RESUMEN

Blend nanocomposite film was prepared by loadings of irradiated ZnO in ratios of (5 wt%) inside the PVC/HDPE matrix using a hot-melt extruder technique. The physical and chemical properties of the irradiated and unirradiated ZnO samples are compared. The Vis-UV spectrum of ZnO shows an absorption peak at a wavelength of 373 nm that was slightly red-shifted to 375 nm for an irradiated sample of ZnO at a dose of 25 kGy due to the defect of crystal structure by the oxygen vacancy during gamma irradiations. This growth of the defect site leads to a decrease in energy gaps from 3.8 to 2.08 eV. AC conductivity of ZnO sample increased after the gamma irradiation process (25 kGy). The (PVC/HDPE)/ZnO nanocomposites were re-irradiated with γ rays at 25 kGy in the presence of four different media (silicon oil, sodium silicate, paraffin wax and water). FTIR and XRD were performed to monitor the changes in chemical composition. The new peak at 1723 cm-1 attributed to C=O groups was observed in irradiated (PVC/HDPE)ZnO samples at only sodium silicate and water media. This process induced new function groups on the surface of the (PVC/HDPE)/ZnO blend sample. This work aims to develop (PVC/HDPE)ZnO for oil/water separation. The highest oil adsorption capability was observed in samples functionalized by C=O groups based on the different tested oils. The results suggest that the surface characterization of the (PVC/HDPE)/ZnO can be modified to enhance the oil adsorption potential. Further, the gamma irradiation dose significantly enhanced the AC conductivity compared to the unirradiated sample. According to COMSOL Multiphysics, the irradiated sample (PVC/HDPE)ZnO in water shows perfect uniform electric field distribution in medium voltage cables (22.000 V).

RESUMEN

In some cases, blends containing PVC and LLDPE show low compatibility. Adding styrene-butadiene rubber to the PVC/LLDPE mixtures leads to a noticeable increase in tensile strength and compatibility of the blends. Also, an improvement in tensile strength is observed after incorporating SBR compatibilizer resulting in entirely different gamma irradiation doses. Without a compatibilizer, the mixture exhibits a distributed PVC and LLDPE phase with variable sizes and shapes; even a sizable portion of the domains resemble droplets. Styrene butadiene rubber (SBR) and gamma radiation make mixtures of (PVC/LLDPE) more compatible. The SEM study of the blends demonstrated that adding the compatibilizer resulted in finer blend morphologies with less roughness. At the same time, gamma irradiation reduced this droplet and gave a more smooth surface. Poly(vinyl chloride) (PVC) was chemically modified with four different amino compounds, including ethylene diamine (EDA), aniline (An), p-anisidine (pA) and dimethyl aniline (DMA) for improving the electric conductivity and oil removal capability of the blend polymer. All ionomers were prepared by nucleophilic substitution in a solvent/non-solvent system under mild conditions. This work novelty shows a sustainable route for producing oil adsorption materials by recycling plastic waste. After the amination process of poly(vinyl chloride) the oil adsorption was significantly enhanced.

Asunto(s)

Cloruro de Vinilo , Óxido de Zinc , Butadienos , Cloruro de Polivinilo/química , Estirenos , Conductividad Eléctrica , Compuestos de Anilina

RESUMEN

Increasing body mass index (BMI) has reached epidemic proportions globally and recently emerged as strong, independent risk factors for chronic kidney disease (CKD). We conducted this study to verify the prevalence of obesity and the associated risk of developing CKD among 3000 Egyptian students. The World Health Organization classification of BMI categorized study population into 1-5 groups, 1146 subjects with normal BMI (20-25), 951 subjects with BMI 25-29.9, 540 subjects with BMI 30-34.9, 225 with BMI 35-39.9, and 138 with BMI above 40. The participants were subjected to clinical examination, anthropometric measurements, laboratory investigation, including urinary albumin/creatinine ratio (ACR) and estimation of glomerular filtration rate (eGFR). The prevalence of overweight, obesity, and metabolic syndrome (MS) was 31.7%, 30.1%, and 16%, respectively. The prevalence of CKD among subjects with BMI >25 was 6.5%, almost all of them had BMI >35. ACR and eGFR rose progressively with increasing BMI. Elevated mean arterial pressure (MAP), high sensitivity C-reactive protein, and MS increased the risk of development of CKD. Moreover, MAP, waist to height ratio, and triglycerides to high-density lipoprotein ratios at levels of >95 mm Hg, >0.6, and >3 had sensitivity 91.7%, 88.4%, and 86.7%; and specificity 92.3%, 96.4%, and 96.5%, respectively to predict CKD. The prevalence of obesity among Egyptian young adults was high (30.1%) and was associated with increased the risk of CKD (6.5%).

RESUMEN

OBJECTIVE: This study investigated improvements in quality of life associated with eight weeks of montelukast and/or intranasal steroid treatment for moderate to severe allergic rhinitis. METHODS: A single-centre, prospective, randomised, double-blind, placebo-controlled study was carried out. Assessments were made using the Rhinoconjunctivitis Quality of Life Questionnaire and symptom scales. RESULTS: A total of 128 patients (aged 13-51 years) were randomly assigned to one of two groups. In the montelukast group, patients were treated with montelukast tablets and fluticasone propionate nasal spray (n = 64). In the placebo group, treatment comprised a placebo and fluticasone propionate. The results showed significant improvements in symptom scores and quality of life scores for both groups after one month and two months of treatment, compared with baseline values; these improvements were significantly greater for the montelukast group compared with the placebo group. The mean number of loratadine tablets taken by each patient during the study period was only 0.73 for the montelukast group compared with 9 for the placebo group. CONCLUSION: The combination of montelukast tablets and fluticasone propionate nasal spray improved symptom control and overall quality of life for moderate to severe allergic rhinitis patients.

Asunto(s)

Acetatos/uso terapéutico , Androstadienos/uso terapéutico , Antialérgicos/uso terapéutico , Glucocorticoides/uso terapéutico , Antagonistas de los Receptores Histamínicos H1 no Sedantes/uso terapéutico , Antagonistas de Leucotrieno/uso terapéutico , Calidad de Vida , Quinolinas/uso terapéutico , Rinitis Alérgica Estacional/tratamiento farmacológico , Administración Intranasal , Adolescente , Adulto , Androstadienos/administración & dosificación , Ciclopropanos , Método Doble Ciego , Quimioterapia Combinada , Femenino , Fluticasona , Estudios de Seguimiento , Glucocorticoides/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Rinitis Alérgica Estacional/diagnóstico , Índice de Severidad de la Enfermedad , Sulfuros , Encuestas y Cuestionarios , Resultado del Tratamiento

RESUMEN

Liquid nitrogen preservation in remote farms is a limitation. The goal of this study was to determine optimum temperature above freezing point for bovine spermatozoa preservation using bovine serum albumin (BSA) as a supplementation. Pooled semen sample from three ejaculates was subjected to various BSA concentration (1, 4, 8 and 12 mg ml(-1)), before incubation in different above freezing point temperatures (4, 25 and 37 °C). Viability assessment was carried out against time from day 0 (fresh sample) until all spermatozoa become nonviable. Optimal condition for bovine spermatozoa storage was at 4 °C with 1 mg ml(-1) BSA for almost 7 days. BSA improved bovine spermatozoa viability declining rate to 44.28% at day 4 and 57.59% at day 7 compared to control, with 80.54% and 98.57% at day 4 and 7 respectively. Increase in BSA concentration did not improve sperm viability. Our results also confirmed that there was a strong negative correlation between media osmolarity and bovine spermatozoa survival rate with r = 0.885, P < 0.0001. Bovine serum albumin helps to improve survival rate of bovine spermatozoa stored above freezing point.

Asunto(s)

Criopreservación , Congelación , Preservación de Semen , Albúmina Sérica Bovina/fisiología , Espermatozoides , Animales , Bovinos , Masculino , Concentración Osmolar

RESUMEN

Differential pulse polarography was used to study the mixed ligand complexes of imidazole and some dicarboxylate anions namely, oxalate, tartrate and malonate with Cd(II) at constant ionic strength (mu = 1, NaNO(3)) at 25 +/- 0.1 degrees . It has been found that the reduction of complexes is reversible and diffusion-controlled. Three mixed complexes are formed with malonate (or oxalate) whereas four mixed complexes are formed with tartrate. The overall stability constants for each system were calculated and discussed.

RESUMEN

A detailed study of the complexes formed between 1-hydroxyethane-1,1-diphosphonic acid and twelve metal ions, including the alkaline earth and transition non-transition metal ions, is reported. The formation constants of the protonated and unprotonated complexes are measured from potentiometric data and possible structural formulae are given. The results reveal that only mononuclear (1:1) di-, mono- and unprotonated metal chelates are formed and that the general order of stability for the unprotonated complexes is Zn > Mn > Ca > Cu > Cd > Pd > Ni > Co reverse similar Sr > Mg > Ag > Ba.