225 research outputs found
Review: Management of midshaft clavicle fractures in adolescents
Clavicle fractures are common injuries that occur across all age ranges, but are largely seen in young, active males. The majority of these fractures (70-80%) occur in the midshaft of the clavicle. The purpose of this review was to compare non-operative treatment to operative treatment of midclavicular fractures and determine whether treatment for adolescent clavicle fractures more closely aligns with pediatric or adult management. Adolescent clavicle fractures are increasingly treated with open reduction and internal fixation, especially in the 15 to 19 age group. Nevertheless, there remains a lack of high-level studies comparing outcomes of operative and conservative treatment specifically for the adolescent population to justify this recent trend. These findings expose the need for a prospective study to provide a framework for treatment, and they suggest that physicians have become overaggressive in their management of mid-shaft clavicle fractures in adolescents
Phase-Resolved Rydberg Atom Field Sensing using Quantum Interferometry
Although Rydberg atom-based electric field sensing provides key advantages
over traditional antenna-based detection, it remains limited by the need for a
local oscillator (LO) for low-field and phase resolved detection. In this work,
we demonstrate that closed-loop quantum interferometric schemes can be used to
generate a system-internal reference that can directly replace an external LO
for Rydberg field sensing. We reveal that this quantum-interferometrically
defined internal reference phase and frequency can be used analogously to a
traditional LO for atom-based down-mixing to an intermediate frequency for
lock-in phase detection. We demonstrate that this LO-equivalent functionality
provides analogous benefits to an LO, including full 360 phase
resolution as well as improved sensitivity. The general applicability of this
approach is confirmed by demodulating a four phase-state signal broadcast on
the atoms. Our approach opens up new sensing schemes and provides a clear path
towards all-optical Rydberg atom sensing implementations
Reduced prefrontal and temporal processing and recall of high sensation value ads
Public service announcements (PSAs) are non-commercial broadcast ads that are an important part of televised public health campaigns. âMessage sensation valueâ (MSV), a measure of sensory intensity of audio, visual, and content features of an ad, is an important factor in PSA impact. Some communication theories propose that higher message sensation value brings increased attention and cognitive processing, leading to higher ad impact. Others argue that the attention-intensive format could compete with ad\u27s message for cognitive resources and result in reduced processing of PSA content and reduced overall effectiveness. Brain imaging during PSA viewing provides a quantitative surrogate measure of PSA impact and addresses questions of PSA evaluation and design not accessible with traditional subjective and epidemiological methods. We used Blood Oxygenation Level Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) and recognition memory measures to compare high and low MSV anti-tobacco PSAs and neutral videos. In a short-delay, forced-choice memory test, frames extracted from PSAs were recognized more accurately than frames extracted from the NV. Frames from the low MSV PSAs were better recognized than frames from the high MSV PSAs. The accuracy of recognition of PSA frames was positively correlated with the prefrontal and temporal, and negatively correlated with the occipital cortex activation. The low MSV PSAs were associated with greater prefrontal and temporal activation, than the high MSV PSAs. The high MSV PSAs produced greater activation primarily in the occipital cortex. These findings support the âdual processingâ and âlimited capacityâ theories of communication that postulate a competition between ad\u27s content and format for the viewers\u27 cognitive resources and suggest that the âattention-grabbingâ high MSV format could impede the learning and retention of an ad. These findings demonstrate the potential of using neuroimaging in the design and evaluation of mass media public health communications
Detection of HF and VHF Fields through Floquet Sideband Gaps by `Rabi Matching' Dressed Rydberg Atoms
Radio frequencies in the HF and VHF (3 MHz to 300 MHz) bands are challenging
for Rydberg atom-based detection schemes, as resonant detection requires
exciting the atoms to extremely high energy states. We demonstrate a method for
detecting and measuring radio frequency (RF) carriers in the HF and VHF bands
via a controlled Autler-Townes line splitting. Using a resonant, high-frequency
(GHz) RF field, the absorption signal from Townes-Merrit sidebands created by a
low frequency, non-resonant RF field can be enhanced. Notably, this technique
uses a measurement of the optical frequency separation of an avoided crossing
to determine the amplitude of a non-resonant, low frequency RF field. This
technique also provides frequency-selective measurements of low frequency RF
electric fields. To show this, we demonstrate amplitude modulated signal
transduction on a low frequency VHF carrier. We further demonstrate reception
of multiple tones simultaneously, creating a Rydberg `spectrum analyzer' over
the VHF range.Comment: Data for figures can be found at:
https://datapub.nist.gov/od/id/mds2-285
Sensitivity Comparison of Two-photon vs Three-photon Rydberg Electrometry
We investigate the sensitivity of three-photon EIT in Rydberg atoms to radio
frequency detection and compare it against conventional two-photon systems.
Specifically, we model the 4-level and 5-level atomic system and compare how
the transmission of the probe changes with different powers of the lasers used
and strengths of the RF field. In this model, we also define a sensitivity
metric to best relate to the operation of the current best experimental
implementation based on shot noise limited detection. We find that the
three-photon system boasts much narrower line widths compared to the
conventional two-photon EIT. However, these narrow line features do not align
with the regions of the best sensitivity. In addition to this, we calculate the
expected sensitivity for the two-photon Rydberg sensor and find that the best
achievable sensitivity is over an order of magnitude better than the current
measured values of 5 uV/m/Hz. However, by accounting for the additional noise
sources in the experiment and the quantum efficiency of the photo-detectors,
the values are in good agreement.Comment: 9 pages, 6 figure
Occupy: in theory and practice
This paper situates the discourse of the Occupy movement within the context of radical political philosophy. Our analysis takes place on two levels. First, we conduct an empirical analysis of the âofficialâ publications of Occupy Wall Street (OWS) and Occupy London (OL). Operationalising core concepts from the framing perspective within social movement theory, we provide a descriptive-comparative analysis of the âcollective action framesâ of OWS and OL. Second, we consider the extent to which radical political philosophy speaks to the discourse of Occupy. Our empirical analysis reveals that both movements share diagnostic frames, but there were notable differences in terms of prognostic framing. The philosophical discussion suggests that there are alignments between anarchist, post-anarchist and post-Marxist ideologies at the level of both identity and strategy. Indeed, the absence of totalising anti-capitalist or anti-statist positions in Occupy suggests that â particularly with Occupy London â alignments are perhaps not so distant from typically social democratic demands
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Validation of GPM IMERG extreme precipitation in the peninsular Malaysia and Philippines by station and radar data
Abstract: Extreme precipitation is ubiquitous in the Maritime Continent (MC) but poorly predicted numerical weather prediction (NWP) models. NWP evaluation against accurate measures of heavy precipitation is essential to improve their forecasting skill. Here we examine the potential utility of the Global Precipitation Measurement (GPM) Integrated Multi-Satellite Retrieval for GPM (IMERG) for NWP evaluation of extreme precipitation in the MC. For that purpose, we use radar data in Subang (Malaysia) and station data from the Global Historical Climatology Network (GHCN) in Malaysia and the Philippines. We find that earlier studies may have underestimated IMERG performances in the MC due to large spatial sampling errors of ground precipitation measurements, especially during extreme precipitation conditions. We recommend using the 95th percentile for NWP evaluation of extreme daily and sub-daily precipitation against IMERG. At higher percentiles, the IMERG rainfall rates tend to diverge from ground observation and may therefore be treated with caution
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A high-resolution map of human evolutionary constraint using 29 mammals.
The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering âŒ4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for âŒ60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease
Extensive Evolutionary Changes in Regulatory Element Activity during Human Origins Are Associated with Altered Gene Expression and Positive Selection
Understanding the molecular basis for phenotypic differences between humans and other primates remains an outstanding challenge. Mutations in non-coding regulatory DNA that alter gene expression have been hypothesized as a key driver of these phenotypic differences. This has been supported by differential gene expression analyses in general, but not by the identification of specific regulatory elements responsible for changes in transcription and phenotype. To identify the genetic source of regulatory differences, we mapped DNaseI hypersensitive (DHS) sites, which mark all types of active gene regulatory elements, genome-wide in the same cell type isolated from human, chimpanzee, and macaque. Most DHS sites were conserved among all three species, as expected based on their central role in regulating transcription. However, we found evidence that several hundred DHS sites were gained or lost on the lineages leading to modern human and chimpanzee. Species-specific DHS site gains are enriched near differentially expressed genes, are positively correlated with increased transcription, show evidence of branch-specific positive selection, and overlap with active chromatin marks. Species-specific sequence differences in transcription factor motifs found within these DHS sites are linked with species-specific changes in chromatin accessibility. Together, these indicate that the regulatory elements identified here are genetic contributors to transcriptional and phenotypic differences among primate species
A High-Resolution Map of Human Evolutionary Constraint Using 29 Mammals
The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering ~4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for ~60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease.National Human Genome Research Institute (U.S.)National Institute of General Medical Sciences (U.S.) (Grant number GM82901)National Science Foundation (U.S.). Postdoctural Fellowship (Award 0905968)National Science Foundation (U.S.). Career (0644282)National Institutes of Health (U.S.) (R01-HG004037)Alfred P. Sloan Foundation.Austrian Science Fund. Erwin Schrodinger Fellowshi
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