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The effects of disturbance on spatial patterns and species interactions provide critical information on community structure and species coexistence. Two standard plots of 1-ha were set, one of them was a sample plot with retrograde succession after disturbance, and the other one was undisturbed. Spatial indices and Spatial patterns statistics were used to analyze the spatial pattern and inter-specific correlation of main tree species in two plots. Our results showed that the diameter distributions of different species have reverse J-shape, unimodal and bimodal distribution in the disturbed plot, while bell-shaped curves were observed in the undisturbed plot. The distributions of tree species were mainly showed clustered patterns in almost all scales through univariate pair correlation function. Some similar results of the classification of Wiegand scheme of species association consistent with the consequences of the bivariate pair correlation. The mark variograms showed positive autocorrelation at a coarse scale. The current study may aid in efforts of forest management planning and ecosystem services. Meanwhile, different research methods of spatial distribution also help to improve the accuracy of spatial distribution and the interspecific association of tree species.

The mortality of trees across diameter class model is a useful tool for predicting changes in stand structure. Mortality data commonly contain a large fraction of zeros and general discrete models thus show more errors. Based on the traditional Poisson model and the negative binomial model, different forms of zero-inflated and hurdle models were applied to spruce-fir mixed forests data to simulate the number of dead trees. By comparing the residuals and Vuong test statistics, the zero-inflated negative binomial model performed best. A random effect was added to improve the model accuracy; however, the mixed-effects zero-inflated model did not show increased advantages. According to the model principle, the zero-inflated negative binomial model was the most suitable, indicating that the “0” events in this study, mainly from the sample “0”, i.e., the zero mortality data, are largely due to the limitations of the experimental design and sample selection. These results also show that the number of dead trees in the diameter class is positively correlated with the number of trees in that class and the mean stand diameter, and inversely related to class size, and slope and aspect of the site.

To identify the sapling species that can be planted in spruce–fir forest in the Changbai Mountains, China, we analyzed the associations among saplings and between saplings and adult trees of 4 tree species (spruce [Picea koraiensis Nakai], fir [Abies nephrolepis (Trautv.) Maxim.], Korean pine [Pinus koraiensis Sieb. et Zucc.], and lime [Tilia amurensis Rupr.]), and the spatial distribution of saplings under the adult trees. We observed positive associations between the saplings and adult trees of spruce, fir, Korean pine, and lime. In addition, the numbers of saplings of spruce, fir, Korean pine, and lime with distance from adult trees exhibited a positively skewed distribution. We conclude that saplings of any one or several of these 4 species can be planted in the mixed forests and the optimum distance between saplings and adults trees of the coniferous species is 2–3 m, whereas the corresponding optimal distance from the broadleaved lime is 4–5 m. Our results provide new insights into the development of reforestation techniques in spruce–fir forests in the Changbai Mountains.

China contains 119 million hectares of natural forest, much of which is secondary forest. An accurate estimation of the biomass of these forests is imperative because many studies conducted in northeast China have only used primary forest and this may have resulted in biased estimates. This study analyzed secondary forest in the area using information from a forest inventory to develop allometric models of the aboveground biomass (AGB). The parameter values of the diameter at breast height (DBH), tree height (H), and crown length (CL) were derived from a forest inventory of 2,733 trees in a 3.5 ha plot. The wood-specific gravity (WSG) was determined for 109 trees belonging to ten species. A partial sampling method was also used to determine the biomass of branches (including stem, bark and foliage) in 120 trees, which substantially easy the field works. The mean AGB was 110,729 kg ha–1. We developed four allometric models from the investigation and evaluated the utility of other 19 published ones for AGB in the ten tree species. Incorporation of full range of variables with WSG-DBH-H-CL, significantly improved the precision of the models. Some of models were chosen that best fitted each tree species with high precision (R2 = 0.939, SEE 0.167). At the latitude level, the estimated AGBof secondary forest was lower than that in mature primary forests, but higher than that in primary broadleaf forest and the average level in other types of forest likewise. 

China contains 119 million hectares of natural forest, much of whichis secondary forest. An accurate estimation of the biomass of these forests is imperative because many studies conducted in northeast China have only used primary forest and this may have resulted in biased estimates. This study analyzed secondary forest in the area using information from a forest inventory to develop allometric models of the aboveground biomass (AGB). The parameter values of the diameter at breast height (DBH), tree height (H), and crown length (CL) were derived from a forest inventory of 2,733 trees in a 3.5 ha plot. The wood-specific gravity (WSG) was determined for 109 trees belonging to ten species. A partial sampling method was also used to determine the biomass of branches (including stem, bark and foliage) in 120 trees, which substantially ease the field works. The mean AGB was110,729 kg ha–1. We developed four allometric models from the investigation and evaluated the utility of other 19 published ones for AGB in the ten tree species. Incorporation of full range of variables with WSG-DBH-H-CL, significantly improved the precision of the models. Some of models were chosen that best fitted each tree species with high precision (R2 ≥ 0.939, SEE 0.167). At the latitude level, the estimated AGB of secondary forest was lower than that in mature primary forests, but higher than that in primary broadleaf forest and the average level in other types of forest likewise.

The objective of the study was to introduce a simultaneous approach to extracting growth trends from diameter increment series by combining tree- and stand-level information in the framework of mixed-effects modeling. The model results are compared with those of the sequential modeling approach according to Yue et al. Can J For Res 41:1577–1589, (2011). Comprehensive data from periodically repeated tree and stand measurements on 113 Norway spruce long-term forest research stands distributed throughout southwestern Germany as well as annually resolved diameter growth data from stem analysis of 581 sample trees are used for model parameterization. Results provide clear evidence for distinct temporal variation due to environment-related effects after accounting for tree- and stand-level effects on diameter growth of Norway spruce over the past 136 years, with especially high growth levels during the last four decades. Most remarkable is the considerable increase in diameter growth rates following the 1947–1952 growth depression. From the early 1960s onwards, growth rates fluctuated on an elevated level until most recent years. Model comparison reveals that results of the sequential and simultaneous modeling approaches are similar with respect to the course of the time-specific environmental effects on growth. We conclude that the proposed simultaneous modeling approach has the advantages of extracting growth trends at a higher level of precision and being the more parsimonious modeling option.

Sampling is a key technique in comprehensive forest resources monitoring. The history of the sampling survey was briefly reviewed and sampling theories were classified and compared in detail. On the basis of that, the application of different sampling methods in comprehensive forest resources monitoring was illustrated in accordance with the sampling classification of Michael Köhl et al. Improvement of the sampling system in China was discussed to meet the new requirements of forest monitoring.

Staphylococcus aureus is a common human bacterium that sometimes becomes pathogenic, causing serious infections. A key feature of S. aureus is its ability to acquire resistance to antibiotics. The presence of the staphylococcal cassette chromosome （SCC） element in serotypes of S. aureus has been confirmed using multiplex PCR assays. The SCC element is the only vector known to carry the mecA gene, which encodes methicillin resistance in S. aureus infections. Here, we report the genome se- quence of a novel methicillin-sensitive S. aureus （MSSA） strain： SCC-like MSSA463. This strain was originally erroneously serotyped as methicillin-resistant S. aureus in a clinical laboratory using multiplex PCR methods. We sequenced the genome of SCC-like MSSA463 using pyrosequencing techniques and compared it with known genome sequences of other S, aureus iso- lates. An open reading frame （CZ049; AB037671） was identified downstream of attL and attR inverted repeat sequences. Our results suggest that a lateral gene transfer occurred between S. aureus and other organisms, partially changing S. aureus infec- tivity. We propose that attL and attR inverted repeats in S. aureus serve as frequent insertion sites for exogenous genes.

Three‐dimensional (3D) printing has received extensive attention due to its unique multidimensional functionality and customizability and has been recognized as one of the most revolutionary manufacturing technologies. Functional 3D printed products represent an important orientation for next‐generation manufacturing and attract a great spotlight for the application in sensors, actuators, robots, electronics, and medical devices. However, the lack of functions of printing polymeric materials dramatically limits the development of functional 3D printing. Different from traditional processing, the physical properties, such as geometry and rheological behavior, of the polymeric materials must match the printing process, making the selection of printable materials limited. More importantly, challenges in large‐scale production of such materials further stifle the development of functional 3D printing industry. In this review, we aim to outline recent advances in polymeric materials and methodologies for the functional 3D printing technology. The reports are classified based on functionalities, including electronic conductive, thermally conductive, electromagnetic interference shielding, energy storage, and energy harvesting materials. This study attempts to provide a comprehensive overview of the challenges and opportunities for 3D printing functional polymeric materials/devices, also seeks to enlighten the orientation of future research in this field. The idea of harnessing the customization competence of 3D printing technology has recently come under the spotlight, enabling the realization of manifold functional polymeric devices with unprecedented properties to which conventional measures are inaccessible. Recent advances in materials and methodologies to realize functional polymeric devices derived from 3D printing technology are summarized. Specifically, applications categorized according to their specific functionalities are discussed, having areas such as electronic conductive, thermal conductive, electromagnetic interference shielding, energy storage, and energy harvesting applications embodied. In the end, the challenges and opportunities are outlined, which highlights future endeavors that should be directed to this field.

Microbiome-directed therapies are increasingly utilized to optimize thyroid function in both healthy individuals and those with thyroid disorders. However, recent doubts have been raised regarding the efficacy of probiotics, prebiotics, and synbiotics in improving thyroid function. This systematic review aimed to investigate the potential relationship between probiotics/prebiotics and thyroid function by analyzing the impact on thyroid hormone levels. We conducted a comprehensive systematic review and meta-analysis of randomized controlled trials that investigated the effects of probiotics, prebiotics, and synbiotics on free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and thyroid stimulating hormone receptor antibody (TRAb) levels. We searched for articles from PubMed, Scopus, Web of Science, and Embase up until April 1st, 2023, without any language restriction. Quantitative data analysis was performed using a random-effects model, with standardized mean difference (SMD) and 95% confidence interval as summary statistics. The methods and results were reported according to the PRISMA2020 statement. A total of eight articles were included in this review. The meta-analysis showed no significant alterations in TSH (SMD: -0.01, 95% CI: -0.21, 0.20, P = 0.93; I2: 0.00%), fT4 (SMD: 0.04, 95% CI: -0.29, 0.21, P = 0.73; I2: 0.00%) or fT3 (SMD: 0.45, 95% CI: -0.14, 1.03, P = 0.43; I2: 78.00%), while a significant reduction in TRAb levels was observed (SMD: -0.85, 95% CI: -1.54, -0.15, P = 0.02; I2: 18.00%) following probiotics/prebiotics supplementation. No indication of publication bias was found. Probiotics/prebiotics supplementation does not influence thyroid hormone levels, but may modestly reduce TRAb levels in patients with Graves' disease.