678 research outputs found
Responsible Consumption Behaviour: A Framework for Acquisition, Use & Disposal of Computers
Green IT has been identified as a contributing factor in maintaining a green environment. However, past studies have focused mainly on Green IT practised by IT vendors or organizations rather than by individual consumers. Malaysia is a developing nation with high computer penetration. Almost every citizen is owns several computers, from desktops, tablet PCs, laptops, notebooks to smartphones. This contributes to unsustainable computer production, consumption, and disposal patterns. Greenhouse gas (GHG) emission resulting from computer life cycles can be reduced if individuals acquire, use, and dispose computers in a responsible manner. Hence, this study investigates the antecedents of individuals’ responsible consumption behaviour. A research framework was developed through integrating several theories, i.e. Theory of Planned Behaviour, Value-Belief-Norm, and Theory of Interpersonal Behaviour. This study contributes to existing knowledge in the fields of information systems, consumer research, and sustainability, through the development of a theoretical framework that identifies the key factors that influence responsible consumption behaviour. The findings will enable policy makers to design programmes that could influence behavioural change and stimulate responsible consumption behavior, in order to prevent further degradation of the natural environment
A national study of choanal atresia in tertiary care centers in Canada – part II: clinical management
Background: To evaluate the clinical management of choanal atresia (CA) in tertiary centers across Canada. Methods: Multi-centre case series involving six tertiary care pediatric hospitals across Canada. Retrospective chart review of patients born between 1980 and 2010 diagnosed with choanal atresia to a participating center. Results: The health charts of 215 patients (59.6% female) with choanal atresia (CA) were reviewed. Mean age of initial surgical repair was 0.8 months for bilateral CA, and 48.6 months for unilateral CA. Approaches of surgical repair consisted of endoscopic transnasal (31.7%), non-endoscopic transnasal (42.6%), and transpalatal (25.2%). Stents were used on 70.7% of patients. Forty-nine percent of patients were brought back to the OR for a planned second look; stent removal being the most common reason (86.4%). Surgical success rate of initial surgeries was 54.1%. Surgical technique was not associated with rate of restenosis [χ2 (2) = 1.6, p =.46]. Conclusions: The present study is the first national multi-institutional study exploring the surgical outcomes of CA over a 30-year period. The surgical repair of CA presents a challenge to otolaryngologists, as the rate of surgical failure is high. The optimal surgical approach, age at surgical repair, use of stents, surgical adjuncts, and need for planned second look warrant further investigation. Graphical abstract: [Figure not available: see fulltext.
A national study of choanal atresia in tertiary care centers in Canada – part I: clinical presentation
Background: To evaluate the clinical presentation of choanal atresia (CA) in tertiary centers across Canada. Methods: Multi-centre case series involving six tertiary care pediatric hospitals across Canada. Retrospective chart review of patients born between 1980 and 2010 diagnosed with CA at a participating center. Results: The health charts of 215 patients (59.6% female) with CA were reviewed and included in this study. The mean age of patients at time of CA presentation was 0.4 months (range 0.1 to 7.2 months) for bilateral CA and 37.8 months (range 0.1 to 164.1 months) for unilateral cases. The most common presenting symptoms for bilateral CA in decreasing order were respiratory distress (96.4%), feeding difficulties (68.2%), and rhinorrhea (65.5%), and for unilateral cases in decreasing order were rhinorrhea (92.0%), feeding difficulties (24.7%), and respiratory distress (18.0%). For the majority of patients (73.2%), the obstruction comprised mixed bony and membranous tissue, with only 10.5% presenting with a purely membranous obstruction. Familial history of CA was confirmed in only 3.3% of cases. One half of patients with CA presented with one or more associated anomalies and 30.6% had a syndrome. Conclusions: The present investigation is the first national multi-institutional study evaluating the clinical presentation of CA over three decades. The present cohort of CA patients presented with a breadth of co-morbidities with highly variable presentations, with bilateral cases being more severely affected than unilateral cases. Further investigation into hereditary linkages to CA development is warranted. Graphical abstract: [Figure not available: see fulltext.
Genetic lesions within the 3a gene of SARS-CoV
A series of frameshift mutations within the 3a gene has been observed in culture-derived severe
acute respiratory syndrome coronavirus (SARS-CoV). We report here that viral RNA from clinical
samples obtained from SARS-CoV infected patients also contains a heterogeneous population of
wild-type and mutant 3a transcripts.Web of Scienc
Higgs-Boson Production Associated with a Single Bottom Quark in Supersymmetric QCD
Due to the enhancement of the couplings between Higgs boson and bottom quarks
in the minimal sypersymmetric standard model (MSSM), the cross section of the
process pp(p\bar{p}) \to h^0b(h^0\bar{b})+X at hadron colliders can be
considerably enhanced. We investigated the production of Higgs boson associated
with a single high-p_T bottom quark via subprocess bg(\bar{b}g) \to
h^0b(h^0\bar{b}) at hadron colliders including the next-to-leading order (NLO)
QCD corrections in MSSM. We find that the NLO QCD correction in the MSSM
reaches 50%-70% at the LHC and 60%-85% at the Fermilab Tevatron in our chosen
parameter space.Comment: accepted by Phys. Rev.
Cellular Characterization of SARS Coronavirus Nucleocapsid
The Severe and Acute Respiratory Syndrome coronavirus (SARS CoV) is a newly-emerged virus that caused an outbreak of atypical pneumonia in the winter of 2002-2003. Polyclonal antibodies raised against the nucleocapsid (N) of the SARS CoV showed the localization of N to the cytoplasm and the nucleolus in virus-infected and N-expressing Vero E6 cells. Like other coronavirus N proteins, the SARS N is probably a phosphoprotein. N protein expressed in mammalian cells is apparently able to “spread” to neighboring cells. For N to spread to neighboring cells, it must be exported out of the expressing cells. This is shown by the immunoprecipitation of N from the culture medium of a stable cell line expressing myc-N. Deletion studies showed that the 27 kD C-terminal domain of N (C1/2) is the minimal region of N that can spread to other cells. The nucleolar localization and spreading of N are artefacts of fixation, reminiscent of other protein-transduction domain (PTD)-containing proteinsWeb of Scienc
A Novel Severe Acute Respiratory Syndrome Coronavirus Protein, U274, is transported to the Cell Surface and undergoes Endocytosis
The severe acute respiratory syndrome coronavirus (SARS-CoV) genome contains open reading frames
(ORFs) that encode for several genes that are homologous to proteins found in all known coronaviruses. These
are the replicase gene 1a/1b and the four structural proteins, nucleocapsid (N), spike (S), membrane (M), and
envelope (E), and these proteins are expected to be essential for the replication of the virus. In addition, this
genome also contains nine other potential ORFs varying in length from 39 to 274 amino acids. The largest
among these is the first ORF of the second longest subgenomic RNA, and this protein (termed U274 in the
present study) consists of 274 amino acids and contains three putative transmembrane domains. Using
antibody specific for the C terminus of U274, we show U274 to be expressed in SARS-CoV-infected Vero E6 cells
and, in addition to the full-length protein, two other processed forms were also detected. By indirect immunofluorescence,
U274 was localized to the perinuclear region, as well as to the plasma membrane, in both
transfected and infected cells. Using an N terminus myc-tagged U274, the topology of U274 and its expression
on the cell surface were confirmed. Deletion of a cytoplasmic domain of U274, which contains Yxx and
diacidic motifs, abolished its transport to the cell surface. In addition, U274 expressed on the cell surface can
internalize antibodies from the culture medium into the cells. Coimmunoprecipitation experiments also
showed that U274 could interact specifically with the M, E, and S structural proteins, as well as with U122,
another protein that is unique to SARS-CoV.Web of Scienc
Pseudoscalar Higgs boson production associated with a single bottom quark at hadron colliders
We compute the complete next-to-leading order (NLO) SUSY-QCD corrections for
the associated production of a pseudoscalar Higgs boson with a bottom quark via
bottom-gluon fusion at the CERN Large Hadron Collider (LHC) and the Fermilab
Tevatron. We find that the NLO QCD correction in the MSSM reaches
at the LHC and at the Tevatron in our chosen parameter space
High Q micro-ring resonators fabricated from polycrystalline aluminum nitride films for near infrared and visible photonics
We demonstrate wideband integrated photonic circuits in sputter-deposited
aluminum nitride (AlN) thin films. At both near-infrared and visible
wavelengths, we achieve low propagation loss in integrated waveguides and
realize high-quality optical resonators. In the telecoms C-band (1520-1580 nm),
we obtain the highest optical Q factor of 440,000. Critical coupled devices
show extinction ratio above 30 dB. For visible wavelengths (around 770 nm),
intrinsic quality factors in excess of 30,000 is demonstrated. Our work
illustrates the potential of AlN as a low loss material for wideband optical
applications
Spinodal Decomposition in a Binary Polymer Mixture: Dynamic Self Consistent Field Theory and Monte Carlo Simulations
We investigate how the dynamics of a single chain influences the kinetics of
early stage phase separation in a symmetric binary polymer mixture. We consider
quenches from the disordered phase into the region of spinodal instability. On
a mean field level we approach this problem with two methods: a dynamical
extension of the self consistent field theory for Gaussian chains, with the
density variables evolving in time, and the method of the external potential
dynamics where the effective external fields are propagated in time. Different
wave vector dependencies of the kinetic coefficient are taken into account.
These early stages of spinodal decomposition are also studied through Monte
Carlo simulations employing the bond fluctuation model that maps the chains --
in our case with 64 effective segments -- on a coarse grained lattice. The
results obtained through self consistent field calculations and Monte Carlo
simulations can be compared because the time, length, and temperature scales
are mapped onto each other through the diffusion constant, the chain extension,
and the energy of mixing. The quantitative comparison of the relaxation rate of
the global structure factor shows that a kinetic coefficient according to the
Rouse model gives a much better agreement than a local, i.e. wave vector
independent, kinetic factor. Including fluctuations in the self consistent
field calculations leads to a shorter time span of spinodal behaviour and a
reduction of the relaxation rate for smaller wave vectors and prevents the
relaxation rate from becoming negative for larger values of the wave vector.
This is also in agreement with the simulation results.Comment: Phys.Rev.E in prin
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