International Annals of Science
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Scattering of Free Electrons with Hydrogen Atoms in Proton Exchange Membrane Fuel Cell System
The objective of this work is to study the Klein-Nishina (KN) cross section during the collision of free electrons and atoms (H-atom and Pt-atom) near the cathode of Proton Exchange Membrane Fuel Cell (PEMFCs). The developed KN cross section was computed using MATLAB shows KN cross section decrease with an increase with the temperature. The maximum KN cross section recorded for single scattering is about -70.2m2 and -66m2 in natural log terms during the collision of free electrons with H-atom and Pt-atom, respectively. The maximum KN cross section recorded for 1ml flow of hydrogen is about -26.6m2 and -22.25m2 in natural log term during the collision of free electrons with H-atom and Pt-atom, respectively
Popcorn Polymers in Butadiene Extraction Units
Several aspects disturb operation of industrial facilities which can cause severe impact on their efficiency and productivity. In some cases, the impact can expose industrial facilities to serious safety concerns. Therefore, Industrial facilities should always plan to invest in reliability and sustainability of their daily operation. Polymerization is one of the unavoidable risks that can be unpredictable and cause several issues to operating facilities. On the other hand, effective proactive plans can be addressed to minimize and eliminate polymerization risks. This article provides introductory information about polymerization of butadiene “Popcorn polymers”, formation mechanism, associated hazard, control and mitigation methodologies
Impact of Genotype × Environment Interaction on Seed Yield and Pod Shattering of Soybean Genotypes in Nigeria
Yield instability and pod shattering are the major problems associated with soybean production in Nigeria. To study Genotype × Environment interaction effects on seed yield and pod shattering behaviour of some soybean genotypes in Nigeria, an experiment was conducted in three (3) environments within the country. In each environment, the experiment was laid out in a randomized complete block design (RCBD) with three replications. During the harvest, pod shattering evaluation was conducted using the sun-dry method. Data were collected on seed yield and pod shattering percentage and analyzed using Additive Main Effect and Multiplicative Interaction (AMMI) and Genotype plus Genotype × Environment Interaction (GGE) bi-plot analyses. Genotypes NCRI SOYAC18, NCRI SOYAC78, NCRI SOYAC9, NCRI SOYAC20, NCRI SOYAC61, NCRI SOYAC22, NCRI SOYAC28 and NCRI SOYAC76, with yields above 1.23 ton/ha recorded high and stable yield across environments. For pod shattering resistance, nine genotypes (NCRI SOYAC3, NCRI SOYAC69, NCRI SOYAC77, NCRI SOYAC29, NCRI SOYAC9, NCRI SOYAC7, NCRI SOYAC67, NCRI SOYAC76 and NCRI SOYAC22) had stable pod shattering resistance across environments. Therefore, only three genotypes (NCRI SOYAC9, NCRI SOYAC22, and NCRI SOYAC76) were stable in both high yield and resistance to pod shattering. Consequently, any soybean breeding programme that involves high yield and pod shattering resistance could consider these three genotypes
Analysis of miRNAs: Biomarkers for HER2-Targeted Breast Cancer Therapy
Breast cancer remains a leading lethal cancer in women globally, with the HER2+ positive subtype associated with a higher chance of therapeutic resistance. Treatments tailored specifically to this subtype, such as targeted therapies, have significantly developed over the past decade. However, the issue of drug resistance to targeted drugs underlines the necessity of better treatment approaches. Recent studies have focused on microRNAs (miRNAs), single-stranded non-coding RNAs, as critical regulators in drug resistance mechanisms. These miRNAs, capable of influencing various cellular processes, have emerged as critical modulators in numerous diseases, including different cancer types, particularly breast cancer. This article reviews current methodologies in the study of miRNAs within the context of HER2-positive breast cancer, from the selection of study models and sample extraction to comprehensive analysis methods. Our objective is to highlight the potential that miRNAs hold as biomarkers capable of regulating drug resistance in this specific cancer subtype. Moreover, we also discuss the importance of integrating advanced study models alongside the latest bioinformatics tools to enrich this research domain. Furthermore, this article evaluates the use of clinical samples and cell line models for studying miRNAs in this field, outlining the advantages and limitations of each method and proposing a refined approach to research design. The main contribution of this work is the establishment of a detailed taxonomy of research strategies that address current challenges while also outlining promising future directions, particularly focused on elucidating the regulatory mechanisms of miRNAs in therapeutic resistance in breast cancer. In addition, by underscoring the necessity of employing a diverse array of study models and capitalizing on bioinformatics advancements, this article seeks to uncover the complex interactions between miRNAs and drug resistance mechanisms in breast cancer. Ultimately, our goal is to pave the way toward overcoming therapeutic resistance, thereby improving the prognosis for patients afflicted with HER2-positive breast cancer
Composition of Mangroves and Mangrove Associates in Barangay Ata Atahon, Nasipit, Agusan del Norte, Philippines
Mangroves are essential components of the coastal biome and have an extremely productive ecosystem. It provides benefits for both the environment and humans. Valuation of the diversity and species composition plays a crucial role in the conservation and protection. This study aimed to assess the composition of mangroves and mangrove associates in Barangay Ata-Atahon, Nasipit, Agusan del Norte, Philippines. Three sampling stations were established with a 50-meter interval in every station. Transect lines of 50 meters were laid perpendicular to the shoreline. The results show that 19 species of mangroves and 5 mangrove associates were recorded. Ceriops decandra was found to be the dominant species with 303 individuals and constituting 36% of the entire mangroves population. While Camptostemon philippinensis, Rhizophora apiculata, Rhizophora mucronata had the lowest number of individuals and made up a combination of 5%. In mangrove associates, Avicennia rumphiana made up 47% of the population and was followed by Avicennia marina (40%). This implied that the study area is less diverse based on the observed species when compared to the 46-mangrove species found in the Philippines alone. Necessarily, reforestation and conservation efforts must be attained to fill the gaps between the community and mangrove sustainability. Thus, determining the species diversity and composition measures ecological status. Mitigations and ecological management must be enacted by the locality to further conserve the mangrove ecosystem
Nature-inspired Material – A Step Ahead in Dental Materials
Glass-ionomer is first choice widely used biomaterial in caries disease. The evolution of dental material science includes insertion of new components into conventional material. A literature-based review outline of biomaterials for dental restorations development was presented in nature-inspired context. This article is a tribute to the entire research community, for all listed and unlisted, involved throughout the ages in the science of dental materials with the key inventions and milestones for humanity well-being on Earth. Results. Since the Neolithic, the human mind has been seeking for a matter to replace missing tooth tissue imitating/mimicking natural organ in appearance and function, what we call biomimetic/biomimicry approach. However, this restoring philosophy does not refer to the natural composition of hard tooth tissues. Possibly, there is another one concept of drawing inspiration from nature for the design of future dental materials. Nature-inspired synthesis goes beyond aesthetic/and anatomical similarities, and delves into the mechanistic, physico-chemical features or structure-phase of natural systems. In this context, pure glass-ionomer might be taken into consideration as a starting material. However, the search for synthetic nature-inspired mesomaterial with a structural-phase composition analogous to enamel/dentine/cementum, transforming into the original host hard tissues, should focus on elongated hydroxyapatite dipole control for creating and organizing into enamel prisms, and the interwoven alignment of perpendicular clusters/bunches in a picket-fence resembling three-dimensional order. The results of previous studies confirming the possibility of the formation of apatite-enamel-like tissue in glass-ionomer are promising. The concept of inclusion of calcium phosphate nanocrystals/substitution of glass filler seems to be forward-looking. The future role of polyelectrolyte organic matrix based on synthetic tooth polypeptides crosslinked with modified analogues of natural adhesives is still undiscovered
Effect of Nitrogen and Phosphorus Levels on Yield of Marvel Grass (Dichanthium-Annulatum L) in Irrigated Condition Under N-W Agro Climatic Zone
The experiment was undertaken during Kharif season of 2019, 2020 and 2021 at Regional Research Station, S. D. Agricultural University, Kothara (Gujarat). The treatments comprised of three levels of nitrogen (N1: 10 kg N/ha, N2: 20 kg N/ha and N3: 30 kg N/ha) and three levels of phosphorus (P1: 0, P2: 20, P3: 40 kg P2O5/ha) was laid out in a factorial randomized block design with three replications. Effect of different nitrogen levels on Marvel green forage yield was found significant in pooled analysis. Application of 30 kg nitrogen/ha (N3) recorded significantly the highest plant height (135.68 cm), effective tillers/tussock (47.44), green and dry forage yield @ 811.18 and 347.87 q/ha, Crude fibre content (38.36 %) and Crude protein content (5.21 %), while application of phosphorus has no impact significantly on yield of marvel grass in pooled as well as individual year of analysis
The Effects of Moisture Content on the Temperature of Some Selected Soil Samples in the Presence of Internal Heat
The effect of moisture content on the temperature of some selected soil samples in the presence of internal heat was studied. The governing equation was modeled using Bosenneque’s approximation base on some necessary assumptions by which the transfer occurred. These equations were non-dimensionalized by employing some standard dimensionless parameters and later reduced to ordinary differential equations using perturbation method. This was then solved analytically. The various effects of the physical parameters that materialized were examined on the unsaturated and saturated forms of some selected soil samples. With the aid of Matlab software, the numerical results were graphed for visual examination. It was observed that the presence of moisture content in these soils helped in boosting their temperatures as the solar radiation and internal heat increase
Allelopathic Potentiality of Euphorbia hypericifolia L. on Germination and Seedling Development of Sympatric Crops and Weeds
Euphorbia hypericifolia, a non-native herbaceous weedy plant was found to often form disproportionately dense, virtually monospecific stands in the Mount Bambouto Caldera, Cameroon. This observation is within the purview of allelopathy and is attributed to the release of botanicals by non native plants that harm naïve native flora, creating significant problems for agriculture and the environment. We investigated if the invasiveness of E. hypericifolia could be explained by its allelopathic potential at varying concentrations on five indicator plants. The results showed that the leaf, root and stem aqueous extracts of the plant exhibited significant inhibitory effects on the germination, radicle and plumule lengths of Biden pilosa, Amaranthus spinosus, Lactuca sativa, Zea mays and Lycopersicon esculentum at 100 % by 75.0, 69.4, 95.6, 28.0 and 97.2 %, respectively. The leaf extract was the most potent, while the stem extract was the least. The extract of E. hypericifolia was stimulatory (Lower concentrations) and inhibitory to the germination and growth of the test plants and its effect was concentration-dependent with the roots of target plants being more sensitive to the extracts than the plumule. L. esculentum was the most susceptible species to E. hypericifolia extracts while Z. mays was more tolerant than any of the tested plants. Results of total chlorophyll pigment accretion showed declining levels of chlorophyll detected in the leaves of tomato transplants cultivated in the augmented soils with rising dosage of the leaf residue of E. hypericifolia. B. pilosa planted on E. hypericifolia infested soil (EIS) showed very poor emergence recording only 7.5 % after 6 weeks as compared to 83.0 % in non E. hypericifolia infested soil (NIS). Qualitative phytochemical screening indicates E. hypericifolia is rich in secondary metabolites including alkaloids, glycosides, flavonoids, phenolics, tanins, Steriods and saponins. Acetone was the best extractant amongst the solvents used. This study has proven the allelopathic potential of E. hypericifolia and revealed some allelochemicals that may be exploited for the development of bioherbicides and plant growth promotion from natural products
The Potential of Cassava (Manihot esculenta Crantz) Peels as an Organic Fertilizer
Cassava peels are in large quantity and practically of no economic value in many developing nations such as Cameroon, where cassava is widely consumed and processed far beyond other crops. Cassava peels might be used in those countries to face declining soil fertility and soil erosion. This study aimed to evaluate the composting of cassava peels and the effect of the increasing quantity of cassava peels in the bin during the process of composting and to assess some physico-chemical qualities, biological properties and the phytotoxicity of the produced composts. After three months of composting the produced composts (C1; C2; C3 and C4) had a dark brown color, relatively dry, uniform structure and its texture were similar to the soil's texture. The electrical conductivity of the various composts was in between 1499 and 1924 µS.cm-1. The pH (6.50-6.73), was slightly acid, favorable for the cultivation of sweet pepper. The composts were rich in minerals (Mg2+; Ca2+; K+; and Na+) and poor in heavy metals such as (Cu, Zn and Mn). The composts C/N ratios were between 13.15 to 13.42. The produced composts showed a germination index and the rate of germination higher than 80% at all amounts, indicating the absence of phytotoxicity. The increased amounts of cassava peels did not alter the process of composting and increased the fungal and bacterial populations. In conclusion, cassava peels are good substrates that can be used to produce stable and inclusive organic fertilizers, with high nutrient content, and less hazardous material which could be used in farms to remediate declining soil fertility and to promote sustainable agriculture