Study on the evaluation index system and evaluation method for self-elevating drilling unit design

In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis （GRA）, in which the analytic hierarchy process （AHP） was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms.

Mathematically modeling the main dimensions of self-elevating drilling units

The present status of self-elevating drilling units was analysed. Based on statistics of the main dimensions of self-elevating drilling units, a mathematical model was established using stepwise return procedures and a back-propagation neural network. mathematical model is applicable and reliable. The of the main dimensions of self-elevating drilling Analysis of examples of calculations showed that the model is useful for mastering the essential variations units and can be used for technical and economic analysis as well as in conceptual designs of drilling units.

Lowering ash slagging and fouling tendency of high-alkali coal by hydrothermal pretreatment

High-alkali species in coal are notorious for causing ash slagging and fouling incidents.In this paper,four high-alkali coals were individually subject to hydrothermal pretreatment(HTP),within a batch-type autoclave at 300 -C for 1 h,and the treated coals were analyzed,along with the oxygen-containing functional groups determined by Fourier transform infrared spectrometer(FT-IR).Then the alkali species and other components in the coal ash were quantified by X-ray fluorescence(XRF)for evaluating the ash slagging and fouling tendency.Apart from this,FactSage was adopted to simulate the occurrence and transformation of alkali species during coal thermal conversion ending at various temperatures.The findings indicate that the treated coals are superior to the parent ones in terms of certain remarkable changes via HTP.The moisture,oxygen and sulfur of the hydrothermally treated coals decline obviously,while the calorific value rises sharply.HTP could reduce the alkali species to less than 2%(%,by weight,equivalent to Na2O in dry ash),with a maximum removal ratio of 88.9%,lowering the ash slagging and fouling tendency.The proposed mechanism of HTP was that the alkali species in coal matrix became released due to the breakage of the coal functional groups and micropores during HTP.

Insulin plus incretin:A glucose-lowering strategy for type 2-diabetes

There are many advantages of combining incretin therapy[glucagon-like peptide-1(GLP-1)receptor agonists and dipeptidyl peptidase-4(DPP-4)inhibitors]with insulin therapy as a glucose-lowering strategy in type2 diabetes.One important advantage is the complementary mode of the mechanistic action of incretin and insulin therapy.Another advantage is the reduction in risk of hypoglycemia and weight gain when adding incretin therapy to insulin.Several clinical trials have studied the addition of GLP-1 receptor agonists[exenatide BID(twice daily),lixisenatide,albiglutide]or DPP-4inhibitors(vildagliptin,sitagliptin,saxagliptin,alogliptin,linagliptin)to ongoing insulin therapy or adding insulin to ongoing therapy with a GLP-1 receptor agonist(liraglutide).These studies show improved glycemia in the presence of limited risk for hypoglycemia and weight gain with the combination of incretin therapy with insulin.This article reviews the background and clinical studies on this combination.

Curcuminoids Target Decreasing Serum Adipocyte-fatty Acid Binding Protein Levels in Their Glucose-lowering Effect in Patients with Type 2 Diabetes

Whether supplementation of curcuminoids decreases serum adipocyte-fatty acid binding protein（A-FABP） level and whether this decrease benefits glucose control is unclear.One-hundred participants（n=50 administered curcuminoids,n=50 administered placebo） from our previous report on the effect of curcuminoids on type 2 diabetes in a 3-month intervention were assessed for levels of serum A-FABP,oxidative stress,and inflammatory biomarkers.Curcuminoids supplementation led to significant decreases in serum A-FABP,C-reactive protein（CRP）,tumor necrosis factor-α,and interleukin-6 levels.Curcuminoids supplementation also significantly increased serum superoxide dismutase（SOD） activity.The change in serum A-FABP levels showed positive correlations with changes in levels of glucose,free fatty acids（FFAs）,and CRP in subjects supplemented with curcuminoids.Further stepwise regression analysis showed that A-FABP was an independent predictor for levels of FFAs,SOD,and CRP.These results suggest that curcuminoids may exert anti-diabetic effects,at least in part,by reductions in serum A-FABP level.A-FABP reduction is associated with improved metabolic parameters in human type 2 diabetes.

Dynamic Stress Analysis of the Leg Joints of Self-Elevating Platform

Since a self-elevating platform often works in water for a long time, the lattice leg is largely influenced by wave and current. The amplitude of leg joint stresses is a very important factor for the fatigue life of the platform. However, there are not many researches having been done on the mechanism and dynamic stress analysis of these leg joints. This paper focuses on the dynamic stress analysis and suppression methods of the leg joints of self-elevating platforms. Firstly, the dynamic stresses of the lattice leg joints are analyzed for a self-elevating platform by use of the 5th-order Stokes wave theory. Secondly, the axial and bending stresses are studied due to their large contributions to total stresses. And then, different joint types are considered and the leg-hull interface stiffness is analyzed for the improvement of the joint dynamic stress amplitude. Finally, some useful conclusions are drawn for the optimization design of the self-elevating platform.

Plasma apo CⅢ Levels in Relation to Inflammatory Traits and Metabolic Syndrome in Patients not Treated with Lipid-lowering Drugs Undergoing Coronary Angiography

Objective Assessment of the comprehensive relationship among apolipoprotein CIII（apoCⅢ） levels, inflammation, and metabolic disorders is rare. Methods A total of 1455 consecutive patients not treated with lipid-lowering drugs and undergoing coronary angiography were enrolled in this cross-sectional study. A mediation analysis was used to detect the underlying role of apoCⅢ in the association of inflammation with metabolic syndrome（MetS）. Results Patients with MetS showed higher levels of apoCⅢ [95.1（73.1-131.4） vs. 81.7（58.6-112.4） μg/mL, P 〈 0.001] and inflammatory markers [high sensitivity C-reactive protein, 1.7（0.8-3.4） vs. 1.1（0.5-2.2） mg/L; white blood cell count,（6.48 ± 1.68） vs.（6.11 ± 1.67） × 10~9/L]. The levels of apoCⅢ and inflammatory markers increased with the number of metabolic risk components（all P 〈 0.001）. Furthermore, apoCⅢ levels were associated with virtually all individual MetS risk factors and inflammatory markers（all P 〈 0.05）. Importantly, the prevalence of MetS in each metabolic disorder rose as apoCⅢ levels increased（all P 〈 0.05）. Mediation analysis showed that apoCⅢ partially mediated the effect of inflammation on MetS independently from triglycerides. Conclusion Plasma apoCⅢ levels were significantly associated with the development and severity of MetS, and a role of apoCⅢ in the effect of inflammation on the development of MetS was identified.

Effect of Glucose-lowering of Heteropolytungstogermanate β-K_6H[GeW_9V_3O_(40)]·9H_2O

Preliminary tests in rats have shown that the title complex is an efficient insulin mimic, which may be the first example of polyoxomatalates possessing insulin mimetic activity.

Frequency-locking and threshold current-lowering effects of a quantum cascade laser and an application in gas detection field

In this paper,the frequency-locking and threshold current-lowering effects of a quantum cascade laser are studied and achieved.Combined with cavity-enhanced absorption spectroscopy,the noninvasive detection of H_2 with a prepared concentration of 500 ppm in multiple dissolved gases is performed and evaluated.The high frequency selectivity of 0.0051 cm^-1 at an acquisition time of 1 s allows the sensitive detection of the（1-0） S（l） band of H_2 with a high accuracy of（96.53±0.29）%and shows that the detection limit to an absorption line of 4712.9046 cm^-1 is approximately（17.26±0.63） ppm at an atmospheric pressure and a temperature of 20 ℃.

Analytical model including the fringing-induced barrier lowering effect for a dual-material surrounding-gate MOSFET with a high-κ gate dielectric

By solving Poisson＇s equation in both semiconductor and gate insulator regions in the cylindrical coordinates, an analytical model for a dual-material surrounding-gate （DMSG） metal-oxide semiconductor field-effect transistor （MOSFET） with a high-k gate dielectric has been developed. Using the derived model, the influences of fringing-induced barrier lowering （FIBL） on surface potential, subthreshold current, DIBL, and subthreshold swing are investigated. It is found that for the same equivalent oxide thickness, the gate insulator with high-k dielectric degrades the short-channel performance of the DMSG MOSFET. The accuracy of the analytical model is verified by the good agreement of its results with that obtained from the ISE three-dimensional numerical device simulator.

The influence and explanation of fringing-induced barrier lowering on sub-100 nm MOSFETs with high-k gate dielectrics

The fringing-induced barrier lowering（FIBL） effect of sub-100 nm MOSFETs with high-k gate dielectrics is investigated using a two-dimensional device simulator.An equivalent capacitance theory is proposed to explain the physics mechanism of the FIBL effect.The FIBL effect is enhanced and the short channel performance is degraded with increasing capacitance.Based on equivalent capacitance theory,the influences of channel length,junction depth,gate/lightly doped drain（LDD） overlap length,spacer material and spacer width on FIBL is thoroughly investigated.A stack gate dielectric is presented to suppress the FIBL effect.

Effects of lactic acid bacteria isolated from fermented mustard on lowering cholesterol

Objective:To evaluate the ability of lactic acid bacteria(LAB)strains isolated from fermented mustard to lower the cholesterol in vitro.Methods:The ability of 50 LAB strains isolated from fermented mustard on lowering cholesterol in vitro was determined by modified o-phtshalaldehyde method.The LAB isolates were analyzed for their resistance to acid and bile salt.Strains with lowering cholesterol activity,were determined adherence to Caco-2 cells.Results:Strain B0007,B0006 and B0022 assimilated more cholesterol than BCRC10474 and BCRC17010.The isolated strains showed tolerance to pH 3.0 for 3h despite variations in the degree of viability and bile-tolerant strains,with more than 10~s CFU/mL after incubation for 24 h at 1%oxigall in MRS.In addition,strain B0007 and B0022 identified as Lactobacillus plantarum with 16S rDNA sequences were able to adhere to the Caco-2 cell lines.Conclusions:These strains B0007 and B0022 may be potential functional sources for cholesterollowering activities as well as adhering to Caco-2 cell lines.

Modeling of the drain-induced barrier lowering effect and optimization for a dual-channel 4H silicon carbide metal semiconductor field effect transistor

A new analytical model to describe the drain-induced barrier lowering （DIBL） effect has been obtained by solving the two-dimensional （2D） Poisson＇s equation for the dual-channel 4H-SiC MESFET （DCFET）. Using this analytical model, we calculate the threshold voltage shift and the sub-threshold slope factor of the DCFET, which characterize the DIBL effect. The results show that they are significantly dependent on the drain bias, gate length as well as the thickness and doping concentration of the two channel layers. Based on this analytical model, the structure parameters of the DCFET have been optimized in order to suppress the DIBL effect and improve the performance.

Multi-Scale Organization of the Doumbouo-FokouéBauxites Ore Deposits (West Cameroon): Implication to the Landscape Lowering

Landscape distribution, macroscopic, microscopic, mineral and geochemical characterizations were conducted on the Doumbouo-Fokoué bauxite ore deposit in order to estimate bauxites potential and its implication to general lowering of the relief. Fourteen bauxitic plateaus covering a surface area of 5.7 km2 were identified. Bauxitic pedons show deep weathered profiles (10.0 - 12.0 m) with thick bauxitic mantle (4.0 - 8.0 m). Saprolite and pisolith bauxitic facies own high aluminium (47.5% - 49.5% Al2O3), relatively low iron (20.0% - 22.0% Fe2O3) and low silica contents (1.8% - 7.6% SiO2). Gibbsite is the dominant mineral (49% - 68% of minerals detected by X-ray);meanwhile hematite, goethite and kaolinite occur in small amounts. Bauxitization corresponds to intense allitization with abundant accumulation of gibbsite and development of lateritic iron bearing ortho-bauxites. Bauxite ores yielded bauxite reserves of 9.2 million tons. They occur as old and residual bauxitic mantles representing remnants of the Miocene residual lateritic deposits in West Cameroon referring to the African surface of Valeton [1]. Its mean altitude (1532 - 1590 m als) below the African surface reveals general lowering of the relief.

Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China

The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic matter(OM)enrichment throughout this period is still controversial.Based on geochemical data,the marine redox conditions,paleogeographic and hydrographic environment,primary productivity,volcanism,and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section,Chaohu,to provide new insights into OM accumulation.Five Phases are distinguished based on the TOC and environmental variations.In Phase I,anoxic conditions driven by water restriction enhanced OM preservation.In Phase II,euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM deposition.During Phase III,intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation condition.Phase IV was characterized by a relatively higher abundance of mercury(Hg)and TOC(peak at 16.98 wt%),indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic environment.In Phase V,extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary productivity.Phases I,II and IV are characterized as the most prominent OM-rich zones due to the effective interactions of the controlling factors,namely paleogeographic,hydrographic environment,volcanism,and redox conditions.

Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA

Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.

Effect of Uric-acid-lowering Therapy on Progression of Chronic Kidney Disease: A Meta-analysis

The efficacy and safety of uric-acid-lowering therapy （UALT） on slowing the progression of chronic kidney disease （CKD） accompanied by hyperuricemia were assessed. We searched Cochrane Library, PubMed, EMbase, CNKI, Wanfang and Vip databases up to November 15, 2012 for randomized controlled trials （RCTs） which compared the effect of UALT to control therapy in hyperuricemic patients secondary to CKD, and then performed quality evaluation and meta-analysis on the included studies. Seven RCTs involving 451 cases were included. UALT delayed the increase of serum creatinine （MD=-62.55 μol/L, 95% CI： -98.10 to -26.99） and blood urea nitrogen （MD= -6.15 mmol/L, 95% CI -8.17 to -4.13） as well as the decrease of glomerular filtration rate [MD=5.65 mL/（min.l.73 m2）, 95% CI： 1.88 to 9.41], decreased systolic blood pressure （SBP） （MD= -6.08 mmHg, 95% CI： -11.67 to -0.49）, and reduced the risk of the renal disease progression （RR=0.30, 95% CI： 0.19 to 0.46）. However, there was no statistically significant difference in 24-h urinary protein quantity and diastolic blood pressure （P〉0.05）. We identified that UALT could delay the progression of CKD with secondary hyperuricemia. And this also indirectly proved that hyperuricemia was a risk factor for the CKD progression.

IOP-lowering effects for the application of human umbilical vein in non-penetrating deep sclerostomy in rabbits

AIM: To estimate the effects of human umbilical vein (HUV) implanted under the sclera of glaucoma model on intraocular pressure (IOP) lowering and to investigate its related mechanisms METHODS: A total of 20 human umbilical veins (HUV) were collected from healthy fetus umbilical core. After the establishment of glaucoma model in rabbits, human freeze-dried umbilical vein was implanted under the sclera during NPDS, while for control group, sclerostomy was performed without implant. The formation of the filtration bleb and TOP were detected every 24 hours before surgery and on day 3, 7, 10 and 14 after surgery. Handheld pen-type Tono-pen II tonometer was used to measure TOP after topical anesthesia treatment. Each measurement has three duplicates. The incision recovery, filtration, conjunctiva congestion and anterior chamber inflammation were observed everyday after surgery. RESULTS: IOP was decreased dramatically with less inflammation than traditional sclerostomies with the application of HUV. The significant differences of IOP between the NPDS with and without HUV implant groups were shown up from 10 days after surgery. The average TOP in NPDS without HUV implant was 14.25mmHg, while for NPDS with HUV implant group, it was 12.30mmHg. This structure of filtration bleb, which allowed the aqueous humor to leave the eye, was formed for any type of surgery. However, 1-2 weeks later, filtration bleb was still Existed in the group of sclerostomy with HUV implant and more stable than that of the surgery without HUV implant. Histological observations were performed on day 3, 7 and 14 after surgery. For the eyes under sclerostomy with HUV implant, HUV lumina was shown up on 3 days after surgery with few fibroblast cells near the sclera. On 7 days after surgery, HUV lumina was stably maintained but with obvious fibroblast cells and inflammatory cell. On 14 days after surgery, HUV lumina was still clearly observed but with scarring formation, which suggests that the IOP lowering effects might result from an effective drainage structure formation. CONCLUSION: HUV might be an alternative material to make the drainage pathway for non-penetrating deep sclerostomy.

Study on Response Surface Methodology Optimization for Extraction Process of Cyclocarya paliurus Extract and Its Blood Sugar-lowering Effect

[Objectives]This study was conducted to discuss the mechanism of the blood sugar-lowering effect of Cyclocarya paliurus extract.[Methods]With C.paliurus leaves as the raw material,the ethyl acetate-butyl acetate microwave extraction process of C.paliurus was studied.With the yield of C.paliurus extract as an evaluation index,single-factor experiments were carried out on such 6 factors as the dry C.paliurus leaf powder size,solid-to-liquid ratio,extraction time,microwave frequency,microwave power,and microwave extraction time,and the extraction and purification process was further optimized by response surface analysis.The normal mice and the hyperglycemic mice modeled by alloxan were injected with C.paliurus extract to study the blood sugar-lowering effects of different groups of C.paliurus extract.[Results]The optimal process combination for the extraction of C.paliurus leaves was obtained:dry C.paliurus powder size 90-100 mesh,solid-to-liquid ratio 1∶20(g/ml),extraction time 192 min,microwave frequency 2500 MHz,microwave power 490 W,and extraction time 248 s.Under these conditions,the yield of C.paliurus extract reached the maximum,95.10%,reaching 99.83%of the predicted value.The blood sugar-lowering test on mice showed that the C.paliurus extract had a good effect on lowering blood sugar,indicating that C.paliurus extract can improve the free radical scavenging capacity to a certain extent.[Conclusions]This study provides certain reference for the in-depth study of the physiological effects of C.paliurus extract and the comprehensive development and utilization of C.paliurus extract.