|
A Fujiwara,
J Kawaguchi,
D K Yeomans,
M Abe,
T Mukai,
T Okada,
J Saito,
H Yano,
M Yoshikawa,
D J Scheeres,
O Barnouin-Jha,
A F Cheng,
H Demura,
R W Gaskell,
N Hirata,
H Ikeda,
T Kominato,
H Miyamoto,
A M Nakamura,
R Nakamura,
S Sasaki,
K Uesugi
Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan. fujiwara@planeta.sci.isas.jaxa.jp
During the interval from September through early December 2005, the Hayabusa spacecraft was in close proximity to near-Earth asteroid 25143 Itokawa, and a variety of data were taken on its shape, mass, and surface topography as well as its mineralogic and elemental abundances. The asteroid's orthogonal axes are 535, 294, and 209 meters, the mass is 3.51 x 10(10) kilograms, and the estimated bulk density is 1.9 +/- 0.13 grams per cubic centimeter. The correspondence between the smooth areas on the surface (Muses Sea and Sagamihara) and the gravitationally low regions suggests mass movement and an effective resurfacing process by impact jolting. Itokawa is considered to be a rubble-pile body because of its low bulk density, high porosity, boulder-rich appearance, and shape. The existence of very large boulders and pillars suggests an early collisional breakup of a preexisting parent asteroid followed by a re-agglomeration into a rubble-pile object.
Latest citations:
Keisuke Nagao,
Ryuji Okazaki,
Tomoki Nakamura,
Yayoi N Miura,
Takahito Osawa,
Ken-ichi Bajo,
Shintaro Matsuda,
Mitsuru Ebihara,
Trevor R Ireland,
Fumio Kitajima,
Hiroshi Naraoka,
Takaaki Noguchi,
Akira Tsuchiyama,
Hisayoshi Yurimoto,
Michael E Zolensky,
Masayuki Uesugi,
Kei Shirai,
Masanao Abe,
Toru Yada,
Yukihiro Ishibashi,
Akio Fujimura,
Toshifumi Mukai,
Munetaka Ueno,
Tatsuaki Okada,
Makoto Yoshikawa,
Junichiro Kawaguchi
Geochemical Research Center, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan. nagao@eqchem.s.u-tokyo.ac.jp
Noble gas isotopes were measured in three rocky grains from asteroid Itokawa to elucidate a history of irradiation from cosmic rays and solar wind on its surface. Large amounts of solar helium (He), neon (Ne), and argon (Ar) trapped in various depths in the grains were observed, which can be explained by multiple implantations of solar wind particles into the grains, combined with preferential He loss caused by frictional wear of space-weathered rims on the grains. Short residence time of less than 8 million years was implied for the grains by an estimate on cosmic-ray-produced (21)Ne. Our results suggest that Itokawa is continuously losing its surface materials into space at a rate of tens of centimeters per million years. The lifetime of Itokawa should be much shorter than the age of our solar system.
Akira Tsuchiyama,
Masayuki Uesugi,
Takashi Matsushima,
Tatsuhiro Michikami,
Toshihiko Kadono,
Tomoki Nakamura,
Kentaro Uesugi,
Tsukasa Nakano,
Scott A Sandford,
Ryo Noguchi,
Toru Matsumoto,
Junya Matsuno,
Takashi Nagano,
Yuta Imai,
Akihisa Takeuchi,
Yoshio Suzuki,
Toshihiro Ogami,
Jun Katagiri,
Mitsuru Ebihara,
Trevor R Ireland,
Fumio Kitajima,
Keisuke Nagao,
Hiroshi Naraoka,
Takaaki Noguchi,
Ryuji Okazaki,
Hisayoshi Yurimoto,
Michael E Zolensky,
Toshifumi Mukai,
Masanao Abe,
Toru Yada,
Akio Fujimura,
Makoto Yoshikawa,
Junichiro Kawaguchi
Department of Earth and Space Science, Osaka University, Toyonaka, 560-0043, Japan. akira@ess.sci.osaka-u.ac.jp
Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Their three-dimensional (3D) structure and other properties, revealed by x-ray microtomography, provide information on regolith formation. Modal abundances of minerals, bulk density (3.4 grams per cubic centimeter), and the 3D textures indicate that the particles represent a mixture of equilibrated and less-equilibrated LL chondrite materials. Evidence for melting was not seen on any of the particles. Some particles have rounded edges. Overall, the particles' size and shape are different from those seen in particles from the lunar regolith. These features suggest that meteoroid impacts on the asteroid surface primarily form much of the regolith particle, and that seismic-induced grain motion in the smooth terrain abrades them over time.
M Ebihara,
S Sekimoto,
N Shirai,
Y Hamajima,
M Yamamoto,
K Kumagai,
Y Oura,
T R Ireland,
F Kitajima,
K Nagao,
T Nakamura,
H Naraoka,
T Noguchi,
R Okazaki,
A Tsuchiyama,
M Uesugi,
H Yurimoto,
M E Zolensky,
M Abe,
A Fujimura,
T Mukai,
Y Yada
Department of Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan. ebihara-mitsuru@tmu.ac.jp
A single grain (~3 micrograms) returned by the Hayabusa spacecraft was analyzed by neutron activation analysis. This grain is mainly composed of olivine with minor amounts of plagioclase, troilite, and metal. Our results establish that the Itokawa sample has similar chemical characteristics (iron/scandium and nickel/cobalt ratios) to chondrites, confirming that this grain is extraterrestrial in origin and has primitive chemical compositions. Estimated iridium/nickel and iridium/cobalt ratios for metal in the Itokawa samples are about five times lower than CI carbonaceous chondrite values. A similar depletion of iridium was observed in chondrule metals of ordinary chondrites. These metals must have condensed from the nebular where refractory siderophile elements already condensed and were segregated.
Tomoki Nakamura,
Takaaki Noguchi,
Masahiko Tanaka,
Michael E Zolensky,
Makoto Kimura,
Akira Tsuchiyama,
Aiko Nakato,
Toshihiro Ogami,
Hatsumi Ishida,
Masayuki Uesugi,
Toru Yada,
Kei Shirai,
Akio Fujimura,
Ryuji Okazaki,
Scott A Sandford,
Yukihiro Ishibashi,
Masanao Abe,
Tatsuaki Okada,
Munetaka Ueno,
Toshifumi Mukai,
Makoto Yoshikawa,
Junichiro Kawaguchi
Department of Earth and Planetary Material Sciences, Faculty of Science, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan. tomoki@m.tohoku.ac.jp
The Hayabusa spacecraft successfully recovered dust particles from the surface of near-Earth asteroid 25143 Itokawa. Synchrotron-radiation x-ray diffraction and transmission and scanning electron microscope analyses indicate that the mineralogy and mineral chemistry of the Itokawa dust particles are identical to those of thermally metamorphosed LL chondrites, consistent with spectroscopic observations made from Earth and by the Hayabusa spacecraft. Our results directly demonstrate that ordinary chondrites, the most abundant meteorites found on Earth, come from S-type asteroids. Mineral chemistry indicates that the majority of regolith surface particles suffered long-term thermal annealing and subsequent impact shock, suggesting that Itokawa is an asteroid made of reassembled pieces of the interior portions of a once larger asteroid.
Int J Mol Sci. 2011 ;12 (6):3432-44
21747686
Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
A mechanism for creating an enantioenrichment in the amino acids, the building blocks of the proteins, that involves global selection of one handedness by interactions between the amino acids and neutrinos from core-collapse supernovae is defined. The chiral selection involves the dependence of the interaction cross sections on the orientations of the spins of the neutrinos and the (14)N nuclei in the amino acids, or in precursor molecules, which in turn couple to the molecular chirality. It also requires an asymmetric distribution of neutrinos emitted from the supernova. The subsequent chemical evolution and galactic mixing would ultimately populate the Galaxy with the selected species. The resulting amino acids could either be the source thereof on Earth, or could have triggered the chirality that was ultimately achieved for Earth's proteinaceous amino acids.
Department of Astronomy and College of Engineering, 328 Space Sciences Building, Cornell University, Ithaca, New York 14853-6801, USA. jab16@cornell.edu
For 350 years after Galileo's discoveries, ground-based telescopes and theoretical modelling furnished everything we knew about the Sun's planetary retinue. Over the past five decades, however, spacecraft visits to many targets transformed these early notions, revealing the diversity of Solar System bodies and displaying active planetary processes at work. Violent events have punctuated the histories of many planets and satellites, changing them substantially since their birth. Contemporary knowledge has finally allowed testable models of the Solar System's origin to be developed and potential abodes for extraterrestrial life to be explored. Future planetary research should involve focused studies of selected targets, including exoplanets.
Lawrence Livermore National Laboratory, Livermore, California 94551, USA. boyd11@llnl.gov
A mechanism for creating amino acid enantiomerism that always selects the same large-scale chirality is identified, and subsequent chemical replication and galactic mixing that would populate the Galaxy with the predominant species is described. This involves (1) the spin of the 14N in the amino acids, or in precursor molecules from which amino acids might be formed, that couples to the chirality of the molecules;(2) the neutrinos emitted from the supernova, together with the magnetic field from the nascent neutron star or black hole formed from the supernova, which selectively destroy one orientation of the 14N and thus select the chirality associated with the other 14N orientation;(3) chemical evolution, by which the molecules replicate and evolve to more complex forms of a single chirality on a relatively short timescale; and (4) galactic mixing on a longer timescale that mixes the selected molecules throughout the Galaxy.
Science. 2009 Oct 9;326 (5950):275-8
19815773
B E Schmidt,
P C Thomas,
J M Bauer,
J-Y Li,
L A McFadden,
M J Mutchler,
S C Radcliffe,
A S Rivkin,
C T Russell,
J Wm Parker,
S A Stern
Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095, USA. britneys@ucla.edu
We obtained Hubble Space Telescope images of 2 Pallas in September 2007 that reveal distinct color and albedo variations across the surface of this large asteroid. Pallas's shape is an ellipsoid with radii of 291 (+/-9), 278 (+/-9), and 250 (+/-9) kilometers, implying a density of 2400 (+/-250) kilograms per cubic meter-a value consistent with a body that formed from water-rich material. Our observations are consistent with the presence of an impact feature, 240 (+/-25) kilometers in diameter, within Pallas's ultraviolet-dark terrain. Our observations imply that Pallas is an intact protoplanet that has undergone impact excavation and probable internal alteration.
UMR 6202 Cassiopée, University of Nice-Sophia Antipolis, CNRS, Observatoire de la Côte d'Azur, BP 4229, 06304 Nice Cedex 4, France. kwalsh@oca.eu
Asteroids with satellites are observed throughout the Solar System, from subkilometre near-Earth asteroid pairs to systems of large and distant bodies in the Kuiper belt. The smallest and closest systems are found among the near-Earth and small inner main-belt asteroids, which typically have rapidly rotating primaries and close secondaries on circular orbits. About 15 per cent of near-Earth and main-belt asteroids with diameters under 10 km have satellites. The mechanism that forms such similar binaries in these two dynamically different populations was hitherto unclear. Here we show that these binaries are created by the slow spinup of a 'rubble pile' asteroid by means of the thermal YORP (Yarkovsky-O'Keefe-Radzievskii-Paddack) effect. We find that mass shed from the equator of a critically spinning body accretes into a satellite if the material is collisionally dissipative and the primary maintains a low equatorial elongation. The satellite forms mostly from material originating near the primary's surface and enters into a close, low-eccentricity orbit. The properties of binaries produced by our model match those currently observed in the small near-Earth and main-belt asteroid populations, including 1999 KW(4)(refs 3, 4).
Science. 2007 Apr 19;:
17446355
Cit:4
Hideaki Miyamoto,
Hajime Yano,
Daniel J Scheeres,
Shinsuke Abe,
Olivier Barnouin-Jha,
Andrew F Cheng,
Hirohide Demura,
Robert W Gaskell,
Naru Hirata,
Masateru Ishiguro,
Tatsuhiro Michikami,
Akiko M Nakamura,
Ryosuke Nakamura,
Jun Saito,
Sho Sasaki
Department of Museum Collection Utilization Studies, The University Museum, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Earth and Planetary Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Geosystem Engineering, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan; Planetary Science Institute, 1700E Fort Lowell, Suite 106, Tucson AZ 85719, USA.
High-resolution images of the surface of asteroid Itokawa from the Hayabusa mission reveal it to be covered with unconsolidated millimeter-sized and larger gravels. Locations and morphologic characteristics of this gravel indicate that Itokawa has experienced considerable vibrations, which have triggered global-scale granular processes in its dry, vacuum, microgravity environment. These processes likely include granular convection, landslide-like granular migrations, and particle sorting, resulting in the segregation of the fine gravels into areas of potential lows. Granular processes become major resurfacing processes because of Itokawa's small size, implying that they can occur on other small asteroids should they have regolith.
Other papers by authors:
Hajime Yano,
T Kubota,
H Miyamoto,
T Okada,
D Scheeres,
Y Takagi,
K Yoshida,
M Abe,
S Abe,
O Barnouin-Jha,
A Fujiwara,
S Hasegawa,
T Hashimoto,
M Ishiguro,
M Kato,
J Kawaguchi,
T Mukai,
J Saito,
S Sasaki,
M Yoshikawa
Department of Planetary Science, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 Japan. yano@isas.jaxa.jp
After global observations of asteroid 25143 Itokawa by the Hayabusa spacecraft, we selected the smooth terrain of the Muses Sea for two touchdowns carried out on 19 and 25 November 2005 UTC for the first asteroid sample collection with an impact sampling mechanism. Here, we report initial findings about geological features, surface condition, regolith grain size, compositional variation, and constraints on the physical properties of this site by using both scientific and housekeeping data during the descent sequence of the first touchdown. Close-up images revealed the first touchdown site as a regolith field densely filled with size-sorted, millimeter- to centimeter-sized grains.
J Saito,
H Miyamoto,
R Nakamura,
M Ishiguro,
T Michikami,
A M Nakamura,
H Demura,
S Sasaki,
N Hirata,
C Honda,
A Yamamoto,
Y Yokota,
T Fuse,
F Yoshida,
D J Tholen,
R W Gaskell,
T Hashimoto,
T Kubota,
Y Higuchi,
T Nakamura,
P Smith,
K Hiraoka,
T Honda,
S Kobayashi,
M Furuya,
N Matsumoto,
E Nemoto,
A Yukishita,
K Kitazato,
B Dermawan,
A Sogame,
J Terazono,
C Shinohara,
H Akiyama
Hayabusa Project Team, Institute of Space and Astronautical Sciences (ISAS), Japan Aerospace Exploration Agency (JAXA), 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan. saitoj@planeta.sci.isas.jaxa.jp
Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure.
T Noguchi,
T Nakamura,
M Kimura,
M E Zolensky,
M Tanaka,
T Hashimoto,
M Konno,
A Nakato,
T Ogami,
A Fujimura,
M Abe,
T Yada,
T Mukai,
M Ueno,
T Okada,
K Shirai,
Y Ishibashi,
R Okazaki
College of Science, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512, Japan. tngc@mx.ibaraki.ac.jp
The reflectance spectra of the most abundant meteorites, ordinary chondrites, are different from those of the abundant S-type (mnemonic for siliceous) asteroids. This discrepancy has been thought to be due to space weathering, which is an alteration of the surfaces of airless bodies exposed to the space environment. Here we report evidence of space weathering on particles returned from the S-type asteroid 25143 Itokawa by the Hayabusa spacecraft. Surface modification was found in 5 out of 10 particles, which varies depending on mineral species. Sulfur-bearing Fe-rich nanoparticles exist in a thin (5 to 15 nanometers) surface layer on olivine, low-Ca pyroxene, and plagioclase, which is suggestive of vapor deposition. Sulfur-free Fe-rich nanoparticles exist deeper inside (<60 nanometers) ferromagnesian silicates. Their texture suggests formation by metamictization and in situ reduction of Fe(2+).
Pharmacogenomics J. 2011 Sep 13;:
21912425
M Tohkin,
N Kaniwa,
Y Saito,
E Sugiyama,
K Kurose,
J Nishikawa,
R Hasegawa,
M Aihara,
K Matsunaga,
M Abe,
H Furuya,
Y Takahashi,
H Ikeda,
M Muramatsu,
M Ueta,
C Sotozono,
S Kinoshita,
Z Ikezawa
Department of Medicinal Safety Science, National Institute of Health Sciences, Tokyo, Japan.
Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are severe, cutaneous adverse drug reactions that are rare but life threatening. Genetic biomarkers for allopurinol-related SJS/TEN in Japanese were examined in a genome-wide association study in which Japanese patients (n=14) were compared with ethnically matched healthy controls (n=991). Associations between 890 321 single nucleotide polymorphisms and allopurinol-related SJS/TEN were analyzed by the Fisher's exact test (dominant genotype mode). A total of 21 polymorphisms on chromosome 6 were significantly associated with allopurinol-related SJS/TEN. The strongest association was found at rs2734583 in BAT1, rs3094011 in HCP5 and GA005234 in MICC (P=2.44 × 10(-8); odds ratio=66.8; 95% confidence interval, 19.8-225.0). rs9263726 in PSORS1C1, also significantly associated with allopurinol-related SJS/TEN, is in absolute linkage disequilibrium with human leukocyte antigen-B*5801, which is in strong association with allopurinol-induced SJS/TEN. The ease of typing rs9263726 makes it a useful biomarker for allopurinol-related SJS/TEN in Japanese.The Pharmacogenomics Journal advance online publication, 13 September 2011; doi:10.1038/tpj.2011.41.
M Ebihara,
S Sekimoto,
N Shirai,
Y Hamajima,
M Yamamoto,
K Kumagai,
Y Oura,
T R Ireland,
F Kitajima,
K Nagao,
T Nakamura,
H Naraoka,
T Noguchi,
R Okazaki,
A Tsuchiyama,
M Uesugi,
H Yurimoto,
M E Zolensky,
M Abe,
A Fujimura,
T Mukai,
Y Yada
Department of Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan. ebihara-mitsuru@tmu.ac.jp
A single grain (~3 micrograms) returned by the Hayabusa spacecraft was analyzed by neutron activation analysis. This grain is mainly composed of olivine with minor amounts of plagioclase, troilite, and metal. Our results establish that the Itokawa sample has similar chemical characteristics (iron/scandium and nickel/cobalt ratios) to chondrites, confirming that this grain is extraterrestrial in origin and has primitive chemical compositions. Estimated iridium/nickel and iridium/cobalt ratios for metal in the Itokawa samples are about five times lower than CI carbonaceous chondrite values. A similar depletion of iridium was observed in chondrule metals of ordinary chondrites. These metals must have condensed from the nebular where refractory siderophile elements already condensed and were segregated.
M Abe,
Y Takagi,
K Kitazato,
S Abe,
T Hiroi,
F Vilas,
B E Clark,
P A Abell,
S M Lederer,
K S Jarvis,
T Nimura,
Y Ueda,
A Fujiwara
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan.
The near-infrared spectrometer on board the Japanese Hayabusa spacecraft found a variation of more than 10% in albedo and absorption band depth in the surface reflectance of asteroid 25143 Itokawa. Spectral shape over the 1-micrometer absorption band indicates that the surface of this body has an olivine-rich mineral assemblage potentially similar to that of LL5 or LL6 chondrites. Diversity in the physical condition of Itokawa's surface appears to be larger than for other S-type asteroids previously explored by spacecraft, such as 433 Eros.
Pathology Division, National Cancer Center Research Institute East, Kashiwa, Chiba 277-8577, Japan.
Cervical lymph node metastasis is the most common recurrence pattern of head and neck squamous cell carcinoma (HNSCC), and it is usually treated with radiation therapy and/or neck dissection. There has long been a desire for markers useful in predicting radiosensitivity to enable assignment of patients with recurrent head and neck cancer to clinical trials to improve their survival rates and quality of life. A total of 43 cases of HNSCC treated with whole or elective neck irradiation (total dose, 26-70 Gy; median, 60 Gy) for recurrent metastatic SCC in neck lymph nodes after neck dissection between 1992 and 1999 were the subject of this study. The relationship between radiosensitivity and clinicopathological and histopathological factors, including the Ki-67-labeling index for cell proliferation, p53 immunoreactivity and microvessel density (MVD), in surgical neck lymph node specimens were investigated by univariate and multivariate analysis. Of the 43 patients, 31 had recurrent tumors in neck lymph nodes after radiotherapy. Univariate analysis revealed significant associations between radiosensitivity and both high grade of keratinization (p=0.033) and low MVD (p=0.004), and marginally significant associations between radiosensitivity and grade of differentiation of the cancer in the lymph nodes (p=0.070). Multivariate analysis showed that only MVD had predictive value (p=0.016). Tumors with a high MVD possessed a significantly better neck control rate than tumors with a low MVD (p=0.004) by Kaplan-Meier analysis. MVD can be used as a good predictive marker for radiosensitivity of metastatic HNSCCs in cervical lymph nodes after neck dissection.
A F Cheng,
O Barnouin-Jha,
M T Zuber,
J Veverka,
D E Smith,
G A Neumann,
M Robinson,
P Thomas,
J B Garvin,
S Murchie,
C Chapman,
L Prockter
The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA. andrew.cheng@jhuapl.edu
During the Near Earth Asteroid Rendezvous (NEAR)-Shoemaker's low-altitude flyover of asteroid 433 Eros, observations by the NEAR Laser Rangefinder (NLR) have helped to characterize small-scale surface features. On scales from meters to hundreds of meters, the surface has a fractal structure with roughness dominated by blocks, structural features, and walls of small craters. This fractal structure suggests that a single process, possibly impacts, dominates surface morphology on these scales.
T Ariga,
T Kondoh,
K Yamaguchi,
M Yamada,
S Sasaki,
D L Nelson,
H Ikeda,
K Kobayashi,
H Moriuchi,
Y Sakiyama
Department of Human Gene Therapy and Pediatrics, Hokkaido University School of Medicine, Sapporo, Japan. tada-ari@med.hokudai.ac.jp
The Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency disease, arising from mutations of the WAS-protein (WASP) gene. Previously, we have reported that mononuclear cells from WAS patients showed lack/reduced of the intracellular WASP (WASP(dim)) by flow cytometric analysis, and analysis of WASP by flow cytometry (FCM-WASP) was useful for WAS diagnosis. In this study, we report a WAS patient who showed the unique pattern of FCM-WASP. The patient had the small population of normal expression of WASP (WASP(bright)) mononuclear cells together with the major WASP(dim) population. The WASP(bright) cells were detected in T cells, not in B cells or in monocytes. Surprisingly, the molecular studies of the WASP(bright) cells revealed that the inherited mutation of WASP gene was reversed to normal. His mother was proved as a WAS carrier, and HLA studies and microsatellite polymorphic studies proved that the WASP(bright) cells were derived from the patient himself. Therefore, we concluded that the WASP(bright) cells were resulted from spontaneous in vivo reversion of the inherited mutation. Furthermore, the scanning electron microscopic studies indicated that WASP-positive cells from the patient restored the dense microvillus surface projections that were hardly observed in the WASP(dim) cells. This case might have significant implications regarding the prospects of the future gene therapy for WAS patients.
K Tanisada,
T Teshima,
H Ikeda,
M Abe,
J B Owen,
G E Hanks,
T Yamashita,
M Nishio,
S Yamada,
K Sakai,
M Hiraoka,
Y Hirokawa,
M Oguchi,
T Inoue
Department of Medical Engineering, Osaka University Medical School, Suita, Osaka, Japan.
BACKGROUND: The Patterns of Care Study (PCS) was imported to Japan from the United States in July 1996. A preliminary outcome analysis of the PCS for esophageal cancer patients in Japan was made with special reference to age, because the elderly population is rapidly increasing in Japan. PATIENTS AND METHODS: From July 1996 to February 1998, external PCS audits were performed for 37 institutions nationwide and detailed information of 561 esophageal cancer patients treated during the period 1992-1994 was collected by using the fifth PCS data format developed in the United States. This format was provided courtesy of the American College of Radiology. For this study, patients who had not undergone surgery (n = 336) were selected. The patients were classified into three age groups:< 65 years old (n = 119), between 65 and 74 years (n = 93), and 75 years or older (n =123). Cox's proportional hazards model was used for the statistical analysis, with survival, acute/subacute complication and late complication of grade 3 or more based on RTOG criteria, as the endpoints. RESULTS: Significant prognostic factors for the entire non-surgery group were Karnofsky Performance Status (KPS)(p = 0.0007), stage (p = 0.0001), and external irradiation dose (p = 0.0001). For the younger group, KPS (p = 0.0004), stage (p = 0.0197), and utilization of brachytherapy (p = 0.0010) were significant, while for the intermediate age group it was KPS (p = 0. 0027), history of pulmonary disease (p = 0.0339), stage (p = 0.0001), and external dose (p = 0.0001), and for the elderly group, stage (p = 0.0001) and external irradiation dose (p = 0.0224) were significant. Significant risk factors for complications for the entire group were stage (p = 0.0411), external dose (p = 0.0163), and stratification of institution (academic vs. nonacademic)(p = 0. 0114). Significant risk factors for the younger group were history of pulmonary disease (p = 0.0495) and external dose (p = 0.0037), and the other age groups showed no significant risk factors. CONCLUSION: Age was not a significant prognostic or risk factor for esophageal cancer patients in the non-surgery group treated with radiation therapy. Therefore, radiation therapy represented an important treatment modality for the elderly as well as for the younger esophageal cancer patients. External dose was a treatment-related prognostic factor for the elderly as well as for the intermediate age group.
Latest similar papers:
M Pätzold,
T P Andert,
S W Asmar,
J D Anderson,
J-P Barriot,
M K Bird,
B Häusler,
M Hahn,
S Tellmann,
H Sierks,
P Lamy,
B P Weiss
Rheinisches Institut für Umweltforschung, Abteilung Planetenforschung, an der Universität zu Köln, 50931 Cologne, Germany. martin.paetzold@uni-koeln.de
Asteroid 21 Lutetia was approached by the Rosetta spacecraft on 10 July 2010. The additional Doppler shift of the spacecraft radio signals imposed by 21 Lutetia's gravitational perturbation on the flyby trajectory were used to determine the mass of the asteroid. Calibrating and correcting for all Doppler contributions not associated with Lutetia, a least-squares fit to the residual frequency observations from 4 hours before to 6 hours after closest approach yields a mass of (1.700 ± 0.017) × 10(18) kilograms. Using the volume model of Lutetia determined by the Rosetta Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) camera, the bulk density, an important parameter for clues to its composition and interior, is (3.4 ± 0.3) × 10(3) kilograms per cubic meter.
H Sierks,
P Lamy,
C Barbieri,
D Koschny,
H Rickman,
R Rodrigo,
M F A'Hearn,
F Angrilli,
M A Barucci,
J-L Bertaux,
I Bertini,
S Besse,
B Carry,
G Cremonese,
V Da Deppo,
B Davidsson,
S Debei,
M De Cecco,
J De Leon,
F Ferri,
S Fornasier,
M Fulle,
S F Hviid,
R W Gaskell,
O Groussin,
P Gutierrez,
W Ip,
L Jorda,
M Kaasalainen,
H U Keller,
J Knollenberg,
R Kramm,
E Kührt,
M Küppers,
L Lara,
M Lazzarin,
C Leyrat,
J J Lopez Moreno,
S Magrin,
S Marchi,
F Marzari,
M Massironi,
H Michalik,
R Moissl,
G Naletto,
F Preusker,
L Sabau,
W Sabolo,
F Scholten,
C Snodgrass,
N Thomas,
C Tubiana,
P Vernazza,
J-B Vincent,
K-P Wenzel,
T Andert,
M Pätzold,
B P Weiss
Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Strasse 2, 37191 Katlenburg-Lindau, Germany. sierks@mps.mpg.de
Images obtained by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) cameras onboard the Rosetta spacecraft reveal that asteroid 21 Lutetia has a complex geology and one of the highest asteroid densities measured so far, 3.4 ± 0.3 grams per cubic centimeter. The north pole region is covered by a thick layer of regolith, which is seen to flow in major landslides associated with albedo variation. Its geologically complex surface, ancient surface age, and high density suggest that Lutetia is most likely a primordial planetesimal. This contrasts with smaller asteroids visited by previous spacecraft, which are probably shattered bodies, fragments of larger parents, or reaccumulated rubble piles.
Akira Tsuchiyama,
Masayuki Uesugi,
Takashi Matsushima,
Tatsuhiro Michikami,
Toshihiko Kadono,
Tomoki Nakamura,
Kentaro Uesugi,
Tsukasa Nakano,
Scott A Sandford,
Ryo Noguchi,
Toru Matsumoto,
Junya Matsuno,
Takashi Nagano,
Yuta Imai,
Akihisa Takeuchi,
Yoshio Suzuki,
Toshihiro Ogami,
Jun Katagiri,
Mitsuru Ebihara,
Trevor R Ireland,
Fumio Kitajima,
Keisuke Nagao,
Hiroshi Naraoka,
Takaaki Noguchi,
Ryuji Okazaki,
Hisayoshi Yurimoto,
Michael E Zolensky,
Toshifumi Mukai,
Masanao Abe,
Toru Yada,
Akio Fujimura,
Makoto Yoshikawa,
Junichiro Kawaguchi
Department of Earth and Space Science, Osaka University, Toyonaka, 560-0043, Japan. akira@ess.sci.osaka-u.ac.jp
Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Their three-dimensional (3D) structure and other properties, revealed by x-ray microtomography, provide information on regolith formation. Modal abundances of minerals, bulk density (3.4 grams per cubic centimeter), and the 3D textures indicate that the particles represent a mixture of equilibrated and less-equilibrated LL chondrite materials. Evidence for melting was not seen on any of the particles. Some particles have rounded edges. Overall, the particles' size and shape are different from those seen in particles from the lunar regolith. These features suggest that meteoroid impacts on the asteroid surface primarily form much of the regolith particle, and that seismic-induced grain motion in the smooth terrain abrades them over time.
Nano Lett. 2010 Apr 7;:
20373788
Cit:2
Iddo Heller,
Sohail Chatoor,
Jaan Männik,
Marcel A G Zevenbergen,
Jeroen B Oostinga,
Alberto F Morpurgo,
Cees Dekker,
Serge G Lemay
Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
We report an experimental study of 1/f noise in liquid-gated graphene transistors. We show that the gate dependence of the noise is well described by a charge-noise model, whereas Hooge's empirical relation fails to describe the data. At low carrier density, the noise can be attributed to fluctuating charges in close proximity to the graphene, while at high carrier density it is consistent with noise due to scattering in the channel. The charge noise power scales inversely with the device area, and bilayer devices exhibit lower noise than single-layer devices. In air, the observed noise is also consistent with the charge-noise model.
Science. 2009 Oct 9;326 (5950):275-8
19815773
B E Schmidt,
P C Thomas,
J M Bauer,
J-Y Li,
L A McFadden,
M J Mutchler,
S C Radcliffe,
A S Rivkin,
C T Russell,
J Wm Parker,
S A Stern
Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095, USA. britneys@ucla.edu
We obtained Hubble Space Telescope images of 2 Pallas in September 2007 that reveal distinct color and albedo variations across the surface of this large asteroid. Pallas's shape is an ellipsoid with radii of 291 (+/-9), 278 (+/-9), and 250 (+/-9) kilometers, implying a density of 2400 (+/-250) kilograms per cubic meter-a value consistent with a body that formed from water-rich material. Our observations are consistent with the presence of an impact feature, 240 (+/-25) kilometers in diameter, within Pallas's ultraviolet-dark terrain. Our observations imply that Pallas is an intact protoplanet that has undergone impact excavation and probable internal alteration.
This report summarizes U.S. influenza activity since the beginning of the 2007-08 influenza season (September 30, 2007) and updates the previous summary. From September through early December, influenza activity remained low in the United States. Activity increased from early December through the end of the year and has continued to increase in January and February.
R H Tolson,
T C Duxbury,
G H Born,
E J Christensen,
R E Diehl,
D Farless,
C E Hildebrand,
R T Mitchell,
P M Molko,
L A Morabito,
F D Palluconi,
R J Reichert,
H Taraji,
J Veverka,
G Neugebauer,
J T Findlay
During the last 2 weeks of February 1977, an intensive scientific investigation of the martian satellite Phobos was conducted by the Viking Orbiter-1 (VO-1) spacecraft. More than 125 television pictures were obtained during this period and infrared observations were made. About 80 percent of the illuminated hemisphere was imaged at a resolution of about 30 meters. Higher resolution images of limited areas were also obtained. Flyby distances within 80 kilometers of the surface were achieved. An estimate of the mass of Phobos (GM) was obtained by observing the effect of Phobos's gravity on the orbit of VO-1 as sensed by Earth-based radiometric tracking. Preliminary results indicate a value of GM of 0.00066 +/- 0.00012 cubic kilometer per second squared (standard deviation of 3) and a mean density of about 1.9 +/- 0.6 gram per cubic centimeter (standard deviation of 3). This low density, together with the low albedo and the recently determined spectral reflectance, suggest that Phobos is compositionally similar to type I carbonaceous chondrites. Thus, either this object formed in the outer part of the asteroid belt or Lewis's theory that such material cannot condense at 1.5 astronomical units is incorrect. The data on Phobos obtained during this first encounter period are comparable in quantity to all of the data on Mars returned by Mariner flights 4, 6, and 7.
The preparation of highly crystalline polyethylene at low pressures is reported. With careful control of the substrate, the melting and crystallization schedule, and the physical state of the specimen (film thickness), it is possible to prepare polyethylene having a density in excess of 0.999 gram per cubic centimeter, a melting temperature of approximately 140 degrees C, and a heat of fusion in excess of 70 calories per gram. The approach appears to be general and should be applicable to a wide variety of polymers.
Some terrestrial particulate silicate rocks with complex particle shapes have internal friction angles over 45 degrees and cohesion of about 0.1 newton per square centimeter at bulk densities of 0.6 to 0.8 gram per cubic centimeter. Mechanical and other properties of the lunar surface layer, observed with spacecraft, may be consistent with a low bulk density and complex reentrant shapes for the fine particles.
A new allotropic form of water ice with a density of 2.32 +/- 0.15 grams per cubic centimeter has been observed at very low pressures and for temperatures lower than 100 degrees K. It is most likely amorphous.
|
Polish News |
|
||
|
|