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51.
Laboratory accumulation and excretion experiments of 4-nonylphenols (NP) and 4-tert-octylphenol (OP) were performed for killifish (Oryzias latipes). The bioconcentration factors (BCF, wet weight) in the whole fish were mean +/- SD of 167 +/- 23 (n = 4) for NP and 261 +/- 62 (n = 4) for OP. The biological half-lives in the whole fish were 9.9 h for NP and 7.7 h for OP. Parallel to the laboratory experiments, field survey on the chemicals contamination for water and ayu fish (Plecoglossus altivelis) from rivers flowing into Lake Biwa was performed. The contamination was not so high in agreement with the laboratory experimental data and the field BCF values (wet weight) in the ayu fish were 21 +/- 15 (n = 8) for NP and 297 +/- 194 (n = 3) for OP.  相似文献   
52.
Well-conserved three consecutive Pro residues (Pro247–249) in the NADH-binding subdomain of NADH-cytochrome b5 reductase were proposed to form a basal part of the NADH-binding site. To investigate the structural and mechanistic roles of these residues, we expressed site-directed mutants for a soluble domain of the porcine enzyme where each of the residues was replaced with either Ala or Leu residue, respectively, using a heterologous expression system in Escherichia coli. Six mutants (P247A, P247L, P248A, P248L, P249A, and P249L) were produced as a fusion protein containing a 6×His-tag sequence at the NH2-terminus and were purified to homogeneity with a stoichiometric amount of bound FAD. Mutations were each confirmed for the purified proteins by MALDI-TOF mass spectrometry. Steady-state kinetic analyses for NADH:ferricyanide reductase and NADH:cytochrome b5 reductase acitivities were conducted for all the mutants. Substitution of Pro247 with Leu residue was found to significantly decrease kcat with slight increase in Km for the physiological electron donor NADH. However, Km values for the electron acceptors (both cytochrome b5 and ferricyanide) of P247L were found to be decreased significantly. Such changes were not observed for P247A or other four mutants. These results suggested that Pro247 among the three consecutive Pro residues has the most important role for the formation of a binding site cavity and that only a slight change in the side-chain volume at this residue from Ala to Leu residue affected the electron transfer reaction from NADH and, further, on the recognition of ferricytochrome b5.  相似文献   
53.
Crystal-to-crystal transformation from a 3D interpenetrated-type MOF {[Cu(BF(4))(2)(bpy)(H(2)O)(2)] (bpy)} (1) to a 2D square-grid-type [Cu(BF(4))(2)(bpy)(2)] (2) (bpy = 4,4'-bipyridine) was observed. It was derived from dehydration and confirmed by in situ FT-IR, TG, and elemental analysis. Moreover, we elucidate the novel expansion/shrinkage dynamic modulation of 2 triggered by clathrate formation with gas molecules.  相似文献   
54.
In order to make a breakthrough for the acute problem of water shortage in the world, the key words "decentralization and re-use" are very important for new sustainable sanitation systems that will be developed. Therefore, we focused on a new treatments system called "a slanted soil treatment system" which combines a biotoilet system with a domestic grey water treatment system. Because this system is a low cost and compact system, the system can be easily introduced to homes in urban areas or in the suburbs of cities in many developing countries. In this study, we performed on site experiments carried out on Shikoku Island, Japan, for several years. We obtained the following results. The slanted soil treatment system could remove organic pollutants and total nitrogen and total phosphorus in grey water effectively. Furthermore, the system performance became high in the case of the high concentration of the influent water. The nitrification reaction and denitrification reaction were speculated to exist due to aerobic zones and anaerobic zones present in the slanted soil treatment system. The slanted soil treatment system could perform for approximately 3 years with zero maintenance. The plug flow model of 1st order reaction kinetics could describe the reaction in the slanted soil treatment system. However, it is necessary to improve the system to maintain the performance in all seasons.  相似文献   
55.
ABSTRACT

A new compact and wide-band erbium-doped fibre amplifier (EDFA) was demonstrated by combining Hafnia-bismuth Erbium co-doped fibre (HB-EDF) and zirconia–yttria–aluminum Erbium co-doped fibre (Zr-EDF) as a hybrid gain medium, in parallel double-pass configuration. The proposed amplifier comprises a 0.5?m long HB-EDF and 4?m long Zr-EDF optimized for C- and L-band operations, respectively. The HB-EDF and Zr-EDF has erbium ion concentration of 12,500?ppm and 2800?ppm, respectively. At -10 dBm input signal, a wide-band flat gain of 15.7?dB is achieved with gain fluctuation of less than 1.5?dB within a wavelength region from 1525 to 1600?nm. Compared to same configuration of HB-EDF and Zr-EDF amplifiers which are using two pieces of HB-EDF and Zr-EDF, respectively with the same total amount of erbium ions, the proposed EDFA with hybrid gain medium provides even better performances in term of flat gain, bandwidth and noise figure.  相似文献   
56.
An enzymatic micromethod for the determination of acetoin is described. The procedure involves spectrophotometric measurement of the amount of NADH utilised for the reduction of acetoin by 2,3-butanediol dehydrogenase at pH 6.5. The enzyme, partially purified from a strain of Sarcina, is quite stable at — 17 °C. Some other carbonyl compounds, especially acetaldehyde and diacetyl, interfere in the procedure. This interference can be eliminated by the addition of o-phenylenediamine to the sample solution. Acids, sugars and 2,3-butanediol do not interfere. By this method satisfactory results can be obtained in direct determination of acetoin in wines. Some red wines may require a decolorisation treatment before assay, but the treatment has little influence on the determination.  相似文献   
57.
The emergence of immune-based treatments for cancer has led to a growing field dedicated to understanding and managing iatrogenic immunotoxicities that arise from these agents. Immune-related adverse events (irAEs) can develop as isolated events or as toxicities affecting multiple body systems. In particular, this review details the neurological irAEs from immune checkpoint inhibitors (ICI) and chimeric antigen receptor (CAR) T cell immunotherapies. The recognition and treatment of neurological irAEs has variable success, depending on the severity and nature of the neurological involvement. Understanding the involved mechanisms, predicting those at higher risk for irAEs, and establishing safety parameters for resuming cancer immunotherapies after irAEs are all important fields of ongoing research.  相似文献   
58.
The generation of uniform soliton pulse trains by additive pulse mode locking has been experimentally demonstrated in a birefringent fiber laser with a passive polarizer. Numerical simulations of pulse propagation around such a fiber loop are presented which reveal that this mode-locking scheme does not result in strictly uniform pulse trains. Rather, the train of output pulses exhibits periodic fluctuations in intensity and polarization. A model for the pulse dynamics is developed which shows that these fluctuations depend on the strength of the fiber birefringence and the alignment of the polarizer with the fast- and slow-polarization axes of the fiber. It is also shown that increased uniformity of pulse trains is achieved with near alignment of the polarizer with the slow axis of the birefringence  相似文献   
59.
The present study investigated the effects of touch button size on touchscreen operability and compared these effects between young adult and elderly participants. A total of 21 young adults (aged 22.3 ± 1.5 years) and 20 elderly adults (aged 68.1 ±4.9 years) were recruited and asked to press square number buttons (from 0 to 9) on an experimental touchscreen with their right index finger. The buttons' size changed during the experiment with six conditions (6, 8, 10, 12, 14 and 16 mm). It was found that a decrease of the button size to l0 mm or below tended to increase the operation time and error rate, whereas it decreased the subjective overall operability of the touchscreen. Such effects were greater in the elderly adults than in the young adults. In addition, the reaction positions on the buttons were found to be close to the right side of them, which led the fingertip to approach the right outline of the buttons. These findings suggest that the use of small touch buttons should be minimised on touchscreens, especially for elderly users.  相似文献   
60.
Groundwater replenishment by infiltration of road runoff is expected to be a promising option for ensuring a sustainable urban water cycle. In this study, we performed a soil infiltration column test using artificial road runoff equivalent to approximately 11-12 years of rainfall to evaluate the removal of pollutants by using various chemical analyses and bioassay tests. These results indicated that soil infiltration treatment works effectively to remove most of the pollutants such as organic matter (chemical oxygen demand (CODMn) and dissolved organic carbon (DOC)), P species, polycyclic aromatic hydrocarbons (PAHs), numerous heavy metals and oestrogenic activities. Bioassay tests, including algal growth inhibition test, Microtox and mutagen formation potential (MFP) test, also revealed effective removal of toxicities by the soils. However, limited amounts of NO3, Mn, Ni, alkaline earth metals, perfluorooctane sulphonate (PFOS) and perfluorooctane sulphonamide (FOSA) were removed by the soils and they possibly reach the groundwater and cause contamination.  相似文献   
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