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The development of biofilms is an interesting strategy to reduce the use of conventional packaging materials to preserve and prolong the shelf life of foods. In this study, different concentrations of sodium alginate (SA) (0, 0.5, 1.0, 1.5 and 2.0% w/v) and glycerol (GL) (6.0, 4.0, 2.0, 1.0 and 0% w/v) on the properties of enriched films with orange peel (OP) powder were investigated. Physical, structural, thermal, mechanical, and barrier properties were characterized. The results revealed that incorporation of glycerol to OP-SA film-making solution trend to flexible and opaque films, while unplasticized sample did not form flexible films and were glossy. Moreover, decreasing glycerol and simultaneously increase alginate content led to decrease film thickness, moisture content, water solubility and oxygen transmission rate, whereas water absorption was increased. It was observed in micrographs that films with 1.5% SA and 1.0% GL had better surface attributes, and a further increase in GL and decrease in SA concentration was not found to be as favorable. Furthermore, FTIR spectra exhibited that intermolecular hydrogen bonding occurred between GL and OP-SA. X-ray diffraction showed that the films crystal structure has been changed significantly when the OP-SA and GL were mixed in. The plasticized films showed higher thermal stability as confirmed by TGA and DSC thermogram. The tensile strength of OP-SA-GL films was enhanced from 0.92 to 7.39 MPa, while elongation at break was decreased significantly from 20.76 to 2.67%. Consequently, orange peel-alginate-glycerol films could potentially be implemented in the food packaging. [ABSTRACT FROM AUTHOR]

This work proposes the design of a commutation function to solve the output voltage trajectory tracking problem in the DC-DC Buck power electronic converter. Through a Lyapunov-type analysis, sufficient conditions are established, taking into account the discontinuous model, to ensure asymptotic convergence to the desired trajectories. Based on this analysis, a state-dependent switching function was designed to guarantee the closed-loop stability of the tracking error. To validate the control performance, circuit numerical simulations were carried out under abrupt disturbances in the source and load of the converter. The results demonstrate that the voltage tracking at the output of the converter is satisfactorily achieved. [ABSTRACT FROM AUTHOR]

This paper presents two novel formulations for scheduling problems, namely order-position hybrid formulation (OPH) and order-disjunctive hybrid formulation (ODH), which extend and combine parts of existing formulation strategies. The first strategy (OPH) is based on sequence position and linear ordering formulations, adding relationships between constraints that allow relaxing some decision variables. The second approach (ODH) is based on linear ordering and disjunctive formulations. In this work, we prove ODH to be the most efficient formulation known so far. The experiments have been carried out with a large set of problems, which consider single machines and identical parallel machines. Computational results show that OPH is better than the rest of the existing formulations for the case of weighted completion objectives, while ODH turns out to be the best approach for most scenarios studied. [ABSTRACT FROM AUTHOR]

Background: Despite the evidence about the negative impact of homophobic and lesbophobic attitudes on the quality of life of these individuals, the World Health Organisation (WHO) continues to report a lack of research and understanding regarding the health of gays and lesbians and LGTB people in general. There is a growing commitment in public health to understand and improve the health and well-being of LGTB people, and it is very important that professionals in social, educational and health care settings are adequately trained and informed to solve the problems that persist in this population. The aim of this study was to identify homophobic and lesbophobic attitudes in a Spanish youth population, analyzing the relationship of these attitudes with sociodemographic, cultural, political and personal variables. Methods: A descriptive, cross-sectional study was carried out with 325 young people aged 18-30 years. The information was collected through the Modern Homophobia Scale of Raja & Stokes, in which sociodemographic and sociocultural variables were also gathered. The data were analyzed and correlations were estimated. Methods: A descriptive, cross-sectional study was carried out with 325 young people aged 18-30 years. The information was collected through the Modern Homophobia Scale of Raja & Stokes, in which sociodemographic and sociocultural variables were also gathered. The data were analyzed and correlations were estimated. Conclusion: Variables such as education level, sexual orientation and political ideology may have a significant influence on the attitudes toward homosexual men and/or lesbian women. Different results were obtained as a function of sex, thus it is important to consider the gender perspective in future studies that tackle this topic. [ABSTRACT FROM AUTHOR]

For this study, procyanidins generated through the autoxidation of (-)-epicatechin (Flavan-3-ol) under mildly acidic conditions (pH = 6.0) were characterized with ultra high-performance liquid chromatography (UHPLC) coupled with tandem mass spectrometry (MS/MS). Two procyanidins (types A and B) and a mix of oligomers were generated through the autoxidation of (-)-epicatechin. The antiproliferative activity of this mixture of procyanidins on MDA-MB-231, MDA-MB-436, and MCF-7 breast cancer cells was evaluated. The results indicate that the procyanidin mixture inhibited the proliferation of breast cancer cells, where the activity of the procyanidin mixture was stronger than that of (-)-epicatechin. Moreover, the mechanism underlying the antiproliferative activity of procyanidins was investigated. The resulting data demonstrate that the procyanidins induced apoptotic cell death in a manner selective to cancerous cells. In particular, they caused the activation of intrinsic and extrinsic apoptotic pathways in the breast cancer cells. The findings obtained in this study demonstrate that the generation of procyanidins in vitro by the autoxidation of (-)-epicatechin has potential for the development of anti-breast cancer agents. [ABSTRACT FROM AUTHOR]

The spike (S) protein of SARS-CoV-2 is a molecular target of great interest for developing drug therapies against COVID-19 because S is responsible for the interaction of the virus with the host cell receptor. Currently, there is no outpatient safety treatment for COVID-19 disease. Furthermore, we consider it of worthy importance to evaluate experimentally the possible interaction of drugs (approved by the Food and Drug Administration) and the S, considering some previously in silico and clinical use. Then, the objective of this study was to demonstrate the in vitro interaction of ivermectin with S. The equilibrium dialysis technique with UV–Vis was performed to obtain the affinity and dissociation constants. In addition, the Drug Affinity Responsive Target Stability (DARTS) technique was used to demonstrate the in vitro interaction of S with ivermectin. The results indicate the interaction between ivermectin and the S with an association and dissociation constant of Ka = 1.22 µM−1 and Kd = 0.81 µM, respectively. The interaction was demonstrated in ratios of 1:50 pmol and 1:100 pmol (S: ivermectin) by the DARTS technique. The results obtained with these two different techniques demonstrate an interaction between S and ivermectin previously explored in silico, suggesting its clinical uses to stop the viral spread among susceptible human hosts. [ABSTRACT FROM AUTHOR]

This paper presents a sliding mode control (SMC) for the "full-bridge Buck inverter–DC motor" system when a photovoltaic (PV) panel is considered as the power supply. The control executes the trajectory tracking task related to the angular velocity of the DC motor shaft without the need for electromechanical sensors. The proposed control is validated through realistic simulation results via Matlab-Simulink. In this regard, the system is constructed by using the electronic components of the specialized power systems library of Simscape. The results of the following four case studies are presented: (i) The performance of the closed-loop system considering two desired angular velocity profiles and three different incident solar irradiance shapes on the PV panel. (ii) An analysis associated with the primary energy source. (iii) A comparison of the proposed SMC versus a passive control. (iv) A study of the current ripple and its relationship with the execution of the tracking control task on the angular velocity. [ABSTRACT FROM AUTHOR]

This paper presents the design of an adaptive controller that solves the synchronization control problem of two identical Nwachioma chaotic systems in a master-slave configuration. The closed-loop stability is guaranteed by means of a Lyapunov-like analysis. With the aim of verifying the feasibility and performance of the proposed approach, a comparison with an active control algorithm is developed at the numerical simulation level. Based on such results, the master-slave Nwachioma chaotic system in closed-loop with adaptive control is now being experimentally tested by using two personal computers and two low-cost Arduino UNO boards. The experimental results not only show the good performance of the adaptive control but also that Arduino UNO boards are an excellent option for the experimental setup. [ABSTRACT FROM AUTHOR]

The westernmost European nucleus of the 5220* Habitat of Community Interest (HCI) is located in the province of Málaga (Andalusia). In this area, the 5220* HCI is characterized by the presence of scrublands of Gymnosporia senegalensis subsp. europaea. This is a relict species in Europe, with inhabits only in the southeast of the Iberian Peninsula. The westernmost Iberian nuclei of the 5220* HCI are constituted by three isolated nuclei (Málaga–Rincón de la Victoria; Torremolinos; and Pizarra). These nuclei have been only partially mapped. The objectives were: to map the 5220* HCI characterized by G. senegalensis subsp. europaea in detail; to evaluate its degree of conservation (DC); and to identify the chronosequences of the evolution of this habitat from 1957 to 2021, and its fragmentation. Our results have contributed to generating a 1:10,000 scale cartography of the habitat. In general, the DC obtained was from good to excellent. With an excellent DC value, one inland locality (Pizarra) was highlighted. However, the highest reduction in the value of DC was observed in the localities of Torremolinos and Málaga–Rincón de la Victoria which, in addition, have reduced the area of occupancy (AOO) and are fragmented. It is important to note that some areas of Málaga–Rincón de la Victoria reached excellent values of DC, indicating the need to carry out protection. [ABSTRACT FROM AUTHOR]

The mechanism is unclear for the reported protective effect of hyperbaric oxygen preconditioning against oxidative stress in tissues, and the distinct effects of hyperbaric oxygen applied after stress. The trained mice were divided into three groups: the control, hyperbaric oxygenation preconditioning, and hyperbaric oxygenation applied after mild (fasting) or hard (prolonged exercise) stress. After preconditioning, we observed a decrease in basal levels of nitric oxide, tetrahydrobiopterin, and catalase despite the drastic increase in inducible and endothelial nitric oxide synthases. Moreover, the basal levels of glutathione, related enzymes, and nitrosative stress only increased in the preconditioning group. The control and preconditioning groups showed a similar mild stress response of the endothelial and neuronal nitric oxide synthases. At the same time, the activity of all nitric oxide synthase, glutathione (GSH) in muscle, declined in the experimental groups but increased in control during hard stress. The results suggested that hyperbaric oxygen preconditioning provoked uncoupling of nitric oxide synthases and the elevated levels of GSH in muscle during this study, while hyperbaric oxygen applied after stress showed a lower level of GSH but higher recovery post-exercise levels in the majority of antioxidant enzymes. We discuss the possible mechanisms of the redox response and the role of the nitric oxide in this process. [ABSTRACT FROM AUTHOR]

By developing a robust control strategy based on the differential flatness concept, this paper presents a solution for the bidirectional trajectory tracking task in the "full-bridge Buck inverter–DC motor" system. The robustness of the proposed control is achieved by taking advantage of the differential flatness property related to the mathematical model of the system. The performance of the control, designed via the flatness concept, is verified in two ways. The first is by implementing experimentally the flatness control and proposing different shapes for the desired angular velocity profiles. For this aim, a built prototype of the "full-bridge Buck inverter–DC motor" system, along with Matlab–Simulink and a DS1104 board from dSPACE are used. The second is via simulation results, i.e., by programming the system in closed-loop with the proposed control algorithm through Matlab–Simulink. The experimental and the simulation results are similar, thus demonstrating the effectiveness of the designed robust control even when abrupt electrical variations are considered in the system. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is the most frequently diagnosed cancer and is the second-most common cause of death in women worldwide. Because of this, the search for new drugs and targeted therapy to treat BC is an urgent and global need. Histone deacetylase 6 (HDAC6) is a promising anti-BC drug target associated with its development and progression. In the present work, the design and synthesis of a new family of dihydropyrazole-carbohydrazide derivatives (DPCH) derivatives focused on HDAC6 inhibitory activity is presented. Computational chemistry approaches were employed to rationalize the design and evaluate their physicochemical and toxic-biological properties. The new family of nine DPCH was synthesized and characterized. Compounds exhibited optimal physicochemical and toxicobiological properties for potential application as drugs to be used in humans. The in silico studies showed that compounds with –Br, –Cl, and –OH substituents had good affinity with the catalytic domain 2 of HDAC6 like the reference compounds. Nine DPCH derivatives were assayed on MCF-7 and MDA-MB-231 BC cell lines, showing antiproliferative activity with IC50 at μM range. Compound 2b showed, in vitro, an IC50 value of 12 ± 3 µM on human HDAC6. The antioxidant activity of DPCH derivatives showed that all the compounds exhibit antioxidant activity similar to that of ascorbic acid. In conclusion, the DPCH derivatives are promising drugs with therapeutic potential for the epigenetic treatment of BC, with low cytotoxicity towards healthy cells and important antioxidant activity. [ABSTRACT FROM AUTHOR]

The design of a robust flatness-based tracking control for the DC/DC Buck converter-DC motor system is developed in this paper. The design of the control considers the dynamics of a renewable energy power source that plays the role of the primary power supply associated with the system. The performance and robustness of the control is verified through simulations via MATLAB-Simulink when abrupt changes in some parameters of the system are taken into account. Also, experiments are performed by using a built prototype of the DC/DC Buck converter-DC motor system, a TDK-Lambda G100-17 programmable DC power supply, MATLAB-Simulink, and the DS1104 board from dSPACE. In this regard, the TDK-Lambda G100-17 is implemented with the aim of emulating photovoltaic panels through the solar array mode for generating the power supply of the system. Thus, both simulations and experiments show the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]