Stokesian dynamic simulations and analyses of interfacial and bulk colloidal fluids

Understanding dynamics of colloidal dispersions is important for several applications ranging from coatings such as paints to growing colloidal crystals for photonic bandgap materials. The research outlined in this dissertation describes the use of Monte Carlo and Stokesian Dynamic simulations to model colloidal dispersions, and the development of theoretical expressions to quantify and predict dynamics of colloidal dispersions. The emphasis is on accurately modeling conservative, Brownian, and hydrodynamic forces to model dynamics of colloidal dispersions. In addition, we develop theoretical expressions for quantifying self-diffusion in colloids interacting via different particle-particle and particle-wall potentials. Specifically, we have used simulations to quantitatively explain the observation of anomalous attraction between like-charged colloids, develop a new criterion for percolation in attractive colloidal fluids, and validate the use of analytical expressions for quantifying diffusion in interfacial colloidal fluids. The results of this work contribute to understanding dynamics in interfacial and bulk colloidal fluids

Sonographic detection of umbilical cord presentation before induction of labor or labor admission: Presentation of 4 cases

Umbilical cord prolapse is a serious obstetric emergency that endangers the life of the baby. Perinatal mortality is as high as 44% when it occurs  outside a well‑equipped hospital. Women with malpresentations and positions, multifetal pregnancies, and polyhydramnios are at risk of developing this complication. Detection of cord presentation by transvaginal sonography before induction of labor, or at the time of labor admission, can prevent this potentially fatal obstetric emergency. We present successfully managed four cases of cord presentation at our institution. Key words: Cord presentation; cord prolapse; induction of labour; trans‑ vaginal sonography

A case of Couvelaire uterus with coagulation dysfunction saved successfully with SR PPH suction cannula

Couvelaire uterus is one of the complications associated with placental abruption, and the incidence is around 1%. Blood seeps into the uterine  musculature and reaches beneath the serosa. The uterus shows the signs of ecchymosis, flabby, cannot contract and retract and results in atonic post partum hemorrhage (PPH). As this uterus likely to bleed in postoperativee period, the treatment of choice is obstetric hysterectomy. In such cases, the women lose their fertility function. In this case, we have successfully used samartha ram post partum hemorrhage (SR PPH) suction cannula to achieve contraction and retraction and saved the uterus. Key words: Couvelaire uterus; SR PPH Suction cannula; Coagulation dysfunction

DRSP : Dimension Reduction For Similarity Matching And Pruning Of Time Series Data Streams

Similarity matching and join of time series data streams has gained a lot of relevance in today's world that has large streaming data. This process finds wide scale application in the areas of location tracking, sensor networks, object positioning and monitoring to name a few. However, as the size of the data stream increases, the cost involved to retain all the data in order to aid the process of similarity matching also increases. We develop a novel framework to addresses the following objectives. Firstly, Dimension reduction is performed in the preprocessing stage, where large stream data is segmented and reduced into a compact representation such that it retains all the crucial information by a technique called Multi-level Segment Means (MSM). This reduces the space complexity associated with the storage of large time-series data streams. Secondly, it incorporates effective Similarity Matching technique to analyze if the new data objects are symmetric to the existing data stream. And finally, the Pruning Technique that filters out the pseudo data object pairs and join only the relevant pairs. The computational cost for MSM is O(l*ni) and the cost for pruning is O(DRF*wsize*d), where DRF is the Dimension Reduction Factor. We have performed exhaustive experimental trials to show that the proposed framework is both efficient and competent in comparison with earlier works.Comment: 20 pages,8 figures, 6 Table

Intravenous isotonic fluid challenge, and L-arginine infusion for oligoamnios and diminished fetal movements: a preliminary study

Background: Utero-placental insufficiency is one of the major causes of oligoamnios and diminished fetal movements (FM). Rapid intravenous isotonic fluid infusion within the cardiovascular reserve improves tissue perfusion in all systems. We tested the hypothesis that isotonic fluid challenge may improve uteroplacental perfusion, which may, in turn improve fetal oxygenation, liquor formation, and FM.Methods: In this descriptive study, twenty-three antenatal mothers with gestational age >26 weeks, and with amniotic fluid index (AFI) <8 cm were included. Intravenous isotonic fluid challenge with 2 or 3 pints of ringer’s lactate, at the rate of 180-200 drops/minute, twice daily for 2-3days and, L-arginine infusion, 300 ml/day alternate days for 2-3 doses were given. Women were advised to take more than 3 litres of water a day. AFI was recorded once daily for 5 days, and then biweekly. The fluid challenge was repeated whenever AFI diminished <8.00 cm. AFI and perceived FM were graded. Pregnancies were terminated when there was no response to fluid challenge. The trend of changes in AFI and FM grades, number of days pregnancies continued, and perinatal outcomes were recorded.Results: We noted recurrent fall in AFI after an initial arise in 20 women, which required recurrent fluid challenges. Pregnancies could be continued for 18±8.5 days (median±SD). Three women, with case of absent FM, reported FM within 1 hour after initiation of the fluid challenge. There were no perinatal deaths.Conclusions: Intravenous isotonic fluid challenge and L-arginine infusion, improves AFI and FM, and helps to prolong pregnancies towards viability

Outcomes of induction of labor with mature and premature amniotic fluid optical density (AFOD): A preliminary case control study

Background: Onset of spontaneous labor occurs on completion of fetal functional maturity at amniotic fluid optical density (AFOD) value 0.98 ± 0.27 (Mean ± SD). All three events occurring together at any time from 35 to 42 weeks indicate individual term for each fetus. Babies born with AFOD ≤0.40 are functionally premature and develop varying degrees of respiratory distress syndrome (RDS). In this study, we tested the hypothesis, labors with AFOD 0.98 ± 0.27 are functionally mature with well‑established labor cascades and may respond well t o induction. On the other hand, labors with AFOD ≤0.40 are functionally premature with poorly established labor cascades and may not respond well t o induction.Methods: In this gestational age and parity‑matched case control study, cases consisted of 36 uncomplicated singleton laboring women who delivered normally with premature (≤0.40) AFOD values. Controls consisted of 36 similar laboring women who delivered normally with mature AFOD (0.98 ± 0.27) values. Uncentrifuged fresh AF samples collected at amniotomy were used for OD measurement with colorimeter at 650 nm. Women were assigned to groups based on AFOD values. In both groups, labor was induced with vaginal T. Misoprostol 25 mcg 6 hourly up to 4 doses. Labor outcome measures; Bishop score at induction, induction‑ delivery intervals (IDI), induction failures, number of T. Misoprostol required, presence of fetal distress, RDS, and NICU admission days were recorded in both groups and compared.Results: Median Bishop scores at induction in cases and controls were 5.0 (IQR 4.25‑‑6), 7.0 (IQR 6‑‑8), respectively. Median IDI in cases and controls were 18 h (IQR 12.25‑‑21.5 h) and 7.0 h (IQR 5‑‑9.5 h), respectively. Number of induction failures in cases and controls were 8 and 0, respectively. Outcomes of Induction of labor with…. Statistically significant differences observed in all these outcomes between groups (P = 0.00) favoring inductions with mature AFOD.Conclusion: Labor induction with mature AFOD value was successful in all women with shorter IDI and with better perinatal outcomes.Keywords: Induction of labor; mature amniotic fluid optical density; premature amniotic fluid optical densit

Stokesian dynamic simulations and analyses of interfacial and bulk colloidal fluids

Understanding dynamics of colloidal dispersions is important for several applications ranging from coatings such as paints to growing colloidal crystals for photonic bandgap materials. The research outlined in this dissertation describes the use of Monte Carlo and Stokesian Dynamic simulations to model colloidal dispersions, and the development of theoretical expressions to quantify and predict dynamics of colloidal dispersions. The emphasis is on accurately modeling conservative, Brownian, and hydrodynamic forces to model dynamics of colloidal dispersions. In addition, we develop theoretical expressions for quantifying self-diffusion in colloids interacting via different particle-particle and particle-wall potentials. Specifically, we have used simulations to quantitatively explain the observation of anomalous attraction between like-charged colloids, develop a new criterion for percolation in attractive colloidal fluids, and validate the use of analytical expressions for quantifying diffusion in interfacial colloidal fluids. The results of this work contribute to understanding dynamics in interfacial and bulk colloidal fluids

Experimental Investigation of Biogas-Biodiesel Dual Fuel Combustion in a Diesel Engine

This study is an attempt at achieving diesel fuel equivalent performance from diesel engines with maximum substitution of diesel with renewable fuels. In this context the study has been designed to analyze the influence of B20 algae biodiesel as a pilot fuel in a biodiesel biogas dual fuel engine, and results are compared to those of biodiesel and diesel operation at identical engine settings. Experiments were performed at various loads from 0 to 100 % of maximum load at a constant speed of 1500 rpm. In general, B20 algae biodiesel is compatible with diesel in terms of performance and combustion characteristics. Dual fuel mode operation displays lower thermal efficiency and higher fuel consumption than for other fuel modes of the test run across the range of engine loads. Dual fuel mode displayed lower emissions of NOx and Smoke opacity while HC and CO concentrations were considerably higher as compared to other fuels. In dual fuel mode peak pressure and heat release rate were slightly higher compared to diesel and biodiesel mode of operation for all engine loads