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Climate and weather conditions may have substantial effects on the ecology of both parasites and hosts in natural populations. The strength and shape of the effects of weather on parasites and hosts are likely to change as global warming affects local climate. These changes may in turn alter fundamental elements of parasite–host dynamics. We explored the influence of temperature and precipitation on parasite prevalence in a metapopulation of avian hosts in northern Norway. We also investigated if annual change in parasite prevalence was related to winter climate, as described by the North Atlantic Oscillation (NAO). We found that parasite prevalence increased with temperature within-years and decreased slightly with increasing precipitation. We also found that a mild winter (positive winter NAO index) was associated with higher mean parasite prevalence the following year. Our results indicate that both local and large scale weather conditions may affect the proportion of hosts that become infected by parasites in natural populations. Understanding the effect of climate and weather on parasite–host relationships in natural populations is vital in order to predict the full consequence of global warming.
Paramedics Providing Palliative Care at Home was launched in two provinces, including a new clinical practice guideline, database, and paramedic training. The aim of this study was to evaluate patient/family satisfaction and paramedic comfort and confidence.
In Part A, we gathered perspectives of patients/families via surveys mailed at enrolment and telephone interviews after an encounter. Responses were reported descriptively and by thematic analysis. In Part B, we surveyed paramedics online pre- and 18 months post-launch. Comfort and confidence were scored on a 4-point Likert scale, and attitudes on a 7-point Likert scale, reported as the median (interquartile range [IQR]); analysis with Wilcoxon ranked sum/thematic analysis of free text.
In Part A, 67/255 (30%) enrolment surveys were returned. Three themes emerged: fulfilling wishes, peace of mind, and feeling prepared for emergencies. In 18 post-encounter interviews, four themes emerged: 24/7 availability, paramedic professionalism and compassion, symptom relief, and a plea for program continuation. Thematic saturation was reached with little divergence. In Part B, 235/1255 (18.9%) pre- and 267 (21.3%) post-surveys were completed. Comfort with providing palliative care without transport improved post launch (p = < 0.001) as did confidence in palliative care without transport (p = < 0.001). Respondents strongly agreed that all paramedics should be able to provide basic palliative care.
After implementation of the multifaceted Paramedics Providing Palliative Care at Home Program, paramedics describe palliative care as important and rewarding. The program resulted in high patient/family satisfaction; simply registering provides peace of mind. After an encounter, families particularly noted the compassion and professionalism of the paramedics.
Mutants of Bacillus subtilis can be developed to overproduce Val in vitro. It was hypothesized that addition of Bacillus subtilis mutants to pig diets can be a strategy to supply the animal with Val. The objective was to investigate the effect of Bacillus subtilis mutants on growth performance and blood amino acid (AA) concentrations when fed to piglets. Experiment 1 included 18 pigs (15.0±1.1 kg) fed one of three diets containing either 0.63 or 0.69 standardized ileal digestible (SID) Val : Lys, or 0.63 SID Val : Lys supplemented with a Bacillus subtilis mutant (mutant 1). Blood samples were obtained 0.5 h before feeding and at 1, 2, 3, 4, 5 and 6 h after feeding and analyzed for AAs. In Experiment 2, 80 piglets (9.1±1.1 kg) were fed one of four diets containing 0.63 or 0.67 SID Val : Lys, or 0.63 SID Val : Lys supplemented with another Bacillus subtilis mutant (mutant 2) or its parent wild type. Average daily feed intake, daily weight gain and feed conversion ratio were measured on days 7, 14 and 21. On day 17, blood samples were taken and analyzed for AAs. On days 24 to 26, six pigs from each dietary treatment were fitted with a permanent jugular vein catheter, and blood samples were taken for AA analysis 0.5 h before feeding and at 1, 2, 3, 4, 5 and 6 h after feeding. In experiment 1, Bacillus subtilis mutant 1 tended (P<0.10) to increase the plasma levels of Val at 2 and 3 h post-feeding, but this was not confirmed in Experiment 2. In Experiment 2, Bacillus subtilis mutant 2 and the wild type did not result in a growth performance different from the negative and positive controls. In conclusion, results obtained with the mutant strains of Bacillus subtilis were not better than results obtained with the wild-type strain, and for both strains, the results were not different than the negative control.
Introduction: Nova Scotia has a province wide reperfusion strategy for the treatment of patients presenting with acute ST-Elevation Myocardial Infarction (STEMI). Patients are referred for primary percutaneous coronary intervention (PPCI) if a first medical contact to device time can be achieved within 90 to 120 minutes; otherwise, fibrinolytic therapy is administered, as per guideline recommendations. Since 2011, Nova Scotian paramedics have been providing prehospital fibrinolysis (PHF) and prehospital catheterization (cath) lab activation for STEMI patients outside and within the PPCI catchment area, respectively. Patients who received fibrinolysis are transferred to a PCI facility if rescue PCI is required or if there are other indications for urgent intervention. This province wide approach is unique and the objective of this retrospective cohort study is to compare the impact of this approach on the primary outcome of 30-day mortality. Methods: For the study period, July 2011 to July 2013, STEMI patients who were diagnosed prehospital or in the ED who subsequently underwent reperfusion therapy were identified in the Emergency Health Services (EHS), Cardiovascular Information Systems (CVIS) and Cardiovascular Health Nova Scotia (CVHNS) databases. Baseline demographics and outcomes were then compared according to the treatment received: 1) PHF; 2) ED Fibrinolysis (EDF); 3) prehospital activated PPCI (EHS PPCI); and 4) ED activated PPCI (ED PPCI). Results: There were a total of 1107 STEMI patients identified during the study period, of whom 742 received lytic therapy (146 PHF; 596 EDF) and 332 underwent PPCI (202 EHS PPCI; 130 ED PPCI). Demographic variables were similar across the groups. The primary outcome of 30-day mortality was not significantly different across groups: 5 (3%) in PHF, 26 (4%) in EDF, 8 (4%) in EHS to PPCI and 2 (2%) in ED to PPCI. The number of rescue PCIs was 28 (19%) in PHF and 102 (17%) in EDF. Other outcomes (key timestamps) are pending. Conclusion: Our results show that the 30-day mortality was lowest for patients undergoing PPCI and slightly less for patients receiving pre-hospital fibrinolytic compared to those receiving ED fibrinolytic with no difference in the proportion requiring subsequent rescue PCI. The majority of patients in rural areas received EDF as opposed to PHF; pending results will show if this represents a delay in patient presentation after symptom onset.
Introduction: Patients who require end of life (EoL)/palliative care occasionally need assistance from paramedics. This review evaluated the evidence for paramedic-delivered EoL/palliative care interventions. Methods: The Canadian Prehospital Evidence-based Practice (PEP) Project methodology was used. A PubMed search was conducted, using Medical Subject headings and title/abstract key words. Titles and abstracts were reviewed for relevance. Studies were not required to be EMS based but must have focused on interventions available to EMS personnel. Included full text studies were scored by trained primary appraisers on a three-point Level of Evidence (LOE) scale (high = 1, moderate = 2 and low = 3) and three-point Direction of Evidence (DOE) scale (supportive, neutral, or opposing). Studies were categorized by clinical condition (n=5) and by intervention (n=25), and plotted on 3×3 (DOE × LOE) tables. The study primary outcome and setting were determined. Results: The search returned 3255 articles; 86 were selected for abstract review; with 30 full text articles ultimately included. Intervention recommendations were: LOE 1-supportive (n=3, 12%), 2-supportive (n=2, 8%), 3-supportive (n=2, 8%), 1-neutral (n=2, 8%), 2-neutral (n=2, 8%), 3-neutral (n=4, 16%). No primary studies were identified for 10 (40%) interventions. Conditions with 1-supportive studies were: ‘breathlessness’ and ‘analgesia’. ‘Secretions’ condition had no relevant evidence. Interventions with 1-supportive evidence were: Haldol for agitation (n=1), fentanyl and morphine for analgesia (n=3 and n=1), narcotics for breathlessness (n=1). No intervention had opposing evidence. Primary outcomes were more commonly related to symptom relief (n=26, 87%), safety (n=3, 10%), or tolerability (n=1, 3%). Only one included study was conducted in the EMS setting. Conclusion: Evidence for interventions used by paramedics in the treatment of patients requiring EoL/palliative care was identified, as were evidence gaps. Little research was conducted in the EMS setting, and most interventions had few studies. These PEP findings highlight topics requiring high quality EMS research specific to EoL/palliative care to inform this growing aspect of paramedic practice.
To limit tail biting incidence, most pig producers in Europe tail dock their piglets. This is despite EU Council Directive 2008/120/EC banning routine tail docking and allowing it only as a last resort. The paper aims to understand what it takes to fulfil the intentions of the Directive by examining economic results of four management and housing scenarios, and by discussing their consequences for animal welfare in the light of legal and ethical considerations. The four scenarios compared are: ‘Standard Docked’, a conventional housing scenario with tail docking meeting the recommendations for Danish production (0.7 m2/pig); ‘Standard Undocked’, which is the same as ‘Standard Docked’ but with no tail docking, ‘Efficient Undocked’ and ‘Enhanced Undocked’, which have increased solid floor area (0.9 and 1.0 m2/pig, respectively) provision of loose manipulable materials (100 and 200 g/straw per pig per day) and no tail docking. A decision tree model based on data from Danish and Finnish pig production suggests that Standard Docked provides the highest economic gross margin with the least tail biting. Given our assumptions, Enhanced Undocked is the least economic, although Efficient Undocked is better economically and both result in a lower incidence of tail biting than Standard Undocked but higher than Standard Docked. For a pig, being bitten is worse for welfare (repeated pain, risk of infections) than being docked, but to compare welfare consequences at a farm level means considering the number of affected pigs. Because of the high levels of biting in Standard Undocked, it has on average inferior welfare to Standard Docked, whereas the comparison of Standard Docked and Enhanced (or Efficient) Undocked is more difficult. In Enhanced (or Efficient) Undocked, more pigs than in Standard Docked suffer from being tail bitten, whereas all the pigs avoid the acute pain of docking endured by the pigs in Standard Docked. We illustrate and discuss this ethical balance using numbers derived from the above-mentioned data. We discuss our results in the light of the EU Directive and its adoption and enforcement by Member States. Widespread use of tail docking seems to be accepted, mainly because the alternative steps that producers are required to take before resorting to it are not specified in detail. By tail docking, producers are acting in their own best interests. We suggest that for the practice of tail docking to be terminated in a way that benefits animal welfare, changes in the way pigs are housed and managed may first be required.
Societal aging is expected to impact the use of emergency medical services (EMS). Older adults are known as high users of EMS. Our primary objective was to quantify the rate of EMS use by older adults in a Canadian provincial EMS system. Our secondary objective was to compare those transported to those not transported.
We analysed data from a provincial EMS database for emergency responses between January 1, 2010 and December 31, 2010 and included all older adults (≥65 years) requesting EMS for an emergency call. We described EMS use in relation to age, sex, and resources.
There were 30,653 emergency responses for older adults in 2010, representing close to 50% of the emergency call volume and an overall response rate of 202.8 responses per 1,000 population 65 years and older. The mean age was 79.9±8.5 years for those 57.3% who were female. The median paramedic-determined Canadian Triage and Acuity Scale (CTAS) score was 3 and the mean on-scene time was 24.2 minutes. Non-transported calls (12.3%) for the elderly involved predominantly (54.9%) female patients of similar mean age (78.3 years) but lower acuity (CTAS 5) and longer average on-scene times (32.6 minutes).
We confirmed the increasingly high rate of EMS use with age to be consistent with other industrialized populations. The low-priority and non-transport calls by older adults consumed considerable resources in this provincial system and might be the areas most malleable to meet the challenges facing EMS systems.
The objective of the current experiment was to compare the effects of supplementing mid-lactation dairy cows with all-rac-α-tocopheryl acetate (SyntvE), RRR-α-tocopheryl acetate (NatvE) or seaweed meal (Seaweed) in the presence of a Control group (no supplemental vitamin E or seaweed) on the concentration of α-tocopherol in plasma and milk, and antibody response following immunization. The hypothesis was that supplementation of dairy cows with vitamin E, regardless of its form, would increase plasma and milk α-tocopherol compared to the control diet and this incremental response would be bigger with NatvE than SyntvE. Furthermore, it was hypothesized that vitamin E, regardless of its form, will provide an improved adaptive immune response to immunization than the Control diet, and cows supplemented with Seaweed meal would produce better adaptive immune response following immunization than cows in the Control group. Twenty-four Norwegian Red (NR) dairy cows in their mid-lactation were allocated randomly to the four treatments in a replicated Latin square design. The cows were fed on a basal diet of silage and concentrate on top of which the experimental supplements were provided. Plasma and milk α-tocopherol concentrations were higher in NatvE and SyntvE groups than in the other two groups. The RRR-α-tocopherol stereoisomer was the predominant form (>0·86), in both plasma and milk, whereas the remaining part was largely made up of the other three 2R stereoisomers (RRS, RSR and RSS). In cows fed the Control, Seaweed and NatvE, the proportion of the RRR-α-tocopherol stereoisomer in plasma and milk constituted >0·97 of the total α-tocopherol. Mid-lactation NR dairy cows had higher than adequate levels of plasma α-tocopherol (9·99 mg/l) even when not supplemented with external source of vitamin E, suggesting that with a good quality silage these cows may not be at risk of vitamin E deficiency. Furthermore, the present study shows that dairy cows in mid to late lactation have preferential uptake of RRR stereoisomer of α-tocopherol compared with other stereoisomers. All cows responded well to immunization with different antigens, but there were no significant group effects of the diet on the immune response measured.
Clostridium difficile infection (CDI) places a high burden on the US healthcare system. Recurrent CDI (RCDI) occurs frequently. Recently proposed guidelines from the American College of Gastroenterology (ACG) and the American Gastroenterology Association (AGA) include fecal microbiota transplantation (FMT) as a therapeutic option for RCDI. The purpose of this study was to estimate the cost-effectiveness of FMT compared with vancomycin for the treatment of RCDI in adults, specifically following guidelines proposed by the ACG and AGA.
We constructed a decision-analytic computer simulation using inputs from the published literature to compare the standard approach using tapered vancomycin to FMT for RCDI from the third-party payer perspective. Our effectiveness measure was quality-adjusted life years (QALYs). Because simulated patients were followed for 90 days, discounting was not necessary. One-way and probabilistic sensitivity analyses were performed.
Base-case analysis showed that FMT was less costly ($1,669 vs $3,788) and more effective (0.242 QALYs vs 0.235 QALYs) than vancomycin for RCDI. One-way sensitivity analyses showed that FMT was the dominant strategy (both less expensive and more effective) if cure rates for FMT and vancomycin were ≥70% and <91%, respectively, and if the cost of FMT was <$3,206. Probabilistic sensitivity analysis, varying all parameters simultaneously, showed that FMT was the dominant strategy over 10, 000 second-order Monte Carlo simulations.
Our results suggest that FMT may be a cost-saving intervention in managing RCDI. Implementation of FMT for RCDI may help decrease the economic burden to the healthcare system.
Norovirus outbreaks occur frequently in Denmark and it can be difficult to establish whether apparently independent outbreaks have the same origin. Here we report on six outbreaks linked to frozen raspberries, investigated separately over a period of 3 months. Norovirus from stools were sequence-typed; including extended sequencing of 1138 bp encompassing the hypervariable P2 region of the capsid gene. Norovirus was detected in 27 stool samples. Genotyping showed genotype GI.Pb_GI.6 (polymerase/capsid) with 100% identical sequences. Samples from five outbreaks were furthermore identical over the variable capsid P2 region. In one outbreak at a hospital canteen, frozen raspberries was associated with illness by cohort investigation (relative risk 6·1, 95% confidence interval 3·2–11). Bags of raspberries suspected to be the source were positive for genogroup I and II noroviruses, one typable virus was genotype GI.6 (capsid). These molecular investigations showed that the apparently independent outbreaks were the result of one contamination event of frozen raspberries. The contaminated raspberries originated from a single producer in Serbia and were originally not considered to belong to the same batch. The outbreaks led to consultations and mutual visits between producers, investigators and authorities. Further, Danish legislation was changed to make heat-treatment of frozen raspberries compulsory in professional catering establishments.
We consider two-dimensional one-sided convection of a solute in a fluid-saturated porous medium, where the solute decays via a first-order reaction. Fully nonlinear convection is investigated using high-resolution numerical simulations and a low-order model that couples the dynamic boundary layer immediately beneath the distributed solute source to the slender vertical plumes that form beneath. A transient-growth analysis of the boundary layer is used to characterise its excitability. Three asymptotic regimes are investigated in the limit of high Rayleigh number
, in which the domain is considered deep, shallow or of intermediate depth, and for which the Damköhler number
is respectively large, small or of order unity. Scaling properties of the flow are identified numerically and rationalised via the analytic model. For fully established high-
convection, analysis and simulation suggest that the time-averaged solute transfer rate scales with
and the plume horizontal wavenumber with
, with coefficients modulated by
in each case. For large
, the rapid reaction rate limits the plume depth and the boundary layer restricts the rate of solute transfer to the bulk, whereas for small
the average solute transfer rate is ultimately limited by the domain depth and the convection is correspondingly weaker.
Tail biting is a serious animal welfare and economic problem in pig production. Tail docking, which reduces but does not eliminate tail biting, remains widespread. However, in the EU tail docking may not be used routinely, and some ‘alternative’ forms of pig production and certain countries do not allow tail docking at all. Against this background, using a novel approach focusing on research where tail injuries were quantified, we review the measures that can be used to control tail biting in pigs without tail docking. Using this strict criterion, there was good evidence that manipulable substrates and feeder space affect damaging tail biting. Only epidemiological evidence was available for effects of temperature and season, and the effect of stocking density was unclear. Studies suggest that group size has little effect, and the effects of nutrition, disease and breed require further investigation. The review identifies a number of knowledge gaps and promising avenues for future research into prevention and mitigation. We illustrate the diversity of hypotheses concerning how different proposed risk factors might increase tail biting through their effect on each other or on the proposed underlying processes of tail biting. A quantitative comparison of the efficacy of different methods of provision of manipulable materials, and a review of current practices in countries and assurance schemes where tail docking is banned, both suggest that daily provision of small quantities of destructible, manipulable natural materials can be of considerable benefit. Further comparative research is needed into materials, such as ropes, which are compatible with slatted floors. Also, materials which double as fuel for anaerobic digesters could be utilised. As well as optimising housing and management to reduce risk, it is important to detect and treat tail biting as soon as it occurs. Early warning signs before the first bloody tails appear, such as pigs holding their tails tucked under, could in future be automatically detected using precision livestock farming methods enabling earlier reaction and prevention of tail damage. However, there is a lack of scientific studies on how best to respond to outbreaks: the effectiveness of, for example, removing biters and/or bitten pigs, increasing enrichment, or applying substances to tails should be investigated. Finally, some breeding companies are exploring options for reducing the genetic propensity to tail bite. If these various approaches to reduce tail biting are implemented we propose that the need for tail docking will be reduced.
Motivated by processes occurring during
sequestration in an underground saline aquifer, we examine two-dimensional convection in a finite-depth porous medium induced by a solute introduced at the upper boundary. Once dissolved, the solute concentration is assumed to decay via a first-order chemical reaction, restricting the depth over which solute can penetrate the domain. Using spectral and asymptotic methods, we explore the resulting convective mixing using linear stability analysis, computation of nonlinear steady solution branches and time-dependent simulations, as a function of Rayleigh number, Damköhler number and domain size. Long-wave eigenmodes show how deep recirculation can be driven by a shallow solute field while explicit approximations are derived for the growth of short-wave eigenmodes. Steady solution branches undergo numerous secondary bifurcations, forming an intricate network of mixed states. Although many of these states are unstable, some play an important role in organising the phase space of time-dependent states, providing approximate bounds for time-averaged mixing rates.
A growing body of research has documented structural and functional brain development during adolescence, yet little is known about neurochemical changes that occur during this important developmental period. Magnetic resonance spectroscopy (MRS) is a well-developed technology that permits the in vivo quantification of multiple brain neurochemicals relevant to neuronal health and functioning. However, MRS technology has been underused in exploring normative developmental changes during adolescence and the onset of alcohol and drug use and abuse during this developmental period. This review begins with a brief overview of normative cognitive and neurobiological development during adolescence, followed by an introduction to MRS principles. The subsequent sections provide a comprehensive review of the existing MRS studies of development and cognitive functioning in healthy children and adolescents. The final sections of this article address the potential application of MRS in identifying neurochemical predictors and consequences of alcohol use and abuse in adolescence. MRS studies of adolescent populations hold promise for advancing our understanding of neurobiological risk factors for psychopathology by identifying the biochemical signatures associated with healthy brain development, as well as neurobiological and cognitive correlates of alcohol and substance use and abuse.
To examine the opinions of stakeholders on strategies to improve dietary quality of Supplemental Nutrition Assistance Program (SNAP) participants.
Participants answered a thirty-eight-item web-based survey assessing opinions and perceptions of SNAP and programme policy changes.
Survey of 522 individuals with stakeholder interest in SNAP, conducted in October through December 2011.
The top three barriers to improving dietary quality identified were: (i) unhealthy foods marketed in low-income communities; (ii) the high cost of healthy foods; and (iii) lifestyle challenges faced by low-income individuals. Many respondents (70 %) also disagreed that current SNAP benefit levels were adequate to maintain a healthy diet. Stakeholders believed that vouchers, coupons or monetary incentives for purchasing healthful foods might have the greatest potential for improving the diets of SNAP participants. Many respondents (78 %) agreed that sodas should not be eligible for purchases with SNAP benefits. More than half (55 %) believed retailers could easily implement such restrictions. A majority of respondents (58 %) agreed that stores should stock a minimum quantity of healthful foods in order to be certified as a SNAP retailer, and most respondents (83 %) believed that the US Department of Agriculture should collect data on the foods purchased with SNAP benefits.
Results suggest that there is broad stakeholder support for policies that align SNAP purchase eligibility with national public health goals of reducing food insecurity, improving nutrition and preventing obesity.
Research is essential for the development of evidence-based emergency medical services (EMS) systems of care. When resources are scarce and gaps in evidence are large, a national agenda may inform the growth of EMS research in Canada. This mixed methods consensus study explores current barriers and existing strengths within Canadian EMS research, provides recommendations, and suggests EMS topics for future study.
Purposeful sampling was employed to invite EMS research stakeholders from various roles across the country. Study phases consisted of 1) baseline interviews of a subsample, 2) roundtable discussion, and 3) an online Delphi survey, in which participants scored each statement for importance. Consensus was defined a priori and met if 80% scored a statement as “important” or “very important.”
Fifty-three stakeholders participated, representing researchers (37.7%), EMS administrators (24.6%), clinicians/ providers (20.7%), and educators (17.0%). Participation rates were as follows: interviews, 13 of 13 (100%); roundtable, 47 of 53 (89%); survey round 1, 50 of 53 (94%); survey round 2, 47 of 53 (89%); and survey round 3, 40 of 53 (75%). A total of 141 statements were identified as important: 20 barriers, 54 strengths/opportunities, 31 recommendations, and 36 suggested topics for future research. Like statements were synthesized, resulting in barriers (n 5 10), strengths/opportunities (n 5 24), and recommendations (n 5 19), which were categorized as time, opportunities, and funding; education and mentorship; culture of research and collaboration; structure, process, and outcome of research; EMS and paramedic practice; and the future of the EMS Research Agenda.
Consensus-based key messages from this agenda should be considered when designing, funding, and publishing EMS research and will advance EMS research locally, regionally, and nationally.