SANDBOX CONTRACTING: AN EVALUATION OF GAMIFIED VS. TRADITIONAL CONTRACTING TRAINING METHODS AT THE USAF ENLISTED CONTRACTING TECHNICAL SCHOOL

This thesis involved an evaluation of gamified versus current (traditional) training methods employed by the instructors and faculty at the Air Force’s 344th Training Squadron (344 TRS) at Lackland Air Force Base, Texas, and by the professors at the Naval Postgraduate School (NPS) in Monterey, California. For our project, we designed and developed a first-person shooter (FPS) video game, titled Sandbox Contracting, that teaches the player basic contracting skills. Over the course of six weeks, we utilized this FPS video game to conduct an experiment in which a control group received the current (traditional) training methods employed by 344 TRS and NPS and a treatment group received the gamified version of the training. We assessed each student’s learning as well as their reaction to the assigned learning modality (traditional versus gaming) using post-training evaluation surveys. Traditional training methods outperformed gamified methods in most cases, but not all. We found that game design and mechanics impacted the student’s reactions and ultimately, the success of using gamified methods for learning. Additionally, the results demonstrated a genuine interest in using games for learning among the Air Force contracting students, given the right game design and mechanics. Lastly, we offer suggestions for areas in which further research should be conducted in the gamified versus traditional training arena.Outstanding ThesisCaptain, United States Air ForceCaptain, United States Air ForceCaptain, United States Air ForceApproved for public release. Distribution is unlimited

25 Gb/s data transmission over a 1.4 m long multimode polymer spiral waveguide

Data transmission studies of a 1.4m long multimode polymer spiral waveguide using an 850nm VCSEL are presented. Error-free 25 Gb/s data transmission is demonstrated over that waveguide length, achieving a record bandwidth-length product of 21GHz×m

Gamification in Defense Acquisition Training and Education

Excerpt from the Proceedings of the Nineteenth Annual Acquisition Research SymposiumLeveraging research conducted as part of an Acquisition Research Program sponsored thesis, this paper expands upon an essay written by our research team (submitted to USNI), in which we argue that gamified learning (building games to promote learning of traditional material) presents a unique opportunity for enhancing education and training within the defense workforce. We provide an in-depth explanation of what gamification is and why it might be particularly useful for enhancing learning in non-traditional defense contexts, using defense acquisition as a test case. We present initial evidence from our empirical research to highlight the opportunities and challenges for advancing military education into the present age through gamified learning methods. Finally, we outline future directions for research in gamification for defense applications, bringing attention to the need for collaboration across the defense-focused entities exploring the potential for gaming in future defense education and training.Approved for public release; distribution is unlimited

High Density Circumstellar Interaction in the Luminous Type IIn SN 2010jl: The first 1100 days

HST and ground based observations of the Type IIn SN 2010jl are analyzed, including photometry, spectroscopy in the ultraviolet, optical and NIR bands, 26-1128 days after first detection. At maximum the bolometric luminosity was $\sim 3\times10^{43}$ erg/s and even at 850 days exceeds $10^{42}$ erg/s. A NIR excess, dominating after 400 days, probably originates in dust in the circumstellar medium (CSM). The total radiated energy is $> 6.5\times10^{50}$ ergs, excluding the dust component. The spectral lines can be separated into one broad component due to electron scattering, and one narrow with expansion velocity $\sim 100$ km/s from the CSM. The broad component is initially symmetric around zero velocity but becomes blueshifted after $\sim 50$ days, while remaining symmetric about a shifted centroid velocity. Dust absorption in the ejecta is unlikely to explain the line shifts, and we attribute the shift instead to acceleration by the SN radiation. From the optical lines and the X-ray and dust properties, there is strong evidence for large scale asymmetries in the CSM. The ultraviolet lines indicate CNO processing in the progenitor, while the optical shows a number of narrow coronal lines excited by the X-rays. The bolometric light curve is consistent with a radiative shock in an $r^{-2}$ CSM with a mass loss rate of $\sim 0.1$ M_sun/yr. The total mass lost is $> 3$ M_sun. These properties are consistent with the SN expanding into a CSM characteristic of an LBV progenitor with a bipolar geometry. The apparent absence of nuclear processing is attributed to a CSM still opaque to electron scattering.Comment: ApJ in press. Updated and changed after referees comment

Scintillate: An open-source graphical viewer for time-series calcium imaging evaluation and pre-processing

Background Calcium imaging is based on the detection of minute signal changes in an image time-series encompassing pre- and post-stimuli. Depending on the function of the elicited response, change may be pronounced, as in the case of a genetically encoded calcium-reporter protein, or subtle, as is the case in a bath-applied dye system. Large datasets are thus often acquired and appraised only during post-processing where specific Regions of Interest (ROIs) are examined.    New method  The scintillate software provides a platform allowing for near instantaneous viewing of time-sequenced tiffs within a discrete GUI environment. Whole sequences may be evaluated. In its simplest form scintillate provides change in florescence (ΔF) across the entiretiffimage matrix. Evaluating image intensity level differences across the whole image allows the user to rapidly establish the value of the preparation, withouta prioriROI-selection. Additionally, an implementation of Independent Component Analysis (ICA) provides additional rapid insights into areas of signal change.   Results  We imaged transgenic flies expressing Calcium-sensitive reporter proteins within projection neurons and moth mushroom bodies stained with a Ca2+sensitive bath-applied dye. Instantaneous pre-stimulation background subtraction allowed us to appraise strong genetically encoded neuronal Ca2+responses in flies and weaker, less apparent, responses within moth mushroom bodies. Comparison with existing methods At the time of acquisition, whole matrix ΔF analysis alongside ICA is ordinarily not performed. We found it invaluable, minimising time spent with unresponsive samples, and assisting in optimisation of subsequent acquisitions.   Conclusions  We provide a multi-platform open-source system to evaluate time-series images. Abbreviations ΔF,change of intensity between frames; ICA,independent component analysi

Non-invasive kinetic modelling of PET tracers with radiometabolites using a constrained simultaneous estimation method: evaluation with 11C-SB201745.

BACKGROUND: Kinetic analysis of dynamic PET data requires an accurate knowledge of available PET tracer concentration within blood plasma over time, known as the arterial input function (AIF). The gold standard method used to measure the AIF requires serial arterial blood sampling over the course of the PET scan, which is an invasive procedure and makes this method less practical in clinical settings. Traditional image-derived methods are limited to specific tracers and are not accurate if metabolites are present in the plasma. RESULTS: In this work, we utilise an image-derived whole blood curve measurement to reduce the computational complexity of the simultaneous estimation method (SIME), which is capable of estimating the AIF directly from tissue time activity curves (TACs). This method was applied to data obtained from a serotonin receptor study (11C-SB207145) and estimated parameter results are compared to results obtained using the original SIME and gold standard AIFs derived from arterial samples. Reproducibility of the method was assessed using test-retest data. It was shown that the incorporation of image-derived information increased the accuracy of total volume of distribution (V T) estimates, averaged across all regions, by 40% and non-displaceable binding potential (BP ND) estimates by 16% compared to the original SIME. Particular improvements were observed in K1 parameter estimates. BP ND estimates, based on the proposed method and the gold standard arterial sample-derived AIF, were not significantly different (P=0.7). CONCLUSIONS: The results of this work indicate that the proposed method with prior AIF information obtained from a partial volume corrected image-derived whole blood curve, and modelled parent fraction, has the potential to be used as an alternative non-invasive method to perform kinetic analysis of tracers with metabolite products

Risk of Psychosis Among Individuals Who Have Presented to Hospital With Self-harm:A Prospective Nationwide Register Study in Sweden

BACKGROUND AND HYPOTHESIS: Recent research showed that young people who presented to hospital with self-harm in Finland had a significantly elevated risk of later psychosis. We investigated the prospective relationship between hospital presentation for self-harm and risk of psychosis in an unprecedentedly large national Swedish cohort.STUDY DESIGN: We used inpatient and outpatient healthcare registers to identify all individuals born between 1981 and 1993 who were alive and living in Sweden on their 12th birthday and who presented to hospital one or more times with self-harm. We compared them with a matched cohort, followed up for up to 20 years, and compared the cumulative incidence of psychotic disorders. Furthermore, we examined whether the strength of the relationship between hospital presentation for self-harm and later psychosis changed over time by examining for cohort effects.STUDY RESULTS: In total, 28 908 (2.0%) individuals presented to hospital with self-harm without prior psychosis diagnosis during the follow-up. For individuals who presented to hospital with self-harm, the cumulative incidence of diagnosed psychosis was 20.7% at 20 years follow-up (hazard radio = 13.9, 95% CI 13.3-14.6, P-value &lt;5 × 10-308). There was no evidence of a dilution of the effect over time: while the incidence of hospital self-harm presentation increased, this did not result in an attenuation over time of the strength of the relationship between hospital self-harm presentation and subsequent psychosis.CONCLUSIONS: Individuals who present to hospital with self-harm in their teens and 20s represent an important risk group for psychosis prediction and prevention.</p

Acute hypoxia increases the cerebral metabolic rate:a magnetic resonance imaging study

The aim of the present study was to examine changes in cerebral metabolism by magnetic resonance imaging of healthy subjects during inhalation of 10% O(2) hypoxic air. Hypoxic exposure elevates cerebral perfusion, but its effect on energy metabolism has been less investigated. Magnetic resonance imaging techniques were used to measure global cerebral blood flow and the venous oxygen saturation in the sagittal sinus. Global cerebral metabolic rate of oxygen was quantified from cerebral blood flow and arteriovenous oxygen saturation difference. Concentrations of lactate, glutamate, N-acetylaspartate, creatine and phosphocreatine were measured in the visual cortex by magnetic resonance spectroscopy. Twenty-three young healthy males were scanned for 60 min during normoxia, followed by 40 min of breathing hypoxic air. Inhalation of hypoxic air resulted in an increase in cerebral blood flow of 15.5% (p = 0.058), and an increase in cerebral metabolic rate of oxygen of 8.5% (p = 0.035). Cerebral lactate concentration increased by 180.3% ([Formula: see text]), glutamate increased by 4.7% ([Formula: see text]) and creatine and phosphocreatine decreased by 15.2% (p [Formula: see text]). The N-acetylaspartate concentration was unchanged (p = 0.36). In conclusion, acute hypoxia in healthy subjects increased perfusion and metabolic rate, which could represent an increase in neuronal activity. We conclude that marked changes in brain homeostasis occur in the healthy human brain during exposure to acute hypoxia

Serum magnesium and calcium levels in relation to ischemic stroke

Objective: To determine whether serum magnesium and calcium concentrations are causally associated with ischemic stroke or any of its subtypes using the mendelian randomization approach. Methods: Analyses were conducted using summary statistics data for 13 single-nucleotide polymorphisms robustly associated with serum magnesium (n = 6) or serum calcium (n = 7) concentrations. The corresponding data for ischemic stroke were obtained from the MEGASTROKE consortium (34,217 cases and 404,630 noncases). Results: In standard mendelian randomization analysis, the odds ratios for each 0.1 mmol/L (about 1 SD) increase in genetically predicted serum magnesium concentrations were 0.78 (95% confidence interval [CI] 0.69–0.89; p = 1.3 × 10−4) for all ischemic stroke, 0.63 (95% CI 0.50–0.80; p = 1.6 × 10−4) for cardioembolic stroke, and 0.60 (95% CI 0.44–0.82; p = 0.001) for large artery stroke; there was no association with small vessel stroke (odds ratio 0.90, 95% CI 0.67–1.20; p = 0.46). Only the association with cardioembolic stroke was robust in sensitivity analyses. There was no association of genetically predicted serum calcium concentrations with all ischemic stroke (per 0.5 mg/dL [about 1 SD] increase in serum calcium: odds ratio 1.03, 95% CI 0.88–1.21) or with any subtype. Conclusions: This study found that genetically higher serum magnesium concentrations are associated with a reduced risk of cardioembolic stroke but found no significant association of genetically higher serum calcium concentrations with any ischemic stroke subtype