Adaptive passivity-based control extended for unknown control direction.

This research extends the design of adaptive passivity-based controllers (APBC), proposing a normalized APBC (NAPBC) for nonlinear dynamical systems with a direction of control unknown. The plant also has an accessible single-input and a single-output, smooth behavior, linear explicit parametric dependence, and unknown parameters. The proposed method can handle unknown control direction through an alternate and more straightforward method than Nussbaum gains, having two fewer parameters. We present the stability proof of the controlled system. Besides, the proposed NAPBC expands the tuning method for normalized fixed gains or time-varying gains, reducing the trial and error procedure. Finally, we apply the proposed methodology step by step to a conical tank-scale pilot plant. Comparative experimental results show the proposed NAPBC has better indexes ISI, Ess, MO, IAE, and Ts.

Tricobezoar gastroduodenal en la edad escolar: Caso clínico / Gastroduodenal Trichobezoar in school age: Case report

Los bezoares son acumulaciones de sustancias orgánicas en el tracto gastrointestinal. El tricobezoar hace referencia a la acumulación de cabello, por lo general, en el estómago e incluso más allá de este (síndrome de Rapunzel). La incidencia de esta enfermedad es extremadamente rara; el 90 % de los casos se presentan en las mujeres, y el 80 % de estos ocurren en menores de 30 años y se encuentran relacionados con conductas de ansiedad y trastornos psiquiátricos. El abordaje integral en estos pacientes es fundamental, junto con el seguimiento interdisciplinario, para tratar las causas psicoemocionales subyacentes y realizar una adecuada psicoeducación con los pacientes y sus familiares, para disminuir el riesgo de posibles recidivas. Se presenta el caso clínico de una paciente en edad escolar, con antecedente de maltrato físico por parte de su padrastro y posteriores conductas ansiosas (tricotilomanía y tricofagia).

Bezoar is an accumulation of organic substances in the gastrointestinal tract; trichobezoar refers to the accumulation of hair usually in the stomach and even beyond it (Rapunzel syndrome). The incidence of this condition is extremely rare, 90 % of cases occur in women, and 80 % of these occur in those under 30 years of age and are related to anxiety behaviors and psychiatric disorders. The integral approach in these patients is fundamental, together with the interdisciplinary follow-up, treating the underlying psycho-emotional causes and adequate psychoeducation with the patients and their relatives, in order to reduce the risk of possible recurrences. We present the clinical case of a patient of school age, with a history of physical abuse by her stepfather and subsequent anxious behaviors (trichotillomania and trichophagia).

[Gastroduodenal Trichobezoar in school age: Case report]. / Tricobezoar gastroduodenal en la edad escolar: Caso clínico.

Bezoar is an accumulation of organic substances in the gastrointestinal tract; trichobezoar refers to the accumulation of hair usually in the stomach and even beyond it (Rapunzel syndrome). The incidence of this condition is extremely rare, 90 % of cases occur in women, and 80 % of these occur in those under 30 years of age and are related to anxiety behaviors and psychiatric disorders. The integral approach in these patients is fundamental, together with the interdisciplinary follow-up, treating the underlying psycho-emotional causes and adequate psychoeducation with the patients and their relatives, in order to reduce the risk of possible recurrences. We present the clinical case of a patient of school age, with a history of physical abuse by her stepfather and subsequent anxious behaviors (trichotillomania and trichophagia).

Los bezoares son acumulaciones de sustancias orgánicas en el tracto gastrointestinal. El tricobezoar hace referencia a la acumulación de cabello, por lo general, en el estómago e incluso más allá de este (síndrome de Rapunzel). La incidencia de esta enfermedad es extremadamente rara; el 90 % de los casos se presentan en las mujeres, y el 80 % de estos ocurren en menores de 30 años y se encuentran relacionados con conductas de ansiedad y trastornos psiquiátricos. El abordaje integral en estos pacientes es fundamental, junto con el seguimiento interdisciplinario, para tratar las causas psicoemocionales subyacentes y realizar una adecuada psicoeducación con los pacientes y sus familiares, para disminuir el riesgo de posibles recidivas. Se presenta el caso clínico de una paciente en edad escolar, con antecedente de maltrato físico por parte de su padrastro y posteriores conductas ansiosas (tricotilomanía y tricofagia).

A Deep Neural Network Based Model for a Kind of Magnetorheological Dampers.

In this paper, a deep neural network based model for a set of small-scale magnetorheological dampers (MRD) is developed where relevant parameters that have a physical meaning are inputs to the model. An experimental platform and a 3D-printing rapid prototyping facility provided a set of different conditions including MRD filled with two different MR fluids, which were used to train a Deep Neural Network (DNN), which is the core of the proposed model. Testing results indicate the model could forecast the hysteretic response of magnetorheological dampers for different load conditions and various physical configurations.

Frequency and Temperature Dependence of Fabrication Parameters in Polymer Dispersed Liquid Crystal Devices.

A series of polymer dispersed liquid crystal devices using glass substrates have been fabricated and investigated focusing on their electrical properties. The devices have been studied in terms of impedance as a function of frequency. An electric equivalent circuit has been proposed, including the influence of the temperature on the elements into it. In addition, a relevant effect of temperature on electrical measurements has been observed.

Note: series and parallel tunable resonators based on a nematic liquid crystal cell as variable capacitance.

In this work, tunable series and parallel resonators based on a nematic liquid crystal cell as variable capacitance are proposed and characterized. Tunable resonance frequencies in the range of kHz have been obtained for the combination of the inductance and the liquid crystal cell (capacitance) used in the proposed circuits. Tuning range in frequency obtained is around an octave.

Temperature-frequency converter using a liquid crystal cell as a sensing element.

A new temperature-frequency converter based on the variation of the dielectric permittivity of the Liquid Crystal (LC) material with temperature has been demonstrated. Unlike other temperature sensors based on liquid crystal processing optical signals for determining the temperature, this work presents a system that is able to sense temperature by using only electrical signals. The variation of the dielectric permittivity with temperature is used to modify the capacitance of a plain capacitor using a LC material as non-ideal dielectric. An electric oscillator with an output frequency depending on variable capacitance made of a twisted-nematic (TN) liquid crystal (LC) cell has been built. The output frequency is related to the temperature of LC cell through the equations associated to the oscillator circuit. The experimental results show excellent temperature sensitivity, with a variation of 0.40% of the initial frequency per degree Celsius in the temperature range from -6 °C to 110 °C.

Note: Phase-locked loop with a voltage controlled oscillator based on a liquid crystal cell as variable capacitance.

A phase-locked loop is demonstrated using a twisted-nematic liquid crystal cell as a capacitance that can be varied as a function of applied voltage. The system is formed by a phase detector, a low-pass filter, as well as a voltage controlled oscillator including such variable capacitance. A theoretical study is proposed and experimentally validated. Capture and locked ranges of hundreds of kHz have been obtained for the configuration used in this circuit. An application as frequency demodulator using a practical implementation of this circuit has been demonstrated.

Doble parálisis de los elevadores: a propósito de un caso / Double Elevator Palsy: just about a case

Se presenta el estudio clínico de un caso con doble parálisis de los elevadores (paresia de los músculos recto superior y oblicuo inferior). En el examen clínico se constató limitación de la elevación, tanto en la aducción como en las ducciones, hipotropia del ojo afectado, elevación del mentón y pseudoptosis. La cirugía está indicada, si existe estrabismo vertical en mirada primaria y una elevación significativa del mentón. Si existe restricción del recto inferior, la intervención de elección es una recesión de ese músculo. De no existir restricción del recto inferior, se debe realizar una transferencia del tendón completo de los rectos medio y lateral hasta la inserción del recto superior (operación de Knapp)(AU)

This paper reports a case of double elevator palsy. Clinical examination showed limitation of elevation, both on adduction and on abduccion, hypotropia of the eye involved, chin-up position, and pseudoptosis. Surgery is indicated if strabismus of vertical deviation in primary position, and a significant chin up. If inferior rectus muscle restriction is present, muscle recession is the treatment of choice. If there is no restriction of the inferior rectus, a complete muscle transference must be done of the medial rectus and the lateral rectus muscles up to the insertion of the superior rectus (Knapp procedure)(AU)

Two simple and novel SISO controllers for induction motors based on adaptive passivity.

The design of two single-input single-output (SISO) controllers for induction motors based on adaptive passivity is presented in this paper. The two controllers work together with a field orientation block. Because of the adaptive nature of the proposed controllers, the knowledge of the set motor-load parameters is not needed and robustness under variations of such parameters is guaranteed. Simple proportional controllers for the torque, rotor flux and stator current control loops are used, due to the control simplification given by the use of feedback passive equivalence. A new principle called the "Torque-Flux Control Principle" is also stated in this article, which considerably simplifies the controller design, diminishing the control efforts and avoiding also rotor flux estimation.

MLH1 and MSH2 expression in pterygia.

PURPOSE: Pterygia have been reported to share some of the genetic defects seen in cancers, including microsatellite instability (MSI). We examined pterygia for the presence of proteins typically missing or defective in adenocarcinomas with MSI. We also performed microsatellite analysis on DNA from pterygia to test for instability in the size of the microsatellites, using markers conventionally used to characterize MSI in tumors (Bethesda convention markers). METHODS: We examined 13 pterygia by immunohistochemistry for MLH1 and MSH2, 2 proteins involved in DNA mismatch repair. In addition, we amplified the pterygial DNA with primers specific for 5 Bethesda markers (BAT25, BAT26, D2S123, D5S346, and D17S250). RESULTS: MLH1 staining was present at low levels in the basal cells of the cornea and migrating limbal cells of the pterygia. MSH2 staining was present in basal and in maturing epithelial cells of the cornea and migrating limbal cells of pterygia. We observed no reproducible examples of MSI or loss of heterozygosity (LOH). CONCLUSIONS: We were unable to confirm the presence of MSI and LOH by using the markers we examined. MSH2 staining appeared to be normal in pterygia. MLH1 staining was present but in reduced amounts compared with that seen in the conjunctiva.

Study of biological aerated filters for the treatment of effluents from the citrus industry.

The primary objective of this research study was to test the applicability and optimize the design parameters of a system of biological aerated filters in order to obtain an optimal effluent from the citrus industry, which would allow its drainage into the municipal sewer system. Expanded clay was used as a support material. After experimenting with both countercurrent and cocurrent flows as well different aeration levels, it was found that cocurrent flow was more efficient. Backwashing was carried out on a daily basis. The results of our study showed that for an aeration of 10.47 Nm3/h/m2, the volumetric load should be less than 20 Kg. COD/m3/d in order to obtain an effluent with a maximum concentration of 600 mgCOD/L, and the hydraulic load should be less than 0.36 m/h.

Tracking control of cascade systems based on passivity: the nonadaptive and adaptive cases.

A new cascade passivity-based control scheme for tracking purposes is proposed in this paper. The proposed scheme is valid for a certain class of nonlinear systems even with unstable zero dynamic, and it is also useful for regulation and stabilization purposes. The cases where all system parameters are assumed to be known (nonadaptive case) and also the case when they are unknown (adaptive case) are considered. Some simulation examples are studied to analyze the behavior of the proposed scheme.

Agricultural soils spiked with copper mine wastes and copper concentrate: implications for copper bioavailability and bioaccumulation.

A better understanding of exposure to and effects of copper-rich pollutants in soils is required for accurate environmental risk assessment of copper. A greenhouse experiment was conducted to study copper bioavailability and bioaccumulation in agricultural soils spiked with different types of copper-rich mine solid wastes (copper ore, tailing sand, smelter dust, and smelter slag) and copper concentrate. A copper salt (copper sulfate, CuSO4) that frequently is used to assess soil copper bioavailability and phytotoxicity also was included for comparison. Results showed that smelter dust, tailing sand, and CuSO4 are more likely to be bioavailable and, thus, toxic to plants compared with smelter slag, concentrate, and ore at equivalent total copper concentrations. Differences may be explained by intrinsic differences in copper solubilization from the source materials, but also by their capability to decrease soil pH (confounding effect). The copper toxicity and bioaccumulation in plants also varied according to soil physicochemical characteristics (e.g., pH and total organic carbon) and the available levels of plant nutrients, such as nitrogen, phosphorus, and potassium. Chemistry/mineralogy of mine materials, soil/pore-water chemistry, and plant physiological status thus should be integrated for building adequate models to predict phytotoxicity and environmental risk of copper.

Biotic ligand model prediction of copper toxicity to daphnids in a range of natural waters in Chile.

The objective of this study was to assess the predictive capacity of the biotic ligand model (BLM) for acute copper toxicity to daphnids as applied to a number of freshwaters from Chile and to synthetic laboratory-prepared waters. Thirty-seven freshwater bodies were sampled, chemically characterized, and used to determine the copper concentration associated with the 50% of mortality (LC50) for Daphnia magna, Daphnia pulex, and Daphnia obtusa (native to Chile). The data were then used to run three versions of the acute copper BLM, and the predicted LC50s were compared to the observed ones. The same was done with synthetic assay media at various hardness and dissolved organic carbon (DOC) levels. The BLM versions differed in the affinity constants for some biotic ligand-ion pairs, stability constants for inorganic Cu complexes, and assumptions regarding Cu binding to DOC. All three versions showed a high degree of predictive performance, mostly within a twofold range of observed toxicity values. The D. obtusa data set was used to compare water quality criteria (WQC) derived from the observed toxicity values with those derived from either the BLM or the U.S. Environmental Protection Agency (U.S. EPA) procedure. For most low DOC waters, the three procedures generated similar WQCs. For the high-DOC waters, the EPA-derived criteria were significantly lower, that is, greatly overprotective. The results are also discussed in terms of the validation of the BLM for regulatory use.

Cumplimiento de estándares de calidad en la atención del parto institucional y nivel de satisfacción de usuarias / Meeting standards of quality care and institutional delivery

Objetivos: Determinar la correlación entre el nivel de satisfacción de usuarias y el nivel de cumplimiento de índices estandarizados de atención del parto en 58 establecimientos de salud del Perú. Materiales y Métodos: Se realizó un estudio transversal y comparativo aplicado a una población de 21 departamentos del Perú realizada en forma aleatoria (37 hospitales y 21 centros de salud cabeceras de red. Se utilizaron dos instrumentos: Encuesta de satisfacción a puérperas usuarias de los establecimientos de salud y la lista de chequeo para la medición de procesos de calidad de atención en servicios materno perinatales. Para el análisis de los datos se realizó un análisis bivariado y se utilizó el coeficiente de correlación de Spearman. Resultados: El Coeficiente de Correlación de Spearman entre el "Grado de satisfacción de la puérpera usuaria de los servicios de atención de parto" y el "Porcentaje de cumplimiento del manejo estandarizado de atención del parto" resultó de 0.027, lo que revela la no existencia de relación directa entre dichas variables. Conclusiones: En el presente trabajo se demuestra la falta de correlación entre el nivel de satisfacción de usuarias y el nivel de cumplimiento de índices estandarizados de atención del parto en los Centros Hospitalarios.

Objectives: To determine the correlation between the level of users satisfaction and the fulfillment level of attention childbirth standardized indexes in Peru Health establishments. Methods: A cross-sectional and comparative study was made applied to a population of 58 Health Establishments in 21 departments of Peru made in random form. Two instruments were used: One for the survey of satisfaction to puerperal users and another for the fullfielment attention quality processes measurement in maternal perinatal services. For the analysis of the data a bivaried analysis was made and the Spearman's Correlation Coefficient was used. Results: The Spearman Correlation Coefficient between the principal variables was from 0,027. Conclusions: This work demonstrates the lack of correlation between the users satisfaction level and the level of standardized childbirth attention fulfillment in Health Centers.

Vegetative responses to defoliation of two Chilean matorral shrubs.

This paper reports the results of experimental defoliation of two common matorral species: Lithraea caustica and Colliguaya odorifera. L. caustica and C. odorifera are the matorral species previously shown to exhibit the highest and lowest levels of natural defoliation by browsing. Experimental defoliation was performed at four levels: 0% (controls), 25%, 66%, and 100%. C. odorifera exhibited vegetative responses stronger than controls only in the two highest levels of defoliation (66% and 100%), whereas L. caustica responded vigorously at the 25% and 100% levels. The results are related to the observed position of both species in the matorral community and their relative defoliation risks by natural and introduced herbivores.