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The synthesis of dendrimer-like star-branched poly(methyl methacrylate)s (PMMAs) were carried out by an iterative divergent approach which involved a coupling reaction of α-functionalized living PMMA with two tert-butyldimethylsilyloxymethylphenyl (SMP) groups with benzyl bromide (BnBr) chain-end-functionalized PMMA and a transformation reaction of the introduced SMP groups into BnBr functionalities. The dendrimer-like star-branched PMMAs up to the seventh generation have been successfully synthesized by repeating these two reactions seven times. The resulting polymers all were well-defined in branched architecture, precisely controlled in chain length and degree of end-functionality, and extremely narrow in molecular weight distribution (Mw/Mn < 1.03). The seventh-generation PMMA herein synthesized was 1.97 × 106 in Mw value and consisted of 508 PMMA segments. Furthermore, the 512 SMP termini were presented along its periphery. Viscosity measurement indicates that the dendrimer-like star-branched polymer...

JTP-59557 [(-)-4-(2-tert-Butyl-4,5-dichlorophenyl)-5-(5-trifluoromethylpyridin-2-ylsulfanyl)-4H-[1,2,4]triazol-3-ol] showed an inhibitory effect on Na(+)-dependent inorganic phosphate (Pi) transport in intestinal brush border membrane vesicles with an IC(50) value of 0.40 microM in rabbit and with an IC(50) of 0.19 microM in rat, without affecting Na(+)-independent Pi and Na(+)-dependent d-glucose transport activities. In Chinese hamster ovary (CHO) cells expressing human type IIb Na/Pi cotransporter (type IIb), JTP-59557 decreased human type IIb-mediated Pi uptake with an IC(50) of 0.12 microM. In rabbit intestinal brush border membrane vesicles, JTP-59557 behaved as a noncompetitive inhibitor with respect to Pi. In an in vivo study, single administration of JTP-59557 significantly decreased the intestinal Pi absorption rate, when either Pi solution or laboratory chow was given to rats. In this report, we show that JTP-59557 is a potent, selective, stereospecific, noncompetitive inhibitor of intestinal Na/Pi cotransporters including type IIb, and it may represent a new class of intestinal Pi absorption inhibitor.

The crystal structure of isostructural SrCuV(2)O(7) and BaCuV(2)O(7) consists of one-dimensional (1D) zigzag chains of Cu atoms with next-nearest-neighbor interaction. The main intrachain interaction was found to be ferromagnetic and estimated at 4.6 K (Hamiltonian H approximately -2J). SrCuV(2)O(7) and BaCuV(2)O(7) are new examples in the scanty family of 1D ferromagnets. Isothermal magnetization measurements at 0.08 K and specific heat data showed that MCuV(2)O(7) exhibits antiferromagnetic long-range ordering at T(N) = 1.36 K for SrCuV(2)O(7) and T(N) = 1.47 K for BaCuV(2)O(7). Spin-flop transitions were observed in the antiferromagnetic state at 0.08 K near 0.5 kOe in SrCuV(2)O(7) and 2 kOe in BaCuV(2)O(7). In air, SrCuV(2)O(7) and BaCuV(2)O(7) melted incongruently above 983 and 1018 K, respectively.

Magnetic properties of S = 1 / 2 linear trimer cluster compounds A3Cu3(PO4)4 (A=Ca, Sr, and Pb) were investigated. Magnetic susceptibility data for the three compounds showed that paramagnetic copper spins form trimers with the total spin of 1/2 below about 45 K. Specific heat and magnetization measurements indicated that the trimer clusters undergo ferromagnetic long-range ordering at T C = 0.91 K for A=Ca and antiferromagnetic long-range ordering at T N = 0.91 K for A=Sr and T N = 1.26 K for A=Pb. A3Cu3(PO4)4 exhibited 1/3-magnetization plateau at least up to magnetic field of 55 T at 1.3 and 4.2 K. A3Cu3(PO4)4 with A=Sr and Pb showed a spin-flop transition near 0.03 T in the antiferromagnetic state at 0.08 K. Specific heat data at magnetic fields clearly showed broad maxima at low temperatures due to the finite intra-chain interaction in one-dimensional arrays of the trimers.

The magnetic properties of O2 adsorbed in nanochannels of porous metal-organic solids CPL-1 and CPL-p1 have been investigated by means of high-field magnetization process measurement. The contribution from adsorbed O2 shows the metamagnetic-like behavior in both compounds. We propose “the field-induced rearrangement mechanism” as the explanation for the metamagnetic-like behavior. It is known for the O2-O2 dimer that the magnetic interaction depends strongly on the intermolecular distance and the orientation of molecular axes. It is considered naturally that the stable arrangement with saturated magnetic moment in the sufficient high field is different from the H-structure which is stable at zero field.

Azurite (Cu 3 (CO 3 ) 2 (OH) 2 ) is a model substance of a diamond spin chain, one of frustrated antiferromagnetic quantum spin chains. The high field magnetization up to 60 T, magnetic susceptibility, magnetic entropy, muon spin relaxation and 1 H-NMR of azurite have been measured using single crystals. A distinct 1/3 magnetization plateau is confirmed to be present in the magnetization curve. Two resonance peaks of 1 H-NMR. were observed. By analyzing temperature dependencies of their hyperfine shift. we found two different local susceptibilities which correspond to susceptibility of dimer and monomer spins, respectively. New field induced phase transition was found to occur at a critical field where the magnetic plateau onsets. A short range magnetic ordering developed in a peculiar two-stage process, which was revealed by temperature dependence of the magnetic specific heat and susceptibility.

We measured the magnetization processes of the S = 1/2 antiferromagnetic chain compound, Cu benzoate. From the inelastic neutron scattering and the specific heat measurements it was recently discovered that the substance exhibits an unexpected gap which varies approximately as the 2/3 power of an applied magnetic field. The primary mechanism of the gap formation is produced by an effective staggered field due to both the alternating g-tensor and the Dzyaloshinskii-Moriya interaction. We observed the effect of the effective staggered field on the magnetization process of Cu benzoate as a rounding behavior near the saturation field as well as an initial nonlinear increment near zero field. The experimental results are well reproduced by the numerical calculation on the Hamiltonian which includes the appropriate term of the staggered field, using the finite temperature density matrix renormalization group method.

This review presents the precise syntheses of a variety of new chain-end- and in-chain-multi-functionalized polymers, regular and asymmetric star-branched polymers, star-linear block polymers, densely branched and graft copolymers carrying two branches in each repeating unit, and dendritic hyperbranched and star-branched polymers. These specialty polymers in terms of function and branched architecture are synthesized by recently developed methods using functionalized 1,1-diphenylethylene derivatives in conjunction with living anionic polymers based on the ‘iterative’ concept. In iterative methods, the reaction sites are regenerated after each iterative reaction sequence, and the same reactions may be repeated to afford successively and, in principle unlimitedly, the objective polymers until a steric limitation is encountered. Indeed, the above-mentioned polymers have been successively synthesized by the iterative methods. The scope, limitations, and possibilities for iterative methods will be discussed.

Dynamics of the relativistic flow in pair plasmas with force-free magnetic configuration is investigated by using a three-dimensional fully relativistic electromagnetic particle-in-cell code. This study is an extension of the work by Haruki and Sakai [Phys. Plasmas 8, 1538 (2001)] that was done in a two-dimensional force-free magnetic configuration. They found that during the early stage of the interaction there occurs the streaming instability, which induces the electromagnetic perturbations associated with generation of quasi-static magnetic field. In the nonlinear stage the force-free magnetic field becomes unstable against the firehose instability and then magnetic islands are formed through magnetic reconnection. The dissipated magnetic field energy is converted to the plasma heating as well as the high-energy particle production. It is found that the three-dimensional configuration could result in completely different dynamics, except for the initial phase where the streaming instability develops. I...

In the context of quantum spin dynamics of a two-level system, we study the dynamic magnetization process of dimerized Mn2+-Mn2+ pairs in the diluted antiferromagnet RbMncMg1-cF3. Measurements have been performed up to 55 T and lower temperature down to 0.1 K . Magnetization anomalies are associated with successive large and small magnetization steps at specific fields with regular interval. Main steps occur at equally spaced level-crossing fields Bn (1⩽n⩽5) with a separation of Δ B=6.4 T and subsidiary ones are classified into higher harmonics which fall just in between at the fields B n/2 (1⩽n⩽10) separated by Δ B/2,B n/3 (1⩽n⩽15) separated by Δ B/3,B n/4 (1⩽n⩽20) separated by ΔB/4 and so on when the energy levels have separation with a simple ratio such as (1:1), (1:2), (1:3) and so on. At the lowest temperature, the observed dM/dB curve becomes simpler, suggesting important roles of low-lying excited levels, together with a spin-phonon coupling and a phonon bottleneck effect.

The first-, second-, and third-generation dendrimer-like branched poly(methyl methacrylate)s (PMMA)s were synthesized by an iterative divergent approach which involves a coupling reaction of α-functionalized living anionic PMMA with chain-end-functionalized PMMA with benzyl bromide moieties and a transformation reaction of the tert-butyldimethylsilyloxymethylpheny groups into benzyl bromide functionalities. The iterative reaction sequence could be repeated three times without problem to afford a series of three generations dendrimer-like branched PMMAs with well-defined architectures and precisely controlled chain lengths. Moreover, an amphiphilic dendrimer-like branched block copolymer was synthesized successfully in a similar manner by using the living anionic polymer of the protected 2-hydroxyethyl methacrylate (HEMA) instead of living anionic PMMA at the final reaction stage. The resulting polymer was made of the inner 1, 4, and 8 PMMA segments and the outer 16 poly(HEMA) segments. The solution behavi...

At 4.2 K, the coercive field of Ni film on GaAs (0 0 1) was five times larger than that of Ni/Si (0 0 1). Because of these findings, a multilayer, Ni/Si/Ni/GaAs was prepared and its magnetization process was studied in a temperature range from 1.8 to 360 K. At temperatures below 250 K, an antiparallel spin state was observed, and this became the strongest at the lowest (1.8 K) temperature. The bottom Ni layer of the multilayer was observed to be totally influenced by the underneath GaAs but not by the Si.

The synthesis of well-defined chain-end-functionalized poly(methyl methacrylate)s with a definite number of benzyl bromide moieties via an iterative divergent approach starting from the living anionic polymer of methyl methacrylate is described. Only two sets of reactions involving coupling and transformation reactions are needed for the entire iterative reaction sequence. By repeating the iterative reaction sequence, chain-end-functionalized poly(methyl methacrylate)s with 2, 4, 8, and 16 benzyl bromide moieties were synthesized successfully. The resulting benzyl bromide-functionalized poly(methyl methacrylate)s underwent coupling reaction with living anionic polymers of methyl methacrylate, tert-butyl methacrylate, styrene, and isoprene to quantitatively afford well-defined regular 3-, 5-, 9-, and 17-arm star-branched poly(methyl methacrylate)s and asymmetric star-branched polymers containing poly(methyl methacrylate) segments.

Polycrystalline thin Ni films deposited onto GaAs (0 0 1) show a transition of the magnetic anisotropy depending on its thickness. The anisotropy is perpendicular to the film plane for the thicknesses of the film ⩽12 nm. This becomes in-plane in the films having thicknesses ⩾15 nm. The films are deposited onto the n-type GaAs (0 0 1) substrate by the usual thermal evaporation method and also by the electron beam evaporation in ultra high vacuum onto a GaAs epilayer in the standard molecular beam epitaxy system. The magnetization and ferromagnetic resonance (FMR) are observed in the temperature range from 4.2 to 300 K. For the discussion of the microscopic origin of the anomalous properties in magnetization and FMR experiments, the experimental results are reviewed by introducing a uniaxial anisotropy, which is calculated from the easy-axis and hard-axis magnetization data. This calculated anisotropy is able to explain the temperature and angle dependency of the FMR spectra of the Ni films. Hence the magnetization and FMR spectra are in agreement with the type of the anisotropy and its temperature dependency. In addition to these, the temperature dependence of the in-plane magnetic anisotropy is able to explain the previously reported anomalous effect of reducing the squareness at low temperatures in Ni/GaAs.

The effects of various sodium salts on the phase behavior of monoacylglycerol were investigated for fully hydrated monoelaidin systems by means of X-ray diffraction and differential scanning calorimetry. The hydrated monoelaidin systems form lamellar and bicontinuous cubic phases, depending on the temperature. Calorimetric data showed that the sign and magnitude of the phase transition temperature shifts on addition of salts are consistent with the Hofmeister series which is determined according to the efficiency of salting-out of proteins. Kosmotropic salts, having a great ability for the salting-out of proteins, increase the lamellar gel to lamellar liquid crystalline phase transition temperatures and decrease the primitive cubic to body-centered cubic (Im3m to Pn3m) phase transition temperatures. On the other hand, chaotropic salts, having a weak ability for the salting-out of proteins, exhibit the opposite effect. X-ray diffraction data demonstrated that chaotropic salts expand the lattice constants of fully hydrated monoelaidin in the Pn3m cubic phase whereas kosmotropic salts reduce the lattice constants. The above results are discussed in comparison with previous results reported for phospholipids and glycolipids. In addition, the structures of the cubic phases are discussed, based upon the above results.

The synthesis of well-defined heteroarm star-branched polymers having poly( t BMA) arms by the coupling reactions of living anionic polymers of tert -butyl methacrylate ( t BMA) with chain-functionalized polymers with a definite number of benzyl halide moieties was described. The reaction of living anionic poly( t BMA) bearing potassium countercation with benzyl bromide-functionalized polystyrenes proceeded readily and quantitatively in THF at −40 °C for 1 h and −78 °C for 5 h, respectively. Similarly heteroarm star-branched polymers of AB 2 , AB 3 , AB 4 , A 2 B 4 , and ABC 4 types with well-defined architectures were successfully synthesized. On the other hand, the same living poly( t BMA) was sluggish to react with benzyl chloride-functionalized polystyrenes, requiring 168 h to achieve quantitative formation of AB 4 star polymer. Moreover, no reaction occurred between living poly( t BMA) bearing lithium countercation in the presence of LiCl and benzyl chloride-functionalized polystyrene in THF at −78 °C for 168 h.

We have investigated the physical properties of the magnetic diluted triangular lattice antiferromagnetic system Li2Sc1-xSnxMo3O8. For all compounds, no mangetic ordering has been observed. On the other hand, the partial spin disappearing behavior is found in all Sn-substituted compounds except x = 0, which has been also observed in the similar magnetic system LiZn2Mo3O8. Considering the relationship between the crystal structure and the magnetism, the partial spin disappearance is properly explained by a formation of the valence bond glass derived from the randomness effect

Purpose The Le Fort I osteotomy (L-I) requires extensive dissection and manipulation of tissue, causing hemodynamic instability and an undesirable postoperative stress response. This study aimed to clarify the most effective dose of remifentanil during L-I. Materials and Methods This study was designed as a prospective, randomized, controlled double-blinded study. Patients (American Society of Anesthesiologists physical status I to II) undergoing L-I were randomly assigned to receive anesthesia with propofol and remifentanil under 3 remifentanil dose conditions: 0.25 μg/kg/minute (group 1), 0.5 μg/kg/minute (group 2), and 0.75 μg/kg/minute (group 3). All patients underwent L-I with propofol and remifentanil target-controlled anesthesia. The study endpoints were mean arterial pressure (MAP) and heart rate. Data were recorded before L-I (20-minute period before surgery), during L-I (from the beginning of surgery to downfracture), and after L-I (20-minute period after downfracture). Average age, gender, average body mass index, aimed maxillary position, average bispectral index, average surgery time, and average blood loss also were examined. Data were analyzed using the Bartlett test and then 1-way analysis of variance with the Bonferroni multiple comparison test. Results Data were obtained from 20 patients (9 men, 11 women). The average operating times for groups 1, 2, and 3 were 53.1, 46.7, and 49 minutes, respectively. The age range was 18 to 46 years (average, 26.05 yr). The rate of MAP increase from before to during L-I in group 1 was 10.8% (n = 7). The rate of MAP increase from before to during L-I in group 3 was 2.1% (n = 6). Group 3 showed a significantly lower rate of MAP increase during and after L-I compared with group 1 (P Conclusion Remifentanil administration at 0.75 μg/kg/minute stabilized hemodynamics during L-I without major side effects. Results indicated that the standard index of remifentanil administration during L-I should be 0.75 μg/kg/minute when using oxygen, propofol, and remifentanil for general anesthesia.

In a frustrated J_1-J_2 chain with the nearest-neighbor ferromagnetic interaction J_1 and the next-nearest-neighbor antiferromagnetic interaction J_2, novel magnetic states such as a spin-nematic state are theoretically expected. However, they have been rarely examined in experiments because of the difficulty in obtaining suitable model compounds. We show here that the quasi-one-dimensional antiferromagnet NaCuMoO_4(OH), which comprises edge-sharing CuO_2 chains, is a good candidate J_1-J_2 chain antiferromagnet. The exchange interactions are estimated as J_1 = - 51 K and J_2 = 36 K by comparing the magnetic susceptibility, heat capacity, and magnetization data with the data obtained using calculations by the exact diagonalization method. High-field magnetization measurements at 1.3 K show a saturation above 26 T with little evidence of a spin nematic state expected just below the saturation field, which is probably due to smearing effects caused by thermal fluctuations and the polycrystalline nature of the sample., 6 pages, 4 figures

${\mathrm{BiCu}}_{2}{\mathrm{PO}}_{6}$, a spin-gapped material in a frustrated two-leg ladder lattice, exhibits a complex $(H,T)$ phase diagram in external magnetic fields. We have characterized the field-induced phases through specific heat, magnetocaloric effect, Faraday rotation, and magnetization measurements in fields up to 120 T. In addition to observing a magnetic phase above 60 T which we attribute to the crystallization of triplet excitations, our measurements reveal the emergence and the subsequent disappearance of a high-entropy (short-range-ordered) phase at first and second critical magnetic fields, respectively. This is in good agreement with the theoretical prediction of a quantum soliton lattice at intermediate fields.

Magnetic and dielectric properties of \aa kermanite Ca$_2$CoSi$_2$O$_7$ single crystals were investigated in pulsed high magnetic fields. In magnetic fields along the $c$ axis, this material shows a magnetization plateau in a wide range of field below the saturation. Magnetization processes for fields along the $a$ and $b$ axes show multiple anomalies but different traces to each other, indicating the breaking of four-fold symmetry. Measurements of the magnetoelectric effects exhibit the changes in electric polarization according to the changes in the spin system. The experimentally determined quadratic magnetoelectric tensor is consistent with that expected in the crystal symmetry of orthorhombic $P2_12_12$., Comment: 11 pages, 5 figures

A spin-singlet ground state with a spin gap has been discovered in antiferromagnetic spin chain substances when the spin value is 1/2, 1, or 2. To find spin-gap (singlet-triplet) excitations in spin-$\frac{3}{2}$ chain substances, we performed inelastic neutron scattering and magnetization measurements on $R\mathrm{CrGeO}{}_{5}$ ($R=\text{Y}$ or Sm) powders. As expected, we observed spin-gap excitations and the dispersion relation of the lowest magnetic excitations. We proved that the spin system of $\mathrm{Cr}{}^{3+}$ was an antiferromagnetic alternating spin-$\frac{3}{2}$ chain. We describe the influence of frustration between nearest-neighbor and next-nearest-neighbor exchange interactions in the chain.

Magnetic properties of the layered itinerant system ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{Co}}_{2}{\mathrm{P}}_{2}$ were investigated under a magnetic field up to 70 T. As for the exchange-enhanced Pauli paramagnetic metal $\mathrm{Sr}{\mathrm{Co}}_{2}{\mathrm{P}}_{2}$, the magnetization curve shows two characteristic anomalies. The high-field anomaly corresponds to an itinerant-electron metamagnetic transition (IEMT), while the low-field one is small and broad without any obvious hystereses just as the crossover phenomenon between different energy states. Such a successive transition in the magnetization curve cannot be explained by the conventional phenomenological theory for IEMT based upon the Landau expansion of the magnetic free energy, but by the extended Landau expansion theory dealing with two distinguishable energy states. In the systematical study on ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{Co}}_{2}{\mathrm{P}}_{2}$, furthermore, the metamagnetic transition field decreases and goes to zero as $x$ increases up to 0.5, indicating that the ferromagnetic quantum critical point exists at $x\ensuremath{\sim}0.5$.

The magnetic and dielectric properties under high magnetic fields are studied in the single crystal of Cu3Mo2O9. This multiferroic compound has distorted tetrahedral spin chains. The effects of the quasi-one dimensionality and the geometrical spin frustration are expected to appear simultaneously. We measure the magnetoelectric current and the differential magnetization under the pulsed magnetic field up to 74 T. We also measure the electric polarization versus the electric field curve/loop under the static field up to 23 T. Dielectric properties change at the magnetic fields where the magnetization jumps are observed in the magnetization curve. Moreover, the magnetization plateaus are found at high magnetic fields.

We report magnetization, specific heat, and NMR measurements of 3-Br-4-F-V [=3-(3-bromo-4-fluorophenyl)-1,5-diphenylverdazyl], a strong-rung S=1/2 Heisenberg spin ladder with ferromagnetic leg interactions. We explain the magnetic and thermodynamic properties based on the strong-rung regime. Furthermore, we find a field-induced successive phase transition in the specific heat and the nuclear spin-lattice relaxation rate 1/T1. 19F-NMR spectra for higher- and lower-temperature phases indicate partial magnetic order and incommensurate long-range order, respectively, evidencing the presence of frustration due to weak interladder couplings., 12 pages, 3 figures

We investigate quantum computational complexity of calculating partition functions of Ising models. We construct a quantum algorithm for an additive approximation of Ising partition functions on square lattices. To this end, we utilize the overlap mapping developed by Van den Nest, D\"ur, and Briegel [Phys. Rev. Lett. 98, 117207 (2007)] and its interpretation through measurement-based quantum computation (MBQC). We specify an algorithmic domain, on which the proposed algorithm works, and an approximation scale, which determines the accuracy of the approximation. We show that the proposed algorithm does a nontrivial task, which would be intractable on any classical computer, by showing the problem solvable by the proposed quantum algorithm are BQP-complete. In the construction of the BQP-complete problem coupling strengths and magnetic fields take complex values. However, the Ising models that are of central interest in statistical physics and computer science consist of real coupling strengths and magnetic fields. Thus we extend the algorithmic domain of the proposed algorithm to such a real physical parameter region and calculate the approximation scale explicitly. We found that the overlap mapping and its MBQC interpretation improves the approximation scale exponentially compared to a straightforward constant depth quantum algorithm. On the other hand, the proposed quantum algorithm also provides us a partial evidence that there exist no efficient classical algorithm for a multiplicative approximation of the Ising partition functions even on the square lattice. This result supports that the proposed quantum algorithm does a nontrivial task also in the physical parameter region., Comment: 18 pages, 12 figures

$S$ = 1/2 quantum-spin systems of the kagome lattice have received intense recent attention because they are expected to be promising candidates for novel quantum states such as spin liquid, spin nematic, and other unknown exotic states. Here we report an unusual transition in a highly two-dimensional and slightly distorted $S$ = 1/2 quantum kagome system ${\mathrm{Cd}}_{2}{\mathrm{Cu}}_{3}{\mathrm{(OH)}}_{6}({\mathrm{SO}}_{4}){}_{2}{\mathrm{4H}}_{2}$O, which is a purified compound of the recently identified mineral edwardsite, Cd${}_{1.89}$Zn${}_{0.11}$${\mathrm{Cu}}_{3}{\mathrm{(OH)}}_{6}({\mathrm{SO}}_{4}){}_{2}{\mathrm{4H}}_{2}$O. The $S$ = 1/2 spins of Cu${}^{2+}$ ions form a highly two-dimensional kagome lattice with an extraordinarily large interlayer spacing g10 \AA{}, thus providing a unique kagome lattice with minimum interlayer perturbation. The magnetization shows a Curie-Weiss temperature of 40.5 K and moment freezing below around ${T}_{F}$ = 5 K and a magnetic transition feature near 3 K. The muon spin relaxation shows static magnetism below 5 K and saturation below 3 K. However, distinct features have been observed distinguishing it from a spin glass or a conventional order: High-field magnetization until 50 T showed a saturated value of only 1/3 of the full expected moment. Analysis of specific heat suggests that only 1/3 of the spins are related to the magnetic order; on the other hand, the order is destroyed in external field and 1/3 of the spins respond to the field with a Schottky-like behavior while the other 2/3 of the spins remain inactive. These experimental results suggest an unconventional coexistence of the partial order and most probably spin singlets.

Magnetization measurements and magnetotransmission spectroscopy of the solid oxygen α phase were performed in ultrahigh magnetic fields of up to 193 T. An abrupt increase in magnetization with large hysteresis was observed when pulsed magnetic fields greater than 120 T were applied. Moreover, the transmission of light significantly increased in the visible range. These experimental findings indicate that a first-order phase transition occurs in solid oxygen in ultrahigh magnetic fields, and that it is not just a magnetic transition. Considering the molecular rearrangement mechanism found in the O(2)-O(2) dimer system, we conclude that the observed field-induced transition is caused by the antiferromagnetic phase collapsing and a change in the crystal structure.

We determined the crystal structure of Ba$_2$CoSi$_2$O$_6$Cl$_2$, which was synthesized in this work, and investigated its quantum magnetic properties using single crystals. This compound should be described as a two-dimensionally coupled spin-1/2 XY-like spin dimer system. Ba$_2$CoSi$_2$O$_6$Cl$_2$ exhibits a stepwise magnetization process with a plateau at half of the saturation magnetization, irrespective of the field direction, although all the Co$^{2+}$ sites are equivalent. This indicates that spin triplets are localized owing to the almost perfect frustration of interdimer exchange interactions. Thus, the spin states for the zero and 1/2 magnetization-plateau states are almost exactly given by the simple product of singlet dimers and the alternate product of singlet and triplet dimers, respectively., Comment: 8 pages, 8 figures, published in J. Phys. Soc. Jpn. http://dx.doi.org/10.7566/JPSJ.83.103701

Anionic polymerizations of ortho-, meta-, and para-substituted styrene derivatives with alkoxy-methyl groups have been studied. It was found that their polymerization behaviors were significantly affected by the substituted position of the alkoxymethyl group. The meta- and ortho-substituted styrenes successfully underwent living anionic polymerization in THF at -78°C with the initiators having K + as a counter cation such as cumyl-potassium and oligo (α-methylstyryl ) potassium, and potassium napthalenide. On the other hand, no appreciable polymerization of the para-substituted styrenes occured under the identical conditions. The similar positional effect was also observed in the reactions of polystyryl-lithium with o,o-, m,m-, and p,p-disubstituted 1,1-diphen-ylethylene (DPE) derivatives with methoxymethyl groups. Instead of the expected 1 : 1 addition products, undesirable high molecular weight polymers were formed especially using p,p-disubstituted DPE. In order to account for such anomalous polymerization and reaction behaviors of the para-substituted styrene and DPE derivatives, we postulated the reaction pathway based on the anion-mediated rearrangement followed by a 1,6-elimination reaction to produce very reactive p-xylylene and/or biradical inter-mediates that were coupled to each other. This postulated reaction pathway was discussed throughout the results of the stoichiometric reaction of sec-BuLi with p-methoxy-methylstyrene and 1-(4-methoxymethylphenyl)-1-pheny-lethylene.

In this paper, temperature and field dependent magnetization processes of Ni films are studied. Polycrystalline Ni films are deposited on n-type GaAs (0 0 1) and Si (0 0 1) substrates by both the usual thermal evaporation and the UHV deposition in a MBE system. The roughness and the inherent oxide layer of the substrate are taken into consideration while preparing the Ni film on GaAs substrate. For a comparative study, similar Ni films deposited on glass substrate and a bulk Ni sample are investigated as well. At low temperature, considerably large applied fields are required to gradually saturate the Ni/GaAs films, starting from the end of the hysteresis. As an associate phenomenon, a large reduction of the remanent moment is observed. Coercive field as high as 71 mT is observed for this Ni film on GaAs substrate at 4.2 K. These anomalous magnetic behaviors are considered to be the effects of GaAs substrate, as they do not appear in Ni films deposited on Si substrate, glass substrate, and in the bulk Ni sample. A local antiferromagnetic interaction among the Ni spins at the interface of Ni and GaAs has been speculated. This interaction becomes stronger as the temperature goes below the room temperature.

Ameloblastic fibro-odontoma is the unique entity of epithelial–ectomesenchymal odontogenic tumors, which is characterized by enamel formation in addition to dentine. We examined immunohistochemically a case of this tumor in which enamel having prism structures was developed in the absence of odontoblast differentiation but was in contact with mesenchymal matrices. Histological examination showed diverse morphological features of epithelial tumor cells, e.g., cuboidal cells comprising tooth bud-like projections, ameloblast- and stellate reticulum-like cells, and residual cells in forms of extended cords or islands of odontogenic epitheilium. Immunostaining with anti-amelogenin sera proved that the intracellular production of amelogenins was initiated at the tooth bud-like stage. The secreted amelogenins were detected almost exclusively in the induced enamel and dentinoid areas, as well as in the core region of cementicle-like spheres deposited in the encapsulating stroma. The results obtained indicate that the odontogenic tumor epithelia and its products, i.e., amelogenins, participate in multifaceted aspects of dental hard tissue formation that takes place during oncogenesis.

Ni nanowires fabricated on a GaAs substrate, which have width narrower than 500 nm and thickness 50 nm, showed an antiferromagnetic-like domain structure. Many Ni nanowires fabricated on GaAs using the electron beam lithography technique have been studied by electron spin resonance (ESR). Splitting of ESR signals in the frequency-field diagram was observed around 57 GHz, although only a ferromagnetic resonance mode was observed for other frequencies. This mode is suggested to be an antiferromagnetic resonance related to the domain structure on the Ni nanowires.

JTV-803, 4-[(2-amidino-1,2,3,4-tetrahydroisoquinolin-7-yloxy)methyl]-1-(4-pyridinyl)piperidine-4-carboxylic acid monomethanesulfonate trihydrate, at ≥0.1 mg/kg/h inhibited the increase in plasma thrombin–antithrombin III complex in response to continuous infusion of thromboplastin in rats. JTV-803 inhibited thrombus formation in an arteriovenous shunt model by intravenous infusion at ≥0.3 mg/kg/h and prolonged the occlusion time of photochemically induced arterial thrombus in the middle cerebral artery at >1.5 mg/kg/0.5 h. Activated partial thromboplastin time was prolonged at 10 mg/kg/h. Intravenous administration of JTV-803 prolonged bleeding time at 30 mg/kg/h, a dose 10–100 times higher than the dose that inhibited thrombus formation. Compared with thrombin inhibitor, JTV-803 had less of an effect on the bleeding time. In the arteriovenous shunt model in cynomolgus monkey, JTV-803 prolonged the occlusion time when administered by continuous infusion at 0.3 mg/kg/h or orally at 10 mg/kg. These results suggest that the human factor Xa inhibitor JTV-803 is an orally active anticoagulant that does not affect bleeding time and is useful for the prevention of thrombus.

We have succeeded in synthesizing single crystals of an organic radical $p$-Br-V [3-(4-bromophenyl)-1,5-diphenylverdazyl]. The dominant intermolecular interactions forming a one-dimensional spin chain are deduced from the molecular packing in the crystal, and the ab initio molecular orbital calculation also indicates such an exchange network. We analyzed the magnetic susceptibility, magnetization curve, and magnetic specific heat through the quantum Monte Carlo method and successfully explained them as being attributed to an $S=\frac{1}{2}$ Heisenberg antiferromagnetic chain. Furthermore, we have found an unexpected successive phase transition in the specific heats, which indicates the formation of a noncollinear magnetic structure induced by frustration.

We have succeeded in synthesizing single crystals of the verdazyl radical $\ensuremath{\beta}$-3-(2,6-dichlorophenyl)-1,5-diphenylverdazyl. The $ab$ $initio$ molecular orbital calculation indicates the formation of an $S=1/2$ Heisenberg antiferromagnetic chain with fourfold magnetic periodicity consisting of three types of exchange interactions. We successfully explain the magnetic and thermodynamic properties based on the expected spin model by using the quantum Monte Carlo method. Furthermore, we reveal that the alternating and unique Ising ferromagnetic chains become effective in the specific field regions and observe a cooperative phenomenon caused by the magnetic order and quantum fluctuations. These results demonstrate that the verdazyl radical could form an unconventional spin model with interesting quantum behavior and provide a way to study a variety of quantum spin systems.

BaIrO3 adopts the 9R polytype structure if it is synthesized at ambient pressure. High-pressure and high-temperature treatments up to 10 GPa have led to other 5H and 6H polytype phases, which are quenchable to the ambient condition. However, the single-phase 3C perovskite, the end member of polytypes, has not been obtained so far. Here we report the high-pressure synthesis of BaIrO3 perovskite under 25 GPa and 1150 degrees C. Rietveld refinement on the powder x-ray diffraction pattern revealed that this new compound crystallizes in a tetragonal I4/mcm structure rather than the expected cubic Pm-3m structure. The new perovskite is a Pauli paramagnetic metal with a Fermi liquid ground state, i.e., rho proportional to T-2 below 6 K. The availability of BaIrO3 perovskite also allows completion of the structure-physical property evolution in the AIrO(3) perovskites (A = Ca, Sr, Ba). The Fermi energy located in bands originated from Ir: 5d and O: 2p electrons are found to be very sensitive to the change of crystal structure.

A magnetization study of a Tm${}_{2}$Fe${}_{17}$ single crystal and aligned powder of the deuteride Tm${}_{2}$Fe${}_{17}$D${}_{3.2}$ has been carried out in steady (14 T) and pulsed (60 T and, in one case, up to 74 T) magnetic fields at temperatures between 1.5 and 300 K. Tm${}_{2}$Fe${}_{17}$ is a ferrimagnet with ${T}_{C}$ $=$ 295 K and a spontaneous moment of 22 ${\ensuremath{\mu}}_{B}$/f.u. at $T$ $=$ 4.2 K. Of particular interest are low-temperature magnetization curves along the sixfold crystal axis $c$, which is an easy direction in Tm${}_{2}$Fe${}_{17}$ and a hard direction in the deuteride. In either case the magnetization increases with magnetic field undulatorily in broad steps whose height is a multiple of the atomic moment of Tm, ${\ensuremath{\mu}}_{\mathrm{Tm}}$ $=$ 7 ${\ensuremath{\mu}}_{B}$. In Tm${}_{2}$Fe${}_{17}$, the positions of the steps yield information on the Fe-Tm molecular field, 48 T on the Tm 2$d$ site and 60 T on the Tm 2$b$ site, whereas the crystal field parameter ${A}_{66}$ is found from the widths of the steps: ${A}_{66}$($b$) $=$ $\ensuremath{-}$35 K${a}_{0}^{\ensuremath{-}6}$ and ${A}_{66}$($d$) $=$ $\ensuremath{-}$26 K${a}_{0}^{\ensuremath{-}6}$ (here ${a}_{0}$ is the Bohr radius). It also proves possible to estimate the other sixth-order crystal field parameter: ${A}_{60}$ \ensuremath{\sim} \ensuremath{-}4 K${a}_{0}^{\ensuremath{-}6}$ (on average for both sites). Less information can be extracted from the powder data for the deuteride. Thus, the mean molecular field on Tm in Tm${}_{2}$Fe${}_{17}$D${}_{3.2}$ is found to be 49 T or 9$%$ less than in the parent binary compound.

Using X-ray diffraction technique, we investigated the modulation of the bicontinuous cubic structure of monoacylglycerol (monoolein)-water systems by the presence of solutes. X-ray diffraction results demonstrated that chaotropic solutes (NaSCN, NaI, and urea) expand the lattice constants of fully hydrated monoolein in Pn3m cubic phase and on the other hand, that kosmotropic solutes (Na2SO4, NaCl, and sucrose) reduce the lattice constants. These results can be interpreted as suggesting that kosmotropes reduce the interfacial area and that chaotropes expand the interfacial area, by assuming independence of the molecular length of monoolein on the presence of solutes.

We have examined genetic alterations in 11 surgically removed oral squamous cell carcinomas (OSCCs) using comparative genomic hybridization (CGH) and laser scanning cytometry (LSC), which allow quantitative analysis of chromosomal abnormalities. CGH analysis revealed gains and/or losses of DNA sequence copy number in all tumors. Gains in DNA sequence copy number were detected frequently for chromosome arms 3q25-28 (6/11), 5p (6/11) and 8q (5/11), and losses in chromosome arms 18q (4/11), 19q (4/11), 17p (3/11), and 19p (3/11). Amplification of 5p was observed in two tumors. LSC detected DNA aneuploidy with DNA indices ranging from 1.30 to 1.82 in 6 of 11 tumors. The number of chromosomal aberrations was higher in DNA aneuploid tumors than in diploid tumors (8.17 vs 3.60/tumor, P