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Identifying the oxidation structure of two-dimensional interfaces is crucial to improve surface chemistry and electronic properties. Beyond graphene with only phenyl rings, a novel carbon-nitrogen material, C3N, presents an intrinsic heterogeneous surface morphology where each phenyl ring is encircled by six nitrogen atoms, yet its atomistic oxidation structure remains unclear. Here, combining a series of density functional theory calculations and ab initio molecular dynamics simulations, we demonstrate that thermodynamically favorable oxidation loci are confined to the phenyl ring, and kinetic transformations of oxidation structures are feasible along the phenyl ring, whereas those toward nitrogen atoms are proven to be extremely difficult. These results are attributed to the lower barrier of oxygen atom migration along the phenyl ring, while the significantly high barriers toward nitrogen atoms are due to the heterogeneous potential energy surface for oxygen–C3N interaction. This work highlights the significance of surface morphology on the characteristics of oxidation structure, offering insights into tunable electronic properties via confined interfacial oxidation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pristine C 3 N monolayer shows stronger O 2 physisorption than pristine graphene. • The most preferable O 2 dissociation is an indirect two-step path with chemisorbed O 2. • Two dangling C-O bonds on the para-carbon site is the most stable oxidized structure. • Pristine C 3 N monolayer is more susceptible to oxidation than pristine graphene. • Electronic properties can be altered significantly due to the presence of two chemisorbed O atoms. The oxygen dissociation and the oxidized structure on the pristine C 3 N monolayer in exposure to air are the inevitably critical issues for the C 3 N engineering and surface functionalization yet have not been revealed in detail. Using the first-principles calculations, we have systematically investigated the possible O 2 adsorption sites, various O 2 dissociation pathways and the oxidized structures. It is demonstrated that the pristine C 3 N monolayer shows more O 2 physisorption sites and exhibits stronger O 2 adsorption than the pristine graphene. Among various dissociation pathways, the most preferable one is a two-step process involving an intermediate state with the chemisorbed O 2 and the barrier is lower than that on the pristine graphene, indicating that the pristine C 3 N monolayer is more susceptible to oxidation than the pristine graphene. Furthermore, we found that the most stable oxidized structure is not produced by the most preferable dissociation pathway but generated from a direct dissociation process. These results can be generalized into a wide range of temperatures and pressures using ab initio atomistic thermodynamics. Our findings deepen the understanding of the chemical stability of 2D crystalline carbon nitrides under ambient conditions, and could provide insights into the tailoring of the surface chemical structures via doping and oxidation. [ABSTRACT FROM AUTHOR]

In recent years, 2D layered materials have been considered as promising photon absorption channel media for next-generation phototransistors due to their atomic thickness, easily tailored single-crystal van der Waals heterostructures, ultrafast optoelectronic characteristics, and broadband photon absorption. However, the photosensitivity obtained from such devices, even under a large bias voltage, is still unsatisfactory until now. In this paper, high-sensitivity phototransistors based on WS2 and MoS2 are proposed, designed, and fabricated with gold nanoparticles (AuNPs) embedded in the gate dielectric. These AuNPs, located between the tunneling and blocking dielectric, are found to enable efficient electron trapping in order to strongly suppress dark current. Ultralow dark current (10−11 A), high photoresponsivity (1090 A W−1), and high detectivity (3.5 × 1011 Jones) are obtained for the WS2 devices under a low source/drain and a zero gate voltage at a wavelength of 520 nm. These results demonstrate that the floating-gate memory structure is an effective configuration to achieve high-performance 2D electronic/optoelectronic devices. [ABSTRACT FROM AUTHOR]

• Recent advances in Avalanche Photodiodes: unique capabilities and performance enhancements in recent years. • Avalanche process description theories in Avalanche Photodiodes guide infrared detector development directions. • Finely engineered device structures propel further enhancements in infrared detector performance. • Low-dimensional and Three-dimensional Materials Collaboration: Paving a Novel Pathway for Infrared Detectors. Currently, the development trend of infrared detection systems is oriented towards achieving smaller size, reduced weight, lower power consumption, decreased cost, and heightened performance, collectively referred to as SWAP3. In this context, a rapid evolution is witnessed in the realm of next-generation high-sensitivity infrared avalanche photodiodes (APD). In recent years, the increasing demands for detector performance from astronomical, remote sensing, and civilian applications have presented novel challenges for the mechanistic exploration and device design of traditional avalanche photodetectors. This review explores the forefront of infrared APD technology, focusing on the remarkable progress achieved through the utilization of II-VI and III-V semiconductor families and the exploration based on novel low-dimensional materials. The review provides a detailed analysis of the unique properties and performance enhancements exhibited by APDs based on these material systems, shedding light on their potential for revolutionizing infrared sensing and imaging applications, and inspiring further innovation and exploration in the field of infrared photodetection. [ABSTRACT FROM AUTHOR]

Background and Aims: Primary aldosteronism (PA) is an adrenal disorder of autonomous aldosterone secretion which promotes arterial injury. We aimed to explore whether PA is causally associated with lower-extremity arterial disease (LEAD). Methods: We included 39,713 patients with diabetes and 419,312 participants without diabetes from UK Biobank. We derived a polygenic risk score (PRS) for PA based on previous genome-wide association studies (GWAS). Outcomes included LEAD and LEAD related gangrene or amputation. We conducted a two-sample Mendelian randomization analysis for PA and outcomes to explore their potential causal relationship. Results: In whole population, individuals with a higher PA PRS had an increased risk of LEAD. Among patients with diabetes, compared to the subjects in the first tertile of PA PRS, subjects in the third tertile showed a 1.24-fold higher risk of LEAD (OR 1.24, 95% CI 1.03–1.49) and a 2.09-fold higher risk of gangrene (OR 2.09, 95% CI 1.27–3.44), and 1.72-fold higher risk of amputation (OR 1.72, 95% CI 1.10–2.67). Among subjects without diabetes, there was no significant association between PA PRS and LEAD, gangrene or amputation. Two-sample Mendelian randomization analysis indicated that genetically predictors of PA was significantly associated with higher risks of LEAD and gangrene (inverse variance weighted OR 1.20 [95% CI 1.08–1.34]) for LEAD, 1.48 [95% CI 1.28–1.70] for gangrene), with no evidence of significant heterogeneity or directional pleiotropy. Conclusions: Primary aldosteronism is genetically and causally associated with higher risks of LEAD and gangrene, especially among patients with diabetes. Targeting on the autonomous aldosterone secretion may prevent LEAD progression. [ABSTRACT FROM AUTHOR]

Background: Individuals in the workplace are exposed to various environments, tasks, and schedules. Previous studies have indicated a link between occupational exposures and an increased risk of chronic kidney disease (CKD). However, the social conditions of the work environment may also be a crucial contributing factor to CKD. Furthermore, individuals may encounter multiple occupational-related risk factors simultaneously, underscoring the importance of investigating the joint risk of different working conditions on CKD. Methods: A prospective analysis of 65,069 UK Biobank participants aged 40 to 69 years without CKD at baseline (2006–2010) was performed. A self-administered questionnaire assessed working conditions and a working conditions risk score were developed. Participants who answered "sometimes" or "often" exposure to occupational heat or occupational secondhand cigarette smoke; involved in shift work or heavy workloads ("usually" or "always"), were grouped as high-risk working conditions. Each working condition was scored as 1 if grouped as high-risk, and 0 if not. The working conditions risk score was equal to the sum of these four working conditions. Cox proportional hazard regression models were used to estimate the associations between working conditions and CKD incidence. Results: The mean follow-up time was 6.7 years. After adjusting for demographic, lifestyle, and working time factors, the hazard ratios for the development of CKD for heavy workloads, shift work, occupational secondhand cigarette smoke exposure, and occupational heat exposure were 1.24 (95%CI = 1.03, 1.51), 1.33 (95%CI = 1.10, 1.62), 1.13 (95%CI = 1.01, 1.26), 1.11 (95%CI = 0.99, 1.24), respectively. The risk of CKD was found to be significantly associated with an increasing working conditions risk score. Individuals with a working conditions risk score of 4 had an 88.0% (95% CI = 1.05, 3.35) higher risk of developing CKD when compared to those with a working conditions risk score of 0. Conclusions: Adverse working conditions, particularly when considered in combination, can significantly elevate the risk of chronic kidney disease (CKD). These results provide a reference for implementing measures to prevent CKD. [ABSTRACT FROM AUTHOR]

An efficient ferroelectric-enhanced side-gated single CdS nanowire (NW) ultraviolet (UV) photodetector at room temperature is demonstrated. With the ultrahigh electrostatic field from polarization of ferroelectric polymer, the depletion of the intrinsic carriers in the CdS NW channel is achieved, which significantly reduces the dark current and increases the sensitivity of the UV photodetector even after the gate voltage is removed. Meanwhile, the low frequency noise current power of the device reaches as low as 4.6 × 10−28 A2 at a source-drain voltage Vds = 1 V. The single CdS NW UV photodetector exhibits high photoconductive gain of 8.6 × 105, responsivity of 2.6 × 105 A W−1, and specific detectivity ( D*) of 2.3 × 1016 Jones at a low power density of 0.01 mW cm−2 for λ = 375 nm. In addition, the spatially resolved scanning photocurrent mapping across the device shows strong photocurrent signals near the metal contacts. This is promising for the design of a controllable, high-performance, and low power consumption ultraviolet photodetector. [ABSTRACT FROM AUTHOR]

The gastric bacterial pathogen Helicobacter pylori persistently colonizes the gastric mucosa of humans and plays a critical role in the development of gastritis, peptic ulceration and gastric adenocarcinoma. Consequently, the eradication of H. pylori might contribute to the prevention of H. pylori-associated gastric diseases. In this study, a multi-epitope vaccine CTB-UE (CUE) was displayed on the surface of non-genetically modified Lactococcus lactis particles (GEM) to enhance immunogenicity. This particulate vaccine CUE-GEM induced serum and mucosal specific antibody responses against native H. pylori urease and provided potent protection to eliminate H. pylori colonization and relieve gastritis in an H. pylori-infected BALB/c mouse model. The immuno-protective mechanisms are highly associated with CD4 Th cell-mediated and humoral immunity, especially local immunity. There might be two main aspects of this association. One aspect is related to the suppression of urease activity by promotion of the production of specific mucosal neutralizing antibody. The other aspect is correlated with alleviating gastritis by regulating the gastric pro-inflammatory cytokine profile, especially IFN-γ and IL-17. These results demonstrated that conjugating antigen vaccines with GEM particles could lead to promising oral therapeutic vaccine formulations against H. pylori infection. [ABSTRACT FROM AUTHOR]

Epidemiologic studies have provided solid evidence for the neurotoxic effect of lead for decades of years. In view of the fact that children are more vulnerable to the neurotoxicity of lead, lead exposure has been an urgent public health concern. The modes of action of lead neurotoxic effects include disturbance of neurotransmitter storage and release, damage of mitochondria, as well as induction of apoptosis in neurons, cerebrovascular endothelial cells, astroglia and oligodendroglia. Our studies here, from a novel point of view, demonstrates that lead specifically caused induction of COX-2, a well known inflammatory mediator in neurons and glia cells. Furthermore, we revealed that COX-2 was induced by lead in a transcription-dependent manner, which relayed on transcription factor NFAT, rather than AP-1 and NFκB, in glial cells. Considering the important functions of COX-2 in mediation of inflammation reaction and oxidative stress, our studies here provide a mechanistic insight into the understanding of lead-associated inflammatory neurotoxicity effect via activation of pro-inflammatory NFAT3/COX-2 axis. [ABSTRACT FROM AUTHOR]

Correlated vanadium dioxide (VO2) has shown promises in functional materials and advanced electronic devices with outstanding metal–insulator transition (MIT). The manipulations of MIT and structural phase transition in correlated oxides are among the major challenges in both fundamental science and technological applications. Herein, the modulation of MIT behaviors in one VO2 nanowire with an artificial oxidized domain induced by selected‐area chemical nanoengineering is described. The formation of an artificial oxidized domain enables to suppress MIT and stabilize the insulating phase above the MIT temperature of pristine VO2 nanowires, which leads to an enhanced MIT hysteresis and temperature. The creation of artificial domains and the modulation of MIT in correlated oxide nanowires help to both investigate the essential physics behind correlated nanomaterials and fabricate nanoscale multifunctional devices. [ABSTRACT FROM AUTHOR]