Breakdown of Boltzmann-type models for the alignment of self-propelled rods.

Studies in the collective motility of organisms use a range of analytical approaches to formulate continuous kinetic models of collective dynamics from rules or equations describing agent interactions. However, the derivation of these kinetic models often relies on Boltzmann's "molecular chaos" hypothesis, which assumes that correlations between individuals are short-lived. While this assumption is often the simplest way to derive tractable models, it is often not valid in practice due to the high levels of cooperation and self-organization present in biological systems. In this work, we illustrated this point by considering a general Boltzmann-type kinetic model for the alignment of self-propelled rods where rod reorientation occurs upon binary collisions. We examine the accuracy of the kinetic model by comparing numerical solutions of the continuous equations to an agent-based model that implements the underlying rules governing microscopic alignment. Even for the simplest case considered, our comparison demonstrates that the kinetic model fails to replicate the discrete dynamics due to the formation of rod clusters that violate statistical independence. Additionally, we show that introducing noise to limit cluster formation helps improve the agreement between the analytical model and agent simulations but does not restore the agreement completely. These results highlight the need to both develop and disseminate improved moment-closure methods for modeling biological and active matter systems.

Investigation of the link between first-order kinetic models of the in vitro digestion of native starches and the accompanying changes in their crystallinity and structure.

Starch is the main source of dietary energy for humans. In order to understand the mechanisms governing native starch in vitro digestion, digestion data for six starches [wheat, maize, (waxy) maize, rice, potato and pea] of different botanical sources were fitted with the most common first-order kinetic models, i.e. the single, sequential, parallel and combined models. Parallel and combined models provided the most accurate fits and showed that all starches studied except potato starch followed a biphasic in vitro digestion pattern. The biological relevance of the kinetic parameters was explored by determining changes in crystallinity and molecular structure of the undigested starch residues during in vitro digestion. While the crystallinity of the undigested potato starch residues did not change substantially, a respectively small and large decrease in their amylose content and chain length during in vitro digestion was observed, indicating that amylose was digested slightly preferentially over amylopectin in native starch. However, the molecular structure of the starch residues changed too slowly and/or only to an insufficient extent to relate it to the kinetic parameters of the digested fractions predicted by the models. Such parameters thus need to be interpreted with caution, as their biological relevance still needs to be proven.

Biocomposite Material Based on Lactococcus lactis sp. Immobilized in Natural Polymer Matrix for Pharmaceutical Removal from Aqueous Media.

Ecosystems are negatively impacted by pharmaceutical-contaminated water in different ways. In this work, a new biosorbent obtained by immobilizing Lactococcus lactis in a calcium alginate matrix was developed for the removal of pharmaceuticals from aqueous solutions. Ethacridine lactate (EL) was selected as the target drug. Lactococcus Lactis biomass was chosen for the biosorbent synthesis for two reasons: (i) the microbial biomass used in the food industry allows the development of a low-cost biosorbent from available and renewable materials, and (ii) there is no literature mentioning the use of Lactococcus Lactis biomass immobilized in natural polymers as a biosorbent for the removal of pharmaceuticals. The characterization of the synthesized biosorbent named 5% LLA was performed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. Additionally, particle size and the point of zero charge were established. Batch biosorption investigations showed that using 5% LLA at an initial pH of 3.0 and a biosorbent dose of 2 g/L resulted in up to 80% EL removal efficiency for all EL initial concentrations (20-60 mg/L). Four equilibrium isotherms, given in the order of Redlich-Peterson > Freundlich > Hill > Temkin, are particularly relevant for describing the experimental data for EL biosorption on the 5% LLA biosorbent using correlation coefficient values. Kinetic parameters were determined using kinetic models such as pseudo-first-order, pseudo-second-order, Elovich, Avrami and Weber-Morris. The pseudo-second-order kinetics model provides the greatest fit among the evaluated equations, with correlation coefficients greater than 0.99. According to the study's findings, the developed biocomposite is a potentially useful material for the removal of pharmaceuticals from aqueous matrices.

Efficacy, kinetics, inactivation mechanism and application of cold plasma in inactivating Alicyclobacillus acidoterrestris spores.

As spores of Alicyclobacillus acidoterrestris can survive traditional pasteurization, this organism has been suggested as a target bacterium in the fruit juice industry. This study aimed to investigate the inactivation effect of cold plasma on A. acidoterrestris spores and the mechanism behind the inactivation. The inactivation effect was detected by the plate count method and described by kinetic models. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), the detection of dipicolinic acid (DPA) release and heat resistance detection, the detection and scavenging experiment of reactive species, and cryo-scanning electron microscopy were used to explore the mechanism of cold plasma inactivation of A. acidoterrestris. The results showed that cold plasma can effectively inactivate A. acidoterrestris spores in saline with a 3.0 ± 0.3 and 4.4 ± 0.8 log reduction in CFU/mL, for 9 and 18 min, respectively. The higher the voltage and the longer the treatment time, the stronger the overall inactivation effect. However, a lower gas flow rate may increase the probability of spore contact with reactive species, resulting in better inactivation results. The biphasic model fits the survival curves better than the Weibull model. SEM and TEM revealed that cold plasma treatment can cause varying degrees of damage to the morphology and structure of A. acidoterrestris spores, with at least 50 % sustaining severe morphological and structural damage. The DPA release and heat resistance detection showed that A. acidoterrestris spores did not germinate but died directly during the cold plasma treatment. 1O2 plays the most important role in the inactivation, while O3, H2O2 and NO3- may also be responsible for inactivation. Cold plasma treatment for 1 min reduced A. acidoterrestris spores in apple juice by 0.4 ± 0.0 log, comparable to a 12-min heat treatment at 95 °C. However, as the treatment time increased, the survival curve exhibited a significant tailing phenomenon, which was most likely caused by the various compounds in apple juice that can react with reactive species and exert a physical shielding effect on spores. Higher input power and higher gas flow rate resulted in more complete inactivation of A. acidoterrestris spores in apple juice. What's more, the high inactivation efficiency in saline indicates the cold plasma device provides a promising alternative for controlling A. acidoterrestris spores during apple washing. Overall, our study provides adequate data support and a theoretical basis for using cold plasma to inactivate A. acidoterrestris spores in the food industry.

Alginate/hyaluronic acid/gelatin ternary blended films as pH-sensitive drug carriers: In vitro ampicillin release and kinetic studies.

Researchers continuously focused on the fabrication of innovative drug delivery systems to prevent microbial infections while minimizing systemic side effects. Among these, pH-sensitive antibiotic release systems based on bio-based materials have gained great attention due to their ability to precisely modulate drug kinetics and enhance therapeutic efficacy. Herein, pH-sensitive alginate/hyaluronic acid/gelatin ternary blended films were fabricated for the controlled release of ampicillin. Swelling capacity, hydrolytic degradation profile, pH reversibility and in vitro ampicillin release behavior of produced films were investigated in both simulated gastric (pH 1.2) and intestinal (pH 7.4) environments. The cumulative release amount of ampicillin at pH 1.2 (61.0 ± 1.07 mg drug/g polymer) was greater than that of at pH 7.4 (43.0 ± 1.05 mg drug/g polymer) proved that release behavior of ampicillin for produced films is pH-dependent. Based on the fitted release data, best fit was found as the first-order kinetic model with the highest R2 values of 0.966 and 0.962 for both pH conditions. According to Korsmeyer-Peppas model, drug release mechanism is also controlled by case II-transport. Furthermore, produced films demonstrated excellent cytocompatibility. All results revealed that obtained films could be a promising drug carrier to traditional targeting systems for site-specific, pH-sensitive ampicillin delivery in both gastric and intestine.

Preparation and potential of chitosan-based/Al2O3 green hydrogel composites for the removal of methyl red dye from simulated solution.

Different dyes are discharged into water streams, causing significant pollution to the entire ecosystem. The present work deals with the removal of acid red 2 dye (methyl red-as an anionic dye) by green sorbents based on chitosan derivatization. In this regard, two classes of chitosan derivatives-a total of six-were prepared by gamma irradiation at 30 kGy. The first group (group A) constitutes a crosslinked chitosan/polyacrylamide/aluminum oxide with different feed ratios, while the second group, identified as group B, is composed of crosslinked carboxymethyl chitosan/polyacrylamide/aluminum oxide with different ratios. Glycerol was added to soften the resultant hydrogels. The products were characterized by different tools, including FTIR for confirming the chemical modification, TGA for investigating their thermal properties, and XRD for verifying their crystalline structure. The morphology of the prepared derivatives was studied through SEM, while their topography before and after dye adsorption was monitored via the AFM. The removal efficiencies of the prepared sorbents were verified at different operation conditions, such as pH, temperature, adsorbent dose, initial concentration of dye solutions, and contact time. The data revealed that the optimum conditions for maximum dye uptake were as follows: pH 4, contact time 120 min, 0.1-g sorbent dose, and 50-ppm dye concentration. Additionally, the prepared sorbents demonstrated potent adsorption capacity and removal efficiency. It was found that the elements of the second group displayed higher performance than their counterparts. The data showed also that the adsorption process best fits with the Freundlich model and obeyed pseudo-first-order kinetic isotherm. In addition, the synthesized composites showed observable antibacterial potency toward E. coli as a Gram-negative bacterium and S. aureus as a Gram-positive bacterium.

The Influence of Kinetic Models and Attenuation Correction on Cadmium-Zinc-Telluride Single-Photon Emission Computed Tomography (CZT SPECT)-Derived Myocardial Blood Flow and Reserve: Correlation with Invasive Angiography Data.

(1) Background: The objective of this study was to determine the optimal post-processing model for dynamic cadmium-zinc-telluride single-photon emission computed tomography (CZT-SPECT). (2) Methods: A total of 235 patients who underwent diagnostic invasive coronary angiography within three months of the SPECT and those who had coronary computed tomography angiography (CCTA) before SPECT (within 3 months) were enrolled in this study. Each SPECT study was processed to obtain global and regional stress myocardial blood flow (sMBF), rest-MBF (rMBF), myocardial flow reserve (MFR) and flow difference (FD) estimates obtained with 1-tissue-compartment (1TCM) and net retention (NR) modes, both with and without attenuation correction. (3) Results: The use of AC led to significantly higher sMBF, rMBF and DF values obtained by 1TCM compared those values derived by 1TCM with NAC; the lowest values of stress MBF and rest MBF were obtained by 1TCM_NAC. The resting flow, MFR and DF were significantly (p < 0.005) higher in the AC model than in NAC. All quantitative variables were significantly (p < 0.05) higher in NR_NAC than in the 1TC_NAC model. Finally, sMBF, rMBF and FD showed significantly (p < 0.05) higher values by using 1TMC_AC compared to NR_AC. (4) Conclusions: We suggested that 1-compartment and net retention models correctly reflect coronary microcirculation and can be used for clinical practice for evaluating quantitative myocardial perfusion by dynamic SPECT. Attenuation correction is an important step in post-processing dynamic SPECT data, which increases the consistency and diagnostic accuracy of models.

Bayesian Regression Facilitates Quantitative Modeling of Cell Metabolism.

This paper presents Maud, a command-line application that implements Bayesian statistical inference for kinetic models of biochemical metabolic reaction networks. Maud takes into account quantitative information from omics experiments and background knowledge as well as structural information about kinetic mechanisms, regulatory interactions, and enzyme knockouts. Our paper reviews the existing options in this area, presents a case study illustrating how Maud can be used to analyze a metabolic network, and explains the biological, statistical, and computational design decisions underpinning Maud.

Kinetics-based inference of environment-dependent microbial interactions and their dynamic variation.

Microbial communities in nature are dynamically evolving as member species change their interactions subject to environmental variations. Accounting for such context-dependent dynamic variations in interspecies interactions is critical for predictive ecological modeling. In the absence of generalizable theoretical foundations, we lack a fundamental understanding of how microbial interactions are driven by environmental factors, significantly limiting our capability to predict and engineer community dynamics and function. To address this issue, we propose a novel theoretical framework that allows us to represent interspecies interactions as an explicit function of environmental variables (such as substrate concentrations) by combining growth kinetics and a generalized Lotka-Volterra model. A synergistic integration of these two complementary models leads to the prediction of alterations in interspecies interactions as the outcome of dynamic balances between positive and negative influences of microbial species in mixed relationships. The effectiveness of our method was experimentally demonstrated using a synthetic consortium of two Escherichia coli mutants that are metabolically dependent (due to an inability to synthesize essential amino acids) but competitively grow on a shared substrate. The analysis of the E. coli binary consortium using our model not only showed how interactions between the two amino acid auxotrophic mutants are controlled by the dynamic shifts in limiting substrates but also enabled quantifying previously uncharacterizable complex aspects of microbial interactions, such as asymmetry in interactions. Our approach can be extended to other ecological systems to model their environment-dependent interspecies interactions from growth kinetics.IMPORTANCEModeling environment-controlled interspecies interactions through separate identification of positive and negative influences of microbes in mixed relationships is a new capability that can significantly improve our ability to understand, predict, and engineer the complex dynamics of microbial communities. Moreover, the prediction of microbial interactions as a function of environmental variables can serve as valuable benchmark data to validate modeling and network inference tools in microbial ecology, the development of which has often been impeded due to the lack of ground truth information on interactions. While demonstrated against microbial data, the theory developed in this work is readily applicable to general community ecology to predict interactions among macroorganisms, such as plants and animals, as well as microorganisms.

An overview on the key advantages and limitations of batch and dynamic modes of biosorption of metal ions.

Water purification using adsorption is a crucial process for maintaining human life and preserving the environment. Batch and dynamic adsorption modes are two types of water purification processes that are commonly used in various countries due to their simplicity and feasibility on an industrial scale. However, it is important to understand the advantages and limitations of these two adsorption modes in industrial applications. Also, the possibility of using batch mode in industrial scale was scrutinized, along with the necessity of using dynamic mode in such applications. In addition, the reasons for the necessity of performing batch adsorption studies before starting the treatment on an industrial scale were mentioned and discussed. In fact, this review article attempts to throw light on these subjects by comparing the biosorption efficiency of some metals on utilized biosorbents, using both batch and fixed-bed (column) adsorption modes. The comparison is based on the effectiveness of the two processes and the mechanisms involved in the treatment. Parameters such as biosorption capacity, percentage removal, and isotherm models for both batch and column (fixed bed) studies are compared. The article also explains thermodynamic and kinetic models for batch adsorption and discusses breakthrough evaluations in adsorptive column systems. The review highlights the benefits of using convenient batch-wise biosorption in lab-scale studies and the key advantages of column biosorption in industrial applications.

Comparative Analysis of Hydrogel Adsorption/Desorption with and without Surfactants.

In this particular study, a hydrogel known as SAP-1 was synthesized through the grafting of acrylic acid-co-acrylamide onto pullulan, resulting in the creation of Pul-g-Poly (acrylic acid-co-acrylamide). Additionally, a sponge hydrogel named SAP-2 was prepared by incorporating the surfactant sodium dodecyl benzene sulfonate (SDBS) into the hydrogel through free radical solution polymerization. To gain further insight into the composition and properties of the hydrogels, various techniques, such as Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H NMR), atomic absorption spectroscopy, and field emission scanning electron microscopy (FE-SEM), were employed. Conversely, the absorption kinetics and the equilibrium capacities of the prepared hydrogels were investigated and analyzed. The outcomes of the investigation indicated that each of the synthesized hydrogels exhibited considerable efficacy as adsorbents for cadmium (II), copper (II), and nickel (II) ions. In particular, SAP-2 gel displayed a remarkable cadmium (II) ion absorption ability, with a rate of 190.72 mg/g. Following closely, SAP-1 gel demonstrated the ability to absorb cadmium (II) ions at a rate of 146.9 mg/g and copper (II) ions at a rate of 154 mg/g. Notably, SAP-2 hydrogel demonstrated the ability to repeat the adsorption-desorption cycles three times for cadmium (II) ions, resulting in absorption capacities of 190.72 mg/g, 100.43 mg/g, and 19.64 mg/g for the first, second, and third cycles, respectively. Thus, based on the abovementioned results, it can be concluded that all the synthesized hydrogels possess promising potential as suitable candidates for the adsorption and desorption of cadmium (II), copper (II), and nickel (II) ions.

Modelling contagious viral dynamics: a kinetic approach based on mutual utility.

The temporal evolution of a contagious viral disease is modelled as the dynamic progression of different classes of population with individuals interacting pairwise. This interaction follows a binary mechanism typical of kinetic theory, wherein agents aim to improve their condition with respect to a mutual utility target. To this end, we introduce kinetic equations of Boltzmann-type to describe the time evolution of the probability distributions of the multi-agent system. The interactions between agents are defined using principles from price theory, specifically employing Cobb-Douglas utility functions for binary exchange and the Edgeworth box to depict the common exchange area where utility increases for both agents. Several numerical experiments presented in the paper highlight the significance of this mechanism in driving the phenomenon toward endemicity.

Hydrogels Based on Chitosan and Nanoparticles and Their Suitability for Dyes Adsorption from Aqueous Media: Assessment of the Last-Decade Progresses.

Water is one of the fundamental resources for the existence of humans and the environment. Throughout time, due to urbanization, expanding population, increased agricultural production, and intense industrialization, significant pollution with persistent contaminants has been noted, placing the water quality in danger. As a consequence, different procedures and various technologies have been tested and used in order to ensure that water sources are safe for use. The adsorption process is often considered for wastewater treatment due to its straightforward design, low investment cost, availability, avoidance of additional chemicals, lack of undesirable byproducts, and demonstrated significant efficacious potential for treating and eliminating organic contaminants. To accomplish its application, the need to develop innovative materials has become an essential goal. In this context, an overview of recent advances in hydrogels based on chitosan and nanocomposites and their application for the depollution of wastewater contaminated with dyes is reported herein. The present review focuses on (i) the challenges raised by the synthesis process and characterization of the different hydrogels; (ii) the discussion of the impact of the main parameters affecting the adsorption process; (iii) the understanding of the adsorption isotherms, kinetics, and thermodynamic behavior; and (iv) the examination of the possibility of recycling and reusing the hydrogels.

Impact of (nano ZnO/multi-wall CNTs) prepared by arc discharge method on the removal efficiency of stable iodine 127I and radioactive iodine 131I from water.

Radioactive iodine isotopes especially 131I are used for diagnosis and treatment of different types of cancer diseases. Due to the leak of radioactive iodine into the patient's urine in turn, the wastewater would be contaminated, so it is worth preparing a novel adsorption green material to remove the radioactive iodine from wastewater efficiently. The removal of 127I and 131I contaminants from aqueous solution is a problem of interest. Therefore, this work presents a new study for removing the stable iodine 127I- and radioactive iodine 131I from aqueous solutions by using the novel nano adsorbent (Nano ZnO/MWCNTs) which is synthesized by the arc discharge method. It is an economic method for treating contaminated water from undesired dissolved iodine isotopes. The optimal conditions for maximum removal are (5 mg/100 ml) as optimum dose with shacking (200 rpm) for contact time of (60 min), at (25 °C) in an acidic medium of (pH = 5). After the adsorption process, the solution is filtrated and the residual iodide (127I-) is measured at a maximum UV wavelength absorbance of 225 nm. The maximum adsorption capacity is (15.25 mg/g); therefore the prepared nano adsorbent (Nano ZnO/MWCNTs) is suitable for treating polluted water from low iodide concentrations. The adsorption mechanism of 127I- on to the surface of (Nano ZnO/MWCNTs) is multilayer physical adsorption according to Freundlich isotherm model and obeys the Pseudo-first order kinetic model. According to Temkin isotherm model the adsorption is exothermic. The removal efficiency of Nano ZnO/MWCNTs for stable iodine (127I-) from aqueous solutions has reached 97.23%, 89.75%, and 64.78% in case of initial concentrations; 0.1843 ppm, 0.5014 ppm and 1.0331 ppm, respectively. For the prepared radio iodine (131I-) solution of radioactivity (20 µCi), the dose of nano adsorbent was (10 mg/100 ml) and the contact time was (60 min) at (pH = 5) with shacking (200 rpm) at (25 °C). The filtration process was done by using a syringe filter of a pore size (450 nm) after 2 days to equilibrate. The removal efficiency reached (34.16%) after the first cycle of treatment and the percentage of residual radio iodine was (65.86%). The removal efficiency reached (94.76%) after five cycles of treatment and the percentage of residual radio iodine was (5.24%). This last percentage was less than (42.15%) which produces due to the natural decay during 10 days.

Deconvolution-Based Pharmacokinetic Analysis to Improve the Prediction of Pathological Information of Breast Cancer.

Pharmacokinetic (PK) parameters, revealing changes in the tumor microenvironment, are related to the pathological information of breast cancer. Tracer kinetic models (e.g., Tofts-Kety model) with a nonlinear least square solver are commonly used to estimate PK parameters. However, the method is sensitive to noise in images. To relieve the effects of noise, a deconvolution (DEC) method, which was validated on synthetic concentration-time series, was proposed to accurately calculate PK parameters from breast dynamic contrast-enhanced magnetic resonance imaging. A time-to-peak-based tumor partitioning method was used to divide the whole tumor into three tumor subregions with different kinetic patterns. Radiomic features were calculated from the tumor subregion and whole tumor-based PK parameter maps. The optimal features determined by the fivefold cross-validation method were used to build random forest classifiers to predict molecular subtypes, Ki-67, and tumor grade. The diagnostic performance evaluated by the area under the receiver operating characteristic curve (AUC) was compared between the subregion and whole tumor-based PK parameters. The results showed that the DEC method obtained more accurate PK parameters than the Tofts method. Moreover, the results showed that the subregion-based Ktrans (best AUCs = 0.8319, 0.7032, 0.7132, 0.7490, 0.8074, and 0.6950) achieved a better diagnostic performance than the whole tumor-based Ktrans (AUCs = 0.8222, 0.6970, 0.6511, 0.7109, 0.7620, and 0.5894) for molecular subtypes, Ki-67, and tumor grade. These findings indicate that DEC-based Ktrans in the subregion has the potential to accurately predict molecular subtypes, Ki-67, and tumor grade.

Ibuprofen-Loaded Silver Nanoparticle-Doped PVA Gels: Green Synthesis, In Vitro Cytotoxicity, and Antibacterial Analyses.

In contrast to conventional drug delivery systems, controlled drug release systems employ distinct methodologies. These systems facilitate the release of active substances in predetermined quantities and for specified durations. Polymer hydrogels have gained prominence in controlled drug delivery because of their unique swelling-shrinkage behavior and ability to regulate drug release. In this investigation, films with a hydrogel structure were crafted using polyvinyl alcohol, a biocompatible polymer, and silver nanoparticles. Following characterization, ibuprofen was loaded into the hydrogels to evaluate their drug release capacity. The particle sizes of silver nanoparticles synthesized using a green approach were determined. This study comprehensively examined the structural properties, morphological features, mechanical strength, and cumulative release patterns of the prepared films. In vitro cytotoxicity analysis was employed to assess the cell viability of drug-loaded hydrogel films, and their antibacterial effects were examined. The results indicated that hydrogel films containing 5% and 10% polyvinyl alcohol released 89% and 97% of the loaded drug, respectively, by day 14. The release kinetics fits the Korsmeyer-Peppas model. This study, which describes nanoparticle-enhanced polyvinyl alcohol hydrogel systems prepared through a cost-effective and environmentally friendly approach, is anticipated to contribute to the existing literature and serve as a foundational study for future research.

Electromagnetic fields effects on microbial growth in cocoa fermentation: A controlled experimental approach using established growth models.

Understanding the effects of electromagnetic fields is crucial in the fermentation of cocoa beans, since through precise control of fermentation conditions the sensory and nutritional properties of cocoa beans could be improved. This study aimed to evaluate the effect of oscillating magnetic fields (OMF) on the kinetic growth of the core microbial communities of the Collections Castro Naranjal (CCN 51) cocoa bean. The data was obtained by three different models: Gompertz, Baranyi, and Logistic. The cocoa beans were subjected to different OMF strengths ranging from 0 mT to 80 mT for 1 h using the Helmholtz coil electromagnetic device. The viable microbial populations of lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeast (Y) were quantified using the colony-forming unit (CFU) counting method. The logistic model appropriately described the growth of LAB and Y under magnetic field exposure. Whereas the Baranyi model was suitable for describing AAB growth. The microbial populations in cocoa beans exposed to magnetic fields showed lower (maximum specific growth rate (µmax), values than untreated controls, with AAB exhibiting the highest average growth rate value at 5 mT and Y having the lowest average maximum growth rate value at 80 mT. The lower maximum specific growth rates and longer lag phases when exposed to magnetic fields compared to controls demonstrate the influence of magnetic fields on microbial growth kinetics.

Enhanced photocatalytic degradation of polycyclic aromatic hydrocarbons (PAHs) Using NiO nanoparticles.

The oncogenic and genetic properties of anthracene, a member of the polycyclic aromatic hydrocarbons (PAHs) family, pose a significant health threat to humans. This study aims to investigate the photocatalytic decomposition of anthracene under various conditions, such as different concentrations of PAHs, varying amounts of NiO (nickel oxide) nanoparticles, and different pH levels under ultraviolet light and sunlight. The synthesized NiO nanoparticles showed surface plasma resonance at 230 and 360 nm, while XRD and SEM analysis confirmed the nanoparticles were cubic crystalline in structure with sizes ranging between 37 and 126 nm. NiO nanoparticles exhibited 79% degradation of pyrene at 2 µg/mL of anthracene within 60 min of treatment. NiO at 10 µg/mL concentration showed significant adsorption of 57%, while the adsorption method worked efficiently (72%) at 5 pH. Photocatalytic degradation was confirmed by isotherm and kinetic studies through monolayer adsorption and pseudo-first-order kinetics. Further, the absorption process was confirmed by performing GC-MS analysis of the NiO nanoparticles. On the other hand, NiO nanoparticles showed antimicrobial activity against Gram negative and Gram-positive bacteria. Therefore, the present work is one of its kind proving the dual application of NiO nanoparticles, which makes them suitable candidates for bioremediation by treating PAHs and killing pathogenic bacteria.

Utilization of aquatic biomass as biosorbent for sustainable production of high surface area, nano- microporous, for removing two dyes from wastewater.

The majority of environmental researchers are becoming increasingly concerned with the manufacture of inexpensive adsorbents for the detoxification of industrial effluents. To address one of the significant and well-known pollution issues with certain drains that act as hotspots and contribute to coastal pollution in Alexandria, this study aims to develop an economical, ecologically friendly sorbent. This study assessed the efficacy of a biomass-coated magnetic composite and a magnetic active adsorbent for the removal of two dyes from an industrially contaminated sewer using a wetland plant (Phragmites australis). Using magnetic biosorbent, the biosorption of Xylenol orange and Congo red ions from polluted drain discharge in Abu Qir Bay was evaluated in the current study. Using scanning electron microscopy imaging and Fourier transform infra-red analysis; the surface function and morphology of the nano-biosorbent were examined. At room temperature, the effects of initial dye concentration, pH, contact time, and nano-biosorbent concentration have all been investigated. The greatest percentages that nano-biosorbent can remove from Congo red and Xylenol orange are 97% and 47%, respectively. The removal of the initial Congo red concentration varied from 42 to 97%, while the removal of the initial Xylenol orange concentration varied from 30 to 47%. The adsorption capacity was shown to be strongly pH-dependent; capacity dose as pH value increased, with pH 10 being the ideal pH for Congo red and pH 6 being the ideal pH value for Xylenol orange. The adsorption capacity for Congo red varied between 0.96 and 3.36 and the adsorption capacity for Xylenol orange varied between 0.18 and 17.58. The removal capacity decreased from 3.36 to 0.96 mg/g when the biosorbent dosage was increased from 0.05 to 0.5 g/L for Congo red, in case of Xylenol orange, the removal capacity increased from 0.18 to 17.58 mg/g when the biosorbent dosage was increased from 0.05 to 0.5 g/L. The removal capacity of Congo red increases quickly with time and varied from 1.66 to 1.88 of contact time; while the removal capacity of Xylenol orange varied between 3.08 and 4.62 of contact time. For the dyes under study, kinetics and adsorption equilibrium were examined. Within 180 min, the equilibrium was attained because to the quick adsorption process. For Congo red and Xylenol orange, the highest adsorption capacities were 3.36 and 17.58 mg g-1, respectively. The equilibrium data were assessed using a number of isotherm models, including Langmuir, Freundlich, BET, and Tempkin, while the kinetic data were examined using a variety of kinetic models, including pseudo-first- and pseudo-second-order equations. The pseudo-second-order equation provides the greatest accuracy for the kinetic data and Langmuir model is the closest fit for the equilibrium data.

The performance of pharmaceutical wastewater treatment system of electrocoagulation assisted adsorption using perforated electrodes to reduce passivation.

The integrated electrocoagulation-assisted adsorption (ECA) system with a solar photovoltaic power supply has gained more attention as an effective approach for reduction chemical oxygen demand (COD) from pharmaceutical wastewater (PhWW). In this research, the ECA system was used for the treatment of PhWW. Several operating parameters were investigated, including electrode number, configuration, distance, operating time, current density, adsorption time, and temperature. A current density of 6.656 mA/cm2, six electrodes, a 20-min time, a 4 cm distance, an MP-P configuration, and a 45 °C temperature produced the maximum COD reductions, where the operating cost of conventional energy was 0.273 $/m3. The EC, adsorption, and combination of EC and adsorption processes achieved efficient COD reductions of 85.4, 69.1, and 95.5%, respectively. The pseudo-second-order kinetic model and the Freundlich isotherm fit the data of the endothermic adsorption process. Therefore, it was found that the combination processes were superior to the use of these processes in isolation to remove COD.