Thermal and albedo mapping of the north and south polar regions of Mars

The first maps of the thermal properties of the north and south polar region of Mars are presented. The maps complete the mapping of the entire planet. The maps for the north polar region were derived from Viking Infrared Thermal Mapper (IRTM) observations obtained from 10 Jun. to 30 Sep. 1978. This period corresponds to the early summer season in the north, when the north residual water ice cap was exposed, and the polar surface temperatures were near their maximum. The maps in the south were derived from observations obtained between 24 Aug. to 23 Sep. 1977. This period corresponds to the late summer season in the south, when the seasonal polar cap had retreated to close to its residual configuration, and the second global dust storm of 1977 had largely subsided. The major results concerning the following topics are summarized: (1) surface water ice; (2) polar dune material; and (3) dust deposits

Bots as Virtual Confederates: Design and Ethics

The use of bots as virtual confederates in online field experiments holds extreme promise as a new methodological tool in computational social science. However, this potential tool comes with inherent ethical challenges. Informed consent can be difficult to obtain in many cases, and the use of confederates necessarily implies the use of deception. In this work we outline a design space for bots as virtual confederates, and we propose a set of guidelines for meeting the status quo for ethical experimentation. We draw upon examples from prior work in the CSCW community and the broader social science literature for illustration. While a handful of prior researchers have used bots in online experimentation, our work is meant to inspire future work in this area and raise awareness of the associated ethical issues.Comment: Forthcoming in CSCW 201

The Impact of Ice Layers on Gas Transport through Firn at the North Greenland Eemian Ice Drilling (Neem) Site, Greenland

Typically, gas transport through firn is modeled in the context of an idealized firn column. However, in natural firn, imperfections are present, which can alter transport dynamics and therefore reduce the accuracy of reconstructed climate records. For example, ice layers have been found in several firn cores collected in the polar regions. Here, we examined the effects of two ice layers found in a NEEM, Greenland firn core on gas transport through the firn. These ice layers were found to have permeability values of 3.0 and 4.0 × 10−10 m2, and are therefore not impermeable layers. However, the shallower ice layer was found to be significantly less permeable than the surrounding firn, and can therefore retard gas transport. Large closed bubbles were found in the deeper ice layer, which will have an altered gas composition than that expected because they were closed near the surface after the water phase was present. The bubbles in this layer represent 12% of the expected closed porosity of this firn layer after the firn-ice transition depth is reached, and will therefore bias the future ice core gas record. The permeability and thickness of the ice layers at the North Greenland Eemian Ice Drilling (NEEM) site suggest that they do not disrupt the firn-air concentration profiles and that they do not need to be accounted for in gas transport models at NEEM

Aeromedical Issues in Diabetic Aviators

Diabetes mellitus is a common disease that poses a serious health and safety threat to civilian aviators. Complications secondary to diabetes can be severe and result in sudden incapacitation. The Federal Aviation Administration (FAA) has developed regulations for certifying aviators with diabetes, as well as guidelines for in-flight management of blood glucose levels. Advances in medical technology have led to treatments and countermeasures for diabetes that enable many individuals to engage in physically and mentally demanding activities. This paper presents a basic overview of the pathophysiology, diagnosis, and management of diabetes mellitus in civil aviators. In addition, current FAA regulations for medical certification and blood glucose management will be outlined

Progress report on the ultra heavy cosmic ray experiment (AO178)

The Ultra Heavy Cosmic Ray Experiment (UHCRE) is based on a modular array of 192 side-viewing solid state nuclear track detector stacks. These stacks were mounted in sets of four in 48 pressure vessels employing sixteen peripheral Long Duration Exposure Facility (LDEF) trays. The extended duration of the LDEF mission has resulted in a greatly enhanced scientific yield from the UHCRE. The geometry factor for high energy cosmic ray nuclei, allowing for Earth shadowing, was 30 sq m-sr, giving a total exposure factor of 170 sq m-sr-y at an orbital inclination of 28.4 degrees. Scanning results indicate that about 3000 cosmic ray nuclei in the charge region with Z greater than 65 were collected. This sample is more than ten times the current world data in the field (taken to be the data set from the HEAO-3 mission plus that from the Ariel-6 mission) and is sufficient to provide the world's first statistically significant sample of actinide (Z greater than 88) cosmic rays. Results to date are presented including details of ultra-heavy cosmic ray nuclei, analysis of pre-flight and post-flight calibration events and details of track response in the context of detector temperature history. The integrated effect of all temperature and age related latent track variations cause a maximum charge shift of +/- 0.8 e for uranium and +/- 0.6 e for the platinum-lead group. The precision of charge assignment as a function of energy is derived and evidence for remarkably good charge resolution achieved in the UHCRE is considered. Astrophysical implications of the UHCRE charge spectrum are discussed

The LDEF ultra heavy cosmic ray experiment

The LDEF Ultra Heavy Cosmic Ray Experiment (UHCRE) used 16 side viewing LDEF trays giving a total geometry factor for high energy cosmic rays of 30 sq m sr. The total exposure factor was 170 sq m sr y. The experiment is based on a modular array of 192 solid state nuclear track detector stacks, mounted in sets of four in 48 pressure vessels. The extended duration of the LDEF mission has resulted in a greatly enhanced potential scientific yield from the UHCRE. Initial scanning results indicate that at least 1800 cosmic ray nuclei with Z greater than 65 were collected, including the world's first statistically significant sample of actinides. Post flight work to date and the current status of the experiment are reviewed

THE EFFECTS OF MARKER SIZE ON THE ACCURACY OF THE ARlEL PERFORMANCEANALYSIS SYSTEM (APASTM)

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THE EFFECTS OF MARKER SIZE ON THE ACCURACY OF THE ARlEL PERFORMANCEANALYSIS SYSTEM (APAStm)

INTRODUCTION In order to increase the efficiency of today's motion analysis systems, most systems are capable of auto digization. In order for the APAS system to auto digitize, retroreflective markers must be used for accurate tracing of the movement. During auto digization, the computer's software will search a given area for pixels that are above a pre-determined light threshold. From these threshold pixels, the software will calculate the center of the marker. To increase the accuracy of the measurements, it has been suggested that the larger the marker, the more accurate the measurement. The purpose of this study was to examine the effects of marker size on the accuracy of the APAS system. METHODS Eight retroreflective markers were placed upon an inverted T-shaped pendulum. Tbelve reference angles were calculated from these markers. Four different starting positions were used (static, a 45 deg, a 90 deg, and a 120 deg. release position) while using four different marker sizes (0.45,0.95, 1.27, and 1.91 cm.) for a total of 16 different conditions. Ten trials were done for each condition. Tbenty frames were auto-digitized from each trial. Frame 10 represented the low point of the trajectory for the dynamic conditions. Deviations were calculated by taking the average angle over the 20 frames and subtracting it from the reference angle. The data was analyzed using a Mixed Effects ANOVA. Inter-trial variability was determined by subtracting the reconstructed angle from the reference angle on a frame by frame basis. RESULTS Significance was found in the ANOVA of marker [F (3,1893) = 6.39, p < 0.00031 and position [F (3,1893) = 350.41, p < 0.00011. Contrast tests indicate that markers 1-3 were all statistically different from marker 4 (p < 0.001, p < 0.0003, p < 0.0106). The least square means of marker showed that as the marker size increased the deviation on average decreased (0.4339 deg. to 0.3883 deg.). Examination of the inter-trial variability showed that the variability increased from the static position up to the 120 deg. position. CONCLUSION Marker size was shown to have a significant effect upon the accuracy of the APAS system. Examination of the least square means seems to indicate that the smallest marker size had the most error and the largest marker size had the least error. It should be noted though that regardless of marker size the error was no greater than 0.5 degrees. For most motion analysis procedures an error of this magnitude is probably an acceptable error

Clinically Applicable Sociolinguistic Assessment for Cognitive-Communication Disorders

Purpose: The third International Cognitive-Communication Disorders Conference was held in early 2022, providing an opportunity for researchers and clinicians to discuss management of cognitive-communication disorders (CCDs). Presentations that addressed social discourse initiated broader conversations about implementing sociolinguistic methods in research and clinical contexts. Given the heterogeneity of CCDs and sociocultural contexts, a person-centered approach is needed. Sociolinguistic methods are inherently relevant and salient to the individual\u27s communication context and partners. Sociolinguistic analyses provide information about language skills, cognitive-communication skills, and social cognition. The purpose of this article is to share a model of social communication and provide descriptions of current methods that can be used by researchers and clinicians to capture the complexity of social communication, thereby advancing our knowledge and practice. Conclusion: Although there is a growing literature base that supports the inclusion of sociolinguistic methods, there remains a disconnect between the literature and clinical application that current researchers and practitioners have an opportunity to address

Upper body movement analysis of multiple limb asymmetry in 367 clinically lame horses

Background Compensatory lameness is common in horses and evaluation can be challenging. Objectives To investigate patterns of compensatory movements in clinical cases with fore- or hindlimb lameness before and after diagnostic analgesia. Study design Retrospective clinical study. Methods Multiple limb lameness of 367 horses was characterised by type (push-off, impact or mixed), limb (fore- or hindlimb in predominant lameness) and side (ipsi- or contralateral in concurrent lameness) using a body-mounted inertial sensor (BMIS). Diagnostic analgesia was performed until the percentage improvement of the vector sum in forelimb lameness and the mean difference of the maximum or minimum pelvic height (PDmax or PDmin) in hindlimb lameness was >= 50%. Linear mixed model and post-estimation of effects were performed by contrast command with multiple comparisons adjusted by Bonferroni method. Correlation of pre- and post-analgesia of all head and pelvis asymmetry parameters was tested with Spearman's rank correlation. Results Improvement in vector sum per mm after diagnostic analgesia in forelimb impact lameness positively correlated with decrease in PDmax in contralateral mixed lameness (0.187 mm, r = .58, P < .05). Improvement in PDmin per mm after diagnostic analgesia in hindlimb mixed and PDmax in hindlimb push-off lameness decreased vector sum in ipsilateral forelimb impact lameness by 0.570 and 0.696 mm, respectively (P < .05), with no positive correlation. Main limitations A variety of cases with inhomogeneous distribution of lameness patterns was investigated retrospectively, therefore, it is impossible to distinguish between true multiple limb lameness and compensatory lameness in this clinical material. Conclusions Various asymmetry patterns of concurrent lameness were seen in horses with naturally occurring primary forelimb impact lameness with contralateral compensatory hindlimb lameness with a mixed component being the most common. In horses with hindlimb lameness, compensatory movements were seen in ipsilateral forelimbs, mostly as an ipsilateral impact lameness during straight line trot