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Capturing Your Environment Framework: Exploring Microclimates Using Infrared Thermometers and Kestrel Weather Stations
No full textThe Capturing Your Environment
(CYE) Framework uses DOTS in the 5E
Instructional Model to address specific
learning goals inspired by the Essential
Principles of Climate Literacy and the
Next Generation Science Standards
(NGSS), as outlined on the next page.
The CYE Framework sets a foundation
for learners to gain STEM skills and
experiences to use as future scientists.Background
Digital Observation
Technology
Skills (DOTS)
Using technology has the potential
to deepen learning for all ages. As
skills increase with technology use,
learners can explore their environment
in a new way. Technology can also give
learners access to information about
their environment. Learners can use
digital tools to gather observation data
beyond their five senses.
Introducing DOTS in learning settings
is an effective way to improve learning
outcomes. DOTS uses technology that
allows learners to observe the natural
world. DOTS uses a toolkit that includes
digital mobile technology devices. The
tools in the kit can range from digital
microscopes and weather meters to
other tools that support data collection.
The DOTS tools are chosen based on
utility, cost, ease of use, and the ability
to collect clear and useful data. Mobile
technology, such as tablets or cell
phones, may be a distraction when used
outdoors. However, using technology
that prioritizes a task-oriented
experience with a distinct function
can limit distractions. For example, the
Infrared Thermometer in the toolkit only
has one function, to measure surface
temperature.
The Capturing Your Environment
(CYE) Framework uses DOTS in the 5E
Instructional Model to address specific
learning goals inspired by the Essential
Principles of Climate Literacy and the
Next Generation Science Standards
(NGSS), as outlined on the next page.
The CYE Framework sets a foundation
for learners to gain STEM skills and
experiences to use as future scientists
Fluency Development Through Timed Repeated Reading
No full textThis action research study explored the impact of repeated reading on fluency. Fifteen third
grade students participated in three one-minute timed repeated readings per week in order to
investigate the impact of such practice readings on WCPM (words correct per minute). The
results were varied; nine students achieved and even surpassed year-end benchmarks while other
students experienced a decrease in their WCPM over the nine-week intervention. Factors such as
familial adjustments, motivation, attendance and diverse reading levels are speculated to be root
causes of complications exhibited in reaching benchmark numbers in WCPM. The research
findings also indicate a need for differentiated learning strategies, including comprehension
instruction, to be embedded into the interventions that accompany fluency practices
Climbing Without a Ladder: The Lived Experience of Military Spouses and Their Non-linear Paths to Self-Actualization, Identity, and Growth
No full textFull Text DissertationIn this qualitative narrative study, I examined lived experiences of a purposive sample of 11 Active duty military spouses. I conducted in-depth interviews in which I sought to learn about their military lifestyles and their perceptions of life satisfaction, self-actualization, perceived identity, individual agency, and sense of belonging. Participants reported personal growth, fulfilment and identity reconstruction concurrent with the constraints and inconsistencies of military life, that included frequent relocations, career disruptions, and constrained autonomy. Participants reported continual, nonlinear processes of redefining their purposes, identity, and fulfilment. I conclude that policies and support systems should be inclusive and responsive, reflecting the lived realities of military spouses and recognizing the potential for growth amid constraint
OPTIMIZATION OF A GEN3 CONCENTRATING SOLAR POWER SYSTEM WITH A SILICON CARBIDE PRIMARY HEAT EXCHANGER
No full textThis study evaluates the technical and economic impact of a topology-optimized silicon carbide (SiC) primary heat exchanger on the energy-specific cost and optimized design of Gen3 concentrated solar power (CSP) plants. Gen3 CSP systems aim to replace nitrate salt with solid particles such as silica sand or manufactured ceramics like Carbo HSP 40/70. Particles can operate at temperatures exceeding 1000 °C without material degradation, enabling smaller heat exchangers, reduced parasitics, and higher power-cycle efficiency. However, transferring heat from particles to a working fluid is challenging without direct mixing, which is precluded by extreme pressure differentials between the pressurized working fluid and the particles.
Primary heat exchangers in Gen3 CSP systems must tolerate temperatures above 700
°C while resisting continuous abrasive wear. SiC satisfies these requirements and enables operation at elevated temperatures, but higher temperatures do not monotonically reduce energy-specific cost. While efficiency improves, higher temperatures also reduce falling-particle receiver efficiency and increase the cost of turbomachinery, lifts, storage, and piping. These tradeoffs are explored through a detailed techno-economic optimization of a system-level Gen3 CSP model.
The model is implemented in a modified version of the National Renewable Energy Laboratory’s System Advisor Model and includes a supercritical CO2 closed Brayton cycle, solar field, receiver, particle lift, thermal energy storage, and primary heat exchanger. Computationally efficient submodels are used for each component in the system. Op-timizations adjust recompression ratio, split fraction, and recuperator conductance to minimize energy-specific cost, while parameters such as turbine inlet temperature are varied parametrically.
Results indicate that a topology-optimized SiC primary heat exchanger can reduce energy-specific cost by up to 40% over a baseline. The dominant driver of reduced energy-specific cost is the lower particle flow rate enabled by higher operating temperatures, which increases energy density and reduces parasitic losses.U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under the Solar Energy Technologies Office Award Number DE-EE0010319
INFORMAL WORK AND OCCUPATIONAL STRUCTURE BLURRING
No full textHow does the growth of informal work reshape the long-standing organization of labor markets and social hierarchies? Using Hughes's distinction between the functional and moral aspects of occupational differentiation, this article explores whether the rise of "multiple jobholding"—where workers engage in multiple occupations simultaneously—undermines the occupational structure that separates jobs both hierarchically and horizontally. The study combines data from six waves of the Survey of Informal Work Participation (2015-2020) with occupational data from the American Community Survey and O*NET to illustrate how 95 different occupations interact with 15 types of informal work. It distinguishes between two levels of involvement: incidence (whether occupations engage in specific gigs) and intensity (the amount of time dedicated to such work). While initial participation seems generally accessible across various occupations, patterns of ongoing engagement highlight that hierarchical and functional distinctions remain influential. Furthermore, dyadic additive–multiplicative effects models show that the clarity of these distinctions varies systematically along the occupational hierarchy. Status hierarchies become most rigid at the top. Conversely, functional differentiations follow a curvilinear pattern—being most blurred among middle-status occupations but remaining clearer at both ends of the hierarchy. These results imply that rather than flattening occupational differences, the gig economy might reinforce existing stratification through new mechanisms. The analysis adds to theories of intragenerational mobility by showing that the clarity of occupational distinctions operates as a structural feature, independently of individual moves across jobs
FIRST IONIZATION POTENTIALS OF CR, MO, AND W CALCULATED WITH SHCI
No full textThe design and performance of future fusion power plants will depend on accurate atomic data for plasma-facing material and plasma impurity species. A leading candidate for the plasma-facing material is tungsten due to its high melting point, however, the energy levels and wavefunc-tions of high-Z atoms with many electrons (e.g. 30 or more), including tungsten, are difficult to calculate with high accuracy. Gaps and large un-certainties in atomic data for tungsten introduce design and performance uncertainties for a fusion power plant. Specifically, improved atomic data for ionization potential, excited state energies, and collisional excitation rates are needed for the low charge states of atomic tungsten. We aim to address these shortcomings by using the semistochastic heat-bath config-uration interaction (SHCI) method, which nearly exactly calculates the energies that can be determined at higher cost with the full configuration interaction. Adding well-motivated approximations to SHCI, including orbital optimization and effective core potentials, we demonstrate good agreement between our calculated first ionization potentials and the best available experimental values for chromium, molybdenum, and tungsten. The efficiency and accuracy achieved in calculating these ionization poten-tials demonstrates that our SHCI workflow can yield improved electron structure data for ions with many electrons, suggesting that the method could also be useful for collisional processes, such as state-selective charge exchange reactions and electron impact ionization
CFD Modeling of Superimposed Streaming Phenomena in Various Pulse Tube Geometries
No full textIn a pulse tube cryocooler, the pulse tube acts as an adiabatic “gas piston”, whose function is to transport work from a cryogenic region to a warmer region, where it can be rejected as heat. Mass streaming effects, which refer to secondary flows induced by interactions between first order oscillating quantities, can introduce heat leaks that reduce the efficiency of the pulse tube. Of the three forms of streaming relevant to pulse tubes, Rayleigh streaming (or acoustic streaming), Jet streaming, and Gedeon streaming, each type has been studied only individually; in a real pulse tube, multiple forms of streaming are likely present. Previous authors examining streaming have highlighted deviation between the performance predicted by current analytical models and real hardware, which may be caused by some nonlinearity caused by streaming. Given the similarities between the mechanisms for each streaming type, coupling may present, such that the net effect of all forms of streaming is amplified or attenuated.
In this work, standard analytical and empirical models are used to predict the location of influence, the magnitude, and the system-level performance impact of individual Rayleigh streaming, Jet streaming, and Gedeon streaming by a liner superposition of their respective streaming velocities. Several pulse tube geometries, aspect ratios, and power levels, yielding concurrent streaming of varying types and intensities, are then simulated numerically by a computational fluid dynamics (CFD) model in ANSYS Fluent. These models confirm that, while not strictly true, adjacent positive Rayleigh, negative Rayleigh, and Jet streaming cells can be approximated as a linear superposition of their streaming velocities at moderate pressure amplitudes. Distinct inner and outer streaming characteristics are resolved for the first time in a CFD model of a traveling wave thermoacoustic device, and inner streaming is identified as a source of nonlinearity through thermal coupling between the streaming structure and the tube walls that be either advantageous or disadvantageous depending on the sign of the rotation of each cell. The importance of a zero-streaming “buffer region” within the pulse tube, which can reduce heat leak, is highlighted. Limitations of current methods for predicting streaming velocities and cell locations are specified. Lastly, this study identifies that a converging/diverging pulse tube geometry minimizes streaming losses for most inertance type pulse tubes, and that this choice of geometry should simultaneously improve performance over a straight pulse tube and enable access to a wider range of acoustic impedances without streaming induced penalty
Surgery that targeted appearance prior to the Twentieth century
No full textSurgery for appearance has a long history. This paper seeks to collect the evidence of such surgery prior to the twentieth century.This paper collects reports of surgery for appearance prior to the twentieth century
MANAGING WILD PARSNIP (PASTINACA SATIVA) IN TALLGRASS PRAIRIES
No full textPollinators thrive and provide key extensive ecosystem services when provided with sufficient habitat. Tallgrass prairies can provide sufficient habitat as they are often dominated by flowering plants throughout the year that provide resources to the development of pollinators. Wild parsnip (Pastinaca sativa L.) is an invasive monocarpic species that is common throughout the midwestern United States. P. sativa invades and displaces native forbs within tallgrass prairies which reduces biodiversity of plants and pollinators. While control of P. sativa can be easily accomplished with a range of approaches, the presence of native forbs limits methods that can control P. sativa to individual plant treatments as this limits injury to desirable forbs. Florpyrauxifen-benzyl is a new herbicide that many native forbs may be tolerant to, allowing it to be broadcasted, but its effectiveness on P. sativa is not known. Another approach that could limit native forb injury but control P. sativa could be to apply glyphosate to resprouting plants after a spring burn prior to native forb emergence. Studies evaluated the effectiveness of broadcast spraying florpyrauxifen-benzyl and spot treating glyphosate after spring burn as management technique in controlling P. sativa in infested tallgrass prairies. Studies also evaluated if techniques could improve native forb populations. Three experiments were conducted over three years to evaluate if 0.9-29.4 g ai ha-1 of florpyrauxifen-benzyl broadcast controls P. sativa when applied in spring. One separate experiment was done to assess the benefit in an invaded tallgrass prairie, application of florpyrauxifen-benzyl (14.7 g ai ha-1) alone and or florpyrauxifen-benzyl (11 g ai ha-1) mixed with imazapic (35 g ae ha-1) were compared to a non-treated control. One experiment was conducted in order to evaluate the effectiveness of applying 2% glyphosate after a spring burn. Results found both approaches were successful in reducing P. sativa populations, with florpyrauxifen-benzyl removing more (90-100% reduction) than burn + glyphosate (45-52% density reduction) 2 months after treatment. While, total native forb cover decreased as a result of both approaches, the impact was not severe one year after application (< 25% cover reduction). Given that native forb response was species specific, future research should evaluate the range of tolerances that different species have to inform management approaches of P. sativa in tallgrass prairie
Multi-Levels of Influence on Bullying Behavior among High School Students in Saudi Arabia
No full textBackground: Exposure to bullying behavior can significantly impact the physiological andpsychological well-being of affected adolescents. Despite this, there is a lack of literature in Saudi Arabia addresses the factors influencing bullying behavior among high school students. This study aims to fill some of these gaps by employing modeling analysis to identify the predictive factors that influence the dynamics of bullying behavior. Purpose: To understand the multi-level influences on bullying behavior among high school students in Saudi Arabia. Methods: The study utilized a quantitative, cross-sectional descriptive correlation design and a convenience sampling approach to recruit participants. The proposed population was male and female from grades 10, 11, and 12, aged 16 to 20. Participants completed a self-report survey measuring their (a) demographic background information, (b) bullying behaviors (BCS-A), (c) inventory of Parent and Peer Attachment (IPPA), (d) the School Environment Support, and (f) Difficulties in Emotional Regulation Scale (DERS). Descriptive statistics, frequencies, and multiple linear regression were used to analyze the data. Results: The study identified parental attachment, the school environment, and difficulties in emotional regulation as significant predictive factors affecting student outcomes. Additionally, mediation analysis indicated that difficulties in emotional regulation act as both a partial and a full mediator for bullying behavior. Conclusions: The findings of this study underscore the importance of implementing targeted protective and preventive measures to address bullying within the context of parent-school relationships. There is a clear need for specific strategies to tackle bullying issues in schools. These results have significant implications for stakeholders involved in bullying prevention, including school nurses, mental health professionals, and school psychologists.2027-05-2