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Kalanchoë gastonis-bonnieri Raym.-Hamet & Perrier is a plant used for medicinal purposes in the treatment of several ailments. The aim of this study was to analyze the chemical profile of extracts from K. gastonis-bonnieri embryogenic calli, generated from genetically transformed roots by Agrobacterium rhizogenes. Putative transformants were verified by PCR. Hydroalcoholic extracts were obtained and the chemical profile was analyzed by LC-ESI-MS/MS. Root formation was obtained from 80% of infected seedlings. Fifteen root lines were isolated, and two lines showed prominent longitudinal growth and profuse branching in the B5 semi-solid medium. In all lines, the formation of nodules and later embryogenic callus was observed. Putative transgenic root lines were cultivated in free-plant growth regulators B5 medium. In the two selected lines, the PCR amplification of rolA, rolB, rolC, rolD, and aux1 genes was detected. The extract of embryogenic calli showed 60 chemical compounds tentatively identified, such as ferulic acid, quinic acid, neobaisoflavone, and malic acid, among others, and the chemical profile was different in comparison to wild-type extracts. This is the first study reporting the analysis of the chemical profile of hairy root extracts derived from Kalanchoë gastonis-bonnieri. This work displays the great potential for obtaining chemical compounds of pharmacological importance from hairy roots and facilitates the identification of new useful drugs against human chronic-degenerative diseases.

Salmonella enterica serovar Typhimurium causes gastroenteritis and systemic infections in humans. For this bacterium the expression of a type III secretion system (T3SS) and effector proteins encoded in the Salmonella pathogenicity island-1 (SPI-1), is keystone for the virulence of this bacterium. Expression of these is controlled by a regulatory cascade starting with the transcriptional regulators HilD, HilC and RtsA that induce the expression of HilA, which then activates expression of the regulator InvF, a transcriptional regulator of the AraC/XylS family. InvF needs to interact with the chaperone SicA to activate transcription of SPI-1 genes including sicA, sopB, sptP, sopE, sopE2, and STM1239. InvF very likely acts as a classical activator; however, whether InvF interacts with the RNA polymerase alpha subunit RpoA has not been determined. Results from this study confirm the interaction between InvF with SicA and reveal that both proteins interact with the RNAP alpha subunit. Thus, our study further supports that the InvF/SicA complex acts as a classical activator. Additionally, we showed for the first time an interaction between a chaperone of T3SS effectors (SicA) and the RNAP.

The design of a novel strategy based on the model reference adaptive control method for the stabilisation of a second-order linear time-delay system with unknown parameters is presented. The proposed approach is developed under the assumption that only one state of the system is available, and the sign of the control gain is known. First, the integral operator is applied to obtain a new representation of the original system, where the whole state is known. The use of the integral operator decomposes the control problem into two subproblems that are solved by using the model reference adaptive control method and the backstepping procedure. The effectiveness of the proposed approach is illustrated through an academic example and a practical application case regarding a chemical reactor recycle system.

In recent years, salinity-induced soil quality impairment and the misuse of management practices have led to the reduced productivity of agroecosystems. This has prompted a search for simple and effective agricultural management strategies that improve the sustainability of agricultural production through soil quality assessments. In this context, the objective of this study was to establish an integrated soil quality index (SQI) by assessing the influence of different types of abiotic stress in two different seasons, using physical, chemical and biological indicators at three sites in the geothermal zone of “Los Negritos”, Michoacán, Mexico. Thirty-nine indicators related to soil fertility attributes and C, N, P, and S cycling—identified as the total dataset (TDS)—were evaluated. Principal component analysis (PCA) and the Spearman correlation matrix (r2 ≥ 0.6) were used to calculate the SQI using an integrated quality index (IQI) equation, with the indicators total nitrogen (TN), cation exchange capacity (CEC), lithium (Li), and zinc (Zn) identified as the minimum dataset (MDS). Significantly higher SQI values related to the better performance of soil functions were detected during the rainy season.

The popping of grains has been mainly used to produce ready-to-eat snacks. However, the popping effect on techno-functional properties and possible industrial applications is still unknown. This work evaluated the physicochemical, thermal, rheological, and techno-functional properties of flours from popped grains (FPG). White sorghum and corn grains were adjusted to initial moisture of 11 and 15% and popped using hot-air (210 °C, 90s). The physicochemical, thermal, rheological, and techno-functional properties were assessed in raw and popped flours. Raw flours showed different physicochemical and techno-functional attributes. However, the popping process homogenized their characteristics, behaving similarly in both FPG. Thermal properties evidenced a complete starch gelatinization in FPG and increased their initial viscosity from 8.4 (raw) to 794 cP. SPG showed a constant viscosity under heating-cooling conditions. The techno-functional properties of FPG showed higher water absorption and solubility (134–160%) values than raw ones. The syneresis was reduced in gels from FPG, reaching less than 3.6% after 48 h of storage. Finally, the FPG gels showed a more elastic matrix with lower deformation and higher cohesion. The techno-functional properties of FPG suggest that they can be used as food additives to improve consistency and stability.

The use of bioabsorbable metals as temporary medical implants has attracted considerable research interest as they do not require a second surgical operation for removal after the healing process is completed. However, magnesium (Mg) and its alloys have a degradation rate that is too high in biological environments. Therefore, it must be controlled using various strategies. In this study, an AZ31-Mg-based alloy coated with CeO2 is investigated to analyse the effect of the coating on its corrosion protection and biocompatibility. The AZ31 alloy is anodised with NaOH solution, before coating to stabilise the alloy surface. The CeO2 coating is deposited on anodised AZ31 by chemical conversion treatment. The electrochemical properties of samples are evaluated using electrochemical impedance spectroscopy and cyclic polarisation curves using Hank’s solution. Structural and morphological characterisation of the samples are performed using X-ray diffraction and scanning electron microscopy–energy dispersive X-ray spectroscopy. Additionally, biocompatibility is determined by live/dead assay using MC3T3-E1 pre-osteoblasts. The preliminary results indicate that CeO2 coatings exhibit higher electrochemical properties. Additionally, an increase in the ratio of live/dead cells of the AZ31OH-CeO2 surface is detected, in contrast with AZ31, thus indicating improvement in biocompatibility upon CeO2 coating.

Four Gram-positive, aerobic, catalase- and oxidase-negative, rod-shaped, motile endophytic bacterial strains, designated NM3R9T, NE1TT3, NE2TL11 and NE2HP2T, were isolated from the inner tissues (leaf and stem) of Sphaeralcea angustifolia and roots of Prosopis laevigata. They were characterized using a polyphasic approach, which revealed that they represent two novel Microbacterium species. Phylogenetic analysis based on 16S rRNA gene sequencing showed that the species closest to NE2HP2T was Microbacterium arborescens DSM 20754T (99.6 %) and that closest to NM3R9T, NE2TL11 and NE2TT3 was Microbacterium oleivorans NBRC 103075T (97.4 %). The whole-genome average nucleotide identity value between strain NM3R9T and Microbacterium imperiale DSM 20530T was 90.91 %, and that between strain NE2HP2T and M. arborecens DSM 20754T was 91.03 %. Digital DNA-DNA hybridization showed values of less than 70 % with the type strains of related species. The polar lipids present in both strains included diphosphatidylglycerol, phosphatidylglycerol, glycolipids and unidentified lipids, whereas the major fatty acids included anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0 and C16 : 0. Whole-cell sugars included mannose, rhamnose and galactose. Strains NM3R9T and NE2HP2T showed physiological characteristics different from those present in closely related Microbacterium species. According to the taxonomic analysis, both strains belong to two novel species. The name Microbacterium plantarum sp. nov. is proposed for strain NE2HP2T (=LMG 30875T=CCBAU 101117T) and Microbacterium thalli sp. nov. for strains NM3R9T (=LMG 30873T=CCBAU 101116T), NE1TT3 (=CCBAU 101114) and NE2TL11 (=CCBAU 101115).

The deposition of bioactive hydroxyapatite (HAp) coatings on pure magnesium (Mg) surfaces was studied. A modification of the biomimetic deposition method was used, which consisted in the incorporation of a supersaturated calcification solution (SCS). Different preparation parameters were modulated to obtain HAp and/or doped apatite coatings with different characteristics. The influence of the surface pre-treatments and soaking time in SCS on the physicochemical properties and the corrosion performance of the biomimetic HAp coatings were evaluated. Two different pre-treatments were explored to condition the sample's surface for the biomimetic HAp deposition. After the surface pre-treatments, the Mg samples were covered with HAp coatings by soaking in SCS during two immersion periods specifically chosen for this study: 2 h and 6 h, respectively. Scanning electron microscopy, coupled with energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman Spectroscopy, and Fourier transform infrared (FTIR), were applied for the chemical, morphological, and structural characterization of the resulting biomimetic HAp-coatings. The in vitro corrosion behavior was studied by open circuit potential (OCP) measurements and electrochemical impedance spectroscopy (EIS) during immersion tests in Ringer's physiological solution for up to 14 days. The results showed that HAp coatings were successfully deposited on the pure Mg substrates. Furthermore, the corrosion studies in Ringer's solution showed that HAp coating behavior depends not only on the pre-treatment type but also on the immersion time in SCS. These results open the door to propose different strategies to control—on demand—the corrosion rate of Mg coated with biomimetic HAp. These systems could be a promising alternative for designing and developing new temporary implants for the human body.

Four different manganese ferrite (MnxFe3–xO4) nanostructures (9 and 15 nm spheres (S1, S2), 18 nm nanoflowers (NFs), and 20 nm cubes (NC)) were prepared in this work through a thermal decomposition method by tuning the critical synthetic parameters. In all of the prepared materials, the cation composition of the ferrite phase was rather similar. The occurrence of a secondary phase of mangano-wüstite within MnxFe3–xO4 nanoparticles and its impact on the magnetic properties were studied in detail from static and dynamic magnetic measurements complemented with Mössbauer spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy (HRTEM) analysis, and X-ray photoelectron spectroscopy (XPS). All of the computed data were consistent with a deterioration of the magnetic output as the reduced phase becomes progressively important, leading to a marked spin disorder and the reduction of either the effective magnetic size or the saturation magnetization. The heating efficiency was measured from 100 up to 300 kHz and from 8 up to 24 kA/m, the NF sample being the one displaying the highest specific absorption rate (SAR) under all tested conditions. These results agreed with the physicochemical and magnetic characterization of the particles, highlighting the interest of the detailed characterization of the particles to understand their heating properties relevant for biomedical applications and others such as catalysis.

Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements

The biological carbon pump is the process that transports carbon vertically out of the mixed layer in the ocean. Besides the sinking flux of organic particles, active flux due to the daily vertical migration of zooplankton and micronekton promotes a significant carbon transport not fully accounted for or understood in the world’s oceans. The diversity and abundance of epipelagic and mesopelagic species in the Gulf of California has been extensively studied, but the role of micronekton in carbon export has not yet been investigated. We studied the carbon flux promoted by juvenile and adult mesopelagic fishes and crustaceans (Decapoda and Euphausiidae) during the transition from the cold to warm period (June) and the onset of the warm season (October) in 2018. We provide the first estimation of migrant biomass and respiratory flux of the most abundant migratory species of mesopelagic fishes, decapods and euphausiids in the Gulf of California. The micronekton species collected accounted for a large biomass of mesopelagic fishes and pelagic crustaceans. The average migrant biomass estimates were 151.5 ± 101.2 mg C·m−2 during June and 90.9 ± 75.3 mg C·m−2 during October. The enzymatic activity of the electron transfer system (ETS) was measured as an estimate of their respiratory rates. Average specific ETS activity was significantly different between fishes and decapods, and between fishes and euphausiids (p < 0.05). The respiratory flux of fishes was predominant in the Gulf of California, followed by pelagic decapods and euphausiids. Seasonal changes in respiratory flux were observed for fishes (June: 6.1 ± 1.5 mg C·m−2·d−1; October: 3.2 ± 1.8 mg C·m−2·d−1) and decapods (June: 0.4 mg C·m−2·d−1; October: 0.7 ± 0.05 mg C·m−2·d−1). Respiratory flux estimation by crustaceans (decapods and euphausiids) and fishes together was 6.86 mg C·m−2·d−1 during June, and 4.21 mg C·m−2·d−1 during October 2018, suggesting a functional role of this large micronektonic fauna in the biologi

The Gulf of California and adjacent Pacific have passed through a prolonged warming period that affects the Humboldt squid D. gigas life cycle, which was the third largest fishery in Mexico until its total collapse after 2010. The aims of the present study were (i) to characterize the nursery habitat of paralarvae of the complex Sthenoteuthis oualaniensis–Dosidicus gigas (SD complex) on the basis of 1112 paralarvae collected from zooplankton trawls carried out during ten oceanographic cruises off northwestern Mexico between 2010 and 2017; and (ii) to model the seasonal and interannual variability of the nursery habitat, applying a generalized additive model (GAM) using a regional long-term (1922–2017) hydrographic database. The GAM showed significant relationships of paralarvae abundance with the seasonal average of thermocline depth, absolute salinity, and conservative temperature. The potential nursery habitat of the SD complex paralarvae showed its maximum expected abundance in the entrance of the Gulf of California during spring, when the thermocline depth was shallowest (<30 m). During summer the nursery habitat moved northward along the Pacific west coast of the peninsula. Autumn and winter were less suitable seasons for paralarvae nursery because the thermocline was deep throughout the area of study. Potential nursery habitat did not change interannually in location during La Niña conditions, but did increase the expected abundance in its southern extension. El Niño events contracted the nursery habitat near Cabo San Lucas, and caused the habitat to move northwards over both coasts of the Baja California peninsula. Despite seasonal and interannual climatic variability, two regions remained suitable habitats almost throughout the year. One was associated with coastal upwelling regions (Cabo Corrientes) and the second comprised the oceanic region of high mesoscale kinetic energy located south of Cabo San Lucas. We conclude that the potential nursery habitat of

[EN] Male rabbit sexual behaviour consists of a single mount followed immediately by ejaculation. In young bucks this pattern changes gradually as they reach sexual satiety in a day and sexual exhaustion after several daily tests. Little is known about the characteristics of sexual behaviour in old rabbits (aged 48-54 mo) within a day and across daily tests leading to sexual exhaustion. By using sexually receptive(young) females, changed within a session to maximise copulation, we found that: a) the inter-ejaculatory interval increased between the first and last days of testing; b) test duration was 3.1 h on day 1 and 0.5 h on day 15; c) the “miss rate” (i.e., mounts not accompanied by ejaculation) significantly increased from the first to the last day of testing, regardless of when this occurred in each individual buck; d) the total number of ejaculations displayed in a session significantly decreased between the first and the last day of testing in all males; e) scent-marking (“chinning”) frequency significantly decreased after copulation to satiety, relative to that quantified at baseline, and was restored the following day. Compared with young bucks our results indicate quantitative, rather than qualitative, differences in sexual behaviour associated with age in rabbits. Specifically, on day 1 old bucks spent a shorter time engaged in copulation and displayed a lower number of ejaculations before reaching satiety than young males. In contrast, the interval between ejaculatory events and the “miss rate” increased across test days in both old and young rabbits. These results merit investigating the neuroendocrine mechanisms underlying the display of such an active sexual behaviour by old rabbit bucks.

[EN] This work optimizes the efficiency of the squirrel cage type Inverter-Induction Machine (IM) system, using an algorithm based on the Interior Point Method (IPM), where the input variables are the electromagnetic torque and the rotor speed at steady state,and as outputs the optimal efficiency and slip values are obtained. The optimum rotor flux value is calculated, which is used as a reference in the flux control loop, in the direct control vector method of the IM. Simulation results are obtained where the increase in efficiency is observed in low load states. The experimental installation used in the implementation of the vector control with maximum system efficiency is described, and the experimental results obtained are shown. A discussion is carried out on the results and the use of the Interior Point Optimization Method., [ES] En este trabajo se realiza la optimización de la eficiencia del sistema Inversor-Máquina de Inducción (MI) del tipo jaula de ardilla, utilizando un algoritmo basado en el Método de Punto Interior (MPI), donde las variables de entrada son el par electromagnético y la velocidad del rotor en estado estacionario, y como salidas se obtienen los valores de la eficiencia óptima y del deslizamiento. Se calcula el valor del flujo óptimo del rotor que se utiliza como referencia en el lazo de control del flujo, en el control vectorial método directo de la MI. Se obtienen resultados de simulación donde se observa el incremento de la eficiencia en estados de baja carga. Se describe la instalación experimental usada en la implementación del control vectorial con máxima eficiencia del sistema, y se muestran los resultados experimentales obtenidos. Se realiza una discusión sobre los resultados y la utilización del Método de Optimización de Punto Interior.

Organic-inorganic hybrid materials overcome drawbacks associated with alginate hydrogels. In this work, covalently coupled silica-alginate hybrids were prepared by Schiff base formation and sol-gel reaction using alginate dialdehyde (ADA), (3- Aminopropyl) triethoxysilane (APTES), and APTES/tetraethylorthosilicate (TEOS) precursors. The influence of the polysaccharide/inorganic ratio, the nature of the inorganic precursor and the ionic crosslinking ability are studied. Prepared hybrids were characterized by FT-IR, 13C and 29Si -NMR spectroscopies, SEM, and rheology. For ADA/APTES hybrids, at higher ADA content, Schiff base formation is predominant, but at lower ADA content, the sol-gel reaction is prevalent. However, the progress of the sol-gel reactions for ADA/(APTES+TEOS), is favored with higher ADA compositions. Introducing a posterior ionic crosslinking treatment was possible, increasing the moduli in ADA/(APTES+TEOS) hybrids from 86207Pa for 1.5 ADA/Si to 362171Pa for 1.5 ADA/Si-Ca. In-situ ADA-Silica hybrid hydrogels containing both ionic and covalent crosslinking can be successfully synthesized with the proposed method.

Early detection of diabetes, a worldwide health issue, is key for its successful treatment. Acetone is a marker of diabetes, and efficient, non-invasive detection can be achieved with the use of nanotechnology. In this paper we investigate the effect of acetone adsorption on the electronic properties of silicon nanowires (SiNWs) by means of density functional theory. We considered hydrogenated SiNWs grown along the [1 1 1] bulk Si axis, with group-III impurities (B, Al, Ga), for which both surface substitutional doping and functionalizing schemes are considered. We present an analysis of the adsorption configuration, energetics, and electronic properties of the undoped and doped SiNWs. Upon acetone adsorption, the SiNW without impurities becomes an n-type semiconductor, while most substituted/functionalized cases have their HOMO-LUMO gap tuned, which could be harnessed in optical sensors. Acetone is always chemisorbed, although for the case without impurities, and the Al- and Ga-functionalization schemes, the chemisorption is very weak. These nanostructures could be used for acetone capture and detection, which could lead to applications in the medical treatment of diabetes.

Sorghum has been used to expand snacks such as pop sorghum. However, it is still unknown how the structural changes during the popping affect its rheological and functional properties. This study evaluated the structural changes of popped sorghum starch (PS) and their impact on rheological behavior. Moisture sorghum was adjusted to 11, 15, and 20% before popped. Morphology, X-ray pattern (XRP), infrared spectra (IR), thermal properties, and rheological behavior before and after popping were evaluated. Micrographs showed a honeycomb-like structure in PS. XRP showed partial damage to the orthorhombic crystals of the sorghum starch after PS, while the growth of crystalline lamellae was also generated (13.08 and 20.01°). IR showed structural damage as the signal at 1045 cm−1 disappeared in PS. The IM increased to gelatinization of the starch. The rheological behavior of PS displayed better thermal stability, with the lowest breakdown (25 ± 3.5 cP), setback (253 ± 11.3 cP), and final (1337 ± 5.7 cP) viscosity. The consistency coefficient k and flow behavior index n increase, meaning a loss of the pseudoplastic character. Viscoelastic properties increased in PS, suggesting the formation of cross-links and a stable matrix. Correlation analysis showed a strong relationship between structural changes and the rheological behavior of PS.

This study aimed at determining the effect of cocoa proteins (CP) on the blood pressure, using in silico, in vitro and in vivo approaches. The in silico assay showed 26 Criollo cocoa peptides with alignment in the Blast® analysis. Peptide sequences ranged from 6 to 16 amino acids, with molecular weight ranging from 560.31 to 1548.76 Da. The peptide sequences LSPGGAAV, TSVSGAGGPGAGR, and TLGNPAAAGPF showed the highest theoretical affinity with −8.6, −5.0, and −10.2 kcal/mol, for the angiotensin-converting enzyme (ACE), renin, and angiotensin II type 1 receptor (AT1-R), respectively. The Criollo CP hydrolysates (CPH) presented in vitro ACE inhibitory activity with an IC50 value of 0.49 mg/mL. Furthermore, the orogastric administration of 150 mg CP/kg/day in rats fed a high-fat (HF) diet (HF + CP group) showed a significant decrease in systolic blood pressure (SBP) by 5% (p < 0.001) and diastolic blood pressure (DBP) by 7% (p < 0.001) compared with the HF group. The human equivalent dose (HED) of CP for an adult (60 kg) is 1.45 g per day. These results suggest that the consumption of CP could reduce blood pressure by blocking ACE, and could be used as an ingredient in the elaboration of antihypertensive functional foods.

This paper evaluates the biodiesel produced by a biodiesel plant located in the Mexican Centre for Cleaner Production (CMP + L by its acronym in Spanish) of the National Polytechnic Institute of Mexico. Pollutant emissions from two types of engines were studied: a low power monocylinder engine and a 30-kW electric generator diesel engine. The tests were performed with the following blends: B5, B10, B15, B20, B30, B40, and B50. Parameters such as carbon monoxide, nitrogen oxide, hydrocarbons, and combustion efficiency were analyzed, as well as sulfur dioxide, oxygen, and combustion temperatures. It was demonstrated that NOx increases as the percentage of biodiesel increases, while CO decreases slightly using the monocylinder engine. In the case of the electric generator diesel engine, the B5 mixture had the highest trend for NOx and the lowest trend for CO. Likewise, combustion efficiency was found to be severely affected by the biodiesel blends, i.e., from B5 to B20. An analytical study and experimental thermography tests of the combustion process with biodiesel blends were carried out, and the technical problems of operation when incorporating biodiesel blends are presented.

The preparation of silica-alginate hybrid hydrogels by a sol-gel route is proposed in this work. The in-situ synthesis of silica networks from tetraethoxysilane (TEOS) and aminopropyltriethoxysilane (APTES) precursors in an alginate matrix is assayed. The experimental parameters were analyzed in three consecutive stages to obtain hybrid materials with specific properties. Stage 1: effect of water and catalyst ratios. Stage 2: effect of the inorganic precursor¿s ratio. Stage 3: effect of concentration of the alginate solution. The hydrolysis-condensation reactions of the silica precursors were regulated by the alginate concentration, the silica precursor nature, and the HCl/inorganic/H2O ratio. Hybrids prepared with both silica precursors generate longer silica chains. High alginate amounts increase the storage modulus of synthesized hybrids, and high catalyst ratios reduce their stability. Compositions with alginate content of 5 and 8 (wt/v)%, TEOS/APTES weight ratio of 74/26, and without catalyst are suitable to evaluation for their application in tissue engineering

The aim of this study was to determine the pancreatic lipase (PL) inhibitory effect of cocoa protein (CP) hydrolysates (CPH) using in silico and in vitro approaches, and an in vivo high-fat diet (HF) obese rat model. The results showed better theoretical affinity on PL for cocoa peptides EEQR, GGER, QTGVQ, and VSTDVNIE released from vicilin and albumins (−6.5, −6.3, −6.2, and −6.1 kcal/mol, respectively). Absorption, distribution, metabolism, and excretion (ADMET) prediction showed the human intestinal absorption (HIA) capacity of orlistat and eight cocoa peptides, demonstrating that they presented a low probability of toxicity with values lower than 0.6, while the orlistat has a high probability of hepatotoxicity with a mean value of 0.9. CPH (degree of hydrolysis of 55%) inhibited PL with an IC50 (concentration needed to inhibit 50% of enzyme activity) value of 1.38 mg/mL. The intragastric administration of 150 mg CP/kg/day to rats increased total lipids and triglycerides excretion in feces, ranging from 11% to 15% compared to the HF-diet. The HF + CP-diet also significantly decreased (p < 0.05) the apparent rate of fat absorption compared with the HF group. These results suggest that CP has anti-obesity potential by inhibiting PL, thus helping to prevent the development of non-communicable diseases.

The preparation of silica-alginate hybrid hydrogels by a sol-gel route is proposed in this work. The in-situ synthesis of silica networks from tetraethoxysilane (TEOS) and aminopropyltriethoxysilane (APTES) precursors in an alginate matrix is assayed. The experimental parameters were analyzed in three consecutive stages to obtain hybrid materials with specific properties. Stage 1: effect of water and catalyst ratios. Stage 2: effect of the inorganic precursor’s ratio. Stage 3: effect of concentration of the alginate solution. The hydrolysis-condensation reactions of the silica precursors were regulated by the alginate concentration, the silica precursor nature, and the HCl/inorganic/H2O ratio. Hybrids prepared with both silica precursors generate longer silica chains. High alginate amounts increase the storage modulus of synthesized hybrids, and high catalyst ratios reduce their stability. Compositions with alginate content of 5 and 8 (wt/v)%, TEOS/APTES weight ratio of 74/26, and without catalyst are suitable to evaluation for their application in tissue engineering.

[EN] Wireless sensor networks (WSNs) have been extensively studied in the literature. However, in hostile environments where node connectivity is severely compromised, the system performance can be greatly affected. In this work, we consider such a hostile environment where sensor nodes cannot directly communicate to some neighboring nodes. Building on this, we propose a distributed data gathering scheme where data packets are stored in different nodes throughout the network instead to considering a single sink node. As such, if nodes are destroyed or damaged, some information can still be retrieved. To evaluate the performance of the system, we consider the properties of different graphs that describe the connections among nodes. It is shown that the degree distribution of the graph has an important impact on the performance of the system. A teletraffic analysis is developed to study the average buffer size and average packet delay. To this end, we propose a reference node approach, which entails an approximation for the mathematical modeling of these networks that effectively simplifies the analysis and approximates the overall performance of the system.

[EN] The goal of this work was the synthesis and characterization of agar membranes for microbial fuel cells applications. Three sets of membranes were synthesized. For a first set of membranes (2, 4, 6, and 8 wt% agar concentration), both proton conductivity (sigma) and O-2 permeability (OP) increased as a function of agar concentration, up to 4 wt% agar. Beyond this concentration, the a levelled-off at 2.43 mS cm(-1) and OP increased. A second one set was obtaining by mixing 2, 4, 6, and 8 wt% concentrations of agar with KC110 wt%. Both a and OP increased as a function of increased agar concentration; nevertheless, the presence of KCl slightly affected in a negative way the OP. For the last set, agar concentration was fixed at 2 wt%, while KCl concentration was increased to 2, 4, 6, 8, and 10 wt%. The a did not significantly increase with salt concentration and the worst values of OP were observed. It was thus confirmed that agar concentration plays a significant role in the increase of a, but KCl does not improve membrane performance. Moreover, the agar membranes cost is two orders of magnitude lower than Nafion (R) 117. Therefore, the best membranes were those produced solely with agar.

El objetivo de este documento es mostrar la existencia de un patrón de reversión a la media en la serie de precios reales del petróleo exportado por México al continente Americano, durante el período comprendido entre Enero de 1999 y Junio de 2017. Con ese fin adaptamos una ecuación en diferencias estocástica a la serie de precios de la variedad Maya para hacer pronósticos dentro y fuera de la muestra, con una ventana de seis y doce meses. Los principales resultados obtenidos muestran que, en efecto, hay una reversión a la media de largo plazo en los precios inicialmente supuestos como racionales. Otras pruebas estadísticas confirman que esta reversión a la media es persistente en virtud de que los shocks producidos sobre los precios reales no involucran cambios permanentes.

[EN] In this work, a control system is developed to allow a manipulator to learn and plan trajectories from demonstrations given by the hand of an user. The input of data is acquired by a sensor, and its behavior is learned through an automatic learning algorithm based on the recursive least squares. A trajectory profile of interpolators to stretches is used to avoid the impulsive jerk on manipulators motion. Direct and inverse kinematics analysis is done for obtaining the joints variables values of the manipulator. A dynamic model is created using Newton-Euler formulation. A proportional derivative control is applied to the system. The monitoring and control systems are implemented in an embedded platform for testing purposes., [ES] En este trabajo, se desarrolla un sistema de control automatizado para permitir que un manipulador aprenda y planifique las trayectorias a partir de las demostraciones dadas por la mano de un usuario. La entrada de datos es adquirida por un sensor, y se aprende su comportamiento a través de un algoritmo de aprendizaje automático basado en los mínimos cuadrados recursivos. Se utiliza un perfil de trayectoria de interpoladores a tramos para evitar el movimiento impulsivo del manipulador. Se realiza el análisis de las cinemáticas directa e inversa para obtener los valores de las variables articulares para el manipulador. Se crea un modelo dinámico usando la formulación de Newton-Euler. Se aplica un control proporcional derivativo al sistema. Los sistemas de monitoreo y control se implementan en una plataforma embebida para fines de prueba.

Bio-oil upgrading by hydrotreatment has been considered as a renewable route for fuels production and potential substitutes for fossil oil distillates. Traditional hydrodesulfurization catalysts (sulfided CoMo and NiMo) used in petroleum refining have been evaluated in hydrodeoxygenation reactions with high selectivity to aromatics. However, significant deactivation has been commonly observed, due to the low sulfur content in bio-oil. Thus, the development of different active and stable catalytic materials is needed. In this regard, we have previously reported a synergetic effect between Ni and Ru bimetallic materials supported on Al2O3, TiO2 and ZrO2 in phenol HDO with promising activity and selectivity results. In particular, materials supported TiO2 on displayed the highest activities. Therefore, the aim of this work was to evaluate the effect of calcination on dispersion and metal-support interactions and their impact on activity and selectivity for NiRu/TiO2 catalysts in HDO of phenol as a model compound for bio oil. Catalysts were characterized by hydrogen chemisorption, Temperature- programmed reduction, X-ray photoelectron spectroscopy, High resolution electron microscopy. Additionally, hydrogenation of benzene was used as a structure unsensitive reaction in order to obtain more information about metallic dispersion. A highly active NiRu catalyst was obtained when calcination was avoided prior to reduction. The calcination procedure induced the formation of metallic oxides and it provoked less dispersed NiRu species as compared with catalysts without this previous treatment. On the contrary, the formation of metallic species from direct reduction of precursor salts contributed to produce highly dispersed species.

This review focuses on recently developed alginate injectable hydrogels and alginate composites for applications in bone tissue regeneration, and it evaluates the alternatives to overcome the problems that avoid their utilization in the field. Section 2 covers the properties of alginates that have made them useful for medical applications, in particular their ionic gelling ability for preparing injectable compositions used as delivery drugs systems. The advantages and shortcomings of these preparations are revised together with the chemical modifications assayed. Section 3 describes how it has been taken advantage of alginates into the new field of biofabrication and the developments in bone engineering. The state of the art of this field is reviewed. Finally in section 4, new developments and approaches that in opinion of the authors can lead to a breakthrough in bone tissue engineering using alginates are introduced.

These data display evidence of the fracture through the morphologies and the topographical features as well as roughness data of different ratios of R(recycled)-PET/PLA, PET(virgin)/PLA, PET(virgin)/Chitosan and R(recycled)-PET/chitosan. Also, data of the morphologies after degradation under accelerated weathering test and degradation mechanisms are revealed. The data supplement the article “Comparative assessment of miscibility and degradability on PET/PLA and PET/chitosan blends”.

[EN] Mesquite pods contain a high nutritional content, then a protein rich flour can be obtained. Prosopis Laevigata pods were collected from Oaxaca and Durango. Three stages of maturity were identified. The internal structure of the pods was analyzed by scanning electron microscopy (SEM). The pods were dried at 40°C, 50°C and 60°C, 10% relative humidity and air velocity of 2.6 m/s. From experimental data, the characteristic curve was obtained. SEM Images showed a heterogeneous and tortuous structure. The internal structure of the material is a limiting factor for mass transfer. The effective coefficient diffusion for each drying experiment was determinated.

[EN] Ethnic foods are healthy products interesting for the new societies. Mesquite flour offers another option for making gluten-free recipes as part of a diet for people with celiac disease. The physicochemical properties of mesquite flours (Prosopis laevigata) were characterized. The mesquite pods were dried at 60°C, 15% RH and 2 m/s airflow; then a grinding and sieving process were applied. The nutritional composition and the sorption isotherms were obtained at 30, 35, 40 and 45°C for water activities of 0.07-0.9. The particle-size distribution, morphology and thermal stability of the flours were determined by different methods.

Ruta graveolens L., comúnmente denominada ruda, es una planta que pertenece a la familia Rutaceae, nativa de la región del Mediterráneo. La ruda sintetiza grupos de metabolitos de interés en medicina y en agricultura, tales como alcaloides y cumarinas, flavonoides, ácidos fenólicos, aceites esenciales, terpenos y glucósidos. Aunque tradicionalmente la extracción de estos compuestos se realiza principalmente por maceración, el empleo de técnicas exhaustivas de extracción como la extracción por líquidos presurizados (PLE) permite reducir el tiempo de extracción y el volumen de disolvente empleado. En este trabajo se aplicó PLE para la extracción de compuestos de interés, tanto en la parte aérea como en la raíz de ruda. Para ello, se empleó 1 g de material vegetal deshidratado y molido, cuya extracción se realizó a distintas condiciones de temperatura (40, 105 y 170 °C) y utilizando distintas combinaciones de disolvente (d-limoneno (100%), acetato de etilo (100%) y una mezcla 50:50 (v/v) d-limoneno – acetato de etilo), con el objetivo de mejorar la selectividad en el aislamiento de ciertas familias de compuesto de interés farmacológico. Se evaluó el rendimiento del extracto y la abundancia de los distintos grupos de metabolitos (alcaloides, furanocumarinas, cumarinas, terpenos, aminas y otros) identificados mediante GC-q-TOF-MS. El mejor rendimiento de los extractos de la parte aérea (16.48 %) y raíz (18.11%) de ruda se obtuvo con d-limoneno a 170°C. En los extractos de la parte aérea extraídos con d-limoneno (100%) y la mezcla d-limoneno acetato de etilo (50:50 v/v), los terpenos y las furanocumarinas fueron los grupos más abundantes, mientras que en los extractos de raíz los alcaloides fueron el grupo de compuestos más abundante. En ambos extractos se identificaron alcaloides, terpenos y furanocumarinas. La arborinina es un alcaloide que solo se identificó en la parte aérea, mientras que en los extractos de raíz se identificaron cumarinas, amidas, y dos furanocumarin

El romero (Rosmarinus officinalis L.) es una planta utilizada en la industria alimentaria, cosmética y farmacéutica que produce compuestos con actividad antioxidante, antibacteriana y antiinflamatoria. En estudios de análisis químico se han identificado como compuestos mayoritarios al ácido carnósico, carnosol y ácido rosmarínico. En cultivos in vitro de romero se acumulan moléculas sintetizadas por la planta silvestre. El objetivo de este trabajo fue analizar el perfil químico de tres líneas celulares de Rosmarinus officinalis L. Se establecieron cultivos de células desdiferenciadas a partir de explantes de hoja en medio Murashige y Skoog (MS) adicionado con sacarosa (30 g/L), fitagel (3 g/L), ácido 2,4-diclorofenoxiacético (1.5 mg/L) y 6-bencilaminopurina (2.0 mg/L). Se analizó el proceso de desdiferenciación celular mediante análisis digital de imágenes con el software ImageJ® y se seleccionaron las líneas celulares. La extracción de los compuestos de romero por maceración se llevó a cabo con etanol absoluto. Los extractos de las líneas celulares se analizaron mediante cromatografía en capa fina (TLC), cromatografía en capa fina de alta resolución (HPTLC), cromatografía de gases acoplada a espectrometría de masas (GC-MS) y cromatografía de líquidos acoplada a espectrometría de masas en tándem (UHPLC-MS/MS). Los resultados permiten identificar tres etapas durante el proceso de desdiferenciación en explantes de romero, definidas como: adaptación del tejido al medio de cultivo, inducción al proceso de desdiferenciación celular y duplicación de células desdiferenciadas. Se logró obtener tres líneas celulares denominadas RoG (línea celular verde), RoY (línea celular amarilla), RoW (línea celular blanca). Se observaron diferencias en el perfil químico de las tres líneas celulares mediante TLC y HPTLC y se identificaron los compuestos de cada línea mediante GC-MS y UHPLC-MS/MS.

In this work, a double-layered chemical conversion coating, which consists of a bluing layer followed by a cerium oxide layer, was applied to reinforcing steel (RS) to increase its corrosion resistance under field conditions. The corrosion behaviour of the blued reinforcing steel specimens (BRS) in 3% sodium chloride with and without the top layer of cerium oxide was assessed by open-circuit potential, linear polarisation resistance, potentiodynamic polarisation curves, and electrochemical impedance spectroscopy. Scanning electron microscopy coupled with energy-dispersive spectrometry, X-ray diffraction, and atomic force microscopy were used to characterise the blued and cerium conversion layers. The best electrochemical behaviour of RS was attained by the bluing sample sealed for 10 min in 0.001 M CeCl (B10 + cerium chemical conversion treatments). Under these conditions, the potential shifted in the noble direction from E to approximately 600–800 mV and the corrosion current density decreased by five orders of magnitude as compared to bare RS.

The aim was to investigate the potential of germinated soybean proteins as a source of peptides with anticancer and anti-inflammatory activities produced after simulated gastrointestinal digestion. Protein concentrate from germinated soybean was hydrolysed with pepsin/pancreatin and fractionated by ultrafiltration. Whole digest and fractions >10, 5-10 and <5 kDa caused cytotoxicity to Caco-2, HT-29, HCT-116 human colon cancer cells, and reduced inflammatory response caused by lipopolysaccharide in macrophages RAW267.4. Antiproliferative and anti-inflammatory effects were generally higher in 5-10 kDa fractions. This fraction was further purified by semi-preparative chromatography and characterised by HPLC-MS/MS. The most potent fraction was mainly composed of ß-conglycinin and glycinin fragments rich in glutamine. This is the first report on the anti-cancer and anti-inflammatory effects of newly isolated and identified peptides from germinated soybean released during gastrointestinal digestion. These findings highlight the potential of germination as a process to obtain functional foods or nutraceuticals for colon cancer prevention.

[EN] This paper presents the direct and easy way to implement digitally a Sünter-Clare modulation algorithm for a 7.5 KVA, three-wires, matrix converter. This modulation algorithm is used to calculate 3x3 matrix converter duty cycles to produce constant output voltage and frequency signals. The Sünter-Clare modulation algorithm recalculates switching patterns and switching times every sampling period in order to compensate the input voltage and frequency variations. This algorithm is defined in terms of the three-phase input and the output reference voltages at each sampling instant and is convenient for closed loop operations when the input voltage and frequency are variable in time as in the variable speed wind generation system. The experimental control setup is comprised of a field programmable gate array board, a digital signal processor and a graphics interface board., [ES] En este trabajo se presenta la implementación digital del algoritmo de modulación de Sünter-Clare, para un convertidor matricial de tres hilos de 7.5 kVA. Este algoritmo es usado para calcular los ciclos de trabajo en un convertidor matricial 3x3, con lo que se generan tensiones de salida con amplitud y frecuencia constantes. El algoritmo de modulación de Sünter-Clare recalcula los tiempos y trayectorias de conmutación cada período de muestreo, con el objetivo de compensar las variaciones de amplitud y de frecuencia de las tensiones de entrada. Este algoritmo se ejecuta en cada muestreo y está en función de la tensión trifásica de entrada y de la tensión de referencia de salida, resultando adecuado para controles en lazo cerrado, cuando las señales de amplitud y de frecuencia de las tensiones de entrada son variables en el tiempo, como ocurre en los sistemas de generación de energía eléctrica a velocidad variable, que utilizan la energía del viento como fuente primaria de energía. El sistema de control para el trabajo experimental, además de la tarjeta del convertidor matricial, está compuesto por una tarjeta de arreglos de compuertas programable (FPGA) y por un procesador digital de señales (DSP) con una tarjeta de interfaz gráfica.

We believe we are at the beginning of a new Big Bang. This great explosion places us at the dawn of a new era in learning Physics, and we would like to participate in this fascinating process. Mobile devices are exponentially growing amongst our students, so we are convinced that they must be used to promote active learning. In this work, we will focus on several apps from Wolfram Research Company: Wolfram Alpha, Wolfram Alpha Viewer, Physics I and Physics II. All of them have many possibilities to achieve an autonomous and active learning. These apps allow users to select different options from a specific menu, enter values of the required parameters and the app calculates by itself the magnitude involved in the process. In addition, these apps also allow us to study the major laws of Physics, to look for the different units of the International System of Units or even to manage the most common physical constants. We are convinced that there is a necessity of developing more applications for smartphones that will empower a meaningful learning of Physics using apps for the operating systems iOS, Android, Windows Phone and those that arise in the future. This opportunity, which is provided to us by the new technologies, cannot be unexploited. We must strongly engage into this topic to achieve a meaningful learning.

Marine and coastal ecosystems provide multiple benefits that are fundamental to human wellbeing, but human actions are disrupting and impacting the Earth's ecosystems at an alarming rate. The Ecopath approach was designed to understand the impact of the wide range of anthropogenic pressures that are exerted on the oceans, and of management options for countering these, and it has over the last thirty years grown into a complex and capable modelling framework: “Ecopath with Ecosim” – with Ecospace added on. Exciting new developments of the approach are contributing to address critical and complex issues related to the health of marine ecosystems such as invasion of species, illegal fishing activities, climate change and the development of new activities (e.g., aquaculture and infrastructure development) in coastal areas. This Special Issue presents new findings from selected case studies around the world using advanced features of Ecopath with Ecosim that were presented at the International Conference “Ecopath 30 Years-Modelling ecosystem dynamics: beyond boundaries with EwE” (November 2014, Barcelona, Spain). These contributions showcase new capabilities and findings of Ecopath with Ecosim models applications. Together these papers show that a range of diverse ecological, economic, social and governance drivers are often interacting at dynamic and temporal scales to modify marine resources, which underlines that managing marine ecosystems needs a continuous effort to integrate multiple processes

[ES] En este trabajo se desarrollaron algoritmos computacionales los cuales permiten segmentar y detectar los automóviles que se encuentran dentro de una nube de puntos 3D pertenecientes a un entorno urbano. Las nubes son adquiridas con el sistema LIDAR velodyne HDL-64E, el cual es capaz de reconstruir objetos que se encuentran a una distancia de 3 a 120 metros. El desarrollo del trabajo está dividido en dos etapas: la segmentación de objetos 3D y la indexación. Se considera que el ambiente es semi estructurado debido a que objetos como las fachadas de los edificios y el suelo pueden ser modelados por planos. La segmentación está compuesta por tres módulos: el primero consiste en la extracción del plano principal o suelo; en el segundo módulo se extraen los planos perpendiculares al suelo, los cuales son segmentados por una adaptación al método de Hough; y en el último módulo se aplica una segmentación a los objetos restantes usando el método MeanShift. La indexación está dividida en dos módulos: en el primero, los objetos segmentados son modelados por histogramas usando las direcciones de las normales de los puntos 3D de los objetos; en el segundo módulo, los histogramas son usados para comparar con una biblioteca de datos previamente construida. En este trabajo hemos usado el análisis ROC para optimizar los umbrales empleados. Se utilizan dos bases de datos: la primera es de entrenamiento y está compuesta por 4500 objetos; mientras que la segunda corresponde a la de prueba, la cual está compuesta por 3000 objetos y fue usada para verificar los resultados de entrenamiento. La aportación de este trabajo es presentar un nuevo sistema para detectar automóviles utilizando puntos 3D., [EN] Detection of vehicles on 3D point clouds is performed by using the algorithm presented in this work. Point clouds correspond to urban environments and were acquired with the LIDAR Velodyne HDL-64E. The environment is considered semi-structured so that can be modeled using planes.Vehicle detection is carried out on to stages, segmentation and indexation. First stage is at the same time composed of three sub-stages. In the first one the principal plane (in this case the floor) is extracted, in the second sub-stage secondary planes are extracted using a tailored version of Hough's method, secondary planes are those perpendicular to the main plane. Finally in the third sub-stage and using MeanShift method, the remaining objects are segmented.Indexation on its side is divided into two sub-stages, in the first one, last segmented objects using MeanShift method are modeled using histograms according to the direction of the object's 3D points normal; in the second stage histograms are compared to those previously stored on a database of object's histograms. Optimizing of detection thresholds was carried out through ROC analysis. Two databases were used during the experiments, the first DB have 4500 objects and was used for ROC analysis training; the second one contained 3000 objects and was used for verification.

This work has been focused on the synthesis and characterization of different blended membranes SPEEK-35PVA (Water), SPEEK-35PVA (DMAc) prepared by casting and nanofiber-reinforced proton exchange membranes Nafion-PVA-15, Nafion-PVA-23 and SPEEK/PVA-PVB. The two first reinforced membranes were made up of Nafion (R) polymer deposited between polyvinyl alcohol (PVA) nanofibers. The last composite membrane is considered because the PVA is a hydrophilic polymer which forms homogeneous blends with SPEEK suitable to obtain high proton conductivity, while the hydrophobic PVB can produce blends in a phase separation morphology in which very low water uptake can be found. The synthesized membranes showed an outstanding stability, high proton conductivity, and enhanced mechanical and barrier properties. The membranes were characterized in single chamber microbial fuel cells (SCMFCs) using electrochemically enriched high sodic saline hybrid H-inocula (Geobacter metallireducen, Desulfurivibrio alkaliphilus, and Marinobacter adhaerens) as biocatalyst. The best performance was obtained with Nafion-PVA-15 membrane, which achieved a maximum power density of 1053 mW/m(3) at a cell voltage of 340 mV and displayed the lowest total internal resistance (Rint approximate to 522 Omega). This result is in agreement with the low oxygen permeability and the moderate conductivity found in this kind of membranes. These results are encouraging towards obtaining high concentrated sodic saline model wastewater exploiting MFCs.

Three-dimensional distribution of larval fish habitats was analyzed, from the upper limit of the shallow oxygen minimum zone (~0.2 mL/L) to the sea surface, in the eastern tropical Pacific Ocean off Mexico in February 2010. The upper limit rises from ~250 m depth in the entrance of the Gulf of California to ~80 m depth off Cabo Corrientes. Three larval fish habitats were defined statistically: (i) a Gulf of California habitat dominated by Anchoa spp. larvae (epipelagic species), constrained to the oxygenated surface layer (>3.5 mL/L) in and above the thermocline (~60 m depth), and separated by a salinity front from the Tropical Pacific habitat; (ii) a Tropical Pacific habitat, dominated by Vinciguerria lucetia larvae (mesopelagic species), located throughout the sampled water column, but with the highest abundance in the oxygenated upper layer above the thermocline; (iii) an Oxygen Minimum habitat defined mostly below the thermocline in hypoxic (<1 mL/L; ~70 m depth) and anoxic (<0.2 mL/L; ~80 m depth) water off Cabo Corrientes. This subsurface hypoxic habitat had the highest species richness and larval abundance, with dominance of Bregmaceros bathymaster, an endemic neritic pelagic species; which was an unexpected result. This may be associated with the shoaling of the upper limit of the shallow oxygen minimum zone near the coast, a result of the strong costal upwelling detected by the Bakun Index. In this region of strong and semi-continuous coastal upwelling in the eastern tropical Pacific off Mexico, the shallow hypoxic water does not have dramatic effects on the total larval fish abundance but appears to affect species composition.

[EN] The present work deals with the tracking problem of a mobile robot (3,0) based on the kinematic model and proposes a control strategy that takes into account a priori input signals bounds i.e. the linear and angular velocity of the robot. The objective of this control approach is to maximize the effectiveness of the actuators without taking a risk in the system stability. The resulting nonlinear control is composed of a nonlinear compensator based on the kinematic model and nested saturation approach. The control law can be tuned to force the error dynamics trajectories to enter in a neighborhood of the origin in a finite time and remain thereafter. Experimental results show the performance of the closed loop system. Furthermore, owing to simplicity, the proposed control law is suitable for application where on-board computational resources are limited., [ES] El presente trabajo aborda el problema de seguimiento de trayectoria para el robot (3, 0) basado en su modelo cinemático y propone una solución mediante el diseño de una estrategia de control que a priori toma en cuenta las cotas máximas permitidas de la señal de control i.e. la velocidad lineal y angular máximas que puede alcanzar el robot móvil. El objetivo es maximizar el uso de los actuadores sin poner en riesgo la estabilidad del sistema. La ley de control no lineal resultante se compone de un compensador no lineal basado en el modelo cinemático y de funciones de saturación anidadas. Esta ley de control contiene parámetros de sintonización que permiten que las trayectorias de la dinámica del error ingresen a una vecindad del origen, en un tiempo finito y se mantengan de ah́ı en adelante. Resultados experimentales sustentan los resultados teóricos, muestran el desempeño del sistema de control en lazo cerrado y lo comparan con una estrategia que no toma en cuenta los ĺımites de la señal de control. Debido a su simplicidad, la estrategia de control propuesta permite ser implementada en sistemas embebidos con bajo coste computacional.

[EN] This paper presents the estimation considering the Second Probability Moment applied to a simplified Third Order Stochastic Process. Model commonly used to describe smoothing systems as a synchronous motor. Its values used into the model describe and estimate the Black Box system behavior. In the design three parameters based on covariance Pk and Qk are calculated The stochastic variable depends on the three gains and three functional estimation errors, respectively, developing the stochastic identification by a reference model that converges in almost all points with 10 iterations in recursive estimation. The results demonstrate a theoretical experiment using the Matlab obtaining the parameters and the third order model to converge in accordance to the reference signal. The accuracy achieved in thousandths was in a Supermartingale sense and implementation performed as a function of recursive estimation., [ES] En este artículo se propone un estimador basado en el segundo momento de probabilidad aplicado a un modelo estocástico de tercer orden en diferencias finitas. Modelo que comúnmente es usado para describir sistemas con amortiguamiento como es el caso de los motores síncronos. Los valores que se consideran en el modelo son resultado de la estimación con respecto a la señal de referencia. En el diseño se realiza el cálculo de los tres parámetros usando las covariancias Pk y Qk. Es así como la variable estocástica observable está en función sus ganancias y del proceso de innovación, lo que permite el desarrollo de un identificador con convergencia en casi todos los puntos a la señal de referencia. Para contar con los resultados en línea así como lograr una implementación se realiza la estimación recursiva. En la sección de resultados se presenta un experimento teórico utilizando la herramienta de Matlab® para determinar los parámetros y lograr la convergencia del modelo de tercer orden con la señal de referencia, lo cual se logró en menos de diez iteraciones. La convergencia se puede observar a través del funcional del error. La aproximación del identificador con la estimación recursiva hacia la referencia fue de milésimas y es descrita como una supermartingala.

[ES] En este trabajo, se presenta un controlador no lineal para estabilizar el sistema Péndulo Invertido Sobre Dos Ruedas. Como primera etapa la estrategia de control, se basa en una linealización parcial por realimentación, para posteriormente proponer una función candidata de Lyapunov en combinación con el principio de invariancia de LaSalle con el fin de obtener el controlador esta- bilizador. El sistema en lazo cerrado obtenido es asintóticamente estable localmente alrededor del punto de equilibrio inestable, con un dominio de atracción calculable., [EN] In this paper, a nonlinear controller is presented for the stabilization of the two wheels inverted pendulum. The control strategy is based on partial feedback linealization, in first stage and then a suitable function Lyapunov in conjunction with LaSalle's invariance principle is formed to obtain a stabilizing feedback controller. The obtained closed-loop system is locally asymptotically stable around its unstable equilibrium point, with a computable domain of attraction.

[ES] Se presenta un método novedoso para controlar la obtención de espectros de energía de oleajes, de gran utilidad en los laboratorios de investigación y desarrollo de Hidráulica Marítima. El elemento final de control o manipulador es un motor eléctrico lineal conectado a un servo-control el cual es supervisado mediante una computadora. El algoritmo de control automático se realiza con un esquema neuronal combinado, compuesto por una red neuronal artificial “feed-forward” y un controlador proporcional integral. El sistema computacional implementado incluye características de autoaprendizaje, materializado en el re-entrenamiento en línea de la red neuronal lo cual hace posible adaptarse a cambios en los parámetros del “proceso controlado” y a perturbaciones, altamente influyentes en el espectro de energía que impacta una obra hidráulica objeto de estudio., [EN] A novel method is presented to control the generation of wave energy spectrum, useful in research and development laboratories of Maritime Hydraulic. The final control element is a linear electric motor connected to a servo-control which is monitored by a computer. The automatic control algorithm is performed with a combined neural scheme. It consists of an artificial neural network “feed-forward” and a proportional integral controller. The computer system includes self-learning based on an online training of the neural network. It makes possible to adapt to changes in the parameters of the “controlled process” and disturbances that impact the studied hydraulic work.

This paper presents the analysis of the two usual control structures for variable speed and fixed pitch wind energy generation systems, namely speed and torque control, to determine the most appropriate structure to improve both robustness and reliability of this kind of distributed generators. The study considers all the elements of a typical wind power generation system and it has been carried out in a general way, so that conclusions are independent of the kind of the AC/DC converter that it is used to process the energy at the output of the generator. Particular emphasis was placed on developing a model of the turbine where the mechanical torque is considered as a system variable and not an exogenous disturbance for the system, as in other previous studies. After showing that speed control presents several advantages in terms of stability and reliability, an experimental study of this technique was carried out by using a grid connected wind generation system, which is composed by a three-phase boost rectifier feeding the grid connected inverter. Other practical issues for the design of high efficient wind generation systems, like the use of a Kalman speed estimator to avoid the need of mechanical sensors, are also implemented in the prototype and discussed in the paper. (c) 2012 Elsevier Ltd. All rights reserved.

In the framework of a left-right model containing mirror fermions with gauge group SU(3)(C) circle times SU(2)(L) circle times SU(2)(R)circle times U(1)(Y'), we estimate the neutrino masses, which are found to be consistent with their experimental bounds and hierarchy. We evaluate the decay rates of the Lepton Flavor Violation (LFV) processes mu -> e gamma, tau -> mu gamma and tau -> e gamma. We obtain upper limits for the flavor-changing branching ratios in agreement with their present experimental bounds. We also estimate the decay rates of heavy Majorana neutrinos in the channels N -> W(+/-)l(-/+), N -> Z nu(l) and N -> H nu(l), which are roughly equal for large values of the heavy neutrino mass. Starting from the most general Majorana neutrino mass matrix, the smallness of active neutrino masses turns out from the interplay of the hierarchy of the involved scales and the double application of seesaw mechanism. An appropriate parameterization on the structure of the neutrino mass matrix imposing a symmetric mixing of electron neutrino with muon and tau neutrinos leads to tribimaximal mixing matrix for light neutrinos.

[EN] The synthesis of planar mechanism represents an attractive problem to be solved using evolutionary techniques as it involves an underdetermined nonlinear set of equations that grow in number as more precision points are defined to describe the desired trajectory of the coupler. This paper presents a Genetic Algorithm (GA) based approach for optimisation of the kinematical synthesis of a 6-bar Watt type mechanism for prosthetic knee applications. The desired trajectory to be described by the coupler corresponds to the trajectory of the knee during a normal gait cycle. The generated trajectory illustrates how it naturally evolves from an erratic solution to a smooth fitted curve., [ES] La síntesis de mecanismos planos representa un problema atractivo para ser resuelto mediante técnicas de computación evolutiva, ya que ésta plantea un sistema indeterminado de ecuaciones no lineales cuyo tamaño es directamente dependiente del número de puntos de precisión definidos para describir la trayectoria deseada del acoplador. Este artículo presenta la optimización en el proceso de síntesis de mecanismos basado en algoritmos genéticos (AG) para el caso de un mecanismo plano de seis barras tipo Watt utilizado como base para el diseño de una prótesis policéntrica de rodilla. La trayectoria deseada a ser descrita por el acoplador corresponde a la descrita por la rodilla durante un ciclo normal de marcha. La metodología propuesta ilustra claramente como, por la aplicación de AG’s, la trayectoria generada evoluciona de manera natural desde una solución errática hasta una curva que se ajusta suavemente a la trayectoria deseada.