A Modification of Newton–Raphson Power Flow for Using in LV Distribution System

The Newton–Raphson (NR) method is still frequently applied for computing load flow (LF) due to its precision and quadratic convergence properties. To compute LF in a low voltage distribution system (LVDS) with unbalanced topologies, each branch model in the LVDS can be simplified by defining the neutral and ground voltages as zero and then using Kron’s reduction to transform into a 3 × 3 branch matrix, but this decreases accuracy. Therefore, this paper proposes a modified branch model that is also reduced into a 3 × 3 matrix but is derived from the impedances of the phase-A, -B, -C, neutral, and ground conductors together with the grounding resistances, thereby increasing the accuracy. Moreover, this paper proposes improved LF equations for unbalanced LVDS with both PQ and PV nodes. The improved LF equations are based on the polar-form power injection approach. The simulation results show the effectiveness of the modified branch model and the improved LF equations.

Comparative and Phylogenetic Analysis of the Complete Chloroplast Genome of Santalum (Santalaceae)

Santalum (Santalaceae, sandalwood) is a hemiparasitic genus that includes approximately 15 extant species. It is known for its aromatic heartwood oil, which is used in incense and perfume. Demand for sandalwood-based products has led to drastic over-harvesting, and wild Santalum populations are now threatened. Knowledge of phylogenetic relationships will be critical for the conservation and proper management of this genus. Here, we sequenced the chloroplast genome of 11 Santalum species. The data were then used to investigate chloroplast genome evolutionary dynamics and relationships and divergence time within Santalum and related species. The Santalum chloroplast genome contains typical quadripartite structures, ranging from 143,291 to 144,263 bp. The chloroplast genome contains 110 unique genes. The whole set of ndh genes and the infA gene were found to lose their functions. The P-distance among the Santalum species was 0.0003 to 0.00828. Three mutation hotspot regions, 14 small inversions, and 460 indels events were discovered in the Santalum chloroplast genome. Branch-model-based selection analyses showed that the Santalum species were under widespread purifying selection. Our phylogenomic assessment provides an improved resolution to the phylogenetic relationships of Santalum compared to the past analyses. Our divergence time analysis showed that the crown age of Santalum was 8.46 Mya (million years ago), the first divergence occurred around 6.97 Mya, and diversification was completed approximately 1 Mya. By sequencing the 11 Santalum species chloroplast genomes, we identified the variations in the Santalum chloroplast genomes. Using the chloroplast genome sequences, phylogeny and divergence time analyses discovered that the Santalum species were likely to originate due to radiation evolution, and most speciation events occurred less than 1 Mya.

Comparative Chloroplast Genomes of Zosteraceae Species Provide Adaptive Evolution Insights Into Seagrass

Seagrasses are marine flowering plants found in tropical and sub-tropical areas that live in coastal regions between the sea and land. All seagrass species evolved from terrestrial monocotyledons, providing the opportunity to study plant adaptation to sea environments. Here, we sequenced the chloroplast genomes (cpGenomes) of three Zostera species, then analyzed and compared their cpGenome structures and sequence variations. We also performed a phylogenetic analysis using published seagrass chloroplasts and calculated the selection pressure of 17 species within seagrasses and nine terrestrial monocotyledons, as well as estimated the number of shared genes of eight seagrasses. The cpGenomes of Zosteraceae species ranged in size from 143,877 bp (Zostera marina) to 152,726 bp (Phyllospadix iwatensis), which were conserved and displayed similar structures and gene orders. Additionally, we found 17 variable hotspot regions as candidate DNA barcodes for Zosteraceae species, which will be helpful for studying the phylogenetic relationships and interspecies differences between seagrass species. Interestingly, nine genes had positive selection sites, including two ATP subunit genes (atpA and atpF), two ribosome subunit genes (rps4 and rpl20), two DNA-dependent RNA polymerase genes (rpoC1 and rpoC2), as well as accD, clpP, and ycf2. These gene regions may have played key roles in the seagrass adaptation to diverse environments. The Branch model analysis showed that seagrasses had a higher rate of evolution than terrestrial monocotyledons, suggesting that seagrasses experienced greater environmental pressure. Moreover, a branch-site model identified positively selected sites (PSSs) in ccsA, suggesting their involvement in the adaptation to sea environments. These findings are valuable for further investigations on Zosteraceae cpGenomes and will serve as an excellent resource for future studies on seagrass adaptation to sea environments.

Genomic evidence of adaptive evolution in the reptilian SOCS gene family

The suppressor of the cytokine signaling (SOCS) family of proteins play an essential role in inhibiting cytokine receptor signaling by regulating immune signal pathways. Although SOCS gene functions have been examined extensively, no comprehensive study has been performed on this gene family’s molecular evolution in reptiles. In this study, we identified eight canonical SOCS genes using recently-published reptilian genomes. We used phylogenetic analysis to determine that the SOCS genes had highly conserved evolutionary dynamics that we classified into two types. We identified positive SOCS4 selection signals in whole reptile lineages and SOCS2 selection signals in the crocodilian lineage. Selective pressure analyses using the branch model and Z-test revealed that these genes were under different negative selection pressures compared to reptile lineages. We also concluded that the nature of selection pressure varies across different reptile lineages on SOCS3, and the crocodilian lineage has experienced rapid evolution. Our results may provide a theoretical foundation for further analyses of reptilian SOCS genes’ functional and molecular mechanisms, as well as their roles in reptile growth and development.

QEPro: An ability measure of emotional intelligence for managers in a French cultural environment

Managers’ interest in the concept of emotional intelligence (EI) has grown steadily due to an accumulation of published articles and books touting EI’s benefits. For over thirty years, many researchers have used or designed tools for measuring EI, most of which raise important psychometric, cultural and contextual issues. The aim of this article is to address some of the main limitations observed in previous studies of EI. By developing and validating QEPro we propose a new performance-based measure of EI based on a modified version of Mayer and Salovey’s (1997) four-branch model. QEPro is an ability EI measure specifically dedicated to managers and business executives in a French cultural environment (N = 1035 managers and executives). In order to increase both the ecological and the face validity of the test for the target population we used the Situational Judgment Tests framework and a theory-based item development and scoring approach. For all items, correct and incorrect response options were developed using established theories from the emotion and management fields. Our study showed that QEPro has good psychometric qualities such as high measurement precision and internal consistency, an appropriate level of difficulty and a clear factorial structure. The tool also correlates in meaningful and theoretically congruent ways with general intelligence, Trait EI measures, the Big Five factors of personality, and the Affect measures used in this study. For all these reasons, QEPro is a promising tool for studying the role of EI competencies in managerial outcomes.

Patterns of Natural Selection on Mitochondrial Protein-Coding Genes in Lungless Salamanders: Relaxed Purifying Selection and Presence of Positively Selected Codon Sites in the Family Plethodontidae

There are two distinct lungless groups in caudate amphibians (salamanders and newts) (the family Plethodontidae and the genus Onychodactylus, from the family Hynobiidae). Lunglessness is considered to have evolved in response to environmental and/or ecological adaptation with respect to oxygen requirements. We performed selection analyses on lungless salamanders to elucidate the selective patterns of mitochondrial protein-coding genes associated with lunglessness. The branch model and RELAX analyses revealed the occurrence of relaxed selection (an increase of the dN/dS ratio = ω value) in most mitochondrial protein-coding genes of plethodontid salamander branches but not in those of Onychodactylus. Additional branch model and RELAX analyses indicated that direct-developing plethodontids showed the relaxed pattern for most mitochondrial genes, although metamorphosing plethodontids had fewer relaxed genes. Furthermore, aBSREL analysis detected positively selected codons in three plethodontid branches but not in Onychodactylus. One of these three branches corresponded to the most recent common ancestor, and the others corresponded with the most recent common ancestors of direct-developing branches within Hemidactyliinae. The positive selection of mitochondrial protein-coding genes in Plethodontidae is probably associated with the evolution of direct development.