scholarly journals ANALYSIS OF MIXED DATA TO SELECT BANANAS CLONES (Musa SPP.) TO BE INCLUDED IN A GERMPLASM BANK

2021 ◽  
Vol 32 (Issue 1) ◽  
pp. 35-42
Author(s):  
A. P. Del Medico ◽  
G. Tenaglia ◽  
A. L. Lavalle ◽  
M. S. Vitelleschi ◽  
G. R. Pratta

In an asexually reproducing hybrid such as banana (Musa spp.), the assessment of clones in the short term is limited because replications are frequently unavailable in the proper number. The aim of this work is to propose the Multiple Factor Analysis of Mixed Data (MFAmix) as a tool for establishing objective criteria to identify banana clones that preserve variability for qualitative and quantitative variables. In the long term, the aim is the development of a banana germplasm bank. MFAmix was applied on a population composed of 124 banana clones collected from different farmers’ fields and four controls. Two groups of variables related to the agronomic aptitude of the clones were evaluated, one composed of nine quantitative variables, and the other, composed of three dichotomous qualitative variables. A Selection Index (SI) was built from the MFAmix coordinates in order to rank the clones and select a subset that allows to preserve the existing genetic variability. The first two axes of MFAmix explained a 49.47% of the total data variability. The set of the banana clones was successfully characterized based on quantitative and qualitative variables. In the long term, the creation of a banana germplasm bank should consider the height and diameter of the plant, the rachis bunch weight and the hands weight, and the qualitative variable plant leafiness. Key words: asexual hybrid, collection of germplasm, multivariate analysis, Musaceae.

2021 ◽  
Vol 32 (Issue 1) ◽  
pp. 25-42
Author(s):  
A. P. Del Medico ◽  
G. Tenaglia ◽  
A. L. Lavalle ◽  
M. S. Vitelleschi ◽  
G. R. Pratta

In an asexually reproducing hybrid such as banana (Musa spp.), the assessment of clones in the short term is limited because replications are frequently unavailable in the proper number. The aim of this work is to propose the Multiple Factor Analysis of Mixed Data (MFAmix) as a tool for establishing objective criteria to identify banana clones that preserve variability for qualitative and quantitative variables. In the long term, the aim is the development of a banana germplasm bank. MFAmix was applied on a population composed of 124 banana clones collected from different farmers’ fields and four controls. Two groups of variables related to the agronomic aptitude of the clones were evaluated, one composed of nine quantitative variables, and the other, composed of three dichotomous qualitative variables. A Selection Index (SI) was built from the MFAmix coordinates in order to rank the clones and select a subset that allows to preserve the existing genetic variability. The first two axes of MFAmix explained a 49.47% of the total data variability. The set of the banana clones was successfully characterized based on quantitative and qualitative variables. In the long term, the creation of a banana germplasm bank should consider the height and diameter of the plant, the rachis bunch weight and the hands weight, and the qualitative variable plant leafiness. Key words: asexual hybrid, collection of germplasm, multivariate analysis, Musaceae.


2021 ◽  
Author(s):  
Filippo Guzzon ◽  
Maraeva Gianella ◽  
Jose Alejandro Velazquez Juarez ◽  
Cesar Sanchez Cano ◽  
Denise E Costich

Abstract Background and Aims The long-term conservation of seeds of plant genetic resources is of key importance for food security and preservation of agrobiodiversity. Nevertheless, there is scarce information available about seed longevity of many crops under germplasm bank conditions. Methods Through germination experiments as well as the analysis of historical monitoring data, we studied the decline in viability manifested by 1000 maize (Zea mays subsp. mays) seed accessions conserved for an average of 48 years at the CIMMYT germplasm bank, the largest maize seedbank in the world, under two cold storage conditions: an active (–3 °C; intended for seed distribution) and a base conservation chamber (–15 °C; for long-term conservation). Key Results Seed lots stored in the active chamber had a significantly lower and more variable seed germination, averaging 81.4 %, as compared with the seed lots conserved in the base chamber, averaging 92.1 %. The average seed viability detected in this study was higher in comparison with that found in other seed longevity studies on maize conserved under similar conditions. A significant difference was detected in seed germination and longevity estimates (e.g. p85 and p50) among accessions. Correlating seed longevity with seed traits and passport data, grain type showed the strongest correlation, with flint varieties being longer lived than floury and dent types. Conclusions The more rapid loss of seed viability detected in the active chamber suggests that the seed conservation approach, based on the storage of the same seed accessions in two chambers with different temperatures, might be counterproductive for overall long-term conservation and that base conditions should be applied in both. The significant differences detected in seed longevity among accessions underscores that different viability monitoring and regeneration intervals should be applied to groups of accessions showing different longevity profiles.


1999 ◽  
Vol 1999 ◽  
pp. 122-122 ◽  
Author(s):  
A.M. van Heelsum ◽  
R.M. Lewis ◽  
D.W. Jones ◽  
W. Haresign ◽  
M.H. Davies

Currently fewer than 50% of UK lambs produce carcasses of acceptable quality for the domestic and export markets, which compromises the competitiveness of sheep farming. Carcass quality can be changed by selection, and this is now being taken advantage of in terminal sire breeds and, to a lesser extent, in hill breeds. However, little attention has yet been focused on the crossing breeds, which have relatively poor carcass quality, in spite of the large impact such breeds have on the slaughter generation. Recently, a long-term project began to develop breeding programmes relevant to crossing sire (‘longwool’) breeds. Its objective is to produce a selection index to improve carcass quality without compromising the reproductive performance or maternal ability of these breeds. The Bluefaced Leicester is the most prevalent crossing sire breed with its crossbred (‘Mule’) daughters out of draft hill ewes accounting for 89% of crossbred (longwool x hill) ewes in the UK (Pollot, 1998).


Energies ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 4123 ◽  
Author(s):  
Lu Yang ◽  
Lei Yang ◽  
Kung-Cheng Ho ◽  
Shigeyuki Hamori

This study employed a dynamic conditional correlation–mixed-data sampling (DCC–MIDAS) approach and panel data analysis to examine the factors that influence the long-term correlation between crude oil and stock markets. Our study shows that there is a positive long-term conditional correlation between oil prices and stock markets, except during the 2008 global financial crisis and the 2011 European debt crisis. We also found that macroeconomic factors have a significant impact on this correlation. Specifically, risk-free rate has a positive effect, whereas economic activity and credit risk has a negative effect. Our results provide useful information for investors and monetary authorities.


2003 ◽  
Vol 34 (2) ◽  
pp. 138-153 ◽  
Author(s):  
A. Lynn Williams ◽  
Mary Elbert

Purpose: This study involved prospective longitudinal data on 5 late talkers to provide information about the course of phonological development in order to identify possible predictors of delayed versus deviant development. Method: Five children (3 boys, 2 girls) were identified as late talkers and divided into a younger group and an older group. Each child was followed monthly for 10 to 12 months (22–33 months for the younger group and 30–42 months for the older group). Two types of monthly language samples (free play and elicited) were obtained to describe the individual courses of phonological development for each child. Independent and relational analyses were completed at each age to describe word-initial and word-final phonetic inventories, syllable structure, syllable diversity, percentage of consonants correct (PCC), sound variability, and error patterns. Results: The results indicated that 3 of the children resolved their late onset of speech by 33 to 35 months of age. In addition to quantitative factors, (e.g., limited phonetic inventory, lower PCC, and more sound errors), qualitative variables (e.g., atypical error patterns, greater sound variability, and slower rate of resolution) also were identified as potential markers of long-term phonological delay. Clinical Implications: This study provides information to clinicians so they can identify those children who are less likely to resolve their late onset of phonological development without direct intervention. Procedures are described for assessing early linguistic behaviors that incorporate independent and relational analyses on more extensive speech samples (elicited and free play). From these analyses, clinicians can examine quantitative and qualitative variables to differentiate phonological delay from deviance.


2019 ◽  
Vol 5 (3) ◽  
pp. 205630511986546 ◽  
Author(s):  
Marco Bastos ◽  
Johan Farkas

This article presents a typological study of the Twitter accounts operated by the Internet Research Agency (IRA), a company specialized in online influence operations based in St. Petersburg, Russia. Drawing on concepts from 20th-century propaganda theory, we modeled the IRA operations along propaganda classes and campaign targets. The study relies on two historical databases and data from the Internet Archive’s Wayback Machine to retrieve 826 user profiles and 6,377 tweets posted by the agency between 2012 and 2017. We manually coded the source as identifiable, obfuscated, or impersonated and classified the campaign target of IRA operations using an inductive typology based on profile descriptions, images, location, language, and tweeted content. The qualitative variables were analyzed as relative frequencies to test the extent to which the IRA’s black, gray, and white propaganda are deployed with clearly defined targets for short-, medium-, and long-term propaganda strategies. The results show that source classification from propaganda theory remains a valid framework to understand IRA’s propaganda machine and that the agency operates a composite of different user accounts tailored to perform specific tasks, including openly pro-Russian profiles, local American and German news sources, pro-Trump conservatives, and Black Lives Matter activists.


2020 ◽  
Author(s):  
Zhuying Chen ◽  
David B. Grayden ◽  
Anthony N. Burkitt ◽  
Udaya Seneviratne ◽  
Wendyl J. D’Souza ◽  
...  

AbstractObjectiveTo assess the variability in the rates and locations of high-frequency activity (HFA) and epileptiform spikes after electrode implantation, and to examine the long-term patterns of HFA using ambulatory intracranial EEG (iEEG) recordings.MethodsContinuous iEEG recordings obtained over an average of 1.4 years from 15 patients with drug-resistant focal epilepsy were used in this study. HFA was defined as high-frequency events with amplitudes clearly larger than the background, which was automatically detected using a custom algorithm. High-frequency oscillations (HFOs) were also visually annotated by three neurologists in randomly sampled segments of the total data. The automatically detected HFA was compared with the visually marked HFOs. The variations of HFA rates were compared with spikes and seizures on patient-specific and electrode-specific bases.ResultsHFA was a more general event that encompassed HFOs manually annotated by different reviewers. HFA and spike rates had high amounts of intra- and inter-patient variability. The rates and locations of HFA and spikes took up to weeks to stabilize after electrode implantation in some patients. Both HFA and spike rates showed strong circadian rhythms in all patients and some also showed multiday cycles. Furthermore, the circadian patterns of HFA and spike rates had patient-specific correlations with seizures, which tended to vary across electrodes.ConclusionsAnalysis of HFA and epileptiform spikes should account for post-implantation variability. Like seizures, HFA and epileptiform spikes show circadian rhythms. However, the circadian profiles can vary spatially within patients and their correlations to seizures are patient-specific.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yue Shang ◽  
Xiaodan Chen ◽  
Yifeng Zhang ◽  
Yu Wei

The aim of this paper is to identify the quantitative impacts of the infectious disease pandemic on the permanent volatility of precious metal and crude oil futures from a long-term perspective by using a recently constructed Infectious Disease Equity Market Volatility Tracker (ID-EMV) to capture the epidemic severity and with a novel mixed data sampling GARCH (GARCH-MIDAS) method. Different from the extant literature only focusing on the short-term influences of the COVID-19 epidemic on commodity futures market, this paper shows that the infectious disease pandemic does have significant and positive impacts on the permanent (long-term) volatilities of precious metal and crude oil futures markets lasting for at least up to 12 months. In addition, these specific impacts on crude oil futures are greater than those on precious metal futures. Finally, we find that the infectious disease epidemic has larger impacts on gold (WTI oil) futures than those on silver (Brent oil) futures. All these findings are robust after controlling the negative influences of lagged long-run realized volatility in commodity futures markets.


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