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Molecular dynamics simulations were employed to understand the improved thermal conductivity and water boiling heat transfer characteristics of adding single-layer graphene (SLG) to substrates. The 100, 110, and 111 planes of Cu, Ni, Pt, and Si were selected for study based on common heat transfer and graphene-compatible materials. Vibrational density of states data was analyzed in order to view heat flux trends. After equilibration at 300K the temperature was increased to 400K for 3 ns to induce nucleate boiling (~27K wall superheat). It was found that the addition of SLG greatly improved the overall thermal conductivity of the composite substrate, with increases in the 1-2 orders of magnitude range. The temperature gradients for SLG-coated substrates were found to be much lower than bare substrates. Nanoscale boiling curves were produced. The CuG100 case shows a 14% increase in critical heat flux (CHF) (~0.36 GW/m2) over the Cu100 case, and the PtG100 shows a 9% increase (~0.48 GW/m2) over the Pt100 case. The SLG-coated substrates also required less superheat to achieve the CHF condition.
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The wide spectrum of phenotypic diversity found in life on Earth is a result of both environmental and evolutionary drivers. Functional traits are those elements of organismal phenotypes which have an effect on the organism’s performance. Specific trait combinations can reveal ecological strategies that evolved in response to selection pressures. The elemental content of living organisms (carbon (C), nitrogen (N), and phosphorus (P)), represent key functional traits that have a strong influence over organismal form and function. Using a global database of stoichiometric traits of animals from terrestrial, freshwater and marine habitats (n > 5000), I applied hypervolume trait approaches to quantify the overall size and shape of the stoichiometric space of animals to determine differences in stoichiometric niche between animals inhabiting different habitats and animals occupying different trophic guilds. I found that the observed multidimensional trait space of animals was significantly smaller than the potential niche space under null expectations and displayed an elliptical shape due to a significant correlation between C and N contents and independent variation of P content. The stoichiometric trait space of invertebrates and vertebrates occupying different habitats and from trophic guilds varied in their size and shape but displayed significant degrees of overlap suggesting evolutionary constraint over stoichiometric traits. These findings suggest that stoichiometric traits may be evolutionarily conserved in animals because regardless of the habitat in which the animals lived or the trophic guild they occupied, they did not evolve to occupy adjacent space, but overlapped in a large portion of their niche space. We argue that due to these evolutionary constraints, animals converge towards a limited amount of successful stoichiometric trait combinations resulting from trade-offs and covariance.
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The expression of futurity is a prime example of linguistic variation and is conditioned by linguistic and external constraints. The expression of futurity by native speakers (NS) of Spanish has been extensively investigated (e.g., Orozco, 2004, 2007, 2018; Sedano, 1994; Silva-Corvalán and Terrell, 1989). Several studies have focused on the analysis of the periphrastic (PF) and morphological (MF) future forms, while others have included the present indicative (PI). However, studies have not adopted a functionalist, concept-oriented approach (e.g., Bardovi-Harlig, 2007; Kanwit, 2014; von Stutterheim and Klein, 1987) when examining how this linguistic function is used (i.e., adopting a semantics-based view of syntax and morphology, examining all forms that express futurity: PF, MF, PI, and others). Furthermore, only a limited number of studies have examined the expression of futurity by second language (L2) learners (e.g., Gudmestad and Geeslin, 2013; Kanwit, 2014), and heritage speakers (HS) (e.g., Gómez Soler and de Prada Pérez, 2016).In order to address these gaps, the present mixed-methods study examined future time expression among 48 L2 learners (20 intermediate-mid, 14 intermediate-high, 14 advanced) and 40 HSs (5 intermediate-mid, 14 intermediate-high, 21 advanced). Participants completed an interview protocol, a preference task, and a metalinguistic awareness questionnaire. Overall, the data revealed that both L2 learners and HSs favored the PF, LF, and PI and produced a significantly lower rate of the MF, subjunctive, conditional and other verb forms when expressing futurity in Spanish. The developmental patterns regarding the expression of futurity were largely similar in L2 learners and HSs. However, there were differences between the two groups in the frequency of use of certain verb forms. The analysis also revealed that the verb forms employed to express futurity were conditioned by linguistic constraints (temporal distance, type and quantity of temporal adverbials, clause type, semantic type of verb, and markers of certainty) and external constraints (exposure to Spanish dialect, formal education in Spanish, and gender). At the metalinguistic level, overall L2 learners exhibited a more formalized way of explaining their choices based on textbook or instructional-related matters. The study concludes that L2 learners and HSs use a wide variety of verb forms to express futurity, which may reflect the input they are exposed to as well as their language acquisition process. The results and contributions are discussed in the framework of the functionalist approach, grammaticalization, second and heritage language acquisition, and pedagogical implications.
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Many have suggested that the United States healthcare system is broken. Costs are higher than ever, access is limited, and at times quality is questionable. One area of opportunity to lower cost, increase quality, and provide greater access is major joint replacement or reattachment of lower extremity—the most common inpatient surgical procedure for Medicare beneficiaries. Existing research points to emergency department visits, readmissions, and mortality as strong determinants of risk in an inpatient stay for major joint replacement or reattachment of lower extremity. For the current study, approximately 2.3 million inpatient claims were ingested from Medicare, resulting in 74 187 major joint replacement claims being extracted, cleansed, processed, and transformed. For each claim, emergency department visits, readmissions, mortality, and length of stay were calculated, along with the creation of an ICD crosswalk from 9 to 10 and Elixhauser Comorbidity Indexes for mortality & readmissions. A novel algorithm was developed to determine the risk of each claim. SAS Enterprise Miner, MATLAB, and MLJAR were used to mine the claims using supervised machine learning algorithms, and Tableau was used to visualize correlations and create 2D plots. This research provided the following insights: Matlab’s Ensemble Boosted Tree algorithm predicted the novel risk 8.out of 10 times across both the training and test dataset, proving its portability and reliability. Consistently, the physicians, provider (hospital), claim payment, type of admission and beneficiary county yielded the strongest predictor strength in predicting the outcome novel risk derived from emergency department visits, mortality, and readmissions. These predictors present areas of opportunity to lower cost, increase access, and improve quality by being used as indicators for early warning & surveillance systems for case workers, clinicians, and hospital administrators. Furthermore, machine learning models utilized in value-based care can assist healthcare leaders, payers, and providers with decision making on which care models may be most effective in facilitating associations to data on outcomes about patients with the highest risk profiles—specifically to identify which patients to follow more closely, which physicians and hospitals have the most successful results, and which geographic areas have differing results. Additionally, white females made up over 60% of observations, and both white females and males had the costliest claim payments. Lastly, obesity and hypertension (complicated & uncomplicated) were the most frequent comorbidities across gender, race and age group.
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Although only adopted recently, the use of ultrasound in anesthesia practice has been defined through its reduction in complications, increased effectiveness of regional anesthesia, and enhanced quality of central venous catheter placement. As noted by the Council on Accreditation (COA), Student Registered Nurse Anesthetists (SRNA’s) should have ultrasound education incorporated into their curriculum for it use both in regional anesthesia as well as central venous catheter placement. The purpose of this study was to determine whether incorporating an ultrasound educational workshop for novice SRNA's at the Rutgers Nurse Anesthesia Program (RNAP) would increase their clinical confidence for the use of ultrasound in peripheral nerve blocks. Using a pretest posttest interventional study, 26 SRNA underwent a workshop consisting of both a didactic lecture and supraclavicular peripheral nerve block simulation. Confidence levels of SRNA's were shown to increase by (x) amount between the pretest and posttest in which significance level of <0.001 was found. The findings concluded that the use of ultrasound education in regards to regional anesthesia is beneficial for novice SRNA's.
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This thesis examines discursive and material practices of coupling nature with redemption and rehabilitation in the carceral state through sustainability initiatives, particularly agriculture education programs. I explore scholarly and popular debates surrounding the Prison Industrial Complex (PIC) and U.S. mass incarceration; sustainability and its ties to agrarianism; and the growing field of “green criminology” and carceral reform, or “carceral humanism” to suggest the significance of their intersections for how we imagine the work of carceral agriculture education programs. I then attempt to historicize literature demonstrating contradictions in the sustainability movement and mass incarceration by evaluating them through debates surrounding the Physiocrats, Thomas Jefferson, as well as commodity fetishism (specifically Henri Lefebvre’s specific reference to fetishizing nature) to explore the debates’ influences and significances, as well as how we might rely on these debates to think about the role of carceral agriculture education programs differently. I then examine four distinct carceral agriculture education programs, how their goals and methods differ or relate, as well as their use of and reliance on agriculture to achieve said goals. From there, I trace a longer history of agriculture at Rikers Island to show the contradictory history of agrarian imaginaries versus humanitarian crises at the New York City jail. Finally, I argue that the example of Rikers should encourage us to consider such programs in the context of reform projects more broadly, as well as look to some of the programs’ aspirations to consider how they can be taken up differently.
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The Quietest Night and Other Songs is a collection of poems that considers the relationships between Jewish identity, Holocaust archives, queerness, and broadly, ancestry and grief.
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Heteroaggregation, the process of aggregation between dissimilar particles is becoming increasingly popular due to the versatile applicability of heteroaggregates. The specific requirements of these widespread application areas require customized heteroaggregates with unique set of properties related mainly to the size and composition of these heteroaggregates. This has created an immense need for a developed understanding of the heteroaggregate process. However, research on heteroaggregates have been very limited, even fundamental questions pertinent to the mechanism of heteroaggregation process remain unanswered to date. The goal of this work is to study and understand the heteroaggregation process both at particle scale to answer some of these fundamental queries about heteroaggregate structure and composition and also use that knowledge to advance the development of process scale models of heteroaggregation. The first aim of this study is to develop a population balance model (PBM) for the second stage of the heteroaggregation process or the agglomeration stage to predict final heteroaggregate particle size distribution (PSD). The model is also used to study the effect of different parameters on the important forces in the system such as electrostatic, van der Waals and hydration force to understand factors that lead to a faster agglomeration dynamics. The model is validated by comparing with experimentally measured final heteroaggregate PSD. The second objective of this work is to develop a model for the first stage of the heteroaggregation process or the layering stage where smaller nanoparticles layer on a larger microparticle and affect its properties, thereby making it more susceptible to aggregation with other such particles in the second stage of heteroaggregation. The model results are compared with the experimental study of monoaggregate structure performed by scanning electron microscopic imaging of the same. This is essential for understanding factors that regulate and limit layering, and in turn affect the monoaggregate distribution and consequently heteroaggregate PSD and the presence of different heteroaggregate regimes. Furthermore, these two models are combined to develop an integrated model for both stages of the heteroaggregation process. The progress of the system towards different heteroaggregation regimes have also been simulated and validated experimentally by studying the final heteroaggregate PSD. The third aim of this study is to investigate the adsorption characteristics of the heteroaggregates for the adsorption of oppositely charged heavy metal ions from single ion as well as mixed ion systems which represent real industrial wastewater more accurately than commonly studied single ion systems. The adsorption capacities of the heteroaggregates from three different regimes are also compared with the adsorption characteristics of the individual components of the heteroaggregates to see if the heteroaggregates offer an advantage over the individual adsorbents. The bio-friendly nature, oppositely charged components and an adsorption capacity comparable to that of industrially popular adsorbents make this system a good choice to replace commonly used adsorbents in the future. This study is expected to advance the field of heteroaggregation by answering some of its most fundamental questions and at the same time aid in the utilization of this knowledge to progress towards the production and use of heteroaggregates in real life applications.
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