317 research outputs found
High-Altitude Emission from Pulsar Slot Gaps: The Crab Pulsar
We present results of a 3D model of optical to gamma-ray emission from the
slot gap accelerator of a rotation-powered pulsar. Primary electrons
accelerating to high-altitudes in the unscreened electric field of the slot gap
reach radiation-reaction limited Lorentz factors of 2 x 10^7, while
electron-positron pairs from lower-altitude cascades flow along field lines
interior to the slot gap. The curvature, synchrotron and inverse Compton
radiation of both primary electrons and pairs produce a broad spectrum of
emission from infra-red to GeV energies. Both primaries and pairs undergo
cyclotron resonant absorption of radio photons, allowing them to maintain
significant pitch angles. Synchrotron radiation from pairs with a power-law
energy spectrum with Lorentz factors 10^2 - 10^5, dominate the spectrum up to
10 MeV. Synchrotron and curvature radiation of primaries dominates from 10 MeV
up to a few GeV. We examine the energy-dependent pulse profiles and
phase-resolved spectra for parameters of the Crab pulsar as a function of
magnetic inclination and viewing angle, comparing to broad-band data. In most
cases, the pulse profiles are dominated by caustics on trailing field lines. We
also explore the relation of the high-energy and the radio profiles, as well as
the possibility of caustic formation in the radio cone emission. We find that
the Crab pulsar profiles and spectrum can be reasonably well reproduced by a
model with viewing angle 45 degrees and inclination angle 100 or 80 degrees.
This model predicts that the slot gap emission below 200 MeV will exhibit
correlations in time and phase with the radio emission.Comment: 35 pages, 7 figures, accepted for publication in Astrophysical
Journa
An iron(ii) spin-crossover metallacycle from a back-to-back bis-[dipyrazolylpyridine]
The syntheses of 4-mercapto-2,6-di(pyrazol-1-yl)pyridine (bppSH) and bis[2,6-di(pyrazol-1-yl)pyrid-4-yl]disulfide (bppSSbpp) are reported. In contrast to previously published “back-to-back” bis-[2,6-di(pyrazol-1-yl)pyridine] derivatives, which form coordination polymers with transition ions that are usually insoluble, bppSSbpp yields soluble oligomeric complexes with iron(II) and zinc(II). Mass spectrometry and DOSY data show that [{Fe(μ-bppSSbpp)}n]2n+ and [{Zn(μ-bppSSbpp)}n]2n+ form tetranuclear metallacycles in nitromethane solution (n = 4), although 1H NMR and conductivity measurements imply the iron compound may undergo more fragmentation than its zinc congener. Both [{Fe(bppSH)2]2+ and [{Fe(μ-bppSSbpp)}n]2n+ exhibit thermal spin-crossover in CD3NO2 solution, with midpoint temperatures near 245 K. The similarity of these equilibria implies there is little cooperativity between the iron centres in the metallacyclic structures
Home versus day rehabilitation: a randomised controlled trial
Objective: to assess the effect of home versus day rehabilitation on patient outcomes
Revised recommendations on standards and norms for palliative care in Europe from the European Association for Palliative Care (EAPC):A Delphi study
Background: In 2009, the EAPC published recommendations on standards and norms for palliative care in Europe, and a decade later, wished to update them to reflect contemporary practice. Aim: To elicit consensus on standards and norms for palliative care in Europe, taking account of developments since 2009. Design: A Delphi technique used three sequential online survey rounds, and a final expert consultation (EAPC Board). The original 2009 questionnaire with 134 statements was updated with 13 new concepts and practices following a scoping of the literature between 2009 and 2020 (total: 147 statements). Setting/participants: One contact of Boards of 52 national European organisations affiliated to the EAPC were invited to participate, with subsequent rounds sent to respondees. The EAPC Board (n = 13) approved final recommendations. Results: In Round 1: 30 organisations (14 organisations × two people, 16 organisations × one person, total n = 44) in 27 countries responded (response rate 58% organisations, 82% countries), Round 2 (n = 40), Round 3 (n = 38). 119 statements reached consensus in Round 1, 9 in Round 2, 7 in Round 3. In total 135/145 statements in five domains (terminology, philosophy, levels, delivery, services) reached consensus (defined as >75% agreement), (122) were original EAPC recommendations with 13 new recommendations included emerging specialisms: neonatal, geriatric and dementia care, and better care practices. Seven statements failed to reach consensus and four were removed as irrelevant or repetition. Conclusions: Most recommendations on standards and norms for palliative care in Europe remain unchanged since 2009. Evolving concepts in palliative care can be used to support advocacy
Developing and evaluating online COVID-centric advance care planning training and information resources for nursing staff and family members in nursing homes:The necessary discussions study protocol
Background: Nursing home residents are typically older adults with high levels of chronic illness and impairment. As such, they are particularly susceptible to severe complications and mortality from COVID-19. Since all nursing home residents are at increased risk, nursing home care staff need to know what residents would want to happen should they become infected with COVID-19. This study aims to develop and evaluate advance care planning (ACP) COVID-centric online training and information resources for nursing home staff and family members of residents, to improve care at the end of life during a COVID-19 outbreak. Based on the findings we will develop implementation guidelines for nursing homes to ensure wider impact and application during the pandemic and beyond. Methods: The content of the training and information resources will be based on a rapid review of literature and guidance on ACP in the context of COVID-19 and consultation with the study expert reference group. An integrated communications company will then work alongside the research team to design the online training and information resources. To evaluate the resources, we will employ a multiple case study design where a nursing home (defined as an institutional setting in which nursing care is provided to older adults on-site 24 hours a day) will be the unit of analysis or ‘case’. The RE-AIM (reach, effectiveness, adoption, implementation, maintenance) framework will guide the evaluation of implementation of the training and information resources. We will recruit and interview staff and family members from between 6-9 nursing homes across Northern Ireland, England and Scotland and gather quantitative data from a feedback survey included in the training and information resources. Discussion: The Necessary Discussions study is very timely given the challenging experiences of nursing homes, their staff, residents and their family members during the COVID-19 pandemic. It meets a key need and addresses an important gap in research and practice. The training and information resources will be ‘COVID-centric’, but they will also have a longstanding relevance for future ACP practice in UK care home
Do people with dementia and carers get what they need? : Barriers in social care and carers needs assessments
Background People with dementia and unpaid carers need to go through a social care or carers needs assessment to access and receive subsidised or fully-funded social care. With no previous evidence, this qualitative study aimed to provide insights into the access to, experiences of receiving and conducting social care or carers needs assessments, and access to social care. Methods Unpaid carers of people with dementia and professionals conducting social care or carers needs assessment living or working in England were interviewed remotely about their experiences between April and August 2023. Topic guides were co-produced with two unpaid carers, and both were supported to code anonymised transcripts. Thematic analysis was used to analyse the data. Findings Twenty-seven unpaid carers (n = 21) and professionals (n = 6) participated. Four themes were generated: (1) Issues with accessing needs assessments, not the process; (2) Knowledge of needs assessments and the health and social care system; (3) Expectations of unpaid carers; and (4) Post-assessment unmet needs. The most prominent barriers unpaid carers and their relatives with dementia encountered were awareness of and access to needs assessment. Unpaid carers were mostly unaware of the existence and entitlement to a needs assessment, and sometimes realised they had participated in one without their knowledge. Professionals described the pressures on their time and the lack of financial resources within services. Conclusions To facilitate improved access to dementia care and support for carers, the pathway to accessing needs assessments needs to be clearer, with better integration and communication between health and social care
Do people with dementia and carers get what they need? Barriers in social care and carers needs assessments.
BackgroundPeople with dementia and unpaid carers need to go through a social care or carers needs assessment to access and receive subsidised or fully-funded social care. With no previous evidence, this qualitative study aimed to provide insights into the access to, experiences of receiving and conducting social care or carers needs assessments, and access to social care.MethodsUnpaid carers of people with dementia and professionals conducting social care or carers needs assessment living or working in England were interviewed remotely about their experiences between April and August 2023. Topic guides were co-produced with two unpaid carers, and both were supported to code anonymised transcripts. Thematic analysis was used to analyse the data.FindingsTwenty-seven unpaid carers (n = 21) and professionals (n = 6) participated. Four themes were generated: (1) Issues with accessing needs assessments, not the process; (2) Knowledge of needs assessments and the health and social care system; (3) Expectations of unpaid carers; and (4) Post-assessment unmet needs. The most prominent barriers unpaid carers and their relatives with dementia encountered were awareness of and access to needs assessment. Unpaid carers were mostly unaware of the existence and entitlement to a needs assessment, and sometimes realised they had participated in one without their knowledge. Professionals described the pressures on their time and the lack of financial resources within services.ConclusionsTo facilitate improved access to dementia care and support for carers, the pathway to accessing needs assessments needs to be clearer, with better integration and communication between health and social care
Regulated Ire1-dependent decay of messenger RNAs in mammalian cells
Maintenance of endoplasmic reticulum (ER) function is achieved in part through Ire1 (inositol-requiring enzyme 1), a transmembrane protein activated by protein misfolding in the ER. The cytoplasmic nuclease domain of Ire1 cleaves the messenger RNA (mRNA) encoding XBP-1 (X-box–binding protein 1), enabling splicing and production of this active transcription factor. We recently showed that Ire1 activation independently induces the rapid turnover of mRNAs encoding membrane and secreted proteins in Drosophila melanogaster cells through a pathway we call regulated Ire1-dependent decay (RIDD). In this study, we show that mouse fibroblasts expressing wild-type Ire1 but not an Ire1 variant lacking nuclease activity also degrade mRNAs in response to ER stress. Using a second variant of Ire1 that is activated by a small adenosine triphosphate analogue, we show that although XBP-1 splicing can be artificially induced in the absence of ER stress, RIDD appears to require both Ire1 activity and ER stress. Our data suggest that cells use a multitiered mechanism by which different conditions in the ER lead to distinct outputs from Ire1
Sequence Variation in Multidrug-Ressitant Plasmid pLUH01, Isolated from Human Nasopharyngeal Swabs
Three variants of the multidrug-resistant plasmid pLUH01 were assembled by deep sequencing from nasopharyngeal swabs. All have a 21-bp deletion in the RS14515 hypothetical gene. Variants 1 through 3 have 2, 6, and 3 nucleotide substitutions, respectively, compared to the pLUH01 reference genome. We named the new plasmid variants pLUH01/Lancaster/2015/1 to pLUH01/Lancaster/2015/3
Genome sequence of human papillomavirus type 20, strain HPV-20/Lancaster/2015
The genome sequence of human papillomavirus type 20 (HPV-20; family Papillomaviridae, genus Betapapillomavirus, species Betapapillomavirus 1, type 20) was assembled by deep sequencing from nasopharyngeal swabs. The assembled genome is 0.37% divergent over its full length from the single complete genome of HPV-20 in GenBank (U31778). We named the strain HPV-20/Lancaster/2015
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