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In order to screen out the feeding ratio of high‐quality algae strains in Hyriopsis cumingii, this experiment investigated the effects of different ratio of mixed feeding of two algae strains (Scenedesmus dimorphus and Cyclotella sp.) on the growth, bead production performance, trace elements, and amino acid composition of the newborn shell of H. cumingii. The results showed that the mixed feeding of two types of microalgae with different densities had significant effects on the growth performance, bead production quality, trace elements, and amino acid composition of the newly formed shell of H. cumingii (p < 0.05); the best body weight gain rate and shell growth rate were obtained by feeding S. dimorphus (30 × 105 cell/mL) and Cyclopella sp.(8 × 105 cell/mL); the pearl weight gain rate, amino acid ratio, Ca2+ and Mn2+ content were best when feeding Cyclotella sp. (16 × 105 cell/mL), but there was no significant difference compared with S. dimorphus (30 × 105 cell/mL) and Cyclopella sp.(8 × 105 cell/mL). In summary, the optimal feeding amount for the intensive breeding process of H. cumingii is S. dimorphus (30 × 105 cell/mL) and Cyclopella sp. (8 × 105 cell/mL). [ABSTRACT FROM AUTHOR]

Bio-based copolymers with excellent mechanical properties and biodegradability are highly desired for packaging and agricultural applications. In this work, a series of high molecular weight bio-based poly(ester-carbonate)s are synthesized using glycolic acid (GA), dimethyl carbonate (DMC), and 1,4-butanediol (BDO). The intrinsic viscosity ([1]) of these copolymers ranges from 0.70 to 1.11 dL/g. The tensile strength, elastic modulus, and elongation at break of PBCGA10 are 19.69 ± 2.40 MPa, 151.20 ± 37.17 MPa, and 1173 ± 142%, respectively, which are superior to the mechanical properties of PBAT. The degradation weight loss of PBCGA10 and PBCGA20 after 30 days can reach 8% and 40%, respectively, indicating excellent degradation performance of the copolymers. Moreover, copolymers undergo degradation through a surface degradation mechanism. The main products of copolymer degradation are BDO, CO2, and H2O, which do not cause harm to organisms and the environment. [ABSTRACT FROM AUTHOR]

Harvest maturity significantly affects the quality of apple fruit in post-harvest storage process. Although the regulatory mechanisms underlying fruit ripening have been studied, the associated epigenetic modifications remain unclear. Thus, we compared the DNA methylation changes and the transcriptional responses of mature fruit (MF) and immature fruit (NF). There were significant correlations between DNA methylation and gene expression. Moreover, the sugar contents (sucrose, glucose, and fructose) were higher in MF than in NF, whereas the opposite pattern was detected for the starch content. The expression-level differences were due to DNA methylations and ultimately resulted in diverse fruit textures and ripeness. Furthermore, the higher ethylene, auxin, and abscisic acid levels in MF than in NF, which influenced the fruit texture and ripening, were associated with multiple differentially expressed genes in hormone synthesis, signaling, and response pathways (ACS, ACO, ZEP, NCED, and ABA2) that were regulated by DNA methylations. Multiple transcription factor genes involved in regulating fruit ripening and quality via changes in DNA methylation were identified, including MIKCC-type MADS-box genes and fruit ripening-related genes (NAP, SPL, WRKY, and NAC genes). These findings reflect the diversity in the epigenetic regulation of gene expression and may be relevant for elucidating the epigenetic regulatory mechanism underlying the ripening and quality of apple fruit with differing harvest maturity. [ABSTRACT FROM AUTHOR]

Background & Aims: Currently, there is a lack of effective tools for predicting the prognostic outcome of early-stage lung cancer after surgery. We aim to create a nomogram model to help clinicians assess the risk of postoperative recurrence or metastasis. Materials and Methods: This work obtained 16,459 NSCLC patients based on SEER database from 2010 to 2015. In addition, we also enrolled 385 NSCLC patients (2017/01-2019/06) into external validation cohort at Tianjin Medical University General Hospital. Univariable as well as multivariable Cox regression was carried out for identifying factors independently predicting OS. In addition, we built a nomogram by incorporating the above prognostic factors for the prediction of OS. Results: Tumor size was positively correlated with the risk of poor differentiation. Advanced age, male and adenocarcinoma patients were factors independently predicting poor prognosis. The risk of white race is higher, followed by Black race, Asians and Indians, which is consistent with previous study. Chemotherapy is negatively related to prognostic outcome in patients of Stage IA NSCLC and positively related to that in those of Stage IB NSCLC. Lymph node dissection can reduce the postoperative mortality of patients. AUCs of the nomograms for 1, 2, and 3-year OS was 0.705, 0.712, and 0.714 for training cohort, while those were 0.684, 0.688, and 0.688 for validation cohort. Conclusions: The nomogram could be used as a tool to predict the postoperative prognosis of patients with Stage I non-small cell lung cancer. [ABSTRACT FROM AUTHOR]

Aim: Drug-induced liver injury (DILI) poses significant challenges to clinical practice. Currently, there is no recommended therapy to treat DILI; therefore, it is vital to explore new therapeutic agents. This study aimed to investigate the efficacy and safety of silybin meglumine tablets in treating DILI. Methods: This study analysed 34 296 DILI cases assessed by the updated RUCAM from a nationwide database. A total of 301 patients with RUCAM scores ≥6 were directly enrolled in this study, while an additional 340 patients with RUCAM scores <6 who were adjudged as probable DILI by a panel of three hepatologists were also included in the analysis. The enrolled patients were divided into the silybin meglumine group and the control group. The propensity score matching (PSM) method was used to obtain comparable characteristics between the two groups. Results: There were 129 cases in the silybin meglumine group and 512 cases in the control group. After applying PSM, 129 matched pairs were obtained. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) resumption rates in the silybin meglumine group were significantly higher than the control group (58.91% vs. 20.93%, P ≤ .0001 and 63.49% vs. 37.50%, P ≤ .0001). The univariate and multivariate logistic regression analysis revealed that grouping factor (odds raio [OR], 5.42; 95% confidenxe interval [CI], 3.12–9.39; P < .0001 and OR, 6.10; 95% CI, 2.98– 12.48; P < .0001) and ALT levels (OR, 0.95; 95% CI, 0.93–0.98; P = .0015 and OR, 0.95; 95% CI, 0.92–0.99; P = .0157) were essential influencing factors for ALT normalization. Conclusions: Silybin meglumine tablets are safe and effective in DILI treatment. Large-scale and randomized controlled trials are required to further confirm their efficacy. [ABSTRACT FROM AUTHOR]

Performance prediction plays an important role in the predesign stage of centrifugal compressors. A set of loss models is usually selected and grouped to fulfill the above prediction. To improve the defects of traditional prediction, we modified the outlet velocity and slip coefficient of the impeller by means of the energy average method to obtain theoretical work. A new volute loss model is proposed to replace the traditional semiempirical loss model by adopting a suitable loss model for each flow passage component. A proper performance prediction method is established for the centrifugal compressor studied in this paper. The overall performance of a single‐stage centrifugal compressor is predicted and compared with experimental and numerical simulation results. It is found that the prediction method proposed can better predict the overall performance of the centrifugal compressor. And the volute loss is the third largest loss after impeller loss. [ABSTRACT FROM AUTHOR]

The thermal response test (TRT) in an aquifer establishes a relationship between the groundwater flow rate and the recorded temperature response curve of temporal ground heating. A major challenge for achieving a mature hydrogeological field test is to minimize borehole effects by smart practical solutions of in situ heating and temperature sensing. When borehole effects are substantial, concepts are needed to separate their contribution to the recorded signal. This is especially the case when heating and sensing devices are installed in grouted boreholes as permanent testing stations. Interpretation of a recorded response curve thus means solving a transient heat transfer problem with radial conduction through composite media. Here, a series of numerical models are set up to study the effect of the grout and the jacket of an actively heated fiber-optic cable on the simulated thermal response measured along a heated borehole. The findings are utilized to further develop existing groundwater flow rate estimation procedures based on the moving infinite line source model. The developed approach is demonstrated in a case study in a borehole near a bank collapse site that penetrates different aquifer layers. Accordingly, significant local groundwater flow rates (9 × 10 −7–5 × 10 −6 m·s −1) are found that vary with depth. The values derived by the TRT interpretation closely match the expected rates (2 × 10 −6–7 × 10 −6 m·s −1), which supports the good applicability of the estimation procedure in the field. [ABSTRACT FROM AUTHOR]

Microbial nitrogen (N) immobilization, which typically results in soil N retention but based on the balance of gross N immobilization over gross N production, affects the fate of the anthropogenic reactive N. However, global patterns and drivers of soil gross immobilization of ammonium (INH4) and nitrate (INO3) are still only tentatively known. Here, we provide a comprehensive analysis considering gross N production rates, soil properties, and climate and their interactions for a deeper understanding of the patterns and drivers of INH4 and INO3. By compiling and analyzing 1966 observations from 274 15N-labelled studies, we found a global average of INH4 and INO3 of 7.41 ± 0.72 and 2.03 ± 0.30 mg N kg-1 day-1 w ith a r atio of I NO3 to INH4 (INO3:INH4) of 0.79 ± 0.11. Soil INH4 and INO3 increased with increasing soil gross N mineralization (GNM) and nitrification (GN), microbial biomass, organic carbon, and total N and decreasing soil bulk density. Our analysis revealed that GNM and GN were the main stimulators for INH4 and INO3, respectively. The structural equation modeling showed that higher soil microbial biomass, total N, pH, and precipitation stimulate INH4 and INO3 through enhancing GNM and GN. However, higher temperature and soil bulk density suppress INH4 and INO3 by reducing microbial biomass and total N. Soil INH4 varied with terrestrial ecosystems, being greater in grasslands and forests, which have higher rates of GNM, than in croplands. The highest INO3:INH4 was observed in croplands, which had higher rates of GN. The global average of GN to INH4 was 2.86 ± 0.31, manifesting a high potential risk of N loss. We highlight that anthropogenic activities that influence soil properties and gross N production rates likely interact with future climate changes and land uses to affect soil N immobilization and, eventually, the fate of the anthropogenic reactive N. [ABSTRACT FROM AUTHOR]

Soil gross nitrification (GN) is a critical process in the global nitrogen (N) cycle that results in the formation of nitrate through microbial oxidation of ammonium or organic N, and can both increase N availability to plants and nitrous oxide emissions. Soil GN is thought to be mainly controlled by soil characteristics and the climate, but a comprehensive analysis taking into account the climate, soil characteristics, including microbial characteristics, and their interactions to better understand the direct and indirect controlling factors of GN rates globally is lacking. Using a global meta-analysis based on 901 observations from 330 15N-labeled studies, we show that GN differs significantly among ecosystem types, with the highest rates found in croplands, in association with higher pH which stimulates nitrifying bacteria activities. Autotrophic and heterotrophic nitrifications contribute 63% and 37%, respectively, to global GN. Soil GN increases significantly with soil total N, microbial biomass, and soil pH, but decreases significantly with soil carbon (C) to N ratio (C:N). Structural equation modeling suggested that GN is mainly controlled by C:N and soil total N. Microbial biomass and pH are also important factors controlling GN and their effects are similar. Precipitation and temperature affect GN by altering C:N and/or soil total N. Soil total N and temperature drive heterotrophic nitrification, whereas C:N and pH drive autotrophic nitrification. Moreover, GN is positively related to nitrous oxide and carbon dioxide emissions. This synthesis suggests that changes in soil C:N, soil total N, microbial population size, and/or soil pH due to anthropogenic activities may influence GN, which will affect nitrate accumulation and gaseous emissions of soils under global climate and land-use changes. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is one of the most common malignant tumours, with multiple driving factors and biological transitions involved in its development. Claudin-2 (CLDN2), a well-defined component of cellular tight junction, has been indicated to associate with CRC progression. However, the function of CLDN2 and the underlying mechanism whereby the downstream signalling transduction is regulated in CRC remains largely unclear. In this study, we demonstrated that CLDN2 is upregulated in CRC samples and associated with poor survival. And CLDN2 depletion significantly promotesN-myc downstreamregulated gene 1 (NDRG1) transcription, leading to termination of the CRC growth and metastasis in vitro and in vivo. Mechanistically, this process promotes CLDN2/ZO1/ZONAB complex dissociation and ZONAB shuttle into nucleus to enrich in the promoter of NDRG1. Thus, this study reveals a novel CLDN2/ZO1/ZONAB-NDRG1 axis in CRC by regulating the expression of EMTrelated genes and CDKIs, suggesting CLDN2 may serve as a promising target for CRC treatment. [ABSTRACT FROM AUTHOR]

Background: Growing evidence has proved that stromal cells, as the critical component of tumor microenvironment (TME), are closely associated with tumor's progression. However, the model based on stromal score to predict progression-free survival (PFS) in papillary thyroid carcinoma (PTC) has not been developed. The study aimed at exploring the relation between stromal score and prognosis, then establishing a nomogram to predict PFS of patients with PTC. Method: We obtained the stromal score and clinicopathological characteristics of PTC patients from The Cancer Genome Atlas (TCGA) database. Cox regression analysis assisted in selecting prognosis-related factors. A stromal score-based nomogram was built and verified in the training and validation cohorts, respectively. The calibration curve, concordance index (C-index), decision curve analysis (DCA) as well as receiver operating characteristic (ROC) curve assisted in measuring the performance exhibited by the nomogram. Results: We divided 381 PTC patients into the training cohort (n = 269) and the validation cohort (n = 112) randomly. Compared with patients who had a low stromal score, patients with a high stromal score appeared with significantly better PFS [Hazard ratio (HR) and 95% confidence interval (CI): 0.294, 0.130–0.664]. The Cindex of the PFS nomogram was 0.764 (0.662–0.866) in the training cohort and 0.717 (0.603–0.831) in the validation cohort. The calibration curves for PFS prediction in the nomogram were remarkably consistent with the actual observation. DCA indicated superior performance of the nomogram to predict PFS than the American Joint Committee on Cancer (AJCC) Tumor Node Metastasis (TNM) staging system. The ROC curves showed the favorable sensitivity and specificity of the novel nomogram. Conclusion: High stromal score was significantly associated with improved PFS in patients with PTC. The nomogram based on the stromal score and clinicopathological patterns yielded a reliable performance to predict the prognosis of PTC. [ABSTRACT FROM AUTHOR]

The electrochemical conversion of carbon dioxide (CO2) to carbon monoxide (CO) is a favorable approach to reduce CO2 emission while converting excess sustainable energy to important chemical feedstocks. At high current density (>100 mAcm-2), low energy efficiency (EE) and unaffordable cell cost limit the industrial application of conventional CO2 electrolyzers. Thus, a crucial and urgent task is to design a new type of CO2 electrolyzer that can work efficiently at high current density. Here we report a polymer-supported liquid layer (PSL) electrolyzer using polypropylene non-woven fabric as a separator between anode and cathode. Ag based cathode was fed with humid CO2 and potassium hydroxide was fed to earthabundant NiFe-based anode. In this configuration, the PSL provided high-pH condition for the cathode reaction and reduced the cell resistance, achieving a high full cell EE over 66% at 100 mAcm-2. [ABSTRACT FROM AUTHOR]

Gas‐insulated lines (GIL) are widely used due to their many advantages in power plants and substations. The security and reliability of GIL is achieved by continues testing and monitoring. The main fault in the GIL compartments is overheating, which is rarely to occur, nonetheless, it cannot be ignored. In the present study, GIL steady‐state thermal behavior was investigated. For this reason, a multiphysics finite element model (FEM) was built to analyze the magneto‐hydro‐thermal characteristics of the GIL insulation gas. The simulation coupling includes the electromagnetic field, flow field and thermal heat transfer field. SF6/N2 and CF3I/N2 mixtures were studied and the influence of different gas properties on the magnetic flux density, heat distribution and flow velocity had been investigated. The results were compared to an experimental setup to validate the model calculations. Temperature rise tests have been conducted on the GIL inner and outer shell. The measurements were in good agreement with the simulation results. Finally, the presented work is also to serve as a good reference in future design and optimization of GIL structure. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Traditional modeling and optimization methods for high voltage equipment, specially, circuit breaker components and nozzles, require manual testing and improvement of a large number of parameters, and the efficiency is relatively low. The strong processing power of artificial intelligence technology in the identification and prediction of complex systems is an effective solution in such case. This paper presents the optimization approach of image recognition combined with deep learning for circuit breaker nozzle. The nozzle model was conducted using the high Mach flow model in a commercial software (COMSOL Multiphysics 5.4) to study the gas flow state and behavior during cold flow, and obtains Shock wave image recognition model of the nozzle chamber based on the convolutional neural network (CNN) method of multiscale layered features. On the basis of effective image recognition, combined with deep learning Convolutional Recurrent Neural Network (CRNN), the image sequence under different parameters is sent to the convolutional layer for feature extraction, and then the feature map is input into the loop. The prediction sequence is obtained through the layer, and finally the relationship between the kinematic parameters of the nozzle and the internal gas flow state is predicted through the prediction layer. Results indicated, according to the prediction of CRNN, the range of the throat length should be between 7 and 13 mm and the angle should be between 8 ∼ 15°. The presented method could be also used for similar materials and components, with certain universality. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Existing models describing continental crust deformation require the coexistence of strike-slip faults and crustal blocks rotating between them, although the dimension and shape of the blocks and the location and offset of the faults are mostly unconstrained. Here we report on the paleomagnetism of middle Cenozoic (<45 Ma) continental red beds exposed along the 40 km long and 2-8 km wide NW-trending Mula basin (East Tibet), unconformably lying above Triassic marine strata and plutons and mildly deformed by two subparallel thrust faults. A tectonic magnetic fabric and magnetic lineations subhorizontal and parallel to the compressive fronts show that thrust tectonics guided basin formation and continued soon after sediment deposition. Characteristic and high-temperature components isolated at 17 sites support a positive fold test and suggest primary detrital magnetization acquisition. The comparison with East Asia paleopoles defines several 2-5 km wide crust fragments yielding variable rotations from ~30° counterclockwise to ~90° clockwise without clear rotation trend. No strike-slip fault with offset exceeding 1 km occurs among blocks, and no regional-scale strike-slip fault is documented at basin vicinity, implying that the East Tibet rotation pattern is different from all existing block rotation models. A regional high thermal flow and vigorous geothermal activity are consistent with the occurrence of a ductile crust layer identified by seismological data at 13-30 km depths. We suggest that midlower crust, flowing SE-ward toward Indochina, drag upper crust fragments that were randomly rotated depending on the local torque exerted on lower block boundaries by a ductile crust flow. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 into formic acid (HCOOH) is of particular interest as a hydrogen carrier and chemical feedstock. However, its conversion is limited by a high overpotential and low stability due to undesirable catalysts and electrode design. Herein, an integrated 3D bismuth oxide ultrathin nanosheets/carbon foam electrode is designed by a sponge effect and N-atom anchor for energy-efficient and selective electrocatalytic conversion of CO2 to HCOOH for the first time. Benefitting from the unique 3D array foam architecture for highly efficient mass transfer, and optimized exposed active sites, as confirmed by density functional theory calculations, the integrated electrode achieves high electrocatalytic performance, including superior partial current density and faradaic efficiency (up to 94.1%) at a moderate overpotential as well as a high energy conversion efficiency of 60.3% and long-term durability. [ABSTRACT FROM AUTHOR]

Low voltage distribution networks with the high penetration of photovoltaic (PV) units are facing four types of challenges, including over-voltage issues, under-voltage issues, voltage fluctuation issues and high power losses. In order to mitigate the above issues, this study proposes a multi-mode adaptive local reactive power control method based on Q(P) characteristics. A new concept, node virtual injection active power (NVIP), is developed to take the PV active power, load active power and load reactive power as a whole and as the basis to regulate the PV reactive power. Then, an NVIP-based multi-mode local Q(P) framework is proposed to consider the four types of challenges based on four operation modes, respectively, that can be adaptively switched according to the NVIP value and the NVIP variation. In addition, a systematic parameter design for the Q(P) framework is proposed based on an optimisation model to further enhance the effectiveness of the proposed multi-mode control. The simulation results demonstrate the effectiveness of the proposed method in mitigating voltage violations and voltage fluctuations, and improving the power losses and power factor. [ABSTRACT FROM AUTHOR]

The use of optical imaging and bipolar electrochemical arrays is a powerful approach for optically monitoring as well as spatially and temporally resolving heterogeneous electron-transfer processes. Previous studies, however, have been largely limited to the study of slower or steady-state redox processes. In this work, we use electrochemiluminescence (ECL) to demonstrate the ability to optically record transient collision events of single platinum nanoparticles on a carbon ultramicroelectrode (UME). The electrocatalytic signal of a Pt nanoparticle on a cathodic pole of a bipolar electrode is coupled to the ECL signal on the anodic pole generating a transient optical signal. Correlated amperometric (i-t) and ECL (count-t) traces are then compared to determine critical parameters which influence the accurate temporal resolution of these rapid events. Our results suggest that ECL can be an effective means for spatially and temporally resolving transient redox processes when used on arrays of closed bipolar electrodes. [ABSTRACT FROM AUTHOR]

In order to explore the simulation method of the contact force for the ring-shaped spring and provide the support for the design of high-voltage switchgear-rated current and mechanical operating power, the parametric equation was derived, based on NX software the three-dimensional model was built, considering the influence of contact, friction, and large deformation, the non-linear dynamic finite element simulation model for the process of assembling and operating was established, the stress, resistance force, and friction force at any moment were obtained by simulation, and the variation of resistance and friction force during contact insertion was analysed. The results show that during the mechanical operating process, the resistance force rapidly increased to the extreme value and then gradually decreased to a stable value of 238N, and the friction force quickly increased and then slowly rose to the steady value of 238N, which is consistent with the experience and proved the rationality of the simulation model. Finally, according to the Coulomb friction law, the contact force of the spring contact was calculated as 1190N. [ABSTRACT FROM AUTHOR]

A 2‐pole fully tunable bandpass filter (BPF) with only two varactors implemented is proposed in this paper. The ultra‐wide center frequency (CF) tuning range is built on short‐ended stepped‐impedance resonators (SIRs). Two varactors are placed at the symmetrical plane of the filter in series and shunt configurations, according to the odd‐even mode analysis the CF and bandwidth (BW) of the passband can be tuned independently without adding any redundant tuning elements. The CF of the proposed filter can be tuned from 0.61 to 2.39 GHz. The 3 dB BW tuning range is 150‐260 MHz at the lower side and 290‐520 MHz at the upper side of the entire passband tuning range. Good agreement is observed between simulated and measured results. [ABSTRACT FROM AUTHOR]

Mesenchymal stem/stromal cells (MSCs) provide an attractive cell source for cartilage repair and cell therapy; however, the underlying molecular pathways that drive chondrogenesis of these populations of adult stem cells remain poorly understood. We generated a rich data set of high-throughput RNA sequencing of human MSCs throughout chondrogenesis at 6 different time points. Our data consisted of 18 libraries with 3 individual donors as biologic replicates, with each library possessing a sequencing depth of 100 million reads. Computational analyses with differential gene expression, gene ontology, and weighted gene correlation network analysis identified dynamic changes in multiple biologic pathways and, most importantly, a chondrogenic gene subset, whose functional characterization promises to further harness the potential of MSCs for cartilage tissue engineering. Furthermore, we created a graphic user interface encyclopedia built with the goal of producing an open resource of transcriptomic regulation for additional data mining and pathway analysis of the process of MSC chondrogenesis. [ABSTRACT FROM AUTHOR]

Communication data in the communication network of the islanded micro-grid can be disturbed in many ways, such as data attack or packet loss. To improve the control effect on the voltages and frequencies obtained by droop control of distributed energy resources (DERs) facing communication data disturbance (CDD), a response hierarchical control strategy is proposed in this study. Based on the concept of the cyber physical system, the control structure is divided into two layers: the cyber layer and physical layer. In the cyber layer, firstly, the effect of the CDD on the micro-grid system is analysed and then, an event-triggered data compensation method combining the back-propagation neural network and extreme learning machine is proposed in this layer to solve the problem of the CDD. In the physical layer, firstly, the droop control is used as the primary control to control the voltages and frequencies of DERs and then, a novel virtual leader-following consensus control method considering time-delay is proposed in this layer. Also, it is used to complete the secondary control of the voltage and frequency obtained by primary control. In the end, the simulation results confirm the effectiveness of the proposed hierarchical control strategy under CDD. [ABSTRACT FROM AUTHOR]

This study proposes a new family of high-boost-quasi-Z-source inverters (qZSIs) with combined active switchedinductor boost network. The proposed inverter provides continuous input current and higher-boost voltage inversion capability, shares common ground between the input source and the inverter bridge, which would be applicable for the renewable energy system with low-voltage distributed dc sources. In comparison to the traditional high-boost non-coupled-inductor-type qZSIs, for the same total number of passive/active components used at the impedance network, the proposed topology has higher modulation index with improved output voltage waveform quality, and lower switching voltage stress across the power switches. To produce the same voltage boost factor with the same dc input, the proposed inverter uses smaller inductance values compared with the conventional topologies. Thus, the size and weight of the passive components in the proposed topology can be reduced. This study presents the operating principles, power loss analysis, simulation results and characteristic comparison with those of the traditional high-boost qZSIs. Finally, a laboratory prototype based on the TMS320F28335 digital signal processor with 60 V dc input and 110 Vrms ac output was constructed to verify the effectiveness of the proposed inverter. [ABSTRACT FROM AUTHOR]

A novel floating p-well carrier stored trench bipolar transistor with L-shaped shield gates (LSG-FP-CSTBT) is proposed in this Letter. The proposed device features combinatorial L-shaped shield gates with a thick oxide layer in the lower part of the trench. Numerical analysis results show that compared to the conventional FP-CSTBT, the shield effect provided by the LSGs not only improves the trade-off relationship between the on-state voltage drop (V CEON) and turn-off loss (EOFF), but also improves the trade-off relationship between the turn-on loss (EON) of the device and reverse recovery dVAK/dt of the antiparallel freewheeling diode. Therefore, improved device performance and reduced electromagnetic interference noise are obtained. [ABSTRACT FROM AUTHOR]

Efficient and selective dehydrogenation of hydrazine borane (HB), a novel hydrogen storage material with very high hydrogen content (HB, 15.4 wt%), is a key challenge for a fuel-cell-based hydrogen economy. However, even using the noble metal catalysts for HB decomposition, the activities are still far from satisfying, to say nothing of non-noble-metal-containing catalysts. In response, as a proof-of-concept experiment, herein, noble-metal-free NiFe- CeOx nanoparticles are successfully immobilized on an MIL-101 support without surfactant by a simple liquid impregnation method. Unexpectedly, the resultant Ni0.5Fe0.5-CeOx/MIL-101 catalyst shows good performance, including 100% H2 selectivity, 100% conversion, and record catalytic activity (351.3 h-1) for hydrogen generation at mild temperature, which is even better than most of the noble metal heterogeneous catalysts and might be attributed to the good dispersion and uniform particle size of the Ni0.5Fe0.5- CeOx nanoparticles due to steric restrictions effect of the MIL-101 support. Additionally, extending MIL-101 to some other important kinds of metal-organic framework (MOF) structures, the resultant NiFe-CeOx/MOF catalysts all show good catalytic activity toward HB decomposition, showing the universality of the MOF supported NiFe-CeOx catalysts. [ABSTRACT FROM AUTHOR]

Trypsin inhibitor (TI), an important antinutritional factor present in soybean [Glycine max (L.) Merr.] seeds, prevents animal protein digestibility. Accurately determining seed TI concentration is essential for screening soybean breeding lines to select genotypes with low TI. A colorimetric assay is widely used to measure TI activity in soybean seeds. This bioassay is time consuming, expensive, and has repeatability issues. This study developed a high-performance liquid chromatography (HPLC) method as a high-throughput, less expensive, and more reliable assay to quantify Kunitz trypsin inhibitor (KTI), the major TI, in soybean seeds. We extracted KTI using sodium acetate buffer, separated on a Poros R2/H perfusion column and detected at 220 nm. The HPLC method was compared with two popular enzymatic bioassays using 100 soybean lines. For the bioassays, TI was extracted using HCl or NaOH extractants and determined according to Kakade et al. (1974). The KTI from the HPLC method ranged from 0.52 to 12.15 mg g-1 with an average of 5.25 mg g-1 and a limit detection of 0.05 mg g-1. The recovery of KTI in spiked soybean samples was 82.33%. The KTI data from HPLC and both bioassays were strongly correlated (r = 0.82 and 0.80, p ≤ 0.0001). The CVs of KTI data (66.20% for HPLC, 18.84 and 32.55% for bioassays) suggest that the HPLC method is capable of detecting a wider range of KTI quantities and providing a better sensitivity for quantifying KTI in soybean seed samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: Two or more different epidermal growth factor receptor (EGFR) mutations can be detected within a single tumor sample, which represents complex mutations. However, the frequency and efficacy of tyrosine kinase inhibitor (TKI) treatments for patients harboring these mutations are unknown. METHODS: From January 2011 to January 2017, patients diagnosed with EGFR mutations were screened. The effectiveness of TKIs in patients with complex mutations was retrospectively analyzed. RESULTS: A total of 16,840 subjects were screened, and there were 5898 positive patients. One hundred eighty-seven patients (3.2% of all patients with EGFR mutations) had complex EGFR mutations, and 51 of the patients with advanced adenocarcinoma were treated with TKIs as a first-line treatment. The objective response rates for patients who had Del-19121L858R mutations (n 5 15), Del-19/21L858R1atypical mutations (n 5 16), double atypical mutations (n 5 8), and complex mutations with a primary drug-resistant pattern (n 5 12) were 75.0%, 60.0%, 71.0%, and 8.3%, respectively. The median progression-free survival times for the 4 groups were 18.2 months (95% confidence interval [CI], 10.6-25.9 months), 9.7 months (95% CI, 3.3-15.8 months), 9.6 months (95% CI, 3.3-19.0 months), and 1.4 months (95% CI, 0.4-2.3 months), respectively. CONCLUSIONS: These results from the largest sample size suggest that EGFRTKI therapy is effective in patients with Del-19121L858R mutations, Del-19/21L858R1atypical mutations, and double atypical mutations but is less effective in patients with a primary drug-resistant pattern. Patients with the Del-19121L858R mutations may, therefore, benefit more from treatment with first-generation TKIs. [ABSTRACT FROM AUTHOR]

Directional modulation (DM) has been developed based on narrowband antenna arrays, which can form the desired constellation values in the directions of interest while scrambling the values and simultaneously maintaining a magnitude response as low as possible in other directions. In this study, for the first time, the authors develop a multi-carrier based DM framework using antenna arrays, where simultaneous data transmission over multiple frequencies can be achieved, so that a much higher data rate can be obtained. In addition, such a framework allows possible frequency division based multi-user access to the system and also provides the flexibility of using different modulation schemes at different frequencies. Then, they study the antenna location optimisation problem for multi-carrier based DM using a compressive sensing based approach by employing the group sparsity concept. Examples are provided for both the design of weight coefficients and the optimisation of antenna locations. [ABSTRACT FROM AUTHOR]

In developed area, there is not only dense electric power grid, but also dense gas pipelines. In this situation, the DC current injected into the earth through the grounding electrodes of a high-voltage DC system would aggravate the corrosion and even destroy the protection devices of the pipelines. In this study, a numerical approach is put forward to simulate the potential distribution in gas pipeline, which is regarded as long grounding system with insulating coating on the grounding conductor. The main cathodic protection methods for the pipeline are also modelled. The approach is validated by the experiment on a reduced-scale model. With this approach, the effectiveness of the measures to reduce the electrode potential distribution along the pipelines is analysed. [ABSTRACT FROM AUTHOR]

In this study, the discrete-time model is used to analyse a constant on-time one-cycle controlled boost converter operating in continuous conduction mode. Then, it derives the critical boundary between continuous conduction mode and discontinuous conduction mode. In terms of Newton-Raphson methodology, the numerical solutions of fixed points are obtained. Thereafter, the stability of closed-loop boost converter is analysed based on its Jacobian matrix. It remarks that a couple of conjugate multipliers of Jacobian matrix of the system cross the unit circle gradually with constant on-time value increasing, while the step-up power stage moves from period-1 state into Neimark–Sacker bifurcation. Based on the stability analysis, an additional current loop is developed to improve the control for extending the stable region. Finally, simulation and experimental results well validate the theoretical analysis. [ABSTRACT FROM AUTHOR]

This is a study based on the assumption that the volatilization of Cr gives rise to the poor sinterability of LaCrO3. We have studied the effect of buried materials (none, Al2O3, La2O3, Cr2O3, LaCrO3) on the sinterability of LaCrO3 by conventional sintering in air. It was observed that the sinterability of LaCrO3 in air is largely enhanced by burying with La2O3 (with a linear shrinkage of 12.5% and a relative density of 86.90%). The energy dispersive spectroscopy (EDS) infers that there is a volatilization of Cr in sintering of LaCrO3 in air and the volatilization of Cr does affect the sinterability of LaCrO3. [ABSTRACT FROM AUTHOR]

Soybean [Glycine max (L.) Merr] is an important agronomic crop around the world, used largely for animal feed. However, ~75% of the phosphorus (P) in soybean grain is in the form of phytic acid (PA) or phytate, the cation salt form of PA, which cannot be digested by monogastric and agastric animals including swine, poultry, and aquacultural animals, leading to decreased field efficiency and environmental detriment due to P runoff. Soybean lines have been developed with a reduced PA content using mutant alleles of three genes involved in the PA pathway: either the combination of lpa1 and lpa2 or mips1. However, the relationship among these alleles was unknown. This study was conducted to explore the impact of these three mutant alleles on soybean agronomic, seed quality, and seed composition traits. A population consisting of 30 recombinant inbred lines developed from a cross between V03-5901 (mips1) × 04-05N32 (lpa1/lpa2) was planted along with the parents at two locations in Virginia in 2014 and 2015. The results showed that (i) an additive relationship existed among the three different mutant alleles, resulting in lower PA content as more low-PA (LPA) mutant alleles were added; (ii) the lines with lpa1 allele had the highest field emergence, and thus lpa1 may be a good trait with which to create a commercially viable LPA soybean cultivar; and (iii) the interaction between the mips1 and lpa2 alleles resulted in raffinose content significantly lower than with either allele on its own. The findings of this study provided breeders with references for developing LPA soybean cultivars combined with other desirable traits. [ABSTRACT FROM AUTHOR]

Background The aim of this study was to examine the sensitivity and specificity of pyuria-based diagnosis of urinary tract infection ( UTI) in urine collected by transurethral catheterization, and the reliability of diagnosis of pyuria in urine collected in a perineal bag. The gold standard for UTI diagnosis is significant colony counts of a single organism in urine obtained in a sterile manner. Methods We enrolled 301 patients who underwent medical examination at the present hospital for possible UTI between January 2005 and December 2009. We collected 438 urine samples by transurethral catheterization. We investigated the accuracy of pyuria-based diagnosis of UTI using transurethral catheterization urine specimens, and the reliability of diagnosis of pyuria using bag-collected urine specimens. Results The false-negative rate of UTI diagnosis based on pyuria in transurethral catheterization urine sediments was 9.0%; there was no significant difference in the false-negative rate of UTI diagnosis between boys and girls. Approximately 28% of pyuria-positive bag-collected urine specimens were pyuria negative on transurethral catheterization; this rate was significantly higher in girls than in boys (56.7% vs. 8.9%, P < 0.0001). Conclusions The absence of pyuria in transurethral catheterization urine sediments does not rule out UTI. Pyuria in bag-collected urine specimens frequently consists of urine leukocytes from external genitalia as well as from the urinary tract. [ABSTRACT FROM AUTHOR]

Action recognition is one of the hottest research topics in computer vision. Recent methods represent actions based on global or local video features. These approaches, however, lack semantic structure and may not provide a deep insight into the essence of an action. In this work, the authors argue that semantic clues, such as joint positions and part-level motion clustering, help verify actions. To this end, a meta-action descriptor for action recognition in RGBD video is proposed in this study. Specifically, two discrimination-based strategies - dynamic and discriminative part clustering - are introduced to improve accuracy. Experiments conducted on the MSR Action 3D dataset show that the proposed method significantly outperforms the methods without joint position semantic. [ABSTRACT FROM AUTHOR]

Whether bis(2-(2′-benzo[4,5-α]thienyl)pyridinato-N,C3′)iridium(acetylacetonate) (btp2Ir(acac)) emission comes from carrier trapping and/or energy transfer, when doped in the 4,4′-bis(N-carbazolyl)biphenyl (CBP) host in organic light-emitting devices, is not clear; therefore, the btp2Ir(acac) emission in CBP hosts was studied. In the red-doped device, both N,N′-bis(1-naphthyl)-N,N′-diphenyl-1.1′-bipheny1-4-4′-diamine (NPB) and (1,1′-biphenyl-4′-oxy)bis(8-hydroxy-2-methylquinolinato)-aluminum (BAlq) emission appeared, which illustrated that CBP excitons cannot be formed at two emissive layer (EML) interfaces in the device. In the co-doped devices, NPB and BAlq emissions disappear and 1,4-bis[2-(3-N-ethylcarbazoryl)vinyl]benzene (BCzVB) emission appears, illustrating the formation of CBP excitons at two EML interfaces in these devices. The reason for this difference was analyzed and it was found that holes in the NPB layer could be made directly into the CBP host in the EML interface of the red-doped device. In contrast, holes were injected into CBP host via the btp2Ir(acac)/BCzVB dopants in the co-doped devices, which facilitated hole injection from the NPB layer to the EML, leading to the formation of CBP excitons at two EML interfaces in the co-doped devices. Therefore, btp2Ir(acac) emission was caused by carrier trapping in the red-doped device, while, in the co-doped devices, it resulted from both carrier trapping and energy transfer from the CBP. Furthermore, it was revealed that the carrier trapping mechanism is less efficient than the energy transfer mechanism for btp2Ir(acac) excitation in co-doped devices. In summary, our results clarified the excitation mechanism of btp2Ir(acac) in the CBP host. [ABSTRACT FROM AUTHOR]

Directional modulation (DM) can be achieved based on uniform linear arrays where the maximum spacing between adjacent antennas is half-wavelength of the frequency of interest in order to avoid spatial aliasing. To exploit the additional degrees of freedom provided in the spatial domain, sparse antenna arrays can be employed for more effective DM. In this study, the spare array design problem in the context of DM is formulated from the viewpoint of compressive sensing (CS), so that it can be solved using standard convex optimisation toolboxes in the CS area. In detail, a common set of active antennas needs to be found for all modulation symbols generating a response close to the desired one. The key to the solution is to realise that group sparsity has to be employed, as a common antenna set cannot be guaranteed if the antenna locations are optimised for each modulation symbol individually. Moreover, two practical scenarios are considered for the proposed design: robust design with model errors and design with practical non-zero-sized antennas, and corresponding solutions are found by modifying the proposed standard solution. [ABSTRACT FROM AUTHOR]

A micronano structure superhydrophobic film was fabricated on copper substrate by electrodeposition of chrome oxide layer and surface modification of stearic acid. The fabricated film shows high water contact angle (165.4°) and low sliding angle (1.8°), and also performs well at corrosion resistance (protection efficiency, 99.9989%). The surface was characterised by scanning microscope, X-ray photoelectron spectroscope and atomic force microscope. [ABSTRACT FROM AUTHOR]

Exponential consensus of non-linear stochastic multi-agent systems is investigated. The authors consider a class of non-linear stochastic multi-agent systems that are subject to time-varying delays, randomly occurring uncertainties and randomly occurring non-linearities. Impulsive pinning control algorithms are proposed to ensure that follower agents track the leader under a fixed topology. On the basis of the Lyapunov function and the Halanay differential inequality of impulsive dynamical systems, we derive sufficient conditions for the globally exponential consensus of the multi-agent systems. Finally, numerical simulations demonstrate the effectiveness of the proposed theoretical results. [ABSTRACT FROM AUTHOR]

The Eu2+-induced enhancement of defect luminescence of ZnS was studied in this work. While photoluminescence (PL) spectra exhibited 460 nm and 520 nm emissions in both ZnS and ZnS:Eu nanophosphors, different excitation characteristics were shown in their photoluminescence excitation (PLE) spectra. In ZnS nanophosphors, there was no excitation signal in the PLE spectra at the excitation wavelength λex > 337 nm (the bandgap energy 3.68 eV of ZnS); while in ZnS:Eu nanophosphors, two excitation bands appeared that were centered at 365 nm and 410 nm. Compared with ZnS nanophosphors, the 520 nm emission in the PL spectra was relatively enhanced in ZnS:Eu nanophosphors and, furthermore, in ZnS:Eu nanophosphors the 460 nm and 520 nm emissions increased more than 10 times in intensity. The reasons for these differences were analyzed. It is believed that the absorption of Eu2+ intra-ion transition and subsequent energy transfer to sulfur vacancy, led to the relative enhancement of the 520 nm emission in ZnS:Eu nanophosphors. In addition, more importantly, Eu2+ acceptor-bound excitons are formed in ZnS:Eu nanophosphors and their excited levels serve as the intermediate state of electronic relaxation, which decreases non-radiative electronic relaxation and thus increases the intensity of the 460 nm and 520 nm emission dramatically. In summary, the results in this work indicate a new mechanism for the enhancement of defect luminescence of ZnS in Eu2+-doped ZnS nanophosphors. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate the possibility of boosting action recognition performance by exploiting the associated scene context. Towards this end, the authors model a scene as a mid-level 'middle layer' in order to bridge action descriptors and action categories. This is achieved via a scene topic model, in which hybrid visual descriptors, including spatial- temporal action features and scene descriptors, are first extracted from a video sequence. Then, the authors learn a joint probability distribution between scene and action using a naive Bayes nearest neighbour algorithm, which is adopted to jointly infer the action categories online by combining off-the-shelf action recognition algorithms. The authors demonstrate the advantages of their approach by comparing it with state-of-the-art approaches using several action recognition benchmarks. [ABSTRACT FROM AUTHOR]

Much effort has been made to build appropriate models for a boost converter. However, these models were described as inexact or complicated expressions in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM). This study proposes a new modelling method based on propositional calculus and linear constraint. First, the equivalent operating conditions (OCs) of the boost converter in CCM and DCM are formulated. Second, according to the equivalent translation principle, the OCs of the boost converter in three different modes can be transformed into two linear inequalities. Moreover then, a unified model of the boost converter in CCM and DCM is obtained. Compared with mixed logical dynamical model, the proposed model (PM) of the boost converter is more concise. In addition, the PM is a large-signal model in the theoretical analysis. Finally, the model is simulated in MATLAB under different load conditions and its effectiveness is well verified by simulation results. Moreover, the experimental results are consistent with the simulation results. [ABSTRACT FROM AUTHOR]