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The Nanling Mountains, an important mountain range and watershed in south China, harbor a wealth of relictual plant species, and are considered a 'museum' of subtropical biodiversity. With respect to birds, however, the roles of the Nanling Mountains in impeding the dispersal of the subtropical birds and, as a result, shaping their population and community structures have received little consideration. To examine these roles, we compiled and analyzed two datasets. 1) To test the mountains' influence on gene flow, we undertook a comparative phylogeographic study comparing mitochondrial COI and Cytb DNA sequences of five sylvioid resident bird species of the mountains (Huet's fulvetta Alcippe hueti, red‐billed leiothrix Leiothrix lutea, greater necklaced laughingthrush Pterorhinus pectoralis, Indochinese yuhina Staphida torqueola and mountain bulbul Ixos mcclellandii). 2) To examine differential community development over the history of modern birds, we examined distributional data of all species of the Nanling region using public species occurrence records. For part 1), we sampled 327 individuals from 36 sites and conducted correlation analysis of genetic and geographic distances, taking into account the landscape of the mountains. We found that the mountains do not seriously impede gene flow among populations but influenced species differently. For part 2), comparative analysis of 446 species in 81 families indicated that family membership influenced the community composition of birds in Nanling region. Variation in family distributions is attributable to both environmental and evolutionary factors. Overall, we found that the Nanling Mountains are not currently a substantial barrier to gene flow among the species we studied but act as a corridor and refuge for these birds. However, analyses on higher ranked community data suggest the mountains acted as a barrier in older times, corresponding to the known diversification events in southeast Asian avifauna. [ABSTRACT FROM AUTHOR]

We investigated the effects of 12-week brisk walking on chronotropic response in hypertensive patients aged 40–69. 77 participants in exercise group underwent 12-week brisk walking, while 66 participants in control group received health education. Chronotropic parameters, resting blood pressure, and physical fitness including peak oxygen consumption (VO2peak) were measured. After 12 weeks, the systolic blood pressure (SBP) was decreased (−6.104 mmHg, 95%CI −8.913 to −3.295 mmHg, P<0.0001), while metabolic chronotropic relationship (MCR) slope and VO2peak were increased (0.073, 95%CI 0.001 to 0.145, P=0.046; 1.756 mL/kg/min, 95%CI 0.891 to 2.622 mL/kg/min, P<0.0001) in exercise group compared to baseline. The chronotropic response index (CRI) at 25–75 W load were decreased (−0.210, 95%CI −0.307 to −0.112, P<0.0001; −0.144, 95%CI − 0.204 to −0.083, P<0.0001; −0.078, 95%CI −0.135 to −0.022, P=0.007) in control group after 12 weeks. The relative changes (%Δ) of systolic and diastolic blood pressure were negatively correlated with %ΔVO2peak (r=−0.233, r=−0.187), while %ΔMCR and %ΔCRI at 50–75 W load were positively correlated with %ΔVO2peak after 12 weeks (r=0.330, r=0.282, r =0.370). %ΔSBP was also positively correlated with %ΔMCR (r =−0.213). In conclusion, 12-week brisk walking reduced SBP by improving chronotropic response in hypertensive patients aged 40–69. The enhanced chronotropic response was associated with enhanced cardiorespiratory fitness. [ABSTRACT FROM AUTHOR]