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2.
Heliyon ; 9(10): e20842, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37886771

RESUMO

This study aimed to develop reference curves of aerobic parameters of 20 m shuttle run test for Tunisian soccer players. The study was conducted in the 2022/2023 pre-season. The reference curves of the maximal aerobic speed (MAS) and the maximal oxygen uptake (VO2max) were developed according to the Lambda, Mu and Sigma (LMS) method, using data from 742 Tunisian premier league soccer players aged 11-18 years. Measured variables included: weight, height, body mass index and maximal heart rate (HRmax). HRmax was measured when the participants completed the maximal aerobic speed. VO2max was estimated using the 20 m shuttle run test protocol (speed increment every minute). Our results presented the smoothed percentiles (3rd, 10th, 25th, 50th, 75th, 90th and 97th) of MAS (km/h) and VO2max (ml/kg•min⁻1) according to age. In addition, raw data showed that VO2 max was positively correlated with age (r = 0.333; P < 0.001), height (cm) (r = 0.279; P < 0.001), weight (kg) (r = 0.266; P < 0.001), practice period (years) (r = 0.324; P < 0.001) and BMI (kg/m2) (r = 0.10; P < 0.05). However, it was negatively correlated to HRmax (bpm) (r = -0.247; P < 0.001). Only the measurements within the age group [12-12.99] are significantly higher (p < 0.001; ES = 0.63) compared with the previous age group [11-11.99]. Finally, regarding prevalence, our findings showed that 15.5 % of the players in our sample had VO2max values above the 87.7th percentile cut-off, while only 0.3 % exceeded the 99.18th percentile. The development of normative curves could help coaches and physical trainers to more accurately detect weaknesses in the aerobic performance of their players in order to sustain high-intensity repetitive actions during a soccer match.

4.
Psychol Res Behav Manag ; 16: 2383-2394, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37408785

RESUMO

Purpose: Nomophobia refers to a psychological state in which individuals experience anxiety or fear at the thought of being disconnected from their mobile phone. The Nomophobia Questionnaire was developed to assess dimensions of nomophobia among native English-speaking populations. The purpose of this study was to adapt and validate the Nomophobia Questionnaire in the Tunisian context based on Western Arabic dialects. Methods: This cross-sectional design using a non-probability sampling method was conducted from September 05 to October 06, 2022. A total of 644 participants, with an average age of 21.04 ± 1.59 years, completed a sociodemographic questionnaire and an Arabic version of the Nomophobia Questionnaire. Participants were divided into two groups to perform exploratory and confirmatory factor analysis. The first group consisted of 200 students (56% female and 44% male with an average age of 21.10 ± 1.64), with 33% (n = 66) freshmen, 41.5% second-year students (n = 83) and 25.5% (n = 51) of third-year students. The second group was collected one month later in the same establishment and was composed of 444 students (52% men and 48% female with an average age of 21.01 ± 1.57). Results: The results of the exploratory and confirmatory factor analysis showed that the 20 items and the second order four-factor structure should be retained. Confirmatory factor analysis of the Arabic version of the NMP-Q gave the following statistics: χ2/df= 1.47; Fit Index = 0.997; Adjusted goodness-of-fit index = 0.996; Tucker-Lewis index = 1.003; Comparative Fit Index = 1; Root mean square error of approximation = 0.000 (90% CI 0-0) and standardized mean residual = 0.030, indicating good model fit. McDonald's ω internal consistency indexes for the four factors, namely giving up convenience, not being able to access information, not being able to communicate, and losing connectedness were 0.821, 0.841, 0.851, and 0.897, respectively. These values demonstrated good scale consistency. Conclusion: The Arabic Version of the Nomophobia questionnaire has been found to be a reliable and valid psychometric tool, and can be effectively used to measure nomophobia in countries where western Arabic dialects are spoken.

5.
JMIR Form Res ; 7: e42584, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36482747

RESUMO

BACKGROUND: Nowadays, digital gaming occupies a central position in the entertainment industry where it has developed into a cherished kind of entertainment in markets all over the world. In addition, it provides other sectors with various social and economic benefits. The Game Experience Questionnaire (GEQ) is a free, quantitative, and comprehensive self-report measure that was developed to assess the player game experience. Despite having been widely used by many research projects in the past, it has not been adapted into Arabic. Furthermore, several components of the scale proved problematic from a psychometric point of view. Therefore, a modified version of the scale is needed to measure the gaming experience of the Arab population. OBJECTIVE: The aim of this study was to validate and examine the psychometrics of an adapted Arabic version of the GEQ in Tunisia. METHODS: A total of 771 volunteer participants completed an online survey, which included an Arabic version of the GEQ, gaming data, and a sociodemographic questionnaire. Subjects were randomized in order to complete two phases of the study: exploratory and confirmatory. The exploratory data were acquired from 360 respondents whose mean age was 23.89 (SD 2.29) years. Out of 360 respondents, 111 (30.8%) were female and 249 (69.2%) were male. Confirmatory data were obtained from the remaining 411 subjects whose mean age was 21.94 (SD 1.80) years. Out of 411 subjects, 169 (41.1%) were female and 242 (58.9%) were male. RESULTS: After the elimination of two items, the exploratory and the confirmatory factor analyses provided an adequate factor structure of the Arabic version of the GEQ. In addition, the internal consistency coefficients suggested the reliability of the instrument. Significant differences were revealed for three subcomponents: flow by age (η2=0.013, P=.002), gender (η2=0.007, P=.02), and game type (η2=0.03, P<.001). For competence (η2=0.01, P=.03) and immersion (η2=0.02, P=.01), significant differences were highlighted by the type of game. The discriminant and convergent validities of the instrument were supported by calculating the average variance extracted (AVE) and comparing the square roots of the AVE values to the correlation coefficients, respectively. CONCLUSIONS: The Arabic adapted version of the GEQ is valid and reliable and can be administered to measure the game experience in Arab countries.

6.
Nat Prod Res ; 37(1): 136-140, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34498958

RESUMO

The present study has tentatively elucidated the structure of two acylated polyoxypregnane glycosides from Caralluma quadrangula (Forssk.) N.E.Br. (CQ). The analyses were performed using an electrospray-ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometer in positive ionization modes to explore fragmentation pathways. The used ionization mode provided consistent and/or complementary information for most of the pregnane glycosides, their fragmentation sequences, and their aglycones. Presumably, this is due to higher efficiency, sensitivity, and better selectivity of the mass spectrometry-based method. The present experimental and theoretical report deals with the characteristic fragmentation behaviors of two acylated polyoxypregnane glycosides CQ1 and CQ2 from the aerial parts of C. quadrangular. A DFT Study was performed to elucidate the position of ikemoyl, and benzoyl residues in compounds CQ1 and CQ2, respectively.


Assuntos
Apocynaceae , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Glicosídeos/química , Cromatografia Líquida de Alta Pressão/métodos
7.
Front Psychiatry ; 14: 1277756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239905

RESUMO

Background: Psychiatry is a specialized field of medicine that focuses on the diagnosis, treatment, and prevention of mental health disorders. With advancements in technology and the rise of artificial intelligence (AI), there has been a growing interest in exploring the potential of AI language models systems, such as Chat Generative Pre-training Transformer (ChatGPT), to assist in the field of psychiatry. Objective: Our study aimed to evaluates the effectiveness, reliability and safeness of ChatGPT in assisting patients with mental health problems, and to assess its potential as a collaborative tool for mental health professionals through a simulated interaction with three distinct imaginary patients. Methods: Three imaginary patient scenarios (cases A, B, and C) were created, representing different mental health problems. All three patients present with, and seek to eliminate, the same chief complaint (i.e., difficulty falling asleep and waking up frequently during the night in the last 2°weeks). ChatGPT was engaged as a virtual psychiatric assistant to provide responses and treatment recommendations. Results: In case A, the recommendations were relatively appropriate (albeit non-specific), and could potentially be beneficial for both users and clinicians. However, as complexity of clinical cases increased (cases B and C), the information and recommendations generated by ChatGPT became inappropriate, even dangerous; and the limitations of the program became more glaring. The main strengths of ChatGPT lie in its ability to provide quick responses to user queries and to simulate empathy. One notable limitation is ChatGPT inability to interact with users to collect further information relevant to the diagnosis and management of a patient's clinical condition. Another serious limitation is ChatGPT inability to use critical thinking and clinical judgment to drive patient's management. Conclusion: As for July 2023, ChatGPT failed to give the simple medical advice given certain clinical scenarios. This supports that the quality of ChatGPT-generated content is still far from being a guide for users and professionals to provide accurate mental health information. It remains, therefore, premature to conclude on the usefulness and safety of ChatGPT in mental health practice.

8.
Nanomaterials (Basel) ; 12(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36432231

RESUMO

Removing toxic metal ions arising from contaminated wastewaters caused by industrial effluents with a cost-effective method tackles a serious concern worldwide. The adsorption process onto metal oxide and carbon-based materials offers one of the most efficient technologies adopted for metal ion removal. In this study, mesoporous MgO/g-C3N4 sorbent is fabricated by ultrasonication method for the uptake Pb (II) and Cd (II) heavy metal ions from an aqueous solution. The optimum conditions for maximum uptake: initial concentration of metal ions 250 mg g-1, pH = 5 and pH = 3 for Pb++ and Cd++, and a 60 mg dose of adsorbent. In less than 50 min, the equilibrium is reached with a good adsorption capacity of 114 and 90 mg g-1 corresponding to Pb++ and Cd++, respectively. Moreover, the adsorption isotherm models fit well with the Langmuir isotherm, while the kinetics model fitting study manifest a perfect fit with the pseudo-second order. The as fabricated mesoporous MgO/g-C3N4 sorbent exhibit excellent Pb++ and Cd++ ions uptake and can be utilized as a potential adsorbent in wastewater purification.

9.
RSC Adv ; 12(38): 24786-24803, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36199891

RESUMO

Novel doped MgO nanoadsorbents were effectively fabricated at various Bi2O3 doping concentrations (0, 2.5, 5 and 10%). DFT-D3 study showed that the doping is done by substitution of two magnesium atoms by two bismuth atoms with the creation of a vacancy of one Mg atom. TEM, SEM, EDX, BET, XRD, and FTIR were used to characterize the obtained nanostructures. The removal of indigo carmine (IC) dyes from wastewater by doped MgO nanoparticles is investigated. Experimental parameters such as the initial dye concentration, contact time, Bi2O3 doping concentration, and pH were optimized to enhance the adsorption capacity. Bi2O3 doped MgO prepared at 5% (MgOBi2) is the best adsorbent with a maximum IC adsorption capacity of 126 mg g-1 at a solution pH equal to 7.00 and contact time of 74 min. The results indicated that the adsorption process followed pseudo-second-order (PSO) reaction kinetics, and the Freundlich isotherm model gave a better goodness-of-fit than the linear Langmuir model. The FTIR study established that IC molecules are successfully adsorbed onto the surface of MgOBi2 via a chemisorption process.

10.
Biomed Pharmacother ; 150: 112954, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35447547

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Caralluma quadrangula (Forssk.) N.E.Br. (Syns: = Stapelia quadrangula Forssk. = Monolluma quadrangula Forssk.) is an indigenous member of the genus Caralluma and it is a rather common species on rocky hillsides in the southwestern part of Saudi Arabia. Several members of this genus have found medicinal uses in the treatment of rheumatism, diabetes, leprosy and as antiseptics and disinfectants. All parts are edible but rather more bitter and can cause diarrhea. AIM OF THE STUDY: The present report was tentatively elucidated the structure of acylated and non-acylated polyoxypregnane glycosides from Caralluma quadrangula. MATERIALS AND METHODS: The analyses were performed using an electrospray-ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometer in both positive and negative ionization modes to explore fragmentation pathways. The antioxidant and prooxidant properties of the different mobility portions of human plasma were evaluated in vitro using thiobarbituric acid reactive substance assay (TBARS). RESULTS: The analyses showed sixty-five characteristic ion peaks which could be more efficient to assignment the aglycones and fragmentation sequences of sugar moieties. The used ionization modes provided consistent and/or complementary information for most of the pregnane glycosides, their fragmentation sequences, and their aglycones. A DFT Study was performed to elucidate the neutral loss of H2O molecules sequences from aglycones and the esterification linkage. CONCLUSIONS: This report could be useful to reduce material consuming and time in phytochemistry analysis of the different medicinal plants. The two portions significantly depleted TBARS were subjected to autoperoxidation assay in the presence of hydrogen peroxide.


Assuntos
Antioxidantes , Apocynaceae , Antioxidantes/farmacologia , Apocynaceae/química , Cromatografia Líquida de Alta Pressão , Glicosídeos/farmacologia , Humanos , Saponinas , Espectrometria de Massas por Ionização por Electrospray , Substâncias Reativas com Ácido Tiobarbitúrico
11.
Nanomaterials (Basel) ; 12(6)2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35335846

RESUMO

The organic synthetic dyes employed in industries are carcinogenic and harmful. Dyes must be removed from wastewater to limit or eliminate their presence before dumping into the natural environment. The current study aims to investigate the use of MgO nanoparticles to eliminate basic fuchsine (BF), as a model cationic dye pollutant, from wastewater. The MgO nanorods were synthesized through a coprecipitation method. The obtained nanocomposite was characterized using various techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Brunauer-Emmett-Teller (BET), and FTIR spectroscopy. It was found that the variation of dye concentration and pH influenced the removal of BF by MgO. The adsorption capacity of 493.90 mg/g is achieved under optimum operating conditions (pH = 11, contact time = 236 min, and initial BF concentration = 200 ppm). Pseudo-second-order adsorption kinetics and Freundlich isotherm models best fitted BF sorption onto MgO nanorods. The BF sorption mechanism is associated with the electrostatic attractions and hydrogen bond between the O-H group of MgO and the NH2 groups of BF, as indicated by the pH, isotherms, and FTIR studies. The reusability study indicates that MgO was effectively used to eliminate BF in at least four continuous cycles. The investigation of MgO with different dyes suggests the high adsorption selectivity of BF, crystal violet (CV), and malachite green (MG) dyes compared with methyl orange (MO) dye. Overall, MgO nanorods can act as a potential and promising adsorbent for the efficient and rapid removal of cationic dyes (CV, MG, and BF) from wastewater.

12.
Langmuir ; 37(24): 7285-7294, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34102848

RESUMO

Ba-loaded ZnO nanoparticles (Ba/ZnO) were obtained by the co-precipitation process and employed as a sorbent for Congo Red (C32H22N6Na2O6S2) dye (CR). Physicochemical parameters such as particle size, pH, and contact time were checked to characterize the adsorption process. The maximum adsorption capacity of Ba/ZnO NPs for CR (1614.26 mg/g) proves its potential utility in the elimination of CR dye from wastewater. The adsorption mechanism was studied via infrared spectroscopy and density functional theory calculations. The geometrical parameters and electronic properties of the CR-Ba/ZnO complex, particularly the interaction energy, the density of states, and the charge transfer, highlighted the Ba-ion mediation in the chemical bond formation between CR and the surface. The interaction between CR and Ba-doped ZnO has found to show strong chemisorption with charge transfer between the SO3- group and adsorbed Ba2+ ion on the surface.

13.
Nanoscale ; 7(7): 3189-95, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25615699

RESUMO

Here, we report a new synthetic route for spherical small copper nanoparticles (CuNPs) with size ranging from 3.5 nm to 11 nm and with an unprecedented associated monodispersity (<10%). This synthesis is based on the reduction of an organometallic precursor (CuCl(PPh3)3) by tert-butylamine borane in the presence of dodecylamine (DDA) at a moderate temperature (50 to 100 °C). Because of their narrow size distribution, the CuNPs form long-range 2D organizations (several µm(2)). The wide range of CuNPs sizes is obtained by controlling the reaction temperature and DDA-to-copper phosphine salt ratio during the synthesis process. The addition of oleic acid (OA) after the synthesis stabilizes the CuNPs (no coalescence) for several weeks under a nitrogen atmosphere. The nature and the reactivity of the ligands were studied by IR and UV-visible spectroscopy. We thus show that just after synthesis the nanoparticles are coated by phosphine and DDA. After adding OA, a clear exchange between phosphine and OA is evidenced. This exchange is possible thanks to an acid-base reaction between the free alkylamine in excess in the solution and OA. OA is then adsorbed on the NPs surface in the form of carboxylate. Furthermore, the use of oleylamine (OYA) instead of DDA as the capping agent allows one to obtain other NP shapes (nanorods, triangles and nanodisks). We get evidence that OYA allows the selective adsorption of chloride ions derived from the copper precursor on the different crystallographic faces during the growth of CuNPs that induces the formation of anisotropic shapes such nanorods or triangles.

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