Vaccination against the Influenza A virus (IAV) is often an important and critical task for much of the population, as IAV causes yearly epidemics, and can cause even deadlier pandemics. Designing the vaccine requires an understanding of the current major circulating strains of Influenza, as well as an understanding of how those strains could change over time to become either less harmful or more deadly, or simply die out completely. An error in the prediction process can lead to a non-immunized population at risk of epidemics, or even a pandemic. Presented here is a posterior predictive approach to generate emerging influenza strains based on a realistic genomic model that incorporates natural features of viral evolution such as selection and recombination. Also introduced is a sequence sampling scheme to relieve the computational burden of the posterior predictive analysis by clustering sequences based on their pairwise similarity. Finally, the impact of “evolutionary accidents” that take the form of bursts of evolution and or of recombination on the predictive power of our procedure is tested. An analysis of the impact of these bursts is carried out in a retrospective study that focuses on the unexpected emergence of a new H3N2 strain in the 2007-08 influenza season. Measuring the R2 values of both pairwise and patristic distances, the model reaches a predictive power of ∼40%, but is not able to simulate the emergence of the target Brisbane/10/2007 sequence with a high probability. The inclusion of “evolutionary accidents” improved the algorithm’s ability to predict HA sequences, but the prediction power of the NA gene remained low.

This work presents detailed analysis from the GEEC2 spectroscopic survey of galaxy groups at 0.8<z<1. This deep survey, which has a magnitude limit of r_AB<24.75, had previously found a population of intermediate ('green') galaxies between the star-forming ('blue') and quiescent ('red') sequences. GMOS-S spectroscopy for the 11 X-ray selected galaxy groups was obtained and is highly complete ( > 66 per cent) for eight of the eleven groups. Using an optical-NIR colour-colour diagram, the galaxies in the sample are separated with a dust insensitive method into the three categories, star-forming, quiescent, and intermediate. The strongest environmental dependence is observed in the fraction of quiescent galaxies, which is higher inside groups than in the field for all stellar masses. While intermediate galaxies represent ~15-20 per cent of the star-forming population in both the group and field, the average specific star formation rates (sSFR) of the group population is lower by a factor of ~3. The intermediate population also does not show the strong Hδ absorption that is characteristic of starburst galaxies. Inside groups, only 4.4-6.7 per cent of star-forming galaxies are starbursts, which gives additional validity to the assumption that the quenching of star-formation is the primary process in the transition from the star-forming to the quiescent state. With the use of stellar synthesis models, two possible scenarios for the origins of the intermediate population are investigated, including the quenching of star-forming galaxies via environmental processes and the rejuvenation of star formation in early-type galaxies via mixed mergers. To model the quenching scenario, we have tested the use of different exponential quenching timescales (τ_2) and different types of delays between satellite accretion and the onset of quenching. We found that the fraction of intermediate galaxies depends most strongly on the value of τ_2. The relative fractions of galaxies rule out both the no-delay scenario, which would require a long τ_2 that over-produces intermediate galaxies, as well as the constant 3 Gyr delay model, which does not produce a sufficient number of quiescent galaxies. The observed fractions are best matched with a model that includes a dynamical delay time and a τ_2=0.25 Gyr, but this model also predicts intermediate galaxies Hδ strength higher than that observed. For the rejuvenation scenario, we found that the time visible in the intermediate region is directly related to the size of the second 'burst' of star-formation, which can then be further constrained by the Hδ strength for the intermediate population. The observations are best matched to a burst size of ~1 per cent, at a rate of ~3 times per Gyr. In order to properly distinguish between the two scenarios, we will need to both increase the signal-to-noise ratio for the Hδ measurements and conduct a deeper survey of satellite galaxies both inside groups and in the field.

Studying nonnative species soon after their introduction is critical to understanding their risk of becoming widely invasive and determining effective methods of control. I conducted laboratory and field experiments on the Rasberry crazy ant (Paratrechina sp. nr. pubens), which was introduced to Pasadena, TX in 2002 and has since been spreading rapidly. These experiments focused on intraspecific aggression, as well as individual and colony-level interactions between crazy ants and red imported fire ants (Solenopsis invicta), which are dominant in the crazy ant's introduced range. Crazy ants displayed no intraspecific aggression. In individual aggressive encounters with fire ants, crazy ants had higher mortality than fire ants, but in colony-level clashes, crazy ants had less mortality and better control of food resources. These findings suggest that crazy ant abundance is key to their competitive success, and fire ants may provide biotic resistance to crazy ants in some areas.

The majority of typically sized galaxies in the local Universe reside in a common dark matter halo with other similar galaxies known as a galaxy group. However, this was not always the case. Nine billion years ago, when the universe was one third its current age, these galaxies were almost exclusively the only massive galaxy in their dark matter haloes. In this thesis, I use both observational and theoretical methods to attempt to understand the effect these galaxy groups have on the evolution of galaxy properties. I examine the morphological and star formation properties of galaxies in redshift selected samples of galaxy groups at two redshift epochs, z=0 and z=0.4. Galaxy groups contain fewer disk galaxies, as determined by quantitative morphology measures, than similar luminosity field galaxies at both redshift epochs. Furthermore, the difference, at fixed luminosity, grows from 6% at z=0.4 to 19% at z=0. The fraction of passive galaxies, as determined from spectral energy distribution fitting of UV and optical photometry, shows similar behaviour. However, at neither redshift do we find that the disk dominated and star forming galaxies in groups have properties which are significantly different from those in the field. The disks in both environments show similar scaling relations and similar distributions of asymmetry. While both group and field star forming galaxies have similar average star formation rates at fixed stellar mass and redshift. These results argue in favor of a relatively gentle physical mechanism of transformation, like strangulation, which removes the hot halo of a galaxy as it falls into a more massive halo. I use a semi-analytic galaxy formation to understand the accretion histories of galaxies which reside in galaxy groups and clusters at different redshift epochs. The use of a simple model for environmental effects finds that the evolution seen in our observations of passive galaxies can be explained if a galaxy becomes passive 3 Gyrs after falling into a dark matter halo which has a mass of greater than 10E13 Msun. Finally, I use two novel methods for exploring how diffuse stellar mass and dust is distributed in and around galaxy groups. These are important probes of the environmental influence on galaxy evolution. By correlating the positions of hostless type Ia supernovae with galaxy groups, I find that as much as half of a galaxy's stellar mass is in a diffuse form outside of galaxies. These means that processes which shred or harass galaxies must be particularly strong in the group environment. I also find that dust is destroyed by the hot gas contained within groups and clusters. Dust is a necessary component of star formation, and its destruction could be an additional mechanism to suppress the production of stars in galaxy groups.

The jealousy derives from the interaction of difference and comparison. It is mainly reflected in wealth, reputation, status and love. This study reveals what¡¦s the dominant strategy and who can survive in the society via game theory to analyze and describe the result of the interaction between a jealous one and his rival for wealth on the different levels of jealousy. It is found as below: (1).Whether the jealous person takes offensive action or not, he will receive the most harm or punishment; so it is a dominant strategy for him. (2). If someone tortures by themselves, he will suffer misery from jealousy; so it is a dominant strategy for him. (3). If the jealous person desires to catch up with his rivals via honest means, he will turn jealousy into competitive ability; as a result, those that have opposite intention will gradually be eliminated through competition. (4). If the jealous person defames, or even attacks his rivals, and attempts to benefit from them, it is happened that the extra return will make up for the cost based on jealousy; consequently it is a dominant strategy so that they will be replaced step by step.

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The Ucayali Basin is a Peruvian sub-Andean basin that initially formed during the extensive tectonics of the Early Paleozoic. Originally, the Ucayali Basin was part of a larger basin that extended east of the current Andean chain along the Peruvian territory. Subsequently, this large basin was divided into many smaller sub-Basins during the Andean Orogeny. Today, the basin covers an area of about 140,000 km2, and it is morphologically defined by two well-differentiated structural features: the sub- Andean fold and thrust belt (SFTB) to the west and the Amazon plain and Brazilian shield to the east. It is limited to the north and south by the Contaya and Fitzcarrald Arches respectively, the Andes to the west and the Brazilian Shield to the east. These structural features acted as favorable elements to add sediments and to contribute to the structural development of this basin. The sedimentary section of the basin varies in thickness from 1 to 10 km, with ages of strata ranging from the Paleozoic to Quaternary. The strata were deposited in deep and shallow marine as well as transitional and fluvial continental environments. The most important phase of marine sedimentation was initiated with the transgression of the Cretaceous sea (Aptian –Albian) over the irregular paleogeography defined by morphologic highs and peneplains. Tectonic features of the basin show structural deformations parallel to the Andean front, where overturned structures are observed. These are commonly cut by thrusts and laterally displaced by strike-slip faults. To better understand the development of the Shira Mountains in the central part of the Ucayali Basin, the structural and stratigraphic relationships were mapped out using a dense grid of 2D seismic reflection data and well log control. Three regional EW cross sections were constructed and restored to the top of the Cretaceous to determine the nature of deformation and faulting during the Paleozoic and Mesozoic. The reconstructions show that Shira Mountains fault was initially a major normal fault bounding a half graben. The fault was reactivated by later compression as a thick-skinned thrust fault that detaches between 21 and 24 km depth. Reactivation occurred during Upper Miocene between 7.2 and 5.3 Ma, corresponding to the Quechua 3 compressive phase of Andean Orogeny. The shortening of the central Ucayali Basin determined by the reconstructed cross sections ranges between 3 and 5.5%.

Most of genes contained in a genome have been shown to exist in forms of families; however, little is known about their variation and evolution during the course of genome evolution. The present study shows that the numbers of the genes of the NBS-LRR-encoding gene family vary extremely significantly among different lines or cultivars of a species and among related species from the same genus. This suggests that plant genetics and evolution depend on not only gene sequence variation, but also the number of genes in multigene families. This study has further revealed that the variation of number of genes in the gene family in the Gossypium species is affected significantly not only by genome size variation, polyploidization and natural selection, but also by domestication/breeding. There is a positive correlation (P less than or equal to 0.05) between genome size and number of genes in the family, suggesting that species with larger genomes tend to have more NBS-LRR-encoding genes. It was observed that natural polyploids have significantly larger numbers of genes in the family and larger genomes than the artificial polyploids of their putative diploid ancestors. This indicates that polyploidization, perhaps post-polyploidization as well, either led to the loss of the genes in a gene family or slowed the process of gene number increase after polyploidization. It was shown that cultivated cottons have significantly more NBSLRR- encoding genes than wild species at both diploid and polyploidy levels. This result indicates that plant breeding likely allows accumulation of NBS-LRR-encoding genes that potentially provide resistance to pathogens. Therefore, plant breeders have selected not only for favorable alleles and favorable allele combinations, but also for the number of genes. Finally, difference (P less than or equal to 0.001) was found in number of genes in the NBS-LRR-encoding gene family among the species native to different geographical regions, suggesting that natural selection has played an important role in the variation in number of genes in the NBS-LRR-encoding gene family. The gene members that are favorable for fitness at the time are selected and accumulated in the genomes, but those that are not favorable for fitness at the time are lost in natural selection. As this is the first study in the field, further studies remain. These include, but not limited to, the universality of the findings in plants and animals, the universality of the findings in different gene families, genetics of the gene family size variation, relationship between the gene family size variation and phenotypic variation, gene family size variation and breeding, etc. Nevertheless, the findings obtained from this study are sufficient to shed light on many fundamental questions in biology, diversity and complexity of plants and animals.

The determinants of multinational corporation subsidiaries' role and evolution--An empirical study of MNC subsidiary in Taiwan.My paper contains five companies to study the subsidiaries' strategic role and evolution.