Neutrino dispersion relation in a magnetized multi-stream matter background

We study the propagation of a neutrino in a medium that consists of two or more thermal backgrounds of electrons and nucleons moving with some relative velocity, in the presence of a static and homogeneous electromagnetic field. We calculate the neutrino self-energy and dispersion relation using the linear thermal Schwinger propagator, we give the formulas for the dispersion relation and discuss general features of the results obtained, in particular the effects of the stream contributions. As a specific example we discuss in some detail the case of a magnetized two-stream electron, i.e., two electron backgrounds with a relative velocity $\vec v$ in the presence of a magnetic field. For a neutrino propagating with momentum $\vec k$, in the presence of the stream the neutrino dispersion relation acquires an anisotropic contribution of the form $\hat k\cdot\vec v$ in addition to the well known term $\hat k\cdot\vec B$, as well as an additional contribution proportional to $\vec B\cdot\vec v$. We consider the contribution from a nucleon stream background as an example of other possible stream backgrounds, and comment on possible generalizations to take into account the effects of inhomogeneous fields. We explain why a term of the form $\hat k\cdot(\vec v\times\vec B)$ does not appear in the dispersion relation in the constant field case, while a term of similar form can appear in the presence of an inhomogeneous field involving its gradient.Comment: Title changed, 21 pages, 1 figur

Diagnostico Estratégico de Nicaragua Christian Academia, ciudad de Matagalpa, II Semestre 2014

El siguiente documento se realizó con el fin de realizar un “Diagnóstico Estratégico en Nicaragua Christian Academia en el segundo semestre del 2014, con la finalidad determinar la situación actual del colegio. El propósito de la investigación es proporcionar una herramienta útil para mejorar el desempeño organizacional de NCA, ya que le permitirá conocer su situación como empresa y su posición frente a la competencia. Cabe señalar que es de mucha importancia realizar un diagnostico estratégico para lograr identificar el estado de salud que se encuentra la empresa para identificar los problemas y darles soluciones. También será de utilidad para otros empresarios, así como para consultas bibliográficas y además enriquecer los conocimientos de las investigadoras. Con el diagnóstico estratégico realizado se logró comprobar que NCA tiene definida su filosofía, siendo una gran fortaleza, que prestan un servicio de calidad, en condiciones y ambiente apropiado para brindar un servicio educativo diferenciado. También se logro identificar que han implementado la estrategias de diferenciación y operaciones conjuntas, en base a las fortalezas y oportunidades de crecimiento en el mercado, así como las capacidades con que cuentan, se propone valorar la implementación de las estrategias de desarrollo de producto, desarrollo de mercado, recorte de gastos, innovación, que le ayudan a posicionarse y ser más competitivo. Las que al mismo tiempo le ayudaran a superar las debilidades que enfrentan como son barreras administrativas, comunicación e infraestructur

Riverside’s Chinatown

The City of Riverside has benefited economically, culturally, socially, and historically through the diverse contributions of Chinese immigrants. In the nineteenth and twentieth century, Chinese immigrants contributed by making Riverside an economic powerhouse through its citrus industry. Riverside’s Chinatown, which once was populated and flourished by thousands of Chinese bachelors during harvest season, has been deserted and neglected over the past several decades. The site where Riverside’s Chinatown once stood is one of the richest sites of Chinese American artifacts in the United States, yet is currently under threat for being destroyed to make way for new development

Motherhood Through the Lens of Medieval Japanese Ghosts

This paper examines the relationship between late-Heian and early-Kamakura Japanese motherhood and Buddhist gaki or hungry ghosts. It highlights the physical, emotional, and spiritual burdens faced by mothers, emphasizing their role in the cycle of rebirth. Drawing from the diaries of aristocratic women, the paper illuminates the emotional and societal challenges faced by women in a patriarchal society. It highlights how women were often seen as more likely to be reborn as gaki due to gendered stereotypes and how motherhood was revered while simultaneously being tarnished

Factors that Influence the Choice to Major in STEM for Latino and non-Latino Students and Professionals

Latinos are the largest minority group in the United States, with 18.5 percent of the nation’s population. However, when it comes to Latinos in STEM, they represent only 8 percent of all STEM workers. This disparity can be largely traced to disproportionally low numbers in graduation rates in high school and college, in conjunction with the lack of exposure to STEM fields and access to rigorous K-12 curriculums associated with STEM pathways. The survey incorporated into this research investigates which factors influence Latinos in choosing a STEM major. The survey questions focused on high school academics, parental educational attainment, home support and previous perceptions about mathematics and sciences. The results were analyzed by comparing the Latino demographic to the White demographic. The data gathered contributes to the research found that high school performance is a strong indicator for going into a STEM field given that the average GPA of both groups were very high. There was a difference of five points when it came to the average ACT score. The results showed a significant difference in parental education between both groups. Most notably, contrary to research, most Latinos had access to AP or advance courses in high school. Every student who had access to advanced courses enrolled in them. To further bring awareness of the issues at hand and to further stimulate the discussion of this topic an open-access website was created to provide access and awareness to the data gathered

Large neighborhood search for the most strings with few bad columns problem

In this work, we consider the following NP-hard combinatorial optimization problem from computational biology. Given a set of input strings of equal length, the goal is to identify a maximum cardinality subset of strings that differ maximally in a pre-defined number of positions. First of all, we introduce an integer linear programming model for this problem. Second, two variants of a rather simple greedy strategy are proposed. Finally, a large neighborhood search algorithm is presented. A comprehensive experimental comparison among the proposed techniques shows, first, that larger neighborhood search generally outperforms both greedy strategies. Second, while large neighborhood search shows to be competitive with the stand-alone application of CPLEX for small- and medium-sized problem instances, it outperforms CPLEX in the context of larger instances.Peer ReviewedPostprint (author's final draft

The Loss of Ecological Knowledge: A look into the FDA Organic Label Movement and its effects on Local Communities

Organic agriculture is an emerging market sector in USDA agricultural business. The majority of those who take organic labeling into consideration when they are purchasing their food products from stores have some idea about the USDA certified organic label on the product’s packaging, however, there is also much left unknown. What is this label and how does one get an organic certification? In this project, I am researching the organic certification process and larger ethical questions regarding the human relationship with nature and foodstuffs. In particular, I will be exploring the erosion of local ecological knowledge and how this can impact understanding of the “organic” standard. Organic certification currently is limited by the USDA to those farmers and producers who can produce a specific quantity of goods to sell and neglects those who are serving their communities in farmers markets and other local communities. In order to fix this, ensuring the resources of the USDA are actually reaching these communities is vital for the expansion of organic certification and labeling and the maintenance of local ecological knowledge in the United States. This project will explore the tensions between economic, social, and environmental well-being in the context of organic food and management practices for sustainability