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Purpose This paper aims to propose a low-power complementary MOS (CMOS) current sensor for control circuit in an integrated DC-DC buck converter. Design/methodology/approach The integrated DC-DC converter, which is composed of feedback control circuit and power block, is designed with 0.35-µm CMOS process. Current sensor in the control circuit is integrated with sense-FET and voltage-follower circuits to reduce power consumption and improve its sensing accuracy. In the current-sensing circuit, the size ratio of the power metal oxide semiconductor field effect transistor (MOSFET) to the sensing transistor (K) is 1,000, and a current-mirror is used for a voltage follower. N-channel MOS acts as a switching device in the current-sensing circuit, where the sensing FET is in parallel with the power MOSFET. The amplifier and comparator are designed to obtain a high gain and a fast transient time. Findings Experiment shows that the current sensor is operated with accuracy of more than 85 per cent, and the transient time of the error amplifier is controlled within 100 µs. The sensing current is in the range of a few hundred µA at a frequency of 0.6-2 MHz and an input voltage of 3-5 V. The output voltage is obtained as expected with the ripple ratio within 5 per cent. Originality/value The proposed current sensor in DC-DC converter provides an accurately sensed inductor current with a significant reduction in power consumption in the range of 0.2 mW. High-accuracy regulation is obtained using the proposed current sensor. As the sensor utilizes simple switch-type voltage follower and sense-FET, it can be widely applied to other low-power applications such as high-frequency oscillator and over-current protection circuit.

The organocatalytic enantioselective conjugate reaction of 2-fluoro-1,3-diketones to nitroalkenes promoted by chiral binaphthyl-modified squaramide has been achieved. Treatment of 2-fluoro-1,3-diketones with nitroalkenes under mild reaction conditions afforded the corresponding Michael products containing fluorinated quaternary carbon stereocenter with excellent enantioselectivity (up to 98% ee).

A novel species of the genus Arenimonas, represented by strain S2-21T, was isolated from an estuary of Asan in South Korea. Cells of strain S2-21T were Gram-stain-negative, aerobic, non-motile rods that were oxidase- and catalase-positive. Growth of strain S2-21T was observed at 15–40 °C (optimum, 25–30 °C), at pH 7.0–8.0 (optimum, pH 7.0) and in the presence of 0–2.0 % (w/v) NaCl (optimum, 0 %). The major cellular fatty acids were iso-C15 : 0, C11 : 0 3-OH, iso-C16 : 0, summed feature 9 (comprising iso-C17 : 1ω9c and/or C16 : 0 10-methyl), anteiso-C17 : 0 and iso-C11 : 0. The only respiratory quinone detected was ubiquinone-8 (Q-8) and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmethylethanol and two unknown phospholipids. The G+C content of the genomic DNA was 62.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S2-21T formed a tight phyletic lineage with Arenimonas donghaensis HO3-R19T within the genus Arenimonas. Strain S2-21T was related most closely to A. donghaensis HO3-R19T at 98.1 % 16S rRNA gene sequence similarity and the mean DNA–DNA relatedness value between strain S2-21T and the type strain of A. donghaensis was 23.6 ± 2.2 %. On the basis of phenotypic, chemotaxonomic and molecular features, strain S2-21T is considered to represent a novel species of the genus Arenimonas, for which the name Arenimonas aestuarii sp. nov. is proposed. The type strain is S2-21T ( = KACC 18504T = JCM 31129T).

Attention-deficit/hyperactivity disorder (ADHD) patients show learning difficulty and impulsiveness. Exercise is known to improve learning ability and memory function. In the present study, we investigated the duration-dependence of the effect of treadmill exercise on spatial learning ability in relation with brain-derived neurotrophic factor (BDNF) expression in ADHD rats. For this study, radial 8-arm maze test and western blot for BDNF and tyrosine kinase B (TrkB) were performed. Spontaneous hypertensive rats were used as the ADHD rats and Wistar-Kyoto rats were used as the control rats. The rats in the exercise groups were forced to run on a treadmill for 10 min, 30 min, and 60 min once a day for 28 consecutive days. ADHD rats displayed impairment of spatial learning ability, in contrast treadmill exercise ameliorated impairment of spatial learning ability. Treadmill exercise for 30 min per day showed most potent ameliorating effect on impairment of spatial learning ability. BDNF and TrkB expressions in the hippocampus were decreased in the ADHD rats, in contrast treadmill exercise enhanced BDNF and TrkB expressions. Treadmill exercise for 30 min and for 60 min per day showed enhancing effects on BDNF and TrkB expressions. Treadmill exercise alleviated deficits in the spatial learning ability through enhancing BDNF and TrkB expressions in the ADHD rats. Treadmill exercise for 30 min per day can be considered as the most effective therapeutic modality for the ADHD symptoms.

In this paper, an integrated low-voltage control circuit is introduced for a charge pump DC-DC boost converter. By exploiting the advantage of the integration of the feedback control circuit within CMOS technology, the charge pump boost converter offers a low-current operation with small ripple voltage. The error amplifier, comparator, and oscillator in the control circuit are designed with the supply voltage of 3.3 V and the operating frequency of 1.6~5.5 MHz. The charge pump converter with the 4 or 8 pump stages is measured in simulation. The test in the 0.35 μm CMOS process shows that the load current and ripple ratio are controlled under 1 mA and 2% respectively. The output-voltage is obtained from 4.8 ~ 8.5 V with the supply voltage of 3.3 V.

A low power CMOS control circuit is applied in an integrated DC-DC buck converter. The integrated converter is composed of a feedback control circuit and power block with 0.35 μm CMOS process. A current-sensing circuit is integrated with the sense-FET method in the control circuit. In the current-sensing circuit, a current-mirror is used for a voltage follower in order to reduce power consumption with a smaller chip-size. The N-channel MOS acts as a switching device in the current-sensing circuit where the sensing FET is in parallel with the power MOSFET. The amplifier and comparator are designed to obtain a high gain and a fast transient time. The converter offers well- controlled output and accurately sensed inductor current. Simulation work shows that the current-sensing circuit is operated with an accuracy of higher than 90% and the transient time of the error amplifier is controlled within 75 μsec. The sensing current is in the range of a few hundred μA at a frequency of 0.6~2 MHz and an input voltage of 3~5 V. The output voltage is obtained as expected with the ripple ratio within 1%.

Sphingorhabdus sp. M41, capable of degrading aliphatic and aromatic hydrocarbons, was isolated from crude oil-contaminated costal sediment by an enrichment culture and its complete genome was sequenced. The genome of strain M41 has a chromosome with a size of 3,324,420bp, including 44 tRNAs, 6 rRNAs, and 3118 protein-coding genes. In addition, many potential genes responsible for the biodegradation of aliphatic and aromatic hydrocarbons were identified from the genome. This is the first complete genome of the genus Sphingorhabdus, which will provide insights into the bioremediation of crude oil-contaminated costal sediment by strain M41.

Zhongshania aliphaticivorans SM-2(T), a degrader of aliphatic hydrocarbons, is a Gram-negative, rod-shaped, flagellated, facultatively aerobic bacterium. Here, we report the genome sequence of strain SM-2(T), which has a size of 4,204,359bp with 44 tRNAs, 9 rRNAs, and 3664 protein-coding genes. In addition, several genes encoding aliphatic hydrocarbon degraders (alkane 1-monooxygenase, haloalkane dehalogenase, and cytochrome P450) were detected in the genome shedding light on the function of pollutants degradation.

A Gram-staining-negative, moderately halophilic and strictly aerobic bacterium, designated strain KJ4T, was isolated from marine sediment at Gangjin in South Korea. Cells were catalase- and oxidase-positive long rods with gliding motility. Growth of strain KJ4T was observed at 4–37 °C (optimum, 15–25 °C), at pH 6.0–9.0 (optimum, pH 7.0–8.5) and in the presence of 1.0–7.0 % (w/v) NaCl (optimum, 2.0–5.0 %). Menaquinone 6 (MK-6) was the only isoprenoid quinone detected and iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c) were the major cellular fatty acids. The polar lipids of strain KJ4T consisted of phosphatidylethanolamine, an unidentified aminophospholipid and five unidentified lipids. The G+C content of the genomic DNA was 38.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KJ4T formed a distinct phylogenetic lineage within the genus Maribacter. Strain KJ4T was most closely related to Maribacter orientalis KMM 3947T with 97.4 % 16S rRNA gene sequence similarity. On the basis of phenotypic, chemotaxonomic and molecular features, strain KJ4T clearly represents a novel species of the genus Maribacter, for which the name Maribacter lutimaris sp. nov. is proposed. The type strain is KJ4T ( = KACC 16438T = JCM 31154T).

A genome-wide transcriptional analysis of Alteromonas naphthalenivorans SN2 was performed to investigate its ecophysiological behavior in contaminated tidal flats and seawater. The experimental design mimicked these habitats that either added naphthalene or pyruvate; tidal flat-naphthalene (TF-N), tidal flat-pyruvate (TF-P), seawater-naphthalene (SW-N), and seawater-pyruvate (SW-P). The transcriptional profiles clustered by habitat (TF-N/TF-P and SW-N/SW-P), rather than carbon source, suggesting that the former may exert a greater influence on genome-wide expression in strain SN2 than the latter. Metabolic mapping of cDNA reads from strain SN2 based on KEGG pathway showed that metabolic and regulatory genes associated with energy metabolism, translation, and cell motility were highly expressed in all four test conditions, probably highlighting the copiotrophic properties of strain SN2 as an opportunistic marine r-strategist. Differential gene expression analysis revealed that strain SN2 displayed specific cellular responses to environmental variables (tidal flat, seawater, naphthalene, and pyruvate) and exhibited certain ecological fitness traits –– its notable PAH degradation capability in seasonally cold tidal flat might be reflected in elevated expression of stress response and chaperone proteins, while fast growth in nitrogen-deficient and aerobic seawater probably correlated with high expression of glutamine synthetase, enzymes utilizing nitrite/nitrate, and those involved in the removal of reactive oxygen species.

A Gram-staining-negative, aerobic and moderately halophilic bacterium, designated strain NS6T, was isolated from sea-tidal-flat sediment of the South Sea in Korea. Cells were motile rods with a single flagellum showing positive catalase and oxidase activities. Strain NS6Tgrew at 15–40 °C (optimum, 30 °C), at pH 6.0–9.0 (optimum, pH 7.0–7.5) and in the presence of 1–5 % (w/v) NaCl (optimum, 2 %). Ubiquinone-10 was identified as the only isoprenoid quinone and summed feature 8 (comprising C18 : 1ω7c/ω6c), C19 : 0cyclo ω8c, C16 : 0and C10 : 03-OH were the major fatty acids. Strain NS6Tcontained phosphatidylglycerol, sulfoquinovosyldiacylglycerol, an unidentified amino lipid and an unidentified lipid as the major polar lipids. An unidentified phospholipid and three unidentified lipids were also detected as the minor polar lipids. The G+C content of the genomic DNA was 64.5 mol%. Strain NS6Twas most closely related toConfluentimicrobium lipolyticumSSK1-4Twith a 96.8 % 16S rRNA gene sequence similarity, and the phylogenetic analysis based on 16S rRNA gene sequences showed that strain NS6Tformed a tight phylogenetic lineage withC. lipolyticumSSK1-4T. The physiological, chemotaxonomic and phylogenetic properties suggest that strain NS6Trepresents a novel species of the genusConfluentimicrobium, for which the nameConfluentimicrobium naphthalenivoranssp. nov. is proposed. The type strain is NS6T( = KCTC 18418T = JCM 30828T). An emended description of the genusConfluentimicrobiumis also proposed.

A Gram-stain-negative heterotrophic bacterium, designated GSD6T, capable of growth on aliphatic hydrocarbons as a sole carbon and energy source, was isolated from sea-tidal flat sediment of the Yellow Sea, South Korea. Cells were facultatively aerobic, catalase- and oxidase-positive, motile rods with a single polar flagellum. Growth of strain GSD6T was observed at 4–37 °C (optimum 30 °C), at pH 5.5–9.0 (optimum pH 6.5–7.5) and in the presence of 1–9 % (w/v) NaCl (optimum 2 %). Strain GSD6T contained ubiquinone-8 (Q-8) as the sole isoprenoid quinone and summed feature 3 (comprising C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0, C18 : 1ω7c, C17 : 0 10-methyl and C17 : 1ω8c as the major fatty acids. Phosphatidylethanolamine and phosphatidylglycerol were identified as the major polar lipids. The G+C content of the genomic DNA was 44.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GSD6T formed a phylogenetic lineage with members of the genus Aliiglaciecola . Strain GSD6T was most closely related to Aliiglaciecola lipolytica E3T with a 16S rRNA gene sequence similarity of 97.4 %, but their DNA–DNA hybridization value was 39.1±7.1 %. On the basis of phenotypic, chemotaxonomic and molecular features, strain GSD6T represents a novel species of the genus Aliiglaciecola , for which the name Aliiglaciecola aliphaticivorans sp. nov. is proposed. The type strain is GSD6T ( = KACC 18129T = JCM 30133T). An emended description of the genus Aliiglaciecola is also proposed.

In this paper, a high performance current mode logic (CML) frequency divider is introduced in an integrated CMOS phase-locked loop (PLL). Inductive peaking structure and cascode circuit are applied in the CML frequency divider to obtain the broad-band and high frequency operation. In order to obtain a stable operation with low power, the resistor in the inductive peaking structure is replaced by the cascode circuit. DC bias voltage is applied in MOS gate as a current source in the divider. The proposed frequency divider is applied in the conventional PLL which is integrated with 0.18 a#x03BC;m CMOS process. Simulation test shows that the 2:1 divider is operated at the input frequency of 20 GHz with the power consumption of 15 mW.

In this paper, the circuit for electromagnetic interface (EMI) reduction in liquid crystal display (LCD) is proposed. The segmented driver circuit and cascode level shifter are employed in the column driver IC for the EMI reduction. The proposed column driver IC reduces the switching peak current in LCD panel by adopting the segmented operation in data latch. It provides an oscillating transient current with significantly reduced peak currents. The column driver IC and clock controller are integrated in 0.35 μm CMOS technology with 1-poly and 4-metal process. The simulation test shows that the proposed column driver circuit for LCD driver IC significantly reduces EMI noise level by more than 15 dB with 20 segmented operation in data latch at 40 MHz frequency.

This paper proposes a charge pump that minimizes the current mismatch and keeps the constant current across a wide range of output voltage. The charge pump is a two-stage circuit which is composed of the conventional push-pull charge pump and the compensation circuit. The compensation circuit has a feedback biasing circuit and an op-amp to act as a voltage follower. The features of feedback circuit and voltage follower are the important elements to reduce the current mismatch. The proposed charge pump is applied in 2 GHz PLL to check out the noise spectrum of the spur and phase offset which are occurred from the current mismatch. The proposed charge pump indicates that the current mismatch is less than 5 % over the voltage range of 0.30 ~ 1.45 V which covers almost 63 % of the 1.8 V supply voltage. The spur in PLL is obtained to be -63.7 dBc, while the conventional charge pump provides the spur of -36.2 dBc in the same PLL.