Adsorptive studies of the inhibitive properties of ethanolic extracts of Parinari polyandra on Mild steel in acidic media

Communication in Physical Sciences 2019, 4(1): 39-47 Authors: F E Awe, M Abdulwahab & H A Otaru  Corrosion inhibition effectiveness of ethanol extracts of Parinari polyandra for mild steel was investigated using gravimetric and polarization methods. The influence of extract concentrations (0.1g/l to 0.5g/l) and temperatures (303K to 323K) on corrosion and corrosion inhibition were assessed. The results obtained showed that the plant extracts decreased the corrosion rate of mild steel in the acid medium. The corrosion rate decreased with increasing extract concentration for mild steel at 303 K. Inhibition efficiency in all the systems decreased with a rise in temperature, suggesting physical adsorption of the extract constituents on the metal surfaces. Linear polarization studies showed that the plant extract suppressed both the anodic and cathodic half reactions of the corrosion processes, thereby acting as mixed-type inhibitors. Langmuir isotherm was found to be the best isotherm that described the adsorption behaviour of the extract on the surfaces of mild steel at room temperature, whereas the adsorption property at elevated temperature was best described by the Freundlich and Temkin adsorption isotherms. Calculated values of free energy of adsorption, ∆????????????????????, on mild steel in the presence of the inhibitor was found to be within the range expected forphysical adsorption mechanism. Corrosion activation energy (Ea) values for mild steel in the acid solutions increased in the presence of the inhibitor and were found to be less than 80 kJmol-1

Theoretical and Experimental Inhibitive Properties of Mild Steel in HCl by Ethanolic Extract of Boscia senegalensis

The experimental aspect of the corrosion inhibition potentials of Boscia senegalensis was carried out using gravimetric and linear polarization techniques techniques as well as scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), whereas the theoretical aspect was done by using the Density functional theory (DFT) calculations to performed and model the electronic structures of some extract constituents, including Physiosorptive interactions with the Fe surface. The analyses of the experimental results showed that the inhibition efficiency increased with increase in concentration of the inhibitor and decreased with increase in temperature. The efficiency of the extract in HCl (70%).  Thermodynamic parameters revealed that the adsorption of extract onto the metal surface was spontaneous, exothermic and supported the Physical adsorption process. FTIR results showed that the inhibition mechanism was by absorption process, through the functional groups present in the extract and that of the inhibited. Surface morphology also revealed that corrosion product confirmed the protection offered by the extract on the surface of the metal immersed in the acid media. The data obtained were fitted into various adsorption isotherms though the Freundlich isotherm was found to be best fit. Keywords: Inhibition, density functional theory, corrosion, boscia senegalensis

Study of the Inhibitive and Adsorptive Properties of Mild Steel in H2SO4 - Boscia senegalensis Plant Environment

The inhibitive and adsorption properties of ethanol extract of Boscia senegalensis for the corrosion of mild steel in H2SO4 were investigated using weight loss, linear polarization, and scanning electron microscopy techniques. From the result, it was found that the corrosion rate of mild steel to decrease with an increase in the concentration of the inhibitor as well as increase with an increase in temperature of the environment. The inhibition efficiency of the inhibitor increases with increasing concentration but decreases with increasing temperature. The inhibition potential of ethanol extract of Boscia senegalensis is attributed to the presence of saponnin, tannin, phlobatanins, anthraquinone, cardiac glycosides, flavanoid, terpene, and alkaloid in the extract. The adsorption of the inhibitor on mild steel surface was found to be exothermic, spontaneous and is best described by Freundlich and Temkim adsorption model. The calculated values of activation energy, enthalpy of activation, entropy of activation, free energy of adsorption and the trend in the variation of inhibition efficiency with temperature, the mechanism of adsorption of the inhibitor by physical adsorption. Ethanol extract of Boscia senegalensis is a good adsorption inhibitor for the corrosion of mild steel in H2SO4. Tafel polarization analyses indicated that studied plant extract is a mixed type inhibitor. Keywords: boscia senegalensis; polarization; adsorption.

Assessment of rural households’ objectives for gathering non-timber forest products (NTFPs) in Kogi State, Nigeria

This study assessed rural households’ objectives for gathering non-timber forest products in Kogi State, Nigeria, with specific focus on identifying some species of non-timber forest products present in the area, identifying reasons why they engaged in the gathering of the non-timber forest products (NTFPs) as well as determining the relative importance of the identified reasons to the households. One hundred and sixty-eight (168) questionnaires were randomly administered on respondents from four randomly selected local government areas from Kogi West Senatorial District of the State. The study identified some species of NTFPs that were found in the study area. These included locust bean (Parkia biglobosa), water leaf (Talinium triangulare), bitter leaf (Vernonia amygdalina) and a host of others. Also, reasons why these rural households in the study area collected NTFPs were identified. Among the reasons given were food security, self employment, income generation and continuity. The relative importance of the given reasons was also determined and it was discovered that food security was the most important reason the households engaged in NTFPs gathering while continuity objective was ranked least.Key words: Non-timber forest products, household, food security, continuity, Kogi State

Developing affordable and accessible pro‐angiogenic wound dressings; incorporation of 2 deoxy D‐ribose (2dDR) into cotton fibres and wax‐coated cotton fibres

The absorption capacity of cotton dressings is a critical factor in their widespread use where they help absorb wound exudate. Cotton wax dressings, in contrast, are used for wounds where care is taken to avoid adhesion of dressings to sensitive wounds such as burn injuries. Accordingly, we explored the loading of 2‐deoxy‐D‐ribose (2dDR), a small sugar, which stimulates angiogenesis and wound healing in normal and diabetic rats, into both types of dressings and measured the release of it over several days. The results showed that approximately 90% of 2dDR was released between 3 and 5 days when loaded into cotton dressings. For wax‐coated cotton dressings, several methods of loading of 2dDR were explored. A strategy similar to the commercial wax coating methodology was found the best protocol which provided a sustained release over 5 days. Cytotoxicity analysis of 2dDR loaded cotton dressing showed that the dressing stimulated metabolic activity of fibroblasts over 7 days confirming the non‐toxic nature of this sugar‐loaded dressings. The results of the chick chorioallantoic membrane (CAM) assay demonstrated a strong angiogenic response to both 2dDR loaded cotton dressing and to 2dDR loaded cotton wax dressings. Both dressings were found to increase the number of newly formed blood vessels significantly when observed macroscopically and histologically. We conclude this study offers a simple approach to developing affordable wound dressings as both have the potential to be evaluated as pro‐active dressings to stimulate wound healing in wounds where management of exudate or prevention of adherence to the wounds are clinical requirements

A scalable framework for stylometric analysis of multi-author documents

This is an accepted manuscript of a chapter published by Springer in Database Systems for Advanced Applications. DASFAA 2018. Lecture Notes in Computer Science, vol 10827 on 13/05/2018, available online: https://doi.org/10.1007/978-3-319-91452-7_52 The accepted version of the publication may differ from the final published version.Stylometry is a statistical technique used to analyze the variations in the author’s writing styles and is typically applied to authorship attribution problems. In this investigation, we apply stylometry to authorship identification of multi-author documents (AIMD) task. We propose an AIMD technique called Co-Authorship Graph (CAG) which can be used to collaboratively attribute different portions of documents to different authors belonging to the same community. Based on CAG, we propose a novel AIMD solution which (i) significantly outperforms the existing state-of-the-art solution; (ii) can effectively handle a larger number of co-authors; and (iii) is capable of handling the case when some of the listed co-authors have not contributed to the document as a writer. We conducted an extensive experimental study to compare the proposed solution and the best existing AIMD method using real and synthetic datasets. We show that the proposed solution significantly outperforms existing state-of-the-art method

A new patient-derived iPSC model for dystroglycanopathies validates a compound that increases glycosylation of alpha-dystroglycan

Dystroglycan, an extracellular matrix receptor, has essential functions in various tissues. Loss of α‐dystroglycan‐laminin interaction due to defective glycosylation of α‐dystroglycan underlies a group of congenital muscular dystrophies often associated with brain malformations, referred to as dystroglycanopathies. The lack of isogenic human dystroglycanopathy cell models has limited our ability to test potential drugs in a human‐ and neural‐specific context. Here, we generated induced pluripotent stem cells (iPSCs) from a severe dystroglycanopathy patient with homozygous FKRP (fukutin‐related protein gene) mutation. We showed that CRISPR/Cas9‐mediated gene correction of FKRP restored glycosylation of α‐dystroglycan in iPSC‐derived cortical neurons, whereas targeted gene mutation of FKRP in wild‐type cells disrupted this glycosylation. In parallel, we screened 31,954 small molecule compounds using a mouse myoblast line for increased glycosylation of α‐dystroglycan. Using human FKRP‐iPSC‐derived neural cells for hit validation, we demonstrated that compound 4‐(4‐bromophenyl)‐6‐ethylsulfanyl‐2‐oxo‐3,4‐dihydro‐1H‐pyridine‐5‐carbonitrile (4BPPNit) significantly augmented glycosylation of α‐dystroglycan, in part through upregulation of LARGE1 glycosyltransferase gene expression. Together, isogenic human iPSC‐derived cells represent a valuable platform for facilitating dystroglycanopathy drug discovery and therapeutic development

Ancient Lowland Maya neighborhoods: Average Nearest Neighbor analysis and kernel density models, environments, and urban scale

Many humans live in large, complex political centers, composed of multi-scalar communities including neighborhoods and districts. Both today and in the past, neighborhoods form a fundamental part of cities and are defined by their spatial, architectural, and material elements. Neighborhoods existed in ancient centers of various scales, and multiple methods have been employed to identify ancient neighborhoods in archaeological contexts. However, the use of different methods for neighborhood identification within the same spatiotemporal setting results in challenges for comparisons within and between ancient societies. Here, we focus on using a single method—combining Average Nearest Neighbor (ANN) and Kernel Density (KD) analyses of household groups—to identify potential neighborhoods based on clusters of households at 23 ancient centers across the Maya Lowlands. While a one-size-fits all model does not work for neighborhood identification everywhere, the ANN/KD method provides quantifiable data on the clustering of ancient households, which can be linked to environmental zones and urban scale. We found that centers in river valleys exhibited greater household clustering compared to centers in upland and escarpment environments. Settlement patterns on flat plains were more dispersed, with little discrete spatial clustering of households. Furthermore, we categorized the ancient Maya centers into discrete urban scales, finding that larger centers had greater variation in household spacing compared to medium-sized and smaller centers. Many larger political centers possess heterogeneity in household clustering between their civic-ceremonial cores, immediate hinterlands, and far peripheries. Smaller centers exhibit greater household clustering compared to larger ones. This paper quantitatively assesses household clustering among nearly two dozen centers across the Maya Lowlands, linking environment and urban scale to settlement patterns. The findings are applicable to ancient societies and modern cities alike; understanding how humans form multi-scalar social groupings, such as neighborhoods, is fundamental to human experience and social organization

Alterations in PGC1[alfa] expression levels are involved in colorectal cancer risk: a qualitative systematic review

Background: Colorectal cancer (CRC) is a major global public health problem and the second leading cause of cancer-related death. Mitochondrial dysfunction has long been suspected to be involved in this type of tumorigenesis, as supported by an accumulating body of research evidence. However, little is known about how mitochondrial alterations contribute to tumorigenesis. Mitochondrial biogenesis is a fundamental cellular process required to maintain functional mitochondria and as an adaptive mechanism in response to changing energy requirements. Mitochondrial biogenesis is regulated by peroxisome proliferator-activated receptor gamma coactivator 1-? (PPARGC1A or PGC1?). In this paper, we report a systematic review to summarize current evidence on the role of PGC1? in the initiation and progression of CRC. The aim is to provide a basis for more comprehensive research. Methods: The literature search, data extraction and quality assessment were performed according to the document Guidance on the Conduct of Narrative Synthesis in Systematic Reviews and the PRISMA declaration. Results: The studies included in this review aimed to evaluate whether increased or decreased PGC1? expression affects the development of CRC. Each article proposes a possible molecular mechanism of action and we create two concept maps. Conclusion: Our systematic review indicates that altered expression of PGC1? modifies CRC risk. Most studies showed that overexpression of this gene increases CRC risk, while some studies indicated that lower than normal expression levels could increase CRC risk. Thus, various authors propose PGC1? as a good candidate molecular target for cancer therapy. Reducing expression of this gene could help to reduce risk or progression of CRC