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To define optimal thromboprophylaxis strategy after stent implantation in superior or total cavopulmonary connections.
Stent thrombosis is a rare complication of intravascular stenting, with a perceived higher risk in single-ventricle patients.
All patients who underwent stent implantation within superior or total cavopulmonary connections (caval vein, innominate vein, Fontan, or branch pulmonary arteries) were included. Cohort was divided into aspirin therapy alone versus advanced anticoagulation, including warfarin, enoxaparin, heparin, or clopidogrel. Primary endpoint was in-stent or downstream thrombus, and secondary endpoints included bleeding complications.
A total of 58 patients with single-ventricle circulation underwent 72 stent implantations. Of them 14 stents (19%) were implanted post-superior cavopulmonary connection and 58 (81%) post-total cavopulmonary connection. Indications for stenting included vessel/conduit stenosis (67%), external compression (18%), and thrombotic occlusion (15%). Advanced anticoagulation was prescribed for 32 (44%) patients and aspirin for 40 (56%) patients. Median follow up was 1.1 (25th–75th percentile, 0.5–2.6) years. Echocardiograms were available in 71 patients (99%), and advanced imaging in 44 patients (61%). Thrombosis was present in two patients on advanced anticoagulation (6.3%) and none noted in patients on aspirin (p = 0.187). Both patients with in-stent thrombus underwent initial stenting due to occlusive left pulmonary artery thrombus acutely post-superior cavopulmonary connection. There were seven (22%) significant bleeding complications for advanced anticoagulation and none for aspirin (p < 0.001).
Antithrombotic strategy does not appear to affect rates of in-stent thrombus in single-ventricle circulations. Aspirin alone may be sufficient for most patients undergoing stent implantation, while pre-existing thrombus may warrant advanced anticoagulation.
Our knowledge of the universe comes from recording the photon and particle fluxes incident on the Earth from space. We thus require sensitive measurement across the entire energy spectrum, using large telescopes with efficient instrumentation located on superb sites. Technological advances and engineering constraints are nearing the point where we are recording as many photons arriving at a site as is possible. Major advances in the future will come from improving the quality of the site. The ultimate site is, of course, beyond the Earth’s atmosphere, such as on the Moon, but economic limitations prevent our exploiting this avenue to the degree that the scientific community desires. Here we describe an alternative, which offers many of the advantages of space for a fraction of the cost: the Antarctic Plateau.
Due to the wide bandgap and other key materials properties of 4H-SiC, SiC MOSFETs
offer performance advantages over competing Si-based power devices. For example,
SiC can more easily be used to fabricate MOSFETs with very high voltage ratings,
and with lower switching losses. Silicon carbide power MOSFET development has
progressed rapidly since the market release of Cree’s 1200V 4H-SiC
power MOSFET in 2011. This is due to continued advancements in SiC substrate
quality, epitaxial growth capabilities, and device processing. For example,
high-quality epitaxial growth of thick, low-doped SiC has enabled the
fabrication of SiC MOSFETs capable of blocking extremely high voltages (up to
15kV); while dopant control for thin highly-doped epitaxial layers has helped
enable low on-resistance 900V SiC MOSFET production. Device design and
processing improvements have resulted in lower MOSFET specific on-resistance for
each successive device generation. SiC MOSFETs have been shown to have a long
device lifetime, based on the results of accelerated lifetime testing, such as
high-temperature reverse-bias (HTRB) stress and time-dependent dielectric
Field experiments were conducted at two locations in Missouri in 2012 and 2013 to evaluate herbicide programs in 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitor-resistant soybean, referred to as FG72 soybean, and their tolerance to four HPPD-inhibiting herbicides. At the Columbia location, PRE followed by (fb) POST and two-pass POST treatments provided 97% or greater control of all weeds except ivyleaf morningglory. At Moberly in 2012, PRE fb POST treatments provided 95% or greater control and 100% biomass reduction (BR) of glyphosate-resistant (GR) waterhemp, with the exception of isoxaflutole at 0.04 kg ha−1 plus S-metolachlor at 0.6 kg ha−1 plus metribuzin at 0.2 kg ha−1. In 2013, PRE fb POST treatments provided greater than 89% control and 93% BR. Two-pass POST treatments of isoxaflutole plus glyphosate always provided greater control and BR of GR waterhemp compared with glyphosate fb glyphosate. However, at Columbia, where glyphosate-susceptible weeds were present, there were no differences in control or BR between two-pass POST treatments. In the soybean tolerance experiment, isoxaflutole provided the lowest levels of injury. Applications of tembotrione at the 1× rate resulted in the greatest injury in both years. Topramezone at the 1× rate always provided less injury than tembotrione, but was always similar in BR. The 2× rates increased soybean injury over the 1× rate for the third trifoliate (V3) application, but not for the PRE and first-flower (R1) applications. V3 and R1 applications of isoxaflutole and mesotrione resulted in similar injury, height reduction, and BR to soybean 28 d after application in 2012 and 2013. Overall these results indicate that FG72 soybean could allow the use of HPPD-inhibiting herbicides such as mesotrione PRE along with isoxaflutole PRE and POST to provide an additional herbicide mechanism of action that was not previously available in soybean.
Surgical site infection (SSI) surveillance is performed using a variety of methods with unclear performance characteristics. We used claims data to identify records for review following hysterectomy and colorectal surgery. Claims-enhanced screening identified SSIs missed by routine surveillance and could be used for targeted chart review to improve SSI detection.
We describe the specifications, characteristics, calibration, and analysis of data from the University of New South Wales Infrared Fabry–Perot (UNSWIRF) etalon. UNSWIRF is a near-infrared tunable imaging spectrometer, used primarily in conjunction with IRIS on the AAT, but suitable for use as a visitor instrument at other telescopes. The etalon delivers a resolving power in excess of 4000 (corresponding to a velocity resolution ∼75 km s−1), and allows imaging of fields up to 100″ in diameter on the AAT at any wavelength between 1·5 and 2·4 μm for which suitable blocking filters are available.
To assess the ability of Medicare claims to identify US hospitals with high rates of surgical site infection (SSI) after hip arthroplasty.
Retrospective cohort study.
Acute care US hospitals.
Fee-for-service Medicare patients 65 years of age and older who underwent hip arthroplasty in US hospitals from 2005 through 2007.
Hospital rankings were derived from claims codes suggestive of SSI, adjusted for age, sex, and comorbidities, while using generalized linear mixed models to account for hospital volume. Medical records were obtained for validation of infection on a random sample of patients from hospitals ranked in the best and worst deciles of performance. We then calculated the risk-adjusted odds of developing a chart-confirmed SSI after hip arthroplasty in hospitals ranked by claims into worst- versus best-performing deciles.
Among 524,892 eligible Medicare patients who underwent hip arthroplasty at 3,296 US hospitals, a patient who underwent surgery in a hospital ranked in the worst-performing decile based on claims-based evidence of SSI had 2.9-fold higher odds of developing a chart-confirmed SSI relative to a patient with the same age, sex, and comorbidities in a hospital ranked in the best-performing decile (95% confidence interval, 2.2-3.7).
Medicare claims successfully distinguished between hospitals with high and low SSI rates following hip arthroplasty. These claims can identify potential outlier hospitals that merit further evaluation. This strategy can also be used to validate the completeness of public reporting of SSI.
We use nonparametric production function methods to decompose farm-level labor productivity growth into components attributable to efficiency change, technical change, and factor intensity. The estimation is accomplished using balanced panel data drawn from the Kansas Farm Management Association for the period 1993 to 2007. We find that labor productivity growth is primarily driven by factor intensity and technical change. Efficiency change is declining with increasing productivity growth, and technical change is not Hicks-neutral and occurs at high levels of factor intensity, suggesting that innovation is embodied in factor intensity.
This Summary for Policymakers presents key findings from the Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX). The SREX approaches the topic by assessing the scientific literature on issues that range from the relationship between climate change and extreme weather and climate events (‘climate extremes’) to the implications of these events for society and sustainable development. The assessment concerns the interaction of climatic, environmental, and human factors that can lead to impacts and disasters, options for managing the risks posed by impacts and disasters, and the important role that non-climatic factors play in determining impacts. Box SPM.1 defines concepts central to the SREX.
The character and severity of impacts from climate extremes depend not only on the extremes themselves but also on exposure and vulnerability. In this report, adverse impacts are considered disasters when they produce widespread damage and cause severe alterations in the normal functioning of communities or societies. Climate extremes, exposure, and vulnerability are influenced by a wide range of factors, including anthropogenic climate change, natural climate variability, and socioeconomic development (Figure SPM.1). Disaster risk management and adaptation to climate change focus on reducing exposure and vulnerability and increasing resilience to the potential adverse impacts of climate extremes, even though risks cannot fully be eliminated (Figure SPM.2). Although mitigation of climate change is not the focus of this report, adaptation and mitigation can complement each other and together can significantly reduce the risks of climate change. [SYR AR4, 5.3]
To evaluate the use of routinely collected electronic health data in Medicare claims to identify surgical site infections (SSIs) following hip arthroplasty, knee arthroplasty, and vascular surgery.
Retrospective cohort study.
Four academic hospitals that perform prospective SSI surveillance.
We developed lists of International Classification of Diseases, Ninth Revision, and Current Procedural Terminology diagnosis and procedure codes to identify potential SSIs. We then screened for these codes in Medicare claims submitted by each hospital on patients older than 65 years of age who had undergone 1 of the study procedures during 2007. Each site reviewed medical records of patients identified by either claims codes or traditional infection control surveillance to confirm SSI using Centers for Disease Control and Prevention/ National Healthcare Safety Network criteria. We assessed the performance of both methods against all chart-confirmed SSIs identified by either method.
Claims-based surveillance detected 1.8–4.7-fold more SSIs than traditional surveillance, including detection of all previously identified cases. For hip and vascular surgery, there was a 5-fold and 1.6-fold increase in detection of deep and organ/space infections, respectively, with no increased detection of deep and organ/space infections following knee surgery. Use of claims to trigger chart review led to confirmation of SSI in 1 out of 3 charts for hip arthroplasty, 1 out of 5 charts for knee arthroplasty, and 1 out of 2 charts for vascular surgery.
Claims-based SSI surveillance markedly increased the number of SSIs detected following hip arthroplasty, knee arthroplasty, and vascular surgery. It deserves consideration as a more effective approach to target chart reviews for identifying SSIs.