Stability Of Hybrids Research Articles

Simulation of multiple microenvironments shows a pivot role of RPTPs on the control of Epithelial-to-Mesenchymal Transition

Epithelial-to-Mesenchymal Transition (EMT) is a natural and reversible process involved in embryogenesis, wound healing and thought to participate in the process of metastasis. Multiple signals from the microenvironment have been reported to drive EMT. However, the tight control of this process on physiological scenarios and how it is disrupted during cancer progression is not fully understood. Here, we analysed a regulatory network of EMT accounting for 10 key microenvironment signals focusing on the impact of two cell contact signals on the reversibility of EMT and the stability of resulting phenotypes. The analysis showed that the microenvironment is not enough for stabilizing Hybrid and Amoeboid-like phenotypes, requiring intracellular de-regulations as reported during cancer progression. Our simulations demonstrated that RPTP activation by cell contacts have the potential to inhibit the process of EMT and trigger its reversibility under tissue growth and chronic inflammation scenarios. Simulations also showed that hypoxia inhibits the capacity of RPTPs to control EMT. Our analysis further provided a theoretical explanation for the observed correlation between hypoxia and metastasis under chronic inflammation, and predicted that de-regulations in FAT4 signalling may promote Hybrid stabilization. Taken together, we propose a natural control mechanism of EMT that supports the idea that EMT is tightly regulated by the microenvironment.

Molecular cytological analysis of alien introgressions in common wheat lines derived from the cross of TRITICUM AESTIVUM with T. kiharae

BackgroundTriticum kiharae (AtAtGGDD, 2n = 42) is of interest for the improvement of bread wheat as a source of high grain protein and gluten content, as well as resistance to many diseases. The use of T. kiharae for the improvement of T. aestivum L. is complicated by the fact that the homology degree of their genomes is low and this leads to an unbalanced set of chromosomes in the gametes of its first generations and the elimination of some genotypes. The aim of this study was to analyze the nature of alien introgressions and their effect on the cytological stability of hybrids obtained from crossing of bread wheat varieties with T. kiharae.ResultsUsing C-banding, the presence of entire chromosomes of T. kiharae in the karyotypes of hybrid lines (intergenomic substitution 2G/2B), chromosome arms (centric translocation Т2AtS:2AL) and large inserts in the form of terminal translocations involving chromosomes of 1st, 3rd and 5th homoeologous groups of B- and G-genomes were found. Molecular markers revealed short introgression of T. kiharae into the genome of common wheat varieties. The highest introgression frequency was shown for 1A, 1B, 2A, 5B, and 6A chromosomes, while no foreign chromatin was detected in 4A and 4B chromosomes. A high level of cytological stability (a meiotic index of 88.18–93.0%) was noted for the majority of introgression lines. An exception was found for the lines containing the structural reorganization of chromosome 5B, affecting the main genes of chromosome synapsis in terms of their functioning.ConclusionsDuring the stabilization of hybrid karyotypes, the introgression of genetic material from T. kiharae into the genome of T. aestivum occurs in the form of short fragments detectable only by molecular markers and in the form of whole chromosomes (intergenomic substitution) and their large fragments (centric and terminal translocations). The level of cytological stability achieved in F10 by the majority of introgression lines ensures the formation of functional gametes sufficient for the successful reproduction of the obtained hybrids.

Butterfly Methanes: Designing a Novel Class of anti-van't Hoff Carbons.

Among different possible non-classical structures, the stabilization of half-planar tetracoordinate carbon conformation is believed to be the most difficult one. Herein, we designed three types of half-planar tetracoordinate carbon compounds computationally by employing hybrid stabilization effects of substituents. The axial hydrogens of unstable half-planar methane are substituted with π-acceptor and σ-donor substituents such as -BH2 , -Li and the equatorial substituents selected are a combination of electropositive atoms (σ-donors)/electronegative atoms (σ-acceptors and π-donors). To establish the stabilization factors, we conducted a detailed study on vibrational frequency analysis, molecular orbital analysis (including Natural Bond Orbitals) and electrostatic potential (ESP) analysis of optimized molecular geometries using density functional theory.

G × E interaction studies in relation to heterosis and stability of grain yield in maize (Zea mays L.)

Interaction of homozygous inbreds and heterozygous single, three way and double crosses with environment had shown a differential response in achieving yield stability. Seven diverse maize inbreds, their 21 single crosses and 105 each of three way and double crosses obtained through diallel were evaluated for twelve characters across three diverse locations to estimate comparative stability of homozygous and heterozygous genotypes for grain yield. Contrasts in heterobeltiosis, combining ability and stability parameters in three environments and interaction effects were observed. Gain in heterobeltiosis (%) for grain yield was observed with decreased environmental quality in different hybrid classes suggesting that heterozygous hybrids are more stable due to individual buffering in single crosses and both individual and population buffering in case of three way and double crosses. Significant increase in SCA effects was observed in moderate environment at Hyderabad rather than at high yielding environment Palem. Significant G × E and Environment (linear) in all the crosses was observed for grain yield suggesting the effect of environment and its pre dominant effect on grain yield. Stability of hybrids was attributed to their superior performance over the parents in low yielding environment. Thus the potential use of selected heterozygous hybrids would allow under diverse environments is suggested to mitigate losses arising out of climate change.

Synthesis of silica chemisorbed bis(hydrogensulphato)benzene (SiO2–BHSB) as a new hybrid material and it's utility as an efficient, recyclable catalyst for the green synthesis of bis(indolyl)methanes

Synthesis of silica chemisorbed bis(hydrogensulphato)benzene (SiO2-BHSB) was achieved as a new hybrid catalytic material, its structure, stoichiometry and stability was established using modern analytical techniques such as CP-MAS 13C NMR, CP-MAS 29Si NMR, EDX, FT-IR, TGA and DTG. The synthesised material SiO2–BHSB was observed as an environmentally benign, recyclable catalyst for the synthesis of bis(indolyl)methanes (BIMs) via an electrophilic substitution reaction of indoles by aldehydes or ketones under solvent free grinding condition. A range of structurally diverse aldehydes, ketones and indoles were smoothly undergone the developed catalytic protocol to offer good to excellent yields of corresponding bis(indolyl)methane derivatives in shorter reaction times. The synthesised material SiO2–BHSB showed a sustained catalytic activity up to five cycles of its reuse for the synthesis of BIMs. The catalytic protocol offered a chemo-selective route for the synthesis of BIMs, in which aldehydes are pushed exclusively in presence of ketones to undergo the reaction. Simple working procedure, ease of isolation of the catalyst, environmentally compatible energy conditions and no side products are the additional salient features of this protocol.

Hybrid Maximum Power Point Tracking Method Based on Iterative Learning Control and Perturb & Observe Method

Maximum power point tracking (MPPT) is used to utilize intermittent solar power fully in the photovoltaic (PV) systems. Tracking the MPP fast, and accurately with changes in the solar irradiance, and the temperature is the goal of MPPT techniques. In this paper, a hybrid MPPT method based on iterative learning control (ILC), and perturb, and observe (P&O) algorithm is proposed. ILC can deal with the periodic variations to eliminate the steady-state oscillations, and errors, when the operation point is close to the MPP or a small irradiance variation occurs. In the proposed hybrid MPPT technique, a high frequency power P&O method without deadtime is used to improve the dynamic response when the irradiance changes rapidly. This paper presents the theoretical background of the hybrid MPPT algorithm, design, and stability analysis. Simulation, and hardware validation results substantiate the effectiveness of the proposed method.

Finite element modelling of hybrid stabilization systems for the human lumbar spine.

Intersomatic fusion is a very popular treatment for spinal diseases associated with intervertebral disc degeneration. The effects of three different hybrid stabilization systems on both range of motion and intradiscal pressure were investigated, as there is no consensus in the literature about the efficiency of these systems. Finite element simulations were designed to predict the variations of range of motion and intradiscal pressure from intact to implanted situations. After hybrid stabilization system implantation, L4-L5 level did not lose its motion completely, while L5-S1 had no mobility as a consequence of disc removal and fusion process. BalanC hybrid stabilization system represented higher mobility at the index level, reduced intradiscal pressure of adjacent level, but caused to increment in range of motion by 20% under axial rotation. Higher tendency by 93% to the failure was also detected under axial rotation. Dynesys hybrid stabilization system represented more restricted motion than BalanC, and negligible effects to the adjacent level. B-DYN hybrid stabilization system was the most rigid one among all three systems. It reduced intradiscal pressure and range of motion at the adjacent level except from motion under axial rotation being increased by 13%. Fracture risk of B-DYN and Dynesys Transition Optima components was low when compared with BalanC. Mobility of the adjacent level around axial direction should be taken into account in case of implantation with BalanC and B-DYN systems, as well as on the development of new designs. Having these findings in mind, it is clear that hybrid systems need to be further tested, both clinically and numerically, before being considered for common use.

Genotype-by-environment interaction and yield stability analysis of biomass sorghum hybrids using factor analytic models and environmental covariates

Abstract Biomass sorghum has emerged as an alternative crop for biofuel and bioelectricity production. Fresh biomass yield (FBY) is a quantitative trait highly correlated with the calorific power of energy sorghum cultivars, but also highly affected by the environment. The main goal of this study was to investigate the genotype-by-environment interaction (G × E) and the stability of sorghum hybrids evaluated for FBY across different locations and years, using factor analytic (FA) mixed models and environmental covariates. Pairwise genetic correlations between environments ranged from -0.21 to 0.99, indicating the existence of null to high G × E. The FA analysis unveiled that solely three factors explained more than 79% of the genetic variance, and that more than 60% of the environments were clustered in the first factor. Moderate correlations were found between some environmental covariates and the loadings of FA models for environments, suggesting the possible factors to explain the high G × E between environments clustered in a given factor. For example: precipitation, minimum temperature and speed wind were correlated to the environmental loadings of factor 1; minimum temperature, solar radiation and altitude to factor 2; and crop growth cycle to factor 3. The latent regression analysis was used to identify hybrids more responsive to a set of environments, as well as hybrids specifically adapted to a given environment. Finally, FA models can be successfully used to identify the main environmental factors affecting G × E, such as minimum temperature, precipitation, solar radiation, crop growth cycle and altitude.

Plant Yield Efficiency by Homeostasis as Selection Tool at Ultra-Low Density. A Comparative Study with Common Stability Measures in Maize

The study pertains to field experimentation testing seven maize (Zea mays L.) hybrids at four densities, across five locations under normal (NIR) and low-input (LIR) regimes. The main objective was to assess the prognostic value of plant yield efficiency by homeostasis (PYEH) for breeding purposes at ultra-low plant density to predict hybrid yield potential and stability. PYEH comprises plant yield efficiency (PYE) that reflects the ability of individual plants to exploit resources, and plant yield homeostasis (PYH) that indicates the crop’s ability to evade acquired plant-to-plant variability. The same hybrids were also evaluated for stability by commonly used parametric and non-parametric statistics based on data at low (LCD) and high crop densities (HCD). Hybrid stability focused on potential yield loss due to erratic optimum density (OD). Most methods produced conflicting results regarding hybrid ranking for yield and stability especially at LCD. In contrast, PYEH consistently highlighted high-yielding and stable hybrids, potentially able to reach the attainable crop yield (ACY) inter-seasonally irrespective of crop spacing. Low density is common practice under resource-deficit conditions, so crop adaptation to crop spacing is a viable option to overcome erratic OD that constitutes a root source of crop instability in rainfed maize. The results were further supportive of breeding at ultra-low density to facilitate the identification and selection of superior genotypes, since such conditions promote phenotypic expression and differentiation, and ensure repeatability across diverse environments.

Adaptability and stability evaluation of maize hybrids using Bayesian segmented regression models.

The occurrence of genotype by environment interaction (G x E), which is defined as the differential response of genotypes to environmental variation, is frequently reported in maize cultures, making it challenging to recommend cultivars. Methods allowing to study the potential nonlinear pattern of genotype responses to environmental variation allied to prior beliefs on unknown parameters are interesting to evaluate the phenotypic adaptability and stability of genotypes. In this context, the present study aimed to assess the adaptability and stability of maize hybrids, by using the Bayesian segmented regression model, and evaluate the efficacy of using informative and minimally informative prior distributions for the selection of cultivars. Randomized complete-block design experiments were carried out to study the yield (kg/ha) of 25 maize hybrids, in 22 different environments, in Northeastern Brazil. The Bayesian segmented regression model fitted using informative prior distributions presented lower credibility intervals and Deviance Criterium of Information values, compared to those obtained by fitting using minimally informative distributions. Therefore, the model using informative prior distributions was considered for the adaptability and stability evaluation of maize genotypes. Once most northeastern farmers in Brazil have limited capital, the genotype P4285HX should be considered for planting, due to its high yield performance and adaptability to unfavorable environments.

Agronomic attributes and stability of exotic sunflower hybrids in Iran

Abstract In order to identifying of high yielding compatible sunflower hybrids for different regions of Iran, a set of 10 exotic hybrids from Serbia, Turkey, and Italy and four Iranian hybrids were evaluated for agronomic traits; days to flowering and maturity, plant height, head and stem diameter, 1000-achenes weight, achene number per head, oil content and achene, and oil yield. The experiments were conducted as completely randomized block design with four replications in Alborz, Mazandaran, Khuzestan, and West Azerbaijan Provinces for two years (2017–2018). According to the results growing period of the hybrids were variable from 86 days for Dukat to 98 days for Fantaziya. The hybrids Slatki and Dukat had the highest (70 g) and lowest (56 g) 1000-achenes weight. The highest oil content was observed in 08TR003 (45.6%). Among the locations, Miandoab had the highest achene yield (3110 kg/ha). In Sari; the hybrids Barzegar, Fantaziya, and Slatki (3080, 2893, and 2853 kg/ha respectively), In Dezful; Barzegar, Cartago, and Oscar (3234, 3409, and 3226 kg/ha respectively), in Karaj; Oscar, Shams, and Fantaziya (3138, 3081, and 3050 kg/ha respectively), and in Miandob Shams, Fantaziya, and Slatki (4093, 4038, and 3895 kg/ha respectively) had the highest achene yield. Considering overall mean Fantaziya, Shams, and Oskar had the highest achene yield (3286, 3145, and 3087 kg/ha respectively), as well as Fantaziya followed by Barzegar and Shams had the highest oil yield (1396, 1335, and 1330 kg/ha respectively). Considering phenotypic variability among the exotic hybrids Fantaziya, Oskar, Slatki, Novak, 08TR003, and Meteor with lower coefficient of variation and higher achene yield considered as the stable higher yielding hybrids in four test locations of Iran. Through identifying high-yielding and compatible hybrids, the results of this study can assists in increasing of sunflower yield and production in Iran.

Competition over resources optimized fuzzy TIDF controller for frequency stabilization of hybrid micro‐grid system

Competition over resources optimized fuzzy TIDF controller for frequency stabilization of hybrid micro‐grid system

IMPACT OF CUCUMBER GENOTYPE ON THE DAMAGES CAUSED BY TWOSPOTTED SPIDER MITE AND EFFICIENCY OF BIOLOGICAL SPECIMENS

Due to the growing variety of vegetables, the impact of genotypic parameters of plants on pest resistance and efficiency of biological specimens is of high importance when selecting and creating new varieties and hybrids. The researchers found out the significant differences in stability of parental forms, hybrids and cucumber varieties of the Siberian selection in relation to twospotted spider mite. The paper finds out relatively resistant parental forms - ZhL-4 and GP-61/b, and also samples of the paternal form - GF-7 and a maternal line - ZhL-9 damaged by a phytophage in a strong degree have been defined rather steady against a phytophage. High acaricidal effect of Phytoverm was found on all studied varietal samples, however the most effective biospecimen restrained development of the pest on plants of relatively resistant to phytophage of female line ZL-4. Reproduction of the twospotted spider phytoseiulus did not depend on genotypic features of parental forms, varieties and hybrids of cucumbers. The number of acarifages increased by 7.8-8.2 times in two weeks after appearance on the plants inhabited by spider mite in comparison with the initial number, as a result of which the damage rate of plants by the pest of most cultivars decreased, and in male forms practically did not change (GF-19) or slightly increased (GF-7). According to biochemical parameters, cucumber varieties with different degree of resistance to phytophage differed in dry matter content. Non-resistant to twospotted spider mite female forms LL-9, LL-12/1 and Nadezhda variety contained the lowest concentration of dry matter (5.4%), the highest amount of dry matter was observed in female line LL-4, which has the highest pest resistance (6.0%). Since the inherited traits are predominantly transmitted by the maternal component and the paternal form enhances these properties, it is important to assess not only the yield and flavour qualities but also the degree of resistance of parental forms to pests when selecting cucumber varieties and hybrids.

Improved nearest-neighbor parameters for the stability of RNA/DNA hybrids under a physiological condition.

The stability of Watson–Crick paired RNA/DNA hybrids is important for designing optimal oligonucleotides for ASO (Antisense Oligonucleotide) and CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)–Cas9 techniques. Previous nearest-neighbour (NN) parameters for predicting hybrid stability in a 1 M NaCl solution, however, may not be applicable for predicting stability at salt concentrations closer to physiological condition (e.g. ∼100 mM Na+ or K+ in the presence or absence of Mg2+). Herein, we report measured thermodynamic parameters of 38 RNA/DNA hybrids at 100 mM NaCl and derive new NN parameters to predict duplex stability. Predicted ΔG°37 and Tm values based on the established NN parameters agreed well with the measured values with 2.9% and 1.1°C deviations, respectively. The new results can also be used to make precise predictions for duplexes formed in 100 mM KCl or 100 mM NaCl in the presence of 1 mM Mg2+, which can mimic an intracellular and extracellular salt condition, respectively. Comparisons of the predicted thermodynamic parameters with published data using ASO and CRISPR–Cas9 may allow designing shorter oligonucleotides for these techniques that will diminish the probability of non-specific binding and also improve the efficiency of target gene regulation.

Оценка экологической пластичности и стабильности сортов и гибридов рапса ярового

Оценка экологической пластичности и стабильности сортов и гибридов рапса ярового

Biomechanical investigation of the effect of pedicle-based hybrid stabilization constructs: A finite element study.

Hybrid stabilization is widely performed for the surgical treatment of degenerative disk diseases. Pedicle-based hybrid stabilization intends to reduce fusion-associated drawbacks of adjacent segment degeneration, construct failure, and pseudoarthrosis. Recently, many types of pedicle-based hybrid stabilization systems have been developed and optimized, using polymeric devices as an adjunct for lumbar fusion procedures. Therefore, the purpose of this study was to evaluate the effect of new pedicle-based hybrid stabilization on bending stiffness and center of rotation at operated and adjacent levels in comparison with established semirigid and rigid devices in lumbar fusion procedures. A validated three-dimensional finite element model of the L3-S1 segments was modified to simulate postoperative changes during combined loading (moment of 7.5 N m + follower load of 400 N). Two models instrumented with pedicle-based hybrid stabilization (Dynesys Transition Optima, NFlex), semirigid system (polyetheretherketone), and rigid fixation system (titanium rod (Ti) were compared with those of the healthy and degenerated models. Contact force on the facet joint during extension increased in fusion (40 N) with an increase of bending stiffness in Dynesys and NFlex. The center of rotation shifted in posterior and cranial directions of the fused level. The centers of rotation in the lower lumbar spine is segment dependent and altered with the adopted construct. The bending stiffness was varied from 1.47 N m/° in lateral bending for the healthy model to 5.75 N m/° for the NFlex stabilization, which had the closest center of rotation, compared to the healthy center of rotation. Locations of center of rotation, stress, and strain distribution varied according to construct design and materials used. These data could help understand the biomechanical effects of current pedicle-based hybrid stabilization on the behavior of the lower lumbar spine.

Three-dimensional Porous Graphene/Polyaniline Hybrids for High Performance Supercapacitor Electrodes

Graphene-based composites took extensive attraction as electrodes for supercacitors these years. Three-dimensional cross-linking porous graphene (3D rGO-m) was obtained by KOH activation to graphene modified by 1,2,4-triaminobenzene. 3D porous graphene/ polyaniline hybrids (3D rGO-m/PANI) was prepared by the in-situ chemical oxidative polymerization. The rGO-m are reconstructed from 2D to 3D porous structure after KOH activation. The PANI nanorod arrays are successfully decorated on the surface of the 3D porous graphene sheets. The specific capacitance of the 3D rGO-m/PANI hybrids reach 985 F/g at 0.5 A/g. The capacitance retention of 3D rGO-m/PANI maintains 90% of its initial capacity after 1000 cycles, while rGO-m/PANI only keeps 83% of its initial capacity, the cycling stability of both hybrids are higher than that of pure PANI (69%).

Chirality-pure carbon nanotubes show distinct complexation with recognition DNA sequences

Pure-chirality single-wall carbon nanotubes (SWCNTs) that are non-covalently complexed with recognition DNA sequences exhibit unique interaction behavior and hybrid stability in aqueous environments. The complexation of DNA-wrapped SWCNTs was found to be a strong function of both the DNA sequence and SWCNT chiral structure, highlighted by the distinct coating displacement of the same recognition DNA sequence from a pair of (6,5) enantiomers by a strong surfactant. A broad range of changes were observed for different DNA/SWCNT recognition pairs with surfactant exchange including the increase in nanotube photoluminescence intensity in the near-infrared (NIR) from 1.3 to 14.7-fold and time constants deduced from DNA displacement kinetics ranging from 9 s to 230 s. A large time constant of 230 s and a relatively small 4.4-fold increase in NIR emission intensity were obtained for the CTC3TC-(7,6) hybrid highlighting the vast potential of short DNA sequences for improved nanotube sorting and hybrid stability in aqueous environments. Additionally, CTC3TC-(7,6) was identified as the only hybrid to exhibit an increase in NIR fluorescence intensity in serum-containing cell culture media among all samples tested. Our results demonstrated unique optical properties and hybrid stability of DNA/SWCNT recognition pairs, providing a foundation for developing applications of chirality-pure SWCNTs.

A new hybrid stability measure for feature selection

Feature Selection (FS) algorithms are applied in bioinformatics applications to identify the disease causing genes. Performance of such algorithms is measured in terms of accuracy of the model and stability of FS algorithms. Stability evaluates the identical replication of feature sets obtained after every execution. Recently research has shown that a stability measure must satisfy set of properties like, fully defined, monotonicity, boundedness, deterministic maximum stability, and correction for chance. Among the existing stability measures, only Nogueira’s frequency based stability measure satisfies all the required properties. However, frequency based stability measures fail to discriminate among the cases when overall frequency of features are same. In order to address this issue, the paper proposes a hybrid similarity based stability measure which satisfies all the desirable properties, as mentioned earlier. The proposed stability measure is unique as it is the first similarity based stability measure that satisfies all the required properties. Also, all these essential properties are mathematically established. Further, the paper also proposes a combination of frequency based and similarity based measure which preserves all the aspects of both the approaches. The work presented also analyzes the stability performance of LASSO and Elastic Net, using synthetic and microarray gene expression datasets. Elastic Net depicts higher stability and selection of relevant features.

Nano-delivery systems based on carvacrol prodrugs and fibrous clays

The fibrous silicates, Palygorskite and Sepiolite, were investigated as low-cost nanocarriers for three carvacrol prodrugs to ameliorate their pharmacokinetic and biopharmaceutic profiles. Adsorption equilibrium studies were performed in order to obtain a drug-clay hybrid system.These hybrid systems were characterized by thermal analysis, X-ray diffraction, and Fourier transform infrared spectroscopy, to study the degree and kind of interactions between the organic and inorganic components. In vitro release and chemical stability of prodrug-clay hybrids were studied in physiological gastrointestinal simulated fluids. The results showed an improvement of the chemical stability of prodrugs in hybrids systems, as well as a sustained release and a retained bioconversion of the prodrugs into the pharmacologically active carvacrol, to improve the antimicrobial activity.