Economic Mobility: Is the American Dream Alive and Well?

Draws on research analysis to outline what economic mobility is, why it matters in today's economy, and why it is important for policy makers to focus on mobility as part of the ongoing national economic debate

Altering an extended phenotype reduces intraspecific male aggression and can maintain diversity in cichlid fish

Reduced male aggression towards different phenotypes generating negative frequency-dependent intrasexual selection has been suggested as a mechanism to facilitate the invasion and maintenance of novel phenotypes in a population. To date, the best empirical evidence for the phenomenon has been provided by laboratory studies on cichlid fish with different colour polymorphisms. Here we experimentally tested the hypothesis in a natural population of Lake Malawi cichlid fish, in which males build sand-castles (bowers) to attract females during seasonal leks. We predicted that if bower shape plays an important role in male aggressive interactions, aggression among conspecific males should decrease when their bower shape is altered. Accordingly, we allocated randomly chosen bowers in a Nyassachromis cf. microcephalus lek into three treatments: control, manipulated to a different shape, and simulated manipulation. We then measured male behaviours and bower shape before and after these treatments. We found that once bower shape was altered, males were involved in significantly fewer aggressive interactions with conspecific males than before manipulation. Mating success was not affected. Our results support the idea that an extended phenotype, such as bower shape, can be important in maintaining polymorphic populations. Specifically, reduced male conspecific aggression towards males with different extended phenotypes (here, bower shapes) may cause negative frequency-dependent selection, allowing the invasion and establishment of a new phenotype (bower builder). This could help our understanding of mechanisms of diversification within populations, and in particular, the overall diversification of bower shapes within Lake Malawi cichlids

Pax1 and Pax9 activate Bapx1 to induce chondrogenic differentiation in the sclerotome.

We have previously shown that the paired-box transcription factors Pax1 and Pax9 synergistically act in the proper formation of the vertebral column. Nevertheless, downstream events of the Pax1/Pax9 action and their target genes remain to be elucidated. We show, by analyzing Pax1;Pax9 double mutant mice, that expression of Bapx1 in the sclerotome requires the presence of Pax1 and Pax9, in a gene dose-dependent manner. By using a retroviral system to overexpress Pax1 in chick presomitic mesoderm explants, we show that Pax1 can substitute for Shh in inducing Bapx1 expression and in initiating chondrogenic differentiation. Furthermore, we demonstrate that Pax1 and Pax9 can transactivate regulatory sequences in the Bapx1 promoter and that they physically interact with the Bapx1 promoter region. These results strongly suggest that Bapx1 is a direct target of Pax1 and Pax9. Together, we conclude that Pax1 and Pax9 are required and sufficient for the chondrogenic differentiation of sclerotomal cells

DYNAMIC FACTORS INFLUENCING U.S. AND REGIONAL CATFISH DEMAND

Response to changes in factors influencing consumption of catfish and competing commodities differ between national, South Atlantic, and Southwest Central markets. A modified state adjustment model for catfish, beef, chicken, and other fish explicitly included age distribution, residence, occupation, education, and race/ethnic variables associated with habit formation. Nationally, per capita expenditures on catfish respond to present and past relative prices, and catfish, chicken, and other fish, but not beef, consumption demonstrates significant habit formation. South Atlantic and Southwest Central habits for catfish consumption persist, and, as the population ages, chicken and fish consumption increase.Demand and Price Analysis,

Social Interactions and Fertility in Developing Countries

There is strong evidence that, in addition to individual and household characteristics, social interactions are important in determining fertility rates. Social interactions can lead to a multiplier effect where an individual’s ideas, and fertility choice, can affect the fertility decisions of others. We merge all available Demographic and Health Surveys to investigate the factors that influence both individual and average group fertility. We find that in the early phase of the fertility transition the impact of a woman’s education and experience of child death on her group’s average fertility are more than three times as large as their direct effect on her own fertility decision.demography, growth, age structure, population, economy.

Entanglement invariant for the double Jaynes-Cummings model

We study entanglement dynamics between four qubits interacting through two isolated Jaynes-Cummings hamiltonians, via the entanglement measure based on the wedge product. We compare the results with similar results obtained using bipartite concurrence resulting in what is referred to as "entanglement sudden death". We find a natural entanglement invariant under evolution demonstrating that entanglement sudden death is caused by ignoring (tracing over) some of the system's degrees of freedom that become entangled through the interaction.Comment: Sec. V has largely been rewritten. An error pertaining to the entanglement invariant has been corrected and a correct invariant valid for a much larger set of states have been found, Eq. (25

Au-Cu/SBA(Ti) based catalysts for photocatalytic applications

Comunicación a congresoIn this work, it has been synthesized several Au and Au-Cu alloy photocatalysts supported on two different mesoporous supports: a non-commercial SBA-15 and a post-synthesis TiO2 modified SBA-15 (TiSBA-15), with which a high dispersion of TiO2 species have been achieved maintaining the SBA-15 structure. In addition, it has also been obtained highly dispersed Au nanoparticles confined in SBA-15 pore channels, as can be observed in Figure 1. The photocatalysts have been preliminary tested in the preferential CO oxidation in a H2-rich stream (CO-PROX) at room temperature and atmospheric pressure under simulated solar light irradiation. In spite of the very low gold and copper loading (1.5 wt% and 0.5wt% respectively), the catalysts resulted active and selective in the low temperature photo-CO-PROX.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tec

Impact of tumor-specific targeting on the biodistribution and efficacy of siRNA nanoparticles measured by multimodality in vivo imaging

Targeted delivery represents a promising approach for the development of safer and more effective therapeutics for oncology applications. Although macromolecules accumulate nonspecifically in tumors through the enhanced permeability and retention (EPR) effect, previous studies using nanoparticles to deliver chemotherapeutics or siRNA demonstrated that attachment of cell-specific targeting ligands to the surface of nanoparticles leads to enhanced potency relative to nontargeted formulations. Here, we use positron emission tomography (PET) and bioluminescent imaging to quantify the in vivo biodistribution and function of nanoparticles formed with cyclodextrin-containing polycations and siRNA. Conjugation of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid to the 5' end of the siRNA molecules allows labeling with 64Cu for PET imaging. Bioluminescent imaging of mice bearing luciferase-expressing Neuro2A s.c. tumors before and after PET imaging enables correlation of functional efficacy with biodistribution data. Although both nontargeted and transferrin-targeted siRNA nanoparticles exhibit similar biodistribution and tumor localization by PET, transferrin-targeted siRNA nanoparticles reduce tumor luciferase activity by {approx}50% relative to nontargeted siRNA nanoparticles 1 d after injection. Compartmental modeling is used to show that the primary advantage of targeted nanoparticles is associated with processes involved in cellular uptake in tumor cells rather than overall tumor localization. Optimization of internalization may therefore be key for the development of effective nanoparticle-based targeted therapeutics

Electric Scooter Injuries and Hospital Admissions in the United States, 2014-2018.

This study investigates trends of injury and hospital admission associated with electric scooter use