In the study of resistive random access memory using GeTeO x film as the switching layer, the device performed excellent property of bipolar resistive switching (BRS), which could be gradually ...transformed to the complementary resistive switching (CRS) by varying SET process current compliance. The conductive filament conduction mechanism of BRS could be verified by electrical characteristics and reliable data fitting. Through increasing current compliance of the SET process, CRS could be achieved due to higher activity of oxygen vacancies originated from the intensified thermal effect. This paper was beneficial to understand the switching mechanisms of BRS and CRS and provide a method to realize interconversion. Moreover, it was also a potential and promising device to be applied in the neurosynaptic biomimetic field.
Memristor-based neural network (MNN) has made breakthroughs in image classification, but for complex video recognition, the required deep MNN will inevitably be more sensitive to non-ideal effects. ...In this work, we evaluate a memristor-based 3-D convolutional neural network (CNN) for action recognition and incorporate various non-ideal effects at the circuit and device level. Hardware-friendly schemes such as time division multiplexing (TDM) and updating with increasing thresholds are also described. Furthermore, a strategy combining forward averaging and mapping back is proposed to alleviate the IR drop effect. By setting the intersection conductance as the differential reference, deep MNNs are able to adapt to the updating asymmetry. Under the above adaptive strategies and in situ training, the network achieves an accuracy of 92.9% higher than the software and requires fewer updating pulses.
A graphite oxide (GO) semiconductor photocatalyst with an apparent bandgap of 2.4–4.3 eV is synthesized by a modified Hummers' procedure. The as‐synthesized GO photocatalyst has an interlayer spacing ...of 0.42 nm because of its moderate oxidation level. Under irradiation with UV or visible light, this GO photocatalyst steadily catalyzes H2 generation from a 20 vol % aqueous methanol solution and pure water. As the GO sheets extensively disperse in water, a cocatalyst is not required for H2 generation over the GO photocatalyst. During photocatalytic reaction, the GO loses some oxygen functional groups, leading to bandgap reduction and increased conductivity. This structural variation does not affect the stable H2 generation over the GO. The encouraging results presented in this study demonstrate the potential of graphitic materials as a medium for water splitting under solar illumination.
Graphite oxide with an appropriate oxidization level serves as a photocatalyst for stable H2 generation from water in an aqueous solution or pure water. The energy level of the conduction band edge of the graphite oxide is high enough to effectively donate electrons for H2 generation from water in the presence of methanol.
The gut microbiota-derived metabolite, trimethylamine N-oxide (TMAO) plays an important role in cardiovascular disease (CVD). The fasting plasma TMAO was shown as a prognostic indicator of CVD ...incident in patients and raised the interest of intervention targeting gut microbiota. Here we develop a clinically applicable method called oral carnitine challenge test (OCCT) for TMAO-related therapeutic drug efforts assessment and personalising dietary guidance.
A pharmacokinetic study was performed to verify the design of OCCT protocol. The OCCT was conducted in 23 vegetarians and 34 omnivores to validate gut microbiota TMAO production capacity. The OCCT survey was integrated with gut microbiome, host genotypes, dietary records and serum biochemistry. A humanised gnotobiotic mice study was performed for translational validation.
The OCCT showed better efficacy than fasting plasma TMAO to identify TMAO producer phenotype. The omnivores exhibited a 10-fold higher OR to be high TMAO producer than vegetarians. The TMAO-associated taxa found by OCCT in this study were consistent with previous animal studies. The TMAO producer phenotypes were also reproduced in humanised gnotobiotic mice model. Besides, we found the faecal
gene was not associated with TMAO production; therefore, other key relevant microbial genes might be involved. Finally, we demonstrated the urine TMAO exhibited a strong positive correlation with plasma TMAO (r=0.92, p<0.0001) and improved the feasibility of OCCT.
The OCCT can be used to identify TMAO-producer phenotype of gut microbiota and may serve as a personal guidance in CVD prevention and treatment.
NCT02838732; Results.
Fast recovery diodes (FRD) are widely used in transformer circuits for fast switching. Generally, in order to reduce forward voltage to achieve fast switching, the doping concentration is increased ...to reduce on-state resistance (R on ). This, however, will also increase reverse bias leakage as well as recovery time, resulting in a large amount of excess power consumption. In this letter, we use a unique low temperature supercritical fluid treatment process (LTSCF) to reduce this reverse bias leakage current, without affecting the on-state characteristics or switching characteristics. Experimental results show that the device's average reverse bias leakage was reduced by 65% after LTSCF.
Higher chemokine C-X-C motif ligand 5 (CXCL5) level was observed in type 2 diabetes mellitus (DM) patients; however, its role in diabetic vasculopathy was not clarified. This study aimed to explore ...the impacts and mechanistic insights of CXCL5 in neovasculogenesis and wound healing in DM.
Endothelial progenitor cells (EPCs) and human aortic endothelial cells (HAECs) were used in vitro. Streptozotocin-induced diabetic mice and Lepr
/JNarl mice were used as type 1 and type 2 DM models. Moreover, CXCL5 knockout mice were used to generate diabetic mice. Hindlimb ischemia surgery, aortic ring assays, matrigel plug assay, and wound healing assay were conducted.
CXCL5 concentrations were increased in plasma and EPCs culture medium from type 2 DM patients. CXCL5 neutralizing antibody upregulated vascular endothelial growth factor (VEGF)/stromal cell-derived factor-1 (SDF-1) and promoted cell function in EPCs from type 2 DM patients and high glucose-treated EPCs from non-DM subjects as well as HAECs. CXCL5 directly up-regulated interleukin (IL)-1β/IL-6/tumor necrosis factor-α and down-regulated VEGF/SDF-1 via ERK/p65 activation through chemokine C-X-C motif receptor 2 (CXCR2). CXCL5 neutralizing antibody recovered the blood flow after hindlimb ischemia, increased circulating EPC number, and enhanced VEGF and SDF-1 expression in ischemic muscle. CXCL5 suppression promoted neovascularization and wound healing in different diabetic animal models. The above observation could also be seen in streptozotocin-induced CXCL5 knockout diabetic mice.
CXCL5 suppression could improve neovascularization and wound healing through CXCR2 in DM. CXCL5 may be regarded as a potential therapeutic target for vascular complications of DM.
This letter investigates the characteristics of doping gadolinium (Gd) in an indium-tin-oxide (ITO) electrode in HfO 2 -based resistive random access memory (RRAM). Identical bottom electrodes and ...insulators were made but then capped by either pure ITO or a Gd:ITO top electrode. Doping Gd in the ITO electrode produces lower operation currents in both high-resistance state (HRS) and low-resistance state (LRS) as well as enlarging the memory window. This excellent performance suggests a remarkable potential to improve RRAM applications. Schottky emission mechanism dominates both HRS and LRS according to current fitting results, and is confirmed by temperature effect experiments. The resistive switching behavior of the Gd:ITO device is explained by our model and is also confirmed by material analysis and electrical measurements. Furthermore, reliability tests verify the Gd:ITO device's capability to perform data storage as a nonvolatile memory.
We report on a highly compact, one diode–one resistor (1D–1R) nanopillar device architecture for SiO x -based ReRAM fabricated using nanosphere lithography (NSL). The intrinsic SiO x -based resistive ...switching element and Si diode are self-aligned on an epitaxial silicon wafer using NSL and a deep-Si-etch process without conventional photolithography. AC-pulse response in 50 ns regime, multibit operation, and good reliability are demonstrated. The NSL process provides a fast and economical approach to large-scale patterning of high-density 1D–1R ReRAM with good potential for use in future applications.
In-memory computing based on memristive logic is considered as a prospective non von Neumann computing paradigm. In this letter, we systematically analyze the four-variable logic method and map it ...into the operation of two anti-serial complementary memristors in the crossbar array architecture. Arbitrary Boolean logic can be implemented within three cycles with the experimental evidence of reconfigurable NAND, NOR, and XOR logic using Pt/HfO 2 /TiN devices. Taking advantage of the functional flexibility, a parallel 1-bit full adder that can be realized in 8 cycles within a <inline-formula> <tex-math notation="LaTeX">\textsf {4}\times \textsf {3} </tex-math></inline-formula> array has been designed and verified in simulation.
Background-Elevated circulating fatty-acid-binding protein 4 (FABP4) levels may be linked with cardiovascular events. This study aimed to investigate the mechanistic role of FABP4 in atherosclerosis. ...Methods-We recruited 22 patients with angiographically proven coronary artery disease (CAD) and 40 control subjects. Mononuclear cells (MNCs) and human coronary endothelial cells (HCAECs) were used for in vitro study. Results-Patients with CAD were predominantly male with an enhanced prevalence of hypertension, diabetes, and smoking history. FABP4 concentrations were up-regulated in culture supernatants of MNCs from CAD patients, which were positively correlated with the patients' age, waist-hip ratio, body mass index, serum creatinine, type 2 diabetes, and the presence of hypertension. The adhesiveness of HCAECs to monocytic cells can be activated by FABP4, which was reversed by an FABP4 antibody. FABP4 blockade attenuated the oxidized low-density lipoprotein (oxLDL)-induced expression of ICAM-1, VCAM-1, and P-selectin. FABP4 impaired the tube formation and migration via the ERK/JNK/STAT-1 signaling pathway. FABP4 suppressed phosphorylation of eNOS and expression of SDF-1 protein, both of which can be reversed by treatment with VEGF. Blockade of FABP4 also improved the oxLDL-impaired cell function. Conclusion-We discovered a novel pathogenic role of FABP4 in MNC activation and endothelial dysfunction in atherosclerosis. FABP4 may be a therapeutic target for modulating atherosclerosis.
PDF
