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The multi-degree-of-freedom characteristics of the planetary gear electronic continuously variable transmission (ECVT) configuration in series-parallel hybrid tractors impose more complex requirements for energy management strategies under variable load conditions. For a high-power hybrid tractor, this paper takes the hybrid tractor output-split (OS)-ECVT configuration as the research object and describes the principles of stepless transmission and power-splitting within the configuration. In order to improve the fuel economy of high-power hybrid tractors and the running status of power components, an energy management strategy focused on ploughing conditions based on the Bellman minimum dynamic programming (DP) algorithm is proposed in this paper. Second, equivalent fuel consumption is selected as the performance index for energy-saving control, and the solving principle of the energy management strategy based on the dynamic programming algorithm is established to facilitate the resolution process of the energy management strategy. Finally, the energy-saving control simulation is completed under ploughing conditions. The results show that compared with the energy management strategy based on the optimal operating line (OOL), the energy management strategy based on DP fully utilizes the benefits of low-cost electric energy and enables the hybrid power system to have a wider range of stepless transmission performance. In addition, the hybrid power system has the advantages of enhanced decoupling of speed and torque, higher efficiency, and more economical secondary energy conversion. As a result, the whole machine has enhanced power-split performance, greatly improving the running conditions of the power components. The equivalent fuel consumption values of the energy management strategies based on DP and OOL are about 3.1238 L and 4.2713 L, respectively. The equivalent fuel consumption based on DP is reduced by about 26.87%, which effectively improves the fuel efficiency of hybrid tractors. [ABSTRACT FROM AUTHOR]

Oral lichen planus (OLP) is a common chronic inflammatory disease of the oral mucosa, the mechanism of its inflammatory progression has not yet been fully elucidated. PA28γ plays a significant role in a variety of immune‐related diseases. However, the exact role of PA28γ in the pathogenesis of OLP remains unclear. Here, we demonstrated that PA28γ is overexpressed in epithelial cells and inflammatory cells of OLP tissues but has no significant relationship with OLP subtypes. Functionally, keratinocytes with high PA28γ expression could induce dendritic cell (DC) maturation and promote the T‐cell differentiation into Th1 cells in response to the immune response. In addition, we found that a high level of PA28γ expression is associated with high numbers of infiltrating mature DCs and activated T‐cells in OLP tissues. Mechanistically, keratinocytes with high PA28γ expression could promote the secretion of C–C motif chemokine (CCL)5, blocking CCL5 or/and its receptor CD44 could inhibit the induction of T‐cell differentiation by keratinocytes with high PA28γ expression. In conclusion, we reveal that keratinocytes with high expression of PA28γ in OLP can induce DC maturation and promote T‐cell differentiation through the CCL5‐CD44 pathway, providing previously unidentified mechanistic insights into the mechanism of inflammatory progression in OLP. [ABSTRACT FROM AUTHOR]

Owing to the increasing need for green synthesis and environmental protection, the utilization of biological organism‐derived carbons as supports for noble‐metal electrocatalysts has garnered public interest. Nevertheless, the mechanism by which microorganisms generate nanometals has not been fully understood yet. In the present study, we used genetically engineered bacteria of Shewanella oneidensis MR‐1 (∆SO4317, ∆SO4320, ∆SO0618 and ∆SO3745) to explore the effect of surface substances including biofilm‐associated protein (bpfA), protein secreted by type I secretion systems (TISS) and type II secretion systems (T2SS), and lipopolysaccharide in microbial synthesis of metal nanoparticles. Results showed Pd/∆SO4317 (the catalyst prepared with the mutant ∆SO4317) shows better performance than other biocatalysts and commercial Pd/C, where the mass activity (MA) and specific activity (SA) of Pd/∆SO4317 are 3.1 and 2.1 times higher than those of commercial Pd/C, reaching 257.49 A g−1 and 6.85 A m−2 respectively. It has been found that the exceptional performance is attributed to the smallest particle size and the presence of abundant functional groups. Additionally, the absence of biofilms has been identified as a crucial factor in the formation of high‐quality bio‐Pd. Because the absence of biofilm can minimize metal agglomeration, resulting in uniform particle size dispersion. These findings provide valuable mechanical insights into the generation of biogenic metal nanoparticles and show potential industrial and environmental applications, especially in accelerating oxygen reduction reactions. [ABSTRACT FROM AUTHOR]

Objectives: Oral lichen planus, a chronic inflammatory immune disease, occurs in the oral mucosa. We aimed to assess the prevalence and possible influencing factors of oral lichen planus in patients with diabetes mellitus. Subjects and Methods: This cross‐sectional study involved 525 patients with diabetes mellitus and 525 controls. We collected information on blood glucose level, duration of diabetes, diabetic complications, treatment methods, other systemic diseases and medication history. Results: Oral lichen planus was significantly more prevalent in the diabetes mellitus/type 2 diabetes mellitus group than in the controls (2.3%/2.2% vs. 0.6%, p = 0.019/0.022). There was no significant association between patients with diabetes mellitus with and those without oral lichen planus in age (p = 0.195), sex (p = 0.390), blood glucose level (p = 1), duration of diabetes (p = 0.638), diabetic complications (p = 1), treatment methods (p = 0.962), other systemic diseases (p = 0.891) and medication history (p = 0.848). Conclusions: Diabetes mellitus was associated with oral lichen planus; there was a higher prevalence of oral lichen planus in patients with diabetes mellitus/type 2 diabetes mellitus than in those without diabetes. Oral lichen planus development in patients with diabetes mellitus was not significantly associated with age, sex, blood glucose level, duration of diabetes, diabetic complications, treatment methods, other systemic diseases and medication history. [ABSTRACT FROM AUTHOR]

In order to study the energy distribution of the tandem hybrid tractor and achieve optimal fuel economy under the whole operating condition, an energy distribution strategy based on PMP (Pontryagin minimum principle) is proposed. The performance parameters of the relevant power components are obtained by constructing the test bench of the tandem hybrid tractor. At the same time, the mathematical model of energy distribution is established from the aspects of energy distribution objective function, state variable, and variable constraint. Based on the external characteristic test of the hub motor and the resistance analysis, the transport operation condition of the tractor is selected as the simulation target condition. The ADVISOR2002 and Simulink software are used to jointly simulate the three energy distribution strategies: the thermostat type, the power-following type, and the PMP type. The simulation results show that, compared with the other two, the fuel economy and battery power loss of the PMP-based energy distribution strategy are significantly improved. The fuel consumption per 100 km is decreased by 32.91% and 26.10%, respectively, which verifies the feasibility of the strategy. This study is of great significance for improving the production efficiency and reducing fuel consumption of hybrid tractors. [ABSTRACT FROM AUTHOR]

The development of efficient catalysts for proton exchange membrane fuel cells (PEMFCs) is crucial for their commercial viability. This study introduces a method for synthesizing Pd nanoparticles on carbon supports as electrocatalysts using microbial synthesis, specifically employing the bacterium Shewanella oneidensis MR-1. The so-produced catalysts exhibit enhanced catalytic activity and stability for the oxygen reduction reaction (ORR). The microbial synthesis approach offers advantages, such as high purity, cost-effectiveness, and environmental friendliness. Additionally, the use of sodium alginate (SA) hydrogel in the synthesis process further improves the catalyst's performance due to its metal chelating properties. The resulting Pd/C electrocatalysts, especially those synthesized with a composite matrix of SA and CaCO3, demonstrate superior ORR performances outperforming that of commercial Pd/C catalysts. It was found that the composite substrate affected the palladium recovery rate, whose increasing palladium absorption, refined particle size, improved graphitization degree, and increasing pyridinic-N of the resultant catalyst synergistically enhanced the availability of active centers that eventually contributed to the superior ORR performances. This research paves the way for the development of high-performance and cost-effective catalysts for PEMFCs. [ABSTRACT FROM AUTHOR]

Traditional tractors can only achieve steering through mechanical structures such as steering knuckles and steering trapezoids. Among them, the mechanical structure is more complex, and various parts are easily damaged, making the tractor malfunction. The four-wheel independent drive differential steering mode differs from the traditional Ackermann steering mode, which realizes steering by controlling the inner and outer wheel torque, which can accurately steer the working state of high-end agricultural machinery equipment and improve the operating efficiency of agricultural machinery equipment. Aiming at the dynamic control problem in the steering of electric tractor four-wheel independent drive, a layered control strategy based on the sliding mode control of yaw torque at the upper level and the optimal torque distribution level based on the mean load rate of vehicle tires at the lower was proposed. By analyzing the differential steering mechanism of a four-wheel independent drive, a dynamic model of differential steering of the electric tractor is established, and a dynamic controller of a four-wheel independent drive is designed according to the layered control strategy. The upper controller tracks and controls the expected yaw speed on the basis of the sliding mode control to track the driver's intention, and the lower controller realizes the optimal torque distribution based on the principle of the optimal average load rate of the vehicle tire to ensure the steering stability of the electric tractor. The effect of the controller was simulated and analyzed under typical conditions of double line shift, serpentine, and step. The results showed that the sliding mode controller is better than the PID controller in driver intention tracking. Compared with the average allocation strategy, the average maximum load rate of the vehicle tire under the three working conditions is reduced by 16.9%, 13.8%, and 17.3%, respectively, which proves the effectiveness of the layered control strategy. In the real car test, the sliding mode controller is better than the PID controller in the driver intention tracking. This study has important guiding significance for improving the maneuverability and stability of electric tractors. [ABSTRACT FROM AUTHOR]

Although it is generally accepted by the perovskite solar cells community that their interface behaviors have a profound impact on their power conversion efficiency (PCE) and stability, such interfacial engineering on the bottom interface between electron transport layer (ETL) and perovskite film is still lagging. Herein, a 3D graphene (G)–CuInS2 composite is designed as an efficient ETL to improve both the interfacial contact and passivate defects at the G–CuInS2/perovskite interface. The lattice matching of graphene and methylammonium lead iodide CH3NH3PbI3 inhibits the concentrated stress generated during the growth of perovskite, resulting in crystal films with large grain boundaries. The low‐electron defect density in 3D G–CuInS2 composite facilitates the electron transport from perovskite film to CuInS2 quantum dots. In addition, 3D G–CuInS2 shows excellent carrier extraction capability of reducing carrier extraction time by 1.47 times than that of the counterpart. Correspondingly, a highly improved PCE of 22.4% is obtained, which increases by 15% of the counterpart. Furthermore, the unencapsulated device based on 3D G–CuInS2 shows long‐term stability, maintaining 85% of its original efficiency in air for 30 days. This strategy provides a new route to interfacial passivation engineering for preparation of high‐performance perovskite solar cells. [ABSTRACT FROM AUTHOR]

To obtain the load spectrum of the traction resistance of the three-point suspension device under tractor-plowing conditions, a load spectrum extrapolation method based on a genetic algorithm optimal threshold selection is proposed. This article first uses a pin force sensor to measure the plowing resistance of the tractor's three-point suspension device under plowing conditions and preprocesses the collected load signal. Next, a genetic algorithm is introduced to select the threshold based on the Peak Over Threshold (POT) extremum extrapolation model. The Generalized Pareto Distribution (GPD) fits the extreme load distribution that exceeds the threshold range, generating new extreme points that follow the GPD distribution to replace the extreme points in the original data, achieving the extrapolation of the load spectrum. Finally, the loading spectrum that can be achieved on the test bench is obtained based on the miner fatigue theory and accelerated life theory. The results show that the upper threshold of the time-domain load data obtained by the genetic algorithm is 10.975 kN, and the grey correlation degree is 0.7249. The optimal lower threshold is 8.5455 kN, the grey correlation degree is 0.7722, and the fitting effect of the GPD distribution is good. The plowing operation was divided into five stages: plowing tool insertion, acceleration operation, constant speed operation, deceleration operation, and plowing tool extraction. A traction resistance loading spectrum that can be achieved on the test bench was developed. The load spectrum extrapolation method based on the genetic algorithm optimal threshold selection can improve the accuracy of threshold selection and achieve the extrapolation and reconstruction of the load spectrum. After processing the extrapolated load spectrum, it can be transformed into a load spectrum that can be recognized by the test bench. [ABSTRACT FROM AUTHOR]

Electrochemical detection (ECD) technique has been deemed to be an effective method for detection. However, low sensitivity and poor anti-interference ability restrict its widespread use in quercetin detection. Herein, a coral reef-like Pt-decorated MXene composite is developed to construct a sensitive Pt-MXene/GCE electrode to achieve accurate detection for quercetin. The multilayer structure of MXene in the complex provides sufficient active sites for the electrochemical reaction and promotes electron transfer, leading to reduction in electrochemical impedance. The electrochemical behavior of quercetin on the Pt-MXene/GCE electrode reveals that the electrochemical redox process involves the participation of the two-electron/double-proton reaction process. As expected, the Pt-MXene/GCE electrode exhibits excellent stability, repeatability, reproducibility, and selectivity and shows accurate detection ability in actual application. In addition, the Pt-MXene/GCE electrode possesses a low limit of detection and high sensitivity, which is superior than most of the previous reports. This work provides a promising strategy for selective ECD of quercetin, which would give guidance for the fabrication of a highly selective sensor with outstanding sensitivity. [ABSTRACT FROM AUTHOR]

This paper has taken a 25-horsepower tractor as the object and developed a distributed drive electric tractor (DDET), which may be applied to farms in paddy and upland fields. First, we designed the structure of the chassis drive system in the DDET, then analyzed the dynamic performances, built an evaluation index of dynamic performance for the DDET, and researched the influencing factors of dynamic performances. Moreover, we built the simulation model and studied the dynamic performance based on Advisor software in different working conditions. Finally, we developed the testing tractor of the DDET for test verification. Results show that the traction of DDET is about 5400 N, and the time from being static to being accelerated to a maximum speed of 28.15 km/h is about 5.5279 s. The theoretical analysis results, simulation results, and testing tractor verification results of the DDET designed in this paper are basically consistent, and the overall dynamic performance of the DDET is good. [ABSTRACT FROM AUTHOR]

Noble-metal electrocatalysts supported by biological-organism-derived carbons have attracted attention from the public due to the growing demands for green synthesis and environmental protection. Carbonization at high temperatures and hydrogen reduction are critical steps in this technical route. Herein, Shewanella oneidensis MR-1 were used as precursors, and the effects of the hydrogen-reduction procedure on catalysts were explored. The results showed that the performances of FHTG (carbonization followed by hydrogen reduction) displayed the best performance. Its ECSA (electrochemical surface area), MA (mass activity), and SA (specific activity) reached 35.01 m2 g−1, 58.39 A·g−1, and 1.66 A cm−2, respectively, which were 1.17, 1.75, and 1.50 times that of PHTG (prepared through hydrogen reduction followed by carbonization) and 1.56, 2.26, and 1.44 times that of DHTG (double hydrogen reduction). The high performance could be attributed to its fine particle size and rich N content, and the specific regulation mechanism was also proposed in this paper. This study opens a practical guide for effectively avoiding particle agglomeration during the fabrication process for catalysts. [ABSTRACT FROM AUTHOR]

Objective: To examine the comparative efficacy and safety of topical administration for oral lichen planus. Materials and Methods: An electronic database search (1st January 1946 to 1st May 2020) for randomised controlled trials identified 34 studies involving eight interventions (clobetasol, betamethasone, triamcinolone, dexamethasone, fluocinolone, tacrolimus, pimecrolimus, and cyclosporine); these studies were subjected to network meta‐analysis using direct and indirect comparisons [efficacy indicators: clinical response rate, symptom‐reducing effect (visual analogue scale score), sign‐reducing effect (Thongprasom‐scale score) and relapse; safety indicator: adverse event occurrence]. Results: Compared with placebo, tacrolimus had the best clinical response rate (odds ratio (OR), 57.78 [95% CI 3.15–1060.52]; P–score, 0.8654) and cyclosporine had the worst (OR, 3.61[95% CI 0.20–66.62]; P–score, 0.2236); tacrolimus had the best symptom‐reducing effect (standardised mean difference (SMD), 1.06 [95% CI 0.41–1.71]; P–score, 0.9323) and fluocinolone had the worst (SMD, −0.54 [95% CI −1.44–0.36]; P–score, 0.0157); dexamethasone had the best sign‐reducing effect (SMD, 3.60 [95% CI 1.74–5.45]; P–score, 0.8306) and clobetasol had the worst (SMD, 2.63 [95% CI 1.66–3.61]; P–score, 0.2581); and pimecrolimus performed best (OR, 0.04 [95% CI 0.00–0.64]; P–score, 0.9227) and clobetasol performed the worst [OR, 0.60; 95% CI 0.15–2.45; P–score, 0.2545] in reducing relapse. Regarding safety, dexamethasone was the safest compared with placebo [OR, 0.37; 95% CI 0.05–2.57; P–score, 0.9337), whereas fluocinolone ranked low for safety [OR, 9.48; 95% CI 1.50– 60.03; P–score, 0.1189]. Conclusions: The relative ranking of topical administration varies according to the different indicators. Based on the joint consideration of clinical response rate and adverse event occurrence, dexamethasone, triamcinolone and betamethasone are recommended for better efficacy and safety. The optimal treatment for oral lichen patients varies under different conditions. [ABSTRACT FROM AUTHOR]

A novel oxygen reduction reaction (ORR) electrocatalyst silver@platinum-cobalt-rGO nanoflower (Ag@PtCo-rGO NFs) is prepared by hydrothermal reduction method. The formation of silver chloride likes elm leaf microstructure in the reaction process, performing as a template. The Ag@PtCo-rGO NFs exhibit excellent electrocatalytic activity, whose specific activity is 9 times higher than that of commercial Pt/C. More importantly, Ag@PtCo-rGO NFs demonstrate excellent durability than JM Pt/C for ORR in acid media, as evidenced by accelerated durability test after 40,000 cycles. These excellent performances can be attributed to the special structure, atomic steps and synergistic effect between Pt, Ag and Co. The density functional theory calculation shows that Ag@PtCo has the best activity, which is related to the transition state for O–O bond. This work proposes a promising pathway for the synthesis of surfactant-free nanoflowers structure catalysts with high catalytic performance and low cost. [Display omitted] • This method prepares nanoflowers without external templates and surfactants. • The SA is 9 times larger than that of commercial Pt/C. • The catalysts exhibit excellent durability after 40,000 cycles. [ABSTRACT FROM AUTHOR]

Shape-tunable PtAg nanocatalysts including PtAg nanoflowers (NFs) and PtAg nanowires (NWs) are prepared by a facile hydrothermal reduction method, via adjusting the precursor ratio of Pt/Ag and subsequent UV-irradiation. Physicochemical characterizations reveal that the as-prepared catalysts have a porous structure, which forms from the conversion of AgCl to Ag nanoparticles. These features favor both oxygen mass transfer and accessibility of active sites. The as-prepared Pt 1 Ag 4 NWs exhibit superior catalytic performances for ORR. The mass activity of Pt 1 Ag 4 NWs is 11.4 times higher than that of 20% Pt/C. More important, the electrochemically active surface area (ECSA) of Pt 1 Ag 4 NWs is 2.5 times larger than that of commercial Pt/C. Image 1 • A feasible way to prepare PtAg catalysts with structural tunability. • UV-irradiation further optimizes our catalyst material. • Pt 1 Ag 4 NWs exhibit highest catalytic performances for ORR. [ABSTRACT FROM AUTHOR]

While noble metals loaded on carbon-based supports are commonly used as oxygen reduction catalysts for fuel cell cathodes, the preparation process is complicated and expensive cost. In this paper, Pd2+ was first adsorbed on Shewanella by its adsorption characteristics, then the Pd supported on Shewanella catalyst was obtained after carbonization at 600 °C and hydrogen reduction at 200 °C. The Shewanella cells retain the rod shape of bacteria following pyrolysis under high temperatures, while N and Pd heteroatoms are uniform distribution on the carbon matrix. As a result, Pd supported on Shewanella catalyst exhibits excellent electrocatalytic activity for ORR via a dominant four-electron oxygen reduction pathway in alkaline medium. More importantly, the mass activity of the prepared catalyst was 5.8 times higher than that of commercial Pd/C, and its stability was also better than the Pd/C, which could be promising alternatives to costly Pt-based electrocatalysts for ORR. Image 1 • Synthesizing Pd catalysts supported on bacterium is facile and eco-friendly. • Nitrogen doping can enhance the catalyst performance. • The close contact between HNC and Pd can improve catalyst activity and stability. • Pd/HNC catalysts show outstanding activity and stability than standard Pd/C. [ABSTRACT FROM AUTHOR]

Featured Application: The paper proposes a novel method of calibrating system parameters for a PMD (phase measuring deflectometry) based system. This calibration method can be used in the areas of reverse engineering, car industry and aerospace industry. Phase measuring deflectometry has been widely studied as a way of obtaining the three-dimensional shape of specular objects. Recently, a new direct phase measuring deflectometry technique has been developed to measure the three-dimensional shape of specular objects that have discontinuous and/or isolated surfaces. However, accurate calibration of the system parameters is an important step in direct phase measuring deflectometry. This paper proposes a new calibration method that uses phase information to obtain the system parameters. Phase data are used to accurately calibrate the relative orientation of two liquid crystal display screens in a camera coordinate system, by generating and displaying horizontal and vertical sinusoidal fringe patterns on the two screens. The results of the experiments with an artificial specular step and a concave mirror showed that the proposed calibration method can build a highly accurate relationship between the absolute phase map and the depth data. [ABSTRACT FROM AUTHOR]

This letter proposes a simplified zero‐voltage switching (ZVS) detection circuit and switching loss dynamic optimisation method. The proposed circuit and tuning method can automatically adjust the switching frequency of a synchronous buck converter to work in critical current mode to realise ZVS under a wide load range. The advantages of the proposed circuit and method are that ZVS detection and switching loss dynamic optimisation can be realised by only one ZVS detection circuit, which simplifies the detection circuit, further improves the power density and reduces the number of analogue‐to‐digital conversion channels of the digital signal processor. A prototype of the synchronous buck converter with a rated input voltage of 100 V is established to verify the effectiveness of the proposed ZVS detection circuit and switching loss dynamic optimisation method. By using the proposed detection circuit and optimisation method, the switching loss of the MOSFETs has been greatly reduced and an efficiency improvement of nearly 1% at peak output power has also been achieved. [ABSTRACT FROM AUTHOR]

Abstract A novel platinum-palladium/carbon nanowires (PtPd/CNWs) catalysts are successfully prepared by electrospinning for the oxygen reduction reaction (ORR). The prepared PtPd/CNWs catalysts exist in the form of membrane, which can be directly applied as catalyst layer in membrane electrode assembly. The ORR activity of binary PtPd/CNWs catalysts are enhanced significantly in comparison to the ternary platinum-palladium-gold/carbon nanowires (PtPdAu/CNWs) catalysts and 20% Pt/C. Here, the gold in PtPdAu/CNWs mainly exists in larger gold nanoparticles rather than in the form of ternary alloy with Pt, Pd. The mass activity and special activity of PtPd/CNWs are 4.230 times and 4.225 times than that of 20% Pt/C, respectively. Moreover, the electrochemical active surface areas (ECSAs) of PtPd/CNWs catalysts almost keep constant after 5000 potential cycling, whereas 20% Pt/C drops almost 40% after 5000 potential cycling. Graphical abstract Image 1 Highlights • Synthesizing PtPd/CNWs catalysts by electrospinning is facile and scalable. • The PtPd/CNWs exist in the form of membrane, which can be directly applied as catalyst layer. • The C around PtPd NPs can prevent agglomeration and sintering of nanoparticles without affecting the active sites. • PtPd/CNWs catalysts have outstanding activity and stability than standard Pt/C catalysts. • The activity for ORR of binary catalysts is higher than that of ternary catalysts. [ABSTRACT FROM AUTHOR]

This paper presents a new zero voltage switching (ZVS) tuning method for the double-sided inductor/capacitor/capacitor (LCC) compensated wireless power transfer (WPT) system. An additional capacitor is added in the secondary side of the double-sided LCC compensation network in order to tune the network to realize ZVS operation for the primary-side switches. With the proposed tuning method, the turn off current of the primary-side switches at the low input voltage range can be reduced compared with the previous ZVS tuning method. Consequently, the efficiency of the WPT at the low input voltage range is improved. Moreover, the relationship between the input voltage and the output power is more linear than that of the previous ZVS tuning method. In addition, the proposed method has a lower start-up voltage. The analysis and validity of the proposed tuning method are verified by simulation and experimental results. A WPT system with up to 3.5 kW output power is built, and 95.9% overall peak efficiency is achieved. [ABSTRACT FROM AUTHOR]

Background: Understanding epidemiological characteristics of diabetes in a specific population will potentially benefit prevention and control of diabetes and policy-making. This study aimed to investigate the prevalence and awareness of diabetes, as well as its pharmacological, non-pharmacological and primary care management in Shenzhen, China.Methods: A cross-sectional study was conducted. We employed multistage cluster random sampling methods to select the participants. Face-to-face interview surveys were conducted to collect data. A total of 1676 participants completed the survey.Results: We found that the prevalence of diabetes was 4.8%. The prevalence of impaired fasting blood glucose was 6.0%. The prevalence rates of both diabetes and impaired fasting blood glucose increased with age (P < 0.001), whereas hypertension was strongly associated with diabetes only (odds ratio (OR) = 1.93, 95% confidence interval (CI) 1.15-3.22). The awareness of diabetes was poor (51.9%) and 54.3% of diabetic patients were not being treated pharmacologically. Less than one-third of diabetic patients were undergoing non-pharmacological treatments. Primary care management of diabetes was recorded for only 11.1% of the patients.Conclusions: Although diabetes prevalence in Shenzhen is about a half that of the Chinese average, high prevalence of impaired fasting blood glucose imposes a public health threat and burden to the health care system. Approximately half of the subjects with diabetes are undiagnosed. Our findings highlight the need of public health efforts for primary and secondary prevention, as well as early detection of diabetes. Primary care may be crucial an improved access to medical services and better management of diabetes. [ABSTRACT FROM AUTHOR]

Solar garden tractor not only drives tractor, but also does some garden works, and its driving system has unique requirement. A design method for driving system of solar garden tractor was put forward, which included the overall design and the main parameters of the theoretical calculation. Firstly, for the wheel drive mode's power transmission chain was short, and its driving and braking force distribution could be controlled and optimized by the energy management and power system, which was helpful to improve the drive system's efficiency, extend operation time and increase mileage, the wheel drive mode was therefore chosen as solar tractor drive system. Secondly, the components of solar tractor included the hub motor, the moving motor, the reducer, the battery pack and the photovoltaic panel. In order to evaluate solar tractor's working capacity, the cumulative operation time throughout day was proposed as the evaluation index. The cumulative operation time throughout day referred to the sum of solar tractor working time in a day after the battery was fully charged. According to the principle of solar tractor, i.e. obtained total energy is equal to consumed energy by the tractor, calculate the cumulative operation time throughout day. The obtained total energy by solar tractor was composed of photovoltaic panel output total energy throughout day and battery rated output energy. Based on a large number of test and analysis on solar radiation intensity and environment temperature on horizontal plane in Nanjing, solar radiation intensity model and environment temperature model were established under cloudless weather throughout the day to describe climate change. According to the parameters of photovoltaic panel, solar radiation intensity and environment temperature, the photovoltaic panel's P-V output characteristic curve was obtained, and based on the peak power of photovoltaic panel, total output energy values of 4 photovoltaic panels were calculated to be 2 976 and 1 536 W-h in summer and winter, respectively. Taking the design of solar garden tractor as an example, and combined with the Nanjing regional hourly meteorological variation, the daily generating capacity was predicted using photovoltaic panels in different seasons, and the relationships between the speed of tractor and accumulated operation time throughout day were calculated under the ramp transportation operation, ramp grass cutting operation, horizontal transportation operation and horizontal grass cutting operation working conditions. The results showed that, with the increase of operating speed, the trend of cumulative operation time throughout day was shortened, which was due to the decrease of the actual battery discharge capacity with the increase of discharge current. Under the same conditions, the cumulative operation time throughout the day in summer was longer than in winter. When the speed was 3 km/h, for tractor horizontal grass cutting operation with solar, the accumulated operation time throughout day was 14.5 h, and for without solar the time was 9.5 h. When the speed was 3 km/h, for tractor ramp grass cutting operation with solar, the accumulated operation time throughout day was 5.9 h, and under the same speed without solar, the accumulated operation time throughout day was 3.8 h. It was obvious that using photovoltaic panels greatly extended the tractor's accumulated operation time throughout day, which indicated that photovoltaic cell as garden tractor energy was feasible and also could meet the need of gardening works. The research results can be used for solar garden tractor driving system design and optimization, and provide the basis for the development of solar garden tractor. [ABSTRACT FROM AUTHOR]

The present study aimed to develop a heterogeneous catalysis process for diacylglycerols (DAG) production through low-temperature chemical glycerolysis. Of the heterogeneous catalysts evaluated, MgO-supported KOH (KOH-MgO) was found effective for the low-temperature chemical glycerolysis, and the KOH-MgO was characterized by FT-IR and powder XRD. Reaction temperature was of paramount importance and 80°C was found necessary to enhance the present reaction. Molar ratio of oil to glycerol at stoichiometric ratio (2:1) gave more DAG formation. 41.8 ± 0.8 wt% of DAG was obtained under these conditions: KOH-MgO concentration 4.5 wt% based on oil, acetone dosage 3:1 (acetone to oil in weight ratio), molar ratio of oil to glycerol 2:1, reaction temperature 80°C and time 12 h. Practical applications: Heterogeneous catalysis has been recognized as green process, it is advantageous over the homogeneous catalysis in terms of separation and reusability of catalysts. The MgO-supported KOH catalyst described in this study can effectively catalyze the low-temperature chemical glycerolysis, it could be considered for practical applications. [ABSTRACT FROM AUTHOR]

As catalytic active sites of nitrogen (N)-doped carbon nanomaterials (CNMs) for oxygen reduction reaction (ORR) are always under debate, synthesis of high purity pyridinic-N dominated CNMs is an effective approach to study the relation between pyridinic-N and active sites, as well as catalytic mechanism for ORR. Herein, the carbon nanofibers (CNFs) etched by hydrofluoric (HF) acid can be used to synthesize pure pyridinic-N, suggesting that the exposed edge-patterned surface facilitates to synthesize pure pyridinic-N. Moreover, it reveals that the carbon atoms adjacent to pyridinic-N could be the catalytic active sites for ORR. [ABSTRACT FROM AUTHOR]

Microbial fabrication is eco-friendly for nobel-metal catalysts typically used in proton exchange membrane fuel cell (PEMFC). In our study, nano-Pd electrocatalysts were successfully prepared by using three Shewanella s as precursors through hydrogen reduction (200 °C) and carbonization (800 °C). The analysis revealed that the catalysts showed outstanding ORR electrocatalytic performance via a predominant four-electron oxygen reduction pathway in alkaline medium. The best performance was obtained for Pd/HNC-32, which showed a mass activity at 0.526 A mg−1, 3.78 times higher than that of commercial Pd/C. Shewanella putrefaciens CN-32 was a more effective Pd-adsorbent. The enhanced performance can be ascribed to the small Pd-particle size and uniform dispersion on microbial support, which results from stronger hydrophilicity of Shewanella putrefaciens CN-32. The content of nitrogen is another key to the performance of Pd/HNC-32. This study developed a promising strategy for screening microbial strains for electrocatalyst fabrication. • Carboxyl is a key surface functional group, which determines the positive ability of Shewanella s to adsobing Pd2+. • Good wetting performances of cells would effectively avoid the agglomeration of Pd particles supported on Shewanella s. • Pd/HNC-32 has best catalytic performances due to smaller size of monodispersed Pd and high content of Pd and nitrogen. • CN-32 is optimal precursor of three Shewanella s for Pd electrocatalyst prepared via our convenient and environmental method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preparing fenofibrate sustained-release nanofibers by electrospinning. • Polyvinylpyrrolidone is beneficial to improve the release rate of fenofibrate. • Nanofiber membrane is a new sustained-release dosage form for FN. Fenofibrate is widely used as a lipid-lowering drug. However, fenofibrate has a short half-life, so it needs to be prepared as a sustained-release preparation to prolong the administration time. In this study, fenofibrate nanofibers are prepared by electrospinning using the biodegradable material polylactic acid as a drug carrier. To improve the hydrophilicity and cumulative drug release rate, polyvinylpyrrolidone is introduced to prepare a composite drug-loaded nanofibrous membrane. The experimental results show that the hydrophilicity and cumulative release rate are improved. This study provides a simple and efficient method for the preparation of fenofibrate nanofibrous membranes with sustained-release effects. [ABSTRACT FROM AUTHOR]

One-dimensional carbon nanofibers hold great promise to be potential candidates as high-efficiency electrocatalysts for oxygen reduction reaction (ORR). However, the catalysts in powder form always aggregate when preparing catalyst layer, which significantly hinders the extensive application. Herein, we report the facile synthesis of iron and nitrogen co-containing porous carbon nanofibers derived from PAN nanofibers existing as a flexible film via the electrospinning method, which could avoid aggregation when fabricating catalyst layer of fuel cells. The Fe–N/N–C NFs exhibit onset potential of 0.95 V and the half-wave potential of 0.78 V in 0.1 M KOH solution, suggesting superior electro-catalytic activity for ORR. Meantime, for Fe–N/N–C NFs catalyst, it shows a nearly four electron transferring process and the current density only decreases by 14.2% after 40,000 s. This easy and facile method provides a new idea for synthesis of oxygen reduction reaction with high-activity and good-stability. • A facile method of synthesizing iron and nitrogen co-containing nanofibers. • The concentration of the active sites Fe-Nx was increased via an easy method. • The Fe–N/N–C pNFs exhibit outstanding electrocatalytic activity for ORR. • Providing guidance for fabricating high-efficiency Fe–N–C catalysts for ORR. [ABSTRACT FROM AUTHOR]

Here we report a dramatically enhanced hydrogen evolution reaction (HER) catalyst by acid etched MoS 2 (A-MoS 2 ). For the etching and oxidation effects of HNO 3 , the active site and electrical transport are significantly improved by simply controlling of processing time. The A-MoS 2 exhibits promising electrocatalytic performance, including much smaller onset overpotential (∼80 mV), an overpotential of 210 mV at 10 mA/cm 2 , and a Tafel slope of 97 mV/dec (the pristine MoS 2 180 mV/dec). The enhanced HER performance of MoS 2 may be attributed to the increased edge S atoms and the charge induced by the O doping. [ABSTRACT FROM AUTHOR]