bluuebunny/crossref_metadata_2025_split huggingface dataset:
Habitat‐dependent impacts of exotic plant invasions on benthic food webs in a coastal wetland
Authors: Wang Sikai , He Qiang , Zhang Youzheng , Sheng Qiang , Li Bo , Wu Jihua 
Published: December 2020

AbstractExotic plants with wide ecological niches often invade multiple types of habitats, leading to homogenization of ecosystem structure and functions. How exotic plant invasions affect the structure and functions of benthic food webs in different habitats is poorly understood. We tested how Spartina alterniflora invasions affected benthic food webs in four contrasting types of habitat (Scirpus mariqueter marshes, Phragmites australis marshes, unvegetated tidal creeks, and bare tidal flats) in the Yangtze estuary. We examined distribution pattern of benthic macroinvertebrates, and documented the differences in basal resources of benthic food web by stable isotope analyses of δ13C and δ15N in different habitats. Our results showed that in unvegetated habitats, conversion of tidal creeks and bare tidal flats to exotic marshes following Spartina invasions significantly altered the functional composition of benthic food webs, which was driven partially by bottom‐up processes related to a consumer dietary shift from benthic organic matter to detritus (trophic effect) and by alteration in species composition related to habitat changes (nontrophic effect). In vegetated native habitats, while the replacement of native plants by Spartina consistently led to a shift in consumer diet from benthic organic matter to detritus, it did not significantly alter the functional composition of benthic food webs. These data suggested the relative importance of trophic and nontrophic effects of plant invasions on benthic food webs could vary with habitat structure (e.g., the presence of native vegetation). Our study provides new insights into the mechanisms underlying homogenization of ecosystem structure and functions by exotic plant invasions.
Winter in two phases: Long‐term study of a shallow reservoir in winter
Authors: Cavaliere Emily , Baulch Helen M. 
Published: December 2020

AbstractClimate‐driven decreases in ice‐cover duration have the potential to impact lake ecosystems, yet we have only partial understanding of the effects of winter conditions on physical, chemical, and biological properties of lakes. We used 39 years of monitoring data to examine under‐ice changes in nutrients, oxygen, and phytoplankton in a shallow drinking‐water reservoir. Two phases of winter were identified. Early winter was characterized by declining oxygen. In this phase, there were increases in specific conductance and concentrations of ammonium (‐N) and soluble reactive phosphorus (SRP). In the month prior to ice off these trends reversed themselves and phytoplankton began to increase. Specific conductance declined as meltwater entered the lake. Nutrients (SRP and ‐N) declined, concurrent with increases in chlorophyll a and oxygen during late winter. This work demonstrates that chemical and biotic changes through winter are highly time dependent and differ between early and late winter phases. The late winter phase is often unstudied because of unsafe ice conditions, but here, the “spring” bloom commonly occurs in late winter under ice. The phases of winter, which are likely driven by changes in light, must be considered as we work to understand how diverse lakes will respond to declining periods of ice cover, and what drives differences in the spring ecology of diverse ice‐covered lakes.
Long‐term intercomparison of two pCO2 instruments based on ship‐of‐opportunity measurements in a dynamic shelf sea environment
Authors: Macovei Vlad A. , Voynova Yoana G. , Becker Meike , Triest Jack , Petersen Wilhelm 
Published: December 2020

AbstractThe partial pressure of carbon dioxide (pCO2) in surface seawater is an important biogeochemical variable because, together with the pCO2 in the atmosphere, it determines the direction of air–sea carbon dioxide exchange. Large‐scale observations of pCO2 are facilitated by Ships‐of‐Opportunity (SOOP‐CO2) equipped with underway measuring instruments. The need for expanding the observation capacity and the challenges involving the sustainability and maintenance of traditional equilibrator systems led the community toward developing simpler and more autonomous systems. Here we performed a comparison between a membrane‐based sensor and a showerhead equilibration sensor installed on two SOOP‐CO2 between 2013 and 2018. We identified time‐ and space‐adequate crossovers in the Skagerrak Strait, where the two ship routes often crossed. We found a mean total difference of 1.5 ± 10.6 μatm and a root mean square error of 11 μatm. The pCO2 values recorded by the two instruments showed a strong linear correlation with a coefficient of 0.91 and a slope of 1.07 (± 0.14), despite the dynamic nature of the environment and the difficulty of comparing measurements from two different vessels. The membrane‐based sensor was integrated with a FerryBox system on a ship with a high sampling frequency in the study area. We showed the strength of having a sensor‐based network with a high spatial coverage that can be validated against conventional SOOP‐CO2 methods. Proving the validity of membrane‐based sensors in coastal and continental shelf seas and using the higher frequency measurements they provide can enable a thorough characterization of pCO2 variability in these dynamic environments.
Scratch‐Healing Surface‐Attached Coatings from Metallo‐Supramolecular Polymer Conetworks
Authors: Mugemana Clément , Martin Anouk , Grysan Patrick , Dieden Reiner , Ruch David , Dubois Philippe 
Published: December 2020

AbstractSelf‐healing polymer coatings have gained increased attention as a pathway for regenerating the inherent properties of surface following mechanical, physical or chemical damages. In most cases, the adhesion between the polymer coating layer and the substrate is driven by physical interactions. For some applications, immersing the polymer coating under water or exposing the coating to organic solvent vapors will undoubtedly lead to the coating delamination. One way to circumvent this issue is to attach the coating to the substrate via covalent bonds. However, this process will impede the self‐healing feature of the polymer coating due to the confinement of the volume change of the polymer to one dimension. Herein, surface‐attached metallo‐supramolecular polymer conetwork coatings are reported. The ability of the polymer conetworks to swell in organic solvent while maintaining their dimensional stability combined with reversible supramolecular cross‐links based on metal complexes enables the design of scratch‐healing polymer coatings. These metallo‐supramolecular polymer conetworks are prepared in a three‐step UV‐initiated polymerization reaction starting from the poly(pentafluorophenyl acrylate)‐l‐polydimethylsiloxane (PPFPA‐l‐PDMS)‐activated ester covalently attached to the substrate. Reacting the polymer conetwork coating with the 4‐(2‐aminoethyl)pyridine and cross‐linking the pyridine phases with ZnCl2 lead to the poly(N‐(2(pyridin‐4‐yl)ethyl)acrylamide‐Zn(II))‐l‐polydimethylsiloxane (PNP4EA‐Zn(II)‐l‐PDMS) polymer conetwork coatings with scratch‐healing ability.
Dispersion at Single Unit TiO2 Nanoparticles Reduced Tg, Induced Chain Disentanglement and Reduced Tensile Modulus in Waterborne Acrylic Coatings
Authors: Romo‐Uribe Angel 
Published: December 2020

AbstractSpatially distributed TiO2 nanoparticles induced an order of magnitude decrease of glass transition temperature, Tg, and chain disentanglement in waterborne acrylic coatings. Acrylic/TiO2 coatings are synthesized in situ by batch emulsion polymerization. The copolymer is based on butyl acrylate (BA), methyl methacrylate (MMA), and acrylic acid (AA) with composition 56:42:2 mol%, and nano‐TiO2 (ca. 12 nm) is incorporated up to 3 wt% content. Transmission electron microscopy (TEM) showed that TiO2 is dispersed at nearly single unit throughout the acrylic matrix. The nanoparticle reduced Tg and broadened the temperature range of the glass transition, δTg. The considerable increase of δTg suggests gradients of dynamics. Shear rheometry demonstrated that TiO2 induced chain disentanglement, the rubbery modulus Ge decreased two orders of magnitude with only 1 wt% TiO2 content thus increasing the packing length p (and the reptation tube diameter as dt = kp, k > 1). Consequently, the tensile Young's modulus E decreased an order of magnitude, relative to the neat copolymer. The reduction of Tg, the slowdown of macromolecular dynamics, the chain disentanglement and the increase of dt suggests dynamics modification due to intercalation of the entangled web by the TiO2 nanoparticles, and these results may be ascribed to a nanoconfinement effect.
Improvement of shielding measurement for small‐sized enclosures with consideration to the shielding quality of antenna cables
Authors: Hwang Jung‐Hwan , Hyoung Chang Hee , Kwon Jong Hwa , Park Hyun Ho 
Published: December 2020

AbstractThis article presents an improvement to IEEE 299.1 standard used to measure the shielding effectiveness (SE) of small‐sized metallic enclosures in a reverberation chamber. The shielding quality of radio‐frequency (RF) cables used for SE measurement significantly affects measurement accuracy, especially when metallic enclosures have a high level of SE. A new measurement parameter is introduced to represent a measurable range in which SE can be measured without being affected by the shielding quality of the RF cables. The proposed parameter can be effectively used for the IEEE 299.1‐based SE measurement method to improve measurement accuracy. In our experiments, the utilization of the proposed parameter confirms that the IEEE 299.1 method can measure SE of 87.5 dB up to 4 GHz. Furthermore, to reduce coupled noise through the antenna cable, three different methods are applied together during the shielding measurement of a high‐SE enclosure. Our experimental results show that these methods extend the measurable SE range up to 95 dB at frequencies below 4 GHz.
Determination of tautomeric preference of fenobam in solution by high‐resolution NMR spectroscopy
Authors: Sha Xuming , Chen Shaodong , Zheng Xiaojing , Ye Xin , Zhang Hailu , Huang Shaohua 
Published: December 2020

AbstractIn this work, tautomeric preference of fenobam in solution was investigated by homonuclear and heteronuclear solution nuclear magnetic resonance (NMR) spectroscopy. 1H–1H nuclear Overhauser effect spectroscopy (NOESY) spectrum revealed that fenobam in liquid state exists exclusively in one of the two possible tautomeric structures, which was confirmed by 1H–13C HSQC and heteronuclear multiple bond correlation (HMBC) spectra. Moreover, difference between the two tautomeric structures was studied by theoretical calculations, which further proved the result obtained by the NMR experiments.
Cell‐mediated immunity to SARS‐CoV‐2
Authors: Wang Xiaolin , Gui Jingang 
Published: December 2020

ABSTRACTSevere acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) viruses spread unscrupulously virtually every corner on the planet in a very quick speed leading to an unprecedented world pandemic of COVID‐19 claiming a great many of people’s life. Paramount importance has been given to the studies on the virus itself including genomic variation and viron structure, as well as cell entry pathway and tissue residence. Other than that, to learn the main characteristic of host immunity responding to SARS‐CoV‐2 infection is an eminent task for restraining virus and controlling disease progress. Beside antibody production in response to SARS‐CoV‐2 infection, host cellular immunity plays an indispensable role in impeding virus replication and expansion at various stages of COVID‐19 disease. In this review, we summarized the recent knowledge regarding the aberrant regulation and dysfunction of multiple immune cells during SARS‐CoV‐2 infection. This includes the dysregulation of immune cell number, Th polarity, cytokine storm they implicated with, as well as cell function exhaustion after chronic virus stimulation. Notwithstanding that many obstacles remain to be overcome, studies on immunotherapy for COVID‐19 treatment based on the known features of host immunity in response to SARS‐CoV‐2 infection offer us tangible benefits and hope for making this SARS‐CoV‐2 pandemic under control.
Reduced adenosine diphosphate sensitivity in skeletal muscle mitochondria increases reactive oxygen species production in mouse models of aging and oxidative stress but not denervation
Authors: Pharaoh Gavin , Brown Jacob , Ranjit Rojina , Ungvari Zoltan , Van Remmen Holly 
Published: December 2020

AbstractBackgroundMitochondrial bioenergetics are sensitive to adenosine diphosphate (ADP) concentration. Reactive oxygen species (ROS) production and respiration [oxygen consumption rate (OCR)] are altered at physiological ADP concentrations (i.e. ADP insensitivity) in aged human muscle. Here, we investigate ADP sensitivity in mouse muscle mitochondria.MethodsWe measured OCR and ROS production in permeabilized gastrocnemius fibres using an ADP titration protocol and the Oroboros O2k respirometer and fluorometer. We measured changes in ADP sensitivity in muscle from mice at different ages, after sciatic nerve transection (denervation), and in response to increased oxidative stress (Sod1−/− mice). Further, we asked whether the mitochondrial‐targeted peptide SS‐31 can modulate ADP insensitivity and contractile function in the Sod1−/− mouse model.ResultsReduced ADP sensitivity is associated with increases in mitochondrial ROS production in aged (62%) and Sod1−/− (33%) mice. The maximal capacity to produce ROS does not increase with age, and there is no effect of age on ADP sensitivity for OCR in mouse gastrocnemii. Denervation does not induce ADP insensitivity for either ROS generation or OCR. Treatment of Sod1−/− mice with SS‐31 increases ADP sensitivity for both OCR and ROS, decreases maximal ROS production (~40%), and improves resistance to muscle fatigue.ConclusionsAdenosine diphosphate sensitivity for ROS production decreases in aged mouse gastrocnemius muscle fibres, although aged mice do not exhibit a difference in OCR. Denervation does not induce ADP insensitivity; however, insensitivity to ADP is induced in a model of oxidative stress. ADP insensitivity could contribute to muscle fatigue, and SS‐31 may be the first drug capable of targeting this aging phenotype.
Finite‐time extended state observer‐based exact tracking control of an unmanned surface vehicle
Authors: Wang Ning , Zhu Zhongben , Qin Hongde , Deng Zhongchao , Sun Yanchao 
Published: December 2020

AbstractIn the presence of complex unknowns consisting of system dynamics and environmental disturbances, it is rather meaningful to exactly track an unmanned surface vehicle (USV) to the desired trajectory in practical scenarios including routing inspection, marine survey, and guard patrol, etc. In this paper, the exact trajectory tracking problem is solved by establishing a finite‐time extended state observer‐ (FESO) based exact tracking control (FESO‐ETC) scheme. By virtue of nonsmooth analysis, the FESO is firstly devised by only requiring continuous differentiability and is incorporated into the nonsingular fast terminal sliding mode control framework, and thereby further enhancing disturbance rejection and tracking accuracy. Moreover, global finite‐time stability of the entire FESO‐ETC closed‐loop system is derived from rigorously theoretical analysis, and thereby contributing to a model‐free finite‐time control paradigm. Simulation studies and comparisons demonstrate that the proposed FESO‐ETC approach can achieve exact trajectory tracking in the presence of complex unknowns.
On Bollobás‐Riordan random pairing model of preferential attachment graph
Authors: Pittel Boris 
Published: December 2020

AbstractBollobás‐Riordan random pairing model of a preferential attachment graph is studied. Let {Wj}j ≤ mn + 1 be the process of sums of independent exponentials with mean 1. We prove that the degrees of the first vertices are jointly, and uniformly, asymptotic to , and that with high probability (whp) the smallest of these degrees is , at least. Next we bound the probability that there exists a pair of large vertex sets without connecting edges, and apply the bound to several special cases. We propose to measure an influence of a vertex v by the size of a maximal recursive tree (max‐tree) rooted at v. We show that whp the set of the first vertices does not contain a max‐tree, and the largest max‐tree has size of order n. We prove that, for m > 1, . We show that the distribution of scaled size of a generic max‐tree in converges to a mixture of two beta distributions.
Mass Fabrication of 3D Silicon Nano‐/Microstructures by Fab‐Free Process Using Tip‐Based Lithography
Authors: Jo Jeong‐Sik , Choi Jihoon , Lee Seung‐Hoon , Song Changhoon , Noh Heeso , Jang Jae‐Won 
Published: December 2020

AbstractMethods for the mass fabrication of 3D silicon (Si) microstructures with a 100 nm resolution are developed using scanning probe lithography (SPL) combined with metal‐assisted chemical etching (MACE). Protruding Si structures, including Si nanowires of over 10 µm in length and atypical shaped Si nano‐ and micropillars, are obtained via the MACE of a patterned gold film (negative tone) on Si substrates by dip‐pen nanolithography (DPN) with polymer or by nanoshaving alkanethiol self‐assembled monolayers (SAMs). Furthermore, recessed Si structures with arbitrary patterning and channels less than 160 nm wide and hundreds of nanometers in depth are obtained via the MACE of a patterned gold film (positive tone) on Si substrates by alkanethiol DPN. As an example of applications using protruded Si structures, nanoimprinting in an area of up to a centimeter is demonstrated through 1D and 2D SPL combined with MACE. Similarly, submicrometer polydimethylsiloxane (PDMS) stamps are employed over millimeter‐scale areas for applications using recessed Si structures. In particular, the mass production of arbitrarily shaped Si microparticles at submicrometer resolution is developed using silicon‐on‐insulator substrates, as demonstrated using optical microresonators, surface‐enhanced Raman scattering templates, and smart microparticles for fluorescence signal coding.
Adhesion Enhancement of Micropillar Array by Combining the Adhesive Design from Gecko and Tree Frog
Authors: Liu Quan , Tan Di , Meng Fandong , Yang Baisong , Shi Zhekun , Wang Xin , Li Qian , Nie Chang , Liu Sheng , Xue Longjian 
Published: December 2020

AbstractIt has long been demonstrated the gecko‐inspired micropillar array with T‐shape tips possesses the best adhesion performance of a given material. The further enhancement of the adhesion performances of T‐shape micropillars can offer redundant adhesion to compensate for the inevitable improper contacts. Here, the array of T‐shape polydimethylsiloxane (PDMS) micropillars is incorporated with gradient dispersed calcium carbonate nanoparticles in the micropillar stalk, termed as T‐shape gradient micropillars (TG), possessing the modulus gradient with stiff tip and soft root. The gradient modulus in TG facilitates the contact formation and regulates the stress at the detaching interface, resulting in a 4.6 times adhesion and 2.4 times friction as compared with the pure PDMS T‐shape micropillar arrays. The study here provides a new design strategy for the super‐strong structured dry adhesives.
VO2 Nanostructures for Batteries and Supercapacitors: A Review
Authors: Khan Ziyauddin , Singh Prem , Ansari Sajid Ali , Manippady Sai Rashmi , Jaiswal Amit , Saxena Manav 
Published: December 2020

AbstractVanadium dioxide (VO2) received tremendous interest lately due to its unique structural, electronic, and optoelectronic properties. VO2 has been extensively used in electrochromic displays and memristors and its VO2 (B) polymorph is extensively utilized as electrode material in energy storage applications. More studies are focused on VO2 (B) nanostructures which displayed different energy storage behavior than the bulk VO2. The present review provides a systematic overview of the progress in VO2 nanostructures syntheses and its application in energy storage devices. Herein, a general introduction, discussion about crystal structure, and syntheses of a variety of nanostructures such as nanowires, nanorods, nanobelts, nanotubes, carambola shaped, etc. are summarized. The energy storage application of VO2 nanostructure and its composites are also described in detail and categorically, e.g. Li‐ion battery, Na‐ion battery, and supercapacitors. The current status and challenges associated with VO2 nanostructures are reported. Finally, light has been shed for the overall performance improvement of VO2 nanostructure as potential electrode material for future application.
The Characterization of Electronic Noise in the Charge Transport through Single‐Molecule Junctions
Authors: Yuan Saisai , Gao Tengyang , Cao Wenqiang , Pan Zhichao , Liu Junyang , Shi Jia , Hong Wenjing 
Published: December 2020

AbstractWith the goal of creating single‐molecule devices and integrating them into circuits, the emergence of single‐molecule electronics provides various techniques for the fabrication of single‐molecule junctions and the investigation of charge transport through such junctions. Among the techniques for characterization of charge transport through molecular junctions, electronic noise characterization is an effective strategy with which issues from molecule–electrode interfaces, mechanisms of charge transport, and changes in junction configurations are studied. Electronic noise analysis in single‐molecule junctions can be used to identify molecular conformations and even monitor reaction kinetics. This review summarizes the various types of electronic noise that have been characterized during single‐molecule electrical detection, including the functions of random telegraph signal (RTS) noise, flicker noise, shot noise, and their corresponding applications, which provide some guidelines for the future application of these techniques to problems of charge transport through single‐molecule junctions.
Forensic age estimation in migrants: Where do we stand?
Authors: Lossois Maisy , Baccino Eric 
Published: December 2020

AbstractMany countries have to respond to an influx of an increased number of refugees and asylum seekers, whose management depends on if they are minors. The age estimation, including forensic opinion, is complex and has serious implications. Several guidelines were published, in particular by The Study Group on Forensic Age Diagnostics of the German Association of Forensic Medicine (Schmeling et al., 2008, 2016). Forensic age estimation must contain, at first, an investigation into the medical history of the individual, to identify diseases or treatments that could interfere with growth. The skeletal development is, along with the dental development, the most important criterion for this estimation. For the skeleton, we use the comparison of hand and wrist radiographs with the atlas of Greulich and Pyle (Greulich, 1959), and the Schmeling's method (Kellinghaus et al., 2010) with a CT‐scan of the medial extremity of the clavicle, defining stages, and substages of ossification according to Kellinghaus et al. Dental imaging allows an evaluation of the stage of development of the crown and root, using Demirjian's stages (Demirjian et al., 1973). These methods are minimally irradiating, which is essential as they are used for a nonmedical goal. We know that, even using multiple methods, it is impossible to define a precise age, due to variability among the individuals and their respective origins. The results have to be expressed as minimum age, and the mean age with standard deviations. The majority and the claimed age have to be addressed. It is necessary to have a multidisciplinary evaluation carried out by qualified individuals.This article is categorized under:
Forensic Anthropology > Age Assessment