bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methamphetamine use can mimic testicular torsion
Authors: Doherty Michael H. , Gerscovich Eugenio O. , Corwin Michael T. , Wilkendorf Stephen R. 
Published: April 2013

ABSTRACTWe report the case of a patient presenting with the classic clinical appearance of testicular torsion. Ultrasound showed testicular ischemia supporting the clinical diagnosis, but the lack of visualization of spermatic cord torsion was of concern. An attempt of clinical detorsion was considered unsuccessful and the patient was explored. No torsion was found. On postoperative review of the patient's medical history, we found methamphetamine use, with a positive urine test at the time of his emergent consultation for the scrotal pain episode. The use of amphetamines has been previously reported as the cause of ischemia of multiple organs, but we could not find previous reports of involvement of the testis mimicking torsion. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 41:461–463, 2013
A fatal complication of ultrasound‐guided abdominal paracentesis
Authors: Seidler Matthew , Sayegh Karl , Roy Anne , Mesurolle Benoît 
Published: April 2013

ABSTRACTUltrasound‐guided abdominal paracentesis is a procedure that is frequently performed by radiologists for both diagnostic and therapeutic purposes. This procedure has been shown to be safe with few complications. We report the case of a patient who underwent an ultrasound‐guided therapeutic abdominal paracentesis for refractory ascites complicated by intraperitoneal hemorrhage leading to death. This case suggests that ultrasound‐guided paracentesis may need to become a more standardized procedure and that in the event of hemorrhage, alternative treatment options such as embolization or surgical intervention should be utilized when manual compression fails. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 41:457–460, 2013;
Monitoring of central retinal artery and vein with color doppler ultrasound during heart surgery as an alternative to transcranial doppler ultrasonography: A case report
Authors: Venturini Massimo , Zambon Massimo , Cristel Giulia , Agostini Giulia , Querques Giulia , Colombo Michele , Benussi Stefano , Landoni Giovanni , Zangrillo Alberto , Del Maschio Alessandro 
Published: April 2013

ABSTRACTCardiac surgery can have severe neurologic complications. The noninvasive monitoring of intracranial circulation during heart surgery is usually performed with transcranial Doppler ultrasonography. We present the case of a 66‐year‐old man who underwent elective cardiac surgery for aortic valve replacement and coronary artery bypass graft, in whom monitoring was performed by simultaneously assessing blood flow velocity in the central retinal artery and vein. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:112–115, 2014
Lithosphere structure and thickness beneath the North China Craton from joint inversion of ambient noise and surface wave tomography
Authors: Tang Youcai , Chen Y. John , Zhou Shiyong , Ning Jieyuan , Ding Zhifeng 
Published: April 2013

AbstractWe imaged detailed 3‐D crustal and uppermost mantle seismic structures in the North China Craton from inversion of Rayleigh wave phase velocity at periods of 6 to 143 s. The phase velocities were obtained from a combination of ambient noise and teleseismic surface wave tomography, and then the phase velocities were inverted to S‐wave velocities. The results show that both the Huabei Basin and Ordos Block have markedly rapid variations in both crustal velocities and the Moho depth. Huabei Basin has a thin (31–34 km) crust with low velocities while Ordos Block has a thick (~40 km) crust with high velocities. We also estimated the lithospheric thickness from the inverted S‐wave velocities using a simple S‐wave velocity/temperature relationship. Huabei Basin was imaged as a low S‐wave‐velocity anomaly in the uppermost mantle with very thin lithosphere (~65 km), while Ordos Block was revealed as a high S‐wave‐velocity anomaly with rather thick lithosphere (>120 km). These results indicated that Huabei Basin and Ordos Block have different thermal and/or chemical properties and had experienced different mantle processes and evolution histories since the Cenozoic. Furthermore, slow S‐wave velocities and very thin lithosphere (~65 km) were also found beneath Hetao and Weihe rifts bounding Ordos Block at north and south, respectively. However, Shanxi Rift—the boundary between Huabei Basin and Ordos Block—had a much thicker and higher velocity lithosphere than Hetao and Weihe rifts.
Air‐mass origin as a diagnostic of tropospheric transport
Authors: Orbe Clara , Holzer Mark , Polvani Lorenzo M. , Waugh Darryn 
Published: April 2013

AbstractWe introduce rigorously defined air masses as a diagnostic of tropospheric transport. The fractional contribution from each air mass partitions air at any given point according to either where it was last in the planetary boundary layer or where it was last in contact with the stratosphere. The utility of these air‐mass fractions is demonstrated for the climate of a dynamical core circulation model and its response to specified heating. For an idealized warming typical of end‐of‐century projections, changes in air‐mass fractions are in the order of 10% and reveal the model's climate change in tropospheric transport: poleward‐shifted jets and surface‐intensified eddy kinetic energy lead to more efficient stirring of air out of the midlatitude boundary layer, suggesting that, in the future, there may be increased transport of black carbon and industrial pollutants to the Arctic upper troposphere. Correspondingly, air is less efficiently mixed away from the subtropical boundary layer. The air‐mass fraction that had last stratosphere contact at midlatitudes increases all the way to the surface, in part due to increased isentropic eddy transport across the tropopause. Correspondingly, the air‐mass fraction that had last stratosphere contact at high latitudes is reduced through decreased downwelling across the tropopause. A weakened Hadley circulation leads to decreased interhemispheric transport in the model's future climate.
Boundary layer sources for the Asian anticyclone: Regional contributions to a vertical conduit
Authors: Bergman John W. , Fierli Federico , Jensen Eric J. , Honomichl Shawn , Pan Laura L. 
Published: April 2013

AbstractThe transport of air from the planetary boundary layer (PBL) into the Asian Summer Monsoon anticyclone is investigated using backward trajectories initiated within the anti‐cyclone at 100 mb and 200 mb during August 2011. Transport occurs through a well‐defined conduit centered over the southern Tibetan plateau, where convection lofts air parcels into the anticyclone. The conduit, as a dynamical feature, is distinct from the anticyclone. Thus, while the anticyclone influences transport through the upper troposphere and lower stratosphere, it does not by itself define a transport pipeline through that region. To quantify model sensitivities, parcel trajectories are calculated using wind fields from multiple analysis data sets (European Centre for Medium‐Range Weather Forecasts, National Center for Environmental Prediction's Global Forecasting System, and NASA's Modern‐Era Retrospective Analysis for Research and Applications [MERRA]) and from synthetically modified data sets that explore the roles of vertical motion and horizontal resolution for discrepancies among these calculations. All calculations agree on the relative contributions to PBL sources for the anticyclone from large‐scale regions with Tibetan Plateau and India/SE Asia being the most important. However, they disagree on the total fraction of air within the anticyclone that was recently in the PBL. At 200 mbar, calculations using MERRA are clear outliers due to problematic vertical motion in those data. Large differences among the different data sets at 100 mbar are more closely related to horizontal resolution. It is speculated that this reflects the importance of deep, small‐scale convective updrafts for transport to 100 mbar.
Aerosol climatology at Delhi in the western Indo‐Gangetic Plain: Microphysics, long‐term trends, and source strengths
Authors: Lodhi Neelesh K. , Beegum S. Naseema , Singh Sachchidanand , Kumar Krishan 
Published: April 2013

AbstractWe present the climatology of aerosol microphysics, its trends, and impact of potential sources based on the long term measurements (for a period of 11.5 years from December 2001 to May 2012) of aerosol optical depths (AOD) in the spectral range 340–1020 nm from an urban center Delhi (28.6°N, 77.3°E, 238 m mean sea level) in the western Indo‐Gangetic Plain (IGP). The study is the first ever long‐term characterization of aerosols over the western IGP from the ground‐based measurements. AODs are known to affect the air quality, visibility, radiative balance, and cloud microphysics of the region and IGP is one of the highest populated and polluted regions of the world. Our measurements show consistently high AOD during the entire period of observation. The seasonal variations of spectral AODs and Angstrom parameters are generally consistent every year. The AODs show a weak but statistically significant (in 95% confidence level) decreasing trend approximately −0.02/year at 500 nm, possibly, modulated by the pre‐monsoon heavy dust loading during the first half of the observation period. The climatological monthly mean AOD at shorter wavelengths peaks twice, during June and November, while at longer wavelengths it shows only one peak in June. The annual variations of Angstrom exponent, α and its derivative, α′ suggest the prevalence of multi‐modal aerosol size distributions at Delhi. The coarse‐mode aerosols dominate during summer (March–June) and monsoon (July–September) seasons, whereas fine/accumulation mode enhances during post‐monsoon (October–November) and winter (December–February) seasons. Potential advection pathways have been identified using concentration weighted trajectory (CWT) analysis of the 5 day isentropic air mass back trajectories at the observation site and their seasonal variations are discussed.
Automated retrievals of volcanic ash and dust cloud properties from upwelling infrared measurements
Authors: Pavolonis Michael J , Heidinger Andrew K. , Sieglaff Justin 
Published: April 2013

AbstractA fully automated, globally applicable algorithm to retrieve ash and dust cloud properties from infrared satellite measurements is presented. The algorithm, which will serve as the official operational algorithm of the next generation Geostationary Operational Environmental Satellite (GOES‐R), utilizes an optimal estimation framework that allows uncertainties in the measurements and forward model to be taken into account and uncertainty estimates for each of the retrieved parameters to be determined. The retrieval approach is globally applicable because background atmospheric water vapor, surface temperature, and surface emissivity are explicitly accounted for on a pixel‐by‐pixel basis. The retrieval is demonstrated using the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on‐board the Second Generation Meteosat. Ash clouds from the 2010 eruption of Eyjafjallajökull in Iceland and the 2010 eruption of Soufriere Hills in the eastern Caribbean and a Saharan dust cloud were analyzed, and the accuracy of the retrieval was evaluated using spaceborne lidar measurements. The validation analysis shows that the retrieved ash/dust cloud height, cloud emissivity, and effective particle radius generally agrees well with lidar measurements, especially when volcanic ash clouds are assumed to be composed of andesite and dust clouds composed of kaolinite.
Observations of the atmospheric boundary layer height under marine upstream flow conditions at a coastal site
Authors: Peña A. , Gryning S.‐E. , Hahmann A.N. 
Published: April 2013

AbstractWe investigate several lidar‐type instruments and methodologies for boundary layer height (BLH) estimation during 2 days at a coastal site for winds that experience marine upstream flow conditions. Wavelet and profile fitting procedures on the aerosol backscatter signals from a ceilometer and an aerosol lidar reveal similar BLHs, but their agreement depends on the presence of clouds and the instrument signal, among others. BLHs derived by a threshold on the carrier‐to‐noise profiles of a wind lidar agree well with those derived by using a threshold on the backscatter profile of the ceilometer and are used as reference for a 10 day BLH intercomparison. Furthermore, the BLHs from the aerosol analysis are comparable to those derived from wind speed and direction profiles from combined mast/wind lidar measurements. The BLH derived from simulations performed with the Weather Research and Forecasting (WRF) model shows similar behavior compared to the lidar observations. The seasonal diurnal variation of the BLH for 2010, derived from the wind lidar and ceilometer thresholds, shows similar BLHs but generally higher values compared to that from WRF. No clear BLH diurnal variation is observed neither from the observations nor from the WRF model outputs, except in summer for the latter. Both observations and WRF model simulations reveal higher BLHs during autumn compared to spring time. These BLHs are used to evaluate the intra‐annual variation and show high peaks in September, November, and February.
Stochastic seasonality of rainfall in New Zealand
Authors: Sansom John , Thomson Peter , Carey‐Smith Trevor 
Published: April 2013

AbstractSeasonality is an important source of variation in many processes and needs to be incorporated into rainfall models. The stochastic seasonal rainfall models for high temporal resolution data [Sansom and Thomson, 2010] and daily data (T. Carey‐Smith et al., A hidden seasonal switching model for multisite daily rainfall, manuscript in preparation 2012) both depend on the specification of one day of the year for each season being in the particular season. So, if the seasonality is to be represented by four seasons then it is necessary to provide four dates on each of which it can be said that, every year, the season is of the first, second, third or fourth type respectively on that day of the year. The model fitting can only proceed once these dates, the mid‐seasons, have been provided.In a region of large seasonal rainfall variation the determination of these mid‐seasons would not be difficult and the model fitting not sensitive to their choice. However, although it is clearly evident in the annual pattern of monthly accumulations, New Zealand's rainfall seasonality is not strong and careful assessment of the mid‐season dates is necessary. They need to be estimated with a precision of days and the 55‐year long rainfall records of daily data from 141 stations spread across New Zealand were analysed on a regional basis. The analysis found regionally coherent dates when the mean daily rain rate changed significantly and that over the years these dates could be modelled as a four component von Mises distribution with characteristics consistent with stochastic seasonality.
Retrieval and validation of global, direct, and diffuse irradiance derived from SEVIRI satellite observations
Authors: Greuell W. , Meirink J. F. , Wang P. 
Published: April 2013

AbstractThis paper discusses Surface Insolation under Clear and Cloudy skies derived from SEVIRI imagery (SICCS), a physics‐based, empirically adjusted algorithm developed for estimation of surface solar irradiance from satellite data. Its most important input are a cloud mask product and cloud properties derived from Meteosat/Spinning Enhanced Visible and Infrared Imager (SEVIRI) observations. These observations set the characteristics of the output, namely, a temporal resolution of 15 min, a nadir spatial resolution of 3 × 3 km2, the period from January 2004 until at least November 2012, and the domain equal to most of the Meteosat disc. SICCS computes global, direct, and diffuse irradiance separately. Direct irradiance for cloudy skies is estimated with an empirical method. Hourly means retrieved with SICCS were validated with data from eight Baseline Surface Radiation Network stations for the year 2006. We found median values of the station biases of +6 W/m2 (+5%) for direct irradiance, +1 W/m2 (+1%) for diffuse irradiance, and +7 W/m2 (+2%) for global irradiance. Replacing the three‐hourly aerosol optical thickness input by monthly means introduces considerable additional biases in the clear‐sky direct (−6%) and diffuse (+26%) irradiances. The performance of SICCS does not degrade when snow covers the surface. Biases do not vary with cloud optical thickness and cloud particle radius. However, the bias in global transmissivity tends to decrease with increasing cloud heterogeneity, and the bias in direct transmissivity is a function of the solar zenith angle. We discuss why satellite retrieval of surface solar irradiance is relatively successful.
Microphysical simulations of large volcanic eruptions: Pinatubo and Toba
Authors: English Jason M. , Toon Owen B. , Mills Michael J. 
Published: April 2013

AbstractSimulations of stratospheric clouds from eruptions ranging in size from the 1991 eruption of Mount Pinatubo to that of Toba 74,000 years ago have been completed using a 3D microphysical sectional aerosol model advectively coupled to a general circulation model with prognostic chemistry (Whole Atmosphere Community Climate Model/Community Aerosol and Radiation Model for Atmospheres). For Pinatubo, properties of the aerosol cloud peak within the ranges derived from observations in the Northern Hemisphere, but reduce faster than observed, and a general low bias is found in the Southern Hemisphere. These biases could be reduced by adding aerosol radiative coupling, a quasi‐biennial oscillation, and the Cerro Hudson eruption to the model. Simulations of eruptions 10 times and 100 times larger than Pinatubo suggest burdens and Aerosol Optical Depth increase less than linearly (a 100‐fold injection increase produces a 20‐fold AOD increase) due to particle growth and sedimentation, consistent with previous work that also found the radiative forcings from large eruptions to be self‐limiting. Global‐averaged AOD remains elevated for 1, 2, and 4 years, respectively, for the three simulated eruptions. The inclusion of van der Waals forces in our coagulation scheme increases peak effective radius and reduces peak AOD by about 10–20%, with bigger effects for larger eruptions. Our simulations find peak mode size to vary by up to an order of magnitude and mode width to vary by up to 50%, suggesting that two‐moment modal models may not accurately capture the evolving size distribution. These simulations suggest the value of including van der Waals forces in the coagulation scheme and sectional size distributions in climate models.
Impact of dataset choice on calculations of the short‐term cloud feedback
Authors: Dessler A. E. , Loeb N.G. 
Published: April 2013

AbstractDessler [2010, hereafter D10] estimated the magnitude of the cloud feedback in response to short‐term climate variations and concluded that it was likely positive, with an average magnitude of +0.50 ± 0.75 W/m2/K. This paper investigates the sensitivity of D10's results to the choice of clear‐sky top‐of‐atmosphere flux (ΔRclear‐sky), surface temperature (ΔTs), and reanalysis data sets. Most of the alternative ΔRclear‐sky data sets produce cloud feedbacks that are close to D10, differing by 0.2–0.3 W/m2/K. An exception is the Terra SSF1deg ΔRclear‐sky product, which produces an overall negative cloud feedback. However, a critical examination of those data leads us to conclude that that result is due to problems in the Terra ΔRclear‐sky arising from issues with cloud clearing prior to July 2001. Eliminating the problematic early portion yields a cloud feedback in good agreement with D10. We also present an alternative calculation of the cloud feedback that does not require an estimate of ΔRclear‐sky, and this calculation also produces a positive cloud feedback in agreement with D10. The various ΔTs data sets produce cloud feedbacks that differ by as much as 0.8 W/m2/K. The choice of reanalysis, used as a source of ΔRclear‐sky or as adjustments for the cloud radiative forcing, has a small impact on the inferred cloud feedback. Overall, these results confirm the robustness of D10's estimate of a likely positive feedback.
Meteorology and dust in the central Sahara: Observations from Fennec supersite‐1 during the June 2011 Intensive Observation Period
Authors: Marsham J. H. , Hobby M. , Allen C. J. T. , Banks J. R. , Bart M. , Brooks B. J. , Cavazos‐Guerra C. , Engelstaedter S. , Gascoyne M. , Lima A. R. , Martins J. V. , McQuaid J. B. , O'Leary A. , Ouchene B. , Ouladichir A. , Parker D. J. , Saci A. , Salah‐Ferroudj M. , Todd M. C. , Washington R. 
Published: April 2013

AbstractWe describe observations from the Fennec supersite at Bordj Badji Mokhtar (BBM) made during the June 2011 Fennec Intensive Observation Period. These are the first detailed in situ observations of meteorology and dust from the central Sahara, close to the center of the Saharan heat low and the summertime dust maximum. Historically, a shortage of such Saharan observations has created problems for evaluating processes, models, and remote sensing. There was a monsoon influence at BBM before 8 June and after 12 June, with dry Harmattan winds in between. A split boundary layer, generated by ventilation from the Atlantic, persisted during the drier phase. Extensive cold pools (haboobs) and microburst‐type events were regularly observed. Moisture reached BBM at night from the monsoon and the embedded haboobs. As well as the regularly occurring nocturnal low‐level jet (LLJ), a Saharan upper boundary layer (650 hPa) jet was observed, where winds feel drag from dry convection in the afternoon. This jet is linked to the diurnal cycles of moisture and cloud. Most dust was observed in the cloudier monsoon‐affected periods, and covarying dust and cloud amounts explain most of the variations in shortwave radiation that control the surface sensible flux. Dustiness is related to a standard parameterization of uplift using 10 m winds (“uplift potential”), and this is used to estimate uplift. Around 50% of uplift is nocturnal. Around 30% is from the LLJ, and 50% is from haboobs, which are mainly nocturnal. This demonstrates, for the first time from observations, the key role of haboobs, which are problematic for models.
Classification of convective/stratiform echoes in radar reflectivity observations using a fuzzy logic algorithm
Authors: Yang Yi , Chen Xin , Qi Youcun 
Published: April 2013

AbstractIn radar reflectivity observations, the convective and stratiform rain types always have poorly defined boundaries, which caused problem for rain classification. A fuzzy logic (FL) algorithm is developed to classify convective and stratiform rainfall based on the radar reflectivity observations in the next three steps: First, the algorithm is calibrated on Hefei Doppler radar site in China. Four features are selected based on a dataset for calibration, which spanned the period from 29 June to 23 July 2003; and the features basically represent a subjective choice of characteristics that are expected to distinguish different rain types. In the second step, membership functions are used to determine the degree to which each feature belongs to each rain type in the fuzzification process. Finally, the degree of fuzzification for each input feature is multiplied by predetermined weighting coefficients. The weighted degrees of the fuzzification are aggregated to produce a single value for each rain type. The aggregation can represent the possibility of classified rainfall type, and larger value reveals the higher potential for a particular class. The FL algorithm has been applied to four typical independent individual cases collected by Hefei Doppler radar, which have not been included in the database for calibration. Results show that the classification using the proposed FL algorithm is physically reasonable according to the analysis of three‐dimensional radar reflectivity patterns, implying that the proposed FL algorithm has a great potential for the precipitation classification.