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Chassis dynamometer experiments were conducted to investigate the effect of vehicle speed and usage of ethanol-blended gasoline (E10) on formation and evolution of gasoline vehicular secondary organic aerosol (SOA) using a Gothenburg Potential Aerosol Mass (Go: PAM) reactor. The SOA forms rapidly, and its concentration exceeds that of primary organic aerosol (POA) at an equivalent photochemical age (EPA) of ~1 day. The particle effective densities grow from 0.62 ± 0.02 g cm−3 to 1.43 ± 0.07 g cm−3 with increased hydroxyl radical (OH) exposure. The maximum SOA production under idling conditions (4259–7394 mg kg-fuel−1) is ~20 times greater than under cruising conditions. There was no statistical difference between SOA formation from pure gasoline and its formation from E10. The slopes in Van Krevelen diagram indicate that the formation pathways of bulk SOA includes the addition of both alcohol/peroxide functional groups and carboxylic acid formation from fragmentation. A closure estimation of SOA based on bottom-up and top-down methods shows that only 16%–38% of the measured SOA can be explained by the oxidation of measured volatile organic compounds (VOCs), suggesting the existence of missing precursors, e.g. unmeasured VOCs and probably semivolatile or intermediate volatile organic compounds (S/IVOCs). Our results suggest that applying parameters obtained from unified driving cycles to model SOA concentrations may lead to large discrepancies between modeled and ambient vehicular SOA. No reduction in vehicular `SOA production is realized by replacing normal gasoline with E10.

Traffic-related volatile organic compounds (VOCs) emissions are regarded as the primary anthropogenic source of ambient VOCs in urban areas and precursors to ozone formation. Given the extensive use of gasoline-ethanol mixtures on light-duty vehicles, it is essential to discuss its effects on the atmospheric environment, especially the VOCs emissions and ozone forming potential (OFP) values of one typical formulation called the “match-blend.” In this paper, VOCs emission factors, VOCs distributions, specific reactivity (SR) values, and OFP values of a China-6 commercial gasoline and four E10 match-blend fuels used on seven China-6 vehicles were studied. Thirteen carbonyls detected by high-performance liquid chromatography along with seven VOCs detected by gas chromatography-mass spectrometry were considered in the calculation of OFP and SR. Besides, the effects of test temperatures are discussed. Results show that ethanol increases VOCs emissions, OFP, and SR values at cold-start/room temperature, but behaves oppositely at cold-start/low temperature. Increases in heavy aromatics always lead to higher VOCs emissions and OFP values.

For a multi-component hydrocarbon mixture under supercritical conditions, especially for fuels injected into compression ignition engines, the mechanism for the transition of the dominant mixing mode from evaporation to diffusion is not well established. In this paper, evaporation processes of a six-component hydrocarbon fuel (13.16 mol% toluene, 13.81 mol% n-decane, 22.30 mol% n-dodecane, 24.60 mol% n-tetradecane, 14.66 mol% n-hexadecane and 11.47 mol% n-octadecane) droplet in nitrogen environments were studied using molecular dynamics (MD) simulations, in comparison with those of three-component and single-component fuel droplets. The ambient pressure ranged from 2 MPa to 16 MPa and the ambient temperature ranged from 750 K to 1350 K. Results indicated that the transition characteristics of the mixed fuel were not the linearly weighted average of the physical properties of individual components in the mixture based on their mole fractions. The reason why there is a limitation on the maximum transition temperature when diffusion dominates the fuel-ambient gas mixing process under high pressures has been discussed. The average resultant force on a fuel atom of an individual component increases with increasing pressure or decreasing temperature at the supercritical temperature, and diffusion will gradually dominate the mixing process of the fuel. The clustering behavior of fuels under supercritical conditions has also been discussed.

In this article, Brownian coagulation of particles in the exhaust system of a gasoline engine were investigated by measuring particle size distribution (PSD) at different sampling points and Monte Carlo simulation. The measurement results show that the particle size distributions of nucleation mode (NM) change remarkably after the exhaust gas passes through the exhaust plenum chamber. The constructed coagulation model based on the classic coagulation theory can well catch the measured PSDs, particle number (PN) concentrations, and count median diameters (CMDs) along the exhaust system under both the in-cylinder direct injection and port fuel injection modes, indicating that the particle process in the exhaust system is dominated by coagulation. The NM PN concentration decreases, and the NM CMD increases in the downstream exhaust gas, and the changes are more significant at higher accumulation mode (AM) PN concentration conditions. The coagulation history provided by modelling shows that coagulation mainly occurs between two NM particles (NM-NM) or one NM and one AM particles (NM-AM). At higher AM PN concentration conditions, the NM-AM coagulation dominates and quickly eliminates NM particles, resulting in more significant NM particle reduction. The PN concentration variation as a function of time indicates that PN concentration decreases quickly at first and then the decreasing rate slows down.

In 2017, the Chinese government issued a strategic policy of nationwide use of bioethanol as a gasoline-blending component by 2020 for the consideration of reducing smog and greenhouse gas (GHG) emissions. It is highly relevant to estimate the benefits of well-to-wheel (WTW) GHG emission savings using future engine technologies. However, literature about the WTW GHG emissions for ethanol blends did not cover the engine efficiency gains in engines with future technologies. In a previous publication from the authors’ group, an empirical model was developed to predict the anti-knock property and engine thermal efficiency gains of ethanol blends in spark-ignition (SI) engines. This paper is a follow-up study, looking at not only the potential engine thermal efficiency gains but also WTW GHG emissions in future engine technologies. More specifically, a case study of adding bioethanol to two representative E10 fuels (main- and premium-octane-grade fuels) from China was conducted. It is assumed that future engin...

Background Branchial anomalies (BAs) account for 20% of all congenital masses in children. We sought to review the incidence of involvement of individual anomalies, diagnostic methods, surgical treatment, and complications of BAs in children. In addition, we also classified our study and analyzed a congenital lower neck cutaneous fistula near the sternoclavicular joint that was thought to be the skin-side remnant of the fourth BAs. Methods We conducted a retrospective analysis of 105 children who were referred to our hospital from June 2009 to December 2016 for the treatment of BAs. Results In this series, there were 51 males and 54 females. The age at the time of operation varied from 19 days to 13 years, and the mean age was 4.5 years. A total of 33 (31.4%) cases presented with first BAs, 13 (12.4%) presented with second BAs, and 59 (56.2%) presented with third and fourth BAs, including 6 cases of congenital lower neck cutaneous fistula. Fistulectomy under general anesthesia was performed on all of them. For postoperative complications, 2 cases had temporary facial paralysis, 1 case had permanent facial paralysis, 4 cases had temporary recurrent laryngeal nerve injury. Recurrence occurred in 2 patients with first BAs after medium follow-up time of 3.6 years (6 months–8 years). Conclusions BAs are common congenital head and neck lesions in children, and there are four distinct types (first, second, third and fourth anomalies). The incidence of third and fourth BAs in Asia maybe higher when compared with literature reports, second BAs seem rare in this population, but more research is needed to confirm this perspective. Diagnosis is not difficult with a proper knowledge of the anatomy of the BAs. The surgical procedures should be tailored depending on the various types, and complete excision of the fistula is the key to prevent recurrence.

Microscopic and macroscopic impingement characteristics of a single jet were investigated under various flash boiling conditions. The influences of split injection strategy and the related interaction between split injections were studied. The fuel concentration distribution during the impingement process was also quantified. It was found that non-flash boiling condition lead to large secondary droplets and ligaments, resulting in a large amount of liquid fuel deposited on the impact surface. The boosted flash boiling could effectively reduce the sizes of primary droplets and secondary droplets and the resultant deposited fuel. The employment of split injection strategy could further decrease the deposited fuel. The second split injection built up the fuel film more quickly than the first injection due to the existence of the built fuel film by the first injection, however, increasing flash boiling strength decreased the building-up rate by improving dispersion and evaporation. In addition, the concentration of the deposited fuel on the surface could effectively be reduced by enhanced flash boiling and the lifetime of dense fuel was shortened by increasing dwell interval between split injections.

The main objective of this study is to investigate the effect of ambient pressure ( P amb ) on the morphology of multi-jet flash boiling sprays and to promote the understanding on the collapse mechanism. With the high-speed imaging technique, the n-hexane spray process in a constant volume vessel was captured under the ambient pressures from 2 kPa to 101.3 kPa and the fuel temperatures ( T fuel ) from 20 °C to 120 °C. The spray width within the axial distances of 20 nozzle diameters ( do ) could be increased by increasing T fuel and/or decreasing P amb . Beyond 20 do , the change in spray width against superheated degree ( ΔT SD ) was fairly sensitive to P amb . It decreased with the increase in ΔT SD at P amb larger than 50 kPa, and increased with ΔT SD at P amb less than 50 kPa. Based on the new understanding that the collapse in multi-jet flash-boiling sprays was induced by vapor condensation at the nozzle exit and the resultant local pressure drop (i.e. generation of low-pressure zone), the sensitivity of spray width on P amb could be well explained as follows: relatively larger P amb (>50 kPa for the used injector) would be conducive to the vapor coagulation and cause stronger vapor condensation (i.e. larger pressure drop) while the vapor dispersion may become dominant at lower P amb (

While deep learning models have demonstrated outstanding performance in medical image segmentation tasks, histological annotations for training deep learning models are usually challenging to obtain, due to the effort and experience required to carefully delineate tissue structures. In this study, we propose an unsupervised method, termed as tissue cluster level graph cut (TisCut), for segmenting histological images into meaningful compartments (e.g., tumor or non-tumor regions), which aims at assisting histological annotations for downstream supervised models. The TisCut consists of three modules. First, histological tissue objects are clustered based on their spatial proximity and morphological features. The Voronoi diagram is then constructed based on tissue object clustering. In the last module, morphological features computed from the Voronoi diagram are integrated into a region adjacency graph. Image partition is then performed to divide the image into meaningful compartments by using the graph cut algorithm. The TisCut has been evaluated on three histological image sets for necrosis and melanoma detections. Experiments show that the TisCut could provide a comparative performance with U-Net models, which achieves about 70% and 85% Jaccard index coefficients in partitioning brain and skin histological images, respectively. In addition, it shows the potential to be used for generating histological annotations when training masks are difficult to collect for supervised segmentation models.

Gasoline direct injection (GDI) vehicles are up against the great challenge of particulate emissions, which were mandatorily constrained by the China-6 emission standard. Given the worldwide fuel transition from gasoline to gasoline/ethanol blends, it is important to discuss the effects of ethanol and aromatic contents on particulate emissions of GDI vehicles. In this work, 10% volume of ethanol was added into China-6b gasoline replacing C8 (carbon atoms = 8) alkanes (E10), and the specific aromatic compounds in E10 fuels were adjusted under holding total aromatic content. As there was no limit on individual aromatic compounds in the gasoline standard, the effects of aromatic compounds were investigated over the worldwide harmonized light-duty test cycle (WLTC) with engine cold-start and hot-start at room and low temperatures. For GDI vehicles, the results showed that ethanol substituting part of C8 alkanes in gasoline increased the particulate number (PN) but decreased particulate mass (PM) emissions. For vehicles using the combined port fuel injection (PFI)/GDI injection systems, the PM and PN emissions climbed. Aromatic compositions significantly impacted the particulate emissions. With the concentrations of heavy aromatics increased, PM and PN emissions of both GDI and combined-injection vehicles were shown to multiply.

2-Methylfuran (MF) is considered as a promising second-generation biofuel for spark ignition engines. MF has better anti-knock ability, and the lower heating value of MF is close to that of conventional fuels. The production methods of MF have been largely improved over the last decade. However, the studies of MF on direct injection spark ignition (DISI) engines are quite limited, and little is known about the effects of engine control parameters on MF combustion at typical DISI engine operating conditions. In the present work, the effects of engine control parameters including spark timing, air–fuel ratio, injection timing, and injection pressure on combustion and engine performances of MF were studied at typical medium load and high load conditions on a single-cylinder spray-guided DISI engine, compared to gasoline and ethanol. The results show that the achievable spark timing range considering combustion phasing and knock limit for MF is larger than that of gasoline especially at high load. MF has more robustness to lean burn than gasoline and ethanol. The combustion characteristics and heat release of MF have low sensibility to the variation of injection timings. To achieve the same engine load MF requires up to 25% longer injection durations than gasoline, however, increased injection pressure can mitigate the injection duration differences between MF and gasoline.

Biomass energy is an emerging alternative energy source with an attractive carbon balance in its life cycle. Recently, a biomass fast pyrolysis fuel was produced from rice husk, and it was further upgraded using supercritical ethanol with a 5%Pt/SO 4 2− /ZrO 2 /SBA-15 catalyst in a hydrogen atmosphere. This upgraded biomass pyrolysis fuel is mainly composed of ethers, esters, alcohols and ketones. After analysing the composition of this upgraded biomass pyrolysis fuel, the authors reproduced a mixed fuel to mimic the upgraded biomass pyrolysis fuel. This mixed fuel contained ethanol, ethyl acetate, diethyl ether, acetone, and 2-butanone, with mass ratios of 9:6:2:1:1. This fuel has been used in a gasoline engine with some minor modifications; however, there is no data available for its laminar burning characteristics. In this study, the laminar burning characteristics of this mixed fuel were investigated in a constant volume combustion chamber (CVCC) at an initial pressure of 0.1 MPa and initial temperatures of 358, 388 and 418 K), and at an initial temperature of 358 K and initial pressures of 0.1, 0.2 and 0.4 MPa. By using a Schlieren high-speed imaging technique and a linear extrapolation method, laminar burning characteristics including the unstretched flame propagation speed, laminar burning velocity and other key parameters were calculated and discussed. Experiments were also conducted for two main components, ethanol and ethyl acetate, and results were used as benchmarks. The results indicated that the peak laminar burning velocity of the mixed fuel can be observed near the equivalence ratio of 1.1 under the tested conditions. At the same equivalence ratio, the laminar burning velocity was increased as initial temperature was increased, and it was decreased as initial pressure was increased. Markstein length decreased as equivalence ratio was increased, and it dropped below zero when the equivalence ratio was 1.4, indicating increased flame instability with equivalence ratio increased. Among the three examined fuels, the laminar burning velocity ranking was: ethanol > mixed fuel > ethyl acetate.

The anti-knock quality of gasoline fuels is a significant contributing factor to the indicated thermal efficiency (ITE) of spark ignition (SI) engines. Historically, the anti-knock quality of gasoline is characterised by two parameters, research octane number (RON) and motor octane number (MON), which are measured in cooperative fuel research engines (CFR) using iso-octane and n-heptane as the primary reference fuels (PRFs). However, due to significant hardware, operating condition and fuelling differences between the CFR and the modern SI engines, the relevance of RON and MON to modern SI engines needs to be re-assessed. In this study, six fuels were designed with independent control over RON and MON. The other key fuel properties, such as the heat of vaporisation, the oxygen content, the lower heating value and the stoichiometric air-fuel ratio (AFR) were kept similar for all the fuels. Among the six fuels, two fuels represent regular- and premium-grade gasoline fuels with respect to octane quality in the North American market. The objective of this study was to assess the significance of RON and MON to the combustion characteristics of a modern SI engine. A single cylinder 4-stroke direct injection spark ignition (DISI) research engine was used as the experimental tool. The engine tests were conducted at the engine speed of 1800 rpm and the engine load ranging from 4 to 20 bar IMEP. Three market representative engine compression ratios (9.5:1, 10.5:1 and 11.5:1) were selected. In addition, the engine K value was calculated at knock-limited engine conditions. The results showed that, under knock-free engine operating conditions and at a fixed engine compression ratio, variation of fuel RON and MON had almost no differential impact on ITE. Under knock-limited operating conditions, increasing MON did not increase ITE, and in contrast, even led to decreased ITE especially when RON was as low as 93 and the compression ratio was high. Under knock-limited operating conditions, when the RON of the fuel was as high as 98, changing the MON up or down only showed combustion phasing benefits/disbenefits without obvious ITE benefit. This is because the octane rating of the fuel was high and in order to differentiate their anti-knock quality, a higher compression ratio than 11.5:1 was needed. The calculated engine K value shows that RON was a more significant influential factor than MON in determining the engine thermal efficiency. RON was found to have a higher impact on ITE at the higher MON of 88 vs. the lower MON of 83.

Numerous skills involving the introduction of (OP) opposed piston engine have been developed in the recent past. Indeed, novel techniques can help to improve the performance of the engine. The aim of this paper is to model and simulate a simple single-cylinder two-stroke opposed-piston engine and minimise fuel consumption and heat loss, using the software programme AVL BOOST™. AVL BOOST is an engine modelling software, which analyses the performance of a modelled single cylinder two-stroke opposed-piston engine by changing desired parameters. In order to meet this aim, experimental results from a unique engine are used to make a comparison with the results obtained from AVL BOOST model. Six combinations of compression ratios (12, 13.5, 15, 16.5, 18 and 19.5) are analysed in this study with the engine speed running at 420 rpm and 1500 rpm. In addition to the compression ratios, the effect of stroke-to-bore (S/B) ratios on OP2S performance is investigated. Various values of S/B ratios, whilst maintaining a constant swept volume, port geometry and combustion timing, and their effect on fuel consumption and heat loss are analysed in this study. A comparison between the two engine speeds with increasing combinations of compression ratios, and the S/B ratios revealed minimal differences in peak pressure, peak temperature, IMEP, ISFC, indicated efficiency and total heat loss. Detailed analyses of these parameters are highlighted in discrete sections of this paper.

The air path of a turbocharged diesel engine is a multi-input multi-output (MIMO) system with strong nonlinearity, coupling effect, delay and actuator constraints. This makes the design and tuning of the controller complex. In this paper, a tuneable model predictive control (TMPC) controller for a diesel engine’s air path with dual loop exhaust gas recirculation (DLEGR) is presented. The objective is to regulate the intake manifold pressure and exhaust gas recirculation (EGR) mass flow in each loop to meet the time-varying setpoints through coordinated control of the variable geometry turbocharger (VGT) and EGR valves. The TMPC controller adopts the design framework of an MPC controller. This controller is also able to provide a map-based switching scheme for the local controller and the controller’s weightings. A comparison between the TMPC controller and a conventional PID controller is conducted on a validated real-time engine model. The simulation results show that the TMPC controller achieves lower overshoot, faster response and a shorter settling time on the manipulated objects. These improvements are beneficial for obtaining lower fuel consumption. In order to test the capability of the TMPC controller, it is validated on a hardware in the loop (HIL) platform. The results show that the agreement between the simulation and the actual ECU’s response is good.

Injector deposit is a common phenomenon for gasoline direct ignition (GDI) engines that greatly affects the spray behavior and consequently the combustion performance and emissions. In this study, the effect of deposit on both the in-nozzle flow dynamics and downstream spray behaviors was numerically investigated. High-resolution X-ray microtomographic scans were performed first to obtain nozzle and deposit morphologies and topology. In-nozzle simulation was then carried out in the Euler-Euler framework with cavitation taken into account by a homogeneous relaxation model (HRM). Finally, the effect of deposit on spray behaviors was evaluated in the Euler-Lagrangian framework, coupled with the in-nozzle simulation results. Results of the nozzle flow simulations highlight that the rough surface of the deposits leads to additional cavitation inception and restricts the flow area, causing mass flow rate losses. Deposits inside the counterbore act as an extension to the inner orifice and constrain the air recirculation. Turbulent levels at the exit of the counterbore are lower for the coked injector due to the reduced air/fuel interaction. Spray simulations have shown that deposits would lead to longer spray penetration, a smaller spray cone angle and larger droplets diameters. Simulation results agree reasonably well with the available experimental data.

For modern gasoline direct injection (GDI) engines, injector deposit is a concern because it can cause changes to the spray characteristics and lead to deterioration in fuel economy and exhaust emissions. In this study, in order to examine the link between spray variation and engine emissions deterioration due to injector deposit accumulation, 8 new injectors were installed on a GDI engine and run through a deposit accumulation process which included 6 cold starts and a 30-h steady state engine test at a speed of 2000 rpm and load of 5 bar break mean effective pressure (BMEP). One representative injector was examined before and after the deposit accumulation tests in order to understand the impact of deposit on the spray. Results showed that, at the end of the deposit accumulation test, the pulse width of the injectors stabilized at a level which was about 1.5% higher than at the start and the fuel consumption remained almost identical. High magnification and borescope imaging indicated that a significant amount of deposit had formed on the outer surface of the injector tip. However, Scan Electronic Microscope (SEM) imaging of the injector hole showed that, at this level of fouling, some deposit was present on the counterbore, while the nozzle hole was nearly completely unaffected. The deposit on the counterbore caused a 2.21% drop of the injector fuel flow rate at 150 bar injection pressure. Penetration lengths and mean droplet sizes of all jets increased significantly. As for the impacts of the varied spray characteristics on the engine emissions, unburnt hydrocarbons (HC) and particulate matter (PM) emissions significantly increased while other gaseous emissions (e.g. CO, NOx, CO2) only changed slightly.

In order to increase the economic efficiency of conformance control in the time of low oil price, a gelant should be injected into the specified location (positioning conformance control) to improve the swept volume in the maximum extent in the heterogeneous oil reservoir. For this purpose, an in-situ cross-linking polymer gelant (it is consisting of modified starch, acrylamide, N, N'- methylene diacrylamide, and potassium persulfate) is taken as the object of study by CT scan. Based on the dynamic and visible images of fluids distribution in the porous media, the gelant can be used to achieve the positioning conformance control because it can almost maintain a whole slug during transportation in porous media. According to the relationship of transportation distance and injection volume of the gelant in porous media, the gelant can be displaced to the specified location in porous media. In addition, the characteristics of water flooding of heterogeneous porous media before and after positioning conformance control are studied by CT scan, which can investigate the function of positioning conformance control and the extent of improving the swept volume in the heterogeneous reservoirs. The experimental results in this paper can provide theoretical guidance for the practical application of positioning conformance control in the heterogeneous oil reservoirs.

Spray impingement adversely affects fuel mixture preparation, combustion performance and emissions and more studies are required to understand this process. The isooctane spray impingement process and characteristics were investigated by ultrahigh speed imaging technique with the employment of highly spatially resolved long distance microscope. The effects of impact surface temperature were also studied. It was found that during the initial stage and steady stage of spray impingement, a large proportion of droplets splashed due to high velocity. The droplet size after impingement generally reduced because of the strong collision. For the end stage of impingement, droplets tended to stick on the impact surface and float on the fuel film due to the low droplet velocity and the existence of built liquid fuel film. It was also found that hot impact surface could only improve the impingement and reduced the film building-up rate in the initial stage. The steady stage and end stage of spray impingement were less affected by the variation in impact surface temperature.

The application of dieseline fuel (blends of diesel and gasoline) into compression ignition engines has been intensively investigated in recent years due to its good combustion performance and low smoke emissions. In this study, the main objective was to investigate the spray characteristics of dieseline fuel. Macroscopic spray characteristics in terms of spray morphology and penetration were investigated in a constant volume vessel under elevated ambient pressures using high-speed imaging system, while the microscopic spray characteristics including droplet size and velocity distribution were measured at atmospheric condition using Phase Doppler Particle Analyzer (PDPA) system. The results have shown that the gasoline/diesel blending ratio played an important role in affecting the spray atomization process. With the increase of the gasoline/diesel blending ratio, spray penetration length, droplet mean velocity, and droplet Sauter Mean Diameter (SMD) decreased gradually, especially at low injection pressure and low ambient pressure conditions. Both the results of macroscopic and microscopic studies indicate a better atomization quality can be achieved by increasing the proportion of gasoline in the dieseline.

Cyclopentanone, a product of biomass pyrolysis of agricultural waste, has certain advantages as a biofuel candidate but so far little is known about its combustion characteristics. In this paper, the laminar flame characteristics of cyclopentanone, including stretched flame propagation speed, unstretched flame propagation speed, and laminar burning velocity, were measured and compared with gasoline and ethanol, using the outwardly propagating spherical flame method and the high-speed Schlieren photography technique. The experiments were conducted in a constant-volume vessel using various fuel-air equivalence ratios (ϕ = 0.8–1.6) at elevated initial temperatures (T 0 = 423, 448 and 473 K) and a fixed initial pressure (P 0 = 0.1 MPa). Linear and non-linear extrapolations were used to characterise the relationship between the stretch rate and the stretched flame propagation speed when Markstein length was near to or away from zero respectively. Empirical functions were obtained to calculate the laminar burning velocities of cyclopentanone for various fuel-air equivalence ratios and initial temperatures. The results show that Markstein length of cyclopentanone decreases when equivalence ratio is increased, and the turning point of equivalence ratio at which it changes from positive to negative is slightly below 1.4. The maximum laminar burning velocity of cyclopentanone appears at the equivalence ratio of approximately 1.2, regardless of the initial temperature. The laminar burning velocity of cyclopentanone has a smaller difference to that of ethanol and gasoline when equivalence ratio is leaner than stoichiometric, but when equivalence ratio increases from 1.0 to 1.4, it becomes increasingly lower than that of ethanol and higher than that of gasoline. The maximum laminar burning velocity of cyclopentanone is 0.82 m/s; for gasoline it is 0.72 m/s and for ethanol it is 0.86 m/s, at an initial temperature of 423 K and pressure of 0.1 MPa.

Measurement of melanoma depth of invasion (DoI) in skin tissues is of great significance in grading the severity of skin disease and planning patient's treatment. However, accurate and automatic measurement of melanocytic tumor depth is a challenging problem mainly due to the difficulty of skin granular identification and melanoma detection. In this paper, we propose a technique for measuring melanoma DoI in microscopic images digitized from MART1 (i.e., meleanoma-associated antigen recognized by T cells) stained skin histopathological sections. The technique consists of four modules. First, skin melanoma areas are detected by combining color features with the Mahalanobis distance measure. Next, skin epidermis is segmented by a multi-thresholding method. The skin granular layer is then identified based on Bayesian classification of segmented skin epidermis pixels. Finally, the melanoma DoI is computed using a multi-resolution approach with Hausdorff distance measurement. Experimental results show that the proposed technique provides a superior performance in measuring the melanoma DoI than two closely related techniques.

First branchial cleft anomalies (FBCA) are rare in the clinical setting, as they account for 1 to 8% of all branchial abnormalities. The purpose of this study is to explore the relationship between the fistula tract and facial nerve and the surgical method of FBCA. This retrospective study included 30 cases of FBCA in children managed from 2009 to 2016. All patients underwent surgery to remove the tract of the FBCA. We reviewed the clinical data of the patients to obtain their demographics and management. Thirty patients (11 male and 19 female) with anomalies of FBCA were diagnosed. The ages ranged from 1 to 13 years (median, 3 years). Twenty cases had a close relationship with the parotid gland. The facial nerve was identified in 20 of the 30 patients. The tract ran deep to the facial nerve in 3 cases, superficial to it in 21 cases, and passed between the branches of the nerve in 6 cases. The facial nerve was not identified in ten patients, as the tract was superficial to it. There were 2 cases of postoperative temporary facial paralysis (2/30, 6.7%). The symptoms gradually improved after one month, 1 case had permanent facial paralysis (1/30, 3.3%), and 1 case had postoperative recurrence. Complete excision of the tract is the only way to manage FBCA, and the course of the tracts vary and have different relationships with the facial nerve. There are 3 types: Superficial, deep to the facial nerve, and between the branches of the nerve. Therefore, surgical approaches differ among the various types, and careful preoperative planning and protecting the facial nerve during resection of the tract are essential.

Downsized spark ignition engines have the benefit of high thermal efficiency; however, severe engine knock is a challenge. Ethanol, a renewable gasoline alternative, has a much higher octane rating and heat of vaporization than conventional gasoline, therefore, ethanol fuels are one of the options to prevent knock in downsized engines. However, the performance of ethanol blends in modern downsized engines, and the contributions of the research octane number (RON), octane sensitivity (defined as RON-MON) and charge cooling to suppressing engine knock are not fully understood. In this study, eight fuels were designed and tested, including four splash blended ethanol fuels (10 vol.%, 20 vol.%, 30 vol.% and 85 vol.% ethanol, referred to as E10, E20, E30 and E85), one match blended fuel (E0-MB) with no ethanol content but the same octane rating as E30, and three fuels (F1-F3) with different combinations of RON and octane sensitivity. The experiments were conducted in a single-cylinder direct-injection spark ignition (DISI) research engine. Load and spark timing sweep tests at 1800 rpm were carried out for E10-E85 to assess the combustion performance of these ethanol blends. In order to investigate the impact of charge cooling on combustion characteristics, the results of the load sweep for E0-MB were compared to those of E30. Load sweep tests were also carried out for F1-F3 to understand the impacts of RON and octane sensitivity on suppressing engine knock. The results showed that at the knock-limited engine loads, splash blended ethanol fuels with a higher ethanol percentage enabled higher engine thermal efficiency through allowing more advanced combustion phasing and less fuel enrichment for limiting the exhaust gas temperature under the upper limit of 850 °C, which was due to the synergic effects of higher RON and octane sensitivity, as well as better charge cooling. In comparison with octane sensitivity, RON was a more significant factor in improving engine thermal efficiency. Charge cooling reduced engine knock tendency through lowering the unburned gas temperature.

The characteristics of isooctane spray in the near field and far field were experimentally studied under various flash boiling conditions representing both low load and high load hot engine operation conditions. Closely coupled split injection strategy was also employed to study the influence of flash boiling on the primary breakup of split injections and the interaction between split injections. It was found that flash boiling considerably boosted the spray atomization, especially during the end of injection stage when a large amount of liquid fuel with low speed was observed. The interaction between split injections in liquid phase was significantly weakened under flash boiling condition due to the enhanced atomization but the interaction in gaseous phase was boosted because of the resultant quicker evaporation. The effect of dwell interval on the spray behavior under flash boiling condition was profound, causing significant variation for the delivered fuel mass and spray characteristics.

Gas-to-liquid (GTL) naphtha can be used as a gasoline blend component, and the challenge of its low octane rating is solved by using ethanol as an octane booster. However, currently there is little knowledge available about the performance of gasolines containing GTL naphtha in spark ignition engines. The objective of this work is to assess full load performance of gasoline fuels containing GTL naphtha in a modern spark ignition engine. In this study, four new gasoline fuels containing up to 23.5 vol.% GTL naphtha, and a standard EN228 gasoline fuel (reference fuel) were tested. These new gasoline fuels all had similar octane rating with that of the standard EN228 gasoline fuel. The experiments were conducted in an AVL single cylinder spark ignition research engine under full load conditions in the engine speed range of 1000–4500 rpm. Two modern engine configurations, a boosted direct injection (DI) and a port fuel injection (PFI), were used. A comprehensive thermodynamic analysis was carried out to correlate experiment data with fuel properties. The results show that, at the full load operating conditions the combustion characteristics and emissions of those gasoline fuels containing GTL naphtha were comparable to those of the standard EN228 gasoline fuel. Volumetric fuel consumption of fuels with high GTL naphtha content was higher due to the need of adding more ethanol to offset the reduced octane rating caused by GTL naphtha. Results also indicate that, compared to the conventional compliant E228 gasoline fuel, lower particulate emissions were observed in gasoline fuels containing up to 15.4 vol.% GTL naphtha.

Identifying a sustainable, practical and low-emission energy supply for modern transportation has always been a challenge for energy and automotive researchers. While electrification of the vehicle powertrain is a promising long-term energy supply solution, bio-ethanol is currently playing an important role as a short- and mid-term solution for the popular spark ignition (SI) engine. The questions of how to use ethanol more effectively as an octane booster, how much potential engine thermal efficiency gain can be achieved by using ethanol blends and what their impacts on the vehicle mileage range are have become highly relevant. In this paper, a critical review and discussion regarding these questions is provided. Firstly, studies regarding octane rating and octane index of gasoline fuels, and K value (a scaling factor for calculating octane index) for various SI engines are reviewed. Then, a review of the research octane number (RON), motor octane number (MON) and octane sensitivity for ethanol blends is reported. Three established models for predicting RON of ethanol blends are reviewed and compared. In addition, a simple RON prediction model proposed by the authors of this paper is provided. Parameters such as octane value and octane-added index (OAI) are proposed to describe the effectiveness of using ethanol as an octane booster. It is found that there exits an optimised ethanol blend ratio that gives the maximum octane value; and this optimised blend ratio is insensitive to the octane rating of the base gasoline. Secondly, the charge cooling effect of ethanol blends and its corresponding equivalent octane number are discussed and reviewed. Thirdly, engine thermal efficiency improvement due to increased compression ratios, which results from the octane index gain achieved by using ethanol blends, is reviewed. Finally, a discussion about the impact of ethanol blends on the vehicle mileage range is presented. The lower heating value of ethanol is about 33% lower than that of typical gasoline, leading to a reduction in the mileage range of the vehicle, however, improved engine thermal efficiency achieved by using ethanol blends can partially, or even fully, offset the negative impact of the lower calorific value on the mileage range.

This paper firstly proposed a novel HEV sizing method using the Chaos-enhanced Accelerated Particle Swarm Optimization (CAPSO) algorithm and secondly provided a demonstration on sizing a series hybrid electric powertrain with investigations of chaotic mapping strategies to achieve the global optimization. In this paper, the intelligent sizing of a series hybrid electric powertrain is formulated as an integer multi-objective optimization issue by modelling the powertrain system. The intelligent sizing mechanism based on APSO is then introduced, and 4 types of the most effective chaotic mapping strategy are investigated to upgrade the standard APSO into CAPSO algorithms for intelligent sizing. The evaluation of the intelligent sizing systems based on standard APSO and CAPSOs are then performed. The Monte Carlo analysis and reputation evaluation indicate that the CAPSO outperforms the standard APSO for finding the real optimal sizing result with much higher reputation, and CAPSO with logistic mapping strategy is the most effective algorithm for HEV powertrain components intelligent sizing. In addition, this paper also performs the sensitivity analysis and Pareto analysis to help engineers customize the intelligent sizing system.

An optical-based experimental study of the injector deposit effect on a multi-hole GDI injector was performed first. After carefully calibrating the spray model with the experiment data, a three-dimensional computational fluid dynamics (CFD) simulation was then carried out to study the deposit effect on the air/fuel mixture preparation process in an optical research GDI engine. Six different injection timings were used for full-cycle simulations. The numerical engine condition was at stoichiometric ratio, 1200 rpm and 150 bar injection pressure. The experimental results showed that injector deposit would lead to lower fuel mass flow rate, with 5.4%, 5.7% and 6.1% loss at 50, 100 and 150 bar respectively. Injector deposit resulted in longer penetration length and the effect displayed hole to hole difference. The maximum increment was observed for the ignition jets with 11.6% at 150 bar. Injector deposit led to higher droplet velocity and larger droplet size and the difference increased with injection pressure. For the air/fuel mixing simulation, the injector deposit led to more fuel impingement on the piston and cylinder walls, as well as a lower mean equivalence ratio during late injection events. The distorted spray pattern led to higher fuel stratification level. In very late injection cases, the injector deposit led to a very lean mixture near the spark plug which could result in unstable engine performance; while the rich regions at the cylinder sides could result in higher emissions. Comparison of computed results with PLIF (planar laser induced fluorescence) images provided a satisfactory validation for the model.

The flash boiling sprays in a single-cylinder optical gasoline direct injection (GDI) engine were studied using phase Doppler particle analyzer (PDPA) and high-speed photography. Initially, the factors which may influence the in-cylinder measurement reliability of PDPA were carefully examined under atmospheric conditions. Afterwards, engine experiments were conducted under idle and wide open throttle (WOT) conditions with the fuel temperature ranging from 20 °C to 90 °C. The results show that under idle operation, the spray collapsed towards the injector axis as the fuel temperature increased. At high fuel temperatures, the spray penetration increased so that the probability of fuel-wall impingement rises. As the fuel temperature increased from 20 °C to 60 °C, the AMD and SMD slumped by 43.6% and 33.2%, indicating the dramatic improvement in atomization quality. Concurrently, the droplet uniformity decreased sharply. As the temperature further increased to 90 °C, the AMD and SMD only dropped slightly, but the droplet uniformity became better. Under WOT operation, no distinct evidence of spray deformation was found except for the case at 90 °C. The AMD and SMD dropped steadily with the increase in fuel temperature, which is mainly attributed to the reduction in viscosity and surface tension. Besides, the droplet uniformity increased gradually along with the fuel temperature.

The effects of deposit on the spray macroscopic characteristics and droplet behaviour under flash boiling condition were investigated through high speed imaging and Phase Doppler Particle Analyzer (PDPA) techniques. Closely coupled split injection strategy was tried to alleviate the negative effect of deposit on spray characteristics. It was found that with single injection strategy, deposit led to smaller cone angle and longer penetration due to poorer atomization and dispersion. Deposit also resulted in larger droplet size by introducing large droplets and lowering the potential of further breakup into small ones. When split injection strategy was employed under non-flash boiling condition, the effects of deposit of on the over-penetration and the resultant high potential of impingement were alleviated, while the negative effect of deposit on droplet size was enhanced. However, when split injection was used under strong flash boiling condition, the negative influence of deposit on the spray over-penetration was significantly alleviated and the negative impact on the droplet size was almost eliminated although reduced potential for large droplets to further break up was still found. The employment of optimal split injection strategy is believed to be important for the alleviation of the adverse effect of deposit on the spray characteristics and the emissions.

The isooctane spray characteristics under various flash boiling conditions were studied with high speed imaging technique and Phase Doppler particle Analyser (PDPA) technique. The potential of closely coupled split injection strategy to alleviate fuel impingement and the corresponding spray characteristics were also investigated. It was found that flash boiling led to obvious collapse of spray and improved atomization. The increasing strength of flash boiling (excluding the transitional stage) resulted in increasing penetration and potential impingement. Stronger flash boiling caused smaller droplets and higher possibility for the droplets to further breakup. Closely coupled split injection strategy effectively reduced the overall spray penetration and the potential impingement. The flash boiling considerably weakened the collision between split injections and the interaction in liquid phase but strengthened the interaction in gas phase. The dwell interval exerted marginal effects on the penetration rate for each split injection event under flash boiling conditions due to the weakened interaction in liquid phase. By contrast, under non-flash boiling condition, the second split injection observably affected by the variation of dwell interval. Besides, split injection strategy resulted in larger droplet sizes than single injection strategy and the increasing flash boiling strength decreased the size difference between injection strategies.

2-Methyl tetrahydrofuran (2-MTHF) is one of the promising second-generation biofuel candidates, raising increasing interest because of the recent breakthrough in producing 2-MTHF from biomass. As a potential gasoline extender and renewable oxygenate, its high energy density and avoidance of competing with food make it attractive compared with ethanol. In the current work, the laminar burning characteristics of 2-MTHF-air mixtures are studied with varying equivalent ratios (0.88–1.43) and initial temperatures (333 K, 363 K and 393 K) at ambient pressure in a constant-volume vessel. The results are compared with ethanol and isooctane, a representative component in gasoline. The stretched flame speed, un-stretched flame speed, Markstein length, flame thickness, Markstein number, laminar burning velocity and burning flux are calculated and analyzed. The result shows that for most tests, the ranking of un-stretched flame propagation speed is ethanol, 2-MTHF and isooctane. The peaks of un-stretched flame speeds against varying equivalent ratios appear at Φ = 1.1–1.2 for three tested fuels. The Markstein length indicates that generally isooctane has the most diffusion-thermal stable flame than 2-MTHF and ethanol when Φ

Background: Few studies have examined the association between treatment given time and clinical outcomes, which is indeed of great importance to clinical management of coronavirus disease 2019 (COVID-19). We performed this study to explore whether early treatment brings favorable clinical outcomes. Methods: In this retrospective multicenter study, we included patients aged 18 to 87 years with confirmed COVID-19 on admission from 54 hospitals in nine provinces of China from 21 January to 10 March, 2020. Final date of follow-up was March 17, 2020. All patients were treated by Lung cleansing & detoxifying decoction combined with western medicine. Patients were divided into four groups according to the interval from the first date of onset of symptoms to the date of starting a treatment, i.e., ≤1 week group (≤7 days), 1-2 weeks group (>7 days and ≤14 days), 2-3 weeks group (>14 days and ≤21 days) and >3 weeks group (>21 days). Multivariable Cox proportional hazard ratio (HR) models were used to estimate unadjusted and adjusted HRs and 95% confidence intervals (CIs) for the association between the treatment given time and clinical outcomes (time to recovery, days of viral shedding, duration of hospital stay, course of disease, fever and CT images). Findings: Of the 782 patients (median age was 46 years old, and 405 (52%) were male), there were 321 (41%) patients in ≤1 week group, 221 (28%) in 1-2 weeks group, 123 (16%) in 2-3 weeks group and 117 (15%) in >3 weeks group. Compared to patients in later treatment group (greater than 3 weeks), patients in earlier treatment groups of less than 1 week, 1 to 2 weeks, or 2 to 3 weeks had higher likelihood of recovery, with adjusted HR (95% CI) of 3.81 (2.65-5.48), 2.63 (1.86-3.73) and 1.92 (1.34-2.75), respectively. The median days of viral shedding was 13 days and 12 days in 2-3 weeks group and 3 weeks group (P=0.0137). The median course of disease decreased from 34 days to 24 days, 21 days and 18 days when treatment was given every one week in advance compared to that was given later than 3 weeks from the onset of symptoms (P

With recent advances in digital microscopy, quantitative analysis of pathology images has become important in disease diagnosis as well as in understanding the underlying reasons. Digital whole slide images (WSI) are typically obtained from a biopsy slide using a high-resolution slide scanner. The hematoxylin and eosin (H&E) stain is typically used to stain the slides. However, immunospecific stains such as MART-1 (for melanoma) and PD-L1 (for lung cancer) are also sometimes used to validate detection. In advanced stages, cancer cells spread to lymph nodes through the lymph vessels. Therefore, a lymph node biopsy is typically done by doctors to determine if the cancer cells have invaded the lymph node system. High-resolution WSIs typically have very large size, in the order of a billion pixels. Hence, image analysis and diagnosis (quantitative as well as qualitative) is expected to take significant time. In this chapter, we present the state of the art on computer-aided diagnosis and grading of skin cancer/melanoma based on histopathology. The techniques generally include traditional image analysis modules such as preprocessing, segmentation, feature extraction, and classifications. Recently, deep learning techniques such as SegNet and U-Net have been used successfully in histopathological image analysis. The detailed implementation of our works on melanoma detection and proliferation index calculation using deep learning networks is presented and compared with traditional feature-based techniques. Experimental results show superior performance by the deep learning networks.

Background: Novel coronavirus pneumonia (NCP) is often changing rapidly and fatal. Early detection and early triage of coronavirus disease 2019 (Covid-19) is the key to success management of the disease. An easily obtainable yet accurate variable for both diagnosis and prognosis is urgently needed. We aim to report predictive Value of the Neutrophil-to-Lymphocyte Ratio(NLR) for diagnosis and worse clinical course of the COVID-19, which have not been well demonstrated. Methods: Our study consisted of two stages, at the first stage, a retrospective, single-center, cohort study including was conducted in Heilongjiang, on admission, demographic, clinical, and laboratory data were collected and compared between patients with COVID-19 and patients with non COVID-19; we used multivariable logistic regression methods to explore the risk factors associated with COVID-19;A receiver operating characteristic(ROC) analysis was conducted to calculate the area under the curve(AUC) to assess predictive value of NLR for diagnosis of COVID 19. At the second stage, we conducted retrospective, multi-center and large sample study in 43 hospitals from ten provinces of China, COVID-19 patients with laboratory-confirmed divided into three groups including mild cases, ordinary cases and severe cases. Multivariate logistic regression methods were used to identify the risk factors for the deterioration of COVID-19, along with, a receiver operating characteristic (ROC) curve was also drawn to assess impact on the clinical course of the COVID-19. Findings: We recruited a total of 635 patients with COVID-19 and 27 cases with non COVID-19(Viral pneumonia) from 28 January to 25 February. A total of 88 cases were enrolled with a retrospective, single-center, cohort study from Heilongjiang province, of these, COVID-19 cases were 61(69%) and non COVID-19 cases were 27(31%). On admission, fever (69%) was the most common symptoms, cough (56%) and fatigue(53%). An average(SD) of NLR of COVID-19 patients and non- COVID-19 patients were3.48±2.04 and 2.21±1.14, respectively. multivariable regression showed increasing odds of COVID-19 patients associated with NLR(odds ratio 1.752, 95% CI 1.111-2.763, per 1 unit increase; p=0.016). In addition, the area under the curve (AUC) of NLR was 0.707 and cutoff value was 2.22. At the second stage, 635 patients with COVID were enrolled with a retrospective, multi-center, large sample study in the 43 settings from 10 provinces, of these, mild case were 86(14%), ordinary cases [486(76%)],severe cases[63(10%)], common symptoms was at onset of disease were cough[356(56%)], an average of NLR of 635 patients was 4.04±4.68, and elevated NLR with the deterioration of clinical course[mild case(2.73±2.28), ordinary cases(3.58±3.07), severe cases(9.38±10.52), P

Additional file 1.

BackgroundA worldwide outbreak of coronavirus disease (COVID-19), since 2019, has brought a disaster to people all over the world. Many researchers carried out clinical epidemiological studies on patients with COVID-19 previously, but risk factors for patients with different levels of severity are still unclear.Methods562 patients with laboratory-confirmed COVID-19 from 12 hospitals in China were included in this retrospective study. Related clinical information, therapies, and imaging data were extracted from electronic medical records and compared between patients with severe and non-severe status. We explored the risk factors associated with different severity of COVID-19 patients by logistic regression methods.ResultsBased on the guideline we cited, 509 patients were classified as non-severe and 53 were severe. The age range of whom was 5–87 years, with a median age of 47 (IQR 35.0–57.0). And the elderly patients (older than 60 years old) in non-severe group were more likely to suffer from fever and asthma, accompanied by higher level of D-dimer, red blood cell distribution width and low-density lipoprotein. Furthermore, we found that the liver and kidney function of male patients was worse than that of female patients in both severe and non-severe groups with different age levels, while the severe females had faster ESR and lower inflammatory markers. Of major laboratory markers in non-severe cases, baseline albumin and the lymphocyte percentage were higher, while the white blood cell and the neutrophil count were lower. In addition, severe patients were more likely to be accompanied by an increase in cystatin C, mean hemoglobin level and a decrease in oxygen saturation. Besides that, advanced age and indicators such as count of white blood cell, glucose were proved to be the most common risk factors preventing COVID-19 patients from aggravating.ConclusionThe potential risk factors found in our study have shown great significance to prevent COVID-19 patients from aggravating and turning to critical cases during treatment. Meanwhile, focusing on gender and age factors in groups with different severity of COVID-19, and paying more attention to specific clinical symptoms and characteristics, could improve efficacy of personalized intervention to treat COVID-19 effectively.

OBJECTIVE: To observe the disease spectrum of the parotid region lesions in children, and clarify the outcome and prognosis of the disease by analyzing of clinical data. METHOD: The basic information, clinical symptoms, diagnosis results, treatment, prognosis and follow-up of 170 cases with parotid region lesions were analyzed. RESULT: Among 170 cases of the parotid region lesions, 83 cases(48.82%) were congenital disease, 62 cases(36.47%) were vascular mass, 17 cases(10.00%) were benign or malignant tumor, and 8 cases(4.71%) were infectious disease; 108 cases of the patients were treated with surgery, 34 of them were treated with local bleomycin injection while 28 cases were treated with both surgery and local bleomycin injection. Two cases was cured by reoperation after recurrence and 1 case had facial paralysis but recovered after 3 months of follow-up. CONCLUSION: The most common diseases of parotid region lesions in children were congenital disease and vascular mass. Surgery combined with bleomycin local treatment is the main therapy in parotid area and has achieved remarkable results. Oral propranolol has certain therapeutic value for parotid region hemangioma.

Histological Gleason grading of tumor patterns is one of the most powerful prognostic predictors in prostate cancer. However, manual analysis and grading performed by pathologists are typically subjective and time-consuming. In this paper, we present an automatic technique for Gleason grading of prostate cancer from H&E stained whole slide pathology images using a set of novel completed and statistical local binary pattern (CSLBP) descriptors. First, the technique divides the whole slide image (WSI) into a set of small image tiles, where salient tumor tiles with high nuclei densities are selected for analysis. The CSLBP texture features that encode pixel intensity variations from circularly surrounding neighborhoods are extracted from salient image tiles to characterize different Gleason patterns. Finally, the CSLBP texture features computed from all tiles are integrated and utilized by the multi-class support vector machine (SVM) that assigns patient slides with different Gleason scores such as 6, 7, or $\geq$ ≥ 8. Experiments have been performed on 312 different patient cases selected from the cancer genome atlas (TCGA) and have achieved superior performances over state-of-the-art texture descriptors and baseline methods including deep learning models for prostate cancer Gleason grading.

Particulate and vapor phase emissions in the diluted exhaust of a light-duty diesel engine designed for Euro 5 application have been sampled. The engine was operated in three modes, and samples were collected from the exhaust without aftertreatment but also with aftertreatment by an exhaust oxidation catalyst and particle filter. The samples were analyzed by two-dimensional gas chromatography with time-of-flight mass spectral detection. The results show overall removal efficiencies for the organic compound mass by the combination of oxidation catalyst and particle filter of 50, 56, and 74% for the high-speed/high-load, low-speed/low-load, and high-speed/low-load conditions respectively. The results are clearly indicative of substantial repartitioning of the particulate and vapor components within the abatement devices and show an apparently reduced efficiency for the removal of high-molecular-weight alkanes under high-speed/high-load conditions relative to lower-molecular-weight compounds, although this may be due to alkane formation by thermocracking of other species. A notable feature is the presence of oxygenated compounds in the emissions, which are not present in the fuel. These are increased under high-speed/high-load conditions, and the results suggest the formation in the aftertreatment devices as well as in the combustion process.

Hydrocarbon fuel reforming has been proven useful for producing hydrogen that is utilized on road vehicles, but it is associated with reaction mechanism and catalyst characterization. In this study, a reduced mechanism for n-heptane/toluene reforming over an advanced Pt/Rh TWC is adopted to investigate the effects of the reaction conditions on H2 and CO concentrations. The physical and chemical properties of the advanced catalyst are examined using SEM, XRD and XPS analyses. The contrasted experiments are conducted to study the composition variation tendency of the reforming reactor gas product. The results show that the POX reaction is most likely to occur considering the stoichiometric ratio of H2/CO, and other reactions are SR or ATR. The coke formation and carbon deposition occur on the catalyst surface, and the diffraction peaks corresponding to the metallic Pt are observed, while no obvious peaks characteristic of Rh are detected. The characteristics of the concentration trend of n-heptane/toluene reforming can represent H2 and CO yield features of diesel reforming in a way, nevertheless, the difference of the average H2 and CO concentration is remarkable.

Recent studies based on deep learning on pathology images have shown the potential prognostic role of Tumor-infiltrating lymphocytes (TILs) in many cancer types. In general, most of these studies focused on detecting, quantifying and identifying TILs and spatial organization in entire whole slide images (WSIs) including both non-cancer and cancer regions. In this work, we hypothesize that TILs present in cancer regions not entire WSIs could have prognostic values. Here we present an automatic technique based on convolutional neural networks (CNN) that detects both cancer and TILs regions, and explores fraction and spatial organization of TILs in the detected cancer region from WSIs. A novel set of quantitative histological image features reflecting TILs fraction and spatial organization is extracted and used to stratify patients with distinct survival outcomes. In experiments using 277 different patient pathology slides selected from The Cancer Genome Atlas (TCGA) bladder cancer cohort, we show that bladder cancer patient survival is significantly correlated with our designed TIL-related image features, with a log-rank test p value below 0.05. Our method is extensible to histopathology images of other organs for predicting patient survival via TIL analysis.

The analysis of in-cylinder combustion temperatures using flame image processing technology is reliable. This method can accurately, intuitively, and in real time obtain the temperature field distribution law of the combustion flame in the cylinder, so we can more deeply understand the characteristics of the combustion process of internal combustion engines. In this paper, a high-speed charge-coupled device (CCD) camera is used to record an in-cylinder combustion image, which is calculated and corrected according to the principle of three primary color temperature measurement, and the temperature field distribution of the combustion flame in the diesel engine cylinder is analyzed in detail. In addition, the temperature of the typical combustion flame images under the open-cycle and closed cycle conditions is compared by the CMS2002 measurement and MATLAB program, respectively. The results show that the accuracy of the MATLAB program is acceptable in general but not entirely acceptable in a few ways.

SUMMARY OBJECTIVE To investigate the relations of T lymphocytes, cytokines, immunoglobulin E, and nitric oxide with otitis media with effusion (OME) in children and their clinical significances. METHODS Fifty children with OME treated in our hospital were enrolled in the study (observation group). Fifty healthy children were selected as control. The percentages of CD4+ and CD8+ T lymphocyte and CD4+/CD8+ ratio in peripheral blood, and the levels of cytokine (IL)-2, IL-4, IL-6, immunoglobulin E (IgE) and nitric oxide (NO) in peripheral blood and middle ear effusion (MEE) in both groups were detected. The correlations of these indexes with OME were analyzed. RESULTS The percentage of peripheral blood CD4+ and CD8+ levels, CD4+/CD8 ratio, IgE, and NO levels in the observation group were significantly higher than those in the control group (P < 0.01). In the observation group, the IL-2 and IL-6 levels, and IgE and NO levels in the MEE were significantly higher than those in peripheral blood (P < 0.01). In addition, in the observation group, the MEE IL-2 and IL-6 levels were positively correlated with peripheral blood CD4+/CD8+ ratio, respectively r = 0.366, P = 0.009; r = 0.334, P = 0.018. CONCLUSIONS The levels of peripheral blood CD4+ and CD8+ lymphocytes and MEE IL-2, IL-6, IgE, and NO levels are increased in children with OME. These indexes have provided significant clues for the diagnosis of OME in children. RESUMO OBJETIVO Investigar as relações entre linfócitos T, citocinas, imunoglobulina E e óxido nítrico e a otite média com efusão (OME) em crianças e sua significância clínica. MÉTODOS Cinquenta crianças com OME tratadas em nosso hospital foram incluídas no estudo (grupo de observação). Selecionamos também 50 crianças saudáveis como controle. As porcentagens de linfócitos T CD4 + e CD8 + e a razão CD4+/CD8+ no sangue periférico, além dos níveis das citocinas IL-2, IL-4, IL-6, imunoglobulina E (IgE) e óxido nítrico (NO) no sangue periférico e de efusão no ouvido médio (MEE) de ambos os grupos foram medidos. A correlação desses índices com a OME foi analisada. RESULTADOS A porcentagem dos níveis de CD4+ e CD8 +, da razão CD4+/CD8+, de IgE e NO no sangue periférico do grupo de observação foram significativamente maiores do que no grupo controle (P < 0,01). No grupo de observação, os níveis de IL-2 e IL-6, IgE e NO em MEE foram significativamente maiores do que no sangue periférico (P < 0,01). Além disso, no grupo de observação, foi encontrada uma correlação positiva entre os níveis de IL-2 e IL-6 em MEE e a razão de CD4+/CD8+no sangue periférico, respectivamente, r = 0,366, P = 0,009; r = 0,334, P = 0,018. CONCLUSÃO Os níveis de linfócitos CD4 + e CD8 + no sangue periférico e IL-2, IL-6, IgE e NO em MEE são mais altos em crianças com OME. Esses índices forneceram evidências valiosas para o diagnóstico de OME em crianças.