174 research outputs found
Recommended from our members
Nevada Test Site Perspective on Characterization and Loading of Legacy Transuranic Drums Utilizing the Central Characterization Project
The Nevada Test Site (NTS) has successfully completed a multi-year effort to characterize and ship 1860 legacy transuranic (TRU) waste drums for disposal at the Waste Isolation Pilot Plant (WIPP), a permanent TRU disposal site. This has been a cooperative effort among the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), the U.S. Department of Energy, Carlsbad Field Office (DOE/CBFO), the NTS Management and Operations (M&O) contractor Bechtel Nevada (BN), and various contractors under the Central Characterization Project (CCP) umbrella. The success is due primarily to the diligence, perseverance, and hard work of each of the contractors, the DOE/CBFO, and NNSA/NSO, along with the support of the U.S. Department of Energy, Headquarters (DOE/HQ). This paper presents, from an NTS perspective, the challenges and successes of utilizing the CCP for obtaining a certified characterization program, sharing responsibilities for characterization, data validation, and loading of TRU waste with BN to achieve disposal at WIPP from a Small Quantity Site (SQS) such as the NTS. The challenges in this effort arose from two general sources. First, the arrangement of DOE/CBFO contractors under the CCP performing work and certifying waste at the NTS within a Hazard Category 2 (HazCat 2) non-reactor nuclear facility operated by BN, presented difficult challenges. The nuclear safety authorization basis, safety liability and responsibility, conduct of operations, allocation and scheduling of resources, and other issues were particularly demanding. The program-level and field coordination needed for the closely interrelated characterization tasks was extensive and required considerable effort by all parties. The second source of challenge was the legacy waste itself. None of the waste was generated at the NTS. The waste was generated at Lawrence Livermore National Laboratory (LLNL), Lawrence Berkeley Laboratory (LBL), Lynchburg, Rocky Flats Environmental Technology Site (RFETS), and a variety of other sites over 20 years ago, making the development of Acceptable Knowledge a significant and problematic effort. In addition, the characterization requirements, and data quality objectives for shipment and WIPP disposal today, were non-existent when this waste was generated, resulting in real-time adjustments to unexpected conditions
JOGO EDUCATIVO PARA A DISCIPLINA DE GEOGRAFIA
This paper discusses the project of an educational game that was developed for the discipline of geography. Currently the educational games are increasingly being used inside schools in order to bring the play to the learning environment, making the lessons more enjoyable and aiding the process of teaching and learning. The idea to develop this game of Geography is to encourage children to learn more about this discipline, through games like puzzle games, memory games, questions and answers among others, that address various issues in Brazil and the world
JOGO EDUCATIVO PARA A DISCIPLINA DE GEOGRAFIA
Este artigo discorre sobre o projeto de um jogo educativo que foi desenvolvido para a disciplina de geografia. Atualmente os jogos educacionais estão sendo cada vez mais usados dentro das escolas com o objetivo de levar o lúdico para o ambiente de aprendizado, tornando as aulas mais agradáveis e auxiliando o processo de ensino aprendizagem. A idéia ao se desenvolver este jogo de Geografia é incentivar as crianças a aprenderem mais sobre esta disciplina, através de jogos como quebra-cabeça, jogos de memória, jogos de perguntas e respostas entre outros, que abordam vários assuntos do Brasil e do mundo
Recommended from our members
Safety Assessment for Explosive Risk (SAFER) peer review report.
At the direction of the Department of Defense Explosives Safety Board (DDESB), a Peer Review Team was established to review the status of development of the risk-based explosives safety siting process and criteria as currently implemented in the software 'Safety Assessment for Explosive Risk (SAFER)' Version 2.1. The objective of the Peer Review Team was to provide an independent evaluation of the components of the SAFER model, the ongoing development of the model and the risk assessment process and criteria. This peer review report addressed procedures; protocols; physical and statistical science algorithms; related documents; and software quality assurance, validation and verification. Overall, the risk-based method in SAFER represents a major improvement in the Department of Defense (DoD) approach to explosives safety management. The DDESB and Risk Based Explosives Safety Criteria Team (RBESCT) have made major strides in developing a methodology, which over time may become a worldwide model. The current status of all key areas of the SAFER code has been logically developed and is defensible. Continued improvement and refinement can be expected as implementation proceeds. A consistent approach to addressing and refining uncertainty in each of the primary areas (probability of event, consequences of event and exposure) will be a very beneficial future activity
Spontaneous corneal melting in pregnancy: a case report
<p>Abstract</p> <p>Background</p> <p>To report a case of spontaneous corneal melting in pregnancy. We reviewed the literature on corneal melting and the effect of pregnancy on cornea and collagen containing tissues.</p> <p>Case presentation</p> <p>A 29-year-old woman who underwent radial keratotomy in both eyes followed by trabeculectomy in her left eye developed corneal melting in the same eye, in her seventh month of pregnancy. Despite screening, no infectious or immune mediated condition could be identified. She was managed conservatively with cyanoacrylate glue, bandage contact lens, lubricants and antibiotics.</p> <p>Conclusion</p> <p>It may not always be possible to find the underlying cause of corneal melting but the more common underlying causes should be ruled out by proper investigations. Pregnancy with its host of hormonal changes could potentially have some effect on corneal collagen leading to corneal melting in compromised corneas.</p
Putative IKDCs are functionally and developmentally similar to natural killer cells, but not to dendritic cells
Interferon-producing killer dendritic cells (IKDCs) have been described as possessing the lytic potential of NK cells and the antigen-presenting capacity of dendritic cells (DCs). In this study, we examine the lytic function and antigen-presenting capacity of mouse spleen IKDCs, including those found in DC preparations. IKDCs efficiently killed NK cell targets, without requiring additional activation stimuli. However, in our hands, when exposed to protein antigen or to MHC class II peptide, IKDCs induced little or no T cell proliferation relative to conventional DCs or plasmacytoid DCs, either before or after activation with CpG, or in several disease models. Certain developmental features indicated that IKDCs resembled NK cells more than DCs. IKDCs, like NK cells, did not express the transcription factor PU.1 and were absent from recombinase activating gene-2–null, common γ-chain–null (Rag2−/−Il2rg−/−) mice. When cultured with IL-15 and -18, IKDCs proliferated extensively, like NK cells. Under these conditions, a proportion of expanded IKDCs and NK cells expressed high levels of surface MHC class II. However, even such MHC class II+ IKDCs and NK cells induced poor T cell proliferative responses compared with DCs. Thus, IKDCs resemble NK cells functionally, and neither cell type could be induced to be effective antigen-presenting cells
Plasmodium berghei Hsp90 contains a natural immunogenic I-A<sup>b</sup>-restricted antigen common to rodent and human Plasmodium species
Thorough understanding of the role of CD4 T cells in immunity can be greatly assisted by the study of responses to defined specificities. This requires knowledge of Plasmodium-derived immunogenic epitopes, of which only a few have been identified, especially for the mouse C57BL/6 background. We recently developed a TCR transgenic mouse line, termed PbT-II, that produces CD4+ T cells specific for an MHC class II (I-Ab)-restricted Plasmodium epitope and is responsive to both sporozoites and blood-stage P. berghei. Here, we identify a peptide within the P. berghei heat shock protein 90 as the cognate epitope recognised by PbT-II cells. We show that C57BL/6 mice infected with P. berghei blood-stage induce an endogenous CD4 T cell response specific for this epitope, indicating cells of similar specificity to PbT-II cells are present in the naïve repertoire. Adoptive transfer of in vitro activated TH1-, or particularly TH2-polarised PbT-II cells improved control of P. berghei parasitemia in C57BL/6 mice and drastically reduced the onset of experimental cerebral malaria. Our results identify a versatile, potentially protective MHC-II restricted epitope useful for exploration of CD4 T cell-mediated immunity and vaccination strategies against malaria
Suppressive Effects on the Immune Response and Protective Immunity to a JEV DNA Vaccine by Co-administration of a GM-CSF-Expressing Plasmid in Mice
As a potential cytokine adjuvant of DNA vaccines, granulocyte-macrophage colony–stimulating factor (GM-CSF) has received considerable attention due to its essential role in the recruitment of antigen-presenting cells, differentiation and maturation of dendritic cells. However, in our recent study of a Japanese encephalitis virus (JEV) DNA vaccine, co-inoculation of a GM-CSF plasmid dramatically suppressed the specific IgG response and resulted in decreased protection against JEV challenge. It is known that GM-CSF has been used in clinic to treat neutropenia for repopulating myeloid cells, and as an adjuvant in vaccine studies; it has shown various effects on the immune response. Therefore, in this study, we characterized the suppressive effects on the immune response to a JEV DNA vaccine by the co-administration of the GM-CSF-expressing plasmid and clarified the underlying mechanisms of the suppression in mice. Our results demonstrated that co-immunization with GM-CSF caused a substantial dampening of the vaccine-induced antibody responses. The suppressive effect was dose- and timing-dependent and likely related to the immunogenicity of the antigen. The suppression was associated with the induction of immature dendritic cells and the expansion of regulatory T cells but not myeloid-derived suppressor cells. Collectively, our findings not only provide valuable information for the application of GM-CSF in clinic and using as a vaccine adjuvant but also offer further insight into the understanding of the complex roles of GM-CSF
- …