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1.
Cancers (Basel) ; 14(10)2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35626162

RESUMEN

Patients with cancer are concerned about the effects of the COVID-19 vaccination. We conducted an online survey on the COVID-19 vaccination status and side effects among patients with cancer in Japan between 8 and 14 August 2021. We included 1182 female patients with cancer aged 20-70 years and registered on an online patient website. Of the patients, 944 had breast cancer, 216 had gynecological cancer, 798 were undergoing drug/radiation therapy, and 370 were in follow-up. At the time of the survey, 885 patients had already received at least one dose. Of these, 580 had also received their second dose. The incidence rate of side effects was equivalent to previous reports. In patients with breast cancer, problems such as the onset or worsening of lymphedema or axillary lymphadenopathy metastasis requiring differential diagnosis were encountered following vaccination. A total of 768 patients were concerned about the vaccine at some point, and 726 consulted with their attending physicians about the timing or side effects of the vaccination. Of the 110 patients undergoing chemotherapy or radiation therapy, 75 adjusted the timing of the vaccination based on their therapy. The cross-analysis revealed that 81% of those who consulted their physician had received at least one dose of the COVID-19 vaccination compared with 65% of those who had not consulted their physician. Consulting with a physician about the COVID-19 vaccination was found to alleviate the concerns of patients with cancer and encourage them to get vaccinated.

2.
Nanomaterials (Basel) ; 12(6)2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35335795

RESUMEN

Nanotechnology has widespread applications in sports; however, there are very few studies reporting the use of nanotechnology to enhance physical performance. We hypothesize that a natural-mineral-based novel nanomaterial, which was developed from Japanese hot springs, might overcome the limitations. We examined if it could enhance physical performance. We conducted a treadmill exercise test on 18 students of athletic clubs at Fukushima University, Japan, and measured heart rate, oxygen consumption, maximal oxygen consumption, CO2 production, and respiratory quotient 106 times in total. The results showed that the elevation of heart rate was significantly suppressed in the natural-mineral-based nanomaterial group, while no differences were observed in oxygen consumption, maximal oxygen consumption, CO2 production, and respiratory quotient between groups. To our knowledge, this result is the first evidence where an improvement of cardiovascular and pulmonary functions was induced by bringing a natural-mineral-based nanomaterial into contact with or close to a living body without pharmacological intervention or physical intervention. This could open new avenue of biomedical industries even in an eco-friendly direction. The precise mechanisms remain a matter for further investigation; however, we may assume that endothelial NO synthase, hemoglobin and endothelium-derived hyperpolarizing factor are deeply involved in the improvement of cardiovascular and pulmonary functions.

3.
Nanomaterials (Basel) ; 10(9)2020 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-32872395

RESUMEN

There are currently no promising therapy strategies for either the treatment or prevention of novel coronavirus disease 2019 (COVID-19), despite the urgent need. In addition to respiratory diseases, vascular complications are rapidly emerging as a key threat of COVID-19. Existing nitric oxide (NO) therapies have been shown to improve the vascular system; however, they have different limitations in terms of safety, usability and availability. In light of this, we hypothesise that a natural-mineral-based novel nanomaterial, which was developed based on NO therapy, might be a viable strategy for the treatment and prevention of COVID-19. The present study examined if it could induce an increase of intravascular NO, vasodilation and the consequent increase of blood flow rate and temperature in a living body. The intravascular NO concentration in the hepatic portal of rats was increased by 0.17 nM over 35.2 s on average after its application. An ultrasonic Doppler flow meter showed significant increases in the blood flow rate and vessel diameter, but no difference in the blood flow velocity. These were corroborated by measurements of human hand surface temperature. To our knowledge, this result is the first evidence where an increase of intravascular NO and vasodilation were induced by bringing a natural-mineral-based nanomaterial into contact with or close to a living body. The precise mechanisms remain a matter for further investigation; however, we may assume that endothelial NO synthase, haemoglobin and endothelium-derived hyperpolarising factor are deeply involved in the increase of intravascular NO.

4.
Sci Rep ; 10(1): 3462, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32103095

RESUMEN

By tuning the physical and chemical pressures of layered perovskite materials we can realize the quantum states of both superconductors and insulators. By reducing the thickness of a layered crystal to a nanometer level, a nanofilm crystal can provide novel quantum states that have not previously been found in bulk crystals. Here we report the realization of high-temperature superconductivity in Ca2RuO4 nanofilm single crystals. Ca2RuO4 thin film with the highest transition temperature Tc (midpoint) of 64 K exhibits zero resistance in electric transport measurements. The superconducting critical current exhibited a logarithmic dependence on temperature and was enhanced by an external magnetic field. Magnetic measurements revealed a ferromagnetic transition at 180 K and diamagnetic magnetization due to superconductivity. Our results suggest the co-appearance of superconductivity and ferromagnetism in Ca2RuO4 nanofilm crystals. We also found that the induced bias current and the tuned film thickness caused a superconductor-insulator transition. The fabrication of micro-nanocrystals made of layered material enables us to discuss rich superconducting phenomena in ruthenates.

5.
ACS Omega ; 3(6): 6151-6157, 2018 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31458798

RESUMEN

Carbon-infiltrated iron ores were prepared from a coal-tar solution and selected calcined iron sources (i.e., goethite (FeOOH) ore, high-grade hematite ore, and Fe2O3 reagent grain). A several hundred micrometer thick carbon layer was deposited on the surface of all iron sources. Because the tar solution successfully penetrated into its nanopores, only goethite ore possessed a significant amount of carbon in its interior nanopores. The carbon-infiltrated ores were heated rapidly in an oxygen atmosphere in the combustion synthesis experiments. Carbon combustion occurred at the ore surface, with the ore temperature increasing suddenly during the experiments. Fast reduction to metallic iron was observed only in the carbon-infiltrated goethite ore, regardless of the oxygen atmosphere. Close contact between the goethite ore and the carbon in its nanoporous interior facilitated the fast reduction. The apparent reduction reaction of goethite ore is akin to a direct reduction reaction (i.e., FeO x + C → FeO x-1 + CO).

6.
Environ Monit Assess ; 190(1): 9, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-29218418

RESUMEN

Water resources are essential for agricultural production in the grain-producing region of China, and water shortage could significantly affect the production and international trade of agricultural products. China is placing effort in new policies to effectively respond to changes in water resources due to changes in land use/land cover as well as climatic variations. This research investigates the changes in land, water, and the awareness of farmer vis-à-vis the implementation of water-saving policies in Zhangye City, an experimental site for pilot programs of water resources management in China. This research indicates that the water saved through water-saving programs and changes in cropping structure (2.2 × 108 m3 a-1) is perhaps lower than the newly increased water withdrawal through corporate-led land reclamation (3.7 × 108 m3 a-1). Most critically, the groundwater withdrawal has increased. In addition, our survey suggests that local government is facing a dilemma of water conservation and agricultural development. Therefore, the enforcement of the ban on farmland reclamation and irrigation water quotas in our study area is revealed to be relatively loose. In this vein, the engagement of local stakeholders in water governance is essential for the future sustainable management of water resources.


Asunto(s)
Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Política Ambiental , Recursos Hídricos/provisión & distribución , Abastecimiento de Agua/estadística & datos numéricos , Agricultura/estadística & datos numéricos , China , Monitoreo del Ambiente , Agricultores , Agua Subterránea , Políticas , Agua
7.
J Occup Health ; 59(6): 506-512, 2017 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-28835575

RESUMEN

OBJECTIVES: Objective measurements using built-in smartphone sensors that can measure physical activity/inactivity in daily working life have the potential to provide a new approach to assessing workers' health effects. The aim of this study was to elucidate the characteristics and reliability of built-in step counting sensors on smartphones for development of an easy-to-use objective measurement tool that can be applied in ergonomics or epidemiological research. METHODS: To evaluate the reliability of step counting sensors embedded in seven major smartphone models, the 6-minute walk test was conducted and the following analyses of sensor precision and accuracy were performed: 1) relationship between actual step count and step count detected by sensors, 2) reliability between smartphones of the same model, and 3) false detection rates when sitting during office work, while riding the subway, and driving. RESULTS: On five of the seven models, the inter-class correlations coefficient (ICC (3,1)) showed high reliability with a range of 0.956-0.993. The other two models, however, had ranges of 0.443-0.504 and the relative error ratios of the sensor-detected step count to the actual step count were ±48.7%-49.4%. The level of agreement between the same models was ICC (3,1): 0.992-0.998. The false detection rates differed between the sitting conditions. CONCLUSIONS: These results suggest the need for appropriate regulation of step counts measured by sensors, through means such as correction or calibration with a predictive model formula, in order to obtain the highly reliable measurement results that are sought in scientific investigation.


Asunto(s)
Acelerometría/métodos , Teléfono Inteligente , Caminata , Acelerometría/normas , Adulto , Análisis de Varianza , Ejercicio Físico , Humanos , Japón , Masculino , Reproducibilidad de los Resultados , Descanso , Conducta Sedentaria , Adulto Joven
8.
Ultramicroscopy ; 175: 97-104, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28183006

RESUMEN

Three-dimensional (3D) distributional analysis of individual dopant atoms in materials is important to development of optical, electronic, and magnetic materials. In this study, we adopted through-focus high-angle annular dark-field (HAADF) imaging for 3D distributional analysis of Eu dopant atoms in Ca-α-SiAlON phosphors. In this context, the effects of convergence semi-angle and Eu z-position on the HAADF image contrast were investigated. Multi-slice image simulation revealed that the contrast of the dopant site was sensitive to change of the defocus level. When the defocus level matched the depth position of a Eu atom, the contrast intensity was significantly increased. The large convergence semi-angle greatly increased the depth resolution because the electron beam tends spread instead of channeling along the atomic columns. Through-focus HAADF-STEM imaging was used to analyze the Eu atom distribution surrounding 10nm cubes with defocus steps of 0.68nm each. The contrast depth profile recorded with a narrow step width clearly analyzed the possible depth positions of Eu atoms. The radial distribution function obtained for the Eu dopants was analyzed using an atomic distribution model that was based on the assumption of random distribution. The result suggested that the Ca concentration did not affect the Eu distribution. The decreased fraction of neighboring Eu atoms along z-direction might be caused by the enhanced short-range Coulomb-like repulsive forces along the z-direction.

9.
Sci Total Environ ; 572: 688-696, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27499498

RESUMEN

One of the most critical challenges in the anthropocentric age is the sustainable management of the planet's increasingly strained water resources. In this avenue, there is a need to advance holistic approaches and objective tools which allow policy makers to better evaluate system-level properties and trade-offs of water resources. This research contributes to the expanding literature in this area by examining the changes to system-level network configurations of the middle reaches of the Heihe River basin from 2000 to 2009. Specifically, through the ecological network analysis (ENA) approach, this research examines changes to the system-level properties of efficiency, redundancy, and evaluates the trade-offs to the resiliency of ecosystem water services of the middle reaches of the Heihe River basin. Our results indicate that while the efficiency of the middle reaches has increased from 2000 to 2009 by 6% and 78% more water is released to the lower reaches, the redundancy of the system has also decreased by 6%. The lower level of redundancy, particularly due to the changes in the groundwater body levels, has critical long-term consequences for the resilience of the water ecosystem services of the middle reaches. In consideration of these holistic trade-offs, two hypothetical alternative scenarios, based on water recycling and saving strategies, are developed to improve the long-term health and resilience of the water system.

10.
Sci Rep ; 5: 9117, 2015 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-25766648

RESUMEN

Latent heat storage using alloys as phase change materials (PCMs) is an attractive option for high-temperature thermal energy storage. Encapsulation of these PCMs is essential for their successful use. However, so far, technology for producing microencapsulated PCMs (MEPCMs) that can be used above 500°C has not been established. Therefore, in this study, we developed Al-Si alloy microsphere MEPCMs covered by α-Al2O3 shells. The MEPCM was prepared in two steps: (1) the formation of an AlOOH shell on the PCM particles using a boehmite treatment, and (2) heat-oxidation treatment in an O2 atmosphere to form a stable α-Al2O3 shell. The MEPCM presented a melting point of 573°C and latent heat of 247 J g(-1). The cycling performance showed good durability. These results indicated the possibility of using MEPCM at high temperatures. The MEPCM developed in this study has great promise in future energy and chemical processes, such as exergy recuperation and process intensification.

11.
Nanotechnology ; 25(13): 135603, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24595235

RESUMEN

This paper describes the facile solution plasma synthesis of bimetallic nanoparticles, including solid solution alloys (Ni-Cu and Ni-Cr system), eutectic alloys of Sn-Pb, and intermetallic alloys (SnSb and Ni3Sn), by using metallic alloy wire as the cathode and Pt wire as the anode. In the typical process, the cathode was melted by the local-concentration of current, upon applying a DC voltage between the two electrodes immersed in the electrolyte. The solid solution alloys of Ni-Cu and Ni-Cr prepared in this study have a uniform distribution of composition. On the other hand, the uniformity in the composition of the eutectic Sn-Pb alloy depends on the microstructure of the electrode. The use of quenched electrode with small crystal grains favors the formation of Sn-Pb alloy nanoparticles, in which the Sn-rich and Pb-rich phases coexist in each particle. The formation of intermetallic SnSb and Ni3Sn alloy nanoparticles is accompanied by the formation of colloidal oxide. These results demonstrate that the solution plasma technique is applicable not only for the synthesis of pure metals but can also be used for the synthesis of various alloy nanoparticles.

12.
Environ Sci Technol ; 45(2): 821-6, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21126038

RESUMEN

This paper describes the reduction of hematite with ammonia for ironmaking, in which the effect of temperature on the products was examined. The results showed that the reduction process began at 430 °C during heating, and with an increase in temperature, the reduction mechanism changed apparently from a direct reduction of ammonia (Fe(2)O(3) + 2NH(3) → 2Fe + N(2) + 3H(2)O) to an indirect reduction via the thermal decomposition of ammonia (2NH(3) → N(2) + 3H(2), Fe(2)O(3) + 3H(2) → 2Fe + 3H(2)O) at temperatures over 530 °C. The final product obtained at 600 and 700 °C was pure metallic iron, in contrast with that formed at 450 °C, that is, a mixture of metallic iron and iron nitride. The results suggest the possibility of using ammonia as a reducing agent for carbonless ironmaking, which is operated at a much lower temperature than 900 °C in conventional coal-based ironmaking.


Asunto(s)
Amoníaco/química , Frío , Compuestos Férricos/química , Tecnología Química Verde/métodos , Metalurgia/métodos , Oxidación-Reducción , Difracción de Rayos X
13.
Phys Chem Chem Phys ; 12(15): 3806-14, 2010 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-20358074

RESUMEN

Monodisperse Pt nanoparticles supported on a graphitized carbon black (GC; 150 m(2) g(-1)), which exhibits higher resistance to carbon corrosion than a conventional high-surface-area carbon black (CB; 800 m(2) g(-1)), were prepared by the nanocapsule method. Three kinds of 50 wt%-Pt loaded catalysts (our nanocapsule Pt/GC, a commercial Pt/GC, and a commercial Pt/CB) were subjected to the durability test by a standard potential step protocol (E = 0.9 V <--> 1.3 V vs. RHE, holding 30 s at each E, 1 min for one cycle) in N(2)-saturated 0.1 M HClO(4) solution at 25 degrees C. The oxygen reduction reaction (ORR) activities at these catalysts were evaluated from the hydrodynamic voltammograms in O(2)-saturated 0.1 M HClO(4) solution at 25 degrees C by the rotating ring-disk electrode technique. The kinetically-controlled mass activities (MA) for the ORR at these catalysts at E = 0.85 to 0.70 V vs. RHE were found to decrease in proportion to log [number of potential step cycles] from 100 to 5000 cycles. It was found that our nanpcapsule Pt/GC showed the highest durability; the time elapsed for the reduction of MA(0.8V) to 700 A g(-1) (ca. 1/2 of the initial MA(0.8V)) at our Pt/GC was 30 and 60 times longer than those for the commercial Pt/GC and Pt/CB, respectively. It was found that the most important factor leading to both high MA and high durability is highly dispersed state of Pt nanoparticles with uniform size over the whole surface of the corrosion-resistant GC support, to which our nanocapsule method has contributed greatly.

14.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 66(1): 15-24, 2010 Jan 20.
Artículo en Japonés | MEDLINE | ID: mdl-20145360

RESUMEN

We proposed a new acquisition method of coronary MDCT achieved by pacing rate resetting and/or propranolol or verapamil injection in patients with a pacemaker. Coronary MDCT was undertaken in 57 patients with a pacemaker (DDD: 51, VVI: 6) and in 2975 patients with sinus rhythm as control using Aquilion 64 (Toshiba). Pacing rate was reset to 60 beats per minute (bpm) in DDD, and spontaneous beats were suppressed by propranolol injection. Pacing rate was reset to 70 bpm in atrial fibrillation with VVI, and spontaneous beats were suppressed by verapamil injection. Coronary MDCT was undertaken using as high a beam pitch (BP) as possible. When spontaneous beats were not suppressed, we selected the optimal gantry speed and BP to get the highest temporal resolution. Image quality makes no significant difference between pacemaker and sinus rhythm. When spontaneous beats were completely suppressed (all pacing), mean radiation dose and acquisition time, respectively, decreased by 33.0% and 35.2% in DDD compared with the method recommended by Heart Navi (by Toshiba), and they decreased by 38.1% and 25.9%, respectively, in VVI compared with the method recommended by Heart Navi. We could not estimate coronary stenosis in the proximal right coronary artery by lead artifacts in 30% of DDD pacemakers. In conclusion, the new method is useful for not only reducing radiation dose and acquisition time, but also for maintaining image quality in patients with a pacemaker.


Asunto(s)
Angiografía Coronaria/métodos , Marcapaso Artificial , Tomografía Computarizada por Rayos X/métodos , Anciano , Artefactos , Femenino , Humanos , Masculino , Propranolol/administración & dosificación , Dosis de Radiación , Verapamilo/administración & dosificación
15.
Environ Sci Technol ; 41(12): 4454-7, 2007 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-17626451

RESUMEN

An innovative environmently friendly hydrolysis process for recycling waste aluminum with the generation of high-pressure hydrogen has been proposed and experimentally validated. The effect of the concentration of sodium hydroxide solution on hydrogen generation rate was the main focus of the study. In the experiments, distilled water and aluminum powder were placed in the pressure-resistance reactor made of Hastelloy, and was compressed to a desired constant water pressure using a liquid pump. The sodium hydroxide solution was supplied by liquid pump with different concentrations (from 1.0 to 5.0 mol/dm3) at a constant flow rate into the reactor by replacing the distilled water, and the rate of hydrogen generated was measured simultaneously. The liquid temperature in the reactor increased due to the exothermic reaction given by Al + OH(-) + 3H2O = 1.5H2 + Al(OH)4(-) + 415.6 kJ. Therefore, a high-pressure hydrogen was generated at room temperature by mixing waste aluminum and sodium hydroxide solution. As the hydrogen compressor used in this process consumes less energy than the conventional one, the generation of hydrogen having a pressure of almost 30 MPa was experimentally validated together with Al(OH)3, a useful byproduct.


Asunto(s)
Aluminio/química , Conservación de los Recursos Naturales , Hidrógeno/química , Administración de Residuos/métodos , Presión , Hidróxido de Sodio/química , Temperatura , Administración de Residuos/instrumentación
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