Association of Six Single Nucleotide Polymorphisms with Gestational Diabetes Mellitus in a Chinese Population

To investigate whether the candidate genes that confer susceptibility to type 2 diabetes mellitus are also correlated with gestational diabetes mellitus (GDM) in pregnant Chinese women.In this study, 1764 unrelated pregnant women were recruited, of which 725 women had GDM and 1039 served as controls. Six single nucleotide polymorphisms (rs7754840 in CDKAL1, rs391300 in SRR, rs2383208 in CDKN2A/2B, rs4402960 in IGF2BP2, rs10830963 in MTNR1B, rs4607517 in GCK) were genotyped using TaqMan allelic discrimination assays. The genotype and allele distributions of each SNP between the GDM cases and controls and the combined effects of alleles for the risk of developing GDM were analyzed. We found that the rs4402960, rs2383208 and rs391300 were statistically associated with GDM (OR = 1.207, 95%CI = 1.029-1.417, p = 0.021; OR = 1.242, 95%CI = 1.077-1.432, p = 0.003; OR = 1.202, 95%CI = 1.020-1.416, P = 0.028, respectively). In addition, the effect was greater under a recessive model in rs391300 (OR = 1.820, 95%CI = 1.226-2.701, p = 0.003). Meanwhile, the joint effect of these three loci indicated an additive effect of multiple alleles on the risk of developing GDM with an OR of 1.196 per allele (p = 1.08×10(-4)). We also found that the risk alleles of rs2383208 (b = -0.085, p = 0.003), rs4402960 (b = -0.057, p = 0.046) and rs10830963 (b = -0.096, p = 0.001) were associated with HOMA-B, while rs7754840 was associated with decrease in insulin AUC during a 100 g OGTT given at the time of GDM diagnosis (b = -0.080, p = 0.007).Several risk alleles of type 2 diabetes were associated with GDM in pregnant Chinese women. The effects of these SNPs on GDM might be through the impairment of beta cell function and these risk loci contributed additively to the disease

An EMI Reduction Charge Pump With a Hybrid Modulation Technique for Motor Drive Applications in 0.18 um BCD Process

Reducing the impact of electromagnetic interference (EMI) on switching inverters is an essential part of improving the performance of motor drives. This paper proposed a charge pump circuit with a hybrid modulation method to reduce the EMI of motor drive chips. This innovative method uses a combination of coarse modulation and fine modulation. The periodic modulation technique is used as coarse modulation to alter the spread spectrum range, while the random modulation technique is used as fine modulation to slow down switching transitions by adjusting the delay of the oscillating signal edges. Additionally, a buffer circuit is proposed to restrict the charge and discharge current of the charge pump, thus reducing the EMI due to the rapid variation of the current peak. Theoretical analysis and MATLAB simulation have confirmed that the hybrid modulation method has a pronounced effect on reducing the EMI of the circuit. The proposed motor drive system has been designed and verified by a 0.18 $\mu {\mathrm{ m}}$ BCD process, and the test results show that the proposed circuit can reduce the EMI by up to 22.27 dB compared to the non-modulated circuit. The motor drive chip area is $0.173~mm^{2}$ , and the power consumption is 5.677 mW

Summary of Research on Related Technologies of Ship Dynamic Positioning System

Dynamic positioning means that the ship can resist the influence of wind, wave, current and other environmental interference through its own propeller without anchoring, so as to realize the maintenance of its fixed position or expected track on the sea surface, with the advantages of not limited by water depth, rapid input or evacuation, good mobility and accurate positioning. This paper briefly introduces the components, working principle and mathematical model of the ship dynamic positioning system; On this basis, this paper summarizes the research status of the control strategy, filtering and data fusion, thrust distribution method and other related technologies of the ship dynamic positioning system at home and abroad; Finally, the development trend of the above-mentioned related technologies is discussed, so as to provide reference for the research in this field

A 5 V-to-32 V Input PVT-Robust Charge-Pump Circuit with Adjustable Output in a 0.18 μm BCD Process

In this paper, a new closed-loop charge-pump circuit with adjustable output voltage and an on-chip compensation technique is proposed. The environmental temperature and process corner can be detected with an on-chip detection circuit and automatically feedback an adjusted reference voltage. With this, the magnitude of the charge-pump output voltage with Pulse-Width Modulation (PWM) can be compensated. The charge-pump circuit is designed and verified with a 180 nm Bipolar-CMOS-DMOS (BCD) process, and its output voltage at different process, voltage, and temperature (PVT) is controllable with low ripple. There are three selections for adjusting the output voltage: +5 V/+7 V/+10 V shifts, with the supply voltage ranging from 5 V to 32 V. It can remain tunable and stable at any shifts. The maximum deviation is ±0.265%, and the maximum load current can reach 30 mA. The ripple voltage is less than 0.3% (Δ Vripple/Vout) underthe maximum load. The Monte Carlo simulation results show that the worst case of the process sensitivity (σ/μ) is 0.1%. The charge-pump core area is 0.308 mm2, and the power consumption is 4.753 mW. The circuit can produce high-precision output and is suitable for high-side driving IC applications

Application of an Artificial Fish Swarm Algorithm in an Optimum Tuned Mass Damper Design for a Pedestrian Bridge

Tuned mass damper (TMD) has a wide application in the human-induced vibration control of pedestrian bridges and its parameters have great influence on the control effects, hence it should be well designed. A new optimization method for a TMD system is proposed in this paper, based on the artificial fish swarm algorithm (AFSA), and the primary structural damping is taken into consideration. The optimization goal is to minimize the maximum dynamic amplification factor of the primary structure under external harmonic excitations. As a result, the optimized TMD has a smaller maximum dynamic amplification factor and better robustness. The optimum TMD parameters for a damped primary structure with different damping ratios and different TMD mass ratios are summarized in a table for simple, practical design, and the fitting equation is also provided. The TMD configuration optimized by the proposed method was shown to be superior to that optimized by other classical optimization methods. Finally, the application of an optimized TMD based on AFSA for a pedestrian bridge is proposed as a case study. The results show that the TMD designed based on AFSA has a smaller maximum dynamic amplification factor than the TMD designed based on the classic Den Hartog method and the TMD designed based on the Ioi Toshihiro method, and the optimized TMD has a good effect in controlling human-induced vibrations at different frequencies

Study on Adaptive-Passive and Semi-Active Eddy Current Tuned Mass Damper with Variable Damping

Tuned mass damper (TMD) is a widely used vibration control device, consisting of a mass, some springs and damping elements. Viscous damper is mostly used as a damping element; however, it has many unsustainable problems, e.g., poor durability, sensitive to the change of temperature, difficult to adjust the damping, oil leakage etc. In this paper, a new sustainable adaptive-passive eddy current tuned mass damper (ECTMD) with variable damping, which is very easy to be further upgraded to a semi-active one, is proposed. Four important parameters, e.g., adsorption position of permanent magnets, thickness of the conductive plate, thickness of the extra steel plate and the air gap between permanent magnets and the conductive plate are investigated by a parametric study. Two new evaluation indexes are put forward to indicate the damping mechanism of the proposed device. The relationship between effective damping coefficient and air gap is fitted through a quadratic function. Then, the corresponding design method of the proposed adaptive–passive ECTMD is presented. At last, the previous adaptive–passive ECTMD is upgraded to a semi-active one, which can adjust its eddy current damping through adjusting its air gap in real-time, based on the linear-quadratic-Gaussian algorithm. The effectiveness of semi-active ECTMD is evaluated through harmonic excitations and human-induced excitations. The results show that the semi-active ECTMD with variable damping has a better vibration control effect than the optimized passive one

Altering the linker in processive GH5 endoglucanase 1 modulates lignin binding and catalytic properties

Abstract Background The non-productive adsorption of cellulases onto lignin in biomass is a key issue for the biofuel process economy. It would be helpful to reduce the inhibitory effect of lignin on enzymatic hydrolysis by engineering weak lignin-binding cellulases. Cellulase linkers are highly divergent in their lengths, compositions, and glycosylations. Numerous studies have revealed that linkers can facilitate optimal interactions between structured domains. Recently, efforts have focused on the contributions and mechanisms of carbohydrate-binding modules and catalytic domains that affect lignin affinity and processivity of cellulases, but our understanding of the effects of the linker regions on lignin adsorption and processivity of GH5 processive endoglucanases is still limited. Results Eight GH5 endoglucanase 1 variants of varying length, flexibility, and sequence in the linker region were constructed. Their characteristics were then compared to the wild-type enzyme (EG1). Remarkably, significant differences in the lignin adsorption profiles and processivities were observed for EG1 and other variants. Our studies suggest that either the length or the specific amino acid composition of the linker has a prominent influence on the lignin-binding affinity of the enzymes. Comparatively, the processivity may depend primarily on the length of the linker and less so on the specific amino acid composition. EG1-ApCel5A, a variant with better performance in enzymatic hydrolysis in the presence of lignin, was obtained by replacing a longer, flexible linker. In total, up to between 28.2 and 30.1% more reducing sugars were generated from filter paper by EG1-ApCel5A in the presence of lignin compared to EG1. Conclusions Our results highlight the relevance of the linker region in the lignin adsorption and processivity of a processive endoglucanase. Our findings suggest that the linker region may be used as a target for the design of more active and weaker lignin-binding cellulases

Comparison of the Biochemical Properties and Roles in the Xyloglucan-Rich Biomass Degradation of a GH74 Xyloglucanase and Its CBM-Deleted Variant from Thielavia terrestris

Xyloglucan is closely associated with cellulose and still retained with some modification in pretreated lignocellulose; however, its influence on lignocellulose biodegradation is less understood. TtGH74 from Thielavia terrestris displayed much higher catalytic activity than previously characterized fungal GH74 xyloglucanases. The carbohydrate-binding module 1 (CBM1) deleted variant (TtGH74ΔCBM) had the same optimum temperature and pH but an elevated thermostability. TtGH74 displayed a high binding affinity on xyloglucan and cellulose, while TtGH74ΔCBM completely lost the adsorption capability on cellulose. Their hydrolysis action alone or in combination with other glycoside hydrolases on the free xyloglucan, xyloglucan-coated phosphoric acid-swollen cellulose or pretreated corn bran and apple pomace was compared. CBM1 might not be essential for the hydrolysis of free xyloglucan but still effective for the associated xyloglucan to an extent. TtGH74 alone or synergistically acting with the CBH1/EG1 mixture was more effective in the hydrolysis of xyloglucan in corn bran, while TtGH74ΔCBM showed relatively higher catalytic activity on apple pomace, indicating that the role and significance of CBM1 are substrate-specific. The degrees of synergy for TtGH74 or TtGH74ΔCBM with the CBH1/EG1 mixture reached 1.22–2.02. The addition of GH10 xylanase in TtGH74 or the TtGH74ΔCBM/CBH1/EG1 mixture further improved the overall hydrolysis efficiency, and the degrees of synergy were up to 1.50–2.16

Insights into the capability of the lignocellulolytic enzymes of Penicillium parvum 4-14 to saccharify corn bran after alkaline hydrogen peroxide pretreatment

Abstract Background Corn bran is a major agro-industrial byproduct from corn starch processing. It contains abundant arabinoxylan that can be converted into value-added chemicals via biotechnology. Corn bran arabinoxylan (CBAX) is one of the most recalcitrant xylans for enzymatic degradation due to its particular heterogeneous nature. The present study aimed to investigate the capability of the filamentous fungus Penicillium parvum 4-14 to enzymatically saccharify CBAX and reveal the fungal carbohydrate-active enzyme (CAZyme) repertoire by genome sequencing and secretome analysis. Results CBAX1 and CBAX2 with different branching degrees, together with corn bran residue (CBR) were generated from corn bran after alkaline hydrogen peroxide (AHP) pretreatment and graded ethanol precipitation. The protein blends E_CBAX1, E_CBAX2, and E_CBR were produced by the fungus grown on CBAX1, CBAX2, or CBR, respectively. Under the optimal conditions, E_CBAX1 released more than 80% xylose and arabinose from CBAX1 and CBAX2. Almost complete saccharification of the arabinoxylans was achieved by combining E_CBAX1 and a commercial enzyme cocktail Cellic®CTec3. Approximately 89% glucose, 64% xylose, and 64% arabinose were liberated from CBR by E_CBR. The combination of E_CBR with Cellic®CTec3 enhanced the saccharification of CBR, with conversion ratios of 97% for glucose, 81% for xylose, and 76% for arabinose. A total of 376 CAZymes including plentiful lignocellulolytic enzymes were predicted in P. parvum based on the fungal genomic sequence (25.8 Mb). Proteomic analysis indicated that the expression of CAZymes in P. parvum varied between CBAX1 and CBR, and the fungus produced complete cellulases, numerous hemicellulases, as well as high levels of glycosidases under the culture conditions. Conclusions This investigation disclosed the CAZyme repertoire of P. parvum at the genomic and proteomic levels, and elaborated on the promising potential of fungal lignocellulolytic enzymes upon saccharification of corn bran biomass after AHP pretreatment

Antimicrobial and Antivirulence Activities of Carvacrol against Pathogenic Aeromonas hydrophila

Aeromonas hydrophila is a ubiquitous Gram-negative opportunistic pathogen in the freshwater environment and the most common cause of bacterial septicemia in aquaculture. In this study, we investigated the impact of carvacrol, a natural monoterpenoid found in herbs, on the virulence of A. hydrophila in vitro and the antibacterial effect in combination with antibiotics. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of carvacrol against A. hydrophila NJ-35 were 125 µg/mL and 250 µg/mL, respectively. Carvacrol could inhibit the virulence factors (biofilm, protease, exopolysaccharide, and hemolysin) of A. hydrophila, and the antibiofilm potential of carvacrol was further verified by microscopic detection. Transcriptional analyses showed that the gene expression of flaB, ompA, aha, ahp, ela, act, aerA, AhyR, and hly were marked as downregulated. The checkerboard assay results showed that carvacrol did not have an antagonistic effect in combination with antibiotics (florfenicol, enrofloxacin, thiamphenicol, or doxycycline hydrochloride) commonly used in aquaculture but possessed an additive-synergistic effect with neomycin sulfate. In vivo studies demonstrated that carvacrol protected grass carp (Ctenopharyngodon idella) from A. hydrophila infection. Our results indicated that carvacrol possessed significant anti-bacterial and anti-virulence effects on A. hydrophila