Search

Abstract Ferroelectrics are essential in memory devices for multi-bit storage and high-density integration. Ferroelectricity mainly exists in compounds but rare in single-element materials due to their lack of spontaneous polarization in the latter. However, we report a room-temperature ferroelectricity in quasi-one-dimensional Te nanowires. Piezoelectric characteristics, ferroelectric loops and domain reversals are clearly observed. We attribute the ferroelectricity to the ion displacement created by the interlayer interaction between lone-pair electrons. Ferroelectric polarization can induce a strong field effect on the transport along the Te chain, giving rise to a self-gated ferroelectric field-effect transistor. By utilizing ferroelectric Te nanowire as channel, the device exhibits high mobility (~220 cm2·V−1·s−1), continuous-variable resistive states can be observed with long-term retention (>105 s), fast speed (1.92 TB/cm2). Our work provides opportunities for single-element ferroelectrics and advances practical applications such as ultrahigh-density data storage and computing-in-memory devices.

Objective: Previous studies have shown that apolipoprotein E (ApoE) gene polymorphisms have an impact on coronary artery disease(CAD). However, many studies have small sample sizes and different conclusions. The purpose was to retrospectively study the influence of ApoE gene polymorphisms on CAD. Methods: This study assessed the influence of different ApoE genotypes on coronary heart disease in patients who received coronary angiography and used multivariate logistic regression to assess the influence of different ApoE genotypes on CAD. Results: Patients with different ApoE genotypes had no obvious differences in the incidence of hypertension, diabetes or obesity（P > 0.05). Patients with ε2/ε2 had higher incidence of hypertriglyceridemia than patients with other ApoE genotypes, while patients with ε3/ε3 had a lower incidence of hypertriglyceridemia than those with ε3/ε4,ε4/ε4, ε2/ε3 and ε2/ε2（P 0.05). ε2/ε4 and ε2/ε3 reduced the risk of high LDL-C, and reduced the severity and incidence of coronary heart（P

Abstract Background Healthy lifestyles are crucial for preventing chronic diseases. Nonetheless, approximately 90% of Chinese community residents regularly engage in at least one unhealthy lifestyle. Mobile smart devices-based health interventions (mHealth) that incorporate theoretical frameworks regarding behavioral change in interaction with the environment may provide an appealing and cost-effective approach for promoting sustainable adaptations of healthier lifestyles. We designed a randomized controlled trial (RCT) to evaluate the effectiveness of a socioecological model-guided, smart device-based, and self-management-oriented lifestyles (3SLIFE) intervention, to promote healthy lifestyles among Chinese community residents. Methods This two-arm, parallel, cluster-RCT with a 6-month intervention and 6-month follow-up period foresees to randomize a total of 20 communities/villages from 4 townships in a 1:1 ratio to either intervention or control. Within these communities, a total of at least 256 community residents will be enrolled. The experimental group will receive a multi-level intervention based on the socioecological model supplemented with a multi-dimensional empowerment approach. The control group will receive information only. The primary outcome is the reduction of modifiable unhealthy lifestyles at six months, including smoking, excess alcohol consumption, physical inactivity, unbalanced diet, and overweight/obesity. A reduction by one unhealthy behavior measured with the Healthy Lifestyle Index Score (HLIS) will be considered favorable. Secondary outcomes include reduction of specific unhealthy lifestyles at 3 months, 9 months, and 12 months, and mental health outcomes such as depression measured with PHQ-9, social outcomes such as social support measured with the modified Multidimensional Scale of Perceived Social Support, clinical outcomes such as obesity, and biomedical outcomes such as the development of gut microbiota. Data will be analyzed with mixed effects generalized linear models with family and link function determined by outcome distribution and accounting for clustering of participants in communities. Discussion This study will provide evidence concerning the effect of a mHealth intervention that incorporates a behavioral change theoretical framework on cultivating and maintaining healthy lifestyles in community residents. The study will provide insights into research on and application of similar mHealth intervention strategies to promote healthy lifestyles in community populations and settings. Trial registration number ChiCTR2300070575. Date of registration: April 17, 2023. https://www.chictr.org.cn/index.aspx .

A van der Waals (vdW) heterostructure is formed by combining multiple materials through vdW bonds. It can combine the advantages of electronic, optical, thermal, and magnetic properties of different 2D materials and has the potential to develop into the next generation of high‐performance functional devices. Herein, the current research advances of vdW heterostructures are reviewed. First, current fabrication methods and physical structures of vdW heterostructures are summarized. The 2D/nD (n = 0,1,2,3) mixed‐dimensional heterostructures are discussed in detail. Second, a new type of vdW heterostructure is introduced based on two‐dimensional electron gas with a nanoscale junction interface. Finally, the application prospects of vdW heterostructures in photoelectric and memory devices are further outlined by combing new applications in the neural networks. This review shows that vdW heterostructures have great advantages in high integration, energy harvesting, and logical operations, and it provides directions and suggestions for the future research and application of environmentally friendly, high‐performance, and smart functional devices.

The mechanical properties, electronic structure, electric transport and optoelectronic properties of a recently predicted wide bandgap semiconductor β-HfNCl monolayer are systematically studied by means of first-principles calculations. β-HfNCl monolayer is isotropic in mechanical properties, whose calculated Young’s modulus, shear modulus, and layer modulus of β-HfNCl monolayer are 128.9–129.2, 44.28, and 119.46 N m−1, respectively. An appropriate tensile strain (i.e., beyond 3 %) can induce a transition from indirect bandgap to direct bandgap. In addition, we construct several conceptual nanodevice structures based on β-HfNCl monolayer, such as pn-junction diodes, pin-junction field-effect transistors (FETs) and phototransistors. The electronic transport results reveal that the pn-junction diodes have obvious rectification effect and strong electric anisotropy. Their rectification ratios and electric anisotropy ratio (η) can reach up to 106 and 3.69, respectively. The FETs have an obvious field-effect behavior with a slightly lower rectification ratio (105). Moreover, we investigate the photoelectric response of the phototransistors of β-HfNCl monolayer under the illumination of light. They have a strong response to the light whose energy is larger than the violet light, indicating that the β-HfNCl monolayer can be a platform to detect the ultraviolet light. These findings provide crucial insights into the potential applications of β-HfNCl monolayer in electronic and optoelectronic devices.

Background Anthocyanin plays a protective role in cardiovascular disease through antioxidant effect. Whether anthocyanin can reduce salt-induced hypertension and the related mechanisms remain unclear. Methods Chronic infusion of vehicle (artificial cerebrospinal fluid, aCSF, 0.4 μL/h) or anthocyanin (10 mg/kg, 0.4 μL/h) into bilateral paraventricular nucleus (PVN) of Sprague-Dawley rats was performed. Then, the rats were fed a high salt diet (8% NaCl, HS) or normal salt diet (0.9%, NaCl, NS) for 4 weeks. Results High salt diet induced an increase in blood pressure and peripheral sympathetic nerve activity (increased LF/HF and decreased SDNN and RMSSD), which was accompanied by increased reactive oxygen species (ROS) production and angiotensin II type-1 receptor (AT1R) expression and function in the PVN. Moreover, the NOD-like receptor protein 3 (NLRP3) and related inflammatory proteins (caspase-1) expression, the pro-inflammatory cytokine levels including IL-1β and TNF-α were higher in PVN of rats with a high salt diet. Bilateral PVN infusion of anthocyanin attenuated NLRP3-dependent inflammation (NLRP3, caspase-1, IL-1β and TNF-α) and ROS production, reduced AT1R expression and function in PVN and lowered peripheral sympathetic nerve activity and blood pressure in rats with salt-induced hypertension. Conclusions Excessive salt intake activates NLRP3-dependent inflammation and oxidative stress and increased AT1R expression and function in the PVN. Bilateral PVN infusion of anthocyanin lowers peripheral sympathetic nerve activity and blood pressure in rats with salt-induced hypertension by improvement of expression and function of AT1R in the PVN through inhibiting NLRP3 related inflammatory and oxidative stress.

Amorphous alloys or metallic glasses (MGs) thin films have attracted extensive attention in various fields due to their unique functional properties. Here, we use in situ heating transmission electron microscopy (TEM) to investigate the thermal stability and crystallization behavior of Pd-Au-Si thin films prepared by a pulsed laser deposition (PLD) method. Upon heating treatment inside a TEM, we trace the structural changes in the Pd-Au-Si thin films through directly recording high-resolution images and diffraction patterns at different temperatures. TEM observations reveal that the Pd-Au-Si thin films started to nucleate with small crystalline embryos uniformly distributed in the glassy matrix upon approaching the glass transition temperature Tg=625K, and subsequently, the growth of crystalline nuclei into sub-10 nm Pd-Si nanocrystals commenced. Upon further increasing the temperature to 673K, the thin films transformed to micro-sized patches of stacking-faulty lamellae that further crystallized into Pd9Si2 and Pd3Si intermetallic compounds. Interestingly, with prolonged thermal heating at elevated temperatures, the Pd9Si2 transformed to Pd3Si. Simultaneously, the solute Au atoms initially dissolved in glassy alloys and eventually precipitated out of the Pd9Si2 and Pd3Si intermetallics, forming nearly spherical Au nanocrystals. Our TEM results reveal the unique thermal stability and crystallization processes of the PLD-prepared Pd-Au-Si thin films as well as demonstrate a possibility of producing a large quantity of pure nanocrystals out of amorphous solids for various applications.

Chryseobacterium indologenes is one of the primary causative agents of root rot of Panax notoginseng, which significantly affected plant growth and caused economic losses. With the increasing incidence of antibiotic-resistant bacterial phytopathogens, phage therapy has been garnered renewed attention in treating pathogenic bacteria. However, the therapeutic potential of phage therapy on root rot of P. notoginseng has not been evaluated. In this study, we isolated a novel lytic phage MA9V-1 infecting C. indologenes MA9 from sewage and monitored the formation of clear and round plaques with a diameter of approximately 0.5–1.5 mm. Phage MA9V-1 exhibited rapid absorption (>75% in 8 min), a latency period of 20 min, and a burst size of 10 particles per cell. Transmission electron microscopy indicated that the phage MA9V-1 is a new myovirus hosting C. indologenes MA9. Sequencing of phage genomes revealed that phage MA9V-1 contained a linear double-stranded DNA genome of 213,507 bp with 263 predicted open reading frames, including phage structure, host lysing, and DNA polymerase/helicase but no genes of tRNA, virulence, and antibiotic resistance. Our proteomic tree and genomic analysis revealed that phage MA9V-1 shares identity with Sphingomonas phage PAU and Tenacibaculum phage PTm1; however, they also showed apparent differences. Further systemic evaluation using phage therapy experiments on P. notoginseng suggested that phage MA9V-1 can be a potential candidate for effectively controlling C. indologenes MA9 infection. Thus, we have presented a novel approach to solving root rot in P. notoginseng.

Abstract Two-dimensional (2D) magnetic materials are essential for the development of the next-generation spintronic technologies. Recently, layered van der Waals (vdW) compound MnBi2Te4 (MBT) has attracted great interest, and its 2D structure has been reported to host coexisting magnetism and topology. Here, we design several conceptual nanodevices based on MBT monolayer (MBT-ML) and reveal their spin-dependent transport properties by means of the first-principles calculations. The pn-junction diodes and sub-3-nm pin-junction field-effect transistors (FETs) show a strong rectifying effect and a spin filtering effect, with an ideality factor n close to 1 even at a reasonably high temperature. In addition, the pip- and nin-junction FETs give an interesting negative differential resistive (NDR) effect. The gate voltages can tune currents through these FETs in a large range. Furthermore, the MBT-ML has a strong response to light. Our results uncover the multifunctional nature of MBT-ML, pave the road for its applications in diverse next-generation semiconductor spin electric devices.

Abstract With the rapid development of data‐driven human interaction, advanced data‐storage technologies with lower power consumption, larger storage capacity, faster switching speed, and higher integration density have become the goals of future memory electronics. Nevertheless, the physical limitations of conventional Si‐based binary storage systems lag far behind the ultrahigh‐density requirements of post‐Moore information storage. In this regard, the pursuit of alternatives and/or supplements to the existing storage technology has come to the forefront. Recently, organic‐based resistive memory materials have emerged as promising candidates for next‐generation information storage applications, which provide new possibilities of realizing high‐performance organic electronics. Herein, the memory device structure, switching types, mechanisms, and recent advances in organic resistive memory materials are reviewed. In particular, their potential of fulfilling multilevel storage is summarized. Besides, the present challenges and future prospects confronted by organic resistive memory materials and devices are discussed.

Summary: Based on density functional theory calculations, we elucidated the tunability of the atomic structures and magnetic interactions of Co/Pt3 interface (one layer of hcp(0001) Co and three layers of fcc(111) Pt) and thus the skyrmion sizes using strain. The dispersion relations of the spin spiral in the opposite directions, E(q) and E(-q), were evaluated based on generalized Bloch equations. Effective exchange coupling (EC) and Dzyaloshinsky-Moriya interaction (DMI) parameters between different neighbors Ji and di at different lattice constants were derived by fitting the resulting spin spiral dispersion E(q) to EC model with DMI and E(q)-E(-q) formula, respectively. We observed an increase in DMI and a significant decrease in EC with an increase in strain. Hence, the size of Néel-type skyrmions determined by the ratio of EC/DMI can be controlled by applying strain, leading to an effective approach to tailor the formation of skyrmion lattices by inducing slight structural modifications on the magnetic thin films.

Organic–inorganic hybrid perovskites (OHPs) with a rich reservoir of distinct physical attributes have been considered as promising resistive switching materials for next‐generation electronic devices, including resistive random‐access memory (RRAM) devices, artificial synapses, and logic operation. In this review, we first briefly introduce the structural and photoelectronic properties of OHPs materials, followed by elaborating the typical lateral/vertical device architectures and commonly‐used device fabrication technologies. Secondly, recent progress of OHPs in three categories of RRAM, artificial synapses, and logic operation, including various materials design, outstanding electrical behaviors, and multifunctional applications, are well discussed. Besides, the operational mechanisms and performance improvement strategies are summarized in a recapitulative way. Finally, current challenges and future development prospects of OHPs‐based devices are demonstrated to provide a better guideline for the next‐generation technical revolution. This review offers an encouraging recognition that OHPs hold immense expectation to keep up with the upcoming big‐data and artificial intelligence era.

The doping of impurity ions into perovskite lattices has been scrupulously developed as a promising method to stabilize the crystallographic structure and modulate the optoelectronic properties. However, the photoluminescence (PL) of Fe2+-doped mixed halide perovskite NCs is still relatively unexplored. In this work, the Fe2+-doped CsPb(ClxBr1−x)3 nanocrystals (NCs) are prepared by a hot injection method. In addition, their optical absorption, photoluminescence (PL), PL lifetimes, and photostabilities are compared with those of undoped CsPb(Br1−xClx)3 NCs. We find the Fe2+ doping results in the redshift of the absorption edge and PL. Moreover, the full width at half maximums (FWHMs) are decreased, PL quantum yields (QYs) are improved, and PL lifetimes are extended, suggesting the defect density is reduced by the Fe2+ doping. Moreover, the photostability is significantly improved after the Fe2+ doping. Therefore, this work reveals that Fe2+ doping is a very promising approach to modulate the optical properties of mixed halide perovskite NCs.

Background: Whether all types of inhaled corticosteroids (ICSs) would increase the pneumonia risk in patients with chronic obstructive pulmonary disease (COPD) remains controversial. We aimed to assess the association between ICSs treatment and pneumonia risk in COPD patients, and the impact of medication details and baseline characteristics of patients on the association.Methods: Four databases (PubMed, Embase, Cochrane Library, and Clinical Trials.gov) were searched to identify eligible randomized controlled trials (RCTs) comparing ICSs treatment with non-ICSs treatment on the pneumonia risk in COPD patients. Pooled results were calculated using Peto odds ratios (Peto ORs) with corresponding 95% confidence intervals (CIs).Results: A total of 59 RCTs enrolling 103,477 patients were analyzed. All types of ICSs significantly increased the pneumonia risk (Peto OR, 1.43; 95% CI, 1.34–1.53). Subgroup analysis showed that there was a dose-response relationship between ICSs treatment and pneumonia risk (low-dose: Peto OR, 1.33; 95% CI, 1.22–1.45; medium-dose: Peto OR, 1.50; 95% CI, 1.28–1.76; and high-dose: Peto OR, 1.64; 95% CI, 1.45–1.85). Subgroup analyses based on treatment durations and baseline characteristics (severity, age, and body mass index) of patients were consistant with the above results. Subgroup analysis based on severity of pneumonia showed that fluticasone (Peto OR, 1.75; 95% CI, 1.44–2.14) increased the risk of serious pneumonia, while budesonide and beclomethasone did not.Conclusions: ICSs treatment significantly increased the risk of pneumonia in COPD patients. There was a dose-response relationship between ICSs treatment and pneumonia risk. The pneumonia risk was related with COPD severity.

Co(II) mononuclear complex with different coordination geometry would display various of field-induced single-ion magnet (SIM) behaviors. Here, we identify a field-induced single-ion magnet in a mononuclear complex Co(H2DPA)2·H2O (H2DPA = 2,6-pyridine-dicarboxylic acid) by the hydrothermal method. The long axial Co-O coordination bond (Co1‧‧‧O3) can be formed by Co1 and O3. Therefore, Co(II) ion is six-coordinated in a distorted elongated octahedron. AC magnetization susceptibilities show that the effective energy barrier is up to 43.28 K. This is much larger than most mononuclear Co(II). The distorted elongated octahedron caused by the axial Co-O coordination bond is responsible for the high effective energy barrier. The distribution of electron density in Co1 and O3 atoms in the long axial bond would influence the magnetic relaxation process in turn. Our work deepens the relationship between the effective energy barrier and the weak change of ligand field by long axial bonds, which would facilitate constructing SIM with high energy temperature.

Ferroelectric with quantum-mechanical tunnel allows non-volatile resistance states and fast readout of the tunnel current in the ferroelectric tunnel junctions (FTJs) through the influence of ferroic orders. However, the complex interfacial effect between electrodes and traditional ferroelectric films has still remained to be solved. When 2D ferroelectrics are used in FTJs, the lattice-matched constraint and intermixing of cations between ferroelectric and substrate electrode can be avoid. Here we show various FTJs with low energy consuming, and high endurance made from 2D ferroelectric ReS _2 and different electrodes such as Pt/ReS _2 /Au, W/ReS _2 /SiO _2 /Si and W/ReS _2 /Nb:STO. With the help of in situ atomic force microscopy and piezoresponse force microscopy, we show that the memory can be manipulated in less than 1 μ m ^2 and the resistance switching should be caused by the ferroelectric polarization direction in the distorted ReS _2 . Then, we demonstrate that the memory devices can be easily transferred to a polyimide or flexible SiO _2 /Si substrate. These FTJs shows good bending stability, illustrating their potential applications in flexible electronics. Considering the weak Van der Waals interfacial bonding between 2D ferroelectric and electrode, the polarization-dependent Schottky emission and interface-limited Fowler–Nordheim tunnel current play the key role in resistance switching respectively. Our work provides a simple way to construct various building blocks for circuits in harsh electronics with low energy consuming, good bending stability and high-density data storage.

In this work, Ca _3 Ti _2 O _7- _x F _x thin films on (110) SrTiO _3 substrates were prepared by two steps as deposited via pulsed laser deposition and fluorinated with polyvinylidene fluoride. Despite the unchanged crystal structure of the fluorinated films, the changed valence state can be used to confirm the incorporation of F ^−1 and the weakened chemical bond of Ca–O. Furthermore, we found that the photoelectric switch can be observed at a wide range of light wavelength from 405 nm to 808 nm. It is found that the photosensitivity of 4 × 10 ^4 (405 nm) in the fluorine has been increased by two orders of magnitude, which is most likely due to the deep energy levels in the reduced band gap of 2.3 eV. This work paves the way for the enhanced photoconductive devices via the anionic defect engineering.

The atomic and electronic structures have been investigated for the multiferroic behavior in the perovskite oxides, which also can be tuned by oxygen vacancy for enhancing properties. Here epitaxial Sr(Ti _0.875 Fe _0.125 )O _3- _δ thin films were deposited on (001) SrTiO _3 substrates by pulsed laser deposition and were post-annealed in an oxygen atmosphere. We found that the oxygen vacancies formed in high vacuum are the source of the macroscopic crystal distortion as the growth strain along out-of-plane . Moreover, it was determined that the full-filled Fe 3 d states induced by oxygen vacancy effect are responsible for the decreased magnetization. This work demonstrates that the oxygen vacancy can both lead to atomic and electronic reconstructions in the perovskite films for manipulating ferroic properties.

The electronic structures and optical properties of Boron, Carbon or Nitrogen doped BaTiO3 are calculated by the first-principles calculations. The doped atoms decrease the band gap of BaTiO3 significantly, which could increase the host material ability to absorb the visible light. The absorption spectrum calculations confirm that both Boron and Carbon-doped BaTiO3 have a favorable performance in the absorption of visible light. However, Nitrogen-doped BaTiO3 doesn’t present the improvement. BaTiO3 doped with Boron or Carbon is expected to be a new class of perovskite materials for the field of solar energy.