bluuebunny/crossref_metadata_2025_split huggingface dataset:
Technical Note: Noise models for virtual clinical trials of digital breast tomosynthesis
Authors: Borges Lucas R. , Barufaldi Bruno , Caron Renato F. , Bakic Predrag R. , Foi Alessandro , Maidment Andrew D. A. , Vieira Marcelo A. C. 
Published: April 2019

PurposeTo investigate the use of an affine‐variance noise model, with correlated quantum noise and spatially dependent quantum gain, for the simulation of noise in virtual clinical trials (VCT) of digital breast tomosynthesis (DBT).MethodsTwo distinct technologies were considered: an amorphous‐selenium (a‐Se) detector with direct conversion and a thallium‐doped cesium iodide (CsI(Tl)) detector with indirect conversion. A VCT framework was used to generate noise‐free projections of a uniform three‐dimensional simulated phantom, whose geometry and absorption match those of a polymethyl methacrylate (PMMA) uniform physical phantom. The noise model was then used to generate noisy observations from the simulated noise‐free data, while two clinically available DBT units were used to acquire projections of the PMMA physical phantom. Real and simulated projections were then compared using the signal‐to‐noise ratio (SNR) and normalized noise power spectrum (NNPS).ResultsSimulated images reported errors smaller than 4.4% and 7.0% in terms of SNR and NNPS, respectively. These errors are within the expected variation between two clinical units of the same model. The errors increase to 65.8% if uncorrelated models are adopted for the simulation of systems featuring indirect detection. The assumption of spatially independent quantum gain generates errors of 11.2%.ConclusionsThe investigated noise model can be used to accurately reproduce the noise found in clinical DBT. The assumption of uncorrelated noise may be adopted if the system features a direct detector with minimal pixel crosstalk.
GPR measurements to identify cracks and textural arrangements in the altar wall of the 16th‐century Santa Maria Huiramangaro Church, Michoacán, Mexico
Authors: Ortega‐Ramírez J. , Bano M. , de Larrea‐López L. Lelo , Robles‐Camacho J. , Ávila‐Luna P. , Villa‐Alvarado L.A. 
Published: April 2019

ABSTRACTA three‐dimensional ground‐penetrating radar survey was performed on the altar wall, which faced the risk of collapse, of a 16th‐century church in Michoacán, Mexico. The ground‐penetrating radar survey with high‐frequency antennas aimed to locate structural cracks and texture arrangements, the latter through the interpretation of the patterns in the electromagnetic data. The results indicate that the superficially visible cracks or fractures, except for the lateral ones at each end of the wall, disappear at a depth of between 15 and 25 cm. The lower part of the wall below a height of 3.97 m presents an area with multiple diffractions, which suggests that the masonry is made of ‘stone and mud’ and the tilt appears precisely where the adobe wall starts. Using 1500 and 900 MHz antennas, the identified texture of the wall shows at least three leaves or layers with diverse materials and a wooden beam embedded in the wall. Additionally, the survey near the church with a 200 MHz antenna supports the hypotheses that local construction materials were used here. The results inspire us to continue applying ground‐penetrating radar, a non‐destructive method, to diagnose the walls and structures of historical monuments before any intervention.
MAPK pathway activity plays a key role in PD‐L1 expression of lung adenocarcinoma cells
Authors: Stutvoet Thijs S , Kol Arjan , de Vries Elisabeth GE , de Bruyn Marco , Fehrmann Rudolf SN , Terwisscha van Scheltinga Anton GT , de Jong Steven 
Published: April 2019

AbstractImmune checkpoint inhibitors targeting programmed cell death protein 1 (PD‐1) and programmed death‐ligand 1 (PD‐L1) have improved the survival of patients with non‐small cell lung cancer (NSCLC). Still, many patients do not respond to these inhibitors. PD‐L1 (CD274) expression, one of the factors that influences the efficacy of immune checkpoint inhibitors, is dynamic. Here, we studied the regulation of PD‐L1 expression in NSCLC without targetable genetic alterations in EGFR, ALK, BRAF, ROS1, MET, ERBB2 and RET. Analysis of RNA sequencing data from these NSCLCs revealed that inferred IFNγ, EGFR and MAPK signaling correlated with CD274 gene expression in lung adenocarcinoma. In a representative lung adenocarcinoma cell line panel, stimulation with EGF or IFNγ increased CD274 mRNA and PD‐L1 protein and membrane levels, which were further enhanced by combining EGF and IFNγ. Similarly, tumor cell PD‐L1 membrane levels increased after coculture with activated peripheral blood mononuclear cells. Inhibition of the MAPK pathway, using EGFR inhibitors cetuximab and erlotinib or the MEK 1 and 2 inhibitor selumetinib, prevented EGF‐ and IFNγ‐induced CD274 mRNA and PD‐L1 protein and membrane upregulation, but had no effect on IFNγ‐induced MHC‐I upregulation. Interestingly, although IFNγ increases transcriptional activity of CD274, MAPK signaling also increased stabilization of CD274 mRNA. In conclusion, MAPK pathway activity plays a key role in EGF‐ and IFNγ‐induced PD‐L1 expression in lung adenocarcinoma without targetable genetic alterations and may present a target to improve the efficacy of immunotherapy. © 2019 The Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Seroepidemiological analysis and literature review of the prevalence of Epstein‐Barr virus and herpesvirus infections in pediatric cases with non‐Hodgkin lymphoma in Central Europe
Authors: Vaillant Vera , Reiter Alfred , Zimmermann Martin , Wagner Hans‐Joachim 
Published: April 2019

AbstractBackgroundEpstein‐Barr virus (EBV) is linked to a variety of malignancies; most endemic Burkitt lymphoma (BL) harbor EBV, whereas only a subset of the cases of sporadic BL is EBV positive.ProcedureWe retrospectively determined the herpesvirus seroprevalence at the time of diagnosis in pediatric non‐Hodgkin lymphoma (NHL) patients enrolled in NHL‐BFM (Berlin‐Frankfurt‐Muenster) studies. We accessed the seroepidemiological data from 1147 patients that became available during 1990‐2007. We included the records from patients 6 months to 18 years of age with BL, T‐cell lymphoblastic lymphoma (T‐LBL), lymphoblastic precursor B‐cell lymphoma (pB‐LBL), diffuse large B‐cell lymphoma (DLBCL), or anaplastic large cell lymphoma (ALCL).ResultsEBV seropositivity was significantly more frequent in patients with BL than in those with T‐LBL. EBV was more prevalent in patients younger than 6 years of age and in patients with BL than in those with non‐BL or T‐LBL. Event‐free survival was significantly lower in varicella‐zoster–seronegative patients, but there was no indication of an association to complications due to varicella zoster infection. We found no associations between herpes simplex virus, varicella zoster virus, or human cytomegalovirus seroprevalence and the pediatric Central European NHL cases.ConclusionEarly EBV exposure may increase the risk of BL in Central Europe. A higher involvement of EBV in European BL than originally reported appears at least probable. Our data support the thesis that the distinction between endemic and sporadic BL is artificial and should be replaced by the differentiation between EBV‐positive and EBV‐negative BL.
Modelling of Al/MnO2 and Ti/MnO2 Thermite Mixtures
Authors: Knapp Sebastian , Eisenreich Norbert , Kelzenberg Stefan , Roth Evelin , Weiser Volker 
Published: April 2019

AbstractIn previous work a model was developed and introduced to describe the conversion of pyrotechnic mixtures taking in consideration its particulate character and solving the heat and the mass transfer coupled with reaction kinetics [1]. In this work the model was applied to thermite mixtures with manganese(IV) oxide as oxidizer and aluminium or titanium as fuel. The modelling results of burning rate dependent of fuel‐oxidizer ratio were compared with results from experiments. For the modelling process, the educts were characterized by determining particle size and distribution and chemical reaction kinetics parameters. Other parameters were taken from literature. The modelling results are in good agreement with the experimental ones. It seems that the made physical and chemical assumptions are the main factors to describe the shape of burning rate profile in thermite combustion and the negligence are not influential.
Haptic feedback in the da Vinci Research Kit (dVRK): A user study based on grasping, palpation, and incision tasks
Authors: Saracino Arianna , Deguet Anton , Staderini Fabio , Boushaki Mohamed Nassim , Cianchi Fabio , Menciassi Arianna , Sinibaldi Edoardo 
Published: April 2019

AbstractBackgroundIt was suggested that the lack of haptic feedback, formerly considered a limitation for the da Vinci robotic system, does not affect robotic surgeons because of training and compensation based on visual feedback. However, conclusive studies are still missing, and the interest in force reflection is rising again.MethodsWe integrated a seven‐DoF master into the da Vinci Research Kit. We designed tissue grasping, palpation, and incision tasks with robotic surgeons, to be performed by three groups of users (expert surgeons, medical residents, and nonsurgeons, five users/group), either with or without haptic feedback. Task‐specific quantitative metrics and a questionnaire were used for assessment.ResultsForce reflection made a statistically significant difference for both palpation (improved inclusion detection rate) and incision (decreased tissue damage).ConclusionsHaptic feedback can improve key surgical outcomes for tasks requiring a pronounced cognitive burden for the surgeon, to be possibly negotiated with longer completion times.
Impulsive control of continuous‐time homogeneous positive delay systems of degree one
Authors: Yang Huitao , Zhang Yu 
Published: April 2019

SummaryThis paper investigates the impulsive control of continuous‐time homogeneous positive delay systems of degree one. By using max‐separable Lyapunov functions and Razumikhin technique, a number of stability criteria for continuous‐time homogeneous impulsive positive delay systems of degree one are obtained. It should be noted that it is the first time that impulsive stabilization results for the addressed systems are given. Three numerical examples are presented to demonstrate the effectiveness of the control strategy.
Teaching Sourcing in Upper Secondary School: A Comprehensive Sourcing Intervention With Follow‐Up Data
Authors: Bråten Ivar , Brante Eva W. , Strømsø Helge I. 
Published: April 2019

AbstractIn this quasi‐experimental study, the authors examined the effects of an intervention designed to teach upper secondary school students to take source information, such as author expertise, into consideration when selecting, processing, and using textual resources to complete particular multiple‐document literacy tasks. The intervention centered on a contrasting cases approach framed by authentic curriculum‐based classroom activities and was implemented over six weeks by teachers who had participated in professional development seminars. The findings demonstrated that students who had participated in the sourcing intervention placed more value on source information when selecting texts, invested more time and effort in processing the texts they selected, and more frequently attributed textual ideas to their respective sources compared with students who had participated in typical classroom activities instead. These effects were observed on far transfer tasks in which students worked with multiple documents on different topics in different situational contexts for different purposes, and were sustained over a period of 5.5 weeks. The discussion highlights the uniqueness of the current intervention work and centers on the aspects of the sourcing intervention that likely promoted these broad, sustainable, and transferable sourcing skills in students. Attention is also directed to several possible lines of future research in this area.
Sex differences in executive functioning and latent herpesvirus reactivation among bereaved and nonbereaved individuals
Authors: Guevara Jasmin E. , Gilbert Sarah , Murdock Kyle W. , Stowe Raymond P. , Fagundes Christopher P. 
Published: April 2019

AbstractThe death of a spouse is a highly stressful event. Better executive functioning has been shown to benefit men to a greater degree than women during stress. We evaluated potential sex differences in stress and immune dysregulation among control and bereaved participants who completed a self‐report measure of perceived stress, neuropsychological measures of inhibition and updating/monitoring of information in working memory, and a blood draw to measure Epstein–Barr virus (EBV) antibody titres. Moderation analyses were conducted to test the hypothesis that better inhibition would be associated with less stress and immune dysregulation among male bereaved participants compared with female bereaved participants. Bereaved females demonstrated greater EBV antibody titres than bereaved males. Male bereaved participants benefited from better inhibition, as evidenced by fewer EBV antibody titres, whereas bereaved female participants did not. In the control group, males with high inhibition reported lower stress than males with low inhibition. Present study results are an important step towards identifying those at greatest risk of stress and poor health.
Prior ties and the limits of peer effects on startup team performance
Authors: Hasan Sharique , Koning Rembrand 
Published: April 2019

Research SummaryWe conduct a field experiment at an entrepreneurship bootcamp to investigate whether interaction with proximate peers shapes a nascent startup team's performance. We find that teams whose members lack prior ties to others at the bootcamp experience peer effects that influence the quality of their product prototypes. A 1‐SD increase in the performance of proximate teams is related to a two‐thirds SD improvement for a focal team. In contrast, we find that teams whose members have many prior ties interact less frequently with proximate peers, and thus their performance is unaffected by nearby teams. Our findings highlight how prior social connections, which are often a source of knowledge and influence, can limit new interactions and thus the ability of organizations to leverage peer effects to improve the performance of their members.
Managerial SummaryResearchers and policymakers believe that accelerators, incubators, and bootcamps help entrepreneurial ecosystems spur innovation and drive startup growth. The effectiveness of these organizations, in large part, depends on the new social interactions fostered among colocated entrepreneurs. Yet, little evidence exists about the extent to which such interactions actually lead to spillovers. We ran a controlled experiment at a startup bootcamp to investigate when entrepreneurs were most affected by their colocated peers. Not everyone benefited. We found that entrepreneurs with many prior ties to others at the bootcamp made fewer new connections, especially to neighboring peers, and thus did not experience significant spillovers. In contrast, those without prior connections experienced the greatest spillovers because they interacted frequently with people on nearby colocated teams. Our findings highlight how organizations like incubators and bootcamps, designed to foster new connections, might sometimes just reinforce old networks.
Zum Tragverhalten und zur Bemessung von Schrauben unter kombinierter Zug‐Abscher‐Belastung
Authors: Renner Anja , Lange Jörg 
Published: April 2019

AbstractHerrn Univ.‐Prof. Dr.‐Ing. habil. Frank Werner zur Vollendung seines 70. Lebensjahres gewidmetDas Tragverhalten von stahlbautypischen Schrauben, die einer Interaktionsbelastung, also einer kombinierten Belastung aus Zug‐ und Abscherkraft, ausgesetzt sind, wurde am Institut für Stahlbau und Werkstoffmechanik der TU Darmstadt grundlegend untersucht. Auslöser war, dass die Neuauswertung der bestehenden Versuchsreihen zu diesem Thema für die Erstellung des Eurocodes 3 gezeigt hatte, dass die bis zu diesem Datum als valid angesehene quadratische Interaktionsbedingung zum Nachweis kombiniert belasteter Schrauben nicht auf der sicheren Seite liegt. Dies führte zur Änderung der Nachweisformel im Eurocode 3.Eine genauere Betrachtung der Datenlage zeigt, dass die Anzahl der bisher durchgeführten Versuche überraschend gering ist. Durch das Fehlen wichtiger Bezugswerte wie der Festigkeiten der getesteten Schrauben sind die Daten auch nur bedingt auswertbar. Eine grundlegende Betrachtung, wie sich kombiniert belastete Schrauben verhalten, fehlte gänzlich.Aus diesem Grund wurden im Rahmen eines Forschungsvorhabens die bestehenden Studien neu und zusammenfassend ausgewertet, neue Versuche durchgeführt, diese mithilfe der Methode der finiten Elemente nachgebildet und das Tragverhalten so erstmals grundlegend analysiert. Anhand von Parameterstudien konnte die Übertragbarkeit der Ergebnisse überprüft werden. Im vorliegenden Beitrag werden die Erkenntnisse zusammengefasst und die Möglichkeiten für eine zukünftige Handhabung des Interaktionsnachweises für Schrauben diskutiert.
Grundlagen der sicherheitsäquivalenten Bewertung von Brücken mit Bauwerksmonitoring
Authors: Geißler Karsten , Steffens Nico , Stein Ronald 
Published: April 2019

AbstractHerrn Univ.‐Prof. Dr.‐Ing. habil. Frank Werner zur Vollendung seines 70. Lebensjahres gewidmetDer Zustand und das Alter vieler Brücken in Deutschland einerseits und die zunehmend steigenden Verkehrslasten andererseits erfordern erweiterte Methoden zur Bewertung der Bauwerke, da nicht alle Brücken zeitnah verstärkt oder erneuert werden können. Zur möglichst realitätsnahen Einschätzung des Tragwerks im Grenzzustand der Tragfähigkeit sowie auch hinsichtlich der Ermüdungssicherheit kann deshalb ein unterstützendes Bauwerksmonitoring sehr wichtig sein.Der Begriff Bauwerksmonitoring beinhaltet ausgehend von einer klaren Zielstellung und dem entsprechenden Messkonzept die Dauermessungen zum Bauteil‐ bzw. Tragwerksverhalten über einen festgelegten Zeitraum und die anschließende Datenauswertung. Bei der Erarbeitung der Zielstellung einschließlich des Messkonzepts sowie der Datenauswertung durch zielorientierte Datenreduktionsmethoden ist der mit dem Tragwerk vertraute Ingenieur unabdingbar.Für die Bauwerksbewertung ist es wesentlich, wie die messtechnisch ermittelten Ergebnisse in den Kontext des Sicherheitskonzepts zur Nachrechnung einzuordnen sind. In dem Beitrag werden die Grundlagen dieser messwertgestützten Bewertung und deren anwendungsorientierte Umsetzung durch gegebenenfalls modifizierte (objektbezogene) Lastmodelle und zugehörige Sicherheitselemente vorgestellt.
Corporate governance and accounting conservatism in Islamic banks
Authors: Almutairi Ali R. , Quttainah Majdi A. 
Published: April 2019

AbstractWe examine whether Islamic banks are more likely to be conservative in their financial reporting than conventional banks, as well as how Islamic banks' unique corporate governance system affects accounting conservatism behaviors. Using a large sample of Islamic banks and their matched non‐Islamic banks; based on total assets and geographic location, in 15 countries, we find Islamic banks are more likely to deploy accounting conservatism as measured by loss avoidance, abnormal loan loss provisions, and C‐score, respectively. Islamic banks are about 95% more likely to be more conservative in accounting practices than their counterparts, depending on different model specifications. In addition, we report several board characteristics, such as size, independence, reputation, tenure, and diversity, are important determinants of accounting conservatism in Islamic banks. This relationship indicates certain board traits lead to greater monitoring roles, consequently reducing unethical behavior and increasing the degree of conservatism in accounting practices.
Crash sign: new first‐trimester sonographic marker of spina bifida
Authors: Ushakov F. , Sacco A. , Andreeva E. , Tudorache S. , Everett T. , David A. L. , Pandya P. P. 
Published: April 2019

ABSTRACTObjectivesTo describe a new first‐trimester sonographic sign, the ‘crash sign’, associated with fetal open spina bifida, and to evaluate its clinical usefulness in the first‐trimester diagnosis of spina bifida.MethodsThis was a retrospective review of patients referred to three fetal medicine centers in the first trimester (11 + 0 to 13 + 6 weeks) with suspected spina bifida. Spina bifida was confirmed by direct visualization of the spinal defect on ultrasound by two experts and, when possible, by fetal postmortem examination. Ultrasound images were reviewed for the presence of the crash sign, which is the posterior displacement of the mesencephalon and deformation against the occipital bone in the axial view. The first‐trimester ultrasound images of a mixed group of 10 cases and 40 control fetuses without spina bifida were assessed for the presence of the crash sign by two assessors blinded to the diagnosis.ResultsThe crash sign was present in 48 out of 53 confirmed cases of spina bifida. Of these, 27 had isolated spina bifida and 21 had an associated anomaly. Of the five cases without the crash sign, one had isolated spina bifida and four had an associated anomaly. The crash sign was not reported in any of the control fetuses.ConclusionsWe have described a new first‐trimester sonographic marker for the diagnosis of spina bifida. Our results suggest that the crash sign may be a useful tool in the first‐trimester detection of spina bifida. Prospective evaluation of the crash sign would be beneficial, ideally in a routine clinical screening ultrasound setting. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
First‐trimester screening for trisomies by cfDNA testing of maternal blood in singleton and twin pregnancies: factors affecting test failure
Authors: Galeva S. , Gil M. M. , Konstantinidou L. , Akolekar R. , Nicolaides K. H. 
Published: April 2019

ABSTRACTObjectiveTo examine factors affecting the rate of failure to obtain a result from cell‐free DNA (cfDNA) testing of maternal blood for fetal trisomies 21, 18 and 13 in singleton and twin pregnancies in the first trimester.MethodsThis was a prospective study of 23 495 singleton and 928 twin pregnancies undergoing screening for fetal trisomy by targeted cfDNA testing at 10 + 0 to 14 + 1 weeks' gestation. Multivariate logistic regression analysis was used to determine significant predictors of failure to obtain a result after first sampling.ResultsThere was no result from cfDNA testing after first sampling in 3.4% (798/23 495) of singletons, 11.3% (91/806) of dichorionic twins and 4.9% (6/122) of monochorionic twins. Multivariate logistic regression analysis demonstrated that the risk of test failure, first, increased with increasing maternal age (odds ratio (OR), 1.02; 95% CI, 1.01–1.04) and weight (OR, 1.05; 95% CI, 1.04–1.05), decreasing gestational age (OR, 0.85; 95% CI, 0.79–0.91), serum pregnancy‐associated plasma protein‐A (PAPP‐A) multiples of the median (MoM) (OR, 0.56; 95% CI, 0.49–0.65) and free β‐human chorionic gonadotropin (β‐hCG) MoM (OR, 0.67; 95% CI, 0.60–0.74), second, was higher in women of black (OR, 1.72; 95% CI, 1.33–2.20) and South Asian (OR, 1.99; 95% CI, 1.56–2.52) than those of white racial origin, in dichorionic twin than in singleton pregnancy (OR, 1.75; 95% CI, 1.34–2.26) and in pregnancies conceived by in‐vitro fertilization than in those conceived naturally (OR, 3.82; 95% CI, 3.19–4.55) and, third, was lower in parous than in nulliparous women (OR, 0.63; 95% CI, 0.55–0.74).ConclusionsMaternal age, weight, racial origin and parity, gestational age, dichorionicity, method of conception and serum levels of free β‐hCG and PAPP‐A are independent predictors of cfDNA test failure. The risk of test failure is higher in dichorionic twin than in singleton pregnancies, mainly because a higher proportion of twins are conceived by in‐vitro fertilization and more of the women are nulliparous. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.