7,141 research outputs found
Decay time characteristics of La2O2S:Eu and La2O2S:Tb for use within an optical sensor for human skin temperature measurement
We focus on the development of a remote temperature sensing technology, i.e., an optical laser-based sensor, using thermographic phosphors for medical applications, particularly within an electromagnetically hostile magnetic resonance imaging (MRI) environment. A MRI scanner uses a strong magnetic field and radio waves to generate images of the inside of the body. The quality of the image improves with increasing magnetic resonance; however, the drawback of applying a greater magnetic strength is the inducement of heat into the body tissue. Therefore, monitoring the patient’s temperature inside MRI is vital, but until now, a practical solution for temperature measurement did not exist. We show europium doped lanthanum oxysulphide (La2O2S∶Eu) and terbium doped lanthanum oxysulphide (La2O2S∶Tb) are both temperature sensitive to a low temperature range of 10–50 °C when under ultraviolet (UV) excitation. The emission spectra and decay time characteristics of these phosphors were demonstrated. The results indicate that La2O2S∶Eu has a quenching rate of 13:7m°C−1 and 4m°C−1 at 512nm and 538 nm, respectively. In addition, La2O2S∶Tb has a lower quenching rate of 4:19m°C−1 at 548nm due to its faster decay time
A preliminary examination of prehistoric coastal settlement at Nelson Bay, West coast of Tasmania
This paper describes the results and interpretations of a preliminary survey of archaeological sites on the west coast of Tasmania undertaken as part of a PhD project into the prehistory of the area
Effects of soil and canopy characteristics on microwave backscattering of vegetation
A frequency modulated continuous wave C-band (4.8 GHz) scatterometer was mounted on an aerial lift truck and backscatter coefficients of corn were acquired as functions of polarizations, view angles, and row directions. As phytomass and green leaf area index increased, the backscatter also increased. Near anthesis when the canopies were fully developed, the major scattering elements were located in the upper 1 m of the 2.8 m tall canopy and little backscatter was measured below that level. C-band backscatter data could provide information to monitor vegetation at large view zenith angles
Estimating scattered and absorbed radiation in plant canopies by remote sensing
Several research avenues are summarized. The relationships of canopy characteristics to multispectral reflectance factors of vegetation are reviewed. Several alternative approaches for incorporating spectrally derived information into plant models are discussed, using corn as the main example. A method is described and evaluated whereby a leaf area index is estimated from measurements of radiation transmitted through plant canopies, using soybeans as an example. Albedo of a big bluestem grass canopy is estimated from 60 directional reflectance factor measurements. Effects of estimating albedo with substantially smaller subsets of data are evaluated
Profesorado : revista de curriculum y formación del profesorado
Monográfico con el título: “Políticas de evaluación y accountability en la educación"Título, resumen y palabras clave también en españolResumen basado en el de la publicaciónLos servicios públicos pueden desarrollar dos prácticas contrapuestas de rendición de cuentas: el modelo convencional hace hincapié en que ser responsable es "tener en cuenta", que se espera responder a preguntas sobre el rendimiento y que las respuestas son evaluadas por los superiores medidos en función de algún estándar o expectativa, seguido de la alabanza o culpa correspondiente y se aplica la sanción. El modo de rendición de cuentas expresa la jerarquía de autoridad. Un proceso muy diferente alienta el diálogo sobre la rendición de cuentas entre los profesionales y los públicos, que "dan cuenta" ofreciendo un relato que interpreta y explica lo que ha sucedido y por qué ha tenido lugar. Se observan las prácticas contrapuestas en el desarrollo de la gobernanza escolar en Inglaterra y aboga por la importancia del diálogo para mejorar el aprendizaje y la capacidad de respuesta democrática.ES
Unexpectedly high Plasmodium sporozoite rate associated with low human blood index in Anopheles coluzzii from a LLIN-protected village in Burkina Faso.
Despite the effectiveness of mass distribution of long-lasting insecticidal nets (LLINs) in reducing malaria transmission in Africa, in hyperendemic areas such as Burkina Faso the burden of malaria remains high. We here report the results of a 4-month survey on the feeding habits and Plasmodium infection in malaria vectors from a village in Burkina Faso one year following a national LLIN distribution programme. Low values of human blood index (HBI) observed in the major malaria vectors in the area (Anopheles coluzzii: N = 263, 20.1%; An. arabiensis: 5.8%, N = 103) are consistent with the hypothesis that LLINs reduced the availability of human hosts to mosquitoes. A regression meta-analysis of data from a systematic review of published studies reporting HBI and sporozoite rates (SR) for An. gambiae complex revealed that the observed SR values (An. coluzzii: 7.6%, N = 503; An. arabiensis: 5.3%, N = 225) are out of the ranges expected based on the low HBI observed. We hypothesize that a small fraction of inhabitants unprotected by bednets acts as a "core group" repeatedly exposed to mosquito bites, representing the major Plasmodium reservoir for the vectors, able to maintain a high risk of transmission even in a village protected by LLINs
Understanding fatherhood in the digital age
In this blog, Gillian Ranson looks into the rise of the father blogger. Recognising their growing impact, she reflects on the role of father bloggers with advertising as they become a potential source of revenue, as well as their position as ‘parent experts’ who are professionalised as fathers. Gillian is Professor Emerita of Sociology at the University of Calgary, Canada. She is currently working on a book project examining parenting culture in Canada today
Efficacy of Olyset Duo, a bednet containing pyriproxyfen and permethrin, versus a permethrin-only net against clinical malaria in an area with highly pyrethroid-resistant vectors in rural Burkina Faso: a cluster-randomised controlled trial.
BACKGROUND
Substantial reductions in malaria incidence in sub-Saharan Africa have been achieved with massive deployment of long-lasting insecticidal nets (LLINs), but pyrethroid resistance threatens control. Burkina Faso is an area with intense malaria transmission and highly pyrethroid-resistant vectors. We assessed the effectiveness of bednets containing permethrin, a pyrethroid, and pyriproxyfen, an insect growth regulator, versus permethrin-only (standard) LLINs against clinical malaria in children younger than 5 years in Banfora, Burkina Faso.
METHODS
In this two-group, step-wedge, cluster-randomised, controlled, superiority trial, standard LLINs were incrementally replaced with LLINs treated with permethrin plus pyriproxyfen (PPF) in 40 rural clusters in Burkina Faso. In each cluster, 50 children (aged 6 months to 5 years) were followed up by passive case detection for clinical malaria. Cross-sectional surveys were done at the start and the end of the transmission seasons in 2014 and 2015. We did monthly collections from indoor light traps to estimate vector densities. Primary endpoints were the incidence of clinical malaria, measured by passive case detection, and the entomological inoculation rate. Analyses were adjusted for clustering and for month and health centre. This trial is registered as ISRCTN21853394.
FINDINGS
1980 children were enrolled in the cohort in 2014 and 2157 in 2015. At the end of the study, more than 99% of children slept under a bednet. The incidence of clinical malaria was 2·0 episodes per child-year in the standard LLIN group and 1·5 episodes per child-year in the PPF-treated LLIN group (incidence rate ratio 0·88 [95% CI 0·77-0·99; p=0·04]). The entomological inoculation rate was 85 (95% CI 63-108) infective bites per transmission season in the standard LLIN group versus 42 (32-52) infective bites per transmission season in the PPF-treated LLIN group (rate ratio 0·49, 95% CI 0·32-0·66; p<0·0001).
INTERPRETATION
PPF-treated LLINs provide greater protection against clinical malaria than do standard LLINs and could be used as an alternative to standard LLINs in areas with intense transmission of Plasmodium falciparum malaria and highly pyrethroid-resistant vectors.
FUNDING
EU Seventh Framework Programme
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