bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection and Control of the Effective Magnetic Field in a Ca‐Doped Bi2Se3 Topological Insulator
Authors: Park Youn Ho , Kim Sung Jong , Park Tae‐Eon , Kim Kyoung‐Whan , Hruban Andrzej , Materna Andrzej , Strzelecka Stanislawa G. , Min Byoung‐Chul , Kim Hyung‐jun , Koo Hyun Cheol 
Published: February 2022

AbstractTopological insulators with surface states are expected to possess perfect spin polarization. Despite the strong potential for spintronic devices, the exact value and gate tuning of spin polarization in topological insulators have not yet been clearly demonstrated. In this research, Ca is doped into the well‐established topological material Bi2Se3 to enhance the spin‐orbit interaction and gate tunability. From the anisotropic magnetoresistance of the Ca‐doped Bi2Se3 channel, an effective magnetic field of ≈10 T is extracted. Also, the carrier types, i.e., p‐ and n‐channels, as well as the spin polarization are modulated by applying an external gate voltage. This work not only suggests a measurement platform to quantitatively estimate the spin characteristics of a topological insulator but also opens a path to realize gate‐controlled pure spin current.
On‐Chip Batteries for Dust‐Sized Computers
Authors: Li Yang , Zhu Minshen , Bandari Vineeth Kumar , Karnaushenko Dmitriy D. , Karnaushenko Daniil , Zhu Feng , Schmidt Oliver G. 
Published: February 2022

AbstractAdvances in microelectronics have enabled the use of miniaturized computers for autonomous intelligence at the size of a dust particle less than one square millimeter across and a few hundred micrometers thick, creating an environment for ubiquitous computing. However, the size mismatch between microbatteries and microelectronics has emerged as a fundamental barrier against the take‐off of tiny intelligent systems requiring power anytime anywhere. Mainstream microbattery structures include stacked thin films on the chip or electrode pillars and on‐chip interdigitated microelectrodes. Nevertheless, available technologies cannot shrink the footprint area of batteries while maintaining adequate energy storage. Alternatively, the on‐chip self‐assembly process known as micro‐origami is capable of winding stacked thin films into Swiss‐roll structures to reduce the footprint area, which exactly mimics the manufacture of the most successful full‐sized batteries—cylinder batteries. In addition to discussing in detail the technical difficulties of reducing the size of on‐chip microbatteries with various structures and potential solutions, this Perspective highlights the following two basic requirements for eventual integration in microcomputers: minimum energy density of 100 microwatt‐hour per square centimeter and monolithic integration with other functional electric circuits on the chip.
Efficient Ammonia Electrosynthesis and Energy Conversion through a Zn‐Nitrate Battery by Iron Doping Engineered Nickel Phosphide Catalyst
Authors: Zhang Rong , Guo Ying , Zhang Shaoce , Chen Dong , Zhao Yuwei , Huang Zhaodong , Ma Longtao , Li Pei , Yang Qi , Liang Guojin , Zhi Chunyi 
Published: February 2022

AbstractThe electrocatalytic nitrate reduction reaction (NO3‐RR) to ammonia (NH3) offers a promising alternative approach for NH3 production and nitrate‐based voltaic cells which can deliver both electricity and NH3 as products, are also highly attractive. However, nitrate‐to‐NH3 conversion involves a proton‐assisted multiple‐electron transfer process with considerable kinetic barrier, underlying the need for efficient catalysts for the NO3–RR. A Zn‐nitrate battery is reported to enable a “killing three birds with one stone” strategy for energy supply, ammonia production and removal of pollutants with the iron doped nickel phosphide (Fe/Ni2P) as a NO3–RR catalyst electrode. Iron doping induces a downshift of the d‐band center of Ni atoms to the Fermi level, allowing the optimization of Gibbs free energies for reaction intermediates. The Fe/Ni2P catalyst exhibits 94.3% NH3 Faradaic efficiency (FE) and nearly 100% nitrate conversion efficiency at –0.4 V vs. reversible hydrogen electrode (RHE). Further applying this highly efficient NO3–RR electrocatalyst as the cathode material, a novel Zn‐nitrate battery exhibits a power density of 3.25 mW cm–2 and a FE of 85.0% for NH3 production. This work enriches the application of Zn‐based batteries in the field of electrocatalysis and highlights the promise of bimetal phosphide for the NO3–RR.
Transitional organic forage systems in the southeastern U.S.: Production and nutritive value
Authors: Kubesch Jonathan O. C. , Nave Renata L. G. , Cui Song , Bates Gary E. , Butler David M. , Pantalone Vince 
Published: February 2022

AbstractLimited work has been done to develop organic forage programs in humid subtropical regions despite growing demand for high‐value forage and organic products. Alternative crops were compared for optimizing forage production and nutritive value under organic conditions in the southeastern United States. The study was conducted at the Middle Tennessee AgResearch and Education Center, in Spring Hill, Tennessee. Forage treatments consisted of (a) monoculture tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.], (b) monoculture bermudagrass [Cynodon dactlyon (L.) Pers.], (c) tall fescue and alfalfa (Medicago sativa L.) mixture, (d) bermudagrass and alfalfa mixture, and (e) an annual rotation of winter wheat (Triticum aestivum L.) mixed with winter pea (Pisum sativum L.) followed by sorghum–sudangrass [Sorghum bicolor (L.) Moench x S. sudanese (Piper) Stapf.] mixed with cowpea [Vigna unguiculata (L.) Walp.] mixture. Perennial treatments were established during the 2017–2018 growing season. Monthly production was measured in the 2018–2019 and 2019–2020 growing seasons. Botanical composition of forage mass fluctuated due to establishment dynamics and weed competition, affecting forage quantity and quality. The annual rotation was the highest‐yielding treatment, producing more than 6,000 kg−1, though each tall fescue and tall fescue–alfalfa treatments produced ∼4,000 kg ha−1. Nutritive value was sufficient for most livestock operations, with forage crude protein concentration averaging ∼150 g kg−1 across treatments and growing seasons. For transitioning organic producers, a perennial forage will likely favor long‐term sustainability, whereas the annual rotation may be useful during the transition period to reduce weed pressure before transitioning to a perennial forage system.
Reversibly Photoswitching Upconversion Nanoparticles for Super‐Sensitive Photoacoustic Molecular Imaging
Authors: Liu Cheng , Zheng Xianchuang , Dai Tingting , Wang Huiliang , Chen Xian , Chen Bing , Sun Tianying , Wang Feng , Chu Steven , Rao Jianghong 
Published: February 2022

AbstractPhotoacoustic (PA) imaging uses light excitation to generate the acoustic signal for detection and improves tissue penetration depth and spatial resolution in the clinically relevant depth of living subjects. However, strong background signals from blood and pigments have significantly compromised the sensitivity of PA imaging with exogenous contrast agents. Here we report a nanoparticle‐based probe design that uses light to reversibly modulate the PA emission to enable photoacoustic photoswitching imaging (PAPSI) in living mice. Such a nanoprobe is built with upconverting nanocrystals and photoswitchable small molecules and can be switched on by NIR light through upconversion to UV energy. Reversibly photoswitching of the nanoprobe reliably removed strong tissue background, increased the contrast‐to‐noise ratio, and thus improved imaging sensitivity. We have shown that PAPSI can image 0.05 nM of the nanoprobe in hemoglobin solutions and 104 labeled cancer cells after implantation in living mice using a commercial PA imager.
Carboxyl Methyltransferase Catalysed Formation of Mono‐ and Dimethyl Esters under Aqueous Conditions: Application in Cascade Biocatalysis
Authors: Ward Lucy C. , McCue Hannah V. , Rigden Daniel J. , Kershaw Neil M. , Ashbrook Chloe , Hatton Harry , Goulding Ellie , Johnson James R. , Carnell Andrew J. 
Published: February 2022

AbstractCarboxyl methyltransferase (CMT) enzymes catalyse the biomethylation of carboxylic acids under aqueous conditions and have potential for use in synthetic enzyme cascades. Herein we report that the enzyme FtpM from Aspergillus fumigatus can methylate a broad range of aromatic mono‐ and dicarboxylic acids in good to excellent conversions. The enzyme shows high regioselectivity on its natural substrate fumaryl‐l‐tyrosine, trans, trans‐muconic acid and a number of the dicarboxylic acids tested. Dicarboxylic acids are generally better substrates than monocarboxylic acids, although some substituents are able to compensate for the absence of a second acid group. For dicarboxylic acids, the second methylation shows strong pH dependency with an optimum at pH 5.5–6. Potential for application in industrial biotechnology was demonstrated in a cascade for the production of a bioplastics precursor (FDME) from bioderived 5‐hydroxymethylfurfural (HMF).
A new‐type terephthalonitrile derivative flame retardant of bi‐DOPO compound with hydroxyl and amino groups on epoxy resin
Authors: Guo Yong , Chen Zhongwei , Yu Yuan , Chen Tingting , Zhang Qingwu , Li Changxin , Jiang Juncheng 
Published: February 2022

AbstractA new‐type flame retardant DEZ of bi‐DOPO compound containing bi‐hydroxy and two amino groups, was synthesized from terephthalonitrile, hydroxylamine hydrochloride, and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide, and used with curing agent 4,4′‐diamino‐diphenylmethane to prepare flame retard epoxy resin (EP) composites. 1H and 31P nuclear magnetic resonance spectra and Fourier transform infrared spectra have determined the chemical structure of DEZ. The properties of cured EP composites were explicitly evaluated by differential scanning calorimeter, thermogravimetric analysis, the limiting oxygen index (LOI), vertical burning (UL‐94) test, cone calorimetry test, and flexural test. The 1 wt% addition of DEZ could improve the EP composites by almost 14.4% of flexural strength and 29.6% of flexural modulus, respectively. The LOI of EP composites with 5 wt% of DEZ was 29.7% and EP composites reached a V‐0 rating in the UL‐94 test, as well as total heat release was decreased by 11.2%. All EP modified by DEZ exhibited a blow‐out effect in the combustion process, which was due to the release of pyrolysis gases and incombustible gases containing phosphorus radicals and nitrogen compounds.
Morphological changes of polyamide 11 through the corrected inherent viscosity plateau
Authors: da Costa Danyelle R. , da Costa Marysilvia F. , Grytten Frode 
Published: February 2022

AbstractThe pressure barrier is one of the layers that compose flexible pipes used for oil and gas exploitation. It is made from a thermoplastic that must endure harsh operation conditions keeping its properties during the projected lifetime. Polyamide 11 is used when operating temperatures are below 80°C. Although polyamides' aging chemical mechanisms are well established in the literature, their mechanical behavior is defined by deformation processes that, in turn, depend on the polymer molecular structure. The dominant aging mechanism, hydrolysis, has been used by industry as a parameter for lifetime evaluation. Different morphological arrangements may occur following chain scission depending on the operating environment, leading to line failure or unnecessary substitution. The complex combination of parameters affects the aging processes, chain scission, morphological changes, and, consequently, mechanical behavior. Understanding the role of environmental parameters such as pH, acidic content, among others, is crucial to improving the model used. In this context, this work evaluates the aging of PA11 in two fluids with different acid concentrations but the same pH. The goal is to assess the impact of the amount of acid molecules on the polymer structure at 120°C and quantify the aging of PA11 using acceptance criteria methods.
Small monsters: Insect predation limits reproduction of yellow‐bellied toad Bombina variegata to ponds in their earliest successional stage
Authors: Łaciak Małgorzata , Zając Tadeusz , Adamski Paweł , Bielański Wojciech , Ćmiel Adam , Łaciak Tomasz , Lipińska Anna 
Published: February 2022

Abstract

The disappearance and deterioration of amphibian breeding habitats is a major cause of their global extinction. In Europe, this problem affects the yellow‐bellied toad Bombina variegata, which inhabits small ponds in the early stages of succession, where no predatory invertebrate species normally occur. Nonetheless, as habitats, small temporary ponds are highly endangered, a situation that is intensifying with urban spread.
A system of 13 pairs of artificial ponds was constructed in 2012 for the breeding of B. variegata with the aim of reconnecting disjunct populations. During the 2 years of the study, one of the twin ponds was regularly cleared of emergent vegetation and invertebrates. The survival rates of the tadpoles released in the cleared and uncleared ponds were analysed.
The survival rate of the tadpoles released into the cleared ponds was higher than of those introduced into the uncleared ones. Tadpole survival rates were also higher in new, single ponds, constructed in 2013.
The lower survival rates of the introduced tadpoles are best explained by the presence of predatory aquatic invertebrates, particularly the large diving beetle Dytiscus marginalis. Experimentally obtained consumption rates indicate that one Dytiscus larva is capable of destroying a typical clutch of B. variegata tadpoles within a few hours, much faster than any of the other insect predators tested.
The impact of freshwater invertebrates on tadpoles is frequently studied but rarely quantified. For conservation measures to be effective, quantitative standards need to be applied that describe the impact of predation in a predictable manner.
Construction of artificial small ponds is broadly accepted as an important conservation measure compensating for the disappearance of natural amphibian breeding sites. This function of artificial ponds may be substantially enhanced by the periodic removal of invertebrate predators.
First occurrence ofPsammophis(Serpentes) from Europe witnesses another Messinian herpetofaunal dispersal from Africa – biogeographic implications and a discussion of the vertebral morphology of psammophiid snakes
Authors: Georgalis Georgios L. , Szyndlar Zbigniew 
Published: February 2022

AbstractWe here describe abundant new snake material from the late Miocene (MN 13) of Salobreña, Spain. Vertebral morphology suggests a referral of the specimens to the extant psammophiidPsammophis, documenting the first occurrence of this genus in Europe. The diversity and disparity across the vertebral morphology of different psammophiid genera are discussed. We identify vertebral features that could diagnosePsammophisand therefore enable the recognition of the genus in the fossil record. A comparison of the new Spanish form with other taxa is conducted. We provide a detailed review of the psammophiid fossil record. Material previously described from the middle Miocene of Beni Mellal, Morocco is here tentatively referred to as ?Psammophissp., an action that renders that occurrence as the oldest (probable) record of the genus and Psammophiidae as a whole, providing thus a potential calibration point. On the other hand, Eastern European Pliocene material that had been previously supposedly referred toPsammophisis here discarded as being rather fragmentary, not affording any more precise determination. The two psammophiid generaPsammophisandMalpolonappear almost simultaneously in the European fossil record (MN 13), with the former achieving only a short‐lived and apparently geographically limited distribution in the continent, while the latter still exists in its modern herpetofauna. We assess biogeographic implications of the new find, suggesting a direct dispersal event from northwestern Africa to the Iberian Peninsula during the late Miocene, facilitated by the Messinian Salinity Crisis.
Heteroleptic Tripalladium(II) Cages
Authors: Findlay James A. , Patil Komal M. , Gardiner Michael G. , MacDermott‐Opeskin Hugo I. , O'Mara Megan L. , Kruger Paul E. , Preston Dan 
Published: February 2022

AbstractThere is a concerted attempt to develop self‐assembled metallo‐cages of greater structural complexity, and heteroleptic PdII cages are emerging as prime candidates in these efforts. Most of these are dinuclear: few examples of higher nuclearity have been reported. We demonstrate here a robust method for the formation of tripalladium(II) cages from the 2 : 3 : 3 combination of a tritopic ligand, PdII, and a selection of ditopic ligands of the correct size and geometry.
Towards a collaboration framework for circular economy: The role of dynamic capabilities and open innovation
Authors: Köhler Julia , Sönnichsen Sönnich Dahl , Beske‐Jansen Philip 
Published: February 2022

AbstractTransitioning from linear to circular production systems requires interactions that include cross‐sectoral collaboration in networks. Understanding the role of collaboration within these networks can support the transition to a circular economy. To understand cross‐sectoral collaborative endeavors, this paper develops a collaboration framework for circular economy by combining and interlinking three theories: the relational view, open innovation, and dynamic capabilities. The framework is applied to the Circle‐House‐Project, a cross‐sectoral collaborative project aimed at scaling circular economy in the Danish construction sector. The explorative data included desk research and 15 semistructured interviews with expert project partners. The findings were transcribed, structured, coded, condensed, and categorized to provide an illustrative case based on a lighthouse project in the construction sector, affording a novel understanding of how cross‐sectoral collaboration can support advancing circular economy practices by developing knowledge‐sharing routines and ecocentric dynamic capabilities. The paper provides insights for academics and practitioners from a broad field by combining diverse interdisciplinary perspectives to unlock the potential of cross‐sectoral collaboration for advancing circular economy.
How engineering instructors supported students during emergency remote instruction: A case comparison
Authors: Douglas Kerrie A. , Johnston Amanda C. , Martin Julie P. , Short Taylor , Soto‐Pérez Rene A. 
Published: February 2022

AbstractThe rapid move to emergency remote teaching (ERT) during spring 2020 revealed many challenges for instructors, especially for the team and project‐based courses that previously relied on informal, in‐person interactions and laboratory equipment. The purpose of this case comparison study is to learn from this transition to identify ways that instructors can support the success of students in online, project‐based courses during times of crisis. We use data from student surveys, student and instructor interviews, and course documents to examine ways that student–student and student–instructor relationships changed during the move to ERT and how instructor decisions affected these relationships. We frame our work with social capital theory and social constructivism, specifically the community of inquiry framework. We examine two case studies: a first‐year engineering course and a junior‐/senior‐level engineering technology capstone course, both with large class sizes at a large research university. In both cases, students indicated that the shift to online learning decreased their access to relationships and supports from people who influenced their success and persistence. Although the instructors approached the transition differently, the data and analysis support recommendations for future moves to ERT in project‐based design courses. Recommendations include: Establishing mechanisms for informal conversations between students and between students and instructors; establishing a weekly routine that includes some level of real‐time, verbal communication; instructors being available for just‐in‐time feedback and questions as they arise; and establish a backup plan for ERT learning objectives, should the physical facilities no longer be accessible.
Practitioner responses to children and young people involved in forced marriage
Authors: Tarr Sukey , Gupta Anna 
Published: February 2022

AbstractForced marriage is recognised as a form of child abuse in the UK. Despite evidence that this is a growing problem, there is little current research concerning the responses of child protection practitioners. This article is based on a study that explored the views and experiences of a range of practitioners who had been involved with safeguarding children with respect to forced marriage. Ten semi‐structured interviews were carried out, followed by two focus groups (n = 13); these explored the challenges and best practice related to working with children at risk of or in forced marriage situations. The findings highlighted the complex nature of the work and the particular vulnerability of children affected by forced marriage. The study found that practitioners struggled to respond effectively when guidance was unclear or when they had limited knowledge and experience of forced marriage. Effective practice was associated with a high standard of interagency work locally and with practitioners who had confidence and experience and were able to work proactively and assertively.Key Practitioner Messages

Effective practice responses to forced marriage require clearer national and local policy and guidance.
Knowledgeable, confident and proactive staff enable good‐quality risk assessments and service responses.
Practitioner training and development should include enhancing cultural competence and confidence when working with marginalised/BME families.
Forced marriage is a nuanced, complex and diverse issue affected by high levels of vulnerability in children and young people.
Transition Metal Catalyst Free Synthesis of Olefins from Organoboron Derivatives**
Authors: Bojaryn K. , Hirschhäuser C. 
Published: February 2022

AbstractStereoselective preparation of highly substituted olefins is still a severe challenge that requires well defined elimination precursors. Organoboron chemistry is particularly suited for the preparation of molecules with adjacent stereocenters. As organo boron substrates with leaving groups in β‐position can undergo stereospecificsyn‐ oranti‐elimination, this chemistry harbors great potential for the synthesis of complex olefins. In recent years three main strategies emerged, which differ in their approach to the β‐functionalized organoboron elimination precursor. (i) Stereoselective preparation of such elimination precursor can be achieved by addition of a boron‐stabilized anion (d1) to an aldehyde or ketone (a1) or diastereoselective 1,3‐rearrangement of suitable boron‐ate‐complexes. Stereospecific methods rely either on (ii) diastereospecific 1,2‐metalate rearrangement of boron‐ate‐complexes that involve opening of appropriate heterocycles or (iii) addition of chiral carbenoids (d1*) to chiral boronates (a1*) with a leaving group in α‐position.