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We evaluated the utility of vancomycin-resistant Enterococcus (VRE) surveillance by varying 2 parameters: admission versus weekly surveillance and perirectal swabbing versus stool sampling.
Prospective, patient-level surveillance program of incident VRE colonization.
Liver transplant surgical intensive care unit (SICU) of a tertiary-care referral medical center with a high prevalence of VRE.
All patients admitted to the SICU from June to August 2015.
We conducted a point-prevalence estimate followed by admission and weekly surveillance by perirectal swabbing and/or stool sampling. Incident colonization was defined as a negative screen followed by positive surveillance. VRE was detected by culture on Remel Spectra VRE chromogenic agar. Microbiologically-confirmed VRE bloodstream infections (BSIs) were tracked for 2 months. Statistical analyses were calculated using the McNemar test, the Fisher exact test, the t test, and the χ2 test.
In total, 91 patients underwent VRE surveillance testing. The point prevalence of VRE colonization was 60.9%; VRE prevalence on admission was 30.1%. Weekly surveillance identified an additional 7 of 28 patients (25.0%) with incident colonization. VRE BSIs were more common in VRE-colonized patients than in noncolonized patients (8 of 43 vs 2 of 48; P=.028). In a direct comparison, perirectal swabs were more sensitive than stool samples in detecting VRE (64 of 67 vs 56 of 67; P=.023). Compliance with perirectal swabbing was 89% (201 of 226) compared to 56% (127 of 226) for stool collection (P≤0.001).
We recommend weekly VRE surveillance over admission-only screening in high-burden units such as liver transplant SICUs. Perirectal swabs had greater collection compliance and sensitivity than stool samples, making them the preferred methodology. Further work may have implications for antimicrobial stewardship and infection control.
Although it is well established that changes in dietary iron (Fe) intakes can influence copper (Cu) metabolism in animals, little attention has been paid to their importance in causing Cu deficiency in ruminants. The realization that silages frequently contain large amounts of Fe, mainly as a soil contaminant, prompted us to assess the potency of Fe as a Cu antagonist and to compare its effects with those of molybdenum (Mo).
In one experiment, 27 male Friesian calves, aged about 3 weeks, were allocated to three treatment groups and given a milk-substitute ration containing 2.5 mg Cu and 50, 250 or 500 mg Fe (as FeCl3.6H20)/kg DM. Liver biopsies were taken after 8 weeks and analyzed for Cu and Fe. As expected, tissue Fe increased by as much as 50% with increasing Fe intake. However, there were no effects of Fe on hepatic Cu retention in these pre-ruminant calves (liver Cu was 343, 372 and 390 mg/kg DM, respectively: SEM = 40).
A significant proportion of the grass silage fed to lactating dairy cows may be of only modest quality due either to delayed harvesting and/or poor ensiling conditions. In such situations, both total feed intake and milk production are likely to be compromised with the consequent need to feed more concentrates. Part of this effect is considered to be due to the development of a solid mass of digesta in the rumen, with loss of the normal layered or biphasic stratification of rumen contents. Under such conditions, rumen motility, rate of forage digestion and hence voluntary feed intake will be compromised. Mertens (1997) stressed that chemical definition of dietary fibre such as neutral- (NDF) or acid-detergent (ADF) fibre content was an inadequate description of the fibre content of a diet as it affects rumen function and animal performance. Consequently he proposed both effective NDF (eNDF; ability of a feed to replace a roughage with no negative effect on milk fat content) and physically effective NDF (peNDF; a measure of the physical properties of fibre as it stimulates chewing activity and development of the biphasic stratification of rumen contents) as additional descriptors of the physical characteristics of dietary fibre but to date these concepts have attracted limited attention in the UK. This study examined the effect of replacing increasing amounts of grass silage (GS) on a dry matter (DM) basis in a silage:concentrate ration with pressed sugar beet pulp (PP) on various processes of digestion in the rumen of lactating dairy cows, specifically in relation to chewing activity and rumen mat density.
The complete replacement of soyabean meal by maize distillers grains (MDG) in dairy cow diets had no significant effects on milk production, rumen digestion or the supply of non-ammonia N to the duodenum (Sutton et al., 2000; Phipps et al., 2001). The present experiment was designed to extend this work by examining the response when barley (BDG) or wheat (WDG) distillers grains replaced soyabean meal.
Maize distillers grains (MDG) are a traceable and valuable energy and protein feed for dairy cows (Owen and Larson, 1991) but little is known about the ability of UK MDG to replace more conventional protein sources, particularly their effects on the supply of protein to the cow. The purpose of the present experiment was to examine the effects of replacing soyabean meal with MDG on digestion in the rumen and flow of protein to the duodenum of lactating dairy cows.
Escherichia coli O157 are zoonotic bacteria for which cattle are an important reservoir. Prevalence estimates for E. coli O157 in British cattle for human consumption are over 10 years old. A new baseline is needed to inform current human health risk. The British E. coli O157 in Cattle Study (BECS) ran between September 2014 and November 2015 on 270 farms across Scotland and England & Wales. This is the first study to be conducted contemporaneously across Great Britain, thus enabling comparison between Scotland and England & Wales. Herd-level prevalence estimates for E. coli O157 did not differ significantly for Scotland (0·236, 95% CI 0·166–0·325) and England & Wales (0·213, 95% CI 0·156–0·283) (P = 0·65). The majority of isolates were verocytotoxin positive. A higher proportion of samples from Scotland were in the super-shedder category, though there was no difference between the surveys in the likelihood of a positive farm having at least one super-shedder sample. E. coli O157 continues to be common in British beef cattle, reaffirming public health policy that contact with cattle and their environments is a potential infection source.
Understanding the benefits and outcomes of Canada's public investment in Arctic science and associated community–researcher partnerships represents a significant challenge for government. This paper presents a capital assets-based approach to conceptualising northern research partnership development processes and assessing the potential outcomes. By more explicitly considering the pre- and post-partnership asset levels (that is, social, human, physical, financial and natural assets) for different collaborators, the potential benefits and challenges associated with community–researcher partnerships can be collaboratively assessed. In order to help refine this approach, we conducted a survey of those involved in developing and maintaining community–researcher partnerships across Arctic Canada. Results indicate that the proposed approach could be useful for research funding agencies seeking to better understand partnership outcomes and promote more effective community–researcher interactions. Challenges include adequately capturing the qualitative nature of different capital assets, pointing to future research and policy needs. Better understanding the role of research in northern development has the potential to improve northern research, policy and practice.
The Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD) is a web-based, open access, decision-support tool designed to assist scientists, non-governmental organisations and policy-makers working to meet the management objectives as set forth by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) and other components of the Antarctic Treaty System (ATS) (that is, Consultative Meetings and the ATS Committee on Environmental Protection). MAPPPD was designed specifically to complement existing efforts such as the CCAMLR Ecosystem Monitoring Program (CEMP) and the ATS site guidelines for visitors. The database underlying MAPPPD includes all publicly available (published and unpublished) count data on emperor, gentoo, Adélie and chinstrap penguins in Antarctica. Penguin population models are used to assimilate available data into estimates of abundance for each site and year. Results are easily aggregated across multiple sites to obtain abundance estimates over any user-defined area of interest. A front end web interface located at www.penguinmap.com provides free and ready access to the most recent count and modelled data, and can act as a facilitator for data transfer between scientists and Antarctic stakeholders to help inform management decisions for the continent.
Experimental data show Apollo 11 and 12 lava compositions to be controlled by fractional crystallization close to the lunar surface, in a process which yields achondrite-like igneous rocks as underlying complementary crystal accumulates. Volatilization losses during eruption can account for most other chemical differences between lunar lavas and common terrestrial magmas. No specific hypotheses of the composition, mineralogy, or origin of lunar interior can be sustained until the extent of these processes is known. A terrestrial upper-mantle-type lunar interior cannot yet be excluded. The assumption that maria surface lavas are primary partial melts is unjustified and leads to a postulated lunar interior with too low Mg/Mg+Fe to serve as a source for Apollo 14 and other igneous liquids. Other workers' uncontrolled visual estimates of crystallinity in experimental charges, purporting to show that maria lavas were not modified by low pressure fractionation, are irreconcilable with the chemistry of the residual liquids developed in our ‘reversed’ equilibrium experiments. The undesirability of using glass as a starting material for this type of experiment is re-emphasized.
To evaluate the impact of discontinuation of contact precautions (CP) for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) and expansion of chlorhexidine gluconate (CHG) use on the health system.
We compared hospital-wide laboratory-identified clinical culture rates (as a marker of healthcare-associated infections) 1 year before and after routine CP for endemic MRSA and VRE were discontinued and CHG bathing was expanded to all units. Culture data from patients and cost data on material utilization were collected. Nursing time spent donning personal protective equipment was assessed and quantified using time-driven activity-based costing.
Average positive culture rates before and after discontinuing CP were 0.40 and 0.32 cultures/100 admissions for MRSA (P=.09), and 0.48 and 0.40 cultures/100 admissions for VRE (P=.14). When combining isolation gown and CHG costs, the health system saved $643,776 in 1 year. Before the change, 28.5% intensive care unit and 19% medicine/surgery beds were on CP for MRSA/VRE. On the basis of average room entries and donning time, estimated nursing time spent donning personal protective equipment for MRSA/VRE before the change was 45,277 hours/year (estimated cost, $4.6 million).
Discontinuing routine CP for endemic MRSA and VRE did not result in increased rates of MRSA or VRE after 1 year. With cost savings on materials, decreased healthcare worker time, and no concomitant increase in possible infections, elimination of routine CP may add substantial value to inpatient care delivery.
This is the official guideline endorsed by the specialty associations involved in the care of head and neck cancer patients in the UK. It identifies the current evidence base and role of health-related quality of life assessment for this group of patients.
• Health-related quality of life is integral to treatment planning, refining treatment protocols, and more personalised follow-up support. (G)
• Health-related quality of life and patient concerns should be regularly assessed during patient care. (G)
• Health-related quality of life assessment and patient concerns on an individual patient basis can be helpful to trigger multi-professional support and interventions. (G)
The technology leading to very large aperture telescopes and their optics has progressed well in the period since 1984 and plans for many new large aperture telescopes have been made. Focal plane instrumentation continues to become more sophisticated or more efficient: multi-object capabilities, automatic instrument control and operation, and increasing use of CCDs are examples of areas to which this applies. The proportion of time devoted to observations using two-dimensional photoelectronic detectors has grown substantially at many observatories, particularly with telescopes of moderate aperture; and the use of high quantum efficiency array detectors is now being extended into the infrared spectral region. Important advances have also been made in instrumentation and techniques for ground-based high angular resolution interferometry.
We applied three statistical classification techniques—linear discriminant analysis (LDA), logistic regression, and random forests—to three astronomical datasets associated with searches for interstellar masers. We compared the performance of these methods in identifying whether specific mid-infrared or millimetre continuum sources are likely to have associated interstellar masers. We also discuss the interpretability of the results of each classification technique. Non-parametric methods have the potential to make accurate predictions when there are complex relationships between critical parameters. We found that for the small datasets the parametric methods logistic regression and LDA performed best, for the largest dataset the non-parametric method of random forests performed with comparable accuracy to parametric techniques, rather than any significant improvement. This suggests that at least for the specific examples investigated here accuracy of the predictions obtained is not being limited by the use of parametric models. We also found that for LDA, transformation of the data to match a normal distribution led to a significant improvement in accuracy. The different classification techniques had significant overlap in their predictions; further astronomical observations will enable the accuracy of these predictions to be tested.
An important component of northern research in Canada has been a strong emphasis on local participation. However, the policy and permit landscape for community participation therein is heterogeneous and presents specific challenges in promoting effective partnerships between researchers and local participants. We conducted a survey of northern research stakeholders across Canada in order better to understand the benefits and challenges associated with research partnerships with a view to informing northern research policy and practice. We found that local engagement at the proposal and research design phases, the hiring of community researchers and engagement of local persons at the results dissemination phase were important factors affecting success. Respondents also indicated a lack of social capital (trust and reciprocity) between researchers and communities as placing a negative impact on science partnerships. Overall, researchers were perceived to benefit more from research partnerships than their community counterparts. Partnerships in northern research will possibly require further decentralisation of power to achieve the policy objectives of local community participation. This could be achieved, in part, by allowing non-academic principal investigators to receive funding, or by involving communities in research priority-setting, proposal review and funding allocation processes.
The ultraviolet spectra of B stars obtained with the sky scan telescope in the TD1 satellite have been used to obtain narrow-band magnitudes at several wavelengths. These photometric bands have an effective half-width of 100 Å. We have proposed a two-dimensional classification scheme based on ultraviolet colours, and some preliminary results are presented.
The mammalian brain's decision mechanism may utilise a distributed network of positive feedback loops to integrate, over time, noisy sensory evidence for and against a particular choice. Such loops would mitigate the effects of noise and have the benefit of decoupling response size from the strength of evidence, which could assist animals in acting early at the first signs of opportunity or danger. This hypothesis is explored in the context of the sensorimotor control circuitry underlying eye movements, and in relation to the hypothesis that the basal ganglia serve as a central switch acting to control the competitive accumulation of sensory evidence in positive feedback loops representing alternative actions. Results, in support of these proposals, are presented from a systems-level computational model of the primate oculomotor control. This model is able to reproduce behavioural data relating strength of sensory evidence to response time and accuracy, while also demonstrating how the basal ganglia and related oculomotor circuitry might work together to manage the initiation, control, and termination of the decision process over time.
Whether it is a cheetah deciding whether its prey is veering left or right, a rabbit deciding whether that movement in the bushes is friend or foe, or a poker player wondering if his opponent has a stronger hand, infinitesimally small variations in sensory input can give rise to vastly different behavioural outcomes: the cheetah veers left and not right, the rabbit flees or continues grazing, the card player bets a month's salary or folds. The outcome of such decisions can be critical, even a matter of life or death, which is why there will have been tremendous evolutionary pressure to develop decision-making mechanisms that can extract maximal utility from limited sensory information. In this chapter, using the oculomotor system as an exemplar, we argue that the vertebrate basal ganglia (BG) are one of the results of that evolutionary pressure and explore how these structures tame and exploit positive feedback loops (henceforth PFBLs) within the brain in order to make the most of limited information.