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1.
Indoor Air ; 25(5): 499-511, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25244340

RESUMEN

A nationwide cross-sectional study of 3335 employees was conducted in 320 offices in Japan to estimate the prevalence of building-related symptoms (BRSs) and determine the risk factors related to work environment, Indoor Air Quality, and occupational stress. Data were collected through self-administered questionnaires. The prevalences of general symptoms, eye irritation, and upper respiratory symptoms were 14.4%, 12.1%, and 8.9%, respectively. Multiple logistic regression analyses revealed that eye irritation was significantly associated with carpeting [odds ratio (OR), 1.73; 95% confidence interval (CI), 1.24-2.41], coldness perception (OR, 1.28; 95% CI, 1.13-1.45), and air dryness perception (OR, 1.61; 95% CI, 1.42-1.82). General symptoms were significantly associated with unpleasant odors (OR, 1.37; 95% CI, 1.13-1.65), amount of work (OR, 1.24; 95% CI, 1.06-1.45), and interpersonal conflicts (OR, 1.44; 95% CI, 1.23-1.69). Upper respiratory symptoms were significantly associated with crowded workspaces (OR, 1.36; 95% CI, 1.13-1.63), air dryness perception (OR, 2.07; 95% CI, 1.79-2.38), and reported dustiness on the floor (OR, 1.39; 95% CI, 1.16-1.67). Although psychosocial support is important to reduce and control BRSs, maintaining appropriate air-conditioning and a clean and uncrowded workspace is of equal importance.


Asunto(s)
Contaminación del Aire Interior , Exposición Profesional/efectos adversos , Síndrome del Edificio Enfermo/epidemiología , Adulto , Estudios Transversales , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Síndrome del Edificio Enfermo/etiología , Estrés Psicológico/complicaciones , Adulto Joven
2.
Indoor Air ; 24(4): 425-37, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24354902

RESUMEN

UNLABELLED: Thermal conditions and indoor concentrations of aldehydes, volatile organic compounds (VOCs), and NO2 were investigated in 19 occupied temporary houses in 15 temporary housing estates constructed in Minamisoma City, Fukushima, Japan. The data were collected in winter, spring, and summer in January to July 2012. Thermal conditions in temporary log houses in the summer were more comfortable than those in pre-fabricated houses. In the winter, the indoor temperature was uncomfortably low in all of the houses, particularly the temporary log houses. Indoor air concentrations for most aldehydes and VOCs were much lower than the indoor guidelines, except for those of p-dichlorobenzene, acetaldehyde, and total VOCs. The indoor p-dichlorobenzene concentrations exceeded the guideline (240 µg/m(3)) in 18% of the temporary houses, and the 10(-3) cancer risk level (91 µg/m(3)) was exceeded in winter in 21% due to use of moth repellents by the occupants. Indoor acetaldehyde concentrations exceeded the guideline (48 µg/m(3) ) in about half of the temporary houses, likely originating from the wooden building materials. Indoor NO2 concentrations in the temporary houses were significantly higher in houses where combustion heating appliances were used (0.17 ± 0.11 ppm) than in those where they were not used (0.0094 ± 0.0065 ppm). PRACTICAL IMPLICATIONS: In the winter, log-house-type temporary houses are comfortable in terms of humidity, dew condensation, and fungi based on the results of questionnaires and measurements, whereas pre-fabricated temporary houses are more comfortable in terms of temperature. In the summer, log-house-type temporary houses are comfortable in terms of temperature and humidity. More comfortable temporary housing in terms of temperature and humidity year-round is needed. Indoor air concentrations of p-dichlorobenzene and NO2 were quite high in some temporary houses due to occupants' activities, such as use of moth repellents and combustion heating appliances. The government should provide recommendations for safe use of temporary houses by occupants.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Dióxido de Nitrógeno/análisis , Compuestos Orgánicos Volátiles/análisis , Distribución de Chi-Cuadrado , Terremotos , Calefacción , Vivienda , Humanos , Humedad , Japón , Estaciones del Año , Encuestas y Cuestionarios , Temperatura
3.
J Mass Spectrom ; 34(10): 1063-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10510429

RESUMEN

The mass spectral properties of glucuronides of the 9- and 10-hydroxylated metabolites of RT-3003 (Vintoperol; (-)-1beta-ethyl-1alpha-hydroxymethyl-1,2,3,4,6,7, 12balpha-octahydroindolo[2,3-a]quinolizine), which were fractionated by high-performance liquid chromatography with fluorescence detection, were investigated using the positive ion electrospray ionization mode. These glucuronides showed predominantly the protonated molecular ion ([M + H](+) ion), and the [M + H](+) ion provided a characteristic product ion spectrum in which abundant ions were obtained at m/z 301, 160 and 142. The first ion, corresponding to the [aglycone + H](+) ion, was produced by neutral loss of the glucuronic acid moiety from the [M + H](+) ion. The product ion spectrum of the [M + H](+) ion of hydroxy-RT-3003 revealed a number of ions common to the glucuronide spectra, suggesting that other two ions observed most likely represent fragmentation of hydroxy-RT-3003. In turn, these glucuronides were positional isomers with respect to the binding site of glucuronic acid. The structures of the isomer pairs were discriminated by the presence of the ion of m/z 318 or 336 in the product ion spectrum. These ions were produced by fission of the C-ring, the same as for the formation of the ions of m/z 160 and 142, as were observed in the product ion spectrum from the [M + H](+) ion of hydroxy-RT-3003. For the formation of these ions, an unusual fragmentation process was proposed, and these ion structures were supported by evidence from the accurate mass measurement data. Additionally, in the sulfates of hydroxylated metabolites, a similar product ion corresponding to the ion of m/z 336 found in the phenolic glucuronides was observed, and was applied for identification of the sulfate metabolites.


Asunto(s)
Glucurónidos/análisis , Indoles/análisis , Indoles/farmacocinética , Quinolizinas/análisis , Quinolizinas/farmacocinética , Vasodilatadores/análisis , Vasodilatadores/farmacocinética , Animales , Biotransformación , Cromatografía Líquida de Alta Presión , Perros , Hidroxilación , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Masculino , Espectrometría de Masas , Ratas , Espectrometría de Fluorescencia
4.
Opt Lett ; 21(8): 573-5, 1996 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19876087

RESUMEN

The bandwidth of a single-pump fiber optical parametric amplifier is governed by the even orders of fiber dispersion at the pump wavelength. The amplifier can exhibit gain over a wide wavelength range when operated near the fiber's zero-dispersion wavelength. It can also be used for broadband wavelength conversion,with gain. We have experimentally obtained gain of 10-18 dB as the signal wavelength was tuned over a 35-nm bandwidth near 1560 nm.

5.
Rapid Commun Mass Spectrom ; Spec No: S116-22, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8829476

RESUMEN

11-Dehydro-2,3-dinorthromboxane B3 (an enzymatic metabolite of TXB3) was identified. Urine from a healthy male adult who had received daily administration of 1.8 g (0.6 g three times) of eicosapentaenoic acid (EPA) ethyl ester was collected. A urine sample was extracted with an affinity column of anti-11-dehydro-TXB2 monoclonal antibody. Conversion of 11-dehydro-2,3-dinor-TXB3 in the urine extract into the methyl ester (ME)-11-n-propylamide (PA)-9, 12, 15-dimethylisopropylsilyl (DMIPS) ether derivative was followed by gas chromatography with selected-ion monitoring (GC/SIM) (resolution: 8000) and GC/mass spectrometry (MS). High-resolution SIM result revealed that a major component corresponded to the [M - C3H7]+ (m/z 668.4198) ion, which may be specific for the structural integrity by analogy with the corresponding 11-dehydro-TXB3 derivative. Conventional GC/MS analysis confirmed that the peak of the interest was the title compound. The mass spectrum of the 11-dehydro-2,3-dinor-TXB3 ME-PA-DMIPS ether derivative was dominated by the ions of [M - CH3]+ (m/z 696) and [M - C3H7]+ (m/z 668, base peak) and ions containing a protected 11-carboxylic acid moiety together with the unidentified additional ions which were considered to derive from urinary endogenous substances. However, the quality was sufficient for use of mass spectral identification of 11-dehydro-2,3-dinor-TXB3, the beta-oxidation product of 11-dehydro-TXB3. Characteristic fragment ions of [M - C5H9-(dimethylisopropylsilanol)n]+ (m/z 524 and 406) yielding information about the position of the incorporated double bond were prominent, the same as the corresponding ions found in the mass spectrum of the 11-dehydro-TXB3 derivative. Consequently, the fragmentation products were closely related to those of the 11-dehydro-TXB3 derivative, except for an obvious shift produced by the lack of C-2/C-3 hydrocarbon units. The results demonstrate the endogenous formation of TXA3 in humans after administration of EPA ethyl ester and excretion of 11-dehydro-2,3-dinor-TXB3 into urine as one of the enzymatic metabolites of TXB3, together with the previously reported 11-dehydro-TXB3.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Tromboxano B2/análogos & derivados , Adulto , Anticuerpos Monoclonales/química , Cromatografía de Afinidad , Humanos , Indicadores y Reactivos , Masculino , Espectrometría de Masas , Tromboxano B2/aislamiento & purificación , Tromboxano B2/orina
6.
Opt Lett ; 20(8): 863-5, 1995 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19859355

RESUMEN

We show that in principle it is possible to cancel third-order nonlinear effects in optical fiber links. The necessary conditions exist in two-segment links, with dispersion compensation, phase conjugation, and amplification between the two, as well as opposite chromatic dispersion coefficients in the segments. The cancellation is independent of loss, modulation format, and modulation frequency.

7.
Anal Chem ; 71(18): 4100-6, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10500493

RESUMEN

Oligosaccharides released from several glycoproteins were derivatized with either 4-aminobenzoic acid 2-(diethylamino)ethyl ester (ABDEAE) (Yoshino, K.; et al. Anal. Chem. 1995, 67, 4028-4031) or 2-aminopyridine. The resulting derivatives were analyzed on a nanoflow electrospray ionization (ESI) quadrupole-inlet time-of-flight mass spectrometer using the low-energy collision-induced dissociation technique. In the MS/MS spectra, the oxonium (b or internal series) and y series ions, which are derived from the multiply charged precursor ions, were predominant and were used for the structural readout. Some oxonium ions that were observed in the low-mass region, but that were not found in the PSD analyses (Mo, W.; et al. Anal. Chem. 1998, 70, 4520-4526), rendered a more detailed structural insight. The oxonium ions at m/z 512.2, which are derived from the fucosylated oligosaccharides of immunoglobulin Y and thyroglobulin, were observed, suggesting that fucosylation had occurred proximal to the outer nonreducing terminus. In addition, the data herein show that structural elucidation can be routinely achieved at a low sample concentration. For the case of ABDEAE derivatives, this can be achieved at the 50 fmol/microL level and with the actual sample consumption at the attomole level using nanoflow ESI MS/MS.


Asunto(s)
Oligosacáridos/análisis , Aminopiridinas/química , Secuencia de Carbohidratos , Inmunoglobulinas/análisis , Inmunoglobulinas/química , Espectrometría de Masas/métodos , Datos de Secuencia Molecular , Oligosacáridos/química , Procaína/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tiroglobulina/análisis , Tiroglobulina/química , Transferrina/análisis , Transferrina/química
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