bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suomi NPP VIIRS prelaunch and on‐orbit geometric calibration and characterization
Authors: Wolfe Robert E. , Lin Guoqing , Nishihama Masahiro , Tewari Krishna P. , Tilton James C. , Isaacman Alice R. 
Published: October 2013

AbstractThe Visible Infrared Imaging Radiometer Suite (VIIRS) sensor was launched 28 October 2011 on the Suomi National Polar‐orbiting Partnership (SNPP) satellite. VIIRS has 22 spectral bands covering the spectrum between 0.412 µm and 12.01 µm, including 16 moderate resolution bands (M‐bands) with a nominal spatial resolution of 750 m at nadir, five imaging resolution bands (I‐bands) with a nominal spatial resolution of 375 m at nadir, and a day‐night band (DNB) with a near‐constant nominal 750 m spatial resolution throughout the scan. These bands are located in a visible and near‐infrared focal plane assembly (FPA), a shortwave and midwave infrared FPA, and a long‐wave infrared FPA. All bands, except the DNB, are coregistered for proper environmental data records retrievals. Observations from VIIRS instrument provide long‐term measurements of biogeophysical variables for climate research and polar satellite data stream for the operational community's use in weather forecasting and disaster relief and other applications. Well Earth‐located (geolocated) instrument data are important to retrieving accurate biogeophysical variables. This paper describes prelaunch pointing and alignment measurements, and the two sets of on‐orbit correction of geolocation errors, the first of which corrected error from 1300 m to within 75 m (20% I‐band pixel size) and the second of which fine‐tuned scan‐angle dependent errors, bringing VIIRS geolocation products to high maturity in one and a half years of the SNPP VIIRS on‐orbit operations. Prelaunch calibration and the on‐orbit characterization of sensor spatial impulse responses and band‐to‐band coregistration are also described.
Surface mass balance on Fimbul ice shelf, East Antarctica: Comparison of field measurements and large‐scale studies
Authors: Sinisalo Anna , Anschütz Helgard , Aasen Anne Tårånd , Langley Kirsty , von Deschwanden Angela , Kohler Jack , Matsuoka Kenichi , Hamran Svein‐ Erik , Øyan Mats‐Jørgen , Schlosser Elisabeth , Hagen Jon Ove , Nøst Ole Anders , Isaksson Elisabeth 
Published: October 2013

AbstractMany challenges remain for estimating the Antarctic ice sheet surface mass balance (SMB), which represents a major uncertainty in predictions of future sea‐level rise. Validating continental scale studies is hampered by the sparse distribution of in situ data. Here we present a 26 year mean SMB of the Fimbul ice shelf in East Antarctica between 1983–2009, and recent interannual variability since 2010. We compare these data to the results of large‐scale SMB studies for similar time periods, obtained from regional atmospheric modeling and remote sensing. Our in situ data include ground penetrating radar, firn cores, and mass balance stakes and provide information on both temporal and spatial scales. The 26 year mean SMB on the Fimbul ice shelf varies between 170 and 620 kg m−2 a−1 giving a regional average value of 310 ± 70 kg m−2 a−1. Our measurements indicate higher long‐term accumulation over large parts of the ice shelf compared to the large‐scale studies. We also show that the variability of the mean annual SMB, which can be up to 90%, can be a dominant factor in short‐term estimates. The results emphasize the importance of using a combination of ground‐based validation data, regional climate models, and remote sensing over a relevant time period in order to achieve a reliable SMB for Antarctica.
The evolving application of single‐port robotic surgery in general surgery
Authors: Qadan Motaz , Curet Myriam J. , Wren Sherry M. 
Published: October 2013

AbstractAdvances in the field of minimally invasive surgery have grown since the original advent of conventional multiport laparoscopic surgery. The recent development of single incision laparoscopic surgery remains a relatively novel technique, and has had mixed reviews as to whether it has been associated with lower pain scores, shorter hospital stays, and higher satisfaction levels among patients undergoing procedures through cosmetically‐appeasing single incisions. However, due to technical difficulties that arise from the clustering of laparoscopic instruments through a confined working space, such as loss of instrument triangulation, poor surgical exposure, and instrument clashing, uptake by surgeons without a specific interest and expertise in cutting‐edge minimally invasive approaches has been limited. The parallel use of robotic surgery with single‐port platforms, however, appears to counteract technical issues associated with single incision laparoscopic surgery through significant ergonomic improvements, including enhanced instrument triangulation, organ retraction, and camera localization within the surgical field. By combining the use of the robot with the single incision platform, the recognized challenges of single incision laparoscopic surgery are simplified, while maintaining potential advantages of the single‐incision minimally invasive approach. This review provides a comprehensive report of the evolving application single‐port robotic surgery in the field of general surgery today.
Development of the trigeminal motor neurons in parrots: Implications for the role of nervous tissue in the evolution of jaw muscle morphology
Authors: Tokita Masayoshi , Nakayama Tomoki 
Published: October 2013

ABSTRACTVertebrates have succeeded to inhabit almost every ecological niche due in large part to the anatomical diversification of their jaw complex. As a component of the feeding apparatus, jaw muscles carry a vital role for determining the mode of feeding. Early patterning of the jaw muscles has been attributed to cranial neural crest‐derived mesenchyme, however, much remains to be understood about the role of nonneural crest tissues in the evolution and diversification of jaw muscle morphology. In this study, we describe the development of trigeminal motor neurons in a parrot species with the uniquely shaped jaw muscles and compare its developmental pattern to that in the quail with the standard jaw muscles to uncover potential roles of nervous tissue in the evolution of vertebrate jaw muscles. In parrot embryogenesis, the motor axon bundles are detectable within the muscular tissue only after the basic shape of the muscular tissue has been established. This supports the view that nervous tissue does not primarily determine the spatial pattern of jaw muscles. In contrast, the trigeminal motor nucleus, which is composed of somata of neurons that innervate major jaw muscles, of parrot is more developed compared to quail, even in embryonic stage where no remarkable interspecific difference in both jaw muscle morphology and motor nerve branching pattern is recognized. Our data suggest that although nervous tissue may not have a large influence on initial patterning of jaw muscles, it may play an important role in subsequent growth and maintenance of muscular tissue and alterations in cranial nervous tissue development may underlie diversification of jaw muscle morphology. J. Morphol. 275:191–205, 2014. © 2013 Wiley Periodicals, Inc.
Lung injury induced by secondhand smoke exposure detected with hyperpolarized helium‐3 diffusion MR
Authors: Wang Chengbo , Mugler John P. , de Lange Eduard E. , Patrie James T. , Mata Jaime F. , Altes Talissa A. 
Published: October 2013

PurposeTo determine whether helium‐3 diffusion MR can detect the changes in the lungs of healthy nonsmoking individuals who were regularly exposed to secondhand smoke.Materials and MethodsThree groups were studied (age: 59 ± 9 years): 23 smokers, 37 exposure‐to‐secondhand‐smoke subjects, and 29 control subjects. We measured helium‐3 diffusion values at diffusion times from 0.23 to 1.97 s.ResultsOne‐way analysis of variance revealed that the mean area under the helium‐3 diffusion curves (ADC AUC) of the smokers was significantly elevated compared with the controls and to the exposure‐to‐secondhand‐smoke subjects (P < 0.001 both). No difference between the mean ADC AUC of the exposure‐to‐secondhand‐smoke subjects and that of the controls was found (P = 0.115). However, application of a receiver operator characteristic‐derived rule to classify subjects as either a “control” or a “smoker,” based on ADC AUC, revealed that 30% (11/37) of the exposure‐to‐secondhand subjects were classified as “smokers” indicating an elevation of the ADC AUC.ConclusionUsing helium‐3 diffusion MR, elevated ADC values were detected in 30% of nonsmoking healthy subjects who had been regularly exposed to secondhand smoke, supporting the concept that, in susceptible individuals, secondhand smoke causes mild lung damage. J. Magn. Reson. Imaging 2014;39:77–84. © 2013 Wiley Periodicals, Inc.
Breast MRI at 7 Tesla with a bilateral coil and robust fat suppression
Authors: Brown Ryan , Storey Pippa , Geppert Christian , McGorty KellyAnne , Klautau Leite Ana Paula , Babb James , Sodickson Daniel K. , Wiggins Graham C. , Moy Linda 
Published: October 2013

PurposeTo develop a bilateral coil and fat suppressed T1‐weighted sequence for 7 Tesla (T) breast MRI.Materials and MethodsA dual‐solenoid coil and three‐dimensional (3D) T1w gradient echo sequence with B1+ insensitive fat suppression (FS) were developed. T1w FS image quality was characterized through image uniformity and fat–water contrast measurements in 11 subjects. Signal‐to‐noise ratio (SNR) and flip angle maps were acquired to assess the coil performance. Bilateral contrast‐enhanced and unilateral high resolution (0.6 mm isotropic, 6.5 min acquisition time) imaging highlighted the 7T SNR advantage.ResultsReliable and effective FS and high image quality was observed in all subjects at 7T, indicating that the custom coil and pulse sequence were insensitive to high‐field obstacles such as variable tissue loading. 7T and 3T image uniformity was similar (P = 0.24), indicating adequate 7T B1+ uniformity. High 7T SNR and fat–water contrast enabled 0.6 mm isotropic imaging and visualization of a high level of fibroglandular tissue detail.Conclusion7T T1w FS bilateral breast imaging is feasible with a custom radiofrequency (RF) coil and pulse sequence. Similar image uniformity was achieved at 7T and 3T, despite different RF field behavior and variable coil–tissue interaction due to anatomic differences that might be expected to alter magnetic field patterns. J. Magn. Reson. Imaging 2014;39:540–549. © 2013 Wiley Periodicals, Inc.
Impact of repetitive exposure to strong static magnetic fields on pregnancy and embryonic development of mice
Authors: Zahedi Yasmin , Zaun Gregor , Maderwald Stefan , Orzada Stephan , Pütter Carolin , Scherag André , Winterhager Elke , Ladd Mark E. , Grümmer Ruth 
Published: October 2013

PurposeTo evaluate possible risks of strong static magnetic fields for embryo implantation, gestation, organogenesis, and embryonic development.Materials and MethodsPregnant mice were exposed for 75 minutes daily during the entire course of pregnancy at the bore entrance, representing the position of medical staff, and at the isocenter, representing the position of patients, of a 1.5 T and a 7 T human MRI scanner.ResultsNo effect of static magnetic field strength was observed with regard to pregnancy rate, duration of pregnancy, litter size, still births, malformations, sex distribution, or postpartum death of offspring. During the first 8 weeks postnatal, mice exposed in utero to a magnetic field strength of 1.5 T or stronger showed a slight delay in weight gain and in time to eye opening compared to controls.ConclusionDaily exposure to strong magnetic fields during pregnancy had no deleterious effect on offspring; however, a developmental retardation could be observed postnatally with regard to weight gain and eye opening. J. Magn. Reson. Imaging 2014;39:691–699. © 2013 Wiley Periodicals, Inc.
Correction of B0‐Distortions in Echo‐Planar‐Imaging–Based Perfusion‐Weighted MRI
Authors: Vardal Jonas , Salo Raimo A. , Larsson Christopher , Dale Anders M. , Holland Dominic , Groote Inge Rasmus , Bjørnerud Atle 
Published: October 2013

PurposeTo evaluate and quantify a scheme for correcting susceptibility artifacts in spin‐echo echo‐planar‐imaging–based dynamic susceptibility contrast (DSC) perfusion MRI of high‐grade gliomas at 3 Tesla.Materials and MethodsSixteen patients with a total of 78 scans were studied. DSC‐MRI images were corrected using a displacement map generated from opposite phase‐encoding polarity images. Two methods were used for quantification in the correction: (i) linear regression of pixel‐by‐pixel comparisons, performed both globally and relative to the anterior and posterior commissure plane (AC‐PC plane), of T2‐weighted images with both corrected and uncorrected raw DSC images; and (ii) counting significant (>2.0) normalized cerebral blood volume (nCBV) pixels from perfusion maps in the tumor region of interest.ResultsSixty‐four of 78 datasets showed significant differences in the coefficient of correlation (r2) values. The difference between corrected and uncorrected r2 values was positive in all but one patient. Correction of B0‐ distortion significantly improved r2 in slices around the AC‐PC plane. In 62% of the datasets, we observed an increased number of significant pixels in the corrected nCBV maps; 36% showed more significant pixels in uncorrected nCBV maps; 1% showed no difference.ConclusionDistortion correction of DSC‐MRI may provide improved accuracy compared with uncorrected data, especially for tumors located below the corpus callosum and near the frontal sinuses. J. Magn. Reson. Imaging 2014;39:722–728. © 2013 Wiley Periodicals, Inc.
Dynamic gadoxetate‐enhanced MRI for the assessment of total and segmental liver function and volume in primary sclerosing cholangitis
Authors: Nilsson Henrik , Blomqvist Lennart , Douglas Lena , Nordell Anders , Jacobsson Hans , Hagen Karin , Bergquist Annika , Jonas Eduard 
Published: October 2013

PurposeTo evaluate dynamic hepatocyte‐specific contrast‐enhanced MRI (DHCE‐MRI) for the assessment of global and segmental liver volume and function in patients with primary sclerosing cholangitis (PSC), and to explore the heterogeneous distribution of liver function in this patient group.Materials and MethodsTwelve patients with primary sclerosing cholangitis (PSC) and 20 healthy volunteers were examined using DHCE‐MRI with Gd‐EOB‐DTPA. Segmental and total liver volume were calculated, and functional parameters (hepatic extraction fraction [HEF], input relative blood‐flow [irBF], and mean transit time [MTT]) were calculated in each liver voxel using deconvolutional analysis. In each study subject, and incongruence score (IS) was constructed to describe the mismatch between segmental function and volume. Among patients, the liver function parameters were correlated to bile duct obstruction and to established scoring models for liver disease.ResultsLiver function was significantly more heterogeneously distributed in the patient group (IS 1.0 versus 0.4). There were significant correlations between biliary obstruction and segmental functional parameters (HEF rho −0.24; irBF rho −0.45), and the Mayo risk score correlated significantly with the total liver extraction capacity of Gd‐EOB‐DTPA (rho −0.85).ConclusionThe study demonstrates a new method to quantify total and segmental liver function using DHCE‐MRI in patients with PSC. J. Magn. Reson. Imaging 2014;39:879–886. © 2013 Wiley Periodicals, Inc.
Method to create regional mechanical dyssynchrony maps from short‐axis cine steady‐state free‐precession images
Authors: Suever Jonathan D. , Fornwalt Brandon K. , Neuman Lee R. , Delfino Jana G. , Lloyd Michael S. , Oshinski John N. 
Published: October 2013

PurposeTo develop a robust method to assess regional mechanical dyssynchrony from cine short‐axis MR images. Cardiac resynchronization therapy (CRT) is an effective treatment for patients with heart failure and evidence of left‐ventricular (LV) dyssynchrony. Patient response to CRT is greatest when the LV pacing lead is placed in the most dyssynchronous segment. Existing techniques for assessing regional dyssynchrony require difficult acquisition and/or postprocessing. Our goal was to develop a widely applicable and robust method to assess regional mechanical dyssynchrony.Materials and MethodsUsing the endocardial boundary, radial displacement curves (RDCs) were generated throughout the LV. Cross‐correlation was used to determine the delay time between each RDC and a patient‐specific reference. Delay times were projected onto the American Heart Association 17‐segment model creating a regional dyssynchrony map. Our method was tested in 10 normal individuals and 10 patients enrolled for CRT (QRS > 120 ms, NYHA III‐IV, EF < 35%).ResultsDelay times over the LV were 23.9 ± 33.8 ms and 93.1 ± 99.9 ms (P < 0.001) in normal subjects and patients, respectively. Interobserver reproducibility for segment averages was 6.8 ± 39.3 ms and there was 70% agreement in identifying the latest contracting segment.ConclusionWe have developed a method that can reliably calculate regional delay times from cine steady‐state free‐precession (SSFP) images. Maps of regional dyssynchrony could be used to identify the latest‐contracting segment to assist in CRT lead implantation. J. Magn. Reson. Imaging 2014;39:958–965. © 2013 Wiley Periodicals, Inc.
Fully automated tool to identify the aorta and compute flow using phase‐contrast MRI: Validation and application in a large population based study
Authors: Goel Akshay , McColl Roderick , King Kevin S. , Whittemore Anthony , Peshock Ronald M. 
Published: October 2013

PurposeTo assess if fully automated localization of the aorta can be achieved using phase contrast (PC) MR images.Materials and MethodsPC cardiac‐gated MR images were obtained as part of a large population‐based study. A fully automated process using the Hough transform was developed to localize the ascending aorta (AAo) and descending aorta (DAo). The study was designed to validate this technique by determining: (i) its performance in localizing the AAo and DAo; (ii) its accuracy in generating AAo flow volume and DAo flow volume; and (iii) its robustness on studies with pathological abnormalities or imaging artifacts.ResultsThe algorithm was applied successfully on 1884 participants. In the randomly selected 50‐study validation set, linear regression shows an excellent correlation between the automated (A) and manual (M) methods for AAo flow (r = 0.99) and DAo flow (r = 0.99). Bland‐Altman difference analysis demonstrates strong agreement with minimal bias for: AAo flow (mean difference [A‐M] = 0.47 ± 2.53 mL), and DAo flow (mean difference [A‐M] = 1.74 ± 2.47 mL).ConclusionA robust fully automated tool to localize the aorta and provide flow volume measurements on phase contrast MRI was validated on a large population‐based study. J. Magn. Reson. Imaging 2014;40:221–228. © 2013 Wiley Periodicals, Inc.
Three‐dimensional assessment of lung tissue density using a clinical ultrashort echo time at 3 tesla: A feasibility study in healthy subjects
Authors: Lederlin Mathieu , Crémillieux Yannick 
Published: October 2013

PurposeTo implement and assess the performance of three‐dimensional (3D) ultra‐short echo (UTE) time for evaluating lung tissue density changes induced by gravity dependence and lung inflation.Materials and MethodsTwelve healthy volunteers were imaged by 3D UTE at 3 Tesla, during free‐breathing and breathholding of the subjects. MR signal intensities were measured in lung tissue and muscle regions. The variations of MR lung signal intensity and lung water content were evaluated as a function of lung inflation and anterior/posterior position.ResultsSNR in lung tissue ranged between 35 for free‐breathing acquisitions and 7 for breathhold acquisitions at functional residual capacity. Lung‐to‐muscle signal ratios decreased from 0.58 in posterior areas to 0.34 in anterior areas. The average water content measured in lungs was equal to 34% and 58% in gravitationally nondependent and dependent regions of interest.ConclusionThe 3D UTE lung MRI provides signal within lung parenchyma and can be used to assess lung tissue density. J. Magn. Reson. Imaging 2014;40:839–847. © 2013 Wiley Periodicals, Inc.
Residual viremia in patients on antiretroviral therapy incorporating nevirapine is not associated with the gag‐specific cellular immune response
Authors: McIlroy Dorian , Allavena Clotilde , Rodallec Audrey , Billaud Eric , Ferré Virginie , Raffi François 
Published: October 2013

AbstractTo determine whether residual plasma viremia in HIV+ patients on nevirapine‐including antiretroviral therapy (ART) is related to anti‐HIV cellular immune responses, a case–control study was conducted comparing residual viremia in patients with detectable and undetectable Gag‐specific T‐cell responses. Gag‐specific responses were measured by IFN‐γ ELISpot. Residual viremia was determined at two consecutive hospital visits by an ultra‐sensitive technique with a detection limit of 2 copies/ml. Median residual viremia was not different in patients with a positive Gag‐specific ELISpot (n = 25) compared to those with a negative Gag‐specific ELISpot (n = 30, P = 0.91). Ten of 25 (40%) patients with consistent detectable residual viremia and 4 of 12 (33%) patients with consistently undetectable residual viremia had a positive Gag‐specific ELISpot. Undetectable residual viremia was associated with the duration of ART including nevirapine (P < 0.05), but not with the Gag‐specific ELISpot response. Gag‐specific CTL in patients on ART therefore appear to have no impact on the virus‐producing cells that are responsible for residual viremia during ART. J. Med. Virol. 86:1087–1092, 2014. © 2013 Wiley Periodicals, Inc.
Local and global spatio‐temporal dynamics of HIV‐1 subtype F1
Authors: Lai Alessia , Ciccozzi Massimo , Franzetti Marco , Simonetti Francesco R. , Bozzi Giorgio , Binda Francesca , Rosi Andrea , Bonora Stefano , De Luca Andrea , Balotta Claudia , Zehender Gianguglielmo 
Published: October 2013

AbstractPrevious studies have attempted to explore the origin of the F1 subtype, but the precise origin of the Romanian and South American F1 variants remains controversial. As the F1 subtype is the most frequent non‐B variant among Europeans residing in Italy, the aim of this study was to estimate its phylogeography in order to reconstruct its origin and route of dispersion. The phylogeographical analyses, which were made using the Bayesian Markov Chain Monte Carlo approach and BEAST software, revealed two significant clades: the first included all of the Romanian strains together with a few Italian and four African isolates; the second encompassed all of the South American sequences and the large majority of Italian variants. By putting the African reference sequences into two discrete groups based on specific countries, phylogeographic analysis indicated that the F1 epidemic originated in Cameroon/Democratic Republic of Congo in the early 1940s, and was exported to South America 10 years later. Subsequently, the F1 virus spread to Angola and, from there, was exported to Romania in the early 1960s. It reached Italy in the 1970s from South America and Romania. The South American and Romanian variants of F1 have different African countries of origin and different temporal spreads. The South American variant seems to be characterized by multiple introduction events, whereas the Romanian strain probably spread as a result of a single entry. Two different pathways from South America and Romania led the F1 variant to Italy in the 1970s. J. Med. Virol. 86:186–192, 2014. © 2013 Wiley Periodicals, Inc.