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    Bioinspired Bi2O3-ZrO2 nanocomposite heterojunction as energy storage material and high-performance electrocatalyst for water oxidation

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    Phyto-mediated nanocomposite materials possess significant potential in morphological control as well as in electrocatalytic activity, which is the main reason for steered interest in the design of new materials for their applications in water splitting. In this work, nanocomposites of Bi2O3-ZrO2 have been prepared by using Amaranthus viridis L. (AVL)–based aqueous extract as a reducing agent. The synthesized nanomaterial’s composition and charge storage properties have been examined in detail. A crystalline structure for the synthesized Bi2O3-ZrO2-based nanocomposite has been elucidated by XRD analysis, while analysis through FTIR, UV, and SEM along with EDX also confirmed the successful biogenic synthesis of the desired nanocomposite. The synthesized biocomposite material is further applied on the nickel foam to be utilized in supercapacitor applications as a working electrode. Results manifest an exceptional specific capacitance value of 283.9 F/g at 2 mV/s by the AVL-Bi2O3-ZrO2 electrode. The columbic efficiency of the electrode was determined to be 99% even after 5000 GCD cycles. The synthesized Bi2O3-ZrO2 nanocomposite is considered to be an efficient electrocatalyst with a comparatively lower band gap of 2.7 eV. This lower bandgap further manifests its potential role in environmental remediation processes through photocatalysis. Additionally, the Bi2O3-ZrO2 composite has also been tested for cyclic stability through chronoamperometry showing reasonable stability. The Ragone plot has been used to determine the power density and energy density as 12 WhKg−1 and 3 KWKg−1 manifesting the higher capacitive behavior of nanocomposite. The synthesized bio-based nanocomposite has a good potential as an electrocatalyst for water splitting having highest productivity of the electrode up to 16.5 h as displayed by hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). To the best of our knowledge, this study represents the first account on the green synthesis of Bi2O3-ZrO2 nanocomposites, wherein Amaranthus viridis L. (AVL) serves as the eco-friendly source, in combination with Bi2O3, which has reduced toxicity, and ZrO2, renowned for its exceptional stability. Our investigation further highlights the importance of synthesis of materials through phytoextract-assisted route for utilization in overall water splitting and energy storage applications

    Search for heavy Higgs bosons with flavour-violating couplings in multi-lepton plus b-jets final states in pp collisions at 13 TeV with the ATLAS detector

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    Metrology for sub-THz Measurement of Dielectric and Chiral Matter

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    An advanced technique for waveguide sensing has been developed, designed, fabricated, and experimentally validated. It is based on the study of WR10 (75-110 GHz) rectangular waveguide with a non-radiating slot to place a microfluidic sample holder inside. This enables complex permittivity sensing of nanolitre (≈400 ) volumes of fluids. A microfluidic sample holder has been designed and simulated to assess how the pipe configuration, diameter, and depth inside the rectangular waveguide influence the ability to sense changes in complex permittivity. The key finding in the simulation was the ability to see distinct changes in the frequency shift of |11| resonance, and the transmission magnitude shift of |21| in response to varying ∗ of the sample under test (SUT). The changes to the pipe parameters show that the larger the volume of liquid inside the waveguide, these shifts become more amplified. The simulated design was then 3D printed and measured using a vector network analyser. The simulated model was then altered to better match the manufactured model. The measurements closely matched the simulations for the empty sample holder, and the isopropyl alcohol SUT, which had an error of 12.2% for ′ and 1.5% for ′′. However, for higher ′ and higher loss tangent SUT the simulations were unable to predict the measurements. This is attributed to the simulation model being unable to account for intricate details and imperfections in the manufactured model. Furthermore, a novel metrologically based methodology to characterise dielectric chiral matter has been proposed in the presented work. Fundamentally, it is based on a critical revisiting of existing methods using Jones’ matrices. Firstly, the methodology has been performed on a recent circular dichroism (CD) spectrometer design created in collaboration with Dr Jhih-Hong Cheng. It was deemed to have previously unappreciated drawbacks due to the Faraday rotation angle of the strontium hexaferrite plate (FP) component deviating significantly from the initially expected =45°. Therefore, two new, novel methods have been developed and experimentally validated. These utilise only wire grid polariser (WGP) elements, to extract the four Jones’ matrix components of the SUT. During the creation of these methods, it was assumed that the WGP were ideal components. This assumption was then removed and the viability of the two methods was assessed. Both methodologies were viable, however only the second of which was used for measurement due to the lack of the WGP necessary to do so. The WGP were characterised, and Jones’ matrix analysis with the characterised components was then performed, this enabled the inspection of the purity of the measurements. This analysis highlighted that the extracted Jones’ matrix components of the SUT will have impurities. These impurities will cause an achiral sample to seemingly possess chirality. Measurement was then carried out for four samples, the FP, achiral Perspex, and Perspex substrates with two variants of chiral ligands (L-Cysteine and D-Cysteine) attached to gold nanoparticles with Ø=4 . The FP, which possessed gyrotropic properties, has an apparent chirality which fluctuates between left and right-handed, however through further analysis this was found to be caused by the strong Fabry-Pérot reflections in the FP. The achiral SUT seemingly was a chiral SUT, as expected from the previous Jones’ matrix analysis, highlighting the uncertainty of this measurement scheme if used without first characterising the system. The two chiral enantiomer SUT were measured, both showed an increase in chirality, but these SUT did not show chirality of opposite handedness. Finally, two SUT were measured as a standard test SUT, these were two helix arrays with differing spacing between the helices. The results for this showed that the proposed methodology was able to measure a difference in the transmission of left-handed circular polarisation (LHCP) and right-handed circular polarisation (RHCP) as would be expected. When measuring with the original methodology by Dr Jhih-Hong Cheng, it was found that it was unable to measure this difference, highlighting the necessity in extraction of the SUT Jones’ matrix coefficients individually. The designed method could be utilised in the measurement of various organic and inorganic matter and devices, namely: proteins, peptides, and other biological matter exhibiting chiral properties; artificial materials with designed chirality; quasi-optical circuitry, and circularly polarised antennas

    Expression and localization of thylakoid-associated mRNAs during heterocyst development in cyanobacterium Anabaena sp. strain PCC 7120

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    Cyanobacteria are the only prokaryotes that perform oxygen-producing photosynthesis. Photosynthetic light reactions occur at the thylakoid membranes. In the filamentous cyanobacterium Anabaena sp. PCC 7120, thylakoids are remodelled during heterocyst development and the honeycomb domain is generated at the sub-polar region of the heterocysts with specific terminal oxidases (Cox proteins). Little is known about the remodelling of thylakoids during heterocyst development and the targeting of proteins to the specific membrane domain. In this study, RNA-Fluorescence in situ Hybridisation was used to investigate the sites of translation of thylakoid membrane proteins by probing mRNAs encoding membrane components in Anabaena sp. PCC 7120 during heterocyst development. The mRNA signals are concentrated in patches at the inner surface of the thylakoid membranes, facing the central cytoplasm. These patches mark the putative sites of translation and membrane insertion of these proteins. The localisation of cox mRNA and oxidase activity following nitrogen depletion was probed. cox mRNAs are evenly distributed over the inner surface of the thylakoid membranes, while oxidase activity is concentrated at the honeycomb thylakoids, suggesting that the oxidase proteins migrate extensively after translation to reach the location of their activity. The effect of specific RNA-binding proteins in mRNA expression and localisation was then studied. Rbp2 and Rbp3 were suggested to be involved in the targeting of photosynthetic mRNAs to the thylakoids in Synechocystis sp. PCC 6803. The deletion of rbpG, the closest homolog of Rbp3 in Anabaena sp. PCC 7120, shows a disrupted thylakoid membrane organisation with reduced Photosystem II activity and lower efficiency of the PSII repair cycle. The ΔrbpG mutant also shows significantly reduced cellular levels of photosynthetic mRNAs, particularly for psbA mRNA that encodes PSII D1 subunit. This suggests that the chaperoning of photosynthetic mRNAs by RbpG is important for the correct co-ordination of thylakoid protein translation and assembly

    Comparing accuracy of tomosynthesis plus digital mammography or synthetic 2D mammography in breast cancer screening: baseline results of the MAITA RCT consortium.

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    AIM: The analyses here reported aim to compare the screening performance of digital tomosynthesis (DBT) versus mammography (DM). METHODS: MAITA is a consortium of four Italian trials, REtomo, Proteus, Impeto, and MAITA trial. The trials adopted a two-arm randomised design comparing DBT plus DM (REtomo and Proteus) or synthetic-2D (Impeto and MAITA trial) versus DM; multiple vendors were included. Women aged 45 to 69 years were individually randomised to one round of DBT or DM. FINDINGS: From March 2014 to February 2022, 50,856 and 63,295 women were randomised to the DBT and DM arm, respectively. In the DBT arm, 6656 women were screened with DBT plus synthetic-2D. Recall was higher in the DBT arm (5·84% versus 4·96%), with differences between centres. With DBT, 0·8/1000 (95% CI 0·3 to 1·3) more women received surgical treatment for a benign lesion. The detection rate was 51% higher with DBT, ie. 2·6/1000 (95% CI 1·7 to 3·6) more cancers detected, with a similar relative increase for invasive cancers and ductal carcinoma in situ. The results were similar below and over the age of 50, at first and subsequent rounds, and with DBT plus DM and DBT plus synthetic-2D. No learning curve was appreciable. Detection of cancers >= 20 mm, with 2 or more positive lymph nodes, grade III, HER2-positive, or triple-negative was similar in the two arms. INTERPRETATION: Results from MAITA confirm that DBT is superior to DM for the detection of cancers, with a possible increase in recall rate. DBT performance in screening should be assessed locally while waiting for long-term follow-up results on the impact of advanced cancer incidence

    Endothelial Neuropilin-1: a multifaced signal transducer with an emerging role in inflammation and atherosclerosis beyond angiogenesis.

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    Neuropilin-1 (NRP1) is a transmembrane glycoprotein expressed by several cell types including, neurons, endothelial cells (ECs), smooth muscle cells, cardiomyocytes and immune cells comprising macrophages, dendritic cells and T cell subsets. Since NRP1 discovery in 1987 as an adhesion molecule in the frog nervous system, more than 2300 publications on PubMed investigated the function of NRP1 in physiological and pathological contexts. NRP1 has been characterised as a coreceptor for class 3 semaphorins and several members of the vascular endothelial growth factor (VEGF) family. Because the VEGF family is the main regulator of blood and lymphatic vessel growth in addition to promoting neurogenesis, neuronal patterning, neuroprotection and glial growth, the role of NRP1 in these biological processes has been extensively investigated. It is now established that NRP1 promotes the physiological growth of new vessels from pre-existing ones in the process of angiogenesis. Furthermore, several studies have shown that NRP1 mediates signalling pathways regulating pathological vascular growth in ocular neovascular diseases and tumour development. Less defined are the roles of NRP1 in maintaining the function of the quiescent established vasculature in an adult organism. This review will focus on the opposite roles of NRP1 in regulating transforming growth factor β signalling pathways in different cell types, and on the emerging role of endothelial NRP1 as an atheroprotective, anti-inflammatory factor involved in the response of ECs to shear stress

    Comparative Investigation of the Microstructure of MgCl2 Aqueous Solutions Using Different X-ray Scattering Sources, Raman Spectroscopy, and Atomistic Simulations.

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    Aqueous solutions of magnesium chloride (MgCl2(aq)) are often used to test advances in the theory of electrolyte solutions because they are considered an ideal strong 2:1 electrolyte. However, there is evidence that some ion association occurs in these solutions, even at low concentrations. Even a small ion-pairing constant can have a significant impact on the chemical speciation of ions, so it is important to determine whether ion pairing actually occurs. In this study, MgCl2(aq) with concentrations ranging from 1 to 35% was studied using three methods: X-ray scattering (XRS) with the Shanghai Synchrotron Radiation Facility (SSRF) and silver-anode laboratory sources, Raman spectroscopy, and molecular dynamics (MD) simulations with the COMPASS-II and Madrid force fields. XRS results were analyzed in the framework of PDF theory to obtain the reduced structure function F(Q) and the reduced pair distribution function G(r). The F(Q) values from synchrotron radiation and laboratory sources both showed that the tetrahedral hydrogen bonds in bulk water were destroyed with the increased MgCl2 concentration. The results of G(r) indicated that the main peaks centered at 2.05 and 2.80 Å can be ascribed to the interactions of Mg-O and O-O, respectively. The peak at 3.10 Å is attributed to the combined effect of O-O and Cl-O. By comparing the structural information on MgCl2 solution obtained from the two light sources, it was found that both SSRF and silver-anode laboratory sources can reflect the above-mentioned structural information on MgCl2 solution. The radial distribution function (RDF) obtained from MD simulations of MgCl2 solutions assigned the peaks at 2.0, 2.8, and 3.2 Å to the Mg-O, O-O, and Cl-O interatomic pairs, respectively. The decrease in the O-O coordination number confirms that the hydrogen-bonding network of water is disrupted by increasing MgCl2 observed by X-ray scattering. The proportion of Mg-Cl contact ion pairs gradually increases with MgCl2 concentration as does the coordination number. Raman spectroscopy results show that the bond type changes from double donor double acceptor (DDAA) to single donor-single acceptor (DA) with increasing concentration, providing explicit details of the hydrogen-bond evolution in the aqueous solution

    Local party members’ views are associated, but not completely congruent, with local constituency opinion

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    Do local political party members reflect the views of voters in their constituencies? Since candidate selection by local party members is the most common form of candidate selection in the United Kingdom, it is important to understand local party members’ views, and how those views relate to views in the local area. We investigate the degree to which individual members’ views match local opinion by combining the results of a large-scale survey of party members in the United Kingdom with estimates of local opinion created using multilevel regression and post-stratification. We find that individual party members’ views are moderately to strongly associated with local opinion on both left-right and liberty-authority dimensions. Even so, party members are not entirely congruent with opinion in the local area, having opinions which are either to the left or right of voters in their local area, and which are uniformly more liberal than party supporters

    Investigating the role of versican in immune exclusion in triple negative breast cancer

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    Triple negative breast cancer has the highest T cell infiltrate in comparison to other subtypes of breast cancer. To try to improve the anti-tumour response of these T cells, immunotherapy has been trialled, however clinical trials showed poor results. The response to immunotherapy in solid tumours is limited and this has been attributed to the presence of the extracellular matrix (ECM). The ECM can interact with T cells biochemically or physically, affecting their trafficking in the tumour. This can cause the restriction of T cells in the stroma limiting their contact with the tumour epithelial cells, leading to an immune excluded phenotype. Identifying key components of the ECM that are associated with the restriction of immune cells can provide potential targets that could be degraded to improve anti-tumour immunity. From previous work in the lab a signature of molecules were identified which were associated with immunosuppression. In the initial analysis of these molecules in a subset of TNBC tissues, versican (VCAN) was identified as an ECM component that associates with immune cell infiltration into the tumour epithelium. VCAN is a proteoglycan which has the glycosaminoglycan chondroitin sulphate (CS) attached to the peptide backbone. Through its multiple domains and glycan post-translational modifications, VCAN has been shown to have a role in inflammation and cancer progression. To study how VCAN may affect the trafficking of T cells, I first looked at how VCAN expression associated with immune excluded tissues. It was observed that VCAN levels were higher in the epithelial zone of excluded tissues compared to inflamed tissues. CS levels were then explored within the tissues where the sulphation patterns on CS in the stroma led to the discovery of CS-C being higher in excluded tissues and CS-A being higher in inflamed tissues. To observe this effect in-vitro, VCAN was enriched from TNBC and fibroblast cell line secretions. The effect of CS was tested through chondroitinase (CSase) treatment of VCAN enriched protein in a transwell model. An increase in invasion was observed following CSase treatment of protein with high levels of CS-C. To conclude, from the study I identified that within TNBC tissues the excluded immune phenotype associates with epithelial zone expressed VCAN which has a different CS sulphation pattern compared to inflamed tissues, and this difference in sulphation inhibits T-cell trafficking in in vitro models, which can be overcome through enzymatic digestion of the CS. Therefore, targeting VCAN by degrading CS may provide a way to drive excluded tumours into an inflamed and therapy responsive phenotype. Such an approach could be coupled with immunotherapy such as cell-based T-cell therapies


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