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A simple [2 + 2] photocycloaddition reaction that proceeds in an NMR tube, illuminated by daylight
Get PDFThis work presents a simple and small-scale procedure that demonstrates the use of daylight to promote a photochemical [2 + 2] cycloaddition reaction. Previous related experimental protocols used in teaching laboratories have been focused on the preparation of “Cookson’s ketone” (pentacyclo-[5.4.0.02,6.03,10.05,9]undecane-8,11-dione). These approaches require an initial Diels–Alder reaction of cyclopentadiene and 1,4-benzoquinone, followed by an ultraviolet (UV) light-promoted intramolecular [2 + 2] cycloaddition reaction. This Laboratory Experiment highlights an alternative approach, where an analogue of Cookson’s ketone is readily prepared on a small scale from a stable diene and the photochemical [2 + 2] reaction proceeds in an NMR tube illuminated by daylight. The synthesis and NMR experiments described have been used in an advanced-level university laboratory course as an example of photochemical synthesis and use of 1D and 2D NMR spectroscopy to monitor reaction progress.Peer reviewe
Tree rings and volcanoes : the climate of NW North America
No full textThis thesis aimed to refine temperature reconstruction strategies for Northwest North America (NWNA), introducing new applications of the latewood blue intensity parameter (LWBI), and pooling multiple regional datasets to create a new millennial-length temperature reconstruction. Currently, NWNA is underrepresented by long tree records in comparison to Eurasia. Such records are crucial for contextualizing modern warming in the context of past variability.
The NWNA region represents the origin of the “Divergence Problem”, a phenomenon referring to the loss/weakening of temperature sensitivity over time. To address this, a strategy was developed, using a network of sites in the southern Yukon, to minimise its impact and optimise the temperature signal. Trees growing within 100m of upper treeline provide the most temporally stable signal, making them the optimal targets for a temperature reconstruction.
The successful use of LWBI for developing temperature reconstructions is well-documented, yet its application for dating is less understood. LWBI was utilised to absolutely date the 9th century Mt. Churchill eruption for the first time using dendrochronological techniques, a result not possible using RW. By demonstrating that LWBI can be effectively used for crossdating between species, dated subfossil trees preserved in the volcanic ash placed the eruption between 852-853 CE.
The final LWBI reconstruction provided temperature variability for NWNA back to the 3rd century CE. While full period modelling (1901-2014) explained 46% of the temperature variance, the fidelity of the reconstruction reduced significantly prior to 933 CE due to decreased replication and significant underestimation of extreme warm season years was noted. The NWNA BI-based reconstruction demonstrates the most time stable temperature signal compared to other NWNA reconstructions but struggles to capture long term trends. Future research should integrate these data for a multi-parameter reconstruction for a more comprehensive, robust reflection of NWNA temperature variability
‘A thing like God’ : re-reading Gothic Philippians 2.6-8
Get PDFFunding: This publication was made possible through the support of a grant from the John Templeton Foundation.The Gothic translation of Phil 2.6–8 differs from the Greek in three ways: it says that Christ did not think it robbery to be ‘like God’; it breaks the parallelism between the ‘form of God’ and ‘form of a slave’; and it states explicitly that Christ was obedient ‘to the Father’. Scholars have focused exclusively on the first element, crediting it to the Homoian ‘Arian’ prejudices of the translator, Wulfila, or to his opposition to modalist tendencies in pro-Nicene thought of the 340s. Neither interpretation is satisfactory, the first because the Gothic displays no generalised Homoian bias, the second on philological grounds. When the passage is viewed as a whole, an explanation can be found in the history of exegesis. Homoian churchmen, who followed a theology close to the elderly Wulfila’s, seem to have construed ἁρπαγμός (Gothic wulwa, English ‘robbery’) as res rapienda, in the typology developed by N.T. Wright. Christ did not ‘seize’ equality with God. Incompatible with this view, the Gothic is a better fit for res retinenda (Christ did not ‘hold fast’ his divine status). In an ancient analogue to modern ‘functional equivalence’, it is representing the meaning of the text, as agreed among Greek exegetes, on the translation’s surface. Just why Wulfila did this remains obscure: certainly to clarify the passage’s Christology, but possibly also to head off misinterpretation in his Gothic context. Either way, the Gothic text shows a more flexible approach to translation than scholarship, still focused on stereotyped ‘Arianism’ and lexical equivalence, has yet recognised.Peer reviewe
Distribution and transmission of M. tuberculosis in a high-HIV prevalence city in Malawi : a genomic and spatial analysis
Get PDFFunding: Funding: MHC, ELC, VN, SB, CC, JRA, PGTC, PJD, DME, MF, YL, JL, NAM, JLW, JAS, TC acknowledge funding from the National Institute of Allergy and Infectious Diseases (NIAID) (R01AI147854) (https://www.niaid.nih.gov/). JWI-E acknowledges funding from the Bill & Melinda Gates Foundation (INV-006733, INV-002606) (https://www.gatesfoundation.org/) and the MRC Centre for Global Infectious Disease Analysis (reference MR/X020258/1), funded by the UK Medical Research Council (MRC)(https://www.ukri.org/councils/mrc/). This UK funded award is carried out in the frame of the Global Health EDCTP3 Joint Undertaking.Delays in identifying and treating individuals with infectious tuberculosis (TB) contribute to poor health outcomes and allow ongoing community transmission of M. tuberculosis (Mtb). Current recommendations for screening for tuberculosis specify community characteristics (e.g., areas with high local tuberculosis prevalence) that can be used to target screening within the general population. However, areas of higher tuberculosis burden are not necessarily areas with higher rates of transmission. We investigated the transmission of Mtb using high-resolution surveillance data in Blantyre, Malawi. We extracted and performed whole genome sequencing on mycobacterial DNA from cultured M. tuberculosis isolates obtained from culture-positive tuberculosis cases at the time of tuberculosis (TB) notification in Blantyre, Malawi between 2015-2019. We constructed putative transmission networks identified using TransPhylo and investigated individual and pair-wise demographic, clinical, and spatial factors associated with person-to-person transmission. We found that 56% of individuals with sequenced isolates had a probable transmission link to at least one other individual in the study. We identified thirteen putative transmission networks that included five or more individuals. Five of these networks had a single spatial focus of transmission in the city, and each focus centered in a distinct neighborhood in the city. We also found that approximately two-thirds of inferred transmission links occurred between individuals residing in different geographic zones of the city. While the majority of detected tuberculosis transmission events in Blantyre occurred between people living in different zones, there was evidence of distinct geographical concentration for five transmission networks. These findings suggest that targeted interventions in areas with evidence of localized transmission may be an effective local tactic, but will likely need to be augmented by city-wide interventions to improve case finding to have sustained impact.Peer reviewe
God as moral anti-exemplar in Spinoza
Get PDFThis paper addresses the question of whether Spinoza subscribes to moral exemplarism, defined as any moral theory including the idea that it is morally good, right, virtuous, praiseworthy, or obligatory to emulate certain figures identified as moral exemplars. The answer is given at multiple levels. At one level, Spinoza endorsed moral exemplarism as a descriptive theory of how we make moral judgements, but does not endorse those judgements. At another level he endorses judgements of good and bad based on conformity to a constructed exemplar of human nature, although the endorsement is perhaps pragmatic rather than moral. At a third level, Spinoza offers as the highest ethical ideal the emulation of God. But since Spinoza’s God is a being devoid of goals and even of any determinate character, emulating it seems to mean rejecting the whole ethical project of trying to find an exemplar to guide one’s moral choices and development.Peer reviewe
Printing persuasion : early eighteenth-century advertising in provincial England and Dublin
No full textIn 1695, the Licencing Act which had largely limited English printing to London, Oxford and Cambridge expired. The collapse of England’s London centric censorship laws stimulated the development of the provincial press. Newspaper printers were among the first to take advantage of the lack of government oversight. By the middle of the eighteenth-century, regional newspapers were a common sight in large towns across England. In Ireland, a thriving newspaper press developed in Dublin, as well as key provincial cities including Belfast, Cork and Limerick. In London, rivalry between Tory and Whig factions incentivised politicians to purchase newspapers to further their own political causes. Other titles were subsidised by London booksellers who utilised them as a vehicle to promote their own products.
Provincial newspapers lacked these additional revenue streams. Instead, they relied on the placement of advertisements to enhance the income generated directly from sales, creating a rich source of data through which to understand the retail revolution and provincial culture. Newspaper advertisements are of additional importance as provincial newspapers only infrequently carried regional news. Advertisements were frequently the only source of data provided within provincial newspapers that can provide insight into newspaper readers, printers, advertisers and local communities. This dissertation will proceed by recording and analysing a range of newspaper advertisements placed between the end of the licencing act and 1750.
Chapter 1 analyses book advertisements. The prominence of religious texts as a genre, and relative lack of works on contemporary politics, tells us much about readers in the early portion of the eighteenth-century. In chapter 2, advertisements for retail products and other services are discussed. Higher levels of advertising found to have occurred in coastal communities and those with burgeoning industrial sectors. In chapter 3 the importance of patent medicine is explored. We find evidence for locally sourced medicines, while claims that newspapers were geared towards medicines dealing with venereal disease are refuted. Chapter 4 combines analysis of property advertisements and official notices, advertisements placed by individuals and local authorities whose intention was to inform. The chapter demonstrates how property advertisements provide sources of local news, in addition to demonstrating a continued taste for acquiring large country estates in a world in which luxurious, portable retail items were becoming more commonplace. Chapter 5 deals with lost property and missing people and examines claims that newspaper adverts paved the way for a surveillance state. I demonstrate that advertisements tracked goods and people over large distances, though the fact that adverts monitored thieves and British soldiers deserting in Ireland demonstrate that advertisements did not simply lead to a more oppressive society.
The thesis concludes that advertisements can be broadly placed into two categories: advertisements which advertised products and services and notices placed by individuals and local authorities which were designed to inform. Retail advertisements played a part in advertising the novel goods produced because of the consumer revolution, regional advertisements were also a convenient medium for promoting traditional entertainments, products and agriculture land. The advertising sections of the newspapers reveal a world in which commerciality and advertising was increasingly accepted, but for blood sports and estate sales as much as for patent medicines and the latest books
Prioritising authenticity in live lecture comprehension pre-sessional assessment task design
Get PDFWhere pre-sessional assessments determine student progression, authenticity is crucial to deliver construct validity and support high-stakes progress decisions. However, replicating the natural processes that occur in academic environments poses challenges relating to domain representation and test-taker engagement as well as meeting stakeholder needs such as benchmarking against commercial tests. The current study reports on a project devised to develop an authentic lecture assessment for a pre-sessional programme, informed by a university-wide needs analysis. In the study, 66 students completed a live lecture comprehension task, and data were analysed using classical test theory and many facet Rasch measurement. In addition, students completed a questionnaire which was analysed using stepwise linear regression. Analysis of the lecture transcript was completed to evaluate the suitability of the content for the target level. Results showed that speech rate and vocabulary were appropriate for the assessment objectives, student self-reported comprehension accounted for some test score variance, and the test was reliable. However, many facet Rasch measurement showed the test was only able to categorise test takers into two distinct levels, which was problematic as the pre-sessional needed to multiple levels for schools to make admissions decisions. Recommendations for balancing these challenges in assessment design are presented.Peer reviewe
The singlet excited states of fulvene and of its 6,6-dimethyl derivative : a combined study of their energy levels by absorption spectroscopy, configuration interaction, and density functional calculations
Get PDFThe ultraviolet and vacuum ultraviolet (VUV) photo absorption spectra of fulvene were reconsidered by a combination of configuration interaction and density functional methods and extended to the newly acquired VUV photo absorption spectrum of the 6,6-dimethylfulvene derivative, where several Rydberg states have been identified. Singlet states of fulvene were studied using multi-root multi-reference configuration interaction with the H2C unit either coplanar with, or perpendicular to the ring. In contrast to ethylene, the lowest states are coplanar. The vibrational structure of the lowest (1B2) excited states of fulvene is well reproduced by calculated values. The second singlet state of fulvene, previously assigned as 1A1 on the basis of intensity, is incompatible with the calculated planar 1A1 state, which itself is a saddle point. This state shows significant quartic character on bending, and the best interpretation of the observed UV band of fulvene is of a bent form. The UV spectral state with low onset intensity is probably a 1B1 state of CS symmetry. Theoretical Rydberg states were determined for fulvene; the closest fit to the two known Rydberg states is to the 3p and 4p states (1B1). Comparison of the separation of the 2A2 and 2B1 states in the photoelectron spectra of the two compounds, with the threshold photoelectron spectrum of fulvene, shows that the 2B1 state vibrational structure is largely lost for both molecules. A reconsideration of the interaction between the X2A2 and A2B1 ionic states has led to the identification of the 4A2 quartic state of fulvene.Peer reviewe
Divination and philosophy in the letters of Paul
Get PDFThis book analyses the apostle Paul’s claims to receive and interpret knowledge from divine sources within the context of divination in the Graeco-Roman world. Each chapter studies a particular aspect of divination in Paul’s letters in comparison with similar phenomena in the Graeco-Roman world, dealing in turn with the underlying logic of divination (in the context of ancient philosophical conversations), visionary experience, prophecy and divine speech, the divinatory use of texts and the interpretation of signs. As such, the book forms an in-depth study of divine communication in Paul’s letters, integrating this theme with the broader topics of cosmology, anthropology, eschatology and theology. While New Testament texts and early Christian figures have traditionally been studied from the vantage point of theological categories (such as ‘revelation’) that isolate early Christianity from its historical context in the Graeco-Roman world, this book re-reads Paul’s thought and practice concerning divine communication within, not against, the Graeco-Roman thought and practice of divination. In doing so it illuminates the coherence and connections both between Paul and his historical context and between diverse topics of Paul’s letters that have usually been studied in isolation from each other
An updated evolutionary classification of CRISPR–Cas systems including rare variants
Get PDFFunding: K.S.M., S. A. Shmakov, Y.I.W., P.M., D.H.H. and E.V.K. are supported through the Intramural Research Program of the National Institutes of Health of the USA (National Library of Medicine). S. A. Shmakov is supported by funding of the Basic Research Program by the National Research University Higher School of Economics. C.L.B. is supported by European Research Council grants 865973 and 101158249. D.C. and J.T. are supported by Arbor Biotechnologies. P.H. is supported by IFF. S.M. was supported by funding from the Natural Sciences and Engineering Research Council of Canada (Discovery program) and holds a Tier 1 Canada Research Chair in Bacteriophages. F.J.M.M. is supported by the grants PID2023-150750NB-I00 (funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU), PROMETEU/2021/057 (funded by Conselleria d’Educació, Cultura, Universitats i Ocupació, Generalitat Valenciana, Spain) and INNEST/2024/427 (funded by Agencia Valenciana de Innovación—IVACE + I Innovación—and by the European Union through the ERDF Program of the Valencian Community 2021–2027). P.P. receives funding from the EMBC under EMBO Installation Grant (5342-2023) and is supported by the LMT under the ‘University Excellence Initiatives’ (measure number 12-001-01-01-01, project S-A-UEI-23-10). R.P.-R. is supported by a Lundbeck Fonden grant (R347-2020-2346) and a research grant from VILLUM FONDEN (VIL60763). S. A. Shah is a recipient of a Novo Nordisk Foundation project grant in basic bioscience (NNF18OC0052965). C.V. is supported by intramural funds of the Vilnius University. M.P.T. is supported by the National Institutes of Health (grant R35GM118160). A.F.Y. is supported by an Environmental Biotechnology Innovation Centre (EBIC), UKRI Engineering Biology Mission Hub grant (BB/Y008332/1). F.Z. is supported by Howard Hughes Medical Institute; Yang Tan Collective; Broad Institute Programmable Therapeutics Gift Donors; Pershing Square Foundation, William Ackman, and Neri Oxman; Phillips family; J. and P. Poitras; B.T. Charitable Trust. R. Backofen is supported by the German Research Foundation (SFB 1597/1 ‘Small Data’.The known diversity of CRISPR–Cas systems continues to expand. To encompass new discoveries, here we present an updated evolutionary classification of CRISPR–Cas systems. The updated CRISPR–Cas classification includes 2 classes, 7 types and 46 subtypes, compared with the 6 types and 33 subtypes in our previous survey 5 years ago. In addition, a classification of the cyclic oligoadenylate-dependent signalling pathway in type III systems is presented. We also discuss recently characterized alternative CRISPR–Cas functionalities, notably, type IV variants that cleave the target DNA and type V variants that inhibit the target replication without cleavage. Analysis of the abundance of CRISPR–Cas variants in genomes and metagenomes shows that the previously defined systems are relatively common, whereas the more recently characterized variants are comparatively rare. These low abundance variants comprise the long tail of the CRISPR–Cas distribution in prokaryotes and their viruses, and remain to be characterized experimentally.Peer reviewe
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