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1.
Microbiol Resour Announc ; : e0034224, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38860812

ABSTRACT

We purified a lytic bacteriophage from soil collected in Guasave, Sinaloa: phiExGM16. This bacteriophage was isolated using the host, Exigoubacterium acetilycum. Its 17.6 kb genome contains 33 putative genes and shows a cover of 64% with 76.37% of nucleotide identity to Microbacterium phage Noelani.

2.
Microbiol Resour Announc ; 13(6): e0030224, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38700345

ABSTRACT

We characterized the complete genome sequence of phiMiGM15, a lytic bacteriophage with siphovirus morphology that infects Microbacterium enclense. Its 48.6 kb genome contains 81 putative genes and shows coverage of 28% with 82.26% of nucleotide identity to Microbacterium phage Caron accession number OQ190481.1.

3.
Sensors (Basel) ; 24(9)2024 May 03.
Article in English | MEDLINE | ID: mdl-38733026

ABSTRACT

In this paper, a six-degree-of-freedom analog tactile probe with a new, simple, and robust mechanical design is presented. Its design is based on the use of one elastomeric ring that supports the stylus carrier and allows its movement inside a cubic measuring range of ±3 mm. The position of the probe tip is determined by three low-cost, noncontact, 2D PSD (position-sensitive detector) sensors, facilitating a wider application of this probe to different measuring systems compared to commercial ones. However, several software corrections, regarding the size and orientation of the three LED light beams, must be carried out when using these 2D sensors for this application due to the lack of additional focusing or collimating lenses and the very wide measuring range. The development process, simulation results, correction models, experimental tests, and calibration of this probe are presented. The results demonstrate high repeatability along the X-, Y-, and Z-axes (2.0 µm, 2.0 µm, and 2.1 µm, respectively) and overall accuracies of 6.7 µm, 7.0 µm, and 8.0 µm, respectively, which could be minimized by more complex correction models.

4.
Rev Alerg Mex ; 69 Suppl 1: s38-s45, 2022.
Article in Spanish | MEDLINE | ID: mdl-34998309

ABSTRACT

Pollen-food syndrome (PFS) is characterized by allergic sensitization to proteins of pollens of grasses, weeds, and trees, which produce a type I hypersensitivity reaction that is associated with the intake of plant-derived foods that are usually in raw form. The most frequently-associated protein families are: profilins, PR-10, and ns LTP; however, others such as thaumatins, isoflavones, reductases, and B1,2 glucanases have been documented. The prototype syndrome is birch-fruit-vegetables, and of these, the most common is birch-apple due to the fact that more than 70 % of patients who are sensitized to birch present symptoms associated with the intake of plant-derived foods. The symptoms are restricted to the oral cavity; however, some patients may present systemic symptoms, including anaphylaxis, so it is important to identify the type of protein that is involved since the type of reaction that the patient may present depends on that. In spite of everything, it is considered an entity that may be under diagnosed due to its complex diagnosis and treatment, since the procedure, in most cases, is an elimination diet, because treatment with immunotherapy is not yet available. The purpose of this review is to describe the pathophysiology, as well as the most common pollen-food syndromes.


El síndrome polen-alimento (SPA) se caracteriza por la sensibilización alérgica a proteínas de pólenes de pastos, malezas y árboles, que producen una reacción de hipersensibilidad de tipo I, asociada a la ingesta de alimentos derivados de plantas, usualmente en forma cruda. Las familias de proteínas que más frecuentemente están asociadas son las profilinas, las PR-10 y las ns LTP; sin embargo, se ha documentado otras, como las taumatinas, isoflavonas reductasas y las B1,2 gluconasas. El síndrome prototipo es el abedul-frutas-vegetales, y de ellos el más común es el abedul-manzana, debido a que más de 70 % de los pacientes sensibilizados al abedul presentan síntomas asociados a la ingesta de alimentos derivados de plantas. Los síntomas están restringidos a la cavidad oral; sin embargo, algunos pacientes pueden presentar síntomas sistémicos, incluso anafilaxia, por lo que es importante identificar el tipo de proteína implicada, ya que de eso depende el tipo de reacción que puede presentar el paciente. Pese a todo, se considera una entidad que puede estar subdiagnosticada debido a su valoración y tratamiento complejos, debido a que el procedimiento en la mayor parte de los casos es dieta de eliminación, ya que aún no está disponible el tratamiento con inmunoterapia. El objetivo de esta revisión es describir la fisiopatología, así como los síndromes polen-alimento más comunes.


Subject(s)
Food Hypersensitivity , Allergens , Cross Reactions , Food Hypersensitivity/diagnosis , Fruit , Humans , Plant Proteins , Pollen , Skin Tests
5.
Sensors (Basel) ; 21(19)2021 Sep 23.
Article in English | MEDLINE | ID: mdl-34640684

ABSTRACT

This paper covers the design of a new multi-point kinematic coupling specially developed for a high precision multi-telescopic arm measurement system for the volumetric verification of machine tools with linear and/or rotary axes. The multipoint kinematic coupling allows the simultaneous operation of the three telescopic arms that are registered at the same time to a sphere fixed on the machine tool spindle nose. Every coupling provides an accurate multi-point contact to the sphere, avoiding collisions and interferences with the other two multi-point kinematic couplings, and generating repulsion forces among them to ensure the coupling's fingers interlacing along the machine tool x/y/z travels in the verification process. Simulation presents minimal deformation of the kinematic coupling under load, assuring the precision of the sphere-to-sphere distance measurement. Experimental results are provided to show that the multi-point kinematic coupling developed has repeatability values below ±1.2 µm in the application.


Subject(s)
Arm , Biomechanical Phenomena
6.
Sensors (Basel) ; 20(13)2020 Jul 07.
Article in English | MEDLINE | ID: mdl-32646000

ABSTRACT

This paper presents the design of a high precision telescopic system consisting in three lines, with measuring principle based on simultaneous laser multilateration. The system offers the high precision of the interferometer systems and allows the autonomous tracking of a sphere joined to the spindle nose of the machine tool by simultaneous contact of all the lines. The main advantage of the system is that it allows data capture to be carried out in a single cycle thanks to simultaneous operation with at least three telescopic arms using a novel multipoint kinematic coupling. This results in a significant reduction of the time taken for data capture and improves measurement accuracy due to avoiding the effect of temperature variations between cycles and machine tool repeatability. The work explains the working principle of the system, its main components, and the design parameters considered for the development of the system. The system is simple to operate, compact, agile, and suitable for the verification of small- or medium-sized machine tools with linear and/or rotary axes.

7.
Materials (Basel) ; 12(23)2019 Nov 29.
Article in English | MEDLINE | ID: mdl-31795339

ABSTRACT

Due to accuracy requirements, robots and machine-tools need to be periodically verified and calibrated through associated verification systems that sometimes use extensible guidance systems. This work presents the development of a reference artefact to evaluate the performance characteristics of different extensible precision guidance systems applicable to robot and machine tool verification. To this end, we present the design, modeling, manufacture and experimental validation of a reference artefact to evaluate the behavior of these extensible guidance systems. The system should be compatible with customized designed guides, as well as with commercial and existing telescopic guidance systems. Different design proposals are evaluated with finite element analysis, and two final prototypes are experimentally tested assuring that the design performs the expected function. An estimation of the uncertainty of the reference artefact is evaluated with a Monte Carlo simulation.

8.
Viruses ; 11(7)2019 06 29.
Article in English | MEDLINE | ID: mdl-31261973

ABSTRACT

Plant DNA viruses of the genus Begomovirus have been documented as the most genetically diverse in the family Geminiviridae and present a serious threat for global horticultural production, especially considering climate change. It is important to characterize naturally existing begomoviruses, since viral genetic diversity in non-cultivated plants could lead to future disease epidemics in crops. In this study, high-throughput sequencing (HTS) was employed to determine viral diversity of samples collected in a survey performed during 2012-2016 in seven states of Northern-Pacific Mexico, areas of diverse climatic conditions where different vegetable crops are subject to intensive farming. In total, 132 plant species, belonging to 34 families, were identified and sampled in the natural ecosystems surrounding cultivated areas (agro-ecological interface). HTS analysis and subsequent de novo assembly revealed a number of geminivirus-related DNA signatures with 80 to 100% DNA similarity with begomoviral sequences present in the genome databank. The analysis revealed DNA signatures corresponding to 52 crop-infecting and 35 non-cultivated-infecting geminiviruses that, interestingly, were present in different plant species. Such an analysis deepens our knowledge of geminiviral diversity and could help detecting emerging viruses affecting crops in different agro-climatic regions.


Subject(s)
Begomovirus/isolation & purification , Biodiversity , Crops, Agricultural/virology , Plant Diseases/virology , Plant Viruses/isolation & purification , Begomovirus/classification , Begomovirus/genetics , Crops, Agricultural/growth & development , High-Throughput Nucleotide Sequencing , Mexico , Phylogeny , Plant Viruses/classification , Plant Viruses/genetics
9.
Materials (Basel) ; 11(8)2018 Aug 07.
Article in English | MEDLINE | ID: mdl-30087250

ABSTRACT

Tapered roller bearings can accommodate high radial loads as well as high axial loads. The manufacturing process consists of machining processes for ring and component assembly. In this contribution, the parameters of influence on the measurement procedure were studied. These parameters of influence were classified as environmental, process, and machine parameters. The main objective of this work was to optimize the process using real-time measurements, which required the study of the influence of several parameters on the measurement uncertainty and how to correct their effects.

10.
Sensors (Basel) ; 16(1)2016 Jan 11.
Article in English | MEDLINE | ID: mdl-26761014

ABSTRACT

Both an accurate machine design and an adequate metrology loop definition are critical factors when precision positioning represents a key issue for the final system performance. This article discusses the error budget methodology as an advantageous technique to improve the measurement accuracy of a 2D-long range stage during its design phase. The nanopositioning platform NanoPla is here presented. Its specifications, e.g., XY-travel range of 50 mm × 50 mm and sub-micrometric accuracy; and some novel designed solutions, e.g., a three-layer and two-stage architecture are described. Once defined the prototype, an error analysis is performed to propose improvement design features. Then, the metrology loop of the system is mathematically modelled to define the propagation of the different sources. Several simplifications and design hypothesis are justified and validated, including the assumption of rigid body behavior, which is demonstrated after a finite element analysis verification. The different error sources and their estimated contributions are enumerated in order to conclude with the final error values obtained from the error budget. The measurement deviations obtained demonstrate the important influence of the working environmental conditions, the flatness error of the plane mirror reflectors and the accurate manufacture and assembly of the components forming the metrological loop. Thus, a temperature control of ±0.1 °C results in an acceptable maximum positioning error for the developed NanoPla stage, i.e., 41 nm, 36 nm and 48 nm in X-, Y- and Z-axis, respectively.

11.
ScientificWorldJournal ; 2014: 959510, 2014.
Article in English | MEDLINE | ID: mdl-25202744

ABSTRACT

This paper aims to present a method of volumetric verification in machine tools with linear and rotary axes using a laser tracker. Beyond a method for a particular machine, it presents a methodology that can be used in any machine type. Along this paper, the schema and kinematic model of a machine with three axes of movement, two linear and one rotational axes, including the measurement system and the nominal rotation matrix of the rotational axis are presented. Using this, the machine tool volumetric error is obtained and nonlinear optimization techniques are employed to improve the accuracy of the machine tool. The verification provides a mathematical, not physical, compensation, in less time than other methods of verification by means of the indirect measurement of geometric errors of the machine from the linear and rotary axes. This paper presents an extensive study about the appropriateness and drawbacks of the regression function employed depending on the types of movement of the axes of any machine. In the same way, strengths and weaknesses of measurement methods and optimization techniques depending on the space available to place the measurement system are presented. These studies provide the most appropriate strategies to verify each machine tool taking into consideration its configuration and its available work space.


Subject(s)
Models, Theoretical , Algorithms
12.
Sensors (Basel) ; 11(1): 90-110, 2011.
Article in English | MEDLINE | ID: mdl-22346569

ABSTRACT

This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly "coupled" as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a "zero" or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy.


Subject(s)
Lasers , Robotics , Automation , Optical Devices
13.
s.l; UPCH. Facultad de Medicina Alberto Hurtado; 1992. 54 p. tab. (PE-3271-3271a).
Thesis in Spanish | LILACS | ID: lil-107465

ABSTRACT

El consumo de medicamentos previo a una consulta hospitalaria es un hecho frecuente. Para determinar la magnitud de éste hecho en pacientes pediatricos que acuden a la emergencia y determinar que factores lo favorecen, se ralizó un estudio transversal, tipo encuesta, a los familiares de los pacientes que acudieron a la emergencia pediatrica de dos hospitales de Lima metropolitana. De 187 pacientes, se encontró que 130 (69.5 por ciento) habían recibido algún medicamento antes de la consulta y que 113 (86.9 por ciento) de éstos lo hicieron por automedicación. Los factores que favorecen éste hecho son el ser menor de un año y mayor de cinco años, y el hecho de tener un hermano mayor. Los grupos de medicamentos mas consumidos fueron el de los antipiréticos, los antibióticos y los broncodilatadores. de los medicamentos consumidos, el 42.4 por ciento no eran los adecuados para la enfermedad y el 48.6 por ciento de las dosis usadas fueron inadecuadas. Se concluye que el consumo de medicamentos previo a la consulta pediatrica es un hecho frecuente, siendo en casi la mitad de los casos inadecuado, tanto en la elección como en la dosis usada


Subject(s)
Humans , Infant, Newborn , Infant , Child, Preschool , Self Medication/statistics & numerical data , Emergencies , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Anti-Bacterial Agents/therapeutic use , Bronchodilator Agents/therapeutic use , Cross-Sectional Studies , Nonprescription Drugs , Peru
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