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We agree that combining rational analysis with cognitive bounds, what we previously introduced as Cognitively Bounded Rational Analysis, is a promising and under-used methodology in psychology. We further situate the framework in the literature, and highlight the important issue of a theory of subjective utility, which is not addressed sufficiently clearly in the framework or related previous work.
Heat is the most ubiquitous form of energy on planet Earth. Every day, the sun continuously strikes the Earth’s surface with 120,000 Terawatts of energy. This solar energy is more than 10,000 times the amount of energy produced worldwide. With the scarcity of fossil fuels looming on the horizon and its adverse effect on the environment many researchers, from academia to industry, are exploring cleaner, greener and more efficient renewable energy technologies. Thermoelectricity can provide an alternative to hazardous fossil fuels as its electricity is produced directly from heat with no moving parts or working fluid. The efficiency of any thermoelectric material is given by a quantity called the figure of merit ZT. For thermoelectric (TE) devices to be competitive with fluid-based and other energy related devices, ZT greater than 2 is usually sought. Here, we report on the fabrication of thin film thermoelectric materials based on Bi2Te3/WS2 superlattice layer structure using RF magnetron sputtering deposition method. Quantum confinement in these low dimensional and ultrathin superlattices can enhance the density of states near the fermi level resulting in higher ZT value. The thermoelectric figure of merit can be enhanced by controlling the layer thickness close to the phonons mean free path. This way heat carrying phonons with different wavelengths can be scattered efficiently resulting in lower lattice thermal conductivity.
A key task of the team leader in a medical emergency is effective information gathering. Studying information gathering patterns is readily accomplished with the use of gaze-tracking glasses. This technology was used to generate hypotheses about the relationship between performance scores and expert-hypothesized visual areas of interest in residents across scenarios in simulated medical resuscitation examinations.
Emergency medicine residents wore gaze-tracking glasses during two simulation-based examinations (n=29 and 13 respectively). Blinded experts assessed video-recorded performances using a simulation performance assessment tool that has validity evidence in this context. The relationships between gaze patterns and performance scores were analyzed and potential hypotheses generated. Four scenarios were assessed in this study: diabetic ketoacidosis, bradycardia secondary to beta-blocker overdose, ruptured abdominal aortic aneurysm and metabolic acidosis caused by antifreeze ingestion.
Specific gaze patterns were correlated with objective performance. High performers were more likely to fixate on task-relevant stimuli and appropriately ignore task-irrelevant stimuli compared with lower performers. For example, shorter latency to fixation on the vital signs in a case of diabetic ketoacidosis was positively correlated with performance (r=0.70, p<0.05). Conversely, total time spent fixating on lab values in a case of ruptured abdominal aortic aneurysm was negatively correlated with performance (r= −0.50, p<0.05).
There are differences between the visual patterns of high and low-performing residents. These findings may allow for better characterization of expertise development in resuscitation medicine and provide a framework for future study of visual behaviours in resuscitation cases.
Understanding the removal of energy from turbulent fluctuations in a magnetized plasma and the consequent energization of the constituent plasma particles is a major goal of heliophysics and astrophysics. Previous work has shown that nonlinear interactions among counterpropagating Alfvén waves – or Alfvén wave collisions – are the fundamental building block of astrophysical plasma turbulence and naturally generate current sheets in the strongly nonlinear limit. A nonlinear gyrokinetic simulation of a strong Alfvén wave collision is used to examine the damping of the electromagnetic fluctuations and the associated energization of particles that occurs in self-consistently generated current sheets. A simple model explains the flow of energy due to the collisionless damping and the associated particle energization, as well as the subsequent thermalization of the particle energy by collisions. The net particle energization by the parallel electric field is shown to be spatially localized, and the nonlinear evolution is essential in enabling spatial non-uniformity. Using the recently developed field–particle correlation technique, we show that particles resonant with the Alfvén waves in the simulation dominate the energy transfer, demonstrating conclusively that Landau damping plays a key role in the spatially localized damping of the electromagnetic fluctuations and consequent energization of the particles in this strongly nonlinear simulation.
We argue that a radically increased emphasis on (bounded) optimality can contribute to cognitive science by supporting prediction. Bounded optimality (computational rationality), an idea that borrowed from artificial intelligence, supports a priori behavioral prediction from constrained generative models of cognition. Bounded optimality thereby addresses serious failings with the logic and testing of descriptive models of perception and action.
Survival into adult life in patients with aortic coarctation is typical following surgical and catheter-based techniques to relieve obstruction. Late sequelae are recognised, including stroke, hypertension, and intracerebral aneurysm formation, with the underlying mechanisms being unclear. We hypothesised that patients with a history of aortic coarctation may have abnormalities of cerebral blood flow compared with controls.
Patients with a history of aortic coarctation underwent assessment of cerebral vascular function. Vascular responsiveness of intracranial vessels to hypercapnia and degree of cerebral artery stiffness using Doppler-derived pulsatility indices were used. Response to photic stimuli was used to assess neurovascular coupling, which reflects endothelial function in response to neuronal activation. Patient results were compared with age- and sex-matched controls.
A total of 13 adult patients (males=10; 77%) along with 13 controls underwent evaluation. The mean age was 36.1±3.7 years in the patient group. Patients with a background of aortic coarctation were noted to have increased pulse pressure on blood pressure assessment at baseline with increased intracranial artery stiffness compared with controls. Patients with a history of aortic coarctation had less reactive cerebral vasculature to hypercapnic stimuli and impaired neurovascular coupling compared with controls.
Adult patients with aortic coarctation had increased intracranial artery stiffness compared with controls, in addition to cerebral vasculature showing less responsiveness to hypercapnic and photic stimuli. Further studies are required to assess the aetiology and consequences of these documented abnormalities in cerebral blood flow in terms of stroke risk, cerebral aneurysm formation, and cognitive dysfunction.
Simulation-based education (SBE) is an important training strategy in emergency medicine (EM) postgraduate programs. This study sought to characterize the use of simulation in FRCPC-EM residency programs across Canada.
A national survey was administered to residents and knowledgeable program representatives (PRs) at all Canadian FRCPC-EM programs. Survey question themes included simulation program characteristics, the frequency of resident participation, the location and administration of SBE, institutional barriers, interprofessional involvement, content, assessment strategies, and attitudes about SBE.
Resident and PR response rates were 63% (203/321) and 100% (16/16), respectively. Residents reported a median of 20 (range 0–150) hours of annual simulation training, with 52% of residents indicating that the time dedicated to simulation training met their needs. PRs reported the frequency of SBE sessions ranging from weekly to every 6 months, with 15 (94%) programs having an established simulation curriculum. Two (13%) of the programs used simulation for resident assessment, although 15 (94%) of PRs indicated that they would be comfortable with simulation-based assessment. The most common PR-identified barriers to administering simulation were a lack of protected faculty time (75%) and a lack of faculty experience with simulation (56%). Interprofessional involvement in simulation was strongly valued by both residents and PRs.
SBE is frequently used by Canadian FRCPC-EM residency programs. However, there exists considerable variability in the structure, frequency, and timing of simulation-based activities. As programs transition to competency-based medical education, national organizations and collaborations should consider the variability in how SBE is administered.
William “Billy” Mitchell was an early military aviator whose 1925 court-martial caught the imagination of the American public. Born into a family of wealth and political influence, Mitchell nonetheless joined the military at the age of eighteen, distinguishing himself first during the Spanish–American War and, twenty years later, during the First World War, where he rose to the rank of Chief of the Air Service for the U.S. Army. During the early 1920s, Mitchell tirelessly advocated for the primacy of aviation in America's post-war military plans. He argued that airplanes would quickly become the primary military instruments of warfare, and that the nation would best be served by investing heavily in the design and manufacture of specialized aircraft. In order to demonstrate his ideas, he organized a series of high-profile tests and exhibitions, becoming a media darling and nationally famous in the process. He also made numerous enemies, particularly in the Navy, and was eventually court-martialed in what, at the time, was considered to be one of the most noteworthy trials in American history. He was forced out of the Armed Services and died, embittered, a few years prior to the start of the Second World War, a conflict that would prove nearly all of his theories to be sound and his prognostications correct.
Although in no way explicitly acknowledged, the central character in Task Force (1949), a film written and directed by Delmer Daves, espouses nearly all of Mitchell's core theories. This chapter examines the film's fictionalized treatment of a real-life figure, exploring the manner in which Mitchell is valorized—in that the film's central character advances the General's strategic arguments—while simultaneously being erased from history. As Task Force carries the narrative into the Second World War it showcases a heroic figure instead of a tragic one, situating the character at the crossroads of developing philosophies and missed opportunities in American interwar imperialism. Daves the director will also be examined, particularly for the cinematic qualities that suggest it is time to critically re-examine some of his forgotten films, such as Task Force. Finally, Daves’ treatment will be put in context with other aviation films from the same era, most notably Otto Preminger's The Court Martial of Billy Mitchell (1955), which, coming six years later, was able to openly examine the controversial figure.
Sarcocystis neurona is an apicomplexan parasite that causes severe neurological disease in horses and marine mammals. The Apicomplexa are all obligate intracellular parasites that lack purine biosynthesis pathways and rely on the host cell for their purine requirements. Hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) and adenosine kinase (AK) are key enzymes that function in two complementary purine salvage pathways in apicomplexans. Bioinformatic searches of the S. neurona genome revealed genes encoding HXGPRT, AK and all of the major purine salvage enzymes except purine nucleoside phosphorylase. Wild-type S. neurona were able to grow in the presence of mycophenolic acid (MPA) but were inhibited by 6-thioxanthine (6-TX), suggesting that the pathways involving either HXGPRT or AK are functional in this parasite. Prior work with Toxoplasma gondii demonstrated the utility of HXGPRT as a positive-negative selection marker. To enable the use of HXGPRT in S. neurona, the SnHXGPRT gene sequence was determined and a gene-targeting plasmid was transfected into S. neurona. SnHXGPRT-deficient mutants were selected with 6-TX, and single-cell clones were obtained. These Sn∆HXG parasites were susceptible to MPA and could be complemented using the heterologous T. gondii HXGPRT gene. In summary, S. neurona possesses both purine salvage pathways described in apicomplexans, thus allowing the use of HXGPRT as a positive-negative drug selection marker in this parasite.
The diversity of terms and meanings relating to housing with services for older people confounds systematic analysis, especially in international comparative research. This paper presents an analysis of over 90 terms identified in literature from the United Kingdom, the United States of America, Canada, Australia and New Zealand reporting types of housing with services under the umbrella of ‘service integrated housing’ (SIH), defined as all forms of accommodation built specifically for older people in which the housing provider takes responsibility for delivery of one or more types of support and care services. A small number of generic terms covering housing for people in later life, home and community care, and institutional care are reviewed first to define the scope of SIH. Review of the remainder identifies different terms applied to similar types of SIH, similar terms applied to different types, and different terms that distinguish different types. Terms are grouped into those covering SIH focused on lifestyle and recreation, those offering only support services, and those offering care as well as support. Considerable commonality is found in underlying forms of SIH, and common themes emerge in discussion of drivers of growth and diversification, formal policies and programmes, and symbolic meanings. In establishing more commonality than difference, clarification of terminology advances policy debate, programme development, research and knowledge transfer within and between countries.
Calcium phosphates form a vast family of biominerals, which have attracted much attention in fields like biology, medicine, and materials science, to name a few. Solid state Nuclear Magnetic Resonance (NMR) is one of the few techniques capable of providing information about their structure at the atomic level. Here, examples of recent advances of solid state NMR techniques are given to demonstrate their suitability to characterize in detail synthetic and biological calcium phosphates. Examples of high-resolution 31P, 1H (and 17O), solid state NMR experiments of a 17O-enriched monocalcium phosphate monohydrate-monetite mixture and of a mouse tooth are presented. In both cases, the advantage of performing fast Magic Angle Spinning NMR experiments at high magnetic fields is emphasized, notably because it allows very small volumes of sample to be analyzed.
The dopamine hypothesis has been the major pathophysiological theory of
psychosis in recent decades. Molecular imaging studies have provided
in vivo evidence of increased dopamine synaptic
availability and increased presynaptic dopamine synthesis in the striata of
people with psychotic illnesses. These studies support the predictions of
the dopamine hypothesis, but it remains to be determined whether
dopaminergic abnormalities pre-date or are secondary to the development of
psychosis. We selectively review the molecular imaging studies of the
striatal dopaminergic system in psychosis and link this to models of
psychosis and the functional subdivisions of the striatum to make
predictions for the dopaminergic system in the prodromal phase of
In a benthic mesocosm experiment, the effects of two species of burrowing Thalassinidean shrimps (Callianassa subterranea and Upogebia deltaura) on rates of sediment denitrification were determined using the isotope pairing technique. Denitrification rate (Dtot) and coupled nitrification–denitrification (Dn) were shown to be significantly enhanced by the presence of U. deltaura by 2·9 and 3·3 times respectively, relative to control measurements. For U. deltaura the stimulation of the denitrification rate was found to be significantly related to the size of the animal (F=5·81, P=0·042). No deviation from the rates determined in control cores for either Dtot or Dn was observed for those cores inhabited by C. subterranea. The increase in Dtot with U. deltaura was considered to be the result of a combination of different factors, including; the direct extension of the sediment–water interface and an increase in oxygenation of the sediments and solute transport, as a result of the ventilating activities of the animal itself.
Micromechanical structures designed for material characterization through analysis of their nonlinear dynamic response are presented. The structures consist of a rigid movable mass supported by beams which are attached to the wafer substrate. The structures are designed so that they are geometrically constrained, which is the source of their nonlinearity. The nonlinearity is shown to be well modeled by Duffing's equation for a stiffening spring and it is this model which is used to fit the test data to the desired mechanical properties, namely Young's modulus, intrinsic stress and damping.