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In this study, we analyzed the influence of liquid sloshing on the pitching dynamics of flexible space structure with liquid on-board; the analysis considers the main body of a spacecraft as a rigid tank, the flexible appendages as two elastically supported elastic beams, and on-board liquid as an ideal liquid. The meniscus of the free surface of the liquid due to surface tension was considered. The Lagrangians of the main body of the spacecraft (rigid tank), liquid, and two beams (flexible appendages) were used in addition to assuming antisymmetric motion of the system; the frequency equations of the coupled system were obtained by applying the Rayleigh–Ritz method. Influence of moment of inertia of the main body on coupled motions of the flexible spacecraft was investigated. • Influence of liquid sloshing on the pitching dynamics of space structure was clarified. • Meniscus of free surface was considered. • Dynamics of the system is dependent on the moment of inertia of a main body of spacecraft. [ABSTRACT FROM AUTHOR]

Proposes the Pockels sensing technique for the measurement of electrical discharge. Advantages of the Pockels sensor; In-depth look at the Pockels effect of the electrical discharge; Details on the technique.

The dynamic stability of a liquid in a hemispherical tank covered with a plane diaphragm under vertical excitation was studied both theoretically and experimentally. In the analysis, the liquid was assumed to be incompressible, non-viscous, and irrotational, and the plane diaphragm was a clamped circular membrane. The equation of motion was derived using the Galerkin method. The central frequency and width parameter of the instability region, in which parametric vibration occurred, were obtained using the Hsu 's method. In the experiment, two silicon test membranes with a diameter of 500 mm and thicknesses of 0.22 mm and 0.34 mm, were used as test plane diaphragms. Each test membrane was uniformly tensioned in the radial direction at ten points that were uniformly spaced along the circumference of the edge of the membrane. The central frequency and instability regions were measured by vertically exciting the test tank and measuring their responses using a laser Doppler vibrometer. The effect of diaphragm tension on parametric instability regions is presented in this paper. A comparison of the instability region between the experimental and the theoretical results showed that they were in good agreement, including in the case of a free surface. • Effect of tension of diaphragm on the dynamic stability of hemi-spherical tank was clarified. • Instability regions were compared with experiment and analysis. • Two test membranes with different thickness were used in the experiment. • Mathieu equation was derived and the instability regions were determined by Hsu's method. [ABSTRACT FROM AUTHOR]

This study involved an analysis of the influence of liquid sloshing on the dynamics of flexible space structures with liquid on-board by considering the main body of a spacecraft as a rigid tank, the flexible appendages as two elastic beams, and on-board liquid as an ideal liquid. The meniscus of the free surface of the liquid due to surface tension was considered. The Lagrangians of the main body of the spacecraft (rigid tank), liquid, and two beams (flexible appendages) were used in addition to assuming symmetric motion of the system; the frequency equations of the coupled system were obtained by applying the Rayleigh–Ritz method. The influence of sloshing motion on the motions of the main body and flexible appendages of the spacecraft was investigated. The results indicated that the vibration characteristics of the coupled system were dependent on the static contact angle of the liquid, irrespective of whether the angle was larger/smaller than θ 0 =90°. [ABSTRACT FROM AUTHOR]

Experimental studies are conducted on the liquid sloshing characteristics in a spherical tank covered with a flexible diaphragm. A spherical acrylic tank with 145.2 mm radius is used as a test tank, and is filled with water. Silicon diaphragms, plane or hemispherical type, with 0.2 mm thickness are used as test diaphragms. The test tank is harmonically excited in the vertical direction by an electro-dynamic exciter. During the test, vibrations due to parametric instability occur when the excitation frequency is twice the natural frequency. Parametric instability regions for some natural modes are measured and are presented in the excitation frequency–excitation acceleration diagram for three cases: liquid surface is uncovered (i.e., free surface), covered with a plane diaphragm, and covered with a hemispherical diaphragm, with the volume of filling water being changed appropriately. [ABSTRACT FROM AUTHOR]

In this study, to simulate liquid sloshing in a spacecraft fuel tank, the effect of tension of a plane diaphragm on the hydroelastic coupled vibration of the liquid in a hemispherical tank was investigated both analytically and experimentally. In the theoretical analysis, the liquid was assumed to be incompressible, non-viscous, and irrotational, and the plane diaphragm corresponded to a clamped circular membrane. The influence of tension of the diaphragm on the natural frequency was investigated. In addition, its natural frequencies and vibration modes were compared with those of a liquid in a cylindrical tank. The comparison revealed that the natural vibration characteristics of a liquid in a hemispherical tank approximate those of a liquid with the same volume in a cylindrical tank. In the experiment, two silicon test membranes with diameters of 500 mm, one 0.22 mm thick and the other 0.34 mm thick, were used as plane diaphragms. Each test membrane was uniformly tensioned in the radial direction at ten points that were uniformly spaced along the circumference of the edge of the membrane. The natural frequencies were measured by tapping the test membranes with a finger and conducting an FFT analysis of the response. The vibration modes were measured by exciting the membranes acoustically and measuring their responses using a scanning laser Doppler vibrometer. A comparison between the experimental and theoretical results showed that they were in good agreement, even in the case of an empty tank. This demonstrates the validity of the theoretical analysis and accuracy of the experimental results. • Investigated effect of tension on hydroelastic coupled vibration of liquid in tank covered with plane diaphragm from both theoretically and experimentally. • Two test silicon membranes used as plane diaphragms were uniformly tensioned. • Sloshing characteristic of liquid in a hemispherical tank covered with plane diaphragm can be approximated with that of liquid having the same volume in a cylindrical tank. • Experimental results and theoretical results showed good agreement. [ABSTRACT FROM AUTHOR]

Abstract: The dynamic stability of a vertically standing cantilevered beam simultaneously excited in both horizontal and vertical directions at its base is studied theoretically. The beam is assumed to be an inextensible Euler–Bernoulli beam. The governing equation of motion is derived using Hamilton's principle and has a nonlinear elastic term and a nonlinear inertia term. A forced horizontal external term is added to the parametrically excited system. Applying Galerkin's method for the first bending mode, the forced Mathieu–Duffing equation is derived. The frequency response is obtained by the harmonic balance method, and its stability is investigated using the phase plane method. Excitation frequencies in the horizontal and vertical directions are taken as 1:2, from which we can investigate the influence of the forced response under horizontal excitation on the parametric instability region under vertical excitation. Three criteria for the instability boundary are proposed. The influences of nonlinearities and damping of the beam on the frequency response and parametric instability region are also investigated. The present analytical results for instability boundaries are compared with those of experiments carried out by one of the authors. [Copyright &y& Elsevier]

Abstract: To ensure the safety of aircraft seats, it is mandatory to perform a dynamic test under an acceleration pulse prescribed by the Federal Aviation Administration. This paper proposes a design method for a decelerator. The design involves the piling up of paper sandwich panels for use in a drop test. First, a quasi-static compression test of paper core sandwich panels was conducted to examine the displacement–load curve, from which the absorption energy of the panels was deduced. Then, a piled-up configuration of panels was designed via a method based on the rigid, perfectly plastic, locking model proposed by Reid and Peng—in which the dynamic effect of the panel is considered when the core height is constant or variable—under the assumption that the decelerator crushes in descending order starting with the upper panel. Second, a drop tower test was conducted to determine whether the designed decelerator achieves the required acceleration pulse. The results of the proposed method were compared with those of the decelerator design method by Shoji et al. based on the dynamic absorption energy of the panels. The test results indicate that decelerators designed with the proposed method—based on the absorption energy derived from a simple static compression test and employing the effect of dynamic crushing—can produce identical results to those designed with the method by Shoji et al., which is based on the absorbing energy derived from a complicated dynamic compression test. [Copyright &y& Elsevier]

Pipes of 3003/4043 clad aluminum alloys are used in air conditioning systems and are exposed to flowing relatively high-temperature solutions (353 - 373 K). In the present investigation, the corrosion behavior of pure aluminum and 1050-, 3003-, and 4043-aluminum alloys was examined by immersing in 1.57 × 10−3 kmolm−3-CuSO4 and 0.57 kmolm−3-KCl solutions at 363 K for 1 week. Mass losses of the specimens during the immersion were measured after removing corrosion products, and the specimen surfaces were characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). Mass losses of all specimens examined were 0.1 - 0.7 % in the Cl− solution and 2-3 % in the Cu2+ solution. The mass losses in a solution including both Cl− and Cu2+ ions at the same concentrations were 4 - 8 %, showing a synergistic effect of Cl− and Cu2+ ions. This effect was more with higher concentrations of Si in the Al alloys. The SEM and EDS analysis showed that Cu particles are deposited on Al phases and Fe-enriched areas of the specimen surfaces in the Cu2+ solution, while deposited on Si-enriched areas as well as on Al phases and Fe-enriched areas in the Cl−/Cu2+ solution. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Free vibration analysis of a spherical liquid drop attached to a conical base is presented. Assuming the liquid is incompressible and inviscid, and introducing a velocity potential, axisymmetric and asymmetric vibration characteristics are clarified, considering two liquid contact conditions: slipping edge and anchored edge. In the numerical calculations, for a wide range of conical base apex angles, the natural frequency and vibration mode of a liquid drop are presented. From these parameters, the vibration characteristics of a liquid drop attached to a conical base with general apex angle can be easily predicted. When the apex angle tends to 180°, natural frequencies are found to converge to those of a spherical drop under both slipping and anchored edge conditions, except in the axisymmetric mode with meridian mode number m=0 in the anchored edge case and asymmetric mode m=1 and n=1 in the slipping edge case. [Copyright &y& Elsevier]

Abstract: Unexpected vibrations on a cylindrical filter made of nonwoven fabrics were clarified experimentally. Two types of filter with length L=1.8m and 3.7m, both 45cm in diameter and 1.08mm in thickness, were used. This is a new type of aeroelastic vibration phenomenon because the filter is a closed cylindrical vessel. In addition, the flow velocity of inner air was very slow and inner air flowed out slowly from the filter surface. The velocity distribution of air flow from a fan duct as well as the frequency and amplitude of the filter vibration were measured for two types of filter. By setting up a roll core panel at the outlet of the fan duct, we could rectify the outflow and suppressed the vibration of the shorter filter with L=1.8m. However, this method was not adequate for the longer filter with L=3.7m, and we could suppress the vibration by shielding the inner surface of the filter at the top region. [Copyright &y& Elsevier]

An effective countermeasure against vibration under limitation of volume and weight of small satellites is to insert thin polyimide tape between structural elements, especially for structural vibration of a small satellite during its launch. In this study, we deal with three types of aluminum elastic beams clamped on an aluminum rigid base. To explain dynamic damping properties of thin polyimide tapes inserted between structural elements based on our experimental data, we first develop a mathematical model, which can be applied to FEM analysis. Although this model generally depends on both the number of laminated tape layers and frequency, it shall be modified to a special model, which only depends on frequency but not depend on the number of layers. Finally, using a new test beam, the validity of the proposed mathematical model is demonstrated. [ABSTRACT FROM AUTHOR]

PTEN-induced kinase 1 (PINK1), which is identified as the gene transactivated by the tumor suppressor PTEN, has been found to be one of the causative genes in Parkinson’s disease (PD). In order to understand PD, rodent models containing affected Pink1 such as loss-of-function mutations have been exploited. Recently, natural antisense RNA of PINK1 has been demonstrated to be involved in the regulation of the PINK1 locus. However, no antisense RNAs of Pink1 except for human have been reported so far. Therefore, in the present study, while searching for the Pink1 antisense RNAs in mouse, we found that the antisense RNAs are transcribed from a mouse genomic region corresponding to the human region from which the antisense RNAs are produced. Further, we investigated the localization of the antisense RNAs in mouse brain using in situ hybridization; this demonstrated that the antisense RNAs were localized in the regions of brain where the Pink1 mRNA was found. In addition, the mRNA and antisense RNAs were found more densely in the hippocampus than in the other brain regions in newborn and 1-week-old mice, while those RNAs were found uniformly in the mouse brain regions of embryo day (E) 14, E17, and 8-weeks-old. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Experimental studies have been conducted to clarify the influence of horizontal harmonic excitations on the dynamic stability of a slender cantilever beam under vertical harmonic excitation. Three kinds of aluminum test beams with rectangular cross section have been used. The test beam being clamped at one end and free at the other end, was vertically stood, and was harmonically excited to both vertical and horizontal directions simultaneously. The direction of the horizontal excitation was taken parallel to one of the beam side faces, i.e. two directions were considered as X and Y directions which have the largest and smallest flexural rigidity, respectively. By varying the horizontal excitation amplitude, keeping the amplitude of excitation in the vertical direction, the influence of the horizontal excitation has been investigated on the principal instability regions in which unstable vibration of the fundamental vibration mode occurs. The excitation frequency in the vertical excitation was taken around twice the fundamental natural frequency 2 f Y 1 in smallest rigidity direction, while that in the horizontal direction was taken around both the fundamental natural frequency f Y 1 and twice of it 2 f Y 1. Obtained experimental results present useful fundamental data for aseismatic design of structures under earthquake containing both vertical and horizontal excitation components. [ABSTRACT FROM AUTHOR]

Distribution of samarium (Sm) in mice was investigated after inhalation exposure to Sm2O3 particles of 5 μm diameter and 15 mg/m3. Concentrations of Sm were determined by ICP-MS. Samarium was mainly distributed in lung, and the concentrations were varied, depending on the exposure length and time passed following final inhalation. Samarium concentrations in bone were lower than in lung, however, increased after cessation of the inhalation, suggesting that a part of Sm in lung was transported to bone via the blood stream. [ABSTRACT FROM AUTHOR]

Abstract: Effect of significant retardation of the phase velocity in a microwave microstrip resonator has been found and utilized for detection of spatial-dispersion phenomena in superconductors, which should be pronounced when the phase velocity became less than the Fermi velocity. The effect is explained by the influence of the fine fringes of a strip near of which the high values of curvature can appear for the system of coordinates introduced to find solutions. This leads to a spatial dependence of the phase velocity on the Lamé coefficients (metric coefficients) of the curvilinear system of coordinates and can decrease the velocity significantly. Comparative estimates of the spatial effects for single-crystal high-T c (YBaCuO), Nb, and Cu samples were obtained from measurements of the resonant frequency depending on a position of the sample in the field. [Copyright &y& Elsevier]

Abstract: The effect of enhancement of nonlinear properties of superconducting films is found in low-frequency magnetic field. Harmonic mixing of the electromagnetic radiation is detected. These results provide an argument in support of a new approach to design the active superconducting elements. A low-frequency oscillating magnetic field directed perpendicularly to the film surface forms an unstable vortex structure in the film. The frequency multiplication is intensified in the vortex unstable state. A transition of the vortex structure into the ground state synchronized by an external resonant circuit causes the generation of the electromagnetic radiation. Main advantage of these oscillators over Josephson junctions is high power emitted into a broadband system. [Copyright &y& Elsevier]

Recently, it has been reported that antisense RNAs are transcribed from a large number of genes in various species including human and mouse. The Prdx2 gene, which is indicated to be involved in signal transduction related to platelet-derived growth factor as well as to protection from oxidizing agents, has been shown to produce sense and antisense transcripts. To obtain clues for possible roles of Prdx2 antisense transcripts, we have performed Northern blot analysis and in situ hybridization on tissues of 8-week-old C57BL/6J mice. The Northern blot analysis revealed that major parts of sense and antisense transcripts were poly(A–)-RNA. The analysis of the fractionated RNA of fibroblasts indicated that the poly(A–)-RNA would be localized in the cytoplasm of cells. The in situ hybridization demonstrated that the sense and antisense transcripts were localized in almost the same limited areas of brain, testis, and spleen. It also revealed that the sense and antisense transcripts coexisted in Purkinje cells. In thymus and stomach, the antisense transcripts were detected, but sense transcripts were not. When tissues of BALB/c mice were examined by in situ hybridization, the observations were essentially the same as those of C57BL/6J except that it appeared that the amounts of sense and antisense transcripts in testis of BALB/c were greater than those in C57BL/6J, and that the amounts of antisense transcripts in stomach of BALB/c were much smaller than those in C57BL/6J. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Enhanced gamma (Δγ) ray dose rates due to 222Rn progeny wet deposited on the ground surface measured at six monitoring sites in Japan were statistically analyzed to investigate their temporal and spatial variations. Variations of Δγ ray dose rates indicated significant regional differences between the sites on the Sea of Japan coast and those located inland and on the Pacific coast in Japan. At the sites located on the Sea of Japan coast, significant seasonal variation was evident, with higher dose rates in autumn and winter, and lower dose rates in summer. In contrast, however, no significant seasonal variation was observed at the inland and Pacific coast sites in Japan. The variation of Δγ ray dose rates was characterized by three major factors: climatologically changed air masses arriving in Japan, variation of 222Rn and its progeny concentrations in the air column, and the regional characteristics of precipitation. It is evident that the contribution from local 222Rn to Δγ ray dose rates was smaller than those from continental 222Rn. Meso-scale atmospheric disturbance, however, was suggested as an important process for extremely high Δγ ray dose rates, possibly by the accumulation of additional local 222Rn with stronger convergence. It is therefore possible that the variation of Δγ ray dose rates reflects the chemical climatology of 222Rn and its progeny. [Copyright &y& Elsevier]

In order to shift the frequencies of a liquid with a free surface away from dangerous system frequencies, the surface of the liquid may be covered with a flexible membrane or a thin elastic plate. The magnitude of such a frequency shift depends on the parameters of the liquid and those of the structural system and should be known for the design of an aerospace vehicle. For that reason, we treat a rigid circular cylindrical large aspect ratio container filled with incompressible and viscous liquid, being covered by an elastic structure. The coupled frequencies and the decay magnitudes are determined for the lower vibration modes. The fact that we deal with a large aspect ratio tank, where the liquid close to the bottom of the container exhibits only small velocities, suggests that the adhesive bottom conditions may be deleted, while those at the side wall of the container are mainly contributing to the damping and are for that reason considered in the analysis. We determine the complex frequencies of the hydroelastic system. The results show that the coupled frequencies increase with increasing liquid height ratio and reach soon a nearly constant value, which is being reached much earlier for higher modes. The decay magnitude also reaches quickly a constant value. Higher modes are damped out fast. In addition, it was found that the coupled oscillation frequencies are always larger than those of the frictionless liquid, and that the difference between them decrease considerably with increasing mode numbers. [Copyright &y& Elsevier]

Abstract: Coupled free vibration analysis has been performed on a cantilever thin elastic plate carrying a liquid drop attached on its arbitrary point in a zero-gravity environment. A liquid drop, having slipping edge boundary condition on the plate, has been treated as an inviscid ideal liquid with hemi-spherical shape. By using Rayleigh–Ritz method, coupled hydroelastic problem has been rendered into an eigenvalue problem, from which one can obtain coupled natural frequencies and modes of vibration. Since we have treated an attached drop as an ideal liquid drop not as added rigid mass or ‘mass–spring’ system, the problem consists of coupled system between a plate and a liquid drop, which have both multi-degrees of freedom. In the numerical calculations, present results have been compared with the results in which a liquid drop have treated as a ‘mass–spring’ system which has previously been presented by the authors. [Copyright &y& Elsevier]

Drinking water in developed countries is usually treated by the water-purification system, while in developing countries untreated natural water such as well water, river water, rain water, or pond water are used. On the other hand, many kinds of mineral water bottled in plastic containers are sold as drinking water with or without gas in urban areas in many countries. Seawater under hundreds meters from the surface is also bottled and sold as drinking water with advertising good mineral balance. Various element concentrations in water samples for drinking were analyzed, and then it was considered the effects of elements on human health. [ABSTRACT FROM AUTHOR]

Abstract: A new beam line for photonuclear reaction experiments using tagged photons has been constructed to take advantage of the completion of the 1.2-GeV STretcher Booster (STB) ring at the Laboratory of Nuclear Science (LNS), Tohoku University. A photon tagging system was installed at the end of the new beam line. It provides bremsstrahlung tagged photon beams in an energy range from to at the incident electron energy with an energy resolution of . The tagged photon intensity is available for typical photonuclear reaction experiments. We introduce the basic parameters of the tagged photons by showing the commissioning data. [Copyright &y& Elsevier]

It has been reported that not only selective alveolar-bone resorption, but also receptor activator of nuclear factor kappa B ligand (RANKL) expression is induced on the compressed side of an orthodontically moving tooth. Numerous reports have described the pharmacological acceleration of tooth movement (TM) through the activation of osteoclasts. However, because of rapid flush out by blood circulation, daily systemic administration or daily local injection is needed. Previously, we discovered that every-3-days OPG gene transfer to the periodontal-tissue inhibited RANKL-mediated osteoclastogenesis and diminished experimental TM. Therefore, we hypothesized that local RANKL gene transfer into the periodontal tissue would accelerate TM. The upper first molars of 6-week-old male Wistar rats were moved palatally using fixed orthodontic wires. The inactivated hemagglutinating-virus of Japan (HVJ) envelope vector containing the mouse RANKL expression plasmid was injected periodically into the palatal periodontal tissue of the upper first molars during TM. Local RANKL gene transfer significantly enhanced RANKL expression and osteoclastogenesis in periodontal tissue without any systemic effects. The TM rate was significantly increased in the RANKL gene transfer side. In conclusion, we demonstrated that transfer of the RANKL gene to the periodontal-tissue activated osteoclastogenesis and accelerated the amount of experimental TM. Local RANKL gene transfer might be a useful tool not only for shortening orthodontic treatment, but also for moving ankylosed teeth where teeth, fuse to the surrounding bone.Gene Therapy (2006) 13, 678–685. doi:10.1038/sj.gt.3302707; published online 5 January 2006 [ABSTRACT FROM AUTHOR]

Objectives: To investigate the prevalence of anaemia and iron deficiency and vitamin A status among school-aged children in rural Kazakhstan and identify factors associated with anaemia in this population.Design: A cross-sectional design.Setting: School-aged children in rural Kazakhstan.Subjects: Socio-economic and anthropometric information was collected from 159 school-aged children living in the Kzyl-Orda region of Kazakhstan. Blood samples were collected and the concentrations of haemoglobin (Hb), serum iron, serum ferritin (SF), erythrocyte protoporphyrin (EP), serum retinol and beta-carotene, total iron binding capacity (TIBC), transferrin saturation (TS) and other haematological indices were measured.Results: Among the 159 children, the prevalence of anaemia and iron deficiency defined by the multiple criteria model (SF, TS and EP) was 27% and 13%, respectively. Nine per cent had iron-deficiency anaemia and 21% had serum retinol value < 1.05 micromol l(-1). Mean SF and serum iron concentrations and TS were significantly lower in anaemic children than in their non-anaemic peers, while TIBC and EP were significantly higher in children with anaemia. Hb was significantly correlated with serum iron and retinol concentrations. Serum retinol and SF concentrations and mean corpuscular volume were significantly correlated with Hb by multiple regression analysis.Conclusions: Anaemia among school-aged children in rural Kazakhstan appears to be related to iron indices and vitamin A status. [ABSTRACT FROM AUTHOR]

The measurement of longitudinal momentum distribution for two-proton removal from the proton-drip line nucleus 17Ne with a Be target at 64 A MeV is reported. The observed narrow momentum distribution and the large interaction cross-section suggests the formation of a two-proton halo. The data analyzed within the Few-body Glauber model suggests a significant probability of the two valence protons to abnormally occupy the 2 s1/2 orbit, indicating its lowering in proton-rich nuclei. [ABSTRACT FROM AUTHOR]

Abstract: The complex frequencies of a viscous spherical drop where part of the free surface is embedded in a rigid spherical cap of the same radius have been determined as a function of the cap angle and the free surface tension parameter. With increasing cap angle , the oscillation frequencies and decay magnitudes increase. This is also true for liquid drops of larger surface tension parameters. It also could be found, as has been found previously for a free floating sphere of viscous liquid, that the oscillations may cease to exist for certain diameters and low surface tension parameters, a fact not present in the treatment of frictionless liquid. In such cases, the captured liquid globule performs just an aperiodic motion. Three different liquid systems have been considered. In addition, the response of a captured spherical drop due to harmonically forced vertical translational excitation of the cap has been determined. Only a liquid sphere embedded in a spherical cap of the same radius has been evaluated numerically. The results reveal that for the mode the geometry of a liquid sphere in a spherical cap of equal radius represents—depending on the magnitude of the cap—for small surface tension parameters , a stable configuration, while for large -values the spherical geometry is unstable, indicating that for those large cases the free liquid surface assumes a different geometry. [Copyright &y& Elsevier]

Abstract: If the free liquid surface of a viscous liquid is completely covered by an elastic structure, the damped natural frequencies of such a hydroelastic system are shifted to values larger than those obtained with a free liquid surface. In addition, the sloshing of the liquid is considerably reduced and exhibits, depending on the tension or stiffness of the covering elastic structure, smaller deflection amplitudes and drastically reduced liquid forces and moments participating in the dynamic behavior of the system. The hydroelastic frequencies of a viscous liquid in a circular cylindrical tank of moderate to large liquid height aspect ratio may be covered completely by a flexible membrane or an elastic plate, and exhibit an increase with increasing liquid height ratio h/a. In addition, the damping becomes stronger with the increasing h/a and remains––as the frequency does—nearly constant from a certain height ratio onwards. This indicates that from a certain moderate liquid height ratio neither frequency nor damping does change considerably, since in the lower portion of the container the velocity distribution and its change remain quite small. With the increase in the membrane tension parameter , the magnitude of both natural frequency and the decay of the oscillations increase. The same happens for the increase of the stiffness parameter . In addition, higher modes show larger damping. [Copyright &y& Elsevier]

Rock salt and limestone are studied to determine their suitability for use as a radio-wave transmission medium in an ultrahigh energy (UHE) cosmic neutrino detector. A sensible radio wave would be emitted by the coherent Cherenkov radiation from negative excess charges inside an electromagnetic shower upon interaction of a UHE neutrino in a high-density medium (Askar’yan effect). If the attenuation length for the radio wave in the material is large, a relatively small number of radio-wave sensors could detect the interaction occurring in the massive material. We measured the complex permittivity of the rock salt and limestone by the perturbed cavity resonator method at 9.4 and 1 GHz to good precision. We obtained new results of measurements at the frequency at 1.0 GHz. The measured value of the radio-wave attenuation length of synthetic rock salt samples is 1080 m. The samples from the Hockley salt mine in the United States show attenuation length of 180 m at 1 GHz, and then we estimate it by extrapolation to be as long as 900 m at 200 MHz. The results show that there is a possibility of utilizing natural massive deposits of rock salt for a UHE neutrino detector. A salt neutrino detector with a size of 2 × 2 × 2 km would detect 10 UHE neutrino/yr generated through the GZK process.© 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The measurement of one- and two-neutron removal cross section and longitudinal momentum distribution of 19C after reaction with a Be target at 64 A MeV are reported. This is the first study of the two-neutron removal for the nucleus. Besides that, the present one-neutron removal study helps to confirm negligible energy-dependent effects. This comes from an agreement between data at high and low energy in a wide momentum range. A comparison of the two-neutron removal momentum widths presented for Carbon isotopes shows interesting feature for 19C. [Copyright &y& Elsevier]

The natural frequencies and mode shapes have been investigated for a frictionless spherical liquid globule where part of the free surface is embedded in a spherical cap of the same radius. Five different liquid systems have been considered. With increasing cap angle α and higher modes n, the natural frequencies increase. The different mode shapes exhibit a drastic change of frequencies. In addition, the response of the captured spherical drop due to harmonically forced translational excitation of the rigid cap has been determined for the two major directions. [Copyright &y& Elsevier]

Environmental conditions were evaluated by element concentrations in hair of children living near the Aral Sea. Hair samples were provided by 63 children living near the Sea (K-district), and 143 children living about 600 km from the Sea (Z-district). PIXE was applied for the determination of elemental concentrations. The concentrations of Br, Na, Hg, and Ni were higher in K-district, and those of Al, Ca, Cr, P, S, and Si were higher in Z-district than in the other district, respectively. It is considered that these results reflect the environmental situation. [ABSTRACT FROM AUTHOR]

The first measurement of the two proton removal, cross section and momentum distribution, with a Be target at 66 A MeV are reported. The momentum distribution shows a width of 168±17 MeV/c (FWHM) that is much narrower than the width expected from a normal nucleus (f∼290 MeV/c). The proton removal cross-section has been determined to be 191±48 mb. Analysis of present data together with interaction cross section indicates significant s-wave probability of the two valence protons. This suggests a two-proton halo in 17Ne. [Copyright &y& Elsevier]

Coupled free vibration analysis has been performed on a cantilever thin plate carrying a spring–mass system attached on an arbitrary point by using Rayleigh–Ritz method. Influence of an attached ‘spring–mass’ system, i.e., attached position, relative values of mass and spring constant, on the coupled vibration characteristics of the system has been clarified comparing with those of uncoupled ones. Optimal attached position to maximize coupled plate natural frequency is also investigated and shown in contour diagrams. The influence of an attached mass has also been investigated, as the limiting case whereby the spring stiffness of the ‘spring–mass’ system approaches infinity. [Copyright &y& Elsevier]

Unlabelled: The Aral Sea region is a natural area seriously polluted by human activities. In addition to the increased prevalence of diverse chronic diseases in children, the risk of developing urolithiasis is reported to be high in this region. This study was undertaken to clarify the prevalence of hypercalciuria in children of the Aral Sea region. A group of 205 children living in Kazalinsk, close to the Aral Sea, and a group of 187 children living in Zhanakorgan, far from the Aral Sea, were screened for hypercalciuria. Urinary sodium excretion (sodium per creatinine, uNa/Cr) in addition to calcium excretion (calcium per creatinine, uCa/Cr) was also calculated for each subject. Mean uCa/Cr (mmol/mmol) and uNa/Cr (mmol/mmol) excretions were significantly higher in Kazalinsk than in Zhanakorgan (uCa/Cr: 0.75 +/- 0.74 and 0.33 +/- 0.30; uNa/Cr: 3.54 +/- 2.27 and 2.89 +/- 1.69, respectively, mean +/- SD, p < 0.01). Hypercalciuria regarded as an uCa/Cr of more than 0.703 was observed in 79 out of 205 Kazalinsk children (38.6%) while this was seen in only 24 out of 187 Zhanakorgan children (12.8%). Linear regression analysis revealed a direct positive correlation between urinary calcium and sodium excretion (p < 0.01) in Kazalinsk children.Conclusion: The prevalence of hypercalciuria in children around the Aral Sea region is extremely high. This may be associated with excessive intake of calcium and sodium, or due to impaired renal tubular function caused by toxic chemicals. Therefore, hypercalciuria that may lead to urolithiasis should be taken into account when considering the health problems of this area. [ABSTRACT FROM AUTHOR]

We have developed a single-sided silicon strip detector with a sensitive area of 64×64 mm2 as a real-time, fast and medium-segmented hodoscope for particle physics experiments in high beam background environment. The signal of each 2 mm wide readout strip was integrated in a hybrid preamplifier with a decay constant of 10 μs. The output was then amplified 20 times and shaped to a peaking time of ∼50 ns in a shaping amplifier. The performance was first examined on a test bench, and then with an intense π−/μ−/e− beam. The Equivalent Noise Charge (ENC, 1σ) at the preamplifier input was ∼2000e (9% of the signal for single minimum ionizing particle ∼22 000e) at low beam rate, and increased by 10% (or 20%) at a high rate of 150 kHz (300 kHz) per readout-strip. As the cable length (L) from silicon board to preamplifier increased, the ENC increased from 2000e for L=0.2 m to 2600e for 0.5 m, 3500e for 1 m, 3800e for 1.5 m, and 4200e for 2 m. [Copyright &y& Elsevier]

A linear free hydroelastic vibration analysis of a frictionless liquid with a free surface contained in a cylindrical tank with a flexible bottom has been performed. The side-wall has been treated as rigid and the effect of surface tension taken into consideration. The container bottom was treated as a membrane, while for the free liquid surface the effect of two contact line conditions has been investigated. One edge condition was that of a slipping contact line, while the other one treated the contact line as fixed, ie., an anchored edge. The vibration characteristics of a membrane–liquid coupled system have been investigated for various system parameters, i.e., membrane tension parameter T, liquid surface tension parameter σ, material density parameter ρ, liquid height ratio ℓ0 and vibration mode numbers m and n. The degree of coupling between a membrane and a liquid was represented with vibration mode diagrams as well as with frequency diagrams. For axisymmetric coupled vibrations with anchored edge condition, vibration mode exchanging of both a membrane and liquid free surface with membrane bottom tension parameter T has been investigated. An interesting phenomenon which is only observed for a flexible bottom container and an anchored edge free surface condition is presented. [Copyright &y& Elsevier]

We have measured magnetic susceptibility and [sup 51] V NMR of CaV[sub 2] O[sub 4] , a model substance for a frustrated S = 1 spin chain with competing first- and second-neighbor anti-ferromagnetic interactions. Both the low-temperature magnetic susceptibility and the NMR Knight shift did not go down to zero as the temperature was lowered, suggesting that a spin gap is not present in CaV[sub 2] O[sub 4] . The absence of a spin gap gives us a clear contrast to the case of the nonfrustrated spin chains, which should have the Haldane gap. Recently published theoretical results for S = 1 XY or XXZ spin chain indicate that the gapless chiral phase could appear in a relatively broad region. Experimental results are discussed in terms of these theoretical predictions. A spin-freezing anomaly was observed at 20 K, reflecting the spin-frustrating nature of the system.PACS Nos.: 75.30, 75.50 Nous avons fait des mesures de susceptibilité et RMN sur le [sup 51] V dans le composé CaV[sub 2] O[sub 4] , une substance modèle pour une chaîne de spin frustrée S = 1 avec interactions rivales, plus proche voisin et antiferromagnétique deuxième plus proche voisin. À basse température, ni la susceptibilité, ni le déplacement RMN de Knight ne tendent vers zéro avec la température, suggérant l'absence d'un intervalle (gap) de spin dans le CaV[sub 2] O[sub 4] . L'absence d'un tel intervalle contraste avec le cas des chaînes de spin non frustrées qui devraient montrer un intervalle d'Haldane. Des résultats théoriques récemment publiés pour des chaînes de spin XY ou XXZ, S = 1, montrent que la phase chirale sans intervalle pourrait exister sur une région assez vaste. Nous analysons les résultats expérimentaux à la lumière de ces prédictions théoriques. Une anomalie de gel de spin a été observée à 20 K, reflétant la frustration de spin du système. [Traduit par la rédaction] [ABSTRACT FROM AUTHOR]

Background:The potential role of superantigens in inflammatory bowel disease (IBD), particularly Crohn disease, has been broached in studies of the functions of T cell receptors. Staphylococcal cells have been found in intestinal lymph follicles of IBDs. To clarify a role of staphylococcal superantigens in IBD, we attempted to determine whether Staphylococcus aureuscould be detected in intestinal mucosa, including surgical specimens and lymph follicles of initial cases. Methods:One-hundred-and-six colonic and ileal specimens were obtained from 38 Crohn disease, 25 ulcerative colitis and 36 non-IBD patients through therapeutic surgery or endoscopic biopsy. In Crohn disease, 23 surgical specimens and 11 biopsy specimens from initial cases were included. DNA was extracted with phenol-chloroform after homogenization and proteinase K treatment in 73 mucosal specimens. Using an inverted microscope, lymph follicle tissue was microdissected from the remaining 33, mostly biopsy, specimens. DNA was then extracted by freeze-thawing. A coagulase gene characteristic of S. aureuswas sought. A nested polymerase chain reaction was performed utilizing primers that amplify a region of the coagulase gene. Polymerase chain reaction products were analyzed with polyacrylamide gel electrophoresis. Results:Only one surgically resected colonic specimen, from a 42-year-old male ulcerative colitis patient, registered positive staphylocoagulase amplification. Conclusions: Staphylococcal superantigens are not involved in either the early lesions or the established lesions of Crohn disease. However, S. aureusinfection occasionally may occur during the course of IBD. [ABSTRACT FROM AUTHOR]

Preferential involvement of the appendix has recently been confirmed in ulcerative colitis. Since the appendix is an aggregate of lymph follicles, this new observation implies a critical role of the lymph follicles, of both the large bowel and the appendix, in an etiopathogenesis of ulcerative colitis. This report presents two cases of ulcerative colitis in which lymph folliculitis and lymphoid hyperplasia were observed. Lymph folliculitis was observed endoscopically in a border between an established lesion and an uninvolved area. Case 1, proctitis type, relapsing remitting, mild in severity, showed lymph folliculitis in a proximal border of an established rectal lesion. Case 2, with left-sided colitis, mild in severity, had a skip appendiceal orifice inflammation. Lymph folliculitis was observed in the cecum surrounding established appendiceal orifice inflammation. In both cases, lymphoid hyperplasia was observed in an uninvolved area with clear vascular patterns. These two cases clearly demonstrate the involvement of gut lymph follicles in ulcerative colitis. Lymph folliculitis and/or lymphoid hyperplasia was proposed to be early lesions in ulcerative colitis. In addition, the need for microbiology targeting lymph follicles of the large bowel and appendix is stressed in order to disclose the casual microbial agents in ulcerative colitis. [ABSTRACT FROM AUTHOR]

Background: There is currently no information regarding microbial agents inside the intestinal lymph follicles. Methods: Biopsy or resected specimens, mostly from macroscopically normal areas, were sectioned with a cryostat. DNA was extracted from microdissected samples, exclusively from the lymph follicle. Amplification of DNA was performed using universal primers designed from conserved regions of bacterial 16S ribosomal RNA (rRNA). Several clones with inserts of around 400 base pairs were subjected to DNA sequence analysis followed by a database homology search. Results: Bacterial 16S rRNA gene segments were detected in the lymph follicle in 2 of 14 (14%) non-inflammatory bowel disease (IBD) cases, 4 of 14 (28%) Crohn disease cases, and in 2 of 5 (40%) ulcerative colitis cases. Nineteen 16S rRNA gene segments were recognized in the eight positive cases. Five segments showed 100% identity to known bacterial 16S rRNAs, namely staphylococcus species, Streptococcus sanguis, and Paracoccus marcusii. However, the other 14 segments showed below 100% identity, indicating either the presence of unknown bacteria or of bacteria without known DNA data. No single identified or unidentified bacterium, characteristic of IBD, including Mycobacterium paratuberculosis and Listeria monocytogenes, was detected. Conclusions: The present study confirms the presence of bacterial 16S rRNA gene segments in human intestinal lymph follicles and paves the way for new investigations into the microbiology of the lymph follicle. Whether or not bacteria inside the lymph follicle is a primary stimulus in IBD has yet to be clarified. [ABSTRACT FROM AUTHOR]

Compares the in vitro metabolism of indinavir, an HIV protease inhibitor in liver microsomes of primates in the United States. Information on the metabolic pathways of indinavir; Metabolite formation rates among primates; Factors affecting species differences and similarities in drug metabolism.

Discusses the development of a testing apparatus to evaluate the characteristics of 10kArms class alternating current (AC) superconducting cables. Description of the testing apparatus; Adoption of the magnetization method using pick-up coils with the improvement of its sensitivity by reducing unnecessary output signal.

Autologous mixed lymphocyte cultures were set up from nylon non-adherent T-enriched lymphocytes and mitomycin C-treated spleen cells of individual ACI/N rats and the effect on the reaction (AMLR) of sera in the culture medium was studied with regard to the xenogeneic nature of the sera. Not only foetal calf serum, but also sera of adult human, horse and swine stimulated the AMLR response, but autologous or rat serum did not. Albumin fractions of these sera were also effective in inducing the AMLR response. Furthermore, the presence of xenogeneic serum in the culture medium was also required for the blastogenic response of AMLR-primed lymphocytes against the secondary stimulation with syngeneic spleen cells. Both autologous and xenogeneic sera, however, supported the Con-A response of the same responder cell population as used in the AMLR. These results substantiated our previous finding (Endho & Hashimoto, 1981) and suggest that two signals, one from autologous non-T cells and another from the xenogeneic factor in culture medium, are required to cause AMLR, at least in the rat system. [ABSTRACT FROM AUTHOR]

A case of ulcerative colitis in which the presence of Listeria monocytogenes was confirmed in the resected colon with polymerase chain reaction and subsequent Southern blot analysis and immunohistochemistry using antibody against Listeria is presented. The patient developed ulcerative colitis at the age of 59 years. Prednisolone, 50 mg/day, was given for severe ulcerative colitis. Later the disease became fulminating, indicating colectomy 4 months after the onset. Multiple sealed colonic perforations were observed. Numerous L. monocytogenes were found at the site of perforation, in fissures, and in cracks in the submucosa. This case indicates the possibility that L. monocytogenes contributes to the exacerbation of colitis to fulminating and colonic perforation. [ABSTRACT FROM AUTHOR]

Background: In an immunohistochemical study a higher rate of reactivity of intestinal tissues to the antibody against Listeria monocytogenes was reported in Crohn's disease as compared with controls. Methods: Seventy-six intestinal tissues, either therapeutically resected or biopsied, from 31 patients with Crohn's disease, 20 with ulcerative colitis, and 21 with non-inflammatory bowel disease were studied. DNA extracted from intestinal tissues by proteinase K treatment was used for nested polymerase chain reaction (PCR), using two sets of primers. PCR products were analyzed with agarose gel electrophoresis and subsequent Southern blot analysis. Results: Our amplification system could detect 9 pg of L. monocytogenes DNA. L. monocytogenes was detected in only one sample, that from a patient with ulcerative colitis. Conclusions: Our study does not support the etiologic significance of L. monocytogenes in Crohn's disease. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Aral Sea region is a natural area seriously polluted by human activities. Recent surveillance revealed the increased prevalence of diverse chronic diseases in children. AIMS: To investigate the function of renal tubules, which are most at risk of damage as a result of heavy metal intoxication, in children of the Aral Sea region. METHODS: A group of 205 children living in Kazalinsk, close to the Aral Sea, and a group of 187 children living in Zhanakorgan, far from the Aral Sea, were examined by means of random urine samples. Both urinary N-acetyl-beta-D-glucosaminidase (NAG; U/mmol Cr) and beta2 microglobulin (BMG; microg/mmol Cr) were calculated for each subject. RESULTS: Mean urinary NAG and BMG were both significantly higher in Kazalinsk than in Zhanakorgan (NAG: 0.77 (0.58) and 0.62 (0.37) U/mmol Cr; BMG: 41.8 (54.8) and 22.5 (20.4) microg/mmol Cr, respectively; mean (SD), p < 0.01). The number of children with abnormal values of NAG (>1.5 U/mmol Cr) was significantly more prevalent in Kazalinsk than in Zhanakorgan (7.9% and 2.6%, respectively, p < 0.05). CONCLUSION: Renal tubular function of children around the Aral Sea region is profoundly impaired. This should be taken into account when considering the health problems of this area. [ABSTRACT FROM AUTHOR]

The observation of longitudinal momentum distribution ( P||) from two-neutron removal in 19C with a Be target at 64 A MeV is reported. Analysis in terms of Glauber model considering 19Cgs( Jπ = 1/2+) shows that neutron evaporation is necessary to explain the data. [ABSTRACT FROM AUTHOR]