3,559 research outputs found
Sistema de Informacion que Utiliza Datos del Proceso de Fabricacion de un Controlador Logico Programable
En la actualidad, las empresas requieren de la obtención de datos precisos, análisis que apoye en la toma de decisiones y en la mejora continua; estos procesos han llegado a formar parte de la visión de negocios de la gerencia empresarial sobre la cual están orientados los objetivos de negocios para poder ser y permanecer competitivos. Las empresas de manufactura tienen la necesidad de obtener y analizar datos relacionados a los procesos de producción para determinar el nivel de eficiencia de estos y en base a la información obtenida tomar decisiones que ayuden a la empresa a mejorar o corregir situaciones que puedan ser de carácter humano, operativo, procedural o de equipo. En este proyecto de desarrollo de software se ha diseñado e implementado un sistema de información, con el método de cascada, para una empresa de manufactura localizada en la frontera norte de México con Estados Unidos en el sector del cuidado de la salud; el sistema utiliza datos desde un controlador lógico programable, en el cual se obtienen datos para su monitoreo como: alarmas de la máquina, conteo de eventos, duración de cada alarma y velocidad de producción. Dando como resultado información de los códigos de producción, turno, día y hora; además de medir de forma precisa la eficiencia de la máquina, así como la detección de tendencias y la creación de alertas oportunas hacia personas técnicas para la solución de problemas. El sistema consta de un análisis de velocidad y carga de trabajo del procesador del PLC, desarrollo de la conexión entre el procesador y el sistema, preparación del sistema para el traspaso de información, programación de la base de datos en Access y el diseño de la interfaz gráfica en Visual Basic. Net. Entre los logros más importantes obtenidos de la implementación del sistema de información se encuentran: Disponibilidad de la información en tiempo real y obtención de datos históricos de las variables de producción del equipo, mejoramiento de las tareas de supervisión y control de procesos, así como el envío de alertas a usuarios específicos para reacción adecuada a eventos de fallas.
Currently, companies require obtaining accurate data, analysis that supports decision-making and continuous improvement; these processes have become part of the business management vision on which business objectives are oriented to be and remain competitive. Manufacturing companies have the need to obtain and analyze data related to production processes to determine their level of efficiency and based on the information obtained, make decisions that help the company improve or correct situations that may be of human, operational, procedural or equipment. In this software development project, with the cascade method, an information system has been designed and implemented, for a manufacturing company located on the northern border of Mexico with the United States in the health care sector; the system uses data from a programmable logic controller, in which data such as: machine alarms, event count, duration of each alarm, and production speed were obtained for monitoring. Resulting in information on the production codes, shift, day and hour; in addition to accurately measuring the efficiency of the machine, as well as the detection of trends and the creation of timely alerts to technical personnel for troubleshooting. The system consists of an analysis of the speed and workload of the PLC processor, development of the connection between the processor and the system, preparation of the system for the transfer of information, programming of the database and the design of a graphical interface in Visual Basic.Net . Among the most important achievements obtained from the implementation of the information system are: Availability of information in real time and obtaining historical data from production variables, improvement of supervision tasks and process control, as well such as sending alerts to specific users for adequate reaction to failure events
In vitro Validation of Quantitative Light-Induced Fluorescence for the Diagnosis of Enamel Fluorosis in Permanent Teeth
This study aimed to validate quantitative light-induced fluorescence (QLF) as a diagnostic tool for mild and moderate enamel fluorosis in permanent teeth, comparing it to visual diagnosis and histological assessment completed using polarized light microscopy (PLM). The buccal surfaces of 139 teeth were visually classified using the Thylstrup and Fejerskov Index (TFI) into sound (TFI 0; n = 17), mild (TFI 1-2; n = 69), and moderate (TFI 3-4; n = 43) fluorosis. Fluorosis was then assessed with QLF (variables ΔF, A, and ΔQ at 5-, 15-, and 30-radiance thresholds) using as reference areas the entire surface and a region of interest (ROI), identified as the most representative region of a fluorosis lesion. PLM images of longitudinal thin sections including the ROI were assessed for histological changes. Correlations among TFI, PLM, and QLF were determined. A receiver-operating characteristic curve was conducted to determine QLF's diagnostic accuracy when compared to the TFI and PLM assessments. This was used to assess the probability that the images were correctly ranked according to severity as determined by PLM and TFI. A positive correlation was found between QLF and PLM, and between QLF and TFI. QLF showed the highest sensitivity and specificity for the diagnosis of mild fluorosis. There was also a strong agreement between TFI and PLM. The selection of a ROI resulted in a stronger correlation with TFI and PLM than when the entire surface was used. The study results indicate that defining an ROI for QLF assessments is a valid method for the diagnosis of mild and moderate enamel fluorosis
LDL-Induced Impairment of Human Vascular Smooth Muscle Cells Repair Function Is Reversed by HMG-CoA Reductase Inhibition
Growing human atherosclerotic plaques show a progressive loss of vascular smooth muscle cells (VSMC) becoming soft and vulnerable. Lipid loaded-VSMC show impaired vascular repair function and motility due to changes in cytoskeleton proteins involved in cell-migration. Clinical benefits of statins reducing coronary events have been related to repopulation of vulnerable plaques with VSMC. Here, we investigated whether HMG-CoA reductase inhibition with rosuvastatin can reverse the effects induced by atherogenic concentrations of LDL either in the native (nLDL) form or modified by aggregation (agLDL) on human VSMC motility. Using a model of wound repair, we showed that treatment of human coronary VSMC with rosuvastatin significantly prevented (and reversed) the inhibitory effect of nLDL and agLDL in the repair of the cell depleted areas. In addition, rosuvastatin significantly abolished the agLDL-induced dephosphorylation of myosin regulatory light chain as demonstrated by 2DE-electrophoresis and mass spectrometry. Besides, confocal microscopy showed that rosuvastatin enhances actin-cytoskeleton reorganization during lipid-loaded-VSMC attachment and spreading. The effects of rosuvastatin on actin-cytoskeleton dynamics and cell migration were dependent on ROCK-signalling. Furthermore, rosuvastatin caused a significant increase in RhoA-GTP in the cytosol of VSMC. Taken together, our study demonstrated that inhibition of HMG-CoA reductase restores the migratory capacity and repair function of VSMC that is impaired by native and aggregated LDL. This mechanism may contribute to the stabilization of lipid-rich atherosclerotic plaques afforded by statins
Present Status and Future Programs of the n_TOF Experiment
This is an Open Access article distributed under the terms of the Creative Commons Attribution-Noncommercial License 3.0, which permits unrestricted use, distribution, and reproduction in any noncommercial medium, provided the original work is properly citedThe neutron time-of-flight facility n_TOF at CERN, Switzerland, operational since 2001, delivers neutrons using the Proton Synchrotron (PS) 20 GeV/c proton beam impinging on a lead spallation target. The facility combines a very high instantaneous neutron flux, an excellent time of flight resolution due to the distance between the experimental area and the production target (185 meters), a low intrinsic background and a wide range of neutron energies, from thermal to GeV neutrons. These characteristics provide a unique possibility to perform neutron-induced capture and fission cross-section measurements for applications in nuclear astrophysics and in nuclear reactor technology.The most relevant measurements performed up to now and foreseen for the future will be presented in this contribution. The overall efficiency of the experimental program and the range of possible measurements achievable with the construction of a second experimental area (EAR-2), vertically located 20 m on top of the n_TOF spallation target, might offer a substantial improvement in measurement sensitivities. A feasibility study of the possible realisation of the installation extension will be also presented
Anyon in External Electromagnetic Field: Hamiltonian and Lagrangian Formulations
We propose a simple model for a free relativistic particle of fractional spin
in 2+1 dimensions which satisfies all the necessary conditions. The canonical
quantization of the system leads to the description of one- particle states of
the Poincare group with arbitrary spin. Using the Hamil- tonian formulation
with the set of constraints, we introduce the electro- magnetic interaction of
a charged anyon and obtain the Lagrangian. The Casimir operator of the extended
algebra, which is the first-class constraint, is obtained and gives the
equation of motion of the anyon. In particular, from the latter it follows that
the gyromagnetic ratio for a charged anyon is two due to the parallelness of
spin and momentum of the particle in 2+1 dimensions. The canonical quantization
is also considered in this case.Comment: 9 pages, Latex, HU-SEFT R 1993-1
Measurement of the (90,91,92,93,94,96)Zr(n,gamma) and (139)La(n,gamma) cross sections at n_TOF
Open AccessNeutron capture cross sections of Zr and La isotopes have important implications in the field of nuclear astrophysics as well as in the nuclear technology. In particular the Zr isotopes play a key role for the determination of the neutron density in the He burning zone of the Red Giant star, while the (139)La is important to monitor the s-process abundances from Ba up to Ph. Zr is also largely used as structural materials of traditional and advanced nuclear reactors. The nuclear resonance parameters and the cross section of (90,91,92,93,94,96)Zr and (139)La have been measured at the n_TOF facility at CERN. Based on these data the capture resonance strength and the Maxwellian-averaged cross section were calculated
Measurements of high-energy neutron-induced fission of (nat)Pb and (209)Bi
This is an Open Access article distributed under the terms of the Creative Commons Attribution-Noncommercial License 3.0, which permits unrestricted use, distribution, and reproduction in any noncommercial medium, provided the original work is properly citedThe CERN Neutron Time-Of-Flight (n_TOF) facility is well suited to measure low cross sections as those of neutron-induced fission in subactinides. The cross section ratios of (nat)Pb and (209)Bi relative to (235)U and (238)U were measured using PPAC detectors and a fragment coincidence method that allows us to identify the fission events. The present experiment provides first results for neutron-induced fission up to 1 GeV. Good agreement is found with previous experimental data below 200 MeV. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross sections is close to 1 GeV
Phosphoproteomic analysis of neoadjuvant breast cancer suggests that increased sensitivity to paclitaxel is driven by CDK4 and filamin A
Precision oncology research is challenging outside the contexts of oncogenic addiction and/or targeted therapies. We previously showed that phosphoproteomics is a powerful approach to reveal patient subsets of interest characterized by the activity of a few kinases where the underlying genomics is complex. Here, we conduct a phosphoproteomic screening of samples from HER2-negative female breast cancer receiving neoadjuvant paclitaxel (N = 130), aiming to find candidate biomarkers of paclitaxel sensitivity. Filtering 11 candidate biomarkers through 2 independent patient sets (N= 218) allowed the identification of a subgroup of patients characterized by high levels of CDK4 and filamin-A who had a 90% chance of achieving a pCR in response to paclitaxel. Mechanistically, CDK4 regulates filamin-A transcription, which in turn forms a complex with tubulin and CLIP-170, which elicits increased binding of paclitaxel to microtubules, microtubule acetylation and stabilization, and mitotic catastrophe. Thus, phosphoproteomics allows the identification of explainable factors for predicting response to paclitaxel
Measurement of the neutron capture cross section of the s-only isotope 204Pb from 1 eV to 440 keV
The neutron capture cross section of 204Pb has been measured at the CERN
n_TOF installation with high resolution in the energy range from 1 eV to 440
keV. An R-matrix analysis of the resolved resonance region, between 1 eV and
100 keV, was carried out using the SAMMY code. In the interval between 100 keV
and 440 keV we report the average capture cross section. The background in the
entire neutron energy range could be reliably determined from the measurement
of a 208Pb sample. Other systematic effects in this measurement could be
investigated and precisely corrected by means of detailed Monte Carlo
simulations. We obtain a Maxwellian average capture cross section for 204Pb at
kT=30 keV of 79(3) mb, in agreement with previous experiments. However our
cross section at kT=5 keV is about 35% larger than the values reported so far.
The implications of the new cross section for the s-process abundance
contributions in the Pb/Bi region are discussed.Comment: 8 pages, 3 figures, article submitted to Phys. Rev.
Towards the high-accuracy determination of the 238U fission cross section at the threshold region at CERN - N-TOF
The 238U fission cross section is an international standard beyond 2 MeV where the fission plateau starts. However, due to its importance in fission reactors, this cross-section should be very accurately known also in the threshold region below 2 MeV. The 238U fission cross section has been measured relative to the 235U fission cross section at CERN - n-TOF with different detection systems. These datasets have been collected and suitably combined to increase the counting statistics in the threshold region from about 300 keV up to 3 MeV. The results are compared with other experimental data, evaluated libraries, and the IAEA standards
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