bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Aus- und Weiterbildungssituation der Abdomensonografie an den deutschen Universitätskliniken. Eine Längsschnittstudie über 20 Jahre
Authors: Welle Reinhard , Seufferlein Thomas , Kratzer Wolfgang 
Published: October 2020

Zusammenfassung
Hintergrund Deutschlandweit ist die sonografische Ausbildung nicht einheitlich geregelt. Ziel der aktuellen Studie ist, eine aktuelle Bestandsaufnahme der Aus- und Weiterbildungssituation der Abdomensonografie an den deutschen Universitätskliniken zu leisten und die Ergebnisse mit den 1999 und 2009 durchgeführten Vorgängerstudien vergleichend auszuwerten.
Methoden Im Rahmen der postalisch durchgeführten Umfragestudie wurden die ärztlichen Leiter der gastroenterologischen Abteilungen der 34 deutschen Universitätskliniken zu den Themenkomplexen technische Ausstattung, Untersuchungszahlen, Rolle der Fachgesellschaften, Ausbildung der Studierenden und Gestaltung der ärztlichen Weiterbildung befragt. Die Rücklaufquote betrug 79 %. An einer ergänzenden Online-Lehrevaluation nahmen 1183 Studierende von 34 Fakultäten teil.
Ergebnisse An den Universitätskliniken findet der abdominelle Ultraschall zunehmend in einem interdisziplinären Rahmen statt; inzwischen sind an 29 % der Kliniken interdisziplinäre Ultraschallzentren etabliert. Eine quantitative Verbesserung der Gerätesituation konnte festgestellt werden, pro Klinik stehen 5,2 Systeme zur Verfügung. Dies entspricht einem Plus von 30 % im Vergleich zu 2009 und 27 % im Vergleich zu 1999. Die Investitionsbereitschaft in moderne Geräte hat hingegen abgenommen. Sowohl die Gesamtuntersuchungszahl als auch die Zahl durchgeführter Kontrastmittelsonografien sind in den vergangenen Jahren stetig gestiegen, zwischen 2009 und 2018 um maximal 28 %. Die DEGUM ist zunehmend an den Kliniken vertreten und hat ihre herausragende Rolle in Qualitätssicherung und Weiterbildung weiter ausgebaut. Inzwischen sind 96 % der ärztlichen Leiter Mitglieder der DEGUM und 89 % verfügen über eine Qualifikation des Mehrstufenkonzepts. Hinsichtlich Ausbildungszeit, abzuleistender Untersuchungen und Ausbildungstagen unter Supervision bestehen weiterhin große Unterschiede zwischen den Abteilungen. Durchschnittlich werden mehr Ärzte pro Abteilung und Jahr ausgebildet und eine kontinuierliche und ganztätige Ausbildungszeit von 6 Monaten hat sich an den meisten Kliniken etabliert. Unter Studierenden genießt die Sonografie hohes Ansehen, und es ist eine enorme Einsatzbereitschaft festzustellen. Die Zahl praktischer Kurse und unterrichteter Studierender hat in den vergangenen Jahren zugenommen. Oft besteht jedoch ein Ungleichgewicht von Angebot und Nachfrage nach Lehrveranstaltungen.
Schlussfolgerung Für das ärztliche Personal und die Studierenden hat sich die Ausbildungssituation tendenziell positiv entwickelt, wobei zwischen den Kliniken weiterhin große Qualitätsunterschiede bestehen. Die Abteilungen leisten eine stetig zunehmende Zahl an Ultraschalluntersuchungen; eine adäquate Verbesserung der Gerätesituation konnte nicht festgestellt werden. Die DEGUM hat ihre Bedeutung als wichtigste den Ultraschall vertretende Fachgesellschaft weiter ausgebaut.
The Effect of Pituitary Gland Disorders on Glucose Metabolism: From Pathophysiology to Management
Authors: Sydney Guy I. , Michalakis Konstantinos , Nikas Ilias P. , Spartalis Eleftherios , Paschou Stavroula A. 
Published: October 2020

AbstractThis review aims to explore, present, and discuss disorders of glucose metabolism implicated in pituitary gland diseases, the appropriate interventions, as well as the therapeutic challenges that may arise. Pituitary pathologies may dysregulate glucose homeostasis, as both the excess and deficiency of various pituitary hormones can affect glucose metabolism. Increased circulating levels of growth hormone, glucocorticoids or prolactin have been shown to mainly provoke hyperglycemic states, while hypopituitarism can be associated with both hyperglycemia and hypoglycemia. Addressing the primary cause of these disorders with the use of surgery, medical treatment or radiotherapy forms the cornerstone of current management strategies. Physicians should bear in mind that some such medications have an unfavorable effect on glucose metabolism too. When unsuccessful, or until the appropriate treatment of the underlying pituitary problem, the addition of established antidiabetic therapies might prove useful. Further studies aiming to discover more accurate and effective drug preparations in combination with optimal lifestyle management models will contribute to achieving a more successful glycemic control in these patients.
Correlation between Primary Myelofibrosis and the Association of Portal Thrombosis with Portal-Biliary Cavernoma: US, MDCT, and MRI Features
Authors: Girolamo Marco Di , Galassi Stefania , Merola Salvatore , Bonome Paolo , Conte Esmeralda , Iannicelli Elsa 
Published: October 2020

Abstract
Objective Myelofibrosis is a rare chronic myelolymphoproliferative disease and is associated with increased risk of venous thromboembolism. The objective of this study is to retrospectively evaluate patients with primary myelofibrosis who underwent abdominal US, MDCT and MRI, in order to identify the development of portal thrombosis and its correlation with portal-biliary cavernoma.
Methods We evaluated 125 patients with initial diagnosis of primary myelofibrosis and nonspecific abdominal pain who had undergone US with color Doppler. In 13 patients (8 men, 5 females; age: 45–85), US detected portal thrombosis with associated portal-biliary cavernoma. All patients subsequently underwent contrast-enhanced MDCT and MRI and 4 patients MR-cholangiography. The correlation between primary myelofibrosis and portal thrombosis and cavernoma respectively was calculated using χ2 test.
Results About 10% of patients with primary myelofibrosis preliminary evaluated with US had partial (8 pts) or complete (5 pts) portal thrombosis associated with portal-biliary cavernoma with a χ2 = 0. In all patients, US detected a concentric thickening of main bile duct (MBD) wall (mean value: 7 mm); color Doppler always showed dilated venous vessels within the thickened wall of the biliary tract. Contrast-enhanced CT and MRI confirmed thickening of MBD walls with their progressive enhancement and allowed better assessment of the extent of the portal system thrombosis. MR-cholangiography showed a thin appearance of the MBD lumen with evidence of ab extrinsic compression.
Conclusions The evidence of portal thrombosis and portal-biliary cavernoma in 10% of the patients with primary myelofibrosis indicates a close correlation between the two diseases. In the detection of portal thrombosis and portal-biliary cavernoma, US with color Doppler is the most reliable and economical diagnostic technique while contrast-enhanced MDCT and MRI allow better assessment of the extent of the portal vein thrombosis and of the complications of myelofibrosis.
Ruptured Pancreaticoduodenal Artery Pseudoaneurysm in an Unusual Location in a Patient with Chronic Pancreatitis: A Case Report
Authors: Wongwaisayawan Sirote , Papadatos Demetri , Aina Rima , Sheikh Adnan 
Published: October 2020

AbstractBleeding pseudoaneurysm is a rare but yet potentially lethal complication in a patient with chronic pancreatitis. It also poses a diagnostic challenge among the radiologists and the attending physicians. The mortality rate can be as high as 50% depending on the clinical status, patient hemodynamics, site, and characteristics of the bleeding pseudoaneurysm. Multidisciplinary team approach is essential to deliver the optimum treatment strategy to each individual patient. In this article, we present a case of chronic pancreatitis that presents with acute epigastric pain caused by ruptured pancreaticoduodenal artery pseudoaneurysm in an unusual location. This patient was successfully treated with transcatheter coil embolization.
Law-abiders, lame ducks, and over-stayers: the Africa Executive Term Limits (AETL) dataset
Authors: Cassani Andrea 
Published: October 2020

AbstractBesides elections, the sub-Saharan wave of political reforms of the 1990s led several countries to introduce limits to the number of terms that a chief executive can serve, even though several leaders managed to bypass them. While Africa’s executive term limits (ETLs) politics has gained scholarly attention, the literature mostly consists of in-depth small-N analyses. Systematic comparative research is rare. To contribute filling this gap, this article presents a new Africa Executive Term Limits (AETL) dataset. Covering 49 sub-Saharan polities throughout the 1990–2019 period, AETL represents the most complete and updated collection of data on Africa’s ETLs politics, and a versatile research tool to address several questions on the present and future of this continent. A preliminary assessment of the new data finds ETLs to be increasingly respected, and to have positive returns for government alternation and development. These findings point to new research avenues that AETL may help travel.
The processing of case in intermediate L2 Spanish
Authors: Jegerski Jill 
Published: October 2020

Abstract
This self-paced reading study investigated the processing of case marking with the particle a in non-native Spanish. Experiment 1 tested online sensitivity to case marking on direct and indirect objects. Unlike native speakers, intermediate L2 learners showed effects only with indirect objects. For Experiment 2, direct objects were doubled with a preverbal clitic, to see if the addition was associated with more native-like processing, as has been shown in previous research with very advanced L2 learners (Jegerski, 2015). Again, online sensitivity to case marking was only observed with the ditransitive stimuli. Thus, clitic doubling only seems to make a difference at sufficiently high levels of proficiency, perhaps because of increasingly robust representations of grammatical forms in the developing L2 system.
Contextual effects in processing OVS constructions in Spanish
Authors: Isabelli Casilde A. 
Published: October 2020

Abstract
This study investigates the contextual constraint principle in input processing, which states that learners may rely less on a first-noun-as-subject/agent strategy if preceding context constrains the interpretation of a clause or sentence. Second language learners of Spanish (N = 39) completed a sentence interpretation task in which they heard OVS sentences in various context conditions: neutral versus constraining context appearing prior to and after OVS clauses. Results revealed greater accuracy on OVS sentence interpretation when constraining context was available, particularly when it appeared prior to the target OVS clause. The results suggest that first noun reliance is significantly weakened when constraining context is available, and that the contextual constraint principle should be expanded to include context in post target-clause position.
Multilevel input processing
Authors: Barcroft Joe 
Published: October 2020

Abstract
Research on input processing (IP) to date has focused largely on sentences and acquisition of morphosyntax. Other research has addressed IP at the lexical level for different aspects of vocabulary acquisition. This chapter clarifies how understanding multilevel IP can improve our understanding of IP across the board. Section 1 defines multilevel IP and clarifies its overarching role when learners are exposed to input. Section 2 summarizes research on sentence-level IP and identifies areas in which research on lexical IP can be informative. Section 3 summarizes research on lexical IP, noting areas in which research on sentence-level IP can be informative. Finally, Section 4 discusses challenges to be met in new efforts to investigate and advance theory related to multilevel IP.
Trials-to-criterion as a methodological option to measure language processing in processing instruction
Authors: Fernández Claudia 
Published: October 2020

Abstract
Trials-to-criterion – a method commonly used in applied behavior analysis as an alternative to the pre-/post-test study design – has been used to observe and assess input processing in processing instruction (PI) research. The results from trials-to-criterion studies have made important contributions to our understanding of the effects of PI in input processing, particularly regarding the role of explicit information. In order to promote trials-to-criterion as a method in PI research, this chapter reviews and discusses studies that have used trials-to-criterion data to investigate the effects of PI on second language processing. It also examines crucial design choices in the implementation of trials-to-criterion as a measure of language processing. Finally, it discusses future considerations for trials-to-criterion research.
PI and the French causative and passive constructions
Authors: Wong Wynne , Ito Kiwako , Glimois Laurene 
Published: October 2020

Abstract
We examined whether French L2 learners trained with processing instruction (PI) or traditional instruction (TI) on the French causative, would transfer training effects to the passive construction. Experiment 2 included explicit information (EI) but not Experiment 1. Accuracy results and eye movement patterns showed PI had a positive impact on participants’ processing of the causative, but neither treatment had any effect on the passive. The null effect could be attributed to the low number of tokens used and to the nature of the passive structure. Furthermore, PI training on the causative might have trained learners to rely on the necessary cues to process causative sentences correctly, but this might not have been sufficient to decrease reliance on the first noun principle.
A new way to classify 2D higher order quantum superintegrable systems
Authors: Berntson Bjorn K , Marquette Ian , Miller Willard 
Published: October 2020

Abstract
We revise a method by Kalnins, Kress and Miller (2010) for constructing a canonical form for symmetry operators of arbitrary order for the Schrödinger eigenvalue equation HΨ ≡ (Δ2 + V)Ψ = EΨ on any 2D Riemannian manifold, real or complex, that admits a separation of variables in some orthogonal coordinate system. We apply the method, as an example, to revisit the Tremblay and Winternitz (2010) derivation of the Painlevé VI potential for a 3rd order superintegrable flat space system that separates in polar coordinates and, as new results, we give a listing of the possible potentials on the two-sphere that separate in spherical coordinates and all two-hyperbolic (two-sheet) potentials separating in horocyclic coordinates. In particular, we show that the Painlevé VI potential also appears for a 3rd order superintegrable system on the two-sphere that separates in spherical coordinates, as well as a 3rd order superintegrable system on the two-hyperboloid that separates in spherical coordinates and one that separates in horocyclic coordinates. Our aim is to develop tools for analysis and classification of higher order superintegrable systems on any 2D Riemannian space, not just Euclidean space.
Model for deformation of cells from external electric fields at or near resonant frequencies
Authors: Martinez Luis , Dhruv Akash , Lin Li , Balaras Elias , Keidar Michael 
Published: October 2020

Abstract
This paper presents a numerical model to investigate the deformation of biological cells by applying external electric fields operating at or near cell resonant frequencies. Cells are represented as pseudo solids with high viscosity suspended in liquid media. The electric field source is an atmospheric plasma jet developed inhouse, for which the emitted energy distribution has been measured. Viscoelastic response is resolved in the entire cell structure by solving a deformation matrix assuming an isotropic material with a prescribed modulus of elasticity. To investigate cell deformation at resonant frequencies, one mode of natural cell oscillation is considered in which the cell membrane is made to radially move about its eigenfrequency. An electromagnetic wave source interacts with the cell and induces oscillation and viscoelastic response. The source carries energy in the form of a distribution function which couples a range of oscillating frequencies with electric field amplitudes. Results show that cell response may be increased by the external electric field operating at or near resonance. In the elastic regime, response increases until a steady threshold value, and the structure moves as a damped oscillator. Generally, this response is a function of both frequency and magnitude of the source, with a maximum effect found at resonance. To understand the full effect of the source energy spectrum, the system is solved by considering five frequency-amplitude couplings. Results show that the total solution is a nonlinear combination of the individual solutions. Additionally, sources with different signal phases are simulated to determine the effect of initial conditions on the evolution of the system, and the result suggests that there may be multiple solutions within the same order of magnitude for elastic response and velocity. Cell rupture from electric stress may occur during application given a high energy source.
Aesthetic Experience and the Unfathomable: A Pragmatist Critique of Hermeneutic Aesthetics
Authors: Gilks Mark 
Published: October 2020

Abstract
In his attack on the notion of immediate experience (Erlebnis), Hans-Georg Gadamer argues that aesthetic experience should be absorbed into hermeneutics because alone it cannot account for the historical nature of experience (Erfahrung); predicated on an ontological theory of art, the unfathomable, therefore, is the sense we have of these infinite hermeneutic depths. I argue that this account is methodologically and existentially unacceptable: methodologically because it is overly speculative, and existentially because it betrays authentic existence. I critique Gadamer from the perspective of William James’ Pragmatism and argue, inverting Gadamer’s main thesis, that hermeneutics should be reduced to aesthetic experience. The meaning that emerges in aesthetic experience does not ‘rise up’ from the depths but is immanent in what James calls ‘pure experience’. The unfathomable, therefore, is not a glimpse into the metaphysical abyss but a phenomenological insight into the immanent structure of experience.
Forest Restoration and Fuels Reduction: Convergent or Divergent?
Authors: Stephens Scott L , Battaglia Mike A , Churchill Derek J , Collins Brandon M , Coppoletta Michelle , Hoffman Chad M , Lydersen Jamie M , North Malcolm P , Parsons Russell A , Ritter Scott M , Stevens Jens T 
Published: October 2020

AbstractFor over 20 years, forest fuel reduction has been the dominant management action in western US forests. These same actions have also been associated with the restoration of highly altered frequent-fire forests. Perhaps the vital element in the compatibility of these treatments is that both need to incorporate the salient characteristics that frequent fire produced—variability in vegetation structure and composition across landscapes and the inability to support large patches of high-severity fire. These characteristics can be achieved with both fire and mechanical treatments. The possible key to convergence of fuel reduction and forest restoration strategies is integrated planning that permits treatment design flexibility and a longer-term focus on fire reintroduction for maintenance. With changing climate conditions, long-term forest conservation will probably need to be focused on keeping tree density low enough (i.e., in the lower range of historic variation) for forest conditions to adapt to emerging disturbance patterns and novel ecological processes.
Atrial nitroso-redox balance and refractoriness following on-pump cardiac surgery: a randomized trial of atorvastatin
Authors: Jayaram Raja , Jones Michael , Reilly Svetlana , Crabtree Mark J , Pal Nikhil , Goodfellow Nicola , Nahar Keshav , Simon Jillian , Carnicer Ricardo , DeSilva Ravi , Ratnatunga Chandana , Petrou Mario , Sayeed Rana , Roalfe Andrea , Channon Keith M , Bashir Yaver , Betts Timothy , Hill Michael , Casadei Barbara 
Published: October 2020

Abstract

Aims
Systemic inflammation and increased activity of atrial NOX2-containing NADPH oxidases have been associated with the new onset of atrial fibrillation (AF) after cardiac surgery. In addition to lowering LDL-cholesterol, statins exert rapid anti-inflammatory and antioxidant effects, the clinical significance of which remains controversial.

Methods and results
We first assessed the impact of cardiac surgery and cardiopulmonary bypass (CPB) on atrial nitroso-redox balance by measuring NO synthase (NOS) and GTP cyclohydrolase-1 (GCH-1) activity, biopterin content, and superoxide production in paired samples of the right atrial appendage obtained before (PRE) and after CPB and reperfusion (POST) in 116 patients. The effect of perioperative treatment with atorvastatin (80 mg once daily) on these parameters, blood biomarkers, and the post-operative atrial effective refractory period (AERP) was then evaluated in a randomized, double-blind, placebo-controlled study in 80 patients undergoing cardiac surgery on CPB. CPB and reperfusion led to a significant increase in atrial superoxide production (74% CI 71–76%, n = 46 paired samples, P &lt; 0.0001) and a reduction in atrial tetrahydrobiopterin (BH4) (34% CI 33–35%, n = 36 paired samples, P &lt; 0.01), and in GCH-1 (56% CI 55–58%, n = 26 paired samples, P &lt; 0.001) and NOS activity (58% CI 52–67%, n = 20 paired samples, P &lt; 0.001). Perioperative atorvastatin treatment prevented the effect of CPB and reperfusion on all parameters but had no significant effect on the postoperative right AERP, troponin release, or NT-proBNP after cardiac surgery.

Conclusion
Perioperative statin therapy prevents post-reperfusion atrial nitroso-redox imbalance in patients undergoing on-pump cardiac surgery but has no significant impact on postoperative atrial refractoriness, perioperative myocardial injury, or markers of postoperative LV function.

Clinical Trial Registration
https://clinicaltrials.gov/ct2/show/NCT01780740
Forecasting using cross-section average–augmented time series regressions
Authors: Karabiyik Hande , Westerlund Joakim 
Published: October 2020

Summary
There is a large and growing body of literature concerned with forecasting time series variables by the use of factor-augmented regression models. The workhorse of this literature is a two-step approach in which the factors are first estimated by applying the principal components method to a large panel of variables, and the forecast regression is then estimated, conditional on the first-step factor estimates. Another stream of research that has attracted much attention is concerned with the use of cross-section averages as common factor estimates in interactive effects panel regression models. The main justification for this second development is the simplicity and good performance of the cross-section averages when compared with estimated principal component factors. In view of this, it is quite surprising that no one has yet considered the use of cross-section averages for forecasting. Indeed, given the purpose to forecast the conditional mean, the use of the cross-sectional average to estimate the factors is only natural. The present paper can be seen as a reaction to this. The purpose is to investigate the asymptotic and small-sample properties of forecasts based on cross-section average–augmented regressions. In contrast to most existing studies, the investigation is carried out while allowing the number of factors to be unknown.