Acute Management of Minor Head Injury

Minor head injury (MHI) is a major socioeconomic and health burden throughout the world. However, many controversies exist about the best acute management. In this thesis the extent of practice variation in acute management of MHI at the emergency department is investigated. Because CT decision rules and guidelines play a crucial role in the acute management of patients with MHI, this thesis focused on how these CT rules could be improved

Brandname confusion: Subjective and objective measures of orthographic similarity

Determining brand name similarity is vital in areas of trademark registration and brand confusion. Students rated the orthographic (spelling) similarity of word pairs (Experiments 1, 2, and 4) and brand name pairs (Experiment 5). Similarity ratings were consistently higher when words shared beginnings rather than endings, whereas shared pronunciation of the stressed vowel had small and less consistent effects on ratings. In Experiment 3 a behavioral task confirmed the similarity of shared beginnings in lexical processing. Specifically, in a task requiring participants to decide whether 2 words presented in the clear (a probe and a later target) were the same or different, a masked prime word preceding the target shortened response latencies if it shared its initial 3 letters with the target. The ratings of students for word and brand name pairs were strongly predicted by metrics of orthographic similarity from the visual word identification literature based on the number of shared letters and their relative positions. The results indicate a potential use for orthographic metrics in brand name registration and trademark law

Asymmetry of the latent heat signature in b-axis oriented single crystal Gd Si Ge

A 100 micron fragment of a b-axis oriented single crystal Gd Si Ge has been studied using microcalorimetry, enabling the separate measurement of the heat capacity and the latent heat. The sample was taken from the same crystal previously studied with Hall probe imaging, which showed that the phase transition is seeded by a second phase of Gd Si Ge nanoplatelets on the increasing field sweep direction only. The multiple transition features observed in the latent heat signature suggests a nucleation size of approximately 20 μm, consistent with the lengthscale suggested by Hall imaging. The difference in nucleation and growth process with field sweep direction is clearly identified in the latent heat. We show that the latent heat contribution to the entropy change is of the order of 50% of the total entropy change and unlike other systems studied, the transition does not broaden (and the latent heat contribution does not diminish significantly) as magnetic field and temperature are increased within the parameter range explored in these experiments

Embryonic thermal manipulation and dietary fat source during acute heat stress : 1. Effect on hatchability and broiler performance

Modern broilers have been selected for rapid growth but demonstrate reduced heat tolerance toward market age. As the poultry industry expands globally, strategies must be developed to support broiler performance in challenging climates. The objective of this study was to evaluate the effect of embryonic thermal manipulation (TM) and dietary fat source during the finisher period on broiler performance during acute heat stress (AHS) close to market age. The cyclic exposure to high temperatures during mid-incubation used in TM has been demonstrated to improve broiler tolerance to heat stress. However, high incubation temperatures can be detrimental to embryonic development and impair posthatch broiler performance. Embryos were exposed to 39.5°C for 12 h daily from incubation day 7 to 16 to assess the impact of TM on hatching and broiler performance. Dietary fat is commonly added to poultry diets during heat stress and it was theorized that differences in fat source may further impact bird performance. Finisher diets were supplemented with soya oil, poultry fat, or olive oil at 4.5% each. Broilers were exposed to a period of AHS at 43 d. Embryo mortality was increased, and hatchability was reduced by TM. Broiler performance was also decreased for the TM birds, but mortality during AHS was markedly reduced. Dietary fat source did not influence bird performance but was shown to interact with incubation treatment. Overall, the present data suggest optimal performance in modern broiler strains may be at odds with improved heat tolerance.The North Carolina Department of Agriculture and Consumer Services Piedmont Research Station, as well as the North Carolina State University Prestage Department of Poultry Science and Feed Mill.https://www.sciencedirect.com/journal/journal-of-applied-poultry-researchhj2022Animal and Wildlife Science

Impact of guidelines for the management of minor head injury on the utilization and diagnostic yield of CT over two decades, using natural language processing in a large dataset

Objectives We investigated the impact of clinical guidelines for the management of minor head injury on utilization and diagnostic yield of head CT over two decades. Methods Retrospective before-after study using multiple electronic health record data sources. Natural language processing algorithms were developed to rapidly extract indication, Glasgow Coma Scale, and CT outcome from clinical records, creating two datasets: one based on all head injury CTs from 1997 to 2009 (n = 9109), for which diagnostic yield of intracranial traumatic findings was calculated. The second dataset (2009–2014) used both CT reports and clinical notes from the emergency department, enabling selection of minor head injury patients (n = 4554) and calculation of both CT utilization and diagnostic yield. Additionally, we tested for significant changes in utilization and yield after guideline implementation in 2011, using chi-square statistics and logistic regression. Results The yield was initially nearly 60%, but in a decreasing trend dropped below 20% when CT became routinely used for head trauma. Between 2009 and 2014, of 4554 minor head injury patients overall, 85.4% underwent head CT. After guideline implementation in 2011, CT utilization significantly increased from 81.6 to 87.6% (p = 7 × 10−7 ), while yield significantly decreased from 12.2 to 9.6% (p = 0.029). Conclusions The number of CTs performed for head trauma gradually increased over two decades, while the yield decreased. In 2011, despite implementation of a guideline aiming to improve selective use of CT in minor head injury, utilization significantly increased

Modeling the influence of snow cover on low Arctic net ecosystem exchange

The Arctic net ecosystem exchange (NEE) of CO2 between the land surface and the atmosphere is influenced by the timing of snow onset and melt. The objective of this study was to examine whether uncertainty in model estimates of NEE could be reduced by representing the influence of snow on NEE using remote sensing observations of snow cover area (SCA). Observations of NEE and time-lapse images of SCA were collected over four locations at a low Arctic site (Daring Lake, NWT) in May-June 2010. Analysis of these observations indicated that SCA influences NEE, and that good agreement exists between SCA derived from time-lapse images, Landsat and MODIS. MODIS SCA was therefore incorporated into the vegetation photosynthesis respiration model (VPRM). VPRM was calibrated using observations collected in 2005 at Daring Lake. Estimates of NEE were then generated over Daring Lake and Ivotuk, Alaska (2004-2007) using VPRM formulations with and without explicit representations of the influence of SCA on respiration and/or photosynthesis. Model performance was assessed by comparing VPRM output against unfilled eddy covariance observations from Daring Lake and Ivotuk (2004-2007). The uncertainty in VPRM estimates of NEE was reduced when respiration was estimated as a function of air temperature when SCA ≤ 50% and as a function of soil temperature when SCA > 50%

The damping width of giant dipole resonances of cold and hot nuclei: a macroscopic model

A phenomenological macroscopic model of the Giant Dipole Resonance (GDR) damping width of cold- and hot-nuclei with ground-state spherical and near-spherical shapes is developed. The model is based on a generalized Fermi Liquid model which takes into account the nuclear surface dynamics. The temperature dependence of the GDR damping width is accounted for in terms of surface- and volume-components. Parameter-free expressions for the damping width and the effective deformation are obtained. The model is validated with GDR measurements of the following nuclides, $^{39,40}$K, $^{42}$Ca, $^{45}$Sc, $^{59,63}$Cu, $^{109-120}$Sn,$^{147}$Eu, $^{194}$Hg, and $^{208}$Pb, and is compared with the predictions of other models.Comment: 10 pages, 5 figure

Using High Frequency Transcranial Random Noise Stimulation to Modulate Face Memory Performance in Younger and Older Adults: Lessons Learnt From Mixed Findings

High-frequency transcranial random noise stimulation (tRNS) has been shown to improve a range of cognitive and perceptual abilities. Here we sought to examine the effects of a single session of tRNS targeted at the ventrolateral prefrontal cortices (VLPFC) on face memory in younger and older adults. To do so, we conducted three experiments. In Experiment 1, we found that younger adults receiving active tRNS outperformed those receiving sham stimulation (i.e., using a between-participant factor for stimulation condition; Experiment 1). This effect was not observed for object memory (car memory) in younger adults (Experiment 2), indicating that the effect is not a general memory effect. In Experiment 3, we sought to replicate the effects of Experiment 1 using a different design (within-participant factor of stimulation – active or sham tRNS to the same individual) and to extend the study by including older adult participants. In contrast to Experiment 1, we found that active tRNS relative to sham tRNS reduced face memory performance in both younger and older adults. We also found that the degree of decline in performance in the active tRNS relative to sham tRNS condition was predicted by baseline ability, with higher performing participants showing the largest decreases in performance. Overall, the results indicate that tRNS to the VLPFC modulates face memory, but that there may be performance and protocol specific moderators of this effect. We discuss these findings in the context of the broader literature showing the importance of individual variation in the outcome of non-invasive brain stimulation intervention approaches. We conclude that while tRNS may have potential as an intervention approach, generalizing from single experiment studies to wide application is risky and caution should be adopted in interpreting findings

Stable isotope food-web analysis and mercury biomagnification in polar bears ( Ursus maritimus )

Mercury (Hg) biomagnification occurs in many ecosystems, resulting in a greater potential for toxicological effects in higher-level trophic feeders. However, Hg transport pathways through different food-web channels are not well known, particularly in high-latitude systems affected by the atmospheric Hg deposition associated with snow and ice. Here, we report on stable carbon and nitrogen isotope ratios, and Hg concentrations, determined for 26, late 19th and early 20th century, polar bear ( Ursus maritimus ) hair specimens, collected from catalogued museum collections. These data elucidate relationships between the high-latitude marine food-web structure and Hg concentrations in polar bears. The carbon isotope compositions of polar bear hairs suggest that polar bears derive nutrition from coupled food-web channels, based in pelagic and sympagic primary producers, whereas the nitrogen isotope compositions indicate that polar bears occupy > fourth-level trophic positions. Our results show a positive correlation between polar bear hair Hg concentrations and δ 15 N. Interpretation of the stable isotope data in combination with Hg concentrations tentatively suggests that polar bears participating in predominantly pelagic food webs exhibit higher mercury concentrations than polar bears participating in predominantly sympagic food webs.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73930/1/j.1751-8369.2009.00114.x.pd