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Current advances in genome sequencing of common wheat and its ancestral species
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Finding a common ground for RCM experiments. Part A: On the influences of facility effects regarding the reliability of experimental validations
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Finding a common ground for RCM experiments. Part B: Benchmark study on ethanol ignition
Rapid compression machines (RCMs) are widely used to investigate gas phase reaction kinetics of various kind of fuels at application relevant conditions. In principle, the operation of an RCM is based on the idea of compressing a homogenous pre-mixed fuel-air mixture by a piston. Usually creviced pistons ensure a homogenous adiabatic core in the center of the reaction chamber which permits the assumption of an isentropic relation between the measured pressure and gas temperature. Despite the ideal core gas compression, non-ideal effects such as heat loss, differences in the compression behavior, and ultimately non-standardized design and operation of rapid compression machines lead to different experimental results in different facilities at nominally the same end of compression conditions. In this study ignition delay times of ethanol are investigated at four different conditions in five independent RCMs. As expected, the raw results of the different facilities indeed show notable differences at the same end of compression conditions. However, according to the adiabatic core hypothesis the agreement between kinetic simulations and experiments should be consistent for all facilities provided that the facility effects are correctly accounted for. To elaborate upon this hypothesis, a kinetic mechanism is optimized to reflect the experimental results of all facilities. In the end, the optimized mechanism predicts all experimental data within the expected uncertainty. This confirms the reliability of RCM experiments for kinetic investigations and the validity of the effective volume approach in simulating RCM data.
A first principles study of commonly observed planar defects in Ti/TiB system
Here, TiB exhibits a hexagonal cross-section with growth faults on (1 0 0) planes and contains B27-B f bicrystals. The hexagonal cross-section is presently explained by surface free energy minimization principle. We show that interfacial energy calculations explain the longer (1 0 0) facet compared to (1 0 1) type facets whereas free surface energy arguments do not provide the true picture. No quantitative explanation of stacking faults and B27-B f interfaces in TiB exists. We show that the low formation energy of stacking faults and B27-B f interfaces explain their abundance. The low energy barrier for B f formation is shown to be responsible for their presence in TiB.
Designing interagency responses to wicked problems: Creating a common, cross-agency understanding
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Impacts of common faults on an air conditioner with a microtube condenser and analysis of fault characteristic features
Split system air conditioners are widely used to cool residential buildings, because of their low cost and simplicity. However, their efficiency is impacted by installation faults, which include: improper refrigerant charge (undercharge or overcharge), improper evaporator airflow, liquid line restrictions (LL), and the presence of non-condensable gas (NC) in the refrigerant. No known previously published research has studied the effect of these four faults on a system equipped with a microtube condenser, which has smaller tube size than a traditional condenser and therefore holds less refrigerant charge, but has a different configuration than a microchannel. Furthermore, very few have studied the impacts of LL and NC. Herein this paper describes laboratory fault tests of a microtube-equipped system, compares the fault impacts with those of a traditional system, and considers the characteristic fault features. The tested system uses R-410A refrigerant and has a scroll compressor, a fixed orifice expansion device, and two fin-tube heat exchangers. The tests were carried out under steady operation with a range of fault intensities and operating conditions. The microtube system’s performance degradation from faults is similar to systems with traditional heat exchangers, despite the reduced capacity to hold refrigerant charge.
Personal exposure to fine particles (PM2.5) and respiratory inflammation of common residents in Hong Kong
Highlights: • Personal PM{sub 2.5} monitoring from 46 healthy adults with up to 6 repeated measurements were conducted. • Personal PM{sub 2.5} exposures were higher than ambient levels monitored by stations. • Mixed-effects model was applied to assess the relationship between air pollutants exposure and biomarker. • Significant associations were observed for the increased FeNO with personal exposure to PM{sub 2.5} and c-PAHs. Given the lack of research on the personal exposure to fine particles (PM{sub 2.5}) in Hong Kong, we examined the association between short-term personal exposure to PM{sub 2.5} and their constituents and inflammation in exhaled breath in a sample of healthy adult residents.
An experimental investigation of the combustion process and the injection strategy of a heavy-duty diesel engine equipped with a common rail fuel injection system
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A fluid mechanics explanation of the effectiveness of common materials for respiratory masks
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Comparison of 2 Common Radiation Therapy Techniques for Definitive Treatment of Small Cell Lung Cancer
Purpose: Two choices are widely used for radiation delivery, 3-dimensional conformal radiation therapy (3DCRT) and intensity modulated radiation therapy (IMRT). No randomized comparisons have been conducted in the setting of lung cancer, but theoretical concerns suggest that IMRT may negatively impact disease control. We analyzed a large cohort of limited-stage small-cell lung cancer (LS-SCLC) patients treated before and after institutional conversion from 3DCRT to IMRT to compare outcomes. Methods and Materials: Patients with LS-SCLC treated with definitive radiation at our institution between 2000 and 2009 were retrospectively reviewed. Both multivariable Cox regression and propensity score matching were used to compare oncologic outcomes of 3DCRT and IMRT in the context of other clinically relevant covariables. Acute and chronic toxicities associated with the 2 techniques were compared using Fisher exact and log–rank tests, respectively. Results: A total of 223 patients were treated during the study period, with 119 receiving 3DCRT and 104 receiving IMRT. Their median age was 64 years (range, 39-90 years). Median follow-up times for 3DCRT and IMRT were 27 months (range, 2-147 months) and 22 months (range, 4-83 months), respectively. Radiation modality was not associated with differences in overall survival or disease-free survival in either multivariable or propensity score-matched analyses. IMRT patients required significantly fewer percutaneous feeding tube placements (5% vs 17%, respectively, P=.005). Conclusions: IMRT was not associated with worse oncologic outcomes than those of 3DCRT. IMRT was associated with a lower rate of esophagitis-related percutaneous feeding tube placements.
Tumor Cells Surviving Exposure to Proton or Photon Radiation Share a Common Immunogenic Modulation Signature, Rendering Them More Sensitive to T Cell–Mediated Killing
Purpose: To provide the foundation for combining immunotherapy to induce tumor antigen–specific T cells with proton radiation therapy to exploit the activity of those T cells. Methods and Materials: Using cell lines of tumors frequently treated with proton radiation, such as prostate, breast, lung, and chordoma, we examined the effect of proton radiation on the viability and induction of immunogenic modulation in tumor cells by flow cytometric and immunofluorescent analysis of surface phenotype and the functional immune consequences. Results: These studies show for the first time that (1) proton and photon radiation induced comparable up-regulation of surface molecules involved in immune recognition (histocompatibility leukocyte antigen, intercellular adhesion molecule 1, and the tumor-associated antigens carcinoembryonic antigen and mucin 1); (2) proton radiation mediated calreticulin cell-surface expression, increasing sensitivity to cytotoxic T-lymphocyte killing of tumor cells; and (3) cancer stem cells, which are resistant to the direct cytolytic activity of proton radiation, nonetheless up-regulated calreticulin after radiation in a manner similar to non-cancer stem cells. Conclusions: These findings offer a rationale for the use of proton radiation in combination with immunotherapy, including for patients who have failed radiation therapy alone or have limited treatment options.
ERAP1 binds peptide C-termini of different sequences and/or lengths by a common recognition mechanis
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