BSTFNet:An Encrypted Malicious Traffic Classification Method Integrating Global Semantic and Spatiotemporal Features

While encryption technology safeguards the security of network communications,malicious traffic also uses encryption protocols to obscure its malicious behavior.To address the issues of traditional machine learning methods relying on expert experience and the insufficient representation capabilities of existing deep learning methods for encrypted malicious traffic,we propose an encrypted malicious traffic classification method that integrates global semantic features with local spatiotemporal features,called BERT-based Spatio-Temporal Features Network(BSTFNet).At the packet-level granularity,the model captures the global semantic features of packets through the attention mechanism of the Bidirectional Encoder Representations from Transformers(BERT)model.At the byte-level granularity,we initially employ the Bidirectional Gated Recurrent Unit(BiGRU)model to extract temporal features from bytes,followed by the utilization of the Text Convolutional Neural Network(TextCNN)model with multi-sized convolution kernels to extract local multi-receptive field spatial features.The fusion of features from both granularities serves as the ultimate multidimensional representation of malicious traffic.Our approach achieves accuracy and F1-score of 99.39%and 99.40%,respectively,on the publicly available USTC-TFC2016 dataset,and effectively reduces sample confusion within the Neris and Virut categories.The experimental results demonstrate that our method has outstanding representation and classification capabilities for encrypted malicious traffic.

Adaptive target and jamming recognition for the pulse doppler radar fuze based on a time-frequency joint feature and an online-updated naive bayesian classifier with minimal risk

This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are analyzed.Then,the frequency entropy and peak-to-peak ratio are extracted from the matched filter output of the PDRF,and the time-frequency joint feature is constructed.Based on the time-frequency joint feature,the naive Bayesian classifier(NBC)with minimal risk is established for target and jamming recognition.To improve the adaptability of the proposed method in complex environments,an online update process that adaptively modifies the classifier in the duration of the work of the PDRF is proposed.The experiments show that the PDRF can maintain high recognition accuracy when the signal-to-noise ratio(SNR)decreases and the jamming-to-signal ratio(JSR)increases.Moreover,the applicable analysis shows that he ONBCMR method has low computational complexity and can fully meet the real-time requirements of PDRF.

Monodispersed ultrathin twisty PdBi alloys nanowires assemblies with tensile strain enhance C_(2+)alcohols electrooxidation

Direct alcohol fuel cells(DAFCs)are powered by the alcohol electro-oxidation reaction(AOR),where an electrocatalyst with an optimal electronic structure can accelerate the sluggish AOR.Interestingly,strain engineering in hetero-catalysis offers a promising route to boost their catalytic activity.Herein,we report on a class of monodispersed ultrathin twisty PdBi alloy nanowires(TNWs)assemblies with face-centered structures that drive AORs.These thin nanowire structures expose a large number of reactive sites.Strikingly,Pd_(6)Bi_(1)TNWs show an excellent current density of 2066,3047,and 1231 mA mg_(Pd)^(-1)for oxidation of ethanol,ethylene glycol,and glycerol,respectively.The“volcano-like”behaviors observed on PdBi TNWs for AORs indicate that the maximum catalytic mass activity is a well balance between active intermediates and blocking species at the interface.This study offers an effective and universal method to build novel nanocatalysts in various applications by rationally designing highly efficient catalysts with specific strain.

The Effect of Lateral Offset Distance on the Aerodynamics and Fuel Economy of Vehicle Queues

The vehicle industry is always in search of breakthrough energy-saving and emission-reduction technologies.In recent years,vehicle intelligence has progressed considerably,and researchers are currently trying to take advantage of these developments.Here we consider the case of many vehicles forming a queue,i.e.,vehicles traveling at a predetermined speed and distance apart.While the majority of existing studies on this subject have focused on the influence of the longitudinal vehicle spacing,vehicle speed,and the number of vehicles on aerodynamic drag and fuel economy,this study considers the lateral offset distance of the vehicle queue.The group fuel consumption savings rate is calculated and analyzed.As also demonstrated by experimental results,some aerodynamic benefits exist.Moreover,the fuel consumption saving rate of the vehicle queue decreases as the lateral offset distance increases.

Blind parameter estimation of pseudo-random binary code-linear frequency modulation signal based on Duffing oscillator at low SNR

Conventional parameter estimation methods for pseudo-random binary code-linear frequency modulation(PRBC-LFM)signals require prior knowledge,are computationally complex,and exhibit poor performance at low signal-to-noise ratios(SNRs).To overcome these problems,a blind parameter estimation method based on a Duffing oscillator array is proposed.A new relationship formula among the state of the Duffing oscillator,the pseudo-random sequence of the PRBC-LFM signal,and the frequency difference between the PRBC-LFM signal and the periodic driving force signal of the Duffing oscillator is derived,providing the theoretical basis for blind parameter estimation.Methods based on amplitude method,short-time Fourier transform method,and power spectrum entropy method are used to binarize the output of the Duffing oscillator array,and their performance is compared.The pseudo-random sequence is estimated using Duffing oscillator array synchronization,and the carrier frequency parameters are obtained by the relational expressions and characteristics of the difference frequency.Simulation results show that this blind estimation method overcomes limitations in prior knowledge and maintains good parameter estimation performance up to an SNR of-35 dB.

Leptin promotes proliferation and invasion of osteosarcoma cells by upregulating the expression of SIRT1

Osteosarcoma(OS)is a primary high-grade malignant bone neoplasm,and the prognosis ofOS remains poor due to early metastasis.Leptin plays an essential role in tumorigenesis,but the role of leptin in the development of OS is still not fully understood.In this study,we used a human osteosarcomaMG-63 cell line as an experimentalmodel.MG-63 cells were treated with leptin,and cell proliferation,apoptosis,adhesion,invasion,and gene expression,were evaluated.The results showed that leptin promoted proliferation,decreased adhesion,suppressed apoptosis,and promoted invasion,of MG-63 cells.Moreover,the expression of SIRT1 was upregulated in MG-63 cells exposed to leptin.Furthermore,MMP-2,8,and 9 were significantly upregulated by SIRT1,while SIRT1 knockdown inhibited the proliferation and invasion of MG-63 cells.In conclusion,our results suggest that leptin promotes OS cell proliferation and invasion by inducing the expression of SIRT1.

Dynamic changes in butyrate levels regulate satellite cell homeostasis by preventing spontaneous activation during aging

The gut microbiota plays a pivotal role in systemic metabolic processes and in particular functions,such as developing and preserving the skeletal muscle system.However,the interplay between gut microbiota/metabolites and the regulation of satellite cell(SC)homeostasis,particularly during aging,remains elusive.We propose that gut microbiota and its metabolites modulate SC physiology and homeostasis throughout skeletal muscle development,regeneration,and aging process.Our investigation reveals that microbial dysbiosis manipulated by either antibiotic treatment or fecal microbiota transplantation from aged to adult mice,leads to the activation of SCs or a significant reduction in the total number.Furthermore,employing multi-omics(e.g.,RNA-seq,16S r RNA gene sequencing,and metabolomics)and bioinformatic analysis,we demonstrate that the reduced butyrate levels,alongside the gut microbial dysbiosis,could be the primary factor contributing to the reduction in the number of SCs and subsequent impairments during skeletal muscle aging.Meanwhile,butyrate supplementation can mitigate the antibiotics-induced SC activation irrespective of gut microbiota,potentially by inhibiting the proliferation and differentiation of SCs/myoblasts.The butyrate effect is likely facilitated through the monocarboxylate transporter 1(Mct1),a lactate transporter enriched on membranes of SCs and myoblasts.As a result,butyrate could serve as an alternative strategy to enhance SC homeostasis and function during skeletal muscle aging.Our findings shed light on the potential application of microbial metabolites in maintaining SC homeostasis and preventing skeletal muscle aging.

The importance of Righi-Leduc heat flux to the ablative Rayleigh-Taylor instability during a laser irradiating targets

The Righi±Leduc heat flux generated by the self-generated magnetic field in the ablative Rayleigh±Taylor instability driven by a laser irradiating thin targets is studied through two-dimensional extended-magnetohydrodynamic simulations.The perturbation structure gets into a low magnetization state though the peak strength of the self-generated magnetic field could reach hundreds of teslas.The Righi±Leduc effect plays an essential impact both in the linear and nonlinear stages,and it deflects the total heat flux towards the spike base.Compared to the case without the self-generated magnetic field included,less heat flux is concentrated at the spike tip,finally mitigating the ablative stabilization and leading to an increase in the velocity of the spike tip.It is shown that the linear growth rate is increased by about 10%and the amplitude during the nonlinear stage is increased by even more than 10%due to the feedback of the magnetic field,respectively.Our results reveal the importance of Righi±Leduc heat flux to the growth of the instability and promote deep understanding of the instability evolution together with the self-generated magnetic field,especially during the acceleration stage in inertial confinement fusion.

丹参酮ⅡA磺酸钠对血管紧张素Ⅱ诱导的大鼠心肌纤维化的影响

目的观察丹参酮ⅡA磺酸钠(STS)对血管紧张素Ⅱ(AngⅡ)诱导的大鼠心肌纤维化的影响;并初步探讨STS抗心肌纤维化的作用与转录因子NF-E2相关因子2(Nrf2)所调控的抗氧化应激反应的关系。方法 40只SD大鼠随机分为5组(对照组,模型组,低、中、高剂量STS组),采用皮下植入微量渗透泵缓释AngⅡ复制大鼠心肌纤维化模型,各STS组给予不同剂量STS处理。3周后,采用苏木精伊红和马松染色法观察心肌纤维化程度;采用qRT-PCR和Western blot检测心肌组织中Ⅰ、Ⅲ型胶原,Nrf2和它的胞质接头蛋白Keap1,以及Nrf2所调控的抗氧化酶和Ⅱ相解毒酶mRNA水平及其蛋白水平;采用比色法检测心肌组织中丙二醛、谷胱甘肽水平及超氧化物歧化酶活性。结果 STS呈剂量依赖性地减轻AngⅡ诱导的心肌纤维化,促使Nrf2在细胞核内的聚集,提高抗氧化酶及Ⅱ相解毒酶的表达,增强抗氧化应激反应,降低心肌组织脂质过氧化水平。结论 STS能够有效减轻AngⅡ诱导的大鼠心肌纤维化,其抗纤维化作用与调控Nrf2信号通路相关。

木粉尘职业接触极限值的研究

木头作为原材料得到广泛应用 ,但硬木粉尘 (如橡木和山毛榉粉尘 )可导致人患鼻癌。不同国家的木粉尘的职业接触极限值 (或极限值 )却不尽相同。虽然关于木粉尘的极限值的国际讨论持续已久 ,但仍缺乏更好支持其极限值推导的健康相关数据。为保护木材加工工人的身体健康以及给木粉尘的职业接触极限值的制定机构提供可靠数据和科学决策方面的建议 ,笔者针对怎样为木粉尘 ,特别是致癌木粉尘制定一个合理极限值的问题 ,在“比较”和“设定”两方面对国际范围内的木粉尘的极限值进行了研究 ,其结果表明 ,大部分国家给予软木粉尘和硬木粉尘的极限值分别为 5mg/m3 和 1mg/m3 ;提出利用剂量 -影响 -关系和“线性多阶段”方法也可以给致癌硬木粉尘建立一个健康基础极限值或者一个可接受极限值 ,其极限值应该不仅根据木材类型而且还需根据工作岗位而分别综合设定。

肿瘤电场治疗仪治疗复发脑胶质母细胞瘤的前瞻性单中心单臂探索性研究

目的:评价肿瘤电场治疗仪用于治疗复发胶质母细胞瘤患者的初步安全性和有效性。方法:选取2020年4月至2020年8月期间中南大学湘雅医院和解放军总医院6例受试者,均为男性,中位年龄53(48~68)岁。入组复发胶质母细胞瘤受试者并收集临床资料,通过观察受试者治疗期间不良事件的发生率、肿瘤进展时间(time to progression,TTP)和总生存时间(overall survival,OS)评估治疗的安全性和有效性。结果:入组6例受试者中位随访时间10.9(8.4~22.7)个月,所有受试者发生肿瘤进展,5例随访至死亡,截至随访截止1例生存。中位肿瘤进展时间(median time to progression,m TTP)为4.7个月(95%CI:3.62~5.78),中位无进展生存时间(median progression-free survival,mPFS)为4.7个月(95%CI:3.62~5.78),中位总生存时间(median overall survival,mOS)为10.9个月(95%CI:8.86~12.94)。客观缓解率(CR+PR)33.3%;疾病控制率(SD+PR+CR)83.3%。治疗相关的不良事件主要为头皮皮疹,发生率为66.7%,经调整电极片黏贴位置、保持创口干燥、涂抹类固醇类软膏或抗生素软膏后均可有效缓解。结论:肿瘤电场治疗仪用于治疗复发胶质母细胞瘤的受试者在电场治疗过程中呈现良好的初步安全性和有效性。

Generation of tryptophan hydroxylase 2 gene knockout pigs by CRISPR/Cas9-mediated gene targeting

Unbalanced brain serotonin(5-HT) levels have implications in various behavioral abnormalities and neuropsychiatric disorders. The biosynthesis of neuronal 5-HT is regulated by the rate-limiting enzyme, tryptophan hydroxylase-2(TPH2). In the present study, the clustered regularly interspaced short palindromic repeat(CRISPR)/CRISPR-associated(Cas) system was used to target the Tph2 gene in Bama mini pig fetal fibroblasts. It was found that CRISPR/Cas9 targeting efficiency could be as high as 61.5%, and the biallelic mutation efficiency reached at38.5%. The biallelic modified colonies were used as donors for somatic cell nuclear transfer(SCNT) and 10 Tph2 targeted piglets were successfully generated. These Tph2 KO piglets were viable and appeared normal at the birth.However, their central 5-HT levels were dramatically reduced, and their survival and growth rates were impaired before weaning. These Tph2 KO pigs are valuable large-animal models for studies of 5-HT deficiency induced behavior abnomality.

Structural insights into a dual-specificity histone demethylase ceKDM7A from Caenorhabditis elegans

Histone lysine methylation can be removed by JmjC domain-containing proteins in a sequence- and methylationstate-specific manner. However, how substrate specificity is determined and how the enzymes are regulated were largely unknown. We recently found that ceKDM7A, a PHD- and JmjC domain-containing protein, is a histone demethylase specific for H3K9me2 and H3K27me2, and the PHD finger binding to H3K4me3 guides the demethylation activity in vivo. To provide structural insight into the molecular mechanisms for the enzymatic activity and the function of the PHD finger, we solved six crystal structures of the enzyme in apo form and in complex with single or two peptides containing various combinations of H3K4me3, H3K9me2, and H3K27me2 modifications. The structures indicate that H3Kgme2 and H3K27me2 interact with ceKDMTA in a similar fashion, and that the peptide-binding specificity is determined by a network of specific interactions. The geometrical measurement of the structures also revealed that H3K4me3 associated with the PHD finger and H3K9me2 bound to the JmjC domain are from two separate molecules, suggesting a trans-histone peptide-binding mechanism. Thus, our systemic structural studies reveal not only the substrate recognition by the catalytic domain but also more importantly, the molecular mechanism of dual specifieity of ceDKM7A for both H3K9me2 and H3K27me2.

Protective effects of medical ozone combined with traditional Chinese medicine against chemically-induced hepatic injury in dogs

AIM： To investigate the protective effect of medical ozone （O3） combined with Traditional Chinese Medicine （TCM） Yigan Fuzheng Paidu Capsules （YC） against carbon tetrachloride （CCh）-induced hepatic injury in dogs. METHODS： Thirty healthy dogs were divided randomly into five groups （n = 6 in each group）, namely control, oleanolic acid tablet （OAT）, O3, YC and O3 ＋ YC, given either no particular pre-treatment, oral OAT, medical ozone rectal insulfflation every other day, oral YC, or oral YC plus medical ozone rectal insulfflation every other day, respectively, for 30 consecutive days. After pre-treatment, acute hepatic injury was induced in all dogs with a single-dose intraperitoneal injection of CCh. General condition and survival time were recorded. The biochemical and hematological indexes of alanine aminotransferase （ALT）, aspartate aminotransferase/ alanine aminotransferase （AST/ALT）, serum total bUirubin （TBIL）, prothrombin time （PT）, blood ammonia （AMMO）, and blood urea nitrogen （BUN） were measured after CCh injection. Hepatic pathological changes were also observed.RESULTS： Compared to the other four groups, the changes of group O3 ＋ YC dogs＇ general conditions （motoricity, mental state, eating, urination and defecation） could be better controlled. In group O3 ＋ YC the survival rates were higher （P 〈 0.05 vs group control）. AST/ALT values were kept within a normal level in group O3 ＋ YC. Hepatic histopathology showed that hepatic injury in group O3 ＋ YC was less serious than those in the other four groups.CONCLUSION： Medical ozone combined with TCM YC could exert a protective effect on acute liver injury induced by CCI4,

Microstructure of Ni–Al powder and Ni–Al composite coatings prepared by twin-wire arc spraying

Ni–Al powder and Ni–Al composite coatings were fabricated by twin-wire arc spraying（TWAS）. The microstructures of Ni-5wt%Al powder and Ni-20wt%Al powder were characterized by scanning electronic microscopy（SEM） and energy dispersive spectroscopy（EDS）. The results showed that the obtained particle size ranged from 5 to 50 μm. The morphology of the Ni–Al powder showed that molten particles were composed of Ni solid solution, NiAl, Ni_3Al, Al_2O_3, and NiO. The Ni–Al phase and a small amount of Al_2O_3 particles changed the composition of the coating. The microstructures of the twin-wire-arc-sprayed Ni–Al composite coatings were characterized by SEM, EDS, X-ray diffraction（XRD）, and transmission electron microscopy（TEM）. The results showed that the main phase of the Ni-5wt%Al coating consisted of Ni solid solution and Ni Al in addition to a small amount of Al_2O_3. The main phase of the Ni-20wt%Al coating mainly consisted of Ni solid solution, Ni Al, and Ni_3Al in addition to a small amount of Al and Al_2O_3, and Ni Al and Ni_3Al intermetallic compounds effectively further improved the final wear property of the coatings. TEM analysis indicated that fine spherical NiAl_3 precipitates and a Ni–Al–O amorphous phase formed in the matrix of the Ni solid solution in the original state.

Efficiency and Advantages of Percutaneous Femoroplasty versus Proximal Femoral Replacement for Proximal Femur Metastases

Background: The proximal femur is the most common site of bone metastasis, and metastasis at this site can cause chronic, intolerable pain and even result in pathologic fractures, thereby negatively affecting patients’ quality of life. Selecting an appropriate method for resecting metastasis within the proximal femur requires thorough consideration of various factors, including the biological behavior of the primary tumor, the extent of the femur lesion, the current general systemic condition of the patient, and perioperative risks. Objective: To compare the perioperative safety of and early functional recovery following percutaneous femoroplasty (PFP) and proximal femoral replacement (PFR) in treating patients with metastasis of the proximal femur. Methods: We retrospectively analyzed the cases of 53 patients with proximal femur metastases who received surgical treatment by either PFP (n = 28) or PFR (n = 25). Perioperative blood loss, surgical time, and perioperative complications were compared between groups. Pain intensity according to the visual analogue scale (VAS) and early postoperative function according to the Karnofsky Performance Scale (KPS) were evaluated at 3, 7, and 30 days as well as 6 months after surgical treatment. Results: In the PFP group, the VAS scores were lower soon after operation than preoperation (P 0.05). PFP significantly and immediately improved patients’ quality of life as measured by the KPS in the early period after surgery (preoperative vs 3 days postoperative, P < 0.01), but the patients who underwent PFR suffered a short-term decrease in quality of life (preoperative vs 3 days postoperative, P < 0.01). Blood loss (P < 0.01) and operating time (P < 0.01) were significantly less than PFP. The complication rate was higher in the PFR group (28%) than in the PFP group (3.6%). The results also showed no difference in survival time between the two groups. Conclusion: PFP is an attractive minimally invasive therapeutic option for proximal femur metastasis that can significantly improve the patient’s quality of life in the short term.

Solid electrolyte interphase on anodes in rechargeable lithium batteries

Highly safe and efficient rechargeable lithium batteries have become an indispensable component of the intelligent society powering smart electronics and electric vehicles.This review summarizes the formation principle,chemical compositions,and theoretical models of the solid electrolyte interphase(SEI)on the anode in the lithium battery,involving the functions and influences of the electroactive materials.The discrepancies of the SEI on different kinds of anode materials,as well as the choice and design of the electrolytes are detailedly clarified.Furthermore,the design strategies to obtain a stable and efficient SEI are outlined and discussed.Last but not least,the challenges and perspectives of artificial SEI technology are briefly proposed for the development of high-efficiency batteries in practice.

Establishment and evaluation of an improved rat model of open abdomen

Introduction:This study aimed to establish an animal model of open abdomen(OA)through temporary abdominal closure via different techniques.Methods:Adult male Sprague-Dawley rats were randomly divided into three groups:group A(OA with polypropylene mesh alone);group B(OA with polypro-pylene mesh combined with a patch);and group C(OA with polypropylene mesh and a sutured patch).Vital signs,pathophysiological changes,and survival rates were closely monitored in the rats for 7 days after surgery.Abdominal X-rays and histopathological examinations were performed to assess abdominal organ changes and wound healing.Results:The results showed no significant difference in mortality rates among the three groups(p>0.05).However,rats in group B exhibited superior overall condi-tion,cleaner wounds,and a higher rate of wound healing compared to the other groups(p<0.05).Abdominal X-rays indicated that varying degrees of distal intestinal obstruction in all groups.Histopathological examinations revealed fibrous hyperpla-sia,inflammatory cell infiltration,neovascularization,and collagen deposition in all groups.Group B demonstrated enhanced granulation tissue generation,neovasculari-zation,and collagen deposition compared to the other groups(p<0.05).Conclusions:Polypropylene mesh combined with patches is the most suitable method for establishing an animal model of OA.This model successfully replicated the patho-logical and physiological changes in postoperative patients with OA,specifically the progress of abdominal skin wound healing.It provides a practical and reliable animal model for OA research.

Verticillium dahliae Secretory Effector PevD1 Induces Leaf Senescence by Promoting ORE1-Mediated Ethylene Biosynthesis

Leaf senescence,the final stage of leaf development,is influenced by numerous internal and environmental signals.So far,how biotic stresses such as pathogen infection regulate leaf senescence is unclear.Here,we found that the premature leaf senescence caused by a soil-borne vascular fungus Verticillium dahliae in Arabidopsis was impaired by the mutation of a protein elicitor from V.dahliae 1(PevD1).Constitutive or inducible overexpression of PevD1 accelerated Arabidopsis leaf senescence.A senescence-associated NAC transcription factor,ORE1,was targeted by PevD1.PevD1 interacted with and stabilized ORE1 protein by disrupting its interaction with the RING-type ubiquitin E3 ligase NLA.Mutation of ORE1 suppressed the premature senescence caused by overexpressing PevD1.Overexpression of ORE1 or PevD1 led to enhanced ethylene production,and ORE1 mediated PevD1-induced ethylene biosynthesis by directly binding to the ACS6 promoter.Loss-of-function of ACSs suppressed V.dahliae-induced leaf senescence in ORE1-overexpressing plants.Interestingly,PevD1 also interacted with Gossypium hirsutum ORE1(GhORE1),and virus-induced gene silencing of GhORE1 delayed V.dahliae-triggered leaf senescence in cotton,indicative of the existence of a conserved mechanism in plants.Altogether,our study demonstrates that V.dahliae induces leaf senescence by secreting the effector PevD1 to regulate the ORE1-ACS6 cascade,providing new insight into biotic stress-induced senescence in plants.

Structural Basis of RACK7 PHD Domain to Read a Pediatric Glioblastoma-Associated Histone Mutation H3.3G34R

Histone point mutations,including missense mutations on histone H3 at positions 27(K27M),34(G34R/V,G34W,G34L)and 36(K36M),were identified as potential cancer driver mutations.H3.3G34R/V mutations account for pediatric glioblastomas(GBM).RACK7(also known as ZMYND8,PRKCBP1)was recently reported to specifically bind H3.3G34R through its PHD(plant homedomain)domain(PHDRACK7)in vitro and in H3.3G34R pediatric glioblastoma cells,playing key roles in H3.3G34R-mediated gene transcription.Herein,we provided both biochemical and NMR structural evidences that PHDRACK7 recognized histone H3.3G34R mutant via a mechanism distinet from all other reported PHD domains.Except the reported residue D104,two new sites D108 and L121 of PHD^(RACK7) were found necessary for the interactions between PHD^(RACK7) and histone H3.3G34R peptide.Our results provided a potential molecular basis for pediatric GBM driven by the H3.3G34R mutation.