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1.
Several immune checkpoint molecules and immune targets in leukemic cells have been investigated. Recent studies have suggested the potential clinical benefits of immuno-oncology (IO) therapy against acute myeloid leukemia (AML), especially targeting CD33, CD123, and CLL-1, as well as immune checkpoint inhibitors (e.g., anti-PD (programmed cell death)-1 and anti-CTLA4 (cytotoxic T-lymphocyte-associated protein 4) antibodies) with or without conventional chemotherapy. Early-phase clinical trials of chimeric antigen receptor (CAR)-T or natural killer (NK) cells for relapsed/refractory AML showed complete remission (CR) or marked reduction of marrow blasts in a few enrolled patients. Bi-/tri-specific antibodies (e.g., bispecific T-cell engager (BiTE) and dual-affinity retargeting (DART)) exhibited 11–67% CR rates with 13–78% risk of cytokine-releasing syndrome (CRS). Conventional chemotherapy in combination with anti-PD-1/anti-CTLA4 antibody for relapsed/refractory AML showed 10–36% CR rates with 7–24 month-long median survival. The current advantages of IO therapy in the field of AML are summarized herein. However, although cancer vaccination should be included in the concept of IO therapy, it is not mentioned in this review because of the paucity of relevant evidence.  相似文献   
2.
Experiments on methanogenic digestion using high concentrations of mixed substrate were conducted. The major intermediate products of anaerobic digestion such as acetic, propionic and butyric acids were mixed in a ratio of 2:1:1 (COD basis), respectively, and used as a substrate for feeding into continuous-flow chemostat reactors maintained at 35°C. These reactors were operated stably at higher feed substrate concentrations and shorter hydraulic retention times (HRT) than those of using a single component of volatile fatty acids as a substrate. At an HRT of 4.43 days, the methanogenesis occurred normally up to a feed substrate concentration of 70,000 mg COD I−1. At a feed substrate concentration of 20,000 mg COD I−1, the methanogenesis occurred normally up to an HRT of 2.91 days and the minimum SRT for microbial populations was calculated to be 2.42 days. An increase in feed substrate concentration adversely affected the propionate degradation strikingly, while a decrease in HRT significantly adversely affected the acetate and propionate degradation. The methane production was 0.301 g−1 COD utilized, and it was independent of the feed substrate concentration and HRT. Bacilli were predominant in all reactors, but sarcinae appeared in the reactors with high feed substrate concentrations and short HRTs. Phenomena in digester failure due to methanogen washout were also observed.  相似文献   
3.
To survive worldwide competitions of research and development in the current rapid increase of information, decision-makers and researchers need to be supported to find promising research fields and papers. But finding those fields from an available data in too much heavy flood of information becomes difficult. We aim to develop a methodology supporting to find emerging leading papers with a bibliometric approach. The analyses in this work are about four academic domains using our time transition analysis. In the time transition analysis, after citation networks are constructed, centralities of each paper are calculated and their changes are tracked. Then, the centralities are plotted, and the features of the leading papers are extracted. Based on the features, we proposed ways to detect the leading papers by focusing on in-degree centrality and its transition. This work will contribute to finding the leading paper, and it is useful for decision-makers and researchers to decide the worthy research topic to invest their resources.  相似文献   
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5.
Aiming at enhancing H2 production in water gas shift (WGS) for fuel cell application, a small amount of oxygen was added to WGS reaction toward oxygen-enhanced water gas shift (OWGS) on ceria-supported bimetallic Pd–Cu and Pt–Cu catalysts. Both CO conversion and H2 yield were found to increase by the oxygen addition. The remarkable enhancement of H2 production by O2 addition in short contact time was attributed to the enhanced shift reaction, rather than the oxidation of CO on catalyst surface. The strong dependence of H2 production rate on CO concentration in OWGS kinetic study suggested O2 lowers the CO surface coverage. It was proposed that O2 breaks down the domain structure of chemisorbed CO into smaller domains to increase the chance for coreactant (H2O) to participate in the reaction and the heat of exothermic surface reaction helping to enhance WGS kinetics. Pt–Cu and Pd–Cu bimetallic catalysts were found to be superior to monometallic catalysts for both CO conversion and H2 production for OWGS at 300 °C or lower, while the superiority of bimetallic catalysts was not as pronounced in WGS. These catalytic properties were correlated with the structure of the bimetallic catalysts. EXAFS spectra indicated that Cu forms alloys with Pt and with Pd. TPR demonstrated the strong interaction between the two metals causing the reduction temperature of Cu to decrease upon Pd or Pt addition. The transient pulse desorption rate of CO2 from Pd–Cu supported on CeO2 is faster than that of Pd, suggesting the presence of Cu in Pd–Cu facilitate CO2 desorption from Pd catalyst. The oxygen storage capacity (OSC) of CeO2 in the bimetallic catalysts indicates that Cu is much less pyrophoric in the bimetallic catalysts due to lower O2 uptake compared to monometallic Cu. These significant changes in structure and electronic properties of the bimetallic catalysts are the result of highly dispersed Pt or Pd in the Cu nanoparticles.  相似文献   
6.
The relationship between internal fracture due to high-pressure hydrogen decompression and microstructure of ethylene–propylene–diene–methylene linkage (EPDM) rubber was investigated by atomic force microscopy (AFM). Nanoscale line-like structures were observed in an unexposed specimen, and their number and length increased with hydrogen exposure. This result implies that the structure of the unfilled EPDM rubber is inhomogeneous at a nanoscale level, and nanoscale fracture caused by the bubbles that are formed from dissolved hydrogen molecules after decompression occurs even though no cracks are observed by optical microscopy. Since this nanoscale fracture occurred at a threshold tearing energy lower than that obtained from static crack growth tests of macroscopic cracks (T s,th), it is supposed that nanoscale structures that fractured at a lower threshold tearing energy (T nano,th) than T s,th existed in the rubber matrix, and these low-strength structures were the origin of the nanoscale fracture. From these results, it is inferred that the fracture of the EPDM rubber by high-pressure hydrogen decompression consists of two fracture processes that differ in terms of size scale, i.e., bubble formation at a submicrometer level and crack initiation at a micrometer level. The hydrogen pressures at bubble formation and crack initiation were also estimated by assuming two threshold tearing energies, T nano,th for the bubble formation and T s,th for the crack initiation, in terms of fracture mechanics. As a result, the experimental hydrogen pressures were successfully estimated.  相似文献   
7.
Recently, a commercial version of a residential solid oxide fuel cell (SOFC) system with a flat tubular cell has been developed. However, the system cost still remains very high, which is a barrier to its widespread use. In this study, the potential for cost reductions in SOFC stack production was investigated in order to contribute to the viability of the widespread use of such residential SOFC systems in future. A cost analysis of 700 W SOFC stack production based on a process integration modeling was conducted. The present bottom–up approach enabled us to perform a sensitivity analysis with a variety of parameters in terms of cell design, the production process and cell performance. This allowed us to investigate the effects of these factors on the production cost, thereby revealing the quantitative impact of each technological improvement on the cost reduction potential. The present analysis also revealed innovation pathways which could result in technology scenarios where residential SOFC systems could reach a break-even point in comparison with the baseload electricity cost. The analysis of the cost reduction potential presented here provides a useful viewpoint for developing a research strategy for state-of-the-art SOFC technology.  相似文献   
8.
The fatigue limit properties of a carbon steel and a low-alloy CrMo steel were investigated via fully-reversed tension-compression tests, using smooth specimens in air and in 115-MPa hydrogen gas. With respect to the CrMo steel, specimens with sharp notches were also tested in order to investigate the threshold behavior of small cracks. The obtained SN data inferred that the fatigue limit was not negatively affected by hydrogen in either of the steels. Observation of fatigue cracks in the unbroken specimens revealed that non-propagating cracks can exist even in 115-MPa hydrogen gas, and that the crack growth threshold is not degraded by hydrogen. The experimental results provide justification for the fatigue limit design of components that are to be exposed to high-pressure hydrogen gas.  相似文献   
9.
Assessments of global warming mitigation technologies are important for achieving the Kyoto target and planning post‐Kyoto regimes. Regional differences in energy resources, growth in energy consumption, current technology diffusions, etc., should be considered in the assessments. A global energy systems model, DNE21+, with high regional resolution had treated the energy supply sectors in a bottom‐up fashion and the end‐use sectors in a top‐down fashion, which was expressed by using long‐term price elasticity. However, the assessments of technological options in the end‐use sectors are currently more important, particularly for the near and middle terms. In order to evaluate the technological options not only in the energy supply sectors but also in the end‐use sectors for energy savings and CO2 emission reductions, DNE21+ has been modified for treating two energy‐intensive end‐use sectors, i.e. steel and cement sectors, in the bottom‐up fashion. The results reveal that the cost‐effective global CO2 emission reductions in 2030 for stabilizing the atmospheric CO2 concentration at 550 ppmv in comparison with that in the reference case would be approximately 68 MtC/yr and almost zero in the steel and cement sectors, respectively. The cost‐effective options include next‐generation coke ovens and coke dry quenching (CDQ) in the steel sector. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
10.
We have used linear dichroism spectroscopy to measure the dynamic alignment of single-walled carbon nanotubes (SWNT) in pulsed magnetic fields up to 55 T. We make use of the fact that SWNTs absorb light only when the electric-field vector is oriented parallel to the tube axis. SWNTs thus produce a polarization dependent change of the optical transmission, that permits precise measurements of their orientation. In order to distinguish the influence of different mechanisms governing the alignment such as the external magnetic field, Brownian motion or the tube length, we have systematically varied parameters such as the viscosity of the aqueous solution and the sample temperature.  相似文献   
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