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Introduction: A fundamental hemodynamic parameter, the central venous pressure (CVP) is rarely available in the emergency patient due the delay and risks inherent to central vein cannulation. Recently, two non-invasive strategies have emerged: a) point-of-care ultrasound to supplement traditional inspection the internal jugular waveform ; or b) near-infrared spectroscopy (NIRS) of the external jugular vein. Methods: Five medical students underwent standardized training on both NIRS device (Venus 2000 CVP; Mespere Life Sciences, Waterloo ON) and ultrasound-assisted CVP assessment. During prescheduled, randomly permuted and balanced shifts, a pair of students obtained blinded independent measurements using each device within 10 minutes of each other. High priority subjects likely to have abnormal CVP (e.g. vomiting, dehydrated, heart failure, sepsis) were approached preferentially, followed by a convenience sample of other eligible patients in the emergency department. Secondary outcomes were stopwatch-recorded time from device ready to stable measurement, as well as operator ease, operator confidence and patient discomfort. The blinded treating physician rated each subjects volume status on an ordered scale: depleted, neutral and overloaded. Results: We enrolled 104 patients (median [IQR] age 68 [53, 78] years; 50% male; BMI 27.6 [17.0, 47.7] kg/m2; admission rate 27%) in June-August 2017. Treating physicians classified 17 as volume depleted and 12 overloaded. CVP measurements differed widely between techniques: ultrasound 8 [7, 9] cmH2O (3 cases unobtainable) vs NIRS 12 [8, 17] cmH2O (13 unobtainable). Agreement and correlation between the two devices was extremely low (R2=0.04). While neither technique demonstrated a strong association with the treating physicians estimate of volume status, only the ultrasound values increased monotonically with physician estimate. With regards to secondary outcomes, ultrasound measurements took less time (paired difference 50 seconds [95% CI 7, 93]), and operators were more confident (0.63 [0.02, 1.23] out of 10) and at ease (0.78, [0.13, 1.43]) with ultrasound; patients rated discomfort equally (-0.06 [-0.30, 0.18]). Conclusion: Non-invasive measurement of CVP remains a challenge in the emergency department. The external jugular pressure by NIRS has very high variability and poor agreement with ultrasound-enhanced inspection of the internal jugular, suggesting that this technique is not yet practical for use by non-experts.
Pork and pork products are recognised as vehicles of Salmonella Typhimurium infection in humans. Seaweed-derived polysaccharides (SWE) and galacto-oligosaccharides (GOS) have shown to exhibit antimicrobial, prebiotic and immunomodulatory activity. The objective of this study was to assess the effects of dietary GOS and SWE supplementation on reducing S. Typhimurium numbers and intestinal inflammation in vivo. In total, 30 pigs (n=10/treatment, BW 30.9 kg) were randomly assigned to three dietary treatments: (1) basal diet; (2) basal diet+2.5 g GOS/kg diet; (3) basal diet+SWE (containing 180 mg laminarin/kg diet+340 mg fucoidan/kg diet). Following an 11-day dietary adaptation period, pigs were orally challenged with 108 colony-forming units/ml S. Typhimurium (day 0). Pigs remained on their diets for a further 17 days and were then sacrificed for sample collection. The SWE supplementation did not affect S. Typhimurium numbers on days 2 and 4 post-challenge but reduced S. Typhimurium numbers in faecal samples collected day 7 post-challenge (−0.80 log gene copy numbers (GCN)/g faeces) and in caecal and colonic digesta (−0.62 and −0.98 log GCN/g digesta, respectively; P<0.05) compared with the control treatment. Lactobacillus numbers were increased in caecal and colonic digesta after GOS supplementation (+0.70 and +0.35 log GCN/g digesta, respectively; P<0.05). In colonic tissue, both GOS and SWE supplementation resulted in reduced messenger RNA expression levels of interleukin (IL)-6, IL-22, tumour necrosis factor-α and regenerating islet-derived protein 3-γ (P<0.05). It can be concluded that dietary supplementation of SWE reduced faecal and intestinal S. Typhimurium numbers compared with the basal diet, whereas dietary GOS supplementation increased Lactobacillus numbers in caecal and colonic digesta but did not affect S. Typhimurium numbers. Supplementation of GOS and SWE reduced the gene expression of pro-inflammatory cytokines in colonic tissue of pigs after the experimental S. Typhimurium challenge.
The term “urban revolution” was introduced by Gordon Childe in 1936 to highlight the powerful process of transforming agricultural societies to large complex urban centers. His model describes how communities, beginning around 9000 years ago, grew from tens or hundreds to thousands of people. In 3100 BC, Memphis, Egypt was the largest city in the world with over 30 000 residents. Today, the Cairo metropolitan area has over 17 million inhabitants and ranks 15th on the list of the world’s largest cities. Mega-cities such as Tokyo, Seoul, Mexico City, and New York have over 20 million urban dwellers and continue to grow. The scale and complexity of the urbanization process originally depicted by Childe has little resemblance to what is happening today.
In the short history of humans on our planet, the number, population size, spatial extent, rate of growth, and degree of environmental impact of cities are unprecedented. Today, cities and towns face a myriad of formidable environmental challenges concerning food production, energy, water, waste management, and pollution, as well as social challenges in regard to jobs, poverty, and human health and wellbeing. I propose that as a result of the current rate and magnitude of urbanization around the globe, we are on the cusp of a new “urban revolution.” The goal and rallying call of this revolution is “We Want Healthy, Liveable, Sustainable, and Resilient Cities and Towns.”
Designing is a key component of professional practice in many fields of human endeavor (e.g., architecture, engineering, industrial design, art, and literature). For engineers, designing integrates engineering knowledge, skill, and vision in the pursuit of innovations to solve problems and enable modern life.
With this understanding, engineering educators have, for several decades, been infusing their programs with design curricula and pedagogical experiences in order to enhance the design competencies of engineering graduates. Paralleling the development of these curricula and experiences, a growing body of research has been providing a scholarly basis for engineering design education.
The goal of this chapter is to acquaint readers with engineering design education research and practice. To situate engineering design education in the larger context, we first present a brief history of research on design processes across several fields and then move to a more specific description of research on engineering design processes. We then focus on research that investigates effective ways to teach and assess the design process and review curricular structures and pedagogies that are commonly used in undergraduate engineering programs.
The aim of this study was to retrospectively assess the value of whole genome sequencing (WGS) compared to conventional typing methods in the investigation and control of an outbreak of Shigella sonnei in the Orthodox Jewish (OJ) community in the UK. The genome sequence analysis showed that the strains implicated in the outbreak formed three phylogenetically distinct clusters. One cluster represented cases associated with recent exposure to a single strain, whereas the other two clusters represented related but distinct strains of S. sonnei circulating in the OJ community across the UK. The WGS data challenged the conclusions drawn during the initial outbreak investigation and allowed cases of dysentery to be implicated or ruled out of the outbreak that were previously misclassified. This study showed that the resolution achieved using WGS would have clearly defined the outbreak, thus facilitating the promotion of infection control measures within local schools and the dissemination of a stronger public health message to the community.
A 2 × 2 factorial experiment (n = 12 replicates per treatment, 4 pigs per replicate) was performed to investigate the effects of seaweed extracts, laminarin (derived ß-glucans) and fucoidan (sulphated polysaccharides), independently or in combination on post-weaning piglet performance and selected microbial populations. At weaning, the piglets (24 days of age, 6.4 kg live weight) were assigned to one of the four dietary treatments: (T1) basal diet, (T2) basal diet with 300 p.p.m. laminarin, (T3) basal diet with 240 p.p.m. fucoidan, (T4) basal diet with 300 p.p.m. laminarin and 240 p.p.m. fucoidan. Pigs offered diets supplemented with laminarin had an increased daily gain (P < 0.01), and gain-to-feed ratio (P < 0.05) compared to pigs offered diets without laminarin supplementation during the experimental period (days 0 to 21). Pigs offered laminarin-supplemented diets had an increased faecal dry matter and reduced diarrhoea (P < 0.05) during the critical 7 to 14 day period. Pigs offered diets containing laminarin had reduced faecal Escherichia coli populations. There was a significant interaction (P < 0.01) on faecal Lactobacilli populations between laminarin and fucoidan. Pigs offered the fucoidan diet had an increased Lactobacilli population compared to pigs offered the basal diet. However, there was no effect of fucoidan on faecal Lactobacilli populations when laminarin was added. Overall, the reduction in E. coli population and the increase in daily gain suggest that laminarin may provide a dietary means to improve gut health after weaning.
Comparative studies can be simply described as the systematic assessment of similarities and differences between diverse entities, philosophies and styles. To conduct such studies requires similar data that can be compared and an appropriate method or scheme of comparison. For example, comparisons can range from a simple assessment of the morphological traits of different species of plants to a comparison of the political and economic systems of different cities. Such studies have provided important new understandings about the evolutionary relationships between plants as well as the factors that influence the creation and dynamics of political and economic systems around the world. Comparative studies are a valued and well tested method of developing new understandings in a diversity of subjects and are especially well suited to studies of literature, religion, linguistics, medicine, biology and sociology. In the field of sociology, the comparative approach has been vital to understanding the structure and dynamics of human societies (Bollen et al.,1993). This chapter focuses on the less studied role of comparative studies in understanding the ecology of cities and towns.
In the field of biology, comparative methods have been successfully applied in the traditional subdisciplines of evolution, behaviour and ecology (Gittleman and Luh, 1992) and indeed in new fields such as comparative phylogeography (Bermingham and Moritz, 1998). Comparative studies of plant and animal traits have provided the foundations for the well developed classification and phylogenic systems currently used to understand the taxonomic and phylogenic relationships between organisms.
This chapter addresses the conceptual frameworks that have been used in urban ecological studies in two US metropolises, and the theoretical challenges for urban ecology that flow from these experiences. The two topics relate well because frameworks lay out the structure of knowledge in a subject area, and the theoretical assessment addresses the applicability of frameworks beyond the two cities used here. The frameworks began to be articulated with the establishment of the Urban–Rural Gradient Ecology (URGE) programme in the New York City metropolitan region in the early 1980s (McDonnell and Pickett,1990). That programme continued until the relocation of its leader, Mark McDonnell, to Australia in 1998.
Although the urban–rural gradient framework has been effective in studying the biological components of human-dominated ecosystems, there has been an increasing call to better integrate the biological, physical and socio-economic components of urban systems (Niemelä et al., 2000; Grimm et al., 2000; Collins et al., 2000; Pickett et al., 2001; Alberti et al., 2003). In the Baltimore Ecosystem Study, a Long-Term Ecological Research project (LTER) funded by the National Science Foundation, which is part of a network of 26 long-term studies in various ecosystem types located throughout North America and its territories (http://www.lternet.edu), the urban–rural gradient framework has been extended to include social sciences (Grimm et al., 2000). Because the Baltimore Ecosystem Study (BES) builds closely upon the New York URGE study, they encompass a wide range of approaches to urban ecological studies and present an excellent opportunity to examine conceptual frameworks that can be used to promote and integrate urban ecological studies.
The growth of cities and towns together with the associated increase in their ecological ‘footprint’ is one of the most serious ecological problems facing the world today. The increase in the number of people living in cities and towns, coupled with the magnitude and intensity of human activities, has resulted in what Likens (1991) refers to as human-accelerated environmental change. This includes changes in land use, toxification of the biosphere, invasion of exotic species and loss of biotic diversity. These changes are most evident in major cities, but significant changes are also occurring in peri-urban areas, in small towns and especially in coastal settlements. The rate of change associated with the expansion and creation of cities and towns is particularly high in developing countries (Lee, 2007). Human-accelerated environmental change is occurring at small and large spatial scales throughout the world, but the true magnitude of the impact of these changes is difficult to envisage because of uncertainties in the predicted effects of global climate change (IPCC, 2001).
We face many challenges and potential conflicts if we are to manage current day-to-day problems and attempt the bigger task of creating sustainable cities and towns in the future. Although cities and towns are dominated by human-built structures and activities (buildings, vehicles, impermeable surfaces, parks, etc.), they are functioning ecosystems that possess many of the same components (plants, animals, water, soil, etc.) and processes (i.e. nutrient and water cycling) as less human-dominated natural systems (McDonnell and Pickett, 1993b; Grimm et al., 2003).
The unprecedented growth of cities and towns around the world, coupled with the unknown effects of global change, has created an urgent need to increase ecological understanding of human settlements, in order to develop inhabitable, sustainable cities and towns in the future. Although there is a wealth of knowledge regarding the understanding of human organisation and behaviour, there is comparably little information available regarding the ecology of cities and towns. This book brings together leading scientists, landscape designers and planners from developed and developing countries around the world, to explore how urban ecological research has been undertaken to date, what has been learnt, where there are gaps in knowledge, and what the future challenges and opportunities are.
Calls to study the ecology of urban areas were first made in the early twentieth century by both social scientists and traditional ecologists (i.e. plant and animal ecologists) (Adams, 1935, 1938). Some 40 years later, the Ecological Society of Australia held a symposium and published a follow-up book entitled The City as a Life System (Nix, 1972) which aimed to stimulate public and professional interest in the ecology of cities. At about the same time, a workshop was convened in the USA by The Institute of Ecology (TIE), now defunct, which brought together ecologists from a diversity of disciplines to identify national and regional urban needs. The proceedings of this workshop were published in a book entitled The Urban Ecosystem: A Holistic Approach (Stearns and Montag, 1974). Unfortunately, these books were not widely distributed and thus these early workshop efforts did not stimulate new North American or Australian ecological studies of human settlements. In contrast, European and some Australasian researchers have embraced the ecological study of urban ecosystems for over 30 years (e.g. Numata, 1976, 1977; Newcombe et al., 1978; Boyden et al., 1981; Bornkamm et al., 1982; Natuhara and Imai, 1996, 1999; Breuste et al., 1998; Sukopp, 1998, 2002).