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Citric acid, a tricarboxylic acid, has found wide application in the chemical and pharmaceutical industry due to its biocompatibility, versatility, and green, environmentally friendly chemistry. This review emphasizes the pharmaceutical uses of citric acid as a strategic ingredient in drug formulation while focusing on the impact of its physicochemical properties. The functionality of citric acid is due to its three carboxylic groups and one hydroxyl group. These allow it to be used in many ways, including its ability to be used as a crosslinker to form biodegradable polymers and as a co-former in co-amorphous and co-crystal applications. This paper also analyzes the effect of citric acid in physiological processes and how this effect can be used to enhance the attributes of pharmaceutical preparations, as well as providing a critical discussion on the issues that may arise out of the presence of citric acid in formulations.

The seeds of dissected hogweed (Heracleum dissectum Ledeb., Apiaceae) are the source of hogweed oil (HSO), which is still underexplored and requires careful chemical and biological studies. The performed physico–chemical analysis of HSO elucidated basic physical characteristics and revealed the presence of fatty acids, essential oil components, pigments, and coumarins. High-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection (HPLC–PDA–ESI–tQ–MS/MS) identified 38 coumarins that were characterized and quantified. Various furanocoumarins were the major components of HSO polyphenolics, including imperatorin, phellopterin, and isoimperatorin, and the total coumarin content in HSO varied from 181.14 to 238.42 mg/mL. The analysis of storage stability of the selected compounds in HSO indicated their good preservation after 3-year storage at cold and freezing temperatures. The application of the CO2-assisted effervescence method allowed the production of an HSO nanosuspension, which was used in a brain ischemia model of rats. The HSO nanosuspension enhanced cerebral hemodynamics and decreased the frequency of necrotic processes in the brain tissue. Thus, H. dissectum seeds are a good source of coumarins, and HSO nanosuspension promotes neuroprotection of the brain after lesions, which supports earlier ethnopharmacological data.

Non-reciprocal interactions between scalar fields that represent the concentrations of two active species are known to break the parity and time-reversal (PT) symmetries of the equilibrium state, as manifested in the emergence of travelling waves. We explore the notion of nonlinear non-reciprocity and consider a model in which the non-reciprocal interactions can depend on the local values of the scalar fields in such a way that the non-reciprocity can change sign. For generic cases where such couplings exist, we observe the emergence of spatiotemporal chaos in the steady-state. We associate this chaotic behaviour with a local restoration of PT symmetry in fluctuating spatial domains, which leads to the coexistence of oscillating densities and phase-separated droplets that are spontaneously created and annihilated. We uncover that this phenomenon, which we denote as effervescence , can exist as a dynamical steady-state in large parts of the parameter space in two different incarnations, as characterised by the presence or absence of an accompanying travelling wave. Non-reciprocal interactions in active matter systems can lead to nontrivial types of collective behaviour. The authors describe the emergence of a dynamical state, termed effervescence, characterized by spatiotemporal chaos manifesting as a coexistence of unstable droplets and oscillating densities.

This study developed a new effervescence-assisted switchable fatty acid-based microextraction combined with solidification of a floating organic-droplet (EA-SFAM-SFO) for simple and rapid determination of fluoroquinolones and tetracyclines in seawater, sediment, and seafood. Five medium-chain fatty acids (pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, and nonanoic acid) were tested as an extraction solvent, given their ability to change between hydrophobic and hydrophilic forms by pH adjustment. As nonanoic acid had the highest extraction recovery (>92%) for the six antibiotics and the ability to transform from liquid to a solidified floating state at low temperature, it was selected as the optimum extraction solvent. The prominent advantages of the newly developed method are: (1) reaction between the procedures salt and fatty acid changed extraction solvent from the hydrophobic to hydrophilic state; (2) bubbling with CO2 greatly increased the contact area between fatty acid and analytes resulting in improved extraction recovery; and (3) solidification of the fatty acid at a low temperature provided good separation and avoided the use of specialized equipment. Single-factor screening and optimization of the main factors were conducted using Plackett-Burman design and central composite design, respectively. The main parameters were optimized as follows: 258 μL fatty acid, 406 μL H2SO4 (98%), 3.9 min vortex time, and 354 μL Na2CO3 (2 mol L-1). Under optimized conditions, limits of detection were 0.007–0.113 μg L-1 or μg kg-1 and extraction recoveries were 82.2%–116.7% for six fluoroquinolone and tetracycline antibiotics in seawater, sediments, and seafood. The newly developed method combines the advantages of effervescence-assisted dispersion, hydrophobic/hydrophilic switchable solvent, and liquid/solid transition induced by low temperature. Overall, the new method is simple, quick, and environment-friendly with low detection limits and high recoveries. Thus, the newly developed method has excellent prospects for sample pretreatment and analysis of antibiotics in marine environmental and food samples.

In 1799, Hatchett decalcified shells of crabs, lobsters, prawns and crayfish with mineral acids, observing that they produced a moderate effervescence and in a short time were found to be soft and plastic of a yellowish color and like a cartilage, which retained the original figure. Although this is the first mention of calcified chitin in invertebrates, the discovery of chitin is usually attributed both to Braconnot in 1811 who discovered chitin from fungi, and to Odier in 1823 who obtained a hornlike material after treatment of cockchafer elytra with potassium hydroxide. Chitin was first named fongine by Braconnot and then chitine by Odier. Children revealed the nitrogenous nature of chitin in 1824. The history of chitosan, the main derivative of chitin, dates back to 1859 with the work of Rouget. The name of chitosan was, however, introduced in 1894 by Hoppe-Seyler. In 1876, Ledderhose hydrolyzed arthropod chitin and discovered glykosamin, the first derivative of chitin. This review describes the 220 years of the development of chitin. I have roughly divided the story into five periods: discovery from 1799 to 1894, a period of confusion and controversy from 1894 to 1930, exploration in 1930–1950, a period of doubt from 1950 to 1970, and finally the period of application from 1970. The different periods are illustrated by examples of published studies, in particular from outstanding scholars who have left their mark on the history of this polysaccharide. Although this historic review is not exhaustive, it highlights the work of researchers who have contributed to the development of our knowledge of chitin throughout the 220 years of its history.

For the first time in this study, a sample preparation approach named self-effervescence-assisted dispersive micro-solid-phase extraction linked to dispersive liquid–liquid micro-extraction was evolved. This approach was applied to extract and preconcentrate some esteric compounds in plastic-bottled sparkling water samples. MIL-53 (Cr) was exploited as an adsorbent in the introduced method. In the procedure, releasing CO 2 gas molecules from the sample after the addition of the mixture of metal–organic framework and Na 2 SO 4 facilitated the sorption of analytes onto the sorbent. Vortexing was also implemented to increase extraction recoveries. After the sorption process, a mL level of 2-propanol was applied to desorb the target compounds. The obtained 2-propanol phase was then mixed with µL-level of 1,2-dibromoethane solvent as an extractant and injected into 5 mL of deionized water. Centrifugation of the formed milky solution induced sedimentation of 10 ± 0.5 µL of the organic phase containing the analytes. Injection of 1.0 µL of the stated phase into a gas chromatograph equipped with a flame ionization detector commenced the separation, detection, and determination of the analytes in the studied matrix. The obtained linear ranges in this survey were wide. Also, the linearities of the calibration curves drawn for the analytes were pleasant (r 2  ≥ 0.995). Moreover, reaching low limits of detection and quantification documented as 0.96–1.40 and 3.17–4.62 µg L −1 , respectively, were the highlights of the study. As the finding of the research, di(2-ethylhexyl) phthalate was detected and quantified as 33 ± 2 μg L −1 (n = 3) in the surveyed plastic-bottled sparkling water.

Collective rituals are present in all known societies, but their function is a matter of long-standing debates. Field observations suggest that they may enhance social cohesion and that their effects are not limited to those actively performing but affect the audience as well. Here we show physiological effects of synchronized arousal in a Spanish fire-walking ritual, between active participants and related spectators, but not participants and other members of the audience. We assessed arousal by heart rate dynamics and applied nonlinear mathematical analysis to heart rate data obtained from 38 participants. We compared synchronized arousal between fire-walkers and spectators. For this comparison, we used recurrence quantification analysis on individual data and cross-recurrence quantification analysis on pairs of participants' data. These methods identified fine-grained commonalities of arousal during the 30-min ritual between fire-walkers and related spectators but not unrelated spectators. This indicates that the mediating mechanism may be informational, because participants and related observers had very different bodily behavior. This study demonstrates that a collective ritual may evoke synchronized arousal over time between active participants and bystanders. It links field observations to a physiological basis and offers a unique approach for the quantification of social effects on human physiology during real-world interactions.

Abstract—The purpose of this work is to create a digital map of surface-effervescing soils based on space imagery and field research data; and to compare soil mapping procedure using remote and ground-based methods. The research was carried out at the Oroshaemaya experimental station (Volgograd Oblast) located in the south of the Volga Upland. The soil cover is represented by light-chestnut (Kastanozems) and solonetz microassociations on arable and irrigated lands. The article traces all stages of creating a digital map based on space images and field research in 2020–2023. Field studies included route work to assess the intensity (class) of effervescence with 10% HCl at the soil surface. Based on the relationship between the spectral characteristics of the open soil surface in high-resolution Pleiades satellite imagery (April 25, 2020) and the intensity of soil effervescence, the raster space images were classified into 4 classes separately for 26 fields using the Random Forest algorithm. The following layers were created from the raster: (1) vector layers of field boundaries with the calculation of the proportion of effervescent soils of different classes in the field; (2) vector layers of polygons inside the fields with different proportions of different classes. To vectorize the polygons of surface-effervescing soils, the QGIS program and functions were used. Estimates of the proportion of effervescing soils within the field obtained only by a ground survey and estimates based on a digital map created by vectorization of the raster classified by the Random Forest algorithm are comparable to each other with a determination coefficient of 0.68–0.83. A digital vector map of polygons, created using a model that links remote sensing data and ground-based sampling data, allows us to determine specific parameters of the soil cover pattern based on the presence of surface-effervescing soils and to assess the anthropogenic transformation of the soil cover using the previously proposed indicator.

Dispersive microextraction techniques are key in the analytical sample treatment context as they combine a favored thermodynamics and kinetics isolation of the target analytes from the sample matrix. The dispersion of the extractant in the form of tiny particles or drops, depending on the technique, into the sample enlarges the contact surface area between phases, thus enhancing the mass transference. This dispersion can be achieved by applying external energy sources, the use of chemicals, or the combination of both strategies. Effervescence-assisted microextraction emerged in 2011 as a new alternative in this context. The technique uses in situ-generated carbon dioxide as the disperser, and it has been successfully applied in the solid-phase and liquid-phase microextraction fields. This minireview explains the main fundamentals of the technique, its potential and the main developments reported.

Armies, churches, organizations, and communities often engage in activities--for example, marching, singing, and dancing--that lead group members to act in synchrony with each other. Anthropologists and sociologists have speculated that rituals involving synchronous activity may produce positive emotions that weaken the psychological boundaries between the self and the group. This article explores whether synchronous activity may serve as a partial solution to the free-rider problem facing groups that need to motivate their members to contribute toward the collective good. Across three experiments, people acting in synchrony with others cooperated more in subsequent group economic exercises, even in situations requiring personal sacrifice. Our results also showed that positive emotions need not be generated for synchrony to foster cooperation. In total, the results suggest that acting in synchrony with others can increase cooperation by strengthening social attachment among group members.