bluuebunny/crossref_metadata_2025 huggingface dataset:
Revealing Ammonia Quantification Minefield in Photo/Electrocatalysis
Authors: Zhao Yunxuan , Wu Fan , Miao Yingxuan , Zhou Chao , Xu Ning , Shi Run , Wu Li‐Zhu , Tang Junwang , Zhang Tierui
Published: August 2021

Photo/electrocatalytic ammonia synthesis has recently developed fast while the ammonia yields over state‐of‐the‐art photo/electrocatalysts are still very moderate. Such low concentration of synthesized NH3 brings about a challenge to the reliable quantification of the product in photo/electrocatalysis. Notably, we found that the quantitative detection of ammonia concentration below 0.2 ppm is error‐prone, which is likely the case happening in the majority of photo/electrocatalytic NH3 synthesis, thus arising concerns about the rationality and accuracy for low‐concentration ammonia quantification in these processes. Herein, we discuss the methodology used and analyze the reliability of various detection methods for the detection of trace ammonia in aqueous media. The challenges facing the detection of low concentration of ammonia in photo/electrocatalysis can be overcome by integration with multiple detection methods. According to the data presented, we also propose an effective criterion for precise quantification of ammonia, avoiding the unreasonable comparisons in photo/electrocatalytic ammonia synthesis.
Radically Enhanced Dual Recognition
Authors: Chen Xiao‐Yang , Mao Haochuan , Feng Yuanning , Cai Kang , Shen Dengke , Wu Huang , Zhang Long , Zhao Xingang , Chen Hongliang , Song Bo , Jiao Yang , Wu Yong , Stern Charlotte L. , Wasielewski Michael R. , Stoddart J. Fraser
Published: August 2021

Complexation between a viologen radical cation (V.+) and cyclobis(paraquat‐p‐phenylene) diradical dication (CBPQT2(.+)) has been investigated and utilized extensively in the construction of mechanically interlocked molecules (MIMs) and artificial molecular machines (AMMs). The selective recognition of a pair of V.+ using radical‐pairing interactions, however, remains a formidable challenge. Herein, we report the efficient encapsulation of two methyl viologen radical cations (MV.+) in a size‐matched bisradical dicationic host — namely, cyclobis(paraquat‐2,6‐naphthalene)2(.+), i.e., CBPQN2(.+). Central to this dual recognition process was the choice of 2,6‐bismethylenenaphthalene linkers for incorporation into the bisradical dicationic host. They provide the space between the two bipyridinium radical cations in CBPQN2(.+) suitable for binding two MV.+ with relatively short (3.05–3.25 Å) radical‐pairing distances. The size‐matched bisradical dicationic host was found to exhibit highly selective and cooperative association with the two MV.+ in MeCN at room temperature. The formation of the tetrakisradical tetracationic inclusion complex — namely, [(MV)2⊂CBPQN]4(.+) – in MeCN was confirmed by VT 1H NMR, as well as by EPR spectroscopy. The solid‐state superstructure of [(MV)2⊂CBPQN]4(.+) reveals an uneven distribution of the binding distances (3.05, 3.24, 3.05 Å) between the three different V.+, suggesting that localization of the radical‐pairing interactions has a strong influence on the packing of the two MV.+ inside the bisradical dicationic host. Our findings constitute a rare example of binding two radical guests with high affinity and cooperativity using host‐guest radical‐pairing interactions. Moreover, they open up possibilities of harnessing the tetrakisradical tetracationic inclusion complex as a new, orthogonal and redox‐switchable recognition motif for the construction of MIMs and AMMs.
Bead‐free and tough electrospun PCL/gelatin/PGS ternary nanofibrous scaffolds for tissue engineering application
Authors: Behtouei Ebrahim , Zandi Mojgan , Askari Fahimeh , Daemi Hamed , Zamanlui Soheila , Arabsorkhi‐Mishabi Amirhesam , Pezeshki‐Modaress Mohamad
Published: August 2021

Poly(glycerol sebacate) (PGS) is a biodegradable and biocompatible polyester that is increasingly used in the biomedical field. Herein, a novel ternary poly(ε‐caprolactone)/gelatin/PGS (PCL/gelatin/PGS) blend nanofibers were designed and fabricated with a wide range of chemical compositions, mechanical properties, and modulated degradability levels. PGS blends with gelatin are commonly used for enhancing electrospinability but their low‐mechanical properties, lack of structural stability in an aqueous medium, and unmodulated degradation behavior limited their application. Blending PGS and gelatin with PCL could improve their properties in a ternary structure. In addition, considering ternary blends of PCL/gelatin/PGS, an enhancement of hydrophilicity due to the presence of gelatin in the system is expected, resulting in better biocompatibility and controlled biodegradation. By increasing the polymer concentration, voltage, and distance of the needle to the collector, the bead‐free electrospun nanofibers were obtained. The ternary blend nanofibers with an equal weight ratio of polymers, T33 (containing 33 wt% PGS, 33 wt% gelatin, and 33 wt% PCL), possess more than a 4‐fold increase in tensile strength (7 MPa) and 89‐fold increase in elongation at break (1760.6%) compared to gelatin/PGS binary nanofibers. In vitro studies on glioma cells showed well attachment and proliferation of C6 glioma cells. The obtained results demonstrated the potential of these scaffolds for nerve tissue engineering applications.
Carboxylated nanocellulose superabsorbent: Biodegradation and soil water retention properties
Authors: Barajas‐Ledesma Ruth M. , Wong Vanessa N. L. , Little Karen , Patti Antonio F. , Garnier Gil
Published: August 2021

In this study, TEMPO (2,2,6,6‐tetramethylpiperidine‐1‐oxyl)‐oxidized nanocellulose superabsorbents are prepared using three different drying techniques: freeze‐dried, and oven‐dried at low and high temperatures. The benefits are investigated by evaluating the superabsorbent structure, composition and application rate. The absorption performance of nanocellulose superabsorbents is affected by the concentration and type of salts in the soil water extracts. Oven‐dried at 50°C SAP presents the highest ionic sensitivity attributed to its large number of accessible carboxylate groups. The water retention of the soil treatments increases with increasing application rate. Soil treated with the freeze‐dried superabsorbent shows the highest water retention, whereas those amended with the 50°C oven‐dried SAP remain moist the longest. The biodegradation rate of these materials depends on the application rate and nutrient availability. Carboxylated nanocellulose superabsorbents emerge as high‐performance biodegradable materials for agricultural use, able to replace the current non‐biodegradable petrochemical‐based superabsorbents.
Locust bean gum‐polyvinyl alcohol hydrogels: Synthesis, characterization, swelling behaviors, and mathematical models
Authors: Matar Ghassan H. , Andac Muberra , Elmas Aykut
Published: August 2021

In this study, locust bean gum/polyvinyl alcohol (LBG/PVA) hydrogels were synthesized by the gel casting method without using toxic crosslinking agents. Infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and thermogravimetric analysis (TGA) methods were used for characterization of the synthesized hydrogels. Scanning electron microscopy (SEM) was used for observation surface morphology of the hydrogel and swelled hydrogels. The Swelling behavior of prepared hydrogels was investigated and the data were interpreted by various kinetic models. The prepared hydrogels showed pH and temperature‐responsive behavior. The maximum swelling ratio was evaluated as 607.72 at 37°C. The diffusional exponent values (n) were found as 0.5946, 0.5028, and 0.2785 at 4, 25, and 37°C, respectively. According to the n values, it was found that non‐Fickian diffusion dominates the swelling process. The obtained diffusion prediction curves were fitted to three different models: Higuchi, Peppas, and Elmas models. Among the results, Elmas model has better fits at 277 K and 298 K while Peppas model is better at 310 K. The results indicated that LBG/PVA hydrogels could be a candidate biomaterial for drug delivery applications.
Recent advances of environmental pollutants detection via paper‐based sensing strategy
Authors: Zou Xue , Ji Yayun , Li Hangzhou , Wang Zhaoli , Shi Linhong , Zhang Shengli , Wang Tengfei , Gong Zhengjun
Published: August 2021

Paper has become one of the most promising substrates for building low‐cost and powerful sensing platforms due to its self‐pumping ability and compatibility with multiple patterning methods. Paper‐based sensors have been greatly developed in the field of environmental monitoring. In this review, we introduced the research and application of paper‐based sensors in environmental monitoring, focusing on the deposition and patterning methods of building paper‐based sensors, and summarized the applications of detecting environmental pollutants, including metal ions, anions, explosives, neurotoxins, volatile organic compounds, and small molecules. In addition, the development prospects and challenges of promoting paper‐based sensors are also discussed. The current review will provide references for the construction of portable paper‐based sensors, and has implications for the field of on‐site real‐time detection of the environment.
Increased modularity of the resting‐state network in children with nonsyndromic cleft lip and palate after speech rehabilitation
Authors: Cheng Hua , Rao Bo , Zhang Wenjing , Chen Renji , Peng Yun
Published: August 2021

Introduction

Speech therapy is the primary management followed the physical management through surgery for children with nonsyndromic cleft lip and palate (NSCLP). However, the topological pattern of the resting‐state network after rehabilitation remains poorly understood. We aimed to explore the functional topological pattern of children with NSCLP after speech rehabilitation compared with healthy controls.

Methods

We examined 28 children with NSCLP after speech rehabilitation (age = 10.0 ± 2.3 years) and 28 healthy controls for resting‐state functional MRI. We calculated functional connections and the degree strength, betweenness centrality, network clustering coefficient (Cp), characteristic path length (Lp), global network efficiency (Eg), local network efficiency (Eloc), modularity index (Q), module number, and participation coefficient for the between‐group differences using two‐sample t tests (corrected p < .05). Additionally, we performed a correlation analysis between the Chinese language clear degree scale (CLCDS) scores and topological properties in children with NSCLP.

Results

We detected significant between‐group differences in the areas under the curve (AUCs) of degree strength and betweenness centrality in language‐related brain regions. There were no significant between‐group differences in module number, participation coefficient, Cp, Lp, Eg, or Eloc. However, the Q (density: 0.05–0.30) and QAUC (t = 2.46, p = .02) showed significant between‐group differences. Additionally, there was no significant correlation between topological properties of statistical between‐group differences and CLCDS scores.

Conclusions

Although nodal metric differences existed in the language‐related brain regions, the children with NSCLP after speech rehabilitation had similar global network properties, module numbers, and participation coefficient, but increased modularity. Our results suggested that children with NSCLP achieved speech rehabilitation through function specialization in the language‐related brain regions. The resting‐state topology pattern could be of substantive neurobiological importance and potential imaging biomarkers for speech rehabilitation.
Vasopressors independently associated with mortality in acute myocardial infarction and cardiogenic shock
Authors: Basir Mir B. , Lemor Alejandro , Gorgis Sarah , Taylor Angela M. , Tehrani Behnam , Truesdell Alexander G. , Bharadwaj Aditya , Kolski Brian , Patel Kirit , Gelormini Joseph , Todd Josh , Lasorda David , Smith Craig , Riley Robert , Marso Steve , Federici Robert , Kapur Navin K. , O'Neill William W. ,   The National Cardiogenic Shock Initiative Investigators
Published: August 2021

Background

Increasing vasopressor dose is associated with increasing mortality in patients presenting with acute myocardial infarction and cardiogenic shock (AMICS). It is unknown whether the use of vasopressors is independently harmful or if their use is secondary to decreasing intrinsic cardiac power output (CPO). Mechanical circulatory support (MCS) devices enhance CPO. We sought to evaluate the independent impact of increasing vasopressor dose on survival in the National Cardiogenic Shock Initiative (NCSI).

Methods

The NCSI is a single arm prospective trial evaluating outcomes associated with the use of MCS using Impella in patients with AMICS. Early initiation of MCS placement before percutaneous coronary intervention (PCI) and rapid de‐escalation of vasopressors guided by systematic use of invasive hemodynamic measures led to 70% in‐hospital survival for the first 300 patients enrolled from July 2016 to December 2019 in 57 U.S. sites.

Results

Hemodynamic measures were obtained immediately after MCS and PCI. Survival curves were constructed based on CPO and use of vasopressors. For patients with CPO ≤0.6 W, survival was 77.3%, 45.0%, and 35.3% when 0, 1, or ≥ 2 vasopressors were used (p = 0.02). Similarly, for patients with CPO >0.6 W survival was 81.7%, 72.6%, and 56.8%, respectively (p = 0.01). Logistic regression analysis demonstrated that increasing vasopressor requirements were independently associated with increasing mortality (p = 0.02).

Conclusion

Increasing vasopressor requirement is associated with increased mortality in AMICS independent of underlying CPO. Methods to decrease the need for vasopressors may enhance survival in AMICS.
Design of Oxygen‐doped Co3S4 Hollow Nanosheets by Suppressed Sulfurization for Supercapacitors
Authors: Zhang Xu , Tian Yuhan , Lu Wang , Yang Shixuan , Qu Ning , Zhang Qiang , Lei Da , Liu Anmin
Published: August 2021

Cobalt sulfides can be considered as auspicious electrode materials for supercapacitors due to the good electrical conductivity and high reversible redox capability. In this study, the O‐doped Co3S4 hollow nanosheets supported on carbon paper (O−Co3S4/CP) are facilely prepared through a suppressed sulfurization method by using CP‐supported Co‐ZIF as the precursor and methanol as the solvent. The hollow nanosheets not only offer fast transport pathways but also provide abundant redox active sites. Furthermore, theoretical calculations indicate that the O doping can enhance the adsorption ability of OH− on O−Co3S4 with electrochemical activity and electrical conductivity improvement. Owing to the advantages of the appropriate composition and unique structure, the as‐made hollow structure O−Co3S4/CP shows a remarkable specific capacitance of 755 F g−1 at a current density of 1 A g−1, while a good rate performance of 65 % capacitance retention at 10 A g−1 can be reached. Moreover, the asymmetric supercapacitors assembled by O−Co3S4/CP and activated carbon electrodes yield an energy density of 21.3 Wh kg−1 with power density of 0.75 kW kg−1. The present work can offer a useful guidance for the exploitation of O doped cobalt sulfides hollow nanosheets for supercapacitors.
Iron Binding in the Ferroxidase Site of Human Mitochondrial Ferritin
Authors: Ciambellotti Silvia , Pratesi Alessandro , Tassone Giusy , Turano Paola , Mangani Stefano , Pozzi Cecilia
Published: August 2021

Ferritins are nanocage proteins that store iron ions in their central cavity as hydrated ferric oxide biominerals. In mammals, further the L (light) and H (heavy) chains constituting cytoplasmic maxi‐ferritins, an additional type of ferritin has been identified, the mitochondrial ferritin (MTF). Human MTF (hMTF) is a functional homopolymeric H‐like ferritin performing the ferroxidase activity in its ferroxidase site (FS), in which Fe(II) is oxidized to Fe(III) in the presence of dioxygen. To better investigate its ferroxidase properties, here we performed time‐lapse X‐ray crystallography analysis of hMTF, providing structural evidence of how iron ions interact with hMTF and of their binding to the FS. Transient iron binding sites, populating the pathway along the cage from the iron entry channel to the catalytic center, were also identified. Furthermore, our kinetic data at variable iron loads indicate that the catalytic iron oxidation reaction occurs via a diferric peroxo intermediate followed by the formation of ferric‐oxo species, with significant differences with respect to human H‐type ferritin.
Reactivity and Passivation of Fe Nanoclusters on h‐BN/Rh(111)
Authors: Waleska Natalie J. , Düll Fabian , Bachmann Philipp , Hemauer Felix , Steinhauer Johann , Papp Christian
Published: August 2021

The reactivity of iron nanocluster arrays on h‐BN/Rh(111) was studied using in situ high‐resolution X‐ray photoelectron spectroscopy. The morphology and reactivity of the iron nanoclusters (Fe‐NCs) were investigated by CO adsorption. On‐top and hollow/edge sites were determined to be the available adsorption sites on the as‐prepared Fe‐NCs and CO dissociation was observed at 300 K. C‐ and O‐precovered Fe‐NCs showed no catalytic activity towards CO dissociation because the hollow/edge sites were blocked by the C and O atoms. Therefore, these adsorption sites were identified to be the most active sites of the Fe‐NCs.
Imaging and Identifying BSA Biofouling through the Combination of Fluorescence Microscopy and Flux Experiments
Authors: Widing Charles S. , Ruffle‐Deignan Nathan R. , Stennett Elana M. S.
Published: August 2021

Biofouling decreases efficiency of membrane‐based water filtration, like desalination, because fouling decreases flow rates. Understanding biofouling mechanism is crucial for increased implementation of desalination though few techniques for studying this exist. Flux experiments are combined with fluorescent membrane images to determine the biofouling mechanism of bovine serum albumin (BSA), a common model protein, with two mixed cellulose ester membranes. Samples containing 1% to 12% fluorescently tagged BSA (remaining protein unlabeled) are tested to determine the ideal amount of labeled protein. Due to large standard deviation in the fouling decays, the relative flux decays are fit for statistical analysis. No correlation between the decay and amount of labeled protein is found, suggesting the dye has little impact on the fouling. A 2.5% or 5% labeled protein sample is optimal to generate images and visualize the beginning of cake formation (blockage of membrane pores). By fitting the flux data to biofouling mechanism equations, it is concluded BSA deposits in the membrane pores eventually leading to cake formation. These results are corroborated using scanning electron microscopy images. Combining flux and fluorescence microscopy allows for further insight into biofouling mechanism and can be applied to other biological molecules to improve filtration techniques.
Tools for Planning Local Mitigation of Water‐Driven Soil Erosion Resulting from Impacts of Future Climate Change
Authors: Köhn Janine , Meißner Ralph , Rupp Holger , Reinstorf Frido
Published: August 2021

Due to the consequences of climate change impacts municipal planners and local administrations need to develop long‐term strategies to protect soil bodies. For this purpose, practicable and free available tools are developed, that allow to estimate the erosivity of rainfall and discharge, considering the effects of land use changes and climate change impacts. This paper presents a stepwise estimation of water erosivity at agricultural areas as well as streams using the developed practicable tools step model of infiltration with calculation of direct flow and soil erosion (ero‐SMINF), German universal soil loss equation integrated into a geographic information system (ABAGis), and stream erosion model (SEM). The tools are developed and tested at two catchments in mountainous areas in Central Germany, Vietzbach and Regenbeek. The results for the Vietzbach catchment, which is mostly affected by sheet erosion, indicated that most of the erosive events occur during summer. The most probable change in soil erosion resulting from climate change (RCP8.5) shows an increasing erosion of up to 16% comparing to the current state. In the Regenbeek catchment, where stream bed erosion is dominant, calculations with the SEM show for the same scenario, that erosion can be reduced mainly by widening the stream bed.
A biometrics‐based anonymous authentication and key agreement scheme for wireless sensor networks
Authors: Fan Qing , Chen Jianhua , Xu Feng , Li Li , Luo Min
Published: August 2021

Wireless sensor networks (WSNs) are widespreadly applicable for information acquisition and processing in various fields such as military, healthcare, envrionment monitoring, and so on. WSNs have three main components: sensors, gateways, and users. The sensing information from sensors is transmitted to users through gateways. However, the public wireless networks are vulnerable to malicious active and passive attacks, which could bring security and privacy issues. Numerous two‐factor based authentication and key agreement (AKA) protocols have been proposed to solve these issues, whereas these schemes still have some deficiencies. Three‐factor based authentication method can make up for the drawbacks of two‐factor based schemes. Kumari and Renuka put forward a biometrics‐based AKA for WSNs with elliptic curve cryptography (ECC). But their scheme cannot maintain anonymity and resist to impersonality attack, replay attack, and DoS attack. In this article, we propose a biometrics‐based anonymous AKA scheme, which is equipped with the covered security requirements of WSNs. Meanwhile, the proposed scheme are provably secure in the three‐party AKA security model. Performance analysis demonstrates that our scheme has better security properties, communication cost, and computational cost compared with five recent and related schemes.
Performance evaluation of Java/PCJ implementation of parallel algorithms on the cloud (extended version)
Authors: Nowicki Marek , Górski Łukasz , Bała Piotr
Published: August 2021

Large‐scale computing and data processing with cloud resources is gaining popularity. However, the usage of the cloud differs from traditional high‐performance computing (HPC) systems and both algorithms and codes have to be adjusted. This work is often time‐consuming and performance is not guaranteed. To address this problem we have developed the PCJ library (parallel computing in Java), a novel tool for scalable HPC and big data processing in Java. In this article, we present a performance evaluation of parallel applications implemented in Java using the PCJ library. The performance evaluation is based on the examples of highly scalable applications of different characteristics focusing on CPU, communication or I/O. They run on the traditional HPC system and Amazon web services Cloud as well as Linaro Developer Cloud. For the clouds, we have used Intel x86 and ARM processors for running Java codes without changing any line of the program code and without the need for time‐consuming recompilation. Presented applications have been parallelized using the partitioned global address space programming model and its realization in the PCJ library. Our results prove that the PCJ library, due to its performance and ability to create simple portable code, has great promise to be successful for the parallelization of various applications and run them on the cloud with a performance close to HPC systems.
Variation of forage quality traits in Tunisian populations of Brachypodium hybridum in response to phosphorus deficiency
Authors: Neji Mohamed , Tlahig Samir , Hessini Kamel , Taamalli Wael , Abdelly Chedly , Kouas Saber
Published: August 2021

Natural populations of plants may express plastic response, evolve local adaptation, or combine both mechanisms to enhance their genetic variation. Here, 79 lines from Tunisian Brachypodium hybridum populations were cultivated in two contrasting phosphorus (P) availability levels, and their genetic variation was investigated using forage quality traits to identify the mechanisms governing their genetic variation. Results revealed large variation among populations for most traits and separation between coastal and inland populations in both P levels. All traits revealed high heritability, and the response of most traits to P deficiency was influenced by the population effect which accounted 52.38% of the variation, indicating strong population differentiation. Although significant for most traits, only 18.13% of variation was attributed to P treatment, suggesting little plastic response to P deficiency. However, the lack of population × treatment effect for most traits suggested a common plastic response in populations. Moreover, 56.99% of variation was attributed to environmental factors with distance to coastline, precipitation seasonality, and annual precipitation being the major factors, suggesting that the strong population differentiation reflects local adaptation to specific environments. Contrary to coastal populations characterized by high levels of fiber‐related traits, the inland ones displayed high values of most energy‐related traits, suggesting that these latter were characterized by higher forage quality. Overall, our results suggested that the effect of local adaptation overrides the effect of phenotypic plasticity regarding the variation of forage quality traits, indicating a broad adaptive genetic differentiation among the populations of B. hybridum in response to P deficiency.
Native and oxidised lipoproteins negatively regulate the serum amyloid A‐induced NLRP3 inflammasome activation in human macrophages
Authors: Nurmi Katariina , Niemi Katri , Kareinen Ilona , Silventoinen Kristiina , Lorey Martina B , Chen Yan , Kouri Vesa‐Petteri , Parantainen Jukka , Juutilainen Timo , Öörni Katariina , Kovanen Petri T , Nordström Dan , Matikainen Sampsa , Eklund Kari K
Published: August 2021

Objectives

The NLRP3 inflammasome plays a key role in arterial wall inflammation. In this study, we elucidated the role of serum lipoproteins in the regulation of NLRP3 inflammasome activation by serum amyloid A (SAA) and other inflammasome activators.

Methods

The effect of lipoproteins on the NLRP3 inflammasome activation was studied in primary human macrophages and THP‐1 macrophages. The effect of oxidised low‐density lipoprotein (LDL) was examined in an in vivo mouse model of SAA‐induced peritoneal inflammation.

Results

Native and oxidised high‐density lipoproteins (HDL3) and LDLs inhibited the interaction of SAA with TLR4. HDL3 and LDL inhibited the secretion of interleukin (IL)‐1β and tumor necrosis factor by reducing their transcription. Oxidised forms of these lipoproteins reduced the secretion of mature IL‐1β also by inhibiting the activation of NLRP3 inflammasome induced by SAA, ATP, nigericin and monosodium urate crystals. Specifically, oxidised LDL was found to inhibit the inflammasome complex formation. No cellular uptake of lipoproteins was required, nor intact lipoprotein particles for the inhibitory effect, as the lipid fraction of oxidised LDL was sufficient. The inhibition of NLRP3 inflammasome activation by oxidised LDL was partially dependent on autophagy. Finally, oxidised LDL inhibited the SAA‐induced peritoneal inflammation and IL‐1β secretion in vivo.

Conclusions

These findings reveal that both HDL3 and LDL inhibit the proinflammatory activity of SAA and this inhibition is further enhanced by lipoprotein oxidation. Thus, lipoproteins possess major anti‐inflammatory functions that hinder the NLRP3 inflammasome‐activating signals, particularly those exerted by SAA, which has important implications in the pathogenesis of cardiovascular diseases.
The description of non‐linear interactions of wave and non‐wave modes in a non‐adiabatic plasma flow
Authors: Perelomova Anna
Published: August 2021

The method of derivation of non‐linear equations for interacting modes is explained and applied to a plasma's flow affected by a magnetic field. It is based on the linear projecting of the total perturbation field into specific variations of variables in individual modes of a flow. The method may be applied in many examples of fluid flows with different mechanisms of non‐adiabaticity. It is of special importance in complex flows with large number of different modes. A flow of an ionized gas is one of the examples of such flows: it incorporates fast, slow magnetosonic modes, the Alfvén mode and the entropy mode. In the frames of this study, the wave vector may form an arbitrary angle with the straight equilibrium magnetic field. Thermal conduction, dynamic viscosity and a generic heating–cooling function, which is responsible for an energy inflow and radiative losses, are taken into account. Variable and plasma‐β, diversity of the wave modes and a balance of different mechanisms of non‐adiabaticity make the description of non‐linear interaction of modes special. The non‐linear excitation of the magnetosonic mode by the entropy mode is considered as an example.
Low attainment in mathematics: An analysis of 60 years of policy discourse in England
Authors: Hodgen Jeremy , Foster Colin , Brown Margaret
Published: August 2021

The problem of low attainment in mathematics has been an increasingly prominent feature of the policy discourse in England over the last 60 years; however, evidence from comparative studies indicates that little progress has been made in finding a solution. In this paper, we analyse the changing policy discourse of low attainment in mathematics through the main reports and speeches published in England, beginning with the Newsom Report, Half Our Future, in 1963, and continuing to the present day. We chart the evolving perspectives on the nature of ability, expectations, curriculum ideology and frame of reference through the changing language used in these documents, noting tensions and inconsistencies which arise through continuing lack of clarity about definitions and assumptions.
A detailed tutorial survey on VANETs: Emerging architectures, applications, security issues, and solutions
Authors: Sharma Sparsh , Kaul Ajay , Ahmed Suhaib , Sharma Surbhi
Published: August 2021

Vehicular ad‐hoc network (VANET) is an emerging field of mobile ad‐hoc network (MANET) which facilitates intelligent transport system (ITS). It thus helps in enhancing the real‐time driving experience and road safety. Due to association of VANET with life‐critical applications, there is a dire need to understand each and every aspect of it in terms of architecture, security, applications, routing, and so forth, before bringing it into implementation. Although there exist numerous studies on VANETs, they tend to cover only individual aspects of it. This first of its kind survey aims to provide a combined and thorough study of each aspect of VANET along with their advantages and limitations in a single solid document. Different architectures proposed till date have been explored along with their shortcomings and the possible applications which are supported in VANETs. Comparison of various wireless technologies used in VANET based on the range requirement of different VANET applications and various routing protocols that are best suited for VANET on the basis of the application requirement is done. It also discusses the various security attacks possible in VANET, the risks associated with them, and the possible security solutions available for these attacks. Various optimization and bio‐inspired techniques as well as intrusion detection systems for enhancing security in VANET are also analyzed. Finally, various simulators have been investigated, and comprehensive analysis has been done with respect to the feasibility of implementation of VANETs in these simulators. This research is believed to assist the researchers in understanding the current state of research in VANETs.
Fault‐tolerant wireless‐optical broadband access network with cluster‐controlled architecture
Authors: Prabha B. , Ramprasad A. V.
Published: August 2021

The ever increasing demand in wireless connectivity has led PON networks suffer from limitations in mobility and wide area coverage. Wireless networks suffer by bandwidth limitations. Hybridization uses the best characteristics of all networks: wireless networks and optical networks. A lightweight wireless mesh network is a wireless‐optical broadband access network (WOBAN), which has a front end and background effective bandwidth optical network. WOBAN has already suffered from two large network feature faults as well as feeder and fiber breaks. Cluster‐based protection (CBP) mechanism is proposed in order to increase traffic recovery reliability and reduce backup fiber deployment. With minimal fiber distribution cost, CBP efficiently manages single and simultaneous failures from many segments. Long‐term evolution (LTE) technique‐based CBP is implemented in WOBAN. Faults are analyzed by injecting wireless/distribution fiber/multiple feeder fiber. The novel fault tolerant network is built using an efficient automated failure detection and rerouting (AFDRR) algorithm. An efficient automated failure detection and rerouting (AFDRR) algorithm is used for developing the novel fault‐tolerant network. Implementation of orthogonal frequency division multiplexing (OFDM) technology‐based AFDRR‐CBP on WOBAN‐LTE network with the same scenario is analyzed through simulation. The performance measures are compared among CBP‐WOBAN‐LTE network, AFDRR‐CBP‐WOBAN‐LTE network, and OFDM‐based AFDRR‐CBP‐WOBAN‐LTE networks. From the result obtained, it will be revealed that the suggested methodology throughput ratio will increase up to 24.4% when compared to other methodology.
Effective distance of volatile cues for plant–plant communication in beech
Authors: Hagiwara Tomika , Ishihara Masae Iwamoto , Takabayashi Junji , Hiura Tsutom , Shiojiri Kaori
Published: August 2021

In response to volatiles emitted from a plant infested by herbivorous arthropods, neighboring undamaged conspecific plants become better defended against herbivores; this is referred to as plant‒plant communication. Although plant‒plant communication occurs in a wide range of plant species, most studies have focused on herbaceous plants. Here, we investigated plant‒plant communication in beech trees in two experimental plantations in 2018 and one plantation in 2019. Approximately 20% of the leaves of a beech tree were clipped in half in the spring seasons of 2018 and 2019 (clipped tree). The damage levels to leaves in the surrounding undamaged beech trees were evaluated 90 days after the clipping (assay trees). In both years, the damage levels decreased with a reduction in the distance from the clipped tree. In 2019, we also recorded the damage levels of trees that were not exposed to volatiles (nonexposed trees) as control trees and found that those that were located <5 m away from clipped trees had significantly less leaf damage than nonexposed trees. By using a gas chromatograph–mass spectrometer, ten and eight volatile compounds were detected in the headspaces of clipped and unclipped leaves, respectively. Among them, the amount of (Z)‐3‐hexenyl acetate in clipped leaves was significantly higher than that in nonclipped leaves. Our result suggests that green leaf volatiles such as (Z)‐3‐hexenol and (Z)‐3‐hexenyl acetate and other volatile organic compounds emitted from clipped trees induced defenses in the neighboring trees within the 5 m radius. The effective distances of plant‒plant communication in trees were discussed from the viewpoint of the arthropod community structure in forest ecosystems.
Magnetic Behaviors and Nonlinear Optical Properties of Heteroleptic Bis(phthalocyaninato) Holmium Compounds
Authors: Yang Wei , Ma Li , Liu Chao , Sun Tingting , Jiang Jianzhuang
Published: August 2021

Incorporating unsubstituted phthalocyanine and dibutylamino‐substituted phthalocyanine into sandwich‐type rare earth compounds has provided a heteroleptic bis(phthalocyaninato) trivalent holmium analogue. The rich redox states of sandwich‐type tetrapyrole‐based metal compounds lead to the formation of [(Pc)Ho{Pc{N(C4H9)2}8}]. (1) and [(Pc)Ho{Pc[N(C4H9)2]8}]− ⋅ [(C4H9)4N]+ (2) as a neutral unprotonated and reduced state, respectively. The detailed sandwich‐type structures of these two homologs with different redox states are disclosed using single crystal X‐ray diffraction analyses. In addition, the differences in these two compounds with/without one radical have been ascertained by fundamental spectroscopic instruments, enabling the adjustment of the corresponding static magnetic behaviors and nonlinear optical properties owing to the presence/absence of radical‐Ho(III) interaction and different electron cloud density delocalized around 1 and 2.
A Novel Electrochemical Glassy Carbon Electrode Modified with Carbon Black and Glyceline Deep Eutectic Solvent within a Crosslinked Chitosan Film for Simultaneous Determination of Acetaminophen and Diclofenac
Authors: Piton Gabriela R. , Augusto Karen K. L. , Wong Ademar , Moraes Fernando C. , Fatibello‐Filho Orlando
Published: August 2021

Glyceline, reline, or ethaline deep eutectic solvents and carbon black nanoparticles within a crosslinked chitosan film are investigated as glassy carbon electrode modifiers for the first time. The selected 5 mg mL−1 glyceline modified GCE was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy. Simultaneous determination of acetaminophen and diclofenac by differential pulse adsorptive stripping voltammetry (DPAdSV) presented limits of detection of 2.6×10−8 and 5.2×10−8 mol L−1 for acetaminophen and diclofenac, respectively, in pharmaceutical and biological samples. The obtained results were compared with those obtained by HPLC at a confidence level of 95 %.
Modelling sediment (dis)connectivity across a river network to understand locational‐transmission‐filter sensitivity for identifying hotspots of potential geomorphic adjustment
Authors: Khan Sana , Fryirs Kirstie , Bizzi Simone
Published: August 2021

Rivers act as ‘jerky conveyor belts’ that transmit fluxes of flow and sediment downstream. This transmission of fluxes can be highly variable within a drainage basin resulting in either abrupt or gradational sediment (dis)connectivity patterns and processes. This study assesses sediment (dis)connectivity across a basin as a means to understand the locational, transmission and filter sensitivity properties of a fluvial system. Drawing upon the case study of Richmond River Catchment, New South Wales, Australia we use the concepts of effective catchment area and buffers, along with graph theory and an empirical sediment transport model CASCADE (Catchment Sediment Connectivity and Delivery), to assess (1) the degree to which modelled sediment cascades along the river network are connected or disconnected (2) how the position, pattern and configuration of (dis)connection facilitates or restricts geomorphic adjustment in different parts of a catchment, and (3) use the findings as a basis to explain the locational‐transmission‐filter sensitivity of the catchment. We use this analysis to segregate supply limited and transport limited reaches and identify various controls on sediment dynamics: in‐stream sediment storage units, junctions between different geomorphic river types, tributary confluences and sediment storage units within partly confined floodplain units. Such analysis lays the foundation for network scale identification of potential hotspots of geomorphic adjustment.
Do we need to reclassify the social systems of gregarious apes?
Authors: Grueter Cyril C. , Wilson Michael L.
Published: August 2021

Decades of research have led to a solid understanding of the social systems of gregarious apes: chimpanzees, bonobos, gorillas, and gibbons. As field studies have increasingly collected data from multiple neighboring habituated groups, genetic and social interconnections have been revealed. These findings provide a more nuanced picture of intergroup relations in apes, and have led to claims in the literature that some ape taxa have multilevel societies. A multilevel society is defined as a nested collection of social entities comprising at least two discernible levels of social integration between the individual and the population. We argue that the evidence for multilevel sociality sensu stricto in apes is currently inconclusive and that it is premature to abandon the traditional classification of ape social systems. However, available findings appear to be consistent with the existence of some degree of higher social grouping patterns. We propose the termsupra‐group organizationwhich may adequately capture ape social systems when viewed from a top‐down perspective.
Remote research methods for Human–AI–Robot Teaming
Authors: Lematta Glenn J. , Corral Christopher C. , Buchanan Verica , Johnson Craig J. , Mudigonda Anagha , Scholcover Federico , Wong Margaret E. , Ezenyilimba Akuadasuo , Baeriswyl Manuel , Kim Jimin , Holder Eric , Chiou Erin K. , Cooke Nancy J.
Published: August 2021

This study focuses on methodological adaptations and considerations for remote research on Human–AI–Robot Teaming (HART) amidst the COVID‐19 pandemic. Themes and effective remote research methods were explored. Central issues in remote research were identified, such as challenges in attending to participants' experiences, coordinating experimenter teams remotely, and protecting privacy and confidentiality. Instances of experimental design overcoming these challenges were identified in methods for recruitment and onboarding, training, team task scenarios, and measurement. Three case studies are presented in which interactive in‐person testbeds for HART were rapidly redesigned to function remotely. Although COVID‐19 may have temporarily constrained experimental design, future HART studies may adopt remote research methods to expand the research toolkit.
The sensitivity of runoff generation to spatial snowpack uniformity in an alpine watershed: Green Lakes Valley, Niwot Ridge Long‐Term Ecological Research station
Authors: Badger Andrew M. , Bjarke Nels , Molotch Noah P. , Livneh Ben
Published: August 2021

Seasonal water storage in high‐elevation alpine catchments are critical sources of water for mountainous regions like the western U.S. The spatial distribution of snow in these topographically complex catchments is primarily governed by orography, solar radiation, and wind redistribution. While the effect of solar shading is relatively consistent from year‐to‐year, the redistribution of snow due to wind is more variable – capable of producing snowpacks that have varying degrees of uniformity across these hydrologically‐important catchments. A reasonable hypothesis is that a warmer climate will cause snowfall to become more dense (i.e. wetter and heavier), possibly leading to less wind redistribution and thus produce a more uniformly distributed snowpack across the landscape. In this study, we investigate the role of increasingly uniform spatial snowpack distributions on streamflow generation in the Green Lakes Valley Niwot Ridge Long Term Ecological Research station, within the headwaters of the Boulder Creek watershed in Colorado. A set of idealized hydrologic simulation experiments driven by reconstructed snowpacks spanning 2001–2014 show that more a more uniform spatial snowpack distribution leads to an earlier melt‐out of 31 days on average and tends to produce less total streamflow, with maximum decreases as large as 7.5%. Isolating the role of snowpack heterogeneity from melt‐season precipitation, we find that snowpack uniformity reduces total streamflow by as much as 13.2%. Reductions in streamflow are largely explained by greater exposure to solar radiation in the uniformly distributed case relative to a more heterogeneous snowpack, with this exposure driving shifts towards earlier snowmelt and changes in soil water storage. Overall, we find that the runoff efficiency from shallower snowpacks is more sensitive to the effects of uniformity than deeper snowpacks, which has potential implications for a warming climate where shallower snowpacks and enhanced sensitivities may be present.
Is the soil moisture precipitation feedback enhanced by heterogeneity and dry soils? A comparative study
Authors: Graf Maximilian , Arnault Joël , Fersch Benjamin , Kunstmann Harald
Published: August 2021

The interaction between the land surface and the atmosphere is a crucial driver of atmospheric processes. Soil moisture and precipitation are key components in this feedback. Both variables are intertwined in a cycle, that is, the soil moisture – precipitation feedback for which involved processes and interactions are still discussed. In this study the soil moisture – precipitation feedback is compared for the sempiternal humid Ammer catchment in Southern Germany and for the semiarid to subhumid Sissili catchment in West Africa during the warm season, using precipitation datasets from the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), from the German Weather Service (REGNIE) and simulation datasets from the Weather Research and Forecasting (WRF) model and the hydrologically enhanced WRF‐Hydro model. WRF and WRF‐Hydro differ by their representation of terrestrial water flow. With this setup we want to investigate the strength, sign and variables involved in the soil moisture – precipitation feedback for these two regions. The normalized model spread between the two simulation results shows linkages between precipitation variability and diagnostic variables surface fluxes, moisture flux convergence above the surface and convective available potential energy in both study regions. The soil moisture – precipitation feedback is evaluated with a classification of soil moisture spatial heterogeneity based on the strength of the soil moisture gradients. This allows us to assess the impact of soil moisture anomalies on surface fluxes, moisture flux convergence, convective available potential energy and precipitation. In both regions the amount of precipitation generally increases with soil moisture spatial heterogeneity. For the Ammer region the soil moisture – precipitation feedback has a weak negative sign with more rain near drier patches while it has a positive signal for the Sissili region with more rain over wetter patches. At least for the observed moderate soil moisture values and the spatial scale of the Ammer region, the spatial variability of soil moisture is more important for surface‐atmosphere interactions than the actual soil moisture content. Overall, we found that soil moisture heterogeneity can greatly affect the soil moisture – precipitation feedback.
With Liberty and Black Linguistic Justice for All: Pledging Allegiance to Anti‐Racist Language Pedagogy
Authors: McMurtry Teaira
Published: August 2021

This article makes a case for why Black Language (BL) must be a part of teachers’ conceptualizations of multilingualism in U.S. contexts. BL is a living linguistic legacy, an embodiment of Black culture, and much more than simply a list of distinct grammatical features. For teachers to move toward dispositions and language and literacy pedagogical practices that are inclusive, just, and anti‐racist, they must become aware of and interrogate their real trouble with BL through guided and continuous critical, introspective, and reflexivity. After providing a brief linguistic understanding of BL, the author describes what happens when Black adolescents and adults discover that their language has a name, a rich history, and global influence‐‐it marks the onset of their Black Linguistic Consciousness‐raising (Baker‐Bell, 2020). The article ends with recommendations and resources for how teachers can start and continue to stand for anti‐racist linguistic justice in the classroom contexts and beyond.