bluuebunny/crossref_metadata_2025 huggingface dataset:
Die verschiedenen Belastungsformen − Fahrrad, Laufband, Adenosin, Regadenoson und Dobutamin. Vor- und Nachteile?
Authors: Gatterer Constantin , Graf Senta
Published: February 2020

In der folgenden Übersicht sollen die verschiedenen Belastungsformen sowie deren Indikationen und Kontraindikation beschrieben werden. Zur Beurteilung, ob eine hämodynamisch wirksame koronare Herzkrankheit vorliegt bzw. ob eine Koronargefäßstenose hämodynamisch auch signifikant ist, dient die Myokardszintigrafie unter Belastung, welche dann der Ruheuntersuchung gegenübergestellt wird. Die Untersuchung ist allerdings nur dann auch aussagekräftig, wenn eine entsprechende Belastung der Applikation des Radiopharmakons vorausgegangen ist. Dies setzt voraus, dass die Belastung – ergometrisch oder pharmakologisch – adäquat durchgeführt wurde. Es muss der Blutfluss unter physiologischen Bedingungen bei Belastung auf das 3 – bis 4-Fache ansteigen. Dies ist das Ziel der Belastung, deren unterschiedliche Formen in der Folge beschrieben werden 1.
Das heilsame Herz
Authors: Findeisen Peter
Published: February 2020

Wohlwollen, Präsenz, Liebe: Qualitäten des Herzens in der Therapie und wie wir sie entwickeln und verwirklichen können.
Assessment of the scientific evidence of the potential use of açaí (Euterpe oleracea, Mart.) in clinical outcomes: analysis with focus on antioxidant and anti-inflammatory action
Authors: Figueiredo A M , Biernet I RC
Published: February 2020

The açaí berry (Euterpe oleracea, Mart.), fruit native to the Amazon region and explored mainly in the region of Pará, gained importance in recent years due to potential health benefits, associated with its phytochemical composition and antioxidant capacity, related to its high content of flavonoids. Among these, anthocyanins are responsible for the anti-inflammatory and antioxidant capacity of this fruit. Experimental studies show that due to its composition, the acai berry has antioxidant activity related to its ability to reduce the reactive oxygen species (ROS) and its potential to inhibit cyclooxygenase 2 (COX-2). Another benefit studied is the analysis of their effectiveness in the anti-inflammatory process, being observed inhibition of araquedônico acid-derived mediators, suggesting that the fruit can act in the chronic inflammatory process. Also it was possible to observe that the fruit may have anti-inflammatory effects in healthy patients. Thus, the supplementation of diets with use of acai berry could attenuate inflammation process and oxidative stress, today with more consistent evidence derived primarily from in vitro studies. However, there is still need for further studies to prove the action of this fruit in the mechanisms involved in these processes, isolation of specific compounds and determining their optimal dosage.
Nanoscale magnetophotonics
Authors: Maccaferri Nicolò , Zubritskaya Irina , Razdolski Ilya , Chioar Ioan-Augustin , Belotelov Vladimir , Kapaklis Vassilios , Oppeneer Peter M. , Dmitriev Alexandre
Published: February 2020

This Perspective surveys the state-of-the-art and future prospects of science and technology employing nanoconfined light (nanophotonics and nanoplasmonics) in combination with magnetism. We denote this field broadly as nanoscale magnetophotonics. We include a general introduction to the field and describe the emerging magneto-optical effects in magnetoplasmonic and magnetophotonic nanostructures supporting localized and propagating plasmons. Special attention is given to magnetoplasmonic crystals with transverse magnetization and the associated nanophotonic non-reciprocal effects and to magneto-optical effects in periodic arrays of nanostructures. We also give an overview of the applications of these systems in biological and chemical sensing, as well as in light polarization and phase control. We further review the area of nonlinear magnetophotonics, the semiconductor spin-plasmonics, and the general principles and applications of opto-magnetism and nano-optical ultrafast control of magnetism and spintronics.
First-principles investigation of the intrinsic defect-related properties in Mo2GeC
Authors: Shao YaPing , Zhao Daqiang , Duan Wenshan
Published: February 2020

As one of the MAX phases, Mo2GeC can also be considered as a potential material for use in next generation fission and fusion program reactors. We used first-principles calculations to investigate the formation energies, stable configuration, and interatomic bonding of intrinsic defects (mono-vacancy, self-interstitials, antisites, and Frenkel pairs). For all intrinsic defects, only the value of the formation energy for the C vacancy defect is negative, and the biggest formation energy occurs for GeFP. The existence of mono-vacancy shrinks the Mo2GeC structure, while the existence of interstitials, antisites, and Frenkel pair defects expands the Mo2GeC structure. In order to further illustrate the stability of defects, we calculated the DOS and PDOS of defects. We can find that defects have a certain effect on the density of states of Mo2GeC. When mono-vacancy and antisite defects are generated, the DOS at the Fermi level decreased, while the production of self-interstitials and Frenkel defects caused the DOS at the Fermi level to increase. We also found that the C vacancy, Ci1, and Mo–Ge antisite pair caused a small pseudo-gap energy at the Fermi level, indicating that their structure is relatively stable, which is consistent with the result of low formation energy. In addition, a small isolated peak at the point of −13.5 eV for Ci1 appeared, which is attributed to the C-2s orbital. We hope that our results could provide theoretical guidance for future experiments and applications of Mo2GeC.
Non-Markovian models of environmentally-driven disentanglement in molecular charge qubits
Authors: Zhou Shengyang , Blair Enrique P.
Published: February 2020

Models of quantum disentanglement are developed for nanometer-scale molecular charge qubits (MCQs). Two MCQs, A and B, are prepared in a Bell state and separated for negligible A–B interactions. Interactions between the local environment and each MCQ unravels A–B entanglement during coherent system+environment evolution. Three models are used for dynamics: (1) a previously developed numerical model, in which both AB and environment E are modeled explicitly; (2) an exact, semi-analytic model, in which only the dynamics of AB are calculated, and (3) an approximate model developed from the semi-analytic model and assumptions about randomness in E. In the approximate model, the non-zero coherences of the density operator for AB decay with a Gaussian time dependence. This provides a time scale for system dynamics in the exact models as well. This time scale is related directly to the strength of AB–E interaction. This time scale describes cases where environmental interaction with one target MCQ is dominant, generalizing a previous time scale applicable only when both MCQs have roughly the same strength of interaction with the local environment. Entanglement is measured using two-qubit correlation functions, the dynamics of which are used to demonstrate the effectiveness of the time scale. The early-time decay of coherences and the loss of entanglement are well-characterized as Gaussian, a behavior that Markovian models for memoryless environments cannot capture. The approximate Gaussian model may be used to describe the dynamics of MCQ disentanglement under the influence of environments modeled here, as well as other environments where randomness is present.
Numerical simulation and validation of subsurface modification and crack formation induced by nanosecond-pulsed laser processing in monocrystalline silicon
Authors: Kiyota H. , Hara K. , Jankowski M. , Fejer M. M.
Published: February 2020

We describe a numerical simulation of subsurface modification and crack formation in monocrystalline silicon induced by nanosecond-pulsed laser irradiation. In this model, we assume the residual stress generation due to material transfer caused by volume reduction during melting and resolidification to be the dominant factor in creating subsurface mechanical stress and cracks. In order to quantitatively determine the geometry of the modified region, we numerically model the nonlinear propagation and absorption of the laser beam and the thermal transport. We find that during a single pulse, the lattice temperature distribution results in melting, material transfer, and structural changes on resolidification. The residual stress generated within the monocrystal adjacent to the modified region is subsequently assessed for crack formation in the substrate. The validity of the proposed model is confirmed through agreement with a number of experimental results, including the transmitted power, the timing of the onset of the phase transition during laser irradiation, the processing threshold, the geometry of the modified region, and the formed crack length.
SANS and X-ray studies of the structural transitions in impurity-helium gel samples
Authors: Efimov V. B. , Mezhov-Deglin L. P. , Rybchenko O. G.
Published: February 2020

This article presents the results of SANS studies on the structure of nanocluster impurity gel samples, and X-ray observations of the structural transformations in amorphous powders obtained during the decay of heated gel samples. The possibilities of using these methods to determine the state and structural transitions of these substances are discussed.
Studies of nuclear polarization of hydrogen atoms embedded in solid molecular hydrogen and hydrogen deuteride films
Authors: Sheludiakov S. , Lee D. M. , Khmelenko V. V. , Ahokas J. , Järvinen J. , Vasiliev S.
Published: February 2020

We report on an electron-spin resonance study of nuclear polarization of hydrogen atoms embedded in solid H2 and HD films at temperatures 0.1–1.5 K and in a high magnetic field of 4.6 T. Similar to our previous work [Phys. Rev. Lett. 122, 225301 (2019)], we observed a build-up of the spontaneously (p≃0.35) and highly (p≃0.75) nuclear polarized phases of H atoms in the as-deposited H2 films. However, we did not obtain an enhanced nuclear polarization of H atoms in the regions of their small local concentration. We also failed to observe enhanced nuclear polarization for H atoms in the annealed H2 films as well as in the as-deposited HD sample. These observations tend to support our previous explanation for the build-up of high nuclear polarization due to the formation of weakly-bound triplet H2 molecules.
The effect of sorption of air and hydrogen components on the structural characteristics of superconducting FeTe0.65Se0.35 single crystals
Authors: Prokhvatilov A. I. , Meleshko V. V. , Bondarenko S. I. , Koverya V. P. , Wiśniewski A.
Published: February 2020

X-ray studies of iron chalcogenide FeTe0.65Se0.35 single crystals were performed after they were exposed in air and hydrogen atmospheres at room and high temperatures, for long periods of time. It is found that impurity components have a significant effect on the structural characteristics of the diffraction pattern for this layered tetragonal superconducting material. It is shown that molecular impurities do not change the matrix symmetry of the tetragonal substitution solutions. However, when hydrogen molecules dissociate close to 200 °C under the thermocatalytic effect of Fe atoms, the tetragonal lattice of the matrix becomes unstable. Symmetry is reduced against the background of an increased concentration of atomic hydrogen and strengthening of the chemical bonds in the crystals. The crystal density sharply increases, and a FeTe0.65Se0.35 + H interstitial solution based on an orthorhombic lattice is formed. It is shown that the structural tetra-ortho phase transition in such solutions occurs near 200 °C.
One Health: the global challenge of Clostridium difficile infection
Authors: Lim Su-Chen , Riley Thomas V , Knight Daniel R
Published: February 2020

The One Health concept recognises that the health of humans is interconnected to the health of animals and the environment. It encourages multidisciplinary communication and collaboration with the aim of enhancing surveillance and research and developing integrative policy frameworks. Clostridium difficile (also known as Clostridioides difficile) infection (CDI) has long been viewed as a hospital-associated (HA) enteric disease mainly linked to the use of broad-spectrum antimicrobials that cause dysbiosis in the gut and loss of ‘colonisation resistance'. However, since the early 2000s, the rate of community-associated CDI (CA-CDI) has increased to ~15% in Europe, ~30% in Australia and ~40% in the USA in populations often without obvious risk factors. Since the 1990s, it has become apparent that food animals are now a major reservoir and amplification host for C.difficile, including lineages of clinical importance. Cephalosporin antimicrobials, to which C. difficile is intrinsically resistant, were licensed for animal use in North America in 1990. By the second decade of the 21st century, there were reports of C. difficile contamination of food and the environment in general. Using whole-genome sequencing (WGS) and high-resolution typing, C. difficile isolates from humans, animals, food and the environment were proven to be genetically closely related and, in some cases, indistinguishable. This suggests possible zoonoses and/or anthroponoses, with contaminated food and the environment acting as the conduit for transmission between animals and humans. This paper summarises the key evidence that demonstrates the One Health importance of C. difficile.
Antibiotic pollution and risk assessment under different cultivation modes in aquaculture ponds of the Taihu Lake Basin, China
Authors: Yan Yan , Deng Yang , Ji Min , Xu Xiaoguang , Zhang Limin , Wang Guoxiang
Published: February 2020

Although antibiotics are widely used in aquaculture ponds, their environmental fates and ecological risks are still not fully understood. In this study, the occurrence and spatial distribution of antibiotics in 10 aquaculture ponds, using three different cultivation modes, were investigated in Taihu Lake Basin, China. In total, 10 antibiotics belonging to four classes were measured. Sulfonamides were the most prevalent, with the concentration of sulfamethoxazole being the highest at 426.53μg L–1; all other antibiotic concentrations ranged from undetectable to 132.83μg L–1. There were significant differences in total antibiotic burdens among different regions, including in sulfonamides, fluoroquinolones, macrolides and tetracyclines. There were also differences among cultivation modes; antibiotics were most abundant in fish ponds, which had concentrations an order of magnitude higher than those in crab and crab–shrimp ponds. Results of risk-quotient (RQ) analysis indicated that all of the antibiotics, expect roxithromycin, posed a high risk to algae, with the values exceeding 1. These findings suggest that the reasonable control of antibiotic usage is necessary to preserve human safety and the health of the aquatic ecosystem.
Can native-speaker corpora help explain L2 acquisition of tense and aspect?
Authors: Tracy-Ventura Nicole , Cuesta Medina Jhon A.
Published: February 2020

This study investigates the distributional patterns of verb form frequencies in the Spanish past tense (the Preterit and the
Imperfect) in the Corpus del Español (Davies, 2002). Following
a usage-based approach, we examine the potential influence of input frequency as a driving factor in L2 learning. Results
provide support for the existence of a distributional bias in L1 Spanish, with several telic predicates more often occurring
in the Preterit and several atelic predicates in the Imperfect. Results also demonstrate that the distribution of verbs in the
Preterit and the Imperfect is Zipfian, with the most frequent verbs overall accounting for the majority of all the tokens.
Finally, an analysis of the different meanings of the Imperfect demonstrates clear differences in frequency of use with the
continuous meaning as the most frequently expressed meaning, followed by habituality and progressivity. Implications for
research and teaching are discussed.
Russian spoken discourse
Authors: Kibrik Andrej A. , Korotaev Nikolay A. , Podlesskaya Vera I.
Published: February 2020

We previously developed an approach to spoken Russian monologic
discourse, and are now extending that, looking primarily at interactional multi-party
discourse, contextualizing speech phenomena as multichannel (multimodal) communication. The
evidence analyzed is the Russian Pear Chats and Stories corpus, see . Scores
transcripts are introduced to annotate the interlocutors’ shared time line, including
periods of silence. The elementary discourse unit (EDU) is posited as a central building
block of local discourse structure. Canonical EDUs coincide with clauses; additionally,
subclausal, superclausal, and paraclausal EDUs are found. Prosodic phenomena are considered;
EDUs and groups of EDUs are accounted through a discourse-semantic category of phase.
Disfluencies and other structural phenomena are systematically treated. Conventions of
discourse transcription capture both prosodic and functional aspects of discourse.
Prosody and the organization of information in Central Pomo, a California indigenous
language
Authors: Mithun Marianne
Published: February 2020

In some theoretical frameworks, it is assumed that prosodic
structure is a direct reflection of syntactic structure. Close examination of unscripted
speech confirms that though the two often work in concert, they are distinct. Prosodic
structure differs from grammatical structure in some fundamental ways. Prosody (pitch,
intensity, rhythm) involves continua and can be more responsive to certain subtle
differences in cognitive state, discourse context, and interactive goals. Grammar
(morphology and syntax) can mark more distinctions, but these are categorical and
conventionalized: an affix is either present or absent; one constituent either precedes or
follows another. Here some prosodic structures, their functions, and their relation to
grammatical structures are discussed with examples from Central Pomo, a language indigenous
to Northern California.
The pragmatic analysis of speech and its illocutionary classification according to the
Language into Act Theory
Authors: Cresti Emanuela
Published: February 2020

According to the Language into Act Theory, reference units in
speech have a pragmatic nature: they correspond to the activation of sensory-motor schemas
leading to the performance of different speech acts. Our background is the affective and
psychic motivations of the Human Birth Theory (Fagioli, 1971), compatible
with recent theories of Embodied Cognition. Identification and
classification of speech acts rest on corpus-based research. Speech activity is encoded by
prosody, that conveys utterance boundaries, illocutionary force and
information structure. The utterance nucleus is the
Comment, responsible for illocutionary force. We illustrate the
methodology for the induction of illocutions from corpora and detail pragmatic and prosodic
features which allow classifying illocutionary types. A case study is presented for four
original illocutions (self-conclusion, assertion taken for granted, ascertainment,
evidentiality assertion).
Illocution as a unit of reference for spontaneous speech
Authors: Bossaglia Giulia , Mello Heliana , Raso Tommaso
Published: February 2020

In this paper we propose a synchronic, corpus-based account of
insubordination, through the analysis of adverbial clauses in Brazilian Portuguese
spontaneous speech at the syntax/prosody interface. The segmentation of the speech flow
through prosodic cues is crucial to analyse linguistic and, specifically, syntactic
relations in spoken language. Besides, it is through prosody that illocutionary and
informational values are conveyed in speech. Our claim is that insubordination can be
studied without assuming the existence of a grammaticalization path or main clause ellipsis
processes, given that through specific illocutionary prosodic profiles, syntactically
dependent clauses are assigned pragmatic autonomy.
Structural improvement of LidNA: delta-type LidNA is a potent miRNA inhibitor constructed with unmodified DNA
Authors: Tachibana Akira , Komeda Yoshiki , Yamamoto Aiko
Published: February 2020

Many miRNA inhibitors have been developed, including chemically modified oligonucleotides, such as 2′-O-methylated RNA and locked nucleic acid (LNA). Unmodified DNA has not yet been reported as a miRNA inhibitor due to relatively low DNA/miRNA binding affinity. We designed a structured DNA, LidNA, which was constructed with unmodified DNA, consisting of a complementary sequence to the target miRNA flanked by two structured DNA regions, such as double-stranded DNA. LidNA inhibited miRNA activity more potently than 2′-O-methylated RNA or LNA. To optimize LidNA, two double-stranded regions were joined, causing the molecule to assume a delta-like shape, which we termed delta-type LidNA. Delta-type LidNAs were developed to target endogenous and exogenous miRNAs, and exhibited potent miRNA inhibitory effects with a duration of at least 10 days. Delta-type LidNA-21, which targeted miR-21, inhibited the growth of cancer cell lines. This newly developed LidNA could contribute to miRNA studies across multiple fields.

Abbreviations: LidNA: DNA that puts a lid on miRNA function; LNA: locked nucleic acid; 3′-UTR: 3′-untranslated regions; RISC: RNA-induced silencing complex; MBL: Molecular beacon-like LidNA; YMBL: Y-type molecular beacon-like LidNA; TDMD: target-directed microRNA degradation.
Dorsal muscle fatigue increases thoracic spine curvature in all‐out recreational ergometer rowing
Authors: Willwacher Steffen , Koopmann Till , Dill Stephan , Kurz Markus , Brüggemann Gert‐Peter
Published: February 2020

The purpose of this study was to investigate fatigue‐related changes in spinal kinematics, kinetics, and muscle activity of back muscles during a 2000 m all‐out ergometer rowing performance. We analyzed ten male subjects with experience in both rowing and CrossFit exercises. We applied a novel kinematic method to describe spine curvature, determined bending moments at the spine using inverse dynamics and collected EMG data. We identified significant increases in spine curvature of the thoracic spine (i.e. vertebrae Th6 to Th11). Significant increases in peak moments were found only at the upper spine (i.e. Th2). We found no significant changes in EMG amplitudes, while the frequency analysis showed significant decreases in the mean frequencies (MNF) for the M. latissimus dorsi, the M. trapezius descendens and the M. deltoideus posterior. No significant changes on MNF were found for the Mm. erector spinae. We hypothesize that the significant increase in curvature for the thoracic spine is connected to the fatigued back muscles, especially the Mm. trapezius descendens, and might lead to an unbalanced loading of intervertebral discs and other structures. These findings are particularly important for athletes and coaches in CrossFit as strenuous rowing intervals are combined with technical exercises with high loads on the back and spine (e.g. power and Olympic lifting) leading to impaired muscular stabilization and potentially to an increased injury risk.
The benefit of computational modelling in physics teaching: a historical overview
Authors: Weber Jannis , Wilhelm Thomas
Published: February 2020

Computational modelling is not only an important element in scientific research, it also has a rich history in physics education and its application in the classroom has changed greatly over the last few decades. To explain why computational modelling is used in physics education, we discuss its use in teaching and the benefits to the teaching and learning process. Secondly, historical developments are highlighted, and different methods of computational modelling are discussed in more detail, developing the desired features of modern software for classroom computational modelling. A review of the research in this field was conducted, showing what is known about the effects of computational modelling on students’ conceptual understanding, systemic thinking, views about nature of science and interest in physics, among others variables. Derived from the research results, recommendations are given about the use of computational modelling in physics education and research recommendations are presented with the goal to better understand the interaction between the student and computational modelling process.
Hematite coated, conductive Y doped ZnO nanorods for high efficiency solar water splitting
Authors: Commandeur Daniel , McGuckin Joshua , Chen Qiao
Published: February 2020

For the first time, hematite (α-Fe2O3) crystals were electrochemically deposited over vertically aligned conductive zinc oxide nanorods (NR) to form a specially designed 3D heterostructure with a unique triple layer structure. The structure formed with a thin layer of ZnFe2O4 sandwiched between the hematite and the ZnO, which forms a barrier to reduce the back migration of holes. Hence, the charge separation is significantly improved. The small unequal bandgaps of α-Fe2O3 and ZnFe2O4 help to enhance and broaden visible light absorption. The electron transportation was further improved by yttrium doping in the ZnO (YZnO) NRs, resulting in increased conductivity. This allowed the vertically aligned NRs to perform as electron highways, which also behave as effective optical waveguides for improved light trapping and absorption, since ZnO absorbs little visible light. All these benefits made the unique structures suitable for high performance photoelectrochemical (PEC) water splitting. Optimisation of α-Fe2O3 thickness led to a photocurrent density improvement from 0.66 to 0.95 mA cm−2 at 1.23 VRHE. This was further improved to 1.59 mA cm−2 by annealing at 550 °C for 3 h, representing a record-breaking photocurrent for α-Fe2O3/ZnO systems. Finally IPCE confirmed the successful generation and transfer of photoelectrons under visible light excitation in the specifically designed heterostructure photoanode, with 5% efficiency for blue light, and 15% for violet light.
Effect of attenuation mismatches in time of flight PET reconstruction
Authors: Emond Elise C , Bousse Alexandre , Machado Maria , Porter Joanna , Groves Ashley M , Hutton Brian F , Thielemans Kris
Published: February 2020

While the pursuit of better time resolution in positron emission tomography (PET) is rapidly evolving, little work has been performed on time of flight (TOF) image quality at high time resolution in the presence of modelling inconsistencies. This works focuses on the effect of using the wrong attenuation map in the system model, causing perturbations in the reconstructed radioactivity image. Previous work has usually considered the effects to be local to the area where there is attenuation mismatch, and has shown that the quantification errors in this area tend to reduce with improved time resolution. This publication shows however that errors in the PET image at a distance from the mismatch increase with time resolution. The errors depend on the reconstruction algorithm used. We quantify the errors in the hypothetical case of perfect time resolution for maximum likelihood reconstructions. In addition, we perform reconstructions on simulated and patient data. In particular, for respiratory-gated reconstructions from a wrong attenuation map, increased errors are observed with improved time resolutions in areas close to the lungs (e.g. from 13.3% in non-TOF to up to 20.9% at 200 ps in the left ventricle).
Experimental quantification of four-photon indistinguishability
Authors: Giordani Taira , Brod Daniel J , Esposito Chiara , Viggianiello Niko , Romano Marco , Flamini Fulvio , Carvacho Gonzalo , Spagnolo Nicolò , Galvão Ernesto F , Sciarrino Fabio
Published: February 2020

Photon indistinguishability plays a fundamental role in information processing, with applications such as linear-optical quantum computation and metrology. It is then necessary to develop appropriate tools to quantify the amount of this resource in a multiparticle scenario. Here we report a four-photon experiment in a linear-optical interferometer designed to simultaneously estimate the degree of indistinguishability between three pairs of photons. The interferometer design dispenses with the need of heralding for parametric down-conversion sources, resulting in an efficient and reliable optical scheme. We then use a recently proposed theoretical framework to quantify four-photon indistinguishability, as well as to obtain bounds on three unmeasured two-photon overlaps. Our findings are in high agreement with the theory, and represent a new resource-effective technique for the characterization of multiphoton interference.
Quantum compression of tensor network states
Authors: Bai Ge , Yang Yuxiang , Chiribella Giulio
Published: February 2020

We design quantum compression algorithms for parametric families of tensor network states. We first establish an upper bound on the amount of memory needed to store an arbitrary state from a given state family. The bound is determined by the minimum cut of a suitable flow network, and is related to the flow of information from the manifold of parameters that specify the states to the physical systems in which the states are embodied. For given network topology and given edge dimensions, our upper bound is tight when all edge dimensions are powers of the same integer. When this condition is not met, the bound is optimal up to a multiplicative factor smaller than 1.585. We then provide a compression algorithm for general state families, and show that the algorithm runs in polynomial time for matrix product states.
Is oxidation of atmospheric mercury controlled by different mechanisms in the polluted continental boundary layer vs. remote marine boundary layer?
Authors: Gabay Maor , Raveh-Rubin Shira , Peleg Mordechai , Fredj Erick , Tas Eran
Published: February 2020

Deposition of atmospheric mercury is of global concern, primarily due to health effects associated with efficient bioaccumulation of mercury in marine food webs. Although oxidation of gaseous elementary mercury (GEM), the major fraction of atmospheric mercury, is a critical stage in regulating atmospheric mercury deposition efficiency, this oxidation is currently not well-characterized, limiting modeling-based assessments of mercury in the environment. Based on a previous study, we hypothesized that the oxidation of GEM is predominantly controlled by multistep bromine- and chlorine-induced oxidation (MBCO) in the remote marine boundary layer (RMBL), and by photochemical smog oxidants, primarily ozone (O3) and hydroxyl radical (OH), in the polluted continental boundary layer (PCBL). To test this hypothesis, we used the following analyses: (i) application of a newly developed criterion to evaluate the gaseous oxidized mercury (GOM)–O3 association based on previous studies in the RMBL and PCBL; (ii) measurement-based box simulations of GEM oxidation in the RMBL and at a PCBL site; and (iii) measurement-based analysis of photochemical oxidation vs. other processes which potentially influence GOM. Our model simulations indicated that the MBCO mechanism can reproduce GOM levels in the RMBL, but not in the PCBL. Our data analysis suggested the important role of photochemical smog oxidants in GEM oxidation in the PCBL, potentially masked by the effect of relative humidity and entrainment of free tropospheric air.
Metal oxide semiconductor-based Schottky diodes: a review of recent advances
Authors: Al-Ahmadi Noorah A
Published: February 2020

Metal-oxide-semiconductor (MOS) structures are essential for a wide range of semiconductor devices. This study reviews the development of MOS Schottky diode, which offers enhanced performance when compared with conventional metal-semiconductor Schottky diode structures because of the presence of the oxide layer. This layer increases Schottky barrier heights and reduced leakage currents. It also compared the MOS and metal-semiconductor structures. Recent advances in the development of MOS Schottky diodes are then discussed, with a focus on aspects such as insulating materials development, doping effects, and manufacturing technologies, along with potential device applications ranging from hydrogen gas sensors to photodetectors. Device structures, including oxide semiconductor thin film-based devices, p-type and n-type oxide semiconductor materials, and the optical and electrical properties of these materials are then discussed with a view toward optoelectronic applications. Finally, potential future development directions are outlined, including the use of thin-film nanostructures and high-k dielectric materials, and the application of graphene as a Schottky barrier material.
Thermoelastic interactions in a hollow cylinder due to a continuous heat source without energy dissipation
Authors: Zenkour Ashraf M , Kutbi Marwan A
Published: February 2020

The linear generalized Green–Naghdi thermoelasticity theory without energy dissipation is employed. The study of thermoelastic interactions in a hollow cylinder under a continuous heat source is carried out. Firstly, Laplace and Hankel transforms are employed to solve the problem without the time domain. Then, the state space approach is employed to get the exact solution of the problem in the space domain. Once again, the inverse Laplace transforms is used to get the solutions in the time domain. Accurate terminologies for the temperature, thermoelastic potential, axial displacement, dilatation, and stresses are derived. Numerical outcomes for field variables are presented with the view of illustrating the theoretical results.
The synthesis of urchin-like γ-Al2O3 hierarchical microspheres from Al foils and its rapid adsorption ability towards Congo red
Authors: Feng Kaizhong , An Jie , Ren Weian , Lei Xiaoling , Li Gaoying , Rong Daoqing , Wen Xiaogang
Published: February 2020

In this paper, we present a convenient hydrothermal method to synthesize hierarchical microspheres consisting of ammonium aluminum carbonate hydroxide (AACH) nanowires with a diameter of about 400 nm and length ∼50 μm on aluminum foils. After calcination at 900 °C, hierarchical γ-Al2O3 microspheres with mesoporous structures were obtained successfully, which possess a high specific surface area of 124 m2 g−1 and high porosity of 0.71cm3 g−1. The possible formation mechanism was discussed. The as-prepared mesoporous γ-Al2O3 hierarchical nanostructures exhibited improved adsorption performance towards Congo red in aqueous solution, 90% CR could be removed rapidly in 20 min, and its saturation adsorption capacity in 80 mg l−1 Congo red can reach to 180 mg g−1, it suggests that the hierarchical γ-Al2O3 microspheres with unique microstructure have potential in wastewater treatment.
Preparation of nanocellulose from steam exploded poplar wood by enzymolysis assisted sonication
Authors: Zhang Yue , Chen Jienan , Zhang Lin , Zhan Peng , Liu Na , Wu Zhiping
Published: February 2020

By exploiting cellulose nanofibril’s high aspect ratio and nano-order-unit interconnected web-like structure of poplar wood, a new approach was designed. Steam explosion was used for the pretreatment of the poplar, followed by enzymatic hydrolysis assisted sonication for the preparation of nanocellulose. The effects the cellulase dosage, enzymatic hydrolysis time and temperature on the yield of nanocellulose were studied. Under optimal conditions nanocellulose yield was approximately 13.2%. The chemical composition, crystallinity, and morphology of the composites were characterised using FT-IR, x-ray diffraction and TEM. The results demonstrated that the structure was not destroyed during the preparation process, that the crystal form remained cellulose I, and the crystallinity was 61.98%, 9.15% higher than that of poplar cellulose. The width was between 20 and 50 nm, with high aspect ratio and a web-like entangled structure. Therefore, nanocellulose prepared using this method is an ideal toughening material that could be applied in composite materials.
A high quality surface finish grinding process to produce total reflection mirror for x-ray fluorescence analysis
Authors: Ohmori Hitoshi , Umezu Shinjiro , Kim Yunji , Uehara Yoshihiro , Kasuga Hiroshi , Kato Teruko , Itoh Nobuhide , Kurokawa Syuhei , Kusumi Takayuki , Sugawara Yugo , Kunimura Shinsuke
Published: February 2020

Total reflection x-ray fluorescence analysis is applied to trace element detection in liquid for effective environmental monitoring. This analytical approach requires x-ray total reflection mirrors. In order to achieve high sensitivity element detection, the mirrors require high surface quality for high x-ray reflectivity. Surface finishing for x-ray mirrors is typically conducted through a series of abrasive processes, such as grinding and polishing, and is thus time consuming. The purpose of this study is to streamline and enhance the surface finishing process based on unique high quality grinding techniques for the production of x-ray total reflection mirrors.
Effects of laser scanning strategies on selective laser melting of pure tungsten
Authors: Gu Dongdong , Guo Meng , Zhang Hongmei , Sun Yixuan , Wang Rui , Zhang Lei
Published: February 2020

Three types of scanning strategies, including the chessboard scanning strategy, the zigzag scanning strategy and the remelting scanning strategy, were conducted to study the effects of scanning strategies on surface morphology, microstructure, mechanical properties and the grain orientation of selective laser melted pure tungsten. The results showed that the pores and cracks were main defects in SLM-processed tungsten parts. The pores could be eliminated using the remelting scanning strategy. However, the cracks seemed to be inevitable regardless of the applied scanning strategies. The microstructures of SLM-processed tungsten were columnar grains and showed strong epitaxial growth along the building direction. A compressive strength of 923 MPa with an elongation of 7.7% was obtained when the zigzag scanning strategy was applied, which was the highest among the three scanning strategies. By changing the scanning strategies, the texture of SLM-processed tungsten in the direction of processing could be changed.
Perspective: new insights from loss function landscapes of neural networks
Authors: Chitturi Sathya R , Verpoort Philipp C , Lee Alpha A , Wales David J
Published: February 2020

We investigate the structure of the loss function landscape for neural networks subject to dataset mislabelling, increased training set diversity, and reduced node connectivity, using various techniques developed for energy landscape exploration. The benchmarking models are classification problems for atomic geometry optimisation and hand-written digit prediction. We consider the effect of varying the size of the atomic configuration space used to generate initial geometries and find that the number of stationary points increases rapidly with the size of the training configuration space. We introduce a measure of node locality to limit network connectivity and perturb permutational weight symmetry, and examine how this parameter affects the resulting landscapes. We find that highly-reduced systems have low capacity and exhibit landscapes with very few minima. On the other hand, small amounts of reduced connectivity can enhance network expressibility and can yield more complex landscapes. Investigating the effect of deliberate classification errors in the training data, we find that the variance in testing AUC, computed over a sample of minima, grows significantly with the training error, providing new insight into the role of the variance-bias trade-off when training under noise. Finally, we illustrate how the number of local minima for networks with two and three hidden layers, but a comparable number of variable edge weights, increases significantly with the number of layers, and as the number of training data decreases. This work helps shed further light on neural network loss landscapes and provides guidance for future work on neural network training and optimisation.
Anthology
Authors: Grant Ben
Published: February 2020

Anthologies, in the broadest sense of collections of independent texts, have always played an important role in preserving and spreading the written word, and collections of short forms, such as proverbs, wise sayings, and epigraphs, have a long history. The literary anthology, however, is of comparatively recent provenance, having come to prominence only during the long 18th century, when the modern concept of “literature” itself emerged. Since that time, it has been a fundamental part of literary culture: not only have literary texts been published in anthologies, but also the genre of the anthology has done much to shape their form and content, and to influence the ways in which they are read and taught, particularly as literary criticism has developed in tandem with the rise of the anthology. The anthology has also stimulated innovation in many periods and places by providing a model for writers of different genres of literature to emulate, and it has been argued that the form of the novel is much indebted to the anthology. This is connected to its close association with the figure of the reader. Furthermore, anthologies have helped to define what literature is, and been crucial to the canonization of texts, authors, and genres, and the consolidation of literary traditions. It is therefore not surprising that they were at the heart of the theoretical and pedagogical debates within literary studies known as the canon wars, which raged during the 1980s and 1990s. In this role, they contributed much to discussions concerning the theories and politics of identity, and to such approaches as feminism and race studies. The connection between the anthology and literary theory extends beyond this, however: theory itself has been subject to widespread anthologization, which has affected its practice and reception; the form of theoretical writing can in certain respects be understood as anthological; and the anthology is an important object of theoretical attention. For instance, given the potential which the digital age holds to transform how texts are disseminated and consumed, and the importance of finding ways to classify and navigate the digital archive, anthology studies is likely to figure largely in the Digital Humanities.
Indigenous Manuscripts of Ancient and Early Colonial Mesoamerica: 13th–16th Centuries
Authors: Afanador-Pujol Angélica J.
Published: February 2020

In the area known as Mesoamerica (Mexico, Guatemala, parts of El Salvador, Honduras, and Belize), indigenous writers between the 13th and 16th centuries produced manuscripts using both pictographic and alphabetic-based texts. They worked closely with noble and priestly elites to meticulously design and paint manuscripts. Before the arrival of Europeans, writers worked on a variety of media, from animal hide and textiles to paper. They folded long sheets into accordion-like manuscripts, covered them in a lime plaster, and, using rich natural pigments, recorded complex writing systems. These books contained historical, religious, political, scientific, and cultural knowledge. They not only recorded information, but guided the lives of individuals and communities. Only fourteen of these manuscripts are known to survive, as Spanish conquistadors and friars destroyed the vast majority of them in their effort to eradicate indigenous religions during the conquest of the region in the 16th century.

In the years following the Spanish invasion, Mesoamerican artists and scribes had to adapt to new demands from their indigenous patrons, the viceregal government, and the Catholic church. They learned to use the European alphabet and artistic conventions to produce new materials containing ethnographic, religious, and historical information. In addition, they transcribed and wrote speeches, songs, and poems, and produced legal documents to fight for their own rights and those of their communities, rulers, and patrons. Modern-day scholars have made great strides deciphering pre-Columbian writing systems and understanding the make, medium, and function of manuscripts. The vast corpus of colonial-era manuscripts has also been a productive field for understanding Mesoamerican thought, cultural practices, and the social and political forces that shaped colonial life and its literary production.
Warfare and Latina/o Social Movements
Authors: Rincón Belinda Linn
Published: February 2020

Despite receiving little to no attention in mainstream academic scholarship about US antiwar movements, Latina/o communities have a long history of protesting wars and military interventions throughout the second half of the 20th century. The wide-scale mobilization of Latina/o protestors against the US war in Vietnam marks an important development in Latina/o social movement history. Another important moment of Latina/o mobilization came in the 1980s and 1990s in response to the mass influx of refugees fleeing war in Central America that resulted in large part from US interventions in Central American civil wars. The historical context, political struggles, and modes of activism of the Central American solidarity movement distinguish it from the Vietnam antiwar movements. Yet, like earlier Chicana/o and Puerto Rican antiwar movements, there remained a concerted focus on transnational solidarity. Notably, each movement accompanied a literary and cultural renaissance in which authors and activists—and, in many cases, author-activists—joined forces to protest the political, economic, and social consequences of warfare. Some even joined revolutionary movements as internationalist volunteers. Latina/o activists and authors have drawn on rich oral, musical, and folkloric traditions and tropes to create new modes of expression and political speech. To fully account for the multiple forms of Latina/o antiwar expression, it is necessary to look beyond traditional literary genres and include protest speeches, agit-prop theater, movement manifestos and newspapers, conference resolutions, handbills, political pamphlets, corridos (ballads), oral histories, induction refusals, and testimonios, among other documents. Through alternative print cultures, Latina/o antiwar activists and authors created a space to summon and address a Latina/o readership whose concerns over war were largely ignored in mainstream publics. Latina/o authors also insisted on creative autonomy and aesthetic sophistication while remaining resolutely committed to producing socially relevant literature whose resonance extended far beyond the page. Such characteristics define a diverse body of Latina/o writing that helped galvanize Latina/o antiwar movements.
Latino Gay Literature
Authors: Contreras Daniel
Published: February 2020

Who are we when we read queer Latinx literature? It may be helpful in approaching this topic to think about what we mean by America along with what we mean by Latinx, or Latina/o, and Latin American. Some Latin Americans, for example, become irritated by US citizens referring to their own country as America when in fact that term refers to two enormous continents. Another issue to consider is what dynamic exists between Latino/a and Latin American as terms identifying groups of people. We should add Caribbean to this discussion, which also complicates matters since Puerto Ricans are US citizens with histories tied to the Caribbean. Mexican Americans (or Chican/aos) live in a country that borders the other “half” of their designation. Both these cases introduce vexed questions about immigration and belonging. Queer itself is not a word that escapes controversy. It can be used as a provocation, to challenge hate language by neutralizing it. But does that work? How do we know when it does? And when do we know when we have succeeded and can drop its usage entirely? And does queer automatically mean gay? In its usage as an umbrella terms what happens to the specificity of same-sex desire? And finally, literature is itself a contested term as there is no critical consensus on what exactly designates written expression as literature as opposed to simply writing. Therefore I would argue that any attempt to be comprehensive about Queer Latinx literature can only be provisional. But any such attempt that is based on critical rigor and empathy should be welcomed.