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In this article, a novel p-GaN high-electron-mobility transistor (HEMT) with a built-in Schottky barrier diode (SBD) is proposed and investigated by TCAD simulation. The anode contact of the integrated SBD is isolated from the ohmic contact of the source electrode by a p-GaN isolation region. The cathode of the SBD is connected to the drain electrode. In the proposed Schottky barrier diode/HEMT (SB-HEMT), a channel under the p-GaN isolation region is turned on during forward conduction to further reduce the specific on-resistance ( $R_{{on},sp}$ ). With a minimum sacrifice on $R_{{on},sp}$ , the reverse on-state voltage, $V_{R-{on}}$ (at a current density of 50 mA/mm), for the SB-HEMT is reduced by 33% (from 2.43 to 1.62 V) when compared with a conventional HEMT (C-HEMT). Compared with the C-HEMT with a separate on-chip SBD (C-HEMT/SBD), the SB-HEMT shows much better trade-off between $V_{R-{on}}$ and $R_{{on},sp}$ . The total switching loss ( $E_{total}$ ) of the proposed SB-HEMT with resistive load is lower than that of the C-HEMT and is reduced by up to 21% when compared with that of the C-HEMT/SBD with different area ratio between the HEMT and SBD regions.

Conventional di/dt and dv / dt control and gate protection techniques for gallium nitride (GaN) power transistors usually employ external controllers, isolation circuits, discrete pull-up, and pull-down resistors. With large number of components, power modules become more complex and may introduce additional parasitic. Gate driver ICs with segmented output stages and dynamic gate driving have been reported previously to be effective in simultaneously suppressing gate ringing and overshoot voltage while maintaining fast switching speed. However, the programming for dynamic gate driving is rather complicated, requiring the user to load a sequence of driving patterns obtained from trial and error ahead of time. This article presents a gate driver IC for E-mode GaN power transistors with seven segmented output stages. More importantly, it offers a simplified programming method for the dynamic gate driving pattern. The optimal gate drive pattern can be defined by simply adjusting one external bias resistor. The proposed method eliminates the complex trial and error digital control, and can potentially promoting the wider acceptance of dynamic gate driving by the industry. The timing resolution for the gate drive pattern can be varied in steps from 0.5 to 5 ns. It can also be used to drive many commercially available GaN power transistors.

BackgroundNeuropsychiatric symptoms (NPSs) belong to a category of non-motor symptoms of Parkinson's disease (PD), which seriously compromise the quality of life and prognosis of PD. This study focused on the correlations between NPSs, free radicals, neuroinflammatory factors, and neuropathological proteins in cerebrospinal fluid (CSF) in patients with PD, aiming to provide insights into the potential mechanisms and therapeutic target for PD with NPSs (PD-NPSs).MethodsIn total, 129 patients with PD were enrolled and assessed by the Neuropsychiatric Symptoms Inventory (NPI); they were divided into the PD-NPSs group (75 patients) and PD with no NPSs (PD-nNPSs) group (54 patients). The levels of hydrogen peroxide (H2O2) and nitric oxide (NO), and hydroxyl radical (·OH), anti-oxidative enzyme, neuroinflammatory factors, and neuropathological proteins in CSF from patients with PD were measured. The levels of the above variables were compared between PD-NPSs and PD-nNPSs groups, and correlation analyses among the above variables were conducted.Results(1) The levels of H2O2 and NO in CSF from the PD-NPSs group were significantly elevated compared with the PD-nNPSs group (p = 0.001), and NPI score positively correlated with the levels of H2O2 and NO (r = 0.283, P = 0.001; r = 0.231, P = 0.008). Reversely, total superoxide dismutase (tSOD) activity in CSF from the PD-NPSs group was significantly reduced compared with the PD-nNPSs group (p = 0.011), and negatively correlated with NPI score (r = −0.185, p = 0.036). (2) The tumor necrosis factor (TNF)-α level in CSF from the PD-NPSs group was significantly decreased compared with the PD-nNPSs group (p = 0.002) and negatively correlated with NPI score (r = −0.211, p = 0.016). (3) The total tau (T-tau) level in CSF from the PD-NPSs group was significantly higher than in the PD-nNPSs group (p = 0.014) and positively correlated with the NPI score (r = 0.167, p = 0.060). (4) The levels of H2O2 and NO positively correlated with the T-tau level in CSF from the PD-NPSs group (r = 0.183, p = 0.039; r = 0.251, P = 0.004), and the levels of TNF-α and T-tau showed a negative correlation (r = −0.163, p = 0.067).ConclusionOxidative distress characterized by the elevations of H2O2 and NO levels may closely correlate with the neurodegeneration in brain regions related to PD-NPSs. Thus, therapeutic antioxidants may become an important target for PD-NPSs therapy.

An accurate method for the evaluation of breakdown voltages (BVs) in the superjunction-like (SJ-like) power devices is presented. This brief investigates the conventional SJ (c-SJ), the insulator pillar SJ (I-SJ), and the high-permittivity ( $\text{H}{k}$ ) structures. Based on the numerical calculations of the electric field line (EFL) distribution, the electric field profiles along the EFLs can be accurately obtained. This ensures the accurate determination of the impact ionization integrals and BV. The technology computer-aided design (TCAD) simulations confirm the validity of the proposed method. The proposed method could be of great significance for the optimization of the specific ON-resistance ( ${R} _{ \text {ON,sp}}$ ) and could provide a better understanding of the SJ-like power devices.

Gallium nitride (GaN) power transistors have attracted significant interest in the power electronics industry over the past decade as the next-generation power semiconductor devices. GaN power transistors are suitable for high power and high frequency applications due to their higher electron mobility, temperature tolerance, electrical conductivity, critical breakdown electric field, and breakdown voltage compared to the conventional silicon-based transistors and other wide bandgap (WBG) power transistors. In particular, GaN-on-silicon (GaN-on-Si) technology has opened up the possibility of manufacturing high-performance, low-cost WBG power devices in silicon-compatible fabrication facilities. The first GaN power transistor structure to be developed was the normally-ON depletion mode (D-mode) device. It relies on the highly mobile two-dimension electron gas (2DEG) at the GaN/AlGaN epitaxial layers’ interface to provide very low on-resistance. The normally-OFF enhancement mode (E-mode) GaN power transistor soon became available by controlling the 2DEG using various gate structures. This paper provides a review of the developments of GaN power transistors followed by a survey on current state-of-the-art GaN power technologies and applications, including comparisons between GaN growth substrates and developments of enhancement mode (E-mode) device structures and their process techniques. Moreover, developments of power module designs are also addressed, including gate driver designs and their requirements, and packaging techniques for power transistors and power modules.

Aloe vera (L.) Burm.f. is widely used as laxative drugs, cosmetics, and functional food due to a variety of therapeutic effects. However, several studies indicated a colonic carcinogenic activity of Aloe vera. But the underline mechanism has not been well clarified. This study aimed to explore the potential mechanism at the post-transcriptional level. Identification of Differential Expressed Alternative Splicing (DEAS) genes and events and the corresponding functional enrichment analyses were conducted on RKO cells after treated with Aloe vera aqueous extract and its two active components, aloin and aloesin. And RT-qPCR was conducted for validation. Results indicated that they induced 2200, 2342 and 2133 DEAS events, respectively. The GO enrichment and the COG classification results of DEAS genes showed that they were associated with transcription, as well as functions like signal transduction mechanisms. Moreover, DEAS genes related to the two colorectal cancerous pathways, Wnt and Notch pathways, were annotated. In conclusion, aloe extract, aloin and aloesin significantly regulated the DEAS profile of RKO cells. The colonic carcinogenicity of Aloe vera may due to its post-transcriptional regulatory activity through Alternative Splicing (AS) on genes, especially on Wnt-related and Notch-related key genes.

A new lateral power metal-oxide-semiconductor field-effect transistor (MOSFET) with dual conduction paths and high- ${k}$ passivation is proposed. The high- ${k}$ passivation enables the dual conduction paths to realize the double reduced surface field (RESURF) action and facilitates the formation of an accumulation layer during forward conduction. The proposed device offers a 42% reduction in specific on-resistance ( ${R}_{{ON},{SP}}{)}$ when compared to a similar size baseline device with the same breakdown voltage (BV). The technology computer-aided design (TCAD) simulation results, based on a $0.5~\mu \text{m}$ bipolar-CMOS-DMOS (BCD) compatible process, show that the proposed device is able to provide a ${R}_{{ON},{SP}}$ as low as 0.28 $\text{m}\Omega \cdot $ cm2 with a BV of 92 V.

The mechanism underlying the hypoglycemic effect of the simultaneous use of metformin and anthocyanin-rich foods is not yet clear. Hence, the effects and possible mechanisms of action of these substances, alone and in combination, were evaluated in insulin-resistant HepG2 cells and a diabetic mouse model. The results indicated that anthocyanin and metformin had a significant synergistic effect on glucose consumption (CI0.9) compared with metformin alone in HepG2 cells. In the mouse model, combined treatment (50 and 100 mg/kg metformin + anthocyanin groups) demonstrated synergistic restorative effects on the blood glucose level, insulin resistance, and organ damage in the liver, pancreas, and ileum. Additionally, combined metformin and anthocyanin treatment suppressed protein tyrosine phosphatase 1B expression and regulated the PI3K/AKT/GSK3β pathway. Combined treatment also altered the gut microbial composition and structure by increasing the relative abundance of beneficial bacteria and the short-chain fatty acid content. These results suggest that the use of anthocyanins can enhance the efficacy of metformin treatment for hyperglycemia and provide a reference for further clinical research regarding nutrition and supplementary treatment.

A miniaturized atomic spin-exchange relaxation-free (SERF) co-magnetometer measures angular velocity using a balanced polarimetry technique which is easily affected by the laser power. A laser power closed-loop control system is usually used to suppress the fluctuation of the laser power. Although this method can greatly eliminate the fluctuation of the in-loop laser power (the feedback laser), it cannot fully eliminate the fluctuation of the out-of-loop laser power (the signal measurement laser). This leads to SERF gyroscope laser power error, which reduces the inertial measurement accuracy. In this paper, the influence mechanism of the split ratio (the ratio of the in-loop laser power to the out-of-loop laser power) on the out-of-loop laser power control accuracy is analyzed by establishing a laser power transmission model inside and outside the loop. Moreover, a method is developed to improve the out-of-loop laser power stability by optimizing the split ratio. Comparative experiments showed that the relative Allan standard deviation of the out-of-loop laser power decreased from 5.48 × 10−6 to 2.62 × 10−6 at 100 s, and decreased by an order of magnitude from 1.76 × 10−5 to 3.30 × 10−6 at 1000 s. Correspondingly, the rate ramp coefficient in the Allan standard deviation curve of the SERF gyroscope test data decreased from 1.312 [(°/h)/h] to 0.246 [(°/h)/h]. And the bias stability increased from 0.032 °/h to 0.019 °/h. Therefore, the proposed method can improve the long-term stability of the probe laser power and effectively suppress the laser power error of the SERF gyroscope.

A novel moderately thermophilic, anaerobic, heterotrophic bacterium (strain SY095T) was isolated from a hydrothermal vent chimney located on the Southwest Indian Ridge at a depth of 2730 m. Cells were Gram-stain-positive, motile, straight to slightly curved rods forming terminal endospores. SY095T was grown at 45–60 °C (optimum 50–55 °C), pH 6.0–7.5 (optimum 7.0), and in a salinity of 1–4.5 % (w/v) NaCl (optimum 2.5 %). Substrates utilized by SY095T included fructose, glucose, maltose, N-acetyl glucosamine and tryptone. Casamino acid and amino acids (glutamate, glutamine, lysine, methionine, serine and histidine) were also utilized. The main end products from glucose fermentation were acetate, H2 and CO2. Elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and Fe(III) were not used as terminal electron acceptors. The predominant cellular fatty acids were C14 : 0 (60.5%) and C16 : 0 (7.6 %). The main polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. No respiratory quinones were detected. The chromosomal DNA G+C content was 30.8 mol%. The results of phylogenetic analysis of the 16S rRNA gene sequences indicated that SY095T was closely related to Crassaminicella profunda Ra1766HT (95.8 % 16S rRNA gene sequence identity). SY095T exhibited 78.1 % average nucleotide identity (ANI) to C. profunda Ra1766HT. The in silico DNA–DNA hybridization (DDH) value indicated that SY095T shared 22.7 % DNA relatedness with C. profunda Ra1766HT. On the basis of its phenotypic, genotypic and phylogenetic characteristics, SY095T is suggested to represent a novel species of the genus Crassaminicella , for which the name Crassaminicella thermophila sp. nov. is proposed. The type strain is SY095T (=JCM 34213=MCCC 1K04191). An emended description of the genus Crassaminicella is also proposed.

A hyperthermophilic, strictly anaerobic archaeon, designated strain SY113T, was isolated from a deep-sea hydrothermal vent chimney on the Southwest Indian Ridge at a water depth of 2770 m. Enrichment and isolation of strain SY113T were performed at 85 °C at 0.1 MPa. Cells of strain SY113T were irregular motile cocci with peritrichous flagella and generally 0.8–2.4 µm in diameter. Growth was observed at temperatures between 50 and 90 °C (optimum at 85 °C) and under hydrostatic pressures of 0.1–60 MPa (optimum, 27 MPa). Cells of SY113T grew at pH 4.0–9.0 (optimum, pH 5.5) and a NaCl concentration of 0.5–5.5 % (w/v; optimum concentration, 3.0 % NaCl). Strain SY113T was an anaerobic chemoorganoheterotroph and grew on complex proteinaceous substrates such as yeast extract and tryptone, as well as on maltose and starch. Elemental sulphur stimulated growth, but not obligatory for its growth. The G+C content of the genomic DNA was 55.0 mol%. Phylogenetic analysis of the 16S rRNA sequence of strain SY113T showed that the novel isolate belonged to the genus Thermococcus . On the basis of physiological characteristics, average nucleotide identity values and in silico DNA–DNA hybridization results, we propose a novel species, named Thermococcus aciditolerans sp. nov. The type strain is SY113T (=MCCC 1K04190T=JCM 39083T).

Hadal trenches are the deepest but underexplored ecosystems on the Earth. Inhabiting the trench bottom is a group of micro-organisms termed obligate piezophiles that grow exclusively under high hydrostatic pressures (HHP). To reveal the genetic and physiological characteristics of their peculiar lifestyles and microbial adaptation to extreme high pressures, we sequenced the complete genome of the obligately piezophilic bacterium Moritella yayanosii DB21MT-5 isolated from the deepest oceanic sediment at the Challenger Deep, Mariana Trench. Through comparative analysis against pressure sensitive and deep-sea piezophilic Moritella strains, we identified over a hundred genes that present exclusively in hadal strain DB21MT-5. The hadal strain encodes fewer signal transduction proteins and secreted polysaccharases, but has more abundant metal ion transporters and the potential to utilize plant-derived saccharides. Instead of producing osmolyte betaine from choline as other Moritella strains, strain DB21MT-5 ferments on choline within a dedicated bacterial microcompartment organelle. Furthermore, the defence systems possessed by DB21MT-5 are distinct from other Moritella strains but resemble those in obligate piezophiles obtained from the same geographical setting. Collectively, the intensive comparative genomic analysis of an obligately piezophilic strain Moritella yayanosii DB21MT-5 demonstrates a depth-dependent distribution of energy metabolic pathways, compartmentalization of important metabolism and use of distinct defence systems, which likely contribute to microbial adaptation to the bottom of hadal trench.

Dead-times are necessary in switching output stage to avoid shoot-through current between the high side (HS) and the low side (LS) power transistors. However, excessively long dead-times can lead to unwanted reverse conduction and power loss. Sensing the duration of reverse conductions are especially difficult for high-voltage enhancement mode ( e -mode) gallium nitride (GaN) HEMTs due to their fast switching speed. High-precision sensing circuits are required for dead-time correction as the load current changes and to withstand large voltage swings. Traditional CMOS-based sensing circuits (e.g. standard logic gates) are not suitable for GaN-based converters as they can only handle limited voltage ranges. In addition, severe undershoots (up to -4 V) may damage the sensing circuit. Here, a gate driver IC for e -mode GaN power output stages capable of detecting the presence of reverse conduction with a best resolution of 0.66 ns, a dead-time adjustment resolution of 0.33 ns, and with on-chip closed-loop control is presented. In addition, a novel reverse conduction sensing circuit that can accommodate the large voltage swings at the switching node (SW) is also described.

Conventional insulated gate bipolar transistor (IGBT) current sensing and protection techniques usually employ discrete sensors, such as lossy shunt resistors, and may involve accessing the high-voltage collector load of the IGBT. This would normally present difficulties for integration. This paper presents an IGBT gate driver IC with a collector current sensing circuit and an on-chip CPU for local data processing. This IC is prototyped using a TSMC 0.18 μm 40 V BCD Gen-2 process. The collector current sensing technique is based on the unique Miller plateau relationship between the gate current and collector current ( $I_{C}$ and $I_{G}$ ) for a particular gate resistance ( $R_{G}$ ). It allows a cycle-by-cycle measurement of IC during both turn- on and turn- off transients without any extra discrete components. The temperature variation is compensated internally by the on-chip CPU using polynomial curve fitting. This technique only monitors the low-voltage signal at the gate terminal, without the need to handle any high-voltage signal on the collector/load side. Measurements using a double pulse test setup show an accuracy of ±0.5 A over the current ranges of 1–30 A for turn- on and 1–50 A for turn- off from 25 to 75 °C.

At high altitude, wastewater aeration efficiency is low, which is detrimental to nitrification in conventional biological nitrogen removal. The combined partial nitritation and anaerobic ammonium oxidation (CPNA) process requires little oxygen and can be appropriate in low-pressure conditions. As such, in this study, we investigated the effect of air pressure on CPNA using a laboratory-scale reactor. We found that low air pressure promoted the removal of total inorganic nitrogen (TIN), achieving a TIN removal rate of 43,000 mg·N/(kg·VSS·d). The secretion of extracellular polymeric substances under low air pressure was not significantly different from that under ordinary air pressure, indicating no adverse effects on microbial aggregation ability, stability, or settleability. The abundance of aerobic ammonia-oxidizing bacteria (AeAOB) increased from 0.2% to 5.6%, and the activity of anaerobic ammonia-oxidizing bacteria (AnAOB) enhanced, giving AeAOB and AnAOB a competitive advantage over nitrite-oxidizing bacteria, thus forming a microbial community structure favorable to the CPNA process. Our further analysis of the results of batch tests in serum bottles confirmed the positive effect of low air pressure on the anaerobic ammonium oxidation (anammox) process, with a 28.5% ± 1.9% improvement in the specific anammox rate at 70 kPa compared with 100 kPa. AnAOB activity increased, which was reflected in the intracellular heme content increasing from 0.56 ± 0.18 μmol/(g·VSS) at 100 kPa to 2.56 ± 0.20 μmol/(g·VSS) at 70 kPa. We clarified the CPNA-process-promoting effect of low air pressure, which shows potential for nitrogen removal in high-altitude regions.

The application of a segmented gate driver (SGD) to detect aging and provide automated compensation for SiC MOSFETs is presented. By dynamically modifying the gate resistance during switching transients, we can stretch the Miller plateau (MP) duration. The MP level is used as an indicator for the health condition of the SiC power MOSFET. A digital control circuit analyzes the aging effect and provides a control signal to an integrated boost converter, which powers the gate drive voltage. In this manner, the gate drive voltage can be adjusted to compensate for changes in the MOSFET performance. The same SGD can also be used to suppress gate ringing to protect the SiC power device against over/undershoot damage. This is of particular importance at elevated gate voltage.

Compact liquid cooled gallium nitride (GaN) intelligent power modules (IPMs) are fabricated using direct bonding methods. A half bridge module with 15 A GaN high electron mobility transistors (HEMTs) is flip-chip bonded on active metal brazed (AMB) substrates using pressureless nanosilver sintering. The AMB substrates are pre-brazed on a copper liquid cooler. The geometries of the AMB substrates and the GaN IPMs are determined based on thermal simulations using finite element analysis (FEA). The prototype GaN IPMs are tested in a buck converter configuration. The module temperatures are below 35 °C for up to 35 W of output power. The proposed process flow offers a simple IPM packaging solution to power semiconductor companies using prefabricated liquid coolers with brazed AMB substrates from automotive parts manufacturers.

To suppress excessive gate voltage swings during switching, a resistance is normally used to limit the charging rate of the gate capacitance (C G ). Modern solutions, such as segmented gate drivers, can be used to dynamically control the gate resistance R G to minimize ringing while maintaining the fast-switching speed of the transistor. The timing or dynamic pattern of the gate resistance is critical in the optimization of the device and circuit performance. Traditionally, this gate drive pattern is obtained via a trial-and-error or iterative procedure. This paper proposes a method to automatically determine the timing intervals by monitoring the gate signal (V GATE ) through slope sensing with analog filter and subsequent mixed-signal processing. The output timing indicator (T SEG ) is then fed back to the segmented gate driver IC to achieve automatic adjustments of the dynamic driving pattern. The proposed system is able to determine the optimum T SEG for dynamic gate driving. For the SiC power MOSFET used in our testing, segmented R G driving between 2.5 and 10 Ω does not hinder the switching speed, while keeping the undershoot of the SiC module to be within 1 V or 5% of the total applied gate voltage.

Intelligent power modules (IPMs) are critical components within electric vehicle (EV) power inverters that require effective liquid cooling. IPM manufacturers are constantly evolving their designs in lockstep with advancements in switching transistor technology to deliver more power with increased efficiency. In particular, the imminent arrival of new IPMs based on wide-bandgap semiconductors poses new thermal challenges due to smaller die areas and increased heat fluxes. The question arises whether the traditional liquid cooling strategies will be sufficient to cool the next generation of EV IPMs as semiconductor technology transitions from Si IGBTs, to SiC MOSFETs and GaN power HEMTs, with progressively decreasing die areas. In this paper, this question is explored through an analytical solution of the heat equation in a representative model of a typical EV IPM heat exchanger (HX). It is shown that there exists a practical thermal limit to traditional EV IPM HXs which must be addressed by IPM and automotive parts manufacturers together. Thermal benchmarking experiments, supported by numerical simulations, of two commercially available IPMs are performed, confirming no violations of the derived thermal limit.

Background Helicobacter pylori (H. pylori) infection has become an international public health problem, and antibiotic-based triple or quadruple therapy is currently the mainstay of treatment. However, the effectiveness of these therapies decreases due to resistance to multiple commonly used antibiotics. Sanguisorba officinalis L. (S. officinalis), a traditional Chinese medicine clinically used for hemostasis and treatment of diarrhea, has various pharmacological activities. In this study, in vitro antimicrobial activity was used for the preliminary evaluation of S. officinalis against H. pylori. And a pharmacology analysis approach was also utilized to elucidate its underlying mechanisms against H. pylori infection. Methods Micro-broth dilution method, agar dilution method, checkerboard assay, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used for the assessment of anti-bacterial activity. Active ingredients screening, GO analysis, KEGG analysis, construction of PPI network, molecular docking, and RT-qPCR were used to elucidate the underlying pharmacological mechanisms of S. officinalis against H. pylori infection. Results The minimum inhibitory concentration (MIC) values of S. officinalis against multiple H. pylori strains including clinically isolated multi-drug resistant (MDR) strains were ranging from 160 to 320 µg/ml. These results showed that S. officinalis had additive interaction with four commonly used antibiotics and could exert antibacterial effect by changing the morphology of bacteria without developing drug resistance. Through network pharmacology analysis, 8 active ingredients in S. officinalis were screened out for subsequent studies. Among 222 putative targets of S. officinalis, 49 targets were identified as potential targets for treatment of H. pylori infection. And these 49 targets were significantly enriched in GO processes such as protein kinase B signaling, protein kinase activity, protein kinase binding, and KEGG pathways such as Pathways in cancer, MicroRNAs in cancer, and TNF signaling pathway. Protein-protein interaction analysis yielded 5 core targets (AKT1, VEGFA, EGFR, SRC, CCND1), which were validated by molecular docking and RT-qPCR. Conclusions Overall, this study confirmed the in vitro inhibitory activity of S. officinalis against H. pylori and explored the possible pharmacological mechanisms, laying the foundation for further research and clinical application.

Gate overshoot voltage prevention when driving E-mode GaN-based HEMTs is essential for system reliability and EMI suppression. Active gate drivers have been demonstrated to suppress gate voltage overshoot while maintaining fast turn-on. However, they normally require complex driving patterns that are determined using trial and error approaches. In this paper, an active gate driver with an integrated pattern generator is proposed to simplify the control of the dynamic gate driving strength pattern. For best trade-off between overshoot and transition speed, the gate resistance (or gate driving strength) must remain low but with a large resistance switched in briefly during the turn-on transition period. Switch timing of the driving pattern varies with load conditions and the types of transistor. To simplify the programming of the driving pattern, the gate driving strength can be controlled by changing only one external bias resistor in the proposed design. This in turn sets the bias current of a delay chain to adjust the timing of the gate driving strength pattern. The proposed design aims to create a systematic approach to simplify the selection of the gate driving strength pattern.

Background Colorectal cancer (CRC) is a widespread cancer with high morbidity and mortality. Chemoresistance and metastasis are the current challenges for CRC treatment. Sanguisorba officinalis Linn. (called DiYu in Chinese, DY) is a Traditional Chinese medicine (TCM), which its root is long used as medicinal part. In our previous study, the aqueous extract of DY could inhibit the Wnt/β-catenin pathway and showed great antitumor effect against CRC. The Wnt/β-catenin pathway is involved in CRC chemoresistance and metastasis. However, there is little study on the antitumor and antimetastatic effects of DY on resistant CRC cells. The aim of this study is to explore the effect of aqueous extract of DY on the growth and metastasis of 5-fluorouracil (5-FU) sensitive and resistant CRC, and to elucidate the underlying molecular mechanism. Methodology In this study, cell viability, cell colony formation and apoptosis analyses were performed to verify the in vitro antitumor effect of DY on 5-FU-sensitive and -resistant CRC cells. Next, transwell assays were used to test the inhibition activity of DY on CRC migration and invasion. Western Blotting assays were carried out to identify the molecular mechanism underlying the efficacy of DY extract. Xenograft CRC nude mice model and tumor metastasis model were used to confirm the in vivo antitumor and antimetastatic effects of DY. Results DY inhibited cell proliferation and apoptosis via the upregulation of Bax, cleaved-caspase3 and cleaved-PARP proteins and downregulation of Bcl-2 protein. DY also inhibited cell migration and invasion via the downregulation of N-cadherin, vimentin and snail proteins and upregulation of E-cadherin protein, demonstrating that DY suppressed cell metastasis by reversing epithelial-to-mesenchymal transition (EMT) procession. Moreover, the protein expression levels of β-catenin in whole cell, cytoplasm and nucleus were decreased after DY treatment. Taken together, DY suppressed CRC cell growth and metastasis via inhibition of the Wnt pathway. Additionally, DY also demonstrated effective antitumor and anti-metastasis activities in vivo. Conclusions In conclusion, DY suppressed the growth and metastasis of 5-FU-sensitive and -resistant CRC via inhibition of the Wnt pathway, which indicated that DY could be a potential drug to treat CRC patients and improve clinic outcome.

Ethnopharmacological relevance Canarium album Raeusch. belongs to the Burseraceae family. Its ripe fruits, known as Qing Guo (QG) in Traditional Chinese Medicine (TCM), are used to treat sore throat, cough, and fish or crab poisoning. QG was reported to have antibacterial activity, and it exerted excellent anti-Helicobacter pylori (H. pylori) activity in our screening of abundant TCM. However, few studies have reported its anti-H. pylori activity and mechanism. Aim of study The commonly used eradication therapies for H. pylori infection are antibiotic-based therapies. With the increasing antibiotic resistance of H. pylori, interest in finding alternative therapies has been aroused. This study investigated the phytochemistry profile, in vitro anti-H. pylori activity and possible anti-bacterial mechanism of QG extracts. Materials and methods QG extracts were obtained by heat reflux extraction, ultrasonic extraction or liquid-liquid extraction with different solvents. The quantitative and qualitative phytochemical analyses were performed by colorimetric determination, high-performance liquid chromatography (HPLC), and UPLC-electrospray ionization mass spectrometry (ESI-MS). In vitro anti- H. pylori activity was assessed by broth micro-dilution method. Mechanism of action studies included morphological observation using electron microscopy, urease inhibition assay and determination of expression of virulence genes by RT-qPCR. Results All QG extracts especially ethyl acetate extract (QGEAE) were rich in phenolic components, with the minimum inhibitory concentrations (MICs) on H. pylori of 39–625 μg/ml and minimum bactericidal concentrations (MBCs) of 78–1250 μg/ml. Both aqueous extract (QGAE) and QGEAE could induce the morphological and structural changes of H. pylori, inhibit urease activity with IC50 of 1093 μg/ml and 332.90 μg/ml, respectively, and down-regulate the virulence genes, such as vacA and cagA. Conclusions QG may exhibit in vitro anti-H. pylori activity by inhibiting growth, destroying the bacterial structure and down-regulating the expression of virulence factors. Moreover, QG is the homology of food and TCM, which can be considered as a safe and convenient agent against H. pylori infection.

Magnetotactic multicellular prokaryotes (MMPs) consist of unique microorganisms formed by genetically identical Gram-negative bacterial that live as a single individual capable of producing magnetic nanoparticles called magnetosomes. Two distinct morphotypes of MMPs are known: spherical MMPs (sMMPs) and ellipsoidal MMPs (eMMPs). sMMPs have been extensively characterized, but less information exists for eMMPs. Here, we report the ultrastructure and organization as well as gene clusters responsible for magnetosome and flagella biosynthesis in the magnetite magnetosome producer eMMP Candidatus Magnetananas rongchenensis. Transmission electron microscopy and focused ion beam scanning electron microscopy (FIB-SEM) 3D reconstruction reveal that cells with a conspicuous core-periphery polarity were organized around a central space. Magnetosomes were organized in multiple chains aligned along the periphery of each cell. In the partially sequenced genome, magnetite-related mamAB gene and mad gene clusters were identified. Two cell morphologies were detected: irregular elliptical conical ` frustum-like' (IECF) cells and H-shaped cells. IECF cells merge to form H-shaped cells indicating a more complex structure and possibly a distinct evolutionary position of eMMPs when compared with sMMPs considering multicellularity.

Magnetotactic bacteria (MTB) are a group of phylogenetically and physiologically diverse Gram-negative bacteria that synthesize intracellular magnetic crystals named magnetosomes. MTB are affiliated with three classes of Proteobacteria phylum, Nitrospirae phylum, Omnitrophica phylum and probably with the candidate phylum Latescibacteria. The evolutionary origin and physiological diversity of MTB compared with other bacterial taxonomic groups remain to be illustrated. Here, we analysed the genome of the marine magneto-ovoid strain MO-1 and found that it is closely related to Magnetococcus marinus MC-1. Detailed analyses of the ribosomal proteins and whole proteomes of 390 genomes reveal that, among the Proteobacteria analysed, only MO-1 and MC-1 have coding sequences (CDSs) with a similarly high proportion of origins from Alphaproteobacteria, Betaproteobacteria, Deltaproteobacteria and Gammaproteobacteria. Interestingly, a comparative metabolic network analysis with anoxic network enzymes from sequenced MTB and non-MTB successfully allows the eventual prediction of an organism with a metabolic profile compatible for magnetosome production. Altogether, our genomic analysis reveals multiple origins of MO-1 and M. marinus MC-1 genomes and suggests a metabolism-restriction model for explaining whether a bacterium could become an MTB upon acquisition of magnetosome encoding genes.

Aloe vera has been widely used in cosmetics and as a health product. Although increasing research has indicated that chronic use of Aloe vera is closely associated with the development of colorectal cancer, the material basis and molecular mechanism of the pathogenesis have not been elucidated. The wnt/β-catenin signaling pathway plays an important role in the development of colorectal cancer. It should be useful to investigate whether Aloe vera has any impact on the wnt/β-catenin signaling pathway. In this study, we found that a water extract of Aloe vera at low concentration (0.98–12.50 μg ml−1) could activate the wnt/β-catenin signaling pathway in the presence of wnt3a ligand and up-regulated the level of active β-catenin protein in hek293 cells, as well as promoting the expression of wnt target genes (Axin2, DKK1, FGF20). Additionally, aloin and aloesin were the effective components interacting with other non-active ingredients in the water extract of Aloe vera that were identified by a knockout/knockin method with high-speed counter current chromatography (HSCCC). Meanwhile, no effects of the water extract of Aloe vera and aloin on the wnt/β-catenin signaling pathway were found, either in the presence or absence of other activators such as activator CHIR99021. In conclusion, the water extract of Aloe vera could activate the wnt/β-catenin signaling pathway in the presence of wnt3a and the effective components were aloin and aloesin. These findings might facilitate the understanding of the material basis and molecular mechanisms of Aloe vera in causing colorectal cancer.

GaN power transistors are well suited in high frequency, high temperature and high power-density applications. This paper investigates different gate driver designs for GaN power transistors, including fundamental driving concerns, current commercial products, popular gate driving features, and design trends for the suppression of gate node ringing. Many smart gate drivers offer features such as intelligent on-chip CPU for flexible digital control, adjustable gate voltage levels, multi-stage driving speed for slew-rate control, precise timing control, current sensing capability for close-loop regulations, and active gate driving mode with continuous optimized dead-time. This paper provides an overview to modern gate driver design trends and challenges for GaN power transistors.

In an effort to understand the molecular events contributing to the cytotoxicity activity of resveratrol (RSV), we investigated its effects on human lung adenocarcinoma epithelial cell line A549 at different concentrations. Cellular nucleoside metabolic profiling was determined by an established liquid chromatography-mass spectrometry method in A549 cells. RSV resulted in significant decreases and imbalances of deoxyribonucleoside triphosphates (dNTPs) pools suppressing subsequent DNA synthesis. Meanwhile, RSV at high concentration caused significant cell cycle arrest at S phase, in which cells required the highest dNTPs supply than other phases for DNA replication. The inhibition of DNA synthesis thus blocked subsequent progression through S phase in A549 cells, which may partly contribute to the cytotoxicity effect of RSV. However, hydroxyurea (HU), an inhibitor of RNR activity, caused similar dNTPs perturbation but no S phase arrest, finally no cytotoxicity effect. Therefore, we believed that the dual effect of high concentration RSV, including S phase arrest and DNA synthesis inhibition, was required for its cytotoxicity effect on A549 cells. In summary, our results provided important clues to the molecular basis for the anticancer effect of RSV on epithelial cells.

Detection of reverse-conduction in GaN-based switched-mode power converters is essential to reduce power loss and to protect the circuit from severe undershoot voltage. In this paper, an active clamping SenseFET circuit is proposed to measure the duration that the low-side GaN HEMT is in reverse-conduction and with protection from the high voltage at the switching node. The output of the SenseFET clamping circuit is processed by a custom designed gate driver IC. This IC is fabricated using TSMC's $0.18\ \boldsymbol{\mu} \mathbf{m}$ BCD GEN2 process for driving e-mode GaN power HEMTs with an on-chip closed-loop dead-time correction circuit. The one-step correction mode can optimize the dead-times for both the turn-on and turn-off edges in one switching cycle for switching frequencies of up to 10 MHz with 0.32 ns precision. This allow the power converters to maintain optimal conversion efficiency over the full output current range.

Tuberculosis (TB) is a continuing major threat to global health and a leading cause of death, particularly in developing countries. In this study, we aimed to identify a specific and sensitive diagnostic biomarker and develop a vaccine to prevent this disease. We investigated membrane proteins to reveal biomarkers in serum and peripheral blood mononuclear cells (PBMCs) obtained from TB patients. We employed Western blotting to evaluate serological immunoglobulin G levels, and Enzyme Linked Immunospot (ELISpot) to assess the antigen-specific cellular interferon-γ secretion from PBMCs after membrane protein stimulation. A total of 219 membrane proteins were identified, 52 exhibited at a higher levels than the 38-kDa prositive control. Of these 18 exhibited reacted ratios above 1, especially Rv1111c (427–981), with a ratios at 3.38. Accuracy and sensitivity were markedly higher for the top two antigen candidates, Rv0232 and Rv1115, after two rounds of ELISpot tests than ESAT-6 in the commercial kit (42.15 and 43.62%, respectively). These two proteins were administered to mice to detect whether they acted as effective antigens in vivo. These data provide a comprehensive view of the membranes involved in humoural and cellular immune responses that may be used as biomarkers for TB and candidates for a vaccine.

Many compounds of ginsenosides show anti-inflammatory properties. However, their anti-inflammatory effects in intervertebral chondrocytes in the presence of inflammatory factors have never been shown. Increased levels of pro-inflammatory cytokines are generally associated with the degradation and death of chondrocytes; therefore, finding an effective and nontoxic substance that attenuates the inflammation is worthwhile. In this study, chondrocytes were isolated from the nucleus pulposus tissues, and the cells were treated with ginsenoside compounds and IL-1β, alone and in combination. Cell viability and death rate were assessed by CCK-8 and flow cytometry methods, respectively. PCR, western blot, and immunoprecipitation assays were performed to determine the mRNA and protein expression, and the interactions between proteins, respectively. Monomeric component of ginsenoside Rd had no toxicity at the tested range of concentrations. Furthermore, Rd suppressed the inflammatory response of chondrocytes to interleukin (IL)-1β by suppressing the increase in IL-1β, tumor necrosis factor (TNF)-α, IL-6, COX-2, and inducible nitric oxide synthase (iNOS) expression, and retarding IL-1β-induced degradation of chondrocytes by improving cell proliferation characteristics and expression of aggrecan and COL2A1. These protective effects of Rd were associated with ubiquitination of IL-1 receptor accessory protein (IL1RAP), blocking the stimulation of IL-1β to NF-κB. Bioinformatics analysis showed that NEDD4, CBL, CBLB, CBLC, and ITCH most likely target IL1RAP. Rd increased intracellular ITCH level and the amount of ITCH attaching to IL1RAP. Thus, IL1RAP ubiquitination promoted by Rd is likely to occur by up-regulation of ITCH. In summary, Rd inhibited IL-1β-induced inflammation and degradation of intervertebral disc chondrocytes by increasing IL1RAP ubiquitination.

Magnetosome synthesis ability of Magnetospirillum gryphiswaldense MSR-1 in an autofermentor can be precisely controlled through strict control of dissolved oxygen concentration. In this study, using transcriptome data we discovered gene transcriptional differences and compared physiological characteristics of MSR-1 cells cultured under aerobic (high-oxygen) and micro-aerobic (low-oxygen) conditions. The results showed that 77 genes were up-regulated and 95 genes were down-regulated significantly under micro-aerobic situation. These genes were involved primarily in the categories of cell metabolism, transport, regulation and unknown-function proteins. The nutrient transport and physiological metabolism were slowed down under micro-aerobic condition, whereas dissimilatory denitrification pathways were activated and it may supplemental energy was made available for magnetosome synthesis. The result suggested that the genes of magnetosome membrane proteins (Mam and Mms) are not directly regulated by oxygen level, or are constitutively expressed. A proposed regulatory network of differentially expressed genes reflects the complexity of physiological metabolism in MSR-1, and suggests that some yet-unknown functional proteins play important roles such as ferric iron uptake and transport during magnetosome synthesis. The transcriptome data provides a holistic view of the responses of MSR-1 cells to differing oxygen levels. This approach will give new insights into general principles of magnetosome formation.

International audience; Bacteria of the genus Photobacterium thrive worldwide in oceans and show substantial eco-physiological diversity including free-living, symbiotic and piezophilic life styles. Genomic characteristics underlying this variability across species are poorly understood. Here we carried out genomic and physiological analysis of Photobacterium phosphoreum strain ANT-2200, the first deep-sea luminous bacterium of which the genome has been sequenced. Using optical mapping we updated the genomic data and reassembled it into two chromosomes and a large plasmid. Genomic analysis revealed a versatile energy metabolic potential and physiological analysis confirmed its growth capacity by deriving energy from fermentation of glucose or maltose, by respiration with formate as electron donor and trimethlyamine N-oxide (TMAO), nitrate or fumarate as electron acceptors, or by chemo-organo-heterotrophic growth in rich media. Despite that it was isolated at a site with saturated dissolved oxygen, the ANT-2200 strain possesses four gene clusters coding for typical anaerobic enzymes, the TMAO reductases. Elevated hydrostatic pressure enhances the TMAO reductase activity, mainly due to the increase of isoenzyme TorA1. The high copy number of the TMAO reductase isoenzymes and pressure-enhanced activity might imply a strategy developed by bacteria to adapt to deep-sea habitats where the instant TMAO availability may increase with depth.

SHANK2 is a scaffold protein that serves as a protein anchor at the postsynaptic density in neurons. Genetic variants of SHANK2 are strongly associated with synaptic dysfunction and the pathophysiology of autism spectrum disorder. Recent studies indicate that early neuronal developmental defects play a role in the pathogenesis of autism spectrum disorder, and that insulin-like growth factor 1 has a positive effect on neurite development. To investigate the effects of SHANK2 knockdown on early neuronal development, we generated a sparse culture system using human induced pluripotent stem cells, which then differentiated into neural progenitor cells after 3–14 days in culture, and which were dissociated into single neurons. Neurons in the experimental group were infected with shSHANK2 lentivirus carrying a red fluorescent protein reporter (shSHANK2 group). Control neurons were infected with scrambled shControl lentivirus carrying a red fluorescent protein reporter (shControl group). Neuronal somata and neurites were reconstructed based on the lentiviral red fluorescent protein signal. Developmental dendritic and motility changes in VGLUT1+ glutamatergic neurons and TH+ dopaminergic neurons were then evaluated in both groups. Compared with shControl VGLUT1+ neurons, the dendritic length and arborizations of shSHANK2 VGLUT1+ neurons were shorter and fewer, while cell soma speed was higher. Furthermore, dendritic length and arborization were significantly increased after insulin-like growth factor 1 treatment of shSHANK2 neurons, while cell soma speed remained unaffected. These results suggest that insulin-like growth factor 1 can rescue morphological defects, but not the change in neuronal motility. Collectively, our findings demonstrate that SHANK2 deficiency perturbs early neuronal development, and that IGF1 can partially rescue the neuronal defects caused by SHANK2 knockdown. All experimental procedures and protocols were approved by the Laboratory Animal Ethics Committee of Jinan University, China (approval No. 20170228010) on February 28, 2017.

Investigation into intracellular ribonucleotides (RNs) and deoxyribonucleotides (dRNs) is important for studies of the mechanism of many biological processes, such as RNA and DNA synthesis and DNA repair, as well as metabolic and therapeutic efficacy of nucleoside analogues. However, current methods are still unsatisfactory for determination of nucleotides in complex matrixes. Here we describe a novel method for the determination of RN and dRN pools in cells based on fast derivatization with (trimethylsilyl)diazomethane (TMSD) followed by quantification using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Derivatization was accomplished in 3 min, and each derivatized nucleotide not only had a sufficient retention on reversed-phase column by introduction of methyl groups but also exhibited a unique ion transition which consequently eliminated mutual interference in LC-MS/MS. Chromatographic separation was performed on a C18 column with a simple acetonitrile-water gradient elution system, which avoided contamination and ion suppression caused by ion-pairing reagents. The developed method was fully validated and applied to the analysis of RNs and dRNs in cell samples. Moreover, results demonstrated that the applicability of this method could be extended to nucleoside analogues and their metabolites and could facilitate many applications in future studies.

N type silicon-rich nanocrystalline-SiN(x) ∶ H films were prepared by plasma enhanced chemical vapor deposition technique by changing NH3 flow rate. The effect of nitrogen incorporation on the microstructure and photoelectric properties of the thin films were characterized by Raman, Fourier transform infrared spectroscopy, ultraviolet-visible absorption spectra, and Hall effect measurement. The results indicated that with the increasing NH3, a phase transition from microcrystalline to amorphous silicon occured. Transmission electron microscope observation revealed that the size of silicon quantum dots could be adjusted by varying the flow rate of NH3. The microstructure order of the films reduced with increasing the flow rate of NH3, while the optical band gap increased, and the optical band tail became narrow. Meanwhile, Si—N bonds density increased and P doping was blocked. I-V testing results showed that with increasing NH3, the conductivity of films first decreased compared with nanocrystalline-Si and then increased. These behaviors reveal a competition in the mechanisms controlling the conductivity. However, with further increasing NH3, the conductivity decreased significantly due to rapid carrier recombination on the amorphous net structure.

Gallium nitride (GaN) power transistors are gaining rapid acceptance by the power electronics industry as the next generation wide bandgap (WBG) power semiconductor technology. Early direct drop-in replacement attempts of the silicon based power MOSFETs with GaN power devices either produce no significant performance improvement or even degradation in some situations. This is mainly due to the fact that the GaN power devices were not driven properly to fully exploit their true performance. In this paper, different gate driving techniques for both depletion and enhancement mode GaN power transistors are examined. In addition, the recent trends on integrated GaN pre-driver and GaN power ICs is also discussed.

In this paper, an integrated smart gate driver IC with segmented output stage topology, programmable sense-FET, current sensing circuits and an on-chip stacked-based CPU for flexible digital control is presented. This IC is fabricated using TSMC's 0.18 μm BCD GEN2 process for driving a d-mode GaN power HEMT in cascode configuration. Using a segmentation technique, this IC can dynamically adjust the gate driving strength during switching transition to achieve slope control and EMI reduction. Programmable sense-FET and current sensing circuit monitor the load current for peak-current regulation. The embedded CPU can update all digital configuration bits on-the-fly. In dynamic driving mode, current spike at turn-on transition is reduced by 83% without sacrificing the switching speed. Current sensing circuit can detect peak current value and response within 5 ns. The pre-stored driving patterns can be loaded to the driving circuit in 1 μs under active driving mode.

To detect Japanese encephalitis virus (JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction (RT-PCR) detection system was developed.By aligning the full-length sequences of JEV (G1-G5), six sets of highly specific TaqMan real-time RT-PCR primers and probes were designed based on the highly conserved NS1, NS2, and M genes of JEV, which included one set for non-specific JEV detection and five sets for the detection of specific JEV genotypes. Twenty batches of mosquito samples were used to evaluate our quantitative PCR assay.With the specific assay, no other flavivirus were detected. The lower limits of detection of the system were 1 pfu/mL for JEV titers and 100 RNA copies/µL. The coefficients of variation of this real-time RT-PCR were all2.8%. The amplification efficiency of this method was between 90% and 103%.A TaqMan real-time RT-PCR detection system was successfully established to detect and differentiate all five JEV genotypes.

H7N9 was a cause of significant global health concern due to its severe infection and approximately 35% mortality in humans. By screening a Fab antibody phage library derived from patients who recovered from H7N9 infections, we characterized two human monoclonal antibodies (HuMAbs), HNIgGD5 and HNIgGH8. The epitope of these two antibodies was dependent on two residues in the receptor binding site at positions V186 and L226 of the hemagglutinin glycoprotein. Both antibodies possessed high neutralizing activity.

Seamounts are undersea mountains rising abruptly from the sea floor and interacting dynamically with underwater currents. They represent unique biological habitats with various microbial community structures. Certain seamount bacteria form conspicuous extracellular iron oxide structures, including encrusted stalks, flattened bifurcating tubes, and filamentous sheaths. To extend our knowledge of seamount ecosystems, we performed an integrated study on population structure and the occurrence of magnetotactic bacteria (MTB) that synthesize intracellular iron oxide nanocrystals in sediments of a seamount in the Mariana volcanic arc. We found Proteobacteria dominant at 13 of 14 stations, but ranked second in abundance to members of the phylum Firmicutes at the deep-water station located on a steep slope facing the Mariana-Yap Trench. Live MTB dwell in biogenic sediments from all 14 stations ranging in depth from 238 to 2,023 m. Some magnetotactic cocci possess the most complex flagellar apparatus yet reported; 19 flagella are arranged in a 3:4:5:4:3 array within a flagellar bundle. Phylogenetic analysis of 16S rRNA gene sequences identified 16 novel species of MTB specific to this seamount. Together the results obtained indicate that geographic properties of the seamount stations are important in shaping the bacterial community structure and the MTB composition.

High hydrostatic pressure (HHP) exerts severe effects on cellular processes including impaired cell division, abolished motility and affected enzymatic activities. Transcriptomic and proteomic analyses showed that bacteria switch the expression of genes involved in multiple energy metabolism pathways to cope with HHP. We sought evidence of a changing bacterial metabolism by supplying appropriate substrates that might have beneficial effects on the bacterial lifestyle at elevated pressure. We isolated a piezosensitive marine bacterium Vibrio fluvialis strain QY27 from the South China Sea. When trimethylamine N-oxide (TMAO) was used as an electron acceptor for energy metabolism, QY27 exhibited a piezophilic-like phenotype with an optimal growth at 30 MPa. Raman spectrometry and biochemistry analyses revealed that both the efficiency of the TMAO metabolism and the activity of the TMAO reductase increased under high pressure conditions. Among the two genes coding for TMAO reductase catalytic subunits, the expression level and enzymatic activity of TorA was up-regulated by elevated pressure. Furthermore, a genetic interference assay with the CRISPR-dCas9 system demonstrated that TorA is essential for underpinning the improved pressure tolerance of QY27. We extended the study to Vibrio fluvialis type strain ATCC33809 and observed the same phenotype of TMAO-metabolism improved the pressure tolerance. These results provide compelling evidence for the determinant role of metabolism in the adaption of bacteria to the deep-sea ecosystems with HHP.

The absolute and relative pool sizes of deoxyribonucleotides (dRNs) are essential in DNA replication fidelity, DNA damage and repair. We found in this study that although DNA damage induced by methyl methanesulfonate (MMS) seemed similar in cancer (HepG2) and normal (LO2) cells, more extensive alterations in ribonucleotides (RNs) and dRNs pools occurred in HepG2 cells indicating that HepG2 cells were more vigilant to DNA damage. After 10 h repair, RNs pools were still severely perturbed in LO2 cells. Compared to LO2 cells, deoxyribonucleotide triphosphates (dNTPs) pools in HepG2 cells elevated by more folds which could facilitate more efficient DNA repair and improve survival probability following DNA damage, although this should definitely lead to higher mutation rates. DNA repair was more efficient in HepG2 cells at S phase and it partly came to an end while DNA repair was still uncompleted in LO2 cells outside S phase. In conclusion, our results demonstrated that HepG2 and LO2 cells presented many differences in nucleotide metabolism, cell cycle checkpoints and DNA repair pathways in response to DNA damage, which could be potential targets for cancer treatment.

In this paper, an IGBT gate driver IC with a collector current sensing circuit and an on-chip CPU for digital control is presented. The IC is fabricated using TSMC's 0.18 μm BCD Gen-2 process. This technique is based on the unique Miller plateau relationship between the gate current and collector current (I g and I C ) for a particular gate resistance (R g ), and allows for a cycle by cycle measurement of I C during both turn-on and turn-off transients. Together with a dedicated and simple on-chip stack-based CPU, this technique can potentially provide collector current regulation without any extra discrete component. This technique only monitors the low voltage signal at the gate terminal, without the need to handle any high voltage signal on the collector/load side. Measurements have been carried out using a double pulse test setup. An accuracy within ±1 A is achieved over the current ranges between 1 to 30 A for turn-on and 1 to 50 A for turn-off.

Magnetococcus massalia strain MO-1 represents a group of fast-swimming marine magnetotactic coccoid-ovoid bacteria. They show polar magnetotaxis behavior in uniform magnetic field. MO-1 cells swim forward constantly with rare stop. When they meet obstacles, MO-1 cells could squeeze through or circumvent the obstacles. Here, we describe the methods for characterization of magnetotactic behaviors of MO-1 cells using adapted spectrophotometer and microscope mounted with magnetic fields.