316 research outputs found
The synthesis of monomers with pendent ethynyl group for modified high performance thermoplastics
The objectives of this project were to develop synthetic schemes for the following classes of modified monomers: (1) difunctional triarylethanes with pendent acetylenic groups; and (2) tertiary aspartimides with terminal acetylene groups at the two ends. Our efforts have resulted in the successful development of high yield schemes for the syntheses of several diamino and bisphenolic analogs of difunctional triarylethanes with pendent ethynyl group. A scheme for one new tertiary aspartimide was also established. Multi-gram samples of all prepared new monomers were provided to our technical contact at NASA-LaRC and preliminary polymerization studies were encouraging. Details of the accomplished work within the last four years are described
The impact of climate change on household food security in the Bongo District of the Upper East Region of Ghana
The study determined the impact of climate change on household food security, investigated awareness level and identified coping strategies used to mitigate negative impact of climate change in the Bongo District with emphasis on women. It was a cross-sectional survey conducted in four purposively selected farming communities in the District in the Upper East Region of Ghana. A sample size of 246 women participated in the study. Using a structured questionnaire, data were collected on socio-demographic characteristics of the participants, awareness of climate change, food consumption patterns, coping strategies and household food security. Data on rainfall and temperature for the past 30 years period in the District were obtained from the Ghana Meteorological Service. Crop yields data over a period of 21 years in the District was also obtained from the Ministry of Food and Agriculture (MOFA). The results revealed that rainfall in the Bongo District has been decreasing at - 0.3 mm per annum and maximum temperature has been increasing at 0.005 °C. More than half (62.6%) of the participants were aware of climate change in their communities. Majority (89.4%) of the participants reduced the quality and quantity of diets as coping strategy method during food shortage periods and almost all (97.2%) of the households were food insecure. Participants who reported to have observed decrease in rainfall were more likely to be food insecure (OR = 3.96; CI = 0.56 – 27.81). Participants were aware of climate change and employed reduction in the quality and quantity of diet as coping mechanism. Almost all households were food insecure. There is the need to intensify climate resistant agriculture technology such as irrigation methods to offset the negative impact of climate change on food security in the District.
The synthesis of monomers with pendent ethynyl groups for modified high performance thermoplastics
Synthetic schemes were developed and optimized for twelve new monomers possessing unique structural features and one aspartimide. Two synthetic pathways were compared for preparation of the triarylethane monomers with pendent ethynyl groups. The results show that one of these pathways can be generally applied. The alternative pathway was applicable to the preparation of only one of the twelve compounds, the problem being secondary reactions of the initially formed desired product
HAM-5 functions as a MAP kinase scaffold during cell fusion in Neurospora crassa.
Cell fusion in genetically identical Neurospora crassa germlings and in hyphae is a highly regulated process involving the activation of a conserved MAP kinase cascade that includes NRC-1, MEK-2 and MAK-2. During chemotrophic growth in germlings, the MAP kinase cascade members localize to conidial anastomosis tube (CAT) tips every ∼8 minutes, perfectly out of phase with another protein that is recruited to the tip: SOFT, a recently identified scaffold for the MAK-1 MAP kinase pathway in Sordaria macrospora. How the MAK-2 oscillation process is initiated, maintained and what proteins regulate the MAP kinase cascade is currently unclear. A global phosphoproteomics approach using an allele of mak-2 (mak-2Q100G) that can be specifically inhibited by the ATP analog 1NM-PP1 was utilized to identify MAK-2 kinase targets in germlings that were potentially involved in this process. One such putative target was HAM-5, a protein of unknown biochemical function. Previously, Δham-5 mutants were shown to be deficient for hyphal fusion. Here we show that HAM-5-GFP co-localized with NRC-1, MEK-2 and MAK-2 and oscillated with identical dynamics from the cytoplasm to CAT tips during chemotropic interactions. In the Δmak-2 strain, HAM-5-GFP localized to punctate complexes that did not oscillate, but still localized to the germling tip, suggesting that MAK-2 activity influences HAM-5 function/localization. However, MAK-2-GFP showed cytoplasmic and nuclear localization in a Δham-5 strain and did not localize to puncta. Via co-immunoprecipitation experiments, HAM-5 was shown to physically interact with NRC-1, MEK-2 and MAK-2, suggesting that it functions as a scaffold/transport hub for the MAP kinase cascade members for oscillation and chemotropic interactions during germling and hyphal fusion in N. crassa. The identification of HAM-5 as a scaffold-like protein will help to link the activation of MAK-2 cascade to upstream factors and proteins involved in this intriguing process of fungal communication
Indirect Evidence For Substantial Damping of Low-Mode Internal Tides In the Open Ocean
A global high-resolution ocean circulation model forced by atmospheric fields and the M2 tidal constituent is used to explore plausible scenarios for the damping of low-mode internal tides. The plausibility of different damping scenarios is tested by comparing the modeled barotropic tides with TPXO8, a highly accurate satellite-altimetry-constrained tide model, and by comparing the modeled coherent baroclinic tide amplitudes against along-track altimetry. Five scenarios are tested: (1) a topographic internal wave drag, argued here to represent the breaking of unresolved high vertical modes, applied to the bottom flow (default configuration), (2) a wave drag applied to the barotropic flow, (3) absence of wave drag, (4) a substantial increase in quadratic bottom friction along the continental shelves (with wave drag turned off), and (5) application of wave drag to the barotropic flow at the same time that quadratic bottom friction is substantially increased along the shelves. Of the scenarios tested here, the default configuration (1) yields the most accurate tides. In all other scenarios (2–5), the lack of damping on open ocean baroclinic motions yields baroclinic tides that are too energetic and travel too far from their sources, despite the presence of a vigorous mesoscale eddy field which can scatter and decohere internal tides in the model. The barotropic tides are also less accurate in the absence of an open ocean damping on barotropic motions, that is, in scenarios (3) and (4). The results presented here suggest that low-mode internal tides experience substantial damping in the open ocean
Household Financial Capability and Economic Hardship: An Empirical Examination of the Financial Capability Framework
This study investigates the components and mechanisms of the financial capability framework using national representative data from the 2015 National Financial Capability Study with the structural equation modeling approach. We find financial socialization and financial education are significantly associated with both financial access and financial literacy, which are associated with positive financial behavior and negatively associated with economic hardship. We further find that financial access plays a more pronounced role in the mediation effects decomposition compared to financial literacy. Our findings demonstrate that financial capability lies in both the opportunity to act and the ability to act—with opportunity relatively more important than ability—and that financial capability is strongly associated with household experiences of economic hardship. Policies and programs should provide accessible and affordable financial products as well as enhance effective financial education and guidance to promote financial inclusion
On the interplay between horizontal resolution and wave drag and their effect on tidal baroclinic mode waves in realistic global ocean simulations
Attitudes towards persons with mental health conditions and psychosocial disabilities as rights holders in Ghana: a World Health Organization study
Background: There are currently major efforts underway in Ghana to address stigma and discrimination, and promote the human rights of those with mental health conditions, within mental health services and the community, working with the World Health Organization’s QualityRights initiative. The present study aims to investigate attitudes towards people with lived experience of mental health conditions and psychosocial disabilities as rights holders. Methods: Stakeholders within the Ghanaian mental health system and community, including health professionals, policy makers, and persons with lived experience, completed the QualityRights pre-training questionnaire. The items examined attitudes towards coercion, legal capacity, service environment, and community inclusion. Additional analyses explored how far participant factors may link to attitudes. Results: Overall, attitudes towards the rights of persons with lived experience were not well aligned with a human rights approach to mental health. Most people supported the use of coercive practices and often thought that health practitioners and family members were in the best position to make treatment decisions. Health/mental health professionals were less likely to endorse coercive measures compared to other groups. Conclusion: This was the first in-depth study assessing attitudes towards persons with lived experience as rights holders in Ghana, and frequently attitudes did not comply with human rights standards, demonstrating a need for training initiatives to combat stigma and discrimination and promote human rights
Semidiurnal Internal Tide Energy Fluxes and Their Variability in a Global Ocean Model and Moored Observations
We examine the temporal means and variability of the semidiurnal internal tide energy fluxes in 1/25° global simulations of the Hybrid Coordinate Ocean Model (HYCOM) and in a global archive of 79 historical moorings. Low-frequency flows, a major cause of internal tide variability, have comparable kinetic energies at the mooring sites in model and observations. The computed root-mean-square (RMS) variability of the energy flux is large in both model and observations and correlates positively with the time-averaged flux magnitude. Outside of strong generation regions, the normalized RMS variability (the RMS variability divided by the mean) is nearly independent of the flux magnitudes in the model, and of order 23% or more in both the model and observations. The spatially averaged flux magnitudes in observations and the simulation agree to within a factor of about 1.4 and 2.4 for vertical mode-1 and mode-2, respectively. The difference in energy flux computed from the full-depth model output versus model output subsampled at mooring instrument depths is small. The global historical archive is supplemented with six high-vertical resolution moorings from the Internal Waves Across the Pacific (IWAP) experiment. The model fluxes agree more closely with the high-resolution IWAP fluxes than with the historical mooring fluxes. The high variability in internal tide energy fluxes implies that internal tide fluxes computed from short observational records should be regarded as realizations of a highly variable field, not as “means” that are indicative of conditions at the measurement sites over all time
A Systems Biology Approach to Infectious Disease Research: Innovating the Pathogen-Host Research Paradigm
The twentieth century was marked by extraordinary advances in our understanding of microbes and infectious disease, but pandemics remain, food and waterborne illnesses are frequent, multidrug-resistant microbes are on the rise, and the needed drugs and vaccines have not been developed. The scientific approaches of the past—including the intense focus on individual genes and proteins typical of molecular biology—have not been sufficient to address these challenges. The first decade of the twenty-first century has seen remarkable innovations in technology and computational methods. These new tools provide nearly comprehensive views of complex biological systems and can provide a correspondingly deeper understanding of pathogen-host interactions. To take full advantage of these innovations, the National Institute of Allergy and Infectious Diseases recently initiated the Systems Biology Program for Infectious Disease Research. As participants of the Systems Biology Program, we think that the time is at hand to redefine the pathogen-host research paradigm
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