Senslide: a distributed landslide prediction system

We describe the design, implementation, and current status of Senslide, a distributed sensor system aimed at predicting landslides in the hilly regions of western India. Landslides in this region occur during the monsoon rains and cause significant damage to property and lives. Unlike existing solutions that detect landslides in this region, our goal is to predict them before they occur. Also, unlike previous efforts that use a few but expensive sensors to measure slope stability, our solution uses a large number of inexpensive sensor nodes inter-connected by a wireless network. Our system software is designed to tolerate the increased failures such inexpensive components may entail. We have implemented our design in the small on a laboratory testbed of 65 sensor nodes, and present results from that testbed as well as simulation results for larger systems up to 400 sensor nodes. Our results are sufficiently encouraging that we intend to do a field test of the system during the monsoon season in India

Exploring the physics of methane-foam generation for gas mobility control in high-temperature, proppant-fractured reservoirs

Gas EOR through HnP is an increasingly important method of recovering additional oil from fracture-stimulated reservoirs. HnP productivity, however, is hampered by well interference and fracture channeling leading to early gas breakthrough and poor areal sweep efficiency. To mitigate these issues and improve conformance control, foam-generating surfactants have been developed as a method of reducing mobility of the injected gas phase and increasing oil recovery. The experiments outlined in this work investigated foam generation and propagation by an anionic and amphoteric surfactant blend in high-temperature, high-pressure, high-permeability, and high-shear conditions meant to simulate the actual environment of a proppant-filled fracture. Bulk foam tests confirmed the aqueous stability and foaming viability of the surfactant at the proposed temperature, pressure, and salinity. Through several series of floods co-injecting methane gas and the surfactant solution through a proppant-pack at residual oil, the effects of several injection parameters on apparent foam viscosity were investigated. The surfactant exhibited an unusually high transition foam quality at about or greater than 95% as well as expected shear-thinning behavior. When analyzing the effect of pressure on foam generation, an important finding was observed in that foam viscosity linearly decreased with increasing pressure. Another flood series was conducted in an oil free proppant pack and showed that residual oil had no effect on the apparent foam viscosity, meaning oil swelling at higher pressures could not be the reason the inversely linear pressure trend was seen. An additional flood series with nitrogen as the injection gas was completed to see if the hydrophobic attraction between the methane and surfactant tail was responsible for the observed pressure trend, but, despite an increase in apparent foam viscosity, the pressure trend persisted even with nitrogen. Though a conclusion could not be made on the cause of the pressure dependency, previous tests confirmed that the trend is not the result of a system artifact and supported that it must be due to the effect of pressure on surface properties of foam film stabilized by this particular surfactant formulation. Additional tests focused on the effect of pressure on surfactant adsorption and micellar size could prove fruitful in finding an answer.Petroleum and Geosystems Engineerin

Impact of cytochrome P450 3A4 inducer and inhibitor on the pharmacokinetics of trabectedin in patients with advanced malignancies: open-label, multicenter studies

Purpose : To evaluate the pharmacokinetics, safety and survival of trabectedin, metabolized primarily by cytochrome P450 (CYP)3A4 enzyme, when coadministered with rifampin (CYP3A4 inducer) or ketoconazole (CYP3A4 inhibitor) in adult patients with advanced solid tumors. Methods : Two phase 1/2a, 2-way crossover studies were conducted. For rifampin study, 12 patients were randomized (1:1) to sequence of a cycle of trabectedin (1.3 mg/m2, 3 h, i.v.) coadministered with rifampin (600 mg/day, 6-days), and a cycle of trabectedin monotherapy (1.3 mg/m2, 3 h, i.v.). In ketoconazole study, eight patients were randomized (1:1) to sequence of a cycle of trabectedin (0.58 mg/m2, 3 h, i.v.) coadministered with ketoconazole (200 mg, twice-daily, 15-doses), and a cycle of trabectedin monotherapy (1.3 mg/m2, 3 h, i.v.). Results : The systemic exposure (geometric means) of trabectedin was decreased [22 % (C max) and 31 % (AUClast)] with rifampin coadministration and increased [22 % (C max) and 66 % (AUClast)] with ketoconazole coadministration. This correlated with an increased clearance with rifampin (39.6–59.8 L/h) and a decreased clearance with ketoconazole (20.3–12.0 L/h). Consistent with earlier studies, the most common (≥40 %) treatment-emergent adverse events in both studies were nausea, vomiting, diarrhea, hepatic function abnormal, anemia, neutropenia, thrombocytopenia and leukopenia. Conclusions : Coadministration of rifampin or ketoconazole altered the pharmacokinetics of trabectedin, but no new safety signals were observed. Coadministration of trabectedin with potent CYP3A4 inhibitors or inducers should be avoided if possible. If coadministration of trabectedin with a strong CYP3A4 inhibitor is required, close monitoring for toxicities is recommended, so that appropriate dose reductions can be instituted as warranted

Patient-reported outcomes in relapsed ovarian cancer : results from a randomized Phase III study of trabectedin with pegylated liposomal doxorubicin (PLD) versus PLD alone

Objective. Trabectedin in combination with PLD improves progression-free suivival (PFS) and overall response rate (ORR) in comparison to PLD alone in patients with relapsed ovarian cancer (J Clin Oncol; 2010 28:3107-14). Here we report the impact of the treatment combination on patient-reported functional status and symptoms. Methods. Patient-reported outcome (PRO) questionnaires, EORTC-QLQ C30, OV28, and EQ-5D were completed by patients at screening and on Day 1 of every other treatment cycle starting with Cycle 1, and at the end-of-treatment visit. Results. Of the 672 patients randomized in this study, 663 treated patients completed at least one of the baseline questionnaires. Median cycles of treatment was 6 (131 days) for the combination arm and 5 (143 days) for the monotherapy arm. Longitudinal data analyses showed no significant differences between the treatment arms for any of the pre-specified scales. Similar analyses of other scales, including Health Index scores and Health State on the Visual Analog Scale, support these findings. Start of subsequent therapy was significantly delayed in the combination arm compared with the monotherapy arm (p = 0.0032). Conclusions. The addition of trabectedin to PLD led to little or no decrement in patient-reported functional status and symptoms in patients with relapsed ovarian cancer, as compared to treatment with PLD alone. The combination led to manageable and non-cumulative overall toxicity with a fewer PLD-associated adverse events, and a significant improvement in PFS and ORR compared to single agent. (C) 2012 Elsevier Inc. All rights reserved

Trabectedin plus pegylated liposomal doxorubicin (PLD) versus PLD in recurrent ovarian cancer : overall survival analysis

Aim: Trabectedin in combination with pegylated liposomal doxorubicin (PLD) improves progression-free survival (PFS) compared to PLD alone in recurrent ovarian cancer (J Clin Oncol 2010; 28: 3107-14). Methods: Women, stratified by performance status (0-1 versus 2) and platinum sensitivity (platinum-free interval [PFI] < 6 versus >= 6 months), were randomly assigned to receive PLD 30 mg/m(2) IV followed by a 3-h infusion of trabectedin 1.1 mg/m(2) every 3 weeks or PLD 50 mg/m(2) every 4 weeks. The study was powered to show a 33% increase in overall survival (OS) after 520 deaths had occurred. Results: After a median follow-up of 47.4 months, there were 522 deaths among 672 subjects. The median OS for trabectedin + PLD and PLD arms was 22.2 and 18.9 months, respectively (hazard ratio [HR] = 0.86; 95% confidence interval [CI]: 0.72-1.02; p = 0.0835). An unexpected but significant imbalance in the PFI favouring the PLD arm (mean PFI: PLD = 13.3 months, trabectedin + PLD = 10.6 months) was identified. On the basis of this finding, an unplanned hypothesis generating analysis adjusting for the PFI imbalance and other prognostic factors suggested an improvement in OS associated with the trabectedin + PLD arm (HR = 0.82; 95% CI: 0.69-0.98; p = 0.0285). In another unplanned exploratory analysis, the subset of patients with a PFI of 6-12 months had the largest difference in OS (HR = 0.64; 95% CI: 0.47-0.86; p = 0.0027). Conclusions: The final OS analysis did not meet the protocol-defined criterion for statistical significance. Despite stratification on platinum sensitivity, there was an imbalance in mean platinum free interval that had an effect on OS. (C) 2012 Elsevier Ltd. All rights reserved