A phylogeny analysis on six mullet species (Teleosti: Mugillidae) using PCR-sequencing method

In this study, genetic differences and phylogenic relationships among six Mugillidae species (Mugil cephalus, M. capito, Liza subviridis, L. saliens, L. aurata, Valamugil buchanani) were determined using PCR-sequencing. M. cephalus, L. subviridis, and V. buchanani from the Persian Gulf and Oman Sea, and L. aurata and L. saliens from the Caspian Sea were collected. Samples of an imported, Egyptian species M. capito were obtained from the Gomishan Research Center in Gorgan. Total DNA from the samples were extracted according to phenol-chloroform procedure. The extracted total DNAs were amplified using polymerase chain reaction (PCR) and then sequenced. The number of bases in the mitochondrial 16s rRNA genome used in this study approximated 600 base pairs. The size of the bands was identical in all the studied species and no heteroplasmia was observed. In addition, the numbers of variable, preserved, and Pi sites were about 114/624, 488/624, and 110/624, respectively. Analysis of the sequences showed great differences between Mugil species and the other studied species. The phylogenetic tree obtained through Neighbor-Joining method revealed that L. saliens and L. aurata were in the same branch while L. subviridis was in a separate branch. In contrast, Maximum Parsimony tree located L. subviridis and L. aurata in a single branch and assigned L. saliens to a distinct branch. This result brings in the question of monophyletic origin of the genus Liza

Influence of heat input on microstructure and mechanical properties of gas tungsten arc welded HSLA S500MC steel joints

High-strength low alloy (HSLA) S500MC steel is widely used for chassis components, structural parts, and pressure vessels. In this study, the effects of heat input during automatic gas tungsten arc welding (GTAW) on microstructure and mechanical properties of thermomechanically controlled processed (TMP) S500MC steel were investigated. A butt joint configuration was used, and welding was performed in autogenous mode. Six different levels of heat input namely 1.764 kJ/mm, 1.995 kJ/mm, 2.035 kJ/mm, 2.132 kJ/mm, 2.229 kJ/mm, and 2.33 kJ/mm were considered. Microstructural investigations revealed a different microstructure than base metal in the fusion zone (FZ) of all welded joints which was most likely due to a lath martensitic microstructure surrounded by retained austenite. With increased heat input, the amount of retained austenite and the size of packets increased. In the heat-affected zone (HAZ), two distinct regions of coarse grain (CG-HAZ) and fine grain (FG-HAZ) were observed. Due to the presence of carbides in the HAZ, mostly a martensitic microstructure with smaller packets, compared to FZ, was formed. By increasing the heat input and through the dissolution of carbides, the dimension of packets increased. Due to microstructural changes and grain growth, in both the FZ and the HAZ, the mechanical properties produced by TMP were lost in these regions. However, failure occurred in the base metal of all samples with a maximum tensile strength of 690 MPa. Thus, tensile strength in the weld zone and HAZ were higher than the base metal even for the highest heat input indicating the formation of a good joint between S500MC plates with GTAW, regardless of heat input

Effects of material properties on mechanical performance of Nitinol stent designed for femoral artery: Finite element analysis

AbstractThe Finite element method was used for evaluation of the effects of material properties on the mechanical performance of the new geometry designed for the Z-shaped open-cell femoral artery self-expanding stent, made of Nitinol wire, by application of crushing force. The behavior of the stents, having two sets of properties, was compared. The stents with higher Af temperature show better clinical behavior due to lower chronic outward force, higher radial resistive strength and more suitable superelastic behavior. Model calculations show that a large change of Af temperature could exert a substantial effect on the practical performance of the stent

Effect of Mg and Si on intermetallic formation and fracture behavior of pure aluminum-galvanized carbon-steel joints made by weld-brazing

Commercial pure aluminum and galvanized carbon steel were lap-welded using the weld-brazing (WB) technique. Three types of aluminum filler materials (4043, 4047, and 5356) were used for WB. The joint strength and intermetallic compounds at the interface of three series of samples were analyzed and compared. Depending on the Si content, a variety of ternary Al-Fe-Si intermetallic compounds (IMCs) such as Fe4(Al,Si)13, Fe2Al8Si(τ5) , and Fe2Al9Si2 (τ6) were formed at the interface. Mg element in 5356 filler material cannot contribute to the formation of Al-Fe intermetallic phases due to the positive mixing enthalpy of Mg-Fe. The presence of Mg enhances the hot cracking phenomenon near the Al-Fe intermetallic compound at the interface. Zn coating does not participate in intermetallic formation due to its evaporation during WB. It was concluded that the softening of the base metal in the heat-affected zone rather than the IMCs determines the joint efficiency.info:eu-repo/semantics/publishedVersio

Automatic frequency-based feature selection using discrete weighted evolution strategy

High dimensional datasets usually suffer from curse of dimensionality which may increase the classification time and decrease the classification accuracy beyond a certain dimensionality. Thus, feature selection is used to discard redundant features for improving classification. Nonetheless, there is not a single feature selection method which could deal with all datasets. Thus, this paper proposes an automatic hybrid feature selection incorporating both filter and wrapper methods called Extended Mutual Congestion-Discrete Weighted Evolution Strategy (EMC-DWES). First, Extended Mutual Con-gestion (EMC) is proposed as a frequency-based filter ranker to discard irrelevant and redundant features using intrinsic statistics of features. Second, Discrete Weighted Evolution Strategy (DWES) is applied on the remaining features selected by EMC to perform the final automatic feature selection within a wrapper method. DWES clusters the features and applies mutation both to select the most relevant feature in each cluster at a time and to avoid selecting redundant features simultaneously through assigning greater weights to most informative clusters. The performance of EMC-DWES (in maximizing classification accuracy and minimizing the selected subset length) is investigated using benchmark high dimensional medical datasets including Covid-19. Likewise, the superiority of EMC-DWES in comparison with state-of-the-art is also evaluated in all datasets. The implementation of EMC-DWES is available on https://github.com/KhaosResearch/EMC-DWES.(c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Tabrizicola aquatica gen. nov. sp. nov., a novel alphaproteobacterium isolated from Qurugöl Lake nearby Tabriz city, Iran

A novel Gram-negative, aerobic, non-motile and rod-shaped bacterium was isolated from Qurugöl Lake near Tabriz city. The bacterium grew chemoorganolheterotrophically and chemolithoautotrophically. However, photo-organoheterotrophic, photo-lithoautotrophic and fermentative growth could not be demonstrated. The presence of photosynthesis genes pufL and pufM was not shown and photosynthesis pigments were not formed. Strain RCRI19T grew without NaCl and tolerated up to 3 % NaCl. Growth occurred at pH 6–9 (optimum, pH 7) and 15–55 °C (optimum 40–45 °C). Vitamins were not required for growth. The major fatty acids are C18:1 ω7C, 11-methyl C18:1 ω7C, C18:0 3-OH. The predominant respiratory quinone is ubiquinone Q-10. The G+C content of genomic DNA is 65.9 mol%. Analysis of 16S rRNA sequences showed that strain RCRI19T has the highest similarities with uncultured environmental sequences followed by members of the genera Rhodobacter (≤95.75 %), Haematobacter (≤95.53 %), Gemmobacter (≤95.17 %) and Falsirhodobacter (94.60 %) in the family Rhodobacteraceae. DNA–DNA relatedness between strain RCRI19T and the closest phylogenetically related strain, Rhodobacter blasticus LMG 4305T, was 20 %. Based on its phenotypic and chemotaxonomic characteristics and considering that it does not form photosynthetic pigments and is unable to grow phototrophically, it is concluded that strain RCRI19T cannot be included into the genus Rhodobacter and any of the other related genera. Therefore, we propose to place the new bacterium into a new genus and species for which the name Tabrizicola aquatica gen. nov. and sp. nov. is proposed. The type strain is RCRI19T (=BCCM/LMG 25773T = JCM 17277T = KCTC 23724T)