662 research outputs found
Classification-based forest management program and farmers' income : evidence from collective forest area in southern China
Purpose This article's purpose is to examine the effect of a Classification-Based Forest Management (CFM) program on farmers' income and determine whether its effect varies with the degree of farmers' concurrent occupations. Design/methodology/approach The authors use representative panel survey data from Longquan to explore the welfare effects of CFM on farmers. The analysis uses differences-in-differences with propensity score matching (PSM-DID) estimation techniques to deal with endogeneity problems when farmers make the decision to participate in CFM. Findings The results show that CFM has a positive effect on part-time forestry households (where forestry income accounts for between 5 and 50% of total income). In contrast, it has a negative impact on full-time forestry households (forestry income accounts for more than 50%), and no clear effect on nonforestry households whose forestry income is less than 5%. This research also shows that the positive effect of CFM on farmers' total income is mainly due to increase of off-farm income driven by CFM, while the negative effects consist of CFM's reduction of forestry income. Originality/value The extent of CFM's economic benefits to farmers is uncertain and largely unexplored. This paper analyzes the impact of CFM on income structure to explore the mechanisms explaining its effects on farmers' income. There are still challenges in ensuring the reliability and accuracy of CFM assessment. This paper collected natural experimental data and used the estimation technology of PSM-DID to solve the possible endogeneity problems.Peer reviewe
Experimental Study on Landslides of Loose Sediment Slope Induced by Stream Bed Incision
Uplift of the Qinghai-Tibetan Plateau has resulted in rapid incision of rivers along the margin of the plateau. Landslides occur frequently as a consequence of increasing bank slope and potential landslide energy due to stream bed incision or lateral bank erosion on the concave banks at bends. The Fencha Gully is on the eastern margin of the Qinghai-Tibetan Plateau and is developing on a huge landslide body. Flume experiments were conducted on the base of the field investigation to study the mechanism of landslides induced by stream bed incision. The experiments were designed with a length scale ratio of 1:20. Landslides and stream bed incision with loose sediment were observed and analyzed. The results show that landslides are induced as a result of stream bed incision. The potential landslide energy is defined, which increases quickly with an effective incision depth coupling vertical incision and lateral bank erosion. The occurrence of landslides can be attributed to increasing incision depth and potential landslide energy. Results indicate that the critical effective incision depth is 4.0–6.0 m. A critical value of the potential landslide energy is found from the experiments. Landslides occur if the potential energy exceeds the critical energy, which is 2.24×104 t·m/s2 for the Fencha Gully. The incision depth and potential energy of landslides from the Fencha Gully agree well with the results
Reviewing the role of gut microbiota in the pathogenesis of depression and exploring new therapeutic options
The relationship between gut microbiota (GM) and mental health is one of the focuses of psychobiology research. In recent years, the microbial-gut-brain axis (MGBA) concept has gradually formed about this bidirectional communication between gut and brain. But how the GM is involved in regulating brain function and how they affect emotional disorders these mechanisms are tenuous and limited to animal research, and often controversial. Therefore, in this review, we attempt to summarize and categorize the latest advances in current research on the mechanisms of GM and depression to provide valid information for future diagnoses and therapy of mental disorders. Finally, we introduced some antidepressant regimens that can help restore gut dysbiosis, including classic antidepressants, Chinese materia medica (CMM), diet, and exogenous strains. These studies provide further insight into GM’s role and potential pathways in emotion-related diseases, which holds essential possible clinical outcomes for people with depression or related psychiatric disorders. Future research should focus on clarifying the causal role of GM in disease and developing microbial targets, applying these findings to the prevention and treatment of depression
The role of microbiota in the development and treatment of gastric cancer
The stomach was once considered a sterile organ until the discovery of Helicobacter pylori (HP). With the application of high-throughput sequencing technology and macrogenomics, researchers have identified fungi and fivemajor bacterial phyla within the stomachs of healthy individuals. These microbial communities exert regulatory influence over various physiological functions, including energy metabolism and immune responses. HP is a well-recognized risk factor for gastric cancer, significantly altering the stomach’s native microecology. Currently, numerous studies are centered on the mechanisms by which HP contributes to gastric cancer development, primarily involving the CagA oncoprotein. However, aside from exogenous infections such as HP and EBV, certain endogenous dysbiosis can also lead to gastric cancer through multiple mechanisms. Additionally, gut microbiota and its metabolites significantly impact the development of gastric cancer. The role of microbial therapies, including diet, phages, probiotics and fecal microbiota transplantation, in treating gastric cancer should not be underestimated. This review aims to study the mechanisms involved in the roles of exogenous pathogen infection and endogenous microbiota dysbiosis in the development of gastric cancer. Also, we describe the application of microbiota therapy in the treatment and prognosis of gastric cancer
Experimental study on control of Limnoperna fortunei biofouling in water transfer tunnels
The golden mussel (Limnoperna fortunei) is a filter-collector macroinvertebrate species originating from southern China. It easily invades water transfer tunnels and attaches onto tunnel walls and structures with extremely high density, resulting in biofouling, pipe clogging, structure corrosion, a decrease in water transfer efficiency, and water pollution. It has become a prevalent problem and has caused concern all over the world. However, an effective and environment friendly method of controlling golden mussel invasion has not yet been approved. This study is aimed to propose measures for preventing golden mussel invasion and biofouling in the water transfer tunnels of the East River Water Source Project (ERWSP), which transfers water from the East River to Shenzhen, southern China for 10 million people. Long-term samplings and observations of the East River water were performed to study the golden mussel's invading pattern. Flume experiments were done to study the golden mussel's attachment on 14 different materials and performance in turbulent flows. An integrated ecological prevention pool was designed and constructed based on the flume experimental results for preventing the golden mussel invasion in the scale model tunnels of the ERWSP. The major technology of the ecological pool was preventing the golden mussel from entering the tunnels by attracting veligers to attach on geotextile cloth, attracting mussels to attach on bamboo, and killing veligers with high-frequency turbulence. An eight-month application experiment showed that the ecological pool successfully controlled the golden mussel invasion and biofouling in the scale model tunnels. The mussel density on the attachment materials decreased sharply as the distance of the materials from the pool entrance increased; the turbulence was effective in killing veligers that escaped from the attachment materials. No mussel was found on the model tunnels. Thus, the integrated ecological prevention pool is recommended as a successful measure for controlling the golden mussel invasion and biofouling in water transfer tunnels.Facultad de Ciencias Naturales y Muse
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