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Evaluation Of the Antifungal Activity of Cassia fistula (Linn) On Phytopathogenic Fungi Isolated from Citrus sinensis
Get PDFCitrus sinensis is a prominent tropical fruit with nutritional and economic benefits for
humans. However, it can also be plagued by fungal diseases, causing global economic
and production reduction. The extensive application of synthetic fungicides in
agricultural systems has posed increased toxicological risks to humans and ecosystems.
However, the varying phytochemicals found in medicinal plants have enabled them to
be regarded as safe and effective alternatives. However, few studies have evaluated the
use of Cassia fistula extracts as potential bio-fungicides. This research purposed to
evaluate the antifungal activity of Cassia fistula leaflet extracts against phytopathogenic
fungi. Ethanol as well as aqueous extracts of Cassia fistula leaves were assessed for
antifungal activity. The agar well-diffusion technique was implemented for in
vitro screening, minimum inhibitory concentration (MIC) and minimum fungicidal
concentration (MFC) of all different extracts against isolated fungal species
of Aspergillus, Penicillium and Geotrichum. All fungal isolates identified from the spoiled
oranges were Aspergillus flavus, Aspergillus fumigatus, Geotrichum sp. and Fusarium sp.
Preliminary phytochemical screening exhibited the presence of carbohydrates,
terpenoids, quinones and saponins in both ethanolic and aqueous extracts. At 1000
mg/ml, the aqueous and ethanolic extracts had the highest antifungal activity against A.
flavus (40 mm) and Fusarium sp. (38 mm), respectively. Both extracts had no antifungal
activity against A. fumigatus at 62.5 mg/ml but zones of inhibition were observed from
the positive and negative controls of ketoconazole and DMSO, respectively. The
minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC)
were evaluated at 62.5 mg/ml and 250 mg/ml, respectively. This study's findings
demonstrated the antifungal potential of C. fistula leaf extracts as a bio-fungicidal agent
against fungal invasion in plant
Nanoparticles in Air and Their Impact on Air Quality
Get PDFThe chances of nanoparticles (NPs) being discharged into the environment
have escalated due to their extensive application in diverse fields and their
approximate annual global production range of 550–33,400 metric tons.
These nanoparticles, which are well known as biosafe materials, have gained
an abundant attention due to their versatility and ease of usage in a number of
industries, such as cosmetics, drugs, and agriculture. An ever-growing class
of airborne pollutants are metal-containing nanoparticles derived from both
natural and man-made sources. The increasing use of these particles has
resulted in growing number of complex deposits in the air we breathe. The
more of these particles we use, the more complicated the structures of the air
we breathe become. The atmosphere contains nanoparticles from a variety of
sources. Designed nanoparticles can leak into the atmosphere during
manufacture and application. Most of the time, combustion processes related
to energy generation, transportation by vehicles powered by gasoline or
diesel, and other industrial activities result in the production of nanoparticles in
urban settlements. Conversely, however, the nucleation and development of
new particles, or new particle production, is a significant source of
nanoparticles in rural areas. These compounds are released into the
environment due to the growing use of engineered nanoparticles in residential
and commercial settings. Awareness of these NPs’ mobility, reactivity,
ecotoxicity, and persistence is necessary to evaluate the harm they pose to
the environment
Construction of a Self-regulating Thermoelectric Air-Cooling System
Get PDFThe most common method of refrigeration, a vapor compression air cooling
system (VCACS), has adverse effects on both human health and the
environment, including refrigerant poisoning, ozone layer depletion, and other
severe consequences. This project attempts to provide an alternative method
of refrigeration that can compete with the VCACS and offer a more
sustainable solution. The thermoelectric air-cooling system (TACS) is one
such alternative, which operates without the use of gases. In this project, we
compare the TACS to the VCACS. The thermoelectric air cooler is
constructed using a Peltier module as the primary component, which is placed
on a heat pump to remove hot air and enable the device to reach optimal
temperatures. While the temperature of the thermoelectric cooler drops at
equal rate similar to that of a VCACS, it ceases moving after reaching a
specific temperature. During the experiment, it was observed that the TAC
can reach a mean temperature of 29.70 ℃ which is close to that of the VCAC
which is 29.35 ℃. It means the TAC has equal cooling rate just as the VCAC
(i.e., 0.053 ℃/min). Also, in terms of power consumption, compared to the
VCAC, the TAC consumes about 62.04 W of power which makes it more
energy efficient than the VCAC. Overall, the thermoelectric air cooler offers a
promising alternative to the traditional VCACS method of refrigeration, without
the negative influence on the environment and human health
DIGITAL TRANSFORMATION AND FINANCIAL PERFORMANCE: A STUDY OF LISTED MANUFACTURING COMPANIES IN NIGERIA
Get PDFThis study investigates the relationship between digital transformation and the financial performance of listed companies in the manufacturing industry in Nigeria from 2019 to 2023. The rapid pace of digital innovation has prompted many manufacturing firms to adopt new technologies; nonetheless, how these modifications affect financial performance remains under-explored. The purpose of this research is to bridge this gap by examining how digital transformation (IT infrastructure, digital payments, digital analytic tools, digital technology) influences key financial metrics—Debt to Equity Ratio (DER), Return on Equity (ROE), Return on Assets (ROA), and Net Assets per Share (NAPS). Using data from 33 listed manufacturing firms, this study employs the ordinary least squares (OLS) regression method to analyze periodic observations throughout the standard reporting period, which runs from January 1 to December 31. The results show significant positive relationships between digital transformation and ROA and ROE, suggesting that digital initiatives enhance operational efficiency and profitability. However, no significant impact was found on DER and NAPS, indicating that the benefits of digital transformation may not extend uniformly across all financial measures. The findings of the research have salient ramifications for Nigerian industrial firms. This positive correlation between digital transformation and profitability underscores the strategic importance of investing in digital technologies. Firms are encouraged to continue their digital transformation efforts to achieve improved financial performance. Policymakers and industry stakeholders should support these initiatives by providing a conducive environment for digital innovation
DUFFY ANTIGEN RECEPTOR FOR CHEMOKINES GENE POLYMORPHISMS AMONG NIGERIAN PROSTATE CANCER PATIENTS
Get PDFProstate cancer (PCa) accounts for roughly 1.4 million incidence cases and 357,000 deaths, remaining the most common solid tumour in men globally. Genetic variation including single nucleotide polymorphisms (SNPs) contributes to the geographic disparity in some cancers including PCa, observed among black men. The Duffy Antigen Receptor for Chemokines (DARC) or Atypical Chemokine Receptor 1 (ACKR1) gene is highly polymorphic, with different variations in the population. Studies have shown that DARC/ACKR1 gene polymorphism is associated with angiogenesis and tumor growth in some cancer types. No study has been carried out yet on this gene polymorphism in PCa. This study aims to identify genetic variations in the DARC/ACKR1 gene and their association with PCa risk. Genomic DNA obtained from the blood samples of consented 146 PCa patients and 146 age-matched healthy men were genotyped for rs12075, rs2814778, rs13962, rs3027012 and rs863002 SNPs in DARC/ACKR1 gene using TaqMan® SNP Genotyping Assays. Fisher exact test was used to analyze the association between the variables. P-value of < 0.05 was considered statistically significant and all statistical analysis was performed using R programming language. This study showed the presence of mutant alleles in rs12075, rs13962 and rs2814778 among our study population. There was no significant association observed between the polymorphisms and PCa (p-value = 0.975, OR (95%CI) =1 (0, 39.0)). Future research that will include a larger sample size is recommended to provide insight into the association between these SNPs and PCa susceptibility
SOCIOLOGICAL IMPACTS OF NAIRA REDESIGN ON THE PERFORMANCE OF SMALL BUSINESSES IN OGUN STATE.
Get PDFThis study examined sociological impacts of naira redesign on the performance of small businesses in Ogun state. The redesign of the Naira presented economic challenges for micro-businesses, many businesses suffered from depleted capital and financial hardship, and low sales resulted in low income affecting their family and well-being in the long run. This study focused on Ado-Odo LGA which helped in the geographical imbalance in the study of how naira redesign has affected MSMEs.
A descriptive research design was used in this study with the use of a questionnaire in the collection of data from owners of MSMEs in Ado Odo Ota LGA. Data was collected from 314 MSME owners across various communities in Ado-Odo Ota LGA, like Sango, Iju, Atan, and Ota. The Covenant University Research Ethics Committee (CUREC) in Nigeria has awarded ethical authorization, guaranteeing compliance with moral norms.
Micro, Small, and Medium Enterprises (MSMEs) in the Ado-Odo Ota Local Government Area revealed that the Naira redesign initiative had a negative impact on MSMEs, especially those with limited access to electronic payment methods. According to the research, it is recommended that MSMEs prioritize the development of digital literacy in order to maintain competitiveness in the digital age. Furthermore, it strongly advocates for the government to involve MSMEs in the development and implementation of policies.
In conclusion, the naira redesign policy, intended to move towards a cashless economy and enhance the currency's security, inadvertently exacerbated the challenges faced by MSMEs
Prospect o f Recovering Bio -fertilizer by Anaerobic Co - digesting Cow Manure, Palm Oil Sludge, and Cassava Peels
Get PDFImproper crop and animal waste management and disposal are now widely recognized as environmentally harmful practices. When crop waste is placed in landfills, greenhouse gases (GHG) like carbon dioxide (CO2) and methane (CH4) are created. In order to create the digestate for usage as bio-fertilizer from agricultural waste employing cow dung as an inoculum for 30 days of the hydraulic retention period, a 225L Polyethylene (PE) anaerobic digester was used in this study. Cassava peels, palm oil sludge, cow dung, and water were mixed in a 1:1:2:5.3 ratio. About 1.3 kilogram of crushed eggshells was added to keep the pH level within the range recommended for the anaerobic digestion process. In order to maintain mesophilic conditions during anaerobic co-digestion for enhanced organic fertilizer output, the greenhouse was used to regulate temperature. Since microbial populations flourish in friendly environments, the pH averaged 6.0 and the average slurry temperature was 34.76 oC during digestion. After 30 days of hydraulic retention time, a laboratory-scale elemental analysis of the digestate showed that the contents of nitrogen (N), phosphorus (P), and potassium (K) increased by 95%, 75%, and 93.8%, respectively. The anaerobic co-digestion of animal and agricultural waste has created digestate rich in NPK nutrients, but more research should be conducted to see whether the biofertilizer’s efficacy on fast-growing crops can be determined by measuring the number of harvests and height of the plants
Setting Time and Workability of Geopolymerized Fly Ash-Phosphogypsum Paste and Mortar
Get PDFGeopolymer is no longer viewed as a concept for a greener society but rather as a pragmatic solution for reducing CO2 emissions in the construction industry. It is commonly produced using industrial waste materials such as fly ash (FA) and phosphogypsum (PG). Globally, FA has an estimated annual production of around 1 billion tonnes and that of phosphogypsum is around 300 million tonnes, of which utilization stands at 50% and 15% of the total generated, respectively [1]. Geopolymers have been extensively studied as an alternative to ordinary Portland Cement (OPC) [2], [3] but to date, no study has been done to investigate the setting time and workability of geopolymerized fly ash-phosphogypsum paste and mortar.
This research investigates the setting time and workability of geopolymerized fly ash-phosphogypsum paste (GPP) and mortar (GPM) using a Vicat needle procedure per ASTM C191 and the flow table test per ASTM C1437, respectively. The materials used were PG, Class F FA, silica sand, NaOH pellets of 99% purity, and Na2SiO3 solution of the composition Na2O = 8.3%, SiO2 = 27.7%, H2O = 64%, and Ms (SiO2/Na2O) = 3.34. The dissolution of NaOH pellets in water is an exothermic process [4] therefore the prepared NaOH solution was kept in a sealed glass bottle for 24 hours at room temperature to allow sufficient cooling before mixing with the Na2SiO3 solution. The specimens were prepared at 10M NaOH + Na2SiO3 Ms of 3.34, Na2SiO3/ NaOH ratio of 1.5, Alkaline Liquid/Precursor ratio of 0.4, Binder/Aggregate ratio of 1.0, and varying PG at 10 wt% increments. As per ASTM C305 for mixing pastes and mortars, the preparation of the specimens started with dry mixing the FA with PG in a conventional pan mixer for 3 minutes, followed by the gradual addition of alkaline solution and wet mixing for 5 minutes. Soon after wet mixing, the manufactured paste and mortar were tested for setting time and workability.
It was found that an increase in the PG wt% led to a decrease and/or acceleration in the initial setting time (INSET) and final setting time (FINSET) attributed to the rapid dissolution of Ca2+ in low alkaline concentrations outnumbering that of Al3+ and Si4+ and thus forming ettringite and C-A-S-H gel that facilitates hardening shortening the setting time [5], [6]. The INSET of GPP decreased from 37 min (at 10wt% PG) to 27 min (at 30 wt% PG) while the FINSET of GPP decreased from 155 min (at 10wt% PG) to 125 min (at 30 wt% PG). The INSET of GPM decreased from 29 min (at 10wt% PG) to 23 min (at 30 wt% PG) while the FINSET of GPM decreased from 142 min (at 10wt% PG) to 113 min (at 30 wt% PG). Furthermore, the workability of GPP and GPM decreased with an increase in PG wt% attributed to faster hydration activity, accelerated setting, and increased viscosity. The workability of GPP decreased from 176 mm (at 10 wt% PG) to 138 mm (at 30 wt% PG) while that of GPM decreased from 137 mm (at 10 wt% PG) to 112 mm (at 30 wt% PG). The development of GPP and GPM offers a sustainable circularity construction solution to minimize OPC usage and prevent the disposal of FA and PG in landfills. Future research should investigate the mechanical properties of GPP and GPM
Geopolymer Production From Waste Polyethylene Terephthalate and Glass For Clay Subgrade Stabilization
Get PDFIn this study, the efficacy of Polyethylene Terephthalate (PET) and Waste Glass Powder (WGP) as soil
stabilizers was investigated to address the research questions and objectives. It examines the enhancement of
mechanical strength of clayey subgrade soils sourced from Ogun state, Nigeria across varying proportions
(5% −20%) including the potential cost analysis. Providing experimental insights into soil stabilization using
PET individually and in combination with WGP-based geopolymers. Optimal stabilization was achieved at 5%
PET, accompanied by 5%-20% WGP, and activated with a 2M NaOH solution. Results demonstrated enhanced
mechanical strength with both stabilizers, with the combination of PET and WGP proving the most effective.
Specifically, stabilization with 5% PET (1.18mm) WGP geopolymer, activated with 2% NaOH, yielded optimal
results, exhibiting UCS values ranging from 180kN/m2 to 320kN/m2, surpassing cement-based stabilization
(UCS value: 380kN/m2). Moreover, durability testing revealed significant improvements, with PET+WGP
samples displaying a UCS mean of 259.4kN/m2, a weight of 89.67g, and a percent change in mean and weight
of −25.79% and −25.86%, respectively, compared to cement-stabilized soil (UCS mean: 408.66 kN/m2,
percent change: 2.15%, weight mean: 109.25g, percent change: -25.86%). Furthermore, PET+WGP exhibited
a 125% increase in CBR compared to PET alone and a better cost reduction of $6,153,850,000.00 for 100km,
highlighting its superior performance and cost reduction. The findings of this study hold significance for
informed decision-making in material selection for road pavement works, offering an alternative method and
contributing to Sustainable Development Goals and Circular Economy initiatives by advocating sustainable
waste management and road infrastructure
AN AUTOMATED MALARIA DIAGNOSIS SYSTEM FOR DETECTING INFECTION SEVERITY FROM THICK BLOOD SMEAR IMAGES
Get PDFMalaria is a significant and life-threatening disease that poses a threat to global health and
the economy. Accurate diagnosis is crucial in combating this disease. Microscopy is
considered the gold standard for diagnosing malaria parasites and requires a skilled slide
reader to examine blood slides for the presence of parasites and careful quantification.
Therefore, automating the process would be beneficial. The accessibility and availability
of large curated datasets for quantifying malaria parasite images in thick blood smears
have posed a significant challenge. The absence of an accessible, fully automated, and
fully functional web-based system for multiclass classification is also a notable gap. This
study aims to develop an automated system for quantifying malaria parasites in routine
blood films. Blood samples collected from Covenant University Medical Centre and
AceMedicare clinic were used to generate a dataset of 1518 labeled thick blood smear
images. The annotations were recorded from the health facilities and used to correctly label
the images. The dataset includes 458 uninfected, 427 mild, and 633 severe thick blood
smear images. The images were digitized using the Olympus CX33 trinocular microscope.
Data processing techniques such as resizing, rescaling, and data augmentation were used
to prepare the dataset for training. Five transfer models - VGG16, VGG19, ResNet50,
InceptionV3, and DenseNet201 - were trained and evaluated on the newly generated
images. The models' accuracies were VGG16- 81.2%, VGG19- 82.5%, InceptionV3-
81.0%, DenseNet201- 81.8%, and ResNet- 68.3%. The best predictive model across all
performance metrics was VGG19 with an accuracy of 82.5%, precision of 82.0%, recall
of 82.0%, F1-score of 81.0%, and 0.38 loss. The best-performing predictive model was
deployed as a web-based application. The study proffers deep learning model capable of
classifying malaria thick blood smear images into multi class classification based on their
level of severity