Geometrical Optics Formalism to Model Contrast in Dark-Field X-ray Microscopy

Dark-field X-ray microscopy is a new full-field imaging technique that nondestructively maps the structure and local strain inside deeply embedded crystalline elements in three dimensions. Placing an objective lens in the diffracted beam generates a magnified projection image of a local volume. We provide a general formalism based on geometrical optics for the diffraction imaging, valid for any crystallographic space group. This allows simulation of diffraction images based on micro-mechanical models. We present example simulations with the formalism, demonstrating how it may be used to design new experiments or interpret existing ones. In particular, we show how modifications to the experimental design may tailor the reciprocal-space resolution function to map specific components of the deformation gradient tensor. The formalism supports multi-length scale experiments, as it enables DFXM to be interfaced with 3DXRD. The formalism is demonstrated by comparison to experimental images of the strain field around a straight dislocation

Penn State University NSF GK-12 Project: Using Web-Based Education and Interaction with K-12 and College Freshman to Promote Science and Engineering

Penn State University has hosted an NSF-sponsored GK-12 Outreach project for the past five years, and has just begun the second phase of the project. The Penn State project utilizes the talents of many science and engineering graduate students as teachers, mentors and role models for the K-12 classrooms. The project focuses on developing skills of students in the areas of science, technology, engineering and mathematics through the use of Advanced Transportation Technologies. A new project component was devised and implemented-the interaction of K-12 students with college freshman via a website project. The college freshmen were asked to create a website describing a component of Clean Energy , which was to include an assessment tool to provide feedback on their website. When possible, the college freshmen were encouraged to use active learning and inquiry-based learning concepts. This was encouraged so that the college freshman had an opportunity to practice developing scientific inquiry as a skill through a presentation, and provided the K-12 classroom students a unique opportunity to learn through inquiry. The K-12 students were invited to participate in the research by reviewing and critiquing these websites through feedback via the website to the college freshman. The feedback could take many forms, including specific comments and critique along with a creative assessment tool that the college freshman decided to present with their subject materials. This paper will review the educational outcomes garnered by the students, and provide feedback and analysis from the K-12 and college freshman participants

Wavelets and graph C∗C^*-algebras

Here we give an overview on the connection between wavelet theory and representation theory for graph $C^{\ast}$-algebras, including the higher-rank graph $C^*$-algebras of A. Kumjian and D. Pask. Many authors have studied different aspects of this connection over the last 20 years, and we begin this paper with a survey of the known results. We then discuss several new ways to generalize these results and obtain wavelets associated to representations of higher-rank graphs. In \cite{FGKP}, we introduced the "cubical wavelets" associated to a higher-rank graph. Here, we generalize this construction to build wavelets of arbitrary shapes. We also present a different but related construction of wavelets associated to a higher-rank graph, which we anticipate will have applications to traffic analysis on networks. Finally, we generalize the spectral graph wavelets of \cite{hammond} to higher-rank graphs, giving a third family of wavelets associated to higher-rank graphs

Tumor microenvironment defines the invasive phenotype of AIP-mutation-positive pituitary tumors

The molecular mechanisms leading to aryl hydrocarbon receptor interacting protein (AIP) mutation-induced aggressive, young-onset growth hormone-secreting pituitary tumors are not fully understood. In this study, we have identified that AIP-mutation-positive tumors are infiltrated by a large number of macrophages compared to sporadic tumors. Tissue from pituitary-specific Aip-knockout (AipFlox/Flox;Hesx1Cre/+) mice recapitulated this phenotype. Our human pituitary tumor transcriptome data revealed the "epithelial-to-mesenchymal transition (EMT) pathway" as one of the most significantly altered pathways in AIPpos tumors. Our in vitro data suggest that bone marrow-derived macrophage-conditioned media induces more prominent EMT-like phenotype and enhanced migratory and invasive properties in Aip-knockdown somatomammotroph cells compared to non-targeting controls. We identified that tumor-derived cytokine CCL5 is upregulated in AIP-mutation-positive human adenomas. Aip-knockdown GH3 cell-conditioned media increases macrophage migration, which is inhibited by the CCL5/CCR5 antagonist maraviroc. Our results suggest that a crosstalk between the tumor and its microenvironment plays a key role in the invasive nature of AIP-mutation-positive tumors and the CCL5/CCR5 pathway is a novel potential therapeutic target

A atuação da Embrapa no semiárido.

O Semiárido brasileiro é uma região em evidência no contexto da produção agropecuária nacional, e a Empresa Brasileira de Pesquisa Agropecuária (Embrapa) tem atuação na região. Nesse bioma, diversas das atividades produtivas foram adaptadas às características do ambiente e os arranjos produtivos superaram os desafios iniciais. A Embrapa dispõe de soluções e tecnologias apropriadas ao contexto local, que intencionam ampliar o desenvolvimento regional por meio da mediação em convivência com a seca, limitações ambientais, deficiência logística e acesso a mercados. O mapeamento da atuação da Embrapa nos municípios da região é de interesse público, e a disponibilização dessa informação em visualizações dinâmicas facilita a compreensão da conjuntura. A solução encontrada para essa apresentação é uma página web de conteúdo dinâmico que apresenta, por meio de mapas interativos, as cadeias e os produtos contemplados pelas Unidades da Embrapa. O método utilizado para elaborar a solução apresenta um histórico bem-sucedido de aplicações e consiste em um fluxo de trabalho modularizado em cinco etapas consecutivas, que envolvem a modelagem de um banco de dados geográficos, a obtenção e o tratamento de dados geográficos e qualitativos e a posterior confecção dos painéis. A presente utilização desse método amplia a possibilidade de análise e validação dos dados trabalhados e também contribui para a compreensão e o desenvolvimento do próprio método

Volcanic air pollution and human health: recent advances and future directions

Volcanic air pollution from both explosive and effusive activity can affect large populations as far as thousands of kilometers away from the source, for days to decades or even centuries. Here, we summarize key advances and prospects in the assessment of health hazards, effects, risk, and management. Recent advances include standardized ash assessment methods to characterize the multiple physicochemical characteristics that might influence toxicity; the rise of community-based air quality monitoring networks using low-cost gas and particulate sensors; the development of forecasting methods for ground-level concentrations and associated public advisories; the development of risk and impact assessment methods to explore health consequences of future eruptions; and the development of evidence-based, locally specific measures for health protection. However, it remains problematic that the health effects of many major and sometimes long-duration eruptions near large populations have gone completely unmonitored. Similarly, effects of prolonged degassing on exposed populations have received very little attention relative to explosive eruptions. Furthermore, very few studies have longitudinally followed populations chronically exposed to volcanic emissions; thus, knowledge gaps remain about whether chronic exposures can trigger development of potentially fatal diseases. Instigating such studies will be facilitated by continued co-development of standardized protocols, supporting local study teams and procuring equipment, funding, and ethical permissions. Relationship building between visiting researchers and host country academic, observatory, and agency partners is vital and can, in turn, support the effective communication of health impacts of volcanic air pollution to populations, health practitioners, and emergency managers

Pretreatment 18F-FAZA PET Predicts Success of Hypoxia-Directed Radiochemotherapy Using Tirapazamine

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