scholarly journals Usefulness of Discriminant Analysis in the Morphometric Differentiation of Six Native Freshwater Species from Ecuador

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 111
Author(s):  
Ana Gonzalez-Martinez ◽  
Carmen De-Pablos-Heredero ◽  
Martin González ◽  
Jorge Rodriguez ◽  
Cecilio Barba ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Rural Communities ◽  
Development Program ◽  
Freshwater Species ◽  
Hydrographic Basin ◽  
Wilks Lambda ◽  
Morphological Variables ◽  
Morphometric Differentiation ◽  
Discriminant Power

The aim of this research was to find out the morphometric differentiation of six native freshwater species in the Guayas Hydrographic Basin (Ecuador) by means of discriminant analysis. A total of 1355 mature fishes (Cichlasoma festae, Andinoacara rivulatus, Dormitator latifrons, Bryncon dentex, Hoplias microlepis and Leporinus ecuadorensis) were captured and 27 morphometric measurements and 20 landmarks were used. Two-way analysis of variance with species and sex as fixed factors and discriminant analysis were applied. The selection of the most discriminant variables was made applying the F of Snedecor, Wilks’-Lambda and the 1-Tolerance. While sex within species had no significant effect on the morphology, differences among species were significant. Twenty-seven morphological variables showed highly significant differences among six native freshwater species. Nine biometric variables with high discriminant power were selected. The six species analyzed were discriminated by the morphometric models generated, thus showing that discriminant analysis was useful for differentiating species. The morphometric differentiation by discriminant analysis is a direct, simple and economic methodology to be applied in situ in rural communities. It favors the implementation of a livestock development program and it could be used with other native freshwater species in the Guayas Hydrographic Basin.

scholarly journals Morphological Variations of Wild Populations of Brycon dentex (Characidae, Teleostei) in the Guayas Hydrographic Basin (Ecuador). The Impact of Fishing Policies and Environmental Conditions

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1901
Author(s):  
Ana Gonzalez-Martinez ◽  
Carmen De-Pablos-Heredero ◽  
Martin González ◽  
Jorge Rodriguez ◽  
Cecilio Barba ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Environmental Conditions ◽  
Anthropogenic Activity ◽  
Freshwater Species ◽  
Fishing Pressure ◽  
Wild Populations ◽  
Morphometric Variation ◽  
Morphological Variations ◽  
Body Development ◽  
The Impact

The Guayas, located in Ecuador, is the largest basin in the Pacific Ocean and has an inventory of 123 native freshwater species. Most of these are endemic species that are threatened or at-risk due to anthropogenic activity and the modification, fragmentation, and destruction of habitats. The aim of this study was to determine the morphometric variation in three wild populations of Brycon dentex in the Guayas basin rivers and their connections to fishing management and environmental conditions. A total of 200 mature fish were captured, and 26 morphometric parameters were measured. The fishing policies (Hypothesis 1) and environmental conditions (Hypothesis 2) were considered fixed factors and were validated by t-tests. The morphological variation among the three populations (Hypothesis 3) was validated through a discriminant analysis. Fishing policies and resource management were found to generate morphological differences associated with body development. In addition, the environmental conditions were found to influence the size and structure of Brycon dentex populations. The analyzed populations were discriminated by the generated morphometric models, which differentiated Cluster 1 (Quevedo and Mocache rivers) with high fishing pressure from Cluster 2 (Pintado river) with medium–low fishing pressure. Morphometric differentiation by discriminant analysis is a direct and economic methodology that can be applied as an indicator of diversity maintenance.

scholarly journals Surface Electromyography Based Core Muscle Fatigue Analysis During Repetitive Plank Using Multivariate Dimensionality Reduction Methods in Boys Aged 12-14

2021 ◽  
Vol 21 (3) ◽  
pp. 253-263
Author(s):  
Abir Samanta ◽  
Sabyasachi Mukherjee
Keyword(s):  
Discriminant Analysis ◽  
Muscle Fatigue ◽  
Muscle Activity ◽  
Principal Component ◽  
Erector Spinae ◽  
P Value ◽  
Recruitment Strategies ◽  
Structure Matrix ◽  
Spine Stability ◽  
Wilks Lambda

The aims of the study were: 1. To analyse the discriminative power of neuromuscular components for classifying the pre and post muscle fatigued states. 2. To examine whether the modification of neural recruitment strategies become more/less heterogeneous due to fatigue. 3. To research the effect of Erector Spinae (ES) muscle activity collectively with Rectus Abdominis (RA) and External Oblique (EO) muscle activity to identify the reduced spine stability during fatiguing Plank.  Material and methods. Twelve boys (age – 12-14 years, height 148.75 ± 10 cm, body mass 38.9 ± 7.9 kg) participated in the study. Multivariate Discriminant Analysis (DA) and Principal Component Analysis (PCA) were applied to identify the changes in the pattern of the electromyographic signals during muscle fatigue. In DA the Wilks’ lambda, p-value, canonical correlation, classification percentage and structure matrix were used. To evaluate the component validity the standard limit for Kaiser-Meyer-Olkin (KMO) was set at ≥0.529 and the p-value of Bartlett’s test was ≤0.001. The eigenvalues ≥1 were used to determine the number of Principal Components (PCs). The satisfactory percentage of non-redundant residuals were set at ≤50% with standard value >0.05. The absolute value of average communality (x̄ h2) and component loadings were set at ≥0.6, ≥0.4 respectively.  Results. Standardized canonical discriminant analysis showed that pre and post fatigued conditions were significantly different (p = 0.000, Wilks’ lambda = 0.297, χ2 = 24.914, df=3). The structure matrix showed that the parameter that correlated highly with the discriminant function was ES ARV (0.514). The results showed that the classification accuracy was 95.8% between fatigued conditions. In PCA the KMO values were reduced [0.547Pre fatigue vs. 0.264Post fatigue]; the value of Bartlett’s sphericity test was in pre χ2 = 90.72 (p = 0.000) and post fatigue χ2 = 85.32 (p = 0.000); The Promax criterion with Kaiser Normalization was applied because the component rotation was non-orthogonal [Component Correlation Matrix (rCCM) = 0.520 Pre fatigue >0.3Absolute<0.357Post fatigue]. In pre fatigue two PCs (cumulative s2 – 80.159%) and post fatigue three PCs (cumulative s2 – 83.845%) had eigenvalues ≥1. The x̄ h2 increased [0.802 Pre fatigue vs. 0.838 Post fatigue] and the percentage of nonredundant residuals reduced [50% Pre fatigue vs. 44% Post fatigue] from pre to post fatigue.  Conclusions. The variability and heterogeneity increase in the myoelectric signals due to fatigue. The co-activity of antagonist ES muscle is significantly sensitive to identify the deteriorating spine stability during the fatiguing Plank. Highly correlated motor unit recruitment strategies between ES and RA, providing supportive evidence to the concept of shared agonist-antagonist motoneuron pool or “Common Drive” phenomenon during fatigue.

scholarly journals Automated Classification of Regional Meteorological Events in a Coastal Area Using In Situ Measurements

2020 ◽  
Vol 37 (4) ◽  
pp. 723-739 ◽  
Author(s):  
Anton Sokolov ◽  
Egor Dmitriev ◽  
Cyril Gengembre ◽  
Hervé Delbarre
Keyword(s):  
Discriminant Analysis ◽  
Coastal Area ◽  
Supervised Classification ◽  
Nearest Neighbors ◽  
Support Vector ◽  
Classification Algorithms ◽  
Quadratic Discriminant Analysis ◽  
Automated Classification ◽  
Sea Breezes

AbstractThe problem is considered of atmospheric meteorological events’ classification, such as sea breezes, fogs, and high winds, in coastal areas. In situ wind, temperature, humidity, pressure, radiance, and turbulence meteorological measurements are used as predictors. Local atmospheric events of 2013–14 were analyzed and classified manually using data of the measurement campaign in the coastal area of the English Channel in Dunkirk, France. The results of that categorization allowed the training of a few supervised classification algorithms using the data of an ultrasonic anemometer as predictors. The comparison was carried out for the K-nearest-neighbors classifier, support vector machine, and two Bayesian classifiers—quadratic discriminant analysis and Parzen–Rozenblatt window. The analysis showed that the K-nearest-neighbors and quadratic discriminant analysis classifiers reveal the best classification accuracy (up to 80% correctly classified meteorological events). The latter classifier has higher calculation speed and is less sensitive to unbalanced data and the overtraining problem. The most informative atmospheric parameters for events recognition were revealed for each algorithm. The results obtained showed that supervised classification algorithms contribute to automation of processing and analyzing of local meteorological measurements.

scholarly journals (Un)expected Similarity of the Temporary Adhesive Systems of Marine, Brackish, and Freshwater Flatworms

2021 ◽  
Vol 22 (22) ◽  
pp. 12228
Author(s):  
Philip Bertemes ◽  
Robert Pjeta ◽  
Julia Wunderer ◽  
Alexandra L. Grosbusch ◽  
Birgit Lengerer ◽  
...  
Keyword(s):  
Gene Expression ◽  
In Situ Hybridisation ◽  
Adhesive System ◽  
Wound Dressings ◽  
Freshwater Species ◽  
Freshwater Habitats ◽  
Anchor Cell ◽  
Adhesive Proteins ◽  
Related Proteins

Many free-living flatworms have evolved a temporary adhesion system, which allows them to quickly attach to and release from diverse substrates. In the marine Macrostomum lignano, the morphology of the adhesive system and the adhesion-related proteins have been characterised. However, little is known about how temporary adhesion is performed in other aquatic environments. Here, we performed a 3D reconstruction of the M. lignano adhesive organ and compared it to the morphology of five selected Macrostomum, representing two marine, one brackish, and two freshwater species. We compared the protein domains of the two adhesive proteins, as well as an anchor cell-specific intermediate filament. We analysed the gene expression of these proteins by in situ hybridisation and performed functional knockdowns with RNA interference. Remarkably, there are almost no differences in terms of morphology, protein regions, and gene expression based on marine, brackish, and freshwater habitats. This implies that glue components produced by macrostomids are conserved among species, and this set of two-component glue functions from low to high salinity. These findings could contribute to the development of novel reversible biomimetic glues that work in all wet environments and could have applications in drug delivery systems, tissue adhesives, or wound dressings.

scholarly journals Assessing Forest Governance in the Countries of the Greater Mekong Subregion

Forests ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 47 ◽  
Author(s):  
David Gritten ◽  
Sophie Lewis ◽  
Gijs Breukink ◽  
Karen Mo ◽  
Dang Thuy ◽  
...  
Keyword(s):  
Civil Society ◽  
Rural Communities ◽  
News Media ◽  
Development Program ◽  
Forest Governance ◽  
Informed Decision Making ◽  
Key Stakeholders ◽  
Challenges And Opportunities ◽  
Governance Challenges ◽  
Greater Mekong Subregion

The forest landscapes of the Greater Mekong Subregion (GMS) are changing dramatically, with a multitude of impacts from local to global levels. These changes invariably have their foundations in forest governance. The aim of this paper is to assess perceptions of key stakeholders regarding the state of forest governance in the countries of the GMS. The work is based on a quantitative and qualitative analysis of the perceptions of forest governance in the five GMS countries, involving 762 representatives from government, civil society, news media, and rural communities. The work identified many challenges to good forest governance in the countries in the region, as well as noting reasons for optimism. Generally speaking, there was a feeling that the policies, legislation, and institutional frameworks were supportive, but there are numerous challenges in terms of implementation, enforcement, and compliance. The work also presents a program of activities recommended by the research participants to address governance challenges and opportunities in the GMS countries. These include the development of a forest governance monitoring system, and initiatives that support informed decision-making by forest product consumers in the region as well as the implementation of a capacity development program for non-state actors (e.g., civil society, news media) to ensure they are more able to support the diverse, and often demanding, forest governance initiatives.

Micropolitan Areas Creating Leadership in the New Economy

2020 ◽  
Vol 2 (1) ◽  
pp. 1-18
Author(s):  
Kristin Joyce Tardif
Keyword(s):  
Economic Development ◽  
Rural Communities ◽  
Development Program ◽  
New Economy ◽  
The United States ◽  
Creative Industries ◽  
Creative Economy ◽  
Urban Centers ◽  
Major Shift ◽  
The U.S

The United States is experiencing a major shift. This started before COVID-19 spread around the planet; however, the virus has confirmed that a major shift is needed. For years, inward migration to urban centers drove our economic development, and young people moved from rural communities to urban centers in search of opportunity and income. In 2017 a paradigm shift occurred. Young professionals started moving out of urban centers and back into rural communities. They are searching for safe places to raise their families, stability, good schools, and a sense of place and community. These young bright professionals have ignited a new economy based on the creative economy. From this new economy, the U.S. Bureau of Census has created a new category called “micropolitan areas.” There are now 581 micropolitan areas in the U.S. (population greater than 10 thousand and less than 50 thousand), and many of these have developed a strong economic development program that is not based on courting large industrial business but courting small to medium creative industries.

Sign in / Sign up

Export Citation Format

Share Document