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Recognizing watershed runoff process and its component sources is a prerequisite for the rational use of water resources. To elucidate the effects and quantitative contributions of various vegetation types on the components of watershed runoff, we centered on the Caijiachuan main channel watershed in Jixian, Shanxi and five sub-watersheds with distinct vegetation types. By tracking the hydrological responses to two representative rainfall events and assessing the spatiotemporal variations in hydrogen and oxygen isotope signatures, we aimed to discern disparities in the runoff processes across these sub-watersheds and pinpoint their constituent origins. The results showed that under medium rainfall condition, the contribution rates of event water to the river flow of each watershed were in an order of protected forest (94.3%) > Caijiachuan main channel (83.1%) > agro-pastoral composite (64.3%) > plantation-secondary forest (52.4%) > cropland (0.3%) > secondary forest (0.0%) ; under light rainfall condition, plantation-secondary forest (52.4%) > protected forest (58.5%) > cropland (40.6%) > secondary forest (15.8%) > agro-pastoral composite (12.5%) > Caijiachuan main channel (9.3%). The event water contribution rate of secondary forest and protected forest watersheds to runoff was higher than that of plantation watersheds. The secondary forests watersheds had a stronger runoff storage capacity. The event water contribution rate of protected forest and agro-pastoral composite watersheds under medium rainfall intensity condition was greater than that under light rainfall intensity condition, while the event water contribution rate of cropland, plantation-secondary forest, and secondary forest watersheds was in adverse. The event water contribution to the runoff of forested watersheds was greater than that of cropland watersheds, which may be related to the presence of silt dams at the mouth of agricultural watershed channels. This study can provide a scientific basis for the analysis of water conservation and runoff change attribution in the loess area of west Shanxi. [ABSTRACT FROM AUTHOR]

Porcine parvovirus (PPV) is an important pathogen causing reproductive failure in pigs. PPV-induced cell apoptosis has been recently identified as being involved in PPV-induced placental tissue damages resulting in reproductive failure. However, the molecular mechanism was not fully elucidated. Here we demonstrate that PPV nonstructural protein 1 (NS1) can induce host cell apoptosis and death, thereby indicating the NS1 may play a crucial role in PPV-induced placental tissue damages and reproductive failure. We have found that NS1-induced apoptosis was significantly inhibited by caspase 9 inhibitor, but not caspase 8 inhibitor, and transfection of NS1 gene into PK-15 cells significantly inhibited mitochondria-associated antiapoptotic molecules Bcl-2 and Mcl-1 expressions and enhanced proapoptotic molecules Bax, P21, and P53 expressions, suggesting that NS1-induced apoptosis is mainly through the mitochondria-mediated intrinsic apoptosis pathway. We also found that both PPV infection and NS1 vector transfection could cause host DNA damage resulting in cell cycle arrest at the G1 and G2 phases, trigger mitochondrial ROS accumulation resulting in mitochondria damage, and therefore, induce the host cell apoptosis. This study provides a molecular basis for elucidating PPV-induced cell apoptosis and reproductive failure. [ABSTRACT FROM AUTHOR]

Objective: Our study is to analyse the coinfection effects of porcine circovirus type 2 (PCV2) and porcine parvovirus (PPV) in vivo on phagocytosis and interferon mRNA expression level of porcine alveolar macrophages (PAM)., Methods: Forty-eight 5-week-old healthy piglets were divided randomly into 4 groups of 12 (PCV2, PPV, PCV2/PPV and the control groups). The piglets in PCV2 group were inoculated oronasally with 3 mL of porcine circovirus type2 (PCV2, 10(5.61) TCID50/0.1 mL), PPV group with 3 mL of porcine parvovirus (PPV, 10(6.69) TCID50/0.1 mL), PCV2/PPV group with 3 mL of PCV2 and 3 mL of PPV and the control group with 3 mL of cell culture medium, respectively. Three piglets from each group were sacrificed randomly on 3, 7, 14 and 35 day post infection (dpi) and porcine alveolar macrophages (PAM) were collected to detect viability, phagocytotic capabilities and alpha1- and gamma-interferon (IFN-alpha1 and IFN-gamma) mRNA levels of PAM., Results: The viabilities of PAM from PCV2 group and PCV2/PPV group became weaker than that of control group during the period of 3 - 14 dpi but they were similar to that of control group on 35 dpi; there was no significant difference between the viability of PCV2/PPV group and that of PCV2 group (P > 0.05). The phagocytotic capabilities of PAM from three virus infection groups were lower than that of control group (P < 0.01), among which that of PCV2/PPV group descended more drastically. IFN-alpha1 and IFN-gamma mRNA levels in PAM from PCV2/PPV group were significantly lower than those of PCV2, PPV and control groups (P < 0.01)., Conclusion: PCV2/PPV co-infection did not cause further decline of PAM viability but strongly weakened phagocytosis and constantly lowered IFN (IFN-alpha1 and IFN-gamma) mRNA expression levels of PAM.