Pursuit on a Graph Using Partial Information

The optimal control of a "blind" pursuer searching for an evader moving on a road network and heading at a known speed toward a set of goal vertices is considered. To aid the "blind" pursuer, certain roads in the network have been instrumented with Unattended Ground Sensors (UGSs) that detect the evader's passage. When the pursuer arrives at an instrumented node, the UGS therein informs the pursuer if and when the evader visited the node. The pursuer's motion is not restricted to the road network. In addition, the pursuer can choose to wait/loiter for an arbitrary time at any UGS location/node. At time 0, the evader passes by an entry node on his way towards one of the exit nodes. The pursuer also arrives at this entry node after some delay and is thus informed about the presence of the intruder/evader in the network, whereupon the chase is on - the pursuer is tasked with capturing the evader. Because the pursuer is "blind", capture entails the pursuer and evader being collocated at an UGS location. If this happens, the UGS is triggered and this information is instantaneously relayed to the pursuer, thereby enabling capture. On the other hand, if the evader reaches one of the exit nodes without being captured, he is deemed to have escaped. We provide an algorithm that computes the maximum initial delay at the entry node for which capture is guaranteed. The algorithm also returns the corresponding optimal pursuit policy

A study of the role of intervention in the final outcome of acute pancreatitis

Background: Acute pancreatitis is a common disease which varies in severity, from mild self-limiting pancreatic inflammation to severe pancreatic necrosis with life-threatening sequelae. As per the recent recommendations early intensive care with delayed intervention and step-up approach when indicated has definite survival advantages over the risks associated with early surgical procedures. The present study was aimed at evaluating the mortality and morbidity risk in patients undergoing procedural intervention in acute pancreatitis.Methods: This was a prospective study done in Sri Ramachandra Medical College and Hospital from April 2012- September 2014. All patients with a diagnosis of acute pancreatitis were included in this study. A total of 110 patients were analysed. Routine lab parameters, serum amylase, lipase, lipid profile, calcium, CRP, LDH, CT abdomen, CXR and 2D Echo was done for all patients. Procedural intervention was planned as per the guidelines.Results: Patients were given early intensive care as per the initial severity scores. 25 patients required intervention. Serum LDH, amylase, lipase and CT severity index were better predictors of requirement of intervention and death. Open necrosectomy was done in 15 patients (13.6%), laparoscopic necrosectomy in 3 patients (2.7%) and step up approach was tried in 7 patients (6.4%). Patients who were tried step up approach were monitored closely for any deterioration in their clinical condition to decide about surgery. 7 out of 8 patients who underwent surgery died.  Alcoholic pancreatitis that underwent intervention had a high risk of mortality.Conclusions: Intensive care monitoring with delayed intervention had a better survival benefit. Patients subjected to minimally invasive interventions had a better chance of survival.

Scar endometriosis following hysterotomy: a case report

Scar endometriosis is a rare entity mostly following obstetrical and gynecological surgeries and difficult to diagnose. It is often misdiagnosed as abscess, suture granuloma or lipoma. We report a case of scar endometriosis following hysterotomy - because of its rarity

Vertical and horizontal gradients in aerosol black carbon and its mass fraction to composite aerosols over the east coast of peninsular India from aircraft measurements

During the Integrated Campaign for Aerosols, gases and Radiation Budget (ICARB) experiment of ISRO-GBP, altitude profiles of mass concentrations of aerosol black carbon (M) and total (composite) aerosols (M) in the lower troposphere were made onboard an aircraft from an urban location, Chennai (13.04 °N, 80.17 °E). The profiling was carried out up to 3 km (AGL) in eight levels to obtain higher resolution in altitude. Besides, to explore the horizontal gradient in the vertical profiles,measurements were made at two levels [500m (within ABL) and 1500m (above ABL)] from ~10 °N to 16°N and ~80 °E to 84°E. The profiles showed a significant vertical extent of aerosols over coastal and offshore regions around Chennai with BC concentrations (~2 μg m) and its contribution to composite aerosols remaining at the same level (between 8 to 10% for FBC) as at the surface. Even though the values are not unusually high as far as an urban location is concerned, but their constancy throughout the vertical column will have important implications to climate impact of aerosols

DELAMINATION PREDICTION IN DRILLING OF CFRP COMPOSITES USING ARTIFICIAL NEURAL NETWORK

Carbon fibre reinforced plastic (CFRP) materials play a major role in the applications of aeronautic, aerospace, sporting and transportation industries. Machining is indispensible and hence drilling of CFRP materials is considered in this present study with respect to spindle speed in rpm, drill size in mm and feed in mm/min. Delamination is one of the major defects to be dealt with. The experiments are carried out using computer numerical control machine and the results are applied to an artificial neural network (ANN) for the prediction of delamination factor at the exit plane of the CFRP material. It is found that ANN model predicts the delamination for any given set of machining parameters with a maximum error of 0.81% and a minimum error of 0.03%. Thus an ANN model is highly suitable for the prediction of delamination in CFRP materials

Burden of chikungunya in India: estimates of disability adjusted life years (DALY) lost in 2006 epidemic

Background & objectives: During 2006, chikungunya emerged as a major ever known epidemic in India. Disability adjusted life years (DALY) is an appropriate summary measure of population health to express epidemiological burden of diseases. We estimated the burden due to suspected chikungunya using DALYs for the first time and compared between the states and also with the burden due to other vector-borne diseases in India. The economic burden was also assessed in terms of productivity loss.Methods: Data on the reported cases of fever/suspected cases of chikungunya from different states during 2006 in India were used. Years lived with disability (YLD) were calculated for non-fatal cases to estimate DALY. Since the disability weight for chikungunya is not available, the weights available for rheumatic arthritis, comparable to the disease outcome of chikungunya were used for the estimation. The burden was estimated for both acute and chronic cases. It is considered that about 11.5% of cases were reported to have extended morbidity with persisting arthralgia. For acute disease, the average duration of illness was considered to be nine days and for chronic cases it was six months on an average. The productivity loss due to income foregone by the working class was calculated using minimum official wage.Results: National burden of chikungunya was estimated to be 25,588 DALYs lost during 2006 epidemic, with an overall burden of 45.26 DALYs per million. It varied from 0.01 to 265.62 per million in different states. Karnataka alone contributed as high as 55% of the national burden. Persistent arthralgia was found to impose heavy burden, accounting for 69% of the total DALYs. The productivity loss in terms of income foregone was estimated to be a minimum of Rs. 391 million. Interpretation & conclusion: The chikungunya epidemic in the year 2006 imposed heavy epidemiological burden and productivity loss to the community. The burden of chikungunya in terms of DALY was estimated for the first time. In view of re-emergence and spread of this infection in recent times it is warranted for derivation of disability weight for different health states of chikungunya to facilitate realistic estimates of DALYs. Quality epidemiological data from surveillance system to monitor vector-borne and zoonotic diseases would pave way for more realistic estimates of burden. The productivity loss in-terms of income foregone could be minimal as the estimation was made by using the minimum wage fixed by the government although the actual loss is expected to be higher