Genotype- and Cell-Specific Dynamics of Tandem Repeat Patterns in Aegilops speltoides Tausch (Poaceae, Triticeae)

2017 ◽  
Vol 153 (2) ◽  
pp. 105-116 ◽  
Author(s):  
Olga Raskina
Keyword(s):  
Repetitive Dna ◽  
Tandem Repeat ◽  
Structural Integrity ◽  
Wide Spectrum ◽  
Chromosomal Rearrangements ◽  
Wild Plant ◽  
Aegilops Speltoides ◽  
Nonhomologous Recombination ◽  
In The Wild ◽  
The Impact

In wild plant populations, chromosome rearrangements lead to the wide intraspecific polymorphisms in the abundance and patterns of highly repetitive DNA. However, despite the large amount of accumulated data, the impact of the complex repetitive DNA fraction on genome reorganization and functioning and the mechanisms balancing and maintaining the structural integrity of the genome are not fully understood. Homologous recombination is thought to play a key role in both genome reshuffling and stabilization, while the contribution of nonhomologous recombination seems to be undervalued. Here, tandem repeat patterns and dynamics during pollen mother cell development were addressed, with a focus on the meiotic recombination that determines chromosome/genome repatterning and stabilization under cross-pollination and artificial hybridization in wild goatgrass, Aegilops speltoides. Native plants from contrasting allopatric populations and artificially created intraspecific hybrids were investigated using a FISH approach. Cytogenetic analysis uncovered a wide spectrum of genotype- and cell-specific chromosomal rearrangements, suggesting intensive repatterning of both parental and hybrid genomes. The data obtained provide evidence that repetitive elements serve as overabundant and ubiquitous resources for maintaining chromosome architecture/genome integrity through homologous and nonhomologous recombination at the intraorganismal level, and genotype-specific repatterning underlies intrapopulation polymorphisms and intraspecific diversification in the wild.

scholarly journals Potential and limitations of finite element modelling in assessing structural integrity of coralline algae under future global change

2015 ◽  
Vol 12 (19) ◽  
pp. 5871-5883 ◽  
Author(s):  
L. A. Melbourne ◽  
J. Griffin ◽  
D. N. Schmidt ◽  
E. J. Rayfield
Keyword(s):  
Climate Change ◽  
Finite Element ◽  
Structural Integrity ◽  
Geometric Model ◽  
Algal Growth ◽  
Coralline Algae ◽  
Rocky Shores ◽  
Element Analysis ◽  
Scan Data ◽  
The Impact

Abstract. Coralline algae are important habitat formers found on all rocky shores. While the impact of future ocean acidification on the physiological performance of the species has been well studied, little research has focused on potential changes in structural integrity in response to climate change. A previous study using 2-D Finite Element Analysis (FEA) suggested increased vulnerability to fracture (by wave action or boring) in algae grown under high CO2 conditions. To assess how realistically 2-D simplified models represent structural performance, a series of increasingly biologically accurate 3-D FE models that represent different aspects of coralline algal growth were developed. Simplified geometric 3-D models of the genus Lithothamnion were compared to models created from computed tomography (CT) scan data of the same genus. The biologically accurate model and the simplified geometric model representing individual cells had similar average stresses and stress distributions, emphasising the importance of the cell walls in dissipating the stress throughout the structure. In contrast models without the accurate representation of the cell geometry resulted in larger stress and strain results. Our more complex 3-D model reiterated the potential of climate change to diminish the structural integrity of the organism. This suggests that under future environmental conditions the weakening of the coralline algal skeleton along with increased external pressures (wave and bioerosion) may negatively influence the ability for coralline algae to maintain a habitat able to sustain high levels of biodiversity.

scholarly journals A Survey of Electromagnetic Influence on UAVs from an EHV Power Converter Stations and Possible Countermeasures

Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 701
Author(s):  
Yanchu Li ◽  
Qingqing Ding ◽  
Keyue Li ◽  
Stanimir Valtchev ◽  
Shufang Li ◽  
...  
Keyword(s):  
Electromagnetic Interference ◽  
Wide Spectrum ◽  
Electromagnetic Emission ◽  
Power Converter ◽  
Electromagnetic Environment ◽  
Communication Circuits ◽  
Electromagnetic Emissions ◽  
Surrounding Space ◽  
Extra High Voltage ◽  
The Impact

It is inevitable that high-intensity, wide-spectrum electromagnetic emissions are generated by the power electronic equipment of the Extra High Voltage (EHV) power converter station. The surveillance flight of Unmanned Aerial Vehicles (UAVs) is thus, situated in a complex electromagnetic environment. The ubiquitous electromagnetic interference demands higher electromagnetic protection requirements from the UAV construction and operation. This article is related to the UAVs patrol inspections of the power line in the vicinity of the EHV converter station. The article analyzes the electromagnetic interference characteristics of the converter station equipment in the surrounding space and the impact of the electromagnetic emission on the communication circuits of the UAV. The anti-electromagnetic interference countermeasures strive to eliminate or reduce the threats of electromagnetic emissions on the UAV’s hardware and its communication network.

scholarly journals Involvement of Very Short DNA Tandem Repeats and the Influence of the RAD52 Gene on the Occurrence of Deletions in Saccharomyces cerevisiae

Genetics ◽  
2000 ◽  
Vol 156 (2) ◽  
pp. 549-557 ◽  
Author(s):  
Anne J Welcker ◽  
Jacky de Montigny ◽  
Serge Potier ◽  
Jean-Luc Souciet
Keyword(s):  
Fusion Proteins ◽  
Tandem Repeats ◽  
Chromosomal Rearrangements ◽  
Reversion Rate ◽  
Wild Type ◽  
Recombination Mechanism ◽  
Nonhomologous Recombination ◽  
Deletion Rate ◽  
Dna Tandem Repeats

Abstract Chromosomal rearrangements, such as deletions, duplications, or Ty transposition, are rare events. We devised a method to select for such events as Ura+ revertants of a particular ura2 mutant. Among 133 Ura+ revertants, 14 were identified as the result of a deletion in URA2. Of seven classes of deletions, six had very short regions of identity at their junctions (from 7 to 13 bp long). This strongly suggests a nonhomologous recombination mechanism for the formation of these deletions. The total Ura+ reversion rate was increased 4.2-fold in a rad52Δ strain compared to the wild type, and the deletion rate was significantly increased. All the deletions selected in the rad52Δ context had microhomologies at their junctions. We propose two mechanisms to explain the occurrence of these deletions and discuss the role of microhomology stretches in the formation of fusion proteins.

scholarly journals The Impact of Fluid Loss and Carbohydrate Consumption during Exercise, on Young Cyclists’ Fatigue Perception in Relation to Training Load Level

2021 ◽  
Vol 18 (6) ◽  
pp. 3282
Author(s):  
Leonardo Cesanelli ◽  
Berta Ylaitė ◽  
Giuseppe Messina ◽  
Daniele Zangla ◽  
Stefania Cataldi ◽  
...  
Keyword(s):  
Perceived Exertion ◽  
Wide Spectrum ◽  
Load Level ◽  
Training Load ◽  
Fluid Loss ◽  
Young Athletes ◽  
Carbohydrate Consumption ◽  
Significant Difference ◽  
Training Impulse ◽  
The Impact

High-level young athletes need to face a wide spectrum of stressors on their journey to élite categories. The aims of the present study are (i) to evaluate session rate of perceived exertion (sRPE) at different training impulse (TRIMP) categories and the correlations between these two variables and, (ii) evaluate the correlations between sRPE, fluid loss, and carbohydrate consumption during exercise. Data on Edward’s TRIMP, sRPE, body mass loss pre- and post- exercise (∆), and carbohydrate consumption (CHO/h) during exercise have been acquired from eight male junior cyclists during a competitive season. One-way ANOVA and correlation analysis with linear regression have been performed on acquired data. sRPE resulted in a significant difference in the three TRIMP categories (p < 0.001). sRPE resulted in being very largely positively associated with TRIMP values (p < 0.001; R = 0.71). ∆ as well as CHO/h was largely negatively related with sRPE in all TRIMP categories (p < 0.001). The results confirmed the role of fluid balance and carbohydrate consumption on the perception of fatigue and fatigue accumulation dynamics independently from the training load. Young athletes’ training load monitoring and nutritional-hydration support represent important aspects in athlete’s exercise-induced fatigue management.

scholarly journals The environmental and ecological determinants of elevated Ross River Virus exposure in koalas residing in urban coastal landscapes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Brian J. Johnson ◽  
Amy Robbins ◽  
Narayan Gyawali ◽  
Oselyne Ong ◽  
Joanne Loader ◽  
...  
Keyword(s):  
Animal Movement ◽  
Ross River Virus ◽  
Mosquito Vector ◽  
Large Numbers ◽  
Culex Annulirostris ◽  
Coastal Landscapes ◽  
In The Wild ◽  
Virus Exposure ◽  
Elevated Exposure ◽  
The Impact

AbstractKoala populations in many areas of Australia have declined sharply in response to habitat loss, disease and the effects of climate change. Koalas may face further morbidity from endemic mosquito-borne viruses, but the impact of such viruses is currently unknown. Few seroprevalence studies in the wild exist and little is known of the determinants of exposure. Here, we exploited a large, spatially and temporally explicit koala survey to define the intensity of Ross River Virus (RRV) exposure in koalas residing in urban coastal environments in southeast Queensland, Australia. We demonstrate that RRV exposure in koalas is much higher (> 80%) than reported in other sero-surveys and that exposure is uniform across the urban coastal landscape. Uniformity in exposure is related to the presence of the major RRV mosquito vector, Culex annulirostris, and similarities in animal movement, tree use, and age-dependent increases in exposure risk. Elevated exposure ultimately appears to result from the confinement of remaining coastal koala habitat to the edges of permanent wetlands unsuitable for urban development and which produce large numbers of competent mosquito vectors. The results further illustrate that koalas and other RRV-susceptible vertebrates may serve as useful sentinels of human urban exposure in endemic areas.

scholarly journals Codon harmonization reduces amino acid misincorporation in bacterially expressed P. falciparum proteins and improves their immunogenicity

AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Neeraja Punde ◽  
Jennifer Kooken ◽  
Dagmar Leary ◽  
Patricia M. Legler ◽  
Evelina Angov
Keyword(s):  
Protein Structure ◽  
Amino Acid ◽  
Codon Usage ◽  
Dna Sequences ◽  
Structural Integrity ◽  
Host Cells ◽  
Loss Of Function ◽  
Species Specific ◽  
And Function ◽  
The Impact

Abstract Codon usage frequency influences protein structure and function. The frequency with which codons are used potentially impacts primary, secondary and tertiary protein structure. Poor expression, loss of function, insolubility, or truncation can result from species-specific differences in codon usage. “Codon harmonization” more closely aligns native codon usage frequencies with those of the expression host particularly within putative inter-domain segments where slower rates of translation may play a role in protein folding. Heterologous expression of Plasmodium falciparum genes in Escherichia coli has been a challenge due to their AT-rich codon bias and the highly repetitive DNA sequences. Here, codon harmonization was applied to the malarial antigen, CelTOS (Cell-traversal protein for ookinetes and sporozoites). CelTOS is a highly conserved P. falciparum protein involved in cellular traversal through mosquito and vertebrate host cells. It reversibly refolds after thermal denaturation making it a desirable malarial vaccine candidate. Protein expressed in E. coli from a codon harmonized sequence of P. falciparum CelTOS (CH-PfCelTOS) was compared with protein expressed from the native codon sequence (N-PfCelTOS) to assess the impact of codon usage on protein expression levels, solubility, yield, stability, structural integrity, recognition with CelTOS-specific mAbs and immunogenicity in mice. While the translated proteins were expected to be identical, the translated products produced from the codon-harmonized sequence differed in helical content and showed a smaller distribution of polypeptides in mass spectra indicating lower heterogeneity of the codon harmonized version and fewer amino acid misincorporations. Substitutions of hydrophobic-to-hydrophobic amino acid were observed more commonly than any other. CH-PfCelTOS induced significantly higher antibody levels compared with N-PfCelTOS; however, no significant differences in either IFN-γ or IL-4 cellular responses were detected between the two antigens.

scholarly journals Effect of Lipopolysaccharides (LPS) and Lipoteichoic acid (LTA) on the Inflammatory Response in Rumen Epithelial Cells (REC) and the Impact of LPS on Claw Explants

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 2058
Author(s):  
Nicole Reisinger ◽  
Dominik Wendner ◽  
Nora Schauerhuber ◽  
Elisabeth Mayer
Keyword(s):  
Epithelial Cells ◽  
Inflammatory Response ◽  
Structural Integrity ◽  
Animal Health ◽  
Lipoteichoic Acid ◽  
Local Inflammatory Response ◽  
Tissue Integrity ◽  
Separation Force ◽  
The Impact ◽  
Rumen Epithelial Cells

Endotoxins play a crucial role in ruminant health due to their deleterious effects on animal health. The study aimed to evaluate whether LPS and LTA can induce an inflammatory response in rumen epithelial cells. For this purpose, epithelial cells isolated from rumen tissue (RECs) were stimulated with LPS and LTA for 1, 2, 4, and 24 h. Thereafter, the expression of selected genes of the LPS and LTA pathway and inflammatory response were evaluated. Furthermore, it was assessed whether LPS affects inflammatory response and structural integrity of claw explants. Therefore, claw explants were incubated with LPS for 4 h to assess the expression of selected genes and for 24 h to evaluate tissue integrity via separation force. LPS strongly affected the expression of genes related to inflammation (NFkB, TNF-α, IL1B, IL6, CXCL8, MMP9) in RECs. LTA induced a delayed and weaker inflammatory response than LPS. In claw explants, LPS affected tissue integrity, as there was a concentration-dependent decrease of separation force. Incubation time had a strong effect on inflammatory genes in claw explants. Our data suggest that endotoxins can induce a local inflammatory response in the rumen epithelium. Furthermore, translocation of LPS might negatively impact claw health.

scholarly journals Acute Management Should Be Optimized in Patients with Less Specific Stroke Symptoms: Findings from a Retrospective Observational Study

2021 ◽  
Vol 10 (5) ◽  
pp. 1143
Author(s):  
Simona Halúsková ◽  
Roman Herzig ◽  
Dagmar Krajíčková ◽  
Abduljabar Hamza ◽  
Antonín Krajina ◽  
...  
Keyword(s):  
Wide Spectrum ◽  
Intravenous Thrombolysis ◽  
National Institutes Of Health ◽  
Vascular Territory ◽  
Anterior Circulation ◽  
Point Increase ◽  
Single Center Study ◽  
Mouth Corner ◽  
Specific Symptoms ◽  
The Impact

Anterior circulation stroke (ACS) is associated with typical symptoms, while posterior circulation stroke (PCS) may cause a wide spectrum of less specific symptoms. We aim to assess the correlation between the initial presentation of acute ischemic stroke (AIS) symptoms and the treatment timeline. Using a retrospective, observational, single-center study, the set consists of 809 AIS patients treated with intravenous thrombolysis (IVT) and/or endovascular treatment (EVT). We investigate the impact of baseline clinical AIS symptoms and the affected vascular territory on recanalization times in patients treated with IVT only and EVT (±IVT). Regarding the IVT-only group, increasing the National Institutes of Health Stroke Scale (NIHSS) score on admission and speech difficulties are associated with shorter (by 1.59 ± 0.76 min per every one-point increase; p = 0.036, and by 24.56 ± 8.42 min; p = 0.004, respectively) and nausea/vomiting with longer (by 43.72 ± 13.13 min; p = 0.001) onset-to-needle times, and vertigo with longer (by 8.58 ± 3.84 min; p = 0.026) door-to-needle times (DNT). Regarding the EVT (±IVT) group, coma is associated with longer (by 22.68 ± 6.05 min; p = 0.0002) DNT, anterior circulation stroke with shorter (by 47.32 ± 16.89 min; p = 0.005) onset-to-groin time, and drooping of the mouth corner with shorter (by 20.79 ± 6.02 min; p = 0.0006) door-to-groin time. Our results demonstrate that treatment is initiated later in strokes with less specific symptoms than in strokes with typical symptoms.

scholarly journals Evaluating ‘homegrown’ research networks in Africa

2018 ◽  
Vol 114 (3/4) ◽  
Author(s):  
Camilla Adelle ◽  
Nico Elema ◽  
Ereck Chakauya ◽  
David Benson
Keyword(s):  
Wide Spectrum ◽  
Evaluation Framework ◽  
Evidence Based ◽  
Regional Research ◽  
Research Networks ◽  
Sustainable Resources ◽  
Science Policy Interface ◽  
Mere Existence ◽  
The Impact

Attempts to improve the policy environment have led to a growing pressure on governments in Africa to embark on policymaking that is more evidence based and considers a wide spectrum of scientific and indigenous knowledge. Local – or ‘homegrown’ – research networks on the continent can help strengthen the role of scientific knowledge in policymaking by increasing the capacity of researchers and by enhancing the visibility and communication of the research produced. While a large number of regional and sub-regional research networks have sprung up in Africa, the mere existence of networks does not guarantee their success. In reality, the impact of research networks on the science–policy interface depends on how well the networks operate in practice. We present a framework for evaluating the effectiveness of research networks in a way that is comparable across networks. The evaluation framework was used to evaluate two sub-regional research networks: the NEPAD Southern African Networks of Water Centres of Excellence (SANWACTE) and the NEPAD Southern African Network for Biosciences (SANBio). The evaluation revealed some shared constraints limiting the effectiveness of both networks, including uneven regional representation, asymmetry between network members, and difficulties in securing sufficient, diverse and sustainable resources. Further research into network design and funding models is suggested in order to enhance the role of these networks in providing locally appropriate knowledge for policymaking on the continent.

scholarly journals The golden mimicry complex uses a wide spectrum of defence to deter a community of predators

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Stano Pekár ◽  
Lenka Petráková ◽  
Matthew W Bulbert ◽  
Martin J Whiting ◽  
Marie E Herberstein
Keyword(s):  
Wide Spectrum ◽  
In The Wild ◽  
Vertebrate Predators ◽  
Additive Influence ◽  
Multiple Species

Mimicry complexes typically consist of multiple species that deter predators using similar anti-predatory signals. Mimics in these complexes are assumed to vary in their level of defence from highly defended through to moderately defended, or not defended at all. Here, we report a new multi-order mimicry complex that includes at least 140 different putative mimics from four arthropod orders including ants, wasps, bugs, tree hoppers and spiders. All members of this mimicry complex are characterised by a conspicuous golden body and an ant Gestalt, but vary substantially in their defensive traits. However, they were similarly effective at deterring predators - even mildly defended mimics were rarely eaten by a community of invertebrate and vertebrate predators both in the wild and during staged trials. We propose that despite the predominance of less defended mimics the three predatory guilds avoid the mimics because of the additive influence of the various defensive traits.

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