bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the effects of embedding resins on carbonate stable and clumped isotope analyses
Authors: Guo Jingjing , Zong Xiulan , de Winter Niels J. , Goudsmit‐Harzevoort Barbara , Peterse Francien , Ziegler Martin 
Published: July 2023

RationaleEmbedding resins are widely used to fix carbonates for high‐precision sample preparation and high‐resolution sampling. However, these embedding materials are difficult to remove after sample preparation and are known to affect the accuracy of carbonate stable isotope analyses. Nevertheless, their impact on clumped isotope analysis, which is particularly sensitive to contamination artifacts, has so far not been tested. The observation that running resin‐containing samples decreased the reproducibility of clumped isotope values for internal laboratory carbonate standards and increased the external standard deviation (SD 0.061–0.088‰) compared to the long‐term observations (0.034‰), prompted us to set up an experiment to test the influence of resin addition on instrument performance.MethodsHere we analyzed the stable and clumped isotope composition of a pure calcium carbonate standard (ETH‐4) mixed with three types of embedding resins in 2:1 and 1:1 proportions. Our aim was to assess how resin addition affects isotope analyses.ResultsWe found that none of the stable isotopic values were significantly different. The δ13C values were −10.22 ± 0.07‰ (mean ± SD) for pure ETH‐4, while the δ13C values of ETH‐4 mixed with embedding resins in 2:1 and 1:1 proportions were −10.21 ± 0.06‰ and −10.18 ± 0.06‰, respectively (p > 0.05). The δ18O values were −18.82 ± 0.11‰ for pure ETH‐4 versus −18.81 ± 0.09‰ and −18.82 ± 0.08‰ for 2:1 and 1:1 ETH‐4:resin mixtures, respectively (p > 0.05). Given the large uncertainty in our results, we did not find significant differences between different mixtures in the carbonate clumped isotope values (Δ47), with 0.458 ± 0.107‰, 0.464 ± 0.086‰, and 0.417 ± 0.089‰ in pure ETH‐4 and ETH‐4 with 2:1 and 1:1 resin mixtures, respectively (p > 0.05). However, a resin‐related bias in the results might be masked by the large uncertainty. The measured ETH‐4 values in our study are similar to the InterCarb values (δ13C = −10.20‰, δ18O = −18.81‰, Δ47 = 0.450‰, InterCarb‐Carbon Dioxide Equilibrium Scale). However, the external SD of Δ47 in sessions measuring ETH‐4 with resins is higher than in sessions without deliberate resin addition for the same measuring period.ConclusionsWe find that the potential contamination from the resin addition leads to a larger variability for Δ47 values in sessions measuring ETH‐4 including resins. We therefore recommend purification of embedded samples using a contamination trap with Porapak prior to analysis, if possible, or avoiding resins during sample preparation and workup, as well as monitoring the measurement quality during and after sessions with samples containing embedding resins.
Determination of rosmarinic acid and its N‐substituted analog A1 in rat plasma using high‐performance liquid chromatography–tandem mass spectrometry and its application in pharmacokinetics
Authors: Fu Shujie , Zhang Qinglang , Zhang Shiyu , Jiang Weizhe , Jiang Minjie 
Published: July 2023

AbstractBackgroundThe aim of this study was to determine the concentration of rosmarinic acid (RA) and its analog (E)‐3‐(3,4‐dihydroxyphenyl)‐2‐(3‐(3,4‐dihydroxyphenyl)acrylamido)propanoic acid (A1) in rat plasma following oral administration. The significance of this study lies in the development of a rapid, sensitive, and alternative method using liquid chromatography‐tandem mass spectrometry for the accurate quantification and identification of RA and A1 in vivo.MethodsLiquid chromatography‐tandem mass spectrometry was employed to analyze RA and A1 in rat plasma. A C18 column (1.9 µm, 2.1 × 100 mm) with a C18 guard column (5 µm, 2.1 × 10 mm) and a triple‐quadrupole mass spectrometer combined with an electrospray ionization source were utilized. Sample pretreatment involved a one‐step protein precipitation using isopropanol:ethyl acetate (20:80, v/v) as the solvent. Pseudoephedrine hydrochloride served as a standard.ResultsThe developed method exhibited a linear relationship within the concentration ranges of 5‐750 ng/ml for both RA and A1. Relative standard deviations in daily courses were less than 15%, and the relative errors recorded were within 15%. This is the first study to concentrate on determining A1 and RA in rat plasma through oral administration.ConclusionsThe liquid chromatography‐tandem mass spectrometry method developed in this study offers a rapid, sensitive, and alternative approach for the accurate quantification and identification of RA and A1 in vivo. The findings serve as a significant foundation for evaluating the clinical applications of the medicine.
Switching tube model predictive based controller design for multi‐agent unmanned aerial vehicle system with hybrid topology
Authors: Nejabat Erfan , Nikoofard Amirhossein 
Published: July 2023

AbstractThe decentralized control is provided for the multi‐agent unmanned aerial vehicle system and is designed based on leader‐follower configuration by graph theory. Next, primary model predictive control (MPC) is proposed in order to steer the error signal to the origin and specifically, an optimization algorithm is considered for the primary MPC controller in which the Newton optimization with back‐stepping step size definition is proposed for this manner. A robust modification is investigated for the system based on tube definition and considered to overcome the high‐frequency noise and external disturbances in a bound of 20% of the system output. The high‐frequency noises are designed outside of the primary controller band‐width. The hybrid controller is proposed for the system. The closed‐loop swarm system's control architecture, switches between the primary MPC controller to tube‐MPC controller in the presence of high‐frequency noises and external disturbances. The hybrid controller provides a more energy‐efficient outcome compared to the single mode controller. The final results provides a 7% faster simulation time. Afterward, the flexible formation theory is generalized for system. The possibility of changing leader is investigated in flexible formation and a scenario of switching leader is proposed for the system. The result of tracking for the controller is compared to proportional‐integral‐derivative and the problem of four agents in a flight scenario illustrates the issues and the comparison between the robust controller and the switching Tube‐MPC controller is provided. The results provide that the novel control architecture has a 47.6% lower rise time and 30.8% lower overshoot.
Rational Modulation of Single Atom Coordination Microenvironments in a BCN Monolayer for Multifunctional Electrocatalysis
Authors: He Tianwei , Kong Youchao , Zhou Tong , Zhang Jin , Santiago Alain R. Puente , Du Aijun , Luque Rafael , Liu Qingju 
Published: July 2023

AbstractSingle‐atom (SA) catalysts (SACs) have demonstrated outstanding catalytic performances toward plenty of relevant electrochemical reactions. Nevertheless, controlling the coordination microenvironment of catalytically active SAs to further enhance their catalytic oerformences has remained elusive up to now. Herein, a systematic investigation of 20 transition metal atoms that are coordinated with 20 different microenvironments in a boroncarbon‐nitride monolayer (BCN) is conducted using high‐throughput density functional theory calculations. The experimentally synthesized ternary BCN monolayer contains carbon, nitrogen, and boron atoms in its 2D network, thus providing a lot of new coordination environments than those of the current CxNy nanoplatforms. By exploring the structural/electrochemical stability, catalytic activity, selectivity, and electronic properties of 400 (20 × 20) TM‐BCN moieties, it is discovered that specific SA coordination environments can achieve superior stability and selectivity for different electrocatalytic reactions. Moreover, a universal descriptor to accelerate the experimental process toward the synthesis of BCN‐SACs is reported. These findings not only provide useful guidance for the synthesis of efficient multifunctional BCN‐SACs but also will immediately benefit researchers by levering up their understanding of the mechanistic effects of SA coordination microenvironments on electrocatalytic reactions.
Mild Methane Electrochemical Oxidation Boosted via Plasma Pre‐Activation
Authors: Sun Xiaogang , Wang Pengtang , Davey Kenneth , Zheng Yao , Qiao Shi‐Zhang 
Published: July 2023

AbstractObtaining partial methane oxidation reaction (MOR) with various oxygenates via a mild electrochemical method is practically difficult because of activation of stable C─H bond and consequent reaction pathway regulation. Here, a real‐time tandem MOR with cascaded plasma and electrocatalysis to activate and convert the methane (CH4) synergistically is reported for the first time. Boosted CH4 conversion is demonstrated toward value‐added products including, alcohols, carboxylates, and ketone via use of commercial Pd‐based electrocatalysts. Compared with hash industrial processes, a mild condition, that is, anode potential < 1.0 V versus RHE (reversible hydrogen electrode) is used that mitigates overoxidation of oxygenates and obviates competing reaction(s). One evidence that Pd(II) sites and surface adsorbed hydroxyls are important in facilitating activated‐CH4 species conversion, and establish a reaction mechanism for conversion(s) that involves coupling reactions between adsorbed hydroxyls, carbon monoxide and C1/C2 alkyls. One conclude that pre‐activation is important in boosting electrochemical partial MOR under mild conditions and will be of benefit in the development of sustainable CH4 conversion technology.
Axial Chlorine Induced Electron Delocalization in Atomically Dispersed FeN4 Electrocatalyst for Oxygen Reduction Reaction with Improved Hydrogen Peroxide Tolerance
Authors: Sabhapathy Palani , Raghunath Puttikam , Sabbah Amr , Shown Indrajit , Bayikadi Khasim Saheb , Xie Rui‐Kun , Krishnamoorthy Vimal , Lin Ming‐Chang , Chen Kuei‐Hsien , Chen Li‐Chyong 
Published: July 2023

AbstractAtomically dispersed iron sites on nitrogen‐doped carbon (Fe‐NC) are the most active Pt‐group‐metal‐free catalysts for oxygen reduction reaction (ORR). However, due to oxidative corrosion and the Fenton reaction, Fe‐NC catalysts are insufficiently active and stable. Herein, w e demonstrated that the axial Cl‐modified Fe‐NC (Cl‐Fe‐NC) electrocatalyst is active and stable for the ORR in acidic conditions with high H2O2 tolerance. The Cl‐Fe‐NC exhibits excellent ORR activity, with a high half‐wave potential (E1/2) of 0.82 V versus a reversible hydrogen electrode (RHE), comparable to Pt/C (E1/2 = 0.85 V versus RHE) and better than Fe‐NC (E1/2 = 0.79 V versus RHE). X‐ray absorption spectroscopy analysis confirms that chlorine is axially integrated into the FeN4. More interestingly, compared to Fe‐NC, the Fenton reaction is markedly suppressed in Cl‐Fe‐NC. In situ electrochemical impedance spectroscopy reveals that Cl‐Fe‐NC provides efficient electron transfer and faster reaction kinetics than Fe‐NC. Density functional theory calculations reveal that incorporating Cl into FeN4 can drive the electron density delocalization of the FeN4 site, leading to a moderate adsorption free energy of OH* (∆GOH*), d‐band center, and a high onset potential, and promotes the direct four‐electron‐transfer ORR with weak H2O2 binding ability compared to Cl‐free FeN4, indicating superior intrinsic ORR activity.
A Cross‐Plane Design for Wearable Thermoelectric Generators with High Stretchability and Output Performance
Authors: Yang Jing , Pu Yi , Yu Hui , Ye Dong‐dong , Liu Xi , Xin John H. 
Published: July 2023

AbstractStretchable wearable thermoelectric (TE) generators (WTEGs) without compromising output performance for real wearables have attracted much attention recently. Herein, a 3D thermoelectric generator with biaxial stretchability is constructed on the device level. Ultraflexible inorganic Ag/Ag2Se strips are sewn into the soft purl‐knit fabric, in which the thermoelectric legs are aligned in the direction of vertical heat flux. A stable and sufficient temperature gradient of 5.2 °C across the WTEG is therefore achieved when contacted with the wrist at a room temperature of 26.3 °C. The prepared TEG generates a high power density of 10.02 W m−2 at a vertical temperature gradient of 40 K. Meanwhile, the reliable energy harvesting promises a variation of less than 10% under the biaxial stretching up to 70% strain via leveraging the combined effects of the stretchability of knit fabric and geometry of TE strips. The knit fabric‐supported TEG enables a seamless conformation to the skin as well as efficient body heat harvesting, which can provide sustainable energy to low power consumption wearable electronics.
A robust and secure user authentication scheme based on multifactor and multi‐gateway in IoT enabled sensor networks
Authors: Kumar Ravi , Singh Samayveer , Singh Deepti , Kumar Mohit , Gill Sukhpal Singh 
Published: July 2023

AbstractThe Internet of Things (IoT) enabled wireless sensor networks (WSNs) are used to collect data from various nodes in hostile environments, but it is essential to authenticate legitimate nodes to prevent malicious attacks. Traditional authentication schemes may be vulnerable to attack, necessitating the development of more secure authentication techniques. To address this problem, we propose a novel authentication technique for multi‐gateway IoT‐enabled WSNs that achieves effective and secure data communication. The proposed scheme is based on biological information, hash, and XOR operations, which reduce computational costs. Passwords, biometric information, and session keys are updated securely to maintain forward and backward secrecy during communication. We provide an informal security analysis of the proposed scheme and a formal security analysis of the session key using the real‐or‐random (ROR) model. We also use the AVISPA simulation toolkit to verify the proposed user authentication scheme. Experimental results demonstrate that our proposed scheme is more effective than previous multi‐factor multi‐gateway authentication protocols.
Confinement effect of two‐way beam‐and‐slab system on the effective compressive strength of interior concrete columns
Authors: Prado Fabio Selleio , Meneghetti Leila Cristina , Stucchi Fernando Rebouças 
Published: July 2023

AbstractMultistory concrete buildings may resort to the strategy to cast columns and slabs with high and normal compressive concrete strength, respectively. Current design codes propose expressions to specify the effective compressive strength of interior columns confined only by flat slabs or beams with the same width as the column. However, when thin slabs and narrower beams are used, the confinement may not be enough to increase the lateral stress. The structural behavior of these interior columns is investigated in this paper using numerical nonlinear models. The influence of concrete strength column‐slab ratio, the steel reinforcement ratio of the column and the beam, beam height and the column width ratio and the biggest dimension of the column's cross section were tested with and without vertical load on the beam. The results were compared with expressions found in the literature.
Cyber oriented digital engineering
Authors: Mitola Joseph , Prys Mark 
Published: July 2023

AbstractThe purpose of cyber oriented digital engineering (CODE) is to provide a repeatable systems‐engineering process for systems to resist Stuxnet‐class advanced persistent threat (APT) cyberattacks. CODE integrates cyber thinking with systems thinking. CODE accomplishes this by extending the US Department of Defense (DoD) digital engineering (DE) framework with functional mission analysis for cyber (FMA‐C), hybrid cloud architecture, zero trust (ZT) principles, threat analysis, and hardware cyber hardening (HCH). The lack of success of red team attacks conducted in our laboratory against an exemplar system demonstrates how following the CODE systems engineering process actually does “bake cybersecurity into the system”, making the resulting systems architecture and implementations more resilient. In a recent Pilot Project, CODE enhanced the systems requirements document of the top left side of the systems engineering Vee. CODE Pilot requirements embodied ZT principles, including machine to machine (M2M) credential exchanges and internal self‐checking. We anticipate working with International Council on Systems Engineering (INCOSE), the object management group (OMG,) and others towards standardizing CODE's cyber‐systems engineering processes for broader use of the global systems engineering community.
Neo‐Nationalist Discourses and Teacher Identity Tensions in a Telecollaboration for Teachers of Minoritized Language Learners in Türkiye
Authors: Yazan Bedrettin , Turnbull John , Uzum Baburhan , Akayoglu Sedat 
Published: July 2023

ABSTRACTIn this paper, we focus on the situatedness of teacher identity and agency within sociopolitical contexts dominated by neo‐nationalist discourses and rely on data from online conversations among preservice and in‐service teachers of English in Türkiye and the United States (US). We report on data constructed in a telecollaboration (a.k.a., virtual intercultural exchange) that we, four TESOL teacher educators, designed for teachers to discuss issues of social justice (particularly for minoritized immigrant students) and to have a discursive and experiential space in which to negotiate their language teacher identities (LTI). Gathering 117 teachers from five universities (three in Türkiye, two in the US) and underserved school districts in both contexts, this telecollaboration is our pedagogical, agentive response to dominant neo‐nationalist discourses in the two countries. To make quantities of data more manageable, we analyze interactions from one‐third of those 117 participants (five of 15 small groups) to address this research question: How do preservice and in‐service teachers from Türkiye construct their teacher identities in response to neo‐nationalist discourses in their sociopolitical context? In particular, how do they engage in this identity work through asynchronous small‐group discussions in a social justice‐focused telecollaboration with teachers from the US? Findings indicate that participants from Türkiye discussed teacher agency, conservatism and cultural difference in the society, and discrimination/xenophobia against refugees as important factors that shape their work with minoritized English language learners. They experienced tensions in their identity construction between their desire to advocate for their students and the external forces coming from meso‐ and macro‐level policies that impact their instruction and assessment procedures. We discuss our findings in relation to previous research on language teacher identity and social justice in sociopolitical contexts shaped by neo‐nationalist discourses. We also share the implications of our study for pedagogizing identity in teacher education.
“This is our country, too”: Embodied Experiences of and Resistance to Neo‐nationalism in a Midwest School District
Authors: Stephens Crissa 
Published: July 2023

AbstractNationalist rhetoric is not new to the US political context of transnational migration (Johnson et al., 2018). However, the election cycle of 2016 amplified nationalist rhetoric and policy in new public spaces, including schools and classrooms. In this article, I analyze neo‐nationalist discourse as voiced by the Trump Administration in and adjacent to language classrooms and general education classrooms in a predominantly White, Midwestern school district with growing demographics of students designated as English Language Learners (ELLs). Using intertextual and interdiscursive analysis (Fairclough, 1992) and embodied sociolinguistics (Bucholtz & Hall, 2016), I trace how neo‐nationalist discourses entered the classrooms, homes, and, I argue, bodies of newly arrived, racialized, documented, and undocumented immigrant students. I demonstrate how such rhetoric and policy provoked physical manifestations of trauma coupled with resistance, showing how the circulation of neo‐nationalist ideas contributed to ideological constructions of immigrant student and family identities along lines of race, immigration status, and language. Based on my findings, I center participants' lived knowledge and goals to argue that these moments demand response in schools and language education classrooms and offer implications for research, policy, and practice.
Molecular imaging of pancreatic ductal adenocarcinoma
Authors: Huang Wei , Huang Gang , An Shuxian , Liu Jianjun 
Published: July 2023

AbstractPancreatic ductal adenocarcinoma (PDAC), a deadly cancer characterized by multiple molecular alterations, remains the most lethal cancer, with a 5‐year survival rate of about 3–15%. Early diagnosis and treatment monitoring are essential to improve patient survival. Traditional imaging methods can only provide structural information, but not biological processes. Nuclear medicine imaging combines the high sensitivity of radionuclides with high‐resolution structural imaging to visualize specific targets of PDAC for more accurate and reliable diagnosis and monitoring of therapeutic responses. In this review, we summarize the available literature regarding molecular nuclear medicine imaging in PDAC. We classify the probe targets into two categories, targeting tumor cell membranous and the tumor microenvironment, respectively. We summarize the latest evidence in this field and outline how these emerging strategies could potentially optimize clinical practice.
Petrogenesis of the Mesoarchaean Stella layered intrusion, South Africa: implications for the origin of PGE reefs in the upper portion of layered intrusions
Authors: Maier Wolfgang D , Barnes Sarah-Jane , Smith William D 
Published: July 2023

AbstractThe ~3033 Ma Stella layered intrusion is hosted by supracrustal rocks of the Kraaipan–Madibe greenstone terrane, South Africa. The studied portion of the intrusion consists mainly of magnetite leucogabbro and magnetite anorthosite, as well as several massive magnetite layers. The intrusion hosts a laterally continuous, ~60-m-thick, PGE mineralized interval, with total resources amounting to 108t Pt + Pd + Au, constituting one of the oldest known PGE reef-style mineralizations on Earth. The richest reef, with a grade of 4.4 ppm Pt+Pd over a width of 5–8 m, occurs in semi-massive magnetitite. It is suggested that the mineralized oxide and silicate layers formed through a combination of primary magmatic, late magmatic, and hydrothermal processes, including granular flow and phase sorting of a magnetite- and sulfide-bearing gabbroic crystal mush that crystallized from a tholeiitic basalt, as well as remobilization of S and metals by late magmatic and hydrothermal fluids that led to crystallization of platinum-group minerals.