1,463 research outputs found
Vertical shift register using dipolar interaction in magnetic multilayers
A vertical shift register consisting of multi-layered ferromagnetic bars with in-plane magnetization is investigated numerically using macrospin simulations. These layers are anti-ferromagnetically coupled via dipolar interactions and their in-plane aspect ratio determines their anisotropy. A single data bit is represented by a magnetic kink soliton, which forms at the boundary of two anti-parallel domains with opposite phases. It can be propagated bi-directionally using an externally applied rotating magnetic field. The soliton propagation is dependent on the applied field strength, the magnetic anisotropy of the ferromagnetic layers, and the dipolar coupling energies. For the device investigated here, the largest field range for soliton propagation is found to be from 35 Oe to 235 Oe at a lateral aspect ratio of 1.33. The soliton is also subjected to edge effects where it can be either pinned or reflected rather than being expelled from the stack. It is found that by reducing the thickness of the edge layer, these effects can be reduced substantially. By reducing the thickness of the edge layer by 20%, the field range in which the soliton is expelled increases by more than a factor of two.This project has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 309589 (M3d), as well as the Seventh Framework Programme ERC Contract No. 247368 (3SPIN). AFP acknowledges funding from an EPSRC Early Career Fellowship, EP/M008517/1 and from the Winton Foundation.This is the author accepted manuscript. The final version is available from AIP via http://dx.doi.org/10.1063/1.493791
Increased entropy of signal transduction in the cancer metastasis phenotype
Studies into the statistical properties of biological networks have led to
important biological insights, such as the presence of hubs and hierarchical
modularity. There is also a growing interest in studying the statistical
properties of networks in the context of cancer genomics. However, relatively
little is known as to what network features differ between the cancer and
normal cell physiologies, or between different cancer cell phenotypes. Based on
the observation that frequent genomic alterations underlie a more aggressive
cancer phenotype, we asked if such an effect could be detectable as an increase
in the randomness of local gene expression patterns. Using a breast cancer gene
expression data set and a model network of protein interactions we derive
constrained weighted networks defined by a stochastic information flux matrix
reflecting expression correlations between interacting proteins. Based on this
stochastic matrix we propose and compute an entropy measure that quantifies the
degree of randomness in the local pattern of information flux around single
genes. By comparing the local entropies in the non-metastatic versus metastatic
breast cancer networks, we here show that breast cancers that metastasize are
characterised by a small yet significant increase in the degree of randomness
of local expression patterns. We validate this result in three additional
breast cancer expression data sets and demonstrate that local entropy better
characterises the metastatic phenotype than other non-entropy based measures.
We show that increases in entropy can be used to identify genes and signalling
pathways implicated in breast cancer metastasis. Further exploration of such
integrated cancer expression and protein interaction networks will therefore be
a fruitful endeavour.Comment: 5 figures, 2 Supplementary Figures and Table
The association of health literacy with adherence in older 2 adults, and its role in interventions: a systematic meta-review
Background: Low health literacy is a common problem among older adults. It is often suggested to be associated with poor adherence. This suggested association implies a need for effective adherence interventions in low health literate people. However, previous reviews show mixed results on the association between low health literacy and poor adherence. A systematic meta-review of systematic reviews was conducted to study the association between health literacy and adherence in adults above the age of 50. Evidence for the effectiveness of adherence interventions among adults in this older age group with low health literacy was also explored. Methods: Eight electronic databases (MEDLINE, ERIC, EMBASE, PsycINFO, CINAHL, DARE, the Cochrane Library, and Web of Knowledge) were searched using a variety of keywords regarding health literacy and adherence. Additionally, references of identified articles were checked. Systematic reviews were included if they assessed the association between health literacy and adherence or evaluated the effectiveness of interventions to improve adherence in adults with low health literacy. The AMSTAR tool was used to assess the quality of the included reviews. The selection procedure, data-extraction, and quality assessment were performed by two independent reviewers. Seventeen reviews were selected for inclusion. Results: Reviews varied widely in quality. Both reviews of high and low quality found only weak or mixed associations between health literacy and adherence among older adults. Reviews report on seven studies that assess the effectiveness of adherence interventions among low health literate older adults. The results suggest that some adherence interventions are effective for this group. The interventions described in the reviews focused mainly on education and on lowering the health literacy demands of adherence instructions. No conclusions could be drawn about which type of intervention could be most beneficial for this population. Conclusions: Evidence on the association between health literacy and adherence in older adults is relatively weak. Adherence interventions are potentially effective for the vulnerable population of older adults with low levels of health literacy, but the evidence on this topic is limited. Further research is needed on the association between health literacy and general health behavior, and on the effectiveness of interventions
Chair based exercise in community settings: a cluster randomised feasibility study
Background: Some older people who find standard exercise programmes too strenuous may be encouraged to exercise while remaining seated - chair based exercises (CBE). We previously developed a consensus CBE programme (CCBE) following a modified Delphi process. We firstly needed to test the feasibility and acceptability of this treatment approach and explore how best to evaluate it before undertaking a definitive trial.
Methods: A feasibility study with a cluster randomised controlled trial component was undertaken to 1. Examine the acceptability, feasibility and tolerability of the intervention and 2. Assess the feasibility of running a trial across 12 community settings (4 day centres, 4 care homes, 4 community groups). Centres were randomised to either CCBE, group reminiscence or usual care. Outcomes were collected to assess the feasibility of the trial parameters: level of recruitment interest and eligibility, randomisation, adverse events, retention, completion of health outcomes, missing data and delivery of the CCBE. Semi- structured interviews were conducted with participants and care staff following the intervention to explore acceptability.
Results: 48% (89 out of 184 contacted) of eligible centres were interested in participating with 12 recruited purposively. 73% (94) of the 128 older people screened consented to take part with 83 older people then randomised following mobility testing. Recruitment required greater staffing levels and resources due to 49% of participants requiring a consultee declaration. There was a high dropout rate (40%) primarily due to participants no longer attending the centres. The CCBE intervention was delivered once a week in day centres and community groups and twice a week in care homes. Older people and care staff found the CCBE intervention largely acceptable.
Conclusion: There was a good level of interest from centres and older people and the CCBE intervention was largely welcomed. The trial design and governance procedures would need to be revised to maximise recruitment and retention. If the motivation for a future trial is physical health then this study has identified that further work to develop the CCBE delivery model is warranted to ensure it can be delivered at a frequency to elicit physiological change. If the motivation for a future trial is psychological outcomes then this study has identified that the current delivery model is feasible
How functional programming mattered
In 1989 when functional programming was still considered a niche topic, Hughes wrote a visionary paper arguing convincingly ‘why functional programming matters’. More than two decades have passed. Has functional programming really mattered? Our answer is a resounding ‘Yes!’. Functional programming is now at the forefront of a new generation of programming technologies, and enjoying increasing popularity and influence. In this paper, we review the impact of functional programming, focusing on how it has changed the way we may construct programs, the way we may verify programs, and fundamentally the way we may think about programs
Allele-specific miRNA-binding analysis identifies candidate target genes for breast cancer risk
Most breast cancer (BC) risk-associated single-nucleotide polymorphisms (raSNPs) identified in genome-wide association studies (GWAS) are believed to cis-regulate the expression of genes. We hypothesise that cis-regulatory variants contributing to disease risk may be affecting microRNA (miRNA) genes and/or miRNA binding. To test this, we adapted two miRNA-binding prediction algorithms-TargetScan and miRanda-to perform allele-specific queries, and integrated differential allelic expression (DAE) and expression quantitative trait loci (eQTL) data, to query 150 genome-wide significant ( P≤5×10-8 ) raSNPs, plus proxies. We found that no raSNP mapped to a miRNA gene, suggesting that altered miRNA targeting is an unlikely mechanism involved in BC risk. Also, 11.5% (6 out of 52) raSNPs located in 3'-untranslated regions of putative miRNA target genes were predicted to alter miRNA::mRNA (messenger RNA) pair binding stability in five candidate target genes. Of these, we propose RNF115, at locus 1q21.1, as a strong novel target gene associated with BC risk, and reinforce the role of miRNA-mediated cis-regulation at locus 19p13.11. We believe that integrating allele-specific querying in miRNA-binding prediction, and data supporting cis-regulation of expression, improves the identification of candidate target genes in BC risk, as well as in other common cancers and complex diseases.Funding Agency
Portuguese Foundation for Science and Technology
CRESC ALGARVE 2020
European Union (EU)
303745
Maratona da Saude Award
DL 57/2016/CP1361/CT0042
SFRH/BPD/99502/2014
CBMR-UID/BIM/04773/2013
POCI-01-0145-FEDER-022184info:eu-repo/semantics/publishedVersio
Unmet needs of patients with chronic obstructive pulmonary disease (COPD): A qualitative study on patients and doctors
Background: Chronic Obstructive Pulmonary Disease (COPD) is a chronic disease with repeated exacerbations resulting in gradual debilitation. The quality of life has been shown to be poor in patients with COPD despite efforts to improve self-management. However, the evidence on the benefit of self-management in COPD is conflicting. Whether this could be due to other unmet needs of patients have not been investigated. Therefore, we aimed to explore unmet needs of patients from both patients and doctors managing COPD.
Methods: We conducted a qualitative study with doctors and patients in Malaysia. We used convenience sampling to recruit patients until data saturation. Eighteen patients and eighteen doctors consented and were interviewed using a semi-structured interview guide. The interviews were audio-recorded, transcribed verbatim and checked by the interviewers. Data were analysed using a thematic approach.
Results: The themes were similar for both the patients and doctors. Three main themes emerged: knowledge and awareness of COPD, psychosocial and physical impact of COPD and the utility of self-management. Knowledge about COPD was generally poor. Patients were not familiar with the term chronic obstructive pulmonary disease or COPD. The word ‘asthma’ was used synonymously with COPD by both patients and doctors. Most patients experienced difficulties in their psychosocial and physical functions such as breathlessness, fear and helplessness. Most patients were not confident in self-managing their illness and prefer a more passive role with doctors directing their care.
Conclusions: In conclusion, our study showed that knowledge of COPD is generally poor. There was mislabelling of COPD as asthma by both patients and physicians. This could have resulted in the lack of understanding of treatment options, outcomes, and prognosis of COPD. The misconception that cough due to COPD was contagious, and breathlessness that resulted from COPD, had important physical and psychosocial impact, and could lead to social isolation. Most patients and physicians did not favour self-management approaches, suggesting innovations based on self-management may be of limited benefit
Senescence and tumour clearance is triggered by p53 restoration in murine liver carcinomas
Although cancer arises from a combination of mutations in oncogenes and tumour suppressor genes, the extent to which tumour suppressor gene loss is required for maintaining established tumours is poorly understood. p53 is an important tumour suppressor that acts to restrict proliferation in response to DNA damage or deregulation of mitogenic oncogenes, by leading to the induction of various cell cycle checkpoints, apoptosis or cellular senescence(1,2). Consequently, p53 mutations increase cell proliferation and survival, and in some settings promote genomic instability and resistance to certain chemotherapies(3). To determine the consequences of reactivating the p53 pathway in tumours, we used RNA interference (RNAi) to conditionally regulate endogenous p53 expression in a mosaic mouse model of liver carcinoma(4,5). We show that even brief reactivation of endogenous p53 in p53-deficient tumours can produce complete tumour regressions. The primary response to p53 was not apoptosis, but instead involved the induction of a cellular senescence program that was associated with differentiation and the upregulation of inflammatory cytokines. This program, although producing only cell cycle arrest in vitro, also triggered an innate immune response that targeted the tumour cells in vivo, thereby contributing to tumour clearance. Our study indicates that p53 loss can be required for the maintenance of aggressive carcinomas, and illustrates how the cellular senescence program can act together with the innate immune system to potently limit tumour growth
The Complete Genome Sequence of Escherichia coli EC958: A High Quality Reference Sequence for the Globally Disseminated Multidrug Resistant E. coli O25b:H4-ST131 Clone
Escherichia coli ST131 is now recognised as a leading contributor to urinary tract and bloodstream infections in both community and clinical settings. Here we present the complete, annotated genome of E. coli EC958, which was isolated from the urine of a patient presenting with a urinary tract infection in the Northwest region of England and represents the most well characterised ST131 strain. Sequencing was carried out using the Pacific Biosciences platform, which provided sufficient depth and read-length to produce a complete genome without the need for other technologies. The discovery of spurious contigs within the assembly that correspond to site-specific inversions in the tail fibre regions of prophages demonstrates the potential for this technology to reveal dynamic evolutionary mechanisms. E. coli EC958 belongs to the major subgroup of ST131 strains that produce the CTX-M-15 extended spectrum β-lactamase, are fluoroquinolone resistant and encode the fimH30 type 1 fimbrial adhesin. This subgroup includes the Indian strain NA114 and the North American strain JJ1886. A comparison of the genomes of EC958, JJ1886 and NA114 revealed that differences in the arrangement of genomic islands, prophages and other repetitive elements in the NA114 genome are not biologically relevant and are due to misassembly. The availability of a high quality uropathogenic E. coli ST131 genome provides a reference for understanding this multidrug resistant pathogen and will facilitate novel functional, comparative and clinical studies of the E. coli ST131 clonal lineage
Reversal of aberrant cancer methylome and transcriptome upon direct reprogramming of lung cancer cells
10.1038/srep00592Scientific Reports2
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