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In recent decades, Southwest China (SWC) has suffered from frequent super droughts, leading to severe economic losses and ecological degradation. This study investigates the characteristics of super droughts in SWC during 1961–2022, reveals the compounding effect of multiscalar anomalies, and explores the plausible atmospheric circulation mechanisms responsible. The nature of super drought is a compound drought caused by the superposition of extreme drought events across multiple time scales. By contrasting the typical drought cases in 2006 and 2022, the decisive role of multiscalar drought compounding is confirmed. Based on the Comprehensive Multiscalar Index (CMI), multiple super drought events in SWC were identified to be temporally clustered during 2006–2014. Among them, the decadal background of enhanced evaporation and precipitation deficit at long time scales is a necessary condition for shaping the overall pattern of super droughts, while the precipitation and evaporation anomalies at short time scales trigger the outbreak of super droughts, determining the exact timing of occurrence. These events include August–September 2006, November 2009 to May 2010, July–October 2011, April–May 2012, January–April 2013, etc. Statistical results suggest that the contribution of superposed precipitation anomalies to super drought is 2.4 times that of evaporation. As regards the circulation mechanisms affecting multiscalar precipitation, the anomalous spatial patterns at short-term and long-term scales are similar, featuring the cyclonic circulation over the South China Sea and the northeasterly wind anomalies together with the subsidence center over SWC. During 2006–2014, the possible causes for the cross-seasonal persistent precipitation reduction in SWC are the extreme negative phase of the Pacific Decadal Oscillation (PDO) in the North Pacific as well as the pronounced warming of the warm pool in the western Pacific. The key dynamic processes are outlined as follows. On the one hand, the negative PDO phase generates anomalous anticyclonic circulation in the North Pacific, with the northeasterly winds on its southwest flank extending to Southeast Asia, hindering moisture transport into SWC. On the other hand, the warming of the warm pool excites anomalous cyclonic circulation to its northwest, also giving rise to northeasterly wind anomalies over SWC. Meanwhile, the ascending motion over the warm pool region diverges at upper levels with outflows converging aloft over SWC, which further induces compensating downward motion there. The combined effect of the above two remote forcings establishes a climatic background state unfavorable for precipitation over SWC at long time scales, thus constituting a crucial prerequisite for the superimposition of short-term precipitation anomalies to develop into super droughts. [ABSTRACT FROM AUTHOR]

Objective: To compare balance ability between elderly individuals who practiced Tai-Chi-Chuan (TCC) for average 9.64 years and elderly individuals who did not practice TCC and its relationship with lower extremity muscle strength and ankle proprioception. Methods: Twenty-five elderly volunteers were divided into two groups according to their TCC practcing experience. Sixteen were TCC group and the other nine were control population. Subjects completed a static balance test and ankle proprioception test using a custom-designed evaluation system, and concentric and eccentric knee extensor and flexor muscle strength tests. Subjects stood on the plate form to measure the proprioception in functional standing position which was differed from the previous studies. Multiple linear regressions were also used to predict the important factor affecting balance. Results: TCC group performed better than the control group in balance, proprioception, and muscle strength of lower extremity. The proprioception was the most important factor related to balance ability and it can be accounted for explaining 44% of variance in medial-lateral sway direction, and 53% of variance in antero-posterior sway direction. The proprioception may be a more important factor which affecting the balance ability. Conclusion: TCC training is recommended to the elders; as it can improve balance ability through better proprioception. [ABSTRACT FROM AUTHOR]

Avian coccidiosis is a disease caused by members of the genus Eimeria. Huge economic losses incurred by the global poultry industry due to coccidiosis have increased the need for cost-effective and easily available recombinant vaccines. Microneme protein 2 (MIC2) and surface antigen 1 (SAG1) of E. tenella have been recognised as potential vaccine candidates. However, the genetic diversity of the antigens in field isolates, which affects vaccine efficacy, has yet to be largely investigated. Here, we analysed genetic diversity and natural selection of etmic2 and etsag1 in Korean E. tenella isolates. Both genes exhibited low levels of genetic diversity in Korean isolates. However, the two genes showed different patterns of nucleotide diversity and amino acid polymorphism involving the E. tenella isolates obtained from different countries including China and India. These results underscore the need to investigate the genetic diversity of the vaccine candidate antigens and warrant monitoring of genetic heterogeneity and evolutionary aspects of the genes in larger numbers of E. tenella field isolates from different geographical areas to design effective coccidial vaccines. [ABSTRACT FROM AUTHOR]

Abstract: Sequence analyses on the intron from the elongation factor-1α gene were conducted to examine the population structure and historical demography of whiskered velvet shrimp (Metapenaeopsis barbata) off China and Taiwan. Five samples including 155 individuals were separately collected from the north of East China Sea (ECS), waters off Taichung (TC), Cheding (CD), Xiamen (XM) and Hongkong (HK) and 41 alleles were identified. All F ST values between five samples were significant except the pair of TC-CD. Neighbor-joining tree and network of 41 alleles showed no significant genealogical structure. UPGMA tree of five sampling areas showed three distinct groups. One included the NECS; another contained TC and CD; the other included HK and XM. Both Tajima’s D and Fu’s F statistics and analysis of mismatch distribution for overall alleles suggested that this species in studied areas had experienced population expansion. [Copyright &y& Elsevier]