74 research outputs found
Cost Recoverable Tariffs to Increase Access to Basic Services among Poor Households
The design of alternative tariff structures can serve as a low-cost and effective tool in achieving higher take-up of basic services among poor households while allowing the provider to recover costs. A contingent valuation survey from the Water Supply and Sanitation Project of the Asian Development Bank in Cebu, Philippines is used to show that tariff structures with a low one-time connection price and price differentiates based on wealth measures can result in a five-fold increase in the take-up of water services by poor households over the base tariff structure. More moderate impacts, however, are found for the take-up of new sanitation and sewage services
Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses
To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely
Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses
To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely
Battery-Free UHF-RFID Sensors-Based SLAM for In-Pipe Robot Perception
Water utilities across the globe are concerned with the inspection and replacement of buried metallic water pipes due to corrosion-related structural damages. Internal pipe linings are commonly used as a renewal method to improve structural strength as they are regarded to be a less expensive alternative to costly and time-consuming pipe replacements. However, linings are also prone to failure as well. Therefore, water authorities regularly monitor lining performance, where defect evolution over a long period of time is an important parameter to note. It requires an accurate in-pipe robot localization technology. In this article, we propose a novel method for in-pipe robot localization and tag mapping that uses battery-free ultra high frequency (UHF)-radio-frequency identification (RFID) sensor wireless signals. It utilizes a signal mapping approach in combination with a tailored pose-graph simultaneous localization and mapping (SLAM) algorithm. Evaluation results of a field-extracted pipe sample from Sydney Water's distribution network show that the proposed approach is capable of localizing the robot within 2.5 cm accuracy in a 50-m equivalent pipe with an unknown UHF-RFID distribution. The proposed approach outperformed other reported similar work in the literature
A Novel UHF-RFID Dual Antenna Signals Combined with Gaussian Process and Particle Filter for In-pipe Robot Localization
Condition assessment of underground infrastructures such as pipe networks is crucial for aging cities around the globe. The development of robotic technologies over the years led to the application of them in the condition assessment of pipe networks. However, there is a gap for accurate localization technology due to the complexity of the environment. In this letter, we propose a novel ultra-high frequency radio frequency identification (UHF-RFID) technology dual antenna system combined with Gaussian process and Particle filter algorithms to achieve millimetre level localization accuracy. The system is capable of achieving millimetre level accuracy over 50m of length without an apparent estimation drift. The results were validated through experiments conducted using an extracted water pipe section
Evaluation of Battery-free UHF-RFID Sensor Wireless Signals for In-pipe Robotic Applications
A reliable robotic localization method is required for comparing three-dimensional pipe maps obtained via laser scans at various times for accurately monitoring the evolution of internal pipe surface defects. Existing robotic localization methods have limitations when visual features vanish due to changes in the pipe environment or when encoder data becomes highly uncertain due to long-distance robotic traverses. To address this issue, we leverage battery-free ultra-high frequency radio frequency identification (UHF-RFID) sensors for transmitting wireless signals to a two-antenna reader integrated mobile robotic system. Although there are literature on the investigation of UHF- RFID behaviors and their applications in indoor environments, analysis of the same for in-pipe scenarios was not well studied. In this paper, we evaluate the UHF-RFID sensor signals inside a field extracted pipeline. Firstly, we examine the UHF-RFID sensor signal patterns through repeated robotic scans. Secondly, we examine how the placement of UHF-RFID reader antennas affects the transmission of UHF-RFID sensor signals, as well as we study the effects of robotic traverse direction and speed on the UHF-RFID wireless signals. Finally, we examine whether identical UHF-RFID sensors generate the same pattern when placed in a pipeline. Overall, the experimental evaluation demonstrates that the use of two-antenna UHF-RFID readers can ameliorate the capabilities of robotic localization in the pipeline
Quality of surface and ground waters for domestic and irrigation purposes in CKD/CKDu prevalent areas in Moneragala District, Sri Lanka
Total of 152 water samples from CKD/CKDu endemic areas and 30 water samples from non-CKDu prevalent areas in the Moneragala District were collected separately. pH values of water samples varied from 5.04 to 8.37 which are within the permissible limit prescribed by World Health Organization. More than 15% of water samples showed low Dissolved Oxygen (DO) values indicating heavy contamination by organic matter. Electrical conductivity was high ranging between 32 and 2865 μS/cm indicating higher mineralization in groundwater. The major ion chemistry reveals that the array of abundance of cations was variable as Na+ > Ca2+ > Mg2+ > K+ in dug wells, Ca2+ > Na+ > Mg2+ > K2+ in tube wells and Ca2+> Na+ > K+> Mg2+ in surface waters, while anions varied as HCO3->Cl->SO42->F- in water samples in both seasons. Computed WQI, 43%, 33%, and 82% for dug wells, tube wells and surface water respectively were in good water quality in this area, while waters in 30% and 25% of dug and tube wells respectively exceeded the value of 100 showing not suitable category. Considering irrigation quality, 88%, 93% and 96% of dug, tube and surface waters respectively were less than the permissible level. SAR values in the study area ranged from 0.08 to 4.91 meq/L by showing no danger of sodium as per SAR. The bulk of studied waters are appropriate for irrigation according to Residual Sodium Carbonate (RSC). Considering KR and PI, majority of water samples of the study area are suitable for irrigation purposes
- …