AbstractUrea is a major issue in human wastewater because it may be easily broken down by the urease enzyme produced by bacteria, leading to ammonia production. Due to its ability to increase soil pH and eutrophicate streams, ammonia-containing effluent emissions pose environmental and health risks. This study aimed to evaluate the effectiveness of various treatment approaches in reducing urea concentrations by comparing the removal rates of conducting electrocoagulation (EC), EC followed by chemical coagulation (EC-CC), and CC followed by electrocoagulation (EC-CC). Numerous electrocoagulation parameters have been investigated, including current density, electrode gap distance, electrolyte type, concentration, and electrolysis duration. The electrode morphology was examined using a scanning electron microscope, while the produced sludge was analyzed using Fourier transform infrared spectroscopy. Three kinds of aluminum coagulants—potash alum, aluminum sulfate, and aluminum chloride—were used in the chemical coagulation, while the electrocoagulation was optimized at 30 A/m2. The results of this investigation suggest that the application of EC-CC, regardless of the type of coagulant used in both synthetic and real effluent, could marginally improve the efficacy of urea removal. Conversely, CC-EC exhibits an adverse effect on the efficiency of urea removal in both synthetic and real wastewater. The application of CC-EC demonstrated a significant improvement in the effectiveness of COD removal from actual wastewater, according to experimental results. The study emphasized the effectiveness and economic advantages of electrocoagulation over EC-CC and CC-EC techniques, used to remove urea from both real and synthetic wastewater.

AbstractThis paper contributes to the expanding knowledge base on nanomaterial-enhanced cementitious composites, offering valuable insights for developing high-performance, sustainable concrete solutions. The study assessed the effects of three different types of nanomaterials—nano clay (NC), nano silica (NS), and nano cellulose (NCel)—on the compressive strength of high-early-strength concrete (HESC) through both experimental studies and a 23 factorial design. Incorporating nanomaterials into the HESC matrix led to a decrease in workability, with NCel demonstrating the least impact on this property across all studied replacement percentages. All HESC mixes containing nanomaterials exhibited higher compressive strength than the control mix (M mix) across all ages. The optimal percentages for compressive strength enhancement were 4.5% NC (33.43% increase at 3 days, 22.29% at 7 days, and 12.15% at 28 days), 4.5% NS (20.12%, 11.14%, and 4.89% respectively), and 0.0375% NCel (34.91%, 25.76%, and 13.46% respectively). The highest compressive strength was observed in the hybrid mix containing 4.5% NC and 0.0375% NCel, yielding strength enhancements of 35.7%, 26%, and 12.75% compared to the M mix. Statistical analysis indicated that nano cellulose had the most significant contribution to enhancing compressive strength, followed by nano clay. The mathematical models derived from the statistical analyses provide a reliable means of predicting the compressive strength of HESC at 3, 7, and 28 days based on nanomaterial content. Contour plots illustrated the optimization of compressive strength across different nanomaterial contents at each age. In summary, the findings underscore the potential of waste-derived nanomaterials to enhance the performance of HESC, paving the way for innovative waste utilization strategies in construction. The study emphasizes the importance of reducing curing times, improving structural durability, and minimizing the environmental impact associated with concrete production.

AbstractGeophysical techniques have become increasingly crucial for characterizing landfills, offering noninvasive methods for subsurface exploration and contamination assessment. In this study, an integrated geophysical approach—utilizing magnetic, electrical resistivity tomography (ERT), and transient electromagnetic (TEM) surveys—was employed to characterize the Weidenpesch landfill in Cologne, Germany and assess potential groundwater contamination. The results from these methods were consistent, effectively delineating the landfill boundaries and identifying possible contamination. The waste body was distinguished by its relatively low resistivity values with an average value of 1–10 Ω·m in the western and central parts of the landfill and 20–50 Ω·m at its eastern part in contrast with the surrounding high-resistivity gravelly sand layer (several hundreds of Ω·m), and a depth of up to 15 m. The variability in conductivity and magnetic susceptibility across different landfill sections indicated the heterogeneity of buried materials. Additionally, the ERT and TEM data indicate low resistivity values (below 5 Ω·m) at depths of 20–25 m. A correlation with the borehole data suggests that this may represent a contaminated coal/clay layer. Furthermore, repeated TEM measurements revealed significant variation in subsurface conductivity over time, highlighting the need for continuous monitoring. This study demonstrates the effectiveness of an integrated geophysical approach for providing a comprehensive understanding of subsurface landfill conditions, which is essential for informed environmental management and remediation.

AbstractThe disposal of sharp waste generated at home by diabetic patients poses a major public health problem. This study evaluated an educational program designed to improve patients’ knowledge and practices around sharps disposal. A non-equivalent quasi-experimental study was performed at a main diabetic center in Egypt on 100 participants divided into intervention and non-intervention groups. The effect of the interventional program was tested by the evaluation of the improvement in participants’ knowledge and practice after two and four months of the program. Initially, there were no differences in knowledge or practice scores between the groups. After the implementation of the program, there was a noticeable difference in subjects’ knowledge levels and scores between the two groups, with the intervention group significantly outperforming the non-intervention group (p < 0.001). There was a significant improvement in overall practice scores in the intervention group across post-intervention visits, and they registered a score of 14/16, which matches a good practice level, while in the non-intervention group, the score remained unchanged at 4.4/16, which corresponds to a poor practice level (p < 0.001). These findings suggest that educational programs can effectively increase diabetic patients’ knowledge and improve their sharps waste disposal practices.Clinical trial registration number: PACTR202310841894237. Date: 05 October 2023, “retrospectively registered”.

AbstractOne of the biggest challenges in food packaging is the creation of sustainable and eco-friendly packaging materials to shield foods from ultraviolet (UV) photochemical damage and to preserve the distinctive physical, chemical, and biological characteristics of foods throughout the supply chain. Accordingly, this study focuses on enhancing the UV shielding properties and biological activity of carboxylmethyl cellulose sodium (CMC) through modifications using zinc oxide (ZnO), copper oxide (CuO), and graphene oxide (GO) using the solution casting technique. The hybrid nanocomposites were characterized by fourier-transform infrared (FTIR) spectrophotometer, ultraviolet-visible (UV-Vis) spectrophotometer, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and x-ray diffraction (XRD). Significant interactions between CMC and the metal oxide/GO nanocomposites were revealed by FTIR analysis, which reflects the formation of hydrogen bonding between CMC and the nanocomposites. XRD confirmed the functionalization of CMC with ZnO/GO and CuO/GO nanocomposites. Additionally, the CMC film showed a decrease in the optical bandgap from 5.53 to 3.43 eV with improved UV shielding capacity. Moreover, the composite films had excellent refractive index and optical conductivity values of 1.97 and 1.56 × 1010 Ω cm− 1, respectively. SEM and EDX analysis confirmed the formation of ZnO/GO and CuO/GO within the CMC matrix. Thus, dedicates that the CMC nanocomposites have promising applications in packaging materials. These results were confirmed by the quantum mechanical calculations utilizing density functional theory (DFT). Total dipole moment (TDM), frontier molecular orbitals (FMOs), chemical reactivity descriptors, and molecular electrostatic potential (MESP) maps were all studied using the B3LYP/LanL2DZ model. The TDM and FMO investigations revealed that the CMC/CuO/GO model has the highest TDM (84.031 Debye) and the smallest band gap energy (0.118 eV). Moreover, CMC’s reactivity increased after CuO/GO nanocomposites integration, as demonstrated by MESP mapping. Finally, the antibacterial activity of pure CMC, CMC/ZnO/GO, and CMC/CuO/GO nanocomposite films was evaluated against Staphylococcus aureus and Escherichia coli. The zones of inhibition data showed that both CMC/ZnO/GO and CMC/CuO/GO exhibited higher antibacterial activity than CMC alone, particularly against S. aureus. The inhibition zones for CMC/ZnO/GO and CMC/CuO/GO against S. aureus were 16 mm and 14 mm, respectively, suggesting enhanced susceptibility of S. aureus compared to E. coli. These results highlight the significant potential of ZnO and CuO NPs in improving the antimicrobial efficacy of CMC nanocomposites.

AbstractMany animals alternate between different media, such as air and water, thanks to specific adaptations. Among birds, penguins (Sphenisciformes) have the most extreme morphological, physiological, and behavioural adaptations to their amphibious lifestyle. Their auditory perception of sound, potentially matching different impedances in air and under water, is largely unknown particularly in terms of whether their underwater adaptations may have affected their in-air hearing capacity. In this context, we investigated the hearing ability of four captive Humboldt penguins (Spheniscus humboldti) in air using psychophysical hearing tests. The 50% hit rate was found to be below 76 dB rms re 20 µPa between 0.250 kHz and 10 kHz, with most sensitive hearing at 2 kHz (mean threshold of 15.3 dB rms re 20 µPa). The four penguins showed large inter-individual variation in sensitivity at a given frequency but within a common audiogram shape. Despite the variability, penguins detected 0.250 kHz at comparably low sound levels (mean = 36.8 dB rms re 20 µPa) after a rapid decline of sensitivity at 0.500 kHz (mean = 64.1 dB rms re 20 µPa). This finding was unexpected, and it is therefore difficult to interpret whether it is an artefact of the methods or a biologically relevant finding. An extensive discussion is presented and suggests that this finding may be biologically relevant but would need further investigation to reveal the underlying mechanisms.

AbstractIn pathological examinations, gastric ulcers are often detected in South American camelids. The aetiology cannot be clarified in every case. However, tumour-related gastric ulcers are observed repeatedly. This study reports clinical, laboratory and pathological findings in six alpacas, three each with adenocarcinoma- and squamous cell carcinoma-associated gastric ulcers. Clinically they were presented with general symptoms like emaciation, anorexia and recumbency. Laboratory findings of these animals were non-specific. All animals were at least nine years old. The adenocarcinomas as well as the squamous cell carcinomas were metastasised in various organs, especially in the lymph nodes. Two adenocarcinoma-associated gastric ulcers were perforated. In summary, squamous cell carcinomas and adenocarcinomas can lead to ulcerative lesions in the gastrointestinal tract. Although neoplasms are rare overall, they should be considered as a possible differential diagnosis in the case of non-specific symptoms. In particular, older animals seem to be affected more frequently.

AbstractObjectives: C-Reactive Protein (CRP) values are partly determined by variation at the CRP gene locus, but also influenced by socioeconomic position (SEP) and related lifestyle factors. As gene-by-SEP interactions have been suggested for traits associated with CRP and SEP (e.g., BMI, coronary artery disease), the aim of this study was to investigate the strength of a possible interaction between a CRP gene common variant (rs4287174) and SEP in their joint influence on CRP levels in a population-based study sample. Methods: Single nucleotide polymorphism rs4287174 was genotyped in 4065 participants (aged 45–75 years) of the Heinz Nixdorf Recall study, a population-based prospective cohort. SEP indicators (education and income), risk factors (i.e., body mass index (BMI), total cholesterol, diabetes mellitus, coronary artery calcification, current smoking, hypertension, diet, no exercise) and blood serum CRP (mg/dl) were assessed at study baseline. Interaction analysis was based on linear regression and on stratified analyses (genetic effect stratified by SEP and vice versa) adjusted for age and sex using loge(CRP + 1) as dependent variable. Results: Low SEP and rs4287174 T allele were both associated with higher CRP values. The strongest genetic effect was observed in the lowest educational group (≤ 10 years of education) with an exp(β) indicating 1.058-fold (95%-CI: 1.018; 1.100) average CRP values per additional T allele, while in the highest educational group (≥ 18 years) the association was considerably less strong (exp(β): 1.005 (95%-CI: 0.975; 1.037)). After including rs4287174-by-education interaction terms in the regression analysis, interaction was indicated suggesting stronger genetic effects on CRP in low SEP groups (exp(βinteraction): 1.056 (95%-CI: 1.005; 1.108); p = 0.029). The observed interaction did not seem to be substantially mediated by the risk factors included in the analysis. No indication for rs4287174-by-income interaction was observed. Conclusion: Results imply that genetic effects of the CRP locus are modified by education as an indicator of life course SEP.