Perylene-based molecular device: multifunctional spintronic and spin caloritronic applications.

Carbon-based magnetic molecular junctions are promising candidates for nanoscale spintronic applications because they are atomically thin and possess high stability and peculiar magnetism. Herein, based on first-principles and non-equilibrium Green's function, we designed a carbon-based molecular spintronic device composed of carbon atomic chains, zigzag-edged graphene nanoribbon (ZGNR), and a perylene molecule. Our results show that the device exhibits integrated spintronic and spin caloritronic functionalities, such as the bias-voltage driven spin filtering effect, negative differential resistance effect and giant magnetoresistance, temperature-gradient driven spin Seebeck effect, thermal spin filtering effect, high thermal magnetoresistance, and thermal colossal giant magnetoresistance. Furthermore, considering the phonon vibration effect, the spin and charge thermoelectric figure of merits (ZTsp and ZTch) can be enhanced and the peak of ZTsp is much larger than that of ZTch, indicating the excellent thermospin performance. The asymmetrical contact configuration between the carbon atomic chain and perylene/ZGNR inhibits the phonon thermal conductivity significantly, leading to the optimal ZTsp and ZTch of 2.4 and 0.5 at 300 K, respectively. These results suggest multifunctional spintronic and spin caloritronic applications for the perylene-based molecular device.

lncRNA NBAT1 Inhibits Cell Metastasis and Promotes Apoptosis in Endometrial Cancer by Sponging miR-21-5p to Regulate PTEN.

Objective: Long noncoding RNA neuroblastoma-associated transcript 1 (NBAT1) is implicated in the progression of various cancers. Nevertheless, its biological function in endometrial cancer (EC) remains unknown. Methods: The levels of NBAT1, miR-21-5p, and PTEN in EC cells and EC tissues were examined by RT-qPCR. Western blot was carried out to assess the protein expression of PTEN. The dual-luciferase reporter assay was conducted to explore the interactions among NBAT1, miR-21-5p, and PTEN. The effect of NBAT1 on EC proliferation, metastasis, and apoptosis was evaluated by CCK-8, transwell assays, wound healing, and flow cytometry. miR-21-5p mimics or NBAT1+miR-21-5p were transfected into HEC-1A and Ishikawa cells to investigate whether NBAT1 regulated EC tumorigenesis via sponging miR-21-5p. Results: NBAT1 is downregulated, and miR-21-5p is upregulated in EC cells and tumor tissues. Overexpression of NBAT1 inhibits the proliferation, migration, and invasion abilities of EC cells and facilitated apoptosis. NBAT1 directly binds and negatively regulates miR-21-5p in EC. miR-21-5p mimics reverses the effect of lncRNA NBAT1 overexpression on the proliferation and migration of EC cells. PTEN is a downstream gene of miR-21-5p. lncRNA NBTA1 elevates PTEN expression via sponging miR-21-5p. Conclusions: lncRNA NBAT1 acts as a tumor suppressor in EC via regulating PTEN through sponging miR-21-5p.

Artificial Intelligence Algorithm-Based Computed Tomography Image in Assessment of Acute Renal Insufficiency of Patients Undergoing Percutaneous Coronary Intervention.

This study was aimed to analyze the changes in renal function of patients undergoing percutaneous coronary intervention (PCI) surgery and the characteristics of their computed tomography (CT) image based on artificial intelligence algorithms. In this study, 104 patients with coronary atherosclerotic heart disease (CAHD) were treated as the research objects. They were divided into an experimental group (patients who underwent CAG and PCI within 1 week after enhanced coronary CT (ECCT)) and the control group (patients who underwent CAG and PCI within 1-3 weeks after ECCT). Renal imaging scans of patients were performed by CT based on discrete inseparable shear transform (DNST) optimized algorithm, which was named as O-DNST. The results showed that the serum creatinine (Scr), blood urea nitrogen (BUN), and urine protein (UP) levels of patients in the experimental group were significantly higher than those of the control group 24-72 hours after surgery, while the levels of endogenous creatinine clearance (Ccr) and estimated glomerular filtration rate (eGFR) were significantly lower than those of the control group (P < 0.05). The levels of ß2 microglobulin (ß2-MG), C-reactive protein (CRP), interleukin 6 (IL-6), and tumor necrosis factor (TNF-α) in the experimental group were significantly higher than those in the control group 24-72 hours after surgery (P < 0.05). The incidence of contrast-induced nephropathy (CIN) in the experimental group (15.38%) was significantly higher than that in the control group (5.8%), and the difference was statistically significant (P < 0.05). The results showed that repeated application of contrast agent in a short period of time can promote the increase of serum inflammation levels in PCI patients, which may be a risk factor for CIN in PCI patients.

Physical mechanisms of photoinduced charge transfer in neutral and charged donor-acceptor systems.

In this paper, we provide visualization methods to reveal the physical mechanisms of photoinduced charge transfer in neutral and charged donor-acceptor systems. These visualization methods use the charge density difference and transition density matrix, which can promote deeper understanding of photoinduced charge transfer in donor-acceptor systems.

Optical Properties of Artemisinin and Its Derivatives.

Artemisinin and its derivatives are of great research value in biology. In this work, we study their chiral and optical properties. The multidimensional multifunction analysis method is used to analyze the linear and nonlinear optical processes (one-photon and two-photon absorption: OPA and TPA), electronic circular dichroism (ECD), and Raman optical activity (ROA) mechanisms under light excitation. Transition dipole moments (TDMs) and charge difference density (CDD) are used to describe the electromagnetic interaction between ECD and ROA when a substance is excited by light. The theoretical research results of the study show that the dioxygen atoms provide an intermediary for the transfer between charges and also enhance the role of the TDMs. This generalized chiral theory can not only explain the traditional sources of chirality but also distinguish whether the molecule has chirality when the chiral center is not obvious. By analyzing ROA and different vibration modes, we can clearly observe that each part of the molecule responds differently when excited.

Association between Psychological Factors and Condom Use with Regular and Nonregular Male Sexual Partners among Chinese MSM: A Quantitative Study Based on the Health Belief Model.

OBJECTIVE: The Chinese men who have sex with men (MSM) population is suffering from a high HIV infection rate owing to unprotected anal sex. The Health Belief Model (HBM) has been proven to be an effective frame associated with behavior maintenance. Based on HBM, we analyzed the beliefs associated with consistent condom use behavior with regular and nonregular partners among MSM to better provide targeted interventions and services. METHODS: A study was conducted in Sichuan Province, China, from November 2018 to April 2019, and 801 eligible participants were recruited by snowball sampling. Sociodemographic characteristics, AIDS-related characteristics, sexual behaviors, condom use behavior, and dimensions of HBM were investigated. Univariate, single multivariate, and summary multivariate models were employed to analyze the factors associated with consistent condom use. RESULTS: Of all participants, 39.1% and 53.6% had had anal sex with regular and nonregular partners in the last six months, respectively. Only 56.5% of them had used condoms consistently with regular partners, and only 60% of them had used condoms consistently with nonregular partners. When taking consistent condoms use with regular partners as the dependent variable, the dimensions of perceived threats (ORM = 1.28, 95% CI: 1.10, 1.49), perceived barriers (ORM = 0.70, 95% CI: 0.60, 0.82), self-efficacy (ORM = 1.23, 95% CI: 1.14, 1.32), and cues to action (ORM = 1.21, 95% CI: 1.02, 1.43) showed significant associations with the dependent variable. When taking consistent condoms use with nonregular partners as the dependent variable, the dimensions of perceived barriers (ORM = 0.77, 95% CI: 0.67, 0.89), self-efficacy (ORM = 1.22, 95% CI: 1.13, 1.32), and cues to action (ORM = 1.53, 95% CI: 1.30, 1.80) showed significant associations with the dependent variable. CONCLUSIONS: More attention should be focused on how to decrease the obstructive factors of condom use, how to improve the confidence of condom use, and how to layout more cues to action to promote consistent condom use behavior with regular and nonregular partners during anal sex among Chinese MSM.

LncRNA THRIL is upregulated in sepsis and sponges miR-19a to upregulate TNF-α in human bronchial epithelial cells.

BACKGROUND: Long non-coding RNAs (lncRNAs) have been demonstrated to play critical roles in various diseases. Our bioinformatics analysis showed that lncRNA TNFα and heterogenous nuclear ribonucleoprotein L (hnRNPL) related immunoregulatory LincRNA (THRIL) may interact with miR-19a, which targets TNF-α. This study aimed to explore the role of THRIL, an enhancer of LPS-induced inflammatory, in sepsis. METHODS: Research subjects of the present study included 66 sepsis patients and 66 healthy volunteers. The expression levels of THRIL, miR-19a and TNF-α in plasma samples from these participants were determined by RT-qPCR. The interaction between THRIL and miR-19a was explored by performing overexpression experiments in human bronchial epithelial cells (HBEpCs). The roles of THRIL, miR-19a and TNF-α in regulating the apoptosis of HBEpCs were analyzed by cell apoptosis assay. RESULTS: We found that THRIL was upregulated in sepsis patients. THRIL is predicted to interact with miR-19a, and the interaction was confirmed by dual-luciferase activity assay. However, THRIL and miR-19a did not affect the expression of each other. Instead, overexpression of THRIL resulted in the increased expression levels of TNF-α, a downstream target of miR-19a in HBEpCs. In HBEpCs, LPS treatment induced the overexpression of THRIL. Cell apoptosis analysis showed that overexpression of THRIL and TNF-α promoted the apoptosis of HBEpCs induced by LPS, while overexpression of miR-19a played an opposite role. Overexpression of THRIL attenuated the effects of overexpression of miR-19a. CONCLUSION: Therefore, THRIL is upregulated in sepsis and may sponge miR-19a to upregulate TNF-α, thereby promoting lung cell apoptosis.

Optical physics on chiral brominated azapirones: Bromophilone A and B.

In this work, we use the visualization method to study their intramolecular electric-magnetic interactions and reveal the physical mechanism of their electronic transition to explain the cause of the opposite ECD spectrum orientations. Azaphilone A and B are two chiral molecules, due to their differing chirality, the electronic circular dichroism (ECD) spectra of bromophilone A and B are very different at 431 nm. Based on the two-step transition process, the charge-transfer characteristics of the corresponding two-photon excited states of the two chiral molecules are analysed in detail by calculating the photoinduced charge transfer and electron-hole coherence in the two-photon absorption (TPA) process.

Donor-length dependent photoninduced charge transfer in two-photon absorption.

In this paper, we study the donor-length dependent photoinduced charge transfer in two-photon absorption (TPA). In the donor-acceptor (D-A) system of oligo-thiophene-fullerene, two kind of lengths of oligo-thiophene are chosen to study the donor-length dependent photoinduced charge transfer in TPA. It is found that donor length can significantly influence the rate of charge transfer. When the donor length is quarter-thiophene, the rate of charge transfer is less than 50%; while with the increase of donor-length to octant-thiophene, the rate of charge transfer can be reach up to 100%. The transition channels of photoinduced charge transfer in TPA are visualized with transition density matrix and charge difference density. Our results promote deeper understanding and rational design for donor-acceptor system with large rate of photoinduced charge transfer in TPA.

Space-Confined Synthesis of Core-Shell BaTiO3@Carbon Microspheres as a High-Performance Binary Dielectric System for Microwave Absorption.

Binary dielectric composites are viewed as a kind of promising candidate for conventional magnetic materials in the field of microwave absorption. Herein, we demonstrate the successful fabrication of core-shell BaTiO3@carbon microspheres through a space-confined strategy. The electromagnetic properties of BaTiO3@carbon microspheres can be easily tailored by manipulating the relative content of carbon shells. It is confirmed that dielectric loss of these composites mainly benefits from conductivity loss, dipole orientation polarization, and interfacial polarization, and the core-shell configuration shows its positive contribution to the reinforcement of interfacial polarization. When the content of carbon shells is optimized, the as-obtained composite will display excellent microwave-absorption performance due to decent attenuation and well-matched impedance. The strongest reflection loss can reach up to -88.5 dB at 6.9 GHz with the absorber thickness of 3.0 mm, and the qualified bandwidth below -10.0 dB covers 9.0-12.0 GHz, when the thickness is designated at 2.0 mm. Such a performance in the X band is superior to those of most typical binary dielectric systems. More importantly, these BaTiO3@carbon microspheres maintain good performance after being treated under high-temperature and acidic conditions for a long time, manifesting their promising prospect for practical application. It is believed that these results may be helpful for the development of multicomponent dielectric systems as high-performance microwave absorbing materials.

Transformation from Quantum to Classical Mode: the Size Effect of Plasmon in 2D Atomic Cluster System.

On the basis of tight-binding approximation, the energy absorption of 2D atomic clusters is calculated by the linear response theory. Through the energy-absorption peaks in the presence of different external potentials, various types of plasmon modes are specified in clusters with dozens to hundreds atoms, such as transverse dipole plasmon, longitudinal dipole plasmon, transverse quadrupole plasmon, and longitudinal quadrupole plasmon. Moreover, the transformation of plasmon from quantum to classical mode is observed in clusters with different shape and different electron density. The particular transformation process demonstrate that: there are only a few modes of plasmon in clusters with few-atoms; as the number of atoms in cluster is increased, the number of plasmon modes increases, the gaps between plasmon frequencies become smaller, the quantum modes of plasmon gradually evolve into continuous modes, and the dispersion of quantum-mode plasmon gradually transforms into the one of classical 2D plasmon. Such process reveals the size effect of plasmon in 2D clusters, which can be explained by the fact that the energy levels near the Fermi energy are denser and more compact in larger-size clusters.

Photoinduced charge transfer by one and two-photon absorptions: physical mechanisms and applications.

We review photoinduced charge transfer in organic solar cells without and with an external electric field and then we introduce the visualization methods of the transition density, charge difference density and transition density matrix for the analysis of the photoinduced charge transfer in a neutral system and a charged system excited by one-photon and two-photon absorption. This review will not only promote a deeper understanding of the available theories and methods of PICT, but also lead to further developments in this field.

Prussian blue analogues derived magnetic FeCo alloy/carbon composites with tunable chemical composition and enhanced microwave absorption.

A series of magnetic FeCo alloy/carbon composites have been successfully prepared through in situ pyrolysis of Prussian blue analogues (PBAs) with different Fe/Co ratios. The Fe/Co ratio can affect the crystalline phase, particle size, and magnetic property of the FeCo alloy particles, as well as the relative graphitization degree of the carbon frameworks. As a result, the electromagnetic functions of these composites will be highly associated with the Fe/Co ratio, where high Co content is beneficial to the formation of strong dielectric loss and moderate Co content can facilitate the magnetic loss. When Fe/Co ratio reaches 1:1, the as-obtained composite (sample S4) displays excellent reflection loss characteristics with powerful absorption in a very broad frequency range (over -10 dB in 3.2-18.0 GHz), which is superior to those of single magnetic metal (Fe or Co)/carbon composite derived from PBAs, as well as many previously reported FeCo alloy/carbon composites. Electromagnetic analysis reveals that the excellent microwave absorption of sample S4 benefits from its preferable matching of characteristic impedance and good attenuation ability toward incident electromagnetic waves. These results provide new insight into the fabrication of carbon-based magnetic composites with enhanced microwave absorption by rationally manipulating the chemical composition of magnetic components.

Constructing Uniform Core-Shell PPy@PANI Composites with Tunable Shell Thickness toward Enhancement in Microwave Absorption.

Highly uniform core-shell composites, polypyrrole@polyaniline (PPy@PANI), have been successfully constructed by directing the polymerization of aniline on the surface of PPy microspheres. The thickness of PANI shells, from 30 to 120 nm, can be well controlled by modulating the weight ratio of aniline and PPy microspheres. PPy microspheres with abundant carbonyl groups have very strong affinity to the conjugated chains of PANI, which is responsible for the spontaneous formation of uniform core-shell microstructures. However, the strong affinity between PPy microspheres and PANI shells does not promote the diffusion or reassembly of two kinds of conjugated chains. Coating PPy microspheres with PANI shells increases the complex permittivity and creates the mechanism of interfacial polarization, where the latter plays an important role in increasing the dielectric loss of PPy@PANI composites. With a proper thickness of PANI shells, the moderate dielectric loss will produce well matched characteristic impedance, so that the microwave absorption properties of these composites can be greatly enhanced. Although PPy@PANI composites herein consume the incident electromagnetic wave by absolute dielectric loss, their performances are still superior or comparable to most PANI-based composites ever reported, indicating that they can be taken as a new kind of promising lightweight microwave absorbers. More importantly, microwave absorption of PPy@PANI composites can be simply modulated not only by the thickness of the absorbers, but also the shell thickness to satisfy the applications in different frequency bands.

Cloning and biochemical properties of CDPK gene OsCDPK14 from rice.

A rice CDPK gene, OsCDPK14 (AY144497), was cloned from developing caryopses of rice (Oryza sativa cv. Zhonghua 15). Its cDNA sequence (1922 bp) contains an ORF encoding a 514 amino acids protein (56.7kD, pl 5.18). OsCDPK14 shows the typical structural features of the CDPK family, including a conserved catalytic Ser/Thr kinase domain, an autoinhibitory domain and a CaM-like domain with four putative Ca2+-binding EF hands. Subcellular targeting indicated that OsCDPK14 was located in the cytoplasm, probably due to the absence of myristoylation and palmitoylation motifs. OsCDPK14 was expressed in Escherichia coli and purified from bacterial extracts. The recombinant protein was shown to be a functional protein kinase using Syntide-2, a synthetic peptide. Kinase activity was shown to be Ca2+-dependent, and this activation was strongly enhanced by Mn2+ and inhibited by W7 in vitro. These results provide significant insights into the regulation and biochemical properties of OsCDPK14, suggesting OsCDPK14 may be a signal factor of cytoplasm in rice plant.