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Raphidiopsis raciborskii, which harms water supply and ecological security, may expand its range with climate warming. To explore the ecological management method of R. raciborskii blooms, the co-culture system of Eichhornia crassipes and R. raciborskii was established to study the inhibitory effect and inhibition mechanism of E. crassipes on R. raciborskii compared with the shaded culture of R. raciborskii alone. It was found that after co-cultured with E. crassipes (fresh weight, 5.10 ± 0.60 g·L−1) for seven days under initial high nutrient concentration, the algal cell density of co-culture groups with an initial cell density of 1.57 × 108 cells·L−1 and 1.57 × 109 cells·L−1 decreased by 63.19% and 14.87%, respectively. Meanwhile, the algal cell density in the co-culture group was significantly lower than that in the control group (p < 0.01). The algal cell density change showed that the growth of R. raciborskii was inhibited by co-cultured E. crassipes. In addition, E. crassipes could significantly reduce the nitrogen and phosphorus content in the water, but the growth state and photosynthesis of E. crassipes were not inhibited by R. raciborskii. These results suggested that E. crassipes has the potential to control R. raciborskii blooms. The study also found that when co-cultured, there was no significant difference in algal cell density between the groups supplemented with a certain amount of nutrients and the group without additional nutrients. Meanwhile, the inhibition rates of the co-culture groups were over 99% on day 4. These results showed that nutrient factors had no significant effect on the inhibitory effect of E. crassipes in the range of nutrients regulated by the experiment, and other factors played a leading role. In other words, under experimental conditions, nutrient competition was not the primary inhibitory mechanism of E. crassipes. This study also confirmed that E. crassipes had inhibitory allelopathy on R. raciborskii. The contribution and significance of allelopathy and other mechanisms could be studied in the future.

To assess the clinical and imaging features of IgG4-RKD for understanding and diagnosis of this disease. CT and MR images of 34 patients with IgG4-RKD were retrospectively analyzed by two radiologists in consensus. The serum IgG4 level was found being increased in all patients. Renal involvement was bilateral (24/34, 70.6%) or unilateral (10/34,29.4%), multiple (29/34, 85.3%) or solitary (5/34, 14.7%). The lesions were wedge-shaped (21) or mass-like (4) in the renal parenchyma, whereas diffusely decreased renal density was noted in 2 patients. All lesions showed progressive contrast enhancement. The 4 mass-like lesions were misdiagnosed as renal malignancy. In 15 patients with follow-up imaging examinations, the number and size of renal lesions decreased after oral hormone treatment. The serum IgG4 levels were significantly decreased after therapy in all patients. IgG4-RKD has various imaging appearances. Although the mass-like appearance mimics renal malignancy in some patients, progressive contrast enhancement in the lesion with elevated serum IgG4 suggests IgG4-RKD.

Valorization of captured CO2 is an important but challenging topic since CO2 is a stable and relatively inert compound. Nonetheless, CO2 valorization technologies should be sought after, because th...

White Rabbit (WR) technology combines gigabit Ethernet data transfer with synchronization at subnanosecond accuracy and picoseconds precision over the same fiber medium. In some applications, the WR link must maintain the synchronization accuracy over a wide temperature range. The temperature effect on a WR link is measured, and contributions from different components like optical fiber, optical transceiver, and fixed delay onboard are separately studied and analyzed. An online real-time temperature correction method is introduced to reduce the influence on synchronization accuracy of the onboard temperature variation.

This paper presents an automatic temperature correction design for carry chain based time-to-digital converter (TDC) in field-programmable gate array (FPGA). The bin-by-bin calibrations under different temperatures are performed for both plain TDC and Wave Union TDC to characterize the influence of temperature variation on the delay time of carry chain. Accordingly, a simplified temperature correction scheme by using a dedicated correction channel to measure the coefficient and correct fine time result for all TDC channels is implemented and tested. This method shows only few picosecond errors for both simulation and measurement. With this correction approach, a TDC precision of 21 ps has been achieved in Cyclone II FPGA under a wide ambient temperature range from 0 $^\circ{\rm C}$ to 60 $^\circ{\rm C}$ . Several design key points are also described in this paper.

As a component of architectures, stone reliefs prevailing during the Han Dynasty (206BC–AD220) were usually found in coffin chambers and ancestral temples. Although the stone reliefs represent stone carving techniques of the Han Dynasty (202BC–AD220), little information about these techniques were known. In this study, the digital microscope with 3D surface reconstruction based on extended depth of focus (EDF) technology was used to investigate tool marks of stone reliefs excavated at the Mausoleum of Cao Cao (AD155–AD220) at the end of the Eastern Han Dynasty (AD25–AD220). The tool marks analysis shows that different carving techniques were involved. The surface was ground by a rotary grinding tool. Small flat-head tool could be used to lower the background. Curved lines were engraved by an oblique attack technique and the burin was held at the angle of about 35° to the contact surface. Thin straight lines were engraved by an upright attack technique. Concentric circles were possibly engraved by the dragging action of a tool like a h-shaped compass. Furthermore, it is envisioned that the EDF technology provide a new effective approach for tool marks analysis.

The Large High Altitude Air Shower Observatory (LHAASO) project consists of a complex detector array with over 6000 detector nodes spreading over 1.2 km2 areas. The arrival times of shower particles are captured by time-to-digital converters (TDCs) in the detectors' frontend electronics, the arrival direction of the high energy cosmic ray are then to be reconstructed from the space-time information of all detector nodes. To guarantee the angular resolution of 0.5°, a time synchronization of 500 ps (RMS) accuracy and 100 ps precision must be achieved among all TDC nodes. A technology enhancing Gigabit Ethernet, called the White Rabbit (WR), has shown the capability of delivering sub-nanosecond accuracy and picoseconds precision of synchronization over the standard data packet transfer. In this paper we demonstrate a distributed TDC prototype system combining the FPGA based TDC and the WR technology. With the time synchronization and data transfer services from a compact WR node, separate FPGA-TDC nodes can be combined to provide uniform time measurement information for correlated events. The design detail and test performance will be described in the paper.

Aiming to high sensitivity and wide spectrum of cosmic ray detection, the Large High Altitude Air Shower Observatory (LHAASO) project consists of over 10,000 detectors of different types, spreading over 1.2 km2. To precisely reconstruct the air shower events with high angular resolution, all detector electronics and digitizers should work in synchronous acquisition mode with a global timing error less than 5 ns (rms). This large scale and high precision timing requirement exceeds the capability or feasibility of traditional methods such as GPS and echo-delay calibration. Recently an emerging method named White Rabbit (WR) was proposed and demonstrated as a cost-effective solution that combines Gigabit Ethernet data transfer and subnanosecond precision timing transfer over the same fiber media. Furthermore, the White Rabbit network also enables direct digitization and trigger-less data acquisition mode for each detector, which will greatly reduce the complexity and improve the performance of the data acquisition (DAQ) system. In this paper we will demonstrate the design and development status of a WR timing and DAQ network in the LHAASO project.

The Large High Altitude Air Shower Observatory (LHAASO) project aims to search the origin of galactic cosmic rays above 30TeV with high sensitivity and wide spectrum, it's a dedicated instrument made by 4 sub-detector arrays. The square kilometer complex array (KM2A) consists 5635 scintillation electron and 1221 muon detectors covering the area of 1.2Km2. To guarantee the angular resolution of reconstructed air shower event, a 500ps (rms) timing synchronization must be achieved among the spread few thousand detectors.

ZYNQ is the new all programmable SoC architecture of FPGA with dual-core high performance ARM Cortex-A9 processors from Xilinx. A new module with Giga-bit Ethernet interface based on the ZYNQ XC7Z010 is development for the High Purity Germanium Detectors' data acquisition in the CJPL (China JingPing under-ground Lab) experiment. With the new architecture of ZYNQ, the embedded open source Linux with TCP/IP stack and the real time high throughput logic based on VHDL can be combined to run in a single ARM + FPGA chip with lower profile, lower power and highest performance. It's very differently from the classic architecture with two chips, one processor plus one FPGA. This paper will introduce how about the architecture of the readout module and how the new module can archive higher performance than the classic one. Also the throughput of the Giga-bit Ethernet which more than 500Mbps will be introduce and a verify platform of HPGe data acquisition system based on the new module will also be introduced.

This paper presents a temperature compensation design for carry chain based Time-to-Digital Converter (TDC) in FPGA. The bin-by-bin calibrations under different temperatures are performed for both plain TDC and Wave Union TDC to characterize the influence of temperature variation on the delay time of carry chain which shows all TDC channels have the similar temperature-LUT coefficient. Accordingly, a simplified temperature compensation scheme by using a dedicated correction channel to measure the coefficient and correct fine time result for all TDC channels is implemented and tested. This method shows only few picosecond errors for both simulation and measurement. With this compensation approach, a 21ps RMS TDC resolution has been achieved in Cyclone II FPGA under a wide temperature range from 10°C to 75°C. Several design key points are also described in this paper.

The subnanosecond time resolution readout system includes a time discriminator module and a TDC module is designed for reading the signals detected by the MCP from the X-ray pulsar. The periodicity of the signals from the specific pulsar will be detected under a high background level with this system. Through the delay chain designed in the FPGA, the time accuracy of this TDC module is able to reach less than 500ps. To keep in line with the time resolution of the TDC, the jitter of the time discriminator module need to be designed less than 500ps. Through a special design with the chips ADCMP580 and NB7V52M, the time resolution required by pulsar-based navigation could be finally achieved by this readout system.

Emissions of volatile organic compounds (VOCs) were studied from three heavily polluted rivers (Huijiang, Nancun, and Zengbian Rivers) in Guangzhou, South China. A total of 49 species of VOCs were identified. Nancun River had the highest concentration of total VOCs (TVOCs), which ranged from 1,467 to 5,522 μg m−3. Trichloroethene, benzene, toluene, ethylbenzene, m/p-xylene, o-xylene, styrene, and 1,3,5-trimethylbenzene were the main pollutants. The levels of VOCs evaporated from the three rivers exhibited different patterns. Correlations between the concentrations of major VOCs were established and found to be statistically significant, except for o-xylene. The ratios of toluene/benzene, ethylbenzene/benzene, and xylene/benzene were estimated and found to be higher than widely reported in the literature. TVOC fluxes in the three rivers were calculated to be the range from 24.8 to 765 μg m−2 h−1. This study provides a regional background for the emission inventories of VOCs from heavily polluted rivers in southern China and provides resource managers with important information to guide remediation and policy concerning VOC emissions to the environment.

Sub-nanosecond precision timing distribution and control are key techniques in various distributed real-time applications, where the proposed White Rabbit (WR) project provides a solution combining both data transmission and timing control via the same media. This paper demonstrates the design and development of a compact, standalone WR node following FPGA Mezzanine Card (FMC) standard, which would work as a common WR interface to different applications. Test results show that the timestamp synchronization precision of 65ps (RMS) has been observed between the node and a WR switch, and the data throughput of over 0.3Gbps has been verified in a preliminary test between the node and a PC host.