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Climate & speciation in the Mediterranean: a focus on Narcissus L.
No full textChanges in climatic conditions are important drivers of plant speciation initiating
diversification, speciation, and extinction. The disruption of climate in recent decades that
comes under the umbrella of climate change is affecting the current relationships between
current plant distributions and climates, which is introducing new threats to biodiversity at a
level not previously seen during human civilization. Narcissus has a centre of diversity in the
Iberian Peninsula, a region with a complex climatic and geological history. Previous
estimates of Narcissus divergence in the Miocene differ by 7.6 million years. Using next-generation sequencing, plastome (163 whole plastomes and a subset of 78 protein-coding
genes from this) and low-copy nuclear (261 Angiosperms353 genes for 101 taxa),
phylogenetic trees and networks were built to decipher the impact of past changes in climate
on Narcissus diversification and distributional patterns, including the role of hybridisation
across the genus. The dated plastome phylogeny of Amaryllidaceae indicated the Eurasian
clade diverged 18.26 MYA (95% 12.22 – 24.75 MYA) and the Narcissus phylogeny indicated
it diverged 13.64 MYA (95% HPD = 9.00 – 18.50 MYA) during the Miocene in the Iberian
Peninsula. Climatic and geological events may have initiated allopatric and hybrid speciation
across the genus and determined current distributions. High levels of cytonuclear
discordance between plastome and nuclear phylogenies were recovered, which was
attributed to hybridisation and introgression. Explicit phylogenetic networks confirmed the
ancient hybrid origin of sections such as Dubii and Nevadensis, which occurred following
climate-induced range shifts. Ancient hybridisation detected here, also explains
discrepancies between morphological and molecular taxonomic treatments such as section
Bulbocodii. The evolutionary relationships recovered by these phylogenetic analyses will
contribute towards a taxonomic revision of Narcissus. Overall, this thesis demonstrates the
significant role of climatic changes on Narcissus evolution, which initiated climate-induced
diversification and speciation, with repeated range shifts initiating hybrid speciation
Worker productivity during Covid-19 and adaptation to working from home
Get PDFWe examine workers’ reported productivity, which we validate against external metrics, over the course of the Covid-19 pandemic. On average, workers report being at least as productive as before the pandemic’s onset. However, this average masks substantial heterogeneity, which is linked to job quality, gender, the presence of children, and ease of working from home. As the pandemic progressed, those who previously performed well at home were more likely to remain there. Building on these findings, we estimate factors affecting productivity outcomes across locations controlling for endogenous selection. We find that those in ‘good’ jobs (with managerial duties and working for large firms) were advantaged specifically in the home environment. More generally we find an effect of key personality traits – agreeableness and conscientiousness – on productivity outcomes across locations
Entrapment and defeat scales: factor structure assessment and variation by gender and sexual identity among adults in the United Kingdom
No full textEntrapment and defeat are empirically-supported suicide risk factors. Their measurement is the subject of some debate, however. Also, limited work exists examining sexual and gender minority (SGM) differences in these suicide risk factors despite overall elevated rates of suicidal thoughts and behaviors (STBs) for SGM persons. The present study examined (1) entrapment and defeat differences by sexual orientation and gender identity, (2) factor structure and criterion validity of the Entrapment Scale (E-Scale) and the Defeat Scale (D-Scale), and (3) measurement invariance by sexual orientation (subsamples were too small for gender identity). A sample of 1,027 adults living in the United Kingdom completed a cross-sectional online questionnaire assessing mental health. Analysis of Variance and Kruskal-Wallis testing revealed: (1) all sexual minority (i.e., gay/lesbian, bisexual, and other SM) persons reported higher internal and external entrapment, defeat, and suicidal ideation compared to their heterosexual counterparts, and; (2) gender minority (i.e., transgender and gender diverse) persons reported higher internal and external entrapment, defeat, and suicidal ideation compared to cisgender persons. Supported by suicide theory, confirmatory factor analysis showed modest support for a two-factor E-Scale (internal and external), and a one-factor D-Scale. All entrapment and defeat scores displayed significant moderate positive correlations with suicidal ideation. E- and D-scale scores displayed high intercorrelation, tempering confidence in conclusions regarding the facture structure findings. Item threshold-level responding varied by sexual orientation for the D-Scale but not the E-Scale. Results are discussed with respect to suicide theory and measurement, public health, and clinical practice
Geoarchaeology in a peri-urban environment: a soil micromorphological case study of the “Land of Aynadamar" in Nasrid Granada, the northern outskirts of the last Islamic town in Iberia (13th-16th c.)
No full textGranada (Spain) was the capital of the Nasrid Kingdom, the last Islamic emirate in Iberian Peninsula during the 13th-15th centuries. Th e Land of Aynadamar is located on a hillside north of the city of Granada, on the third hill in the urban complex. Th e hill to the south is occupied by the Alhambra, the palatine city where the Nasrid sultans resided. Th e Land of Aynadamar can be considered as part of the ‘castlescape’ of the Alhambra and its study contextualises further this iconic monument, even though the Alhambra was a palatine citadel and not only a single castle. Th is research, which applies soil micromorphological analysis in conjunction with the historical sources, excavation data, and palaeoenvironmental data, demonstrates how the suburban land- scape was transformed following the Castilian conquest and the Christian colonisation in the last peri-urban place of al-Andalus. Archaeological soil and sediment micromorphological analysis has identifi ed nuances in the stratigraphic sequences from four separate areas comprising agricultural terraces, peri-urban farmsteads, and a palatine residence, and it has identifi ed periods of abandonment or the disuse of areas that are maybe contemporaneous. Th ese periods of abandonment relate to an important transition in the occupation of the Land of Aynadamar that marks the decline of Nasrid rule and changes associated with the Christian conquest from the 16th century onwards
Region-specific changes in brain glutamate and gamma-aminobutyric acid across the migraine attack in children and adolescents
No full textIn patients with migraine, an excitation–inhibition imbalance that fluctuates relative to attack onset has been proposed to contribute to the underlying pathophysiology of migraine, but this has yet to be explored in children and adolescents. This prospective, observational, cohort study examined glutamate and gamma-aminobutyric acid (GABA) levels across the phases of a migraine attack and interictally in children and adolescents using magnetic resonance spectroscopy. Macromolecule-suppressed GABA (sensorimotor cortex and thalamus) and glutamate (occipital cortex, sensorimotor cortex, and thalamus) were measured in children and adolescents (10-17 years) with a migraine diagnosis with or without aura 4 times over 2 weeks. Linear mixed-effects models examined changes in glutamate and GABA during the 72 hours leading up to, and after the onset of an attack. We found significant region-specific changes in glutamate and GABA. Specifically, sensorimotor GABA significantly increased leading up to the headache phase, whereas glutamate significantly decreased following the headache onset in the occipital cortex and the thalamus. Post hoc analyses examined the 24 hours leading up to or following the onset of the headache phase. In the 24 hours before the headache onset, sensorimotor glutamate, occipital glutamate, and thalamic GABA decreased. In the 24 hours post headache onset, sensorimotor glutamate continued to decrease. Our results suggest changes in glutamate and GABA that are consistent with the thalamocortical dysrhythmia hypothesis. These findings provide insight into developmental migraine pathophysiology and may open future avenues for treatment targets specific to children and adolescents
Enhancing constructivist learning: the role of generative AI in personalised learning experiences
Get PDFThis paper explores the transformative role of generative AI in enhancing constructivist learning, where students actively construct knowledge through meaningful experiences. By investigating the synergies between generative AI and constructivist learning, the study uncovers how AI fosters personalized educational experiences. The research underscores the profound influence of generative AI on constructivist learning, empowering students to become active, motivated, and lifelong learners by tailoring their education, fostering creativity and collaboration, and upholding ethical principles. The study advocates for the responsible and purposeful integration of generative AI, which would revolutionize education and prepare students for future challenges
Transforming autistic children and young people's school experiences through difficult conversations between educators
Get PDFThe majority of identified autistic children in the English state school system are educated in mainstream settings. However, many autistic children and young people in such settings have difficult school experiences and impoverished educational outcomes. Historically, the debate around how to improve outcomes for this group of pupils has centred on identifying ways in which autistic learners can better adapt to the school environment rather than considering the ways in which teachers, educators, and policymakers might adapt their assumptions, beliefs, and practices. In this chapter, I review some of the key literature and employ a combination of relevant theory and my own empirical research with autistic young people to make the case for why difficult conversations between staff in schools are necessary to urgently address the stigma and prejudice which surrounds neurodivergent pupils
Himawari-8 sea surface temperature products from the Australian Bureau of Meteorology
Get PDFAs a contribution to the Integrated Marine Observing System (IMOS), the Bureau of Meteorology introduces new reprocessed Himawari-8 satellite-derived Sea Surface Temperature (SST) products. The Radiative Transfer Model and a Bayesian cloud clearing method is used to retrieve SSTs every 10 min from the geostationary satellite Himawari-8. An empirical Sensor Specific Error Statistics (SSES) model, introduced herein, is applied to calculate bias and standard deviation for the retrieved SSTs. The SST retrieval and compositing method, along with validation results, are discussed. The monthly statistics for comparisons of Himawari-8 Level 2 Product (L2P) skin SST against in situ SST quality monitoring (iQuam) in situ SST datasets, adjusted for thermal stratification, showed a mean bias of −0.2/−0.1 K and a standard deviation of 0.4–0.7 K for daytime/night-time after bias correction, where satellite zenith angles were less than 60◦ and the quality level was greater than 2. For ease of use, these native resolution SST data have been composited using a method introduced herein that retains retrieved measurements, to hourly, 4-hourly and daily SST products, and projected onto the rectangular IMOS 0.02 degree grid. On average, 4-hourly products cover ≈10% more of the IMOS domain, while one-night composites cover ≈25% more of the IMOS domain than a typical 1 h composite. All available Himawari-8 data have been reprocessed for the September 2015–December 2022 period. The 10 min temporal resolution of the newly developed Himawari-8 SST data enables a daily composite with enhanced spatial coverage, effectively filling in SST gaps caused by transient clouds occlusion. Anticipated benefits of the new Himawari-8 products include enhanced data quality for applications like IMOS OceanCurrent and investigations into marine thermal stress, marine heatwaves, and ocean upwelling in near-coastal regions
Presenting a long-term, reprocessed dataset of global sea surface temperature produced using the OSTIA system
Get PDFOver the past few decades, the oceans have stored the majority of the excess heat in the climate system resulting from anthropogenic emissions. An accurate, long-term sea surface temperature (SST) dataset is essential for monitoring and researching the changes to the global oceans. A variety of SST datasets have been produced by various institutes over the years, and here, we present a new SST data record produced originally within the Copernicus Marine Environment Monitoring Service (which is therefore named CMEMS v2.0) and assess: (1) its accuracy compared to independent observations; (2) how it compares with the previous version (named CMEMS v1.2); and (3) its performance during two major volcanic eruptions. By comparing both versions of the CMEMS datasets using independent in situ observations, we show that both datasets are within the target accuracy of 0.1 K, but that CMEMS v2.0 is closer to the ground truth. The uncertainty fields generated by the two analyses were also compared, and CMEMS v2.0 was found to provide a more accurate estimate of its own uncertainties. Frequency and vector analysis of the SST fields determined that CMEMS v2.0 feature resolution and horizontal gradients were also superior, indicating that it resolved oceanic features with greater clarity. The behavior of the two analyses during two volcanic eruption events (Mt. Pinatubo and El Chichón) was examined. A comparison with the HadSST4 gridded in situ dataset suggested a cool bias in the CMEMS v2.0 dataset versus the v1.2 dataset following the Pinatubo eruption, although a comparison with sparser buoy-only observations yielded less clear results. No clear impact of the El Chichón eruption (which was a smaller event than Mt. Pinatubo) on CMEMS v2.0 was found. Overall, with the exception of a few specific and extreme events early in the time series, CMEMS v2.0 possesses high accuracy, resolution, and stability and is recommended to users
