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The use of nondestructive sensing technologies is critical in the evaluation of concrete conditions and structural integrity. In our previous experimental studies, we showed the use of the ground-penetrating radar (GPR)-based nondestructive evaluation method to examine low-range concrete subsurface boundary conditions. As the characterization of GPR signals based on multiple factors is crucial for furthering the accurate conditions of concrete subsurfaces, we investigate the GPR signals in this letter by simulating electromagnetic wave propagation on concrete models through the use of the finite-difference time-domain method. The effects of concrete relative permittivity, the standoff distance of GPR from the top surface of concrete, the operating frequency of GPR, and the depth height of multilayered concrete on the GPR measurements were all investigated, and conclusions were established. Through the outcomes of this investigation, we will be able to choose the most appropriate operating frequency for the GPR for collecting measurements on concrete infrastructures at the most effective standoff distance to the surface and subsurface depths under a variety of relative permittivity conditions in various locations.

Feminism has come a long way. Gone are the days when women took out rallies to fight for their suffragist rights. Gone are the days when women demanded for the demonstration of equality in their pay slips. Gone are the days when women writers were bashful to reveal their gender identify and wrote in the guise of a male. Thanks to the surging waves of Feminists movements, the emergence of the "new woman" has turned the tables on the patriarchal world order. In an age of cyber punkism, when the proxemics of the 'private' and the 'public' has been problematised, the 'muscle power' has been contested and wrested by the 'lung power' and 'scribal power' of women's writing and has become a force to reckon with The claims, however, of feminism in its fight for women's liberation are not without limitations. Black feminists Barbara Christian and Alice Walker and Third world feminists Gayatri Chakravarthi Spivak and Chandra Talpade Mohanfy have articulated their concerns of homogenizing the female subjectivity without contextualizing its cultural constructions. This paper seeks to extend the argument further by looking into the representational politics within the Third World feminist discourses. Also the lingo, 'women's liberation' has become the watchword of feminist's movements across worlds (First, Second, and the Third). Drawing on Jacques Lacan's theoretical insistence that there is no feminine outside language, the ambiguity that clouds the term/language of feminists is subjected to scrutiny all the while highlighting the need for a comprehensive sociological awareness in articulating women's concerns. Therefore this paper purports to interrogate the validation of certain claims of 'feminism' and its complicity with the Lichtung of academia which is increasingly becoming a fetish.

The Square Kilometre Array telescopes have recently started their construction phase, after years of pre-construction effort. The new SKA Observatory (SKAO) intergovernmental organisation has been created, and the start of construction ($\mathrm{T_0}$) has already happened. In this talk, we summarise the construction progress of our facility, and the role that agile software development and open-source collaboration, and in particular the development of our TANGO-based control system, is playing., Comment: 7 pages, 4 figures, presented at ICALEPCS21, Shanghai, China, 2021, paper MOAL03

A novel PtIV triazolato azido complex [3]-[N1,N3] has been synthesised via a strain-promoted double-click reaction (SPDC) between a PtIV azido complex (1) and the Sondheimer diyne (2). Photoactivation of [3]-[N1,N3] with visible light (452 nm) in the presence of 5'-guanosine monophosphate (5'-GMP) produced both PtIV and PtII 5'-GMP species; EPR spectroscopy confirmed the production of both azidyl and hydroxyl radicals. Spin-trapping of photogenerated radicals - particularly hydroxyl radicals - was significantly reduced in the presence of 5'-GMP.

A novel PtIV azido triazolato complex exists as an equilibrium between two species in d3-MeCN and evolves azide radicals (but not hydroxide radicals) when irradiated with visible light., The platinum(iv) azido complex trans,trans,trans-[PtIV(N3)2(OH)2(py)2] (1) undergoes cycloaddition with 1,4-diphenyl-2-butyne-1,4-dione (2) under mild, catalyst-free conditions, affording a number of mono and bis click products. The major mono click product (3) exists in MeCN as an equilibrium mixture between two species; 3a and 3b rapidly interconvert through nucleophilic attack of the axial Pt–OH group at the adjacent Ph–CO group. The kinetic and thermodynamic parameters for this interconversion have been measured by selective saturation-transfer NMR spectroscopic experiments and are consistent with cyclisation at the Pt centre. Complex 3b was also characterised by X-ray crystallography. Visible light irradiation (440–480 nm) of 3 in d3-MeCN produces azidyl radicals (N3˙), as demonstrated by EPR spin-trapping with DMPO; no generation of hydroxyl radicals was observed. 1H–195Pt HMBC NMR confirmed that the photoproducts were PtIV rather than PtII species, and HPLC was consistent with these being [3–N3]+ species; no facile photoejection of the triazolato ligand was observed, consistent with MS/MS fragmentation of 3. When 3 was irradiated in the presence of 5′-GMP, no 5′-GMP photoproducts were observed, suggesting that complex 3 is likely to exhibit significantly simplified biological activity (release of azidyl radicals but not DNA binding) compared with complex 1.

Introduction Use of the prehospital 12-lead ECG (PHECG) is recommended in patients presenting to emergency medical services (EMS) with suspected acute coronary syndrome (ACS). Prior research found that although PHECG use was associated with improved 30-day survival, a third of patients (typically women, the elderly and those with comorbidities) under EMS care did not receive a PHECG. The overall aim of the PHECG2 study is to update evidence on care and outcomes for patients eligible for PHECG, specifically addressing the following research questions: (1) Is there a difference in 30-day mortality, and in reperfusion rate, between those who do and those who do not receive PHECG? (2) Has the proportion of eligible patients who receive PHECG changed since the introduction of primary percutaneous coronary intervention networks? (3) Are patients that receive PHECG different from those that do not in terms of social and demographic factors, or prehospital clinical presentation? (4) What factors influence EMS clinicians' decisions to perform PHECG? Methods and analysis This is an explanatory, mixed-method study comprising four work packages (WPs). WP1 is a population-based, linked-data analysis of a national ACS registry (Myocardial Ischaemia National Audit Project). WP2 is a retrospective chart review of patient records from three large regional EMS. WP3 comprises focus groups of EMS personnel. WP4 will synthesise findings from WP1-3 to inform the development of an intervention to increase PHECG uptake. Ethics and dissemination The study has been approved by the London-Hampstead Research Ethics Committee (ref: 18LO1679). Findings will be disseminated through feedback to participating EMS, conference presentations and publication in peer-reviewed journals.

With the increased brilliance of state-of-the-art Synchrotron radiation sources and the advent of Free Electron Lasers enabling revolutionary science with EUV to X-ray photons comes an urgent need for suitable photon imaging detectors. Requirements include high frame rates, very large dynamic range, single-photon counting capability with low probability of false positives, and (multi)-megapixels

The oxidative dimerisation reaction of N,N-dimethyl-p-toluidine (DMT) in acetonitrile was studied by cyclic voltammetry using a range of concentrations from 1 to 70 mM at microdisk electrodes of radii 10, 12.5, and 50 μm using scan rates from 20 mV s-1 to 6 V s-1. Theory was developed to simulate the following mechanism using the ADI method and comparison made to experimental voltammograms.The mechanism was found to be consistent with the observed data under all experimental conditions employed. The following rate constants were inferred: k1=(5.9±2.2)×105 cm3 mol-1 s-1, k-1≈0, and k2=(9.2±3.8)×108 cm3 mol-1 s-1. © 2002 Elsevier Science B.V. All rights reserved.

CYP238A1, one of the two P450 enzymes in the genome of Pseudomonas putida KT2440, has been produced heterologously in Escherichia coli, purified, and found to bind acyclic and cyclic terpene alcohols such as farnesol, nerolidol, linalool, and terpineol. The other P450 enzyme in this organism (gene locus: PP1950) was also produced in E. coli but no substrate has been identified from a limited screen. A phthalate family oxygenase reductase (PFOR) encoded by the PP1957 gene, just downstream of the PP1955 gene for CYP238A1, accepts electrons from the reduced form of both nicotinamide adenine dinucleotide (NADH) and nicotinamide adenine dinucleotide phosphate and is able to support monooxygenase activity of CYP238A1, both in vitro and in E. coli, in which both enzymes are produced. CYP238A1 oxidizes cis- and trans-nerolidol to the 9-hydroxy product, with no evidence of attack at the olefinic double bonds. The NADH turnover rate of 170 nmol(nmol-P450)⁻¹ Min⁻¹ for CYP238A1 with cis-nerolidol as substrate at a PP1957:CYP238A1 concentration ratio of 8:1 suggests that this PFOR could function as the physiological redox partner for CYP238A1. The physiological role of CYP238A1 may be related to the PP1955 gene being part of an island/cluster of inducible genes associated with energy metabolism and response to xenobiotics.

We report the synthesis, structural characterisation andsolution-phase dynamics of a series of polyaromatic hydrocarbon complexes of the 12-electron {Rh(PiBu 3) 2} + fragment. Crystal structures of this fragment with benzene, naphthalene, anthracene, pyrene, triphenylene and coronene are described, alongside their solution NMR spectroscopic data. The ligands map out a systematic increase in size of the aromatic subunit, and represent an approach to the limiting case of coordination to a graphene surface. The solid-state and solution structures of a {Rh(COD)} + fragment coordinated to a hexa-peri-hexabenzocoronene are also reported. A range of polyaromatic hydrocarbons of increasing size (naphthalene through coronene) have been prepared and their solid-state and solution structures investigated. Copyright © 2011 WILEY-VCH Verlag GmbH and Co. KGaA.

The electrochemical oxidation of N,N-diethyl-p-phenylenediamine in dimethylformamide has been studied at platinum and gold microdisk electrodes of various radii between 6.7 and 66 μm. The voltammetric responses revealed two electrochemically reversible waves the second of which becomes larger at higher concentrations and bigger electrode radii. The voltammetric signals have been modelled and the electrochemical oxidation reaction is not inconsistent with an ECrevECE reaction. Kinetic parameters are reported.

This report documents the scientific activities on board the Royal Research Ship (RRS) James Clark Ross (JCR) during the eighth Atlantic Meridional Transect (AMT-8), 24 April to 7 June 1999. There are three objectives of the AMT program. The first is to derive an improved understanding of the links between biogeochemical processes, biogenic gas exchange, air-sea interactions, and the effects on, and responses of, oceanic ecosystems and climate change. The second is to investigate the functional roles of biological particles and processes that influence ocean colour in ecosystems dynamics. The third is the algorithm development and validation of remotely sensed observations of ocean colour.

The binuclear allenyl complex [Fe2(CO)6(μ-PPh2){μ-η 1:η2α,β-(H)C α=Cβ=CγH2}] (1) has been prepared, and its reactivity with organolithium nucleophiles is described. Prop-2-yne bromide reacts with [Fe2(CO)7(μ-PPh2)]-Na +, via an SN2 mechanism, to give [Fe2(CO)6(μ-PPh2){μ-η1: η2α,β-(H)Cα=C β=CγH2}], the first example of a phosphido-bridged allenyl complex. The molecular structure of [Fe2(CO)6(μ-PPh2){μ-η 1:η2-(H)Cα=Cβ=C γH2}]: (1) was determined by single-crystal X-ray diffraction and shows that the allenyl ligand is coordinated through Cα-Cβ. Variable-temperature 1H and 13C NMR studies reveal a high-energy exchange process that equilibrates the diastereotopic allenyl protons, presumably via a zwitterionic intermediate, as well as two independent trigonal rotations that act to exchange the carbonyl ligands on each unique Fe(CO)3 group. Complex 1 reacts with organolithium reagents (RLi; R = Me, nBu, Ph, C4H3S), via allenyl-carbonyl-nucleophile coupling, to afford the binuclear β,γ-unsaturated ketones [Fe2(CO)5{P(OMe)3}(μ-PPh 2)(μ-η1:η2-{RC(O)CH 2}C=CH2)] (R = Me, 3a; nBu, 3b; Ph, 3c; C4H3S, 3d), and a single-crystal X-ray structure determination of 3a was undertaken to confirm the connectivity of the hydrocarbyl ligand. The most likely mechanism for the formation of 3a-d involves nucleophilic attack of R- at CO to give an acylate intermediate followed by migration of RCO to Cα of the allenyl and protonation of the resulting enolate to give the unstable alkenyl complexes [Fe2(CO)5(μ-PPh2)(μ-η 1(C):η1-(C):η2(C)-{RC(O)CH 2}C=CH2)] (R = Me, 2a; Bu, 2b; Ph, 2c; C4H3S, 2d). Finally, substitution of the metal-coordinated ester carbonyl in 2a-d with trimethylphosphite affords 3a-d as stable crystalline products.

The binuclear allenyl complex [Fe2(CO)6(μ-PPh2)-{μ-η1 : η2-(H)Cα=Cβ=C γH2}] 1 reacts with PPh2H and PPhH2 to afford [Fe2(CO)6(μ-PPh2){μ-η1 : η2-(Me)C=CH(PPh2)}] 2 and [{Fe2(CO)6(μ-PPh2)-(μ-η1 : η2-(Me)C=CH)}2PPh] 3 respectively both of which contain μ-η1 : η2-coordinated phosphino-substituted alkenyl ligands formed via an unprecedented regiospecific attack of phosphorus nucleophiles at Caα of the μ-η1 : η2-coordinated allenyl followed by a facile 1,4-hydrogen migration.

The PERCIVAL ("Pixelated Energy Resolving CMOS Imager, Versatile and Large") is a collaboration of DESY, RAL/STFC, ELETTRA, and DLS to develop a monolithic active pixel sensor (MAPS) to provide a suitable detector for photon science for the photon energy regime between 250 eV and 1 keV. An important performance parameter is the spatial resolution which can be inferred from the Modulation Transfer Function (MTF). The MTF measures in optical systems the relative contrast of a pattern in function of the spatial frequency. With a back-thinned and back-illuminated PERCIVAL prototype chip, dedicated MTF evaluation data were taken at Elettra's TwinMic Beamline in March 2014 at a photon energy of 535 eV. We will present our MTF derivation approaches together with MTF results for 3 pixel types of the irradiated test sensor.