290 research outputs found
Resonant-tunnelling-assisted crossing for subwavelength plasmonic slot waveguides
We theoretically investigate the properties of crossing for two perpendicular
subwavelength plasmonic slot waveguides. We show that, when encountering nano
intersection, the crosstalk for the direct crossing is around 25%, almost same
as throughout. In terms of symmetry considerations and resonant-tunnelling
effect, we design compact cavity-based structures. Our results show that the
crosstalk is eliminated and the throughput reaches the unity on resonance.
Simulations results are in agreement with those from the coupled-model theory.
When taking into account of the material loss, due to the unchanged symmetry
properties of the modes, the crosstalk is still suppressed. Our results may
open a way to construct nanoscale crossings for high-density nanoplasmonic
integration circuits
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Factors affecting dairy farmers' attitudes towards antimicrobial medicine usage in cattle in England and Wales
There has been growing concern about bacterial resistance to antimicrobials in the farmed livestock sector. Attention has turned to sub-optimal use of antimicrobials as a driver of resistance. Recent reviews have identified a lack of data on the pattern of antimicrobial use as an impediment to the design of measures to tackle this growing problem. This paper reports on a study that explored use of antibiotics by dairy farmers and factors influencing their decision-making around this usage.
We found that respondents had either recently reduced their use of antibiotics, or planned to do so. Advice from their veterinarian was instrumental in this. Over 70% thought reducing antibiotic usage would be a good thing to do. The most influential source of information used was their own veterinarian. Some 50% were unaware of the available guidelines on use in cattle production. However, 97% thought it important to keep treatment records.
The Theory of Planned Behaviour was used to identify dairy farmers’ drivers and barriers to reduce use of antibiotics. Intention to reduce usage was weakly correlated with current and past practice of antibiotic use, whilst the strongest driver was respondents’ belief that their social and advisory network would approve of them doing this. The higher the proportion of income from milk production and the greater the chance of remaining in milk production, the significantly higher the likelihood of farmers exhibiting positive intention to reduce antibiotic usage. Such farmers may be more commercially minded than others and thus more cost-conscious or, perhaps, more aware of possible future restrictions.
Strong correlation was found between farmers’ perception of their social referents’ beliefs and farmers’ intent to reduce antibiotic use. Policy makers should target these social referents, especially veterinarians, with information on the benefits from, and the means to, achieving reductions in antibiotic usage. Information on sub-optimal use of antibiotics as a driver of resistance in dairy herds and in humans along with advice on best farm practice to minimise risk of disease and ensure animal welfare, complemented with data on potential cost savings from reduced antibiotic use would help improve poor practice
A global study to identify a potential basis for policy options when integrating animal welfare into the UN Sustainable Development Goals
A previously developed methodology to rate the strength of the impact of improving animal welfare on achieving each of the 17 SDGs and the impact of achieving each SDG on animal welfare was used at the third Animal Welfare Global Forum of the World Organisation for Animal Health. Data from 95 participants from key stakeholder categories and organisations involved in animal welfare were analysed. The resulting ‘map’ of the relative strengths of these associations confirmed the expected co-benefits of improving animal welfare and achieving the SDGs. Differences at regional level and according to the economic classification of the country were also identified. This paper focuses on using this ‘map’ as a potential guide for how organisations interested in improving animal welfare could identify potential new allies for strategic partnerships to facilitate the implementation of different policy options. For example, a strategy can be to collaborate with those organisations where the impact is of similar mutual benefit, e.g. between improving animal welfare and achieving SDG 3 (Good health and well-being). Organisations in these two areas are already aligning themselves in the ‘One Health’ movement. Another strategy can be to align with organisations for whom achievement of their goal has the greatest impact on animal welfare, even if the impact is not mutual e.g. by collaborating with organisations working to achieve SDG 16 (Peace justice and strong institutions) and SDG 4 (Quality education). Achieving these goals was considered to have a large impact on improving animal welfare, equivalent to that of achieving SDG 3. In summary, this study can help organisations working in the area of animal welfare identify previously untapped areas of potential support, so tailoring their efforts efficiently, while at the same time themselves supporting movement towards the Agenda 2030. Simply put, the co-benefits make collaboration worthwhile, potentially opening up opportunities that would be unavailable when organisations are working independently towards their own respective goals
Case-control study to detect protective factors on pig farms with low Salmonella prevalence
The prevalence of Salmonella in UK pigs is amongst the highest in Europe, highlighting the risk to public health and the need to investigate on-farm controls. The objective of this study was to identify factors currently in operation on pig farms that had maintained a low Salmonella seroprevalence. For this purpose a case-control study was designed and pig farms with a low (\u3c10%) seroprevalence were compared against two randomly selected control farms, sharing the same geographical region and production type. A total of 11,452 samples, including pooled and individual floor faeces and environmental samples from pigs and their vicinity were tested and prevalence examined. In addition, detailed questionnaires were completed during the farm visits to collect descriptive data for risk factor analysis. It was shown that control farms had significantly higher prevalence compared to the case farms (19.4% and 4.3% for pooled and 6.7% and 0.1% for individual samples, respectively). The two risk factor analyses identified multiple variables associated with Salmonella prevalence including variables related to feed, effectiveness of cleaning and disinfection, biosecurity and batch production
Falls Prediction in Care Homes Using Mobile App Data Collection
Falls are one of the leading causes of unintentional injury related deaths in older adults. Although, falls among elderly is a well documented phenomena; falls of care homes’ residents was under-researched, mainly due to the lack of documented data. In this study, we use data from over 1,769 care homes and 68,200 residents across the UK, which is based on carers who routinely documented the residents’ activities, using the Mobile Care Monitoring mobile app over three years. This study focuses on predicting the first fall of elderly living in care homes a week ahead. We intend to predict continuously based on a time window of the last weeks. Due to the intrinsic longitudinal nature of the data and its heterogeneity, we employ the use of Temporal Abstraction and Time Intervals Related Patterns discovery, which are used as features for classification. We had designed an experiment that reflects real-life conditions to evaluate the framework. Using four weeks of observation time window performed best
Prevalence of Salmonella in the offspring of sows vaccinated with a live-attenuated Salmonella Typhimurium vaccine
In this study, the efficacy of a live-attenuated Salmonella Typhimurium vaccine administered to pregnant sows in the breeding herd was evaluated as a means of reducing the prevalence of Salmonella infection in growing and finishing pigs. The results suggest no significant difference between the prevalence of Salmonella (all serovars) in the two groups of sows and their offspring. The lymph node and meat juice collected from carcasses of offspring showed no significant difference between the two groups, but the prevalence of Salmonella was significantly lower in the caecum content from pigs born of vaccinated sows. The farm had a very low prevalence of S. Typhimurium, which may explain the failure to detect any effect of the vaccine, as the majority of Salmonella on this farm was S. Derby
Assessing variation in utilization for acute myocardial infarction in New York State
a b s t r a c t Background: Wide variations exist in healthcare expenditures, though most prior studies have assessed aggregate utilization. We sought to examine healthcare utilization variation in New York State by assessing hospitals in peer groups of similar capabilities. Methods: Using charge data in New York State from the 2008 Statewide Planning and Research Cooperative System (SPARCS) and cost-to-charge ratios at the cost-center level drawn from Institutional Cost Reports, we calculated total, routine, and ancillary costs for patients discharged with an acute myocardial infarction (AMI) diagnosis in 2008. We assessed the correlation of these cost data to Hospital Referral Region (HRR) Medicare reimbursement data from the 2007 Dartmouth Atlas of Health Care. After describing hospital level cost variability, we examined characteristics associated with higher costs within peer groups of similar cardiac care capabilities. Results: We found greater costs in hospitals providing the highest level of cardiovascular services, with cardiac surgery capable hospitals and non-invasive hospitals having total costs of 9268 per AMI discharge, and ancillary costs of 4167 per AMI discharge, respectively. Substantial variability in utilization existed in all levels of hospitals and across individual departmental cost centers. The two factors most frequently associated with higher total and ancillary costs across peer groups were patient case mix index and major or minor teaching status. Conclusions: Significant variation in cost per AMI discharge exists even within peer groups of hospitals with similar cardiac care capabilities. Implications: These findings support measurement and analysis at the hospital level to further understand the reasons for variation in utilization
Resveratrol Targeting of Carcinogen-Induced Brain Endothelial Cell Inflammation Biomarkers MMP-9 and COX-2 is Sirt1-Independent
The occurrence of a functional relationship between the release of metalloproteinases (MMPs) and the expression of cyclooxygenase (COX)-2, two inducible pro-inflammatory biomarkers with important pro-angiogenic effects, has recently been inferred. While brain endothelial cells play an essential role as structural and functional components of the blood-brain barrier (BBB), increased BBB breakdown is thought to be linked to neuroinflammation. Chemopreventive mechanisms targeting both MMPs and COX-2 however remain poorly investigated. In this study, we evaluated the pharmacological targeting of Sirt1 by the diet-derived and antiinflammatory polyphenol resveratrol. Total RNA, cell lysates, and conditioned culture media from human brain microvascular endothelial cells (HBMEC) were analyzed using qRT-PCR, immunoblotting, and zymography respectively. Tissue scan microarray analysis of grade I–IV brain tumours cDNA revealed increased gene expression of Sirt-1 from grade I–III but surprisingly not in grade IV brain tumours. HBMEC were treated with a combination of resveratrol and phorbol 12-myristate 13-acetate (PMA), a carcinogen known to increase MMP-9 and COX-2 through NF-κB. We found that resveratrol efficiently reversed the PMA-induced MMP-9 secretion and COX-2 expression. Gene silencing of Sirt1, a critical modulator of angiogenesis and putative target of resveratrol, did not lead to significant reversal of MMP-9 and COX-2 inhibition. Decreased resveratrol inhibitory potential of carcinogen-induced IκB phosphorylation in siSirt1-transfected HBMEC was however observed. Our results suggest that resveratrol may prevent BBB disruption during neuroinflammation by inhibiting MMP-9 and COX-2 and act as a pharmacological NF-κB signal transduction inhibitor independent of Sirt1
Potential of Resveratrol Analogues as Antagonists of Osteoclasts and Promoters of Osteoblasts
The plant phytoalexin resveratrol was previously demonstrated to inhibit the differentiation and bone resorbing activity of osteoclasts, to promote the formation of osteoblasts from mesenchymal precursors in cultures, and inhibit myeloma cell proliferation, when used at high concentrations. In the current study, we screened five structurally modified resveratrol analogues for their ability to modify the differentiation of osteoclasts and osteoblasts and proliferation of myeloma cells. Compared to resveratrol, analogues showed an up to 5,000-fold increased potency to inhibit osteoclast differentiation. To a lesser extent, resveratrol analogues also promoted osteoblast maturation. However, they did not antagonize the proliferation of myeloma cells. The potency of the best-performing candidate in vitro was tested in vivo in an ovariectomy-induced model of osteoporosis, but an effect on bone loss could not be detected. Based on their powerful antiresorptive activity in vitro, resveratrol analogues might be attractive modulators of bone remodeling. However, further studies are required to establish their efficacy in vivo
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