The next widespread bamboo flowering poses a massive risk to the giant panda

The IUCN Red List has downgraded several species from “endangered” to “vulnerable” that still have largely unknown extinction risks. We consider one of those downgraded species, the giant panda, a bamboo specialist. Massive bamboo flowering could be a natural disaster for giant pandas. Using scenario analysis, we explored possible impacts of the next bamboo flowering in the Qinling and Minshan Mountains that are home to most giant pandas. Our results showed that the Qinling Mountains could experience large-scale bamboo flowering leading to a high risk of widespread food shortages for the giant pandas by 2020. The Minshan Mountains could similarly experience a large-scale bamboo flowering with a high risk for giant pandas between 2020 and 2030 without suitable alternative habitat in the surrounding areas. These scenarios highlight thus-far unforeseen dangers of conserving giant pandas in a fragmented habitat. We recommend advance measures to protect giant panda from severe population crashes when flowering happens. This study also suggests the need to anticipate and manage long-term risks to other downgraded species

Analysis on Characteristics of Vegetation and Soil Bacterial Community under 20 Years’ Restoration of Different Tree Species: A Case Study of the Qinling Mountains

Afforestation with different tree species formed different vegetation patterns, and altered soil properties and the composition and diversity of the soil bacterial community. In order to analyze the difference characteristics of vegetation, soil and bacterial community after 20 years’ restoration of different tree species, we investigated changes in vegetation (tree, shrubs, and herbs), soil properties and the soil bacterial community composition in the topsoil (0–10 cm) following afforestation of P. asperata Mast. and L. kaempferi (Lamb.) Carr.on the southern slope of the Qinling mountains. The results showed that, within a 20-year recovery period, the restorative effect of L. kaempferi was better than that of P. asperata, for alpha diversity and biomass of vegetation, composition and diversity of soil bacterial community were all preferable under nearly same environmental conditions if just taking these indices into consideration. Additionally, biodiversity of L. kaempfer was much richer than that of P. asperata. Our observations suggest that soil physicochemical properties, soil bacterial community composition and diversity following afforestation were mainly affected by tree species. The results could explain our hypothesis to some extent that a planted forest with quick growth speed and sparse canopy has higher biomass productivity and alpha diversity of ecosystem

Pressure drop rate threshold setting of block valves in hydrogen-blended natural gas pipelines

The mixing of hydrogen will increase the leakage and explosion risk of natural gas pipelines. However, the pressure drop rate threshold of existing block valve in natural gas pipeline cannot meet the safety requirements of hydrogen-blended natural gas pipeline transportation. Thereby, the pressure drop rate of the pipeline block valves under the leakage and distribution conditions was simulated and calculated by the SPS software, then a method for setting of the pipeline threshold was developed so that the changing rules of the pressure drop rate of the block valves and its appropriate threshold were gained by simulation under six influencing factors, and further the formulas for the pressure drop rate thresholds of the block valves were formed by fitting for pure gas and 10% hydrogen bending ratio natural gas pipelines respectively. The results show that: after the pipeline leaks, the upstream and downstream pressure drop rates increase with the increasing of the hydrogen blending ratio. The threshold of pressure drop rate increases with the hydrogen blended. The leakage position, pressure and length of the pipelines have great effect on the pressure drop rate threshold, but the flow, the pipeline diameter and the diameter of the leakage holes have little effect on the pressure drop rate threshold. Moreover, the calculated results of the threshold fitting formula are in good agreement with the simulation results. So, the research results could provide theoretical guidance for improving the intrinsic safety of the hydrogen-blend natural gas pipeline

Genetic associations with longevity are on average stronger in females than in males

It is long observed that females tend to live longer than males in nearly every country. However, the underlying mechanism remains elusive. In this study, we discovered that genetic associations with longevity are on average stronger in females than in males through bio-demographic analyses of genome-wide association studies (GWAS) dataset of 2178 centenarians and 2299 middle-age controls of Chinese Longitudinal Healthy Longevity Study (CLHLS). This discovery is replicated across North and South regions of China, and is further confirmed by North-South discovery/replication analyses of different and independent datasets of Chinese healthy aging candidate genes with CLHLS participants who are not in CLHLS GWAS, including 2972 centenarians and 1992 middle-age controls. Our polygenic risk score analyses of eight exclusive groups of sex-specific genes, analyses of sex-specific and not-sex-specific individual genes, and Genome-wide Complex Trait Analysis using all SNPs all reconfirm that genetic associations with longevity are on average stronger in females than in males. Our discovery/replication analyses are based on genetic datasets of in total 5150 centenarians and compatible middle-age controls, which comprises the worldwide largest sample of centenarians. The present study's findings may partially explain the well-known male-female health-survival paradox and suggest that genetic variants may be associated with different reactions between males and females to the same vaccine, drug treatment and/or nutritional intervention. Thus, our findings provide evidence to steer away from traditional view that “one-size-fits-all” for clinical interventions, and to consider sex differences for improving healthcare efficiency. We suggest future investigations focusing on effects of interactions between sex-specific genetic variants and environment on longevity as well as biological function