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Background The importance of the lipid-related biomarkers has been implicated in the pathological process and prognosis of acute myocardial infarction (AMI). Our work was conducted to discuss and compare the predictive ability of the neutrophil to high-density lipoprotein cholesterol (HDL-C) ratio (NHR) with other existing prognostic indices, for instance, the monocyte to HDL-C ratio (MHR) and the low-density lipoprotein cholesterol (LDL-C) to HDL-C ratio (LDL-C/HDL-C) in elderly patients with AMI. Methods Our population was 528 consecutive elderly AMI patients (65–85 years) who were enrolled from Tongji Hospital and grouped according to the cutoff points which were depicted by the receiver operating characteristic (ROC). The Kaplan-Meier curves were plotted with the survival data from the follow-up to investigate the difference between cutoff point-determined groups. Moreover, we assessed the impact of NHR, MHR, LDL-C/HDL-C on the long-term mortality and recurrent myocardial infarction (RMI) with Cox proportional hazard models. Results Mean duration of follow-up was 673.85 ± 14.32 days (median 679.50 days). According to ROC curve analysis, NHR ≥ 5.74, MHR ≥ 0.67, LDL-C/HDL-C ≥ 3.57 were regarded as high-risk groups. Kaplan-Meier analysis resulted that the high-NHR, high-MHR and high-LDL-C/HDL-C groups presented higher mortality and RMI rate than the corresponding low-risk groups in predicting the long-term clinical outcomes (log-rank test: all P  < 0.050). In multivariate analysis, compared with MHR and LDL-C/HDL-C, only NHR was still recognized as a latent predictor for long-term mortality (harzard ratio [HR]: 1.96, 95% confidence interval [CI]: 1.02 to 3.75, P  = 0.044) and long-term RMI (HR: 2.23, 95% CI: 1.04 to 4.79, P  = 0.040). Furthermore, the positive correlation between NHR and Gensini score ( r  = 0.15, P  < 0.001) indicated that NHR was relevant to the severity of coronary artery to some extent. Conclusions NHR, a novel laboratory marker, might be a predictor of the long-term clinical outcomes of elderly patients with AMI, which was superior to MHR and LDL-C/HDL-C.

Objective To systematically evaluate the guidelines for the diagnosis and treatment of radioactive enteritis, compare their differences and reasons and provide some reference for updating them. Methods This study used guidelines related to radiation enteritis by searching a database. Four independent reviewers used the AGREE II evaluation tool to evaluate the quality of the included guidelines, collate their main recommendations, and analyze the highest evidence supporting the main recommendations. Results Six diagnostic and therapeutic guidelines for radiation enteritis were included in this study, one of which, the American Society for Gastrointestinal Endoscopy guidelines, had an overall score of over 60%, which is worthy of clinical recommendation. In the diagnosis and treatment of radioactive rectal injury, the recommendations for hemorrhagic endoscopic treatment are mature and mainly include (I) argon plasma coagulation; (II) formalin treatment; (III) bipolar electrocoagulation; (IV) heater probe; (V) radiofrequency ablation; and (VI) cryoablation. Conclusion The methodological quality of radioactive enteritis guidelines is unequal; even in the same guidelines, different domains have a large difference. For radioactive rectal damage diagnosis, a type of endoscopic treatment recommendation is more mature, but the overall diagnosis and treatment of radioactive enteritis still lacks high-quality research evidence. Key point This article reviews the diagnosis and treatment guidelines for radiation enteritis in order to promote further update of the guidelines.

The low shear rate interfacial slip behaviors of nonentangled bead–spring polymer melts are firstly simulated using a multiscale method without constitutive relations and wall slip hypotheses. Two orders of magnitude less computation compared with pure molecular dynamics simulations offers the present multiscale method unique capability to resolve the low shear rate slip problems for complex fluids, and to explore the impacts of bulk viscosity and interfacial friction coefficient on slip phenomenon detailedly. Variation of wall–fluid interaction (WFI) can lead to completely opposite trends of rate-dependent slip. For weak WFI, two distinct slip regimes including rate-independent regime and rapid increase regime can be found due to the competition between bulk viscosity and interfacial friction coefficient. For moderate WFI, the complete dominance of the bulk viscosity leads to a linear relation between the slip length and the bulk viscosity and two distinct regimes composed of rate-independent regime and rapid decrease regime.

Gastric cancer (GC) is one of the most malignant tumors, accounting for 10% of deaths caused by all cancers. Chemotherapy is often necessary for treatment of GC; the FOLFOX regimen is extensively applied. However, multidrug resistance (MDR) of GC cells prevents wider application of this treatment. Ubenimex, an inhibitor of CD13, is used as an immune adjuvant to treat hematological malignancies. Here, we demonstrate that CD13 expression positively correlates with MDR development in GC cells. Moreover, Ubenimex reverses the MDR of SGC7901/X and MKN45/X cells and enhances their sensitivity to FOLFOX, in part by decreasing CD13 expression, which is accompanied by downregulation of Bcl-xl, Bcl-2, and survivin expression; increased expression of Bax; and activation of the caspase-3-mediated apoptotic cascade. In addition, Ubenimex downregulates expression of membrane transport proteins, such as P-gp and MRP1, by inhibiting phosphorylation in the PI3K/AKT/mTOR pathway to increase intracellular accumulations of 5-fluorouracil and oxaliplatin, a process for which downregulation of CD13 expression is essential. Therefore, the present results reveal a previously uncharacterized function of CD13 in promoting MDR development in GC cells and suggest that Ubenimex is a candidate for reversing the MDR of GC cells.

Output performance prediction of thermoelectric generators (TEG) is a valuable work for TEG structure optimization (i.e. shape of thermocouple and other electrical or thermal conducting components) and material selection. Considering the basic thermoelectric effects, as well as the thermal resistances between the thermocouple and the heat source, heat sink, this paper describe a physical model with Thomson effect for a simplified thermoelectric module. A new method to solve the temperature of the thermocouple hot and cold conjunctions which directly affect the voltage, current and output power, is proposed. And an experiment test of a commercial Bi2Te3 thermoelectric module is undertaken to testify the physical model and the solution method. The study shows that the calculation results are in good accordance with the experiment data, which prove the accuracy of the physical model and the solution method. This paper can provide a novel analytical method for TEG performance prediction.

Mechanism of hypersonic inlet performance promoting by “virtual cowl” induced by laser energy is introduced, and the physical model of interaction between laser energy and shocks in hypersonic flow field is established. Through comparing results in this paper with the work performed by Macheret et al.(Princeton University) and analyzing effects of laser energy deposited in hypersonic flow, numerical program and the feasibility of model are validated. At Mach 6, with no laser energy addition, air mass capture ratio Km is 71.87% in this paper, while Km is 73.17% in the reference. Energy addition module can simulate the formation of shocks induced by laser energy, and the interaction process between laser energy and compression ramp shocks properly. Curves of mass capture ratio Km agrees well with that of the reference. Km is a little higher than data in the reference, but the variable trend is consistent with each other when laser power is 1kW. When laser power is 0.5kW, Km varies a little, and the peak value is 77.36%, which only increases 7.64%, while the value is 7.28% in the reference.

Wave drag is high when vehicle flights in supersonic, which impacts on aerodynamic performance of the vehicle heavily, so how to reduce wave drag becomes an important problem which needs to be solved. As an active-controlling technology on flow, drag reduction by laser energy deposition has been paid more and more attention to by researchers. Based on Euler equations, mechanical model and numerical method of drag reduction induced by laser plasma are established. Effect on drag reduction performance of hemispherical blunt body of laser energy, blunt size, temperature and pressure of surrounding gas is studied. A dimensionless energy factor is extracted according to numerical results. Results indicate: drag reduction percentage increases with dimensionless energy factors increasing when dimensionless energy factor is less than 0.7; when dimensionless energy factor is greater than 0.7, energy will reach saturation, and drag reduction percentage keeps constant approximately; power efficiency decreases with dimensionless energy factors increasing. Therefore, similar law of drag reduction performance by laser plasma is obtained preliminarily, which provides possibility for reliable amplification of drag reduction by laser energy deposition.

To measure the propulsion characters of PVC(poly vinyl chloride) doped with carbon ablated by high power density laser, torsion pendulum is used to measure the micro impulse. Laser interference is used to detect the vibration of the pendulum which is caused by the ablating jet. The measurement error is 2.6 according to the calibration. Nd:YAG laser is used as the laser source. Mettler-Toledo XS105DU analytical balance is used to measure the ablated mass. The results indicate that the performance of PVC+2C is better as an alternate target. Both the specific impulse(Isp) and energy transforming efficiency() increase with laser power density(I0), while momentum coupling coefficient(Cm) decreases. The maximum measured Cm is 557N/W. Isp and  reach to 204s and 46 respectively.

The concept of a UAV (unmanned aerial vehicle) with photovoltaic cells powered by a laser beam has been demonstrated as more firm, having higher usable power and more payloads than solar-powered ones, and features wide prospective. The theory models were based on the thermal equilibrium formulation which took into account of convective cooling raised by the flowing air and the radiation heat exchanges between the photovoltaic panel and the earth, and the atmosphere. Then, numerically, this paper investigated and analyzed the equilibrium temperature, energy efficiency, usable laser power density and maximum endurable laser power density of the photovoltaic panel, which can provide references for the choice of cooling methods and laser-power mission programming of the laser-powered UAVs.

In order to develop a potential way to reduce the stagnation pressure and heat flux of the blunt body in hypersonic flow, single pulsed and high rated laser energy are deposited respectively to control the bow shock in Mach 5 flow. Process of the interaction of 100mJ single pulsed laser energy with bow shock is studied by schlieren experiment in Mach 5 shock tunnel. The results indicate that the schlieren photographs and stagnation pressure at different times fit well with the simulation. Bow shock is distorted by the laser induced blast wave. During a single laser pulse, the average stagnation pressure and temperature are reduced by 6.5% and 3.4%. High rated laser energy is used to sustain the low pressure and heat flux region to increase the control efficiency. With the power of 6.6% of the enthalpy flux, when the distance of deposition point and blunt body is 1.1 times of the diameter of the blunt body, the pressure and heat flux of the stagnation point is reduced to 49% and 75%, respectively. The mechanism of interaction of laser and bow shock is disclosed.