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1.
Phys Rev Lett ; 131(19): 191001, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-38000434

ABSTRACT

Detailed measurements of the spectral structure of cosmic-ray electrons and positrons from 10.6 GeV to 7.5 TeV are presented from over 7 years of observations with the CALorimetric Electron Telescope (CALET) on the International Space Station. The instrument, consisting of a charge detector, an imaging calorimeter, and a total absorption calorimeter with a total depth of 30 radiation lengths at normal incidence and a fine shower imaging capability, is optimized to measure the all-electron spectrum well into the TeV region. Because of the excellent energy resolution (a few percent above 10 GeV) and the outstanding e/p separation (10^{5}), CALET provides optimal performance for a detailed search of structures in the energy spectrum. The analysis uses data up to the end of 2022, and the statistics of observed electron candidates has increased more than 3 times since the last publication in 2018. By adopting an updated boosted decision tree analysis, a sufficient proton rejection power up to 7.5 TeV is achieved, with a residual proton contamination less than 10%. The observed energy spectrum becomes gradually harder in the lower energy region from around 30 GeV, consistently with AMS-02, but from 300 to 600 GeV it is considerably softer than the spectra measured by DAMPE and Fermi-LAT. At high energies, the spectrum presents a sharp break around 1 TeV, with a spectral index change from -3.15 to -3.91, and a broken power law fitting the data in the energy range from 30 GeV to 4.8 TeV better than a single power law with 6.9 sigma significance, which is compatible with the DAMPE results. The break is consistent with the expected effects of radiation loss during the propagation from distant sources (except the highest energy bin). We have fitted the spectrum with a model consistent with the positron flux measured by AMS-02 below 1 TeV and interpreted the electron+positron spectrum with possible contributions from pulsars and nearby sources. Above 4.8 TeV, a possible contribution from known nearby supernova remnants, including Vela, is addressed by an event-by-event analysis providing a higher proton-rejection power than a purely statistical analysis.

3.
Phys Rev Lett ; 130(21): 211001, 2023 May 26.
Article in English | MEDLINE | ID: mdl-37295105

ABSTRACT

We present the observation of a charge-sign dependent solar modulation of galactic cosmic rays (GCRs) with the Calorimetric Electron Telescope onboard the International Space Station over 6 yr, corresponding to the positive polarity of the solar magnetic field. The observed variation of proton count rate is consistent with the neutron monitor count rate, validating our methods for determining the proton count rate. It is observed by the Calorimetric Electron Telescope that both GCR electron and proton count rates at the same average rigidity vary in anticorrelation with the tilt angle of the heliospheric current sheet, while the amplitude of the variation is significantly larger in the electron count rate than in the proton count rate. We show that this observed charge-sign dependence is reproduced by a numerical "drift model" of the GCR transport in the heliosphere. This is a clear signature of the drift effect on the long-term solar modulation observed with a single detector.


Subject(s)
Cosmic Radiation , Space Flight , Telescopes , Protons , Electrons
4.
Phys Rev Lett ; 130(17): 171002, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37172251

ABSTRACT

We present the results of a direct measurement of the cosmic-ray helium spectrum with the CALET instrument in operation on the International Space Station since 2015. The observation period covered by this analysis spans from October 13, 2015, to April 30, 2022 (2392 days). The very wide dynamic range of CALET allowed for the collection of helium data over a large energy interval, from ∼40 GeV to ∼250 TeV, for the first time with a single instrument in low Earth orbit. The measured spectrum shows evidence of a deviation of the flux from a single power law by more than 8σ with a progressive spectral hardening from a few hundred GeV to a few tens of TeV. This result is consistent with the data reported by space instruments including PAMELA, AMS-02, and DAMPE and balloon instruments including CREAM. At higher energy we report the onset of a softening of the helium spectrum around 30 TeV (total kinetic energy). Though affected by large uncertainties in the highest energy bins, the observation of a flux reduction turns out to be consistent with the most recent results of DAMPE. A double broken power law is found to fit simultaneously both spectral features: the hardening (at lower energy) and the softening (at higher energy). A measurement of the proton to helium flux ratio in the energy range from 60 GeV/n to about 60 TeV/n is also presented, using the CALET proton flux recently updated with higher statistics.

5.
Phys Rev Lett ; 129(10): 101102, 2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36112450

ABSTRACT

A precise measurement of the cosmic-ray proton spectrum with the Calorimetric Electron Telescope (CALET) is presented in the energy interval from 50 GeV to 60 TeV, and the observation of a softening of the spectrum above 10 TeV is reported. The analysis is based on the data collected during ∼6.2 years of smooth operations aboard the International Space Station and covers a broader energy range with respect to the previous proton flux measurement by CALET, with an increase of the available statistics by a factor of ∼2.2. Above a few hundred GeV we confirm our previous observation of a progressive spectral hardening with a higher significance (more than 20 sigma). In the multi-TeV region we observe a second spectral feature with a softening around 10 TeV and a spectral index change from -2.6 to -2.9 consistently, within the errors, with the shape of the spectrum reported by DAMPE. We apply a simultaneous fit of the proton differential spectrum which well reproduces the gradual change of the spectral index encompassing the lower energy power-law regime and the two spectral features observed at higher energies.

6.
Phys Rev Lett ; 128(13): 131103, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35426700

ABSTRACT

The relative abundance of cosmic ray nickel nuclei with respect to iron is by far larger than for all other transiron elements; therefore it provides a favorable opportunity for a low background measurement of its spectrum. Since nickel, as well as iron, is one of the most stable nuclei, the nickel energy spectrum and its relative abundance with respect to iron provide important information to estimate the abundances at the cosmic ray source and to model the Galactic propagation of heavy nuclei. However, only a few direct measurements of cosmic-ray nickel at energy larger than ∼3 GeV/n are available at present in the literature, and they are affected by strong limitations in both energy reach and statistics. In this Letter, we present a measurement of the differential energy spectrum of nickel in the energy range from 8.8 to 240 GeV/n, carried out with unprecedented precision by the Calorimetric Electron Telescope (CALET) in operation on the International Space Station since 2015. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The particle's energy is measured by a homogeneous calorimeter (1.2 proton interaction lengths, 27 radiation lengths) preceded by a thin imaging section (3 radiation lengths) providing tracking and energy sampling. This Letter follows our previous measurement of the iron spectrum [1O. Adriani et al. (CALET Collaboration), Phys. Rev. Lett. 126, 241101 (2021).PRLTAO0031-900710.1103/PhysRevLett.126.241101], and it extends our investigation on the energy dependence of the spectral index of heavy elements. It reports the analysis of nickel data collected from November 2015 to May 2021 and a detailed assessment of the systematic uncertainties. In the region from 20 to 240 GeV/n our present data are compatible within the errors with a single power law with spectral index -2.51±0.07.

7.
Phys Rev Lett ; 129(25): 251103, 2022 Dec 16.
Article in English | MEDLINE | ID: mdl-36608255

ABSTRACT

We present the measurement of the energy dependence of the boron flux in cosmic rays and its ratio to the carbon flux in an energy interval from 8.4 GeV/n to 3.8 TeV/n based on the data collected by the Calorimetric Electron Telescope (CALET) during ∼6.4 yr of operation on the International Space Station. An update of the energy spectrum of carbon is also presented with an increase in statistics over our previous measurement. The observed boron flux shows a spectral hardening at the same transition energy E_{0}∼200 GeV/n of the C spectrum, though B and C fluxes have different energy dependences. The spectral index of the B spectrum is found to be γ=-3.047±0.024 in the interval 25

8.
Phys Rev Lett ; 126(24): 241101, 2021 Jun 18.
Article in English | MEDLINE | ID: mdl-34213922

ABSTRACT

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10 GeV/n to 2.0 TeV/n allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50 GeV/n to 2 TeV/n our present data are compatible with a single power law with spectral index -2.60±0.03.

10.
Phys Rev Lett ; 125(25): 251102, 2020 Dec 18.
Article in English | MEDLINE | ID: mdl-33416351

ABSTRACT

In this paper, we present the measurement of the energy spectra of carbon and oxygen in cosmic rays based on observations with the Calorimetric Electron Telescope on the International Space Station from October 2015 to October 2019. Analysis, including the detailed assessment of systematic uncertainties, and results are reported. The energy spectra are measured in kinetic energy per nucleon from 10 GeV/n to 2.2 TeV/n with an all-calorimetric instrument with a total thickness corresponding to 1.3 nuclear interaction length. The observed carbon and oxygen fluxes show a spectral index change of ∼0.15 around 200 GeV/n established with a significance >3σ. They have the same energy dependence with a constant C/O flux ratio 0.911±0.006 above 25 GeV/n. The spectral hardening is consistent with that measured by AMS-02, but the absolute normalization of the flux is about 27% lower, though in agreement with observations from previous experiments including the PAMELA spectrometer and the calorimetric balloon-borne experiment CREAM.

11.
Dev Biol (Basel) ; 108: 29-39, 2002.
Article in English | MEDLINE | ID: mdl-12220140

ABSTRACT

The first nationwide nucleic acid amplification testing (NAT) for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus type 1 (HIV-1) of voluntarily donated blood after serological pre-screening and before release of cellular components and plasma for fractionation was implemented by the Japanese Red Cross Blood Transfusion Services. The NAT screening assay using multiplex reagent is time-saving, cost effective, and labour-saving procedure for all blood and blood products including short-shelf life platelets. During the 50-mini-pool NAT screening of serologically negative donations (February 1, 2001-April 30, 2001), we were able to screen out 112 HBV-positive, 25 HCV-positive, and 4 HIV-1 positive units from blood and blood components.


Subject(s)
Blood Donors , Blood/virology , HIV-1/isolation & purification , Hepatitis Viruses/isolation & purification , Nucleic Acid Amplification Techniques/methods , Viremia , Blood Transfusion , DNA, Viral , HIV-1/genetics , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis B virus/genetics , Hepatitis B virus/isolation & purification , Hepatitis Viruses/genetics , Humans , Japan , Mass Screening , RNA, Viral/analysis , Red Cross
12.
Gan To Kagaku Ryoho ; 28(11): 1666-8, 2001 Oct.
Article in Japanese | MEDLINE | ID: mdl-11708004

ABSTRACT

Three patients received intraperitoneal chemotherapy of low-dose CDDP for carcinomatous ascites due to gastric and colorectal carcinoma. Intraperitoneal injection of CDDP (30-50 mg) was given and the patients underwent systemic chemotherapy. As a result, the QOL of all patients was improved. Adverse effects of Grade 1 were observed in 1 case (nausea). This intraperitoneal chemotherapy seems to be safe and effective for ascites due to peritonitis carcinomatosa.


Subject(s)
Antineoplastic Agents/administration & dosage , Cisplatin/administration & dosage , Colorectal Neoplasms/complications , Peritonitis/drug therapy , Stomach Neoplasms/complications , Female , Humans , Injections, Intraperitoneal , Male , Middle Aged , Palliative Care , Peritonitis/etiology
13.
Microbiol Immunol ; 45(9): 667-72, 2001.
Article in English | MEDLINE | ID: mdl-11694079

ABSTRACT

The first nationwide nucleic acid amplification testing (NAT) for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus type 1 (HIV-1) of voluntarily donated blood after serological pre-screening and before release of cellular components and plasma for fractionation was implemented by the Japanese Red Cross Blood Transfusion Services. From February 1, 2000 to April 30, 2001, specimens from 6,805,010 units of serologically negative donation were screened in minipools of 50 samples within 24 hr after blood donation by NAT using multiplex HBV/HCV/HIV-1 reagent for blood transfusion including short shelf-life platelets. Among them, 112 HBV DNA-positives, 25 HCV RNA positives and 4 HIV-1 RNA positives were screened out and we could prevent transfusion of these NAT positive units. Subtypes/genotypes of HBV DNA, adr/C, adw/A, adw/B, adw/C, ayr/C and ayw/D were found and adr/C was predominant. A total of 61.6 % of them (69/112) were negative by overnight EIA. Sixth three of HBV NAT-positive samples carried virus loads less than 10(4) copies/mL and 92.1 % of them (58/63) were negative by overnight EIA. The virus growth curves of HBV in 6 cases obtained by retrospective and prospective follow-up study showed exponential straight lines in the early stage of serological window periods and the log times of HBV growth (10 fold increase) in serological window period were between 4.6 and 7.6 days. NAT screening with highly sensitive reagents in pool of specimens is useful to exclude blood units with low level of HBV and HBV mutants from blood transfusion.


Subject(s)
Blood Donors , HIV-1/isolation & purification , Hepacivirus/isolation & purification , Hepatitis B virus/isolation & purification , Mass Screening/methods , Nucleic Acid Amplification Techniques , Genotype , HIV Infections/diagnosis , HIV-1/genetics , Hepacivirus/classification , Hepacivirus/genetics , Hepatitis B/diagnosis , Hepatitis B virus/classification , Hepatitis B virus/genetics , Hepatitis C/diagnosis , Humans , Japan , Male , Nucleic Acids/analysis , Red Cross , Viremia/diagnosis
14.
Zygote ; 7(4): 301-5, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10717948

ABSTRACT

The content of glutathione and other thiols in rat eggs was examined during sperm penetration and pronuclear formation by high-performance liquid chromatography with fluorescence detection. Reduced glutathione (GSH) content was higher in unfertilized oocytes (8.50 +/- 0.29 pmol/egg) and penetrated eggs with a decondensed sperm nucleus (DSH eggs; 7.72 +/- 0.56 pmol/egg) than eggs at the pronuclear stage (PN eggs; 5.93 +/- 0.10 pmol/egg). The content of oxidised glutathione (GSSG) was not different among experimental groups (152.6 +/- 74.1 nmol/egg in unfertilized eggs, 146.0 +/- 50.0 nmol/egg in DSH eggs and 39.7 +/- 17.3 nmol/egg in PN eggs). The GSSG/GSH ratio did not change during fertilization. Although the reduced cysteinylglycine content of eggs did not change among experimental groups, the oxidised form of cysteinylglycine increased (p < 0.025) between sperm decondensation (6.9 +/- 1.5 nmol/egg in unfertilized oocytes and 10.1 +/- 2.1 nmol/egg in DSH eggs) and pronuclear formation (40.5 +/- 11.5 nmol/egg in PN eggs). Low contents of cystine were detected during fertilization but cysteine and gamma-glutamylcysteine were not detected in any treatment groups. These results demonstrate that GSH content in rat eggs decreases between sperm decondensation and pronuclear formation, probably due to the increased activity of gamma-glutamyl transpeptidase.


Subject(s)
Cell Nucleus/metabolism , Glutathione/metabolism , Sulfhydryl Compounds/metabolism , Zygote/metabolism , Animals , Chromatography, High Pressure Liquid , Cysteine/metabolism , Cystine , Dipeptides/metabolism , Fertilization , Fluorescence , Glutathione Disulfide/metabolism , Male , Rats , Rats, Wistar , Spermatozoa/metabolism , gamma-Glutamyltransferase/metabolism
15.
Nihon Kyobu Shikkan Gakkai Zasshi ; 30(9): 1682-6, 1992 Sep.
Article in Japanese | MEDLINE | ID: mdl-1447844

ABSTRACT

Carbohydrate antigen 19-9 (CA19-9) was measured in bronchial lavage fluid in 21 patients with lung cancer and 4 patients with benign lung diseases (2 patients with DPB, 2 patients with BE). Bronchial lavage of the tumor-related bronchus was performed. In normal subjects, levels of CA19-9 in lavage fluid were less than 1000 IU/ml. On the other hand, in 6 patients with lung cancer, levels of CA19-9 were higher than 1000 IU/ml, and in 3 of these cases, CA19-9 levels were higher than 8000 IU/ml. All six three cases were histologically diagnosed as adenocarcinoma. Tumor resected at operation was then stained by antibody recognizing CA19-9. Tumor in cases with high levels of CA19-9 was stained immunohistochemically. These results indicate that measurement of CA19-9 in bronchial lavage fluid of the tumor-related bronchus is a useful auxiliary method in the diagnosis of lung cancer.


Subject(s)
Antigens, Tumor-Associated, Carbohydrate/analysis , Bronchoalveolar Lavage Fluid/immunology , Lung Neoplasms/diagnosis , Adenocarcinoma/diagnosis , Aged , Female , Humans , Immunohistochemistry , Lung Diseases/diagnosis , Male , Middle Aged
16.
Chest ; 102(1): 54-9, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1623796

ABSTRACT

To obtain information on the cellular reactions to Mycobacterium (M) tuberculosis in the lung, we analyzed the cells in bronchoalveolar lavage (BAL) fluid from pulmonary lesions in comparison with those in BAL fluid from nonaffected regions of the lungs, and control lungs, and in peripheral blood of patients with tuberculosis. Neutrophils and lymphocytes were increased in number in BAL fluid from affected lesions of the lungs of patients with miliary tuberculosis and patients with active pulmonary tuberculosis compared with those in BAL fluid from control patients, but the number of alveolar macrophages was decreased in BAL fluid from tuberculous lesions. However, the numbers of these cells were not changed in the BAL fluid from nonaffected regions of the lungs of patients with active or inactive pulmonary tuberculosis. The numbers of lymphocytes were decreased and the numbers of monocytes were increased in peripheral blood from patients with miliary tuberculosis and with active tuberculosis, indicating inverse changes in the numbers of lymphocytes and monocytes in the peripheral blood to those in the BAL fluid of patients with tuberculosis. These results indicate characteristic redistributions of immune or inflammatory cells in response to infection with M tuberculosis and suggest that these changes are important for understanding the pathophysiology of pulmonary tuberculosis.


Subject(s)
Bronchoalveolar Lavage Fluid/immunology , Leukocytes , Macrophages, Alveolar , Tuberculosis, Miliary/immunology , Tuberculosis, Pulmonary/immunology , Adult , Aged , Albumins/analysis , Bronchoalveolar Lavage Fluid/cytology , Cell Count , Child , Eosinophils , Female , Humans , Immunoglobulin G/analysis , Lymphocytes , Male , Middle Aged , Neutrophils , Tuberculosis, Miliary/pathology , Tuberculosis, Pulmonary/pathology
17.
Gan To Kagaku Ryoho ; 14(8): 2532-6, 1987 Aug.
Article in Japanese | MEDLINE | ID: mdl-3039921

ABSTRACT

A phase II evaluation of vindesine (VDS) was performed in 16 patients with non-small cell lung cancer (ten patients with adenocarcinoma, six patients with squamous cell carcinoma, and one patient with large cell carcinoma). All except one of the patients had had prior chemotherapy. VDS at a dose of 3 mg/m2 was given intravenously every week for more than three weeks. Among 16 evaluable patients, two patients with pretreated adenocarcinoma of the lung showed partial response. The response rate for VDS was 12.5%. Toxic effects included leukopenia (94%), anemia (44%), thrombopenia (13%), alopecia (38%), peripheral neurotoxicity (38%), liver injury (19%), constipation (13%), anorexia (13%), nausea (13%), stomatitis (6%) and fever (6%).


Subject(s)
Carcinoma, Small Cell/drug therapy , Lung Neoplasms/drug therapy , Vindesine/therapeutic use , Adult , Aged , Aged, 80 and over , Drug Evaluation , Female , Humans , Male , Middle Aged , Vindesine/administration & dosage , Vindesine/adverse effects
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