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Epidemiology and potential preventative measures for viral infections in children with malignancy and those undergoing hematopoietic cell transplantation.

In pediatric patients with malignancy and those receiving hematopoietic stem cell transplants, bacterial and fungal infections have been the focus of fever and neutropenia episodes for decades. However, improved diagnostic capabilities have revealed viral pathogens as a significant cause of morbidity and mortality. Because of limited effective antiviral therapies, prevention of viral infections is paramount. Pre-exposure and post-exposure prophylaxis and antiviral suppressive therapeutic approaches are reviewed. Additionally, infection control practices specific to this patient population are discussed. A comprehensive approach utilizing each of these can be effective at reducing the negative impact of viral infections

Analgesic Management of Pain in Elite Athletes: A Systematic Review

Objective: To identify the prevalence, frequency of use, and effects of analgesic pain management strategies used in elite athletes. Design: Systematic literature review. Data Sources: Six databases: Ovid/Medline, SPORTDiscus, CINAHL, Embase, Cochrane Library, and Scopus. Eligibility Criteria for Selecting Studies: Empirical studies involving elite athletes and focused on the use or effects of medications used for pain or painful injury. Studies involving recreational sportspeople or those that undertake general exercise were excluded. Main Results: Of 70 articles found, the majority examined the frequency with which elite athletes use pain medications, including nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, anesthetics, and opioids. A smaller set of studies assessed the effect of medications on outcomes such as pain, function, and adverse effects. Oral NSAIDs are reported to be the most common medication, being used in some international sporting events by over 50% of athletes. Studies examining the effects of pain medications on elite athletes typically involved small samples and lacked control groups against which treated athletes were compared. Conclusions: Existing empirical research does not provide a sufficient body of evidence to guide athletes and healthcare professionals in making analgesic medication treatment decisions. Based on the relatively robust evidence regarding the widespread use of NSAIDs, clinicians and policymakers should carefully assess their current recommendations for NSAID use and adhere to a more unified consensus-based strategy for multidisciplinary pain management in elite athletes. In the future, we hope to see more rigorous, prospective studies of various pain management strategies in elite athletes, thus enabling a shift from consensus-based recommendations to evidence-based recommendations

BK Lyncis: The Oldest Old Nova?... And a Bellwether for Cataclysmic-Variable Evolution

We summarize the results of a 20-year campaign to study the light curves of BK Lyncis, a nova-like star strangely located below the 2-3 hour orbital period gap in the family of cataclysmic variables. Two apparent "superhumps" dominate the nightly light curves - with periods 4.6% longer, and 3.0% shorter, than P_orb. The first appears to be associated with the star's brighter states (V~14), while the second appears to be present throughout and becomes very dominant in the low state (V~15.7). Starting in the year 2005, the star's light curve became indistinguishable from that of a dwarf nova - in particular, that of the ER UMa subclass. Reviewing all the star's oddities, we speculate: (a) BK Lyn is the remnant of the probable nova on 30 December 101, and (b) it has been fading ever since, but has taken ~2000 years for the accretion rate to drop sufficiently to permit dwarf-nova eruptions. If such behavior is common, it can explain other puzzles of CV evolution. One: why the ER UMa class even exists (because all members can be remnants of recent novae). Two: why ER UMa stars and short-period novalikes are rare (because their lifetimes, which are essentially cooling times, are short). Three: why short-period novae all decline to luminosity states far above their true quiescence (because they're just getting started in their postnova cooling). Four: why the orbital periods, accretion rates, and white-dwarf temperatures of short-period CVs are somewhat too large to arise purely from the effects of gravitational radiation (because the unexpectedly long interval of enhanced postnova brightness boosts the mean mass-transfer rate). These are substantial rewards in return for one investment of hypothesis: that the second parameter in CV evolution, besides P_orb, is time since the last classical-nova eruption.Comment: PDF, 46 pages, 4 tables, 10 figures; in preparation; more info at http://cbastro.org

UTILIZING UAV PAYLOAD DESIGN BY UNDERGRADUATE RESEARCHERS FOR EDUCATIONAL AND RESEARCH DEVELOPMENT

ABSTRACT An undergraduate team consisting of mechanical and electrical engineering students at the University of North Dakota developed an electro-optical and un-cooled thermal infrared digital imaging remote sensing payload for an Unmanned Aerial Vehicle (UAV). The first iteration of the payload design began in the fall of 2005 and the inaugural flight tests took place at Camp Ripley, Minnesota, a National Guard facility, in the fall of 2006 with a corporate partner. The second iteration design with increased performance in object tracking and data processing is expected to fly in the summer of 2007. Payload development for integration into a UAV is a process that is not currently well defined by industrial practices or regulated by government. These processes are a significant part of the research being conducted in order to define the "best practices." The emerging field of UAVs generates tremendous interest and serves to attract quality students into the research. As with many emerging technologies there are many new exciting developments, however, the fundamentals taught in core courses are still critical to the process and serve as the basis of the system. In this manner, the program stimulates innovative design while maintaining a solid connection to undergraduate courses and illustrates the importance of advanced courses. The payload development was guided by off-the-shelf components and software using a systems engineering methodology throughout the project. Many of the design and payload flight constraints were based on external factors, such as difficulties with access to airspace, weatherrelated delays, and ITAR restrictions on hardware. Overall, the research project continues to be a tremendous experiential learning activity for mechanical and electrical engineering students, as well as for the faculty members. The process has been extremely successful in enhancing the expertise in systems engineering and design in the students and developing the UAV payload design knowledge base and necessary infrastructure at the university

An international validation of the AO spine subaxial injury classification system.

PURPOSE To validate the AO Spine Subaxial Injury Classification System with participants of various experience levels, subspecialties, and geographic regions. METHODS A live webinar was organized in 2020 for validation of the AO Spine Subaxial Injury Classification System. The validation consisted of 41 unique subaxial cervical spine injuries with associated computed tomography scans and key images. Intraobserver reproducibility and interobserver reliability of the AO Spine Subaxial Injury Classification System were calculated for injury morphology, injury subtype, and facet injury. The reliability and reproducibility of the classification system were categorized as slight (ƙ = 0-0.20), fair (ƙ = 0.21-0.40), moderate (ƙ = 0.41-0.60), substantial (ƙ = 0.61-0.80), or excellent (ƙ = > 0.80) as determined by the Landis and Koch classification. RESULTS A total of 203 AO Spine members participated in the AO Spine Subaxial Injury Classification System validation. The percent of participants accurately classifying each injury was over 90% for fracture morphology and fracture subtype on both assessments. The interobserver reliability for fracture morphology was excellent (ƙ = 0.87), while fracture subtype (ƙ = 0.80) and facet injury were substantial (ƙ = 0.74). The intraobserver reproducibility for fracture morphology and subtype were excellent (ƙ = 0.85, 0.88, respectively), while reproducibility for facet injuries was substantial (ƙ = 0.76). CONCLUSION The AO Spine Subaxial Injury Classification System demonstrated excellent interobserver reliability and intraobserver reproducibility for fracture morphology, substantial reliability and reproducibility for facet injuries, and excellent reproducibility with substantial reliability for injury subtype

Pattern of neurological recovery in persons with an acute cervical spinal cord injury over the first 14 days post injury

IntroductionFollowing a traumatic spinal cord injury (SCI) it is critical to document the level and severity of injury. Neurological recovery occurs dynamically after injury and a baseline neurological exam offers a snapshot of the patient's impairment at that time. Understanding when this exam occurs in the recovery process is crucial for discussing prognosis and acute clinical trial enrollment. The objectives of this study were to: (1) describe the trajectory of motor recovery in persons with acute cervical SCI in the first 14 days post-injury; and (2) evaluate if the timing of the baseline neurological assessment in the first 14 days impacts the amount of motor recovery observed.MethodsData were obtained from the Rick Hansen Spinal Cord Injury Registry (RHSCIR) site in Vancouver and additional neurological data was extracted from medical charts. Participants with a cervical injury (C1–T1) who had a minimum of three exams (including a baseline and discharge exam) were included. Data on the upper-extremity motor score (UEMS), total motor score (TMS) and American Spinal Injury Association (ASIA) Impairment Scale (AIS) were included. A linear mixed-effect model with additional variables (AIS, level of injury, UEMS, time, time2, and TMS) was used to explore the pattern and amount of motor recovery over time.ResultsTrajectories of motor recovery in the first 14 days post-injury showed significant improvements in both TMS and UEMS for participants with AIS B, C, and D injuries, but was not different for high (C1–4) vs. low (C5–T1) cervical injuries or AIS A injuries. The timing of the baseline neurological examination significantly impacted the amount of motor recovery in participants with AIS B, C, and D injuries.DiscussionTiming of baseline neurological exams was significantly associated with the amount of motor recovery in cervical AIS B, C, and D injuries. Studies examining changes in neurological recovery should consider stratifying by severity and timing of the baseline exam to reduce bias amongst study cohorts. Future studies should validate these estimates for cervical AIS B, C, and D injuries to see if they can serve as an “adjustment factor” to control for differences in the timing of the baseline neurological exam

Differential Histopathological and Behavioral Outcomes Eight Weeks after Rat Spinal Cord Injury by Contusion, Dislocation, and Distraction Mechanisms

The objective of this study was to compare the long-term histological and behavioral outcomes after spinal cord injury (SCI) induced by one of three distinct biomechanical mechanisms: dislocation, contusion, and distraction. Thirty male Sprague-Dawley rats were randomized to incur a traumatic cervical SCI by one of these three clinically relevant mechanisms. The injured cervical spines were surgically stabilized, and motor function was assessed for the following 8 weeks. The spinal cords were then harvested for histologic analysis. Quantification of white matter sparing using Luxol fast blue staining revealed that dislocation injury caused the greatest overall loss of white matter, both laterally and along the rostrocaudal axis of the injured cord. Distraction caused enlarged extracellular spaces and structural alteration in the white matter but spared the most myelinated axons overall. Contusion caused the most severe loss of myelinated axons in the dorsal white matter. Immunohistochemistry for the neuronal marker NeuN combined with Fluoro Nissl revealed that the dislocation mechanism resulted in the greatest neuronal cell losses in both the ventral and dorsal horns. After the distraction injury mechanism, animals displayed no recovery of grip strength over time, in contrast to the animals subjected to contusion or dislocation injuries. After the dislocation injury mechanism, animals displayed no improvement in the grooming test, in contrast to the animals subjected to contusion or distraction injuries. These data indicate that different SCI mechanisms result in distinct patterns of histopathology and behavioral recovery. Understanding this heterogeneity may be important for the future development of therapeutic interventions that target specific neuropathology after SCI