Search Results (6,768)

Head and neck cancers (HNCs) are often diagnosed late, leading to poor prognosis. Chronic inflammation, particularly periodontitis, has been linked to carcinogenesis, but systemic inflammatory markers remain underexplored. This study was the first to examine whether elevated C-reactive protein (CRP) can serve as a cost-effective adjunct in HNC risk assessment, alongside oral health indicators. A retrospective cohort study analysed 23,742 hospital records (4833 patients, 2015–2022) from the University Hospital of Debrecen. HNC cases were identified using ICD-10 codes, with CRP and periodontitis as key predictors. Kaplan–Meier survival analysis, log-rank tests, and Weibull regression were used to assess risk, with model performance evaluated via AIC/BIC and ROC curves. Periodontitis was significantly associated with HNC (HR 5.99 [1.96–18.30]), while elevated CRP (>15 mg/L) independently increased risk (HR 4.16 [1.45–12.00]). Females had a significantly lower risk than males (HR 0.06 [0.01–0.50]). CRP may serve as a cost-effective, easily accessible biomarker for early HNC detection when combined with oral health screening. Integrating systemic inflammation markers into HNC risk assessment models could potentially improve early diagnosis in high-risk populations. Full article

Tobacco smoking and electronic cigarette (EC) use are associated with elevated levels of particulate matter (PM) and nicotine in indoor environments. This study assessed filtration and nicotine capture efficiency of untreated and citric acid-treated high efficiency particulate air (HEPA) filters from two manufacturers, “on-brand” (original) and “off-brand” (replacement). When challenged with salt aerosol, the filtration efficiency (FE) (Mean ± RSD) of original HEPA filters (99.9% ± 0.1) was significantly higher than replacements (94.4% ± 1.7), but both were significantly below the HEPA designation of 99.97%. No significant differences in FE were observed between treated and untreated HEPA filters. All filters had lower FE for EC aerosol compared to salt aerosol, especially among replacement filters. Nicotine capture efficiency was significantly higher in citric acid-treated HEPA filters for originals (99.4% ± 0.22) and replacements (99.0% ± 1.07) compared to untreated originals (57.4% ± 2.33) and replacements (42.0% ± 14.20). This study demonstrated that our citric acid treatment of HEPA filters was effective and efficient at capturing airborne nicotine and did not affect the FE for PM. Use of citric acid-treated HEPA filters would be an effective exposure reduction strategy for both nicotine and PM in indoor settings. Full article

This study examines the treatment of industrial wastewater generated during vibro-abrasive steel and Zn-Al alloy parts machining in a Polish metal-processing plant. The machining process uses grinding fluids, which are sent for disposal after becoming saturated with contaminants, incurring high costs. A two-stage filtration process was investigated: an initial bag filtration (pore size 5 µm) followed by a low-pressure (4 bar) ultrafiltration with polyacrylonitrile membranes (30 kDa cut-off). The studies were carried out on a laboratory scale in a cross-flow system using a batch configuration. The initial filtrate flux was 0.116 mL min⁻¹ cm⁻² and 0.050 mL min⁻¹ cm⁻² for Zn-Al alloy and the steel wastewater, respectively. Key physicochemical parameters, including turbidity, COD, and TOC, were analysed for raw wastewater, feed, retentate, and permeate. Significant reductions in contaminant concentrations were achieved, with comparable total efficiencies for both the wastewaters tested. The reductions in turbidity, COD, TOC, anionic surfactants, total phosphorus and non-ionic surfactants ranged from 80% to almost 100%. A complete removal of total suspended solids was achieved. The novelty of this research lies in applying polyacrylonitrile flat-sheet membranes to treat wastewater from vibratory machining of ferrous and non-ferrous materials and recycle reclaimed water, which has not been systematically explored in previous studies. The study demonstrates the potential of low-pressure membrane filtration for wastewater recycling, offering insights into environmentally friendly and energy-efficient management of industrial wastewater. Full article

Background/Objectives: While there are several debates on en bloc renal transplants and pediatric donors regarding the efficacy and concern for renal mass, multiple studies have supported the notion that transplanting pediatric en bloc kidneys produces comparable results in contrast to single kidneys from living or deceased donors. Methods: This case series included a retrospective analysis of a university medical center, primarily focused on comparing the post-operative outcomes between recipients of pediatric and adult en bloc kidneys, which are horseshoe kidneys, from deceased donors and recipients of single adult kidneys from living or deceased donors. Results: This study demonstrated that the post-operative results in recipients of pediatric en bloc kidneys consisting of serum creatinine and estimated glomerular filtration rate (eGFR) values were lower and higher, respectively, and had a comparable improvement in kidney function at post-transplant, 1-week, 1-month, 3-months, and 1-year post-op marks. Conclusions: Our center data and outcomes indicate that en bloc kidney transplantation from pediatric donors yields comparable results to that of single kidney transplantations from living and deceased donors. Full article

Tangential flow microfiltration is easily adapted for batch and continuous bioreactor clarification. The permeate can be introduced directly to the subsequent capture step. However, the commercial use of tangential flow filtration (TFF) is limited by membrane fouling, leading to a compromised performance. Here, we explored the possibility of reducing membrane fouling by integrating a hydrocyclone as the primary clarification operation. The overflow from the hydrocyclone was introduced directly as the feed to the microfiltration module. Chinese hamster ovary cells were used as the feed stream to investigate the feasibility of this integrated process. A range of cell viabilities from 0% (cell lysate) to 96% were investigated. The cell densities ranged from 0.9 to 10 million cells per mL. Two commercially available hollow fiber microfiltration membranes were used, an essentially symmetric membrane and a reverse asymmetric membrane where the more open support structure faced the feed stream. The reverse asymmetric membrane was more resistant to fouling in the absence of an integrated hydrocyclone. Integrating a hydrocyclone led to a reduction in the flux decline for the symmetric membrane, but did not affect the performance of the reverse asymmetric membrane. The careful choice of membrane morphology and pore size is important when designing an integrated process. Full article

Multiple cyclones working in series are sufficient for heavy separation tasks at the cost of significant energy consumption. The majority of researchers conducting optimization studies on multiple cyclones have attempted to find the best possible compromise between pressure drop and collection efficiency by optimizing the geometry of the cyclones. In a departure from this approach, we report a novel design. Using the proposed method, exit gas is divided into dirty and clean gas by inserting a secondary vortex finder (SVF) into the primary vortex finder (PVF) of the previous cyclone. The dirty gas flows into the succeeding cyclone, whereas the clean gas passes over the succeeding cyclone and directly flows into the device farther behind. Methodologically, the separation performance was tested experimentally, and computational fluid dynamics (CFD) simulations were employed. The Reynolds Stress Model (RSM) for turbulence and the Discrete Phase Model (DPM) were used to simulate the turbulent two-phase flow within the gas–solid separator, capturing the three-dimensional, transient, and turbulent characteristics of the flow. Our performance test results showed that the new series configuration clearly reduces energy consumption while not hindering overall efficiency. The CFD simulation was used to optimize the SVF’s diameter and length. The results indicated that having an SVF with optimal dimensions significantly enhances the vortex flow in the separation space and thus improves the efficiency of the previous cyclone. In addition, an equation was established that describes the volume of gas flowing into a succeeding cyclone. Full article

Efficient dye sieving and salt separation can facilitate the recycling of valuable resources in textile wastewater treatment. This study focuses on developing a high-performance nanofiltration membrane (NF) by co-depositing activated polydopamine (O-PDA), oxidized with KMnO₄, and polyethyleneimine (PEI) onto a polysulfone support membrane (PSF), thereby enabling effective dye sieving and salt separation. Due to the high hydrophilicity of PDA and the formation of high molecular polymers after oxidation, it was anticipated that O-PDA would crosslink the PEI layer, providing rapid permeating channels. Filtration experiments demonstrated that the formation of O-PDA significantly enhanced the salt retention rate of nanofiltration membranes, achieving a nearly threefold increase in NaCl retention from 15% to 45.7%. It was observed that the retention performance of O-PDA could be adjusted by controlling its loading or oxidation level. Furthermore, despite a notable reduction in permeability, the dye removal efficiency of the O-PDA/PEI membrane increased substantially to 99.5%. Long-term filtration experiments also confirmed both the stability and anti-fouling properties of this membrane design. Clearly, owing to its excellent operational stability and anti-fouling characteristics, the O-PDA/PEI membrane exhibits great potential for applications in dye sieving and salt separation. Full article

Drilling fluids are vital in oil and gas well operations, ensuring borehole stability, cutting removal, and pressure control. However, fluid loss into formations during drilling can compromise formation integrity, alter permeability, and risk groundwater contamination. Water-based drilling fluids (WBDFs) are favored for their environmental and cost-effective benefits but often require additives to address filtration and rheological limitations. This study explored the feasibility of using vegetable waste, including pumpkin peel (PP), courgette peel (CP), and butternut squash peel (BSP) in fine (75 μm) and very fine (10 μm) particle sizes as biodegradable WBDF additives. Waste vegetable peels were processed using ball milling and characterized via FTIR, TGA, and EDX. WBDFs, prepared per API SPEC 13A with 3 wt% of added additives, were tested for rheological and filtration properties. Results highlighted that very fine pumpkin peel powder (PP_10) was the most effective additive, reducing fluid loss and filter cake thickness by 43.5% and 50%, respectively. PP_10 WBDF maintained mud density, achieved a pH of 10.52 (preventing corrosion), and enhanced rheological properties, including a 50% rise in plastic viscosity and a 44.2% increase in gel strength. These findings demonstrate the remarkable potential of biodegradable vegetable peels as sustainable WBDF additives. Full article

Microplastics (MPs) are currently a serious environmental problem, primarily due to their persistence in the environment, low concentration, and difficulty in detection and disposal. MPs have also been detected in humans and have been shown to be harmful. Although there are methodologies for their recovery or elimination in most water treatment plants, a significant portion still bypasses these elimination systems. It is this percentage that we must try to eliminate. In addition to finding new methodologies for the treatment of MPs, it is important to find new materials adapted to this process. In this context, metal–organic frameworks (MOFs) are high-versatility compounds that can be synthesized using different techniques to obtain materials with different properties, such as porosity, morphology, conductivity, etc. These materials can adsorb MPs in different ways, such as electrostatic interaction, bond formation, etc., or they can be obtained by containing metals that catalyze reactions for the formation of highly reactive species that can oxidize the MPs. This review examines how MOF materials have gained attention for the adsorption-based recovery and removal of MPs and discusses the problems associated with these materials and possible solutions. Full article

An ultrafiltration (UF) installation was used to separate the actual wastewater from a car wash. Following these studies, the plant was washed several times; however, severe membrane fouling was observed during the filtration of sterile deionised (DI) water. As a result, the permeate flux decreased by more than 50% after 5 h of the UF process. The source of the fouling was the release of deposits, particularly bacteria, from the surfaces of plant elements such as pipes and pumps. The paper presents the effectiveness of biofilm removal from the surface of the equipment during a cyclically repeated washing process. Chemical washing was carried out using acid solutions and alkaline cleaning solutions containing NaOH (pH = 11.5–12). After installation cleaning, the filtration tests were carried out using DI water as a feed. It was determined how biofouling, which develops under these conditions, reduces permeate flux. Despite 3 h of installation washing, there was a 50% reduction in flux after 10 h of UF. Repeating the installation wash (4 h) resulted in a similar decrease in flux after 4 days of UF. Stabilisation of the flux at a level of 500 LMH was achieved after an additional 5 h of washing, including application of hot (323–333 K) alkaline cleaning solutions. The number of bacteria in the biofilm collected from the surface of the membranes, the pump inlet and the surface of the polyvinyl chloride (PVC) hoses forming the pipeline was also investigated. Despite repeated chemical cleaning, the number of bacteria on the pump and hose surfaces was 50–100 CFU/cm². Studies were carried out to determine which bacterial species survived the chemical cleaning of the installation. Gram-positive and Gram-negative bacteria were determined, and taxonomic characteristics of the isolated bacteria were identified. Full article

A novel protease was isolated from the fruiting bodies of the straw mushroom Volvariella volvacea. The protease was purified 13.48-fold using a series of techniques, including ammonium sulfate precipitation, ultrafiltration, diethylaminoethyl fast-flow (DEAE FF) ion-exchange chromatography, and Superdex 75 gel filtration chromatography, resulting in a specific enzyme activity of 286.82 U/mg toward casein as a substrate. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that the purified protease had a molecular weight of 24 kDa. The enzyme exhibited optimal activity at pH 7 and 50 °C, showing sensitivity to alkaline conditions and instability at elevated temperatures. The presence of Ca²⁺ significantly enhanced enzyme activity, whereas Ni²⁺ and Cu²⁺ exerted strong inhibitory effects, with other metal ions showing weak inhibition. β-mercaptoethanol, Tween-80, and Triton X-100 had more pronounced inhibitory effects, whereas PMSF, EDTA, and CTAB had weaker inhibitory effects. The Michaelis constant (Km) and maximum velocity (Vm) of the protease were determined to be 1.34 g/L and 3.45 μg/(mL·min), respectively. The protease exhibited a greater degree of enzymatic degradation of soybean-isolate protein (7.58%) compared to trypsin (5.24%), with the enzyme product containing a high percentage of medicinal amino acids (73.54%), particularly phenylalanine (Phe) and arginine (Arg), suggesting their presence at the enzyme’s active site. These findings suggest that the protease from V. volvacea holds promising potential for applications in the food industry, particularly in protein hydrolysate production and flavor enhancement. Full article

Lentils represent a promising alternative for beer production, potentially offering unique benefits and challenges. This study investigates the physicochemical properties of brewer’s wort derived from both barley and lentil grains. Specifically, it compares worts produced from raw and malted lentils, with and without the addition of amylase and protease enzymes. Key parameters such as filtration and saccharification times, pH, extract content, color, turbidity, polyphenol content, free amino nitrogen (FAN), nitrogen content, and metal ion and sugar composition were meticulously measured. Results indicate that both raw and malted lentils can be utilized to produce brewer’s wort, with the malting process enhancing extract levels. Notably, the addition of amylolytic enzymes resulted in the highest extract levels for both lentil types. Lentil-based worts exhibited significantly higher FAN levels and lower turbidity compared to barley malt worts. Despite barley malt’s established advantages in saccharification efficiency, filtration, and extract yield, lentils offer distinct benefits such as elevated FAN levels and unique color profiles. Enzyme treatments play a crucial role in optimizing lentil-based wort production, highlighting the potential for lentils in brewing applications. Full article

Background: Differences in serum creatinine (SCr) between the Jaffe and enzymatic methods affect the detection and staging of chronic kidney disease in kidney transplant recipients (KTRs). However, there are very limited data on the extent to which the detection of acute kidney injury (AKI) is affected, what impact immunosuppression can have and whether a KTR-specific estimated glomerular filtration rate (eGFR) formula is beneficial. Methods: A total of 12,081 parallel Jaffe/enzymatic SCr (eSCr) measurements of adult outpatient KTRs (61% male, median age 53 years) in the same serum sample at the University Hospital Essen (Germany) between January 2020 and October 2023 were evaluated. AKI and CKD were defined according to current KDIGO guidelines. The GFR was estimated using CKD-EPI and KTR-specific formulas. Results: In about 1% of all measurements and 5% of the KTR patients, the SCr difference between the two methods was ≥ 0.3 mg/dl. A total of 81% of these patients were male; the median age was 52 years. High levels of immunosuppression, including when Belatacept was used, did not seem to have a clinically relevant impact on the difference between Jaffe and eSCr. The KTR-specific eGFR formula generally showed a greater agreement between Jaffe and eSCr than the CKD-EPI eGFR formula, but they showed differences in the classification of CKD stages, especially in less severe stages. Conclusions: Clinically relevant SCr differences between Jaffe and SCr are rare and depend on the type of immunosuppression. A KTR-specific eGFR formula could be beneficial in some cases, but there are limitations in less severe CKD stages. Full article

This paper presents a method of sound source separation in live audio signals, based on sound intensity analysis. Sound pressure signals recorded with an acoustic vector sensor are analyzed, and the spectral distribution of sound intensity in two dimensions is calculated. Spectral components of the analyzed signal are selected based on the calculated source direction, which leads to a spatial filtration of the sound. The experiments were performed with test signals convolved with impulse responses of a real sensor, recorded for a varying sound source position. The experiments evaluated the proposed method’s ability to separate sound sources, depending on their position, spectral content, and signal-to-noise ratio, especially when multiple sources are active at the same time. The obtained results are presented and discussed. The proposed algorithm provided signal-to-distortion ratio (SDR) values 10–12 dB, and Short-Time Objective Intelligibility Measure (STOI) values in the range 0.86–0.94, an increase by 0.15–0.30 compared with the unprocessed speech signal. The proposed method is intended for applications in automated speech recognition systems, speaker diarization, and separation in the concurrent speech scenarios, using a small acoustic sensor. Full article

Water pollution is a critical environmental issue in modern society, and adsorption is recognized as a straightforward and efficient water purification technique. In this study, three new viologen-based ionic porous organic polymers were designed and successfully synthesized via a simple approach, and their adsorption properties for water pollutants were evaluated. The cationic nature of these polymers, coupled with their large conjugated π-electron system, physicochemical stability, and aromatic backbone, contributes to their high adsorption capacity and rapid adsorption efficiency for anionic contaminants in water such as Methyl Orange, Congo Red, and Cr (VI). The polymers exhibited maximum adsorption capacities of 1617 mg/g for MO, 3734 mg/g for CR, and 530.22 mg/g for Cr (VI), surpassing most previously reported adsorbents. Furthermore, the polymers maintained a high removal rate even in the presence of competing anions. Effective separation of anionic dyes from mixed solutions could be achieved through simple filtration. These characteristics make them promising candidates for water purification applications. Full article