Rendimiento estático y cíclico de compuestos cementantes reforzados con fibras de vidrio

This paper concerns an experimental study of the influence of short glass-fibres randomly oriented of a reinforced cement-based composite on the mechanical behaviour. The matrix material parameters used are: cement/sand ratio and water/cement ratio fixed at 0.5; the glass-fibre content (0%, 0.5%, 1.0%, 1.5%, 2% and 2.5%) and fibre lengths (3, 6 and 12 mm). Composites mechanical characterisation under static behaviour at flexural and compression tests, shows that the reinforcement effect is beneficial only in flexural case. A synergy (matrix-reinforcement) was observed when fibre length of 12 mm is used with application rate of 2% in flexural. The fatigue behaviour determined by Wöhler plots (stress-number of cycles to rupture), derived from experimental results; showed a large results dispersion which is attributed to many causes initiating this damage. The cyclic tests illustrate brittle character of these materials; even with low-amplitude cycles of loading no adaptation of these materials can be reported.Este trabajo aborda el estudio experimental de la influencia de fibras de vidrio cortas orientadas al azar sobre el comportamiento mecánico de un composite reforzado de base cemento. Los parámetros de la matriz utilizados son: relación cemento/arena y relación agua/cemento fijada en 0,5; el contenido de fibra de vidrio (0%, 0,5%, 1,0%, 1,5%, 2% y 2,5%) y longitudes de fibra (3, 6 y 12 mm). Los resultados mecánicos de estos compuestos bajo comportamiento estático (flexión y compresión), muestran que el efecto de refuerzo es beneficioso unicamente a flexión. Se observó una sinergia (refuerzo de la matriz) cuando se usó la fibra de 12 mm con una tasa de aplicación del 2% en flexión. El comportamiento a fatiga determinado por las curvas de Wöhler (número de ciclos hasta la rotura), derivado de los resultados experimentales; mostró una gran dispersión de resultados que se atribuye a las muchas causas que pueden iniciar este daño. Las pruebas cíclicas ilustran el carácter quebradizo de estos materiales; y no se pude indicar que exista adaptación de estos materiales, incluso con ciclos de carga de baja amplitud

A facile and green synthetic approach toward fabrication of alcea- and thyme-stabilized tio2 nanoparticles for photocatalytic applications

A facile and green synthetic approach was considered for the synthesis of stabilized titanium dioxide (TiO2) nanoparticles. Extracts of Alcea and Thyme plants were used to synthesis TiO2 nanoparticles for photocatalytic applications. Evaluation of the structural and phase formation via X-ray diffraction (XRD) indicated the formation of the anatase phase of TiO2 along with the rutile phase. A desired single phase of anatase was obtained upon heating the as-synthesized samples at 500 °C for 3 h. Using the information provided by the XRD analyzer and the Debye Scherer relationship, the average crystallite size was found to be around 6 and 10 nm for the samples synthesized using Alcea and Thyme plants, respectively. To determine the elemental analysis and chemical structure, the energy dispersive X-ray (EDX) analyzer and Fourier Transform Infrared (FTIR) spectroscopy were employed. Field emission scanning electron microscopy (FESEM) indicated batches of ultrafine agglomerated particles for both samples, which their sizes grew by the heating process. The UV–visible analysis of photocatalytic properties confirmed the priority of TiO2 nanoparticles prepared with Thyme extracts

Mode-locking induced by coherent driving in fiber lasers

Mode-locking is a broad concept that encompasses different processes enabling short optical pulse formation in lasers. It typically requires an intracavity mechanism that discriminates between single and collective mode lasing, which can be complex and sometimes adds noise. Moreover, known mode-locking schemes do not guarantee phase stability of the carrier wave. Here, we theoretically propose that injecting a detuned signal seamlessly leads to mode-locking in fiber lasers. We show that phase-locked pulses, akin to cavity solitons, exist in a wide range of parameters. In that regime the laser behaves as a passive resonator due to the non-instantaneous gain saturation

ANTIOXIDANT EFFECT OF VITAMINS COMBINED A, C, AND E DOSE ON TYPE 2 DIABETIC PATIENTS

Objectives: This study is to investigate the effect of oral Vitamins combined (A, C, and E) with metformin on the levels of fasting blood sugar (FBS), postprandial blood sugar (PPBS), hemoglobin (HbA1c), total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) in Type 2 diabetic patients. Methods: A total of 32 patients with Type 2 diabetes were divided randomly into A and B groups, i.e., 16 per each group. Group A received metformin only twice a day while Group B received one tablet of Antox and metformin twice a day for 3 months. FBS, PPBS, HbA1c, TC, TG, LDL, and HDL were measured before and after the dose, and the results were analyzed statistically. Results: A significant decreases in FBS, PPBS, HbA1c, TC, TG, and LDL whereas results showed increasing significance in HDL level that seen in the patients of Group B which received Antox and metformin compared to the group which received metformin only. In conclusion, the results indicate that daily consumption of supplementary vitamins with metformin leads to improving blood glucose and lipids in patients with Type 2 diabetes and reducing the risk of complications. Hence, the dose can be used combined Vitamins A, C, and E with metformin in the treatment of Type 2 diabetes by maintaining good glycemic control

Taking forward a 'One Health' approach for turning the tide against the Middle East respiratory syndrome coronavirus and other zoonotic pathogens with epidemic potential

The appearance of novel pathogens of humans with epidemic potential and high mortality rates have threatened global health security for centuries. Over the past few decades new zoonotic infectious diseases of humans caused by pathogens arising from animal reservoirs have included West Nile virus, Yellow fever virus, Ebola virus, Nipah virus, Lassa Fever virus, Hanta virus, Dengue fever virus, Rift Valley fever virus, Crimean-Congo haemorrhagic fever virus, severe acute respiratory syndrome coronavirus, highly pathogenic avian influenza viruses, Middle East Respiratory Syndrome Coronavirus, and Zika virus. The recent Ebola Virus Disease epidemic in West Africa and the ongoing Zika Virus outbreak in South America highlight the urgent need for local, regional and international public health systems to be be more coordinated and better prepared. The One Health concept focuses on the relationship and interconnectedness between Humans, Animals and the Environment, and recognizes that the health and wellbeing of humans is intimately connected to the health of animals and their environment (and vice versa). Critical to the establishment of a One Health platform is the creation of a multidisciplinary team with a range of expertise including public health officers, physicians, veterinarians, animal husbandry specialists, agriculturalists, ecologists, vector biologists, viral phylogeneticists, and researchers to co-operate, collaborate to learn more about zoonotic spread between animals, humans and the environment and to monitor, respond to and prevent major outbreaks. We discuss the unique opportunities for Middle Eastern and African stakeholders to take leadership in building equitable and effective partnerships with all stakeholders involved in human and health systems to take forward a 'One Health' approach to control such zoonotic pathogens with epidemic potential