bluuebunny/crossref_metadata_2025 huggingface dataset:
Biocolonisation of polymer-modified mortars
Authors: Travailleur Lucy , Gueguen-Minerbe Marielle , Nour Issam , Marceau Sandrine , Keita Emmanuel , Chaussadent Thierry
Published: December 2020

Polymer-modified mortars are cementitious materials that integrate polymers from 5 to 20 wt.%. Those materials are widely used for protecting and/or repairing concrete surfaces among which building facades, civil engineering structures, or sewage networks. In this context, polymer-modified mortars are applied into thin layers of about 1–3 cm. However, previous studies performed regarding such materials were carried out on massive pieces and did not consider the interactions between polymer-modified mortars and microorganisms. Nevertheless, such interactions can lead to undesired aesthetical or structural modifications of those materials. As a result, the main objective of this paper is to evaluate the resistance to biocolonisation of polymer-modified mortars applied into thin layers in environmental conditions that are representative of the on-site applications. Two formulations of polymer-modified mortars and a polymer-free mortar are characterised in the hardened state. Then, the resistance of those mortars to biocolonisation is tested by means of two laboratory accelerated tests. The first experiment is performed in order to recreate biofouling at the surface of the specimens, while the second one exposes the materials to biodeterioration. The results and analyses show that in the presence of polymer, both porosity and capillary absorption of mortars are reduced, but this does not allow preventing or slowing down biocolonisation. In addition, this study suggests that the nature of the polymer has an influence on bioreceptivity of polymer-modified mortars. Finally, our results suggest that in the presence of polymer, the global material may have an improved inner cohesion.
L’apprentissage du raisonnement clinique infirmier dans le cadre d’un dispositif éducatif numérique basé sur la concordance de scripts
Authors: Deschênes Marie-France , Goudreau Johanne
Published: December 2020

Contexte : Un des défis actuels des responsables de la formation des futurs infirmiers est de concevoir des stratégies éducatives pour favoriser le développement optimal du raisonnement clinique infirmier (RCI).But : L’étude visait à développer, mettre à l’essai et évaluer un dispositif éducatif numérique basé sur la concordance de scripts auprès d’étudiants en sciences infirmières. Méthodes : Un devis de recherche-développement a permis de soutenir les étapes de réalisation du dispositif éducatif. Une validation de contenu a été intégrée au devis à l’aide d’une technique Delphi modifiée. Les choix de réponses des étudiants et des experts aux questions du dispositif ont été compilés. Un questionnaire en ligne et des entrevues de groupe focalisées ont été utilisés auprès d’étudiants afin d’évaluer l’acceptabilité et l’utilisabilité du dispositif éducatif. Résultats : Cinq experts-collaborateurs ont validé le contenu du dispositif éducatif. La version finale comptait 81 questions liées à 22 vignettes. Douze experts-panélistes et quarante-cinq étudiants ont répondu aux questions du dispositif éducatif. Les indices alpha (α) de Cronbach ont oscillé entre 0,87 et 0,90. Globalement, les étudiants ont apprécié l’utilisation du dispositif éducatif, dont la rétroaction variée et formative d’experts à des situations apparentées à la vie professionnelle. Conclusion : Le dispositif éducatif repose sur l’utilisation d’un test de concordance de scripts numérisé auquel des rétroactions d’experts sont intégrées à des fins d’apprentissage du RCI. Essentiel, l’engagement des experts-panélistes inscrit la conception d’un tel dispositif éducatif dans une démarche de co-construction et de validation du matériel pédagogique.
Pelvic Lymphadenectomy in Vulvar Cancer – Does it make sense?
Authors: Woelber Linn , Bommert Mareike , Prieske Katharina , Fischer Inger , zu Eulenburg Christine , Vettorazzi Eik , Harter Philipp , Jueckstock Julia , Hilpert Felix , de Gregorio Niko , Iborra Severine , Sehouli Jalid , Ignatov Atanas , Hillemanns Peter , Fuerst Sophie , Strauss Hans-Georg , Baumann Klaus , Beckmann Matthias , Mustea Alexander , Meier Werner , Wimberger Pauline , Hanker Lars , Canzler Ulrich , Fehm Tanja , Luyten Alexander , Hellriegel Martin , Kosse Jens , Heiss Christoph , Hantschmann Peer , Mallmann Peter , Tanner Berno , Pfisterer Jacobus , Mahner Sven , Schmalfeldt Barbara , Jaeger Anna
Published: December 2020

Since the publication of the updated German guideline in 2015, the recommendations for performing pelvic lymphadenectomy (LAE) in patients with vulvar cancer (VSCC) have changed considerably. The guideline recommends surgical lymph node staging in all patients with a higher risk of pelvic lymph node involvement. However, the current data do not allow the population at risk to be clearly defined, therefore, the indication for pelvic lymphadenectomy is still not clear. There are currently two published German patient populations who had pelvic LAE which can be used to investigate both the prognostic effect of histologically verified pelvic lymph node metastasis and the relation between inguinal and pelvic lymph node involvement. A total of 1618 patients with primary FIGO stage ≥ IB VSCC were included in the multicenter AGO CaRE-1 study (1998 – 2008), 70 of whom underwent pelvic LAE. During a retrospective single-center evaluation carried out at the University Medical
Center Hamburg-Eppendorf (UKE), a total of 514 patients with primary VSCC treated between 1996 – 2018 were evaluated, 21 of whom underwent pelvic LAE. In both cohorts, around 80% of the patients who underwent pelvic LAE were inguinally node-positive, with a median number of three affected groin lymph nodes. There were no cases of pelvic lymph node metastasis without inguinal lymph node metastasis in either of the two cohorts. Between 33 – 35% of the inguinal node-positive patients also had pelvic lymph node metastasis; the median number of affected groin lymph nodes in these patients was high (> 4), and the maximum median diameter of the largest inguinal metastasis was > 40 mm in both cohorts. Pelvic lymph node staging and pelvic radiotherapy is therefore probably not necessary for the majority of node-positive patients with VSCC, as the relevant risk of pelvic lymph node involvement was primarily found in node-positive patients with high-grade disease. More,
ideally prospective data collections are necessary to validate the relation between inguinal and pelvic lymph node involvement.
Vitamin A (Retinol): Stiefkind der Ernährungsmedizin
Authors: Gröber Uwe
Published: December 2020

Wer kennt es nicht, das Bild der Karotte – symbolisch für die wichtige Vitamin-A-Zufuhr. Vitamin A spielt vor allem bei der Entwicklung des Gehirns und der Sehfähigkeit eine zentrale Rolle. Leider existiert auch in der heutigen Zeit immer noch das Problem, dass die Empfehlungen für eine bedarfsgerechte Vitamin-A-Zufuhr über die Ernährung nicht erreicht werden – mindestens 25 % der Bevölkerung leiden unter Vitamin-A-Mangel. Zu den Risikogruppen gehören insbesondere Kleinkinder, Schwangere und Stillende. Der Mangel kann zu erheblichen Beeinträchtigungen und Erkrankungen führen. Mittlerweile zeigen aktuelle Daten, dass die Bildung von Vitamin A aus Carotinoiden jedoch überschätzt wurde, d. h. die Fachgesellschaften sollten ihre Empfehlungen anpassen. Des Weiteren geht der Beitrag auf Vitamin A als Behandlungsoption bei COVID-19 ein.
Die Lebenszeitprävalenz von Schuldgefühlen in der deutschen Erwachsenenbevölkerung – Ergebnisse einer bundesweiten telefonischen Bevölkerungsbefragung
Authors: Luck Tobias , Luck-Sikorski Claudia
Published: December 2020

Ziel Bestimmung der Lebenszeitprävalenz von Schuldgefühlen in der deutschen Erwachsenenbevölkerung basierend auf den Daten einer bundesweiten telefonischen Bevölkerungsbefragung (n = 1003; 18+ Jahre; Mai–Juni 2019).

Methodik Berechnung gewichteter Prävalenzraten mit Konfidenzintervallen (95 %-KI) und Untersuchung des Zusammenhangs mit Kofaktoren anhand multivariabler logistischer Regressionsanalysen.

Ergebnisse Die ermittelte Lebenszeitprävalenz empfundener Schuldgefühle beträgt 68,5 % (95 %-KI = 65,6–71,3). Jüngeres Alter, höhere Bildung und aktuelle depressive Symptomatik waren mit höheren Prävalenzraten assoziiert. Kein Zusammenhang zeigte sich für Geschlecht und majore Depression.

Schlussfolgerung Ein substanzieller Anteil der deutschen Erwachsenenbevölkerung hat schon einmal Schuldgefühle empfunden. Weiterer Forschungsbedarf besteht v. a. zu der Frage, inwieweit Schuldgefühle zu einem erhöhten Depressionsrisiko beitragen und nicht nur als Kriterium für die Störung anzusehen sind.
Rückkehr an den Arbeitsplatz nach psychischer Erkrankung – Ein Scoping Review
Authors: Blank Daniela , Brieger Peter , Hamann Johannes
Published: December 2020

Hintergrund Erwerbstätige mit einer psychischen Erkrankung haben nach einer psychischen Krise oft massive Schwierigkeiten, ihre Arbeit wiederaufzunehmen. Ziel des Reviews ist, einen internationalen Überblick über Return-to-Work (RTW)-Interventionen zu geben.

Methode Es wurde eine systematische Literaturrecherche durchgeführt.

Ergebnisse 88 Artikel wurden gesichtet und 29 Studien eingeschlossen. Die untersuchten RTW-Interventionen setzen an 3 Punkten an: 1) Individuum, 2) Arbeitsumfeld und 3) Versorgungsstruktur. Für den überwiegenden Teil zeigt sich, dass die Maßnahmen eine positive Wirkung erzielen.

Schlussfolgerungen Obgleich nicht alle Interventionen auf den deutschen Kontext übertragen werden können, so geben sie wichtige Hinweise, wie ein Unterstützungsangebot an der Schnittstelle zwischen Gesundheitssystem und Arbeit gestaltet werden kann.
Straightforward Synthesis of Succinimide-Fused Pyrrolizidines by A Three-Component Reaction of α-Diketone, Amino Acid, and Maleimide
Authors: Zhao Hua , Zhai Hongbin , Shen Peng , Guo Yeting , Wei Jian , Zhao Yufen
Published: December 2020

An efficient, one-pot, three-component [3+2] cycloaddition reaction of azomethine ylide obtained from α-dicarbonyl compounds (cyclic and acyclic diketone or keto ester) and amino acids with maleimides under catalyst-free conditions has been developed. This cascade protocol shows high efficiency and remarkable functional group tolerance, and the ubiquitous succinimide-fused pyrrolizidines with a highly compact and strained scaffold were obtained with high yield and excellent diastereoselectivity. Furthermore, this novel and atom-economical strategy could be performed on a gram scale with comparable reaction efficiency.
Pediatric Malignant Glomus Tumor of the Cervical Paraspinal Tissue: Case Report and Review of the Literature
Authors: Ziegler Andrea , Thorpe Eric
Published: December 2020

Glomus tumors are mesenchymal tumors that arise from glomus bodies and most frequently occur in the distal extremities. These tumors can occur throughout the body and are typically benign. However, a very small fraction of glomus tumors displays aggressive features and are considered atypical or malignant. We report on our experience and management of the first case in the literature of a malignant glomus tumor in a child originating in the paraspinal region with involvement of the cervical spine. Malignant glomus tumors tend to be locally aggressive, and en bloc resection is difficult, especially when the tumors occur in the head and neck. Additional studies on disease progression and adjuvant treatment outcomes are necessary to determine the best treatment approach and long-term outcomes in patients with malignant glomus tumors.
Diagnosis and Management of a Large Adrenal Myelolipoma
Authors: Ghantous Imad , Saad Melissa Kyriakos , Saber Toufic , Mahfouz Elissa , Matta Imad , Saikaly Elias
Published: December 2020

Adrenal myelolipoma is a rare condition. Although benign in nature, these tumors can increase in size and cause a mass effect to nearby structures presenting as abdominal distension and pain. In 90% of cases, adrenal myelolipomas are unilateral. However, the real challenge in management is when bilateral adrenal myelolipoma is present. Herein, we present a case of a 51-year-old male Caucasian patient with bilateral adrenal myelolipoma. The patient had a large left adrenal myelolipoma (23 × 13 cm) and a small one on the right (4.4 × 4 cm). We opted for an open left adrenalectomy due to classical features on computed tomography scan and the mass effect of the tumor.
Squandering the territorial capital in the Balkans? Urban megaprojects between global trends and local incentives
Authors: Peric Ana , D’hondt Frank
Published: December 2020

Throughout its history, but also squeezed between the current challenges of globalisation and sovereignty, the Balkans has been confronted with a number of different political, economic, environmental, and cultural problems. Such a complex social framework inevitably implies spatial degradation, not only in terms of the urban forms as the final planning product, but also in terms of the nature of the planning process and urban governance. Notably, we assume that territorial capital in the Balkans is under serious threat due to the abuse of legal procedures, the neglect of the public interest and the politicisation of planning. To elucidate this, we focus on the megaprojects Belgrade Waterfront (Belgrade) and Hellinikon (Athens) as examples of urban development that require exceptional conditions such as special regulations, additional funding, long-term timeframes, and ad hoc actor networks. Against the conceptual background of multi-level governance and based on in-depth case studies, we examine the nature of vertical cooperation between authorities at different levels (from supranational to local), horizontal cooperation amongst different stakeholders, and the role of planning professionals who are seen as facilitators in this process. Finally, we point out to the most important conditions that enable a democratic social, political and professional framework for urban megaprojects.
Multiprobe scanning probe microscope using a probe-array head
Authors: Sun Fengming , Zhu Zhenyu , Ma Long
Published: December 2020

We have developed a microelectromechanical system (MEMS)-based multiprobe scanning probe microscope (SPM) to improve imaging efficiency. The SPM head contains seven identical MEMS probes, and each of them integrates a displacement sensor and a Z-axis actuator. Force constant mode is designed based on the force feedback strategy rather than on the position feedback strategy for this kind of SPM head. A nano-measuring machine is equipped with the lateral XY scanners, which can reach a motion range of 25 mm × 25 mm. After calibration, the measurement of one-dimensional grating has been made to demonstrate the capability of multiprobe scanning.
Improved clustering and deep learning based short-term wind energy forecasting in large-scale wind farms
Authors: Huang Yu , Li Jiayu , Hou Weizhen , Zhang Bingzhe , Zhang Yan , Li Yongling , Sun Li
Published: December 2020

As a promising renewable solution for sustainable power generation worldwide, wind energy is receiving continuing attention from both industry and the academic community. However, the randomness and intermittency of wind energy will affect the stable operation and stability of the power system and further affect the economic benefits of the power grid. What makes the matter worse is the inevitable coupling between each pair of wind turbines in the large-scale wind farm. Besides, the resolution of prediction is severely limited by the spatial scale of wind farms. These problems bring great difficulties for the control and scheduling of wind farms. To this end, this paper proposes a novel wind speed prediction method for wind farms by borrowing some wisdom from machine learning methods. First, density peak clustering (DPC) is employed to separate the tremendous number of scattered wind turbines into a much significantly reduced number of groups, the wind turbines in each of which are treated as a unity. Based on the priority setting of each indicator in clustering, the data are preprocessed with different weightings. Principal component analysis is utilized to avoid DPC's poor clustering effects in case the dataset is high-dimensional. Finally, by considering simultaneous effects from historical and present data, long short-term memory based deep learning neural networks are trained and used to iteratively predict the potential of the wind energy in each unit for each time slot. The effectiveness of the proposed algorithm is verified by taking an in-service wind farm in China as an example.
Design and development of high power RF amplifier for 88 in. room temperature cyclotron at Variable Energy Cyclotron Centre (VECC), Kolkata
Authors: Ghosh Surajit , Mandal Aditya , Seth Sudeshna , Manna S. K. , Panda U. S. , Som Sumit
Published: December 2020

A tetrode based high power radio frequency (RF) amplifier has been designed, developed, and commissioned at Variable Energy Cyclotron Centre, Kolkata, India, for the 88-in. room temperature K130 cyclotron. The amplifier feeds power to a RF cavity based on the quarter-wave cantilever-type resonating structure to develop a high accelerating voltage for particle acceleration. The initial design of this amplifier was based on tetrode tube, which has already become obsolete. A new design of the RF amplifier has been made with a different tetrode of much lower power to satisfy the requirement of the cyclotron. This paper gives detailed insight into the various issues of the tetrode amplifier design and operational experience for the K130 cyclotron RF system.
Measurement of the breathing mode oscillations in Hall thruster plasmas with a fast-diving triple Langmuir probe
Authors: Giannetti V. , Saravia M. M. , Andreussi T.
Published: December 2020

We developed a novel measurement apparatus and data processing technique that allow for the quantitative reconstruction of the effects of breathing mode oscillations on the main properties of the plasma in Hall thrusters. The approach is based on the use of a triple Langmuir probe mounted on a rapidly moving arm to scan the channel centerline and was validated in an experimental campaign on a 5 kW-class Hall thruster. The probe data were sampled at high frequency during its motion, and a Bayesian methodology was used to reliably infer the plasma properties from the instantaneous voltage and current measurements. In order to model the interaction of the electrodes with the plasma, a parameterization of the Laframboise sheath solution was used. Data were collected continuously during the probe motion from the plume up to the near-anode region of the thruster, allowing for the reconstruction of the salient features of the plasma oscillations as a function of axial location. A time–frequency analysis of the measured plasma properties based on wavelets was then performed to gain insight into the evolution and phase shift of the oscillations over the investigated plasma domain. The developed diagnostic method can provide quantitative information on the instantaneous value of plasma density, electron temperature, and plasma potential along the thruster centerline with good spatial resolution and has proved to be a valid approach to investigate breathing mode oscillations in Hall thruster plasmas.
Phase-change Janus particles with switchable dual properties
Authors: Soma Ryo , Nakayama Bokusui , Kuwahara Masashi , Yamamoto Eiji , Saiki Toshiharu
Published: December 2020

We developed switchable Janus particles (JPs) fabricated by coating one hemisphere of silica microspheres with a phase-change film. We used the chalcogenide GeSbTe (GST), which exhibits a reversible phase change between a metal-like crystalline phase (c-GST) and a dielectric-like amorphous phase (a-GST). As a driving force for self-propelling the JPs, a perpendicular alternating current electric field was applied; the frequency dependence of the motion of an individual JP and that of inter-JP interaction were investigated. At lower frequencies (2–20 kHz), a-GST JPs were propelled with their silica side facing forward, which is similar to the behavior of Au–silica JPs propelled by the well-known induced-charge electrophoresis mechanism, whereas c-GST JPs were immobile because they adhered to the indium tin oxide substrate. At higher frequencies (50–300 kHz), both a-GST and c-GST JPs were propelled with their GST side facing forward and a substantial difference in inter-JP interaction was observed: repulsive collision for c-GST JPs but attractive stacking for a-GST JPs.
Reflectin needs its intensity amplifier: Realizing the potential of tunable structural biophotonics
Authors: Morse Daniel E. , Taxon Esther
Published: December 2020

Underwater camouflage and communication in a family of recently evolved squids are controlled, in part, by the reflectin proteins, which regulate dynamic changes in the color and intensity of light reflected from intracellular Bragg reflectors and Mie scatterers. The reflectins act as a signal transducer, precisely tuning the dimensions and refractive index of the membrane-bounded structural reflectors containing them to an extent exactly proportional to neuronal signaling. This calibration between the activating signal and the output color and intensity of reflectance is governed by the physics of the liquid state of reflectin assemblies, which osmotically fine-tune the dimensions and refractive index of the membrane-bounded structural reflectors containing them. While thin-film or genetically engineered assemblies of reflectin deliver changes in the colors of reflection approximating those of the biological system (as do other proteins and polymers), none has delivered the signal-activated increase in the intensity of reflectance characteristic of the native system. The membrane envelopes (Bragg reflector lamellae and Mie-scattering vesicles) containing the reflectins apparently serve as amplifiers, functionally “impedance matched” to the range of tunable sizes of the reflectin assemblies; reflectin films or assemblies lacking such an amplifier fail to deliver signal-activated increases in reflectance intensity.
Achieving high-speed rotations with a semi-flexible rotor driven by ultralow-frequency vibrations
Authors: Fan Kangqi , Liang Geng , Wei Danmei , Wang Weidong , Zhou Shengxi , Tang Lihua
Published: December 2020

Rotational motions are generally enabled by the flow energy for generating electricity or by the electric energy to drive various mechanical motions. Here, we report a fundamentally different approach (which we name “semi-flexible rotor”) that uses omnipresent ultralow-frequency (<5 Hz) vibrations as the energy source to achieve high-speed rotational motions. The semi-flexible rotor comprises mainly a turntable, an elastic support, a lid, and a piece of rope, in which the periodically tensioned and released rope under external excitations provides the torque for spinning the turntable. The feasibility of the proposed approach is confirmed by both experimental measurements and theoretical simulations. As excited by a quasi-harmonic vibration with an amplitude of 10 mm, the rotor achieves a high rotational speed of up to 250 rad/s (2400 rpm) at around 2 Hz, and can provide an average rotational speed higher than 50 rad/s within a frequency range from 0.5 Hz to 5 Hz. The semi-flexible rotor is thus an option for realizing some rotation-based devices (e.g., miniature centrifuges) that work in scenarios without electricity supply or for designing efficient energy harvesters that exploit ubiquitous ultralow-frequency vibrations to generate electricity.
To study the surface modified cobalt zinc ferrite nanoparticles for application to magnetic hyperthermia
Authors: Halder Suman , Liba S. I. , Nahar A. , Sikder S. S. , Hoque S. Manjura
Published: December 2020

In the present work, we have studied the influence of the annealing temperature and concentration of Co0.5Zn0.5Fe2O4 nanoparticles as a heat generation material for hyperthermia therapy. Cobalt zinc ferrite (Co0.5Zn0.5Fe2O4) nanoparticles were synthesized by the chemical co-perception method and annealed at 200 °C, 400 °C, and 600 °C for 3 h. The structural characterization was carried out using an x-ray diffractometer, and all samples exhibit a single-phase spinel structure. The M-H loop of the as-dried and annealed samples revealed a narrow “S” shaped hysteresis cycle, which exhibits the superparamagnetic behavior of all samples. The Mössbauer spectrum of all samples at room temperature showed a doublet, which is the signature of the superparamagnetic nature, and it is in good agreement with the acquired M-H curves. Surface modifications of the as-dried and annealed nanoparticles were achieved by coating the nanoparticles with chitosan, and solutions of different concentrations (1 mg/ml, 2 mg/ml, 4 mg/ml, and 6 mg/ml) were prepared. Employing dynamic light scattering measurement, the hydrodynamic diameter of the chitosan-coated nanoparticles at 37 °C was found to be between 173 nm and 231 nm, and the polydispersity index was less than 0.30 for all concentrations. The induction heating measurements indicated that the heating efficiency of chitosan-coated nanoparticles increased according to the order of annealing temperature (600 °C > 400 °C > 200 °C> as-dried) and the solution of concentration (6 mg/ml > 4 mg/ml > 2 mg/ml > 1 mg/ml).
Origin of performance improvement in solution-processed indium–gallium–zinc-oxide thin-film transistors having thin active layer and asymmetric dual gate structure
Authors: Kim Jeongmin , Jeong Jaewook
Published: December 2020

In this paper, we report the electrical characteristics of thin active layer indium–gallium–zinc-oxide thin-film transistors (IGZO TFTs) having an asymmetric dual gate structure. It was observed that the performance of IGZO TFTs significantly improved when the TFT is operated in the dual gate mode though the performance of the top gate mode shows very poor performance of low field-effect mobility and large subthreshold slope. We found that the channel electrons are coupled in the bulk region when the active layer is very thin, and top gate biasing provides additional electrons to the coupled channel region, which improves the electrical performance of dual gate mode IGZO TFTs. Bias stress instability measurements also indicate that dual gate mode IGZO TFTs show better stability compared to the other mode because coupled electrons are mainly formed in the bulk region, which reduce the effect of interfacial defect density of states. Therefore, the improvements of performance of dual gate electrode IGZO TFTs can be realized regardless of the relatively poor performance of the top gate mode.
Testing the quantization of electromagnetic field in a quarter-wavelength transmission line resonator by traveling-wave scattering measurements
Authors: Gao Haiyan , Zhai Donghai , Gao Jiansong , Wei Lianfu
Published: December 2020

A half-wavelength cavity, wherein the electromagnetic field is quantized as standing-wave photons, is a typical artificial quantum system that has widely been used to implement quantum information processing. In this paper, we propose an approach to confirm the quantization of the electromagnetic field in another type of cavity, namely, a quarter-wavelength transmission line resonator (TLR), by using traveling-photon scattering measurements. Furthermore, we show that the number of photons in a TLR can be destructively detected by using the usual IQ-mixed technique. We hope that quarter-wavelength TLRs may also serve as quantum devices to implement on-chip solid-state quantum information processing.
First-principles description of electrocatalytic characteristics of graphene-like materials
Authors: Hartmann Gregory , Hwang Gyeong S.
Published: December 2020

Graphene-like materials (GLMs) have received much attention as a potential alternative to precious metal-based electrocatalysts. However, the description of their electrocatalytic characteristics may still need to be improved, especially under constant chemical potential. Unlike the case of conventional metal electrodes, the potential drop across the electrical double layer (ϕD) at the electrode–electrolyte interface can deviate substantially from the applied voltage (ϕapp) due to a shift of the Dirac point (eϕG) with charging. This may in turn significantly alter the interfacial capacitance (CT) and the relationship between ϕapp and free-energy change (ΔF). Hence, accurate evaluation of the electrode contribution is necessary to better understand and optimize the electrocatalytic properties of GLMs. In this work, we revisit and compare first-principles methods available to describe the ϕapp–∆F relation. Grand-canonical density functional theory is used to determine ΔF as a function of ϕapp or electrode potential (ϕq), from which the relative contribution of eϕG is estimated. In parallel, eϕG is directly extracted from a density functional theory analysis of the electronic structure of uncharged GLMs. The results of both methods are found to be in close agreement for pristine graphene, but their predictions deviate noticeably in the presence of adsorbates; the origin of the discrepancy is analyzed and explained. We then evaluate the application of the first-principle methods to prediction of the electrocatalytic processes, taking the reduction (hydrogenation) and oxidation (hydroxylation) reactions on pristine graphene as examples. Our work highlights the vital role of the modification of the electrode electronic structure in determining the electrocatalytic performance of GLMs.
Excellent thermoelectric performance of open framework Si24 nanowires from density functional based tight-binding calculation
Authors: Huang Weiqiang , Ouyang Tao , Tang Chao , He Chaoyu , Li Jin , Zhang Chunxiao , Zhong Jianxin
Published: December 2020

Open framework Si24 is a cage-like silicon allotrope with a highly anisotropic character and predicted to possess fascinating optoelectronic and thermoelectric performance. In this paper, we systematically investigated the thermoelectric conversion performance of Si24 nanowires (Si24NWs) through using nonequilibrium Green's function method as implemented in the density functional based tight-binding framework. The calculations reveal that Si24NWs possess superb electronic transport properties, e.g., the Seebeck coefficient could approach 2.67 mV/k at room temperature (several times greater than that of diamond silicon nanowires). Meanwhile, evident anisotropic thermal transport is also observed in Si24NWs, where the room temperature phonon thermal conductance of Si24NW-[100]/[010]/[001] is 1.36/0.27/0.38 nW/k, respectively. Through analyzing the phonon spectra of Si24NWs, we explain the origin of such an anisotropic thermal transport property. By combining the electron and phonon transport properties, the thermoelectric properties of Si24NWs are predicted and the ZT value of Si24NW-[100]/[010]/[001] could, respectively, approach 0.18/1.28/0.85 at room temperature. In order to achieve better thermoelectric performance, the Si/Ge core–shell structures are constructed (based on Si24NW-[010]). The results show that the core–shell structure is indeed a viable and efficient way to improve the thermoelectric conversion efficiency (the figure of merit could be boosted to 2.2 at room temperature). The findings presented in this paper shed light on the thermoelectric performance of Si24NWs and could provide a helpful guideline for designing and fabricating excellent thermoelectric devices based on Si24NWs.
Nitrogen vacancies and carrier-concentration control in rare-earth nitrides
Authors: Holmes-Hewett W. F. , Pot C. , Buckley R. G. , Koo A. , Ruck B. J. , Natali F. , Shaib A. , Miller J. D. , Trodahl H. J.
Published: December 2020

Most members of the ferromagnetic rare-earth nitride series display doping control over electron transport, with nitrogen vacancies being the most common donor. This paper reports the control and characterization of vacancies in one of the fourteen in the series, DyN. Electrical transport and optical spectra in films with controlled concentrations of vacancies show a pair of in-gap impurity levels ∼ 0.4 eV below the conduction band minimum and a third impurity level that lies nearly coincident with the conduction band minimum. Electron transport is found to be activated for concentrations ≤1019 cm−3, with signatures of extended state conduction at the Fermi level for higher concentrations.
What influences trainee decisions to practise in rural and regional Australia?
Authors: Seal Alexa , Harding Catherine , McGirr Joe
Published: December 2020

Although international medical graduates (IMGs) make up a substantial part of the Australian rural general practice workforce, most research on factors associated with rural practice has focused on Australian medical graduates (AMGs). This study aimed to determine whether there were differences between IMGs and AMGs in terms of these factors. Registrars in training and recent fellows (Fellowship of the Royal Australian College of General Practitioners/Fellowship of the Australian College of Rural and Remote Medicine) who participated in training in rural and regional Australia were surveyed about practice models and rural practice. Almost two-thirds of participants were practicing or intending to practice in rural areas, with no difference between AMGs and IMGs. None of the variables associated with rural practice for AMGs was found to be associated with rural practice in IMGs in univariate binary regression analysis. Two key variables that are strongly associated with rural medical practice in the current literature, namely rural background and rural exposure, were not significant predictors of rural practice among IMGs. Due to the significant number of IMGs in regional training programs, any future incentives designed to improve rural recruitment and retention need to address factors relevant to IMGs.
Polyphosphate is an extracellular signal that can facilitate bacterial survival in eukaryotic cells
Authors: Rijal Ramesh , Cadena Louis A. , Smith Morgan R. , Carr Joseph F. , Gomer Richard H.
Published: December 2020

Significance

Macrophages use phagocytosis to engulf bacteria such as
E. coli
and kill them. Pathogenic bacteria such as
Mycobacterium tuberculosis
are similarly ingested, but not killed, by macrophages. We find that
M. smegmatis and M. tuberculosis
bacteria accumulate high levels of extracellular polyphosphate compared to
E. coli
and survive better after phagocytosis in
Dictyostelium discoideum
or macrophages. The addition of polyphosphate causes some
D. discoideum
or macrophages to keep ingested nonpathogenic
E. coli
bacteria alive. Conversely, exopolyphosphatase, an enzyme that degrades polyphosphate, causes
D. discoideum
and macrophages to kill more of the ingested bacteria. Polyphosphate inhibits phagosome acidification and lysosome activity in
D. discoideum
and macrophages, suggesting that extracellular or intraphagosomal polyphosphate activates a pathway to potentiate viability of ingested bacteria.
Genome analyses reveal the hybrid origin of the staple crop white Guinea yam (
Dioscorea rotundata
)
Authors: Sugihara Yu , Darkwa Kwabena , Yaegashi Hiroki , Natsume Satoshi , Shimizu Motoki , Abe Akira , Hirabuchi Akiko , Ito Kazue , Oikawa Kaori , Tamiru-Oli Muluneh , Ohta Atsushi , Matsumoto Ryo , Agre Paterne , De Koeyer David , Pachakkil Babil , Yamanaka Shinsuke , Muranaka Satoru , Takagi Hiroko , White Ben , Asiedu Robert , Innan Hideki , Asfaw Asrat , Adebola Patrick , Terauchi Ryohei
Published: December 2020

Significance

Guinea yam is an important staple tuber crop in West Africa, where it contributes to the sustenance and sociocultural lives of millions of people. Understanding the genetic diversity of Guinea yam and its relationships with wild relatives is important for improving this important crop using genomic information. A recent genomics study proposed that Guinea yam originated from a wild relative, the rainforest species
Dioscorea praehensilis
. Our results based on sequencing of 336 Guinea yam accessions do not support this notion; rather, our results indicate a hybrid origin of
Dioscorea rotundata
from crosses between the savannah species
Dioscorea abyssinica
and
D. praehensilis.
A flexible monolithic integrated silicon low noise amplifier on plastic substrate
Authors: You Zixuan , Liu Hao , Xu Yanmeng , Ma Zhenqiang , Qin Guoxuan
Published: December 2020

Flexible radio frequency (RF) circuits are highly desirable for flexible communication and other miniaturized function modules. However, the prevalent studies on flexible high-speed electronics have mostly focused on individual elements such as transistors, inductors, capacitors and transmission lines. Research on flexible RF monolithic integrated functional circuits is still limited. This letter presents the design of a flexible monolithic integrated silicon RF low noise amplifier (LNA) on plastic substrate. For the LNA, a flexible thin film transistor (TFT) based on a silicon nanomembrane, high-frequency flexible inductors and capacitors are fabricated and modeled. The impedance matching circuit on plastic substrate is analyzed and optimized. The LNA has a gain of ∼11 dB and a noise figure (NF) of ∼4.3 dB at 300 MHz. The influence of the parasitics induced by the flexible impedance matching on the gain and NF is discussed. This study provides useful design guideline for flexible RF monolithic integrated circuits and expands the high frequency applications of flexible electronics.
Enhancement of electrical properties of solution-processed oxide thin film transistors using ZrO2 gate dielectrics deposited by an oxygen-doped solution
Authors: Luo Chunlai , Huang Ting , Li Changhao , Zhang Yan , Zou Zhengmiao , Li Yushan , Tao Ruiqiang , Gao Jinwei , Zhou Guofu , Lu Xubing , Liu Jun-Ming
Published: December 2020

Solution deposition of high-quality dielectric films is one of the big challenges in achieving excellent electrical performance of bi-layer solution-processed metal oxide (MO) thin film transistors (TFTs). Using an oxygen-doped precursor solution (ODS), we successfully deposited high-quality zirconium oxide (ZrO2) dielectric films by a solution process. The ODS-ZrO2 films show low leakage current density (10−7 A cm−2 at 2 MV cm−1), high breakdown electric field (7.0 MV cm−1) and high permittivity (19.5). Consequently, solution-processed indium oxide (In2O3) TFTs with ODS-ZrO2 film as the gate dielectric show excellent electrical performance, for example high carrier mobility up to 62.02 cm2 V s−1, a large on/off drain current ratio of 3.0 × 106, a small subthreshold swing of 0.14 V and excellent bias stress stability. Our work demonstrates the critical role of the dielectric film in the electrical performance of MO-TFTs. More importantly, we reveal that high dielectric constant (κ) dielectric film deposited with ODS should be an effective way to significantly increase the electrical properties of MO-TFTs for future low-cost, high-performance applications.
Computational compound screening of biomolecules and soft materials by molecular simulations
Authors: Bereau Tristan
Published: December 2020

Decades of hardware, methodological, and algorithmic development have propelled molecular dynamics (MD) simulations to the forefront of materials-modeling techniques, bridging the gap between electronic-structure theory and continuum methods. The physics-based approach makes MD appropriate to study emergent phenomena, but simultaneously incurs significant computational investment. This topical review explores the use of MD outside the scope of individual systems, but rather considering many compounds. Such an in silico screening approach makes MD amenable to establishing coveted structure-property relationships. We specifically focus on biomolecules and soft materials, characterized by the significant role of entropic contributions and heterogeneous systems and scales. An account of the state of the art for the implementation of an MD-based screening paradigm is described, including automated force-field parametrization, system preparation, and efficient sampling across both conformation and composition. Emphasis is placed on machine-learning methods to enable MD-based screening. The resulting framework enables the generation of compound-property databases and the use of advanced statistical modeling to gather insight. The review further summarizes a number of relevant applications.
Multiple nano-filaments based efficient resistive switching in TiO2 nanotubes array influenced by thermally induced self-doping and anatase to rutile phase transformation
Authors: Hazra Arnab , Tripathi Ashutosh , Jan Atif , Kundu Souvik , Boppidi Pavan Kumar Reddy
Published: December 2020

In this paper, the impact of thermally induced self-doping and phase transformation in TiO2 based resistive random-access memory (ReRAM) is discussed. Instead of a thin film, a vertically aligned one-dimensional TiO2 nanotube array (TNTA) was used as a switching element. Anodic oxidation method was employed to synthesize TNTA, which was thermally treated in the air at 350 °C followed by further annealing from 350 °C to 650 °C in argon. Au/TiO2 nanotube/Ti resistive switching devices were fabricated with porous gold (Au) top electrode. The x-ray diffraction results along with Raman spectra evidently demonstrate a change in phase of crystallinity from anatase to rutile, whereas photoluminescence spectra revealed the self-doping level in terms of oxygen vacancies (OV) and Ti interstitials (Tii) as the temperature of thermal treatment gets increased. The electrical characterizations establish the bipolar and electroforming free resistive switching in all the samples. Among those, the ReRAM sample S3 thermally treated at 550 °C displayed the most effective resistive switching properties with R
OFF/R
ON of 102 at a read voltage of −0.6 V and a SET voltage of −2.0 V. Moreover, the S3 sample showed excellent retention performance for over 106 s, where stable R
OFF/R
ON ≈ 107 was maintained throughout the experiment.
Combined effects of surface plasmon coupling and Förster resonance energy transfer on the light color conversion behaviors of colloidal quantum dots on an InGaN/GaN quantum-well nanodisk structure
Authors: Chen Yen-Po , Ni Chia-Chun , Wu Ruei-Nan , Kuo Sheng-Yang , Su Yu-Cheng , Huang Yang-Yi , Chen Jia-Wei , Hsu Yi-Chiao , Wu Shung-Hsiang , Chen Chien-Yu , Wu Ping-Hsiu , Kiang Yean-Woei , Yang C C
Published: December 2020

By forming nanodisk (ND) structures on a blue-emitting InGaN/GaN quantum-well (QW) template, the QWs become close to the red-emitting quantum dots (QDs) and Ag nanoparticles (NPs) attached onto the sidewalls of the NDs such that Förster resonance energy transfer (FRET) and surface plasmon (SP) coupling can occur to enhance the efficiency of blue-to-red color conversion. With a larger ND height, more QWs are exposed to open air on the sidewall for more QD/Ag NP attachment through QD self-assembly and Ag NP drop casting such that the FRET and SP coupling effects, and hence the color conversion efficiency can be enhanced. A stronger FRET process leads to a longer QD photoluminescence (PL) decay time and a shorter QW PL decay time. It is shown that SP coupling can enhance the FRET efficiency.
Electromagnetic properties of the Pc
(4312) pentaquark state
Authors: Özdem Ulaş
Published: December 2020

Using the light-cone QCD sum rules, we evaluate the magnetic moment of the

pentaquark state by considering both the

molecular and diquark-diquark-antiquark state, with quantum numbers

. In the calculations, we use the diquark-diquark-antiquark and molecular form of the interpolating currents for the

pentaquark and the distribution amplitudes of the photon. The numerical results for the magnetic moment obtained using the two different pictures are quite different from each other, which can be used to pin down the underlying structure of

. Any experimental measurement of the magnetic moment in the near future will provide an understanding of the internal structure of this pentaquark state.
XIV International Congress of Electronics and Advanced Technologies
Authors: Pardo García A , Dueñas Ramírez L M , V-Niño E D
Published: December 2020

The Universidad de Pamplona, Colombia, through its Faculty of Engineering and Architecture, realized the XIV International Congress of Engineering “Electronics and Advanced Technologies” (XIV CIETA), X International Congress on Systems, Informatics, and Knowledge Engineering (CICOM), X International Congress on Telecommunications, IX International Congress on Electrical Engineering, V International Congress of Mechatronics Engineering and II International Congress of Industrial Engineering, Virtual modality in Pamplona, Norte de Santander, Colombia, on October 28, 29 and 30 of the year 2020.

This International Congress “Electronics and Advanced Technologies” is a point of contact between the college students, engineers and researchers as much from the Universidad de Pamplona as from other foreign Universities or of Colombia. The International Congress “Electronics and Advanced Technologies” proposes general and specialized articles and discusses topics such as Physics, Mathematics, Automatic Control, Automatization, Digital signal Processing, Electronics, Electrical treat, Telecommunications, Systems, and areas related to sciences and engineering.

List of Organizing Committee, International Scientific Committee, National Scientific Committee, Local Scientific Committee, Logistics Committee, Sponsor and Partners are available in this pdf.
Mesoporous NiCo2O4 nanoparticles as cathode additive for high-performance lithium sulfur battery
Authors: Abualela Salma , Lv Xiaoxue , Hu Yin , Abd-Alla Mubarak Dirar , Ewakeel Sohad. S. , Mohamed Adam Khalifa
Published: December 2020

Lithium sulfur batteries with high theoretical energy density are promising candidate as next-generation energy storage system. However, practical strategies for releasing the true potential of sulfur cathode are still needed. Therefore, in this work, the NiCo2O4 with hybrid nanostructure is manufactured in a simple atmospheric and water-based method. The surface area of the mesoporous NiCo2O4 is determined to be about 59.99 m2g−1. The electrode with NiCo2O4 exhibits a high initial capacity of 1399.8 mAh g−1 at the current density of 0.1 C. These results indicate that the electrode material has enormous potential as high-performance cathode materials.
Deep residual network for enhanced fault diagnosis of rotating machinery
Authors: Xiong Shoucong , Shi Tielin
Published: December 2020

Deep residual network (DRN) is a recently-developed powerful algorithm in the deep learning filed. This paper introduces the superiority of DRN into the fault diagnosis of rotating machinery for simplifying traditional diagnosing process as well as enhancing predicting performance. DRN can not only extract features automatically from raw or processed signals but also benefit from its especially deep architecture to continually improve representation capacity without worrying gradient divergence issues. The functions of DRN result from the unique structure design called residual building block, which will be described clearly with the network overall architecture in this paper. Additionally, the comparison of the DRN with other machine learning-based and neural network-based fault diagnosis methods are presented.