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Objective: To assess the Frequency and the types of Posterior Capsular Opacification after extra capsular cataract extraction and posterior chamber intraocular lens (PMMA) implantation. Study Design: Descriptive study Place and Duration of Study: Department of Ophthalmology Holy Family Hospital, Rawalpindi from May 2003 to May 2005. Materials and Methods: Two hundred patients, with age ranges from 55 to 80 years, having uncomplicated senile mature cataracts who underwent ECCE with PCIOL over a period of one year were selected for the study. At 6th Month post operatively the patients were examined for any evidence of posterior capsular opacification with its type and the results were analyzed. Results: At 6 months follow up 70 patients (35%) developed posterior capsular opacification. Out of these 70 patients, 40 patients (57%) showed capsular fibrosis and 30 patients (43 %) Elschnig pearls. Conclusion: Our study revealed that the occurrence of posterior capsular opacification with PMMA intra ocular lens is high leading to significant number of patients with visually disabling complication in the post operative period.

This paper presents design, analysis, and characterization of a compliant non-linear electromagnetic energy harvester operating on the principle of bi-stability incorporated with a displacement amplification mechanism. The energy harvester engenders energy from ambient vibrations at multiple modes and with frequencies ranging from 80 to 120 Hz. The energy harvester is analytically modeled using the mechanic's elastic beam theory. Finite Element Analysis (FEA) has been carried out using commercial Finite Element Method (FEM) based software to perform static, fatigue, dynamic and electromagnetic analysis. Bi-stable mechanism has been used to harness energy at a wider frequency bandwidth while lever mechanism is acting as a displacement amplifier for enhancing low frequency vibration amplitude with the amplification factor of 6.24. With such amplification factor, the energy harvester can be deployed to extract vibrations of diminutive level and recast them into electrical energy in the form of generated voltage. Spring steel material, owing to its structural sensitivity, stiffness and higher value of ultimate stress, was used for its fabrication. The use of Neodymium (N52) magnets, copper coils and shaker were put into practice for testing of this device. The coil resistance is 2.5 Ω with number of turns kept at 350. The maximum output voltage of 1.86 V was generated at 106 Hz with root mean square value of 548 mV. Testing results are in accordance with the results obtained through simulations and thus useful electrical power of 11.1 mW can be generated from ambient vibrations at a wider bandwidth of 18 Hz with operating frequency ranging from 99 to 117 Hz. [ABSTRACT FROM AUTHOR]

Emerging nonthermal and thermal food processing technologies are a better alternative to conventional thermal processing techniques because they offer high-quality, minimally processed food. Texture is important in the food industry because it encompasses several product attributes and plays a vital role in consumer acceptance. Therefore, it is imperative to analyze the extent to which these technologies influence the textural attributes of food grains. Physical forces produced by cavitation are attributed to ultrasound treatment-induced changes in the conformational and structural properties of food proteins. Pulsed electric field treatment causes polarization of starch granules, damaging the dense outer layer of starch granules and decreasing the mechanical strength of starch. Prolonged radio frequency heating results in the denaturation of proteins and gelatinization of starch, thus reducing binding tendency during cooking. Microwave energy induces rapid removal of water from the product surface, resulting in lower bulk density, low shrinkage, and a porous structure. However, evaluating the influence of these techniques on food grain texture is difficult owing to differences in their primary operation mode, operating conditions, and equipment design. To maximize the advantages of nonthermal and thermal technologies, in-depth research should be conducted on their effects on the textural properties of different food grains while ensuring the selection of appropriate operating conditions for each food grain type. This article summarizes all recent developments in these emerging processing technologies for food grains, discusses their potential applications and drawbacks, and presents prospects for future developments in food texture enhancement. [ABSTRACT FROM AUTHOR]