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With the application of digital information technology and communication technology, industrial intelligence and integration also began to develop rapidly, and the importance of the research on bus communication in industrial control communication also increased. As the first international bus standard, PROFIBUS has been widely used in the field of industrial control; in recent years, it was mainly used to connect devices to the control layer and convert data through token transmission. Based on the understanding of the transmission mechanism of PROFIBUS fieldbus protocol, this article carries out a simulation study on its communication performance. Through analysis of the data link layer, changing the target token cycle time (high and low priority) and random setting each site message number, as well as the number of master station and slave station, how the main token latency and packet loss rate and efficiency of bus affect the change of performance parameters was observed. For multiple communication systems, the relationship between the address value on the main token ring and transport performance is found by experiments on the site address value on the main token ring and the target token cycle time value. Finally, the scheduling algorithm is applied to the communication scheduling of PROFIBUS fieldbus. The results confirm that the scheduling algorithm has better transmission efficiency than the traditional MAC media access protocol under the condition that the load rate does not exceed 100%, which makes up for the shortcomings of the original PROFIBUS bus system and makes the communication performance better. [ABSTRACT FROM AUTHOR]

Rotational motions are generally enabled by the flow energy for generating electricity or by the electric energy to drive various mechanical motions. Here, we report a fundamentally different approach (which we name "semi-flexible rotor") that uses omnipresent ultralow-frequency (<5 Hz) vibrations as the energy source to achieve high-speed rotational motions. The semi-flexible rotor comprises mainly a turntable, an elastic support, a lid, and a piece of rope, in which the periodically tensioned and released rope under external excitations provides the torque for spinning the turntable. The feasibility of the proposed approach is confirmed by both experimental measurements and theoretical simulations. As excited by a quasi-harmonic vibration with an amplitude of 10 mm, the rotor achieves a high rotational speed of up to 250 rad/s (2400 rpm) at around 2 Hz, and can provide an average rotational speed higher than 50 rad/s within a frequency range from 0.5 Hz to 5 Hz. The semi-flexible rotor is thus an option for realizing some rotation-based devices (e.g., miniature centrifuges) that work in scenarios without electricity supply or for designing efficient energy harvesters that exploit ubiquitous ultralow-frequency vibrations to generate electricity. [ABSTRACT FROM AUTHOR]

With the application of digital information technology and communication technology, industrial intelligence and integration also began to develop rapidly, and the importance of the research on bus communication in industrial control communication also increased. As the first international bus standard, PROFIBUS has been widely used in the field of industrial control; in recent years, it was mainly used to connect devices to the control layer and convert data through token transmission. Based on the understanding of the transmission mechanism of PROFIBUS fieldbus protocol, this article carries out a simulation study on its communication performance. Through analysis of the data link layer, changing the target token cycle time (high and low priority) and random setting each site message number, as well as the number of master station and slave station, how the main token latency and packet loss rate and efficiency of bus affect the change of performance parameters was observed. For multiple communication systems, the relationship between the address value on the main token ring and transport performance is found by experiments on the site address value on the main token ring and the target token cycle time value. Finally, the scheduling algorithm is applied to the communication scheduling of PROFIBUS fieldbus. The results confirm that the scheduling algorithm has better transmission efficiency than the traditional MAC media access protocol under the condition that the load rate does not exceed 100%, which makes up for the shortcomings of the original PROFIBUS bus system and makes the communication performance better. [ABSTRACT FROM AUTHOR]

Summary: The efficient exploitation of ubiquitous low‐frequency mechanical excitations through electromagnetic induction is important for implementing self‐sustained low‐power electronics. Conventional electromagnetic energy harvesters (EMEHs) have been usually designed as a 1‐degree‐of‐freedom (1‐DOF) linear system with a high resonant frequency, resulting in poor performance under low‐frequency excitations. To solve this key issue, this paper presents four 2‐DOF cylindrical EMEHs with various configurations. Theoretical models for the four EMEHs are built and then validated by experiment. With the theoretical models, a parametric study is carried out to reveal the energy harvesting performance of the four 2‐DOF EMEHs. The results indicate that supporting a 1‐DOF EMEH within a large tube using springs or magnetic coupling to construct a 2‐DOF EMEH can lower the operating frequency, endowing the 2‐DOF EMEH with improved performance under low‐frequency excitations. Moreover, the 2‐DOF EMEH can always provide higher power outputs than the corresponding 1‐DOF EMEH except the linear 2‐DOF EMEH configuration with overly stiff inner springs. Furthermore, for the nonlinear 2‐DOF EMEH, the output power can be optimized by adjusting the spring stiffness and the length of the inner tube. In addition, increasing the mass of the inner center magnet can enhance the power output and in the meanwhile make the operational frequency shift toward the left (lower frequency). [ABSTRACT FROM AUTHOR]

The research work in this paper belongs to the application of granular computing, graph theory and its application in fault detection and diagnosis. It is a cross cutting and frontier research field in computer science, information science and graph theory. The results of this paper are of great significance to the application of the fault detection and diagnosis of the ocean boilers system. This research combines granular computing theory and signed directed graph, and proposes a new method of fault diagnosis, and applies it to the fault diagnosis of ocean ship boiler system. [ABSTRACT FROM AUTHOR]

In this paper, the issue of improving control performance of a network-based control system in a different perspective from control algorithms was fully addressed. Some important performance-affecting elements including design of network architecture, configuration, and delay compensation were investigated and some methods presented. The presented design and implementation of a network-based cascade control system with a real laboratory pilot plant involved adopting two different control approaches based on Foundation Fieldbus and Ethernet, respectively. We presented some practically feasible approaches to improve control performance of the system, including improved function block configuration scheme, synchronization control methodology based on IEC61499, output estimation algorithm based on neural network, and methods for reducing network transmission by improving hardware and network architecture. Control effects under the proposed methodologies were also given. Experimental and on-site practice validated these methodologies. [ABSTRACT FROM AUTHOR]

Building resilient supply chain is an effective way to deal with uncertain risks. First, by analyzing the self-organization of supply chain, the supply chain resilience is described as a macroscopic property that generates from self-organizing behavior of each enterprise on the microlevel. Second, a MAS-based supply chain resilience model is established and its local fitness function, neighborhood structure, and interaction rules that are applicable to supply chain system are designed through viewing the enterprise as an agent. Finally, with the help of a case, we find that there is an agglomeration effect and a SOC characteristic in supply chain and the evolution of supply chain is controlled by parameters of MAS. Managers can control the supply chain within the resilient range and choose a good balance between interest and risk by controlling enterprises' behavior. [ABSTRACT FROM AUTHOR]

Abstract: Active disturbance rejection control (ADRC) is an effective control method to improve dynamic performance of control system based on disturbance estimation and compensation. In this paper, a practically effective method for tuning of ADRC parameters was proposed since tuning of ADRC parameters is one of the most important parts in its application to process control. A set of reusable initial values for ADRC parameters was decided with ESO stability analysis and experimental approaches. Effect of ADRC parameters on control performance was also investigated and detailed description of tuning method for ADRC parameters in closed-loop control was proposed. The parameter tuning procedure for ADRC can be started with these initial values and the tuning is carried out based on the effect of ADRC parameters on control performance. ADRC was applied to the control of superheated steam temperature in large-capacity generation units as ADRC-PID cascade control. Parameter tuning for the ADRC-PID was described. Simulation results of ADRC-PID, traditional PID-PID and DMC-PID cascade control were presented and compared. The detailed implementation of the designed system based on Distributed Control System (DCS) was given as well. The results of real-time simulation based on DCS proved the effectiveness of the proposed strategy. [Copyright &y& Elsevier]

An effective way to deal with high-risk and low-probability disruptions is to create a resilient cluster supply chain, in which the study of resilience lies in its recovery mechanism when failures occur. First, the paper describes the representation method of cluster supply chain resilience. Second, a cluster supply chain network structure generation model is proposed. And based on cascading effect model, it makes analysis of dynamic evolution process when cluster supply chain failure happens. Then it focuses on the self-organization characteristic, which contributes to cluster supply chain emergence overall resilient recovery through local self-organization reconstruction behavior. We also make theoretical analysis of cluster supply chain network characteristics and its effect on the resilience, which helps to illustrate that the root of vulnerability lies in cascading failure while self-organization is the key to resilient recovery. Besides, with the study of self-organization characteristic, it provides theoretical guidance for local control and further achievement of overall resilient optimization. [ABSTRACT FROM AUTHOR]

Plant microbiota (the microorganisms that live in any associations with plant tissues) represents a rather unexplored area of metagenomic research compared with soils and oceans. Constructing a metagenomic library for plant microbiota is technically challenging. Using all the biomass without pre-enrichment could lead to vast proportions of the host plant DNA in the metagenomic library, doubtless obliterating the microbial contribution. Therefore, the first and essential step is to enrich for the constituent microorganisms from plant tissues. Here, a strong enrichment for plant microbiota was achieved by coupling SDS (sodium dodecyl sulfate) with NaCl, creating a predominantly microbial metagenomic library that contains 88% bacterial inserts. 16S rDNA sequence analysis revealed that the metagenomic DNA of enrichments originates from very diverse microorganisms. At least 74 distinct ribotypes (at a 97% threshold) from seven different bacterial phyla were identified and mainly distributed among Actinobacteria and Proteobacteria. Additionally, a simplified version of Amplified Ribosomal DNA Restriction Analysis (ARDRA) was developed for a quick and efficient assessment of the enriching procedures. This work opens further insight into the great biotechnical potential of plant microbiota, holding more potential for drug discovery through a metagenomic strategy, and paving the way for recovery and biochemical characterization of functional gene repertoire from plant microbiota. [ABSTRACT FROM AUTHOR]

A wideband bandpass filter constructed into folded substrate-integrated waveguide (FSIW) is proposed, incorporating with the stripline compact resonant cell (CRC). The folded SIW preserves nearly the same propagation characteristics with its counterpart substrate-integrated waveguide (SIW); however, the width of FSIW is only half of SIW, providing a more compact platform for many novel circuits or subsystems. A prototype of this wideband bandpass filter was fabricated and measured. Good agreements are observed between the experimental results and the simulations. The results demonstrate a wide passband about 83.7% (from 3.3 to 8.05 GHz) at -10 dB return loss and the insertion loss in the entire passband is less than 0.26 dB. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 390–393, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23117 [ABSTRACT FROM AUTHOR]

The novel folded substrate-integrated waveguide (FSIW) is 50% narrower than the substrate-integrated waveguide, but both have similar propagation characteristics. This paper derives the analytical formulas of propagation and cutoff characteristics of the FSIW, as well as the formulas to calculate the width and gap of the central metal septum. Very good agreements (<2% error) are observed among the results of the theoretical formulas, numerical simulations, and hardware experiments over wide frequency and parameter ranges. [ABSTRACT FROM AUTHOR]

The H-plane folded substrate integrated waveguide (FSIW) bend with circular right-angle in C band and X band are investigated in this article. The design formulas of the folded substrate integrated waveguide are proposed first, followed by the proper design principles of FSIW bends. Comparisons between FSIW bends and SIW bends have been made to demonstrate the validity of the design formulas. In addition, the propagation characteristics between FSIW sections and FSIW bends have been compared also, almost same propagation characteristics can be observed within. However, some fluctuations can be seen from the insertion losses of FSIW bends, implying the occurrence of the higher modes. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2977–2981, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22953 [ABSTRACT FROM AUTHOR]

Debris flow risk comprehensively reflects the natural and social properties of debris flow disasters and is composed of the risk of the disaster-causing body and the vulnerability of the carrier. The Bailong River Basin (BRB) is a typical mountainous environment where regional debris flow disasters occur frequently, seriously threatening the lives of residents, infrastructure, and regional ecological security. However, there are few studies on the risk assessment of mountainous debris flow disasters in the BRB. By considering a complete catchment, based on remote sensing and GIS methods, we selected 17 influencing factors, such as area, average slope, lithology, NPP, average annual precipitation, landslide density, river density, fault density, etc. and applied a machine learning algorithm to establish a hazard assessment model. The analysis shows that the Extra Trees model is the most effective for debris flow hazard assessments, with an accuracy rate of 88%. Based on socio-economic data and debris flow disaster survey data, we established a vulnerability assessment model by applying the Contributing Weight Superposition method. We used the product of debris flow hazard and vulnerability to construct a debris flow risk assessment model. The catchments at a very high-risk were distributed mainly in the urban area of Wudu District and the northern part of Tanchang County, that is, areas with relatively dense economic activities and a high disaster frequency. These findings indicate that the assessment results provide scientific support for planning measures to prevent or reduce debris flow hazards. The proposed assessment methods can also be used to provide relevant guidance for a regional risk assessment of debris flows in the BRB and other regions. [ABSTRACT FROM AUTHOR]

Side-channel analysis (SCA) is a powerful technique to reveal the secrets using detectable physical leakages from logic elements, which brings severe security threats to modern circuits. To alleviate this problem, applying cell-level countermeasure is usually a suitable solution, which is mainly implemented as dual-rail precharge logic. Mace et al. has the proposed dynamic current mode logic (DyCML) scheme as a novel technology to resist SCA, whose power consumption is constant regardless of the data processed. However, the DyCML-based sequential elements are still in blank field. So, we have implemented a novel flip-flop compatible with DyCML, whose enhanced security has been proved by corresponding simulations. [ABSTRACT FROM AUTHOR]

Purpose: To develop and evaluate the performance of radiomics-based computed tomography (CT) combined with machine learning algorithms in detecting occult vertebral fractures (OVFs). Materials and methods: 128 vertebrae including 64 with OVF confirmed by magnetic resonance imaging and 64 corresponding control vertebrae from 57 patients who underwent chest/abdominal CT scans, were included. The CT radiomics features on mid-axial and mid-sagittal plane of each vertebra were extracted. The fractured and normal vertebrae were randomly divided into training set and validation set at a ratio of 8:2. Pearson correlation analyses and least absolute shrinkage and selection operator were used for selecting sagittal and axial features, respectively. Three machine-learning algorithms were used to construct the radiomics models based on the residual features. Receiver operating characteristic (ROC) analysis was used to verify the performance of model. Results: For mid-axial CT imaging, 6 radiomics parameters were obtained and used for building the models. The logistic regression (LR) algorithm showed the best performance with area under the ROC curves (AUC) of training and validation sets of 0.682 and 0.775. For mid-sagittal CT imaging, 5 parameters were selected, and LR algorithms showed the best performance with AUC of training and validation sets of 0.832 and 0.882. The LR model based on sagittal CT yielded the best performance, with an accuracy of 0.846, sensitivity of 0.846, and specificity of 0.846. Conclusion: Machine learning based on CT radiomics features allows for the detection of OVFs, especially the LR model based on the radiomics of sagittal imaging, which indicates it is promising to further combine with deep learning to achieve automatic recognition of OVFs to reduce the associated secondary injury. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes mellitus is a metabolic disease that affects multiple target organs. Current data on right ventricular damage in type 2 diabetes, especially in prediabetes, are limited. Due to the anatomical characteristics of the right ventricle, the assessment of the right ventricle by conventional echocardiography is difficult, whereas the ultrasound two‐dimensional speckle tracking echocardiography can provide information on myocardial systolic function by tracking the motion information of myocardial speckles, which can sensitively reflect myocardial mechanical changes. Aims: To assess the effect of prediabetes and diabetes with preserved left ventricular ejection fraction on right ventricular myocardial systolic function and to identify independent risk factors affecting right ventricular systolic function. Methods: A total of 49 normoglycaemic (NG) healthy individuals, 43 prediabetics (PDM), and 52 type 2 diabetics (T2DM) were recruited. All study subjects underwent conventional echocardiography and two‐dimensional speckle tracking echocardiography (2D‐STE). Results: The right ventricular global longitudinal strain (RVGLS) (20.80 ± 1.96% vs. 18.99 ± 3.20% vs. 16.85 ± 4.01%), left ventricular global longitudinal strain (LVGLS), and interventricular septal longitudinal strain (IVS‐LS) (17.28 ± 2. 35% vs. 16.14 ± 3.22% vs. 15.53 ± 3.33%) gradually decreased from the controls, through patients with prediabetes, to those with diabetes (p <.001). Right ventricular free wall strain (RVFW‐LS) was higher in the control group (25.63 ± 4.58% vs. 22.83 ± 4.83% vs. 20.79 ± 4.92%) than in the other two groups with a statistically significant difference (p <.001), while RVFW‐LS was not statistically different between the prediabetic and diabetic groups. Multivariate regression analysis showed that HbA1c (β = −.626, p <.001), IVS‐LS (β =.417, p <.001), and left ventricular end‐diastolic diameter (LVEDd) (β =.191, p =.011) were independently correlated with RVGLS. Conclusions: Two‐dimensional speckle tracking echocardiography can sensitively detect subtle changes in the early impairment of right ventricular systolic function in patients with abnormal glucose metabolism. Type 2 diabetes is the common mechanism causing impaired myocardial mechanics in the right and left ventricles. The reduced global systolic longitudinal strain of the right ventricle was associated with reduced global septal longitudinal strain and left ventricular remodeling. HbA1c is an independent predictor of the global longitudinal strain of the right ventricle, and controlling blood glucose levels may be expected to improve the extent of myocardial damage. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to restore orbicularis oculi muscle function using the implantable artificial facial nerve system (IAFNS). The in vivo part of the IAFNS was implanted into 12 rabbits that were facially paralyzed on the right side of the face to restore the function of the orbicularis oculi muscle, which was indicated by closure of the paralyzed eye when the contralateral side was closed. Wireless communication links were established between the in vivo part (the processing chip and microelectrode) and the external part (System Controller program) of the system, which were used to set the working parameters and indicate the working state of the processing chip and microelectrode implanted in the body. A disturbance field strength test of the IAFNS processing chip was performed in a magnetic field dark room to test its electromagnetic radiation safety. Test distances investigated were 0, 1, 3 and 10 m, and levels of radiation intensity were evaluated in the horizontal and vertical planes. Anti-interference experiments were performed to test the stability of the processing chip under the interference of electromagnetic radiation. The fully implanted IAFNS was run for 5 h per day for 30 consecutive days to evaluate the accuracy and precision as well as the long-term stability and effectiveness of wireless communication. The stimulus intensity (range, 0-8 mA) was set every 3 days to confirm the minimum stimulation intensity which could indicate the movement of the paralyzed side was set. Effective stimulation rate was also tested by comparing the number of eye-close movements on both sides. The results of the present study indicated that the IAFNS could rebuild the reflex arc, inducing the experimental rabbits to close the eye of the paralyzed side. The System Controller program was able to reflect the in vivo part of the artificial facial nerve system in real-time and adjust the working pattern, stimulation intensity and frequency, range of wave and stimulation time. No significant differences in the stimulus intensities were observed during 30 days. The artificial facial nerve system chip operation stable in the anti-interference test, and the radiation field strength of the system was in a safe range according to the national standard. The IAFNS functioned without any interference and was able to restore functionality to facially paralyzed rabbits over the course of 30 days. [ABSTRACT FROM AUTHOR]

Leiomyosarcomas (LMS) are mesenchymal neoplasms that arise from smooth muscle cells, which less frequently occur in veins. Commonly, leiomyosarcoma accompanied with necrosis and cystic degeneration, which noted as non-enhanced areas on radiological examinations were seen frequently in the literature. We present a rare case of a leiomyosarcoma arising from the inferior vena cava, invading into the right atrium, found accidentally in a 46-year-old male who clinically manifested as progressive dyspnea on exertion. Radiological examinations showed a moderate heterogeneous enhancement tumor followed with foci of non-enhancement area in the central, which was not definitely in line with the pathological findings. The imaging features and differential diagnosis of the tumor are outlined here. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effect of the mammalian target of rapamycin (mTOR) signaling pathway on thoracic aortic aneurysm (TAA) development. The study used a calcium chloride (CaCl2)-induced rat TAA model to explore the potential role of mTOR signaling pathway in the disease development. Adult male Sprague-Dawley rats underwent the periarterial exposure of thoracic aorta to either 0.5 M CaCl2 or normal saline, and a subgroup of CaCl2-treated rats received rapamycin 1 day prior to surgery. Without pre-administering rapamycin, significantly enhanced phosphorylation of mTOR and expression of proinflammatory cytokines [i.e., tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and interleukin (IL)-1β] were observed in the CaCl2-treated aortic segments 2 days post-treatment compared with the NaCl-treated segments. At 2 weeks post-treatment, hematoxylin and eosin and Verhoeff-Van Gieson staining revealed aneurysmal alteration and disappearance of normal wavy elastic structures in the aortic segments exposed to CaCl2. In contrast, the CaCl2-induced TAA formation was inhibited by pre-administering rapamycin to CaCl2-treated rats, which demonstrated attenuated mTOR phosphorylation and downregulation of the proinflammatory mediators (i.e., TNF-α, IL-6, IL-1β, matrix metallopeptidases 2 and 9) to the control level. Further in vitro cell culture experiments using aortic smooth muscle cell (SMC) suggested that the inhibition of the mTOR signaling pathway by rapamycin could promote the differentiation of SMCs, as reflected by the reduced expression of S100A4 and osteopontin. The present study indicated that the early enhanced mTOR signaling pathway in the TAA development and mTOR inhibitor rapamycin may inhibit CaCl2-induced TAA formation. [ABSTRACT FROM AUTHOR]

Dengue as an acute infectious disease threatens global public health and has sparked broad research interest. However, existing studies generally ignore the spatial dependencies involved in dengue forecast, and consideration of temporal periodicity is absent. In this work, we propose a spatiotemporal component fusion model (STCFM) to solve the dengue risk forecast issue. Considering that mosquitoes are an important vector of dengue transmission, we introduce feature factors involving mosquito abundance and spatiotemporal lags to model temporal trends and spatial distributions separately on the basis of statistical properties. Specifically, we conduct multiscale modeling of temporal dependencies to enhance the forecast capability of relevant periods by capturing the historical variation patterns of the data across different segments in the temporal dimension. In the spatial dimension, we quantify the multivariate spatial correlation analysis as additional features to strengthen the spatial feature representation and adopt the ConvLSTM model to learn spatial dependencies adequately. The final forecast results are obtained by stacking strategy fusion in ensemble learning. We conduct experiments on real dengue datasets. The results indicate that STCFM improves prediction accuracy through effective spatiotemporal feature representations and outperforms candidate models with a reasonable component construction strategy. [ABSTRACT FROM AUTHOR]

Objectives. To compare right ventricular thickness (RVT) and deformation of cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM) patients. Methods. Sixty CA (mean age 58 ± 10 years; 33 males (55%)) and sixty HCM patients (mean age 55 ± 14 years; 27 males (45%)) were retrospectively enrolled. RVT, global radical peak strain (GRPS), global longitudinal peak strain (GLPS), and global circumferential peak stain (GCPS) were analyzed. To determine the cutoff values of the RVT and RV strain parameters for distinguishing CA from HCM, the areas under the receiver operating characteristic curve (AUCs) were analyzed. Results. RVT of CA patients was significantly thicker than that of HCM patients (7.8 ± 2.1 vs 5.9 ± 1.3, p < 0.001). Moreover, significantly decreased RV-GRPS (12.1 ± 6.9 vs 23.5 ± 12.1, p < 0.001), RV-GCPS (−3.4 ± 2.2 vs −5.6 ± 3.5, p < 0.001), and RV-GLPS (−4.6 ± 2.3 vs −11.1 ± 4.9, p < 0.001) were observed in CA patients compared with HCM patients. RVT and RV strain demonstrate comparable diagnostic accuracy in differentiating CA from HCM. In particular, RV-GLPS combined with RVT showed the best performance for discriminating CA from HCM (AUC = 0.92, 95% CI: 0.85 to 0.96, p = 0.0001). Conclusions. Right ventricular myocardial thickness and deformation of CA patients was more severe than HCM patients. RV-GLPS combined with RVT presents an excellent diagnostic performance in distinguishing CA and HCM. [ABSTRACT FROM AUTHOR]

Silicene, a single layer of silicon structure, has been predicted to be similar to graphene in physical properties and better than graphene in device applications. Various ways to synthesize silicene have attracted many theoretical and experimental efforts. Controlled epitaxial growth is a possible method. However, a critical growth condition limits the development of various materials. A field ion microscope with the advantages of atomic resolution and many different crystal facets on the emitter sample can provide information about the initial growth of silicon on metal surfaces in various growth conditions. Here, silicon, evaporated by direct current heating of a piece of Si wafer, was deposited onto Ir or Pt tip surfaces held at 400 to 700 K. The p (3 × 2) superstructure of silicon forms on Ir (001) at 400 K. Moreover, Si triangular structure was found on Ir (111) facets, and hexagonal structure was found on Pt (111) facets. [ABSTRACT FROM AUTHOR]

Background Several epidemiological studies have previously investigated the association between the TP53 codon 72 polymorphism and oral squamous cell carcinoma (OSCC) susceptibility; however, current results are inconsistent. We therefore performed this meta-analysis to thoroughly investigate any association among Asian patients. Methods A comprehensive search of PubMed and Embase databases was performed up to December 2013. We only considered studies consisting of patients diagnosed with OSCC by pathological methods. Statistical analyses were performed using Review Manager (RevMan) 5.2 software and odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association. Results A total of 11 case-control studies involving 2,298 OSCC patients and 2,111 controls were included. We found no association between the TP53 codon 72 polymorphism and OSCC susceptibility [(OR = 0.77, 95% CI = 0.48-1.22) for Arg vs. Pro; (OR = 0.67, 95% CI = 0.31-1.43) ArgArg vs. ProPro; (OR = 1.14, 95% CI = 0.97-1.35) ArgPro vs. ProPro; (OR = 0.85, 95% CI = 0.53-1.34) (ArgPro + ArgArg) vs. ProPro; or (OR = 0.34, 95% CI = 0.34-1.23) for ArgArg vs. (ProPro + ArgPro)]. However, subgroup analysis demonstrated an association between the TP53 codon 72 polymorphism and human papillomavirus (HPV)-related OSCC patients. Although statistical heterogeneity was detected, there was no evidence of publication bias. Conclusions Current results suggest that the TP53 codon 72 polymorphism is not associated with OSCC in Asians without the presence of HPV infection. Further research is necessary to determine if such a relationship exists in HPV-related OSCC patients. [ABSTRACT FROM AUTHOR]

Background: Several epidemiological studies have previously investigated the association between the TP53 codon 72 polymorphism and oral squamous cell carcinoma (OSCC) susceptibility; however, current results are inconsistent. We therefore performed this meta-analysis to thoroughly investigate any association among Asian patients. Methods: A comprehensive search of PubMed and Embase databases was performed up to December 2013. We only considered studies consisting of patients diagnosed with OSCC by pathological methods. Statistical analyses were performed using Review Manager (RevMan) 5.2 software and odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association. Results: A total of 11 case-control studies involving 2,298 OSCC patients and 2,111 controls were included. We found no association between the TP53 codon 72 polymorphism and OSCC susceptibility [(OR = 0.77, 95% CI = 0.48-1.22) for Arg vs. Pro; (OR = 0.67, 95% CI = 0.31-1.43) ArgArg vs. ProPro; (OR = 1.14, 95% CI = 0.97-1.35) ArgPro vs. ProPro; (OR = 0.85, 95% CI = 0.53-1.34) (ArgPro + ArgArg) vs. ProPro; or (OR = 0.34, 95% CI = 0.34-1.23) for ArgArg vs. (ProPro + ArgPro)]. However, subgroup analysis demonstrated an association between the TP53 codon 72 polymorphism and human papillomavirus (HPV)-related OSCC patients. Although statistical heterogeneity was detected, there was no evidence of publication bias. Conclusions: Current results suggest that the TP53 codon 72 polymorphism is not associated with OSCC in Asians without the presence of HPV infection. Further research is necessary to determine if such a relationship exists in HPV-related OSCC patients. [ABSTRACT FROM AUTHOR]

The current discharge criteria for COVID-19 require that patients have 2 consecutive negative results for reverse transcription polymerase chain reaction (RT-PCR) detection. Here, we observed that recurrent positive RT-PCR test results in patients with 3 consecutive negative results (5.4%) were significantly decreased compared with those in patients with 2 consecutive negative results (20.6%); such patients reported positive RT-PCR test results within 1 to 12 days after meeting the discharge criteria. These results confirmed that many recovered patients could show a positive RT-PCR test result, and most of these patients could be identified by an additional RT-PCR test prior to discharge. [ABSTRACT FROM AUTHOR]

A ternary clock generator (TCG) is proposed to settle its shortage. The TCG is implemented at the switch level with a simple structure of 24 MOS transistors and simulated at the layout level using the HSPICE software with TSMC 0.18 μm CMOS technology, showing that it works properly. The analyses show that the proposed TCG not only can output a ternary clock of high quality, meeting the clock's design requirements, but also can be fabricated with standard CMOS technology. [ABSTRACT FROM AUTHOR]

• The ESs exhibited obvious spatial heterogeneity with an increasing temporal trend. • The trade-off or synergistic relationships amongst ESs were significant. • In the optimization scenario of 'increase in NPP but not decrease in WY', ESs increased. • Proper allocation of land use can further optimise ESs. The water resources in the arid regions of Northwest China are scarce, and the ecological environment is fragile. Therefore, the evaluation and optimisation of ecosystem services (ESs) in these regions are key to regional ecological security and sustainable development. Few previous studies have incorporated trade-offs and synergies between services provided by various ecosystems into optimal scenario setting constraints. Here, considering the Shule River Basin (SRB) as a typical arid area, we evaluated four ESs, including net primary productivity (NPP), soil conservation (SC), sand retention (SR), and water yield (WY), from 2001 to 2018, and explored their spatiotemporal characteristics. Combining the synergy of ESs and ecological environment protection objectives of the basin, we designed three optimisation scenarios, namely 'maximum probability of land use suitability' (S1), 'increase in NPP without decrease in WY' (S2), and 'increase in NPP without decrease in SC and SR' (S3), based on the cellular automata model to optimise ESs. The four ESs in the SRB showed fluctuating but increasing temporal trends, with the increase in NPP being the most obvious. Moreover, the four ESs exhibited obvious spatial heterogeneity. WY showed synergistic relationships with the other three services, and these relationships became stronger over time. In S1, SC increased, whilst NPP, SR, and WY decreased; in S2, the four ESs increased; and in S3, NPP, SC, and SR increased, whilst WY decreased slightly. Based on the trade-off and synergy of optimised ESs, the scenarios (S2 and S3) in which the services in synergy with NPP do not decrease can improve the ESs as well as weaken the trade-off and strengthen the synergy between them. These findings are used for stakeholders to deepen their understanding of the future consequences associated with today's human activities and decisions, against a range of possible outcomes. [ABSTRACT FROM AUTHOR]

Ecosystem health assessment (EHA) is critical for the effective management of ecosystem services and evaluation of global environmental changes. Here, we explored the spatiotemporal patterns of EH in the Bailong River Basin in a debris flow-prone area from 2000 to 2019 using the VORS model. Net primary productivity, landscape index, land use land cover, water yield, and soil retention data were used to assess the vigor, organization, resilience, and services of the ecosystem. Moreover, using the spatial correlation method and hierarchical cluster analysis, the spatial clustering of and regional differences in EH were investigated in grid and catchment area. In the grid scale, the EH is optimal in the southwest but poor in the northeast. In most areas of the basin, the ecological health index (EHI) showed an increasing trend, and this pattern is expected to continue in the future from 2000 to 2019. The EHI showed significant global spatial correlation and local spatial positive correlation; however, the degree of clustering showed a gradual decline from 2000 to 2019. Based on the results of hierarchical clustering, the catchment area in the basin was divided into four clusters to elucidate regional differences in EH. Areas with high EHI were mainly located in the southern part of the basin, whereas those with low EHI were located in the east of the Wudu District and north of the Tanchang County. Overall, EHA is an important tool to obtain information on the state of the ecosystem, and its findings are fundamental for protecting and improving EH. Therefore, EHA should be incorporated in the decision-making framework for realising effective and appropriate ecosystem management. • The ecosystem health level has increased significantly from 2000 to 2019 in the BRB. • The spatial patterns of ecosystem health were illustrated based on 1984 catchment areas. • The clustering zoning lays a scientific foundation for the implementation of healthy ecosystem management. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of Toona ciliata var. ciliata afforded three new polyynes, -. Their structures were elucidated on the basis of spectroscopic analysis and chemical methods. Only compound exhibited potent cytotoxicity against the HL-60 cell line with an IC value of 6.7±0.27 μ. [ABSTRACT FROM AUTHOR]

An improved spiral compact microstrip resonance cell (SCMRC) structure is proposed in this article. Good low pass performance and wide stopband characteristics can be achieved with a simple single cell, two transmission zeros are introduced within the stopband and thus improve the bandwidth significantly. The measured results of the prototype show that the insertion loss is less than 0.55 dB in the passband, and the bandwidth of the stopband is about 90%, nearly two times of the original SCMRC structure. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 121–124, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22032 [ABSTRACT FROM AUTHOR]

Substrate integrated rectangular waveguide (SIRW) is an artificial rectangular waveguide (RW) constructed in planar substrate with two rows of periodic metallized posts or slots. In this letter, the equivalence formula between the locations of the corresponding short circuits by cylinder walls and by the solid wall was derived, based on the former width equivalence formula of the SIRW and its equivalent RW [(11)]]. The theoretical and simulation results are given for the SIRW short load and RW short load, good agreements have been observed. Such equivalences are convenient for the design of small waveguides, of millimeter wave, in a multilayer circuit structure, such as the LTCC etc. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1694–1698, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21805 [ABSTRACT FROM AUTHOR]

[Display omitted] • A Janus-engineered interconnecting layer (ICL) for organic tandem solar cell. • The ICL consists a ZnO thin layer with both sides modified by different SAMs. • Charges recombination occurred at ICL through a "Broken-gap junction". • The ICL is simple to fabricate so multiple sub-cells can be stacked up easily. • We demonstrated a 2.2 V tandem cell consisting of four sub-cells using our ICL. [ABSTRACT FROM AUTHOR]

• A novel double-string-spun rotor is proposed for realizing vibration-to-rotation conversion. • The rotor achieves high rotation speeds under low-frequency excitations. • An electromagnetic generator based on the rotor attains strikingly high power density. • The generator can efficiently exploit low-frequency vibrations and irregular human body motions. • The generator can sustain the normal operation of various commercial electronics. The pervasive low-frequency mechanical energy is important for realizing self-powered electronics, but its efficient exploitation is still a highly challenging task due to the mismatch between the motion frequencies and the working frequencies of already reported energy harvesters. To tackle this issue, we propose in this paper a new motion-conversion mechanism (which we name 'double-string-spun rotor') to transform low-frequency motions (mechanical vibrations and irregular human body motions) to uni-directional and high-speed rotation. Consisting of a rotatable shaft and a ratchet, the rotor structure first converts low-frequency motions to bi-directional rotation of the shaft through two strings and then drives the ratchet to do uni-directional rotation via curved plectra. The promising application of the rotor in capturing low-frequency mechanical energy is examined through an electromagnetic generator (harvester) constructed with the rotor, which generates 46 mW power when actuated by a crank-slider mechanism at 7 Hz. The generator has also been utilized to scavenge irregular human body motions and low-frequency vibrations engendered by daily jogging, and the collected energy allows the continuous work of various commercial electronics. This study provides a new strategy for efficiently exploiting ambient low-frequency motions and exhibits the high probability of realizing self-sustained electronics with the captured low-frequency mechanical energy. [ABSTRACT FROM AUTHOR]

Background: The effect of brachytherapy on lymphocytes and cytokines in the tumor microenvironment is unclear. This study aimed to analyze the relationship between the invasion of lymphocytes and cytokines in the tumor microenvironment and the interval after single brachytherapy hypofractionated radiotherapy (SBHFRT) and conventional fractionation radiotherapy (CFRT) in non-small cell lung cancer (NSCLC).Methods: Lewis tumor-bearing mice were randomly divided into control, CFRT, and SBHFRT groups. On days 7 and 14 after radiation, the expression levels of CD86+, CD4+, CD8+, and Foxp3+ cells, and levels of Ki-67+ protein were detected by immunohistochemistry, and the tumor necrosis rate was calculated. Following this, the levels of interleukin-10 (IL-10), IL-12, and interferon-γ (IFN-γ) were detected by enzyme-linked immunosorbent assay. The apoptosis rate was evaluated via flow cytometry. The tumor volume and tumor growth inhibition rate (TGIR) were calculated on day 14. Tumor metabolism was assessed via 18F-FDG micropositron emission tomography/computer tomography.Results: The tumor volume reduced by 22.0% and TGIR increased by 92.2% (p < 0.05) in the SBHFRT group. Further, on days 7 and 14 after radiation, tumor metabolism, Ki-67+ and Foxp3+ expression levels, and IL-10 levels were lower, and tumor necrosis and apoptosis rates; CD86+, CD4+, and CD8+ expression levels; and IL-12 and IFN-γ levels were higher in the SBHFRT group than in the CFRT group, particularly on day 7.Conclusion: SBHFRT could lead to more accumulation of dendritic cells, anti-tumor lymphocytes, and cytokines, and further reduce the aggregation of immunosuppressive lymphocytes and cytokines in the tumor microenvironment compared with CFRT, and the difference was the most obvious on day 7 after radiation. The clinical significance of the findings remains to be further verified. [ABSTRACT FROM AUTHOR]