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Effect of Geopolymerization on the Curing Progression and Compressive Properties of Wood Composite Material
No full textWood composites can serve as sustainable and cost-effective alternatives to currently used large-scale additive manufacturing materials. This study explored geopolymerization, the formation of three-dimensional aluminosilicate bonds, as a binder in wood composites. The mechanical properties and water resistance of various wood-sodium silicate(ss) composites, including 0-25% metakaolin by total dry mass, were assessed through compression and soak tests. 20% metakaolin content provided the best resistance to water absorption with the smallest volume expansion. Compression testing showed that plain wood-ss composites possessed the highest strength and stiffness; however, in formulations where geopolymerization occurred, an increase in metakaolin improved compressive properties. A 50/50 wood-ss mixture was subject to compression testing at varying time intervals to assess its curing progression. Using an oven-cured sample as a control, the composite showed stiffness reaching 93% of its maximum near 250 hours and 97% around 350 hours, while stress reached 96% at 250 hours and 98% near 350 hours. Results obtained from this study suggest that metakaolin improves water resistance but may reduce physical performance when used in a 1:1 wood-to-binder ratio. These findings help guide binder formulations toward more practical and sustainable printed composites
SrTiO\u3csub\u3e3\u3c/sub\u3e Single Crystalline Membranes Studied by Ultraviolet Raman Spectroscopy
No full textFerroelectrics are materials possessing a spontaneous and switchable electrical polarization, which is exploited for various electronic devices such as non-volatile memories or tunable microwave devices. Strontium titanate, SrTiO3 , is a material which remains in a non-ferroelectric state down to liquid helium temperatures. However, a slight perturbation, such as strain, oxygen isotope substitution, or doping can lead to the appearance of ferroelectric polarization. We have studied free-standing single-crystalline SrTiO3 membranes grown by hybrid molecular beam epitaxy using selectively dissolved sacrificial layers by variable temperature Raman spectroscopy with ultraviolet excitation (325 nm). Bulk SrTiO3 has a cubic perovskite structure with all phonon modes being symmetrically forbidden in the first order Raman spectra. The membranes show behavior characteristic of ferroelectrics at low temperatures. Strong first order optical phonon modes have been observed, including the lowest-frequency modes, which exhibit characteristic softening with increasing temperature. From the temperature evolution of Raman intensities for the hard modes of the ferroelectric phase transition temperature, Tc is determined to be in the range 250–300 K, consistent with the temperature dependence of the soft mode frequencies. A possible explanation for the observed behavior can be a non-uniform strain in the membranes
Cervical Cancer and Its Preventive Behavior Among Tamang Women Residing in Nuwakot, Nepal
No full textBackground: Persistent Human Papillomavirus infection of the cervix causes cervical cancer. Cervical cancer is the fourth most common cancer among women worldwide and it is the leading cause of cancer-related death among Nepalese women. It is preventable through primary prevention (vaccination) and secondary prevention (screening). Individuals’ vaccination and prevention behaviors are thought to be determined, in part, by knowledge and attitude regarding cervical cancer and prevention behavior. Therefore, the objective of this study was to assess cervical cancer-related preventive behaviors and associated barriers and facilitators among Nepali Tamang women residing in Nuwakot, Nepal.
Methods: Using a cross-sectional design and convenience sample, data were collected by visiting the homes of Tamang women. In the Kakani, Likhu, and Shivapuri municipalities, we interviewed 251 women who spoke and understood Nepali and could provide verbal consent. Descriptive statistics were used to describe participants and regression models were created to assess relationships between participant characteristics and determinants of cervical cancer prevention behavior.
Results: Among the 251 participants, data from 250 was utilized. On average, participants were 37 years old, married at 17, and had their first child at almost 19. Most participants knew about cervical cancer, whereas less than half knew about the cervix and uterus. Generally, participants had a low level of cervical cancer knowledge and a positive attitude toward prevention behaviors. Only 18% of participants had ever been screened for cervical cancer, and of those, only 66.7% had been screened once in the last five years. Participants who knew what cervical cancer is or knew at least one risk factor) had higher odds of getting cervical cancer screening. The most common barriers to cervical cancer screening were “no symptoms, “nothing had happened,” “do not know about prevention,” and “no health care services.”
Discussion: Tamang women of Nuwakot, Nepal had low awareness about cervical cancer and inadequate cervical cancer screening practices. However, women tended toward a positive attitude toward screening and vaccination. Therefore, there is a need for awareness programs addressing cervical cancer, and its primary and secondary prevention methods
Empirical Models for the Prediction of Lattice Constants in Perovskite Materials
No full textPerovskites are a class of materials famous for their many functional properties and are envisioned as a material that will pave the way for scientific advancement in the fields of renewable energy, high tech sensors, lasers, catalysis, computer chips, and many others. This wide variety of applications is not the result of a single fantastic property of perovskite materials but rather stems from the perovskite structure’s ability to display a host of functional properties. One area where there is room for significant improvement is in the rate of perovskite discovery. The high stability of the perovskite structure is responsible for the many properties that it possesses, but it also greatly increases the compositional space that these properties can exist within which can make finding the best composition for a specific application both an exciting challenge and opportunity for further innovation. It is for this reason that a comprehensive understanding of the structure-processing-property relationship within perovskite materials could be a transformative breakthrough for a litany of high tech fields.
Chapter One provides an overview of the key properties held by perovskites, the atomic structures that produce those properties, the processing techniques that are used to create those structures, as well as some promising methods for accelerating the discovery of new perovskite materials. Although other methods are briefly discussed, the primary focus of this work is on the development of empirical modeling tools that can predict the properties of a perovskite composition using widely known or easy to measure inputs. Historically, the research on new perovskite compositions has heavily focused on optimizing a few compositional ranges where properties are well explored and generally understood while completely new compositions are avoided because the risks of spending limited resources on a “blue skies” research area are generally too high. Predictive tools such as the empirical modeling tools developed in this work have the potential to lower the barriers associated with researching unexplored compositions by providing clues as to which ones are likely to hold the desired properties.
Chapter Two is focused on the development of an empirical model that accounts for the effects of 1:2 B-site ordering in perovskites and can both predict the pseudocubic lattice constant of these materials and assist in determining the degree of ordering present in experimental samples. This model uses only the Shannon ionic radii values as inputs, which in turn means that this model can be used knowing only the charge and the coordination of the ions in any perovskite composition. Additionally, to supplement the limited data for this ordering type, three compositions in the BSMT system were synthesized using conventional solid-state mixed-oxide synthesis techniques.
Chapter Three refines previously developed models by correcting several errors that have persisted through the development of several models and then compares the efficacy of these models on a data set in which several minor errors have been corrected. Like most scientific progress, the development of empirical modeling techniques has been gradual and has been built upon the work that came before it. In this case, several minor errors and inconsistencies in the data set used in one of the founding empirical models for perovskites have been propagated through many models that have built upon that work. The correction of these errors has not only improved the predictive accuracy of existing models but also created a platform for the comparison and analysis of these models
Impact of a Light Volleyball Intervention Among Older Chinese Adult Women
Get PDFModified sports offer a strategic approach to promoting health in older adults. Light volleyball, which uses a larger, lighter ball than traditional volleyball, is more accessible for this population. This study investigated the effects of a 16-week light volleyball program on the functional fitness of older adults in Hong Kong. A total of 275 participants aged 60 years or older were recruited and randomly assigned to three groups: a light volleyball intervention group, a Tai Chi group, and a control group. Functional fitness was assessed at the pretest, posttest, and 6-month follow-up. Results revealed that the light volleyball group exhibited more significant improvements in lower and upper limb strength, agility, dynamic balance, and aerobic endurance than did the Tai Chi and control groups. This study highlights the effectiveness of light volleyball as a newly emerging, group-based sport physical activity for promoting healthy aging in older adult women. The use of light volleyball in future health promotion initiatives is highly recommended
Birding for a Better Tomorrow (Flyer)
Get PDFThe natural world is in desperate need of some healing—and so are we. Can attention to birds, as one of the most accessible gateways to nature, offer a way forward for a planet in trouble while also bridging some of the chasms between us human beings? Practically born with a pair of binoculars in his hands, Cooper is the vice president of New York City Bird Alliance. He advocates for greater, safer access to green spaces for all, with a focus on outreach to youth in underserved communities. A longtime activist on issues of racial justice and LGBTQ equality, Christian combined his passions in the BLM graphic short story It’s a Bird” from DC Comics, and he continues to seek synergy at the intersections of storytelling, progressivism, and environmentalism
Program Evaluation: Family Centered Rounding to Support Communication in Pediatric Care
Get PDFBackground: Family centered rounding (FCR) is a pediatric evidence-based practice intended to bring healthcare teams, patients, and families together at the bedside in a collaborative approach to care planning. FCR emphasizes communication and shared decision-making between healthcare teams and families, leading to improved patient outcomes. Despite well-documented benefits of FCR, challenges such as inconsistent nursing participation, variability in practices, and workflow disruptions hinder implementation and sustainability of FCR.
Aim: This program evaluation was designed and conducted at an urban pediatric hospital to assess the processes, perceptions, and impact of FCR. The overall quality of FCR and the strengths and barriers to FCR practices were also assessed.
Methods: Guided by the Center for Disease Control and Prevention’s Program Evaluation Framework, stakeholders were identified, followed by structured interviews and FCR observations. An interview and observation template was created based on critical rounding elements described in current literature. Evaluation outcomes included the identification and thematization of perceived barriers and strategies to enhance FCR.
Outcomes: 81 rounding interactions were observed with 12 hospitalists. During the observation period, FCR occurred infrequently, with only 18% of patients. 12 hospitalists and 43 registered nurses (RNs) participated in interviews. Themes from hospitalists\u27 perspectives included inconsistent FCR protocols based on patient acuity and RN availability. Themes from RNs included concerns about receiving adequate notice to coordinate for and participate in FCR. Both hospitalists and RNs identified benefits to FCR, which included improved communication, patient/family participation, and teamwork. Recommendations for improving FCR included clinician education regarding elements of FCR, addressing workflow issues such as RN coverage, and improving interdisciplinary attendance/participation in FCR.
Impact: FCR enhances communication and strengthens collaboration between healthcare teams and families, thus improving patient outcomes, making it an important part of patient-and family-centered care.
Summary: Family centered rounding (FCR) is a key practice in pediatric care that fosters collaboration, shared decision-making, and improved outcomes. Despite its benefits, challenges such as inconsistent nursing participation, workflow disruptions, and practice variability hinder effectiveness. A program evaluation at an urban pediatric hospital assessed FCR, revealing barriers and facilitators. Findings highlight the need for standardized protocols, improved interdisciplinary participation, and operational adjustments to enhance FCR
Studying Parkinson\u27s Disease-Like Molecular Changes in Dopaminergic Neurons Exposed to Simulated Microgravity
No full textSpace flight (SF) exposes astronauts to various stressors, including microgravity, cosmic radiation, hypercapnia, ischemia, isolation, and confinement, the long-term effects of which have been linked to the onset of neurodegenerative disorders such as Parkinson’s disease (PD). This ground-based study investigates the effects of one such SF stressor—simulated microgravity (SMG)—on dopaminergic neurons, specifically focusing on its potential to induce PD-related neurodegeneration. We used a custom-built clinostat to simulate microgravity in neuronal cultures and characterized its operation by measuring the G-forces experienced by the neurons using an accelerometer. To evaluate the effects of SMG on cellular stress and degeneration, we conducted mitochondrial health analysis, image analysis, and neuronal morphometric assessments on neurons exposed to SMG. Furthermore, we employed qPCR and Western blot techniques to examine the time-dependent impact of SMG on PD-like molecular signatures in these neurons, including alterations in key PD-related markers. Our findings suggest that exposure to SMG induces molecular and morphological changes consistent with PD-like pathology in dopaminergic neurons. Given the planned manned missions to the Moon and Mars, understanding the impact of prolonged simulated microgravity (SMG) on neurodegenerative diseases is crucial. Continued research is essential to identify the risks of such neurodegeneration and to develop effective countermeasures that can mitigate these effects during long-duration space travel
Geothermal at a Glance
No full textGeothermal energy receives mixed public perception, with both a strong interest in its potential and concern over risks such as water pollution and induced seismicity. Monitoring efforts are viewed as an important topic in addressing these challenges. Politically, geothermal energy faces barriers due to its long development timelines, which may not align with short-term political agendas, and skepticism around land use and equitable distribution of benefits. Technologically, geothermal offers several advantages, including round-the-clock operation, load-following capabilities, and sustainable fuel from the Earth’s core. However, it also presents challenges such as high water usage, air pollution, and the release of toxic substances. Enhanced Geothermal Systems (EGS) have been studied across decades as a promising solution to expand geothermal viability to less favorable geological regions. Advances in drilling technologies—such as multistage stimulation, horizontal drilling, and compact diamond bits—have improved efficiency and reduced costs. While many EGS projects remain in testing phases, the U.S. has led in large-scale application, aiming for a 100,000 MWe base capacity by 2050. Recent projections suggest EGS could achieve market-competitive pricing by 2027. Continued innovation and integration of geothermal energy, particularly in the western U.S., position it as a valuable asset to the national energy portfolio
The Lower Snake River Dams
No full textThere have been many debates regarding removing or keeping the four dams. Each side has pros and cons, and this poster will break them down into common groups: economic impact, social impact, tribal impact, and environmental impact. Multiple studies have been conducted on these topics, and viewers of the poster will be able to digest all of them in a poster-like manner. The studies are done by universities, private organizations like the BLM, or state agencies. Each study was reviewed for biases in the paper and tested for credibility. This poster will not answer removing or keeping the dams but leaving the viewers to decide for themselves what they value more. The goal is to expose both sides of the prompt and educate the impacts for each side