Removal Characteristics of Water Treatment Systems Applied to Deconstruction Effluents

汚染源を対象とする浄化対策へ水処理システムを適用する場合, 水質変動への安全率や事業コストを考慮した合理的なシステムが求められる。合理的なシステムを構築するためには, 様々な実践データの蓄積が重要である。本論文では, 焼却施設解体工事の除染工程から発生する排水に対し, 現場において凝集沈殿処理, 膜ろ過処理, 促進酸化処理からなる水処理システムが適用された事例について報告する。当該処理システムにおいて, 重金属類は凝集沈殿処理および膜ろ過処理によって環境基準以下まで除去可能であった。ダイオキシン類については, 微粒子の凝集操作を適切におこなうことにより, 膜ろ過および促進酸化処理による除去性能が向上する傾向が見られ, 環境基準以下まで除去可能であった。合理的な水処理システムを適用するためには, 排水の発生過程と性状, 処理システム全体での除去特性を考慮して検討する必要があることを示した

Surface Roughness Control Based on Digital Copy Milling Concept to Achieve Autonomous Milling Operation

AbstractIn order to develop an autonomous and intelligent machine tool, a system named Digital Copy Milling (DCM) was developed in our previous studies. The DCM generates tool paths in real time based on the principle of copy milling. In the DCM, the cutting tool is controlled dynamically to follow the surface of CAD model corresponding to the machined shape without any NC program. In this study, surface roughness control of finished surface is performed as an enhanced function of DCM. From rough-cut to semi-finish-cut and finish-cut operations, the DCM selects cutting conditions and generates tool paths dynamically to satisfy instructed surface roughness Ra. The experimental verification was performed successfully

Ni@onion-like carbon and Co@amorphous carbon: control of carbon structures by metal ion species in MOFs

We first report the facile synthesis of metal-carbon composites consisting of metal nanoparticles (NPs) and different types of carbon species: onion-like and amorphous carbon, Ni@onion-like carbon and Co@amorphous carbon. By simply changing the metal species in an isostructural metal-organic framework, thermal decompositions of MOF-74 directly afforded different types of metal NPs and carbon composites, which exhibited good electrical conductivity. In particular, the Ni@onion-like carbon, having a well-ordered carbon structure, had high electrical conductivity (sigma = 5.3 omega(-1) cm(-1) at 295 K), explained by a modified model of the Efros-Shklovskii variable range hopping

Frequency-dependent ERK phosphorylation in spinal neurons by electric stimulation of the sciatic nerve and the role in electrophysiological activity

The phosphorylation of extracellular signal-regulated kinase (pERK) in DRG and dorsal horn neurons is induced by the C-fiber electrical stimulation to the peripheral nerve. The present study was designed to investigate the expression and modulation of pERK in the rat dorsal horn neurons produced by repetitive electrical stimulation, and its involvement in the electrophysiological activity of dorsal horn neurons. Electrical stimulation of C-fiber intensity at different frequencies was applied to the sciatic nerve; the stimuli-induced pERK expression and the activity in dorsal horn neurons were studied by immunohistochemistry and extracellular recording, respectively. Electrical stimulation of C-fibers (3 mA) induced pERK expression in dorsal horn neurons in a frequency-dependent manner, indicating that the frequency of electrical stimulation is an important factor which activates the intracellular signal pathway in the spinal cord. To demonstrate the underlying mechanism of this frequency-dependent pERK expression, an NMDA receptor antagonist, MK-801, and a voltage sensitive calcium channel antagonist, nifedipine, were administrated intrathecally before the stimulation. We found that high frequency (0.5 Hz and 10 Hz) but not low frequent (0.05 Hz) stimulus-evoked pERK was partially inhibited by MK-801. Both high and low frequency stimulus-evoked pERK were inhibited by the nifedipine treatment. The extracellular single unit activities were recorded from the laminae I-II and V of the L4-5 dorsal horn, and we found that blockage of the intracellular ERK signal suppressed the wind-up responses in a dose-dependent manner. In contrast, any change in the mechanically evoked responses was not observed following the administration of ERK inhibitor. These observations indicate that ERK activation plays an important role in the induction of the wind-up responses in dorsal horn nociceptive neurons

Distinct Effects of Ketone Bodies on Down-Regulation of Cell Surface Insulin Receptor and Insulin Receptor Substrate-1 Phosphorylation in Adrenal Chromaffin Cells

ABSTRACT Treatment (м24 h) of cultured bovine adrenal chromaffin cells with ketoacidosis-related concentrations (м3 mM) of acetoacetate (but not ␤-hydroxybutyrate, acetone, and acidic medium) caused a time-and concentration-dependent reduction of cell surface 125 I-insulin binding by ϳ38%, with no change in the K d value. The reduction of 125 I-insulin binding returned to control nontreated level at 24 h after the washout of acetoacetate-treated cells. Acetoacetate did not increase the internalization rate of cell surface insulin receptor (IR), as measured in the presence of brefeldin A, an inhibitor of cell surface vesicular exit from the trans-Golgi network. Acetoacetate (10 mM for 24 h) lowered cellular levels of the immunoreactive IR precursor molecule (ϳ190 kDa) and IR by 22 and 28%, respectively. Acetoacetate decreased IR mRNA levels by ϳ23% as early as 6 h, producing their maximum plateau reduction at 12 and 24 h. The half-life of IR mRNA was shortened by acetoacetate from 13.6 to 9.5 h. Immunoprecipitation followed by immunoblot analysis revealed that insulin-induced (100 nM for 10 min) tyrosine-phosphorylation of insulin receptor substrate-1 (IRS-1) was attenuated by 56% in acetoacetate-treated cells, with no change in IRS-1 level. These results suggest that chronic treatment with acetoacetate selectively down-regulated the density of cell surface functional IR via lowering IR mRNA levels and IR synthesis, thereby retarding insulin-induced activation of IRS-1

Genome-Scale CRISPR/Cas9 Screening Reveals Squalene Epoxidase as a Susceptibility Factor for Cytotoxicity of Malformin A1

Malformin A1 (MA1) is a fungus-produced cyclic pentapeptide. MA1 exhibits teratogenicity to plants, fibrinolysis-enhancing activity, and cytotoxicity to mammalian cells. To clarify the cytotoxic mechanism of MA1, we screened for the genes involved in the cytotoxicity of MA1 in monocytoid U937 cells by using a CRISPR/Cas9-based genome-wide knockout library. Screening was performed by positive selection for cells that were resistant to MA1 treatment, and single guide RNAs (sgRNAs) integrated into MA1-resistant cells were analyzed by high-throughput sequencing. As a result of the evaluation of sgRNAs that were enriched in MA1-resistant cells, SQLE, which encodes squalene epoxidase, was identified as a candidate gene. SQLE-depleted U937 cells were viable in the presence of MA1, and squalene epoxidase inhibitor conferred MA1 resistance to wild-type cells. These results indicate that squalene epoxidase is implicated in the cytotoxicity of MA1. This finding represents a new insight into applications of MA1 for treating ischemic diseases

Efficient overall water splitting in acid with anisotropic metal nanosheets

超高効率な水の電気分解を実現するナノシート状合金触媒を開発 --再生可能エネルギーによる水素社会実現へ大きく貢献--. 京都大学プレスリリース. 2021-02-17.Water is the only available fossil-free source of hydrogen. Splitting water electrochemically is among the most used techniques, however, it accounts for only 4% of global hydrogen production. One of the reasons is the high cost and low performance of catalysts promoting the oxygen evolution reaction (OER). Here, we report a highly efficient catalyst in acid, that is, solid-solution Ru‒Ir nanosized-coral (RuIr-NC) consisting of 3 nm-thick sheets with only 6 at.% Ir. Among OER catalysts, RuIr-NC shows the highest intrinsic activity and stability. A home-made overall water splitting cell using RuIr-NC as both electrodes can reach 10 mA cm−2geo at 1.485 V for 120 h without noticeable degradation, which outperforms known cells. Operando spectroscopy and atomic-resolution electron microscopy indicate that the high-performance results from the ability of the preferentially exposed {0001} facets to resist the formation of dissolvable metal oxides and to transform ephemeral Ru into a long-lived catalyst