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1.
MethodsX ; 12: 102762, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38826795

RESUMEN

This article addresses the impact of transient pressure anomalies in hydraulic systems, triggered by the opening or closing of valves or pumps, instantly disturbing the line of hydraulic gradient (LGH). This variation in pressure has significant consequences both in hydraulic and structural terms for water networks. Most of the existing techniques to detect transients in water distribution systems use asynchronous methods, generating timeless information that limits the response capacity in critical situations. Therefore, an automatic transient detection system based on the Internet of Things (IoT) is proposed, capable of identifying overpressure or underpressure pulses in soft real-time, activating alarms to facilitate decision-making. This approach helps maintain the safety of the water distribution system and prevent leaks in the network. Furthermore, a model of the transient behavior of pressure and flow is presented by linearizing the water hammer equations from the Laplace transform, thus generating a transfer function that describes the algebraic relationship between the outlet and inlet of the hydraulic system.•The transient analysis of the hydraulic system prototype underscores its high sensitivity to initial conditions, attributed to turbulence. This observation suggests the possible presence of a dynamic strange attractor related to water hammer phenomena in pressure pipes.•The methodology involving transfer functions and state-space models enables the assessment of how leaks impact the transient responses of the system, including the magnitude, duration, and frequency of disturbances generated by them.•The proposed method introduces a dynamic transfer function capable of identifying instantaneous changes over time in terms of flow and pressure.

2.
MethodsX ; 12: 102620, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38445177

RESUMEN

In this study, we propose a method based on phase space reconstruction to estimate the short-term future behavior of pressure signals in pipelines. The pressure time series data were obtained from an IoT experimental model conducted in the laboratory. The proposed hydraulic system demonstrated the presence of traces of weak chaos in the time series of the pressure signal. Fractal dimension analysis revealed a complex fractal structure in the data, indicating the existence of nonlinear dynamics. Similarly, Lyapunov coefficients, divergent trajectories, and autocorrelation analysis confirmed the presence of weak chaos in the time series. The results demonstrated the existence of apparently chaotic patterns that follow the theory proposed by Kolmogorov for deterministic dynamic systems that exhibit apparently random behaviors. Phase space reconstruction allowed us to show the dynamic characteristics of the signal so that short-term predictions were stable. Finally, the study of strange attractors in pipeline pressure time series can have significant contributions to anomaly detection.•A methodology is proposed for the reconstruction of the phase space to estimate the short-term future behavior of pressure signals in pipelines in real time.•The analysis of the proposed hydraulic system revealed some indications of weak chaos in the time series of the pressure signal obtained experimentally.•The methodology implemented and the results of this study showed that the short-term predictions were very accurate and consistent; Chaotic patterns were also identified that support the theory proposed by Kolmogorov.

3.
Cell Prolif ; 56(2): e13353, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36305033

RESUMEN

OBJECTIVES: Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that are widely used in various products. PFAS are characterized by their fluorinated carbon chains that make them hard to degrade and bioaccumulate in human and animals. Toxicological studies have shown PFAS toxic effects: cytotoxicity, immunotoxicity, neurotoxicity, and reproductive toxicity. However, it is still unclear how the structures of PFAS, such as carbon-chain length and functional groups, determine their reproductive toxicity. METHODS AND RESULTS: By using a mouse-oocyte-in-vitro-maturation (IVM) system, we found the toxicity of two major categories of PFAS, perfluoroalkyl carboxylic acid (PFCA) and perfluoroalkyl sulfonic acid (PFSA), is elevated with increasing carbon-chain length and the inclusion of the sulfonate group. Specifically, at 600 µM, perfluorohexanesulfonic acid (PFHxS) and perfluorooctanesulfonic acid (PFOS) reduced the rates of both germinal-vesicle breakdown (GVBD) and polar-body extrusion (PBE) as well as enlarged polar bodies. However, the shorter PFSA, perfluorobutanesulfonic acid (PFBS), and all PFCA did not show similar adverse cytotoxicity. Further, we found that 600 µM PFHxS and PFOS exposure induced excess reactive oxygen species (ROS) and decreased mitochondrial membrane potential (MMP). Cytoskeleton analysis revealed that PFHxS and PFOS exposure induced chromosome misalignment, abnormal F-actin organization, elongated spindle formation, and symmetric division in the treated oocytes. These meiotic defects compromised oocyte developmental competence after parthenogenetic activation. CONCLUSIONS: Our study provides new information on the structure-toxicity relationship of PFAS.


Asunto(s)
Fluorocarburos , Técnicas de Maduración In Vitro de los Oocitos , Animales , Humanos , Alcanosulfonatos , Fluorocarburos/toxicidad , Fluorocarburos/química
4.
Sci Rep ; 12(1): 10540, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35732675

RESUMEN

In vitro production (IVP) of embryos in cattle can result in large/abnormal offspring syndrome (LOS/AOS) which is characterized by macrosomia. LOS can cause dystocia and lead to the death of dam and calf. Currently, no test exists to identify LOS pregnancies. We hypothesized that fetal ultrasonography and/or maternal blood markers are useful to identify LOS. Bovine fetuses were generated by artificial insemination (control) or IVP. Fetal ultrasonographies were taken on gestation D55 (D55) and fetal collections performed on D56 or D105 (gestation in cattle ≈ D280). IVP fetuses weighing ≥ 97 percentile of the control weight were considered LOS. Ultrasonography results show that the product of six D55 measurements can be used to identify extreme cases of LOS. To determine whether maternal blood can be used to identify LOS, leukocyte mRNA from 23 females was sequenced. Unsupervised hierarchical clustering grouped the transcriptomes of the two females carrying the two largest LOS fetuses. Comparison of the leukocyte transcriptomes of these two females to the transcriptome of all other females identified several misregulated transcripts on gestation D55 and D105 with LOC783838 and PCDH1 being misregulated at both time-points. Together our data suggest that LOS is identifiable during pregnancy in cattle.


Asunto(s)
Perfilación de la Expresión Génica , Inseminación Artificial , Animales , Bovinos , Femenino , Feto , Inseminación Artificial/veterinaria , Embarazo , Ultrasonografía Prenatal
5.
GigaByte ; 2022: gigabyte50, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36824514

RESUMEN

Between 2012 and 2014, 715 green coffee samples were gathered by Almacafé S.A. (Bogotá, Colombia) from 27 countries. These were analysed at the nuclear magnetic resonance (NMR) laboratory at Universidad del Valle (Cali, Colombia). Over 1000 methanolic coffee extracts were prepared and 4563 spectra were acquired in a fully automatic manner using a 400 ï»¿MHz NMR spectrometer (Bruker Biospin, Germany). The dataset spans the variance that could be expected for an industrial application of origin monitoring, including samples from different harvest times, collected over several years, and processed by at least two distinct operators. The resulting 1D and 2D spectra can be used to develop and evaluate feature extraction methods, multivariate algorithms, and automation monitoring techniques. They can also be used as datasets for teaching, or as a reference for new studies of similar samples and approaches.

6.
PLoS One ; 16(12): e0260123, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34882691

RESUMEN

Serum supplementation during bovine embryo culture has been demonstrated to promote cell proliferation and preimplantation embryo development. However, these desirable outcomes, have been associated with gene expression alterations of pathways involved in macroautophagy, growth, and development at the blastocyst stage, as well as with developmental anomalies such as fetal overgrowth and placental malformations. In order to start dissecting the molecular pathways by which serum supplementation of the culture medium during the preimplantation stage promotes developmental abnormalities, we examined blastocyst morphometry, inner cell mass and trophectoderm cell allocations, macroautophagy, and endoplasmic reticulum stress. On day 5 post-insemination, > 16 cells embryos were selected and cultured in medium containing 10% serum or left as controls. Embryo diameter, inner cell mass and trophectoderm cell number, and macroautophagy were measured on day 8 blastocysts (BL) and expanded blastocysts (XBL). On day 5 and day 8, we assessed transcript level of the ER stress markers HSPA5, ATF4, MTHFD2, and SHMT2 as well as XBP1 splicing (a marker of the unfolded protein response). Serum increased diameter and proliferation of embryos when compared to the no-serum group. In addition, serum increased macroautophagy of BL when compared to controls, while the opposite was true for XBL. None of the genes analyzed was differentially expressed at any stage, except that serum decreased HSPA5 in day 5 > 16 cells stage embryos. XBP1 splicing was decreased in BL when compared to XBL, but only in the serum group. Our data suggest that serum rescues delayed embryos by alleviating endoplasmic reticulum stress and promotes development of advanced embryos by decreasing macroautophagy.


Asunto(s)
Medios de Cultivo/farmacología , Embrión de Mamíferos/citología , Marcadores Genéticos/efectos de los fármacos , Suero/química , Animales , Blastocisto , Bovinos , Proliferación Celular/efectos de los fármacos , Medios de Cultivo/química , Técnicas de Cultivo de Embriones , Embrión de Mamíferos/efectos de los fármacos , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/efectos de los fármacos , Estrés del Retículo Endoplásmico , Regulación del Desarrollo de la Expresión Génica , Macroautofagia/efectos de los fármacos
7.
J Korean Neurosurg Soc ; 61(3): 407-414, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29631381

RESUMEN

OBJECTIVE: The purpose of the present study was to describe an OrBitoZygomatic (OBZ) surgical variant that implies the drilling of the orbital roof and lateral wall of the orbit without orbitotomy. METHODS: Design : cross-sectional study. Between January 2010 and December 2014, 18 patients with middle fossa lesions underwent the previously mentioned OBZ surgical variant. Gender, age, histopathological diagnosis, complications, and percentage of resection were registered. The detailed surgical technique is described. RESULTS: Of the 18 cases listed in the study, nine were males and nine females. Seventeen cases (94.5%) were diagnosed as primary tumoral lesions, one case (5.5%) presented with metastasis of a carcinoma, and an additional one had a fibrous dysplasia. Age ranged between 27 and 73 years. Early complications were developed in four cases, but all of these were completely resolved. None developed enophthalmos. CONCLUSION: The present study illustrates a novel surgical OBZ approach that allows for the performance of a simpler and faster procedure with fewer complications, and without increasing surgical time or cerebral manipulation, for reaching lesions of the middle fossa. Thorough knowledge of the anatomy and surgical technique is essential for successful completion of the procedure.

8.
San Salvador; s.n; 2008. 50 p. Tab, Graf, Ilus.
Tesis en Español | LILACS, BISSAL | ID: biblio-1247931

RESUMEN

Lamendin et al (1992) desarrollo una técnica general para la estimación de edades en adultos utilizando dos parámetros: la periodontitis y la traslucidez radicular; evaluar los resultados de dicha técnica, mediante la coincidencia con la edad real del sujeto, en dos grupos poblacionales de salvadoreños es el objetivo general por el cual se desarrollo este estudio; donde se busca especificamente determinar la edad (cabe mencionar que es un rango) con 20 muestras de sujetos vivos pertenecientes a los municipios de San Vicente y Santa Clara del Departamento de San Vicente; y, 10 muestras de cadáveres proporcionados por Medicina Legal de San Salvador. Dicho estudio, se llevo a cabo en el periodo de Agosto a Diciembre del año 2007, en los departamentos de san Vicente para los sujetos vivos, y de noviembre a enero de 2008, en El Departamento de San Salvador, para los cadáveres. A los cuales se les aplico la técnica de Lamendin obteniendo un 70% de acierto de la técnica tanto para vivos como para cadáveres. Se hizo una comparación de porcentajes para la corroboración de ello. En base a los resultados antes mencionados, se concluye que al utilizar la técnica desarrollada por Lamendin et al., se puede obtener resultados muy favorables y de gran ayuda para la identificación de edad de un cadáver, lo cual podría agilizar el reconocimiento del individuo; y sobre todo, aplicable a la población salvadoreña.


Lamendin et al (1992) developed a general technique for estimating ages in adults using two parameters: periodontitis and root translucency; Evaluating the results of this technique, by coinciding with the real age of the subject, in two population groups of Salvadorans is the general objective for which this study was developed; where it is specifically sought to determine the age (it is worth mentioning that it is a range) with 20 samples of living subjects belonging to the municipalities of San Vicente and Santa Clara in the Department of San Vicente; and, 10 samples of corpses provided by Legal Medicine of San Salvador. This study was carried out in the period from August to December 2007, in the departments of San Vicente for living subjects, and from November to January 2008, in the Department of San Salvador, for corpses. To which the Lamendin technique was applied, obtaining a 70% success rate of the technique for both living and corpses. A comparison of percentages was made to corroborate this. Based on the aforementioned results, it is concluded that by using the technique developed by Lamendin et al., Very favorable results can be obtained and of great help for the identification of the age of a corpse, which could speed up the recognition of the individual; and above all, applicable to the Salvadoran population.


Asunto(s)
Medicina Legal , El Salvador , Odontología Forense
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