Search Results (89)

The application of an ultrafiltration (UF) process with periodic membrane cleaning with the use of alkaline detergent solutions was proposed for the recovery of wash water from car wash effluent. In order to test the resistance of the membranes to the degradation caused by the cleaning solutions, a pilot plant study was carried out for almost two years. The installation included an industrial module with FP100 tubular membranes made of polyvinylidene fluoride (PVDF). The module was fed with synthetic effluent obtained by mixing foaming agents and hydrowax. To limit the fouling phenomenon, the membranes were cleaned cyclically with P3 Ultrasil 11 solution (pH = 11.7) or Insect solution (pH = 11.5). During plant shutdowns, the membrane module was maintained with a sodium metabisulphite solution. Changes in the permeate flux, turbidity, COD, and surfactant rejection were analysed during the study. Scanning electron microscopy (SEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy (FTIR) analysis were used to determine the changes in the membrane structure. As a result of the repeated chemical cleaning, the pore size increased, resulting in a more than 50% increase in permeate flux. However, the quality of the recovered wash water did not deteriorate, as an additional separation layer was formed on the membrane surface due to the fouling phenomenon. Full article

(1) Background: The larvae of Dioryctria sylvestrella typically bore into the shoots and cones of Pinus koraiensis, increasing tree breakage risk and reducing cone yield. (2) Methods: Five Beauveria bassiana strains were evaluated for virulence against fourth-instar larvae. And the levels of T-AOC and MDA in the larvae infected by each strain were measured. To assess larval responses to different strains, we measured the activities of six enzymes (SOD, CAT, POD, PPO, CarE, GST) and the levels of GSH and H₂O₂ in larvae treated with each strain. Additionally, the infection process of highly pathogenic B. bassiana in larvae was explored using scanning electron microscopy (SEM). (3) Results: Strain CGMCC3.2055 demonstrated the highest toxicity to larvae, achieving a cumulative corrected mortality of 80.56% on the 4th day and an LT₅₀ of 3.248 days. The T-AOC of larvae treated with strain CGMCC3.2055 was inhibited within 48 h. The relative MDA content in this group was significantly higher than that in other strain-treated groups at 6, 12, and 24 h. In Bb01-treated larvae, H₂O₂ accumulation at 6 and 24 h post-infection was influenced by POD activity rather than GSH levels; in BbZ1-treated larvae, the activities of CAT and POD were upregulated at 6 and 36 h, while the activity of SOD was downregulated, but the content of H₂O₂ increased significantly, resulting in accumulation; in CFCC81428-treated larvae, a decline in T-AOC coincided with substantial H₂O₂ accumulation over 48 h, while a concomitant increase in GSH content bolstered tolerance to lethal oxidative damage; in CGMCC3.2055-treated larvae, H₂O₂ only accumulated significantly at 24 and 48 h, yet upregulated CAT and POD were insufficient to effectively scavenge the excess H₂O₂; and in bio-21738-treated larvae, SOD-driven dismutation generated substantial H₂O₂ from 12 to 48 h, leading to pronounced accumulation from 6 to 48 h, yet limited upregulation of POD (only at 6 and 12 h) and CAT (only at 12 and 48 h) were insufficient to mitigate H₂O₂ buildup. PPO activity was upregulated within 48 h in all treatment groups except for BbZ1, where no upregulation was observed at 12 and 48 h. GST activity was upregulated in all treatment groups except for CGMCC3.2055, where a downregulation was observed at 12 h post-infection. CarE activity was significantly upregulated within 48 h in both CFCC81428 and CGMCC3.2055 groups; in the Bb01 group, CarE was upregulated only at 6 and 48 h; in the BbZ1 group, CarE was downregulated only at 48 h; and in the bio-21738 group, CarE showed no upregulation at 24 and 48 h. Through SEM, the infection process of the strain CGMCC3.2055 on the surface of the larvae was further determined, which mainly included adhesion, the appearance of bud-like protrusions, the growth of germ tubes along the epidermis and penetration of the epidermis, as well as the colonization of the strain and its emergence from the surface of the larvae. (4) Conclusions: This study first screened the highly pathogenic B. bassiana strain CGMCC3.2055 by evaluating its virulence to larvae and post-infection T-AOC and MDA levels. It also clarified the strain’s infection process and the larvae’s immune responses to various strains. Full article

The parking ratchet is an important safety component of the car. Cracking occurs in the grinding surface during quenching and grinding processes after carburizing; thus, the goal of this research is to clarify the key cracking cause of the parking ratchet. Optical microscopy (OM), scan electronic microscope (SEM), energy dispersive spectroscopy (EDS), X-ray stress analyzer, etc., were used to systematically test and analyze the cracking cause. The results show that the microstructure of the parking ratchet with cracks after carburizing and quenching is normal, the residual stress of the surface is normal, with no oxide and decarburized layer within the crack areas, without burning during grinding, while it was found that oxide inclusions existed on the area of the crack, which is different from the normal specimens. Hence, a conclusion can be drawn that the cracking cause on the surface of the parking ratchet results from the oxide inclusions in the raw material. This study provides a feasible direction for the failure analysis and control of the cracks on parking ratchets during the manufacturing process. Full article

B Cell Maturation Antigen (BCMA) has gained considerable attention as a target in directed therapies for multiple myeloma (MM) treatment, via immunoglobulin-based bispecific T cell engagers or CAR T cell strategies. We describe the development of alternative, non-immunoglobulin BCMA-recognising affinity proteins, based on the small (58 aa) three-helix bundle affibody scaffold. A first selection campaign using a naïve affibody phage library resulted in the isolation of several BCMA-binding clones with different kinetic profiles. One clone showing the slowest dissociation kinetics was chosen as the template for the construction of two second-generation libraries. Characterization of output clones from selections using these libraries led to the identification of clone 1-E6, which demonstrated low nM affinity to BCMA and high thermal stability. Biosensor experiments showed that 1-E6 interfered with the binding of BCMA to both its natural ligand APRIL and to the clinically evaluated anti-BCMA monoclonal antibody belantamab, suggesting overlapping epitopes. A fluorescently labelled head-to-tail homodimer construct of 1-E6 showed specific binding to the BCMA⁺ MM.1s cell line in both flow cytometry and fluorescence microscopy. Taken together, the results suggest that the small anti-BCMA affibody 1-E6 could be an interesting alternative to antibody-based affinity units in the development of BCMA-targeted therapies and diagnostics. Full article

Enzyme catalysis represents a promising approach for sustainable chemical synthesis, yet its industrial applications face limitations due to the inefficient regeneration and high cost of essential cofactors, such as adenosine-5′-triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH). While natural metabolic systems efficiently recycle cofactors through spatially organized enzymes, replicating this efficiency in vitro remains challenging. Here, we prepare a five-enzyme condensate system using liquid–liquid phase separation (LLPS) mediated by intrinsically disordered proteins (IDPs). By colocalizing a carboxylic acid reductase from Norcadia iowensis (NiCAR) with a reductive aminase from Aspergillus oryzae (AspRedAm) and three cofactor-regenerating enzymes, we generated a phase-separated catalytic condensate that enhanced ATP and NADPH recycling efficiency by 4.7-fold and 1.9-fold relative to free enzymes, respectively. Catalytic performance was correlated with the extent of phase separation, as confirmed by fluorescence microscopy, which revealed clear enrichment of ATP and NADPH within the condensates. This proximity effect enabled efficient cofactor turnover in the one-step reaction, achieving substrate conversion above 90% within 6 h and enhancing the space–time yield (STY) of the chiral imines 1.6-fold, with only one-fifth of the standard cofactor load. This approach creates a scalable and economic tool for performing multienzyme cascade reactions in vitro that are driven by the efficient recycling of multiple cofactors. Full article

This study uses the melt compounding method to recycle polypropylene-based car bumper waste (PP-CBW) in order to produce nanocomposite films for mulch application. The nanocomposite films were compounded by mixing virgin linear low-density polyethylene (LLDPE) with PP-CBW at a constant ratio of 4:1 in the presence of different percentages of nanofillers. Nanocomposites reinforced with nanoclays were compatibilized with an anhydride grafted polyethylene (PE-g-MAH), at a constant compatibilizer-to-clay ratio equal to 3, to improve the adherence between the nonpolar matrix and the hydrophilic nanoclay and acrylic paint present in the car bumper. An extruder with a corotating twin screw was used to produce blends of different compositions. To create nanocomposite films, the mixtures were further processed in a blown film extruder. The effect of the presence of nanoclays on the barrier, thermal, and mechanical properties of the nanocomposite films was investigated. The dispersion of clay layers in the matrix was examined by atomic force microscopy (AFM). The results indicate that 3 wt% of clay loading maximized the tensile strength in the transverse direction (TD) and machine direction (MD). A 1 wt% clay loading increased the MD tear resistance by 66% and manifested an optimum dart impact strength. Significant improvements in thermal and barrier properties were also achieved in the presence of 3 wt% clay loading. Full article

Transport and vehicle traffic are closely connected with particulate matter (PM) pollution, inducing various fractions into the atmosphere, some of them forming significant deposits on the surface of the car. They are washed away during carwash-inducing slurries collecting the PM deposits, which are characteristic of a large area. Crystalline PM matter was investigated by XRD coupled with polarized optical microscopy (POM). Organic matters were investigated by Fourier-Transform Infrared spectrometry (FTIR) and gas chromatography, GC-MS. Their microstructure and elemental composition were investigated by SEM-EDX. The crystalline features contain mainly quartz, calcite, and clay (muscovite and kaolinite) particles having traces of goethite and lepidocrocite. Slurry particle size distribution was established by sieving on the following meshes: 63 µm, 125 µm, 250 µm, 500 µm, 1000 µm, 2000 µm, and 4000 µm. Coarse fractions of 250–4000 μm are dominated by quartz and calcite particles. The quartz and calcite amount decreases with particle size, while the muscovite and kaolinite amount increases in the finest fractions of 0–125 μm. Organic matter was evidenced, firstly, by FTIR spectroscopy, revealing mostly CH₂; C=O, and NH₄ bonds that are more intense for the fine particulate fractions. The organic deposits form mainly amorphous crusts associated with micro- and nano-plastic particles related to the phthalates and traces of the washing detergents. Atomic Force Microscopy revealed their size range between 60 and 90 nm and evidenced nanoparticles within samples. The nanofractions adhere to the bigger particles in humid environments, assuring their immobilization to reduce their hazardous potential. Carwash slurry blending with fertile soil ensures proper grass seed germination and growth at mixtures of up to 60% slurry, allowing its sustainable reconversion as soil for landfill and dump rehabilitation, preventing the PM emission hazard. Blended compositions containing more than 60% slurry have noxious effects on the grass seeds, inhibiting their germination. Full article

Noise level and atmospheric pollutants such as particulate matter (PM) and combustion gases depend on car traffic. A highly circulated area in Cluj-Napoca City (Romania) was investigated based on sustainable principles. The noise level at the source was about 77 dB due to intense traffic of 214 units/10 min including cars, buses, trucks and pedestrians. It decreased slowly to 62 dB in the proximity of the first wall from the roadside (20 m distance) and significantly to about 50 dB beyond the buildings near the road (135 m from the source). The noise level was correlated with a high pollutant emission at the source: 25 µg/m³ (PM_2.5), 45 µg/m³ (PM₁₀) and 1.023 µg/m³ (total volatile organic compounds (TVOCs)). The PM₁₀ level decreased to 38 µg/m³, while PM_2.5 remained at a high level at 22 µg/m³ and TVOC slightly decreased to 0.974 µg/m³ at the distance of 10 m from the road. The PM_2.5 and PM₁₀ levels decreased significantly to 5 µg/m³ (PM₁₀) and 18 µg/m³ (PM_2.5) at a distance of 135 m from the road, and the TVOC level also decreased significantly to about 0.705 µg/m³. The PM crystalline structure was investigated by XRD coupled with mineralogical microscopy. Microstructure and elemental composition were assessed via high-resolution SEM coupled with EDS spectroscopy. It was found that PM_2.5 was dominated by the finest clay fraction (e.g., kaolinite and muscovite), while PM₁₀ was dominated by quartz and calcite. A large amount of organic matter was found adsorbed onto the finest particles by FTIR spectroscopy. The correlation between PM emissions and sound intensity indicates that intense noise extended for a long time facilitates the ultra-structural PM fraction sustentation into the atmosphere. A large number of clay nanoparticles (kaolinite 40 nm and muscovite 60 nm) were detected by AFM in the samples collected at the noise source, becoming sparser at a distance of 135 m from the source. Full article

Rosmarinic acid (RA) is a bioactive phenolic compound prevalent in various medicinal plants, renowned for its significant pharmacological properties. This study aims to optimise the extraction conditions of this compound from Rosmarinus officinalis L. using the response surface methodology (RSM) with a three-variable, three-level Box–Behnken design. Optimising the parameters for supercritical CO₂ (scCO₂) extraction focused on pressure (150 to 350 bar), temperature (40 to 80 °C), and co-solvent weight percentage (5 to 15% ethanol), evaluating their impact on overall yield and RA content. The optimal conditions determined were a pressure of 150 bar, a temperature of 80 °C, and 15% ethanol, yielding a total extract of 21.86 ± 1.55%, with an RA content of 3.43 ± 0.13 mg/g dry matter (DM). Scanning electron microscopy revealed that the scCO₂ treatment induced microcracks on the surface of the rosemary powder, enhancing the fluid’s ability to penetrate the plant matrix. By employing the combined scCO₂-Soxhlet method, the RA content increased to 5.78 mg/g DM. Furthermore, the final extract obtained using the Soxhlet post-scCO₂ treatment contained only trace amounts of carnosic acid (0.38 ± 0.10 mg/g DM) and carnosol (0.38 ± 0.20 mg/g DM), compared to the crude extract obtained solely with Soxhlet, which exhibited significantly higher concentrations of 8.45 ± 2.98 mg/g DM of carnosol and 16.67 ± 0.94 mg/g DM of carnosic acid. This work highlighted an innovative extraction strategy based on the coupling of scCO₂ and Soxhlet, which significantly increased RA content while reducing concentrations of other compounds such as CA and CAR. This approach makes it possible to produce RA-enriched extracts, offering considerable potential for future large-scale applications and commercialisation. Full article

This article examines contacting by means of ultrasonic welding between a cast aluminum winding and a copper conductor of a wheel hub drive for a passenger car. The effect of thermal stress on the formation and growth of intermetallic phases (IMC) in the contact is analyzed. By using microscopy, the growth constant under the specific load conditions can be identified with the help of the parabolic time law and offer a possibility for predicting the service life of the corresponding contacts. As a result, it can be stated that the increase in electrical resistance of the present contact at load temperatures of 120 °C, 150 °C, and 180 °C does not reach a critical value. The growth rates of the IMC also show no critical tendencies at the usual operating temperatures (120 °C and 150 °C, e.g., at 150 °C = 4.59 × 10⁻⁷ μm²/s). The activation energy calculated using the Arrhenius plot of 155 kJ/mol (1.61 eV) can be classified as high in comparison to similar studies. In addition, it was found that future investigations of the IMC growth of corresponding electrical contacts should rather be carried out with electric current. The 180 °C sample series were carried out in the oven and with electric current; the samples in the oven did not show clear IMC, while the samples exposed to electric current already showed IMC under the microscope. Full article

The development of ultrafiltration (UF) polymeric membranes with high flux and enhanced antifouling properties bridges a critical gap in the polymeric membrane fabrication research field. In the present work, the preparation of novel PES membranes incorporated with carrageenan (CAR), which is a natural polymer derived from edible red seaweed, is reported for the first time. The PES/CAR membranes were prepared by using the nonsolvent-induced phase separation (NIPS) method at 0.1–4.0 wt.% CAR loadings in the casting solutions. The use of dimethylsulfoxide (DMSO), which is a bio-based and low-toxic solvent, is reported. Scanning electron microscopy, atomic force microscopy, water contact angle, porosity, and zeta potential measurements were used to evaluate the surface morphology, structure, pore size, hydrophilicity, and surface charge of the prepared membranes. The filtration performance of PES/CAR membranes was tested with bovine serum albumin (BSA) solutions. It was shown that CAR incorporation in the casting solutions notably increased hydrophilicity, porosity, pore size, surface charge, and fouling resistance of the prepared membranes compared with plain PES membranes due to the hydrophilic nature and pore-forming properties of CAR. The PES/CAR membranes showed a significant reduction in irreversible and total fouling during filtration of BSA solutions by 38% and 32%, respectively, an enhancement in the flux recovery ratio by 20–40%, and an improvement in mechanical properties by 1.5-fold when compared with plain PES membranes. The findings of the present study indicate that CAR can be used as a promising additive for the development of PES UF membranes with enhanced properties and performance for water treatment applications. Full article

Nanofibrous dressing materials with an antitumor function can potentially inhibit recurrence of melanoma following the surgical excision of skin tumors. In this study, hydrolyzed polyacrylonitrile (hPAN) nanofibers biofunctionalized with L-carnosine (CAR) and loaded with bio (CAR)-synthesized zinc oxide (ZnO) nanoparticles, ZnO/CAR-hPAN (hereafter called ZCPAN), were employed to develop an antimelanoma wound dressing. Inspired by the formulation of the commercial wound healing Zn-CAR complex, i.e., polaprezinc (PLZ), for the first time, we benefitted from the synergy of zinc and CAR to create an antimelanoma nanofibrous wound dressing. According to scanning electron microscopy (SEM) images, ultrafine ZnO nanoparticles were homogenously distributed throughout the nanofibrous dressing. The ZCPAN nanofiber mat showed a significantly higher toughness (18.7 MJ.m⁻³ vs. 1.4 MJ.m⁻³) and an enhanced elongation at break (stretchability) compared to the neat PAN nanofiber mat (12% vs. 9.5%). Additionally, optical coherence elastography (OCE) measurements indicated that the ZCPAN nanofibrous dressing was as stiff as 50.57 ± 8.17 kPa which is notably larger than that of the PAN nanofibrous dressing, i.e., 24.49 ± 6.83 kPa. The optimum mechanical performance of the ZCPAN nanofibers originates from physicochemical interaction of CAR ligands, hPAN nanofibers, and ZnO nanoparticles through hydrogen bonding, electrostatic bonding, and esterification, as verified using ATR-FTIR. An in vitro cell viability assay using human skin melanoma cells implied that the cells are notably killed in the presence of the ZCPAN nanofibers compared to the PAN nanofibers. Thanks to ROS generating ZnO nanoparticles, this behavior originates from the high reactive oxygen species (ROS)-induced oxidative damage of melanoma cells, as verified through a CellROX assay. In this regard, an apoptotic cell response to the ZCPAN nanofibers was recorded through an apoptosis assay. Taken together, the ZCPAN nanofibers induce an antimelanoma effect through oxidative stress and thus are a high potential wound dressing material to suppress melanoma regrowth after surgical excision of skin tumors. Full article

Metastasis in oncological diseases remains one of the main reasons for negative prognosis regarding treatment. Any new data on the biophysical and biochemical characteristics of circulating metastatic cells will help to develop a concept for antimetastatic therapy. In this study, we found a number of differences in the spectroscopic and morphological features of circulating metastatic cells. FT-IR and Raman spectra cultivated by adhesive and de-adhesive methods (with the latter used as a model for metastatic cells) have shown spectroscopic features, namely in FT-IR spectra in the region of CH stretching vibrations, which are associated with structural rearrangements in the cell membrane, as well as changes in the intensity and position of the PO₂⁻ group vibration bands correlated with proliferative activity. The spectral features in the regions of OH stretching and Amide I vibrations as well as other spectral markers of the metastatic cells grown under different cultivation conditions were derived. Raman spectra showed a redistribution of the amino acid Tyr/Trp (tryptophan to tyrosine) ratio and in Tyr doublet intensity in the region of 500–900 cm⁻¹, as well as varying glycogen levels in different cells. The spectroscopic markers are in accordance with biochemical data. CARS and confocal optical microscopy were applied to determine the state of the cells and the F-actin expression level, which turned out to be higher for adhesive cells in comparison with de-adhesive cells. The shape and the morphological properties of the cells differ drastically. The correlation of vibrational markers with biochemical data and the cytofluorometric method was discussed. Full article

Poor sanitation, improper food handling, limited access to safe drinking water sources, and limited access to healthcare services contribute to a high prevalence of infections caused by soil-transmitted helminths (STHs) among the BaAka Pygmies, an indigenous community living in Central Africa. The aim of this study was to determine the rates of STH infections in the BaAka people inhabiting the rain forests of the south-western parts of the Central African Republic (CAR) as well as to examine the validity of biannual deworming with a single dose of albendazole 400 mg in high-risk communities exposed to extreme environmental conditions. The study was conducted in August 2021 and involved a sample of 49 BaAka Pygmies inhabiting the rain forest of the Sangha-Mbaéré Prefecture, CAR. The study consisted of collecting single stool samples from each participant and examining the samples for intestinal parasites by light microscopy methods. The collected samples were fixed in SAF fixative and next transported from Africa to Europe, where they were analyzed by light microscopy using three different diagnostic methods (direct smear in Lugol’s solution, the Fülleborn’s flotation, the Kato–Katz thick smear) at the Department of Epidemiology and Tropical Medicine in Gdynia, Poland. Microscopic examination found that 61.2% of the study group were infected with at least one helminthic species. The parasitological screening found invasions with four different species of nematodes, of which hookworm invasions were the most prevalent. The study results demonstrated that although the WHO-recommended mass deworming, which is provided to the BaAka Pygmies in healthcare centers set up on the premises of catholic missions, can effectively reduce the number of infections with soil-transmitted helminths, the prevalence of STH infections remains high in the region. The study findings suggest that in order to contain the spread of STHs in the local community, it will be necessary to implement additional preventive measures, apart from only conducting mass deworming programs. Full article

In this study, we fabricated Ti-Cu-based friction composites containing waste-metal (Ti, CuZn, stainless steel (SSt), MgAl), Al₂O₃ due to improving properties and its good compatibility with copper and graphene nanoplatelets as reinforcement and lubricant component, using planetary ball mill and technique based on Spark Plasma Sintering (SPS). Understanding the wear behaviour of such engineered friction composites is essential to improve their material design and safety, as these materials could have the potential for use in public and industrial transportation, such as high-speed rail trains and aircraft or cars. This is why our study is focused on wear behaviour during friction between function parts of devices. We investigated the composite materials designed by us in order to clarify their microstructural state and mechanical properties. Using different loading conditions, we determined the Coefficient of Friction (COF) using a ball-on-disc tribological test. We analysed the state of the samples after the mentioned test using a Scanning Electron Microscope (SEM), then Energy-Dispersive X-ray Spectroscopy (EDS), and confocal microscopy. Also, a comparative analysis of friction properties with previously studied materials was performed. The results showed that friction composites with different compositions, despite the same conditions of their compaction during sintering, can be defined by different wear characteristics. Our study can potentially have a significant contribution to the understanding of wear mechanisms of Ti-Cu-based composites with incorporated metal-waste and to improving their material design and performance. Also, it can give us information about the possibilities of reusing metal-waste from different machining operations. Full article