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1.
Indian J Community Med ; 40(3): 182-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26170543

RESUMO

BACKGROUND: Obesity in adolescence is crucial as it represents an important stage in human life. Dietary habits are greatly associated with lifestyle. Many reports suggested direct relationship between adolescent fatness and increased risk of cardiovascular diseases (CVD) which will be found in young adult population. AIM: Determine the prevalence of overweight and obesity among male adolescents in Arar city, Saudi Arabia (KSA). We estimated the future risk of developing cardiovascular diseases in this age-group and its possible correlation to different lifestyles and dietary habits. RESULTS: A total of 523 male students with a mean age of 16.7 ± 0.9 years participated in the current study in which 30.4% of those students were obese and 17.2% were overweight. A direct relationship was found between body weight and different dietary and lifestyle habits. The risk of CVD based on waist height ratio (WHtR) was found in 33.5% of participants (30.4% obese, 2.1% overweight and 1% normal weight); moreover, the risk of CVD was strongly related to different dietary and lifestyle habits. CONCLUSION: Overweight and obesity were high among adolescent male students in Arar, who became susceptible to the risk of CVD. Arar showed the highest rate of obesity all over KSA. Both obesity and risk of CVD were strongly related to bad dietary habits and lifestyle.

2.
Anal Sci ; 22(6): 877-81, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16772689

RESUMO

Two novel potentiometric sensors that are highly selective to Hg2+ ions are described. These are based on the use of 5,5'-dithio-bis(2-nitrobenzoic acid) (DTNB) and tricyclazole (TCZ) as neutral carriers in plasticized poly(vinyl chloride) membranes. Fast Nernstian responses are obtained for Hg2+ ions over the concentration ranges 7.0 x 10(-6) - 1.0 x 10(-2) and 7.7 x 10(-6) - 1.0 x 10(-2) mol l(-1) at pH 1.8 - 3.3 with lower detection limits of 5.0 x 10(-6) and 5.6 x 10(-6) mol l(-1) (approximately 1 microh ml(-1)) and calibration slopes of 30.0 and 29.7 mV decade(-1) with DTNB- and TCZ-based membrane sensors, respectively. Validation of the assay method reveals good performance characteristics, including long life span, good selectivity for Hg2+ ions over a wide variety of other metal ions, long term response stability, and high reproducibility. Applications for direct determination of mercury in hazardous wastes including dental amalgam, mercury bulbs, and fluorescent lamps give results with good correlation with data obtained using cold vapor atomic absorption spectrometry.


Assuntos
Técnicas de Química Analítica/métodos , Íons , Mercúrio/análise , Polímeros/química , Espectrofotometria Atômica/métodos , Calibragem , Ligas Dentárias , Ácido Ditionitrobenzoico/análise , Resíduos Perigosos , Concentração de Íons de Hidrogênio , Ionóforos/análise , Modelos Químicos , Cloreto de Polivinila/química , Potenciometria , Espectrofotometria Atômica/instrumentação , Tiazóis/análise
3.
Anal Chim Acta ; 570(2): 232-9, 2006 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-17723404

RESUMO

A novel spectrophotometric assay method for batch and flow injection determination of sulfite in beverages is described. The method involves a reaction with diaquacobyrinic acid heptamethyl ester (diaquacobester, DACbs) in acetate buffer of pH 3 to form a highly stable sulfite cobester complex (SO3Cbs). In the absence of sulfite, the reagent displays three absorption maxima at 349, 409 and 525 nm. Addition of sulfite is associated with the development of a new absorption band at 313 nm, an increase in the intensity of the band at 425 nm and a decrease in the absorbance of the bands at 349 and 525 nm. Variations of the absorptions at 313, 349, 425 and 525 nm are linearly proportional to sulfite concentrations over the range of 0.05-25 microg ml(-1)with a detection limit of 0.01-0.2 microg ml(-1). Negligible interferences are caused by most common ions. Validation of the method according to the quality assurance standards shows suitability for quality control assessment of sulfite in complex matrices without prior treatment. The method has the advantages of high selectivity, good sensitivity, fast reaction, high stability of the reagent and reaction product and absorbance measurements at four different wavelengths in the same run. The method is successfully applied to determine the sulfite contents of some beverages. The results compare fairly well with data obtained using the standard method.

4.
Talanta ; 66(4): 1034-41, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970088

RESUMO

Two novel membrane sensors sensitive and reasonably selective for Cu(2+) ions are described. These are based on the use of newly synthesized cyclic tetrapeptide derivatives as neutral ionophores and sodium tetraphenylborate (NaTPB) as an anionic excluder in plasticized PVC membranes. The sensors exhibit fast and stable near-Nernstian response over the concentration range 1.0x10(-6)moll(-1) to 1.0x10(-2)moll(-1) Cu(2+) with a cationic slope of 30.2-25.9mV per decade at pH 4.5-7 with a lower detection limit of 0.05-0.13mugml(-1). Effects of plasticizers, lipophilic salts and various foreign common ions are tested. The sensors display long life-span, long term stability, high reproducibility, and short response time. Selectivity of both sensors is significantly high for Cu(2+) over Fe(3+), Al(3+), Zn(2+), Cd(2+), Hg(2+), Ni(2+), Co(2+), Mn(2+), alkaline earth and alkali metal ions. The sensors are used for direct measurement of copper content in different rocks and industrial wastewater samples from electroplating factories. The results agree fairly well with data obtained using atomic absorption spectrometry.

5.
Talanta ; 60(1): 81-91, 2003 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-18969028

RESUMO

New membrane sensors with cylindrical configuration for lead (II) ions are described based on the use of three newly synthesized pyridine carboximide derivatives as neutral ionophores in plasticized PVC membranes. The sensors exhibit significantly enhanced response towards lead (II) ions over the concentration range 4x10(-6)-1x10(-2) mol l(-1) at pH 4.5-7 with a lower detection limit of 0.4-3.7 mug ml(-1). The sensors display near-Nernstian slope of 26.0-33.1 mV per decade for Pb(II) ions. Effects of plasticizers, lipophilic salts and various foreign common ions are tested. The sensors show long life span, good selectivity for Pb(II) over a wide variety of other metal ions, long term stability, high reproducibility, and fast response. Validation of the method by measuring the lower detection limit, range, accuracy, precision, repeatability and between-day-variability reveals good performance characteristics of the proposed sensors. The sensors are used for direct determination of lead in stack emissions of lead smelters, assay of lead in rocks and monitoring of potentiometric titration of Pb(II) with EDTA. The results obtained agree fairly well with data obtained by atomic absorption spectrometry.

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