63 research outputs found
A global model of recovery and rebalancing
pre-printThis paper presents an investigation of global recovery from the great recession and rebalancing of global external imbalances, using a global model of sixteen countries and composite regions. The model applies to the short run, and only to the real side. Key features are demand-driven output determination, pro-cyclical aggregate labor productivity, imperfect competition in product markets and simple bargaining in non-clearing labor markets, which together determine the functional distribution of income. Trade is modeled in a bilateral import matrix; particular attention is paid to international adjustment. Simulation results suggest that early exit from fiscal support threatens a fragile recovery. Further, domestic demand expansion and revaluation in real terms in surplus countries are necessary for rebalancing, and a variety of measures can be employed to achieve these goals
The Allen Telescope Array Twenty-centimeter Survey -- A 700-Square-Degree, Multi-Epoch Radio Dataset -- II: Individual Epoch Transient Statistics
We present our second paper on the Allen Telescope Array Twenty-centimeter
Survey (ATATS), a multi-epoch, ~700 sq. deg. radio image and catalog at 1.4
GHz. The survey is designed to detect rare, bright transients as well as to
commission the ATA's wide-field survey capabilities. ATATS explores the
challenges of multi-epoch transient and variable source surveys in the domain
of dynamic range limits and changing (u,v) coverage.
Here we present images made using data from the individual epochs, as well as
a revised image combining data from all ATATS epochs. The combined image has
RMS noise 3.96 mJy / beam, with a circular beam of 150 arcsec FWHM. The
catalog, generated using a false detection rate algorithm, contains 4984
sources, and is >90% complete to 37.9 mJy. The catalogs generated from snapshot
images of the individual epochs contain between 1170 and 2019 sources over the
564 sq. deg. area in common to all epochs. The 90% completeness limits of the
single epoch catalogs range from 98.6 to 232 mJy.
We compare the catalog generated from the combined image to those from
individual epochs, and from the NRAO VLA Sky Survey (NVSS), a legacy survey at
the same frequency. We are able to place new constraints on the transient
population: fewer than 6e-4 transients / sq. deg., for transients brighter than
350 mJy with characteristic timescales of minutes to days. This strongly rules
out an astronomical origin for the ~1 Jy sources reported by Matsumura et al.
(2009), based on their stated rate of 3.1e-3 / sq. deg.Comment: 28 pages, 12 figures, ApJ accepte
The Role of Action Potential Waveform in Failure of Excitation Contraction Coupling
Excitation contraction coupling (ECC) is the process by which electrical excitation of muscle is converted into force generation. Depolarization of skeletal muscle resting potential contributes to failure of ECC in diseases such as periodic paralysis, ICU acquired weakness and possibly fatigue of muscle during vigorous exercise. When extracellular K+ is raised to depolarize the resting potential, failure of ECC occurs suddenly, over a range of several mV of resting potential. While some studies have hypothesized the sudden failure of ECC is due to all-or-none failure of excitation, other studies suggest failure of excitation is graded. Intracellular recordings of action potentials (APs) in individual fibers during depolarization revealed that APs do not fail in an all-or-none manner. Simultaneous imaging of Ca2+ transients during depolarization revealed failure over a narrow range of resting potentials. An AP property that closely correlated with the sudden failure of the Ca2+ transient was the integral of AP voltage with respect to time. We hypothesize the close correlation is due to the combined dependence on time and voltage of Ca2+ release from the sarcoplasmic reticulum. The quantitative relationships established between resting potential, APs and Ca2+ transients provide the foundation for future studies of depolarization-induced failure of ECC in diseases such as periodic paralysis
Causes of the Antarctic region record high temperature at Signy Island, 30 January 1982
On 30th January 1982, the research station on Signy Island (South Orkney Islands) reported a daily maximum temperature of 19.8 °C. This is a record maximum for any station south of 60°S. We use surface observations, atmospheric reanalyses and high-resolution atmospheric model simulations to investigate the drivers of this extreme event. At the time of the record temperature exceptionally warm air was being advected southwards towards the South Orkney Islands from the subtropical South Atlantic. This air mass cooled significantly at levels below 1 km during its long track over the cold Southern Ocean but remained relatively warm above this level. Atmospheric model simulations show that warm air from upper levels was brought down towards the surface over Signy Island in a föhn wind generated by northerly flow over Coronation Island, a mountainous island just to the north of Signy Island. Modelled temperatures over Signy Island are in good agreement with observations and thus support the hypothesis that the record temperature was caused by a combination of exceptional warm advection with conditions suitable for the generation of föhn. Since conditions conducive to föhn occur relatively frequently, föhn warming may have a significant influence on the local climate and ecology of Signy Island
Extreme temperatures in the Antarctic
We present the first Antarctic-wide analysis of extreme near-surface air temperatures based on data collected up to the end of 2019 as part of the synoptic meteorological observing programs. We consider temperatures at 17 stations on the Antarctic continent and nearby sub-Antarctic islands. We examine the frequency distributions of temperatures and the highest and lowest individual temperatures observed. The variability and trends in the number of extreme temperatures were examined via the mean daily temperatures computed from the 0, 6, 12 and 18 UTC observations, with the thresholds for extreme warm and cold days taken as the 5th and 95th percentiles. The five stations examined from the Antarctic Peninsula region all experienced a statistically significant increase (p < 0.01) in the number of extreme high temperatures in the late Twentieth Century part of their records, although the number of extremes decreased in subsequent years. For the period after 1979 we investigate the synoptic background to the extreme events using ECMWF ERA-Interim reanalysis fields. The majority of record high temperatures were recorded after the passage of airmasses over high orography, with the air being warmed by the Föhn effect. At some stations in coastal East Antarctica the highest temperatures were recorded after air with a high potential temperature descended from the Antarctic plateau, resulting in an airmass 5-7°C warmer than the maritime air. Record low temperatures at the Antarctic Peninsula stations were observed during winters with positive sea ice anomalies over the Bellingshausen and Weddell Seas
Development and Assessment of a Diagnostic DNA Oligonucleotide Microarray for Detection and Typing of Meningitis-Associated Bacterial Species.
Meningitis is commonly caused by infection with a variety of bacterial or viral pathogens. Acute bacterial meningitis (ABM) can cause severe disease, which can progress rapidly to a critical life-threatening condition. Rapid diagnosis of ABM is critical, as this is most commonly associated with severe sequelae with associated high mortality and morbidity rates compared to viral meningitis, which is less severe and self-limiting. We have designed a microarray for detection and diagnosis of ABM. This has been validated using randomly amplified DNA targets (RADT), comparing buffers with or without formamide, in glass slide format or on the Alere ArrayTubeTM (Alere Technologies GmbH) microarray platform. Pathogen-specific signals were observed using purified bacterial nucleic acids and to a lesser extent using patient cerebral spinal fluid (CSF) samples, with some technical issues observed using RADT and glass slides. Repurposing the array onto the Alere ArrayTubeTM platform and using a targeted amplification system increased specific and reduced nonspecific hybridization signals using both pathogen nucleic and patient CSF DNA targets, better revealing pathogen-specific signals although sensitivity was still reduced in the latter. This diagnostic microarray is useful as a laboratory diagnostic tool for species and strain designation for ABM, rather than for primary diagnosis
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Mixed-methods formative evaluation of implementing an adapted suicide prevention treatment: Dialectical Behavior Therapy Skills Groups in the Veterans Health Administration.
BACKGROUND: Preventing veteran suicide requires addressing mechanisms driving suicidal behavior, such as emotion dysregulation. Dialectical Behavior Therapy Skills Groups (DBT-SG) are well established for reducing emotion dysregulation, improving coping skills, and in some studies, reducing suicide attempt, but will require implementation support to deliver DBT-SG and to test its effectiveness within the Veterans Health Administration (VHA). METHODS: We conducted a mixed-method developmental formative evaluation of DBT-SG at four VHA medical centers, guided by the Integrated Promoting Action on Research Implementation in Health Services (i-PARIHS) framework, as part of a hybrid effectiveness-implementation trial (Clinical trials ID, NCT05000749). RESULTS: Quantitative Organizational Reasons for Change Assessment data (n = 30 VHA staff) and qualitative data (n = 35 VHA staff) were merged, compared, and triangulated. Quantitative and qualitative data largely converged, showing favorable views of evidence supporting DBT-SG and strong enthusiasm for its potential to reduce veteran suicide attempt. Staff noted DBT-SGs broad applicability to veterans. Staff were less optimistic about the inner context supporting DBT-SG implementation, commenting on how limited staffing could be a barrier despite leadership wanting to support suicide prevention. CONCLUSIONS: Implementation barriers to DBT-SG at VHA include limited staffing, despite staff enthusiasm. The next phase of this project will evaluate DBT-SG effectiveness in a randomized controlled trial. CLINICAL TRIALS REGISTRATION: https://clinicaltrials.gov/study/NCT05000749, identifier NCT05000749
Facile one-spot synthesis of highly branched polycaprolactone
Reported is the first solvent-free (bulk) synthesis of degradable/bioresorbable, highly branched polymers via tin octanoate Sn(Oct2) catalysed controlled ring opening co-polymerisation (ROP) of mono and di-functional lactone monomers that proceed to near quantitative conversion. The successful isolation of solvent soluble, highly branched structures was shown to be dependent on both the concentration of the di-functional monomer and the overall reaction time. Comparison with analogous systems utilising controlled radical polymerisation (CRP) to form the highly/hyper branched polymers suggested significant experimental differences between the two chain growth methods. The maximum proportion of di-functional monomer without gelation ensuing was found to be 0.6 equivalents w.r.t. mono-functional monomer (c.f. 1 with CRP) and the onset of significant levels of branching occurred at approximately 90% conversion (c.f. ~70% with CRP). These differences and significant disparity in reaction times were attributed to (a) the coordination and insertion (C+I) propagation mechanism adopted by the Sn catalyst and (b) the presence of additional trans-esterification reactions at high conversion. Evidence is presented to support the conclusion that there are two mechanisms contributing to the overall branching process in the ROP system at high conversion. First, the C+I mechanism promotes growth of linear polymer until approximately 90% conversion, after which both the C+I and trans-esterification processes contribute to the interchain branching process. The branched nature of the molecular structures was supported by confirmation plots generated from static light scattering. This data demonstrated that the polymers synthesised exhibit varying degrees of branching, consistent with the di-functional monomer (4,4’-bioxepanyl-7,7’-dione - BOD) concentration in the feed. The degree of branching was calculated using 3 different methods and the results were shown to be independent of method. Finally, DSC analysis of the polymers demonstrated correlation between the degree of branching achieved and the observed Tm for the material where increased branching leads to a drop in the recorded Tm
Effectiveness of EDACS Versus ADAPT Accelerated Diagnostic Pathways for Chest Pain: A Pragmatic Randomized Controlled Trial Embedded Within Practice
Study objective
A 2-hour accelerated diagnostic pathway based on the Thrombolysis in Myocardial Infarction score, ECG, and troponin measures (ADAPT-ADP) increased early discharge of patients with suspected acute myocardial infarction presenting to the emergency department compared with standard care (from 11% to 19.3%). Observational studies suggest that an accelerated diagnostic pathway using the Emergency Department Assessment of Chest Pain Score (EDACS-ADP) may further increase this proportion. This trial tests for the existence and size of any beneficial effect of using the EDACS-ADP in routine clinical care.
Methods
This was a pragmatic randomized controlled trial of adults with suspected acute myocardial infarction, comparing the ADAPT-ADP and the EDACS-ADP. The primary outcome was the proportion of patients discharged to outpatient care within 6 hours of attendance, without subsequent major adverse cardiac event within 30 days.
Results
Five hundred fifty-eight patients were recruited, 279 in each arm. Sixty-six patients (11.8%) had a major adverse cardiac event within 30 days (ADAPT-ADP 29; EDACS-ADP 37); 11.1% more patients (95% confidence interval 2.8% to 19.4%) were identified as low risk in EDACS-ADP (41.6%) than in ADAPT-ADP (30.5%). No low-risk patients had a major adverse cardiac event within 30 days (0.0% [0.0% to 1.9%]). There was no difference in the primary outcome of proportion discharged within 6 hours (EDACS-ADP 32.3%; ADAPT-ADP 34.4%; difference −2.1% [−10.3% to 6.0%], P=.65).
Conclusion
There was no difference in the proportion of patients discharged early despite more patients being classified as low risk by the EDACS-ADP than the ADAPT-ADP. Both accelerated diagnostic pathways are effective strategies for chest pain assessment and resulted in an increased rate of early discharges compared with previously reported rates
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A 19-SNP coronary heart disease gene score profile in subjects with type 2 diabetes: the coronary heart disease risk in type 2 diabetes (CoRDia study) study baseline characteristics
Background
The coronary risk in diabetes (CoRDia) trial (n = 211) compares the effectiveness of usual diabetes care with a self-management intervention (SMI), with and without personalised risk information (including genetics), on clinical and behavioural outcomes. Here we present an assessment of randomisation, the cardiac risk genotyping assay, and the genetic characteristics of the recruits.
Methods
Ten-year coronary heart disease (CHD) risk was calculated using the UKPDS score. Genetic CHD risk was determined by genotyping 19 single nucleotide polymorphisms (SNPs) using Randox’s Cardiac Risk Prediction Array and calculating a gene score (GS). Accuracy of the array was assessed by genotyping a subset of pre-genotyped samples (n = 185).
Results
Overall, 10-year CHD risk ranged from 2–72 % but did not differ between the randomisation groups (p = 0.13). The array results were 99.8 % concordant with the pre-determined genotypes. The GS did not differ between the Caucasian participants in the CoRDia SMI plus risk group (n = 66) (p = 0.80) and a sample of UK healthy men (n = 1360). The GS was also associated with LDL-cholesterol (p = 0.05) and family history (p = 0.03) in a sample of UK healthy men (n = 1360).
Conclusions
CHD risk is high in this group of T2D subjects. The risk array is an accurate genotyping assay, and is suitable for estimating an individual’s genetic CHD risk.
Trial registration
This study has been registered at ClinicalTrials.gov; registration identifier NCT0189178
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