bluuebunny/crossref_metadata_2025_split huggingface dataset:
Flow‐sensitive four‐dimensional cine magnetic resonance imaging for offline blood flow quantification in multiple vessels: A validation study
Authors: Nordmeyer Sarah , Riesenkampff Eugénie , Crelier Gérard , Khasheei Alireza , Schnackenburg Bernhard , Berger Felix , Kuehne Titus 
Published: September 2010

AbstractPurpose:To further validate the quantitative use of flow‐sensitive four‐dimensional velocity encoded cine magnetic resonance imaging (4D VEC MRI) for simultaneously acquired venous and arterial blood flow in healthy volunteers and for abnormal flow in patients with congenital heart disease.Materials and Methods:Stroke volumes (SV) obtained in arterial and venous thoracic vessels were compared between standard two‐dimensional (2D), 4D VEC MRI with and without respiratory navigator gating (gated/nongated) in volunteers (n = 7). In addition, SV and regurgitation fractions (RF) measured in aorta or pulmonary trunk of patients with malformed and/or insufficient valves (n = 10) were compared between 2D and nongated 4D VEC MRI methods.Results:In volunteers and patients, Bland–Altman tests showed excellent agreement between 2D, gated, and nongated 4D VEC MRI obtained quantitative blood flow measurements. The bias between 2D and gated 4D VEC MRI was <0.5 mL for SV; between 2D and nongated 4D VEC MRI the bias was <0.7 mL for SV and <1% for RF.Conclusion:Blood flow can be quantified accurately in arterial, venous, and pathological flow conditions using 4D VEC MRI. Nongated 4D VEC MRI has the potential to be suited for clinical use in patients with congenital heart disease who require flow acquisitions in multiple vessels. J. Magn. Reson. Imaging 2010;32:677–683. © 2010 Wiley‐Liss, Inc.
Manganese transport in the rat optic nerve evaluated with spatial‐ and time‐resolved magnetic resonance imaging
Authors: Olsen Øystein , Kristoffersen Anders , Thuen Marte , Sandvig Axel , Brekken Christian , Haraldseth Olav , Goa Pål Erik 
Published: September 2010

AbstractPurpose:1) To evaluate a novel theoretical model for in vivo axonal Mn2+ transport with MRI data from the rat optic nerve (ON); and 2) to compare predictions from the new model with previously reported experimental data.Materials and Methods:Time‐resolved in vivo T1‐weighted magnetic resonance imaging (MRI) of adult female Sprague–Dawley rat (n = 9) ON was obtained at different timepoints after intravitreal MnCl2 injection. A concentration‐dependent and a rate‐dependent function for the Mn2+ retinal ganglion cell (RGC) axon entrance was convolved with three different transport functions and each model system was optimized to fit the ON data.Results:The rate‐limited input function gave a better fit to the data than the concentration‐limited input. Simulations showed that the rate‐limited input leads to a semilogarithmic relationship between injected dose and Mn2+ concentration in the ON, which is in agreement with previously reported in vivo experiments. A random walk transport model and an anterograde predominant slow model gave a similar fit to the data, both better than an anterograde predominant fast model.Conclusion:The results indicate that Mn2+ input into RGC axons is limited by a maximum entrance rate into the axons. Also, a wide range of apparent Mn2+ transport rates seems to be involved, different from synaptic vesicle transport rates, meaning that manganese does not depict synaptic vesicle transport rates directly. J. Magn. Reson. Imaging 2010;32:551–560. © 2010 Wiley‐Liss, Inc.
Gadoxetic acid‐enhanced MRI versus multiphase multidetector row computed tomography for evaluating the viable tumor of hepatocellular carcinomas treated with image‐guided tumor therapy
Authors: Hwang Jiyoung , Kim Seong Hyun , Kim Young‐Sun , Lee Min Woo , Woo Ji Young , Lee Won Jae , Lim Hyo K. 
Published: September 2010

AbstractPurpose:To compare the diagnostic performance of gadoxetic acid‐enhanced MRI with that of multi‐phase 40‐ or 64‐multidetector row computed tomography (MDCT) to evaluate viable tumors of hepatocellular carcinomas (HCCs) treated with image‐guided tumor therapy.Materials and Methods:A total of 108 patients with 162 HCCs (56 lesions with viable tumor and 106 without viable tumor) treated by means of transcatheter arterial chemoembolization or radiofrequency ablation were retrospectively included in this study. All patients underwent multi‐phase CT at 40‐ or 64‐MDCT and gadoxetic acid‐enhanced MRI using 3.0 Tesla (T). Two observers independently and randomly reviewed the CT and MR images of the treated lesions. The diagnostic performance of two techniques for the evaluation of the viable tumors in the treated lesions was assessed with a receiver operating characteristic (ROC) analysis.Results:For each observer, the areas under the ROC curve were 0.953 and 0.969 for MRI, and 0.870 and 0.888 for MDCT (P < 0.05). The diagnostic accuracies (96.3% for each observer) and sensitivities (92.9% and 96.4%) of MRI in two observers were significantly higher than those (82.7% and 80.9%, 53.6% for each observer, respectively) of MDCT (P < 0.001). The negative predictive values (96.3% and 98.1%) of MRI in two observers were significantly higher than those (80.0% and 79.5%) of MDCT (P < 0.001). For each observer, specificities and positive predictive values did not differ significantly between the two techniques (P > 0.05).Conclusion:Gadoxetic acid‐enhanced MRI shows better diagnostic performance than that of MDCT for evaluating the viable tumors of HCCs treated with image‐guided tumor therapy. J. Magn. Reson. Imaging 2010;32:629–638. © 2010 Wiley‐Liss, Inc.
Effect of the extracranial deep brain stimulation lead on radiofrequency heating at 9.4 Tesla (400.2 MHz)
Authors: Shrivastava Devashish , Abosch Aviva , Hanson Timothy , Tian Jinfeng , Gupte Akshay , Iaizzo Paul A. , Vaughan J. Thomas 
Published: September 2010

AbstractPurpose:To study the effect of the extracranial portion of a deep brain stimulation (DBS) lead on radiofrequency (RF) heating with a transmit and receive 9.4 Tesla head coil.Materials and Methods:The RF heating was studied in four excised porcine heads (mean animal head weight = 5.46 ± 0.14 kg) for each of the following two extracranial DBS lead orientations: one, parallel to the coil axial direction; two, perpendicular to the coil axial direction (i.e., azimuthal). Temperatures were measured using fluoroptic probes at four locations: one, scalp; two, near the second DBS lead electrode‐brain contact; three, near the distal tip of the DBS lead; and four, air surrounding the head. A continuous wave RF power was delivered to each head for 15 min using the coil. Net, delivered RF power was measured at the coil (mean whole head average specific absorption rate = 2.94 ± 0.08 W/kg).Results:RF heating was significantly reduced when the extracranial DBS lead was placed in the axial direction (temperature change = 0–5°C) compared with the azimuthal direction (temperature change = 1–27°C).Conclusion:Development of protocols seems feasible to keep RF heating near DBS electrodes clinically safe during ultra‐high field head imaging. J. Magn. Reson. Imaging 2010;32:600–607. © 2010 Wiley‐Liss, Inc.
Feasibility of FAIR imaging for evaluating tumor perfusion
Authors: Cho Jee‐Hyun , Cho Gyunggoo , Song Youngkyu , Lee Chulhyun , Park Bum‐Woo , Lee Chang Kyung , Kim Namkug , Park Sung Bin , Kang Jong Soon , Kang Moo Rim , Kim Hwan Mook , Kim Young Ro , Cho Kyoung‐Sik , Kim Jeong Kon 
Published: September 2010

AbstractPurpose:To evaluate the feasibility of flow‐sensitive alternating inversion recovery (FAIR) for measuring blood flow in tumor models.Materials and Methods:In eight mice tumor models, FAIR and dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) was performed. The reliability for measuring blood flow on FAIR was evaluated using the coefficient of variation of blood flow on psoas muscle. Three regions of interest (ROIs) were drawn in the peripheral, intermediate, and central portions within each tumor. The location of ROI was the same on FAIR and DCE‐MR images. The correlation between the blood flow on FAIR and perfusion‐related parameters on DCE‐MRI was evaluated using the Pearson correlation coefficient.Results:The coefficient of variation for measuring blood flow was 9.8%. Blood flow on FAIR showed a strong correlation with Kep (r = 0.77), percent relative enhancement (r = 0.73), and percent enhancement ratio (r = 0.81). The mean values of blood flow (mL/100 g/min) (358 vs. 207), Kep (sec−1) (7.46 vs. 1.31), percent relative enhancement (179% vs. 134%), and percent enhancement ratio (42% vs. 26%) were greater in the peripheral portion than in the central portion (P < 0.01).Conclusion:As blood flow measurement on FAIR is reliable and closely related with that on DCE‐MR, FAIR is feasible for measuring tumor blood flow. J. Magn. Reson. Imaging 2010;32:738–744. © 2010 Wiley‐Liss, Inc.
Respiratory motion compensated MR cholangiopancreatography at 3.0 Tesla
Authors: Zho Sang‐Young , Park Jaeseok , Choi Jin‐Young , Kim Dong‐Hyun 
Published: September 2010

AbstractPurpose:To reduce irregular respiratory motion‐induced artifacts in free‐breathing prospective navigator‐triggered three‐dimensional (3D) MR cholangiopancreatography (MRCP).Materials and Methods:A reference respiration model was estimated from the first‐five respiration periods during the initial navigator scan. With the navigator information acquired before and after triggering, the un‐acquired diaphragm position during the actual imaging was interpolated using the amplitude‐scaled reference model. Craniocaudal translational motion during imaging was retrospectively corrected using the estimated diaphragm position. T2‐weighted 3D MRCP data were acquired from 17 healthy volunteers. For quantitative analysis, contrast‐to‐noise ratio (CNR) and relative contrast (RC) of the biliary tree and gallbladder were compared using the paired t‐test.Results:The CNR and RC of the biliary tree and gallbladder were significantly higher (P < 0.05) in the maximum intensity projection images after motion compensation.Conclusion:The proposed algorithm can be an effective tool to reduce the irregular respiratory motion‐induced artifacts in 3D MRCP imaging. J. Magn. Reson. Imaging 2010;32:726–732. © 2010 Wiley‐Liss, Inc.
A note on long‐term variations of the African easterly jet
Authors: Dezfuli Amin K. , Nicholson Sharon E. 
Published: September 2010

AbstractThe African easterly jet (AEJ) is analysed at 600 hPa in August for the period 1948–2003. In most years, the jet reveals strong zonal asymmetries. In many cases a double‐core pattern is evident, such that a western (AEJ/w) and eastern (AEJ/e) component of the jet can be distinguished. The inter‐annual variations of intensity and latitude of the two components demonstrate markedly different behaviour. Intensity and latitude are negatively correlated for the AEJ/e while uncorrelated for AEJ/w. The latitude of the AEJ/w is also relatively invariant, while from year‐to‐year the latitude of the AEJ/e varies by some ten degrees. On inter‐decadal to multi‐decadal timescales, a decrease (increase) in mean intensity of the AEJ/w (AEJ/e) is apparent in the mid‐1970s, coincident with onset of the long dry period in the Sahel. The composite analysis of the wettest and driest 5‐year periods suggests that in the wet years the dominant core is the western one, while the eastern one is dominant in the dry years. Our explanation for the existence of the two cores and their disparate behaviour involves an inertial instability mechanism that controls the lower and mid‐tropospheric winds in the eastern portion of the AEJ (i.e. in the central and eastern Sahel). Copyright © 2010 Royal Meteorological Society
Assessing trends in extreme precipitation events intensity and magnitude using non‐stationary peaks‐over‐threshold analysis: a case study in northeast Spain from 1930 to 2006
Authors: Beguería Santiago , Angulo‐Martínez Marta , Vicente‐Serrano Sergio M. , López‐Moreno J. Ignacio , El‐Kenawy Ahmed 
Published: September 2010

AbstractMost applications of the extreme value (EV) theory have assumed stationarity, i.e. the statistical properties of the process do not change over time. However, there is evidence suggesting that the occurrence of extreme events is not stationary but changes naturally, as it has been found for many other climate variables. Of paramount importance for hazard analysis is whether the observed precipitation time series exhibit long‐term trends or cycles; such information is also relevant in climate change studies. In this study, the theory of non‐stationary extreme value (NSEV) analysis was applied to data series of daily precipitation using the peaks‐over‐threshold (POT) approach. A Poisson/generalized Pareto (P/GP) model, in which the model parameters were allowed to vary linearly with time, was fitted to the resulting series of precipitation event's intensity and magnitude. A log‐likelihood ratio test was applied to determine the existence of trends in the model parameters. The method was applied to a case study in northeast Spain, comprising a set of 64 daily rainfall series from 1930 to 2006. Statistical significance was achieved in less than 5% of the stations using a linear non‐stationary model at the annual scale, indicating that there is no evidence of a generalized trend in extreme precipitation in the study area. At the seasonal scale, however, a significant number of stations along the Mediterranean (Catalonia region) showed a significant decrease of extreme rainfall intensity in winter, while experiencing an increase in spring. Copyright © 2010 Royal Meteorological Society
Approaches to quantify progressive soil development with time in Mediterranean climate—I. Use of field criteria
Authors: Sauer Daniela 
Published: September 2010

AbstractSoil‐chronosequence studies are useful to assess relationships between land‐surface ages and stages of soil formation. Such relationships may then be applied to establish relative chronologies of development of land surfaces of unknown ages, contributing to landscape‐history reconstruction. For this purpose, it is important to identify those soil properties that are most closely related to soil age. This article reviews soil‐chronosequence studies from Mediterranean regions in Europe and California. Soil properties described in the field and soil‐development indices based on field criteria that have been used in the studies are evaluated. The properties total texture, rubification, clay films, dry consistence, and soil thickness are identified as useful and easy‐to‐obtain soil parameters, which are generally closely related to soil age. Most soil properties exhibit their greatest changes during certain phases of soil development, e.g., soil structure in soils < 10,000 y and rubification in soils > 100,000 y. The specific time spans of major changes of soil properties need to be considered, when looking for appropriate parameters to study a particular chronosequence. Indices, which combine several soil properties having their greatest changes in different phases of soil development, are useful to study soil chronosequences comprising large time spans, e.g., from Holocene to Middle Pleistocene. It is important to be aware that soil chronofunctions obtained from Pleistocene soils integrate rates of soil‐forming processes over periods of very variable climate and environment, and that soil development crossed internal and external pedogenic thresholds that are not reflected in soil chronofunctions.
Endoscopic modified lothrop procedure: A radiographic anatomic study
Authors: Burkart Collin M. , Zimmer Lee A. 
Published: September 2010

AbstractObjective:Radiographic frontal recess and sinus anatomic measurements were obtained to evaluate the feasibility of the endoscopic modified Lothrop procedure.Study Design:Computed tomography anatomic study.Materials and Methods:Computed tomography (CT) scans from 97 patients, 39 male and 58 female, were analyzed in the sagittal plane. Four anatomic parameters were measured 1) midsagittal thickness of the nasal beak, 2) midsagittal distance from nasal beak to skull base, 3) accessible dimension of the frontal recess, and 4) anterior to posterior (AP) dimension of the frontal sinus.Results:The average and range of each parameter are as follows: 1) midsagittal nasal beak thickness 0.8 cm (0.3–1.4 cm); 2) midsagittal beak to skull base 1.0 cm (0.4–2.4 cm); 3) left and right accessible dimension 0.8 cm (0.3–1.4 cm) and 0.8 cm (0.4–1.5 cm), respectively; 4) left and right AP diameter of the frontal sinus 1.0 cm (0.3–1.8 cm) and 1.1 cm (0.4–1.9 cm), respectively. There is statistically significant differences between the accessible dimension and AP dimension of the frontal sinus on male and female images.Discussion:Preoperative frontal recess and sinus measurements can aid in the selection of patients for the endoscopic modified Lothrop procedure. A significant portion of the population, especially women, had limiting anatomic factors potentially excluding this procedure. Laryngoscope, 2010
Disappearance of essential tremor after stroke
Authors: Dupuis Michel J.‐M. , Evrard Frédéric L.A. , Jacquerye Philippe G. , Picard Gaëtane R. , Lermen Oliver G. 
Published: September 2010

AbstractImprovement of a patient's essential tremor (ET) after a stroke has rarely been reported. In such patients, cerebral imaging could help to identify structures involved in the maintenance of ET and improves the knowledge of its physiopathology. This article reports the disappearance of ET, after a stroke in 4 patients and reviews similar previously published cases. These cases suggest that the interruption of cerebellar loops during a stroke could be responsible for the disappearance of ET. © 2010 Movement Disorder Society
Short‐term attention and verbal fluency is decreased in restless legs syndrome patients
Authors: Fulda Stephany , Beitinger Marie E. , Reppermund Simone , Winkelmann Juliane , Wetter Thomas C. 
Published: September 2010

AbstractRestless legs syndrome (RLS) is a frequent sleep‐related movement disorder with disturbed sleep and quality of life. RLS patients complain about increased daytime sleepiness, but there are only few and inconsistent reports about cognitive functioning in this group. We compared cognitive performance of 23 unmedicated RLS patients to that of 23 healthy controls matched individually for age, gender, and educational level. Cognitive tasks were chosen to assess short‐term attention, working memory, learning and memory, verbal fluency, and executive functioning. RLS patients performed worse than controls in the area of attention and verbal fluency, and performance in these tasks was associated with RLS severity, sleep quality, depression scores, and memory. There was no difference for working memory, memory, learning, cognitive flexibility, and abstract reasoning. We conclude that there is evidence for deficits in short‐term attention and verbal fluency in RLS patients. © 2010 Movement Disorder Society.
A scalable, efficient and informative approach for anomaly‐based intrusion detection systems: theory and practice
Authors: Salem Osman , Vaton Sandrine , Gravey Annie 
Published: September 2010

AbstractIn this paper, we present the design and implementation of a new approach for anomaly detection and classification over high speed networks. The proposed approach is based first of all on a data reduction phase through flow sampling by focusing mainly on short lived flows. The second step is then a random aggregation of some descriptors such as a number of SYN packets per flow in two different data structures called Count Min Sketch and Multi‐Layer Reversible Sketch. A sequential change point detection algorithm continuously monitors the sketch cell values. An alarm is raised if a significant change is identified in cell values. With an appropriate definition of the combination of IP header fields that should be used to identify one flow, we are able not only to detect the anomaly but also to classify the anomaly as DoS, DDoS or flash crowd, network scanning and port scanning. We validate our framework for anomaly detection on various real world traffic traces and demonstrate the accuracy of our approach on these real‐life case studies. Our analysis results from online implementation of our algorithm over measurements gathered by a DAG sniffing card are very attractive in terms of accuracy and response time. The proposed approach is very effective in detecting and classifying anomalies, and in providing information by extracting the culprit flows with a high level of accuracy. Copyright © 2010 John Wiley & Sons, Ltd.
An evaluation of automatic parameter tuning of a statistics‐based anomaly detection algorithm
Authors: Himura Yosuke , Fukuda Kensuke , Cho Kenjiro , Esaki Hiroshi 
Published: September 2010

AbstractWe investigate an automatic and dynamic parameter tuning of a statistical method for detecting anomalies in network traffic (this tuning is referred to as parameter learning) towards real‐time detection. The main idea behind the dynamic tuning is to predict an appropriate parameter for upcoming traffic by considering the detection results of past τ traces of traffic. The τ is referred to as the learning period, and we discuss in particular the appropriate value of τ. This automatic tuning scheme is applied to parameter setting of an anomaly detection method based on Sketch and the multi‐scale gamma model, which is an unsupervised method and does not need predefined data. We analyze the tuning scheme with real traffic traces measured on a trans‐Pacific link over 9 years (15 min from 14:00 Japan Standard Time every day, and 24 consecutive hours for some dates on the same link). The detection results with parameter prediction are compared to those with ideal parameters that maximize the detection performance for upcoming traffic. We also analyze predictability of the ideal parameter considering the past changes in it. The main findings of this work are as follows: (1) the ideal parameter fluctuates day by day; (2) parameter learning with a longer τ is affected by significant events included in the period, and the appropriate τ is about three traces (days) for everyday 15 min traces and around 1.5 h for 24 h traces; (3) the degradation in detection performance caused by introducing parameter learning is 17% with τ = 3 for everyday 15 min traces; (4) the changes in the ideal parameter have no periodic correlation, and can be modeled as a random process followed by a normal distribution. We show that one cannot consistently use a fixed parameter in statistics‐based algorithms to detect anomalies in practice. Copyright © 2010 John Wiley & Sons, Ltd.
Nitrate und PDE5‐Hemmer: Pharmazeutische Betreuung. Therapiebegleitende Beratung in der Apotheke
Authors: Ude Miriam , Ude Christian , Leuner Kristina 
Published: September 2010

AbstractNitrate werden vor allem eingesetzt, um akute Angina‐pectoris‐Anfälle zu therapieren. Patienten, die zu Beginn der Therapie unter Nitrat‐Kopfschmerz leiden, sollten motiviert werden, die Therapie fortzuführen und compliant zu sein. Da Nitrate in vielen verschiedenen, auch erklärungsbedürftigen Darreichungsformen auf dem Markt sind, die im Notfall sofort einsetzbar sein müssen, ist es im Rahmen der pharmazeutischen Betreuung wichtig, die Patienten zu informieren und im Umgang mit der Arznei zu schulen. Eine fundierte pharmazeutische Beratung im Zusammenhang mit der Abgabe von PDE5‐Hemmern stellt an das Apothekenpersonal hohe Ansprüche. Dies ist weniger die Folge aufgrund besonderer galenischer Darreichungsformen oder pharmakodynamischer Besonderheiten der Wirkstoffe; vielmehr muss mit Diskretion und dem richtigen Umgang mit dem Patienten die optimale Beratungsatmosphäre geschaffen werden.
XF‐73 – eine neue antibakterielle Leitstruktur
Authors: Schmitz Jens , Holzgrabe Ulrike 
Published: September 2010

AbstractDie Zahl der neuen Antibiotika, die jährlich auf den Markt kommen, sinkt stetig. Außerdem sind in den letzten Jahren nur sehr wenige Antibiotika mit neuem Wirkmechanismus zugelassen worden. Ausnahmen bilden Linezolid (1999) oder Daptomycin (2007). Zusätzlich nimmt das Ausmaß der Resistenzentwicklung gegenüber den verfügbaren Antibiotika erschreckend zu.