scholarly journals Population genomics of Wolbachia and mtDNA in Drosophila simulans from California

2017 ◽  
Author(s):  
Sarah Signor
Keyword(s):  
Population Genomics ◽  
Nuclear Genome ◽  
Protein Processing ◽  
Drosophila Simulans ◽  
Future Research ◽  
Short Term ◽  
Low Genetic Diversity ◽  
Term Evolution ◽  
Filarial Nematodes ◽  
Recent Origin

ABSTRACTWolbachia pipientis is an intracellular endosymbiont in fecting many arthropods and filarial nematodes. Little is known about the short-term evolution of Wolbachia or its interaction with its host. Wolbachia is maternally inherited, resulting in co-inheritance of mitochondrial organelles such as mtDNA. Here I explore the short-term evolution of Wolbachia, and the relationship between Wolbachia and mtDNA, using a large inbred panel of Drosophila simulans infected with the Wolbachia strain wRi. I find reduced diversity relative to expectation in both Wolbachia and mtDNA, but only mtDNA shows evidence of a recent selective sweep or population bottleneck. I estimate Wolbachia and mtDNA titre in each genotype, and I find considerable variation in both phenotypes, despite low genetic diversity in Wolbachia and mtDNA. A phylogeny of Wolbachia and of mtDNA show that both trees are largely unresolved, suggesting a recent origin of the infection and a single origin. Using Wolbachia and mtDNA titre as a phenotype, we perform an association analysis with the nuclear genome and find several regions implicated in the phenotype, including one which contains four CAAX-box protein processing genes. CAAX-box protein processing can be an important part of host-pathogen interactions in other systems, suggesting interesting directions for future research.

scholarly journals Intraspecific Diversity of Fission Yeast Mitochondrial Genomes

2019 ◽  
Vol 11 (8) ◽  
pp. 2312-2329 ◽  
Author(s):  
Yu-Tian Tao ◽  
Fang Suo ◽  
Sergio Tusso ◽  
Yan-Kai Wang ◽  
Song Huang ◽  
...  
Keyword(s):  
Fission Yeast ◽  
Population Genomics ◽  
De Novo ◽  
Model Organism ◽  
Nuclear Genome ◽  
Intraspecific Diversity ◽  
Future Research ◽  
Data Sets ◽  
Diversity Pattern ◽  
Mitochondrial Introns

Abstract The fission yeast Schizosaccharomyces pombe is an important model organism, but its natural diversity and evolutionary history remain under-studied. In particular, the population genomics of the S. pombe mitochondrial genome (mitogenome) has not been thoroughly investigated. Here, we assembled the complete circular-mapping mitogenomes of 192 S. pombe isolates de novo, and found that these mitogenomes belong to 69 nonidentical sequence types ranging from 17,618 to 26,910 bp in length. Using the assembled mitogenomes, we identified 20 errors in the reference mitogenome and discovered two previously unknown mitochondrial introns. Analyzing sequence diversity of these 69 types of mitogenomes revealed two highly distinct clades, with only three mitogenomes exhibiting signs of inter-clade recombination. This diversity pattern suggests that currently available S. pombe isolates descend from two long-separated ancestral lineages. This conclusion is corroborated by the diversity pattern of the recombination-repressed K-region located between donor mating-type loci mat2 and mat3 in the nuclear genome. We estimated that the two ancestral S. pombe lineages diverged about 31 million generations ago. These findings shed new light on the evolution of S. pombe and the data sets generated in this study will facilitate future research on genome evolution.

scholarly journals Intraspecific diversity of fission yeast mitochondrial genomes

2019 ◽  
Author(s):  
Yu-Tian Tao ◽  
Fang Suo ◽  
Sergio Tusso ◽  
Yan-Kai Wang ◽  
Song Huang ◽  
...  
Keyword(s):  
Fission Yeast ◽  
Population Genomics ◽  
De Novo ◽  
Model Organism ◽  
Nuclear Genome ◽  
Intraspecific Diversity ◽  
Future Research ◽  
Diversity Pattern ◽  
Mitochondrial Introns ◽  
Sequence Types

ABSTRACTThe fission yeastSchizosaccharomyces pombeis an important model organism, but its natural diversity and evolutionary history remain under-studied. In particular, the population genomics of theS. pombemitochondrial genome (mitogenome) has not been thoroughly investigated. Here, we assembled the complete circular-mapping mitogenomes of 192S. pombeisolatesde novo, and found that these mitogenomes belong to 69 non-identical sequence types ranging from 17618 bp to 26910 bp in length. Using the assembled mitogenomes, we identified 20 errors in the reference mitogenome and discovered two previously unknown mitochondrial introns. Analysing sequence diversity of these 69 types of mitogenomes revealed two highly distinct clades, with only three mitogenomes exhibiting signs of inter-clade recombination. This diversity pattern suggests that currently availableS. pombeisolates descend from two long-separated ancestral lineages. This conclusion is corroborated by the diversity pattern of the recombination-repressedK-region located between donor mating-type locimat2andmat3in the nuclear genome. We estimated that the two ancestralS. pombelineages diverged about 31 million generations ago. These findings shed new light on the evolution ofS. pombeand the datasets generated in this study will facilitate future research on genome evolution.

SHORT-TERM EVOLUTION OF FLOW & MORPHOLOGY IN AN ERODIBLE MEANDERING CHANNEL WITH & WITHOUT GROYNES

2018 ◽  
Vol 74 (4) ◽  
pp. I_1147-I_1152
Author(s):  
Saroj KARKI ◽  
Yuji HASEGAWA ◽  
Masakazu HASHIMOTO ◽  
Hajime NAKAGAWA ◽  
Kenji KAWAIKE
Keyword(s):  
Short Term ◽  
Meandering Channel ◽  
Term Evolution ◽  
Flow Morphology

Effects of Dipyridamole on the Short-Term Evolution of Glomerulonephritis

Nephron ◽  
1991 ◽  
Vol 58 (1) ◽  
pp. 13-16 ◽  
Author(s):  
S. Camara ◽  
J.P. de la Cruz ◽  
M.A. Frutos ◽  
P. Sanchez ◽  
Lopez de Novales ◽  
...  
Keyword(s):  
Short Term ◽  
Term Evolution

scholarly journals Staying Home, Staying Alive: Campus Food Pantry Student Clients’ Experiences During the COVID-19 Pandemic

2021 ◽  
pp. 193672442110356
Author(s):  
Elmira Jangjou
Keyword(s):  
Coping Strategies ◽  
Thematic Analysis ◽  
Future Research ◽  
Postsecondary Students ◽  
Structured Interviews ◽  
Short Term ◽  
Income Loss ◽  
Food Pantry ◽  
Global Pandemic ◽  
Seeking Help

In response to students’ food insecurity, a number of colleges and universities have taken action and established campus food pantries as part of their intervention plans. However, many of these pantries ceased operation due to COVID-19 campus shutdowns. The purpose of this study is to illustrate the short-term impacts of the COVID-19 pandemic on postsecondary students, who use a university-provided food pantry. Drawing from semi-structured interviews with 12 participants, the thematic analysis explored the initial coping strategies these students used to endure the pandemic. Findings revealed that many students experienced the immediate effects of the pandemic in the form of income loss, self-isolation, anxiety, and appetite change. Although the pandemic interrupted these students’ journeys to continue their studies and become independent in various ways, the affected students implemented various coping strategies, including seeking help from family or friends, using available resources, cooking at home, and even trying to save money. However, considering that the targeted population in this study was already at risk because of their basic needs insecurity, these postsecondary students require extra attention from their higher education institutions in the case of emergencies, such as a global pandemic. In addition to its timely and relevant findings, this study provides important avenues for future research and intervention efforts.

scholarly journals Catchment water quality in the year preceding and immediately following restoration of a drained afforested blanket bog

2021 ◽  
Author(s):  
Paul P. J. Gaffney ◽  
Mark H. Hancock ◽  
Mark A. Taggart ◽  
Roxane Andersen
Keyword(s):  
Water Quality ◽  
Nutrient Release ◽  
Pass Rate ◽  
Future Research ◽  
Negative Effects ◽  
Short Term ◽  
Peatland Restoration ◽  
Blanket Bog ◽  
Quality Threshold ◽  
Policy Incentives

AbstractThe restoration of drained afforested peatlands, through drain blocking and tree removal, is increasing in response to peatland restoration targets and policy incentives. In the short term, these intensive restoration operations may affect receiving watercourses and the biota that depend upon them. This study assessed the immediate effect of ‘forest-to-bog’ restoration by measuring stream and river water quality for a 15 month period pre- and post-restoration, in the Flow Country peatlands of northern Scotland. We found that the chemistry of streams draining restoration areas differed from that of control streams following restoration, with phosphate concentrations significantly higher (1.7–6.2 fold, mean 4.4) in restoration streams compared to the pre-restoration period. This led to a decrease in the pass rate (from 100 to 75%) for the target “good” quality threshold (based on EU Water Framework Directive guidelines) in rivers in this immediate post-restoration period, when compared to unaffected river baseline sites (which fell from 100 to 90% post-restoration). While overall increases in turbidity, dissolved organic carbon, iron, potassium and manganese were not significant post-restoration, they exhibited an exaggerated seasonal cycle, peaking in summer months in restoration streams. We attribute these relatively limited, minor short-term impacts to the fact that relatively small percentages of the catchment area (3–23%), in our study catchments were felled, and that drain blocking and silt traps, put in place as part of restoration management, were likely effective in mitigating negative effects. Looking ahead, we suggest that future research should investigate longer term water quality effects and compare different ways of potentially controlling nutrient release.

scholarly journals Multiple Pedestrians and Vehicles Tracking in Aerial Imagery Using a Convolutional Neural Network

2021 ◽  
Vol 13 (10) ◽  
pp. 1953
Author(s):  
Seyed Majid Azimi ◽  
Maximilian Kraus ◽  
Reza Bahmanyar ◽  
Peter Reinartz
Keyword(s):  
Neural Network ◽  
Deep Learning ◽  
Convolutional Neural Network ◽  
Object Tracking ◽  
Short Term Memory ◽  
Aerial Imagery ◽  
Future Research ◽  
Short Term ◽  
Term Memory ◽  
Long Short Term Memory

In this paper, we address various challenges in multi-pedestrian and vehicle tracking in high-resolution aerial imagery by intensive evaluation of a number of traditional and Deep Learning based Single- and Multi-Object Tracking methods. We also describe our proposed Deep Learning based Multi-Object Tracking method AerialMPTNet that fuses appearance, temporal, and graphical information using a Siamese Neural Network, a Long Short-Term Memory, and a Graph Convolutional Neural Network module for more accurate and stable tracking. Moreover, we investigate the influence of the Squeeze-and-Excitation layers and Online Hard Example Mining on the performance of AerialMPTNet. To the best of our knowledge, we are the first to use these two for regression-based Multi-Object Tracking. Additionally, we studied and compared the L1 and Huber loss functions. In our experiments, we extensively evaluate AerialMPTNet on three aerial Multi-Object Tracking datasets, namely AerialMPT and KIT AIS pedestrian and vehicle datasets. Qualitative and quantitative results show that AerialMPTNet outperforms all previous methods for the pedestrian datasets and achieves competitive results for the vehicle dataset. In addition, Long Short-Term Memory and Graph Convolutional Neural Network modules enhance the tracking performance. Moreover, using Squeeze-and-Excitation and Online Hard Example Mining significantly helps for some cases while degrades the results for other cases. In addition, according to the results, L1 yields better results with respect to Huber loss for most of the scenarios. The presented results provide a deep insight into challenges and opportunities of the aerial Multi-Object Tracking domain, paving the way for future research.

scholarly journals The Effectiveness of the Ecological Forest Rangers Policy in Southwest China

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 746
Author(s):  
Yifan Wang ◽  
Dengju Wang ◽  
Rong Zhao
Keyword(s):  
Poverty Alleviation ◽  
Southwest China ◽  
Rural Poverty ◽  
Ecological Effect ◽  
Income Growth ◽  
Future Research ◽  
Linkage Mechanism ◽  
Short Term ◽  
Forest Protection

To achieve the dual goal of poverty alleviation and ecological restoration, the policy of ecological forest rangers (EFRs) was implemented in rural poverty-stricken areas in China, where local residents commonly depend on nearby forest resources for livelihoods. This study aimed to analyze the short-term and long-term effectiveness of the EFRs policy in China mainly in poverty alleviation and income growth, with a brief discussion on the ecological effect of the policy. A questionnaire survey was conducted in four counties in the Karst rocky desertification region in southwest China. By combing through the early literature on REDD+, community forestry, leasehold forestry, etc., this paper summarizes the experience and lessons of similar community forest management models, aiming to explain the unsustainability of EFRs policy from the perspective of forest tenure and governance. The findings of the effectiveness analysis of EFRs policy in the four poverty-stricken counties reflect different degrees of effect in rural households with different income levels. We believe that the EFRs policy has played important roles in short-term regional poverty alleviation while its potential for long-term income growth has not been stimulated. For the amendment of EFRs policy, we put forward the following points: (1) It is necessary to redesign the selection and recruitment mechanism, as well as the exit mechanism of EFRs adapting to the local conditions. (2) It is advisable to further improve the local assessment and monitoring system of forest protection quality of EFRs and optimize the establishment of benefit linkage mechanism between protection effectiveness and EFRs remuneration. (3) The EFRs remuneration standards should be dynamically raised to assure the active participation of EFRs in forest protection. Furthermore, there is a need for one more effective integration model of forest protection and rural livelihoods improvement, which is considered as a potential future research direction.

Physical modeling of the cross-shore short-term evolution of protected and unprotected beach nourishments

2010 ◽  
Vol 37 (8-9) ◽  
pp. 777-789 ◽  
Author(s):  
M. Di Risio ◽  
I. Lisi ◽  
G.M. Beltrami ◽  
P. De Girolamo
Keyword(s):  
Physical Modeling ◽  
Short Term ◽  
Term Evolution ◽  
The Cross
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