Ensemble modelling framework for groundwater level prediction in urban areas of India

India is facing the worst water crisis in its history and major Indian cities which accommodate about 50% of its population will be among highly groundwater stressed cities by 2020. In past few decades, the urban groundwater resources declined significantly due to over exploitation, urbanization, population growth and climate change. To understand the role of these variables on groundwater level fluctuation, we developed a machine learning based modelling approach considering singular spectrum analysis (SSA), mutual information theory (MI), genetic algorithm (GA), artificial neural network (ANN) and support vector machine (SVM). The developed approach was used to predict the groundwater levels in Bengaluru, a densely populated city with declining groundwater water resources. The input data which consist of groundwater levels, rainfall, temperature, NOI, SOI, NIÑO3 and monthly population growth rate were pre-processed using mutual information theory, genetic algorithm and lag analysis. Later, the optimized input sets were used in ANN and SVM to predict monthly groundwater level fluctuations. The results suggest that the machine learning based approach with data pre-processing predict groundwater levels accurately (R > 85%). It is also evident from the results that the pre-processing techniques enhance the prediction accuracy and results were improved for 66% of the monitored wells. Analysis of various input parameters suggest, inclusion of population growth rate is positively correlated with decrease in groundwater levels. The developed approach in this study for urban groundwater prediction can be useful particularly in cities where lack of pipeline/sewage/drainage lines leakage data hinders physical based modelling

Effective E-mail Communication for Optimization of Time and Cost in EPC Projects as Intellectual Property Management

E-mails are one of the most frequently used and authentic means of communication during engineering and design phase of various EPC projects. An effective e-mail communication can positively impact the cost and schedule of project deliverables. In this work, we studied various factors which affect quality and flow of mails in various disciplines of engineering design. Some of those factors are: number of senders/recipients, trailing mails, attachments, subject and main body of e-mail. Good management of e-mails and its folders at personal level can be helpful to prepare work plans and to set priorities of actions to be taken by individuals. It has also been mentioned that how e-mails can be considered and managed as an Intellectual Property Asset of project (or client) like other documents and standards

A new classification of inferior vena cava thrombus in renal cell carcinoma could define the need for cardiopulmonary or venovenous bypass

Introduction: Although the level of inferior vena cava (IVC) thrombus governs the type of surgical approach, there is no consistency in reporting the levels of IVC thrombus in the literature. This prospective study illustrates a simple three-level classification based on the need for clamping hepatoduodenal ligament and venovenous or cardiopulmonary bypass. Materials and Methods: Between January 2010 and June 2014, 30 patients of renal mass with renal vein and/or IVC thrombus were treated after classifying the IVC thrombus into three levels on the basis of need for clamping the hepatoduodenal ligament. After excluding renal vein thrombi, level I was described as thrombus located caudal to the hepatic vein. Level II included all retrohepatic, suprahepatic infradiaphragmatic or supradiaphragmatic thrombi reaching till the right atrium. Atrial thrombi were categorized as level III. Level I and II thrombi were managed without venovenous or cardiopulmonary bypass. Level III thrombus required cardiopulmonary bypass. Results: Of 26 patients with thrombus, 13 had level I thrombus. Of eight cases with level II thrombus, three were retrohepatic, three were suprahepatic infradiaphragmatic and two were supradiaphragmatic. All were removed successfully. Of five patients with level III thrombus, three were operated with cardiopulmonary bypass while the remaining two patients were too sick to be taken up for surgery. The median hepatoduodenal ligament clamp time was 10 min. One patient with level II thrombus had transient liver enzyme elevation. Conclusion: Renal vein thrombus should not be categorized as level I thrombus. Level II thrombus, irrespective of its relation to the diaphragm, could be managed without venovenous or cardiopulmonary bypass

An audit of early complications of radical cystectomy using Clavien-Dindo classification

Introduction: Despite the major improvements in surgical technique and perioperative care, radical cystectomy (RC) remains a major operative procedure with a significant morbidity and mortality. The present study analyzes the early complications of RC and urinary diversion using a standardized reporting system. Materials and Methods: Modified Clavien-Dindo classification was used to retrospectively assess the peri-operative course of 212 patients who had RC with urinary diversion between October 2003 and October 2014 at a single institution. The indications for surgery were muscle invasive urothelial carcinoma, high-grade nonmuscle invasive bladder cancer (BC), and Bacillus Calmette-Guerin-resistant nonmuscle invasive BCs. Data on age, sex, comorbidities, smoking history, American Society of Anaesthesiologists score, and peri-operative complications (up to 90 days) were captured. Statistical analysis was performed using SPSS 20.0 software (Chicago, USA). Results: The mean age was 56.15 ΁ 10.82. Orthotopic neobladder was created in 113 patients, ileal conduit in 88 patients, and cutaneous ureterostomy in 11 patients. A total of 292 complications were recorded in 136/212 patients. 242 complications (81.16%) occurred in the first 30 days, with the remaining 50 complications (18.83%) occurring thereafter. The rates for overall complication were 64.1%. The most common complications were hematologic (21.6%). Most of the complications were of Grade I and II (22.9% and 48.9%, respectively). Grade IIIa, IIIb, IVa, IVb, and V complications were observed in 10.2%, 8.9%, 3.4%, 2.7%, and 2.7% of the patients, respectively. Conclusions: RC and urinary diversion are associated with significant morbidity. This audit would help in setting a benchmark for further improvement in the outcome

Spiral laminar flow, the earliest predictor for maturation of arteriovenous fistula for hemodialysis access

Introduction: Arteriovenous fistula (AVF) is the gold standard vascular access for hemodialysis (HD). A thrill or murmur immediately after creation of AVF is considered a predictive sign of success. However, this does not ensure final maturation for successful HD. Our objective was to determine different clinical and duplex parameters within AVF to predict maturation and subsequent successful HD. Materials and Methods: A prospective observational study was conducted on 187 patients who had AVF formation from July 2012 to May 2013. Following surgery, all patients had Doppler ultrasound (DU) on Days 0 and 7. Doppler parameters noted in the outflow vein were: Thrill, broadening of spectral waveform with increased peak systolic velocity (PSV) and spiral laminar flow (SLF). Patients with at least one positive parameter at Day 0 were followed-up serially and underwent repeat Doppler imaging on Day 7. Patients with the absence of all three parameters on Day 0 were excluded from the study. Endpoint was maturation of AVF, i.e. successful HD. Statistical analysis was performed with binary logistic regression, to find out the strongest and earliest predictor for maturation of AVF using SPSS version 20. Results: SLF and broadening of spectral waveform with increased PSV were found to have a significant association with maturation (P = 0.0001). Presence of SLF on Day 0 most strongly predicted maturation. Presence of thrill or murmur could not predict the maturation. Conclusions: SLF pattern in AVF is the most important and the earliest predictor of maturation

Follow-up imaging after pediatric pyeloplasty

Introduction: The duration, methods and frequency of radiographic follow-up after pediatric pyeloplasty is not well-defined. We prospectively evaluated a cohort of children undergoing pyeloplasty to determine the method for follow-up. Methods: Between 2000 and 2008, children undergoing pyeloplasty for unilateral ureteropelvic junction obstruction were evaluated for this study. All patients were evaluated preoperatively with protocol ultrasound (USG) and diuretic renal scan (RS). On the basis of preoperative split renal function (SRF), these patients were divided into four groups - Group I: SRF > 40%, Group II: SRF 30–39%, Group III: SRF 20–29%, and Group IV: SRF 10–19%. In follow-up, USG and RS were done at 3 months and repeated at 6 months, 1 year, and then yearly after surgery for a minimum period of 5 years. Improvement, stability, or worsening of hydronephrosis was based on the changes in anteroposterior (AP) diameter of pelvis and caliectasis on USG. Absolute increase in split renal function (SRF) >5% was considered significant. Failure was defined as increase in AP diameter of pelvis and decrease in cortical thickness on 3 consecutive USG, t½ >20 min with obstructive drainage on RS and/or symptomatic patient. Results: 145 children were included in the study. Their mean age was 3.26 years and mean follow-up was 7.5 years. Pre- and post-operative SRF remain unchanged within 5% range in 35 of 41 patients (85%) in Group I. While 9 of 20 patients (45%) in Group II, 23 of 50 patients (46%) in Group III, and 14 of 34 patients (41%) in Group IV exhibited changes >5% after surgery. 5 patients failed, 2 in Group III, and 3 in Group IV. None of the patients deteriorated in Group I and II. Conclusion: After pyeloplasty in children with a baseline split GFR >30%, if a diuretic renogram and USG performed 3 months postoperatively shows nonobstructive drainage with t½ <20 min and decreased hydronephrosis, no further follow-up is required

Management of venous hypertension following arteriovenous fistula creation for hemodialysis access

Introduction: Venous hypertension (VH) is a distressing complication following the creation of arteriovenous fistula (AVF). The aim of management is to relieve edema with preservation of AVF. Extensive edema increases surgical morbidity with the loss of hemodialysis access. We present our experience in management of VH. Methods: A retrospective study was conducted on 37 patients with VH managed between July 2005 to May 2014. Patient demographics, evaluation, and procedures performed were noted. A successful outcome of management with surgical ligation (SL), angioembolization (AE), balloon dilatation (BD) or endovascular stent (EVS) was defined by immediate disappearance of thrill and murmur with resolution of edema in the next 48-72 h, no demonstrable flow during check angiogram and resolution of edema with preservation of AVF respectively. Results: All 8 distal AVF had peripheral venous stenosis and were managed with SL in 7 and BD in one patient. In 29 proximal AVF, central and peripheral venous stenosis was present in 16 and 13 patients respectively. SL, AE, BD, and BD with EVS were done in 18, 5, 4, and 3 patients, respectively. All patients had a successful outcome. SL was associated with wound related complications in 11 (29.73 %) patients. A total of 7 AVF were salvaged. One had restenosis after BD and was managed with AE. BD, EVS, and AE had no associated morbidity. Conclusions: Management of central and peripheral venous stenosis with VH should be individualized and in selected cases it seems preferable to secure a new access in another limb and close the native AVF in edematous limb for better overall outcome