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Ionically crosslinked hydrogels containing metal coordination motifs have piqued the interest of researchers in recent decades due to their self-healing and adhesive properties. In particular, catechol-functionalized bulk hydrogels have received a lot of attention because of their bioinspired nature. By contrast, very little is known about thin viscoelastic membranes made using similar chelator–ion pair motifs. This shortcoming is surprising because the unique interfacial properties of these membranes, namely, their self-healing and adhesion, would be ideal for capsule shells, adhesives, or for drug delivery purposes. We recently demonstrated the feasibility to fabricate 10 nm thick viscoelastic membranes from catechol-functionalized surfactants that are ionically crosslinked at the liquid/liquid interface. However, it is unclear if the vast know-how existing on the influence of the chelator–ion pair on the mechanical properties of ionically crosslinked three-dimensional (3D) hydrogels can be translated to two-dimensional (2D) systems. To address this question, we compare the dynamic mechanical properties of ionically crosslinked pyrogallol functionalized hydrogels with those of viscoelastic membranes that are crosslinked using the same chelator–ion pairs. We demonstrate that the storage and loss moduli of viscoelastic membranes follow a trend similar to that of the hydrogels, with the membrane becoming stronger as the ion–chelator affinity increases. Yet, membranes relax significantly faster than bulk equivalents. These insights enable the targeted design of viscoelastic, adhesive, self-healing membranes possessing tunable mechanical properties. Such capsules can potentially be used, for example, in cosmetics, as granular inks, or with additional work that includes replacing the fluorinated block by a hydrocarbon-based one in drug delivery and food applications.

Drilling the wellbore into subsurface formations is the earliest stage in the life of a well that requires a suitable drilling fluid with good rheological and filtration control characteristics to achieve a successful drilling operation. This paper reports on the formulation of water-based drilling mud using kaolin clay reinforced with biopolymer, surfactant, and limestone from Tanzania. The raw materials used for the formulation were characterized using XRD, XRF, FTIR, and TGA techniques. The rheological properties, filtration loss, pH, and density of the formulated mud were measured using a viscometer, filter press, pH meter, and mud balance, respectively. The XRD results revealed kaolinite and quartz as the main minerals in all kaolin clay samples which were in agreement with the FTIR findings. The mineralogical composition of the kaolin was observed to vary with the mining sites and influenced the rheological and filtration control characteristics of the mud. The beneficiated drilling mud showed better rheological and filtration control characteristics than the commercially available bentonite mud in Dar es Salaam market and was comparable with the API standards. These results, therefore, are not only new but rather important and novel information on the potential of kaolin clay for the formulation of water based drilling mud. Keywords: Water-based drilling mud, kaolin clay, biopolymers, bentonite, surfactant

Background: Clinical and radiographic criteria are traditionally used to determine the need for surfactant therapy in preterm infants. Lung ultrasound is a bedside test that offers a rapid, radiation-free, alternative to this approach. Objective: To conduct a systematic review and meta-analysis to determine the accuracy of a lung ultrasound score (LUS) in identifying infants who would receive at least one surfactant dose. Secondary aims were to evaluate the predictive accuracy for ≥2 doses and the accuracy of a different image classification system based on three lung ultrasound profiles. Methods: PubMed, SCOPUS, Biomed Central, and the Cochrane library between January 2011 and December 2021 were searched. Full articles enrolling preterm neonates who underwent lung ultrasound to predict surfactant administration were assessed and analyzed following Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and QUADAS-2 guidelines. Results: Seven prospective studies recruiting 697 infants met the inclusion criteria. Risk of bias was generally low. Oxygen requirement, clinical and radiographic signs of respiratory distress syndrome were used as reference standards for surfactant replacement. The summary receiver operator characteristic (sROC) curve for LUS predicting first surfactant dose showed an area under the curve (AUC) = 0.88 (95% confidence interval [CI]: 0.82-0.91); optimal specificity and sensitivity (Youden index) were 0.83 and 0.81 respectively. Pooled estimates of sensitivity, specificity, diagnostic odds ratio, negative predictive value, and positive predictive value for LUS predicting the first surfactant dose were 0.89 (0.82-0.95), 0.86 (0.78-0.95), 3.78 (3.05-4.50), 0.92 (0.87-0.97), 0.79 (0.65-0.92). The sROC curve for the accuracy of Type 1 lung profile in predicting first surfactant dose showed an AUC of 0.88; optimal specificity and sensitivity were both 0.86. Two studies addressing the predictive accuracy of LUS for ≥2 surfactant doses had high heterogeneity and were unsuitable to combine in a meta-analysis. Discussion: Despite current significant variation in LUS thresholds, lung ultrasound is highly predictive of the need for early surfactant replacement. This evidence was derived from studies with homogeneous patient characteristics and low risk of bias.

Self-emulsifying drug delivery system (SEDDS), a type of lipid-based technology which are isotropic mixtures of oil, surfactant, solvent, and co-solvents generated by the activity of liquid or solid self-emulsifying ingredients onto powders. It shown interest in the recently for enhancement of solubility and bioavailability of poorly water-soluble drugs (BCS-II). With the novelty of research in this field, novel Excipients have been design with novel properties for enhances solubility, Bioavailabity and oral absorption to achieving target response. Self-emulsifying drug delivery systems (SEDDS) emerged as an insightful approach for delivering highly hydrophobic entities to enhance their bioavailability. SEDDS increase drug bioavailability in addition to improving the solubility of poorly soluble drugs by a number of additional potential pathways, such as avoiding the hepatic first-pass effect, blocking P-gp efflux, and overcoming resistance to metabolism by the cytochrome P450 family of enzymes in the gut and liver. Conventional SEDDS were developed in a liquid form which owned numerous overcome like low stability and drug loading efficiency, fewer choices of dosage forms and irreversible precipitation of drug or excipients. To address these curbs solid-SEDDS (S-SEDDS) was introduced as an efficient strategy that combined advantages of solid dosage forms such as increased stability, portability and patient compliance along with substantial improvement in the bioavailability. This review highlights parts of SEDDS, and their characterization evaluation. Which are completely summarized via different techniques.

Prematürelerde görülen respiratuvar distres sendromunda surfaktanın klinik kullanıma girmesi ile birlikte prematüre bebeklerdeki yaşam oranı dramatik olarak artmıştır. Surfaktanın akciğerlere iletiminde kullanılan yöntemler zaman içerisinde daha az invaziv ve hatta invaziv olmayan yöntemlere doğru evrilmeye başlamıştır. Surfaktanın ince kateter ile uygulanması, bir larengeal veya suproglottik havayolu cihazı kullanılarak, farengeal uygulama ile ve aerosolize şekilde verilmesi gibi yeni yöntem çalışmaları giderek artmaktadır. Böylece, immatür akciğerin klasik olarak kabul edilen entübasyon, pozitif basınçlı ventilasyon ve mekanik ventilasyonun zararlı etkilerinden korunması hedeflenmiştir. İnce kateter ile surfaktan uygulanması metodu ile yapılan çok sayıda çalışma ve meta-analizin sonuçları entübasyon, surfaktan uygulanması ve pozitif basınçlı ventilasyon metotları ile karşılaştırıldığında mekanik ventilasyon ihtiyacı ve süresi, bronkopulmoner displazi insidansı ve neonatal mortalite oranlarında azalmaya neden olduğu gösterilmiştir. Ancak çalışmalarda premedikasyon yönetimi ve solunum desteği türü, uygulanan surfaktan türü gibi birçok konuda heterojenite mevcuttur. Supraglottik hava yolu cihazı, farengeal uygulama ve aerosolizasyon uygulamaları özellikle laringoskopinin dezavantajlarını ortadan kaldırması ve daha da az invaziv olmaları, daha az tecrübe ve yetenek gerektirmeleri nedenleri ile ince kateter ile surfaktan uygulanması yönteminden avantajlı olsalar da henüz rutin klinik kullanıma girmeleri için daha fazla veriye ihtiyaç vardır., The survival rate of premature infants has increased dramatically, after the beginning of surfactant use in newborn clinics for premature infants with respiratory distress syndrome. The surfactant delivery methods to the lungs have started to evolve into less invasive and even non-invasive methods over the time. Studies on new methods such as thin catheter surfactant administration, laryngeal or supraglottic airway device, pharyngeal instillation, and aerosolized techniques are increasing. The purpose of the less invasive or noninvasive methods is the protection of immature lungs from harmful effects of intubation, positive pressure ventilation and invasive mechanical ventilation. It has been reported in many studies and meta-analysis that TCA methods were related to lower need of mechanical ventilation, shorter duration of mechanical ventilation, and lower incidence of bronchopulmonary dysplasia or death, compared to intubation, surfactant, and positive pressure ventilation methods. However, there are heterogeneities in premedication policies and respiratory support type, and the type of surfactant applied in the studies. Laryngeal or supraglottic airway device, pharyngeal instillation, and aerosolized techniques have advantages over thin catheter, because they eliminate the disadvantages of laryngoscopy, they are less invasive than thin catheter and they require minimal experience and skills, but more data are needed for routine clinical use of these new methods.

The article discusses the process of formation of deposits in the pipelines of the engine oil system and the factors affecting the conditions for their formation. The technological process of oxidation and the criteria for indicator parameters characterizing the thermolysis of used oil are shown. An extractive method is proposed that ensures the removal of deposits from the pipeline using special flushing process fluids based on regenerated petroleum oil. To search for cheap and efficient hydrocarbon raw materials, regenerated petroleum oils were chosen from among the renewable resources of oil refining. The proposed process fluid was prepared on the basis of low-viscosity spent and then purified petroleum oil. The viscosity of the petroleum oil was adjusted with the addition of petroleum kerosene or diesel. Diluted surfactant solutions were used as additives. and detergent additive (alkali metal salts). It was revealed that in the oil system of an automobile engine at high temperatures (200-3500C) oil thermolysis occurs, and the resulting deposits contain asphaltenes, carbons and carboids. The efficiency of dissolution of deposits in the mixture under study at low temperatures and the concentration of surfactants were revealed. The dependence of the interfacial tension on the concentration of various surfactants is shown. The limiting amounts of the content of the constituent components are found and the ratio of oily extract, from deposits of oxidized oil, is selected. As a result of the tests, it was found that the washing liquid reduces the interfacial tension between the surface of the pipes and deposits and leads to an increase in the movement of the liquid. It has been established that the process of washing off deposits depends on the composition of the deposits, as well as on the composition of the oily extract. The optimal mode and prescription composition of the flushing liquid has been selected. The efficiency of washing off the studied liquid with other means is shown, while it should be noted that this liquid has a simple component composition and is much cheaper than other means.

The traditional extraction methods used to recover natural antioxidants from food industry wastes involve significant amounts of hazardous solvents. A viable alternative is the use of non-toxic surfactants to remove organic compounds from wastes at temperatures above the cloud point. Cloud point extraction has only recently begun to be used to recover high-value added compounds from food industry wastes. In the current work, a method for the isolation of high-value added components from liquid tomato wastewater using a cloud point extraction method was developed and optimized. Food-grade lecithin was examined for its potential to be used as a surfactant in the developed procedure. Moreover, parameters affecting the extraction (ionic strength, sample pH, temperature of extraction, and surfactant concentration) were examined and optimized. According to the results, the maximum recovery of carotenoids from the sample could be achieved with the developed procedure, by simply adjusting the pH to 3.5, adding 35.6% (w/v) sodium chloride, and setting the temperature at 45 °C. Moreover, the amount of lecithin used was examined. In order to extract the total amount of carotenoids from a sample, it was found that either three extractions with 1% lecithin are needed, or two extractions with 2% lecithin. In addition, the antioxidant activity of the extract was examined and it was found to scavenge 36.3% of DPPH free radicals. This percentage was 10% lower compared to the initial sample, which suggests that the extracted compounds retain their activity. Overall, the developed procedure can be used to recover carotenoids in a cost-efficient and easy way.

HYPOTHESIS: Predicting the surface tension (SFT)-log(c) profiles of hydrocarbon surfactants in aqueous solution is computationally non-trivial, and empirically challenging due to the diverse and complex architecture and interactions of surfactant molecules. Machine learning (ML), combining a data-based and knowledge-based approach, can provide a powerful means to relate molecular descriptors to SFT profiles. EXPERIMENTS: A dataset of SFT for 154 model hydrocarbon surfactants at 20-30 °C is fitted to the Szyszkowski equation to extract three characteristic parameters (Γmax,KL and critical micelle concentration (CMC)) which are correlated to a series of 2D and 3D molecular descriptors. Key (∼10) descriptors were selected by removing co-correlation, and employing a gradient-boosted regressor model to rank feature importance and carry out recursive feature elimination (RFE). The hyperparameters of each target-variable model were fine-tuned using a randomised cross-validated grid search, to improve predictive ability and reduce overfitting. FINDINGS: The ML models correlate favourably with test experimental data, with R2= 0.69-0.87, and the merits and limitations of the approach are discussed based on 'unseen' hydrocarbon surfactants. The incorporation of a knowledge-based framework provides an appropriate smoothing of the experimental data which simplifies the data-driven approach and enhances its generality. Open-source codes and a brief tutorial are provided.

Due to the continuous depletion of crude oils in the reserves, and continuous rise in energy demand, there is currently a widespread interest in various methods of chemical enhanced oil recovery (EOR). Surfactants flooding improves oil recovery by combining various mechanisms and this approach has proven to be effective. Surfactant flooding is still threatened by problems which are unstable under excessive adsorption and harsh reservoir conditions. Research has shown that anionic surfactant is most preferred for EOR specifically with sandstone reservoirs. In some cases, after injecting non-ionic, cationic, or both surfactants, into the carbonate reservoirs, better performance has been documented. To produce surfactants for reservoirs with properties such as high/ultra-high temperature, ultra/high oil viscosity, ultra-high salinity, and low/extra-low permeability, new knowledge is needed. An ideal surfactant with highest recovery should possess larger IFT reduction, wettability alteration, and asphaltene inhibition capabilities. This review provides an experimental study on surfactant application to conventional and unconventional reservoirs for EOR. Thus, establishing a good foundation for preparing and designing prospective field-scale chemical supported EOR systems. Furthermore, this study presents the influence of oilfield element variation during surfactant flooding, types and EOR mechanisms, its application in unconventional reservoirs, surfactant adsorption and adsorption mitigation, surfactant phase behavior etc.

The hydrodynamics of thin films is an important factor when it comes to the stability and rheology of multiphasic materials, such as foams, emulsions, and polymer blends. However, there have so far been only limited experimental studies addressing the dynamics of individual free-standing thin films at conditions similar to those encountered on macroscopic scales. In this article, we study a well-characterized system of a water-in-oil emulsion stabilized by a non-ionic surfactant (SPAN80) close to its CMC. We employ a dynamic thin film balance, to study the dynamics of freestanding films under both constant and time-varied pressure drops. We compare with the recently published results of Narayan et al. (2020) on colliding droplets of the same system with a hydrodynamic microfluidic trap, and show for the first time that agreement between the two lengthscales is possible, which indicates that the coalescence is indeed dominated by the dynamics in the film. We then address the scatter in the coalescence times and show that it can be affected by extrinsic factors, as well as by variations in the collision angle. Finally, we discuss the difficulties of extracting insight on the coalescence mechanism from coalescence time distributions when different effects such as impurities, small pressure variations, collision angle variations, and possible Marangoni-related instabilities are at play., Rheologica Acta, 61 (10), ISSN:0035-4511, ISSN:1435-1528

[ES] La presente tesis doctoral se centra en la obtención, vía síntesis directa, de materiales zeolíticos nanocristalinos con propiedades fisicoquímicas y catalíticas mejoradas respecto a los materiales de referencia. Para ello se ha hecho uso de tensioativos creados específicamente para cada una de las estructuras zeolíticas estudiadas, evitando el uso de procesos post-sintéticos que conllevan una pérdida de material cristalino. En la primera parte del trabajo se ha estudiado la obtención de la zeolita ITQ-2 deslaminada por síntesis directa (DS-ITQ-2) mediante el uso de varios tensioactivos, siendo el C16DC1 (N-Hexadecil-N'-metil-1,4-diazabiciclo[2.2.2]octano) con el que mejores resultados se han obtenido. Se ha estudiado la influencia de la longitud de la cadena alifática y la concentración del agente director de estructura orgánico (ADEO) en el gel de síntesis sobre la cinética del proceso de cristalización y las implicaciones sobre las características fisicoquímicas del material obtenido. Mediante el control de la concentración del tensioactivo en el gel de síntesis, ha sido posible dirigir el grado de deslaminación del material final. Las propiedades fisicoquímicas del material considerado como óptimo se han comparado con las de las zeolitas MCM-22, MCM-56 e ITQ-2, todas ellas con la misma estructura cristalina (MWW). Por último, la actividad catalítica de la zeolita DS-ITQ-2 se ha estudiado en dos reacciones, la alquilación de benceno con propileno para la obtención de cumeno y la reacción de 2,5-dimetilfurano con etileno para la obtención de p-xileno, obteniendo en ambos casos unos resultados de conversión y selectividad excelentes. La segunda parte de la tesis se ha centrado en la preparación de la zeolita ferrierita en su forma nanocristalina por síntesis directa mediante la utilización de tensioactivos. Se han estudiado tensioactivos con tres partes polares diferentes obtenidos a partir de las correspondientes aminas utilizadas como ADEOs. Además, también se ha estudiado el efecto de la longitud de la cadena del tensioactivo entre los 6 y los 16 átomos de carbono. La modificación de parámetros del gel de síntesis como por ejemplo la relación molar entre la piperidina o el tensioactivo y la sílice ha resultado ser determinante a la hora de conseguir una composición óptima para la obtención de la zeolita nanocristalina con las propiedades fisicoquímicas deseadas. La optimización de la temperatura de síntesis y la introducción de cristales de siembra en el gel de síntesis ha permitido mejorar las propiedades finales del material. La actividad catalítica de las nanoferrieritas se ha estudiado en dos reacciones diferentes, la oligomerización de 1-penteno y la isomerización de 1-buteno. Se ha mostrado la importancia de reducir el tamaño del cristal de la ferrierita, obteniéndose materiales con actividad y selectividad muy superior a los descritos en la bibliografía abierta y de patentes., [CA] La present tesis doctoral es centra en l'obtenció, via síntesi directa, de materials zeolítics nanocristalins amb propietats fisicoquímiques i catalítiques millorades respecte als materiales de referència. Per a això s'ha fet ús de tensioatius creats específicament per a cadascuna de les estructures zeolítiques estudiades, evitant l'ús de processos post-sintètics que comporten una pèrdua de material cristal·lí. En la primera part del treball s'ha estudiat l'obtenció de la zeolita ITQ-2 deslaminada per síntesi directa (DS-ITQ-2) mitjançant l'ús de diversos tensioactius, essent el C16DC1 (N-Hexadecil-N'-metil-1,4-diazabiciclo[2.2.2]octà) amb el que millors resultats s'han obtés. S'ha estudiat la influència de la longitud de la cadena alifàtica i la concentració de l'agent director d'estructura orgànic (ADEO) en el gel de síntesi sobre la cinètica del procés de cristal·lització i les implicacions sobre les característiques fisicoquímiques del material obtés. Mitjançant el control de la concentració del tensioactiu en el gel de síntesi, ha sigut possible dirigir el grau de deslaminació del material final. Les propietats fisicoquímiques del material considerat com òptim s'han comparat amb les de les zeolites MCM-22, MCM-56 i ITQ-2, totes elles amb la mateixa estructura cristal·lina (MWW). Per íltim, l'activitat catalítica de la zeolita DS-ITQ-2 s'ha estudiat en dos reaccions, l'alquilació de benzé amb propilé per a l'obtenció de cumé i la reacció de 2,5-dimetilfurà amb etilé per a l'obtenció de p-xilé, obtenint en tots dos casos uns resultats de conversió i selectivitat excel·lents. La segona part de la tesi s'ha centrat en la preparació de la zeolita ferrierita a la seua forma nanocristal·lina per síntesi directa mitjançant la utilizació de tensioactius. S'han estudiat tensioactius amb tres parts polars diferents obtesos a partir de les corresponents amines utilitzades com a ADEOs. A més a més, també s'ha estudiat l'efecte de la longitud de la cadena del tensioactiu entre els 6 i els 16 àtoms de carboni. La modificació de paràmetres del gel de síntesi com per exemple la relació molar entre la piperidina o el tensioactiu i la sílice ha resultat ser determinant a l'hora de conseguir una composició òptima per a l'obtenció de la zeolita nanocristal·lina amb les propietats fisicoquímiques desitjades. L'optimització de la temperatura de síntesi i la introducció de cristalls de sembra en el gel de síntesi ha permés millorar les propietats finals del material. L'activitat catalítica de les nanoferrierites s'ha estudiat en dos reaccions diferents, l'oligomerizació de l'1-penté i la isomerització de l'1-buté. S'ha mostrat la import`ancia de reduir el tamany del cristall de la ferrierita, obtenint-se materials amb activitat i selectivitat molt superior als descrits en la bibliografia oberta i de patents., [EN] This doctoral thesis focuses on obtaining, via direct synthesis, nanocrystalline zeolite materials with improved physicochemical and catalytic properties compared to reference materials. For this, surfactants created specifically for each of the zeolite structures studied have been used, avoiding the use of post-synthetic processes that lead to a loss of crystalline material. In the first part of the work, the obtaining of the delaminated ITQ-2 zeolite by direct synthesis (DS-ITQ-2) through the use of various surfactants, being C16DC1 (NHexadecyl-N'-methyl-1,4-diazabiciclo[2.2.2]octane) with which the best results have been obtained. The influence of the length of the aliphatic chain and the concentration of the organic structure directing agent (OSDA) in the synthesis gel on the kinetics of the crystallization process and the implications on the physicochemical characteristics of the obtained material have been studied. By controlling the concentration of the surfactant in the synthesis gel, it has been possible to direct the degree of delamination of the final material. The physicochemical properties of the material considered optimal have been compared with those of the zeolite MCM-22, MCM-56 and ITQ-2, all of them with the same crystalline structure (MWW). Finally, the catalytic activity of the zeolite DS-ITQ-2 has been studied in two reactions, the alkylation of benzene with propylene to obtain cumene and the reaction of 2,5-dimethylfuran with ethylene to obtain p-xylene, obtaining excellent conversion and selectivity results in both cases. The second part of the thesis has focused on the preparation of ferrierite zeolite in its nanocrystalline form by direct synthesis using surfactants. Surfactants with three different polar parts, obtained from the corresponding amines used as OSDAs, have been studied. In addition, the effect of the chain length of the surfactant between 6 and 16 carbon atoms has also been studied. Modifying the parameters of the synthesis gel, such as the molar ratio between piperidine or surfactant and silica, has turned out to be decisive when it comes to achieving an optimal composition for obtaining nanocrystalline zeolite with the desired physicochemical properties. The optimization of the synthesis temperature and the introduction of seed crystals in the synthesis gel have allowed to improve the final properties of the material. The catalytic activity of nanoferrierites has been studied in two different reactions, the oligomerization of 1-pentene and the isomerization of 1-butene. The importance of reducing the size of the ferrierite crystal has been shown, obtaining materials with activity and selectivity much higher than those described in the open and patent literature.

The spectacular evolution of the urban and industrial sector today poses real environmental challenges of water pollution that requires immediate attention. Surfactants are emerging contaminants that pose a significant problem in wastewater treatment, and their presence causes difficulty in traditional treatment processes. In this context, the present work critically reviews the impacts of surfactants and their toxicity on the environment and human health while presenting the various techniques used in wastewater treatment plants to reduce their effects. Surfactants are removed from wastewater using different techniques, including physical, chemical, biological, and membrane treatment. The choice of the most appropriate technique for wastewater treatment is based on many criteria, such as effluent quality, standards to be respected, investment and operating costs, and environmental footprint. Adsorption and coagulation-flocculation are the most suitable techniques for removing detergents from wastewater due to their effectiveness, ease of use, environmental friendliness, and cost-effectiveness. This work is licensed under a Creative Commons Attribution 4.0 International License.

Objectives: To examine the success rate of less invasive surfactant administration (LISA), to identify early predictive factors for the outcome of LISA and to compare neonatal outcomes between the LISA failure group and the group of infants who were succesfully treated with LISA. Design: A retrospective cohort study. Patients: Infants born at less than 33 weeks of gestation (n=158) and treated with LISA for respiratory distress syndrome. Results: LISA was successful in 86 cases (54.4%), 72 preterm infants (45.6%) needed additional surfactant therapy and/or mechanical ventilation in the first 72 hours. In a multivariate logistic regression analysis, six independent predictors were identified: core temperature at the time of admission (adjusted OR 3.56), suboptimal dose of surfactant (adjusted OR 0.254), elevated CRP (>10 mg/L) at 24 hours of life (adjusted OR 0.28), highest respiratory severity score during the first hour of life or at the time of LISA (adjusted OR 0.463), maternal age (adjusted OR 0.923) and birth weight (adjusted OR 1.003). The ROC curve created by using the identified factors indicates good predictive power with an area under the curve of 0.85. LISA failure was associated with a substantially higher risk of pneumothorax, bronchopulmonary dysplasia, intraventricular hemorrhage, severe retinopathy of prematurity, longer duration of mechanical ventilation and prolonged length of hospital stay. Conclusion: Failure of LISA is relatively frequent event in very preterm infants and is associated with adverse outcomes. Prevention of hypothermia during early stabilization and appropriate dosing of surfactant increase may LISA success rates and improve patient outcome.

Funding Information: The authors are grateful for support from the Engineering and Physical Sciences Research Council in the form of a Strategic Equipment Grant EP/T006412/1 and DTP studentship for funding J D Tinkler’s research work. I. Martín-Fabiani is supported by a UK Research and Innovation Future Leaders Fellowship (MP/T02061X/1). Publisher Copyright: © 2022 American Chemical Society. The effects of particle interactions on the size segregation and assembly of colloidal mixtures during drying were investigated. A cationic surfactant was added to a binary latex/silica colloidal dispersion that has been shown to self-stratify upon drying at room temperature. Atomic force microscopy was used to show that the change in particle interactions due to the presence of surfactants reduced the degree of stratification and, in some cases, suppressed the effect altogether. Colloidal dispersions containing higher surfactant concentrations can undergo a complete morphology change, resulting instead in the formation of armored particles consisting of latex particles coated with smaller silica nanoparticles. To further prove that armored particles are produced and that stratification is suppressed, cross-sectional images were produced with energy-dispersive X-ray spectroscopy and confocal fluorescence microscopy. The growth of armored particles was also measured using dynamic light scattering. To complement this research, Brownian dynamics simulations were used to model the drying. By tuning the particle interactions to make them more attractive, the simulations showed the presence of armored particles, and the size segregation process was hindered. The prevention of segregation also results in enhanced transparency of the colloidal films. Overall, this research proves that there is a link between particle interactions and size segregation in drying colloidal blends and provides a valuable tool to control the assembly of different film architectures using an extremely simple method.

Context: A solution of simethicone administrated orally before the scan endoscopy procedure is recommended as a good means to reduce the bubbles interference. Aims: To evaluate the reliability, reproducibility and effectiveness of simethicone pre-treatment before endoscopic exploration of patients not diagnosed with malignant digestive pathologies. Methods: The study was organized in two stages. Time zero was a retrospective reanalysis of data from 58 randomized patients (age 15-90 years) who had been evaluated by endoscopy without simethicone (Control group), and 66 patients (Simethicone group) who were recruited and received 62 mL of a simethicone pre-preparation drink, 30 min before examination. The second stage, using procedure with simethicone, was continued and after 6 months at the beginning, 88 subjects were randomized. Stability in the results was demonstrated with simethicone. Statistical analysis was performed using SPSS v.21. Results: Analysis of comorbidities were represented with the highest prevalence being high blood pressure, diabetes mellitus, long-term depression, obesity and hypothyroidism. Results demonstrated similarity among endoscopist and between analysts within the same group (examination time, images resolved and with the best quality, by mucosal areas). However, these variables were different between groups, such that valuation quality was improved with simethicone, even 6 months after the initial evaluation. Conclusions: Use of simethicone as a pre-preparation drink 30 min before the endoscopy evaluation improves the quality of images and reduces the time of operation.

The mechanisms involved in cleaning a heterogeneous, multicomponent baked food soil off stainless steel surfaces in aqueous solutions were investigated using novel tools to quantify changes in the soil in situ and in real time: fluid dynamic gauging (thickness, voidage); millimanipulation (adhesive strength, removal force); TOC assays (soil leaching); and droplet image analysis (fat and oil release). Swelling of the soil was accompanied by a reduction in soil strength and preceded the release of oil droplets: the latter did not affect removal forces. The effect of pH, temperature, and surfactants (CTAB, SDBS and TX-100) was investigated and quantified using simple zeroth and first order kinetic models. Whilst increasing temperature from 20°C to 50°C enhanced swelling and reduced adhesion forces, the impact of pH and surfactant varied and simple rules to predict cleaning of this complex food soil could not be extracted.

Understanding pulmonary diseases requires robust culture models that are reproducible, sustainable in long-term culture, physiologically relevant, and suitable for assessment of therapeutic interventions. Primary human lung cells are physiologically relevant but cannot be cultured in vitro long term and, although engineered organoids are an attractive choice, they do not phenotypically recapitulate the lung parenchyma; overall, these models do not allow for the generation of reliable disease models. Recently, we described a new cell culture platform based on H441 cells that are grown at the air-liquid interface to produce the SALI culture model, for studying and correcting the rare interstitial lung disease surfactant protein B (SPB) deficiency. Here, we report the characterization of the effects of SALI culture conditions on the transcriptional profile of the constituent H441 cells. We further analyze the transcriptomics of the model in the context of surfactant metabolism and the disease phenotype through SFTPB knockout SALI cultures. By comparing the gene expression profile of SALI cultures with that of human lung parenchyma obtained via single-cell RNA sequencing, we found that SALI cultures are remarkably similar to human alveolar type II cells, implying clinical relevance of the SALI culture platform as a non-diseased human lung alveolar cell model., Graphical abstract, The authors investigate the transcriptome of their established human pulmonary cell culture model (SALI) that recapitulates alveolar cell markers. RNA-seq analysis reveals striking parallels between gene expression profiles of SALI culture and primary ATII cells. The findings underline the suitability of SALI culture as a clinically relevant proxy for alveolar epithelium.

Introduction: Meconium staining of amniotic fluid (MSAF) is a natural phenomenon in pregnant mothers and their fetuses. MSAF may lead to developing Meconium Aspiration Syndrome (MAS). Surfactant replacement therapy has recently emerged as a therapy in MAS, but no guideline outlines how to administer it properly. Case Presentation: We present two term neonates with severe MAS cases focusing on the bolus surfactant replacement therapy. The first baby was given surfactant at 23 hours after birth and the second baby at 8 hours after birth. We used Survanta (beractant) in the dose of 100 mg/kg BW in both cases. Clinical improvement was observed 24 hours after surfactant bolus administration with different clinical characteristics, treatment approaches, and outcomes.Conclusion: In conclusion, therapeutic surfactant bolus in severe MAS may improve outcomes without significant adverse side effects.

Capillary forces result in the trapping of the oleic phase in porous media even after extensive flushing with brine. Alkali-surfactant-polymer formulations drastically diminish capillary forces, whereas adding polymer to the water phase increases viscous forces, resulting in highly efficient extraction of the residual oil. However, by virtue of its scale, the above process requires a large quantity of chemicals, which poses a threat to the environment. Here, we demonstrate that replacing the polymer with a gas such as nitrogen, flue gas, or carbon dioxide achieves equally superior oil extraction efficiency when using a much smaller amount of chemicals. Mobilized oil is first displaced as a continuous phase (oil-bank) and then as an oil-in-water dispersion. Microflow visualization experiments reveal that dispersed oil spreads at the gas–liquid interface (surfactant solutions) due to the presence of adsorbed surfactant molecules. Our dry-cleaning extraction of hydrocarbons has a wide spectrum of applications and is particularly useful for the production of hydrocarbons from underground formations while mitigating the impact of chemicals on the environment.

In this work, hydrogels formed by interaction of biopolymeric electrolytes and oppositely charged surfactants are studied from the point of view of their ability to incorporate model hydrophobic dyes in their micelle-like structure. Two types of hydrogels were investigated. The first type was based on cationized dextran cross-linked by sodium dodecylsulphate. The second type was prepared by interactions of hyaluronan with carbethoxypendecinium bromide (septonex). Nile red and Atto488 were used as model dyes for the diffusion experiments. The dyes were dissolved in two different media: surfactant and physiological saline. The diffusion of dyes into hydrogel was monitored over time. Effective diffusion coefficients were determined. It was found that their values are strongly influenced by the hydrogel character, the types of dye used and the solvent. The obtained effective coefficients were higher in comparison with the values determined for the diffusion in the opposite direction (release from the hydrogel). The dyes are presented as free in physiological saline and in the form of micelles or micelle aggregates in surfactants. During diffusion into the hydrogel, they can be gradually incorporated in a “pearl necklace structure” which suppresses their mobility. In contrast, this partial immobilization of dyes can increase the concentration gradient which is a driving force of diffusion. Also, the gradual incorporation of dyes into hydrogel structures influences the values of the effective diffusion coefficients. Nilská červeň a Atto 488 byly použity jako modelová barviva pro studium transportních vlastnosttí hydrogelů připravených na bázi polyelektrolytů a opačně nabitých tenzidů. Jako polyelektrolyty byly použity kationizovaný dextran a hyaluronan dvou různých molárních hmotností. Opačně nabitými tenzidy byly SDS v případě dextranu a Septonex v případě obou hyaluronanů.

Silica sorbent samples were synthesized at different temperatures using saponins as surfactants in an acidic medium. The textural properties of the sorbent samples were studied by adsorbing benzene vapor onto them. The specific surface area of the sorbents at different temperatures was found to be 854,2 m2/g, while the pore volume ranged from 0,32 to 0,90 cm3/g. The average diameter of the pores was found to be in the range of 0,8-32,1 nm.

Mesoporous silica sorbent samples ordered at 30÷80°С were synthesized using the surfactant rutin using sol-gel technology. Based on the sorption of benzene vapors on sorbents, their texture and sorption properties were studied. According to it, it was determined that the specific surface area (SBET) of the sorbents is 675,6÷514,5 m2/g, and the average diameter of the pores is equal to 5,3÷32,8 nm.

Effects of sodium caseinate (SC) and its combination with OSA-modified starch (SC-OS; 1:1) alone and with n-alkyl gallates (C0-C18) on the physical and oxidative stability of high-fat fish oil-in-water emulsion were evaluated. SC emulsion contained the smallest droplets and highest viscosity due to the fast adsorption at droplet surfaces. Both emulsions had non-Newtonian and shear-thinning behavior. A lower accumulation of lipid hydroperoxides and volatile compounds was found in SC emulsion due to its better Fe2+ chelating activity. The incorporated short-chain gallates (G1 > G0∼G3) in SC emulsion had a strong synergistic effect against lipid oxidation compared to that of SC-OS emulsion. The better antioxidant efficiency of G1 can be related to its higher partition at the oil-water interface, while G0 and G3 had a higher partition into the aqueous phase. In contrast, G8, G12, and G16 added emulsions indicated higher lipid oxidation due to their internalization inside the oil droplets.

Bronchopulmonary dysplasia has been characterized as a chronic lung disease producing oxygen dependence of variable degree, as a result of a predominance of pulmonary injury factors that have had a higher incidence in premature newborns who have required mechanical ventilation and supplemental oxygen added to this prenatal and postnatal factor. Objective: To review scientific literature on neonatal bronchopulmonary dysplasia associated with prolonged mechanical ventilation. Methodology: In order to obtain relevant information to contribute to knowledge, a systematic review of original articles will be carried out including the databases Pubmed, Scopus, Scielo, using the following keywords "bronchopulmonary dysplasia, mechanical ventilation, surfactant oxygen therapy, caffeine, corticosteroids". We searched for articles written in Spanish, English, and Portuguese, published in the last 10 years. Results: A search was carried out in the following databases: Pubmed, Scopus, Scielo, in which we obtained a total of 638 documents, of which 588 did not meet the inclusion and exclusion criteria, so that for the present research we used 25 articles that met the inclusion and exclusion criteria and were those that responded to the objectives set. Conclusions: Despite several studies carried out since the first description of this disease, to date it has not been possible to eliminate the prevalence of this disease in neonates subjected to mechanical ventilation since this is an important clinical social and economic problem. In turn, it was concluded that, when using noninvasive ventilation, early use of surfactant and rapid extubating, as well as implementing strategies that regulate ventilatory parameters to avoid volutrauma are protective measures against lung injury.

The use of constructed wetlands (CWs) is a promising approach for the remediation of hydrocarbon-polluted wastewater. The amendments of CWs with nutrients, surfactants, and aeration enhances the removal of pollutants from wastewater. The objective of the present study was to explore the effect of external stimulants, i.e., nutrients, surfactant, and aeration on hydrocarbons degradation potential of CWs. The CWs mesocosms were developed by the vegetation of Phragmites australis and amendments with nutrients (20 mg l−1 N, 2.6 mg l−1 P, and 16.4 mg l−1 K), surfactant Tween 20 (0.2%, v/v), and aeration (7 mg l−1) for the remediation of diesel-spiked water (2%, w/v). The comparative analysis showed that the addition of nutrients, surfactant, and aeration individually enhanced total petroleum hydrocarbons (TPHs) reduction, and maximum TPHs reduction (88.4%) was achieved after 60 days in the mesocosms amended with the combination of nutrients, surfactant, and aeration. Among different individual treatments, the aeration (alone) also played a pivotal role in TPHs reduction (61%). The least (12%) reduction in TPHs was achieved in the mesocosms supplied with surfactant only. This study revealed that the combined application of nutrients, surfactant, and aeration in CWs enhanced its hydrocarbons degradation performance.

Surfactant is the standard therapy for respiratory distress syndrome (RDS) in preterm infants. Administration via a thin catheter is an alternative to surfactant after endotracheal intubation; however, the benefits remain unclear.

International audience; Most lipids in our diet come under the form of triacylglycerols that are often redispersed and stabilized by surfactants in processed foods. In plant however, lipid assemblies constitute interesting sources of natural bioactive and functional ingredients. In most photosynthetic sources, polar lipids rich in ω3 fatty acids are concentrated. The objective of this review is to summarize all the knowledge about the physico-chemical composition, digestive behavior and oxidative stability of plant polar lipid assemblies to emphasize their potential as functional ingredients in human diet and their potentialities to substitute artificial surfactants/antioxidants. The specific composition of plant membrane assemblies is detailed, including plasma membranes, oil bodies, and chloroplast; emphasizing its concentration in phospholipids, galactolipids, peculiar proteins, and phenolic compounds. These molecular species are hydrolyzed by specific digestive enzymes in the human gastrointestinal tract and reduced the hydrolysis of triacylglycerols and their subsequent absorption. Galactolipids specifically can activate ileal break and intrinsically present an antioxidant (AO) activity and metal chelating activity. In addition, their natural association with phenolic compounds and their physical state (Lα state of digalactosyldiacylglycerols) in membrane assemblies can enhance their stability to oxidation. All these elements make plant membrane molecules and assemblies very promising components with a wide range of potential applications to vectorize ω3 polyunsaturated fatty acids, and equilibrate human diet.

Ameliorating the problem of low leaching efficiency, long leaching period, and high agent consumption should be studied to efficiently exploit ion-absorbed rare earth ore resources. In this study, the surfactant sodium dodecyl sulfate (SDS) is used to enhance the leaching effect of an ion-absorbed rare earth ore by ameliorating the seepage effect for the first time. The effects of surfactant concentration, leaching agent dosage, solution flow velocity, and solution pH on the leaching rate were explored, and the mechanism of SDS was discussed. Under the optimum conditions, the addition of a small amount of SDS (mass fraction 0.04%) can increase the leaching rate by about 5%, shorten the leaching period, and reduce the consumption of the leaching agent. SDS significantly ameliorates the seepage effect of the ore body by reducing the surface tension of the leaching agent and ameliorating the wettability of the mineral surface. This effect is the main factor that improves the leaching efficiency. DFT (density functional theory) calculation results show that SDS can react with rare earth ions, which reduces the adsorption strength on clay mineral surfaces. Hence, rare earth ions are easily exchanged by ammonium ions, and mass transfer is enhanced.

In this present study, Rosmarinus officinalis essential oil and its new microemulsions (MEs) were evaluated both for the in vitro antibacterial and antifungal activity. The essential oil composition was verified initially both by GC-FID and GC/MS, where camphor (19.5%), 1,8-cineol (12%), and verbenone (11.1%) were characterized as the main constituents. A titration method was used and utilized to formulate the MEs. The preparation was formulated using isopropyl myristate as an oil phase, where sorbitan monolaurate and macrogol-glycerol ricinoleate were used as surfactants. In the same system, ethanol was utilized as co-surfactant and distilled water as aqueous phase. A total of 0.1% (w/w) of R. officinalis essential oil was dissolved within the formulation, and evaluated for characteristic parameters such as viscosity, pH, electrical conductivity, refractive index, polydispersity index (PDI), droplet size, and zeta potential, respectively. The pH value was 6.2, where the average microemulsion droplet size was 4.58 +/- 0.137 nm; the PDI value was found as 0.219 +/- 0.016. The viscosity of the microemulsion was determined as 6.93 +/- 0.015 cP. The conductivity of MEs was found as 10 mu S/cm; finally, the zeta potential was determined as 0.391 +/- 0.012 mV. The antimicrobial potential of the preparations was compared using the in vitro broth microdilution, and poisoned PDA assay. A significant increase in the anti-Candidal activity of the micro-emulsified essential oil (15.6 mu g/ml) was observed, however, the antibacterial susceptibility was rather low at the tested concentrations. In addition, the novel microemulsion preparation significantly inhibited mycelial growth of the plant pathogens used in the study, suggesting its selective antifungal potential.

Low-density polyethylene is the most applied packaging plastic. The recycling rate of LDPE is low, especially for the material from the post-consumer source. The quality of the LDPE post-consumer recyclates is influenced by different contaminations, either intentionally or non-intentionally. Printing ink is one of the substances that is regarded as having a negative influence on the quality of LDPE recyclates. This study used a new type of nonionic surfactant oxirane, methyl-, polymer for de-inking as a pretreatment. Afterward, the LDPE film flakes were mechanically recycled in the laboratory. A melt flow index (MFI), differential scanning calorimetry (DSC), and tensile strength analysis were carried out. This work reported the de-inking effect of a new type of nonionic surfactant. However, no evidential correlation between the rate of color removal and the improvement in the rheological, thermal, and mechanical properties can be identified from the result of this study. Low-density polyethylene is the most applied packaging plastic. The recycling rate of LDPE is low, especially for the material from the post-consumer source. The quality of the LDPE post-consumer recyclates is influenced by different contaminations, either intentionally or non-intentionally. Printing ink is one of the substances that is regarded as having a negative influence on the quality of LDPE recyclates. This study used a new type of nonionic surfactant oxirane, methyl-, polymer for de-inking as a pretreatment. Afterward, the LDPE film flakes were mechanically recycled in the laboratory. A melt flow index (MFI), differential scanning calorimetry (DSC), and tensile strength analysis were carried out. This work reported the de-inking effect of a new type of nonionic surfactant. However, no evidential correlation between the rate of color removal and the improvement in the rheological, thermal, and mechanical properties can be identified from the result of this study.

usc The potential exposure to the widely used glyphosate-based herbicides, including attempted suicide by ingestion, is of world-wide concern. Whilst the major focus to date has been on managing exposure to the active ingredient glyphosate, it is now recognised that a common major ‘inert’ surfactant ingredient, polyethoxylated tallow amine (POEA) and related compounds, may be more toxic. However, the information on the toxicokinetics of POEA surfactants after exposure is limited, in part, due to the lack of suitable methods for their analysis in biological matrices. We therefore developed and validated a robust LC-MSMS method that allowed, for the first time, a rapid analysis of 11 POEA homologues in human plasma. Chromatographic separation was achieved on a Kinetex EVO C18 column under a 5 min gradient elution with mobile phase A containing water/acetonitrile/formic acid (95:5:0.1, v/v/v) and mobile phase B containing acetonitrile/water/formic acid (95:5:0.1, v/v/v). Amlodipine was chosen as the internal standard (IS) for this assay. Amlodipine-d4 would be an ideal alternative IS to expand the applicability of the established method especially in antihypertensive patients. Multiple reaction monitoring (MRM) methods were optimized for 11 POEA homologues and the IS. Sample pre-treatment was performed using simple protein precipitation with methanol at a ratio of 4:1, requiring only 20 μL plasma. The validated method showed good specificity, accuracy and precision with lower limits of quantification (LLOQ) ranging from 0.35 to 10.8 ng mL−¹ for all selected POEA homologues. The method was then used to measure concentrations of the various POEA surfactants in more than 600 human plasma samples from 151 patients admitted to hospital with acute glyphosate intoxication. The highest concentrations ranged from 1.07 ng mL−¹ for C₁₈u(EO)₄–362.70 ng mL−¹ for C₁₆s(EO)₂. The analysis of POEA surfactants plasma concentrations as described here underpins the assessment of POEA internal exposure and the relationships between POEA related glyphosate toxicity and the extent of poisoning. Refereed/Peer-reviewed

In this study, we report on the developing of a continuous microfluidic reaction device that allows selective activation of polyelectrolyte-surfactant chemical signals in microflows and switches them between multiple outputs. A numerical model was developed for convection-diffusion reaction processes in reactive polymer-colloid microfluidic flows. Matlab scripts and scaling laws were developed for this model to predict reaction initiation and completion conditions in microfluidic devices and the location of the reaction front. The model allows the optimization of microfluidic device geometry and the setting of operation modes that provide release of the reaction product through specific outputs. Representing a chemical signal, polyelectrolyte-surfactant reaction products create various logic gate states at microfluidic chip outputs. Such systems may have potential as biochemical signal transmitters in organ-on-chip applications or chemical logic gates in cascaded microfluidic devices.

Refereed/Peer-reviewed The effect of hydrophilic/lipophilic balance (HLB) of polyoxyethylene ethers of different chain lengths on the microporogenic properties of the Brij surfactants has been studied. The objective of this work is to help better understand the role of each porogen and to set criteria for selecting the proper non-ionic surfactant, based on the HLB value. Seven recipes of different porogen compositions were first prepared and the highest efficiency was achieved using decane/decanol/dodecanol mixture with Brij® 30. Then, four other Brij surfactants covering the entire HLB scale were tested, and the prepared monoliths were characterized by SEM, BET, FT-IR and chromatography. The results showed that increasing the HLB from 9.72 to 18.84 was accompanied by an increase in monolith density and surface areas. The optimum HLB range was found to be 10 to 15. Surfactants of lower HLB formed either nonporous or less efficient columns, while those of higher HLB formed non-permeable columns. Adjusting the HLB was possible by mixing surfactants of different HLB. The prepared monoliths could be used in the isocratic mode with a mobile phase consisting of a mixture of ACN and water (20:80, v/v) at a flow rate of 1.5 μL min−1 to separate five sulfa drugs. The separation results showed that the elution order of the compounds correlated with their lipophilicity, with sulfamerazine (logp = 0.52) being the first to elute, and sulfaquinoxoline (logp=1.70) being the most retained. The asymmetry factors of the separated compounds ranged between 1.18 and 1.25, and the resolution was found to be in the range 2.92−7.80. The prepared monoliths could be also successfully separate a mixture of four different nonsteroidal anti-inflammatory drugs and a mixture of four benzoic acid derivatives. This work assists in optimizing the surfactant-based porogenic mixture to meet the desired porosity, surface area, morphology and chromatographic separation requirements.

The lipopeptide SPH6 isolated from the bacterial strain Pseudomonas H6 has surfactant properties and shows a lethal effect on all external stages of the problematic gill parasitic ciliate Ichthyopthirius multifiliis. The mode of action has remained enigmatic, but in the present study we have elucidated the mechanisms. I. multifiliis tomonts were exposed to a range of SPH6 concentrations (from 2.5 to 160 µg/mL), until the total motility inhibition of cells, cytoplasm and cilia. The parasites were subsequently examined by histology, light and scanning electron microscopy and enzyme activity assays (19 enzymes). The surfactant did not interfere with enzyme reactivity at any concentration, but at SPH6 concentrations 40 µg/mL and above the parasite cells became de-ciliated. Perforations were observed in the plasma membrane, and their origin and function may be associated with surfactant damage of the cell membrane or areas for extrusome release. Additional killing mechanisms may be involved, because lower concentrations were lethal as well, although the effect on density of cilia was not as pronounced. The study suggests that one mode of action mechanism is the surfactant attachment to and penetration of the parasite plasma membrane followed by detachment of cilia.

Molecular surfactants, which are based on a water-insoluble tail and a water-soluble head, are widely employed in many areas, such as surface coatings or for drug delivery, thanks to their capability to form micelles in solution or supramolecular structures at the solid/liquid interface. Electrolyte-gated organic field-effect transistors (EGOFETs) are highly sensitive to changes occurring at their electrolyte/gate electrode and electrolyte/organic semiconductor interfaces, and hence, they have been much explored in biosensing due to their inherent amplification properties. Here, we demonstrate that the EGOFETs and surfactants can provide mutual benefits to each other. EGOFETs can be a simple and complementary tool to study the aggregation behavior of cationic and anionic surfactants at low concentrations on a polarized metal surface. In this way, we have monitored the monolayer formation of cationic and anionic surfactants at the water/electrode interface with p-type and n-type devices, respectively. On the other hand, the operational stability of EGOFETs has been dramatically enhanced, thanks to the formation of a protective layer on top of the organic semiconductor by exposing it to a high concentration of a surfactant solution (above the critical micelle concentration). Stable performances were achieved for more than 10 and 2 h of continuous operation for p-type and n-type devices, respectively. Accordingly, this work points not only that EGOFETs can be applied to a wider range of applications beyond biosensing but also that these devices can effectively improve their long-term stability by simply treating them with a suitable surfactant., This work was funded by DGI (Spain) through project GENESIS PID2019-111682RB-I00, the Generalitat de Catalunya (2017-SGR-918), and the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centers of Excellence in R&D (FUNFUTURE CEX2019- 000917-S). A.T. acknowledges the FPU fellowship and is enrolled in the UAB Materials Science PhD program. F.L. gratefully acknowledges the “Juan de la Cierva” programme.

Objectives: Gene therapy approaches have become increasingly attractive in the medical, pharmaceutical, and biotechnological industries due to their applicability in the treatment of diseases with no effective conventional therapy. Non-viral delivery using cationic solid lipid nanoparticles (cSLNs) can be useful to introduce large nucleic acids to target cells. A careful selection of components and their amounts is critical to obtain a successful delivery system. In this study, solid Witepsol nanoparticles were formulated, characterized, and evaluated in vitro for gene delivery purposes. Materials and Methods: Solid Witepsol nanoparticles were formulated through the microemulsion dilution technique using two grades of Witepsol and three surfactants, namely Cremephor RH40, Kolliphor HS15, and Peceol. Dimethyldioctadecylammonium bromide was incorporated into the system as a cationic lipid. Twelve combinations of these ingredients were formulated. The obtained nanoparticles were then evaluated for particle size, zeta potential, DNA binding and protection ability, cytotoxicity, and transfection ability. Results: Particle sizes of the prepared cationic cSLNs were between 13.43 +/- 0.06 and 68.80 +/- 0.78 nm. Their zeta potential, which is important for DNA binding efficiency, was determined at >+40 mV. Gel retardation assays revealed that the obtained cSLNs can form a compact complex with plasmid DNA (pDNA) encoding green fluorescent protein and that this complex can protect pDNA from DNase I-mediated degradation. Cytotoxicity evaluation of nanoparticles was performed on the L929 cell line. In vitro transfection data revealed that solid Witepsol nanoparticles could effectively transfect fibroblasts. Conclusion: Our findings indicate that solid Witepsol nanoparticles prepared using the microemulsion dilution technique are promising non-viral delivery systems for gene therapy., Scientific and Technological Research Council of Turkey (TUBITAK) [218S840]; Izmir Katip Celebi University Research Fund [2020-ODL-ECZF-0001], This study has been financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under grant code 218S840 and Izmir Katip Celebi University Research Fund under grant code 2020-ODL-ECZF-0001. This paper is dedicated to the memory of our co-author dear Selen Isar, who sadly passed away on Wednesday, December 9th, 2020.

Made available in DSpace on 2021-06-25T11:13:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-06-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) In this study, NiFe2O4 nanoparticles (NPs) were prepared using the polymeric precursor method and calcined at 500°C for 4 h with (S– NiFe2O4) and without (NiFe2O4) CTAB as a surfactant, respectively. The magnetic and biological properties were evaluated based on the (micro)structure and electronic structure of the NPs. On sample S–NiFe2O4, the significant increase in magnetization saturation (Ms ~ 61.84 emu/g), magnetic remanence (Mr ~ 4.30 emu/g), and coercivity (Hc ~ 0.475 kOe) in comparison to sample NiFe2O4 (Ms ~ 24.81 emu/g, Mr ~ 1.00 emu/g, and Hc ~ 0.475 kOe) at room temperature (300 K) may be associated with the presence of oxygen vacancies the spinel lattice of NiFe2O4, generating magnetic moments. The concentration of 1 μg/mL S–NiFe2O4 decreased in ~50% angiogenesis in the chorioallantoic membrane (CAM). S–NiFe2O4 NPs showed high blood vessel affinity and anti-angiogenic activity; hence, effectively concentrating on tumoral vessels, which may enhance drug effectivity and enable simultaneous treatments, image diagnosis of solid tumors, etc. Thus, our results suggest that CTAB addition is an effective way to tune its magnetic response due to its excellent biocompatibility, high bulk saturation magnetization, and low magnetic anisotropy. São Paulo State University (UNESP) School of Engineering of Guaratinguetá Federal University of Itajubá (UNIFEI) Institute of Physical and Chemistry, Av. BPS, 1303 São Paulo State University (UNESP) School of Engineering of Guaratinguetá FAPESP: 2013/07296-2 CNPq: 573636/2008-7

Homologous series are groups of related compounds that share the same core structure attached to a motif that repeats to different degrees. Compounds forming homologous series are of interest in multiple domains, including natural products, environmental chemistry, and drug design. However, many homologous compounds remain unannotated as such in compound datasets, which poses obstacles to understanding chemical diversity and their analytical identification via database matching. To overcome these challenges, an algorithm to detect homologous series within compound datasets was developed and implemented using the RDKit. The algorithm takes a list of molecules as SMILES strings and a monomer (i.e., repeating unit) encoded as SMARTS as its main inputs. In an iterative process, substructure matching of repeating units, molecule fragmentation, and core detection lead to homologous series classification through grouping of identical cores. Three open compound datasets from environmental chemistry (NORMAN Suspect List Exchange, NORMAN-SLE), exposomics (PubChemLite for Exposomics), and natural products (the COlleCtion of Open NatUral producTs, COCONUT) were subject to homologous series classification using the algorithm. Over 2000, 12000, and 5000 series with CH2 repeating units were classified in the NORMAN-SLE, PubChemLite, and COCONUT respectively. Validation of classified series was performed using published homologous series and structure categories, including a comparison with a similar existing method for categorising PFAS compounds. The OngLai algorithm and its implementation for classifying homologues are openly available at: https://github.com/adelenelai/onglai-classify-homologues.

A recent trend in micro EDM is the addition of powders into the dielectric. The presence of powders helps to lower the dielectric breakdown voltage and therefore the discharge occurs early. As a result, the discharge energy is better distributed, resulting in a greater number of discharges, each with less energy. The main advantage of using this method is the improvement of both the process performance and surface finishing of the workpiece. A critical aspect of the implementation of this technology is in general the management of the powder. In fact, to obtain advantages during the machining, the powders should be maintained dispersed into the dielectric to avoid their aggregation. This paper aims to study the concentration of the powder and the surfactant in the dielectric fluid on micro EDM drilling performance. Titanium alloy was used as workpiece material, hydrocarbon oil as dielectric, graphite as powder and 4-dodecylbenzenesulfonic acid as surfactant. The performance was evaluated considering the Material Removal Rate, the Tool Wear Ratio and the geometrical characteristics of the holes (overcut and taper rate). Graphite content positively affected both Material Removal Rate and Tool Wear Ratio; a larger spark gap was observed as well. The use of surfactant is required for mix stability but increasing its percentage generally reduces the effects of graphite and increases data dispersion as well.

Nanoakışkanlar metal işleme sektöründe, işleme performansına son derece olumlu katkılar sunmaktadır. Son yıllarda özellikle nanoakışkanlar üzerine çalışmalar yoğunlaşmakla birlikte raf ömrü ve homojenliği bir merak konusudur. Homojen bir nanoakışkan elde etme ve karışımın raf ömrünü artırma adına farklı yüzey aktif maddeler (surfaktanlar) karışıma eklenebilmektedir. Bu çalışmada, CuO nanopartikül katkılı bitkisel esaslı yağın içerisine farklı oranlarda cetiltrimetilamonyum bromid (CTAB), polivinilpolipirolidon (PVP) ve sodyum dodesil sülfat (SDS) eklenerek nanoakışkan karışımlar hazırlanmıştır. Aynı oranlarda eklenen surfaktanların işleme performansı üzerindeki etkilerinin belirlenmesi adına AISI 329 dubleks paslanmaz çelik malzemeye bir dizi frezeleme deneyi uygulanmıştır. Deneyler Taguchi L9 deney seti kullanılarak gerçekleştirilmiştir. Deneylerde girdi parametresi olarak üç farklı surfaktan (CTAB, PVP ve SDS), kesme hızı (120, 160 ve 200 m/dak), ilerleme (0.10-0.15 ve 0.20 mm/dev) seçilmiştir. Performans kriteri olarak yüzey pürüzlülüğü (Ra), kesme sıcaklığı (T) ve takım aşınması tercih edilmiştir. Faktörlere ait etki düzeylerinin belirlenmesinde varyans analizi (ANOVA) kullanılmıştır. Deneylerden elde edilen sonuçlara göre; PVP surfaktan katkılı CuO nanoakışkanın Ra, kesme sıcaklığı ve takım aşınmasında en iyi performansı gösterdiği anlaşılmıştır., Nanofluids offer extremely positive contributions to the machining performance in the metalworking industry. Although studies on nanofluids have been intensified in recent years, shelf-life and homogeneity are a matter of curiosity. Different surface agents (surfactants) can be added to the mixture in order to obtain a homogeneous nanofluid and increase the shelf-life of the mixture. In this study, nanofluid mixtures were prepared by adding cethyltrimethylammonium bromide (CTAB), polyvinylpolypyrrolidone (PVP) and sodium dodecyl sulphate (SDS) at different rates into CuO nanoparticle added vegetable based oil. A series of milling experiments were applied to AISI 329 duplex stainless steel material to determine the effects of surfactants added in the same proportions on the machining performance. Experiments were carried out using the Taguchi L9 experimental set. Three different surfactants (CTAB, PVP, and SDS), cutting speed (120, 160, and 200 m/min), feed (0.10, 0.15, and 0.20 mm/rev) were selected as input parameters in the experiments. Surface roughness (Ra), cutting temperature (T) and tool wear were preferred as machining performance criteria. Analysis of variance (ANOVA) was used to determine the effect levels of the factors. According to the results obtained from the experiments; it was determined that PVP surfactant-added CuO nanofluid showed best performance in surface quality, cutting temperature and tool wear according to other surfactants.

Bubble dynamics plays a significant role in a wide range of industrial fields, such as food, pharmacy and chemical engineering. The physicochemical properties of complex fluids can greatly affect the speed with which bubbles rise, and the lifetime of bubbles, which in turn can affect the efficiency of food and drug manufacturing and also sewage purification. Therefore, it is of great scientific and practical significance to study the influence mechanism of nanoparticles and surfactants on bubble rising and impact in a complex fluid interface. This paper selects a mixed dispersion liquid of nanoparticles (SiO2) and a surfactant (SDS) as the objects of the study, observes in real-time the entire processes of bubbles rising, impact at the gas-liquid interface, and rupture, and analyzes the dynamic mechanism of bubble impact in a complex fluid interface. By analyzing the morphological changes of the rising bubbles, the rising velocity and the lifetime of the bubbles, it is found that the surfactant molecules are distributed in the ultrapure water liquid pool and the liquid film surrounding the bubbles. Such distribution can reduce the viscoelasticity between bubbles and the liquid surface, and lower the surface tension of the liquid, which can reduce the rising velocity of bubbles, delay the drainage process of bubbles on a liquid surface, and enhance the lifetime of bubbles. If the liquid surface is covered with nanoparticles, a reticulate structure will be formed on the bubble liquid film, which can inhibit bubble discharge and prolong bubble lifetime. In addition, the influence of such a reticulate structure on liquid surface tension is limited and its function is far smaller than a surfactant.

Foams are produced and stabilized in the presence of surface-active compounds such as surfactants and enzymes. The unavailability of significant research on enzyme foam generation and stability in industrial processes motivated this study whose objective is to investigate the potential of an enzyme to generate and stabilise foam under different conditions of temperature, salinity, pH and enzyme concentration. The residual foam height ratio (R5) method was used to analyse the foam stability under these conditions. The result of the study showed that the enzyme used in this study has the capacity to generate and stabilise foam, but the condition under which the foam is generated however influences its stability. Also, the foam stability depends on enzyme concentration, and it increases with increase in enzyme concentration. Increase in temperature however had an inverse effect on foam stability as it reduced its stability. Furthermore, a decrease in foam stability was observed with increase in brine salinity at all temperatures and enzyme concentrations. Finally, at high enzyme concentrations, increase in the pH of the solutions resulted in the production of very stable foams with R5 values greater than 70% for all temperatures investigated but at low enzyme concentration, the neutral solution (pH of 7) favoured the foam stability. This study presents the novel insight on enzymatic foam stability in salinity and temperature relevant to hydrocarbon reservoir.

Although plastics have benefited our lives in terms of cost and convenience, the disposal of end-of-life plastics poses environmental problems, such as microplastics (MPs). Although the separation (e.g., filtration) and staining of MPs with fluorescent dye/solvent are generally accepted steps to observe MPs in an environmental matrix, in this study, an in situ selective fluorescent illumination of the MPs in water was attempted with the aid of surfactant. Nonpolar fluorescent dye in combination with surfactant affords nanometer-sized dye particles in water, which adsorb on MPs and penetrate the polymer matrix for effective staining and stable fluorescent behaviors. The effects of different staining parameters, including different dyes, surfactants, staining temperatures, staining times, dye/surfactant ratios, dye/MP ratios, and MP concentrations in aqueous solutions were investigated to better understand staining conditions. More interestingly, non-adsorbed free dye molecules in the staining solution were almost completely fluorescence-quenched by introducing the quenching agent, aniline, while the fluorescence intensity of the stained MP was maintained. By staining MPs with a dye/surfactant combination and subsequently quenching with aniline, in situ selective fluorescent illumination of the MPs in water was successfully achieved, which may eliminate the tedious separation/filtration procedure of MPs to accomplish the quick detection or monitoring of MPs.

Aim:To determine the efficacy of three natural surfactant preparations in our community and the short- and long-term results of these on preterm infants.Materials and Methods:This was a retrospective research on 193 premature babies with respiratory distress syndrome (RDS). The patients were divided into three groups, each of which received one of three surfactants: Group 1; beractant (100 mg/kg); group 2; poractant alfa (first dose of 200 mg/kg, recurrent doses of 100 mg/kg); group 3; calfactant (100 mg/kg). The groups were compared according to demographic characteristics, 1- and 5-minute Apgar scores, weight percentiles by gestational week, presence of pulmonary hemorrhage, surfactant dose repetition, air leak, bronchopulmonary dysplasia (BPD), stage of intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), hemodynamically significant-patent ductus arteriosus (hs-PDA) and its medical or surgical treatment, retinopathy of premature (ROP) and its treatment, sepsis, ventilation time (both non-invasive and invasive), free oxygen need time, time to start full enteral feeding, discharge time, and mortality.Results:A total of 193 preterm infants with a mean gestational age of 28.9±3.1 weeks and mean birth weight of 1,190.4±504.3 grams were included in this study. The neonates were allocated into three different groups randomly, namely group-1 (n=77), group-2 (n=59), and group-3 (n=57). There were no differences in the clinical and demographic features of the groups. The incidence of pulmonary hemorrhage, surfactant dose repetition, air leak, ventilation time for both non-invasive and invasive, free oxygen need time, hs-PDA and surgical treatment of PDA, BPD, NEC (≥stage II), IVH (>stage III), ROP, time to start full enteral feeding, and discharge time were similar between the study groups. The sepsis and mortality rates were lower in group 3 compared to groups 1 and 2 (p=0.015, p=0.001).Conclusion:In this study, beractant, proctant alfa and calfactant had clinically similar efficacy in patients with RDS.

Fetal growth restriction can affect health outcomes in postnatal life. This study tested the hypothesis that the response to an inflammatory pulmonary insult is altered in pediatric fetal growth restricted rats. Using a low-protein diet during gestation and postnatal life, growth-restricted male and female rats and healthy control rats were exposed to an inflammatory insult via the intratracheal instillation of heat-killed bacteria. After 6 h, animal lungs were examined for lung inflammation and status of the surfactant system. The results showed that in response to an inflammatory insult, neutrophil infiltration was decreased in both male and female rats in the growth-restricted animals compared with the control rats. The amount of surfactant was increased in the growth-restricted animals compared with the control rats, regardless of the inflammatory insult. It is concluded that fetal growth restriction results in increased surfactant and altered neutrophil responses following pulmonary insult.

This study aims to determine the effect of sea sand modification with SDBS for adsorption of Fe3+. Sea sand was treated with 0.1 M HCl solution at 25oC. Organo-quartz was prepared at SDBS concentration of below, equal, and above the CMC value by shaking the mixture for 4 hours at 100 rpm. Characterization by FTIR spectrophotometry showed a change in the spectra pattern. The activation caused increasing of -OH silanol while modifications make them decrease. Characterization with SEM showed that the morphology of the sea sand was not uniform with irregular white chunks. The EDX results showed that the dominant elements were C (13.89% ± 10.86), O (40.48% ± 6.58), Si (16.51% ± 8.13), and Fe (11.68% ± 14.38). Adsorption was carried out using Fe3+ at 50 ppm. The Fe3+ analysis was conducted by AAS. The adsorption value by activated sea sand was 58.22% ± 7.23% whereas without treatment sea sand was 70.46% ± 5.54, and the modified sea sand was 53.24% ± 4.86. The lower adsorption is probably caused by the dissolved iron oxides in sea sand during activation.

[EN] In this study, two different non-ionic surfactants have been evaluated as a plasticizer in lithium polymer electrolytes and compared with an organic carbonate-based plasticizer. To that end, non-ionic surfactants with different molecular weight and structure have been selected (Triton? X-100 and Brij?L23) and compared with organic carbonates (EC:DEC1:1) as plasticizers in lithium polymer electrolytes. The effect of the plasticizer content, salt content and surfactant characteristics on properties such as ionic conductivity, thermal stability and electrochemical stability of lithium polymer electrolytes has been studied. The results obtained show that the non-ionic surfactants studied as plasticizers (Triton? X-100 and Brij?L23) give lithium polymer electrolytes with higher thermal and electrochemical stability than organic carbonates, thus making them promising plasticizers for lithium polymer electrolytes, especially for high voltage lithium-ion batteries. Surfactant structure could influence the ionic conductivity of the polymer electrolytes, with the linear surfactants being more suitable for this application., This research was funded by the Centro de Desarrollo Tecnologico Industrial-CDTI (ALMAGRID Project-CER-20191006) and by the Instituto Valenciano de Competitividad EmpresarialIVACE-FEDER (MATER Project-IMDEEA/2019/48)

Grey water is a kind of domestic wastewater including shower, bath, lavatory and laundry waters. Grey waters without faecal waste can be considered as alternative water sources in the place where water resources are limited. In the present study, the removals of COD, anionic and non-ionic surfactants from grey water via conventional (CFP) and modified (MFP) Fenton oxidation processes was experienced. It was determined that pH adjustment to acidic values is not required in CFP. The optimum operating conditions were determined as [Fe2+] = 50 mg/L, [H2O2] = 50 mg/L at pH 7.6 (original pH) in CFP and [ZVI] = 50 mg/L, [H2O2] = 50 mg/L at pH 3 in MFP, respectively. As a result, the CFP has been found to be a more efficient alternative treatment method for the treatment of grey water, compared to MFP.