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Background: With advancements in technology, the use of video as a pedagogical method in medical education has gained in popularity, and may aid in teaching clinical skills. In the UBC MD program, videos have been used to assist in teaching the -neurological exam for several decades, but the currently available videos are outdated and not of contemporary quality. Methods: Drawing upon the cognitive theory of multimedia learning from Mayer and Moreno (2003) which describes methods to maximize learning by minimizing cognitive load, we developed a tool to systematically assess pedagogical videos. We inventoried twelve existing neurology videos and analyzed their use of methods such as weeding (removing extraneous information), signalling (visually highlighting important information), and chunking (grouping similar information together). Results: Generally, older videos had poor audiovisual quality that introduced extraneous load, while more current videos had higher production value, albeit inconsistent with the depth of their content. We therefore produced a new three-part neurological exam video series. We wrote storyboards, filmed with a focus on visually depicting the exam and findings, and edited to elucidate relevant physiological concepts. Conclusions: The end product has been adopted by the UBC MD program, and can be shared with other programs who may wish to adopt them.
To determine the prevalence and factors associated with stunting in 6-month-old South African infants.
This cross-sectional study was part of the baseline of a randomized controlled trial. Weight-for-length, length-for-age and weight-for-age Z-scores were based on the WHO classification. Blood samples were analysed for Hb, plasma ferritin and soluble transferrin receptor (sTfR). Socio-economic, breast-feeding and complementary feeding practices were assessed by questionnaire.
Infants aged 6 months (n 750) from a peri-urban area of Matlosana Municipality, North West Province of South Africa.
Stunting, underweight, wasting and overweight affected 28·5, 11·1, 1·7 and 10·1 % of infants, respectively. Exclusive breast-feeding to 6 months of age was reported in 5·9 % of the infants. Multivariable binary logistic regression showed that birth weight (OR=0·12; 95 % CI 0·07, 0·21, P<0·001) and maternal height (OR=0·94; 95 % CI 0·91, 0·98, P=0·001) were inversely associated with stunting; while male sex (OR=1·73; 95 % CI 1·10, 2·70, P=0·014) was associated with higher odds for stunting. Stunting was also associated with higher plasma sTfR (>8·3 mg/l) concentrations.
The association between stunting and lower birth weight, shorter maternal height and male sex reflects possibly the intergenerational origins of stunting. Therefore, interventions that focus on improving preconceptual and maternal nutritional status, combined with strategies to promote appropriate infant feeding practices, may be an important strategy to prevent stunting in vulnerable settings.
Plocamopherus ocellatus, a conspicuous but very rare Erythraean nudibranch, was first collected in the Mediterranean Sea off the Israeli coast in 1977, but no additional observations from Israeli waters were recorded in the scientific literature. Biodiversity assessment surveys of the hard bottom biota off the Mediterranean coast of Israel and sightings by recreational divers/underwater photographers in the past dozen years seem to support the presence of a local self-sustaining population off the Israeli coast.
To determine whether real-time availability of rapid molecular results of Staphylococcus aureus would impact emergency department clinician antimicrobial selection for adults with cutaneous abscesses.
We performed a prospective, randomized controlled trial comparing a rapid molecular test with standard of care culture-based testing. Follow-up telephone calls were made at between 2 and 7 days, 1 month, and 3 months after discharge.
Two urban, academic emergency departments.
Patients at least 18 years old presenting with a chief complaint of abscess, cellulitis, or insect bite and receiving incision and drainage were eligible. Seven hundred seventy-eight people were assessed for eligibility and 252 met eligibility criteria.
Clinician antibiotic selection and clinical outcomes were evaluated. An ad hoc outcome of test performance was performed.
We enrolled 252 patients and 126 were randomized to receive the rapid test. Methicillin-susceptible S. aureus–positive patients receiving rapid test results were prescribed beta-lactams more often than controls (absolute difference, 14.5% [95% CI, 1.1%–30.1%]) whereas methicillin-resistant S. aureus–positive patients receiving rapid test results were more often prescribed anti–methicillin-resistant S. aureus antibiotics (absolute difference, 21.5% [95% CI, 10.1%–33.0%]). There were no significant differences between the 2 groups in 1-week or 3-month clinical outcomes.
Availability of rapid molecular test results after incision and drainage was associated with more-targeted antibiotic selection.
The warty comb jelly, Leucothea multicornis, was noted off the Mediterranean coast of Israel in May and June 2014. Though recorded multiple times in the western and central Mediterranean Sea, this is the first record of the species from the eastern basin. The transient localized blooms and longer-term persistent increases in native and alien ctenophore abundance indicate changes in the structure and function of the Levantine ecosystem.
Saron marmoratus, a colourful Indo-Pacific ‘marble shrimp’, is newly recorded in the Mediterranean Sea from specimens recently photographed along the Israeli coastline. The colour pattern of the species is described and illustrated. It is the second Indo-Pacific hippolytid species recorded in the Mediterranean.
Significant progress has been made in the OMVPE growth of GaAs directly on Si by the previously reported low-temperature growth technique. These films have been characterized by low-temperature PL, SIMS, TEM, and DLTS. The epitaxial layers, whose quality has been determined by PL measurements (4.2 K PL spectral width of heavy-hole exciton ≈ 3 meV), were implanted with 29Si+ for fabrication of MESFET channels. Background concentrations of ≈ 1014 cm−3 have been achieved for the first time after rapid thermal annealing without the need to use oxygen implantation or vanadium doping. SIMS measurements do not show Si pileup on the surface or much Si diffusion at the GaAs-Si interface, a significant improvement over earlier results. DLTS measurements and electrical characterization of the GaAs-Si heterojunction diode indicate the presence of only two trap levels (< 1014 cm−3 in concentration) in the GaAs ≥ 2.5 μm away from the interface.
The fabrication of devices based on III-V materials often requires a number of different reactive ion etching (RIE) processes that must be implemented sequentially. These processes are typically carried out in different RIE systems to avoid cross contamination. In this paper, we describe a multichamber RIE system configured to provide several sequential etch processes required for the fabrication of optoelectronic devices. This system has been used to fabricate InGaAsP/lnP ridge waveguide laser arrays with etched mechanical features that enable passive alignment of the lasers with single-mode fibers. Laser arrays with threshold currents as low as 20 mA have been processed with a high degree of uniformity. This system has also been used to develop a laser facet etch process based on CH4/H2/Ar chemistry. This process has been used to fabricate lasers with monolithically integrated rear facet monitors. These etched facet lasers have threshold currents comparable to lasers with both facets cleaved.
The mountain gorilla (Gorilla beringei beringei) lives in two geographically separated populations, Bwindi Impenetrable National Park, Uganda and in three national parks spanning the Virunga mountain region in Rwanda, Democratic Republic of Congo, and Uganda. The altitude, climate and plant composition of these habitats differ. Our goal was to compare the diets of gorillas living in each of these habitats. The nutrients in staple foods and in the diets of individuals in a group of gorillas in Bwindi (N = 12 individuals) and a group in the Virungas (N = 7 individuals) were compared to determine if differences in dietary composition affected concentrations of nutrients in their diets. At both sites gorilla diets consisted primarily of herbaceous leaves, but the diet of Bwindi gorillas contained more tree leaves, fruit, pith and dry wood, and fewer stems. Despite differences in habitat and dietary composition, the nutrient concentrations in both gorilla diets were remarkably similar. On a dry matter basis, the diets and staple foods of Bwindi and Virunga gorillas contained similar concentrations of crude protein (CP), fibre (NDF) and non-structural carbohydrates (TNC). Bwindi gorillas ate diets containing 18% CP, 43% NDF and 19% TNC on a dry-matter basis, while the diets of the Virunga gorillas contained 17% CP, 41% NDF and 18% TNC. Our results demonstrate that gorillas consume diets that differ by plant species and part, but contain similar concentrations of nutrients. This suggests that classifying animals by broad dietary strategy (e.g. frugivory and folivory) does not provide a reliable indicator of the nutritional quality of their diet, and that our previous assumptions about these categories should be re-evaluated.
The outer surfaces of plant leaves and stems are covered with a waxy layer, a considerable fraction of which comprises n-alkanes which are not digested and, therefore, can be used as markers in animal nutrition studies. Most plant species have a characteristic pattern of n-alkane concentrations in their cuticular wax and this enables the diet composition to be estimated by comparison with the pattern of the n-alkanes in faeces. N-alkane recovery in faeces was determined in a digestibility trial involving three different diets given to four goats, six cows and five calves. The validity of using n-alkane markers to determine diet composition was examined in in vivo feeding trials with goats and cows. The recovery of the odd chain length n-alkanes increased linearly with n-alkane chain length, with no significant differences between treatments. Estimates of diet composition were affected by the faecal n-alkane recovery rate. N-alkanes in plant cuticular wax can be used as natural markers for estimating diet composition, but a recovery factor should be used to correct for incomplete recovery in faeces. More research is needed to extend the findings to wider ranges of diets, animals, environmental conditions and physiological and reproductive states.
Pim Martens, International Centre for Integrative Studies, Maastricht University, Maastricht, The Netherlands,
Jan Rotmans, International Centre for Integrative Studies, Maastricht University, Maastricht, The Netherlands,
Dale S. Rothman, International Centre for Integrative Studies, Maastricht University, Maastricht, The Netherlands
Although mathematical modelling is often used by epidemiologists – to gain insights into the observed dynamics of infectious disease epidemics, for example, or to estimate future time trends in diseases – the complex task of estimating future trends and outcomes in relation to global atmospheric change and human health requires the use of integrated, systems-based mathematical models (McMichael & Martens, 1995). Looking at the complexity of the interactions between global (environmental) changes and human health, we need an integrated approach to ensure that key interactions, feedbacks and effects are not inadvertently omitted from the analysis. The various pieces of this complex puzzle can no longer be examined in isolation. Integrated Assessment (IA) aims to fit the pieces of the puzzle together, thereby indicating priorities for policy.
There is increasing recognition and credibility for the rapidly evolving field of IA. Within the setting of the political arena, it is accepted that IA can be supportive in the long-term policy-planning process, while in the scientific community more and more scientists realize the complementary value of IA research.
At present modelling is the dominant method of performing IA, including looking at global-change impacts on human health. However, many studies that are either explicitly or implicitly integrated assessments are still qualitative in nature, without using any models. Furthermore, the complexity of the issues addressed and the value-laden character of assessment activities make it impossible to address this process using only one approach.
The achievement of ignition from an Inertial Confinement
Fusion capsule will require a detailed understanding of
a wide range of high energy density phenomena. This paper
presents some recent work aimed at improving our knowledge
of the strength and equation of state characteristics of
low-Z materials, and outlines data which will
provide quantitative benchmarks against which our predictive
radiation hydrodynamics capabilities can be tested. Improvements
to our understanding in these areas are required if reproducible
and predictable fusion energy production is to be achieved
on the next generation of laser facilities.
In particular, the HELEN laser at AWE has been used to create
a thermal X-ray source with 140 eV peak radiation temperature
and 3% instantaneous flux uniformity to allow measurements
of the Equation of State of materials at pressures up to
20 Mbar to an accuracy of <±2% in shock velocity.
The same laser has been used to investigate the onset of
spallation upon the release of a strong shock at a metal-vacuum
boundary, with dynamic radiography used to image the spalled
material in flight for the first time. Finally, a range
of experiments have been performed to generate quantitative
radiation hydrodynamics data on the evolution of gross
target defects, driven in both planar and imploding geometry.
X-ray radiography was used to record the evolving target
deformation in a system where the X-ray drive and unperturbed
target response were sufficiently characterized to permit
meaningful analysis. The results have been compared to
preshot predictions made using a wide variety of fluid
codes, highlighting substantial differences between the
various approaches, and indicating significant discrepancies
with the experimental reality. The techniques developed
to allow quantitative comparisons are allowing the causes
of the discrepancies to be identified, and are guiding
the development of new simulation techniques.
In 1991 a crew of American, Canadian, and Turkish researchers began a new and comprehensive survey in the Muş Province of Eastern Turkey. The goal of the survey was to study the evolution of settlement and landuse in a marginal zone at the intersection of four great culture areas of the Middle East: Central Anatolia, Western Iran, the Transcaucasus, and Mesopotamia.
This area of Eastern Turkey had been visited previously by I. K. Kökten in 1940s (1947) and Charles Burney in 1950s (1958). Given the large area these surveyors covered and their limited means of transportation, and given the newly excavated material coming from north of the great Taurus mountain massif and from Van (e.g., Sagona 1994, Sagona et al 1992, Çilingiroğlu 1987, 1988), a more comprehensive effort appeared warranted. The first season was six weeks in duration. During that time we re-visited 17 of the sites found by Kökten and Burney, and located 11 new sites. A second season was launched in 1993 with the aim of covering areas not surveyed previously (see Figure 1), mostly in the northern foothills and higher elevations near Hamurpet Lake. Unfortunately, conditions did not permit us to do a second season, nor is a season in the very near future likely. We, therefore, will be publishing the results we have already arrived at, aware that our sample is not complete.
Paralysis of the tongue due to isolated bilateral hypoglossal nerve palsy is a rare occurrence. Due to a trauma the cause in our case may have been a traction injury to both hypoglossal nerves at the base of skull. In some cases a contributing factor may be malformation of the skull base. Most cases have a good prognosis for recovery.
In the June 1987 issue of this Review, Stanley Rothman and S. Robert Lichter offered evidence to support their argument that “the new environmental movement in the United States is partly a symbolic issue,” that elites in the news media and in public interest groups misrepresent the dangers of nuclear energy as a surrogate for more direct criticism of liberal capitalism in the United States. In this controversy, Charles J. Helm expresses skeptictem about the Rothman-Lichter line of argument; and they respond.
Diffusion of 18O in the superconductor La2−x Srx CuO4−y has been measured as a function of x (0 to 0.20) between 300 and 500°C at an oxygen partial pressure of ≍ 1 atm. Concentration profiles were obtained using a secondary ion mass spectrometer. The diffusion coefficient decreases with increasing Sr additions from 0.1 to 0.2, primarily because of an increase in activation energy. This result, which is contradictory to the expectation that the diffusion coefficient should increase with increasing vacancy concentration caused by the added Sr, can be explained if oxygen vacancies are bound to Sr clusters. Measurements on samples with x = 0 or 0.05 were unsuccessful, probably because of porosity.
Tracer diffusion of 60Co and 63Ni in the amorphous alloy NiZr near the equiatomic composition has been measured in the temperature range between 486 and 641 K using the ion-beam sputter-sectioning technique for serial sectioning. The temperature dependence for the diffusivities of Co and Ni in a-NiZr exhibit Arrhenius behavior; these can be expressed as follows: D∗co = 3.6 × 10−7 exp [− (135 ± 14) kJ mol−1 /RT] m2/s and D∗Ni = 1.7 × 10−7 exp [− (140 ± 9) kJ mol−1 /RT] m2/s. The values of D∗Ni are in good agreement with those measured by the Rutherford backscattering technique. The measured diffusivities were independent of time, indicating that no relaxation took place during diffusion.
Changing U.S. attitudes toward new technologies are examined, as are explanations of such changes. We hypothesize that increased concern with the risks of new technologies by certain elite groups is partly a surrogate for underlying ideological criticisms of U.S. society. The question of risk is examined within the framework of the debate over nuclear energy. Studies of various leadership groups are used to demonstrate the ideological component of risk assessment. Studies of scientists' and journalists' attitudes, media coverage of nuclear energy, and public perception of scientists' views suggest both that journalists' ideologies influence their coverage of nuclear energy and that media coverage of the issue is partly responsible for public misperceptions of the views of scientists. We conclude with a discussion of the historical development of the environmental movement in the 1960s and 1970s and the relation of this movement to the public's declining support for nuclear energy.