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1.
Cureus ; 14(8): e27971, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36134081

RESUMEN

Background The burden of psychiatric illness following a head injury may have implications on the disease prognosis. The present study evaluated the association of depression and anxiety with traumatic brain injury (TBI). Methods A case-control study was conducted in Karachi, Pakistan, from 2nd July 2021 and 30th January 2022, including individuals of age 18 and above of both genders, with or without a mild head trauma history, forming the case and control groups, respectively. Individuals with previous head trauma/congenital neurological dysfunction were excluded. A mental health assessment of the participants was carried out with two scales, the Generalized Anxiety Disorder-7 (GAD-7) scale and the Public Health Questionnaire-9 (PHQ-9) scale. Other parameters like age, gender, socioeconomic status, education status, and comorbidities were also documented. Results A total of 62 participants were enrolled with 31 cases and 31 controls. The majority were males aged between 18 and 39 years. About 29% of the patients with a history of mild TBI had moderate to severe depression while only 22.6% of them did not have depression or had minimal depression. We found that about 29.3% of patients with TBI had severe anxiety as compared to the only two healthy controls. The majority of the control group participants did not have anxiety. Conclusion Traumatic head injuries and their long-term side effects can predispose patients to a myriad of psychiatric comorbidities. In this study, we found definitive evidence that both anxiety and depression had a significantly higher incidence in cohorts that suffered from mild TBI. However, we recommend large-scale and multicenter studies in the future to explore these relationships more thoroughly and comprehensively.

2.
Soc Neurosci ; 15(5): 571-583, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32715953

RESUMEN

Although romantic rejection and acceptance have a strong impact on mood in adults, their neural response patterns are relatively unexplored. The present study used functional magnetic resonance imaging (fMRI) to examine neural responses to romantic rejection and acceptance in 36 healthy men and women, ages 18-53 years. Activations during rejection showed extensive anatomical overlap with activations during acceptance in the ventrolateral prefrontal cortex (vlPFC) and anterior insula (AI). In an analysis of sex differences, men and women did not differ in behavioral responses; however, men showed greater activation to romantic rejection and acceptance in the left vlPFC and AI compared to women. The vlPFC and AI may play a role in social cognition, tuned to detect the intentions and feelings of others whether they are positive or negative. In the context of romantic rejection and acceptance, this activation may signal the intent of others who are desired by the individual, leading to changes in mood, self-esteem, and social motivation.


Asunto(s)
Fenómenos Fisiológicos del Sistema Nervioso , Rechazo en Psicología , Adolescente , Adulto , Afecto , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiología , Cognición , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Motivación , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Autoimagen , Caracteres Sexuales , Percepción Social , Adulto Joven
3.
Dalton Trans ; 47(2): 376-381, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-29218346

RESUMEN

Monodisperse cobalt chromium ferrite (FeCoCrO4) nanoparticles have been synthesised using the trimetallic pivalate cluster [CrCoFeO(O2CtBu)6(HO2CtBu)3]. The precursor was thermolysed in oleylamine and oleic acid, with diphenyl ether as the solvent at 260 °C. The effect of time and the concentration of the precursor on the stoichiometry of the phase formed and/or the morphology of the nanoparticles was studied. The reaction time was investigated by withdrawing aliquots at different times. No products were formed after 5 minutes and aliquots withdrawn at reaction times of less than 1 hour contain traces of iron oxide (Fe2O3); only cubic cobalt chromium ferrite (FeCoCrO4) was obtained after one hour. Transmission Electron Microscopy (TEM) showed that more monodisperse spherical ferrite nanoparticles (4.0 ± 0.4 nm) were obtained at higher precursor concentrations. Magnetic measurements revealed that all the ferrite particles are superparamagnetic at room temperature but showed large hysteresis at low temperature. The nanoparticles were characterised by Powder X-Ray Diffraction (p-XRD) and Transmission Electron Microscopy (TEM). A Superconducting Quantum Interference Device (SQUID) was used to analyse the magnetic properties of the nanoparticles.

4.
Chemistry ; 22(37): 13127-35, 2016 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-27505614

RESUMEN

New complexes catena-(µ2 -nitrato-O,O')bis(piperidinedithiocarbamato)bismuth(III) (1) and tetrakis(µ-nitrato)tetrakis[bis(tetrahydroquinolinedithiocarbamato)bismuth(III)] (2) were synthesised and characterised by elemental analysis, FTIR spectroscopy and thermogravimetric analysis. The single-crystal X-ray structures of 1 and 2 were determined. The coordination numbers of the Bi(III) ion are 8 for 1 and ≥6 for 2 when the experimental electron density for the nominal 6s(2) lone pair of electrons is included. Both complexes were used as single-source precursors for the synthesis of dodecylamine-, hexadecylamine-, oleylamine and tri-n-octylphosphine oxide-capped Bi2 S3 nanoparticles at different temperatures. UV/Vis spectra showed a blueshift in the absorbance band edge characteristic of a quantum size effect. High-quality, crystalline, long and short Bi2 S3 nanorods were obtained depending on the thermolysis temperature, which was varied from 190 to 270 °C. A general trend of increasing particle breadth with increasing reaction temperature and increasing length of the carbon chain of the amine (capping agent) was observed. Powder XRD patterns revealed the orthorhombic crystal structure of Bi2 S3 .

5.
Curr Gene Ther ; 16(2): 83-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27029944

RESUMEN

Gene electrotransfer is an effective approach for delivering plasmid DNA to a variety of tissues. Delivery of molecules with electric pulses requires control of the electrical parameters to achieve effective delivery. Since discomfort or tissue damage may occur with high applied voltage, the reduction of the applied voltage while achieving the desired expression may be an important improvement. One possible approach is to combine electrotransfer with exogenously applied heat. Previous work performed in vitro demonstrated that increasing temperature before pulsing can enhance gene expression and made it possible to reduce electric fields while maintaining expression levels. In the study reported here, this combination was evaluated in vivo using a novel electrode device designed with an inserted laser for application of heat. The results obtained in this study demonstrated that increased temperature during electrotransfer increased expression or maintained expression with a reduction in applied voltage. With further optimization this approach may provide the basis for both a novel method and a novel instrument that may greatly enhance translation of gene electrotransfer.


Asunto(s)
Técnicas de Transferencia de Gen , Animales , Electrodos , Femenino , Expresión Génica , Cobayas , Temperatura
6.
Chem Commun (Camb) ; 50(92): 14328-30, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25284472

RESUMEN

Tin selenide (SnSe) and copper tin selenide (Cu2SnSe3) thin films have been deposited onto glass substrates by AACVD using [Sn(Ph2PSe2)2] or a mixture of [Sn(Ph2PSe2)2] and [Cu(acac)2] respectively.

7.
Clin Nutr ; 32(2): 193-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22981241

RESUMEN

BACKGROUND & AIM: Acute lower respiratory infections are the most frequent illnesses globally in children less than 5 years old. The aim of this randomized double blind controlled trial is to assess the effectiveness of zinc gluconate supplementation for 2 months period compared to placebo in reducing respiratory morbidity in acute lower respiratory infected children up to 5 years of age living in zinc poor population. METHODS: Children were randomly assigned to receive either 10 mg zinc gluconate or placebo for 60 days. Demographic and clinical data were collected at baseline and every two weeks for 180 days. RESULTS: The final analysis included 96 children allocated equally to the two groups. The number of episodes of acute lower respiratory infections and severe acute lower respiratory infections were significantly lower in zinc group compared to placebo group (20.8% vs. 45.8% (P = 0.009) and 21.7% vs. 58.3% (P < 0.001), respectively). The acute lower respiratory infections free days were higher in the zinc supplemented group (P < 0.001). The median recovery time of morbidity was significantly shorter in zinc group (P < 0.001). CONCLUSIONS: Zinc supplement may result in significant reduction in respiratory morbidity among children with acute lower respiratory infections in zinc poor population. This study was registered under ClinicalTrials.gov Identifier no. NCT00536133.


Asunto(s)
Suplementos Dietéticos , Gluconatos/administración & dosificación , Infecciones del Sistema Respiratorio/prevención & control , Zinc/administración & dosificación , Enfermedad Aguda , Preescolar , Método Doble Ciego , Femenino , Humanos , Masculino , Morbilidad , Zinc/deficiencia
8.
Dalton Trans ; 42(1): 196-206, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23132230

RESUMEN

The iron pivalate clusters [Fe(3)O(O(2)C(t)Bu)(6)(H(2)O)(3)](O(2)C(t)Bu)·HO(2)C(t)Bu (1), [Fe(8)(OH)(4)(O(2)C(t)Bu)(12)(OC(6)H(4)C(6)H(5))(8)] (2) and [Fe(3)O(O(2)C(t)Bu)(6)(C(5)H(5)N)(3)] (3) have been used as single source precursors to synthesise iron oxide nanoparticles by a hot injection thermal decomposition method in oleylamine, hexadecanol, oleic acid, oleylamine/oleic acid with dodecanol or octyl ether as solvent. The effect of the different reaction parameters such as temperature, reaction time and capping agents on the phase and morphology were studied. The reaction time was studied for (1) by thermolysis in a mixture of oleylamine, oleic acid, hexadecanol and dodecanol (solvent) at 260 °C. The results obtained showed that a mixture of maghemite-C (Fe(2)O(3)) and magnetite (Fe(3)O(4)) were obtained for aliquots withdrawn for reaction times of less than 30 minutes whilst only magnetite was obtained after one hour. The nanoparticles were characterised by p-XRD, TEM and magnetic measurements. TEM showed that monodispersed magnetite particles were obtained when the precursor was injected at the boiling point of the solvent. The diameter of the monodispersed nanoparticles obtained by the thermolysis of [Fe(3)O(O(2)C(t)Bu)(6)(H(2)O)(3)](O(2)C(t)Bu)·HO(2)C(t)Bu (1) in oleylamine, hexadecanol, oleic acid with dodecanol or octyl ether as solvent were 4.3 ± 0.4 and 4.9 ± 0.5 nm respectively. Magnetic measurements revealed that all the particles are superparamagnetic.

9.
Chem Commun (Camb) ; 48(46): 5703-14, 2012 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-22531115

RESUMEN

Power generation through photovoltaics (PV) has been growing at an average rate of 40% per year over the last decade; but has largely been fuelled by conventional Si-based technologies. Such cells involve expensive processing and many alternatives use either toxic, less-abundant and or expensive elements. Kesterite Cu(2)ZnSnS(4) (CZTS) has been identified as a solar energy material composed of both less toxic and more available elements. Power conversion efficiencies of 8.4% (vacuum processing) and 10.1% (non-vacuum processing) from cells constructed using CZTS have been achieved to date. In this article, we review various deposition methods for CZTS thin films and the synthesis of CZTS nanoparticles. Studies of direct relevance to solar cell applications are emphasised and characteristic properties are collated.

10.
Inorg Chem ; 49(18): 8495-503, 2010 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-20735018

RESUMEN

The iron(III) complexes of several 1,1,5,5-tetraalkyl-2-thiobiurets [Fe(SON(CN(i)Pr(2))(2))(3) (1), Fe(2)(µ-OMe)(2)(SON(CNEt(2))(2))(2) (2), Fe(SON(CNEt(2))(2))(3) (3), and Fe(SON(CNMe(2))(2))(3) (4)] have been synthesized, and the single-crystal X-ray structures of 1, 2, and 4 have been determined. The magnetic properties of complex 2 as a function of the temperature and field were studied. Thermogravimetric analysis of complexes 1-4 showed the decomposition in one major step to iron sulfide residues. All four complexes were used as single-source precursors for the deposition of iron sulfide thin films by aerosol-assisted chemical vapor deposition. Complex 1 gave hexagonal troilite FeS films with a small amount of tetragonal pyrrhotites Fe(1-x)S at 300 °C, whereas only troilite FeS was deposited at 350, 400, or 450 °C. Complexes 2 and 3 deposited a mixture of hexagonal troilite FeS and cubic pyrite FeS(2) films at all temperatures. Complex 4 deposited very thin films of FeS at all temperatures as troilite. Scanning electron microscopy images of the films deposited from all complexes showed that the morphology consisted of plates, granules, rods, and sheets like crystallites. The size and shapes of these crystallites were dependent on the growth temperature and the precursor used. This is the first time that iron(III) thiobiuret complexes have been used as single-source precursors for iron sulfide thin films.

11.
Philos Trans A Math Phys Eng Sci ; 368(1927): 4249-60, 2010 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-20732885

RESUMEN

Cobalt complexes of 1,1,5,5-tetramethyl-2,4-dithiobiuret, [Co{N(SCNMe(2))(2)}(3)] (1), and 1,1,5,5-tetraisopropyl-2-thiobiuret, [Co{N(SOCN(i)Pr(2))(2)}(2)] (2), have been synthesized and characterized. Both complexes were used as single-molecule precursors for the preparation of cobalt sulphide nanoparticles by thermolysis in hexadecylamine, octadecylamine or oleylamine. The powder X-ray diffraction pattern of as-prepared nanoparticles showed the hexagonal phase of Co(1-x)S from complex 1 and mixtures of cubic and hexagonal Co(4)S(3) from complex 2. Transmission electron microscopy images of material prepared from complex 1 showed spherical and trigonally shaped particles in the size range of 10-15 nm; whereas spheres, rods, trigonal prisms and pentagonally and hexagonally faceted crystallites were observed from complex 2. This observation is the first of the Co(4)S(3) phase in a nanodispersed form.

12.
Dalton Trans ; 39(26): 6080-91, 2010 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-20514380

RESUMEN

The series of nickel dichalcogenoimidodiphosphinates [Ni{(i)Pr(2)P(X1)NP(X2)(i)Pr(2)}(2)]: X1 = S, X2 = Se (1), X1 = X2 = S (2), and X1 = X2 = Se (3) have been successfully used as single-source precursors (SSPs) to deposit thin films of nickel sulfide, selenide or phosphide; the material deposited depended on both temperature and method used for the deposition. Aerosol-assisted (AA) chemical vapour deposition (CVD) and low-pressure (LP) CVD were used. The as-deposited films were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). A variety of phases including: Ni(2)P, Ni(0.85)Se and NiS(1.03) were deposited under different conditions. The mechanism of decomposition to the phosphide, selenide, or sulfide was studied by pyrolysis gas chromatography mass spectrometry (Py-GC-MS) and modelled by density functional theory (DFT).

13.
J Am Chem Soc ; 132(6): 1780-1, 2010 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-20095601

RESUMEN

Nanoparticles of Au, Ag, CdS, and CdSe have been linked together by a chemical reaction to form controlled assemblies of similar or different types of nanoparticles through amido or azo linkage. The capping of nanoparticles was exchanged with bifunctional groups containing active functional groups at the tails. The reaction between the tails of the capping agents resulted in the formation of amido or azo linkages. These reactions were carried out under very dilute conditions to control the assembly and avoid the polymerization. The assemblies formed included the dimers, trimers, tetramers, and hexa- or heptamers. These reactions are the first examples for the systematic approach to establish the chemical route for the controlled assembly of nanoparticles and open the way for the fabrication of nanoparticle based devices for various application.

14.
Dalton Trans ; 39(6): 1460-3, 2010 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-20104303

RESUMEN

A series of new metal complexes of thiobiurets and dithiobiurets have been synthesized and characterized. The compounds are potentially useful as novel single source precursors for the deposition of metal sulfide thin films or nanoparticles.

15.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): o2781, 2010 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-21588979

RESUMEN

The title compound, C(15)H(14)N(2)O·0.67H(2)O, was prepared by the reaction of 4-acetoamine-benzaldehyde and aniline. The asymmetric unit contains six organic mol-ecules and four water mol-ecules. The dihedral angles between the aromatic ring planes in each organic mol-ecule vary from 42.4 (2) to 53.8 (2)°. In the crystal, an extensive network of inter-molecular N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds link the mol-ecules into [010] chains.

16.
Dalton Trans ; (28): 5487-94, 2009 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-19587992

RESUMEN

Two heterobimetallic precursors [Zn(TFA)3(micro-OH)Cu3(dmae)3Cl].THF (1) and [Zn(TFA)4Cu3(dmae)4] (2) [dmae=N,N-dimethylaminoethanolate and TFA=trifluoroacetate], have been synthesized and characterized by their melting points, elemental analysis, FT-IR spectroscopy, mass spectrometry, TGA and single crystal X-ray diffraction methods. Both complexes were used to deposit thin films of Cu-ZnO composite on glass substrates by aerosol assisted chemical vapor deposition (AACVD) method. The films were characterized by "scotch tape" test for adhesion, thickness measurement as a function of temperature, EDX for composition, SEM for surface morphology and XRD for crystalline phases. Thin film deposition studies at 250, 325, 400, 475 degrees C indicated the increase in thickness with temperature reaching a maximum at 400 degrees C and then decreasing. EDX and PXRD results showed the uniform distribution of cubic metallic copper and hexagonal zinc oxide phases which make them useful for nanocatalysis on structured surfaces.

17.
Dalton Trans ; (12): 2103-8, 2009 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-19274288

RESUMEN

Nickel phosphide (Ni(2)P and Ni(12)P(5)) or nickel selenide (NiSe) nanoparticles were prepared from the single molecule precursor, dialkyldiselenophosphinato nickel(II), [Ni(Se(2)PR(2))(2)] (R = (i)Pr, (t)Bu and Ph) by thermolysis in trioctylphosphine oxide (TOPO) or hexadecylamine (HDA). The chemical composition of these nanoparticles depends on the precursors, capping agents, and reaction temperature.

18.
Dalton Trans ; (12): 2196-200, 2009 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-19274298

RESUMEN

A facile method for the preparation of dimorpholides of dithioacetylacetonate is described together with a X-ray single crystal structure of the ligand and of [Cd(msacmsac)(2)(NO(3))(2)] (msacmsac = dimorpholinodithioacetylacetonate). The cadmium complex has been used as a single source precursor for the deposition of the CdS thin films by the aerosol assisted chemical vapour deposition (AACVD) method or as nanorods by thermolysis in oleylamine. The thin films and nanorods were characterized by electronic spectra (UV-Vis), photoluminescence (PL), X-ray diffraction (XRD), selected area electron diffraction (SAED), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). To the best of our knowledge [Cd(msacmsac)(2)(NO(3))(2)] is the first complex in its class to be used as a single source precursor to deposit CdS thin films or nanoparticles.

19.
Analyst ; 133(10): 1449-52, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18810294

RESUMEN

There is a need for a method to facilitate the development of novel, reproducible colloidal surface-enhanced Raman scattering (SERS) substrates to encourage the use of SERS in applied studies. In this study we show for the first time that by using suitably designed SERS experiments in conjunction with multivariate analysis of variance (MANOVA), an objective assessment of colloidal SERS reproducibility can be made. This is demonstrated with the analyte cresyl violet, but could be extended to any analyte of interest for which reproducible SERS data are needed.


Asunto(s)
Interpretación Estadística de Datos , Oro , Nanopartículas del Metal , Espectrometría Raman/métodos , Absorción , Benzoxazinas , Coloides , Ácido Edético , Oxazinas , Plata , Propiedades de Superficie
20.
Dalton Trans ; (33): 4499-506, 2008 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-18698454

RESUMEN

The complexes [Ni{(SeP(i)Pr(2))(2)N}(2)] (2), [Ni(Se(2)P(i)Pr(2))(2)] (), and [Co(Se(2)P(i)Pr(2))(2)] (4) were synthesised and the X-ray single crystal structures of (1) and (2) were determined. Thin films of nickel selenide, cobalt selenide and cobalt phosphide have been deposited by the chemical vapour deposition method using imidodiselenophosphinato-nickel(ii) (1), -cobalt(ii) [Co{(SeP(i)Pr(2))(2)N}(2)] (3), diselenophosphinato-nickel(ii) (2), -cobalt(ii) (4) and diselenocarbamato-nickel(ii) [Ni(Se(2)CNEt(2))(2)] (5), and -cobalt(iii) [Co(Se(2)CNEt(2))(3)] (6) precursors.

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