bluuebunny/crossref_metadata_2025 huggingface dataset:
Information Technology and Corporate Governance in Fraud Prevention
Authors: Juhandi Nendi , Zuhri Saefudin , Fahlevi Mochammad , Noviantoro Rinto , Nur abdi Muhammad , Setiadi
Published: November 2020

Information technology is a technology for obtaining, processing, storing and distributing various types of information files by utilizing computers and telecommunications born of strong drives to create new innovations and creativity that can overcome all laziness and slowness of human performance. The recent phenomenon of several large companies listed on the Indonesia Stock Exchange shows that there is an improper management of the company, especially in supervision, thereby reducing the value of the company. The result is proven that developed companies, especially in developed countries, use supervision not only as a leader but also technology that can automatically detect fraud and is useful as a step to prevent fraud in companies. Corporate governance is still lacking in Indonesia and other developing countries, making the level of supervision at the company does not run optimally so that the potential for fraud is still quite large. This research contributes to fill the void level of supervision in companies in Indonesia that are still experiencing fraud, so the solution in supervision is to maximize the role of information technology in companies in Indonesia.
Improvement of inventory control and cost efficiency Warteg ABC
Authors: Qasmal Maulana Fariz , Wachidin Widjaja Anton
Published: November 2020

This thesis discusses about case study Micro, Small, and Medium Enterprise (MSME) inventory control which is engaged in food and beverages industry, students of the Faculty of Economics and Business of UI, of 2020. The increasing number of MSMEs which is engaged in food and beverages industry has positive impact to the economy of Indonesia, but also leads to the increases of competitiveness among MSMEs. To compete with others in the food and beverages industry which is always growing year by year, MSMEs should be able to manage the inventory professionally. Warteg ABC is a MSME, engaged in the food and beverages industry, which is sell Indonesian cuisine. Warteg ABC was already operated for more or less 4 years in South Jakarta. Data is obtained using business coaching method, a qualitative research from the interview with the owner and observation, to mapping the MSME’s conditions and problems, continued with the corrective action to implement solution. The result shows that Warteg ABC did not have proper record for the inventory purchase decision, the amount of inventory and the calculation of inventory cost in managing their business on the daily activities. Thus, the solution that given is to improve the inventory control and cost efficiency. Implementation assessment can’t be carried out to support the results of the improvements because of the Covid-19 Pandemic that makes the MSME decided to close temporarily. This research is aimed to help Warteg ABC to improve the inventory control and cost efficiency.
A systematic study of silicon nanowires array fabricated through metal-assisted chemical etching
Authors: Zhang Shiying , Li Zhenhua , Xu Qingjun
Published: November 2020

Aligned and uniform silicon nanowires (SiNWs) arrays were fabricated with good controllability and reproducibility by metal-assisted chemical etching in aqueous AgNO3/HF etching solutions in atmosphere. The SiNWs formed on silicon were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), high-resolution transmission electron microscopy (HRTEM) and selected-area electron diffraction (SAED). The results show that the as-prepared SiNWs are perfectly single crystals and the axial orientation of the Si nanowires is identified to be parallel to the [111] direction, which is identical to the initial silicon wafer. In addition, a series of experiments were conducted to study the effects of etching conditions such as solution concentration, etching time, and etching temperature on SiNWs. And the optimal solution concentrations for SiNWs have been identified. The formation mechanism of silicon nanowires and silver dendrites were also discussed.
How the absorber thickness influences the formation of reverse bias induced defects in CIGS solar cells
Authors: Bakker Klaas , Rasia Alix , Assen Suzanne , Ben Said Aflouat Basma , Weeber Arthur , Theelen Mirjam
Published: November 2020

When a PV module is partially shaded, the shaded solar cells operate in a reverse bias condition. For Cu(In,Ga)Se2 cells this condition can cause defects that irreversibly reduce the output of these cells and the full module. In order to design robust shade-tolerant CIGS modules details need to be known of the conditions at which these defects will be formed. In this study a large number of cells were exposed to different reverse bias conditions. By using simple statistics the probability of the occurrence of defects as a result of reverse bias at any given voltage has been determined. Based on our experiments we have found that the absorber thickness is one of the main parameters that affects the shade-tolerance: the thicker the absorber, the more shade tolerant the CIGS module will be.
Electromagnetic Steklov eigenvalues: approximation analysis
Authors: Halla Martin
Published: November 2020

We continue the work of Camano et al. [SIAM J. Math. Anal. 49 (2017) 4376–4401] on electromagnetic Steklov eigenvalues. The authors recognized that in general the eigenvalues do not correspond to the spectrum of a compact operator and hence proposed a modified eigenvalue problem with the desired properties. The present article considers the original and the modified electromagnetic Steklov eigenvalue problem. We cast the problems as eigenvalue problem for a holomorphic operator function A(⋅). We construct a “test function operator function” T(⋅) so that A(λ) is weakly T(λ)-coercive for all suitable λ, i.e. T(λ)*A(λ) is a compact perturbation of a coercive operator. The construction of T(⋅) relies on a suitable decomposition of the function space into subspaces and an apt sign change on each subspace. For the approximation analysis, we apply the framework of T-compatible Galerkin approximations. For the modified problem, we prove that convenient commuting projection operators imply T-compatibility and hence convergence. For the original problem, we require the projection operators to satisfy an additional commutator property which concerns the tangential trace. The existence and construction of such projection operators remain open questions.
«Sororidad», rire et émotion montrée en interaction : étude sur la construction de l’identité femme-féministe dans un débat informel à Medellin, Colombie
Authors: Acosta Córdoba Luisa Fernanda
Published: November 2020

Nous proposons une analyse de cas d’un débat informel sur le féminisme, qui a eu lieu en 2018 à Medellin en Colombie. Il s’agit d’un court extrait, autour du motsororidad, où deux séquences de rire ont eu lieu. En nous intéressant au déroulement séquentiel de cet extrait, nous nous concentrons sur les différences entre ces deux occurrences de rire en tant que manières de montrer les émotions dans une interaction face au public. L’analyse séquentielle de cet extrait révèle, non seulement, des enjeux communs aux interactions publiques, mais aussi, et surtout, un processus plus large de co-construction et d’affiliation à l’identité femme-féministe. En effet, l’étude de ce corpus, grâce aux outils de l’analyse conversationnelle, permet d’observer que l’identité femme-féministe est performée aussi bien par des processus de partage et d’affiliation que de revendication individuelle.
Discours rapporté et mimétique de l'émotion vécue : le cas des soignants en psychiatrie
Authors: Maritaud Louis
Published: November 2020

L’évolution du système de soin, tournée vers de nouveaux modes de coopération et l’augmentation des intervenants auprès des patients, implique la nécessité pour les soignants de mutualiser l'information concernant le dossier du patient, notamment lors de réunions de relèves. Ce sont 19 enregistrements de réunions de relèves infirmières qui constituent notre corpus d'étude, que nous avons filmées durant 5 semaines dans un hôpital psychiatrique de la région lyonnaise.

Lors de ces réunions, une grande partie du discours des soignants est du discours rapporté (DR), au sein duquel les soignants peuvent actualiser un discours premièrement énoncé par quelqu’un, et le rendre ainsi audible à l'ensemble de l'équipe. Selon la forme qu'il revêt, le discours rapporté peut tendre vers une mimétique des propos tenus à l'origine, notamment dans le cas des discours rapportés directs. Dès lors, une certaine forme de mimesis peut être repérée dans les émotions véhiculées par le biais du DR. Qu'il s'agisse de l'expression d'émotions relatives à la pathologie du malade (anxiété, angoisse...) ou d'émotions n’ayant pas de rapport direct avec les troubles pris en charge dans des structures psychiatriques, nous verrons que le DR, dans les réunions de relève infirmière, joue un rôle prépondérant dans l'expression émotive du patient face à l'équipe soignante.
L’intentionnalité des émotions dans l’analyse du discours radiophonique. Étude de cas d’une émission informative colombienne
Authors: Osorio Ruiz Natalia Marcela
Published: November 2020

Cet article vise à observer les manifestations émotionnelles qui émergent dans le discours radiophonique informatif d’une station colombienne, Caracol Radio et, plus particulièrement, de son émission matinale «6 AM Hoy por hoy». Dans une démarche ethnographique, cette recherche s'appuie sur un corpus où les enregistrements vidéo réalisés en studio donnent accès à des détails spécifiques du professionnalisme journalistique. Avec une approche d'étude qualitative et longitudinale, cette contribution vise à analyser le traitement des émotions dans deux extraits. Cette étude a été réalisée sous le prisme du « parcours émotionnel », tel que défini par Plantin, Traverso et Vosghanian [17], et la différence entre une émotion intentionnellement manifestée et une émotion intentionnellement cachée. Dans l'analyse effectuée, la multimodalité est prise en compte. En effet, l'aspect corporel des acteurs médiatiques ainsi que les changements phono-prosodiques sont considérés comme significatifs, car la visée pathémique est construite par la situation dans son ensemble.
L’octogone des événements émotionnels : un modèle pour comparer la gestion des émotions à un âge précoce
Authors: Feig Éva
Published: November 2020

Pour que les adultes travaillant dans des crèches ou écoles maternelles bi-plurilingues puissent comprendre le comportement co-régulatif de leurs collègues, issus d'une autre langue-culture, nous développons un nouveau modèle sous forme d'un diagramme Kiviat qui se fonde sur ce qu'on peut observer comme adulte au niveau intra-individuel pendant une situation de charge émotionnelle vécue par l'enfant (ici nommé événement émotionnel). Le modèle prend en considération les différentes dimensions qui caractérisent l'événement émotionnel vécu par l'enfant de même que sa gestion par l'adulte. Il visualise l'instant observé selon huit axes, à savoir : la valence émotionnelle, l'intensité du ressenti enfantin, la modalité du traitement offert par l'adulte, le degré de verbalisation du ressenti offert par l'adulte, la familiarité de l'enfant avec les mots utilisés par l'adulte, la sémiotisation des émotions du côté adulte, la focalisation plus ou moins centrée sur les émotions de l'enfant et la situationalité ou le degré d'induction situationnelle du vécu. Sur la base des observations faites dans quatre crèches franco-allemandes de l'espace du Rhin supérieur en 2018, il est possible de montrer l'applicabilité pratique du modèle pour des études interculturelles. De plus, l'abstraction des figures qui reflètent la stratégie de co-régulation des émotions mise en place par chaque pédagogue permet d'identifier des congruences comportementales transculturelles entre les professionnels francophones et germanophones qui ont réussi à établir une culture pédagogique partagée, voire une approche « interdidactique » selon Puren [7].
Interaction of the business community with the state authorities as a factor in the development of the Arctic zone of the Russian Federation
Authors: Bespalov Sergey , Vorotnikov Alexander
Published: November 2020

The development of the Arctic zone of the Russian Federation, as well as the development of the Arctic regions of the Russian Federation and its industrial exploration, requires solving many complex problems, including the creation of new highly efficient technologies for resource extraction and processing, better organization of production activities, transport, logistics, ensuring international standards of environmental safety, conservation and support of indigenous peoples, and many more. The current stage of the Arctic development and exploration requires highly effective organizational systems, the activities of which are determined by the interaction of the state and business structures.
Wastewater treatment of mining enterprises from nitrogen compounds in the Arctic
Authors: Korotaeva Anna
Published: November 2020

Open pit mining using explosives based on ammonium nitrate leads to wastewater pollution with nitrogen compounds. In case of insufficient wastewater treatment, pollutants enter surface-water bodies. Excessive concentration of nitrogen compounds in water leads to the development of the process of eutrophication, which adversely affects the vital activity of aquatic organisms and humans. At the moment, a common method of wastewater treatment from nitrogen compounds is a biological treatment method using devices such as aeration chambers, oxidation tanks and slim filters. An alternative option for biological treatment is the introduction of algae into wastewater. In the conditions of the Arctic, it is difficult to carry out biological treatment using algae due to low temperatures throughout the year. In this study, the feasibility of using the frost-resistant strain Chlorella kessleri VKPM A1-l1ARW for the effluents treatment from nitrogen compounds was tested. Model solutions with a known nitrates concentration were used. Experiments were carried out at two specified temperatures for comparison. The results showed that by the end of the 10-day experiment, the nitrates extraction efficiency at standard temperature (20 °C) was from 40.3% to 71.8%, at low temperature (3 °C) was from 30.4% to 73.6%.
Prüfungsthema: Krankheitsursachen
Authors: Schmid Eva C.
Published: November 2020

In diesem HPA-Prüfungstrainer beschäftigen sich alle Fragen mit Krankheitsursachen.
Sei biegsam wie der Bambus
Authors: Klaus Jessica
Published: November 2020

Der Bambus ist ein Sinnbild für Stärke, Ausdauer sowie Flexibilität und eine vielversprechende Pflanze bei Burnout und degenerativen Wirbelsäulenerkrankungen.
Sportwetten: Expertise oder Glück? Ein systematischer Review über Tippstudien
Authors: Kalke Jens , Schmidt Christiane S. , Hayer Tobias
Published: November 2020

Glücksspiele zeichnen sich unter anderem durch ihren zufallsbasierten Spielausgang aus. Im Fokus des vorliegenden systematischen Reviews steht die Frage, ob Sportwetten als Glücksspiel einzustufen sind oder alternativ ein Geschicklichkeitsspiel darstellen, bei dem bestimmte Kompetenzen der Spielteilnehmenden bei der Vorhersage von Sportereignissen maßgeblich zum Tragen kommen. Im Zuge einer systematischen Literaturrecherche konnten insgesamt 9 Tippstudien gefunden werden, welche die Einschlusskriterien erfüllten, und in denen verschiedene Personengruppen gegeneinander und/oder gegen den Zufall auf den Ausgang realer Spielereignisse wetten. Nahezu alle Studien zeigten, dass gewisse Kenntnisse, Fähigkeiten oder Fertigkeiten beim Sportwetten keine bedeutsame Rolle spielen. Dieser Sachverhalt gilt unabhängig von der Sportart, dem konkreten Sportereignis oder bestimmten Studienparametern. Entsprechend sollten Sportwetten im rechtlichen wie politischen Sinne zur Kategorie der Glücksspiele zählen und die entsprechenden Maßnahmen des Jugend- und Spielerschutzes aus dem Glücksspielbereich greifen. Ein zentrales Ziel besteht dabei in der Vorbeugung der Entstehung von kognitiven Verzerrungen wie Kontrollillusionen bzw. dem Irrglauben, beim Sportwetten durch die eigene Expertise Geld verdienen zu können.
Regionale Verteilung der Cochlea-Implantat (CI)-versorgenden Einrichtungen in Deutschland
Authors: Stöver T. , Zeh R. , Gängler B. , Plontke S. K. , Ohligmacher S. , Deitmer T. , Hupka O. , Welkoborsky H. J. , Schulz M. , Delank W. , Strobel M. , Guntinas-Lichius O. , Lang S. , Dietz A. , Dazert S. , Diensthuber M.
Published: November 2020

Die Versorgung von Patienten mit einer hochgradigen Schwerhörigkeit oder Taubheit mit einem Cochlea-Implantat (CI) stellt heute in Deutschland einen Standard dar. Umso überraschender ist es, dass kaum Daten zur aktuellen Anzahl der CI-versorgenden Einrichtungen (CI-Kliniken) und zu deren geografischer Verteilung existieren. Der Selbsthilfeverband Deutsche Cochlea Implantat Gesellschaft (DCIG) e. V. und die Deutsche Gesellschaft für Hals-Nasen-Ohrenheilkunde, Kopf- und Halschirurgie (DGHNO-KHC) haben daher eine Umfrage zur Erfassung der regionalen Verteilung, des Leistungsspektrums, der Berücksichtigung existierender Qualitätsstandards sowie der Zusammenarbeit mit Patientenselbsthilfe-Organisationen der einzelnen CI-versorgenden Einrichtungen initiiert.

Hierfür wurden insgesamt 170 Kliniken für Hals-Nasen-Ohrenheilkunde bzw. deren ärztliche Leiter (37 Lehrstuhlinhaber und 133 Chefärzte) per E-Mail kontaktiert und mittels Fragebogens befragt. Die Befragung erfolgte von Oktober 2019 bis Februar 2020.

Von den 170 kontaktierten Kliniken nahmen 71 (41,8 %) an der Umfrage teil. Hiervon bestätigten 70 Kliniken (98,6 %), CI-Operationen durchzuführen. Damit gaben 41,8 % aller kontaktierten Kliniken an, CI-Operationen durchzuführen (70 von 170 Kliniken), während diese Information von 99 Kliniken nicht verfügbar war. Alle 70 CI-versorgenden Einrichtungen (100 %) gaben an, CI-Operationen an Erwachsenen, 60 Kliniken (85,7 %) ebenfalls bei Kindern (< 18 Jahre) durchzuführen. 36 Kliniken (51,4 %) berichteten, dass die Gesamtanzahl der CI-Operationen an ihrer Einrichtung im Jahr 2018 mehr als 50 betrug. In 64 Kliniken (91,4 %) werden, nach den erhobenen Daten, die Empfehlungen der DGHNO-KHC zur CI-Versorgung (gemäß Weißbuch CI-Versorgung, Stand 2018) berücksichtigt. Eine Zusammenarbeit der Klinik mit der CI-Selbsthilfe wurde von 67 Kliniken (95,7 %) angegeben. Die geografische Verteilung der CI-versorgenden Einrichtungen, die an der Umfrage teilgenommen haben, zeigte ein heterogenes Verteilungsmuster zwischen den einzelnen Bundesländern und auch innerhalb der jeweiligen Bundesländer.

Die hier präsentierte Arbeit ist eine erste Standortbestimmung im Hinblick auf die regionale Verteilung der CI-versorgenden Einrichtungen in Deutschland. Auffällig ist eine Clusterbildung der CI-Kliniken in Ballungsräumen, teils mit mehreren Einrichtungen in einer Stadt. Erfreulich ist die weit überwiegende Beachtung qualitätsbezogener Aspekte, wie die Berücksichtigung des CI-Weißbuchs der DGHNO-KHC und die Zusammenarbeit mit der Patientenselbsthilfe. Limitationen der Studie ergeben sich aus der begrenzten Teilnahme an der Umfrage (41,8 % der kontaktierten Kliniken).
C–O Bond Activation as a Strategy in Palladium-Catalyzed Cross-Coupling
Authors: Leitch David C. , Becica Joseph
Published: November 2020

The activation of strong C–O bonds in cross-coupling catalysis can open up new oxygenate-based feedstocks and building blocks for complex-molecule synthesis. Although Ni catalysis has been the major focus for cross-coupling of carboxylate-based electrophiles, we recently demonstrated that palladium catalyzes not only difficult C–O oxidative additions but also Suzuki-type cross-couplings of alkenyl carboxylates under mild conditions. We propose that, depending on the reaction conditions, either a typical Pd(0)/(II) mechanism or a redox-neutral Pd(II)-only mechanism can operate. In the latter pathway, C–C bond formation occurs through carbopalladation of the alkene, and C–O cleavage by β-carboxyl elimination.

1 Introduction

2 A Mechanistic Challenge: Activating Strong C–O Bonds

3 Exploiting Vinylogy for C–Cl and C–O Oxidative Additions

4 An Alternative Mechanism for Efficient Cross-Coupling Catalysis

5 Conclusions and Outlook
Stereoselective Synthesis of (4S,5S)-5-Vinyloxazolidin-2-one-4-carboxylate as a β-Vinylserine Synthetic Equivalent by Vinyl Grignard Addition to an N-Tosyl Version of Garner’s Aldehyde
Authors: Nolen Ernest G. , Cao Yuqi M. , Lewis Brynn D. , Powers Madison H. , Thompson Andrew W. , Bennett John M.
Published: November 2020

A highly efficient synthesis of a β-vinylserine synthetic equivalent is reported that exploits the stereodirecting effect of the N-toluenesulfonamide in an anti-diastereoselective (8.5:1) vinyl Grignard addition to an analogue of Garner’s aldehyde. Both aryl and alkyl ­Grignards are shown to give increased anti-selectivity compared with N-Boc Garner’s aldehyde.
When It Doesn't Fit: Congenital Anomalies of the Choledochus
Authors: Reusens Helena , Davenport Mark
Published: November 2020

Introduction Congenital choledochal malformations (CCMs) are characterized by intra- and/or extrahepatic bile duct dilatation. Five basic types (1–5) are recognized in Todani's classification and its modifications, of which types 1 and 4 typically have an associated anomalous pancreatobiliary junction and common channel (CC). We describe two cases with previously undescribed features.

Case Report 1 Antenatal detection of a cyst at porta hepatis was made in an otherwise normal girl of Iranian parentage. She was confirmed to be a CCM (20 mm diameter), postnatally, with no evidence of obstruction. Surgical exploration was performed at 12 weeks. She had an isolated cystic dilatation of the right-hepatic duct only. The left-hepatic duct and common bile duct (CBD) were normal without a CC. Histology of the resected specimen showed stratified squamous epithelium.

Case Report 2 A preterm (31 weeks of gestation) boy of Nigerian parentage was presented. His mother was HIV + ve and he was treated with nucleoside reverse transcriptase inhibitors following birth. He had persistent cholestatic jaundice and a dilated (10 mm) bile duct from birth. Although the jaundice resolved, the dilatation persisted and increased, coming to surgery aged 2.5 years. This showed cystic dilatation confined to the common hepatic duct, and otherwise normal distal common bile duct and no CC.

Result Both underwent resection with the Roux-en-Y hepaticojejunostomy reconstruction to the transected right-hepatic duct alone in case 1, leaving the preserved left duct and CBD in continuity, and to the transected common hepatic duct in case 2.

Conclusions Neither choledochal anomaly fitted into the usual choledochal classification and case 1 appears unique in the literature.
The Dutch Incidence of Infantile Hypertrophic Pyloric Stenosis and the Influence of Seasons
Authors: van den Bunder Fenne A. I. M. , Allema Jan Hein , Benninga Marc A. , de Blaauw Ivo , van de Brug Tim , den Dulk Marcel , Hulscher Jan B. F. , Keyzer-Dekker Claudia M. G. , Witvliet Marieke J. , van Heurn Ernest L. W. , Derikx Joep P. M.
Published: November 2020

Introduction Studies report contradicting results on the incidence of infantile hypertrophic pyloric stenosis (IHPS) and its association with seasons. We aim to assess the IHPS incidence in the Netherlands and to determine whether seasonal variation is present in a nationwide cohort.

Materials and Methods All infants with IHPS hospitalized in the Netherlands between 2007 and 2017 were included in this retrospective cohort study. Incidence rates per 1,000 livebirths (LB) were calculated using total number of LB during the matched month, season, or year, respectively. Seasonal variation based on month of birth and month of surgery was analyzed using linear mixed model and one-way ANOVA, respectively.

Results A total of 2,479 infants were included, of which the majority was male (75.9%). Median (interquartile range) age at surgery was 34 (18) days. The average IHPS incidence rate was 1.28 per 1,000 LB (variation: 1.09–1.47 per 1,000 LB). We did not find a conclusive trend over time in IHPS incidence. Differences in incidence between season of birth and season of surgery were not significant (p = 0.677 and p = 0.206, respectively).

Conclusion We found an average IHPS incidence of 1.28 per 1,000 LB in the Netherlands. Our results showed no changing trend in incidence and no seasonal variation.
A novel high-power waveguide phase shifter with continuous linear phase adjustment
Authors: Yuan Cheng-Wei , Yu Long-Zhou , Zhang Qiang , Xu Liang , Zhao Xu-Hao
Published: November 2020

A novel all-metal phase shifter with continuous linear phase adjustment for high-power microwave applications is presented and tested in this paper. The phase adjustment is achieved through the rotation of a phase reverser for a circularly polarized wave, and the output phase accomplishes a phase adjustment range of 360° by rotating the phase reverser for 180°. Due to the symmetrical characteristics, its position after rotating 180° is the same as the initial position, which can achieve continuous phase adjustment and avoid phase mutation. Simulation results indicate that the phase shifter achieves the transmission efficiency greater than 99.90% at a center frequency of 8.4 GHz, and the bandwidth of transmission efficiency greater than 98.00% is up to 50 MHz. Experiments are carried out and the measured results are in good agreement with simulation. To sum up, the power capacity of this phase shifter is estimated to be more than 80 MW under vacuum conditions (<10−3 Pa), and it can be applied to fast continuous high-power beam-steerable antenna arrays or mode conversion systems.
Homoclinic chaos in the Rössler model
Authors: Malykh Semyon , Bakhanova Yuliya , Kazakov Alexey , Pusuluri Krishna , Shilnikov Andrey
Published: November 2020

We study the origin of homoclinic chaos in the classical 3D model proposed by Rössler in 1976. Of our particular interest are the convoluted bifurcations of the Shilnikov saddle-foci and how their synergy determines the global bifurcation unfolding of the model, along with transformations of its chaotic attractors. We apply two computational methods proposed, one based on interval maps and a symbolic approach specifically tailored to this model, to scrutinize homoclinic bifurcations, as well as to detect the regions of structurally stable and chaotic dynamics in the parameter space of the Rössler model.
Pre-pressure influences on the traveling wave ultrasonic motor performance: A theoretical analysis with experimental verification
Authors: Wang Hongxing , Pan Zhengyang , Zhu Hua , Guo Yong
Published: November 2020

In order to improve the output performance of the rotating traveling wave ultrasonic motor and study the optimal pre-pressures under different loads, the theoretical calculation and experimental verification on a TRUM-70H ultrasonic motor were carried out. The dynamic model of an ultrasonic motor is established, and the influence of pre-pressure on the mechanical properties of the ultrasonic motor is analyzed. Taking the TRUM-70H ultrasonic motor as the object of study, the relationship between the optimum pre-pressure and the load torque is analyzed. A multi-functional testing platform for an ultrasonic motor is built to verify the theoretical derivation results, and the reason for the error is also pointed out. According to the conclusion, the pre-pressure should be selected according to the load when the ultrasonic motors are assembled. The results show that there is a coupling relationship between the pre-pressure and the load torque on the speed of the ultrasonic motor. In the effective working range of the ultrasonic motor, the optimum pre-pressure is approximately linearly positively correlated with the load torque. When the pre-pressure is set according to the actual load demand during assembly, the output efficiency of the ultrasonic motor can be improved.
Particle acceleration and pressure gradient in a solitary wave traveling over a horizontal bed
Authors: Lin Chang , Kao Ming-Jer , Yang James , Raikar Rajkumar Venkatesh , Yuan Juan-Ming , Hsieh Shih-Chun
Published: November 2020

This study presents experimental data on the hydrodynamic features of a nonlinear solitary wave of height H0 = 2.9 cm propagating over a horizontal bed in otherwise still water depth h0 = 8.0 cm. High-speed particle image velocimetry is used to quantify the local and convective particle accelerations and pressure gradients under the solitary wave. It is found that the magnitudes of the horizontal and vertical particle local accelerations are invariably larger than their convective counterparts, highlighting the important contribution of local acceleration to the pressure gradient in a solitary wave. The dimensionless pressure gradient in the horizontal direction is favorable, zero, and adverse for time before, at, and after the wave crest passes the section of interest. The dimensionless adverse pressure gradient exhibits a maximum for the dimensionless time T[=t(g/h0)1/2, where g is the gravitational acceleration and t is the time with respect to the crest passing the section] = 1.39, at which the dimensionless local acceleration has a negative maximum. Subsequently, flow reversal takes place above the bed surface. The relationship is elucidated between flow reversal at the bed surface and the evolution of the adverse pressure gradient in the near-bed zone, where uniform horizontal/free stream velocity exists.
Negative-charge-storing mechanism of potassium-ion SiO2-based electrets for vibration-powered generators
Authors: Nakanishi Toru , Miyajima Takeshi , Chokawa Kenta , Araidai Masaaki , Toshiyoshi Hiroshi , Sugiyama Tatsuhiko , Hashiguchi Gen , Shiraishi Kenji
Published: November 2020

A potassium-ion electret, which is a key element of vibration-powered microelectromechanical generators, can store negative charge almost permanently. However, the mechanism by which this negative charge is stored is still unclear. We theoretically study the atomic and electronic structures of amorphous silica (a-SiO2) with and without potassium atoms using first-principles molecular-dynamics calculations. Our calculations show that a fivefold-coordinated Si atom with five Si–O bonds (an SiO5 structure) is the characteristic local structure of a-SiO2 with potassium atoms, which becomes negatively charged and remains so even after removal of the potassium atoms. These results indicate that this SiO5 structure is the physical origin of the robust negative charge observed in potassium-ion electrets. We also find that the SiO5 structure has a Raman peak at 1000 cm−1.
Michler’s hydrol blue elucidates structural differences in prion strains
Authors: Xiao Yiling , Rocha Sandra , Kitts Catherine C. , Reymer Anna , Beke-Somfai Tamás , Frederick Kendra K. , Nordén Bengt
Published: November 2020

Significance

Amyloids are protein fiber aggregates that are associated with both pathology, e.g., neurodegenerative diseases, and functionality, e.g., adaptation to environmental changes in yeasts. A particular property of amyloid fibrils is their ability to show structural variations among different fibrils formed by the same polypeptide chain, a phenomenon known as polymorphism. It is becoming increasingly important to be able to distinguish between amyloid polymorphs because they can cause pathologically distinct transmissible diseases. Here we describe a fluorescent amyloid dye that can differentiate between amyloid polymorphs.
Discovery of small-molecule inhibitors of multidrug-resistance plasmid maintenance using a high-throughput screening approach
Authors: Zulauf Katelyn E. , Kirby James E.
Published: November 2020

Significance

Carbapenem-resistant Enterobacteriaceae (CRE) are multidrug-resistant bacterial pathogens designated as urgent threats by the US Centers for Disease Control and Prevention. Resistance to carbapenems and other antibiotics is usually carried on diverse large, low-copy-number plasmids. Interfering with the replication of such resistance plasmids could potentially restore antibiotic susceptibility. Therefore, we designed a high-throughput screen to identify compounds with anti-CRE plasmid activity. We identified several compounds which by blocking plasmid replication and/or evicting a representative IncFIA CRE plasmid potentiated carbapenem activity, thereby providing proof of principle for our approach. Our findings underscore the potential of antiplasmid therapeutics to restore treatment options for highly drug-resistant pathogens and validate a high-throughput screening approach to identify these agents.
Lipoteichoic acid polymer length is determined by competition between free starter units
Authors: Hesser Anthony R. , Schaefer Kaitlin , Lee Wonsik , Walker Suzanne
Published: November 2020

Significance

Carbohydrate polymers are found in all domains of life, and their biological activities can change depending on their length. Gram-positive bacteria decorate their cell membrane with lipoteichoic acids (LTAs), which are important for essential processes such as cell division, osmotic stability, and antimicrobial resistance. The length of LTA polymers affects fitness, pathogenicity, and susceptibility to beta-lactams. Using in vitro reconstitution, we have identified a unique mechanism that controls polymer length. In addition to providing fundamental mechanistic insight into carbohydrate polymerases, our results provide a platform for studying this conserved cell envelope enzyme and should facilitate the development of antibiotics targeting it.
Increasing risk of another Cape Town “Day Zero” drought in the 21st century
Authors: Pascale Salvatore , Kapnick Sarah B. , Delworth Thomas L. , Cooke William F.
Published: November 2020

Significance

The Cape Town “Day Zero” drought was caused by an exceptional 3-y rainfall deficit. Through the use of a higher-resolution climate model, our analysis further constrains previous work showing that anthropogenic climate change made this event five to six times more likely relative to the early 20th century. Furthermore, we provide a clear and well-supported mechanism for the increase in drought risk in SSA through a dedicated analysis of the circulation response, which highlights how—as in 2015–2017—a reduction in precipitation during the shoulder seasons is likely to be the cause of drought risk in southwestern South Africa in the 21st century. Overall, this study greatly increases our confidence in the projections of a drying SSA.
Structure of the mature kinetoplastids mitoribosome and insights into its large subunit biogenesis
Authors: Soufari Heddy , Waltz Florent , Parrot Camila , Durrieu-Gaillard Stéphanie , Bochler Anthony , Kuhn Lauriane , Sissler Marie , Hashem Yaser
Published: November 2020

Significance

Kinetoplastids is a group of flagellated unicellular eukaryotic parasites including human pathogens, such as
Trypanosoma cruzi
and
Leishmania
spp., etiologic agents of Chagas disease and leishmaniasis. They are potentially lethal, affecting more than 20 million people worldwide. Therapeutic strategies are extremely limited and highly toxic. The finding of new molecular targets represents one venue for the development of new therapeutic strategies. In this work, we present the structure of the full mitoribosomes from two kinetoplastids,
Leishmania tarentolae
and
T. cruzi
, thus far uncharacterized. We also reveal the structure of an large subunit assembly intermediate harboring 16 different factors. In addition to defining a subset of novel kinetoplastid-specific factors, our results shed light on the mitochondrial ribosomal RNA maturation process.
The impact of COVID-19 nonpharmaceutical interventions on the future dynamics of endemic infections
Authors: Baker Rachel E. , Park Sang Woo , Yang Wenchang , Vecchi Gabriel A. , Metcalf C. Jessica E. , Grenfell Bryan T.
Published: November 2020

Significance

Nonpharmaceutical interventions (NPIs), such as social distancing, reduce not only COVID-19 cases but also other circulating infections such as influenza and RSV. The susceptible population for these infections will increase while NPIs are in place. Using models fit to historic cases of RSV and influenza, we project large future outbreaks of both diseases may occur following a period of extended NPIs. These outbreaks, which may reach peak numbers in the winter, could increase the burden to healthcare systems.
Overkill, glacial history, and the extinction of North America’s Ice Age megafauna
Authors: Meltzer David J.
Published: November 2020

The end of the Pleistocene in North America saw the extinction of 38 genera of mostly large mammals. As their disappearance seemingly coincided with the arrival of people in the Americas, their extinction is often attributed to human overkill, notwithstanding a dearth of archaeological evidence of human predation. Moreover, this period saw the extinction of other species, along with significant changes in many surviving taxa, suggesting a broader cause, notably, the ecological upheaval that occurred as Earth shifted from a glacial to an interglacial climate. But, overkill advocates ask, if extinctions were due to climate changes, why did these large mammals survive previous glacial−interglacial transitions, only to vanish at the one when human hunters were present? This question rests on two assumptions: that previous glacial−interglacial transitions were similar to the end of the Pleistocene, and that the large mammal genera survived unchanged over multiple such cycles. Neither is demonstrably correct. Resolving the cause of large mammal extinctions requires greater knowledge of individual species’ histories and their adaptive tolerances, a fuller understanding of how past climatic and ecological changes impacted those animals and their biotic communities, and what changes occurred at the Pleistocene−Holocene boundary that might have led to those genera going extinct at that time. Then we will be able to ascertain whether the sole ecologically significant difference between previous glacial−interglacial transitions and the very last one was a human presence.
REV1 inhibitor JH-RE-06 enhances tumor cell response to chemotherapy by triggering senescence hallmarks
Authors: Chatterjee Nimrat , Whitman Matthew A. , Harris Cynthia A. , Min Sophia M. , Jonas Oliver , Lien Evan C. , Luengo Alba , Vander Heiden Matthew G. , Hong Jiyong , Zhou Pei , Hemann Michael T. , Walker Graham C.
Published: November 2020

Significance

Mutagenic translesion synthesis (TLS) increases cell survival after DNA damage by bypassing lesions that normally block DNA replication but introduces mutations. In cancer cells, REV1/POLζ-dependent mutagenic TLS can contribute to intrinsic chemoresistance, while the mutations it introduces can underlie acquired chemoresistance. Interfering with this TLS pathway genetically or with the small molecule inhibitor JH-RE-06 has been shown to improve cisplatin chemotherapy by suppressing tumor growth and enhancing survival in mouse xenograft tumor models. Cisplatin chemotherapy commonly exerts its antitumor effects via DNA damage-mediated apoptosis. However, in two mouse xenograft models and four mammalian cell lines, the JH-RE-06 unexpectedly profoundly alters the biological response to cisplatin. Apoptosis is suppressed and surprisingly numerous hallmarks of senescence are induced prior to cell death.
The interplay of movement and spatiotemporal variation in transmission degrades pandemic control
Authors: Kortessis Nicholas , Simon Margaret W. , Barfield Michael , Glass Gregory E. , Singer Burton H. , Holt Robert D.
Published: November 2020

Successful public health regimes for COVID-19 push below unity long-term regional
R

t

—the average number of secondary cases caused by an infectious individual. We use a susceptible-infectious-recovered (SIR) model for two coupled populations to make the conceptual point that asynchronous, variable local control, together with movement between populations, elevates long-term regional
R

t

, and cumulative cases, and may even prevent disease eradication that is otherwise possible. For effective pandemic mitigation strategies, it is critical that models encompass both spatiotemporal heterogeneity in transmission and movement.
Master curve of boosted diffusion for 10 catalytic enzymes
Authors: Jee Ah-Young , Tlusty Tsvi , Granick Steve
Published: November 2020

Significance

The literature is inconsistent regarding evidence for boosted molecular mobility during enzyme catalysis, a phenomenon that challenges the common tenet that enzyme mobility is governed solely by Brownian motion. This paper surveys 10 different catalytic enzymes and shows that magnitude of enhanced diffusion scales with energy release rate, the Gibbs free energy of reaction multiplied by the Michaelis–Menten reaction rate. A practical implication is that boosted effective diffusivity can be used to determine the energetics associated with enzyme action, since effective enzyme diffusivity is simply proportional to the change in free energy associated with the biochemical conversion. This master curve to predict the magnitude of boosted molecular mobility may be useful for estimating the effect in as-yet untested enzymes.
Controlling magnetic domain wall velocity by femtosecond laser pulses
Authors: Prabhakara K H , Shapaeva T B , Davydova M D , Zvezdin K A , Zvezdin A K , Davies C S , Kirilyuk A , Rasing Th , Kimel A V
Published: November 2020

Using the technique of double high-speed photography, we find that a femtosecond laser pulse is able to change the velocity of a moving domain wall in an yttrium iron garnet. The change depends on the light intensity and the domain wall velocity itself. To explain the results we propose a model in which the domain wall velocity is controlled by photo-induced generation of vertical Bloch lines.
Comparison of intelligent 4D CT sequence scanning and conventional spiral 4D CT: a first comprehensive phantom study
Authors: Werner René , Szkitsak Juliane , Sentker Thilo , Madesta Frederic , Schwarz Annette , Fernolendt Susanne , Vornehm Marc , Gauer Tobias , Bert Christoph , Hofmann Christian
Published: November 2020

4D CT imaging is a cornerstone of 4D radiotherapy treatment. Clinical 4D CT data are, however, often affected by severe artifacts. The artifacts are mainly caused by breathing irregularity and retrospective correlation of breathing phase information and acquired projection data, which leads to insufficient projection data coverage to allow for proper reconstruction of 4D CT phase images. The recently introduced 4D CT approach i4DCT (intelligent 4D CT sequence scanning) aims to overcome this problem by breathing signal-driven tube control. The present motion phantom study describes the first in-depth evaluation of i4DCT in a real-world scenario. Twenty-eight 4D CT breathing curves of lung and liver tumor patients with pronounced breathing irregularity were selected to program the motion phantom. For every motion pattern, 4D CT imaging was performed with i4DCT and a conventional spiral 4D CT mode. For qualitative evaluation, the reconstructed 4D CT images were presented to clinical experts, who scored image quality. Further quantitative evaluation was based on established image intensity-based artifact metrics to measure (dis)similarity of neighboring image slices. In addition, beam-on and scan times of the scan modes were analyzed. The expert rating revealed a significantly higher image quality for the i4DCT data. The quantitative evaluation further supported the qualitative: While 20% of the slices of the conventional spiral 4D CT images were found to be artifact-affected, the corresponding fraction was only 4% for i4DCT. The beam-on time (surrogate of imaging dose) did not significantly differ between i4DCT and spiral 4D CT. Overall i4DCT scan times (time between first beam-on and last beam-on event, including scan breaks to compensate for breathing irregularity) were, on average, 53% longer compared to spiral CT. Thus, the results underline that i4DCT significantly improves 4D CT image quality compared to standard spiral CT scanning in the case of breathing irregularity during scanning.
Modeling the effect of oxygen on the chemical stage of water radiolysis using GPU-based microscopic Monte Carlo simulations, with an application in FLASH radiotherapy
Authors: Lai Youfang , Jia Xun , Chi Yujie
Published: November 2020

Oxygen plays a critical role in determining the initial DNA damages induced by ionizing radiation. It is important to mechanistically model the oxygen effect in the water radiolysis process. However, due to the computational costs from the many body interaction problem, oxygen is often ignored or treated as a constant continuum radiolysis-scavenger background in the simulations using common microscopic Monte Carlo tools. In this work, we reported our recent progress on the modeling of the chemical stage of the water radiolysis with an explicit consideration of the oxygen effect, based upon our initial development of an open-source graphical processing unit (GPU)-based MC simulation tool, gMicroMC. The inclusion of oxygen mainly reduces the yields of

e

h

and

H

.

chemical radicals, turning them into highly toxic

O
2

.
−

and

H
O

2
.

species. To demonstrate the practical value of gMicroMC in large scale simulation problems, we applied the oxygen-simulation-enabled gMicroMC to compute the yields of chemical radicals under a high instantaneous dose rate

D
˙

i

to study the oxygen depletion hypothesis in FLASH radiotherapy. A decreased oxygen consumption rate (OCR) was found associated with a reduced initial oxygen concentration level due to reduced probabilities of reactions. With respect to dose rate, for the oxygen concentration of 21% and electron energy of 4.5

k
e
V

, OCR remained approximately constant (∼0.22

μ

M

 

G

y

−
1

) for

D
˙

i

’s of

10
6

,

10
7

 

G
y

s

−
1

and reduced to 0.19

μ

M

 

G

y

−
1

at

10
8

 

G
y

s

−
1

, because the increased dose rate improved the mutual reaction frequencies among radicals, hence reducing their reactions with oxygen. We computed the time evolution of oxygen concentration under the FLASH irradiation setups. At the dose rate of

10
7

 

G
y

s

−
1

and initial oxygen concentrations from 0.01% to 21%, the oxygen is unlikely to be fully depleted with an accumulative dose of 30 Gy, which is a typical dose used in FLASH experiments. The computational efficiency of gMicroMC when considering oxygen molecules in the chemical stage was evaluated through benchmark work to GEANT4-DNA with simulating an equivalent number of radicals. With an initial oxygen concentration of 3% (∼105 molecules), a speedup factor of 1228 was achieved for gMicroMC on a single GPU card when comparing with GEANT4-DNA on a single CPU.