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Published: 28 May 2020
by MDPI
Agronomy, Volume 10; doi:10.3390/agronomy10060767

Abstract:
Land-use changes and especially management intensification currently pose a major threat to biodiversity both on and beneath the soil surface. With a comparative approach, we investigated how management intensity in orchards and meadows influences soil macro-invertebrate communities in a North-Italian Alpine region. We compared soil fauna assemblies from traditional low-input sites with respective intensively managed ones. As expected, the taxonomical richness and diversity were lower in both intensive management types. Extensive management of both types revealed similar communities, while intensification led to substantial differences between management types. From these results, we conclude that intensification of agricultural practices severely alters the soil fauna community and biodiversity in general, however, the direction of these changes is governed by the management type. In our view, extensive management, traditional for mountain areas, favors soil fauna communities that have adapted over a long time and can thus be viewed as a sustainable reference condition for new production systems that consider the protection of soil diversity in order to conserve essential ecosystem functions.
Published: 28 May 2020
by MDPI
Agronomy, Volume 10; doi:10.3390/agronomy10060768

Abstract:
The introduction of nitrogen fixing bacteria (NFB) and arbuscular mycorrhizal fungi (AMF) into the soil is an advisable agricultural practice for the crop, since it enhances nutrient and water uptake and tolerance to biotic and abiotic stresses. The aim of this work was to study plant nutrition, biological nitrogen fixation (BNF) and crop yield and quality, after inoculating seeds with NFBs ((Rhizobium leguminosarum, Burkholderia cenocepacia, Burkholderia vietnamiensis)) and/or AMFs (Rhizophagus irregularis, Claroideoglomus etunicatum, Claroideoglomus claroideum and Funneliformis mosseae) in a fava bean crop in two seasons. The composition of the nodule bacterial community was evaluated by the high-throughput sequencing analysis of bacterial 16 S rRNA genes. It was found that microbial inoculation accompanied by a 20% decrease in mineral fertilization had no significant effect on crop yield or the nutritional characteristics compared with a non-inoculated crop, except for an increase in the grain protein content in inoculated plants. None of the inoculation treatments increased biological nitrogen fixation over a non-inoculated level. The bacterial rRNA analysis demonstrated that the genus Rhizobium predominated in all nodules, both in inoculated and non-inoculated treatments, suggesting the previous presence of these bacteria in the soil. In our study, inoculation with Rhizobium leguminosarum was the most effective treatment for increasing protein content in seeds, while Burkholderia sp. was not able to colonise the plant nodules. Inoculation techniques used in fava beans can be considered an environmentally friendly alternative, reducing the input of fertilizers, while maintaining crop yield and quality, with the additional benefit of increasing the grain protein content. However, further research is required on the selection and detection of efficient rhizobial strains under local field conditions, above all those related to pH and soil type, in order to achieve superior nitrogen-fixing bacteria.
Published: 28 May 2020
by MDPI
Applied Sciences, Volume 10; doi:10.3390/app10113727

Abstract:
Markov queueing models are a powerful tool to evaluate the performance of computer networks and have been used in telecommunication studies for over 100 years. To apply them to the evaluation of the modern Internet, we should not only adapt them to the contemporary network structures but also include a description of the complex stochastic patterns (self-similarity and long-range dependance) of transmitted flows. We examine the features of two Markov models of an almost self-similar process, keeping in mind the modeling of Internet traffic. We have found that the obtained results are comparable with those achieved using a well-known generator of self-similar traffic.
Published: 28 May 2020
by MDPI
Antibiotics, Volume 9; doi:10.3390/antibiotics9060289

Abstract:
Bak-ri-hyang (Thymus quinquecostatus Celak.) is an important medicinal and aromatic plant in Korea. T. quinquecostatus population and is always mixed with other thyme cultivars during cultivation and marketing. Hence, this study aimed to determine the genetic variability and the essential oil composition of three Korean native thyme, T. quinquecostatus cultivars collected from the Wolchul, Jiri, and Odae mountains, in comparison with six commercial thyme cultivars (T. vulgaris), to distinguish Bak-ri-hyang from other thyme cultivars. The composition of essential oils obtained from nine individuals was analyzed by gas chromatography–mass spectrometry (GC–MS). The random amplified polymorphic DNA (RAPD) analysis was accomplished using 16 different primers. The GC–MS analysis revealed that Wolchul, creeping, golden, and orange cultivars belong to the geraniol chemotype. Whereas the Odae, lemon, and silver cultivars belong to the thymol chemotype. Further, linalool was the most abundant component in carpet and Jiri cultivars. The RAPD analysis demonstrated that all thyme cultivars showed characteristic RAPD patterns that allowed their identification. In total, 133 bands were obtained using 16 primers, and 124 bands were polymorphic, corresponding to 93.2% polymorphism. Cluster analysis of RAPD markers established the presence of clear separation from nine thyme cultivars. The highest dissimilarity and similarity coefficient of the RAPD markers were 0.58 and 0.98, respectively. According to the RAPD patterns, the nine thyme cultivars could be divided into two major clusters. Among three Korean cultivars, the Wolchul and Odae cultivars were placed into the same cluster, but they did not show identical clustering with their essential oil compositions. The findings of the present study suggest that RAPD analysis can be a useful tool for marker-assisted identification of T. quinquecostatus from other Thymus species.
Published: 28 May 2020
by MDPI
Materials, Volume 13; doi:10.3390/ma13112450

Abstract:
A comparison of the influence of sepiolite and lignin as potential synergists for fire retardant (FR) systems based on ammonium polyphosphate (APP) has been carried out in polyurethane elastomer and polylactide. Different ratios of kraft lignin and sepiolite were tested in combination with APP in both polymers. The thermal stability and the fire behavior of the corresponding composites were evaluated using Thermogravimetric Analysis (TGA), a Pyrolysis Combustion Flow Calorimeter (PCFC) and Cone Calorimeter (CC). The mechanisms of flame retardancy imparted by APP and other components were investigated. Synergistic effects were highlighted but only for specific ratios between APP and sepiolite in polyurethane elastomer (PUE) and polylactide (PLA) on one hand, and between APP and lignin in PLA on the other hand. Sepiolite acts as char reinforcement but through the formation of new phosphorus compounds it is also able to form a protective layer. Conversely, only complementary effects on fire performance were noted for lignin in PUE due to a dramatic influence on thermal stability despite its action on char formation.
Correction
Masayuki Tera, Sciprofile linkTomotsugu Koyama, Sciprofile linkJun Murata, Ayako Furukawa, Shoko Mori, Toshiaki Azuma, Takehiro Watanabe, Sciprofile linkKatsuhito Hori, Atsushi Okazawa, Yasuaki Kabe, et al.
Scientific Reports, Volume 10, pp 1-2; doi:10.1038/s41598-020-66086-7

Abstract:
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Alain Morau, Hans-Peter Piepho
Chemical and Biological Technologies in Agriculture, Volume 7, pp 1-13; doi:10.1186/s40538-020-0176-x

Abstract:
The use of biostimulants like humic substances is a promising innovative approach in agriculture to activate and sustain physiological plant processes. The development of specific bioassays is required to study their bioactivity in laboratory conditions. In previous investigations, a soil-less bioassay with cress seedlings (Lepidium sativum L.) was developed for a biostimulant used in the biodynamic agriculture, the horn-manure preparation (HMP), a fermented cow manure sprayed at low concentrations onto fields. Objectives of the present study were to refine the bioassay by investigating the interactions between the HMP bioactivity and the test factors (i) water volume, (ii) gravistimulation, and (iii) exposure to fluorescent light. The interactions between the test factors and the HMP treatment were significant in all series (p < 0.05, Wald F-test). Water overdose and gravitropic stress reduced root growth (down to − 24.2% and − 19.9%, respectively, p < 0.0001, Tukey–Kramer test). The HMP treatment partly compensated these effects by enhancing root growth by (i) water overdose (up to + 4.3%, p = 0.048, n = 4), and (ii) gravitropic stress (up to + 9.5%, p = 0.0004, n = 8). (iii) Furthermore, under the combined stress factors, fluorescent light exposure enhanced the HMP enhancing effect (up to + 12.3%, p = 0.007, n = 6). The HMP bioactivity appeared to consist of a compensatory mode of action regarding the stress factors water overdose and gravistimulation, and a synergetic interaction with fluorescent light exposure. The HMP seems to interact with the plant sensory systems, likely stimulating the plant’s adaptability to its environment by increasing self-regulating processes. The bioassay sensitivity was successfully increased by integrating these interactions in the experimental set-up and adjusting the growth environment. This approach can be used to adjust the bioassay to other biostimulants.
Simin Xia, Xi Chen
Cell Discovery, Volume 6, pp 1-4; doi:10.1038/s41421-020-0175-x

Abstract:
Wang, C., Horby, P. W., Hayden, F. G. & Gao, G. F. A novel coronavirus outbreak of global health concern. Lancet 395, 496–496 (2020). Zhang, Y.-Z. Novel 2019 coronavirus genome. Virological. Org. Available from: http://virological.org/t/novel-2019-coronavirus-genome/319 (2020). Corman, V. M. et al. Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR. Eurosurveillance 25, 23–30 (2020). Chu, D. K. W. et al. Molecular diagnosis of a novel coronavirus (2019-nCoV) causing an outbreak of pneumonia. Clin. Chem. 4, 549–555 (2020). Huang, C., Wang, Y. & Li, X. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet 395, 496–496 (2020). Li, Q. et al. Early transmission dynamics in wuhan, China, of novel coronavirus-infected pneumonia. N. Engl. J. Med. 382, 1199–1207 (2020). Balmaseda, A. et al. Antibody-based assay discriminates Zika virus infection from other flaviviruses. Proc. Natl. Acad. Sci. USA 114, 8384–8389 (2017). Myhrvold, C. et al. Field-deployable viral diagnostics using CRISPR-Cas13. Science 360, 444–448 (2018). Piepenburg, O., Williams, C. H., Stemple, D. L. & Armes, N. A. DNA detection using recombination proteins. PLoS Biol. 4, 1115–1121 (2006). Zhao, Y. X., Chen, F., Li, Q., Wang, L. H. & Fan, C. H. Isothermal amplification of nucleic acids. Chem. Rev. 115, 12491–12545 (2015). Daher, R. K., Stewart, G., Boissinot, M. & Bergeron, M. G. Recombinase polymerase amplification for diagnostic applications. Clin. Chem. 62, 947–958 (2016). Obande, G. A. & Singh, K. K. B. Current and future perspectives on isothermal nucleic acid amplification technologies for diagnosing infections. Infect. Drug Resist. 13, 455–483 (2020). Download references We thank the core facilities at The HIT Center for Life Sciences of Harbin Institute of Technology (HIT) and the startup grant from HIT. X.C. conceived and designed the experiments; S.X. and X.C. participated in multiple experiments and analyzed the data; X.C. wrote the manuscript. Correspondence to Xi Chen. The authors declare that they have no conflict of interest. Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Reprints and Permissions Xia, S., Chen, X. Single-copy sensitive, field-deployable, and simultaneous dual-gene detection of SARS-CoV-2 RNA via modified RT–RPA. Cell Discov 6, 37 (2020). https://doi.org/10.1038/s41421-020-0175-x Download citation Received: 01 April 2020 Accepted: 05 May 2020 Published: 28 May 2020 DOI: https://doi.org/10.1038/s41421-020-0175-x
Ірина Гарбера, Донецький Національний Університет Імені Василя Стуса
Репрезентація освітніх досягнень, мас-медіа та роль філології у сучасній системі наук (1st. ed); doi:10.36074/rodmmrfssn.ed-1.01

Abstract:
У роботі розглянуто поняття концепту як лінгвокультурного утворення, акцентовано на тісних зв’язках лінгвокультурного концепту та певного соціуму, з його унікальними світобаченням, духовними цінностями, культурою, мовою. Зазначено, що, з огляду на антропоцентричність сучасних лінгвістичних дисциплін, найбільш актуальним постає студіювання лінгвокультурного концепту людина. Основні поняттєві параметри й ознаки концепту людина виокремлено методом аналізу однойменних лексикографічних дефініцій – з тлумачного, філософського, психологічного, асоціативного, соціологічного, символьного, культурологічного словників. Зазначений концепт кваліфікує людину як природно-соціальну істоту, що має свідомість і мову, здатна мислити, продуктивно працювати, еволюціонувати, створюючи власну історію та національну культуру.
Maria De Lourdes Pinto De Almeida, Sciprofile linkJosé Camilo Dos Santos Filho
Revista Internacional de Educação Superior, Volume 6; doi:10.20396/riesup.v6i0.8659498

Abstract:
É com imenso prazer que apresentamos o volume 06 (seis) da nossa Revista Internacional de Educação - RIESup, ano de 2020. Temos 24 (vinte e quatro) artigos, 03 (três) resenhas, 13 (treze) relatos de pesquisa e 05 (cinco) relatos de experiência.
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