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In this study, sea surface wind speed was retrieved using the Global Precipitation Measurement (GPM) dual-frequency precipitation radar (DPR) Ka-band data. In order to establish the Ka-band model at low incidence angles, the dependence of the DPR Ka-band normalized radar cross section (NRCS) on the wind speed, incidence angle, sea surface temperature (SST), significant wave height (SWH), and sea surface current speed (CSPD) was analyzed first. We confirmed that the normalized radar cross section depends on the wind speed, incidence angle, and SST. Second, an empirical model at low incidence angles was established. This model links the Ka-band NRCS to the incidence angle, wind speed, and SST. Additionally, the wind speed was retrieved by the model and was validated via the GPM Microwave Imager (GMI) wind product. The validation yielded a root mean square error (RMSE) of 1.45 m/s and the RMSE was better at a lower incidence angle and a higher SST. This model may expand the use of GPM DPR data in enriching the sea surface wind speed data set. It is also helpful for other Ka-band spaceborne radars at low incidence angles to measure wind speed in the future. [ABSTRACT FROM AUTHOR]

In terms of the instability of the full-order observer for the induction motor in the low-speed regenerative mode, the low-speed unstable region which leads to the extension of the commissioning cycle cannot be eliminated by the traditional adaptive law which aims at good system performance. It is proposed that the feedback gain matrix can control both the unstable region and the system performance both. To make a trade-off between the stability and performance by designing the feedback gain matrix is still an open problem. To solve this problem, first we analyze the cause of instability and derive constraints to ensure system stability by establishing a transfer function of the adaptive observing system for the speed. Then, with the derived constraints as the design criteria for the feedback gain matrix, a control strategy combining the weighted adaptive law with the improved feedback gain matrix is proposed to improve the stability at low speed. Finally, by comparing the traditional control strategy with the proposed control strategy through simulations and experiments, we show that the proposed control strategy achieves better performance with higher stability. [ABSTRACT FROM AUTHOR]

In terms of the instability of the full-order observer for the induction motor in the low-speed regenerative mode, the low-speed unstable region which leads to the extension of the commissioning cycle cannot be eliminated by the traditional adaptive law which aims at good system performance. It is proposed that the feedback gain matrix can control both the unstable region and the system performance both. To make a trade-off between the stability and performance by designing the feedback gain matrix is still an open problem. To solve this problem, first we analyze the cause of instability and derive constraints to ensure system stability by establishing a transfer function of the adaptive observing system for the speed. Then, with the derived constraints as the design criteria for the feedback gain matrix, a control strategy combining the weighted adaptive law with the improved feedback gain matrix is proposed to improve the stability at low speed. Finally, by comparing the traditional control strategy with the proposed control strategy through simulations and experiments, we show that the proposed control strategy achieves better performance with higher stability. [ABSTRACT FROM AUTHOR]

Background. Herbal formula Gegen-Qinlian Decoction (GQD) has been widely used in China for the treatment of type 2 diabetes mellitus (T2DM), but its efficacy and safety are unclear. Method. The studies were identified from the PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure database, Wanfang database, and VIP database using the keywords "Gegenqinlian" or "Gegen-Qinlian" or "Gegen-Qin-Lian" or "Ge Gen Qin Lian." Relevant studies were selected according to predefined inclusion and exclusion criteria. Study selection, data extraction, and validation were carried out by, at least, two reviewers with disagreements being settled by discussion. Results. After literature search, a total of 26 randomized controlled trials were included with a total of 2553 patients. There was evidence that compared with metformin, the combination of GQD and metformin significantly reduced the fasting plasma glucose levels (MD −1.79, 95% CI (−2.31, −1.27), p < 0.00001); 2-hour postprandial plasma glucose levels (MD −1.72, 95% CI (−2.12, −1.31), p < 0.00001); and glycosylated hemoglobin levels (MD −1.26, 95% CI (−1.80, −0.72), p < 0.00001), and no serious side effects were identified. Conclusion. These data suggest that GQD may be an effective herbal formula in treating T2DM without serious side effects. The addition of GQD also enhances the hypoglycemic effects of metformin. However, the evidence remains weak due to methodological flaws, which may amplify the therapeutic benefit of GQD. [ABSTRACT FROM AUTHOR]

At present, the industrial production of boron carbide requires high energy consumption and time-consuming. Herein, a "field-assisted synthesis" method was developed for the rapid synthesis of boron carbide nanopowders using boric acid and nano-carbon black as raw materials by applying a current size of 2 A directly through the mixed powders at 1600 °C and held it for 5 min. The phase composition and morphology of the product were characterized by XRD, SEM, EDS, and TEM. The results showed that the participation of current resulted in almost complete reaction of the raw material at 1600 °C, and nanoscale boron carbide was generated due to rapid nucleation at high temperatures. This work can provide important reference for the subsequent preparation of nano boron carbide and further expand the development field of boron carbide. [ABSTRACT FROM AUTHOR]

Background: For patients with steroid-refractory acute graft-versus-host disease (SR-aGVHD), effective second-line regimens are urgently needed. Mesenchymal stromal cells (MSCs) have been used as salvage regimens for SR-aGVHD in the past. However, clinical trials and an overall understanding of the molecular mechanisms of MSCs combined with basiliximab for SR-aGVHD are limited, especially in haploidentical haemopoietic stem cell transplantation (HID HSCT). Methods: The primary endpoint of this multicentre, randomized, controlled trial was the 4-week complete response (CR) rate of SR-aGVHD. A total of 130 patients with SR-aGVHD were assigned in a 1:1 randomization schedule to the MSC group (receiving basiliximab plus MSCs) or control group (receiving basiliximab alone) (NCT04738981). Results: Most enrolled patients (96.2%) received HID HSCT. The 4-week CR rate of SR-aGVHD in the MSC group was obviously better than that in the control group (83.1% vs. 55.4%, P = 0.001). However, for the overall response rates at week 4, the two groups were comparable. More patients in the control group used ≥ 6 doses of basiliximab (4.6% vs. 20%, P = 0.008). We collected blood samples from 19 consecutive patients and evaluated MSC-derived immunosuppressive cytokines, including HO1, GAL1, GAL9, TNFIA6, PGE2, PDL1, TGF-β and HGF. Compared to the levels before MSC infusion, the HO1 (P = 0.0072) and TGF-β (P = 0.0243) levels increased significantly 1 day after MSC infusion. At 7 days after MSC infusion, the levels of HO1, GAL1, TNFIA6 and TGF-β tended to increase; however, the differences were not statistically significant. Although the 52-week cumulative incidence of cGVHD in the MSC group was comparable to that in the control group, fewer patients in the MSC group developed cGVHD involving ≥3 organs (14.3% vs. 43.6%, P = 0.006). MSCs were well tolerated, no infusion-related adverse events (AEs) occurred and other AEs were also comparable between the two groups. However, patients with malignant haematological diseases in the MSC group had a higher 52-week disease-free survival rate than those in the control group (84.8% vs. 65.9%, P = 0.031). Conclusions: For SR-aGVHD after allo-HSCT, especially HID HSCT, the combination of MSCs and basiliximab as the second-line therapy led to significantly better 4-week CR rates than basiliximab alone. The addition of MSCs not only did not increase toxicity but also provided a survival benefit. [ABSTRACT FROM AUTHOR]

This paper assesses different retrieval schemes used for the Chinese Gaofen-3 Synthetic Aperture Radar (GF-3 SAR) co-polarized data. The data consist of 4186 GF-3 data points and collocated wind information from sources including the ASCAT scatterometer, HY2A-SCAT scatterometer, and National Data Buoy Center (NDBC) buoy wind data set. The VV-polarized geophysical model function (GMF) is a CMOD7 model while the HH-polarized GMF is a hybrid of the CMOD7 and PR model. Assessments involve comparisons between SAR-derived and collocated winds in terms of the root-mean-square difference (RMSD) and bias. First, a comparison between the two retrieval schemes for the VV-polarized data clearly shows that the optimal scheme performs better than the classical scheme for wind speed retrieval. Comparisons for HH-polarized data show similar results. These experiments indicate that the wind speed RMSDs for the GF-3 co-polarized data are within 2 m/s when using the optimal scheme. Moreover, the wind direction RMSDs from the two schemes have no significant difference, with values near 20°. Overall, these assessments indicate that the GF-3 co-polarized data are sufficient for operational wind speed retrieval using the optimal scheme. However, wind direction retrieval requires further improvement. [ABSTRACT FROM AUTHOR]

Abstract Fe 3 O 4 @C nano-adsorption was prepared by a simple one-step solvothermal synthesis method using Fe (NO 3) 3 、cyclodextrin as raw materials, meanwhile urea as an alkali source. The obtained samples were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, scanning electron microscopy, and Brunauer-Emmett-Teller. The adsorption behavior of the Fe 3 O 4 @C toward Cr (VI) and Congo red was also studied. The core-shell structure Fe 3 O 4 @C exhibited large specific surface area of 112.91 m2 g−1. The prepared Fe 3 O 4 @C samples demonstrated typical ferromagnetic behavior and high removal capacity in removing the toxic Cr (VI) ions and organic pollutant CR from wastewater, together with facile magnetic separability and good recyclability. Equilibrium adsorption performance was conducted by using the Langmuir and Freundlich model and Freundlich model could simulate the adsorption process of Congo red and Cr (VI) better. The maximum adsorption capacity of Cr (VI) and Congo red was 33.35 mg g−1 and 262.72 mg g−1 by calculation. [ABSTRACT FROM AUTHOR]

The first stage of field experiments involving the design and construction of a low-power consumption ocean bottom electro-magnetometer (OBEM) has been completed. To improve the performance of the OBEM, we rigorously evaluated each of its units, e.g., the data loggers, acoustic parts, internal wirings, and magnetic and electric sensors, to eliminate unwanted events such as unrecovered or incomplete data. The evaluations of the procedure included the following. Data logger: digitizer sensitivity, linearity, and errors Acoustic transceiver: "ENABLE," "DISABLE," "RANGE," "RELEASE1," "RELEASE2," and "OPTION1" functions Magnetic sensor: sensitivity of the fluxgate and orthogonality Electrical receiver: potential voltage, impedance, and frequency responses Power consumption: the maximum operating current of two sets of batteries Deployment and recovery procedures on deck We confirmed the optimal performance of the OBEM after repeatedly testing the procedures. The first offshore deployment of the OBEM together with ocean bottom seismographs (OBSs) was performed in NE Taiwan, where the water depth is approximately 1,400 m. The total intensity of the magnetic field (TMF) measured by the OBEM varied in the range of 44,100-44,150 nT, which corresponded to the proton magnetometer measurements. The daily variations of the magnetic field were recorded using the two horizontal components of the OBEM magnetic sensor. We found that the inclinations and magnetic data of the OBEM varied with two observed earthquakes when compared to the OBS data. The potential fields of the OBEM were slightly, but not obviously, affected by the earthquakes. [ABSTRACT FROM AUTHOR]

With the purpose to increase the threshold voltage of the enhancementmode GaN high-electronmobility transistors, we fabricated devices with gate field plates on the p-GaN/AlGaN/GaN/AlGaN double heterostructures. We observed an existence of a subthreshold region from the current--voltage transfer curves. The threshold voltage of the device extractedbasedon linear extrapolationmethod is much higher than that of a typical device without a gate field plate. We investigated electrical properties based on carrier distributions with the influence of gate electric field at different channel regions. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to investigate the correlation between triglyceride-glucose (TyG) index and cervical vascular function parameters in the general population without cerebrovascular disease. Materials and Methods: This was a cross-sectional study that recruited a total of 1996 participants without cerebrovascular disease. TyG index was calculated based on fasting triglycerides and glucose. All patients were divided into two groups based on the median TyG index: the high TyG group and the low TyG group. The differences in basic clinical characteristics and neck vascular function parameters between the two groups of participants were compared, and then the correlation between TyG index and neck vascular function parameters was investigated. Results: Participants with a high TyG index had lower systolic, diastolic, and mean flow velocities in the basilar, vertebral, and internal carotid arteries compared with those with a low TyG index. Participants with a high TyG index had higher pulsatility index in the left vertebral artery and right internal carotid artery, but this difference was not observed in the basilar artery. In addition, TyG index was significantly negatively correlated with systolic, diastolic, and mean flow velocities in the basilar, vertebral, and internal carotid arteries, and the correlation remained after adjusting for confounding factors. Conclusion: In the general population, there was a well-defined correlation between TyG index and cervical vascular function parameters, and increased TyG index was independently associated with reduced cervical vascular blood flow velocity. [ABSTRACT FROM AUTHOR]

Accumulated evidence indicates that autophagy is a response of cancer cells to various anti-cancer therapies. Autophagy is designated as programmed cell death type II, and is characterized by the formation of autophagic vacuoles in the cytoplasm. Numerous herbs, including Chinese herbs, have been applied to cancer treatments as complementary and alternative medicines, supplements, or nutraceuticals to dampen the side or adverse effects of chemotherapy drugs. Moreover, the tumor suppressive actions of herbs and natural products induced autophagy that may lead to cell senescence, increase apoptosis-independent cell death or complement apoptotic processes. Hereby, the underlying mechanisms of natural autophagy inducers are cautiously reviewed in this article. Additionally, three natural compounds--curcumin, 16-hydroxycleroda-3,13-dien-15,16-olide, and prodigiosin--are presented as candidates for autophagy inducers that can trigger cell death in a supplement or alternative medicine for cancer therapy. Despite recent advancements in therapeutic drugs or agents of natural products in several cancers, it warrants further investigation in preclinical and clinical studies. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this meta-analysis was to evaluate the predictive value of cervical lymph node metastasis through sentinel lymph node biopsy (SLNB) in patients with oral cancer.Materials and Methods: Two authors independently searched the databases of PubMed, Cochrane central register of controlled trials, EMBASE, and CNKI to find the potential suitable diagnostic study related to SLNB. The diagnostic sensitivity, specificity, positive likely hood ratio (+LR), negative likely hood ratio (-LR), diagnostic odds ratio (DOR) were pooled by Meta-DiSc1.4 software. The publication bias was assessed by funnel plot and line regression test.Results: After electronic searching the related databases, we finally included twenty diagnostic studies. The pooled sensitivity, specificity, +LR, and DOR were 0.91 (95% confidence interval [CI]: 0.88-0.94), 1.00 (95% CI: 0.99-1.00), 35.52 (95% CI: 19.19-65.75), and 323.50 (95% CI: 148.27-705.83), respectively, with fixed-effect model. Moreover, the pooled -LR was 0.13 (95% CI: 0.07-0.23) by random-effect model. The area under the summary receiver operating characteristic curve of SLNB for cervical lymph node metastasis was 0.99.Conclusion: SLNB had very high sensitivity and specificity for productizing cervical lymph node metastasis in oral cancer patients. [ABSTRACT FROM AUTHOR]

Collapse of the microvascular system is a prerequisite for radiation‐induced bone loss. Since type H vessels, a specific bone vessel subtype surrounded by platelet‐derived growth factor receptor β+ (PDGFRβ+) perivascular cells (PVCs), has been recently identified to couple angiogenesis and osteogenesis, we hypothesize that type H vessel injury initiates PDGFRβ+ PVC dysfunction, which contributes to the abnormal angiogenesis and osteogenesis after irradiation. In this study, we found that radiation led to the decrease of both type H endothelial cell (EC) and PDGFRβ+ PVC numbers. Remarkably, results from lineage tracing showed that PDGFRβ+ PVCs detached from microvessels and converted the lineage commitment from osteoblasts to adipocytes, leading to vascular injury and bone loss after irradiation. These phenotype transitions above were further verified to be associated with the decrease in hypoxia‐inducible factor‐1α (HIF‐1α)/PDGF‐BB/PDGFRβ signalling between type H ECs and PDGFRβ+ PVCs. Pharmacological blockade of HIF‐1α/PDGF‐BB/PDGFRβ signalling induced a phenotype similar to radiation‐induced bone damage, while the rescue of this signalling significantly alleviated radiation‐induced bone injury. Our findings show that the decrease in HIF‐1α/PDGF‐BB/PDGFRβ signalling between type H ECs and PDGFRβ+ PVCs after irradiation affects the homeostasis of EC‐PVC coupling and plays a part in vascular damage and bone loss, which has broad implications for effective translational therapies. [ABSTRACT FROM AUTHOR]

Background and Purpose: Paracetamol (acetaminophen) is the most widely used over-the-counter analgesic and overdosing with paracetamol is the leading cause of hospital admission for acute liver failure. 5-Lipoxygenase (5-LO) catalyses arachidonic acid to form LTs, which lead to inflammation and oxidative stress. In this study, we examined whether deletion or pharmacological inhibition of 5-LO could protect mice against paracetamol-induced hepatic toxicity.Experimental Approach: Both genetic deletion and pharmacological inhibition of 5-LO in C57BL/6J mice were used to study the role of this enzyme in paracetamol induced liver toxicity. Serum and tissue biochemistry, H&E staining, and real-time PCR were used to assess liver toxicity.Key Results: Deletion or pharmacological inhibition of 5-LO in mice markedly ameliorated paracetamol-induced hepatic injury, as shown by decreased serum alanine transaminase and aspartate aminotransferase levels and hepatic centrilobular necrosis. The hepatoprotective effect of 5-LO inhibition was associated with induction of the antitoxic phase II conjugating enzyme, sulfotransferase2a1, suppression of the pro-toxic phase I CYP3A11 and reduction of the hepatic transporter MRP3. In 5-LO(-/-) mice, levels of GSH were increased, and oxidative stress decreased. In addition, PPAR α, a nuclear receptor that confers resistance to paracetamol toxicity, was activated in 5-LO(-/-) mice.Conclusions and Implications: The activity of 5-LO may play a critical role in paracetamol-induced hepatic toxicity by regulating paracetamol metabolism and oxidative stress. [ABSTRACT FROM AUTHOR]

• Forty-eight Populus chitinases were identified and classified into seven groups. • The Populus chitinase gene family expanded primarily through tandem duplication. • The Populus and Arabidopsis chitinase families have undergone different expansion. • The expression of the Populus chitinase gene family is divergent and inducible. Chitinases, the chitin-degrading enzymes, have been shown to play important role in defense against the chitin-containing fungal pathogens. In this study, we identified 48 chitinase-coding genes from the woody model plant Populus trichocarpa. Based on phylogenetic analysis, the Populus chitinases were classified into seven groups. Different gene structures and protein domain architectures were found among the seven Populus chitinase groups. Selection pressure analysis indicated that all the seven groups are under purifying selection. Phylogenetic analysis combined with chromosome location analysis showed that Populus chitinase gene family mainly expanded through tandem duplication. The Populus chitinase gene family underwent marked expression divergence and is inducibly expressed in response to treatments, such as chitosan, chitin, salicylic acid and methyl jasmonate. Protein enzymatic activity analysis showed that Populus chitinases had activity towards both chitin and chitosan. By integrating sequence characteristic, phylogenetic, selection pressure, gene expression and protein activity analysis, this study shed light on the evolution and function of chitinase family in poplar. [ABSTRACT FROM AUTHOR]

Highlights: [•] Al(OH)3/(PAA-CO-PAM) sub-microspheres with three-dimensional interpenetrating network structure were synthesized. [•] The maximum adsorption capacity was 106.2mg/g within 150min. [•] Adsorption behavior for Pb(II) onto sub-microspheres belongs to the pseudo-second-order kinetic model. [•] Thermodynamic parameters indicated the adsorption process was spontaneous, endothermic and feasible. [Copyright &y& Elsevier]

We performed a prospective study to evaluate the efficacy and safety of secondary antifungal prophylaxis (SAP) for patients with a history of invasive pulmonary aspergillosis (IPA) in allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this study, the prophylactic agents used were chosen based on treatment response to initial antifungal therapy. One hundred and thirty-six patients undergoing allo-HSCT with prior IPA were enrolled in this multicenter study. The agents of SAP included itraconazole in 24, voriconazole in 74, caspofungin in 32, and liposomal amphotericin B in 6. Eighty-eight patients had stable IPA and 48 had active IPA at the time of transplantation. The success rate of SAP was 91.2%. Twelve patients developed breakthrough invasive fungal disease (IFD), and none discontinued antifungal agents because drug-related adverse events. The incidence of breakthrough IFD was neither different among the different antifungal agents (P = .675) nor between patients with active and stable IPA (P = .080). The 1-year cumulative incidence of IFD and IPA relapse was 27.3% ± 4.5% and 24.7% ± 4.4%, respectively. Our data indicate that SAP with antifungal agents based on initial antifungal therapy has favorable efficacy and safety in allo-HSCT recipients with prior IPA. Active IPA might not increase the risk of breakthrough IFD after transplantation. [ABSTRACT FROM AUTHOR]

Deoxyribonucleic acid (DNA) lesions encountered during replication are often bypassed using DNA damage tolerance (DDT) pathways to avoid prolonged fork stalling and allow for completion of DNA replication. Rad18 is a central E3 ubiquitin ligase in DDT, which exists in a monoubiquitinated (Rad18•Ub) and nonubiquitinated form in human cells. We find that Rad18 is deubiquitinated when cells are treated with methyl methanesulfonate or hydrogen peroxide. The ubiquitinated form of Rad18 does not interact with SNF2 histone linker plant homeodomain RING helicase (SHPRH) or helicase-like transcription factor, two downstream E3 ligases needed to carry out error-free bypass of DNA lesions. Instead, it interacts preferentially with the zinc finger domain of another, nonubiquitinated Rad18 and may inhibit Rad18 function in trans. Ubiquitination also prevents Rad18 from localizing to sites of DNA damage, inducing proliferating cell nuclear antigen monoubiquitination, and suppressing mutagenesis. These data reveal a new role for monoubiquitination in controlling Rad18 function and suggest that damage-specific deubiquitination promotes a switch from Rad18•Ub-Rad18 complexes to the Rad18-SHPRH complexes necessary for error-free lesion bypass in cells. [ABSTRACT FROM AUTHOR]

This paper presents a new three-level zero-voltage switching (ZVS) dc/dc converter for high input voltage applications. There are two ZVS circuits in the proposed converter to share load current. Thus, the size of the output chokes is reduced. These two circuits use the same power switches. Thus, the proposed converter has less switch counts compared with the conventional parallel three-level ZVS dc/dc converter. In the proposed converter, each circuit combines one half-bridge converter and one three-level converter. The transformer secondary windings of two converters are connected in series to reduce the size of output inductor. The voltage stress of each power switch is limited at one-half of input voltage due to three-level circuit topology. Based on the resonant behavior by the output capacitance of active switches and the leakage inductance (or external inductance) at the transition interval, power switches are turned on at ZVS within the desired load range. Experiments based on a 1.5 kW prototype are provided to demonstrate the performance of the proposed converter. [ABSTRACT FROM AUTHOR]

Gene duplication is the primary source of new genes and novel functions. Over the course of evolution, many duplicate genes lose their function and are eventually removed by deletion. However, some duplicates have persisted and evolved diverse functions. A particular challenge is to understand how this diversity arises and whether positive selection plays a role. In this study, we reconstructed the evolutionary history of the class III peroxidase (PRX) genes from the Populus trichocarpa genome. PRXs are plant-specific enzymes that play important roles in cell wall metabolism and in response to biotic and abiotic stresses. We found that two large tandem-arrayed clusters of PRXs evolved from an ancestral cell wall type PRX to vacuole type, followed by tandem duplications and subsequent functional specification. Substitution models identified seven positively selected sites in the vacuole PRXs. These positively selected sites showed significant effects on the biochemical functions of the enzymes. We also found that positive selection acts more frequently on residues adjacent to, rather than directly at, a critical active site of the enzyme, and on flexible regions rather than on rigid structural elements of the protein. Our study provides new insights into the adaptive molecular evolution of plant enzyme families. [ABSTRACT FROM AUTHOR]

Weshow that the chlorite–trithionate reaction is “supercatalytic”;i.e., the formal kinetic order of the autocatalyst H+is2. A simple model is proposed and discussed to describe the unusualconcentration dependencies of one-dimensional front propagation foundexperimentally. It is also demonstrated that at relatively wide concentrationranges the linear two-dimensional front initiated loses its stability,giving rise to an appearance of cellular structures in a convection-freesystem. Compared to the chlorite–tetrathionate reaction, however,this system is much more stable at alkaline conditions, even for hours;therefore, no side reactions can be taken into consideration to checkwhether they may have any side effects on the evolution of spatiotemporalstructures. [ABSTRACT FROM AUTHOR]

A new zero-voltage switching (ZVS) dc converter for high input voltage and high output current applications is presented in this paper. Two three-level pulse-width modulation (PWM) circuits with the same active switches connected in parallel at the output side are adopted to achieve load current sharing and to decrease current stress of rectifier diodes. The center-tapped rectifiers are adopted at the secondary side to have only one diode conduction loss in the forward current path. The series resonant tank of three-level converter is used to achieve ZVS turn-on for all power switches and zero-current switching for all rectifier diodes within nearly entire load range. Thus, the switching losses of power switches are reduced and the reverse recovery losses of rectifier diodes are eliminated. In order to overcome the drawback of a wide range of switching frequency in conventional series resonant converters, the fixed frequency pulse-width modulation is adopted to regulate the output voltage. The series-connected transformers are used in the primary and secondary sides to share and balance the load current. Finally, experiments based on a laboratory prototype are provided to verify the operation principle and demonstrate the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

The dynamic behaviors of magnetic fluid-lubricated slider bearings have been investigated in this paper. For the slider bearing with an inclined film profile, the use of magnetic fluids as lubricants is found to provide an increase in the load carrying capacity, and the stiffness and damping coefficients as compared to the case of a conventional viscous fluid. The dynamic characteristics of slider bearings are improved by using magnetic fluid lubricants together with the application of magnetic fields. [ABSTRACT FROM AUTHOR]

Viral infections are important causes of morbidity and mortality after allogeneic stem cell hematopoietic transplantation (allo-HSCT). Although most viral infections present with asymptomatic or subclinical manifestations, viruses may result in fatal complications in severe immunocompromised recipients. Reactivation of latent viruses, such as herpesviruses, is frequent during the immunosuppression that occurs with allo-HSCT. Viruses acquired from community, such as the respiratory and gastrointestinal viruses, are also important pathogens of post-transplant viral diseases. Currently, molecular diagnostic methods have replaced or supplemented traditional methods, such as viral culture and antigen detection, in diagnosis of viral infections. The utilization of polymerase chain reaction facilitates the early diagnosis. In view of lacking efficacious agents for treatment of viral diseases, prevention of viral infections is extremely valuable. Application of prophylactic strategies including preemptive therapy reduces viral infections and diseases. Adoptive cellular therapy for restoring virusspecific immunity is a promising method in the treatment of viral diseases. [ABSTRACT FROM AUTHOR]

Background: Gene transfer into many cell types has been successfully used to develop alternative and adjunct approaches to conventional medical treatment. However, effective transfection of postmitotic neurons remains a challenge. The aim of this study was to develop a method for gene transfer into rat primary dorsal root ganglion neurons using sonoporation. Methods: Dissociated cells from adult rat dorsal root ganglion (DRG) cells were sonicated for 1-8 s at 2.5-10 W to determine the optimal ultrasound duration and power for gene transfection and cell survival. Transfection efficiency was compared between sonoporation, liposome and lentiviral vector gene transfer techniques. Results: The optimum ultrasound intensity was 5 W for 2 s and yielded an efficiency of gene transfection of 31% and a survival rate of 35%. Conclusions: Sonoporation can be optimized to minimize cell death and yield a high percentage of transfected neurons and that this technique can be easily applied to primary cultures of rat dorsal root ganglion neurons. [ABSTRACT FROM AUTHOR]

The solar (S) and lunar (L) variations of geomagnetic fields at the horizontal (H), declination (D), and the downward vertical component data (Z) are modeled by the Chapman-Miller method with four order harmonics. In this paper, we compare S and L variations of the geomagnetic total intensity field using a consistent method with 3-component data for seasonal variations (summer, winter, and equinox) for three distinct phases during the years 1988 - 2007. The results show that consistency in the S and L variations for geomagnetic total intensity indicates normal stations and discrepancies are occurred due to data quality. In application, consistent results also prove that the function of the magnetometers at TW was normal and that large anomalies were certainly in existence during the Chia-Yi earthquake. [ABSTRACT FROM AUTHOR]

A soft-switching converter is presented in this pa- per to achieve a zero-voltage-switching (ZVS) turn on for all switches. Two half-bridge converters with asymmetric pulsewidth-modulation scheme are connected in parallel to control the output voltage at the desired value and achieve load-current sharing. Based on the output capacitance of power switches and the resonant inductance, including the external inductance and the transformer leakage inductance, the resonance can be achieved at the transition interval of power switches. Therefore, the ZVS turn on of power switches can be realized. The peak voltage of the power switches is limited to input dc voltage. The center-tapped rectifier is adopted at the transformer secondary side to achieve a full-wave rectification. Operation principles, steady-state analysis, and design equations of the proposed converter are discussed in detail. Finally, experimental results based on a 240-W prototype are provided to verify the performance and the feasibility of the proposed converter. [ABSTRACT FROM AUTHOR]

In this paper, an interleaved soft-switching converter with ripple-current cancellation is presented to achieve zero-voltage-switching (ZVS) turn-on and load current sharing. In order to achieve ZVS turn-on, an active snubber is connected in parallel with the primary winding of the transformer. The energy stored in the transformer leakage inductance and magnetizing inductance can be recovered so that the peak voltage stress of switching devices is limited. The resonance at the transition interval is used to realize ZVS turn-on of all switches. In order to achieve three-level pulsewidth-modulation (PWM) scheme, an addition fast-recovery diode is used in the converter. Three-level PWM scheme can reduce the ac ripple current on the output inductor such that the output inductor can be reduced. The current-doubler rectifier is adopted in the secondary side of the transformer to reduce the transformer secondary-winding current and output voltage ripple by canceling the current ripple of two output inductors. The output voltage is controlled at the desired value using the interleaved PWM scheme. These features make the proposed converter suitable for the dc-dc converter with high out- put current. The operation principles, steady state analysis, and design equations of the proposed converter are provided in detail. Finally, experiments based on a 600-W (12 V/50 A) prototype are provided to verify the effectiveness and feasibility of the proposed converter. [ABSTRACT FROM AUTHOR]

Rainbands are essential to tropical cyclones (TCs), significantly affecting TC structure and intensity change. High‐resolution synthetic aperture radar (SAR) imagery can capture the footprints of rainbands caused by rain‐induced sea surface roughness modification. Using 464 SAR TC images, we investigated the rainband‐occurrence probability of TCs under different hemispheres, local times (LTs), intensities, and ocean basins. Results show that the rainband‐occurrence probability is highest in the downshear‐left quadrant for Northern Hemisphere TCs (downshear‐right quadrant for Southern Hemisphere TCs). For Northern Hemisphere TCs, the rainband‐occurrence probability is overall higher in the early morning (LT), and the peak region of rainband‐occurrence probability appears farther from the TC center in the evening (LT). Compared with weak TCs, the rainband‐occurrence probability becomes higher for strong TCs in the Northern Hemisphere. Furthermore, TCs have a higher rainband‐occurrence probability in the Northwest Pacific than in the North Atlantic and Northeast Pacific. Plain Language Summary: Rainbands are a salient feature of tropical cyclones (TCs) and are closely related to TC structure and intensity change. Synthetic aperture radar (SAR) can capture the sea surface imprint of rainbands beneath clouds caused by rain‐induced sea surface roughness modification. Using 464 SAR TC images, we made 464 rainband‐annotated data. The data were mapped to grid nodes spaced at 0.027 times the radius of max winds in a coordinate system with the origin at the TC center and the y‐axis in the vertical wind shear direction. Then, the data were composited to estimate and further investigate the rainband‐occurrence probability of TCs under different hemispheres, local times (LTs), intensities, and ocean basins. Results show that the rainband‐occurrence probability is highest in the downshear‐left quadrant for Northern Hemisphere TCs (downshear‐right quadrant for Southern Hemisphere TCs). For Northern Hemisphere TCs, the rainband‐occurrence probability is overall higher in the early morning (LT), and the peak region of rainband‐occurrence probability appears farther from the TC center in the evening (LT). Compared with weak TCs, the rainband‐occurrence probability becomes higher for strong TCs in the Northern Hemisphere. Furthermore, TCs have a higher rainband‐occurrence probability in the Northwestern Pacific than in the North Atlantic and Northeast Pacific. Key Points: The sea surface imprint of tropical cyclone (TC) rainbands in many synthetic aperture radar images reveals their occurrence probabilityThe rainband‐occurrence probability is overall higher in the early morning than in the evening. The feature is more obvious in strong TCsThe peak region of the probability appears farther from the TC center in the evening than in the early morning [ABSTRACT FROM AUTHOR]

This paper presents the system analysis, design consideration, and implementation of a soft-switching zeta-flyback converter to achieve zero-voltage switching (ZVS). In the proposed converter, the zeta and flyback topologies are adopted in the output side to achieve the following features: to share the power components in the transformer primary side, to achieve the partial magnetizing flux reset, and to share the output power. The buck-boost type of active clamp is connected in parallel with the primary side of the isolation transformer to recycle the energy stored in the leakage inductor of isolated transformer and to limit the peak voltage stress of switching devices due to the transformer leakage inductor when the main switch is turned off. The active clamp circuit can make the switching devices to turn on at ZVS. Experimental results taken from a laboratory prototype rated at 240 W, input voltage of 150 V, output voltage of 12 V, and switching frequency of 150 kHz are presented to demonstrate the converter performance. Based on the experimental results, the circuit efficiency is about 90.5% at rated output power, and the output voltage variation is about 1%. [ABSTRACT FROM AUTHOR]

A new half-bridge converter with two current-doubler rectifiers is proposed. Two transformers are used in the proposed converter. The primary windings of two transformers are connected in series to reduce the voltage stress across the magnetizing inductor, since each magnetizing inductor voltage is equal to one half of the input voltage. Two current-doubler rectifiers at the secondary sides are connected in parallel to reduce the current stress of secondary winding since the secondary winding current is less than one half of the load current. The asymmetrical pulsewidth-modulation technique is used in the pro- posed converter to regulate the direct current output voltage. The transformer leakage inductance and the output capacitance of switching switches are resonant during the transition interval between two switches in order to achieve zero voltage switching. The operation principle and design considerations of the proposed converter are provided. Experimental results for a 100-W (5 V/20 A) prototype are presented to verify the theoretical analysis and circuit performance. [ABSTRACT FROM AUTHOR]

A capacitor-clamped voltage-source inverter for active power filter operation under balanced and unbalanced conditions is proposed to suppress current harmonics and compensate the reactive power generated from the nonlinear loads. The adopted voltage-source inverter is based on a three-level capacitor-clamped topology to reduce the voltage stress of power semiconductors. Two control loops are used in the control scheme to achieve harmonic and reactive currents compensation and to regulate the inverter dc side voltage. In the adopted inverter, the neutral point voltage is compensated by a voltage compensator to obtain the balanced capacitor voltages on the dc side. In order to control the flying capacitor voltages, two redundant states in each inverter leg can be selected to compensate the flying capacitor to obtain a better voltage waveform with low harmonic contents on the ac terminals. The balanced and sinusoidal line currents are drawn from the ac source under the balanced and unbalanced conditions. The feasibility of the proposed scheme is confirmed through experimental results. [ABSTRACT FROM AUTHOR]

A three-phase four-wire power factor corrector based on neutral-point-clamped (NPC) topology is adopted to reduce the current harmonics and increase the input power factor. Using the NPC topology, the voltage stress of power switches can be reduced to the half of the dc-link voltage. With the dc-link voltage controller and the phase locked loop circuit, the balanced and sinusoidal line currents can be drawn from the ac supply system under the balance and unbalance mains voltages. The hysteresis current comparators are adopted in the current control loop to track the line current commands. Three voltage levels are generated on the ac terminal to the neutral point. Simulations and experiments are provided to verify the validity and the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

A new ac line conditioner is presented for high input power factor and clean ac output voltages for isolating the linear or nonlinear loads. A three-phase two-leg switching mode rectifier with neutral-point-clamped topology Is proposed to draw the sinusoidal line currents from the ac mains. The carrier-based current controller Is used in the inner control loop to track the line current commands with unity power factor. The dc bus voltage controller Is adopted in the outer control loop to regulate the dc-link voltage. A voltage compensator is used to balance the neutral point voltage on the dc tank. A three-phase two-leg Inverter with neutral-point-clamped topology is adopted in the system to provide the clean ac output voltages to the critical or sensitive loads. The carder-based current control scheme is adopted to improve the instantaneous output voltages. Experimental results show the validity and effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Death-associated protein kinase (DAP kinase) is a proapoptotic, calcium/calmodulin-dependent serine/threonine kinase. Here, we report that DAP kinase phosphorylates the regulatory light chain of myosin H (MLC) both in vitro and in vivo, and that this phosphorylation occurs preferentially at residue Ser19. In quiescent fibroblasts, DAP kinase stabilizes stress fibers through phosphorylation of MLC, but it is dispensable for the formation of peripheral microfilament bundles. This cytoskeletal effect of DAP kinase occurs before the onset of apoptosis and does not require an intact death domain. In addition, DAP kinase is required for serum-induced stress-fiber formation, which is associated with the upregulation of its catalytic activity. Despite being both sufficient and necessary for the assembly or maintenance of stress fibers, DAP kinase is incapable of stimulating the formation of focal adhesions in quiescent cells. Moreover, it promotes the disassembly of focal adhesions but not stress fibers in cells receiving serum factors. Together, our results identify a novel and unique function of DAP kinase in the uncoupling of stress fibers and focal adhesions. Such uncoupling would lead to a perturbation of the balance between contractile and adhesion forces and subsequent cell detachment, which might contribute to its pro-apoptotic activity. [ABSTRACT FROM AUTHOR]

Proposes a single-phase alternating current (ac)/ac converter based on neutral-point-clamped scheme to perform unity input power factor and to provide a stable ac voltage to the critical loads. Regulation of the ac/direct current (dc) rectifier part to generate a unipolar pulsewidth modulation waveform on the ac terminal; Employment of the carrier-based current control scheme in the inner control loop to track the line current command; Adoption of a proportional-integral control to regulate the dc bus voltage.

Presents a study that developed a high power factor rectifier based on the neutral point clamped scheme. Background on the use of conventional diodes and phase-controlled rectifiers; Significance of power factor correctors and active power filters to harmonics elimination and reactive power compensation; Information on the full-bridge pulsewidth modulated rectifier; Examination of the power switches used in the proposed rectifier.

Focuses on a study concerning which examined the impact of various levels of information sharing on supply chain performance in electronic commerce. Discussion of the exchange of information between business partners; Effect of information sharing on transaction costs and inventory management; Application of the simulation system in supply chain.

Examines the control scheme of single-phase integrated power quality compensator. Principle of the active power filter (APF); Advantages of the power quality compensator scheme; Elimination of reactive power by APF.

With the development of altimeters’ retracking algorithms, the signal-to-noise ratio of altimeter data in coastal regions has been improved significantly in recent years. However, due to the complexity of coastal waves, the traditional satellite-buoy/satellite-satellite collocation method using a spatial-temporal window, which is widely used in the evaluation of significant wave height (SWH) measurements of altimeters in the open ocean, is not reliable because coastal waves can vary significantly even in a small window. This makes it difficult to quantitatively evaluate the errors of altimeter coastal SWH observations. This study proposes an automated dynamic collocation method to solve this problem. The method combines SWH from coastal buoy observations and numerical wave model (NWM) outputs to generate an SWH reference field. The coastal altimeter observations can then be compared with this reference dataset. To test the effectiveness of the method, the SWH data from Sentinel-3A (S3A) synthetic aperture radar (SAR) mode in the coastal region of southwest England were evaluated. The results indicate that the coastal SWHs from the S3A SAR mode is good quality with an overall root mean square error of about 0.3 m when the offshore distance is more than 10 km. The results also show that the presented method works better than previous methods for the evaluation of coastal altimeter SWH observations. This method can be applied in future studies to evaluate and improve the performance of other coastal remotely sensed SWH observations. [ABSTRACT FROM AUTHOR]

Focuses on a study that proposed a single-phase switching mode rectifier for three-level pulse width modulation (PWM) to achieve high input power factor, low current harmonics, low total harmonic distortion and simple control scheme. Details on the principle of operation of the rectifier; Advantages of using a three-level PWM scheme; Control algorithms; Simulation and experimental results; Conclusions.

Proposes a multi-agent information system to simulate business processes. Incorporation of reinforcement learning to obtain better process adaptability; Evaluation of the resulting business process simulation and learning system; Order fulfillment process in supply chain networks.

Presents a control scheme for a single-phase alternating current-to-direct current converter with three level pulsewidth modulation. Circuit configuration; System analysis of the adopted single-phase three-level rectifier; Control algorithm.

Presents a study that examined pulsewidth modulation (PWM) control strategies for a single-phase power-factor-correction (PFC) alternating current/direct current converter. Benefits of high power density and low current distortion in industrial applications; Performance evaluation of the PWM schemes and circuit modeling equations; Results and discussion.

The interferometric imaging radar altimeter (InIRA) aboard the Chinese Tiangong-2 space laboratory is the first spaceborne imaging radar working at low incidence angles. This study focuses on the retrieval of significant wave heights (SWHs) from InIRA data. The retrieved SWHs can be used for correcting the sea state bias of InIRA-derived sea surface heights and can supplement SWH products from other spaceborne sensors. First, we analyzed tilt, range bunching and velocity bunching wave modulations at low incidence angles, and we found clear dependencies between the SWH and two defined factors, range and azimuth integration, for ocean waves in the range and azimuth directions, respectively. These dependencies were further confirmed using InIRA measurements and collocated WaveWatch III (WW3) data. Then, an empirical orthogonal SWH model using the range and azimuth integration factors as model inputs was proposed. The model was segmented by the incidence angle, and the model coefficients were estimated by fitting the collocation at each incidence angle bin. Finally, the SWHs were retrieved from InIRA data using the proposed model. The retrievals were validated using both WW3 and altimeter (JASON2, JASON3, SARAL, and HY2A) SWHs. The validation with WW3 data shows a root mean square error (RMSE) of 0.43 m, while the average RMSE with all traditional altimeter data is 0.48 m. This indicates that the InIRA can be used to measure SWHs. [ABSTRACT FROM AUTHOR]

Proposes a control scheme for single-phase three-level pulsewidth modulation bridge rectifier with high power factor correction. Composition of the main circuit; Balance of capacitor voltages; Derivation of the supply current demand; Advantages of using a three-level rectifier; Verification of the high power factor and low harmonic currents at the input of the rectifier.

Provides information on a study in which the low-frequency noise of lattice-matched indium-phosphorus (InP) high electron mobility transistors (HEMT) gate recess, etched with a highly selective dry etching process and with conventional wet etching, were studied. Introduction on the development of HEMT; Examination of the drain and gate current noise under all bias conditions and temperatures; Conclusions.