bluuebunny/crossref_metadata_2025 huggingface dataset:
Tosyl/pyrrolyl-capped 1,3-enynes via t-BuOK-assisted reaction of TosMIC with acylethynylpyrroles: a new feature of this popular reagent
Authors: Gotsko Maxim D. , Saliy Ivan V. , Sobenina Lyubov’ N. , Ushakov Igor A. , Trofimov Boris A.
Published: August 2022

1-Tosyl-4-pyrrolyl-1,3-enynes have been synthesized in 37–68% yields by t-BuOK-assisted chemo selective reaction (reflux in THF, 1 h) of 2-(acylethynyl)pyrroles with tosylmethylisocyanide (TosMIC), a widespread reagent, which here manifests a new functionality.
Carboxylation of terminal alkynes with CO2 catalyzed by imidazolium-bridged bis(phenolato) rare-earth metal complexes
Authors: Shi Kai , Lu Chengrong , Zhao Bei
Published: August 2022

An imidazolium-bridged bis(phenolato) yttrium complex shows excellent catalytic reactivity in the direct carboxylation of terminal alkynes and further one-pot three-component esterification.
Mode-tunable, micro/nanoscale electrohydrodynamic deposition techniques for optoelectronic device fabrication
Authors: Duan Yongqing , Li Huayang , Yang Weili , Shao Zhilong , Wang Qilu , Huang YongAn , Yin Zhouping
Published: August 2022

Electrohydrodynamic deposition is capable of creating thin films by electrospray, micro/nanofibers by electrospinning and micro/nanodroplets by EHD jet printing. This jetting mode tunability presents advantages in optoelectronic devices fabrication.
Boosting the activity and stabilityviasynergistic catalysis of Co nanoparticles and MoC to construct a bifunctional electrocatalyst for high-performance and long-life rechargeable zinc–air batteries
Authors: Deng Xiaohua , Gu Xianrui , Deng Yingjie , Jiang Zhu , Chen Wenxuan , Dang Dai , Lin Wei , Chi Bin
Published: August 2022

We report a ZIF-67-derived multiphase doped carbon ORR/OER catalyst (Co/MoC-NC) with the synergistic catalysis of Co and MoC. ZABs assembled with Co/MoC-NC demonstrate an excellent power density (215.36 mW cm−2) and great durability (more than 300 h).
Copper(ii)-catalyzed oxidative ipso-annulation of N-arylpropiolamides and biaryl ynones with 1,3-diketones: construction of diketoalkyl spiro-trienones
Authors: Raji Reddy Chada , Kolgave Dattahari H. , Ajaykumar Uprety , Ramesh Remya
Published: August 2022

A diverse range of diketoalkylated spiro-trienones involving a copper(ii)-catalyzed cascade radical addition/ipso-annulation/dearomatization reaction of N-arylpropiolamides and biaryl ynones are synthesized.
Tuning the selectivity of amino acid recognition with dynamic covalent bond constrained fluorophores in aqueous media
Authors: She Zijian , Zou Hanxun , You Lei
Published: August 2022

Dynamic covalent bond constrained fluorophores were demonstrated for regulating the selectivity of amino acid recognition in aqueous media.
Effect of water-soluble fullerenes on macrophage surface ultrastructure revealed by scanning ion conductance microscopy
Authors: Ruan Hefei , Zhang Xuejie , Yuan Jinghe , Fang Xiaohong
Published: August 2022

Nanoscale morphological changes of macrophages characterized by contact-free SICM and their relationship with phagocytosis after C60-fullerene treatment demonstrate they are a potential phagocytosis inhibitor.
A ratiometric fluorescent sensor for detection of metformin based on terbium–1,10-phenanthroline–nitrogen-doped-graphene quantum dots
Authors: Gazizadeh Masoud , Dehghan Gholamreza , Soleymani Jafar
Published: August 2022

Shcematic representation of the MTF detection by an enhancing mechanism.
New dimeric chromanone derivatives from the mutant strains of Penicillium oxalicum and their bioactivities
Authors: Gu Guowei , Zhang Tao , Zhao Jianyuan , Zhao Wuli , Tang Yan , Wang Lu , Cen Shan , Yu Liyan , Zhang Dewu
Published: August 2022

Three new chromanone dimers, paecilins F–H (1–3) and ten known compounds (4–13), were obtained from the mutant strains of Penicillium oxalicum 114-2, and some of them showed significant antiviral activities.
Preparation, characterization and in vitro study of bellidifolin nano-micelles
Authors: Gao Fan , Chen Ziyue , Zhou Li , Xiao Xuefeng , Wang Lin , Liu Xingchao , Wang Chenggang , Guo Qiuhong
Published: August 2022

Bellidifolin (BEL), a xanthone compound, has significant therapeutic effectiveness in cardiac diseases such as arrhythmias.
A label-free strategy for visual genotyping based on phosphate induced coloration reaction
Authors: Zhang Jiaxing , Hui Hui , Xu Wei , Hua Kai , Cui Yali , Liu Xiaonan
Published: August 2022

Phosphate induced coloration reaction facilitates visual genotyping and the target variant can be accurately identified within 30 min from blood directly.
Visible light activated BINOL-derived chiroptical switches based on boron integrated hydrazone complexes
Authors: van Vliet Sven , Alachouzos Georgios , de Vries Folkert , Pfeifer Lukas , Feringa Ben L.
Published: August 2022

Chiroptical switches, which use light to control chirality in a reversible manner, offer unique properties and fascinating prospects in the areas of molecular responsive systems, new photochromic materials and molecular data processing and storage.
Tuning the polymer thermal conductivity through structural modification induced by MoS2 bilayers
Authors: Gharib-Zahedi Mohammad Reza , Koochaki Amin , Alaghemandi Mohammad
Published: August 2022

The present work refers to physical and structural study of nanoconfined polymers in polymer–MoS2 nanocomposites as a function of the MoS2–MoS2 interlayer distance. We have applied equilibrium and nonequilibrium MD calculations for PA and PS between MoS2 layers.
Packing core–corona particles on a spherical surface
Authors: Pérez-Figueroa S. E. , Gallegos-Lozano Andrés , Mendoza Carlos I.
Published: August 2022

Soft particles interacting through a hard-core square-shoulder potential, when confined on a spherical surface, self-assemble in a plethora of non-trivial structures.
Integration graph attention network and multi‐centre constrained loss for cross‐modality person re‐identification
Authors: He Di , Zhang Jingrui , Zhang Zhong , Liu Shuang , Durrani Tariq S.
Published: August 2022

Cross‐modality person re‐identification is a challenging task due to the large visual appearance difference between RGB and infrared images. Existing studies mainly focus on learning local features and ignore the correlation between local features. In this paper, the Integration Graph Attention Network is proposed to learn the completed correlation between local features via the graph structure. To this end, the authors learn the coarse‐fine attention weights to aggregate the local features by considering local detail and global information. Furthermore, the Multi‐Centre Constrained Loss is proposed to optimise the feature similarity by constraining the centres of modality and identity. It simultaneously utilises three kinds of centre constraints, that is intra‐identity centre constraint, modality centre constraint, and inter‐identity centre constraint, in order to reduce the influence of modality information explicitly. The proposed method is evaluated on two standard benchmark datasets, that is SYSU‐MM01 and RegDB, and the results demonstrate that the authors’ method achieves better performance than the state‐of‐the‐art methods, for example, surpassing NFS by 4.8% and 6.0% mAP on the single‐shot setting in All‐search and Indoor‐search modes, respectively.
Novel non‐linear control of DFIG and UPFC for transient stability increment of power system
Authors: Ghaedi Sadegh , Abazari Saeed , Arab Markadeh Gholamreza
Published: August 2022

This paper offers novel non‐linear control of a doubly fed induction generator (DFIG) and unified power flow controller (UPFC) for transient stability increment with transient energy function (TEF) and sliding mode observer in a power system. First, the TEF technique is considered for the damping control in a power system with a synchronous generator (SG), DFIG, and UPFC, and then the controller time‐derivative signals are estimated by a second‐order sliding mode observer. The importance of the issue is in the employ of a complete UPFC model. Also, a one‐axis model is used for DFIG that is similar to the SG model. Another characteristic of the novel non‐linear technique is robust versus system topology changes and variable time delay of the control signals. To evaluate the performance of the novel non‐linear control method for increment transient stability, simulation studies are performed on a two‐machine connected to an infinite bus (TMIB), the IEEE 9‐bus, and the New England Standard 39‐bus power system. The results determine that the novel non‐linear control method decreases the first swing of fluctuations admissibly and enhancement stability margins considerably.
Sub‐synchronous control interaction in power grids including doubly fed induction generator based wind turbines
Authors: Azizi Amir Hossein , Rahimi Mohsen
Published: August 2022

Integration of doubly‐fed induction generator (DFIG) based wind turbines (WTs), in series‐compensated power grids, may result in a phenomenon known as sub‐synchronous control interaction (SSCI). Indeed, SSCI, created due to interaction between WTs controllers and series‐compensated power grid, may worsen damping of sub‐synchronous resonance (SSR) oscillations. This paper deals with the analytical assessment and mitigation of SSCI phenomenon in series compensated grids comprising of DFIG‐based WTs. In this way, first, theoretical and mathematical expressions and equivalent circuits regarding the SSCI phenomenon and the impacts of the RSC and GSC controls on the SSR oscillations damping are given and then a comprehensive impedance model for the DFIG‐WT at the sub‐synchronous frequency is extracted. Next, the rotor current control is modified, and an efficient approach based on the feedback linearizing technique (FLT), different from approaches presented in the related literature, is presented to mitigate the negative role of the DFIG in SSR frequencies. By mathematical analyses and developing related formula, it is shown that the proposed approach changes the impedance of the rotor circuit to infinity at the SSR frequency. This in turn results in suppression of the SSR oscillations initiated as a result of induction generator effect and SSCI phenomenon.
Impact of climate change on site characteristics of eight major astronomical observatories using high-resolution global climate projections until 2050
Authors: Haslebacher C. , Demory M.-E. , Demory B.-O. , Sarazin M. , Vidale P. L.
Published: August 2022

Context.Sites for next-generation telescopes are chosen decades before the first light of a telescope. Site selection is usually based on recent measurements over a period that is too short to account for long-term changes in observing conditions such as those arising from anthropogenic climate change. For astronomical facilities with a typical lifetime of 30 yr, it is therefore essential to be aware of climate evolution to optimise observing time.

Aims.In this study, we analyse trends in astronomical observing conditions for eight sites. Most sites either already host telescopes that provide in situ measurements of weather parameters or are candidates for hosting next-generation telescopes. For a fine representation of orography, we use the highest resolution global climate model (GCM) ensemble available provided by the high-resolution model intercomparison project and developed as part of the European Union Horizon 2020 PRIMAVERA project.

Methods.We evaluate atmosphere-only and coupled PRIMAVERA GCM historical simulations against in situ measurements and the fifth generation atmospheric reanalysis (ERA5) of the European centre for medium-range weather forecasts for the period 1979–2014. The projections of changes in current site conditions are then analysed for the period 2015–2050 using PRIMAVERA future climate simulations.

Results.Over most sites, we find that PRIMAVERA GCMs show a good agreement in temperature, specific humidity, and precipitable water vapour compared to in situ observations and ERA5. The ability of PRIMAVERA to simulate those variables increases confidence in their projections. For those variables, the model ensemble projects an increasing trend for all sites, which will result in progressively poorer astronomical observing conditions compared to current conditions. On the other hand, no significant trends are projected for relative humidity, cloud cover, or astronomical seeing and PRIMAVERA does not simulate these variables well compared to observations and reanalyses. Therefore, there is little confidence in these projections.

Conclusions.Our results show that climate change will negatively impact the quality of astronomical observations and is likely to increase time lost due to bad site conditions. We stress that it is essential for astronomers to include long-term climate projections in their process for site selection and monitoring. We show that high-resolution GCMs can be used to analyse the effect of climate change on site characteristics of next-generation telescopes.
Effect of B2O3 on the structure and properties of aluminate slag
Authors: Zhang Chen , Kong Yu-qi , Wu Ting , Bao Guang-da , Lei Jie , Wang Hai-chuan
Published: August 2022

The spectral experiment, hemispherical melting point apparatus, rotating cylinder method, and four-probe method are conducted to measure the structure, melting temperature, apparent viscosity and electrical conductivity of aluminate slag. The results show that in order to reduce the comprehensive effect of capacitance and inductance, the frequency of value 6000 Hz corresponding to the minimum impedance is most suitable for the electrical conductivity measurement. Higher B2O3 content leads to a lower degree of polymerization, symmetry, and uniformity in the complex three-dimensional structure of the slag, meanwhile the slag hemispheric temperature declines gradually, which enhances the slag superheat, hence decreases the apparent viscosity and increases the electrical conductivity comprehensively, as well as the relation between viscosity logarithm and the conductivity logarithm at 1300 °C was linear. The breaking temperature of apparent viscosity-temperature curve reduces gradually with B2O3 addition, while the conductivity-temperature curve indicate that the slag crystallized at about 1210 to 1224 °C, and with the lower B2O3 content, the crystallization trend is more obvious.
First-principles study on yttrium inclusions in micro alloyed steels
Authors: Yang Changqiao , Liu Xiangjun , Yang Jichun , Yang Quanhai
Published: August 2022

The removal and control of inclusions has always been a hot issue in the field of metallurgy, and rare earth modifying is a proven method. However, some rare earth inclusions cannot be accurately judged due to the necessary assumptions for thermodynamic calculations and the lack of certain thermodynamic data. On the other hand, most of the currently reported researches focus on the changes in the morphology of the inclusions, and rarely involve the inherent properties of the inclusions. To address these two deficiencies, this work investigated elaborately the stability, elastic modulus, elastic anisotropy and thermal expansion coefficient of yttrium (Y) inclusions in micro alloyed steels by first-principles calculation. Then, the role of yttrium inclusion in the initial stage of crack initiation was discussed. The results showed that it was practical to judge the possibility of unknown inclusions formation in steel by formation enthalpy. The inclusions were changed from Al2O3 to Y2O3, Y2O2S, YAlO3-Y2Si2O7 composite inclusions with yttrium treatment, which was consistent with the metallographic observations. The bulk modulus (B), shear modulus (G), Young’s modulus (E), and Poisson’s ratio (σ) were calculated in a framework of the Voigte-Reusse-Hill approximation. In light of B/G and σ values, Al2O3 showed apparent brittleness, and the toughness of yttrium inclusions were improved to varying degrees compared to Al2O3 inclusions. Moreover, the order of the degree of elastic anisotropy for these inclusions was Y2Si2O7 > Al2O3 > Y2O3 > Y2O2S > YAlO3. Furthermore, the thermal expansion coefficient of Y2O3, Y2O2S, YAlO3 inclusions at any temperature were greater than that of Al2O3 and were relatively close to that of Fe, whereas, Y2Si2O7 inclusion was much larger than that of Fe. Finally, the difference between yttrium inclusions and iron matrix in the aspect of incompressibility, brittleness, toughness, mechanical anisotropy, and thermal expansion was reduced significantly, thereby improving the consistency of the matrix, this could be used to explain the phenomenon of alleviating stresses concentration and delaying the formation of micro voids.
Mathematical model of supersonic jet centerline velocity for multi-nozzle oxygen lance
Authors: Li Yanxin , Jia Hongbin , Liu Guangqiang , Liu Kun
Published: August 2022

The supersonic jet characteristics of multi-nozzle oxygen lance are the key to the quality of converter steelmaking. It is of great significance to clarify the velocity distribution characteristics of multi nozzle jet centerline to guide the production practice of converter steelmaking. Taking the oxygen lance for 260 t converter as the object, a three-dimensional geometric model is established to study the distribution characteristics of jet centerline velocity under different Mach number and inclination. The synergistic effect of Mach number and orifice inclination on jet attenuation is mainly studied. The mathematical expressions of jet deflection, Mach number and jet inclination are established, the calculation method of jet centerline deviation is proposed, and the previous mathematical model of jet centerline velocity is improved. The results show that the momentum transfer coefficient Kj
of multi-nozzle oxygen lance is not only related to Mach number, but also affected by jet inclination. The deviation between the corrected mathematical model and the field measured results is 4.3%.
Cause analysis of V-shaped crack pairs on drawn welding wire surface of ER70S-6 steel
Authors: Zhao Haitao , Wang Shuize , Gao Junheng , Qi Jianjun , Su Ru , Zhang Hongqi , Chen Hongwei , Tian Zhiqiang , Bai Lijuan
Published: August 2022

Welding wires are widely used as electrodes in various welding processes. To produce welding wires, wire rods are drawn gradually to final diameters at welding wire manufacturers. During the wire drawing process, premature failure happens frequently due to various reasons, and a type of wire drawing failure originated from wire surface V-shaped cracks or so-called chevron-like cracks is often found. In this research, V-shaped cracks on drawn welding wire surfaces of ER70S-6 steel were characterised carefully and its underlying mechanism was discussed thoroughly. It was found that the V-shaped cracks on wire surfaces are often present in pairs with opposite directions. Martensite microstructure was found nearby the V-shaped cracks, and its formation can be attributed to deteriorated local lubrication during wire drawing, which causes the austenitization of the wire surface and the subsequent formation of martensite. The large friction on wire surface induces the development of V-shaped cracks along the drawing direction. Meanwhile, as martensite is difficult to deform, strain localization happens in the ferrite/pearlite matrix, and V-shaped strain localization areas were found around the martensite, leading to the development of V-shaped cracks in the opposite direction of the drawing direction.
Gesundheitsbezogene Ziele der digitalen Prävention und
Gesundheitsförderung in Familien
Authors: Meixner Charlotte , Baumann Hannes , Wollesen Bettina
Published: August 2022

Ziel der Studie Digitale Technologien gewinnen in der primären
Prävention zunehmend an Bedeutung. Die Mehrheit digitaler Angebote
richtet sich an das Individuum; Zielgruppen wie Familien werden selten
adressiert, die Ermittlung und die Berücksichtigung des Bedarfs und der
Bedürfnisse sind für eine adressatengerechte Appentwicklung
bedeutend. Das Studienziel ist die Ermittlung der Grundvoraussetzungen und
gesundheitsbezogenen Ziele der befragten Familien für die
Handlungsfelder Bewegung, Ernährung und Entspannung sowie die Erfassung
inhaltlicher Schnittmengen der Familienmitglieder in einer Gesundheits-App.

Methodik Die Online-Befragung erfolgte mit N=1008 Elternteilen
(Ø 48 Jahre, 59% weiblich, 39,3% männlich,
1,7% divers) zu deren Gesundheitszustand sowie den Themen Bewegung,
Ernährung und Entspannung, Smartphonenutzung, Appfeatures und
Gamification. Die quantitative Datenauswertung (Häufigkeitsanalysen,
Chi2-Test, Faktorenanalyse sowie einfaktorielle Varianzanalyse) erfolgte mit IBM
SPSS Analytics (25; Armonk, NewYork).

Ergebnisse Der Gesundheitszustand wurde von der Mehrheit der Befragten als
positiv bewertet. Die Minderheit erfüllte die Referenzwerte der WHO in
der Bewegungsaktivität und Ernährung. Weiter berichteten die
Befragten über ein hohes Stresslevel und niedrige
Stressmanagementkompetenzen. Als Zielbereiche zur Gesundheitsförderung
ließen sich vor allem aktive Entspannungsmaßnahmen,
Ernährung, Kompetenzerweiterung, körperliche Aktivität,
Naturaktivitäten und Sport-Erholungsangebote identifizieren.
Signifikante Unterschiede für die Akzeptanz seitens der Kinder zeigten
sich mit steigendem Alter für die Bereiche aktive
Entspannungsmaßnahmen [F(2)=3,367; p=,035] und Sport- und
Erholungsangebote [F(2)=7,480; p=,001].

Schlussfolgerung Die Studie deckt inhaltliche Schnittpunkte der
Familienmitglieder für einen Prozess der gesundheitlichen
Verhaltensänderung mit digitaler Unterstützung auf. Das
Interesse an einzelnen Angeboten differiert zwischen den Altersgruppen der
Kinder. Weitere Forschung sollte Nutzungspräferenzen in einer
familiären Gesundheits-App, die Nutzung in verschiedenen
Familienkonstellationen sowie eine familiengerechte Ansprache
identifizieren.
The Mesentery—Past, Present, and Future
Authors: Coffey J. Calvin , Hohenberger W. , Heald R.
Published: August 2022

This article summarizes the events that shaped our current understanding of the mesentery and the abdomen. The story of how this evolved is intriguing at several levels. It speaks to considerable personal commitment on the part of the pioneers involved. It explains how scientific and clinical fields went different directions with respect to anatomy and clinical practice. It demonstrates that it is no longer acceptable to adhere unquestioningly to models of abdominal anatomy and surgery. The article concludes with a brief description of the Mesenteric Model of abdominal anatomy, and of how this now presents an opportunity to unify scientific and clinical approaches to the latter.
Mesentery in Transanal TME
Authors: Knol Joep , Chadi Sami A.
Published: August 2022

Oncological adequacy in rectal cancer surgery mandates not only a clear distal and circumferential resection margin but also resection of the entire ontogenetic mesorectal package. Incomplete removal of the mesentery is one of the commonest causes of local recurrences. The completeness of the resection is not only determined by tumor and patient related factors but also by the patient-tailored treatment selected by the multidisciplinary team. This is performed in the context of the technical ability and experience of the surgeon to ensure an optimal total mesorectal excision (TME). In TME, popularized by Professor Heald in the early 1980s as a sharp dissection through the avascular embryologic plane, the midline pedicle of tumor and mesorectum is separated from the surrounding, mostly paired structures of the retroperitoneum. Although TME significantly improved the oncological and functional results of rectal cancer surgery, the difficulty of the procedure is still mainly dependent on and determined by the dissection of the most distal part of the rectum and mesorectum. To overcome some of the limitations of working in the narrowest part of the pelvis, robotic and transanal surgery have been shown to improve the access and quality of resection in minimally invasive techniques. Whatever technique is chosen to perform a TME, embryologically derived planes and anatomical points of reference should be identified to guide the surgery. Standardization of the chosen technique, widespread education, and training of surgeons, as well as caseloads per surgeon, are important factors to optimize outcomes. In this article, we discuss the introduction of transanal TME, with emphasis on the mesentery, relevant anatomy, standard procedural steps, and importance of a training pathway.
Mapping the Mesentery Using ICG
Authors: Chand Manish , Dean Meara
Published: August 2022

Indocyanine green (ICG) fluorescent imaging has been used in colorectal surgery to assess intraoperative blood flow to the colon. However, its use has expanded to allow imaging of the lymphatic drainage within the mesentery in cancer resections. This technique can been used for real-time visualization of lymph nodes, and the detection of sentinel lymph nodes, lateral sidewall nodes, metastatic lymph nodes, and peritoneal metastases. Ultimately, this provides a more informative map of the mesentery displaying lymphatics and blood flow. The technique is economical and easy to use by the surgeon intraoperatively. ICG lymphangiography has the potential to aid the surgeon to ensure complete lymphadenectomy is performed in cancer resections.
What Drives Africa’s Inability to Comply with EU Standards? Insights from Africa’s Institution and Trade Facilitation Measures
Authors: Kareem Fatima Olanike , Martínez-Zarzoso Inmaculada , Brümmer Bernhard
Published: August 2022

Over the years, there have been a significant number of Africa’s food exports rejected at the European Union (EU) borders due to their non-compliance with EU food safety standards. This paper, therefore, provides an in-depth investigation of the potential causes of the non-compliance of Africa’s food exports to EU food standards and the subsequent rejection of such food exports at its borders. We contribute to the literature by investigating the roles played by trade facilitation measures and institutions in food export rejections and also exclusively provide a more detailed analysis and specific evidence at the product level. Our results indicate that poor trade facilitation measures, particularly inefficient border and food logistics procedures in African countries, increase the incidence of food rejection at the EU border and add to Africa’s challenges in accessing EU markets. Thus, non-compliance with EU food safety standards can be addressed by African governments through the strengthening of their domestic institutions and trade facilitation measures, with policies that improve logistics and border procedures as well as measures that align their food standards to international ones. This will ensure an efficient food supply chain that meets international food safety standards and facilitates food trade.
Employing the photothermal effect to improve water quality
Authors: Thompson Avery
Published: August 2022

Nb 2 CT x  MXene integrated few-mode fiber coupler identifies harmful antibiotic, commonly found in agricultural runoff, quickly and easily.
Wielding intermittency with cycle expansions
Authors: Cao Huanyu , Gao Ang , Zheng Haotian , Lan Yueheng
Published: August 2022

As periodic orbit theory works badly on computing the observable averages of dynamical systems with intermittency, we propose a scheme to cooperate with cycle expansion and perturbation theory so that we can deal with intermittent systems and compute the averages more precisely. The periodic orbit theory assumes that the shortest unstable periodic orbits build the framework of the system and provide cycle expansion to compute dynamical quantities based on them, while the perturbation theory can locally analyze the structure of dynamical systems. The dynamical averages may be obtained more precisely by combining the two techniques together. Based on the integrability near the marginal orbits and the hyperbolicity in the part away from the singularities in intermittent systems, the chief idea of this paper is to revise intermittent maps and maintain the natural measure produced by the original maps. We get the natural measure near the singularity through the Taylor expansions, and the periodic orbit theory captures the natural measure in the other parts of the phase space. We try this method on one-dimensional intermittent maps with single singularity, and more precise results are achieved.
Effects of rotating magnetic island on the transport of trapped fast ions
Authors: Zhao Jianhua , Cao Jinjia , Xiang Dong , Dai Yongzhi , Yang Junhui , Yang Wenjun
Published: August 2022

The enhanced transport of trapped energetic ions (TEIs) in the presence of resonant interactions between trapped fast ions and a rotating magnetic island is investigated within a drift-kinetic framework. Gyro-orbit banana center model equations of resonances between the island rotation, the bounce motion of trapped fast ions, and their precession frequency (poloidal precession and precession in the helical direction) are constructed. There are two solutions for resonances in phase space for different mode numbers, with only one solution having low-energy resonant lines (<100 keV); the other has not only low-energy resonant lines but also high-energy lines (≥100 keV). Island rotation plays an important role in the low-energy region, especially near the trapped-passing boundary. The precession frequency is more important when resonances occur in the high-energy area. Thus, the effect of islands on TEI transport in a low-energy region is the focus of this paper. Transport fluxes caused by collisions, resonances, and symmetry breaking induced by an island are obtained. We divide transport fluxes into two types: Γc arising from magnetic drift and Γb arising from the island rotation. There is a discontinuity in Γc with different island widths near the island separatrix. On the right-hand side of the (m = 2, n = 1) rational surface, Γc is more important than Γb, and at the plasma boundary, the flux due to drift can suppress Γb, which makes fast ions move toward inner plasma. On the left-hand side of the rational surface, Γb is dominant. When the island width is larger than a certain threshold, the fluxes oscillate, and Γb is far larger than Γc.
A global bifurcation organizing rhythmic activity in a coupled network
Authors: Medvedev Georgi S. , Mizuhara Matthew S. , Phillips Andrew
Published: August 2022

We study a system of coupled phase oscillators near a saddle-node on invariant circle bifurcation and driven by random intrinsic frequencies. Under the variation of control parameters, the system undergoes a phase transition changing the qualitative properties of collective dynamics. Using Ott–Antonsen reduction and geometric techniques for ordinary differential equations, we identify heteroclinic bifurcation in a family of vector fields on a cylinder, which explains the change in collective dynamics. Specifically, we show that heteroclinic bifurcation separates two topologically distinct families of limit cycles: contractible limit cycles before bifurcation from noncontractibile ones after bifurcation. Both families are stable for the model at hand.
An approximated volume of fluid method with the modified height function method in the simulation of surface tension driven flows
Authors: Liu Cheng , Gao Ruoqing , Hu Changhong
Published: August 2022

Surface tension in two-phase flow problems plays a dominant role in many micro-flow phenomena and has an important influence on the development of flow instability phenomena that contain free surfaces. In this study, the multi-moment finite volume method is extended for direct numerical simulation of two-phase flow problems. A constraint interpolation profile–CSL (semi-Lagrangian) scheme is used for discretization of the advection part in the momentum equation. A compact volume of fluid method–approximated piecewise linear calculation method without flux limiter is proposed for capturing the moving interface. For modeling the surface tension accurately, the logic in curvature estimation is redesigned based on the height function (HF) method. The isolated volumetric fractions that may reduce accuracy in HF integration are excluded, and the numerical solution shows that the accuracy in the curvature estimation is improved for a coarse mesh. The present method is implemented with a parallel block-structured adaptive mesh refinement (BAMR) strategy; thus, the computational cost can be reduced significantly. Numerical tests show that the present BAMR solver is capable of reproducing the theoretical predictions of capillary wave instability problems with high accuracy. The simulation of droplet collisions further demonstrates the accuracy of the surface tension model. Finally, we extend it to the liquid jet atomization. The wavy disturbance, film breakup, liquid filament pinch-off, and droplet generation are well reproduced. The droplet size distribution satisfies the experimental measurement and theoretical predictions power-law. BAMR shows a huge advantage in computational efficiency than the traditional Cartesian grid. The findings of this study can help for a better understanding of the micro-mechanism of surface tension driven flows.
Vortex and cavity dynamics for the tip-leakage cavitation over a hydrofoil
Authors: Qian Zhaohui , Wang Zhe , Geng Chen , Luo Xianwu
Published: August 2022

Large eddy simulations were used to investigate unsteady tip-leakage cavitating flow over a National Advisory Committee for Aeronautics 0009 hydrofoil. The proper orthogonal decomposition (POD) was combined with fast Fourier transforms to help better understand the deformation dynamics of the vortex and cavity. The results show three typical vortices, i.e., the tip-leakage vortex (TLV), tip-separation vortex (TSV), and shedding–trailing vortex (STV) with their own helical core lines in the averaged cavitating flows. Upstream of x/C = 1.8, the mean TLV core carries the breathing mode waves through the vortex dilatation effect, while the TSV core generates the dilatation, shrinkage, and bending distortions near the cavity interface by vortex stretching and deflection effects. Further downstream, the TLV starts to intertwine with the TSV, and the STV gradually diffuses. The TLV wandering encourages large cavity deformations dominated by the breathing and bending modes. However, in the lower-order POD modes, the contribution of bending modes to the cavity fluctuation energy is greatly weakened due to the variation of the relative cavity radius, r*, which indicates that the breathing mode and the double helix mode play major roles in the cavity interfacial waves. The results also show that the cavity interfacial oscillations are highly correlated with the surrounding velocity fluctuations. Moreover, a modified theoretical dispersion equation can well reproduce the quantitative relation between the vibration frequencies and the axial wavenumbers of the TLV cavity, especially for the wave dynamics of the breathing modes and the double helix modes.
Effect of small amount of CF4 addition on He and Ar atmospheric pressure plasma jet and influence of relative permittivity of downstream material on plasma–surface interaction
Authors: Liu Jie , Wang Lijun , Zhang Runming , Lian Zhuoxi , Wang Zhiwei
Published: August 2022

CF4 is an important source of fluorine groups in atmospheric pressure plasma jet (APPJ). In order to obtain reactive fluorine species under atmospheric pressure, noble gas (Ar or He) and CF4 are usually mixed and used as the working gas of APPJ. In this paper, the differences in the discharge dynamics on He/CF4 APPJ and Ar/CF4 APPJ are investigated experimentally. Meanwhile, combined with simulation, the effects of downstream targets with different relative permittivity on the radial propagation range of the plasma plume and the distribution of F-containing reactive species are studied. It is discovered that the addition of a small amount of CF4 (20 sccm) will increase the intensity of He/CF4 APPJ due to the contribution of Penning ionization of metastable He with CF4. Differently, the addition of CF4 will continuously lead to a significant decrease in the intensity of Ar/CF4 APPJ. The radial propagation range of He/CF4 APPJ on the target surface decreases with the increase in the relative permittivity of the downstream target. The smaller relative permittivity inhibits the axial propagation speed of APPJ, but it increases the radial propagation range of reactive species. The larger relative permittivity promotes the production of F-containing reactive species and their flux intensity on the target surface.
Transition volumes from multiply twinned particles to single crystals of supported Ag and Au nanoparticles
Authors: Chen Peiyu , Silly Fabien , Zhao Yingrui , Castell Martin R.
Published: August 2022

Shape changes of Ag and Au nanoparticles supported on single crystal reconstructed SrTiO3(001) and (111) substrates were investigated using scanning tunneling microscopy. Both metals nucleate as multiply twinned particles (MTPs) and transform into face-centered-cubic single crystals (SCs) beyond a critical volume. On SrTiO3(001)-c(4 × 2) the critical volumes are measured as 141 ± 51 nm3 for Ag and 107 ± 23 nm3 for Au, whereas on SrTiO3(111)–(4 × 4)+(6 × 6) the critical volumes are 53 ± 26 nm3 for Ag and 26 ± 40 nm3 for Au. A much larger transition volume was observed on SrTiO3(001)–(2 × 1), where Ag remains as MTPs up to 3400 nm3, while Au nucleates as atomic monolayers instead of MTPs. This work demonstrates the significant impact of small variations of the surface structure of the substrate on the MTP–SC transition volume.
Simulating single-particle dynamics in magnetized plasmas: The RMF code
Authors: Glasser A. H. , Cohen S. A.
Published: August 2022

The RMF (Rotating Magnetic Field) code is designed to calculate the motion of a charged particle in a given electromagnetic field. It integrates Hamilton’s equations in cylindrical coordinates using an adaptive predictor-corrector double-precision variable-coefficient ordinary differential equation solver for speed and accuracy. RMF has multiple capabilities for the field. Particle motion is initialized by specifying the position and velocity vectors. The six-dimensional state vector and derived quantities are saved as functions of time. A post-processing graphics code, XDRAW, is used on the stored output to plot up to 12 windows of any two quantities using different colors to denote successive time intervals. Multiple cases of RMF may be run in parallel and perform data mining on the results. Recent features are a synthetic diagnostic for simulating the observations of charge-exchange-neutral energy distributions and RF grids to explore a Fermi acceleration parallel to static magnetic fields.
Two models and the generation mechanisms of the drag on an accelerating starting disk
Authors: Li Zhuoqi , Xiang Yang , Qin Suyang , Liu Hong , Wang Fuxin
Published: August 2022

As a canonical problem, the impulsive starting of a circular disk contains the fundamental mechanisms of the force generation of the drag-based propulsions. In this paper, a circular disk is uniformly accelerated to a constant target velocity along a straight path, the instantaneous drag on and the flow fields around the disk are measured. A series of experiments were conducted by varying the two dimensionless numbers, i.e., the Reynolds number (Re) ranging from 40 000 to 80 000 and the acceleration number (A*) (double normalized uniform-acceleration distance) ranging from 0.5 to 2. Based on the quasi-steady and the impulse-based ideas, two analytical models are proposed for predicting and accounting for the drag force on the disk. Moreover, the two models distinguish the generation of the drag force into three phases. In the acceleration phase, the growth rate and initial peak of the drag on the disk strongly depend on A*, which make the drag-force histories exhibit a good scaling law for a given A*, and the whole drag is generally contributed by the increased growth rate of the vortex ring circulation. In the transition phase, the drag decreases owing to the decrease in the circulation growth rate of the vortex ring. In the vortex pinch-off phase, the circulation of the vortex ring nearly no longer grows and the size growth rate of vortex ring gradually plays a dominant role in the drag generation. The present results suggest two implications. The peak of the drag in the accelerating phase implies an alternative perspective for understanding the high-lift generation in the reversal of wing stroke in flapping flight, and three-phase drag generation implies a controllable principle based on vortex formation for enhancing the force generation in drag-based propulsions.
Real-time detection of viruses in aerosols with weak light imaging based on Tesla discharge
Authors: Li Zuxin , Xia Chengming , Tian Yi , Zhang Beilei , Zhou Wan , Liu Na , Wei Qiao , Li Jinzhong , Chen Cong , Chen Linhua , Wang Zhuo , Sun Yan , Li Chang , Yang Dong , Yu Wangyang , Liu Meng , Dai Jiapei
Published: August 2022

The analysis and detection of nucleic acid and specific antigens and antibodies are the most basic technologies for virus monitoring. However, the potential window for applying these technologies exists within a late specific period in the early monitoring and control of unknown viruses, especially human and animal pathogenic viruses transmitted via aerosols, e.g., SARS-CoV-2 and its variants. This is because early, real-time, and convenient monitoring of unknown viruses in the air or exhaled gas cannot be directly achieved through existing technologies. Herein, we report a weak light spectral imaging technology based on Tesla discharge (termed T-DAI) that can quickly monitor for viruses in real time in simulated aerosols with 71% sensitivity and 76% specificity for aerosol virus concentrations exceeding approximately 2800 vp/μl. This technology realizes the rapid detection of low concentrations of viruses in aerosols and could provide an important means for predicting, screening, and monitoring unknown or pandemic pathogenic viruses in the air or exhaled breath of humans and animals.
Is the Felixer cat control device safe for marsupial carnivores?
Authors: Rickards Holly , Read John L. , Johnson Chris N. , Jones Menna E. , Pauza Matthew D. , Bentley Joss , Sculthorpe Andry , Humphrey Morgan , Hamer Rowena
Published: August 2022

Context The Felixer grooming device (‘Felixer’) is a lethal method of feral cat control designed to be cost-effective and target specific. Aims This study aims to test the target specificity of the Felixer in Tasmania, with a particular focus on Tasmanian devil and quoll species due to the overlap in size, habitats and behaviour between these native carnivores and feral cats. Methods Our study deployed Felixer devices set in a non-lethal mode in nine field sites in Tasmania, one field site in New South Wales and two Tasmanian wildlife sanctuaries. Key results Our study recorded 4376 passes by identifiable vertebrate species including 528 Tasmanian devil passes, 507 spotted-tailed quoll passes and 154 eastern quoll passes. Our data showed that the Felixer can successfully differentiate quoll species from feral cats with spotted-tailed quolls and eastern quolls targeted in 0.19% and 0% of passes, respectively. However, Tasmanian devils and common wombats were targeted in 23.10% and 12% of passes, respectively, although sample size was low for common wombats (n = 25). Conclusions The Felixer could not reliably identify Tasmanian devils and possibly common wombats as non-target species. Further data is needed to confirm the potential for impacts on the common wombat and other potential non-target species in Tasmania, and the likelihood of the toxin being ingested by falsely targeted individuals. Implications Our study suggest that the Felixer device is safe for use in the presence of two species of conservation concern, the eastern and spotted-tailed quoll. It also supports evidence from previous studies that the Felixer is unlikely to impact bettongs and potoroos. Use of Felixer devices across much of Tasmania would have to balance the conservation or economic benefits of cat control against potential impacts on Tasmanian devils. We suggest that active Felixer deployments be preceded by surveys to establish the range of species present at the control site, and the season of control considered carefully to minimise potential impacts on more susceptible juvenile animals. In addition, modifications to the Felixer device such as the proposed incorporation of AI technology should be tested against the Tasmanian devil and other non-target species.
Salmonella
control in pork: effect of animal nutrition and feeding
Authors: Coma J.
Published: August 2022

The control of
Salmonella
prevalence in pork production is important from food safety, trading and animal health standpoints. Contamination by
Salmonella
can happen at any stage of the pork production chain: raw materials used in animal nutrition, feed manufacturing, farm level, slaughter plant, deboning room, meat processing, retail and preparation of meat at home. For this reason, a
Salmonella
control programme requires effort at all levels of the production chain. Animal feeding plays an essential role in
Salmonella
control because it might be a potential carrier and infection source, and also because effective measures can be applied at this stage to control bacterial transmission. The microbiological hygiene of feed is a requirement in a
Salmonella
control programme.
Salmonella
control in feed manufacturing embraces the following procedures: (1) Prevent or minimize the introduction of
Salmonella
through contaminated raw materials; (2) Implement decontamination steps: chemical and/or thermal treatments; (3) Prevent recontamination: microbiological hygiene of equipment and facilities in the feed mill and transportation. On the other hand, specific feeding systems positively affect the equilibrium of gut microbial ecology and contribute to the reduction of
Salmonella
prevalence. The combination of pre- and post-harvesting actions will ensure maximum food safety of pork.
Current distribution and status of
Lantana camara
and its biological control agents in Australia, with recommendations for further biocontrol introductions into other countries
Authors: Day M. D. , Broughton S. , Hannan-Jones M. A.
Published: August 2022

The results of surveys conducted in Australia over a five-year period (1996-2001) to determine the distribution of
Lantana camara
(lantana) and its introduced biological control agents are reviewed and discussed. The relative merits and drawbacks of each species are summarized for the benefit of other countries wishing to consider biological control programmes against lantana. Lantana is found in coastal and sub-coastal areas from far-north Queensland to southern New South Wales (NSW), Australia. Small populations of the weed have been reported around Darwin in the Northern Territory and Perth in Western Australia. For the purpose of this review, lantana is classified into five varietal groups, based on flower colour. The pink flowering group is the most common and widespread. It is the only variety found in southern NSW and in high altitude subtropical areas. The pink-edged red flowering varietal group is the next most common, being found from central NSW to far-north Queensland. The three remaining varietal groups, red, white and orange, are less common and limited in their distribution. Of the 30 biological control agents that have been introduced into Australia, 16 have established. The most widespread and damaging agents are
Octotoma scabripennis
,
Uroplata girardi
, and
Teleonemia scrupulosa
.
Leptobyrsa decora
is very damaging to lantana seasonally but has a very limited distribution, being found at only a few sites in high altitude tropical regions. Two agents,
Plagiohammus spinipennis
and
Teleonemia harleyi
previously reported as established, were not found in the surveys. Despite the establishment of 16 agents, lantana is not under adequate control in Australia. Climate is probably the major factor that prevents populations of insects from being maintained at consistently high enough levels to control the weed.