5,166 research outputs found
Dip-coated La2Ti2O7 as a buffer layer for growth of Bi3.25La0.75Ti3O12 films with enhanced (0 1 1) orientation
Thin-films of La2Ti2O7 were obtained by dip-coating process using a precursor salt in nitric acid solution. The effects of solution concentration, withdrawal speed, post-annealing duration and temperature were investigated both on grain size and orientation of the La2Ti2O7 thin layers. In addition, a target with the required stoichiometry for PVD deposition of La-substituted Bi4Ti3O12 (BLT) was successfully sintered by spark plasma sintering (SPS) at 750 ◦C. Finally (0 1 1)-oriented BLT ferroelectric films have been grown by RF sputtering on (1 1 0)-oriented La2Ti2O7 polycrystalline thin-film. A preferential orientation of BLT thin films has been obtained after annealing at a temperature lower than 650 ◦C
Validation Guidelines for IS Positivist Research
The issue of whether IS positivist researchers were sufficiently validating their instruments was initially raised fifteen years ago and rigor in IS research is still one of the most critical scientific issues facing the field. Without solid validation of the instruments that are used to gather data on which findings and interpretations are based, the very scientific basis of the profession is threatened. This study builds on four prior retrospectives of IS research that conclude that IS positivist researchers continue to face major barriers in instrument, statistical, and other forms of validation. It goes beyond these studies by offering analyses of the state-of-the-art of research validities and deriving specific heuristics for research practice in the validities. Some of these heuristics will, no doubt, be controversial. But we believe that it is time for the IS academic profession to bring such issues into the open for community debate. This article is a first step in that direction. Based on our interpretation of the importance of a long list of validities, this paper suggests heuristics for reinvigorating the quest for validation in IS research via content/construct validity, reliability, manipulation validity, and statistical conclusion validity. New guidelines for validation and new research directions are offered
The highly conserved serine threonine kinase StkP of Streptococcus pneumoniae contributes to penicillin susceptibility independently from genes encoding penicillin-binding proteins
<p>Abstract</p> <p>Background</p> <p>The serine/threonine kinase StkP of <it>Streptococcus pneumoniae </it>is a major virulence factor in the mouse model of infection. StkP is a modular protein with a N-terminal kinase domain a C-terminal PASTA domain carrying the signature of penicillin-binding protein (PBP) and prokaryotic serine threonine kinase. In laboratory cultures, one target of StkP is the phosphoglucosamine mutase GlmM involved in the first steps of peptidoglycan biosynthesis. In order to further elucidate the importance of StkP in <it>S. pneumoniae</it>, its role in resistance to β-lactams has been assessed by mutational analysis in laboratory cultures and its genetic conservation has been investigated in isolates from infected sites (virulent), asymptomatic carriers, susceptible and non-susceptible to β-lactams.</p> <p>Results</p> <p>Deletion replacement mutation in <it>stkP </it>conferred hypersensitivity to penicillin G and was epistatic on mutations in PBP2X, PBP2B and PBP1A from the resistant 9V clinical isolate URA1258. Genetic analysis of 55 clinical isolates identified 11 StkP alleles differing from the reference R6 allele. None relevant mutation in the kinase or the PASTA domains were found to account for susceptibility of the isolates. Rather the minimal inhibitory concentration (MIC) values of the strains appeared to be determined by their PBP alleles.</p> <p>Conclusion</p> <p>The results of genetic dissection analysis in lab strain Cp1015 reveal that StkP is involved in the bacterial response to penicillin and is epistatic on mutations PBP 2B, 2X and 1A. However analysis of the clinical isolates did not allow us to find the StkP alleles putatively involved in determining the virulence or the resistance level of a given strain, suggesting a strong conservation of StkP in clinical isolates.</p
Exploration of finite dimensional Kac algebras and lattices of intermediate subfactors of irreducible inclusions
We study the four infinite families KA(n), KB(n), KD(n), KQ(n) of finite
dimensional Hopf (in fact Kac) algebras constructed respectively by A. Masuoka
and L. Vainerman: isomorphisms, automorphism groups, self-duality, lattices of
coideal subalgebras. We reduce the study to KD(n) by proving that the others
are isomorphic to KD(n), its dual, or an index 2 subalgebra of KD(2n). We
derive many examples of lattices of intermediate subfactors of the inclusions
of depth 2 associated to those Kac algebras, as well as the corresponding
principal graphs, which is the original motivation.
Along the way, we extend some general results on the Galois correspondence
for depth 2 inclusions, and develop some tools and algorithms for the study of
twisted group algebras and their lattices of coideal subalgebras. This research
was driven by heavy computer exploration, whose tools and methodology we
further describe.Comment: v1: 84 pages, 13 figures, submitted. v2: 94 pages, 15 figures, added
connections with Masuoka's families KA and KB, description of K3 in KD(n),
lattices for KD(8) and KD(15). v3: 93 pages, 15 figures, proven lattice for
KD(6), misc improvements, accepted for publication in Journal of Algebra and
Its Application
Hypoxia-Inducible Factor-1α Restricts the Anabolic Actions of Parathyroid Hormone
The hypoxia inducible factors (Hifs) are evolutionarily conserved transcriptional factors that control homeostatic responses to low oxygen. In developing bone, Hif-1 generated signals induce angiogenesis necessary for osteoblast specification, but in mature bone, loss of Hif-1 in osteoblasts resulted in a more rapid accumulation of bone. These findings suggested that Hif-1 exerts distinct developmental functions and acts as a negative regulator of bone formation. To investigate the function of Hif-1α in osteoanabolic signaling, we assessed the effect of Hif-1α loss-of-function on bone formation in response to intermittent parathyroid hormone (PTH). Mice lacking Hif-1α in osteoblasts and osteocytes form more bone in response to PTH, likely through a larger increase in osteoblast activity and increased sensitivity to the hormone. Consistent with this effect, exposure of primary mouse osteoblasts to PTH resulted in the rapid induction of Hif-1α protein levels via a post-transcriptional mechanism. The enhanced anabolic response appears to result from the removal of Hif-1α-mediated suppression of β-catenin transcriptional activity. Together, these data indicate that Hif-1α functions in the mature skeleton to restrict osteoanabolic signaling. The availability of pharmacological agents that reduce Hif-1α function suggests the value in further exploration of this pathway to optimize the therapeutic benefits of PTH
Do professionals change their communication behaviours following a training in hypnosis-derived communication? : a feasibility study in pediatric oncology
Objectives
The purpose of this study was to test the feasibility of a training in hypnotic communication techniques (HCTech) for pediatric nurses to prevent procedural pain and distress in children during venipunctures. Specifically, this study aimed to (1) assess nurses’ mastery of HCTech and (2) nurses’ experience regarding the training program.
Methods
Participants were 6 female pediatric nurses and 33 of their cancer patients. Nurses took part in a 4-day theoretical and practical training in HCTech. Venipuncture procedures were video-recorded and assessed to evaluate nurses’ mastery of HCTech using a standardized scale. Pre-training use of HCTech was compared with post-training and follow-up for the entire nurse sample and across nurses with the same patients (109 nurse-patient interactions). After the follow-up, nurses were questioned about their experience in regards to the training and activities (themes and practice).
Results
Results showed medium pre-post changes in hypnotic communication behaviours (pre-post d = 0.74), with changes maintaining at follow-up (pre-follow-up d = 0.97). Interviews transcripts’ analyses revealed moderate levels of motivation and satisfaction regarding the training content and format. Nurses suggested to emphasize on the practice of HCTech in a noisy outpatient clinic as well as offer more practical exercises.
Conclusion
A 4-day training in hypnotic communication techniques translated into the use of HCTech by nurses practicing in pediatric oncology when comparing the same dyads at baseline, post-training and follow-up. Results support further refinement and suggest nurses could be trained to prevent pain and distress with hypnosis-derived communication strategies
Does practising hypnosis-derived communication techniques by oncology nurses translate into reduced pain and distress in their patients? : an exploratory study
Objectives: To explore the effects of a hypnotic communication (HC) training for
pediatric nurses in decreasing patients’ pain and distress during venipunctures. Methods: A 4-
day theoretical and practical HC training was offered to 5 pediatric oncology nurses. The
effects of HC were tested with 22 young cancer patients (13 girls, 9 boys, 10±4 years) over 4
timepoints, with 88 encounters being video-recorded and coded in stable professional-patient
dyads. Patients’ pain and distress were rated by patients and parents with visual analogue
scales and coded from recordings using the Faces, Legs, Activity, Cry and Consolability
(FLACC) scale. Results: We observed a significant decrease in pre-post distress reported by
parents (d=0.45, p=0.046). Two (out of 5) nurses with higher skills acquisition had larger
reduction in patients’ self-reported pain (d=1.03, p=0.028), parents perceived pain (d=1.09,
p=0.042), distress (d=1.05, p=0.043) as well as observed pain (d=1.22 p=0.025). Favorable
results on pain and distress did not maintain at follow-up. Conclusion and clinical
implications: Training nurses in HC may translate into improved pain and distress in patients,
both self-rated and observed provided that skills are used in practice. HC training is a
promising non-pharmacological intervention to address pain in pediatrics
Monitoring protocol to assess the overall performance of lighting and daylighting retrofit projects
In the field of lighting and daylighting, standard monitoring procedures to assess the overall performance of retrofit projects are scarce. Nevertheless the access to monitored data is crucial to assess whether daylighting or electric lighting systems deliver the expected performance in terms of cost-effectiveness and energy efficiency. In order to bridge this gap, a monitoring protocol is under development as part of the International Energy Agency – Solar Heating and Cooling Programme (IEA-SHC) Task 50 ‘Advanced Lighting Solutions for Retrofitting Buildings’. The protocol focuses on lighting and/or daylighting (façade or roof) retrofit in the non-residential building stock. It covers four key aspects: energy efficiency, costs, quality of the lighting environment
and user satisfaction. The main features of this protocol are presented in this paper, along with some lessons learned from the ongoing application on selected case studies
Comparison of Cannabinoid CB1 Receptor Binding in Adolescent and Adult Rats: A Positron Emission Tomography Study Using [18F]MK-9470
Despite the important role of cannabinoid CB1 receptors (CB1R) in brain development, little is known about their status during adolescence, a critical period for both the development of psychosis and for initiation to substance abuse. In the present study, we assessed the ontogeny of CB1R in adolescent and adult rats in vivo using positron emission tomography with [18F]MK-9470. Analysis of covariance (ANCOVA) to control for body weight that would potentially influence [18F]MK-9470 values between the two groups revealed a main effect of age (F(1,109)=5.0, P = 0.02) on [18F]MK-9470 absolute binding (calculated as percentage of injected dose) with adult estimated marginal means being higher compared to adolescents amongst 11 brain regions. This finding was confirmed using in vitro autoradiography with [3H]CP55,940 (F(10,99)=140.1, P < 0.0001). This ontogenetic pattern, suggesting increase of CB1R during the transition from adolescence to adulthood, is the opposite of most other neuroreceptor systems undergoing pruning during this period
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