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In crystallo lattice adaptivity triggered by solid-gas reactions of cationic group 7 pincer complexes
Get PDFFunding: The EPSRC (EP/W015552, EP/W015498, DTP for J. C. G.), Wellcome Trust (206161/Z/17/Z); ARCHER2 UK National Supercomputing Service, Royal Society (J. M. L. INF\R1\221057).The group 7 complexes [M(κ3-2,6-(R2PO)2C5H3N)(CO)2L][BArF4] [M = Mn, R = iPr, L = THF; M = Re, R = tBu, L = vacant site] undergo in crystallo solid-gas reactivity with CO to form the products of THF substitution or CO addition respectively. There is a large, local, adaptive change of [BArF4] anions for M = Mn, whereas for M = Re the changes are smaller and also remote to the site of reactivity.Peer reviewe
On the structure of parasitic gravity-capillary standing waves in the small surface tension limit
Get PDFFunding: J.S. and P.H.T. acknowledge support by the Engineering and Physical Sciences Research Council (EPSRC grant no. EP/V012479/1). J.S. is additionally supported by the Engineering and Physical Sciences Research Council (EPSRC grant no. EP/W522491/1).We present new numerical solutions for nonlinear standing water waves when the effects of both gravity and surface tension are considered. For small values of the surface tension parameter, solutions are shown to exhibit highly oscillatory capillary waves (parasitic ripples), which are both time- and space-periodic, and which lie on the surface of an underlying gravity-driven standing wave. Our numerical scheme combines a time-dependent conformal mapping together with a shooting method, for which the residual is minimised by Newton iteration. Previous numerical investigations typically clustered gridpoints near the wave crest, and thus lacked the fine detail across the domain required to capture this phenomenon of small-scale parasitic ripples. The amplitude of these ripples is shown to be exponentially small in the zero surface tension limit, and their behaviour is linked to (or explains) the generation of an elaborate bifurcation structure.Peer reviewe
Enriching experience
Get PDFThe variety in human experience is enormous, even more so in potential. How do people enrich their experience of the world? Not every new experience enriches in the sense I’m after. Rather, I’m interested in experience that is novel, insofar as it adds to the repertoire of interaction with the world.
To describe how people interact with the world, in experience, I make use of the parallels in the work of John Haugeland and Alva Noë (a comparison absent from the literature). Both believe perception and thought are continuous in that all experience is skill based. They say experience is an activity, it consists in exercising the skills constitutive of the corresponding experiences as such. Both Haugeland and Noë call these skills understanding, meaning understanding is the practical ability to experience things in their possibility.
I conclude that people enrich their experience of the world through gaining novel forms of understanding."This work was supported by the Prins Bernhard Cultuurfonds (scholarship 40037945)."--Fundin
International Ocean Discovery Program Expedition 389 preliminary report : Hawaiian drowned reefs
Get PDFFunding: This publication was prepared by the European Consortium for Ocean Research Drilling (ECORD) Science Operator (ESO) and Texas A&M University (TAMU) as an account of work performed under the International Ocean Discovery Program (IODP). Funding for IODP is provided by the following international partners: National Science Foundation (NSF), United States; Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan; European Consortium for Ocean Research Drilling (ECORD); Ministry of Science and Technology (MOST), People’s Republic of China; Australia-New Zealand IODP Consortium (ANZIC); Ministry of Earth Sciences (MoES), India.Our understanding of the mechanisms controlling eustatic sea level and global climate changes has been hampered by a lack of appropriate fossil coral records over the last 500 ky, particularly into and out of the glacial periods. This problem was addressed by International Ocean Discovery Program Expedition 389 by drilling a unique succession of Hawaiian drowned coral reefs now at 110–1300 meters below sea level (mbsl). The four objectives are to investigate (1) the timing, rate, and amplitude of sea level variability to examine cryosphere and geophysical processes, including the assessment of abrupt sea level change events; (2) the processes that determine changes in mean and high-frequency (seasonal–interannual) climate variability from times with different boundary conditions (e.g., ice sheet size, pCO2, and solar forcing); (3) the response of coral reef systems to abrupt sea level and climate changes; and (4) the variation through space and time of the subsidence and the volcanic evolution of the island. To achieve these objectives, 35 holes at 16 sites ranging 131.9–1241.8 mbsl were drilled during the expedition. A total of 425 m of core was recovered, comprising reef (83%) and volcanic (17%) material. Average core recoveries were 66%, with numerous intervals characterized by very well preserved mixtures of coralgal and microbialite frameworks with recoveries >90%. Some science-critical shallow sites were not drilled due to a failure to secure permits to operate in Hawaiian state waters. Furthermore, apart from one site the target penetration depths were not achieved. Preliminary radiometric dates indicate that the recovered reef deposits are from 488 to 13 ka in age. The Onshore Science Party took place in February 2024. Cores were CT and hyperspectral scanned and described. Standard measurements were made, and samples were taken for postcruise research. Preliminary assessment of the age and quality of the reef and basalt cores suggest that many of the expedition objectives will be met
Emotions, language and storytelling : exploring the liberative theology of Marianne Katoppo
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Rethinking revelation in Hindu-Christian dialogue : engaging with selected works of Raimon Panikkar's Opera Omnia
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Swimming to the Moon: truth, fiction, memory, and a memoir. A childhood and its exegesis
No full textThis thesis examines both the loss and partial reclamation of agency, identity, and coherence. Matching a stand-alone memoir of a fractured childhood to a short exegesis, which interrogates the concept of memory, the price sexual abuse, parental absence, and dissociation impose on recall, the debts memoirists owe both living and dead, the writing of the memoir, and the complex relationship between the character writing, the character being written about, and the other behind the curtain, writing both.
Opening, aged six, on a sunlit beach in Malta, and closing thirteen years later on moonlit rocks in Oslo fjord, its scenes bracket a childhood (seen from then and now, in respectively third person and first), which, being sixty years distant, is as much history of political, philosophical, and cultural change, as current.
In the naming of the act, and the acceptance of its price - but also in acknowledging the hinterland of maladaptive daydreaming, and so a lifelong career as a novelist that this particular fracturing brings - the creative strives through narrative structure to mirror the splintering found in complex trauma, while the exegesis considers whether memory, splintered or not, can in any real sense be accurate, and whether the self (on, or off the page), can in any sense be said to be real
Loneliness, social isolation and social capital of ethnic minority/immigrant older adults : a mixed methods investigation
No full textThis thesis explores loneliness and social isolation among ethnic minority/immigrant older adults, investigating how ethnicity/immigration intersects with other important social positions—such as age, gender, and socio-economic status—to shape their experiences. It also explores the role of social resources—social networks, social support, and social capital—in mitigating these challenges. Using a mixed methods approach, the thesis integrates a systematic scoping review, statistical analyses of two national survey datasets, and qualitative interviews. This thesis comprises four components: 1) A scoping review of 76 journal articles, identifying five critical gaps and mapping factors of loneliness and social isolation within a multidimensional socio-ecological framework. 2) A latent class analysis of the English Longitudinal Study of Ageing, uncovering four heterogeneous loneliness trajectories in the COVID-19 pandemic compared to pre-pandemic among older adults in England. 3) A binary logistic regression analysis of the Evidence for Equality National Survey, examining the interplay of racism, social capital, and loneliness among Chinese, Indian, and Pakistani communities in the UK. 4) In-depth qualitative interviews with 20 ethnic minority/immigrant older adults and eight third-sector key informants, exploring their lived experiences over the life course. Findings demonstrate significant heterogeneity within ethnic minority/immigrant older populations, highlighting the diversity of their experiences with loneliness, social isolation and social capital. Ethnicity/immigration intersects with other critical social positions to shape their vulnerabilities. Ethnic minority/immigrant older adults actively mobilise social resources to combat loneliness, but structural barriers, such as racism and socio-economic inequalities, often undermine their efforts. This thesis underscores the urgent need to address social dimensions of ageing in diverse populations. By illuminating the multidimensional and intersectional nature of these experiences, it provides insights for targeted, equity-focused solutions that integrate individual agency with structural change to fostering social and emotional wellbeing for all older adults
Cryo-EM structure of the conjugation H-pilus reveals the cyclic nature of the TrhA pilin
Get PDFFunding: We would like to acknowledge Diamond for accessand support of the cryo- EM facilities at the UK National Electron Bio-Imaging Centre under visit BI33230. This project made use of the Computing Platformfor Electron Microscopy at Imperial College funded by the BBSRC Mid-range equipment Initiative 22ALERT (BB/X019284/1). N.I. is funded by a Fellowship from The Naito Foundation. C.S. was funded by a Biotechnology and Biological Sciences Research Council Doctoral Training Program Studentship grant (BB/M011178/1). E.H.E. was funded by NIH GM122510. O.W.-P. is supported by a Schrödinger PhD scholarship.Conjugation, the major driver of the spread of antimicrobial resistance genes, relies on a conjugation pilus for DNA transfer. Conjugative pili, such as the F-pilus, are dynamic tubular structures, composed of a polymerized pilin, that mediate the initial donor–recipient interactions, a process known as mating pair formation (MPF). IncH are low-copy-number plasmids, traditionally considered broad host range, which are found in bacteria infecting both humans and animals. The reference IncHI1 plasmid R27, isolated from Salmonella enterica serovar Typhi, encodes the conjugative H-pilus subunit TrhA containing 74 residues after cleavage of the signal sequence. Here, we show that the H-pilus forms long filamentous structures that mediate MPF and describe its cryoelectron-microscopic (cryo-EM) structure at 2.2 Å resolution. Like the F pilus, the H-pilin subunits form helical assemblies with phospholipid molecules at a stoichiometric ratio of 1:1. While there were previous reports that the T-pilus from Agrobacterium tumefaciens was composed of cyclic subunits, three recent cryo-EM structures of the T-pilus found no such cyclization. Here, we report that the H-pilin is cyclic, with a covalent bond connecting the peptide backbone between the N and C termini. Both the cryo-EM map and mass spectrometry revealed cleavage of the last five residues of the pilin, followed by cyclization via condensation of the amine and carboxyl residues. Mutagenesis experiments revealed that loss of cyclization abolished pilus biogenesis and efficient plasmid transfer. The cyclic nature of the pilin could stabilize the pilus and may explain the high incidence of IncH plasmid dissemination.Peer reviewe
Dive-by-dive variation in the diving respiratory air volume of southern elephant seals (Mirounga leonina)
Get PDFFunding: This study was supported by grants from the Office of Naval Research N00014-18-1- 2822, DoD SERDP contract W912HQ20C0056, IPEV (Institut Paul Emile Victor). The Carnegie Trust for the Universities of Scotland (PHD012719) provided support to G.S.The role of diving respiratory air volume (DRAV) in deep-diving phocid seals remains poorly understood, largely because of the lack of methods for measuring DRAV in free-ranging divers that exhale before diving. We developed a method to estimate DRAV using a hydrodynamic glide model applied to descent glides recorded using multi-sensor data loggers. We estimated dive-by-dive DRAV for six negatively buoyant female southern elephant seals (Mirounga leonina). During shallow descent glides, rapid compression of DRAV influenced net buoyancy and gliding speed, making this phase suitable for estimating DRAV. Our results revealed dive-by-dive variation in DRAV, which was positively correlated with root mean square (RMS) sway acceleration (a proxy for per-stroke effort) and the depth at which gliding began during the initial descent. DRAV increased with both tissue density and maximum dive depth, suggesting that seals adjusted their DRAV to stay closer to neutral buoyancy through their dives. However, the observed level of adjustment did not result in neutral buoyancy at half of the maximum dive depth, as predicted to minimise round-trip locomotion costs. Instead, the seals typically adjusted DRAV to reach neutral buoyancy at ∼30 m depth, <10% of their mean maximum dive depth. This indicates that strong negative tissue density imposes transit costs that cannot be fully compensated for by DRAV adjustment alone. Future work should explore whether other breath-hold divers show similar patterns of DRAV adjustment and quantify the associated physiological and ecological benefits.Peer reviewe
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