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1.
Occup Ther Health Care ; 36(4): 422-439, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34865607

RESUMEN

This study investigated whether dual tasks comprising cognitive tasks and occupations related to daily living can improve the mental and cognitive function of Japanese community-dwelling older adults. Participants included 30 older adults, equally divided into intervention and control groups. The outcome measures were memory, attention, depression, and health-related quality of life. No adverse effects of the intervention were observed in any participant in the intervention group. Logical memory I, logical memory II, and Center for Epidemiologic Studies Depression Scale scores showed a significant interaction. Dual tasks combining cognitive tasks and occupations may help improve delayed recall and alleviate depression. A novel attempt to integrate cognitive stimulation and activities valued by individuals may help mediate age-related cognitive function decline and reduce depressive symptoms in community-dwelling older adults.


Asunto(s)
Vida Independiente , Terapia Ocupacional , Anciano , Cognición/fisiología , Humanos , Japón , Ocupaciones , Proyectos Piloto , Calidad de Vida
2.
Opt Express ; 27(13): 17868-17875, 2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31252739

RESUMEN

We demonstrated a bi-directional, Er-doped dual comb fiber laser consisting of all-polarization-maintaining fiber devices. Polyimide films in which single-wall carbon nanotubes (SWNTs) were dispersed were used as the in-line saturable absorber. In order to avoid synchronization of the two combs and associated damage to the SWNT film, a two-branch configuration with two SWNT films was employed. Soliton pulses with almost the same optical spectra were generated stably in each direction, and dual comb beats were observed simply by overlapping the two outputs. The repetition frequency was 28 MHz, and the frequency difference was 105-140 Hz. Thanks to the small frequency difference, dual comb beats corresponding to the whole optical spectrum were observed without any overlapping. Fourier transform spectroscopy using the developed dual comb source was examined, and the characteristics of an optical filter were successfully obtained.

3.
Opt Lett ; 37(24): 5079-81, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-23258011

RESUMEN

A high-power, passively mode-locked, Er-doped fiber laser with a single wall carbon nanotube polyimide film was demonstrated in dispersion-managed dissipative-soliton mode-locking operation. The average maximum power of 285 mW and a pulse energy of 8.1 nJ are the highest values yet achieved for single-pulse operation in a nanotube fiber laser. A high-power ultrashort pulse of 680 fs was generated by dispersion compensation at a repetition rate of 34.9 MHz. Passive mode-locking was numerically analyzed, and the dynamics and output properties are discussed.

4.
Water Sci Technol ; 66(4): 775-82, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22766866

RESUMEN

In order to evaluate the removal performance of trace phenolic endocrine-disrupting chemicals (EDCs) by aquatic plants, batch and continuous experiments were conducted using floating and submerged plants. The EDCs used in this study were bisphenol A, 2,4-dichlorophenol, 4-tert-octylphenol, pentachlorophenol, and nonylphenol. The feed concentration of each EDC was set at 100 µg/L. Continuous experiments showed that every EDC except pentachlorophenol was efficiently removed by different aquatic plants through the following reaction, catalyzed by peroxidases: EDCs+H(2)O(2)→Products+H(2)O(2). Peroxidases were able to remove phenolic EDCs in the presence of H(2)O(2) over a wide pH range (from 3 to 9). Histochemical localization of peroxidases showed that they were located in every part of the root cells, while highly concentrated zones were observed in the epidermis and in the vascular tissues. Although pentachlorophenol was not removed in the continuous treatment, it was rapidly removed by different aquatic plants when Fe(2+) was added, and this removal occurred simultaneously with the consumption of endogenous H(2)O(2). These results demonstrated the occurrence of a biological Fenton reaction and the importance of H(2)O(2) as a key endogenous substance in the treatment of EDCs and refractory toxic pollutants.


Asunto(s)
Embryophyta/metabolismo , Disruptores Endocrinos/metabolismo , Fenoles/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Peróxido de Hidrógeno/metabolismo , Peroxidasas
5.
Biochemistry ; 50(11): 1778-87, 2011 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-21265508

RESUMEN

Wheat leaves contain two isoproteins of the photosynthetic ferredoxin:NADP(+) reductase (pFNRI and pFNRII). Truncated forms of both enzymes have been detected in vivo, but only pFNRII displays N-terminal length-dependent changes in activity. To investigate the impact of N-terminal truncation on interaction with ferredoxin (Fd), recombinant pFNRII proteins, differing by deletions of up to 25 amino acids, were generated. During purification of the isoproteins found in vivo, the longer forms of pFNRII bound more strongly to a Fd affinity column than did the shorter forms, pFNRII(ISKK) and pFNRII[N-2](KKQD). Further truncation of the N-termini resulted in a pFNRII protein which failed to bind to a Fd column. Similar k(cat) values (104-140 s(-1)) for cytochrome c reduction were measured for all but the most truncated pFNRII[N-5](DEGV), which had a k(cat) of 38 s(-1). Stopped-flow kinetic studies, examining the impact of truncation on electron flow between mutant pFNRII proteins and Fd, showed there was a variation in k(obs) from 76 to 265 s(-1) dependent on the pFNRII partner. To analyze the sites which contribute to Fd binding at the pFNRII N-terminal, three mutants were generated, in which a single or double lysine residue was changed to glutamine within the in vivo N-terminal truncation region. The mutations affected binding of pFNRII to the Fd column. Based on activity measurements, the double lysine residue change resulted in a pFNRII enzyme with decreased Fd affinity. The results highlight the importance of this flexible N-terminal region of the pFNRII protein in binding the Fd partner.


Asunto(s)
Ferredoxina-NADP Reductasa/química , Ferredoxina-NADP Reductasa/metabolismo , Ferredoxinas/química , Hojas de la Planta/enzimología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Triticum/enzimología , Sitios de Unión , Ferredoxina-NADP Reductasa/genética , Ferredoxinas/metabolismo , Cinética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Triticum/metabolismo
6.
Opt Express ; 19(22): 21874-9, 2011 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-22109039

RESUMEN

We investigated a dispersion-managed, passively mode-locked, ultrashort-pulse, Er-doped fiber laser using a polyimide film containing dispersed single-wall carbon nanotubes (SWNTs) and examined the dependence on net cavity dispersion and output coupling ratio using normal-dispersion fibers and a variable output coupler. For the dissipative soliton mode-locking condition, we achieved a pulse energy of 3.5 nJ and an average power of 114 mW, the highest values yet reported for an SWNT fiber laser under single-pulse operation.

7.
J Exp Med ; 189(5): 821-9, 1999 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10049946

RESUMEN

The initiation of an immune response is critically dependent on the activation of dendritic cells (DCs). This process is triggered by surface receptors specific for inflammatory cytokines or for conserved patterns characteristic of infectious agents. Here we show that human DCs are activated by influenza virus infection and by double-stranded (ds)RNA. This activation results not only in increased antigen presentation and T cell stimulatory capacity, but also in resistance to the cytopathic effect of the virus, mediated by the production of type I interferon, and upregulation of MxA. Because dsRNA stimulates both maturation and resistance, DCs can serve as altruistic antigen-presenting cells capable of sustaining viral antigen production while acquiring the capacity to trigger naive T cells and drive polarized T helper cell type 1 responses.


Asunto(s)
Células Dendríticas/inmunología , Proteínas de Unión al GTP , Orthomyxoviridae/inmunología , ARN Bicatenario/inmunología , Presentación de Antígeno , Antivirales/biosíntesis , Comunicación Autocrina , Efecto Citopatogénico Viral , Células Dendríticas/virología , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Interferón-alfa/biosíntesis , Activación de Linfocitos , Complejo Mayor de Histocompatibilidad/inmunología , Proteínas de Resistencia a Mixovirus , Péptidos/inmunología , Biosíntesis de Proteínas , Linfocitos T/inmunología , Células TH1/inmunología
8.
Opt Express ; 18(20): 20673-80, 2010 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-20940963

RESUMEN

An ultralow-repetition-rate, all-polarization-maintaining (PM), Er-doped, ultrashort-pulse fiber laser was demonstrated using a single-wall-carbon-nanotube polyimide film. Using a ring cavity configuration, output pulses with pulse energy of 0.7-2.6 nJ were obtained at an ultralow repetition rate of 943-154 kHz for a fiber length of 0.1-1.3 km. A novel θ (theta) cavity configuration was proposed, which enabled us to reduce the required fiber length by half. A repetition rate of 132 kHz was achieved using this configuration with 909 m of PM fiber.

9.
Water Sci Technol ; 62(10): 2218-24, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21076206

RESUMEN

Continuous treatments of trace endocrine disrupting chemicals (EDCs) such as 17ß-estradiol (E2), bisphenol-A, nonylephenol, 4-t-octyl phenol and pentachlorophenol were carried out using a granular bed electrolytic reactor. Experimental results showed that the EDCs were removed by the reactor over 150 days and removal efficiencies were nearly the same in the presence and absence of humic substance. Energy consumption for the treatment was around several Wh/m(3). For longer operation or higher loading conditions, Fenton oxidation was effective to regenerate electrodes. Calculated results by a mathematical model developed assuming liquid film mass-transfer as a rate-limiting step were in good agreement with observed results. Based on the model, enhancement of reactor performance was discussed.


Asunto(s)
Técnicas Electroquímicas , Disruptores Endocrinos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Reactores Biológicos , Electrodos , Modelos Teóricos , Eliminación de Residuos Líquidos/instrumentación , Eliminación de Residuos Líquidos/métodos
10.
Opt Express ; 17(22): 20233-41, 2009 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-19997248

RESUMEN

A high-energy, wavelength-tunable, all-polarization-maintaining Er-doped ultrashort fiber laser was demonstrated using a polyimide film dispersed with single-wall carbon nanotubes. A variable output coupler and wavelength filter were used in the cavity configuration, and high-power operation was demonstrated. The maximum average power was 12.6 mW and pulse energy was 585 pJ for stable single-pulse operation with an output coupling ratio as high as 98.3%. Wide wavelength-tunable operation at 1532-1562 nm was also demonstrated by controlling the wavelength filter. The RF amplitude noise characteristics were examined in terms of their dependence on output coupling ratio and oscillation wavelength.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Láseres de Estado Sólido , Rayos Láser , Membranas Artificiales , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestructura , Resinas Sintéticas/química , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Refractometría/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Science ; 283(5402): 680-2, 1999 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-9924026

RESUMEN

Although dispensable, costimulation through CD28 facilitates activation of naïve T lymphocytes. CD28 engagement led to the redistribution and clustering of membrane and intracellular kinase-rich raft microdomains at the site of T cell receptor (TCR) engagements. Although not affecting TCR down-regulation, this process led to higher and more stable tyrosine phosphorylation of several substrates and higher consumption of Lck. These results may provide a general mechanism for amplifying receptor signaling by reorganization of membrane microdomains.


Asunto(s)
Antígenos CD28/metabolismo , Activación de Linfocitos , Lípidos de la Membrana/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Células Presentadoras de Antígenos/inmunología , Antígenos CD28/inmunología , Complejo CD3/inmunología , Membrana Celular/metabolismo , Gangliósido G(M1)/metabolismo , Humanos , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Fosforilación , Fosfotirosina/metabolismo , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal , Linfocitos T/metabolismo
12.
Opt Express ; 16(13): 9429-35, 2008 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-18575508

RESUMEN

We present an all-polarization-maintaining Er-doped ultrashort-pulse fiber laser using a single-wall carbon nanotube polyimide nanocomposite saturable absorber. The maximum average power for single-pulse operation is 4.8 mW, and the repetition frequency is 41.3 MHz. Self-start and stable mode-locking operation is achieved. The RF amplitude noise is also examined and it is confirmed that the noise figure is as low as that of a solid-state laser. Using a polarization-maintaining anomalous dispersive fiber, a 314 fs output pulse is compressed to 107 fs via higher-order soliton compression. The peak power of the compressed pulse is up to 1.1 kW.


Asunto(s)
Amplificadores Electrónicos , Tecnología de Fibra Óptica/instrumentación , Láseres de Estado Sólido , Modelos Teóricos , Nanotubos de Carbono/química , Oscilometría/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Nanotubos de Carbono/ultraestructura , Dispersión de Radiación
14.
Water Sci Technol ; 58(7): 1441-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18957757

RESUMEN

A fluidized-bed biofilm reactor equipped with a Solid-Polymer-Electrolyte Membrane Electrode (SPEME) cell was developed in order to enhance hydrogenotrophic denitrification of groundwater. Porous cubes made of polyvinylalcohol (PVA) were used as a biofilm carrier and continuous treatments using synthetic groundwater were carried out for 105 days. Electric current was changed step-wise from 0.4 to 4.0 A. Experimental results showed that efficient production and dissolution of hydrogen were achieved by application of electric current as well as high-rate denitrification simultaneously. Denitrification rates of nitrite increased with the increase of electric current. Overall denitrification rates attained to about 90 mg-N/L/h, which was 3 to 9 times as high as those reported in former studies. Supplying electric current of about two times of stoichiometric equivalent to the cell considered necessary for complete denitrification. Water quality in effluent was very stable and electrolytic voltage was low around 3 V. In addition, simple and secure operation was demonstrated over the experiment. From these results, it was concluded that the present fluidized-bed biofilm reactor equipped with a SPEME cell could be very feasible for high-rate hydrogenotrophic denitrification of ground water.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Reactores Biológicos , Electrólitos/química , Polímeros/química , Purificación del Agua/métodos , Electrodos , Hidrógeno/química , Hidrógeno/metabolismo , Membranas Artificiales , Nitritos/química , Nitritos/metabolismo , Nitrógeno/metabolismo , Purificación del Agua/instrumentación , Abastecimiento de Agua/análisis
15.
Water Sci Technol ; 58(3): 705-11, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18725742

RESUMEN

To assess crucial stresses to fish survival in suburban streams, a Life Cycle Risk Assessment (LCRA) was developed and verified by comparing with field survey results. In LCRA, 8 stresses produced by human activities were taken into consideration, referring to the literature. Field survey was conducted over 2 years to identify the present existence and distributions of fishes in 3 streams, which have different pollution levels and morphologies. Field survey results demonstrated that species of fishes and their populations were different in 3 streams and varied with location. Crucial stresses frequently identified by the LCRA were depletion of dissolved oxygen (DO), disappearances of habitats (e.g. deep and shallow), disappearance of spawning area, and existence of obstructions in the streams. Furthermore, most LCRA results regarding existence or non-existence of 15 fishes at 7 different sites were fairly in good agreement with field survey results. From these results, we concluded the present LCRA would be a useful tool in assessing crucial stress as well as in predicting fish species that are able to survive in streams.


Asunto(s)
Monitoreo del Ambiente/métodos , Peces/crecimiento & desarrollo , Estadios del Ciclo de Vida/fisiología , Ríos , Animales , Ecosistema , Medición de Riesgo
16.
Water Sci Technol ; 58(2): 445-50, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18701799

RESUMEN

To achieve stable and simultaneous removal of nitrogen and phosphorus using aerobic granular sludge in a sequencing batch reactor, a real-time control strategy was established, where time derivatives of electric conductivity (EC) and pH were monitored to facilitate the determinations of ends of phosphate release, nitrification and denitrification as well as corresponding optimum time-lengths of anaerobic, oxic, and anoxic phases in treatment cycles. Although biomass concentration in a reactor drastically fluctuated at the startup period because of very short sludge settling time for the formation of aerobic granular sludge, cycle length for proper treatment was automatically adjusted in this control system. Even when characteristics of influent wastewater markedly fluctuated, stable nitrogen and phosphorus removal was successfully attained both before and at pseudo-steady-state. Effluent concentrations of NH4-N, NOx-N and PO4-P were always lower than 0.3 mg/L. On the other hand, when time lengths of the anaerobic/oxic/anoxic phases were fixed, stable nitrogen and phosphorus removal was not accomplished. Therefore, it is clear that the designed control system is very effective to obtain stable treatment performance in simultaneous nitrogen and phosphorus removal by aerobic granular sludge.


Asunto(s)
Nitrógeno/metabolismo , Fósforo/metabolismo , Aguas del Alcantarillado/microbiología , Aerobiosis , Reactores Biológicos , Nitrógeno/química , Fósforo/química , Factores de Tiempo
17.
Bone Joint J ; 100-B(11): 1487-1490, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30418063

RESUMEN

AIMS: The aims of this study were to evaluate the morphology of the ankle in patients with an osteochondral lesion of the talus using 3D CT, and to investigate factors that predispose to this condition. PATIENTS AND METHODS: The study involved 19 patients (19 ankles) who underwent surgery for a medial osteochondral lesion (OLT group) and a control group of 19 healthy patients (19 ankles) without ankle pathology. The mean age was significantly lower in the OLT group than in the control group (27.0 vs 38.9 years; p = 0.02). There were 13 men and six women in each group. 3D CT models of the ankle were made based on Digital Imaging and Communications in Medicine (DICOM) data. The medial malleolar articular and tibial plafond surface, and the medial and lateral surface area of the trochlea of the talus were defined. The tibial axis-medial malleolus (TMM) angle, the medial malleolar surface area and volume (MMA and MMV) and the anterior opening angle of the talus were measured. RESULTS: The mean TMM angle was significantly larger in the OLT group (34.2°, sd 4.4°) than in the control group (29.2°, sd 4.8°; p = 0.002). The mean MMA and MMV were significantly smaller in the OLT group than in the control group (219.8 mm2, sd 42.4) vs (280.5 mm2, sd 38.2), and (2119.9 mm3, sd 562.5) vs (2646.4 mm3, sd 631.4; p < 0.01 and p = 0.01, respectively). The mean anterior opening angle of the talus was significantly larger in the OLT group than in the control group (15.4°, sd 3.9°) vs (10.2°, sd 3.6°; p < 0.001). CONCLUSION: 3D CT measurements showed that, in patients with a medial osteochondral lesion of the talus, the medial malleolus opens distally, the MMA and MMV are small, and the anterior opening angle of the talus is large. This suggests that abnormal morphology of the ankle predisposes to the development of osteochondral lesions of the talus. Cite this article: Bone Joint J 2018;100-B:1487-90.


Asunto(s)
Articulación del Tobillo/diagnóstico por imagen , Osteocondritis Disecante/etiología , Astrágalo/diagnóstico por imagen , Adolescente , Adulto , Articulación del Tobillo/patología , Estudios de Casos y Controles , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Osteocondritis Disecante/diagnóstico por imagen , Osteocondritis Disecante/patología , Osteocondritis Disecante/cirugía , Factores de Riesgo , Astrágalo/patología , Astrágalo/cirugía , Tibia/diagnóstico por imagen , Tibia/patología , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
18.
Kyobu Geka ; 60(2): 117-20, 2007 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-17305077

RESUMEN

Good performance was observed over 10 years after implantation of bipolar epicardial atrial pacing using an active fixation bipolar endocardial lead in 3 pediatric patients with congenital heart block. The bipolar endocardial lead which was supposed to be fixed transvenously was implanted on the atrial surface by first screwing the lead's helix into the myocardium. The catheter was then laid down on the atrial surface, and both electrodes were wrapped by the atrial tissue. The good performance of this pacing lead seemed to depend on stable positioning of the electrode. This lead is superior to the commercially available, and steroid eluting epicardial bipolar pacing lead, on the point of its small size in head and body, and could be applied to dual chamber pacing in smaller children.


Asunto(s)
Estimulación Cardíaca Artificial/métodos , Bloqueo Cardíaco/terapia , Marcapaso Artificial , Niño , Electrodos Implantados , Bloqueo Cardíaco/congénito , Humanos , Lactante , Masculino , Pericardio
19.
Nat Commun ; 8: 14277, 2017 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-28134238

RESUMEN

Inner-shell ionization of an isolated atom typically leads to Auger decay. In an environment, for example, a liquid or a van der Waals bonded system, this process will be modified, and becomes part of a complex cascade of relaxation steps. Understanding these steps is important, as they determine the production of slow electrons and singly charged radicals, the most abundant products in radiation chemistry. In this communication, we present experimental evidence for a so-far unobserved, but potentially very important step in such relaxation cascades: Multiply charged ionic states after Auger decay may partially be neutralized by electron transfer, simultaneously evoking the creation of a low-energy free electron (electron transfer-mediated decay). This process is effective even after Auger decay into the dicationic ground state. In our experiment, we observe the decay of Ne2+ produced after Ne 1s photoionization in Ne-Kr mixed clusters.

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