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Benchmarking the Global Warming Potential of Asphalt Pavements in West Virginia
Get PDFWith the rising focus on sustainable infrastructure, interest in environmentally friendly paving practices has grown significantly. This thesis investigates the environmental impacts of asphalt mixtures in West Virginia from a sustainable asphalt mix design perspective, with a particular emphasis on the utilization of Life Cycle Assessment (LCA). The research aligns with the U.S. Federal Highway Administration (FHWA) Climate Challenge, which aims to encourage state Departments of Transportation (DOTs) to implement low-carbon materials and consider the ecological effects of their paving activities. This study establishes the initial benchmark values for greenhouse gas emissions associated with asphalt pavements in West Virginia. The study collected various asphalt mix designs and materials from producers throughout West Virginia and analyzed them using LCA methodologies. Reclaimed Asphalt Pavement (RAP) has been demonstrated to be a viable method for reducing the carbon footprint of asphalt mixes. Increasing the RAP content in asphalt mixes from zero to 25 percent led to an average 21 percent reduction in carbon footprint. The evaluation employed the FHWA LCA Pave tool and included sensitivity analyses to determine the environmental effects of varying mix compositions. In addition, performance testing was conducted to determine change in the material\u27s sensitivity to rutting and cracking when the RAP percentage was increased. As was the case with prior research, the findings demonstrated that increased levels of RAP enhance rutting resistance and potentially reduce cracking resistance. Recommendations include using Balanced Mix Design (BMD) methodologies and the investigation of rejuvenators to mitigate cracking issues. The study advocates the use of RAP in a low-carbon transportation materials strategy and highlights the need for continued investigations to achieve a balance between environmental benefits and pavement durability
A Multimodal Physical Fatigue Assessment Method Using a Biomarker and Accelerometer-Embedded Wearable Wristband
No full textPhysically demanding tasks pose significant challenges to worker health, safety, and productivity across various industrial sectors in the United States. The construction industry is particularly affected due to the labor-intensive nature of its tasks and harsh environmental conditions. The industry suffers from unsatisfactory occupational health and safety records, with physical fatigue being a major contributor. Physical fatigue not only affects individual well-being and workplace safety but also influences productivity and the United States’ economy. Given the high incidence of injuries and accidents in the construction industry, assessing physical fatigue has become critical for improving worker safety and productivity. To address this need, this thesis consists of two specific aims: (1) to conduct a comprehensive analysis of emerging technologies that reduce ergonomic hazards and examine current fatigue assessment methods used in the construction industry and (2) to investigate a multimodal physical fatigue assessment method utilizing a wearable sensor embedded with biomarkers and accelerometers. A laboratory-based experiment was conducted with twenty-two participants who performed heavy material handling tasks involving 33.07 lbs. weight. Both physiological data, such as heart rate and skin temperature, and kinematic data, namely jerk—a time derivative of acceleration—were collected along with subjective fatigue assessment scores using Borg’s RPE (6-20) scale. The incorporation of jerk addresses the limitations of physiological data, particularly in tasks that require precise motor control, such as assembling delicate parts and laparoscopic surgery. In such tasks, physiological variables may remain unchanged compared to resting conditions, making it difficult to assess fatigue. However, the inclusion of jerk as a variable provides valuable insights into motor control and motion smoothness, enabling a more accurate and reliable assessment of physical fatigue. The results indicate that integration of these datasets can objectively and accurately assess physical fatigue, demonstrating the significant potential for multimodal method across various industrial settings. This study contributes to the body of knowledge in the field of occupational safety and health by demonstrating the integration of multiple datasets that can accurately assess physical fatigue. The implementation of the multimodal assessment method can prevent fatigue-related accidents and injuries in workplaces, enhance occupational safety, and eventually contribute to increased productivity and economic growth
Geotextile Filtration and Dewatering Characteristics of Acid Mine Drainage and Rare Earth Element Hydraulic Preconcentrate Precipitates
No full textAbstract
Geotextile Filtration and Dewatering Characteristics of Acid Mine Drainage and Rare Earth Element Hydraulic Preconcentrate Precipitates
Zachary Houde
Conventional active Acid Mine Drainage (AMD) treatment methods and manufacturing of Rare Earth Element (REE) Hydraulic Preconcentrate (HPC) precipitate were investigated to identify the particulate filtration and dewatering characteristics. Research was conducted on laboratory manufactured solid precipitate generated from the feedstock of an active AMD treatment plant to determine chemical and physical characteristics with respect to efficiently filter and dewater the materials using woven and non-woven geotextiles. The chemical composition of the raw AMD influent water was evaluated and shown to contain high concentrations of iron, calcium, magnesium, sodium, and aluminum of the total major metals (TMM). The most prevalent of the total rare earth elements (TREE) include yttrium, neodymium, and cerium. Three samples of raw AMD influent water yielded an average TREE concentration of 262.95 µg/L, indicating that this location is a candidate for REE feedstock. Various soil index properties were tested for classification of the AMD sludge and HPC precipitate following American Society of Testing and Materials (ASTM) standards. Results classified the AMD sludge and HPC to be silty sands (SM). Column Filtration Tests (CFTs) were performed on both materials using two different non-woven geotextiles (NW1 and NW2) and one woven geotextile (W1). For AMD sludge, NW2 had the highest average first-exposure filtration efficiency of 80.27% with an average hydraulic conductivity of 1.17x10-3 cm/s; the NW1 fabric showed a slightly lower first-exposure efficiency of 77.20% with an average hydraulic conductivity of 7.15x10-4 cm/s. For HPC, NW1 had the highest average first-exposure filtration efficiency of 79.17% with an average hydraulic conductivity of 1.01x10-4 cm/s; NW2 had an average first-exposure efficiency of 66.91% with an average hydraulic conductivity of 1.75x10-4 cm/s.Research findings led to the construction of a mobile dewatering cell using a repurposed trailer from the WVDEP as well as a composite liner comprised of the NW1 geotextile for filtration of the precipitate slurry and the W1 geotextile for tensile reinforcement of the liner. The dewatering cell is currently deployed on-site at the Richard Mine awaiting field testing, and its intended purpose is to provide a convenient and efficient alternative for dewatering and transporting materials from remote AMD treatment sites to refinement facilities
Learning by Doing, Productivity, and Growth: New Evidence on the Link between Micro and Macro Data
Get PDFSystematic Review Search Strategies: Non-arthritic Hip Diseases AND Psychosocial Factors
Get PDFThe following search strategies were built for a systematic review addressing non-arthritic hip diseases and psychosocial factors. An a priori protocol for this review was developed and registered with PROSPERO (CRD42021248562). The search was originally designed in PubMed, then translated to the other databases searched (Scopus, Web of Science, CINAHL, and SPORTDiscus). Search peer review was performed by Anna Crawford using a modified version of the Peer Review of Electronic Search Strategies guideline. The original search was run on July 12, 2021, with a search update performed on June 21, 2023
Digital Terror Crimes
Get PDFTerror actors operating within armed conflict have weaponized social media by using these platforms to threaten and spread images of brutality in order to taunt, terrify, and intimidate civilians. These acts or threats of violence are terror, a prohibited war crime in which acts or threats of violence are made with the primary purpose of spreading terror among the civilian population. The weaponization of terror content through social media is a digital terror crime.This article is the first to argue that the war crime of terror applies to digital terror crimes perpetrated through social media platforms. It situates digital terror crimes within the existing jurisprudence on terror at ad hoc international and hybrid criminal tribunals. Terror is an autonomous war crime within international criminal law, but all previous convictions for terror have occurred within the context of an underlying criminal act. Digital terror crimes are different: The underlying act of social media use is not necessarily a war crime outside the crime of terror. In addition to examining the ways that digital terror crimes can be committed during armed conflict, this article considers the various actors who could be implicated in the perpetration and distribution of digital terror
Gendered orientalism and the agency of Syrian, Muslim women refugees
Get PDFOrientalist discourses have long recirculated the idea that Muslim women are oppressed victims of Islam; an idea that has denigrated Muslims and positioned white, Christians as superior. For Muslim women refugees specifically, the gendered orientalist discourse of victimization has reappeared on both sides of the debate on Syrian refugee resettlement in the United States (U.S.) (and other Western states). Within anti-resettlement circles, the narrative of Muslim women as oppressed victims has been leveraged as a reason to stop Syrian refugee resettlement; based on a rationale that their lifestyles and values are incompatible with liberal, Western societies. Pro-resettlement circles, on the other hand, often position Muslim women\u27s victimization as a reason to resettle them, because these women need to be ‘saved’ from both war and gender oppression. In other words, the same homogenizing essentialism that positions Muslim women as victims has been used to both reject and to support Muslim refugee resettlement. Yet the representations of Muslim women as oppressed victims of Islam exist in stark contrast to the strong, capable, and resilient Syrian Muslim women refugees scattered across Southwest Asian and North African (SWANA), Europe, the U.S., and elsewhere. Building from postcolonial and feminist literature, I illustrate the ways that gendered orientalism has fueled both sides of the Syrian refugee resettlement debate. Then, I review literature on Islamic feminism and Muslim women\u27s agency, noting its divergences from mainstream Western feminism. Lastly, drawing from interviews I conducted with Syrian Muslim women refugees in Jordan, I highlight the disconnect between the discourses on Syrian refugees in the U.S. and the lives of these women who are coping with the traumas of war and displacement with incredible strength and determination; and they have done so in part through their faith
Symptoms of anxiety, trauma, depression, and obsessive-compulsive disorders in a subsequent pregnancy following a previous pregnancy loss
No full textPregnancy loss is a common and intense personal event that has been found to be a risk factor for increased symptoms of mood, trauma, obsessive-compulsive and anxiety disorders in subsequent pregnancies. Using a self-report online survey, the current study hypothesizes that levels of anxiety, trauma, and obsessive-compulsive symptoms will be higher in pregnant individuals who had a pregnancy loss in their most recent previous pregnancy (n= 61) when compared to pregnant individuals whose most recent previous pregnancy resulted in a live birth (n= 62). Participants responded to an online questionnaire asking about reproductive and mental health history, symptoms of perinatal distress (anxiety, trauma, depression, and obsessive-compulsive), as well as measures of psychological vulnerabilities (perfectionism, self-compassion, and perinatal grief). Study findings demonstrate that individuals with a recent pregnancy loss experienced significantly more depressive symptoms compared to individuals with a recent live birth. Results of moderation analyses suggest that the experience of a pregnancy loss in the most recent previous pregnancy compared to the experience of a live birth strengthens the inverse relationship between self-compassion and perinatal depression. A small to medium effect in the anticipated direction was found between symptoms of perinatal anxiety and previous pregnancy outcome, however, the effect did not reach statistical significance. Contrary to hypotheses, a significant relationship was not found between previous pregnancy outcome and trauma or obsessive-compulsive symptoms. Perfectionism and grief were positively associated with perinatal anxiety, trauma, depression, and obsessive-compulsive symptoms in both the loss and live birth groups. Self-compassion was inversely associated with perinatal anxiety, trauma, depression and obsessive-compulsive symptoms in both the loss and live birth groups. Overall, our study results suggest that the experience of loss in the most recent pregnancy is significantly associated with symptoms of depression in subsequent pregnancies
Return to Soil
Get PDFThis document outlines my artistic research on building a symbiotic relationship with land throughout life and death, eco-philosophy, and the significance of natural decomposition. It explores green burial practices in Western society, delves into the history of basketry, and draws inspiration from the mutualistic effort of returning our organic energy to the Earth. The recontextualization of what “death” is and reciprocal outlooks are central to this work. My aim is to honor this cycle through creations that incorporate plant matter in hopes that, one day, I can create artwork with completely compostable materials.
My art embodies these themes and is rooted in ethical plant foraging and primitive artistic craft, such as weaving, symbolizing our kinship with the environment in both life and death. The ultimate goal is for the ephemeral artwork to embrace decay and decompose in a manner that feeds the soil and the microorganisms it will inevitably encounter, much like ourselves
Novel Membrane Materials for Nutrient Recovery from Nutrient-Rich Resources
No full textGlobal demand for fertilizer production is expanding substantially to meet the food demand of an increasing world population. Anaerobic digestate (AD) of various centralized wastewater facilities contains substantial amounts of ammonium (NH4+) (300-800 mg/L), potassium (K+) (13-120 mg/L), and phosphorus (P) (30-100 mg/L)- based nutrients. In addition to reducing energy costs and CO2 emissions compared to conventional fertilizing raw material manufacturing, recovering nutrients from these waste streams could help mitigate problems such as eutrophication, which otherwise incurs billions of dollars losses to US economy annually. Apart from nutrients, wastewater streams also contain organic pollutants (TOC) (250-1000 mg/L), whose presence can promote micro-organism growth and reduce the value of the derived fertilizers. The aim of this dissertation is to design nanofiltration membranes to selectively separate nutrients (NH4+, K+) and organics from nutrient-rich resources. The first part of this dissertation focuses on developing polyelectrolyte-based membranes by utilizing layer-by-layer (LbL) dip-coating technique to separate two nutrient products NH4+ and K+ from organics. The second part is aimed at designing a crosslinked polyelectrolyte-membrane platform that allows partitioning of NH4+ and K+ in tunable proportions in two product streams. In the final part, an unconventional direct ink writing (u-DIW) technique is introduced to fabricate polyelectrolyte-based membranes, aiming to minimize solvent usage during membrane manufacturing.
To achieve the goal of separating nutrients (NH4+, K+) and organics, the selective layer of various commercial membranes (NF/UF) were modified via layer-by-layer (LbL) deposition of different alternatively charged polyelectrolytes. This modification involved adjusting various LbL parameters, including polymer types, pH, the addition of salt (NaCl) within polyelectrolytes, polymer cross-linking, etc. Such modifications resulted in membranes with diverse properties and demonstrated a trade-off relation between nutrient passage and nutrient/organic selectivity. The findings from this study indicates that both size and charge of the membrane play a vital role in achieving high nutrient/organic pollutant selectivity.
While the first part of this dissertation focused on separating nutrient and organics, the second part is aimed to partition two nutrients - NH4+ and K+, using a novel membrane surface-modification approach. NH4+ and K+ are two critical fertilizer raw materials and achieving selective separation between them would offer the flexibility to tune the nutrient (N:K) ratio, enabling a final product suitable for a diverse range of fertilizing applications. Separation of NH4+/K+ is intrinsically challenging since the hydrated radii of both NH4+ and K+ are identical (0.33 nm) with a slight difference in hydration energy (~10 KJ/mol) between them. To achieve high NH4+/K+ selectivity, polyelectrolyte surface modification is applied to existing commercial membranes, followed by controlled covalent crosslinking. This dissertation presents a fundamental framework of designing crosslinked polyelectrolyte membranes to achieve selective separation between NH4+ and K+. Furthermore, the critical mechanism associated with this separation is briefly elucidated.
In this dissertation, conventional LbL dip-coating was primarily employed to fabricate polyelectrolyte membranes for nutrient recovery applications. This method has a disadvantage of large solvent (water) usage during membrane fabrication. To address this issue, the last part of this dissertation aims to fabricate polyelectrolyte multilayer (PEM) films using an unconventional direct ink writing (u-DIW) technique, which allows the printing of polyelectrolytes via capillary action, without any assistance of external pressure. Here, PEM films were fabricated by tuning various polyelectrolyte parameters such as molecular weight, deposition time, pH, etc. The critical parameters associated with u-DIW films were compared against traditional dip-coated films and found to be very similar, while the u-DIW requiring ~10X less solvent (water) usage compared to dip-coating for fabricating membranes. The findings from this dissertation indicate that polyelectrolyte films fabricated by using this technique could potentially be applicable to a wide range of water treatment applications, including nutrient recovery and desalination, as well as to biomedical applications such as drug delivery and protein adhesion.
In summary, this dissertation presents a novel strategy of recovering two nutrient ions (NH4+ and K+) from wastewater. The most unique contribution of this dissertation is the development of a novel crosslinked polyelectrolyte-based membrane platform for the separation of same sized monovalent nutrient (NH4+/K+). In addition, the applications of polyelectrolyte multilayer NF membranes were also demonstrated for nutrient/organic separations. Furthermore, a novel strategy for fabricating polyelectrolyte film was shown by utilizing an unconventional direct-ink writing technique, which holds the potential of enabling widespread adoption of LbL in various separation and biomedical applications