Effects of setting up of humidifiers on thermal conditions and subjective responses of patients and staff in a hospital during winter

The purpose of this survey was to measure the thermal environment in a hospital during winter, and to investigate the subjective responses of patients and staff via a questionnaire. The air temperature and humidity in the sickrooms and nurse stations were measured for 3 months during winter. After 2 months, we introduced humidifiers into about half of the rooms and nurse stations as a method of improving the environment, and evaluated the effects of the installed humidifiers on the thermal conditions. In all, 36 patients and 45 staff members were asked once a week about subjective symptoms (dry and itchy skin, thirst, etc.). Before setting up the humidifiers, the existence of a low-humidity environment in the hospital during winter was confirmed, with the levels of relative humidity and humidity ratio reaching under 50% and 5g/kg DA, respectively, which is known to promote the spread of influenza viruses. However, the introduction of the humidifiers increased the relative humidity in sickrooms from 32.8% to 43.9% on average, and the air humidity in sickrooms thus almost reached the optimum range suggested by the Hospital Engineering Association of Japan (HEAJ). Additionally, complaints of thermal discomfort and dryness of air decreased among the staff, though not among the patients, after the humidifiers were installed. These results suggest that introducing humidifiers into a hospital during winter is an effective method of improving the low-humidity environment and relieving the discomfort of staff members.     

Finite spectrum assignment of multi-input systems with non-commensurate delays

We present a new framework for finite spectrum assignment for multi-input systems with non-commensurate delays using an algebraic approach over multidimensional polynomial matrices. By focusing on the solvability of a Bezout equation over multidimensional polynomial matrices, we derive a necessary and sufficient condition for finite spectrum assignability under which a finite number of spectra can be assigned by a control law using a ring of entire functions, i.e. Laplace transforms of all exponential time functions with compact support. Furthermore, using a solution to the Bezout equation, we present a design method for a controller that achieves finite spectrum assignment.     

Thermal stability of chimeric isopropylmalate dehydrogenase genes constructed from a thermophile and a mesophile

Chimeric isopropylmalate dehydrogenases were constructed byconnecting the genes isolated from an extreme thermophile, Thermusthermophilus, and a mesophile, Bacillus subtilis. These geneswere expressed in Escherichia coli. The enzymes were purifiedand analysed. Enzymes of T.thermophilus and B.subtilis and chimericenzymes showed similar enzymological characteristics exceptfor thermal stability. The stability of each enzyme was approximatelyproportional to the content of the amino acid sequence fromthe TJhermophilus enzyme. The results suggested that amino acidresidues contributing the thermal stability distribute themselves,in general, evenly at least in the N-terminal half of the aminoacid sequence of T.thermophilus isopropylmalate dehydrogenase.     

Strategic trade policy under isoelastic demand and asymmetric production costs

We demonstrate that whether a good of a rival firm is a strategic substitute or a strategic complement is endogenously determined when the market inverse demand is hyperbolic. The relative competitiveness, which is expressed by the ratio of firms’ marginal costs, is the key factor. We derive optimal trade policies, which are dependent upon the firms’ form of strategic action. In particular, it is shown that if the home firm is relatively more efficient (inefficient) than the foreign rival, then it regards the rival’s choice variable as a strategic complement (substitute) and thus the optimal policy recommendation for the home government is to impose an export tax (to give an export subsidy) to the home firm.     

Computer supported environment for common exploitation of personal information

Personal connections have great influences on various social activities, e.g., a business negotiation. However, data of personal connections are usually diverse, dynamic and ill-formed. In this paper, we firstly propose a model and representation for personal connections, then describe the framework to deal with ill-formed information. We discuss some key criteria on developing a common exploitation environment integrated with an adaptable data-base and user interface to support group decision. Finally, we give illustrations to show that the developed environment is effective and useful.     

Purification and characterization of intracellular and extracellular, thermostable and alkali-tolerant alcohol oxidases produced by a thermophilic fungus, Thermoascus aurantiacus NBRC 31693

Intracellular and extracellular alcohol oxidases (AO int and AO ext) were purified from the liquid and solid cultures of a thermophilic fungus, Thermoascus aurantiacus NBRC 31693, as electrophoretically and isoelectrophoretically homogeneous proteins, respectively. Both enzymes contained a flavin adenine dinucleotide (FAD) cofactor and were stained with Schiff's reagent. The molecular weight of AO int was estimated to be about 320 kDa and its subunit was 75 kDa. The molecular weight of AO ext was about 560 kDa, and it was composed of two types of subunits (75 kDa and 59 kDa). The pIs of AO int and AO ext were 5.88 and 6.08, respectively. AO int and AO ext were stable up to 60 degrees C and 55 degrees C, respectively. The enzymes were stable over a wide range of pH from 6 to 11. AO int oxidized short straight-chain alcohols (K(m) for methanol, 13.5 mM and K(m) for ethanol, 15.8 mM). On the other hand, AO ext could oxidize secondary alcohols and aromatic alcohols (veratryl alcohol and benzyl alcohol) in addition to straight-chain alcohols (K(m) for methanol, 0.5 mM and K(m) for ethanol, 10.2 mM).     

SEM and TEM characterization of magnesium hydride catalyzed with Ni nano-particle or Nb2O5

The microstructures of MgH₂ catalyzed with Ni nano-particle or Nb₂O₅ mesoporous powders are examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations. For MgH₂ catalyzed with Ni, the Ni particles with the diameter smaller than 1 μm were detected on the MgH₂ particles with the diameter smaller than 5 μm by the back scattering electron (BSE) microscopy. In details, the TEM micrograph indicates that the Ni particles distribute 20 nm in diameter on MgH₂ uniformly, which was the same size as the additive doped in MgH₂ before milling. On the other hand, for MgH₂ catalyzed with Nb₂O₅, the additive particles could not be found anywhere in the BSE image. Even in the TEM micrograph by much larger magnification than the SEM micrograph, the particles corresponding to the additive cannot be observed at all. Furthermore, an energy dispersive X-ray (EDX) analysis in spots with a diameter of 20 nm indicated that the existing ratio of Mg to Nb was evaluated to 98:2, being the same as the starting ratio before milling. Therefore, the metal oxide Nb₂O₅ becomes extremely small particle that could not be observed by the present work after milling compared to metal Ni^nano.     

On the electric double-layer structure at carbon electrode/organic electrolyte solution interface analyzed by ac impedance and electrochemical quartz-crystal microbalance responses

ac impedance and electrochemical quartz crystal microbalance (EQCM) techniques have been applied to analyze the structure of electric double-layer formed at carbon/organic electrolyte solution interface using a sputtered carbon electrode. The mass changes caused by electrochemical adsorption (accumulation) of ions have been estimated in the solutions of propylene carbonate (PC) dissolving tetrafluoroborate (BF₄⁻) salts of lithium (Li⁺), tetraethylammonium (TEA⁺) and tetra-n-butylammonium (TBA⁺) cations. The observed mass changes during the cathodic polarization in the solutions containing TEA⁺ and TBA⁺ were well consistent with those expected by the calculation based on mono-layer adsorption of the cations with giving the consideration to the surface roughness. On the other hand, the mass change observed in the solution containing Li⁺ salt showed that the solvation of Li⁺ with three or four molecules of PC would be the charge compensation species at the interface. Comparison of the quantity of the electricity passed during the EQCM measurements with that from theoretical calculation with simple Helmholtz-layer model revealed that the major part of the double-layer capacitance would be based on the electrostatic polarization of the solvent molecule directly adsorbed at the carbon surface.     

Monitoring of beef aging using a two-line flow injection analysis biosensor consisting of putrescine and xanthine electrodes

A two-line flow injection analysis (FIA) biosensor was developed which can simultaneously detect bacterial spoilage and the progress of aging. This FIA biosensor was composed of a putrescine oxidase immobilized electrode and a xanthine oxidase immobilized electrode as detectors. The putrescine electrode measures putrescine and cadaverine which are produced by bacteria, and the xanthine electrode measures hypoxanthine and xanthine which accumulate in meat with aging.

The analytical conditions for this system were set as follows; flow rate, 1 ml/ min; water bath temperature, 30 °C; flow buffer, 0.1 M phosphate buffer (pH 7.0); injection volume for putrescine electrode, 200 μl; injection volume for xanthine electrode, 40 μl; and measurement cycle, 2 min.

The linear relationship for standard solution was between 20 and 800 nmol/ml in the putrescine electrode and between 0.1 and 3.0 μmol/ml in the xanthine electrode. The coefficients of variation in standard solutions were 2.14% with the putrescine electrode and 2.83% with the xanthine electrode. The coefficients of variation values in the specimen solution were 3.22% and 3.76%, respectively.

This two-line FIA biosensor was applied to the vacuum-packed beef stored at 0, 5 and 10 °C. The progress of aging could be monitored at all temperatures, and the bacterial spoilage could be detected before the appearance of putrid odor at 5 and 10 °C. However, at 0 °C the putrid odor did not appear during storage, and neither putrescine nor cadaverine was detected. Thus, this FIA biosensor was confirmed to be useful for the quality control of beef aging at 5 and 10 °C, but not at 0 °C.     

Liquid-Phase Sintering of Aluminum Nitride by Europium Oxide Additives

Europium oxide has been investigated as a sintering aid and dopant for AIN. Pressureless sintering was carried out with 0 to 9 wt% Eu₂O₃ additives, and dense sintered specimens were obtained using 1 to 4 wt% Eu₂O₃. With increasing Eu₂O₃ content, two additional phases were observed in the X-ray diffraction patterns. The lattice parameters a and c of AIN in the wurtzite structure changed slightly and non-monotonically with Eu₂O₃ content and showed their minimum value in a 4 wt% Eu₂O₃ sample. The Raman and photoluminescence spectra of sintered specimens were measured. These experimental results and the sintering mechanism in the system were discussed from the standpoint of the effects of oxygen, europium, and stress.