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Magnesium (Mg) is an essential mineral that is important for bone health, energy production, and vasodilation; however, in the American diet, Mg intake is consistently below the Recommended Dietary Allowance (RDA). The aims of this project were to 1) assess which dietary form of Mg has the greatest bioavailability, 2) determine the effects of Mg depletion upon metabolic rate and energy expenditure, and 3) determine if Mg depletion alters vascular function. Sixty-four male C57BLK/6J mice were split into 4 groups for tissue concentration studies. One group consumed a diet containing a concentration of 100mg/kg Mg Oxide (n=22) for 3 weeks to produce Mg depletion. The other groups followed the same 3 week Mg depletion protocol (100mg/kg Mg Oxide), but then were given either 500mg/kg Mg Citrate (n=10), 500mg/kg Mg Malate (n=10), or 500mg/kg Mg Bisglycinate (n=22) for 1 week to replete Mg status. Mg Citrate and Mg Bisglycinate restored heart tissue Mg to equivalent concentrations while Mg Malate actually reduced heart Mg tissue concentration by 64% (p
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Suppose G is an arithmetic group defined over a global field K, that the K-type of G is An with n at least 2, and that the ambient semisimple group that contains G as a lattice has at least two noncocompact factors. We use results from Bestvina-Eskin-Wortman and Cornulier-Tessera to show that G has a polynomially bounded Dehn function.
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The High Altitude Ice Crystals - High Ice Water Content (HAIC-HIWC) field campaign produced aircraft retrievals of total condensed water content (TWC), hydrometeor particle size distributions, and vertical velocity (w) in high ice water content regions of tropical mesoscale convective systems (MCSs). These observations are used to evaluate deep convective updraft properties in high-resolution nested Weather Research and Forecasting (WRF) simulations of observed MCSs. Because simulated hydrometeor properties are highly sensitive to the parameterization of microphysics, three commonly used microphysical parameterizations are tested, including two bulk schemes (Thompson and Morrison) and one bin scheme (Fast Spectral Bin Microphysics). A commonly documented bias in cloud-resolving simulations is the exaggeration of simulated radar reflectivities aloft in tropical MCSs. This may result from overly strong convective updrafts that loft excessive condensate mass and from simplified approximations of hydrometeor size distributions, properties, species separation, and microphysical processes. The degree to which the reflectivity bias is a separate function of convective dynamics, condensate mass, and hydrometeor size has yet to be addressed. This research untangles these components by comparing simulated and observed relationships between w, TWC, and hydrometer size as a function of temperature. All microphysics schemes produce median mass diameters that are generally larger than observed for temperatures between -10 °C and -40 °C and TWC > 1 g m-3. Observations produce a prominent mode in the composite mass size distribution around 300 µm, but under most conditions, all schemes shift the distribution mode to larger sizes. Despite a much greater number of samples, all simulations fail to reproduce observed high TWC or high w conditions between -20 °C and -40 °C in which only a small fraction of condensate mass is found in relatively large particle sizes. Increasing model resolution and employing explicit cloud droplet nucleation decrease the size bias, but not nearly enough to reproduce observations. Because simulated particle sizes are too large across all schemes when controlling for temperature, w, and TWC, this bias is hypothesized to partly result from errors in parameterized microphysical processes in addition to overly simplified hydrometeor properties such as mass-size relationships and particle size distribution parameters.
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In human breast cancer, molecular gene expression analysis classifies tumors into multiple subtypes: Luminal A and B, Her2, Normal&ndashlike, and Basal. Clinically, human breast cancers are treated based on histological markers, including hormone and growth receptors and special features. Variations in these markers inform both patient survival and treatment options. While the cell of origin for human breast tumors remains unknown, the prevailing hypothesis states that the diversity in human cancer is generated by the epithelial cell type diversity in the mammary gland. Standard breast cancer tumor models selectively express oncogenes in the mouse mammary gland through mammary specific hormone responsive promoters. Unfortunately, these promoters limit transformation to the luminal cell lineage of the breast, bypassing the myoepithelial and stem cell lineages. Using transgenic mice, resulting tumors are not diverse, generating mainly adenocarcinomas with either Luminal or Basal subtypes. We suspected the limited representation of mouse models could be credited to the transgenic mouse tumor cell of origin and that the ability to target a wide range of cells would improve tumor diversity outcomes. In contrast to the established transgenic mouse method, we created a lentiviral infection and transplantation system, where primary mammary epithelial cells are collected from donor mice, infected in vitro with oncogenic lentivirus, and transplanted into a cleared fat pad of recipient mice. With our model, a non&ndashhormone responsive promoter drives polyoma middle T oncogene expression in all mammary epithelial cell lineages. Using this lentiviral infection and transplantation method, we produced several mouse models for rare breast cancer phenotypes including adenosquamous, tubular, spindloid, and lipid&ndashrich. In addition, tumors produced both Basal and Luminal subtypes by microarray analysis. The most striking rare tumor phenotype was the lipid&ndashrich. This tumor secretes fats and milk protein into vacuoles, giving it a distinct morphology. We studied this tumor in depth using histological stains, microarray, and transplants to compare its features with the developmental state of pregnancy in the mammary gland, especially to the alveolar cell type. Finally, we propose an oncogenic targeting system to determine if the alveolar cell is a cell of origin for lipid rich tumors.
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Industrial electrowinning systems are by nature complex, and it can be challenging to evaluate the effects of parametric variation experimentally in production environments. Finite element simulations provide an alternative to physical experimentation. However, simulation of these systems are resource intensive and require coupled multiphysics interactions to accurately model. Despite these challenges, simulation can provide a cost effective means for improvement and optimization. To make it easier to improve operational efficiency and reducing electrowinning costs a model was developed using COMSOL Multiphysics finite element analysis (FEA) software. This work reviews the literature published on the subject providing context to the potential advances in approach. The proposed modeling strategy is presented, beginning with the Nernst--Planck equation describing the migration, convection and diffusion of ionic constituents in an electrolyte. This was coupled with a two-phase computational fluid dynamics (CFD) model to accurately describe mass transport in the system. This coupled approach will allow for accurate deposit morphology modeling. Further, roughness, operational cost and various stochastic methods will be incorporated to describe shorting and cost impact. The objective of this work is to provide a validated, more advanced model to determine the effects of operational parameters on electrowinning performance to facilitate optimization.
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The partial nitritation/anammox (PN/A) process, although found to be an energy and cost-effective process, is not well understood yet. This study was carried out to provide a better understanding of PN/A reactors with suspended and attached growth configurations for treating different waste streams that have potential stress factors. Two PN/A reactors with different configurations were successfully initiated to investigate the difference of suspended growth reactor (SR) and attached growth reactor (AR) in nitrogen removal and the overall microbial composition. During the 300 days of operation, both reactors showed a similar nitrogen removal rate at 35°C and 21°C, and harbored similar communities dominated mainly by three phyla: Chloroflexi, Planctomycetes, and Proteobacteria. To further study the external stress effect on the PN/A performance, the suspended growth reactor was kept at 35°C to 21°C and finally at 13°C.. It was confirmed that lower temperature or sulfide content as low as 5 mgS L-1 could eliminate both Nitrosomonas europaea related ammonium oxidizing bacteria (AOB) and Ca. Brocadia sp. affiliated anammox bacteria (AMX). The activity of AOB was inversely correlated with amoA gene expressions. Just the opposite was found with the hzsA gene expression since it correlated well with the activity of AMX. Additionally, anammox process was applied to treat poststruvite precipitated urine in two-stage and single-stage systems. It was found that coupling the struvite precipitation and PN/A process, 99% recovery of phosphorus and up to 80% removal of nitrogen could be achieved. Compared to the two-stage system, the single-stage reactor had a lower nitrogen removal rate. Also, a pilot-scale PN/A reactor was designed and fabricated to treat reject water in a 300 gal sequencing batch reactor at room temperature. The reactor was successfully started and was able to remove 0.164±0.086 kgNkgVSS-1d-1, indicating a relatively high bacterial activity at room temperature. In conclusion, this study evaluated the feasibility and sustainability of the PN/A system in treating different waste streams containing high ammonium. It provided a better understanding of startup and operation strategies for the full-scale installations of anammox in wastewater treatment plants.
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MicroRNAs (miRNAs) are small, noncoding RNA regulators of gene expression that have many important functions within the immune system. While various critical immunologic functions for specific miRNAs have been uncovered, less is known about the roles of these molecules within the intestinal and adipose microenvironments. Recently, many studies have described the complex intestinal interface, which contains host immune cells and epithelial cells interacting with the microbiota in a manner that promotes symbiosis. Further, there is emerging evidence that miRNAs have evolved to fine tune host gene expression networks and signaling pathways that modulate cellular physiology in the intestinal tract. Here, I first review the present knowledge of the influence miRNAs have on both immune and epithelial cell biology in the mammalian intestines and the impact this has on the microbiota. Next, my work demonstrates the role of one specific miRNA, microRNA-146a (miR-146a), in intestinal homeostasis and disease. miR-146a has previously been shown to have anti-inflammatory function within the immune system and is required to downregulate inflammation in mammals. I find that this miRNA constrains multiple parameters of intestinal immunity and increases murine colitis severity. Further, because miR-146a regulates intestinal homeostasis and populations of the gut microbiota, I hypothesized that this molecule may also be important in regulating immunometabolism in a model of diet-induced obesity. I demonstrate that miR-146a is required to prevent obesity, diabetes, and metabolic disease during high-fat diet. miR-146a was found to regulate multiple networks of gene expression in adipose tissue macrophages both during dietary homeostasis and metabolic disease, and these miR-146a-dependent pathways converge upon inflammation and cell metabolism. Altogether, miR-146a constrains immune responses both within the intestine and adipose tissue, and can both prevent or promote disease, depending on disease and context. This institutes the importance of studying miRNA functions within multiple tissues types and disease contexts, as novel roles for these molecules may be established in various situations.
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Primary breast carcinoma is the most common type of cancer among women and radiodermatitis a frequent complication of treatment. The study aims were to examine the feasibility of measurements of radiodermatitis and gain a better understanding of quality of life (QOL) among 40 women with grade 0-III breast carcinoma receiving radiotherapy at a community cancer center. Study design feasibility, clinician-measured breast length, and multiple assessments of breast radiodermatitis were explored in a pilot study. Maximum radiodermatitis score significantly correlated with breast length (p =.04), and with the following breast areas: upper inner quadrant (p=.04), upper lateral quadrant (p=.02), and lower lateral quadrant (p=.02), inframammary fold (p=.001). Clinician-measured breast lengths and participant-reported bra cup sizes were discordant estimates of breast size. Change in skin-related and global QOL between baseline and at week 5 on radiotherapy was measured using the Dermatology Life Quality Index (DLQI) and the Quality of Life Instrument-Breast Cancer Patient Version. The relationship between, and factors associated with, skin-related and global QOL were examined. In general, skin related and global QOL were highly correlated. Skin-related QOL changed profoundly (M=.40, SD=1.19; versus M=3.88, SD=3.55, t(-6.32), p
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Asymmetries in movement and muscle function are ubiquitous and long lasting in those who survive after hip fracture. Enduring asymmetries in lower limb muscle function (i.e., strength and power) have been associated with fall frequency and impaired physical mobility among older adults. Lower limb discrepancies in vertical ground reaction forces (vGRFs) are evident during performance of mobility tasks, including ambulation and transfers from a seated to a standing position. Movement asymmetry during a sit-to-stand task (STST) made a small, independent contribution (r2 = 7%) to stair climb test performance when coupled with gait speed (r2 = 41%), balance confidence (r2 = 4%), and self-reported function (r2 = 4%); while STST asymmetry did not independently predict modified physical performance test score. To date, there is no specific rehabilitation strategy to restore movement pattern and muscle function symmetry after hip fracture. Thus, the potential impact of specific strategies to improve symmetry in vGRF variables during STST performance, and muscle function after hip fracture is unclear. We examined the feasibility and beneficence of High Intensity Task-Oriented strategies designed to improve Strength and Symmetry (HI-TOSS). We determined that asymmetries in strength, power, and vGRFs evident during STST, were each significantly reduced (i.e., improved) with training. Finally, improvements in muscle quality and its components with training after hip fracture have not been tested. We identify the surgical limb to be 10%-15% lower in muscle mass and muscle quality compared to the nonsurgical limb after discharge from usual care. Following HI-TOSS, muscle mass in the surgical limb improved by 9%, muscle strength improved by 21%, and muscle quality improved by 14%. Expectedly, physical performance improved significantly with training (~20% improvement); exceeding established clinically meaningful difference values. In summary, specific strategies to reduce asymmetries in movement and improve muscle function are well-tolerated in community-dwelling older adults after hip fracture and can yield improvements in STST and muscle function symmetry. Substantial improvements in STST performance, muscle function, muscle composition, and physical function are expected with HI-TOSS. Further studies should determine long-term effects and optimal HI-TOSS implementation practices in a restorative effort to enhance recovery after hip fracture.
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Corrosion of aircraft structures is of utmost concern to operators of aging aircraft fleets. Ongoing research abounds in methods to control, prevent, and detect corrosion damage. For corrosion which inevitably manifests on an aircraft surface, however, removal of the corrosion products by mechanical means is a necessary action. This study examines the effects of such corrosion blends on the overall buckling resistance of integrally stiffened upper wing skin panels. Damage parameters considered in this study include center-of-panel blends on the outer skin surface ranging from depths of 0% to 75% of the skin thickness. A relationship was found between the lost load carrying capability of a blended panel and a function of its lost cross-sectional area. It was also found that this relationship can be closely approximated through minor modifications to traditional analytical methods, without the need for more complex numerical methods such as finite element analysis. Although the finite element method is capable of explicitly addressing local surface blends, experimental validation of such results is often expensive, time consuming, and unavailable to the typical structures analyst.
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