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Re-Analysis of HFT Data Using the Apollo Lunar Surface Gravimeter Data
Introduction: The Apollo Passive Seismic Experiment (PSE) was carried out on Apollo 12, 14, 15 and 16. Network observations of four seismic stations were performed for five years from 1972 to 1977. The PSE was a successful mission that informed us of the lunar crustal thickness and seismic velocity structure of the Moon from direct observations of the lunar interior (e.g. [1]). However, the paucity of seismic stations and the limited number of usable seismic events have been a major problem of lunar seismology. An additional observation point enables us to expand the network and the observable area will expand accordingly. Using a data set called the Work Tape, Kawamura et al. (2008) [2] showed that the Lunar Surface Gravimeter (LSG) on Apollo 17 functioned as a seismograph.
With this additional seismic station, we tried the first seismic analysis using the LSG data
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The Lunar Surface Gravimeter as a Lunar Seismograph
Introduction: The primary objective for the Lunar Surface Gravimeter (LSG) on Apollo 17 was to search for gravitational waves, but it failed in detecting them [1]. When the instrument was deployed on the Moon, the sensor beam could not be balanced in the proper equilibrium position. Consequently, the LSG was not able to function as originally designed. Lauderdale and Eichelman (1974) [1] concluded that “no provision has been made to supply data from the experiment to the National Space Science Data Center.” However, it was reported in Giganti et al. (1977) [2] that though they had not detected gravitational waves, after a series of reconfigurations the beam was recentered and the LSG gathered useful data. Besides the observation of gravitational waves, the LSG was also designed to observe seismic signals and tidal deformations [3]. According to Giganti et al. (1977) [2] LSG’s sensitivity covered the frequency range from 1~16Hz (Fig.1). There are several types of moonquakes reported, deep moonquakes, meteorite impacts, and high frequency teleseismic (HFT). Each of the moonquakes is known to have a resonant frequency around 1Hz and in addition, HFT has a predominant frequency around 10 Hz [4]. Therefore it is likely that the LSG was detecting the seismic events on the Moon. However, the LSG data have not been analyzed from a seismological point of view
Primordial Black Hole as a Source of the Boost Factor
Primordial black holes (PBHs) accumulate weakly interacting massive particles
(WIMPs) around them and form ultracompact minihalos (UCMHs), if the WIMP is a
dominant component of the dark matter (DM). In this paper, we discuss that the
UCMHs seeded by the PBHs with sub-earth mass enhance the WIMP annihilation in
the present Universe and can successfully explain the positron and/or electron
excess in cosmic ray observed by PAMELA/Fermi experiments. The signal is very
similar to that from a decaying dark matter, which can explain the PAMELA
and/or Fermi anomaly without conflict with any constraints as long as the decay
mode is proper. In this scenario, the boost factor can be as large as 10^5. In
addition, we discuss testability of our scenario by gamma-ray point source and
gravitational-wave experiments.Comment: 17 pages, 3 figur
Selected topics on parton distribution functions
We report recent studies on structure functions of the nucleon and nuclei.
First, clustering effects are investigated in the structure function F_2 of
Be-9 for explaining an unusual nuclear correction found in a JLab experiment.
We propose that high densities created by formation of clustering structure
like 2*alpha+neutron in Be-9 is the origin of the unexpected JLab result by
using the antisymmetrized molecular dynamics (AMD). There is an approved
proposal at JLab to investigate the structure functions of light nuclei
including the cluster structure, so that much details will become clear in a
few years. Second, tensor-polarized quark and antiquark distributions are
obtained by analyzing HERMES measurements on the structure function b_1 for the
deuteron. The result suggests a finite tensor polarization for antiquark
distributions, which is an interesting topic for further theoretical and
experimental investigations. An experimental proposal exists at JLab for
measuring b_1 of the deuteron as a new tensor-structure study in 2010's.
Furthermore, the antiquark tensor polarization could be measured by polarized
deuteron Drell-Yan processes at hadron facilities such as J-PARC and GSI-FAIR.
Third, the recent CDF dijet anomaly is investigated within the standard model
by considering possible modifications of the strange-quark distribution. We
find that the shape of a dijet-mass spectrum changes depending on the
strange-quark distribution. It indicates that the CDF excess could be partially
explained as a PDF effect, particularly by the strangeness in the nucleon,
within the standard model if the excess at m_{jj}~140 GeV is not a sharp peak.Comment: 8 pages, LaTeX, to be published in AIP proceedings, 8th
Circum-Pan-Pacific Symposium on High Energy Spin Physics, June 20-24, 2011,
Cairns, Australi
ABO-incompatible living-donor pediatric kidney transplantation in Japan
The Japanese ABO-Incompatible Transplantation Committee officially collected and analyzed data on pediatric ABO-incompatible living-donor kidney transplantation in July 2012. The age of a child was defined a
A new type of intra-plate volcanism; young alkali-basalts discovered from the subducting Pacific Plate, northern Japan Trench
How should cardiac xenotransplantation be initiated in Japan?
The version of record of this article, first published in Surgery Today, is available online at Publisher’s website: https://doi.org/10.1007/s00595-024-02861-7.The world's first clinical cardiac xenotransplantation, using a genetically engineered pig heart with 10 gene modifications, prolonged the life of a 57-year-old man with no other life-saving options, by 60 days. It is foreseeable that xenotransplantation will be introduced in clinical practice in the United States. However, little clinical or regulatory progress has been made in the field of xenotransplantation in Japan in recent years. Japan seems to be heading toward a "device lag", and the over-importation of medical devices and technology in the medical field is becoming problematic. In this review, we discuss the concept of pig-heart xenotransplantation, including the pathobiological aspects related to immune rejection, coagulation dysregulation, and detrimental heart overgrowth, as well as genetic modification strategies in pigs to prevent or minimize these problems. Moreover, we summarize the necessity for and current status of xenotransplantation worldwide, and future prospects in Japan, with the aim of initiating xenotransplantation in Japan using genetically modified pigs without a global delay. It is imperative that this study prompts the initiation of preclinical xenotransplantation research using non-human primates and leads to clinical studies
Spectral detection of grazing degradation in the Xilingol Steppe, Inner Mongolia
In order to detect the grazing degradation of steppe vegetation, spectral reflectance was measured using a portable spectral radiometer in the Xilingol steppe, Inner Mongolia. There is only one main drinking place for animals, which is supplied by a water tank at the center of Branch No.4 site-00. In addition to the measurement of surface reflectance, vegetation surveys were carried out involving floristic composition and plant growth parameters as a function of the distance from site-00 at every 1-km interval until the 5-km point. It becomes clear that the effects of grazing on vegetation and soil mitigated according to the distance from site-00. Negative plant indicators of grazing intensity such as Stipa grandis and Filifolium sibiricum increased in dominance with distance from site-00, whereas positive indicators of grazing intensity, such as Cleistogenens squarrosa and Agropyron cristatum, decreased in dominance. Changes in growth parameters along the environmental gradients were reflected on NDVI (Normalized Difference Vegetation Index), in which NDVI was positively correlated with the aboveground biomass (r=0.77, P<0.001), plant height (r=0.69, P<0.001) and coverage (r=0.89, P<0.001), respectively. These results suggested that a spectral vegetation index is effective in the detection of the degradation of grazing grassland in a non-destruction way.Original Pape
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Re-determination of deep moonquake sources using the Apollo 17 lunar surface gravimeter
We performed the first seismic analysis of deep moonquakes using the Apollo 17 Lunar Surface Gravimeter. We redetermined the seismic source of the deep moonquakes and evaluated the contribution of the LSG
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