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1.
Phys Rev Lett ; 132(5): 051002, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364164

RESUMEN

We present the measurement of the cosmic ray proton spectrum from 50 TeV to 1.3 PeV using 7.81×10^{6} extensive air shower events recorded by the ground-based GRAPES-3 experiment between 1 January 2014 and 26 October 2015 with a live time of 460 day. Our measurements provide an overlap with direct observations by satellite and balloon-based experiments. The electromagnetic and muon components in the shower were measured by a dense array of plastic scintillator detectors and a tracking muon telescope, respectively. The relative composition of the proton primary from the air shower data containing all primary particles was extracted using the multiplicity distribution of muons which is a sensitive observable for mass composition. The observed proton spectrum suggests a spectral hardening at ∼166 TeV and disfavors a single power law description of the spectrum up to the Knee energy (∼3 PeV).

3.
NPJ Microgravity ; 9(1): 61, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553360

RESUMEN

Studying the gravity-dependent characteristics of regolith, fine-grained granular media covering extra-terrestrial bodies is essential for the reliable design and analysis of landers and rovers for space exploration. In this study, we propose an experimental approach to examine a granular flow under stable artificial gravity conditions for a long duration generated by a centrifuge at the International Space Station. We also perform a discrete element simulation of the granular flow in both artificial and natural gravity environments. The simulation results verify that the granular flows in artificial and natural gravity are consistent. Further, regression analysis of the experimental results reveals that the mass flow rate of granular flow quantitatively follows a well-known physics-based law with some deviations under low-gravity conditions, implying that the bulk density of the granular media decreases with gravity. This insight also indicates that the bulk density considered in simulation studies of space probes under low-gravity conditions needs to be tuned for their reliable design and analysis.

5.
Nat Commun ; 13(1): 6259, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36307443

RESUMEN

Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA's Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations.

6.
Space Sci Rev ; 218(5): 38, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35757012

RESUMEN

This paper presents the highlights of joint observations of the inner magnetosphere by the Arase spacecraft, the Van Allen Probes spacecraft, and ground-based experiments integrated into spacecraft programs. The concurrent operation of the two missions in 2017-2019 facilitated the separation of the spatial and temporal structures of dynamic phenomena occurring in the inner magnetosphere. Because the orbital inclination angle of Arase is larger than that of Van Allen Probes, Arase collected observations at higher L -shells up to L ∼ 10 . After March 2017, similar variations in plasma and waves were detected by Van Allen Probes and Arase. We describe plasma wave observations at longitudinally separated locations in space and geomagnetically-conjugate locations in space and on the ground. The results of instrument intercalibrations between the two missions are also presented. Arase continued its normal operation after the scientific operation of Van Allen Probes completed in October 2019. The combined Van Allen Probes (2012-2019) and Arase (2017-present) observations will cover a full solar cycle. This will be the first comprehensive long-term observation of the inner magnetosphere and radiation belts.

8.
Rhinology ; 59(6): 511-516, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34726671

RESUMEN

BACKGROUND: Olfaction plays an important role in our daily and social lives, both as adults and as children. This study assessed whether the ability to identify odours increases with age, as well as the ability in various age groups and the factors involved. METHODS: The survey was performed in 2017 on 697 Japanese children (366 girls and 331 boys) aged 6â€"18 years who lived in Tsunan, Niigata Prefecture, Japan by using the 'Open Essence', a card-type odour identification test. We collected information regarding age, sex, and physical characteristic. We also inquired whether participants had siblings or if members of the family smoked, and whether they had conversations about odour at home. Statistical analysis was performed to evaluate the factors affecting odour identification abilities. RESULTS: The results showed that the odour identification abilities of children increase with age, and children who have daily conversations about odours at home have better odour identification abilities. CONCLUSIONS: Odour identification ability increases with age. In addition, our findings suggest that conversation may positively affect odour identification. Hence, it is important for children to be exposed to an environment where they develop an interest in smells for better growth of their olfactory identification ability.


Asunto(s)
Odorantes , Olfato , Adulto , Niño , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
9.
Regul Toxicol Pharmacol ; 125: 105026, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34389358

RESUMEN

Next generation risk assessment (NGRA) is an exposure-led, hypothesis-driven approach that has the potential to support animal-free safety decision-making. However, significant effort is needed to develop and test the in vitro and in silico (computational) approaches that underpin NGRA to enable confident application in a regulatory context. A workshop was held in Montreal in 2019 to discuss where effort needs to be focussed and to agree on the steps needed to ensure safety decisions made on cosmetic ingredients are robust and protective. Workshop participants explored whether NGRA for cosmetic ingredients can be protective of human health, and reviewed examples of NGRA for cosmetic ingredients. From the limited examples available, it is clear that NGRA is still in its infancy, and further case studies are needed to determine whether safety decisions are sufficiently protective and not overly conservative. Seven areas were identified to help progress application of NGRA, including further investments in case studies that elaborate on scenarios frequently encountered by industry and regulators, including those where a 'high risk' conclusion would be expected. These will provide confidence that the tools and approaches can reliably discern differing levels of risk. Furthermore, frameworks to guide performance and reporting should be developed.


Asunto(s)
Alternativas a las Pruebas en Animales/métodos , Seguridad de Productos para el Consumidor/normas , Cosméticos/normas , Medición de Riesgo
10.
Rhinology ; 59(4): 398-401, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34185822

RESUMEN

BACKGROUND: Chronic rhinosinusitis (CRS) is a common disease, and endoscopic sinus surgery (ESS) is widely performed. However, there is no consensus regarding postoperative pain control after ESS, and postoperative opioid abuse is a problem in many countries. Acetaminophen is reportedly effective for postoperative pain control. Preemptive analgesia has received more attention lately, wherein pain is prevented before it occurs. In this study, we assessed the use of acetaminophen for preemptive analgesia during the perioperative period in ESS. METHODOLOGY: This is a retrospective study of 175 patients who underwent ESS, septoplasty, and bilateral inferior turbinate mucosal resection at our hospital from April 2016 to February 2018. In total, 82 patients received 1,000 mg of acetaminophen during surgery and 4 hours after the first dose, while 93 patients did not receive it routinely. We compared these two groups. The primary outcome was the need to use additional analgesics prescribed by the ward physician and the secondary outcomes included postoperative pain, postoperative bleeding, reoperation, blood pressure, and body temperature. RESULTS: The use of additional oral and intravenous analgesics was significantly reduced in the patients who received acetaminophen perioperatively. CONCLUSION: Preemptive analgesia during the perioperative period of ESS could lead to satisfactory postoperative pain control.


Asunto(s)
Analgesia , Analgésicos Opioides , Acetaminofén , Humanos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Estudios Retrospectivos
11.
Clin Exp Immunol ; 202(1): 119-135, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32562271

RESUMEN

Heparin is a widely used anti-coagulant that enhances anti-thrombin (AT) activity. However, heparin also suppresses immune and inflammatory responses in various rodent models and clinical trials, respectively. The mechanism by which heparin suppresses immune responses is unclear. The effect of heparin on regulatory T cells (Tregs ) in allogeneic immune responses was analysed using an acute graft-versus-host disease (aGVHD) mouse model and mixed lymphocyte reactions (MLRs). In-vitro culture systems were utilized to study the effects of heparin on Tregs . Heparin administration reduced mortality rates and increased the proportion of Tregs in the early post-transplantation period of aGVHD mice. In both murine and human MLRs, heparin increased Tregs and inhibited responder T cell proliferation. Heparin promoted functional CD4+ CD25+ forkhead box protein 3 (FoxP3)+ Treg generation from naive CD4+ T cells, increased interleukin (IL)-2 production and enhanced the activation of pre-existing Tregs with IL-2. Heparin-induced Treg increases were not associated with anti-coagulant activity through AT, but required negatively charged sulphation of heparin. Importantly, N-acetyl heparin, a chemically modified heparin without anti-coagulant activity, induced Tregs and decreased mortality in aGVHD mice. Our results indicate that heparin contributes to Treg -mediated immunosuppression through IL-2 production and suggest that heparin derivatives may be useful for immunopathological control by efficient Treg induction.


Asunto(s)
Anticoagulantes/farmacología , Coagulación Sanguínea , Fibrinolíticos/farmacología , Enfermedad Injerto contra Huésped/inmunología , Linfocitos T Reguladores/inmunología , Animales , Anticoagulantes/efectos adversos , Coagulación Sanguínea/efectos de los fármacos , Coagulación Sanguínea/inmunología , Modelos Animales de Enfermedad , Fibrinolíticos/efectos adversos , Heparina , Ratones , Ratones Endogámicos BALB C , Linfocitos T Reguladores/patología
12.
Phys Rev Lett ; 122(10): 105101, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30932668

RESUMEN

The GRAPES-3 muon telescope located in Ooty, India records rapid (∼10 min) variations in the muon intensity during major thunderstorms. Out of a total of 184 thunderstorms recorded during the interval of April 2011-December 2014, the one on December 1, 2014 produced a massive potential of 1.3 GV. The electric field measured by four well-separated (up to 6 km) monitors on the ground was used to help estimate some of the properties of this thundercloud, including its altitude and area that were found to be 11.4 km above mean sea level and ≥380 km^{2}, respectively. A charging time of 6 min to reach 1.3 GV implied the delivery of a power of ≥2 GW by this thundercloud that was moving at a speed of ∼60 km h^{-1}. This work possibly provides the first direct evidence for the generation of gigavolt potentials in thunderclouds that could also possibly explain the production of highest-energy (100 MeV) gamma rays in the terrestrial gamma-ray flashes.

13.
Cytopathology ; 29(3): 262-266, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29578263

RESUMEN

BACKGROUND: Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens. METHODS: Aspiration samples (n = 41) were smeared on glass slides and used for FISH. RESULTS: Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound-guided FNA samples from the pancreas (n = 18). CONCLUSIONS: The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.


Asunto(s)
Telómero/genética , Ascitis/genética , Ascitis/patología , Inestabilidad Cromosómica/genética , Fluorescencia , Humanos , Hibridación Fluorescente in Situ/métodos , Páncreas/patología , Derrame Pleural/genética , Derrame Pleural/patología
14.
Arch Toxicol ; 92(2): 611-617, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29127450

RESUMEN

Skin sensitisation is the regulatory endpoint that has been at the centre of concerted efforts to replace animal testing in recent years, as demonstrated by the Organisation for Economic Co-operation and Development (OECD) adoption of five non-animal methods addressing mechanisms under the first three key events of the skin sensitisation adverse outcome pathway. Nevertheless, the currently adopted methods, when used in isolation, are not sufficient to fulfil regulatory requirements on the skin sensitisation potential and potency of chemicals comparable to that provided by the regulatory animal tests. For this reason, a number of defined approaches integrating data from these methods with other relevant information have been proposed and documented by the OECD. With the aim to further enhance regulatory consideration and adoption of defined approaches, the European Union Reference Laboratory for Alternatives to Animal testing in collaboration with the International Cooperation on Alternative Test Methods hosted, on 4-5 October 2016, a workshop on the international regulatory applicability and acceptance of alternative non-animal approaches, i.e., defined approaches, to skin sensitisation assessment of chemicals used in a variety of sectors. The workshop convened representatives from more than 20 regulatory authorities from the European Union, United States, Canada, Japan, South Korea, Brazil and China. There was a general consensus among the workshop participants that to maximise global regulatory acceptance of data generated with defined approaches, international harmonisation and standardisation are needed. Potential assessment criteria were defined for a systematic evaluation of existing defined approaches that would facilitate their translation into international standards, e.g., into a performance-based Test Guideline. Informed by the discussions at the workshop, the ICATM members propose practical ways to further promote the regulatory use and facilitate adoption of defined approaches for skin sensitisation assessments.


Asunto(s)
Alternativas a las Pruebas en Animales/normas , Pruebas Cutáneas/normas , Pruebas de Toxicidad/normas , Cooperación Internacional , Estándares de Referencia
15.
Toxicol In Vitro ; 45(Pt 1): 19-24, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28765095

RESUMEN

The bovine corneal opacity and permeability (BCOP) assay is an alternative to the Draize test in rabbits. Although it can be used to evaluate ocular non-irritants and severe irritants, it is not used for the assessment of mild-irritating substances. In this assay, a chemical with an in vitro irritancy score (IVIS)≤3 is defined as a "non-irritant" while one with an IVIS>55 is defined as a "corrosive" or "severe irritant." We attempted to evaluate mild eye irritants by assessing the recovery of corneal lesions histopathologically. Our results indicated that chemicals with IVIS≤6 may be defined as "non-irritants," because the rapid recovery of lesions limited to the squamous layer was predicted by the histopathology. In cases where lesions extended to the wing and basal cell layers, when some intact basal cells remained, the lesions were also predicted to be reversible. Thus, chemicals which induce lesions in which basal cells remain intact can be considered to be mild irritants.


Asunto(s)
Alternativas a las Pruebas en Animales/métodos , Bioensayo/métodos , Bovinos , Córnea/efectos de los fármacos , Opacidad de la Córnea/inducido químicamente , Irritantes/toxicidad , Animales , Opacidad de la Córnea/patología , Cosméticos/toxicidad , Permeabilidad
16.
BMC Cancer ; 17(1): 314, 2017 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-28476132

RESUMEN

BACKGROUND: Recent preclinical and phase I studies have reported that rebamipide decreased the severity of chemoradiotherapy-induced oral mucositis in patients with oral cancer. This placebo-controlled randomized phase II study assessed the clinical benefit of rebamipide in reducing the incidence of severe chemoradiotherapy-induced oral mucositis in patients with head and neck cancer (HNC). METHODS: Patients aged 20-75 years with HNC who were scheduled to receive chemoradiotherapy were enrolled. Patients were randomized to receive rebamipide 2% liquid, rebamipide 4% liquid, or placebo. The primary endpoint was the incidence of grade ≥ 3 oral mucositis determined by clinical examination and assessed by central review according to the Common Terminology Criteria of Adverse Events version 3.0. Secondary endpoints were the time to onset of grade ≥ 3 oral mucositis and the incidence of functional impairment (grade ≥ 3) based on the evaluation by the Oral Mucositis Evaluation Committee. RESULTS: From April 2014 to August 2015, 97 patients with HNC were enrolled, of whom 94 received treatment. The incidence of grade ≥ 3 oral mucositis was 29% and 25% in the rebamipide 2% and 4% groups, respectively, compared with 39% in the placebo group. The proportion of patients who did not develop grade ≥ 3 oral mucositis by day 50 of treatment was 57.9% in the placebo group, whereas the proportion was 68.0% in the rebamipide 2% group and 71.3% in the rebamipide 4% group. The incidences of adverse events potentially related to the study drug were 16%, 26%, and 13% in the placebo, rebamipide 2%, and rebamipide 4% groups, respectively. There was no significant difference in treatment compliance among the groups. CONCLUSIONS: The present phase II study suggests that mouth washing with rebamipide may be effective and safe for patients with HNC receiving chemoradiotherapy, and 4% liquid is the optimal dose of rebamipide. TRIAL REGISTRATION: ClinicalTrials.gov under the identifier NCT02085460 (the date of trial registration: March 11, 2014).


Asunto(s)
Alanina/análogos & derivados , Quimioradioterapia/efectos adversos , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Quinolonas/administración & dosificación , Estomatitis/tratamiento farmacológico , Adulto , Anciano , Alanina/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Estomatitis/inducido químicamente , Estomatitis/patología
18.
Allergy ; 72(6): 918-926, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27873335

RESUMEN

BACKGROUND: Booklice, belonging to the order Psocoptera, are small household insect pests that are distributed worldwide. Liposcelis bostrychophila, a common home-inhabiting species of booklouse, infests old books, sheets of paper, and stored food. Recent entomological and serological studies demonstrated that L. bostrychophila accounted for the majority of detectable insects in house dust and could be a potent inducer of respiratory allergy. Our recent proteomic analysis identified a potent allergenic protein from L. bostrychophila, designated Lip b 1, and determined its partial amino acid sequences. METHODS: Cloning of cDNAs for Lip b 1 was performed by large-scale transcriptome analysis (RNA-seq) and subsequent reverse transcription polymerase chain reaction. The full-length amino acid sequences deduced from Lip b 1 cDNAs were bioinformatically analyzed. The recombinant proteins of glutathione S-transferase (GST)-fused Lip b 1 were analyzed by Western blot and enzyme-linked immunosorbent assay. RESULTS: Lip b 1 cDNAs encoding two types of 254-amino acid proteins were cloned. The clones shared 87% identity, and the deduced molecular weights and isoelectric points were consistent with those determined in our previous study. The two types of Lip b 1 proteins in the GST-fused form were similarly reactive with sera from allergic patients sensitized with L. bostrychophila. CONCLUSIONS: Lip b 1 is a novel protein possibly causing booklouse allergy.


Asunto(s)
Alérgenos/aislamiento & purificación , Proteínas de Insectos/aislamiento & purificación , Phthiraptera/inmunología , Alérgenos/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario , Humanos , Hipersensibilidad/etiología , Proteínas de Insectos/genética , Proteínas de Insectos/inmunología , Phthiraptera/química
19.
Phys Rev Lett ; 117(17): 171101, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27824449

RESUMEN

The GRAPES-3 tracking muon telescope in Ooty, India measures muon intensity at high cutoff rigidities (15-24 GV) along nine independent directions covering 2.3 sr. The arrival of a coronal mass ejection on 22 June 2015 18:40 UT had triggered a severe G4-class geomagnetic storm (storm). Starting 19:00 UT, the GRAPES-3 muon telescope recorded a 2 h high-energy (∼20 GeV) burst of galactic cosmic rays (GCRs) that was strongly correlated with a 40 nT surge in the interplanetary magnetic field (IMF). Simulations have shown that a large (17×) compression of the IMF to 680 nT, followed by reconnection with the geomagnetic field (GMF) leading to lower cutoff rigidities could generate this burst. Here, 680 nT represents a short-term change in GMF around Earth, averaged over 7 times its volume. The GCRs, due to lowering of cutoff rigidities, were deflected from Earth's day side by ∼210° in longitude, offering a natural explanation of its night-time detection by the GRAPES-3. The simultaneous occurrence of the burst in all nine directions suggests its origin close to Earth. It also indicates a transient weakening of Earth's magnetic shield, and may hold clues for a better understanding of future superstorms that could cripple modern technological infrastructure on Earth, and endanger the lives of the astronauts in space.

20.
B-ENT ; 12(4): 279-284, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29709131

RESUMEN

Airway intervention in cases of acute epiglottitis.Problem/objectives: In cases of acute epiglottitis, indications for airway intervention have not been established. In the present study, we reviewed patients with acute epiglottitis to identify clinical factors, which suggest airway intervention should be performed. METHODOLOGY: Patients with acute epiglottitis admitted to The Jikei University Daisan Hospital (Tokyo) from 2004 to 2013 were identified. Patients' characteristics, histories, laryngoscopic findings and laboratory findings were reviewed and analysed. RESULTS: Of the 83 patients (82 adults and one adolescent) in the sample, 16 (19%) underwent airway intervention and conservative treatment. The factors that were significantly more likely to have been present in patients who received airway intervention were odynophagia, drooling, hoarseness, muffled voice, dyspnoea, swelling of the posterior side of the epiglottis, less than 50% of the glottis area being visible with laryngoscopy, and a high white blood cell (WBC) count. The only factor that was shown by multiple logistic regression analysis to be distinctively predictive of airway intervention was "less than 50% of the glottis area being visible" (P = .000, odds ratio = 23.630, sensitivity = 86.6%, specificity = 78.6%, predictive accuracy = 85.2%). CONCLUSIONS: When considering whether airway intervention should be performed in cases of acute epiglottitis, the most important clinical factor is the laryngoscopic finding that "less than 50% of the glottis area being visible." Other important clinical factors to consider are odynophagia, drooling, hoarseness, muffled voice, dyspnoea, swelling of the posterior side of the epiglottis and a high WBC count.


Asunto(s)
Manejo de la Vía Aérea , Epiglotitis/terapia , Enfermedad Aguda , Femenino , Humanos , Laringoscopía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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