The application of chiral liquid crystal solvents to the NMR of polymers

In recent years there has been a significant amount of research into the uses of chiral liquid crystal polymers as solvents in solution state Nuclear Magnetic Resonance (NMR).The NMR spectra of molecules in liquid crystalline solvents can be markedly different to the spectra observed for the isotropic solution. In these anisotropic environments which are neither isotropic liquid phase or crystalline, some of the NMR parameters do not average to zero. Chemical shift anisotropy, dipolar couplings and quadrupolar interactions become a feature of the spectra and in certain circumstances can be measured. Dipolar couplings, if introduced to a spectrum, can make the results very complicated as there can be a great many interactions. Quadrupolar couplings are often larger than dipolar couplings and therefore easier to observe, however this is dependent on the nuclei under investigation having a spin > 1/2.In these studies, it was the observation of chemical shift anisotropy which was to be the aim of the investigation and in particular the hypothesis that the technique could be used for enantiomeric purity determination. It is assumed that the R and S species will be oriented slightly differently in the solvent and so produce slightly different spectra. Once the method of sample preparation had been perfected the aim was to apply this technique to the elucidation of the stereochemistry of polymer samples. The purpose being to establish a protocol to assign polymer tacticity without the need for isotopic substitution, such as deuterium labelling

Serum tumor necrosis factor-alpha concentrations are negatively correlated with serum 25(OH)D concentrations in healthy women

<p>Abstract</p> <p>Background</p> <p>Circulating 25 hydroxyvitamin D (25 (OH)D), an accurate measure of vitamin D status, is markedly greater in individuals with increased exposure to ultraviolet B (UVB) light via sunlight or the use of artificial UV light. Aside from the known relationship between vitamin D and bone, vitamin D has also been implicated in immune function and inflammation. Furthermore, a mass of evidence is accumulating that vitamin D deficiency could lead to immune malfunction. Our overall objective was to study the relationship between vitamin D status (as determined by serum 25(OH) D concentrations) and inflammatory markers in healthy women.</p> <p>Methods</p> <p>This observational study included 69 healthy women, age 25–82 years. Women with high UVB exposure and women with minimal UVB exposure were specifically recruited to obtain a wide-range of serum 25(OH)D concentrations. Health, sun exposure and habitual dietary intake information were obtained from all subjects. Body composition was determined by dual-energy-x-ray absorptiometry. A fasting blood sample was collected in the morning and analyzed for serum 25(OH)D, parathyroid hormone (iPTH), estradiol (E₂), cortisol, and inflammatory markers [tumor necrosis factor -alpha (TNF-α), interleukin-6 and -10 (IL-6, IL-10), and C-reactive protein (CRP)].</p> <p>Results</p> <p>Women with regular UVB exposure (Hi-D) had serum 25(OH)D concentrations that were significantly higher (<it>p </it>< 0.0001) and iPTH concentrations that were significantly lower (<it>p </it>< 0.0001) than women without regular UVB exposure (Lo-D). Although IL-6, IL-10, and CRP did not have a statistically significant relationship with 25(OH)D concentrations, linear regression models revealed a significant inverse relationship between serum 25(OH)D and TNF-α concentrations. This relationship remained significant after controlling for potential covariates such as body fat mass, menopausal status, age, or hormonal contraceptive use.</p> <p>Conclusion</p> <p>Serum 25(OH)D status is inversely related to TNF-α concentrations in healthy women, which may in part explain this vitamin's role in the prevention and treatment of inflammatory diseases. Results gleaned from this investigation also support the need to re-examine the biological basis for determining optimal vitamin D status.</p

A Qualitative Study of Public Perspectives on Family Support Services in Ireland

t Family Support Services (FSS) were set up to help families to cope with the stress and strain of modern life. Such services have been considered to be of immense value to people living in designated disadvantaged areas. However, there is little information on the public\u27s perception of family support services in Ireland. Since the provision of efficient and effective services requires knowledge of users\u27 needs, it is essential that these issues be addressed. The purpose of this study therefore is to investigate parents\u27 views and experiences of family support services by a qualitative exploratory study conducted in the North West Sector of Cork City in the late 20th century. This area was selected as it is one of the most socially disadvantaged areas in Ireland. The study consisted of in-depth interviews with 10 mothers and a focus group with another to mothers. Such as small scale study was undertaken as there was a distinct lack of evidence on users\u27 views on Irish FSS to warrant a larger sample. Analysis of mothers\u27 accounts suggested that use of FSS was affected by the perceived stigmatising effect of using the services, disillusionment at the quality of the service provision, the invasion of domestic privacy and lack of users\u27 input into the services being provided. There was also a lack of knowledge amongst the respondents about the services and it emerged that more effective advertising about the available FSS in the area was needed. Family Support Services are targeted at families coping with normal parenting stresses but can also be effective when working with vulnerable families who are affected by domestic violence, child abuse, racism, prejudice and mental health difficu lties. As a result, FSS have much to offer the public but the absence of studies on users\u27 perspectives needs to be addressed if efficient and effective service provision is to be provided. Little has been published since the study was conducted and given the importance placed on FSS, it is crucial that some research be done in the near future

Delivering routine immunisations in London during the COVID-19 pandemic: lessons for future vaccine delivery. A mixed-methods study.

BACKGROUND: General practices in England have continued to care for patients throughout the COVID-19 pandemic by instigating major changes to service delivery. Immunisations have continued, although the number of vaccines delivered initially dropped in April 2020. AIM: To evaluate how COVID-19 impacted the delivery of immunisations in London and identify innovative practices to inform future delivery, including for COVID-19 vaccines. DESIGN & SETTING: A mixed-methods study of immunisation delivery in London, UK. METHOD: An online survey of London general practices was undertaken in May 2020 to produce a descriptive analysis of childhood immunisation delivery and identify innovative delivery models. Semi-structured interviews were conducted between August and November 2020 to explore innovative immunisation models, which were analysed thematically. RESULTS: Sixty-eight per cent (n = 830) of London practices completed the survey and 97% reported having continued childhood immunisation delivery. Common delivery adaptations included spaced-out appointments, calling parents beforehand, and having only one parent attend. Forty-three practices were identified as having innovative models, such as delivering immunisations outside practice buildings or offering drive-through services. The thematic analysis of 14 semi-structured interviews found that, alongside adaptations to immunisation delivery within practices, existing local networks collaborated to establish new immunisation delivery models. Local population characteristics affected delivery and provide insights for large-scale vaccine deployment. CONCLUSION: Immunisations continued during 2020 with practices adapting existing services. New delivery models were developed by building on existing local knowledge, experiences, and networks. Immunisation delivery during the pandemic, including for COVID-19 vaccines, should be tailored to local population needs by building on primary care immunisation expertise

Is partnership the answer? Delivering the national immunisation programme in the new English health system: a mixed methods study.

BACKGROUND: The English national health system experienced a major reorganisation in April 2013. This mixed methods study examined how staff managed to deliver the national immunisation programme within a new health infrastructure and explored the role and contribution of 'partnership working' to programme implementation. METHODS: A cross-sectional online questionnaire survey and a qualitative evaluation of an urban immunisation board were conducted in 2016. The questionnaire included 38 questions about immunisation responsibilities, collaboration, service evaluation and programme support. It was completed by 199 immunisation providers and 70 people involved in the management of the immunisation programme. The evaluation involved 12 semi-structured interviews, 3 observations of forum meetings and the review of forum meeting minutes. Descriptive statistical analysis of the survey data was performed using SPSS version 23 and qualitative data from both study components were uploaded to NVivo 11 and analysed thematically. RESULTS: Screening and Immunisation Teams were cited as responsible for programme leadership by 56% of survey respondents, but concerns were raised about their capacity to oversee larger geographies and a case made for decentralised accountability mechanisms. Only 44% of immunisation managers stated that poor performance was addressed adequately, and half of respondents thought that support given to providers was inadequate. Managers reported that partnership working improved the organisation (83%) and performance (78%) of immunisation, but stated it was more beneficial for information-sharing than implementation. A preference for a "locality working approach" with committees covering smaller health economies rather than larger commissioning areas was voiced. The immunisation board examined in the qualitative evaluation sought to achieve this by forging links with locally based steering committees, but also had to address internal challenges related to the role of the board and contribution of members to programmatic decision-making. CONCLUSIONS: Key challenges in delivering the immunisation programme were rooted in the new health infrastructure, which had created greater distance between commissioners and providers and resulted in the fragmentation of programme responsibilities. Partnership working bridged gaps but more needs to be done to strengthen accountability mechanisms and ensure that collaborative activities are outcome oriented and sustainable in the shifting environment of reorganisation

Purcell-Enhanced Single Photons at Telecom Wavelengths from a Quantum Dot in a Photonic Crystal Cavity

Quantum dots are promising candidates for telecom single photon sources due to their tunable emission across the different low-loss telecommunications bands, making them compatible with existing fiber networks. Their suitability for integration into photonic structures allows for enhanced brightness through the Purcell effect, supporting efficient quantum communication technologies. Our work focuses on InAs/InP QDs created via droplet epitaxy MOVPE to operate within the telecoms C-band. We observe a short radiative lifetime of 340 ps, arising from a Purcell factor of 5, owing to interaction of the QD within a low-mode-volume photonic crystal cavity. Through in-situ control of the sample temperature, we show both temperature tuning of the QD's emission wavelength and a preserved single photon emission purity at temperatures up to 25K. These findings suggest the viability of QD-based, cryogen-free, C-band single photon sources, supporting applicability in quantum communication technologies

Preliminary results of Galileo direct imaging of S-L 9 impacts

Direct Galileo imaging data were obtained of the Jupiter impact sites for Comet Shoemaker-Levy 9 fragments K, N, and W during their early, high-energy phases. Initial ∼5s-long flashes for all 3 impacts result from radiant bolides; analogous, abrupt onsets of luminosity observed by the Galileo photopolarimeter for other impacts must also be the bolide phase. The 3 bolides were dim at 0.56 or 0.89µm (few percent of total Jupiter) and had similar amplitudes, despite huge late-stage differences observed from Earth. Subsequent, continuous luminosity lasting ∼40s for K and ∼10s for N is optical radiation as the initial bolide train erupts into a “fireball”. The K light curve may show (a) two impacts 10s apart or (b) delayed evolution of the fireball