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The anion exchange behavior of 255No produced by the 248Cm(12C,5n) reaction has been investigated in 11.5M HCl, 4M HCl and 8M HNO3 to deduce the behavior of 'primordial 257No' produced via 248Cm(18O,5n)261Rf →α 257No before anion exchange separation in the 261Rf experiment. It was found that 255No is mostly eluted from the anion exchange column with these solutions. The contribution of 'primordial 257No' to the α-decay events of 261Rf in the 261Rf experiment was evaluated based on the present results.

A method to decrease photons generated by β particles by using a capillary tube in liquid scintillation α spectrometry is presented. Liquid scintillation counting of 241 Am and 152 Eu was performed with 200, 300, and 500 μm inner diameter (i.d.) PFA tubes as the detection cell. It was observed that the β component in the energy spectrum is located at the lower-energy region with a decreasing i.d. of the PFA tubes, and the α peak of 241 Am was separated from the β component.

Two isomeric states of ${}^{265}$Sg, i.e., ${}^{265}$Sg${}^{a}$ and ${}^{265}$Sg${}^{b}$, proposed in Ch. E. D\"ullmann and A. T\"urler [Phys. Rev. C 77, 064320 (2008)] were produced in the ${}^{248}$Cm(${}^{22}$Ne,5$n$)${}^{265}$Sg reaction. Decay properties of ${}^{265}$Sg${}^{a,b}$ were investigated with a rotating-wheel apparatus for $\ensuremath{\alpha}$ and spontaneous fission (SF) spectrometry under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. Based on genetically correlated $\ensuremath{\alpha}$-$\ensuremath{\alpha}$(-$\ensuremath{\alpha}$) and $\ensuremath{\alpha}$-SF decay chains, 18 and 24 events were assigned to ${}^{265}$Sg${}^{a}$ and ${}^{265}$Sg${}^{b}$, respectively. The half-life ${T}_{1/2}$ and $\ensuremath{\alpha}$-particle energy ${E}_{\ensuremath{\alpha}}$ of ${}^{265}$Sg${}^{a}$ were measured to be 8.5${}_{\ensuremath{-}1.6}^{+2.6}$ s and 8.84 $\ifmmode\pm\else\textpm\fi{}$ 0.05 MeV, respectively, and those of ${}^{265}$Sg${}^{b}$ were 14.4${}_{\ensuremath{-}2.5}^{+3.7}$ s and 8.69 $\ifmmode\pm\else\textpm\fi{}$ 0.05 MeV. As a daughter product of ${}^{265}$Sg${}^{a,b}$, the decay properties of the 3-s isomeric state in ${}^{261}$Rf, i.e., ${}^{261}$Rf${}^{b}$, were also derived: ${T}_{1/2}$ $=$ 2.6${}_{\ensuremath{-}0.5}^{+0.7}$ s, ${E}_{\ensuremath{\alpha}}$ $=$ 8.51 $\ifmmode\pm\else\textpm\fi{}$ 0.06 MeV, and SF branch ${b}_{\mathit{SF}}$ $=$ 0.82 $\ifmmode\pm\else\textpm\fi{}$ 0.09. These results confirm and refine the decay pattern suggested for the decay chain ${}^{269}$Hs $\ensuremath{\rightarrow}$ ${}^{265}$Sg${}^{a,b}$ $\ensuremath{\rightarrow}$ ${}^{261}$Rf${}^{a,b}$ $\ensuremath{\rightarrow}$ ${}^{257}$No $\ensuremath{\rightarrow}$ in D\"ullmann and T\"urler. The production cross sections for ${}^{265}$Sg${}^{a}$ and ${}^{265}$Sg${}^{b}$ were determined to be 180${}_{\ensuremath{-}60}^{+80}$ and 200${}_{\ensuremath{-}50}^{+60}$ pb at 117.8 MeV, respectively, and they are discussed by comparing with the literature data as well as the theoretical prediction.

The transfer of negative pions captured by hydrogen to heavier atoms has been investigated in a series of alcohols by measuring both 2γ rays from π0 decay and pionic X rays. Capture rates for the pionic hydrogen of different chemical states in the molecule were determined from a comparison between the data for the ordinary compound and the deuterated one. The external transfer in the condensed phase was revealed by the dependence of the capture rate of hydrogen on the number of carbon atoms in the alkyl group. The influence of the chemical structure on the transfer process is discussed with respect to the large difference between the relative transfer rates,Λ C=1.5±0.2 andΛ O = 4.5±0.4, corresponding to carbon and oxygen, respectively.

Atomic capture probabilities of negative pions in some metal hydrides were measured. The capture by a hydrogen atom was detected by means of a pair of the annihilation γ rays of π0 which had been produced by the charge-exchange reaction of π− with the capturing hydrogen nucleus (proton). This method ensures a high sensitivity and reliability of the measurements. The probabilities obtained were in agreement with previous measurements except for palladium hydride, which showed a much smaller probability than that given in the literature. The atomic capture of π− is well described in the framework of the large mesic molecular model, in which the proportionality constant reflects the chemical states of the capturing atoms and also the neighboring ones.

The transfer of negative pions captured by hydrogen to deuterium has been studied in H[sub 2]O+D[sub 2]O mixtures. The D[sub 2]O-concentration dependence of the transfer rate was analyzed on the basis of a phenomenological model in order to determine the transfer parameters. The fit gives an asymptotic transfer of about 42%, which is smaller than the previous results, but slightly larger than the value for H[sub 2]+D[sub 2] gas mixtures. A mesomolecular effect of HOD molecules was discussed on the basis of the concentration dependence of the transfer rate.

A new complex, [Re(6)S(8)Cl(5)ppy](3-) (ppy = 4-phenylpyridine), was synthesized and characterized. The complex showed red emission at 296 K in both the crystalline phase and CH(3)CN. The transient absorption spectrum of [Re(6)S(8)Cl(5)ppy](3-) revealed that the emissive excited state involved the {Re(6)(μ(3)-S)(8)} core-to-ligand charge-transfer character.

The half-life of the ground state of $^{229}\mathrm{Th}$ ($^{229}\mathrm{Th}$${}^{g}$) has become an important factor in nuclear technology, for example, in the geological disposal of nuclear spent fuel. However, the values reported in two previous studies are not in agreement. This study reevaluates the half-life of $^{229}\mathrm{Th}$${}^{g}$ by using a simple and reliable method. The $^{232}\mathrm{U}$/$^{233}\mathrm{U}$ activity ratio of a $^{232,233}\mathrm{U}$ sample was measured by high-resolution $\ensuremath{\alpha}$-particle spectrometry. Next, the $^{228}\mathrm{Th}$/$^{229}\mathrm{Th}$${}^{g}$ activity ratio of the Th sample, which was grown from the $^{232,233}\mathrm{U}$ sample, was also measured. The half-life of $^{229}\mathrm{Th}$${}^{g}$ was calculated from these activity ratios, the growth time, and the half-lives of $^{232}\mathrm{U}$, $^{233}\mathrm{U}$, and $^{228}\mathrm{Th}$. From the results of these five measurements, the half-life of $^{229}\mathrm{Th}$${}^{g}$ is determined to be 7932 $\ifmmode\pm\else\textpm\fi{}$ 55 yr at a confidence level of 2$\ensuremath{\sigma}$.

A new fluorescent molecular probe, 2,2'-(1E,1'E)-2,2'-(4-(dicyanomethylene)-4H-pyrane-2,6-diyl)bis(ethene-2,1-diyl)bis(sodium benzenesulfonate) salt (1), possessing the cyanopyranyl moieties and two benzene sulfonic acid groups was designed and synthesized to detect proteins in solution and for high-throughput SDS-PAGE. Compound 1 exhibited no fluorescence in the absence of proteins; however, it exhibited strong fluorescence on the addition of bovine serum albumin as a result of intramolecular charge transfer. Compared with the conventional protocols for in-gel protein staining, such as SYPRO Ruby and silver staining, 1 achieves higher sensitivity, even though it offers a simplified, higher throughput protocol. In fact, the total time required for protein staining was 60-90 min under optimum conditions much shorter than that required by the less-sensitive silver staining or SYPRO Ruby staining protocols. Moreover, 1 was successfully applied to protein identification by mass spectrometry via in-gel tryptic digestion, Western blotting, and native PAGE together with protein staining by 1, which is a modified protocol of blue native PAGE (BN-PAGE). Thus, 1 may facilitate high-sensitivity protein detection, and it may be widely applicable as a convenient tool in various scientific and medical fields.

Carbonic anhydrase 9 (CA9) is a glycoprotein present on the surface of cell membranes. It is expressed in 90% of renal cancer cells, but not in normal kidney tissue. Immunotherapy targeting CA9 is underway, and our group has also conducted a clinical trial using CA9 as a cancer vaccine and confirmed the induction of cytotoxic T lymphocytes, with efficacy in some cases. Expression of CA9 antigen in oral cancer has not been reported in Japan, but our results indicate that immunotherapy targeting CA9 might be possible. We immunohistochemically observed the expression of antigens such as CA9, Ki-67, glucose transporter-1 (GLUT-1) and p53 in 107 subjects with oral squamous cell carcinoma, and examined their correlation with clinicopathological parameters. Immunostaining analysis showed expression of CA9 in 98% of oral cancer subjects, and the survival rate was significantly lower in subjects with CA9 antigen expression in 50% or more cells (P

The 1.9-s isomeric state ($^{261}\mathrm{Rf}$${}^{b}$) in $^{261}\mathrm{Rf}$ was directly populated in the $^{248}\mathrm{Cm}$($^{18}\mathrm{O}$,5$n$)$^{261}\mathrm{Rf}$${}^{b}$ reaction. Alpha and spontaneous fission (SF) decays of $^{261}\mathrm{Rf}$${}^{b}$, as well as the 68-s state $^{261}\mathrm{Rf}$${}^{a}$, was investigated with a rotating wheel apparatus under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. An identification of $^{261}\mathrm{Rf}$${}^{b}$ was based on $\ensuremath{\alpha}$-$\ensuremath{\alpha}$ correlations linking $\ensuremath{\alpha}$ decays of $^{261}\mathrm{Rf}$${}^{b}$ and its daughter $^{257}\mathrm{No}$. The $\ensuremath{\alpha}$-particle energy of $^{261}\mathrm{Rf}$${}^{b}$ was measured to be 8.52 \ifmmode\pm\else\textpm\fi{} 0.05 MeV. The half-life was determined to be 1.9 \ifmmode\pm\else\textpm\fi{} 0.4 s based on both 8.52-MeV $\ensuremath{\alpha}$ and SF decays. The $\ensuremath{\alpha}$ and SF branches are 0.27 \ifmmode\pm\else\textpm\fi{} 0.06 and 0.73 \ifmmode\pm\else\textpm\fi{} 0.06, respectively. The cross section for the $^{248}\mathrm{Cm}$($^{18}\mathrm{O}$,5$n$)$^{261}\mathrm{Rf}$${}^{b}$ reaction is \ensuremath{\sigma}($^{261}\mathrm{Rf}$${}^{b}$) = 11 \ifmmode\pm\else\textpm\fi{} 2 nb at 95.1 MeV, which gives a cross-section ratio of \ensuremath{\sigma}($^{261}\mathrm{Rf}$${}^{a}$)/\ensuremath{\sigma}($^{261}\mathrm{Rf}$${}^{b}$) = 1.1 \ifmmode\pm\else\textpm\fi{} 0.2.

The discrete molecular sulfide- and selenide-capped hexatechnetium(III) title complexes with axial cyano ligands are prepared from an octahedral hexatechnetium complex by depolymerization and axial ligand substitution and characterized by IR spectroscopy, UV/VIS spectroscopy, cyclic voltammetry, and DFT calculations.

Chalcogenide-capped molecular octahedral hexatechnetium(III) clusters [Tc(6)Q(8)(CN)(6)](4-) {Q = S ([1](4-)), Se ([2](4-))} were prepared by the substitution of axial ligands with cyanide. The structures of the new complexes were determined by single-crystal X-ray analysis. The IR spectra of [1](4-) and [2](4-) showed a C[triple bond]N stretching band at 2114 and 2105 cm(-1), respectively. In cyclic voltammetry, [1](4-) and [2](4-) in CH(3)CN showed reversible one-electron-oxidation waves assignable to the Tc(6)(24e/23e) process at +0.99 and +0.74 V, respectively. Density functional theory (DFT) calculations on the hexatechnetium complexes showed that the highest occupied molecular orbital (HOMO) was primarily localized on a Tc(6)Q(8) core and the lowest unoccupied molecular orbital (LUMO) was completely localized on the metal orbitals. The energy level of HOMO and the redox potential of the M(6)(24e/23e) process (M = Tc, Re) were found to have a good linear relationship. Time-dependent DFT calculations showed that the substantially allowed transitions with the lowest energy were Tc(6)Q(8) core-centered transitions. The electronic structures and electronic transition features of the hexatechnetium complexes were similar to those of the hexarhenium analogues [Re(6)Q(8)(CN)(6)](4-) (Q = S, Se); however, the energy gap between the HOMO and LUMO was smaller in the hexatechnetium complexes.

Photoluminescent properties of chalcobromide-capped octahedral hexarhenium(III) complexes with terminal bromide ligands [{Re(6)Q(8-n)Br(n)}Br(6)](n-4) (Q = Se, n = 1 ([1-Se](3-)), n = 2 ([2a-Se](2-) and [2b-Se](2-)), and n = 3 ([3-Se](-)); Q = S, n = 1 ([1-S](3-)), n = 2 ([2a-S](2-), [2b-S](2-), and [2c-S](2-)) were studied. The Q(7)Br capped complex [{Re(6)Q(7)Br}Br(6)](3-) and Q(6)Br(2) [{Re(6)Q(6)Br(2)}Br(6)](2-) (both D(3d) and C(2v) symmetric geometrical isomers) were successfully separated by column chromatography. All of the chalcobromide-capped complexes studied showed photoluminescence in both crystalline and solution phases. The emission maximum wavelength of the complexes at 296 K spans 853-915 or 868-968 nm in the crystalline phase or in acetonitrile, respectively. The selenobromide-capped complexes showed more intense emission as compared with the thiobromide analogues. The emission quantum yield (Phi(em)) and emission lifetime (tau(em)) became smaller and shorter, respectively, with an increase in the number of a capping bromide ligand in [{Re(6)Q(8-n)Br(n)}Br(6)](n-4). In the crystalline phase at 80 K, the emission maximum of the chalcobromide-capped complex shifted to the longer wavelength relative to that at 296 K. The emissive excited-state of the chalcobromide-capped hexarhenium(III) complexes was concluded to originate from the {Re(6)Q(8-n)Br(n)}(n+2) core with a spin-triplet type. The Phi(em) and tau(em) values of the {Re(6)Q(8-n)Br(n)}(n+2) complex were dependent significantly on the symmetry of the hexarhenium core, showing more intense emission for the complex with the higher symmetric core. A linear correlation between natural logarithm of the nonradiative decay rate constant and the emission maximum energy was observed for [{Re(6)Q(6)Br(2)}Br(6)](2-).

The standard of a primary specialized journal depends to a large extent on the quality of the peer-review process. During the last four years the following persons reviewed one or more manuscripts submitted to Radiochimica Acta, and gave advice to improve the presentations.

金沢大学理工研究域物質化学系, A gas-jet transport system has been coupled to the RIKEN gas-filled recoil ion separator GARIS to startup superheavy element (SHE) chemistry at RIKEN. The performance of the system was appraised using an isotope of element 104, 261Rf, produced in the 248Cm(18O,5n) 261Rf reaction. Alpha-particles of 261Rf separated with GARIS and extracted to a chemistry laboratory were successfully identified with a rotating wheel apparatus for α spectrometry. The setting parameters such as the magnetic field of the separator and the gas-jet conditions were optimized. The present results suggest that the GARIS/gas-jet system is a promising approach for exploring new frontiers in SHE chemistry: (i) the background radioactivities of unwanted reaction products are strongly suppressed, (ii) the intense beam is absent in the gas-jet chamber and hence high gas-jet efficiency is achieved, and (iii) the beam-free condition also allows for investigations of new chemical systems. © 2010 American Institute of Physics.

35歳男性のDyskeratosis congenita患者に発生した胃癌を経験した.Dyskeratosis congenitaは, 網状皮膚色素沈着, 爪甲異形成, 粘膜白板症を3主徴とするまれな先天性の外胚葉発育異常症であり, Zinsser-Cole-Engman syndromeともいわれる.予後不良疾患で, 50歳以上の延命は少なく, 粘膜白板症の癌化と再生不良性貧血による感染症が, 予後決定因子であるといわれている.症例の主訴は食思不振と体重減少で, 上部済化管X線検査と内視鏡検査で胃癌と診断し, 胃切除術を施行した.肝浸潤と腹膜播種を伴う胃前庭部中心のBorrmann 3型の管状腺癌であり, 粘膜白板は存在しなかった.Dyskeratosis congenitaでは, 粘膜白板症という前癌状態からの発癌とは別に, 消化管腺癌の若年期発生が高率であることが推測されるので, 本症患者の経過観察に際しては, この点に特に留意する必要があろう.

To search for a direct-decay signal from the isomer $^{229}\mathrm{Th}$${}^{m}$, $\ensuremath{\alpha}$-particle spectra of $^{229}\mathrm{Th}$${}^{m,g}$ produced from 93 mg of $^{233}\mathrm{U}$ have been measured by using a rapid and high-resolution $\ensuremath{\alpha}$-particle spectrometry, which can distinguish $\ensuremath{\alpha}$ lines of $^{229}\mathrm{Th}$${}^{m}$ from those of its ground state. Although $\ensuremath{\alpha}$ events were not obtained in the expected energy region for $^{229}\mathrm{Th}$${}^{m}$ with the exception of those derived from $^{229}\mathrm{Th}$${}^{g}$, we can estimate that the half-life of $^{229}\mathrm{Th}$${}^{m}$ is shorter than 2 h at $3\ensuremath{\sigma}$ confidence level under the chemical condition of chloride or hydroxide.

In the title compound, [UO(2)(C(4)H(7)O(3))(2)](n), the dioxouranium(VI) units are linked by 2-hydr-oxy-2-methyl-propionate ligands into a honeycomb structure. The U atom is seven-coordinate in a penta-gonal-bipyramidal geometry. The uncoordinated hydr-oxy groups of the 2-hydr-oxy-2-methyl-propionate ions inter-act with the O atom of the uranyl and with the coordinated hydr-oxy group of an adjacent 2-hydr-oxy-2-methyl-propionate ion through O-H⋯O hydrogen bonds.

Anion-exchange chromatography of element 105, dubnim (Db), produced in the 206 Cm( 19 F, 5n) 262 Db reaction is investigated together with the homologues Nb and Ta, and the pseudo-homologue Pa in 13.9 M hydrofluoric acid (HF) solution. The distribution coefficient (K d ) of Db on an anion-exchange resin is successfully determined by running cycles of 1702 chromatographic column separations. The result clearly indicates that the adsorption of Db on the resin is significantly different from that of the homologues and that the adsorption of anionic fluoro complexes of these elements decreases in the sequence of Ta ≈ Nb > Db > Pa.

Local fields in the vicinity of $^{111}\text{C}\text{d}(\ensuremath{\leftarrow}^{111}\text{I}\text{n})$ probes in different ZnO samples---0.5 at.% indium-doped and undoped---were measured by means of the time differential perturbed angular correlation method. Prominent aftereffect observed for the 0.5 at.% In-doped ZnO evidently exhibits an anomalous behavior of conduction electrons at a local scale: the probe site is off the mainstream of carrier electrons despite enhanced electric conductivity in the bulk. A remarkable observation of a drastic and discrete change in the electric field gradient at the probe in the different samples is also presented.

Rattling motion of the probe $^{140}\text{C}\text{e}(\ensuremath{\leftarrow}^{140}\text{L}\text{a})$ confined in the B cage of ${\text{LaB}}_{6}$ was observed by means of the time-differential perturbed angular correlation technique. The time scale of the motion is in the order of ${10}^{\ensuremath{-}11}\text{\ensuremath{-}}{10}^{\ensuremath{-}10}\text{ }\text{s}$ at room temperature. The activation energy of the slow motion at higher temperatures (160 to 773 K) was deduced to be ${E}_{a}=21.3(8)\text{ }\text{meV}$. At lower temperatures down to 10 K, a transitive state to motional freezing of the rattling was evidently observed, but the motion is still active for 76(2)% of the probe ions at this low temperature.

Formation of anionic fluoride-complexes of element 104, rutherfordium, produced in the 248 Cm( 18 O, 5n) 261 Rf reaction was studied by anion-exchange on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF 6 ] 2- , was formed in the studied fluoride ion concentrations of 0.0005-0.013 M. Formation of [RfF 6 ] 2- was significantly different from that of the homologues Zr and Hf, [ZrF 6 ] 2- and [HfF 6 ] 2- ; the evaluated formation constant of [RfF 6 ] 2- is at least one-order of magnitude smaller than those of [ZrF 6 ] 2- and [HfF 6 ] 2- .

Present status and perspectives of the superheavy element (SHE) chemistry at RIKEN are reviewed. A gas‐jet transport system for the SHE chemistry has been installed in the focal plane of the gas‐filled recoil ion separator GARIS at the RIKEN Linear Accelerator. The performance of the system was appraised using 206Fr and 245Fm produced in the 40Ar‐induced reactions on 169Tm and 208Pb, respectively. The α particles of 206Fr and 245Fm separated with GARIS and transported by the gas‐jet were clearly identified under desired low background condition with a rotating wheel system for α spectrometry. The high gas‐jet efficiencies over 90% are independent of the beam intensity up to 2 particle μA. A gas‐jet coupled SHE production system and a safety system for the usage of radioactive targets were also developed on the beam line of the RIKEN K70 AVF Cyclotron. The gas‐jet transport of 255No and 261Rf produced in the 238U(22Ne,5n)255No and 248Cm(18O,5n)261Rf reactions, respectively, was conducted for the future Sg ...

Muonic atom is an atomic system which has a negative muon substituted an electron. Muonic atom formation processes are strongly influenced by the chemical environment of muon capturing atom such as molecular structure, however, the initial processes of muon capture still have not been well investigated. In this study, we performed muon irradiation for gaseous carbon containing molecules to investigate the chemical environmental effect on muon capture processes.

We have developed a new target-irradiation system for the online preparation of multitracer solutions, where the nuclear-reaction products recoiling out of the target are directly implanted in a solvent as a liquid catcher. A rapid online transportation of the solution has enabled highly efficient recovery of the multitracer solutions having even short-lived radioactive isotopes without any chemical treatments. It has been suggested that the collection efficiency depends on the chemical properties of the recoil elements.

A technique for preparing nuclear reaction targets of various thicknesses was developed by using common filtration technique of hydroxide precipitates with a porous Al(2)O(3) membrane filter. Uniformity was found to be within a few % in each thickness. Durability for beam irradiation was also confirmed. The preparation procedure is convenient and the method is appropriate for several target materials, including not only precious materials but also radioactive materials with low contamination.

In order to improve utilisation of the multitracer method, two aspects of the method were pursued in this study. The production of radioisotopes from target fragmentation of 197Au nuclei was performed with high-energetic heavy ions of 12C (180, 290, 400 MeV/u) and 40Ar (290, 650 MeV/u) at HIMAC facilities. The yields of products were measured by using a thick-target-thickcatcher method and off-line γ-ray spectrometry with Ge semiconductor detectors. Besides, a special apparatus for practice of the radioisotope production was designed in application of the tracers for separation of the products from target material with high efficiency and the target material and shape for the design was investigated in a trial examination.

We report on the characteristic anion-exchange behavior of the superheavy element dubnium (Db) with atomic number Z=105 in HF/HNO3 solution at the fluoride ion concentration [F−]=0.003 M. The resul...

We report here on the successful oxidation of element 102, nobelium (No), on an atom-at-a-time scale in 0.1 M alpha-hydroxyisobutyric acid (alpha-HIB) solution using a newly developed technique, flow electrolytic column chromatography. It is found that the most stable ion, No(2+), is oxidized to No(3+) within 3 min and that the oxidized No complex with alpha-HIB holds the trivalent state in the column above an applied potential of 1.0 V.

An isotope of element 104, rutherfordium (261Rf), produced in the 248Cm(18O, 5n)261Rf reaction was successfully extracted to a chemistry laboratory using a gas-jet transport system coupled to the R...

When a subcutaneous mass is noticed in the anterior neck of a patient, we usually consider a diagnosis of skin tumour, lymph node swelling (1), or thyroid tumour (2). Vascular diseases, such as a tortuous major artery, aneu-rysm, or haemangioma are extremely rare (3–7). We describe here a case of a right tortuous innominate artery in which it proved impossible to detect pulsation because of the skeleto-muscular structures shielding the affected area. If either an aspiration or an open biopsy were to be performed near a tortuous innominate artery simulating a subcutaneous mass, a major artery might be damaged, possibly with lethal consequences. We present here clinical findings that call for caution in dealing with a tortuous innominate artery simulating a supraclavicular subcutaneous tumour.CASE REPORTA 73-year-old woman presented at our hospital complaining of an anterior neck mass that she had noticed only 4 weeks previously. She was not obese (BMI = 19.3), nor was her medical history regarding hypertension, hyperlipidaemia and syphilis particularly remarkable. She had no dyspnoea or dysphagia, but her husky voice and severe throat discomfort were clearly alarming. A fibroscopic examination revealed no abnormality in the pharynx or larynx. We palpated a 1.5-cm subcutaneous mass in the right supraclavicular fossa (Fig. 1), but were unable to detect any obvious pulsation of the mass. Ultrasonography revealed that our access to a view within the mass was blocked by the clavicle, which covered the lower part of the mass. Computerized tomography (CT) showed a tortuous innominate artery protruding from the mediastinal space (Fig. 2A). In addition, magnetic resonance angio-graphy (MRA) revealed that the forward and lateral arterial bending becomes the substance of the mass (Fig. 2B). From these examinations, we diagnosed it as a tortuous innominate artery simulating a subcutaneous neck tumour. Since her symptoms were not accompa-nied by neurological signs, we kept the patient under careful observation for 12 months. DISCUSSIONThis case revealed a tortuous innominate artery, which had initially been observed as a subcutaneous mass within a supraclavicular lesion. We could detect no obvious pulsation of the mass, but subsequent CT and magnetic resonance imaging (MRI) revealed a tortuous innominate artery. From our experience, when a sub-cutaneous tumour occurs near the clavicle, one should look for signs of an abnormal course of the innominate arteries, since their evanescent character is related to blood pressure levels (4). Initially, a radiological survey including CT, MRI, or MRA should be conducted.

We report on new and much more precise cation-exchange data of element 104, rutherfordium (Rf), in the fluoride ion concentration [F−] range of 5.29×10−5−1.04×10−3 M. The result based on one-atom-a...

The 1:2 reaction of [RuCl2(bpy)2] (bpy = 2,2′-bipyridine) with [Pd(aet)2] (aet = 2-aminoethanethiolate) led to the formation of [Ru(bpy)2{Pd2(aet)3}{Pd(aet)2}]3+ ([1]3+), which was converted into [...

Muon capture isotope detection (MuCID) is a non-destructive detection (assay) of composite and impurity nuclear isotopes by measuring γ rays following muon capture reaction products. Several nuclear isotopes are produced by muon capture reactions such as (μ, xn γ) with \(x = 0\), 1, 2, 3, and so on, and some of them are radioactive isotopes. The isotopes of the interest are identified by measuring γ rays characteristic of the reaction products by means of high-sensitivity Ge detectors. Composite and impurity nuclear isotopes of the orders of microgram–nanogram and ppm–ppb are investigated. The feasibility and the sensitivity of MuCID were shown experimentally by using μ capture reactions on Mo isotopes at MuSIC in RCNP. MuCID is used to study nuclear isotopes of astro-nuclear and particle physics interests and those of geological and historical interests.

A negative-pion capture process for several kinds of hydrocarbons was studied by the simultaneous observation of low-energy pionic x rays and ${\mathrm{\ensuremath{\pi}}}^{0}$ decays following the nuclear capture of pions by hydrogen. We measured the pionic x-ray intensity pattern and the pion-capture probabilities of constituent carbon and hydrogen. The x-ray intensity pattern depends on the chemical environment; a cascade calculation showed that this can be qualitatively attributed to the effects of a pion transfer from hydrogen. The pion-capture probabilities on hydrogen could be explained by a combined model involving a modified large mesomolecular model and an external transfer process. The external transfer parameter of the pion from a pionic hydrogen atom to carbon atoms was deduced to be ${\mathrm{\ensuremath{\Lambda}}}_{\mathrm{C}}$=1.7\ifmmode\pm\else\textpm\fi{}0.2 based on the results for a series of alkanes in the condensed phase. The large difference between the pion-capture probabilities on hydrogen observed in alkanes and that in benzene can be well understood based on the proposed model. \textcopyright{} 1996 The American Physical Society.

From January 1988 to January 1993, 45 patients with unresectable advanced hepatocellular carcinoma (HCC) were treated with a new combination therapy consisting of arterial infusion chemotherapy and TAE. The combination therapy was performed according to our treatment schedule as follows: two courses of arterial infusion chemotherapy were given first, and then transcatheter arterial embolization (TAE) using a mixture of Lipiodol and cisplatin powder was performed. Two arterial infusion chemotherapeutic regimens were employed: EPF (etoposide, cisplatin, and 5-fluorouracil) and EAP (etoposide, Adriamycin or Epi-adriamycin, and cisplatin). The anticancer drugs were infused through a catheter inserted into the proper or common hepatic artery. Assessment was made of the anticancer effect and survival rate of each treatment method. The response to each therapy was evaluated on the basis of CT performed prior to and after the treatment. In the EPF·TAE group, the response rate was about 46%, whereas in the EAP·TAE group it was 48%. Overall, 21 of 45 patients attained a regression rate of 50% or more. Furthermore, daughter nodules decreased in size or disappeared in about 67% of 15 patients. Additionally, tumor thrombi tended to show a similar response. In all of the cases, the average duration of survival was 30.3 months, and the 1-year survival value was 68%, the 2-year survival value was 44%, and the 3-year survival value was 35%. These results were superior to those obtained with TAE therapy alone.

The behavior of impurity atoms in graphite is one of the most intriguing subjects in current materials science. It is well known, for graphite intercalation compounds, that the type and concentration of intercalated impurities control their physical and chemical properties. It is thus of great importance to investigate the behavior of intercalants in the two dimensional layers for further understanding of their interacting nature with the graphite matrix. In order to investigate such interactions, it is essential to introduce impurities of interest into graphite; and, for that purpose, the ion-implantation method would be the simplest method. Nuclear techniques with radioactive probes are highly suited to such studies on the behavior of dilute impurities because of their high sensitivity. In our recent study, we developed a new detection apparatus for radioactive impurities: an online time-differential perturbed angular correlation (TDPAC) measurement system. The TDPAC method is a spectroscopy using unstable nuclei as the probe; by observing the time-variant angular correlation of rays successively emitted in the disintegration process of the excited nucleus of the probe, we can obtain direct information on the local field in the vicinity of the probe nucleus through electromagnetic interactions between the probe nucleus and extranuclear field. The newly developed system enables the application of shortlived unstable nuclei to the spectroscopy as the parents of probes; they are implanted in samples of interest at high energy immediately after their production by acceleratorbased nuclear reactions. In our previous paper, we demonstrated the applicability of the present online system and reported on the residence site of F( O) implanted in highly oriented pyrolytic graphite (HOPG). In comparison with the previous data obtained at 18K, we here discuss the displacement of the F( O) nuclei at room temperature on the basis of the damping trend of the TDPAC spectra. The online TDPAC experiment was carried out at the RIKEN Nishina Center. Ionized Ne was accelerated by a two-stage acceleration with the AVF cyclotron and the ring cyclotron up to 110MeV/u at a beam intensity of 150 pnA. A variety of radioactive nuclides were produced at a Be production target by projectile-fragmentation reactions; the secondary beam of interest, O (t1=2 1⁄4 26:9 s), was separated out of these heavy ions at a purity of 98% or higher by the RIKEN projectile-fragment separator (RIPS). A wellfocused pulsed beam of O was implanted deep in an HOPG sheet at a beam intensity of 10 s . The online TDPAC measurements were performed at room temperature on the 1357–197 keV cascade rays from F nuclei, whose 197 keV intermediate state with nuclear spin of I 1⁄4 5=2 has a half-life of 89.3 ns. In the present work, the time evolution of the angular correlations of the cascade rays was observed at =2 and directions. In order to obtain better counting statistics, we used sixteen BaF2 detectors. They were arranged in four independent detector planes for the investigation of the sample-to-detector configuration dependence of perturbation patterns for a single-crystalline sample. All the events were taken in a list mode using a CAMAC system so that we could work on off-line data processing searching for the optimum conditions on energy gates for the detected rays of interest. The experimental details are described elsewhere. The TDPAC spectra of F( O) implanted in the HOPG sheet at room temperature are shown in Fig. 1 together with the previous data obtained at 18K. In the present experiment, we derive the time evolution of the angular correlation as a function of the time interval between the cascade -ray emissions, RðtÞ, from the following simple arithmetic operation: -0.2

We have attempted to observe nuclear excitation by electron transition (NEET) in 235U with Mo K X-ray irradiation and off-line radioactivity measurement. Nuclear excitation of the 13-keV level was measured through the isomer radioactivity. An upper limit for the NEET probability was obtained as P < 9 × 10−10.