Effects of sea surface temperature accuracy on offshore wind resource assessment using a mesoscale model

Offshore wind simulations were performed with the Weather Research and Forecasting (WRF) model driven by three different sea surface temperature (SST) datasets for Japanese coastal waters to investigate the effect of the SST accuracies on offshore wind simulations. First, the National Centers for Environmental Prediction Final analysis (FNL) (1° × 1° grid resolution) and the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) (0.05° × 0.05° grid resolution) datasets were compared with in situ measurements. The results show a decrease in accuracy of these datasets toward the coast from the open ocean. Aiming at an improved accuracy of SST data, we developed a new high‐resolution SST dataset (0.02° × 0.02° grid resolution). The new dataset referred to as MOSST is based on the Moderate Resolution Imaging Spectroradiometer (MODIS) product, provided by the Japan Aerospace Exploration Agency (JAXA). MOSST was confirmed to be more accurate than FNL and OSTIA for the coastal waters. Then, WRF simulations were carried out for 1 year with a 2 km grid resolution and by using the FNL, OSTIA and MOSST datasets. The use of the OSTIA dataset for a WRF simulation was found to improve the accuracy when compared with the FNL dataset, and further improvement was obtained when the MOSST dataset was applied. The sensitivity of wind speed and wind energy density to SST is also discussed. We conclude that the use of an accurate SST is a key factor not only for realistic offshore wind simulations near the surface but also for accurate wind resource assessments at the hub height of wind turbines. Copyright © 2014 John Wiley & Sons, Ltd.     

Dispersion in the Presence of Acetic Acid or Ammonia Confers Gliadin‐Like Characteristics to the Glutenin in Wheat Gluten

Spray‐dried gluten has unique properties and is commercially available in the food industry worldwide. In this study, we examined the viscoelastic properties of gluten powder prepared by dispersion in the presence of acetic acid or an ammonia solvent and then followed by lyophilization instead of a spray drying. Mixograph measurements showed that the acid‐ and ammonia‐treated gluten powders had marked decreases in the time to peak dough resistance when compared with the control gluten powder. The integrals of the dough resistance and bandwidth for 3 min after peak dough resistance decreased in both treated gluten powders. Similar phenomena were observed when gliadin was supplemented to gluten powders. Basic and acidic conditions were applied to the acid‐ and ammonia‐treated gluten powders, respectively, and the viscoelastic behaviors were found to depend on the pH in the gluten dispersion just before lyophilization. These behaviors suggest that gluten may assume a reversible change in viscoelasticity by a fluctuation in pH during gluten dispersion. SDS‐PAGE showed that the extractable proteins substantially increased in some polymeric glutenins including the low molecular weight‐glutenin subunit (LMW‐GS) when the ammonia‐treated gluten powder was extracted with 70% ethanol. In contrast, the extractable proteins markedly increased in many polymeric glutenins including the high molecular weight‐glutenin subunit and/or the LMW‐GS when the acid‐treated gluten powder was extracted with 70% ethanol. It thus follows that the extractability of polymeric glutenin to ethanol increases similarly to gliadin when gluten is exposed to an acidic or a basic pH condition; therefore, glutenin adopts gliadin‐like characteristics.     

Connected word recognition using a cascaded neuro-computational model

We propose a novel framework for processing a continuous speech stream that contains a varying number of words, as well as non-speech periods. Speech samples are segmented into word-tokens and non-speech periods. An augmented version of an earlier-proposed, cascaded neuro-computational model is used for recognising individual words within the stream. Simulation studies using both a multi-speaker-dependent and speaker-independent digit string database show that the proposed method yields a recognition performance comparable to that obtained by a benchmark approach using hidden Markov models with embedded training.     

Development of confocal laser microscope system for examination of microscopic characteristics of radiophotoluminescence glass dosemeters

A confocal laser microscope system was developed for the measurement of radiophotoluminescence (RPL) photons emitted from a minute alpha-ray-irradiated area in an RPL glass dosemeter. The system was composed mainly of an inverted-type microscope, an ultraviolet laser, an XY movable stage and photon-counting circuits. The photon-counting circuits were effective in the reduction of the background noise level in the measurement of RPL photons. The performance of this microscope system was examined by the observation of standard RPL glass samples irradiated using (241)Am alpha rays. The spatial resolution of this system was ～ 3 μm, and with regard to the sensitivity of this system, a hit of more than four to five alpha rays in unit area produced enough amount of RPL photons to construct the image.     

Evaluation of the historical records of lead pollution in the annual growth rings and bark pockets of a 250-year-old Quercus crispula in Nikko,Japan

The annual growth rings and bark pockets of a 250-year-old Japanese oak (Quercus crispula), collected from the Nikko National Park, Japan in 2000 AD, were analysed by ICP mass spectrometry. The annual rings, sampled in 5-year increments, recorded Pb concentrations from 0.01 to 0.1 mg kg(-1) and there was no significant change in concentration with time. In contrast, bark pocket samples dating from 1875 to the present showed a progressive increase in Pb concentration with time, from approximately 0.1 to 10 mg kg(-1). Shoots of epiphytic moss growing on the tree trunk contained 17 mg kg(-1) Pb. The bark pockets recorded historical increases in airborne Pb pollution accompanying the industrialisation of Japan, which was initiated by the opening of Japan's borders from 1854. This increase was not reflected by the annual rings. The 206Pb/207Pb isotope ratio of the bark pockets decreased from approximately 1.18 to 1.16 from 1964 to the present, indicating changes in the sources of Pb pollution. The 206Pb/207Pb isotope ratio of the moss shoots was similar to the current bark (1.16). The data showed bark pockets to be more effective than annual rings for recording historical change in airborne lead pollution.     

Detection of norovirus RNA in bivalve molluscs by using bacteria-culture-employed method (A3T method)

Norovirus (NV) RNA has rarely been detected in foods despite the use of highly sensitive methods such as RT-PCR and real-time RT-PCR. In the modified method (A3T method) reported previously, a bacterial culture process was introduced into the standard protocol for NV detection to remove some inhibitor(s) present in food ingredients. To confirm the efficiency of the A3T method and to examine NV contamination in bivalve molluscs, we tried to detect NV RNA in bivalve molluscs on the market and in oyster samples associated with foodborne outbreaks by using the standard method and the A3T method. NV RNAs were detected in 20 samples (18.0%) of 111 bivalve molluscs, including oysters, on the market by use of the A3T method, while only one sample (0.9%) was positive according to the standard method. NV RNA was also detected in 10 of 35 oyster samples related to foodborne outbreaks by the A3T method. Those results show that the A3T method is suitable for the detection of NV in bivalve molluscs in general laboratories.     

Alteration of substrate specificity of rat neurolysin from matrix metalloproteinase-2/9-type to -3-type specificity by comprehensive mutation

The substrate specificity of rat brain neurolysin was rapidly modified by semirational mutagenesis coupled with a yeast molecular display system. Neurolysin mainly recognizes substrates with sequential six residues close to the scissile bond in polypeptides, cleaving a peptide bond in the center position of the six residues. To alter the recognition of the P2' amino acid of substrates by neurolysin, six residues of neurolysin, Asp467, Arg470, Glu510, Tyr606, Tyr610 and Tyr611, which might be involved in the formation of the neurolysin S2' subsite, were individually and comprehensively substituted. The protein libraries of mutant neurolysins comprising 120 species were displayed on the yeast cell surface and screening was carried out using two fluorescence-quenching peptides, the matrix metalloproteinase-2/9- (MMPs-2/9-) and MMP-3-specific substrates, which consisted of similar amino acids, except for alanine (for MMPs-2/9) or glutamic acid (for MMP-3) at the P2' amino acid position. Among mutant neurolysins, the Y610L mutant neurolysin exhibited a marked change in substrate specificity. Steady-state kinetic analysis of the purified Y610L mutant neurolysin revealed that the binding efficiency toward the MMP-3-specific substrate was about 3-fold higher than that toward the MMP-2/9-specific substrate. These results indicate that Tyr610 of neurolysin is the important residue to recognize the P2' amino acid of substrates.     

Gelation of poly(vinyl alcohol) solutions at low temperatures (20 to −78°C) and properties of gels

The flow points of atactic poly(vinyl alcohol) (a-PVA) gels with H₂O/dimethyl sulfoxide (DMSO) = 90/10 (v/v) chilled at 20 to ?78°C for 24 h depended on the chilling temperature and were 0–30°C for gels with the initial polymer concentrations (C_i) of 2–5 g/dL, whereas those for H₂O/DMSO = 50/50 chilled at 0 to ?78°C were independent of the chilling temperature and were 70–75°C. Syneresis occurred after eight cycles of freezing (?24°C) and thawing (20°C) for a-PVA hydrogels at concentrations above C_i = 4 g/dL and two such cycles for syndiotacticity-rich PVA (s-PVA) hydrogels at concentrations above C_i = 1 g/dL. The extent of syneresis per one cycle for s-PVA hydrogels was higher than that for a-PVA hydrogels at the initial cycles. In the a-PVA hydrogels with an initial polymer concentration of ca. 30 g/dL, syneresis was expected not to occur even after 20 cycles. If all the free water in the gels is assumed to have transuded by syneresis after 20 cycles, the residual water is bound water and is estimated to be six water molecules per one vinyl alcohol monomer unit. © 1994 John Wiley & Sons, Inc.     

A comparison of lead isotope ratios in the bark pockets and annual rings of two beech trees collected in Derbyshire and South Yorkshire, UK

ICP-MS analysis of the bark pockets and annual rings of two beech (Fagus sylvatica L.) trees collected from Longshaw, Derbyshire and Swinton, South Yorkshire in the UK recorded differences in the (206)Pb/(207)Pb isotope ratio. In the Longshaw sample, the (206)Pb/(207)Pb isotope ratio of the bark pockets ( approximately 1914-1998, 78-260 microg g(-1) Pb) declined from approximately 1.16 to 1.12, whilst the annual rings (1899-1998, 0.2-2.5 microg g(-1) Pb) had a (206)Pb/(207)Pb ratio of approximately 1.18. In the Swinton sample, the bark pockets (approximately 1919-1998, 7-78 microg g(-1) Pb) declined from 1.15 to 1.11 and the annual rings (1899-1998, 0.2-0.5 microg g(-1) Pb) from 1.18 to 1.15. The data implied that the bark pockets accumulated lead directly from the atmosphere through wet and dry deposition, whilst the annual rings accumulated lead from the soil via the roots. The bark pockets recorded a relative decline in the accumulation of lead from indigenous sources, such as lead smelting and coal combustion (1.17-1.19), and increase in imported sources such as the smelting of Australian ores (1.04) and leaded petrol usage (1.06-1.09). In contrast, the annual rings at Longshaw recorded ratios typical of indigenous lead, whilst the annual rings in Swinton recorded a relatively small decrease in (206)Pb/(207)Pb reflecting leaded petrol usage. The decline in (206)Pb/(207)Pb of the bark pockets was consistent with the historical decline in (206)Pb/(207)Pb of atmospheric lead recorded in peat, lake sediments and archival herbage at other UK locations.