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1.
Sensors (Basel) ; 20(15)2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32731395

RESUMEN

In this study, we demonstrate a strain sensor fabricated as a hybrid structure of a conductive intermittent pattern with embedded single droplets of a functional resistive ink. The main feature of our proposed sensor design is that although the intermittent pattern comprises the majority of the entire sensor area, the strain sensitivity depends almost selectively on the resistive droplets. This opens up the possibility for fast and inexpensive evaluation of sensors manufactured from various functional materials. As the use of resistive ink was limited to single droplets deposition, the required ink amount needed to build a sensor can be considerably reduced. This makes the sensors cost-effective and simple for fabrication. In this study, our proposed sensor design was evaluated when a carbon-based ink was used as the resistive material incorporated into an intermittent structure made of silver. The developed strain sensors were tested during bending deformations demonstrating good strain sensitivity (gauge factor: 7.71) and no hysteresis within the investigated strain range.

2.
Appl Microbiol Biotechnol ; 100(19): 8573-82, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27311565

RESUMEN

For the past few decades, human activities have intensively increased the reactive nitrogen enrichment in China's coastal wetlands. Although denitrification is a critical pathway of nitrogen removal, the understanding of denitrifier community dynamics driving denitrification remains limited in the coastal wetlands. In this study, the diversity, abundance, and community composition of nirS-encoding denitrifiers were analyzed to reveal their variations in China's coastal wetlands. Diverse nirS sequences were obtained and more than 98 % of them shared considerable phylogenetic similarity with sequences obtained from aquatic systems (marine/estuarine/coastal sediments and hypoxia sea water). Clone library analysis revealed that the distribution and composition of nirS-harboring denitrifiers had a significant latitudinal differentiation, but without a seasonal shift. Canonical correspondence analysis showed that the community structure of nirS-encoding denitrifiers was significantly related to temperature and ammonium concentration. The nirS gene abundance ranged from 4.3 × 10(5) to 3.7 × 10(7) copies g(-1) dry sediment, with a significant spatial heterogeneity. Among all detected environmental factors, temperature was a key factor affecting not only the nirS gene abundance but also the community structure of nirS-type denitrifiers. Overall, this study significantly enhances our understanding of the structure and dynamics of denitrifying communities in the coastal wetlands of China.


Asunto(s)
Biota , Desnitrificación , Microbiología Ambiental , Nitrito Reductasas/análisis , Filogeografía , Humedales , Compuestos de Amonio/análisis , China , Metagenómica , Nitrito Reductasas/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Temperatura , Agua/química
3.
Anesth Analg ; 111(4): 1004-10, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20705788

RESUMEN

BACKGROUND: Dexmedetomidine, a specific α(2) agonist, has an analgesic-sparing effect and reduces emergence agitation. We compared an intraoperative dexmedetomidine infusion with bolus fentanyl to reduce perioperative opioid use and decrease emergence agitation in children with obstructive sleep apnea syndrome undergoing adenotonsillectomy (T&A). METHODS: One hundred twenty-two patients with obstructive sleep apnea syndrome undergoing T&A, ages 2 to 10 years, completed this prospective, randomized, U.S. Food and Drug Administration-approved study. After mask induction with sevoflurane, group D received IV dexmedetomidine 2 µg · kg(-1) over 10 minutes, followed by 0.7 µg · kg(-1) · h(-1), and group F received IV fentanyl bolus 1 µg · kg(-1). Anesthesia was maintained with sevoflurane, oxygen, and nitrous oxide. Fentanyl 0.5 to 1 µg · kg(-1) was given to subjects in both groups for an increase in heart rate or systolic blood pressure 30% above preincision values that continued for 5 minutes. Observers in the postanesthesia care unit (PACU) were blinded to treatment groups. Pain was evaluated using the objective pain score in the PACU on arrival, at 5 minutes, at 15 minutes, then every 15 minutes for 120 minutes. Emergence agitation was evaluated at the same intervals by 2 scales: the Pediatric Anesthesia Emergence Delirium scale and a 5-point scale described by Cole. Morphine (0.05 to 0.1 mg · kg(-1)) was given for pain (score >4) or severe agitation (score 4 or 5) lasting more than 5 minutes. RESULTS: In group D, 9.8% patients needed intraoperative rescue fentanyl in comparison with 36% in group F (P = 0.001). Mean systolic blood pressure and heart rate were significantly lower in group D (P < 0.05). Minimum alveolar concentration values were significantly different between the 2 groups (P = 0.015). The median objective pain score was 3 for group D and 5 for group F (P = 0.001). In group D, 10 (16.3%) patients required rescue morphine, in comparison with 29 (47.5%) in group F (P = 0.002). The frequency of severe emergence agitation on arrival in the PACU was 18% in group D and 45.9% in group F (P = 0.004); at 5 minutes and at 15 minutes, it was lower in group D (P = 0.028). The duration of agitation on the Cole scale was statistically lower in group D (P = 0.004). In group D, 18% of patients and 40.9% in group F had an episode of Spo(2) below 95% (P = 0.01). CONCLUSIONS: An intraoperative infusion of dexmedetomidine combined with inhalation anesthetics provided satisfactory intraoperative conditions for T&A without adverse hemodynamic effects. Postoperative opioid requirements were significantly reduced, and the incidence and duration of severe emergence agitation was lower with fewer patients having desaturation episodes.


Asunto(s)
Adenoidectomía , Periodo de Recuperación de la Anestesia , Dexmedetomidina/administración & dosificación , Agitación Psicomotora/prevención & control , Apnea Obstructiva del Sueño/cirugía , Tonsilectomía , Adenoidectomía/efectos adversos , Analgesia/métodos , Analgésicos no Narcóticos/administración & dosificación , Niño , Preescolar , Femenino , Fentanilo/administración & dosificación , Humanos , Infusiones Intravenosas , Masculino , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Agitación Psicomotora/etiología , Apnea Obstructiva del Sueño/tratamiento farmacológico , Tonsilectomía/efectos adversos
4.
Vision Res ; 42(8): 1063-70, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11934456

RESUMEN

Wavefront aberrations were measured using a psychophysical ray-tracing technique in both eyes of 316 emmetropic and moderately myopic school children and young adults. Myopic subjects were found to have greater mean root mean square (RMS) value of wavefront aberrations than emmetropic subjects. Emmetropic adults had the smallest mean RMS, which remained smaller than the values for myopic adults and children and for emmetropic children both when second order Zernike aberrations (astigmatism) and third order Zernike aberrations were removed. Twenty percent of myopic adults had RMS values greater than values for all of the emmetropic adults, with significantly greater values for Zernike aberrations from second to seventh orders. High amounts of wavefront aberrations, which degrade the retinal image, may play a role in the development of myopia.


Asunto(s)
Miopía/fisiopatología , Refracción Ocular/fisiología , Adolescente , Adulto , Envejecimiento/fisiología , Astigmatismo/fisiopatología , Niño , Humanos , Psicofísica , Factores de Riesgo
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