Spectrum of injuries resulting from gunshot wounds in car hijacking: a South African experience.

BACKGROUND: Car hijacking, known as “carjacking”, is a form of aggravated robbery of a vehicle from the driver frequently involving firearm and is common in South Africa. There is, however, little literature on the spectrum of injuries sustained by victims of car hijacking. The study aimed to describe the spectrum of gunshot wound-related (GSW) injuries and review our experience of management of victims of car hijacking in our trauma center based in South Africa. METHODS: A retrospective review was conducted during an 8-year period from January 2010 to January 2018 on all patients who presented with any form of GSW after a car hijacking incident. RESULTS: During the 8-year study period, a total of 101 patients were identified. Seventy-four percent were male (75 of 101) and the mean age was 34 years. The mean time from injury to arrival at our trauma center was 7 hours (rural district: 10 hours, urban district: 4 hours; p<0.001). Seventy-five percent (76 of 101) of all patients sustained GSWs to multiple body regions, whereas the remaining 25% (25 of 101) were confined to a single body region. The most common region involved was the chest (48 cases), followed by the abdomen (46 cases) and neck (34 cases). Sixty-three of the 101 (62%) patients required one or more operative interventions. The most common procedure was laparotomy (28 cases), followed by vascular (20 cases) and neck (14) exploration. Eighteen percent (18 of 101) of all patients required intensive care unit admission. The mean length of hospital stay was 7 days. The overall morbidity was 13% (16 of 101) and the overall mortality was 18% (18 of 101). DISCUSSION: The spectrum of injuries from GSW related to car hijacking commonly involves close range GSWs to multiple body regions. Torso trauma is common and a substantial proportion of victims require major operative interventions. The mortality from these injuries is significant. LEVELS OF EVIDENCE: Level III

Synthesis of satellite (MODIS), aircraft (ICARTT), and surface (IMPROVE, EPA-AQS, AERONET) aerosol observations over eastern North America to improve MODIS aerosol retrievals and constrain surface aerosol concentrations and sources

We use an ensemble of satellite (MODIS), aircraft, and ground-based aerosol observations during the ICARTT field campaign over eastern North America in summer 2004 to (1) examine the consistency between different aerosol measurements, (2) evaluate a new retrieval of aerosol optical depths (AODs) and inferred surface aerosol concentrations (PM2.5) from the MODIS satellite instrument, and (3) apply this collective information to improve our understanding of aerosol sources. The GEOS-Chem global chemical transport model (CTM) provides a transfer platform between the different data sets, allowing us to evaluate the consistency between different aerosol parameters observed at different times and locations. We use an improved MODIS AOD retrieval based on locally derived visible surface reflectances and aerosol properties calculated from GEOS-Chem. Use of GEOS-Chem aerosol optical properties in the MODIS retrieval not only results in an improved AOD product but also allows quantitative evaluation of model aerosol mass from the comparison of simulated and observed AODs. The aircraft measurements show narrower aerosol size distributions than those usually assumed in models, and this has important implications for AOD retrievals. Our MODIS AOD retrieval compares well to the ground-based AERONET data (R = 0.84, slope = 1.02), significantly improving on the MODIS c005 operational product. Inference of surface PM2.5 from our MODIS AOD retrieval shows good correlation to the EPA-AQS data (R = 0.78) but a high regression slope (slope = 1.48). The high slope is seen in all AOD-inferred PM2.5 concentrations (AERONET: slope = 2.04; MODIS c005: slope = 1.51) and could reflect a clear-sky bias in the AOD observations. The ensemble of MODIS, aircraft, and surface data are consistent in pointing to a model overestimate of sulfate in the mid-Atlantic and an underestimate of organic and dust aerosol in the southeastern United States. The sulfate overestimate could reflect an excessive contribution from aqueous-phase production in clouds, while the organic carbon underestimate could possibly be resolved by a new secondary pathway involving dicarbonyls

A Class of Eccentric Binaries with Dynamic Tidal Distortions Discovered with Kepler

We have discovered a class of eccentric binary systems within the Kepler data archive that have dynamic tidal distortions and tidally-induced pulsations. Each has a uniquely shaped light curve that is characterized by periodic brightening or variability at time scales of 4-20 days, frequently accompanied by shorter period oscillations. We can explain the dominant features of the entire class with orbitally-varying tidal forces that occur in close, eccentric binary systems. The large variety of light curve shapes arises from viewing systems at different angles. This hypothesis is supported by spectroscopic radial velocity measurements for five systems, each showing evidence of being in an eccentric binary system. Prior to the discovery of these 17 new systems, only four stars, where KOI-54 is the best example, were known to have evidence of these dynamic tides and tidally-induced oscillations. We perform preliminary fits to the light curves and radial velocity data, present the overall properties of this class and discuss the work required to accurately model these systems.Comment: 13 pages, submitted to Ap

Measuring Transit Signal Recovery in the Kepler Pipeline II: Detection Efficiency as Calculated in One Year of Data

The Kepler planet sample can only be used to reconstruct the underlying planet occurrence rate if the detection efficiency of the Kepler pipeline is known, here we present the results of a second experiment aimed at characterising this detection efficiency. We inject simulated transiting planet signals into the pixel data of ~10,000 targets, spanning one year of observations, and process the pixels as normal. We compare the set of detections made by the pipeline with the expectation from the set of simulated planets, and construct a sensitivity curve of signal recovery as a function of the signal-to-noise of the simulated transit signal train. The sensitivity curve does not meet the hypothetical maximum detection efficiency, however it is not as pessimistic as some of the published estimates of the detection efficiency. For the FGK stars in our sample, the sensitivity curve is well fit by a gamma function with the coefficients a = 4.35 and b = 1.05. We also find that the pipeline algorithms recover the depths and periods of the injected signals with very high fidelity, especially for periods longer than 10 days. We perform a simplified occurrence rate calculation using the measured detection efficiency compared to previous assumptions of the detection efficiency found in the literature to demonstrate the systematic error introduced into the resulting occurrence rates. The discrepancies in the calculated occurrence rates may go some way towards reconciling some of the inconsistencies found in the literature.Comment: 13 pages, 7 figures, 1 electronic table, accepted by Ap

The impact of local sources and long-range transport on aerosol properties over the northeast U.S. region during INTEX-NA

We use data collected aboard the NASA DC-8 aircraft during the summer 2004, Intercontinental Transport and Chemical Evolution Experiment over North America (INTEX-NA) field campaign to examine the origin, composition, physical and optical properties of aerosols within air masses sampled over and downwind of the northeastern U.S. We note that aerosol concentrations within the region exhibited steep vertical gradients and significant variability in both time and space. An examination of air mass chemical signatures and backward trajectories indicates that transport from four, significantly different source regions contributed to the variability: the subtropical Atlantic Ocean (AO); the U.S. west coast and eastern Pacific (WCP); the U.S. east coast and Midwestern states (EC); and northwest Canada and Alaska (CA). AO air masses were typically confined to below 2 km altitude, exhibited low pollutant contents, contained enhanced levels of sea salt, and were typically observed when the Bermuda High strengthened. The most common air mass present in the upper troposphere, WCP air often contained weak dust and aged pollution enhances from convective input occurring over the central part of the continent. CA air exhibited enhancements in anthropogenic pollution tracers below 2 km and contained some black-carbon rich haze layers between 3 and 5 km that could be traced to forest fires burning in western Canada and Alaska. EC air was prevalent at lower elevations throughout the study area and exhibited enhanced scattering along with elevated levels of sulfate aerosols and combustion tracers. There is an overall balance between the observed cations and anions for all cases, except EC air mass below 4 km

Gourds and squashes (Cucurbita spp.) adapted to megafaunal extinction and ecological anachronism through domestication.

The genus Cucurbita (squashes, pumpkins, gourds) contains numerous domesticated lineages with ancient New World origins. It was broadly distributed in the past but has declined to the point that several of the crops' progenitor species are scarce or unknown in the wild. We hypothesize that Holocene ecological shifts and megafaunal extinctions severely impacted wild Cucurbita, whereas their domestic counterparts adapted to changing conditions via symbiosis with human cultivators. First, we used high-throughput sequencing to analyze complete plastid genomes of 91 total Cucurbita samples, comprising ancient (n = 19), modern wild (n = 30), and modern domestic (n = 42) taxa. This analysis demonstrates independent domestication in eastern North America, evidence of a previously unknown pathway to domestication in northeastern Mexico, and broad archaeological distributions of taxa currently unknown in the wild. Further, sequence similarity between distant wild populations suggests recent fragmentation. Collectively, these results point to wild-type declines coinciding with widespread domestication. Second, we hypothesize that the disappearance of large herbivores struck a critical ecological blow against wild Cucurbita, and we take initial steps to consider this hypothesis through cross-mammal analyses of bitter taste receptor gene repertoires. Directly, megafauna consumed Cucurbita fruits and dispersed their seeds; wild Cucurbita were likely left without mutualistic dispersal partners in the Holocene because they are unpalatable to smaller surviving mammals with more bitter taste receptor genes. Indirectly, megafauna maintained mosaic-like landscapes ideal for Cucurbita, and vegetative changes following the megafaunal extinctions likely crowded out their disturbed-ground niche. Thus, anthropogenic landscapes provided favorable growth habitats and willing dispersal partners in the wake of ecological upheaval.Research was supported by The Pennsylvania State University Huck Institutes of the Life Sciences and College of the Liberal Arts (G.H.P.), Wenner–Gren post-PhD Research Grant 8770 and Natural Environment Research Council Independent Research Fellowship NE/L012030/1 (to L.K.), and the Smithsonian Institution (B.D.S.). Instrumentation was funded by the National Science Foundation through Grant OCI–0821527.This is the author accepted manuscript. The final version is available from PNAS via http://dx.doi.org/10.1073/pnas.151610911

Photometric Analysis in the Kepler Science Operations Center Pipeline

We describe the Photometric Analysis (PA) software component and its context in the Kepler Science Operations Center (SOC) pipeline. The primary tasks of this module are to compute the photometric flux and photocenters (centroids) for over 160,000 long cadence (~thirty minute) and 512 short cadence (~one minute) stellar targets from the calibrated pixels in their respective apertures. We discuss the science algorithms for long and short cadence PA: cosmic ray cleaning; background estimation and removal; aperture photometry; and flux-weighted centroiding. We discuss the end-to-end propagation of uncertainties for the science algorithms. Finally, we present examples of photometric apertures, raw flux light curves, and centroid time series from Kepler flight data. PA light curves, centroid time series, and barycentric timestamp corrections are exported to the Multi-mission Archive at Space Telescope [Science Institute] (MAST) and are made available to the general public in accordance with the NASA/Kepler data release policy

Defining the need for surgical intervention following a snakebite still relies heavily on clinical assessment: The experience in Pietermaritzburg, South Africa

Background. This audit of snakebites was undertaken to document our experience with snakebite in the western part of KwaZulu-Natal (KZN) Province, South Africa (SA).Objective. To document our experience with snakebite in the western part of KZN, and to interrogate the data on patients who required some form of surgical intervention.Methods. A retrospective study was undertaken at the Pietermaritzburg Metropolitan Trauma Service, Pietermaritzburg, SA. The Hybrid Electronic Medical Registry was reviewed for the 5-year period January 2012 - December 2016. All patients admitted to the service for management of snakebite were included.Results. The offending snake is rarely identified, and the syndromic approach is now the mainstay of management. Most envenomations seen during the study period were cytotoxic, presenting with painful progressive swelling (PPS). We did not see any purely neurotoxic or haemotoxic envenomations. Antivenom is required for a subset of patients. The indications are essentially PPS that increases by &gt;15 cm over an hour, PPS up to the elbow or knee after 4 hours, PPS of the whole limb after 8 hours, threatened airway, shortness of breath, associated clotting abnormalities and compartment syndrome. If no symptoms have manifested within 1 hour of a snakebite, clinically significant envenomation is unlikely to have occurred. Antivenom is associated with a high rate of anaphylaxis and should only be administered when absolutely indicated, preferably in a high-care setting under continuous monitoring. The need for surgery is less well defined. Urgent surgery is indicated for compartment syndrome of the limb, which is a potentially life- and limb-threatening condition. Its diagnosis is usually made clinically, but this is difficult in snakebites. Morbidity and cost increase dramatically once fasciotomy is required, as evidenced by much longer hospital stay. There is frequently a degree of cross-over between cytotoxicity and haemotoxicity in envenomations that require fasciotomy, which means that fasciotomy may result in catastrophic bleeding and should be preceded by the administration of antivenom, especially in patients with a low platelet count or a high international normalised ratio. Physiological and biochemical markers are unhelpful in assessing the need for fasciotomy. Objective methods include measurement of compartment pressures and ultrasound.Conclusion. The syndromic management of snakebite is effective and safe. There is a high incidence of anaphylactic reactions to antivenom, and its administration must be closely supervised. In our area we overwhelmingly see cytotoxic snakebites with PPS. Surgery is often needed, and we need to refine our algorithms in terms of deciding on surgery