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Magnetic orientational linear dichroism (MOLD) spectra of magnetic nanoparticles (MNPs) in the UV-Vis wavelength region were found to be useful as a probe to detect changes of the dispersion state due to a restriction of the rotational Brownian motion of MNPs; a change of the medium from liquid to resin and the formation of agglomerates in solution. The magnetic-field dependence of MOLD was analyzed by using the Langevin equation, which gave information about the magnetic moment of MNPs.

The electromagnetophoretic behavior of organic droplets in an electrolyte solution was investigated in a silica capillary cell using a superconducting bulk magnet (3.5 T) and a magnetic circuit (2.7 T). The initially dispersed emulsion droplets of dodecane migrated to the wall of the capillary, responding to the direction of an electric current, and coalesced to form smaller and larger droplets after some repeated migrations. When the electric current was applied continuously, the larger droplets became arranged with regular intervals on the wall, and smaller droplets rotated around the larger droplets. These interesting behaviors were analyzed while taking into account the local electric current density determined by the flow velocity of the ionic current around a droplet, which was lowest on the electrode sides of the droplet. The difference in the local electric current density generated the Lorentz-force difference in the medium, which lead to local micro-convection around the droplet, and also the alignment of larger droplets by a repelling effect between the adjacent micro-convections.

The role of an external force on chemical equilibria is an important subject in mechanobiochemistry. The effect of an electromagnetophoretic force for the stretching of cysteamine molecules was examined by using SERS spectrometry. Polystyrene particles modified with cysteamine were bound to silver nanoparticles adsorbed on the wall of a silica capillary cell. Under a constant magnetic field, when an electric current was applied to the conductive medium in the capillary, the shift of SERS bands and the increase of the trans/gauche ratio of cysteamine were observed, suggesting a molecular conformation change of cysteamine due to the stretching force.

A square optical loop used to observe the Sagnac effect was constructed by using a 632.8-nm He-Ne laser, a polarizing beam splitter and three mirrors, combined with a detection system. When a magnetic field was applied from the transversal direction to the beam of the loop, which passed through the sample cell containing magnetic nanoparticles (MNPs) in water, Sagnac interference was observed depending on the concentration of MNPs, indicating evolution of the magnetic birefringence. A possible analytical use of the magnetic Sagnac effect has been suggested.

A simple zero-velocity method to determine the particle magnetic susceptibility by measuring the magnetophoretic velocity was proposed. The principle is that the magnetophoretic velocity of a particle in a liquid medium must be zero when the magnetic susceptibilities of the medium and the particle are equal, or the gravity force and the magnetophoretic force are balanced. By changing the medium magnetic susceptibility and measuring the magnetophoretic velocity of a particle, the particle magnetic susceptibility was determined from the medium magnetic susceptibility under the zero-velocity condition. The feasibility of the method was demonstrated for polystyrene particles using a Dy(III) solution in the horizontal migration mode and different organic solvents in the vertical migration mode.

We constructed an apparatus to measure the wavelength dispersion of the Faraday rotation in the visible region, and determined the Verdet constants of diamagnetic organic liquids, including aliphatic compounds, benzene derivatives, and naphthalene derivatives. These three groups were easily distinguished by the magnitudes of their Verdet constants. Based on the theory developed by Serber, we determined the enhancing effect of π*←π transitions on the visible-light Faraday rotation angles observed for aromatic compounds. Furthermore, we propose a novel approach for simultaneously observing Faraday rotation dispersion and natural optical rotatory dispersion.

The magnetic-force quartz crystal microbalance (QCM) method was attempted for the dynamic evaluation of chemical interactions. Thiol-modified magnetic particles bound to a QCM gold electrode of less than three layers were pulled by a magnetic force, and the dissociation dynamics of the magnetic particles was measured based on the change in the weight as a function of time under different temperatures. From an analysis of the dissociated layers and the activation energy for the dissociation, the chemical interactions between particles were evaluated.

As a tool to determine the magnetic susceptibility of a nano/microparticle in a liquid, a nano-gap magnetophoresis device was fabricated using tilted flat glass plates and a permanent magnet. The nano-gap device was not only used to determine the size of particles, but also directly provided measurements of Raman spectra of fractionally trapped particles in the nano-gap device. The performance of the new hyphenated method was demonstrated by an analysis of suspended particle matter in traffic air.

The effects of stretching forces on covalently bridged 3-mercaptopropanoic acid molecules between magnetic particles (MPs) and Ag nano-particles (NPs) were studied by surface-enhanced Raman scattering (SERS) spectroscopy. With an exertion of 100 pN per single MP, the intensity ratio of the C-S stretching vibrations for trans-to-gauche conformations was increased from 0.295 +/- 0.008 to 0.69 +/- 0.09. From the experimental result, it was concluded that the magnetic forces increased the distance between the MP and the Ag NP surface, and induced a shift of the isomerization equilibrium to the trans conformation. The present approach is a new candidate for a dynamic force spectroscopy of conformational equilibria.

A simple and precise size measurement device of microparticles in liquid has been developed by using a narrow gap between a cylindrical lens and a flat glass wall, in which the distance of the gap is precisely determined by the diffraction Moiré pattern of irradiated light. Two different methods to transfer the particles toward the center line of the lens, a hydrodynamic flow mode and an electrophoretic mode, have been established. By using these methods, simultaneous size-determination and size-separation of small amounts of micrometer and sub-micrometer sized polystyrene particles in water have been attained with high precision. Novel advantages of the cylindrical nano-gap method were demonstrated for different surface types of polystyrene particles.

Background: Laparoscopic gastrectomy is reported to cause little pain. However, only the total number of analgesics used has been studied to date. Because pain is a subjective experience, its evaluation requires indicators for the subjective assessment., Methods: Pain was evaluation for patients after open distal gastrectomy (ODG, 52 cases), laparoscopically assisted distal gastrectomy (LADG, 112 cases), open total gastrectomy (OTG, 18 cases), and laparoscopically assisted total gastrectomy (LATG, 33 cases). The patients were administered continuous epidural anesthesia for 2 days after the surgery. The Wong-Baker FACES pain rating scale was used to evaluate the differences in pain. Each patient was evaluated from postoperative day (POD) 1 to POD 7, and temporal changes in pain were studied comparatively between ODG and LADG and between OTG and LATG., Results: Peak pain scores were recorded on POD 3 for both distal and total gastrectomy. The scores decreased over time after POD 3. There was no significant difference in scores between open and laparoscopic gastrectomy up to POD 2, but lower scores were shown on PODs 3, 4, and 5 for LADG and on days 3 and 4 for LATG., Conclusions: The pain score for laparoscopic gastrectomy was low. There was no significant difference in pain between procedures while epidural anesthesia was in effect. Pain subsided earlier with laparoscopic than with open gastrectomy. The same characteristics were observed with both LADG and LATG.

The purpose of the study reported here was to discuss the level of intelligibility of three-dimensional computed tomography (3D-CT) images of clinical patients for persons who are lacking veterinary knowledge. 143 undergraduate students were participated in this study. They were entirely unfamiliar with veterinary anatomy. A survey was conducted using the visual analog scale method with a focus on the level of intelligibility of the 3D-CT images compared to that of the two-dimensional CT images or radiographs. As a result, the mean value of the intelligibility of the 3D-CT image was 88.4 +/- 17.8 points out of 100 points. In clinical cases, it is very difficult for pet owners lacking veterinary knowledge to understand the clinical status of their pets even with explanations using illustrations, radiographs, and transverse CT images. It is considered that better informed consent and patient satisfaction will be obtained provided veterinarians make an effort towards intelligible patient education by using 3D-CT images.

A microscopic measurement system of circular dichroic spectra of second harmonic generation, which is applicable to detect the chirality of micro-region of molecular aggregates, has been investigated. The performance of the system was demonstrated by the discrimination of chirality of molecular aggregates of porphyrin on a glass plate.

The Faraday rotation of diamagnetic liquids has been measured by applying a pulsed magnetic field. The observed results for water, alcohol, and aliphatic and aromatic organic liquids suggested a possible discrimination of such liquids by Faraday imaging. Actually, we have succeeded to observe Faraday images using a magneto-optical microscope system. The discrimination of several diamagnetic liquids including chiral liquids has been demonstrated.

A microscope device to measure the circular dichroism (CD) spectra of a specified microscopic region of chiral samples was constructed by combining of a couple of objective lenses and a CCD camera, which was installed in a sample chamber of a commercially available CD spectropolarimeter. By using this apparatus, high quality micro-CD spectra in the 60 x 60 microm region of samples could be measured. Micro-CD spectra of thin film of chiral DNA samples on glass and a natural kidney bean leaf were measured, and the potential of the micro-CD apparatus was successfully demonstrated.

Magnetophoretic velocimetry is a novel technique to measure the magnetic susceptibility of a single microparticle. This technique could be applied to study the interfacial adsorption equilibria of a paramagnetic dysprosium(III) ion with capric, lauric or stearic acid for a single 2-fluorotoluene microdroplet. The observed magnetic susceptibility of the micro-organic droplets was reciprocally proportional to its radius in each case. From the proportional constant, the interfacial concentration of Dy(III) was determined. Furthermore, the dependences of the interfacial concentration on the initial Dy(III) concentration and pH were examined in order to analyze the adsorption equilibrium. Finally, the saturated interfacial concentration and the interfacial adsorption constant at the infinite dilution of Dy(III)-laurate complex were evaluated as 4.8 x 10(-10) mol cm(-2) and 3.4 x 10(-2) dm, respectively.

Resonance Raman spectroscopy assisted by centrifugal liquid membrane/circular dichroism (CLM-CD) and UV/Vis absorption spectroscopies was applied to measure the binding state of bilirubin (BR) in the complex with bovine serum albumin (BSA) formed at a heptane/water interface. The bisignate Cotton effects in the interfacial CD spectra and the red shift and linewidth increase of the BR absorption band around 450 nm indicated the formation of the BR-BSA complex at the interface and the chiral conversion of BR molecules in the aggregates. The resonance Raman spectra of BR observed at the interface suggested that the interfacial BR-BSA complex formed during the initial 15 min after the contact of the two phases had a similar structure with that in solution, but after 15 min were forming aggregates coexisting with solid micro-particles. These experimental results strongly suggested that the chiral interconversion of BR from (P+) conformation to (M-) conformation in the interfacial complex was accompanied by aggregation of the BR-BSA complexes. In the present study, resonance Raman microscopic spectrometry was proved to be highly useful for characterizing the solid like aggregate formed at the liquid/liquid interface.

The effects of a magnetic force on magnetic particles linked by cysteamine to a silver colloid plate were analyzed with surface-enhanced Raman scattering spectroscopy. Cysteamine molecules were stretched by a force exerted on the magnetic particles with the external magnetic field gradients generated by two Nd-Fe-B magnets. The spectra showed that the relative intensity ratio of C-S (trans) to C-S (gauche) of cysteamine was increased 2 - 3 times within 30 min under the application of magnetic field gradients. Also, the shift of C-S (T) was observed up to 4 cm(-1) to higher frequency. These results suggested that an extension of the distance between a magnetic particle and a silver colloid induced isomerization from the gauche conformation to the trans conformation, accompanied by probable thiolate migration on the silver colloid surface.

A novel measurement method of the binding force between a micrometer-sized particle and a solid surface in an electrolyte solution has been established by using the electromagnetophoretic buoyancy on the particle. By this method, we investigated the binding force between a yeast cell surface and an oligosaccharide-binding protein, concanavalin A (Con A), fixed on a silica capillary wall. The force measurement was carried out up to 60 pN. In a lower surface concentration of Con A, yeast cells could be desorbed by a force less than 60 pN. However, in a higher surface concentration after treated by 1 mg ml(-1) solution, yeast cells were adsorbed with a force stronger than 60 pN. In this case, the addition of 10 mg ml(-1) D-mannose solution to the medium reduced the binding force to less than 60 pN. The observed adsorption force of yeast cells ranged within 30 - 40 pN, regardless of the interfacial amount of Con A. This force was thought to be the single binding force between a mannose group of the cell surface and an active site of Con A. Moreover, the dissociation rate constant of the single binding of yeast cell and Con A complex was determined as 4.6 x 10(-3) s(-1) and the increment of the binding distance at the transition state as 0.33 nm from the desorption kinetic experiments of yeast cell under the constant pulling conditions of 10, 20 and 30 pN. Such satisfactory results demonstrate the novel advantages of the present method.

A new principle to measure the magnetic susceptibility of a solution was proposed; it utilized the displacement of solution surface caused by the magnetic force applied to the solution. The interfacial displacement was measured with the sensitivity of 5 nm from a change of the interference fringes, so called Newton Ring, generated from the solution surface and an upper surface of a small plano-convex lens on the bottom wall of a cell. The surface displacement measurement was carried out in a homemade cell attached by one or two small Nd-Fe-B magnets. The performance of this method was investigated by the measurements of magnetic susceptibility of manganese(II) chloride solution and some lanthanide(III) solutions. An excellent linear relationship between the magnetic susceptibility and the interfacial displacement was observed for each solution system. Then, it was demonstrated that this relationship could be used for the determination of the magnetic susceptibility of solutions or the concentration of a solute by using the manganese(II) solution as a standard solution.

A Raman microprobe spectrometer that could be installed in the bore of a cryogen free super-conducting magnet (10 T) was designed and constructed for the investigation of the external magnetic field effect on the Raman spectra of molecular aggregates in solutions and at interfaces. The performance of the present instrument was demonstrated by measuring the magnetic field effect (0 - 10 T) on the resonance Raman spectra of diprotonated meso-tetra-(sulfonatophenyl)porphine aggregates in an acidic solution. The Raman shifts of the aggregates were not significantly influenced even in 10 T. However, the relative intensity of 1123 cm(-1) peak (nu(C(a)-N)) was interestingly enhanced about 20% under the magnetic fields higher than 2.5 T.

The complex formation of Cu(II) and Fe(II) with a hydrophobic ligand, 5-(octadecyloxy)-2-(2-thiazolylazo)phenol (TARC18), was investigated in the heptane/water system by the high-speed stirring spectrometry and the micro-two phase flow ESI/MS method. At first, the dissociation constant of TARC18 at the heptane/water interface was determined as pKa = 7.11. The interfacial complexation of the ligand with Cu(II) and Fe(II) under stirred conditions progressed with an increase of the pH. The experimental results showed that a 1:1 complex of Cu(II) and TARC18 was formed at the interface, but was hardly extracted into the heptane phase. On the other hand, the 1:2 complex of Fe(II) with TARC18 formed at the interface was significantly extracted into the heptane phase. The extraction constants and interfacial complex formation constants were estimated for the two systems from the experimental results, and all of the reaction schemes, including the interfacial reactions, were elucidated.

The direct measurement of the circular dichroism (CD) spectra of liquid/liquid interface has been achieved for the first time by the centrifugal liquid membrane (CLM) method combined with a conventional CD spectropolarimetry. In the sample chamber of the CD spectropolarimeter, a cylindrical glass cell containing small amounts of organic and aqueous phases was rotated at ca. 7000 rpm to generate a two-phase liquid membrane with a high specific interfacial area. The CD spectra of the J-aggregate of protonated 5,10,15,20-tetraphenylporphyrin formed at the toluene/sulfuric acid interface in the rotating cell have been measured. The results demonstrated the novelty and advantages of this method.

A microscopic system for the observation of reactions at a liquid-liquid interface was established, to which strong magnetic fields (0-0.4 T) could be applied with permanent magnets. In situ observation for the interfacial extraction of fluorescent and paramagnetic Eu(III) ion with 2-thenoyltrifluoroacetone (Htta) in dodecane was carried out. In the presence of oxalate (ox2-), micro-aggregates of Eu(III)-tta-ox complexes were generated in the aqueous phase before its extraction. When the micro-aggregates diffused to the dodecane-water interface, Eu(tta)3 was extracted with excess Htta in the dodecane phase. The microextraction process of the aggregates was observed as random flashes of Eu(tta)3 fluorescence at the dodecane-water interface. The single flash contained about 10(-16)-10(-14) mol of Eu(III). An application of magnetic fields made the flash frequency increase, which corresponded to an enhancement of interfacial Eu(III) extraction rate. The enhancement effect was attributable to the magnetophoresis of the paramagnetic microaggregates to the dodecane-water interface.

We propose a novel principle of velocity mass analysis of a micro-particle using magnetophoretic force. The new method can determine the mass of a particle from its magnetophoretic velocity change in a high magnetic field gradient in a low viscous medium such as air. In the present study, the new principle was demonstrated by the magnetophoretic acceleration of an aqueous manganese(II) chloride micro-droplet and the deceleration of a water micro-droplet in the atmosphere. The observed velocity change was analyzed taking into account the mass of the droplet through the acceleration term of the equation of motion. The experimental results proved that the inertia force in the magnetophoretic velocity of a micro-particle could be detected in air. The present method provided an innovative mass analysis method without any ionization of the sample.

Oleate-stabilized silver colloids of 5-nm-diameter were adsorbed to a toluene/water interface, and surface enhanced Raman scattering (SERS) spectra from these colloids were measured under the total internal reflection (TIR) condition. From the observed spectra, we examined the states of oleate ions and toluene molecules on silver colloids at the liquid/liquid interfacial region. The TIR-SERS spectra of oleate ions showed stronger peaks of the carboxylate group and the ethylene group than those of alkyl chains. From these results, it was found that the oleate ions were adsorbed on the silver surface in two different ways at the liquid/liquid interface; the carboxylate group adsorbed in the organic phase side, while the ethylene group adsorbed in the aqueous phase side. The shifts of the toluene in the interfacial SERS spectra were identical to those of bulk toluene, though the relative intensities among the peaks were not same. This result suggested that the toluene was adsorbed with a weak interaction, but was significantly enhanced by the local electromagnetic field at the colloid surface.

The recent development of new migration methods of micro-particles in liquids using various external fields is reviewed. The combination of a laser scattering force and a photothermal effect produced photothermal-conversion laser-photophoresis. A dielectric field generated in a planer or a capillary quadrupole electrode realized dielectrophoresis. Using a micrometer-scaled magnetic field gradient, the "Magnetophoretic velocimetry" of micro-particles was invented. Furthermore, the Lorentz force generated by combining an electric field and a magnetic field was utilized for electromagnetophoresis. These new methods were overlooked and the advantages in analytical use were discussed.

The interfacial adsorption and dimerization behavior of tetraphenylporphinatomanganese(III)chroride (Mn(TPP)Cl) in the toluene/water two phase system was studied. The absorption spectra of the porphyrin complex in the organic phase were blue shifted with increasing of pH in the aqueous phase, suggesting the formation of the mu-oxo dimer. The interfacial species in these systems were examined by means of UV/vis external reflection (ER) spectrophotometry. ER spectral maxima were also blue shifted with the increase in pH, whereas the shape of the ER spectra in the basic conditions was different from that of the mu-oxo dimer. The observed results suggest that the hydroxide-coordinated monomer, Mn(TPP)OH, was generated from the Mn(TPP)(H2O)+ at the interface under the basic conditions and that was further converted to the mu-oxo dimer, which was soluble into the toluene phase.

A new monitoring system for bacterial communities involving dimethylarsinic acid (DMAA) decomposition was provided by combining the MPN (Most Probable Number) method and RFLP (restriction-fragment-length polymorphism analysis). The abundance of DMAA decomposing bacteria was estimated by the MPN method using a bacterial culture medium, which included DMAA as the sole carbon source, indicating bacterial cell densities of 1700 cells/ml in Lake Kahokugata and 330 cells/ml in Lake Kibagata. After isolating the dominant bacteria using agar plates, the isolates were classified into some genotype groups by RFLP analysis using 16S rDNA sequences. Classification of the RFLP analysis indicated that 14 isolates of Lake Kahokugata were classified into 6 types, which included 2 dominant types related to genus Pseudomonas, while 8 isolates of Lake Kibagata displayed 6 types including one or two isolates. Moreover, the RFLP types were unique for each lake, suggesting that DMAA decomposing bacteria were specific for the aquatic environment related to the arsenic cycle. The activities of DMAA decomposition mostly matched with the RFLP type category of the isolates. Accordingly, combining the MPN method with the RFLP analysis will play an important role in elucidating the distributions and dynamics of the DMAA-decomposing bacterial community.

Crystal structure of 2-(5-bromo-2-pyridylazo)-5-diethylaminophenolatochloropalladium(II) (PdLCl) has been determined by X-ray diffraction. A crystal of PdLCl was constructed by two structural isomers of PdLCl molecules, which were particularly different in the positions of the carbon atoms at the diethylamino group, having cis-like or trans-like conformation for the carbon atoms. The molecules of PdLCl in the crystal were warped by a steric hindrance of the diethylamino group.

A simultaneous measurement technique for determining the migration velocity of a micrometer-sized particle in a capillary and the adsorption force to the inner surface of the capillary has been proposed. This technique is based on an electromagnetophoretic force being exerted on a micro-particle in an electrolyte solution, which is governed mainly by the electromagnetic buoyancy, when a homogeneous magnetic field is applied at a right angle to the electric current through the medium. By the electromagnetic buoyancy, micro-particles such as polystyrene, carbon and yeast were migrated perpendicular to the direction of the electric current and reached a fused-silica wall. A switching of the current direction could desorb the particle from the wall, and allowed to calculate the detaching force from the desorbing current. The migration velocity normalized to the size in the magnetic field of 10 T was increased in the order of yeast, carbon and polystyrene, while reflecting the decreasing order of the apparent conductivity of the particles. The desorption force could be measured up to 1 nN with a sensitivity of pN. The observed interaction forces of polystyrene and carbon were in the range of 250-600 pN with large deviations.

The dielectrophoretic (DEP) behavior of individual yeast cells (5-7 microm in diameter) in aqueous media was observed in a fabricated planar quadrupole microelectrode with a working area of 100 microm in diameter by an optical microscope. The yeast cells migrated in the radial direction in the working area. The DEP velocity of the cells increased as they approached the electrode. The DEP trajectory of the cells was analyzed with a theoretical equation derived previously, and the dielectrophoretic mobility was determined. The dielectrophoretic mobility was found to be affected by the viability of cells, the conductivity of the medium, and the binding of lectin protein (concanavalin A) to the cell surface. These DEP behaviors were analyzed based on the permittivities and conductivities of the cell interior and wall, and those of the medium.

The centrifugal liquid membrane (CLM) method, designed for the rapid sample injection, was applied to the kinetic study of the complexation of palladium(II) with 2-(5-bromo-2-pyridylazo)-5-diethyaminophenol (5-Br-PADAP) in the heptane/water system. The formation rates of Pd(II)-5-Br-PADAP complex, which existed only at the heptane/water interface, could be directly measured by the CLM method combined with transmission spectrophotometry. We found that the formation rates of Pd(II)-5-Br-PADAP complex were accelerated by the protonation of 5-Br-PADAP at the diethylamino-group that did not coordinate to Pd(II) ion and that the rate constant for the reaction of protonated 5-Br-PADAP at the interface was close to that in the aqueous phase. The present study demonstrated that the CLM method was easily applicable for the measurements of relatively fast interfacial reactions.