Species and structural diversity of trees at the structural type level.

Background: Species and structural diversity are important for understanding the formation of forest communities, key ecological processes, and improving forest ecological functions and services, but their spatial characteristics have received little attention. Based on the spatial relationships among neighbouring trees, we proposed to divide trees within a structural unit into 15 structural types, and used the univariate distributions of the uniform angle index (W), mingling (M), and dominance (U), along with four common species diversity indices, to analyse the diversity of structural types in natural forests near the Tropic of Cancer.

Results: Only a portion of clumped class maintained aggregation, most exhibited a random pattern.

Diagnostic Accuracy of JES Classification for Prediction of Invasion Depth in Superficial Esophageal Squamous Carcinoma: Meta-Analysis.

Prediction of the depth of invasion in superficial oesophageal squamous carcinoma (SESC) is an important factor for choosing the treatment. Recently, the Japan Esophageal Society (JES) designed a magnifying endoscopy classification based on the Inoue and Arima classifications. The aim of this study was to conduct a meta-analysis of the published literature on JES classification.

Effect of Reinforced Video by WeChat on Adenoma Detection Rate for Colonoscopy.

Objective: To evaluate the influence of reinforced educational video through smartphone WeChat on adenoma detection rate (ADR).

Study Design: Randomised controlled study. Place and Duration of the Study: Department of Gastroenterology, Xiantao First People's Hospital affiliated to Yangtze University, Hubei, China, from May 2020 to December 2021.

Exposed Rock Reduces Tree Size, but Not Diversity.

Karst made up of limestone is widely considered a "Noah's ark" of biodiversity. Rock and soil substrates comprise two different site types in karst terrain, although both can support dense forests. However, it is unclear whether and how the presence of exposed rock affects forest diversity and tree size.

The Abundance and Structure of Deadwood: A Comparison of Mixed and Thinned Chinese Fir Plantations.

The sustainability of coniferous monoculture plantations is facing challenges with respect to yields, ecology, and biodiversity. Conversion of monocultural coniferous plantations into mixed stands using thinning or direct mixed planting is widely considered to be a key strategy for overcoming these challenges and transforming the characteristics of plantations on a regional scale. Substantial amounts of deadwood may be produced in mixed forests (MFs); this material is important for evaluating and modifying forest management methods, understanding the dynamics of forest stands, and achieving biodiversity conservation.

The effect of using simethicone with or without N-acetylcysteine before gastroscopy: A meta-analysis and systemic review.

Background/aim: To assess the efficacy and safety of simethicone with or without N-acetylcysteine (NAC) as premedications before gastroscopy.

Materials And Methods: We searched EMBASE, PubMed, Cochrane library and Web of Science database for randomized clinical controlled trials regarding simethicone ± NAC as oral drinking agents before gastroscopy. Statistical software RevMan5.

[Stand density estimation based on the measurement of spatial structure].

This study estimated stem density by combining distance sampling with stand spatial structure investigation techniques. We tested the statistical performance of two investigative methods (selecting the fourth- or sixth-nearest tree to the sample location) and three different density estimators (Prodan, Persson and Thompson). Different spatial distribution patterns influenced the performance of these estimators.

Above- and below-ground carbon stocks in an indigenous tree (Mytilaria laosensis) plantation chronosequence in subtropical China.

More than 60% of the total area of tree plantations in China is in subtropical, and over 70% of subtropical plantations consist of pure stands of coniferous species. Because of the poor ecosystem services provided by pure coniferous plantations and the ecological instability of these stands, a movement is under way to promote indigenous broadleaf plantation cultivation as a promising alternative. However, little is known about the carbon (C) stocks in indigenous broadleaf plantations and their dependence on stand age.