scholarly journals Shrub Diversity and Niche Characteristics in the Initial Stage of Reconstruction of Low-Efficiency Cupressus funebris Stands

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1492
Author(s):  
Yang Wang ◽  
Silu Chen ◽  
Wenchun He ◽  
Jingjing Ren ◽  
Xiaochen Wen ◽  
...  

The upper reaches of the Yangtze River are a very important ecological barrier in China, but the ecological benefits of large-scale Cupressus funebris Endl.plantations are low. This study investigated 12 plantations of different compositions and densities, including two densities of Cinnamomum septentrionale Hand.-Mazz. (Cs), Alnus cremastogyne Burk. (Ac), and Toona sinensis (A. Juss.) Roem. (Ts), and mixed plantations of Cs + Ac (CA), Ts + Cs (TC), Ts + Ac (TA), and Ac + Ts + Cs (ATC) and the cutting-blank (CB), and, at the same time, the unreconstructed pure C. funebris (Cf) forest was set as the control. We aimed to explore the influence mechanism of upper tree composition and density on shrub diversity, as well as the relationship between shrub diversity and niche. Our research results are as follows: (1) Among all the patterns, the TA, CA, and TC patterns are the most conducive to improving the diversity of shrubs. The composition and density of different trees have a great influence on the diversity of shrubs. (2) Niche is closely related to the diversity of shrubs. In the patterns of low niche overlap between dominant shrubs, the diversity of shrubs is greater. These results contribute to a deeper understanding of the relationship between the diversity of overstory and shrubs, and reveals the relationship between niche and diversity.

Author(s):  
Liang Sun ◽  
Weikang Tan ◽  
Yanbing Ren ◽  
Xiang Ji ◽  
Zhi Wang ◽  
...  

As the physical environment of urban underground streets space is continuously perfect, people start to anticipate that underground streets with negative impression could satisfy their psychological comfort appeal as traditional ground streets do. Streets’ pavement is of great significance in creating humanized and comfortable underground spatial atmosphere, and different ground pavements of underground commercial streets display different visual comfort effects. We conducted field investigations of a dozen typical underground streets in eight big cities in China with 42 test samples, and this research obtained the pavement elements’ data of underground commercial streets, built virtual 3D scenes based on orthogonal analysis and virtual reality technology of computer vision, acquired the psychological data of spatial experience through virtual reality test, and analyzed the relationship between six elements (glossiness, roughness, color, dimension, pattern, and collage of ground pavement in underground commercial streets) and spatial visual comfort based on quantitative analysis of experimental data. Results show that, “Cold–hot sensation”, “Glossiness”, and “Collage ordered degree” are chief elements for underground commercial streets’ pavement design. The pavement design featured with neutral color, medium- and large-scale and ordered collage form are the design preference and emphasis for underground commercial streets. Neutral color of underground commercial streets pavement may have a great influence on the recognition of pavement glossiness.


VASA ◽  
2020 ◽  
pp. 1-6
Author(s):  
Hanji Zhang ◽  
Dexin Yin ◽  
Yue Zhao ◽  
Yezhou Li ◽  
Dejiang Yao ◽  
...  

Summary: Our meta-analysis focused on the relationship between homocysteine (Hcy) level and the incidence of aneurysms and looked at the relationship between smoking, hypertension and aneurysms. A systematic literature search of Pubmed, Web of Science, and Embase databases (up to March 31, 2020) resulted in the identification of 19 studies, including 2,629 aneurysm patients and 6,497 healthy participants. Combined analysis of the included studies showed that number of smoking, hypertension and hyperhomocysteinemia (HHcy) in aneurysm patients was higher than that in the control groups, and the total plasma Hcy level in aneurysm patients was also higher. These findings suggest that smoking, hypertension and HHcy may be risk factors for the development and progression of aneurysms. Although the heterogeneity of meta-analysis was significant, it was found that the heterogeneity might come from the difference between race and disease species through subgroup analysis. Large-scale randomized controlled studies of single species and single disease species are needed in the future to supplement the accuracy of the results.


2020 ◽  
pp. 27-34
Author(s):  
Vladimir Batiuk

In this article, the ''Cold War'' is understood as a situation where the relationship between the leading States is determined by ideological confrontation and, at the same time, the presence of nuclear weapons precludes the development of this confrontation into a large-scale armed conflict. Such a situation has developed in the years 1945–1989, during the first Cold War. We see that something similar is repeated in our time-with all the new nuances in the ideological struggle and in the nuclear arms race.


2020 ◽  
Author(s):  
Amir Karami ◽  
Brandon Bookstaver ◽  
Melissa Nolan

BACKGROUND The COVID-19 pandemic has impacted nearly all aspects of life and has posed significant threats to international health and the economy. Given the rapidly unfolding nature of the current pandemic, there is an urgent need to streamline literature synthesis of the growing scientific research to elucidate targeted solutions. While traditional systematic literature review studies provide valuable insights, these studies have restrictions, including analyzing a limited number of papers, having various biases, being time-consuming and labor-intensive, focusing on a few topics, incapable of trend analysis, and lack of data-driven tools. OBJECTIVE This study fills the mentioned restrictions in the literature and practice by analyzing two biomedical concepts, clinical manifestations of disease and therapeutic chemical compounds, with text mining methods in a corpus containing COVID-19 research papers and find associations between the two biomedical concepts. METHODS This research has collected papers representing COVID-19 pre-prints and peer-reviewed research published in 2020. We used frequency analysis to find highly frequent manifestations and therapeutic chemicals, representing the importance of the two biomedical concepts. This study also applied topic modeling to find the relationship between the two biomedical concepts. RESULTS We analyzed 9,298 research papers published through May 5, 2020 and found 3,645 disease-related and 2,434 chemical-related articles. The most frequent clinical manifestations of disease terminology included COVID-19, SARS, cancer, pneumonia, fever, and cough. The most frequent chemical-related terminology included Lopinavir, Ritonavir, Oxygen, Chloroquine, Remdesivir, and water. Topic modeling provided 25 categories showing relationships between our two overarching categories. These categories represent statistically significant associations between multiple aspects of each category, some connections of which were novel and not previously identified by the scientific community. CONCLUSIONS Appreciation of this context is vital due to the lack of a systematic large-scale literature review survey and the importance of fast literature review during the current COVID-19 pandemic for developing treatments. This study is beneficial to researchers for obtaining a macro-level picture of literature, to educators for knowing the scope of literature, to journals for exploring most discussed disease symptoms and pharmaceutical targets, and to policymakers and funding agencies for creating scientific strategic plans regarding COVID-19.


2019 ◽  
Vol 22 (3) ◽  
pp. 365-380 ◽  
Author(s):  
Matthias Olthaar ◽  
Wilfred Dolfsma ◽  
Clemens Lutz ◽  
Florian Noseleit

In a competitive business environment at the Bottom of the Pyramid smallholders supplying global value chains may be thought to be at the whims of downstream large-scale players and local market forces, leaving no room for strategic entrepreneurial behavior. In such a context we test the relationship between the use of strategic resources and firm performance. We adopt the Resource Based Theory and show that seemingly homogenous smallholders deploy resources differently and, consequently, some do outperform others. We argue that the ‘resource-based theory’ results in a more fine-grained understanding of smallholder performance than approaches generally applied in agricultural economics. We develop a mixed-method approach that allows one to pinpoint relevant, industry-specific resources, and allows for empirical identification of the relative contribution of each resource to competitive advantage. The results show that proper use of quality labor, storage facilities, time of selling, and availability of animals are key capabilities.


Author(s):  
Richard Culliford ◽  
Alex J. Cornish ◽  
Philip J. Law ◽  
Susan M. Farrington ◽  
Kimmo Palin ◽  
...  

Abstract Background Epidemiological studies of the relationship between gallstone disease and circulating levels of bilirubin with risk of developing colorectal cancer (CRC) have been inconsistent. To address possible confounding and reverse causation, we examine the relationship between these potential risk factors and CRC using Mendelian randomisation (MR). Methods We used two-sample MR to examine the relationship between genetic liability to gallstone disease and circulating levels of bilirubin with CRC in 26,397 patients and 41,481 controls. We calculated the odds ratio per genetically predicted SD unit increase in log bilirubin levels (ORSD) for CRC and tested for a non-zero causal effect of gallstones on CRC. Sensitivity analysis was applied to identify violations of estimator assumptions. Results No association between either gallstone disease (P value = 0.60) or circulating levels of bilirubin (ORSD = 1.00, 95% confidence interval (CI) = 0.96–1.03, P value = 0.90) with CRC was shown. Conclusions Despite the large scale of this study, we found no evidence for a causal relationship between either circulating levels of bilirubin or gallstone disease with risk of developing CRC. While the magnitude of effect suggested by some observational studies can confidently be excluded, we cannot exclude the possibility of smaller effect sizes and non-linear relationships.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Siddharth Arora ◽  
Alexandra Brintrup

AbstractThe relationship between a firm and its supply chain has been well studied, however, the association between the position of firms in complex supply chain networks and their performance has not been adequately investigated. This is primarily due to insufficient availability of empirical data on large-scale networks. To addresses this gap in the literature, we investigate the relationship between embeddedness patterns of individual firms in a supply network and their performance using empirical data from the automotive industry. In this study, we devise three measures that characterize the embeddedness of individual firms in a supply network. These are namely: centrality, tier position, and triads. Our findings caution us that centrality impacts individual performance through a diminishing returns relationship. The second measure, tier position, allows us to investigate the concept of tiers in supply networks because we find that as networks emerge, the boundaries between tiers become unclear. Performance of suppliers degrade as they move away from the focal firm (i.e., Toyota). The final measure, triads, investigates the effect of buying and selling to firms that supply the same customer, portraying the level of competition and cooperation in a supplier’s network. We find that increased coopetition (i.e., cooperative competition) is a performance enhancer, however, excessive complexity resulting from being involved in both upstream and downstream coopetition results in diminishing performance. These original insights help understand the drivers of firm performance from a network perspective and provide a basis for further research.


2021 ◽  
Vol 10 (6) ◽  
pp. 1211
Author(s):  
Li-Te Lin ◽  
Kuan-Hao Tsui

The relationship between serum dehydroepiandrosterone sulphate (DHEA-S) and anti-Mullerian hormone (AMH) levels has not been fully established. Therefore, we performed a large-scale cross-sectional study to investigate the association between serum DHEA-S and AMH levels. The study included a total of 2155 infertile women aged 20 to 46 years who were divided into four quartile groups (Q1 to Q4) based on serum DHEA-S levels. We found that there was a weak positive association between serum DHEA-S and AMH levels in infertile women (r = 0.190, p < 0.001). After adjusting for potential confounders, serum DHEA-S levels positively correlated with serum AMH levels in infertile women (β = 0.103, p < 0.001). Infertile women in the highest DHEA-S quartile category (Q4) showed significantly higher serum AMH levels (p < 0.001) compared with women in the lowest DHEA-S quartile category (Q1). The serum AMH levels significantly increased across increasing DHEA-S quartile categories in infertile women (p = 0.014) using generalized linear models after adjustment for potential confounders. Our data show that serum DHEA-S levels are positively associated with serum AMH levels.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xiang Yin ◽  
Zhiyi Meng ◽  
Xin Yi ◽  
Yong Wang ◽  
Xia Hua

AbstractChina has made great efforts to alleviate poverty in rural ethnic minority areas and targeted achieving the poverty-alleviation task by the end of 2020. Aba, Ganzi, and Liangshan, three of the poorest ethnic prefectures in Sichuan Province, Southwest China, have all implemented “Internet+” tactics since 2013, which have had the positive effect of increasing family revenues by improving communication infrastructure and encouraging the large-scale use of e-commerce. This paper aims to comprehensively investigate whether “Internet+” tactics play a key role in poverty alleviation in Sichuan’s rural ethnic minority areas and to propose further measures to enhance the efficiency of e-commerce practice. To this end, we conduct an analysis using the framework of classic growth theory and use panel data from 2000 to 2018 to examine the relationship between Communication Infrastructure Investment (CII) and a set of poverty-alleviation indicators, including local GDP growth rate (LGGR), local government revenue (LGR), and per-capita income of residents (PCIR). The results indicate that strengthening CII improves the PCIR and local economic growth, playing a key role in poverty alleviation. However, the stimulation of CII on LGGR and LGR wanes as time passes. More financial and technical actions will be needed to improve the efficiency and quality of current strategies for sustainable development in those areas.


Morphology ◽  
2021 ◽  
Author(s):  
Rossella Varvara ◽  
Gabriella Lapesa ◽  
Sebastian Padó

AbstractWe present the results of a large-scale corpus-based comparison of two German event nominalization patterns: deverbal nouns in -ung (e.g., die Evaluierung, ‘the evaluation’) and nominal infinitives (e.g., das Evaluieren, ‘the evaluating’). Among the many available event nominalization patterns for German, we selected these two because they are both highly productive and challenging from the semantic point of view. Both patterns are known to keep a tight relation with the event denoted by the base verb, but with different nuances. Our study targets a better understanding of the differences in their semantic import.The key notion of our comparison is that of semantic transparency, and we propose a usage-based characterization of the relationship between derived nominals and their bases. Using methods from distributional semantics, we bring to bear two concrete measures of transparency which highlight different nuances: the first one, cosine, detects nominalizations which are semantically similar to their bases; the second one, distributional inclusion, detects nominalizations which are used in a subset of the contexts of the base verb. We find that only the inclusion measure helps in characterizing the difference between the two types of nominalizations, in relation with the traditionally considered variable of relative frequency (Hay, 2001). Finally, the distributional analysis allows us to frame our comparison in the broader coordinates of the inflection vs. derivation cline.


Sign in / Sign up

Export Citation Format

Share Document