Lack of genetic evidence for the subspeciation of Pisaster ochraceus (Echinodermata: Asteroidea) in the north-eastern Pacific Ocean

2008 ◽  
Vol 88 (2) ◽  
pp. 395-400 ◽  
Author(s):  
Sarita Frontana-Uribe ◽  
Jorge de la Rosa-Vélez ◽  
Luis Enríquez-Paredes ◽  
Lydia B. Ladah ◽  
Laura Sanvicente-Añorve
Keyword(s):  
Genetic Structure ◽  
Single Species ◽  
Original Data ◽  
Central Position ◽  
Western Coast ◽  
Data Set ◽  
Pisaster Ochraceus ◽  
The North ◽  
Point Conception ◽  
Minimum Spanning Network

The existence of two Pisaster ochraceus subspecies has been proposed; one located northwards (P. ochraceus ochraceus) and the other southwards (Pisaster ochraceus segnis) from Point Conception. We used polymerase chain reaction–restriction fragment length polymorphism of the CO I and CO III mitochondrial genes to assess the degree of population structure from 126 samples collected along the western coast of North America, from Vancouver, Canada to Punta San Carlos, of Baja California, Mexico. The genetic structure was tested through molecular analysis of variance and by Monte Carlo simulations of the original data set. The phylogeographical pattern was deduced from a minimum spanning network analysis. No genetic structure was detected. Instead, a high degree of genetic homogeneity along the species distribution was evident from haplotype frequencies at each location. Two haplotypes, Po1 and Po5, were predominant along the distribution and were considered ancestral because of their central position in the minimum spanning network. Since Pisaster ochraceus depicts a planktotrophic larval stage with very long duration before settlement, it seems to be able to surpass the biogeographical boundary that limits other species around Point Conception, thereby maintaining homogeneity of its genetic pool. Results of this study recognize P. ochraceus as a single species.

Microsatellite analyses of spatial genetic structure in darkblotched rockfish (Sebastes crameri): Is pooling samples safe?

2005 ◽  
Vol 62 (8) ◽  
pp. 1874-1886 ◽  
Author(s):  
Daniel Gomez-Uchida ◽  
Michael A Banks
Keyword(s):  
Genetic Structure ◽  
Isolation By Distance ◽  
Spatial Genetic Structure ◽  
Geographic Distance ◽  
Original Data ◽  
Dispersal Distance ◽  
Data Set ◽  
Limited Dispersal ◽  
Composite Samples ◽  
Microsatellite Analyses

By pooling or removing samples of small size, we investigated how results from microsatellite analyses of spatial genetic structure in darkblotched rockfish (Sebastes crameri) were affected. Genotypes from six and seven microsatellite loci from 1206 specimens collected offshore from Washington to California were employed in the analyses. Sample sizes varied greatly among locations (n = 11–114). When adjacent samples of n < 25 were pooled using an absolute genetic distance (FST ≤ 0), the correlation between genetic and geographic distance found in the original data set increased nearly twofold, and overall FST (95% confidence interval) increased from 0.001 (0.000–0.002) to 0.002 (0.001–0.003). Removing samples where n < 25 gave a similar result, yet the correlation increase was smaller. Another pooling strategy based on similarity tests allowed larger sizes in composite samples (n > 100) and further increased the correlation, although this strategy did not raise overall FST. These results indicate that under genetic isolation by distance, excessive pooling might not enhance the overall genetic differentiation among populations. The regression slope in isolation by distance plots was robust throughout all treatments, and its value suggests limited dispersal distance on this species.

Rotational Characteristics of the Green Solar Corona: 1947-1991

1994 ◽  
Vol 144 ◽  
pp. 139-141 ◽  
Author(s):  
J. Rybák ◽  
V. Rušin ◽  
M. Rybanský
Keyword(s):  
Solar Corona ◽  
World Wide ◽  
Rotation Period ◽  
Original Data ◽  
Coronal Emission ◽  
Time Intervals ◽  
Data Set ◽  
The World ◽  
Coronal Emission Line ◽  
Homogeneous Data

AbstractFe XIV 530.3 nm coronal emission line observations have been used for the estimation of the green solar corona rotation. A homogeneous data set, created from measurements of the world-wide coronagraphic network, has been examined with a help of correlation analysis to reveal the averaged synodic rotation period as a function of latitude and time over the epoch from 1947 to 1991.The values of the synodic rotation period obtained for this epoch for the whole range of latitudes and a latitude band ±30° are 27.52±0.12 days and 26.95±0.21 days, resp. A differential rotation of green solar corona, with local period maxima around ±60° and minimum of the rotation period at the equator, was confirmed. No clear cyclic variation of the rotation has been found for examinated epoch but some monotonic trends for some time intervals are presented.A detailed investigation of the original data and their correlation functions has shown that an existence of sufficiently reliable tracers is not evident for the whole set of examinated data. This should be taken into account in future more precise estimations of the green corona rotation period.

Electing the Senate

2017 ◽  
Author(s):  
Wendy J. Schiller ◽  
Charles Stewart III
Keyword(s):  
Original Data ◽  
State Legislators ◽  
Internal Conflict ◽  
Data Set ◽  
Senate Elections ◽  
Political Actors ◽  
The Public ◽  
Seventeenth Amendment ◽  
The People ◽  
Election Process

From 1789 to 1913, U.S. senators were not directly elected by the people—instead the Constitution mandated that they be chosen by state legislators. This radically changed in 1913, when the Seventeenth Amendment to the Constitution was ratified, giving the public a direct vote. This book investigates the electoral connections among constituents, state legislators, political parties, and U.S. senators during the age of indirect elections. The book finds that even though parties controlled the partisan affiliation of the winning candidate for Senate, they had much less control over the universe of candidates who competed for votes in Senate elections and the parties did not always succeed in resolving internal conflict among their rank and file. Party politics, money, and personal ambition dominated the election process, in a system originally designed to insulate the Senate from public pressure. The book uses an original data set of all the roll call votes cast by state legislators for U.S. senators from 1871 to 1913 and all state legislators who served during this time. Newspaper and biographical accounts uncover vivid stories of the political maneuvering, corruption, and partisanship—played out by elite political actors, from elected officials, to party machine bosses, to wealthy business owners—that dominated the indirect Senate elections process. The book raises important questions about the effectiveness of Constitutional reforms, such as the Seventeenth Amendment, that promised to produce a more responsive and accountable government.

MONITORING THE DYNAMICS OF THERMOABRASION COASTS AT KHARASAVEY AREA, WESTERN YAMAL (KARA SEA)

2017 ◽  
Author(s):  
Dmitry Kuznetsov ◽  
Dmitry Kuznetsov ◽  
Anatoliy Kamalov ◽  
Anatoliy Kamalov ◽  
Nataliya Belova ◽  
...  
Keyword(s):  
Human Impact ◽  
Remote Sensing Data ◽  
Kara Sea ◽  
Motor Vehicles ◽  
Yamal Peninsula ◽  
Western Coast ◽  
Frozen Ground ◽  
Coastal Dynamics ◽  
The North ◽  
Ice Content

The dynamics of thermoabrasion coasts on loose sediments under permafrost conditions are highly variable due to several factors: length of the dynamic period of the year, mechanic composition of the frozen ground and its ice content, hydrometeorological conditions, and human impact. Multiannual monitoring of the coastal zone was carried out by Lab. Geoecology of the North (Moscow State University) at the 22 km long Kharasavey deposit site, Western Coast of Yamal Peninsula (Kara Sea). The methods include direct measurements and observations (repeated topographic survey of shore transects from 1981 to 2012) along with remote sensing data analysis (images from 1964 to 2011). This allowed producing detailed characteristics of coastal dynamics. At the site, thermoabrasion coasts occupy the most part, and accumulative coasts are present in the north. Data on natural relief forming factors and ground composition are included in the detailed geomorphologic map of the site. Shore retreat rate shows correlation to amounts of wind-wave energy and to specific wind directions. Human impact on the coast includes dredging at the port channel, mining of sand, driving motor vehicles, and deposition of construction debris. Relations between shore retreat rate and aforementioned factors were studied, including dependencies on ice content, and shore segmentation was carried out. This allows for coastal dynamics forecasts in the region.

Maritime and River Traders, Landing Places, and Emporia Ports in the Merovingian Period in and Around the Low Countries

2020 ◽  
pp. 763-796
Author(s):  
Dries Tys
Keyword(s):  
North Sea ◽  
Institutional Economics ◽  
New Institutional Economics ◽  
Central Position ◽  
Economic Activities ◽  
Early Medieval ◽  
Low Countries ◽  
Long Distance ◽  
The North ◽  
The North Sea

The origin, rise, and dynamics of coastal trade and landing places in the North Sea area between the sixth and eighth centuries must be understood in relation to how coastal regions and seascapes acted as arenas of contact, dialogue, and transition. Although the free coastal societies of the early medieval period were involved in regional to interregional or long-distance trade networks, their economic agency must be understood from a bottom-up perspective. That is, their reproduction strategies must be studied in their own right, independent from any teleological construction about the development of trade, markets, or towns for that matter. This means that the early medieval coastal networks of exchange were much more complex and diverse than advocated by the simple emporium network model, which connected the major archaeological sites along the North Sea coast. Instead, coastal and riverine dwellers often possessed some form of free status and large degrees of autonomy, in part due to the specific environmental conditions of the landscapes in which they dwelled. The wide estuarine region of the Low Countries, between coastal Flanders in the south and Friesland in the north, a region with vast hinterlands and a central position in northwestern Europe, makes these developments particularly clear. This chapter thus pushes back against longstanding assumptions in scholarly research, which include overemphasis of the influence of large landowners over peasant economies, and on the prioritization of easily retrievable luxuries over less visible indicators of bulk trade (such as wood, wool, and more), gift exchange, and market trade. The approach used here demonstrates that well-known emporia or larger ports of trade were embedded in the economic activities and networks of their respective hinterlands. Early medieval coastal societies and their dynamics are thus better understood from the perspective of integrated governance and economy (“new institutional economics”) in a regional setting.

Styles of Representation in Constituencies in the Homeland and Abroad: The Case of Italy

2020 ◽  
Author(s):  
Eva Østergaard-Nielsen ◽  
Stefano Camatarri
Keyword(s):  
Original Data ◽  
Role Orientation ◽  
International Mobility ◽  
Data Set ◽  
Democratic Representation ◽  
Public Debates ◽  
At Home

Abstract The role orientation of political representatives and candidates is a longstanding concern in studies of democratic representation. The growing trend in countries to allow citizens abroad to candidate in homeland elections from afar provides an interesting opportunity for understanding how international mobility and context influences ideas of representation among these emigrant candidates. In public debates, emigrant candidates are often portrayed as delegates of the emigrant constituencies. However, drawing on the paradigmatic case of Italy and an original data set comprising emigrant candidates, we show that the perceptions of styles of representation abroad are more complex. Systemic differences between electoral districts at home and abroad are relevant for explaining why and how candidates develop a trustee or delegate orientation.

Do the Heterogeneous Determinants of Repayment Affect Differently across Borrowers of Diverse Credit Sources in Rural Assam? A Double Hurdle Approach

2021 ◽  
pp. 245513332110316
Author(s):  
Tiken Das ◽  
Pradyut Guha ◽  
Diganta Das
Keyword(s):  
Rural Areas ◽  
Probit Model ◽  
Original Data ◽  
Community Based ◽  
Data Set ◽  
Brahmaputra Valley ◽  
Double Hurdle ◽  
Instrumental Variable Probit ◽  
Instrumental Variable Probit Model

This study made an attempt to answer the question: Do the heterogeneous determinants of repayment affect the borrowers of diverse credit sources differently? The study is based on data collected from 240 households from three districts in the lower Brahmaputra valley of Assam through a carefully designed primary survey. Besides, the study uses the double hurdle approach and the instrumental variable probit model to reduce possible selection bias. It observes better repayment performance among formal borrowers, followed by semiformal borrowers, while occupation wise it is prominent among organised employees. It has been found that in general, the household characteristics, loan characteristics and location-specific characteristics significantly affect repayment performance of borrowers. However, the nature of impact of the factors influencing repayment performance is remarkably different across credit sources. It ignores the role of traditional community-based organisations in rural Assam while analysing the determinants of repayment performance. The study also recommends for ensuring productive opportunities and efficient market linkages in rural areas of Assam. The study is based on an original data set that has specially been collected to examine question that—do the heterogeneous determinants of repayment affect the borrowers of diverse credit sources differently in the lower Brahmaputra valley of Assam—which has not been studied before.

scholarly journals Data Augmentation Using Generative Adversarial Network for Automatic Machine Fault Detection Based on Vibration Signals

2021 ◽  
Vol 11 (5) ◽  
pp. 2166
Author(s):  
Van Bui ◽  
Tung Lam Pham ◽  
Huy Nguyen ◽  
Yeong Min Jang
Keyword(s):  
Fault Detection ◽  
Data Augmentation ◽  
Model Performance ◽  
Original Data ◽  
Fault Classification ◽  
Training Process ◽  
Generative Adversarial Network ◽  
Data Set ◽  
Adversarial Network ◽  
Machine Fault

In the last decade, predictive maintenance has attracted a lot of attention in industrial factories because of its wide use of the Internet of Things and artificial intelligence algorithms for data management. However, in the early phases where the abnormal and faulty machines rarely appeared in factories, there were limited sets of machine fault samples. With limited fault samples, it is difficult to perform a training process for fault classification due to the imbalance of input data. Therefore, data augmentation was required to increase the accuracy of the learning model. However, there were limited methods to generate and evaluate the data applied for data analysis. In this paper, we introduce a method of using the generative adversarial network as the fault signal augmentation method to enrich the dataset. The enhanced data set could increase the accuracy of the machine fault detection model in the training process. We also performed fault detection using a variety of preprocessing approaches and classified the models to evaluate the similarities between the generated data and authentic data. The generated fault data has high similarity with the original data and it significantly improves the accuracy of the model. The accuracy of fault machine detection reaches 99.41% with 20% original fault machine data set and 93.1% with 0% original fault machine data set (only use generate data only). Based on this, we concluded that the generated data could be used to mix with original data and improve the model performance.

scholarly journals Regional differences in the evolution of the merger of /ʃ/ and /ç/ in Luxembourgish

2021 ◽  
pp. 1-18
Author(s):  
François Conrad
Keyword(s):  
Language Contact ◽  
Sound Change ◽  
Young Generation ◽  
The South ◽  
Data Set ◽  
West Germanic ◽  
The North ◽  
Minimal Pairs ◽  
Old Men ◽  
Middle Generation

The merger of post-alveolar /ʃ/ and palatal /ç/ into alveolopalatal /ɕ/ has recently gained growing interest in sociophonetic research, especially in the Middle German dialect area. In Luxembourgish, a Continental West Germanic language, the sound change has been linked to age differences, while its origins remain unclear. Two studies with a regional focus are presented in this paper. The first study examines the merger in the Centre and the South of Luxembourg. The acoustic examination of both the spectral peak and the centre of gravity of a spoken data set of five minimal pairs embedded in read and orally translated sentences from 48 speakers (three generations (old generation, 65–91 years; middle generation, 40–64 years; young generation, 20–39 years; each generation, n = 16), men and women) reveals interesting results related to their regional background. In the old generation, the merger is further advanced in the speech of old men from the former mining region in the South compared to their peers in the Centre, the former leading this sound change. On the other hand, young speakers in both regions produce only alveolopalatal /ɕ/, the merger being complete in this generation. The second study presents exploratory data from the East and the North of the country. The analysis of this smaller sample (n = 6 speakers) reveals patterns similar to the central region. Pointing to language contact with Romance in the South as cradle and/or catalyser of the merger, these results not only give further clues as to the development in Luxembourg, but also add to a deeper understanding of sound changes in process in complex sibilant systems.

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