The Hetu'u Global Network: Measuring the Distance to the Sun Using the June 5th/6th Transit of Venus

In the spirit of historic astronomical endeavors, we invited school groups across the globe to collaborate in a solar distance measurement using the rare June 5/6th transit of Venus. In total, we recruited 19 school groups spread over 6 continents and 10 countries to participate in our Hetu'u Global Network. Applying the methods of French astronomer Joseph-Nicolas Delisle, we used individual second and third Venus-Sun contact times to calculate the distance to the Sun. Ten of the sites in our network had amiable weather; 8 of which measured second contact and 5 of which measured third contact leading to consistent solar distance measurements of 152+/-30 million km and 163+/-30 million km respectively. The distance to the Sun at the time of the transit was 152.25 million km; therefore, our measurements are also consistent within 1sigma of the known value. The goal of our international school group network was to inspire the next generation of scientists using the excitement and accessibility of a rare astronomical event. In the process, we connected hundreds of participating students representing a diverse, multi-cultural group with differing political, economic, and racial backgrounds.Comment: 19 pages; 7 Figures; 1 Table; Accepted for publication in Astronomy Education Review (AER) For more information see http://www.das.uchile.cl/~drodrigu/easter/index_en.htm

ROLE OF OXIDATIVE STRESS AND T CELL HOMING IN THE DEVELOPMENT OF MURINE SYNGENEIC GRAFT-VERSUS-HOST DISEASE

Syngeneic graft-versus-host disease (SGVHD) is induced by reconstituting lethally irradiated mice with syngeneic BM cells followed by a 21 day treatment with the immunosuppressive agent cyclosporine A (CsA). Clinical symptoms of the disease appear 2-3 weeks following cessation of CsA therapy and disease-associated inflammation occurs primarily in the colon and liver. The development of SGVHD is a complex process resulting from the cooperative interaction of multiple effector cell populations including NK cells, T cells and macrophages. TH1 cytokines (IL-12, TNF-α, IFN- γ), produced by these effector cells, serve as inflammatory mediators contributing to the pathogenesis of SGVHD. The SGVHD conditioning agents, irradiation and CsA, are both required for the development of disease and contribute to the production of oxidative stress. Time course studies revealed increased reactive oxygen and nitrogen species (ROS/RNS), as well as, increased colon mRNA levels for TNF-α and iNOS in CsA-treated versus control BMT animals. Since ROS/RNS are known to mediate CsA toxicity, studies were undertaken to determine the effect of oxidative stress on the induction of SGVHD. In vivo treatment with the antioxidant MnTBAP caused a reduction in colon mRNA levels for iNOS and TNF-α, as well as delayed disease development, suggesting a role for oxidative stress in the development of SGVHD. In addition, CD4+ T cells have been shown to play an important role in the inflammatory response observed in the gut of SGVHD mice. Time course studies revealed significant increases in the migration of CD4+ T cells as early as day 14 post- BMT into the colon of CsA mice as well as significant elevated mRNA levels of cell adhesion molecules. Homing studies revealed that a labeled CD4+ T cell line, generated from SGVHD mice, migrated in larger numbers into the gut of CsA-treated mice compared to control animals. This study demonstrated that CD4+ T cells responsible for the pathogenesis observed in murine SGVHD are present early after BMT in colons of CsA-treated mice, suggesting that during the 21 days of immunosuppression therapy functional mechanisms are in place that result in increased homing of effector cells to colons of CsA-treated mice

An Examination Of Inclusive Education In Schools Operated By The Jordan Field Of The United Nations Relief And Works Agency For Palestine Refugees In The Near East

For refugee children with disabilities, international agencies largely provide humanitarian assistance, including education. However, the obstacles associated with refugee existence can impede progress in the movement towards educating children with disabilities in inclusive settings. Perceptions of inclusive education in schools operated by the Jordan field of the United Nations Relief and Works Agency for Palestine Refugees in the Near East were explored through multiple embedded case studies. Each of the three schools examined included a student with a special educational need. The researcher also investigated strategies and supports provided by education stakeholders to students with special educational needs in inclusive classrooms. The study was framed by four research questions aligned to a theoretical model of inclusive education and guided by propositions. Findings from interviews, classroom observations, and document reviews, suggest that all stakeholders believe education for students with special educational needs is a human right. However, perceptions of inclusion differed based on several factors including the student’s level of need and the disability, the teacher’s self-efficacy and feeling of preparedness towards meeting the needs of students, and the impact of overcrowded classrooms and limited instructional time. In comparing results between stakeholders, differences existed in perceptions of benefits and challenges associated with inclusive education

Strategies for Cryptocurrency Adoption in Contemporary Businesses

Millions of Bitcoin transactions occur daily, worth nearly $2 billion annually. With the proliferation of cryptocurrency markets, the reluctance to adopt the currency as an alternate payment method could cause businesses to forgo growth opportunities within this expanding market. Grounded in the diffusion of innovation theory, the purpose of this qualitative multiple-case study was to explore strategies business leaders use to respond to the alternative payment concerns perpetuated by cryptocurrency markets. The participants comprised 6 business leaders who effectively employed cryptocurrency adoption strategies. Data were collected through semistructured interviews, corporate documents, and other company social media resources. Thematic analysis of the data resulted in 4 common themes: commitment to innovation as a relative advantage, cryptocurrency compatibility within the organization, overcoming the complexity of cryptocurrency adoption, and trialability and observability of innovative technology. Key recommendations include creating business models to encourage more cryptocurrency transaction-based outcomes and creating cryptocurrency education and training programs for employees and customers. The implications for positive social change include the potential to assist unbanked individuals who lack creditworthiness to gain access to more goods and services to improve their overall standard of living

Using Clickers in Large College Psychology Classes: Academic Achievement and Perceptions

This research study explored the effects of the use of clicker technology as a means of formative assessment in large, college introductory psychology courses. Academic achievement, as measured by performance on tests of knowledge, was compared between students who used clickers and students that did not use clickers. There was a significant difference between the two groups, although a small effect was noted. Students using the clickers responded to survey items created to solicit information regarding student perceptions of increased understanding, ability to self-identify content deficits, fun, and financial value of clickers. Data from the survey indicated that the majority of students perceived the usage of clickers increased their understanding of and ability to self-identify concept areas. All of the students reported that using clickers was fun, although approximately only one third of those same students reported that purchasing a clicker was worthwhile. Implications for administrators are discussed and alternative technologies are explored

Efecto del sobrepeso y la obesidad en la actividad de las enzimas antioxidantes en testículo y epidídimo de rata Wistar

La obesidad es un problema de salud mundial, el cual ha ido en aumento en los últimos años, y se le ha asociado con diversas alteraciones, entre las cuales se mencionan las cardiopatías, cáncer, diabetes, problemas metabólicos, así como, la infertilidad masculina, debido a que se han presentado casos de hombres obesos con problemas de subinfertilidad y alteración en los parámetros espermáticos, razón por la cual ha llevado a distintos investigadores a estudiar la relación entre el índice de masa corporal (IMC) y la calidad seminal, reportando que durante la obesidad se genera un incremento de tejido adiposo el cual es capaz de inducir alteraciones endocrinas y físicas. A pesar de esto pocos estudios le han dado importancia al sobrepeso, de tal modo que se desconoce si ya en estados fisiológicos de sobrepeso se suscitan cambios que pudieran causar modificaciones en los factores hormonales y físicos. Por otro lado, se sabe que, en estados fisiológicos normales, las especies reactivas de oxigeno (EROs) se encuentran presentes en todas las células, las cuales son moléculas que tienen la capacidad de actuar como segundos mensajeros estimulando respuestas como la supervivencia, pero cuando estas moléculas sobrepasan concentraciones fisiológicas normales se genera estrés oxidante que trae consigo daño o muerte celular. Para contrarrestar el posible efecto nocivo de EROs, está presente el sistema enzimático antioxidante, el cual se compone de: superóxido dismutasa (SOD), catalasa (CAT) y glutatión peroxidasa (GPx). Debido a la importancia que cumplen estas enzimas antioxidantes como agentes protectores para las células, es de relevancia conocer si están implicadas en la protección en el tracto reproductor masculino, pues poco se ha descrito en cuanto a las alteraciones físicas implicadas en la obesidad y hasta el momento se desconoce si el incremento de tejido adiposo en la zona escrotal, pudiese alterar la actividad enzimática antioxidante y también se desconoce cuáles antioxidantes se encargan de brindar protección. Por ello en este trabajo se plantea que al inducir sobrepeso u obesidad por una dieta hiperlipídica, se verá alterada la función de las enzimas antioxidantes en el testículo y epidídimo de la rata Wistar, como respuesta ante el posible estrés oxidante. Paralo cual, se evaluaron parámetros espermáticos de viabilidad y morfología en el semen de ratas Wistar, a las cuales se les administró una dieta hiperlipídica al 10% y 60% de grasas y se encontró que el porcentaje de espermatozoides vivos se ve disminuido en los grupos de sobrepeso y obesidad con respecto al grupo control, además de que se presentó un incremento en las anormalidades del espermatozoide principalmente de pieza media, flagelo angulado y enrollado en los grupos de sobrepeso y obesidad con respecto al grupo control. En cuanto a la actividad específica de las enzimas antioxidantes: SOD, CAT y GPx, se obtuvo un aumento en las actividades enzimáticas de los antioxidantes para los grupos de ratas con sobrepeso y obesidad comparado con los controles que recibieron una dieta balanceada, estos resultados indican que probablemente se debe a un incremento en la producción de ERO en los estados fisiológicos de sobrepeso y obesidad, como un intento por proteger a las células contra el daño oxidativo. Por tanto, el sistema de protección enzimático antioxidante es eficiente al proteger contra el daño de EROs, siendo las condiciones de sobrepeso y obesidad factores que pueden inducir subfertilidad, al comenzar a presentarse daños en la calidad espermática

Scholarship of Teaching and Learning: Developing a Culture of Assessment

The Scholarship of Teaching and Learning Initiative at Hostos Community College focuses on melding assessment and faculty development through a scholastic approach. In order to facilitate a campus-wide engagement in assessment, particularly related to the effectiveness of classroom instruction, the focus remains on individual expectations and talents, professional responsibilities, and using formative and summative assessment to improve student success and recidivism. This was initiated through open dialogue on the critical need for inquiry-based instruction, targeted presentations, and a sustainable network of support