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Endothelial Protein Changes Indicative of Endometriosis in Unexplained Infertility, an Exploratory Study
Get PDFPrevious research has linked both endothelial protein changes and vitamin D with infertility. This study was undertaken to investigate the association of proteins associated with endothelial function and vitamin D status in the luteal phase at day 21 in a group of non-obese women prior to in vitro fertilization (IVF) with either unexplained infertility (UI) or male factor infertility (MFI). Twenty-five non-obese Caucasian women from a UK academic center with MFI (n = 14) and UI (n = 11) were recruited. Blood was withdrawn at day 21 of the menstrual cycle at the time of mock embryo transfer. Vitamin D parameters were measured by tandem mass spectroscopy. Off-rate Modified Aptamer (SOMA)-scan plasma protein measurement was undertaken for 20 protein markers of endothelial dysfunction. Baseline demographics did not differ between groups and parameters of response following IVF did not differ. Vitamins D2 and D3, and 1,25 Vitamin D3 did not differ between groups. In UI, markers of endothelial activation/dysfunction were investigated; vascular cell adhesion molecule 1 (VCAM-1) decreased and this is associated with endothelial stress; vascular endothelial growth factor (VEGF) decreased and this may suggest impaired endometrial angiogenesis; while intercellular adhesion molecule 1 (ICAM-3) increased (p < 0.05) and is associated with increased immunological activity. A marker of vascular integrity, angiopoietin-1, increased while soluble angiopoietin-1 receptor (sTie-2) decreased (p < 0.05), suggesting increased vascular development. Endothelial markers of inflammation, coagulation, and endothelial progenitor cells were unchanged. Vitamin D and its metabolites show no relationship to UI, but endothelial activation/dysfunction and vascular integrity changes in VCAM-1, VEGF, sICAM-3, angiopoietin-1, and sTie-2 may contribute to UI, though the mechanisms through which they work require further evaluation; however, these protein changes have been associated with endometriosis, raising the suggestion that subclinical/undiagnosed endometriosis may have contributed to UI in these subjects
Air quality forecasting and rating based on machine learning algorithm and cumulative logit model: an empirical study for Lanzhou city of China
Get PDFWith the quick development of society and industry, air quality has become a grim and global environmental concern. Predicting and rating air quality for many cities remains a significant challenge. Consequently, machine learning algorithms have garnered considerable attention for their potential to address these issues effectively. In this paper, firstly, based on daily air quality data from July 1, 2022 to June 30, 2023 in Lanzhou city of China, five machine learning models, including Bayes Model Averaging (BMA), Support Vector Machine (SVM), Gradient Boosting Decision Tree (GBDT), Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) are developed to predict the Air Quality Index (AQI) via six major air pollutants (PM2.5, PM10, SO2, NO2, O3 and CO). Secondly, we integrate Bootstrap algorithm into the optimal model, leading to the proposal of the LSTM-Bootstrap algorithm for deriving the standard errors and confidence intervals of the predicted AQI. Thirdly, a cumulative logit model is employed to evaluate and forecast AQI rating. The analysis results indicate that AQI rating is significantly affected by PM10, CO and O3. Additionally, to validate the efficacy of the suggested methods, a similar analysis is conducted on air quality data from Chengdu city for the same period. The findings provide valuable insights for future environmental policies and air quality management strategies
The impact of home institutions on the internationalization of emerging market SMEs: a systematic review
Get PDFPurpose: The purpose of this paper is to review literature on home-country institutional factors influencing the internationalization of small and medium-sized enterprises (SMEs) from emerging markets. Based on the analysis, the authors propose a research agenda to guide future studies in this field. Design/methodology/approach: This paper follows a systematic procedure to review 58 selected articles on how institutional contexts in emerging economies impact SME internationalization, covering studies from 1999 to 2023. This period was chosen to capture recent research following the post-1990 market liberalization in most emerging economies, which has shaped new opportunities and challenges for SMEs expanding abroad. Findings: This literature review shows that SMEs’ internationalization knowledge in emerging markets is strongly shaped by home-country institutional conditions. Key mechanisms include imprinting by home institutions and learning from domestic institutional sources, both critical yet underexplored areas in SME development. These processes offer substantial opportunities for future research into how institutional contexts influence SMEs’ global growth. Originality/value: This research builds on previous studies that have emphasized firm-level and external factors such as host market appeal, consumer needs and resource availability driving SMEs’ internationalization. Focusing on home institutional factors, the authors provide a comprehensive review of academic studies and propose a future research agenda on the external institutional influences shaping emerging market SMEs’ global expansion
The Magnet Effect of Price Limits: An Agent-Based Approach
No full textIn this paper, we study the magnet effect within the context of circuit breaker events that transpired in global stock markets during March 2020. Our analysis encompasses nine such events across six countries. Employing a time-distanced quadratic function to model trading activities leading up to limit hits, we observe a substantial acceleration in return movement and the convergence of traders’ behavior preceding limit hits. Furthermore, most circuit breaker events manifest a distinct reduction in trading volume and amplified market stability during this crucial phase. To gain deeper insights into the magnet effect, we employ an agent-based model of the stock market that incorporates price limits. Our model replicates the stylized facts associated with limit hit events and the magnet effect. Importantly, our simulation results closely align with empirical observations. We also emphasize the importance of market environment changes and shifts in traders’ behavior in influencing limit hit events and the magnet effect
The genome sequence of the dace, Leuciscus leuciscus (Linnaeus, 1758) (Cypriniformes: Leuciscidae)
No full textWe present a genome assembly from an individual Leuciscus leuciscus (Dace; Chordata; Actinopteri; Cypriniformes; Leuciscidae). The assembly contains two haplotypes with total lengths of 1 198.36 megabases and 1 179.02 megabases. In haplotype 1, 96.76% of the sequence is scaffolded into 25 chromosomal pseudomolecules, and 97.75% of the haplotype 2 sequence is similarly scaffolded. The mitochondrial genome has also been assembled, with a length of 17.59 kilobases. This assembly was generated as part of the Darwin Tree of Life project, which produces reference genomes for eukaryotic species found in Britain and Ireland
North of England Alcohol Team (NEAT) research partnership: barriers and opportunities to deliver research into alcohol related liver disease in the north of England
No full textBackgroundAlcohol-related liver disease is a common cause of premature death, with higher incidence in the north of England and particularly in areas of high deprivation. Despite this burden of disease, research into liver disease has historically been delivered in other areas of the United Kingdom. THe North of England Alcohol Team (NEAT) research partnership was funded by the NIHR to improve the infrastructure for research into ArLD and in the north of england.MethodsNEAT used a variety of methods to bring together stakeholders in ArLD to face-to-face and virtual meetings to identify current barriers to research, possible solutions and research priorities in ArLD. A dedicated public and patient involvement and engagement (PPIE) group was established to support NEAT and future research. An online educational resource was developed. Finally, online workshops including all relevant stakeholders delivered applications for further research funding for specific projects.ResultsNEAT used a variety of workstreams to achieve its aims. Regional meetings allowed face to face discussion as well as online conversations to identify current barriers to research in ArLD and potential measures to overcome them. Research priorities were confirmed and means to address research barriers were discussed. A PPIE group was convened, and terms of engagement agreed. A virtual research training pack was developed. Research questions were developed, discussed and prepared for future funding applications. We plan to investigate the value of community clinics to improve engagement with liver medicine.ConclusionsNEAT brought together a wide range of stakeholders with an interest in improving access to research for people living with alcohol related liver injury. Infrastructure for research was developed including training resources and a PPIE group. This will underpin future research into ArLD in the north of England and more widely
Surviving in the Margins: Understanding Children’s Perceptions and Experiences of Child Criminal Exploitation and County Lines
No full textThis thesis explores perceptions and lived experiences of criminally exploited children aged 9-18. Using semi-structured in-depth interviews, the study deepens understanding of children’s victimisation within the framework of county lines exploitation, adopting a trauma-informed and public health lens to uncover the causes of the causes that lead to increased vulnerability.Findings reveal that children are coerced into criminal activities within county lines networks at very young ages. Even at 9 years-old, these experiences are daily occurrences, more ad hoc and opportunistic than the organised and prolonged grooming typically presented in intervention strategies and awareness campaigns. This generates a cohort of younger “invisible victims” seldom heard, and seldom safeguarded. Children’s accounts portray environments underscored by exposure to violence, weapons and drugs, leading to a "learned apathy" toward danger and an ambivalence regarding safety. This results in a skewed sense of acceptable risk – ‘is it safe enough?’. Externalised as bravado, such behaviours mask children’s visceral fear, and reflect deeply rooted survival responses formed from multiple Adverse Childhood Experiences and trauma. Serving as a barrier to victim-identification, this is misinterpreted as voluntary recklessness and complicity in criminality rather than an attempt to reclaim control and power by children existing on the periphery of society whose agency is repeatedly denied. This prevents children receiving vital protection, instead leading to criminalisation and intensified victimisation.This study concludes with a new application of “fawning”: a survival response by children to “please, appease and pacify” county line exploiters, not just for safety but to ascertain a sense of belonging, security, autonomy, and status thus creating trauma-coerced bonds. Children’s marginalisation and socioeconomic strain culminates in a fatalistic worldview - with school exclusion representing a pivotal moment that entrenches negative self-perceptions and sense of hopelessness. This demonstrates the cyclical nature and complex dynamics of marginalisation, vulnerability and victimisation presented in this study
Imperialism after decolonization? British relations with Bahrain from the withdrawal East of Suez to the Iranian Revolution
Get PDFThere is a growing consensus that the end of empire did not necessarily equate with a severing of imperial ties. Some historians have even argued that there was a shift from formal to informal empire in Britain’s relations with the emerging Gulf States. This is especially so with respect to Bahrain which had represented the epicentre of Britain’s position in the Gulf. Nevertheless, an analysis of British relations with Bahrain from the withdrawal East of Suez to the Iranian Revolution belies any notion that Britain succeeded in establishing an informal imperial position after 1971. Not only were Britain’s economic interests in Bahrain eroded by growing competition from its industrial rivals, but also its political and military position was challenged by the encroachment of regional powers. Any hope that Britain could retain an imperial role in Bahrain was undermined still further by the emergence of new internal political forces in Bahrain beyond the direct control of either the ruling family or Britain itself. The unfeasibility of maintaining an imperial relationship with Bahrain after 1971 persuaded British policymakers to seek to establish recognizably post-imperial relations with the Emirate in the decade following the withdrawal from East of Suez