Strong Physical Interaction Research Articles

Unveiling the P-solubilizing potential of bacteria enriched from natural colonies of Red Sea Trichodesmium spp.

Phosphorus (P) is pivotal for all organisms, yet its availability is, particularly in the marine habitat, limited. Natural, puff-shaped colonies of Trichodesmium, a genus of diazotrophic cyanobacteria abundant in the Red Sea, have been demonstrated to capture and centre dust particles. While this particle mining strategy is considered to help evade nutrient limitation, details behind the mechanism remain elusive. This study explores P-solubilizing bacteria (PSB) residing within Trichodesmium's associated microbial community, their potential contribution to the host, and the possible implications for P cycling in marine ecosystems. Bacterial enrichment on YBCII medium resulted in 28 enrichment cultures, primarily comprising bacterial families such as Rhodobacteraceae, Alteromonadaceae and Burkholderiaceae. Five enrichment cultures were further grown on hydroxyapatite, revealing their ability to consume and release Nitrogen and P while forming strong physical interactions with the mineral. A drop in pH was observed, indicating acid production as the primary P-solubilizing pathway. Co-cultivation experiments confirmed a positive effect on Trichodesmium erythraeum strain IMS101 growth by the presence of putative PSBs. These results reveal that the enriched bacteria exhibit significant P-solubilizing activity, thus potentially increasing the bioavailability of P in seawater. Thus, PSB could play a vital role in maintaining the P balance in the Red Sea, supporting the growth of Trichodesmium spp. and other marine organisms. Overall, our results contribute to a deeper understanding of the P cycle in the Red Sea and have implications for developing novel strategies for P management in marine ecosystems.

A Universal Solid-Phase Synthetic Strategy for Ultrafine Intermetallic Libraries Confined in Ordered Mesoporous Carbon.

Ordered intermetallic nanocatalysts supported on high-surface-area skeletons are of great importance in catalysis and have disclosed notable catalytic activity and stability that are remarkably better than their random alloy counterparts. Ultrafine intermetallic nanocatalysts are synthetically challenging, especially for universal and scaled-up synthesis, because of inevitable sintering and phase separation under high temperatures that promote atomic alloying and ordering. Herein, a universal solid-phase and scaled-up method is reported for synthesizing ultrafine intermetallic nanocatalysts with uniform size distributions and wide compositional spaces confined in ordered mesoporous carbon (OMC) supports, where the strong physical confinement and chemical interaction between metals and sulfur/mesoporous templates remarkably suppress the high-temperature sintering and phase separation even up to 1000°C. Libraries of intermetallic nanocatalysts are successfully synthesized including 52 combinations of host platinum/palladium/rhodium with 15 guest elements confined in 4 OMC supports. Taking oxygen reduction and hydrogen evolution reactions as examples, the intermetallic PtFe nanocatalysts hold remarkable performance, whose activities reach up to ten times higher than commercial Pt/C and also are comparable to the best electrocatalysts reported recently. This feasible synthetic strategy offers an intermetallic library spanning from binary to senary materials for industrial synthesis and applications.

Exploring the adsorption characteristics of quinoline derivatives on iron via ab initio DFT simulations and COSMO-RS profiles

Quinoline derivatives have been the subject of extensive research due to their excellent electronic properties and wide range of applications. This study conducts a comprehensive computational examination of the adsorption properties of substituted quinoline derivatives on Fe(110) surfaces. Four specific compounds, namely 2-amino-7-hydroxy-4-phenyl-1,4-dihydroquinoline-3-carbonitrile (QN1), 2-amino-7-hydroxy-4-(p-tolyl)-1,4-dihydroquinoline-3-carbonitrile (QN2), 2-amino-7-hydroxy-4-(4-methoxyphenyl)-1,4-dihydroquinoline-3-carbonitrile (QN3), and 2-amino-4-(4-(dimethylamino)phenyl)-7-hydroxy-1,4-dihydroquinoline-3-carbonitrile (QN4) were investigated using first-principles density functional theory (DFT) calculations along with COSMO-RS analysis for solvation properties. Our results revealed that the presence of functional groups significantly influence the adsorption strength on Fe(110) surfaces. Quinoline molecules have adsorbed on the iron surface through complex mechanisms involving physical interactions and charge transfer. Specifically, QN1 and QN4 showed strong physical interactions with iron atoms while QN2 and QN3 exhibited high affinity to coordinate with Fe atoms. The stability of coordinated quinolines was enhanced by a notable charge redistribution and bond formation as observed via projected density of states (PDOS). On the other hand, electron density difference (EDD) and electron localization function (ELF) iso-surfaces highlighted the critical role of van der Waals interactions, predominantly influenced by nitrogen atoms, in stabilizing the adsorbed molecules. The COSMO-RS analysis elucidated the solvation characteristics, emphasizing the importance of hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA) in the interaction of quinolines with water molecules. Overall, this study provides crucial insights into the molecular mechanisms underlying the corrosion inhibition properties of quinoline derivatives, emphasizing the influence of functional groups and solvation effects on adsorption behavior and stability.

Plant Extracellular Nanovesicle-Loaded Hydrogel for Topical Antibacterial Wound Healing In Vivo.

Bacterial infections impede wound healing and pose significant challenges in clinical care. There is an immediate need for safe and targeted antivirulence agents to fight bacterial infections effectively. In this regard, bioderived nanovesicles have shown significant promise. This work demonstrated significant antibacterial properties of extracellular nanovesicles derived from plant (mint) leaf juice (MENV). A hydrogel (HG) was developed using oxidized alginate and chitosan and loaded with antibacterial MENVs (MENV-HG). This formulation was investigated for topical HG dressings to treat Gram-positive Micrococcus luteus and Gram-negative Escherichia coli-invasive wounds. The developed HG was injectable, biocompatible (>95% cell was viable), nonhemolytic (<5% hemolytic capacity), self-healing and exhibited strong physical and mechanical interactions with the bacteria cells (MENV-HG-treated bacteria were significantly more elastic compared to the control in both M. luteus (1.01 ± 0.3 MPa, p < 0.005 vs 5.03 ± 2.6) and E. coli (5.81 ± 2.1 MPa vs 10.81 ± 3.8, p < 0.005). MENV-HG was topically applied on wounds with a slow MENV release profile, ensuring effective healing. These in vivo results demonstrated decreased inflammation and expedited healing within 10 days of treatment (wound area closure was 99% with MENV-HG treatment and 87% for control). Taken together, MENV-HGs have the potential for a scalable and sustainable wound dressing strategy that works satisfactorily for bacteria-infected wound healing and to be validated in clinical trials.

Omics-based Analysis of Bhadradarvadi Kashayam in Managing Rheumatoid Arthritis via CXCL8-CXCR1/2 axis, MAPK and NF-κB Signaling Pathways - A Network Pharmacology Approach

With the advances in the field of medicine there is an increase in the geriatric population and rheumatoid arthritis is one of the common diseases that affect this cohort. The modern medicines that are used for the treatment of rheumatoid arthritis provide a symptom-based treatment and there are studies showing severe side effects for some of the medicines being used. But there are shreds of evidence in traditional medical texts for the treatment of rheumatoid arthritis which gives an increased therapeutic coverage with less to no side effects. Bhadradarvadi kashayam (concoction) is one of the most commonly preferred and prescribed Ayurvedic medicine for managing the disease. In this study, we are investigating the mode of action of this kashayam by employing a network pharmacology-based framework which included the analysis of the cross-talks between the active ingredients of the kashayam and major molecules involved in the disease, the transcription factors and various pathways in which they are involved. Based on the systems pharmacology approach, 57 active compounds and a total of 377 potential targets with their interacting partners, and the targets associated with comorbidities were identified. The PPI network was analyzed to understand the topological index for screening the hub proteins such as MAPK1, MAPK14, FYN and CXCL8, which were found to be enriched in various signaling pathways. Furthermore, molecular docking analysis validated the strong physical interaction between the hub proteins and the corresponding active compounds from BDK. Overall, the study sheds light on the pharmacological mechanism of Bhadradarvadi kashayam against Rheumatoid Arthritis and also highlights that there are traditional herbal remedies imparted by the Ayurveda system of medicine which has the least side effects compared to modern medicines.

One-step soaking strategy toward mechanobiological double-network hydrogel with improving chondrogenesis capacity

Cartilage tissue engineering (CTE) is a promising strategy for addressing the persistent challenges in healing articular cartilage defects in the clinic, aiming to manufacture scaffolds with ideal mechanical characteristics that can provide a conducive microenvironment for the reconstruction or replacement of damaged cartilage defects. Easy operation, excellent mechanical strength, remarkable biocompatibility, and inherent capacity to promote cartilage formation are essential in CTE. This study designed a mechanobiological double-network (DN) hydrogel (KCS-PAA-Mn2+) through a one-step soaking strategy of immersing the composite hydrogel (KCS-PAA) of kartogenin (KGN)-conjugated short-chain chitosan (CS) covalent with polyacrylic acid (PAA) in manganese chloride (MnCl2) solution. Due to the strong physical interactions of CS chain-entanglement network and carboxylate-Mn2+ complex inducing polymer aggregation state transitions, the KCS-PAA-Mn2+ DN hydrogel exhibited exceptional mechanical characteristics, such as high tensile property (strength: 0.24 MPa at a strain of 552 %; toughness: 0.66 MPa), compressibility (strength: 51.98 MPa at a strain of 95 %; compressive modulus: 0.09 MPa), controllable swelling behavior (~327 %), and sustained drug release (>2 weeks). Moreover, in vitro biological studies demonstrated that the KCS-PAA-Mn2+ DN hydrogel not only promoted cell growth and proliferation but also enhanced the expression of genes specific to cartilage and the release of cartilage extracellular matrix (ECM) by bone mesenchymal stem cells (BMSCs), thus enabling a continuous concentration for a long period and persistently enhancing its chondrogenic efficiency. Overall, this soaking methodology reported here is universal to construct mechanically bioactive scaffolds that could expand their bio-applicability with simultaneous advantages of mechanical supports, tailorable swelling, sustainable drug release and long-lasting biological function, thus facilitating the advancement of cartilage-engineered hydrogel biomaterials to a higher level.

Antibacterial and anti-inflammatory polyethyleneimine/polyacrylic acid hydrogel loaded with CeO2 quantum dots for wet tissue wound dressings

Searching for an antibacterial and anti-inflammatory dressing that can stably adhere to wet tissues remains a momentous clinical challenge, especially in the context of treatment failure due to multi-drug-resistant bacteria. Using a hard template method in combination with an in situ chelating strategy, three-dimensional nitrogen-doped graded porous carbon anchored 1.5–2.5 nm CeO2 quantum dots (CeO2-QDs) were tailor-designed in this study. Using the size effect, CeO2-QDs have a higher percentage of Ce3+ and oxygen vacancies that could amplify their antibacterial effects. Polyethyleneimine/polyacrylic acid (PEA) powder could self-gel and be adhesive due to its strong physical interactions, which make it an ideal carrier for CeO2-QDs. PEA@50 (mg/mL) CeO2-QDs hydrogel and PEA@75 (mg/mL) CeO2-QDs hydrogel with moderate doses of CeO2-QDs show a superior antibacterial effect against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) strains. Furthermore, PEA@50CeO2-QDs hydrogels possess excellent anti-inflammatory capacity through their antioxidant activity, which could promote macrophage M2 phenotype polarization. More importantly, cytotoxicity assays on L929 fibroblasts show that PEA@CeO2-QDs hydrogels have no significant toxicity, and a significant proliferative effect could be observed. Overall, PEA@50CeO2-QDs hydrogels have the potential to become a multifunctional wet tissue dressing with anti-inflammatory and antiseptic properties to promote the healing of infected wounds.

Greenly building strong interactions between epoxy and carbon fiber fabric via vapor assisted ozone

AbstractTo enhance the performance of carbon fiber reinforced polymer (CFRP), it is crucial to establish robust interactions between epoxy and carbon fiber fabric (CFF). Herein, CFF was treated by an optimized H2O2/H2O/O3 oxidation method. The chemical and physical properties of the treated CFFs were meticulously characterized. For comparison, CFF, O3 treated CFF, and H2O/O3 treated CFFs were also examined. It was found that H2O2/H2O/O3 oxidized CFF more effectively than either O3 or H2O/O3. Reactive O groups were extensively grafted onto the surface of the H2O2/H2O/O3 oxidized CFF, leading to an increase in surface energy. Additionally, numerous defects were introduced on the surface of the H2O2/H2O/O3 oxidized CFF, significantly enhancing its surface roughness. Consequently, the interlaminar shear strength of H2O2/H2O/O3 oxidized CFF reinforced epoxy composite reached 63.31 ± 2.50 MPa, which is 43.3% higher than that of CFF reinforced epoxy composite. The fracture surface morphology and differential scanning calorimetry studies confirmed the presence of strong interfacial chemical interactions, while the increased surface roughness ensured robust interfacial physical interactions. Based on these findings, the mechanisms of the H2O2/H2O/O3 oxidized CFF reinforcing epoxy were proposed. The present work aims to give out some ideas for the fabrication of green and advanced CFRP.Highlights CFF was effectively oxidized by an optimized H2O2/H2O/O3 method eco‐friendly. Improved the interlaminar shear strength of the epoxy composite by 43.3%. Both the strong interfacial chemical and physical interactions were confirmed. The reinforcing mechanism is attributed to the robust interactions.

A modular framework for implicit 3D–0D coupling in cardiac mechanics

In numerical simulations of cardiac mechanics, coupling the heart to a model of the circulatory system is essential for capturing physiological cardiac behavior. A popular and efficient technique is to use an electrical circuit analogy, known as a lumped parameter network or zero-dimensional (0D) fluid model, to represent blood flow throughout the cardiovascular system. Due to the strong physical interaction between the heart and the blood circulation, developing accurate and efficient numerical coupling methods remains an active area of research. In this work, we present a modular framework for implicitly coupling three-dimensional (3D) finite element simulations of cardiac mechanics to 0D models of blood circulation. The framework is modular in that the circulation model can be modified independently of the 3D finite element solver, and vice versa. The numerical scheme builds upon a previous work that combines 3D blood flow models with 0D circulation models (3D fluid–0D fluid). Here, we extend it to couple 3D cardiac tissue mechanics models with 0D circulation models (3D structure–0D fluid), showing that both mathematical problems can be solved within a unified coupling scheme. The effectiveness, temporal convergence, and computational cost of the algorithm are assessed through multiple examples relevant to the cardiovascular modeling community. Importantly, in an idealized left ventricle example, we show that the coupled model yields physiological pressure–volume loops and naturally recapitulates the isovolumic contraction and relaxation phases of the cardiac cycle without any additional numerical techniques. Furthermore, we provide a new derivation of the scheme inspired by the Approximate Newton Method of Chan (1985), explaining how the proposed numerical scheme combines the stability of monolithic approaches with the modularity and flexibility of partitioned approaches.

A Janus hydrogel sealant with instant wet adhesion and anti-swelling behavior for gastric perforation repair

Achieving instant adhesion on wet tissues and preventing the concurrently occurred postoperative tissue adhesion remain tough challenges but urgently demanded. And the deteriorated cohesion and adhesion caused by undesired swelling of hydrogel could not be ignored. Herein, we developed a Janus hydrogel with instant wet adhesion and anti-swelling behavior, based on poly (acrylic acid) (PAA), gelatin (GT) and hyperbranched polymers modified with catechol (HBPC). The asymmetric structure is achieved through complexed one-side of the hydrogel with cationic polymers. The strong physical interaction between PAA and GT formed during immersing in water enhanced the mechanical strength of the gels. And the hydrogel exhibits good anti-swelling behavior, which circumvents the limitations of conventional hydrogel caused by swelling. Water drainage induced by hydrophobic component and the following removal of water residuals achieved by hydrophilic PAA synergistically enhanced the instant wet adhesion of the hydrogel. Besides, pH-responsive protonation of carboxyl groups in PAA equipped the adhesive with extreme acid-tolerance. The in vivo evaluation results demonstrated that the asymmetric adhesive hydrogel could promote the repair of gastric perforation while reducing the risk of postoperative tissue adhesion. The hydrogel with asymmetric wet adhesion might provide valuable insights into the establishment of bioadhesives for gastric sealing and repair.

Two-dimensional GeSe monolayer doped with single main-group element atom for hazardous gas detection: A first-principles study

Currently, the identification of sensing materials that can selectively and rapidly respond to hazardous gases is urgent for safeguarding the environment and human life. The adsorption of hazardous gas molecules (NO, NO2, SO2, CO, and H2S) on the GeSe monolayer doped with single main-group element atom is investigated and compared based on first-principles density functional theory (DFT). NO2 has the highest adsorption energy and charge transfer adsorbed on both pristine GeSe and doped GeSe monolayer. At ambient temperature, for any doped GeSe monolayers adsorbing gas molecules (including H2O, O2, and N2), the occupation function value of NO2 is the highest. The analysis of density of states (DOS) and band structure indicates that NO2 interacts with different modified GeSe monolayers in terms of atomic orbitals. Moreover, Al-GeSe has the largest change of work function before and after the adsorption of NO2, meaning that Al-GeSe has the greatest response to NO2. current-voltage (I-V) characteristics demonstrate that Al-GeSe exhibits a remarkable current change after the adsorption of NO2. These results illustrate that Al-GeSe has a strong physical and chemical interaction with NO2, yielding a high response and selectivity, which is anticipated to be the optimal gas sensing material for NO2.

Hydrogen-Bonding-Driven Nontraditional Photoluminescence of a β-Enamino Ester.

Nontraditional luminogens (NTLs) do not contain any conventional chromophores (large π-conjugated structures), but they do show intrinsic photoluminescence. To achieve photoluminescence from NTLs, it is necessary to increase the extent of through-space conjugation (TSC) and suppress nonradiative decay. Incorporating strong physical interactions such as hydrogen bonding is an effective strategy to achieve this. In this work, we carried out comparative studies on the photoluminescence behaviors of two β-enamino esters with similar chemical structures, namely methyl 3-aminocrotonate (MAC) and methyl (E)-3-(1-pyrrolidinyl)-2-butenoate (MPB). MAC crystal emits blue fluorescence under UV irradiation. The critical cluster concentration of MAC in ethanol solutions was determined by studying the relationship between the photoluminescence intensity (UV-visible absorbance) and concentration. Furthermore, MAC exhibits solvatochromism, and its emission wavelength redshifts as the solvent polarity increases. On the contrary, MPB is non-emissive in both solid state and solutions. Crystal structures and theoretical calculation prove that strong inter- and intramolecular hydrogen bonds lead to the formation of large amounts of TSC of MAC molecules in aggregated states. No hydrogen bonds and thus no effective TSC can be formed between or within MPB molecules, and this is the reason for its non-emissive nature. This work provides a deeper understanding of how hydrogen bonding contributes to the luminescence of NTLs.

Physicochemical Characterization of Chitosan/Poly-γ-Glutamic Acid Glass-like Materials.

This paper sets up a new route for producing non-covalently crosslinked bio-composites by blending poly-γ-glutamic acid (γ-PGA) of microbial origin and chitosan (CH) through poly-electrolyte complexation under specific experimental conditions. CH and two different molecular weight γ-PGA fractions have been blended at different mass ratios (1/9, 2/8 and 3/7) under acidic pH. The developed materials seemed to behave like moldable hydrogels with a soft rubbery consistency. However, after dehydration, they became exceedingly hard, glass-like materials completely insoluble in water and organic solvents. The native biopolymers and their blends underwent comprehensive structural, physicochemical, and thermal analyses. The study confirmed strong physical interactions between polysaccharide and polyamide chains, facilitated by electrostatic attraction and hydrogen bonding. The materials exhibited both crystalline and amorphous structures and demonstrated good thermal stability and degradability. Described as thermoplastic and saloplastic, these bio-composites offer vast opportunities in the realm of polyelectrolyte complexes (PECs). This unique combination of properties allowed the bio-composites to function as glass-like materials, making them highly versatile for potential applications in various fields. They hold potential for use in regenerative medicine, biomedical devices, food packaging, and 3D printing. Their environmentally friendly properties make them attractive candidates for sustainable material development in various industries.

Structural synthesis of the reconfigurable legged mobile lander for strong geometry-physical interaction with extraterrestrial environment

To design the engineering prototype of reconfigurable legged mobile lander (ReLML) for strong geometry-physical interaction with extraterrestrial environment, this paper proposes a tailored structural synthesis methodology unifying kinematic geometry and statics. Compared with our preceding works, three inbuilt operation modes are first integrated: adjusting mode is a totally new mode defined as three rotations (3R) with a strong geometrical adaptation to hostile terrain; landing mode is redefined as two rotations one translation (2R1T), inherits Chang'E lander to survive from strong impact interaction; roving mode turns into the other 2R1T motion for good motion/force interactivity. The interaction characteristics (motion, force, energy) between ReLML and environment are extracted to derive output finite motions and instantaneous wrenches of leg end-effector, following the principles of optimal force system equilibrium and work efficiency. The motion and force synergistic syntheses of metamorphic limb and joint are implemented to design and assemble mechanical generators. The ReLML can serve the alien base construction and adjustable launch bracket. The unified structural synthesis methodology of kinematic geometry and statics is universal and effective for designing parallel mechanisms and reconfigurable mechanisms, especially for strong physical interaction scenarios.

A Conformable and Tough Janus Adhesive Patch with Limited 1D Swelling Behavior for Internal Bioadhesion

AbstractAdvanced bioadhesion techniques have offered unprecedented opportunities for life‐saving internal surgical procedures. However, most existing bioadhesives failed to rapidly establish long‐lasting reliable biointerface and effectively reconstruct normal physiological function in the body fluid‐rich and inevitable dynamic internal environment. Herein, a PEGylated poly(glycerol sebacate)‐based Janus adhesive patch (PEGS‐based JAP) is developed by integrating physically crosslinked guanidinylated PEGS (PEGSG) and acryloylated PEGS‐chemically crosslinked poly(acrylic acid)‐N‐hydrosuccinimide ester (PEGSA‐crosslinked PAAc‐NHS) with a single‐sided zwitterionic polymer‐interpenetrated layer. The dry JAP can rapidly absorb the unpleasant interfacial water and effectively form strong physical interactions with wet tissues. Benefiting from the amphiphilic nature of PEGSG and a simple spatial‐confined drying process, the JAP is allowed to resist excessive swelling and limitedly swell along one direction to avoid deterioration of the as‐established conformable patch‐tissue interface. Moreover, covalent interactions formed subsequently can further improve the adhesive strength and ensure a long‐lasting reliable adhesion. Meanwhile, the notch‐insensitive and puncture‐resistant JAP can achieve tough adhesion to adapt to the dynamic conditions owing to the highly efficient energy‐dissipation mechanism of the physically cross‐linked network. Combining the above ideal features with the desirable postoperative anti‐adhesion ability, the PEGS‐based JAP is demonstrated to be a promising candidate for internal tissue adhesion and function reconstruction.

Polydopamine and polyethyleneimine comodified carbon fibers/epoxy composites with gradual and alternate rigid‐flexible structures: Design, characterizations, interfacial, and mechanical properties

AbstractPolymer composites with tailored structure and enhanced properties and functions have attracted great attentions due to their wide applications in materials science, nanotechnology, and engineering science. In this work, we demonstrate the innovative concepts of fabricating both gradual “rigid‐flexible” and alternate “rigid‐flexible” structures, which are achieved by altering the grafting sequence of flexible polyethyleneimine with high flexibility and polydopamine with suitable rigidity. Then, the effect of different rigid‐flexible structures on the structure and properties of the carbon fiber‐epoxy (CF/EP) composites are studied. It is found that the composites reinforced by the alternate rigid‐flexible polymer layer possess superior interfacial effects and mechanical properties. Compared with the CF/EP without polymer layer modification, the rigid‐flexible layer contributes to about 80.3% and 167.3% on the interfacial shear strength and the impact strength of final composites. These great improvements are attributed to the complex crack propagation path, more energy consumption, wider interface region, higher wettability, as well as strong physical and chemical interactions. This work provides practical and scalable potentials for regulating the structure and functions of the CF‐reinforced polymer composites by optimal interfacial design.

Pea eggplant (Solanum torvum Swartz) is a source of plant food polyphenols with SARS-CoV inhibiting potential.

Pea eggplant (Solanum torvum Swartz) commonly known as turkey berry or 'terung pipit' in Malay is a vegetable plant widely consumed by the local community in Malaysia. The shrub bears pea-like turkey berry fruits (TBFs), rich in phytochemicals of medicinal interest. The TBF phytochemicals hold a wide spectrum of pharmacological properties. In this study, the TBF phytochemicals' potential inhibitory properties were evaluated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of the Coronavirus disease 2019 (COVID-19). The TBF polyphenols were screened against SARS-CoV receptors via molecular docking and the best receptor-ligand complex was validated further by molecular dynamics (MD) simulation. The SARS-CoV receptor structure files (viral structural components) were retrieved from the Protein Data Bank (PDB) database: membrane protein (PDB ID: 3I6G), main protease (PDB ID: 5RE4), and spike glycoproteins (PDB ID: 6VXX and 6VYB). The receptor binding pocket regions were identified by Discovery Studio (BIOVIA) for targeted docking with TBF polyphenols (genistin, kaempferol, mellein, rhoifolin and scutellarein). The ligand and SARS-CoV family receptor structure files were pre-processed using the AutoDock tools. Molecular docking was performed with the Lamarckian genetic algorithm using AutoDock Vina 4.2 software. The best pose (ligand-receptor complex) from the molecular docking analysis was selected based on the minimum binding energy (MBE) and extent of structural interactions, as indicated by BIOVIA visualization tool. The selected complex was validated by a 100 ns MD simulation run using the GROMACS software. The dynamic behaviour and stability of the receptor-ligand complex were evaluated by the root mean square displacement (RMSD), root mean square fluctuation (RMSF), radius of gyration (Rg), solvent accessible surface area (SASA), solvent accessible surface volume (SASV) and number of hydrogen bonds. At RMSD = 0, the TBF polyphenols showed fairly strong physical interactions with SARS-CoV receptors under all possible combinations. The MBE of TBF polyphenol-bound SARS CoV complexes ranged from -4.6 to -8.3 kcal/mol. Analysis of the structural interactions showed the presence of hydrogen bonds, electrostatic and hydrophobic interactions between the receptor residues (RR) and ligands atoms. Based on the MBE values, the 3I6G-rhoifolin (MBE = -8.3 kcal/mol) and 5RE4-genistin (MBE = -7.6 kcal/mol) complexes were ranked with the least value. However, the latter showed a greater extent of interactions between the RRs and the ligand atoms and thus was further validated by MD simulation. The MD simulation parameters of the 5RE4-genistin complex over a 100 ns run indicated good structural stability with minimal flexibility within genistin binding pocket region. The findings suggest that S. torvum polyphenols hold good therapeutics potential in COVID-19 management.

Low-cost preferential different amine grafted silica spheres adsorbents for DAC CO2 removal

DAC CO2 capture is gaining wide attention as one of the most difficult carbon approaches to tackle climate change. In this work, different pore-size silica spheres were grafted using different amine groups such as APTES, APTMS, and Diamine. Herein, all samples based on the wet and dry grafting method were used for CO2 adsorption isotherm at room temperature and pressure (298 K and 1 bar). The sample based on the wet grafting (Silica-APTES-W) sample shows the highest CO2 uptake 1.67 mmol/g. Also, the adsorption isotherm of the Silica-APTES-W sample was showed a high capacity of CO2 1.2 mmol/g at 25 °C, which describes the strong physical interaction between CO2 and amine. The isosteric adsorption of Silica-APTES-W also confirmed that the physical adsorption was dominant because of low adsorption heat ranging from 23 to 37 kJ/mol. Also, the fixed bed experiment was conducted with 2000 ppm CO2 that obtains the optimal working capacity 4.5 mL/g with the lowest regeneration temperature 90 °C. It was shown that Silica-APTES-W sample was superior performance for DAC CO2 capture in practical applications.

High CX3CR1 expression predicts poor prognosis in paediatric acute myeloid leukaemia undergoing hyperleukocytosis.

Paediatric AML patients with hyperleukocytosis have a poor prognosis and higher early mortality. Therefore, more studies are needed to explore relevant prognostic indicators and develop effective prevention strategies for this type of childhood AML. All original data were obtained from the TARGET database. First, we explored meaningful differentially expressed genes (DEGs) between the hyperleukocytosis group and the non-hyperleukocytosis group. Next, we screened and identified valuable target genes using univariate Cox regression, Cytoscape software, and Kaplan-Meier survival curves. Finally, the coexpressed genes, functional networks, and immune-related activities associated with the target gene were deeply analysed by the GeneMANIA, LinkedOmics, GEPIA2021, TISIDB, and GSCA databases. We selected 1229 DEGs between the hyperleukocytosis group and the non-hyperleukocytosis group in paediatric AML patients. Among them, 495 DEGs were significantly linked with the overall survival of paediatric AML patients. Further, we discovered that CX3CR1 was a promising target gene. Meanwhile, we identified CX3CR1 as an independent prognostic predictor. Besides, we showed that CX3CR1 had strong physical interactions with CX3CL1. Additionally, functional network analysis suggested that CX3CR1 and its coexpressed genes modulated immune response pathways. Subsequent analysis found that immune cells with a high median value of CX3CR1 were monocytes, resting NK cells and CD8 T cells. Finally, we observed that CX3CR1 expression correlated with infiltrating levels of immune cells and immune signatures. Elevated CX3CR1 expression may be an adverse prognostic indicator in paediatric AML patients undergoing hyperleukocytosis. Moreover, CX3CR1 may serve as an immunotherapeutic target for AML with hyperleukocytosis in children.

Environmental-Friendly Adsorbent Composite Based on Hydroxyapatite/Hydroxypropyl Methyl-Cellulose for Removal of Cationic Dyes from an Aqueous Solution.

The aim of this study is to develop a new, efficient, and inexpensive natural-based adsorbent with high efficacy for the cationic dye methylene blue (MB). A natural-based nanocomposite based on hydroxyapatite (HAp) and hydroxypropyl methylcellulose (HPMC) was selected for this purpose. It was synthesized by the dissolution/reprecipitation method. A film with a homogeneous and smooth surface composed of nanoparticles was prepared from the nanocomposite. HPMC and HAp biopolymers were selected due to their compatibility, biodegradability, and non-toxicity. Total reflectance infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and calorimetric/thermal gravimetric (DSC/TGA) analysis results revealed the existence of strong physical interaction between the composite components. Scanning electron microscopy (SEM) observations show a composite sheet with a homogenous and smooth surface, indicating excellent compatibility between HPMC and HAp in the composite. The nanocomposite was evaluated as an adsorbent for organic dyes in an aqueous solution. The effects of solution pH, initial MB concentration, composite concentration, and adsorption time on the adsorption efficiency were evaluated. The highest adsorption rate was seen as 52.0 mg of MB/g composite. The adsorption rate reached equilibrium in about 20 min. Fitting of the adsorption data to the Langmuir and Freundlich adsorption models was investigated. Results showed that the adsorption process follows the Langmuir isotherm model. The kinetic study results revealed that the adsorption process was pseudo-second-order. The herein composite is an excellent alternative for use as contemporary industrial-scale adsorbents.