Description: A simple two-step method was employed for preparing nano-sized gold nanoparticles-graphene composite to construct a GNPs-GR-SDS modified electrode. Hemoglobin (Hb) was successfully immobilized on the surface of a basal plane graphite (BPG) electrode through a simple dropping technique. Direct electrochemistry and electrocatalysis of the hemoglobin-modified electrode was investigated. The as-prepared composites showed an obvious promotion of the direct electro-transfer between hemoglobin and the electrode. A couple of well-defined and quasi-reversible Hb CV peaks can be observed in a phosphate buffer solution (pH 7.0). The separation of anodic and cathodic peak potentials is 81 mV, indicating a fast electron transfer reaction. The experimental results also clarified that the immobilized Hb retained its biological activity for the catalysis toward NO. The biosensor showed high sensitivity and fast response upon the addition of NO, under the conditions of pH 7.0, potential ‒0.82 V. The time to reach the stable-state current was less than 3 s, and the linear response range of NO was 0.72–7.92 μM, with a correlation coefficient of 0.9991.

Description: Human papillomavirus (HPV) are firmly established as the principal causative agent for cervical carcinoma. Current vaccines may provide some protection for women from cervical carcinoma linked to HPV genotype 16 and 18. This may be the best vaccine for Western women, but the geographical variation in HPV distributions may not make it the most appropriate vaccine for China or Asia. This study provided an observational, retrospective, hospital-based cross-sectional study on the distribution of HPV genotypes among 5410 women with invasive cervical cancer (ICC) or cervical intraepithelial neoplasia (CIN). Overall, the positive rates of the four HPV types included in current prophylactic vaccines were counted, the two high-risk types (HPV-16 and -18) covered by current vaccines represented 66.9% of women with squamous cancer, 55.0% with adenocarcinoma, 64.9% with adenosquamous carcinoma and 77.4% of other type ICC, as well as 59.5% of CIN III, 45.0% of CIN II and 38.1% of CIN I cases. As expected, two low-risk types (HPV-6 and -11) included in the quadrivalent vaccine did not show good coverage data. Particularly worth mentioning is the fact that the addition of HPV-52 and -58 to the vaccine cocktail would increase cancer protection in our population, potentially preventing up to beyond 16% of squamous/adenosquamous carcinoma and other type of cervical cancers, and 7.75% of adenocarcinomas. It might also potentially reduce the rate of CIN III by a further 28.6% and CIN II and I by a third. This study established the baseline for surveillance in Zhejiang Province, and provides data for further vaccine designs: a quadrivalent HPV vaccine covering HPV-16/-58/-18/-52, would be more welcome in our region in the forthcoming year compared to the currently available vaccine.

Description: Precise Point Positioning (PPP) makes use of the undifferenced pseudorange and carrier phase measurements with ionospheric-free (IF) combinations to achieve centimeter-level positioning accuracy. Conventionally, the IF ambiguities are estimated as float values. To improve the PPP positioning accuracy and shorten the convergence time, the integer phase clock model with between-satellites single-difference (BSSD) operation is used to recover the integer property. However, the continuity and availability of stand-alone PPP is largely restricted by the observation environment. The positioning performance will be significantly degraded when GPS operates under challenging environments, if less than five satellites are present. A commonly used approach is integrating a low cost inertial sensor to improve the positioning performance and robustness. In this study, a tightly coupled (TC) algorithm is implemented by integrating PPP with inertial navigation system (INS) using an Extended Kalman filter (EKF). The navigation states, inertial sensor errors and GPS error states are estimated together. The troposphere constrained approach, which utilizes external tropospheric delay as virtual observation, is applied to further improve the ambiguity-fixed height positioning accuracy, and an improved adaptive filtering strategy is implemented to improve the covariance modelling considering the realistic noise effect. A field vehicular test with a geodetic GPS receiver and a low cost inertial sensor was conducted to validate the improvement on positioning performance with the proposed approach. The results show that the positioning accuracy has been improved with inertial aiding. Centimeter-level positioning accuracy is achievable during the test, and the PPP/INS TC integration achieves a fast re-convergence after signal outages. For troposphere constrained solutions, a significant improvement for the height component has been obtained. The overall positioning accuracies of the height component are improved by 30.36%, 16.95% and 24.07% for three different convergence times, i.e., 60, 50 and 30 min, respectively. It shows that the ambiguity-fixed horizontal positioning accuracy has been significantly improved. When compared with the conventional PPP solution, it can be seen that position accuracies are improved by 19.51%, 61.11% and 23.53% for the north, east and height components, respectively, after one hour convergence through the troposphere constraint fixed PPP/INS with adaptive covariance model.

Description: Automatic target recognition (ATR) in synthetic aperture radar (SAR) images plays an important role in both national defense and civil applications. Although many methods have been proposed, SAR ATR is still very challenging due to the complex application environment. Feature extraction and classification are key points in SAR ATR. In this paper, we first design a novel feature, which is a histogram of oriented gradients (HOG)-like feature for SAR ATR (called SAR-HOG). Then, we propose a supervised discriminative dictionary learning (SDDL) method to learn a discriminative dictionary for SAR ATR and propose a strategy to simplify the optimization problem. Finally, we propose a SAR ATR classifier based on SDDL and sparse representation (called SDDLSR), in which both the reconstruction error and the classification error are considered. Extensive experiments are performed on the MSTAR database under standard operating conditions and extended operating conditions. The experimental results show that SAR-HOG can reliably capture the structures of targets in SAR images, and SDDL can further capture subtle differences among the different classes. By virtue of the SAR-HOG feature and SDDLSR, the proposed method achieves the state-of-the-art performance on MSTAR database. Especially for the extended operating conditions (EOC) scenario “Training 17 ∘ —Testing 45 ∘ ”, the proposed method improves remarkably with respect to the previous works.

Description: Energies, Vol. 11, Pages 1790: Infeasibility Analysis of Half-Wavelength Transmission Systems Energies doi: 10.3390/en11071790 Authors: Zheng Xu Jian Yang Nengjin Sheng This paper analyzes the infeasibility of half-wavelength transmission systems in the aspects of power-frequency overvoltage and synchronization stability. The circuit model of the long-distance transmission system is established at first for steady-state and transient analysis. The sending-end system and the receiving-end system are both considered in the model. A test system based on an actual transmission line is given to facilitate the description of system characteristics. Based on the circuit model, the resonant transmission distance of the system is found and calculated. Theoretical analysis and numerical calculations are carried out to determine the feasibility transmission distance. It is demonstrated that the transmission distance should be in a certain range, which is larger than the resonant transmission distance, to satisfy the steady-state overvoltage and the small signal synchronization stability as well as the frequency deviation constraints. For transmission distances in the feasible range, the three-phase short circuit fault at a certain point of the transmission line will cause the most serious transient power-frequency overvoltage, and the system is very likely to lose synchronization stability. Considering the transient power-frequency overvoltage and the transient synchronization stability, the half-wavelength transmission system is technically impossible to operate.

Description: Sensors, Vol. 18, Pages 2761: A Novel Coordinated Motion Fusion-Based Walking-Aid Robot System Sensors doi: 10.3390/s18092761 Authors: Wenxia Xu Jian Huang Lei Cheng Human locomotion is a coordinated motion between the upper and lower limbs, which should be considered in terms of both the user’s normal walking state and abnormal walking state for a walking-aid robot system. Therefore, a novel coordinated motion fusion-based walking-aid robot system was proposed. To develop the accurate human motion intention (HMI) of such robots when the user is in normal walking state, force-sensing resistor (FSR) sensors and a laser range finder (LRF) are used to detect the two HMIs expressed by the user’s upper and lower limbs. Then, a fuzzy logic control (FLC)-Kalman filter (LF)-based coordinated motion fusion algorithm is proposed to synthesize these two segmental HMIs to obtain an accurate HMI. A support vector machine (SVM)-based fall detection algorithm is used to detect whether the user is going to fall and to distinguish the user’s falling mode when he/she is in an abnormal walking state. The experimental results verify the effectiveness of the proposed algorithms.

Description: Regular maintenance of non-communicable chronic diseases can constrain disease progression in diabetic and hypertensive patients. To identify the individual and social factors that are associated with positive health-seeking behaviors and regular maintenance of chronic diseases, we have conducted a follow up study in 2015 on diabetic and hypertensive patients in Hubei Province. We used binary logistic regression models to determine specific factors associated with diabetic and hypertensive patients that sought healthcare services for their conditions in accordance with current Chinese Centers for Disease Prevention and Control (CDC) guidelines. Our findings show that 42.16% of 510 people living with chronic conditions (PLCDs) sought health services in line with existing guidelines. Findings also show a higher probability (8.418 times) for PLCDs seeking healthcare services at higher-tiered hospitals (secondary and tertiary hospitals) than for PLCDs seeking care at primary hospitals (odds ratio (OR) = 8.418, 95% confidence interval (CI) = 4.82, 14.27, p 〈 0.001). These analyses underscore the importance of having patient advocates who can provide support, where necessary, and encourage positive health-seeking behavior. The study also shows a negative impact on regular maintenance for PLCDs in households with high financial constraints. In contrast, the study shows positive impacts for increased household income, age, and residency in rural locations. In sum, this study underscores the importance of primary hospitals as key points of care and critical players in care coordination for PLCDs. The study provides more evidence for Chinese policymakers seeking to contain costs and improve population health. The findings also underscore the need for community-based interventions, specifically interventions that link local primary hospitals, friends/family members, and PLCDs.

Description: Desde la fundación de la República Popular China el Gobierno Central ha estado buscando la vía más adecuada para conseguir el desarrollo regional. En el período de Mao el enfoque adoptó una perspectiva principalmente administrativa, tratando de mejorar la estructura de división y de gobierno del país. Con el inicio del período de reforma y apertura, el acento cambia al diseño de estrategias de desarrollo regional, aunque con tendencias cambiantes que van desde las políticas redistributivas hasta el modelo de desarrollo asimétrico, y los esfuerzos por combatir las desigualdades entre regiones y entre áreas urbanas y rurales de China. Este artículo realiza una revisión de los cambios producidos en China a través de todos estos procesos de regionalización, proporcionando un marco de referencia para comprender las diferentes etapas y ayudar a estudios más específicos sobre este país. [fr] À partir de la fondation de la République populaire de Chine le gouvernement central a cherché le moyen le plus approprié pour atteindre le développement régional. Dans la période de Mao l'approche essentiellement adoptée fut un point de vue administratif, en essayant d'améliorer la structure de la division et le gouvernement du pays. Avec le début de la réforme et la période d'ouverture, les directives changent vers la conception de stratégies de développement régional, mais avec une évolution des tendances allant depuis les politiques de redistribution jusqu'au modèle de développement asymétrique, et les efforts pour lutter contre les inégalités entre les régions et entre les zones urbaines et rurales de La Chine. Cet article passe en revue les changements en Chine à travers tous ces processus de régionalisation, en fournissant un cadre pour comprendre les différentes étapes et pour aider les études plus spécifiques sur ce pays.