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Showing papers by "Adama University published in 2022"


Journal ArticleDOI
TL;DR: In this paper, the gallic acid obtained from the ethanolic extract of Pomegranate(Punica granatum) pericarp, was successfully applied as a green and effective natural catalyst for the synthesis of novel quinoline based amino acid Schiff base ligand, L (C16H14N4O3) and its divalent metal complexes.

29 citations


Journal ArticleDOI
TL;DR: In this article, the authors evaluated the benefits and drawbacks of distinguishing sorption solar thermal cooling systems and showed that compared to other technologies, the solar absorption system is more efficient, so it is very commonly used for cooling applications in various locations.
Abstract: Conventional energy consumption in refrigeration is one of the important reasons in global warming. Solar cooling systems are becoming more compact, having lower costs, and are potential alternative technologies, especially in hot and sunny climates. The adsorption, absorption, and dissociative evaporative cooling (DEC) are the technologies used for sorption machines, which are discussed in this review paper. Various multi-criteria performance indicators appearing in the previous studies are discussed, followed by evaluating the benefits and drawbacks of distinguishing sorption solar thermal cooling systems. Market research is conducted to prove the capacity of these technologies. The review shows that compared to other technologies, the solar absorption system is more efficient, so it is very commonly used for cooling applications in various locations. An important topic was also presented using phase change materials and nanofluids in solar sorption systems, that need more research. It is noted from this that most solar cooling systems are hybrid in terms of source and there are multiple applications (cooling - heating and electricity generation). The software packages to study these systems are introduced. Further research is required on desiccant materials that can be regenerated under lower temperatures that would augment the extent of solar desiccant cooling application.

23 citations


DOI
01 Feb 2022
TL;DR: In this paper, the authors studied the reservoir quality of the Albian-Cenomanian reservoir of the Ivorian sedimentary basin, which consists mainly of conglomeratic, pebbly and very fine to coarse-grained sandstones.
Abstract: The Albian-Cenomanian reservoirs of the Ivorian sedimentary basin consist mainly of conglomeratic, pebbly, and very fine to coarse-grained sandstones. In the present study, the lithologic composition, flow and storage capacities, and reservoir quality parameters were studied in detail. Some fresh, clean and non-fractured samples were selected representative from FE-1 well in the depocenter of the basin, FE-2 well to the west, and FE-3 well to the east of the basin. Lithologic studies indicated that heterogeneity increases greatly to the east due to the implementation of diagenetic factors including cementation, silicification, authigenic clay minerals, and compaction. Though of the dominant reservoir quality-reducing factors, to the east, the reservoir quality increases due to increasing the grain size and the interstitial pore types. Porosity and permeability of samples were estimated by helium and nitrogen injection, respectively, whereas the reservoir quality was measured using different techniques, e.g., the FZI (flow zone indicator), the RQI (reservoir quality index), the effective pore radius (R35) of Winland, and the DRT (discrete rock type). The reservoir quality properties declared that the present plug samples can be clustered into six RRTs (reservoir rock types), with increasing reservoir quality from RRT6 (conglomeratic sandstone lithofacies) to RRT1 (deformed sandstone lithofacies).

20 citations



Journal ArticleDOI
TL;DR: In this paper , the removal of Pb2+ and Cd2+ using starch derivatives adsorbents (SDAs) has been studied for removing heavy metal ions from water.

8 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated the structural and hydrocarbon evolution of the Borno Basin to reassess its PSEs, hydrocarbon potential and migration trends, showing that the basin has extended up to 2900 km since the Late Cretaceous.

7 citations


Journal ArticleDOI
TL;DR: The Cr-doped ZnO photocatalysts were synthesized through the chromium ion accumulations by water hyacinth (Eichhornia crassipes) in the preparation process, the plant tissues were immersed in different sample flasks containing chromium precursors for 1, 2, 4, 6, and 8 days as discussed by the authors .
Abstract: The Cr-doped ZnO photocatalysts were synthesized through the chromium ion accumulations by water hyacinth (Eichhornia crassipes). In the preparation process, the plant tissues were immersed in different sample flasks containing chromium precursors for 1, 2, 4, 6, and 8 days. The plant tissue containing chromium ion was mixed with zinc precursor followed by calcinations. For simplicity, the prepared Cr-doped ZnO samples with the plant immersed for 1, 2, 4, 6, and 8 days were abbreviated as D1, D2, D4, D6, and D8, respectively. Moreover, pure ZnO was also prepared without the water hyacinth plant accumulated with chromium ion for comparison purposes. The powder sample characterizations were performed and evaluated in the degradation of methylene blue (MB). The Cr-doped ZnO sample (D1) degrades 80% of MB dye while the D2, D4, D6, D8, and pure ZnO samples degrade only 74, 76, 79, 73, and 25%, respectively. On the other hand, without the addition of catalysts (blank), there was no significant degradation of MB dye within 90 min irradiation. Therefore, the degradation performance of Cr-doped ZnO in the presence of optimum amount of chromium dopant and water hyacinth is highly improved than that of pure ZnO. The catalytic improvement may be as a result of reducing the photogenerated electron and hole recombination rates due to the presence of dopants. Moreover, the presence of the Eichhornia crassipes plant in the synthesis of Cr-doped ZnO could also prevent further aggregations and particle size growth and enhance the porosity after calcination.

7 citations


Journal ArticleDOI
TL;DR: In this paper, the authors focused on identifying the region suitable for agriculture-based, using new irrigation groundwater quality plot and its spatio-temporal variation with fuzzy logic technique in a geographic information system (GIS) platform.

6 citations


Journal ArticleDOI
TL;DR: In this article, the authors used 3D seismic and borehole data in the Broad Fourteens Basin, Southern North Sea, to investigate the relationship between lithology and fault throw distribution, as well as to understand the reactivation and growth histories of faults developed due to tectonic inversion.

3 citations


Journal ArticleDOI
milyanyyhj1
TL;DR: The special issue of Innovation and Development on "Building innovation capabilities for sustainable industrialization in Africa" as mentioned in this paper presents a series of articles on building local technological capabilities and their implications for formulating and implementing policies in Africa's industrialization agenda.
Abstract: The special issue of Innovation and Development on ‘Building innovation capabilities for sustainable industrialization in Africa … ’, presents a series of articles on building local technological capabilities and their implications for formulating and implementing policies in Africa’s industrialization agenda. Despite the high potential of Africa in advancing its industrialization mainly in resource-intensive sectors, progress remains low. Empirical evidence on the reasons for this problem is inadequate and patchy. Articles in this special issue address the gaps by delving into empirical issues ranging from sector-specific innovation capabilities to national systems of innovation. Based on first-hand data collected from South Africa, Ethiopia, Ghana, Nigeria, Kenya, and Rwanda, the articles unravelled key structural and systemic problems behind Africa’s dismal progress in developing technological and industrial capabilities. Together, these articles advance our understanding of how to improve the effectiveness of innovations, industrial policies, and coordination for inclusive and sustainable industrialization.

2 citations


Journal ArticleDOI
TL;DR: A comparison of the performance and cognitive workload between three UAV control interfaces on an nCA (navigation control autonomy) Tier 1-III flight navigation task was conducted and it was concluded that, although the mSVG was better than the standard RCJ interface, the AAP-assisted RCJ was found to be as effective as (in some cases better than) themSVG interface.

Journal ArticleDOI
Akey Sungheetha1
TL;DR: In this article , the authors proposed a framework to display real-time environmental data acquired by IoT agents in the interior environment, including air temperature, light intensity, and humidity, on the server platform and in the environment application.
Abstract: Recently, various indoor based sensors that were formerly separated from the digital world, are now intertwined with it. The data visualization may aid in the comprehension of large amounts of information. Building on current server-based models, this study intends to display real environmental data acquired by IoT agents in the interior environment. Sensors attached to Arduino microcontrollers are used to collect environmental data for the smart campus environment, including air temperature, light intensity, and humidity. This proposed framework uses the system's server and stores sensor readings, which are subsequently shown in real time on the server platform and in the environment application. However, most current IoT installations do not make use of the enhanced digital representations of the server and its graphical display capabilities in order to improve interior safety and comfort conditions. The storage of such real-time data in a standard and organized way is still being examined even though sensor data integration with storing capacity server-based models has been studied in academics.



Journal ArticleDOI
Giulio Camisani1
31 Dec 2022
TL;DR: In this paper , an analysis of noise robustness of Cochleogram and Mel Spectrogram features in speaker recognition using deep learning model is conducted at the Signal to Noise Ratio (SNR) level from −5 dB to 20 dB.
Abstract: The performance of speaker recognition systems is very well on the datasets without noise and mismatch. However, the performance gets degraded with the environmental noises, channel variation, physical and behavioral changes in speaker. The types of Speaker related feature play crucial role in improving the performance of speaker recognition systems. Gammatone Frequency Cepstral Coefficient (GFCC) features has been widely used to develop robust speaker recognition systems with the conventional machine learning, it achieved better performance compared to Mel Frequency Cepstral Coefficient (MFCC) features in the noisy condition. Recently, deep learning models showed better performance in the speaker recognition compared to conventional machine learning. Most of the previous deep learning-based speaker recognition models has used Mel Spectrogram and similar inputs rather than a handcrafted features like MFCC and GFCC features. However, the performance of the Mel Spectrogram features gets degraded in the high noise ratio and mismatch in the utterances. Similar to Mel Spectrogram, Cochleogram is another important feature for deep learning speaker recognition models. Like GFCC features, Cochleogram represents utterances in Equal Rectangular Band (ERB) scale which is important in noisy condition. However, none of the studies have conducted analysis for noise robustness of Cochleogram and Mel Spectrogram in speaker recognition. In addition, only limited studies have used Cochleogram to develop speech-based models in noisy and mismatch condition using deep learning. In this study, analysis of noise robustness of Cochleogram and Mel Spectrogram features in speaker recognition using deep learning model is conducted at the Signal to Noise Ratio (SNR) level from −5 dB to 20 dB. Experiments are conducted on the VoxCeleb1 and Noise added VoxCeleb1 dataset by using basic 2DCNN, ResNet-50, VGG-16, ECAPA-TDNN and TitaNet Models architectures. The Speaker identification and verification performance of both Cochleogram and Mel Spectrogram is evaluated. The results show that Cochleogram have better performance than Mel Spectrogram in both speaker identification and verification at the noisy and mismatch condition.



Journal ArticleDOI
Mesfin Abebe1
TL;DR: In this paper , the authors used binary logistic regression to identify the associated factors of low birth weight (LBW) and found that history of chronic medical illness, haemoglobin level, iron/folic acid supplementation and extra meal during pregnancy were associated with LBW.
Abstract: Only 14% of births had information on birth weight available at the time of birth in Ethiopia. Hence, previous studies underestimate the magnitude and associated factors of low birth weight (LBW). As a result, the goal of this study is to fill those gaps in the previous studies. An institution-based cross-sectional study was employed. Binary logistic regression was used to identify the associated factors. In this study, the magnitude of LBW was 13.06%. History of chronic medical illness (AOR = 3; 95% CI: (1.02, 9.17)), haemoglobin level during pregnancy (AOR = 0.23; 95% CI: (0.10, 0.50)), iron/folic acid supplementation (AOR = 0.27; 95% CI: (0.10, 0.72)) and extra meal during pregnancy (AOR = 3.2; 95% CI: (1.52, 7.00)) were significantly associated with LBW. The magnitude of LBW in this study was comparable to the Ethiopian Demographic and Health Survey (EDHS) report from 2016. It is better to intervene in those identified factors in order to reduce LBW.Impact StatementWhat is already knownon this subject? Low birth weight (LBW) accounts for 60-80% of all neonatal deaths each year. In developing countries like Ethiopia, LBW is a major public health concern. Almost half of the world's infants are not weighed at birth, a figure that is especially high in sub-Saharan Africa including Ethiopia.What dothe resultsof this study add? Only 14% of births had information on birth weight available at the time of birth in Ethiopia. Hence, previous studies underestimate the magnitude and associated factors of LBW. To meet the Sustainable Development Goals (SDGs)-2030 targets for neonatal and child mortality, sufficient evidence on the magnitude of LBW and associated factors must be important in order to contribute to the development of timely interventions. A history of chronic medical illness, haemoglobin level, iron/folic acid supplementation and extra meal during pregnancy was associated with LBW.What are the implications of these findings for clinical practice and/or further research? The findings of this study will be useful in developing better health policies to prevent LBW as well as interventions that can target the identified factors.




Posted ContentDOI
Kero Jemal1
12 Oct 2022
TL;DR: In this paper , a successful callus induction protocol from leaf and nodal explants of A. serratus using MS media supplemented with different concentrations and combinations of plant growth regulators (2,4-D, NAA, and BAP).
Abstract: Abstract Background Allophylus serratus Roxb (Kurz.) is a medicinal plant with various therapeutic properties. It has been used for the treatment of various alignments such as elephantiasis, edema, fractured bones, in bone dislocations, wound, several gastrointestinal disorders such as dyspepsia, anorexia, and diarrhea. The aim of this study is to establish protocol for surface sterilization, in vitro callus induction and plant regeneration from leaf and nodal segment explants of Allophylus serratus. Results From the tested media, the maximum callus induction frequency (81.11%) from leaf and 84.44% from nodal segment explants were achieved on MS medium supplemented with 3 mg l − 1 BAP) combined with 0.5mgl − 1 NAA. The highest shoot regeneration frequency (57.78%) and root regeneration frequency (65.55%) were achieved on growth regulators free MS medium and MS medium supplemented with 1.5 mg l − 1 IBA respectively. Acclimatization of the regenerated plantlets was established successfully (100%) in a pot containing sand, soil and compost in 1:2:2 ratios. Conclusions In this study successful callus induction protocol from leaf and nodal explants of A. serratus using MS media supplemented with different concentrations and combinations of plant growth regulators (2,4-D, NAA, and BAP). MS media containing 3mg/l BAP and 0.5mg/l NAA was the most efficient for callus induction. these callus induction and plant regeneration protocols are very important for mass propagation of the species and also opens a new way to facilitate secondary metabolites production and isolation of pharmaceuticals from callus rather than harvesting the plant.

Journal ArticleDOI
Regina Fritz1
TL;DR: A 75 years old male farmer presented with worsening of difficulty of passing feces and flatus and intermittent abdominal distention of 3 months. Physical examination led to diagnosis of severe anal stenosis as discussed by the authors .

Posted ContentDOI
22 Aug 2022
TL;DR: In this paper , a nonlinear deterministic mathematical model for the impact of temperature and rainfall variability on coffee berry borer (Hypothenemus hampei) is presented.
Abstract: This study focuses on a nonlinear deterministic mathematical model for the impact of temperature and rainfall variability on coffee berry borer \emph{(Hypothenemus hampei)}. In the model analysis, CBB free and coexistence equilibria are computed. The basic reproduction numbers at a minimum and maximum temperature and rainfall are derived. The qualitative analysis of the model revealed the scenario for equilibria together with basic reproduction numbers. The local stability of equilibria is established through the Jacobian matrix and the Routh Hurwitz-criteria, while the global stability of equilibria is demonstrated using an appropriate Lyapunov function. The normalized sensitivity analysis has also been performed to observe the impact of different parameters on basic reproduction numbers. The proposed model is extended into an optimal control problem by incorporating two control variables, namely, the preventive measure variable based on the separation of susceptible coffee berries from contacting the pests based on biological control and an increase in the death rate of colonising females of CBB based on chemical control. Optimal disease control analysis is examined using Pontryagin’s minimum principle. Finally, the numerical simulations are performed based on analytical results and are discussed quantitatively. Furthermore, the cost-effectiveness of control strategies to determine the best approach to minimize the CBB burden was studied. The finding of this study shows that the use of chemical pesticides is very effective to combat pests with minimum costs.


Book ChapterDOI
Jafer Siraj1
02 Nov 2022
TL;DR: In this article , the authors reviewed the history and development of ethnobotany and the involvement of this branch of science in the innovation and derivation of drug products which is originated from plants and claimed by the traditional healers and indigenous people used for the prevention and treatment of disease.
Abstract: Ethnobotany is a life science which studies the interaction between human beings and flora in particular and broadly deals with the investigations, observations, and identifications of botanical diversity used for the prevention and treatment of human and livestock ailments. The current chapter reviews the history and development of ethnobotany and the involvement of this branch of science in the innovation and derivation of drug products which is originated from plants and claimed by the traditional healers and indigenous people used for the prevention and treatment of disease. This chapter also combines interdisciplinary and multidisciplinary methods that can lead to further productive, comprehensive, and systemic guesstimates in the investigation of the relationship between the plants and humans. Regardless of its various bottlenecks, ethnobotany becomes an attractive and hopeful area of research. It also covers ethnobotanical knowledge and modern science, ethnobotany research and their applications, plant conservation and sustainable management practices, taxonomy, and economic botany. The chapter also deals with the ways in which different societies and cultures have come to perceive, know, use, classify, and symbolically represent plants and animals.