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Abstract Background The three-dimensional structure of a protein can be described as a graph where nodes represent residues and the strength of non-covalent interactions between them are edges. These protein contact networks can be separated into long and short-range interactions networks depending on the positions of amino acids in primary structure. Long-range interactions play a distinct role in determining the tertiary structure of a protein while short-range interactions could largely contribute to the secondary structure formations. In addition, physico chemical properties and the linear arrangement of amino acids of the primary structure of a protein determines its three dimensional structure. Here, we present an extensive analysis of protein contact subnetworks based on the London van der Waals interactions of amino acids at different length scales. We further subdivided those networks in hydrophobic, hydrophilic and charged residues networks and have tried to correlate their influence in the overall topology and organization of a protein. Results The largest connected component (LCC) of long (LRN)-, short (SRN)- and all-range (ARN) networks within proteins exhibit a transition behaviour when plotted against different interaction strengths of edges among amino acid nodes. While short-range networks having chain like structures exhibit highly cooperative transition; long- and all-range networks, which are more similar to each other, have non-chain like structures and show less cooperativity. Further, the hydrophobic residues subnetworks in long- and all-range networks have similar transition behaviours with all residues all-range networks, but the hydrophilic and charged residues networks don’t. While the nature of transitions of LCC’s sizes is same in SRNs for thermophiles and mesophiles, there exists a clear difference in LRNs. The presence of larger size of interconnected long-range interactions in thermophiles than mesophiles, even at higher interaction strength between amino acids, give extra stability to the tertiary structure of the thermophiles. All the subnetworks at different length scales (ARNs, LRNs and SRNs) show assortativity mixing property of their participating amino acids. While there exists a significant higher percentage of hydrophobic subclusters over others in ARNs and LRNs; we do not find the assortative mixing behaviour of any the subclusters in SRNs. The clustering coefficient of hydrophobic subclusters in long-range network is the highest among types of subnetworks. There exist highly cliquish hydrophobic nodes followed by charged nodes in LRNs and ARNs; on the other hand, we observe the highest dominance of charged residues cliques in short-range networks. Studies on the perimeter of the cliques also show higher occurrences of hydrophobic and charged residues’ cliques. Conclusions The simple framework of protein contact networks and their subnetworks based on London van der Waals force is able to capture several known properties of protein structure as well as can unravel several new features. The thermophiles do not only have the higher number of long-range interactions; they also have larger cluster of connected residues at higher interaction strengths among amino acids, than their mesophilic counterparts. It can reestablish the significant role of long-range hydrophobic clusters in protein folding and stabilization; at the same time, it shed light on the higher communication ability of hydrophobic subnetworks over the others. The results give an indication of the controlling role of hydrophobic subclusters in determining protein’s folding rate. The occurrences of higher perimeters of hydrophobic and charged cliques imply the role of charged residues as well as hydrophobic residues in stabilizing the distant part of primary structure of a protein through London van der Waals interaction.

Currently, there are many uses of metal complexes, especially in the fields of medicinal chemistry and catalysis. Thus, fabrication of new complexes which perform as a catalyst and chemotherapeutic drug is always a beneficial addition to the literature. Herein, we report three heterocyclic thiosemicarbazone-based Pd(II) complexes [Pd(HL1)Cl] (C1), [Pd(L2)(PPh3)] (C2) and [Pd(L3)(PPh3)]Cl (C3) having coligands Cl and PPh3. Thiosemicarbazone ligands (H2L1, H2L2 and HL3) and the complexes (C1–C3) were characterized methodically using several spectroscopic techniques. Single-crystal X-ray diffraction methods reveal that the structural environment around the metal center of C2 is square planar, while for C1 and C3 it is a slighty distorted square plane. The supramolecular network of compounds was built via hydrogen bonds, C–H⋯π and π⋯π interactions. Density functional theory (DFT) study of the structure of the complexes supports experimental findings. The application of these complexes as catalysts toward Suzuki–Miyaura coupling reactions has been examined with various aryl halides and phenyl boronic acid in PEG 400 solvent. The complexes displayed good biomolecular interactions with DNA/protein, with a binding constant value of the order of 105 M−1. C3 showed greater binding efficacy toward these biomolecules than the other complexes, which might be due to the cationic nature of C3. Furthermore, antitumor activity of the complexes was studied against the human triple-negative breast cancer (TNBC) cell line MDA-MB-231. It was found that C3 was more toxic (IC50 = 10 ± 2.90 μM) toward MDA-MB-231 cells than the other complexes. A known chemotherapeutic drug, 5-fluorouracil, was included as positive control. The programmed cell death mechanism of C3 was confirmed. Additionally, complex-induced apoptosis was confirmed and occurred via a mitochondria-dependent (intrinsic) pathway. [ABSTRACT FROM AUTHOR]

In recent times, the global pandemic has significantly changed consumers' shopping interest, budget, shopping preference relating to formats and buying patterns. India's branded agri-food sector also witnessed a healthy upswing during the pandemic, boosted by factors like health-consciousness and lockdown restrictions driving purchases both from online and offline formats. The paper analyzes the characteristics impacting consumer choice, segmentation of consumer market and customer profiling. Quota sampling was used to judge and select subjects. A structured questionnaire was used to collect data from the Presidency division of West Bengal. Exploratory factor analysis was conducted to identify the major psychological behavioral constructs. Cluster analysis was used to split the actual market into smaller groups to concentrate on customer behavioral trends in the segments in order to better understand the different types of customers and their psychographic characteristics. The findings reveal search for information, value, product attributes and health as the factors influencing purchase intention, and in-store communication, value for money, discount offers, availability of branded products and health-consciousness as the major parameters defining consumer behavioral perceptions. [ABSTRACT FROM AUTHOR]

Coastal Foot fishing (CFF), an undervalued fishery, is practiced by marginal communities in near-shore shallow ecosystems, such as lagoons, mangroves, estuaries, wetlands etc., with low investments and expenditures. Owing to its intrinsic methodological advantage as a nature-based enterprise, CFF provides major scope for the use of indigenous and traditional knowledge. The present investigation details the scope of CFF in India as a "feedback optimization mechanism" of coastal zone sustainability. Salient features and relevance of CFF for the targets of sustainable development goals #1 (no poverty), #2 (zero hunger), #5 (gender equality), #8 (decent work and economic growth), #12 (responsible consumption and production), as well as #14 (life below water) are illustrated. Optimization of operational CFF with motorized crafts is presented highlighting its link with India's developmental programmes like Aspirational Districts, Mahatma Gandhi National Rural Employment Guarantee Scheme, Circular economy initiatives, disaster management, climate change mitigation for the coastal fishing sector. [ABSTRACT FROM AUTHOR]