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Ices of various compositions and in various phases and combinations with one another are found on planetary surfaces through remote sensing techniques, of which optical spectroscopy is the most powerful and diagnostic. Ices also are found in combination with minerals and organic materials; some complex organic materials are the result of energetic processing of ices, while some may represent organic matter from other sources. Remote spectroscopic observations from Earth-based telescopes and planetary probes are usually interpreted with the aid of radiative transfer models that account for the compositions, particle properties, mixing configurations and other parameters relevant to the materials under consideration. This chapter reviews the spectroscopic character of planetary ices in pure states and in combinations with one another, and with minerals and organic solid materials found by remote sensing techniques and by the analysis of analog materials, both naturally occurring and synthesized in the laboratory and thus available for analytical studies.
The Cassini Visual Infrared Mapping Spectrometer (VIMS) spans a wavelength range of 0.34 to 5.2 µm. Executing numerous close targeted flybys of the major moons of Saturn, as well as serendipitous flybys of the smaller moons, VIMS gathered millions of spectra of these bodies during its 13-year mission, some at spatial resolutions of a few hundred meters. The surfaces of the inner moons are dominated by water ice, while Iapetus, Hyperion, and Titan have substantial amounts of dark materials, including hydrocarbons, on their surfaces. Phoebe is grayer in color in the visible than Saturn’s other low-albedo moons. The surfaces of the inner small moons are also dominated by water ice, and they share compositional similarities to the main rings. The optical properties of the main moons are affected by particles from Saturn’s rings: the inner moons are coated by the E-ring, which originates from cryoactivity on Enceladus, while Iapetus and Hyperion are coated by particles from the Phoebe ring. Cassini VIMS detected previously unknown volatiles and organics on these moons, including CO2, H2, organic molecules as complex as aromatic hydrocarbons, nano-iron, and nano-iron oxides.
A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar.
This paper presents a comprehensive analytical approach to the modelling of wall-pressure fluctuations under a turbulent boundary layer, unifying and expanding the analytical models that have been proposed over many decades. The Poisson equation governing pressure fluctuations is Fourier transformed in the wavenumber domain to obtain a modified Helmholtz equation, which is solved with a Green’s function technique. The source term of the differential equations is composed of turbulence–mean shear and turbulence–turbulence interaction terms, which are modelled separately within the hypothesis of a joint normal probability distribution of the turbulent field. The functional expression of the turbulence statistics is shown to be the most critical point for a correct representation of the wall-pressure spectrum. The effect of various assumptions on the shape of the longitudinal correlation function of turbulence is assessed in the first place with purely analytical considerations using an idealised flow model. Then, the effect of the hypothesis on the spectral distribution of boundary-layer turbulence on the resulting wall-pressure spectrum is compared with the results of direct numerical simulation computations and pressure measurements on a controlled-diffusion aerofoil. The boundary layer developing over the suction side of this aerofoil in test conditions is characterised by an adverse pressure gradient. The final part of the paper discusses the numerical aspect of wall-pressure spectrum computation. A Monte Carlo technique is used for a fast evaluation of the multi-dimensional integral formulation developed in the theoretical part.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Leishmania rely heavily on glycans to complete their digenetic life cycle in both mammalian and phlebotomine sand fly hosts. Leishmania promastigotes secrete a proteophosphoglycan-rich gel (Promastigote Secretory Gel, PSG) that is regurgitated during transmission and can exacerbate infection in the skin. Here we explored the role of PSG from natural Leishmania-sand fly vector combinations by obtaining PSG from Leishmania (L.) major-infected Phlebotomus (P.) papatasi and P. duboscqi and L. tropica-infected P. arabicus. We found that, in addition to the vector's saliva, the PSG from L. major and L. tropica potently exacerbated cutaneous infection in BALB/c mice, improved the probability of developing a patent cutaneous lesion, parasite growth and the evolution of the lesion. Of note, the presence of PSG in the inoculum more than halved the prepatent period of cutaneous L. tropica infection from an average of 32 weeks to 13 weeks. In addition, L. major and L. tropica PSG extracted from the permissive experimental vector, Lutzomyia (Lu.) longipalpis, also exacerbated infections in mice. These results reinforce and extend the hypothesis that PSG is an important and evolutionarily conserved component of Leishmania infection that can be used to facilitate experimental infection for drug and vaccine screening.
Introduction: Although oral rehydration therapy is recommended for children with acute gastroenteritis (AGE) with none to some dehydration, intravenous (IV) rehydration is still commonly administered to these children in high-income countries. IV rehydration is associated with pain, anxiety, and emergency department (ED) revisits in children with AGE. A better understanding of the factors associated with IV rehydration is needed to inform knowledge translation strategies. Methods: This was a planned secondary analysis of the Pediatric Emergency Research Canada (PERC) and Pediatric Emergency Care Applied Research Network (PECARN) randomized, controlled trials of oral probiotics in children with AGE-associated diarrhea. Eligible children were aged 3-48 months and reported > 3 watery stools in a 24-hour period. The primary outcome was administration of IV rehydration at the index ED visit. We used mixed-effects logistic regression model to explore univariable and multivariable relationships between IV rehydration and a priori risk factors. Results: From the parent study sample of 1848 participants, 1846 had data available for analysis: mean (SD) age of 19.1 ± 11.4 months, 45.4% females. 70.2% (1292/1840) vomited within 24 hours of the index ED visit and 34.1% (629/1846) received ondansetron in the ED. 13.0% (240/1846) were administered IV rehydration at the index ED visit, and 3.6% (67/1842) were hospitalized. Multivariable predictors of IV rehydration were Clinical Dehydration Scale (CDS) score [compared to none: mild to moderate (OR: 8.1, CI: 5.5-11.8); severe (OR: 45.9, 95% CI: 20.1-104.7), P < 0.001], ondansetron in the ED (OR: 1.8, CI: 1.2-2.6, P = 0.003), previous healthcare visit for the same illness [compared to no prior visit: prior visit with no IV (OR: 1.9, 95% CI: 1.3-2.9); prior visit with IV (OR: 10.5, 95% CI: 3.2-34.8), P < 0.001], and country [compared to Canada: US (OR: 4.1, CI: 2.3-7.4, P < 0.001]. Significantly more participants returned to the ED with symptoms of AGE within 3 days if IV fluids were administered at the index visit [30/224 (13.4%) versus 88/1453 (6.1%), P < 0.001]. Conclusion: Higher CDS scores, antiemetic use, previous healthcare visits and country were independent predictors of IV rehydration which was also associated with increased ED revisits. Knowledge translation focused on optimizing the use of antiemetics (i.e. for those with dehydration) and reducing the geographic variation in IV rehydration use may improve the ED experience and reduce ED-revisits.
The goal of this study was to determine physician performance in diagnosis and management of postpartum depression (PPD) and to provide needed education in the consequence free environment of a virtual patient simulation (VPS).
∙ A continuing medical education activity was delivered via an online VPS learning platform that offers a lifelike clinical care experience with complete freedom of choice in clinical decision-making and expert personalized feedback to address learner’s practice gaps
∙ Physicians including psychiatrists, primary care physicians (PCPs), and obstetricians/gynecologists (ob/gyns) were presented with two cases of PPD designed to model the experience of actual practice by including use of electronic health records
∙ Following virtual interactions with patients, physicians were asked to make decisions regarding assessments, diagnoses, and pharmacologic therapies. The clinical decisions were analyzed using a sophisticated decision engine, and clinical guidance (CG) based on current evidence-based recommendations was provided in response to learners’ clinical decisions
∙ Impact of the education was measured by comparing participant decisions pre- and post-CG using a 2-tailed, paired t-test; P <.05 was considered statistically significant
∙ The activity launched on Medscape Education on April 26, 2018, and data were collected through to June 17,2018.
∙ From pre- to post-CG in the simulation, physicians were more likely to make evidence-based clinical decisions related to:
∙ Ordering appropriate baseline tests including tools/scales to screen for PPD: in case 1, psychiatrists (n=624) improved from 34% to 42% on average (P<.05); PCPs (n=197) improved from 38% to 48% on average (P<.05); and, ob/gyns (n=216) improved from 30% to 38% on average (P<.05)
∙ Diagnosing moderate-to-severe PPD: in case 2, psychiatrists (n=531) improved from 46% to 62% (P<.05); PCPs (n=154) improved from 43% to 55% (P<.05); and, ob/gyns (n=137) improved from 55% to 73% (P<.05)
∙ Ordering appropriate treatments for moderate-to-severe PPD such as selective serotonin-reuptake inhibitors: in case 2, psychiatrists (n=531) improved from 47% CG to 75% (P<.05); PCPs (n=154) improved from 55% to 74% (P<.05); and, ob/gyns (n=137) improved from 51% to 78% (P<.05)
∙ Interestingly, a small percentage of physicians (average of 5%) chose investigational agents for PPD which were in clinical trials pre-CG, and this increased to an average of 9% post-CG
Physicians who participated in VPS-based education significantly improved their clinical decision-making in PPD, particularly in selection of validated screening tools/scales, diagnosis, and pharmacologic treatments based on severity. Given that VPS immerses physicians in an authentic, practical learning experience matching the scope of clinical practice, this type of intervention can be used to determine clinical practice gaps and translate knowledge into practice.
Funding Acknowledgements: The educational activity and outcomes measurement were funded through an independent educational grant from Sage Therapeutics, Inc.
Chondrules contain ferromagnetic minerals that may retain a record of the magnetic field environments in which they cooled. Paleomagnetic experiments on separated chondrules can potentially reveal the presence of remanent magnetization from the time of chondrule formation. The existence of such a magnetization places quantitative bounds on the frequency of interchondrule collisions, while the intensity of magnetization may be used to infer the strength of nebular magnetic fields and thereby constrain the mechanism of chondrule formation. Recent advances in laboratory instrumentation and techniques have permitted the isolation of nebular remanent magnetization in chondrules, providing the potential basis to probe the formation environments of chondrules from a range of chondrite classes.
Lower prenatal exposure to n-3 PUFA relative to n-6 PUFA has been hypothesised to influence allergy development, but evidence remains largely inconsistent. In the Dutch Maastricht Essential Fatty Acid Birth (MEFAB) (n 293) and Greek RHEA Mother–Child (n 213) cohorts, we investigated whether cord blood phospholipid PUFA concentrations are associated with symptoms of wheeze, asthma, rhinitis and eczema at the age of 6–7 years. Information on allergy-related phenotypes was collected using validated questionnaires. We estimated relative risks (RR) and 95 % CI for associations of PUFA with child outcomes using multivariable generalised linear regression models. In pooled analyses, higher concentration of the n-3 long-chain EPA and DHA and a higher total n-3:n-6 PUFA ratio were associated with lower risk of current wheeze (RR 0·61; 95 % CI 0·45, 0·82 per sd increase in EPA+DHA and 0·54; 95 % CI 0·39, 0·75 per unit increase in the n-3:n-6 ratio) and reduced asthma risk (RR 0·50; 95 % CI 0·31, 0·79 for EPA+DHA and 0·43; 95 % CI 0·26, 0·70 for the n-3:n-6 ratio). No associations were observed for other allergy-related phenotypes. The results were similar across cohorts. In conclusion, higher EPA and DHA concentrations and a higher n-3:n-6 fatty acid ratio at birth were associated with lower risk of child wheeze and asthma. Our findings suggest that dietary interventions resulting in a marked increase in the n-3:n-6 PUFA ratio, and mainly in n-3 long-chain PUFA intake in late gestation, may reduce the risk of asthma symptoms in mid-childhood.
In this review, we examine how structural priming has been used to investigate the representation of first and second language syntactic structures in bilinguals. Most experiments suggest that structures that are identical in the first and second language have a single, shared mental representation. The results from structures that are similar but not fully identical are less clear, but they may be explained by assuming that first and second language representations are merely connected rather than fully shared. Some research has also used structural priming to investigate the representation of cognate words. We will also consider whether cross-linguistic structural priming taps into long-term implicit learning effects. Finally, we discuss recent research that has investigated how second language syntactic representations develop as learners’ proficiency increases.
This talk commented on our progress in understanding high Ė pulsar output, with the photon power dominated by GeV radiation and the total power dominated by the e±/B wind. We are increasingly appreciating the anisotropy in these outflows, with high energy pulsar beaming probed by the distribution of γ-ray pulse profiles and wind anisotropy mapped by synchrotron images of PWNe. Possible hemispheric asymmetry and the prospects for additional probes of pulsar spindown, particularly from compact binaries in the black widow class, are briefly mentioned.
Introduction/Innovation Concept: Student Run Simulation Team (SRST) is an extracurricular medical student group that provided peers with opportunities to learn and teach principles of acute care medicine in a simulated environment. Early exposure to simulation has been identified as a way for medical students to engage in self-directed education. SRST operated through a peer-led model. Senior medical students designed and delivered didactic sessions, simulation scenarios, and debriefed the scenarios to emphasise targeted objectives. Methods: Informal interviews conducted by the SRST as part of a needs analysis identified barriers to an effective transition from pre-clerkship to clerkship. Specifically, principles of team dynamics including effective communication and role clarification in emergency situations were identified as areas where students lacked confidence. The curriculum focused on leadership and an effective team approach to common acute presentations. SRST members acquired simulation skills under the guidance of a simulation team at the University of Calgary. In the inaugural year, 8 second year students developed and delivered the curriculum to 16 first year students. Quality improvement surveys and participant feedback contributed to ongoing program review and refinement. Curriculum, Tool, or Material: Didactic lectures and task-trainer based skills sessions were created to assist the medical students in developing a foundational approach to a patient presenting to the emergency department. Three distinct simulations of increasing complexity were designed for students to build on their skills. SRST members worked with simulation consultants during 4 custom designed training sessions to develop simulation skills (design and debriefing). The distinguishing aspect of SRST is an emphasis on the non-technical skills of teamwork, leadership, and communication, rather than knowledge acquisition alone. The structure also included a succession plan for continued peer-led education where the student participants will form the next year’s team and will receive similar simulation education. Conclusion: SRST is the first student-run simulation initiative to be established in a Canadian medical school. This near-peer team allowed for early practice of non-technical skills in emergency settings. SRST facilitated opportunities for simulation education for both the junior students as participants, and the senior medical students as educators. This is an ongoing initiative, with plans to continue program development in future years.
Introduction: Fast track (FT) implementation in emergency departments (ED) has shown a decrease in patient wait times, length of stay (LOS), left without being seen rates, and has increased patient satisfaction. The objective of this study was to analyze the demographics and presenting complaints of patients presenting to FT in Calgary EDs using local administrative databases to understand the current selection of FT patients, as well as to uncover potential throughput efficiencies through LOS analysis. Methods: Sunrise Clinical Manager data was pulled from the Foothills Medical Center (FMC), Peter Lougheed Center (PLC), and Rockyview General Hospital (RGH) EDs between October 2015 and September 2016. Based on consensus achieved by the Calgary FT-Minor Treatment Sub-committee, data was descriptively analyzed based on the following criteria: (1) triage profiles of the Calgary ED sites; (2) site admission rates by complaint, Canadian Triage and Acuity Scale (CTAS), vitals, and age; (3) LOS for orthopedic patients admitted from FT/Minor; and, (4) LOS in FT for non-admitted back pain patients. Results: A total of 53911 patients were triaged to FT, with 16224 patients triaged to FMC, 18299 to PLC, and 19388 to RGH. 6.9% of FT patients were admitted to hospital at FMC, 4.8% at PLC and 4.8% at RGH. 14.4% of patients at FMC, 18.3% at PLC and 17.6% at RGH were CTAS 2; 40.9% of patients at FMC, 46.2% at PLC and 37.9% at RGH were CTAS 3; 34.0% of patients at FMC, 27.8% at PLC and 33.3% at RGH were CTAS 4; 10.7% of patients at FMC, 7.7% from PLC and 11.2% for RGH were CTAS 5. For FT patients 80 years or older, 10.4% were admitted at FMC, 13.1% at PLC and 9.4% at RGH. The top FT presenting complaints at all sites were lower extremity injury, upper extremity injury, and laceration/puncture. The annual FT bed hours for patients admitted to orthopedic surgery (consultation request to time of orthopedic admission) was 802.3 hours at FMC, 441.1 PLC and 705.1 from RGH. The annual FT bed hours for patients with non-admitted back pain (FT bed to time of discharge) was 2144.3 hours from FMC, 3367.9 from PLC and 1134.9 from RGH. Conclusion: The efficiency of FT is based on streamlining low acuity patients with an expected rapid discharge from hospital. The results of this investigation will be presented to the FT-Minor Treatment Sub-committee in order to utilize current admission rates, patient profiles, and aggregate LOS to potentially improve throughput.
The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.
The Learning Health System Network clinical data research network includes academic medical centers, health-care systems, public health departments, and health plans, and is designed to facilitate outcomes research, pragmatic trials, comparative effectiveness research, and evaluation of population health interventions.
The Learning Health System Network is 1 of 13 clinical data research networks assembled to create, in partnership with 20 patient-powered research networks, a National Patient-Centered Clinical Research Network.
Results and Conclusions
Herein, we describe the Learning Health System Network as an emerging resource for translational research, providing details on the governance and organizational structure of the network, the key milestones of the current funding period, and challenges and opportunities for collaborative science leveraging the network.