Low-cost monitoring systems for urban water management: Lessons from the field.

Sound urban water management relies on extensive and reliable monitoring of water infrastructure. As low-cost sensors and networks have become increasingly available for environmental monitoring, urban water researchers and practitioners must consider the benefits and disadvantages of such technologies. In this perspective paper, we highlight six technical and socio-technological considerations for low-cost monitoring technology to reach its full potential in the field of urban water management, including: technical barriers to implementation, complementarity with traditional sensing technologies, low-cost sensor reliability, added value of produced information, opportunities to democratize data collection, and economic and environmental costs of the technology. For each consideration, we present recent experiences from our own work and broader literature and identify future research needs to address current challenges. Our experience supports the strong potential of low-cost monitoring technology, in particular that it promotes extensive and innovative monitoring of urban water infrastructure. Future efforts should focus on more systematic documenting of experiences to lower barriers to designing, implementing, and testing of low-cost sensor networks, and on assessing the economic, social, and environmental costs and benefits of low-cost sensor deployments.

End-user perspective of low-cost sensors for urban stormwater monitoring: a review.

The large-scale deployment of low-cost monitoring systems has the potential to revolutionize the field of urban hydrology monitoring, bringing improved urban management, and a better living environment. Even though low-cost sensors emerged a few decades ago, versatile and cheap electronics like Arduino could give stormwater researchers a new opportunity to build their own monitoring systems to support their work. To find out sensors which are ready for low-cost stormwater monitoring systems, for the first time, we review the performance assessments of low-cost sensors for monitoring air humidity, wind speed, solar radiation, rainfall, water level, water flow, soil moisture, water pH, conductivity, turbidity, nitrogen, and phosphorus in a unified metrological framework considering numerous parameters. In general, as these low-cost sensors are not initially designed for scientific monitoring, there is extra work to make them suitable for in situ monitoring, to calibrate them, to validate their performance, and to connect them with open-source hardware for data transmission. We, therefore, call for international cooperation to develop uniform low-cost sensor production, interface, performance, calibration and system design, installation, and data validation guides which will greatly regulate and facilitate the sharing of experience and knowledge.

[Relationship between mannose-binding protein gene polymorphisms and disease progression and HBV DNA in patients with chronic HBV infection].

OBJECTIVE: To determine the influences of Mannose binding protein (MBP) gene polymorphisms on HBV DNA loads and on the progression of liver disease in patients with chronic HBV infection. METHOD: The Codons on 54 MBP gene polymorphisms and HBV DNA loads in a cohort of 395 patients with chronic HBV infection, including 244 with chronic hepatitis B (CHB), 151 with liver cirrhosis (LC) and 88 normal controls were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and fluorescent quantitative PCR (FQ-PCR). RESULT: The MBP genotype frequencies of GGC/GAC and alleles genetic frequencies of GAC in CHB group showed no significant differences comparing to the normal control group (P > 0.05). The MBP genotype frequencies of GGC/GAC and alleles genetic frequencies of GAC on CHB group (severe), compensation phase of LC group and decompensation phase of LC group were higher than those in the normal control group (P < 0.05), the genetic polymorphism of decompensation of LC was 36.5%, highest of all. The MBP genotype frequencies of GGC/GAC and alleles genetic frequencies of GAC of patients with chronic HBV infection were not changed with the differences of HBV-DNA loads. CONCLUSION: The codes on 54 MBP gene polymorphisms is not closely related to HBV DNA loads, but was associated with the progression of hepatitis B infection.

[Relationship between genetic polymorphisms of N-acetyltransferase and susceptibility to hepatocellular carcinoma].

OBJECTIVE: To study the possible relationship between genetic polymorphism of N-acetyltransferase 2 (NAT2) and susceptibility to hepatocellular carcinoma. METHODS: Genetic polymorphisms of the four NAT2 genes in 78 patients with hepatocellular carcinoma and 112 healthy controls were analyzed by means of real-time fluorescence light-Cycler. The difference in frequencies between the hepatocellular carcinoma patients and the controls were compared. RESULTS: The significant difference in slow acetylation genotype frequency was found between the controls and the hepatocellular carcinoma patients who were smokers (17.9% vs 37.5%, x(2)= 4.67, P<0.05) resulting in increased by 2.76 times the risk for hepatocellular carcinoma, but no evident difference between the controls and hepatocellular carcinoma patients who were non-smokers. CONCLUSION: The smokers with slow acetylation genotype of N-acetyltransferase 2 may be the population with high risk for hepatocellular carcinoma.