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A new genus of the family Spathiopterygidae (Hymenoptera: Diaprioidea) from mid-Cretaceous Kachin amber
Get PDFSpathiopterygid wasps represent an enigmatic group within Proctotrupomorpha, characterized by their minute size, their peculiar forewings with reduced venation and a pattern of microtrichiae, and highly reduced or absent hind wings. This family is known exclusively from Cretaceous ambers (ranging from the Barremian to the Santonian) and shows a wide geographic distribution. Specimens of this family are rare, and most of the species are only known from their holotypes, limiting our understanding of sexual dimorphism and intraspecific variability. Here, we describe Karaweik splendida Álvarez-Parra & Jouault gen. et sp. nov. from mid-Cretaceous Kachin amber, bringing the known paleodiversity of Spathiopterygidae to nine species distributed in seven genera. An updated species checklist and key are provided. We discuss the different nomenclatures for forewing venation used for the family and propose the term “pseudoveins” for what appear to be spectral veins, represented by rows of microtrichiae or membrane wrinkles. The studied specimen is anatomically compared with the other representatives of the family. We also address the potential belonging of Cretapria tsukadai Fujiyama, 1994, from Aptian Choshi amber in Japan, to Spathiopterygidae. The new species has tooth-like structures on the posteroventral part of the head, which may be related to a parasitoid behavior or wood-dwelling habit. Furthermore, we briefly comment on the paleobiology of the family and compare the possible flight modes of spathiopterygids with those of mymarids and mymarommatids
The third Asilidae (Diptera: Asiloidea) from mid-Cretaceous Kachin amber
No full textAsilidae, also known as assassin flies, are rare in Mesozoic deposits, with the highest diversity documented from mid-Cretaceous Kachin amber and the Aptian Crato Formation. To enhance our understanding of the past diversity of this group, we describe and illustrate a new genus and species, named Burmatriclis spinosus n. gen. n. sp. This new taxon has two rather infrequent characters, viz. absence of pulvilli and apices of the claws blunt, perhaps in relation to the capture of particular prey. With the addition of this new species, the diversity of the family Asilidae during the Cretaceous encompasses five species, and we anticipate the description of more species in the future
‘Machinery of femininity control’: The IOC, gendered medical policy, and patriarchal oppression of female athletes during the Cold War (1968-1992)
Get PDFThis dissertation meticulously explores the origins, historical trajectory, and implications of gender verification testing in the Olympic Games from 1968 to 1992. Employing an interdisciplinary approach that blends queer history with sports and medical narratives, it provides a nuanced understanding of the complex interplay of political, cultural, and scientific dynamics, with a primary focus on the policies of the International Olympic Committee (IOC). The research extensively utilises primary sources, mainly letters from the IOC Historical Archives, revealing the institutional biases and entrenched patriarchal structures that shaped these policies. The dissertation begins by examining the initial exclusion of women from the modern Olympics and their gradual, albeit limited, inclusion. It sets the stage for understanding the resistance to gender equality within sports institutions. It delves into the establishment and perpetuation of structural patriarchy within sports administration bodies such as the IOC and the International Amateur Athletic Federation (IAAF), shedding light on the barriers hindering women’s access to sports and recognition. The narrative unfolds further by exploring the discourse surrounding gender verification testing. It explores the socio-political dimensions, highlighting the Cold War-era fears of Eastern Bloc nations potentially fielding male athletes disguised as females, thus turning sports into a battleground for ideological assertion. Simultaneously, it scrutinises the introduction of mandatory testing, notably through the Barr Body test at the 1968 Mexico City Olympics, as a manifestation of shifting paradigms towards a policy intrinsically gendered, reinforcing rigid binary definitions of gender based on chromosomes. The study also examines the discourse surrounding testing, including critiques from influential women within sports administration, ultimately concluding that these policies inadvertently perpetuated gender discrimination, with ethical considerations often overshadowed by concerns for medical accuracy. Finally, the dissertation highlights the influence of societal pressures in shaping the critique, leading to the IOC’s eventual reassessment of gender verification policies at the meeting of the 1988 working group. In conclusion, this dissertation transcends the Cold War narrative of gender verification testing, presenting it as a manifestation of entrenched patriarchal values. By advocating for the recognition and addressing of these biases, it calls for transformative reforms towards genuine gender equality in sports
Jews, group libel, and free speech in the United Kingdom and United States, 1912-1969
Get PDFFor more than half the 20th century, American and British Jews wrestled with a too-little- remembered proposal called group libel – the idea that defamation law should guard the reputation not just of individuals but of groups like themselves. Through group libel, American and British Jews debated and negotiated their relationship to the state and the law, as well as the bounds of their own identity. The first full-length study of the issue in either the British or American case, this thesis takes a comparative approach, showing how British Jews related ambivalently to legal tactics while American Jews embraced the law in their respective battles against antisemitism and fascism. It aims to show that law was an imperfect instrument even for those groups most enthusiastic about its uses. Nevertheless, legal measures’ siren song called established Jews reluctant about more extreme action. Group libel proved the best of unenviable options for Jewish organizations like the Board of Deputies of British Jews, American Jewish Committee, and American Jewish Congress, who searched for new ways to fight against antisemites without disturbing the bounds of the established social order. Still, it proved too radical for the British and American governments. The thesis explores the history of ideas hotly debated today, such as the danger of antisemitism, the limits of free speech, and the utility (or lack thereof) of legal solutions to intergroup hatred. It aims to show the contours of these debates in an earlier time and to unearth their roots in doing so
Role of mammographic density and other risk factors in the development and detection of breast cancer
Get PDFMammographic density (MD) is the extent of radiologically dense breast tissue. It is an important risk factor for breast cancer and it reduces mammographic screening sensitivity. Menopausal hormone therapy (MHT) is known to reduce screening sensitivity due to its association with increased MD. The aim of this thesis was to elucidate the role of MD, alongside various other risk factors, in the development and detection of breast cancer. This was done through 1) a systematic review and meta-analysis of the association of breast cancer risk factors with MD; 2) a cross-sectional analysis of the association of breast cancer risk factors with MD in the Million Women Study (MWS), a UK-based screening cohort; 3) a prospective analysis of the effects of MHT, an important determinant of MD, on screening sensitivity in the MWS; and finally 4) developing overall breast cancer and subtype-specific (based on mode of detection and grade) risk prediction models using easily collectable risk factor information from questionnaires, and determining if given risk factors were better at predicting specific breast cancer subtypes, are were more likely to be missed at screening. The systematic review, with 59 studies, suggested that higher alcohol intake and later age at first birth and menarche were associated with higher MD, while parity and smoking were inversely associated with MD. These results were largely in agreement with the analysis of the MWS, with MD data on 8190 women, in which current/recent MHT use, older age at first birth, alcohol consumption, physical activity, and benign breast disease were positively associated with MD, whereas age, parity, smoking and BMI were inversely associated with MD. The prospective analysis of MHT use, with 27,564 breast cancer cases, found that screening sensitivity was reduced in current/recent MHT users and that although this impact on screening sensitivity declined after stopping MHT use, it remained elevated 10+ years post-cessation, likely due to some persistence in the effects of MHT use on MD. The overall and subtype-specific risk prediction models using easily collectable questionnaire data (not including MD) performed poorly. MHT was only marginally predictive of cancers diagnosed out of screening, and none of the other risk factors were notably better at predicting specific breast cancer subtypes. This thesis has confirmed and expanded upon existing knowledge regarding the role of MD and other breast cancer risk factors on breast cancer risk and detection at screening. Identifying those at greater risk of breast cancer or having their cancers missed at screening will ultimately guide future public education decisions, MHT prescribing practices, lifestyle advice, and – after further economic evaluation – possible personalised screening strategies
Stabilisation of HIF signalling in the mouse epicardium extends embryonic potential and neonatal heart regeneration
Get PDFIn humans, new-born infants can regenerate their heart during early life. This is modelled in the mouse, where regenerative capacity is maintained for the first week after birth but lost thereafter. Reactivation of this process holds great therapeutic potential; however, the molecular pathways that might be targeted to extend neonatal regeneration remain elusive. Here, we explored a role for hypoxia and HIF signalling on the regulation of epicardial activity in the developing mouse heart and in modulating the response to injury. Hypoxic regions were found in the epicardium from mid-gestation, associating with HIF-1α and HIF-2α, and expression of the epicardial master regulator Wilms’ tumour 1 (WT1). Epicardial deletion of Hif1α reduced WT1 levels, leading to impaired coronary vasculature. Targeting of the HIF degradation enzyme PHD, through pharmacological inhibition with a clinically approved drug or epicardial-specific genetic deletion of Egln1, stabilised HIF and promoted WT1 activity ex vivo. Finally, a combination of genetic and pharmacological stabilisation of HIF during neonatal heart injury led to prolonged epicardial activation, preservation of myocardium, augmented infarct resolution and preserved function beyond the 7-day regenerative window. These findings suggest modulation of HIF signalling extends epicardial activation to maintain myocardial survival beyond the neonatal regenerative window and may represent a viable strategy for treating ischaemic heart disease
Regarding: 'Determinants of decision-making in orthognathic surgery among patients in Ha'il region, Saudi Arabia'
Get PDFMitochondrial DNA Depletion Syndrome 1 ( MTDPS1 )—A Novel Cause of Premature Ovarian Insufficiency
Get PDFMitochondrial DNA depletion syndrome 1 (MTDPS1) is a rare autosomal recessive disorder caused by mutations in the TYMP gene, leading to mitochondrial failure. Hallmark features include gastrointestinal dysmotility, cachexia, peripheral neuropathy, ocular signs, hearing loss, and leukoencephalopathy. We present a 39‐year‐old woman with premature ovarian insufficiency (POI) as a novel endocrine manifestation of MTDPS1. She had normal pubertal development with menarche at age 10. In her mid‐20s, she developed fatigue, nausea, vomiting, abdominal pain, weight loss, and amenorrhoea at age 29. Investigations revealed POI with elevated FSH levels, a normal karyotype, negative autoimmune markers. Imaging showed a thin endometrium, small ovaries, osteoporosis, severe gastroparesis. An incidental renal angiomyolipoma prompted an MRI of the brain, revealing symmetrical abnormal white matter changes, suggestive of leukodystrophy. Given diagnostic uncertainty and a history of consanguinity she was referred to clinical genetics and underwent whole genome sequencing which identified a novel homozygous variant (c.559C > T; p.(Gln 187*)) in the TYMP gene, confirming MTDPS1. Though POI is not a well‐established feature of MTDPS1, mutations in other genes linked with mitochondrial function are known to be associated with POI and we postulate that this is an endocrine manifestation of MTDPS1. Genetic assessment should be considered in unexplained POI, particularly if associated with other clinical features/consanguinity
Analgesia through FKBP51 inhibition at disease onset confers lasting relief from sensory and emotional chronic pain symptoms
Get PDFChronic pain affects 20 to 30% of the population and imposes a significant socioeconomic burden as it is often accompanied by substantial emotional comorbidities such as anxiety and depression. Yet, the mechanisms underlying the interactions between the sensory and emotional aspects of chronic pain remain poorly understood. Here, we investigated the role of FKBP51, a regulator of the stress response, in mediating both sensory and emotional symptoms of chronic pain. Inhibition of FKBP51, via genetic deletion or pharmacological blockade, in persistent joint pain reduced fast-onset sensory, functional and activity-related symptoms, as well as late anxio-depressive comorbidities. FKBP51 inhibition after the establishment of the hypersensitive state provided only temporary symptoms relief, while acute inhibition at disease onset protected from the full development of sensory and anxio-depressive symptoms for up to 6 mo. Our results also indicated that early pain symptoms could predict the late sensory and emotional outcomes of chronic pain. RNA sequencing of spinal cord tissue revealed that late FKBP51 inhibition transiently altered nociceptive genes associated with mechanical hypersensitivity. In contrast, early inhibition persistently downregulated the Naaa gene, a key regulator of the transition to chronic pain, and reorganized spinal cilia. Our results indicate that early FKBP51 inhibition after injury can persistently reduce chronic pain and prevent the onset of associated emotional comorbidities by modulating critical spinal neurobiological pathways that play pivotal roles in the transition to chronic pain
The nature, structure, and perception of illumination
Get PDFIllumination is a defining characteristic of natural environments, yet its nature and spatial structure remain poorly understood. I argue first that illumination is not simply light: it is an emergent, ecologically significant kind. Illumination has features not possessed by light, and contains self-organizing structures that persist through the continual flow of light itself. These structures are immaterial and ephemeral, yet no less real for that. I then argue that these illumination entities are genuine objects of perception. This contrasts with the majority view, which explains illumination-dependent variations in appearance solely by appeal to the perceived properties of material objects. The argument exploits the proposed ontology, which shows that the structure of illumination is more like that of continuous masses of fluid than of discrete solids. Illumination entities are thus individuated not by rigid boundaries, but by stable patterns of intensity and flow. I argue that this fluid-like structure is mirrored by a distinctive type of perceptual organization, whereby scenes are parsed into zones and flows of illumination at multiple scales. This organization involves attributing spatial-structural features that apply distinctively to illumination, which warrants treating it as an object of perception