El lamento de un matemático

Lamentablemente, nuestro sistema actual de educación matemática es precisamente este tipo de pesadilla. De hecho, si tuviese que diseñar un mecanismo con el único propósito de destruir la curiosidad natural y el amor a la creación de patrones de un niño, no podría hacer un trabajo mejor que el que se está haciendo actualmente —simplemente no tendría la imaginación necesaria para llegar al tipo de desalmadas e inconscientes ideas que constituyen la enseñanza de matemáticas contemporánea. Todo el mundo sabe que algo está mal. Los políticos dicen «necesitamos estándares más altos». Los institutos dicen «necesitamos más dinero y material». Los educadores dicen una cosa y los profesores otra. Todos están equivocados. Las únicas personas que entienden qué es lo que está pasando son a los que se les suele echar la culpa, y a los que menos se les escucha: los estudiantes. Ellos dicen «la clase de matemáticas es estúpida y aburrida», y es verdad

A meta-analysis of the impact of traffic-related air pollution on health and the factors affecting exposure

ISSN 1743-354

Geopolitics, Borders, and Federalism: Challenges for Post-War Iraq

The fall of the Ottoman Empire at the end of World War I enabled the victorious Western powers to implement the Sykes-Picot Treaty and reshape the geopolitical structure of the Middle East. The imposition of arbitrary borders on the Middle East region, specifically the state of Iraq, would lead to significant conflicts over the course of the 20th century. In 2003, a US-led invasion would further compound the instability and sectarian conflict within Iraq by completely dismantling the state. In the years after the invasion, the United States has been directly involved unsuccessfully in trying to rebuild and stabilize the state of Iraq. The goal of this study is to propose and analyze four options for the future geopolitical structure of Iraq that, by design, could maintain the current geopolitical borders and possibly contribute to stability in the Middle East. A qualitative approach that examines the benefits of different models of government is used to identify themes that may apply to the state of Iraq, Because adoption of any of the proposed options depends on choices that must be made by the Iraqi government, this thesis presents only a theoretical argument about the country’s likely future. It is my contention that the most likely route to achieving long-term political stability within Iraq is implementation of a federalist model of government that resembles the Swiss model. The Swiss model provides a framework to create ethnic tolerance through specific power devolution, internal cooperation, and conflict resolution between the different tribal and ethnic groups within each region, and external cooperation and adjudication of issues between the regions and the central government. This study’s results show that the different options analyzed all have positive and negative characteristics. The three-region Swiss model provided an exceptional framework and addressed a number of Iraq’s problems, but elements of the other models could be implemented into the three-region model to create a more stable state. Further analysis is needed to determine the best model of government to stabilize Iraq

Immune checkpoints and immunotherapy for colorectal cancer

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Freire Residential Training

Feedback forms from residential trainin

Differential gene transfers and gene duplications in primary and secondary endosymbioses

BACKGROUND: Most genes introduced into phototrophic eukaryotes during the process of endosymbiosis are either lost or relocated into the host nuclear genome. In contrast, groEL homologues are found in different genome compartments among phototrophic eukaryotes. Comparative sequence analyses of recently available genome data, have allowed us to reconstruct the evolutionary history of these genes and propose a hypothesis that explains the unusual genome distribution of groEL homologues. RESULTS: Our analyses indicate that while two distinct groEL genes were introduced into eukaryotes by a progenitor of plastids, these particular homologues have not been maintained in all evolutionary lineages. This is of significant interest, because two chaperone proteins always co-occur in oxygenic photosynthetic organisms. We infer strikingly different lineage specific processes of evolution involving deletion, duplication and targeting of groEL proteins. CONCLUSION: The requirement of two groEL homologues for chaperon function in phototrophs has provided a constraint that has shaped convergent evolutionary scenarios in divergent evolutionary lineages. GroEL provides a general evolutionary model for studying gene transfers and convergent evolutionary processes among eukaryotic lineages

Development of subfamily-based consensus PCR assays for the detection of human and animal herpesviruses

Consensus PCR assays that can be used to sensitively detect several herpesvirus (HV) species across the different subfamilies were developed in this study. Primers containing degenerate bases were designed to amplify regions of the DNA polymerase (DPOL) gene of alpha- and gamma-HVs, and the glycoprotein B (gB) gene of beta-HVs in a singleplex, non-nested touchdown PCR format. The singleplex touchdown consensus PCR (STC-PCR) was used to amplify the DNA of eight human and 24 animal HVs. The assay was able to detect the lowest DNA dilution of 10−5 for alpha-HVs and 10−3 for beta- and gamma-HVs. In comparison, lowest detection limits of 10−5, 10−3, and 10−2 were obtained for alpha-, beta-, and gamma-HVs respectively when a nested PCR was used. The findings in this study suggest that the STC-PCR assays can be employed for the molecular surveys and clinical detection of novel and known HVs

Development of subfamily-based consensus PCR assays for the detection of human and animal herpesviruses

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