ALBERT

Description: Sub-seabed geological storage of CO 2 in the form of gas hydrate is attractive because clathrate hydrate stably exists at low temperature and high pressure, even if a fault occurs by diastrophism like a big earthquake. For the effective design of the storage system it is necessary to model the formation of CO 2 -hydrate. Here, it is assumed that the formation of gas hydrate on the interface between gas and water consists of two stages: gas diffusion through the CO 2 -hydrate film and consequent CO 2 -hydrate formation on the interface, between film and water. Also proposed is the presence of a fresh reaction interface, which is part of the interface between the gas and aqueous phases and not covered with CO 2 -hydrate. Parameters necessary to model the hydrate formation in sand sediment are derived by comparing the results of the present numerical simulations and the measurements in the literature. A mathematical model for the formation of CO 2 -hydrate in sand sediment is proposed for sub-seabed geological storage of CO 2 in the form of gas hydrate, considering gas diffusion through the CO 2 -hydrate film and the presence of a fresh reaction interface. CO 2 -hydrate formation was numerically simulated by solving a heat transfer equation.

Description: We report on the first clear detection of transient Extremely-Low-Frequency (ELF) signal caused by an extremely intense cosmic gamma-ray flare. On 2004 December 27, the brightest gamma-ray flare ever recorded was observed by numerous satellites. A transient ELF emission observed at Moshiri and Onagawa in Japan exactly coincided with the peak time of the flare, and its wide pulse width of ∼40 ms disfavors the possibility of lightning origin. Furthermore, the two horizontal components of ELF magnetic field data recorded at Esrange in Sweden showed clear transient Schumann resonance waveforms. The source direction determined by the Lissajous method roughly corresponds to the subflare point. The chance probability that a sprite occurs within 30 ms of the peak flare time is ∼0.025%, which again clearly excludes the sprite origin. Thus, a bright cosmic gamma-ray flare is a new source of transient ELF radio signals observed on the Earth, although the emission mechanism needs to be clarified in future.

Description: After the occurrence of the 2011 magnitude 9 Tohoku earthquake, the seismicity in the overriding plate changed. The seismicity appears to form distinct belts. From the spatiotemporal distribution of hypocenters, we can quantify the evolution of seismicity after the 2011 Tohoku earthquake. In some earthquake swarms near Sendai (Nagamachi-Rifu fault), Moriyoshi-zan volcano, Senya fault, and the Yamagata–Fukushima border (Aizu-Kitakata area, west of Azuma volcano), we can observe temporal expansion of the focal area. This temporal expansion is attributed to fluid diffusion. Observed diffusivity would correspond to the permeability of about 10 −15 (m 2 ). We can detect the area from which fluid migrates as a seismic low-velocity area. In the lower crust, we found seismic low-velocity areas, which appear to be elongated along N–S or NE–SW, the strike of the island arc. These seismic low-velocity areas are located not only beneath the volcanic front but also beneath the fore-arc region. Seismic activity in the upper crust tends to be high above these low-velocity areas in the lower crust. Most of the shallow earthquakes after the 2011 Tohoku earthquake are located above the seismic low-velocity areas. We thus suggest fluid pressure changes are responsible for the belts of seismicity. Temporal expansion of the focal area in some earthquake swarms near Sendai (Nagamachi-Rifu fault), Moriyoshi-zan volcano, Senya fault, and the Yamagata-Fukushima border (Aizu-Kitakata area, west of Azuma volcano) induced by the 2011 Tohoku-Oki earthquake was observed. This temporal expansion can be explained by fluid diffusion. We found seismic low-velocity areas, which is the possible areas with fluid, beneath the swarms. From the results, the induced earthquakes are thought to be affected by the possible fluid pressure change.

Description: We developed a method for classifying hydrometeor particle types, including cloud and precipitation phase and ice crystal habit, by a synergistic use of CloudSat/Cloud Profiling Radar (CPR) and Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO)/Cloud-Aerosol LIdar with Orthogonal Polarization (CALIOP). We investigated how the cloud phase and ice crystal habit characterized by CALIOP globally relate with radar reflectivity and temperature. The global relationship thus identified was employed to develop an algorithm for hydrometeor type classification with CPR alone. The CPR-based type classification was then combined with CALIPSO-based type characterization to give CPR-CALIOP synergy classification. A unique aspect of this algorithm is to exploit and combine the lidar's sensitivity to thin ice clouds and the radar's ability to penetrate light precipitation to offer more complete picture of vertically resolved hydrometeor type classification than has been provided by previous studies. Given the complementary nature of radar and lidar detections of hydrometeors, our algorithm delivers thirteen hydrometeor types: warm water, supercooled water, randomly-oriented ice crystal (3D-ice), horizontally-oriented plate (2D-plate), 3D-ice+2D-plate, liquid drizzle, mixed-phase drizzle, rain, snow, mixed-phase cloud, water+liquid drizzle, water+rain and unknown. The global statistics of three-dimensional occurrence frequency of each hydrometeor type revealed that 3D-ice contributes the most to the total cloud occurrence frequency (53.8%), followed by supercooled water (14.3%), 2D-plate (9.2%), rain (5.9%), warm water (5.7%), snow (4.8%), mixed-phase drizzle (2.3%), and the remaining types (4.0%). This hydrometeor type classification provides useful observation-based information for climate model diagnostics in representation of cloud phase and their microphysical characteristics.

Description: [1]  Using a simultaneous and common-volume observation by a European incoherent scatter (EISCAT) VHF radar and a sodium lidar at Tromsø, Norway (69.6 ° N, 19.2 ° E), we have determined, for the first time, the effect of pure particle precipitation, excluding that of the electric field, on sodium density variations. Our observation on 24–25 January 2012 showed that sodium atom density decreased when there was no ion temperature enhancement (indicating a weak electric field) and the electron density increased (indicating strong particle precipitation). From the results we have concluded that auroral particle precipitation induced sodium atom density decrease in this event. Furthermore, a discussion is provided regarding the time response of the decrease in sodium density.

Description: Four distinct intragenic polymorphisms in the coagulation factor IX gene which have been reported to be important for family diagnosis of Caucasian hemophilia B were studied in 51 normal Japanese subjects (21 males and 30 females). High-molecular-weight DNA prepared from peripheral blood lymphocytes were digested with endonuclease, Ddel, Mspl, Taql or Xmnl, and were studied by Southern blot analysis with factor IX complementary DNA as a probe. None of the minor fragments produced by these enzymes was found in the normal Japanese DNA samples tested, although the probe detects minor allelic forms in control Caucasian DNA samples. Our data suggest that the frequent polymorphic sites found in Caucasians are possibly absent in the Japanese population.

Description: Although it is well established that the addition of 1,25- dihydroxyvitamin D3 (D3) to the culture of normal human granulocyte/macrophage progenitors induces monocyte/macrophage (Mo/M phi) colonies, the target cells of D3 in the Mo/M phi differentiation have not been identified. We examined whether neutrophilic promyelocytes are the target cells. As a source of the promyelocyte fraction, we used colonies after 5 days of culture (5-day colonies) of colony-forming unit-granulocyte. The culture contained granulocyte colony-stimulating factor (G-CSF) as the growth factor and generated only neutrophilic colonies. The promyelocytic nature of the 5-day colonies was confirmed morphologically, cytochemically, and ultrastructurally. After morphological evaluation on part of the individual colonies, they were transferred into new semisolid cultures with or without D3 (10(-7) mol/L) in the presence of G-CSF, then incubated for the subsequent 7 days. With D3, the colonies were loose, and all the constituent cells were morphologically small macrophages, which were positive for alpha-naphthyl butyrate (alpha NB) esterase, strongly positive for CD14 antigen, and plastic-adherent. While without D3, the colonies were rather compact, and all the constituent cells were morphologically mature neutrophils, which were positive for naphthol ASD-chloroacetate esterase and weakly positive for CD14 antigen. Secondary culture of the 8- or 10-day colonies with D3 induced a lower number of alpha NB-positive cells, in proportion to the percentage of promyelocytes at the time of transfer in each colony. Four days of secondary culture with D3 was sufficient to induce alpha NB-positive cells. G-CSF was not an essential factor to induce alpha NB- positive cells. These findings indicate that D3 differentiates normal human neutrophilic promyelocytes into the Mo/M phi lineage in vitro.

Description: Recently, it has been shown that the homozygous deletion of the cyclin- dependent kinase-4 inhibitor (CDK4I;p16) gene, which is mapped to chromosome 9p21, is frequently observed in a wide spectrum of human cancers, including leukemias. Therefore, the CDK4I gene is thought to be a putative tumor-suppressor gene. We report here that both alleles of the CDK4I gene were completely or partially deleted in human leukemia cells derived from both patients and established cell lines. Thirty-seven hematopoietic cell lines and samples from 72 patients with leukemias were examined for homozygous loss of the CDK4I gene locus by Southern blot analysis. We found that a part or the whole of the CDK4I gene was homozygously deleted in 14 of the 37 (38%) cell lines and 4 of 72 (6%) samples from leukemia patients, including 45 with acute myelocytic leukemia, 14 with acute lymphocytic leukemia (ALL), and 13 with chronic myelocytic leukemia in blastic crisis. In the cell lines, the homozygous deletion of the CDK4I gene was detected in a variety of cell lineages, whereas all 4 cases showing the homozygous deletion were confined to ALL. It should be noted that 2 of them had no cytogenetic abnormalities of chromosome 9. Our results suggest that loss of the CDK4I function may contribute to immortalization of human leukemia cells and play a causative role at least in development of human lymphocytic leukemias.

Description: The expression of adhesion molecules on human tonsillar follicular dendritic cells (FDCs) in the secondary lymphoid follicle (LF) in vivo and in vitro was investigated using cryostat sections and cytospin preparations of FDCs isolated with a magnetic cell sorter, respectively. FDCs were immunochemically positive for Mac-1 (CD11b), sialyl-Lex (CD15s), CD22, integrin beta 1 (CD29), CD40, very late activation antigen (VLA)-alpha 3 (CD49c), VLA-alpha 5 (CD49e), VLA-alpha 6 (CD49f), intercellular adhesion molecule (ICAM)-3 (CD50), ICAM-1 (CD54), B7 (CD80), and vascular cell adhesion molecule (VCAM)-1 (CD106). With respect to ligands on B cells for these adhesion molecules, the CD11b-CD54, CD50-leukocyte function-associated molecule (LFA)-1 (CD11a/18), and CD106-VLA-4 (CD49d/29) interactions in the apical light (ALZ) and basal light (BLZ) zones; the CD15s-L-selectin (CD62L) and CD106-CD49d/29 interactions in the mantle zone; and the CD54-CD11a/18 interaction in the entire LF may participate in FDC-B cell adhesion. Namely, the adhesion molecules participating in FDC-B cell interactions may differ in each of the five zones. Furthermore, the immunochemical evidence that FDCs were fibronectin (VLA-5, CD49e/29) and laminin (VLA-6, CD49l/29) receptor-positive discussed above was confirmed by immunoelectron microscopy and binding assays. Immunoelectron microscopy revealed fibers surrounded by cytoplasmic FDC extensions that were CD29-, CD49e-, and CD49f-positive. In the binding assays, the numbers of FDCs bound to fibronectin- and laminin-coated dishes and LFs of cryostat sections of human tonsils were reduced markedly by pretreatment with monoclonal antibodies against CD29, CD49e, and CD49f. These data indicate clearly that FDCs bind to reticulin and laminin fibers in LFs via their respective receptors.