bluuebunny/crossref_metadata_2025 huggingface dataset:
De l’utilisation des technologies 3D numériques pour l’analyse, la planification et le rétrocontrôle d’un traitement orthodontique de troubles fonctionnels temporo-mandibulaires
Authors: Petitpas Laurent
Published: October 2020

Nous souhaitons présenter dans cet article, un cas clinique pédagogique d’une adolescente où les analyses numériques ont été utilisées tout au long de la gestion de sa reprise de traitement.

L’arrivée de la tomodensitométrie à faisceau conique (CBCT) et de logiciels informatiques 3D, permet aux orthodontistes de fournir des diagnostics, des simulations et des traitements plus précis. D’un point de vue éthique, il n’est pas acceptable de soigner sans utiliser les méthodes les plus bénéfiques aux patients.

En effet, les fichiers DICOM de CBCT renferment une multitude d’informations que nous ne possédions pas auparavant. Des techniques de segmentation par des logiciels de sélection par seuillage nous permettent de visualiser précisément les rapports radiculaires et osseux en 3D. Une connaissance précise de la position des racines dentaires et des bases osseuses améliore la détermination du succès du traitement orthodontique par une surveillance accrue.

De nos jours, compte tenu de la rapidité du développement technologique, une combinaison de scanners intra-oraux, d’enregistrements numériques 3D, de multi-bagues individualisés, d’arcs personnalisés, de collage indirect numérique, et d’aligneurs de finition deviendra bientôt une obligation de moyens orthodontiques.
Statistical Representations of a Dashboard to Monitor Educational Videogames in Natural Language
Authors: Solorzano Alcivar Nayeth I. , Loor Zambrano Robert , Gonzabay Yagual Stalyn , Vintimilla Burgos Boris X.
Published: October 2020

This paper explains how Natural Language (NL) processing by computers, through smart programs as a way of Machine Learning (ML), can represent large sets of quantitative data as written statements. The study recognized the need to improve the implemented web platform using a dashboard in which we collected a set of extensive data to measure assessment factors of using children’s educational games. In this case, applying NL is a strategy to give assessments, build, and display more precise written statements to enhance the understanding of children’s gaming behavior.We propose the development of a new tool to assess the use of written explanations rather than a statistical representation of feedback information for the comprehension of parents and teachers with a lack of primary level knowledge in statistics. Applying fuzzy logic theory, we present verbatim explanations of children’s behavior playing educational videogames as NL interpretation instead of statistical representations. An educational series of digital game applications for mobile devices, identified as MIDI (Spanish acronym of “Interactive Didactic Multimedia for Children”) linked to a dashboard in the cloud, is evaluated using the dashboard metrics. MIDI games tested in local primary schools helps to evaluate the results of using the proposed tool. The guiding results allow analyzing the degrees of playability and usability factors obtained from the data produced when children play a MIDI game. The results obtained are presented in a comprehensive guiding evaluation report applying NL for parents and teachers. These guiding evaluations are useful to enhance children’s learning understanding related to the school curricula applied to ludic digital games.
Liebe Leserin, lieber Leser,
Authors: Koch Uwe
Published: October 2020

„Stillstand ist Rückschritt“ ist ein auf ganz
unterschiedliche Sachverhalte zielender Slogan. Er kann sich auf die eigene
Persönlichkeit, aber auch auf soziale Institutionen oder Dienstleistungen
beziehen. Gemeint ist mit der Aussage, dass es immer
Optimierungsmöglichkeiten gibt und man gehalten ist, diese auch zu nutzen.
Dieser Anspruch sollte auch für die Gestaltung der Rehabilitation in
Deutschland gelten. Hier wird den Versicherten, insbesondere wenn man internationale
Vergleiche anstellt, ein qualitativ sehr gutes und flächendeckendes Angebot
angeboten. Aber auch dieses bedarf einer stetigen Überprüfung und
Weiterentwicklung.
Einfluss der thermischen Enthornung mit unterschiedlichem Schmerzmanagement auf die Gesundheit von Kälbern
Authors: Kretschmann Johannes , Scherf Lisa , Fischer Marie Luise , Kaiser Matthias , Müller Hendrik , Spilke Joachim , Mielenz Norbert , Möbius Gerd , Bittner Lilli , Steinhöfel Ilka , Baumgartner Walter , Starke Alexander
Published: October 2020

Gegenstand und Ziel Die thermische Enthornung von Kälbern stellt einen mit Schmerz und Stress verbundenen Eingriff dar. Verschiedene Verfahren der Schmerzausschaltung sowie die unmittelbaren Auswirkungen auf physiologische, biochemische und ethologische Prozesse wurden bereits ermittelt. Ziel der Studie war zu evaluieren, ob die Enthornung selbst, das Schmerzmanagement oder das Alter der Kälber zum Zeitpunkt des Eingriffs die Gesundheit der Tiere beeinflusst.

Material und Methode Die Studie wurde als randomisierte, dreifach verblindete, prospektive Untersuchung an 337 weiblichen Deutsch-Holstein-Kälbern durchgeführt. Die Enthornung der Tiere erfolgte zwischen dem 4. und 10. Lebenstag oder zwischen dem 15. und 28. Lebenstag. Jedes Kalb wurde dabei einer von 9 Behandlungsgruppen zugelost, die sich in Art und Umfang der analgetischen Komponenten (Sedation, Leitungsanästhesie, Antiphlogese vs. Plazebo) unterschieden. Alle Kälber, bis auf die aus der Gruppe der scheinenthornten, wurden thermisch enthornt und sämtliche Tiere unterlagen einer klinischen Überwachung beginnend vor bis 4 Wochen nach dem Eingriff. Die erhobenen Befunde wurden als Boniturnoten unter Verwendung des Schwellenwertkonzepts mit dem Statistikprogramm SAS ausgewertet.

Ergebnisse Die Enthornung beeinflusste die Gesundheit des Respirationsapparats der Kälber. Tiere, bei denen die Enthornung lediglich simuliert wurde, zeigten die niedrigsten Erkrankungsraten. Am häufigsten erkrankten Kälber, bei denen die Enthornung ohne Analgesie erfolgte. Die Varianten des Schmerzmanagements senkten das Risiko respiratorischer Erkrankungen in unterschiedlichem Maß. Die zu einem früheren Zeitpunkt enthornten Kälber wiesen seltener eine abweichende innere Körpertemperatur auf als ältere Kälber.

Schlussfolgerung Die Enthornung stellt ein Risiko für die Gesundheit des Respirationsapparats von Kälbern dar. Sind Hornloszüchtung oder die Haltung horntragender Tiere nicht möglich, kann durch ein adäquates Schmerzmanagement das Risiko respiratorischer Erkrankungen gesenkt werden. Die Enthornung zu einem frühen Zeitpunkt ist möglich und sinnvoll.

Klinische Relevanz Die Studie belegt die Bedeutung eines adäquaten Schmerzmanagements zur Enthornung für die Kälbergesundheit.
Tierschutzprobleme von der Aufzucht bis zur Schlachtung in Rinderbetrieben aus amtstierärztlicher Sicht
Authors: Scheibl Peter
Published: October 2020

Bei der amtlichen Kontrolle rinderhaltender Betriebe in Deutschland sind einige den Tierschutz betreffenden Verstöße regelmäßig zu beanstanden. In diesem Beitrag werden zunächst die rechtlichen und fachlichen Grundlagen für RinderhalterInnen sowie grundlegende Begriffe erläutert. Anschließend werden Tierschutzprobleme bei der Aufzucht von Kälbern und Jungrindern, der Haltung von Milch- und Mastrindern, dem Transport und der Nottötung von Rindern aus der Sicht der Veterinärbehörden diskutiert. Praktizierenden TierärztInnen soll vermittelt werden, wie ihre KollegInnen in den Veterinärämtern Tierschutzverstöße bewerten. Mit der Weitergabe dieser Bewertungsgrundlagen an die Klientel kann zur Vermeidung von Schmerzen und Leiden beim Rind beigetragen werden.
Estudo comparativo entre as escalas: “Subjective Elbow Value” e “Patient-rated Tennis Elbow Evaluation” aplicadas em pacientes com epicondilite lateral do cotovelo
Authors: Ikemoto Roberto Yukio , Almeida Luiz Henrique Oliveira , Motta Giovanna Galvão Braga , Kim Alexandre Se Moo , Lial Carlos Vitor Nunes , Claros Johny James
Published: October 2020

Objetivo Avaliar se a aplicação das escalas subjective elbow value (SEV) e Patient-rated Tennis Elbow Evaluation (PRTEE) apresentam resultados similares na avaliação de pacientes com epicondilite lateral do cotovelo.

Métodos Trinta e sete indivíduos com diagnostic de epicondilite lateral do cotovelo foram avaliados no ambulatório de cirurgia do ombro e cotovelo do nosso hospital. O diagnóstico foi realizado com a história clínica da patologia, exame físico, raio-x, e ultrassonográfia. Foram utilizadas as escalas SEV e PRTEE, e os resultados foram comparados estatisticamente, usando-se como nível de significância 5% (p ≥ 0,05).

Resultados Encontramos uma relação estatisticamente significante entre os valores obtidos pelas escalas SEV e PRTEE quando aplicadas no grupo de pacientes portadores de epicondilite lateral (p = 0,017).

Conclusão Subjective elbow value apresentou resultados similares ao PRTEE na avaliação de pacientes com diagnóstico de epicondilite lateral do cotovelo.
Failure of Fondaparinux in Autoimmune Heparin-Induced Thrombocytopenia
Authors: Sartori Michelangelo , Cosmi Benilde
Published: October 2020

Heparin-induced thrombocytopenia (HIT) is an immune adverse reaction to heparin that is associated with life-threatening thrombotic complications. More rarely, HIT may begin after stopping of heparin or after flushes of heparin (autoimmune HIT). Fondaparinux has been proposed as a candidate treatment for HIT, but there are few data on its use in autoimmune HIT. An 86-year-old man with a history of diabetes mellitus, arterial hypertension, and hypercholesterolemia was admitted to our hospital for carotid endarterectomy. During surgery, only one heparin dose of 5,000 U was used. Platelet count started to decrease on the 11th day after surgery. Since the patient was not receiving heparin treatment/prophylaxis, HIT was not suspected. On day 19, platelet count was 61 × 103/μL, and the patient was investigated for a diagnosis of HIT. Immunoglobulin (Ig)-G-specific enzyme-linked immunosorbent assay (ELISA) was positive and HIT was confirmed by a platelet aggregation test; fondaparinux 5 mg once a day was started. During fondaparinux treatment, platelet count did not increase and a lower leg deep vein thrombosis occurred. Fondaparinux was stopped and rivaroxaban 15 mg twice a day was started. Platelet count returned to base line after 10 days from fondaparinux withdrawal. There was no thrombotic event or bleeding complication during rivaroxaban treatment. Anecdotal evidence suggests risk of failure of fondaparinux treatment for autoimmune HIT and supports the use of rivaroxaban for treatment of HIT, justifying larger studies.
Pilot Study of Sham Feeding in Postoperative Neonates
Authors: Tucker Alyssa , Huang Eunice Y. , Peredo Julia , Weems Mark F.
Published: October 2020

Objective Sham feeding may enhance development of oral skills in neonates after bowel surgery and decrease stress levels in mothers. In this pilot study, we test the feasibility of sham feeding, identify safety hazards, and assess maternal satisfaction.

Study Design A convenience sample of 15 postoperative neonates was enrolled. Sham feeding with unfortified human milk was offered following a strict advancement protocol beginning with 5 mL once daily and increasing up to 30 mL, three times daily. Continuous gastric suction was used during sham feeding. Each mother completed a satisfaction survey. Sham-fed gastroschisis patients were compared with a historic cohort.

Results All 15 patients were able to sham feed. A total of 312 sham feeds were offered with a median of 23 sham events per patient. Four minor complications occurred during sham feeding. No differences were noted between 11 sham-fed gastroschisis patients and 81 historic controls. The mothers reported a decrease in stress after sham feeding using a 5-point score (3.8 ± 1.4 vs. 1.5 ± 0.7, p < 0.005) and 100% satisfaction with sham feeding.

Conclusion Sham feeding is feasible for neonates after bowel surgery and is highly rated by mothers.

Key Points
Pressure gradients in uniform magnetic fields induce unexpected instabilities in pair plasmas
Authors: Bandari Anashe
Published: October 2020

Plasmas consisting of electrons and positrons may have previously unexpected instability, which can have large impacts on astrophysical and lab-based phenomena.
Open-circuit voltage photodetector architecture for infrared imagers
Authors: Specht T. R. , Duran J. M. , Taghipour Z. , Fragasse R. , Tantawy R. , Ronningen T. J. , Ariyawansa G. , Reyner C. , Smith D. S. , Fuller E. , Khalil W. , Krishna S.
Published: October 2020

We theoretically and experimentally investigate the application of an open-circuit voltage photodetector (VocP) architecture for mid-wave infrared (MWIR, 3–5 μm) detection and imaging. In contrast to conventional reverse-bias (RB) operation of the diode, which generates a photocurrent that is proportional to the photon irradiance, we evaluate the potential of using unbiased diodes that generate an open-circuit voltage, VOC, under illumination. The predicted Noise Equivalent Differential Temperature (NEDT) of a VocP is inferior to conventional RB when we assume an infinite well capacity and fixed integration time, but the prediction reverses when the actual well capacity of a readout integrated circuit (ROIC) is taken into account. Therefore, for a focal plane array (FPA) with a ROIC, we predict superior NEDT for the VocP. To demonstrate this concept, we fabricated and tested a basic VocP unit-cell architecture by connecting the VOC anode of a MWIR photodiode to the gate of an n-type metal-oxide semiconductor transistor that is operated in sub-threshold. Very good agreement is obtained between the analytical model and the observed drain current of the transistor over three orders of photon irradiance (1015–1018 photons/sec-cm2). The decoupling of the diode photocurrent from the integration capacitor in the circuit leads to a lower dark current that allows for longer integration times and improved sensitivity. This potentially can have a great impact on the performance and functionality of FPAs, leading to FPAs with better NEDT at a higher operating temperature, wider dynamic range, and smaller pixel size leading to larger array formats.
Numerical characterization of Love waves dispersion in viscoelastic guiding-layer under viscous fluid
Authors: Bonhomme Jérémy , Oudich Mourad , Segura Chavez Pedro Alberto , Bellaredj Mohamed Lamine Fayçal , Bryche Jean-François , Beyssen Denis , Charette Paul G. , Sarry Frédéric
Published: October 2020

We present a finite element (FE) based model to accurately investigate the dispersion and attenuation of Love waves in a multilayered structure made of a piezoelectric substrate, a guiding layer, and a viscous fluid. The numerical model solves the general form of the wave equations that includes the materials anisotropy, piezoelectricity, and viscoelasticity. We express the wave equations for elastic waves in a particular formulation in order to solve an eigenvalue problem where the eigenvalue is the complex wavenumber k from which we can derive the phase velocity [ω/Re(k)] and the attenuation rate [Im(k)]. The numerical model enables us to study the effects of the interdigitated electrodes, the materials viscoelasticity and piezoelectricity, and the fluid's viscosity on the wave phase velocity and attenuation. Our FE based model will facilitate optimizing the design of anisotropic piezoelectric platforms for Love waves propagation under viscous fluid loading.
Fixed charges investigation in Al2O3/hydrogenated-diamond metal-oxide-semiconductor capacitors
Authors: Liu J. W. , Oosato H. , Da B. , Koide Y.
Published: October 2020

Electrical properties of Al2O3/hydrogenated-diamond (H-diamond) metal-oxide-semiconductor (MOS) capacitors are investigated and discussed in this study. Al2O3 gate dielectrics are deposited at 120, 200, and 300 °C by an atomic layer deposition technique. For the H-diamond MOS capacitors with Al2O3 deposited at 120, 200, and 300 °C, leakage current densities at an electric field of 3.0 MV cm−1 are 8.4 × 10−4, 7.1 × 10−6, and 7.5 × 10−5 A cm−2, respectively. A small decrease in the maximum capacitance of the Al2O3 (120 °C)/H-diamond MOS capacitor is observed when the measurement frequency is increased from 1 kHz to 100 kHz. However, the maximum capacitances of the Al2O3 (200 °C)/H-diamond and Al2O3 (300 °C)/H-diamond MOS capacitors are stable. Experimental flatband voltage in the capacitance–voltage curve of the Al2O3 (120 °C)/H-diamond MOS capacitor shifts to the left with respect to theoretical flatband voltage. However, they shift to the right for the Al2O3 (200 °C)/H-diamond and Al2O3 (300 °C)/H-diamond MOS capacitors. Therefore, when the deposition temperature of Al2O3 is increased from 120 to 300 °C, polarity of the fixed charges in the H-diamond MOS capacitors changes from positive to negative. This phenomenon is explained by the variations of negatively charged acceptors at the Al2O3/H-diamond interface and oxygen vacancies in the Al2O3 film.
Prussian blue analog Co3[Co(CN)6]2 as a cathode material for lithium–sulfur batteries
Authors: Zhang Zengcheng , Jiao Qing , Lin Changgui , Zhang Xianghua , Xu Yinsheng , Wu Jinghua , Jia Guang , Yao Xiayin
Published: October 2020

In this work, the authors proposed a unique strategy to prepare a high performance Lithium–Sulfur (Li–S) battery cathode by an N-rich nano-graphene hollow sphere from the Prussian blue analog Co3[Co(CN)6]2. The one-pot solution method with low cost materials was designed to synthesize the cathode by annealing with different temperatures and consistent HCl etching steps for the precursor. The Li–S batteries made by this precursor showed remarkable charge–discharge stability (570.4 mA h g−1 after 500 cycles at a 1 C current density) and outstanding rate performance (1145.5, 717.9, and 672.5 mA hg−1 at 0.1, 1.0, and 2.0 Ag−1 current densities) at 800 °C. The results indicated that the stable three-dimensional multi-layer hollow sphere structure relieved the volume expansion of sulfur, which had a significant impact on the polysulfide adsorption, inhibiting the “shuttle effect.” Also, the rich doping of nitrogen in this structure produced many defects and active sites that improved the interfacial adsorption of polysulfides. While Co3[Co(CN)6]2 shows its potential as a cathode material, the material design method used in this paper provides a unique approach to realizing a high performance sulfur cathode for Li–S batteries.
Seasonal variation in colleter exudates in Myrcia splendens (Myrtaceae)
Authors: Costa Isabela. S. C. , Lucena Eliseu M. P. , Bonilla Oriel H. , Guesdon Isabel R. , Coutinho Ítalo A. C.
Published: October 2020

Colleters are secretory structures that play a role in protecting meristems from dehydration. Little attention has been given to the effect of seasonal variation on colleter exudates. Therefore, this study aimed to characterise the main chemical groups found in colleter exudates as well as to correlate the chemical nature of the secretion with seasonal variation. We used Myrcia splendens as a model to understand seasonal variation in colleter exudates. For that, meristems and shoot apices of M. splendens were collected and subjected to standard anatomical techniques. In M. splendens, colleters arise from protodermal cells and are similar to trichomes. Mature colleters are conic and composed of a short stalk and a long secretory head. Histochemical analyses found that colleter exudates differed according to the seasonality. Composition of the secretions was more diverse in the dry season than in the wet season. During the dry season, colleters secreted five different compounds (i.e. total polysaccharides, mucilage–pectins, total proteins, total lipids and phenolic compounds), whereas in the wet season, only three compounds were found (i.e. total proteins, total lipids and phenolic compounds). Our study extends what was known in earlier works, demonstrating changes in colleter exudates due to environmental seasonality.
Life history plasticity affects the population structure and distribution of the widespread migratory fish Galaxias brevipinnis
Authors: Hicks Andy S. , Jarvis Matt G. , Easton Ryan R. , Waters Jonathan M. , David Bruno O. , Norman Marc D. , Closs Gerard P.
Published: October 2020

Partial migration, or variation in migratory propensity within populations, has been reported across a range of taxa, including fish. Otolith microchemistry has revealed a high degree of life history plasticity in many amphidromous species, with diadromous and non-diadromous recruitment occurring. We examined this plasticity and its effect on population structure, dispersal and recruitment in Galaxias brevipinnis, an amphidromous fish widespread around New Zealand. We used otolith microchemistry analyses to examine recruitment sources and fish surveys to assess abundance and size structure in two large river systems, each containing naturally formed lakes and no obvious physical barriers to migration. Otolith analyses revealed discrete recruitment sources for stream-resident populations, with marine recruitment supporting populations downstream from lakes and exclusively lake-derived recruitment for populations upstream of lakes. Although diadromous G. brevipinnis were abundant within 10km of the sea, the abundance and relative proportion of younger fish declined as distance upstream increased, until a lake was reached, at which point abundance and the proportion of small individuals increased. The results provide a strong indication that supply is limiting recruitment for G. brevipinnis as distance from pelagic larval habitat increases, and that discrete recruitment sources and population structuring exist even within drainages.
Three-dimensional deconvolution processing for STEM cryotomography
Authors: Waugh Barnali , Wolf Sharon G. , Fass Deborah , Branlund Eric , Kam Zvi , Sedat John W. , Elbaum Michael
Published: October 2020

Significance

Electron tomography is used to reveal the structure of cells in three dimensions (3D). The combination with cryogenic fixation provides a snapshot in time of the living state. However, cryotomography normally requires very thin specimens due to image formation by conventional phase contrast transmission electron microscopy (TEM). The thickness constraint can be relaxed considerably by scanning TEM (STEM), yet 3D reconstruction is still subject to artifacts inherent in the collection of data by tilted projections. We show here that deconvolution algorithms developed for fluorescence microscopy can suppress these artifacts, resulting in significant contrast enhancement. The method is demonstrated by cellular tomography of complex membrane structures and by segmentation of chromatin into distinct, contiguous domains of high and low density.
Behavior and mechanics of dense microgel suspensions
Authors: Nikolov Svetoslav V. , Fernandez-Nieves Alberto , Alexeev Alexander
Published: October 2020

Significance

Microgel suspensions are a fascinating class of soft materials comprising compliant colloidal particles that can deform, swell/deswell, and interpenetrate. Understanding the behavior of microgels in dense suspensions can guide the design of self-healing synthetic materials with novel mechanical properties and facilitate the development of mechanistic models for biological tissues. We harness mesoscale computer simulations to probe the fate of microgels during suspension compression and show that below space-filling microgels deform and slightly shrink, whereas above space-filling microgels mostly shrink and mildly interpenetrate. Furthermore, despite the markedly different mechanical responses associated with changes in particle density and interparticle interactions, we show that suspension mechanics can always be rationalized using the single-microgel bulk modulus, which thus arises as the key mechanical descriptor for the suspension.
Superhydrophobic surfaces for extreme environmental conditions
Authors: Lambley Henry , Schutzius Thomas M. , Poulikakos Dimos
Published: October 2020

Significance

Despite the critical role of air in bestowing surfaces with superhydrophobic properties, little consideration has been given to how the atmospheric composition affects the ability of engineered and natural surfaces to repel impinging droplets. We establish that both environmental conditions of reduced pressure and increased humidity can significantly decrease the performance of surfaces that are seemingly robust in ambient conditions. We explain the mechanism behind this by thermodynamically modelling the compressed air layer beneath the droplet immediately before impact and reveal a previously unreported surface failure mechanism stemming from condensation within the texture. We also demonstrate that through the addition of appropriately scaled nanotexture, it is possible to mitigate against the detrimental effects of these extreme environmental conditions.
Ancient genomes reveal tropical bovid species in the Tibetan Plateau contributed to the prevalence of hunting game until the late Neolithic
Authors: Chen Ningbo , Ren Lele , Du Linyao , Hou Jiawen , Mullin Victoria E. , Wu Duo , Zhao Xueye , Li Chunmei , Huang Jiahui , Qi Xuebin , Capodiferro Marco Rosario , Achilli Alessandro , Lei Chuzhao , Chen Fahu , Su Bing , Dong Guanghui , Zhang Xiaoming
Published: October 2020

Significance

We undertook an ancient genomic DNA investigation of large animal remains dated ∼5,200 y B.P. from the Tibetan Plateau. We provide compelling evidence that the present-day low-latitude tropical inhabitants
Bos gaurus
and
Dicerorhinus sumatrensis
once roamed as far north as the margin of the northeastern Tibetan Plateau (NETP) during the late Neolithic, pushing the historical gaur distribution from ∼29°N to ∼34°N. Further multidisciplinary exploration indicates that a high summer temperature in the late Neolithic might have facilitated the northward expansion of these tropical animals to the NETP, which enriched the biodiversity of wildlife and contributed to the exploration of the Tibetan Plateau as one of the last habitats for hunting game in East Asia.
Unexpected specificity within dynamic transcriptional protein–protein complexes
Authors: Henley Madeleine J. , Linhares Brian M. , Morgan Brittany S. , Cierpicki Tomasz , Fierke Carol A. , Mapp Anna K.
Published: October 2020

A key functional event in eukaryotic gene activation is the formation of dynamic protein–protein interaction networks between transcriptional activators and transcriptional coactivators. Seemingly incongruent with the tight regulation of transcription, many biochemical and biophysical studies suggest that activators use nonspecific hydrophobic and/or electrostatic interactions to bind to coactivators, with few if any specific contacts. Here a mechanistic dissection of a set of representative dynamic activator•coactivator complexes, comprised of the ETV/PEA3 family of activators and the coactivator Med25, reveals a different molecular recognition model. The data demonstrate that small sequence variations within an activator family significantly redistribute the conformational ensemble of the complex while not affecting overall affinity, and distal residues within the activator—not often considered as contributing to binding—play a key role in mediating conformational redistribution. The ETV/PEA3•Med25 ensembles are directed by specific contacts between the disordered activator and the Med25 interface, which is facilitated by structural shifts of the coactivator binding surface. Taken together, these data highlight the critical role coactivator plasticity plays in recognition of disordered activators and indicate that molecular recognition models of disordered proteins must consider the ability of the binding partners to mediate specificity.
Bifurcation of point vortex equilibria: four-vortex translating configurations and five-vortex stationary configurations
Authors: Tsai Ya-Lun
Published: October 2020

Point vortices in a plane form a dynamical system. A vortex equilibrium is a solution where all vortices move with a common velocity. The configuration is stationary or translating depending on whether the velocity is zero or not. In this paper, we study the bifurcation for four-vortex translating configurations and five-vortex stationary configurations. The number of distinct four-vortex translating configurations can be 0, 3, 4, 6. Among the nonzero cases, there are 1, 0, and 0, or 2 collinear ones, respectively. The number of distinct five-vortex stationary configurations can be 0, 2, 4, 6. In each case, all smaller or equal even numbers of collinear configurations among them are possible. We provide simple and clear necessary and sufficient conditions on nonzero real circulations for all the possible numbers of collinear and strictly planer equilibrium. How two or three equilibrium merge and then apart is also described. All configurations are studied through the minimal polynomial systems obtained and defined by O’Neil. The 4, 5-vortex systems contain two and three independent circulation parameters, respectively. We count the numbers of zeros by univariate polynomials after triangulating the polynomial systems. Information on the numbers of real or complex zeros and their intersection multiplicities for different components are glued together to study the bifurcation as parameters vary in

R

2

and

R

3

for the four-vortex and five-vortex cases, respectively. Many computations are assisted by a computer algebra system.
A prototype Multi-X-ray-source array (MXA) for digital breast tomosynthesis
Authors: Becker Amy E , Hernandez Andrew M , Boone John M , Schwoebel Paul R
Published: October 2020

The design and testing of a prototype Multi-X-ray-source Array (MXA) for digital breast tomosynthesis is reported. The MXA is comprised of an array of tungsten filament cathodes with focus cup grid-controlled modulation and a common rotating anode housed in a single vacuum envelope. Prototypes consisting of arrays of three-source elements and eleven-source-elements were fabricated and evaluated. The prototype sources demonstrated focal spot sizes of 0.3 mm at 45 kV with 50 mA. Measured x-ray spectra were consistent with the molybdenum anode employed, and the tube output (air kerma) was between 0.6 mGy/100 mAs at 20 kV and 17 mGy/100 mAs at 45 kV with a distance of 100 cm. HVL measurements ranged from 0.5 mm Al at 30 kV to 0.8 mm Al at 45 kV, and x-ray pulse widths were varied from 20 ms to 110 ms at operating frequencies ultimately to be limited by source turn-on/off times of ∼1 ms. Initial results of reconstructed tomographic data are presented.
Influences of magnetic field on the coexistence of diquark and chiral condensates in the Nambu–Jona–Lasinio model with axial anomaly
Authors: Zhang Xiao-Bing , Peng Fu-Ping , Wu Yun-Ben , Zhang Yi
Published: October 2020

In this paper, we study the influences of magnetic fields on the coexistence of diquark and chiral condensates in an extended Nambu–Jona–Lasinio model with QCD axial anomaly, as it relates to color-flavor-locked quark matter. Due to the coupling of rotated-charged quarks to magnetic fields, diquark condensates become split, and the coexistence region is thus superseded in favor of a specific diquark Bose–Einstein condensation (BEC), denoted as the BECI phase. For strong magnetic fields, we find that the BECI transition is pushed to larger quark chemical potentials. The effect of magnetic catalysis tends to disrupt the BEC–BCS (Bardeen–Cooper–Schrieffer) crossover predicted in previous works. For intermediate fields, the effect of inverse magnetic catalysis is observed, and the axial-anomaly-induced phase structure is essentially unchanged.
Photon polarization tensor in a magnetized plasma system
Authors: Chao Jingyi , Huang Mei
Published: October 2020

We investigate the photon polarization tensor at finite temperatures in the presence of a static and homogeneous external magnetic field. In our scheme, the summing of the Matsubara frequency is performed after Poisson resummation, which is easily completed and converges quickly. Moreover, the behaviors of finite Landau levels are presented explicitly. It shows a convergence while summing infinite Landau levels. Consequently, there is no necessity to truncate the Landau level in a numerical estimation. At zero temperature, the lowest Landau level (LLL) approximation is analytically satisfied for the vacuum photon polarization tensor. However, we examine that the LLL approximation is not enough for the thermal polarization tensor. The thermal tensor obtains non-trivial contributions from the finite-n Landau levels. And, photon spectra gains a large imaginary contribution in thermal medium, which is the so-called Landau damping. Finally, it is argued that the summation of Matsubara frequency is not commuted with Landau level ones, such conjecture is excluded in our calculations.
Soliton interactions and asymptotic state analysis in a discrete nonlocal nonlinear self-dual network equation of reverse-space type*
Authors: Yuan Cui-Lian , Wen Xiao-Yong
Published: October 2020

We propose a reverse-space nonlocal nonlinear self-dual network equation under special symmetry reduction, which may have potential applications in electric circuits. Nonlocal infinitely many conservation laws are constructed based on its Lax pair. Nonlocal discrete generalized (m, N – m)-fold Darboux transformation is extended and applied to solve this system. As an application of the method, we obtain multi-soliton solutions in zero seed background via the nonlocal discrete N-fold Darboux transformation and rational solutions from nonzero-seed background via the nonlocal discrete generalized (1, N – 1)-fold Darboux transformation, respectively. By using the asymptotic and graphic analysis, structures of one-, two-, three- and four-soliton solutions are shown and discussed graphically. We find that single component field in this nonlocal system displays unstable soliton structure whereas the combined potential terms exhibit stable soliton structures. It is shown that the soliton structures are quite different between discrete local and nonlocal systems. Results given in this paper may be helpful for understanding the electrical signals propagation.
Analysis of secondary electron emission using the fractal method*
Authors: Bai Chun-Jiang , Hu Tian-Cun , He Yun , Miao Guang-Hui , Wang Rui , Zhang Na , Cui Wan-Zhao
Published: October 2020

Based on the rough surface topography with fractal parameters and the Monte–Carlo simulation method for secondary electron emission properties, we analyze the secondary electron yield (SEY) of a metal with rough surface topography. The results show that when the characteristic length scale of the surface, G, is larger than 1 × 10−7, the surface roughness increases with the increasing fractal dimension D. When the surface roughness becomes larger, it is difficult for entered electrons to escape surface. As a result, more electrons are collected and then SEY decreases. When G is less than 1 × 10−7, the effect of the surface topography can be ignored, and the SEY almost has no change as the dimension D increases. Then, the multipactor thresholds of a C-band rectangular impedance transfer and an ultrahigh-frequency-band coaxial impedance transfer are predicted by the relationship between the SEY and the fractal parameters. It is verified that for practical microwave devices, the larger the parameter G is, the higher the multipactor threshold is. Also, the larger the value of D, the higher the multipactor threshold.
Pathological environment directed in situ peptidic supramolecular assemblies for nanomedicines
Authors: Chen Jiali , Zhao Yan , Yao Qingxin , Gao Yuan
Published: October 2020

Peptidic self-assembly provides a powerful method to build biomedical materials with integrated functions. In particular, pathological environment instructed peptidic supramolecular have gained great progress in treating various diseases. Typically, certain pathology related factors convert hydrophilic precursors to corresponding more hydrophobic motifs to assemble into supramolecular structures. Herein, we would like to review the recent progress of nanomedicines based on the development of instructed self-assembly against several specific disease models. Firstly we introduce the cancer instructed self-assembly. These assemblies have exhibited great inhibition efficacy, as well as enhanced imaging contrast, against cancer models both in vitro and in vivo. Then we discuss the infection instructed peptidic self-assembly. A number of different molecular designs have demonstrated the potential antibacterial application with satisfied efficiency for peptidic supramolecular assemblies. Further, we discuss the application of instructed peptidic self-assembly for other diseases including neurodegenerative disease and vaccine. The assemblies have succeeded in down-regulating abnormal Aβ aggregates and immunotherapy. In summary, the self-assembly precursors are typical two-component molecules with (1) a self-assembling motif and (2) a cleavable trigger responsive to the pathological environment. Upon cleavage, the self-assembly occurs selectively in pathological loci whose targeting capability is independent from active targeting. Bearing the novel targeting regime, we envision that the pathological conditions instructed peptidic self-assembly will lead a paradigm shift on biomedical materials.
How do countries specialize in agricultural production? A complex network analysis of the global agricultural product space
Authors: Campi Mercedes , Dueñas Marco , Fagiolo Giorgio
Published: October 2020

Using a complex-network perspective, this paper empirically explores the determinants of the process through which countries, given their capabilities, specialize in agricultural production. Using production data from the Food and Agriculture Organization (FAO) for the period 1993–2013, we characterize the agricultural production space as a time-sequence of bipartite networks, connecting countries to the agricultural products they produce. We then project this representation in the agricultural production spaces, linking countries or products according to their similarity in production profiles, and we identify properties and determinants underlying their evolution. We find that, despite the unprecedented pressure that food systems have been undergoing in recent years, the agricultural production space is a very dense network displaying well-defined and stable communities of countries and products. We also show that the observed country community structures are not only shaped by environmental conditions, but also by economic, socio-political, and technological factors. We conclude by discussing the implications of such findings on our understanding of the complex relationships involving production capabilities and specialization patterns.
Ecophysiological adjustments of a pine forest to enhance early spring activity in hot and dry climate
Authors: Wang Huanhuan , Gitelson Anatoly , Sprintsin Michael , Rotenberg Eyal , Yakir Dan
Published: October 2020

Climate change can impose large offsets between the seasonal cycle of photosynthesis and that in solar radiation and temperature which drive it. Ecophysiological adjustments to such offsets in forests growing under hot and dry conditions are critical for maintaining carbon uptake and survival. Here, we investigate the adjustments that underlie the unusually short and intense early spring productive season, under suboptimal radiation and temperature conditions in a semi-arid pine forest.

We used eddy covariance flux, meteorological, and close-range sensing measurements, together with leaf chlorophyll content over four years in a semi-arid pine forest to identify the canopy-scale ecophysiological adjustments to the short active season, and long seasonal drought.

The results reveal a range of processes that intricately converge to support the early spring peak (March) in photosynthetic activity, including peaks in light use efficiency, leaf chlorophyll content, increase in the absorption of solar radiation, and high leaf scattering properties (indicating optimizing leaf orientation). These canopy-scale adjustments exploit the tradeoffs between the yet increasing temperature and solar radiation, but the concurrently rapidly diminishing soil moisture. In contrast, during the long dry stressful period with rapidly declining photosynthesis under high and potentially damaging solar radiation, physiological photoprotection was conferred by strongly relaxing the early spring adjustments.

The results provide evidence for canopy-scale ecophysiological adjustments, detectable by spectral measurements, that support the survival and productivity of a pine forest under the hot and dry conditions, which may apply to large areas in the Mediterranean and other regions in the next few decades due to the current warming and drying trends.
The role of beliefs, expectations and values in decision-making favoring climate change adaptation—implications for communications with European forest professionals
Authors: Blennow K , Persson J , Gonçalves L M S , Borys A , Dutcă I , Hynynen J , Janeczko E , Lyubenova M , Merganič J , Merganičová K , Peltoniemi M , Petr M , Reboredo F , Vacchiano G , Reyer C P O
Published: October 2020

Beliefs, expectations and values are often assumed to drive decisions about climate change adaptation. We tested hypotheses based on this assumption using survey responses from 508 European forest professionals in ten countries. We used the survey results to identify communication needs and the decision strategies at play, and to develop guidelines on adequate communications about climate change adaptation. We observed polarization in the positive and negative values associated with climate change impacts accepted by survey respondents. We identified a mechanism creating the polarization that we call the ‘blocked belief’ effect. We found that polarized values did not correlate with decisions about climate change adaptation. Strong belief in the local impacts of climate change on the forest was, however, a prerequisite of decision-making favoring adaptation. Decision-making in favor of adaptation to climate change also correlated with net values of expected specific impacts on the forest and generally increased with the absolute value of these in the absence of ‘tipping point’ behavior. Tipping point behavior occurs when adaptation is not pursued in spite of the strongly negative or positive net value of expected climate change impacts. We observed negative and positive tipping point behavior, mainly in SW Europe and N-NE Europe, respectively. In addition we found that advice on effective adaptation may inhibit adaptation when the receiver is aware of effective adaptation measures unless it is balanced with information explaining how climate change leads to negative impacts. Forest professionals with weak expectations of impacts require communications on climate change and its impacts on forests before any advice on adaptation measures can be effective. We develop evidence-based guidelines on communications using a new methodology which includes Bayesian machine learning modeling of the equivalent of an expected utility function for the adaptation decision problem.
Grey matter network trajectories across the Alzheimer’s disease continuum and relation to cognition
Authors: Dicks Ellen , Vermunt Lisa , van der Flier Wiesje M , Barkhof Frederik , Scheltens Philip , Tijms Betty M ,   Alzheimer’s Disease Neuroimaging Initiative
Published: October 2020

Biomarkers are needed to monitor disease progression in Alzheimer’s disease. Grey matter network measures have such potential, as they are related to amyloid aggregation in cognitively unimpaired individuals and to future cognitive decline in predementia Alzheimer’s disease. Here, we investigated how grey matter network measures evolve over time within individuals across the entire Alzheimer’s disease cognitive continuum and whether such changes relate to concurrent decline in cognition. We included 190 cognitively unimpaired, amyloid normal (controls) and 523 individuals with abnormal amyloid across the cognitive continuum (preclinical, prodromal, Alzheimer’s disease dementia) from the Alzheimer’s Disease Neuroimaging Initiative and calculated single-subject grey matter network measures (median of five networks per individual over 2 years). We fitted linear mixed models to investigate how network measures changed over time and whether such changes were associated with concurrent changes in memory, language, attention/executive functioning and on the Mini-Mental State Examination. We further assessed whether associations were modified by baseline disease stage. We found that both cognitive functioning and network measures declined over time, with steeper rates of decline in more advanced disease stages. In all cognitive stages, decline in network measures was associated with concurrent decline on the Mini-Mental State Examination, with stronger effects for individuals closer to Alzheimer’s disease dementia. Decline in network measures was associated with concurrent cognitive decline in different cognitive domains depending on disease stage: In controls, decline in networks was associated with decline in memory and language functioning; preclinical Alzheimer’s disease showed associations of decline in networks with memory and attention/executive functioning; prodromal Alzheimer’s disease showed associations of decline in networks with cognitive decline in all domains; Alzheimer’s disease dementia showed associations of decline in networks with attention/executive functioning. Decline in grey matter network measures over time accelerated for more advanced disease stages and was related to concurrent cognitive decline across the entire Alzheimer’s disease cognitive continuum. These associations were disease stage dependent for the different cognitive domains, which reflected the respective cognitive stage. Our findings therefore suggest that grey matter measures are helpful to track disease progression in Alzheimer’s disease.
Repeated Coronavirus Disease 2019 Molecular Testing: Correlation of Severe Acute Respiratory Syndrome Coronavirus 2 Culture With Molecular Assays and Cycle Thresholds
Authors: Gniazdowski Victoria , Paul Morris C , Wohl Shirlee , Mehoke Thomas , Ramakrishnan Srividya , Thielen Peter , Powell Harrison , Smith Brendan , Armstrong Derek T , Herrera Monica , Reifsnyder Carolyn , Sevdali Maria , Carroll Karen C , Pekosz Andrew , Mostafa Heba H
Published: October 2020

Background

Repeated coronavirus disease 2019 (COVID-19) molecular testing can lead to positive test results after negative results and to multiple positive results over time. The association between positive test results and infectious virus is important to quantify.

Methods

A 2-month cohort of retrospective data and consecutively collected specimens from patients with COVID-19 or patients under investigation were used to understand the correlation between prolonged viral RNA positive test results, cycle threshold (Ct) values and growth of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in cell culture. Whole-genome sequencing was used to confirm virus genotype in patients with prolonged viral RNA detection. Droplet digital polymerase chain reaction was used to assess the rate of false-negative COVID-19 diagnostic test results.

Results

In 2 months, 29 686 specimens were tested and 2194 patients underwent repeated testing. Virus recovery in cell culture was noted in specimens with a mean Ct value of 18.8 (3.4) for SARS-CoV-2 target genes. Prolonged viral RNA shedding was associated with positive virus growth in culture in specimens collected up to 21 days after the first positive result but mostly in individuals symptomatic at the time of sample collection. Whole-genome sequencing provided evidence the same virus was carried over time. Positive test results following negative results had Ct values >29.5 and were not associated with virus culture. Droplet digital polymerase chain reaction results were positive in 5.6% of negative specimens collected from patients with confirmed or clinically suspected COVID-19.

Conclusions

Low Ct values in SARS-CoV-2 diagnostic tests were associated with virus growth in cell culture. Symptomatic patients with prolonged viral RNA shedding can also be infectious.