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1.
Environ Res ; 249: 118320, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331148

RESUMO

In a global context, trace element pollution assessment in complex multi-aquifer groundwater systems is important, considering the growing concerns about water resource quality and sustainability worldwide. This research addresses multiple objectives by integrating spatial, chemometric, and indexical study approaches, for assessing trace element pollution in the multi-aquifer groundwater system of the Al-Hassa Oasis, Saudi Arabia. Groundwater sampling and analysis followed standard methods. For this purpose, the research employed internationally recognized protocols for groundwater sampling and analysis, including standardized techniques outlined by regulatory bodies such as the United States Environmental Protection Agency (USEPA) and the World Health Organization (WHO). Average values revealed that Cr (0.041) and Fe (2.312) concentrations surpassed the recommended limits for drinking water quality, posing serious threats to groundwater usability by humans. The trace elemental concentrations were ranked as: Li < Mn < Co < As < Mo < Zn < Al < Ba < Se < V < Ni < Cr < Cu < B < Fe < Sr. Various metal(loid) pollution indices, including degree of contamination, heavy metal evaluation index, heavy metal pollution index, and modified heavy metal index, indicated low levels of groundwater pollution. Similarly, low values of water pollution index and weighted arithmetic water quality index were observed for all groundwater points, signifying excellent groundwater quality for drinking and domestic purposes. Spatial distribution analysis showed diverse groundwater quality across the study area, with the eastern and western parts displaying a less desirable quality, while the northern has the best, making water users in the former more vulnerable to potential pollution effects. Thus, the zonation maps hinted the necessity for groundwater quality enhancement from the western to the northern parts. Chemometric analysis identified both human activities and geogenic factors as contributors to groundwater pollution, with human activities found to have more significant impacts. This research provides the scientific basis and insights for protecting the groundwater system and ensuring efficient water management.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Oligoelementos , Poluentes Químicos da Água , Água Subterrânea/análise , Água Subterrânea/química , Arábia Saudita , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Oligoelementos/análise
2.
Molecules ; 28(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37049937

RESUMO

The degradation of groundwater (GW) quality due to seawater intrusion (SWI) is a major water security issue in water-scarce regions. This study aims to delineate the impact of SWI on the GW quality of a multilayered aquifer system in the eastern coastal region of Saudi Arabia. The physical and chemical properties of the GW were determined via field investigations and laboratory analyses. Irrigation indices (electrical conductivity (EC), potential salinity (PS), sodium adsorption ratio (SAR), Na%, Kelly's ratio (KR), magnesium adsorption ratio (MAR), and permeability index (PI)) and a SWI index (fsea) were obtained to assess the suitability of GW for irrigation. K-mean clustering, correlation analysis, and principal component analysis (PCA) were used to determine the relationship between irrigation hazard indices and the degree of SWI. The tested GW samples were grouped into four clusters (C1, C2, C3, and C4), with average SWI degrees of 15%, 8%, 5%, and 2%, respectively. The results showed that the tested GW was unsuitable for irrigation due to salinity hazards. However, a noticeable increase in sodium and magnesium hazards was also observed. Moreover, increasing the degree of SWI (fsea) was associated with increasing salinity, sodium, and magnesium, with higher values observed in the GW samples in cluster C1, followed by clusters C2, C3, and C4. The correlation analysis and PCA results illustrated that the irrigation indices, including EC, PS, SAR, and MAR, were grouped with the SWI index (fsea), indicating the possibility of using them as primary irrigation indices to reflect the impact of SWI on GW quality in coastal regions. The results of this study will help guide decision-makers toward proper management practices for SWI mitigation and enhancing GW quality for irrigation.

3.
J Environ Manage ; 316: 115316, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35598454

RESUMO

It is difficult to predict and model with an accurate model the floods, that are one of the most destructive risks across the earth's surface. The main objective of this research is to show the prediction power of three ensemble algorithms with respect to flood susceptibility estimation. These algorithms are: Iterative Classifier Optimizer - Alternating Decision Tree - Frequency Ratio (ICO-ADT-FR), Iterative Classifier Optimizer - Deep Learning Neural Network - Frequency Ratio (ICO-DLNN-FR) and Iterative Classifier Optimizer - Multilayer Perceptron - Frequency Ratio (ICO-MLP-FR). The first stage of the manuscript consisted of the collection and processing of the geodatabase needed in the present study. The geodatabase comprises a number of 14 flood predictors and 132 known flood locations. The Correlation-based Feature Selection (CFS) method was used in order to assess the prediction capacity of the 14 predictors in terms of flood susceptibility estimation. The training and validation of the three ensemble models constitute the next stage of the scientific workflow. Several statistical metrics and ROC curve method were involved in the evaluation of the model's performance and accuracy. According to ROC curves all the models achieved high performances since their AUC had values above 0.89. ICO-DLNN-FR proved to be the most accurate model (AUC = 0.959). The outcomes of the study can be used to guide future flood risk management and sustainable land-use planning in the designated area.


Assuntos
Aprendizado Profundo , Inundações , Algoritmos , Sistemas de Informação Geográfica , Redes Neurais de Computação
4.
Molecules ; 27(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36296433

RESUMO

Seawater intrusion (SWI) is the main threat to fresh groundwater (GW) resources in coastal regions worldwide. Early identification and delineation of such threats can help decision-makers plan for suitable management measures to protect water resources for coastal communities. This study assesses seawater intrusion (SWI) and GW salinization of the shallow and deep coastal aquifers in the Al-Qatif area, in the eastern region of Saudi Arabia. Field hydrogeological and hydrochemical investigations coupled with laboratory-based hydrochemical and isotopic analyses (18O and 2H) were used in this integrated study. Hydrochemical facies diagrams, ionic ratio diagrams, and spatial distribution maps of GW physical and chemical parameters (EC, TDS, Cl-, Br-), and seawater fraction (fsw) were generated to depict the lateral extent of SWI. Hydrochemical facies diagrams were mainly used for GW salinization source identification. The results show that the shallow GW is of brackish and saline types with EC, TDS, Cl-, Br- concentration, and an increasing fsw trend seaward, indicating more influence of SWI on shallow GW wells located close to the shoreline. On the contrary, deep GW shows low fsw and EC, TDS, Cl-, and Br-, indicating less influence of SWI on GW chemistry. Moreover, the shallow GW is enriched in 18O and 2H isotopes compared with the deep GW, which reveals mixing with recent water. In conclusion, the reduction in GW abstraction in the central part of the study area raised the average GW level by three meters. Therefore, to protect the deep GW from SWI and salinity pollution, it is recommended to implement such management practices in the entire region. In addition, continuous monitoring of deep GW is recommended to provide decision-makers with sufficient data to plan for the protection of coastal freshwater resources.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental/métodos , Fácies , Água Subterrânea/análise , Isótopos/análise , Salinidade , Arábia Saudita , Água do Mar/análise , Água/análise , Poluentes Químicos da Água/análise
5.
Molecules ; 27(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35807465

RESUMO

Unconsolidated earthen surface materials can retain heavy metals originating from different sources. These metals are dangerous to humans as well as the immediate environment. This danger leads to the need to assess various geochemical conditions of the materials. In this study, the assessment of topsoil materials' contamination with heavy metals (HMs) was conducted. The material's representative spatial samples were taken from various sources: agricultural, industrial, and residential areas. The materials include topsoil, eolian deposits, and other unconsolidated earthen materials. The samples were analyzed using the ICP-OES. The obtained results based on the experimental procedure indicated that the average levels of the heavy metals were: As (1.21 ± 0.69 mg/kg), Ba (110.62 ± 262 mg/kg), Hg (0.08 ± 0.18 mg/kg), Pb (6.34 ± 14.55 mg/kg), Ni (8.95 ± 5.66 mg/kg), V (9.98 ± 6.08 mg/kg), Cd (1.18 ± 4.33 mg/kg), Cr (31.79 ± 37.9 mg/kg), Cu (6.76 ± 12.54 mg/kg), and Zn (23.44 ± 84.43 mg/kg). Subsequently, chemometrics modeling and a prediction of Cr concentration (mg/kg) were performed using three different modeling techniques, including two artificial intelligence (AI) techniques, namely, generalized neural network (GRNN) and Elman neural network (Elm NN) models, as well as a classical multivariate statistical technique (MST). The results indicated that the AI-based models have a superior ability in estimating the Cr concentration (mg/kg) than MST, whereby GRNN can enhance the performance of MST up to 94.6% in the validation step. The concentration levels of most metals were found to be within the acceptable range. The findings indicate that AI-based models are cost-effective and efficient tools for trace metal estimations from soil.


Assuntos
Metais Pesados , Poluentes do Solo , Solo , Inteligência Artificial , Quimiometria , Cromo/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Modelos Químicos , Análise Multivariada , Redes Neurais de Computação , Arábia Saudita , Solo/química , Poluentes do Solo/análise
6.
BMC Public Health ; 20(1): 938, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539691

RESUMO

BACKGROUND: Measles is a vaccine preventable, highly transmissible viral infection that affects mostly children under five years. It has been ear marked for elimination and Nigeria adopted the measles elimination strategies of the World Health Organization (WHO) African region to reduce cases and deaths. This study was done to determine trends in measles cases in Bayelsa state, to describe cases in terms of person and place, identify gaps in the case-based surveillance data collection system and identify risk factors for measles infection. METHODS: We carried out a secondary data analysis of measles case-based surveillance data for the period of January 2014 to December 2018 obtained in Microsoft Excel from the State Ministry of Health. Cases were defined according to WHO standard case definitions. We calculated frequencies, proportions, estimated odds ratios (OR), 95% confidence intervals (CI) and multivariate analysis. RESULTS: A total of 449 cases of measles were reported. There were 245(54.6%) males and the most affected age group was 1-4 years with 288(64.1%) cases. Of all cases, 289(9.35%) were confirmed and 70 (48.27%) had received at least one dose of measles vaccine. There was an all-year transmission with increased cases in the 4th quarter of the year. Yenegoa local government area had the highest number of cases. Timeliness of specimen reaching the laboratory and the proportion of specimens received at the laboratory with results sent to the national level timely were below WHO recommended 80% respectively. Predictors of measles infection were, age less than 5 years (AOR: 0.57, 95% CI: 0.36-0.91) and residing in an urban area (AOR: 1.55, 95% CI:1.02-2.34). CONCLUSIONS: Measles infection occurred all-year round, with children less than 5 years being more affected. Measles case-based surveillance system showed high levels of case investigation with poor data quality and poor but improving indicators. Being less than 5 years was protective of measles while living in urban areas increased risk for infection. We recommended to the state government to prioritize immunization activities in the urban centers, start campaigns by the 4th quarter and continue to support measles surveillance activities and the federal government to strengthen regional laboratory capacities.


Assuntos
Atenção à Saúde/tendências , Vacina contra Sarampo/administração & dosagem , Sarampo/prevenção & controle , Vigilância da População/métodos , Indicadores de Qualidade em Assistência à Saúde/tendências , Vacinação/estatística & dados numéricos , Vacinação/tendências , Adolescente , Criança , Pré-Escolar , Atenção à Saúde/estatística & dados numéricos , Feminino , Previsões , Humanos , Incidência , Lactente , Masculino , Nigéria/epidemiologia , Prevalência , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Fatores de Risco , Organização Mundial da Saúde
7.
Water Sci Technol ; 78(10): 2064-2076, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30629534

RESUMO

In the present study, three different artificial intelligence based non-linear models, i.e. feed forward neural network (FFNN), adaptive neuro fuzzy inference system (ANFIS), support vector machine (SVM) approaches and a classical multi-linear regression (MLR) method were applied for predicting the performance of Nicosia wastewater treatment plant (NWWTP), in terms of effluent biological oxygen demand (BODeff), chemical oxygen demand (CODeff) and total nitrogen (TNeff). The daily data were used to develop single and ensemble models to improve the prediction ability of the methods. The obtained results of single models proved that, ANFIS model provides effective outcomes in comparison with single models. In the ensemble modeling, simple averaging ensemble, weighted averaging ensemble and neural network ensemble techniques were proposed subsequently to improve the performance of the single models. The results showed that in prediction of BODeff, the ensemble models of simple averaging ensemble (SAE), weighted averaging ensemble (WAE) and neural network ensemble (NNE), increased the performance efficiency of artificial intelligence (AI) modeling up to 14%, 20% and 24% at verification phase, respectively, and less than or equal to 5% for both CODeff and TNeff in calibration phase. This shows that NNE model is more robust and reliable ensemble method for predicting the NWWTP performance due to its non-linear averaging kernel.


Assuntos
Inteligência Artificial , Eliminação de Resíduos Líquidos/métodos , Lógica Fuzzy , Modelos Lineares , Redes Neurais de Computação , Águas Residuárias
8.
Appl Environ Microbiol ; 81(7): 2591-602, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25636844

RESUMO

To highlight different transcriptional behaviors of the phytoplasma in the plant and animal host, expression of 14 genes of "Candidatus Phytoplasma asteris," chrysanthemum yellows strain, was investigated at different times following the infection of a plant host (Arabidopsis thaliana) and two insect vector species (Macrosteles quadripunctulatus and Euscelidius variegatus). Target genes were selected among those encoding antigenic membrane proteins, membrane transporters, secreted proteins, and general enzymes. Transcripts were detected for all analyzed genes in the three hosts; in particular, those encoding the antigenic membrane protein Amp, elements of the mechanosensitive channel, and two of the four secreted proteins (SAP54 and TENGU) were highly accumulated, suggesting that they play important roles in phytoplasma physiology during the infection cycle. Most transcripts were present at higher abundance in the plant host than in the insect hosts. Generally, transcript levels of the selected genes decreased significantly during infection of A. thaliana and M. quadripunctulatus but were more constant in E. variegatus. Such decreases may be explained by the fact that only a fraction of the phytoplasma population was transcribing, while the remaining part was aging to a stationary phase. This strategy might improve long-term survival, thereby increasing the likelihood that the pathogen may be acquired by a vector and/or inoculated to a healthy plant.


Assuntos
Arabidopsis/microbiologia , Perfilação da Expressão Gênica , Hemípteros/microbiologia , Interações Hospedeiro-Patógeno , Phytoplasma/crescimento & desenvolvimento , Phytoplasma/genética , Animais , Dados de Sequência Molecular , Análise de Sequência de DNA , Fatores de Tempo
9.
Fungal Genet Biol ; 71: 1-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25128845

RESUMO

Mycorrhizal fungi are key mediators of soil-to-plant movement of mineral nutrients, including essential and non-essential metals. In soil conditions that facilitate mobilization of metal ions, potentially toxic metals can interfere with nitrogen metabolism in both plants and microorganisms. Less is known about possible relationships between nitrogen metabolism and responses to heavy metals. Aim of this study was to investigate this aspect in the ericoid mycorrhizal fungus Oidiodendron maius strain Zn, a metal tolerant ascomycete. Growth of O. maius Zn on zinc and cadmium containing media was significantly affected by the nitrogen source. Screening of a library of O. maius Zn random genetic transformants for sensitivity to heavy metals (zinc and cadmium) and oxidative stress (menadione) yielded a mutant strain that carried a partial deletion of the glutamate synthase (NADH-GOGAT EC 1.4.1.14) gene and its adjacent gene, the APC15 subunit of the anaphase promoting complex. Comparison of WT and OmGOGAT-OmAPC15 mutant strains indicated an impaired N-metabolism and altered stress tolerance, and assays on the OmAPC15-recomplemented strains ascribed the observed phenotypes to the deletion in the OmGOGAT gene. OmGOGAT disruption modified the nitrogen pathway, with a strong reduction of the associated glutamine synthetase (GS, EC 6.3.1.2) activity and an up-regulation of the alternative NADP-glutamate dehydrogenase (NADP-GDH, EC 1.4.1.4) pathway for glutamate biosynthesis. Unless they were supplemented with glutamine, O. maius Zn transformants lacking OmGOGAT were very sensitive to zinc. These results highlight the importance of nitrogen metabolism not only for nitrogen assimilation and transformation, but also for stress tolerance. For mycorrhizal fungi, such as O. maius, this may bear consequences not only to the fungus, but also to the host plant.


Assuntos
Ciclossomo-Complexo Promotor de Anáfase/genética , Ascomicetos/genética , Glutamato Sintase/genética , Micorrizas/genética , Nitrogênio/metabolismo , Zinco/metabolismo , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Cádmio/metabolismo , Deleção de Genes , Desidrogenase de Glutamato (NADP+)/metabolismo , Glutamato Sintase/metabolismo , Glutamato-Amônia Ligase/metabolismo , Redes e Vias Metabólicas , Micorrizas/crescimento & desenvolvimento , Micorrizas/metabolismo , Estresse Oxidativo , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Transformação Genética , Vaccinium myrtillus/microbiologia
10.
Nucleic Acids Res ; 39(17): 7548-63, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21672957

RESUMO

Cadmium is a genotoxic pollutant known to target proteins that are involved in DNA repair and in antioxidant defence, altering their functions and ultimately causing mutagenic and carcinogenic effects. We have identified a PLAC8 domain-containing protein, named OmFCR, by a yeast functional screen aimed at identifying genes involved in cadmium resistance in the endomycorrhizal fungus Oidiodendron maius. OmFCR shows a remarkable specificity in mediating cadmium resistance. Both its function and its nuclear localization in yeast strictly depend on the interaction with Mlh3p, a subunit of the mismatch repair (MMR) system. Although proteins belonging to the PLAC8 family are widespread in eukaryotes, they are poorly characterized and their biological role still remains elusive. Our work represents the first report about the potential role of a PLAC8 protein in physically coupling DNA lesion recognition by the MMR system to appropriate effectors that affect cell cycle checkpoint pathways. On the basis of cell survival assays and yeast growth curves, we hypothesize that, upon cadmium exposure, OmFCR might promote a higher rate of cell division as compared to control cells.


Assuntos
Ascomicetos/genética , Cádmio/toxicidade , Proteínas Fúngicas/metabolismo , Mutagênicos/toxicidade , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Ascomicetos/metabolismo , Proteínas de Ciclo Celular/genética , Biologia Computacional/métodos , Reparo de Erro de Pareamento de DNA , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Genes Fúngicos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Alinhamento de Sequência , Fatores de Transcrição/genética , Técnicas do Sistema de Duplo-Híbrido
11.
Rev Med Interne ; 44(12): 641-645, 2023 Dec.
Artigo em Francês | MEDLINE | ID: mdl-37827928

RESUMO

INTRODUCTION: Pretibial myxedema is a rare manifestation of Graves' disease, and pseudotumoral forms may be confused with lower limb lymphedema. OBSERVATIONS: We reported 3 cases of pretibial myxedema in 2 women and 1 man, aged 72, 66, and 49 years, treated for Graves' disease 3, 25 and 32 years previously. Two patients were active smokers. Lymphedema diagnosis of the lower limbs was suspected in the presence of bilateral pseudotumoral lesions of the feet, toes and ankles and the presence of a Stemmer's sign (skin thickening at the base of the 2nd toe, pathognomonic of lymphedema). Lymphoscintigraphy in one case was normal, not confirming lymphedema. CONCLUSION: Pretibial pseudotumoral myxedema is a differential diagnosis of lower limb lymphedema. This diagnosis is confirmed by questioning the patient about preexisting Graves' disease, the underlying etiology, to decide the appropriate treatment and to encourage cessation of smoking, which is a risk factor for pretibial myxedema.


Assuntos
Doença de Graves , Dermatoses da Perna , Mixedema , Masculino , Humanos , Feminino , Mixedema/diagnóstico , Mixedema/etiologia , Mixedema/patologia , Diagnóstico Diferencial , Doença de Graves/complicações , Doença de Graves/diagnóstico , Extremidade Inferior/patologia , Dedos do Pé/patologia , Dermatoses da Perna/diagnóstico , Dermatoses da Perna/etiologia , Dermatoses da Perna/patologia
12.
Heliyon ; 9(4): e15483, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37128320

RESUMO

Human health and the sustainability of the socioeconomic system are directly related to water quality. As anthropogenic activity becomes more intense, pollutants, particularly potentially harmful elements (PHEs), penetrate water systems and degrade water quality. The purpose of this study was to evaluate the safety of using groundwater for domestic and drinking purposes through oral and dermal exposure routes, as well as the potential health risks posed to humans in the Nnewi and Awka regions of Nigeria. The research involved the application of a combination of the National Sanitation Foundation Water Quality Index (NSFWQI), HERisk code, and hierarchical dendrograms. Additionally, we utilized the regulatory guidelines established by the World Health Organization and the Standard Organization of Nigeria to compare the elemental compositions of the samples. The physicochemical parameters and NSFWQI evaluation revealed that the majority of the samples were PHE-polluted. Based on the HERisk code, it was discovered that in both the Nnewi and Awka regions, risk levels are higher for people aged 1 to <11 and >65 than for people aged 16 to <65. Overall, it was shown that all age categories appeared to be more vulnerable to risks due to the consumption than absorption of PHEs, with Cd > Pb > Cu > Fe for Nnewi and Pb > Cd > Cu > Fe for water samples from Awka. Summarily, groups of middle age are less susceptible to possible health issues than children and elderly individuals. Hierarchical dendrograms and correlation analysis showed the spatio-temporal implications of the drinking groundwater quality and human health risks in the area. This research could help local government agencies make informed decisions on how to effectively safeguard the groundwater environment while also utilizing the groundwater resources sustainably.

13.
Life (Basel) ; 13(3)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36983868

RESUMO

Antiretroviral therapy (ART) is the common hope for HIV/AIDS-treated patients. Total commitments from individuals and the entire community are the major challenges faced during treatment. This study investigated the progress of ART in the Federal Teaching Hospital in Gombe state, Nigeria by using various records of patients receiving treatment in the ART hospital unit. We combined artificial intelligence (AI)-based models and correspondence analysis (CA) techniques to predict and visualize the progress of ART from the beginning to the end. The AI models employed are artificial neural networks (ANNs), adaptive neuro-fuzzy inference systems (ANFISs) and support-vector machines (SVMs) and a classical linear regression model of multiple linear regression (MLR). According to the outcome of this study, ANFIS in both training and testing outperformed the remaining models given the R2 (0.903 and 0.904) and MSE (7.961 and 3.751) values, revealing that any increase in the number of years of taking ART medication will provide HIV/AIDS-treated patients with safer and elongated lives. The contingency results for the CA and the chi-square test did an excellent job of capturing and visualizing the patients on medication, which gave similar results in return, revealing there is a significant association between ART drugs and the age group, while the association between ART drugs and marital status (93.7%) explained a higher percentage of variation compared with the remaining variables.

14.
ACS Omega ; 8(43): 40517-40531, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929092

RESUMO

The prediction of the yields of light olefins in the direct conversion of crude oil to chemicals requires the development of a robust model that represents the crude-to-chemical conversion processes. This study utilizes artificial intelligence (AI) and machine learning algorithms to develop single and ensemble learning models that predict the yields of ethylene and propylene. Four single-model AI techniques and four ensemble paradigms were developed using experimental data derived from the catalytic cracking experiments of various crude oil fractions in the advanced catalyst evaluation reactor unit. The temperature, feed type, feed conversion, total gas, dry gas, and coke were used as independent variables. Correlation matrix analyses were conducted to filter the input combinations into three different classes (M1, M2, and M3) based on the relationship between dependent and independent variables, and three performance metrics comprising the coefficient of determination (R2), Pearson correlation coefficient (PCC), and mean square error (MSE) were used to evaluate the prediction performance of the developed models in both calibration and validations stages. All four single models have very low R2 and PCC values (as low as 0.07) and very high MSE values (up to 4.92 wt %) for M1 and M2 in both calibration and validation phases. However, the ensemble ML models show R2 and PCC values of 0.99-1 and an MSE value of 0.01 wt % for M1, M2, and M3 input combinations. Therefore, ensemble paradigms improve the performance accuracy of single models by up to 58 and 62% in the calibration and validation phases, respectively. The ensemble paradigms predict with high accuracy the yield of ethylene and propylene in the catalytic cracking of crude oil and its fractions.

15.
Chemosphere ; 336: 139083, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37331666

RESUMO

Fluoride and nitrate contamination of groundwater is a major environmental issue in the world's arid and semiarid regions. This issue is severe in both developed and developing countries. This study aimed at assessing the concentration levels, contamination mechanisms, toxicity, and human health risks of NO3- and F- in the groundwater within the coastal aquifers of the eastern part of Saudi Arabia using a standard integrated approach. Most of the tested physicochemical properties of the groundwater exceeded their standard limits. The water quality index and synthetic pollution index evaluated the suitability of the groundwater and showed that all the samples have poor and unsuitable quality for drinking. The toxicity of F- was estimated to be higher than NO3-. Also, the health risk assessment revealed higher risks due to F- than NO3-. Younger populations had higher risks than elderly populations. For both F- and NO3-, the order of health risk was Infants > Children > Adults. Most of the samples posed medium to high chronic risks due to F- and NO3- ingestion. However, negligible health risks were obtained for potential dermal absorption of NO3-. Na-Cl and Ca-Mg-Cl water types predominate in the area. Pearson's correlation analysis, principal component analysis, regression models, and graphical plots were used to determine the possible sources of the water contaminants and their enrichment mechanisms. Geogenic and geochemical processes had greater impact he groundwater chemistry than anthropogenic activities. For the first time, these findings provide public knowledge on the overall water quality of the coastal aquifers and could help the inhabitants, water management authorities, and researchers to identify the groundwater sources that are most desirable for consumption and the human populations that are vulnerable to non-carcinogenic health risks.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Masculino , Adulto , Criança , Humanos , Idoso , Fluoretos/toxicidade , Fluoretos/análise , Nitratos/análise , Monitoramento Ambiental , Arábia Saudita , Poluentes Químicos da Água/análise , Água Subterrânea/química , Qualidade da Água , Compostos Orgânicos , Medição de Risco
16.
Heliyon ; 9(9): e19784, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37810075

RESUMO

The intrusion of seawater (SWI) into coastal aquifers is a major concern worldwide, affecting the quantity and quality of groundwater resources. The region of Saudi Arabia that lies along the eastern coast has been affected by SWI, making it crucial to accurately identify and monitor the affected areas. This investigation aimed to map the degree of seawater intrusion in a complex aquifer system in the study area using an integrated clustering analysis approach. The study collected 41 groundwater samples from wells penetrating multi-layered aquifers, and the samples were analyzed for physicochemical properties and major ions. Clustering analysis methods, including Hierarchical Clustering Analysis (double-clustering) (HCA-DC), K-mean (KMC), and fuzzy k-mean clustering (FKM), were employed to evaluate the spatial distribution and association of the groundwater properties. The results revealed that the analyzed GW samples were divided into four clusters with varying degrees of SWI. Clusters A, B, C, and D contained GW samples with very low (fsea of 1.9%), high (fsea of 14.9%), intermediate (fsea of 7.9%), and low (fsea of 5.2%) degrees of SWI, respectively. FKM clustering exhibited superior performance with a silhouette score of 0.83. Additionally, the study found a direct correlation between the degree of SWI and increased concentrations of boron, strontium, and iron, demonstrating SWI's impact on heavy metal levels. Notably, the boron concentration in cluster B, which endured high SWI, exceeded WHO guidelines. The study demonstrates the value of clustering analysis for accurately monitoring SWI and associated heavy metals. The findings can guide policies to mitigate SWI impacts and benefit groundwater-dependent communities. Further research can help develop effective strategies to mitigate SWI effects on groundwater quality and availability.

17.
Sci Total Environ ; 858(Pt 2): 159697, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334664

RESUMO

The growing increase in groundwater (GW) salinization in the coastal aquifers has reached an alarming socio-economic menace in Saudi Arabia and various places globally due to several natural and anthropogenic activities. Hence, evaluating the GW salinization is paramount to safeguarding the water resources planning and management. This study presents three different scenarios viz.: real field investigation, experimental laboratory analysis (using ion chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS), etc.), and artificial intelligence (AI) based metaheuristic optimization (MO) algorithms in Saudi Arabia. The main purpose of this study is to validate the obtained experimental-based analysis using hybrid MO techniques comprising of adaptive neuro-fuzzy inference system (ANFIS) hybridized with genetic algorithm (GA), particle swarm optimization (PSO), and biogeography-based optimization (BBO) for identification of GW salinization in the coastal region of eastern Saudi Arabia. Additionally, ArcGIS 10.3 software generates the prediction map based on ANFIS-GA, ANFIS-PSO, and ANFIS-BBO. Feature selection was assessed using the PSO algorithm, and four indices evaluated the estimated models, namely, root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), and standard deviation (SD). The simulated results are based on three variable input combinations, which showed that the ANFIS-PSO (MAE = 0.00439) algorithm had the highest accuracy (99 %), followed by the ANFIS-GA (MAE = 0.00767) and ANFIS-BBO (MAE = 0.0132) algorithms. Besides, Ca2+, Na+, Mg2+, and Cl- were the most influential parameters. The accuracy also demonstrated the potential reliability of MO algorithms based on spatial distribution mapping. The employed approach proved to be merit and reliable tool for water resources decision-makers in the coastal aquifer of Saudi Arabia. This approach is believed to improve water scarcity as one of the essential targets for Goal 6 of Sustainable Development Vision 2030 and the Kingdom in general.


Assuntos
Lógica Fuzzy , Água Subterrânea , Inteligência Artificial , Heurística , Arábia Saudita , Reprodutibilidade dos Testes , Algoritmos
18.
Chemosphere ; 331: 138726, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37116721

RESUMO

Due to the significant energy and economic losses brought on by the global oil spill, there has been an increased interest in oil-water separation. This study presents strong non-linear machine learning models (support vector regression (SVR) and Gaussian process regression (GPR)) with the Response surface method (RSM) to predict the oil flux and oil-water separation efficiency of wastewater using ceramic membrane technology. For the model development and prediction of oil flux (OF) and oil-water separation efficiency (OSE), oil concentration (mg/L), feed flow rate (mL/min), and pH were considered as input variables. The input variables are combined in three combinations to study the most contributing input features to the models' performance. Mean square error (MSE) and Nash-Sutcliffe coefficient efficiency (NSE) were used to assess the prediction performances of the developed models with the different number of input combinations considered in the study. For the two target variables (OF and OSE), GPR and SVR models were used to separately predict them. For OF, the SVR-2 [Combo-2] model (MSE = 0.9255 and NSE = 2.7976) performed better with higher prediction accuracy compared to GPR-2 [Combo-2] model (MSE = 0.763 and NSE = 6.437). In addition, for OSE, the GPR-3 [Combo-3] model (MSE = 0.995 and NSE = 0.5544) performed slightly better than SVR-3 [Combo-3] model (MSE = 0.992 and NSE = 0.8066). The results showed that the SVR model with the combo-2 and GPR-3 models for OF and OSE variables are the proposed models with the best performance and accuracy. This machine learning study will aid in better evaluating the function of materials such as ceramic in membrane performance features such as oil flux and rejection prediction, separation efficiency, water recovery, membrane fouling, and so on. As for academics and manufacturers, this machine learning (ML) strategy will boost performance and allow a better understanding of system governance.


Assuntos
Águas Residuárias , Purificação da Água , Água , Interações Hidrofóbicas e Hidrofílicas , Purificação da Água/métodos , Cerâmica
19.
Sci Rep ; 12(1): 10393, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729346

RESUMO

This study presents optimization and prediction of tribological behaviour of filled polytetrafluoroethylene (PTFE) composites using hybrid Taguchi and support vector regression (SVR) models. To achieve the optimization, Taguchi Deng was employed considering multiple responses and process parameters relevant to the tribological behaviour. Coefficient of friction (µ) and specific wear rate (Ks) were measured using pin-on-disc tribometer. In this study, load, grit size, distance and speed were the process parameters. An L27 orthogonal array was applied for the Taguchi experimental design. A set of optimal parameters were obtained using the Deng approach for multiple responses of µ and KS. Analysis of variance was performed to study the effect of individual parameters on the multiple responses. To predict µ and Ks, SVR was coupled with novel Harris Hawks' optimization (HHO) and swarm particle optimization (PSO) forming SVR-HHO and SVR-PSO models respectively, were employed. Four model evaluation metrics were used to appraise the prediction accuracy of the models. Validation results revealed enhancement under optimal test conditions. Hybrid SVR models indicated superior prediction accuracy to single SVR model. Furthermore, SVR-HHO outperformed SVR-PSO model. It was found that Taguchi Deng, SVR-PSO and SVR-HHO models led to optimization and prediction with low cost and superior accuracy.

20.
Life (Basel) ; 13(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36676028

RESUMO

The emergence of health informatics opens new opportunities and doors for different disease diagnoses. The current work proposed the implementation of five different stand-alone techniques coupled with four different novel hybridized paradigms for the clinical prediction of hepatitis C status among patients, using both sociodemographic and clinical input variables. Both the visualized and quantitative performances of the stand-alone algorithms present the capability of the Gaussian process regression (GPR), Generalized neural network (GRNN), and Interactive linear regression (ILR) over the Support Vector Regression (SVR) and Adaptive neuro-fuzzy inference system (ANFIS) models. Hence, due to the lower performance of the stand-alone algorithms at a certain point, four different novel hybrid data intelligent algorithms were proposed, including: interactive linear regression-Gaussian process regression (ILR-GPR), interactive linear regression-generalized neural network (ILR-GRNN), interactive linear regression-Support Vector Regression (ILR-SVR), and interactive linear regression-adaptive neuro-fuzzy inference system (ILR-ANFIS), to boost the prediction accuracy of the stand-alone techniques in the clinical prediction of hepatitis C among patients. Based on the quantitative prediction skills presented by the novel hybridized paradigms, the proposed techniques were able to enhance the performance efficiency of the single paradigms up to 44% and 45% in the calibration and validation phases, respectively.

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