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Based on comparative analysis on hydrochemical characteristics of geothermal water in the north part of Liaokao fault, this research focuses on studying the indicative significance of hydrochemical characteristics for the formation of geothermal water. The result shows that: (1) There is no obvious hydraulic connection between the karst geothermal water (occurred in the east part of the Liaokao fault) and the sandstone geothermal water (occurred in the west part of Liaokao fault). (2) In a close hydrological environment, caused by tectonic activities, geothermal water remains longer time in reservoir, hence the water-rock interaction is more complete, with high degree of concentrations, whereas the renewable capacity of the water is weaker. (3) There is no high temperature mantle source fluid mixed in the geothermal water. Karst geothermal water occurred deep circulatory convection along Liaokao fault and its secondary fault, therefore there is deep crust source fluid added into the geothermal water, closer to the Liaokao fault, the greater affected by the deep crust fluid. However, sandstone geothermal water has weak deep circulatory convection.

Background With the wide use of antibiotics, antibiotic-resistant Helicobacter pylori strains are becoming increasingly prevalent. It has been hypothesized that culture-guided therapy might help to increase treatment success. But the effects and the costs still remain controversial. Aims To systematically review the efficacy and the cost of culture-guided triple therapy, compared to standard triple regimen for first-line treatment of Helicobacter pylori infection. Methods A search of the Cochrane Library, PubMed, EMBASE, Science Citation Index Expanded and CBM was performed. Randomized controlled trials comparing culture-guided triple therapy to standard triple therapy in the first-line treatment of Helicobacter pylori infection were selected for meta-analysis. Relative risk was used as a measure of the effect of two regimens mentioned above with a fixed-effects model using the methods of DerSimonian and Laird. Results Five randomized controlled trials totaling 701 patients were included. The meta-analysis showed that culture-guided triple therapy was superior referring to a higher eradication rate from intention-to-treat analyses (RR, 0.84; 95% CI,0.77, 0.90; p

Background Moxifloxacin-based triple therapy has been suggested as an alternative first line therapy to clarithromycin-based triple therapy for Helicobacter pylori infection. Aims To systematically review the efficacy and tolerance of moxifloxacin-based triple therapy, and to conduct a meta-analysis of studies comparing this regimen with clarithromycin-based triple therapy. Methods A search of The Cochrane Library, PUBMED, EMBASE, EBM Review databases, Science Citation Index Expanded, and CMB (Chinese Biomedical Literature Database) was performed. Randomized controlled trials comparing moxifloxacin-based triple therapy to gold standard triple therapy in the first-line treatment of Helicobacter pylori infection were selected for meta-analysis. Relative risk was used as a measure of the effect of the two above-mentioned regimens with a fixed-effects model using the methods of DerSimonian and Laird. Results Four randomized controlled trials totaling 772 patients were included. The meta-analysis showed that the mean eradication rate was 84.1 (318/378) in the moxifloxacin-based triple therapy group and 73.6 (290/394) in the clarithromycin-based triple therapy group; there was statistical significance between the two groups (RR, 1.13; 95% CI, 1.01, 1.27; P=0.04). There were no statistically significant difference in the overall side effects (RR, 0.61; 95% CI, 0.25, 1.48; P

Hardness is among the most important attributes of an object that humans learn about through touch. However, approaches for robots to estimate hardness are limited, due to the lack of information provided by current tactile sensors. In this work, we address these limitations by introducing a novel method for hardness estimation, based on the GelSight tactile sensor, and the method does not require accurate control of contact conditions or the shape of objects. A GelSight has a soft contact interface, and provides high resolution tactile images of contact geometry, as well as contact force and slip conditions. In this paper, we try to use the sensor to measure hardness of objects with multiple shapes, under a loosely controlled contact condition. The contact is made manually or by a robot hand, while the force and trajectory are unknown and uneven. We analyze the data using a deep constitutional (and recurrent) neural network. Experiments show that the neural net model can estimate the hardness of objects with different shapes and hardness ranging from 8 to 87 in Shore 00 scale.

Hardness sensing is a valuable capability for a robot touch sensor. We describe a novel method of hardness sensing that does not require accurate control of contact conditions. A GelSight sensor is a tactile sensor that provides high resolution tactile images, which enables a robot to infer object properties such as geometry and fine texture, as well as contact force and slip conditions. The sensor is pressed on silicone samples by a human or a robot and we measure the sample hardness only with data from the sensor, without a separate force sensor and without precise knowledge of the contact trajectory. We describe the features that show object hardness. For hemispherical objects, we develop a model to measure the sample hardness, and the estimation error is about 4% in the range of 8 Shore 00 to 45 Shore A. With this technology, a robot is able to more easily infer the hardness of the touched objects, thereby improving its object recognition as well as manipulation strategy.

Robust manipulation and insertion of small parts can be challenging because of the small tolerances typically involved. The key to robust control of these kinds of manipulation interactions is accurate tracking and control of the parts involved. Typically, this is accomplished using visual servoing or force-based control. However, these approaches have drawbacks. Instead, we propose a new approach that uses tactile sensing to accurately localize the pose of a part grasped in the robot hand. Using a feature-based matching technique in conjunction with a newly developed tactile sensing technology known as GelSight that has much higher resolution than competing methods, we synthesize high-resolution height maps of object surfaces. As a result of these high-resolution tactile maps, we are able to localize small parts held in a robot hand very accurately. We quantify localization accuracy in benchtop experiments and experimentally demonstrate the practicality of the approach in the context of a small parts insertion problem., National Science Foundation (U.S.) (NSF Grant No. 1017862), United States. National Aeronautics and Space Administration (NASA under Grant No. NNX13AQ85G), United States. Office of Naval Research (ONR Grant No. N000141410047)