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As an efficient watermark attack method, geometric distortions destroy the synchronization between the watermark encoder and decoder. Local geometric distortion is a considerable challenge in the watermarking field. Although many geometric distortion resilient watermarking schemes have been proposed, few perform well against local geometric distortions, such as random bending attacks (RBAs). To address this problem, this paper proposes a novel watermark synchronization process and a corresponding watermarking scheme. In our scheme, the watermark bits are represented by random patterns. The message is encoded to obtain a watermark unit, and the watermark unit is flipped to generate a symmetrical watermark. Then, the symmetrical watermark is additively embedded into the spatial domain of the host image. In watermark extraction, we first obtain the theoretical mean-square error minimized estimation of the watermark. Then, an autoconvolution function is applied to this estimation to detect the symmetry and obtain a watermark unit map. According to this map, the watermark can be accurately synchronized, and then extraction can be performed. Experimental results demonstrate the excellent robustness of the proposed watermarking scheme to local geometric distortions, global geometric distortions, common image processing operations, and some kinds of combined attacks. [ABSTRACT FROM AUTHOR]

Background: Tumor‐infiltrating immune cells participate in the initiation and progression of prostate adenocarcinoma (PRAD). However, it is not fully known how immune infiltration affects the development of PRAD and its clinical presentation. Methods: Herein, we investigated the immune infiltration phenotypes in PRAD based on transcriptome profiles, methylation profiles, somatic mutation, and copy number variations. We also developed an immune prognostic model (IPM) to identify unfavorable prognosis. To verify this model, immunohistochemistry staining was performed on a cohort of PRAD samples. Moreover, we constructed a nomogram to assess the survival of PRAD incorporating immune infiltration and other clinical features. Results: We categorized PRAD patients into high and low‐level clusters based on immune infiltration phenotypes. The patients in the high‐level clusters had worse survival than their low‐level counterparts. Gene set enrichment analysis indicated that both anti‐ and pro‐tumor terms were enriched in high‐level cluster. Moreover, we identified a positive correlation between anti‐ and pro‐tumor immune cells in PRAD microenvironment. Notably, Somatic mutation analysis showed patients in high‐level cluster had a higher somatic mutation burden of KMT2D, HSPA8, CHD7, and MAP1A. In addition, we developed an IPM with robust predictive ability. The model can distinguish high‐risk PRAD patients with poor prognosis from low‐risk PRAD patients in both training and another three independent validation datasets. Besides, we constructed a nomogram incorporating Gleason score, pathological T stage, and IPM for the prognosis prediction of PRAD patients, which displayed robust predictive ability and might contribute to clinical practice. Conclusion: Our work illustrated the immune infiltration phenotypes strongly related to the poor prognosis of PRAD patients, and highlighted the potential of the IPM to identify unfavorable tumor features. [ABSTRACT FROM AUTHOR]

The genetic relationships of 45 individuals of Psidium guajava from six cultivars were analyzed by screening SSR primers with high polymorphism and good repeatability, which provided a scientific basis for the collection, protection, and utilization of guava germplasm resources in China. In this study, we analyzed genetic diversity and cluster of 45 guava materials using 15 pairs of polymorphic SSR primers. The number of polymorphic bands was 65 with the polymorphism ratio of 97.01%, and the molecular weight of the band ranges from 102 bp to 500 bp. Only two polymorphic bands were detected by primer mPgCIR23, which was the least. In contrast, primer mPgCIR08 detected seven bands with the highest number of polymorphic bands. The average polymorphism information content of the markers was 0.60, Nei's genetic diversity was 0.29, and Shannon's index was 0.44. Additionally, the variation range of genetic similarity coefficient was 0.37–0.99. The clustering pattern generated from the UPGMA method distinctly grouped the cultivated varieties and the seedling strain into four groups when the genetic similarity coefficient is 0.68. All the seedling strains (except S9) were successfully clustered into three subgroups, which confirmed that they were progenies from three different guava varieties, respectively. [ABSTRACT FROM AUTHOR]

• The design of the Core Assembly Deformation Test Facility was described in detail. • The conditions of assembly bending and thermal bowing tests were introduced briefly. • The heating and measurement technologies and the layout of sensors were introduced. China Demonstration Fast Reactor (CFR600) is under construction, and the Sub-assembly Deformation Analysis Program (SDAP) developed by China Institute of Atomic Energy is used to optimize the core design and operation management of CFR600. The Core Assembly Deformation Test Facility (CADTF), designed and built by Xi'an Jiaotong University, was selected to carry out a series of assembly bending and thermal bowing tests to provide validation problems for the SDAP. The specimen assembly was specially designed for better non-intrusive optical temperature measurement of the inner wrapper tube. The automatic heating control method and a lot of new measurement technology were applied into the tests to gain abundant and accurate test data. [ABSTRACT FROM AUTHOR]

Highlights • A new method was proposed to simulate thermal deformation of subassembly in SFR. • Assembly deformation analysis code FADAC was developed and applied in the present study. • Free bowing was analyzed under different temperature conditions and displacement field of the subassembly was obtained. • Restrained bowing was analyzed in detail and maximum deflection was calculated. Abstract Due to the special geometry and compact arrangement of subassemblies in the sodium-cooled fast reactor, thermal deformation of the assemblies are easily triggered by uneven temperature distribution in the reactor core, which is negative for reactor safety. Therefore, it is necessary for researchers and engineers to conduct quantitative analysis towards thermal deformation behaviors of subassemblies, and furthermore, give reliable evaluation results on aftermath of the assembly thermal deformation. In the present study, thermal deformation analysis code FADAC, which was developed based on Euler-Bernoulli beam theory, was applied to make numerical investigation for thermal deformation behaviors of a single subassembly in sodium-cooled fast reactor. In order to preliminarily assess the capacity for thermal deformation, different temperature gradient conditions were considered and analyzed in detail for free bowing of the subassembly, furthermore, with the aid of numerical analysis for thermal axial forces and thermal bending moments, axial displacements and deflections were calculated finally. Besides, in order to predict the comprehensive results of the assembly deformation under both thermal load and mechanical load, restrained bowing were also analyzed for different temperature conditions. All of the simulation results were in good accordance with the experimental data. The present numerical research is of great significance to assembly deformation research in the sodium-cooled fast reactor, and will surely lay a solid foundation for deformation analysis towards multi-subassemblies. [ABSTRACT FROM AUTHOR]

• Three-dimensional simulation (3D) of fuel relocation under loss-of-coolant accident is performed by using discrete element method. • The 3D simulation of fuel relocation is firstly validated by the in-pile experiments. • The critical parameters like fuel stack reduction, mass fraction and filling ratio are influenced by the mean diameter of fuel fragments. • The exponentially fitting correlations are proposed for the fuel stack reduction as a function of the relative cladding volume increase. • The exponentially fitting correlations are proposed for the mass fraction and filling ratio as a function of the cladding circumferential strain. This work presents the three-dimensional (3D) simulations of fuel relocation during loss-of-coolant accidents based on the coupled FEM-DEM approach. A simple equivalent approach is employed to generate the fragment geometry with the mean diameter as the fragment size measured in the sieve test. For the first time, the 3D simulation of fuel relocation is validated by the in-pile experiments performed in the FR2 research reactor. The predicted missing fuel length is in good agreement with the experimental data, indicating the viability and effectiveness of the simulation. According to the features of fuel relocation, the parametric study on fragment mean diameter and cladding volume increase is conducted. Based on the quantitative analysis, it is found that the fuel stack reduction exponentially increases with the relative cladding volume increase. Also, the mass fraction and the filling ratio seem to exponentially increase and decrease with cladding circumferential strain, respectively. A series of fitting correlations of fuel stack reduction, mass fraction and filling ratio are proposed for different fragment mean diameters. By implementing the empirical correlation of filling ratio, the capability of the one-dimensional model is improved to gain a close predicted result as 3D simulation. The proposed correlations can support the interpretation of experimental data, and can enhance the evaluation accuracy of fuel performance during loss-of-coolant accidents by the more realistic prediction of the critical parameters influenced by fuel relocation. [ABSTRACT FROM AUTHOR]

• Equilibrium equations and compatibility equations were conducted respectively to consider coupling effects of subassemblies in SFR. • Calculation for row bowing was performed with the aid of FADAC code in the present study. • Row bowing was analyzed in detail under different geometric parameters for wrapper tube, even core baffle was taken into consideration. • Reaction forces and deflection parameters were obtained by calculation, which are meaningful for safety evaluation and core structural design. Subassemblies in sodium-cooled fast reactor are different from pressurized water reactor in both geometry and assembly arrangement. In sodium-cooled fast reactor, assembly thermal deformation and narrow clearance between adjacent assemblies would cause them contact with each other, and reaction force between neighboring pads would occur. Under that circumstance, assembly deformation would be decided by both thermal load and mechanical load, which means significant coupling effect would lead to more complicated deformation behaviors. Therefore, so as to deeply study such thermal–mechanical coupling effect in reactor core, it is meaningful to conduct theoretical analysis and numerical simulation on such behaviors, which is indispensable for reactor safety analysis and structural design. In the present study, equilibrium equations and compatibility equations were conducted respectively for acquiring deformation parameters of assemblies in the row, which were already implemented into FADAC code and can perform calculation for row bowing. Furthermore, reaction forces and assembly deflections were analyzed in detail. Besides, sensitivity analysis were performed for row bowing calculation, in which wrapper tube thickness, distance across flat for wrapper tube, pad clearance and effects of core baffle were all taken into consideration. The present theoretical research for assembly deformation in SFR is essential for reactor safety and structural design, and will lay a solid foundation for assembly deformation analysis in the whole core. [ABSTRACT FROM AUTHOR]

• Behavior of Cr-coated clad under integral LOCA test is simulated in FEA. • Current burst criteria for Zircaloy is ineffective to capture Cr-coated concept. • New overstress and plasticity instability criteria for the Cr coating are proposed. • Coating thickness is found to be numerically insensitive to burst temperature. Chromium (Cr) coated cladding is one of the most promising accident-tolerant fuels for pressurized water reactors. The behavior of Cr-coated cladding under the accident conditions is crucial to quantify its implication on safety, licensing and economics. This work focuses on the modeling of the burst behavior of Cr-coated cladding under Loss of Coolant Accidents (LOCAs). For this purpose, the material properties and behavior models of Zircaloy and chromium have been studied and implemented into the ABAQUS. Then the ABAQUS models are compared against several burst tests done by Korea Atomic Energy Research Institute (KAERI) and Électricité de France (EDF). During the comparison process, different high temperature creep models, zircaloy cladding burst criteria and coating thicknesses are adopted to investigate the thermo-mechanical performance and burst behavior of Cr-coated claddings under LOCA. Based on the comparative computational analysis, 100% and 85% Cr fracture strength and the strain rate of 0.23 /s and 0.07 /s are proposed as a new overstress burst criterion for coated cladding under a heating rate from 5 K/s and 10 K/s. The effect of coating thickness on the proposed criteria and the ballooning behavior of the coated cladding was predicted to be insignificant. The proposed criteria are beneficial for better understanding of the coated clad burst phenomena and the best estimation of coated clad performance under LOCA scenarios. [ABSTRACT FROM AUTHOR]

Under normal operation, oxide nuclear fuel pellets subjected to high thermomechanical loading and irradiation damage can develop complex crack networks, separating the fuel pellet into a pile of fragments. During a Loss of Coolant Accident (LOCA), these pellet fragments, or fine powder especially when originating from the high-burnup fuel pellet periphery, may relocate axially into the ballooned region of the zircaloy cladding. In this work, the axial relocation process of fuel fragments and powder is modeled based on the three-dimensional Discrete Element Method (DEM) in the Abaqus software. A Voronoi tessellation technique is adopted to generate random convex polyhedrons in order to mimic a coarse fragmentation pattern. A parametric study in terms of the mean fragment size from 1.3 mm to 3.0 mm was conducted to investigate its effect on the axial profile of fuel mass fraction and filling ratio after fuel relocation. Then a sensitivity study of the randomness in fragmentation on axial fuel relocation was performed. For high-burnup fuels, in order to characterize the porous High Burnup Structure (HBS), the pellet rim was discretized into separate spherical shape particles. The effect of powder fraction on fuel relocation was demonstrated, and the results indicated that higher powder fraction can significantly increase the fuel mass fraction and filling ratio level in the ballooned region, which showed qualitative agreement with experimental observations. Finally, the verification against a one-dimensional theoretical relocation model was conducted to verify the robustness and high fidelity features of the DEM model in simulating axial fuel relocation under LOCA. The modeling approach serves as a mechanistic framework to support future burnup extensions for the oxide nuclear fuel. [ABSTRACT FROM AUTHOR]

• The assembly compression test was described, and the section stiffness were given. • The assembly bending test was described, and the bending stiffness were given. • Compared and discussed the data of the IAEA benchmark tests and the XJTU tests. China Fast Reactor (CFR) is under construction, and the section stiffness and bending stiffness of CFR assemblies remain unknown and need to be investigated to support the core restraint system design and reactivity safety assessment. In this study, assembly compression tests were performed with three types of test samples. With the compression load varying from 0 to 6 kN, the compressive deformations were measured and the section stiffness were obtained. In assembly bending tests, there were two types of assemblies considering different spike clearances, and the horizontal loads from 400 N to 1900 N were applicable to the upper-load-pad, lower-load-pad and mid-fissile-region level of the assemblies. Assembly deflections were measured and correlations for the load-deflection ratio were proposed. Comparison of theoretical and experimental bending stiffness were carried out, which indicated that the spike clearance has to be taken into consideration in the assembly deformation analysis codes. [ABSTRACT FROM AUTHOR]

mRNA‐based molecular subtypes have implications for bladder cancer prognosis and clinical benefit from certain therapies. Whether small extracellular vesicles (sEVs) can reflect bladder cancer molecular subtypes is unknown. We performed whole transcriptome RNA sequencing for formalin fixed paraffin embedded (FFPE) tumour tissues and sEVs separated from matched tissue explants, urine and plasma in patients with bladder cancer. sEVs were separated using size‐exclusion chromatography, and characterized by transmission electron microscopy, nano flow cytometry and western blots, respectively. High yield of sEVs were obtained using approximately 1 g of tissue, incubated with media for 30 min. FFPE tumour tissue and tumour tissue‐derived sEVs demonstrated good concordance in molecular subtype classification. All urinary sEVs were classified as luminal subtype, while all plasma sEVs were classified as Ba/Sq subtype, regardless of the molecular subtypes indicated by their matched FFPE tumour tissue. The comparison within urine sEVs, which may exclude the sample type specific background, could pick up the different biology between NMIBC and MIBC, as well as the signature genes related to molecular subtypes. Four candidate sEV‐related bladder cancer‐specific mRNA biomarkers, FAM71E2, OR4K5, FAM138F and KRTAP26‐1, were identified by analysing matched urine sEVs, tumour tissue derived sEVs, and adjacent normal tissue derived sEVs. Compared to sEVs separated from biofluids, tissue‐derived sEVs may reflect more tissue‐ or disease‐specific biological features. Urine sEVs are promising biomarkers to be used for liquid biopsy‐based molecular subtype classification, but the current algorithm needs to be modified/adjusted. Future work is needed to validate the four new bladder cancer‐specific biomarkers in large cohorts. [ABSTRACT FROM AUTHOR]

This paper designs a novel underpainting based camera shooting resilient (CSR) document watermarking algorithm for dealing with the leak source tracking problem. By applying such algorithm, we can extract the authentication watermark information from the candid photographs. The watermarked underpainting contains three significant properties. 1) Inconspicuousness. The watermarked underpainting is inconspicuous and it will not easily be maliciously attacked. 2) Robustness. We propose DCT-based watermark embedding algorithm and distortion compensation based extracting algorithm, which make the watermark robust to camera shooting process. 3) Autocorrelation. We design the flip-based method to arrange the watermarked underpainting. So that a complete watermark region can be accurately located even if part of the document is recorded. Compared with previous watermarking algorithms, the proposed scheme guaranteed content independent embedding as well as the robustness to the camera shooting process. Besides, the proposed scheme satisfies the accuracy of extraction even when the captured document is incomplete. [ABSTRACT FROM AUTHOR]

With the development of technology, the application of intelligent coal gangue sorting is more and more favored by coal mining enterprises. The coal gangue intelligent sorting system has higher requirements on the coal conveyor belt. The traditional transmission system has the problems of slow speed response, unstable operation, high energy consumption and jitter in the process of speed change. Using PLC, touch screen, frequency converter, RS-485, sensors and so on, the speed control and speed monitoring system of belt transport mechanism is constructed. By analyzing the error law of the system speed control and using Numpy system analysis and calculation, speed pre-compensation can be made. Then by controling speed precision through the PID and monitoring display through the time-speed curve, the real-time automation gives an alarm for abnormal speed situation. According to the speed requirement of the intelligent sorting system of coal gangue, the system can quickly reach the predetermined speed value, and effectively eliminate the shaking phenomenon in the process of changing speed. The system has strong universality, easy maintenance, and stable speed control, which is conducive to improving the reliability and efficiency of the intelligent sorting system for coal gangue and reduceing transmission mechanism wear caused by dithering. [ABSTRACT FROM AUTHOR]

As an important part of the new infrastructure, the cloud data center is developing rapidly, and its energy consumption problem is becoming more and more prominent. Therefore, research on energy-saving technologies for cloud data centers has attracted widespread attention from academia and industry. Some studies have reviewed energy-saving optimization methods and technologies for data centers, but recently, many state-of-the-art optimization methods of energy consumption and energy-saving technologies have sprung out, which are still worth analyzing and discussing. Depending on the in-depth investigation and analysis of related research status, this article firstly focuses on analyzing and discussing the energy-saving technologies of the two components: IT equipment and cooling systems, both of which bring about the largest energy consumption in cloud data centers. As for IT equipment, its energy-saving technologies mainly include the energy saving of servers, storage systems, and network systems. While as for cooling systems, airflow organization in the computer room, thermal-aware scheduling technology, and other new energy-saving technologies are involved. Secondly, on the basis of analyzing the energy-saving technologies of the two major components, a new optimization scheme of energy consumption for the jointing computing system and cooling system is explained. Throughout this work, various energy-saving strategies and technologies have been described and compared. Finally, the future trends and development directions of energy saving for data centers are further promoted, such as integral optimization of energy consumption jointing multiple components, energy saving using artificial intelligence methods, energy saving based on novel hardware equipment, hybrid cooling energy saving, and comprehensive energy conservation with various energy technologies. [ABSTRACT FROM AUTHOR]

Traditional watermarking algorithms have been extensively studied. As an important type of watermarking schemes, template-based approaches maintain a very high embedding rate. In such scheme, the message is often represented by some dedicatedly designed templates, and then the message embedding process is carried out by additive operation with the templates and the host image. To resist potential distortions, these templates often need to contain some special statistical features so that they can be successfully recovered at the extracting side. But in existing methods, most of these features are handcrafted and too simple, thus making them not robust enough to resist serious distortions unless very strong and obvious templates are used. Inspired by the powerful feature learning capacity of deep neural network, we propose the first deep template-based watermarking algorithm in this paper. Specifically, at the embedding side, we first design two new templates for message embedding and locating, which is achieved by leveraging the special properties of human visual system, i.e., insensitivity to specific chrominance components, the proximity principle and the oblique effect. At the extracting side, we propose a novel two-stage deep neural network, which consists of an auxiliary enhancing sub-network and a classification sub-network. Thanks to the power of deep neural networks, our method achieves both digital editing resilience and camera shooting resilience based on typical application scenarios. Through extensive experiments, we demonstrate that the proposed method can achieve much better robustness than existing methods while guaranteeing the original visual quality. [ABSTRACT FROM AUTHOR]

• A font-based text watermarking scheme is proposed to achieve robustness to cross-media distortions such as print-camera shooting, screen-camera shooting, and print-scanning. • A glyph centroid modification-based font codebook generation algorithm is proposed to automatically create target-similar fonts. • The proposed method does not require the participation of OCR to identify glyphs, which can improve the extraction accuracy and efficiency. • The proposed method is applicable with various font sizes, languages, and devices. The rapid development of digital devices and the increasing demand for copyright protection and leakage tracing of documents result in new demands for robust text watermarking. It becomes more important for a utility text watermarking scheme to have robustness in cross-media channels since the camera shooting operation to papers or screens has become very convenient. To achieve the corresponding cross-media robustness, this paper proposes a font-based text watermarking scheme, which is applicable to most commonly used languages while the previous works were usually designed for specific languages. To generate fonts with high efficiency, we propose a novel glyph centroid modification-based font generation algorithm, which can automatically create target-similar fonts. And we design an effective watermarking scheme that utilizes the relative centroid position (RCP) of glyphs to represent watermark signals. Compared with existing font-based text watermarking schemes that artificially design fonts, the proposed scheme ensures higher efficiency by generating the font codebook automatically. In addition, the proposed RCP-based watermarking scheme can achieve the robustness against lossy compression and several kinds of cross-media distortions. The watermark message can be extracted without the need to recognize the semantic information of glyphs by optical character recognition (OCR). [ABSTRACT FROM AUTHOR]

Serine hydroxymethyltransferase 2 (SHMT2) is a key enzyme that regulates serine/glycine transition; however, its specific function and molecular mechanisms in tumors remain controversial. In this study, we aimed to enhance the understanding in this regard. Through in vitro and in vivo experiments, as well as data analyses using public databases, we investigated the effect of SHMT2 in prostate cancer. Our results indicated that SHMT2 acts as a prostate cancer tumor proliferation suppressor and negatively regulates the aggressive behavior of prostate cancer through activation of epithelial–mesenchymal transition. Additionally, downregulated SHMT2 expression was observed in more advanced prostate cancer phenotypes, and further analysis showed that its depletion promoted proliferation and migration in prostate cancer cell lines. Taken together, our results revealed the function of SHMT2 in prostate cancer and may potentially play a role in the exploration of new therapeutic strategies. [ABSTRACT FROM AUTHOR]