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Objectives: To evaluate the role and therapeutic value of homocysteine (hcy)-inducible endoplasmic reticulum stress (ERS) protein with ubiquitin like domain 1 (Herpud1) in hcy-induced calcific aortic valve disease (CAVD). Background: The morbidity and mortality rates of calcific aortic valve disease (CAVD) remain high while treatment options are limited.Methods: In vivo , we use the low-density lipoprotein receptor (LDLR) and Herpud1 double knockout (LDLR-/-/Herpud1-/-) mice assessment of aortic valve calcification lesions, ERS activation, autophagy, and osteogenic differentiation of aortic valve interstitial cells (AVICs). We used siRNA to knock down Herpud1 in cultured Primary AVICs were isolated from mice to further validate our findings. Results: Herpud1 was highly expressed in calcified human and mouse aortic valves as well as primary aortic valve interstitial cells (AVICs). Herpud1 deficiency inhibited hcy-induced CAVD in vitro and in vivo. Herpud1 silencing activated cell autophagy, which subsequently inhibited hcy-induced osteogenic differentiation of AVICs. Hcy increased Herpud1 expression through the ERS pathway and promoted CAVD progression. ERS inhibitor 4-phenyl butyric acid (4-PBA) significantly attenuated aortic valve calcification in high methionine diet–fed low-density lipoprotein receptor-/- (LDLR-/-) mice by suppressing ERS and subsequent Herpud1 biosynthesis. Conclusions: These findings identify a previously unknown mechanism of Herpud1 upregulation in CAVD progression, suggesting that Herpud1 silencing or inhibition is a viable therapeutic strategy for arresting CAVD progression.

Global warming concerns have pushed coal-fired power plants to develop innovative solutions which reduce CO2 emissions by increasing efficiency. While new ultra-supercritical units are built with extremely high efficiency, with Pingshan II approaching 50% LHV[1], subcritical units with much lower efficiency are a major source of installed capacity. The typical annual average net efficiency of subcritical units in China is about 37% LHV, and some are lower than 35% LHV. Since the total subcritical capacity in China is about 350GW and accounts for over one third of its total coal-fired power capacity, shutting all subcritical units down is not practical. Finding existing coal-fired plants a cost-effective solution which successfully combines advanced flexibility with high efficiency and low emissions, all while extending service lives, has challenged energy engineers worldwide. However, the (now proven) benefits a high temperature upgrade offers, compared to new construction options, made this an achievement worth pursuing. After many years of substantial incremental improvements to best-in-class technology, this first-of-its-kind subcritical high temperature retrofit successfully proves that a technically and economically feasible solution exists. It increases the main and reheat steam temperatures from 538°C (1000°F) to 600°C (1112°F), and the plant cycle and turbine internal efficiencies are greatly improved. This upgrade’s greatest efficiency gains occur at low loads, which is important as fossil plants respond to renewable energy’s increased grid contributions. These are combined with best-in-class flexibility, energy-savings, and technological advances, i.e., flue gas heat recovery technology and generalized regeneration technologies [4]. This project, the world’s first high-temperature subcritical coal-fired power plant retrofit, was initiated in April 2017 and finished in August 2019. Performance reports created by Siemens and GE record unit net efficiency at rated conditions improved from 38.6% to 43.5% LHV. The boiler’s lowest stable combustion load with operational SCR, without oil-firing support, was reduced from 55% to 19%. Substitution or upgrading of high-temperature components extended the lifetime of the unit by more than 30 years. At a third of the cost of new construction, this project set a high-water-mark for retrofitting subcritical units, and meets or supports the requisite attributes for Coal FIRST, Coal Plant of the Future, proposed by the United States Department of Energy (DOE) in 2019 [2].

A 72-h fine-resolution atmosphere-wave-ocean coupled forecasting system was developed for the South China Sea and its adjacent seas. The forecasting model domain covers from from 15°S to 45°N in latitude and 99°E to 135°E in longitude including the Bohai Sea, the Yellow Sea, the East China Sea, the South China Sea and the Indonesian seas. To get precise initial conditions for the coupled forecasting model, the forecasting system conducts a 24-h hindcast simulation with data assimilation before forecasting. The Ensemble Adjustment Kalman Filter (EAKF) data assimilation method was adopted for the wave model MASNUM with assimilating Jason-2 significant wave height (SWH) data. The EAKF data assimilation method was also introduced to the ROMS model with assimilating sea surface temperature (SST), mean absolute dynamic topography (MADT) and Argo profiles data. To improve simulation of the structure of temperature and salinity, the vertical mixing scheme of the ocean model was improved by considering the surface wave induced vertical mixing and internal wave induced vertical mixing. The wave and current models were integrated from January 2014 to October 2015 driven by the ECMWF reanalysis 6 hourly mean dataset with data assimilation. Then the coupled atmosphere-wave-ocean forecasting system was carried out 14 months operational running since November 2015. The forecasting outputs include atmospheric forecast products, wave forecast products and ocean forecast products. A series of observation data are used to evaluate the coupled forecasting results, including the wind, SHW, ocean temperature and velocity. The forecasting results are in good agreement with observation data. The prediction practice for more than one year indicates that the coupled forecasting system performs stably and predict relatively accurate, which can support the shipping safety, the fisheries and the oil exploitation.

The bottlenecks in developing high-efficiency ultra-super critical (USC) coal power technology are analyzed within the context of the growing pressure on the coal power industry to reduce carbon dioxide (CO2) emissions. To meet these demands, further improving the annual average operating efficiency of coal power is essential. A cross-compound double reheat unit design characterized by an elevated and conventional turbine layout is proposed in this paper. This new design can greatly shorten the length of expensive high-temperature piping required, significantly cut piping costs as well as reducing pressure drops and heat losses, resulting in a much higher efficiency and performance-price ratio than conventional double reheat design. The engineering study demonstrates the feasibility and advantages of this design. Now this new design is being implemented on Pingshan Phase II Project as a demonstration coal power unit in China. Despite the new turbine arrangement, Pingshan Phase II Project also adopts a series of energy saving, environmental protection, efficiency preservation and safety technologies, of which some have already gained success in Shanghai Waigaoqiao No. 3 Power Plant. Based on the new design and further optimization, the unit net efficiency of Pingshan Phase II is expected to achieve 49.8% under rated conditions on a lower heating value (LHV) basis. Combined with a series of innovative technologies that can keep the efficiency from decreasing under operational conditions, the annual average net efficiency can achieve 48.8% on LHV basis. This efficiency level is high enough to meet the strict CO2 emission standard proposed by United States Environment Protection Agency (U.S. EPA) based on the Pittsburgh #8 bituminous coal, showing significant potential for reducing CO2 emissions. A series of low-energy-consumption and even energy-saving pollutants removal technologies are also be applied on this project to harmonize high efficiency and low emissions.

After the retrofit of condensing power unit for heat supply, the reheat pressure of the unit deviates from the optimal value. When the heat supply and flow path of the turbine are retrofitted synchronously, or the retrofit of flow path is carried on the units witch heat supply retrofit had been done, the reheat pressure should be redetermined during the design phase of the flow path retrofit and the thermal economy of off-rated load should be taken into account to ensure the best operation efficiency of the unit. Taking 660MW supercritical single reheat unit as an example, the reheat pressure optimization analysis was carried out for the heat supply from the cold end piping of reheat system or the connection pipe between IP and LP in the wide load range. The results show that the optimization of the reheat pressure after the retrofit of heat supply can obtain significant gains of heat rate in the wide load range.

Under the pressure of reducing CO2 and pollutants emissions, The Chinese Government requires that all the existing coal-fired power units shall achieve an average net efficiency higher than 39.6% (LHV) by 2020. Considering the fact that the typical annual average net efficiency level of subcritical units is about 37%, some are even lower than 35%, it seems to be overambitious to achieve this target. The high temperature retrofit of subcritical units, however, find a technically and economically feasible solution for this problem, mainly on 4 aspects: 1) By improving the main and reheat steam temperatures from 538 °C to 600 °C, both the cycle efficiency and turbine internal efficiency are greatly improved. 2) By keeping the main and reheat steam pressures unchanged, combined with innovative boiler heating surfaces retrofit, the pressure parts of the boiler and feedwater system are utilized as much as possible thus the 600 °C steam temperatures are achieved with reasonable cost. 3) Combined with other energy-saving technologies, like flue gas heat recovery technology and generalized regeneration technologies, the unit efficiency is further improved under rated load, and even larger under part load. 4) By applying special startup technology and other efficiency preservation technologies, the solid particle erosion problem is suppressed thus the unit can operate efficiently in long term. Now the high temperature retrofit is being conducted in a typical 320 MW subcritical unit in Xuzhou, China. The target net efficiency under rated condition is higher than 42.36%, much better than those of all existing supercritical units and even some ultra-supercritical units. This project is expected to be a demonstration, setting a benchmark for the high efficiency retrofit of subcritical units.

The bottlenecks which in developing high-efficiency Ultra Super Critical (USC) coal power technology is analyzed under the background of great pressure of reducing CO2 emission on coal power industry. The development of 700°C Advanced Ultra Super Critical (A-USC) technology has been much slower than expected mainly due to the material limitations. Double reheat systems increase the efficiency at the cost of significant increases in expense and complexity. A cross compound unit with an elevated and conventional turbine layout greatly shorten the expensive high-temperature piping, significantly cutting the piping costs as well as reduce pressure drops and heat losses which increase the efficiency and the performance-price ratio of the power unit. Engineering study demonstrates the feasibility and advantages of this design. Existing 600 °C materials and equipment manufacturing capabilities were applied to the double reheat unit with the elevated and conventional turbine-generator layout, and adding other mature energy-saving technologies which had succeed in Shanghai Waigaoqiao No.3 Power plant to achieve a net efficiency of 49.8% (6849Btu/kWh, Lower Heating Value (LHV)). Combined with a series of innovative technologies that can improve the operating efficiency and keep the efficiency from decreasing, the annual net efficiency can achieve 48.8% (LHV). This efficiency level is high enough to meet the strict CO2 emission standard (636g/kWh) issued by Environmental Protection Agency (EPA) of the USA, showing significant demonstration of reducing CO2 emission.

The genus Streptococcus is one of the most genomically diverse and important human and agricultural pathogens. The acquisition of genomic islands (GIs) plays a central role in adaptation to new hosts in the genus pathogens. The research presented here employs a comparative genomics approach to define a novel family of GIs in the genus Streptococcus which also appears across strains of the same species. Specifically, we identified 9 Streptococcus genomes out of 67 sequenced genomes analyzed, and we termed these as 15bp Streptococcus genomic islands, or 15SGIs, including i) insertion adjacent to the 3′ end of ribosome l7/l12 gene, ii) large inserts of horizontally acquired DNA, and iii) the presence of mobility genes (integrase) and replication initiators. We have identified a novel family of 15SGIs and seems to be important in species differentiation and adaptation to new hosts. It plays an important role during strain evolution in the genus Streptococcus.

This engineering study demonstrates the feasibility and advantages of a cross compound unit with an elevated and conventional turbine layout. Existing materials and equipment manufacturing capabilities were used to design a double reheat unit using the elevated and conventional turbine layout with other mature energy-saving systems to achieve a net efficiency of 48.92%. The development of conventional coal-fired power plants is reviewed to describe the existing bottlenecks in high-efficiency Super Critical (SC) and Ultra Super Critical (USC) electrical generation units. The development of 700 °C Advanced Ultra Super Critical (A-USC) units has been much slower than expected mainly due to the material limitations. Double reheat systems increase efficiency but also significantly increase cost and complexity. This design reduces the use of expensive high-temperature materials, with significantly lower piping costs as well as lower pressure drops and heat losses which increase the efficiency and the performance-price ratio.

Continuous pressure of global warming and environmental pollutions pushes coal-fired power plants to develop in a more efficient and cleaner way. At present, the particular demands of Chinese grid for coal-fired power fleet, especially large peak-valley gaps, frequent start-ups, and shutdowns and cost pressures, bring the units especially the boilers more and tougher challenges, which result in the decline in combustion efficiency, frequent furnace explosions, the aggravation and collapse of slagging, and the burning of facilities in the downstream flue gas system of the boiler. In this paper, the innovative “generalized regeneration theory” and some typical techniques based on this theory are put forward and developed to provide new approach in more efficient, cleaner, and safer operation ways for coal-fired boilers. The packaged techniques, which include the new boiler start-up technique, the high-efficiency combustion and low emission technique under low load and the low oxygen, low NO x and high-efficiency combustion technique under high load, have been conducted successfully in the Shanghai Waigaoqiao No. 3 power plant. By improving the utilization of turbine extractions and reducing the exhaust loss, these innovative techniques greatly improve the efficiency, safety, environmental protection effect, and coal (especially high slagging tendency and moisture coal) adaptability of boilers in various operation conditions.

The 2×1000 MW ultra-supercritical steam turbine of Shanghai Waigaoqiao Phase III project, which uses grid frequency regulation and overload control through an overload valve, is manufactured by Shanghai Turbine Company using Siemens technology. Through optimization, the steam pressure is regarded as the criterion between constant pressure and sliding pressure operation. At high circulating water temperature, the turbine overload valve is kept closed when the unit load is lower than 1000 MW while at other circulating water temperatures the turbine can run in sliding pressure operation when the unit load is higher than 1000 MW and the pressure is lower than 27 MPa This increases the unit operation efficiency. The 3D bending technology in the critical piping helps to reduce the project investment and minimize the reheat system pressure drop which improves the unit operation efficiency and safety. By choosing lower circulating water design temperature and by setting the individual Boiler Feedwater Turbine condenser to reduce the exhaust steam flow and the heat load to the main condenser, the unit average back pressure and the terminal temperature difference are minimized. Therefore, the unit heat efficiency is increased.

In order to explore the interaction between the sea and monsoon in the South China Sea, the heat exchanges at air-sea interface during monsoon periods in 1986 were calculated using observational data. It shows that when the summer monsoon bursts and prevails over the South China Sea, the air-sea interface heat exchange is strong and the latent heat rises rapidly in the intertropical convergence zone and the tropic cyclone system near 20.49°N, 114.14°E. On May 24, 1986, the sensible heat became positive in the typhoon system. The heating exchange indicates that heat is transported from ocean to atmosphere, with major contribution of latent heat. When the summer monsoon prevails over the South China Sea and the weather is fine, even SST (sea surface temperature) is high, but sensible heat appears to be negative. The heat exchange indicates that heat is transported from atmosphere to ocean, with major contribution of short-wave radiation absorbed by sea surface and sensible heat. When summer monsoon is over and the northeast monsoon prevails over the South China Sea, the heat exchange at air-sea interface is very strong. The heating exchange shows that the ocean heats the atmosphere, with major contribution of latent heat when cold air arrives at the sea surface and the sensible heat rises to positive rapidly. Therefore it can be concluded that the heat exchange at air-sea interface is different from the SST in South China Sea. When the summer monsoon prevails over the South China Sea, the main trend is the ocean responding to the atmosphere.

Scintillation and beam drifting are the two main issues, which influence the performance of optical wireless communication system. Multiple propagation paths average effect could be used to alleviate scintillation to these considerations, a 155-622 Mb/s optical wireless communication system was dilation, auto tracking can be used to compensate the beam drifting caused by mirage-like effect. Developed using multiple 800nm laser diode transmitters and auto tracking. Block diagram of design and main elements of the key optics, mechanics, and server control system are presented, and link performances of 155Mb/sand 622 Mb/s digital data transmission by using 3 transmitters over 1 .3 km are illustrated in this paper.