Corrosion study of pipeline material for seabed sediment in tropical climate

Corrosive environments such as marine sediments can cause corrosion to steel pipelines at any time when certain conditions are met. Seabed sediment could cause severe corrosion damage due to its corrosiveness to the pipelines buried under it. Many consequences could take place in case if there is incident in oil/gas pipelines. Successfully identifying elements of corrosion in marine sediment would enhance the future of steel structure protection and monitoring systems. This article focuses on the behaviour of corrosion rate of steel located near shore environment and the aim is to determine the effect of sediment on corrosion of steel. To investigate that, simulated near shore sediment conditions have been used where the steel coupons buried in sediments which have different characteristics. Weight loss technique has been implemented to determine the weight loss rate of the steel specimens. Based on the results of this study, metal weight loss increases as the duration of exposure to seabed sediment environment become longer. The sea sediment simulated condition has given significant levels of corrosion. Conclusively, the corrosion rate of steel in seabed sediment located in tropical region is complicated and further studies are suggested

Geostatistical upscaling of rain gauge data to support uncertainty analysis of lumped urban hydrological models

In this study we develop a method to estimate the spatially averaged rainfall intensity together with associated level of uncertainty using geostatistical upscaling. Rainfall data collected from a cluster of eight paired rain gauges in a 400 × 200m urban catchment are used in combination with spatial stochastic simulation to obtain optimal predictions of the spatially averaged rainfall intensity at any point in time within the urban catchment. The uncertainty in the prediction of catchment average rainfall intensity is obtained for multiple combinations of intensity ranges and temporal averaging intervals. The two main challenges addressed in this study are scarcity of rainfall measurement locations and non-normality of rainfall data, both of which need to be considered when adopting a geostatistical approach. Scarcity of measurement points is dealt with by pooling sample variograms of repeated rainfall measurements with similar characteristics. Normality of rainfall data is achieved through the use of normal score transformation. Geostatistical models in the form of variograms are derived for transformed rainfall intensity. Next spatial stochastic simulation which is robust to nonlinear data transformation is applied to produce realisations of rainfall fields. These realisations in transformed space are first back-transformed and next spatially aggregated to derive a random sample of the spatially averaged rainfall intensity. Results show that the prediction uncertainty comes mainly from two sources: spatial variability of rainfall and measurement error. At smaller temporal averaging intervals both these effects are high, resulting in a relatively high uncertainty in prediction. With longer temporal averaging intervals the uncertainty becomes lower due to stronger spatial correlation of rainfall data and relatively smaller measurement error. Results also show that the measurement error increases with decreasing rainfall intensity resulting in a higher uncertainty at lower intensities. Results from this study can be used for uncertainty analyses of hydrologic and hydrodynamic modelling of similar-sized urban catchments as it provides information on uncertainty associated with rainfall estimation, which is arguably the most important input in these models. This will help to better interpret model results and avoid false calibration and force-fitting of model parameters

Recurrence of intestinal metaplasia and early neoplasia after endoscopic eradication therapy for Barrett’s esophagus: A systematic review and meta-analysis

Abstract Background Conflicting data exist with regard to recurrence rates of intestinal metaplasia (IM) and dysplasia after achieving complete eradication of intestinal metaplasia (CE-IM) in Barrett’s esophagus (BE) patients. Aim (i) To determine the incidence of recurrent IM and dysplasia achieving CE-IM and (ii) to compare recurrence rates between treatment modalities [radiofrequency ablation (RFA) with or without endoscopic mucosal resection (EMR) vs stepwise complete EMR (SRER)]. Methods A systematic search was performed for studies reporting on outcomes and estimates of recurrence rates after achieving CE-IM. Pooled incidence [per 100-patient-years (PY)] and risk ratios with 95 %CI were obtained. Heterogeneity was measured using the I 2 statistic. Subgroup analyses, decided a priori, were performed to explore heterogeneity in results. Results A total of 39 studies were identified (25-RFA, 13-SRER, and 2 combined). The pooled incidence of any recurrence was 7.5 (95 %CI 6.1 – 9.0)/100 PY with a pooled incidence of IM recurrence rate of 4.8 (95 %CI 3.8 – 5.9)/100 PY, and dysplasia recurrence rate of 2.0 (95 %CI 1.5 – 2.5)/100 PY. Compared to the SRER group, the RFA group had significantly higher overall [8.6 (6.7 – 10.5)/100 PY vs. 5.1 (3.1 – 7)/100 PY, P = 0.01] and IM recurrence rates [5.8 (4.3 – 7.3)/100 PY vs. 3.1 (1.7 – 4)/100 PY, P &lt; 0.01] with no difference in recurrence rates of dysplasia. Significant heterogeneity between studies was identified. The majority of recurrences were amenable to repeat endoscopic eradication therapy (EET). Conclusion The results of this study demonstrate that the incidence rates of overall, IM, and dysplasia recurrence rates post-EET are not inconsiderable and reinforce the importance of close surveillance after achieving CE-IM.</jats:p

Salinity changes in the estuary and the coastal sea adjacent to the portmouth at Cochin

The article deals with the details of salinity changes in the Cochin estuary and its influence and interrelations with the Vembanad lake

Cross sectional, qualitative thematic analysis of patient perspectives of disease impact in juvenile idiopathic arthritis-associated uveitis

BACKGROUND: Chronic health conditions in children can have a significant impact on their quality of life. The aim of this study was to explore the subjective experience of children and young people being treated for chronic, non-infectious uveitis associated with a systemic disease such as juvenile idiopathic arthritis. METHODS: A semi-structured interview was conducted with 10 children and young people aged between 6 and 18 years of age and their parents. RESULTS: Preliminary thematic analysis indicated that both the treatment and complications of the disorder have a significant impact on the quality of life and emotional well-being of patients, not only in terms of the discomfort experienced but also in perceptions of social isolation, anxiety and sense of injustice. CONCLUSION: This study shows that themes including "impact on school", "social factors" and "emotional reactions" are important domains influencing health-related quality of life (HRQoL) in children with chronic uveitis. Inclusion of questions relating to these domains should be considered in future uveitis-specific tools examining HRQoL in these patients

Improving understanding of the underlying physical process of sediment wash-off from urban road surfaces

Among the urban aquatic pollutants, the most common is sediment which also acts as a transport medium for many contaminants. Hence there is an increasing interest in being able to better predict the sediment wash–off from urban surfaces. The exponential wash-off model is the most widely used method to predict the sediment wash-off. Although a number of studies proposed various modifications to the original exponential wash-off equation, these studies mostly looked into one parameter in isolation thereby ignoring the interactions between the parameters corresponding to rainfall, catchment and sediment characteristics. Hence in this study we aim (a) to investigate the effect of rainfall intensity, surface slope and initial load on wash-off load in an integrated and systematic way and (b) to subsequently improve the exponential wash-off equation focusing on the effect of the aforementioned three parameters. A series of laboratory experiments were carried out in a full-scale setup, comprising of a rainfall simulator, a 1 m 2 bituminous road surface, and a continuous wash-off measuring system. Five rainfall intensities ranging from 33 to 155 mm/h, four slopes ranging from 2 to 16% and three initial loads ranging from 50 to 200 g/m 2 were selected based on values obtained from the literature. Fine sediment with a size range of 300–600 µm was used for all of the tests. Each test was carried out for one hour with at least 9 wash-off samples per test collected. Mass balance checks were carried out for all the tests as a quality control measure to make sure that there is no significant loss of sand during the tests. Results show that the washed off sediment load at any given time is proportional to initial load for a given combination of rainfall intensity and surface slope. This indicates the importance of dedicated modelling of build-up so as to subsequently predict wash-off load. It was also observed that the maximum fraction that is washed off from the surface increases with both rainfall intensity and the surface slope. This observation leads to the second part of the study where the existing wash-off model is modified by introducing a capacity factor which defines this maximum fraction. This capacity factor is derived as a function of wash-off coefficient, making use of the correlation between the maximum fraction and the wash-off rate. Values of the modified wash-off coefficient are presented for all combinations of rainfall intensities and surface slopes, which can be transferred to other urban catchments with similar conditions

Biotoxicity in Marine Organisms

The results from the screening of 118 marine organisms (corals, alcyoniarians, mollusks, echinoderms, flagellates) found in the coastal waters of India for their toxicity on fish and mice fingerlings as well as their hemolytic activities are presented

Android Application to Detect and Alert Tachycardia and Bradycardia using Pulse Rate Sensor

Heart rate monitoring is most vital in preventing disorders related to heart. Failure to detect heart disorder in early stage may lead to death. The lacking of devices to immediately detect the abnormalities in heart and alert the patients emergency contact lead to this problem. In this report the author propose a system to detect two heart disorders called Tachycardia and Bradycardia which are caused by abnormalities in heart rate. The proposed system will consist of a pulse sensor which will be connected to a smartphone via Bluetooth. The signal information which is processed by the microcontroller will be sent to the mobile phone. An app created will send an alert to the emergency contacts of the patients when Tachycardia or Bradycardia condition has been detected by the sensor. This will increase the possibilities of giving immediate treatment to the patient, and hope to reduce the death rate caused by heart disorder

Nicotine in the Endoplasmic Reticulum

Nicotine activates plasma membrane (PM) nicotinic receptors (nAChRs), but also permeates into the endoplasmic reticulum (ER) and cis-Golgi, and there binds to nascent nAChRs. Other psychiatric and abused drugs may also enter the ER and bind their classical targets. Further progress requires direct proof, quantification, and time resolution of these processes in live cells and in the brain of animals. Therefore, we are developing genetically encoded fluorescent biosensors to study the subcellular pharmacokinetics of neural drugs