Role of Multichance Fission in the Description of Fission-Fragment Mass Distributions at High Energies.

Fission-fragment mass distributions were measured for ^{237-240}U, ^{239-242}Np, and ^{241-244}Pu populated in the excitation-energy range from 10 to 60 MeV by multinucleon transfer channels in the reaction ^{18}O+^{238}U at the Japan Atomic Energy Agency tandem facility. Among them, the data for ^{240}U and ^{240,241,242}Np were observed for the first time. It was found that the mass distributions for all the studied nuclides maintain a double-humped shape up to the highest measured energy in contrast to expectations of predominantly symmetric fission due to the washing out of nuclear shell effects. From a comparison with the dynamical calculation based on the fluctuation-dissipation model, this behavior of the mass distributions was unambiguously attributed to the effect of multichance fission.

Associated factors of behavioural problems in children at preschool age: the Hokkaido study on environment and children's health.

BACKGROUND: Finding associated factors with childhood behavioural problems as early as preschool age is important. Studies have revealed several factors including socioeconomic factors, which may vary among different cultural background and population. However, investigation in general Japanese population of preschool age has not been well demonstrated. Thus, the objective of this study was to examine associated factors of childhood behavioural problems using Strengths and Difficulties Questionnaire (SDQ) in a prospective birth cohort study. METHODS: Total 3813 SDQ were distributed between October 2014 and December 2015 to the subpopulation of prospective birth cohort study, the Hokkaido Study on Environment and Children's Health. The subpopulation consisted of participants who had reached age 5 and were born between April 2008 and December 2010. Baseline questionnaire filled at recruitment and birth record were used to obtain participant information. Children with total difficulties score ≧ 13 were defined as likelihood of behavioural problems. A total of 2553 children with valid answers were included into the analysis. The response rate was 67.1%. RESULTS: Number of children with likelihood of behavioural problems was 521 (20.4%). Boys showed more problematic scores than girls. Multivariate analysis found that maternal pre-pregnancy BMI ≧ 30 kg/m2 , primipara, maternal education lower than high school, family income during pregnancy < 3 million yen/year and boy gender were the factors associated with increased odds ratio of likelihood of child behavioural problems. CONCLUSIONS: This study found that prenatal socioeconomic factors were associated with likelihood of child behavioural problems at preschool age in Japan.

Prognostic value of power doppler ultrasonography for equine superficial digital flexor tendon injury in thoroughbred racehorses.

The potential value of hypervascularity detected with power Doppler ultrasonography (PDU) within equine superficial digital flexor tendon (SDFT) as a prognostic factor of SDFT injury is not clear. The purpose of this study was to test the hypothesis that hypervascularity within SDFT is one of the risk factors for subsequent severe SDFT injury and to evaluate the prognostic value. A prospective cohort study of 97 Thoroughbred racehorses without any clinical signs of SDFT injury was conducted. Six variables of age, body weight, sex, the cross-sectional area of SDFT, PDU signal within SDFT and experience of steeplechase were assessed for the possibility of risk factors of subsequent SDFT injury in follow-up period of 1 year. Multivariable logistic regression analyses were used for assessment of the odds ratios (ORs) and 95 % confidence intervals (CIs) of SDFT injury. Multivariable logistic regression analysis revealed that the PDU signal within SDFT was a risk factor for the development of SDFT injury in follow-up period (P = 0.017). The adjusted OR of SDFT injury was significantly higher in PDU positive group than in PDU negative group (OR 3.17, 95 % CIs 1.20-8.35). Although further studies are required, these results would be useful for early detection and/or prevention of development for clinical severe SDFT injury.

Positional cloning of a gene for Hermansky-Pudlak syndrome, a disorder of cytoplasmic organelles.

Hermansky-Pudlak syndrome (HPS) is an often-fatal autosomal recessive disease in which albinism, bleeding, and lysosomal storage result from defects of diverse cytoplasmic organelles: melanosomes, platelet dense bodies, and lysosomes. HPS is the most common single-gene disorder in Puerto Rico, with an incidence of 1 in 1,800. We have identified the HPS gene by positional cloning, and found homozygous frameshifts in this gene in Puerto Rican, Swiss, Irish and Japanese HPS patients. The HPS polypeptide is a novel transmembrane protein that is likely to be a component of multiple cytoplasmic organelles and that is apparently crucial for their normal development and function. The different clinical phenotypes associated with the different HPS frameshifts we observed suggests that differentially truncated HPS polypeptides may have somewhat different consequences for subcellular function.

Transient ligation of umbilical vessels elevates placental tissue oxygen index (TOI) values measured by near-infrared spectroscopy (NIRS) in clawn miniature pig animal model.

We recently found a significant elevation in placental tissue oxygen index (TOI) values in cases of fetal growth restriction using near-infrared spectroscopy (NIRS), indicating high oxygenation in the placental tissue. We hypothesized that insufficient fetoumbilical blood flow is causatively associated with high oxygenation levels in placental tissue. We transiently (for 15 sec) ligated the whole umbilicus, umbilical arteries, or veins of pregnant Clawn miniature pigs (102-113 days of gestation) and assessed the changes in TOI values of the placenta and fetus. The ligation significantly increased placental TOI values (p<0.01, respectively), but concomitantly decreased fetal TOI values (p<0.01, respectively), suggesting a decline in oxygen inflow from the maternal to fetal circulation in the placental tissue to be causative of the elevated placental TOI values. These observations suggest the promising clinical use of placental TOI values measured noninvasively by the transabdominal application of NIRS to assess the fetoplacental circulation.

Discharge characteristics of steady-state high-density plasma source based on cascade arc discharge with hollow cathode.

We developed a steady-state high-density plasma source by applying a hollow cathode to a cascade arc discharge device. The hollow cathode is made of a thermionic material (LaB6) to facilitate plasma production inside it. The cascade arc discharge device with the hollow cathode produced a stationary plasma with an electron density of about 1016 cm-3. It was found that the plasma source produces a strong pressure gradient between the gas feed and the vacuum chamber. The plasma source separated the atmospheric pressure (100 kPa) and a vacuum (100 Pa) when the discharge was performed with an argon gas flow rate of 5.0 l/min and a discharge current of 40 A. An analysis of the pressure gradient along the plasma source showed that the pressure difference between the gas feed and the vacuum chamber can be well described by the Hagen-Poiseuille flow equation, indicating that the viscosity of the neutral gas is the dominant factor for producing this pressure gradient. A potential profile analysis suggested that the plasma was mainly heated within cylindrical channels whose inner diameter was 3 mm. This feature and the results of the pressure ratio analysis indicated that the temperature, and, thus, viscosity, of the neutral gas increased with the increasing number of intermediate electrodes. The discharge characteristics and shape of the hollow cathode are suitable for plasma window applications.

Observation of long-distance radial correlation in toroidal plasma turbulence.

This Letter presents the discovery of macroscale electron temperature fluctuations with a long radial correlation length comparable to the plasma minor radius in a toroidal plasma. Their spatiotemporal structure is characterized by a low frequency of ∼1-3 kHz, ballistic radial propagation, a poloidal or toroidal mode number of m/n=1/1 (or 2/1), and an amplitude of ∼2% at maximum. Nonlinear coupling between the long-range fluctuations and the microscopic fluctuations is identified. A change of the amplitude of the long-range fluctuation is transmitted across the plasma radius at the velocity which is of the order of the drift velocity.

"Donut's shape" radiosurgical treatment planning for large cystic metastatic brain tumors.

BACKGROUND: Radiosurgical management of large cystic metastatic brain tumors represents a significant challenge. Nevertheless, modified dose planning has shown beneficial results in such cases. METHOD AND RESULTS: "Donut's shape" radiosurgical treatment planning is based on the chain-like application of multiple, small-sized isocenters for selective coverage of the contrast-enhancing tumor capsule and minimal irradiation of the central cystic area. Such an approach was used for the management of large cystic intracranial metastases, which were not accompanied by a significant mass effect and did not require immediate volume reduction. Treatment was done using Leksell Gamma Knife model C with automatic positioning system. The majority of treated lesions showed significant shrinkage after radiosurgery and no major complications were met. CONCLUSION: Large cystic metastatic brain tumors may be successfully treated with gamma knife radiosurgery alone using the proposed "donut's shape" dose planning with coverage of the contrast-enhancing tumor capsule by multiple small-sized isocenters.

Extended mapping and exploration of the vanadium dioxide stress-temperature phase diagram.

Single-crystal micro- and nanomaterials often exhibit higher yield strength than their bulk counterparts. This enhancement is widely recognized in structural materials but is rarely exploited to probe fundamental physics of electronic materials. Vanadium dioxide exhibits coupled electronic and structural phase transitions that involve different structures existing at different strain states. Full understanding of the driving mechanism of these coupled transitions necessitates concurrent structural and electrical measurements over a wide phase space. Taking advantages of the superior mechanical property of micro/nanocrystals of VO(2), we map and explore its stress-temperature phase diagram over a phase space that is more than an order of magnitude broader than previously attained. New structural and electronic aspects were observed crossing phase boundaries at high-strain states. Our work shows that the actively tuning strain in micro/nanoscale electronic materials provides an effective route to investigate their fundamental properties beyond what can be accessed in their bulk counterpart.

A new multi-tracer pellet injection for a simultaneous study of low- and mid/high-Z impurities in high-temperature plasmas.

A new multi-tracer technique in the Tracer-Encapsulated Solid Pellet (TESPEL) method has been developed in order to acquire simultaneously the information about the behaviors of various impurities, i.e., to study concurrently the behaviors of low- and mid/high-Z impurities in magnetically confined high-temperature plasmas. In this new technique, an inorganic compound (for example, lithium titanate, Li2TiO3) is proposed to be used as a tracer embedded in the core of the TESPEL, instead of pure elements. The results of the proof-of-principle experiment clearly demonstrate the applicability of the new multi-tracer technique in the TESPEL method for the simultaneous study of behaviors of low- and mid/high-Z impurities in high-temperature plasmas.

Interaction of C4-binding protein with cell-bound C4b. A quantitative analysis of binding and the role of C4-binding protein in proteolysis of cell-bound C4b.

Purified C4-binding protein (C4-bp) was shown to bind to cell-bound C4b by radioactive tracer techniques. With EAC4 bearing greater than 3,000 C4b-molecules/cell, the number of C4-bp molecules bound was directly proportional to the number of C4b molecule on the cell surface; EAC4 bearing less than 3,000 C4b-molecules/cell bound a very small amount of C4-bp. Scatchard analysis of binding of C4-bp indicated an equilibrium constant of 4.6 X 10(8) L/M and a maximum of 0.43 C4-bp molecules bound per C4b molecule, equivalent to an average of one molecule of C4-bp per two or three molecules of C4b. Fluid-phase C4b inhibited the binding of C4-bp to cell-bound C4b in a dose-dependent manner, whereas native C4 had little effect. C2 inhibited this binding and also released C4-bp from EAC4,C4-bp. However, C2 was 27 times less effective than unlabeled C4-bp on a molar basis and a considerable amount of C4-bp remained bound to C4b on the cell surface even in the presence of a large excess of C2. We also examined the cofactor activity of C4-bp in the cleavage of cell-bound C4b by C3b/C4b inactivator (I). Cleavage of the alpha' chain of C4b on the cell surface by I alone was incomplete and an intermediate cleavage product, alpha-75, was observed. When C4-bp bound to C4b on the cell surface, the alpha' chain of the C4b cleaved into three fragments, alpha 2, alpha 3, and alpha 4. The alpha 3, alpha 4, beta, and gamma peptides (C4c) were released into the fluid phase, and the alpha 2 fragment (C4d) remained linked covalently to the cell membrane via an ester bond. In some situations, therefore, C4-bp enhances the proteolytic activity of I on cell-bound C4b.

Sexual dimorphism of the fifth component of mouse complement.

Sexual dimorphism of mouse complement component 5 (C5) was detected by isoelectric focusing of desialated ethylenediamine tetraacetic acid (EDTA)-plasma on agarose gel, followed by immunofixation with anti-mouse C5. Male plasma displayed two C5 bands, basic and acidic, while female plasma had only a basic C5 band. In all mouse strains tested except C5-deficient strains, the identical patterns of the dimorphism were obtained. The basic and acidic C5 were antigenically and hemolytically indistinguishable from each other. In the neonatal mice of both sexes, the basic C5 was observed at the same levels, but the acidic C5 was only slightly detected. Injection of testosterone into mice resulted in an appearance of the acidic C5 in females and its increase in males. By contrast, injection of estradiol decreased the acidic C5. These results indicate that the expression of the acidic C5 is under the control of testosterone.

Solubilization of immune precipitates by six isolated alternative pathway proteins.

Immune precipitates were solubilized by the alternative pathway of complement assembled from isolated proteins, i.e., C3, factor B, factor D, properdin, C3b inactivator (C3bINA), and beta 1H. The kinetic curves of solubilization in the isolated system and in EGTA-serum were virtually indistinguishable. No requirement of other factors was apparent. Deletion of C3bINA and beta 1H from the complete mixture caused total consumption of C3 in the fluid phase and resulted in neither C3 binding to the complexes nor solubilization. Thus, the presence of a regulated fluid-phase reaction is essential for efficient fixation of C3 and the consequent solubilization. In addition, properdin plays an essential role in the complement-mediated solubilization in the presence of the two regulators. A large amount of C3 was incorporated into the antigen-antibody lattice. Solubilization of immune complexes started after the binding of one C3 molecule to one antibody molecule in the complexes, and the molar ratio of C3:antibody in the solubilized complexes also is approximately 1.

The mechanism of action of decay-accelerating factor (DAF). DAF inhibits the assembly of C3 convertases by dissociating C2a and Bb.

DAF is a 70,000-Mr membrane protein that inhibits the amplification of the complement cascade on the cell surface, and protects cells from damage by complement. The precise mechanism of action of DAF is not entirely clear. Purified DAF was incorporated into the membrane of EAC4b cells. EAC4b2 and EDAF AC4b2 cells were prepared with radiolabeled C2. The same amount of labeled C2 bound to both cells, showing that DAF does not prevent the binding of C2 zymogen to C4b. After adding Cl, the radioactivity of bound C2 dissociated more rapidly from EDAF AC4b cells than from EAC4b cells. In EAC4b cells, bound C2 was converted to C2a, which gradually dissociated into the supernatants. In the DAF-treated cells, on the other hand, a large amount of C2a rapidly appeared in the supernatants and only a small amount of C2a remained on the cells. In a similar experiment using EhuAC4b, DAF on human erythrocyte membrane also dissociated the C2a from the cells. These results were confirmed by hemolytic assay and the accelerated decay of C2a caused the rapid depletion of C2 from the fluid phase. In addition, we found that DAF functions on the alternative pathway C3 convertase, C3bBb in the same manner. Thus, DAF, which associates with C4b and C3b in the membrane, acts on C2a and Bb, but not on intact C2 and B, and dissociates them rapidly from the binding sites, thereby preventing the assembly of the classical and alternative pathways C3 convertases.

Diversity in junctional sequences associated with the common human V gamma 9 and V delta 2 gene segments in normal blood and lung compared with the limited diversity in a granulomatous disease.

The T cell receptor (TCR) junctional regions (N regions) of the common human V gamma 9 and V delta 2 gene segments were sequenced from the blood and lung of normal individuals (195 transcripts) and a group of individuals with sarcoidosis (220 transcripts), a granulomatous disease in which increased numbers of V gamma 9+ gamma/delta + T cells are often observed. In normal individuals, the vast majority (86%) of blood V gamma 9 transcripts used the J gamma P gene segment. In contrast to this restriction of J region usage, there was a large diversity of the junctional region, with less than 20% of blood V gamma 9 junctional regions showing identical sequences for any one normal individual. For the blood V delta 2 transcripts in normal individuals, there was restriction of J region usage, with 93% using J delta 1. The junctional regions were even more diverse than for V gamma 9, with a unique sequence observed in each transcript examined. Compared with blood, sequences from the normal lung showed a small increase in identical junctional regions, particularly in one individual where 46% of V gamma 9 transcripts examined were identical, suggesting a response of some gamma/delta T cells to antigens found in the lung in the normal state. In marked contrast to normals, some individuals with sarcoidosis had large numbers of V gamma 9 transcripts, as well as V delta 2 transcripts, sharing identical sequences. For V gamma 9 blood transcripts, two individuals showed 84 and 56% of junctional region sequences to be identical, respectively. Similarly, blood V delta 2 transcripts showed 43, 33, and 25% identical junctional region sequences in three individuals. In the sarcoid patient with the most striking over-representation of blood V gamma 9 junctional sequences, lung V gamma 9 transcripts showed increased (67%) use of the same junctional region sequence as in blood. This limited diversity of TCR junctional regions among some individuals with sarcoidosis suggests a response from specific stimuli, possibly antigenic, and that gamma/delta T cells may play a specific role in granuloma formation in sarcoidosis, as has been suggested in other granulomatous diseases.

Biased accumulation of T lymphocytes with "memory"-type CD45 leukocyte common antigen gene expression on the epithelial surface of the human lung.

Expression of alternatively spliced products of the CD45 leukocyte common antigen gene identifies two populations of blood T cells: "naive" T cells (containing CD45R-IV mRNA transcripts, CD45 220, 205 kD surface proteins detected with antibody 2H4) that respond poorly to recall antigens, and "memory" T cells (containing CD45R-0 mRNA transcripts, expressing CD45 180 kD protein, detected with antibody UCHL1) that respond promptly to recall antigens. While blood contains approximately equal numbers of "naive" and "memory" T cells, it is known that UCHL1+ "memory" T cells accumulate at sites of chronic inflammation. To test the concept that "memory" T cells are a feature of the T lymphocyte populations present in tissues chronically exposed to antigens in normals as well as in individuals with chronic inflammation, we evaluated T lymphocytes obtained from blood and the epithelial surface of the lower respiratory tract of normal individuals for the expression of specific CD45 surface protein isoforms and corresponding mRNA transcripts. Flow cytometric analysis of CD45 220, 205, and 180 kD surface proteins demonstrated that lung T cells of normals are dominated by UCHL1+ "memory" cells (86 +/- 2%) while autologous blood T cells have equal proportions of "memory" UCHL1+ and "naive" 2H4+ T cells. In addition, polymerase chain reaction analysis of CD45 mRNA transcripts revealed that the lung cells expressed CD45R-0 mRNA transcripts but 17-fold fewer CD45R-IV mRNA transcripts than autologous blood T cells (p less than 0.01). The pattern of lung T cells being dominated by CD45R-0 mRNA+, UCHL1+ "memory" T cells was also observed in individuals with chronic beryllium disease, an example of a chronic inflammatory disease in which antigen-specific T cells accumulate on the pulmonary epithelial surface. Like the normals, the lung T cells of the beryllium disease patients were dominated by CD45R-0 mRNA transcript+, UCHL1+, T cells. However, on a quantitative basis, the beryllium patients contained far greater numbers of T cells, i.e., the T cell populations on the surface of the normal and inflamed lung are similar in character ("memory" T cells) but differ in numbers (there are far more in the chronic inflammatory state). Thus, T cell populations on the epithelial surface of the normal lung likely reflect the chronic exposure to a diverse set of antigens, with a pattern that is qualitatively similar to that observed among T cells accumulating in response to a single antigen.

Preservation of erniettomorph fossils in clay-rich siliciclastic deposits from the Ediacaran Wood Canyon Formation, Nevada.

Three-dimensionally preserved Ediacaran fossils occur globally within sandstone beds. Sandy siliciclastic deposits of the Ediacaran Wood Canyon Formation (WCF) in the Montgomery Mountains, Nevada, contain two fossil morphologies with similar shapes and sizes: one exhibits mm-scale ridges and a distinct lower boundary and the other is devoid of these diagnostic features. We interpret these as taphomorphs of erniettomorphs, soft-bodied organisms with uncertain taxonomic affinities. We explore the cast-and-mould preservation of both taphomorphs by petrography, Raman spectroscopy, X-ray fluorescence microprobe and X-ray diffraction. All fossils and the surrounding sedimentary matrix contain quartz grains, iron-rich chlorite and muscovite. The ridged fossils contain about 70% larger quartz grains compared to the ridgeless taphomorph, indicating a lower abundance of clay minerals in the ridged fossil. Chlorite and muscovite likely originated from smectite and kaolinite precursors that underwent lower greenschist facies metamorphism. Kaolinite and smectite are inferred to have been abundant in sediments around the ridged fossil, which enabled the preservation of a continuous, distinct, clay- and kerogen-rich bottom boundary. The prevalence of quartz in the ridged fossils of the WCF and in erniettomorphs from other localities also suggests a role for this mineral in three-dimensional preservation of erniettomorphs in sandstone and siltstone deposits.

Tricorn protease--the core of a modular proteolytic system.

Large macromolecular assemblies have evolved as a means of compartmentalizing reactions in organisms lacking membrane-bounded compartments. A tricorn-shaped protease was isolated from the archaeon Thermoplasma and was shown to form a multisubunit proteolytic complex. The 120-kilodalton monomer assembled to form a hexameric toroid that could assemble further into a capsid structure. Tricorn protease appeared to act as the core of a proteolytic system; when it interacted with several smaller proteins, it displayed multicatalytic activities.

A comparative study of the diagnostic accuracy of ELISA systems for the detection of anti-neutrophil cytoplasm antibodies available in Japan and Europe.

OBJECTIVES: Primary systemic vasculitis associated with anti-neutrophil cytoplasm antibodies (ANCA) differs in its frequency and clinical expression between Japan and Europe. We sought to ascertain whether such differences arise from the performance of enzyme-linked immunosorbent assays (ELISAs) for ANCA. METHODS: Plasma samples from 64 consecutive Japanese patients with a clinical and histological diagnosis of primary systemic vasculitis including microscopic polyangiitis (MPA; n=52), Churg-Strauss syndrome (CSS; n=1), and Wegener's granulomatosis (WG; n=11), or those from disease controls with non-vasculitic glomerulonephritis (n=54) and healthy controls (n=55) were tested for the presence of myeloperoxidase (MPO) by ELISAs available in Japan (Nipro and MBL) and compared with those in Europe (Wieslab). The sensitivity and specificity were calculated for each ELISA, and its diagnostic performance was assessed by receiver operating characteristic curve analysis. RESULTS: The sensitivity and specificity of either MPO-ANCA assays for a diagnosis of MPA were 90.4% and 98.2% (Nipro), 88.2% and 96.3% (MBL), and 86.5% and 99.1% (Wieslab). The overall diagnostic performance, assessed as the area under curve of the MPO-ANCA ELISAs for MPA were 0.946+/-0.022 (Nipro), 0.970+/-0.017 (MBL), and 0.971+/-0.017 (Wieslab), while that of PR3-ANCA ELISAs for WG were 0.986+/-0.025 (Nipro), 0.993+/-0.017 (MBL), and 0.916+/-0.059 (Wieslab). CONCLUSIONS: The MPO-ANCA ELISAs commercially available in Japan exhibited high sensitivity and specificity for the diagnosis of ANCA-associated vasculitides and provided similar diagnostic value to those in Europe. These results facilitate further international comparison of ANCA-associated vasculitides between Japanese and European populations.

Development of a tracer-containing compact-toroid injection system.

The accumulation and behavior of impurities is one of the most important subjects in the development of magnetically confined fusion reactors because impurities can potentially cause cooling and worsen the confinement of the hot core plasma. Tracer-encapsulated solid pellets (TESPELs) have demonstrated some results for impurity injection for fusion-reactor plasma studies [N. Tamura et al., J. Phys. Conf. Ser. 823, 012003 (2017)]. However, the TESPEL technique has several shortcomings, for example, the penetration depth and the amounts of tracer impurities. In the present study, we have developed a tracer-containing, compact-toroid (TCCT) injection system that utilizes a magnetized coaxial plasma gun (MCPG). The discharge current through the MCPG sputters and ionizes the electrode material, and the Lorenz self-force accelerates it as a plasmoid. The MCPG easily accelerates a magnetized plasmoid to speeds greater than the ion thermal velocity of several tens of kilometers per second. The accelerated and ejected plasmoid that contains the tracer ions is itself a warm, ionized plasma. Therefore, a TCCT can potentially be injected into the core region of a target plasma with less adverse effect.