bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cesarean Scar Pregnancies
Authors: Timor-Tritsch Ilan E. , Khatib Nizar , Monteagudo Ana , Ramos Joanne , Berg Robert , Kovács Sándor 
Published: March 2015

ObjectivesTo evaluate the management, clinical courses, and outcomes of cesarean scar pregnancies diagnosed in the first trimester.MethodsWe identified 60 cases of cesarean scar pregnancies diagnosed between 5 and 14 weeks. Group A contained 48 patients with fetal/embryonic cardiac activity; group B comprised 12 patients without cardiac activity; and group C included 11 patients with cardiac activity who chose expectant management.ResultsFive of the 48 patients (10.4%) in group A were successfully treated for vaginal bleeding. Thirty‐three (68.7%) received methotrexate injections, and all had full resolution. Three (6.3%) required uterine artery embolization for late‐developing arteriovenous malformations. Ten of the 12 patients (83.3%) in group B were managed expectantly and had full recovery. Two of the 10 (20.0%) had arteriovenous malformations; 1 had unsuccessful uterine artery embolization followed by a hysterectomy, and the second requested a hysterectomy. Ten of the 11 patients (90.9%) in group C continued the pregnancies. One declined local injection. Four of the 10 (40.0%) delivered live offspring by successive elective cesarean deliveries. Three (30.0%) had hysterectomies for placenta percreta, and 1 did not have a hysterectomy after delivery. Five (50%) had second‐trimester complications, all leading to hysterectomies. Of the 60 patients, 20 (33.3%) had serious complications: 5 had arteriovenous malformations; 4 had uterine artery embolization; and 11 had hysterectomies.ConclusionsA cesarean scar pregnancy is a serious complication for patients who have had cesarean deliveries. Counseling, treatment, and follow‐up are challenging for patients and caregivers. However, emerging data from different management approaches confirm that a cesarean scar pregnancy may progress and result in a live neonate at the expense of further fertility. This study confirmed that expectant management of a cesarean scar pregnancy is associated with a high risk of hysterectomy due to morbidly adherent placenta.
Biopsy Versus Conservative Management of Sonographically Benign‐Appearing Solid Breast Masses in Adolescents
Authors: Jawahar Anugayathri , Vade Aruna , Ward Kathleen , Okur Gokcan , Subbaiah Perla 
Published: March 2015

ObjectivesTo determine whether the size of palpable solid breast masses in adolescents at initial sonography and their growth at follow‐up sonography could be used to decide between conservative management and tissue biopsy.MethodsThis retrospective study included 37 adolescent female patients with 45 palpable benign‐appearing solid breast masses on initial sonography. They were grouped as follows: group I, masses undergoing follow‐up sonography with subsequent biopsy (n = 9); group II, masses undergoing biopsy without follow‐up sonography (n = 13); and group III, masses undergoing follow‐up sonography without biopsy (n = 23). The largest dimension, volume, volume change per month, and change in the sonographic appearance were analyzed to predict the need for biopsy. A combination of a largest dimension greater than 3 cm and volume change per month greater than 16% was used to assess the need for biopsy. Sonograms of 22 masses were correlated with histopathologic diagnoses.ResultsNone of the masses that underwent follow‐up sonography showed changes in their sonographic appearance. All masses that underwent biopsy were benign on histopathologic analysis. There was no significant difference in the largest dimension among the groups at initial sonography or between groups I and III at follow‐up sonography. The volume change was smaller for fibroadenomas (n = 7; mean, 22.67%) than benign phyllodes tumors (n = 2; mean, 45.30%) in group I, but the difference was not significant (P = .384). However, the volume change for groups I and III showed a significant difference (P = .026). Neither size greater than 3 cm nor volume change greater than 16% predicted pathologic outcomes.ConclusionsIf the combined criteria for assessing benignity of palpable breast masses had been used, biopsy could have been reduced by 89% in group I and deemed not necessary in 96% of group III breast masses.
Utility of Semiquantitative Strain Elastography for Differentiation Between Benign and Malignant Solid Renal Masses
Authors: Onur Mehmet Ruhi , Poyraz Ahmet Kursad , Bozgeyik Zulkif , Onur Ahmet Rahmi , Orhan Irfan 
Published: March 2015

ObjectivesThe aim of this study was to determine the role of semiquantitative strain elastography for differentiation of benign and malignant solid renal masses.MethodsSeventy‐one patients with solid renal masses were prospectively examined with ultrasound elastography after grayscale sonography. Strain elastography was used to compare the stiffness of the renal masses and renal parenchyma. The ratio of strain in a renal mass and nearby renal parenchyma was defined as the strain index value. Mean strain index values for benign masses (n = 29; 24 angiomyolipomas and 5 oncocytomas) and malignant masses (n = 42; 34 renal cell carcinomas, 4 transitional cell carcinomas, 3 metastases, and 1 lymphoma) and mean strain index values for angiomyolipomas and renal cell carcinomas were compared.ResultsThere were no significant differences in the mean age of the patients, mean diameter of the masses, and mean probe‐mass distance between benign and malignant groups. The mean strain index value ± SD for malignant masses (4.05 ± 2.17) was significantly higher than the value for benign masses (1.43 ± 0.94; P < .05). The mean strain index value for renal cell carcinomas (4.30 ± 2.27) was significantly higher than the value for angiomyolipomas (1.28 ± 1.01; P < .0001).ConclusionsStrain elastography may be a useful imaging technique for differentiation between benign and malignant solid renal masses.
Relationship Between the Estimated Glomerular Filtration Rate and Kidney Shear Wave Speed Values Assessed by Acoustic Radiation Force Impulse Elastography
Authors: Bob Flaviu , Bota Simona , Sporea Ioan , Sirli Roxana , Popescu Alina , Schiller Adalbert 
Published: March 2015

ObjectivesThe aim of the study was to establish the relationship between the estimated glomerular filtration rate (GFR) and kidney shear wave speed values assessed by acoustic radiation force impulse (ARFI) elastography.MethodsOur study included 104 patients with or without chronic kidney disease in which the kidney shear wave speed was evaluated by ARFI elastography and correlated with the estimated GFR. Five ARFI measurements were performed in the parenchyma of each kidney. A median value expressed as meters per second was calculated.ResultsFive valid ARFI elastographic measurements were obtained in the right kidney in all patients and in the left kidney in 97.1% of patients. The mean kidney shear wave speed values ± SD in the right and left kidneys were similar: 2.17 ± 0.81 versus 2.06 ± 0.75 m/s (P = .30). The mean kidney shear wave speed decreased with the decrease in the estimated GFR. Statistically significant differences were obtained only when kidney shear wave speed values obtained in patients with an estimated GFR of greater than 90 mL/min/1.73 m2 were compared to values in patients with stage 4 (estimated GFR, 15–29 mL/min/1.73 m2) and stage 5 (estimated GFR, <15 mL/min/1.73 m2) chronic kidney disease: 2.32 ± 0.83 versus 1.62 ± 0.75 m/s (P = .03) and 2.32 ± 0.83 versus 1.66 ± 0.72 m/s (P = .04), respectively. For a cutoff value of 2.26 m/s or lower, kidney shear wave speed had 86.7% sensitivity, 48.3% specificity, a 22.1% positive predictive value, and a 95.6% negative predictive value (area under the receiver operating characteristic curve, 0.692; P = .008) for predicting the presence of an estimated GFR of less than 30 mL/min/1.73 m2.ConclusionsKidney shear wave speed values obtained by ARFI elastography decrease with the decrease in the estimated GFR.
Validation of Color Doppler Sonography for Evaluating Relative Displacement Between the Flexor Tendon and Subsynovial Connective Tissue
Authors: Tat Jimmy , Kociolek Aaron M. , Keir Peter J. 
Published: March 2015

ObjectivesA common pathologic finding in carpal tunnel syndrome is fibrosis and thickening of the subsynovial connective tissue. This finding suggests an etiology of excessive shear forces, with relative longitudinal displacement between the flexor tendon and adjacent subsynovial connective tissue. The purpose of this study was to validate color Doppler sonography for measurement of tendon displacement over time.MethodsEight unmatched fresh frozen cadaver arms were used to evaluate color Doppler sonography for measurement of tendon displacement. The middle flexor digitorum superficialis tendon was moved through a physiologic excursion of 20 mm at 3 different tendon velocities (50, 100, and 150 mm/s).ResultsWe found that color Doppler sonography provided accurate measurement of tendon displacement, with absolute errors of −0.05 mm (50 mm/s), −1.24 mm (100 mm/s), and −2.36 mm (150 mm/s) on average throughout the tendon excursion range. Evaluating relative displacement between the tendon and subsynovial connective tissue during finger flexion‐extension movements also offered insight into the gliding mechanism of the subsynovial connective tissue. During flexion, we observed a curvilinear increase in relative displacement, with greater differential motion at the end range of displacement, likely due to the sequential stretch of the fibrils between successive layers of the subsynovial connective tissue. In extension, there was a linear return in relative displacement, suggesting a different unloading mechanism characterized by uniform relaxation of fibrils.ConclusionsWe demonstrated the validity of color Doppler displacement for use in the evaluation of relative motion. Color Doppler sonography is useful in our understanding of the behavior of the subsynovial connective tissue during tendon excursion, which may elucidate the role of finger motion in the etiology of shear injury.
Sonographic Appearance of Thyroid Cancer in Patients With Hashimoto Thyroiditis
Authors: Durfee Sara M. , Benson Carol B. , Arthaud Dylan M. , Alexander Erik K. , Frates Mary C. 
Published: March 2015

ObjectivesTo determine whether the sonographic appearance of thyroid cancer differs in patients with and without Hashimoto thyroiditis.MethodsPatients with histologically proven thyroid cancer who had thyroid peroxidase (TPO) antibodies measured and sonography performed preoperatively were included. We evaluated each nodule for size, echogenicity, composition, margins, halo, and vascularity and evaluated the background heterogeneity of the gland.ResultsThere were 162 thyroid cancers in 145 patients. Forty‐two patients (29.0%) had Hashimoto thyroiditis with positive TPO antibodies, and 103 patients (71.0%) had negative TPO antibodies. The background echogenicity was more often heterogeneous in TPO antibody–positive patients compared to those who had negative TPO antibodies (57.1% versus 26.2%; P= .0005). Comparing cancers in TPO antibody–positive to TPO antibody–negative patients, there was no significant difference in the size, echogenicity, composition, margins, halo presence, calcification presence and type, or vascularity of the cancerous nodule (P > .05). Among TPO antibody–positive patients, comparing thyroid cancerous nodules in patients with heterogeneous glands to those with homogeneous glands, there was no significant difference in any sonographic characteristic except the margin of the nodule, which was more often irregular or poorly defined in heterogeneous glands and more often smooth in homogeneous glands (P< .05).ConclusionsSonographic features of thyroid cancer are similar in patients with and without Hashimoto thyroiditis. Among patients with Hashimoto thyroiditis and thyroid cancer, the sonographic appearance of the cancerous nodule is similar, except that cancerous nodule margins are more likely to be irregular or poorly defined when the gland is heterogeneous.
Pharmacogenomics of lamotrigine: a possible link to serious cutaneous adverse reactions
Authors: Campbell Rebecca , Beall Jennifer 
Published: March 2015

Abstract

Introduction
Lamotrigine's packaging contains a boxed warning for serious skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis. The purpose of this review is to summarize literature pertaining to HLA genetic polymorphisms that may increase susceptibility to serious skin reactions induced by lamotrigine.

Methods
A literature search of PubMed/MEDLINE and Ovid IPA was conducted using the following search terms: lamotrigine, genetic polymorphism, pharmacogenetics, pharmacogenomics, predictive genetic testing, anticonvulsants, hypersensitivity, and HLA-B.

Results
Three case-control studies were identified focusing on genetic polymorphisms that can cause direct susceptibility to serious skin reactions, such as HLA-B*1502. Other factors were also taken into consideration, such as age, concomitant medications, ethnicity, and smoking status. Most results were not statistically significant but rather hypothesis generating and were limited by small sample size and study design.

Discussion
Further studies are needed to better determine a relationship between genetic polymorphisms and lamotrigine-induced serious skin reactions. However, clinicians should exercise caution when prescribing lamotrigine to patients in whom relevant genetic polymorphisms, such as HLA-B*1502, may be present, such as those of Southeast Asian descent.
Resolution analysis of tomographic slug test head data: Two‐dimensional radial case
Authors: Paradis Daniel , Gloaguen Erwan , Lefebvre René , Giroux Bernard 
Published: March 2015

AbstractHydraulic tomography inverse problems, which are solved to estimate aquifer hydraulic properties between wells, are known to be ill‐conditioned and a priori information is often added to regularize numerical inversion of head data. Because both head data and a priori information have effects on the inversed solution, assessing the meaningful information contained in head data alone is required to ensure comprehensive interpretation of inverse solutions, whether they are regularized or not. This study thus aims to assess the amount of information contained in tomographic slug tests head data to resolve heterogeneity in Kh, Kv/Kh, and Ss. Therefore, a resolution analysis based on truncated singular value decomposition of the sensitivity matrix with a noise level representative of field measurements is applied using synthetic data reflecting a known littoral aquifer. As an approximation of the hydraulic behavior of a real aquifer system, synthetic tomographic experiments and associated sensitivity matrices are generated using a radial flow model accounting for wellbore storage to simulate slug tests in a plane encompassing a stressed well and an observation well. Although fine‐scale resolution of heterogeneities is limited by the diffusive nature of the groundwater flow equations, inversion of tomographic slug tests head data holds the potential to uniquely resolve coarse‐scale heterogeneity in Kh, Kv/Kh, and Ss, as inscribed in the resolution matrix. This implies that tomographic head data can provide key information on aquifer heterogeneity and anisotropy, but that fine‐scale information must be supplied by a priori information to obtain finer details.
Whales and waves: Humpback whale foraging response and the shoaling of internal waves at Stellwagen Bank
Authors: Pineda Jesús , Starczak Victoria , da Silva José C. B. , Helfrich Karl , Thompson Michael , Wiley David 
Published: March 2015

AbstractWe tested the hypothesis that humpback whales aggregate at the southern flank of Stellwagen Bank (SB) in response to internal waves (IWs) generated semidiurnally at Race Point (RP) channel because of the presence of their preferred prey, planktivorous fish, which in turn respond to zooplankton concentrated by the predictable IWs. Analysis of synthetic aperture radar (SAR) images indicates that RP IWs approach the southern flank of SB frequently (∼62% of the images). Published reports of whale sighting data and archived SAR images point to a coarse spatial coincidence between whales and Race Point IWs at SB's southern flank. The responses of whales to IWs were evaluated via sightings and behavior of humpback whales, and IWs were observed in situ by acoustic backscatter and temperature measurements. Modeling of IWs complemented the observations, and results indicate a change of ∼0.4 m/s in current velocity, and ∼1.5 Pa in dynamic pressure near the bottom, which may be sufficient for bottom fish to detect the IWs. However, fish were rare in our acoustic observations, and fish response to the IWs could not be evaluated. RP IWs do not represent the leading edge of the internal tide, and they may have less mass‐transport potential than typical coastal IWs. There was large interannual variability in whale sightings at SB's southern flank, with decreases in both numbers of sightings and proportion of sightings where feeding was observed from 2008 to 2013. Coincidence of whales and IWs was inconsistent, and results do not support the hypothesis.
Isoprene emissions and impacts over an ecological transition region in the U.S. Upper Midwest inferred from tall tower measurements
Authors: Hu Lu , Millet Dylan B. , Baasandorj Munkhbayar , Griffis Timothy J. , Turner Peter , Helmig Detlev , Curtis Abigale J. , Hueber Jacques 
Published: March 2015

AbstractWe present 1 year of in situ proton transfer reaction mass spectrometer (PTR‐MS) measurements of isoprene and its oxidation products methyl vinyl ketone (MVK) and methacrolein (MACR) from a 244 m tall tower in the U.S. Upper Midwest, located at an ecological transition between isoprene‐emitting deciduous forest and predominantly non‐isoprene‐emitting agricultural landscapes. We find that anthropogenic interferences (or anthropogenic isoprene) contribute on average 22% of the PTR‐MS m/z 69 signal during summer daytime, whereas MVK + MACR interferences (m/z 71) are minor (7%). After removing these interferences, the observed isoprene and MVK + MACR abundances show pronounced seasonal cycles, reaching summertime maxima of >2500 pptv (1 h mean). The tall tower is impacted both by nearby and more distant regional isoprene sources, with daytime enhancements of isoprene (but little MVK + MACR) under southwest winds and enhancements of MVK + MACR (but little isoprene) at other times. We find that the GEOS‐Chem atmospheric model with the MEGANv2.1 (Model of Emissions of Gases and Aerosols from Nature version 2.1) biogenic inventory can reproduce the isoprene observations to within model uncertainty given improved land cover and temperature estimates. However, a 60% low model bias in MVK + MACR cannot be resolved, even across diverse model assumptions for NOx emissions, chemistry, atmospheric mixing, dry deposition, land cover, and potential measurement interferences. This implies that, while isoprene emissions in the immediate vicinity of the tall tower are adequately captured, they are underestimated across the broader region. We show that this region experiences a strong seasonal shift between VOC‐limited chemistry during the spring and fall and NOx‐limited or transitional chemistry during the summer, driven by the spatiotemporal distribution of isoprene emissions. Isoprene's role in causing these chemical shifts is likely underestimated due to the underprediction of its regional emissions.
Numerical simulation of the environmental impact of hydraulic fracturing of tight/shale gas reservoirs on near‐surface groundwater: Background, base cases, shallow reservoirs, short‐term gas, and water transport
Authors: Reagan Matthew T. , Moridis George J. , Keen Noel D. , Johnson Jeffrey N. 
Published: March 2015

AbstractHydrocarbon production from unconventional resources and the use of reservoir stimulation techniques, such as hydraulic fracturing, has grown explosively over the last decade. However, concerns have arisen that reservoir stimulation creates significant environmental threats through the creation of permeable pathways connecting the stimulated reservoir with shallower freshwater aquifers, thus resulting in the contamination of potable groundwater by escaping hydrocarbons or other reservoir fluids. This study investigates, by numerical simulation, gas and water transport between a shallow tight‐gas reservoir and a shallower overlying freshwater aquifer following hydraulic fracturing operations, if such a connecting pathway has been created. We focus on two general failure scenarios: (1) communication between the reservoir and aquifer via a connecting fracture or fault and (2) communication via a deteriorated, preexisting nearby well. We conclude that the key factors driving short‐term transport of gas include high permeability for the connecting pathway and the overall volume of the connecting feature. Production from the reservoir is likely to mitigate release through reduction of available free gas and lowering of reservoir pressure, and not producing may increase the potential for release. We also find that hydrostatic tight‐gas reservoirs are unlikely to act as a continuing source of migrating gas, as gas contained within the newly formed hydraulic fracture is the primary source for potential contamination. Such incidents of gas escape are likely to be limited in duration and scope for hydrostatic reservoirs. Reliable field and laboratory data must be acquired to constrain the factors and determine the likelihood of these outcomes.
Fast magnetosonic waves driven by shell velocity distributions
Authors: Min Kyungguk , Liu Kaijun 
Published: March 2015

AbstractUsing linear dispersion theory and particle‐in‐cell simulations, we explore the ion Bernstein instability driven by the shell‐type ion velocity distribution which is related to the excitation of fast magnetosonic waves in the terrestrial magnetosphere. We first demonstrate a novel idea to construct the shell velocity distribution out of multiple Maxwellian ring‐beam velocity distributions. Applying this technique, we find that the convergence of the linear theory instability can be achieved with only a moderate number of ring‐beam components. In order to prove that such an approximation is legitimate and the linear theory instabilities evaluated are indeed valid, we use the exact shell distribution to carry out a number of one dimensional particle‐in‐cell simulations corresponding to multiple wave propagation angles adjacent to the direction at which the most unstable waves are expected to grow. The agreement between the linear dispersion analysis and the simulation results is generally very good: enhanced waves are organized along the linear theory dispersion curves in the frequency‐wave number space, and relative wave amplitudes are ordered as the linear theory growth rates very well. However, the simulations show a few extra branches that are not expected from the linear dispersion analysis. A close examination of these extra branches suggests that they are not simulation artifacts and particularly related to the ring/shell‐type distributions with large ring/shell speed (v>∼1.5 vA, where vA is the Alfvén speed). In addition, our results show that substantial wave growth can occur at nonintegral harmonics of the proton cyclotron frequency at wave normal angles substantially far away from the perpendicular direction, which may provide an alternative explanation of the off‐harmonic peaks of some fast magnetosonic waves observed in space.