Improved discrimination in photographic density contouring

Density discrimination can be accomplished through use of special photographic contouring material which has two sensitive layers (one negative, one positive) on single support. Process will be of interest to investigators who require finer discrimination of densities of original photograph for purposes such as identification of crops and analysis of energy levels of radiating objects

Predicting the Spread and Management of the Cassava Brown Streak Disease Epidemic

Cassava Brown Streak disease (CBSD) is a viral disease of cassava that causes necrosis of the edible root tissue, which reduces both consumable and marketable yield. In 2004, CBSD emerged in Uganda and has since been spreading rapidly through previously unaffected regions of East Africa and into Central Africa. Preventing spread to West Africa is a major food security and development priority, along with mitigating the impact of CBSD in endemic regions. This thesis focuses on the development of a landscape-scale spatial model of the CBSD epidemic to inform management. Currently, there is disparate information on the epidemiology of CBSD and significant associated uncertainty. We begin with a review of CBSD from an epidemiological perspective. The review focuses on: mechanisms and rates of pathogen dispersal, surveillance, disease impact and management efficacy to inform the structure of the CBSD model. Prior to model development, it was necessary to aggregate all available data on the historic spread of the epidemic. Minimal surveillance data were available in the literature. Therefore, it was necessary to work extensively with East African collaborators to acquire and digitise over 10 years of previously unavailable surveillance records from Uganda and surrounding countries. Extensive post-processing was performed to minimise errors in the data. In parallel with digitisation of the surveillance data, we describe work to enable digital data collection via the creation of a cassava disease surveillance app, along with extensive training. The goal was to minimise errors in data collection and reduce the time lag between disease surveillance and reporting in surveillance programmes. The second section of the thesis describes the development, parameterisation, and validation of a stochastic, spatio-temporal epidemic model for CBSD. Using digitised Ugandan surveillance data from 2005-2010, and estimates of cassava density throughout Uganda and immediately surrounding regions, we apply Approximate Bayesian Computation (ABC) to estimate dispersal parameters, providing methodological details on the development and validation of summary statistics. The model fitting also takes account of empirical data for vector density across Uganda and surrounding regions. The model fits the data well for the training set for 2005-2010. Survey data from Uganda and the surrounding region from 2011-2017 are then used as a rigorous independent test to validate model predictions. The third section of the thesis describes the application of the model to address questions concerning historic, current and future epidemic spread. We use the model to identify reasons why, although there were historically high levels of CBSD infection in Malawi, negligible epidemic spread occurred into Zambia from Malawi showing that low density of cassava cultivation in south east Zambia could account for the inhibition of spread. The model does successfully predict the incursion of the epidemic into north east Zambia from the Democratic Republic of Congo (DRC). We run cross-continent simulations to predict the spatiotemporal spread of the epidemic through central Africa, including DRC and the Central African Republic, where there is very little disease surveillance and reporting for CBSD. The simulations allow us to compute the likely distributions of arrival times of the epidemic in West African countries. We also simulate rates of spread of the disease in West African countries following direct introduction for example by importation and by natural spread from adjoint countries. Finally, we simulate management interventions in Nigeria, to identify the scale and speed at which management programmes would need to be deployed to contain the epidemic. The thesis concludes with a review of the principal results and critical assumptions underlying the results. Some proposals are presented for future work in epidemiological modelling to address practical problems of the management of CBSD.BBSR

In vivo co-localization of enzymes on RNA scaffolds increases metabolic production in a geometrically dependent manner

Co-localization of biochemical processes plays a key role in the directional control of metabolic fluxes toward specific products in cells. Here, we employ in vivo scaffolds made of RNA that can bind engineered proteins fused to specific RNA binding domains. This allows proteins to be co-localized on RNA scaffolds inside living Escherichia coli. We assembled a library of eight aptamers and corresponding RNA binding domains fused to partial fragments of fluorescent proteins. New scaffold designs could co-localize split green fluorescent protein fragments to produce activity as measured by cell-based fluorescence. The scaffolds consisted of either single bivalent RNAs or RNAs designed to polymerize in one or two dimensions. The new scaffolds were used to increase metabolic output from a two-enzyme pentadecane production pathway that contains a fatty aldehyde intermediate, as well as three and four enzymes in the succinate production pathway. Pentadecane synthesis depended on the geometry of enzymes on the scaffold, as determined through systematic reorientation of the acyl-ACP reductase fusion by rotation via addition of base pairs to its cognate RNA aptamer. Together, these data suggest that intra-cellular scaffolding of enzymatic reactions may enhance the direct channeling of a variety of substrates

Ringtails (Bassariscus astutus)

One of the more elusive animals in the desert, ringtails are small unique mammals, native to the American west and southwest, Central and South America (Poglayen-Neuwall & Toweill, 1988). Although seldom seen ringtails populations are not considered threatened in Utah or elsewhere in the United States

House of Delegates, American Pharmaceutical Association. Minutes of the First Session

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Synthetic beta-solenoid proteins with the fragment-free computational design of a beta-hairpin extension

The ability to design and construct structures with atomic level precision is one of the key goals of nanotechnology. Proteins offer an attractive target for atomic design, as they can be synthesized chemically or biologically, and can self-assemble. However the generalized protein folding and design problem is unsolved. One approach to simplifying the problem is to use a repetitive protein as a scaffold. Repeat proteins are intrinsically modular, and their folding and structures are better understood than large globular domains. Here, we have developed a new class of synthetic repeat protein, based on the pentapeptide repeat family of beta-solenoid proteins. We have constructed length variants of the basic scaffold, and computationally designed de novo loops projecting from the scaffold core. The experimentally solved 3.56 ˚A resolution crystal structure of one designed loop matches closely the designed hairpin structure, showing the computational design of a backbone extension onto a synthetic protein core without the use of backbone fragments from known structures. Two other loop designs were not clearly resolved in the crystal structures and one loop appeared to be in an incorrect conformation. We have also shown that the repeat unit can accommodate whole domain insertions by inserting a domain into one of the designed loops

Computational models to improve surveillance for cassava brown streak disease and minimize yield loss.

Cassava brown streak disease (CBSD) is a rapidly spreading viral disease that affects a major food security crop in sub-Saharan Africa. Currently, there are several proposed management interventions to minimize loss in infected fields. Field-scale data comparing the effectiveness of these interventions individually and in combination are limited and expensive to collect. Using a stochastic epidemiological model for the spread and management of CBSD in individual fields, we simulate the effectiveness of a range of management interventions. Specifically we compare the removal of diseased plants by roguing, preferential selection of planting material, deployment of virus-free 'clean seed' and pesticide on crop yield and disease status of individual fields with varying levels of whitefly density crops under low and high disease pressure. We examine management interventions for sustainable production of planting material in clean seed systems and how to improve survey protocols to identify the presence of CBSD in a field or quantify the within-field prevalence of CBSD. We also propose guidelines for practical, actionable recommendations for the deployment of management strategies in regions of sub-Saharan Africa under different disease and whitefly pressure

Melatonin promoted chemotaxins expression in lung epithelial cell stimulated with TNF-α

BACKGROUND: Patients with asthma demonstrate circadian variations in the airway inflammation and lung function. Pinealectomy reduces the total inflammatory cell number in the asthmatic rat lung. We hypothesize that melatonin, a circadian rhythm regulator, may modulate the circadian inflammatory variations in asthma by stimulating the chemotaxins expression in the lung epithelial cell. METHODS: Lung epithelial cells (A549) were stimulated with melatonin in the presence or absence of TNF-α(100 ng/ml). RANTES (Regulated on Activation Normal T-cells Expressed and Secreted) and eotaxin expression were measured using ELISA and real-time RT-PCR, eosinophil chemotactic activity (ECA) released by A549 was measured by eosinophil chemotaxis assay. RESULTS: TNF-α increased the expression of RANTES (307.84 ± 33.56 versus 207.64 ± 31.27 pg/ml of control, p = 0.025) and eotaxin (108.97 ± 10.87 versus 54.00 ± 5.29 pg/ml of control, p = 0.041). Melatonin(10(-10 )to 10(-6)M) alone didn't change the expression of RNATES (204.97 ± 32.56 pg/ml) and eotaxin (55.28 ± 6.71 pg/ml). However, In the presence of TNF-α (100 ng/ml), melatonin promoted RANTES (410.88 ± 52.03, 483.60 ± 55.37, 559.92 ± 75.70, 688.42 ± 95.32, 766.39 ± 101.53 pg/ml, treated with 10(-10), 10(-9), 10(-8), 10(-7),10(-6)M melatonin, respectively) and eotaxin (151.95 ± 13.88, 238.79 ± 16.81, 361.62 ± 36.91, 393.66 ± 44.89, 494.34 ± 100.95 pg/ml, treated with 10(-10), 10(-9), 10(-8), 10(-7), 10(-6)M melatonin, respectively) expression in a dose dependent manner in A549 cells (compared with TNF-α alone, P < 0.05). The increased release of RANTES and eotaxin in A549 cells by above treatment were further confirmed by both real-time RT-PCR and the ECA assay. CONCLUSION: Taken together, our results suggested that melatonin might synergize with pro-inflammatory cytokines to modulate the asthma airway inflammation through promoting the expression of chemotaxins in lung epithelial cell

The Role of Self-Efficacy in Achieving Health Behavior Change

The concept of self-efficacy is receiving increasing recognition as a predictor of health behavior change and maintenance. The purpose of this article is to facilitate a clearer understanding of both the concept and its relevance for health education research and practice. Self-efficacy is first defined and distinguished from other related concepts. Next, studies of the self-efficacy concept as it relates to health practices are examined. This review focuses on cigarette smoking, weight control, contraception, alcohol abuse and exercise behaviors. The studies reviewed suggest strong relationships between self-efficacy and health behavior change and maintenance. Experimental manipulations of self-efficacy suggest that efficacy can be enhanced and that this enhancement is related to subsequent health behavior change. The findings from these studies also suggest methods for modifying health practices. These methods diverge from many of the current, traditional methods for changing health practices. Recommendations for incorporating the enhancement of self-efficacy into health behavior change programs are made in light of the reviewed findings.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68171/2/10.1177_109019818601300108.pd