Loss of OsMATE6 Function Enhances Drought Resistance Without Yield Penalty by Regulating Stomatal Closure in Rice.

Drought is one of the most severe environmental factors limiting plant growth and crop yield, necessitating the identification of genes that enhance drought resistance for crop improvement. Through screening an ethyl methyl sulfonate-mutagenized rice mutant library, we isolated the PEG tolerance mutant 97-1 (ptm97-1), which displays enhanced resistance to osmotic and drought stress, and increased yield under drought conditions. A point mutation in OsMATE6 was identified as being associated with the drought-resistant phenotype of ptm97-1. The role of OsMATE6 in conferring drought resistance was confirmed by additional OsMATE6 knockout mutants. OsMATE6 is expressed in guard cells, shoots and roots and the OsMATE6-GFP fusion protein predominantly localizes to the plasma membrane. Our ABA efflux assays suggest that OsMATE6 functions as an ABA efflux transporter; mutant protoplasts exhibited a slower ABA release rate compared to the wild type. We hypothesize that OsMATE6 regulates ABA levels in guard cells, influencing stomatal closure and enhancing drought resistance. Notably, OsMATE6 knockout mutants demonstrated greater yields under field drought conditions compared to wild-type plants, highlighting OsMATE6 as a promising candidate for improving crop drought resistance.

Fine-tuning of IPA1 transactivation activity by E3 ligase IPI7-mediated non-proteolytic K29-ubiquitination during Magnaporthe oryzae infection.

The Ideal Plant Architecture 1 (IPA1) transcription factor promotes rice yield and immunity through phosphorylation at its amino acid residue Ser163 as a switch. Although phosphorylated IPA1 mimic, IPA1(S163D), directly targets the promoter of immune response gene WRKY45, it cannot activate its expression. Here, we identified a co-activator of IPA1(S163D), a RING-finger E3 ligase IPA1 interactor 7 (IPI7), which fine-tunes the transcriptional activity of IPA1 to timely promote plant immunity and simultaneously maintain growth for yield. IPI7 interacts with IPA1 and promotes K29-polyubiquitination of IPA1 in vitro and in vivo. However, the stability of IPA1 protein is not affected by IPI7-mediated ubiquitination. The IPI7-promoted K29-polyubiquitination of IPA1 is induced by Magnaporthe oryzae infection and required for phosphorylated IPA1 to transactivate WRKY45 expression for immune response but not for plain IPA1 to transactivate DENSE AND ERECT PANICLES 1 (DEP1) expression for panicle development. IPI7 knockout impairs IPA1-mediated immunity but not yield. Our study reveals that plants utilize non-proteolytic K29-ubiquitination as a response to pathogen infection to fine-tune IPA1 transactivation activity for promoting immunity.

Impaired 2',3'-cyclic phosphate tRNA repair causes thermo-sensitive genic male sterility in rice.

Hybrid rice, widely planted in Asia, is pathogen resistant and has superior yields, making it a major contributor to global food security. The two-line hybrid rice system, which utilizes mutants exhibiting photo-/thermo-sensitive genic male sterility (P/TGMS), is the leading hybrid rice breeding technology. Mutations in THERMO-SENSITIVE GENIC MALE STERILE 5 (TMS5) accounts for over 95% of current TGMS lines. We previously found that tms5 carries a mutation in ribonuclease ZS1. Despite its importance for breeding robust rice lines, the mechanism underlying tms5-mediated TGMS remains elusive. Here, we demonstrate that TMS5 is a tRNA 2',3'-cyclic phosphatase. The tms5 mutation leads to accumulation of 2',3'-cyclic phosphate (cP)-ΔCCA-tRNAs (tRNAs without 3' CCA ended with cP), which is exacerbated by high temperatures, and reduction in the abundance of mature tRNAs, particularly alanine tRNAs (tRNA-Alas). Overexpression of tRNA-Alas in the tms5 mutant restores male fertility to 70%. Remarkably, male fertility of tms5 mutant is completely restored at high temperatures by knocking out OsVms1 which encodes the enzyme for cP-ΔCCA-tRNA generation. Our study reveals the mechanism underlying tms5-mediated TGMS in rice and provides mechanistic insight into the further improvement of TGMS in hybrid crop development.

Manipulating long-term fates of sonoporated cells by regulating intracellular calcium for improving sonoporation-based delivery.

Sonoporation-based delivery has great promise for noninvasive drug and gene therapy. After short-term membrane resealing, the long-term function recovery of sonoporated cells affects the efficiency and biosafety of sonoporation-based delivery. It is necessary to identify the key early biological signals that influence cell fate and to develop strategies for manipulating the long-term fates of sonoporated cells. Here, we used a customized experimental platform with a single cavitating microbubble induced by a single ultrasound pulse (frequency: 1.5 MHz, pulse length:13.33 µs, peak negative pressure: ∼0.40 MPa) to elicit single-site reversible sonoporation on a single HeLa cell model. We used a living-cell microscopic imaging system to trace the long-term fates of sonoporated HeLa cells in real-time for 48 h. Fluorescence from intracellular propidium iodide and Fluo-4 was used to evaluate the degree of sonoporation and intracellular calcium fluctuation (ICF), respectively. Changes in cell morphology were used to assess the long-term cell fates (i.e., proliferation, arrest, or death). We found that heterogeneously sonoporated cells had different long-term fates. With increasing degree of sonoporation, the probability of normal (proliferation) and abnormal fates (arrest and death) in sonoporated cells decreased and increased, respectively. We identified ICF as an important early event for triggering different long-term fates. Reversibly sonoporated cells exhibited stronger proliferation and restoration at lower extents of ICF. We then regulated ICF dynamics in sonoporated cells using 2-APB or BAPTA treatment to reduce calcium release from intracellular organelles and enhance intracellular calcium clearance, respectively. This significantly enhanced the proliferation and restoration of sonoporated cells and reduced the occurrence of cell-cycle arrest and death. Finally, we found that the long-term fates of sonoporated cells at multiple sites and neighboring cells were also dependent on the extent of ICF, and that 2-APB significantly enhanced their viability and reduced death. Thus, using a single HeLa cell model, we demonstrated that regulating intracellular calcium can effectively enhance the proliferation and restoration capabilities of sonoporated cells, therefore rescuing the long-term viability of sonoporated cells. These findings add to our understanding of the biophysical process of sonoporation and help design new strategies for improving the efficiency and biosafety of sonoporation-based delivery.

Facilitating secretory expression of apple seed ß-glucosidase in Komagataella phaffii for the efficient preparation of salidroside.

Plant-derived ß-glucosidases hold promise for glycoside biosynthesis via reverse hydrolysis because of their excellent glucose tolerance and robust stability. However, their poor heterologous expression hinders the development of large-scale production and applications. In this study, we overexpressed apple seed ß-glucosidase (ASG II) in Komagataella phaffii and enhanced its production from 289 to 4322 U L-1 through expression cassette engineering and protein engineering. Upon scaling up to a 5-L high cell-density fermentation, the resultant mutant ASG IIV80A achieved a maximum protein concentration and activity in the secreted supernatant of 2.3 g L-1 and 41.4 kU L-1, respectively. The preparative biosynthesis of salidroside by ASG IIV80A exhibited a high space-time yield of 33.1 g L-1 d-1, which is so far the highest level by plant-derived ß-glucosidase. Our work addresses the long-standing challenge of the heterologous expression of plant-derived ß-glucosidase in microorganisms and presents new avenues for the efficient production of salidroside and other natural glycosides.

Energy Band-Modulated SnO Anodes with Improved Rate Capacity and Initial Coulombic Efficiency for Sodium-Ion Batteries.

An efficient interface and composition modification strategy is proposed to significantly increase the rate capacity and initial Coulombic efficiency (ICE) of SnO anodes via energy band structure modulation for Na-ion batteries (SIBs). The as-fabricated SnO@Bi@C material with Bi nanocrystals homogeneously dispersed on and around the SnO surface is prepared by an electrospinning method. The excellently dispersed Bi nanocrystals realize an effective interface contact with SnO and Na2O, which effectively lowers the electron conduction barriers and promotes sodium-ion release and transport upon the desodiation process, increasing the rate capacity and ICE of the SnO anode. The prepared SnO@Bi@C exhibits a much higher rate capacity up to 10 A g-1, except an improved ICE of 80.67%, compared to 57.38% of SnO@C. Importantly, the intercalation of Na+ between layer-structured Bi galleries provides a good basis for excellent cycle stability due to the highways constructed inside the prepared composites. This finding provides an effective tactic to establish ion transport high-speed channels, which essentially increase the rate performance and the ICE of the SnO-based anodes.

Identifying Core Genes Related to Low-Temperature Stress Resistance in Quinoa Seedlings Based on WGCNA.

Quinoa is a nutritious crop that is tolerant to extreme environmental conditions; however, low-temperature stress can affect quinoa growth, development, and quality. Considering the lack of molecular research on quinoa seedlings under low-temperature stress, we utilized a Weighted Gene Co-Expression Network Analysis to construct weighted gene co-expression networks associated with physiological indices and metabolites related to low-temperature stress resistance based on transcriptomic data. We screened 11 co-expression modules closely related to low-temperature stress resistance and selected 12 core genes from the two modules that showed the highest associations with the target traits. Following the functional annotation of these genes to determine the key biological processes and metabolic pathways involved in low-temperature stress, we identified four important transcription factors involved in resistance to low-temperature stress: gene-LOC110731664, gene-LOC110736639, gene-LOC110684437, and gene-LOC110720903. These results provide insights into the molecular genetic mechanism of quinoa under low-temperature stress and can be used to breed lines with tolerance to low-temperature stress.

Identification and core gene-mining of Weighted Gene Co-expression Network Analysis-based co-expression modules related to flood resistance in quinoa seedlings.

BACKGROUND: As an emerging food crop with high nutritional value, quinoa has been favored by consumers in recent years; however, flooding, as an abiotic stress, seriously affects its growth and development. Currently, reports on the molecular mechanisms related to quinoa waterlogging stress responses are lacking; accordingly, the core genes related to these processes were explored via Weighted Gene Co-expression Network Analysis (WGCNA). RESULTS: Based on the transcriptome data, WGCNA was used to construct a co-expression network of weighted genes associated with flooding resistance-associated physiological traits and metabolites. Here, 16 closely related co-expression modules were obtained, and 10 core genes with the highest association with the target traits were mined from the two modules. Functional annotations revealed the biological processes and metabolic pathways involved in waterlogging stress, and four candidates related to flooding resistance, specifically AP2/ERF, MYB, bHLH, and WRKY-family TFs, were also identified. CONCLUSIONS: These results provide clues to the identification of core genes for quinoa underlying quinoa waterlogging stress responses. This could ultimately provide a theoretical foundation for breeding new quinoa varieties with flooding tolerance.

CD69+ Vδ1γδ T cells are anti-tumor subpopulations in hepatocellular carcinoma.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC), one of the malignancies with a wide expression of stress ligands recognized by Vδ1γδ T cells, has received much attention in adoptive immunotherapy of γδ T cells. In this study, we aimed to identify the potential anti-tumor Vδ1γδ T subpopulations in HCC. METHODS: Healthy donors (HDs) and HCC patients were recruited from the Affiliated Cancer Hospital of Zhengzhou University. Blood and tumor tissue samples were obtained respectively. Bioinformatics methods were used to analyze total γδ T cells and subsets infiltration, overall survival of HCC patients with high and low infiltration level of Vδ1γδ T cells, and IFNG, granzyme A, granzyme B and perforin expression in TRDV1high/lowCD69high/low groups. CD69 expression and Vδ1γδT cells infiltration in HCC were detected by immunofluorescence. Phenotypic analysis of Vδ1γδ T cells in blood and tumor tissue samples were performed by flow cytometry. RESULTS: Vδ1γδ T cells infiltrating in HCC were associated with better clinical outcome. Study in tumor micro-environment (TME) of HCC demonstrated that not total Vδ1γδ T but CD69+ Vδ1γδ subset infiltration was associated with smaller tumor volume. Moreover, HCC patients simultaneously with high TRDV1 and CD69 expression produced more effector molecules and had longer survival time. Since Vδ1γδ T cells in the tumor microenvironment were often difficult to access, we demonstrated that CD69+ Vδ1γδ T cells also existed in peripheral blood mononuclear cells (PBMC) of HCC and displayed enhanced cytotoxic potentials than HDs. Finally, we investigated the functions and found that CD69+ Vδ1γδ T cells exhibited stronger tumor reactivities when challenged by tumor cells. CONCLUSIONS: CD69+ Vδ1γδ T cells are functional Vδ1γδ T cell subsets in patients with HCC. Circulating CD69+ Vδ1γδ T cell is a promising candidate in immunotherapy of HCC.

OsNLP3 enhances grain weight and reduces grain chalkiness in rice.

Grain weight, a key determinant of yield in rice (Oryza sativa L.), is governed primarily by genetic factors, whereas grain chalkiness, a detriment to grain quality, is intertwined with environmental factors such as mineral nutrients. Nitrogen (N) is recognized for its effect on grain chalkiness, but the underlying molecular mechanisms remain to be clarified. This study revealed the pivotal role of rice NODULE INCEPTION-LIKE PROTEIN 3 (OsNLP3) in simultaneously regulating grain weight and grain chalkiness. Our investigation showed that loss of OsNLP3 leads to a reduction in both grain weight and dimension, in contrast to the enhancement observed with OsNLP3 overexpression. OsNLP3 directly suppresses the expression of OsCEP6.1 and OsNF-YA8, which were identified as negative regulators associated with grain weight. Consequently, two novel regulatory modules, OsNLP3-OsCEP6.1 and OsNLP3-OsNF-YA8, were identified as key players in grain weight regulation. Notably, the OsNLP3-OsNF-YA8 module not only increases grain weight but also mitigates grain chalkiness in response to N. This research clarifies the molecular mechanisms that orchestrate grain weight through the OsNLP3-OsCEP6.1 and OsNLP3-OsNF-YA8 modules, highlighting the pivotal role of the OsNLP3-OsNF-YA8 module in alleviating grain chalkiness. These findings reveal potential targets for simultaneous enhancement of rice yield and quality.

Evaluation of the mechanistic basis for the antibacterial activity of ursolic acid against Staphylococcus aureus.

The antibiotics are generally regarded as the first choice approach to treat dairy mastitis, targeting the public health problems associated with the food safety and the emergence of antibioticresistant bacteria. The objective of the study was to evaluate the antibacterial efficacy of ursolic acid (UA) when used to treat Staphylococcus aureus and other isolates associated with bovine mastitis and to clarify the mechanistic basis for these effects. The bacteriostatic properties of UA extracted from Rosmarinus officinalis L. at four different purity levels were assessed by calculating minimum inhibitory concentration (MIC) values, while the synergistic effects of combining 98% UA with antibiotics were evaluated by measuring the fractional inhibitory concentration index (FICI). Changes in biofilm formation and the growth curves of the clinical isolates were assessed to clarify the bacteriostatic effect of UA. Furthermore, the cell wall integrity, protein synthesis, and reactive oxygen species (ROS) production were assessed to determine the antibacterial mechanism of UA treatment. Ultimately, UA was revealed to exhibit robust activity against Gram-positive bacteria including S. aureus (ATCC 25923), Streptococcus dysgalactiae (ATCC27957), Streptococcus agalactiae (ATCC13813), Enterococcus faecalis (ATCC29212), and Streptococcus mutans (ATCC25175). However, it did not affect Escherichia coli (ATCC 25922). The MIC values of UA preparations that were 98, 50, 30, and 10% pure against S. aureus were 39, 312, 625, and 625 µg/mL, respectively, whereas the corresponding MIC for E. coli was >5,000 µg/mL. The minimum bactericidal concentrations of 98% UA when used to treat three clinical S. aureus isolates (S4, S5, and S6) were 78, 78, and 156 µg/mL, respectively. Levels of biofilm formation for clinical S. aureus isolates decreased with increasing 98% UA concentrations. Above the MIC dose, UA treatment resulted in the dissolution of bacterial cell walls and membranes, with cells becoming irregularly shaped and exhibiting markedly impaired intracellular protein synthesis. S. aureus treated with 98% UA was able to rapidly promote intracellular ROS biogenesis. Together, these data highlight the promising utility of UA as a compound that can be used together with other antibiotics for the treatment of infections caused by S. aureus.

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Antibiotics are widely utilized in agriculture for the prevention and treatment of animal diseases. How-ever, the abuse and overuse of antibiotics progressively increase the risks of antibiotic residues and antibiotic resis-tance. The bioaccumulation and biomagnification of antibiotics through food chains will negatively affect ecological safety, and finally threaten human health. There are many shortages of traditional antibiotic detection techniques, such as complex procedures, complicated operation and time consuming, and thus are difficult to meet the demand of instant, efficient and accurate on-site detection. Therefore, it is crucial to develop rapid detection techniques of antibiotics to manage the application of antibiotics in agriculture. We reviewed the utilization, and management of antibiotics in animal husbandry, residual characteristics, and potential hazards of antibiotics in agricultural products, summarized the advancements in rapid detection techniques of antibiotics in agricultural products over the past five years, compared the advantages and disadvantages of different rapid detection techniques, and prospected the future development in this area. This review would provide a valuable reference to the control and point-of-care test of antibiotics in agricultural products.

Unveiling the activity difference cause and ring-opening reaction routes of typical radicals induced degradation of toluene.

This study employs five UV-AOPs (PMS, PDS, H2O2, NaClO and NaClO2) to produce radicals (•OH, SO4•-, ClO•, O2•- and 1O2) and further comparatively studies their activity sequence and activity difference cause in toluene degradation. The toluene mineralization efficiency as a descending order is 73 % (UV-PMS) > 71 % (UV-PDS) > 70 % (acidified-UV-NaClO) > 55 % (UV-H2O2) > 36 % (UV-NaClO) > 35 % (UV-NaClO2); that of conversion efficiency is 99 % (acidified-UV-NaClO) > 95 % (UV-PMS) > 90 % (UV-PDS) > 74 % (UV-H2O2) > 44 % (UV-NaClO) > 41 % (UV-NaClO2). Acidic pretreatment significantly boosts the reactivity of UV-NaClO. ESR combined with radical quenching tests reveals the radicals' generation and evolution, and their contribution rates to toluene conversion, i.e. ClO• > SO4•- > O2•- > 1O2 > â€¢OH. Theoretical calculations further unveil the ring-opening reaction routes and the nature of the activity difference of different radicals. The minimum energy required for ring-opening reaction is 116.77, 150.63, 168.29 and 191.92 kJ/mol with respect to ClO•, SO4•-, 1O2 and •OH, and finding that the ClO•-HO• pair is the best for toluene mineralization. The difficulty for eliminating typical VOCs by using UV-AOPs method is determined as toluene > chlorobenzene > benzene > ethyl acetate.

WTI, Brent or implied volatility index: Perspective of volatility spillover from oil market to Chinese stock market.

This study investigates the impact of oil market uncertainty on the volatility of Chinese sector indexes. We utilize commonly used realized volatility of WTI and Brent oil price along with the CBOE crude oil volatility index (OVX) to embody the oil market uncertainty. Based on the sample span from Mar 16, 2011 to Dec 31, 2019, this study utilizes vector autoregression (VAR) model to derive the impacts of the three different uncertainty indicators on Chinese stock volatilities. The empirical results show, for all sectors, the impact of OVX on sectors volatilities are more economically and statistically significant than that of realized volatility of both WTI and Brent oil prices, especially after the Chinese refined oil pricing reform of March 27, 2013. That implies OVX is more informative than traditional WTI and Brent oil prices with respect to volatility spillover from oil market to Chinese stock market. This study could provide some important implications for the participants in Chinese stock market.

Integrated genome-wide association and transcriptomic analysis to identify receptor kinase genes to stripe rust resistance in wheat germplasm from southwestern China.

Stripe rust of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat worldwide. Identification of new and elite Pst-resistance loci or genes has the potential to enhance overall resistance to this pathogen. Here, we conducted an integrated genome-wide association study (GWAS) and transcriptomic analysis to screen for loci associated with resistance to stripe rust in 335 accessions from Yunnan, including 311 landraces and 24 cultivars. Based on the environmental phenotype, we identified 113 protein kinases significantly associated with Pst resistance using mixed linear model (MLM) and generalized linear model (GLM) models. Transcriptomic analysis revealed that 52 of 113 protein kinases identified by GWAS were up and down regulated in response to Pst infection. Among these genes, a total of 15 receptor kinase genes were identified associated with Pst resistance. 11 candidate genes were newly discovered in Yunnan wheat germplasm. Our results revealed that resistance alleles to stripe rust were accumulated in Yunnan wheat germplasm, implying direct or indirect selection for improving stripe rust resistance in elite wheat breeding programs.

C-TERMINAL DOMAIN PHOSPHATASE-LIKE 3 contributes to GA-mediated growth and flowering by interaction with DELLA proteins.

Gibberellic acid (GA) plays a central role in many plant developmental processes and is crucial for crop improvement. DELLA proteins, the core suppressors in the GA signaling pathway, are degraded by GA via the 26S proteasomal pathway to release the GA response. However, little is known about the phosphorylation-mediated regulation of DELLA proteins. In this study, we combined GA response assays with protein-protein interaction analysis to infer the connection between Arabidopsis thaliana DELLAs and the C-TERMINAL DOMAIN PHOSPHATASE-LIKE 3 (CPL3), a phosphatase involved in the dephosphorylation of RNA polymerase II. We show that CPL3 directly interacts with DELLA proteins and promotes DELLA protein stability by inhibiting its degradation by the 26S proteasome. Consequently, CPL3 negatively modulates multiple GA-mediated processes of plant development, including hypocotyl elongation, flowering time, and anthocyanin accumulation. Taken together, our findings demonstrate that CPL3 serves as a novel regulator that could improve DELLA stability and thereby participate in GA signaling transduction.

Pretreatment CD8 + PD-1 + to CD4 + PD-1 + ratio is associated with the prognosis of advanced melanoma patients treated with PD-1 inhibitors.

The aim of this study was to determine whether the pretreatment CD8 + PD-1 + to CD4 + PD-1 + (PERLS) ratio is an independent risk prognostic factor of advanced melanoma patients. We retrospectively analyzed the efficacy and flow cytometry data from advanced melanoma patients who received PD-1 inhibitor as monotherapy between January 1, 2018 and January 26, 2022. Fifty-nine patients were enrolled, the PERLS cutoff was 1.125. PERLS did not correlate with clinical characteristics but were significantly associated with baseline CD8 + , CD4 + , and CD8 + PD-1 + T cells. The mean overall survival and the progression-free survival were 45.8 and 17.1 months for the low PERLS group (n = 39), compared with 29.9 ( P  = 0.001) and 9.7 ( P  = 0.003) months for the high PERLS group ( n  = 20), respectively. Pretreatment PERLS might contribute to selecting patients before receiving anti-PD-1 therapy.

Sensitivity improvement of subharmonic-based pressure measurement using phospholipid-coated monodisperse microbubbles.

The use of the subharmonic signal from microbubbles exposed to ultrasound is a promising safe and cost-effective approach for the non-invasive measurement of blood pressure. Achieving a high sensitivity of the subharmonic amplitude to the ambient overpressure is crucial for clinical applications. However, currently used microbubbles have a wide size distribution and diverse shell properties. This causes uncertainty in the response of the subharmonic amplitude to changes in ambient pressure, which limits the sensitivity. The aim of this study was to use monodisperse microbubbles to improve the sensitivity of subharmonic-based pressure measurements. With the same shell materials and gas core, we used a flow-focusing microfluidic chip and a mechanical agitation method to fabricate monodisperse (∼2.45-µm mean radius and 4.7 % polydisperse index) and polydisperse microbubbles (∼1.51-µm mean radius and 48.4 % polydisperse index), respectively. We varied the ultrasound parameters (i.e., the frequency, peak negative pressure (PNP) and pulse length), and found that there was an optimal excitation frequency (2.8 MHz) for achieving maximal subharmonic emission for monodisperse microbubbles, but not for polydisperse microbubbles. Three distinct regimes (occurrence, growth, and saturation) were identified in the response of the subharmonic amplitude to increasing PNP for both monodisperse and polydisperse microbubbles. For the polydisperse microbubbles, the subharmonic amplitude decreased either monotonically or non-monotonically with ambient overpressure, depending on the PNP. By contrast, for the monodisperse microbubbles, there was only a monotonic decrease at all PNPs. The maximum sensitivity (1.18 dB/kPa, R2 = 0.97) of the subharmonic amplitude to ambient overpressure for the monodisperse microbubbles was ∼6.5 times higher than that for the polydisperse microbubbles (0.18 dB/kPa, R2 = 0.88). These results show that monodisperse microbubbles can achieve a more consistent response of the subharmonic signal to changes in ambient overpressure and greatly improve the measurement sensitivity.

Memristor-based circuit design of episodic memory neural network and its application in hurricane category prediction.

Episodic memory, as a type of long-term memory (LTM), is used to learn and store the unique personal experience. Based on the episodic memory biological mechanism, this paper proposes a bionic episodic memory memristive neural network circuit. The proposed memristive neural network circuit includes a neocortical module, a parahippocampal module and a hippocampus module. The neocortical module with the two paths structure is used to receive the sensory signal, and is also used to separate and transmit the spatial information and the non-spatial information involved in the sensory signal. The parahippocampal module is composed of the parahippocampal cortex-MEA and the perirhinal cortex-LEA, which receives the two types of information from the neocortical module respectively. As the last module, the hippocampus module receives and integrates the output information of the parahippocampal module as well as generates the corresponding episodic memory. Meanwhile, the specific scenario information with the certain temporal signal from the generated episodic memory is also extracted by the hippocampus module. The simulation results in PSPICE show that the proposed memristive neural network circuit can generate the various episodic memories and extract the specific scenario information successfully. By configuring the memristor parameters, the proposed bionic episodic memory memristive neural network circuit can be applied to the hurricane category prediction, which verifies the feasibility of this work.