Prevention of headache after lumbar puncture: questionnaire survey of neurologists and neurosurgeons in United Kingdom

No abstract available

Expression of natural killer receptor alleles at different Ly49 loci occurs independently and is regulated by major histocompatibility complex class I molecules.

Ly49 receptor genes are expressed by subsets of natural killer (NK) cells in an overlapping fashion, accounting for the capacity of NK subsets to attack host cells that have selectively downregulated self-major histocompatibility complex (MHC) class I molecules. It was shown previously that most NK cells express only one or the other allele of a given Ly49 gene, while a smaller population expresses both alleles. However, the methods used to detect monoallelic and biallelic cells were nonquantitative. Here, new allele-specific antibodies were used to provide the first quantitative examination of biallelic and monoallelic expression of Ly49A and Ly49G2. The results demonstrate conclusively that most Ly49A(+) and Ly49G2(+) NK cells express the corresponding gene in a monoallelic fashion, with a smaller subset expressing both alleles. Unexpectedly, biallelic Ly49A(+) NK cells were more numerous than predicted by completely independent allelic expression, suggesting some heterogeneity among NK progenitors in the potential to express a given Ly49 gene. The data also show that cells expressing one allele of Ly49G2 may express Ly49A from the same or opposite chromosome with equal likelihood, indicating that the expressed allele is chosen independently for different Ly49 genes. Finally, the data demonstrate that biallelic expression of Ly49A or Ly49G2 occurs least frequently in mice that express ligands for these receptors (H-2(d) mice), and most frequently in class I-deficient mice. Thus, biallelic expression of Ly49 genes is regulated by interactions of NK cell progenitors with MHC class I molecules

Query Complexity of Derivative-Free Optimization

This paper provides lower bounds on the convergence rate of Derivative Free Optimization (DFO) with noisy function evaluations, exposing a fundamental and unavoidable gap between the performance of algorithms with access to gradients and those with access to only function evaluations. However, there are situations in which DFO is unavoidable, and for such situations we propose a new DFO algorithm that is proved to be near optimal for the class of strongly convex objective functions. A distinctive feature of the algorithm is that it uses only Boolean-valued function comparisons, rather than function evaluations. This makes the algorithm useful in an even wider range of applications, such as optimization based on paired comparisons from human subjects, for example. We also show that regardless of whether DFO is based on noisy function evaluations or Boolean-valued function comparisons, the convergence rate is the same

Caring for continence in stroke care settings: a qualitative study of patients’ and staff perspectives on the implementation of a new continence care intervention

Objectives: Investigate the perspectives of patients and nursing staff on the implementation of an augmented continence care intervention after stroke. Design: Qualitative data were elicited during semi-structured interviews with patients (n = 15) and staff (14 nurses; nine nursing assistants) and analysed using thematic analysis. Setting: Mixed acute and rehabilitation stroke ward. Participants: Stroke patients and nursing staff that experienced an enhanced continence care intervention. Results: Four themes emerged from patients’ interviews describing: (a) challenges communicating about continence (initiating conversations and information exchange); (b) mixed perceptions of continence care; (c) ambiguity of focus between mobility and continence issues; and (d) inconsistent involvement in continence care decision making. Patients’ perceptions reflected the severity of their urinary incontinence. Staff described changes in: (i) knowledge as a consequence of specialist training; (ii) continence interventions (including the development of nurse-led initiatives to reduce the incidence of unnecessary catheterisation among patients admitted to their ward); (iii) changes in attitude towards continence from containment approaches to continence rehabilitation; and (iv) the challenges of providing continence care within a stroke care context including limitations in access to continence care equipment or products, and institutional attitudes towards continence. Conclusion: Patients (particularly those with severe urinary incontinence) described challenges communicating about and involvement in continence care decisions. In contrast, nurses described improved continence knowledge, attitudes and confidence alongside a shift from containment to rehabilitative approaches. Contextual components including care from point of hospital admission, equipment accessibility and interdisciplinary approaches were perceived as important factors to enhancing continence care

Technology transfer potential of an automated water monitoring system

The nature and characteristics of the potential economic need (markets) for a highly integrated water quality monitoring system were investigated. The technological, institutional and marketing factors that would influence the transfer and adoption of an automated system were studied for application to public and private water supply, public and private wastewater treatment and environmental monitoring of rivers and lakes

Ion implanted Si:P double-dot with gate tuneable interdot coupling

We report on millikelvin charge sensing measurements of a silicon double-dot system fabricated by phosphorus ion implantation. An aluminum single-electron transistor (SET) is capacitively coupled to each of the implanted dots enabling the charging behavior of the double-dot system to be studied independently of current transport. Using an electrostatic gate, the interdot coupling can be tuned from weak to strong coupling. In the weak interdot coupling regime, the system exhibits well-defined double-dot charging behavior. By contrast, in the strong interdot coupling regime, the system behaves as a single-dot.Comment: 11 pages, 5 figure

Molecular-beam epitaxy of CrSi_2 on Si(111)

Chromium disilicide layers have been grown on Si(111) in a commercial molecular‐beam epitaxy machine. Thin layers (10 nm) exhibit two epitaxial relationships, which have been identified as CrSi_2(0001)//Si(111) with CrSi_2[1010]//Si[101], and CrSi_2(0001)//Si(111) with CrSi_2[1120]//Si[101]. The latter case represents a 30° rotation of the CrSi_2 layer about the Si surface normal relative to the former case. Thick (210 nm) layers were grown by four different techniques, and the best‐quality layer was obtained by codeposition of Cr and Si at an elevated temperature. These layers are not single crystal; the largest grains are observed in a layer grown at 825 °C and are 1–2 μm across

Challenges to optimal medicines use in people living with dementia and their caregivers: A literature review

Dementia is fast becoming a global concern due to a demographic shift towards an older population. Many studies have shown that caring for a family member or friend has a profound and negative impact on the physical, emotional and psychosocial aspects of the caregivers’ life. One significant activity that a family caregiver undertakes is assistance with the management of medicines. This review was undertaken to ascertain what the issues are that affect optimal medicines use from the perspectives of people living with dementia and their caregivers, both in the community and care home settings. A literature search was conducted using electronic databases, employing a combination of search terms. A total of 16 studies met the inclusion criteria. Six broad themes were identified, together with some recommendations to improve medicines use in people with dementia. Challenges to medicines use centred on medicines management and administration, the impact on the caregiver and care recipient, their partnership and interface with formal care. Future research should focus on developing targeted interventions that can overcome these challenges to achieve optimal medicines use