Plasma position measurements by O-mode and X-mode reflectometry systems in tokamak plasmas.

Plasma Position Reflectometry (PPR) is planned to provide plasma position and shape information for plasma operation in future fusion reactors. Its primary function is to calibrate the drift of the magnetic signals due to the integral nature of magnetic measurement. Here, we attempt to measure plasma position using ordinary mode (O-mode) and extraordinary mode (X-mode) reflectometry systems on two tokamaks. A new physical model based on the phase shift is proposed to deduce the relative movement of the cut-off layer without density inversion. We demonstrate the plasma position measurements by absolute measurement from density profile inversion and relative measurement from phase shift. The combination of X-mode and O-mode reflectometers can minimize the limitations of single polarization reflectometry and further increase the accuracy of plasma position measurement. These results could provide an important technical basis for the further development of a real-time control system based on PPR.

Preliminary results of the 105 GHz collective Thomson scattering system on HL-2A.

A 105 GHz collective Thomson scattering (CTS) diagnostic has been successfully developed for fast-ion measurements on the HL-2A tokamak, and it has been deployed during an experimental campaign. Enhanced signals exhibiting synchronous modulation characteristics have been observed across all CTS channels upon the launch of a modulated probe wave. Results show that the intensity of the CTS signal increases with Neutral Beam Injection (NBI) power and is proportional to neutron count, indicating that the scattering signal contains a contribution from fast ions. Compared with the signal without NBI, the enhanced scattering spectrum due to NBI is slightly wider than the predicted fast ion range. Such broadening might be attributed to the heating effects of the gyrotron.

[Progress of researches on schistosomiasis-associated pulmonary arterial hypertension].

Schistosomiasis-associated pulmonary arterial hypertension (Sch-PAH) is categorized as WHO Group I PAH because its clinical manifestations, laboratory and hemodynamic features share with PAH of other etiologies, such as idiopathic, heritable, HIV and autoimmune disorders. Sch-PAH is usually a life-threatening complication of hepatosplenic schistosomiasis characterized by changes in the vascular wall, remodeling and vasoconstriction with lesions primarily located in the precapillary segments of the pulmonary vasculature, which may result in a marked and sustained increase in pulmonary vascular resistance, right ventricular failure and ultimately death. Although egg deposition into lung and subsequent inflammatory cascades are key factors in the pathogenesis of Sch-PAH, the exact pathogenesis, course of disease and treatment of Sch-PAH remain largely uncertain. This review mainly discusses the pathophysiological and immunological mechanisms of Sch-PAH, so as to provide insights into the clinical diagnosis and treatment of Sch-PAH.

Development of solid state terahertz interferometer for the first plasma on HL-2M tokamak.

A solid state terahertz interferometer has been developed on the recent commissioned HL-2M tokamak. It can work in a wide frequency region of 220-325 GHz, and the terahertz wave is generated from a low frequency phase locked voltage controlled oscillator with the frequency multiplying technique. A phase processor based on field programmable gate array (FPGA) technology is designed for the heterodyne interferometer, and it contributes to real-time display of electron density. To extract phase information, a novel numerical algorithm related to fast Fourier transform is written on the FPGA chip and enables one to obtain phase shift without being affected by amplitude variation induced by plasma absorption or frequency modulation from the outer electromagnetic environment. The interferometer achieves minimum measurable electron density in the order of 1016 m-3. With the plasma diagnosis, electron density and low frequency tearing mode have been measured during the first experimental campaign.

A remote gain controlled and polarization angle tunable Doppler backward scattering reflectometer.

Remote control of the diagnostic systems is the basic requirement for the high performance plasma operation in a fusion device. This work presents the development of the remote control system for the multichannel Doppler backward scattering (DBS) reflectometers. It includes a remote controlled quasi-optical system and a remote intermediate frequency (IF) amplifier gain control system. The quasi-optical system contains a rotational polarizer, its polarization angle is tunable through a remote controlled motor, and it could combine the microwave beams with a wide frequency range into one focused beam. The remote IF gain control system utilizes the digital microcontroller (MCU) technique to regulate the signal amplitude for each signal channel. The gain parameters of amplifiers are adjustable, and the feedback of working status in the IF system will be sent to MCU in real time for safe operation. The gain parameters could be controlled either by the Ethernet remote way or directly through the local control interface on the system. Preliminary experimental results show the effectiveness of the remote controlled multichannel DBS system.

[Implications, spiritual characteristics and practical significance of Chinese schistosomiasis control culture].

The culture of schistosomiasis control is specific in the history of Chinese culture. Broadly speaking, the culture of schistosomiasis control is a summary of specific social mood, social consciousness and material culture created by Chinese populations during the progress of schistosomiasis control since the founding of the People's Republic of China. Narrowly speaking, the culture of schistosomiasis control is the spiritual culture that is jointly created and nurtured by schistosomiasis control workers since the founding of the People's Republic of China. The spiritual features of Chinese schistosomiasis control culture are characterized by the patriotism and care about the people, the matter-to-fact attitude, the pioneering and enterprising spirit, and the spirit of sacrifice and dedication. The ultimate goal of the research on the culture of schistosomiasis control is to facilitate the achievement of the strategic goal of Healthy China 2030 as scheduled, accelerate the progress towards elimination of schistosomiasis, and to promote the sustainable development of schistosomiasis control in China.

[Effect of integrated schistosomiasis control measures in Hunan Province from 2004 to 2019].

OBJECTIVE: To examine the effect of the integrated schistosomiasis control measures in Hunan Province from 2004 to 2019, so as to provide insights into the development of the schistosomiasis elimination strategy. METHODS: The integrated schistosomiasis control measures implemented by the health, agriculture, water resources, forestry, land and resources sectors were retrospectively collected in Hunan Province from 2004 to 2019, and the completion of each measure, cost of control measures, Schistosoma japonicum infections in humans and bovines, and snail status were analyzed each year. An index system for assessing the integrated schistosomiasis control effect was constructed using the Delphi method to calculate the integrated schistosomiasis control effect index. In addition, a cost-effect analysis was performed in terms of the decline in the prevalence of S. japonicum infections in humans and bovines, areas with snails in inner embankments, and areas with infected snails. RESULTS: A total of 7 110 926 500 Yuan were invested into the integrated schistosomiasis control program of Hunan Province from 2004 to 2019. During the 16-year period, a total of 277 437.12 hm2 snail habitats received molluscicidal treatments, 6 927 230 person-times given expanded chemotherapy, 2 116 247 bovine-times given expanded chemotherapy, 954 850 harmless toilets built, 290 359 bovines fenced, 136 666 bovines eliminated, 141 905 machines used to replace bovines, 39 048.63 hm2 water lands improved as dry lands, 724.12 km irrigation regions improved, 3 994 300 populations covered with safe water, 191 102.89 hm2 forests planted and 38 535.27 hm2 lands leveled. The prevalence of S. japonicum infections was 4.29% in humans and 4.48% in bovines in Hunan Province in 2004, with 2 449.37 hm2 snail habitats in inner embankments and 3 423.74 hm2 infected snail areas. In 2019, the prevalence of S. japonicum infections reduced to 0 in both humans and bovines, and areas of snail habitats reduced to 540.92 hm2 (77.92% reductions), while the areas with infected snails reduced to 0. The overall integrated schistosomiasis control effect index appeared a tendency towards a rise over years since 2004, and the integrated schistosomiasis control effect index was 97.35 in 2019; the annual mean costs for a 1% reduction in the prevalence of S. japonicum infections in 100 populations and 100 bovines were 70.11 Yuan and 4 204.78 Yuan, and the annual mean costs for a 1% reduction in the snail areas in inner embankments and infected snail areas were 2 010.20 Yuan and 1 298.09 Yuan, respectively. CONCLUSIONS: The integrated control measures achieve remarkable effectiveness for schistosomiasis control in Hunan Province, with a remarkable decline in the prevalence of S. japonicum infections in humans and bovines and great shrinking of snail areas in inner embankments and infected snail areas. Adequate fund investment is required to improve the integrated schistosomiasis control measures and consolidate the control achievements.

[Challenges and countermeasures of schistosomiasis control in Hunan Province in the new era].

This paper describes the current epidemic characteristics and endemic status of schistosomiasis, analyzes the main challenges of schistosomiasis control and proposes the emphasis and interventions for future schistosomiasis control activities in Hunan Province, so as to provide insights into the elimination of schistosomiasis in Hunan Province.

[Application of the exponential smoothing model and ARIMA model in prediction of the endemic situation of schistosomiasis in Hunan Province].

OBJECTIVE: To predict the changes in the prevalence of Schistosoma japonicum infections in humans and livestock in Hunan Province using the exponential smoothing model and the ARIMA model. METHODS: The data pertaining to S. japonicum infections in humans and livestock in Hunan Province from 1957 to 2015 were collected, and the exponential smoothing model and the ARIMA model were created using the software Eviews and PASW Statistics 18.0. In addition, the effectiveness of these two models for the prediction of S. japonicum infections in humans and livestock in Hunan Province from 2016 to 2018 was evaluated. RESULTS: The exponential smoothing model and the ARIMA model had a high goodness of fit for prediction of S. japonicum infections in humans and livestock in Hunan Province from 1957 to 2015. There was a linear trend in the prevalence of S. japonicum infections in humans and livestock in Hunan Province from 1957 to 2015. The prevalence of S. japonicum infections in humans predicted with the Brown's linear trend and the prevalence of S. japonicum infections in livestock predicted with the Holt's linear trend in Hunan Province from 2016 to 2018 fitted better the actual data than the ARIMA model; however, prediction of the ARIMA model indicated that the endemic situation of schistosomiasis remained at a low level in Hunan Province. CONCLUSIONS: At a low epidemic level, development of highly sensitive tools for monitoring schistosomiasis is urgently needed in Hunan Province to fit the current endemic situation, and the schistosomiasis control measures should be intensified to consolidate the control achievements.

[Difficulties and countermeasures for the perioperative management of megasplenectomy in patients with advanced schistosomiasis].

The etiology, pathology, clinical features and prognosis of megalosplenic advanced schistosomiasis have their specific features, and therefore, the perioperative management of this disorder has special countermeasures. The review analyzes the difficult problems in the perioperative management of megalosplenic advanced schistosomiasis, including ultra - low platelet counts, extensive and severe adhesive splenomegaly, massive hemorrhage during surgery and portal vein thrombosis, and proposes countermeasures to tackle these problems, with aims to guide the clinical treatment and cure of schistosomiasis, thereby improving the prognosis, reducing complications and improving the quality of life.