Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy

Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and is not fully understood.Intracellular calcium dynamics have been implicated in temporal lobe epilepsy.However,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice.In this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process.We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes.In particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures.Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠepisodes.In addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced.Intriguingly,it was possible to rescue the altered intracellular calcium dynamics.Via simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were improved.Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades.Furthermore,the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy,thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy.

Modulating perovskite crystallization and band alignment using coplanar molecules for high-performance indoor photovoltaics

The proper bandgap and exceptional photostability enable CsPbI_(3) as a potential candidate for indoor photovoltaics(IPVs),but indoor power conversion efficiency(PCE) is impeded by serious nonradiative recombination stemming from challenges in incomplete DMAPbI_(3) conversion and lattice structure distortion.Here,the coplanar symmetric structu re of hexyl sulfide(HS) is employed to functionalize the CsPbI_(3) layer for fabricating highly efficient IPVs.The hydrogen bond between HS and DMAI promotes the conversion of DMAPbI_(3) to CsPbI_(3),while the copianar symmetric structure enhances crystalline order.Simultaneously,surface sulfidation during HS-induced growth results in the in situ formation of PbS,spontaneously creating a CsPbI_(3) N-P homojunction to enhance band alignment and carrier mobility.As a result,the CsPbI_(3)&HS devices achieve an impressive indoor PCE of 39.90%(P_(in):334.6 μW cm^(-2),P_(out):133.5 μW cm^(-2)) under LED@2968 K,1062 lux,and maintain over 90% initial PCE for 800 h at ^(3)0% air ambient humidity.

Numerical Prediction of Ride Comfort of Tracked Vehicle Equipped with Novel Flexible Road Wheels

Enhancing ride comfort has always constituted a crucial focus in the design and research of modern tracked vehicles,heavily reliant on the driving system's performance.While the road wheel is a key component of the driving system,traditional road wheels predominantly adopt a solid structure,exhibiting subpar adhesion performance and damping effects,thereby falling short of meeting the demands for high-speed,stable,and long-distance driving in tracked vehicles.Addressing this issue,this paper proposes a novel type of flexible road wheel(FRW)characterized by a catenary construction.The study investigates the ride comfort of tracked vehicles equipped with flexible road wheels by integrating finite element and vehicle dynamic.First,three-dimensional(3D)finite element(FE)models of both flexible and rigid road wheels are established,considering material and contact nonlinearities.These models are validated through a wheel radial loading test.Based on the validated FE model,the paper uncovers the relationship between load and radial deformation of the road wheel,forming the basis for a nonlinear mathematical model.Subsequently,a half-car model of a tracked vehicle with seven degrees of freedom is established using Newton's second law.A random road model,considering the track effect and employing white noise,is constructed.The study concludes by examining the ride comfort of tracked vehicles equipped with flexible and rigid road wheels under various speeds and road grades.The results demonstrate that,in comparison to the rigid road wheel(RRW),the flexible road wheel enhances the ride comfort of tracked vehicles on randomly uneven roads.This research provides a theoretical foundation for the implementation of flexible road wheels in tracked vehicles.

Endowing low fatigue for elastocaloric effect by refined hierarchical microcomposite in additive manufactured NiTiCuCo alloy

NiTiCu-based shape memory alloys have been considered as ideal materials for solid-state refrigeration due to their superb cycling stability for elastocaloric effect.However,the embrittlement and deterioration caused by secondary phase and coarse grains restrict their applications,and it is still challenging since the geometric components are required.Here,bulk NiTiCuCo parts with excellent forming quality were fabricated by laser powder bed fusion(LPBF)technique.The as-fabricated alloy exhibits refined three-phases hierarchical microcomposite formed based on the rapid cooling mode of LPBF,composed of intricate dendritic Ti2Ni–NiTi composite and nano Ti2Cu embedded inside the NiTi-matrix.This configuration endows far superior elastocaloric stability compared to the as-cast counterpart.The low fatigue stems from the strong elastic coupling between the interphases with reversible martensite transformation,revealed by in-situ synchrotron high-energy x-ray diffraction.The fabrication of NiTiCuCo alloy via LPBF fills the bill of complex geometric structures for elastocaloric NiTiCu alloys.The understanding of interphase micro-coupling could provide the guide for designing LPBF fabricated shape memory-based composites,enabling their applications for special demands on other functionalities.

2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-Glucoside modulates CHEK2 and CCND1 alternative splicing to inhibit MCF-7 cells proliferation

Background:In our previous study,we observed a synergistic effect of 2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-glucoside combined with adriamycin to induce apoptosis in MCF-7 breast cancer cells.However,the underlying mechanisms of epigenetic modifications,such as alternative splicing,have not been explored.In this study,we aimed to investigate the mechanism by which THSG inhibits MCF-7 cell proliferation using full-length transcriptome sequencing.Methods:First,cell viability was examined using the methyl thiazolyl tetrazolium method and full-length transcriptome sequencing was performed to identify genes and pathways.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to identify the principal pathways and targets of THSG.Flow cytometry analysis of cell cycle distribution was performed.Meanwhile,the analysis of alternative splicing and domains of the key proteins was conducted.Quantitative polymerase chain reaction and western blotting were performed for verification.Results:THSG showed significant cytotoxic activity in MCF-7 cells.Full-length transcriptome sequencing revealed differential alternative splicing with 173 upregulated and 263 downregulated genes.Further analysis identified distinct differential expression of genes(CHEK2-211 and CCND1-201)involved in the cell cycle in the THSG-treated group.Subsequently,alternative splicing types of CHEK2(mutually exclusive exon)and CCND1(intron retention).We found that THSG downregulated mRNA expression,as confirmed by quantitative polymerase chain reaction analysis.Interestingly,protein structural analysis revealed that THSG treatment led to the generation of CHK2-211,which was the result of a mutation in the amino acid residues(GLU-150,ASN-151)of the CHEK2 domain(VAL-150,GLY-151).and CyclinD1-201 were obtained when an amino acid(ASP-267)in the domain was lost in CyclinD1.Moreover,molecular docking analysis demonstrated that the domains of key proteins could bind THSG more effectively,with no difference in affinity.Western blotting confirmed that THSG inhibited the expression of CHK2 and CyclinD1.Conclusion:THSG modulated the alternative splicing of CHEK2 and CCND1 by inducing G0/G1 cell cycle arrest,consequently suppressing MCF-7 cell proliferation.

Impact of different anastomosis methods on post-recurrence after intestinal resection for Crohn's disease:A meta-analysis

BACKGROUND Crohn's disease(CD)is a chronic inflammatory disease of the gastrointestinal tract,often requiring intestinal resection as a common treatment.However,recurrence after surgery is common.The anastomotic configuration after bowel resection appears to be associated with the recurrence of CD.Previous studies have suggested that the Kono-S anastomosis may help to reduce the recurrence rate.However,the results remain controversial.Therefore,evidence-based evidence is needed to prove the advantages of Kono-S anastomosis.AIM To measure the influence of anastomosis techniques on the long-term relapse rate of CD by conducting a meta-analysis.METHODS PubMed,Scopus,and Cochrane Library were searched until October 8,2023.Patients who underwent intestinal resection due to CD were included.The intervention measures included Kono-S anastomosis,whereas the control group received traditional anastomosis such as end-to-end,end-to-side,and side-to-side anastomosis.Only randomized clinical trials and observational studies were included.The primary outcome measures were hospital stay post-surgery,overall postoperative complication incidence,the proportion of Clavien-Dindo grade IIIa or higher,overall postoperative recurrence rate,and Rutgeerts score.RESULTS From 2011 to 2023,six articles met the inclusion and exclusion criteria.The results indicated that Kono-S anastomosis can reduce the hospital stay post-surgery of patients with CD[MD=-0.26,95%CI:-0.42 to-0.10,P=0.002]than other traditional anastomosis methods.Compared to other traditional anastomosis methods,Kono-S anastomosis can significantly reduce the total recurrence rate[MD=0.40,95%CI:0.17 to 0.98,P=0.05]and postoperative Rutgeerts score[MD=-0.81,95%CI:-0.96 to-0.66,P<0.001]in patients with CD.However,there is no significant disparity in the overall occurrence of postoperative complications and the proportion of Clavien-Dindo≥IIIa.CONCLUSION Kono-S anastomosis has the potential to expedite the recuperation of CD and diminish relapse hazards;however,additional larger trials are necessary to authenticate its effectiveness.

Microglia and astrocytes mediate synapse engulfment in a MER tyrosine kinase-dependent manner after traumatic brain injury

Recent studies have shown that microglia/macrophages and astrocytes can mediate synaptic phagocytosis through the MER proto-oncokinase in developmental or stroke models,but it is unclear whether the same mechanism is also active in traumatic brain injury.In this study,we established a mouse model of traumatic brain injury and found that both microglia/macrophages and astrocytes phagocytosed synapses and expression of the MER proto-oncokinase increased 14 days after injury.Specific knockout of MER in microglia/macrophages or astrocytes markedly reduced injury volume and greatly improved neurobehavioral function.In addition,in both microglia/macrophages-specific and astrocytes-specific MER knock-out mice,the number of microglia/macrophage and astrocyte phagocytosing synapses was markedly decreased,and the total number of dendritic spines was increased.Our study suggested that MER proto-oncokinase expression in microglia/macrophages and astrocytes may play an important role in synaptic phagocytosis,and inhibiting this process could be a new strategy for treating traumatic brain injury.

Insights into cryptic speciation of quillworts in China

Cryptic species are commonly misidentified because of high morphological similarities to other species.One group of plants that may harbor large numbers of cryptic species is the quillworts(Isoetes spp.),an ancient aquatic plant lineage.Although over 350 species of Isoetes have been reported globally,only ten species have been recorded in China.The aim of this study is to better understand Isoetes species diversity in China.For this purpose,we systematically explored the phylogeny and evolution of Isoetes using complete chloroplast genome(plastome)data,spore morphology,chromosome number,genetic structure,and haplotypes of almost all Chinese Isoetes populations.We identified three ploidy levels of Isoetes in Chinaddiploid(2n=22),tetraploid(2n=44),and hexaploid(2n=66).We also found four megaspore and microspore ornamentation types in diploids,six in tetraploids,and three in hexaploids.Phylogenetic analyses confirmed that I.hypsophila as the ancestral group of the genus and revealed that Isoetes diploids,tetraploids,and hexaploids do not form monophyletic clades.Most individual species possess a single genetic structure;however,several samples have conflicting positions on the phylogenetic tree based on SNPs and the tree based on plastome data.All 36 samples shared 22 haplotypes.Divergence time analysis showed that I.hypsophila diverged in the early Eocene(~48.05 Ma),and most other Isoetes species diverged 3-20 Ma.Additionally,different species of Isoetes were found to inhabit different water systems and environments along the Yangtze River.These findings provide new insights into the relationships among Isoetes species in China,where highly similar morphologic populations may harbor many cryptic species.

Anti-bacterial mechanism of baicalin-tobramycin combination on carbapenem-resistant Pseudomonas aeruginosa

BACKGROUND Pseudomonas aeruginosa(P.aeruginosa)is an important cause of nosocomial infections,and contributes to high morbidity and mortality,especially in intensive care units.P.aeruginosa is considered a'critical'category bacterial pathogen by the World Health Organization to encourage an urgent need for research and development of new antibiotics against its infections.AIM To investigate the effectiveness of baicalin combined with tobramycin therapy as a potential treatment method for carbapenem-resistant P.aeruginosa(CRPA)infections.METHODS Polymerase chain reaction(PCR)and RT-PCR were used to detect the expression levels of drug-resistant genes(including VIM,IMP and OprD2)and biofilmrelated genes(including algD,pslA and lasR)in CRPA that confer resistance to tobramycin,baicalin and tobramycin combined with baicalin(0,1/8,1/4,1/2 and 1MIC).RESULTS There was a correlation between biofilm formation and the expression of biofilmrelated genes.In addition,VIM,IMP,OprD2,algD,pslA and lasR that confer biofilm production under different concentrations in CRPA were significantly correlated.The synergistic effect of baicalin combined with tobramycin was a significant down-regulation of VIM,IMP,algD,pslA and lasR.CONCLUSION Baicalin combined with tobramycin therapy can be an effective treatment method for patients with CRPA infection.

Stitching Perovskite Grains with Perhydropoly(Silazane)Anti-Template-Agent for High-Efficiency and Stable Solar Cells Fabricated in Ambient Air

All inorganic CsPbI_(3)perovskite solar cells(PSCs)have emerged as disruptive photovoltaic technology owing to their admirable photoelectric properties and the non-volatile active layer.However,the phase instability against moisture severely limits the fabrication environment for the high-efficiency devices,breaking through the confinement region to achieve scalable manufacturing has been the primary issue for future commercialization.Here,we develop a curing-anti-solvent strategy for fabricating high-quality and stable black-phase CsPbI_(3)perovskite films in ambient air by introducing an inorganic polymer perhydropolysilazane(PHPS)into methyl acetate to form anti-template agent.The cross-linked PHPS reduces moisture erosions while the hydrolyzate silanol network(–Si(OH)_(4)^(–))controls the perovskite crystal growth by forming Lewis adducts with PbI_(2)during the fabrication.The polycondensation adduct of Si–O–Si/Si–O–Pb strongly binds to CsPbI_(3)grains as a shield layer to hamper phase transition.Using the inorganic CsPbI_(3)perovskite thin-film with PHPS-modified anti-solvent processing as the light absorber,the n–i–p planar solar cell achieved an efficiency of 19.17%under standard illumination test conditions.More importantly,the devices showed excellent moisture stability,retaining about 90%of the initial efficiency after 1000 h under 30%RH.

新时期高校图书馆古籍保护对策研究

近年来,高校图书馆作为我国古籍保护的重要力量,在古籍原生性和再生性保护方面取得了较大的成绩。但与此同时,古籍保护复合型人才缺乏、数字化整体水平不高、传承性保护不够深入等问题也日益突显。从新时期高校图书馆古籍保护工作面临的挑战入手,提出结合高校自身特点解决问题的对策,以期对古籍保护工作的进一步发展有所裨益。

RhoA/ROCK pathway regulates hypoxia-induced myocardial cell apoptosis

Objective:To observe the regulatory effects of RhoA/ROCK pathway on the apoptosis of cardiac myocyte induced by anoxia and its mechanism.Methods:The model of cardiac myocyte anoxia was established.The beat pulsations and apoptosis rales after 1 h,3 h,6 h,9 h and 12 h of anoxia were recorded and the expressions of RhoA,ROCK1/2,p-PI3 K,p-AKT and caspae-3 were detected,too.The apoptosis and the expressions of related proteins were detected after RNAi of RhoA and the inhibition of ROCK by Y-27632.Results:The beat pulsations after 1 h,3 h,6 h.9h and 12 h decreased gradually but the apoptosis rates increased gradually,and the expressions of RhoA,ROCK1/2,p-P13 K,p-AKT and caspase-3 were increasing along with the increasing duration of anoxia.The apoptotic rales after 1 h,3 h,6 h.9 h and 12 h of anoxia were(4.36±0.98)%,(8.36±2.12)%,(15.32±3.62)%,(18.68±4.83)%and(24.56±6.22)%.respectively and decreased more significantly than control group in different time points of anoxia(P<0.05).and the expressions of RhoA,ROCK1/2,p-PI3 K,p-AKT and caspase-3 decreased significantly(P<0.05).The apoptosis rate and the expressions of RhoA,ROCK1/2,p-PI3 K,p-AKT and caspase-3 decreased significantly(P<0.05) after the inhibition of ROCK by Y-27632(P<0.05).Conclusions:RhoA/ROCK pathway plays a critical role in the regulation of the apoptosis of cardiac myocyte induced by anoxia,which may be accompanied by regulating the activity of PI3K/AKT/Caspase-3 pathway.

Probiotic BIFICO cocktail ameliorates Helicobacter pylori induced gastritis

AIM: To determine the protective effect of triple viable probiotics on gastritis induced by Helicobacter pylori (H. pylori) and elucidate the possible mechanisms of protection. METHODS: Colonization of BIFICO strains in the mouse stomach was determined by counting colony-forming units per gram of stomach tissue. After treatment with or without BIFICO, inflammation and H. pylori colonization in the mouse stomach were analyzed by hematoxylin and eosin and Giemsa staining, respectively. Cytokine levels were determined by enzyme-linked immunosorbent assay and Milliplex. The activation of nuclear factor (NF)-kappa B and MAPK signaling in human gastric epithelial cells was evaluated by Western blot analysis. Quantitative reverse transcription-polymerase chain reaction was used to quantify TLR2, TLR4 and MyD88 mRNA expression in the mouse stomach. RESULTS: We demonstrated that BIFICO, which contains a mixture of Enterococcus faecalis, Bifido-bacterium longum and Lactobacillus acidophilus, was tolerant to the mouse stomach environment and was able to survive both the 8-h and 3-d courses of administration. Although BIFICO treatment had no effect on the colonization of H. pylori in the mouse stomach, it ameliorated H. pylori -induced gastritis by significantly inhibiting the expression of cytokines and chemokines such as TNF-alpha, IL-1 beta, IL-10, IL-6, G-CSF and MIP-2 (P < 0.05). These results led us to hypothesize that BIFICO treatment would diminish the H. pylori-induced inflammatory response in gastric mucosal epithelial cells in vitro via the NF-kappa B and MAPK signaling pathways. Indeed, we observed a decrease in the expression of the NF-kappa B subunit p65 and in the phosphorylation of I kappa B-alpha, ERK and p38. Moreover, there was a significant decrease in the production of IL-8, TNF-alpha, G-CSF and GM-CSF (P < 0.05), and the increased expression of TLR2, TLR4 and MyD88 induced by H. pylori in the stomach was also significantly reduced following BIFICO treatment (P < 0.05). CONCLUSION: Our results suggest that the probiotic cocktail BIFICO can ameliorate H. pylori-induced gastritis by inhibiting the inflammatory response in gastric epithelial cells.

Genome size evolution of the extant lycophytes and ferns

Ferns and lycophytes have remarkably large genomes.However,little is known about how their genome size evolved in fern lineages.To explore the origins and evolution of chromosome numbers and genome size in ferns,we used flow cytometry to measure the genomes of 240 species(255 samples)of extant ferns and lycophytes comprising 27 families and 72 genera,of which 228 species(242 samples)represent new reports.We analyzed correlations among genome size,spore size,chromosomal features,phylogeny,and habitat type preference within a phylogenetic framework.We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size.Using the phylogeny,we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference.We found that 2 C values had weak phylogenetic signal,whereas the base number of chromosomes(x)had a strong phylogenetic signal.Furthermore,our analyses revealed a positive correlation between genome size and chromosome traits,indicating that the base number of chromosomes(x),chromosome size,and polyploidization may be primary contributors to genome expansion in ferns and lycophytes.Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types;specifically,multinomial logistic regression indicated that species with larger 2 C values were more likely to be epiphytes.Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes,whereas transitions to other habitat types occurred as the major clades emerged.Shifts in habitat types appear be followed by periods of genomic stability.Based on these results,we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.

Biological mechanism study of meditation and its application in mental disorders

In recent years,research on meditation as an important alternative therapy has developed rapidly and been widely applied in clinical medicine.Mechanism studies of meditation have also developed progressively,showing that meditation has great impact on brain structure and function,and epigenetic and telomere regulation.In line with this,the application of meditation has gradually been expanded to mental illness,most often applied for major depressive disorders and substance-related and addictive disorders.The focus of this paper is to illustrate the biological mechanisms of meditation and its application in mental disorders.

Expression of netrin-1 and its receptors, deleted in colorectal cancer and uncoordinated locomotion-5 homolog B, in rat brain following focal cerebral ischemia reperfusion injury

Netrin-1 is currently one of the most highly studied axon guidance factors. Netrin-1 is widely expressed in the embryonic central nervous system, and together with the deleted in colorectal cancer and uncoordinated locomotion-5 homolog B receptors, netrin-1 plays a guiding role in the construction of neural conduction pathways and the directional migration of neuronal cells. In this study, we established a rat middle cerebral artery ischemia reperfusion model using the intraluminal thread technique. Immunofluorescence microscopy showed that the expression of netrin-1 and deleted in colorectal cancer in the ischemic penumbra was upregulated at 1 day after reperfusion, reached a peak at 14 days, and decreased at 21 days. There was no obvious change in the expression of uncoordinated locomotion-5 homolog B during this time period. Double immunofluorescence labeling revealed that netrin-1 was expressed in neuronal cells and around small vessels, but not in astrocytes and microglia, while deleted in colorectal cancer was localized in the cell membranes and protrusions of neurons and astrocytes. Our experimental findings indicate that netrin-1 may be involved in post-ischemic repair and neuronal protection via deleted in colorectal cancer receptors.

Lycophyte transcriptomes reveal two whole-genome duplications in Lycopodiaceae:Insights into the polyploidization of Phlegmariurus

Lycophytes are an ancient clade of the non-flowering vascular plants with chromosome numbers that vary from tens to hundreds.They are an excellent study system for examining whole-genome duplications(WGDs),or polyploidization,in spore-dispersed vascular plants.However,a lack of genome sequence data limits the reliable detection of very ancient WGDs,small-scale duplications(SSDs),and recent WGDs.Here,we integrated phylogenomic analysis and the distribution of synonymous substitutions per synonymous sites(Ks)of the transcriptomes of 13 species of lycophytes to identify,locate,and date multiple WGDs in the lycophyte family Lycopodiaceae.Additionally,we examined the genus Phlegmariurus for signs of genetic discordance,which can provide valuable insight into the underlying causes of such conflict(e.g.,hybridization,incomplete lineage sorting,or horizontal gene transfer).We found strong evidence that two WGD events occurred along the phylogenetic backbone of Lycopodiaceae,with one occurring in the common ancestor of extant Phlegmariurus(Lycopodiaceae)approximately 22-23 million years ago(Mya)and the other occurring in the common ancestor of Lycopodiaceae around 206-214 Mya.Interestingly,we found significant genetic discordance in the genus Phlegmariurus,indicating that the genus has a complex evolutionary history.This study provides molecular evidence for multiple WGDs in Lycopodiaceae and offers phylogenetic clues to the evolutionary history of Lycopodiaceae.

Rapid decrease in Antarctic sea ice in recent years

A 41-year Antarctic sea ice concentration(SIC)dataset derived from satellite passive microwave radiometers during the period of 1979–2019 has been used to analyze sea ice changes in recent decades.The trends of SIC and sea ice extent(SIE)are calculated during the periods of 1979–2019,1979–2013,and 2014–2019.The trends show regionally dependent features.The SIC shows an increasing trend in most of the regions except the Bellingshausen Sea and Amundsen Sea(BA)during 1979–2019 and 1979–2013.The SIE trend shows a decreasing or decelerating trend in the period of 1979–2019((6835±2210)km^(2)/a)compared with the 1979–2013 period((18600±2203)km^(2)/a).In recent years(2014–2019),the SIC and SIE have exhibited decreasing trends(–(34567±3521)km^(2)/month),especially in the Weddell Sea(WS)and Ross Sea(RS)during summer and autumn.The trends are related to regionally dependent causes.The analyses show that the SIC and SIE decreased in response to the warming trend of 2 m air temperature(T_(a-2m))and have exhibited a good relationship with T_(a-2m) in summer and autumn in recent years.The sea ice decrease in the Antarctic is mainly caused by increases in absorbed energy and southward energy transportation in recent years,such as the increase in gained solar radiation and moist static energy from the south,which demonstrate notable regional characteristics.In the WS region,the local positive feedback from the additional absorbed solar radiation,resulting in warmer air and reduced sea ice,is the main reason for the sea ice decrease in recent years.The increase in southward energy transport has also favored a decrease in sea ice.In the RS region,the increase in southward-transported moist static energy has contributed to the decrease in sea ice,and the increases in cloud cover and longwave radiation have prevented sea ice growth.

FPGA implementation and image encryption application of a new PRNG based on a memristive Hopfield neural network with a special activation gradient

A memristive Hopfield neural network(MHNN)with a special activation gradient is proposed by adding a suitable memristor to the Hopfield neural network(HNN)with a special activation gradient.The MHNN is simulated and dynamically analyzed,and implemented on FPGA.Then,a new pseudo-random number generator(PRNG)based on MHNN is proposed.The post-processing unit of the PRNG is composed of nonlinear post-processor and XOR calculator,which effectively ensures the randomness of PRNG.The experiments in this paper comply with the IEEE 754-1985 high precision32-bit floating point standard and are done on the Vivado design tool using a Xilinx XC7 Z020 CLG400-2 FPGA chip and the Verilog-HDL hardware programming language.The random sequence generated by the PRNG proposed in this paper has passed the NIST SP800-22 test suite and security analysis,proving its randomness and high performance.Finally,an image encryption system based on PRNG is proposed and implemented on FPGA,which proves the value of the image encryption system in the field of data encryption connected to the Internet of Things(Io T).

Modelling the annual cycle of landfast ice near Zhongshan Station,East Antarctica

A high resolution one-dimensional thermodynamic snow and ice(HIGHTSI)model was used to model the annual cycle of landfast ice mass and heat balance near Zhongshan Station,East Antarctica.The model was forced and initialized by meteorological and sea ice in situ observations from April 2015 to April 2016.HIGHTSI produced a reasonable snow and ice evolution in the validation experiments,with a negligible mean ice thickness bias of(0.003±0.06)m compared to in situ observations.To further examine the impact of different snow conditions on annual evolution of first-year ice(FYI),four sensitivity experiments with different precipitation schemes(0,half,normal,and double)were performed.The results showed that compared to the snow-free case,the insulation effect of snow cover decreased bottom freezing in the winter,leading to 15%–26%reduction of maximum ice thickness.Thick snow cover caused negative freeboard and flooding,and then snow ice formation,which contributed 12%–49%to the maximum ice thickness.In early summer,snow cover delayed the onset of ice melting for about one month,while the melting of snow cover led to the formation of superimposed ice,accounting for 5%–10%of the ice thickness.Internal ice melting was a significant contributor in summer whether snow cover existed or not,accounting for 35%–56%of the total summer ice loss.The multi-year ice(MYI)simulations suggested that when snow-covered ice persisted from FYI to the 10th MYI,winter congelation ice percentage decreased from 80%to 44%(snow ice and superimposed ice increased),while the contribution of internal ice melting in the summer decreased from 45%to 5%(bottom ice melting dominated).