Robust blind image watermarking based on interest points

Digital watermarking technology plays an essential role in the work of anti-counterfeiting and traceability.However,image watermarking algorithms are weak against hybrid attacks,especially geometric attacks,such as cropping attacks,rotation attacks,etc.We propose a robust blind image watermarking algorithm that combines stable interest points and deep learning networks to improve the robustness of the watermarking algorithm further.First,to extract more sparse and stable interest points,we use the Superpoint algorithm for generation and design two steps to perform the screening procedure.We first keep the points with the highest possibility in a given region to ensure the sparsity of the points and then filter the robust interest points by hybrid attacks to ensure high stability.The message is embedded in sub-blocks centered on stable interest points using a deep learning-based framework.Different kinds of attacks and simulated noise are added to the adversarial training to guarantee the robustness of embedded blocks.We use the ConvNext network for watermark extraction and determine the division threshold based on the decoded values of the unembedded sub-blocks.Through extensive experimental results,we demonstrate that our proposed algorithm can improve the accuracy of the network in extracting information while ensuring high invisibility between the embedded image and the original cover image.Comparison with previous SOTA work reveals that our algorithm can achieve better visual and numerical results on hybrid and geometric attacks.

高能喷丸制备具有表面梯度结构的Ti-6Al-4V合金的疲劳裂纹扩展行为

通过高能喷丸(HESP)在Ti-6Al-4V合金表面成功制备梯度结构,并研究其对疲劳裂纹扩展的影响。采用光学显微镜、扫描电子显微镜、透射电子显微镜和X射线衍射仪对HESP过程中的显微组织和残余应力演变进行表征。结果表明,材料表面形成的梯度纳米结构具有220μm深度的残余压应力层。梯度纳米结构的产生能改善合金的强塑性匹配。最大残余压应力产生于次表层,且随着喷丸时间的增加逐渐增大。HESP处理有效降低裂纹扩展速率,提高疲劳裂纹扩展寿命。残余压应力可降低裂纹尖端的有效应力强度因子范围(ΔK’eff),从而产生裂纹闭合效应并延缓裂纹扩展。同时,晶粒细化引起的晶界增加、有效滑移长度减小和裂纹尖端塑性区的协同作用也会使裂纹扩展阻力增大。

Design and development of multi-channel front end electronics based on dual-polarity charge-to-digital converter for SiPM detector applications

With the development of silicon photomultiplier(SiPM)technology,front-end electronics for SiPM signal processing have been highly sought after in various fields.A compact 64-channel front-end electronics(FEE)system achieved by fieldprogrammable gate array-based charge-to-digital converter(FPGA-QDC)technology was built and developed.The FEE consists of an analog board and FPGA board.The analog board incorporates commercial amplifiers,resistors,and capacitors.The FPGA board is composed of a low-cost FPGA.The electronics performance of the FEE was evaluated in terms of noise,linearity,and uniformity.A positron emission tomography(PET)detector with three different readout configurations was designed to validate the readout capability of the FEE for SiPM-based detectors.The PET detector was made of a 15×15 lutetium–yttrium oxyorthosilicate(LYSO)crystal array directly coupled with a SiPM array detector.The experimental results show that FEE can process dual-polarity charge signals from the SiPM detectors.In addition,it shows a good energy resolution for 511-keV gamma photons under the dual-end readout for the LYSO crystal array irradiated by a Na-22 source.Overall,the FEE based on FPGA-QDC shows promise for application in SiPM-based radiation detectors.

Zr−Co−Ge三元体系在1023、1173和1373 K条件下的相平衡

采用合金法并结合电子探针显微分析(EPMA)和X射线衍射(XRD)技术,精确测定Zr−Co−Ge三元体系在1023、1173和1373 K条件下的相平衡。合理构建Zr−Co−Ge体系在1023、1173和1373 K条件下的等温截面,分别包含29、28和26个三相区。除了证实文献中报道的5个三元化合物外,还检测到一个具有显著均匀性范围的新三元相τ,其组成在1023 K时为13.8%~19.4%Co(摩尔分数),在1173 K时为12.9%~19.0%Co(摩尔分数)和在1373 K时为12.3%~14.9%Co(摩尔分数)。而且,推断一个零变量反应发生在1023~1173 K,即τ+τ1τ4+ZrGe2。此外,第三种元素Ge在一些Co−Zr中间相中可以部分替代Co,如CoZr2和Co23Zr6,其中,Ge的最大溶解度分别可达22.8%和20.3%(摩尔分数)。

Oxidation of ciprofloxacin by the synergistic effect of DBD plasma and persulfate:reactive species and influencing factors analysis

A synergistic system of water falling film dielectric barrier discharge(DBD)plasma and persulfate(PS)was set up and used for oxidizing ciprofloxacin(CIP)in water.Results of reactive species formation in the DBD-only system as well as the DBD–PS system verified the PS activation in the DBD system.Influencing factors on CIP degradation and the degradation process were also been studied.The obtained results showed that the presence of PS could greatly improve the degradation and mineralization of CIP and that the degradation efficiency could reach 97.73%after only 40 min treatment with 4 m M PS addition.The increase of PS concentration,the lower CIP concentration,the acidic solution p H and the addition of metal ions(Fe^(2+)and Cu^(2+))enhanced the CIP degradation,while the existence of Cl^(-)and HCO_(3)^(-)had a negative effect.The experiments related to scavenger addition confirmed the contribution of the main reactive species to the CIP oxidation.Three probable degradation pathways were proposed by analyzing the inorganic ions and organic byproducts formed during the CIP degradation.The toxicity evaluation results of the CIP and its intermediates confirmed the effectiveness of the DBD–PS synergistic system.

Heart rate response and recovery during exercise predict future delirium risk——A prospective cohort study in middle-to older-aged adults

Background:Delirium is a neurocognitive disorder characterized by an abrupt decline in attention,awareness,and cognition after surgical/illness-induced stressors on the brain.There is now an increasing focus on how cardiovascular health interacts with neurocognitive disorders given their overlapping risk factors and links to subsequent dementia and mortality.One common indicator for cardiovascular health is the heart rate response/recovery(HRR)to exercise,but how this relates to future delirium is unknown.Methods:Electrocardiogram data were examined in 38,740 middle-to older-aged UK Biobank participants(mean age=58.1 years,range:40-72 years;47.3%males)who completed a standardized submaximal exercise stress test(15-s baseline,6-min exercise,and 1-min recovery)and required hospitalization during follow-up.An HRR index was derived as the product of the heart rate(HR)responses during exercise(peak/resting HRs)and recovery(peak/recovery HRs)and categorized into low/average/high groups as the bottom quartile/middle 2 quartiles/top quartile,respectively.Associations between 3 HRR groups and new-onset delirium were investigated using Cox proportional hazards models and a2-year landmark analysis to minimize reverse causation.Sociodemographic factors,lifestyle factors/physical activity,cardiovascular risk,comorbidities,cognition,and maximal workload achieved were included as covariates.Results:During a median follow-up period of 11 years,348 participants(9/1000)newly developed delirium.Compared with the high HRR group(16/1000),the risk for delirium was almost doubled in those with low HRR(hazard ratio=1.90,95%)confidence interval(95%CI):1.30-2.79,p=0.001)and average HRR(hazard ratio=1.54,95%CI:1.07-2.22,p=0.020)).Low HRR was equivalent to being 6 years older,a current smoker,or>3 additional cardiovascular disease risks.Results were robust in sensitivity analysis,but the risk appeared larger in those with better cognition and when only postoperative delirium was considered(n=147;hazard ratio=2.66,95%CI:1.46-4.85,p=0.001).Conclusion:HRR during submaximal exercise is associated with future risk for delirium.Given that HRR is potentially modifiable,it may prove useful for neurological risk stratification alongside traditional cardiovascular risk factors.

Posterior scleral application of a mitomycin C-soaked sponge during trabeculectomy

AIM:To evaluate the safety and efficacy of posterior scleral application(a modified technique)of an antimetabolite mitomycin C-soaked sponge in trabeculectomy for patients with glaucoma.METHODS:This retrospective study included 101 patients(115 eyes)with glaucoma(aged 12–83y)who underwent trabeculectomy using a modified mitomycin C-soaked sponge placement method.A piece of 3.5×10 mm2 sponge was placed vertically and posteriorly with the long side perpendicular to the limbus.The mitomycin C concentration and exposure time were 0.2–0.5 mg/m L and 1–5min,respectively.Intraocular pressure,bestcorrected visual acuity,and hypotensive medications were recorded at baseline and at the final visit.Complications,interventions required,and bleb morphology were recorded postoperatively.The primary outcome was trabeculectomy safety,including complications and bleb morphology;the secondary outcome was the trabeculectomy success rate.RESULTS:At the final follow-up[median 28mo,range 7–67mo and interquartile range(IQR)13mo],the qualified(cumulative)success rate was 93.0%and the complete success rate was 60.0%.No bleb-related complications were observed.The mean height,extent,and vascularity grades were 0.6±0.9,1.1±0.4,and 2.4±0.9,respectively.All Seidel tests were negative.The mean posteriority grade was 0.8±0.4.CONCLUSION:Trabeculectomy with the long side of a mitomycin C-soaked sponge placed perpendicular to the corneal limbus is safe and effective.

Four new lanostane triterpenoids featuring extendedπ-conjugated systems from the stems of Kadsura coccinea

Four new 14(13→12)-abeolanostane triterpenoids featuring extendedπ-conjugated systems,kadcoccitanes E-H(1-4),were obtained from the stems of Kadsura coccinea through using a HPLC−UV-guided approach.Their structural and configurational determination was accomplished through extensive spectroscopic analysis coupled with quantum chemical calculations.Kadcoccitanes E-H were tested for their cytotoxic activities against five human tumor cell lines(HL-60,A-549,SMMC-7721,MDA-MB-231,SW-480)but none of them exhibited activities at the concentration 40μM.

Numerical and experimental studies on solidification of AZ80 magnesium alloy under out-of-phase pulsed magnetic field

For obtaining the finer grains of magnesium alloy,a novel combined pulsed magnetic field with different initial phases,also called out-ofphase pulsed magnetic field(OPPMF),was applied to study the solidification structure of AZ80 magnesium alloy.The numerical simulation was simultaneously conducted to investigate the refinement mechanisms.The experimental results showed that the macrostructure could be effectively refined by applying external magnetic field.Meanwhile,finer grains were obtained with the higher current intensity.However,the increase of current intensity could only refine the grains to about 0.5 mm.Furthermore,compared to a single pulsed magnetic field(PMF)and alternating series of OPPMF(Connection II),a finer structure was observed when the consecutive series of OPPMF(Connection I)was imposed.In contrast with a single PMF and Connection II,the numerical results showed that the greater axial Lorentz force was obtained under the Connection I,generating the stronger forced flow in the melt.It is believed that abundant nuclei could detach from the mold wall and move faster into the interior melt due to the stronger forced flow;besides,the lower superheat and greater temperature uniformity in bulk melt were realized,accounting for the finest structures under the Connection I.

Effects of nano-SiC_p content on microstructure and mechanical properties of SiC_p/A356 composites assisted with ultrasonic treatment

nano-SiCp/A356 composites with different nano-SiCp contents were prepared by squeeze casting after ultrasonic treatment（UT）. The effects of SiCp content on the microstructure and mechanical properties of the nanocomposites were investigated. Theresults show that with the addition of nano-SiCp, the microstructure of nanocomposites is obviously refined, the morphology of theα（Al） grains transforms from coarse dendrites to rosette crystals, and long acicular eutectic Si phases are shortened and rounded. Themechanical properties of 0.5%, 1% and 2% （mass fraction） SiCp/A356 nanocomposites are improved continuously with the increaseof nano-SiCp content. Especially, when the SiCp content is 2%, the tensile strength, yield strength and elongation are 259 MPa,144 MPa and 5.3%, which are increased by 19%, 69% and 15%, respectively, compared with those of the matrix alloy. Theimprovement of strength is attributed to mechanisms of Hall？Petch strengthening and Orowan strengthening.

Crystal Structures, Stability, and Solubility Evaluation of a 2:1 Diosgenin-Piperazine Cocrystal

A cocrystal of diosgenin with piperazine in 2:1 stoichiometry was successfully synthesized.The solid form was prepared by liquid assisted grinding,slurry and crystallization methods.The cocrystal was characterized by powder X-ray diffraction,differential scanning calorimetry,thermogravimetric analysis,Fourier transform infrared spectroscopy,and structure determined by single crystal X-ray diffraction,the hydrogen bonds formed into fish bone structure along the[010]direction and all the molecules packed into 3D layer structure along a axis.After formation of cocrystal,the solubility of diosgenin was improved,and the solubility value in 0.2%SDS solution was approximately 1.5 times as large as that of the parent material.

Four 14(13→12)‑Abeolanostane Triterpenoids with 6/6/5/6‑Fused Ring System from the Roots of Kadsura coccinea

Four new rearranged 6/6/5/6-fused lanostane-type triterpenoids,kadcoccitanes A-D(1-4),were isolated from the roots of Kadsura coccinea,and their structures were mainly elucidated by comprehensive analysis of their spectroscopic data.Additionally,the structure of 1 was ambiguously verifed by single-crystal X-ray difraction,while the structure of 2,which features a novel 8,16-epoxy motif,was validated by quantum chemical calculation of NMR parameters and ECD spectrum.Moreover,1 and 4 were found to exhibited anticoagulant activity,while 3 and 4 were found to possess anti-platelet aggregation activity.

Nano-SiC_P particles distribution and mechanical properties of Al-matrix composites prepared by stir casting and ultrasonic treatment

Nano-ceramic particles are generally difficult to add into molten metal because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new complex process, i.e., a molten-metal process combined with high energy ball milling and ultrasonic vibration methods. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850 ℃ to form an oxide layer with a thickness of approximately 3 nm. The mm-sized composite granules containing nano-SiCp were firstly produced by milling the mixture of oxidized nano-SiCp and pure Al powders, and then were remelted in the matrix-metal melt with mechanical stirring and treated by ultrasonic vibration to prepare the composite. SEM analysis results show that the nano-SiC particles are distributed uniformly in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the composite with 2wt.% nano-SiCp in as-cast state are 226 MPa and 5.5％, improved by 20％ and 44％, respectively, compared with the A356 alloy.

Crystal structures and elastic properties of Ti(Cu,Pt)2 and Ti(Cu,Pt)3 phases

This paper focused on the crystal structures of two new ternary phases,Ti(Cu,Pt)2 and Ti(Cu,Pt)3,which were studied by X-ray powder diffraction data using Rietveld method.Electron probe microanalysis was used for sample composition examination.Elastic properties of these phases were further measured by nano-indentation,and meanwhile calculated with first-principle(FP)calculations.It is found that the crystal structure of Ti(Cu,Pt)2 is of orthorhombic cell space group Amm2(No.38)with structural prototype of VAu2.The resolved structure of Ti(Cu,Pt)3 is of tetragonal Al Pt3 type,belonging to the space group P4/mmm(No.123).The nano-indentation measurement and FP calculations show that the elastic modulus of Ti(Cu,Pt)2 increases firstly then decreases with Pt content,whereas that of Ti(Cu,Pt)3almost linearly increases with Pt content.

融合基因与膀胱癌

融合基因在泌尿系统肿瘤特别是膀胱癌中的研究逐年增多,越来越多的融合基因被发现。本文旨在回顾融合基因领域的研究成果,总结融合基因在膀胱癌中的最新研究进展,展望未来融合基因在膀胱癌研究中可能的发展方向。

Chinese Spirits Identification Model Based on Mid-Infrared Spectrum

Applying computer technology to the field of food safety,and how to identify liquor quickly and accurately,is of vital importance and has become a research focus.In this paper,sparse principal component analysis(SPCA)was applied to seek sparse factors of the mid-infrared(MIR)spectra of five famous vintage year Chinese spirits.The results showed while meeting the maximum explained variance,23 sparse principal components(PCs)were selected as features in a support vector machine(SVM)model,which obtained a 97%classification accuracy.By comparison principal component analysis(PCA)selected 10 PCs as features but only achieved an 83%classification accuracy.Although both approaches were better than a direct SVM approach based on the classification results(64%classification accuracy),they also demonstrated the importance of extracting sparse PCs,which captured most important information.The combination of computer technology SPCA and MIR provides a new and convenient method for liquor identification in food safety.

Arthrinins E-G, Three Botryane Sesquiterpenoids from the Plant Endophytic Fungus Arthrinium sp. HS66

Arthrinins E-G(1-3),three new sesquiterpenoids possessing non-isoprenoid botryane skeleton,were isolated from the fermentation of an endophytic fungus named Arthrinium sp.HS66 which colonized in the stems of Isodon xerophilus.Their structures were determined by extensive spectroscopic methods.Furthermore,the structure of 1 was unambiguously confirmed by X-ray diffraction,while those of 2 and 3 were verified through quantum chemical calculation of NMR data and ECD spectra.

Lignans and sesquiterpenoids from the stems of Schisandra bicolor var. tuberculata

A pair of new tetrahydrofuran lignan enantiomers,(±)-schibiculatin A[(±)-1],a new enedione lignan,schibiculatin B(2),two new cadinane-type sesquiterpenoids,schibiculatins C(3)and D(4),along with two known seco-cadinane-type sesquiterpenoids(5 and 6)and seven known miscellaneous lignans(7-13)were isolated from the stems of Schisandra bicolor var.tuberculata.The structures of 1-4 were elucidated by comprehensive analysis of their spectro-scopic data,quantum chemical calculations,as well as single-crystal X-ray diffraction.A few isolated compounds were tested for their protective activities against corticosterone-induced apoptosis in PC12 cells.Among them,compounds 5 and 6 showed moderate activities.

Preliminary investigation and detection based on loop-mediated isothermal amplification(LAMP)of phytoplasmas associated with diseases in B.napus L.

In the last decade,some disease occurred on our experimental farms that had caused serious losses.They were not caused by fungi,bacteria or viruses.By loop-mediated isothermal amplification(LAMP)technique,the detection results pointed to the possible pathogen as phytoplasma.The investigation results implied that phytoplasmas could cause more than 13 kinds of symptoms in almost all parts of plants in B.napus L.,including witches’broom,multi-stems,aggregate main inflorescences,and flat stems.The incidences of these phytoplasma-associated diseases in our experimental farms rose from 1.61%in 2010 to 6.00%in 2021.Some phytoplasma infected plants died without any growing points.These studies would be helpful for detecting phytoplasmas diseases,selecting disease resistant germplasm and improving varieties with disease resistances in B.napus L.

Tensor perturbations from bounce inflation scenario in f(Q)gravity

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations therein.As is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW experiments.We discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation variable.The general form of the tensor power spectrum is obtained both for large as well as small scale modes.As a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation scenario.Moreover,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.