Stability of Phyllosilicates on Mars

This study investigates the stability of phyllosilicates on the surface of Mars through laboratory experiments and analysis of terrestrial analogs. Phyllosilicates are mostly found in the oldest Noachian terrains on Mars and hence hold clues to the planet\u27s earliest aqueous and geologic history. Phyllosilicates relevant to Mars were heated up to ~1100°C for up to 24 hours and impacted with projectile velocities up to ~4.5 km/s. Heated samples were analyzed using x-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy in the near- (NIR, 1.0-2.5 µm) and mid-infrared (MIR, 5.0-15.0 µm) ranges. Impacted samples were also analyzed using Raman spectroscopy and cathodoluminescence (CL). Because of the precise evolution with temperature, NIR spectra can be used to estimate the temperature to which a sample was heated. At higher temperatures (\u3e 700°C), MIR spectra are better for identifying secondary phase formation. All shocked samples, except prehnite, showed evidence of destruction of their mineralogical structure. NIR spectra of shocked clays were not strongly affected but their MIR spectra changed significantly. This could explain some discrepancies between NIR and thermal IR spectra of some phyllosilicates found in association with impact craters on Mars. The IR spectra can help determine formation processes by enabling a distinction between clays that were pre-existing and altered by impacts and those that were formed by impact-induced hydrothermal processes. Shocked serpentine partially transformed into magnesite, indicating shock-induced carbonation of serpentine which has never been shown before. These processes could explain the close association between serpentine and magnesite around impact craters on Mars. To better understand phyllosilicate formation and alteration on Mars, terrestrial analogs were also investigated. Samples from the intrabasaltic bole beds from the Deccan Volcanic Province, India, were analyzed. Red layers contained hematite and montmorillonite; yellow layers contained vermiculite and montmorillonite; green layers contained celadonite and nontronite. While the Deccan samples are all mineralogically different, they are chemically similar to each other and to the underlying original basalt, suggesting transformation from one mineral to the next without ion transfer or loss. In fact, celadonite transforms into smectites often with a vermiculite-intermediate step. This may help explain the stratigraphy of Mawrth Vallis, suggesting an evolution of the alteration process from deuteric alteration to low-temperature weathering in a closed system

Maturation of sensory gating performance in children with and without sensory processing disorders

Recent interest in sensory gating in children with and without neuropsychological disorders has resulted in a number of studies and the results regarding the developmental trajectory of sensory gating are inconsistent. We investigated the maturational course of sensory gating in samples of typically developing children and children with sensory processing deficits (SPD) and compared their performance to adults. Besides gating ratios, we also examined the brain responses to conditioning and test click stimuli in the sensory gating paradigm separately to clarify if the changes in click amplitudes could explain the maturational change in the T/C ratio in children. Eighteen adults with no known disorders, 25 typical children, and 28 children with SPD participated in this study. The children ranged in ages between 5 and12 years. The three groups differed in their P50 and N100 ERP components. Both child groups displayed significantly less gating than the adults. Children with SPD demonstrated significantly less gating and more within-group variability compared to typical children. There were significant relationships between age and T/C ratios and between age and peak-to-peak amplitude of the conditioning click in typical children but not in children with SPD. Typical children demonstrated significantly smaller brain response amplitudes to the clicks as compared to adults . These findings suggest that there is a maturational course of sensory gating in typical children and if there is a maturational trajectory in children with SPD it appears to be different than typical children. In addition, children with SPD were found to be lacking in their ability to filter out repeated auditory input and failed to selectively regulate their sensitivity to sensory stimuli

Middle and Late Latency ERP Components Discriminate between Adults, Typical Children, and Children with Sensory Processing Disorders

This study examined whether combinations of middle latency sensory evoked potential components and late components, possibly indicative of cognitive processing, can discriminate between three sample groups; 18 adults (20–55 years), 25 typical children (5–10 years) and 28 children with sensory processing disorders (SPD) (5–12 years). Electroencephalography (EEG) recordings were made while participants heard random presentations of two auditory stimuli (1 and 3 kHz) each at two intensities (50 and 70 dB). Amplitude and latency measurements were obtained for the N1, P2, N2, and P3 components from the averaged event-related potential (ERP) for each of the four auditory stimuli. Discriminant analyses revealed two functions, one which described the relationship of the components on SPD deficit continuum and one which described the relationship of these components on a developmental continuum. Together, these two functions correctly classified 90.5% of the participants as to their group membership. These results are discussed in relation to neurodevelopmental theories

Nurses’ perceptions of the sustainability of a standardised assessment for preventing complications in a ICU: a qualitative study

Background: Quality improvement projects have been widely adopted to prevent complications in the ICU. Objective: This paper describes nurses' perceptions of implementation strategies and the potential sustainability of a practice change intervention to prevent complications in a Malaysian ICU. Design: A participatory action research using five focus group discussions were undertaken with 19 nurses in a single ICU in regional Malaysia. Focus group transcripts were analysed using thematic analysis. Results: The main themes derived from the interviews were: [1] Empowering staff to embrace evidence-based practices; [2] Staff knowledge, attitudes, and beliefs that impact on behaviour; and [3] management support and leadership are influential in staff behaviours (acceptance & perseverance of change process). Discussion: Resistance to change was recognized as a barrier to adopting evidence based recommendations. There is a need to improve nurses' knowledge, attitude and awareness of the importance of assessment for VAP, CRBSI and PIs in the ICU

Water, water everywhere: is Integrated Water Resource Management the right institutional prescription for South Africa's water management challenges?

Publisher versionOstrom (2007) and Ostrom and Cox (2010) argue that natural resource management has been plagued by the “panacea problem": that one-size-fits-all solutions to allocation and management problems have been applied without due consideration of the specific context. The outcome has been the disappointing results of many development and management programs. Integrated Water Resource Management (IWRM) has been recognised as a potentially effective way of allocating water where there are multiple, sometimes competing, users (Saravanan et al. 2009). It has been used successfully in a number of other developing country contexts, including Mexico, Brazil, India and Thailand (Orne-Giliemann 2008; Meinzen-Dick 2007). The principles of IWRM were also adopted in South Africa under the National Water Act (1998). Water User Associations (WUA) are seen as one of the key institutions driving IWRM, since they are designed to allow stake-holders at local level a say in the allocation and management of this important public good (Aoki 2001). However, WUAs in South Africa have mostly not been a success and are currently being reviewed at national level. For the most part, emerging black farmers and rural communities still do not have equal access to water, or a meaningful role in decision-making, and there are significant security of supply and allocation issues with regard to municipal users as well. Using the AID (Institutional Analysis and Development) framework (Ostrom 2007), with particular reference to economic theory relating to incentives and transactions costs, this paper asks if IWRM is a panacea treatment that does not fit the diagnosis of South Africa's water management problems. A case study approach is used, focusing on one of the few established WUAs in the Sundays River Valley Municipality in a rural area of South Africa

FcγRI-Deficient Mice Show Multiple Alterations to Inflammatory and Immune Responses

AbstractThe inactivation of the mouse high-affinity IgG Fc receptor FcγRI resulted in a wide range of defects in antibody Fc-dependent functions. These studies showed the primary importance of FcγRI in endocytosis of monomeric IgG, kinetics, and extent of phagocytosis of immune complexes, in macrophage-based ADCC, and in immune complex-dependent antigen presentation to primed T cells. In the absence of FcγRI, antibody responses were elevated, implying the removal of a control point by the deletion of FcγRI. In addition, FcR-γ chain-deficient mice were found to express partially functional FcγRI. Thus, FcγRI is an early participant in Fc-dependent cell activation and in the development of immune responses

Friendship networks and physical activity and sedentary behavior among youth: a systematized review

BACKGROUND: Low levels of physical activity and increased participation in sedentary leisure-time activities are two important obesity-risk behaviors that impact the health of today’s youth. Friend’s health behaviors have been shown to influence individual health behaviors; however, current evidence on the specific role of friendship networks in relation to levels of physical activity and sedentary behavior is limited. The purpose of this review was to summarize evidence on friendship networks and both physical activity and sedentary behavior among children and adolescents. METHOD: After a search of seven scientific databases and reference scans, a total of thirteen articles were eligible for inclusion. All assessed the association between friendship networks and physical activity, while three also assessed sedentary behavior. RESULTS: Overall, higher levels of physical activity among friends are associated with higher levels of physical activity of the individual. Longitudinal studies reveal that an individual’s level of physical activity changes to reflect his/her friends’ higher level of physical activity. Boys tend to be influenced by their friendship network to a greater extent than girls. There is mixed evidence surrounding a friend’s sedentary behavior and individual sedentary behavior. CONCLUSION: Friends’ physical activity level appears to have a significant influence on individual’s physical activity level. Evidence surrounding sedentary behavior is limited and mixed. Results from this review could inform effective public health interventions that harness the influence of friends to increase physical activity levels among children and adolescents

Use of an electronic medical record to monitor efficacy of diabetes care in out-patients in a central hospital in Malawi: Patterns of glycaemic control and lessons learned

The Malawian health sector has a strong tradition of systematic data collection for monitoring and evaluation of large-scale services. A highly successful adapted Directly Observed Treatment, Short course “DOTS” framework, based on patient registers and paperbased mastercards was introduced to facilitate the management and monitoring of the scale up of antiretroviral therapy. Subsequently, a simple, touch-screen based electronic medical record system (EMRs) was effectively introduced at high burden ART sites. Based on this model, in 2010, a diabetes specific EMRs was introduced in the diabetes clinic at Queen Elizabeth Central Hospital. In this paper we report on the first 3 years experience with the diabetes EMRs. We highlight the strengths and weaknesses of the diabetes EMRs and present data on glycaemic control recorded in the system

Co- evolving wing spots and mating displays are genetically separable traits in Drosophila

The evolution of sexual traits often involves correlated changes in morphology and behavior. For example, in Drosophila, divergent mating displays are often accompanied by divergent pigment patterns. To better understand how such traits co- evolve, we investigated the genetic basis of correlated divergence in wing pigmentation and mating display between the sibling species Drosophila elegans and Drosophila gunungcola. Drosophila elegans males have an area of black pigment on their wings known as a wing spot and appear to display this spot to females by extending their wings laterally during courtship. By contrast, D. gunungcola lost both of these traits. Using Multiplexed Shotgun Genotyping (MSG), we identified a - ¼440 kb region on the X chromosome that behaves like a genetic switch controlling the presence or absence of male- specific wing spots. This region includes the candidate gene optomotor- blind (omb), which plays a critical role in patterning the Drosophila wing. The genetic basis of divergent wing display is more complex, with at least two loci on the X chromosome and two loci on autosomes contributing to its evolution. Introgressing the X- linked region affecting wing spot development from D. gunungcola into D. elegans reduced pigmentation in the wing spots but did not affect the wing display, indicating that these are genetically separable traits. Consistent with this observation, broader sampling of wild D. gunungcola populations confirmed that the wing spot and wing display are evolving independently: some D. gunungcola males performed wing displays similar to D. elegans despite lacking wing spots. These data suggest that correlated selection pressures rather than physical linkage or pleiotropy are responsible for the coevolution of these morphological and behavioral traits. They also suggest that the change in morphology evolved prior to the change in behavior.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155953/1/evolution2019submissionsupplementaryfigurescompiledcompressed.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155953/2/evo13990_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155953/3/evo13990.pd