Identification and expression analysis of CBF/DREB1 and COR15 genes in mutants of Brassica oleracea var. botrytis with enhanced proline production and frost resistance.

Frost resistant mutants of Brassica oleracea var. botrytis were investigated for the presence of CBF/DREB1 and COR15a gene products and induced frost resistance. Total RNA of clones was isolated after 3 h, 6 h, 24 h and 14 d acclimation at 4 °C and proteins and free proline were isolated after 14 d acclimation. cDNA was produced using RT-PCR and the first CBF gene in B. oleracea detected and did quantify. Through SDS-PAGE and Western blotting, the COR15a protein was detected for the first time in B. oleracea. The results confirmed the first report of the presence of BoCBF/DREB1 in B. oleracea and this only appeared under cold acclimation. The sequence analysis of predicted amino acids revealed a very high homology (90%) with CBF sequences of other Brassica species (BnCBF5/DREB1, BrDREB1 and BjDREB1B) and homology reduced to 67% when compared to plants other than Brassicas. BoCBF/DREB1 transcript levels increased up to 24 h acclimation and then declined. Some mutants showed BoCBF/DREB1 expression at 3 h while others only after 6 h and 24 h acclimation. The genotypes showed positive significant correlation between BoCBF/DREB1 expression and frost resistance (R(2) = 0.9343). The proline level under acclimation increased about 8 fold and demonstrated positive and significant correlation with BoCBF/DREB1 expression. Proline also showed positive and significant correlation with frost resistance under cold acclimation but very not under non-acclimation. All clones were positive for COR15a protein after 14 d cold acclimation and expression correlated with frost resistance. Under non-acclimation COR15a was constitutively expressed in 3 mutants

Self-organizing patterns maintained by competing associations in a six-species predator-prey model

Formation and competition of associations are studied in a six-species ecological model where each species has two predators and two prey. Each site of a square lattice is occupied by an individual belonging to one of the six species. The evolution of the spatial distribution of species is governed by iterated invasions between the neighboring predator-prey pairs with species specific rates and by site exchange between the neutral pairs with a probability $X$. This dynamical rule yields the formation of five associations composed of two or three species with proper spatiotemporal patterns. For large $X$ a cyclic dominance can occur between the three two-species associations whereas one of the two three-species associations prevails in the whole system for low values of $X$ in the final state. Within an intermediate range of $X$ all the five associations coexist due to the fact that cyclic invasions between the two-species associations reduce their resistance temporarily against the invasion of three-species associations.Comment: 6 pages, 8 figure

Teaching Happiness: The Role of Positive Psychology in the Classroom

Happiness can be defined in various ways, and characterizing traits that reflect sustained happiness in an individual can be a daunting task. For the purpose of this paper, I propose that contentment regarding the past, satisfaction in the present, optimism about the future, as well as cultivating individual strengths and virtues will result in sustained happiness. Using findings from and relating to the field of positive psychology, I will suggest that these qualities can be fostered in students and will benefit students individually and ultimately society as a whole

Shigella Draft Genome Sequences: Resources for Food Safety and Public Health.

Shigella is a major foodborne pathogen that infects humans and nonhuman primates and is the major cause of dysentery and reactive arthritis worldwide. This is the initial public release of 16 Shigella genome sequences from four species sequenced as part of the 100K Pathogen Genome Project

Evaluation of conventional and molecular strategies for the rapid diagnosis and molecular characterisation of strains of Mycobacterium tuberculosis

Laboratory diagnosis of tuberculosis is often difficult and time consuming. This study has evaluated some new strategies for improved isolation and detection of Mycobacterium tuberculosis in clinical specimens. This work was conducted over several years examining samples from the a high tuberculosis prevalence population in Jeddah, Saudi Arabia and in the low tuberculosis prevalence setting in Queensland, Australia. Commercial nucleic acid amplification technologies were evaluated and compared with in-house real-time quantitative PCR strategies for both pulmonary and extrapulmonary specimens and for paraffin embedded tissue samples. The study examined strategies for the detection of multidrug resistance strains through the use of Lipa assay to detect mutations in the rpoB gene. Variable numbers of tandem DNA repeat (VNTR) typing was applied to samples from Saudi Arabia and Queensland, Australia to assess their discriminatory power and to demonstrate the diversity and uniqueness of strains of M. tuberculosis in distinct geographical regions. A combination of VNTR typing targeting six ETR loci and an additional three polymorphic MIRU loci was applied to a strains of MTB to enhance discrimination of strains. The results demonstrated that culture remains the "gold standard" for diagnosis and that a liquid culture system is essential for timely isolation of mycobacteria. Direct nucleic acid techniques are valuable diagnostic tools in samples where AFBs can be demonstrated but have markedly reduced sensitivity in AFB smear negative MTB culture positive samples. A combination of VNTR and MIRU typing provides excellent discrimination of strains of Mycobacterium tuberculosis. This stable typing strategy relies on PCR which allows for real-time epidemiology of transmission to be monitored.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Comparison of Two Detailed Models of Aedes aegypti Population Dynamics

The success of control programs for mosquito-­borne diseases can be enhanced by crucial information provided by models of the mosquito populations. Models, however, can differ in their structure, complexity, and biological assumptions, and these differences impact their predictions. Unfortunately, it is typically difficult to determine why two complex models make different predictions because we lack structured side-­by-­side comparisons of models using comparable parameterization. Here, we present a detailed comparison of two complex, spatially explicit, stochastic models of the population dynamics of Aedes aegypti, the main vector of dengue, yellow fever, chikungunya, and Zika viruses. Both models describe the mosquito?s biological and ecological characteristics, but differ in complexity and specific assumptions. We compare the predictions of these models in two selected climatic settings: a tropical and weakly seasonal climate in Iquitos, Peru, and a temperate and strongly seasonal climate in Buenos Aires, Argentina. Both models were calibrated to operate at identical average densities in unperturbedconditions in both settings, by adjusting parameters regulating densities in each model (number of larval development sites and amount of nutritional resources). We show that the models differ in their sensitivityto environmental conditions (temperature and rainfall) and trace differences to specific model assumptions.Temporal dynamics of the Ae. aegypti populations predicted by the two models differ more markedly under strongly seasonal Buenos Aires conditions. We use both models to simulate killing of larvae and/or adults with insecticides in selected areas. We show that predictions of population recovery by the models differ substantially, an effect likely related to model assumptions regarding larval development and (director delayed) density dependence. Our methodical comparison provides important guidance for model improvement by identifying key areas of Ae. aegypti ecology that substantially affect model predictions, and revealing the impact of model assumptions on population dynamics predictions in unperturbed and perturbed conditions.Fil: Legros, Mathieu. University of North Carolina; Estados UnidosFil: Otero, Marcelo Javier. Universidad de Buenos Aires; ArgentinaFil: Romeo Aznar, Victoria Teresa. Universidad de Buenos Aires; ArgentinaFil: Solari, Hernan Gustavo. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Gould, Fred. National Institutes of Health; Estados UnidosFil: Lloyd, Alun L.. National Institutes of Health; Estados Unido

Fishing for flies : testing the efficacy of "stink stations" for promoting blow flies as pollinators in mango orchards

Pollinator communities are composed of diverse groups of insects, with radically different life histories and resource needs. Blow flies are known to visit a variety of economically important crop plants. Larval blow flies develop by feeding on decaying animals. Some fruit growers are known to place carrion on farms during the flowering season to attract adult blow flies (Calliphoridae). However, the efficacy of these “stink stations” has not been tested. We conducted a series of experiments to determine: 1) if stink stations promote the abundance of blow flies in mango orchards (Mangifera indica L.), 2) if any increases in the abundance of flies acts to promote pollination and fruit set in Australian mango orchards. Farms with stink stations had approximately three times more flies than control farms. However, the increased abundance of blow flies did not result in increased fruit set. Although stink stations increased the abundance of blow flies, we found no evidence that their use improves mango yield. This may be due to pollination saturation by a highly abundant native hover fly, Mesembrius bengalensis (Syrphidae), during our study. We hypothesize that stink stations may only be beneficial in years or regions where other pollinators are less abundant

EMG Analysis of Neural Activation Patterns of the Gluteal Muscle Complex

Gluteal amnesia is described as a condition in which the neural recruitment patterns of the gluteal muscle complex are insufficient to activate muscle fibers, causing the hamstring and lower back muscles to take up the physical demand. Symptoms due to insufficient gluteal muscle activation include tight hamstrings post-exercise, anterior pelvic tilt, and knee valgus during squat or lunge performance. This could lead to compensation injuries of the lumbar, knee, and ankle joints. Many physical therapy rehabilitation programs of the lower back and lower extremity incorporate gluteal exercises which could potentially treat this condition and prevent compensation injuries. PURPOSE: To identify and test a person experiencing symptoms of gluteal amnesia to determine gluteal muscle activation before and after a therapy program designed to enhance muscle recruitment and function. METHODS: A 74-year-old male experiencing symptoms of unilateral gluteal amnesia was recruited for this case-study. Electromyographic (EMG) analysis of the gluteal muscle complex was recorded while the subject performed movements typically associated with gluteal muscle complex activation. Both the affected and unaffected side were analyzed while the subject performed movements, as well as submaximal and maximal voluntary isometric contractions (MVIC). After baseline testing, a daily, 3-week progressive resistance rehabilitation program consisting of exercises utilizing the gluteal muscle complex was completed. After completion of the rehabilitation program, EMG analysis of the affected and unaffected sides was performed as during the baseline measures. Integrated EMG signals of gluteal activation were compared between pre- and post-tests. Baseline EMG was considered to be 100% of muscle activation. The post-rehabilitation EMG during MVIC was a percentage of the maximal effort output. MVIC of the submaximal tests were obtained by comparing the quadruped hip extension and single leg glute bridge exercises to the standing gluteal squeeze, and the quadruped hip abduction and clam shell exercises to the side lying hip abduction. RESULTS: Increased gluteal complex activation post-rehabilitation was evident in both the affected and unaffected limbs. Specifically, the largest increases of the left and ride side were seen through the quadruped hip extension (18.7%, 52.4%) and quadruped hip abduction (54.1%, 98.8%) exercises, respectively. The left limb presenting with gluteal amnesia symptoms consistently gave lower output values. CONCLUSION: In this case-study, increased EMG activity in the affected muscles, progressive increases in resistance during daily rehabilitation and anecdotal improvements in movement patterns were observed. Based on the results of this case-study, treatment for conditions such as gluteal amnesia and other disorders of ineffective motor unit recruitment should include targeted rehabilitation exercises designed to isolate the affected musculature

The effect of sexual selection on adaptation and extinction under increasing temperatures

Strong sexual selection has been reported to both enhance and hinder the adaptive capacity and persistence of populations when exposed to novel environments. Consequently, how sexual selection influences population adaption and persistence under stress remains widely debated. Here we present two empirical investigations of the fitness consequences of sexual selection on populations of the Indian meal moth, Plodia interpunctella, exposed to stable or gradually increasing temperatures. When faced with increasing temperatures strong sexual selection was associated with both increased fecundity and offspring survival compared to populations experiencing weak sexual selection, suggesting sexual selection acts to drive adaptive evolution by favouring beneficial alleles. Strong sexual selection did not, however, delay extinction when the temperature became excessively high. By manipulating individuals’ mating opportunities during fitness assays we were able to assess the effect of multiple mating independently from the effect of population-level sexual selection, and found that polyandry has a positive effect on both fecundity and offspring survival under increasing temperatures in those populations evolving with weak sexual selection. Within stable temperatures there were some benefits from strong sexual selection but these were not consistent across the entire experiment, possibly reflecting changing costs and benefits of sexual selection under stabilising and directional selection. These results indicate that sexual selection can provide a buffer against climate change and increase adaptation rates within a continuously changing environment. These positive effects of sexual selection may however be too small to protect populations and delay extinction when environmental changes are relatively rapid

Complex population dynamics as a competition between multiple time-scale phenomena

The role of the selection pressure and mutation amplitude on the behavior of a single-species population evolving on a two-dimensional lattice, in a periodically changing environment, is studied both analytically and numerically. The mean-field level of description allows to highlight the delicate interplay between the different time-scale processes in the resulting complex dynamics of the system. We clarify the influence of the amplitude and period of the environmental changes on the critical value of the selection pressure corresponding to a phase-transition "extinct-alive" of the population. However, the intrinsic stochasticity and the dynamically-built in correlations among the individuals, as well as the role of the mutation-induced variety in population's evolution are not appropriately accounted for. A more refined level of description, which is an individual-based one, has to be considered. The inherent fluctuations do not destroy the phase transition "extinct-alive", and the mutation amplitude is strongly influencing the value of the critical selection pressure. The phase diagram in the plane of the population's parameters -- selection and mutation is discussed as a function of the environmental variation characteristics. The differences between a smooth variation of the environment and an abrupt, catastrophic change are also addressesd.Comment: 15 pages, 12 figures. Accepted for publication in Phys. Rev.