bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison and calibration of different electroporation models. Application to rabbit livers experiments
Authors: Jankowiak Gaspard , Taing Cécile , Poignard Clair , Collin Annabelle
Published: June 2020

Electroporation is a complex phenomenon that occurs when biological tissues are subjected to electric pulses. The clinical interest for the phenomenon has constantly increased for the last decades. Indeed, electroporation makes it possible to either kill directly the cells in the target region (tumor) or to introduce molecules into living cells. However, one of the main limitation of using electroporation in the clinical routine comes from the technical difficulties raised by such therapies, in particular it is difficult to well determine the treated zone. Numerical modeling of the electric field magnitude could provide a powerful strategy to assess the treatment efficacy: thanks to well-designed models, the computation of the distribution of the electric field is achievable, providing a numerical evaluation of the treatment. The main objective of this work is to go further on the patient-adapted numerical modeling of the electric field magnitude by laying the ground of the possible electroporation models - which will be compared qualitatively - and their calibrations. This will be done in the framework of bioelectrical measurements on rabbit livers that come from the literature.
Schmerzpatienten in Bewegung bringen
Authors: Lotze Martin , Moseley G. Lorimer
Published: June 2020

Das komplexe regionale Schmerzsyndrom (CRPS) ist durch unerträgliche und meist wechselnde, brennende oder ziehende Schmerzen charakterisiert. Etwa 65 000 Patienten sind in Deutschland von dieser Krankheit betroffen. Eine wirksame Strategie ist das stufenweise Imaginationstraining (GMI).
Nicht-invasive Hirnstimulation als Behandlungsverfahren bei
Essstörungen – ein narrativer Überblick
Authors: Schag Kathrin , İnce Başak , Zipfel Stephan , Max Sebastian , Plewnia Christian , Giel Katrin
Published: June 2020

Ziel Therapieerfolge in der Essstörungsbehandlung sind oft
eingeschränkt und nicht nachhaltig. Daher besteht weiterhin
großer Bedarf an der Weiterentwicklung von vorliegenden
Behandlungsangeboten und innovativen Therapieansätzen.
Nicht-invasive Hirnstimulation (NIHS) ist ein innovativer Ansatz, der bei
Patientinnen mit Essstörungen (ES) seit kurzem eingesetzt wird. Der
vorliegende Artikel gibt einen narrativen Überblick über die
am häufigsten eingesetzten Stimulationsverfahren sowie die aktuelle
Studienlage bezüglich ihrer Wirksamkeit in der Behandlung.

Methodik Wir haben eine Literaturrecherche in der PubMed-Datenbank zu
dem Thema NIHS bei ES durchgeführt und dabei 32 relevante Artikel
identifiziert. Nur 9 dieser Artikel beschreiben empirische Studien an
Patientinnen mit ES.

Ergebnisse Die Studien wurden an Patientinnen mit verschiedenen
ES-Diagnosen, mit unterschiedlichen Behandlungszielen, unterschiedlichen
Stimulationstechniken und Unterschieden in Häufigkeit, Dauer und
Intensität der Stimulation durchgeführt. Einige, aber nicht
alle Studien weisen auf Verbesserungen in den jeweils untersuchten
ES-Symptomen, z. B. der Reduktion des Verlangens nach Nahrung, des
restriktiven Essverhaltens und ES-bezogener Kognitionen hin.

Diskussion Es liegen nur wenige Studien vor, die den Einsatz von NIHS
bei ES beschreiben. Die Studienlage ist sehr heterogen. Insgesamt sprechen
die Befunde dafür, dass NIHS einen vielversprechenden
Behandlungsansatz für ES darstellt.
Aspectos genéticos nas afecções do ombro
Authors: Cohen Carina , Figueiredo Eduardo A. , Belangero Paulo S. , Andreoli Carlos Vicente , Leal Mariana Ferreira , Ejnisman Benno
Published: June 2020

A influência da herança genética tem sido cada vez mais investigada nas afecções do ombro, como a lesão do manguito rotador, instabilidade e ombro congelado. Ainda que os achados iniciais sejam pouco esclarecedores, é necessário construir progressivamente um banco de marcadores genéticos para catalogar perfis genômicos que, mais adiante, poderão contribuir para a previsão do risco da doença, desenvolvimento de melhores ferramentas de diagnóstico e tratamento. O presente artigo busca atualizar o que há de evidências de estudos genéticos na literatura para essas doenças, desde análises de polimorfismos, expressão de genes candidatos em tecidos e estudos de associação genômica ampla (GWAS, na sigla em inglês). Porém, é necessário apontar que existe grande dificuldade na replicação e utilização dos achados, principalmente em razão da falta de poder estatístico, da alta taxa de resultados falso-positivos e da grande quantidade de variáveis envolvidas.
Azidation of Partially Protected Carbohydrate Derivatives: Efficient Suppression of Acyl Migration
Authors: Kononov Leonid O. , Stepanova Elena V. , Zinin Alexander I. , Abronina Polina I. , Chizhov Alexander O.
Published: June 2020

Although azidation by nucleophilic substitution is widely used in organic chemistry, it has a limitation for partially protected carbohydrate derivatives under typical reaction conditions used for azidation (heating with NaN3, phase-transfer catalyst (optional), DMF or DMSO) as it can cause substantial migration (70%) of O-acyl protective groups. Several approaches, including the use of a temporary protective group for the unprotected hydroxyl group, to avoid acyl migration have been compared. Addition of excess of ethyl trifluroacetate effectively suppressed benzoyl migration but inhibited substitution of the chlorine atom with the azido group. The most robust procedure involved addition of excess n-butyl formate to the reaction mixture. When this protocol was followed, migration of benzoyl groups in lactose derivatives with free hydroxy group at C-3′ or C-4′ was reduced to 4%, with the yield of the target, partially protected derivatives with an azido group in the aglycone approaching 92%.
Parafusos pediculares e violação facetária – A importância do ângulo entre a faceta e o parafuso
Authors: Amaral Rodrigo , Pimenta Luiz , Netto Angelo Guarçoni , Pokorny Gabriel Henrique , Fernandes Raquel
Published: June 2020

Objetivo Verificar se, independente da técnica de colocação do parafuso, há uma distância ou angulação segura em relação as facetas para que os parafusos sejam colocados de modo a evitar a violação da articulação facetária.

Métodos Estudo retrospectivo, comparativo, não randomizado, em centro único. Foram avaliados em tomografia computadorizada axial: o ângulo do parafuso/barra em relação a linha média, o ângulo do centro das facetas em relação a linha média, a distância entre a cabeça do parafuso/barra até a linha média, e a distância do centro das facetas até a linha média; a violação da articulação facetária será avaliada em uma gradação de 0 a 2. Serão também calculados a diferença entre o ângulo do parafuso e ângulo da faceta (Δ Ångulo) e também a diferença entre a distância da faceta e a distância do parafuso (Δ Distância).

Resultados Um total de 212 pacientes e 397 facetas foram analisados (196 do lado esquerdo e 201 do lado direito). Destes, 303 foram não violados (grau 0), correspondendo a 76,32%, e 94 sofreram algum tipo de violação (grau 1 e 2), correspondendo a 23,68%. A média do Δ ângulo foi de 9,87° +/−  4,66° (grau 0) e de 3,77° +/−  4,93° em facetas (grau 1 e 2) (p < 0.001), e o Δ distância médio nos casos em que não houve violação foi de 0,94 unidades aleatórias (u.a.) +/− 0,39 u.a., enquanto o Δ distância de casos G1 e G2 foi de 0,56 u.a. +/−  0,25 u.a. (p < 0.001).

Conclusão As medidas de ângulo e distância entre faceta e parafuso, podem auxiliar na colocação de parafusos. Esses parâmetros podem ser utilizados como medidas de segurança com o uso mais frequentes das técnicas de navegação cirúrgica.
Can we detect clusters of chaotic dynamical networks via causation entropy?
Authors: Canlı Özge , Günel Serkan
Published: June 2020

It is known that chaotic dynamical systems in the coupled networks can synchronize, and they can even form clusters. Our study addresses the issue of determining the membership information of continuous-time dynamical networks forming clusters. We observe the output vectors of individual systems in the networks and reconstruct the state space according to Takens’ embedding theorem. Afterward, we estimate the information-theoretic measures in the reconstructed state space. We propose the average integrated causation entropy as a model-free distinctive measure to distinguish the clusters in the network using the k-means clustering algorithm. We have demonstrated the proposed procedure on three networks that contain Chua systems. The results indicate that we can determine the members of clusters and the membership information from the data, conclusively.
Interfacial rigidity and topology of reverse microemulsions: Influence of alcohol molecules
Authors: Geethu P. M. , Aswal Vinod K. , Satapathy Dillip K.
Published: June 2020

Using dielectric relaxation spectroscopy and small-angle neutron scattering techniques, we present a quantitative analysis of the influence of short-chain (ethanol) and long-chain (octanol) alcohol molecules on the elastic bending constants of AOT [sodium-1,4-bis(2-ethylhexoxy)-1,4-dioxobutane-2-sulfonate]-stabilized reverse microemulsions. A significant increase in the elastic bending rigidity, κ, of the AOT surfactant layer (30.7%) is observed with the inclusion of octanol, whereas a decrease in κ amounting to 11.2% is obtained in the presence of ethanol. The experimentally elusive saddle-splay modulus, κ¯, of alcohol-loaded microemulsions is determined using a novel approach. Notably, the ratio κ¯/κ lies in the range −2<κ¯/κ<0, which is acceptable for spherical microemulsion droplets. Further, the presence of ethanol molecules causes a decrease in the percolation threshold temperature owing to an increase in the fluidity of the surfactant monolayer at the oil–water interface. On the other hand, the addition of octanol molecules shifts the percolation threshold to higher temperatures implying a further reinforcement of the surfactant film.
Non-Boltzmann vibrational energy distributions and coupling to dissociation rate
Authors: Singh Narendra , Schwartzentruber Thomas
Published: June 2020

In this article, we propose a generalized model for nonequilibrium vibrational energy distribution functions. The model can be used, in place of equilibrium (Boltzmann) distribution functions, when deriving reaction rate constants for high-temperature nonequilibrium flows. The distribution model is derived based on the recent ab initio calculations, carried out using potential energy surfaces developed using accurate computational quantum chemistry techniques for the purpose of studying air chemistry at high temperatures. Immediately behind a strong shock wave, the vibrational energy distribution is non-Boltzmann. Specifically, as the gas internal energy rapidly excites to a high temperature, overpopulation of the high-energy tail (relative to a corresponding Boltzmann distribution) is observed in ab initio simulations. As the gas excites further and begins to dissociate, a depletion of the high-energy tail is observed, during a time-invariant quasi-steady state. Since the probability of dissociation is exponentially related to the vibrational energy of the dissociating molecule, the overall dissociation rate is sensitive to the populations of these high vibrational energy states. The non-Boltzmann effects captured by the new model either enhance or reduce the dissociation rate relative to that obtained assuming a Boltzmann distribution. This article proposes a simple model that is demonstrated to reproduce these non-Boltzmann effects quantitatively when compared to ab initio simulations.
Achromatic gradient-index phononic crystal lenses with unique acoustic applications
Authors: Mandel Savannah
Published: June 2020

Thanks to a method known as topology optimization, gradient-index phononic crystal lenses may have applications such as imaging, energy harvesting and wireless power transfer.
Homogenization of acoustic metamaterials using retrieval methods
Authors: Roux Laetitia , Croënne Charles , Audoly Christian , Hladky-Hennion Anne-Christine
Published: June 2020

The effective properties of two-dimensional acoustic metamaterials are here obtained by applying two retrieval methods, referred to as the direct inversion method and the differential method. They employ the scattering coefficients at the incidence and transmission sides of the global systems immersed in a fluid. A validation case study on a one-dimensional periodic design is first presented. A two-dimensional design comprising periodic cylindrical steel inclusions in a soft elastic matrix is then examined. Homogenization issues related to different underlying assumptions in the two retrieval methods are discussed. It is shown that one of the retrieval methods (the differential method) well describes the interior of the medium, away from the interfaces, while the other (the direct inversion method) captures the interface effects. The two retrieval methods are used to build homogeneous equivalent media which are used to predict scattering coefficients. A hybrid method is introduced which combines the two methods to create effective media that are accurate approximations of their 2D counterparts.
Unambiguous evidence of three coexisting ferroelectric phases in a lead-free LixNa1−xNbO3 system
Authors: Singh Abhinav Kumar , Dubey Digvijay Nath , Singh Gurvinderjit , Tripathi Saurabh
Published: June 2020

We report here the presence of three coexisting ferroelectric phases in a lead-free lithium sodium niobate (Lix Na1−xNbO3; LNNx) system stable for 0.15≤x≤0.80, which contrasts the review report of Dixon and Lightfoot [Phys. Rev. B 97, 224105 (2018)]. More importantly, we have identified LNN20 as an important composition for technological applications due to its high dielectric permittivity, low loss, and high ferroelectric response. The anomalous dielectric and ferroelectric responses in LNN20 have been attributed to the morphotropic phase boundary like nature around this composition.
Significant enhancement of magnetocaloric effect in a NiMnCuGa Heusler alloy through textural modification
Authors: McLeod M. V. , Bayer D. , Turgut Z. , Giri A. K. , Majumdar B. S.
Published: June 2020

Magnetocaloric materials are of increasing interest to bring magnetic refrigeration to everyday households and drastically impact the energy demands for temperature control devices. In this work, a polycrystalline Heusler alloy of composition Ni2Mn0.76Cu0.24Ga with coinciding structural and magnetic transformation temperatures was subjected to compressive stress assisted thermal cycling (SATC) to enhance the magnetic properties by inducing a preferred orientation in the martensite. Isofield magnetization measurements showed a sharpening of the transformation between ferromagnetic martensite and paramagnetic austenite due to SATC. In isothermal magnetization measurements, SATC was seen to increase the magnetostructural coupling. With a 2 T applied magnetic field, the magnetocaloric effect (MCE) increased from ∼10 to ∼25 J/kg K and the refrigeration capacity (RC) almost doubled due to SATC. Heat capacity measurements were largely unaffected by SATC. The change in adiabatic temperature was estimated by using Cp and change in magnetic entropy (ΔSM) calculations. SATC was seen to increase ΔTad from ∼1.2 K to 2 K for an applied magnetic field of 2 T. Neutron diffraction measurements revealed highly textured martensite in the as received state that rotated to a more ideal preferred orientation after SATC that enhanced the magnetostructural transformation; and thus, improving the MCE and ΔTad.
The tipping times in an Arctic sea ice system under influence of extreme events
Authors: Yang Fang , Zheng Yayun , Duan Jinqiao , Fu Ling , Wiggins Stephen
Published: June 2020

In light of the rapid recent retreat of Arctic sea ice, the extreme weather events triggering the variability in Arctic ice cover has drawn increasing attention. A non-Gaussian α-stable Lévy process is thought to be an appropriate model to describe such extreme events. The maximal likely trajectory, based on the nonlocal Fokker–Planck equation, is applied to a nonautonomous Arctic sea ice system under α-stable Lévy noise. Two types of tipping times, the early-warning tipping time and the disaster-happening tipping time, are used to predict the critical time for the maximal likely transition from a perennially ice-covered state to a seasonally ice-free one and from a seasonally ice-free state to a perennially ice-free one, respectively. We find that the increased intensity of extreme events results in shorter warning time for sea ice melting and that an enhanced greenhouse effect will intensify this influence, making the arrival of warning time significantly earlier. Meanwhile, for the enhanced greenhouse effect, we discover that increased intensity and frequency of extreme events will advance the disaster-happening tipping time, in which an ice-free state is maintained throughout the year in the Arctic Ocean. Finally, we identify values of the Lévy index α and the noise intensity ϵ in the αϵ-space that can trigger a transition between the Arctic sea ice state. These results provide an effective theoretical framework for studying Arctic sea ice variations under the influence of extreme events.
Laser-induced fluorescence measurement of very slow neutral flows in a dusty plasma experiment
Authors: Marshall R. S. , Bellan P. M.
Published: June 2020

Laser-Induced Fluorescence (LIF) provides the temperature and flow velocity of a target species by direct measurement of its velocity distribution via Doppler shift. A LIF diagnostic has been developed at the Caltech water–ice dusty plasma experiment that uses an ultra-narrow tunable diode laser to pump the λvac = 696.735 nm argon neutral transition. A photomultiplier detects fluorescence emission at λvac = 772.633 nm. Signal to noise ratios in excess of 100 are achieved along with a high degree of reproducibility between measurements. A Labview program fully automates data collection throughout the three-dimensional plasma volume by controlling four stepper motors and recording measured data. The argon neutral temperature is measured to be slightly above room temperature. Challenges such as the lack of absolute calibration of diode lasers and wavelength drift due to slight changes in ambient room conditions are overcome to measure bulk neutral flow speeds on the order of 1–2 m/s with resolution on the order of 2/3 of a meter per second. High-speed video shows that introducing an argon flow to a cloud of ice grains causes the cloud of ice grains to move and change shape. Ice grain motion is analyzed and found to be in agreement with neutral LIF flow measurements. Surprisingly, when the flow ceases, the ice grain cloud reverts to its original location and shape.
Surface dynamics measurement on a gold based metallic glass
Authors: Cao C. R. , Yu L. , Perepezko J. H.
Published: June 2020

The surface diffusion kinetics has been measured on an Au60Cu15.5Ag7.5Si17 metallic glass using the method of surface grating decay from room temperature up to 20 K below the glass transition temperature (Tg). In the early stage of grating decay, the surface diffusion coefficients were estimated as varying in the range of 10−20 to 10−18 m2/s and the corresponding average activation energy is about 0.67  eV. During longer annealing, times the surface grating decay rate slowed down significantly. The slowing of the initial decay was a result of the surface dynamics and influenced by the surface segregation of silicon at a long time, which induced a surface crystallization of a silicon-rich phase.
Structured illumination microscopy using digital micro-mirror device and coherent light source
Authors: Li Meiqi , Li Yaning , Liu Wenhui , Lal Amit , Jiang Shan , Jin Dayong , Yang Houpu , Wang Shu , Zhanghao Karl , Xi Peng
Published: June 2020

Structured illumination microscopy (SIM) achieves doubled spatial resolution through exciting the specimen with high-contrast, high-frequency sinusoidal patterns. Such an illumination pattern can be generated by laser interference or incoherent structured patterns. Opto-electronic devices, such as a Spatial Light Modulator (SLM) or a Digital Micro-mirror Device (DMD), can provide rapid switch of illumination patterns for SIM. Although the DMD is much more cost-effective than the SLM, it was previously restricted in association with incoherent light sources, as its diffractive orders are related to the incident angle and the wavelength of coherent incidence. To extend its application with coherent illumination, here, we model the DMD as a blazed grating and simulate the effect with DMD pattern changes in the SIM. With careful analysis of the illumination contrast along different angles and phases, we report a fast, high-resolution, and cost-efficient SIM with DMD modulation. Our home-built laser interference-based DMD-SIM (LiDMD-SIM) reveals the nuclear pore complex and microtubule in mammalian cells with doubled spatial resolution. We further proposed the multi-color LiDMD-SIM concept by jointly employing the DMD ON/OFF states with different incident angles for different wavelengths, with high contrast and maximum resolution enhancement.
Evidence for biquadratic exchange in the quasi-two-dimensional antiferromagnet FePS3
Authors: Wildes A. R. , Zhitomirsky M. E. , Ziman T. , Lançon D. , Walker H. C.
Published: June 2020

FePS3 is a van der Waals compound with a honeycomb lattice that is a good example of a two-dimensional antiferromagnet with Ising-like anisotropy. Neutron spectroscopy data from FePS3 were previously analyzed using a straightforward Heisenberg Hamiltonian with a single-ion anisotropy. The analysis captured most of the elements of the data; however, some significant discrepancies remained. The discrepancies were most obvious at the Brillouin zone boundaries. The data are subsequently reanalyzed, allowing for unequal exchange between nominally equivalent nearest-neighbors, which resolves the discrepancies. The source of the unequal exchange is attributed to a biquadratic exchange term in the Hamiltonian, which most probably arises from a strong magnetolattice coupling. The new parameters show that there are features consistent with Dirac magnon nodal lines along certain Brillouin zone boundaries.
Domain walls in antiferromagnets: The effect of Dzyaloshinskii–Moriya interactions
Authors: Conzelmann Teo , Selzer Severin , Nowak Ulrich
Published: June 2020

We investigate domain walls in antiferromagnets focusing on the effect of Dzyaloshinskii–Moriya interactions (DMIs). Using spin model simulations and analytical arguments within a continuum theory, we show that Dzyaloshinskii–Moriya interactions affect static as well as dynamic properties of the domain wall. For certain configurations of the DMI vectors, the DMI can either tilt the easy plane of the domain wall, an effect that leads to a reduced domain wall width, or it can favor a certain chirality of the domain wall. Depending on the DMI configuration, the DMI may lead to an increasing or decreasing domain wall velocity. The asymmetry of the domain wall velocity observed in ferromagnets subject to DMI cannot be found in antiferromagnetic systems.
Achromatic acoustic gradient-index phononic crystal lens for broadband focusing
Authors: Hyun Jaeyub , Cho Wan-Ho , Park Choon-Su , Chang Jiho , Kim Miso
Published: June 2020

The aim of this study is to realize an achromatic acoustic gradient-index (GRIN) phononic crystal (PC) lens system with a spatially invariant focal length over a broad operating frequency range. To this end, we propose an approach of introducing thin achromatic coating layers that can be easily assembled into the front and rear regions of the acoustic GRIN PC lens. A systematic design method based on topology optimization (TO) is developed to inversely design the achromatic coating components. The topology-optimized achromatic coating components are fabricated using 3D printing and coupled with the acoustic GRIN PC lens for acoustic characterization. Both numerical simulation and experimental characterization demonstrate the achromatic focusing capabilities of the GRIN PC lens with the designed achromatic coating layers in a wide range of frequencies (2.5 kHz–5.5 kHz). The proposed concept of applying achromatic coating layers along with the TO-based design method is expected to provide remarkable versatility to design GRIN PC lens-based applications such as energy harvesting, acoustic imaging, and acoustic wireless power transfer in broadband operation.
Two-dimensional electron gas at wurtzite–zinc-blende InP interfaces induced by modulation doping
Authors: Geijselaers Irene , Lehmann Sebastian , Dick Kimberly A. , Pistol Mats-Erik
Published: June 2020

The quality, such as long-range correlation and mobility, of a two-dimensional electron gas (2DEG) is limited by, among other factors, interface roughness, which is inherent to the use of compositional heterostructures. Polytypic heterostructures have atomically sharp interfaces and minimal strain, decreasing the interface roughness, which may increase the mobility and long-range correlation of 2DEGs. In this work, we show the formation of a 2DEG at the wurtzite–zinc blende interface in partially n-type-doped InP nanowires using power-dependent photoluminescence. We additionally determined the wurtzite–zinc blende InP valence band offset to be 35 meV <ΔEv< 70 meV. Our results may enable the study of electron gases at interfaces, which are atomically flat over large areas.
Sequential multiscale model to study crack tip behavior in bi-crystalline graphene
Authors: Verma Prince Kumar , Parashar Avinash
Published: June 2020

The aim of this research article is to develop a sequential multiscale model to study the inter-granular fracture behavior in bi-crystalline graphene. A multiscale model encompasses the microscale behavior at a macroscale level. A sequential multiscale model was developed by defining the traction separation law (TSL), using atomistic simulations, which was later on used to quantify damage in cohesive zone elements in continuum based finite element based simulations. Sequential multiscale models constitute developing bi-crystalline graphene configuration in the environment of molecular dynamics and capture the intergranular crack propagation in graphene. In the molecular dynamics based simulations, symmetrical and asymmetrical tilt grain boundaries were generated in conjunction with edge crack. The TSL derived from these simulations helps in improving the accuracy of continuum level models for predicting intergranular fracture. Spatial stress distribution in the vicinity of the crack tip as well as stress values were captured and compared for atomistic levels with a continuum level for the validation of sequential multiscale models.
Orthorhombic alloys of Ga2O3 and Al2O3
Authors: Seacat Sierra , Lyons John L. , Peelaers Hartwin
Published: June 2020

Ga 2 O 3 has attracted significant attention as a wide-bandgap material for electronic applications. The orthorhombic κ phase is of interest due to its large predicted spontaneous electrical polarization. Here, we use density functional theory and hybrid functionals to investigate how alloying Ga2O3 with Al2O3 can be used to modify lattice constants, bandgaps, and conduction-band offsets. We find that increasing the Al content decreases lattice constants linearly, but that the increase in bandgaps and conduction-band offsets is non-linear, with a bowing of 1.41 eV. Structurally, there is a strong energetic preference of Al atoms to occupy octahedrally coordinated sites, and of Ga atoms to occupy tetrahedral sites. Ga will also occupy pentahedral sites, but at a small energy cost. The formation enthalpy of alloys is smaller than that of the pure materials, with ordered alloys with 50% Al having especially low formation enthalpies. These quantitative results can be used to guide experimental device design.
Principles of long-term fluids handling in paper-based wearables with capillary–evaporative transport
Authors: Shay Timothy , Saha Tamoghna , Dickey Michael D. , Velev Orlin D.
Published: June 2020

We construct and investigate paper-based microfluidic devices, which model long-term fluid harvesting, transport, sensing, and analysis in new wearables for sweat analysis. Such devices can continuously wick fluid mimicking sweat and dispose of it on evaporation pads. We characterize and analyze how the action of capillarity and evaporation can cooperatively be used to transport and process sweat mimics containing dissolved salts and model analytes. The results point out that non-invasive osmotic extraction combined with paper microfluidics and evaporative disposal can enable sweat collection and monitoring for durations longer than 10 days. We model the fluid flow in the new capillary–evaporative devices and identify the parameters enabling their long-term operation. We show that the transport rates are sufficiently large to handle natural sweat rates, while we envision that such handling can be interfaced with osmotic harvesting of sweat, a concept that we demonstrated recently. Finally, we illustrate that the salt film deposited at the evaporation pad would eventually lead to cessation of the process but at the same time will preserve a record of analytes that may be used for long-term biomarker monitoring in sweat. These principles can be implemented in future platforms for wearable skin-interfacing assays or electronic biomarker monitors.
Data-adaptive harmonic analysis of oceanic waves and turbulent flows
Authors: Kondrashov D. , Ryzhov E. A. , Berloff P.
Published: June 2020

We introduce new features of data-adaptive harmonic decomposition (DAHD) that are showcased to characterize spatiotemporal variability in high-dimensional datasets of complex and mutsicale oceanic flows, offering new perspectives and novel insights. First, we present a didactic example with synthetic data for identification of coherent oceanic waves embedded in high amplitude noise. Then, DAHD is applied to analyze turbulent oceanic flows simulated by the Regional Oceanic Modeling System and an eddy-resolving three-layer quasigeostrophic ocean model, where resulting spectra exhibit a thin line capturing nearly all the energy at a given temporal frequency and showing well-defined scaling behavior across frequencies. DAHD thus permits sparse representation of complex, multiscale, and chaotic dynamics by a relatively few data-inferred spatial patterns evolving with simple temporal dynamics, namely, oscillating harmonically in time at a given single frequency. The detection of this low-rank behavior is facilitated by an eigendecomposition of the Hermitian cross-spectral matrix and resulting eigenvectors that represent an orthonormal set of global spatiotemporal modes associated with a specific temporal frequency, which in turn allows to rank these modes by their captured energy and across frequencies, and allow accurate space-time reconstruction. Furthermore, by using a correlogram estimator of the Hermitian cross-spectral density matrix, DAHD is both closely related and distinctly different from the spectral proper orthogonal decomposition that relies on Welch’s periodogram as its estimator method.
Effect of multiaxial stress in thin films on the ferromagnetic resonance mode characteristics
Authors: Layadi A.
Published: June 2020

The effects of multiaxial stress-induced anisotropy on the ferromagnetic resonance modes have been investigated. Equivalent stress quantities (σ1, σ2) are introduced. σ1 and σ2 induce out-of-plane and in-plane magnetic anisotropies, respectively; the corresponding anisotropy fields Hσ1 and Hσ2 are defined. Analytical expressions are derived for the resonance relations, the frequency (Δf) and field (ΔH) linewidths, the imaginary part of magnetic susceptibility (χ′′), and mode intensities (IH and If) for different configurations of the applied magnetic field and magnetization. Saturated and unsaturated states have been considered. Interesting features are observed for the multiaxial stress case and compared to the uniaxial stress one. The differences between the two cases are highlighted. It will be shown how these mode characteristics can be used to detect and measure the multiaxial stress in thin films.
Isotope effects on the high pressure viscosity of liquid water measured by differential dynamic microscopy
Authors: Frost Mungo , Glenzer Siegfried H.
Published: June 2020

Differential dynamic microscopy is performed in diamond anvil cells to measure the viscosity of water along the 24 °C isotherm to high pressure by the determination of the tracer diffusion coefficient of monodisperse silica spheres of known diameter and the application of the Stokes–Einstein–Sutherland equation. This technique allows liquid samples to be compressed to greater pressure prior to freezing than with other viscometry methods. The highest-pressure measurement was made at 1.67 GPa, considerably deeper into the supercompressed regime than previously reported. The effect of the isotopic composition is investigated with samples of normal water, heavy water, and partially deuterated water. When data below 0.25 GPa are excluded, a free volume model fits the observed viscosities well, yielding a theoretical glass transition density close to that observed in very-high-density amorphous ice. The improved fit above 0.25 GPa coincides with the loss of other anomalous behaviors in liquid water caused by hydrogen bonding and represents a transition to properties closer to those of a simple liquid.
Unwelcome guests: a selective history of weed introductions to arid and semi-arid Australia
Authors: Friedel M. H.
Published: June 2020

Following European settlement of Australia, numerous plant species were deliberately introduced for use in crops, pastures, gardens and horticulture, and others arrived by chance. Many subsequently escaped and became weedy. Of the 54 weed species of natural environments of arid and semi-arid Australia that are considered here, 27 were apparently accidentally introduced, 20 were intentionally introduced and 7 were probably introduced both accidentally and intentionally. Livestock including camels and their harness, and contaminated seed and hay were the most common vectors for accidental introduction. Amongst intentional introductions, rather more ornamental species appear to have invaded successfully than pasture species, but the former generally occupy niche habitats. Recent new introductions are few due to pre-border, border and post-border protections, but many current arid zone weeds continue to spread. Understanding the history of weed invasions can help to guide current and future management by clarifying pathways for introduction.
A genome-wide association study of hexanal content related to soymilk off-flavours in seed of soybean (Glycine max)
Authors: Wang Zhikun , Bao Gege , Yang Chao , Yang Mingming , Zhao Xue , Shao Yupeng , Wang Yuanzhuo , Huang Jinxiu , Xia Ning , Han Yingpeng
Published: June 2020

Flavour is an essential quality characteristic of soymilk; however, it contains volatile compounds unacceptable to consumers. Hexanal is the most important flavour compound that gives a sensory beany, grassy flavour in the soymilk. An effective way to reduce hexanal content in soymilk is to screen for and utilise cultivars of soybean (Glycine max (L.) Merr.) with lower hexanal content. The objective of the present study was to dissect the genetic basis of hexanal content in soybean seed by using genome-wide association analysis (GWAS), thereby providing guidance for the selection and breeding of soybean varieties with low hexanal content. We used 24651 single-nucleotide polymorphisms (SNPs) and screened seeds from 111 cultivated soybean accessions to identify quantitative trait nucleotides (QTNs) affecting hexanal content. We discovered 14 novel QTNs located on five different chromosomes that are significantly associated with hexanal content in soybean seed. Among these, 11 QTNs co-localised with quantitative trait loci previously found in linkage or association mapping studies related to protein, oil and/or fatty acid content in soybean seed. We also identified some candidate genes involved in amino acid metabolism, protein content, lipid metabolism and hormone metabolism. Six cultivars with low hexanal content were identified by screening. This is the first GWAS study on hexanal content in soybean seed, and a number of QTNs and candidate genes were identified. Some of these may be useful to breeders for the improvement of marker-assisted breeding efficiency for low hexanal content and may be useful for exploring possible molecular mechanisms underlying hexanal content in soybean seed.
Very-long-chain fatty acids (VLCFAs) in plant response to stress
Authors: Zhukov Anatoly V. , Shumskaya Maria
Published: June 2020

Plant growth is affected by various stresses leading to changes in metabolism. Stress conditions include a variety of biotic and abiotic factors such as pathogens, drought, high and low temperatures and heavy metals. Among multiple physiological responses to stress, there is an adaptive modification in membrane lipid constituents. In particular, the composition of membrane very-long-chain fatty acids (VLCFAs) changes both qualitatively and quantitatively. Here, we evaluate the current data on the effects of stress on plant VLCFAs composition. In summary, some stress conditions lead to an increase of the total amount of saturated and, in certain cases, unsaturated VLCFAs. Currently, it is not completely clear how these molecules participate in the biology of plant cell membranes. Their possible functional roles are discussed.
Energy storage emerging: A perspective from the Joint Center for Energy Storage Research
Authors: Trahey Lynn , Brushett Fikile R. , Balsara Nitash P. , Ceder Gerbrand , Cheng Lei , Chiang Yet-Ming , Hahn Nathan T. , Ingram Brian J. , Minteer Shelley D. , Moore Jeffrey S. , Mueller Karl T. , Nazar Linda F. , Persson Kristin A. , Siegel Donald J. , Xu Kang , Zavadil Kevin R. , Srinivasan Venkat , Crabtree George W.
Published: June 2020

Energy storage is an integral part of modern society. A contemporary example is the lithium (Li)-ion battery, which enabled the launch of the personal electronics revolution in 1991 and the first commercial electric vehicles in 2010. Most recently, Li-ion batteries have expanded into the electricity grid to firm variable renewable generation, increasing the efficiency and effectiveness of transmission and distribution. Important applications continue to emerge including decarbonization of heavy-duty vehicles, rail, maritime shipping, and aviation and the growth of renewable electricity and storage on the grid. This perspective compares energy storage needs and priorities in 2010 with those now and those emerging over the next few decades. The diversity of demands for energy storage requires a diversity of purpose-built batteries designed to meet disparate applications. Advances in the frontier of battery research to achieve transformative performance spanning energy and power density, capacity, charge/discharge times, cost, lifetime, and safety are highlighted, along with strategic research refinements made by the Joint Center for Energy Storage Research (JCESR) and the broader community to accommodate the changing storage needs and priorities. Innovative experimental tools with higher spatial and temporal resolution, in situ and operando characterization, first-principles simulation, high throughput computation, machine learning, and artificial intelligence work collectively to reveal the origins of the electrochemical phenomena that enable new means of energy storage. This knowledge allows a constructionist approach to materials, chemistries, and architectures, where each atom or molecule plays a prescribed role in realizing batteries with unique performance profiles suitable for emergent demands.
Cotranslational folding cooperativity of contiguous domains of α-spectrin
Authors: Kemp Grant , Nilsson Ola B. , Tian Pengfei , Best Robert B. , von Heijne Gunnar
Published: June 2020

Significance

In living cells, proteins are produced in a sequential way by ribosomes. This vectorial process allows the growing protein chain to start to fold before translation has been completed. Thereby, cotranslational protein folding can be significantly different than the folding of a full-length protein in isolation. Here, we show how structurally similar repeat domains, normally produced as parts of a single long polypeptide, affect the cotranslational folding of their neighbors. This provides insight into how the cell may efficiently produce multidomain proteins, paving the way for future studies in vivo or with chaperones. We also provide an estimated magnitude of the mechanical force on the nascent chain generated by cotranslational folding, calculated from biochemical measurements and molecular dynamics simulations.
Stabilization of extensive fine-scale diversity by ecologically driven spatiotemporal chaos
Authors: Pearce Michael T. , Agarwala Atish , Fisher Daniel S.
Published: June 2020

Significance

The diversity of living organisms is a fundamental feature of biology, yet still challenging to understand. Genomic data reveal that many closely related strains of bacteria can coexist for far longer than expected from “survival of the fittest.” To explain this, is it necessary to assume a multitude of specialist niches, or are other mechanisms possible? We investigate, from simple but general models, an alternate scenario: coexistence of a large number of closely related strains in a chaotic state driven by ecological interactions. The chaos is characterized by local blooms and busts that are out of sync at different spatial locations. A natural example is multiple nonspecialist strains of a pathogen species infecting multiple strains of a host species.
Functional ultrasound imaging of deep visual cortex in awake nonhuman primates
Authors: Blaize Kévin , Arcizet Fabrice , Gesnik Marc , Ahnine Harry , Ferrari Ulisse , Deffieux Thomas , Pouget Pierre , Chavane Frédéric , Fink Mathias , Sahel José-Alain , Tanter Mickael , Picaud Serge
Published: June 2020

Deep regions of the brain are not easily accessible to investigation at the mesoscale level in awake animals or humans. We have recently developed a functional ultrasound (fUS) technique that enables imaging hemodynamic responses to visual tasks. Using fUS imaging on two awake nonhuman primates performing a passive fixation task, we constructed retinotopic maps at depth in the visual cortex (V1, V2, and V3) in the calcarine and lunate sulci. The maps could be acquired in a single-hour session with relatively few presentations of the stimuli. The spatial resolution of the technology is illustrated by mapping patterns similar to ocular dominance (OD) columns within superficial and deep layers of the primary visual cortex. These acquisitions using fUS suggested that OD selectivity is mostly present in layer IV but with extensions into layers II/III and V. This imaging technology provides a new mesoscale approach to the mapping of brain activity at high spatiotemporal resolution in awake subjects within the whole depth of the cortex.
The appearance and duration of the Jehol Biota: Constraint from SIMS U-Pb zircon dating for the Huajiying Formation in northern China
Authors: Yang Saihong , He Huaiyu , Jin Fan , Zhang Fucheng , Wu Yuanbao , Yu Zhiqiang , Li Qiuli , Wang Min , O'Connor Jingmai K. , Deng Chenglong , Zhu Rixiang , Zhou Zhonghe
Published: June 2020

The Lower Cretaceous Huajiying Formation of the Sichakou Basin in northern Hebei Province, northern China contains key vertebrate taxa of the early Jehol Biota, e.g.,Protopteryx fengningensis,Archaeornithura meemannae,Peipiaosteus fengningensis, andEoconfuciusornis zhengi. This formation arguably documents the second-oldest bird-bearing horizon, producing the oldest fossil records of the two major Mesozoic avian groups Enantiornithes and Ornithuromorpha. Hence, precisely determining the depositional ages of the Huajiying Formation would advance our understanding of the evolutionary history of the Jehol Biota. Here we present secondary ion mass spectrometry (SIMS) U-Pb zircon analysis results of eight interbedded tuff/tuffaceous sandstone samples from the Huajiying Formation. Our findings, combined with previous radiometric dates, suggest that the oldest enantiornithine and ornithuromorph birds in the Jehol Biota are ∼129−131 Ma, and that the Jehol Biota most likely first appeared at ∼135 Ma. This expands the biota’s temporal distribution from late Valanginian to middle Aptian with a time span of about 15 My.
Topoisomerase I-driven repair of UV-induced damage in NER-deficient cells
Authors: Saha Liton Kumar , Wakasugi Mitsuo , Akter Salma , Prasad Rajendra , Wilson Samuel H. , Shimizu Naoto , Sasanuma Hiroyuki , Huang Shar-yin Naomi , Agama Keli , Pommier Yves , Matsunaga Tsukasa , Hirota Kouji , Iwai Shigenori , Nakazawa Yuka , Ogi Tomoo , Takeda Shunichi
Published: June 2020

Significance

NER removes helix-destabilizing bulky adducts including UV lesions and crosslinks generated by formaldehyde. NER protects skin cells from carcinogenesis. XP patients deficient in NER develop progressive neurological dysfunction. We discovered that collaboration between TOP1 and the BER pathway can substitute for the lack of NER. This previously unappreciated repair pathway is initiated by TOP1-dependent sensing topological alterations near UV lesions and subsequent SSB formation followed by BER. Considering that the SSB formation by TOP1 is the rate-limiting step, and TOP1 expression is very low in the skin and neuronal tissues, our finding may help understand the molecular mechanisms and genetic determinants underlying the neurological dysfunction of XP patients, although TOP1-relevant endogenous lesions are currently unknown.
Cerebral amyloid angiopathy-linked β-amyloid mutations promote cerebral fibrin deposits via increased binding affinity for fibrinogen
Authors: Cajamarca Steven A. , Norris Erin H. , van der Weerd Louise , Strickland Sidney , Ahn Hyung Jin
Published: June 2020

Significance

We found an increased interaction between CAA-linked mutant Aβ and fibrin(ogen) that may not only result in severely altered fibrin structure and function but may also lead to vast amounts of fibrin(ogen)/Aβ codeposition, as well as fibrin deposits in HCAA patients. This finding provides a molecular mechanism for how CAA-linked mutations may lead to severe cerebrovascular pathology in HCAA patients by enhancing the protein–protein interaction.
PEBP1 acts as a rheostat between prosurvival autophagy and ferroptotic death in asthmatic epithelial cells
Authors: Zhao Jinming , Dar Haider H. , Deng Yanhan , St. Croix Claudette M. , Li Zhipeng , Minami Yoshinori , Shrivastava Indira H. , Tyurina Yulia Y. , Etling Emily , Rosenbaum Joel C. , Nagasaki Tadao , Trudeau John B. , Watkins Simon C. , Bahar Ivet , Bayır Hülya , VanDemark Andy P. , Kagan Valerian E. , Wenzel Sally E.
Published: June 2020

Significance

Our work identifies regulatory mechanisms between ferroptosis and autophagy. We discovered that PE-binding protein-1 (PEBP1) is pivotal for dynamic interactions between the ferroptotic cell death program and prosurvival autophagy in asthmatic/Type 2 stimulated airway epithelial cells and that concurrent activation of autophagy protects cells from ferroptotic death and mitochondrial DNA release. Similar findings are observed in Type 2 Hi asthmatic epithelial cells where high 15-lipoxygenase-1 (15LO1)–PEBP1 and light chain-3 II (LC3-II) levels associate with low bronchoalveolar lavage fluid mitochondrial DNA and severe disease. Our findings of concomitant activation of ferroptosis and autophagy by 15LO1–PEBP1 complexes and their hydroperoxy-phospholipids reveal a pathobiologic pathway relevant to asthma and amenable to therapeutic targeting.