2,173 research outputs found
Decoupled Solar Thermal Chemical Electrolysis of Water to Produce Hydrogen
Solar thermal chemical research at Valparaiso University focuses on using concentrated solar energy to produce hydrogen, which can be used to generate electricity in fuel cells. A two-step solar electrolytic process has been proposed for chemical systems such as Fe2O3/Fe3O4, Co3O4/CoO, and Mn2O3/MnO. This new process produces hydrogen using ideally 63-82% less electricity than the traditional electrolytic process. Theoretical solar-to-electrical efficiencies are approximately 19-40%, a range comparable to similar solar thermal chemical processes. Preliminary experimental work with the Fe2O3/Fe3O4 system has validated the chemical possibility of each step of the process. Future work seeks to determine if the proposed processes are all chemically possible, optimize their operation on a small scale and explore their viability on an industrial scale
The effects of childhood poverty on adult health outcomes
This paper is a review of the literature regarding the effects of childhood pove1ty on adult health, employment, and socioeconomic status. Children who grow up in lower socioeconomic homes often have fewer advantages available to them including level and quality of education, quality health care, and family support. Growing up with these disadvantages impacts in adult health outcomes, adult employment and earnings, and adult socioeconomic status. There arc many direct and indirect associations between childhood poverty and adult outcomes
The Relationship Between Core Knowledge Sequence Curriculum and Smarter Balance Assessment English Language Arts Scores
The purpose of this study was to examine student achievement as measured by the English language arts (ELA) Smarter Balance Assessment (SBAC) between students who were taught the Core Knowledge Sequence curriculum and students taught the Houghton Mifflin Harcourt’s Journeys curriculum. The 11,493 participants were third through sixth grade students in the 2014-2015, 2015-2016, and 2016-2017 school years. The study used a multiple regression model to examine the extent to which the students’ gender, ethnicity, socioeconomic status (SES), disability status, English language learner (ELL) status, and curriculum predicted SBAC ELA scores. The findings of this study suggest that curriculum did not predict SBAC ELA scores. The multiple regression model indicated that demographic variables offer more predictive information on SBAC ELA scores
Tumors Interrupt IRF8-Mediated Dendritic Cell Development to Overcome Immune Surveillance
Tumors employ multiple mechanisms to evade immune surveillance. One mechanism is tumor-induced myelopoiesis, which expands immune suppressive granulocytes and monocytes to create a protective tumor niche shielding even antigenic tumors. As myeloid cells and immune-stimulatory conventional dendritic cells (cDCs) are derived from the same progenitors, it is logical that tumor-induced myelopoiesis might also impact cDC development. The cDC subset cDC1 is marked by CD141 in humans and CD103 or CD8α in mice. cDC1s act by cross presenting antigen and activating CD8+ T cells. Given these functions, CD103+ cDC1s can support anti-tumor CD8+ T cell responses. However, CD103+ cDC1 numbers are limited within the tumor microenvironment. To understand how CD103+ cDC1s are restricted in the tumor, we investigated their development in the bone marrow (BM). We found that the presence of localized primary tumors resulted in systemic decreases in CD141+ cDC1s in breast and pancreatic cancer patients and animal models. Mechanistically, tumor cell-produced granulocyte stimulating factor (GCSF) mediates the downregulation of the transcription factor interferon regulatory factor 8 (IRF8) in BM progenitors, leading to reduced cellular potential for cDC1 development. Tumor-induced reductions in cDC1-development suppressed the ability of the host to mount anti-tumor CD8+ T cell responses and control tumor growth. Further, BM and systemic decreases in CD141+ cDC1s and their progenitors correlate with patient outcome. Neutralizing GCSF restored cDC1 differentiation and recovered responsiveness to cDC-mediated immunotherapy. These data suggest a new mechanism of immune-escape whereby tumors downregulate cDC1 differentiation from BM progenitors to impair anti-tumor immunity
Pressure Drop in Condensing Superheated Zone
Traditionally, condensation is characterized by three zones: desuperheating, condensation and subcooling. It was shown that condensation starts even in the presence of superheated vapor, when the wall temperature reaches saturation. Heat transfer effects of that process were described earlier but not pressure drop that was found to indicate the presence of condensate, the same as shown by heat transfer results. Pressure drop in condensers has traditionally been modeled separately for single-phase and two-phase regions. When plotted as a function of enthalpy, the correlations show a discontinuity between the single-phase and two-phase zones because the models typically assume thermodynamic equilibrium during condensation. This assumption indicates that the first drop of condensate would form when the bulk refrigerant enthalpy reached the saturated vapor enthalpy. The zone beginning when the wall temperature reaches the saturation temperature and ending when the bulk enthalpy reaches saturated vapor is classified as the condensing superheated zone. In this condensing superheated zone, the interaction between the condensate film and vapor increases the pressure drop compared to vapor alone. This paper presents experimental results for pressure drop in that zone of the condenser for R32, R134a and R1234ze(E). The pressure drop was found to be higher than predicted by single-phase correlations such as Colburn (1933)
Self-directed disability support: building people’s capacity through peer support and action research
How are people with disability experiencing and managing the transition towards self directed support and preparing for the NDIS? In this project, small groups of people with disability around Australia met over 6 months to talk about their disability support. The peer support groups enabled action research about how they are deciding the practical details about support, such as how, when and by whom it is provided
Structure strategy interventions: Increasing reading comprehension of expository text
In this review of the literature we examine empirical studies designed to teach the structure strategy to increase reading comprehension of expository texts. First, we review the research that has served as a foundation for many of the studies examining the effects of text structure instruction. Text structures generally can be grouped into six categories: comparison, problem-and solution, causation, sequence, collection, and description. Next, we provide a historical look at research of structure strategyinterventions. Strategy interventions employ modeling, practice, and feedback to teach students how to use text structure strategically and eventually automatically. Finally, we review recent text structure interventions for elementary school students. We present similarities and differences among these studies and applications for instruction. Our review of intervention research suggests that direct instruction, modeling, scaffolding, elaborated feedback, and adaptation of instruction to student performance are keys in teaching students to strategically use knowledge about text structure
Designing a Calorimeter to Calibrate an Optical Radiative Flux Measurement System to Find the Power Entering a Solar Reactor
A solar furnace has been constructed at Valparaiso University to test the performance of various solar chemical reactors. A primary performance index of a solar chemical reactor is the efficiency, or the fraction of the energy that enters the reactor that is utilized in the chemical reaction. To calculate this efficiency, we must first know how much solar power is entering the reactor. An optical radiative flux measurement system has been developed that gives the solar flux distribution over the aperture of the reactor, but must be calibrated to provide the actual power level. Therefore, a calorimeter was designed and built to perform this calibration. The calorimeter is designed so that the solar power entering the aperture is transferred to water flowing through the tubes that make up the cavity. Then, by measuring the flow rate of the water and the temperature of the water at the inlet and outlet, the energy entering the calorimeter can be calculated using the first law of thermodynamics. The uncertainty in the calculated power level has also been established through a thermal loss and measurement uncertainty analysis
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