The Effects of Size on Ag Nanosphere Toxicity in Macrophage Cell Models and Lung Epithelial Cell Lines Is Dependent on Particle Dissolution

Silver (Ag) nanomaterials are increasingly used in a variety of commercial applications. This study examined the effect of size (20 and 110 nm) and surface stabilization (citrate and PVP coatings) on toxicity, particle uptake and NLRP3 inflammasome activation in a variety of macrophage and epithelial cell lines. The results indicated that smaller Ag (20 nm), regardless of coating, were more toxic in both cell types and most active in the THP-1 macrophages. TEM imaging demonstrated that 20 nm Ag nanospheres dissolved more rapidly than 110 nm Ag nanospheres in acidic phagolysosomes consistent with Ag ion mediated toxicity. In addition, there were some significant differences in epithelial cell line in vitro exposure models. The order of the epithelial cell lines’ sensitivity to Ag was LA4 \u3e MLE12 \u3e C10. The macrophage sensitivity to Ag toxicity was C57BL/6 AM \u3e MARCO null AM, which indicated that the MARCO receptor was involved in uptake of the negatively charged Ag particles. These results support the idea that Ag nanosphere toxicity and NLRP3 inflammasome activation are determined by the rate of surface dissolution, which is based on relative surface area. This study highlights the importance of utilizing multiple models for in vitro studies to evaluate nanomaterials

The Effect of Size on Ag Nanosphere Toxicity in Macrophage Cell Models and Lung Epithelial Cell Lines Is Dependent on Particle Dissolution

Silver (Ag) nanomaterials are increasingly used in a variety of commercial applications. This study examined the effect of size (20 and 110 nm) and surface stabilization (citrate and PVP coatings) on toxicity, particle uptake and NLRP3 inflammasome activation in a variety of macrophage and epithelial cell lines. The results indicated that smaller Ag (20 nm), regardless of coating, were more toxic in both cell types and most active in the THP-1 macrophages. TEM imaging demonstrated that 20 nm Ag nanospheres dissolved more rapidly than 110 nm Ag nanospheres in acidic phagolysosomes consistent with Ag ion mediated toxicity. In addition, there were some significant differences in epithelial cell line in vitro exposure models. The order of the epithelial cell lines’ sensitivity to Ag was LA4 \u3e MLE12 \u3e C10. The macrophage sensitivity to Ag toxicity was C57BL/6 AM \u3e MARCO null AM, which indicated that the MARCO receptor was involved in uptake of the negatively charged Ag particles. These results support the idea that Ag nanosphere toxicity and NLRP3 inflammasome activation are determined by the rate of surface dissolution, which is based on relative surface area. This study highlights the importance of utilizing multiple models for in vitro studies to evaluate nanomaterials

Role of Lysosomes in Silica-Induced Inflammasome Activation and Inflammation in Absence of MACRO

MARCO is the predominant scavenger receptor for recognition and binding of silica particles by alveolar macrophages (AM). Previously, it was shown that mice null for MARCO have a greater inflammatory response to silica, but the mechanism was not described. The aim of this study was to determine the relationship between MARCO and NLRP3 inflammasome activity. Silica increased NLRP3 inflammasome activation and release of the proinflammatory cytokine, IL-1b, to a greater extent in MARCO-/- AM compared to wild type (WT) AM. Furthermore, in MARCO-/- AM there was greater cathepsin B release from phagolysosomes, Caspase-1 activation, and acid sphingomyelinase activity compared toWT AM, supporting the critical role played by lysosomal membrane permeabilization (LMP) in triggering silica-induced inflammation.The difference in sensitivity to LMP appears to be in cholesterol recycling since increasing cholesterol in AM by treatment with U18666A decreased silica-induced NLRP3 inflammasome activation, and cells lacking MARCO were less able to sequester cholesterol following silica treatment. Taken together, these results demonstrate thatMARCO contributes to normal cholesterol uptake in macrophages; therefore, in the absence ofMARCO, macrophages are more susceptible to a greater inflammatory response by particulates known to cause NLRP3 inflammasome activation and the effect is due to increased LMP

Tertiary Treatment of Wastewater Using Oxidation Ponds

The purpose of the project was to determine the value of using lagoons as a supplemental process for treating the effluent from an activated sludge wastewater treatment plant. Only tentative conclusions can be suggested since the project was not carried to completion. It appears that lagoons will have only minimal effect on the amounts of total nitrogen and phosphate in the plant effluent, although conversion of a portion of the ammonia to nitrate can be expected. However, the concentration of ammonia was never lower than that required by EPA guidelines. Some reduction of soluble BOD appears to occur, perhaps through conversion to new cell material. Suspended solids concentrations can be expected to increase during periods of algae growth. The numbers of both fecal and total coliform bacteria decreased substantially during the detention period provided by the lagoon system. Although not confirmed, it was concluded that the most probable cause for the decrease was the intensity and duration of sunlight. The lagoon served very effectively as a buffer between the treatment plant and the receiving stream, providing a considerable measure of protection to the stream even during those periods during which the plant was by-passing a portion of the inflow

Academic Agenda, Goal Setting, and African American Male Student Persistence at a Predominantly Black Institution

Low African American male student graduation rates in the United States have been a concern for higher education administrators, and more strategies to address their challenges are needed. This basic qualitative study addressed the experiences of African American male students who persisted to graduation at a predominantly Black institution in the northeastern United States. The institutional departure model and goal setting theory formed the conceptual framework for the study. Nine African American males who graduated from the institution described their experiences with academic goal setting and a graduation agenda, through one-on-one interviews. Key findings included the challenges of financial concerns, making supportive connections, and being engaged with university life. Goal setting and pursuing a graduation agenda were supported by interacting regularly with diverse faculty and staff, having work study positions, and participating in athletics and student organizations. Moments of individual connection and support from staff and faculty members helped students pursue academic goals. The project constructed to address the gaps is a 3-day professional development curriculum. Professional development is necessary to ensure all members of campus are focused on the orientation of first year students and their families to support retention through graduation. Academic agenda and goal setting can and should occur across campus and in multiple settings. Positive social change implications of the project include increased stakeholder awareness of supports necessary to retain African American male students in predominantly Black institutions

The general caloron correspondence

We outline in detail the general caloron correspondence for the group of automorphisms of an arbitrary principal $G$-bundle $Q$ over a manifold $X$, including the case of the gauge group of $Q$. These results are used to define characteristic classes of gauge group bundles. Explicit but complicated differential form representatives are computed in terms of a connection and Higgs field.Comment: 25 pages. New section added containing example

Sort and Sift, Think and Shift: Let the Data Be Your Guide An Applied Approach to Working With, Learning From, and Privileging Qualitative Data

The Sort and Sift, Think and Shift qualitative data analysis approach is an iterative process where analysts dive into data to understand its content, dimensions, and properties, and then step back to assess what they have learned and to determine next steps. Researchers move from establishing an understanding of what is in the data (“Diving In”) to exploring their relationship to the data (“Stepping Back”). This process of “Diving In” and “Stepping Back” is repeated throughout analysis. To conclude, researchers arrive at an evidence-based meeting point that is a hybrid story of data content and researcher knowledge. To illustrate core tenets of Sort and Sift, Think and Shift, we analyzed three focus group transcripts from a study of postnatal care referral behavior by traditional birth attendants in Nigeria; these transcripts came from Syracuse University’s Qualitative Data Repository and were unfamiliar to the analytic team prior to this exercise. We focused on letting the data be our guide into not only the explicit purpose of the interviews, but also into the unexpected discoveries that arise when inquiring about people’s lived experiences. Situating our efforts within an Initial Learning Period, each member of the team closely read each transcript, and then identified powerful quotations that made us pause and take note. We documented what we learned from each transcript in an episode profile which contained diagrams and memos. Episode profiles were shared and discussed across the team to identify key points of interest, such as the role of faith in women’s decision-making processes related to their pregnancy and delivery preferences, and concepts of who bears what knowledge about reproductive health. Our engagement in this analytic exercise demonstrates the applicability of qualitative inquiry and Sort and Sift as flexible approaches for applied research

The caloron correspondence and higher string classes for loop groups

We review the caloron correspondence between $G$-bundles on $M \times S^1$ and $\Omega G$-bundles on $M$, where $\Omega G$ is the space of smooth loops in the compact Lie group $G$. We use the caloron correspondence to define characteristic classes for $\Omega G$-bundles, called string classes, by transgression of characteristic classes of $G$-bundles. These generalise the string class of Killingback to higher dimensional cohomology.Comment: 21 pages. Author addresses adde