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1.
J Environ Manage ; 351: 119926, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154226

RESUMO

This study investigates-for the first time-the synthesis of a novel Ca-rich biochar (N-Ca-B) and its potential use for phosphorus (P) recovery from both synthetic solutions (SS) and treated urban wastewater (TUW) in a continuous stirring tank reactor (CSTR) mode. The novel biochar was synthesized by pyrolysis at 900 °C of a mixture composed of three different materials: animal biomass (poultry manure; PM), lignocellulosic waste (date palm fronds; DPFs), and abundant mineral waste (waste marble powder; WMP). Characterization of N-Ca-B showed that it has good textural properties: well-developed porosity, and high specific surface area. Furthermore, high calcium hydroxide (Ca(OH)2) and calcium oxides (CaO) nanoparticle loads were observed on the biochar surface. The dynamic CSTR assays indicated that the P recovery efficiency mainly depended on the biochar mass, P influent concentration, and, especially, the Ca content of the feeding solution. Owing to its richness in Ca cations, TUW exhibited the highest adsorbed P amount (109.2 mg g-1), i.e., about 14% larger than the SS. P recovery occurs through precipitation as hydroxyapatite, surface complexation, and electrostatic interactions with positively charged biochar particles. In real-world scenarios, CSTR systems can be applied as a tertiary treatment step in existing wastewater treatment plants (WWTPs). Decanted P-loaded biochar can be used in agriculture as a slow-release fertilizer instead of commercial products.


Assuntos
Carbonato de Cálcio , Cálcio , Animais , Fósforo , Pós , Carvão Vegetal , Águas Residuárias
2.
Sleep Breath ; 27(1): 355-362, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35469371

RESUMO

PURPOSE: To describe the effect of seasonal variations on sleep patterns in a hot climate Arab region. METHODS: This is a cross-sectional study that included healthy Omani subjects of both genders between ages 18 and 59 years. Data for sleep pattern identification in summer and winter were collected from participants using an actigraphy wristband. RESULTS: Among 321 participants, in summer seasons, a polyphasic sleep pattern (40%) prevailed over other sleep patterns (P < 0.001). While in the winter season, monophasic sleep (31%) was the dominant pattern (P < 0.001). Subjects slept longer during the winter seasons with total hours of sleep during the day 48 min longer than in the summer, though the difference was not statistically significant (P > 0.05), while siesta duration in the summer was significantly longer (13 min, P < 0.01). In summer, the sleep quality was good (PSQI ≤ 5); however, it was poor (PSQI > 5) in winter (P < 0.05). Night sleep duration, daytime sleepiness, and sleep latency were not statistically different between the summer and winter seasons. CONCLUSION: Sleep patterns may be influenced by seasonal changes. A polyphasic sleep pattern prevailed in summer while a monophasic pattern was the predominant sleep pattern in winter. In summer, the sleep quality was good and the siesta duration was longer compared to the winter.


Assuntos
Árabes , Sono , Feminino , Humanos , Masculino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estações do Ano , Estudos Transversais , Qualidade do Sono
3.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36499359

RESUMO

Direct alcohol fuel cells are deemed as green and sustainable energy resources; however, CO-poisoning of Pt-based catalysts is a critical barrier to their commercialization. Thus, investigation of the electrochemical CO oxidation activity (COOxid) of Pt-based catalyst over pH ranges as a function of Pt-shape is necessary and is not yet reported. Herein, porous Pt nanodendrites (Pt NDs) were synthesized via the ultrasonic irradiation method, and its CO oxidation performance was benchmarked in different electrolytes relative to 1-D Pt chains nanostructure (Pt NCs) and commercial Pt/C catalyst under the same condition. This is a trial to confirm the effect of the size and shape of Pt as well as the pH of electrolytes on the COOxid. The COOxid activity and durability of Pt NDs are substantially superior to Pt NCs and Pt/C in HClO4, KOH, and NaHCO3 electrolytes, respectively, owing to the porous branched structure with a high surface area, which maximizes Pt utilization. Notably, the COOxid performance of Pt NPs in HClO4 is higher than that in NaHCO3, and KOH under the same reaction conditions. This study may open the way for understanding the COOxid activities of Pt-based catalysts and avoiding CO-poisoning in fuel cells.


Assuntos
Medicina , Nanoestruturas , Eletrólitos , Oxirredução , Tomografia por Emissão de Pósitrons
4.
Sleep Breath ; 25(4): 1885-1891, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33484386

RESUMO

PURPOSE: To investigate the agreement in sleep pattern recording by self-reported sleep questionnaires and actigraphy in adults. METHODS: This is a cross-sectional study. Men and women who met inclusion criteria were recruited for this study. The inclusion criteria were apparently healthy Omani nationals ages 19 to 50 years. Sleep questionnaires were randomly distributed in Muscat either directly or via electronic and paper announcements. Data were collected from the participants using the self-reported questionnaires with four piloted questions for sleep pattern identification and through the actigraphy wristband given to subjects to wear for a week. Cohen's kappa test was performed for agreement analysis. RESULTS: A total of 964 Omani subjects between ages 18 and 59 years of both genders were recruited and completed the questionnaires successfully. Out of these, only 321 subjects wore the actigraphy wristband for 1 week (response rate = 33%). Agreement analysis reported a mild level of agreement for the monophasic (41%), moderate level for biphasic (59%), and good level for polyphasic (70%) sleep patterns. The overall agreement level of sleep patterns between the two methods was 57%. There is a low specificity of self-reported assessment in reporting sleep pattern. CONCLUSION: The average agreement level of subjective versus objective assessments of sleep patterns was moderate at 57% and self-reported sleep pattern is not specific. The study recommends the use of actigraphy along with sleep questionnaires for accurate assessment of sleep patterns in cohort studies.


Assuntos
Actigrafia , Autorrelato , Sono , Actigrafia/normas , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato/normas , Sono/fisiologia , Adulto Jovem
5.
Angew Chem Int Ed Engl ; 60(39): 21242-21249, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34378296

RESUMO

Mesoporous carbon nitrides with C3 N5 and C3 N6 stoichiometries created a new momentum in the field of organic metal-free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C3 N5.4 using ultra-stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen-containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m2 g-1 and demonstrates excellent CO2 adsorption per unit surface area of 47.54 µmol m-2 , which is due to the existence of abundant free NH2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g-1 ) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules.

6.
Sleep Breath ; 23(4): 1331-1339, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31041780

RESUMO

PURPOSE: The state of knowledge about the effect of sleep deprivation on the immune system is scarce and conflicting. It would therefore be useful to investigate the consequences of sleep deprivation on the immune system. We have studied the effect of sleep deprivation on the changes in neutrophil functions, and the ex vivo proliferative pattern of CD4+ T lymphocytes in relationship with blood cytokine and chemokine levels due to the crucial role of these cells in mounting potent immune responses. METHODS: Healthy volunteers were followed for 3 weeks. They had normal sleep in weeks 1 and 3 and they were sleep-deprived on week 2, sleeping < 6 h per 24 h, a pattern similar to sleep behaviors of many chronically sleep-deprived individuals. We assessed the levels of Th1/Th2 and inflammatory cytokines and chemokines, CD4+ T cells, and the NADPH oxidase activation and phagocytic functions in neutrophils. RESULTS: Our results suggest that sleep deprivation leads to a decreased neutrophil capacity to phagocytose bacteria and activate NADPH oxidase (p < 0.05). Sleep deprivation was associated with a potential increase in CXCL9 levels and decrease in CXCL10/CXCL9 and CCL5/CXCL9 ratios (p < 0.05). Furthermore, our results suggest that the decrease in CD4+ T cell due to sleep deprivation was not associated with changes in their proliferation as observed by Ki67 levels, but rather, it correlated with changes in CXCL10/CXCL9 ratio (p < 0.05). CONCLUSIONS: Sleep deprivation may lead to a decreased phagocytosis and NADPH oxidase activity in neutrophils and a decrease in the levels of CD4+ T cells which is related to changes in the Th1-related chemokine balance.


Assuntos
Contagem de Linfócito CD4 , Quimiocinas/fisiologia , Neutrófilos/fisiologia , Privação do Sono/imunologia , Equilíbrio Th1-Th2/fisiologia , Adulto , Proliferação de Células , Citocinas/sangue , Feminino , Humanos , Masculino , NADPH Oxidases/sangue , Fagocitose/imunologia , Valores de Referência
7.
BMC Genomics ; 19(1): 690, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30231936

RESUMO

BACKGROUND: The scalloped spiny lobster (Panulirus homarus) is a popular seafood commodity worldwide and an important export item from Oman. Annual catches in commercial fisheries are in serious decline, which has resulted in calls for the development of an integrated stock management approach. In Oman, the scalloped spiny lobster is currently treated as a single management unit (MU) or stock and there is an absence of information on the genetic population structure of the species that can inform management decisions, particularly at a fine-scale level. This work is the first to identify genome-wide single nucleotide polymorphisms (SNPs) for P. homarus using Diversity Arrays Technology sequencing (DArT-seq) and to elucidate any stock structure in the species. RESULTS: After stringent filtering, 7988 high utility SNPs were discovered and used to assess the genetic diversity, connectivity and structure of P. homarus populations from Al Ashkharah, Masirah Island, Duqm, Ras Madrakah, Haitam, Ashuwaymiyah, Mirbat and Dhalkut landing sites. Pairwise FST estimates revealed low differentiation among populations (pairwise FST range = - 0.0008 - 0.0021). Analysis of genetic variation using putatively directional FST outliers (504 SNPs) revealed higher and significant pairwise differentiation (p < 0.01) for all locations, with Ashuwaymiyah being the most diverged population (Ashuwaymiyah pairwise FST range = 0.0288-0.0736). Analysis of population structure using Discriminant Analysis of Principal Components (DAPC) revealed a broad admixture among P. homarus, however, Ashuwaymiyah stock appeared to be potentially under local adaptive pressures. Fine scale analysis using Netview R provided further support for the general admixture of P. homarus. CONCLUSIONS: Findings here suggested that stocks of P. homarus along the Omani coastline are admixed. Yet, fishery managers need to treat the lobster stock from Ashuwaymiyah with caution as it might be subject to local adaptive pressures. We emphasize further study with larger number of samples to confirm the genetic status of the Ashuwaymiyah stock. The approach utilised in this study has high transferability in conservation and management of other marine stocks with similar biological and ecological attributes.


Assuntos
Adaptação Fisiológica , Fluxo Gênico , Marcadores Genéticos , Genoma , Palinuridae/genética , Polimorfismo de Nucleotídeo Único , Animais , Genética Populacional
8.
J Hered ; 108(4): 361-368, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28444202

RESUMO

Horse breeders rely heavily on pedigrees for identification of ancestry in breeding stock. Inaccurate pedigrees may erroneously assign individuals to false lineages or breed memberships resulting in wrong estimates of inbreeding and coancestry. Moreover, discrepancies in pedigree records can lead breeders seeking to limit inbreeding into making misguided breeding decisions. Genome-wide SNPs provide a quantitative tool to aid in the resolution of lineage assignments and the calculation of genomic measures of relatedness. The aim of this project was to pilot a comparison between pedigree and genomic relatedness and inbreeding measures in a herd of 36 pedigreed Egyptian Arabian horses genotyped using the Equine SNP70 platform (Geneseek, Inc.). Moreover, we sought to estimate the minimum number of markers sufficient for genomic inbreeding calculations. Pedigree inbreeding values were moderately correlated with genomic inbreeding values (r = 0.406), whereas genomic relationships and pedigree relationships have a high correlation (r = 0.77). Although first degree relationships were successfully reconstructed, more distant relationships were difficult to resolve. Multi-dimensional scaling and clustering analysis agreed with within-herd pedigree information. In comparing the herd to a reference sample of United States, Polish, and Egyptian Arabian horses, the herd's historically recorded Egyptian lineage was successfully recovered. We conclude that genomic estimates of inbreeding and relationships are superior to their pedigree counterparts. They can be thus utilized in conservation of valuable lines of livestock, and in breeds at risk for loss of genomic diversity. We also postulate a minimum of 2000 markers in linkage equilibrium to be used for inbreeding estimation.


Assuntos
Genética Populacional , Cavalos/genética , Endogamia , Animais , Cruzamento , Análise por Conglomerados , Feminino , Genômica , Genótipo , Homozigoto , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
9.
J Clin Sleep Med ; 20(6): 959-966, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38318866

RESUMO

STUDY OBJECTIVES: We investigated the association between different sleep patterns and inflammatory and oxidative stress biomarkers in adults. METHODS: A total of 321 consented adults who fulfilled the inclusion criteria were recruited in this cross-sectional study. The inclusion criteria were mainly based on apparently healthy adults aged 18-59 years. To identify sleep patterns, participants were requested to wear the actigraph for 1 week for 24 hours a day. Fasting blood was collected from each participant at day 8. The blood serum was analyzed for inflammatory and oxidative stress biomarkers. Sleep patterns were defined as monophasic (1 episode of night sleep) biphasic (2 episodes of sleep; night and aternoon siesta), and polyphasic sleep pattern (3 or more sleep episodes). RESULTS: There was no correlation between night sleep duration, total sleep in 24 hours, and napping among inflammatory and oxidative stress biomarkers: high-sensitivity C-reactive protein, malondialdehyde, total glutathione, and basal oxidizability status. Actigraphy reports showed 3 sleep patterns in this cohort, monophasic (24.3%), biphasic-napping (45.2%) and polyphasic (30.5%). Individuals with segmented sleep patterns were significantly associated with oxidative stress biomarkers. A polyphasic sleep pattern was significantly associated with higher basal oxidizability status (P = .023), whereas a biphasic sleep pattern showed higher malondialdehyde (P = .036) as compared to a monophasic sleep pattern. Total glutathione was significantly higher in monophasic sleepers (P = .046). There was no difference in serum high-sensitivity C-reactive protein among all sleep patterns. CONCLUSIONS: Segmented sleep in polyphasic and biphasic sleep patterns is associated with higher serum malondialdehyde and basal oxidizability status in particular. Further studies are recommended on the cardiometabolic impact of oxidative stress biomarkers in individuals with segmented sleep. CITATION: Al Lawati I, Zadjali F, Al-Abri MA. Elevated oxidative stress biomarkers in adults with segmented sleep patterns. J Clin Sleep Med. 2024;20(6):959-966.


Assuntos
Actigrafia , Biomarcadores , Estresse Oxidativo , Sono , Humanos , Estresse Oxidativo/fisiologia , Biomarcadores/sangue , Adulto , Masculino , Feminino , Estudos Transversais , Actigrafia/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto Jovem , Sono/fisiologia , Adolescente , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Inflamação/sangue , Malondialdeído/sangue
10.
Chemosphere ; 350: 141053, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154669

RESUMO

This work reports the development of multifunctional or polymorphous surfaces using zinc oxide (ZnO) nanorods, silica (SiO2), and fluoropolymer functionalization in a sequential process. Firstly, zinc oxide nanorods were grown on activated carbon cloth (ACC) using a simple low-temperature synthesis process. ZnO nanorods-coated ACC substrate was applied to investigate the antimicrobial properties, and the results showed inhibition of 50% for Escherichia coli (E.coli) and 55% for Bacillus subtilis (B.subtilis) over 48 h of incubation time. Subsequent in-situ modification of silica nanoparticles like layer on ZnO nanorods-coated ACC surface was developed and used as an electrode for brackish water desalination in a capacitive deionization system. ZnO-SiO2 modified ACC surface enhanced the desalination efficiency by 1.6 times, the salt removal rate (SRR) by threefold, and the durability (fouling prevention) for long-term usage compared to pristine ACC. Further modification of the ZnO-SiO2-ACC surface using fluoropolymer rendered the surface superhydrophobic and oleophilic. Vegetable (1.4 g/g) and crude oil (1.6 g/g) adsorption capacities were achieved for modified surface which was 70% enhancement compared with pristine ACC. The dynamic oil spill adsorption test exhibited the complete removal of oil spills on water surfaces within a few seconds, suggesting a potential application in oil spill cleaning.


Assuntos
Nanotubos , Poluição por Petróleo , Óxido de Zinco , Carvão Vegetal , Óxido de Zinco/química , Polímeros de Fluorcarboneto , Dióxido de Silício , Antibacterianos/farmacologia , Nanotubos/química
11.
J Colloid Interface Sci ; 659: 718-727, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38211489

RESUMO

Herein, we present a novel microwave-assisted method for the synthesis of palladium nanoparticles (PdNPs) supported by Limonia acidissima Groff tree extract gum. The synthesized PdNPs were characterized using various analytical techniques, including FTIR, SEM, TEM, UV-visible, and powder XRD analyses. TEM and XRD analysis confirmed that the synthesized LAG-PdNPs are highly crystalline nature spherical shapes with an average size diameter of 7-9 nm. We employed these gum-capped PdNPs to investigate their peroxidase-like activity for colorimetric detection of hydrogen peroxide (H2O2) and glucose. The oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2, catalyzed by PdNPs, produces oxidation products quantified at 652 nm using spectrophotometry. The catalytic activity of PdNPs was optimized with respect to temperature and pH. The developed method exhibited a linear range of detection from 1 to 50 µm, with detection limits of 0.35 µm for H2O2 and 0.60 µm for glucose.


Assuntos
Colorimetria , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Paládio/química , Peróxido de Hidrogênio/análise , Micro-Ondas , Glucose/análise
12.
Oman Med J ; 39(1): e589, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38567166

RESUMO

Objectives: To estimate the incidence of pituitary adenomas (PA) in adult Omani patients and describe its epidemiological, clinical, and radiological characteristics. Methods: In this longitudinal, descriptive study, we reviewed the records of all PA patients from January 2015 to January 2020 who presented at the endocrinology facilities at Sultan Qaboos University Hospital, Muscat. Results: The participants comprised of 112 Omani patients with PA. The incidence of PA among all adult patients at Sultan Qaboos University Hospital (inpatient and outpatient) over five years (2015-2020) was 0.23%. The cohort had a mean age of 41.0±15.0 years. Of the 112 patients included in this study, 79 (70.5%) were women. Nearly half (51; 45.5%) of adenomas were prolactinomas while 46 (41.1%) were non-functioning adenomas, and seven (6.3%) were growth hormone-secreting adenomas while six (5.4%) were adrenocorticotropic hormone secreting adenomas. Headache was present in 67 (59.8%) patients, followed by visual field defects (40; 35.7%), galactorrhea (26; 23.2%), and fatigue (19; 17.0%). The majority of women (45/79; 57.0%) presented with menstrual cycle abnormalities. Radiological appearances were nearly equally distributed between micro- and macroadenomas. Most cases (58/112; 52.0%) of PA were treated medically by cabergoline, octreotide, and replacement therapies such as hydrocortisone and thyroxin, 38 (33.9%) were treated surgically (mainly by trans-sphenoidal pituitary resection), and the remaining 10 (8.9%) cases were subjected to radiotherapy. Medical treatment combined with surgery was employed for 15 (13.4%) patients. Conclusions: In our investigation, PA was primarily prevalent among Omani female patients, and the most common subtype of pituitary tumors was prolactinomas. The most common presentation symptom was headaches; most female patients had menstrual irregularities. Medical treatment was the primary approach for the applicable types of PAs, while surgery and radiotherapy were found to be secondary and tertiary treatment options, respectively.

13.
J Clin Sleep Med ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38895993

RESUMO

STUDY OBJECTIVES: This study assessed the current state of sleep medicine accreditation and training in Asia by conducting a comprehensive survey across 29 Asian countries and regions facilitated by the Asian Society of Sleep Medicine (ASSM) to identify existing gaps and provide recommendations for future enhancements. METHODS: The ASSM Education Task Force Committee designed a survey to gather data on accreditation, education, and training standards in sleep medicine, including information on challenges in enhancing education in the field. RESULTS: With an 86% (25 countries/regions) response rate, the survey showed that sleep medicine is recognized as an independent specialty in just nine countries/regions (36% of the countries/regions surveyed). Ten countries/regions have established sleep medicine training programs, with Japan and Saudi Arabia offering it as a distinct specialty. Significant disparities in training and accreditation standards were identified, with many countries/regions lacking formalized training and practice guidelines. The survey also revealed that most local sleep societies across Asia support the development of an Asian Sleep Medicine Training Curriculum led by the ASSM. However, several barriers significantly impede the establishment and development of sleep medicine training programs, including the scarcity of trained specialists and technologists and the absence of national accreditation for sleep medicine. CONCLUSIONS: The survey highlights the need for standardized sleep medicine training and accreditation across Asia. Developing an Asian Sleep Medicine Training Curriculum and promoting ASSM accreditation guidelines are key recommendations. Implementing these strategies is essential for advancing sleep medicine as a widely recognized discipline throughout Asia.

14.
Oman Med J ; 38(2): e477, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37009205

RESUMO

Sleep is an imperative physiological aspect that plays a vital role in maintaining hormonal and humeral functions of the body and hence a healthy life. Circadian rhythms are daily oscillations in human activities and physiology that prepare human beings to better react to and anticipate challenges in the surrounding environment, which are a consequence of diurnal changes of day and night. The sleep/wake cycle is one of the most prominent manifestations of the circadian rhythm and communicates tightly with the immune system with daily oscillation of immunity. Sleep deprivation is now recognized as a common condition inherent to modern society, and it is detrimental to certain body functions, particularly immune function. The aim of this review is to explore the role of sleep in maintaining a healthy immune system during the COVID-19 pandemic. The review discusses sleep-regulatory substances that are linked to host defense mechanisms such as interleukin-1ß, interleukin-6, tumor necrosis factor alpha, and interferon gamma. Cytokine levels also fluctuate with sleep/wake homeostasis and our review explores the relationship between sleep and cytokines and proposed therapeutics. The review will also cover sleep and immune response in children, adolescents, and healthcare workers, and finally it will touch on the effect of obstructive sleep apnea on immune response and the severity of COVID-19.

15.
Heliyon ; 9(11): e21802, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38045201

RESUMO

Ammonia is one of the most produced chemicals around the world due to its various uses. However its traditional production process is associated with high fossil fuel consumption. To avoid this, the production of green ammonia can be done, and one of the considered production methods is water electrolysis, where the hydrogen needed for the manufacturing of ammonia is produced using solar energy. In this work, multi-objective optimization (MOO) is carried out for two ammonia synthesis processes with water electrolysis. One process uses solar energy to generate electricity for the whole process (Green ammonia), while the other uses natural gas for the same purpose (non-green ammonia) on a small production scale. The process is simulated using ProMax 5.0 and MOO is done using Excel-based MOO with I-MODE algorithm. Several MOO cases are solved with different objectives like CO2 emissions and energy (ENG) minimization, and Profit and Purity maximization in two and three objective cases. To conduct the work, several decision variables are selected like the operating temperatures and pressures of different streams in addition to the flow rate of nitrogen and water. Some constraints regarding the purity and reactors temperature are considered as well. The obtained results showed that the profit of green ammonia process (ranges between 0.7 and 80 M$/yr) is lower compared to the non-green process (ranges between 0.8 and 4.4 M$/yr). On the other hand, huge CO2 emissions (up to 38000 tons/yr) are produced in the non-green process compared to almost zero emissions with the green process. In most cases, water and nitrogen flow rates showed a high influence on the results and caused conflict between the objectives.

16.
Discov Nano ; 18(1): 45, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-37382758

RESUMO

In this study, systematic development of a portable sensor for the rapid detection of Escherichia coli (E. coli) and Exiguobacterium aurantiacum (E. aurantiacum) was reported. A conductive glass was utilized as a substrate and developed the electrode patterns on it. Trisodium citrate (TSC) and chitosan-stabilized gold nanoparticles (AuNPs) (CHI-AuNP-TSC) and chitosan-stabilized AuNPs (CHI-AuNP) were synthesized and utilized as a sensing interface. The morphology, crystallinity, optical properties, chemical structures, and surface properties of immobilized AuNPs on the sensing electrodes were investigated. The sensing performance of the fabricated sensor was evaluated by using an electrochemical method to observe the current changes in cyclic voltammetric responses. The CHI-AuNP-TSC electrode has higher sensitivity toward E. coli than CHI-AuNP with a limit of detection (LOD) of 1.07 CFU/mL. TSC in the AuNPs synthesis process played a vital role in the particle size, the interparticle spacing, the sensor's effective surface area, and the presence of CHI around AuNPs, thus enhancing the sensing performance. Moreover, post-analysis of the fabricated sensor surface exhibited the sensor stability and the interaction between bacteria and the sensor surface. The sensing results showed a promising potential for rapid detection using a portable sensor for various water and food-borne pathogenic diseases.

17.
Cureus ; 15(5): e39266, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37342755

RESUMO

CONTEXT: The association between epilepsy control and the duration of sleep among people with epilepsy (PWE) is not well studied in Middle Eastern countries such as Oman. AIMS: To describe the sleep habits of PWE in Oman and explore the association of their sleep habits at night and afternoon siesta with the level of seizure control achieved and antiseizure medications (ASMs) consumed. METHODS: The subjects of this cross-sectional study were adult epilepsy patients attending a neurology clinic. Their sleep parameters were measured for one week using actigraphy. Home sleep apnea testing for one night was conducted to rule out obstructive sleep apnea (OSA). RESULTS: A total of 129 PWE completed the study. Their mean age was 29.8 ±â€¯9.2  years, and their mean body mass index (BMI) was 27.1 kg/m2. There was no significant difference between the people with controlled and uncontrolled epilepsy as regards the duration of night sleep or afternoon siesta (p = 0.24 and 0.37, respectively). There was also no significant correlation between their nighttime sleep duration, afternoon siesta, and the number of ASMs they consumed (p = 0.402 and 0.717, respectively). CONCLUSION: The study revealed that the sleep habits of PWE with uncontrolled epilepsy who consumed more ASMs were not significantly different from those with controlled epilepsy who consumed fewer ASMs.

18.
Front Public Health ; 11: 1115531, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304098

RESUMO

Background: Despite the importance of organ donation and transplantation in improving the quality of life, still, there is a shortage of organ donations, worldwide. Lack of knowledge among the public could be the reason. In previous studies, the focus was predominantly on medical students at universities. The aim of this study was to assess university students' knowledge and attitude about organ donation and transplantation among different colleges at the university. Method: A cross-sectional study was conducted among university students between August 2021 and February 2022 using a validated self-designed questionnaire. The questionnaire consisted of five sections. The first section was about the research information. The second section was informed consent. The third section was about sociodemographic information. The fourth section was about the knowledge of organ donation. The last section was about the attitude toward organ donation. The data were analyzed by descriptive statistics and chi-square tests. Results: The study included 2,125 students. 68.1% were females, and 93.1% were in the age group 17-24 years old. Only 34.1% had good knowledge about organ donation, 70.2% had a low attitude, and 7.53% had adequate information about brain death. The most common reason for supporting donating organs among university students was to save a life (76.8%) and the most common reason for refusing organs, was I am still unaware. In addition, only 25.66% of the participants had a high attitude toward people with poor knowledge about organ donation. The majority of the students (84.13%) used online sources and social networks as the primary sources of information about organ donation. Conclusion: The knowledge and attitudes of university students toward organ donation and transplantation were low. Saving a life was the most common reason for supporting organ donation, and knowledge was the biggest obstacle. Online sources and social networks were the primary sources of knowledge. The attitude was greatly influenced by knowledge. Organizing campaigns, and events, and incorporating organ donation and transplantation into university curricula will increase university students' knowledge and attitudes.


Assuntos
Estudantes de Medicina , Obtenção de Tecidos e Órgãos , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Masculino , Estudos Transversais , Qualidade de Vida , Universidades , Atitude
19.
PLoS One ; 18(8): e0279612, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37549148

RESUMO

BACKGROUND: Existing literature that examines the Hikikomori-like idiom of distress (HLID) initially labelled this phenomenon as a culture-bound syndrome. However, the increasing number of reports from other parts of the world suggest that HLID could instead be a culture-reactive idiom of distress, originating from biopsychosocial disequilibrium and cultural upheaval. The impact of imposed social withdrawal due to the Coronavirus 2 severe acute respiratory syndrome (SARS-CoV-2) pandemic on the growing prevalence of HLID has not yet been adequately explored. Aims: The first objective is to examine the factorial validity of the 25-item Hikikomori Questionnaire (HQ-25) in Oman. Second, we aimed to investigate the prevalence of HLID following the lifting of SARS-COV-2 restrictions in the Arabian Gulf country of Oman. The third related objective is to examine factors associated with the variation of HLID. METHODS: This cross-sectional online survey was widely distributed across the diverse socio-demographic population residing in Oman. After the validation of the questionnaire and the factorial validity, the Arabic version of HQ-25 was used to explore the prevalence and factors associated with HLID. RESULTS: A total of 1529 participants were included in the study (response rate = 76.5%), of whom 44% (n = 673) expressed HLID. We randomly split it into half, one for exploratory factor analysis (EFA) (n = 764) and the other half for confirmatory factor analysis (CFA) (n = 765). From the EFA results, a three-factor model was found for the Omani version of HQ-25, which represented 52.87% of the variance with good internal reliability (Overall Cronbach's: 0.92; Socialisation: 0.92; Isolation: 0.84; Emotional support: 0.73). The CFA results report acceptable goodness-of-fit indices (χ2/df = 17.92, p < .001; CFI = 0.90; TLI = 0.95; RMSEA = 0.04, 95% CI 0.02-0.07; SRMR = 0.05) of the three-factor model of the collected samples. All 1529 data were used in the respondents. The results of the logistic regression showed that married marital status (OR = 1.51, 95% CI: 1.12-2.03, p = 0.007), older age (OR = 0.97, 95% CI: 0.95-0.99, p = 0.008), living in an urban area (OR = 0.71, 95% CI: 0.56-0.91, p = 0.006), unemployed occupational status (OR = 1.72, 95% CI: 1.30-2.88, p < .001), screen time (7+ hours vs. <4 hours: OR = 4.50, 95% CI: 3.16-6.41, p < .001; 4-7 hours vs. <4 hours: OR = 2.10, 95% CI: 1.61-2.70, p < .001), history of mental illness (OR = 3.70, 95% CI: 2.29-5.91, p < .001), and adverse childhood experiences (OR = 2.60, 95% CI: 2.03-3.20, p < .001) were significant risk factors for HLID. CONCLUSION: The factorial validity of the HQ-25 performed in this study appears to mirror the previously reported 3-factor structures. Some of the associated factors appear to support and, conversely, dissent from the findings of previous studies. These are discussed in terms of the attributions of the SARS-COV-2 pandemic, demographic trends in Oman, and sociocultural factors specific to the region of interest.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Omã/epidemiologia , Reprodutibilidade dos Testes , Estudos Transversais , Pandemias , Prevalência , COVID-19/epidemiologia , Inquéritos e Questionários , Psicometria
20.
Front Psychiatry ; 13: 869464, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299550

RESUMO

Introduction: Sleep has different patterns followed worldwide and can be influenced by social, cultural, and environmental factors. Daytime napping is commonly practiced in different parts of the world with controversial results of its effect on glucose metabolism. The current study aims to examine the association of afternoon napping and night sleep duration with metabolic derangements. Methods: This is a cross-sectional study involving young adults and middle-aged subjects. Anthropometric measurements were taken for height and weight and hip and waist ratio. Consented subjects were asked to wear actigraphy for 1 week and run their usual daily activities. Home sleep apnea testing was performed to exclude obstructive sleep apnea. Subjects had been asked to come fasting on day seven for blood collection to test for fasting glucose, glycated hemoglobin, lipid profile, and insulin. Results: A total of 405 subjects were involved to complete the study (52% male, 48% female). The mean age of participants was 32.8 ± 11.5 years. The study indicated that the duration of afternoon napping was significantly associated with abnormal glycated hemoglobin (HbA1c > 5.7%) (p = 0.01) and body mass index (p = 0.046) independent of age, gender, and nocturnal sleep duration. Nocturnal sleep duration was associated with increased insulin level (p = 0.04). Conclusion: Afternoon napping is associated with an increased level of glycated hemoglobin and obesity and that may predispose to the development of type 2 diabetes mellitus.

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