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Background:Pregnancy induced hypertension, is the commonest form of life-threatening complications of pregnancy. Pregnancy is described as the only physiological state in which most physiological parameters are abnormal. The anatomical, physiological and biochemical adaptations that take place in a woman during the short span of human pregnancy are profound. Compared with normotensive gravidas, patients with elevated blood pressure have significantly greater maternal and foetal mortality and morbidity. The clinical and laboratory characteristics of hypertension associated with pregnancy are difficult to differentiate from those of hypertension independent of pregnancy. Objective:The objective of this study was to study the prevalence and risk factors of ocular fundus changes among pregnant women with PIH. Materials and Methods:A hospital‐based, cross‐sectional study was carried out among 130 pregnantwomen with PIH. History of symptoms related to the eyes, age, and gravida was recorded. Torchlight was used to examine the anterior segment. One percentage of tropicamide was used to dilate pupils. Direct ophthalmoscope was used to examine the fundus. Blood pressure was measured as per the standard guidelines. Urine sample was taken to look for the presence of proteins in urine. Results:The majority belonged to 18 to 35years (50%) and the majority (54.6%) had gestational age >37 weeks. The majority (75.38%) had gestational hypertension. The prevalence of retinopathy among pregnant women with PIH was 13.7% Grade I retinopathy was most commonly seen in 7.7% of cases followed by Grade II retinopathy in 2.7% of the cases, grade 3 in 1.4% and grade 4 in 0.6%. one patient had exudative retinal detachment. Age was not found to be associated with retinopathy among pregnant women with PIH. The prevalence of retinopathy among women with preeclampsia was 31.7% and in eclampsia was 40 %, compared to only 7.07% in women with gestational hypertension and this difference was statistically significant (P < 0.05). The prevalence of retinopathy among women with blood pressure >150/100 mmHg was 45.4% compared to only 2.6% in women with bloodpressure Conclusion:The prevalence of retinopathy among pregnant women with PIH was high. High blood pressure and severe proteinuria and preeclampsia were significantly associated with retinopathy. &nbsp

Background:The Static VAR Compensator (SVC) has the capability of improving reliability, operation and control of the transmission system thereby improving the dynamic performance of power system. SVC is a widely used shunt FACTS device, which is an important tool for the reactive power compensation in high voltage AC transmission systems. The transmission lines compensated with the SVC may experience faults and hence need a protection system against the damage caused by these faults as well as provide the uninterrupted supply of power.Methods:The research work reported in the paper is a successful attempt to reduce the time to detect faults on a SVC-compensated transmission line to less than quarter of a cycle. The relay algorithm involves two ANNs, one for detection and the other for classification of faults, including the identification of the faulted phase/phases. RMS (Root Mean Square) values of line voltages and ratios of sequence components of line currents are used as inputs to the ANNs. Extensive training and testing of the two ANNs have been carried out using the data generated by simulating an SVC-compensated transmission line in PSCAD at a signal sampling frequency of 1 kHz. Back-propagation method has been used for the training and testing. Also the criticality analysis of the existing relay and the modified relay has been done using three fault tree importance measures i.e., Fussell-Vesely (FV) Importance, Risk Achievement Worth (RAW) and Risk Reduction Worth (RRW).Results:It is found that the relay detects any type of fault occurring anywhere on the line with 100% accuracy within a short time of 4 ms. It also classifies the type of the fault and indicates the faulted phase or phases, as the case may be, with 100% accuracy within 15 ms, that is well before a circuit breaker can clear the fault. As demonstrated, fault detection and classification by the use of ANNs is reliable and accurate when a large data set is available for training. The results from the criticality analysis show that the criticality ranking varies in both the designs (existing relay and the existing modified relay) and the ranking of the improved measurement system in the modified relay changes from 2 to 4.Conclusion:A relaying algorithm is proposed for the protection of transmission line compensated with Static Var Compensator (SVC) and criticality ranking of different failure modes of a digital relay is carried out. The proposed scheme has significant advantages over more traditional relaying algorithms. It is suitable for high resistance faults and is not affected by the inception angle nor by the location of fault.