736 research outputs found
â13th Symposium of the International Work Group for Palaeoethnobotanyâ, Girona, Spain, 16th-22nd May 2004
The synthesis, photochemistry & electrochemistry of dithienylethene switches & their organometallic complexes
Chapter one presents a detailed literature survey on dithienylcyclopentene switches, describing their synthesis, properties and applications. The photochromic and electrochromic effects of functionalising such switching units with metal complexes, is then discussed. Finally, an introduction to cobalt carbonyl complexes is given, with
an outline of the photochemical and electrochemical properties of such carbonyl complexes, as described in the literature.
Chapter two describes the synthetic procedures employed to prepare a number of dithienyl-perhydro- and perfluoro-cyclopentene switches, substituted with thienyl and
ferrocenyl moieties. The methods used to generate their corresponding Co2(CO)6 and Co2(CO)4dppm complexes are also described. 1H, 13C, 19F and 31P NMR techniques
were employed to analyse the resulting products. Elemental analysis and infra-red spectroscopy were also utilised, where applicable, to further characterise the final pure
compounds and the results are detailed in this chapter.
Chapter three describes the photochemical properties found for the thienyl-based dithienylcyclopentene switches and their corresponding cobalt carbonyl complexes.
The photochromic properties of the thienyl-based switches were monitored in the UVvis absorption spectra and the 1H NMR spectra. Their thermal stability, fatigue
resistance and fluorescent properties were also investigated. Furthermore, the effects of incorporating cobalt carbonyl moieties onto these thienyl-based switches, on their photocyclisation processes, are reported in this chapter.
Chapter four reports the photochromic behaviour of the ferrocenyl-based dithienylcyclopentene switches, as observed in the UV-vis and 1H NMR. Investigations into the thermal stability, fatigue resistance and fluorescent properties of these switches were carried out. The effects on the photochromic properties of the ferrocenyl-based switches, following the introduction of Co2(CO)6 and
Co2(CO)4dppm moieties, are also described in this chapter.
Chapter five focuses on the electrochemical properties of the thienyl-based dithienylcyclopentene switches. Electrochemically induced cyclisation/
cycloreversion processes were investigated through cyclic voltammetry and UV-vis spectroelectrochemistry techniques. Similar experiments were carried out for the cobalt carbonyl derivatives in order to examine the effects of the presence of the metal carbonyls on the oxidative ring-closing/opening abilities of the thienyl-based switches.
The effects of the oxidation processes on the cobalt carbonyl centres were also studied by monitoring the changes of the carbonyl stretches in the infra-red spectra.
Chapter six details the electrochemical behaviour of the ferrocenyl-based dithienylcyclopentene switches. The oxidative and reductive processes of these
switches were monitored in the cyclic voltammograms and UV-vis spectra of these switches in order to investigate if ring-opening/closing can be induced by electrochemical means. Their Co2(CO)6 and Co2(CO)4dppm complexes were also
subjected to similar experiments in order to determine the effects of introducing such metal carbonyl complexes on the electrochemical switching behaviour of these
ferrocenyl-based switches. IR spectroelectrochemical techniques were employed to examine the effects of oxidation processes on the cobalt carbonyl centres.
Chapter seven presents an overall conclusion of the results obtained, with an emphasis on a comparison between the effects of the thiophene substituents and the ferrocene
units, and the prospects of future work in this area is discussed. All publications are presented in the appendix
Interview with Emma Coffield Dooley
An interview with Emma Dooley regarding her experiences in a one-room school house.https://scholars.fhsu.edu/ors/1132/thumbnail.jp
Practitioner perspectives of technology use in early years settings.
Perspectives of early years practitioners in English preschools were the focus for this thesis. Particularly exploring the use technology in the EYP role, and how they support children to use technology. Originally, intending to explore how the removal of technology and ICT from the 2021 revised Early Years Foundation Stage (EYFS) framework would affect provision, data was collected during the national lockdowns of COVID-19, so practitioners also shared experiences of how the use of technology and digital media changed during this time, and how childrenâs technology and digital media use in settings differed from pre lockdown.
To ensure data collection could continue during lockdowns, the original data collection method of focus groups changed to telephone interviews and online questionnaires that allowed 103 practitioners to share their views. However, despite a change in methods, a qualitative methodology remained.
Data suggests practitioners used digital media more during periods of lockdown, providing learning opportunities for children, meeting virtually with colleagues, and supporting parents. Childrenâs technology and digital media use in settings also changed; due to policy guidance, sanitising equipment and keeping children in âbubblesâ meant sharing devices became more difficult.
Practitioners shared opinions and beliefs that children use technology too much at home, without considering whether children use technology for consumption or creation in these spaces. Further, practitioners often use technology with children to âtick a boxâ for OFSTED without considering how these technologies can be woven into the classroom ecology to benefit all areas of learning and development as a tool for multimodal learning.
Recommendations for practice include working with qualification awarding organisations to ensure early years qualifications include some content on technology use, and the creation of a lead practitioner role (Digital Activity Lead Co-ordinator, or DALCo) who can champion and lead technology use in their setting
Renegotiating fatherâs identity following stillbirth: what and who am I?
This study examines the experiences of men following stillbirth in particular the challenges they face in claiming their identity as a father of an absent child. Fathers felt diminished when concerns about how they were coping were directed only to the women. Contrary to the notion that fatherâs experience suggests men suffer less distress, this research shows that men also deal with loss at an emotional level.
This investigation into menâs accounts of loss forms part of a larger study in which 28 men and women participated in interviews and focus groups about their experiences of perinatal death.
By listening to narrative accounts of loss, the passage to parenthood for bereaved men represents a disruption and re-evaluation of who they are, what they knew about the world as they negotiate the incomprehensibility of the death itself. Narratives by bereaved men also reveal how their sense of self and identity is mediated by the social and cultural milieu to which they belong and are largely disenfranchising experiences when friends, family and others, at times, fail to acknowledge the enormity of their loss.
The findings suggest that recognition of the death of baby who is stillborn as well as the impact of the death for fatherâs is intertwined with personal identity. Men in this study needed to receive recognition as fathers, both at the time of their loss and after. In examining the reproductive and bereavement journey of men, several domains occurred to illuminate the experience of men including; men as support partners; the impact of the death; parenting an absent child [advocate, protector]. The findings from this study will offer insight into the experiences of men that will resonate for others including practitioners who support individuals going through similar experiences.
Ethical approval for the study was granted by the University of Bristol Ethics Committee as part of doctoral research. Written informed consent was obtained by all study participants. No formal recruitment was obtained through the National Health Service or Government Institution and was entirely voluntary
RNA Sequencing Reveals Novel Transcripts from Sympathetic Stellate Ganglia During Cardiac Sympathetic Hyperactivity.
Cardiovascular disease is the most prevalent age-related illness worldwide, causing approximately 15 million deaths every year. Hypertension is central in determining cardiovascular risk and is a strong predictive indicator of morbidity and mortality; however, there remains an unmet clinical need for disease-modifying and prophylactic interventions. Enhanced sympathetic activity is a well-established contributor to the pathophysiology of hypertension, however the cellular and molecular changes that increase sympathetic neurotransmission are not known. The aim of this study was to identify key changes in the transcriptome in normotensive and spontaneously hypertensive rats. We validated 15 of our top-scoring genes using qRT-PCR, and network and enrichment analyses suggest that glutamatergic signalling plays a key role in modulating Ca2+ balance within these ganglia. Additionally, phosphodiesterase activity was found to be altered in stellates obtained from the hypertensive rat, suggesting that impaired cyclic nucleotide signalling may contribute to disturbed Ca2+ homeostasis and sympathetic hyperactivity in hypertension. We have also confirmed the presence of these transcripts in human donor stellate samples, suggesting that key genes coupled to neurotransmission are conserved. The data described here may provide novel targets for future interventions aimed at treating sympathetic hyperactivity associated with cardiovascular disease and other dysautonomias
Implant-Based Reconstruction following Mastectomy in Patients Who Have Had a Previous Breast Augmentation:Lessons from the National Multicenter Implant Breast Reconstruction Evaluation Study
Background: Breast augmentation is the most commonly performed cosmetic procedure, and increasingly women in this group present with breast cancer or request risk-reducing surgery, but their optimal management is unclear. The authors explored the clinical and patient-reported outcomes of patients undergoing immediate implant-based breast reconstruction following previous augmentation and compared these with outcomes of patients who had not had cosmetic implants in the Implant Breast Reconstruction Evaluation (iBRA) Study.  Methods: Patients undergoing immediate implant-based breast reconstruction were prospectively recruited from breast and plastic surgical units across the United Kingdom. Demographic, operative, and oncologic data, and information regarding complications within 3 postoperative months were collected. Patient-reported outcomes at 18 months were assessed using the BREAST-Q. The clinical and patient-reported outcomes of patients undergoing immediate implant-based breast reconstruction with and without previous breast augmentation were compared.  Results: A total of 2108 women were included in the iBRA Study, of whom 49 had undergone a previous augmentation. Women in the augmentation group were younger (median age, 45 years versus 50 years; p = 0.01), had a lower body mass index (22.8 kg/m2 versus 24.9 kg/m2; p < 0.01), and had smaller tumors (15 mm versus 25 mm; p = 0.01) than patients without augmentation. No differences were seen in operative technique between the groups. Complications at 3 months were similar in both groups and there were no significant differences in patient-reported outcomes at 18 months.  Conclusions: The clinical and patient-reported outcomes of patients undergoing immediate implant-based breast reconstruction following previous augmentation are consistent with those observed in the wider iBRA Study cohort, supporting the safety of this approach
Investigating the Impact of Unlimited Sucrose During Adolescence on Flex Maze Performance in Rats
As depression continues to impact many people, there are important considerations to be taken in how depression impacts people\u27s learning and motivations. The objective of this study is to examine the effects of unlimited sucrose consumption during adolescence, which can mimic symptoms of depression, on spatial memory and motivation in rats. The flex maze is used in the present study to assess these behaviors. Before initial training on the flex maze, 6 male rats were separated into two groups: an experimental group with unlimited access to 5% sucrose (and water) for approximately 3 weeks and a control group with free access to two bottles of plain water. Rats were first trained to complete the maze and during testing trials the time to complete the maze and the number of errors were recorded. Previous research has concluded that male rats fed a high-sucrose diet exhibited a delay in their ability to make decisions (Wong et al., 2017). Thus, we hypothesize that rats given unlimited access to sucrose water during adolescence would move slower in the flex maze due to the delay in making cognitive decisions because of depressive symptoms compared to control rats
A randomised trial of an internet weight control resource: The UK Weight Control Trial [ISRCTN58621669]
BACKGROUND:
Obesity treatment is notoriously unsuccessful and one of the barriers to successful weight loss reported by patients is a lack of social support. The Internet offers a novel and fast approach to the delivery of health information, enabling 24-hour access to help and advice. However, much of the health information available on the Internet is unregulated or not written by qualified health professionals to provide unbiased information. The proposed study aims to compare a web-based weight loss package with traditional dietary treatment of obesity in participants. The project aims to deliver high quality information to the patient and to evaluate the effectiveness of this information, both in terms of weight loss outcomes and cost-effectiveness.
METHODS:
This study is a randomised controlled trial of a weight loss package against usual care provided within General Practice (GP) surgeries in Leeds, UK. Participants will be recruited via posters placed in participating practices. A target recruitment figure of 220 will enable 180 people to be recruited (allowing for 22% dropout). Participants agreeing to take part in the study will be randomly allocated using minimisation to either the intervention group, receiving access to the Internet site, or the usual care group. The primary outcome of the study will be the ability of the package to promote change in BMI over 6 and 12 months compared with traditional treatment. Secondary outcomes will be the ability of the Internet package to promote change in reported lifestyle behaviours. Data will be collected on participant preferences, adherence to treatment, health care use and time off work. Difference in cost between groups in provision of the intervention and the cost of the primary outcome will also be estimated.
CONCLUSION:
A positive result from this study would enhance the repertoire of treatment approaches available for the management of obesity. A negative result would be used to inform the research agenda and contribute to redefining future strategies for tackling obesity
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