9,122 research outputs found
Interacting Dark Energy: Possible Explanation for 21-cm Absorption at Cosmic Dawn
A recent observation points to an excess in the expected 21-cm brightness
temperature from cosmic dawn. In this paper, we present an alternative
explanation of this phenomenon, an interaction in the dark sector. Interacting
dark energy models have been extensively studied recently and there is a whole
variety of such in the literature. Here we particularize to a specific model in
order to make explicit the effect of an interaction.Comment: 5 pages, 2 figures. Discussion improved, new references, conclusions
unchanged. Accepted in EPJ
(2+1) Resonance Enhanced Ionization Spectroscopy of a State Selected Beam of OH Radicals
A state-selected beam of hydroxyl radicals is generated using a pulsed discharge source and hexapole field. The OH radicals are characterized by resonance-enhanced multiphoton ionization (REMPI) spectroscopy via the nested Dā and 3ā Rydberg states. Simplified spectra are observed from the selected ā£MJā£ = 3/2 component of the upper Ī-doublet level of the lowest rotational state (J = 3/2) in ground (vā³ = 0) and excited(vā³ = 1ā3) vibrational levels of the OH Xā state. Two-photon transitions are observed to the Dā(vā² = 0ā3) and 3ā(vā² = 0,1) vibronic levels, extending previous studies to higher vibrational levels of the Rydberg states. Spectroscopic constants are derived for the Rydberg states and compared with prior experimental studies. Complementary first-principle theoretical studies of the Dā and 3ā Rydberg states [see M. P. J. van der Loo and G. C. Groenenboom, J. Chem. Phys. 123, 074310 (2005), following paper ] are used to interpret the experimental findings and examine the utility of the (2+1) REMPI scheme for sensitive detection of OH radicals
Ultrafast Resonant Polarization Interferometry: Towards the First Direct Detection of Vacuum Polarization
Vacuum polarization, an effect predicted nearly 70 years ago, is still yet to
be directly detected despite significant experimental effort. Previous attempts
have made use of large liquid-helium cooled electromagnets which inadvertently
generate spurious signals that mask the desired signal. We present a novel
approach for the ultra-sensitive detection of optical birefringence that can be
usefully applied to a laboratory detection of vacuum polarization. The new
technique has a predicted birefringence measurement sensitivity of in a 1 second measurement. When combined with the extreme
polarizing fields achievable in this design we predict that a vacuum
polarization signal will be seen in a measurement of just a few days in
duration.Comment: 9 pages, 2 figures. submitted to PR
Greek-Letter Membership and College Graduation: Does Race Matter?
Research, utilizing a nationally representative sample of 3,712 Americans, revealed that Greek-letter membership increases the probability of college graduation more for African Americans than for European Americans. Conversely, father\u27s education is a more robust predictor of educational outcomes for European Americans compared to their African American counterpart
Deep learning techniques applied to skin lesion classification: a review
Skin cancer is one of the most common cancers in the world. The most dangerous type of skin cancer is melanoma, which can be lethal if not treated early. However, diagnosing skin lesions can be a difficult task. Therefore, deep learning techniques applied to the diagnosis of skin lesions have been explored by researchers, given their effectiveness in extracting features and classifying input data. In this work, we present a review of latest approaches that apply deep learning techniques to skin lesion classification task. In addition, some datasets used for training and validating the models are introduced, informing their characteristics and specificities, as well as popular pre-processing steps and skin lesion segmentation approaches. Finally, we comment the effectiveness of the proposed models.info:eu-repo/semantics/publishedVersio
The Parallel Encounter: An Alternative to the Traditional Serial TraineeāAttending Patient Evaluation Model
BackgroundThe emergency department environment requires the clinicianāeducator to use adaptive teaching strategies to balance education with efficiency and patient care. Recently, alternative approaches to the traditional serial traineeāattending patient evaluation model have emerged in the literature.MethodsThe parallel encounter involves the attending physician and resident seeing the patient independently. Instead of the trainee delivering a traditional oral case presentation, the trainee does not present the history and examination to the attending physician. Rather, the attending and trainee come together following their independent evaluations to jointly discuss and formulate the assessment and plan.ResultsThe parallel encounter has the potential to enhance the teaching encounter by emphasizing clinical reasoning, reduce cognitive bias by integrating two independent assessments of the same patient, increase attending workflow flexibility and efficiency, and improve patient satisfaction and outcomes by reducing time to initial provider contact. The attending must be mindful of protecting resident autonomy. This model tends to work better for more senior learners.ConclusionsThe parallel encounter represents a novel approach to the traditional serial traineeāattending patient evaluation model that may enhance the teaching encounter and improve patient care.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163487/2/aet210491_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163487/1/aet210491.pd
Photodissociation of the OD radical at 226 and 243 nm
The photodissociation dynamics of state selected OD radicals has been examined at 243 and 226 nm using velocity map imaging to probe the angleāspeed distributions of theD(2S) and O(3P2) products. Both experiment and complementary first principle calculations demonstrate that photodissociation occurs by promotion of OD from high vibrational levels of the ground Xā2Ī state to the repulsive 1ā2Ī£ā state
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Treatment of hospital-acquired pneumonia with linezolid or vancomycin: a systematic review and meta-analysis
Objective: Hospital-acquired pneumonia remains the most lethal and expensive nosocomial infection worldwide. Optimal therapy remains controversial. We aimed to compare mortality and clinical response outcomes in patients treated with either linezolid or vancomycin. Design: Systematic review and meta-analysis. Data sources PubMed, EMBASE, Cochrane Library, American College of Physicians Journal Club, Evidence-based Medicine BMJ and abstracts from infectious diseases and critical care meetings were searched through April 2013. Eligibility criteria for selecting studies All randomised clinical trials comparing linezolid to vancomycin for hospital-acquired pneumonia. Data extraction Preferred reporting items for systematic reviews and meta-analyses guidelines were followed. One author extracted the data and two authors rechecked and verified all data. Results: Nine randomised trials with a total of 4026 patients were included. The adjusted absolute mortality risk difference (RD) between linezolid and vancomycin was 0.01% (95% CI ā2.1% to 2.1%; p=0.992; I2=13.5%. The adjusted absolute clinical response difference was 0.9% (95% CI ā1.2% to 3.1%; p=0.409; I2=0%. The risk of both microbiological (RD=5.6%, 95% CI ā2.2% to 13.3%; p=0.159; I2=0%) and methicillin-resistant Staphylococcus aureus (RD=6.4%, 95% CI ā4.1% to 16.9%; p=0.230; I2=0%) eradication were not different between linezolid and vancomycin. Gastrointestinal side effects were more frequent with linezolid (RD=0.8% (95% CI 0% to 1.5%; p=0.05), but no differences were found with renal failure, thrombocytopenia and drug discontinuation due to adverse events. Our sample size provided 99.9% statistical power to detect differences between drugs regarding clinical response and mortality. Conclusions: Linezolid and vancomycin have similar efficacy and safety profiles. The high statistical power and the near-zero efficacy difference between both antibiotics demonstrates that no drug is superior for the treatment of hospital-acquired pneumonia
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MyBrush: Brushing and Linking with Personal Agency
We extend the popular brushing and linking technique by incorporating personal agency in the interaction. We map existing research related to brushing and linking into a design space that deconstructs the interaction technique into three components: source (what is being brushed), link (the expression of relationship between source and target), and target (what is revealed as related to the source). Using this design space, we created MyBrush, a unified interface that offers personal agency over brushing and linking by giving people the flexibility to configure the source, link, and target of multiple brushes. The results of three focus groups demonstrate that people with different backgrounds leveraged personal agency in different ways, including performing complex tasks and showing links explicitly. We reflect on these results, paving the way for future research on the role of personal agency in information visualization
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