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We give estimates for the essential norm of a little Hankel operator with anti holomorphic symbol on weighted Bergman spaces of the unit ball in terms of the Bloch semi-norm of its symbol function.

Intercellular communication via GAP Junctions plays an important role in tissue homeostasis, apoptosis, carcinogenesis, cell proliferation and differentiation. Hepatocyte connexins (Cx) 26 and 32 levels are decreased during the de-differentiation process of primary hepatocytes in culture, a situation that is also characterized by a decrease in S-Adenosylmethionine (SAMe) levels. In this current study, we show that SAMe supplementation in cultured hepatocytes every 12h, leads to an up-regulation of Cx26 and 32 mRNA and protein levels and blocks culture-induced Cx43 expression, although it failed to increase Cx26 and 32 membrane localization and GAP junction intracellular communication. SAMe reduced nuclear β-catenin accumulation, which is known to stimulate the TCF/LEF-dependent gene transcription of Cx43. Moreover SAMe-induced reduction in Cx43 and β-catenin was prevented by the proteasome inhibitor MG132, and was not mediated by GSK3 activity. SAMe, and its metabolite 5'-methylthioadenosine (MTA) increased Cx26 mRNA in a process partially mediated by Adenosine A(2A) receptors but independent of PKA. Finally livers from MAT1A knockout mice, characterized by low hepatic SAMe levels, express higher Cx43 and lower Cx26 and 32 protein levels than control mice. These results suggest that SAMe maintains a characteristic expression pattern of the different Cxs in hepatocytes by differentially regulating their levels.

Mathematical and computational modelling are emerging as important techniques for studying the behaviour of complex biological systems. We argue that two advances are necessary to properly leverage these techniques: firstly, the ability to integrate models developed and executed on separate tools, without the need for substantial translation and secondly, a comprehensive system for storing and man-ageing not only the models themselves but also the parameters and tools used to execute those models and the results they produce. A framework for modelling with these features is described here. We have developed of a suite of XML-based services used for the storing and analysis of models, model parameters and results, and tools for model integration. We present these here, and evaluate their effectiveness using a worked example based on part of the hepatocyte glycogenolysis system.

In the study of the fission of actinide nuclei at low excitation energies including the spontaneous fission, it was found that the fragment mass distribution and the total kinetic energy (TKE) distribution consist of more than one component, in contrast to the simple single peak structure that is found in the fission at high excitation energies. 1– 6 This phenomenon is attributed to the existence of more than one fission path and is called the multi-modal fission. The mass and TKE distributions depend sensitively on the excitation energy and the position of the peaks of the mass distribution suggests the influence of the closed shell structure of the fragments. Therefore, it is supposed that the microscopic energy plays an important role for the manifestation of this phenomenon. It is a great challenge for us to understand this phenomenon in terms of nuclear many-body dynamics. Several authors studied the potential energy surface (PES) including the microscopic energy in a multi-dimensional parameter space that describes various nuclear shapes; one can deduce the possible fission paths by studying the location of the saddle points and the fission valleys in multi-dimensional parameter space. 7 With this method, they could explain the general trend of the position of the peaks of the mass distribution. The dynamical point of view is necessary to progress the study of the fission mode. We have applied the Langevin approach to the study of the fission modes in uranium nuclei and in fermium nuclei. 8–10 We studied the mass and TKE distributions and demonstrated that we can decompose the fission events into several components by tracing the Langevin trajectories. We also studied the isotope dependence and the excitation energy dependence of the fission mode. 8–10 In the previous studies, we adopted the wall-and-window type one-body friction as the dissipation mechanism of the nuclear fission dynamics. The validity of this dissipation mechanism has been demonstrated by one of the authors (T.W.) who studied the dissipation tensor dependence of the pre-scission neutron multiplicity and the mean TKE. 11–14 From the comparison of the results of the dynamical calculation with experimental data, they excluded the possibility of the two-body type dissipation to be the dominant mechanism by showing that it cannot reproduce the pre-scission neutron data and the TKE data simultaneously. On the other hand, they showed that the wall-and-window type one-body friction can reproduce both data reasonably well and concluded that it is a reasonable model for the dissipation mechanism of nuclear fission. There are other models that are of one-body nature, e.g. surface-plus-window formula, modified wall-and-window formula and chaos weighted wall formula. 15–17 Though there were no free parameters in the original derivation of the one-body friction, 18, 19 the strength has been modified frequently in order to reproduce some experimental data. For example, in the study of the light particle evaporation and the mass distribution, Schmitt et al. used the strength as a free parameter. 17 The modification itself should be acceptable when we take account of the simplicity of the model; it is a macroscopic model without any microscopic effect and it has no dependence on the temperature. However, when one modifies the strength of the nuclear dissipation just to reproduce only one physical quantity, it might be inappropriate to conclude that the deduced strength has definite physical meanings. It may reflect the other effects completely different from the dissipation, like the insufficiency of the model space. It is very important to compare many (at least more than one) physical quantities at the same time. Among the physical quantities that are measured in nuclear fission, the TKE and mass distributions are well investigated experimentally in many cases. In this study, we use these quantities to discuss the dissipation dependence of the fission modes. It is shown that the TKE distribution is, as was expected, directly connected to the strength of the dissipation and we can put some constraints on the strength of the dissipation. Furthermore, it is shown that the mass distribution changes rather drastically when one uses different models for the dissipation mechanism. These results demonstrate the importance and the usefulness of the dynamical approach to the study of the fission mode. Section 2 gives a concise description of our framework. Results are shown in Sec. 3 concerning the fission of 264 Fm nucleus at Ex = 20 MeV. Summary is given in Sec. 4. 2. Methods

Trace metals influence the absorption of each other from the diet and it has been suggested that the divalent metal transporter (DMT1) represents a common uptake pathway for these important micronutrients. However, compelling evidence from our laboratory suggests that DMT1 is predominantly an iron transporter, with lower affinity for other metals. Several studies have shown that increasing dietary iron downregulates DMT1. Interestingly, our current data indicate that zinc upregulates DMT1 protein and mRNA expression and also pH-dependent iron uptake. Transepithelial flux of iron was also increased and was associated with a rise in IREG1 mRNA expression.

Relating the pseudospin symmetry back to the Dirac equation through the framework of relativistic Hartree-Bogoliubov (RHB) theory, the pseudospin approximation in real nuclei is discussed. From the Dirac equation, the mechanism behind the pseudospin symmetry was studied and the pseudospin symmetry is shown to be connected with the competition between the centrifugal barrier (CB) and the pseudospin orbital potential (PSOP), which is mainly decided by the derivative of the difference between the scalar and vector potentials. With the scalar and vector potentials derived from a self-consistent relativistic Hartree-Bogoliubov calculation, the pseudospin symmetry and its energy dependence in real nuclei is discussed.

We have deduced the prescission time of hot nuclei as a function of the angular momentum from the light charged particle- and gamma ray-multiplicities measured simultaneously in coincidence with fully-damped binary decay fragments in the reaction of Ni-58 + Fe-56 at the incident energy of 10.0 MeV/nucleon. The prescission time was found to decrease as the angular momentum of the system increases. Theoretical calculations of the fissioning motion with the Langevin equation have shown that this dependence originates primarily from the change in the potential landscape due to the centrifugal energy. (C) 1998 Elsevier Science B.V.

It is shown that the part of the nuclear Hamiltonian which contains the products of pp and hh pair operators ~the scattering terms! and which has been usually neglected in the calculations of the giant dipole resonance turns out to be definitely important in the study of the double giant dipole resonance ~DGDR!. The complete energy-weighted sum of strengths ~EWSS! for the DGDR and a possible deviation from its value in the harmonic oscillators’ limit are derived for the first time with the full nuclear Hamiltonian taken into account. The numerical calculations within a schematic model show an example where this deviation turns to a strong enhancement of the EWSS for the DGDR at various particle numbers. @S0556-2813~97!00509-8# The recent observation of the double giant dipole ~DGDR! in relativistic heavy-ion reactions of a wide range of nuclei @1‐6# has attracted considerable attention. The observed excitation energy of the DGDR is about twice as much compared to the energy of the giant dipole resonance ~GDR!. Its width is larger than the GDR width by 1.6 times @1,2,5,6#. While these parameters of the DGDR are in a good agreement with the representation of the multiphonon giant resonance, which is formed by noninteracting harmonic oscillators ~phonons!, the most striking point is that its strength has been found to be strongly enhanced as compared to any theoretical estimations available so far @7‐10#. Recently, making use of a sum rule approach, Kurasawa and Suzuki @11# have demonstrated that, if the mean energy of the DGDR is twice as much compared to the GDR energy, the DGDR strength is 2 times square of that of the GDR. Thus, there is a discrepancy between the strength of the DGDR determined by the sum rules and the experimental data. In the previous work @12#, taking into account the multiphonon structure of the wave function of the GDR and DGDR, we have shown that there is a possibility for the enhancement of the E1 decay as well as excitation of the DGDR in a two-step process. The aim of the present paper is to study the deviation of the DGDR sum rule from the value, defined in the harmonic oscillators’ ~independent phonons! limit, when the full multiphonon structure of the nuclear Hamiltonian is adequately included. It is our hope that this effort will serve as a further step in improving our present understanding of the quenching of the DGDR strength in theoretical calculations as compared to the experimental systematics.

An approach is proposed for studying the spreading properties of the Gamow-Teller resonance (GTR) in heavy nuclei including the coupling to 2 p 2 h configurations and the ground-state correlations beyond RPA. The GTR is generated by a proton p -neutron h ( πp - νh ) phonon within the renormalized RPA. The second-order configuration mixing beyond RPA is realized by constructing two-phonon configurations, in which one of two intermediate phonon states is a πp - νh phonon. The numerical calculations are performed in the parent nuclei 90 Zr and 208 Pb making use of M3Y nucleon-nucleon interaction and the single-particle wave functions obtained in the standard harmonic oscillator potential. The single-particle energies around the Fermi surface are substituted with the empirical values or those given by a Woods-Saxon potential. The results obtained provide a reasonable account for recent experimental findings on the GTR in these nuclei. The extension of the present approach to highly excited (hot) nuclei is also provided. The GTR is found to be stable against temperatures up to T = 6 MeV.

The configuration of a PIB source was studied to grow uniform large-area HTS (high-temperature superconducting) films for application to coil or tape fabrication. The uniformity of thin films was simulated in cases where a PIB source was placed with tilted (Θ) and off-axis ( L ) orientation on the assumption that the thickness distribution of PIB deposited films followed the (cos α) n law. The tilted and off-axis orientation was found to improve the uniformity of the thin films. The calculated uniformity at D = 430, Θ = 30° and L = 30 was greater than 90%, where D was the source-substrate distance. Fabrication of HTS films at D = 430 reduced the source consumption and prolonged the source life significantly. As-deposited films prepared on a 6 in. rotating sample holder at D = 430 have a composition variation of no more than ±5% and a zero resistance temperature of 78–80 K.

A computational model of the glucagon/insulin-driven liver glucohomeostasis function, focusing on the buffering of glucose into glycogen, has been developed. The model exemplifies an ‘engineering’ approach to modelling in systems biology, and was produced by linking together seven component models of separate aspects of the physiology. The component models use a variety of modelling paradigms and degrees of simplification. Model parameters were determined by an iterative hybrid of fitting to high-scale physiological data, and determination from small-scale in vitro experiments or molecular biological techniques. The component models were not originally designed for inclusion within such a composite model, but were integrated, with modification, using our published modelling software and computational frameworks. This approach facilitates the development of large and complex composite models, although, inevitably, some compromises must be made when composing the individual models. Composite models of this form have not previously been demonstrated.

We study the collective response as function of excitation for a typical isoscalar mode. We apply a quasi-static picture in which the effective coupling constant changes with temperature T . Around T =2 MeV we find a marked transition in the behaviour of the strength function. Whereas at small T there appear several moderately broad peaks, the strength becomes concentrated in one low frequency mode at large T . The latter is strongly overdamped and its inertia is the one of irrotational flow.

Dissociation cross sections are calculated for the reaction 11 Li + Target → 9 Li + X within the Glauber approximation. The present Glauber calculation well reproduces experimental cross sections: the nuclear dissociation cross section has a target-mass dependence quite similar to the one obtained by Kobayashi et al. based on the factorization model and the Coulomb dissociation cross section has a target-charge dependence of Z 1.74 , close to the experimentally deduced one. The suppression of the Coulomb dissociation cross section, compared with the normal Z 2 dependence, comes from the effect of finite q ⊥ , the transverse component of momentum transfer.

We have found the root of the pseudo-spin symmetry to the Dirac equation. We found two kinds of conditions for the pseudo-spin approximation both for the case of the spherical potential and for the deformed potential.

Mathematical and computational modelling are research areas with increasing importance in the study of behaviour in complex biological systems. With the increasing breadth and depth of models under consideration, a disciplined approach to managing the diverse data associated with these models is needed. Of particular importance is the issue of provenance, where a model result is linked to information about the generating model, the parameters used in that model and the papers and experiments that were used to derive those parameters. This paper presents an architecture to manage this information along with accompanying tool support and examples of the management system in use at various points in the development of a large model.

Residual volume error influences percent body fat estimated by hydrostatic. The aim of this study was to examine the differences and relationships between the residual volumes measured on land and in water and calculated from estimate equations developed in previous studies.20 males and 20 females, aged 18-25 years, participated in this study.the residual volumes on land and in water without submerging their head were measured twice in each setting. In addition, the residual volume was calculated from 6 estimate equations developed in previous studies.Residual volumes measured on land and in water have very good trial-to-trial reliabilities (intraclass correlation coefficients:0.98), and high relationships, and did not show a significant difference. It is inferred that their difference is approximately 500 mL, being larger than trial-to-trial error. If we attach great importance to practicability rather than the above error, the residual volume on land can be used. There were no significant differences between measured volumes and those estimated by equation 5 in males and all equations except equation 6 in females. The relationships between measured and estimated residual volumes were poor in males except for equation 4, but were fair in females. Trial-to-trial reliability of residual volumes measured on land and in water is very good, and they have insignificant differences and high relationships.Of 6 estimate equations, equation 4 calculated from vital capacity has high accuracy in both sexes.

The purpose of this study was to compare the exertion and electromyography (EMG) properties during the developmental phase (DFmax) in static explosive grip (SEG), rapid submaximal exertion grip, namely fake SEG exertion (FAKE), and SEG in a muscle fatigue state.Thirty healthy males and females performed the SEG and FAKE exertions (50% and 75% of peak value as a target value). Then, they performed sustained repeated rhythmic grip for 6 min (30 times x min(-1)), and SEG after 1-min, 4-min, and 7-min (SEG after the exertion). EMG was measured concurrently to compare with the muscle activation property during each grip exertion. Eight force-time parameters evaluating the DFmax in addition to the peak value were selected.The peak value significantly decreased, and the mean power spectrum density shifted to the low-wave in SEG after the exertion as compared with before. Therefore, SEG after the exertion was judged to be a muscle fatigue state. In addition, because the frequency properties in each exertion differed, the muscle activation properties during their DFmaxs were considered to differ. From the comparison between SEG before and after the exertion and FAKE, it is suggested that the time of reaching the peak value and the relative muscle strength when reaching an inflection point are not useful as parameters to evaluate the explosive muscle function during SEG.The maximal increasing volume during the DFmax and integrated area until 0.25 and 0.5 s could discriminate a difference of the DFmaxs according to each exertion and they are useful parameters.

We investigated the effects of the iron regulatory peptide hepcidin on iron transport by the human intestinal epithelial Caco-2 cell line. Caco-2 cells were exposed to hepcidin for 24 hours prior to the measurement of both iron transport and transporter protein and mRNA expression. Incubation with hepcidin significantly decreased apical iron uptake by Caco-2 cells. This was accompanied by a decrease in both the protein and the mRNA expression of the iron-response element containing variant of the divalent metal transporter (DMT1[+IRE]). In contrast, iron efflux and iron-regulated gene1 (IREG1) expression were unaffected by hepcidin. Hepcidin interacts directly with a model intestinal epithelium. The primary effect of this regulatory peptide is to modulate the apical membrane uptake machinery, thereby controlling the amount of iron absorbed from the diet. (Blood. 2004;104:2178-2180)

Multi‐modal fission of the uranium nucleus at the low excitation energy has been dynamically investigated. The multi‐dimensional Langevin equation is used for the dynamical calculation. We used the potential energy taking account of the microscopic energy which depends on the excitation energy. We obtained the peaks of the mass distribution and the total kinetic energy (TKE) distribution. The former is consistent with experimental results and the latter is consistent with experimental systematics. We study the evolution of the mass‐asymmetry of the fragments in the dynamical process from the second saddle to the scission.

The purpose of this study was to examine the reliability and gender differences of static explosive grip (SEG) parameters based on force-time curves.data were collected from 2 trials of SEG tests on the same day and 2 trials 1 week later.50 healthy young males (21.2+/-1.57 yrs) and females (20.1+/-1.18 yrs) participated in this study.12 variables based on factors such as time-course of force, average force, integrated area, maximal rate of force development, the product of force and inclination and exponential function of force development (EXP-M) were selected as force-time parameters in SEG testing.A significant reliability was obtained for all force-time parameters except the time to 90% of maximal grip strength (MAX), with the reliability of integrated area, average force, maximal rate of force development (DFmax), and the product of force and inclination being particularly high (ICC=0.633-0.930 for the same day, ICC=0.612-0.828 for different days). There were gender differences for all parameters except the time to MAX and EXP-M (p0.05). In addition, many of the correlation coefficients between parameters were high, particularly for males. The average force, integrated area for 1 sec, and the product of force and inclination during the developmental phase significantly correlated with MAX in both males and females. The ratio between males and females in these force-time parameters was smaller than that of MAX (71.3%).It is considered that these parameters are dependent on the speed of muscle contraction. These results suggest that the evaluation parameters, such as average force, integrated area, the product of force and inclination, and maximal rate of force development are useful for evaluating static explosive grip.

A novel electron beam system for large-area patterning of printed wiring boards (PWBs) has been developed. The system features a large field deflection, high-scanning speed, and stably focused beam in the large field. In order to deflect electron beams in a large area with high precision, particular attention was paid to the construction of a deflection data correction system. Various errors originating from the optics are measured, and the data to correct for these errors are calculated and stored prior to imaging. These data are output to the optics column at a rate of up to 10 MHz during imaging. In addition, sensors provide the data to correct the position error originating from the height variations and warp of the PWB for each field. It is confirmed that the beam position precision is +or-12 mu m for a field of 52 mm*52 mm. >

There is a possibility that heat stimulus by linear polarized near-infrared light irradiation (PL: Super Lizer HA-30, Tokyo Medical Laboratory) improves the range of joint motion, because the flexibility of soft-part tissues, such as a muscle or a tendon, is improved by increasing the muscle temperature. The purpose of this study was to examine the influence of PL-irradiation on the ranges of shoulder and ankle motions.30 healthy young adults (15 males: mean+/-SD, age 19.1+/-0.8 yrs, height 173.3+/-4.6 cm, body mass 68.5+/-8.0 kg and 15 females: mean+/-SD, age 19.2+/-0.7 yrs, height 162.3+/-4.5 cm, body mass 58.1+/-6.6 kg) participated in the experiment under PL-irradiation and no-irradiation (placebo) conditions.the angles of shoulder and ankle joint motions were measured twice, before and after the PL- and placebo-irradiations. The angle of a motion was defined as the angle connecting 3 points at linearity as follows: for the shoulder, the greater trochanter, acromion, and caput ulnare, and for the ankle, the knee joint, fassa of lateral malleolus and metacarpal bone. Each angle was measured when a subject extended or flexed maximally without support.The trial-to-trial reliability of each range of joint motion was very high. All parameters in PL-irradiation were significantly larger in postirradiation than pre-irradiation, and the value of postirradiation in PL-irradiation was significantly greater than that for placebo. The ranges of shoulder and ankle motions in placebo-irradiation were also significantly greater in postirradiation than pre-irradiation. Moreover, the change rate for each range of joint motion between pre- and postirradiations was significantly greater in PL-irradiation in both joints. In PL-irradiation, most subject's motions were greater in postirradiation than pre-irradiation, but not in the placebo-irradiation. The effect of PL-irradiation tended to be greater on subjects with a small range of a joint motion.It is considered from the present results that the ranges of shoulder and ankle motions became greater with PL-irradiation, and is effective as a warming-up method.

Intramolecular electrostatic repulsions between the local negative charge on a trifluoromethyl group and that on the ortho position of an aryl moiety of a nucleophile was found to be a controlling factor of the diastereoselectivity in a cyclopropanation reaction, in which the electrostatic repulsion was evaluated quantitatively.

The purpose of this study was to clarify the influence of change of total body water caused by exercise and drinking, on relative body fat (%BF) based on three bioelectrical impedance analyses (BIA) methods, between hand and foot (H-F), between hand and hand (H-H), and between foot and foot (F-F).The subjects were 30 Japanese healthy young adults aged 18 to 23 years (15 males, 15 females). Measurements were made three times for each BIA method; before and after exercise with sweat, and after drinking, and also twice according to the under water weighing (UW) method, before exercise and after drinking. A pedaling exercise, with a bicycle ergometer, was used for 60 minutes as the exercise.The relationship of %BF between the UW method and each BIA method was mid-range or more (r=0.765-0.839). However, %BF based on the H-F and F-F BIA methods were higher than that based on the UW method. After drinking, %BF of all the BIA methods were higher than the UW method. %BF of the BIA methods after exercise indicated values lower than those before exercise. %BF of the H-F and H-H BIA methods after drinking were a little higher than those before exercise, indicating that those measurements reflect a slight change of body water.It was demonstrated that %BF of any BIA method reflect the change of body water caused by exercise, sweating, and drinking.

A divalent metal transporter, DMT1, located on the apical membrane of intestinal enterocytes is the major pathway for the absorption of dietary non-haem iron. Using human intestinal Caco-2 TC7 cells, we have shown that iron uptake and DMT1 protein in the plasma membrane were significantly decreased by exposure to high iron for 24 h, in a concentration-dependent manner, whereas whole cell DMT1 protein abundance was unaltered. This suggests that part of the response to high iron involved redistribution of DMT1 between the cytosol and cell membrane. These events preceded changes in DMT1 mRNA, which was only decreased following 72 h exposure to high iron.

We report a patient with chronic myelogenous leukemia who received a second transplant from a one-locus HLA-mismatched unrelated donor after rejection of an initial bone marrow graft. For the first transplant, HLAs were fully matched, conditioning with busulfan + cyclophosphamide (CY) was applied, and cyclosporin A + short-term methotrexate (sMTX) was used for prophylaxis against GVHD. A complete chimera was not obtained, and the graft was rejected on day 122. For the second transplant, there was a one-HLA locus (DR) mismatch, conditioning was done with total body irradiation + cytarabine + CY, and GVHD prophylaxis consisted of FK506 + sMTX. Engraftment was obtained on day 27, and no graft failure was occurred at the time of writing. This case suggests that strong immunosuppression may have prevented rejection of the second bone marrow graft.

The purpose of this study was to establish a convenient prediction equation for residual volume for Japanese male and female young adults after comparisons in reliability and validity with previous equations widely used in studies of body composition with Japanese subjects.The subjects were healthy Japanese, 110 males aged 18 to 27 years and 82 females aged 18 to 22 years. Measured residual volume (MRV) was measured with a nitrogen washout technique and each predicted residual volume (PRV) was predicted using a prediction equation. Multiple regression analysis on all possible selections was applied to determine a suitable and convenient prediction equation for residual volume.Intra-class correlation coefficient and a coefficient of Cronbach in MRV exceeded 0.9, indicating high reliability. Pearson s correlation coefficients between MRV and each PRV for males and females ranged from 0.225 to 0.327 and - 0.485 to 0.507, respectively. Multiple correlation coefficient adjusted for degrees of freedom applying the one variables of height was 0.592 for males and 0.670 for females.Considering the practicability of measurement, prediction equations for residual volume with height in Japanese male and female young adults have been proposed. The new prediction equations (PRVnew) are as follows: male: PRVnew= 32.16 yen height (cm) - 4113.70 (Radj= 0.592, SE= 247.13 ml); female: PRVnew = 34.03 yen height (cm) - 4407.78 (Radj= 0.670, SE= 195.74 ml).

We have examined the influence of rotation on the potential energy and the transport coefficients of the collective motion (friction and mass coefficients). For axially symmetric deformation of nucleus Th-224 we have found that at excitations corresponding to temperatures T > 1 MeV the shell correction to the liquid drop energy practically does not depend on the angular rotation. The friction and mass coefficients obtained within the linear response theory for the same nucleus at temperatures larger than T=2 MeV are rather stable with respect to rotation provided that the contributions from spurious states arising due to the violation of rotation symmetry are removed. At smaller excitations both friction and mass parameters corresponding to the elongation mode are growing functions of rotational frequency., 16 pages, 5 eps figures, Latex, submitted to Nucl.Phys.A

The conditions for the pseudospin symmetry hidden in the Dirac equation are found for the case of the deformed potential both from the large and small components of the Dirac wave function. The numerical analysis based on the relativistic mean-field theory is carried out for ${}^{154}\mathrm{Sm}.$ It is confirmed that the conditions found from the large components of the Dirac wave function are satisfied better than those from its small components. As long as these conditions are satisfied, the pseudospin symmetry appears in the amplitudes with the unnatural ${l}_{z}$ $(z$ component of orbital angular momentum) in both large and small components.

In this paper we investigate the role of single-particle energies on the low-lying states of ${}^{132}\mathrm{Ba},$ a typical O(6) nucleus in the IBM and the fermion dynamical symmetric model (FDSM). It is found that one can reproduce the physical quantities of a realistic system with nondegenerate single-particle energies using degenerate single-particle levels and a slightly different parametrization of the two-body interaction. However, if the single-particle splittings are enlarged by a factor of 1.5, the O(6)-like behavior of the nucleus is lost and a model that assumes degenerate levels cannot describe its collective structure. Contributions from interactions other than monopole and quadrupole pairing and a quadrupole-quadrupole force are found to be unimportant. Although the role of the abnormal-parity level depends on the details of the single-particle structure, its effects can be ``compensated'' by using different Hamiltonian parameters and degenerate single-particle levels in a FDSM treatment.

The validity of the SD-pair truncation of the shell model is tested in a single j shell and in many j shells within the framework of the nucleon pair shell model. It is found that the SD-pair truncation is a good approximation of the shell model in the single-j case when the Hamiltonian consists of (monopole and quadrupole) pairing plus quadrupole-quadrupole-type interaction. The SD-pair truncation deteriorates if the quadrupole-quadrupole interaction is artificially large compared with the monopole pairing interaction. For multi-j shells, schematic calculations in the degenerate sd, pf, and sdg shells are performed for the extreme case of a pure quadrupole-quadrupole interaction. There is a large difference between the binding energies in the SD-pair-truncated subspace and those calculated in the full shell model space as in the case of a single-j shell. However, it is found that the basic properties of the band structure remain intact, and that the difference in energy levels, i.e., moments of inertia, can be easily absorbed by adjusting interaction strengths without changing the transition rates.

The nucleon pair shell model calculation is performed in terms of the SD collective pairs which are obtained in a suitable way to obtain the maximum collectivity. The method is applied to even-even Sn, Te, Xe, Ba, and Ce isotopes near the $A=130$ region employing the (monopole and quadrupole) pairing plus quadrupole-quadrupole-type interaction with a very few parameters. The structure of energy levels for the quasi-\ensuremath{\gamma} band as well as the ground band is well reproduced in each nucleus. Other properties such as $E2$ transition rates and binding energies also agree with experimental data very well. The overall fit with the experimental data is superior to the previous calculations.

The formalism for the nucleon-pair approximation of the shell model (NPSM) is greatly simplified by applying the Wick theorem for the coupled cluster in a more sagacious way. Using a new coupling scheme of the basis, the new formalism not only unifies the analytic expressions of the Hamiltonian matrix elements for even and odd nuclei (odd-even or odd-odd), but more importantly reduces the computing time drastically, which is crucial for the NPSM calculations of odd nuclei to be realizable.

Isoscalar monopole density vibrations in spherical nuclei with a sharp surface are studied in a nonlinear hydrodynamical approach. The frequency shift of the one- and two-phonon excitations due to nonlinear terms is obtained. The frequencies of one- ~two-! phonon giant isoscalar monopole resonances calculated in the nonlinear hydrodynamic theory increase by ’2%(8%) in heavy nuclei and by ’14‐18 % ~50%! in light nuclei compared to the linear approximation. The frequency shift is a function of both the mass number A and the parameters of the nucleon-nucleon interaction.

A 22-year-old woman was admitted with purpura. Acute promyelocytic leukemia (APL) with disseminated intravascular coagulation (DIC) was diagnosed. On the 17th day after treatment with all-trans retinoic acid (ATRA), left subdural hematoma developed. Although coagulation abnormalities were still observed, emergency surgery was performed. Acute epidural hematoma was confirmed by computed tomographic scan after the operation. A second operation for drainage was successful. Post-operative intracranial hematoma may be caused by rapid decompression induced by surgery, but DIC could also be involved. This case underscored the need for careful consideration of the indications for surgical treatment of such DIC patients, with close follow-up monitoring for the postoperative development of neurological symptoms.

Frontotemporal dementia (FTD) is a dementia syndrome characterized by peculiar behavioral changes arising from frontotemporal involvement and distinct from Alzheimer's disease (AD). The purpose of this study was to elucidate the specific patterns in cerebral glucose metabolism in patients with FTD and to compare them with the patterns in patients with AD and normal elderly subjects using fluorodeoxyglucose (FDG) and PET.Twenty-one patients with a clinical diagnosis of FTD [mean age 67.0 +/- 7.0 yr, Mini Mental State Examination (MMSE) score 18.7 +/- 5.7], 21 age-, sex- and dementia-severity-matched patients with probable AD (mean age 66.9 +/- 7.1 yr, MMSE score 20.2 +/- 5.5) and 21 age- and sex-matched normal control subjects (mean age 66.8 +/- 5.7 yr) were studied. The cerebral metabolic rate for glucose (CMRglc) was measured with FDG and PET. Absolute measures of regional CMRglc were compared among the three groups. One-way ANOVA and the posthoc Tukey HSD test were used for statistical analyses.In the FTD group, CMRglc was preserved only in the left cerebellum, right sensorimotor area and occipital lobes. The CMRglc was significantly lower in the FTD group as opposed to the AD group in the hippocampi, orbital gyri, anterior temporal lobes, anterior cingulate gyri, basal ganglia, thalami, middle and superior frontal gyri and left inferior frontal gyrus.Although metabolic abnormality in FTD is predominant in the frontal and anterior temporal lobes and the subcortical structures, it is more widespread than has been previously stressed. These findings document an FTD-specific cerebral involvement and facilitate differential diagnosis of degenerative dementias.

The purpose of this study was to clarify the changes in hippocampal perfusion in mild-to-moderate Alzheimer's disease using PET and (15)O-labeled water.Sixteen patients with probable mild-to-moderate Alzheimer's disease (age: 68.1+/-11.3 yr; MMSE: 21.1+/-4.5) and 10 normal volunteers (age: 65.1+/-8.2 yr) were studied. Regional cerebral blood flow (CBF) and cerebral blood volume (CBV) were measured using (15)O-labeled water autoradiographic method, C(15)O-gas inhalation technique and PET.Although the mean CBF in the parietotemporal region was significantly lower in the patient group than in the control group, the mean CBF in the hippocampus did not show significant reduction between the two groups, both in absolute and relative values. There was no significant regional CBV difference between the two groups. Parietotemporal perfusion correlated well with cognitive scores, both in absolute and relative values, in Alzheimer's disease, but hippocampal perfusion did not correlate well.Hippocampal perfusion was preserved in mild-to-moderate Alzheimer's disease.

We measured γ-ray multiplicity and light charged particle (LCP) multiplicity simultaneously in coincidence with binary decay fragments in the reactions of 84Kr (10.6 and 8.5 MeV/nucleon)+27Al and 58Ni (10.0 MeV/nucleon)+56Fe. We observed the prescission time and charge distribution of heavy fragments as a function of the angular momentum of the system applying the measured γ-ray multiplicity as an angular momentum filter. The deduced prescission time becomes smaller as the angular momentum of the system increases. For 84Kr+27Al, the fusion-fission reaction seems to occur dominantly only at the angular momentum ∼70 ℏ, which is concluded from the dependence of prescission proton multiplicity on the total kinetic energy (TKE). The charge distribution of binary decay fragments changes from the symmetric mass division to asymmetric one with increasing the γ-ray multiplicity.

Based on the Relativistic continuum Hartree-Bogoliubov (RCHB) theory, the pseudo-spin approximation in exotic nuclei is investigated in Zr and Sn isotopes from the proton drip line to the neutron drip line. The quality of the pseudo-spin approximation is shown to be connected with the competition between the centrifugal barrier (CB) and the pseudo-spin orbital potential (PSOP). The PSOP depends on the derivative of the difference between the scalar and vector potentials $dV/dr$. If $dV/dr = 0$, the pseudo-spin symmetry is exact. The pseudo-spin symmetry is found to be a good approximation for normal nuclei and to become much better for exotic nuclei with highly diffuse potential, which have $dV/dr \sim 0$. The energy splitting of the pseudo-spin partners is smaller for orbitals near the Fermi surface (even in the continuum) than the deeply bound orbitals. The lower components of the Dirac wave functions for the pseudo-spin partners are very similar and almost equal in magnitude., Comment: 22 pages, 9figures

A 75-year-old man presented with palpitations due to atrial flutter. Transthoracic echocardiography revealed a mobile aortic valve mass (17 mm in diameter) attached to the non-coronary cusp of the aortic valve. There was no evidence of hypercoagulative state. Computed tomography showed old cerebral infarction in the territory supplied by the right middle cerebral artery. The mass was surgically resected. The aortic valve was preserved because there were no organic changes in the valve. Histological examination demonstrated an organized thrombus. Only three cases of thrombus attached to the normal native aortic valve have been reported. Native aortic valve thrombus may be important in the differential diagnosis of aortic valve mass.

We studied changes in cerebral perfusion and oxygen metabolism to elucidate the pathophysiological nature and clinical significance of white matter hyperintensities in Alzheimer's disease (AD).Sixteen AD patients (age 71.6 +/- 3.1 yr) whose T2-weighted MR images showed white matter hyperintensities, and 16 age-matched AD patients (age 71.0 +/- 4.3 yr) without white matter hyperintensities were compared. Regional cerebral blood flow (CBF), oxygen metabolism (CMRO2) and oxygen extraction fraction (OEF) were measured by using (15)O steady-state method and PET.There was no significant difference in cognitive impairment between the two groups. Compared to the patients without white matter hyperintensities, those with them had significantly low CBF values and significantly high OEF values in all cortical and white matter regions. However, there were no significant differences in CMRO2 values between the two groups. Severity of white matter hyperintensities correlated with the mean cortical and mean white matter OEF.In AD patients, white matter hyperintensities on T2-weighted MR images represent ischemic changes in which oxygen metabolism and function are fairly compensated. These changes are not disease-specific but are age-associated coincidences, as in normal aging with or without vascular risk factors.

Although regional cerebral metabolism and blood flow in Alzheimer's disease (AD) have been studied extensively with PET and SPECT, few reports have been concerned with cerebellar metabolism or perfusion in Alzheimer's disease. To evaluate cerebellar glucose metabolism in Alzheimer's disease patients, we studied the cerebellar and cerebral metabolic rate for glucose (CMRglc) using 2[18F]fluoro-2-deoxy-D-glucose (18F-FDG) and PET.Sixty-eight patients with Alzheimer's disease and 13 age-matched normal control subjects were examined. According to scores obtained on the Mini-Mental State Examination (MMSE), Alzheimer's disease patients were classified into three groups: severe (n = 9), moderate (n = 33) and mild (n = 26).The cerebellar glucose metabolism in the severe Alzheimer's disease group was significantly lower (cerebellar glucose metabolism: 5.71 +/- 0.62 mg/100 g/min) than that of the control group (6.85 +/- 0.66 mg/100 g/min), while temporal and parietal CMRglc were much more decreased. The cerebellar glucose metabolism in the mild and moderate Alzheimer's disease groups also showed lower levels than that of the control group, but the differences did not reach significant levels. Like other cortical CMRglc, the cerebellar glucose metabolism correlated with cognitive impairments.In severe Alzheimer's disease, cerebellar glucose metabolism is significantly reduced. The method of analysis using normalization of regional metabolic data to cerebellar values may be liable to err in severe Alzheimer's disease patients.

PURPOSE: To determine the diagnostic potential of MR imaging to show white matter involvement in frontotemporal dementia. METHODS: We evaluated MR signal intensity in cerebral white matter by visually inspecting and by quantitatively measuring signal intensity on MR images in 22 patients with frontotemporal dementia. The findings were compared with those in 22 age- and sex-matched patients who had had Alzheimer disease for the same length of time and with 16 age- and sex-matched healthy control subjects. RESULTS: Patients with frontotemporal dementia had a significant increase in white matter signal intensity in the frontal and/or temporal lobes on T2- and proton density-weighted images. Visual inspection of regular proton density-weighted images and measurements made on the T2- and proton density-weighted images were sensitive to changes in white matter signal. CONCLUSION: Increased MR signal intensity in the frontotemporal white matter on T2- and proton density-weighted MR images is a useful diagnostic sign of frontotemporal dementia and distinguishes this condition from Alzheimer disease.

Previous computations of the potential landscape with the shapes parameterized in terms of Cassini ovaloids are extended to collective dynamics at finite excitations. Taking fission as the most demanding example of large scale collective motion, transport coefficients are evaluated along a fission path. We concentrate on those for average motion, namely stiffness C, friction \gamma and inertia M. Their expressions are formulated within a locally harmonic approximation and the help of linear response theory. Different approximations are examined and comparisons are made both with previous studies, which involved different descriptions of single particle dynamics, as well as with macroscopic models. Special attention is paid to an appropriate definition of the deformation of the nuclear density and its relation to that of the single particle potential. For temperatures above 3 MeV the inertia agrees with that of irrotational flow to less than a factor of two, but shows larger deviations below, in particular in its dependence on the shape. Also friction exhibits large fluctuations along the fission path for small excitations. They get smoothed out above 3 - 4 MeV where \gamma attains values in the range of the wall formula. For T > (or=) 2 MeV the inverse relaxation time \beta = \gamma /M turns out to be rather insensitive to the shape and increases with T., Comment: 30 pages, Latex, 15 Postscript figures; to appear in PRC; e-mail: hhofmann@physik.tu-muenchen.de www home page: http://www.physik.tu-muenchen.de/tumphy/e/T36/hofmann.html

The wishes of patients with terminal cancer are often not realized even if they indicate they want to die at home. We introduced a 24-hour visiting care system from November, 1994, with a view to making it possible for the patient who wants to to stay at home. As a result, the rate of the death at home increased; thus, the 24-hour visiting care system was significant for terminal care at home. On the other hand, from the viewpoint of a medical institution, the lack of sufficient cooperation with doctors and the increase of the burden on the staff were pointed out as problems to be resolved.

We sought to determine if there are regional differences in cerebral blood flow (CBF) and cerebral metabolic ratio for oxygen (CMRO2) in normal subjects during the resting state.Regional CBF, CMRO2 and oxygen extraction fraction (OEF) in 15 normal volunteers (mean age 58.8 +/- 8.2 yr) were measured during rest using PET and a 15O-gas steady-state technique.CBF and CMRO2 in the visual cortex were significantly higher than those in other cortices. Additionally, OEF in the sensorimotor cortex was significantly lower than that in other cortical regions.CBF and CMRO2 in the visual cortex are always high, and low OEF in the sensorimotor cortex exists even in resting state in normal subjects. We hypothesize that these regional functional differences would result in different resistances to degeneration.