bluuebunny/crossref_metadata_2025 huggingface dataset:
Helicity Dynamics, Inverse, and Bidirectional Cascades in Fluid and Magnetohydrodynamic Turbulence: A Brief Review
Authors: Pouquet A. , Rosenberg D. , Stawarz J.E. , Marino R.
Published: February 2019

We briefly review helicity dynamics, inverse and bidirectional cascades in fluid and magnetohydrodynamic (MHD) turbulence, with an emphasis on the latter. The energy of a turbulent system, an invariant in the nondissipative case, is transferred to small scales through nonlinear mode coupling. Fifty years ago, it was realized that, for a two‐dimensional fluid, energy cascades instead to larger scales and so does magnetic excitation in MHD. However, evidence obtained recently indicates that, in fact, for a range of governing parameters, there are systems for which their ideal invariants can be transferred, with constant fluxes, to both the large scales and the small scales, as for MHD or rotating stratified flows, in the latter case including quasi‐geostrophic forcing. Such bidirectional, split, cascades directly affect the rate at which mixing and dissipation occur in these flows in which nonlinear eddies interact with fast waves with anisotropic dispersion laws, due, for example, to imposed rotation, stratification, or uniform magnetic fields. The directions of cascades can be obtained in some cases through the use of phenomenological arguments, one of which we derive here following classical lines in the case of the inverse magnetic helicity cascade in electron MHD. With more highly resolved data sets stemming from large laboratory experiments, high‐performance computing, and in situ satellite observations, machine learning tools are bringing novel perspectives to turbulence research. Such algorithms help devise new explicit subgrid‐scale parameterizations, which in turn may lead to enhanced physical insight, including in the future in the case of these new bidirectional cascades.
Atmospheric Circulation Response to Anomalous Siberian Forcing in October 2016 and its Long‐Range Predictability
Authors: Tyrrell Nicholas L. , Karpechko Alexey Yu. , Uotila Petteri , Vihma Timo
Published: February 2019

The warm Arctic‐cold continent pattern was of record strength in October 2016, providing the opportunity to test its proposed influence on large‐scale atmospheric circulation. We find a record weak polar stratospheric vortex and negative North Atlantic Oscillation in November–December 2016 and link them to increased planetary wave generation associated with cold Siberian anomalies followed by troposphere‐stratosphere dynamical coupling. At the same time the warm Arctic anomalies, in particular those over the Barents‐Kara Seas, do not appear to play an important role in forcing the atmospheric circulation. Long‐range forecasts initialized on 1 October 2016 reproduced both the weak polar vortex and negative North Atlantic Oscillation, as well as their link with the Siberian temperatures. Our results support the stratospheric pathway for atmospheric circulation forcing associated with Siberian surface anomalies and uncover a source of skill for subseasonal forecasts from October to December.
Hemispheric Asymmetry of the Premidnight Aurora Associated With the Dawn‐Dusk Component of the Interplanetary Magnetic Field
Authors: Liou K. , Mitchell E. J.
Published: February 2019

It has been known for decades that the nightside aurora in the Northern Hemisphere (NH) tends to be brighter when the interplanetary magnetic field (IMF) measured at Earth has a dawnward (negative y) component compared to a duskward (positive y) component. This asymmetric response to the polarity of IMF By has been explained by an interhemispheric current flowing out of the NH due to a nonuniform “penetration” of IMF By onto the magnetotail. If such a hypothesis is correct, it should predict a brighter aurora in the nightside Southern Hemisphere (SH) for positive IMF By than negative IMF By. Here we investigate this hypothesis using Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics/Global Ultraviolet Imager data. The present study not only reproduces the result previously found in NH but also shows an opposite change to its Northern Hemispheric counterpart in SH in response to the different IMF By polarity. When comparing north to south, for negative IMF By, the premidnight auroral energy flux is greater in NH than that in SH. The result becomes opposite for positive IMF By. This result is consistent with the hypothesis of the existence of an interhemispheric field‐aligned current.
A Theory of Effective Microbial Substrate Affinity Parameters in Variably Saturated Soils and an Example Application to Aerobic Soil Heterotrophic Respiration
Authors: Tang Jinyun , Riley William J.
Published: February 2019

Affinity parameters are essential for substrate kinetics‐based modeling of soil biogeochemistry. These parameters were originally defined for well‐mixed aqueous solutions to represent enzyme substrate binding. For variably saturated soils, they are often calibrated and highly uncertain. Here we develop a predictive theory of effective substrate affinity parameters to account for other processes that affect microbial substrate acquisition, so that the substrate kinetics for well‐mixed aqueous solutions can be similarly applied to variably saturated soils. The theory is based on an analytical approximation of how diffusive substrates are intercepted by soil microbial cells and integrates microbial characteristics, microsite structure, and soil physical properties. The predicted effective substrate affinity thus closely integrates the physical substrate limitation in soils with the intrinsic substrate affinity parameter. The theory predicts that, as moisture changes, the effective diffusive substrate delivery rates vary by orders of magnitude, resulting in highly variable effective affinity parameters for substrates like oxygen, methane, and nonvolatile solutes. As an example, we apply the theory with three substrate kinetics to aerobic soil incubations. Our models accurately reproduced observations of 32 soil incubations in four soil classes, demonstrating that the soil moisture versus respiration relationship varies with maximum respiration rate, soil texture, soil carbon content, and microbial biomass. This example suggests that the traditional use of a single static multiplicative function to parameterize how soil respiration depends on moisture is inappropriate. Because of its capability to integrate microbial traits and soil physical properties, our theory will help develop more robust soil biogeochemistry models.
The Power of Environmental Observatories for Advancing Multidisciplinary Research, Outreach, and Decision Support: The Case of the Minnesota River Basin
Authors: Gran K. B. , Dolph C. , Baker A. , Bevis M. , Cho S. J. , Czuba J. A. , Dalzell B. , Danesh‐Yazdi M. , Hansen A. T. , Kelly S. , Lang Z. , Schwenk J. , Belmont P. , Finlay J. C. , Kumar P. , Rabotyagov S. , Roehrig G. , Wilcock P. , Foufoula‐Georgiou E.
Published: February 2019

Observatory‐scale data collection efforts allow unprecedented opportunities for integrative, multidisciplinary investigations in large, complex watersheds, which can affect management decisions and policy. Through the National Science Foundation‐funded REACH (REsilience under Accelerated CHange) project, in collaboration with the Intensively Managed Landscapes‐Critical Zone Observatory, we have collected a series of multidisciplinary data sets throughout the Minnesota River Basin in south‐central Minnesota, USA, a 43,400‐km2 tributary to the Upper Mississippi River. Postglacial incision within the Minnesota River valley created an erosional landscape highly responsive to hydrologic change, allowing for transdisciplinary research into the complex cascade of environmental changes that occur due to hydrology and land use alterations from intensive agricultural management and climate change. Data sets collected include water chemistry and biogeochemical data, geochemical fingerprinting of major sediment sources, high‐resolution monitoring of river bluff erosion, and repeat channel cross‐sectional and bathymetry data following major floods. The data collection efforts led to development of a series of integrative reduced complexity models that provide deeper insight into how water, sediment, and nutrients route and transform through a large channel network and respond to change. These models represent the culmination of efforts to integrate interdisciplinary data sets and science to gain new insights into watershed‐scale processes in order to advance management and decision making. The purpose of this paper is to present a synthesis of the data sets and models, disseminate them to the community for further research, and identify mechanisms used to expand the temporal and spatial extent of short‐term observatory‐scale data collection efforts.
A Vision for Adapting at the Pace of Socioenvironmental Change
Authors: Wee Brian , Pi�a Aaron
Published: February 2019

The Resilience Genome Initiative will empower a cadre of transdisciplinary resilience engineers to adopt and continuously develop climate adaptation solutions.
Interactions in self-assembled microbial communities saturate with diversity
Authors: Yu Xiaoqian , Polz Martin F , Alm Eric J
Published: February 2019

How the diversity of organisms competing for or sharing resources influences community function is an important question in ecology but has rarely been explored in natural microbial communities. These generally contain large numbers of species making it difficult to disentangle how the effects of different interactions scale with diversity. Here, we show that changing diversity affects measures of community function in relatively simple communities but that increasing richness beyond a threshold has little detectable effect. We generated self-assembled communities with a wide range of diversity by growth of cells from serially diluted seawater on brown algal leachate. We subsequently isolated the most abundant taxa from these communities via dilution-to-extinction in order to compare productivity functions of the entire community to those of individual taxa. To parse the effect of different types of organismal interactions, we defined relative total function (RTF) as an index for positive or negative effects of diversity on community function. Our analysis identified three overall regimes with increasing diversity. At low richness (<12 taxa), positive and negative effects of interactions were both weak, while at moderate richness (12–26 taxa), community resource uptake increased but the carbon use efficiency decreased. Finally, beyond 26 taxa, the effect of interactions on community function saturated and further diversity increases did not affect community function. Although more diverse communities had overall greater access to resources, on average individual taxa within these communities had lower resource availability and reduced carbon use efficiency. Our results thus suggest competition and complementation simultaneously increase with diversity but both saturate at a threshold.
Carbon nitride photocatalyzes regioselective aminium radical addition to the carbonyl bond and yields N-fused pyrroles
Authors: Kurpil Bogdan , Otte Katharina , Mishchenko Artem , Lamagni Paolo , Lipiński Wojciech , Lock Nina , Antonietti Markus , Savateev Aleksandr
Published: February 2019

Addition of N-centered radicals to C=C bonds or insertion into C–H bonds is well represented in the literature. These reactions have a tremendous significance, because they afford polyfunctionalized organic molecules. Despite the tetrahydroisoquinoline (THIQ) moiety widely occurring in natural biologically active compounds, N-unsubstituted THIQs as a source of N-centered radicals are not studied. Herein, we report a photocatalytic reaction between tetrahydroisoquinoline and chalcones that gives N-fused pyrroles—1,3-disubstituted-5,6-dihydropyrrolo[2,1-a]isoquinolines (DHPIQ). The mechanism includes at least two photocatalytic events in one pot: (1) C–N bond formation; (2) C–C bond formation. In this process potassium poly(heptazine imide) is used as a visible light active heterogeneous and recyclable photocatalyst. Fifteen N-fused pyrroles are reported with 65–90% isolated yield. DHPIQs are characterized by UV–vis and fluorescence spectroscopy, while the fluorescence quantum efficiency of fluorinated DHPIQs reaches 24%.
Societal decisions about climate mitigation will have dramatic impacts on eutrophication in the 21st century
Authors: Sinha E. , Michalak A. M. , Calvin K. V. , Lawrence P. J.
Published: February 2019

Excessive nitrogen runoff leads to degraded water quality, harming human and ecosystem health. We examine the impact of changes in land use and land management for six combinations of socioeconomic pathways and climate outcomes, and find that societal choices will substantially impact riverine total nitrogen loading (+54% to −7%) for the continental United States by the end of the century. Regional impacts will be even larger. Increased loading is possible for both high emission and low emission pathways, due to increased food and biofuel demand, respectively. Some pathways, however, suggest that limiting climate change and eutrophication can be achieved concurrently. Precipitation changes will further exacerbate loading, resulting in a net increase of 1 to 68%. Globally, increases in cropland area and agricultural intensification will likely impact vast portions of Asia. Societal and climate trends must therefore both be considered in designing strategies for managing inland and coastal water quality.
Contrast and luminance adaptation alter neuronal coding and perception of stimulus orientation
Authors: Ghodrati Masoud , Zavitz Elizabeth , Rosa Marcello G. P. , Price Nicholas S. C.
Published: February 2019

Sensory systems face a barrage of stimulation that continually changes along multiple dimensions. These simultaneous changes create a formidable problem for the nervous system, as neurons must dynamically encode each stimulus dimension, despite changes in other dimensions. Here, we measured how neurons in visual cortex encode orientation following changes in luminance and contrast, which are critical for visual processing, but nuisance variables in the context of orientation coding. Using information theoretic analysis and population decoding approaches, we find that orientation discriminability is luminance and contrast dependent, changing over time due to firing rate adaptation. We also show that orientation discrimination in human observers changes during adaptation, in a manner consistent with the neuronal data. Our results suggest that adaptation does not maintain information rates per se, but instead acts to keep sensory systems operating within the limited dynamic range afforded by spiking activity, despite a wide range of possible inputs.
Author Correction: HYSOGs250m, global gridded hydrologic soil groups for curve-number-based runoff modeling
Authors: Ross C. Wade , Prihodko Lara , Anchang Julius , Kumar Sanath , Ji Wenjie , Hanan Niall P.
Published: February 2019

The original version of this Data Descriptor incorrectly referenced the “United Nations (UN) Food and Agriculture Organization (FAO) soilGrids250m system”. This has been corrected to “SoilGrids predictions” throughout the text in both the HTML and PDF versions.
Publisher Correction: Interspecific formation of the antimicrobial volatile schleiferon
Authors: Kai Marco , Effmert Uta , Lemfack Marie Chantal , Piechulla Birgit
Published: February 2019

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Early responses given distinct tactics to infection of Peronophythora litchii in susceptible and resistant litchi cultivar
Authors: Sun Jinhua , Cao Lulu , Li Huanling , Wang Guo , Wang Shujun , Li Fang , Zou Xiaoxiao , Wang Jiabao
Published: February 2019

Litchi downy blight, a destructive litchi disease caused by Peronophythora litchii, is controlled by intensive fungicide applying. Sources of resistance are used in conventional breeding approaches, but the mechanism is not well understood. Follow-up six years investigation, ‘Guiwei’ and ‘Heiye’ displayed stable susceptible and resistant against to P. litchii, respectively. After 72 hour inoculation, ‘Heiye’ showed few disease spots, while ‘Guiwei’ appeared brown and covered with white sporangia. Germination of sporangia and growth of mycelium in ‘Guiwei’ is more quickly than in ‘Heiye’. Transcript levels were measured at 6, 24, and 48 hour post-inoculation. ‘Oxidation-reduction process’ was dramatically enhanced in ‘Heiye’, which could promote its resistance to pathogen infection. A small ratio (3.78%) of common DEGs indicates that resistant and susceptible cultivars take different strategies to defense against P. litchii. At early infection stage, ‘Heiye’ induced a larger number of genes, including seven receptor-like kinases, which quickly recognized attack of pathogen and led to a rapidly resistance by regulation of degradation of proteasome, transcription factors, and cell wall remodeling. The early DGEs were exiguous in ‘Guiwei’, suggesting a weak response. Once the infection was successful, the resistance was repressed by down-regulated genes involved in phenylpropanoid metabolism, ET biosynthesis and signaling conduction in ‘Guiwei’. In conclusion, quickly recognition and early responses to pathogen, as well as minimal pathogen development and basal expression of resistance-related genes, were correlated with a high level of resistance in ‘Heiye’, while susceptible ‘Guiwei’ suffered massive infection due to lagging response and repressed signal transduction.
Recurrence Rate and Relevant Associated Factors of Stroke among Patients with Small Artery Occlusion in Northern China
Authors: Zhang Ying , Guan Yalin , Zhang Yajing , Liu Shuling , Zheng Man , Wang Min , Su Wenhua , Wu Hao
Published: February 2019

Small artery occlusion (SAO) is responsible for 31.3% of all ischemic strokes in China. However, reports regarding the recurrence rate of SAO in China are rare. We aimed to assess the recurrence rate and factors associated with SAO in China. All consecutive patients with SAO hospitalized at Tianjin Huanhu Hospital from 2005 to 2014 were recruited. We assessed the association between stroke subtype, severity, and disease history with recurrence at 3, 12, and 36 months of onset using multivariate logistic regression analysis. A total of 2,524 SAO patients were included in this study, including 1696 (67.2%) men and 828 (32.8%) women. The recurrence rates were 3.1% at 3 months, 12.7% at 12 months, and 36.5% at 36 months. Compared with women, men had a higher risk of recurrence at 3 months after SAO (P = 0.003). Old age and severity of stroke were also associated with a higher risk of recurrence (P < 0.05). Patients with an elevated C-reactive protein had a higher risk of recurrence at 12 months (P = 0.003). On the other hand, the risk of recurrence at 12 months was 39% lower in patients who consumed alcohol than in those who did not (P = 0.037). Hypertension, atrial fibrillation, and obesity were independent risk factors of recurrence at 36 months. These findings suggest that modification of risk factors in patients with SAO, particularly men, is essential for reducing the rate of recurrence and the overall burden of stroke in China.
Metal- and solvent-free synthesis of amides using substitute formamides as an amino source under mild conditions
Authors: Zhang Feng , Li Lesong , Zhang Jingyu , Gong Hang
Published: February 2019

This study described an efficient and practical approach for amide synthesis. The reaction was conducted under metal- and solvent-free conditions at a mild temperature (40 °C) in air, and readily available formamides were used as an amino source. This reaction can be easily upgraded to the gram level with an excellent yield.
Experimental Investigation of Damage Formation in Planar Fibrous Networks During Stretching
Authors: Sipos Evelin , Kaneko Tatsuo , Zrinyi Miklós
Published: February 2019

This paper presents the results of unidirectional strain-controlled experiments on fibrous electrospun networks used to study damage formation during elongation. The experimental loading curve shows a symmetrical parabolic type dependence at large scale and saw tooth-like force−extension behaviour at small scale. The damage formation was quantified by determining the number and the magnitude of abrupt force drops. The experiments evidenced that damage evolution is a consequence of strain induced random events. The frequency distribution of the number of damages as well as the magnitude of rupture force were represented by histograms. The results of the present study provide a better insight into damage tolerance and complex nonlinear tensile properties of electrospun networks. In addition, it could suggest a possible probabilistic approach to the fiber bundle model which has mainly motivated this study.
Alignment-free similarity analysis for protein sequences based on fuzzy integral
Authors: Saw Ajay Kumar , Tripathy Binod Chandra , Nandi Soumyadeep
Published: February 2019

Sequence comparison is an essential part of modern molecular biology research. In this study, we estimated the parameters of Markov chain by considering the frequencies of occurrence of the all possible amino acid pairs from each alignment-free protein sequence. These estimated Markov chain parameters were used to calculate similarity between two protein sequences based on a fuzzy integral algorithm. For validation, our result was compared with both alignment-based (ClustalW) and alignment-free methods on six benchmark datasets. The results indicate that our developed algorithm has a better clustering performance for protein sequence comparison.
90Y-NM600 targeted radionuclide therapy induces immunologic memory in syngeneic models of T-cell Non-Hodgkin’s Lymphoma
Authors: Hernandez Reinier , Walker Kirsti L. , Grudzinski Joseph J. , Aluicio-Sarduy Eduardo , Patel Ravi , Zahm Christopher D. , Pinchuk Anatoly N. , Massey Christopher F. , Bitton Ariana N. , Brown Ryan J. , Sondel Paul M. , Morris Zachary S. , Engle Jonathan W. , Capitini Christian M. , Weichert Jamey P.
Published: February 2019

Finding improved therapeutic strategies against T-cell Non-Hodgkin’s Lymphoma (NHL) remains an unmet clinical need. We implemented a theranostic approach employing a tumor-targeting alkylphosphocholine (NM600) radiolabeled with 86Y for positron emission tomography (PET) imaging and 90Y for targeted radionuclide therapy (TRT) of T-cell NHL. PET imaging and biodistribution performed in mouse models of T-cell NHL showed in vivo selective tumor uptake and retention of 86Y-NM600. An initial toxicity assessment examining complete blood counts, blood chemistry, and histopathology of major organs established 90Y-NM600 safety. Mice bearing T-cell NHL tumors treated with 90Y-NM600 experienced tumor growth inhibition, extended survival, and a high degree of cure with immune memory toward tumor reestablishment. 90Y-NM600 treatment was also effective against disseminated tumors, improving survival and cure rates. Finally, we observed a key role for the adaptive immune system in potentiating a durable anti-tumor response to TRT, especially in the presence of microscopic disease.
Selective prebiotic synthesis of phosphoroaminonitriles and aminothioamides in neutral water
Authors: Ashe Kathryn , Fernández-García Christian , Corpinot Merina K. , Coggins Adam J. , Bučar Dejan-Krešimir , Powner Matthew W.
Published: February 2019

The central and conserved role of peptides in extant biology suggests that they played an important role during the origins of life. Strecker amino acid synthesis appears to be prebiotic, but the high pKaH of ammonia (pKaH = 9.2) necessitates high pH reaction conditions to realise efficient synthesis, which places difficult environmental constraints on prebiotic amino acid synthesis. Here we demonstrate that diamidophosphate reacts efficiently with simple aldehydes and hydrogen cyanide in water at neutral pH to afford N-phosphoro-aminonitriles. N-Phosphoro-aminonitrile synthesis is highly selective for aldehydes; ketones give poor conversion. N-Phosphoro-aminonitriles react with hydrogen sulfide at neutral pH to furnish aminothioamides. The high yield (73%–Quant.) of N-phosphoro-aminonitriles at neutral pH, and their selective transformations, may provide new insights into prebiotic amino acid synthesis and activation.
Harnessing ferroelectric domains for negative capacitance
Authors: Luk’yanchuk I. , Tikhonov Y. , Sené A. , Razumnaya A. , Vinokur V. M.
Published: February 2019

A pressing quest for overcoming Boltzmann tyranny in low-power nanoscale electronics ignited an extensive search for the devices possessing the negative circuit constants. The emergent concept of the ferroelectric-based negative capacitance triggered then the explosive activity in the field. However, most of the research addressed transient negative capacitance, leaving the basic question of the existence of the steady-state negative capacitance unresolved. Here, we show that the ferroelectric nanodot capacitor hosts a stable two-domain state realizing the static reversible negative capacitance device thus opening routes for the extensive use of the negative capacitance in domain wall-based nanoelectronics.
Infrared photodissociation spectroscopic investigation of TMO(CO)n+(TM = Sc, Y, La): testing the 18-electron rule
Authors: Chen Yinjuan , Xin Ke , Jin Jiaye , Li Wei , Wang Qiang , Wang Xuefeng , Wang Guanjun
Published: February 2019

Gaseous TMO(CO)n+(TM = Sc, Y, La) complex cations preparedvialaser vaporization were mass-selected and studied by infrared photodissociation spectroscopy in the C–O stretching frequency region.
Self-assembled colloidal arrays for structural color
Authors: Liu Panmiao , Bai Ling , Yang Jianjun , Gu Hongcheng , Zhong Qifeng , Xie Zhuoying , Gu Zhongze
Published: February 2019

This review focuses on the structural color induced by colloidal assembly at the generation, modulation, and application stages, along with the authors' perspectives on the challenges and future opportunities.
Realization and direct observation of five normal and parametric modes in silicon nanowire resonators by in situ transmission electron microscopy
Authors: Hsia Feng-Chun , Tang Dai-Ming , Jevasuwan Wipakorn , Fukata Naoki , Zhou Xin , Mitome Masanori , Bando Yoshio , Nordling Torbjörn E. M. , Golberg Dmitri
Published: February 2019

In situ TEM observation of the 5th order normal and parametric resonances for precise evaluation of Si NWs' elastic moduli.
Crystal structure, spectroscopic, DNA binding studies and DFT calculations of a Zn(ii) complex
Authors: Mondal Satyajit , Chakraborty Moumita , Mondal Antu , Pakhira Bholanath , Mukhopadhyay Subhra Kanti , Banik Avishek , Sengupta Swaraj , Chattopadhyay Shyamal Kumar
Published: February 2019

A highly fluorescent Zn(ii) complex and its DNA-binding and bio-imaging applications are reported.
Design of the NnH3n+1+series of “non-metallic” superalkali cations
Authors: Srivastava Ambrish Kumar
Published: February 2019

A new series of non-metallic superalkali cations, NnH3n+1+by using ammonium (NH4+) cations, possessing vertical electron affinity (EAv), 4.39 eV forn= 1 to 2.39 eV forn= 5 has been proposed. This series can be continued for obtaining new superalkali cations, for instance N9H28+with an EAvof 1.84 eV. The EAvof NnH3n+1+cations is governed by the electron localization on the central N-atom. The EAvof NnH3n+1+cations decays exponentially with an increase inn.
Plant growth promoting N-alkyltropinium bromides enhance seed germination, biomass accumulation and photosynthesis parameters of maize (Zea mays)
Authors: Parus Anna , Framski Grzegorz , Rypniewski Wojciech , Panasiewicz Katarzyna , Szulc Piotr , Myszka Kamila , Zgoła-Grześkowiak Agnieszka , Ławniczak Łukasz , Chrzanowski Łukasz
Published: February 2019

N-Alkyltropinium bromides were synthesized and characterized as novel plant-growth promoting agents.
A new strategy for electrochemical fabrication of manganese dioxide coatings based on silica nanoparticles deposited on titanium fibers for selective and highly efficient solid-phase microextraction
Authors: Wang Ziyi , Wang Feifei , Zhang Rong , Wang Zuo , Du Xinzhen
Published: February 2019

Electrochemical fabrication of a novel Ti@TiO2@SiO2NPs@MnO2/PPyNPs fiber and its application in solid-phase microextraction coupled to HPLC-UV.
To heat or not to heat: a study of the performances of iron carbide nanoparticles in magnetic heating
Authors: Asensio Juan M. , Marbaix Julien , Mille Nicolas , Lacroix Lise-Marie , Soulantica Katerina , Fazzini Pier-Francesco , Carrey Julian , Chaudret Bruno
Published: February 2019

This study shows why FeC NPs of similar structures and static magnetic properties display radically different heating power (SAR from 0 to 2 kW g−1).
An ensemble variable selection method for vibrational spectroscopic data analysis
Authors: Zhang Jixiong , Yan Hong , Xiong Yanmei , Li Qianqian , Min Shungeng
Published: February 2019

A new ensemble method for wavelength selection.
Development of a HPLC-FL method to determine benzaldehyde after derivatization with N-acetylhydrazine acridone and its application for determination of semicarbazide-sensitive amine oxidase activity in human serum
Authors: Dong Xiuli , Tang Jiayuan , Ren Yan , Chen Xiangming
Published: February 2019

A highly sensitive HPLC-FL method to determine semicarbazide-sensitive amine oxidase activity was developed utilizing AHAD as the novel fluorescence labeling reagent.
A ternary cobalt–molybdenum–vanadium layered double hydroxide nanosheet array as an efficient bifunctional electrocatalyst for overall water splitting
Authors: Bao Jian , Wang Zhaolong , Xie Junfeng , Xu Li , Lei Fengcai , Guan Meili , Zhao Yan , Huang Yunpeng , Li Huaming
Published: February 2019

A ternary cobalt–molybdenum–vanadium layered double hydroxide nanosheet array was designed as an efficient bifunctional electrocatalyst for overall water splitting.
Mode-specific excited-state dynamics of N-methylpyrrole
Authors: Woo Kyung Chul , Kim Sang Kyu
Published: February 2019

A picosecond time-resolved dynamics study unravels the photo-physical properties of N-methylpyrrole in excited-states in a mode-specific way.
A novel LEuH/PVA luminescent hydrogel with ammonia response and self-recovery luminescence behavior
Authors: Wang Yuan , Zhang Wenjun , Li Jinglin , Fu Jie
Published: February 2019

A dual-use hydrogel for ammonia sensing in gas or liquid exhibits reversibility of luminescence on/off switching.
The role of electron-attracting substituents and molecular stacking motifs in the charge transport of tetraazapyrene derivatives
Authors: Shi Ya-Rui , Wei Hui-Ling , Liu Yu-Fang
Published: February 2019

The frontier orbital energies, charge transport properties and photophysical properties of TAPy derivatives were theoretically investigated by means of DFT.
Quasi-layer Co2P-polarized Cu3P nanocomposites with enhanced intrinsic interfacial charge transfer for efficient overall water splitting
Authors: Liu Liangbin , Ge Lei , Sun Yuyang , Jiang Binbin , Cheng Yafei , Xu Lai , Liao Fan , Kang Zhenhui , Shao Mingwang
Published: February 2019

Multi-interface Cu3P–Co2P nanocomposites are obtained from the combination of the quasi-layer structure of Co2P and the polarized plane of Cu3P, which show increased catalytic activity for water splitting.
Enhanced intrinsic saturation magnetization of ZnxCo1−xFe2O4 nanocrystallites with metastable spinel inversion
Authors: Andersen Henrik Lyder , Granados-Miralles Cecilia , Saura-Múzquiz Matilde , Stingaciu Marian , Larsen Jacob , Søndergaard-Pedersen Frederik , Ahlburg Jakob Voldum , Keller Lukas , Frandsen Cathrine , Christensen Mogens
Published: February 2019

Meticulous structural characterization of ZnxCo1−xFe2O4 nanocrystallites reveals a metastable cation distribution, which causes an enhancement of the intrinsic saturation magnetization.
Visible light photocatalytic acyldifluoroalkylation of unactivated alkenes for the direct synthesis of gem-difluorinated ketones
Authors: Zhou Yulu , Xiong Zhimin , Qiu Jiayan , Kong Lichun , Zhu Gangguo
Published: February 2019

A photoredox-catalyzed alkene acyldifluoroalkylation with difluoroacetic acids for the direct synthesis of gem-difluorinated cyclic ketones is developed.
Electrophilic activation of nitroalkanes in efficient synthesis of 1,3,4-oxadiazoles
Authors: Aksenov Alexander V. , Khamraev Vladislav , Aksenov Nicolai A. , Kirilov Nikita K. , Domenyuk Dmitriy A. , Zelensky Vladimir A. , Rubin Michael
Published: February 2019

A novel methodology for chemoselective preparation of non-symmetric 1,3,4-oxadiazolesviaPPA-assisted activation of nitroalkanes towards nucleophilic attack with acylhydrazides is developed.
(Z)-α-Boryl-crotylboron reagents via Z-selective alkene isomerization and application to stereoselective syntheses of (E)-δ-boryl-syn-homoallylic alcohols
Authors: Gao Shang , Chen Jichao , Chen Ming
Published: February 2019

Stereoselective synthesis of (Z)-α-boryl-crotylboronate is developed.
Fault‐tolerant consensus control of second‐order multi‐agent system based on sliding mode control theory
Authors: Xu Mengyang , Yang Pu , Huang Yi , Shu Qibao , Wang Yuxia
Published: February 2019

This paper mainly investigates the consensus implementation problem of multi‐wheeled mobile robot system in the case of actuator additive fault and external disturbance. By constructing the traditional sliding surface, the adaptive law about the upper bound estimation of actuator fault is designed and a fault‐tolerant consensus control algorithm for the second‐order multi‐agent system (MAS) in the case of actuator additive fault is proposed. Subsequently, the theoretical rationality of this algorithm is proved by Lyapunov‐related theory. In addition, the authors also propose a solution for the chattering problem of the traditional sliding surface by adjusting the adaptive law of the upper‐bound estimation of faults. Finally, the authors use a multi‐wheeled mobile robot system to verify the effectiveness of fault‐tolerant consensus algorithm proposed by this paper.
Galactic H I supershells: kinetic energies and possible origin
Authors: Suad L. A. , Caiafa C. F. , Cichowolski S. , Arnal E. M.
Published: February 2019

Context. The Milky Way, when viewed in the neutral hydrogen line emission, presents large structures called Galactic supershells (GSs). The origin of these structures is still a subject of debate. The most common scenario invoked is the combined action of strong winds from massive stars and their subsequent explosion as supernova.

Aims. The aim of this work is to determine the origin of 490 GSs that belong to the catalogue of H I supershell candidates in the outer part of the Galaxy.

Methods. To know the physical processes that took place to create these expanding structures, it is necessary to determine their kinetic energies. To obtain all the GS masses, we developed and used an automatic algorithm, which was tested on 95 GSs whose masses were also estimated by hand.

Results. The estimated kinetic energies of the GSs vary from 1 × 1047 to 3.4 × 1051 erg. Considering an efficiency of 20% for the conversion of mechanical stellar wind energy into the kinetic energy of the GSs, the estimated values of the GS energies could be reached by stellar OB associations. For the GSs located at high Galactic latitudes, the possible mechanism for their creation could be attributed to collision with high velocity clouds (HVC). We have also analysed the distribution of GSs in the Galaxy, showing that at low Galactic latitudes, |b| < 2°, most of the structures in the third Galactic quadrant seem to be projected onto the Perseus Arm. The detection of GSs at very high distances from the Galactic centre may be attributed to diffuse gas associated with the circumgalactic medium of M31 and to intra-group gas in the Local Group filament.
Beeinflussung der equinen Mikrobiota durch Fütterung und
Probiotika: aktueller Stand der Forschung und rechtliche
Grundlagen
Authors: Langner Katharina , Vervuert Ingrid
Published: February 2019

Die Mikrobiota im Dickdarm des Pferdes ist ein komplexes Gefüge, das durch die
Fütterung stark beeinflusst werden kann. So führt beispielsweise die Fütterung
eines stärkereichen Kraftfutters zum Anstieg von Bakterien, die Stärke
fermentieren und Laktat produzieren, während sich die Anzahl der für die
Faserverdauung zuständigen zellulolytischen Bakterien reduziert. Zur Optimierung
der bakteriellen Mikrobiota werden vielfach Probiotika eingesetzt, um
beispielsweise den potenziell negativen Einfluss stärkereicher Rationen zu
minimieren. Für das Pferd sind in der Europäischen Union zurzeit lediglich
verschiedene Stämme der Hefe Saccharomyces cerevisiae (SC) als
Probiotikum zugelassen. In-vivo-Studien bei adulten Pferden konnten jedoch keine
eindeutigen Effekte einer SC-Supplementation nachweisen.
Stereoselective Total Synthesis of Macrolide Sch-725674 and C-7-epi-Sch-725674
Authors: Baikadi Karunakar , Talakokkula Anil , Narsaiah A.
Published: February 2019

The stereoselective total synthesis of Sch-725674 in 14 ­linear synthetic steps with 10.3% overall yield is described. The synthesis started from commercially available starting materials, d-ribose and (R)-benzyl glycidol. The key reactions involved CBS reduction, Julia–­Kocienski olefination, Horner–Wadsworth–Emmons reaction, and ­Shiina macrolactonization.
Effective antimicrobial resistance communication: the role of information design
Authors: Walker Sue
Published: February 2019

Getting the message across about the dangers of antimicrobial resistance (AMR) and how to prevent it is a global priority. This article discusses the role of information design in the effective communication of information about AMR, and suggests that the design process—user input, iteration and consideration of circumstances of use—is key to successful communication. To illustrate this, using material from the Otto and Marie Neurath Isotype Collection at the University of Reading, this article considers the work of Otto and Marie Neurath who developed the Isotype system for visual education in the 1920s. They collaborated with scientists, writers and illustrators to ensure that messages were both accurate and relevant for their intended audiences, so that people could make their own decisions based on factual explanation. Their use of pictograms and schematic illustrations, consistent use of colours to represent meaning, and carefully considered relationships between text and image provided a distinctive visual ‘look and feel’. The charts designed by the Neuraths to educate people about health included a series made in the 1930s for the US National Tuberculosis Association to explain the dangers of, and how to prevent TB. This article reviews how these charts were designed, including the designated role of the ‘transformer’ who worked to ensure that scientific facts were presented in an understandable form. The way of working and the verbal and graphic characteristics of the charts deserve serious consideration for effective communication of information about AMR today. Particularly relevant are the use of schematic images using scale and simplification to attract attention, the use of story-telling to engage people, not overwhelming readers with too much information, and using straightforward language. The article asserts that cross-disciplinary working is key to successful explanation about the dangers of AMR. It illustrates this with reference to a research project, influenced by the Isotype approach to public health communication, that brings together academics and practitioners in information design, architecture, ergonomics and human factors, and pharmacy in communicating information about AMR to people using community pharmacies.
Quantum shell effects in compressed mesoscopic system
Authors: Kuratov S. E. , Shidlovski D. S. , Blinnikov S. I.
Published: February 2019

This article demonstrates the nontrivial manifestation of quantum shell effects in a compressed mesoscopic system. It is shown that there are two spatial scales in the distribution of degenerate electrons in a spherical well. The first scale is the Fermi length ∼h/pF. By the quantum shell effect, the authors mean the existence of the new spatial scale, which is the order of the system size and much larger than the first scale. The theoretical analysis for the large amount of free electrons (N ≲ 109) in an infinite spherical well demonstrates what causes the appearance of the spatial nonuniformity and gives the analytical expression for the electron distribution function. These results are confirmed by a numerical summation of exact solutions for the electron wave functions in an infinite potential well. It is shown that an analogous effect for the spatial distribution of electrons exists in a compressed hydrogen gas bubble of submicron size (<0.1 μm). The numerical simulation of the electron distribution was carried out by the Density Functional Theory method. The consequence of this effect is the nontrivial dynamics of the compressible cold gas bubble. This system can be realized in the thermonuclear experiments. The limiting factors of the analyzed effect are considered: symmetry of the system, electron temperature, and curvature of the system boundary.
Review of the renewable energy outlook in Saudi Arabia
Authors: Al-Douri Y. , Waheeb S. A. , Voon C. H.
Published: February 2019

Currently, existing technologies of energy generation based on fossil fuels and production processes of crude oil usually accompanied by flaring of gases resulted in excessive CO2 emissions. Kingdom of Saudi Arabia (KSA) national oil consumption is increasing by 7% annually. If this growth rate continues, local demands will be doubled in a decade. This study has covered various renewable energy solutions such as solar thermal hybrid solutions, photovoltaic cells/arrays, and wind turbines. A selection of possible applications of sustainable buildings, wind farming, solar energy, and their futures are discussed. From the crisis viewpoint of energy and environment safety, architectural trends have shifted toward sustainability demands. Energy and ecology were impetus to improve the residents' life quality and health standards. The climate/building correlation has been established to observe the response between both of them. Five distinguished coastal locations in KSA have given the consideration for wind farms, where meteorological data have been recorded since 1970. In contrast to the hot and irksome weather, water misting systems are elaborated to settle a soothing atmosphere. The results are noticed for evaporation and robbing the excessive heat. It is known that health is dependent on clean and unpolluted air, and the pollution has a threat for public health everywhere. So, an induction of renewable energy future has been considered. Gas turbine technology is also discussed as it accounts for about half of the overall capability of the KSA's power generation. Temperature, humidity, and pressure conditions have been accounted as important factors that affect gas turbine performance to produce electricity. An outlook of domestic energy cost is also reviewed. Furthermore, this study has focused on the necessity of maintaining a green and clean environment as well as a climate of lowest dust content. “Reference prices” concept has been clearly comprehended and understood. The contradiction of real opportunities and marginal costs has been explained. An important issue regarding depletion of resources that are depleted exhaustible has been studied. This issue has been tackled and being showed from the starting point. Alternative solutions to provide new energy sources are assumed.
Electrostatic wave instability and soliton formation with non-thermal electrons in O-H plasma of ionosphere
Authors: Shan Shaukat Ali , Hassan Ibtehaj , Saleem H.
Published: February 2019

It is pointed out that the presence of non-thermal electrons and protons in oxygen plasma of the ionosphere plays a destructive role in the formation of electrostatic structures by nonlinear ion acoustic waves (IAWs). On the other hand, linear electrostatic perturbations at different IAW frequencies are excited by the field-aligned shear flow in oxygen-hydrogen plasma of the upper ionosphere, and non-thermal electrons cause an increase in the growth rate. The excitation of IAW and formation of solitary structures in the ionosphere are investigated at altitudes of 600 km and 1000 km in the auroral region.
Physics of picosecond pulse laser ablation
Authors: Keller Wesley J. , Shen Nan , Rubenchik Alexander M. , Ly Sonny , Negres Raluca , Raman Rajesh N. , Yoo Jae-Hyuck , Guss Gabe , Stolken James S. , Matthews Manyalibo J. , Bude Jeff D.
Published: February 2019

This study investigates the physical processes involved in picosecond pulse (20-28 ps FWHM) laser ablation of Al 6061, 316L stainless steel, and undoped crystalline Si (〈100〉) over a range of laser wavelength (355 nm and 1064 nm) and fluence (0.1-40 J/cm2). Experimental measurements of material ablation rate show enhanced removal at the 355 nm wavelength, primarily due to laser-plasma interaction (LPI) within the ablative plume that approaches an order of magnitude increase over the measured removal at 1064 nm. A transition in the ablation rate at 355 nm is identified around ∼10 J/cm2 above which the removal efficiency increases by a factor of two to three. Multi-physics radiation hydrodynamic simulations, considering LPI effects and utilizing a novel mixed-phase equation of state model, show that the transition in ablation efficiency is due to the onset of melt ejection through cavitation, where laser-driven shock heating sets the depth of melt penetration and the ensuing release wave from the ablation surface drives cavitation through the imposition of tensile strain within the melt. High-speed pump-probe imaging of the ejecta and ejecta collection studies, as well as scanning electron microscopy of the ablation craters, support the proposed cavitation mechanism in the higher fluence range. The ablation process is critically influenced by LPI effects and the thermophysical properties of the material.
Properties of laser-driven hard x-ray sources over a wide range of laser intensities
Authors: Borm Björn , Khaghani Dimitri , Neumayer Paul
Published: February 2019

We present measurements of the hard x-ray emission from targets irradiated at relativistic laser intensities, with the objective of comprehensively characterizing source properties relevant to x-ray radiography backlighting in high energy density experiments. Thin gold foil and tungsten wire targets were irradiated at peak laser intensities varying between 1018 and 1021 W/cm2, with laser pulse energies >100 J. We have measured the absolute x-ray yield in the spectral range between 20 and 200 keV, angularly resolved over a large range of emission angles with respect to the incident laser. In addition, we have determined the x-ray source sizes for the two target types in the direction both along and across the target. The results are compared with the predictions of a simple model for the hot electron propagation, x-ray generation, collisional stopping, and expansion cooling. Based on this model, our measurements allow extraction of the laser to hot electron conversion over the wide range of intensities covered by our experiment.