1,128 research outputs found
Coherent spin rotations in open driven double quantum dots
We analyze the charge and spin dynamics in a DC biased double quantum dot
driven by crossed DC and AC magnetic fields. In this configuration, spatial
delocalization due to inter-dot tunnel competes with intra-dot spin rotations
induced by the time dependent magnetic field, giving rise to a complicated time
dependent behavior of the tunnelling current. When the Zeeman splitting has the
same value in both dots and spin flip is negligible, the electrons remain in
the triplet subspace (dark subspace) performing coherent spin rotations and the
current does not flow. This electronic trapping is removed either by finite
spin relaxation or when the Zeeman splitting is different in each quantum dot.
In the first case, our results show that measuring the current will allow to
get information on the spin relaxation time. In the last case, we will show
that applying a resonant bichromatic magnetic field, the electrons become
trapped in a coherent superposition of states and electronic transport is
blocked. Then, manipulating AC magnetic fields, electrons are driven to perform
coherent spin rotations which can be unambiguously detected by direct
measurement of the tunneling current.Comment: 7 pages, 6 figures. Extended published versio
Rare Kaon Decays Revisited
We present an updated discussion of K\ra\pi \bar{l} l decays in a combined
framework of chiral perturbation theory and Large-- QCD, which assumes the
dominance of a minimal narrow resonance structure in the invariant mass
dependence of the pair. The proposed picture reproduces very well,
both the experimental K^+\ra\pi^+ e^+ e^- decay rate and the invariant mass spectrum. The predicted Br(K_S\ra\pi^0 e^+ e^-) is, within errors,
consistent with the recently reported result from the NA48 collaboration.
Predictions for the K\ra\pi \mu^{+}\mu^{-} modes are also obtained. We find
that the resulting interference between the {\it direct} and {\it indirect}
CP--violation amplitudes in K_L\ra\pi^0 e^+ e^- is constructive
Activity of telithromycin and comparators against bacterial pathogens isolated from 1,336 patients with clinically diagnosed acute sinusitis
BACKGROUND: Increasing antimicrobial resistance among the key pathogens responsible for community-acquired respiratory tract infections has the potential to limit the effectiveness of antibiotics available to treat these infections. Since there are regional differences in the susceptibility patterns observed and treatment is frequently empirical, the selection of antibiotic therapy may be challenging. PROTEKT, a global, longitudinal multicentre surveillance study, tracks the activity of telithromycin and comparator antibacterial agents against key respiratory tract pathogens. METHODS: In this analysis, we examine the prevalence of antibacterial resistance in 1,336 bacterial pathogens, isolated from adult and paediatric patients clinically diagnosed with acute bacterial sinusitis (ABS). RESULTS AND DISCUSSION: In total, 58.0%, 66.1%, and 55.8% of S. pneumoniae isolates were susceptible to penicillin, cefuroxime, and clarithromycin respectively. Combined macrolide resistance and reduced susceptibility to penicillin was present in 200/640 (31.3 %) of S. pneumoniae isolates (128 isolates were resistant to penicillin [MIC >= 2 mg/L], 72 intermediate [MIC 0.12–1 mg/L]) while 99.5% and 95.5% of isolates were susceptible to telithromycin and amoxicillin-clavulanate, respectively. In total, 88.2%, 87.5%, 99.4%, 100%, and 100% of H. influenzae isolates were susceptible to ampicillin, clarithromycin, cefuroxime, telithromycin, and amoxicillin-clavulanate, respectively. In vitro, telithromycin demonstrated the highest activity against M. catarrhalis (MIC(50 )= 0.06 mg/L, MIC(90 )= 0.12 mg/L). CONCLUSION: The high in vitro activity of against pathogens commonly isolated in ABS, together with a once daily dosing regimen and clinical efficacy with 5-day course of therapy, suggest that telithromycin may play a role in the empiric treatment of ABS
Transformaciones de la práctica de enseñanza en educación física a partir de la Implementación del marco de la enseñanza para la comprensión
68 páginasEl presente trabajo de investigación tiene como objetivo, analizar las transformaciones de la práctica de enseñanza en educación física a partir de la implementación del marco de la enseñanza para la comprensión (EpC) en un profesor de educación básica secundaria y media. Para ello, se optó por el enfoque cualitativo, con el tipo de investigación acción pedagógica (Ávila, 2005), a través de la metodología de la Lesson Study (Pérez y Soto, 2011), para el diseño, implementación y evaluación de unidades didácticas en el marco de la EpC (Stone, 1999). En primer lugar, el profesor investigador, a través de ejercicios escritos, autoevaluó sus prácticas de enseñanza, identificándose la necesidad de mejorar los procesos de planeación, implementación de secuencias didácticas y evaluación de los aprendizajes de los estudiantes. En segundo lugar, se desarrollaron cinco ciclos de reflexión con las fases de planeación, implementación, evaluación y reflexión, relacionados con la enseñanza de los ejes y procesos para el área de Educación Física, definidos por el Ministerio de Educación Nacional y la programación institucional. Como resultados, se logró la transformación de las prácticas de enseñanza, en la medida en que la EpC permitió establecer resultados previstos de aprendizaje, actividades acordes a los procesos de desarrollo de los estudiantes e implementar acciones evaluativas que fortalecieron los procesos de aprendizaje.Maestría en PedagogíaMagíster en Pedagogí
Dimensionality Reduction of Longitudinal 'Omics Data using Modern Tensor Factorization
Precision medicine is a clinical approach for disease prevention, detection
and treatment, which considers each individual's genetic background,
environment and lifestyle. The development of this tailored avenue has been
driven by the increased availability of omics methods, large cohorts of
temporal samples, and their integration with clinical data. Despite the immense
progression, existing computational methods for data analysis fail to provide
appropriate solutions for this complex, high-dimensional and longitudinal data.
In this work we have developed a new method termed TCAM, a dimensionality
reduction technique for multi-way data, that overcomes major limitations when
doing trajectory analysis of longitudinal omics data. Using real-world data, we
show that TCAM outperforms traditional methods, as well as state-of-the-art
tensor-based approaches for longitudinal microbiome data analysis. Moreover, we
demonstrate the versatility of TCAM by applying it to several different omics
datasets, and the applicability of it as a drop-in replacement within
straightforward ML tasks
Cannabidiol (CBD): an alternative approach in gum disease management
Department of Stomatological
Propaedeutic, Pavel Godoroja, Nicolae Testemitanu State University of Medicine and
Pharmacy, Chisinau, Republic of Moldova, The 8th International Medical Congress for Students and Young Doctors, September 24-26, 2020Introduction. Periodontal diseases are one of the most common diseases in the oral cavity- as
the statistics given by the American Academy of Periodontology (AAP) suggest over fortyseven
percent (64.7 million adults) of Americans over the age of thirty suffer from severe
manifestations of periodontitis. The symptoms of periodontal disease include redness of the
gums as well as gingival inflammation, formation of periodontal pockets, and the destruction
of supporting tissue. Recent studies demonstrate that cannabidiol may have positive effects on
reducing or in some cases ceasing gum disease by its anti-inflammatory, analgesic, ability to
interact with CB2 receptors and antibacterial properties. It is necessary to demonstrate the
effects of CBD and it’s counteraction against these diseases.
Aim of the study. The effects of cannabidiol on the treatment of symptoms associated with
periodontal disease.
Materials and methods. The design of our study and the scoping review involves a systematic
exploration of various research however does not indicate an analysis of the methodological
quality of studies. This review presents an analysis of the available articles in literature by
providing a prospectus of existing content that is setting the future for research paths and pointing to the gaps within the literature. We conducted a review by applying a structured
search method in PubMed, Science Direct, LI- LACS, and SciELO.
Results. When conducting our research, we reached the conclusion that cannabidiol possesses
a positive effect on periodontal and gum diseases by reducing the pain and inflammation and
may even have an effect on preventing the disease entirely.
Conclusions. The research and statistics compiled uncovers that the benefits of cannabidiol in
treating symptoms of periodontal diseases outweigh the substance’s disadvantages. Moreover,
cannabidiol proves to have capabilities in the advancement of dental medicine by
demonstrating its potential to prevent such diseases as well as proving its worth for further
research aimed in the prevention of such diseases
A European union and Canadian review of public health nursing preparation and practice.
This study explores the preparation and role of the public health nurse (PHN) across European Union (EU) countries (Finland, Sweden, and the United Kingdom) and Canadian provinces (Alberta, New Brunswick, and Prince Edward Island)
- …