Research on neural network prediction method for upgrading scale of natural gas reserves

With the gradual decline of natural gas production, reserve upgrading has become one of the important issues in natural gas exploration and development. However, the traditional reserve upgrade forecasting method is often based on experience and rules, which is subjective and unreliable. Therefore, a prediction method based on neural network is proposed in this paper to improve the accuracy and reliability of reserve upgrade prediction. In order to achieve this goal, by collecting the relevant data of natural gas exploration and development in Sichuan Basin, including geological parameters, production parameters and other indicators, and processing and analyzing the data, the relevant characteristics of reserves increase are extracted. Then, a neural network model based on multi-layer perceptron (MLP) is constructed and trained and optimized using backpropagation algorithm. The results show that the prediction accuracy of the constructed neural network model can reach more than 90% and can effectively predict the reserve upgrading. Experiments show that the model has high accuracy and reliability, and is significantly better than the traditional prediction methods. The method has good stability and reliability, and is suitable for a wider range of natural gas fields

Rapamycin Nano-Micelle Ophthalmic Solution Reduces Corneal Allograft Rejection by Potentiating Myeloid-Derived Suppressor Cells' Function

Allograft rejection is the major cause of corneal allograft failure. Rapamycin (RAPA) has been reported as an effective and novel immunosuppressive agent for patients undergoing corneal transplantation. However, its high water insolubility and low bioavailability have strongly constrained its clinical application. In this study, we successfully developed a RAPA nano-micelle ophthalmic solution and found that corneal allograft survival in recipients treated with RAPA nano-micelle ophthalmic solution was significantly prolonged for more than 2 months, with less inflammatory infiltration, decreased production of pro-inflammatory factors, and elevated recruitment of myeloid-derived suppressor cells (MDSCs). MDSCs from mice treated with RAPA nano-micelle ophthalmic solution could significantly inhibit the proliferation of CD4+T cells through increased expressions of inducible nitric oxidase (iNOS) and arginase-1 (Arg-1). The activity blockade of Arg-1 and iNOS pharmacologically reversed their immunosuppressive ability. Moreover, the effects of RAPA were antagonized by the administration of anti-Gr-1 antibody or by inhibiting the activity of iNOS pharmacologically. In addition, RAPA nano-micelle also effectively alleviated allograft rejection in high-risk rabbit penetrating keratoplasty (PKP) models with corneal vascularization. Collectively, our results demonstrate that RAPA nano-micelle ophthalmic solution could improve the immunosuppressive activity of MDSCs through elevated expression of Arg-1 and iNOS, which highlights the possible therapeutic applications of RAPA against corneal allograft rejection

Identification, Characterization and Application of a G-Quadruplex Structured DNA Aptamer against Cancer Biomarker Protein Anterior Gradient Homolog 2

Background: Anterior gradient homolog 2 (AGR2) is a functional protein with critical roles in a diverse range of biological systems, including vertebrate tissue development, inflammatory tissue injury responses, and cancer progression. Clinical studies have shown that the AGR2 protein is overexpressed in a wide range of human cancers, including carcinomas of the esophagus, pancreas, breast, prostate, and lung, making the protein as a potential cancer biomarker. However, the general biochemical functions of AGR2 in human cells remain undefined, and the signaling mechanisms that drive AGR2 to inhibit p53 are still not clearly illustrated. Therefore, it is of great interest to develop molecular probes specifically recognizing AGR2 for its detection and for the elucidation of AGR2-associated molecular mechanism. Methodology/Principal Findings: Through a bead-based and flow cytometry monitored SELEX technology, we have identified a group of DNA aptamers that can specifically bind to AGR2 with K-d values in the nanomolar range after 14 rounds of selections. Aptamer C14B was chosen to further study, due to its high binding affinity and specificity. The optimized and shortened C14B1 has special G-rich characteristics, and the G-rich region of this binding motif was further characterized to reveal an intramolecular parallel G-quadruplex by CD spectroscopy and UV spectroscopy. Our experiments confirmed that the stability of the G-quadruplex structure was strongly dependent on the nature of the monovalent ions and the formation of G-quadruplex structure was also important for the binding capacity of C14B1 to the target. Furthermore, we have designed a kind of allosteric molecule beacon (aMB) probe for selective and sensitive detection of AGR2. Conclusion/Significance: In this work, we have developed new aptamer probes for specific recognition of the AGR2. Structural study have identified that the binding motif of aptamer is an intramolecular parallel G-quadruplex structure and its structure and binding affinity are strongly dependent on the nature of the monovalent ion. Furthermore, with our design of AGR2-aMB, AGR2 could be sensitively and selectively detected. This aptamer probe has great potential to serve as a useful tool for early diagnosis and prognosis of cancer and for fundamental research to elucidate the biochemical functions of AGR2.National Basic Research Program of China [2010CB732402]; National Instrumentation Program [2011YQ03012412]; Natural Science Foundation of Fujian Province for Distinguished Young Scholars [2010 J06004]; National Found for Fostering Talents of Basic Science [J1030415

Development of Advanced Composting Technologies for Municipal Organic Waste Treatment in Small Communities in Newfoundland and Labrador

Municipal Solid Waste (MSW) is one of the major fractions of the solid waste in Canada. From 2002 to 2008, Canadian municipal solid waste disposal has increased from 769 kilograms to 777 kilograms per capita. Among the provinces, Newfoundland and Labrador (NL) has one of the highest waste disposal levels per capita in the country. According to the Multi Materials Stewardship Board (MMSB), it is estimated that more than 400,000 tonnes of municipal solid waste (MSW) materials are generated each year in this province and organic waste makes up as much as 30% of all waste generated. To properly manage MSW generated, the Provincial Solid Waste Management Strategy has been identified in 2002, aiming to reduce the amount of waste going into landfills by 50 per cent. Composting has been regarded as an efficient and effective way to deal with the organic waste and helps work toward achieving the provincial 50 per cent waste reduction goal. It also creates rich organic soil that can enhance lawns and gardens. Therefore, MSW composting has been listed as one of the six new environmental standards applied to new waste management systems in NL. However, NL comprises more than 200 small communities without access to the central composting facility. For those areas, small-scale composting technologies are desired to manage their MSW so as to reduce collection and transport costs and eliminate the other environmental contamination during transportation. Composting is a biological process that is affected by chemical and physical factors. The lack of understanding of the complexity of biological, chemical, and physical processes can result in malfunction of a composting system. The microbial and physicochemical environment in composting can be affected by the diversity of microbial population, temperature, bulking agent, aeration, and chemical properties of raw material such as the C/N ratio and moisture content. Interactions among biological, chemical, and physical factors are crucial to the comprehensive understanding of the composting process, and thus viable for process control and system optimization. This project aims at developing composting technologies applicable to northern communities in NL, and conducting system optimization to increase the composting efficiency and improve compost quality. Six composting reactors (50×20×25 cm) were designed and manufactured. Six mixers were installed in each reactor. An inlet was designed to provide air through a vacuum pump. A perforated plate with holes was installed for air distribution in the system. The exhaust gas was monitored by a gas monitoring system and then discharged into a flask containing H2SO4 solution (1 M) to absorb the NH3. To prevent heat loss, heat insulating layers were designed and applied to cover the reactor thoroughly. Reactors were filled with food waste as raw material. Factorial design was applied, with sixteen runs conducted, to optimize the operational factors including moisture content, aeration, bulking agent, and C/N ratio. Each composting run lasts 30 days. The effect of main factors and their interactions on composting process was investigated by measuring temporal variations of enzyme activities (dehydrogenase, β-glucosidase, and Phosphomonoesterase), germination index (GI), pH, electrical conductivity (EC), temperature, moisture, ash content, oxygen uptake rate (OUR), and C/N ratio during composting. Experimental results showed that the breakdown of organic matter by microbial activities led to increase in the temperature of the composting material. As composting progresses, the amount of degradable matter decreased and the temperature declined. When most of the organic matter was consumed, the temperature in the reactor dropped to the ambient temperature. The OUR can express biological activities during composting and biological stability at the end of composting. The OUR values showed strong correlation with temperature. The maximum OUR was observed concurrently with the maximum temperature. The pH value was low at the first stage due to the accumulation of organic acids, and increased gradually while organic acids were consumed by microorganisms. The EC values increased in all runs as a result of cation concentration increment. Moisture content showed descending trends in all runs due to the evaporation under high temperature. As a result of decomposition of organic matter by composting, the organic matter decreased and ash content increased in all runs. Although the GI data showed notable fluctuation during composting, it started to increase at the end of the composting process. In most of the runs, the peaks of dehydrogenase activity as an indicator of biological activity were observed with the maximum temperature and OUR value simultaneously. The β-glucosidase activity showed with high values at the themophilic phase and after the temperature drop. In addition, high activity of phosphomonoesterase accrued during the thermophilic phase. Results of the factorial design indicated that aeration rate, moisture content, and bulking agents affect the maximum temperature significantly. Aeration rate has significant influence on the maximum OUR. The C/N ratio and the interaction between aeration rate and bulking agent have major impact on GI. Moisture content is an important factor affecting the cumulative dehydrogenase and the β-glucosidase activity. The C/N ratio influences the β-glucosidase activity as well. The output of this research can help to design the small-scale composting system for MSW management in small communities in NL, and provide a solid base of technical and scientific knowledge for system operation

Performance of locally available bulking agents in Newfoundland and Labrador during bench-scale municipal solid waste composting

Background: Newfoundland and Labrador (NL) has one of the highest waste disposal rates in Canada and it has 200 small communities without access to central composting facilities. During Municipal solid waste (MSW) composting, the selection of bulking agents is critical. Bench-scale composting systems plus locally available bulking agents are thus desired for economic and effective MSW management in NL communities. This study evaluated the performance of locally available bulking agents (i.e., NL sawdust and peat) during MSW composting in a bench-scale system. Physiochemical (temperature, oxygen uptake rate, pH, electrical conductivity, moisture and ash content, and C/N ratio) and biological (enzyme activities and germination index) parameters were monitored to evaluate compost maturity and stability. Results: In peat composting, higher temperature for a longer duration was observed, indicating more effective pathogen removal and sterilization. High enzyme activities of dehydrogenase, β-glucosidase, and phosphodiesterase in the third week of composting imply high microbial activity and high decomposition rate. The low C/N ratio for compost product implies acceptable stability states. In sawdust composting, higher temperature and oxygen uptake rate (OUR) were observed in the third week of composting, and higher enzyme activities in the second week. Sawdust composting generated a higher germination index, indicating higher maturity. Conclusions: Both sawdust and peat are effective bulking agents for the bench-scale composting. The choice of a bulking agent for a particular community depends on the availability of the agent and land in the region, convenience of transportation, price, and the expected quality of the compost product

From Challenges to Opportunities: Towards Future Strategies and a Decision Support Framework for Oil Spill Preparedness and Response in Offshore Newfoundland and Labrador

As a major energy source worldwide, oil products are increasingly produced and consumed. Despite progress in reducing spillage through a variety of technological and regulatory measures, along with improving industry practices, oil spills continue to occur. On a daily basis, hundreds to thousands of spills are likely to occur worldwide in many different types of environments such as on land, at sea, and in inland freshwater systems. Multiple sources of spillage are involved, such as tankers, offshore platforms, drilling rigs and wells, as well as through a variety of processes of transportation, refining, storage and utilization of refined petroleum products and their by-products. Spills occur for diverse reasons including structural failures, operational errors, weather-related events, earthquakes, human negligence, and even vandalism or terrorism. The biggest contributor to oil pollution in the world’s oceans (some 45%) is operational discharges from tankers. Most oil spill occurrences (72%) are on a small scale and the overall amount of these small spills accounts for less than 1% of the total spillage. The largest spills (over 30 tonnes) rarely occur (0.1% of incidents) yet involve nearly 60% of the total amount spilled. The project’s objective was to gain insight to current methodologies and technologies in oil spill response and countermeasures and to formulate a new strategic and decision making framework for supporting oil spill diagnosis, warning and emergency response in a cost-efficient and environmental friendly manner. The cold weather and harsh offshore conditions in Newfoundland and Labrador and their effects will be considered in the study. The main objectives of the research included: • Collect and analyze background information and data of historical oil spills and associated environmental, economic and societal impacts as well as relevant policies and regulations • Review current offshore oil spill response and countermeasure protocols and practices • Review the natural and social conditions, spill prevention, monitoring and analysis, assessment and modeling, and response and clean-up technologies, as well as their effectiveness and suitability in harsh environments prevailing in NL offshore areas • Identify knowledge gaps and technical challenges in offshore oil spill, monitoring, analysis, modeling, responses, and countermeasures particularly in harsh environmental conditions • Formulate a general decision making framework for integrating methods and techniques during oil spill monitoring, early warning, assessment, simulation, response and cleanup processes • Recommend oil spill management strategies and disclose the research and development needs particularly for NL offshore industry and regulatory authorities. Based on the comprehensive review, this study made general recommendations to help guide research and development efforts in oil spill response and countermeasures from the aspects of impact assessment, regulations and coordination, monitoring and analysis, modeling and prediction, preparedness and response, countermeasures, and decision making. Some special recommendations given to future investment and R&D efforts in order to address the identified knowledge gaps and technical challenges associated with the NL’s harsh offshore environment include: • Uncertainties associated with the weather and ocean conditions and the impacts on spill modeling and response decision making; • Integration of monitoring, assessment, simulation and optimization into offshore oil spill response decision making; • Capability of existing technologies in harsh environments and novel technologies customized with the specific characteristic of NL offshore oil spills; and • Adaptation of long-term contingency plans, management strategies, on-site response decision, and operational technologies to harsh environmental conditions

The effects of using an active workstation on executive function in Chinese college students.

This study aimed to examine the effects of active workstation use on the executive function by measuring the three components of executive function (Inhibition, Updating, and Shifting) during sitting, standing, and walking at an active workstation with different speeds. Twenty-four college students completed a cognitive test battery while sitting, standing, walking on an active workstation with a self-selected speed (mean = 2.3 km/h) and a faster speed (mean = 3.5 km/h). The three components of executive function (Inhibition, Updating, and Shifting) were assessed by Stroop task, N-back task, More-odd shifting task, respectively. Performance of each task was determined by the response time and accuracy. Repeated measures ANOVAs were conducted with workstation condition and trial type as within-subjects factors. There were no significant main effects for workstation condition and no interaction between workstation condition × trial type in Stroop task and More-odd shifting task. There was a significant main effect for workstation condition (F (3, 69) = 4.029, p = 0.011) and interaction effect between workstation condition × trial type (F (6, 138) = 9.371, p < 0.001) in N-back task. Decomposition of the interaction showed that accuracy of 2-back task in self-paced walking was significantly lower than that in sitting condition (p = 0.017) and in standing condition (p < .001). But there was no difference in accuracy of 2-back task between self-paced walking condition and faster walking condition (p = 0.517). Our results suggest that using an active workstation may have a selective impact on three components of executive function, in which the Updating may be impaired to a certain extent while the Inhibition and Shifting remain unaffected

Additional file 1 of Prognostic role of the systemic immune-inflammation index in biliary tract cancers: a meta-analysis of 3,515 patients

Additional file 1. The PRISMA checklist