1
|
Ahmed AB, Feki H, Abid Y, Boughzala H, Mlayah A. Structural, vibrational and theoretical studies of l-histidine bromide. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2007.11.056] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
|
17 |
64 |
2
|
Ahmed AB, Feki H, Abid Y, Boughzala H, Minot C, Mlayah A. Crystal structure, vibrational spectra and theoretical studies of l-histidinium dihydrogen phosphate-phosphoric acid. J Mol Struct 2009. [DOI: 10.1016/j.molstruc.2008.09.029] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
|
16 |
51 |
3
|
Dammak H, Feki H, Boughzala H, Abid Y. Crystal structure, vibrational spectra and non-linear optical properties of diethylenetriammonium hexabromobismuthate: C4H16N3BiBr6. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 137:1235-1243. [PMID: 25305616 DOI: 10.1016/j.saa.2014.08.150] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/26/2014] [Accepted: 08/31/2014] [Indexed: 06/04/2023]
Abstract
A new organic-inorganic material, diethylenetriammonium hexabromobismuthate (C4H16N3)BiBr6, was synthesized and characterized by X-ray diffraction, infrared absorption, Raman spectroscopy scattering and optical absorption. The crystal lattice is composed of discrete [BiBr6] anions surrounded by diethylenetriammonium cations. The title compound crystallizes in the non-centro-symmetric space group P212121 of orthorhombic system. Theoretical calculations were performed using density functional theory (DFT) at B3LYP/LanL2DZ level of theory for studying the molecular structure, vibrational spectra and non-linear optical (NLO) properties of the investigated molecule in the ground state. Good consistency is found between the calculated results and the experimental structure, IR, and Raman spectra. The results also show that the title compound might have important NLO behavior and can be a potential new nonlinear optical (NLO) material of interest.
Collapse
|
|
10 |
35 |
4
|
Ben Ahmed A, Feki H, Abid Y, Boughzala H, Minot C. Crystal studies, vibrational spectra and non-linear optical properties of L-histidine chloride monohydrate. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 75:293-298. [PMID: 19926520 DOI: 10.1016/j.saa.2009.10.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 10/03/2009] [Accepted: 10/13/2009] [Indexed: 05/28/2023]
Abstract
This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a non-linear optical material L-histidine chloride monohydrate. Due to the lack of sufficiently precise information on geometric parameters available in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine chloride monohydrate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro-symmetric space group P2(1)2(1)2(1) of orthorhombic system. IR spectrum has been recorded in the range [400-4000 cm(-1)]. All the experimental vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our calculations. The optimized geometric bond lengths and bond angles obtained by using DFT//B3LYP/6-31G (d) method show a good agreement with the experimental data. The calculated vibrational spectra are in well agreement with the experimental one. To investigate microscopic second-order non-linear optical NLO behavior of the examined complex, the electric dipole mu, the polarizability alpha and the hyperpolarizability beta were computed using DFT//B3LYP/6-31G (d) method. The time-dependent density functional theory (TD-DFT) was employed to descript the molecular electron structure of the title compound using the B3LYP/6-31G (d) method. According to our calculations, L-histidine chloride monohydrate exhibits non-zero beta value revealing microscopic second-order NLO behavior.
Collapse
|
|
15 |
31 |
5
|
Guidara S, Ahmed AB, Abid Y, Feki H. Molecular structure, vibrational spectra and nonlinear optical properties of 2,5-dimethylanilinium chloride monohydrate: a density functional theory approach. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 127:275-285. [PMID: 24632236 DOI: 10.1016/j.saa.2014.02.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 01/30/2014] [Accepted: 02/09/2014] [Indexed: 06/03/2023]
Abstract
Single crystals of 2,5-dimethylanilinim chloride monohydrate were grown by slow evaporation at room temperature and were characterized by X-ray powder diffraction study to confirm the crystalline nature of the synthesized compound. The optimized molecular structure, vibrational spectra and the optical properties were calculated by the density functional theory (DFT) method using the B3LYP function with the 6-31G(d,p) basis set. Simulation of infrared and Raman spectra led to excellent overall agreement with the observed spectral patterns. The complete assignments of the vibrational spectra were carried out with the aid of potential energy distribution (PED). The stability of the molecule arising from hyperconjugative interaction and charge delocalization has been analyzed using natural bond orbital (NBO) analysis leading to high nonlinear optical (NLO) activity. The lowering in the HOMO and LUMO energy gap explains the eventual charge transfer interactions that take place within the molecules.
Collapse
|
|
11 |
23 |
6
|
Elleuch N, Amamou W, Ben Ahmed A, Abid Y, Feki H. Vibrational spectroscopic study, charge transfer interaction and nonlinear optical properties of L-asparaginium picrate: a density functional theoretical approach. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 128:781-789. [PMID: 24704485 DOI: 10.1016/j.saa.2014.02.159] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 02/20/2014] [Accepted: 02/23/2014] [Indexed: 06/03/2023]
Abstract
Single crystals of L-asparaginium picrate (LASP) were grown by slow evaporation technique at room temperature and were the subject of an X-ray powder diffraction study to confirm the crystalline nature of the synthesized compound. FT-IR and Raman spectra were recorded and analyzed with the aid of the density functional theory (DFT) calculations in order to make a suitable assignment of the observed bands. The optimum molecular geometry, normal mode wavenumbers, infrared and Raman intensities and the first hyperpolarizability were investigated with the help of B3LYP method using 6-31G(d) basis set. The theoretical FT-IR and Raman spectra of LASP were simulated and compared with the experimental data. A good agreement was shown and a reliable vibrational assignment was made. Natural bond orbital (NBO) analysis was carried out to demonstrate the various inter and intramolecular interactions that are responsible for the stabilization of the title compound leading to high NLO activity. A study on the electronic properties was performed by time-dependent DFT (TD-DFT) approach. The lowering in the HOMO and LUMO energy gap explains the eventual charge transfer interactions that take place within the molecules.
Collapse
|
|
11 |
20 |
7
|
Amamou W, Feki H, Chniba-Boudjada N, Zouari F. Synthesis, crystal structure, vibrational properties and theoretical investigation of (N,N-dimethylbenzylammonium)trichlorocadmate(II). J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2013.11.053] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
|
11 |
19 |
8
|
Ben Ahmed A, Elleuch N, Feki H, Abid Y, Minot C. Vibrational spectra and non linear optical proprieties of L-histidine oxalate: DFT studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:554-561. [PMID: 21530379 DOI: 10.1016/j.saa.2011.03.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 02/28/2011] [Accepted: 03/11/2011] [Indexed: 05/30/2023]
Abstract
This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a nonlinear optical material L-histidine oxalate. Due to the lack of sufficiently precise information on geometric structure in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine oxalate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro symmetric space group P2(1)2(1)2(1) of orthorhombic system. The FT-IR and Raman spectra of L-histidine oxalate were recorded and analyzed. The vibrational wave numbers were examined theoretical with the aid of Gaussian98 package of programs using the DFT//B3LYP/6-31G(d) level of theory. The data obtained from vibrational wave number calculations are used to assign vibrational bands obtained in IR and Raman spectroscopy of the studied compound. The geometrical parameters of the title compound are in agreement with the values of similar structures. To investigate microscopic second order non-linear optical NLO behaviour of the examined complex, the electric dipole μ(tot), the polarizability α(tot) and the hyperpolarizability β(tot) were computed using DFT//B3LYP/6-31G(d) method. According to our calculation, the title compound exhibits non-zero β(tot) value revealing microscopic second order NLO behaviour.
Collapse
|
|
14 |
19 |
9
|
Guidara S, Feki H, Abid Y. Vibrational spectral studies and non-linear optical properties of L-leucine L-leucinium picrate: a Density Functional Theory approach. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 115:437-444. [PMID: 23867646 DOI: 10.1016/j.saa.2013.06.080] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 06/11/2013] [Accepted: 06/19/2013] [Indexed: 06/02/2023]
Abstract
Single crystals of l-leucine l-leucinium picrate were grown by slow evaporation at room temperature and were characterized by X-ray powder diffraction study to confirm the crystalline nature of the synthesized compound. The optimized molecular structure, vibrational spectra and the optical properties were calculated by the Density Functional Theory (DFT) method using the B3LYP function with the 6-31G(d) basis set. Good consistency is found between the calculated results and the experimental structure, IR, and Raman spectra. The detailed interpretation of the vibrational modes was carried out. The natural bond orbital (NBO) analysis, confirms the occurrence of intermolecular hydrogen bonds that are responsible for the stabilization of the title compound, leading to high nonlinear optical (NLO) activity. The lowering in the HOMO and LUMO energy gap explains the eventual charge transfer interactions that take place within the molecules.
Collapse
|
|
12 |
16 |
10
|
Elleuch S, Feki H, Abid Y. HF, MP2 and DFT calculations and spectroscopic study of the vibrational and conformational properties of N-diethylendiamine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 68:942-7. [PMID: 17317286 DOI: 10.1016/j.saa.2007.01.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Accepted: 01/13/2007] [Indexed: 05/14/2023]
Abstract
The conformational stability and vibrational modes of the N-diethylendiamine organic cation (N-DD(2+)) were studied by experimental (Raman) spectroscopy combined with theoretical calculations. Various ab initio theories were used: Hartree-Fock (HF) theory, Möller-Plesset second-order perturbation (MP2) theory and density functional theory (DFT). Three stable conformers of N-DD(2+), trans-trans, gauche-gauche and gauche-trans were calculated. A comparison between the computed structural parameters of the conformers at both levels of theory and the X-ray data was made. It is demonstrated that the N-DD(2+) cation adopts more probably the gauche-gauche conformation at room temperature. In order to make a more detailed interpretation of the low temperature phase transition of N-DDHP, the Raman spectra of N-DDHP were recorded at room and low temperature in the 200-3400 cm(-1) region. The vibrational frequencies of the different conformers of N-DD(2+) were also calculated using the DFT/B3LYP (6-31G(d)) level of theory. By comparison between the experimental and theoretical results, the conformational dynamic of the N-DD(2+) organic cation was confirmed. It is shown that the N-DD(2+) cation configuration changes from gauche-gauche conformer to gauche-trans conformer when decreasing the temperature.
Collapse
|
|
18 |
14 |
11
|
Amamou W, Elleuch N, Feki H, Chniba-boudjada N, Zouari F. Structural characterization, thermal studies, vibrational and DFT investigation of the bis(8-hydroxyquinolinium)tetrachlorocadmate(II). J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2014.11.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
|
10 |
14 |
12
|
Guidara S, Feki H, Abid Y. Molecular structure, NLO, MEP, NBO analysis and spectroscopic characterization of 2,5-dimethylanilinium dihydrogen phosphate with experimental (FT-IR and FT-Raman) techniques and DFT calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 133:856-866. [PMID: 25014546 DOI: 10.1016/j.saa.2014.06.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/20/2014] [Accepted: 06/03/2014] [Indexed: 06/03/2023]
Abstract
Single crystals of 2,5-dimethylanilinium dihydrogen phosphate were grown by slow evaporation method at room temperature. The synthesized compound was characterized by powder X-ray diffraction analysis to confirm its crystalline nature. The optimized molecular structure, vibrational spectra and the optical properties were calculated by the density functional theory (DFT) method using the B3LYP function with the 6-31G(d,p) basis set. Theoretical simulation of infrared and Raman spectra led to excellent overall agreement with the observed spectral patterns. The complete assignments of the vibrational spectra were carried out with the aid of potential energy distribution (PED). The stability of the molecule arising from hyperconjugative interaction and charge delocalization has been analyzed using natural bond orbital (NBO) analysis leading to high nonlinear optical (NLO) activity. The lowering in the HOMO and LUMO energy gap explains the eventual charge transfer interactions that take place within the molecules.
Collapse
|
|
11 |
14 |
13
|
Ghroubi S, Chaari M, Elleuch H, Massmoudi K, Abdenadher M, Trabelssi I, Akrout M, Feki H, Frikha I, Dammak J, Kammoun S, Zouari N, Elleuch MH. The isokinetic assessment of peripheral muscle function in patients with coronary artery disease: correlations with cardiorespiratory capacity. ACTA ACUST UNITED AC 2007; 50:295-301; 287-94. [PMID: 17449129 DOI: 10.1016/j.annrmp.2007.03.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Accepted: 03/08/2007] [Indexed: 11/15/2022]
Abstract
OBJECTIVE We aimed to determine whether diminished cardiorespiratory capacity in patients with coronary artery disease (CAD) is accompanied by impaired skeletal muscle function as measured by isokinetic dynamometry. We also evaluated the correlation between isokinetic strength and aerobic capacity in these patients. MATERIALS AND METHODS Fifteen CAD patients and 15 age-matched healthy subjects (mean age 60+/-6 vs. 57+/-3.5 years) underwent maximal laboratory exercise testing, a 6-min walking test and an assessment of peripheral skeletal muscle function by use of an isokinetic apparatus. Quadricep and hamstring function was tested at two angular velocities, 150 and 180 degrees s(-1) with simultaneous electrocardiography monitoring. The cardiorespiratory and mechanical parameters (VO(2), ventilatory threshold [VT], heart rate [HR], and power) were measured at VT and at maximal effort. RESULTS Quadricep and hamstring peak torque was impaired in CAD patients, with quadriceps peak torque at 180 degrees being 71.13 +/- 14 vs. 91.13 +/- 23 Nm (P<0.01) and hamstring peak torque 46.50+/-10 vs. 59.86+/-12 Nm (P<0.01). CAD subjects presented a deficient aerobic capacity as compared with the healthy subjects at maximal effort. At VT, the VO(2), ventilation, and HR were significantly lower in CAD patients, at 13.77+/-2.33 vs. 17.08+/-3.59 ml min(-1) kg(-1) (P<0.05), 29.64 +/- 664 vs. 37.76 +/- 7.2 ml min(-1) (P<0.05), and 86+/-14 vs. 111+/-15 beats min(-1) (P=0.001), respectively. The 6-min walking distance was significantly shorter for CAD patients than healthy subjects (425.93+/-52.77 vs. 551.46 +/- 57.94 m; P<0.01). In CAD patients quadriceps and hamstring strength was not correlated with VO(2) at maximal effort and at VT. Total distance walked during the 6-min walk and VO(2)max were correlated (r=0.869; P<0.001) but not at VT. CONCLUSION CAD patients showed impaired cardiorespiratory capacity accompanied by increased muscle fatigability as compared with healthy subjects. An isokinetic muscle assessment in these patients must be achieved systematically and seems to have value in cardiovascular rehabilitation.
Collapse
|
Journal Article |
18 |
13 |
14
|
Baklouti Y, chaari N, Feki H, Chniba-Boudjada N, Zouari F. Crystal structure, vibrational studies, optical properties and DFT calculations of 2-amino-5-diethyl-aminopentanium tetrachlorocadmate (II). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 136 Pt B:397-404. [PMID: 25311521 DOI: 10.1016/j.saa.2014.09.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 09/02/2014] [Accepted: 09/18/2014] [Indexed: 06/04/2023]
Abstract
Single crystals of a new organic-inorganic compound (C9H24N2) CdCl4 were grown by the slow evaporation technique and characterized by X-ray diffraction, infrared absorption Raman spectroscopy scattering, optical absorption, differential scanning calorimetry (DSC) analysis and dielectric measurements. The title compound belongs to the orthorhombic space group Pbca with the following unit cell parameters: a=11.397(7), b=13.843(4), c=22.678(5)Å and Z=8. In crystal structure, the tetrachlorocadmate anion is connected to organic cations through N-H⋯Cl hydrogen bonds. Theoretical calculations were performed using density functional theory (DFT) with the B3LYP/LanL2DZ level of theory for studying the molecular structure and vibrational spectra of the title compound. Good consistency is found between the calculated results and the experimental structure, IR, and Raman spectra. The detailed interpretation of the vibrational modes was carried out on the basis on our DFT calculations as primary source of assignment and by comparison with spectroscopic studies of similar compounds. The optical properties were investigated by optical absorption and show three bands at 300, 329 and 513 nm.
Collapse
|
|
10 |
13 |
15
|
Dhouib I, Feki H, Guionneau P, Mhiri T, Elaoud Z. Structural, vibrational and thermal studies of a new nonlinear optical crystal tetrapropylammonium dihydrogenmonoarsenate bis arsenic acid. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 131:274-281. [PMID: 24835929 DOI: 10.1016/j.saa.2014.04.120] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/15/2014] [Accepted: 04/22/2014] [Indexed: 06/03/2023]
Abstract
Single crystals of tetrapropylammonium dihydrogenmonoarsenate bis arsenic acid [CH3CH2CH2]4N (H2AsO4) (H3AsO4)2, a potential new nonlinear optical (NLO) material of interest were prepared by the slow evaporation technique and characterized by means of single-crystal X-ray diffraction, thermal analysis, FT-IR and Raman spectroscopy. The title compound belongs to the monoclinic space group Ia with the following unit cell dimensions: a=8.116(2) Ǻ, b=33.673(4) Ǻ, c=8.689(2) Ǻ, β=95.34(2)°. The structure consists of infinite parallel two-dimensional planes built of mutually [H2AsO4(-)] and [H3AsO4] tetrahedra connected by strong O-H⋯O hydrogen bonding giving birth to trimmers. The planes of inorganic groups are alternated with those of the organic cations. The geometry, first hyperpolarizability and harmonic vibrational wavenumbers were calculated by means of density functional theory DFT with the B3LYP/6-31G(d) level of theory. Good consistency was found between the calculated results and the experimental structure, IR, and Raman spectra. The detailed interpretation of the vibrational modes was carried out building on the proposed DFT calculations as primary source of assignment and by comparison with the spectroscopic studies of similar compounds. The first hyperpolarizability βtot of the title compound is about 14.6 times more than that of the reference crystal KDP, which may explain the importance of the compound under study.
Collapse
|
|
11 |
12 |
16
|
Elleuch N, Ben Ahmed A, Feki H, Abid Y, Minot C. Vibrational spectra, optical properties, NBO and HOMO-LUMO analysis of L-Phenylalanine L-Phenylalaninium Perchlorate: DFT calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 121:129-138. [PMID: 24231749 DOI: 10.1016/j.saa.2013.10.039] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 10/04/2013] [Accepted: 10/09/2013] [Indexed: 06/02/2023]
Abstract
In this work, we report a combined experimental and theoretical study of a nonlinear optical material, L-Phenylalanine L-Phenylalaninium Perchlorate. Single crystals of the title compound have been grown by slow evaporation of an aqueous solution at room temperature. Theoretical calculations were preceded by redetermination of the crystal X-ray structure. The compound crystallizes in the non-centro symmetric space group P2(1)2(1)2(1) of the orthorhombic system. The FT-IR and Raman spectra of the crystal were recorded and analyzed. The density functional theory (DFT) computations have been performed at B3LYP/6-31G(d) level to derive equilibrium geometry, vibrational wavenumbers, intensity and NLO properties. All observed vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our DFT calculations as a primary source of attribution and also by comparison with the previous results for similar compounds. Natural bond orbital analysis was carried out to demonstrate the various inter-and intramolecular interaction that are responsible of the stabilization of the compound. The lowering of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy gap appears to be the cause of its enhanced charge transfer interaction leading to high NLO activity.
Collapse
|
|
12 |
12 |
17
|
Ayed HB, Yaich S, Trigui M, Jemaa MB, Hmida MB, Karray R, Kassis M, Mejdoub Y, Feki H, Jedidi J, Damak J. Prevalence and risk factors of health care-associated infections in a limited resources country: A cross-sectional study. Am J Infect Control 2019; 47:945-950. [PMID: 30777390 DOI: 10.1016/j.ajic.2019.01.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 01/17/2019] [Accepted: 01/18/2019] [Indexed: 01/03/2023]
Abstract
BACKGROUND The aim of this study was to determine the prevalence of health care-associated infections (HAI) in our university hospitals (UH) and to delineate the risk factors associated with HAI. METHODS We conducted a cross-sectional study in the 2 UH of Sfax, Tunisia on July 2017, including all patients hospitalized for at least 48 hours. It was a 1-day pass per department and a 1-week prevalence survey per UH. RESULTS Of 752 patients eligible for the study, the total number of HAI was 82, representing an overall prevalence of HAI of 10.9%. Respiratory tract infections were the most prevalent HAI (36.6%). In multivariate analysis, intrinsic risk factors independently associated with HAI were immune-suppression (adjusted odds ratio (AOR) = 2.8; P < .001), diabetes (AOR = 2.2; P = .008), and malnutrition (AOR = 2.2; P = .019). Extrinsic risk factors were endotracheal intubation (AOR = 17; P = .01), transfer to another department (AOR = 9; P = .019), parental feeding (AOR = 7.2; P = .014), tobacco use (AOR = 6.3; P = .004), as well as surgical wound class contaminated or dirty (AOR = 6.3; P = .002), and peripheral venous catheter (AOR = 4.7; P = .006). CONCLUSIONS Our study highlighted the magnitude of the HAI problem threatening the quality of care in Southern Tunisia. A wise identification of HAI risk factors may help health care workers to ascertain the avoidability of these infections.
Collapse
|
|
6 |
11 |
18
|
Mezghani-Masmoudi M, Guermazi M, Feki H, Ennaouai A, Dammak J, Elleuch MH. Facteurs liés à l’avenir fonctionnel et professionnel des amputés des membres inférieurs appareillés. ACTA ACUST UNITED AC 2004; 47:114-8. [PMID: 15059674 DOI: 10.1016/j.annrmp.2003.12.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2003] [Accepted: 12/07/2003] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The objective of our study is to evaluate the functional and professional becoming of lower limb amputated population with prosthesis. MATERIAL AND METHODS Our study is retro-prospective. It interested lower limbs amputated patients who have beneficed during the period between 1982-1998 with prosthesis and have consulted in 1999. Data of our study were gathered by an hetero questionnaire. In order to evaluate the functional results of our patients, we have adopted the score established by the National association of doctors specialized in apparatus in France (ANMA). However, this score was little modified (in fact, we have eliminated the item "use of personalized vehicle for handicapped [VHP]", because no one of our patients possess it). The results were judged favourable: score 6-7; unfavourable: mean score between 3-5 and bad between 0-2. RESULTS During the year of our survey, we have questioned 85 lower limb amputated patients with prosthesis: 67 were male and 18 were female. The mean age of our patients is 48 years (6 to 86 years). Our population was divided into: 31 traumatic amputated, 28 arteritics and 26 amputated of other etiologies (tumoral, infectious, congenital...). In 76 cases, the amputation is unilateral. It's located upper the knee in 51 cases. The evaluation of functional autonomy of our patients according to score adopted showed those results: 54.11% were favourable and 45.88% were unfavourable. In professional side, only 35 among our 60 active patients before amputation, have been able to resume, 12 have needed a professional rehabilitation. Among the 25 who hadn't taken up again their work, 15 have early retirement and ten are in unemployment. CONCLUSION The amputation of lower limb constitute a major handicap which involves a functional and professional incapacity. We can reduce the risk of this incapacity by a good and appropriate rehabilitation.
Collapse
|
|
21 |
11 |
19
|
Ben Ahmed A, Feki H, Abid Y. Synthesis, crystal structure, vibrational spectroscopy, optical properties and theoretical studies of a new organic-inorganic hybrid material: [((CH3)2NH2)(+)]6·[(BiBr6)(3-)]2. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 133:357-364. [PMID: 24967541 DOI: 10.1016/j.saa.2014.05.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/14/2014] [Accepted: 05/28/2014] [Indexed: 06/03/2023]
Abstract
A new organic-inorganic hybrid material, [((CH3)2NH2)(+)]6·[(BiBr6)(3-)]2, has been synthesized and characterized by X-ray diffraction, FT-IR, Raman spectroscopy and UV-Visible absorption. The studied compound crystallizes in the triclinic system, space group P1¯ with the following parameters: a=8.4749(6)(Å), b=17.1392(12)(Å), c=17.1392(12)(Å), α=117.339(0)°, β=99.487(0)°, γ=99.487(0)° and Z=2. The crystal lattice is composed of a two discrete (BiBr6)(3-) anions surrounded by six ((CH3)2NH2)(+) cations. Complex hydrogen bonding interactions between (BiBr6)(3-) and organic cations from a three-dimensional network. Theoretical calculations were performed using density functional theory (DFT) for studying the molecular structure, vibrational spectra and optical properties of the investigated molecule in the ground state. The full geometry optimization of designed system is performed using DFT method at B3LYP/LanL2DZ level of theory using the Gaussian03. The optimized geometrical parameters obtained by DFT calculations are in good agreement with single crystal XRD data. The vibrational spectral data obtained from FT-IR and Raman spectra are assigned based on the results of the theoretical calculations. The energy and oscillator strength calculated by Time-Dependent Density Functional Theory (TD-DFT) results complements with the experimental findings. The simulated spectra satisfactorily coincide with the experimental UV-Visible spectrum. The results show good consistent with the experiment and confirm the contribution of metal orbital to the HOMO-LUMO boundary.
Collapse
|
|
11 |
11 |
20
|
Ben Ayed H, Yaich S, Ben Jemaa M, Ben Hmida M, Trigui M, Jedidi J, Sboui I, Karray R, Feki H, Mejdoub Y, Kassis M, Damak J. What are the correlates of body image distortion and dissatisfaction among school-adolescents? Int J Adolesc Med Health 2019; 33:/j/ijamh.ahead-of-print/ijamh-2018-0279/ijamh-2018-0279.xml. [PMID: 31100056 DOI: 10.1515/ijamh-2018-0279] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 01/02/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Body image is considered as central to many aspects of human functioning including emotions, thoughts, behaviors and relationships. Our study aimed to investigate the prevalence of body image distortion and dissatisfaction among adolescents and to assess their main determinants. METHODS This was a cross-sectional school-based study conducted among school-adolescents in the south of Tunisia, between October 2017 and February 2018. RESULTS Among 1210 school-adolescents, body image distortion and dissatisfaction prevalence were 44.8% and 42.4%, respectively. Multivariate analysis showed that being in the 16-18 years age group [adjusted odds ratio (AOR) = 1.28, p = 0.046], low family financial situation (AOR = 1.88, p = 0.014), as well as high frequency of eating pasta (AOR = 1.3, p = 0.04) and fast-food consumption (AOR = 1.7, p = 0.042) were independently associated with under-estimated body image. Skipping breakfast (AOR = 1.9, p = 0.017) and having one obese parent (AOR = 1.9, p = 0.01) were independently associated with higher frequency of over-estimated body image. Regarding body image dissatisfaction, independent factors associated with desire to lose weight were: female gender (AOR = 1.53, p = 0.007), high income family financial situation (AOR = 2.1, p = 0.008) and having one parent who is obese (AOR = 2.21, p < 0.001). However, frequent fast-food consumption (AOR = 1.9, p = 0.038) and eating between meals (AOR = 1.57, p = 0.01) were independently associated with a higher desire to gain weight. CONCLUSIONS Our study highlighted that the prevalence of body image distortion and dissatisfaction were substantially high among adolescents. Their determinants included socio-demographic factors and lifestyle behaviors. Increased awareness among parents, educators and public health planners may help adolescents improve accuracy of body image attitudes.
Collapse
|
|
6 |
9 |
21
|
Ketata N, Ben Ayed H, Ben Hmida M, Trigui M, Ben Jemaa M, Yaich S, Maamri H, Baklouti M, Jedidi J, Kassis M, Feki H, Damak J. Point prevalence survey of health-care associated infections and their risk factors in the tertiary-care referral hospitals of Southern Tunisia. Infect Dis Health 2021; 26:284-291. [PMID: 34334351 DOI: 10.1016/j.idh.2021.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 06/19/2021] [Accepted: 06/23/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Health-care associated infections (HAI) are considered a public health problem and have substantial effect on mortality and morbidity. This study aimed to determine the prevalence of HAI in South Tunisian University Hospitals (UH) and to identify their risk factors. METHODS We performed a point prevalence study, in the UH of Southern Tunisia in February 2019, including all hospitalized patients for at least 48 hours. RESULTS Overall, 898 patients were included in this survey, among whom 480 participants (53.5%) were males. There were 81 HAIs, accounting for a prevalence of HAI of 9.02%. Urinary tract infections (28.4%) were the most common HAI, followed by respiratory tract infections (22.2%). The main identified microorganisms among HAI patients were Klebsiella pneumonia (22.7%) and Escherichia coli (20.7%). Independent intrinsic risk factors of high prevalence of HAI were diabetes (Adjusted Odds Ratio (AOR)=3.5;p=0.016) having a rapidly fatal disease (AOR=4;p=0.024) and an ASA scores ≥2 (AOR=2.8;p=0.045). As for extrinsic risk factors, admission in ICU (AOR=11.1;p= 0.04), a length of hospital stay ≥ 7 days (AOR=4.1;p=0.04), previous hospitalization within 90 days prior to the admission (AOR=4.2;p=0.01) and having a peripheral vascular catheter (AOR=6.7; p=0.039) were independently associated with higher prevalence of HAI. Lower prevalence of HAI was independently associated with prescription of antimicrobial preoperative prophylaxis (AOR= 0.1; p=0.02). CONCLUSION Our findings illustrated high prevalence of HAI in South Tunisian Hospitals, affecting principally fragilized patients who may require special needs. Therefore, promoting hygiene programs for health professionals to establish patient safety's culture is urgently needed.
Collapse
|
Journal Article |
4 |
7 |
22
|
Feki M, Belal S, Feki H, Souissi M, Frih-Ayed M, Kaabachi N, Hentati F, Ben Hamida M, Mebazaa A. Serum Vitamin E and Lipid-adjusted Vitamin E Assessment in Friedreich Ataxia Phenotype Patients and Unaffected Family Members. Clin Chem 2002. [DOI: 10.1093/clinchem/48.3.577] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
|
|
23 |
7 |
23
|
Ahmed AB, Feki H, Abid Y, Minot C. Molecular structure, vibrational spectra and nonlinear optical properties of orthoarsenic acid-tris-(hydroxymethyl)-aminomethane DFT study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 75:1315-1320. [PMID: 20117044 DOI: 10.1016/j.saa.2009.12.073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Revised: 12/19/2009] [Accepted: 12/31/2009] [Indexed: 05/28/2023]
Abstract
In this work, we report a theoretical study on molecular structure, vibrational spectra and nonlinear optical properties of orthoarsenic acid-tris-(hydroxymethyl)-aminomethane (OATA). The theoretical geometrical parameters in the ground state have been investigated by density functional method (B3LYP and BLYP) with 6-311G(d,p) basis set. The influence of intermolecular interactions effects on molecular properties has been considered by calculation performed on (OATA) dimer. The optimized geometric bond lengths and bond angles are in well agreement with the experimental data. As compared to theoretical frequencies of the monomer, the calculated values obtained for (OATA) dimer are in much better agreement with the experiment. All experimental vibrational bands have been discussed and assigned to normal modes on the basis of our theoretical calculations. B3LYP method has shown better fit to experimental ones than BLYP in calculation vibrational frequencies. To investigate nonlinear optical behaviour, the electric dipole moment mu, the polarizability alpha and the hyperpolarizability beta were computed using DFT//B3LYP/6-311G(d,p) method.
Collapse
|
|
15 |
5 |
24
|
Ben Ayed H, Yaïch S, Ben Jmaa M, Jedidi J, Ben Hmida M, Trigui M, Kassis M, Karray R, Mejdoub Y, Feki H, Damak J. Pediatric respiratory tract diseases: Chronological trends and perspectives. Pediatr Int 2018; 60:76-82. [PMID: 28891268 DOI: 10.1111/ped.13418] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 08/30/2017] [Accepted: 09/05/2017] [Indexed: 12/30/2022]
Abstract
BACKGROUND The aim of this study was to describe the epidemiological profile of childhood respiratory tract diseases (RTD) in the region of Sfax, Tunisia, and to evaluate their trends over a 13 year period. METHODS We conducted a retrospective study of all children hospitalized with RTD aged under 14 years. We collected data from the regional morbidity register of the university hospital of Sfax from 2003 to 2015. RESULTS A total of 10 797 RTD patients were enrolled from 49 880 pediatric hospitalizations (21.7%). A male predominance was noted (60%). The median age was 8 months (IQR, 2-36 months). Acute bronchitis (AB) accounted for 53.8%, followed by asthma (15%), pneumonia (14%) and acute upper respiratory infection (AURI; 7.2%). The hospital incidence rate (HIR) of RTD was 34/10 000 inhabitants/year. It was 18.2; 5.07; 4.7 and 2.4/10 000 inhabitants for AB, asthma, pneumonia and AURI, respectively. We noted a significant increase in the HIR of RTD with an annual percentage change (APC) of 10.94% (P < 0.001); in the HIR of AB (APC, 5.27%; P < 0.001); and in asthma HIR (APC, 11.2%; P < 0.001). Otherwise, a significant decrease in AURI HIR was observed (APC, -8.8%; P < 0.001). AB lethality rate increased significantly, with an APC of 7.4% (P < 0.001). Projected trends analysis up to 2024 showed a significant rise in AB and in asthma, while AURI would significantly decrease. CONCLUSIONS RTD continues to be a serious health problem over time in terms of morbidity and mortality. Preventive and curative strategies are needed urgently.
Collapse
|
|
7 |
5 |
25
|
Jaballi R, Maalej W, Atoui D, Feki H, Ben Salem R, Elaoud Z. Crystal packing, vibrational studies, DFT calculations of a new hybrid nickel (II)‐complex and its application in Heck and Sonogashira cross‐ coupling reactions. Appl Organomet Chem 2018. [DOI: 10.1002/aoc.4366] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
|
7 |
5 |