bluuebunny/crossref_metadata_2025 huggingface dataset:
Nano‐dielectrics in biosystems
Authors: Xu Jingjing , Wang Fan , Song Yihan , Ge Song , Xu Shengyong
Published: March 2021

Here, the nano‐sized dielectrics in biosystems and their functions are reviewed. For a variety of electromagnetic phenomena observed in biosystems, from a generation of weak electrical pulses in all kinds of neural systems to generation of high‐power electrical pulses for sensing and attacking preys in electric eels, nano‐dielectrics, such as lipid membrane, always play an important role. The electromagnetic pulses in neural systems are created by transmembrane ionic fluxes through a cluster of ion channels embedded in a lipid membrane, but the high‐power pulses released by electric eels are simultaneously generated by billions of ion channels. An overlooked function of the nano‐dielectrics is that they build up a network serving as the major transmitting paths for electromagnetic pulses in dendrites and axons, and even in ordinary cell membranes. Many fundamental questions in the working mechanisms of nano‐dielectrics in nature biosystems remain open and answers to these questions may lead to novel, high‐efficiency manmade power supplies and a better understanding of brain functions.
Delivering more to cell edge via joint multi‐cell non‐orthogonal multiple access and traffic offloading
Authors: Zhao Yi , Yuan Di , You Lei
Published: March 2021

We consider leveraging the joint potential of non‐orthogonal multiple access (NOMA) and traffic offloading to benefit cell‐edge users in multi‐cell scenarios. We formulate the edge‐driven throughput maximisation problem where both the offloading decision and resource allocation are to be optimised, accounting for the impact of the inter‐cell interference on the decoding order in NOMA. The inter‐cell interference is not given constants as it is influenced by resource allocation. Therefore the non‐orthogonal multiple access (NOMA) decoding order is not known a priori. We explore the problem by decomposing it into two subproblems. By analysis of structural properties, we derive algorithm modules which interact iteratively for reciprocity, forming the overall algorithm. Numerical results show that the proposed scheme considerably improves the cell‐edge throughput, compared with the conventional scheme of orthogonal multiple access without traffic offloading.
Distributed localization algorithm for wireless sensor networks using range lookup and subregion stitching
Authors: Khan Farhan , Nguang Sing Kiong
Published: March 2021

One of the ways in which localization algorithms in wireless sensor networks (WSNs) have been categorized is whether they are range‐based or range‐free. Range‐based algorithms use expensive hardware to measure one or more physical quantities and, in turn, use them to localize nodes with greater precision. In contrast, range‐free algorithms use coarse‐grained quantities like connectivity to localize nodes with limited precision. A middle way between these two approaches can be called a partial range‐based approach that can utilize the existing received signal strength indicator (RSSI) readings from sensor nodes to improve the already existing coarse‐grained localization methods. Another important consideration in WSNs is that a distributed localization algorithm is more computationally feasible as compared to its centralized counterpart. Keeping these two considerations in mind, a distributed localization algorithm is proposed here which falls in the aforementioned partial range‐based category. The proposed algorithm called RangeLookup‐MDS first creates subregions using connectivity information only. This is followed by the collection of RSSI readings from individual sensor nodes that are used to perform range lookup for inter‐node distance estimates in a lookup table. After that, relative localization in every subregion is performed using multidimensional scaling, and then the relative maps are stitched together to create a consistent (but relative) coordinate system. The algorithm also has the capability to compute absolute coordinates in two‐dimensional if the stitching step is executed with at least three non‐collinear anchor nodes with known locations. Simulation results on uniform as well as irregular networks of various sizes show that the proposed algorithm provides improved localization accuracy and reduces localization error up to 25% in comparison to a previous partial range‐based localization algorithm.
Modeling the mixed-morphology supernova remnant IC 443
Authors: Ustamujic S. , Orlando S. , Greco E. , Miceli M. , Bocchino F. , Tutone A. , Peres G.
Published: March 2021

Context. The morphology and the distribution of material observed in supernova remnants (SNRs) reflect the interaction of the supernova (SN) blast wave with the ambient environment, the physical processes associated with the SN explosion, and the internal structure of the progenitor star. IC 443 is a mixed-morphology (MM) SNR located in a quite complex environment: it interacts with a molecular cloud in the northwestern and southeastern areas and with an atomic cloud in the northeast.

Aims. In this work, we aim to investigate the origin of the complex morphology and multi-thermal X-ray emission observed in SNR IC 443 through the study of the effect of the inhomogeneous ambient medium in shaping its observed structure and an exploration of the main parameters characterizing the remnant.

Methods. We developed a 3D hydrodynamic (HD) model for IC 443, which describes the interaction of the SNR with the environment, parametrized in agreement with the results of the multi-wavelength data analysis. We performed an ample exploration of the parameter space describing the initial blast wave and the environment, including the mass of the ejecta, the energy and position of the explosion, as well as the density, structure, and geometry of the surrounding clouds. From the simulations, we synthesized the X-ray emission maps and spectra and compared them with actual X-ray data collected by XMM-Newton.

Results. Our model explains the origin of the complex X-ray morphology of SNR IC 443 in a natural way, with the ability to reproduce, for the first time, most of the observed features, including the centrally-peaked X-ray morphology (characteristic of MM SNRs) when considering the origin of the explosion at the position where the pulsar wind nebula CXOU J061705.3+222127 was at the time of the explosion. In the model that best reproduces the observations, the mass of the ejecta and the energy of the explosion are ~7 M⊙ and ~1 × 1051 erg, respectively. From the exploration of the parameter space, we find that the density of the clouds is n > 300 cm−3 and that the age of SNR IC 443 is ~8000 yr.

Conclusions. The observed inhomogeneous ambient medium is the main property responsible for the complex structure and the X-ray morphology of SNR IC 443, resulting in a very asymmetric distribution of the ejecta due to the off-centered location of the explosion inside the cavity formed by the clouds. It can be argued that the centrally peaked morphology (typical of MM SNRs) is a natural consequence of the interaction with the complex environment. A combination of high resolution X-ray observations and accurate 3D HD modeling is needed to confirm whether this scenario is applicable to other MM SNRs.
Was Bilder über unseren Beruf aussagen – Mediale Repräsentanz der Therapieberufe
Authors: Höppner Heidi , Kalinitschenko Natalie
Published: March 2021

Ergotherapie-Studierende der Alice Salomon Hochschule Berlin haben sich mit der Frage beschäftigt, wie ihre Profession in den Medien dargestellt wird. In Form von Collagen hielten sie ihre Ergebnisse fest und befassten sich kritisch mit dem Bild, das die Gesellschaft von Therapieberufen hat.
Kritisches Weißsein – Weiße Privilegien und rassismuskritisches Handeln in der Ergotherapie
Authors: Roth Christina
Published: March 2021

Rassismus ist in unserer Gesellschaft als Machtsystem fest verankert. Im Alltag und in der Therapie tragen wir oft unbewusst zur Aufrechterhaltung von Rassismus bei, weil wir alle rassistisch sozialisiert sind. Um als weiße Ergotherapeut*innen antirassistisch zu handeln, braucht es eine Auseinandersetzung mit der eigenen Involviertheit in rassistische Strukturen und mit weißen Privilegien.
Angebotsstrukturen der ambulanten vertragsärztlichen Versorgung: Deutschland und andere dezentral organisierte Gesundheitssysteme
Authors: Hahn Ursula , Baulig Christine , Brzoska Patrick
Published: March 2021

Hintergrund Das Bild vertragsärztlicher Versorgung ist arztbezogen; wenig beachtet wird der (potentielle) Einfluss von Versorgungsorganisationen (VO) und deren Merkmalen auf das Versorgungsgeschehen.

Ziel Beschreibung der organisationsbezogenen Angebotsstrukturen nach Rechtsformen, Abgleich mit denen anderer dezentral organisierter Gesundheitssysteme und Diskussion, ob sich entlang der Rechtsform Effekte für verschiedene Dimensionen des Versorgungsgeschehens zeigen lassen.

Material und Methoden Die Häufigkeiten von Einzelpraxis, Gemeinschaftspraxis und Medizinischen Versorgungszentren (MVZ) für haus- und fachärztliche Versorgungsbereiche, die durchschnittliche ärztliche Teamstärke und der Anteil der VO mit interdisziplinärer Aufstellung werden auf Basis von Sekundärdatenquellen (überwiegend Kassenärztliche Bundesvereinigung) im Zeitablauf beschrieben.

Ergebnisse Die Angebotsstrukturen sind durch hohe Fragmentierung (2018:>80 000 VO) mit hohem Anteil von Kleinstorganisationen (über alle VO 73% Einzelpraxen), niedriger durchschnittlicher Teamstärke (über alle VO 1,7 Ärzte) und geringem Anteil mit interdisziplinärer Aufstellung (17% aller Gemeinschaftspraxen und MVZ) bei geringer Konzentrationsdynamik in der haus- und fachärztlichen Versorgung geprägt.

Schlussfolgerungen Die Kleinteiligkeit der deutschen Angebotsstrukturen ist ausgeprägter bzw. persistierender als die in anderen dezentralen Gesundheitssystemen. Rechtsformen und Durchschnittswerte erfassen die Heterogenität der VO-Morphologien nur unzureichend. Wünschenswert, z. B. für eine gezielte Versorgungssteuerung, wäre eine breitere Datenbasis zu mehr organisationsbezogenen Merkmalen.
Studies towards the Synthesis of (–)-Pulvomycin: Construction of the C12–C40 Segment by a Stereoselective Aldol Reaction
Authors: Bach Thorsten , Wienhold Sebastian , Fritz Lukas , Judt Tatjana , Hackl Sabrina , Neubauer Thomas , Sauerer Bastian
Published: March 2021

A convergent strategy was developed for the synthesis of the C12–C40 segment of (–)-pulvomycin. Key step was a diastereoselective aldol reaction between a chiral ethyl ketone representing the C24–C40 fragment and a chiral aldehyde representing the C12–C23 fragment. Both compounds were prepared from enantiomerically pure building blocks in a convergent fashion. The longest linear sequence commenced with a known d-fucose-derived glycosyl donor and entailed a total number of 16 steps. The desired anti-aldol product was obtained in a total yield of 5% over these steps and contains 12 out of 13 stereogenic centers present in the natural product.
Searching the PDF Haystack: Automated Knowledge Discovery in Scanned EHR Documents
Authors: Kostrinsky-Thomas Alexander L. , Hisama Fuki M. , Payne Thomas H.
Published: March 2021

Background Clinicians express concern that they may be unaware of important information contained in voluminous scanned and other outside documents contained in electronic health records (EHRs). An example is “unrecognized EHR risk factor information,” defined as risk factors for heritable cancer that exist within a patient's EHR but are not known by current treating providers. In a related study using manual EHR chart review, we found that half of the women whose EHR contained risk factor information meet criteria for further genetic risk evaluation for heritable forms of breast and ovarian cancer. They were not referred for genetic counseling.

Objectives The purpose of this study was to compare the use of automated methods (optical character recognition with natural language processing) versus human review in their ability to identify risk factors for heritable breast and ovarian cancer within EHR scanned documents.

Methods We evaluated the accuracy of the chart review by comparing our criterion standard (physician chart review) versus an automated method involving Amazon's Textract service (Amazon.com, Seattle, Washington, United States), a clinical language annotation modeling and processing toolkit (CLAMP) (Center for Computational Biomedicine at The University of Texas Health Science, Houston, Texas, United States), and a custom-written Java application.

Results We found that automated methods identified most cancer risk factor information that would otherwise require clinician manual review and therefore is at risk of being missed.

Conclusion The use of automated methods for identification of heritable risk factors within EHRs may provide an accurate yet rapid review of patients' past medical histories. These methods could be further strengthened via improved analysis of handwritten notes, tables, and colloquial phrases.
Invasive dynamics for a predator–prey system with Allee effect in both populations and a special emphasis on predator mortality
Authors: Rana Sourav , Bhowmick Amiya Ranjan , Sardar Tridip
Published: March 2021

We considered a non-linear predator–prey model with an Allee effect on both populations on a two spatial dimension reaction-diffusion setup. Special importance to predator mortality was given as it may be often controlled through human-made harvesting processes. The local dynamics of the model was studied through boundedness, equilibrium, and stability analysis. An extensive numerical stability analysis was performed and found that bi-stability is not possible for the non-spatial model. By analyzing the spatial model, we found the condition for successful invasion and the persistence region of the species based on the predator Allee effect and its mortality parameter. Four different dynamics in this region of the parameter space are mainly explored. First, the Allee effect on both populations leads to various new types of species spread. Second, for a high value of per-capita growth rate, two completely new spreads (e.g., sun surface, colonial) have been found depending on the Allee effect parameter. Third, the Allee coefficient on the predator population leads to spatiotemporal chaos via a patchy spread for both linear and quadratic mortality rates. Finally, a more rigorous analysis is performed to study the chaotic nature of the system within the whole persistence domain. We have studied the possibility of chaos through temporal variation in different invasion regions. Furthermore, the chaotic fluctuation is studied through the sensitivity of initial conditions and by investigating the dominant Lyapunov exponent value.
Analytical gradients for molecular-orbital-based machine learning
Authors: Lee Sebastian J. R. , Husch Tamara , Ding Feizhi , Miller Thomas F.
Published: March 2021

Molecular-orbital-based machine learning (MOB-ML) enables the prediction of accurate correlation energies at the cost of obtaining molecular orbitals. Here, we present the derivation, implementation, and numerical demonstration of MOB-ML analytical nuclear gradients, which are formulated in a general Lagrangian framework to enforce orthogonality, localization, and Brillouin constraints on the molecular orbitals. The MOB-ML gradient framework is general with respect to the regression technique (e.g., Gaussian process regression or neural networks) and the MOB feature design. We show that MOB-ML gradients are highly accurate compared to other ML methods on the ISO17 dataset while only being trained on energies for hundreds of molecules compared to energies and gradients for hundreds of thousands of molecules for the other ML methods. The MOB-ML gradients are also shown to yield accurate optimized structures at a computational cost for the gradient evaluation that is comparable to a density-corrected density functional theory calculation.
Development of the ion cyclotron emission diagnostic for the W7-X stellarator
Authors: Moseev D. , Ochoukov R. , Bobkov V. , Dendy R. O. , Faugel H. , Hartmann D. , Kallmeyer J.-P. , Lansky J. , Laqua H. P. , Marsen S. , McClements K. G. , Nielsen S. K. , Reintrog A. , Salewski M. , Schmidt B. S. , Schulz T. , Stange T. ,   W7-X Team
Published: March 2021

An ion cyclotron emission (ICE) diagnostic is prepared for installation into the W7-X stellarator, with the aim to be operated in the 2022 experimental campaign. The design is based on the successful ICE diagnostic on the ASDEX Upgrade tokamak. The new diagnostic consists of four B-dot probes, mounted about 72° toroidally away (one module) from the neutral beam injector, with an unobstructed plasma view. Two of the B-dot probes are oriented parallel to the local magnetic field, aimed to detect fast magnetosonic waves. The remaining two probes are oriented poloidally, with the aim to detect slow waves. The radio frequency (RF) signals picked up by the probes are transferred via 50 Ω vacuum-compatible coaxial cables to RF detectors. Narrow band notch filters are used to protect the detectors from possible RF waves launched by the W7-X antenna. The signal will be sampled with a four-channel fast analog-to-digital converter with 14 bit depth and 1 GSample/s sampling rate. The diagnostic’s phase–frequency characteristic is properly measured in order to allow measuring the wave vectors of the picked up waves.
Energy efficiency analysis of mass transport enhancement in time-periodic oscillatory electroosmosis
Authors: Huang Hsin-Fu , Huang Kun-Hao
Published: March 2021

The streamwise mass transport of passive, neutral non-reacting solutes in oscillatory electroosmotic microchannel flows is theoretically investigated from an energy consumption and efficiency perspective for general asymmetric wall zeta potentials and slip velocities. Analytical solutions to the averaged mass transport and total power input (consisting of Joule heating, viscous dissipation, and sliding friction) are obtained and expressed in terms of the relevant parameters governing the system. Particularly, we define a “χg-parameter” to quantify the mass transport gained (excluding pure diffusion) per total power input in our analysis and discussions. While the no-slip, symmetric potential χg-performances agree with the mass transport results reported in previous literature, a “resonance like” behavior in the χg-performances is identified for large enough Womersley numbers and symmetric slip lengths despite the extra sliding friction, viscous dissipation, and Joule heating consumptions in the symmetric zeta potential configuration. When favorable asymmetries in the wall potentials and slip lengths are introduced, the χg-performances are not only considerably improved, but also highly correlated with the magnitudes of the velocity gradients in the oscillatory velocity profiles, hence reinforcing the physical picture of Taylor–Aris dispersion. Geometric symmetry can be identified among distinct velocity profiles which yield the same χg-performance. These profiles are generally associated with particular families of wall potential and/or slip length combinations also exhibiting symmetry among one another. Finally, the aspect ratio of the slit microchannel (width divided by length) is found to play a crucial role in significantly improving the χg-energy efficiency of mass transport in time-periodic electroosmosis.
Effect of Cu-doping on the magnetic and electrical transport properties of three-quarter Heusler alloy ZrCo1.5Sn
Authors: Huang Hui , Qiu Pengfei , Gao Zhiqiang , Xiao Jie , Shi Xun , Chen Lidong
Published: March 2021

Recently, defective three-quarter Heusler compounds MCo1.5Sn (M = Ti, Zr, and Hf) have been reported with interesting crystal structure differing from the traditional half-Heusler and full-Heusler compounds. These defective compounds are metallic ferromagnets, but the detailed correlation between magnetic and electrical transport properties is still unclear. In this study, we dope Cu in ZrCo1.5Sn to dilute the magnetic Co atoms with the purpose of clarifying how the magnetism influences the electrical transport properties in the defective three-quarter Heusler compounds. Significantly lowered ferromagnetic transition temperature and decreased saturated magnetic moment are observed in Cu-doped ZrCo1.5Sn due to the diluted Co atoms. Likewise, in the ferromagnetic phase, the dominant carrier scattering mechanism is changed from spin fluctuation scattering to magnetic impurity scattering. The doped Cu atoms introduce non-bonding states below the valence band maximum, resulting in the appearance of a narrow bandgap around 0.1 eV. Correspondingly, the electric transport behavior in the paramagnetic phase shows a semiconducting character with a negative temperature dependence of resistivity. This study provides further understanding to the correlation between magnetic properties and electrical transport properties in defective Heusler-based compounds.
Evaporation from arbitrary nanoporous membrane configurations: An effective evaporation coefficient approach
Authors: John Benzi , Gibelli Livio , Enright Ryan , Sprittles James E. , Lockerby Duncan A. , Emerson David R.
Published: March 2021

Thin-film evaporation from nanoporous membranes is a promising cooling technology employed for the thermal management of modern electronic devices. We propose an effective one-dimensional analytical approach that can accurately predict the temperature and density jump relations, and evaporation rates, for arbitrary nanoporous membrane configurations. This is accomplished through the specification of an effective evaporation coefficient that encompasses the influence of different system parameters, such as porosity, meniscus shape, evaporation coefficient, and receding height. Our proposed approach can accurately predict all the typical output evaporation parameters of interest like mass flux, and temperature and density jumps, without the need to carry out computationally demanding numerical simulations. Several exemplar cases comprising of nanoporous configurations with a wide range of parameters have been considered to demonstrate the feasibility and accuracy of this analytic approach. This work thus enables a quick, efficient, and accurate means of aiding the design and engineering analysis of nanoporous membrane-based cooling devices.
Evaluating the effects of shelter-in-place policies during the COVID-19 pandemic
Authors: Berry Christopher R. , Fowler Anthony , Glazer Tamara , Handel-Meyer Samantha , MacMillen Alec
Published: March 2021

Significance

We study the health, behavioral, and economic effects of one of the most politically controversial policies in recent memory, shelter-in-place orders during the COVID-19 pandemic. Previous studies have claimed that shelter-in-place orders saved thousands of lives, but we reassess these analyses and show that they are not reliable. We find that shelter-in-place orders had no detectable health benefits, only modest effects on behavior, and small but adverse effects on the economy. To be clear, our study should not be interpreted as evidence that social distancing behaviors are not effective. Many people had already changed their behaviors before the introduction of shelter-in-place orders, and shelter-in-place orders appear to have been ineffective precisely because they did not meaningfully alter social distancing behavior.
The defaultness hypothesis
Authors: Giora Rachel
Published: March 2021

This paper demonstrates that, when interpretation is at stake, it is only degree of defaultness that matters. Neither degree of Negation, nor degree of Affirmation, nor equal degree of Novelty, nor equal degree of Literalness/Nonliteralness, nor equal strength of Contextual support, whether linguistic or pictorial (see Heruti et al. 2019), makes a difference. Instead, it is only degree of defaultness that counts. Indeed, having established degree of defaultness of negatives and affirmatives (Experiment 1.1) and their processing cost when in isolation (Experiment 1.2), we further attested to the speed superiority of default negative interpretations, which seemed more pronounced in the Left Hemisphere rather than in the Right Hemisphere (Experiment 1.2; see Giora, Cholev et al. 2018).We then further attested to the speed superiority of these negatives, when embedded in equally strong supportive contexts. Here, we also show that default Negative Sarcasm is processed significantly faster than nondefault Affirmative Sarcasm (Experiment 2). And when embedded in equally strong sarcastically biasing contexts, both hemispheres reflect the superiority of default Negative Sarcasm over nondefault Affirmative Sarcasm (Experiments 2.1–2.2). However, given Affirmative Sarcasm’s nondefaultness, it is only nondefault Affirmative Sarcasmthat is expected and shown to rely on cueing for its derivation (Corpus-based Studies 1–2, Section 3). Still, when hedonic effects are considered (see Section 4), it is only utterances’ nondefault interpretations, whether in linguistic (Experiment 3) or pictorial contexts (Experiment 4), that are entertaining, given that they make up Optimal Innovations, while involving default interpretations in the process (see Giora et al. 2004, 2017). It is degree of defaultness, then, that affects both (i) processing speed (whether in or out of context), (ii) reliance on cueing, and (iii) hedonic effects. Finally, in Section 5, our results and conclusions are summarized.
Unweaving the embodied nature of English temporal prepositions
Authors: Morras Cortés Javier A. , Wen Xu
Published: March 2021

The metaphortime is space(Lakoff & Johnson 1999) and the pervasiveness of metaphor and image-schematic structure in human conceptualization (Johnson 1987;Hampe 2005) have been widely accepted among cognitive scientists as constructs that help explain non-spatial and temporal linguistic constructions. However, Conceptual Metaphor Theory (CMT) might not be the whole story. While it is acceptable that moments in time can be construed as being analogous to points in space as in utterances such asatthe cornervs.at2:30, there seems to be much moretemporal cognitionthan previously thought. It turns out that time exhibits its own structure (followingEvans 2004,2013;Galton 2011) that is based on transience. This idea has made some scholars support the weak version of CMT which posits that the temporal meaning of prepositions is represented and processed independently of the corresponding spatial meanings (seeKemmerer 2005for such a view). The present article supports the idea that spatial and temporal structures complement each other in order to achieve temporal conceptions. This is indeed a conceptual pattern showed by the English prepositionatthat makes use of an extrinsic temporal reference to activate its temporal semantics. To analyze the different temporal realizations thatatmay have, the paper aims to identify the topological structure that underlies theconceptual basisof this preposition. This allows us to appreciate how the spatio-conceptual structure ofatpartially structures temporal conceptions. The paper also identifies the nature of the temporal structure that is involved in temporal realizations. The article concludes with some remarks, among them the pivotal role of the schematic temporal structure that is captured by the extrinsic temporal reference, and the role of conceptual metaphor in underdetermining temporal thinking.
Our metaphorical minds
Authors: Su Lily I-wen
Published: March 2021

Aside from metaphor being an important language device reflecting human cognition, it also provides a window into the
understanding of culture (Kövecsec 2019). Language is a function of culture because it is a form
of the verbal and nonverbal systems by which a group member can communicate with another member. Language connects people of the same
cultural identity because it functions as a common bond between people who have the same linguistic heritage. As argued in Verhagen (2008), values of one’s understanding of the world he lives in may in turn be influenced by
the conceptual metaphors he unconsciously holds to visualize his world. Verhagen has provided a valuable standpoint, yet it is
western-centered and European-oriented. Through metaphors identified in Chinese in proverbs, food, marriage, and time expressions, this
paper intends to address the following questions: Does conceptual metaphors reflect any specific Chinese mode of thinking? Does
such conceptualization give a taste of Chinese culture? What kind(s) of theoretical and pragmatic implications can be derived from our line
of investigation? It is thus hoped that this paper may provide empirical evidence with reference to mappings between thought and language,
which in turn, may serve as a way to explore culture.
Hedychium gardnerianum (kahili ginger).
Authors: Djeddour Djamila
Published: March 2021

Native to the Eastern Himalayas, H. gardnerianum has been widely introduced as an ornamental in different regions of the world. It continues to be available as an ornamental and is therefore likely to spread further.H. gardnerianum is an ecologically versatile plant with rapid vegetative growth, the dense rhizome system of the plant prevents regeneration of other species. This very aggressive, shade-tolerant plant is able to form dense thickets on undisturbed sites in the understorey of open and closed-canopy native rain forests and managed forests, as well as in open areas (forest margins, ravines or path sides). Its high seed production and efficient dispersal by rats and birds, allows it to persist in invaded areas for a long time and establish new points of invasion. As H. gardnerianum is able to invade native forests, ecological, conservation and cultural values are threatened and it is a major threat to native biodiversity.
Effects of Quantum Noise on Quantum Approximate Optimization Algorithm
Authors: Xue Cheng , Chen Zhao-Yun , Wu Yu-Chun , Guo Guo-Ping
Published: March 2021

The quantum-classical hybrid algorithm is a promising algorithm with respect to demonstrating the quantum advantage in noisy-intermediate-scale quantum (NISQ) devices. When running such algorithms, effects due to quantum noise are inevitable. In our work, we consider a well-known hybrid algorithm, the quantum approximate optimization algorithm (QAOA). We study the effects on QAOA from typical quantum noise channels, and produce several numerical results. Our research indicates that the output state fidelity, i.e., the cost function obtained from QAOA, decreases exponentially with respect to the number of gates and noise strength. Moreover, we find that when noise is not serious, the optimized parameters will not deviate from their ideal values. Our result provides evidence for the effectiveness of hybrid algorithms running on NISQ devices.
Advection and Thermal Diode
Authors: Li Ying , Li Jiaxin
Published: March 2021

We prove that under the condition of closed boundary to mass flux, pure advection is not a valid mechanism to make a practical thermal diode. Among the various designs of thermal diodes, many of them involve circulating fluid flow, such as in thermosyphons. However, those designs often employ natural convection, which is basically a nonlinear process. It thus remains unclear how the pure advection of temperature field induced by a decoupled velocity field influences the symmetry of heat transfer. Here we study three typical models with pure advection: one with open boundary, one with closed boundary at unsteady state, and one with closed boundary at steady state. It is shown that only the last model is practical, while it cannot become a thermal diode. Finally, a general proof is given for our claim by analyzing the diffusive reciprocity.
Quantum Transport across Amorphous-Crystalline Interfaces in Tunnel Oxide Passivated Contact Solar Cells: Direct versus Defect-Assisted Tunneling
Authors: Li Feng , Duan Weiyuan , Pomaska Manuel , Köhler Malte , Ding Kaining , Pu Yong , Aeberhard Urs , Rau Uwe
Published: March 2021

Tunnel oxide passivated contact solar cells have evolved into one of the most promising silicon solar cell concepts of the past decade, achieving a record efficiency of 25%. We study the transport mechanisms of realistic tunnel oxide structures, as encountered in tunnel oxide passivating contact (TOPCon) solar cells. Tunneling transport is affected by various factors, including oxide layer thickness, hydrogen passivation, and oxygen vacancies. When the thickness of the tunnel oxide layer increases, a faster decline of conductivity is obtained computationally than that observed experimentally. Direct tunneling seems not to explain the transport characteristics of tunnel oxide contacts. Indeed, it can be shown that recombination of multiple oxygen defects in a-SiO
x
can generate atomic silicon nanowires in the tunnel layer. Accordingly, new and energetically favorable transmission channels are generated, which dramatically increase the total current, and could provide an explanation for our experimental results. Our work proves that hydrogenated silicon oxide (SiO
x
:H) facilitates high-quality passivation, and features good electrical conductivity, making it a promising hydrogenation material for TOPCon solar cells. By carefully selecting the experimental conditions for tuning the SiO
x
:H layer, we anticipate the simultaneous achievement of high open-circuit voltage and low contact resistance.
Rotational superradiance with Bogoliubov dispersion
Authors: Patrick Sam
Published: March 2021

Rotational superradiance affects the dynamics of many rotating systems in nature, through either stimulated or spontaneous extraction of energy and angular momentum. By now, this process is well-studied in the relativistic setting, where systems are intrinsically dispersion-free. In many condensed matter systems, however, dispersion is an unavoidable aspect of the description for the short wavelength modes. For these systems, how might one expect superradiance to be modified? In this work, an answer to this question is provided using an illustrative example. The scattering of linear excitations of a Bose–Einstein condensate (BEC) are studied in the presence of a rotating, draining vortex flow using the full Bogoliubov dispersion relation. It is shown that dispersion suppresses the extraction of energy and angular momentum, firstly, by decreasing the superradiant bandwidth, and secondly, by preventing high-angular momentum modes from superradiating.
3D Compton scattering imaging with multiple scattering: analysis by FIO and contour reconstruction
Authors: Rigaud Gaël
Published: March 2021

3D Compton scattering imaging (CSI) is an upcoming concept exploiting the scattering of photons induced by the electronic structure of the object under study. The so-called Compton scattering rules the collision of particles with electrons and describes their energy loss after scattering. Although physically relevant, multiple-order scattering was so far not considered and therefore, only first-order scattering is generally assumed in the literature. The purpose of this work is to argument why and how a contour reconstruction of the electron density map from scattered measurement composed of first- and second-order scattering is possible (scattering of higher orders are here neglected). After the development of integral representations for the first- and second-order scattering, we approximate these models by Fourier integral operators (FIO) and study their smoothness properties. The second-order scattered radiation reveals itself to be structurally smoother than the radiation of first-order indicating that the contours of the electron density are essentially encoded within the first-order part. This opens the way to contour-based reconstruction techniques when considering multiple scattered data. Our main results, modeling and reconstruction scheme, are successfully implemented on synthetic and Monte-Carlo data.
Twisted-shape selection of self-assembled Si

⟨100⟩

nanobelts and nanowires
Authors: Danesh V , Pishkenari H Nejat , Zohoor H
Published: March 2021

This letter discusses the surface-reconstruction-induced self-twisting behavior of Si〈100〉 nanobelts and nanowires (NWs) with rectangular cross section. Giving a thorough physical interpretation, we explain the reason behind this phenomenon and present a continuum-based model. It is revealed that these structures can self-assemble into both right- and left-handed helicoids depending on their crystal arrangements. More specifically, for NWs with the same number of layers in each of their cross sections directions, two distinct values of torsion angle are possible for each of right- and left-handed twisted morphologies. In conclusion, four modes of torsion can be observed in Si〈100〉 NWs. Furthermore, some atomistic simulations are conducted to substantiate analytical results by utilizing Tersoff’s potential. These results confirm the precision of the analytical discussions and are in good agreement with the continuum model predictions. Finally, the results of Tersoff’s potential are validated by a density functional based tight-binding model.
Machine learning for proton path tracking in proton computed tomography
Authors: Lazos Dimitrios , Collins-Fekete Charles-Antoine , Bober Miroslaw , Evans Philip , Dikaios Nikolaos
Published: March 2021

A Machine Learning approach to the problem of calculating the proton paths inside a scanned object in proton Computed Tomography is presented. The method is developed in order to mitigate the loss in both spatial resolution and quantitative integrity of the reconstructed images caused by multiple Coulomb scattering of protons traversing the matter. Two Machine Learning models were used: a forward neural network (NN) and the XGBoost method. A heuristic approach, based on track averaging was also implemented in order to evaluate the accuracy limits on track calculation, imposed by the statistical nature of the scattering. Synthetic data from anthropomorphic voxelized phantoms, generated by the Monte Carlo (MC) Geant4 code, were utilized to train the models and evaluate their accuracy, in comparison to a widely used analytical method that is based on likelihood maximization and Fermi−Eyges scattering model. Both NN and XGBoost model were found to perform very close or at the accuracy limit, further improving the accuracy of the analytical method (by 12% in the typical case of 200 MeV protons on 20 cm of water object), especially for protons scattered at large angles. Inclusion of the material information along the path in terms of radiation length did not show improvement in accuracy for the phantoms simulated in the study. A NN was also constructed to predict the error in path calculation, thus enabling a criterion to filter out proton events that may have a negative effect on the quality of the reconstructed image. By parametrizing a large set of synthetic data, the Machine Learning models were proved capable to bring—in an indirect and time efficient way—the accuracy of the MC method into the problem of proton tracking.
Light-weight cross-view hierarchical fusion network for joint localization and identification in Alzheimer’s disease with adaptive instance-declined pruning
Authors: Han Kangfu , Luo Jiaxiu , Xiao Qing , Ning Zhenyuan , Zhang Yu
Published: March 2021

Magnetic resonance imaging (MRI) has been widely used in assessing development of Alzheimer’s disease (AD) by providing structural information of disease-associated regions (e.g. atrophic regions). In this paper, we propose a light-weight cross-view hierarchical fusion network (CvHF-net), consisting of local patch and global subject subnets, for joint localization and identification of the discriminative local patches and regions in the whole brain MRI, upon which feature representations are then jointly learned and fused to construct hierarchical classification models for AD diagnosis. Firstly, based on the extracted class-discriminative 3D patches, we employ the local patch subnets to utilize multiple 2D views to represent 3D patches by using an attention-aware hierarchical fusion structure in a divide-and-conquer manner. Since different local patches are with various abilities in AD identification, the global subject subnet is developed to bias the allocation of available resources towards the most informative parts among these local patches to obtain global information for AD identification. Besides, an instance declined pruning algorithm is embedded in the CvHF-net for adaptively selecting most discriminant patches in a task-driven manner. The proposed method was evaluated on the AD Neuroimaging Initiative dataset and the experimental results show that our proposed method can achieve good performance on AD diagnosis.
Particle-in-cell simulations of parallel dynamics of a blob in the scrape-off-layer plasma of a generic medium-size tokamak
Authors: Costea S , Kovačič J , Tskhakaya D , Schrittwieser R , Gyergyek T , Popov Tsv K
Published: March 2021

In this work we investigate, in a fully-kinetic particle approach, the evolution of a blob inside a flux tube in the scrape-off-layer (SOL) plasma of a generic diverted medium-size tokamak and its contribution to the recorded particle and energy flux densities at the divertor. Initially, a steady-state background plasma is reached, with realistic plasma profiles in the parallel direction. On top of it, a blob source with given intensity and temperature is superimposed at the outer midplane. The blob source is active for 10

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in order to emulate a generic blob with 1 cm diameter crossing the magnetic flux tube with a typical 1 km s−1 radial drift velocity. We have observed that most of the blob’s hot electrons are screened off by the cold electrons of the SOL plasma and can travel towards the two divertors free of the initial ambipolar forces. Performing a density scan and having a blob-to-background density ratio

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in the source region, we observe that due to Coulomb collisions these hot electrons can reach the outer divertor or also the inner one, depending on the density of the background SOL plasma. Consequently, the midplane–divertor potential difference increases and the sheath expands leading to a significant increase in the background ion energy flux density onto the divertor. We also observe that when the blob ions reach the divertor the electron flux density on the divertor increases due to ambipolar forces. Through Coulomb collisions, a part of the thermal energy of the hot blob ions is transferred to the main (background) plasma, depending on the plasma density. Most of the energy deposited into the divertor is brought by the ions and the blob-induced background ion energy flux density becomes comparable (low-density case) or much higher (high-density case) than the blob ion energy flux density.
Kinetic equilibrium reconstructions of plasmas in the MAST database and preparation for reconstruction of the first plasmas in MAST upgrade
Authors: Berkery J W , Sabbagh S A , Kogan L , Ryan D , Bialek J M , Jiang Y , Battaglia D J , Gibson S , Ham C
Published: March 2021

Reconstructions of plasma equilibria using magnetic sensors were routine during operation of the Mega Ampere Spherical Tokamak (MAST) device, but reconstructions using kinetic profiles were not. These are necessary for stability and disruption analysis of the MAST database, as well as for operation in the upgrade to the device, MAST-U. The three-dimensional (3D) code VALEN is used to determine eddy currents in the 3D vessel structures for vacuum coil test shots, which are then mapped to effective resistances in the two-dimensional vessel groupings in the EFIT equilibrium reconstruction code to be used in conjunction with nearby loop voltage measurements for estimated currents in the structures during reconstruction. Kinetic equilibrium reconstructions with EFIT, using all available magnetic sensors as well as Thomson scattering measurements of electron temperature and density, charge exchange recombination spectroscopy measurements of ion temperature, and internal magnetic field pitch angle measurements from a motional Stark effect (MSE) diagnostic are performed for a large database of MAST discharges. Excellent convergence errors are obtained for the portions of the discharges where the stored energy was not too low, and it is found that reconstructions performed with temperature and density measurements but without MSE data usually already match the pitch angle measurements well. A database of 275 kinetic equilibria is used to test the ideal MHD stability calculation capability for MAST. Finally, the necessary changes to conducting structure in VALEN, and diagnostic setup in EFIT have been completed for the upgrade from MAST to MAST-U, enabling kinetic reconstructions to commence from the first plasma discharges of the upgraded device.
Demonstration of an efficient single flux quantum logic circuit by introducing a local magnetic flux biasing
Authors: Asada Shunta , Yamanashi Yuki , Yoshikawa Nobuyuki
Published: March 2021

We investigated local magnetic flux biasing (LFB) that induces a phase shift in superconductor circuits by locally applying a magnetic field through the superconductor loop with Josephson junctions. The arbitrary phase shift can be achieved using LFB without modifying the circuit fabrication process. To quantitatively evaluate the effects of introducing LFB for practical superconductor circuit applications, we designed a single flux quantum (SFQ) based non-destructive read-out flip-flop with complementary outputs (NDROC) and a delay flip-flop with complementary outputs (DFFC). The circuit area and static power consumption of the NDROC based on LFB architecture (LFB-NDROC) are approximately 67% and 36% of a conventional NDROC, respectively. The measured bias margin of the LFB-NDROC was in the range of 69%–129%. Using LFB, we were able to reduce the circuit area and power consumption for the DFFC by 67% and 83%, respectively. The measured bias margin of the DFFC with LFB was between 115% and 128%. LFB enabled us to implement a 5-to-32 SFQ decoder which comprises NDROC trees with a reduced circuit area of approximately 60% of a conventional decoder. The results obtained in this study can be applied to not just SFQ circuits but other superconductor circuits also, as they improve the area and power efficiency of such circuits.
Research on a Three-phase Flow Electromagnetic Measurement Method
Authors: Li Xuejing , Li Haiyang
Published: March 2021

For a long time, industrial and agricultural production has a wide range of requirements for energy saving and emission reduction. The flow parameter detection of water/gas/oil three-phase flow is of great significance in the control and optimization of the petroleum industry process. Using the principle of correlation method, a multi-electrode electromagnetic measurement method is designed to measure the three-phase flow. The system has the function of self-detection of the meter zero point. The finite element method is used to calculate and analyze the distribution of sensitive fields inside the flow measurement sensor and the influence of different physical parameters of non-conductive objects on the disturbance characteristics of the flow measurement sensor. And through experiments to prove the feasibility, stability and accuracy of the constructed measurement system.
Research on Energy Storage Capacity Planning Model Considering Peak Regulation Gap
Authors: Yuan Jiandang , Gu Ming , Bai Xiaolei , Yang Kui
Published: March 2021

Establishing a clean energy-based power supply model and realizing energy structure adjustment are currently important directions for energy development in various parts of China. Realizing the cleanness of urban energy structures depends on large-scale energy storage technologies. Therefore, the rational planning of long-term and short-term energy storage plans in the region is of great significance to guide the development of urban energy storage and further realize the cleanness of urban energy structure. In this context, this paper considers the peak shaving gap and establishes a wide range of energy storage capacity planning models. Urumqi is used as an example city to develop a regional planning plan using the above model. An example validates the effectiveness of the model.