Mineralogical and Physico-Chemical Characterizations of Ferruginous Beidellite-Rich Clay from Agadir Basin (Morocco)

The mechanism of formation of detrital, beidellite-rich clay occurring in the Agadir basin (Morocco) is well documented, but its detailed characterization is incomplete which limits its application. The aim of the present study was to provide further details of the mineralogical and physico-chemical characteristics of this clay. Bulk raw clay and its Na+-saturated, <2 mm fraction were characterized using chemical, structural, and thermal techniques. Measurements of induced streaming potential (e.g. particle charge) and of specific surface area and porous volume are reported. The raw clay contained carbonate and quartz as associated minerals along with phyllosilicates (<2 mm particle size). X-ray diffraction and scanning electron microscopy analyses showed that the <2 mm fraction was dominated by a dioctahedral smectite. Because dehydroxylation of this mineral occurred at 510ºC, and because it re-expanded in ethylene glycol after Li+-saturation followed by heating at 240ºC for 24 h, the mineral was shown to be a beidellite rather than montmorillonite. This assertion was further supported by 27Al and 29Si magic-angle spinning nuclear magnetic resonance spectra showing predominantly negative charges in the tetrahedral sheets due to notable Al-for-Si substitutions. The chemical composition of the <2 mm fraction showed an Fe2O3 content which was ~7.52 wt.% greater than those of other beidellite occurrences but not so much that it would be identified as a nontronite. The absence of stretching and bending absorption bands corresponding to characteristic (Fe2OH) units in mid-infrared spectra and their corresponding fundamental overtones or combination bands in near-infrared spectra supported this notion. The structural formula of the beidellite in the present study was determined to be (Si7.51Al0.49)(Al2.99Fe0.68Mg0.33) (Ca0.03Na0.54Mg0.11)O20(OH)4, having dioctahedral ferruginous characteristics with almost 60% of the negative charge found in tetrahedral sheets. The cation exchange capacity determined from the structural formula was ~108 meq/100 g. The specific surface area and total pore volume were ~82.2 m2/g and 0.136 cm3/g, respectively. Interestingly, a detrital rather than a hydrothermal-alteration origin, as reported for other beidellite occurrences, explains its natural abundance and emphasizes the great interest in it

The Harlem Renaissance\u27s Hidden Figure

This project will seek to look at the Harlem Renaissance’s hidden figure, Jessie Fauset. Jessie Fauset was born to an A.M.E. minister and his wife as one of ten children in Camden County New Jersey and raised in Philadelphia. From there she got her college degree and began teaching all over the country. She has written four novels, There is Confusion, Plum Bun, The Chinaberry Tree, and Comedy: American Style, all of which I have read this summer. Each novel focuses on the early twentieth century black family. I will be analyzing these novels under the four themes of passing, acceptance, romance, and Paris/escape. I will also be mapping the characters in the novel on a QGIS system in order to indicate where the majority of the novel takes place and to see if certain characters have more movement than others. I will finally map Jessie Fauset’s life in order to see if her life parallels with the lives of her characters. Mapping consists of a close reading of the novel, identifying locations in the book, creating an excel spreadsheet, and plotting the spreadsheet onto an online map on QGIS

Violent or Non-Violent? What Difference Does it Make in 1960’s Civil Rights Activism and the State?

In this essay, I research the differences between violent and non-violent actors during the civil rights movement and how their methods changed their interactions with the state. For my case study, I chose two violent and two non-violent subjects, as well as two individuals, and two organizations. Those being Martin Luther King Jr. and the Student Nonviolent Coordinating Committee for my nonviolent actors, and Malcolm X and The Black Panther Party as my violent actors. I examine how their methods as individuals and groups changed the way they interacted with Police, The FBI, and the Federal Government such as presidents and congress

Racial Experience as an Alternative Operationalization of Race

The study of human variation is central to both social and biomedical sciences; however, despite agreeing that variation is integral to the human experience, social and biomedical scientists diverge in how variation is theorized and operationalized. Race becomes especially problematic because it is a cultural concept that contains implicit and explicit understandings of how collective bodies differ. In this paper, we propose an operationalization of race that is attentive to both racial experience and human biological diversity—placing them within the same ontological sphere. Furthermore, we argue that this approach can more effectively advance antiracist pedagogy and politics. We argue that human biological diversity does not have to be in opposition to constructivist notions of race. Rather, racial experience is emphasized as an embodied experience that is as real and as valid as biological variation. By focusing on both racial experience and biological diversity, it becomes more feasible to operationalize race and to more fruitfully inform the pedagogy and politics of anti-racism. In such an operationalization, racial experience must be more broadly conceived, that is, it should not always equate to negative outcomes. With the recognition that racial experience has the potential to be something other than damaging, an antiracist anthropology can more effectively address issues pertaining to racial health disparities

Analyzing the Effects of Data Variability & Volume on Predicting Particulate Matter (PM2.5): Insights from a Machine Learning Approach

Accurately predicting PM2.5 concentrations are imperative to the future of public health and environmental policies. Machine learning models incorporating spatial and temporal datasets to predict PM2.5 are often limited by data availability constraints and poor resolution satellite imagery

Soil Fertility Management, a Tool for Sustainable Disease and Weed Control in Sub-Saharan Africa: A Review

Agro-ecosystem health is built on habitat manipulation and fertility enhancement. Similarly, plant nutrient levels altered by fertilization practices can expose crop plants to pests. In addition, diseases, weeds and other pests are principal agricultural losses all over the world. This is particularly devastating particularly in the developing nations of Sub-Saharan Africa, especially Nigeria. Reduction in these losses will not only improve agricultural production but will enhance food security and economic well-being of society. Sole use of synthetic chemicals is economically not a viable option and does not encourage environmental sustainability while land expansion is equally elusive due to urbanization and different forms of development and not environmentally friendly. The most viable and practicable option is integration of different fertility management alternatives that could produce crops on a sustainable bases while ensuring the safety and sustainability of the environment. Integrated Soil fertility Management (ISFM) has proved to be a promising approach to fertility management and sustainable environment. It could be adopted as it provides the needed nutrients for plants, reduce weeds and disease incidences while safeguarding the environment

The Impacts of Learning Assistants on Student Learning of Physics

This study investigated whether and how Learning Assistant (LA) support is linked to student outcomes in Physics courses nationwide. Paired student concept inventory scores were collected over three semesters from 3,753 students, representing 69 courses, and 40 instructors, from 17 LA Alliance member institutions. Each participating student completed an online concept inventory at the beginning (pre) and end (post) of each term. The physics concept inventories tested included the Force Concept Inventory (FCI), Conceptual Survey of Electricity and Magnetism (CSEM), Force and Motion Concept Evaluation (FMCE) and the Brief Electricity and Magnetism Assessment (BEMA). Across instruments, Cohen's d effect sizes were 1.4 times higher, on average, for courses supported by LAs compared to courses without LA support. Preliminary findings indicate that physics students' outcomes may be most effective when LA support is utilized in laboratory settings (1.9 times higher than no LA support) in comparison to lecture (1.4 times higher), recitations (1.5 times higher), or unknown uses (1.3 times higher). Additional research will inform LA-implementation best practices across disciplines.Comment: Physics Education Research Conference Proceedings (PERC 2016

Tau protein is cross-linked by transglutaminase in P301L tau transgenic mice

This is the publisher's version, also available electronically from "http://www.jneurosci.org".The microtubule-associated protein tau is highly soluble under physiological conditions. However, in tauopathies, tau protein aggregates into insoluble filaments and neurofibrillary tangles (NFTs). The mechanisms underlying the formation of tau filaments and NFTs in tauopathies remain unclear. Several lines of evidence suggest that transglutaminase may cross-link tau into stable, insoluble aggregates, leading to the formation of NFTs in Alzheimer's disease and progressive supranuclear palsy. To further determine the contribution of transglutaminase in the formation of NFTs, we compared the levels of cross-linked tau protein from P301L tau transgenic mice that develop NFTs to four-repeat wild-type (4RWT) tau transgenic and nontransgenic mice that do not develop NFT pathology. Immunoprecipitation and immunoblotting experiments show that transglutaminase cross-links phosphorylated tau in the hindbrain of P301L tau transgenic mice but not in mice overexpressing 4RWT tau and nontransgenic mice. Cross-linked, phosphorylated tau from P301L tau transgenic mice runs as high-molecular mass aggregates on Western blots, similar to cross-linked tau from paired helical filaments of Alzheimer's disease. We also used double-label immunofluorescence to demonstrate colocalization of PHF-1-immunoreactive tau and the transglutaminase-catalyzed cross-link in the hindbrain, spinal cord, and cortex of P301L tau transgenic mice. In the spinal cord, 87% of PHF-1-labeled cells colocalize with the transglutaminase-catalyzed cross-link. Additionally, transglutaminase enzymatic activity is significantly elevated in the spinal cord of P301L tau transgenic mice. These studies further implicate transglutaminase in the formation and/or stabilization of NFT and paired helical filaments and provide a model system to investigate the therapeutic potential of transglutaminase inhibitors in tauopathies