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The development of a resistance switching (RS) memory cell that contains rectification functionality in itself, highly reproducible RS performance, and electroforming-free characteristics is an impending task for the development of resistance switching random access memory. In this work, a two-layered dielectric structure consisting of HfO2 and Ta2O5 layers, which are in contact with the TiN and Pt electrode, is presented for achieving these tasks simultaneously in one sample configuration. The HfO2 layer works as the resistance switching layer by trapping or detrapping of electronic carriers, whereas the Ta2O5 layer remains intact during the whole switching cycle, which provides the rectification. With the optimized structure and operation conditions for the given materials, excellent RS uniformity, electroforming-free, and self-rectifying functionality could be simultaneously achieved from the Pt/Ta2O5/HfO2/TiN structure. [ABSTRACT FROM AUTHOR]

Various array types of 1-diode and 1-resistor stacked crossbar array (1D1R CA) devices composed of a Schottky diode (SD) (Pt/TiO2/Ti/Pt) and a resistive switching (RS) memory cell (Pt/TiO2/Pt) are fabricated and their performances are investigated. The unit cell of the 1D1R CA device shows high RS resistance ratio (≈103 at 1.5 V) between low and high resistance state (LRS and HRS), and high rectification ratio (≈105) between LRS and reverse-state SD. It also shows a short RS time of <50 ns for SET (resistance transition from HRS to LRS), and ≈600 ns for RESET (resistance transition from LRS to HRS), as well as stable RS endurance and data retention characteristics. It is experimentally confirmed that the selected unit cell in HRS (logically the 'off' state) is stably readable when it is surrounded by unselected LRS (logically the 'on' state) cells, in an array of up to 32 × 32 cells. The SD, as a highly non-linear resistor, appropriately controls the conducting path formation during the switching and protects the memory element from the noise during retention. [ABSTRACT FROM AUTHOR]

BACKGROUND: The increase in drug-resistant bacteria and the ban on antibiotic growth promoters worldwide make the search for novel means of preventing bacterial infection and promoting growth performance imperative. In this sense, antimicrobial peptides are thought to be ideal candidates owing to their antimicrobial properties, broad spectrum of activity and low propensity for development of bacterial resistance. The aim of the present study was to investigate the effect of dietary supplementation with antimicrobial peptide-P5 (AMP-P5) on weanling pig nutrition. RESULTS: A total of 240 weanling pigs were allotted to four treatments on the basis of initial body weight. There were four replicates in each treatment, with 15 pigs per replicate. Dietary treatments were negative control (NC, basal diet without antimicrobial), positive control (PC, basal diet + 1.5 g kg−1 apramycin), basal diet with 40 mg kg−1 AMP-P5 (P5-40) and basal diet with 60 mg kg−1 AMP-P5 (P5-60). Pigs fed the PC or P5-60 diet showed improved ( P < 0.05) overall growth performance, apparent total tract digestibility of dry matter, crude protein and gross energy and reduced ( P < 0.05) faecal and intestinal coliforms compared with pigs fed the NC diet. CONCLUSION: The results obtained in this study indicate that dietary supplementation with 60 mg kg−1 AMP-P5 has the potential to improve the growth performance and apparent total tract digestibility of nutrients and reduce coliforms in weanling pigs. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Resistance switching behaviors in a \Pt/In2\Ga2 \ZnO7 \break \ (\IGZO)/\TiO2/\Pt sample were examined for their potential use in diode-free memory integration. The In-Ga-Zn-O (IGZO) layer worked as the semiconductor layer, exhibiting accumulation or depletion of carriers depending on the polarity of the bias. Electroforming was possible only under the IGZO depletion condition due to the limited background leakage current flow. The repeated set/reset operation was also observed under the depletion condition. While the reset was possible, set was impeded by the high background current flow of the IGZO layer under the accumulation condition. [ABSTRACT FROM AUTHOR]

Ru nano-dots were embedded in a Pt/TiO2/Pt resistive switching cell to improve the uniformity of the switching parameters. The TiO2 film grown on the Ru nano-dots had a rutile structure locally whereas other parts of the TiO2 film had an anatase structure. The rutile-structured TiO2 formed conducting filaments easily and their rupture was much more uniform than the randomized ones in anatase TiO2. This largely improved the resistance uniformity at the reading voltage during the repeated resistance switching events. The improvement was also attributed to the high leakage current of the pristine sample at the reading voltage. [ABSTRACT FROM AUTHOR]

A true random number generator (TRNG) based on the stochastic delay and relaxation times of the threshold switching (TS) behavior in a Pt/HfO2/TiN memristor is proposed. The stochasticities of this device are attributed to its electron trapping and detrapping processes. This electronic‐switching‐based memristor exhibits several advantages, such as low power consumption and high reliability. A new circuit is designed to improve the simplicity, miniaturization, and lifetime of TRNG. The bitstreams collected from this TRNG pass the National Institute of Standards and Technology randomness tests without postprocessing, verifying the feasibility of adopting the memristor in hardware security applications. The bit generation rate in this work is sufficient for encryption applications requiring low power and low speed. A true random number generator (TRNG) based on a threshold switching behavior in a Pt/HfO2/TiN (PHT) memristor is proposed. The PHT memristor has stochastic delay and relaxation times, which are attributed to electron trapping and detrapping processes. A new circuit is designed to reduce the circuit size and to further improve the TRNG lifetime. [ABSTRACT FROM AUTHOR]

3DXP memory has emerged as the most powerful next generation non‐volatile memory. In article number 1700152, Cheol Seong Hwang and co‐workers demonstrate a 3DXP memory with double‐layer resistive‐switching random‐access‐memory architecture. The integrated diode shows the highest cell‐selector performance reported to date. A novel sensing scheme optimized for the device structure enhances the feasibility of ultra‐high‐density 3DXP memory realization. [ABSTRACT FROM AUTHOR]

A biological receptor serves as sensory transduction from an external stimulus to an electrical signal. It allows humans to better match the environment by filtering out repetitive innocuous information and recognize potentially damaging stimuli through key features, including adaptive and maladaptive behaviors. Herein, for the first time, the authors develop substantial artificial receptors involving both adaptive and maladaptive behaviors using diffusive memristor. Metal‐oxide nanorods (NR) as a switching matrix enable the electromigration of an active metal along the surface of the NRs under electrical stimulation, resulting in unique surface‐dominated switching dynamics with the advantage of fast Ag migration and fine controllability of the conductive filament. To experimentally demonstrate its potential application, a thermoreceptor system is constructed using memristive artificial receptors. The proposed surface‐dominated diffusive memristor allows the direct emulation of the biological receptors, which represents an advance in the bioinspired technology adopted in creating artificial intelligence systems. [ABSTRACT FROM AUTHOR]

Non-erosive reflux disease (NERD) pathogenesis has not been thoroughly evaluated. Here, we assessed the response of patients with NERD to proton pump inhibitor (PPI) therapy; changes in the microbiome and biologic marker expression in the esophageal mucosa were also evaluated. Patients with NERD (n = 55) received esomeprazole (20 mg) for eight weeks. The treatment response was evaluated at baseline, week four, and week eight. Esophageal mucosal markers and oropharyngeal and esophageal microbiomes were analyzed in patients who underwent upper gastrointestinal endoscopy at screening (n = 18). Complete and partial response rates at week eight were 60.0% and 32.7% for heartburn, and 61.8% and 29.1% for regurgitation, respectively. The expressions of several inflammatory cytokines, including IL-6, IL-8, and NF-κB, were decreased at week eight. Streptococcus, Haemophilus, Prevotella, Veillonella, Neisseria, and Granulicatella were prevalent regardless of the time-point (baseline vs. week eight) and organ (oropharynx vs. esophagus). The overall composition of oropharyngeal and esophageal microbiomes showed significant difference (P = 0.004), which disappeared after PPI therapy. In conclusion, half-dose PPI therapy for eight weeks could effectively control NERD symptoms. The expression of several inflammatory cytokines was reduced in the esophagus, and oropharyngeal and esophageal microbiomes in patients with NERD showed significant difference. However, the microbial compositions in the oropharynx and esophagus were not affected by PPI therapy in this study. Impact of PPI on the microbiome in patients with NERD should be more investigated in future studies. [ABSTRACT FROM AUTHOR]

A self-rectifying ferroelectric tunnel junction that employs a HfO 2 /ZrO 2 /HfO 2 superlattice (HZH SL) combined with Al 2 O 3 and TiO 2 layers is proposed. The 6 nm-thick HZH SL effectively suppresses the formation of non-ferroelectric phases while increasing remnant polarization ( P r ). This enlarged P r modulates the energy barrier configuration, consequently achieving a large on/off ratio of 1273 by altering the conduction mechanism from off-state thermal injection to on-state Fowler-Nordheim tunneling. Moreover, the asymmetric Schottky barriers at the top TiN/TiO 2 and bottom HfO 2 /Pt interfaces enable a self-rectifying property with a rectifying ratio of 1550. Through calculations and simulations it is found that the device demonstrates potential for achieving an integrated array size exceeding 7k while maintaining a 10% read margin, and shows potential for application in artificial synapses for neuromorphic computing with an image recognition accuracy above 92%. Finally, the self-rectifying behavior and device-to-device variation reliability are confirmed in a 9 × 9 crossbar array structure.

Inspired by the functions of biological neural networks, volatile memristors are essential for implementing neuromorphic computing. These devices enable large-scale and energy-efficient data processing by emulating neural functionalities through dynamic resistance changes. The threshold switching characteristics of volatile memristors, which are driven by various mechanisms in materials ranging from oxides to chalcogenides, make them versatile and suitable for neuromorphic computing systems. Understanding these mechanisms and selecting appropriate devices for specific applications are crucial for optimizing the performance. However, the existing literature lacks a comprehensive review of switching mechanisms, their compatibility with different applications, and a deeper exploration of the spatiotemporal processing capabilities and inherent stochasticity of volatile memristors. This review begins with a detailed analysis of the operational principles and material characteristics of volatile memristors. Their diverse applications are then explored, emphasizing their role in crossbar arrays, artificial receptors, and neurons. Furthermore, the potential of volatile memristors in artificial inference systems and reservoir computing is discussed, due to their spatiotemporal processing capabilities. Hardware security applications and probabilistic computing are also examined, where the inherent stochasticity of the devices can improve the system robustness and adaptability. To conclude, the suitability of different switching mechanisms for various applications is evaluated, and future perspectives for the development and implementation of volatile memristors are presented. This review aims to fill the gaps in existing research and highlight the potential of volatile memristors to drive innovation in neuromorphic computing, paving the way for more efficient and powerful computational paradigms.

Although rare, there is ongoing research into biomarkers that predict the onset and recurrence of gastric cancer, particularly focusing on substances found in exosomes. Long non-coding RNAs (lncRNAs) have garnered attention for their potential in diagnosing gastric cancer. This study investigates the role of lncRNAs in gastric cancer, focusing on their presence in exosomes as potential biomarkers for the disease's onset and recurrence. We utilized the ArrayStar Human LncRNA array 2.0 to analyze lncRNA expression in tissues from early-stage gastric cancer patients. Our analysis highlighted LINC00853, which was significantly upregulated in cancer tissues and implicated in promoting epithelial-mesenchymal transition via the MAP17/PDZK1/AKT pathway. Functional studies on AGS and MKN74 gastric cancer cell lines demonstrated that LINC00853 facilitates cell proliferation, invasion, and migration. Additionally, RNA immunoprecipitation and electrophoretic mobility shift assays confirmed LINC00853 interaction with MAP17. Importantly, LINC00853 was also detected in exosomes from both patient samples and cell lines, and its downregulation led to decreased tumorigenicity in AGS cells. These findings suggest that both cellular and exosomal LINC00853 contribute to gastric cancer pathogenesis and may serve as valuable biomarkers for the disease., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

HfO 2 shows promise for emerging ferroelectric and resistive switching (RS) memory devices owing to its excellent electrical properties and compatibility with complementary metal oxide semiconductor technology based on mature fabrication processes such as atomic layer deposition. Oxygen vacancy (V o ), which is the most frequently observed intrinsic defect in HfO 2 -based films, determines the physical/electrical properties and device performance. V o influences the polymorphism and the resulting ferroelectric properties of HfO 2 . Moreover, the switching speed and endurance of ferroelectric memories are strongly correlated to the V o concentration and redistribution. They also strongly influence the device-to-device and cycle-to-cycle variability of integrated circuits based on ferroelectric memories. The concentration, migration, and agglomeration of V o form the main mechanism behind the RS behavior observed in HfO 2 , suggesting that the device performance and reliability in terms of the operating voltage, switching speed, on/off ratio, analog conductance modulation, endurance, and retention are sensitive to V o . Therefore, the mechanism of V o formation and its effects on the chemical, physical, and electrical properties in ferroelectric and RS HfO 2 should be understood. This study comprehensively reviews the literature on V o in HfO 2 from the formation and influencing mechanism to material properties and device performance. This review contributes to the synergetic advances of current knowledge and technology in emerging HfO 2 -based semiconductor devices., (© 2023. The Author(s).)

In the biological nervous system, the integration and cooperation of parallel system of receptors, neurons, and synapses allow efficient detection and processing of intricate and disordered external information. Such systems acquire and process environmental data in real-time, efficiently handling complex tasks with minimal energy consumption. Memristors can mimic typical biological receptors, neurons, and synapses by implementing key features of neuronal signal-processing functions such as selective adaption in receptors, leaky integrate-and-fire in neurons, and synaptic plasticity in synapses. External stimuli are sensitively detected and filtered by "artificial receptors," encoded into spike signals via "artificial neurons," and integrated and stored through "artificial synapses." The high operational speed, low power consumption, and superior scalability of memristive devices make their integration with high-performance sensors a promising approach for creating integrated artificial sensory systems. These integrated systems can extract useful data from a large volume of raw data, facilitating real-time detection and processing of environmental information. This review explores the recent advances in memristor-based artificial sensory systems. The authors begin with the requirements of artificial sensory elements and then present an in-depth review of such elements demonstrated by memristive devices. Finally, the major challenges and opportunities in the development of memristor-based artificial sensory systems are discussed., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors. Exploration published by Henan University and John Wiley & Sons Australia, Ltd.)