scholarly journals Predominance of clonal propagation conceals extinction risks of the highly endangered floodplain herb Cnidium dubium

2021 ◽  
Author(s):  
Ilona Leyer ◽  
Birgit Ziegenhagen ◽  
Christina Mengel ◽  
Eva Mosner ◽  
Sascha Liepelt
Keyword(s):  
Gene Flow ◽  
Chloroplast Dna ◽  
Large Scale ◽  
Clonal Propagation ◽  
Conservation Status ◽  
Clonal Diversity ◽  
Small Scale ◽  
Extinction Debt ◽  
River Stretch ◽  
High Level

Habitat loss and degradation due to human-induced landscape alterations are considered to be a major threat to biodiversity. The decline of biodiversity may occur with a time delay leading to a so called extinction debt. Therefore, determining extinction risks and conservation status is not always straightforward. Several life history traits might play a role for the accumulation of an extinction debt. Thus, perennial plant species capable of vegetative propagation might be able to persist temporarily in degraded habitats even though sexual and evolutionary processes are effectively halted. We studied Cnidium dubium, which occurs in scattered patches along river corridors in Central Europe and is critically endangered in Germany. It is a perennial species which is able to propagate clonally. Our aims were to reconstruct demographic processes regarding clonal propagation and gene flow along 400 km of river stretch and with respect to the position in the flooplain, i.e. before or behind dykes. We also wanted to determine whether there is evidence for an extinction debt in C. dubium and to use our insights for conservation recommendations. For this, we used nuclear microsatellites and maternally inherited chloroplast DNA markers and applied a systematic grid based sampling strategy for small scale geographic structures. We observed a high level of clonal propagation. In 935 analysed plants we observed only 121 different genotypes and of 50 studied patches of C. dubium the majority (31 patches) consisted of one single genotype each. Patch size and position were correlated with clonal diversity. Large patches and patches behind dykes exhibited higher clonal diversity. There was no evidence for a large scale genetic substructuring of the study area and no differences in overall genetic diversity between upstream and downstream patches as well as between patches before and behind the dykes. High levels of heterozygosity and a high number of 18 chloroplast DNA haplotypes togetherwith a slightly elevated inbreeding coefficient (Fis) point toward a high level of ancestral polymorphism in an out of equilibrium population due to high levels of clonal propagation and low levels of gene flow and recombination. Therefore, we assume that an extinction debt is present in C. dubium. As a management strategy, we propose to transplant ramets between multiple patches to increase the number of mating partners and therefore restore sexual reproduction.

scholarly journals Design of Compliant Joints for Large Scale Structures

2020 ◽  
Author(s):  
Angela Nastevska ◽  
Jovana Jovanova ◽  
Mary Frecker
Keyword(s):  
Large Scale ◽  
Compliant Mechanisms ◽  
Compliant Mechanism ◽  
Small Scale ◽  
Nonlinear Bending ◽  
Large Scale Structures ◽  
Compliant Joints ◽  
Scale Structures ◽  
High Level ◽  
Novel Design

Abstract Large scale structures can benefit from the design of compliant joints that can provide flexibility and adaptability. A high level of deformation is achieved locally with the design of flexures in compliant mechanisms. Additionally, by introducing contact-aided compliant mechanisms, nonlinear bending stiffness is achieved to make the joints flexible in one direction and stiff in the opposite one. All these concepts have been explored in small scale engineering design, but they have not been applied to large scale structures. In this paper the design of a large scale compliant mechanism is proposed for novel design of a foldable shipping container. The superelasticity of nickel titanium is shown to be beneficial in designing the joints of the compliant mechanism.

scholarly journals Two Decades of Touchable and Walkable Virtual Reality for Blind and Visually Impaired People: A High-Level Taxonomy

2020 ◽  
Vol 4 (4) ◽  
pp. 79
Author(s):  
Julian Kreimeier ◽  
Timo Götzelmann
Keyword(s):  
Virtual Reality ◽  
Virtual Environments ◽  
Visually Impaired ◽  
Large Scale ◽  
Small Scale ◽  
Survey Paper ◽  
Blind And Visually Impaired ◽  
Visually Impaired People ◽  
Impaired People ◽  
High Level

Although most readers associate the term virtual reality (VR) with visually appealing entertainment content, this technology also promises to be helpful to disadvantaged people like blind or visually impaired people. While overcoming physical objects’ and spaces’ limitations, virtual objects and environments that can be spatially explored have a particular benefit. To give readers a complete, clear and concise overview of current and past publications on touchable and walkable audio supplemented VR applications for blind and visually impaired users, this survey paper presents a high-level taxonomy to cluster the work done up to now from the perspective of technology, interaction and application. In this respect, we introduced a classification into small-, medium- and large-scale virtual environments to cluster and characterize related work. Our comprehensive table shows that especially grounded force feedback devices for haptic feedback (‘small scale’) were strongly researched in different applications scenarios and mainly from an exocentric perspective, but there are also increasingly physically (‘medium scale’) or avatar-walkable (‘large scale’) egocentric audio-haptic virtual environments. In this respect, novel and widespread interfaces such as smartphones or nowadays consumer grade VR components represent a promising potential for further improvements. Our survey paper provides a database on related work to foster the creation process of new ideas and approaches for both technical and methodological aspects.

A Perspective on Energy Storage and Other Means to Integrate Increasing Shares of Renewable Electricity Generation

Green ◽  
2014 ◽  
Vol 4 (1-6) ◽  
Author(s):  
Arndt Neuhaus ◽  
Frank-Detlef Drake ◽  
Gunnar Hoffmann ◽  
Friedrich Schulte
Keyword(s):  
Energy Storage ◽  
Power Plants ◽  
Large Scale ◽  
Distributed Storage ◽  
Renewable Energy Sources ◽  
Energy Transition ◽  
System Stability ◽  
Small Scale ◽  
Specific Class ◽  
High Level

AbstractThe transition to a sustainable electricity supply from renewable energy sources (RES) imposes major technical and economic challenges upon market players and the legislator. In particular the rapid growth of volatile wind power and photovoltaic generation requires a high level of flexibility of the entire electricity system, therefore major investments in infrastructures are needed to maintain system stability. This raises the important question about the role that central large-scale energy storage and/or small-scale distributed storage (“energy storage at home”) are going to play in the energy transition. Economic analyses show that the importance of energy storage is going to be rather limited in the medium term. Especially competing options like intelligent grid extension and flexible operation of power plants are expected to remain favourable. Nonetheless additional storage capacities are required if the share of RES substantially exceeds 50% in the long term. Due to the fundamental significance of energy storages, R&D considers a broad variety of types each suitable for a specific class of application.

scholarly journals Upstream to downstream: a multiple-assessment-point approach for targeting non-point-source priority management areas at large watershed scale

2013 ◽  
Vol 10 (11) ◽  
pp. 14535-14555
Author(s):  
L. Chen ◽  
Y. Zhong ◽  
G. Wei ◽  
Z. Shen
Keyword(s):  
Point Source ◽  
Large Scale ◽  
Cost Effective ◽  
Small Scale ◽  
Watershed Scale ◽  
Nps Pollution ◽  
Specific Assessment ◽  
High Level ◽  
Multiple Assessment

Abstract. The identification of priority management areas (PMAs) is essential for the control of non-point source (NPS) pollution, especially for a large-scale watershed. However, previous studies have typically focused on small-scale catchments adjacent to specific assessment points; thus, the interactions between multiple river points remain poorly understood. In this study, a multiple-assessment-point PMA (MAP-PMA) framework was proposed by integrating the upstream sources and the downstream transport aspects of NPS pollution. Based on the results, the integration of the upstream input changes was vital for the final PMAs map, especially for downstream areas. Contrary to conventional wisdom, this research recommended that the NPS pollutants could be best controlled among the upstream high-level PMAs when protecting the water quality of the entire watershed. The MAP-PMA framework provided a more cost-effective tool for the establishment of conservation practices, especially for a large-scale watershed.

scholarly journals Vitrification of High-Level Radioactive Waste in a Small-Scale Joule-Heated Ceramic Melter

1981 ◽  
Vol 6 ◽  
Author(s):  
Gerald B. Woolsey ◽  
M. John Plodinec
Keyword(s):  
Radioactive Waste ◽  
Large Scale ◽  
Liquid Waste ◽  
Glass Frit ◽  
Small Scale ◽  
Savannah River ◽  
Savannah River Plant ◽  
Reference Process ◽  
High Level ◽  
Large Scale Tests

ABSTRACTVitrification is the reference process for the immobilization of radioactive waste from the production of defense materials at the Savannah River Plant (SRP). Since 1979, a small vitrification facility (1 Ib/hr) has been operated at the Savannah River Laboratory using actual SRP waste. In previous studies. dried waste was fed to this smaller melter. This report discusses direct feeding of actual liquid-waste slurries to the small melter. These liquidfeeding tests demonstrated that addition of premelted glass frit to the waste slurry reduces the amount of material volatilized. Results of these tests are in accord with results of large-scale tests with actual waste.

scholarly journals PROTOTIPE INSTALASI PENGOLAHAN AIR LIMBAH INDUSTRI PENGOLAHAN IKAN DI KECAMATAN MUNCAR, KABUPATEN BANYUWANGI

2016 ◽  
Vol 11 (1) ◽  
pp. 7
Author(s):  
Setiyono . ◽  
Satmoko Yudo
Keyword(s):  
Waste Water ◽  
Large Scale ◽  
Negative Impact ◽  
Liquid Waste ◽  
Small Scale ◽  
Fish Processing ◽  
Industry Growth ◽  
Processing Industry ◽  
Industry Waste ◽  
High Level

Muncar region known as the area of the fish and the fish processing industry. Many of the fish processing industries in large scale, small scale and household at this time growing so rapidly. With the rapid growth of the fish processing industry in the Muncar city has provided a very significant impact on the city growth, which eventually brought the various impacts, whether they are positive or negative. One of the negative impact of processing industry growth in Muncar is environmental of pollution is the discharge of liquid waste from industrial fish-processing industry. Low level of understanding IPAL waste management system and cause difficulties to manage the waste, therefore almostall waste that generated in the region immediately removed to the public channels. Waste disposal without treatment is causing high level of environmental pollution in the vicinity of the location of industry. One effort to solve the problem of waste-processing technology is determine processingof waste water and fish processing, it has been done to test prototype installation processing waste water in one of the fish processing industry in the Muncar District. Key words : fish processing industry waste water, environmetal pollution, waste water processing prototype.

Isolation of genomic clones containing the amdS gene of Aspergillus nidulans and their use in the analysis of structural and regulatory mutations

1983 ◽  
Vol 3 (8) ◽  
pp. 1430-1439 ◽  
Author(s):  
M J Hynes ◽  
C M Corrick ◽  
J A King
Keyword(s):  
Aspergillus Nidulans ◽  
Large Scale ◽  
Small Scale ◽  
Cis Acting ◽  
Physical Maps ◽  
Regulatory Circuits ◽  
Regulatory Mutations ◽  
Amds Gene ◽  
Chromosome Iii ◽  
High Level

Previous analysis of the amdS gene of Aspergillus nidulans has identified multiple regulatory circuits mediated by trans-acting regulatory genes, cis-acting mutations have been identified and shown to specifically affect individual regulatory circuits. Fine-structure genetic mapping of the amdS regions showed that these cis-acting mutations occur in a complex controlling region adjacent to the amdS structural gene. The amdS gene was cloned by differential hybridization, using cDNA probes derived from a high-level-producing strain and from a strain with a large amdS deletion mutation. RNA blotting experiments showed that a single RNA species of 1,600 to 1,700 base pairs is transcribed from the amdS gene. DNA blotting experiments on a large number of amdS mutant strains, including deletions and translocations, allowed the genetic and physical maps of the gene to be correlated. The controlling region of the gene is situated at the 5' end of the gene and the direction of transcription is toward the centromere of chromosome III. The regulatory mutations in the controlling region were found to be due to small-scale alterations in the DNA rather than to large-scale rearrangements resulting in gene fusions.

scholarly journals Upstream to downstream: a multiple-assessment-point approach for targeting non-point-source priority management areas at large watershed scale

2014 ◽  
Vol 18 (4) ◽  
pp. 1265-1272 ◽  
Author(s):  
L. Chen ◽  
Y. Zhong ◽  
G. Wei ◽  
Z. Shen
Keyword(s):  
Point Source ◽  
Large Scale ◽  
Cost Effective ◽  
Small Scale ◽  
Nps Pollution ◽  
Specific Assessment ◽  
High Level ◽  
Multiple Assessment

Abstract. The identification of priority management areas (PMAs) is essential for the control of non-point-source (NPS) pollution, especially for a large-scale watershed. However, previous studies have typically focused on small-scale catchments adjacent to specific assessment points; thus, the interactions between multiple river points remain poorly understood. In this study, a multiple-assessment-point PMA (MAP-PMA) framework was proposed by integrating the upstream sources and the downstream transport aspects of NPS pollution. Daning River watershed was taken as a case study in this paper, which has demonstrated that the integration of the upstream input changes was vital for the final PMAs map, especially for downstream areas. Contrary to conventional wisdom, this research recommended that the NPS pollutants could be best controlled among the upstream high-level PMAs when protecting the water quality of the entire watershed. The MAP-PMA framework provided a more cost-effective tool for the establishment of conservation practices, especially for a large-scale watershed.

scholarly journals μDFL: A Secure Microchained Decentralized Federated Learning Fabric atop IoT Networks

2021 ◽  
Author(s):  
Ronghua Xu ◽  
Yu Chen
Keyword(s):  
Large Scale ◽  
Privacy Preservation ◽  
Security And Privacy ◽  
Small Scale ◽  
Proof Of Concept ◽  
Byzantine Fault Tolerance ◽  
Consensus Protocol ◽  
High Level ◽  
Collaborative Training ◽  
And Storage

<div>Federated Learning (FL) has been recognized as a privacy-preserving machine learning (ML) technology that enables collaborative training and learning of a global ML model based on the aggregation of distributed local model updates. However, security and privacy guarantees could be compromised due to malicious participants and the centralized aggregation manner. Possessing attractive features like decentralization, immutability and auditability, Blockchain is promising to enable a tamper-proof and trust-free framework to enhance performance and security in IoT based FL systems. However, directly integrating blockchains into the large scale IoT-based FL scenarios still faces many limitations, such as high computation and storage demands, low transactions throughput, poor scalability and challenges in privacy preservation. This paper proposes uDFL, a novel hierarchical IoT network fabric for decentralized federated learning (DFL) atop of a lightweight blockchain called microchain. Following the hierarchical infrastructure of FL, participants in uDFL are fragmented into multiple small scale microchains. Each microchain network relies on a hybrid Proof of Credit (PoC) block generation and Voting-based Chain Finality (VCF) consensus protocol to ensure efficiency and privacy-preservation at the network of edge. Meanwhile, microchains are federated vie a high-level inter-chain network, which adopts an efficient Byzantine Fault Tolerance (BFT) consensus protocol to achieve scalability and security.</div><div>A proof-of-concept prototype is implemented, and the experimental results verify the feasibility of the proposed uDFL solution in cross-devices FL settings with efficiency, security and privacy guarantees.</div>

Cold Crucible Inductive Melting Technology – Application to Vitrification and Ceramization of High Level and Actinide Wastes

2010 ◽  
Vol 73 ◽  
pp. 183-193 ◽  
Author(s):  
Sergey V. Stefanovsky ◽  
Vladimir V. Lebedev ◽  
Alexander G. Ptashkin ◽  
Sergey A. Dmitriev ◽  
James C. Marra
Keyword(s):  
Large Scale ◽  
Fuel Cycle ◽  
Iron Phosphate ◽  
External Source ◽  
High Level Waste ◽  
Small Scale ◽  
Cold Crucible ◽  
Technology Application ◽  
High Iron ◽  
High Level

Cold crucible inductive melting is a promising method for production of high-temperature materials. The method is based on direct heating of conductive materials by high-frequency (105-107 Hz) electromagnetic field from an external source. Application of the CCIM to production of vitreous borosilicate and alumino/iron phosphate and ceramic waste forms such as Synroc and its varieties and pyrochlore, murataite and garnet-based ceramics has been successfully demonstrated. Currently a full-scale low level waste vitrification plant based on a 418 mm inner diameter cold crucibles energized from a 1.76MHz/160 kW generators is under operation at SIA Radon. This plant was used for demonstration of feasibility of cold crucible vitrification of Savannah River Site high-iron and high iron/aluminum high level wastes. Numerous ceramic and glass ceramic materials containing high level and actinide waste surrogates such as actinide and actinide/rare earth fractions of high level waste have been successfully produced in the Radon lab- and bench-scale cold crucible based units operated at 5.28 and 1.76 MHz. Large-scale cold crucibles may be applied for vitrification of liquid and solid low and high level wastes whereas small-scale cold crucible may be efficiently used for immobilization of actinide-bearing waste generated from advanced nuclear fuel cycle reprocessing.

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