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1.
Heliyon ; 10(11): e31755, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38841492

RESUMO

This paper presents a novel approach, the Gaussian Mixture Method-enhanced Cuckoo Optimization Algorithm (GMMCOA), designed to optimize power flow decision parameters, with a specific focus on minimizing fuel cost, emissions, network loss, and voltage deviation. GMMCOA integrates the strengths of COA and GMM while mitigating their individual limitations. While COA offers robust search capabilities, it suffers from initial parameter dependency and the risk of getting trapped in local optima. Conversely, GMM delivers high-speed performance but requires guidance to identify the best solution. By combining these methods, GMMCOA achieves an intelligent approach characterized by reduced parameter dependence and enhanced convergence speed. The effectiveness of GMMCOA is demonstrated through extensive testing on both the IEEE 30-bus and the large-scale 118-bus test systems. Notably, for the 118-bus test system, GMMCOA achieved a minimum cost of $129,534.7529 per hour and $103,382.9225 per hour in cases with and without the consideration of renewable energies, respectively, surpassing outcomes produced by alternative algorithms. Furthermore, the proposed method is benchmarked against the CEC 2017 test functions. Comparative analysis with state-of-the-art algorithms, under consistent conditions, highlights the superior performance of GMMCOA across various optimization functions. Remarkably, GMMCOA consistently outperforms its competitors, as evidenced by simulation results and Friedman examination outcomes. With its remarkable performance across diverse functions, GMMCOA emerges as the preferred choice for solving optimization problems, emphasizing its potential for real-world applications.

2.
J Chromatogr A ; 1707: 464326, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37639846

RESUMO

Preconcentration for on-site detection or subsequent determination is a promising technique for selective sensing explosive markers at low concentrations. Here, we report divinylbenzene monolithic polymer in its blank form (neat-DVB) and as a composite incorporated with sodalite topology zeolite-like metal-organic frameworks (3-ZMOF@DVB), as a sensitive, selective, and cost-effective porous preconcentrator for aliphatic nitroalkanes in the vapor phase as explosive markers at infinite dilution. The developed materials were fabricated as 18 cm gas chromatography (GC) monolithic capillary columns to study their separation performance of nitroalkane mixture and the subsequent physicochemical study of adsorption using the inverse gas chromatography (IGC) technique. A strong preconcentration effect was indicated by a specific retention volume adsorption/desorption ratio equal to 3 for nitromethane on the neat-DVB monolith host-guest interaction, and a 14% higher ratio was observed using the 3-ZMOF@DVB monolithic composite despite the low percentage of 0.7 wt.% of sod-ZMOF added. Furthermore, Incorporating ZMOF resulted in a higher percentage of micropores, increasing the degree of freedom more than bringing stronger adsorption and entropic-driven interaction more than enthalpic. The specific free energy of adsorption (ΔGS) values increased for polar probes and nitroalkanes, denoting that adding ZMOFs earned the DVB monolithic matrix a more specific character. Afterward, Lewis acid-base properties were calculated, estimating the electron acceptor (KA) and electron donor (KB) constants. The neat-DVB was found to have a Lewis basic character with KB/KA = 7.71, and the 3-ZMOF@DVB had a less Lewis basic character with KB/KA = 3.82. An increased electron-accepting nature can be directly related to incorporating sod-ZMOF into the DVB monolithic matrix. This work considers the initial step in presenting a portable explosives detector or preconcentrating explosive markers trace prior to more sophisticated analysis. Additionally, the IGC technique allows for understanding the factors that led to the superior adsorption of nitroalkanes for the developed materials.


Assuntos
Substâncias Explosivas , Estruturas Metalorgânicas , Zeolitas , Polímeros , Alcanos , Bases de Lewis
3.
J Chromatogr A ; 1694: 463922, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36931139

RESUMO

Organic monolithic columns are mainly used to separate macromolecules; however, many attempts to extend their performance toward small molecules were examined by incorporating micro- and nanoparticles. The incorporation technique enabled utilizing organic monoliths in gas chromatography (GC) for small molecules, which are still scarce. Here, we prepared a composite matrix of capillary monolithic columns of a zeolite-like metal-organic framework with a sodalite topology (sod-ZMOF) and Divinylbenzene polymer (DVB) for GC separations under 0.5 MPa. Relatively short DVB monolithic columns (18 cm long × 0.25 mm i.d.) incorporated with a tiny amount of sod-ZMOF nanoparticles (0.7 and 1.17 wt%) with an average particle size of 225 nm were successfully fabricated and used to separate linear alkanes and polar probes mixtures with increasing resolution up to 3.7 and 5.1 times, respectively, compared to a blank DVB monolithic column. A high-performance separation of linear alkanes series mixture (methane to decane) was exhibited in less than 2 min. McReynolds constants revealed that sod-ZMOF provided the composite monolith with a nonpolar character yielding a negative average polarity value smaller than the standard squalene column. An Excellent retention time of pentane and octane day-to-day reproducibility was achieved during 16 days and over more than 500 runs with RSD% of 2.25% and 3.3% using a composite monolithic column with 5 mg mL-1 sod-ZMOF (5-ZMOF@DVB). In addition, a qualitative determination of the gas mixture content of three commercially available Lighter gas cartridges was performed via the 5-ZMOF@DVB column. Finally, successfully separating an azeotropic freon mixture of difluoromethane (R-32) and pentafluoroethane (R-125) was achieved with a selectivity of up to 4.84. A further thermodynamic study related the preferential adsorption of R-125 to entropic factors rather than enthalpic while trapping inside ZMOF pores. This work sheds light on utilizing the infinite diversity of MOFs and combining their properties with high permeability and easily fabricated organic monoliths for GC separations of light molecules and gasses. Furthermore, the study highlights the role of GC as an easy and fast approach for the preliminary evaluation of the separation efficiency of porous polymers.


Assuntos
Fluorocarbonos , Estruturas Metalorgânicas , Zeolitas , Polímeros/química , Reprodutibilidade dos Testes , Alcanos/análise , Fluorocarbonos/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-35270199

RESUMO

The Arabian Peninsula (Arabia) is among the places to have experienced the greatest amount of warming during recent decades, and this trend is projected to continue. Specifics related to the characteristics (frequency, duration, and intensity) of extreme temperature events (ETEs) over Arabia as a whole are either largely outdated or limited only to specific areas. The seasonal ETE definitions commonly used in local studies are neither climatological- nor phenomenon-based. Using a novel and straightforward framework, the seasons of four extreme temperature types (extreme warm days/nights (EWDs/EWNs) and extreme cold days/nights (ECDs/ECNs)) were identified on the simultaneous basis of event occurrence and impact times. Assessments of ETE frequency, duration, and intensity and their recent changes were then provided based on the most recent climate data (1991-2020). Results showed that the use of traditional seasonal definitions (e.g., meteorological seasons) tends to assume a spatiotemporal homogeneity in the seasonality of ETEs and their potential risk levels throughout the year. The developed framework distinguished months with events that have larger potential impacts together with their local seasons. ETE seasons were found to vary at the regional and local scales and are better defined at both the local and phenomenon levels. Early extreme warm events were hotter, and those at locations with longer local warm seasons demonstrated higher intensities. ECDs tended to be more frequent at coastal locations, whereas ECNs were more frequent over southwestern Arabia. Early and late extreme cold events were much colder than those occurring mid-season. Trend analyses revealed generally increasing regional trends in the frequency of extreme warm events, whereas extreme cold events have declined. The duration (i.e., consecutive occurrences) and intensity of EWNs have been increasing at more locations, suggesting that urgent attention is needed within such an arid and hot climate type in which nighttime stress relief is already very limited.


Assuntos
Clima , Meteorologia , Arábia , Temperatura Baixa , Estações do Ano , Temperatura
5.
Medicina (Kaunas) ; 59(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36676716

RESUMO

The Human Immunodeficiency Virus (HIV) is a highly morphic, retrovirus that rapidly evolves through mutation as well as recombination. Because of the immunocompromised status in HIV patients, there is often a higher chance of acquiring different secondary infections followed by liver cirrhosis, hepatitis B & C, and HIV-associated nephropathy. The current study was conducted to see the prevalence of secondary infections, hematological and biochemical markers for liver and renal associated diseases, and to detect the envelope gene (GP41) in newly diagnosed HIV patients. A total of 37 samples were collected from HIV-positive patients registered in different hospital settings under the National AIDS control program. The collected samples were processed for hepatitis B, hepatitis C, hematological analysis, and biochemical analysis. To identify the envelope gene in newly diagnosed HIV patients, polymerase chain reaction (PCR) was performed using four gene-specific primers. The HIV infections were seen more in male as compared to females. A significant decrease in complete blood count was observed in HIV patients when compared to healthy individuals. There was a significant increase in aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine observed in HIV patients. No significant difference was observed in alkaline phosphatase (ALP), total bilirubin, and albumin levels when compared to healthy control. Anemia was observed in 59.4% of HIV patients. A total of three (8.1%) patients were found to be co-infected with hepatitis B and one (2.7 %) was co-infected with hepatitis C. Out of these 37 tested samples, a total of four showed the successful amplification of the envelope gene. This study provides platform for the health care facilitators to regularly monitor the signs, symptoms and clinical biomarkers of HIV-associated infections to prevent toxicity at an early stage to improve the quality of life (QoL) and minimize the mortality rate in HIV patients. Envelope gene mutating frequently results in drug resistance, and thus future research on polymorphism analysis will reveal points of substitutions to improve drug designing.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Hepatite C , Feminino , Humanos , Masculino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , HIV , Qualidade de Vida , Coinfecção/epidemiologia , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite C/complicações , Hepacivirus/genética , Prevalência , Biomarcadores
6.
Cureus ; 13(6): e15681, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34277271

RESUMO

Objective The disease outcome had been shown to improve with improving patient knowledge. The study had two objectives, firstly to assess the level of knowledge about cardiovascular diseases (CVDs) in the general population, and secondly, to provide written educational material regarding the risk factors, major symptoms, and the prevention of CVDs. Method The target population was the residents living in the Western region of Saudi Arabia, aged 18 years and above. All were invited to participate voluntarily. A pre-structured questionnaire was designed to collect data related to age, gender, marital status, education level, occupation, lifestyle habits, and a history of heart diseases, as well as cardiac symptoms, and risk factors. The educational material was provided after the questionnaire. Results The majority of the participants were female (74.8%). The risk factors most frequently identified were lack of exercise, stress, and obesity. Chest pain was recognized as a major symptom (87.6%). Other symptoms included dyspnea, syncope, and excessive sweating. The level of knowledge regarding the risk factors for cardiovascular disease was poor. Only 18.5% were knowledgeable about the risk factors. The majority (60%) could identify the preventable factors, including smoking cessation (92.2%), a high level of cholesterol (88.6%), and hypertension (78.7%). The majority (83.7%) read the educational material and 99% reported that the lecture increased their knowledge about cardiovascular disease. Conclusion Although cardiovascular risk factors are common, there is a big gap in the knowledge in our population. Further, alarming symptoms that bring the patients to medical care are also deficient. A call for action at different levels is urgent. Simple educational material in a basic language and virtual education are useful and cheap tools that must be practiced wherever possible. Education is welcomed by the participants.

7.
Ann Saudi Med ; 40(2): 126-135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32241164

RESUMO

BACKGROUND: Gingivitis is a site-specific inflammatory condition initiated by dental biofilm accumulation. The accumulation of dental plaque on the gingival margin triggers inflammatory effects that can become chronic. In addition to its local effect, gingival inflammation has recently been suggested to have an impact on general health. OBJECTIVE: Determine the prevalence of gingivitis and its relationship to oral hygiene practices in high school children in Saudi Arabia. DESIGN: Cross-sectional. SETTING: High schools from different regions in Saudi Arabia. PATIENTS AND METHODS: Periodontal examinations were conducted on a randomly selected sample of high school children between the ages of 15 and 19 years. Gingival and plaque indices, probing depth, clinical attachment level, oral hygiene practices and sociodemographic characteristics were recorded. Data were analyzed using descriptive statistics, chi-square and the independent t test. MAIN OUTCOME MEASURE: Prevalence of gingivitis as defined by mean gingival index. SAMPLE SIZE: 2435 high school students. RESULTS: Twenty-one percent of the sample had slight gingivitis, 42.3% had moderate, and 1.8% had severe. Gender, toothbrushing, tongue brushing, plaque index, and the percentage of pocket depth (PD) ≥4 mm showed a significant relationship with the severity of gingivitis. Almost 39.3% of females had a healthy periodontal status when compared to males (30.7%). Thirty-five percent (35.5%) of students who brushed their teeth had a healthy periodontium compared to 26.9% who did not brush. The mean plaque index was significantly higher in students with severe gingivitis when compared to students with healthy periodontium (2.4 vs. 0.79, respectively). CONCLUSION: Gingivitis prevalence was high compared with Western countries in a nationally representative sample of high school students in Saudi Arabia and was influenced by oral hygiene practices. LIMITATIONS: The half-mouth study design may underestimate disease prevalence. Data on oral hygiene practices was self-reported and may thus have been affected by social desirability bias. CONFLICT OF INTEREST: None.


Assuntos
Índice de Placa Dentária , Gengivite/epidemiologia , Higiene Bucal/estatística & dados numéricos , Índice Periodontal , Adolescente , Feminino , Bolsa Gengival/epidemiologia , Humanos , Masculino , Prevalência , Arábia Saudita/epidemiologia , Índice de Gravidade de Doença , Fatores Sexuais , Adulto Jovem
8.
Ann Saudi Med ; 39(4): 244-250, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31381369

RESUMO

BACKGROUND: The periodontal tissues are continuously exposed to specific bacterial components that have the ability to alter many local functions. Normal endogenous infections in healthy mouths cause disease when their numbers increase significantly. OBJECTIVE: Determine the percentage of different periodontal pathogenic bacteria and their association with periodontal status. DESIGN: Cross-sectional, analytical. SETTINGS: School children of both genders in Saudi Arabia. PATIENTS AND METHODS: Clinical examination consisted of measurement of the gingival and periodontal supporting tissue including attachment loss, probing pocket depth and furcation involvement following the National Health and Nutrition Examination Survey (NHANES) and taking samples of the subgingival bacterial flora. MAIN OUTCOME MEASURES: The percentage of periodontal pathogenic bacteria and its association with periodontal status in Saudi Arabia. SAMPLE SIZE: Bacterial samples were collected from 277 subjects. RESULTS: Aggregatibacter actinomycetemcomitans was present in 21.7% of the subjects, Porphyromonas gingivalis in 21.3%; Tannerella forsythia in 10.1%; Treponema denticola in 34.7% and Prevotella inter-media in 12.3%. The red complex bacteria were found in 2.9% of the subjects. CONCLUSIONS: The percentages of bacteria varied but only T denticola was significantly associated with periodontal breakdown. In addition, the presence of more than 2 of the 5 species tested were significantly associated with tissue damage. LIMITATIONS: Cannot be generalized to all of Saudi Arabia. Larger controlled studies are needed. CONFLICT OF INTEREST: None.


Assuntos
Bactérias/isolamento & purificação , Gengiva/microbiologia , Doenças Periodontais/microbiologia , Periodonto/microbiologia , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Doenças Periodontais/epidemiologia , Arábia Saudita/epidemiologia , Treponema denticola/isolamento & purificação
9.
Materials (Basel) ; 12(5)2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30862056

RESUMO

In this work, microemulsion method has been followed to synthesize vanadium-doped Zn1-xVxO (with x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.10) nanoparticles. The prepared samples are characterized by several techniques to investigate the structural, morphology, electronic, functional bonding, and optical properties. X-ray diffractometer (XRD) analysis confirms the wurtzite phase of the undoped and V-doped ZnO nanoparticles. Variation in the lattice parameters ensures the incorporation of vanadium in the lattice of ZnO. Scanning electron microscopy (SEM) shows that by increasing contents of V ions, the average particle size increases gradually. X-ray Absorption Near Edge Spectroscopy (XANES) at the V L3,2 edge, oxygen K-edge, and Zn L3,2 edge reveals the presence and effect of vanadium contents in the Zn host lattice. Furthermore, the existence of chemical bonding and functional groups are also asserted by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). UV⁻Visible analysis shows that by increasing V⁺ contents, a reduction up to 2.92 eV in the energy band gap is observed, which is probably due to an increase in the free electron concentration and change in the lattice parameters.

10.
Sensors (Basel) ; 20(1)2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31905646

RESUMO

This work reviews design aspects of liquid metal antennas and their corresponding applications. In the age of modern wireless communication technologies, adaptability and versatility have become highly attractive features of any communication device. Compared to traditional conductors like copper, the flow property and lack of elasticity limit of conductive fluids, makes them an ideal alternative for applications demanding mechanically flexible antennas. These fluidic properties also allow innovative antenna fabrication techniques like 3D printing, injecting, or spraying the conductive fluid on rigid/flexible substrates. Such fluids can also be easily manipulated to implement reconfigurability in liquid antennas using methods like micro pumping or electrochemically controlled capillary action as compared to traditional approaches like high-frequency switching. In this work, we discuss attributes of widely used conductive fluids, their novel patterning/fabrication techniques, and their corresponding state-of-the-art applications.

11.
Comput Math Methods Med ; 2019: 4198462, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31915460

RESUMO

Speech parameters may include perturbation measurements, spectral and cepstral modeling, and pathological effects of some diseases, like influenza, that affect the vocal tract. The verification task is a very good process to discriminate between different types of voice disorder. This study investigated the modeling of influenza's pathological effects on the speech signals of the Arabic vowels "A" and "O." For feature extraction, linear prediction coding (LPC) of discrete wavelet transform (DWT) subsignals denoted by LPCW was used. k-Nearest neighbor (KNN) and support vector machine (SVM) classifiers were used for classification. To study the pathological effects of influenza on the vowel "A" and vowel "O," power spectral density (PSD) and spectrogram were illustrated, where the PSD of "A" and "O" was repressed as a result of the pathological effects. The obtained results showed that the verification parameters achieved for the vowel "A" were better than those for vowel "O" for both KNN and SVM for an average. The receiver operating characteristic curve was used for interpretation. The modeling by the speech utterances as words was also investigated. We can claim that the speech utterances as words could model the influenza disease with a good quality of the verification parameters with slightly less performance than the vowels "A" as speech utterances. A comparison with state-of-the-art method was made. The best results were achieved by the LPCW method.


Assuntos
Influenza Humana/diagnóstico , Influenza Humana/fisiopatologia , Idioma , Processamento de Sinais Assistido por Computador , Espectrografia do Som , Qualidade da Voz , Análise de Ondaletas , Algoritmos , Área Sob a Curva , Humanos , Masculino , Fonação , Fonética , Curva ROC , Arábia Saudita , Fala , Acústica da Fala , Máquina de Vetores de Suporte , Voz , Distúrbios da Voz , Adulto Jovem
12.
Am J Med Sci ; 346(6): 473-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23811576

RESUMO

BACKGROUND: The purpose was to evaluate the significance of panoramic radiomorphometric indices (mandibular cortical index [MCI], mental index [MI] and panoramic mandibular index [PMI]) as useful tools for identifying osteoporosis. METHODS: One hundred healthy women aged ≥ 30 years were included. Digital panoramic images and bone mineral density (BMD) of the lumbar spines were recorded. Radiomorphometric indices (MCI, MI and PMI) were measured and categorized. RESULTS: Interobserver agreements were kappa = 0.922 for the MCI and alpha = 0.902 and 0.702 for the PMI and MI, respectively. The indices MI, PMI and BMD showed a statistically significant positive correlation with the t score (r = 0.47, 0.36 and 0.96, respectively). The MI showed a statistically significant positive correlation with the PMI (r = 0.72). Sensitivity, specificity and diagnostic accuracy of the MI at a cutoff point of 4.5 mm were 76.9%, 54.1% and 63%, respectively, whereas for the MCI were 66.7%, 75.4% and 72%, respectively. CONCLUSIONS: Panoramic indices (MI, PMI and MCI) were positively correlated with the t score and BMD of the lumbar spines. The MCI was found to be the most reproducible index.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Programas de Rastreamento/métodos , Osteoporose/diagnóstico por imagem , Radiografia Panorâmica/métodos , Absorciometria de Fóton , Adulto , Idoso , Densidade Óssea , Cefalometria , Feminino , Humanos , Vértebras Lombares/anatomia & histologia , Mandíbula/anatomia & histologia , Pessoa de Meia-Idade , Variações Dependentes do Observador , Osteoporose/diagnóstico , Reprodutibilidade dos Testes , Arábia Saudita , Sensibilidade e Especificidade
13.
Saudi Med J ; 34(6): 609-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23756926

RESUMO

OBJECTIVES: To determine whether soft tissue augmentation prior to block grafting will minimize post-block grafting soft tissue complications. METHODS: This longitudinal controlled pilot study was conducted at the Faculty of Dentistry, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia from October 2010 to January 2013. Fourteen sites requiring block grafting were divided into 2 groups: Group A - 7 sites in 6 patients were subjected to monocortical block graft (control); and Group B - 7 sites in 6 patients were subjected to soft tissue graft through new tunnel technique, followed by monocortical block graft (test). RESULTS: In Group A, 2 patients had wound dehiscence and graft exposure. The first that had an exposure of 3x4 mm resulted in 45% resorption of the graft. The second had an exposure of 4x5 mm followed by infection, which resulted in 75% resorption of the graft. In the other 5 cases, sites healed with no complications and minimal resorption (0-15%). In Group B - there were generalized 1-2 mm increases in the thickness of soft tissue following soft tissue graft. Recipient sites healed with no complications or infection following block grafting. Block graft resorption ranged from 0-15%. CONCLUSION: More complications were seen in those patients who did not receive soft tissue augmentation, thus demonstrating the importance of soft tissue preparation prior to block grafting, especially in patients having thin soft tissue.


Assuntos
Aumento do Rebordo Alveolar/efeitos adversos , Complicações Pós-Operatórias , Adulto , Aumento do Rebordo Alveolar/métodos , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Projetos Piloto
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