bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional Strategies and Life Histories of Grasses Underlying Yield and Resilience
Authors: Crowley Sharon , Wingler Astrid
Published: February 2020

The family of Poaceae (grasses) includes many economically important crops. While grass grain crops (cereals) are typically annual, bioenergy and forage crops can have annual or perennial life histories. Annuals and perennials differ in important life history traits, such as the regulation of flowering and senescence, which determine to what extent resources are allocated to the grain, vegetative growth, or storage. These differences are also reflected in physiological characteristics; in particular, leaf traits that can be used to determine functional strategies (competitive, stress tolerant, or ruderal). While ruderality is associated with yield in annual grain crops, stress tolerance is usually higher in perennials. In this article, we discuss variation in functional strategies within perennial ryegrass grass (
Lolium perenne
) and species of the genus
Brachypodium
, demonstrating variation in characteristics for ruderality and stress tolerance. We argue that regulation of senescence of organs and whole plants determines these strategies and propose ideas on how functional strategies could potentially be optimised to increase grain yield in perennial grasses while maintaining stress resilience and other beneficial traits associated with perenniality.
Multi‐Omics Insights into the Evolution of Angiosperm Resurrection Plants
Authors: Lyall Rafe , Gechev Tsanko
Published: February 2020

A small group of angiosperms possess vegetative desiccation tolerance (VDT). This unique ability allows them to withstand near total loss of cellular water and recover unharmed upon rehydration. Recently, omics technologies have begun to give greater insight into the mechanisms that regulate VDT. Several angiosperm resurrection plant genomes, from both monocot and eudicot lineages, have been sequenced in the past decade. Multiple transcriptomic and metabolomic analyses of desiccation and rehydration in resurrection plants have emphasised the importance and ubiquity of known VDT responses, such as the induction of late embryogenesis abundants (LEAs), sugars, and antioxidants. These studies have also confirmed the similarity between VDT and the process of orthodox seed maturation drying, and highlighted the connection between embryonic, seedling, and vegetative DT. However, the exact genes and pathways that regulate the acquisition of seed traits in leaves remain elusive. This article attempts to integrate what is currently understood about the evolution and regulation of VDT in angiosperm resurrection plants, drawing from the rapidly growing collection of omics datasets derived from these species. The limits of current knowledge, future research perspectives, and the utility of VDT research as a resource for the improvement of drought tolerance in crop species are also discussed.
Progress on Light‐Emitting Electrochemical Cells toward Blue Emission, High Efficiency, and Long Lifetime
Authors: Zhang Chen , Liu Ruihuan , Zhang Dongdong , Duan Lian
Published: February 2020

Since their emergence in the 1990s, light‐emitting electrochemical cells (LECs) have attracted much attention due to their unique properties and potential for use as an alternative technology for illuminations and displays. After decades of development, however, the performance of LECs remains far from satisfactory for practical applications, in particular for those requiring blue light. Efforts have been made to develop of highly efficient blue‐emitting materials and more advanced device structures, aiming at realizing blueshifted emission, enhancing efficiency, and extending prolonged device lifetimes. A timely review into the current state of blue LECs is deemed imperative, as a full understanding of the molecular and device design strategy and identification of the major challenges that must be addressed to realize practical applications is necessary. A specific summary of recent progress on blue LECs is provided, with the focus placed on design strategies for blue emitters for LECs and device structures with respect to color tuning, efficiency enhancement, and stability improvement. Finally, the direction of development strategies in the future is suggested.
Air‐Stable Highly Crystalline Formamidinium Perovskite 1D Structures for Ultrasensitive Photodetectors
Authors: Chen Gaosong , Qiu Yuchen , Gao Hanfei , Zhao Yingjie , Feng Jiangang , Jiang Lei , Wu Yuchen
Published: February 2020

State‐of‐the‐art optoelectronic devices based on metal‐halide perovskites demand solution‐processed structures with high crystallinity, controlled crystallographic orientation, and enhanced environmental stability. Formamidinium lead iodide (α‐FAPbI3) possesses a suitable bandgap of 1.48 eV and enhanced thermal stability, whereas perovskite‐type polymorph (α‐phase) is thermodynamically instable at ambient temperatures. Stable α‐FAPbI3 perovskite 1D structure arrays with high crystallinity and ordered crystallographic orientation are developed by controlled nucleation and growth in capillary bridges. By surface functionalization with phenylethylammonium ions (PEA+), FAPbI3 wires sustain a stable α‐phase after 28 day storage in the ambient environment with a relative humidity of 50%. Enhanced photoluminescence (PL) intensity and elongated PL lifetime demonstrate suppressed trap density and high crystallinity in these 1D structures, which is also reflected by the enhanced diffraction density and pure (001) crystallographic orientation in the grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) pattern. Based on these high‐quality 1D structures, sensitive photodetectors are achieved with average responsivities of 5282 A W−1, average specific detectivities of more than 1.45 × 1014 Jones, and a fast response speed with a 3 dB bandwidth of 15 kHz.
Camouflaging Nanoparticles with Brain Metastatic Tumor Cell Membranes: A New Strategy to Traverse Blood–Brain Barrier for Imaging and Therapy of Brain Tumors
Authors: Wang Caixia , Wu Bo , Wu Yuting , Song Xinyue , Zhang Shusheng , Liu Zhihong
Published: February 2020

Glioblastoma multiforme is one of the most fatal intracranial tumors with no effective treatment. The drug concentration in tumor sites is usually insufficient to reach therapeutic levels, due to poor blood–brain‐barrier (BBB) permeability and short biological half‐life. Inspired by the proneness of those malignant tumors to brain metastasis, a brain metastatic tumor cell membrane‐coated nanocarrier with core–shell structure is constructed to cross BBB for imaging and photothermal therapy of early brain tumors. The cell membranes as the shell are extracted from different metastatic tumor cells, which endow the nanoparticles with BBB‐crossing ability and long circulation. Indocyanine green (ICG)‐loaded polymeric nanoparticle as the core allows fluorescence imaging and phototherapy of brain tumors. The as‐prepared biomimetic nanoparticles display superb BBB penetration and effective suppression of tumor growth. These findings suggest the biomimetic nanotechnology provides a new insight for the design of BBB‐crossing nanomaterials and is promising to treat brain diseases.
Kirigami‐Inspired Self‐Assembly of 3D Structures
Authors: Abdullah Arif M. , Li Xiuling , Braun Paul V. , Rogers John A. , Hsia K. Jimmy
Published: February 2020

Self‐assembly of 3D structures presents an attractive and scalable route to realize reconfigurable and functionally capable mesoscale devices without human intervention. A common approach for achieving this is to utilize stimuli‐responsive folding of hinged structures, which requires the integration of different materials and/or geometric arrangements along the hinges. It is demonstrated that the inclusion of Kirigami cuts in planar, hingeless bilayer thin sheets can be used to produce complex 3D shapes in an on‐demand manner. Nonlinear finite element models are developed to elucidate the mechanics of shape morphing in bilayer thin sheets and verify the predictions through swelling experiments of planar, millimeter‐scaled PDMS (polydimethylsiloxane) bilayers in organic solvents. Building upon the mechanistic understandings, The transformation of Kirigami‐cut simple bilayers into 3D shapes such as letters from the Roman alphabet (to make “ADVANCED FUNCTIONAL MATERIALS”) and open/closed polyhedral architectures is experimentally demonstrated. A possible application of the bilayers as tether‐less optical metamaterials with dynamically tunable light transmission and reflection behaviors is also shown. As the proposed mechanistic design principles could be applied to a variety of materials, this research broadly contributes toward the development of smart, tetherless, and reconfigurable multifunctional systems.
Polyphenol‐Sensitized Atomic Layer Deposition for Membrane Interface Hydrophilization
Authors: Yang Xiaobin , Sun Pan , Zhang Huiru , Xia Zijing , Waldman Ruben Z. , Mane Anil U. , Elam Jeffrey W. , Shao Lu , Darling Seth B.
Published: February 2020

Improvements in energy–water systems will necessitate fabrication of high‐performance separation membranes. To this end, interface engineering is a powerful tool for tailoring properties, and atomic layer deposition (ALD) has recently emerged as a promising and versatile approach. However, most non‐polar polymeric membranes are not amenable to ALD processing due to the absence of nucleation sites. Here, a sensitization strategy for ALD‐coating is presented, illustrated by membrane interface hydrophilization. Facile dip‐coating with polyphenols effectively sensitizes hydrophobic polymer membranes to TiO2 ALD coating. Tannic acid‐sensitized ALD‐coated membranes exhibit outstanding underwater crude oil repulsion and rigorous mechanical stability through bending and rinsing tests. As a result, these membranes demonstrate outstanding crude oil‐in‐water separation and reusability compared to untreated membranes or those treated with ALD without polyphenol pretreatment. A possible polyphenol‐sensitized ALD mechanism is proposed involving initial island nucleation followed by film intergrowth. This polyphenol sensitization strategy enriches the functionalization toolbox in material science, interface engineering, and environmental science.
Functional Coatings on High‐Performance Polymer Fibers for Smart Sensing
Authors: Galinski Henning , Leutenegger Daniel , Amberg Martin , Krogh Fabio , Schnabel Volker , Heuberger Manfred , Spolenak Ralph , Hegemann Dirk
Published: February 2020

Above a critical temperature, high‐performance fibers may lose their mechanical properties resulting in catastrophic events of damage when, e.g., used as load‐carrying ropes. Here, a method to functionalize polymer fibers with thermochromic optical coatings that enable signaling of damaging thermal history is introduced. These smart coatings are comprised of an index‐tunable anti‐reflection coating based on chalcogenide phase change materials (PCM). It is demonstrated that the insulator−metal phase transition of these materials can be aligned with the critical deterioration temperature of both polyethylene terephthalate (PET) monofilaments and liquid‐crystal polyester (LCP) yarns by composition tuning. The carefully designed optical system amplifies the change in optical properties of its constituents upon phase change. The thermal and mechanical degradation of these fibers can thus be monitored and displayed by eye.
Tip‐Induced Inversion of the Chirality of a Molecule's Adsorption Potential Probed by the Switching Directionality
Authors: Bauer Anja , Maier Markus , Schosser Werner M. , Diegel Josefine , Paschke Fabian , Dedkov Yuriy , Pauly Fabian , Winter Rainer F. , Fonin Mikhail
Published: February 2020

The switching behavior of surface‐supported molecular units excited by current, light, or mechanical forces is determined by the shape of the adsorption potential. The ability to tailor the energy landscape in which a molecule resides at a surface gives the possibility of imposing a desired response, which is of paramount importance for the realization of molecular electronic units. Here, by means of scanning tunneling microscopy, a triazatruxene (TAT) molecule on Ag(111) is studied, which shows a switching behavior characterized by transitions of the molecule between three states, and which is attributed to three energetically degenerate bonding configurations. Upon tunneling current injection, the system can be excited and continuously driven, showing a switching directionality close to 100%. Two surface enantiomers of TAT show opposite switching directions pointing at the chirality of the energy landscape of the adsorption potential as a key ingredient for directional switching. Further, it is shown that by tuning the tunneling parameters, the symmetry of the adsorption potential can be controllably adjusted, leading to a suppression of the directionality or an inversion of the switching direction. The findings represent a molecule‐surface model system exhibiting unprecedented control of the shape of its adsorption potential.
Electrical Characterization of Individual Cesium Lead Halide Perovskite Nanowires Using Conductive AFM
Authors: Stern Avigail , Aharon Sigalit , Binyamin Tal , Karmi Abeer , Rotem Dvir , Etgar Lioz , Porath Danny
Published: February 2020

Perovskite nanostructures have attracted much attention in recent years due to their suitability for a variety of applications such as photovoltaics, light‐emitting diodes (LEDs), nanometer‐size lasing, and more. These uses rely on the conductive properties of these nanostructures. However, electrical characterization of individual, thin perovskite nanowires has not yet been reported. Here, conductive atomic force microscopy characterization of individual cesium lead halide nanowires is presented. Clear differences are observed in the conductivity of nanowires containing only bromide and nanowires containing a mixture of bromide and iodide. The differences are attributed to a higher density of crystalline defects, deeper trap states, and higher inherent conductivity for nanowires with mixed bromide–iodide content.
High‐Resolution Patterned Biobased Thin Films via Self‐Assembled Carbohydrate Block Copolymers and Nanocellulose
Authors: Gestranius Marie , Otsuka Issei , Halila Sami , Hermida‐Merino Daniel , Solano Eduardo , Borsali Redouane , Tammelin Tekla
Published: February 2020

The exploitation of the effortless self‐assembly behavior of biomass‐based bricks can be seen as a promising route toward the innovative architectures. Here, a straightforward approach is presented where carbohydrate‐based diblock copolymer, polystyrene‐block‐maltoheptaose (PS‐b‐MH), is organized either on a rigid ultrathin film or on a flexible self‐standing film of wood‐derived cellulose nanofibrils (CNFs). During solvent annealing PS‐b‐MH deposited on relatively rough CNF film undergoes spontaneous rearrangement into high‐resolution patterns with a diblock domain spacing of 10–15 nm. The ideal conditions the self‐assembly require weak interactions between block copolymer and the substrate to increase the chain mobility and enable rearrangements. This is exactly how the system behaves. Adsorption studies of PS‐b‐MH on CNF surfaces reveal weak interactions, and the formed PS‐b‐MH layer is soft and mobile. Even the appearance of more challenging vertical orientation formed on smooth CNF substrates is tentatively evidenced by grazing‐incidence small‐angle X‐ray scattering and atomic force microscope indicating favorable surface interactions between CNF and PS‐b‐MH.
Nonclassical Block Copolymer Self‐Assembly Resulting from a Constrained Location of Chains and Junctions
Authors: Matsushita Yushu , Takano Atsushi , Vayer Marylène , Sinturel Christophe
Published: February 2020

During the self‐assembly process of block copolymers, interfaces are formed as a result of the microphase separation between the blocks. The location of the polymer chains and block junctions with respect to these interfaces is crucial and drives the morphology. It depends on the dispersities (e.g., molecular mass and composition) of the blocks, their architectures (e.g., linear vs star), and the type of interaction (e.g., repulsion vs attraction). In this review, the authors focus on the formation of unusual morphologies that are obtained in the following three categories: i) multimodal blends of block polymers, ii) star block polymers, and iii) supramolecular assemblies composed of block copolymers. Although these three examples seem to be very different from one another, the authors demonstrate in this review that they all share a constrained location of their chains and/or junctions with respect to the interfaces. In this sense, they deviate from the common behavior of simple linear block copolymers, in which the junctions are located on the interface and homogeneously distributed onto it.
Stretchable Sensors for Nanomolar Glucose Detection
Authors: Imamura Amanda , Zakashansky Julia , Cho Kenny , Lin Lancy , Carrilho Emanuel , Khine Michelle
Published: February 2020

Biosensors that detect analytes in sweat face the challenge of maintaining sensitivity upon miniaturization. Various materials and processes have been developed to create nanostructured electrodes with high surface areas to mitigate this issue. The need remains, however, for biocompatible materials that can be scalably integrated into wearable devices. This paper details a gold thin‐film electrode fabricated using a thermoplastic shape memory polymer to create hierarchical wrinkled structures via the miniaturization process, followed by transfer onto a soft, stretchable substrate. The final stretchable electrode, which is ≈30 times smaller than that of the original, unshrunk electrode, retains its original surface area. Even more remarkably, further enhancement in current density is achieved upon stretching the electrode to 210% of its original length; improved sensitivity remains stable after relaxation of the polymer. Stretching aids diffusion limited reactions, such as the reduction and oxidation of [Fe(CN)6]3−/4−. The stretchable electrodes sensitively detect glucose without enzymes or additional labels at physiological pH in the range of 1 × 10−7–1 × 10−4 m with a calculated limit of detection of 2.22 × 10−8 m, among the lowest reported for a flexible, enzyme‐free sensor.
Wearable Electronic Textiles from Nanostructured Piezoelectric Fibers
Authors: Mokhtari Fatemeh , Spinks Geoffrey M. , Fay Cormac , Cheng Zhenxiang , Raad Raad , Xi Jiangtao , Foroughi Javad
Published: February 2020

Wearable energy harvesting is of practical interest for many years and for diverse applications, including development of self‐powered wireless sensors within garments for human health monitoring. Herein, a novel approach is reported to create wearable energy generators and sensors using nanostructured hybrid piezoelectric fibers and exploiting the enormous variety of textile architectures. It is found that high performance hybrid piezofiber is obtained using a barium titanate (BT) nanoparticle and poly(vinylidene fluoride) (PVDF) with a mass ratio of 1:10. These fibers are knitted to form a wearable energy generator that produced a maximum voltage output of 4 V and a power density 87 μW cm−3 which is 45 times higher than earlier reported for piezoelectric textiles. The wearable energy generator charged a 10 μF capacitor in 20 s which is four and six times faster than previously reported for PVDF/BT and PVDF energy generators, respectively. It also emerges that the established knitted energy harvester exhibits sensitivity of 6.3 times higher in compare with the piezofibers energy generator. A knee sleeve prototype based on a PVDF/BT wearable device for monitoring real‐time precise healthcare is demonstrated. The developed processing method is scalable for the fabrication of industrial quantities of smart textiles.
Rapid and Selective NH3 Sensing by Porous CuBr
Authors: Güntner Andreas T. , Wied Markus , Pineau Nicolay J. , Pratsinis Sotiris E.
Published: February 2020

Fast and selective detection of NH3 at parts‐per‐billion (ppb) concentrations with inexpensive and low‐power sensors represents a long‐standing challenge. Here, a room temperature, solid‐state sensor is presented consisting of nanostructured porous (78%) CuBr films. These are prepared by flame‐aerosol deposition of CuO onto sensor substrates followed by dry reduction and bromination. Each step is monitored in situ through the film resistance affording excellent process control. Such porous CuBr films feature an order of magnitude higher NH3 sensitivity and five times faster response times than conventional denser CuBr films. That way, rapid (within 2.2 min) sensing of even the lowest (e.g., 5 ppb) NH3 concentrations at 90% relative humidity is attained with outstanding selectivity (30–260) over typical confounders including ethanol, acetone, H2, CH4, isoprene, acetic acid, formaldehyde, methanol, and CO, superior to state‐of‐the‐art sensors. This sensor is ideal for hand‐held and battery‐driven devices or integration into wearable electronics as it does not require heating. From a broader perspective, the process opens exciting new avenues to also explore other bromides and classes of semiconductors (e.g., sulfides, nitrides, carbides) currently not accessible by flame‐aerosol technology.
Incorporating Beliefs and Experiences into Choice Experiment Analysis: Implications for Policy Recommendations
Authors: Dissanayake Sahan T. M. , Meyer Andrew G.
Published: February 2020

We show that respondents' beliefs about future outcomes and prior recreational experiences affect policy recommendations from choice experiments. For New England residents, we find that willingness to pay for a new national park in Maine differs based on respondents' stated beliefs about the status quo long‐term land use. We also find that respondents who do (do not) hunt or snowmobile would pay significantly more (less) for a park allowing these activities. Land managers may find a two‐park solution (one allowing the activities and one prohibiting them) would be best; this insight would be missed when neglecting to model conflicting recreational preferences.
Lowland rice yield and profit response to fertilizer application in Rwanda
Authors: Nabahungu Nsharwasi Léon , Cyamweshi Athanase R. , Kayumba John , Kokou Kintché , Mukuralinda Athanase , Cirhuza Jackson M. , Wortmann Charles S.
Published: February 2020

Rice (Oryza sativa) production in Rwanda increased by 70% while yield ha−1 decreased during the past decade. Yield has biotic and abiotic constraints including inadequate nutrient supply. Yield response functions for N, P, and K were determined in eight marshlands grouped into four clusters. Additional treatment allowed for the diagnosis of response to Mg–S–Zn–B (MgSZnB). Rice grain yield with no fertilizer applied was 2.27 Mg ha−1. Mean yield increases were 2.35, 1.53, and 1.71 Mg ha−1 with N, P, and K application, respectively. The mean economically optimal rates (EOR) were 58 to >150, 11–30, and 21–35 kg ha−1 for N, P, and K, respectively, depending on cluster and the cost of fertilizer. Yield responses to nutrient rates were similar across marshland clusters, and a single response function for each of P and K can serve all four clusters, while the response to N differed for Cluster B compared with A, BC, and C. Net returns to applied P and K were greater than for N, but the application of N is likely needed for such responses to P and K. The MgSZnB resulted in a mean grain yield increase of 1.72 Mg ha−1 with increases in all marshlands, but the information was not sufficient to determine which nutrients of MgSZnB were deficient or their optimal application rates. Fertilizer use can be very profitable for rice production in Rwanda. Profit can be enhanced with the application at less than EOR when fertilizer use is financially constrained.
Electrically Controlled Soft Actuators with Multiple and Reprogrammable Actuation Modes
Authors: Wang Yang , Wang Zhijian , He Qiguang , Iyer Prajval , Cai Shengqiang
Published: February 2020

New forms of soft actuators have enabled the construction of novel soft robots with various functionalities. Though previous researches have successfully fabricated soft actuators with diverse actuation modes, their actuation capabilities are often fixed once their fabrication is completed. Herein, an electrically controlled soft actuator with multiple and reprogrammable actuation modes is designed and fabricated. The soft actuator is composed of two layers of disulfide liquid crystal elastomer (ss‐LCE) film with embedded resistive heating wires of serpentine shape. The actuation mode of the actuator can be programmed by introducing a certain alignment of liquid crystal mesogens in the ss‐LCE film, which is achieved by the controlled deformation of the actuator at room temperature and the rearrangement of the polymer network through disulfide exchange reaction in the material. The actuation mode of the actuator can be easily erased by heating it up to 180 °C, and a new mode of actuation can be introduced by deforming the actuator to a new shape at room temperature. With the reprogrammable and multiple actuation modes, a reusable and general‐purpose soft actuator is demonstrated herein which can meet various requirements in constructing new soft active devices.
Environmental variation impacts trait expression and selection in the legume–rhizobium symbiosis
Authors: Batstone Rebecca T. , Peters Madeline A. E. , Simonsen Anna K. , Stinchcombe John R. , Frederickson Megan E.
Published: February 2020

Premise

The ecological outcomes of mutualism are well known to shift across abiotic or biotic environments, but few studies have addressed how different environments impact evolutionary responses, including the intensity of selection on and the expression of genetic variance in key mutualism‐related traits.

Methods

We planted 30 maternal lines of the legume Medicago lupulina in four field common gardens and compared our measures of selection on and genetic variance in nodulation, a key trait reflecting legume investment in the symbiosis, with those from a previous greenhouse experiment using the same 30 M. lupulina lines.

Results

We found that both the mean and genetic variance for nodulation were much greater in the greenhouse than in the field and that the form of selection on nodulation significantly differed across environments. We also found significant genotype‐by‐environment (G × E) effects for fitness‐related traits that were generated by differences in the rank order of plant lines among environments.

Conclusions

Overall, our results suggest that the expression of genotypic variation and selection on nodulation differ across environments. In the field, significant rank‐order changes for plant fitness potentially help maintain genetic variation in natural populations, even in the face of directional or stabilizing selection.
2‐Benzoyl Thienothiazoles from Annulation of C−H Bonds in Acetophenone Oximes
Authors: Pham Phuc H. , Nguyen Khang X. , Nguyen Ninh P. , Pham Hoai T. B. , Nguyen Tung T. , Phan Nam T. S.
Published: February 2020

We report a method for coupling of acetophenone oxime acetates, C−H bonds α to ketones, and elemental sulfur. The reactions proceeded in the presence of Li2CO3 (base) and DMSO (solvent) to afford 2‐benzoyl benzothienothiazoles. Functionalities including halogen, protected alcohol, and heterocycle groups were compatible with reaction conditions. Use of methylene C−H bonds in β‐keto esters is also viable. This marks a rare example for mild synthesis of S‐heterocycles from ketoxime acetates.
Implications of accumulative stress burdens during critical periods of early postnatal life for mortality risk among Guale interred in a colonial era cemetery in Spanish Florida (ca. AD 1605–1680)
Authors: Garland Carey J.
Published: February 2020

Objective

Research situated within the Developmental Origins of Health and Disease demonstrates that stressors are correlated with future mortality risk, especially if experienced frequently and during early periods of postnatal life. This study examines if the developmental timing and frequency of early life stressors influenced mortality risk for Indigenous Guale in Spanish Florida during the 17th century.

Materials and Methods

The present study examines internal enamel microgrowth disruptions (accentuated lines—AL) from Guale individuals (n = 52) interred at Mission Santa Catalina de Guale on St. Catherines Island, Georgia (AD 1605–1680). Teeth were thin‐sectioned and microscopically analyzed to document AL variables as predictors of age‐at‐death.

Results

Individuals with AL died earlier than those without AL. This difference, however, was not significant. Individuals who exhibit AL formed during their first year of life died on average three times earlier than those who did not. The frequency of AL and age‐at‐first‐AL are significantly correlated with age‐at‐death, and Cox hazard analyses indicates that individuals with early forming and frequent AL had increased risks of early death.

Discussion

This study emphasizes how the lived experiences of Guale children shaped demographic patterns during the 17th century. The survival of early life stressors resulted in life history trade‐offs and increased risks for early death. Mortality risks were exacerbated for individuals who experienced frequent stressors during the earliest periods of life. This underscores a role for bioarchaeology in understanding of how accumulative stress burdens during the earliest years of postnatal life may influence mortality risk.
Ultrawideband Spin‐Decoupled Coding Metasurface for Independent Dual‐Channel Wavefront Tailoring
Authors: Guo Wen‐Long , Wang Guang‐Ming , Luo Xin‐Yao , Hou Hai‐Sheng , Chen Ke , Feng Yijun
Published: February 2020

Achieving distinct functionalities for electromagnetic (EM) waves with opposite handedness in a broad frequency range is highly desirable and essential for modern wireless communications and radar stealth. However, available functional meta‐devices still suffer from the issues of locked functionalities or spin‐decoupled properties but with limited bandwidth. Here, a spin‐decoupled coding metasurface is presented for achieving independently spin‐controlled functionalities with high efficiency in an ultrawide frequency band. By synthesizing the Jones matrix, it is predicted that two half‐wave plates with a phase difference of 90° can form a 1‐bit coding metasurface operating for orthogonal spins independently. As proofs of concept, two meta‐devices are implemented by the metasurface in the microwave region. The first meta‐device performs as a spin‐decoupled beam deflector while the second one shows an ability to generate spin‐decoupled multi‐beams carrying desired orbital angular momentums. Both of the designed meta‐devices can operate in the whole band of 7.5–18.5 GHz (with relative bandwidth of 80%), which, to the best knowledge, is so far the broadest bandwidth that can be achieved by spin‐decoupled metasurfaces. This may trigger interest and open opportunities for advanced functional meta‐devices in practical applications, for example, multichannel metasurface antennas, or multifunctional low‐scattering devices in microwave region.
Sulfonium‐Based Homolytic Substitution Observed for the Radical SAM Enzyme HemN
Authors: Ji Wenjuan , Ji Xinjian , Zhang Qi , Mandalapu Dhanaraju , Deng Zixin , Ding Wei , Sun Peng , Zhang Qi
Published: February 2020

Sulfur‐based homolytic substitution (SH reaction) plays an important role in synthetic chemistry, yet whether such a reaction could occur on the positively charged sulfonium compounds remains unknown. In the study of the anaerobic coproporphyrinogen III oxidase HemN, a radical S‐adenosyl‐l‐methionine (SAM) enzyme involved in heme biosynthesis, we observed the production of di‐(5′‐deoxyadenosyl)methylsulfonium, which supports a deoxyadenosyl (dAdo) radical‐mediated SH reaction on the sulfonium center of SAM. The sulfonium‐based SH reactions were then investigated in detail by density functional theory calculations and model reactions, which showed that this type of reactions is thermodynamically favorable and kinetically competent. These findings represent the first report of sulfonium‐based SH reactions, which could be useful in synthetic chemistry. Our study also demonstrates the remarkable catalytic promiscuity of the radical SAM superfamily enzymes.
The Limited Predictive Power of the Pauling Rules
Authors: George Janine , Waroquiers David , Di Stefano Davide , Petretto Guido , Rignanese Gian‐Marco , Hautier Geoffroy
Published: February 2020

The Pauling rules have been used for decades to rationalise the crystal structures of ionic compounds. Despite their importance, there has been no statistical assessment of the performances of these five empirical rules so far. Here, we rigorously and automatically test all five Pauling rules for a large data set of around 5000 known oxides. We discuss each Pauling rule separately, stressing their limits and range of application in terms of chemistries and structures. We conclude that only 13 % of the oxides simultaneously satisfy the last four rules, indicating a much lower predictive power than expected.
Solar‐Powered Organic Semiconductor–Bacteria Biohybrids for CO2 Reduction into Acetic Acid
Authors: Gai Panpan , Yu Wen , Zhao Hao , Qi Ruilian , Li Feng , Liu Libing , Lv Fengting , Wang Shu
Published: February 2020

An organic semiconductor–bacteria biohybrid photosynthetic system is used to efficiently realize CO2 reduction to produce acetic acid with the non‐photosynthetic bacteria Moorella thermoacetica. Perylene diimide derivative (PDI) and poly(fluorene‐co‐phenylene) (PFP) were coated on the bacteria surface as photosensitizers to form a p‐n heterojunction (PFP/PDI) layer, affording higher hole/electron separation efficiency. The π‐conjugated semiconductors possess excellent light‐harvesting ability and biocompatibility, and the cationic side chains of organic semiconductors could intercalate into cell membranes, ensuring efficient electron transfer to bacteria. Moorella thermoacetica can thus harvest photoexcited electrons from the PFP/PDI heterojunction, driving the Wood–Ljungdahl pathway to synthesize acetic acid from CO2 under illumination. The efficiency of this organic biohybrid is about 1.6 %, which is comparable to those of reported inorganic biohybrid systems.
Numerical simulation of granular mixing in a rotary drum using a generalized interpolation material point method
Authors: Zuo Zhijian , Gong Shuguang , Xie Guilan
Published: February 2020

Numerical simulations using a generalized interpolation material point method (GIMP) and material point method were introduced into the studying of granular mixing in a rotary drum. A Drucker–Prager model that has an equal size with a Mohr–Coulomb criterion was adopted to predict the failure behavior of granular matter. Experiments and discrete element method simulations were conducted to validate the models, and GIMP was finally used due to its accuracy and the ability for eliminating the crossing boundary noise. Velocity field of bed surface and standard deviation were used to measure the mixing performance. In particular, the influence of mesh size, elastic modulus, cohesion, and filling level were investigated. The results of simulations show that the utilization of GIMP significantly reduces the computing cost of simulation. The analysis of mixing performance shows that mixing performance decreases with the increase of elastic moduli, cohesion of granular matter, and filling levels.
Changes in rheological properties of polyvinyl chloride plastisols with storage time
Authors: Ji Yubi , Tang Anjiang , Yang Zhao , Luo Heng , Tan Hong
Published: February 2020

In this study, the changes in the rheological curves of polyvinyl chloride (PVC) plastisols with increasing storage time and the factors affecting these changes were studied. The results show that with increasing storage time, all the “viscosity–temperature” and “viscosity–time” rheological curves of PVC plastisols exhibit nonnormal distribution change trends, that is, the viscosity first decreases, and then changes from slow increasing to rapid increasing, forming a shoulder peak, reaches to the maximum value and gradually decreases. With increasing storage time, the complex viscosities of PVC plastisols increased generally in the first, the second, and the fourth stages, and the gelation process shortened in the third stage. The first and second stages of the viscosity changes reflect the “time–temperature” equivalence principle of PVC plastisol in suspension stage. However, the maximum viscosity of PVC plastisol corresponding to temperature Tηmax does not change with increasing storage time.
Ethylene vinyl acetate copolymer/halloysite nanotubes nanocomposites with enhanced mechanical and thermal properties
Authors: Zubkiewicz Agata , Szymczyk Anna , Paszkiewicz Sandra , Jędrzejewski Roman , Piesowicz Elżbieta , Siemiński Jakub
Published: February 2020

Ethylene vinyl acetate (EVA) nanocomposites filled with halloysite nanotubes (HNTs) were prepared by melt compounding. The homogenous dispersion of HNTs into the EVA matrix was evaluated by SEM and TEM analysis. The addition of HNTs does not influence on the phase separation structure and crystallinity of EVA nanocomposites. Due to the reinforcing effect of HNTs embedded in the EVA elastomer matrix, along with an increase of HNTs concentration, the improvement in tensile properties, by means of modulus at an elongation of 100% and tensile strength, was observed. It was found that tensile strength increased by 27% for EVA nanocomposite with 8 wt% of the HNTs. The values of elongation at break at low HNTs' loading increase and subsequently at higher loading are comparable to the neat EVA copolymer. The elastic deformability and reversibility of the EVA nanocomposites with different HNTs content was analyzed. The cyclic tensile tests showed that prepared nanocomposites have values of permanent set slightly higher than for neat EVA copolymer. Furthermore, the limiting oxygen index value for the EVA based nanocomposite with the highest HNTs content (8 wt%) increased from 19.5 to 24.8%. The results show, that thermo‐oxidative stability were improved by the incorporation of HNTs into EVA copolymer matrix.
Freeze‐dried graphene oxide modified with trimethylhexamethylene in the mix solvent for improved anti‐corrosion property of epoxy
Authors: Hou Weixin , Gao Ya , Wang John , Blackwood Daniel J. , Teo Serena
Published: February 2020

Graphene oxide (GO) reinforcement to enhance the property of epoxy has been reported many times; with most of the papers focusing on how to modify GO with different functional groups to achieve better dispersion. Here, the importance of the preparation route on the coating systems performance was investigated. It was found that a mixed polar/nonpolar solvent BuOH/xylene (3/1 vol/vol) was the best choice for forming the epoxy/GO coatings. Furthermore, it was found that when the freeze‐dried GO sonicated with the curing agent trimethylhexamethylene diamine in the mix solvent, the as‐prepared coating exhibited best performance, including better GO dispersion and hydrophobicity, higher adhesion, and anti‐corrosion property. Without any additional chemical to modify the GO, this optimized preparation route for epoxy/GO coatings will provide a guide for future similar research works, especially for the GO dispersion in nonaqueous systems.
Serendipitous discovery of a brightening quasar at redshift z = 3.68
Authors: Selman Fernando J. , Bian Fuyan , Blanchard Israel , Brillant Stephane , Coccato Lodovico , Cristiani Stefano , Hibon Pascale , Kakkad Darshan , Mehner Andrea , Moehler Sabine , Parraguez Diego , Reyes Claudia , Rivinius Thomas , Vera Sergio , Vogt Frédéric P. A. , Weilbacher Peter M. , Yang Bin
Published: February 2020

We report the serendipitous discovery of a redshift 3.68 quasar while validating the star WD 0308‐565 as a spectrophotometric standard star for the Multi‐Unit Spectroscopic Explorer (MUSE) calibration plan. Based on the MUSE observations, the luminosity of the quasar at 1350A (L1350) is 4.71 × 1045 erg s−1. The black hole mass is 2.5 × 109 Mʘ, and bolometric luminosity is 1.57 × 1047 erg s−1. Present in the field of view of a star in the calibration plan of the instrument makes this a very valuable quasar as it will receive many repeated visits in the coming years making it an ideal candidate for reverberation mapping studies.
Current Understanding of Nonaqueous Electrolytes for Calcium‐Based Batteries
Authors: Melemed Aaron M. , Khurram Aliza , Gallant Betar M.
Published: February 2020

Calcium metal batteries are receiving growing research attention due to significant breakthroughs in recent years that have indicated reversible Ca plating/stripping with attractive Coulombic efficiencies (90–95 %), once thought to be out of reach. While the Ca anode is often described as being surface film‐controlled, the ability to access reversible Ca electrochemistry is highly electrolyte‐dependent in general, which affects both interfacial chemistry on plated Ca along with more fundamental Ca2+/Ca redox properties. This minireview describes recent progress towards a reversible Ca anode from the point of view of the most successful electrolyte chemistries identified to date. This includes, centrally, what is currently known about the Ca2+ solvation environment in these systems. Experimental (physico‐chemical and spectroscopy) and computational results are summarized for the two major solvent classes – carbonates and ethers – that have yielded promising results so far. Current knowledge gaps and opportunities to improve fundamental understanding of Ca2+/Ca redox are also identified.
Herstellung gekrümmter tragender Betonbauteile auf einem formflexiblen Schalungswerkzeug
Authors: Heinlein Ulli , Fraundorfer Andreas , Katona Sebastian , Wimmer Matthias
Published: February 2020

Dreidimensional gekrümmte Bauformen aus Beton können bei repräsentativen Gebäuden optische Akzente setzen oder auch effiziente Tragsysteme bilden. Allerdings sind solche Strukturen bis heute durch einen hohen Arbeits‐ und Ressourcenaufwand im Schalungsbau gekennzeichnet und werden neben dem Aspekt der Nachhaltigkeit auch durch hohe Realisierungskosten belastet. Um den ökonomischen wie ökologischen Einfluss für den Schalungsbau zu minimieren, wurde bereits in früheren Konzepten ein flexibel rekonfigurierbares Schalungswerkzeug vorgeschlagen, das mehrfach verwendbar ist und computergestützt immer wieder neu auf eine gewünschte Geometrie eingestellt werden kann. Die dafür geeignete Multipoint‐Tooling‐Technologie wird im Rahmen dieses Beitrags auf ein Schalungswerkzeug im Betonbau angewandt, mit dem Bauteile mit baupraktischen Querschnittsdicken hergestellt werden können. Es wird ein formflexibler Schalungsprototyp zur Verwendung in Fertigteilwerken sowie zur Nutzung auf der Baustelle vorgestellt. Weiterhin beschreibt der Beitrag den gesamten Fertigungsprozess mit den benötigten Modulen zur Einstellung des Werkzeugs, der Abschalung und dem Betoneinbau. Anschließend wird gezeigt, dass mit diesem Ansatz freigeformte monolithische Betonquerschnitte für Wand‐ und Deckenelemente hergestellt werden können.
Impact of postoperative complications on survival after oesophagectomy for oesophageal cancer
Authors: Bundred J R , Hollis A C , Evans R , Hodson J , Whiting J L , Griffiths E A
Published: February 2020

Background

Recent evidence suggests that complications after oesophagectomy may decrease short- and long-term survival of patients with oesophageal cancer. This study aimed to analyse the impact of complications on survival in a Western cohort.

Methods

Complications after oesophagectomy were recorded for all patients operated on between January 2006 and February 2017, with severity defined using the Clavien–Dindo classification. Associations between complications and overall and recurrence-free survival were assessed using univariable and multivariable Cox regression models.

Results

Of 430 patients, 292 (67·9 per cent) developed postoperative complications, with 128 (39·8 per cent) classified as Clavien–Dindo grade III or IV. No significant associations were detected between Clavien–Dindo grade and either tumour (T) (P = 0·071) or nodal (N) status (P = 0·882). There was a significant correlation between Clavien–Dindo grade and ASA fitness grade (P = 0·032). In multivariable analysis, overall survival in patients with Clavien–Dindo grade I complications was similar to that in patients with no complications (hazard ratio (HR) 0·97, P = 0·915). However, patients with grade II and IV complications had significantly shorter overall survival than those with no complications: HR 1·64 (P = 0·007) and 1·74 (P = 0·013) respectively.

Conclusion

Increasing severity of complications after oesophagectomy was associated with decreased overall survival. Prevention of complications should improve survival.
Open access availability of anatomy papers presented at meetings of the American and British Associations of Clinical Anatomists
Authors: Miller George W. , Stoner Rebecca , Boissaud‐Cooke Matthew A. , Lim Joseph , Furness Hugh , Putt Oliver , Lewis Thomas L.
Published: February 2020

Introduction: Dissemination of research depends on published work being accessible. In many disciplines open access (OA) research is more frequently cited, although this has never before been demonstrated amongst anatomy publications. The objective of this study was to assess a selection of published anatomy papers to determine the effect of gold and bronze OA availability on citation rates.

Materials and Methods: Taken together, 625 peer‐reviewed publications were identified from 2927 abstracts presented at meetings of AACA (2003–2010) and BACA (2000–2015).

Results: In total 18.75% (69 of 368) of papers presented at BACA and 21.79% (56 of 257) of those presented at AACA reached OA publication.  Citation rates are significantly higher amongst OA papers as compared to non‐OA papers presented at these two anatomy conferences (OA 18.95, Non‐OA 15.14 p = 0.047). OA papers were most commonly themed around education and pure anatomy.

Conclusions: The average OA publication rate of 20.0% in anatomical research arising from these conferences is significantly lower than the average rate for scientific research. Citation rates are significantly higher amongst OA anatomy papers presented at these two conferences.
Implementation of the augmented reality to electronic practice
Authors: Selek Murat , Kıymaz Yunus E.
Published: February 2020

This study focuses on the application of augmented reality (AR) to electronic practice and its impact on the success of student. The developed application in this study has a recognition‐based system structure. The Unity3D platform and the Vuforia AR software development kit are used to perform the application. Flowcharts have been prepared for each electronic experiment and the audio files and the texts to be displayed on the screen have been used to improve interaction with the user. To test the effect of AR application on student success, an experimental study was also conducted on two groups of students (control group [non‐using AR] and test group [using AR]). The data obtained from the experimental study have been analyzed using independent sample t test. According to t‐test result at 95% confidence level, the probability value p = .002113432 < .05 for the use of AR is found. These results show that the use of AR in electronic practice makes a significant difference in student success.