Molecular basis of Arginine and Lysine DNA sequence-dependent thermo-stability modulation

We have used a variety of theoretical and experimental techniques to study the role of four basic amino acids–Arginine, Lysine, Ornithine and L-2,4-Diaminobutyric acid–on the structure, flexibility and sequence-dependent stability of DNA. We found that the presence of organic ions stabilizes the duplexes and significantly reduces the difference in stability between AT- and GC-rich duplexes with respect to the control conditions. This suggests that these amino acids, ingredients of the primordial soup during abiogenesis, could have helped to equalize the stability of AT- and GC-rich DNA oligomers, facilitating a general non-catalysed self-replication of DNA. Experiments and simulations demonstrate that organic ions have an effect that goes beyond the general electrostatic screening, involving specific interactions along the grooves of the double helix. We conclude that organic ions, largely ignored in the DNA world, should be reconsidered as crucial structural elements far from mimics of small inorganic cations.

Stiffness-Oriented Structure Topology Optimization for Hinge-Free Compliant Mechanisms Design

This paper presents a stiffness-oriented structure topology optimization (TO) method for the design of a continuous, hinge-free compliant mechanism (CM). A synthesis formulation is developed to maximize the mechanism’s mutual potential energy (MPE) to achieve required structure flexibility while maximizing the desired stiffness to withstand the loads. Different from the general approach of maximizing the overall stiffness of the structure, the proposed approach can contribute to guiding the optimization process focus on the desired stiffness in a specified direction by weighting the related eigen-frequency of the corresponding eigenmode. The benefit from this is that we can make full use of the material in micro-level compliant mechanism designs. The single-node connected hinge issue which often happened in optimized design can be precluded by introducing the eigen-frequency constraint into this synthesis formulation. Several obtained hinge-free designs illustrate the validity and robustness of the presented method and offer an alternative method for hinge-free compliant mechanism designs.

Thermodynamics of semi-specific ligand recognition: the binding of dipeptides to the E.coli dipeptide binding protein DppA

This investigation of the temperature dependence of DppA interactions with a subset of three dipeptides (AA. AF and FA) by isothermal titration calorimetry has revealed the negative heat capacity ($$\Delta {C}_{p}^{o}$$ Δ C p o ) that is a characteristic of hydrophobic interactions. The observation of enthalpy–entropy compensation is interpreted in terms of the increased structuring of water molecules trapped in a hydrophobic environment, the enthalpic energy gain from which is automatically countered by the entropy decrease associated with consequent loss of water structure flexibility. Specificity for dipeptides stems from appropriate spacing of designated DppA aspartate and arginine residues for electrostatic interaction with the terminal amino and carboxyl groups of a dipeptide, after which the binding pocket closes to become completely isolated from the aqueous environment. Any differences in chemical reactivity of the dipeptide sidechains are thereby modulated by their occurrence in a hydrophobic environment where changes in the structural state of entrapped water molecules give rise to the phenomenon of enthalpy–entropy compensation. The consequent minimization of differences in the value of ΔG0 for all DppA–dipeptide interactions thus provides thermodynamic insight into the biological role of DppA as a transporter of all dipeptides across the periplasmic membrane.

MRI BRAIN IMAGE SEGMENTATION BY USING A DEEP SPECTRUM IMAGE TRANSLATION NETWORK

Now a days medical image processing is challenging task. Because of its structure, flexibility in place, and irregular borders, manual identification and segmentation of brain tumours is difficult. The proposed work uses the super pixel technique to identify and segment brain tumours based on transfer learning. This process is called as dense prediction because we are predicting for each pixel in the image. It is important to identify these tumours early to provide better treatment to patients. Early detection improves the patient's chances of survival. The primary goal of this study is to use deep learning to segment brain tumours in MRI images. The suggested technique is tested using data from Kaggle data sets for Brain Tumour Segmentation. In the first step we are pre-processing the required data sets, after getting required manner we are applying the data to VGG-19 transfer learning network to identify the disorder of the brain tumours. And then we are using UNet model for tumour detection process. Due to these processes, we are getting better improvement in terms of quality metrics.

Resurrecting Golgi proteins to grasp Golgi ribbon formation and self-association under stress

The Golgi complex is a membranous organelle located in the heart of the eukaryotic secretory pathway. A subfamily of the Golgi matrix proteins, called GRASPs, are key players in the stress-induced unconventional secretion, the Golgi dynamics during mitosis/apoptosis, and Golgi ribbon formation. The Golgi ribbon is vertebrate-specific and correlates with the appearance of two GRASP paralogs (GRASP55/GRASP65) and two coiled-coil Golgins (GM130/Golgin45), which interact with each other in vivo. Although essential for the Golgi ribbon formation and the increase in Golgi structural complexity, the molecular details leading to their appearance only in this subphylum are still unknown. Moreover, despite the new functionalities supported by the GRASP paralogy, little is known about the structural and evolutionary differences between these paralogues. In this context, we used ancestor sequence reconstruction and several biophysical/biochemical approaches to assess the evolution of the GRASP structure, flexibility, and how they started anchoring their Golgin partners. Our data showed that the Golgins appeared in evolution and were anchored by the single GRASP ancestor before gorasp gene duplication and divergence in Metazoans. After the gorasp divergence, variations inside the GRASP binding pocket determined which paralogue would recruit each Golgin partner (GRASP55 with Golgin45 and GRASP65 with GM130). These interactions are responsible for the protein's specific Golgi locations and the appearance of the Golgi ribbon. We also suggest that the capacity of GRASPs to form supramolecular structures is a long-standing feature, which likely affects GRASP's participation as a trigger of the stress-induced secretory pathway.

Understanding the impact of supporting conceptual information design

This article argues that supporting conceptual information design should be a priority as it will better equip design practitioners for their jobs. Findings from a longitudinal evaluation of a tool – MapCI Cards – using multiple methods to assess the impact of supporting conceptual design in professional practice are reported here. Internal and external factors emerged as having an adverse influence on information designers’ responses to conceptual design. Increased conceptual design awareness and more confident decisions resulted from working with a support tool. Structure, flexibility, and externalizations are indicated as possible ways to effectively support conceptual information design. The article ends with recommendations for future support tools.

Advancement of aliphatic polycarbonates with nanoclay addition: An overview

Aliphatic polycarbonates are considered as newly developed biodegradable polymer, which results from a sustainable copolymerization of epoxides and carbon dioxide (CO2) process. These aliphatic carbonates have weak properties in terms of thermal stability and mechanical properties, due to its carbon structure flexibility, hence causing limitation to its applications. Up to date, studies on aliphatic polycarbonates are progressively conducted to maximize its opportunity as an alternative nanocomposite. This review was carried out to provide insights on the progression in producing aliphatic polycarbonates by incorporating various type of fillers to enhance physicochemical, thermal and mechanical properties of aliphatic polycarbonates. The results revealed that a blend of aliphatic polycarbonates/clay nanocomposites with low clay content up to 10 wt.% displayed improved glass transition temperature and thermal degradation in comparison with the pure one. The improved thermal stability was due to the nanoparticle’s dispersion into matrix of aliphatic polycarbonates. The mechanical properties such as Young’s Modulus and tensile strength of aliphatic polycarbonates were also improved with addition of nanoclay. The improvement of thermal and mechanical properties of aliphatic polycarbonates at low content of nanoclay proves that the addition of nanoclay into polymer matrix is a promising technique to design the properties of aliphatic polycarbonates particularly for the coating application as water and oxygen barrier film.

Stages and methods of formation of marketing strategy of enterprises in the market of beekeeping products

The arƟcle invesƟgates the theoreƟcal foundaƟons of the markeƟng strategies of enterprises formaƟon. The main stages of formaƟon of markeƟng strategy of the enterprise in the field of beekeeping are considered, the priority methods which should be applied for its formaƟon are substanƟated. It is determined that the markeƟng strategy of the beekeeping enterprise is formed taking internal and external factors into account. The internal factors of strategy formaƟon of the enterprises of branch of beekeeping concern: organizaƟonal structure; flexibility of the management system; system of organizaƟon of markeƟng acƟvity; principles of acƟvity of managerial staff and taking into account markeƟng opportuniƟes and goals when making decisions; quality and speed of receiving informaƟon related to markeƟng acƟviƟes; formaƟon of incenƟves for markeƟng staff (or those employees who perform markeƟng funcƟons). External factors have a strong influence on the long-term goals of markeƟng acƟviƟes and are related to the current economic policy, the degree of development and development trends of internaƟonal trade, the structure of the country’s markets, changes in demographic characterisƟcs and consumer preferences. It is determined that the choice of markeƟng strategy of the enterprise of the beekeeping industry goes through stages: - analysis of the current state of the producer-enterprise of beekeeping products and market acƟvity of the enterprises of the branch; - analysis and assessment of market potenƟal; - analysis of opportuniƟes for the development of enterprises in the beekeeping industry; - analysis of economic condiƟons and the legal field; - analysis of trends in the world economy with export-oriented acƟviƟes; - selecƟon and development of a strategy with a focus on long-term development. In the context of developing a markeƟng strategy, general scienƟfic methods determine the general logic of research and precede special methods. Special research methods used in the process of forming markeƟng strategies can be divided into matrix, mathemaƟcal, staƟsƟcal, forecasƟng methods and expert methods.

Organic Electrode Materials for Non-aqueous K-Ion Batteries

The demands for high-performance and low-cost batteries make K-ion batteries (KIBs) considered as promising supplements or alternatives for Li-ion batteries (LIBs). Nevertheless, there are only a small amount of conventional inorganic electrode materials that can be used in KIBs, due to the large radius of K+ ions. Differently, organic electrode materials (OEMs) generally own sufficiently interstitial space and good structure flexibility, which can maintain superior performance in K-ion systems. Therefore, in recent years, more and more investigations have been focused on OEMs for KIBs. This review will comprehensively cover the researches on OEMs in KIBs in order to accelerate the research and development of KIBs. The reaction mechanism, electrochemical behavior, etc., of OEMs will all be summarized in detail and deeply. Emphasis is placed to overview the performance improvement strategies of OEMs and the characteristic superiority of OEMs in KIBs compared with LIBs and Na-ion batteries.