The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Deltam21(2) and stringent constraints on theta12. The exposure to nuclear reactor antineutrinos is ...increased almost fourfold over previous results to 2.44 x 10(32) proton yr due to longer livetime and an enlarged fiducial volume. An undistorted reactor nuovere energy spectrum is now rejected at >5sigma. Analysis of the reactor spectrum above the inverse beta decay energy threshold, and including geoneutrinos, gives a best fit at Deltam21(2)=7.58(-0.13)(+0.14)(stat) -0.15+0.15(syst) x 10(-5) eV2 and tan2theta12=0.56(-0.07)+0.10(stat) -0.06+0.10(syst). Local Deltachi2 minima at higher and lower Deltam21(2) are disfavored at >4sigma. Combining with solar neutrino data, we obtain Deltam21(2)=7.59(-0.21)+0.21 x 10(-5) eV2 and tan2theta12=0.47(-0.05)+0.06.
REBCO coated conductors are now available from several industrial manufacturers and are expected to be promising conductors for high-field-magnet applications. Using these conductors, the development ...of solenoids capable of generating high magnetic fields of 20-30 T is ongoing in major high-field laboratories in the world. In addition, CERN recently launched a conceptual design study for the Future Circular Collider, in which a 20-T dipole magnet is listed as a candidate for the bending magnet of the main ring. However, there has been limited research published on the electrical transport properties of commercially available REBCO conductors in a high-field, low-temperature environment. For magnet designers, the transport properties are of the highest importance in choosing a suitable conductor, and the data form the bases for high-field magnet development. Therefore, in this work, a new sample holder, which allows the measurements of full-width conductors to be carried out relatively easily, was developed, and the transport properties of commercial REBCO conductors from seven manufacturers (AMSC, Fujikura, Shanghai Superconductor, SuNAM, SuperOx, SuperPower, and SWCC Showa) were investigated at 4.2 K in perpendicular fields of up to 18 T. The results show that the Ic values at 4.2 K clearly vary to some extent among these commercial conductors and the higher-current 4-mm-wide conductors have Ic values in the range of 230-305 A at 18 T and in the range of 320-424 A at 12 T.
As a Japanese contribution to the High-Luminosity Large Hadron Collider (HL-LHC) upgrade, KEK is in charge of developing the beam separation dipole cold masses. The full-scale prototype magnet ...(MBXFP1) was constructed in Hitachi and powering test at cold was conducted at KEK. After the test, the magnet was returned to Hitachi for the final assembly of the cold mass. The pressure vessel design of the cold mass was carried out by KEK in accordance with ASME code. A new design of bus leads was proposed to satisfy the requirement of flexibility as well as mechanical support and electrical insulation. Welding of the extremity pipes was challenging due to tight position tolerance. This article reports the structure, pressure vessel design, and assembly of the LMBXF prototype cold mass (LMBXFP1) including bus work, instrumentation, and welding works with geometrical measurements.
PICK1 (protein interacting with C kinase-1) regulates the surface expression of the AMPA receptor (AMPAR) GluR2 subunit, however, the functional consequences of this interaction are not well ...understood. Previous work has suggested that PICK1 promotes the internalization of AMPARs. However, we found that when PICK1 is virally expressed in the CA1 region of hippocampal slices, it causes an increase in AMPAR-mediated EPSC amplitude. This effect is associated with increased AMPAR rectification and sensitivity to polyamine toxin. These effects are blocked by PKC or calcium/calmodulin-dependent protein kinase II inhibitors, indicating that the virally expressed PICK1 signals through an endogenous kinase cascade. In contrast, blockade of interactions with GluR2 at the N-ethylmaleimide-sensitive factor site did not cause a change in subunit composition, suggesting that the effects of PICK1 are not simply a nonspecific consequence of removing AMPARs from the surface. Immunocytochemical and biochemical analyses in dissociated cultured hippocampal neurons show that PICK1 causes a decrease in endogenous GluR2 surface expression but no change in GluR1 surface levels. To address the physiological role of PICK1, we virally expressed C-terminal GluR2 peptides. Blockade of endogenous PICK1 PDZ (postsynaptic density-95/Discs large/zona occludens-1) domain interactions produced opposite effects on synaptic strength and AMPAR rectification to those observed with PICK1 expression. This demonstrates that AMPAR subunit composition is physiologically regulated through a mechanism involving PICK1 PDZ domain interactions. These findings suggest that PICK1 acts to downregulate the GluR2 content of AMPARs at hippocampal CA1 synapses, thereby increasing synaptic strength at resting membrane potentials.
High Energy Accelerator Research Organization (KEK) is developing Nb-Ti based beam separation dipole (MBXF) for the high-luminosity Large Hadron Collider (HL-LHC) upgrade within the framework of ...CERN-KEK collaboration. This magnet produces field integral of 35 T*m in a 150 mm bore at 12 kA and 1.9 K. KEK has fabricated and tested three 2 m-long model magnets as in-house activities. After the technologies cultivated in these model magnet development was transferred from KEK to a manufacture, construction of the first full-scale prototype (MBXFP1) started in Hitachi. This paper reports test result of cold test for MBXFP1 including training, mechanical behavior, magnetic field quality and quench protection.
Magnetic properties of Cryophy were measured at room and cryogenic temperatures using ring samples. Sample-to-sample variation in permeability was evaluated in addition to measurement error. ...Permeability dependence on the maximum annealing temperature was examined using ring samples annealed at 1100 °C and 1170 °C. From these data, Cryophy was chosen as magnetic shielding material for the superconducting cavities in the main linac section of the cERL (compact Energy Recovery Linac) at KEK. Magnetic properties of Cryophy are presented along with the results of simulation based on the data obtained. The result of the high-power test of the cERL main linac cavities is reported at the end.
Use of antibiotics inevitably leads to antimicrobial resistance. Selection for resistance occurs primarily within the gut of humans and animals as well as in the environment through natural ...resistance and residual antibiotics in streams and soil. We evaluated antimicrobial resistance in Gram negative bacteria from a river system in a rural community in Bahia, Brazil. Water was collected from the Jiquiriçá and Brejões rivers and the piped water supply. Additionally, stools were collected from a random sample of residents, cows, pigs and horses near the river. The samples were screened for bacteria resistant to ciprofloxacin, cefotaxime, and meropenem and identified biochemically at the genus and species levels. Microbial source tracking demonstrated that ruminant and human fecal contamination increased as the rivers neared the village center and decreased after the last residence. Antibiotic bacteria were identified from all samples (n = 32). No bacteria were resistant to carbapenems, but the majority of the enterobacteria were resistant to ciprofloxacin, even though this class of antibiotics is not commonly used in food animals in this region. Considering these facts, together with the pattern of human fecal contamination, a human source was considered most likely for these resistant isolates.
Magnetic shielding is a key technology for superconducting RF cavities. The tolerance of the ambient magnetic field depends on factors such as the operating RF frequency and acceleration gradient, ...but can be lower than 1 μT. Conventional permalloy is often used for shielding low magnetic fields such as the earth's magnetic field. However, it is not well known how much the shielding effects degrade at cryogenic temperatures where superconducting cavities are operated. Some high Ni-content alloys, which are reported to maintain high permeability at cryogenic temperatures, are commercially available at present and are used for magnetic shielding of superconducting cavities at many laboratories. In this study, the magnetic properties of these materials are measured at room and cryogenic temperatures. The permeability dependence on the heat treatment conditions is studied by using one of the high Ni-content alloys. The effects of mechanical strain are also examined at room temperature. Evaluation of the magnetic shielding for the superconducting cavities of cERL is also discussed in this paper.
The development of a large-aperture (120-180 mm) dipole magnet is proposed in the framework of the CERN-KEK cooperation program. The application target is the D1 magnet (separation dipoles) ...replacement for the HL-LHC (High Luminosity-Large Hadron Collider) upgrade. The Cos-theta type coil cross section and the shell-based structure are adopted in the conceptual design of this magnet. The nominal field is estimated to be 6-10 T at 1.9 K with a 30-mm-width coil arranged in two layers. The candidates of superconductor are Nb 3 Al, and Nb-Ti. We present the analytical estimation of the key parameters of this magnet and the simulation of the actual design which includes the field quality, the stray field, and the stress distribution in the coil.
The SuperKEKB project underway at KEK will increase the KEKB luminosity by 40 times using nanobeam-interaction-region focusing optics. To achieve this high luminosity, the chromaticity correction of ...the collision beams is crucial; thus, special sextupole magnets, which can simultaneously produce normal and skew sextupole fields, are required in the straight sections around the interaction point. As a candidate for the sextupole, a cryocooled high-temperature superconducting magnet was proposed; development has begun. Here, the basic magnet design and the results of a small coil test are presented. The test studied the quench characteristics of the REBCO-impregnated coil.
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