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SENUFO Culture of Arts from northern Ivory Coast, the southeastern Mali and the western Burkina Faso and in north-western Ghana - (Rytham Pounder)
No full textThis female rhythm pounder was principally used during funerals. As the corpse was carried to the burial ground, elders would pound on the ground with the figures, ritually purifying the pathway for the deceased and calling ancestral spirits. Rhythm pounders are owned by a small subgroup of artisans, the Celibele, who make a living as rope makers and tanners.https://digitalcommons.pvamu.edu/african-sculptures-and-masks/1067/thumbnail.jp
Integrals of Legendre polynomials over half range and their relation to the electrostatic potential in hemispherical geometry
No full textSpherical symmetry is often encountered in many problems in mathematics and physical sciences. On the other hand, cases that involve hemispherical geometry lead to much less studied mathematical situations. In this work, we consider a case study that arises from potential theory where absence of a full spherical symmetry gives rise to expressions involving Legendre polynomials constrained in an interval that is different from the usual range in which they are orthogonal. We use exact mathematical results for the integrals of Legendre polynomials of arbitrary order over half range to obtain analytic expressions for the electrostatic potential created by a solid hemisphere with uniform volume charge density
Mixed Biopolymer Systems Based on Bovine and Caprine Caseins, Yeast β-Glucan, and Maltodextrin for Microencapsulating Lutein Dispersed in Emulsified Lipid Carriers
No full textLutein is an important antioxidant that quenches free radicals. The stability of lutein and hence compatibility for food fortification is a big challenge to the food industry. Encapsulation can be designed to protect lutein from the adverse environment (air, heat, light, pH). In this study, we determined the impact of mixed biopolymer systems based on bovine and caprine caseins, yeast β-glucan, and maltodextrin as wall systems for microencapsulating lutein dispersed in emulsified lipid carriers by spray drying. The performance of these wall systems at oil/water interfaces is a key factor affecting the encapsulation of lutein. The highest encapsulation efficiency (97.7%) was achieved from the lutein microcapsules prepared with the mixed biopolymer system of caprine αs1-II casein, yeast β-glucan, and maltodextrin. Casein type and storage time affected the stability of lutein. The stability of lutein was the highest (64.57%) in lutein microcapsules prepared with the mixed biopolymer system of caprine αs1-II casein, yeast β-glucan, and maltodextrin, whereas lutein microcapsules prepared with the biopolymer system of bovine casein, yeast β-glucan, and maltodextrin had the lowest (56.01%). The stability of lutein in the lutein microcapsules dramatically decreased during storage time. The antioxidant activity of lutein in the lutein microcapsules was closely associated with the lutein concentration
(SI10-130) On Regular Inverse Eccentric Fuzzy Graphs
Get PDFTwo new concepts of regular inverse eccentric fuzzy graphs and totally regular inverse eccentric fuzzy graphs are established in this article. By illustrations, these two graphs are compared and the results are derived. Equivalent condition for the existence of these two graphs are found. The exact values of Order and Size for some standard inverse eccentric graphs are also derived
Small In Number, Large In Impact: The Recruitment And Retention Of Middle School African American Male Stem Teachers
No full textWatson and Smitherman (1996) emphasized the important role African American male teachers can play in schools, particularly in those with African American male students. They argued that these teachers serve as positive role models and provide culturally relevant support. Gay (2020) highlighted that the lack of African American male teachers exacerbates the challenges faced by African American male students.This underrepresentation can lead to feelings of isolation and a lack of engagement. Furthermore, it may contribute to lower academic achievement and fewer opportunities for success among African American male students.
The study sought to determine (1) the perception of the need for African American male teachers in K-12 STEM Education, (2) the perception of African American teachers regarding their personal STEM education based on their decision to enter the teaching profession, (3) their perception of the value and accomplishments as African American male teachers in K-12 STEM classrooms, and (4) their perception of the impact that African American male STEM educators on African American STEM male students.
This study examined the underrepresentation of African American male STEM educators in middle schools. This research study utilized a qualitative design. The conceptual frameworks leading the study were African American Male Theory and Critical Race Theory. The results of this study revealed African American male teachers and preservice teachers’ perspective of their impact as STEM educators not only regarding the field of education but also regarding the STEM disciplines, as it is theorized that positive interaction in STEM areas in middle schools could lead to more African American males to pursue careers in STEM fields. The belief is that the results of this study may reveal the deficit of African American male teachers, specifically in STEM education. Findings from this study may also aid in the recruitment, retention, and incentivization of African American male STEM teachers in K-12 school systems and teacher preparation programs, both traditional and alternative routes.
Keywords: phenomenology, African American Male STEM teachers, Critical Race Theory, African American Male Theory, underrepresentation in STEM education, African American male middle school teacher
Investigation Of Rainfall Patterns And Its Impact On Highway Embankments
Get PDFRainfall-induced slope failure is a common geotechnical hazard in Texas. Rainfall infiltration results in a reduction in soil matric suction and shear strength, leading to the instability of highway slopes. Rainfall intensity and duration have been identified as one of the major causes of earthen slope stability problems. In response to varied rainfall events, the unsaturated soil behavior differs depending on the soil type. The rainfall and soil data were used to develop a pattern which identified the slopes which proved unstable. The objective of this paper is to investigate the influence of different rainfall characteristics on slopes constructed on problematic expansive soil in Harris County (HC), Texas by using the finite element method (for seepage analysis) and the limit equilibrium method (for slope stability analysis). Few soil samples collected from different sources of Harris County were tested in the laboratory to characterize its strength properties. Most critical rainfall events of the HC were identified from the past twenty years rainfall history. Based on the weather radar network evaluation, few critical rainfall events were identified to be vulnerable for slope stability. Out of that, the rainfall intensity and duration during hurricane Harvey was observed much vulnerable for the stability of highway slopes
Chemiluminescence Of Platinum Nanoparticles Using A Green Method For Lateral Flow Immunoassay
Get PDFPlatinum (Pt) is used as a catalyst in many reactions, and platinum nanoparticles (Ptnps) are widely used in the biomedical industry as they show antioxidant, antimicrobial, and anticancer properties. Synthesis of Ptnps can be achieved in many ways. However, green synthesis methods are preferred over traditional ones as they minimize environmental pollution. This research aims to synthesize Ptnps using a green approach and use the synthesized nps in a catalysis reaction.
Nanoparticles were synthesized using chloroplatinic acid hydrate (H2PtCl6) and potassium hexachloroplatinate (IV) (K2PtCl6) and three types of milk obtained from the local grocery stores. The Pt salt and the green source were placed in a shaking incubator at two time points (4 and 72 hours) and at room temperature. The synthesized Ptnps were characterized using UV-Visible spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM/EDS). The average size of the particles was estimated using dynamic light scattering measurements, and the redox properties were measured using cyclic voltammetry.
The results showed that Ptnps were formed using both salts, incubation periods and all green sources. UV-Visible results showed peaks that indicate the formation of Ptnps at both incubation periods for both Pt salts. Peaks were more intense in the samples in the shaking incubator for 72 hours as opposed to the samples that were incubated for 4 hours. The Ptnps of K2PtCl6 salt showed a more intense peak than that of the Ptnps of H2PtCl6 salt in the 72-hour incubation period, and both salts showed similar peak intensities when held in the shaking incubator for 4 hours.
The dynamic light scattering results showed that H2PtCl6 salt produced nanoparticles (Nps) with similar averages for the diameter for both incubation periods, while K2PtCl6 salt Nps was incubated for 4 hours showed smaller sizes than the H2PtCl6 salt held at both incubation periods. K2PtCl6 salt incubated for 72 hours had at least 1/3 lower sizes. This could be because, in K2PtCl6 salt, the potassium ion prevents aggregation. Cyclic voltammetry results showed that the oxidation and reduction peaks vary between salts, time, and the naturally occurring materials.
The SEM/EDS results showed the presence of Pt for both salts at both incubation periods, and the amount of Pt present was higher when the Pt salt was incubated for 72 hours versus 4 hours. The FTIR results for both salts and both incubation periods showed a broad stretch in the functional group region between 2500 and 3550 cm-1. Stretching and bending in this range are indications of the presence of OH groups. Peaks at 2850 and 3300 cm-1, were an indication of the presence of a CH group. The CH stretch intensity varied between the salts and the naturally occurring materials. Results show that Ptnps can be produced in an environmentally friendly way using both H2PtCl6 and K2PtCl6 salts and that K2PtCl6 salt may be a better salt to use when producing Ptnps. Data from multiple experiments showed that Nps of K2PtCl6 was less aggregated than that of the Ptnps produced with the H2PtCl6 salt. The synthesized Ptnps of milk, when used in the chemiluminescence reactions of luminol, showed that it enhanced the activity. In future work, these Ptnps will be tested in lateral flow assay (LFA) experiments that are used in point-of-care testing
(R2024) A New Weighted Poisson Distribution For Over- and Under-Dispersion Situations
Get PDFIn this paper, we propose a four-parameter weighted Poisson distribution that includes and generalizes the weighted Poisson distribution proposed by Castillo and Pérez-Casany and the Conway- Maxwell-Poisson distribution, as well as other well-known distributions. It is a distribution that is a member of the exponential family and is an exponential combination formulation between the weighted Poisson distribution proposed by Castillo and Pérez-Casany and the Conway-Maxwell- Poisson distribution. This new distribution with an additional parameter of dispersion is more flexible, and the Fisher dispersion index can be greater than, equal to, or less than one. This last property allows it to model over-dispersed data as well as under-dispersed or equi-dispersed data. Many other properties of the new distribution are studied in this article. The parameters are estimated by two methods: the least squares and the maximum likelihood methods. The properties of the estimators are not studied because they follow directly. Two examples of application to real data, taking into account situations of overdispersion and underdispersion, are examined