This study examined the effect of chemical composition on the overall acceptability of mayonnaise. 22-factorial experimental designs were run, with four chemical compositions, two replicates, and eight mayonnaises per experiment. In the first experiment, the concentrations of an oregano oil extract and table salt were varied. In the second, the amount of oil and egg yolks was modified. The final idea was to use a tasting event to determine the effect of the control variables on the degree of acceptability and improve the formulation to achieve a highly acceptable mayonnaise. The oil extract was obtained by macerating ground oregano leaves in soybean oil. The oil and aqueous phases were prepared by mixing the oregano oil extract with soybean oil and the aqueous phase by mixing egg, salt, sugar, vinegar, mustard, and pepper to achieve the oregano extract and salt concentrations, respectively, according to the experimental design. The mayonnaise was prepared by adding the oil phase in a thin stream to the aqueous phase. Two tasting events were conducted, one for each experiment. For the first, 20 people with little professional knowledge of the culinary arts participated; for the second, 10 experts participated. The results strongly suggest that the effects of oregano and salt concentrations, as well as that of their interaction on the level of overall acceptance, are statistically highly significant. The second experiment showed that the mayonnaises were rated at a high level, global average off 7.66/9; the effects evaluated did not show statistically significant evidence regarding the level of acceptance. It is worth mentioning, however, that culinary professionals showed a preference for mayonnaises with low egg yolk and high oil content.
Activated carbons (ACs) were synthesized from natural precursors (coconut shells and peach pits) via carbonization in a muffle furnace at 700 degrees C, followed by activation with nitric acid (HNO3). The materials were characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Brunauer-Emmett-Teller (BET) analysis to determine the specific surface area (N-2 physisorption). XRD patterns revealed a highly disordered and/or amorphous structure, in which carbon layers are interconnected and intertwined, forming voids associated with porosity. BET surface area analysis showed that nitrogen adsorption increased after nitric acid activation; in all cases, Type I isotherms were observed according to the BDDT classification. SEM analysis indicated that non-activated coconut shell particles were smaller compared to those derived from peach pits. Finally, the CH4 adsorption capacity of both non-activated and activated carbons was evaluated, showing that nitric acid-activated carbons exhibit enhanced adsorption capacity at low temperatures (40 degrees C).
Cocoa pericarp is a waste product in the cocoa industry, but it contains a large amount of bioactive compounds with high antibacterial potential. The objective of this research was to evaluate the antibacterial potential of the ethanolic extract of cocoa pericarp (Theobroma cacao L.) on Staphylococcus aureus and Escherichia coli. The ethanolic extraction was carried out by digestion was performed (Soto Hern & aacute;ndez et al., 2019). Four (4) concentrations (25 mg/mL, 50 mg/mL, 75 mg/mL, and 100 mg/mL) and a negative control (sterilized distilled water) were established. The agar well diffusion method was used (Balouiri et al., 2016). The results showed that S. aureus bacteria were much more sensitive to cocoa pericarp ethanolic extract (CPE) than E. coli, yielding average inhibition zones of 10.8 and 13.53 mm at concentrations of 50 mg/mL and 75 mg/mL, unlike E. coli, which had averages of 9.88 and 9.46 mm at the same concentrations. The concentration with the greatest inhibitory power on both bacteria was 100 mg/mL, yielding average inhibition halo values of 14.84 and 17.68 mm on E. coli and S. aureus, respectively. These results demonstrate that EPC has high antibacterial power on Gram-positive and Gramnegative bacteria, with the former being more susceptible to this natural antimicrobial. In view of the antibacterial properties observed, EPC has the potential to be developed as a natural antimicrobial agent in food preservation.
In today's industrial landscape, competitiveness and operational efficiency rely heavily on robust production systems, where maintenance plays a critical role in ensuring asset reliability and safety. Despite its importance, the literature reveals a lack of standardized guidelines for assessing the effectiveness of these systems. In Venezuela and other Latin American countries, the COVENIN 2500-93 standard has long served as a key reference, yet its outdated framework limits its relevance considering modern technologies and management practices. This study addresses that gap by developing an evaluation manual aligned with current international standards. The methodology combined a comprehensive review of COVENIN 2500-93 and its application in academic and industrial context, with expert surveys to identify outdated procedures and gaps related to global benchmarks. Findings underscore the urgent need to update the standard, particularly in areas such as technology integration, sustainability, energy efficiency, asset management, occupational safety, and documentation process. The proposed manual incorporates the Deming Cycle (PDCA) and an organizational maturity model, structured around twelve key areas. Its implementation enhances maintenance practices, reduces operational costs, and strengthens business competitiveness through a more proactive, efficient, and sustainable approach.
This study presents the synthesis and characterization of two series of semi-interpenetrating polymer network (semi-IPN) hydrogels based on acrylamide (AAm) combined with either itaconic acid (IA) or dimethoxyethyl itaconate (DEI) in a 70:30 molar ratio, incorporating carboxymethyl starch (CMS) in proportions of 0 to 20 wt%. Quantitative yields confirmed the total integration of CMS into the synthetic lattice. Swelling capacity was primarily governed by the nature of the comonomer: AAm/IA systems exhibited super-desiccant behavior, where swelling decreased upon CMS addition due to volume exclusion, whereas CMS enhanced the initial hydrophilicity of AAm/DEI systems. Kinetic analysis revealed anomalous (non-Fickian) transport in both series, with CMS acting as a modulator of diffusive flux. In 0.02 M CuSO4 solutions, the AAm/IA series showed high adsorption efficiency, evidenced by a drastic network contraction and a shift toward a Fickian-controlled mechanism. Finally, 16-week compost biodegradation assays showed that AAm/DEI samples with 20% CMS lost a corresponding amount of mass, whereas control hydro-gels remained intact. This demonstrates that CMS degrades selectively, leaving the polymer matrix intact; thus, CMS functions as a biodegradable j'acket' or 'vest' for the hydrogel. Microorganisms selectively metabolize the polysaccharide component, enhancing the environmental vulnerability of the material while maintaining the structural integrity of the synthetic matrix during service.
Las Piedras is a coastal town on the Paraguan & aacute; Peninsula in Falc & oacute;n State, where a high mortality rate of Sardinella aurita occurred in its bay during October 2009. This event triggered a series of environmental problems that prompted an investigation into the causes of the species' deaths. The research design was non-experimental, field-based, and explanatory. The study examined the physicochemical, environmental, and biological variables of Las Piedras Bay during the period of the phenomenon. The results were analyzed using a one-way analysis of variance with Tukey and Duncan's post-hoc tests. The findings determined that the fish died due to a synergistic effect of oxygen deficiency at night, feeding failure, and thermal stress, resulting from possible stratification of water masses caused by altered environmental conditions in the area due to the El Ni & ntilde;o phenomenon.
The basic form of the systems we will study is x(i)(k+1)=max {a(i1)+x(1)(k),a(i2)+x(2)(k),...,a(in)+x(n)(k)}=max(j){a(ij)+x(j)(k)},i=1,2,...,n. It is common in practice to change the notation somewhat. Addition + will be written as circle times and max will be written as circle plus. This change of notation makes the resemblance with conventional linear difference systems visible: x(i)(k+1)=circle plus(j){a(ij)circle times x(j)(k)},i=1,2,...,n,which in vector notation will be written as x(k+1)=A circle times x(k).Of the latter equation one speaks as a linear (difference) equation in the max-plus algebra, this in clear analogy with linear difference equations in the conventional, 'plus-times', algebra. We will briefly mention the following specializations and/or extensions: axiomatic foundations, minimal realizations, stochastic discrete event systems, min-max-plus systems and nonexpansive mappings, numerical procedures, 'continuous' discrete event systems and the Fenchel transform.
In this research work, predictive machine learning models were developed for the early detection of hepatitis C, given its potential to cause irreversible liver damage. The methodology encompassed the construction and binary categorization of a dataset, followed by rigorous preprocessing that included integrity verification, imputation of missing values, encoding of categorical variables, and numerical scaling. Following a statistical analysis of risk factors, three supervised learning models were trained and compared: XGBoost, Support Vector Machines (SVM), and Random Forest. The evaluation of these computational tools revealed high overall performance, achieving an accuracy based on the Area Under the Curve (AUC) greater than 99%. The analysis of various metrics demonstrated that all three algorithms are highly efficient in identifying potential carriers of the pathology, with SVM and Random Forest standing out for exhibiting the best global predictive performance.
This study aimed to conduct a comparative analysis of the physicochemical and sensory characteristics of three artisanal blackberry wines produced in the towns of Ca & ntilde;o Zancudo (Wine 1), El Valle (Wine 2), and La Azulita (Wine 3), in the state of M & eacute;rida, Venezuela. The evaluation focused on determining their quality and compliance with Venezuelan national regulations. Key parameters such as alcohol content, total and volatile acidity, dry extract, tannin content, reducing and total sugars, and methanol concentration were measured. In addition, a panel of 41 semi-trained tasters performed a sensory evaluation of the samples. The results showed significant differences among the wines. Although all complied with the alcohol content range stipulated by COVENIN Standard 3042, all three wines presented dry extract levels far exceeding those permitted by COVENIN Standard 3287, indicating deficiencies in the standardization of production processes. Wine 2 presented a serious defect due to its high volatile acidity (3.03 g/L), exceeding the limit permitted by COVENIN Standard 3286 and resulting in rejection during the sensory evaluation. Wine 3 received the highest score, with 67.04 points and a preference of 75.61% of the panel, standing out for its sensory balance. The study highlights the need to improve and standardize artisanal production methods to ensure the quality and safety of these wines.
The Jacobsen catalyst has become a benchmark in asymmetric synthesis over the past three decades, particularly in the enantioselective epoxidation of unfunctionalized alkenes. This work provides a critical overview of the structural features, mechanistic insights, and synthetic applications of the (R,R)-Jacobsen catalyst and its analogues. Particular emphasis is placed on its ability to achieve high enantiomeric excess, its commercial availability, and its broad substrate scope. Recent advancements, including metal substitution, heterogeneous immobilization, and the integration of computational approaches, have further expanded the catalyst's utility and improved its sustainability profile. Representative examples from the total synthesis of natural products and pharmacologically active compounds underscore the continued relevance of Jacobsentype systems in contemporary chemistry. Overall, the catalyst stands as a paradigmatic model of selectivity, efficiency, and adaptability in modern stereoselective catalysis, in accordance with the principles of green chemistry.
This work proposes a model-based tuning method for two-degree-of-freedom PID controllers founded on a polynomial approach and fundamental notions of control theory for first-order plus time-delay (FOPTD) systems. The technique achieves rejection of constant disturbance signals through a time response that asymptotically approaches zero with a specified overshoot and settling time. Likewise, tracking with zero steady-state error of persistent reference inputs such as step, ramp, or parabola is also attained. Another contribution of the method is that it allows tuning the four PID controller parameters. Several examples show the ease of implementation of the technique, its effectiveness, and how it can be extended to systems other than FOPTD.
Scientific research on innovation and sustainability in Arab world universities has become a topic of increasing importance in recent decades. The objective of this study is to investigate publications focusing on innovation and sustainability using a bibliometric approach. The study uses the Web of Science Core Collection database and VOS viewer software to analyze bibliometric data from 1995 to 2023. Findings reveal significant growth in innovation and sustainability research in Arab countries over the past decade, with notable contributions from Saudi Arabia, United Arab Emirates (UAE), and Egyptian universities. Collaborations in Saudi Arabia and the UAE are mainly with Chinese academics, while Egyptian research extends to the USA, Europe, and Turkey. Scientific production in innovation and sustainability in the Arab region has grown significantly more than the average in other disciplines, undoubtedly due to the influence of global agreements such as the SDGs of United Nations and the Paris Agreement.
The electrochemical behavior of amlodipine was studied using cyclic voltammetty with a glassy carbon electrode immersed in a 0.4 mg/mL amlodipine solution in phosphate buffer. It was determined that the oxidation process of amlodipine is diffusion-controlled, with significant adsorption of the oxidized product onto the electrode surface. The results show a clear dependence of the anodic peak potential on pH, identifying three linear regions that reflect distinct oxidation mechanisms. In the pH range of 2.14-4.00, the process is dominated by an initial electron transfer without deprotonation. In the range of 5.5-8.2, a coupled transfer of one electron and one proton is observed. In the basic range of pH 9.00-12.40, prior deprotonation facilitates oxidation. The kinetic study reveals an irreversible behavior with a single anodic peak, attributed to the formation of a stable aromatic ring. The charge transfer coefficient a = 0.70 +/- 0.04 indicates a favorable energetic asymmetry that enhances the oxidation of amlodipine. These findings position amlodipine as an excellent candidate for electroanalytical applications, particularly in the development of sensitive and selective voltammetric sensors.
The growing interest in generating and/or consuming products obtained with environmentally friendly technologies, using raw materials from renewable resources, is leading to a focus on residual and untapped biomass sources in the production of lignocellulosic materials. Megathyrsus maximus, an abundant and underutilized biomass widely distributed in our country, is the central focus of this research, which aims to establish its potential for large-scale lignocellulosic material production. To this end, the biomass was subjected to various physical and chemical stages, including cutting, drying, grinding, sieving, delipidation, delignification, and bleaching, to ultimately obtain cellulose. It was found that the drying process at 60 degrees C for 4 hours is equivalent to one month of air drying under ambient conditions. After the refining process, 13.8% cellulose was obtained on a wet basis from the fed biomass. The cellulose obtained was characterized by infrared spectroscopy in comparison with commercial cellulose, demonstrating the quality of the treatment carried out. Furthermore, it was characterized by thermogravimetric analysis and polarized light optical microscopy, which revealed the crystalline nature of the cellulose fibers obtained. In the studied area, between 13.9 tons/ha and 26.9 tons/ha of fresh Megathyrsus maximus (MM) can be harvested, from which it is projected to obtain between 1.7 tons/ha and 3.3 tons/ha of cellulose from the planted MM, demonstrating the potential of Megathyrsus maximus for processing into lignocellulosic substrates.
In the present research work, the effect on hair growth of extracts derived from the rosemary plant (Rosmarinus officinalis) individually (essential oil, hydrolate and alcoholic extract) and together (in the form of a shampoo and hair tonic) was studied in male mice of the C57BL6//BIOU line, divided into 5 different groups: distilled water (AD), essential oil (AE), extract (ER), hydrolate (HR) and minoxidil 5% (MXD). Growth was evaluated for 5 weeks, using two methods: a growth scale with photographic record and the measurement of hairs taken by traction. The hair growth produced by these treatments was contrasted with a negative control group (distilled water) and positive control (minoxidil 5%). The growth scale used showed that the mice of the AE, ER and HR groups exhibited considerable hair growth; however, this scale proved to have serious limitations when evaluating mice with melanocytic nevus. On the other hand, the measurement of hair length showed that the AE, ER and HR groups presented a statistically superior growth than the control groups (p-value < 0.05). Finally, it was concluded that the extracts used in this research (essential oil, hydrolate and alcoholic extract) stimulate hair growth to a greater extent than the commercial drug minoxidil.
The sustained increase in global demand for parcel transportation has intensified operational challenges in air distribution centers, particularly in systems constrained by strict time windows. This study applies the DMAIC methodology to optimize the logistics flow of PRModel-Logistc in Puerto Rico, expressing all operational metrics in normalized time units (T-n), where 1.00 T(n)corresponds to the maximum allowable time to complete the cycle per flight, and economic indicators in normalized financial units (U-n), with 1.00 U(n)equivalent to the fixed cost per flight. Field studies showed that the process exhibited a normalized takt time of 0.19 T(n )per train of five containers, which is insufficient to systematically ensure compli-ance with the temporal constraint T-total <= 1.00 T(n )under high-demand scenarios. The application of the DMAIC cycle made it possible to identify root causes associated with unequal allocation of resources, operational sequencing, and equipment availability, as well as to redesign task distribution to enable parallel unloading in upper and lower cabins. System simulation validated that the implemented improvements increase process capacity to up to 30 containers per flight while remaining within the established time limit (0.95 T-n). At the financial level, the system exhibited robust performance, with a relative income of 4.95 U(n )per flight and an operating profit of 3.95 U-n, values that reflect the efficiency of a logistics model in which per-flight costs are essentially fixed. The results demonstrate that the integrated use of normalized metrics, statistical analysis, and simulation modeling within the DMAIC structure constitutes an effective approach to sustaining operational and economic competitiveness in air-cargo systems facing abrupt increases in demand.
This research deals with the problem of extending the conventional finite automata theory to the study of the equality theorem. For this purpose, an algebraic approach centered on the concepts of semi-rings, recognizable K-subsets and K-Sigma-automata is proposed. The decidability of any pair of recognizable K-subsets is proved in this context. This means that the semiring K must be known well enough to permit such decisions.
The antioxidant capacity of methanolic extracts of Vismia baccifera var. dealbata bark (EMC) and fruit (EMF) was evaluated using the spectrophotometric method of free radical capture DPPH center dot. The extracts were obtained by maceration of the dried and crushed plant material. The antioxidant activity was determined from the decrease in DPPH center dot absorbance at 517 nm, using ascorbic acid as a positive control. The results showed a concentration-dependent inhibition, obtaining IC50 values of 998.18 +/- 187 mu g/mL for EMC and 827.61 +/- 187 mu g/mL for EMF. Both extracts demonstrated moderate free radical neutralization capacity, the fruit fraction being more active. The observed activity suggests the presence of phenolic compounds or flavonoids, which supports the bioactive potential of this species and justifies future phytochemical research aimed at its application in the development of therapeutic or nutraceutical products.
Liver failure remains a critical condition with limited therapeutic options beyond transplantation. The growing demand for alternatives has driven the development of artificial liver support systems (ALS), aimed at emulating essential liver functions. This review addresses the main technological approaches: artificial, bioartificial, and hybrid devices, highlighting their detoxification and metabolic support mechanisms. Key aspects of engineering design are analyzed, such as bioreactor architecture, selection of biocompatible biomaterials, microfluidic dynamics, and 3D bioprinting. Furthermore, the integration of artificial intelligence for real-time monitoring, anatomical modeling, and predictive control is examined. Stem cell-derived liver organoids are presented as emerging platforms for regenerative applications. From a critical perspective, the clinical role of ALS in acute and chronic liver failure is evaluated, as well as its use as a bridge to transplantation. Finally, pending challenges in immunocompatibility, vascularization, and scalability are identified. The future of liver support points to a convergence of engineering, regenerative biology, and artificial intelligence, with the potential to transform personalized liver medicine.
Measurements of X-ray diffraction, differential thermal analysis (DTA) and of magnetic susceptibility , in the temperature range from 2 to 300 K, were carried out on polycrystalline samples of the Cd1-zMnzGa(2)Te(4) alloy system. The X-ray diffraction patterns were used to check the equilibrium conditions and to estimate crystalline parameter values. These values showed the existence of at least two distinct phase regions: one for samples with a concentration z < 0.03, where the CdGa2Te4 phase is present, and another for samples with z > 0.1, where the MnG(2)Te(4) structure is exhibited. The DTA transition temperature values were plotted as a function of alloy composition z. The 1/ vs. T curves indicated that the samples across all composition ranges exhibit spin-glass behavior. From these curves, the Curie-Weiss temperature and constant values were determined. The transition temperature, Tg, was also determined for values of z >= 0.80.
