bluuebunny/crossref_metadata_2025_split huggingface dataset:
Total duration of antimicrobial therapy in veterans hospitalized with uncomplicated pneumonia: Results of a national medication utilization evaluation
Authors: Madaras‐Kelly Karl J. , Burk Muriel , Caplinger Christina , Bohan Jefferson G. , Neuhauser Melinda M. , Goetz Matthew Bidwell , Zhang Rongping , Cunningham Francesca E. ,   for the Pneumonia Duration of Therapy Medication Utilization Evaluation Group
Published: August 2016

OBJECTIVEPractice guidelines recommend the shortest duration of antimicrobial therapy appropriate to treat uncomplicated pneumonia be prescribed to reduce the emergence of resistant pathogens. A national evaluation was conducted to assess the duration of therapy for pneumonia.DESIGNRetrospective medication utilization evaluation.SETTINGThirty Veterans Affairs medical centers.PATIENTSInpatients discharged with a diagnosis of pneumonia.MEASUREMENTSA manual review of electronic medical records of inpatients discharged with uncomplicated community‐acquired pneumonia (CAP) or healthcare‐associated pneumonia (HCAP) was conducted. Appropriate CAP therapy duration was defined as at least 5 days, and up to 3 additional days beginning the first day the patient achieved clinical stability criteria; the appropriate HCAP therapy duration was defined as 8 days. The duration of antimicrobial therapy for intravenous (IV) and oral (PO) inpatient administration, PO therapy dispensed upon discharge, Clostridium difficile infection (CDI), hospital readmission, and death rates were measured.RESULTSOf 3881 pneumonia admissions, 1739 met inclusion criteria (CAP [n = 1195]; HCAP [n = 544]). Overall, 13.9% of patients (CAP [6.9%], HCAP [29.0%]) received therapy duration consistent with guideline recommendations. The median (interquartile range) days of therapy were 4 days (3–6 days), 1 day (0–3 days), and 6 days (4–8 days) for inpatient IV, inpatient PO, and outpatient PO antimicrobials, respectively. CDI was rare but more common in patients who received therapy duration consistent with guidelines. Therapy duration was not associated with the readmission or mortality rate.CONCLUSIONSAntimicrobials were commonly prescribed for a longer duration than guidelines recommend. The majority of excessive therapy was completed upon discharge, identifying the need for strategies to curtail unnecessary use postdischarge. Journal of Hospital Medicine 2015;11:832–839. © 2015 Society of Hospital Medicine
Apparent diffusion coefficient measurement in glioma: Influence of region‐of‐interest determination methods on apparent diffusion coefficient values, interobserver variability, time efficiency, and diagnostic ability
Authors: Han Xu , Suo Shiteng , Sun Yawen , Zu Jinyan , Qu Jianxun , Zhou Yan , Chen Zengai , Xu Jianrong 
Published: August 2016

PurposeTo compare four methods of region‐of‐interest (ROI) placement for apparent diffusion coefficient (ADC) measurements in distinguishing low‐grade gliomas (LGGs) from high‐grade gliomas (HGGs).Materials and MethodsTwo independent readers measured ADC parameters using four ROI methods (single‐slice [single‐round, five‐round and freehand] and whole‐volume) on 43 patients (20 LGGs, 23 HGGs) who had undergone 3.0 Tesla diffusion‐weighted imaging and time required for each method of ADC measurements was recorded. Intraclass correlation coefficients (ICCs) were used to assess interobserver variability of ADC measurements. Mean and minimum ADC values and time required were compared using paired Student's t‐tests. All ADC parameters (mean/minimum ADC values of three single‐slice methods, mean/minimum/standard deviation/skewness/kurtosis/the10th and 25th percentiles/median/maximum of whole‐volume method) were correlated with tumor grade (low versus high) by unpaired Student's t‐tests. Discriminative ability was determined by receiver operating characteristic curves.ResultsAll ADC measurements except minimum, skewness, and kurtosis of whole‐volume ROI differed significantly between LGGs and HGGs (all P < 0.05). Mean ADC value of single‐round ROI had the highest effect size (0.72) and the greatest areas under the curve (0.872). Three single‐slice methods had good to excellent ICCs (0.67–0.89) and the whole‐volume method fair to excellent ICCs (0.32–0.96). Minimum ADC values differed significantly between whole‐volume and single‐round ROI (P = 0.003) and, between whole‐volume and five‐round ROI (P = 0.001). The whole‐volume method took significantly longer than all single‐slice methods (all P < 0.001).ConclusionADC measurements are influenced by ROI determination methods. Whole‐volume histogram analysis did not yield better results than single‐slice methods and took longer. Mean ADC value derived from single‐round ROI is the most optimal parameter for differentiating LGGs from HGGs.Level of Evidence: 3J. Magn. Reson. Imaging 2017;45:722–730.
Susceptibility‐weighted imaging using inter‐echo‐variance channel combination for improved contrast at 7 tesla
Authors: Hosseini Zahra , Liu Junmin , Solovey Igor , Menon Ravi S. , Drangova Maria 
Published: August 2016

PurposeTo implement and optimize a new approach for susceptibility‐weighted image (SWI) generation from multi‐echo multi‐channel image data and compare its performance against optimized traditional SWI pipelines.Materials and MethodsFive healthy volunteers were imaged at 7 Tesla. The inter‐echo‐variance (IEV) channel combination, which uses the variance of the local frequency shift at multiple echo times as a weighting factor during channel combination, was used to calculate multi‐echo local phase shift maps. Linear phase masks were combined with the magnitude to generate IEV‐SWI. The performance of the IEV‐SWI pipeline was compared with that of two accepted SWI pipelines–channel combination followed by (i) Homodyne filtering (HPH‐SWI) and (ii) unwrapping and high‐pass filtering (SVD‐SWI). The filtering steps of each pipeline were optimized. Contrast‐to‐noise ratio was used as the comparison metric. Qualitative assessment of artifact and vessel conspicuity was performed and processing time of pipelines was evaluated.ResultsThe optimized IEV‐SWI pipeline (σ = 7 mm) resulted in continuous vessel visibility throughout the brain. IEV‐SWI had significantly higher contrast compared with HPH‐SWI and SVD‐SWI (P < 0.001, Friedman nonparametric test). Residual background fields and phase wraps in HPH‐SWI and SVD‐SWI corrupted the vessel signal and/or generated vessel‐mimicking artifact. Optimized implementation of the IEV‐SWI pipeline processed a six‐echo 16‐channel dataset in under 10 min.ConclusionIEV‐SWI benefits from channel‐by‐channel processing of phase data and results in high contrast images with an optimal balance between contrast and background noise removal, thereby presenting evidence of importance of the order in which postprocessing techniques are applied for multi‐channel SWI generation.Level of Evidence: 2J. Magn. Reson. Imaging 2017;45:1113–1124
Comparison of T2, T1rho, and diffusion metrics in assessment of liver fibrosis in rats
Authors: Zhang Hui , Yang Qihua , Yu Taihui , Chen Xiaodong , Huang Jingwen , Tan Cui , Liang Biling , Guo Hua 
Published: August 2016

PurposeTo evaluate the value of T2, T1rho, and diffusion metrics in assessment of liver fibrosis in rats.Materials and MethodsLiver fibrosis in a rat model (n = 72) was induced by injection of carbon tetrachloride (CCl4) at 3T. T2, T1rho, and diffusion parameters (apparent diffusion coefficient (ADC), Dtrue) via spin echo (SE) diffusion‐weighted imaging (DWI) and stimulated echo acquisition mode (STEAM) DWI with three diffusion times (DT: 80, 106, 186 msec) were obtained in surviving rats with hepatic fibrosis (n = 52) and controls (n = 8). Liver fibrosis stage (F0–F6) was identified based on pathological results using the traditional liver fibrosis staging method for rodents. Nonparametric statistical methods and receiver operating characteristic (ROC) curve analysis were employed to determine the diagnostic accuracy.ResultsMean T2, T1rho, ADC, and Dtrue with DT = 186 msec correlated with the severity of fibrosis with r = 0.73, 0.83, −0.83, and −0.85 (all P < 0.001), respectively. The average areas under the ROC curve at different stages for T1rho and diffusion parameters (DT = 186 msec) were larger than those of T2 and SE DWI (0.92, 0.92, and 0.92 vs. 0.86, 0.82, and 0.83). The corresponding average sensitivity and specificity for T1rho and diffusion parameters with a long DT were larger (89.35 and 88.90, 88.36 and 89.97, 90.16 and 87.13) than T2 and SE DWI (90.28 and 79.93, 85.30 and 77.64, 78.21 and 82.41). The performances of T1rho and Dtrue (DT = 186 msec) were comparable (average AUC: 0.92 and 0.92).ConclusionAmong the evaluated sequences, T1rho and STEAM DWI with a long DT may serve as superior imaging biomarkers for assessing liver fibrosis and monitoring disease severity.Level of Evidence: 1J. Magn. Reson. Imaging 2017;45:741–750.
Gap filling and homogenization of climatological datasets in the headwater region of the Upper Blue Nile Basin, Ethiopia
Authors: Woldesenbet Tekalegn Ayele , Elagib Nadir Ahmed , Ribbe Lars , Heinrich Jürgen 
Published: August 2016

ABSTRACTLong‐term time series of climatological data measured at meteorological stations provide one of the most authentic annals of climate in the past. However, there are a host of factors that affect measurements of climate parameters and make the data unsuitable for direct use and analysis. Serial completion and homogenization thus have to be undertaken in order to draw valid conclusions about the climate, or to apply the time series in impact studies. This study reports on gap filling and homogenization results of climatological elements in the headwater region of the Upper Blue Nile Basin from 1980 to 2013. Firstly, approaches for reconstruction of the time series from neighboring stations using different techniques were compared and selected. Neighboring stations were selected based on horizontal distance and coefficient of correlation. Secondly, the reconstructed time series were homogenized using Multiple Analysis of Series for Homogenization (MASH). The results show improved spatial coherence of the final data series. Higher spatial coherence was revealed for maximum temperature than for minimum temperature and rainfall. For rainfall and minimum and maximum temperatures, the coefficient of correlation weighting method outperforms other candidate methods, such as the normal ratio method (NRM), the modified NRM, and the inverse distance weighting method. Rainfall series for half of the stations considered were found to be homogeneous, and thus inhomogeneity corrections were not applied. Inhomogeneity in the remaining stations either underestimates or overestimates annual rainfall series. All stations revealed inhomogeneity in the mean annual maximum and minimum temperature series. These serially complete and homogenized data on rainfall, and minimum and maximum temperatures of the present study can be used for climate change and hydrological studies in the basin.
Innovative trend analysis of annual and seasonal rainfall and extreme values in Shaanxi, China, since the 1950s
Authors: Wu Hao , Qian Hui 
Published: August 2016

ABSTRACTRainfall is a primary component of the water cycle, and its variability is associated with drought and flood events. This study investigates the trends in annual and seasonal rainfall at 14 rainfall stations in Shaanxi Province, China, using an innovative trend analysis (ITA), Mann–Kendall test and linear regression analysis. Moreover, using ITA, annual rainfall is analysed for different rainfall intensities, and seasonal rainfall is analysed for extreme values. The results show non‐uniform trends in rainfall intensities on a regional and seasonal scale. Annual rainfall shows a significant decreasing trend in the Wei River Basin and north of the Loess Plateau. Overall, the trend is reinforced with the increase of rainfall intensity. A few stations show significant trends in seasonal rainfall. Spring rainfall is the major contributor to the decline in annual rainfall. Heavy rainfall (more than 90th percentile) in summer exhibits a marked downward trend mainly in the basin, which makes it possible for flooding to abate along the Wei River. Light rainfall (less than 10th percentile) shows a prevailing increasing trend in summer, but a decreasing trend in other seasons. From north to south, the seasonal trends become clearer and stronger. In terms of management, more attention should be paid to autumn droughts in the Wei River Basin. A quantitative measurement of a trend for ITA is proposed. Comparison of the three methods endorses the ITA method. Moreover, the ITA shows many advantages, such as graphical results and for observing sub‐trends. It is hoped that this study can provide support for water resources planning, for coping with droughts and floods and for future development of the ITA method.
Validation of topsoil texture derived from agricultural soil maps by current dense soil sampling
Authors: Stępień Michał , Gozdowski Dariusz , Samborski Stanisław , Dobers Eike Stefan , Szatyłowicz Jan , Chormański Jarosław 
Published: August 2016

AbstractAgricultural soil maps were created to facilitate the management of fields. Such maps, at very large scale (1:5000), cover almost the entire agricultural land in Poland. These maps can be very useful for precision field management. However, they were prepared about 40–50 years ago using old mapping techniques with mainly field (organoleptic) examination of soil. For this reason it is necessary to verify agreement between such maps with the current soil status. In the case of detection of disagreements it is important to identify the causes and propose methods for improving soil maps. Only few studies were made in this aspect. The soil texture (ST) of the upper layer, as presented on the agricultural soil maps from the 1960s and 1970s, was compared with the actual ST of the same four fields in northern and central Poland. For laboratory ST determination, soil samples were collected in a dense sampling network. On average, the agreement of the ST presented on the agricultural soil maps and determined in this study was classified as medium for three fields and good for one field. However, the presence of field areas with poor agreement between the ST determined in this study and that shown on the agricultural maps was detected in all investigated fields. Identified causes for this comprised imprecision of ST determination using the organoleptic method, the generalization of the soil quality maps, and erosion processes during the years between soil mapping and this investigation. The improvement of ST presentation on the large scale soil maps might be achieved by quite denser soil sampling for ST analysis supported by ECa, yield and NDVI maps.
Neural Correlates of Trait Rumination During an Emotion Interference Task in Women With PTSD
Authors: Buchholz Katherine R. , Bruce Steven E. , Koucky Ellen M. , Artime Tiffany M. , Wojtalik Jessica A. , Brown Wilson J. , Sheline Yvette I. 
Published: August 2016

AbstractRumination, defined as repetitive, negative, self‐focused thinking, is hypothesized to be a transdiagnostic factor that is associated with depression, anxiety, and posttraumatic stress disorder (PTSD). Theory has suggested that in individuals with PTSD, rumination serves as a cognitive avoidance factor that contributes to the maintenance of symptoms by inhibiting the cognitive and emotional processing of the traumatic event, subsequently interfering with treatment engagement and outcome. Little is known about the neural correlates of rumination in women with PTSD. The current study utilized functional magnetic resonance imaging (fMRI) to examine neural correlates during an emotion interference task of self‐reported rumination in women with PTSD. Women with PTSD (39 participants) were recruited at a university‐based trauma clinic and completed a clinical evaluation that included measures of PTSD symptoms, rumination, and depressive symptoms, as well as a neuroimaging session in which the participants were administered an emotion interference task. There was a significant relationship between self‐reported rumination and activity in the right orbital frontal cortex, BA 11; t(37) = 5.62, p = .004, k = 46 during the task. This finding suggested that women with PTSD, who had higher levels of rumination, may experience greater difficulty inhibiting negative emotional stimuli compared to women with lower levels of rumination.
Predictive Models for the Free Energy of Hydrogen Bonded Complexes with Single and Cooperative Hydrogen Bonds
Authors: Glavatskikh Marta , Madzhidov Timur , Solov'ev Vitaly , Marcou Gilles , Horvath Dragos , Varnek Alexandre 
Published: August 2016

AbstractIn this work, we report QSPR modeling of the free energy ΔG of 1 : 1 hydrogen bond complexes of different H‐bond acceptors and donors. The modeling was performed on a large and structurally diverse set of 3373 complexes featuring a single hydrogen bond, for which ΔG was measured at 298 K in CCl4. The models were prepared using Support Vector Machine and Multiple Linear Regression, with ISIDA fragment descriptors. The marked atoms strategy was applied at fragmentation stage, in order to capture the location of H‐bond donor and acceptor centers. Different strategies of model validation have been suggested, including the targeted omission of individual H‐bond acceptors and donors from the training set, in order to check whether the predictive ability of the model is not limited to the interpolation of H‐bond strength between two already encountered partners. Successfully cross‐validating individual models were combined into a consensus model, and challenged to predict external test sets of 629 and 12 complexes, in which donor and acceptor formed single and cooperative H‐bonds, respectively. In all cases, SVM models outperform MLR. The SVM consensus model performs well both in 3‐fold cross‐validation (RMSE=1.50 kJ/mol), and on the external test sets containing complexes with single (RMSE=3.20 kJ/mol) and cooperative H‐bonds (RMSE=1.63 kJ/mol).
Prospective head motion correction using FID‐guided on‐demand image navigators
Authors: Waszak Maryna , Falkovskiy Pavel , Hilbert Tom , Bonnier Guillaume , Maréchal Bénédicte , Meuli Reto , Gruetter Rolf , Kober Tobias , Krueger Gunnar 
Published: August 2016

PurposeWe suggest a motion correction concept that employs free‐induction‐decay (FID) navigator signals to continuously monitor motion and to guide the acquisition of image navigators for prospective motion correction following motion detection.MethodsMotion causes out‐of‐range signal changes in FID time series that, and in this approach, initiate the acquisition of an image navigator. Co‐registration of the image navigator to a reference provides rigid‐body‐motion parameters to facilitate prospective motion correction. Both FID and image navigator are integrated into a prototype magnetization‐prepared rapid gradient‐echo (MPRAGE) sequence. The performance of the method is investigated using image quality metrics and the consistency of brain volume measurements.ResultsTen healthy subjects were scanned (a) while performing head movements (nodding, shaking, and moving in z‐direction) and (b) to assess the co‐registration performance. Mean absolute errors of 0.27 ± 0.38 mm and 0.19 ± 0.24° for translation and rotation parameters were measured. Image quality was qualitatively improved after correction. Significant improvements were observed in automated image quality measures and for most quantitative brain volume computations after correction.ConclusionThe presented method provides high sensitivity to detect head motion while minimizing the time invested in acquiring navigator images. Limits of this implementation arise from temporal resolution to detect motion, false‐positive alarms, and registration accuracy. Magn Reson Med 78:193–203, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Suitable reference tissues for quantitative susceptibility mapping of the brain
Authors: Straub Sina , Schneider Till M. , Emmerich Julian , Freitag Martin T. , Ziener Christian H. , Schlemmer Heinz‐Peter , Ladd Mark E. , Laun Frederik B. 
Published: August 2016

PurposeSince quantitative susceptibility mapping (QSM) quantifies magnetic susceptibility relative to a reference value, a suitable reference tissue has to be available to compare different subjects and stages of disease.MethodsTo find such a suitable reference tissue for QSM of the brain, melanoma patients with and without brain metastases were measured. Twelve reference regions were chosen and assessed for stability of susceptibility values with respect to multiple intra‐individual and inter‐individual measurements, age, and stage of disease.ResultsCerebrospinal fluid (CSF), the internal capsule and one region in the splenium of the corpus callosum are the regions with the smallest standard deviations of the mean susceptibility value. The mean susceptibility is 0.010 ± 0.014 ppm for CSF in the atrium of the lateral ventricles (csfpost), −0.060 ± 0.019 ppm for the posterior limb of the internal capsule (ci2), and −0.008 ± 0.019 ppm for the splenium of the corpus callosum. csfpost and ci2 show nearly no dependence on age or stage of disease, whereas some other regions, e.g., the red nucleus, show moderate dependence on age or disease.ConclusionThe internal capsule and CSF appear to be the most suitable reference regions for QSM of the brain in the melanoma patients studied. Both showed virtually no dependence on age or disease and small variations among patients. Magn Reson Med 78:204–214, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Tumor Volume and Clinical Failure in High‐Risk Prostate Cancer Patients Treated With Radical Prostatectomy
Authors: Castiglione Fabio , Dell'Oglio Paolo , Tosco Lorenzo , Everaerts Wouter , Albersen Maarten , Hakim Lukman , Van den Broeck Thomas , Moris Lisa , Claessens Frank , Briganti Alberto , Montorsi Francesco , Van Poppel Hein , Joniau Steven ,   European Multicenter Prostate Cancer Clinical and Translational Research Group (EMPaCT)
Published: August 2016

INTRODUCTIONTo identify the most significant cut‐off of tumor volume (TV) for prediction of clinical failure (CF) among high‐risk prostate cancer (hPCa) patients.METHODSWithin a multi‐institutional cohort, 262 patients treated with radical prostatectomy (RP) for hPCa were identified. CF was defined as local recurrence or distant metastases. A time dependent ROC curve was used to evaluate the area under the curve (AUC) using TV as single marker to predict clinical failure at 10 years. We searched for the TV cut off value with the highest combined sensitivity and specificity predicting CF. Three multivariable Cox regression analyses (MVA) tested the predictors of CF after RP. Predictors of the model 1 were pre‐operative PSA, pathologic stage (PT), pathologic Gleason sum (GS), surgical margin status, and lymph node invasion. Predictors of the models 2 and 3 were the same of model 1 plus TV as a continuous or dichotomous variable using the defined cutoff, respectively. Validation (leave‐one‐out‐cross‐validation‐LOOCV) of each model was performed.RESULTSOverall, 46 (17.6%) patients experienced CF. The TV value was 6.29 ml. In MVA of models 2 and 3, PT and GS remained independent predictors of CF. Moreover, in model 2 TV (HR:1.07,) and in model 3 TV >6.29 ml (HR:2.99,) were independently associated with CF. In LOOCV, the C‐index of models 1–3 were 65.53%, 71.75%, and 70.26%, respectively.CONCLUSIONSTV is an independent predictor of CF in hPCa patients. Patients with a TV exceeding the cut‐off of 6.29 ml are more likely to develop CF. Prostate 77:3–9, 2017. © 2016 Wiley Periodicals, Inc.