Occurrence and Toxicity of Hydrocarbon Residues in Crab (Callinectes sapidus) from Contaminated Site

To elucidate seasonal changes in hydrocarbons including polycyclic aromatic hydrocarbons (PAHs) due to oil spill, tissues of blue crab (Callinectes sapidus) were investigated. Total petroleum hydrocarbons (n-alkanes) concentrations ranged from 0.17-0.32ìg/gdw and 0.28-0.62ìg/gdw during the dry and wet seasons respectively. Thetissues accumulate a complex spectrum dominated by heavier hydrocarbons, alkylsubstituted and PAHs. The impact of biogenic contribution through dietary uptake was related to the elevated levels, particularly of the PAHs. Studies of other site specific, resident organism are recommended in order to be able to establish the extent of toxicity

How Teacher and Student Leader Collaboration Contribute to Learning

The collaboration between teacher and student leader as a possible factor contributing to learning outcomes remains under-researched. To understand the combined efforts of teachers and student leaders toward attaining teaching outcomes, this paper addresses the following questions: What are the value-added dimensions of the teacher toward achieving learning outcomes? How do student leader activities contribute to the achievement of learning outcomes? Without making any claim to tight causal relationships, this paper argues that the effective involvement of student leaders in the teaching process has considerable effects on learning. These effects do not only revolve around student development (for example leadership skills, and citizenship awareness in terms of rights, duties, and responsibilities), but also on the teaching and learning output (Heck, & Hallinger, 1999). Undeniably a common acceptance is that the teacher is permanently the leader while students are mere followers, who do not share teaching and learning behavior when it comes to the exhibition of power and authority within the classroom social environment. Nevertheless, this research reveals how collaboration between teachers and student leaders may improve students’ academic outcomes

Utilizing in Silico and/or Native ESI Approaches to Provide New Insights on Haptoglobin/Globin and Haptoglobin/Receptor Interactions

Haptoglobin (Hp), an acute phase protein, binds free hemoglobin (Hb) dimers in one of the strongest non-covalent interactions known in biology. This interaction protects Hb from causing potentially severe oxidative damage and limiting nitric oxide bioavailability. Once Hb/Hp complexes are formed, they proceed to bind CD163, a cell surface receptor on macrophages leading to complex internalization and catabolism. Myoglobin, (Mb) a monomeric protein, that is normally found in the muscle but can be released into the blood in high concentrations during myocardial injury, is homologous to Hb and shares many conserved Hb/Hp interface residues. Both monomeric Hb and Mb species present potential risks, yet their interactions with Hp have not been extensively studied or are a matter of controversy, respectively. To predict possible interactions of monomeric globins with Hp, we employed a variety of cost and time effective molecular modeling approaches. Native electrospray ionization mass spectrometry (ESI MS) experiments confirm the modeling results and show that monomeric Hb and Mb bind Hp with a stoichiometry of two globin monomers per Hp tetramer. The ESI MS results also demonstrate the success of our computational approaches to Mb/Hp interactions, motivating us to model Hb/Hp/CD163 complexes. Both CD163 bound Ca2+ and specific CD163 acidic residues are known to be essential for binding specific Hp basic residues resulting in Hb/Hp/CD163 complex formation, but the structural details of Hb/Hp/CD163 interactions are unknown. We therefore constructed experimentally driven molecular models of Hb/Hp/CD163 complexes using molecular docking. In order to understand the role of Ca2+ in Hp/CD163 interactions and dynamics, all-atom molecular dynamics (MD) simulations were conducted for CD163 models in the presence and absence of Ca2+. The molecular models of Hb/Hp/CD163 suggest that Hp basic residues R252 and K262 each interact with a conserved acidic triad (E27, E28, D94) in CD163 domains 2 and 3. A calcium ion is postulated to stabilize this CD163 acidic cluster facilitating Hp recognition. Consistent with this, MD simulations on isolated CD163 domains suggest that Ca2+ bound at a specific site in CD163 preserves the arrangement of the acidic triad and protein structural stability. Our studies demonstrate how molecular modeling and molecular dynamics aided/correlated with mass spectrometry experiments can elucidate the structural basis and dynamics of interactions between Hp, globins and/or CD163. This approach may be useful for designing therapeutics that utilizes the Hb/Hp/CD263 endocytosis pathway and unraveling novel avenues for possible Hp-therapy administration for diseases or complications arising from Mb toxicity

Rebuilding Old Empire: BBC and Indigenous Language Broadcasting in Nigeria

Using the framework of postcolonial and critical cultural studies of communication, this essay examines the rise of BBC indigenous language broadcasting in Nigeria. Taking an interdisciplinary approach from the fields of language studies, media studies, and cultural studies, the essay argues that media and communication contact that occurs between colonists and their previous colonies cannot be taken as coincidental or casual; therefore, the need to combine the local and global in theorizing new frameworks for understanding this complex relationship and the power dynamics that occurs alongside it

Reinventing Black Womanhood: Alternative Media and Identity Discourse in the 2019 Chicago Mayoral Race

This paper examines how a Chicago-based alternative medium covered the 2019 Chicago’s mayoral race. The study uses critical discourse analysis and the theory of Black feminism to argue for the need to examine the multiple identities of Black women and how such identities determine their representation in socio-cultural and political spaces. The findings from this study show that agency is a major part of media coverage and that the identities of Black women are better represented when the women are portrayed as agents in their own stories. These findings provide an alternative narrative to the discourse of Black womanhood which has been racialized and perverted

Modelling and optimization of microneedles for transdermal drug delivery

Microneedle mediated drug delivery is an amalgam of the conventional transdermal patch and the hypodermic needle injection. It offers an improved drug delivery technique without the limitations of the above methods. The ability of microneedles to increase permeability of substances in the skin has been established in the literature. However, a quantitative method for predicting the performance of microneedle devices prior to their fabrication is yet to be fully developed. The contribution of this research is a theoretical framework for modelling and optimizing microneedle array design to obtain desired drug delivery rate while taking into account the transport and mechanical properties of the skin. This is achieved by exploring various theories surrounding transdermal drug transport. The existing theories are then used to develop models to link the microneedle array design parameters with drug transport properties such as permeability and drug concentration in blood. Numerical simulations and theoretical analyses that are carried out in this PhD research indicate that microneedle design has a significant effect on drug delivery. An algorithm was developed for solving the series of equations presented, thus obtaining a framework which is applied to predict performance of microneedle arrays in vivo. Some practical scenarios are also simulated to demonstrate the applicability of the developed framework. For example, numerical simulations of transdermal delivery of Fentanyl show that varying the design parameters such as penetrated length of microneedle and the tip radius of microneedles affected the peak blood concentration. Similarly, the developed framework was used to obtain the optimum microneedle design to calculate the desired peak blood concentration similar to that obtained using conventional patch system. This study is relevant as it provides a better understanding of microneedle mediated drug delivery process and it orchestrates the design and hence, fabrication of more efficient microneedle based drug delivery devices

EFFECT OF COMPUTER-ASSISTED INSTRUCTIONAL PACKAGE (CAIP) ON JUNIOR SECONDARY SCHOOL STUDENTS’ PERFORMANCE IN BASIC SCIENCE IN ONDO, NIGERIA

The study investigated the effect of Computer-Assisted Instructional Package (CAIP) on junior secondary school students’ performance in Basic Science in Ondo West Local Government Area of Ondo State, Nigeria. The study adopted pretest – protest control group in quasi experimental design. Two intact classes comprised of forty (40) students (20 males and 20 females) in junior secondary school II took part in the study. The Basic Science Performance Test (BASPET) was used to collect pre-test and post-test scores of students in the experimental and control groups. The internal consistency of BASPET was 0.79 using Kuder-Richardson formula 21. Descriptive statistics such as mean and standard deviation was used to answer the research questions raised in the study, while the inferential statistics; t-test was used to test the formulated hypotheses at 0.05 level of significance. The results revealed that, students taught with Computer-Assisted Instructional Package (CAIP) performed significantly better than those taught with Conventional Method (CMT) at the post test stage. Based on the findings of the study, it was concluded that, CAIP facilitated greater learning among students. It was therefore recommended that, secondary school science students should be taught using CAIP and also, teachers should be trained to be computer literate by attending seminars, workshops involving computer training to enhance efficient performance.  Article visualizations

#Melanin: How Have Dark-skinned Black Women Engaged In Social Media Hashtags To Affirm, Validate and Celebrate Their Beauty?

There is a growing body of scholarship on the nature of social media and its ability to contest racial identity. Research has greatly focused on hashtag activism and the role of Black Twitter in raising consciousness and constructing counterhegemonic presentations of self. However, there is relatively little academic literature surrounding the ways in which dark-skinned African American women are engaging in hashtags to counter colorist ideologies about darker skin tones. Two focus groups and a qualitative content analysis of Tweets containing the hashtag #MelaninPoppin were conducted to explore the ability of social media hashtags to affirm beauty, and encourage powerful self-defining expressions for dark-skinned African American women. Utilizing bell hooks’ notion of homeplace as a theoretical framework, this study examines how social media hashtags act as digital sites of resistance; where the wounds of colorism can be healed and renewed

GLOBALIZATION AND STOCK MARKET GROWTH IN NIGERIA

The subject of the interrelationship that exists between globalization and stock market growth has been an issue of both theoretical and empirical investigations. The a priori expectation is that globalization will impact positively on stock market growth in Nigeria. This work therefore, attempts to find out if there is any impact globalization has on stock market growth in Nigeria. Data for this work were obtained mainly from secondary sources and analysed with the use of ordinary least square simple regression model. The study shows that globalization through trade liberalization and financial integration had a significant impact on the growth of Nigerian stock market. Also, the study equally shows that globalization promotes regional and global integration of Nigerian stock market. However, the study did not overlook the volatility inherent in globalization