bluuebunny/crossref_metadata_2025_split huggingface dataset:
On optimal anchor placement for area‐based localisation in wireless sensor networks
Authors: Cheriet Abdelhakim , Bachir Abdelmalik , Lasla Noureddine , Abdallah Mohamed 
Published: February 2021

AbstractWe consider the problem of optimal anchor placement for area‐based localisation algorithms with the goal of providing cost‐effective, simple, and robust positioning in wireless sensor networks. Due to the high complexity of the problem, we propose two placement algorithms based on heuristics. The first, called genetic algorithm anchors placement (GAAP), is based on genetic algorithms meta‐heuristic, and the second, called local search anchors placement (LSAP), is based on an intuitive heuristic inspired from search techniques used in quad‐trees. For the evaluation of these algorithms, we built a simulation framework, which we made publicly available for the community, and compared their performance against a Brute force (BF) algorithm, and against RND, a random walk‐inspired algorithm. Obtained results show that GAAP provides anchor placements that lead to a very high accuracy while keeping execution time drastically smaller compared to LSAP, BF, and RND.
Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron
Authors: Pötzl F. M. , Lobanov A. P. , Ros E. , Gómez J. L. , Bruni G. , Bach U. , Fuentes A. , Gurvits L. I. , Jauncey D. L. , Kovalev Y. Y. , Kravchenko E. V. , Lisakov M. M. , Savolainen T. , Sokolovsky K. V. , Zensus J. A. 
Published: February 2021

Context. Supermassive black holes in the centres of radio-loud active galactic nuclei (AGN) can produce collimated relativistic outflows (jets). Magnetic fields are thought to play a key role in the formation and collimation of these jets, but the details are much debated.
Aims. We study the innermost jet morphology and magnetic field strength in the AGN 3C 345 with an unprecedented resolution using images obtained within the framework of the key science programme on AGN polarisation of the Space VLBI mission RadioAstron.
Methods. We observed the flat spectrum radio quasar 3C 345 at 1.6 GHz on 2016 March 30 with RadioAstron and 18 ground-based radio telescopes in full polarisation mode.
Results. Our images, in both total intensity and linear polarisation, reveal a complex jet structure at 300 μas angular resolution, corresponding to a projected linear scale of about 2 pc or a few thousand gravitational radii. We identify the synchrotron self-absorbed core at the jet base and find the brightest feature in the jet 1.5 mas downstream of the core. Several polarised components appear in the Space VLBI images that cannot be seen from ground array-only images. Except for the core, the electric vector position angles follow the local jet direction, suggesting a magnetic field perpendicular to the jet. This indicates the presence of plane perpendicular shocks in these regions. Additionally, we infer a minimum brightness temperature at the largest (u, v)-distances of 1.1 × 1012 K in the source frame, which is above the inverse Compton limit and an order of magnitude larger than the equipartition value. This indicates locally efficient injection or re-acceleration of particles in the jet to counter the inverse Compton cooling or the geometry of the jet creates significant changes in the Doppler factor, which has to be > 11 to explain the high brightness temperatures.
High-accuracy estimation of magnetic field strength in the interstellar medium from dust polarization
Authors: Skalidis Raphael , Tassis Konstantinos 
Published: February 2021

Context. A large-scale magnetic field permeates our Galaxy and is involved in a variety of astrophysical processes, such as star formation and cosmic ray propagation. Dust polarization has been proven to be one of the most powerful observables for studying the field properties in the interstellar medium (ISM). However, it does not provide a direct measurement of its strength. Different methods have been developed that employ both polarization and spectroscopic data in order to infer the field strength. The most widely applied method was developed by Davis (1951, Phys. Rev., 81, 890) and Chandrasekhar & Fermi (1953, ApJ, 118, 1137), hereafter DCF. The DCF method relies on the assumption that isotropic turbulent motions initiate the propagation of Alfvén waves. Observations, however, indicate that turbulence in the ISM is anisotropic and that non-Alfvénic (compressible) modes may be important.
Aims. Our goal is to develop a new method for estimating the field strength in the ISM that includes the compressible modes and does not contradict the anisotropic properties of turbulence.
Methods. We adopt the following assumptions: (1) gas is perfectly attached to the field lines; (2) field line perturbations propagate in the form of small-amplitude magnetohydrodynamic (MHD) waves; and (3) turbulent kinetic energy is equal to the fluctuating magnetic energy. We use simple energetics arguments that take the compressible modes into account to estimate the strength of the magnetic field.
Results. We derive the following equation: B0 = √2πρδv/√δθ, where ρ is the gas density, δv is the rms velocity as derived from the spread of emission lines, and δθ is the dispersion of polarization angles. We produce synthetic observations from 3D MHD simulations, and we assess the accuracy of our method by comparing the true field strength with the estimates derived from our equation. We find a mean relative deviation of 17%. The accuracy of our method does not depend on the turbulence properties of the simulated model. In contrast, the DCF method, even when combined with the Hildebrand et al. (2009, ApJ, 696, 567) and Houde et al. (2009, ApJ, 706, 1504) method, systematically overestimates the field strength.
Conclusions. Compressible modes can significantly affect the accuracy of methods that are based solely on Alfvénic modes. The formula that we propose includes compressible modes; however, it is applicable only in regions with no self-gravity. Density inhomogeneities may bias our estimates to lower values.
Das Polypill-Modell: Konzeptionelle Überlegungen zu den körperlichen, psychischen und sozialen Wirkungen des Sports
Authors: Schneider Sven 
Published: February 2021

ZusammenfassungHintergrund Angesichts seiner mannigfaltigen physiologischen Wirkungen wird Sport in der Literatur zunehmend als „Polypille“ bezeichnet. Sport gleiche demnach einem pleiotrop wirksamen Medikament. Die Sportwissenschaft kritisiert diese eher klinische Sichtweise als zu einseitig und warnt vor einer Medikalisierung des Sports.Methode Der vorliegende Beitrag greift diesen Einwand auf und fasst die biopsychosozialen Wirkungen des Sports zusammen. Besondere Beachtung finden dabei die psychischen und sozialen Wirkungen sportlicher Aktivität. Die Überlegungen münden in einem konzeptionellen Modellentwurf, dem Polypill-Modell des Sports.Ergebnisse Der Sport wird zunächst in seine Organisationsformen differenziert. Anschließend werden die individuellen Wirkungen sportlicher Aktivität auf körperliche, psychische und soziale Ressourcen beschrieben: Diese erstrecken sich auf motorische, also konditionelle und koordinative, Fähigkeiten, auf kognitive, emotionale und motivationale Aspekte sowie auf selbstbezogene und fremdbezogene Sozialkompetenzen. Wenngleich – insbesondere regelmäßiger – Sport körperliche, psychische und soziale Ressourcen zu stärken vermag, bergen beispielsweise unphysiologische Belastungen, mangelhafte Betreuung und normative Strukturen dennoch stets ein individuelles latentes Schädigungspotenzial. Darüber hinaus werden die sportspezifischen Sozialisations- und Enkulturationsprozesse unter den Begriffen „Sozialisation in den Sport“, „Sozialisation im Sport“ und „Sozialisation durch den Sport“ in das Modell integriert. So können viele im Sport erlernte – insbesondere psychische und soziale – Kompetenzen auch für andere Lebensbereiche von Bedeutung sein.Schlussfolgerungen Unter dem Begriff der Polypille werden neben körperlichen auch psychische und soziale Wirkungen des Sports systematisiert. Das hier vorgeschlagene Polypill-Modell des Sports kann in der universitären und außeruniversitären Lehre ebenso eingesetzt werden wie in der konkreten Studien- und Trainingsplanung.
Zur Passung von Person und Sportaktivität
Authors: Schmid Julia , Sudeck Gorden , Conzelmann Achim 
Published: February 2021

ZusammenfassungEin Ziel der Sport- und Bewegungsförderung ist, eine möglichst gute Passung zwischen der Person und dem Sport herzustellen. Dabei sind insbesondere die sportbezogenen Motive und Ziele von Menschen in den Blick zu nehmen. Denn werden diese befriedigt, so fördert dies das Wohlbefinden und die Bindung an die Aktivität. Folgende Motive und Ziele lassen sich im Sport finden: Figur / Aussehen, Kontakt, Wettkampf / Leistung, Ästhetik, Ablenkung / Katharsis, Aktivierung / Freude, Fitness und Gesundheit. Wie wichtig diese Motive und Ziele für jemand sind, ist sehr unterschiedlich. Jede Person weist daher ein einzigartiges Motiv- und Zielprofil auf. Die Person-Sport-Passung kann gefördert werden, indem maßgeschneiderten Sportprogramme angeboten, eine bestehende Angebotspalette angepasst bzw. erweitert oder eine individuelle Sportberatung durchgeführt wird.
MultiPill Exercise: Konzeption eines individualisierten Bewegungsprogramms für Personen mit multiplen chronischen Erkrankungen an den Schnittstellen der Gesundheitsversorgung sowie des Freizeit- und Gesundheitssports
Authors: Schweda Simone , Sudeck Gorden , Schmid Julia , Janßen Pia , Krauß Inga 
Published: February 2021

ZusammenfassungBisher hat die Behandlung von Patienten mit mehreren chronischen Erkrankungen (Multimorbidität) wenig Aufmerksamkeit in der Gesundheitspolitik erhalten, obwohl chronische Erkrankungen heute zu den häufigsten Gesundheitsproblemen der Industrieländer gehören und nicht nur auf individueller Ebene, sondern auch aus ökonomischer Sicht eine große Herausforderung darstellen. Präventive Therapien erscheinen demzufolge zwingend notwendig. Obwohl der Nutzen von körperlicher Aktivität zur Prävention und Behandlung chronischer Erkrankungen bekannt ist, hat körperliche und sportliche Aktivität in der Therapie einen vergleichsweise geringen Stellenwert. Viele Personen scheitern an der regelmäßigen Integration von körperlichen und sportlichen Aktivitäten in Freizeit und Alltag. Ziel des vorliegenden Beitrags ist es, ein Interventionsprogramm vorzustellen, welches Personen mit Risikofaktoren oder bereits manifestierten Mehrfacherkrankungen auf dem Weg zu einer körperlich aktiven Lebensweise unterstützen soll. Das Konzept orientiert sich übergeordnet am biopsychosozialen Gesundheitsmodell der Internationalen Klassifikation der Funktionsfähigkeit, Behinderung und Gesundheit (ICF). Ein besonderes Augenmerk der Intervention liegt auf personalen und strukturellen Kontextfaktoren der Teilnehmenden. Die Intervention kennzeichnet sich im Wesentlichen durch eine Kombination systematischen körperlichen Trainings und einer gesundheitspädagogisch und -psychologisch fundierten Kompetenz- und Verhaltensorientierung mit Blick auf eine regelmäßige Fortführung körperlicher und sportlicher Aktivitäten. Neben einer spezifischen Berücksichtigung von individuellen sportbezogenen Motiven und Zielen werden weitere Förderfaktoren und Barrieren der Teilnehmerinnen und Teilnehmer zur Individualisierung des Programms einbezogen.
Clinico-pathological correlation of homologous recombination status in epithelial ovarian cancer: Surgeon’s perspective
Authors: Mukhopadhyay Asima , Curtin Nicola , Edmondson Richard 
Published: February 2021

Background: TCGA data using expensive multi-modality diagnostic platforms have shown that 50% epithelial ovarian cancers (EOCs) are estimated to be homologous recombination (HR) deficient (HRD). We developed a functional assay for HR using gamma H2AX-Rad51 immunofluoresence.[1]
Methods: Primary cultures were developed in 50 consecutive EOCs from ascetic fluid and HR assay was performed.
Results: 50% patients were HRD based on the functional assay and show improved ex-vivo chemosensitivity to PARP inhibitor (PARPi) (PPV = 92%, NPV = 100%). HRD patients showed improved platinum sensitivity (53.8% vs 16.7%), survival (12 month OS - 41.7% vs. 11.5%) and optimal cytoreduction (80% vs. 62%) rates compared to HR competent (HRC) tumours which are less responsive and represent an unmet clinical need.
Conclusions: Personalised surgical and chemotherapeutic strategies may be developed for HR stratified EOCs. Primary surgery may be the preferred approach in HRC due to poor chemoresponse; surgical expertise/environment should be optimised to ensure optimal surgical outcome. Intra-operative hyperthermic treatment and selective HR inhibitors may improve subsequent chemoresponse in HRC and are currently being investigated.
A Critical Analysis of Rectal Biopsy to Exclude Hirschsprung's Disease
Authors: Tan Yew-Wei , Chacon Carmen Sofia , Sherwood William , Haddad Munther , Choudhry Muhammad 
Published: February 2021

Abstract
Introduction Most Hirschsprung's disease (HD) are diagnosed in young children with increased risk (”red flag”). Older children (>6 months) require open rectal biopsy (ORB) with its own impact on risk and resources. We investigated if “red flag”, age, and sex used in combination could exclude HD.
Materials and Methods “Red flags” are risk factors associated with HD, including neonatal bowel obstruction, genetic association, failure of passage of meconium in <48 hours, infantile constipation, distension with vomiting, or family history. All rectal biopsies (2015–2018) were reviewed for indications, methods, and histopathological findings. Logistic regression analysis was adopted to assess predictive value of “red flag,” age, and sex (p < 0.05* was significant).
Results A total of 187 children underwent 84 suction rectal biopsies and 113 ORBs (n = 197 in total). Final histopathological diagnoses were non-HD (n = 154) and HD (n = 43). Total 78% of rectal biopsies were non-HD, of which 63% by ORB. Non-HD was associated with absence of “red flag” (49 vs. 16%*), increased age at biopsy (22 months vs. 28 days*), >6 months old (62 vs. 30%*), and female gender (54 vs. 16%*), compared with HD. In the absence of “red flag,” 7/82 (9%) had HD (negative predictive value = 91%). Logistic regression analysis found absent “red flag” predicted non-HD biopsy with odds ratio 4.77 (1.38, 16.47), corrected for age and sex.
Conclusion Negative rectal biopsy rate for HD is very high. The majority required ORB. Although “red flag” and gender, but not age, have strong predictive values, it is inadequate for excluding HD. This study supports the need for alternative strategies in excluding HD.
Diagnostic Value of Clinical Prediction Scores for Acute Appendicitis in Children Younger than 4 Years
Authors: Rassi Ricardo , Muse Florencia , Sánchez-Martínez José , Cuestas Eduardo 
Published: February 2021

Abstract
Introduction Acute appendicitis can be difficult to diagnose, especially in children < 4 years old. The aim of the present study was to assess the diagnostic value of Alvarado score (AS), appendicitis inflammatory response (AIR) score, and pediatric appendicitis score (PAS) in children younger than 4 years.
Materials and Methods All children younger than 4 years who underwent appendicectomy between 2005 and 2019 were included retrospectively. The diagnostic performance of the scores was analyzed using the area under the receiver-operating characteristic (ROC) curve and by calculating the diagnostic performances at optimal criterion value cutoff points.
Results In this study, 100 children were included (58 boys and 42 girls) with a median age of 39.5 (12–47) months. Ninety children were diagnosed with pathologically proven acute appendicitis. The area under ROC curve of AS was 0.73, AIR score was 0.79, and PAS was 0.69 (p > 0.05, respectively). In children with low risk of acute appendicitis, negative predictive values were 75.0% for AS, 50.0% for AIR score, and 66.7% for PAS (p < 0.05, respectively). The positive predictive values in children with high risk of acute appendicitis were of 92.7% for AS, 92.6% for AIR score, and 93.6% for PAS (p > 0.05, respectively). AS, AIR score, and PAS plus positive ultrasonography have 0.58, 0.49, and 0.88 area under ROC curve.
Conclusion The three scores can be of assistance in the suspicion of acute appendicitis. PAS markedly improved combined with positive ultrasonography, but none can be used in setting the diagnosis of acute appendicitis in young children.
Clinical Stratification of Pregnant COVID-19 Patients based on Severity: A Single Academic Center Experience
Authors: Berry Marissa , Wang Amanda , Clark Shannon M. , Harirah Hassan M. , Jain Sangeeta , Olson Gayle L. , Pacheco Luis D. , Saade George R. , Saad Antonio F. 
Published: February 2021

Objective This study aimed to describe baseline characteristics of a cohort of pregnant women infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and determine if these correlate with disease severity and perinatal outcomes.
Study Design This was a retrospective cohort trial conducted at the University of Texas Medical Branch Galveston, Texas. All pregnant women presented to our medical center, who were screened and tested positive for SARS-CoV-2 virus, were included. We stratified our study population in three groups: asymptomatic, symptomatic not requiring oxygen therapy, and patients requiring oxygen support to maintain oxygen saturation >94%. Relevant population characteristics, laboratory data, and maternal and neonatal outcomes were abstracted. A p-value <0.05 was considered statistically significant.
Results Between March and July 2020, 91 women tested positive for SARS-CoV-2 upon admission to our labor and delivery unit. Among these, 61.5% were asymptomatic, 34.1% were symptomatic, and 4.4% required oxygen support. Our population was mainly Hispanic (80.2%), multiparous (76.9%), obese (70.3%), and with a median age of 27 years. Median gestational age at symptom onset or diagnosis was 36 weeks. Significant differences were found between gestational age and disease severity. Maternal characteristics including age, body mass index (BMI), and presence of comorbid conditions did not appear to influence severity of SARS-CoV-2 infection. Significant laboratory findings associated with increasing disease severity included decreasing hemoglobin and white blood cell count, lymphopenia, and increasing levels of inflammatory markers including CRP, ferritin, and procalcitonin. Maternal and neonatal outcomes did not differ among groups. No SARS-CoV-2 was detected by polymerase chain reaction testing in neonates of mothers with COVID-19.
Conclusion Pregnant patients with COVID-19 infection are predominantly asymptomatic. Patients appear to be at increased risk for more severe infection requiring oxygen support later in pregnancy.
Key Points
Critical magnetic behavior in [Ag8/Co0.5]x64, [Ag8/Co1]x32 and [Ag16/Co1]x32 epitaxial multilayers
Authors: Navarro Enrique , Alonso María , Ruiz Ana , Magen Cesar , Urdiroz Unai , Cebollada Federico , Balcells Lluís , Martínez Benjamín , González Jesús M. , Palomares F. Javier 
Published: February 2021

We investigate the low temperature magnetic behavior of three epitaxial Co/Ag multilayers, grown onto MgO (001) substrates, with a nominal content per period of either half a monolayer or one monolayer of Co, and either 8 or 16 Ag monolayers. The samples were studied by X-ray reflectivity and diffraction, transmission electron microscopy, magnetometry and ac susceptometry. The results indicated a well defined stacking sequence in the growth direction, the number of periods and of Ag monolayers per period being coincident with the nominal values for each sample. The Co layers were found to be discontinuous and corresponded to a quasi-monodisperse in-plane distribution of Co nanoparticles embedded in a Ag(001) matrix. The zero-field cooled and field cooled temperature variations of the low field magnetization indicated the presence of irreversibilities at temperatures below 20 K. The ac field frequency (f) and temperature (T) dependencies of the real part of the susceptibility (χ′) corresponded to a Vogel–Fulcher behavior in the three samples, and indicated a frequency shift parameter (Γ) of the order of 4 x 10-2. For each sample, the experimental data corresponding to the variations of the imaginary part of the ac susceptibility (χ″) with f and T were found to collapse into a single curve according to the dynamic scaling law. Taken together, these results allow us to conclude that the three multilayers experience a phase transition of the paramagnetic to superspin glass type, driven by the dipolar interactions between the Co nanoparticles. Regarding the influence of the multilayer features, we found a clear dependence of the order parameter of the transition on the nominal number of Co monolayers per period.
Exploring the property space of periodic cellular structures based on crystal networks
Authors: Lumpe Thomas S. , Stankovic Tino 
Published: February 2021

Significance
Finding genuine novelty in cellular structures is inherently difficult due to the numerous possible topological and geometrical configurations and their complex mechanical and physical interrelations. Here, we draw inspiration from the incredibly rich collection of crystallographic periodic networks that we interpret from a structural point of view to identify and design novel cellular structures with unique properties. We provide a ready-to-use catalog with more than 17,000 unique entries and show how crystallographic symmetries relate to their mechanical properties. Our work provides a foundation to support future applications in science and engineering, ranging from mechanical and optical metamaterials, over bone tissue engineering, to the design of electrochemical devices.
Structural basis for differential recognition of phosphohistidine-containing peptides by 1-pHis and 3-pHis monoclonal antibodies
Authors: Kalagiri Rajasree , Stanfield Robyn L. , Meisenhelder Jill , La Clair James J. , Fuhs Stephen R. , Wilson Ian A. , Hunter Tony 
Published: February 2021

Significance
Phosphohistidine (pHis) is a labile posttranslational modification with two isoforms, 1-pHis and 3-pHis, involved in many cellular processes across the kingdoms of life. Due to its lability, it is difficult to study the pHis modification using standard biochemical tools and techniques. Previously, we developed monoclonal antibodies (mAbs) against the 1-pHis and 3-pHis modifications using stable phosphotriazolylalanine mimetics as immunogens. These antibodies are promising tools to uncover the role of pHis in eukaryotic cells. Here, we report the crystal structures of five of these mAbs bound to their cognate phosphotriazolylalanine peptides, thus providing insight into the structure–function relationships that guide pHis recognition and establishing a foundation for the structure-guided design of improved pHis antibodies.
The evolution of developmental thresholds and reaction norms for age and size at maturity
Authors: Nilsson-Örtman Viktor , Rowe Locke 
Published: February 2021

Significance
Why most—but not all—organisms mature earlier in better growth conditions remains a mystery. Theory suggest that a solution may lie in the existence and evolution of critical size thresholds during development. The threshold model makes two unique predictions on the evolution of reaction norms between species and the effect of food reductions within species. We test this model experimentally using five damselfly species aligned along an ephemeral–permanent gradient, finding strong support for each prediction. Permanent habitats favor large thresholds and early maturation in better conditions, whereas ephemeral habitats favor small thresholds producing the rarer pattern with delayed maturation. The evolution of developmental thresholds is critical for understanding natural and human-induced variation in age and size at maturity.