bluuebunny/crossref_metadata_2025 huggingface dataset:
Data analytics case studies in the maintenance, repair and overhaul (MRO) industry
Authors: Pelt Maurice , Stamoulis Konstantinos , Apostolidis Asteris
Published: December 2019

Data analytics seems a promising approach to address the problem of unpredictability in MRO organizations. The Amsterdam University of Applied Sciences in cooperation with the aviation industry has initiated a two-year applied research project to explore the possibilities of data mining. More than 25 cases have been studied at eight different MRO enterprises. The CRISP-DM methodology is applied to have a structural guideline throughout the project. The data within MROs were explored and prepared. Individual case studies conducted with statistical and machine learning methods, were successfully to predict among others, the duration of planned maintenance tasks as well as the optimal maintenance intervals, the probability of the occurrence of findings during maintenance tasks.
Multifunctional load-bearing aerostructures with integrated space debris protection
Authors: Schubert Martin , Dafnis Anthanasios
Published: December 2019

In the project multiSat multifunctional composite structures for satellite application have been developed. Functions such as protection against space debris, radiation shielding and passive thermal control have been integrated into the load-bearing composite spacecraft structure by use of suitable materials and components. Sandwich panels have been studied as representative structural parts of a conventional satellite structure. Measures for increased space debris protection include the substitution of the conventional honeycomb core by 3D-printed aluminum cellular structures and the reinforcement of the sandwich panel by integration of high performance fabrics which effectively break up and catch impacting debris particles. This paper describes the development and design of multifunctional sandwich concepts with increased impact protection capability and presents the experimental results of hypervelocity impact testing with different types of CFRP sandwich panels.
A Reduced Order Model based on Large Eddy Simulation of Turbulent Combustion in the Hybrid Rocket Engine
Authors: Dănăilă Sterian , Isvoranu Dragos , Levențiu Constantin , Bogoi Alina
Published: December 2019

A combined method of large eddy simulations for non-premixed combustion in a turbulent boundary layer coupled with proper orthogonal decomposition of instantaneous velocity, pressure and temperature fields is developed in order to obtain a reduced order model. First, we investigate a channel turbulent reacting flow using Large Eddy Simulations (LES) technique. Polypropylene/O2 has been considered as fuel/oxidant pair. The turbulence-combustion interaction is based on a combination of finite rate/eddy dissipation model applied to a reduced chemical mechanism with four reactions. The LES numerical results are analyzed with respect to RANS simulations and with other reference data. The second part of the paper refers to the derivation of a Reduced Order Model (ROM) based on proper orthogonal decomposition (POD) technique for the unsteady flow field. In order to achieve that, the eigenmodes of the flow are computed from several snapshots of the instantaneous fields uniformly spaced and the most energetic ones are used to set up the Reduced Order Model. Constant regression rate of the fuel grain is considered. The flow and thermal fields obtained with ROMs are compared with the ones obtained from the full simulation and an analysis on the number of modes required to achieve the desired accuracy is presented.
Interprofessionelle Kommunikation zwischen therapeutisch Pflegenden
und anderen therapeutischen Berufsangehörigen (Physiotherapie,
Ergotherapie und Logopädie) in der neurologischen
Frührehabilitation
Authors: Franz Shiney , Muser Jürgen , Thielhorn Ulrike , Wallesch Claus-Werner , Behrens Johann
Published: December 2019

Ziel Durch einen Vergleich der Kommunikation in
pflegerisch-therapeutischen Teams von 5 neurologischen
Frührehabilitationskliniken eines gemeinnützigen Trägers
mit ähnlichem Profil sollen fördernde und hindernde Faktoren der
Kooperation identifiziert werden.

Methodik Vergleich der interprofessionellen Kommunikation in 5 funktional
äquivalenten Kliniken mit den Methoden der Dichten Beschreibung [1],
also Architekturplänen, passiv teilnehmender mitgehender
ganztägiger Beobachtungen für je eine Woche in 10
Frührehabilitationsstationen, dokumentiert in Memos
(Beobachtungsaufzeichnungen). Ergänzt wurden diese Beobachtungen durch
teilstrukturierte Leitfadeninterviews (n=39), in denen die Beobachtungen
besprochen wurden. Teilnehmende waren Berufsangehörige der Pflege,
Physiotherapie, Ergotherapie und Logopädie.

Ergebnisse Feste Teams, werktägliche auch informelle
Teambesprechungen, gemeinsame interprofessionelle Behandlungseinheiten,
stationsbezogene Fortbildungen und informelle Gespräche beeinflussen die
interprofessionelle Kommunikation positiv oder negativ (Fraktionsbildung,
Kooperationslücken). Dabei haben organisatorische und bauliche
Bedingungen einen vermutlich nicht zu unterschätzenden Einfluss auf die
Qualität der Kommunikation zwischen den Berufsgruppen.

Schlussfolgerung Kurze tägliche Teambesprechungen und die
Organisation von Fortbildungen auf Teamebene fördern die
interprofessionelle Kommunikation, eine auch baulich und organisatorisch
verstärkte Fraktionsbildung Pflege vs. Therapie beeinträchtigt
sie.
Classical three rotor problem: Periodic solutions, stability and chaos
Authors: Krishnaswami Govind S. , Senapati Himalaya
Published: December 2019

This paper concerns the classical dynamics of three coupled rotors: equal masses moving on a circle subject to attractive cosine interparticle potentials. This system arises as the classical limit of a model of coupled Josephson junctions. In appropriate units, the non-negative energy E of the relative motion is the only free parameter. We find families of periodic solutions: pendulum and isosceles solutions at all energies and choreographies up to moderate energies. The model displays order-chaos-order behavior: it is integrable at zero and infinitely high energies but displays a fairly sharp transition from regular to chaotic behavior as E is increased beyond Ec≈4 and a more gradual return to regularity. The transition to chaos is manifested in a dramatic rise of the fraction of the area of the Hill region of Poincaré surfaces occupied by chaotic sections and also in the spontaneous breaking of discrete symmetries of Poincaré sections present at lower energies. Interestingly, the above pendulum solutions alternate between being stable and unstable, with the transition energies cascading geometrically from either sides at E=4. The transition to chaos is also reflected in the curvature of the Jacobi-Maupertuis metric that ceases to be everywhere positive when E exceeds four. Examination of Poincaré sections also indicates global chaos in a band of energies (5.33≲E≲5.6) slightly above this transition.
Direct and indirect measurements of the electro-caloric effect in (Bi,Na)TiO3-SrTiO3 ceramics
Authors: Kim Dae Su , Kim Bit Chan , Han Seung Ho , Kang Hyung-Won , Kim Jeong Seog , Cheon Chae Il
Published: December 2019

The electrocaloric effect (ECE) in lead-free (Bi0.5Na0.5)TiO3-SrTiO3 (BNT-ST) ceramics was investigated by direct and indirect measurements. Polarization-electric field hysteresis loops of the BNT-ST ceramics changed from well-saturated shapes at room temperature to constricted shapes around the depolarization temperature due to an electric field-induced phase transition. A large adiabatic temperature change due to ECE (ΔTEC) was obtained around the phase transition temperature (TFR) by indirect measurements, which was confirmed by direct measurements. The 0.85BNT-0.15ST sample showed a large negative ΔTEC in the indirect measurements below TFR where the polarization increases, while the directly measured ΔTEC displayed positive values. It suggests that the indirect method using the Maxwell relation is not valid in the temperature range where the polarization increases with temperature. The X-ray diffraction structural refinements showed that the poled 0.85BNT-0.15ST sample has mixed phases of a rhombohedral R3C and a tetragonal P4bm in the temperature range where the polarization increases below TFR.
Performance of new crystal cathode pressure gauges for long-pulse operation in the Wendelstein 7-X stellarator
Authors: Wenzel Uwe , Schlisio Georg , Mulsow Matthias , Pedersen Thomas Sunn , Singer Martin , Marquardt Mirko , Pilopp Dirk , Rüter Nils
Published: December 2019

To improve the reliability of the ASDEX pressure gauges in the plasma vessel of the Wendelstein 7-X stellarator, nine of them were equipped with a LaB6 crystal electron emitter for the first time. These crystal cathode pressure gauges were operated during the last campaign in 2018 (operation phase 1.2b) with only 2 A heating current for over 40 h in a magnetic field of about 2.1 T without failure. Owing to this excellent performance, we have decided to equip all pressure gauges with crystal cathodes for the next campaign of Wendelstein 7-X (operation phase 2). We report on a pretest in a superconducting magnet, show a measurement of the neutral pressure in Wendelstein 7-X, and demonstrate the long-term stability of the crystal cathode pressure gauges.
A Bayesian nonparametric approach to the approximation of the global stable manifold
Authors: Hatjispyros Spyridon J. , Kaloudis Konstantinos
Published: December 2019

We propose a Bayesian nonparametric model based on Markov Chain Monte Carlo methods for unveiling the structure of the invariant global stable manifold from observed time-series data. The underlying unknown dynamical process could have been contaminated by additive noise. We introduce the Stable Manifold Geometric Stick Breaking Reconstruction model with which we reconstruct the unknown dynamic equations, while at the same time, we estimate the global structure of the perturbed stable manifold. Our method works for noninvertible maps without modifications. The stable manifold estimation procedure is demonstrated specifically in the case of polynomial maps. Simulations based on synthetic time-series are presented.
Deep reinforcement learning in World-Earth system models to discover sustainable management strategies
Authors: Strnad Felix M. , Barfuss Wolfram , Donges Jonathan F. , Heitzig Jobst
Published: December 2019

Increasingly complex nonlinear World-Earth system models are used for describing the dynamics of the biophysical Earth system and the socioeconomic and sociocultural World of human societies and their interactions. Identifying pathways toward a sustainable future in these models for informing policymakers and the wider public, e.g., pathways leading to robust mitigation of dangerous anthropogenic climate change, is a challenging and widely investigated task in the field of climate research and broader Earth system science. This problem is particularly difficult when constraints on avoiding transgressions of planetary boundaries and social foundations need to be taken into account. In this work, we propose to combine recently developed machine learning techniques, namely, deep reinforcement learning (DRL), with classical analysis of trajectories in the World-Earth system. Based on the concept of the agent-environment interface, we develop an agent that is generally able to act and learn in variable manageable environment models of the Earth system. We demonstrate the potential of our framework by applying DRL algorithms to two stylized World-Earth system models. Conceptually, we explore thereby the feasibility of finding novel global governance policies leading into a safe and just operating space constrained by certain planetary and socioeconomic boundaries. The artificially intelligent agent learns that the timing of a specific mix of taxing carbon emissions and subsidies on renewables is of crucial relevance for finding World-Earth system trajectories that are sustainable in the long term.
Hydrodynamic characteristics in a sheet flow upstream water flow of a circular cylinder
Authors: Yang P. P. , Zhang H. L. , Wang Y. Q. , Wang Y. J. , Li R.
Published: December 2019

Sheet flow featured with shallow depth on vegetated slopes plays a key role on the dynamics of soil and water loss, yet the hydrodynamic characteristics of sheet flow pasting a vegetation stem simplified by an emergent cylinder have not been revealed. Laboratory flume experiments were conducted to investigate potential effects of a vegetation stem on velocity components, flow vortexes, and shear stress from time-averaged and time-resolved perspectives. Flow fields on the upstream flow of the cylinder at the symmetry plane were captured by using a high precision Particle Image Velocimetry (PIV, 63 pixel/mm) system. Four flow conditions with flow depths from 0.4 to 0.57 cm and cylinder Reynolds number from 2440 to 3806 were selected to fully evaluate the sheet flow condition. Time-averaged hydrodynamic features were analyzed in terms of streamlines, streamwise velocity, wall-normal velocity, and vorticity. Time-resolved features of two velocity components were then analyzed. Joint probability density functions of the two velocity components exhibited asymmetrical bimodal, indicating two preferred flow states occurred frequently, namely, backflow event and downflow event. Subsequently, analyses by linear stochastic estimation showed that the backflow event was induced by a reverse upstream flow starting from the leading edge of the cylinder and penetrating primary horseshoe vortex, which was motivated by the intermediate-flow mode proposed in previous open channel flow. Meanwhile, the downflow event was induced by a portion of fluid that was unable to penetrate the primary horseshoe vortex and then vertically impinged the flume bed, which was motivated by the downflow mode proposed in this study. As the critical hydrodynamic parameter for local scouring, shear stress was finally sketched. It was suggested that soil control measures should be implemented around the vegetation stem with a radius of 0.1D (D is the cylinder diameter), where the maximum shear stress mostly occurs. The newly defined flow mode could provide deeper insights into the mechanisms of sheet flow and promote the practice of soil erosion control on vegetated hillslopes.
Analytic non-adiabatic derivative coupling terms for spin-orbit MRCI wavefunctions. II. Derivative coupling terms and coupling angle for KHeA2Π1/2⇔KHeB2Σ1/2
Authors: Belcher Lachlan T. , Lewis Charlton D. , Kedziora Gary S. , Weeks David E.
Published: December 2019

A method for calculating the analytic nonadiabatic derivative coupling terms (DCTs) for spin-orbit multi-reference configuration interaction wavefunctions is reviewed. The results of a sample calculation using a Stuttgart basis for KHe are presented. Additionally, the DCTs are compared with a simple calculation based on the Nikitin’s 3 × 3 description of the coupling between the Σ and Π surfaces, as well as a method based on Werner’s analysis of configuration interaction coefficients. The nonadiabatic coupling angle calculated by integrating the radial analytic DCTs using these different techniques matches extremely well. The resultant nonadiabatic energy surfaces for KHe are presented.
A microfluidic chip for single-cell 3D rotation enabling self-adaptive spatial localization
Authors: Huang Liang , Liang Fei , Feng Yongxiang
Published: December 2019

The three-dimensional (3D) rotation of a single cell is a fundamental manipulation process at the cellular level for physiological and pathological characterization. However, the motion of the cells is affected by factors such as fluid forces and gravitation forces; hence, it is difficult to maintain a stable spatial position of a single cell. Therefore, ensuring stable spatial positions for single-cell rotation is an essential problem that needs to be addressed. In this paper, we present a single cell microfluidic chip based on dielectrophoresis, for single-cell self-adaptive spatial localization and 3D rotation. Numerical simulation was performed to analyze the electric field under different signal configurations, effect of cell self-adaption, and levitation of individual cells. Based on the results, self-adaptive spatial localization and 3D rotation of single cells were successfully realized. By altering the electric signal profile, a greater level of control on cell rotation modes can be obtained. Furthermore, utilizing the out-of-plane rotation, we realize 3D morphology reconstruction of the single cell. The developed single-cell 3D rotation chip is directly applicable to cellular research processes including tomographic imaging and the acquisition of biophysical parameters.
Numerical simulation of film instability over low wettability surfaces through lubrication theory
Authors: Suzzi N. , Croce G.
Published: December 2019

A computational study of thin liquid films over a solid surface is reported. The lubrication equation is numerically solved using an in-house code, which implements the finite volume method. Small slope approximation is abandoned, and a more accurate model for capillary pressure estimation is presented, allowing us to correctly investigate higher contact angles, when compared to the maximum value allowed by small slope approximation. Disjoining pressure is used for modeling substrate wettability. The in-house solver is first validated: a 1D flowing film driven by gravity is simulated and the disjoining pressure model is verified for contact angles up to 60°; replicating literature experimental investigations, a uniform film covering an inclined plate is perturbed, inducing the generation of a large dry patch; rivulet buildup is simulated; and the numerical results are compared with fully 3D computations found in the literature and verified with analytical evidences. Then, a film flowing over an inclined plate bounded by lateral walls, which is a complex configuration commonly used for studying liquid behavior in structured packing, is investigated and relevant parameters are reported.
Two competing acceptors: Electronic structure of PNDITBT probed by time-resolved electron paramagnetic resonance spectroscopy
Authors: Matt Clemens , Stry Katja , Matsidik Rukiya , Sommer Michael , Biskup Till
Published: December 2019

Balanced charge transport is particularly important for transistors. Hence, ambipolar organic semiconductors with comparable transport capabilities for both positive and negative charges are highly sought-after. Here, we report detailed insights into the electronic structure of PNDITBT, which is an alternating copolymer of naphthalene diimide (NDI), thiophene, benzothiodiazole (B), and thiophene (T) units, as gained by time-resolved electron paramagnetic resonance (TREPR) spectroscopy combined with quantum-chemical calculations. The results are compared to those obtained for PNDIT2 and PCDTBT, which are derivatives without B and NDI acceptor units, respectively. These two polymers show dominant n- and p-channel behavior in organic field-effect transistors. The TBT moiety clearly dominates the electronic structure of PNDITBT, although less so than in PCDTBT. Furthermore, the triplet exciton most probably delocalizes along the backbone, exhibits a highly homogeneous environment, and planarizes the polymer backbone. Obtaining the zero-field splitting tensors of these triplet states by means of quantum-chemical calculations reveals the triplet energy sublevel associated with the molecular axis parallel to the backbone to be preferentially populated, while the one perpendicular to the aromatic plane is not populated at all, consistent with the spin-density distribution. PNDITBT consisting of two acceptors (NDI and B) has a complex electronic structure, as evident from the two charge-transfer bands in its absorption spectrum. TREPR spectroscopy provides a detailed insight on a molecular level not available by and complementing other methods.
Atto Thio 12 as a promising dye for photo-CIDNP
Authors: Sobol Alexander , Torres Felix , Aicher Anatol , Renn Alois , Riek Roland
Published: December 2019

Photo-CIDNP is one among different promising techniques to improve nuclear magnetic resonance (NMR) sensitivity. Being sensitive to particular amino acids makes it a promising candidate with respect to biological NMR. Our goal is to exploit new sensitizers and compare them to the present working horses flavin mononucleotide, bipyridyl, and the recently applied fluorescein. Among the investigated dyes, we found a new and very efficient one, Atto Thio 12, conveniently used in fluorescence microscopy with 2–3 fold enhanced polarization when compared to the established ones. We also show that diode lasers which are now available from near UV to IR can be efficiently used in photo-CIDNP. Results are obtained with the amino acids tyrosine and tryptophan.
Monolayer MoS2-based nonvolatile transistors with a titanium nitride in the gate
Authors: Huang Kailiang , Zhao Miao , Liu Xueyuan , Feng Chao , Sun Bing , Chang Hudong , Zeng Yuping , Liu Honggang
Published: December 2019

Low-power, nonvolatile transistors are demanded in the digital electronics development. In our work, molybdenum disulfide (MoS2) acts as the channel material integrated with TiN, which is used as a floating gate to build a floating gate transistor. Our transistor exhibits a large hysteresis of 4 V (Vd = 0.1 V), high on/off ratio of 105, and symmetry writing and erase voltage. The excellent device characteristics such as nondestructive data readout, low operation voltage, and wide memory window inherent in single-layer MoS2 show their great potential to be applied in nonvolatile memory cells.
Densest helical structures of hard spheres in narrow confinement: An analytic derivation
Authors: Chan Ho-Kei , Wang Yuqian , Han Hongyu
Published: December 2019

The emergence of helicity from the densest possible packings of equal-sized hard spheres in narrow cylindrical confinement can be understood in terms of a density maximization of repeating microconfigurations. At any cylinder-to-sphere diameter ratio D∈(1+3/2,2), a sphere can only be in contact with its nearest and second nearest neighbors along the vertical z-axis, and the densest possible helical structures are results of a minimized vertical separation between the first sphere and the third sphere for every consecutive triplet of spheres. By considering a density maximization of all microscopic triplets of mutually touching spheres, we show, by both analytical and numerical means, that the single helix at D∈(1+3/2,1+43/7) corresponds to a repetition of the same triplet configuration and that the double helix at D∈(1+43/7,2) corresponds to an alternation between two triplet configurations. The resulting analytic expressions for the positions of spheres in these helical structures could serve as a theoretical basis for developing novel chiral materials.
Origins of hydrogen that passivates bulk defects in silicon heterojunction solar cells
Authors: Sun Chang , Weigand William , Shi Jianwei , Yu Zhengshan , Basnet Rabin , Phang Sieu Pheng , Holman Zachary C. , Macdonald Daniel
Published: December 2019

Silicon heterojunction solar cell fabrication incorporates a significant amount of hydrogen into the silicon wafer bulk, and the amount of injected hydrogen is comparable to that introduced by silicon nitride films during a high-temperature firing step. In this work, the origins of the hydrogen injected during heterojunction cell processing have been identified. We demonstrate that the hydrogen plasma treatment that is routinely included to improve surface passivation considerably increases the hydrogen concentration in the wafers. We also show that the hydrogenated amorphous silicon i/p+ stack is more effective than the i/n+ stack for bulk hydrogen incorporation, and both are more effective than intrinsic films alone.
The milking frequency of primiparous cows in their early stage of lactation and its impact on milking performance
Authors: Sitkowska Beata , Piwczyński Dariusz , Kolenda Magdalena , Różańska-Zawieja Jolanta
Published: December 2019

An automatic milking system allows cows to present their full production capability by not limiting them to a specific time when the milking occurs or a fix number of milkings per day. The beginning of the first lactation is a key point in terms of subsequent milk production. The aim of the present study was to indicate the relationship between the milking frequency of primiparous cows during the first month of lactation and their subsequent milk performance. Material of the study consisted of 25 Polish herds of Holstein–Friesian dairy cattle. All cows were milked with the use of an automatic milking system. Animals were divided into five groups, depending on the milking frequency in the first month after calving (MFF). The collected data were statistically processed using the multifactorial ANOVA. The best milk and milking parameters characterised primiparous cows, for which the average number of milkings per day was at the level of 3–3.5 or above, this group did not have a preferred time for their milking. This group of cows milked more frequently during the first month of lactation (MFF5) and had the highest milk yield (MY) and milking duration. The highest culling percentage (57.77%) was noted within the group of primiparous cows with the lowest milking frequency during the first month of lactation (MFF1). MFF5 animals maintained better milk and milking parameters in all months of lactation than did those in the other groups. Older animals, that calved after the 28th month of life, and those that calved during warmer seasons, showed the tendency to have a lower milking frequency and poorer milk and milking parameters. The findings obtained in the present study are interesting in terms of their potential use, because they show that frequent milking during the first month after calving corresponds to a better overall MY during that lactation. Hopefully, by promoting frequent milkings at the beginning of lactation, farmer may increase the overall lactation MY.
Renewable electricity storage using electrolysis
Authors: Yan Zhifei , Hitt Jeremy L. , Turner John A. , Mallouk Thomas E.
Published: December 2019

Electrolysis converts electrical energy into chemical energy by storing electrons in the form of stable chemical bonds. The chemical energy can be used as a fuel or converted back to electricity when needed. Water electrolysis to hydrogen and oxygen is a well-established technology, whereas fundamental advances in CO
2
electrolysis are still needed to enable short-term and seasonal energy storage in the form of liquid fuels. This paper discusses the electrolytic reactions that can potentially enable renewable energy storage, including water, CO
2
and N
2
electrolysis. Recent progress and major obstacles associated with electrocatalysis and mass transfer management at a system level are reviewed. We conclude that knowledge and strategies are transferable between these different electrochemical technologies, although there are also unique complications that arise from the specifics of the reactions involved.
Provincial and sector-level material footprints in China
Authors: Jiang Meng , Behrens Paul , Wang Tao , Tang Zhipeng , Yu Yadong , Chen Dingjiang , Liu Lin , Ren Zijian , Zhou Wenji , Zhu Shengjun , He Canfei , Tukker Arnold , Zhu Bing
Published: December 2019

Significance

China has undergone unprecedented increases in material development and by 2010 drove 30% of the global material footprint (MF). Understanding China’s MF distribution and development is critical for resource efficiency and circular economy ambitions globally. We combine a provincial input–output table (IOT), province-specific import–export statistics, a global IOT, and detailed extraction data to assess sector-specific and province-specific MFs in China. Capital investment—crucial to China’s development—is up to 4 times more resource-intensive than consumption and comprises 49 to 86% of provincial MF. We find large differences in MF per capita across provinces, even among those with similar development characteristics. Findings indicate the need for improved understanding of material developments in other emerging countries in the 21st century.
Evoked potentials as a biomarker of remyelination
Authors: Heidari Moones , Radcliff Abigail B. , McLellan Gillian J. , Ver Hoeve James N. , Chan Kore , Kiland Julie A. , Keuler Nicholas S. , August Benjamin K. , Sebo Dylan , Field Aaron S. , Duncan Ian D.
Published: December 2019

Significance

Remyelination is a critical therapeutic target in MS that will restore function and protect demyelinated axons. Clinical trials of putative remyelination-promoting drugs depend on valid, robust, and noninvasive outcome measures. To date, MRI has failed to provide outcome metrics sufficiently sensitive and specific to remyelination. Optic neuritis is a common symptom of MS and visual evoked potentials (VEPs) have been proposed to identify demyelination during acute disease and subsequent remyelination, but this is unproven. Here, we use an animal model with severe optic nerve demyelination and subsequent remyelination to show that the VEP latency truly measures these myelin sheath changes. Hence, the VEP can be used as an outcome measure in future MS trials in which remyelination is the goal.
A bacterial surface layer protein exploits multistep crystallization for rapid self-assembly
Authors: Herrmann Jonathan , Li Po-Nan , Jabbarpour Fatemeh , Chan Anson C. K. , Rajkovic Ivan , Matsui Tsutomu , Shapiro Lucy , Smit John , Weiss Thomas M. , Murphy Michael E. P. , Wakatsuki Soichi
Published: December 2019

Surface layers (S-layers) are crystalline protein coats surrounding microbial cells. S-layer proteins (SLPs) regulate their extracellular self-assembly by crystallizing when exposed to an environmental trigger. However, molecular mechanisms governing rapid protein crystallization in vivo or in vitro are largely unknown. Here, we demonstrate that the
Caulobacter crescentus
SLP readily crystallizes into sheets in vitro via a calcium-triggered multistep assembly pathway. This pathway involves 2 domains serving distinct functions in assembly. The C-terminal crystallization domain forms the physiological 2-dimensional (2D) crystal lattice, but full-length protein crystallizes multiple orders of magnitude faster due to the N-terminal nucleation domain. Observing crystallization using a time course of electron cryo-microscopy (Cryo-EM) imaging reveals a crystalline intermediate wherein N-terminal nucleation domains exhibit motional dynamics with respect to rigid lattice-forming crystallization domains. Dynamic flexibility between the 2 domains rationalizes efficient S-layer crystal nucleation on the curved cellular surface. Rate enhancement of protein crystallization by a discrete nucleation domain may enable engineering of kinetically controllable self-assembling 2D macromolecular nanomaterials.
FBXW7-mediated stability regulation of signal transducer and activator of transcription 2 in melanoma formation
Authors: Lee Cheol-Jung , An Hyun-Jung , Kim Seung-Min , Yoo Sun-Mi , Park Juhee , Lee Ga-Eun , Kim Woo-Young , Kim Dae Joon , Kang Han Chang , Lee Joo Young , Lee Hye Suk , Cho Sung-Jun , Cho Yong-Yeon
Published: December 2019

Significance

The physiological relevance of STAT2 (a member of STAT family) in melanoma formation is clearly shown using a human skin tissue array. Moreover, FBXW7-mediated STAT2 protein stability regulation via ubiquitination is shown to play an essential role in melanoma cell proliferation in monolayer and anchorage-independent 3D culture systems. The molecular mechanisms that regulate STAT2 protein stability by FBXW7 include the interaction between CCD and DBD domains of STAT2 and the WD40 domain of FBXW7. STAT2 phosphorylation at the putative degron motifs that contain Ser381, Thr385, and Ser393 might be mediated by GSK3β. These serve as critical amino acids that form hydrogen bonds with the WD40 domain of FBXW7. Thus, the FBXW7–STAT2 signaling axis is an important target for melanoma treatment.
The role of translationally controlled tumor protein in proliferation of
Drosophila
intestinal stem cells
Authors: Kwon Young V. , Zhao Bingqing , Xu Chiwei , Lee Jiae , Chen Chiao-Lin , Vinayagam Arunachalam , Edgar Bruce A. , Perrimon Norbert
Published: December 2019

Significance

Translationally controlled tumor protein (TCTP) is a conserved protein that regulates tissue growth in various multicellular organisms. Although precise control of growth is an integral part of the tissue repair process, it has remained unclear whether and how TCTP functions during tissue regeneration. By employing
Drosophila
genetics, we demonstrate that TCTP plays a crucial role in regeneration of damaged intestinal epithelium in part by regulating protein translation. Furthermore, we elucidate an unexpected crosstalk between TCTP and 2 key growth regulatory signaling pathways in animals. Altogether, our study provides insights into the mechanisms by which TCTP precisely controls tissue growth during animal development and regeneration.
Mangroves protect coastal economic activity from hurricanes
Authors: del Valle Alejandro , Eriksson Mathilda , Ishizawa Oscar A. , Miranda Juan Jose
Published: December 2019

This paper evaluates whether mangroves can mitigate the impact of hurricanes on economic activity. The paper assembles a regionwide panel dataset that measures local economic activity using nightlights, potential hurricane damages using a detailed wind field model, and mangrove protection by mapping the width of mangrove forests on the path to the coast. The results show that hurricanes have negative short-run effects on economic activity, with losses likely concentrated in coastal lowlands that are exposed to both wind and storm surge hazards. In these coastal lowlands, the estimates show that nightlights decrease by up to 24% in areas that are unprotected by mangroves. By comparison, the impact of the hurricanes observed in the sample is fully mitigated in areas protected by mangrove belts of 1 km or more.
Deep learning predicts path-dependent plasticity
Authors: Mozaffar M. , Bostanabad R. , Chen W. , Ehmann K. , Cao J. , Bessa M. A.
Published: December 2019

Plasticity theory aims at describing the yield loci and work hardening of a material under general deformation states. Most of its complexity arises from the nontrivial dependence of the yield loci on the complete strain history of a material and its microstructure. This motivated 3 ingenious simplifications that underpinned a century of developments in this field: 1) yield criteria describing yield loci location; 2) associative or nonassociative flow rules defining the direction of plastic flow; and 3) effective stress–strain laws consistent with the plastic work equivalence principle. However, 2 key complications arise from these simplifications. First, finding equations that describe these 3 assumptions for materials with complex microstructures is not trivial. Second, yield surface evolution needs to be traced iteratively, i.e., through a return mapping algorithm. Here, we show that these assumptions are not needed in the context of sequence learning when using recurrent neural networks, diverting the above-mentioned complications. This work offers an alternative to currently established plasticity formulations by providing the foundations for finding history- and microstructure-dependent constitutive models through deep learning.
A social–ecological analysis of the global agrifood system
Authors: Oteros-Rozas Elisa , Ruiz-Almeida Adriana , Aguado Mateo , González José A. , Rivera-Ferre Marta G.
Published: December 2019

Significance

The failure to end hunger and the environmental deterioration underpinning food systems have prompted a paradigm shift around food security. We propose a social–ecological approach and carry out a quantitative analysis of 43 indicators of food sovereignty and 28 indicators of the sociodemographic, social wellbeing, and environmental sustainability situation in 150 countries. The results highlight the existence of an agrifood debt among countries (i.e., disequilibria in the natural resources consumed, the environmental impacts, and the social wellbeing in regions that play different roles within the globalized agrifood system). Three spotlights underpin this debt: 1) interregional contrasts in food security, 2) a concern about the role of agrifood trade, and 3) a mismatch between regional biocapacity and food security.
Disclinations and disconnections in minerals and metals
Authors: Hirth John P. , Hirth Greg , Wang Jian
Published: December 2019

Significance

A different type of line defect, coherency disclinations that appear whenever a coherent interface terminates, has several types of applications, as do disconnections with disclination content. We anticipate many future applications of the model to twinning, phase transformations, and grain boundary motion, particularly in minerals where slip is usually limited.
Sources of off-target expression from recombinase-dependent AAV vectors and mitigation with cross-over insensitive ATG-out vectors
Authors: Fischer Kyle B. , Collins Hannah K. , Callaway Edward M.
Published: December 2019

Significance

The widespread use of recombinase-dependent adeno-associated virus (AAV) for targeting transgene expression to specific neural populations has made it a fundamental tool for neural manipulation and circuit dissection. Despite this, the well-known but oft-ignored issue of unwanted recombinase-independent “leak” expression from common recombinase-dependent DIO and FLEX AAV designs impedes certain applications and confounds data. Herein we discover that the leak expression from these constructs is due to both low-level expression of the inverted transgene and homology-dependent recombination in bacteria during plasmid production. Using this knowledge, we create a Cre-dependent AAV design that greatly decreases leak expression. This development will improve cell-type-specific transgene targeting for a wide spectrum of tools dependent on precise cell-type-specific targeting.
Language, religion, and communication
Authors: Al Shlowiy Ahmed Saad
Published: December 2019

The Arabic language is associated with Islam and is the language of the Holy Qur’an, which Muslims believe to be
God’s words. Due to religious, educational, socio-cultural, and geographic factors, Qur’anic Arabic is revered by many Muslims in
the Asian Pacific countries, who use the language to perform religious rituals. Those Muslims use the language as an Islamic
lingua franca to communicate with each other. This paper discusses the historical relationship between Islam and Arabic, how this
relationship strengthens both of them, and how they both spread across the world, especially to the Asian Pacific countries that
have the majority of the world’s non-Arab Muslims. It also sheds light upon the ways in which Islam preserves the Arabic language
and converts it into a universal language that is used in all of these countries. This leads the discussion of how learning Arabic
in Asian Pacific communities strengthens communication not only among Muslims but also within each Muslim to conduct his/her
religious deeds, prayers, and behaviors. The paper also attempts to explore the possibility of learning Arabic as a foreign
language by some Non-Muslims in those communities.
Activated PI3Kδ breaches multiple B cell tolerance checkpoints and causes autoantibody production
Authors: Lau Anthony , Avery Danielle T. , Jackson Katherine , Lenthall Helen , Volpi Stefano , Brigden Henry , Russell Amanda J. , Bier Julia , Reed Joanne H. , Smart Joanne M. , Cole Theresa , Choo Sharon , Gray Paul E. , Berglund Lucinda J. , Hsu Peter , Wong Melanie , O’Sullivan Michael , Boztug Kaan , Meyts Isabelle , Uzel Gulbu , Notarangelo Luigi D. , Brink Robert , Goodnow Christopher C. , Tangye Stuart G. , Deenick Elissa K.
Published: December 2019

Antibody-mediated autoimmune diseases are a major health burden. However, our understanding of how self-reactive B cells escape self-tolerance checkpoints to secrete pathogenic autoantibodies remains incomplete. Here, we demonstrate that patients with monogenic immune dysregulation caused by gain-of-function mutations in PIK3CD, encoding the p110δ catalytic subunit of phosphoinositide 3-kinase (PI3K), have highly penetrant secretion of autoreactive IgM antibodies. In mice with the corresponding heterozygous Pik3cd activating mutation, self-reactive B cells exhibit a cell-autonomous subversion of their response to self-antigen: instead of becoming tolerized and repressed from secreting autoantibody, Pik3cd gain-of-function B cells are activated by self-antigen to form plasmablasts that secrete high titers of germline-encoded IgM autoantibody and hypermutating germinal center B cells. However, within the germinal center, peripheral tolerance was still enforced, and there was selection against B cells with high affinity for self-antigen. These data show that the strength of PI3K signaling is a key regulator of pregerminal center B cell self-tolerance and thus represents a druggable pathway to treat antibody-mediated autoimmunity.
Ligand-free upconversion nanoparticles for cell labeling and their effects on stem cell differentiation
Authors: Ren Na , Liang Na , Yu Xin , Wang Aizhu , Xie Juan , Sun Chunhui
Published: December 2019

Recently, the wide application of upconversion nanoparticles (UCNPs) in the field of bioimaging has raised the requirement of biocompatibility. Current cytocompatibility studies on UCNPs mainly focus on cancer cells; however, their potential effects on normal cells are rarely addressed. Herein, the cellular effects of a trace amount of ligand-free NaYF4:Yb/Er nanocrystals on the differentiation of rat bone mesenchymal stem cells (rBMSCs) were investigated. First, due to their excellent upconversion fluorescent properties, the cellular uptake of ligand-free NaYF4:Yb/Er nanocrystals was confirmed by confocal laser scanning microscopy, and a homogeneous cytoplasmic distribution was imaged. Second, the viability of the rBMSCs cultured with a series of concentrations of nanoparticles (0, 30, 300, and 3000 ng ml−1) was evaluated, and a dose threshold was determined. Third, the effects of ligand-free NaYF4:Yb/Er nanocrystals on the osteogenesis of the rBMSCs were intensively characterized. The alkaline phosphatase activity assay, quantitative real time polymerase chain reaction for related osteogenic genes, and immunofluorescence staining of specific biomarkers and mineral deposits demonstrated that the ligand-free NaYF4:Yb/Er nanocrystals at a proper concentration can enhance osteogenic differentiation. Finally, intracytoplasmic lipid detection showed that the adipogenic differentiation of rBMSCs might be inhibited in the presence of ligand-free NaYF4:Yb/Er nanocrystals. Meanwhile, these results showed that the effects of ligand-free NaYF4:Yb/Er nanocrystals on rBMSCs were concentration-dependent and reciprocal between osteogenic and adipogenic differentiation. This work provides new insights into the exploring the biocompatibility of UCNPs and will benefit the research community engaged in nanotechnology and biomedicine.
Critical phenomenon of the layered chiral helimagnetic YbNi3Al9
Authors: Wang Yamei , Liu Wei , Zhao Jun , Fan Jiyu , Pi Li , Zhang Lei , Zhang Yuheng
Published: December 2019

Two-dimensional layered YbNi3Al9 exhibits a chiral helimagnetic ground state, which is a candidate for the field-modulated chiral magnetic soliton. In this work, the magnetism and critical phenomenon of YbNi3Al9 are investigated. As H ⊥ c, a magnetic step with loop can be observed in the field-dependent magnetization, which may be corresponding to the possible chiral magnetic soliton phase transition. Based on the analysis of isothermal magnetization around T

C
, the critical exponents are obtained as β = 0.1370(2), γ = 1.7955(4), and δ = 14.1043(7), which fulfill the Widom scaling relation and Rushbrooke’s law. Moreover, the obtained critical exponents are testified by the modified Arrott plot and scaling hypothesis. The critical exponents of YbNi3Al9 are close to the theoretically prediction of 2D-Ising model with the spatial-dimensionality n = 2 and spin-dimensionality d = 1, indicating one-dimensional magnetic coupling in the two-dimensional framework. Based on universality scaling, we construct the detailed H–T phase diagram around the phase transition with H ⊥ c, which reveals that the field-induced magnetic transition for H ⊥ c is of the first-order type.
Reduction of non-linearity effects for a class of hyper-spectral radiometers
Authors: Talone Marco , Zibordi Giuseppe , Białek Agnieska
Published: December 2019

We determined the non-linearity coefficients of RAMSES hyper-spectral radiometers by relying on measurements performed at two distances from a reference source, i.e. d

C
and

, leading to equivalent digital counts in a large portion of the spectrum when doubling the integration time. Results from the proposed two-distance method are comparable to those obtained through a comprehensive characterization based on multi-distance measurements. Specifically, the differences between the non-linearity coefficients obtained from the two characterization approaches exhibit values lower than their respective standard deviations over most of the spectral range, except for the blue spectral region due to operational limits of the multi-distance method. This finding supports the use of the simpler two-distance method for the characterization of the non-linearity coefficients of individual instruments, opposite to the application of the non-linearity coefficients recently recommended for the entire class hyperspectral radiometers matter of this investigation.
Combination of columnar transposition cipher caesar cipher and lempel ziv welch algorithm in image security and compression
Authors: Rachmawati Dian , Melvani Hardi Sri , Partogi Pasaribu Raju
Published: December 2019

Exchange of information through the medium of the internet allows information can be accessed by unauthorized parties. Techniques for securing information that is commonly used is Cryptography. This research will use a combination of two classic algorithms which are Columnar Transposition Cipher and a Caesar Cipher with a Linear Congruential Generator modification. Information in the form of images often has some of the same pixel value components. For saving the memory then the writers use the technique of compression with Lempel Ziv Welch algorithm, which is a dictionary-based compression algorithm. Stages of the process used in this study are that the pictures will be encrypted using the algorithm of Columnar Transposition Cipher, next step the file that has been encrypted will be encrypted with the Caesar Cipher algorithm using a combination of and Linear Congruential generators are modified. Then the image file that has been encrypted will be compressed using the second algorithm Lempel Ziv Welch. For the implementation of programming language C # systems used. The results of this study showed that the combination of Columnar Transposition Cipher and a Caesar Cipher with a Linear Congruential Generators could keep the confidentiality, integrity, and security of data. Lempel Ziv Welch algorithm produces the value of the average compression ratio (RC) 67.05%, in Compression Ratio (CR) aspect the value is 1.49, and in Space Saving (SS) parameter, the percentage is 32.93%.
Design of Expert System for Diagnosis Damage Computer Hardware
Authors: Devita Retno , Rianti Eva , Rahmawati Sri
Published: December 2019

Expert systems are developed in line with the existence of information technology. The development of expert systems aims as a tool to provide solutions in lives. Expert systems can also help in making better solutions. With the rapid technological advancement at this time, raising an idea or idea to try to implement one of expert system application program into activity of service quality of computer technician by using method of Cased Based Reasing (CBR). This expert system application built can help technicians find solutions quickly and save time. Users and technicians simply enter the symptoms of damage that occurs in computer hardware. Through the built application helps in providing solutions to damage to computer hardware so as to facilitate the user or technician to get the solution quickly.