Nonequilibrium stationary states of 3D self-gravitating systems

Three dimensional self-gravitating systems do not evolve to thermodynamic equilibrium, but become trapped in nonequilibrium quasistationary states. In this Letter we present a theory which allows us to a priori predict the particle distribution in a final quasistationary state to which a self-gravitating system will evolve from an initial condition which is isotropic in particle velocities and satisfies a virial constraint 2K=-U, where K is the total kinetic energy and U is the potential energy of the system

Mechanical and biological assessments of braided artificial tendons functionalized with cork extract

The incidence of tendon ruptures has increased over the years, and represents one of the main causes of musculoskeletal injuries that occur annually due to high mechanical loads, degenerative processes, trauma, stretching, chronic overuse, inflammation, etc. In this investigation, a new approach using braids of different materials, namely, biodegradable (lyocell and biodegradable polyester) and non-biodegradable (polyethylene terephthalate (PET)) materials functionalized with natural cork extract was explored. The cork extract was selected due to its biocompatibility and its properties of interest (antioxidants, antimicrobials, anti-inflammatory, antifungals, cell affinity, etc.). The mechanical characterization of the braids was carried out, and lyocell presented properties closer to accepted ranges: extension less than 10%, and tensile strength between 19 and 100 MPa. Loading of the cork extract into the bradding systems was evaluated in three ways: (1) dip coating; (2) surface activation with UV light followed by dip coating; and (3) binding through dopamine coating. The cork extract was found effective in preventing bacterial action and in promoting antioxidant activity. Collected data deemed the proposed strategy as promising for treating tendon lesions, thus improving the quality of life of affected patients. This innovative approach has the potential to revolutionize existing treatment methods, offering solutions for patients with tendon injuries.info:eu-repo/semantics/publishedVersio

Light with tunable non-Markovian phase imprint

We introduce a simple and flexible method to generate spatially non-Markovian light with tunable coherence properties in one and two dimensions. The unusual behavior of this light is demonstrated experimentally by probing the far field and recording its diffraction pattern after a double slit: In both cases we observe instead of a central intensity maximum a line or cross shaped dark region, whose width and profile depend on the non-Markovian coherence properties. Since these properties can be controlled and easily reproduced in experiment, the presented approach lends itself to serve as a testbed to gain a deeper understanding of non-Markovian processes

Effect of Tryptophan Dietary Content on Meagre, Argyrosomus regius, Juveniles Stress and Behavioral Response

Funding Information: This study was supported by the project AQUARAS (MAR-02.01.02-FEAMP-0223). M.C.S. is supported by the Foundation for Science and Technology through an individual contract (2021.01458.CEECIND). Publisher Copyright: © 2023 by the authors.There are a high number of stressors present in aquaculture that can affect fish welfare and quality. One way of mitigating stress response is by increasing dietary tryptophan. In this study, three diets containing 0.5% (Tript1), 0.6% (Tript2), and 0.8% (Tript3) of tryptophan were tested in 32 g juvenile meagre for 56 days. At the end of the trial, survival, growth, and proximate composition were similar between treatments. Significant differences were found in the plasma parameters before and after a stress test consisting of 30 s of air exposure. Blood glucose levels were higher in the post-stress for all treatments (e.g., 63.9 and 76.7 mg/dL for Tript1 before and after the stress test), and the hemoglobin values were lower in the post-stress of Tript1 (1.9 g/dL compared to 3.0 and 2.4 g/dL for Tript2 and Tript3, respectively). In terms of behavior, three tests were carried out (novel tank diving and shoaling assays, and lateralization test), but no significant differences were found, except for the number of freezing episodes during the anxiety test (1.4 for Tript3 compared to 3.5 and 4.2 for the other treatments). This study suggests that supplementation with dietary tryptophan, particularly in higher dosage (0.8%), can reduce anxiety-like behavior in meagre exposure to acute stress (novel tank). Although the remaining results showed mild effects, they provide some clues as to the potential of this amino acid as a stress mitigator in aquaculture.publishersversionpublishe

Sodium alginate-based multifunctional sandwich-like system for treating wound infections

Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.info:eu-repo/semantics/publishedVersio

Physical, thermal, and antibacterial effects of active essential oils with potential for biomedical applications loaded onto cellulose acetate/polycaprolactone wet-spun microfibers

New approaches to deal with the growing concern associated with antibiotic-resistant bacteria are emerging daily. Essential oils (EOs) are natural antimicrobial substances with great potential to mitigate this situation. However, their volatile nature, in their liquid-free form, has restricted their generalized application in biomedicine. Here, we propose the use of cellulose acetate (CA)/polycaprolactone (PCL) wet-spun fibers as potential delivery platforms of selected EOs to fight infections caused by Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Twenty EOs were selected and screened for their minimal inhibitory concentration (MIC), using the antibiotic ampicillin as positive control. The cinnamon leaf oil (CLO), cajeput oil (CJO), and the clove oil (CO) were the most effective EOs, against the Gram-positive (MIC < 22.38 mg/mL) and the Gram-negative (MIC < 11.19 mg/mL) bacteria. Uniform microfibers were successfully wet-spun from CA/PCL with an averaged diameter of 53.9 ± 4.5 µm, and then modified by immersion with CLO, CJO and CO at 2 × MIC value. EOs incorporation was confirmed by UV-visible spectroscopy, Fourier-transformed infrared spectroscopy, and thermal gravimetric analysis. However, while microfibers contained ampicillin at MIC (control) after the 72 h modification, the CLO, CO and CJO-loaded fibers registered ≈ 14%, 66%, and 76% of their MIC value, respectively. Data showed that even at small amounts the EO-modified microfibers were effective against the tested bacteria, both by killing bacteria more quickly or by disrupting more easily their cytoplasmic membrane than ampicillin. Considering the amount immobilized, CLO-modified fibers were deemed the most effective from the EOs group. These results indicate that CA/PCL microfibers loaded with EOs can be easily produced with increased antibacterial action, envisioning their use as scaffolding materials for the treatment of infections.Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government(OE) for funding the project PEPTEX with reference PTDC/CTM-TEX/28074/2017 (POCI-01-0145-FEDER-028074).Authors also acknowledge project UID/CTM/00264/2020 of Centre for Textile Science and Technology (2C2T),funded by national funds through FCT/MCTES. SEM studies were performed at the Materials CharacterizationServices of the University of Minho (SEMAT/UM)

In vitro gastrointestinal digestion impact on the bioaccessibility and antioxidant capacity of bioactive compounds from tomato flours obtained after conventional and ohmic heating extraction

In times of pandemic and when sustainability is in vogue, the use of byproducts, such as fiber-rich tomato byproducts, can be an asset. There are still no studies on the impact of extraction methodologies and the gastrointestinal tract action on bioactive properties. Thus, this study used a solid fraction obtained after the conventional method (SFCONV) and a solid fraction after the ohmic method (SFOH) to analyze the effect of the gastrointestinal tract on bioactive compounds (BC) and bioactivities. Results showed that the SFOH presents higher total fiber than SFCONV samples, 62.47 ± 1.2459.06 ± 0.67 g/100 g DW, respectively. Both flours present high amounts of resistant protein, representing between 11 and 16% of insoluble dietary fiber. Furthermore, concerning the total and bound phenolic compounds, the related antioxidant activity measured by 2,2-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical cation decolorization assay presented significantly higher values for SFCONV than SFOH samples (p < 0.05). The main phenolic compounds identified in the two flours were gallic acid, rutin, and p-coumaric acid, and carotenoids were lycopene, phytofluene, and lutein, all known as health promoters. Despite the higher initial values of SFCONV polyphenols and carotenoids, these BCs OH flours were more bioaccessible and presented more antioxidant capacity than SFCONV flours, throughout the simulated gastrointestinal tract. These results confirm the potential of ohmic heating to modify the bioaccessibility of tomato BC, enhancing their concentrations and improving their antioxidant capacity.The authors would like to thank to “MultiBiorefinery: Estratégias multiuso para a valorização de uma gama alargada de subprodutos agroflorestais e das pescas: Um passo em frente na criação de uma biorrefinaria” financiado pelo Programa Operacional Competitividade e Internacionalização (POCI-01-0145-FEDER-016403) e pelo Programa Operacional Regional de Lisboa(LISBOA-01-0145-FEDER-016403), na sua componente FEDER e pela Fundação para a Ciência e Tecnologia, I.P. na componente nacional (SAICTPAC/0040/2015). The authors would also like to thank the scientific collaboration under the FCT project UID/Multi/50016/2019, UID-BIM-00009- 2020, and UID/BIO/04469/2020. The author Marta Coelho would like to acknowledge FCT for your grant with the reference (grant number SFRH/BD/111884/2015).info:eu-repo/semantics/publishedVersio

Rheological characterization of xanthan/galactomannans and kappa-carrageenan/galactomannans interactions: Comparison of galactomannans from nontraditional sources with conventional galactomannans

Led by consumers demands, food industry shows a growing interest in the formulation of mixed polysaccharide systems, leading to final products having specific properties and possibly cost advantages. In many systems, the combination of two polysaccharides gives rise to strong synergistic effects. Gels formed by galactomannans (mainly guar gum (GG) and locust bean gum (LBG)) and xanthan or kappa-carrageenan already find extensive applications. In the present work the synergistic interactions of two non-conventional galactomannans (extracted from Gleditsia triacanthos and Sophora japonica seeds) with xanthan and kappa-carrageenan were studied and compared with those obtained with traditional galactomannans (GG and LBG), in order to investigate their ability to provide novel properties to food products and to evaluate their effectiveness as alternative galactomannan sources. This was done by determining the rheological behavior (through dynamic oscillatory measurements) of xanthan/galactomannans and kappa-carrageenan/galactomannans mixtures and evaluating the effects of polymers concentration and temperature in the interaction strength, measured in terms of elastic module. For xanthan/galactomannans systems the maximum synergies were obtained for ratios of 20/80 xanthan/Gleditsia triacanthos galactomannan, 20/80 xanthan/Sophora japonica galactomannan, 40/60 xanthan/GG and 50/50 xanthan/LBG. For kappa-carrageenan/galactomannans mixtures the maximum synergies were obtained for 60/40 kappa-carrageenan/Gleditsia triacanthos galactomannan, 40/60 kappa-carrageenan/Sophora japonica galactomannan, 80/20 kappa-carrageenan/GG and 60/40 kappa-carrageenan/LBG. The higher degrees of synergism were obtained for Sophora japonica galactomannan and LBG followed by Gleditsia triacanthos galactomannan and GG (mannose/galactose ratios of 5/1, 4/1, 3/1 and 2/1, respectively). The differences observed in the gels rheological behavior suggest a dependence upon the fine structure of the galactomannan chain. A decrease of gelling and fusion temperatures was observed for increasing galactomannans concentrations and for decreasing galactomannans mannose/galactose ratio. The results point at a very interesting synergies between the non-conventional galactomannans and xanthan or kappa-carrageenan which can presumably be used in the development of food products with novel properties.info:eu-repo/semantics/publishedVersio

Shear and extensional rheology of galactomannans extracted from seeds of Gleditsia triacanthos and Sophora japonica: comparison with guar gum and locust bean gum

Galactomannans such as guar and locust bean gums are extensively applied in the food industry as thickening and stabilizing agents, due to their low cost and wide range of functional properties, but there is a demand for alternative sources of seed gums to e.g. modify the rheological characteristics, texture and appearance of food products. In this work, two non-conventional galactomannans were isolated from Gleditsia triacanthos and Sophora japonica seeds, and their rheological behaviour, in steady and dynamic shear conditions and in extensional conditions (using a capillary breakup extensional rheometer), was determined and compared to those of guar gum and locust bean gum, in order to investigate their effectiveness as alternative thickening hydrocolloids. The studied galactomannans displayed a shear-thinning behavior and the solutions of Sophora japonica galactomannan exhibited the highest viscosities followed by Gleditsia triacanthos galactomannan, guar gum and locust bean gum solutions (for example, at low shear rates and 1 % of gum, the obtained values were 486.7 Pa.s, 67.8 Pa.s, 67.3 Pa.s and 24.1 Pa.s, respectively). Experimental data in steady shear have been correlated with Cross and Carreau models and both models described the viscosity shear rate data satisfactorily (R2>0.90). The extensional rheology showed that break-up time, relaxation time and elastic module decreased with the decrease of polymer concentration and with the temperature rise. The higher values of these parameters were obtained for the Sophora japonica galactomannan and are in agreement with shear rheology results. These results will contribute to the research of novel renewable sources of hydrocolloids, as alternatives to the traditional ones, and to the development of novel foods, addressing the claims of the modern consumer.info:eu-repo/semantics/publishedVersio