Hasil untuk "General. Including alchemy"

K. Merikangas, M. Stolar, D. Stevens et al.

Federica Torregrossa, Luciano Cinquanta, Francesca Mazza et al.

Mucilage extracted from cladodes of <i>Opuntia ficus-indica</i> (L.) Mill. has attracted growing interest as a natural food additive due to its gelling and nutritional properties. In this study, the chemical characteristics of <i>Opuntia ficus-indica</i> mucilage were comparatively evaluated against commercial pectin, with particular emphasis on volatile compounds, mineral composition, and monosaccharide profiles by ¹³C-NMR spectroscopic analysis. The volatile components were analysed using gas chromatography–mass spectrometry (GC-MS), revealing distinct aromatic profiles between the two matrices, with the mucilage showing a significant presence of methoxypyrazines, but not detected in the powdered pectin studied. These compounds could negatively affect the sensory perception of mucilage. Mineral analysis demonstrated significantly higher levels of calcium, magnesium, and potassium, supporting its potential contribution to nutritional enrichment. The spectroscopic analysis, used to identify monosaccharide composition of polysaccharide chains, highlighted the presence of arabinose, galactose, glucose, and rhamnose in the mucilage sample compared to the predominantly glucose/galacturonic acid-based structure of pectin. Overall, the results indicate that <i>Opuntia ficus-indica</i> mucilage represents a promising alternative to pectin, offering unique chemical properties that may expand its application as a multifunctional, natural food additive.

Raghvendra Pratap Singh, Kaushik Bhattacharjee, Alok R. Rai et al.

Ruping Chen, Hong He, Yuhang Tian et al.

The viscoelastic branched-preformed particle gel (B-PPG) has been successfully applied to enhance oil recovery in mature reservoirs. However, due to a lack of a clear understanding of the transport characteristics of B-PPG in porous media, the injectivity and plugging efficiency are not ideal, and the incremental oil recovery is not as expected, which poses a great obstacle to the large-scale popularization and application of B-PPG in mature oilfields. Thus, the influences of elastic moduli, matching coefficients, and injection rates on transport characteristics of B-PPG in porous media were investigated by conducting core flow experiments. The results indicate that the elastic modulus of B-PPG can significantly affect the injectivity and plugging efficiency. The higher the elastic modulus is, the more difficult it is to transport in the porous medium. When the particle size is similar, as the elastic modulus increases, the resistance factor (<i>F_r</i>) and residual resistance factor (<i>F_rr</i>) increase. When the elastic modulus is similar, as the particle size increases, the <i>F_r</i> and <i>F_rr</i> increase. As the matching coefficient decreases, the <i>F_r</i> and <i>F_rr</i> decrease, reflecting the improvement of injectivity and the weakening of plugging efficiency. The higher the reservoir permeability, the lower the matching coefficient. When the reservoir permeability ranges from 0.30 to 5.30 μm², the B-PPG with an elastic modulus of 42.2 Pa and a <i>D</i>₅₀ of 525 μm can migrate smoothly into the depth of porous media and form effective plugging. As the injection rate increases, the <i>F_r</i> and <i>F_rr</i> decrease, reflecting the improvement of injectivity and the weakening of plugging efficiency. Therefore, to achieve good injectivity and plugging efficiency of the B-PPG suspension, the injection rate should be in the range of 0.5 mL·min⁻¹ to 1.5 mL·min⁻¹. Hence, these findings could give an important understanding of the factors affecting the transport characteristics of B-PPG and provide guidance for enhancing oil recovery by B-PPG flooding in mature oilfields.

Teresa T. Duncan, Michelle R. Sullivan, Amy Elizabeth Hughes et al.

We present an exploration of an overlooked process in gel cleaning that promotes efficient cleaning of discoloration and stains from artworks on paper: adsorption. Agarose, in both solid and gelled forms, is an efficient adsorbent of crystal violet, which is used here as a marker to assess the capability of a system to immobilize solutes. Incorporating additional adsorbents, either 1% by mass microcellulose or silica gel, into the gel before casting greatly improves the efficiency of removing and retaining dye from water. This addition induces a slight (2×) increase in the elastic modulus but results in no impactful change in the handling properties for conservation practice. We show that the addition of silica gel increases the efficacy of removing water-soluble degradation products from a sheet of historic book paper. A case study of a water-damaged eighteenth-century print, with element maps collected using mapping µX-ray fluorescence analysis before and after gel cleaning, demonstrates that microcellulose-containing gels can be used to remove water-soluble salts from the print. This work provides a new methodology for tailoring gels to target specific conservation treatment outcomes. Specifically, efficient adsorption of solubilized material increases the efficacy of the gel cleaning and minimizes redeposition.

Amin Raeisi, Mohammad Doroudian, Banafsheh Rastegari et al.

A key obstacle to the efficacy of cancer drugs is the safe delivery of the drugs to the target site of the disease. Recent advances in nanomedicine have introduced smart hydrogel nanoparticles as promising, efficient, secure, and stimulus-responsive drug carriers. Herein, a bio-safe pH-sensitive nanohydrogel (NG) made of polyaminoethyl methacrylamide (AEMA)-grafted dextran was used as a carrier for liver-targeted doxorubicin (DOX) delivery. Lactobionate (SL) residue was conjugated to the prepared NG as a targeting agent, and DOX was also conjugated via Schiff base linkage. The synthesized structure was analyzed using ¹HNMR, FT-IR, and size exclusion chromatography. DOX release was confirmed through UV-Vis spectroscopy. A pH-responsive manner in the DOX release profile was observed in a simulated medium with pH changes. In vitro toxicity assessment was performed in HepG2 and L929 cell lines, which have demonstrated the biosafety of the prepared hydrogel and its high effectiveness as an anticancer drug delivery system.

Maria Rosaria Sellitto, Domenico Larobina, Chiara De Soricellis et al.

Infection control and bleeding management in deep wounds remain urgent and unmet clinical challenges that demand innovative, multifunctional, and sustainable solutions. Unlike previously reported sodium alginate and silk fibroin-based gel formulations, the present work introduces a dual-functional system combining antimicrobial and haemostatic activity in the form of conformable aerogel beads. This dual-functional formulation is designed to absorb exudate, promote clotting, and provide localized antimicrobial action, all essential for accelerating wound repair in high-risk scenarios within a single biocompatible system. Aerogel beads were obtained by supercritical drying of a silk fibroin–sodium alginate blend, resulting in highly porous, spherical structures measuring 3–4 mm in diameter. The formulations demonstrated efficient ciprofloxacin encapsulation (42.75–49.05%) and sustained drug release for up to 12 h. Fluid absorption reached up to four times their weight in simulated wound fluid and was accompanied by significantly enhanced blood clotting, outperforming a commercial haemostatic dressing. These findings highlight the potential of silk-based aerogel beads as a multifunctional wound healing platform that combines localized antimicrobial delivery, efficient fluid and exudate management, biodegradability, and superior haemostatic performance in a single formulation. This work also shows for the first time how the prilling encapsulation technique with supercritical drying is able to successfully produce silk fibroin and sodium alginate composite aerogel beads.

Samuel Koovely

We introduce a queueing-based sampling framework for continuous-time temporal networks. We focus on a Markovian parametrization in which link start times follow a homogeneous Poisson process and link durations are exponentially distributed. We derive stochastic properties of the resulting link streams and exploit them to generate synthetic temporal networks with controllable smoothness and prescribed event patterns, relevant for the validation and interpretation of methods for community, scale, change-point, and periodicity detection. By coupling this temporal mechanism with block-structured endpoint distributions, we obtain a continuous-time analogue of stochastic block models. We also discuss extensions of the framework, including discrete-time and instantaneous-contact limits.

Julia F. Strand, Violet A. Brown, Katrina Sewell et al.

It is common practice in speech research to only sample participants who self-report being "native English speakers." Although there is research on differences in language processing between native and nonnative listeners (see Lecumberri et al., 2010, for a review), the majority of speech research that aims to establish general findings (e.g., testing models of spoken word recognition) only includes native speakers in their sample. Not only is the "native English speaker" criterion poorly defined, but it also excludes historically underrepresented groups from speech perception research, often without attention to whether this exclusion is likely to affect study outcomes. The purpose of this study is to empirically test whether and how using different inclusion criteria ("native English speakers" vs. "nonnative English speakers") affects several well-known phenomena in speech perception research. Five hundred participants completed word (N = 200) and sentence (N = 300) identification tasks in quiet and in moderate levels of background noise. Results indicate that multiple classic findings in speech perception research-including the effects of noise level, lexical density, and semantic context on speech intelligibility-persist regardless of "native English" speaking status. However, the magnitude of some of these effects differed across participant groups. Taken together, these results suggest that researchers should carefully consider whether native speaker status is likely to affect outcomes and make decisions about inclusion criteria on a study-by-study basis. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Shengming Huang, Tengfei Dong, Guancheng Jiang et al.

Addressing the high friction and torque challenges encountered in drilling processes for high-displacement wells, horizontal wells, and directional wells, we successfully synthesized OAG, a high-temperature and high-salinity drilling fluid lubricant, using materials such as oleic acid and glycerol. OAG was characterized through Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). The research findings demonstrate the excellent lubricating performance of OAG under high-temperature and high-salinity conditions. After adding 1.0% OAG to a 4% freshwater-based slurry, the adhesion coefficient of the mud cake decreased to 0.0437, and at a dosage of 1.5%, the lubrication coefficient was 0.032, resulting in a reduction rate of 94.1% in the lubrication coefficient. After heating at 200 °C for 16 h, the reduction rate of the lubrication coefficient reached 93.6%. Even under 35% NaCl conditions, the reduction rate of the lubrication coefficient remained at 80.3%, indicating excellent lubrication retention performance. The lubricant OAG exhibits good compatibility with high-density drilling fluid gel systems, maintaining their rheological properties after heating at 200 °C and reducing filtration loss. The lubrication mechanism analysis indicates that OAG can effectively adsorb onto the surface of N80 steel sheets. The contact angle of the steel sheets increased from 41.9° to 83.3° before and after hot rolling, indicating a significant enhancement in hydrophobicity. This enhancement is primarily attributed to the formation of an extreme-pressure lubricating film through chemical reactions of OAG on the metal surface. Consequently, this film markedly reduces the friction between the drilling tools and the wellbore rocks, thereby enhancing lubrication performance and providing valuable guidance for constructing high-density water-based drilling fluid gel systems.

Patrick Micheels, Alexandre Porcello, Thierry Bezzola et al.

Dermal filler injectability is a critical factor for commercial product adoption by medical aesthetic professionals and for successful clinical administration. We have previously reported (in vitro and ex vivo) cross-linked hyaluronic acid (HA)-based dermal filler benchmarking in terms of manual and automated injectability requirements. To further enhance the function-oriented product characterization workflows and the clinical relevance of dermal filler injectability assessments, the aim of this study was to perform in vivo evaluations. Therefore, several variants of the MaiLi^® product range (OxiFree™ technology) were characterized in vitro and in vivo in terms of injectability attributes, with a focus on hydrogel system homogeneity and ease of injection. Firstly, standardized in vitro assays were performed in SimSkin^® cutaneous equivalents, with variations of the clinical injector, injection site, and injection technique. Then, automated injections in SimSkin^® cutaneous equivalents were comparatively performed in a texture analysis setup to obtain fine-granulometry injection force profile results. Finally, five female participants were recruited for the in vivo arm of the study (case reports), with variations of the clinical injector, injection site, and injection technique. Generally, the obtained quantitative force values and injection force profiles were critically appraised from a translational viewpoint, based on discussions around the OxiFree™ manufacturing technology and on in-use specialized clinician feedback. Overall, the present study outlined a notable level of homogeneity across the MaiLi^® product range in terms of injectability attributes, as well as consistently high ease of administration by medical aesthetic clinicians.

Min Bao, Nanase Harada, Kotaro Kohno et al.

The physical properties of galactic molecular outflows are important as they could constrain outflow formation mechanisms. We study the properties of the southwest (SW) outflow streamer including gas kinematics, optical depth, dense gas fraction, and shock strength in the central molecular zone of the starburst galaxy NGC 253. We image the molecular emission at a spatial resolution of $\sim$27 pc based on data from the ALCHEMI program. We trace the kinematics of molecular gas with CO(1-0) line. We constrain the optical depth of CO emission with CO/$^{13}$CO(1-0) ratio, the dense gas fraction with HCN/CO(1-0) ratio, as well as the shock strength with SiO(2-1)/$^{13}$CO(1-0) ratio. The CO/$^{13}$CO(1-0) integrated intensity ratio is $\sim$21 in the SW streamer region, which approximates the C/$^{13}$C isotopic abundance ratio. The higher integrated intensity ratio compared to the disk can be attributed to the optically thinner environment for CO(1-0) emission inside the SW streamer. The HCN/CO(1-0) and SiO(2-1)/$^{13}$CO(1-0) integrated intensity ratios both approach $\sim$0.2 in three giant molecular clouds (GMCs) at the base of the outflow streamers, which implies the higher dense gas fraction and enhanced strength of fast shocks in those GMCs than in the disk. The contours of those two integrated intensity ratios are extended towards the directions of outflow streamers, which connects the enhanced dense gas fraction and shock strength with molecular outflow. Moreover, the molecular gas with enhanced dense gas fraction and shock strength located at the base of the SW streamer shares the same velocity with the outflow. These phenomena suggest that the star formation inside the GMCs can trigger the shocks and further drive the molecular outflow.

Olga Chudinovych

The phase equilibria in the ternary La2О3–Lu2O3–Er2O3 system at 1250°C were studied by X-ray diffraction, and electron microscopy in the overall concentration range. At 1250°С in the La2О3–Lu2O3–Er2O3 system solution fields are formed based on cubic (C) modification of Lu2O3(Er2O3), hexagonal (A) modification of La2O3, as well as ordered phase structure perovskite-type LaLuO3 (LaErO3) (R). The isothermal section of the La2O3–Lu2O3–Er2O3 phase diagram at 1250°C has shown the three one-phase fields (A-La2O3, R, C-Lu2O3(Er2O3)) corresponding to solid solutions based on starting components and two dual-phase fields (C+R, A+R) between them. The refined lattice parameters of the unit cells for solid solutions and microstructures of the definite field of compositions for the systems solid were determined.

Murugiah Krishani, Wong Yen Shin, Hazwani Suhaimi et al.

Tissue damage and organ failure are major problems that many people face worldwide. Most of them benefit from treatment related to modern technology’s tissue regeneration process. Tissue engineering is one of the booming fields widely used to replace damaged tissue. Scaffold is a base material in which cells and growth factors are embedded to construct a substitute tissue. Various materials have been used to develop scaffolds. Bio-based natural materials are biocompatible, safe, and do not release toxic compounds during biodegradation. Therefore, it is highly recommendable to fabricate scaffolds using such materials. To date, there have been no singular materials that fulfill all the features of the scaffold. Hence, combining two or more materials is encouraged to obtain the desired characteristics. To design a reliable scaffold by combining different materials, there is a need to choose a good fabrication technique. In this review article, the bio-based natural materials and fine fabrication techniques that are currently used in developing scaffolds for tissue regeneration applications, along with the number of articles published on each material, are briefly discussed. It is envisaged to gain explicit knowledge of developing scaffolds from bio-based natural materials for tissue regeneration applications.

Gabriela Itziar Saavedra Isusi, Johannes Marburger, Nils Lohner et al.

Soy-based yoghurt alternatives were highly requested by consumers over the last few years. However, their texture does not always fulfil consumers’ demands as such yoghurt alternatives are often perceived as too firm or too soft, sandy, or fibrous. In order to improve the texture, fibres, for example, in the form of microgel particles (MGP), can be added to the soy matrix. MGP are expected to interact with soy proteins, creating different microstructures and, thus, different gel properties after fermentation. In this study, pectin-based MGP were added in different sizes and concentrations, and the soy gel properties after fermentation were characterised. It was found that the addition of 1 wt.% MGP influenced neither the flow behaviour nor the tribological/lubrication properties of the soy matrix, regardless of the MGP size. However, at higher MGP concentrations (3 and 5 wt.%), the viscosity and yield stress were reduced, the gel strength and cross-linking density decreased, and the water-holding capacity was reduced. At 5 wt.%, strong and visible phase separation occurred. Thus, it can be concluded that apple pectin-based MGP serve as inactive fillers in fermented soy protein matrices. They can, therefore, be used to weaken the gel matrix purposely to create novel microstructures.

Irina Negut, Bogdan Bita

AI and ML have emerged as transformative tools in various scientific domains, including hydrogel design. This work explores the integration of AI and ML techniques in the realm of hydrogel development, highlighting their significance in enhancing the design, characterisation, and optimisation of hydrogels for diverse applications. We introduced the concept of AI train hydrogel design, underscoring its potential to decode intricate relationships between hydrogel compositions, structures, and properties from complex data sets. In this work, we outlined classical physical and chemical techniques in hydrogel design, setting the stage for AI/ML advancements. These methods provide a foundational understanding for the subsequent AI-driven innovations. Numerical and analytical methods empowered by AI/ML were also included. These computational tools enable predictive simulations of hydrogel behaviour under varying conditions, aiding in property customisation. We also emphasised AI’s impact, elucidating its role in rapid material discovery, precise property predictions, and optimal design. ML techniques like neural networks and support vector machines that expedite pattern recognition and predictive modelling using vast datasets, advancing hydrogel formulation discovery are also presented. AI and ML’s have a transformative influence on hydrogel design. AI and ML have revolutionised hydrogel design by expediting material discovery, optimising properties, reducing costs, and enabling precise customisation. These technologies have the potential to address pressing healthcare and biomedical challenges, offering innovative solutions for drug delivery, tissue engineering, wound healing, and more. By harmonising computational insights with classical techniques, researchers can unlock unprecedented hydrogel potentials, tailoring solutions for diverse applications.

David del-Bosque, Josefina Vila-Crespo, Violeta Ruipérez et al.

Glucose oxidase (GOX) and catalase (CAT) were co-immobilized in silica–calcium–alginate hydrogels to degrade must glucose. The effect of the enzyme dose (1.2–2.4 U/mL), the initial must pH (3.6–4.0), and the incubation temperature (10–20 °C) on the glucose consumption, gluconic acid concentration, pH, and color intensity of Verdejo must was studied by using a Box–Behnken experimental design and comparing free and co-immobilized enzymes. A reduction of up to 37.3 g/L of glucose was observed in co-immobilized enzyme-treated must, corresponding to a decrease in its potential alcohol strength of 2.0% vol. (<i>v</i>/<i>v</i>), while achieving a slight decrease in its pH (between 0.28 and 0.60). This slight acidification was due to a significant reduction in the estimated gluconic acid found in the must (up to 73.7%), likely due to its accumulation inside the capsules. Regarding the operational stability of immobilized enzymes, a gradual reduction in glucose consumption was observed over eight consecutive cycles. Finally, co-immobilized enzymes showed enhanced efficiency over a reaction period of 48 h, with an 87.1% higher ratio of glucose consumed per enzyme dose in the second 24 h period compared with free enzymes. These findings provide valuable insights into the performance of GOX–CAT co-immobilized to produce reduced-alcohol wines, mitigating excessive must acidification.

Dimitrios Psaltis

The Kerr-Newman metric is the unique vacuum solution of the General Relativistic field equations, in which any singularities or spacetime pathologies are hidden behind horizons. They are believed to describe the spacetimes of massive astrophysical objects with no surfaces, which we call black holes. This spacetime, which is defined entirely by the mass, spin, and charge of the black hole, gives rise to a variety of phenomena in the motion of particles and photons outside the horizons that have no Newtonian counterparts. Moreover, the Kerr-Newman spacetime remains remarkably resilient to many attempts in modifying the underlying theory of gravity. The monitoring of stellar orbits around supermassive black holes, the detection of gravitational waves from the coalescence of stellar-mass black holes, and the observation of black-hole shadows in images with horizon-scale resolution, all of which have become possible during the last decade, are offering valuable tools in testing quantitatively the predictions of this remarkable solution to Einstein's equations.

Hao Huang, Katherine R. Davis, H. Vincent Poor

The long-term resilient property of ecosystems has been quantified as ecological robustness (RECO) in terms of the energy transfer over food webs. The RECO of resilient ecosystems favors a balance of food webs' network efficiency and redundancy. By integrating RECO with power system constraints, the authors are able to optimize power systems' inherent resilience as ecosystems through network design and system operation. A previous model used on real power flows and aggregated redundant components for a rigorous mapping between ecosystems and power systems. However, the reactive power flows also determine power systems resilience; and the power components' redundancy is part of the global network redundancy. These characteristics should be considered for RECO-oriented evaluation and optimization for power systems. Thus, this paper extends the model for quantifying RECO in power systems using real, reactive, and apparent power flows with the consideration of redundant placement of generators. Recalling the performance of RECO-oriented optimal power flows under N-x contingencies, the analyses suggest reactive power flows and redundant components should be included for RECO to capture power systems' inherent resilience.

Vittorio De Falco

The general relativistic Poynting-Robertson (PR) effect is a very important dissipative phenomenon occurring in high-energy astrophysics. Recently, it has been proposed a new model, which upgrades the two-dimensional (2D) description in the three-dimensional (3D) case in Kerr spacetime. The radiation field is considered as constituted by photons emitted from a rigidly rotating spherical source around the compact object. Such dynamical system admits the existence of a critical hypersurface, region where the gravitational and radiation forces balance and the matter reaches it at the end of its motion. Selected test particle orbits are displayed. We show how to prove the stability of these critical hypersurfaces within the Lyapunov theory. Then, we present how to study such effect under the Lagrangian formalism, explaining how to analytically derive the Rayleigh potential for the radiation force. In conclusion, further developments and future projects are discussed.