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Cool gas in the circumgalactic medium of massive post starburst galaxies
Get PDFFunding: VW acknowledges Science and Technologies Facilities Council (STFC) grant ST/Y00275X/1 and Leverhulme Fellowship RF-2024-589/4.Observing the interplay between galaxies and their gaseous surroundings is crucial for understanding how galaxies form and evolve, including the roles of long-lived cool gas reservoirs, starburst and AGN driven outflows. We use stacked Mg ii absorption lines in the spectra of background quasars to study the cool gas out to 9 Mpc from massive quiescent, star-forming and post-starburst galaxies with stellar masses log10(M∗/M⊙) ≳ 11 and 0.4 ≲ z ≲ 0.8 selected from the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS galaxies. Consistent with previous studies, we observe a decline in absorption strength indicating a decrease in cool gas content with increasing distance from the galaxies, as well as decreasing star formation rate of the galaxies. Beyond 1 Mpc, this decline levels off to the same absorption strength in all galaxy types, suggesting a transition from the circumgalactic medium (CGM) to the intergalactic medium (IGM) at approximately the virial radius of the host dark matter haloes. We find that post-starburst galaxies, that have experienced a recent burst of star formation that has rapidly quenched, exhibit significantly stronger Mg ii absorption within at least ∼300 kpc than star-forming or quiescent galaxies of the same stellar mass. Because post-starburst galaxies are a potentially significant pathway for the formation of quiescent elliptical galaxies, our results have wide reaching implications for understanding the mechanisms involved in quenching star formation in galaxies. We speculate that the excess cool gas absorption around post-starburst galaxies is related to their observed high velocity (∼1000 km/s) cool gas outflows. Thus, strong, short-lived bursts of star formation impact the CGM around galaxies on 100’s of kpc distances and Gyr timescales.Peer reviewe
Rapid sexual signal diversification is facilitated by permissive females
Get PDFFunding: This research was supported by funding from the UK Natural Environment Research Council to N.W.B. (NE/W001616/1) and to N.W.B. and J.G.R. (NE/T000619/1) and from the China Scholarship Council – University of St Andrews PhD scholarship to R.Z. (202004910423).The initial process by which novel sexual signals evolve remains unclear, because rare new variants are susceptible to loss by drift or counterselection imposed by prevailing female preferences.1,2,3,4 Here we describe diversification of an acoustic male courtship signal in Hawaiian populations of the field cricket Teleogryllus oceanicus, brought about by the evolution of a brachypterous wing morph (‘small-wing’) only six years ago.5 Small-wing has a genetic basis and causes silence or reduced-amplitude signalling by miniaturising male forewings, conferring protection against an eavesdropping parasitoid, Ormia ochracea.5 We found that wing reduction notably increases the fundamental frequency of courtship song from an average of 5.1 kHz to 6.4 kHz. It also de-canalizes male song, broadening the range of peak signal frequencies well outside normal song character space. As courtship song prompts female mounting and is sexually selected,6,7,8,9 we evaluated two scenarios to test the fate of these new signal values. Females might show reduced acceptance of small-wing males, imposing counter-selection via prevailing preferences. Alternatively, females might accept small-wing males as readily as long-wing males if their window of preference is sufficiently wide. Our results support the latter. Females preferred males who produced some signal over none, but they mounted sound-producing small-wing males as often as sound-producing long-wing males. Indiscriminate mating can facilitate persistence of rare, novel signal values. If female permissiveness is a general characteristic of the earliest stages of sexual signal evolution, then taxa with low female mate acceptance thresholds should be more prone to diversification via sexual selection.Peer reviewe
Current challenges and future prospects of osseointegration limb reconstruction for amputees
Get PDFAlthough osseointegration has proven successful at improving the physical deficits that traditional prostheses leave unfulfilled, future innovation should be systematically guided rather than randomly explored. Therefore, this article attempts to summarise, in a systematic manner, the challenges and prospects of osseointegration limb reconstruction for amputees from an implant design and manufacturing point of view, to provide a template for the development of the next generation of osseointegration implants. A scoping literature review was conducted, and key papers were identified and summarised. To combat osseointegration-related infection, advances such as smart implant coatings, mechanical inactivation of bacteria, biofilm eradication, implant monitoring technologies and nanotechnology were evaluated. Regarding production and biomaterials, the potential of 3D printing to balance supply and demand to achieve cost-effectiveness and sustainability were investigated. Considering the evolution of designs and the goal to provide a sensate limb, the prospects of smart implants, biofeedback and myoelectric pattern recognition were also explored. Osseointegration appears to follow a trajectory like that of total joint arthroplasty, which gained widespread clinical acceptance and adoption over the last 50 years. In our opinion, the future of amputee rehabilitation is bright, and we are optimistic osseointegration will continue to progress and advance as new technologies emerge.Peer reviewe
Four monuments and a funeral : established pathological mourning and collective memory in contemporary Hungary
No full textIn this chapter, I suggest that the rhetoric of the Hungarian far right largely resembles what Vamik Volkan has called Established Pathological Mourning. In such circumstances, mourning becomes extended, whereby an individual – or in the present case, a collective – cannot adaptively work through the loss of a loved object. Mourning rituals are extended, whereby the repetition of mourning is an attempt to ‘keep alive’ the lost object. Rather than being a recognition of loss, these complicated mourning rituals forestall the work of living on without the lost object. I suggest that, similar to the re-grief therapy that Volkan promotes, collective cultural mourning may offer an adaptive way forward in working through the issues of loss and control for a larger segment of a society
Exploring the advances of single-cell RNA sequencing in thyroid cancer : a narrative review
Get PDFThyroid cancer, a prevalent form of endocrine malignancy, has witnessed a substantial increase in occurrence in recent decades. To gain a comprehensive understanding of thyroid cancer at the single-cell level, this narrative review evaluates the applications of single-cell RNA sequencing (scRNA-seq) in thyroid cancer research. ScRNA-seq has revolutionised the identification and characterisation of distinct cell subpopulations, cell-to-cell communications, and receptor interactions, revealing unprecedented heterogeneity and shedding light on novel biomarkers for therapeutic discovery. These findings aid in the construction of predictive models on disease prognosis and therapeutic efficacy. Altogether, scRNA-seq has deepened our understanding of the tumour microenvironment immunologic insights, informing future studies in the development of effective personalised treatment for patients. Challenges and limitations of scRNA-seq, such as technical biases, financial barriers, and ethical concerns, are discussed. Advancements in computational methods, the advent of artificial intelligence (AI), machine learning (ML), and deep learning (DL), and the importance of single-cell data sharing and collaborative efforts are highlighted. Future directions of scRNA-seq in thyroid cancer research include investigating intra-tumoral heterogeneity, integrating with other omics technologies, exploring the non-coding RNA landscape, and studying rare subtypes. Overall, scRNA-seq has transformed thyroid cancer research and holds immense potential for advancing personalised therapies and improving patient outcomes. Efforts to make this technology more accessible and cost-effective will be crucial to ensuring its widespread utilisation in healthcare.Peer reviewe
Timing the evolution of phosphorus-cycling enzymes through geological time using phylogenomics
Get PDFPhosphorus plays a crucial role in controlling biological productivity, but geological estimates of phosphate concentrations in the Precambrian ocean, during life’s origin and early evolution, vary over several orders of magnitude. While reduced phosphorus species may have served as alternative substrates to phosphate, their bioavailability on the early Earth remains unknown. Here, we reconstruct the phylogenomic record of life on Earth and find that phosphate transporting genes (pnas) evolved in the Paleoarchean (ca. 3.6-3.2 Ga) and are consistent with phosphate concentrations above modern levels ( > 3 µM). The first gene optimized for low phosphate levels (pstS; <1 µM) appeared around the same time or in the Mesoarchean depending on the reconstruction method. Most enzymatic pathways for metabolising reduced phosphorus emerged and expanded across the tree of life later. This includes phosphonate-catabolising CP-lyases, phosphite-oxidising pathways and hypophosphite-oxidising pathways. CP-lyases are particularly abundant in dissolved phosphate concentrations below 0.1 µM. Our results thus indicate at least local regions of declining phosphate levels through the Archean, possibly linked to phosphate-scavenging Fe(III), which may have limited productivity. However, reduced phosphorus species did not become widely used until after the Paleoproterozoic Great Oxidation Event (2.3 Ga), possibly linked to expansion of the biosphere at that time.Peer reviewe
Enantioselective synthesis in continuous flow : polymer supported isothiourea-catalyzed enantioselective Michael addition-cyclization with α-azol-2-ylacetophenones
Get PDFEngineering and Physical Sciences Research Council - EP/W007517, EP/T023643/1A packed reactor bed incorporating a polymer-supported isothiourea HyperBTM catalyst derivative has been used to promote the enantioselective synthesis of a range of heterocyclic products derived from α-azol-2-ylacetophenones and -acetamides combined with alkyl, aryl, and heterocyclic α,β-unsaturated homoanhydrides in continuous flow via an α,β-unsaturated acyl-ammonium intermediate. The products are generated in good to excellent yields and generally in excellent enantiopurity (up to 97:3 er). Scale-up is demonstrated on a 15 mmol scale, giving the heterocyclic product in 68% overall yield with 98:2 er after recrystallization.Peer reviewe
Tax expenditures and progress to the Sustainable Development Goals
Get PDFAction Aid International Professor Sonia Buist Global Child Health Research Fund Scottish Funding CounciThis study reports the impact of governments having additional revenue equivalent to tax expenditures on achieving the Sustainable Development Goals in 97 countries. The study draws data on revenue foregone from the Global Tax Expenditure Database. To analyze the potential of an increase in government revenue equivalent to the revenue foregone, the study uses the Government Revenue and Development Estimations modeling. The study finds that if governments had additional revenue equivalent to tax expenditures: an additional 17 million children would attend school (13.62% currently out of school), an additional 70 million people would use basic water (23% of those without access), 146 million would use basic sanitation (20% of those without access), 181,000 children would survive (13% of children who currently die), and 12,000 mothers would survive (16% of mothers who currently die). Critically, there would be improvements in governance indicators in all regions. Foregone revenue from tax expenditures could increase access to public services for millions, which is the most effective tool for reducing inequality and driving progress toward sustainable development. The massive opportunity costs reported here require all governments to report and justify their annual tax expenditure.Peer reviewe
The ecological importance of oceanic islands for cetaceans : the case study of Madeira archipelago
No full textOpen ocean islands support resident cetaceans and are used seasonally as feeding/breeding areas by migrating populations. However, these usually small habitats are expected to have limited capacity to sustain many animals for long periods, especially in oligotrophic waters.
This study aimed at understanding how cetaceans use insular habitats, including their relevance to cetaceans’ survival and life cycles, and how cetacean species may share or compete for local marine resources. The study combined data from multiple survey types (2001 – 2017) to model the temporal and spatial use of Madeira archipelago waters by 10 cetacean species, including baleen whales, dolphins and deep divers, and to identify their local habitat preferences. Photo-identification, capture-mark-recapture methods and satellite telemetry were used to investigate the role of Madeira in the survival and life cycle of Bryde’s whales. Ecological niche partitioning among these cetacean species was studied using a multidisciplinary approach, where the trophic dimension was informed by stable isotopes and the spatial and temporal dimensions by habitat use models.
This study showed that open ocean islands are important for cetacean survival and play a role in many individuals’ life cycles; however, their relevance is dependent on the species energetic requirements and on the islands’ geographic context. Furthermore, the results suggest that Bryde’s whales are recent to Madeira, using it seasonally to feed and calve in the context of a wider Atlantic distribution, and added further evidence on their income breeder strategy. The study also found that the limited local resources are shared among species through ecological niche partitioning and differences in their degree of ecological specialisation, to minimize competitive exclusion. Nevertheless, some degree of competition may exist among a few species, which together with other factors, may shape their local habitat use, the trophic level at which they feed and their local seasonal succession
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