Search Results (278)

The extensive use of clothianidin pesticide poses significant risks to non-target organisms and water resources. In this study, NiO-GO is reported as an effective photocatalyst for the degradation of clothianidin in aqueous medium. Nickel oxide (NiO) nanoparticles were synthesized by a green method using Pisum sativum (pea) peel extract, which serves as a natural reducing and stabilizing agent, and subsequently integrated with graphene oxide (GO) through ultrasonication to form a NiO-GO composite in a 1:1 ratio. The materials were characterized by various techniques. Photocatalytic degradation of clothianidin under natural sunlight was systematically investigated, assessing the effects of pH, catalyst dosage, initial pollutant concentration, and agitation speed. The NiO-GO composite exhibited superior photocatalytic performance (96% degradation at pH 3 within 60 min) compared to pristine NiO and GO, with a rate constant 4.4 and 3.3 times higher, respectively. The as-prepared NiO-GO photocatalyst exhibited nearly consistent degradation efficiency over two successive cycles, demonstrating its excellent structural stability and reusability. The enhanced performance is attributed to improved charge separation afforded by GO support. This low-cost, green, and efficient NiO-GO photocatalyst demonstrates promising potential for sustainable pesticide remediation in aqueous environments. Full article

Climate change is impacting atmospheric patterns and therefore wave conditions, with ports being among the most affected infrastructures, making it crucial to ensure their operability under changing climatic conditions. Most scientific studies on climate change focus on coastal erosion and flooding, whereas research on its impact on port operability remains relatively scarce. This challenge could be tackled with the emergence of Artificial Intelligence (AI), where alternative modeling approaches can be developed. Thus, a novel AI-based model specifically designed for studying port agitation is introduced herein. By integrating a hybrid deep learning approach, combining Feedforward Neural Networks (FFNNs) to model wave climate and Convolutional Neural Networks (CNNs) for port image analysis, port agitation has been successfully predicted compared to linear wave propagation models. This marks the first instance of utilizing image processing tools to analyze port agitation, resulting in a model with a remarkably low error rate, while offering a significant reduction in computational time compared to traditional wave propagation models, reducing computational time by a factor of four to ten. The accuracy of the proposed model has been investigated and validated for the Port of Valencia, located in the Spanish section of the Mediterranean Sea. Full article

Background and Objectives: Although various regional anesthesia techniques are commonly used for laparoscopic cholecystectomy (LC), to date, no randomized controlled trial has compared the effectiveness of Quadratus Lumborum Plane Block (QLB) and External Oblique Intercostal Plane Block (EOIPB) in LC. Our aim was to compare the effectiveness of ultrasound-guided QLB and EOIPB in providing postoperative analgesia after LC. Materials and Methods: In this two-center, randomized controlled trial, patients undergoing LC were divided into QLB and EOIPB groups. Our primary outcome was the postoperative pain scores measured using the Numerical Rating Scale (NRS) at predetermined intervals. Secondary outcomes included opioid consumption, Riker Sedation–Agitation Scale (RSAS) score, and patient satisfaction. Results: The NRS pain scores at postoperative 30th minute, 4th, 12th, and 24th hours were significantly lower in the QLB group (p < 0.05). Patients in the QLB group required significantly less tramadol compared to the EOIPB group (p < 0.000). The QLB group also demonstrated lower RSAS scores (p = 0.005), indicating a smoother recovery process. Patient satisfaction scores were markedly higher in the QLB group (p < 0.000). Although both blocks were well-tolerated with no differences in side effects, EOIPB was associated with higher opioid consumption, indicating its relatively limited effectiveness. Conclusions: To conclude, this study highlights that QLB is a more effective option for postoperative analgesia and improves patient satisfaction after LC. EOIPB may serve as a viable alternative for some patients; however, given the advantages of QLB in pain control and recovery, it stands out as a more preferable method. Full article

Copper is one of the most used metals today due to its wide range of applications. Traditionally, this metal has been primarily extracted through pyrometallurgical methods, which presents several environmental and energy-related drawbacks. An alternative is hydrometallurgy, which has achieved acceptable copper extraction rates. However, this process has not found widespread industrial application due to operational challenges and the complexity associated with the selective recovery of copper ions from the Pregnant Leach Solution (PLS), especially due to the coexistence of copper and iron ions, complicating the efficient separation of both metals. In this work, the use of aluminum shavings as a cementation agent is proposed, analyzing variables such as the initial shaving concentration (2.5, 5, 10, 15, and 20 g/L), the agitation speed (0, 200, and 400 rpm), and a temperature of 20, 30, and 40 °C. The results demonstrated selective copper cementation, achieving a 100% recovery in 30 min under stirring conditions of 400 rpm. The analysis performed using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) revealed the formation of solid phases such as metallic copper (Cu), aluminum hydroxide [Al(OH)₃], and elemental sulfur (S). Additionally, it was observed that the iron ion concentration remained constant throughout the experiment, indicating a high selectivity in the process. The kinetic analysis revealed that the reaction follows a first-order model without stirring. An activation energy of 62.6 kJ/mol was determined within the experimental temperature range of 20–40 °C, confirming that the process fits the chemical reaction model. These findings provide a deeper understanding of the system’s behavior, highlighting its feasibility and potential for industrial-scale applications. Full article

Fungal mycelial pellets (MPs) exhibit high biomass-loading capacity; however, their application in wastewater treatment is constrained by structural fragility and the risk of environmental dispersion. To overcome these limitations, a dual-crosslinked polyvinyl alcohol–alginate gel (10% PVA, 2% sodium alginate) embedding strategy was developed and stabilized using 2% CaCl₂ and saturated boric acid. This encapsulation enhanced the tensile strength of MPs by 499% (310.4 vs. 62.1 kPa) and improved their settling velocity by 2.3-fold (1.12 vs. 0.49 cm/s), which was critical for stability under turbulent bioreactor conditions. Following encapsulation, the specific oxygen uptake rates (SOURs) of three fungal strains (F557, Y3, and F507) decreased by 30.3%, 54.8%, and 48.3%, respectively, while maintaining metabolic functionality. SEM revealed tight adhesion between the gel layer and both surface and internal hyphae, with the preservation of porous channels conducive to microbial colonization. In sequential-batch reactors treating sulfamethoxazole (SMX)-contaminated wastewater, gel-encapsulated MPs combined with acclimated sludge consistently achieved 72–75% SMX removal efficiency over six cycles, outperforming uncoated MPs (efficiency decreased from 81.2% to 58.7%) and pure gel–sludge composites (34–39%). The gel coating inhibited hyphal dispersion by over 90% and resisted mechanical disintegration under 24 h agitation. This approach offers a scalable and environmentally sustainable means of enhancing MPs’ operational stability in continuous-flow systems while mitigating fungal dissemination risks. Full article

Canthaxanthin is a significant carotenoid that is synthesized by specific microorganisms. It has multiple functions and has been utilized in food and feed supply chains. This research focused on improving canthaxanthin production by Paracoccus bogoriensis PH1, an orange-pigmented bacterium isolated from hot springs. Canthaxanthin production was optimized in flask-scale cultures by varying the pH, temperature, nutritional sources, aeration rates, and agitation techniques. Flask culture cultivation indicated that canthaxanthin production by this strain was influenced by pH stress mechanisms, resulting in the establishment of a two-stage pH control (pH-shift) technique to enhance cell mass and pigment production. The optimum flask conditions were refined for application in a 1 L bioreactor. An optimized cultivation procedure was established utilizing a Polypeptone Sucrose Yeast Extract (PPSYE) medium, with a pH transition from 7 to 11, incubation at 40 °C, agitation at 250 rpm, and aeration at 2 vvm for 48 h. This process resulted in a 3.12-fold increase in total carotenoid content and a 1.61-fold increase in canthaxanthin production, achieving 0.84 ± 0.06 mg/L compared to pre-optimized flask cultures in TSYEB medium (pH 7 at 37 °C, 72 h). Purified canthaxanthin from P. bogoriensis PH1 exhibited antioxidant activity in the ABTS assay. Full article

Azotobacter vinelandii OP is a bacterium that can produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P3HBV), a biodegradable and biocompatible polymer with applications in the biomedical field. This study aimed to evaluate P3HBV production and its 3-hydroxyvalerate (3HV) fraction under different agitation rates and oxygen uptake rates (q_O2) in chemostat cultures of A. vinelandii OP. Steady-state conditions with either oxygen or carbon limitation were established by modulating the agitation rates. Under oxygen-limited conditions (low q_O2 values) biomass and P3HBV concentrations increased to 3.3 g L⁻¹ and 2.1 g L⁻¹, respectively. At higher q_O2 values, the chemostat cultures were limited by carbon, and P3HBV content decreased from 62% to 33% (w w⁻¹). The highest 3HV molar fractions, 33.7 and 36.4 mol %, were observed at both the lowest and highest q_O2 levels, possibly linked to comparable valeric acid consumption rates. An elevated NAD(P)H/NAD(P)⁺ ratio was also observed under oxygen limitation, favoring polymer accumulation by indicating a more favorable intracellular redox state. These findings highlight the impact of nutrient limitation and respiratory activity on the biosynthesis of P3HBV and the 3HV composition by Azotobacter vinelandii OP. Such insights can support the development of tailored bioprocesses to modulate polymer characteristics, enabling a broader range of potential biomedical applications for P3HBV. Full article

Objective: The objective of this study was to develop a Physiologically Based Biopharmaceutics Modeling (PBBM) framework that can predict PK profiles in humans based on data generated from the BE Checker. Methods: Metoprolol and dipyridamole were selected as model drugs. A mathematical model was developed to describe drug dissolution, membrane permeation, and dynamic changes in pH and fluid volume within the BE Checker system. Using data generated under various experimental conditions, dissolution rate constants were estimated. For dipyridamole, the precipitation rate constant was also estimated, assuming simultaneous dissolution and precipitation processes. The estimated parameters were subsequently incorporated into the human PBBM to simulate PK profiles. Finally, the predictive accuracy of PK parameters such as Cmax and AUC was assessed. Results: For metoprolol, the PK profiles using the paddle revolution rates of 100 and 200 rpm closely matched the observed human data, particularly for Cmax and AUC, a key indicator of BE. In the case of dipyridamole, accurate predictions of the mean human PK profile were achieved when using BE Checker data obtained under high paddle speed (200 rpm) and longer pre-FaSSIF infusion times (20–30 min). Conversely, simulations based on lower paddle speed (50 rpm) and shorter pre-FaSSIF infusion time (10 min) underestimated plasma concentrations in humans. Conclusions: These findings suggest that the combination of BE Checker data acquired under high agitation conditions and the in silico mathematical model developed in this study enables accurate prediction of average human PK profiles. Full article

Plant cell cultures offer a promising platform for producing valuable biomolecules, yet their use in bioreactors remains under-optimized. Compared to animal or microbial cells, plant cells grow more slowly, limiting productivity. A common bioprocess strategy to improve yields involves controlling dissolved oxygen (DO) levels. However, little research has focused on combining agitation and aeration to regulate oxygen in plant cell cultures within bioreactors. The aim of this study was to evaluate the impact of an oxygen cascade mixing agitation and aeration on plant cell growth in stirred-tank systems. By maintaining 30% DO through this approach, the specific growth rate (µ) increased from 0.082 d⁻¹ to 0.144 d⁻¹ on average in Nicotiana benthamiana cultures at the 2 L scale, decreasing batch lengths from 21 to 10 days. These conditions were successfully replicated in a 7 L stainless-steel pilot bioreactor using previous values of geometry, k_La and N_RE as scale-up criteria, obtaining a µ of 0.161 d⁻¹. These results demonstrate that plant cell cultures’ efficiency can be enhanced by using standard bioprocess parameters. While this work confirms the feasibility of cascade oxygen control for improvements in growth, further studies are needed to evaluate its specific impact on biomolecule production across different systems. Full article

A multiphase model of hydrothermal liquefaction (HTL) using the computational fluid dynamics coupling discrete element method (CFD-DEM) is used to simulate biocrude oil production from sludge flocs in a continuous stirred tank reactor (CSTR). Additionally, the influence of the agitator speed and the slurry flow rate on dynamic biocrude oil production is investigated through full transient CFD analysis in a scaled-up CSTR study. The kinetics of the HTL mechanism as a function of temperature, pressure, and residence time distribution were employed in the model through a user-defined function (UDF). The multiphysics simulation of the HTL process in a stirred tank reactor using the Lagrangian–Eulerian (LE) approach, along with a standard k-ε turbulence model, integrated HTL kinetics. The simulation accounts for particle–fluid interactions by coupling CFD-derived hydrodynamic fields with discrete particle motion, enabling prediction of individual particle trajectories based on drag, buoyancy, and interphase momentum exchange. The three-phase flow using a compressible non-ideal gas model and multiphase interaction as design requirements increased process efficiency in high-pressure and high-temperature model conditions. Full article

To address the critical challenges of severe fragmentation in cuttings, persistent cuttings bed accumulation, and abrupt friction torque increases during horizontal well drilling of Jurassic continental shale oil formations in J Block, Sichuan Basin—rooted in the unique high clay content that induces colloidal stability of fine cuttings and resistance to conventional cleaning—this study innovatively proposes a coupled prevention–removal hole-cleaning technology. The core methodology integrates three synergistic components: (1) orthogonal numerical simulations to optimize drilling parameters, reducing the cuttings input rate by 43.48% through “hydraulic carrying + mechanical agitation” synergy; (2) a modified Moore model with horizontal section correction factors to quantify slip velocity of cuttings, lowering the prediction error from ±20% to ±5%; and (3) a helical groove cutting removal sub with 60 m optimal spacing, enhancing local turbulence intensity by 42% to disrupt residual cuttings bed. Field validation in Well J110-8-1H demonstrated remarkable improvements: a 50% reduction in sliding friction, a 25% decrease in rotational torque, and 40% shortening of the drilling cycle. This integrated technology fills the gap in addressing the “fragmentation–colloidal stability” dilemma in shale with high clay contents, providing a quantifiable solution for safe and efficient drilling in similar continental formations. Full article

The copper oxide ore in Zambia exhibits complex mineralogical characteristics, with copper primarily occurring in mica. The local hydrometallurgical plant employs heating–agitation acid leaching, which is hindered by a low leaching rate and prolonged leaching period, resulting in high energy consumption. To enhance the copper leaching efficiency, a systematic study was conducted on the use of organic cationic surfactants to enhance the leaching of the copper oxide ore. The results indicated that the primary copper-bearing mineral in the raw ore is cupriferous biotite, which is the reason for the difficulty in leaching. Under optimal conditions: a sulfuric acid dosage of 45 kg/t, a CTAB dosage of 75 g/t, a leaching temperature of 65 °C, a liquid-to-solid ratio of 2:1, and a leaching time of 120 min, the copper leaching rate reached 78.32%. Compared to the optimal result of regular heating–agitation acid leaching, this approach increased the copper leaching rate by 3.06%, reduced the leaching time by 80 min, and lowered leaching energy consumption without destroying the structure of cupriferous biotite. Mechanistic studies show that organic cations in CTAB neutralize excess anions, thereby weakening the electrostatic Coulomb forces between the interlayer cations and the hexagonal structure. This increases the interlayer spacing of biotite, facilitating the entry of H⁺ from sulfuric acid into the interlayer. The H⁺ then reacts with the copper in the biotite, enhancing the copper leaching rate and reducing leaching time. Because CTAB has high degradability, it will not cause persistent pollution to the environment. The use of CTAB as a leaching aid can reduce the energy consumption of heating–agitation acid leaching and reduce the heating cost per ton of ore by USD 6.11–9.36. Full article

High-gradient magnetic separation is a key step in the pre-concentration of ilmenite before flotation, particularly in the gravity separation process. However, as the amount of weakly magnetic gangue minerals increases, the grade of the coarse concentrate from high-gradient magnetic separation decreases. This paper investigates the mineralogical factors affecting the enrichment efficiency of high-gradient magnetic separation. Additionally, a newly developed stirred fluidized bed device, an agitated reflux classifier (ARC), was successfully applied to remove weakly magnetic gangue minerals that are difficult to separate by high-gradient magnetic separation (HGMS). For low-grade ilmenite with a feed grade of 3.97%, a combined process of magnetic separation and gravity separation was employed, achieving a concentrate with a grade of 16.50% and a recovery rate of 54.11%. This concentrate meets the requirements for flotation feed. This study provides a new approach for the beneficiation of low-grade ilmenite. Full article

Background/Objectives: Haloperidol is a typical antipsychotic drug widely used for acute confusional state, psychotic disorders, agitation, delirium, and aggressive behavior. Methods: The toxicity of haloperidol was studied using zebrafish (ZF) embryos as a model organism. Dechorionated embryos were exposed to various concentrations of haloperidol (0.5–6.0 mg/L). The lethal dose concentration was estimated and was found to be 1.941 mg/L. Results: The impact of haloperidol was dose-dependent and significant from 0.25 mg/L. Haloperidol induced several deformities at sublethal doses, including abnormal somites, yolk sac edema, and skeletal deformities. Haloperidol significantly affected heart rate and blood flow and induced pericardial edema and hyperemia in a dose-dependent manner, suggesting its influence on heart development and function. Embryos exposed to haloperidol during their ontogenetic development had smaller body length and eye surface area than non-exposed ones in a dose-dependent manner. Conclusions: It was found that haloperidol significantly affects the behavior of the experimental organisms in terms of mobility, reflexes to stimuli, and adaptation to dark/light conditions. Full article

This study analyzes the aromatic profiles of kiwi-based fermented beverages, inoculated with varying proportions of milk kefir grains and incubated under different shaking rates. The experiments were designed using response surface methodology and three consecutive batch cultures were performed under each experimental condition. At the end of each fermentation, the grains were separated from the beverage and reused as the inoculum for fermenting fresh kiwi juice in the subsequent batch. Based on the results, together with the previously determined microbiological and chemical characteristics, two beverages were identified as having broader aromatic profiles, lower contents of sugars, ethanol, and acids, and high counts of lactic acid bacteria (LAB) and yeasts (>10⁶ CFU/mL). These beverages were produced under relatively low agitation rates (38 and 86 rpm) and high inoculum proportions (4.33% and 4.68% w/v) during the second and third batch cultures, respectively. Over 28 days of refrigerated storage, the pH values of both beverages remained relatively stable, and the LAB counts consistently exceeded 10⁶ CFU/mL. Yeast counts, along with the production of ethanol, glycerol, lactic acid, and acetic acid, increased slightly over time. In contrast, the concentrations of citric acid, quinic acid, total sugars, and acetic acid bacteria declined by day 28. Full article