338 research outputs found
Development and Validation of Responsible Environmental Behavior Scale towards Solid Waste Management (REBS-SWM) in School Setting
This study aimed to develop a valid and reliable instrument to measure undergraduate students' responsible environmental behavior towards solid waste management. Data gathered from 418 undergraduate students provided evidence for validity and reliability of the new instrument consists of 34 behavior items on a six point Likert type scale. Results of the factor analysis with varimax rotation showed that items constituting Responsible Environmental Behavior Scale towards Solid Waste Management (REBS – SWM) were grouped under three subscales: (1) Personality factors; (2) Knowledge on action strategy; and (3) Knowledge on issues. Each item had a factor loading of 0.40 or above with its own scale and the alpha reliability coefficient for all of the three subscales was 0.81. Thus, REBS – SWM is a valid and reliable instrument that can be used in the field of environmental and science education and can be used as basis for management of wastes in school setting
Differential annotation of tRNA genes with anticodon CAT in bacterial genomes
We have developed three strategies to discriminate among the three types of tRNA genes with anticodon CAT (tRNA(Ile), elongator tRNA(Met) and initiator tRNA(fMet)) in bacterial genomes. With these strategies, we have classified the tRNA genes from 234 bacterial and several organellar genomes. These sequences, in an aligned or unaligned format, may be used for the identification and annotation of tRNA (CAT) genes in other genomes. The first strategy is based on the position of the problem sequences in a phenogram (a tree-like network), the second on the minimum average number of differences against the tRNA sequences of the three types and the third on the search for the highest score value against the profiles of the three types of tRNA genes. The species with the maximum number of tRNA(fMet) and tRNA(Met) was Photobacterium profundum, whereas the genome of one Escherichia coli strain presented the maximum number of tRNA(Ile) (CAT) genes. This last tRNA gene and tilS, encoding an RNA-modifying enzyme, are not essential in bacteria. The acquisition of a tRNA(Ile) (TAT) gene by Mycoplasma mobile has led to the loss of both the tRNA(Ile) (CAT) and the tilS genes. The new tRNA has appropriated the function of decoding AUA codons
Flora Matritensis,1 (Pteridophyta)
La flora pteridológica de la provincia de Madrid y comarcas limítrofes consta de 24 géneros, 54 especies, siete subespecies, dos formas y doce híbridos. La obra posee claves para determinar órdenes, géneros, especies, subespecies y formas. Para cada taxon se indica el biotipo, tamaño, ecología, fitosociología, pisos bioclimáticos, corología general y regional, así como la ploidía y número de cromosomas.The pteridological flora from Madrid and surrouding areas comprehends 24 genera, 54 species, 7 subspecies, 2 forms and 12 hybrids. This paper has keys for the determination of all taxa up to the form level. Biotype, size, ecology, phytosociology, vegetation stage, general and regional and regional chorology, plody level and chromosome number is given for each [email protected]
bRing: An observatory dedicated to monitoring the Pictoris b Hill sphere transit
Aims. We describe the design and first light observations from the
Pictoris b Ring ("bRing") project. The primary goal is to detect photometric
variability from the young star Pictoris due to circumplanetary
material surrounding the directly imaged young extrasolar gas giant planet
\bpb. Methods. Over a nine month period centred on September 2017, the Hill
sphere of the planet will cross in front of the star, providing a unique
opportunity to directly probe the circumplanetary environment of a directly
imaged planet through photometric and spectroscopic variations. We have built
and installed the first of two bRing monitoring stations (one in South Africa
and the other in Australia) that will measure the flux of Pictoris,
with a photometric precision of over 5 minutes. Each station uses two
wide field cameras to cover the declination of the star at all elevations.
Detection of photometric fluctuations will trigger spectroscopic observations
with large aperture telescopes in order to determine the gas and dust
composition in a system at the end of the planet-forming era. Results. The
first three months of operation demonstrate that bRing can obtain better than
0.5\% photometry on Pictoris in five minutes and is sensitive to
nightly trends enabling the detection of any transiting material within the
Hill sphere of the exoplanet
Na I and H absorption features in the atmosphere of MASCARA-2b/KELT-20b
We have used the HARPS-North high resolution spectrograph (=115
000) at TNG to observe one transit of the highly irradiated planet
MASCARA-2b/KELT-20b. Using only one transit observation, we are able to clearly
resolve the spectral features of the atomic sodium (Na I) doublet and the
H line in its atmosphere, measuring absorption depths of
0.170.03 and 0.590.08 for a 0.75 passband,
respectively. These absorptions are corroborated with the transmission measured
from their respective transmission light curves, which show a large
Rossiter-McLaughlin effect. In case of H, this absorption corresponds
to an effective radius of =1.200.04. While the S/N of the
final transmission spectrum is not sufficient to adjust different temperature
profiles to the lines, we find that higher temperatures than the equilibrium
are needed to explain the lines contrast. Particularly, we find that the Na I
lines core require a temperature of T=4210180K and that H requires
T=4330520K. MASCARA-2b, like other planets orbiting A-type stars, receives
a large amount of UV energy from its host star. This energy excites the atomic
hydrogen and produces H absorption, leading to the expansion and
abrasion of the atmosphere. The study of other Balmer lines in the transmission
spectrum would allow the determination of the atmospheric temperature profile
and the calculation of the lifetime of the atmosphere. In the case of
MASCARA-2b, residual features are observed in the H and H lines,
but they are not statistically significant. More transit observations are
needed to confirm our findings in Na I and H, and to build up enough
S/N to explore the presence of H and H planetary absorptions.Comment: 14 pages, 12 figure
"It has no meaning to me". How do researchers understand the effectiveness of literature searches? A qualitative analysis and preliminary typology of understandings
This study aimed to address the question: what does “effectiveness” mean to researchers in the context of literature searching for systematic reviews?
We conducted a thematic analysis of responses to an e‐mail survey. Eighty‐nine study authors, whose studies met inclusion in a recent review (2018), were contacted via e‐mail and asked three questions; one directly asking the question: in literature searching, what does effective (or effectiveness in) literature searching mean to you?
Thirty‐eight (46%) responses were received from diverse professional groups, including: literature searchers, systematic reviewers, clinicians and researchers. A shared understanding of what effectiveness means was not identified. Instead, five themes were developed from data: 1) effectiveness is described as a metric; 2) effectiveness is a balance between metrics; 3) effectiveness can be categorised by search purpose; 4) effectiveness is an outcome; and, 5) effectiveness is an experimental concept. We propose that these themes constitute a preliminary typology of understandings.
No single definition of effectiveness was identified. The proposed typology suggests that different researchers have differing understandings of effectiveness. This could lead to uncertainty as to the aim and the purpose of literature searches and confusion about the outcomes. The typology offers a potential route for further exploration
Data calibration for the MASCARA and bRing instruments
Aims: MASCARA and bRing are photometric surveys designed to detect
variability caused by exoplanets in stars with . Such variability
signals are typically small and require an accurate calibration algorithm,
tailored to the survey, in order to be detected. This paper presents the
methods developed to calibrate the raw photometry of the MASCARA and bRing
stations and characterizes the performance of the methods and instruments.
Methods: For the primary calibration a modified version of the coarse
decorrelation algorithm is used, which corrects for the extinction due to the
earth's atmosphere, the camera transmission, and intrapixel variations.
Residual trends are removed from the light curves of individual stars using
empirical secondary calibration methods. In order to optimize these methods, as
well as characterize the performance of the instruments, transit signals were
injected in the data. Results: After optimal calibration an RMS scatter of 10
mmag at is achieved in the light curves. By injecting transit
signals with periods between one and five days in the MASCARA data obtained by
the La Palma station over the course of one year, we demonstrate that MASCARA
La Palma is able to recover 84.0, 60.5 and 20.7% of signals with depths of 2, 1
and 0.5% respectively, with a strong dependency on the observed declination,
recovering 65.4% of all transit signals at versus 35.8% at
. Using the full three years of data obtained by MASCARA La
Palma to date, similar recovery rates are extended to periods up to ten days.
We derive a preliminary occurrence rate for hot Jupiters around A-stars of , knowing that many hot Jupiters are still overlooked. In the era of
TESS, MASCARA and bRing will provide an interesting synergy for finding
long-period ( days) transiting gas-giant planets around the brightest
stars.Comment: 18 pages, 17 figures, accepted for publication in A&
Characterization and prediction of the discharge coefficient of non-cavitating diesel injection nozzles
An experimental and theoretical study about the characterization of the discharge coefficient of diesel
injection nozzles under non-cavitating conditions is presented in this paper. A theoretical development
based on the boundary layer equations has been performed to define the discharge coefficient of a
convergent nozzle. The discharge coefficient has been experimentally obtained for a standard diesel fuel under a wide range of Reynolds numbers by two different techniques: mass flow rate measurements and permeability measurements. Five different nozzles have been used: two multi-hole nozzles that have been tested in the frame of this work, and three other single-hole nozzles, the data of which have been taken from previous studies. The experimental results show good agreement with the theoretical expressions, proving that it is possible to predict the discharge coefficient of a non-cavitating nozzle with the equations shown in this paper.The authors would like to thank different members of the CMT-Motores Termicos team of the Universitat Politecnica de Valencia for their contribution to this work, specially to R. Payri, F.J. Salvador, J. Gimeno and G. Bracho. This work was partly sponsored by "Ministerio de Economia y Competitividad" in the frame of the project "Comprension de la influencia de combustibles no convencionales en el proceso de inyeccion y combustion tipo diesel", reference TRA2012-36932. The equipment used in this work has been partially supported by FEDER project funds "Dotacion de infraestructuras cientifico tecnicas para el Centro Integral de Mejora Energetica y Medioambiental de Sistemas de Transporte (CiMeT), (FEDER-ICTS-2012-06)", in the frame of the operation program of unique scientific and technical infrastructure of the Ministry of Science and Innovation of Spain. This support is gratefully acknowledged by the authors. Finally, the authors would like to thank the Spanish Ministry of Education for financing the PhD. studies of Dario Lopez-Pintor (grant FPU13/02329).Desantes Fernández, JM.; López, JJ.; Carreres Talens, M.; López-Pintor, D. (2016). Characterization and prediction of the discharge coefficient of non-cavitating diesel injection nozzles. Fuel. 184:371-381. https://doi.org/10.1016/j.fuel.2016.07.02637138118
Fixation of bioactive compounds to the cuticle of Artemia
Artemia is extensively used in aquaculture to feed early stages of cultured marine species. A problem associated
with this practice is that Artemia fails to supply some essential nutrients. As a possible solution, we have devised
a procedure to make Artemia a vehicle for exogenous nutrients and other bioactive compounds. It consists of the
construction of chimeric proteins composed of a chitin-binding domain, which binds to the cuticle of Artemia,
and a carrier domain that conveys a functional property. As confirmatory examples, we describe the successful
fixation to Artemia's metanauplii of two hybrid proteins: a β-galactosidase from the thermophilic bacterium
Thermotoga maritima and the jellyfish green fluorescent protein (GFP), both linked to the CBM2 chitin-binding
domain from the hyperthermophilic archaeon Pyrococcus furiosus. Positive results of experiments carried out ex
vivo and in vivo show the validity of this approach. The methodology used could become a general procedure for
the attachment of different kinds of bioactive compounds, such as enzymes, hormones, antibiotics, etc., to the
cuticle of Artemia as well as other arthropods.
Statement of relevance: Our results overcome shortcomings of Artemia as a feedstock.En prensa2,04
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