9 research outputs found

    Immobilized photocatalyst on stainless steel woven meshes assuring efficient light distribution in a solar reactor

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    An immobilized TiO<sub>2</sub> photocatalyst with a high specific surface area was prepared on stainless steel woven meshes in order to be used packed in layers for water purification. Immobilization of such a complex shape needs a special coating technique. For this purpose, dip coating and electrophoretic deposition (EPD) techniques were used. The EPD technique gave the TiO<sub>2</sub> coating films a better homogeneity and adhesion, fewer cracks, and a higher <sup>·</sup>OH formation than the dip coating technique. The woven mesh structure packed in layers guaranteed an efficient light-penetration in water treatment reactor. A simple equation model was used to describe the distribution of light through the mesh layers in the presence of absorbing medium (e.g., colored water with humic acids). Maximum three or four coated meshes were enough to harvest the solar UV light from 300 nm to 400 nm with a high penetration efficiency. The separation distance between the mesh layers played an important role in the efficiency of solar light penetration through the coated mesh layers, especially in case of colored water contaminated with high concentrations of humic acid

    The Arab Spring: confronting the challenge of non-communicable disease.

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    This Commentary considers the health system and policy challenges of addressing non-communicable diseases (NCDs) in Egypt, Libya, and Tunisia, countries in the process of re-framing state policies and institutions, including in the health sector. Against this backdrop, a neglected issue of the rapidly rising burden of NCDs threatens both health and economic development. Tackling this worrisome rise in NCDs has been impeded by inadequate policies. Weak health systems, little attention to determinants of health, and limited access to affordable health care complicate effective responses to NCDs, especially in a fragile transitional phase. There remains an opportunity to confront the neglected challenge of NCDs by substantially strengthening policies and scaling up comprehensive health systems to more effectively address the causes and treatment of NCDs, including mental health, ultimately to improve population health overall

    Imaging of trigeminal neuralgia

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    Trigeminal neuralgia is one of the most frequent neuropathy of the cranial nerves, whose prevalence has been reported between 0.03% and 0.3% in the general population. This condition is a communal manifestation of several possible etiologies. The classical type of trigeminal neuralgia is defined as sudden, usually unilateral, severe, brief, stabbing recurrent episodes of pain in the distribution of one or more branches of the trigeminal nerve, with no cause other than a neurovascular compression. Secondary trigeminal neuralgia is the term used to group a large amount of different diseases, which are alike in developing the symptoms of trigeminal neuralgia, due to an insult to the V CN which triggers the complex pathogenesis of pain. These conditions include inflammatory diseases, infections, neoplasms, autoimmune diseases, vascular diseases other than neurovascular conflict, and treatment-related disorders. Generally, the possible mechanisms which lead to the development of neuralgia include nerve distortion/compression by an external mass or damage to the nerve fibers due to an acute or chronic insult. The radiological investigation plays a pivotal role in the diagnosis of trigeminal neuralgia, and MRI constitutes the gold imaging standard in most cases. The trigeminal nerve is a mixed sensory-motor nerve which can be divided anatomically into five segments: brainstem segment, cisternal segment, Meckel’s cave segment, cavernous sinus segment, and extracranial segment. In this paragraph, an anatomy-based imaging approach is proposed to investigate the many causes of trigeminal neuralgia, highlighting the importance of choosing the appropriate sequences and parameters, in the light of a target-suited protocol
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