The predictive role of the neutrophil-lymphocyte ratio in the prognosis of adult patients with stroke

Our study aimed to determine the effect of the neutrophil-lymphocyte ratio on the prognosis of adult patients with acute stroke.We searched the Web of Science,PubMed,Embase,Cochrane Library,and China National Knowledge Infrastructure databases and selected all of the potentially eligible studies.From the included studies,we extracted characteristics such as the stroke type and acquisition time until routine blood collection and the odds ratios across studies.The 95%confidence intervals and odds ratios were pooled to calculate the effect size for the neutrophil-lymphocyte ratio in acute stroke patients.We defined poor function outcomes according to the modified Rankin Scale≥3 or Glasgow Outcome Scale<3.Thirteen studies with 4443 patients were included in our analysis,including 7 ischemic and 6 hemorrhagic stroke studies.The pooled odds ratios for poor functional outcome at 3 months with a higher neutrophil-lymphocyte ratio in acute ischemic and hemorrhagic patients were 1.689(95%CI=1.184-2.409,p<0.001)and 1.125(95%CI=1.022-1.239,p<0.001),respectively,and the overall pooled odds ratio for poor functional outcome following stroke was 1.257(95%CI=1.146-1.379,p<0.001).At the same time,the overall combined odds ratio for death at 3 months was 1.632(95%CI=1.155-2.306,p<0.001).The neutrophil-lymphocyte ratio,an easily calculated marker,plays a predictive role in the short-term outcomes of adult patients(mean age≥50 years)following acute ischemic and hemorrhagic stroke.

Research on carbon emissions embodied in China-Russia trade under the background of the Belt and Road

Based on the latest China-Russia input-output data sets over the period from 2007 to 2015,this study quantified the flow of embodied carbon emissions in China-Russia trade using the emission embodied in bilateral trade(EEBT)approach.In addition,the structural decomposition analysis(SDA)was employed to identify the potential driving factors that affect embodied carbon in imports and exports.The results showed as follow.1)China was a net exporter of carbon emissions in bilateral trade between China and Russia during 2007–2015.Despite that the bilateral trade scale had expanded considerably,the net export volume of CO_(2)from China to Russia decreased from 13.21 Mt in 2007 to 4.45 Mt in 2015.2)From the perspective of different sectors,the metal manufacturing and the chemical sectors of China and Russia were the main sources of CO_(2)emissions.3)In terms of driving factors,it was found that the carbon emission coefficient was the main reason for contributing to embodied emission reduction.Moreover,the contribution rate of carbon emission coefficient to reduce the carbon emissions in imports reached to 95.26%,as well as 108.22%in exports.The bilateral trade scale was the main driver for the increase in embodied carbon emissions,and the contribution rate to embodied carbon emissions in imports and exports were 14.80%and 65.17%,respectively.4)This study argued that China and Russia should further optimize the energy structure and improve the energy efficiency and intermediate technology in the future.

The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China

Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in Shenyang.

Boundary-layer transition of advanced fighter wings at high-speed cruise conditions

The achievement of laminar flow in the boundary layer at high-speed cruise conditions may further, in addition to shock-wave control, reduce the drag and extend the range of military fighter aircraft. To this end, a further investigation on transitional boundary-layer flow of fighter wings is needed due to different configurations from the wings used on conventional transport aircraft. In this paper, wind tunnel experiments and numerical simulations were conducted on three-dimensional transition of thin diamond-shaped wings used on advanced fighter aircraft at tran/supersonic design points. A newly proposed correlation of crossflow transition which includes the effect of surface roughness was introduced into the c-Rehttransition model. Predicted results were in good agreement with flow visualizations. Results showed that the strength of the crossflow component grew rapidly around the leading edge because of the severe flow acceleration, just as the same as wings with a large aspect ratio. However, there seemed no regular pattern of instabilitydominance variation in span-wise for a diamond configuration. The dominance of different instability mechanisms strongly depended on the local pressure distribution. Hereby, the research recommended a ‘‘roof-like" shape of pressure distribution to suppress both crossflow and Tollmien-Schlichting(T-S) instabilities. Besides, a sharp suction peak with a serious pressure rise should be cut off to avoid stronger instabilities. Further discussions also revealed an independence of the unit Reynolds number when transition was triggered by T-S instabilities. Aerodynamic force comparisons indicated that further benefit on drag reduction could be expected by including the three-dimensional transition effect into a wing design process.

Unstable unsteady aerodynamic modeling based on least squares support vector machines with general excitation

Common,unsteady aerodynamic modeling methods usually use wind tunnel test data from forced vibration tests to predict stable hysteresis loop.However,these methods ignore the initial unstable process of entering the hysteresis loop that exists in the actual maneuvering process of the aircraft.Here,an excitation input suitable for nonlinear system identification is introduced to model unsteady aerodynamic forces with any motion in the amplitude and frequency ranges based on the Least Squares Support Vector Machines(LS-SVMs).In the selection of the input form,avoiding the use of reduced frequency as a parameter makes the model more universal.After model training is completed,the method is applied to predict the lift coefficient,drag coefficient and pitching moment coefficient of the RAE2822 airfoil,in sine and sweep motions under the conditions of plunging and pitching at Mach number 0.8.The predicted results of the initial unstable process and the final stable process are in close agreement with the Computational Fluid Dynamics(CFD)data,demonstrating the feasibility of the model for nonlinear unsteady aerodynamics modeling and the effectiveness of the input design approach.