Electricity powering combustion: hydrogen engines

Hydrogen is ameans to chemically store energy. It can be used to buffer energy in a society increasingly relying on renewable but intermittent energy or as an energy vector for sustainable transportation. It is also attractive for its potential to power vehicles with (near-) zero tailpipe emissions. The use of hydrogen as an energy carrier for transport applications is mostly associated with fuel cells. However, hydrogen can also be used in an internal combustion engine (ICE). When converted to or designed for hydrogen operation, an ICE can attain high power output, high efficiency and ultra low emissions. Also, because of the possibility of bi-fuel operation, the hydrogen engine can act as an accelerator for building up a hydrogen infrastructure. The properties of hydrogen are quite different from the presently used hydrocarbon fuels, which is reflected in the design and operation of a hydrogen fueled ICE (H2ICE). These characteristics also result in more flexibility in engine control strategies and thus more routes for engine optimization. This article describes the most characteristic features of H2ICEs, the current state of H2ICE research and demonstration, and the future prospects

HLA-DRB1 and DQB1 alleles in Japanese type 1 autoimmune hepatitis: The predisposing role of the DR4/DR8 heterozygous genotype

ObjectiveAutoimmune hepatitis (AIH) is a chronic progressive liver disease. AIH is composed predominantly of type 1 in Japanese populations. The genetic and environmental factors are associated with the pathogenesis of AIH. HLA-DRB1*03:01 and *04:01 are associated with type 1 AIH in European and *04:05 in Japanese populations. Here, we conducted an HLA association study in order to find HLA alleles or haplotypes predisposing or protective for Japanese AIH.MethodsHLA-DRB1 and DQB1 genotyping of 360 type 1 AIH patients and 1026 healthy controls was performed.ResultsThe predisposing association of DRB1*04:01 (P = 0.0006, corrected P [Pc] = 0.0193, odds ratio [OR] 2.97, 95% confidence interval [CI] 1.62–5.43), DRB1*04:05 (P = 1.89×10−21, Pc = 5.86×10−20, OR 3.41, 95% CI 2.65–4.38), and DQB1*04:01 (P = 4.66×10−18, Pc = 6.99×10−17, OR 3.89, 95% CI 2.84–5.33) and the protective association of DRB1*13:02 (P = 0.0003, Pc = 0.0080, OR 0.48, 95% CI 0.32–0.72) with Japanese type 1 AIH were observed. An association of the DR4/DR8 heterozygous genotype with Japanese AIH was identified for the first time (P = 3.12×10−9, OR 3.52, 95% CI 2.34–5.29). Susceptible diplotypes were DRB1*04:05-DQB1*04:01/DRB1*08:02-DQB1*03:02 (P = 0.0004, OR 24.77, 95% CI 1.45–424.31) and DRB1*04:05-DQB1*04:01/DRB1*08:03-DQB1*06:01 (P = 1.18×10−6, OR 10.64, 95% CI 3.19–35.46). Serum levels of Immunoglobulin G and Immunoglobulin M, International Autoimmune Hepatitis Group score, positive rate of anti-smooth muscle antibodies, and the rate of definite AIH were higher in AIH patients with DRB1*04:05 than without.ConclusionsThe important roles of specific combinations of DRB1 and DQB1 alleles or haplotypes in the pathogenesis of type 1 AIH were suggested. The association of DR4/DR8 heterozygous genotype suggested the pathologic importance of trans-complementing DQα-β heterodimer molecules encoded by DQA1 allele of one haplotype and the DQB1 allele of the other haplotype, as it was proposed in the HLA association studies of Type 1 diabetes

Lack of association between the CARD10 rs6000782 polymorphism and type 1 autoimmune hepatitis in a Japanese population

Background: Previous genome-wide association studies have evaluated the impact of common genetic variants and identified several non-HLA risk loci associated with autoimmune liver diseases. More recent genome-wide association studies and replication analyses reported an association between variants of the CARD10 polymorphism rs6000782 and risk of type 1 autoimmune hepatitis (AIH). In this case-control study, we genotyped 326 Japanese AIH patients and 214 control subjects. Results: Genomic DNA from 540 individuals of Japanese origin, including 326 patients with type-1 AIH and 214 healthy controls, was analyzed for two single nucleotide polymorphisms (SNPs) in the CARD10 gene. We selected CARD10 rs6000782 SNPs and genotyped these using PCR-RFLP method and direct sequencing. The Chi square test revealed that the rs6000782 variant alle (c) was not associated with the susceptibility for AIH in a Japanese population [p = 0.376, odds ratio (OR) 1.271, 95 % confidence interval (CI) 0.747-2.161] in an allele model. Our data also showed that CARD10 rs6000782 variants were not associated with AIH or with the clinical parameters of AIH. Conclusions: In this study we examined an association between rs6000782 SNPs in the CARD10 gene and type-1 AIH. Results showed no significant association of rs62000782 with type-1 AIH in a Japanese population. This study demonstrated no association between CARD10 rs6000782 variants and AIH in a Japanese population

Effect of load control strategies for methanol fueled vehicle on drive cycle emissions

The use of methanol as spark-ignition engine fuel can help to increase energy security and offers the prospect of carbon neutral transport. Methanol’s properties enable considerable improvements in engine performance, efficiency and CO2 emissions compared to gasoline operation. Previous research is reported that both flex-fuel and dedicated methanol engines can benefit from an operating strategy employing exhaust gas recirculation to control the load while leaving the throttle wide open (WOT). The current paper presents follow-up work to determine to what extent these advantages still stand over an entire drive cycle by vehicle simulation software. The CO2 and NOx emissions of methanol vehicle with hybrid system are estimated to be 85 g/km and 0.06 g/km at NEDC, 149g/mi and 0.07 g/mi at FTP. Thus our results indicate that the WOT-EGR strategy with high compression ratio methanol fuelled engine represents an interesting alternative powertrain to conventional gasoline/diesel vehicles

Effect of Nonlinear Spring Characteristics on the Efficiency of Free-Piston Engine Generator

Piston motion is an important factor in improving the energy conversion efficiency of free-piston engine generators (FPEGs), and an air cylinder is an important component affecting piston motion. In this study, the effect of the air cylinder specifications on the piston drive frequency and energy conversion efficiency is clarified. By considering that the repulsion force of an air cylinder is nonlinear, the main factors that change the piston drive frequency were investigated by simulation. In addition, a piston drive frequency diagram was drawn based on the top surface area of the air cylinder and the compression ratio to discuss the effect of the air cylinder specifications on the piston drive frequency. The results indicate that the air cylinder specifications affect the piston drive frequency and generation force of a linear machine. Moreover, the structure of the air cylinder and the constraints on the maximum generation force of the linear machine narrow the possible operating range in the piston drive frequency. The air cylinder specifications based on the piston drive frequency diagram improved the FPEG energy conversion efficiency by 0.5%

Operation Range of Intermittent Velocity Control for Improving Top-Dead-Center Accuracy in Dual-Sided Free-Piston Engine Linear Generator

A free-piston engine linear generator (FPEG) is constructed by combining a reciprocating internal combustion engine and a linear generator. FPEG is required to improve both the accuracy of the top-dead-center (TDC) positioning considering frequent combustion fluctuations and the reduction of power consumption. This paper confirms the influence of intermittent velocity control on power running suppression and TDC position deviation in a dual-cylinder FPEG. Intermittent velocity control is a simple method, which consists of repeatedly turning the speed control on and off. The experimental results of the glow engine indicate that this control suppresses power consumption and enables continuous combustion. The setting range for intermittent speed control, which continues operation only through regenerative operation, must be determined by considering the gain value. In addition, this paper explains the effects of the control range of intermittent velocity control on power generation efficiency, piston motion frequency, and TDC position deviation in the dual-cylinder FPEG. Increasing the range ratio of intermittent speed control improves power generation efficiency, but it also increases the standard deviation of TDC position

Association of soluble T cell immunoglobulin domain and mucin-3 (sTIM-3) and mac-2 binding protein glycosylation isomer (M2BPGi) in patients with autoimmune hepatitis.

BackgroundAutoimmune hepatitis (AIH) is a disorder of unknown etiology in which immune-mediated liver injury progress to cirrhosis or hepatocellular carcinoma (HCC). The aim of the present study was to determine whether circulating soluble TIM3 (sTIM3) is elevated in patients with AIH patients and whether sTIM-3 levels are associated with clinical parameters of AIH.MethodsWe enrolled 123 Japanese patients with AIH who were identified from the National Hospital Organization-AIH-liver-network database, as well as 32 patients with chronic hepatitis C (CHC), 30 patients with primary biliary cholangitis (PBC) and healthy control subjects. Serum sTIM-3 concentrations were quantified by ELISA.ResultsSerum levels of sTIM-3 were significantly higher in AIH patients (median 4865 pg/ml; [interquartile range (IQR); 3122-7471]) compared to those in CHC (1026 pg/ml [IQR: 806-1283] pConclusionsCirculating sTIM-3 levels were elevated in AIH patients and are associated with AIH disease activity and AIH-related liver damage. These findings indicate that serum sTIM-3 correlated with disease status of AIH and could be useful biomarkers to detect autoimmune-mediated liver injury. Our data suggest a possible link between the TIM-3/GAL-9 pathway and AIH severity or phenotype, and further investigations of the TIM-3 pathway and AIH pathophysiology is warranted