Pattern Information Research Articles

Sedimentary provenance and paleogeographic environment of a Mississippian coal-bearing unit in South China: Constraints from detrital zircon U-Pb ages and sedimentologic and geochemical evidence

The Mississippian Xiangbai Formation in South China is one of the oldest coal-bearing sedimentary units in China. However, the sedimentary provenance, paleogeography, and coal formation patterns of the coal-bearing strata are not well constrained. We address this key issue by using a combination of detrital zircon U-Pb data, geochemical analyses of mudstone and shale, drilling data, and geologic field observations. With the exception of the early Paleozoic orogenic events (ca. 440–420 Ma) in the eastern part of the study area, the samples from the Xiangbai Formation exhibit similar detrital zircon U-Pb age distribution with major age peaks at ca. 980–960 Ma and several subordinate age peaks at ca. 800–780 and 600–500 Ma. These detrital zircon grains mainly originated from recycled sedimentary units. Field and drilling data reveal that the Xiangbai Formation was formed in a tidal flat environment with water depth gradually increasing from the bottom to the top, indicating an overall trend of transgression. The Mississippian Xiangbai Formation was deposited in an interglacial period. The Lower Xiangbai Formation was deposited in a relatively cold paleoclimate, gradually transitioning upwards to a warm and humid climate, creating favorable conditions for coal formation. The alternation of warming and cooling climates triggered high-frequency eustatic fluctuations, which led to multiple sedimentary cycles and resulted in thin, unstable coal seams within the Xiangbai Formation. Mississippian sedimentary paleogeography, palaeoclimate, and sedimentary provenance together dominate the coal-bearing clastic sediments in southwestern South China.

Aspectual Pair Formation in Russian Verbs: A Cognitive Approach

Aspectual pair formation in Russian verbs represents a core grammatical feature that governs the temporal and contextual framing of actions. Traditional approaches to aspect focus on morphological mechanisms such as prefixation, suffixation, and suppletion, yet they often fail to address irregularities and semantic nuances. This study adopts a cognitive linguistic perspective, exploring how conceptual metaphors, image schemas, and mental mappings underpin aspectual distinctions. By analyzing patterns of pair formation, including both regular and irregular verbs, the research highlights the cognitive processes that align with bounded and unbounded conceptualizations of actions. The findings contribute to linguistic theory by integrating semantic and cognitive frameworks, while practical applications offer innovative strategies for teaching aspect to learners through mental imagery and contextualized learning. Challenges and unanswered questions, such as the treatment of suppletive forms and cross-linguistic comparisons, underscore the need for further interdisciplinary research to refine this approach.

Effects of Polydeoxyribonucleotide (PDRN) on Endosinus Bone Regeneration Following Sinus Floor Elevation: An Experimental InVivo Pilot Study.

To determine the effect of polydeoxyribonucleotide (PDRN) on endosinus bone regeneration in a rabbit sinus model at sequential healing time points. Eighteen New Zealand white rabbits were used. Bilateral sinus floor elevation (SFE) was performed. Two groups were randomly assigned to each sinus: (1) test group, in which SFE was performed using collagenated bone substitute material soaked with PDRN (concentration 2.0 mg/mL, dose 0.5 mL), and (2) control group, in which SFE was performed using collagenated bone substitute material only. The experimental animals were sacrificed at 2, 4, and 8 weeks (n = 6 at each healing time point). Microcomputed tomography (micro-CT), histologic, and histomorphometric analyses were performed. The micro-CT analysis revealed statistically significant increases in the mineralized tissue volume between 4 and 8 weeks (p < 0.05). Histologically, no specific intergroup difference was found in the pattern of new bone formation. Histomorphometrically, the area of newly formed bone (NB) was larger in the test group than in the control group at all healing time points (1.4 vs. 1.2 mm2 at 2 weeks, 3.4 vs. 1.9 mm2 at 4 weeks, and 5.7 vs. 4.5 mm2 at 8 weeks; median value), but the difference was statistically significant only at 4 weeks (p < 0.05). NB in set regions of interest (ROI_C, ROI_W, and ROI_M) tended to be greater in the test group than in the control group without statistical significance (p > 0.05). PDRN appeared to enhance new bone formation at all healing time points, but the improvement was statistically significant only at 4 weeks.

Carbon fiber reinforced polymer (CFRP) laminates: flexural strengthening method for prestressed concrete beams with anchorage loss

Abstract Post-tensioning (PT), a method of pre-stressing, involves the use of high-strength steel strands/ tendons to reinforce concrete or other materials. On the contrary, Carbon Fiber-Reinforced Polymers (CFRP) are lightweight, high-strength materials with used to strengthen concrete structures by adhering the polymer to the concrete element. Challenges with post-tensioned elements include reverse curvature of the post-tensioning strands, tendon misplacement, and frequent damage in the anchorage and dead-end zones. These difficulties frequently cause bulging of the surrounding concrete, even at lower stress levels, and can lead to concrete bursting when tension exceeds certain threshold. This study investigates into the potential of CFRP strengthening technique to improve the flexural capacity of post-tensioned concrete beams with anchorage loss. Through an experimental program, the study compares the performance of control beams to those reinforced with different layers of CFRP. The results of this study demonstrated that there was a significant increase in flexural capacity, ranging from 45.31% to 78.62% for single layers and 87.17% to 153% for double layers of CFRP sheet. Additionally, the research examines how different levels of prestressing and CFRP wraps influence crack formation and delamination patterns of carbon fiber, with promising results. It was also noted that optimal usage of CFRP fibers and tendons is found to be critical. The study suggests exploring alternative fiber types and orientations for future study.

Open-End Control of Neurite Outgrowth Lengths with Steep Bending Confinement Microchannel Patterns for Miswiring-Free Neuronal Network Formation.

Wiring technology to control the length and direction of neurite outgrowth and to connect them is one of the most crucial development issues for forming single-cell-based neuronal networks. However, with current neurite wiring technology, it has been difficult to stop neurite extension at a specific length and connect it to other neurites without causing miswiring due to over-extension. Here, we examined a novel method of wiring neurites without miswiring by controlling the length of neurites in open-ended bending microchannel arrays connected beyond the maximum bending angle of neurite outgrowth. First, we determined the maximum bending angle of neurite elongation to pass through the bending point of a bending microfluidic channel; the maximum angle (the critical angle) was 90°. Next, we confirmed the control of neurite outgrowth length in open-ended microchannels connected at 120°, an angle beyond the maximum bending angle. The neurites stopped when elongated to the bend point, and no further elongation was observed. Finally, we observed that in bending microchannel arrays connected at an angle of 120°, two neurite outgrowths stopped and contacted each other without crossing over the bend point. The results show that the steep bending connection pattern is a robust open-end neurite wiring technique that prevents over-extension and miswiring.

Analysis of bearing capacity of consolidated clay under the track load of deep-sea mining vehicle

Analysis of bearing capacity of seabed consolidation foundation is conducted. Two types of bearing capacity along the vertical and horizontal directions are derived. The stress distribution between tooth plates is analyzed using the slip line field theory, and the soil between the tooth plates is divided into wedge-shaped rigid zones, passive slip zones, and transition zones. The analysis results show that the ratio of tooth depth to tooth spacing significantly affects the formation pattern of the failure zone between the tooth plates. When the depth-to-spacing ratio is small, all three zones are present, while as the ratio gradually increases, the rigid wedge-shaped zone also increases, the transition zone becomes smaller, and the passive zone disappears. Therefore, it is advisable to arrange a smaller depth-to-spacing ratio to fully exploit the strength potential of the soil between the tooth plates. The results of the finite element method (FEM) analysis also show the existence of active and passive zones beneath the crawler tracks, and due to the combination of orthogonal loadings in the vertical and horizontal directions, there is a phenomenon of skewed stress bubbles in the foundation soil beneath and correctness of the derived bearing capacity of the foundation in this study.

Coassembly of Cell-Penetrating Peptide Octaarginine with Acetazolamide: Emergent Interactions with E. coli.

The investigation of established pharmaceutical agents for recalibrating usage strongly supplements new drug development. In this work, we have prepared coassembled complexes of acetazolamide (AZM) with the cationic peptide octaarginine (R8) in an attempt to enhance its potency and scope of use. R8 and AZM in different weight ratios coassemble into remarkable nano- and microstructures such as ribbons, sheets, and stick-like structures. A combination of FTIR, XRD, SEM, and DSC has been used to characterize the R8:AZM coassemblies. The sulfonamide SO2 and NH2 groups of AZM are associated with the guanidinium amine, free amine, and terminal carbonyl groups of R8 resulting in distinctive topologies. Treatment of Escherichia coli with the complexes results in a distinctive pattern of membrane disruption and pore formation. The R8:AZM coassemblies inhibit carbonic anhydrase and E. coli growth with greater efficiency compared to bare AZM. The 1:5 w/w complex leads to pronounced outer and inner membrane rupture and significantly restricts glucose uptake by E. coli. The ability of R8 and AZM to coassemble into a distinctive set of structures based solely on differences in their relative proportions and their engagement with E. coli as more than the sum of their parts are novel facets of R8 and AZM behavior and underscore a straightforward and elegant approach for enhancing the scope of use of small molecule drugs.

ПАМЯТИ ЛИДИИ ВАСИЛЬЕВНЫ МОСКАЛЕНКО (03.02.1937–08.06.2024)

On June 8, 2024, the life of Lydia Vasilievna Moskalenko, candidate of geographical sciences, senior researcher of the Laboratory of Hydrophysics and Modeling of the Southern Branch of the Institute of Oceanology of the Russian Academy of Sciences (SB IO RAS), ended. Lydia Vasilievna was a major scientist and a remarkable person who devoted her entire life to oceanology. Her work yielded important scientific results that made it possible to clarify the patterns of formation of the hydrological structure and dynamics of the waters of the Mediterranean and Black Seas. The article briefly reflects the life path of L. V. Moskalenko and notes her main achievements in Russian oceanology.

Molecular insights from structural dynamics of HER2-inhibitor complexes pave the way for new breast cancer drugs

The human epidermal growth factor receptor 2 (HER2) is closely associated with the development and progression of breast cancer, making it a critical target for therapeutic interventions. In this study, we employed a comprehensive computational drug discovery strategy to identify potential inhibitors of HER2. Our approach combined virtual screening, re-docking procedures, molecular dynamics (MD) simulations, and free energy landscape analysis using principal component analysis (PCA). From the extensive PubChem library, we initially screened 733 compounds for their binding potential to HER2, using docking scores as a primary filter. These scores ranged notably from −11.172 to −7.028 kcal/mol, indicating substantial binding capacities. Following this screening, we selected four promising compounds (PubChem CID 166029206, 166544027, 21031510, and 11712721) along with a control compound (70I) for in-depth analysis. Utilizing the Amber software suite for MD simulations, we conducted 200-nanosecond simulations to assess the interactions and binding efficiencies of these selected compounds with HER2. We analysed the molecular interactions through various parameters such as root mean square deviation (RMSD), root mean square fluctuation (RMSF), and hydrogen bond formation patterns, free binding energy calculations. The PCA-based free energy landscape analysis revealed that these compounds consistently occupied a distinct low-energy basin, indicating their high stability and strong binding affinity for the HER2. This detailed analysis provided insights into the stability and conformational dynamics of these potential inhibitors when bound to the HER2. Our findings pave the way for further experimental validation and development of these compounds as therapeutic agents in breast cancer treatment.

Geological Features and Ore Formation Pattern of Jinzhong Bauxite Mine, Shanxi Province, China

Bauxite is located in the lower part of the Benxi Formation, and the prospecting project shows that the distribution of bauxite ore bodies in the area is discontinuous, and there are differences in the thickness of the ore bodies. To have a clearer understanding of the bauxite ore bodies and metallogenic pattern in the census area, this study has made use of the prospecting project data, sample analysis results, etc., and combined with the geological and tectonic background of the area, the stratigraphic spreading characteristics of the bauxite ore body spatial spreading, ore characteristics and ore controlling factors in the area have been explored and researched. The bauxite ore bodies in the study area are stratified but the ore-bearing rock system is influenced by the Ordovician paleokarst geomorphology and intermittently distributed horizontally, which can be distinguished into three different ore bodies. The bauxite ore body and Shanxi-style iron ore are associated with hard clay ore, in which the ore minerals are mainly monohydrate duralumin. The natural ore type can be divided into dense bauxite and oolitic bauxite. Bauxite in this area mainly originated from the basal Ordovician carbonate rocks, with a combination of iron-rich and aluminum-rich layers, and is a typical carbonate rock sedimentary deposit of ancient weathering crust.

Elucidating the formation pattern and mechanism of biofouling layer regulated by pre-deposition of powdered activated carbon in gravity-driven membrane systems

Powdered activated carbon (PAC) pre-deposition promotes pollutant removal in gravity driven membrane (GDM) but diversely affects flux. This study evaluated the effects of one-time deposition (GDM 1), batch deposition (GDM 2) and no deposition (GDM 3) of PAC on the biofouling layer formation mechanism and the GDM performance. The results showed that PAC particles effectively promoted the removal of dissolved organic carbon, ammonia nitrogen and fluorescent pollutants, while also significantly reducing the concentration of extracellular polymeric substances in the biofouling layer. The stable flux in GDM 1–3 were 6.58, 7.88 and 8.61 LMH respectively. One-time deposition of PAC compromised the structure of the biofouling layer and prevented its reverse relaxation. Pollutant floc particles continuously accumulated in the space between the PAC particles, forming a dense layer with low porosity and roughness. In GDM 2, the limited amount of PAC deposited each time helped to partially maintain the intact structure of the biofouling layer, which alleviated the decline in flux. The reverse relaxation of the intact biofouling layer in GDM 3 resulted in increased porosity, which positively influenced the flux. Additionally, the abundance of Bdelloidea significantly decreased in GDM 1 and GDM 2, and more predators with low agility showed limited modification on the biofouling layer, resulting in a dense biofouling layer. In conclusion, batch deposition of PAC is more recommended as the continuously renewed PAC promote pollutant removal, and compared with one-time deposition of PAC, the reduction in biofouling layer disturbance mitigates the flux decline.

In-situ detection of electrolyte defects in lithium-ion batteries using ultrasonic imaging and analysis of formation patterns

The urgent necessity for enhanced cycling performance in lithium batteries is paramount for electric vehicles to attain broader economic advantages. However, prolonged usage and cycling often lead to electrolyte de-wetting within the battery, posing a significant risk to battery safety and lifespan reduction. A thorough understanding of the mechanisms underlying electrolyte de-wetting is pivotal for the development of long-lasting batteries. This study employs an ultrasonic non-destructive testing method to investigate changes in the internal electrolyte during battery operation. Analysis of the results found that during to the relatively higher current density and temperature near the tabs, electrolyte de-wetting is more prone to occur in these areas, with defects being more severe at the positive electrode compared to the negative electrode. Finally, these issues are addressed to provide reasonable recommendations for future battery design and optimization.

Experimental and molecular dynamics study on combustion characteristics of non-stick coal

To investigate the combustion characteristics of non-stick coal and the formation patterns of main combustion products and radicals, this study initially conducted a TG-DSC experiment of non-stick coal. Subsequently, non-stick coal was characterized and analyzed using XPS and 13C NMR experiments, and a molecular model with the formula C208H199O23N3S was constructed. Subsequently, the ReaxFF MD method was employed to simulate the combustion molecular dynamics of the non-stick coal periodic mixing model under varying oxygen content and temperature conditions. The analysis focused on elucidating the formation patterns of free and primary products during combustion. Experimental findings indicate that the combustion of non-stick coal progresses through stages, including water evaporation and desorption (30–145.65 °C), dynamic equilibrium (145.65–181.76 °C), oxygen weight gain (181.76–263.56 °C), thermal decomposition (263.56–379.14 °C), combustion (379.14–562.04 °C) and burnout (562.04–800 °C). The ignition temperature of non-stick coal was determined to be 379.14 °C. The simulation results indicate that an increase in temperature and oxygen content further enhances the relatively stable peak production of CO2. The peak increase of CO production is weaker than that of CO2. The rise in temperature also promotes the formation of H2O, while the increase in oxygen content initially enhances and subsequently inhibits the peak production of H2O. H radicals, O radicals, and OH radicals are primarily generated through the decomposition reactions of small molecular compounds or other free radicals. Free radical polymerization and the decomposition of small molecular compounds represent the primary pathways for the formation of CO, CO2, and H2O.

Early embryonic development of the German cockroach Blattella germanica

BackgroundEarly embryogenesis is characterized by dramatic cell proliferation and movement. In most insects, early embryogenesis includes a phase called the uniform blastoderm, during which cells evenly cover the entirety of the egg. However, the embryo of the German cockroach, Blattella germanica, like those of many insects within the super order Polyneoptera, does not have a uniform blastoderm; instead, its first cells condense rapidly at the site of a future germband. We investigated early development in this species in order to understand how early gene expression is or is not conserved in these insect embryos with distinct early cell behaviors.ResultsWe present a detailed time series of nuclear division and distribution from fertilization through germband formation and report patterns of expression for the early patterning genes hunchback, caudal, and twist in order to understand early polarization and mesoderm formation. We show a detailed time course of the spatial expression of two genes involved in the segmentation cascade, hedgehog and even-skipped, and demonstrate two distinct dynamics of the segmentation process.ConclusionsDespite dramatic differences in cell distribution between the blastoderms of many Polyneopteran insects and those of more well-studied developmental models, expression patterns of early patterning genes are mostly similar. Genes associated with axis determination in other insects are activated relatively late and are probably not maternally deposited. The two phases of segmentation—simultaneous and sequential—might indicate a broadly conserved mode of morphological differentiation. The developmental time course we present here should be of value for further investigation into the causes of this distinct blastoderm type.

Probing into the formation of brominated halonitromethanes from the intracellular organic matter of Anabaena during UV/chlorine disinfection

Eutrophication events in water bodies result in the release of algal organic matter, which is an essential precursor for halonitromethanes during disinfection, posing a significant threat to water quality. During UV/chlorine disinfection, the presence of bromide ion (Br−) promotes the formation of brominated halonitromethanes (Br-HNMs), which exhibit higher toxicity compared to chlorinated halonitromethanes. Nevertheless, limited studies have been conducted on the Br-HNMs formation from algal precursors during UV/chlorine disinfection in the presence of Br−. Therefore, in this study, the formation pattern and toxicity variation of Br-HNMs from the intracellular organic matter (IOM) of anabaena during UV/chlorine disinfection was investigated. The results showed that monobromonitromethane, bromochloronitromethane, and bromodichloronitromethane could be detected during UV/chlorine disinfection. When the Br− concentration raised, the total concentration and toxicity of Br-HNMs exhibited an increase followed by a decline. Additionally, the concentration and toxicity of three Br-HNMs were promoted by increasing UV intensity, free chlorine dosage, and anabaena concentration but inhibited by increasing pH. Based on the experiment results, possible pathways for Br-HNMs formation from anabaena IOM in the presence of Br− were deduced. Moreover, anabaena IOM could also be converted to Br-HNMs during UV/chlorine disinfection of actual water, with a formation pattern similar to that found in distilled water. This research offers valuable insights into Br-HNMs formation from algal-containing waters.

Identification and comparison of protein composition of biofilms in response to EGCG from Enterococcus faecalis and Staphylococcus lugdunensis, which showed opposite patterns in biofilm-forming abilities

Bacterial biofilm is resistant to conventional antibiotic treatments, leading to complications associated with many infection-related human diseases. Epigallocatechin Gallate (EGCG), a phenolic catechin enriched in green tea, is recognized for its anti-bacterial and anti-biofilm activities. In this study, we examined the protein components of the biofilms formed in the absence or presence of EGCG using Enterococcus faecalis and Staphylococcus lugdunensis, which had shown opposing patterns in biofilm formation. A clustering heatmap revealed that the two microorganisms expressed the different protein sets in response to EGCG. Proteins that were noticeably upregulated included those associated with stress responsiveness and gluconeogenesis in E. faecalis, and gene modification in S. lugdunensis. Conversely, downregulated proteins were related to tRNA-modifying enzyme activity in E. faecalis, and anabolic metabolism in S. lugdunensis. Among the proteins identified only in EGCG-responsive biofilms, enzymes involved in de novo purine biosynthesis were enriched in E. faecalis, while proteins likely to cause DNA instability and pathogenicity changes were abundantly present in S. lugdunensis. The classification based on gene ontology (GO) terms by microorganism exhibited that metabolic process or catabolic activity was at the top rank in E. faecalis with more than 33 proteins, and in S. lugdunensis, localization or transport was highly ranked with 4 proteins. These results support the hypothesis that EGCG might cause different cellular programs in each microorganism. Finally, comparison of the proteomes between two groups that form biofilms to similar extents discovered that 2 proteins were commonly found in the weak biofilm-forming groups (E. faecalis and EGCG-responding S. lugudunensis), whereas 9 proteins were common among the strong biofilm-forming groups (S. lugdunensis and EGCG-responding E. faecalis). It was suggested that these proteins could serve as potential indicators to detect the presence and predict the extent of biofilm formation by multiple microorganisms. Taken all together, proteomics data and analyses performed in this study provided useful and new information on the proteins embedded in the biofilms formed at the specific conditions, which can aid in diagnosis and the development of tailored treatment strategies.

OMIBONE: Omics-driven computer model of bone regeneration for personalized treatment

Treatment of bone fractures are standardized according to the AO classification, which mainly refers to the mechanical stabilization required in a given situation but neglect individual differences due to patient's healing potential or accompanying diseases. Specially in elderly or immune-compromised patients, the complexity of individual constrains on a biological as well as mechanical level are hard to account for. Here, we introduce a novel framework that allows to predict bone regeneration outcome using combined proteomic and mechanical analyses in a computer model. The framework uses Ingenuity Pathway Analysis (IPA) software to link protein changes to alterations in biological processes and integrates these in an Agent-Based Model (ABM) of bone regeneration. This combined framework allows to predict bone formation and the potential of an individual to heal a given fracture setting. The performance of the framework was evaluated by replicating the experimental setup of a mouse femur fracture stabilized with an intramedullary pin. The model was informed by serum derived proteomics data. The tissue formation patterns were compared against experimental data based on x-ray and histology images. The results indicate the framework potential in predicting an individual's bone formation potential and hold promise as a concept to enable personalized bone healing predictions for a chosen fracture fixation.

Transcriptomic Analysis Reveals the Mechanism of Color Formation in the Peel of an Evergreen Pomegranate Cultivar 'Danruo No.1' During Fruit Development.

Pomegranate (Punica granatum L.) is an ancient fruit crop that has been cultivated worldwide and is known for its attractive appearance and functional metabolites. Fruit color is an important index of fruit quality, but the color formation pattern in the peel of evergreen pomegranate and the relevant molecular mechanism is still unknown. In this study, the contents of pigments including anthocyanins, carotenoids, and chlorophyll in the peel of 'Danruo No. 1' pomegranate fruit during three developmental stages were measured, and RNA-seq was conducted to screen key genes regulating fruit color formation. The results show that pomegranate fruit turned from green to red during development, with a dramatic increase in a* value, indicating redness and anthocyanins concentration, and a decrease of chlorophyll content. Moreover, carotenoids exhibited a decrease-increase accumulation pattern. Through RNA-seq, totals of 30, 18, and 17 structural genes related to anthocyanin biosynthesis, carotenoid biosynthesis and chlorophyll metabolism were identified from differentially expressed genes (DEGs), respectively. Transcription factors (TFs) such as MYB, bHLH, WRKY and AP2/ERF were identified as key candidates regulating pigment metabolism by K-means analysis and weighted gene co-expression network analysis (WGCNA). The results provide an insight into the theory of peel color formation in evergreen pomegranate fruit.

Quantum Information Patterns Between Atoms in a Molecule.

Quantum information theory provides a powerful toolbox of descriptors that characterize many-electron systems based on quantum information patterns between open quantum systems. Despite the wealth of insights gained in the condensed matter community, the use of these descriptors to study interactions between atoms in a molecule remains limited. In this study, we develop a quantum information framework for molecules that characterizes the quantum information patterns between quantum atoms as defined in the Quantum Theory of Atoms in Molecules. We show that quantum information analyses capture key properties of quantum atoms and how they interact with their molecular environment. Additionally, we show that the presence of bond critical points can remain invariant despite large changes in the quantum information patterns between the quantum atoms. Our findings indicate that quantum information theory can shed a new light on molecular electronic structure.

Interference Between S. Aureus and P. Aeruginosa Clinical Isolates

General Background: Understanding microbial interactions between Pseudomonas aeruginosa and Staphylococcus aureus is crucial for clinical infections, as they often coexist and influence each other's growth and virulence. Specific Background: Both organisms are known for their ability to form biofilms and exhibit multidrug resistance (MDR), complicating treatment strategies in hospitalized patients. Knowledge Gap: Previous studies have explored the virulence of P. aeruginosa and S. aureus, but there is limited understanding of their direct in vitro interactions, particularly in protease and lipase production. Aims: The study examined the interaction between P. aeruginosa and S. aureus isolates in hospitalized patients' sputum, urine, and blood samples, focusing on virulence factors, biofilm formation, and antibiotic resistance patterns. Results: In Diyala, Iraq, 50 clinical isolates showed P. aeruginosa as protease producers, lipase producers, and biofilm producers, with significant MDR phenotypes in both species. Novelty: This study highlights the ability of P. aeruginosa to produce staphylolysin, offering novel insights into the antagonistic mechanisms that may suppress S. aureus in co-infections. Implications: The study emphasizes the significance of understanding microbial interactions in clinical infections, particularly in biofilm-associated MDR infections, to improve treatment outcomes and guide more effective therapeutic approaches. Highlights: P. aeruginosa staphylolysin inhibits S. aureus growth in vitro. Both bacteria produce biofilms and exhibit multidrug resistance. Microbial interactions impact infection severity and treatment strategies. Keywords: Microbial interactions, Pseudomonas aeruginosa, Staphylococcus aureus, Biofilm, Multidrug resistance