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Frozen raw breaded chicken products (FRBCP) have been identified as a risk factor for Salmonella infection in Canada. In 2017, Canada implemented whole genome sequencing (WGS) for clinical and non-clinical Salmonella isolates, which increased understanding of the relatedness of Salmonella isolates, resulting in an increased number of Salmonella outbreak investigations. A total of 18 outbreaks and 584 laboratory-confirmed cases have been associated with FRBCP or chicken since 2017. The introduction of WGS provided the evidence needed to support a new requirement to control the risk of Salmonella in FRBCP produced for retail sale.
For livestock production systems to play a positive role in global food security, the balance between their benefits and disbenefits to society must be appropriately managed. Based on the evidence provided by field-scale randomised controlled trials around the world, this debate has traditionally centred on the concept of economic-environmental trade-offs, of which existence is theoretically assured when resource allocation is perfect on the farm. Recent research conducted on commercial farms indicates, however, that the economic-environmental nexus is not nearly as straightforward in the real world, with environmental performances of enterprises often positively correlated with their economic profitability. Using high-resolution primary data from the North Wyke Farm Platform, an intensively instrumented farm-scale ruminant research facility located in southwest United Kingdom, this paper proposes a novel, information-driven approach to carry out comprehensive assessments of economic-environmental trade-offs inherent within pasture-based cattle and sheep production systems. The results of a data-mining exercise suggest that a potentially systematic interaction exists between ‘soil health’, ecological surroundings and livestock grazing, whereby a higher level of soil organic carbon (SOC) stock is associated with a better animal performance and less nutrient losses into watercourses, and a higher stocking density with greater botanical diversity and elevated SOC. We contend that a combination of farming system-wide trials and environmental instrumentation provides an ideal setting for enrolling scientifically sound and biologically informative metrics for agricultural sustainability, through which agricultural producers could obtain guidance to manage soils, water, pasture and livestock in an economically and environmentally acceptable manner. Priority areas for future farm-scale research to ensure long-term sustainability are also discussed.
To develop sustainable grazing systems, an understanding of the complex interactions between competing plant species and grazing herbivores is needed. An understanding of dietary preference is a prerequisite to predicting how much and from which plant species animals select. This work initially concentrated on dietary preferences of sheep grazing perennial ryegrass and white clover swards and was then extended to other animal species to test the generality of our findings.
Previous research has shown relatively diminished medial prefrontal cortex activation and heightened psychophysiological responses during the recollection of personal events in post-traumatic stress disorder (PTSD), but the origin of these abnormalities is unknown. Twin studies provide the opportunity to determine whether such abnormalities reflect familial vulnerabilities, result from trauma exposure, or are acquired characteristics of PTSD.
In this case–control twin study, 26 male identical twin pairs (12 PTSD; 14 non-PTSD) discordant for PTSD and combat exposure recalled and imagined trauma-unrelated stressful and neutral life events using a standard script-driven imagery paradigm during functional magnetic resonance imaging and concurrent skin conductance measurement.
Diminished activation in the medial prefrontal cortex during Stressful v. Neutral script-driven imagery was observed in the individuals with PTSD, relative to other groups.
Diminished medial prefrontal cortex activation during Stressful v. Neutral script-driven imagery may be an acquired characteristic of PTSD. If replicated, this finding could be used prospectively to inform diagnosis and the assessment of treatment response.
SAX, an acronym for “Satellite Italiano per Astronomia a raggi X”, now renamed “BeppoSAX” in honor of Giuseppe Occhialini, is the first X-ray mission sensitive in the very broad energy range between 0.1 and 300 keV (Boella et al. 1997a). The Narrow Field Instruments (NFI) have approximately 1° fields of view and consist of the imaging low- and medium-energy concentrator spectrometers (LECS, 0.1-10 keV, Parmar et al. 1997; and MECS, 1-10 keV, Boella et al. 1997b), and the non-imaging high pressure gas scintillation proportional counter (HPGSPC, 3-120 keV, Manzo et al. 1997) and Phoswich detector system (PDS, 15-300 keV, Frontera et al. 1997). All the NFI are coaligned and are normally operated simultaneously. In addition, the payload includes two wide field cameras (WFC, 2-30 keV; Jager et al. 1997) which observe in directions perpendicular to the NFI. These allow the detection of X-ray transient phenomena, as well as long-term variability studies.
Head lice (Pediculus humanus capitis) infestations are a public health concern. The insecticidal properties of the Australian native plant Kunzea ambigua (commonly known as tick bush) have been documented. In this study, we tested activity of kunzea oil (KO) against head lice through in vitro bioassays. Head lice were exposed to filter paper treated with either KO, as either a 5 or 100% oil, or commercial formulations containing either permethrin or tea tree oil (TTO) for 120 min. Head lice exposure to KO, both as a 5 and 100% solution oil, resulted in 100% mortality within 120 min with a mean survival times of 17·1 and 34·8 min, respectively. There was no significant difference between the mean mortality of head lice exposed to 5% KO (17·1 ± 1·0; 95% CI: 115·2–19·0) and 5% TTO (21·2 ± 1·9; 95% CI: 17·4–25·1). This study revealed, for the first time, that KO holds great potential as an effective alternative to current active ingredients contained within commercial pediculicide formulations.
Background: Video feedback (VF) interventions effectively reduce social anxiety symptoms and negative self-perception, particularly when they are preceded by cognitive preparation (CP) and followed by cognitive review. Aims: In the current study, we re-examined data from a study on the efficacy of a novel VF intervention for individuals high in social anxiety to test the hypothesis that physical appearance anxiety would moderate the effects of VF. Method: Data were analyzed from 68 socially anxious participants who performed an initial public speech, and were randomly assigned to an Elaborated VF condition (VF plus cognitive preparation and cognitive review), a Standard VF condition (VF plus cognitive preparation) or a No VF condition (exposure alone), and then performed a second speech. Results: As hypothesized, when appearance concerns were low, both participants who received Elaborated and Standard VF were significantly less anxious during speech 2 than those in the No VF condition. However, when levels of appearance concern were high, neither Elaborated nor Standard VF reduced anxiety levels during speech 2 beyond the No VF condition. Conclusions: Results from our analog sample suggest the importance of tailoring treatment protocols to accommodate the idiosyncratic concerns of socially anxious patients.
The Management Board of the UK Actuarial Profession is undertaking a thought leadership cross-practice research project on the use of discount rates by UK actuaries. The timing for this research is particularly appropriate as there is a convergence of interest in discount rates from within and outside of the Profession. Discount rates are at the heart of most actuarial calculations and are of significant public interest. As part of this project the Management Board wants a full and open debate on the significant issues and this paper is the next step in stimulating that debate, giving another opportunity to influence the future direction of the project.
The Management Board set up a small cross-practice steering committee to drive the project. The Discount Rate Steering Committee identified five areas of work that would be needed to achieve the project's overall objectives:
(1)A survey of current practices.
(2)A survey of existing research and debate.
(3)Developing a common language for communicating discount rates and risk.
(4)Developing a common framework for the future where appropriate.
(5)Considering the impact of any changes.
Although the Profession does not set standards for technical work it still has a significant role for undertaking research in the public interest which supports the competence of its members and the furtherance of actuarial science.
Chinu Patel and Chris Daykin were commissioned to undertake the first part of this work and they presented their preliminary output at a forum of thought leaders across the Profession and externally on 23 March 2010. Their report “Actuaries and Discount Rates” was subsequently published in May 2010 and presented the results of their initial research into past and current practice in the setting of discount rates in the UK, and a survey of existing research and debate. A summary of that report is included in Section 2 of this paper.
Following consultation both within and outside the Actuarial Profession, this interim paper now takes forward the ideas and initial steps developed by Patel & Daykin and looks at developing a common language and framework for using discount rates in actuarial work. The Discount Rate Steering Committee is making a number of recommendations to the Profession which are intended to help actuaries speak clearly and with authority in future debates about discount rates and to support actuaries in communicating impartially and effectively. The recommendations are set out in Section 6 of the report following the development of the framework in Sections 3–5. As part of further developing the recommendations to the Profession, the Discount Rate Steering Committee is seeking views from stakeholders from inside and outside of the Profession. This will be undertaken throughout January and February 2011 and, as part of this process, the report will be presented at sessional research events in Edinburgh (17 January 2011) and London (31 January 2011). The Discount Rate Steering Committee is committed to seeking feedback on the recommendations and hopes this paper will give those inside and outside the Profession an opportunity to add to the dialogue so that as wide a range of potential views as possible is heard.
In this paper, the steering committee has concentrated on the more technical aspects of developing a framework for communicating discount rates and associated risks and the report is aimed primarily at actuaries. But the committee is mindful of the need to help actuaries communicate more clearly with those outside the Profession. During the first half of 2011, the steering committee will therefore concentrate on producing a document in less technical language to help non-actuaries understand the issues around the selection and use of discount rates and to help actuaries in their communication with stakeholders.
Energy use is inexorably woven into the fabric of modern civilization. Human well-being, economic productivity, and national security all depend on the availability of plentiful and affordable energy supplies. However, over the past half century, we have come to understand that continued growth of energy use along the lines of current energy systems will lead to unacceptable consequences for the Earth's climate and oceans. Maintaining and increasing the access to energy services to satisfy crucial societal needs requires the development of a sustainable global energy system that transitions away from energy supply options with high greenhouse gas (GHG) emissions and unhealthy air pollutants. Disparity in energy access is also not sustainable. We must provide sufficient energy for the estimated 1.6 billion people who do not have access to modern energy systems today. Fortunately, plentiful energy resources are available to meet our needs, and technology pathways for making this transition exist. Continuing to lower the cost and increase the reliability of energy from sustainable energy resources will facilitate this transition. Changing the world's energy systems to reduce GHG emissions is one of the critical challenges that humans must face in this century. The required transition can begin now with improvements in efficiency of energy conversion and use, and with continuing deployment over the coming decades of a variety of existing and innovative technologies. With continuing attention to energy conversions that minimize wastes, have low life-cycle impacts, and maximize recycling of materials, a set of sustainable energy systems can be created.
Feeding, clothing, and housing a growing world population will be a significant challenge in this century, as will supplying the fresh water, heat, lighting, and transportation we will need to live comfortable and productive lives. This chapter discusses energy sustainability, with emphasis on the requirement to reduce GHG emissions. A sustainable energy system is one in which energy is supplied and converted to energy services in ways that avoid unacceptable consequences for local, regional, and global natural systems that control climate and support ecosystems that provide essential services. Figure 3.1 illustrates typical conversions of a primary energy resource (solar, wind, geothermal energy, fossil or nuclear resources, etc.) into a product, such as a fuel or an energy carrier, like electricity, that then can be converted to a service like heat, light, or mechanical work. Sustainable processes and systems that convert some primary energy resource into energy services will be ones that are as efficient as possible – smaller quantities of the primary energy resource are needed and fewer waste materials are created if the conversions are efficient. Some have argued that only energy flows such as solar, wind, and wave power should be considered sustainable. Others note that any system of energy conversions has some footprint and impact, and that sustainability is necessarily a relative measure, not an absolute one. In any case, sustainable systems will have low impacts over the full life cycle of the conversions (see Chapter 41). Recycling of materials used in energy conversions will be maximized, and amounts of waste materials created in the chain of energy conversions to services will be minimized when the whole cycle from primary resource to services (such as mechanical work) to waste heat and products is considered.
Neuroimaging research has demonstrated medial prefrontal cortex (mPFC) hyporesponsivity and amygdala hyperresponsivity to trauma-related or emotional stimuli in post-traumatic stress disorder (PTSD). Relatively few studies have examined brain responses to the recollection of stressful, but trauma-unrelated, personal events in PTSD. In the current study, we sought to determine whether regional cerebral blood flow (rCBF) abnormalities in mPFC and amygdala in PTSD could be observed during the recollection of trauma-unrelated stressful personal events.
Participants were 35 right-handed male combat veterans (MCVs) and female nurse veterans (FNVs) who served in Vietnam: 17 (seven male, 10 female) with current military-related PTSD and 18 (nine male, nine female) with no current or lifetime PTSD. We used positron emission tomography (PET) and script-driven imagery to study rCBF during the recollection of trauma-unrelated stressful versus neutral and traumatic events.
Voxelwise tests revealed significant between-group differences for the trauma-unrelated stressful versus neutral comparison in mPFC, specifically in the anterior cingulate cortex (ACC). Functional region of interest (ROI) analyses demonstrated that this interaction in mPFC represented greater rCBF decreases in the PTSD group during trauma-unrelated stressful imagery relative to neutral imagery compared to the non-PTSD group. No differential amygdala activation was observed between groups or in either group separately.
Veterans with PTSD, compared to those without PTSD, exhibited decreased rCBF in mPFC during mental imagery of trauma-unrelated stressful personal experiences. Functional neuroanatomical models of PTSD must account for diminished mPFC responses that extend to emotional stimuli, including stressful personal experiences that are not directly related to PTSD.
There is currently no standardised management protocol following functional endoscopic sinus surgery. This study assessed frequent endoscopic cleaning versus minimal intervention in the early post-operative period following such surgery.
The primary outcome measure was ethmoid cavity healing, based on endoscopic appearance, graded using a modified Lund–MacKay endoscopic score.
Secondary outcome measure:
Lund–MacKay symptom score before and after surgery.
There was no overall statistically significant difference between the two groups (p = 0.37). Subgroup analysis revealed a significant effect of regular suction clearance on adhesions at three months (p = 0.048), but not on oedema, polyps, granulation, discharge or crusting.
There is no evidence from this study to support frequent endoscopic cleaning in the early post-operative period after functional endoscopic sinus surgery. Less intensive post-operative management is recommended, resulting in decreased patient morbidity and fewer post-operative follow-up appointments.
The usually more controlled circumstances of airway management in the operating room (OR) often provide better conditions, better monitoring, and more experienced personnel, particularly when a problem occurs, than is available in other critical care environments or the emergency department. While the detection of CO2 by capnography after completion of a difficult intubation procedure may suggest success, it may more precisely indicate only that the tube tip is somewhere in the respiratory path, although perhaps not exactly where the intubationist desires. A capnography pattern indicating declining CO2 in each subsequent breath over several breaths will help identify esophageal intubation. Unilateral pathophysiologic conditions that cause unilateral hypoventilation or high airway resistances would result in a biphasic waveform. Many techniques to facilitate blind nasal tracheal intubation use the detection of significant exhaled gas flow from a spontaneously breathing patient to indicate the proximity of the tube tip to the glottic opening.
Enclosed and semi-enclosed environments, particularly those in extremely isolated and hostile environments, such as outer space and the deep oceans, present unique challenges in terms of maintaining safe working conditions for the individuals exposed to them. The best approach to view the current concern about greenhouse gases is to revisit the past, particularly through ice core analysis, which can yield a record of thousands of years. Many hazardous gases are present in mines, including sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and methane (CH4). The study of completely self-contained and renewable environments was attempted with several closed ecosystem experiments in order to better understand the closed environment of the planet we live on. Monitoring and control systems for these environments are highly complex and specialized to meet unique challenges.
Boron diffusion profiles in single crystal silicon from highly doped polysilicon sources have been measured using SIMS after diffusion at 950°C for various times. These data have been analyzed to determine D(c) of boron in the single crystal. It is ncrmally assumed that at high boron concentrations D increases linearly with concentration. However, the shape of these profiles indicates that for a polysilicon source, this behavior does not appear to hold. Using Bolzmann-Matano analysis, D(c) was found to be insensitive to boron concentrations above 3.0E19 atoms/cm3. The results of this analysis were confirmed by using them as input to a diffusion simulation computer program and excellent agreement with the experimental profiles was obtained. The value of D was found to be unusually high at all concentrations in the single crystal and increased almost linearly with the doping level of the polysilicon. The effect of the furnace ramp-down cycle on the profiles near the crystal surface have also been investigated.
We show that the optical and electrical properties of microcrystalline silicon (μc-Si:H) deposited by the VHF-GD technique at 110 MHz can considerably be tuned by changing the dilution ratio of silane to hydrogen.
With increasing silane dilution we observe enhanced optical absorption for energies below 2 eV due to the transition of the material from amorphous / microcrystalline mixture to a pure microcrystalline phase. Simultaneously, the light scattering and the defect absorption increases. Strong dilution also promotes the incorporation of impurities into the material, leading to a pronounced extrinsic behaviour as seen from the decrease of the activiation energy of the electrical conductivity.
The electrical properties were investigated in the dark by the Time of Flight technique. We measured drift mobilities at room temperature which slightly increase with dilution, reaching values of 3 cm2/Vs for electrons and 1.2 cm2/Vs for holes. The ratio between electron and hole drift mobilities is found to be around 2 for all samples studied, similar to that of crystalline silicon.
Furthermore, post-transient Time of Flight measurements revealed detrimental electron deep traps in low dilution material.