Browsing by Subject "SEM"

Now showing 1 - 8 of 8
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    Antineuroinflammatory Activities and Neurotoxicological Assessment of Curcumin Loaded Solid Lipid Nanoparticles on LPS-Stimulated BV-2 Microglia Cell Models
    (MDPI, 2019-03-25) Ganesan, Palanivel; Kim, Byungwook; Ramalaingam, Prakash; Karthivashan, Govindarajan; Revuri, Vishnu; Park, Shinyoung; Kim, Joon Soo; Ko, Young Tag; Choi, Dong-Kug; Medical and Molecular Genetics, School of Medicine
    Curcumin, which is a potential antineuroinflammatory and neuroprotective compound, exhibits poor bioavailability in brain cells due to its difficulty in crossing the blood⁻brain barrier and its rapid metabolism during circulation, which decreases its efficacy in treating chronic neuroinflammatory diseases in the central nervous system. The bioavailability and potential of curcumin can be improved by using a nanodelivery system, which includes solid lipid nanoparticles. Curcumin-loaded solid lipid nanoparticles (SLCN) were efficiently developed to have a particle size of about 86 nm and do not exhibit any toxicity in the endothelial brain cells. Furthermore, the curcumin-loaded solid lipid nanoparticles (SLCN) were studied to assess their efficacy in BV-2 microglial cells against LPS-induced neuroinflammation. The SLCN showed a higher inhibition of nitric oxide (NO) production compared to conventional curcumin in a dose-dependent manner. Similarly, the mRNA and proinflammatory cytokine levels were also reduced in a dose-dependent manner when compared to those with free curcumin. Thus, SLCN could be a potential delivery system for curcumin to treat microglia-mediated neuroinflammation.
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    Depression and Cancer-Related Fatigue: A Cross-Lagged Panel Analysis of Causal Effects
    (2012-07-03) Brown, Linda F.; Bigatti, Silvia M.; Kroenke, Kurt; Rand, Kevin L.; Stewart, Jesse C.
    Fatigue is one of the most common and debilitating symptoms reported by cancer patients, yet it is infrequently diagnosed or treated. Relatively little is understood about its etiology in the cancer context. Recently, as researchers have begun to focus attention on cancer-related fatigue (CRF), depression has emerged as its strongest correlate. Few longitudinal studies have been done, however, to determine whether causal influences between the two symptoms exist. The aim of the current study was to determine whether depression has a causal influence on CRF and whether reciprocal effects exist. The study used a single-group cohort design of longitudinal data from a randomized controlled trial (N = 405) of an intervention for pain and depression in a heterogeneous sample of cancer patients. To be eligible, participants met criteria for clinically significant pain or depression. A hypothesis that depression would influence change in fatigue after 3 months was tested using latent variable cross-lagged panel analysis, a structural equation modeling technique. A second hypothesis was that fatigue would also influence change in depression over time but at a lesser magnitude. Depression and fatigue were strongly correlated in the sample (i.e., baseline correlation of latent variables was 0.72). Although the model showed good fit to the data, χ2 (66, N = 329) = 88.16, p = 0.04, SRMR = 0.030, RMSEA = 0.032, and CFI = 1, neither cross-lagged structural path was significant. The findings suggest that depression had no causal influence on changes in fatigue in this sample, and fatigue did not influence change in depression. The clinical implication is that depression treatment may not be helpful as a treatment for CRF and therefore interventions specifically targeting fatigue may be needed. Future research should include additional waves of data and larger sample sizes.
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    Image Segmentation, Parametric Study, and Supervised Surrogate Modeling of Image-based Computational Fluid Dynamics
    (2022-05) Islam, Md Mahfuzul; Yu, Huidan (Whitney); Du, Xiaoping; Wagner, Diane
    With the recent advancement of computation and imaging technology, Image-based computational fluid dynamics (ICFD) has emerged as a great non-invasive capability to study biomedical flows. These modern technologies increase the potential of computation-aided diagnostics and therapeutics in a patient-specific environment. I studied three components of this image-based computational fluid dynamics process in this work. To ensure accurate medical assessment, realistic computational analysis is needed, for which patient-specific image segmentation of the diseased vessel is of paramount importance. In this work, image segmentation of several human arteries, veins, capillaries, and organs was conducted to use them for further hemodynamic simulations. To accomplish these, several open-source and commercial software packages were implemented. This study incorporates a new computational platform, called InVascular, to quantify the 4D velocity field in image-based pulsatile flows using the Volumetric Lattice Boltzmann Method (VLBM). We also conducted several parametric studies on an idealized case of a 3-D pipe with the dimensions of a human renal artery. We investigated the relationship between stenosis severity and Resistive index (RI). We also explored how pulsatile parameters like heart rate or pulsatile pressure gradient affect RI. As the process of ICFD analysis is based on imaging and other hemodynamic data, it is often time-consuming due to the extensive data processing time. For clinicians to make fast medical decisions regarding their patients, we need rapid and accurate ICFD results. To achieve that, we also developed surrogate models to show the potential of supervised machine learning methods in constructing efficient and precise surrogate models for Hagen-Poiseuille and Womersley flows.
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    An in-vitro SEM study comparing the debridement efficacy of the EndoVac® system versus the Canal CleanMax® following hand-rotary istrumentation
    (2010) Ricketts, Benjamin P. (Benjamin Paul), 1980-; Vail, Mychel; Legan, Joseph J.; Moore, B. Keith; Spolnik, Kenneth Jacob, 1950-; Zunt, Susan L., 1951-
    This in-vitro, prospective, randomized study microscopically compared the debridement efficacy of negative pressure irrigation with the EndoVac (Discus Dental, Culver City, CA) versus the Canal CleanMax (Maximum Dental, Inc., Secaucus, NJ). Sixty extracted human canines were instrumented using a combination of hand-instrumentation with Lexicon K-type files and rotary instrumentation with ProTaper files. All canals were irrigated with 6.0-percent sodium hypochlorite and 17- percent ethylenediaminetetraacetic acid (EDTA). However, the irrigation/aspiration techniques differed among three groups of 20 randomly selected teeth. Group one (control) was irrigated with only a 12-ml Monoject syringe via 30-gauge side-vented, closed-end needle. Group two was irrigated with the EndoVac system. Group three was irrigated similar to group one, but with the adjunct of the Canal CleanMax system. All teeth were sectioned longitudinally, and the more intact sections were divided into coronal, middle, and apical thirds. Each portion of the canal was photographed with a scanning electron microscope (SEM). The photographs were scored by two independent examiners according to relative amount of debris and/or smear layer present, as well as relative number of patent dentinal tubules. These scores were statistically analyzed using a Krustal-Wallis test and Wilcoxon Rank Sum tests to determine differences between groups. The coronal aspect of root canal walls irrigated with the EndoVac system exhibited significantly less debris and/or smear layer present when compared to the coronal aspect of root canals irrigated with only a standard 12-ml Monoject syringe equipped with 30-gauge ProRinse side-vented, closed-end needle (control). There were no other significant differences in scores between any groups at any location. For all locations combined, the EndoVac system produced significantly cleaner root canal walls as compared to the control. No significant differences were seen between the Canal CleanMax and Control or Canal CleanMax and EndoVac. This study suggested negative pressure irrigation delivery with the EndoVac system during and after hand-rotary instrumentation is more effective in removal of debris and smear layer from the coronal third and combined thirds of root canal walls compared to irrigation with a standard 12-ml Monoject syringe equipped with 30-gauge ProRinse side-vented, closed-end needle.
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    A Structural Equation Modeling-Based Examination of the Private Label Brand (PLB) Consumer Evaluation Process
    (Springer, 2016) Mayer, James Mark; Kelley School of Business
    The goal of this paper is to answer the question “What variables influence consumer private label brand (PLB) evaluations?” We employ structural equation modeling (SEM) in order to analyze a hypothesized process by which consumer-based evaluations of retailer and product category, along with perceived risk of the category and PLB all affect the ultimate PLB brand evaluation. PLBs have been heavily researched in academic marketing research journals but SEM-based research is minimal. Research has generally been conducted using model-building techniques which are then empirically tested using real-world data. Given the complexity of the process, an alternate approach is to use experimental techniques to gain first-hand PLB data and then analyze it using appropriate methodology. The current project represents a step in that direction. While the model is subject to limitations that call its utility into question, it does provide guidance for a future, more theoretically-sound a priori model and resulting SEM analysis.
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    Using community science for detailed pollution research: a case-study approach in Indianapolis, IN, USA
    (Springer, 2023-01) Dietrich, Matthew; Rader, Shelby T.; Filippelli, Gabriel M.; Earth Science, School of Science
    Heavy metal contamination in urban environments, particularly lead (Pb) pollution, is a health hazard both to humans and ecological systems. Despite wide recognition of urban metal pollution in many cities, there is still relatively limited research regarding heavy metal distribution and transport at the household-scale between soils and indoor dusts-the most important scale for actual human interaction and exposure. Thus, using community-scientist-generated samples in Indianapolis, IN (USA), we applied bulk chemistry, Pb isotopes, and scanning electron microscopy (SEM) to illustrate how detailed analytical techniques can aid in interpretation of Pb pollution distribution at the household-scale. Our techniques provide definitive evidence for Pb paint sourcing in some homes, while others may be polluted with Pb from past industrial/vehicular sources. SEM revealed anthropogenic particles suggestive of Pb paint and the widespread occurrence of Fe-rich metal anthropogenic spherules across all homes, indicative of pollutant transport processes. The variability of Pb pollution at the household scale evident in just four homes is a testament to the heterogeneity and complexity of urban pollution. Future urban pollution research efforts would do well to utilize these more detailed analytical methods on community-sourced samples to gain better insight into where the Pb came from and how it currently exists in the environment. However, these methods should be applied after large-scale pollution screening techniques such as portable X-ray fluorescence (XRF), with more detailed analytical techniques focused on areas where bulk chemistry alone cannot pinpoint dominant pollution mechanisms and where community scientists can also give important metadata to support geochemical interpretations.
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    Using community science for detailed pollution research: A case-study approach in Indianapolis, IN, USA
    (Springer Nature, 2022-11-21) Dietrich, Matthew; Rader, Shelby; Filippelli, Gabriel; Earth and Environmental Sciences, School of Science
    Heavy metal contamination in urban environments, particularly lead (Pb) pollution, is a health hazard both to humans and ecological systems. Despite wide recognition of urban metal pollution in many cities, there is still relatively limited research regarding heavy metal distribution and transport at the household-scale between soils and indoor dusts-the most important scale for actual human interaction and exposure. Thus, using community-scientist-generated samples in Indianapolis, IN (USA), we applied bulk chemistry, Pb isotopes, and scanning electron microscopy (SEM) to illustrate how detailed analytical techniques can aid in interpretation of Pb pollution distribution at the household-scale. Our techniques provide definitive evidence for Pb paint sourcing in some homes, while others may be polluted with Pb from past industrial/vehicular sources. SEM revealed anthropogenic particles suggestive of Pb paint and the widespread occurrence of Fe-rich metal anthropogenic spherules across all homes, indicative of pollutant transport processes. The variability of Pb pollution at the household scale evident in just four homes is a testament to the heterogeneity and complexity of urban pollution. Future urban pollution research efforts would do well to utilize these more detailed analytical methods on community-sourced samples to gain better insight into where the Pb came from and how it currently exists in the environment. However, these methods should be applied after large-scale pollution screening techniques such as portable X-ray fluorescence (XRF), with more detailed analytical techniques focused on areas where bulk chemistry alone cannot pinpoint dominant pollution mechanisms and where community scientists can also give important metadata to support geochemical interpretations.
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    Using community science for detailed pollution research: A case-study approach in Indianapolis, IN, USA
    (Springer, 2023-01) Dietrich, Matthew; Rader, Shelby T.; Filippelli, Gabriel M.; Earth and Environmental Sciences, School of Science
    Heavy metal contamination in urban environments, particularly lead (Pb) pollution, is a health hazard both to humans and ecological systems. Despite wide recognition of urban metal pollution in many cities, there is still relatively limited research regarding heavy metal distribution and transport at the household-scale between soils and indoor dusts—the most important scale for actual human interaction and exposure. Thus, using community-scientist-generated samples in Indianapolis, IN (USA), we applied bulk chemistry, Pb isotopes, and scanning electron microscopy (SEM) to illustrate how detailed analytical techniques can aid in interpretation of Pb pollution distribution at the household-scale. Our techniques provide definitive evidence for Pb paint sourcing in some homes, while others may be polluted with Pb from past industrial/vehicular sources. SEM revealed anthropogenic particles suggestive of Pb paint and the widespread occurrence of Fe-rich metal anthropogenic spherules across all homes, indicative of pollutant transport processes. The variability of Pb pollution at the household scale evident in just four homes is a testament to the heterogeneity and complexity of urban pollution. Future urban pollution research efforts would do well to utilize these more detailed analytical methods on community-sourced samples to gain better insight into where the Pb came from and how it currently exists in the environment. However, these methods should be applied after large-scale pollution screening techniques such as portable X-ray fluorescence (XRF), with more detailed analytical techniques focused on areas where bulk chemistry alone cannot pinpoint dominant pollution mechanisms and where community scientists can also give important metadata to support geochemical interpretations.