bluuebunny/crossref_metadata_2025 huggingface dataset:
Correction: The absolute configurations of hyperilongenols A–C: rare 12,13-seco-spirocyclic polycyclic polyprenylated acylphloroglucinols with enolizable β,β′-tricarbonyl systems from Hypericum longistylum Oliv.
Authors: Zhang Na , Shi Zhengyi , Guo Yi , Xie Shuangshuang , Qiao Yuben , Li Xiao-Nian , Xue Yongbo , Luo Zengwei , Zhu Hucheng , Chen Chunmei , Hu Linzhen , Zhang Yonghui
Published: April 2019

Correction for ‘The absolute configurations of hyperilongenols A–C: rare 12,13-seco-spirocyclic polycyclic polyprenylated acylphloroglucinols with enolizable β,β′-tricarbonyl systems from Hypericum longistylum Oliv.’ by Na Zhang, et al., Org. Chem. Front., 2019, DOI: 10.1039/c9qo00245f.
An in situ formed graphene oxide–polyacrylic acid composite cage on silicon microparticles for lithium ion batteries via an esterification reaction
Authors: Jung Chul-Ho , Kim Kyeong-Ho , Hong Seong-Hyeon
Published: April 2019

An in situ formed covalent bond between graphene oxide–PAA binder successfully confined Si microparticles for use in lithium ion batteries.
Planar NiC3 as a reversible anode material with high storage capacity for lithium-ion and sodium-ion batteries
Authors: Zhu Changyan , Qu Xin , Zhang Min , Wang Jianyun , Li Quan , Geng Yun , Ma Yanming , Su Zhongmin
Published: April 2019

The storage capacity for Li and Na on the entirely NiC3 monolayer reaches the highest value of 1698 mA h g−1 among the reported 2D materials. Meanwhile, fast charge/discharge capability and low open-circuit voltage also demonstrate that the entire NiC3 monolayer is a desirable anode material for LIBs and SIBs.
Influence of composition and structure on the thermal quenching of the 5d–4f emission of Eu2+ doped M–Si–N (M = alkali, alkaline earth, rare earth) nitridosilicates
Authors: ten Kate Otmar M. , van Ommen J. Ruud , Hintzen H. T. (Bert)
Published: April 2019

Thermal quenching of the Eu2+ emission in the nitridosilicates has been analysed and related to structure and composition.
A Scoping Review of the Involvement of Children's Communication Partners in Aided Augmentative and Alternative Communication Modeling Interventions
Authors: Biggs Elizabeth E. , Carter Erik W. , Gilson Carly B.
Published: April 2019

Purpose

The purpose of this study was to inform practice and research by identifying and synthesizing research on interventions in which natural communication partners implemented aided augmentative and alternative communication (AAC) modeling strategies.

Method

A scoping review yielded 29 studies. Data were charted related to participant characteristics, intervention characteristics, partner instruction and assessment, and partner perspectives of social validity.

Results

More than 157 peer and 100 adult communication partners (e.g., parents, special educators, paraprofessionals) implemented aided AAC modeling strategies within included studies. To teach communication partners intervention strategies, researchers frequently reported using (a) oral instruction, (b) modeling, and (c) practice or application opportunities with performance feedback. Partner instruction frequently involved both training and concurrent support (e.g., coaching, facilitation, consultation, follow-up support).

Conclusion

Findings from this review inform the design and delivery of aided AAC modeling interventions by children's natural communication partners. Findings also highlight important avenues for enhancing the rigor of future research on interventions involving aided AAC modeling, including the quality of reporting and application of principles from implementation science.

Supplemental Material

https://doi.org/10.23641/asha.8038505
Hybrid flow shop scheduling problem in ubiquitous manufacturing environment
Authors: Wu Xiuli , Li Jing , Sun Lin
Published: April 2019

As a new smart manufacturing mode, Internet of manufacturing things could collect information from production line and help to make a timely and accurate decision. However, this new mode poses new challenges to production operation management. This article focuses on the hybrid flow shop scheduling problem in ubiquitous manufacturing environment. Advanced wireless devices such as radio frequency identification are deployed to enable interconnection and perception among workers, materials and equipment in shop floor. The scheduling optimisation models for the planning layer and the scheduling layer are established, respectively. The evolutionary game algorithm is proposed to optimise the assignment of daily production tasks in the planning layer. According to the real‐time situations of various production resources, the non‐dominated sorted genetic algorithm is utilised to optimise the real‐time scheduling of daily tasks in the scheduling layer. Between the two layers, real‐time production information is exchanged by advanced wireless devices. Finally, two production scenarios in off‐season and peak‐season are presented. The experimental results verify the efficiency and the effectiveness of the proposed approach under different production conditions.
Minimising torque ripple of SRM by applying DB‐DTFC
Authors: Zhang Wen , Xu Ai'de , Han Lele , Wang Shenghao
Published: April 2019

Since the traditional direct torque control (DTC) of switched reluctance motors (SRMs) has the shortcomings of large torque ripple and non‐constant switching frequency, this study proposes the deadbeat‐direct torque and flux‐linkage control (DB‐DTFC) method for SRM. By analysing the basic principles of SRM, a discrete‐time model is established to predict the future states of the SRM drive system. With DB‐DTFC, the stator flux and torque can be manipulated during each pulse‐width modulation cycle to minimise torque ripple during operation. As a result, the proposed DB‐DTFC can minimise the torque ripple as well as apply space‐vector modulation with a constant switching frequency. Finally, to verify its effectiveness, DB‐DTFC was applied to the 15 kW three‐phase 12/8‐pole SRM test bench in real time and the results are compared with conventional DTC.
Experimental study of radiation characteristics and temperature distributions of gasoline and biomass flame
Authors: Liu Huawei , Zheng Shu , Wang Tieying
Published: April 2019

Gasoline and two types of biomass, i.e. shrub boughs and pine boughs were investigated experimentally. The gasoline was the mixture of 500 mL water and 300 mL 92‐octane gasoline. The experimental measurement was conducted on a device that contained a colour camera (SP‐20000C) and a fibre optic spectrometer (AvaSpec‐2048). The device captured spectral intensities via the spectrometer. Colour images were captured on the colour camera. The radiation characteristics, i.e. the wavelength‐dependent emissivity in this study, were determined with a multi‐wavelength thermometry in accordance with the spectral intensities. The results of emissivity were used so that the temperature distribution was calculated directly using the colour image, with the consideration of the broad response spectrum of the channels of the camera. Radiation characteristics and temperature distributions for these three types of flame were experimentally determined and presented. Results show that, in the visible light region, excluding the spectral lines of alkali metals, the continuous radiation of these flames should result from the similar substance. What is more, the combustion of gasoline (watered) is the most incomplete, resulting in a mass of product of incomplete reaction, and pine boughs were more flammable than shrub boughs.
Research on optimisation configuration for energy hub based on user's comfort index
Authors: Yao Zongjun , Zhao Yan , Shao Qianzhi , Huang Jinfeng , Jin Hongyang
Published: April 2019

As an important part of a multi‐energy system, the energy hub (EH) accommodates a wide range of input sources and diversified load types. Optimising the equipment type and capacity of the EH is the basis for ensuring the safe and economic operation of the EH. In this context, the basic concepts and models of the EH are first outlined. Then, to reduce the user's electricity cost and user comfort as the optimisation goal, the tie line power constraint and the purchase and sale power state constraints are considered comprehensively.
Enhanced n‐type conductivity of 6H‐SiC nanowires by nitrogen doping
Authors: Li Shanying , Li Jie , Su Qing , Liu Xiangyun , Zhao Haipeng , Ding Mingjie
Published: April 2019

The N‐doped n‐type 6H‐SiC (silicon carbide) nanowires (NWs) were synthesised via an electrospinning fibre carbothermal method by employing ammonia as a dopant. The structure characterisations reveal that the as‐synthesised 6H‐SiC NWs have a hexagonal structure. The nano‐field‐effect transistors based on individual N‐doped 6H‐SiC NWs were constructed, and the electrical measurements indicated that the N‐doped 6H‐SiC NWs have n‐type semiconductors properties with a high carrier concentration of 2.1 × 1019 cm−3 and a low resistivity of 0.1 Ω cm. The field emission characterisations of N‐doped 6H‐SiC NWs demonstrate that the turn‐on electric field (Eto) is 7.6 Vμm−1, and the threshold electric field (Eth) is 8.5 Vμm−1. The as‐synthesised N‐doped 6H‐SiC NWs with enhanced n‐type conductivity will be a very attractive candidate for nanoelectronics devices in the future.
Synthetic mechanisms of K2−xMn8O16 nanorods for removal of acetaldehyde
Authors: Chen Ying , Shi Jianling , Liang Yuning
Published: April 2019

Volatile organic compounds (VOCs) severely threaten the ecological environment and human health even at low concentration because most of them are toxic, mutagenic and carcinogenic. In this study, a hydrothermal synthetic manganese‐based compound, namely cryptomelane manganese oxide (K2−xMn8O16) nanorod aerogels and a redox product of K2S2O8 and MnSO4, is chosen as an adsorbent for acetaldehyde removal. Insights were gained into the functions of potassium sulphate (K2SO4) and the mechanisms of generating nanorods in the solution phase. The structures, morphologies, specific area and pore size distribution of composites were characterised by N2 adsorption–desorption isotherms, scanning electron microscopy, and X‐ray diffraction, and the results showed that VOCs removal by adsorption onto K2−xMn8O16 nanorod aerogels could be used as a potential method for eliminating VOCs in terms of efficiency.
Expanding associations in the Vela-Puppis region
Authors: Cantat-Gaudin T. , Jordi C. , Wright N. J. , Armstrong J. J. , Vallenari A. , Balaguer-Núñez L. , Ramos P. , Bossini D. , Padoan P. , Pelkonen V. M. , Mapelli M. , Jeffries R. D.
Published: April 2019

Context. The Vela-Puppis region is known to host the Vela OB2 association as well as several young clusters featuring OB and pre-main-sequence stars. Several spatial and kinematic subgroups have been identified in recent years.

Aims. By grouping stars based on their positions and velocity, we can address the question of the dynamical history of the region and the mechanisms that drove stellar formation. TheGaiaDR2 astrometry and photometry enables us to characterise the 3D spatial and 3D kinematic distribution of young stars and to estimate the ages of the identified components.

Methods. We used an unsupervised classification method to group stars based on their proper motions and parallax. We studied the expansion rates of the different identified groups based on 3D velocities and on corrected tangential velocities. We used theoretical isochrones to estimate ages.

Results. The young stars can be separated into seven main groups of different ages and kinematical distribution. All groups are found to be expanding, although the expansion is mostly not isotropic.

Conclusions. The size of the region, the age substructure, and the anisotropic expansion rates are compatible with a prolonged period of star formation in a turbulent molecular cloud. The current kinematics of the stars cannot be explained by internal processes alone (such as gas expulsion).
Les CAR-T cells, des cellules tueuses spécifiques d’antigènes tumoraux
Authors: Catros Véronique
Published: April 2019

Les lymphocytes T présentent des fonctions lytiques puissantes et leur adressage spécifique aux cellules tumorales afin de les détruire est un enjeu majeur. Leur ingénierie par transfert d’une construction génétique codant un fragment d’anticorps spécifique de la molécule CD19, exprimée par les lymphocytes B, fusionné à une unité de transduction d’un signal T a conduit à des résultats cliniques importants dans des formes avancées de lymphomes. Ces lymphocytes T modifiés, appelés CAR-T cells, ou plus simplement CAR pour chimeric antigen receptor, ont reçu une approbation par la Food and drug administration américaine en 2017 pour les deux premiers médicaments de thérapie cellulaire : le Kymriah™ et le Yescarta™. Ces CAR, conçus pour le traitement d’hémopathies malignes, permettent d’envisager la construction d’autres CAR dirigés, eux, contre des tumeurs solides. De nouvelles générations de CAR visent à mieux contrôler leur prolifération et à améliorer leurs fonctions in vivo grâce à la mise en place de mécanismes d’inactivation inductibles. Le développement des multi-CAR, des CAR spécifiques de plusieurs cibles, et leur combinaison aux inhibiteurs de points de contrôle immunitaires ouvrent une nouvelle ère pour l’immunothérapie des tumeurs.
Optimal production lot size under backup agreement allowing substitute products
Authors: Tsai Wen-Chin , Wang Chih-Hsiung
Published: April 2019

In the fashion industry, a flexible backup agreement contract allows the retailer to order a partial amount from the backup quantity to allay the risk of uncertain market demand. However, under such a contract, the manufacturer faces the risk of bearing a huge leftover if the quantity realized by the retailer in backup is small. Accordingly, the present study considers a modified backup agreement in which the manufacturer is permitted to urgently purchase substitute products to satisfy the backup order from a third-party supplier, but at a unit purchase cost greater than the original unit manufacturing cost. The corresponding expected total profit function for the manufacturer is established and shown to be concave. The profit function is used to explore various useful properties for determining the optimal production lot size. In addition, an illustrated numerical example is provided to analyze the impact of the backup contract terms on the optimal production lot size and manufacturer’s profit.
Reconsidering the HbA1c Cutoff for Diabetes Diagnosis Based on a Large Chinese Cohort
Authors: Qi Jiying , Su Yang , Song Qianqian , Ding Zhaojun , Cao Min , Cui Bin , Qi Yan
Published: April 2019

Introduction The HbA1c has been considered as the ‘gold standard’ in diabetes diagnosis and management, however, age, gender and body mass index (BMI) might have certain effects on HbA1c. We are aiming to further investigate the correlation between age and HbA1c, and whether it was affected by gender and BMI.

Methods A cross-sectional survey including 135,893 nondiabetic individuals who took the physical examination between 2013 and 2017 was conducted. The subjects were grouped by gender, age and BMI, and the interactive and independent effects of the 3 factors on the HbA1c were detected. The median and 95% confidence interval (CI) of HbA1c levels were calculated.

Results The HbA1c levels gradually increased along with age, both in female and male, and there is a positive association between BMI and the HbA1c. The difference on HbA1c in gender was associated with both age and BMI, the age-related increase in HbAlc was accentuated in the subgroup with higher BMI, and there was a marked accentuation of the positive association between BMI and HbA1c as age increased. In almost all the young and middle-aged (aged 20–59) subgroups, the 97.5th percentiles of HbA1c levels were lower than 6.5%, suggesting that the single HbA1c cutoff value is probably not applicable to the young and middle-aged population.

Conclusions We recommend that the effects of age, gender and BMI should be taken into consideration when using HbA1c for the diagnosis and management of diabetes, especially in the young and middle-aged population.
Bewegung und seelische Gesundheit
Authors: Fröhlich-Gildhoff Gabriele
Published: April 2019

Körperliche Aktivität im aeroben Bereich hebt bei seelisch gesunden Menschen das
Wohlbefinden, die Stimmung ist auch Stunden nach der Aktivität gehoben. Somit
wirkt es sich langfristig präventiv auf die seelische Gesundheit aus. Bei
Menschen mit depressiven Erkrankungen oder Ängsten können körperliche
Aktivitäten als therapeutische Maßnahmen mit deutlicher Symptomreduktion genutzt
werden. Insbesondere bei leichten bis mittelgradigen Depressionen erreichen sie
gleich gute Ergebnisse wie eine antidepressive Medikation, bei der
Rezidivprophylaxe ist die körperliche Aktivität der Medikation sogar
überlegen.
Accuracy Evaluation of Five Blood Glucose Monitoring Systems in
Patients from Different Departments
Authors: Li Xiaona , Zheng Suhua , Pan Suiyue , Yan Ting , Di Jie , Yang Yinian , Cheng Jinluo
Published: April 2019

Background Self-monitoring of blood glucose (SMBG) systems are
expected to be accurate and provide reliable results. The international
standard ISO (International Organization for Standardization) 15197:2013 is
widely accepted for the accuracy evaluation for SMBG systems. Accuracy
evaluation was performed for 5 different SMBG systems in patients from
multi-departments at the hospital.

Method A total of 120 patients from Changzhou Second People’s
Hospital (Changzhou, China) were randomized and enrolled in the study.
Accuracy evaluation was performed for 5 different SMBG systems: Gold AQ
(Sinocare), Freestyle Optium Xceed (Abbott), Contour TS (Bayer), OneTouch
Ultra (J&J) and Accu-Chek Performa (Roche). For each system,
comparison measurements were performed with YSI 2300 STAT PLUS Glucose and
Lactate Analyzer and Roche Cobas 8000 Modular Analyzer.

Results All 5 systems showed that 100% of results fall within
consensus error grid Zones A and B. Compared with YSI 2300 or Roche Cobas
8000 Modular Analyzer, Gold AQ system showed the highest accuracy. The
linearity analysis also showed that Gold AQ had the highest correlation
coefficient.

Conclusion Compared with other SMBG systems, Gold AQ Glucose
Monitoring System manufactured by Sinocare Inc. had the highest accuracy in
measuring blood glucose level in patients from multi-departments at this
hospital.
Emotionen durch Farben entschlüsseln –
Lüscher-Color-Diagnostik in der heutigen Praxis
Authors: Krebs Johannes
Published: April 2019

Psychische Erkrankungen belasten unser Gesundheitssystem in immer stärkerem Maße.
Das Ziel liegt daher im frühzeitigen Erkennen psychovegetativer Störungen, um
langfristige individuelle und volkswirtschaftliche Schäden zu vermeiden. Dazu
werden aus Kostengründen meist Fragebögen verwendet, deren wissenschaftliche
Evidenz jedoch oft zweifelhaft ist, da sie vom Probanden willentlich beeinflusst
werden können. Der Beitrag plädiert für den Einsatz komplementärer Verfahren und
stellt die Lüscher-Color-Diagnostik vor, deren großer Vorteil in der
Nichtbeeinflussbarkeit des Testes liegt. Der Test beschreibt anhand seiner 8
Untertests das emotionale Profil des Betroffenen. Zwei Fallbeispiele aus der
zahnärztlichen Praxis visualisieren die Vorgehensweise beim
Lüscher-Color-Test.
Direct Synthesis of Deuterium-Labeled O-, S-, N-Vinyl Derivatives from Calcium Carbide
Authors: Ledovskaya Maria S. , Voronin Vladimir V. , Rodygin Konstantin S. , Posvyatenko Alexandra V. , Egorova Ksenia S. , Ananikov Valentine P.
Published: April 2019

A novel methodology for the preparation of trideuterovinyl derivatives of high purity directly from alcohols, thiols, and NH-compounds was developed. Commercially available calcium carbide and D2O acted as a D2-acetylene source, and DMSO-d
6 was used to complete the formation of the D2C=C(D)–X fragment (X = O, S, N). Polymerization of a selected trideuterovinylated compound showed a very promising potential of these substances in the synthesis of labeled polymeric materials. Biological activity of the synthesized trideuterovinyl derivatives was evaluated and the results indicated a significant increase of cytotoxicity upon deuteration.
Organocatalytic Gram-Scale Synthesis and Alkylation of Heteroaryl and Electron-Rich Aryl α-Substituted γ-Lactones
Authors: Bos Maxence , Buttard Floris , Vallée Alexis , Riguet Emmanuel
Published: April 2019

The synthesis of γ-lactones α-substituted with heterocycles and electron-rich aromatic rings is described. The method, based on a sequence involving an organocatalytic addition of boronic acid to the 5-hydroxyfuran-2(5H)-one, followed by reduction and lactonization, gives access to broad range of γ-lactones on a gram scale. Among these, γ-lactones bearing a benzofuran, a benzothiophene, and an indole ring were alkylated in mild catalytic conditions to construct α-quaternary stereocenters. Interesting mild oxidation reaction, using molecular oxygen, was also highlighted during this study.
A novel underwater piezoelectric thruster with one single resonance mode
Authors: Li Xinjian , Chen Di , Jin Jiamei , Wang Liang
Published: April 2019

In this paper, a novel underwater piezoelectric thruster with one single resonance mode is proposed. The piezoelectric thruster consists of one piezoelectric transducer and two propellers. In order to relieve the bulky problem of underwater thrusters using a DC motor as the power source, the piezoelectric thruster adopts a full-open structure; thus, the piezoelectric thruster does not need additional sealing elements. Compared with underwater thrusters using a DC motor, the piezoelectric thruster has advantages of simple structure and small volume. By using piezoelectric ceramics, the first-order longitudinal mode of the transducer is excited to drive two propellers rotating in opposite directions. A prototype of the piezoelectric thruster is fabricated and experimentally investigated; it is 22 g in weight and 124 mm in length. The experimental results indicate that when the excitation voltage of the piezoelectric transducer is 300 Vpp, the rotational speed of the positive propeller is up to 1267 rpm and the stall torque is 1.71 mN m; meanwhile, the rotation speed of the negative propeller is up to 1203 rpm, and the stall torque is 1.75 mN m. When the piezoelectric thruster is working underwater, the average forward speed reaches 106.01 mm/s at 400 Vpp.
All inorganic solution processed three terminal charge trapping memory device
Authors: Mondal Sandip , Venkataraman V.
Published: April 2019

We demonstrate charge trapping memory devices comprising aluminum oxide phosphate (ALPO) blocking/indium gallium zinc oxide charge-trapping/ALPO tunneling layers with a bottom-gated architecture fabricated by sol-gel process technique at temperatures as low as 300 °C. The memory device offers a large memory hysteresis of 13.5 V in the Id–Vg curve when the gate voltage is swept from −20 to +30 V and back. The true program-erase (P/E) window of 7 V is established for the P/E square pulse of ±20 V s−1. Good retention characteristic is confirmed within the experimental limit of 104 s. The P/E mechanism is illustrated by the complete band structure of the memory devices. We also demonstrate a control device without a charge trapping layer, which shows excellent thin film transistor characteristics.
Current-induced switching of YIG/Pt bilayers with in-plane magnetization due to Oersted fields
Authors: Mendil Johannes , Trassin Morgan , Bu Qingqing , Fiebig Manfred , Gambardella Pietro
Published: April 2019

We report on the switching of the in-plane magnetization of thin yttrium iron garnet (YIG)/Pt bilayers induced by an electrical current. The switching is either field-induced and assisted by a dc current, or current-induced and assisted by a static magnetic field. The reversal of magnetization occurs at a current density as low as 105 A/cm2 and magnetic fields of ∼40 μT, two orders of magnitude smaller than in ferromagnetic metals, and consistent with the weak uniaxial anisotropy of the YIG layers. We use the transverse component of the spin Hall magnetoresistance to sense the magnetic orientation of YIG while sweeping the current. Our measurements and simulations reveal that the current-induced effective field responsible for switching is due to the Oersted field generated by the current flowing in the Pt layer rather than by spin–orbit torques, and that the switching efficiency is influenced by pinning of the magnetic domains.
In situ X-ray photoelectron spectroscopy using a conventional Al-Kα source and an environmental cell for liquid samples and solid-liquid interfaces
Authors: Endo Raimu , Watanabe Daisuke , Shimomura Masaru , Masuda Takuya
Published: April 2019

X-ray photoelectron spectroscopy (XPS), which intrinsically requires vacuum, was used to characterize chemical species in a liquid using laboratory XPS apparatus equipped with a conventional Al-Kα source and an environmental cell with an ultra-thin silicon nitride membrane as a quasi-transparent window for the transmission of X-rays and photoelectrons. Aqueous solutions of cesium chloride at different concentrations were encapsulated in the cells, and the membrane in contact with the solution was irradiated with X-rays to collect the photoelectrons emitted from the chemical species in a liquid through the membrane. Cs 4d photoelectron peaks were observed, and the peak intensity increased proportionally with the concentration. Thus, the quantitative analysis of solution species by this method is demonstrated.
Disentangling the abundance–impact relationship for invasive species
Authors: Bradley Bethany A. , Laginhas Brittany B. , Whitlock Raj , Allen Jenica M. , Bates Amanda E. , Bernatchez Genevieve , Diez Jeffrey M. , Early Regan , Lenoir Jonathan , Vilà Montserrat , Sorte Cascade J. B.
Published: April 2019

To predict the threat of biological invasions to native species, it is critical that we understand how increasing abundance of invasive alien species (IAS) affects native populations and communities. The form of this relationship across taxa and ecosystems is unknown, but is expected to depend strongly on the trophic position of the IAS relative to the native species. Using a global metaanalysis based on 1,258 empirical studies presented in 201 scientific publications, we assessed the shape, direction, and strength of native responses to increasing invader abundance. We also tested how native responses varied with relative trophic position and for responses at the population vs. community levels. As IAS abundance increased, native populations declined nonlinearly by 20%, on average, and community metrics declined linearly by 25%. When at higher trophic levels, invaders tended to cause a strong, nonlinear decline in native populations and communities, with the greatest impacts occurring at low invader abundance. In contrast, invaders at the same trophic level tended to cause a linear decline in native populations and communities, while invaders at lower trophic levels had no consistent impacts. At the community level, increasing invader abundance had significantly larger effects on species evenness and diversity than on species richness. Our results show that native responses to invasion depend critically on invasive species’ abundance and trophic position. Further, these general abundance–impact relationships reveal how IAS impacts are likely to develop during the invasion process and when to best manage them.
Regulatory T cells limit unconventional memory to preserve the capacity to mount protective CD8 memory responses to pathogens
Authors: Da Costa Andreia S. , Graham Jessica B. , Swarts Jessica L. , Lund Jennifer M.
Published: April 2019

Significance

T cell-mediated immune memory provides the host with the capacity to rapidly and efficiently respond to pathogen reencounter, often without symptoms or disease. In addition to conventional memory T cell responses that are pathogen-specific, there also exists a subset of unconventional memory T cells that share many of the characteristics of conventional memory T cells without the initiating requirement of cognate antigen recognition. Here, we demonstrate a mechanism whereby regulatory T cells limit the expansion of these unconventional memory T cells to preserve a host’s capacity to mount a memory CD8 T cell response that remains protective upon pathogen reencounter.
PGE
2
signaling via the neuronal EP2 receptor increases injury in a model of cerebral ischemia
Authors: Liu Qingkun , Liang Xibin , Wang Qian , Wilson Edward N. , Lam Rachel , Wang Jing , Kong William , Tsai Connie , Pan Tingting , Larkin Paul B. , Shamloo Mehrdad , Andreasson Katrin I.
Published: April 2019

Significance

Stroke is the leading cause of disability and fifth leading cause of mortality in the United States. Previous studies demonstrate a highly protective effect of inhibiting cyclooxygenase-2 (COX-2) after stroke, indicating that downstream PGE
2
signaling pathways cause cerebral ischemic injury. Using conditional knockout strategies to study the role of PGE
2
EP2 signaling in a model of cerebral ischemia, we determine that neuronal EP2 signaling, which is highly induced following cerebral ischemia, increases cerebral injury. We demonstrate that EP2 blockade in adult mice is highly cerebroprotective and myeloid EP2 signaling increases the poststroke innate immune response. Additionally, the present results differ from previous studies of congenitally null EP2 mice, reflecting a potential confounding effect of congenital deletion of EP2.
Molecular engineering of an efficient four-domain DAF-MCP chimera reveals the presence of functional modularity in RCA proteins
Authors: Panwar Hemendra Singh , Ojha Hina , Ghosh Payel , Barage Sagar H. , Raut Sunil , Sahu Arvind
Published: April 2019

Significance

Complement regulation is critical for protecting the body’s own cells from homologous complement. This function is primarily mediated by the regulators of complement activation (RCA) proteins through two functional mechanisms termed decay-accelerating activity (DAA) and cofactor activity (CFA). Here, we show the presence of functional modularity in the RCA proteins. We demonstrate that the basic functional blocks for DAA and CFA in these proteins are formed by only two domains and that these are arranged in a specific order. Furthermore, we show that linking functional blocks of the decay-accelerating factor and membrane cofactor protein—which possess DAA and CFA, respectively—and adding C-terminal domains for enhancing avidity toward C3b/C4b results in a regulator molecule with dual activity.
Widespread nitrous oxide undersaturation in farm waterbodies creates an unexpected greenhouse gas sink
Authors: Webb Jackie R. , Hayes Nicole M. , Simpson Gavin L. , Leavitt Peter R. , Baulch Helen M. , Finlay Kerri
Published: April 2019

Nitrogen pollution and global eutrophication are predicted to increase nitrous oxide (N2O) emissions from freshwater ecosystems. Surface waters within agricultural landscapes experience the full impact of these pressures and can contribute substantially to total landscape N2O emissions. However, N2O measurements to date have focused on flowing waters. Small artificial waterbodies remain greatly understudied in the context of agricultural N2O emissions. This study provides a regional analysis of N2O measurements in small (<0.01 km2) artificial reservoirs, of which an estimated 16 million exist globally. We show that 67% of reservoirs were N2O sinks (−12 to −2 μmol N2O⋅m−2⋅d−1) in Canada’s largest agricultural area, despite their highly eutrophic status [99 ± 289 µg⋅L−1chlorophyll-a (Chl-a)]. Generalized additive models indicated that in situ N2O concentrations were strongly and nonlinearly related to stratification strength and dissolved inorganic nitrogen content, with the lowest N2O levels under conditions of strong water column stability and high algal biomass. Predicted fluxes from previously published models based on lakes, reservoirs, and agricultural waters overestimated measured fluxes on average by 7- to 33-fold, challenging the widely held view that eutrophic N-enriched waters are sources of N2O.
Structure of the Ty3/Gypsy retrotransposon capsid and the evolution of retroviruses
Authors: Dodonova Svetlana O. , Prinz Simone , Bilanchone Virginia , Sandmeyer Suzanne , Briggs John A. G.
Published: April 2019

Retroviruses evolved from long terminal repeat (LTR) retrotransposons by acquisition of envelope functions, and subsequently reinvaded host genomes. Together, endogenous retroviruses and LTR retrotransposons represent major components of animal, plant, and fungal genomes. Sequences from these elements have been exapted to perform essential host functions, including placental development, synaptic communication, and transcriptional regulation. They encode a Gag polypeptide, the capsid domains of which can oligomerize to form a virus-like particle. The structures of retroviral capsids have been extensively described. They assemble an immature viral particle through oligomerization of full-length Gag. Proteolytic cleavage of Gag results in a mature, infectious particle. In contrast, the absence of structural data on LTR retrotransposon capsids hinders our understanding of their function and evolutionary relationships. Here, we report the capsid morphology and structure of the archetypal Gypsy retrotransposon Ty3. We performed electron tomography (ET) of immature and mature Ty3 particles within cells. We found that, in contrast to retroviruses, these do not change size or shape upon maturation. Cryo-ET and cryo-electron microscopy of purified, immature Ty3 particles revealed an irregular fullerene geometry previously described for mature retrovirus core particles and a tertiary and quaternary arrangement of the capsid (CA) C-terminal domain within the assembled capsid that is conserved with mature HIV-1. These findings provide a structural basis for studying retrotransposon capsids, including those domesticated in higher organisms. They suggest that assembly via a structurally distinct immature capsid is a later retroviral adaptation, while the structure of mature assembled capsids is conserved between LTR retrotransposons and retroviruses.
Influenza A virus mimetic nanoparticles trigger selective cell uptake
Authors: Maslanka Figueroa Sara , Veser Anika , Abstiens Kathrin , Fleischmann Daniel , Beck Sebastian , Goepferich Achim
Published: April 2019

Significance

The identification and targeting of specific cell types are major shortcomings of nanoparticles (NPs) for theragnostic applications. Even in simple cell culture systems, today’s NPs cannot unequivocally distinguish target from off-target cells. To overcome this restraint, we designed NPs that identify cells in an influenza A virus-like manner. Our NPs probe mesangial cells for angiotensin-converting enzyme using angiotensin I (Ang-I) as substrate. The resulting enzymatic reaction transforms Ang-I into Ang-II. Binding of the latter to the Ang-II type-1 receptor (AT1R) confirms the cells’ identity and triggers NP uptake. The particles identified their target cells even with off-target cells present. With cell avidities similar to those of antibodies, the particles are promising transporters for therapeutic and diagnostic applications with pinpoint accuracy.
Generation of hypoimmunogenic human pluripotent stem cells
Authors: Han Xiao , Wang Mengning , Duan Songwei , Franco Paul J. , Kenty Jennifer Hyoje-Ryu , Hedrick Preston , Xia Yulei , Allen Alana , Ferreira Leonardo M. R. , Strominger Jack L. , Melton Douglas A. , Meissner Torsten B. , Cowan Chad A.
Published: April 2019

Significance

To enable cell therapy on a broader scale, the development of universal donor stem cell products that can be administered to multiple patients in need has been proposed, yet a strategy controlling both adaptive and innate immune rejection has not been reported. In this study, we employed multiplex genome editing to selectively ablate the highly polymorphic HLA class Ia and class II molecules and introduced the immunoregulatory factors PD-L1, HLA-G, and CD47 to control T cell- and NK cell-mediated immune responses and macrophage engulfment in vitro and in vivo. Our strategy demonstrates the power of cell engineering and informs future studies aiming to generate “off-the-shelf” universal cell products that may make cell therapy available to a larger pool of patients.
Exploratory investigation of the anti-inflammatory effects of RNase A-treatedEnterococcus faecalisstrain EC-12
Authors: Tamaki Ryuji , Takahashi Mio , Tai Shoya , Makioka-Itaya Yuko , Ijich Tetsuo , Inoue Ryo
Published: April 2019

We previously reported that the major component of Enterococcus faecalis strain EC-12 (EC-12) inducing production of Interleukin (IL)-12 in mouse/human immune cells was its own RNA. This study aimed to investigate if RNase A-treated EC-12 could also produce IL-10 and to evaluate the possible effects of IL-10 produced by RNase A-treated EC-12. Three experiments were conducted: (1) Assessment of the effect of RNase A-treated EC-12 on transcriptome profiles and biological pathways in human peripheral blood mononuclear cells; (2) Determination of cytokine concentration in its culture supernatants; and (3) Supplementation of RNase A-treated EC-12 (RN) to mice with dextran sodium sulfate-induced colitis. Treatment of EC-12 with RNase A inhibited inflammatory response including the potency to induce IL-12 production, while it did not affect IL-10 production (Experiment 1 and 2). Colitis symptoms were milder in RN than in PBS-supplemented controls (Experiment 3). RNase A-treated EC-12 likely became an anti-inflammatory agent primarily inducing IL-10 production.
Curriculum coherence as perceived by district‐level stakeholders in large‐scale national curriculum reform in Finland
Authors: Sullanmaa Jenni , Pyhältö Kirsi , Pietarinen Janne , Soini Tiina
Published: April 2019

It has been suggested that curriculum coherence is crucial in successful educational reform. However, empirical research on the topic is still scarce. This study explores how the stakeholders involved in curriculum development at the district level perceived curriculum coherence. Survey data (n = 550) were analysed using structural equation modelling. A confirmatory factor analysis showed that curriculum coherence consists of three complementary components: consistency of the intended direction; an integrative approach to teaching and learning; and alignment between objectives, content and assessments. Moreover, the results showed that curriculum coherence contributes to the expected impact of the reform on the school level development. The study adds to the research on curriculum reform by showing that curriculum coherence is a central determinant of the reform taking root at the school level, and by introducing a scale for measuring perceptions of curriculum coherence within the context of large‐scale national curriculum reform.
A novel human IL2RB mutation results in T and NK cell–driven immune dysregulation
Authors: Fernandez Isabel Z. , Baxter Ryan M. , Garcia-Perez Josselyn E. , Vendrame Elena , Ranganath Thanmayi , Kong Daniel S. , Lundquist Karl , Nguyen Tom , Ogolla Sidney , Black Jennifer , Galambos Csaba , Gumbart James C. , Dawany Noor , Kelsen Judith R. , de Zoeten Edwin F. , Quinones Ralph , Eissa Hesham , Verneris Michael R. , Sullivan Kathleen E. , Rochford Rosemary , Blish Catherine A. , Kedl Ross M. , Dutmer Cullen M. , Hsieh Elena W.Y.
Published: April 2019

The pleiotropic actions of interleukin-2 (IL-2) are essential for regulation of immune responses and maintenance of immune tolerance. The IL-2 receptor (IL-2R) is composed of IL-2Rα, IL-2Rβ, and IL-2Rγ subunits, with defects in IL-2Rα and IL-2Rγ and their downstream signaling effectors resulting in known primary immunodeficiency disorders. Here, we report the first human defect in IL-2Rβ, occurring in two infant siblings with a homozygous IL2RB mutation in the WSXWS motif, manifesting as multisystem autoimmunity and susceptibility to CMV infection. The hypomorphic mutation results in diminished IL-2Rβ surface expression and dysregulated IL-2/15 signaling, with an anticipated reduction in regulatory T cells. However, in contrast to the IL-2Rβ−/− animal model, which lacks NK cells, these siblings demonstrate an expansion of NK cells, particularly the CD56bright subset, and a lack of terminally differentiated NK cells. Thus, the early-onset autoimmunity and immunodeficiency are linked to functional deficits arising from altered IL-2Rβ expression and signaling in T and NK cells.
Uncertainty quantification in particle image velocimetry
Authors: Sciacchitano A
Published: April 2019

Particle image velocimetry (PIV) has become the chief experimental technique for velocity field measurements in fluid flows. The technique yields quantitative visualizations of the instantaneous flow patterns, which are typically used to support the development of phenomenological models for complex flows or for validation of numerical simulations. However, due to the complex relationship between measurement errors and experimental parameters, the quantification of the PIV uncertainty is far from being a trivial task and has often relied upon subjective considerations. Recognizing the importance of methodologies for the objective and reliable uncertainty quantification (UQ) of experimental data, several PIV-UQ approaches have been proposed in recent years that aim at the determination of objective uncertainty bounds in PIV measurements.

This topical review on PIV uncertainty quantification aims to provide the reader with an overview of error sources in PIV measurements and to inform them of the most up-to-date approaches for PIV uncertainty quantification and propagation. The paper first introduces the general definitions and classifications of measurement errors and uncertainties, following the guidelines of the International Organization for Standards (ISO) and of renowned books on the topic. Details on the main PIV error sources are given, considering the entire measurement chain from timing and synchronization of the data acquisition system, to illumination, mechanical properties of the tracer particles, imaging of those, analysis of the particle motion, data validation and reduction. The focus is on planar PIV experiments for the measurement of two- or three-component velocity fields.

Approaches for the quantification of the uncertainty of PIV data are discussed. Those are divided into a-priori UQ approaches, which provide a general figure for the uncertainty of PIV measurements, and a-posteriori UQ approaches, which are data-based and aim at quantifying the uncertainty of specific sets of data. The findings of a-priori PIV-UQ based on theoretical modelling of the measurement chain as well as on numerical or experimental assessments are discussed. The most up-to-date approaches for a-posteriori PIV-UQ are introduced, highlighting their capabilities and limitations.

As many PIV experiments aim at determining flow properties derived from the velocity fields (e.g. vorticity, time-average velocity, Reynolds stresses, pressure), the topic of PIV uncertainty propagation is tackled considering the recent investigations based on Taylor series and Monte Carlo methods. Finally, the uncertainty quantification of 3D velocity measurements by volumetric approaches (tomographic PIV and Lagrangian particle tracking) is discussed.
Reaching supercritical field strengths with intense lasers
Authors: Blackburn T G , Ilderton A , Marklund M , Ridgers C P
Published: April 2019

It is conjectured that all perturbative approaches to quantum electrodynamics (QED) break down in the collision of a high-energy electron beam with an intense laser, when the laser fields are boosted to ‘supercritical’ strengths far greater than the critical field of QED. As field strengths increase toward this regime, cascades of photon emission and electron–positron pair creation are expected, as well as the onset of substantial radiative corrections. Here we identify the important role played by the collision angle in mitigating energy losses to photon emission that would otherwise prevent the electrons reaching the supercritical regime. We show that a collision between an electron beam with energy in the tens of GeV and a laser pulse of intensity

10

24

W

cm

−
2

at oblique, or even normal, incidence is a viable platform for studying the breakdown of perturbative strong-field QED. Our results have implications for the design of near-term experiments as they predict that certain quantum effects are enhanced at oblique incidence.
Geometric randomization of real networks with prescribed degree sequence
Authors: Starnini Michele , Ortiz Elisenda , Serrano M Ángeles
Published: April 2019

We introduce a model for the randomization of complex networks with geometric structure. The geometric randomization (GR) model assumes a homogeneous distribution of the nodes in a hidden similarity space and uses rewirings of the links to find configurations that maximize a connection probability akin to that of the popularity-similarity geometric network models. The rewiring preserves exactly the original degree sequence, thus preventing fluctuations in the degree cutoff. The GR model is manifestly simple as it relies upon a single free parameter controlling the clustering of the rewired network, and it does not require the explicit estimation of hidden degree variables. We demonstrate the applicability of GR by implementing it as a null model for the analysis of community structure. As a result, we find that geometric and topological communities detected in real networks are consistent, while topological communities are also detected in randomized counterparts as an effect of structural constraints.
Agency Theory in Business and Management Research
Authors: Payne G. Tyge , Petrenko Oleg V.
Published: April 2019

Agency theory is one the most prominent theoretical perspectives utilized in business and management research. Agency theory argues—using fundamental assumptions that agents are: (a) self-interested, (b) boundedly rational, and (c) different from principals in their goals and risk-taking preferences—that a problem occurs when one party (a principal) employs another (an agent) to make decisions and act in their stead. Essentially, the value of a principal-agent relationship is not optimized because the two contracted parties may have different interests and information is asymmetric (not equal). Agency costs are the result of principal and agent conflicts of interest and disagreements regarding actions that are taken. As such, monitoring and incentive-alignment systems are used to curb costs associated with opportunist behavior.

Agency theory is commonly utilized to understand and explain corporate governance phenomena, including executive incentive alignment, board monitoring, and control of top managers; this strand of the literature is founded in economics and represents the bulk of the research in business and management. However, other important principal-agent relationships are commonly seen in business and society, such as with politicians/voters, brokers/investors, and lawyers/clients, and have benefited from the vast stream of research that has explored the principal-agent relationship in various forms and contexts. Also, alternative theoretical perspectives have emerged to accommodate variations of the principal-agent relationship. Namely, principal-principal agency, behavioral agency, and stewardship theories are prominent alternative theories that challenge, expand, or relax the basic assumptions of the classic theory to extend our understanding of important relationships and mechanisms in business and management.