ABSTRACT
To establish a method for simultaneous detection of porcine circovirus type 2 (PCV2) and porcine circovirus type 3 (PCV3), specific primers and TaqMan probes were designed after sequence alignment according to the specific sequences of PCV2 Cap gene and PCV3 Cap gene on GenBank. By optimizing the reaction conditions, a duplex fluorescence quantitative PCR detection method for simultaneous detection of porcine circovirus type 2 and 3 was established, and the specificity, sensitivity, and reproducibility were tested. Specificity test results showed that in addition to the positive test results for PCV2 and PCV3, tests for PRRSV, CSFV, PPV, PRV, PEDV, and TGEV were all negative with no cross-reaction, indicating its good specificity. Sensitivity test results showed that the minimum detection limit for detection of PCV2 and PCV3 can both reach 10 copies.L-1, indicating its high sensitivity. The coefficient of variation within and between groups of this method was less than 2%, indicating its good stability. A total of 181 pork and whole blood samples collected from Zhejiang Province were tested using the detection method established in this article and the standard common fluorescent PCR detection method. The results showed that the positive rate of PCV2 was 50.83% (92/181), the positive rate of PCV3 was 37.57% (68/181), and the co-infection rate of PCV2 and PCV3 was 12.15% (22/181). The above detection results of ordinary fluorescent PCR were 50.28% (91/181), 36.46% (66/181), and the co-infection rate was 11.60% (21/181). The coincidence rates of the two methods for PCV2 and PCV3 can reach 98.91% and 97.06%, and the coincidence rate for PCV2 and PCV3 mixed infection were 95.45%. In summary, the duplex fluorescence quantitative PCR detection method established in this experiment can distinguish PCV2 and PCV3 rapidly, which can be used for pathogen detection and epidemiological investigation.
ABSTRACT
Since reform and opening-up, China's eastern coastal cities have taken the lead in integrating into the global production network and city network based on neoliberalism and economic globalization. Entering the 21st-Century, the deep inland cities in Western China (DICWC), which are underdeveloped at the national scale, are keeping with the Belt and Road Initiative and high-quality development strategy and exploring the localization path of urban globalization. Among them, Xining and Yinchuan, the two provincial capitals, have adopted the urban globalization process driven by the sports festival and cultural festival of the 'Tour of Qinghai Lake';and the 'China-Arab States Expo';, respectively. Based on the field research data, this paper summarizes and compares the globalization paths and effects of Xining and Yinchuan driven by international festivals. The main conclusions include: Firstly, the international festivals are (central/provincial/autonomous region/city) power-led, that is, the government tries to promote the integration of inland areas into globalization, and they are powerful tools and strategies to promote the process of urban globalization and local social and economic development. International festivals can enhance the city's political and cultural influence and effectively promote the city's integration into the global system. In contrast, the 'China-Arab States Expo';as a political, cultural, and economic exchange platform can promote the economic globalization of the cities more than the 'Tour of Qinghai Lake';as a sports festival. Secondly, the actor-network in international festivals in inland cities is very distinct, with the government as the leader (initiator, organizer, and executor), enterprises as the specific participants, the media as the booster of news reports and the public as the indirect and passive participant. Thirdly, from the perspective of urban globalization, the 'Tour of Qinghai Lake';is only a sports festival, however, the political intervention and economical guidance of the 'China-Arab States Expo';is more obvious and direct. Fourthly, international festivals in inland cities established a new global image by promoting the modernization drive of city facilities, especially creating a new international urban space. However, the model of the international festival-driven globalization of DICWC is still in the primary stage. Moreover, after the outbreak of COVID-19 in 2019, the globalization of Xining and Yinchuan, driven by the sports event and cultural festival, has been impacted to varying degrees. The city urgently needs to seek a more stable driving model to promote its own globalization development. The 'economical marginal effect';of international festivals in inland cities is declining. Therefore, the urban globalization of DICWC needs the related further innovations in organization and the improvement of the stability of international festivals.