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This work will present experimental results on two projects measuring the electronic properties of unconventional superconductors. The first project focuses on the iron-based superconductor system of FeSe1-xSx. We used scanning tunneling microscopy/spectroscopy (STM/S) to make detailed measurements of the electronic states of tetragonal FeSe0.89S 0.19. We also performed theoretical band structure calculations that were calibrated by angle-resolved photoemission spectroscopy measurements for comparison. We utilize the high spatial resolution of the STM/S measurements to separately analyze modulations in the local density of states (LDOS) in regions near and away from iron-vacancies. This analysis revealed two types of features: (i) energy dispersive quasiparticle interference patterns which can explained by our band structure calculations and (ii) a much stronger modulation just above the Fermi level centered at q=0.12 Å-1 which does not disperse with energy and cannot be explained by our band structure model. Local rotational symmetry analysis shows that while the modulations are four-fold symmetric on average, they are actually comprised of small domains with two-fold symmetry. Statistical analysis demonstrates that the boundaries of these domains are spatially correlated with the locations of iron-vacancies. The second project studies charge order in the La-based cuprate La1.475Nd0.4Sr0.125CuO4. We performed temperature and uniaxial strain dependent resonant x-ray scattering studies on the charge order and the low-temperature orthorhombic to low-temperature tetragonal (LTO-LTT) structural transition. Before applying any strain, we found a precursor charge order peak existing up to 200 K, well above the static charge order onset temperature. Upon applying uniaxial tensile strain of about 0.1%, we observed a reduction in the onset of charge order by 50 K and a 20 K reduction in the LTO-LTT transition temperature. We also saw a preference for the charge order to form

FeSe1-xSx remains one of the most enigmatic systems of Fe-based superconductors. While much is known about the orthorhombic parent compound, FeSe, the tetragonal samples, FeSe1-xSx with x > 0.17, remain relatively unexplored. Here, we provide an in-depth investigation of the electronic states of tetragonal FeSe0.81S0.19, using scanning tunneling microscopy and spectroscopy (STM/S) measurements, supported by angle-resolved photoemission spectroscopy (ARPES) and theoretical modeling. We analyze modulations of the local density of states (LDOS) near and away from Fe vacancy defects separately and identify quasiparticle interference (QPI) signals originating from multiple regions of the Brillouin zone, including the bands at the zone corners. We also observe that QPI signals coexist with a much stronger LDOS modulation for states near the Fermi level whose period is independent of energy. Our measurements further reveal that this strong pattern appears in the STS measurements as short range stripe patterns that are locally two-fold symmetric. Since these stripe patterns coexist with four-fold symmetric QPI around Fe-vacancies, the origin of their local two-fold symmetry must be distinct from that of nematic states in orthorhombic samples. We explore several aspects related to the stripes, such as the role of S and Fe-vacancy defects, and whether they can be explained by QPI. We consider the possibility that the observed stripe patterns may represent incipient charge order correlations, similar to those observed in the cuprates.

Environmentally mediated indirect pathogen transmission is linked to host movement and foraging in areas where pathogens are maintained in the environment. In the case of anthrax, spores of the causative bacterium Bacillus anthracis are released into the environment following host death and create locally infectious zones (LIZs) around carcass sites; by grazing at LIZs, herbivores are potentially exposed to spores. Here, we used camera traps to assess how ungulate species use carcass sites in southwestern Montana and evaluated how these behaviours may promote indirect anthrax transmission, thus providing, to our knowledge, the first detailed documentation and study of the fine-scale mechanisms underlying foraging-based disease transmission in this ecosystem. We found that carcasses at LIZs significantly increased aboveground biomass of vegetation and concentrations of sodium and phosphorus, potentially making these sites more appealing to grazers. Host behavioural responses to LIZs varied depending on species, sex, season and carcass age; but, overall, our results demonstrated that carcasses or carcass sites serve as an attractant to herbivores in this system. Attraction to LIZs probably represents an increased risk of exposure to B. anthracis and, consequently, increased anthrax transmission rates. Accordingly, continued anthrax surveillance and control strategies are critical in this system.

Environmentally mediated indirect pathogen transmission is linked to host movement and foraging in areas where pathogens are maintained in the environment. In the case of anthrax, spores of the causative bacterium Bacillus anthracis are released into the environment following host death and create locally infectious zones (LIZs) around carcass sites; by grazing at LIZs, herbivores are potentially exposed to spores. Here, we used camera traps to assess how ungulate species use carcass sites in southwestern Montana and evaluated how these behaviours may promote indirect anthrax transmission, thus providing, to our knowledge, the first detailed documentation and study of the fine-scale mechanisms underlying foraging-based disease transmission in this ecosystem. We found that carcasses at LIZs significantly increased aboveground biomass of vegetation and concentrations of sodium and phosphorus, potentially making these sites more appealing to grazers. Host behavioural responses to LIZs varied depending on species, sex, season and carcass age; but, overall, our results demonstrated that carcasses or carcass sites serve as an attractant to herbivores in this system. Attraction to LIZs probably represents an increased risk of exposure to B. anthracis and, consequently, increased anthrax transmission rates. Accordingly, continued anthrax surveillance and control strategies are critical in this system.

Environmentally mediated indirect pathogen transmission is linked to host movement and foraging in areas where pathogens are maintained in the environment. In the case of anthrax, spores of the causative bacterium Bacillus anthracis are released into the environment following host death and create locally infectious zones (LIZs) around carcass sites; by grazing at LIZs, herbivores are potentially exposed to spores. Here, we used camera traps to assess how ungulate species use carcass sites in southwestern Montana and evaluated how these behaviours may promote indirect anthrax transmission, thus providing, to our knowledge, the first detailed documentation and study of the fine-scale mechanisms underlying foraging-based disease transmission in this ecosystem. We found that carcasses at LIZs significantly increased aboveground biomass of vegetation and concentrations of sodium and phosphorus, potentially making these sites more appealing to grazers. Host behavioural responses to LIZs varied depending on species, sex, season and carcass age; but, overall, our results demonstrated that carcasses or carcass sites serve as an attractant to herbivores in this system. Attraction to LIZs probably represents an increased risk of exposure to B. anthracis and, consequently, increased anthrax transmission rates. Accordingly, continued anthrax surveillance and control strategies are critical in this system.

Environmentally mediated indirect pathogen transmission is linked to host movement and foraging in areas where pathogens are maintained in the environment. In the case of anthrax, spores of the causative bacterium Bacillus anthracis are released into the environment following host death and create locally infectious zones (LIZs) around carcass sites; by grazing at LIZs, herbivores are potentially exposed to spores. Here, we used camera traps to assess how ungulate species use carcass sites in southwestern Montana and evaluated how these behaviours may promote indirect anthrax transmission, thus providing, to our knowledge, the first detailed documentation and study of the fine-scale mechanisms underlying foraging-based disease transmission in this ecosystem. We found that carcasses at LIZs significantly increased aboveground biomass of vegetation and concentrations of sodium and phosphorus, potentially making these sites more appealing to grazers. Host behavioural responses to LIZs varied depending on species, sex, season and carcass age; but, overall, our results demonstrated that carcasses or carcass sites serve as an attractant to herbivores in this system. Attraction to LIZs probably represents an increased risk of exposure to B. anthracis and, consequently, increased anthrax transmission rates. Accordingly, continued anthrax surveillance and control strategies are critical in this system.

We report a combined photocatalytic and hydrogen atom transfer (HAT) approach for the light-mediated epimerization of readily accessible piperidines to provide the more stable diastereomer with high selectivity. The generality of the transformation was explored for a large variety of di- to tetrasubstituted piperidines with aryl, alkyl, and carboxylic acid derivatives at multiple different sites. Piperidines without substitution on nitrogen as well as N-alkyl and aryl derivatives were effective epimerization substrates. The observed diastereoselectivities correlate with the calculated relative stabilities of the isomers. Demonstration of reaction reversibility, luminescence quenching, deuterium labeling studies, and quantum yield measurements provide information about the mechanism.

Highly functionalized aminocyclopentadienes can be formed through the rearrangement of anions generated from readily prepared 6-silyl-1,2-dihydropyridines by desilylation with fluoride. The scope and generality of the reaction was defined, and diverse transformations were performed on the highly functionalized products. A mechanism and driving force for the rearrangement were identified from experiments and DFT calculations.

An enantioconvergent Friedel–Crafts alkylation of indoles with donor–acceptor cyclopropanes is described. The reaction is catalyzed by pybox•MgI2 and proceeds via a type I dynamic kinetic asymmetric transformation (DyKAT).

An enantioconvergent Friedel–Crafts alkylation of indoles with donor–acceptor cyclopropanes is described. The reaction is catalyzed by pybox•MgI2 and proceeds via a type I dynamic kinetic asymmetric transformation (DyKAT).

An enantioconvergent Friedel–Crafts alkylation of indoles with donor–acceptor cyclopropanes is described. The reaction is catalyzed by pybox•MgI2 and proceeds via a type I dynamic kinetic asymmetric transformation (DyKAT).

The findings of school survey responses collected in June and July 2021 that examined the preparations for the roll-out of the Curriculum for Wales. Detail is offered to inform policy and support schools.

The findings of qualitative research with 48 senior leaders and practitioners in schools and Pupil Referral Units in Wales examine preparations for the roll out of the Curriculum for Wales.

This report presents findings of a scoping study relating to the evaluation of the curriculum and assessment reforms in Wales. The Curriculum for Wales is the cornerstone of the Welsh Government’s efforts to reform education in Wales and build an education system that raises educational standards and enjoys public confidence. Under the reforms each school is developing its own curriculum, supported by national guidance. The aim of the scoping study is to articulate the theory, assumptions, evidence and readiness underpinning the curriculum and assessment reforms and to use this information to develop recommendations for a robust monitoring and evaluation programme.