Contact lens-based microchannel rings for detecting ocular hypertension

Glaucoma is a major cause of irreversible blindness worldwide. The most acknowledged biomarker to diagnose and monitor glaucoma progression is intraocular pressure (IOP). Gold standard techniques for IOP monitoring are invasive, uncomfortable, and require visiting a clinic. In addition, most methods only provide a single snapshot on widely varying parameters. On the other hand, contact lenses have attracted particular interest to be used as continuous monitoring platforms to incorporate sensors, drugs, and more. Here, commercial contact lenses were laser-processed to be capable of detecting IOP variations in the physiological range. Three ring-couples with interspaces of 1.0, 1.5, and 2.0 mm were engraved on three soft contact lenses separately by using a carbon dioxide laser. The IOP/pressure variations induced repeatable changes in the ring-couple interspace which acted as a smartphone-readable pressure sensor. The processed contact lenses may be a potential candidate toward IOP monitoring at point-of-care settings

Optical glucose sensors based on hexagonally-packed 2.5-dimensional photonic concavities imprinted in phenylboronic acid functionalized hydrogel films

Continuous glucose monitoring aims to achieve accurate control of blood glucose concentration to prevent hypo/hyperglycaemia in diabetic patients. Hydrogel-based systems have emerged as a reusable sensing platform to quantify biomarkers in high-risk patients at clinical and point-of-care settings. The capability to integrate hydrogel-based systems with optical transducers will provide quantitative and colorimetric measurements via spectrophotometric analyses of biomarkers. Here, we created an imprinting method to rapidly produce 2.5D photonic concavities in phenylboronic acid functionalized hydrogel films. Our method exploited diffraction properties of hexagonally-packed 2.5D photonic microscale concavities having a lattice spacing of 3.3 μm. Illumination of the 2.5D hexagonally-packed structure with a monochromatic light source in transmission mode allowed reversible and quantitative measurements of variation in the glucose concentration based on first order lattice interspace tracking. Reversible covalent phenylboronic acid coupling with cis-diols of glucose molecules expanded the hydrogel matrix by ∼2% and 34% in the presence of glucose concentrations of 1 mM and 200 mM, respectively. A Donnan osmotic pressure induced volumetric expansion of the hydrogel matrix due to increasing glucose concentrations (1–200 mM), resulted in a nanoscale modulation of the lattice interspace, and shifted the diffraction angle (∼45° to 36°) as well as the interspacing between the 1st order diffraction spots (∼8 to 3 mm). The sensor exhibited a maximum lattice spacing diffraction shift within a response time of 15 min in a reversible manner. The developed 2.5D photonic sensors may have application in medical point-of-care diagnostics, implantable chips, and wearable continuous glucose monitoring devices

Overview on Epidemiology and Management of Myxedema Coma or Crisis

The most severe type of hypothyroidism is known as myxedema coma, which can quickly lead to death if not identified and treated aggressively. The condition known as hypothyroidism is easily detected and treated. But if ignored, it might eventually progress to myxedema coma, the most serious form of hypothyroidism. Since the majority of patients do not initially appear in a coma, the term "myxedema coma" is usually regarded as misleading. Lethargy usually progresses to stupor, which then becomes a coma with hypothermia and respiratory failure. only clinical criteria are used for diagnosis because thyroid hormone assays are unable to distinguish between simple hyperthyroidism and thyroid storm. Apart from essential medical interventions, the treatment focuses on preventing thyroid hormone production and secretion as antithyroid medications, and preventing the peripheral effects of thyroid hormone as β-blocker, glucocorticoids. The diagnosis of thyroid-stimulating hormone (TSH) in the blood is the same as that of simple hypothyroidism. As soon as a diagnosis is obtained, treatment should start right away. The majority of hospital and commercial laboratories can turnaround a TSH test in a matter of hours

عن نظرية السلطة في الإسلام : دراسة في مفهوم السلطة السياسية ومصادرها والقيود الواردة عليها في الفكر الإسلامي

علم النظرية السياسية من العلوم التي لم تنل ذلك القسط الوافي من البحث داخل مجال العلوم السياسية - وخاصة في ما يتعلق بالتراث الإسلامي - من المختصين في المجالين معاً ( الفقه والعلوم السياسية ) ، فهناك الكثير من الدارسات السياسية المحضة حول هذا الموضوع وهناك الكثير من الدراسات الفقهية التأصيلية ، لكن الصورة لا تتضح دون بناء نموذج يعتمد على كل المنهجين ، إذ إنها – أي النظرية السياسية الإسلامية – مبنية عليهما معاً . وهذا الكتاب هو مقاربة بحثية أصلها رسالة ماجستير في مجال النظرية السياسية نحاول من خلالها استيعاب السياق التاريخي لنشوء أو تبلور مفهوم السلطة السياسية داخل السياق الإسلامي من خلال الرجوع لعصر التكوين ، وسنمر في الكتاب على تطور المفهوم وتوابعه في الحضارة الغربية من اليونان وحتى مجموعة العقد الاجتماعي تاركين العصور الحديثة في كلا السياقين الأوروبي والإسلامي لدراسة أخرى . ثم ننتقل لبحث مصادر تلك السلطة مفرقين في هذا السياق بين السلطة من حيث هي قدرة على الإجبار والقهر ، والسلطة ذات الأحقية فيما اصطلح على تسميته لاحقاً بالشرعية . ونختم بالكلام عن القيود الواردة على السلطة السياسية ومصادر تلك القيود وطبيعتها بشكل مختصر . اتنبع أهمية الكلام عن هذا الموضوع في ذلك العصر من شرعية الخلفاء الأربعة في الفكر السياسي الإسلامي ، من حيث كون السلوك السياسي الصادر عنهم أو تحت علمهم يعتبر جزءً لا يتجزء من المنظومة السياسية التي أثرت وما زالت تؤثر على الدول التي تتبع هذا النوع من الفكر أو السلوك ، وآمل أن يكون هذا البحث خطوة على طريق تحديد معالم النظرية السياسية العامة للفكر الإسلامي في ظل هذه الأجواء المشحونة في الدول العربية والإسلامية والعالم أجمع

Optical hydrogel detector for pH measurements

Measuring pH has become a major key for determining health conditions, and food safety. The traditional pH assessment approaches are costly and offer low sensitivity. Here, a novel pH sensor based on a pH-responsive hydrogel has been developed. A Fresnel lens pattern was replicated on the surface of the pH-responsive hydrogel using the replica mould method. The pH sensors were tested in a pH range of 4–7. Introducing various pH solutions to the pH sensor led to volumetric shifts as the hydrogel swelled with pH. Consequently, the dimensions of the replicated Fresnel lens changed, modifying the focal length and the focus efficiency of the optical sensor. As a result, the measured optical power at a fixed distance from the sensor changed with pH. The optical sensor showed the best performance in the acidic region when pH changed from 4.5 to 5.5, in which the recorded power increased by 13%. The sensor exhibited high sensitivity to pH changes with a short respond time in a reversible manner. The developed pH optical sensor may have applications in medical point-of-care diagnostics and wearable continuous pH detection devices

Antioxidant Activity of <i>Moringa oleifera</i> and Olive <i>Olea europaea</i> L. Leaf Powders and Extracts on Quality and Oxidation Stability of Chicken Burgers

Oxidation is the main cause of quality deterioration in meat-based foods, such as burgers. Antioxidants inhibit the oxidation process; recently, natural antioxidants have gained interest, due to safety concerns. In this study, the effects of leaf powder and crude extracts of both Moringa oleifera and olive in chicken burgers were studied for their antioxidant potential in preventing fat oxidation during storage. Antioxidant activities were evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl). The results showed the highest DPPH radical scavenging with IC50 values of 2.397 ± 0.10 mg/mL in the Moringa leaf. Total phenolic content (TPC) was crude olive extract > crude Moringa extract > olive leaf > Moringa leaf. The total flavonoid content (TFC) was significantly higher in the olive leaf and its crude extract than in the Moringa leaf and its crude extract. The pH, total volatile nitrogen, and sensory properties were affected by the addition of olive and Moringa (leaf and crude extracts) to chicken burgers refrigerated for 20 days. The addition of Moringa and olive leaf powder decreased lipid oxidation and PV after 10 days of storage. In general, Moringa and olive leaf treatments slowed the deterioration of meat, suggesting their use as preservatives to extend the shelf-life of chicken burgers