over a wireless communication network subject to denial-of-service (DoS) attacks. Due to the energy constraints of the attackers, the attack duration is upper bounded. Under DoS attacks, the transmission is prevented, which worsens the estimation accuracy of the existing nonlinear observers significantly. To maintain the estimation performance, a novel multiobserver scheme and a switched algorithm are proposed by introducing the hold-input mechanism and the cascade observer technique. In comparison to the existing results, where the estimation error systems may be unstable during the attack time interval, the estimation error of the designed observer converges exponentially, such that the estimation performance is improved effectively. Finally, the theoretical findings are illustrated by simulation results.

Optimal Stealthy Attacks With Energy Constraint Against Remote State Estimation.

This article investigates the problem of energy-constrained stealthy attack strategy against remote state estimation for cyber-physical systems. Taking into account the energy constraint, the malicious attacker is required to schedule the off-line generated signals to modify the transmitted data with limited times over a finite-time horizon under the stealthiness condition, which makes the design of attack strategy more complex. Different from the attack schedules which are studied on the basis of prescribed attack signals in the existing results, the attack strategy is presented under the framework of collaborative design to deteriorate the estimation performance to the largest extent, which yet leads to the coupling between the attack schedules and attack signals. To overcome the difficulty without sacrificing the optimality, the attack design problem is solved in two steps. First, analyze the problem with the given attack schedule to derive the optimal attack signals. Then, the optimal schedule is obtained by efficiently solving the nonlinear 0-1 programming problem based on the algorithm of reducing the search space which is designed to eliminate a part of the nonoptimal solutions. To demonstrate the theoretical results, a simulation example is provided.

Optimal energy constrained deception attacks in cyber-physical systems with multiple channels: A fusion attack approach.

This paper studies the issue of developing the optimal deception attacks on the multiple channels in cyber-physical systems, where the attackers are limited by energy constraints. To fully utilize the eavesdropped data, by linearly combining the innovations from the different channels, a fusion attack model is proposed under the stealthiness condition. According to the statistical characteristics of the correlated stochastic variables and the orthogonality principle, the state estimation error is quantified and analyzed by deriving the iteration of the error covariance matrices of the remote estimators under the proposed attack framework. Moreover, by analyzing the correlations of the decision variables in the objective function, it is shown that the attack parameters and energy allocation strategy can be derived by two steps without loss of optimality, such that the optimal attack scheme is acquired by solving a multivariate semi-definite programming (SDP) problem and a linear 0-1 programming problem respectively. Finally, simulation examples are provided to illustrate the effectiveness of the proposed method.