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SIoT enables devices to communicate with each other automatically, which is not reliable when applications in SIoT are vulnerable. To improve the security of SIoT, different techniques have been employed so far, mainly to detect vulnerabilities in SIoT applications. Among the detection techniques, fuzzing is one of the most effective ones that can significantly improve the security of SIoT applications. However, the existing fuzzing methods have three problems. First of all, the schemes to instrument target binaries cause high memory overhead because they instrument at all edges to obtain the coverage information. Moreover, they introduce a severe problem called edge collision, i.e., two different edges are deemed the same during fuzzing. Thirdly, none of the existing fuzzers conduct fuzzing using path coverage because path coverage has high memory overhead. In this paper, we propose BECFuzz to resolve the above three problems. BECFuzz instruments at specific edges, and conducts fuzzing based on both edge coverage and path coverage, which greatly improves its effectiveness. We implement our BECFuzz based on two typical fuzzers which are widely recognised as baselines, AFL and AFLFast, and run experiments on 18 real-world programs. The results demonstrate that our method suppresses the state-of-art fuzzers in performance.

Fuzz testing (fuzzing) has witnessed its prosperity in detecting security flaws recently. It generates a large number of test cases and monitors the executions for defects. Fuzzing has detected thousands of bugs and vulnerabilities in various applications. Although effective, there lacks systematic analysis of gaps faced by fuzzing. As a technique of defect detection, fuzzing is required to narrow down the gaps between the entire input space and the defect space. Without limitation on the generated inputs, the input space is infinite. However, defects are sparse in an application, which indicates that the defect space is much smaller than the entire input space. Besides, because fuzzing generates numerous test cases to repeatedly examine targets, it requires fuzzing to perform in an automatic manner. Due to the complexity of applications and defects, it is challenging to automatize the execution of diverse applications. In this article, we systematically review and analyze the gaps as well as their solutions, considering both breadth and depth. This survey can be a roadmap for both beginners and advanced developers to better understand fuzzing.

Solid-state lithium batteries (SSLBs) have been identified as one kind of the most promising energy conversion and storage devices because of their safety, high energy density, and long cycling life. The development of solid-state electrolyte is vital to commercialize SSLBs. Composite polymer electrolyte (CPE), derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical properties. The characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE, improving its ionic conductivity, mechanical properties, thermal and electrochemical stability, as well as interface compatibility with both electrodes. In this review, the effects of particle characteristics including its species, size, proportion, morphology on the ionic conductivity and mechanical properties of CPE are reviewed. Meanwhile, some novel composite strategies are also introduced including surface modification, hybridization, and alignment of particles in polymer matrices, as well as some new preparation methods of CPE. The interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive mechanism. Finally, a perspective on the direction of future CPE development for SSLBs is presented.

This study investigated the microstructures and tensile properties of as-build and heat-treated (including T6, T2 and T6-T2 treatments) AlSi10Mg samples fabricated by laser powder bed fusion (LPBF). The microstructure analysis revealed that the trend of eutectic Al-Si phase distribution along grain boundaries for heat-treated samples was significantly weakened, and the eutectic Al-Si phase was transformed into Si particles which were uniformly distributed in α-Al matrix. For the T6-T2 treated specimens, the Si content in particles was the highest. Meanwhile, the T6 treatment increased the proportion of equiaxed grains on vertical section most significantly. However, in the wake of heat treatments, the average grain size on horizontal section had little change while the average grain size on vertical section was increased. The properties analysis demonstrated that the T6-T2 treated specimens obtained the best elongation and worst strength. Besides, the T6 treatment eliminated the anisotropy of the LPBFed specimens basically, and synergistically obtained the best combination of strength and plasticity. The T6 treatment weakened the direction difference to the greatest extent, whereas the T2 treatment minimized the stress concentration. According to the comparative finding, the Si content in particles played an important part in properties. Besides, the relationship among inverse pole figure (IPF) maps, pole figure (PF) maps, the mass fraction and distribution of Si in Al matrix and Si particle, the grain size, Kernel average misorientation (KAM) and mechanical properties under different heat treatments was established, which provided a new idea for the selection of heat treatments on LPBFed parts.

Cardiomyopathy comprises a heterogeneous group of myocardial abnormalities, structural or functional in nature, in the absence of coronary artery disease and other abnormal loading conditions. These myocardial pathologies can result in premature death or disability from progressive heart failure, arrhythmia, stroke, or other embolic events. The European Cardiomyopathy Registry reports a high stroke risk in cardiomyopathy patients ranging from 2.1% to 4.5%, as well as high prevalence of atrial fibrillation ranging from 14.0% to 48.5%. There is a growing interest in evaluating the risk of thromboembolism depending on the type of cardiomyopathy, as well as if anticoagulation is indicated in patients with cardiomyopathy without atrial fibrillation. Data available do not unequivocally support anticoagulation therapy in all of these patients; the management of these patients remains challenging. Many published reports pertaining to the risk of thromboembolism and consecutive treatment strategies mainly focus on single cardiomyopathy subtype. We summarize essential pathophysiological knowledge and review current literature associated with thromboembolism in various cardiomyopathy subtypes, providing recommendations for the diagnostic evaluation as well as clinical management strategies in this field. Certain cardiomyopathy subtypes require anticoagulation independent of atrial fibrillation or CHA2DS2‐VASc score. Despite the scarcity of evidence regarding the choice of anticoagulation regimen (vitamin K antagonist vs. non‐vitamin K oral anticoagulants) in cardiomyopathy, it is discussed and reviewed in this article. Each patient should receive a tailored strategy based on thorough clinical evaluation, published evidence, and clinical experience, due to the current recommendations mostly developed on small‐sample studies or empirical evidence. The future research priorities in this area are also addressed in this article.

The mathematical models built based on space-fractional derivatives adequately describe the phenomena incorporating spatial heterogeneity, but their numerical simulation on general domains remains a difficult issue. In this study, we develop a local differential quadrature (DQ) formula based on radial basis functions (RBFs) to discretize Riesz fractional derivatives, which is defined by the functional values at the nodes located in the subdomain around the discrete node. The proposed formula overcomes the drawback of ill-conditioning associated with the global DQ method and enables us to approximate the fractional derivatives on irregular domain with high flexibility and good accuracy. Applying this local DQ formula in space and using weighted average (WA), predictor-corrector (PC) difference schemes in time, we then construct two linearized local RBFs-based DQ schemes for the two-dimensional nonlinear Riesz space-fractional advection-diffusion equations (ADEs). The validity of this local DQ formula is confirmed by numerical results. The feasibility and capability of both local RBFs-based DQ schemes are authenticated by the illustrative tests on some irregular domains and the numerical simulation of Gaussian pulse propagation.

IoT devices usually have resource limitations and are prone to compromise. They are not well equipped with extra controls to promote their security. Green IoT (GIoT) devices are even more conservative in spending their resources. An effective way of promoting GIoT security at a low cost is removing program vulnerabilities. Fuzzing is a promising technique that exposes bugs in IoT programs. To evaluate a fuzzer performance, we make it run the test programs from some corpora to show its ability in detecting bugs. However, the contexts of bugs are not provided by the existing corpora, which may mislead the evaluation. Due to the complex logic of real-world programs, especially the GIoT ones, it is hard to obtain the bugs context. In this research, we propose to synthesize programs based on road-rock features that protect bugs from being exposed. Accordingly, we design a framework to generate a corpora that provide us with the contexts of bugs for more comprehensive fuzzing evaluation. As a case study, we evaluate AFL and AFLFast by using the synthesized corpora. The results show that AFLFast has the weakness of cycle explosion , which prevents fuzzing from examining more test cases. We developed AFLFast+ to overcome this issue.

To evaluate the effectiveness of high-intensity focused ultrasound (HIFU) combined with hysteroscopy-guided suction curettage (HGSC) in treating cervical pregnancy.This is a retrospective study. Seven patients with cervical pregnancy who visited the Third Xiangya Hospital of Central South University from January 2015 to December 2020 were enrolled in the current study. All seven patients were treated with HIFU under conscious sedation. All of them underwent HGSC at an average of 2 ± 1 days (range: 1-3 days) after HIFU. Before the therapy, the patient's clinical characteristics were collected, including duration of amenorrhea, gravidity and parity, the patient history of cesarean section and miscarriage, and the size of the gestational sac. The levels of β-hCG and hemoglobin in serum were also reviewed. To assess the clinical outcomes of this combined treatment, the suction time of HGSC, bleeding volume, the clearance time of β-hCG, and the time with returning of menstruation were evaluated.All seven patients (average age: 31 ± 6 years) have experienced amenorrhea (duration range, 48 ± 8 days) before the treatment of HIFU. The average number of pregnancies was four, and the number of deliveries was one. Previous medical history showed six patients had cesarean sections, and five patients have been miscarriages. After HIFU treatment, the fetal heartbeats were stopped in all seven patients based on the diagnosis by doppler ultrasound. The bleeding of gestational tissue decreased significantly. All patients had only mild lower abdominal pain, no fever, intestinal damage, or other complications were reported. The average operation time of operative suction curettage was 21 ± 9 min (range: 9-32 min), and the median bleeding volume was 10 ± 8 mL (range: 2-20 mL). Follow-up observations showed that the menstruations were returned in patients at an average of 38 ± 9 days (range: 30-50 days) after the treatment. The β-hCG decreased from 41773 ± 32242 mIU/mL to 13101 ± 8454 mIU/mL in 29 ± 10 days after surgery.Based on these results with small subjects, we concluded that HIFU combined with HGSC might be an effective and safe treatment for patients with cervical pregnancy.

Images play an important role in transmitting visual information in our life. It could lead to severe consequences if images are manipulated or tampered maliciously. Digital forensics is an important research area to secure multimedia information. Many forensics technologies are applied to protect our community from the abuse of digital information. In many cases, after tampering, attackers could apply operations such as resampling, JPEG compression, blurring, etc. to cover the traces of tampering. Therefore, it is necessary to detect these manipulations in image forensics before exposing forgeries. In this paper, we propose to employ the prediction error filters, ConvNeXt blocks and convolution modules to classify images with different compression quality factors and resampling rates. By tracing the inconsistencies of resampling rates and compression quality factors, it could provide supplementary information for forensics researchers to expose possible forgeries. The proposed method could achieve great classification performance regardless of the interpolation algorithms. Also, it is highly robust against JPEG compression. In addition, the proposed method can be applied for estimating quality factors of JPEG compression.

Background Ovarian cancer cells show resistance to platinum drugs treatment, which brings a big challenge to clinical therapeutics. This study aimed to construct effective drug delivering nanoparticles specifically targeting ovarian cancer cell. Methods Poly lactic-co-glycolic acid (PLGA) were used to form Nano-spheres by double emulsion method, and to deliver CPT-11. Connected with targeted LHRH-a molecules, their effects were tested by ovarian cancer cell A2780/DDP in vitro and in vivo. Results We successfully constructed PLGA nanoparticles carrying LHRH-a (Luteinizing hormone releasing hormone analogue) and CPT-11 (irinotecan HCl trihydrate), which can specifically target LHRH receptor high expression ovarian cancer cell A2780/DDP (cisplatin). Combined with focused ultrasound in vitro, LHRH-a/CPT-11/PLGA nanoparticles significantly inhibited the proliferation of A2780/DDP cells (a cisplatin-resistant A2780 cell line), and the cells were obviously arrested at S phase. Both the mRNA expression and protein level of Caspase3 increased, while Bcl-2 and MMP2 declined, which promoted apoptosis. In vivo, LHRH-a/CPT-11/PLGA nanoparticles bind specifically with LHRH receptor on xenograft tumors of A2780/DDP. With focused ultrasound, LHRH-a/CPT-11/PLGA nanoparticles inhibited the growth of A2780/DDP xenograft tumors significantly. The expression level of VEGF, Bcl-2 and MMP2 reduced, while Caspase3 increased in tumors. Conclusions CPT-11 delivering PLGA nanoparticles with LHRH-a specifically target ovarian cancer cell A2780/DDP, and work locally when combined with focused ultrasound. They increase local drug concentration and reduce side effects. This research may provide a new effective therapeutic strategy for recurrent platinum resistant ovarian cancer.

Coverage-guided Greybox Fuzzing (CGF) is one of the most successful and widely-used techniques for bug hunting. Two major approaches are adopted to optimize CGF: (i) to reduce search space of inputs by inferring relationships between input bytes and path constraints; (ii) to formulate fuzzing processes (e.g., path transitions) and build up probability distributions to optimize power schedules, i.e., the number of inputs generated per seed. However, the former is subjective to the inference results which may include extra bytes for a path constraint, thereby limiting the efficiency of path constraints resolution, code coverage discovery, and bugs exposure; the latter formalization, concentrating on power schedules for seeds alone, is inattentive to the schedule for bytes in a seed. In this paper, we propose a lightweight fuzzing approach, Truzz, to optimize existing Coverage-guided Greybox Fuzzers (CGFs). To address two aforementioned challenges, Truzz identifies the bytes related to the validation checks (i.e., the checks guarding error-handling code), and protects those bytes from being frequently mutated, making most generated inputs examine the functionalities of programs, in lieu of being rejected by validation checks. The byte-wise relationship determination mitigates the problem of loading extra bytes when fuzzers infer the byte-constraint relation. Furthermore, the proposed path transition within Truzz can efficiently prioritize the seed as the new path, harvesting many new edges, and the new path likely belongs to a code region with many undiscovered code lines. The experimental results show that on average, Truzz can generate 16.14% more inputs flowing into functional code, in addition to 24.75% more new edges than the vanilla fuzzers. Finally, our approach exposes 13 bugs in 8 target programs, and 6 of them have not been identified by the vanilla fuzzers.

In this article, an advanced differential quadrature (DQ) approach is proposed for the high-dimensional multi-term time-space-fractional partial differential equations (TSFPDEs) on convex domains. Firstly, a family of high-order difference schemes is introduced to discretize the time-fractional derivative and a semi-discrete scheme for the considered problems is presented. We strictly prove its unconditional stability and error estimate. Further, we derive a class of DQ formulas to evaluate the fractional derivatives, which employs radial basis functions (RBFs) as test functions. Using these DQ formulas in spatial discretization, a fully discrete DQ scheme is then proposed. Our approach provides a flexible and high accurate alternative to solve the high-dimensional multi-term TSFPDEs on convex domains and its actual performance is illustrated by contrast to the other methods available in the open literature. The numerical results confirm the theoretical analysis and the capability of our proposed method finally., Comment: 22 pages, 26 figures

To ensure the stability of precision of the motorized spindle for five-axis machining center, the thermal error of five-axis machining center was investigated, and the temperature rise-thermal deformation model of a thin-wall ring type rotary elastomer was built on the basis of thermo-elastic property. Thus, a model of radial thermal error was con-structed. The relationship between radial error and axial error was also investigated in this paper and the total radial errors were gotten. In addition, the thermal error of the motorized spindle of five-axis machining center was measured by the ball bar in the experiment of thermal error. The motorized spindle total radial error was achieved by this experiment and radial total error analytical model. Finally, a BP neural network algorithm was introduced for thermal error prediction of five-axis machining center, and the precision of prediction of these models was compared and analyzed. The analysis shows that this method is practical and effective.

The change in plasma apelin level in heart failure (HF) patients is controversial. We investigated the change in plasma apelin level in HF patients versus control and non-HF patients. The plasma level of apelin was measured by ELISA and plasma level of B-type natriuretic peptide (BNP) by fluorescence immunoassay. We included 101 patients with HF, 32 patients without HF and 20 controls. The three groups did not differ in general and clinical characteristics. Plasma levels of apelin and BNP were both higher in HF patients than non-HF patients and controls. Plasma levels of apelin and BNP were not correlated. Plasma level of BNP was increased with increasing New York Heart Association grade and apelin level was decreased. Apelin level was lower in HF patients with NYHA grade IV than in controls and non-HF patients. Apelin level had 75% diagnostic value for HF, and BNP level had 96.8% diagnostic value. At a cutoff of 6.44 ng/mL apelin level, sensitivity was 69.3%, and specificity 97.1%. However, the diagnostic of apelin for NYHA II patients was higher than that of BNP (99.6% vs. 96.1%). These results suggested that apelin might be particularly useful in association with BNP in mild HF patients.

High-dimensional space-fractional PDEs are topics of special focus in applied disciplines, but solving them on irregular domains is challenging and deserves particular attention in scientific computing. In response to this issue, we establish a family of differential quadrature (DQ) methods for the space-fractional diffusion equations on 3D irregular domains. The fractional derivatives in space are represented by weighted linear combinations based on the functional values at scattered nodes with their weights determined by using radial basis functions (RBFs) as trial functions. The resulting system of ordinary differential equations (ODEs) are discretized by the weighted average scheme. The presented DQ methods have the virtues which are shared by the classical DQ methods. Several benchmark problems on typical irregular domains are solved to illustrate their advantages in flexibility and accuracy.

The proliferation of Internet of Things (IoT) devices has made people's lives more convenient, but it has also raised many security concerns. Due to the difficulty of obtaining and emulating IoT firmware, the black-box fuzzing of IoT devices has become a viable option. However, existing black-box fuzzers cannot form effective mutation optimization mechanisms to guide their testing processes, mainly due to the lack of feedback. It is difficult or even impossible to apply existing grammar-based fuzzing strategies. Therefore, an efficient fuzzing approach with syntax inference is required in the IoT fuzzing domain. To address these critical problems, we propose a novel automatic black-box fuzzing for IoT firmware, termed Snipuzz. Snipuzz runs as a client communicating with the devices and infers message snippets for mutation based on the responses. Each snippet refers to a block of consecutive bytes that reflect the approximate code coverage in fuzzing. This mutation strategy based on message snippets considerably narrows down the search space to change the probing messages. We compared Snipuzz with four state-of-the-art IoT fuzzing approaches, i.e., IoTFuzzer, BooFuzz, Doona, and Nemesys. Snipuzz not only inherits the advantages of app-based fuzzing (e.g., IoTFuzzer, but also utilizes communication responses to perform efficient mutation. Furthermore, Snipuzz is lightweight as its execution does not rely on any prerequisite operations, such as reverse engineering of apps. We also evaluated Snipuzz on 20 popular real-world IoT devices. Our results show that Snipuzz could identify 5 zero-day vulnerabilities, and 3 of them could be exposed only by Snipuzz. All the newly discovered vulnerabilities have been confirmed by their vendors., Accepted to ACM CCS 2021

What you change is what you fuzz! In an empirical study of all fuzzer-generated bug reports in OSSFuzz, we found that four in every five bugs have been introduced by recent code changes. That is, 77% of 23k bugs are regressions. For a newly added project, there is usually an initial burst of new reports at 2-3 bugs per day. However, after that initial burst, and after weeding out most of the existing bugs, we still get a constant rate of 3-4 bug reports per week. The constant rate can only be explained by an increasing regression rate. Indeed, the probability that a reported bug is a regression (i.e., we could identify the bug-introducing commit) increases from 20% for the first bug to 92% after a few hundred bug reports. In this paper, we introduce regression greybox fuzzing (RGF) a fuzzing approach that focuses on code that has changed more recently or more often. However, for any active software project, it is impractical to fuzz sufficiently each code commit individually. Instead, we propose to fuzz all commits simultaneously, but code present in more (recent) commits with higher priority. We observe that most code is never changed and relatively old. So, we identify means to strengthen the signal from executed code-of-interest. We also extend the concept of power schedules to the bytes of a seed and introduce Ant Colony Optimization to assign more energy to those bytes which promise to generate more interesting inputs. Our large-scale fuzzing experiment demonstrates the validity of our main hypothesis and the efficiency of regression greybox fuzzing. We conducted our experiments in a reproducible manner within Fuzzbench, an extensible fuzzer evaluation platform. Our experiments involved 3+ CPU-years worth of fuzzing campaigns and 20 bugs in 15 open-source C programs available on OSSFuzz.

Purpose This study aimed to analyze existing problems in the dissemination and management of emergency information on social media platforms, improve social media users' experience regarding such information, increase the efficiency of emergency information dissemination and curb the spread of misinformation. Design/methodology/approach In this study, the emergency information quality on social media platforms was examined. Based on the evaluation principles of the quality of mature information, social media information characteristics and the rules of emergency information dissemination, combined with relevant academic research results, an index to evaluate the quality of emergency information on social media was constructed. In addition, the authors have introduced cloud theory as an information quality evaluation method and used social media users' emotional characteristics to assess information quality evaluation results. A comprehensive system for evaluating emergency information quality, including indexes, methods and detection strategies was established. Based on a comprehensive system, a case study was conducted on the forest fires in Sichuan Province and the African swine fever events as reported on the Zhihu platform. In accordance with the results of the case study, the authors expanded the research and introduced the emotional characteristics of social media users as an independent evaluation dimension to evaluate the quality of emergency information on social media. Findings The comprehensive system's effectiveness was verified through the case study. Further, it was found that users' emotional characteristics (reflected in their information behavior) are inconsistent with their evaluation of websites' information quality regarding major emergencies. Integrating users' emotional characteristics into the information evaluation system can enhance its effectiveness following major emergencies. Originality/value First, an evaluation index system of emergency information quality on social media about major emergencies was offered. Unlike the commonly available index system for information quality evaluation, this proposed evaluation index system not only accounted for the characteristics of social media, such as massive disordered information, multiple information sources and rapid dissemination, but also for the characteristics of emergency events, such as variability and the absence of precursors. This proposed evaluation index system enhances the pertinence of the information quality evaluation and compensates for the shortcoming that the current research only focuses on evaluating social media information quality in a broad context, but pays insufficient attention to major emergencies. Second, cloud theory was introduced as a method to evaluate the emergency information quality found on social media. Existing research has primarily included the use of traditional statistical methods, which cannot transform numerical values into qualitative concepts effectively. Various indeterminate factors inevitably affect the quality of emergency information on social media platforms, and the traditional methods cannot eliminate this uncertainty in the evaluation process. The method to assess emergency information quality based on cloud theory can effectively compensate for the gaps in the research and improve the accuracy of information quality assessment. Third, the inspection and the dynamic adjustment of assessment results are absent in the research on information quality assessment, and the research has relied principally on the information users' evaluation and has paid insufficient attention to their attitudes and behaviors toward information. Therefore, the authors incorporated users' emotional characteristics into the evaluation of emergency information quality on social media and used them to test the evaluation results so that the results of the information quality assessment not only include the users' explicit attitudes but also their implicit attitudes. This enhances the effectiveness of the information quality assessment system. Finally, through this case study, it was found that an inconsistency exists between user evaluation and user emotional characteristics after major emergencies. The reasons for this phenomenon were explained, and the necessity of integrating user emotional characteristics into information quality assessment was demonstrated. Based on this, the users' emotional characteristics were used as a separate evaluation dimension for assessing the quality of emergency information on social media. Compared with assessing the quality of general information, integrating the user's emotional characteristics into the evaluation index system can lead the evaluation results to include not only the users' cognitive evaluation but also their emotional experience, further enhancing their adaptability.

A 4H-SiC trench gate metal–oxide–semiconductor field-effect transistor (UMOSFET) with semi-super-junction shielded structure (SS-UMOS) is proposed and compared with conventional trench MOSFET (CT-UMOS) in this work. The advantage of the proposed structure is given by comprehensive study of the mechanism of the local semi-super-junction structure at the bottom of the trench MOSFET. In particular, the influence of the bias condition of the p-pillar at the bottom of the trench on the static and dynamic performances of the device is compared and revealed. The on-resistance of SS-UMOS with grounded (G) and ungrounded (NG) p-pillar is reduced by 52% (G) and 71% (NG) compared to CT-UMOS, respectively. Additionally, gate oxide in the GSS-UMOS is fully protected by the p-shield layer as well as semi-super-junction structure under the trench and p-base regions. Thus, a reduced electric-field of 2 MV/cm can be achieved at the corner of the p-shield layer. However, the quasi-intrinsic protective layer cannot be formed in NGSS-UMOS due to the charge storage effect in the floating p-pillar, resulting in a large electric field of 2.7 MV/cm at the gate oxide layer. Moreover, the total switching loss of GSS-UMOS is 1.95 mJ/cm2 and is reduced by 18% compared with CT-UMOS. On the contrary, the NGSS-UMOS has the slowest overall switching speed due to the weakened shielding effect of the p-pillar and the largest gate-to-drain capacitance among the three. The proposed GSS-UMOS plays an important role in high-voltage and high-frequency applications, and will provide a valuable idea for device design and circuit applications.

Interaction is the main feature of social media, while in recent years, frequent privacy disclosure events of the social media user affect users’ privacy disclosure behavior. In this paper, we explore the mechanism of interaction characteristics by social media apps on users’ privacy disclosure behavior. Using SOR theoretical models and the privacy calculus theory, the effects of privacy disclosures on TikTok are examined. Structural equation modeling is used to analyze the data from 326 questionnaires. We concluded that human–computer interaction (perceived personalization, perceived control) and interpersonal interaction (perceived similarity) positively and negatively affected perceived benefits and perceived risks, respectively, and had positive effects on intention to disclose privacy through perceived benefits and perceived risks, respectively, except that perceived personalization had no effect on perceived risk and intention to disclose privacy. In addition, perceived benefits and perceived risks played an intermediary role in interactivity and privacy disclosure intention. Finally, we provided countermeasures and suggestions for social media operators and policy makers.

The coronary slow flow phenomenon (CSFP) is a poorly recognized clinical entity characterized by delayed distal vessel opacification in the absence of epicardial coronary stenosis and presently lack of specific data on the clinical profile and outcome. We investigated a cohort of 429 patients who fulfilled the criteria for CSFP to explore the clinical feature, outcome, and risk factor of prognosis. Two teams (clinical center and core lab) were blind to patient data for the assessment of coronary angiograph using corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC). The study cohort consisted of 429 patients (294 men, 68.5%), aged from 30 to 78 years (mean, 54 years). Two hundred patients (46.6%) out of 429 patients had a history of hypertension, 72 (16.8%) had diabetes mellitus, and 222 (51.7%) had dyslipidemia. All the rates of agreement between two teams in evaluating whether normal flow (CTFC ≤ 27 frames) or slow flow (CTFC > 27 frames) were moderate (0.40 κ 50 years (hazard ratio (HR) = 2.2, 95% CI: 1.0 to 4.9, and P=0.042), hypertension (HR = 2.1, 95% CI: 1.1 to 4.2, and P=0.021), and dyslipidemia (HR = 2.0, 95% CI: 1.0 to 3.9, and P=0.042). CSFP affects predominantly patients at middle age and above but can occur in any age group; CSFP should be more concerned, particularly in patients >50 years old with hypertension and dyslipidemia.

BACKGROUND The aim of this study was to investigate the significance of folate receptor-mediated staining solution (FRD) in examination of cervical lesions during gynecological examination. MATERIAL AND METHODS A total of 404 patients participated in this study. FRD staining was applied to screen high grade cervical lesions. ThinPrep cytology test (TCT) and human papillomavirus (HPV) testing were also used for screening high grade cervical lesions. Coincidence rate and KAPPA value of different methods were compared by SPSS software. RESULTS As for CIN2+ and CIN3+, sensitivities for HPV testing were (96.92% and 97.78%) >TCT classification 1 (90.77% and 91.11%) >FRD staining (80.00% and 86.67%) >TCT classification 2 (70.77% and 77.78%), respectively. While specificities for HPV testing were (7.08% and 6.44%)

The oxidation states of polymers and their stabilities are of great importance for their application in energy storage systems. In this paper, we report an air-stable triphenylamine–triazine-based conjugated microporous polymer (pTTPATA) with the smart function of changing color by simply changing the applied voltage. Uniquely, the yellow colored neutral polymer switches to a red color upon oxidation (p-doping) and the red color remains stable even for ten hours after removal of the applied potential, which allows an in-depth analysis of the pTTPATA in the oxidized state. X-ray photoelectron spectroscopy (XPS) confirms that large amounts of radical cations from the triazine groups as well as a small proportion of those from oxidized triphenylamine are present in the stable red-colored oxidized state of the pTTPATA film. Electrochemistry and density functional theory (DFT) calculations demonstrate that only the triphenylamine group is oxidized in the pTTPATA polymer under the applied voltages. Thus, we conclude that most of the oxidation of the pTTPATA polymer occurs from the structural resonance from the oxidation of the triphenylamine group to the relatively more stable radical cation of the triazine group, which results in a stable red colored oxidation state. More importantly, the structural resonance in the special oxidation state induces the charge storage of triazine except the charge storage of triphenylamine, which results in a high specific capacity of ∼81 mA h g−1, among the best reported values for conducting polymers-based energy storage systems. The combination of these fascinating properties results in an intelligent energy storage device that changes its color based on its charged state so that the state of charge can be monitored by simple visual inspection.

Objective To investigate the long-term clinical outcomes of patients with adenomyosis treated by high-intensity focused ultrasound (HIFU). Materials and methods From June 2012 to January 2020, 2311 patients with adenomyosis were treated with HIFU at our center, 1982 patients who have complete clinical data were retrospectively reviewed. Among the patients who completed the follow-up, 485 were treated with HIFU alone, 289 were treated with HIFU followed by GnRH-a, 255 were treated with HIFU combined with Mirena and 594 were treated with HIFU combined with GnRH-a and Mirena. The dysmenorrhea severity pain score and average menorrhagia severity score before and at 3 months, 6 months, 1 year, 2 years, 3 years and 5 years after HIFU were compared. The adverse effects were recorded. In addition, the efficacy between patients treated with GnRH-a and/or Mirena were compared. Results After HIFU ablation, the dysmenorrhea severity pain score and the menorrhagia severity score were significantly decreased at each follow-up time point. However, it was observed that as the follow-up time increased, the effective rate of HIFU treatment in improving dysmenorrhea and menorrhagia decreased. The 6 months and 3 years follow-up results showed that the efficacy of HIFU combined with Mirena and HIFU combined with GnRH-a and Mirena were significantly higher than HIFU alone and HIFU combined with GnRH-a (p

Selective ablation of endometriotic lesions in the myometrium reduces the extent and sizes of adenomyosis lesions and limits the ectopic endometrial functions and growth. Eventually, it may achieve the purpose of improving symptoms.

Fuzzing has been a great success in discovering real-world complex programs vulnerabilities. However, fuzzing achieves this effect by blindly generating a large number of test cases, which undoubtedly contains a lot of meaningless mutation inputs. To solve the blindness, machine learning technology is applied to fuzzing in recent work. Some of the machine learning based methods focus on locating and mutating the key bytes in the input, but they do not pay attention to the characteristics in the field of fuzzing when they combine machine learning technology with fuzzing. In this paper, we implement a new fuzzer, called Speed-Neuzz, which uses neural networks to model the branch behaviours of the program based on accurate training data after mitigating the hash collision of AFL. Furthermore, SpeedNeuzz locates and mutates critical bytes in the program input with a gradient-based strategy as well as neighbor edge information. Taking the neighbor edge knowledge into account, we can further reduce the blindness of the mutation based on gradient information so that SpeedNeuzz can generate a large number of quality inputs. Experiments on several real-world programs prove that SpeedNeuzz can achieve higher edge coverage than the state-of-the-art fuzzer NEUZZ under the same time budget.

Estimation of the Weibull parameters is vital to reliability engineering. In engineering, the least squares regression of y (LS Y) is often used for Weibull distribution’s parameter estimation. LS Y only involves the error of the y coordinate but doesn’t involve the error of the x coordinate. Similarly, the least squares regression of x (LS X) only involves the error of x coordinate but doesn’t involve the error of y coordinate. Total least squares (TLS), however, involves both the error of x coordinate and y coordinate, therefore, TLS is introduced to estimate the parameters of the Weibull distribution in this paper. The comparison and selection among the estimators of the three parameter estimation methods is carried out using Monte Carlo simulations. The results demonstrate that we can directly choose LS X, when sample size n > 20. It is necessary to select the parameter estimation methods by comparing \( Q_{T} \) in TLS constrained criterion and \( Q_{x} \) in LS X constrained criterion, when sample size n < 20.

Coronary artery aneurysms (CAAs) are infrequent but not rare. Because of the lack of supportive data and a substantial knowledge gap in this field, clinicians are in a dilemma how to manage patients with coronary artery aneurysms. Most often, CAAs are discovered incidentally, while symptomatic patients present with diverse complications of unstable angina, myocardial infarction, arrhythmias, or sudden cardiac death. Therapeutical approaches consist of surgical procedure, percutaneous coronary intervention (PCI), and medical management. Because of the scarcity of randomized trials or large-scale data on symptomatic and asymptomatic patients with coronary artery aneurysms, the management of these patients poses considerable challenges for the cardiologists. This review summarizes the current literature, a proposed algorithm for the management of CAAs is highlighted in the text. In view of the majority of current proposal information based on small series of case reports or observational studies, an individualized therapeutic regimen should be on the basis of the location, expansion by time, morphology, complications, and etiologies of the coronary artery aneurysms, the clinical presentations, and the patient's characteristics.

In order to improve the precision and maintain the precision’s stability of the motorized spindle, it’s of great significance to research the production regularity of thermal error of the motorized spindle. Therefore, the thermal behaviour of spindle were studied by thermal-structural coupled numerical simulation in this paper. Based on the thermoelasticity, the relative thermal displacement model of the inner and outer ring’s radial direction for angular contact ball bearing can be built. And then the total radial displacement of spindle were studied. In order to verify the effectiveness of the proposed methods, the experiment was carried out. The contrastive analysis between the analysis results and test results of motorized spindle error is made. The analysis results show that this method has good accuracy in predicting the temperature and thermal error of motorized spindle.

In mathematical physics, the space-fractional diffusion equations are of particular interest in the studies of physical phenomena modelled by Levy processes, which are sometimes called super-diffusion equations. In this article, we develop the differential quadrature (DQ) methods for solving the 2D space-fractional diffusion equations on irregular domains. The methods in presence reduce the original equation into a set of ordinary differential equations (ODEs) by introducing valid DQ formulations to fractional directional derivatives based on the functional values at scattered nodal points on problem domain. The required weighted coefficients are calculated by using radial basis functions (RBFs) as trial functions, and the resultant ODEs are discretized by the Crank-Nicolson scheme. The main advantages of our methods lie in their flexibility and applicability to arbitrary domains. A series of illustrated examples are finally provided to support these points.

Selective laser melting (SLM) is a form of additive manufacturing technology that makes it possible to create complex parts directly from metal powders. This technology offers a good balance betwee...

Background To improve the poor prognosis of congestive heart failure (CHF), early and accurate diagnosis is necessary. Relaxin is an endogenous cardiovascular peptide, and its plasma level is usually increased in patients with CHF. In this pilot study, we aimed to determine the diagnostic value of relaxin and B-type natriuretic peptide (BNP) in patients with and without CHF. Materials and Methods The plasma level of relaxin was measured by enzyme-linked immunosorbent assay and plasma level of BNP by fluorescence immunoassay. The area under the receiver operating characteristic curve was used to assess the diagnostic value of relaxin and BNP. Results We included 81 patients with decompenstated CHF and 36 controls. Plasma levels of relaxin and BNP were both higher in CHF patients than in controls. The correlation between plasma levels of relaxin and BNP and between relaxin or BNP and cardiac function was nonlinear. Relaxin had medium diagnostic value, and BNP had higher value for cardiac function and CHF. At a cutoff of 39.76 pg/mL relaxin, sensitivity was 82.7%, specificity 55.6%, sum of the highest positive predictive value 80.5% and negative predictive value 58.8%. Although the diagnostic value was not better for relaxin than BNP, their combined assessment improved the sensitivity and specificity of diagnosis for CHF as compared with BNP alone. Conclusions Combined assessment of relaxin and BNP may improve the diagnosis of decompensated CHF, which may have potential application in the clinic.

In quantum physics, fractional Schrodinger equation is of particular interest in the research of particles on stochastic fields modeled by the Levy processes, which was derived by extending the Feynman path integral over the Brownian paths to a path integral over the trajectories of Levy fights. In this work, a fully discrete finite element method (FEM) is developed for the Riesz space-fractional coupled nonlinear Schrodinger equations (CNLS), conjectured with a linearized Crank–Nicolson discretization. The error estimate and mass conservative property are discussed. It is showed that the proposed method is decoupled and convergent with optimal orders in $L^{2}$ -sense. Numerical examples are performed to support our theoretical results.

In this work, the triphenylamine derivatives with the different electron donating/with-drawing groups, such as 4-(diphenylamino)benzonitrile (TPA-CN), 4-methyltriphenylamine (TPA-CH 3 ) and 4-methoxytriphenylamine (TPA-OCH 3 ) were successfully synthesized, and the corresponding polymers were then prepared by chemical oxidative polymerization. The chemical structure, morphology and charge-discharge performance of the prepared polymers as the cathodes were characterized by fourier transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV-vis), scanning electron microscopy (SEM), cycling voltammograms (CV) and galvanostatic charge-diacharge testing, respectively. The results showed that the different electronic effect groups affected obviously the redox potential of polytriphenylamine, in which the electron with-drawing group improved the potential plateaus of the polytriphenylamine, while the electron donating groups generally led to the opposite results. And specially, the introduction of CN group as the electron with-drawing group into polytriphenyamine obviously improved the potential plateaus of the lithium ion battery from 3.6 V of PTPAn to 3.8 V of PTPA-CN. The explored work would provide a valuable reference for preparing the organic cathode materials with the high redox potential by the molecular design method.

The aim of this study was to retrospectively analyse the clinical data of 122 patients with caesarean scar pregnancy (CSP) treated in our hospital, to compare the outcomes between high-intensity focused ultrasound (HIFU) and uterine artery embolisation (UAE).Among the 122 patients, 76 patients were treated with HIFU followed by suction curettage under hysteroscopic guidance, 46 patients were treated with UAE followed by suction curettage under hysteroscopic guidance. Pain score, intraoperative blood loss in suction curettage under hysteroscopy guidance, time for vaginal bleeding, β-human chorionic gonadotropin (β-hCG) to return to normal level, normal menstruation recovery, hospital stay, and the adverse effects were all compared.No statistically significant differences between the two groups in the intraoperative blood loss, hospital stay, time for β-human chorionic gonadotropin (β-hCG) to return to normal level, or time for normal menstruation recovery were observed. The pain score was lower and the adverse effects were fewer in the HIFU group than those in the UAE group. However, the time for vaginal bleeding was longer in the patients treated with HIFU than that of patients treated with UAE.Based on our results, it appears that either HIFU or UAE combined with suction curettage under hysteroscopic guidance is safe and effective in treating patients with CSP. Compared with UAE, HIFU treatment for CSP has the advantages of a lower pain score and fewer adverse effects.

In this paper, we consider a fully discrete finite element method FEM to solve the two-dimensional nonlinear Fisher' equation with Riesz fractional derivatives in space. This method is chiefly performed by using Crank–Nicolson discretization in conjunction with a linearized approach in time and FEM in space. The existence, uniqueness of the weak solution, and the numerical stability of the scheme are proved in great detail. The optimal error estimate computed by -norm showed both in time and space is derived by introducing a fractional orthogonal projection. Moreover, several numerical examples are conducted on unstructured triangular meshes by a properly designed algorithm.

Coverage-guided fuzzing is one of the most effective solutions for vulnerability discovery. Among coverage-guided fuzzing, full-speed fuzzing, such as UnTracer, traces test cases only when they discover new coverage. Due to the high expense of tracing test cases, full-speed fuzzers improve the efficiency of fuzzing by tracing only coverage-increasing test cases. However, the existing full-speed fuzzer (i.e., UnTracer) is based on basic block coverage, suffering a severe problem called edge collision. Moreover, such fuzzers neglect the path frequency, which affects fuzzing effectiveness. In this paper, we propose CSI-Fuzz, a fuzzer utilizing coverage sensitive instrumentation to address the problems of existing full-speed fuzzing. CSI-Fuzz directly instruments at edges, which solves the problem of edge collision. Meanwhile, CSI-Fuzz sets path identifiers to count the frequency of covered paths. Our CSI-Fuzz can be recognized as an add-on and seamlessly applied to existing coverage-guided fuzzers. We accordingly implement CSI-Fuzz based on two widely-adopted fuzzers, AFL and AFLFast, to evaluate its performance. The experiments demonstrate that CSI-Fuzz discovers more edges than AFL, AFLFast, and UnTracer. Additionally, CSI-Fuzz exposes more bugs than the other fuzzers.

This paper conduct research to the temperature field distribution and spindle’s thermal deformation of motorized spindle by applying finite element thermal-structural coupled numerical simulation technology. And this paper also researched the radial displacement produced by the inner and outer ring’s axial displacement of the angular contact ball bearing. Thus the combination between the finite element thermal-structural coupled numerical simulation technology and thermal error analytic modelling is realized. The analysis results of motorized spindle error is made. The analysis results show that this method is effective in predicting the temperature and thermal error of motorized spindle.