Delay-CJ:A novel cryptojacking covert attack method based on delayed strategy and its detection

Cryptojacking is a type of resource embezzlement attack,wherein an attacker secretly executes the cryptocurrency mining program in the target host to gain profits.It has been common since 2017,and in fact,it once became the greatest threat to network security.To better prove the attack ability the harm caused by cryptojacking,this paper proposes a new covert browser-based mining attack model named Delay-CJ,this model was deployed in a simulation environment for evaluation.Based on the general framework of cryptojacking,Delay-CJ adds hybrid evasion detection techniques and applies the delayed execution strategy specifically for video websites in the prototype implementation.The results show that the existing detection methods used for testing may become invalid as result of this model.In view of this situation,to achieve a more general and robust detection scheme,we built a cryptojacking detection system named CJDetector,which is based on cryptojacking process features.Specifically,it identifies malicious mining by monitoring CPU usage and analyzing the function call information.This system not only effectively detects the attack in our example but also has universal applicability.The recognition accuracy of CJDetector reaches 99.33%.Finally,we tested the web pages in Alexa 50K websites to investigate cryptojacking activity in the real network.We found that although cryptojacking is indeed on the decline,it remains a part of network security threats that cannot be ignored.

Valence state effect of Cu on photocatalytic CO_(2)reduction

Copper(Cu)is extensively employed in photocatalytic CO_(2)reduction reactions for the production of high-value products.The valence state of transition metals plays a pivotal role in influencing the catalytic process.However,due to the complex valence state changes of Cu in the CO_(2)reduction reaction,research on its valence state effect is lacking.The current work is to prepare a series of TiO_(2)/CuX with stable Cu valence composition using different copper halides(CuX and CuX_(2),X=Br or Cl)as precursors.The results show that the CuBr_(2)loading leads to Cu^(+)/Cu^(2+) mixed cocatalyst and exhibits the highest activity for CO_(2)photoreduction.The CH4 evolution rate of the TiO_(2)/CuBr_(2)catalyst is as high as 100.59μmol h^(-1)g^(-1),which is 6.6 times that of pristine TiO_(2).The CH4 selectivity reaches 77%.The enhanced catalytic activity and selectivity can be ascribed to the efficient surface adsorption,activation,excellent carrier separation,and transfer ofCu^(+)/Cu^(2+) mixed cocatalyst.Our findings provide a reference for designing highly active Cu-based photocatalysts.

Improved Isolation Forest Algorithm for Anomaly Test Data Detection

The cigarette detection data contains a large amount of true sample data and a small amount of false sample data. The false sample data is regarded as abnormal data, and anomaly detection is performed to realize the identification of real and fake cigarettes. Binary particle swarm optimization algorithm is used to improve the isolation forest construction process, and isolation trees with high precision and large differences are selected, which improves the accuracy and efficiency of the algorithm. The distance between the obtained anomaly score and the clustering center of the k-means algorithm is used as the threshold for anomaly judgment. The experimental results show that the accuracy of the BPSO-iForest algorithm is improved compared with the standard iForest algorithm. The experimental results of multiple brand samples also show that the method in this paper can accurately use the detection data for authenticity identification.

Effect of temperature difference load of 32 m simply supported box beam bridge on track vertical irregularity

In order to study the effect of temperature difference load （TDL） along the vertical direction of a simply supported beam bridge section on the vertical irregularity, a rail-bridge-piers calculation model was established. Taking 32 m simply supported box beam bridge which is widely used in the construction of pas- senger dedicated line in China as an example, influences of the temperature variation between the bottom and top of the bridge, temperature curve index, type of temperature gradient, and beam height on track vertical irregularity were analyzed with the model. The results show that TDL has more effects on long wave track irregularity than on short one, and the wavelength mainly affected is approxi- mately equal to the beam span. The amplitude of irregu- larity caused by TDL is largely affected by the temperature variation, temperature curve index, and type of temperature gradient, so it is necessary to monitor the temperaturedistribution of bridges in different regions to provide accurate calculation parameters. In order to avoid the irregularity exceeding the limit values, the height of 32, 48, and 64 m simply supported box beam bridges must not be less than 2.15, 3.2, and 4.05 m, respectively.

Seroprevalence of Toxoplasma gondii infection in dogs and cats in Zhenjiang City,Eastern China

Objective:To determine the seroprevalence of Toxoplasma gondii(T.gondii) infection in dogs and cats in Zhenjiang City,Jiangsu Province.Eastern China,and to evaluate the main associated risk factors relating to exposure to 71 gondii in this region.Methods:Sera from 160 clogs and 116 cats from Zhenjiang City were tested for anti-T.gondii antibodies using EUSA.The seropositivity by area of activity,sex and age was analyzed.Results:Overall.21 dogs(13.l%) and 24 cats(20.7%) had antibodies to T.gondii.The infection rate in stray dogs(38.7%) and cats(28.6%! was significantly higher(P<0.05) than in household dogs(6.9%) and cats(18.2%).The seroprevalence in male clogs(14.8%) and cats(21.05%) were slighlly higher than their female counterparts(11.4%in dogs and 20.0%in cats),but were not significantly differenent(P>0.05).A high proportion of dogs at 3 to 6 years of age were positive to T.gondii(20.0%)while cats with relatively high seropositivity rates were at 0 to 1 year of age(33.3%).Conclusions:The prevalence of T.gondii infection in dogs and cats in Zhenjiang City was high,which is probably the main source of T.gondii infection in this area.

Influence of overweight in pregnancy on the intestinal flora as well as maternal and infant outcome

Currently,the influence of change in the intestinal flora on the human body has become a popular topic for clinical research.Several studies show that the nutritional balance,physiological metabolism,immune protection,and even the occurrence and development of various chronic diseases are related to the change in intestinal flora.This chapter focuses on the changes in the intestinal microflora in pregnant women and the impact on the health of their offspring in order to provide some theoretical basis for clinical guidance.

Bifunctional core–shell co-catalyst for boosting photocatalytic CO_(2) reduction to CH_(4)

Solar-light-driven CO_(2) reduction CO to CH_(4) and C2H6 is a complex process involving multiple elementary reactions and energy barriers.Therefore,achieving high CH_(4) activity and selectivity remains a significant challenge.Here,we integrate bifunctional Cu2O and Cu-MOF(MOF=metal-organic framework)core–shell co-catalysts(Cu2O@Cu-MOF)with semiconductor TiO_(2).Experiments and theoretical calculations demonstrate that Cu2O(Cu+facilitates charge separation)and Cu-MOF(Cu2+improves the CO_(2) adsorption and activation)in the core–shell structure have a synergistic effect on photocatalytic CO_(2) reduction,reducing the formation barrier of the key intermediate*COOH and*CHO.The photocatalyst exhibits high CH_(4) yield(366.0μmol·g^(-1)·h^(-1)),efficient electron transfer(3283μmol·g^(-1)·h^(-1))and hydrocarbon selectivity(95.5%),which represents the highest activity of Cu-MOF-based catalysts in photocatalytic CO_(2) reduction reaction.This work provides a strategy for designing efficient photocatalysts from the perspective of precise regulation of components.

Solution-processed all-inorganic lead halide perovskite/layered double hydroxides superlattices

Quantum wells and superlattices are key building blocks in the semiconductor industry,normally fabricated using epitaxial growth techniques,such as vapor phase epitaxy,metalorganic chemical vapor deposition and molecular beam epitaxy.However,these complicated preparation processes,as well as their high cost,limit their extensive applications.It is essential to develop a simple solution process for building superstructures.Here,we demonstrate an ion exchange strategy for synthesizing an allinorganic superlattice cesium lead bromide/layered double hydroxides(CsPbBr_3/LDH)in solution.At room temperature,the perovskite ions diffuse into the interlayer of LDH and assemble into layered perovskite with various thicknesses.Compared with traditional organic-inorganic hybrid perovskite superlattice,the all-inorganic perovskite superlattice CsPbBr_(3)/LDH has weak quantum confinement,which exhibits narrow emission line-widths of 20 nm,high quantum yields of 55%,and radiative lifetimes of several ns.Our findings offer a new route to synthesize novel perovskite superlattices and enrich the perovskite supercrystal platform for electronics,photonics and optoelectronics devices.

Mechanism of Metabolic Dysfunction-associated Steatotic Liver Disease:Important role of lipid metabolism

Metabolic dysfunction-associated steatotic liver disease(MASLD),formerly known as non-alcoholic fatty liver disease,has a high global prevalence and can progress to metabolic dysfunction-associated steatohepatitis,cirrhosis,and hepatocellular carcinoma.The pathogenesis of MASLD is primarily driven by disturbances in hepatic lipid metabolism,involving six key processes:increased hepatic fatty acid uptake,enhanced fatty acid synthesis,reduced oxidative degradation of fatty acids,increased cholesterol uptake,elevated cholesterol synthesis,and increased bile acid synthesis.Consequently,maintaining hepatic lipid metabolic homeostasis is essential for effective MASLD management.Numerous novel molecules and Chinese proprietary medicines have demonstrated promising therapeutic potential in treating MASLD,primarily by inhibiting lipid synthesis and promoting lipid oxidation.In this review,we summarized recent research on MASLD,elucidated the molecular mechanisms by which lipid metabolism disorders contribute to MASLD pathogenesis,and discussed various lipid metabolism-targeted therapeutic approaches for MASLD.

Pt-surface oxygen vacancies coupling accelerated photo-charge extraction and activated hydrogen evolution

Semiconductors-based heterogeneous photocatalytic water splitting has been extensively studied,but it still remains challenging to accelerate the separation of electron-hole pairs and facilitate the reaction kinetics.Here we report a general strategy to fabricate highly efficient Pt/TiO_(2)photocatalyst by coupling the Pt co-catalysts and surface oxygen vacancies(VO)of TiO_(2).TiO_(2)was pre-modified with alkali or alkaline earth metals ion solutions,which produce a large number of surface hydroxyl on TiO_(2).Subsequently,the photodeposited Pt sub-nanoparticles substitute surface hydroxyl and induce surface VO on TiO_(2).The coupling of Pt and surface VO on TiO_(2)can accelerate the extraction of photo-charges through the interaction of Pt-VO-Ti bonds and reduce the hydrogen evolution barrier,thereby promoting the photocatalytic activity.The synthesized Pt-VO-TiO_(2)sample exhibits a photocatalytic hydrogen evolution activity as high as 1.5 L·g^(−1)·h^(−1),which is 2.2 times that of traditional Pt/TiO_(2).Our findings indepth understand the synergistic effect of co-catalysts and defects on photocatalysis and open up new possibilities for achieving robust photocatalytic water splitting.

Predictably synthesizing a library of white-light-emitting perovskites

The low-dimensional organic-inorganic halide perovskites with self-trapped exciton emission have promising prospects for single-phase white-light emitters. However, so far, these broadband white-light-emitting(BWLE) perovskites were synthesized by trial-and-error testing spacing molecules. Here, we developed a steric hindrance regulation strategy to predictably synthesize BWLE perovskites. The molecules containing C–C(–NH_(2))–C groups were introduced into low-dimensional perovskites, which brings a large steric hindrance in-plane orientation. The bigger C–C(–NH_(2))–C bond angle would induce larger structural distortion in perovskites, which leads to the higher rate of self-trapping of excitons and the deeper self-trapping depth. The photoluminescence spectra of the synthesized perovskites can cover the cool-to-warm white light region. Overall, we fabricated a material library consisting of 40 kinds of BWLE compounds according to this strategy. Our findings develop a general strategy to synthesize BWLE perovskites and offer a material platform for optoelectronic applications.

轧制温度对耐候热轧H型钢力学性能的影响

根据热轧H型钢翼缘厚度方向变形集中在万能轧制阶段的特点,将万能阶段开轧温度设定在800~1000℃,其余主要工艺参数不变。通过对热轧H型钢进行力学性能检验及显微组织对比分析,发现铁素体晶粒尺寸及外形对产品力学性能有至关重要的影响,而万能阶段开轧温度对铁素体晶粒尺寸及外形存在显著影响。当开轧温度在1000~950℃时,虽然能够实现奥氏体动态再结晶,但在轧后分别从900和850℃空冷时,再结晶晶粒长大迅速,也易出现反常长大。当开轧温度为1000℃时,铁素晶粒尺寸不一,存在明显的混晶,当温度降低至950℃时,虽然混晶情况有所改善,但依然无法消除。在温度降低至900℃时,不仅能够完成奥氏体动态再结晶,而且轧后空冷起始温度降低至800℃,再结晶晶粒长大被抑制,形成了细小且均匀的初始奥氏体组织,此时的铁素体晶粒为10~30μm的等轴状。当温度进一步降低至850~800℃时,因无法达到促进奥氏体动态再结晶的热激活能需求,仅在未再结晶区进行了变形,最终形成扁平状铁素体晶粒,长轴与短轴尺寸比例接近2∶1,长轴尺寸减小不明显,短轴尺寸进一步减小。正因为如此,随着开轧温度从1000℃降低至900℃,铁素体晶粒尺寸减小,从而增加了晶界面积,降低了应力集中程度,增大了瞬时变形的均匀分配能力,使得产品屈服强度从369 MPa升高至415 MPa,抗拉强度从508 MPa升高至546 MPa,断后伸长率从30.0%升高至31.5%,低温冲击功均值从36 J提升至99 J;当温度降低至850~800℃时,扁平状铁素体晶粒进一步增大了晶界面积,使得产品屈服强度和抗拉强度分布进一步升高至468 MPa和567 MPa,但由于长、短轴差距增大,导致塑性变形时需要协调转动而产生畸变能,断后伸长率降低至27.5%,低温冲击功均值提升至109 J,此时屈强比已达到0.83。鉴于降低开轧温度影响生产节奏,同时考虑万能轧机负荷、能耗及辊耗等经济因素,900~850℃是较为理想的开轧温度区间,此时产品不仅强度及塑性指标均保持在较高的水平,而且韧性指标大幅提升,耐候热轧H型钢的综合力学性能得到明显改善。

Efficient up-conversion photoluminescence in all-inorganic lead halide perovskite nanocrystals

Up-conversion photoluminescence(UCPL)refers to the elementary process where low-energy photons are converted into high-energy ones via consecutive interactions inside a medium.When additional energy is provided by intermnal thermal energy in the form of lttice vibrations(phonons),the process is called phonon-assisted UCPL.Here,we report the exceptionally large phonon-assisted energy gain of up to^8kgT(kg is Boltzmann constant,T is temperature)on all-inorganic lead halide perovskite semiconductor colloidal nanocrystals that goes beyond the maximum capabilty of only harvesting optical phonon modes.By systematic optical study in combination with a statistical probability model,we explained the nontrivial phonon-assisted UCPL process in perovskites nanocrystals,where in addition to the strong electron-phonon(light-matter)coupling,other nonlinear processes such as phonon-phonon(matter-matter)interaction also effectively boost the up-conversion efficiency.

Modulating the optical and electrical properties of MAPbBr_(3) single crystals via voltage regulation engineering and application in memristors

Defect density is one of the most significant characteristics of perovskite single crystals(PSCs)that determines their optical and electrical properties,but few strategies are available to tune this property.Here,we demonstrate that voltage regulation is an efficient method to tune defect density,as well as the optical and electrical properties of PSCs.A three-step carrier transport model of MAPbBr_(3) PSCs is proposed to explore the defect regulation mechanism and carrier transport dynamics via an applied bias.Dynamic and steady-state photoluminescence measurements subsequently show that the surface defect density,average carrier lifetime,and photoluminescence intensity can be efficiently tuned by the applied bias.In particular,when the regulation voltage is 20 V(electrical poling intensity is 0.167 Vμm^(−1)),the surface defect density of MAPbBr_(3) PSCs is reduced by 24.27%,the carrier lifetime is prolonged by 32.04%,and the PL intensity is increased by 112.96%.Furthermore,a voltage-regulated MAPbBr_(3) PSC memristor device shows an adjustable multiresistance,weak ion migration effect and greatly enhanced device stability.Voltage regulation is a promising engineering technique for developing advanced perovskite optoelectronic devices.

SERS study on the synergistic effects of electric field enhancement and charge transfer in an Ag2S quantum dots/plasmonic bowtie nanoantenna composite system

Localized surface plasmon resonance(LSPR)of nanostructures and the interfacial charge transfer(CT)of semiconductor materials play essential roles in the study of optical and photoelectronic properties.In this paper,a composite substrate of Ag2S quantum dots(QDs)coated plasmonic Au bowtie nanoantenna(BNA)arrays with a metalinsulator-metal(MIM)configuration was built to study the synergistic effect of LSPR and interfacial CT using surface-enhanced Raman scattering(SERS)in the near-infrared(NIR)region.The Au BNA array structure with a large enhancement of the localized electric field(E-field)strongly enhanced the Raman signal of adsorbed p-aminothiophenol(PATP)probe molecules.Meanwhile,the broad enhanced spectral region was achieved owing to the coupling of LSPR The as-prepared Au BNA array structure facilitated enhancements of the excitation as well as the emission of Raman signal simultaneously,which was established by finite-difference time-domain simulation.Moreover,Ag2S semiconductor QDs were introduced into the BNA/PATP system to further enhance Raman signals,which benefited from the interfacial CT resonance in the BNA/Ag2S-QDs/PATP system.As a result,the Raman signals of PATP in the BNA/Ag2S-QDs/PATP system were strongly enhanced under 785 nm laser excitation due to the synergistic effect of E-field enhancement and interfacial CT.Furthermore,the SERS polarization dependence effeas of the BNA/Ag2S-QDs/PATP system were also investigated.The SERS spectra indicated that the polarization dependence of the substrate increased with decreasing polarization angles(θpola)of excitation from p-polarized(θpola=90°)excitation to s-polarized(θpola=0°)excitation.This study provides a strategy using the synergistic effect of interfacial CT and E-field enhancement for SERS applications and provides a guidance for the development of SERS study on semiconductor QD-based plasmonic substrates,and can be farther extended to other material-nanostructure systems for various optoelectronic and sensing applications.

Wireless electrical stimulation at the nanoscale interface induces tumor vascular normalization

Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.

Deposition of SnO2 on the Anatase TiO2 {105} Facets with High Photocatalytic Performance

Anatase TiO2 as a promising photocatalyst has been widely employed in the decontamination treatment of polluted water, air purification and water splitting. Coupling TiO2 with other semiconductor materials could further enhance the photocatalytic activity. Here, we successfully synthesized the SnOz/TiO2 catalyst by depositing SnO2 particles on the anatase TiO2 {105} facets through a gas phase oxidation process. The SnOz/TiO2 catalyst shows higher photocatalytic activity for decomposition of MB than that of the pure YiO2 catalyst. The enhanced photo- catalytic activity can be attributed to the efficient charge separation since TiO2 and SnO2 catalyst have staggered energy level.

Potential development of all-inorganic perovskites

The energy consump tion is increasing rapidly with the continuous development of human society.Currently,global energy still mainly depends on fossil fuels.As awareness of the negative impact on the environment of burning fossil fuels,much attention has put on exploring clean and renewable energy.The solar energy has got the limitless foreground as a kind of renewable energy and photovoltaic devices can convert solar energy into electricity directly.