bluuebunny/crossref_metadata_2025 huggingface dataset:
The Relationship Between Rotary Chair and Video Head Impulse Testing in Children and Young Adults With Cochlear Implants
Authors: Janky Kristen L. , Patterson Jessie
Published: November 2020

Purpose

Conflicts among video head impulse testing (vHIT) and rotary chair have occurred; therefore, the purpose of this study was to determine the relationship between rotary chair and vHIT outcome parameters to understand when these two tests disagree and determine if one or both test outcomes are needed in children.

Method

Data from 141 child and young adult subjects (73 males, 68 females,
M
age
= 15 years, range: 6–35) were retrospectively reviewed. Of those, 56 had a cochlear implant and 85 were normal controls. All subjects completed rotary chair and vHIT, which were categorized as (a) normal vestibular function, (b) unilateral vestibular loss, or (c) bilateral vestibular loss. vHIT tracings were analyzed to determine if gain and corrective saccade velocity, frequency, or latency were helpful parameters for determining vestibular loss.

Results

Of the 141 subjects, the misclassification rate was 13/141 (9%). All normal control subjects were classified as having normal rotary chair and normal vHIT. In subjects with a cochlear implant (
n
= 56), the misclassification rate was 13/56 (23%). There were four misclassification patterns. Using rotary chair as the gold standard, receiver operating characteristic analysis revealed optimal cut-points for vHIT gain (< 0.84), corrective saccade frequency (≥ 50%), amplitude (≥ 75°/s), and latency (≤ 320 ms). Using these vHIT cut-points improved the agreement between rotary chair and vHIT, resulting in an overall misclassification rate of 10/141 (7%) and 9/56 (16%) in subjects with a cochlear implant.

Conclusions

When testing children, caloric testing is often not an option due to tolerability or time. However, discordant results occur between rotary chair and vHIT. These data suggest vHIT is a sufficient first-tier assessment. If abnormal, rotary chair is not necessary. If normal, rotary chair can be helpful for uncovering other indicators of vestibular loss. When interpreting vHIT, including gain and all corrective saccade outcomes may improve sensitivity.
The Effects of Shared e-Book Reading With Dynamic Text and Speech Output on the Single-Word Reading Skills of Young Children With Developmental Disabilities
Authors: Boyle Susannah , McNaughton David , Light Janice , Babb Salena , Chapin Shelley E.
Published: November 2020

Purpose

This study investigated the use of a new software feature, namely, dynamic text with speech output, on the acquisition of single-word reading skills by six children with developmental disabilities during shared e-book reading experiences with six typically developing peers.

Method

A single-subject, multiple-probe design across participants was used to evaluate the effects of the software intervention. Six children with developmental delays were the primary focus for intervention, while six children with typical development participated as peer partners in intervention activities. e-Books were created with the new software feature, in which a child selects a picture from the e-book and the written word is presented dynamically and then spoken out. These e-books were then used in shared reading activities with dyads including a child with a disability and a peer with typical development. Participants engaged in the shared reading activity for an average of 13 sessions over a 6-week time period, an average of 65 min of intervention for each dyad.

Results

Participants with disabilities acquired an average of 73% of the words to which they were exposed, a gain of 4.3 words above the baseline average of 1.7 correct responses. The average effect size (Tau-U) was .94, evidence of a very large effect.

Conclusion

The results provide evidence that the use of e-books with the dynamic text and speech output feature during inclusive shared reading activities can be an effective and socially valid method to develop the single-word reading skills of young children with developmental disabilities.
Improved deterministic and stochastic models for simulating partial discharges in non‐conducting trees inside solid dielectrics
Authors: Rodríguez‐Serna Johnatan M. , Albarracín‐Sánchez Ricardo
Published: November 2020

Electrical trees are defects originated and driven by partial discharges (PD) activity and this is the reason why their modelling and simulation are fundamental for the ageing mechanisms comprehension and diagnosis analyses of insulation systems compound by solid dielectrics. This study presents a brief review of the different models implemented to simulate PD in electrical trees inside solid dielectrics. In addition, an improved deterministic model as well as a stochastic model are presented, which allow predicting adequately the PD pulses distribution, in magnitudes and phase, for non‐conducting electrical trees of different shape and length. Two case studies were simulated and their results exhibit good agreement when compared with measurements presented in the literature. It is concluded that the main parameters that state the PD behaviour in trees are the inception and extinction voltage magnitudes, including their probability distributions, and the tree geometry. The models can be used for prognosis analysis based on on‐line measurements.
Multiparametric quality by design-fuzzy model applied in the development of a biomedical measuring system
Authors: Tasé Velázquez Daniel René , Costa Monteiro Elisabeth , Ramos Louzada Daniel , Barbosa Carlos Roberto Hall
Published: November 2020

This work presents the adaptation of the Quality by Design (QbD) approach for application in the quality assurance of a biomedical measuring system under development. First attempts in applying QbD to biomedical technologies indicated a significantly higher number of parameters than its traditional application in the pharmaceutical industry. These preliminary studies did not fulfill the QbD stage of Design Space (DS) configuration for biomedical devices, an essential step to identifying the proper operating ranges of parameters and guaranteeing quality features. Therefore, it persisted the challenge of configuring DS for health devices, overcoming dependences in the interaction of multiple process parameters and critical attributes. The present work develops a hybrid QbD-Fuzzy approach for multiparametric DS configuration. The proposed method was applied in the development phase of a low-cost and high-sensitive magnetic measuring system for locating metallic foreign bodies in patients, employing sensors based on the Giant Magnetoimpedance effect. The results provided the acceptable operating ranges of the multiple process parameters to ensure the biomedical equipment's suitability. The proposed strategy contributes to the QbD implementation in biomedical technologies and, therefore, promotes the reliability of diagnostic and therapeutic results in the clinical environment.
On the effect of long service exposure: changes in microstructure and mechanical properties of Ni-based superalloy
Authors: Keyvanlou Hassan , Soleimani Gilakjani Reza , Nezakat Majid
Published: November 2020

In the present study, the microstructure and the mechanical properties of GTD-111 nickel-based superalloy were investigated. The alloy was in service as the GE-MS9001 gas turbine 1st stage rotating blade for 105,000 hours at a temperature between 950 to 1000 °C. Two sets of samples were extracted from the airfoil and the root of the blade. Then, they were compared for the microstructural and the mechanical properties changes after the high temperature service. Stress-rupture and Charpy V-notch (CVN) tests were conducted on the samples at 871 °C and two temperatures of 25 and 900 °C, respectively. The microstructure and the fracture surface of the samples were analyzed using a scanning electron microscope (SEM). The results showed degradation in the microstructure and the mechanical properties of the airfoil compared to those of the root due to the long-term service at elevated temperatures. The loss in mechanical properties was due to the coarsening ofγ’ precipitates and the formation of brittle phases in the grain boundaries.
Stellungnahme
Authors: Heudorf Ursel ,   für die Autoren
Published: November 2020

Die Autoren bedanken sich bei Herrn PD. Dr. Weigl für seinen Leserbrief und
die Klarstellungen zu dem Vorgehen in Plön. Wir werden wie er die weitere
Entwicklung beobachten, gerade auch im Hinblick auf die Corona-Pandemie, die
für die Gesundheitsämter eine enorme Herausforderung darstellt und
von ihnen eine hohe Flexibilität erfordert, um die präventiven
Aufgaben des öffentlichen Gesundheitsdienstes – und dazu
zählt die Schuleingangsuntersuchung – zielgerichtet weiter
wahrzunehmen.
Characterization of a carbon fiber composite material for space applications under high strains and stresses: Modeling and validation by experiments
Authors: Jaulin V. , Chevalier J.-M. , Arrigoni M. , Lescoute E.
Published: November 2020

The authors present the characterization of the behavior of a Carbon Fiber Reinforced Polymer (CFRP) under dynamic loading. The study deals with thin shields representative of the shields employed for satellite protection. The process was divided into two steps. First, experiments over a wide scale of strain rates were performed, including planar plate impacts, electron beam shots, and laser-induced shocks. The loads generated by these experiments can be unidirectional or two-dimensional with durations from a tenth of nanoseconds up to several microseconds. Rear surface velocities were recorded by Doppler Laser Interferometry, and damaged target was recovered when possible. Analysis of these results provides data about equation of state, elasto-plasticity behavior, and the damage process. In a second part, those data were used to develop an isotropic numerical model for the CFRP composite. This model is assessed in simulations with the hydrocode HESIONE (CEA) for all the previous experiments. Although slight differences were highlighted for laser-induced shocks, the model provides relevant results for simulating dynamic behavior of the CFRP composite.
Irradiation-enhanced torsional buckling capacity of carbon nanotube bundles
Authors: Wallace Joseph , Chen Di , Shao Lin
Published: November 2020

Molecular dynamics simulations are used to understand the torsional buckling of pristine and irradiated carbon nanotube (CNT) bundles. Irradiation-induced inter-tube defects are shown to significantly increase the critical buckling torque and critical buckling angle, while slightly increasing the torsional stiffness. In contrast, intra-tube defects are found to degrade the torsional properties. Such competing interactions cause irradiation enhancement to occur in large bundles where significant inter-tube bonding can occur. However, the irradiation enhancement effect becomes weak for very large bundles in which enhanced inter-tube interactions already exist in unirradiated bundles. In pristine CNT bundles of all sizes under torsional loading, CNTs can slip via the weakly interacting van der Waals force, whereas in the irradiated bundles, the inter-tube defects prevent slipping. The study further shows that the formation of one-dimensional carbon chain defects contributes to enhanced friction under slipping.
Effect of polarization fatigue on the electrocaloric effect of relaxor Pb0.92La0.08Zr0.65Ti0.35O3 thin film
Authors: Guo Mengyao , Sun Buwei , Wu Ming , Sun Haonan , Zhang Le , Liu Qida , Wang Danyang , Lou Xiaojie
Published: November 2020

The electrocaloric effect represents an adiabatic temperature change or isothermal entropy change upon the application or removal of an external electric field. However, the effect of the repetitive bipolar/unipolar electric field on the electrocaloric effect in ferroelectrics is not well understood. In this work, the electrocaloric effect after both bipolar and unipolar electrical cycling in Pb0.92La0.08Zr0.65Ti0.35O3 relaxor thin films has been indirectly evaluated using the Maxwell relationship. It was found that at room temperature, the electrocaloric temperature change ΔT under higher electric fields decreases gradually from a positive value to a negative one with the increase in the bipolar/unipolar fatigue cycle number. Intriguingly, around the Curie temperature, the positive ΔT of the film after bipolar/unipolar cycling was found to decrease under low or intermediate electric fields, while it remains almost unchanged under high electric fields. This behavior is attributed to the pinning effect of defects caused by phase decomposition during both bipolar and unipolar fatigue. Note that the increase in polarization by temperature induced domain depinning close to room temperature after the fatigue process is manifested by using the Maxwell relation indirectly. Our work further reveals the origin of both the electrocaloric effect and ferroelectric electrical fatigue and is important for the applications of practical electrocaloric refrigerators.
Improvement in solar cell efficiency based on the MAPbI3 films extracted by a mixed anti-solvent
Authors: Jiang Junjie , Yang Xingming , Huang Yuyang , Li Mengmeng , Tao Qianyu , Fei Mingjun , Cai H. L. , Zhang F. M. , Wu X. S.
Published: November 2020

In this report, we discuss the 22% efficiency improvement of solar cells based on the MAPbI3 perovskite film extracted with a mixed anti-solvent. The film quality of MAPbI3 extracted from the mixed anti-solvent of ether and isopropanol is improved greatly. The average grain size of the film may be enlarged twice. We argue that some solvents residing in the precursor may effectively promote the crystallization process of MAPbI3 to form large grains. We believe that this study may open a method to fabricate high-quality MAPbI3 perovskite films for highly efficient solar cells.
Probing edge condition of nanoscale CoFeB/MgO magnetic tunnel junctions by spin-wave resonance
Authors: Shinozaki M. , Dohi T. , Igarashi J. , Llandro J. , Fukami S. , Sato H. , Ohno H.
Published: November 2020

We investigate spin-wave resonance in nanoscale CoFeB/MgO magnetic tunnel junctions (MTJs) with a perpendicular easy axis and various free-layer sizes. Two types of MTJs are fabricated by different process conditions, and the spin-wave resonance is measured with homodyne-detected ferromagnetic resonance. We focus on the distance between resonance frequencies of the uniform and spin-wave modes as a function of the free-layer size in order to examine the effect of the edge state of MTJs. A marked difference is observed between the two types of MTJs, and the result is consistently reproduced by a model assuming free- or fixed-edge boundary conditions with or without reduced magnetic properties near the pattern edge for each MTJ. The obtained results indicate that the edge state of nanoscale MTJs is crucially affected by the process condition, and spin-wave resonance can serve as a sensitive probe for the edge condition.
Modeling of emittance growth due to Coulomb collisions in plasma-based accelerators
Authors: Zhao Y. , Lehe R. , Myers A. , Thévenet M. , Huebl A. , Schroeder C. B. , Vay J.-L.
Published: November 2020

Coulomb collisions with background plasma are one source of emittance degradation in plasma accelerators. This paper shows that the emittance growth due to Coulomb collisions can be correctly captured in particle-in-cell simulations, with a proper Monte Carlo binary collision module. The theory of the emittance growth due to Coulomb collisions is extended from a monoenergetic matched beam to a mismatched beam with energy spread and is compared with simulation results.
Calculating multipactor susceptibility chart using a semi-analytic approach with improved accuracy
Authors: Mirmozafari M. , Behdad N. , Booske J. H.
Published: November 2020

We propose a semi-analytic approach to investigate the multipactor in parallel plate structures with improved accuracy. The effects of emission velocity and transit time of electrons are studied and their corresponding susceptibility charts are calculated. As a result, the proposed model covers more dynamics of multipactor. In calculating the susceptibility chart, we propose a decision-making process taking into account impact velocity, required voltage, and trajectory of electrons. Therefore, we obtain a more accurate susceptibility chart that excludes non-physical scenarios. Our investigation reveals a different mechanism of multipactor, where the transit time of an electron across the gap can be either shorter or longer than the conventional half-cycle of the RF signal. The extent of this deviation depends on the maximum emission velocity of the secondaries. With this deviation, we demonstrate that the multipactor evolves over broader practical situations occurring not necessarily within a half-cycle of the RF signal. Finally, we study the higher-order multipactor resonances and also calculate their susceptibility charts. We demonstrate an overlap between the susceptibility charts of different orders depending on the emission velocity of primary electrons. The discussions herein provide an insight into the underlying dynamics of the multipactor, which can be used for practical multipactor suppression methods.
Inertial migration of oblate spheroids in a plane channel
Authors: Nizkaya Tatiana V. , Gekova Anna S. , Harting Jens , Asmolov Evgeny S. , Vinogradova Olga I.
Published: November 2020

We discuss an inertial migration of oblate spheroids in a plane channel, where the steady laminar flow is generated by a pressure gradient. Our lattice Boltzmann simulations show that spheroids orient in the flow, so that their minor axis coincides with the vorticity direction (a log-rolling motion). Interestingly, for spheroids of moderate aspect ratios, the equilibrium positions relative to the channel walls depend only on their equatorial radius a. By analyzing the inertial lift force, we argue that this force is proportional to a3b, where b is the polar radius, and conclude that the dimensionless lift coefficient of the oblate spheroid does not depend on b and is equal to that of the sphere of radius a.
A highly sensitive imaging polarimeter in the x-ray regime
Authors: Grabiger Benjamin , Marx-Glowna Berit , Uschmann Ingo , Loetzsch Robert , Paulus Gerhard G. , Schulze Kai S.
Published: November 2020

We report on the development of a highly sensitive imaging polarimeter that allows for the investigation of polarization changing properties of materials in the x-ray regime. By combining a microfocus rotating anode, collimating multilayer mirrors, and two germanium polarizer crystals, we achieved a polarization purity of the two orthogonal linear polarization states of 8 × 10−8. This enables the detection of an ellipticity on the same order or a rotation of the polarization plane of 6 arcsec. The high sensitivity combined with the imaging techniques allows us to study the microcrystalline structure of materials. As an example, we investigated beryllium sheets of different grades, which are commonly used for fabricating x-ray lenses, with a spatial resolution of 200 μm, and observed a strong degradation of the polarization purity due to the polycrystalline nature of beryllium. This makes x-ray lenses made of beryllium unsuitable for imaging polarimeter with higher spatial resolution. The results are important for the development of x-ray optical instruments that combine high spatial resolution and high sensitivity to polarization.
Aerographite phonon density of states affects double resonant Raman scattering
Authors: Zhang Hao , Horvat Joseph , Lewis R. A. , Adelung Rainer , Fiedler Bodo , Mishra Yogendra K.
Published: November 2020

Raman spectra of aerographite, graphite oxide, graphite flakes, and kish graphite were investigated with different laser excitation energies (wavelengths, λL), namely, 2.81 eV (442 nm), 2.41 eV (514 nm), 2.33 eV (532 nm), and 1.96 eV (633 nm). X-ray diffraction analysis showed that aerographite and graphite oxide are structurally disordered. The Raman spectra of both exhibit typical graphitic features, namely, G, D, D′, and 2D bands. The D and 2D bands exhibit a “blue-shift” with laser excitation energies, EL, while the G bands remain invariant. The intensity ratio between the D and G bands (ID/IG) ranges from 0.70 to 1.25 for aerographite and graphite oxide and from 0.04 to 0.24 for graphite flakes and kish graphite. The dependence of ID/IG on λL4 is linear for graphite flakes and kish graphite, while it saturates at the longest λL for aerographite and graphite oxide. A physical explanation of this unexpected saturation is proposed within the double resonant Raman scattering model, taking into account the disorder-induced changes of the phonon density of states.
A note on a swirling squirmer in a shear-thinning fluid
Authors: Nganguia H. , Zheng K. , Chen Y. , Pak O. S. , Zhu L.
Published: November 2020

Micro-organisms and artificial microswimmers often move in biological fluids displaying complex rheological behaviors, including viscoelasticity and shear-thinning viscosity. A comprehensive understanding of the effectiveness of different swimming gaits in various types of complex fluids remains elusive. The squirmer model has been commonly used to represent different types of swimmers and probe the effects of different types of complex rheology on locomotion. While many studies focused only on squirmers with surface velocities in the polar direction, a recent study has revealed that a squirmer with swirling motion can swim faster in a viscoelastic fluid than in Newtonian fluids [Binagia et al., J. Fluid Mech. 900, A4, (2020)]. Here, we consider a similar setup but focus on the sole effect due to shear-thinning viscosity. We use asymptotic analysis and numerical simulations to examine how the swirling flow affects the swimming performance of a squirmer in a shear-thinning but inelastic fluid described by the Carreau constitutive equation. Our results show that the swirling flow can either increase or decrease the speed of the squirmer depending on the Carreau number. In contrast to swimming in a viscoelastic fluid, the speed of a swirling squirmer in a shear-thinning fluid does not go beyond the Newtonian value in a wide range of parameters considered. We also elucidate how the coupling of the azimuthal flow with shear-thinning viscosity can produce the rotational motion of a swirling pusher or puller.
Defect profiling in FEFET Si:HfO2 layers
Authors: O'Sullivan B. J. , Putcha V. , Izmailov R. , Afanas'ev V. , Simoen E. , Jung T. , Higashi Y. , Degraeve R. , Truijen B. , Kaczer B. , Ronchi N. , McMitchell S. , Banerjee K. , Clima S. , Breuil L. , Van den Bosch G. , Linten D. , Van Houdt J.
Published: November 2020

Ferroelectric Si-doped HfO2 is a promising candidate for future generation memory devices. However, such devices are vulnerable to significant threshold voltage shifts resulting from charge trapping in oxide defects. We use complementary characterization and modeling techniques to reveal significant electron trapping/de-trapping behavior, together with a strong temperature dependence of the electron emission kinetics in ferroelectric layers, which results from the onset of polarization of the ferroelectric layer. This can lead to an apparent difference in the defect characteristics in ferroelectric-HfO2 compared to the paraelectric-HfO2 structures they are shown to closely resemble when this contribution is decoupled. The results demonstrate the presence of a defect band closely aligned to the silicon conduction band, which can easily be accessed during device operation.
Effect of beam deflection on the thermal responsivity of GaAs-based doubly clamped microelectromechanical beam resonators
Authors: Qiu Boqi , Zhang Ya , Akahane Kouichi , Nagai Naomi , Hirakawa Kazuhiko
Published: November 2020

We have investigated how the beam geometry affects the thermal responsivity of doubly clamped GaAs microelectromechanical systems (MEMS) beam resonator structures. When the MEMS beam is heated, a thermal strain is generated and shifts the resonance frequency. MEMS beams with larger l/h ratios (l and h are the length and the thickness of the MEMS beam, respectively) have lower thermal conductances and are supposed to exhibit higher thermal responsivities. However, the induced thermal strain tends to be released by beam deflection for long GaAs beams, and as a result, long beams do not necessarily lead to high thermal responsivities. To reduce the beam deflection, we have introduced a preloaded tensile strain in the MEMS beam by using the lattice mismatch between GaAs1−xPx (x = 0.01) and GaAs. We find that the deflection of the GaAs1−xPx MEMS beam is suppressed and the responsivities increase with the increasing beam length, demonstrating that the introduction of tensile strain is useful for achieving high thermal responsivities predicted for long MEMS beams.
Thermocapillary instabilities in a liquid layer subjected to an oblique temperature gradient: Effect of a prescribed normal temperature gradient at the substrate
Authors: Patne Ramkarn , Agnon Yehuda , Oron Alexander
Published: November 2020

We consider thermocapillary instability in a three-dimensional liquid layer with a deformable interface with an ambient gas phase and subjected to an oblique temperature gradient when the temperature gradient at the substrate is prescribed. We demonstrate that this configuration leads to a drastic change in the instability features with respect to those emerging when either a purely vertical temperature gradient (VTG) or a purely horizontal temperature gradient (HTG) is present. In the case of the return flow as the base state, the spanwise long-wave instability mode dominates except for the range of small Bond numbers Bo. Slippage at the substrate has a stabilizing (destabilizing) effect on streamwise (spanwise) long-wave modes in the presence of a HTG. In the case of linear flow as the base state, both streamwise and spanwise long-wave modes play a major role in the instability onset depending on the ratio between the HTG and the VTG η for higher values of the capillary number Ca, e.g., Ca > 0.001. However, for lower values of Ca, e.g., Ca < 0.001, streamwise and spanwise instability modes become finite-waves at large η. In contrast to the return flow, for the linear flow, slippage at the substrate destabilizes both long-wave modes.
Deep learning methods for super-resolution reconstruction of temperature fields in a supersonic combustor
Authors: Kong Chen , Chang Jun-Tao , Li Yun-Fei , Chen Ruo-Yu
Published: November 2020

A general super-resolution (SR) reconstruction strategy is proposed to address the super-resolution reconstruction of temperature fields from low-resolution coarse temperature field data using convolutional neural networks. Two deep learning (DL) models were applied to augment the spatial resolution of temperature fields. One is the classical super-resolution convolutional neural network, and the other is the novel multiple path super-resolution convolutional neural network (MPSRC). Three paths with and without a pooling layer are designed in the MPSRC to fully capture spatial distribution features of temperature. Numerical simulations of combustion in a strut scramjet combustor at various Mach numbers are carried out to establish a dataset for network training and testing. The corresponding high-resolution temperature fields were successfully reconstructed with remarkable accuracy. The reconstruction performances of those models were comprehensively investigated and compared with the bicubic interpolation method. The results demonstrated that both DL methods can greatly improve the super-resolution reconstruction accuracy and the MPSRC can provide a better reconstruction result with a lower mean square error and a higher peak signal-to-noise ratio.
Covalency in Fe2O3 and FeO: Consequences for XPS satellite intensity
Authors: Bagus Paul S. , Nelin Connie J. , Brundle C. R. , Vincent Crist B. , Lahiri N. , Rosso Kevin M.
Published: November 2020

The covalent character of the interaction between the metal cation and the oxygen ligands has been examined for two Fe oxides with different nominal oxidation states, Fe(II)O, and Fe(III)2O3. The covalent character is examined for the initial, ground state configuration and for the ionic states involving the removal of a shallow core, Fe 3p, and a deep core, Fe 2p, electron. The covalency is assessed based on novel theoretical analyses of wave functions for the various cases. It is found that the covalency is considerably different for different oxidation states and for different ionized and non-ionized configurations. The changes in covalency for the ions are shown to be responsible for important changes in relaxation energies for X-Ray Photoelectron Spectroscopy (XPS) spectra and in the intensity lost from main XPS peaks to shake satellites. While these consequences are not observables themselves, they are important for the interpretation of the XPS spectra, in particular, for efforts to extract stoichiometries of these iron oxides from XPS data. This is a finding likely applicable across various 3d transition metal oxide materials.
Statistic analysis of lightning transients on wind turbines
Authors: Zhang Yongzheng , Zhang Xiaoqing
Published: November 2020

In view of the actual random behavior of lightning strikes, an efficient algorithm is proposed in this paper for statistical analysis of the lightning transients on wind turbines. The equivalent circuits are established for blades, moving contact site, tower and grounding arrangement. A set of formulas is provided for evaluating their respective circuit parameters. With the equivalent circuits connected in sequence, a complete circuit model of wind turbines (WTs) is constructed for calculating lightning transients. The lightning transient responses can be obtained at different locations on a wind turbine by using the circuit model to perform the transient calculation. For checking the validity of the circuit model, the experiment measurement is also made on a laboratory-scale WT. An approximate match appears between the measured and calculated results. On the basis of the circuit model, the transient calculation is performed sequentially for each discrete amplitude in a large interval of lightning current. The random distribution of lightning current is taken into account by a cumulative probability function of exponential type. The corresponding probability density function is derived to weight the peak values of the lightning transient responses. The statistical values of the lightning transient responses can be determined by totalizing the weighted peak values in the interval of lightning current. Then, a case study is carried out to contrast the statistical values with the non-statistical ones calculated from the standard lightning current amplitudes, and a significant difference is discovered between them.
Natural circulation pump with asymmetrical heat transfer wall as the element of Büttiker–Landauer thermal ratchet
Authors: Sugioka Hideyuki , Someya Yusuke
Published: November 2020

Technology that makes use of waste heat or low-grade energy is important for addressing worldwide energy security concerns. This study proposes the application of a natural circulation pump employing an asymmetrical heat transfer wall as the element of a Büttiker–Landauer (BL) thermal ratchet powered by waste heat. Furthermore, experiments for evaluating the proposed arrangement’s performance were conducted. We demonstrated experimentally that we can realize water circulation in a channel owing to the localized non-equilibrium nature of the pump’s asymmetrical heat transfer wall. In addition, we propose a framework for evaluating the pump’s performance. Our proposal is expected to result in the uptake of practical applications for BL ratchets.
Optimization and Plant Validation of BWRO Operation
Authors: Li Mingheng
Published: November 2020

Optimal plant operation of brackish water reverse osmosis (BWRO) desalination is studied in this chapter. A system-level mathematical model, which explicitly accounts for pump characteristic curves, pressure drops along each pressure vessel, and local water fluxes, is developed and validated by data collected in a desalination plant in Chino, California. A constrained nonlinear optimization is formulated and solved for two RO trains with different service times. It is demonstrated that a 10% reduction in energy consumption can be achieved while maintaining the same permeate flow rate by adjusting operating conditions as suggested by the model. Furthermore, an opportunity for significant savings in disposal cost is identified due to a reduction in brine volume. For multiple RO trains with different service times, the overall energy consumption may be reduced by optimally allocating the permeate rates. A unified model is developed to explain the similarities and differences between BWRO and seawater RO (SWRO).
Batch Operation of RO and PRO
Authors: Li Mingheng
Published: November 2020

Optimal control theory is applied to dynamic operation of batch reverse osmosis (RO) for seawater desalination and batch pressure retarded osmosis (PRO) for power generation. It is proved that the water flux should be constant during the entire operation in order to minimize specific energy consumption (SEC) in RO or to maximize specific energy production (SEP) in PRO. A dimensionless parameter γ = Am Lp π0 tf / V0, similar to the one used in continuous osmoticmembrane processes, is proposed to characterize the energy performance. While the SEC in RO is a monotonic function of recovery and γ, the SEP in PRO is solely a monotonic function of γ. It is shown that batch RO/PRO excels continuous RO/PRO because it mitigates the spatial variation of flux in a long pressure vessel observed in the latter. The batch operation provides an elegant way to implement continuous multistage RO with interstage pumps and an energy recovery device (ERD) as well as continuous multi-stage PRO with interstage turbines. Some tradeoff between energy efficiency and flux is deemed necessary. A preliminary cyclic diagram to operate the batch PRO is proposed.
Corrigendum to: Epidemic poliomyelitis, post-poliomyelitis sequelae and the eradication program
Authors: Peel Margaret M
Published: November 2020

Epidemics of paralytic poliomyelitis (polio) first emerged in the late 19th and early 20th centuries in the United States and the Scandinavian countries. They continued through the first half of the 20th century becoming global. A major epidemic occurred in Australia in 1951 but significant outbreaks were reported from the late 1930s to 1954. The poliovirus is an enterovirus that is usually transmitted by the faecal–oral route but only one in about 150 infections results in paralysis when the central nervous system is invaded. The Salk inactivated polio vaccine (IPV) became available in Australia in 1956 and the Sabin live attenuated oral polio vaccine (OPV) was introduced in 1966. After decades of stability, many survivors of the earlier epidemics experience late-onset sequelae including post-polio syndrome. The World Health Organization launched the global polio eradication initiative (GPEI) in 1988 based on the easily administered OPV. The GPEI has resulted in a dramatic decrease in cases of wild polio so that only Pakistan and Afghanistan report such cases in 2020. However, a major challenge to eradication is the reversion of OPV to neurovirulent mutants resulting in circulating vaccine-derived poliovirus (cVDPV). A novel, genetically stabilised OPV has been developed recently to stop the emergence and spread of cVDPV and OPV is being replaced by IPV in immunisation programs worldwide. Eradication of poliomyelitis is near to achievement and the expectation is that poliomyelitis will join smallpox as dreaded epidemic diseases of the past that will be consigned to history.
Molecular and isotopic evidence reveals the end-Triassic carbon isotope excursion is not from massive exogenous light carbon
Authors: Fox Calum P. , Cui Xingqian , Whiteside Jessica H. , Olsen Paul E. , Summons Roger E. , Grice Kliti
Published: November 2020

Significance

The end-Triassic mass extinction that occurred ∼202 Ma is one of the “Big Five” biotic crises of the Phanerozoic Eon. It is also accompanied by an organic carbon isotopic excursion that has long been interpreted as the result of a global-scale carbon-cycle disruption. Rather than being due to massive inputs of exogenous light carbon into the ocean–atmosphere system, the isotopic excursion is shown here to reflect regional sea-level change that caused a transition from a marine ecosystem to a less saline, shallow-water, microbial-mat environment and resultant changes in the sources of organic matter. The mass extinction that occurred slightly later, caused by abrupt injection of volcanogenic CO
2
, is accompanied by only modest changes in organic carbon isotopic composition.
Heterogeneity in social and epidemiological factors determines the risk of measles outbreaks
Authors: Bosetti Paolo , Poletti Piero , Stella Massimo , Lepri Bruno , Merler Stefano , De Domenico Manlio
Published: November 2020

Significance

The recent increase in large-scale migration trends generates several concerns about public health in destination countries, especially in the presence of massive incoming human flows from countries with a disrupted healthcare system. Here, we analyze the flow of 3.5 M Syrian refugees toward Turkey to quantify the risk of measles outbreaks. Our results suggest that heterogeneity in immunity, population distribution, and human-mobility flows is mostly responsible for such a risk: In fact, adequate policies of social integration and vaccine campaigns provide the most effective strategies to reduce measles disease risks for both migrant and hosting populations.
Stable metal anodes enabled by a labile organic molecule bonded to a reduced graphene oxide aerogel
Authors: Gao Yue , Wang Daiwei , Shin Yun Kyung , Yan Zhifei , Han Zhuo , Wang Ke , Hossain Md Jamil , Shen Shuling , AlZahrani Atif , van Duin Adri C. T. , Mallouk Thomas E. , Wang Donghai
Published: November 2020

Significance

Rechargeable batteries based on metal anodes are highly desirable due to their high energy density. However, the electrochemical interface is generally not favorable for metal deposition, resulting in dendritic metal growth and an unstable solid–electrolyte interphase (SEI). We altered the interface using a labile organic molecule, benzenesulfonyl fluoride. This molecule was bonded to the surface of a reduced graphene oxide aerogel, which not only guides uniform metal deposition but also enables formation of a stable SEI layer. The lithium metal batteries showed stable cycling and excellent tolerance to low-temperature operation. Stable sodium and zinc anodes were also realized, demonstrating the versatility of this concept.
From antiferromagnetic and hidden order to Pauli paramagnetism in U
M
2
Si
2
compounds with 5
f
electron duality
Authors: Amorese Andrea , Sundermann Martin , Leedahl Brett , Marino Andrea , Takegami Daisuke , Gretarsson Hlynur , Gloskovskii Andrei , Schlueter Christoph , Haverkort Maurits W. , Huang Yingkai , Szlawska Maria , Kaczorowski Dariusz , Ran Sheng , Maple M. Brian , Bauer Eric D. , Leithe-Jasper Andreas , Hansmann Philipp , Thalmeier Peter , Tjeng Liu Hao , Severing Andrea
Published: November 2020

Significance

The interplay of band-formation and electron-correlation effects in uranium heavy fermion compounds is the subject of an ongoing debate. Here unexpected insight has been gained from advanced spectroscopies on isostructural members of the U

M

2

S
i

2

family with different properties. The antiferromagnetic (

M

= Pd,Ni), hidden order (

M

= Ru), and Pauli-paramagnetic (

M

= Fe) compounds all exhibit atomic-like U 5

f

2

multiplet states with singlet–singlet (quasi-doublet) symmetry while the U 5

f

3

weight increases from Pd

→

Ni

→

Ru

→

Fe, indicating increasing itineracy. This reveals the dual nature of the U-5
f
electrons throughout the family; the local aspects persist in the hidden-order compound

U
R
u

2

S
i

2

and surprisingly even in the highly itinerant Pauli paramagnet

U
F
e

2

S
i

2

. This study gives guidelines for the theoretical treatment of U intermetallic systems.
Incompatibility between proliferation and plant invasion is mediated by a regulator of appressorium formation in the corn smut fungus
Ustilago maydis
Authors: de la Torre Antonio , Castanheira Sónia , Pérez-Martín José
Published: November 2020

Significance

Many phytopathogenic fungi need specialized structures, called appressoria, to penetrate the plant before infection starts. For these structures, the fungus must carefully control when and where its cells divide, and it has been reported in different fungal phytopathogens that appressorium formation is subordinated to the cell cycle control. However, the molecular details about how this control operates were unknown. We described in the corn smut fungus
U. maydis
that Biz1, a regulator for the formation of appressorium, is phosphorylated by the kinase responsible for cell cycle progression. Biz1 is part of a negative feedback loop responsible for the final decision to invade or not the plant tissue. Targeting this process will lead to the development of antipenetrant fungicides.
Mobile loop dynamics in adenosyltransferase control binding and reactivity of coenzyme B
12
Authors: Mascarenhas Romila , Ruetz Markus , McDevitt Liam , Koutmos Markos , Banerjee Ruma
Published: November 2020

Significance

Coenzyme B
12
(or 5′-deoxyadenosylcobalamin [AdoCbl]) is a cofactor for methylmalonyl-CoA mutase (MCM), which is important for propionate metabolism in
Mycobacterium tuberculosis
and for anaplerosis in humans. AdoCbl is synthesized by adenosyltransferase (ATR), which doubles as an escort, delivering the cofactor to MCM. The mechanism by which this large cofactor is translocated from ATR to MCM is not known. Our crystal structures of
M. tuberculosis
ATR reveal that mobile loops dynamically create a customized pocket to control cofactor coordination and conformation, regulating its reactivity and transportability. These changes also control solvent exposure and signaling to MCM when ATR is ready to transfer cargo, in a process where the cofactor tail plays an important role in the handover between proteins.
Aneuploidy increases resistance to chemotherapeutics by antagonizing cell division
Authors: Replogle John Michael , Zhou Wen , Amaro Adrianna E. , McFarland James M. , Villalobos-Ortiz Mariana , Ryan Jeremy , Letai Anthony , Yilmaz Omer , Sheltzer Jason , Lippard Stephen J. , Ben-David Uri , Amon Angelika
Published: November 2020

Significance

Aneuploidy, or an imbalanced chromosome content, is a hallmark of cancer. Paradoxically, aneuploidy is associated both with poor prognosis in cancer and with slow growth in primary cells. Here, we bridge these two seemingly contradictory observations: the cell cycle defects caused by aneuploidy protect cancer cells from chemotherapeutic damage. Our study may inform treatment decisions by impacting our understanding of how sensitive a particular tumor may be to certain chemotherapies.
TLR signaling adapter BCAP regulates inflammatory to reparatory macrophage transition by promoting histone lactylation
Authors: Irizarry-Caro Ricardo A. , McDaniel Margaret M. , Overcast Garrett R. , Jain Viral G. , Troutman Ty Dale , Pasare Chandrashekhar
Published: November 2020

Significance

Macrophages initiate inflammation to eliminate invading microbes. Following clearance of inflammatory stimuli, macrophages down-regulate inflammatory genes and express repair genes to protect host tissues from damage. Here, we find that the adaptor B-cell adapter for PI3K (BCAP) facilitates this transition of inflammatory macrophages to reparative macrophages. Absence of BCAP in macrophages limits the ability of mice to repair intestinal tissues following inflammatory damage. Following Toll-like receptor stimulation, macrophages undergo aerobic glycolysis that results in lactate production, a process compromised in BCAP-deficient macrophages. This lactate is incorporated into histone tails and is involved in reparative macrophage transition. We find defective lactate production by BCAP-deficient macrophages results in reduced histone lactylation and expression of tissue repair genes, thus blunting their reparative transition.
The changing geography of social mobility in the United States
Authors: Connor Dylan Shane , Storper Michael
Published: November 2020

Significance

Intergenerational social mobility in the United States has declined over the last century, sparking a national debate about how to improve equality of opportunity. By analyzing data spanning the 20th century, we demonstrate strong temporal patterns operating across regions. Some areas of the United States have witnessed significant declines in social mobility, while others have had persistent low levels all along. Thus, the contemporary national picture is shaped by both powerful forces of change that reduce intergenerational mobility in some regions and deeply entrenched long-term forces generating persistence in others. It follows that improving social mobility will be challenging, as policy would need to respond to both forces and do so according to their varying mixture across different regions.
An inactive receptor-G protein complex maintains the dynamic range of agonist-induced signaling
Authors: Jang Wonjo , Adams C. Elizabeth , Liu Heng , Zhang Cheng , Levy Finn Olav , Andressen Kjetil Wessel , Lambert Nevin A.
Published: November 2020

Significance

G protein-coupled receptors (GPCRs) are targeted by a large fraction of approved drugs and regulate many important cellular processes. Conventional signaling by GPCRs is triggered when agonist-activated receptors associate with heterotrimeric G proteins. We found that serotonin 5-HT
7
receptors couple to G
s
proteins in an unconventional manner, in which agonist binding instead promotes dissociation of preexisting inactive 5-HT
7
–G
s
complexes. Therefore, agonists can initiate signaling via two distinct mechanisms, by promoting the association of active receptors and G proteins and by promoting dissociation of inactive receptors and G proteins.
Mammalian-specific ectodermal enhancers control the expression of
Hoxc
genes in developing nails and hair follicles
Authors: Fernandez-Guerrero Marc , Yakushiji-Kaminatsui Nayuta , Lopez-Delisle Lucille , Zdral Sofía , Darbellay Fabrice , Perez-Gomez Rocío , Bolt Christopher Chase , Sanchez-Martin Manuel A. , Duboule Denis , Ros Marian A.
Published: November 2020

Significance

In this study, we report a unique and necessary function for the
HoxC
gene cluster in the development of some ectodermal organs, as illustrated both by the hair and nail phenotype displayed by mice lacking the
Hoxc13
function and by the congenital anonychia (absence of nails) in full
HoxC
cluster mutants. We show that
Hoxc
genes are activated in a colinear manner in the embryonic limb ectoderm and are subsequently transcribed in developing nails and hairs. We identify two mammalian-specific enhancers located upstream of the
HoxC
cluster, which display an exclusive ectodermal specificity. Individual or combined enhancer deletions suggest that they act in combination to raise the transcription level of several
Hoxc
genes during hair and nail development.
NAP1-Related Protein 1 (NRP1) has multiple interaction modes for chaperoning histones H2A-H2B
Authors: Luo Qiang , Wang Baihui , Wu Zhen , Jiang Wen , Wang Yueyue , Du Kangxi , Zhou Nana , Zheng Lina , Gan Jianhua , Shen Wen-Hui , Ma Jinbiao , Dong Aiwu
Published: November 2020

Significance

NAP1 family proteins are evolutionarily conserved and important histone chaperones. However, because histone chaperones are very flexible, determination of their crystal structures, especially when complexed with histones, is very difficult. Here we obtained the co-crystal structure of
Arabidopsis
NAP1-Related Protein 1 (NRP1) and the H2A-H2B heterodimer at 3.0 Å, which led to the discovery of a previously unknown mode of interaction between the NAP1 family and H2A-H2B. Our results provide evidence of multiple interaction modes of a NAP1-family histone chaperone, thereby shedding light on how histone chaperones effectively shield H2A-H2B from nonspecific interaction with DNA.