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1.
Rev Esp Enferm Dig ; 113(1): 71, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33054290

ABSTRACT

Appendicular invagination is a rare situation, with an incidence of 0.01 %. The clinical presentation can be variable from acute appendicitis to chronic abdominal pain, intestinal obstruction by intussusception or simply appear as a radiologic or intraoperative finding. Endometriosis is the underlying cause of appendicular invagination in one-third of cases but the possibility of neoplastic pathology should always be considered in these cases.


Subject(s)
Appendicitis , Appendix , Endometriosis , Intestinal Obstruction , Intussusception , Appendix/diagnostic imaging , Appendix/surgery , Endometriosis/complications , Endometriosis/diagnostic imaging , Endometriosis/surgery , Female , Humans , Intestinal Obstruction/diagnostic imaging , Intestinal Obstruction/etiology , Intestinal Obstruction/surgery , Intussusception/diagnostic imaging , Intussusception/etiology , Intussusception/surgery
2.
Sensors (Basel) ; 20(11)2020 Jun 02.
Article in English | MEDLINE | ID: mdl-32498405

ABSTRACT

This paper expands upon a previous publication and is the natural continuation of an earlier study which presented an industrial validator of expiration codes printed on aluminium or tin cans, called MONICOD. MONICOD is distinguished by its high operating speed, running at 200 frames per second and validating up to 35 cans per second. This paper adds further detail to this description by describing the final stage of the MONICOD industrial validator: the process of effectively validating the characters. In this process we compare the acquired shapes, segmented during the prior stages, with expected character shapes. To do this, we use a template matching scheme (here called "morphologies") based on bitwise operations. Two learning algorithms for building the valid morphology databases are also presented. The results of the study presented here show that in the acquisition of 9885 frames containing 465 cans to be validated, there was only one false positive (0.21% of the total). Another notable feature is that it is at least 20% faster in validation time with error rates similar to those of classifiers such as support vector machines (SVM), radial base functions (RBF), multi-layer perceptron with backpropagation (MLP) and k-nearest neighbours (KNN).

3.
Sensors (Basel) ; 19(14)2019 Jul 12.
Article in English | MEDLINE | ID: mdl-31336953

ABSTRACT

Indoor positioning systems (IPS) are used to locate people or objects in environments where the global positioning system (GPS) fails. The commitment to make bluetooth low energy (BLE) technology the leader in IPS and their applications is clear: Since 2009, the Bluetooth Special Interest Group (SIG) has released several improved versions. BLE offers many advantages for IPS, e.g., their emitters or beacons are easily deployable, have low power consumption, give a high positioning accuracy and can provide advanced services to users. Fingerprinting is a popular indoor positioning algorithm that is based on the received signal strength (RSS); however, its main drawbacks are that data collection is a time-consuming and labor-intensive process and its main challenge is that positioning accuracy is affected by various factors. The purpose of this work was to develop a semi-automatic data collection support system in a BLE fingerprinting-based IPS to: (1) Streamline and shorten the data collection process, (2) carry out impact studies by protocol and channel on the static positioning accuracy related to configuration parameters of the beacons, such as transmission power (Tx) and the advertising interval (A), and their number and geometric distribution. With two types of systems-on-chip (SoCs) integrated in Bluetooth 5 beacons and in two different environments, our results showed that on average in the three BLE advertising channels, the configuration of the highest Tx (+4 dBm) in the beacons produced the best accuracy results. However, the lowest Tx (-20 dBm) did not worsen them excessively (only 11.8%). In addition, in both scenarios, when lowering the density of beacons by around 42.7%-50%, the error increase was only around 8%-9.2%.

4.
Sensors (Basel) ; 19(13)2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31261640

ABSTRACT

In road-based mass transit systems, travel time is a key factor in providing quality of service. This article proposes a method of predicting travel time for this type of transport system. This method estimates travel time by taking into account its historical behaviour, represented by historical profiles, and the current behaviour recorded on the public transport vehicle for which the prediction is to be made. The model uses the k-medoids clustering algorithm to obtain historical travel time profiles. A relevant feature of the model is that it does not require recent travel time data from other vehicles. For this reason, the proposed model may be used in intercity transport contexts in which service planning is carried out according to timetables. The proposed model has been tested with two real cases of intercity public transport routes and from the results obtained we may conclude that, in general, the average error of the predictions is around 13% compared to the observed travel time values.

5.
Entropy (Basel) ; 20(2)2018 Feb 20.
Article in English | MEDLINE | ID: mdl-33265224

ABSTRACT

The development of efficient mass transit systems that provide quality of service is a major challenge for modern societies. To meet this challenge, it is essential to understand user demand. This article proposes using new time-dependent attributes to represent demand, attributes that differ from those that have traditionally been used in the design and planning of this type of transit system. Data mining was used to obtain these new attributes; they were created using clustering techniques, and their quality evaluated with the Shannon entropy function and with neural networks. The methodology was implemented on an intercity public transport company and the results demonstrate that the attributes obtained offer a more precise understanding of demand and enable predictions to be made with acceptable precision.

6.
Sensors (Basel) ; 17(6)2017 Jun 16.
Article in English | MEDLINE | ID: mdl-28621745

ABSTRACT

Quality is an essential aspect of public transport. In the case of regular public passenger transport by road, punctuality and regularity are criteria used to assess quality of service. Calculating metrics related to these criteria continuously over time and comprehensively across the entire transport network requires the handling of large amounts of data. This article describes a system for continuously and comprehensively monitoring punctuality and regularity. The system uses location data acquired continuously in the vehicles and automatically transferred for analysis. These data are processed intelligently by elements that are commonly used by transport operators: GPS-based tracking system, onboard computer and wireless networks for mobile data communications. The system was tested on a transport company, for which we measured the punctuality of one of the routes that it operates; the results are presented in this article.

7.
Sensors (Basel) ; 17(6)2017 Jun 06.
Article in English | MEDLINE | ID: mdl-28587285

ABSTRACT

This paper presents a study of positioning system that provides advanced information services based on Wi-Fi and Bluetooth Low Energy (BLE) technologies. It uses Wi-Fi for rough positioning and BLE for fine positioning. It is designed for use in public transportation system stations and terminals where the conditions are "hostile" or unfavourable due to signal noise produced by the continuous movement of passengers and buses, data collection conducted in the constant presence thereof, multipath fading, non-line of sight (NLOS) conditions, the fact that part of the wireless communication infrastructure has already been deployed and positioned in a way that may not be optimal for positioning purposes, variable humidity conditions, etc. The ultimate goal is to provide a service that may be used to assist people with special needs. We present experimental results based on scene analysis; the main distance metric used was the Euclidean distance but the Mahalanobis distance was also used in one case. The algorithm employed to compare fingerprints was the weighted k-nearest neighbor one. For Wi-Fi, with only three visible access points, accuracy ranged from 3.94 to 4.82 m, and precision from 5.21 to 7.0 m 90% of the time. With respect to BLE, with a low beacon density (1 beacon per 45.7 m²), accuracy ranged from 1.47 to 2.15 m, and precision from 1.81 to 3.58 m 90% of the time. Taking into account the fact that this system is designed to work in real situations in a scenario with high environmental fluctuations, and comparing the results with others obtained in laboratory scenarios, our results are promising and demonstrate that the system would be able to position users with these reasonable values of accuracy and precision.

8.
Sensors (Basel) ; 16(4)2016 Apr 13.
Article in English | MEDLINE | ID: mdl-27089340

ABSTRACT

Expiration date labels are ubiquitous in the food industry. With the passage of time, almost any food becomes unhealthy, even when well preserved. The expiration date is estimated based on the type and manufacture/packaging time of that particular food unit. This date is then printed on the container so it is available to the end user at the time of consumption. MONICOD (MONItoring of CODes); an industrial validator of expiration codes; allows the expiration code printed on a drink can to be read. This verification occurs immediately after printing. MONICOD faces difficulties due to the high printing rate (35 cans per second) and problematic lighting caused by the metallic surface on which the code is printed. This article describes a solution that allows MONICOD to extract shapes and presents quantitative results for the speed and quality.

9.
Sensors (Basel) ; 16(7)2016 Jul 16.
Article in English | MEDLINE | ID: mdl-27438836

ABSTRACT

This paper presents an architecture model for the development of intelligent systems for public passenger transport by road. The main objective of our proposal is to provide a framework for the systematic development and deployment of telematics systems to improve various aspects of this type of transport, such as efficiency, accessibility and safety. The architecture model presented herein is based on international standards on intelligent transport system architectures, ubiquitous computing and service-oriented architecture for distributed systems. To illustrate the utility of the model, we also present a use case of a monitoring system for stops on a public passenger road transport network.

10.
Sensors (Basel) ; 16(6)2016 Jun 21.
Article in English | MEDLINE | ID: mdl-27338397

ABSTRACT

In this article we describe a low-cost, minimally-intrusive system for the efficient management of parking spaces on both public roads and controlled zones. This system is based on wireless networks of photoelectric sensors that are deployed on the access roads into and out of these areas. The sensors detect the passage of vehicles on these roads and communicate this information to a data centre, thus making it possible to know the number of vehicles in the controlled zone and the occupancy levels in real-time. This information may be communicated to drivers to facilitate their search for a parking space and to authorities so that they may take steps to control traffic when congestion is detected.

11.
Sensors (Basel) ; 15(8): 20279-304, 2015 Aug 18.
Article in English | MEDLINE | ID: mdl-26295234

ABSTRACT

The development of public transit systems that are accessible and safe for everyone, including people with special needs, is an objective that is justified from the civic and economic points of view. Unfortunately, public transit services are conceived for people who do not have reduced physical or cognitive abilities. In this paper, we present an intelligent public transit system by highway with the goal of facilitating access and improving the safety of public transit for persons with special needs. The system is deployed using components that are commonly available in transport infrastructure, e.g., sensors, mobile communications systems, and positioning systems. In addition, the system can operate in non-urban transport contexts, e.g., isolated rural areas, where the availability of basic infrastructure, such as electricity and communications infrastructures, is not always guaranteed. To construct the system, the principles and techniques of Ubiquitous Computing and Ambient Intelligence have been employed. To illustrate the utility of the system, two cases of services rendered by the system are described: the first case involves a surveillance system to guarantee accessibility at bus stops; the second case involves a route assistant for blind people.

12.
Sensors (Basel) ; 14(4): 7342-58, 2014 Apr 23.
Article in English | MEDLINE | ID: mdl-24763212

ABSTRACT

This study describes a system for the automatic recording of positioning data for public transport vehicles used on roads. With the data provided by this system, transportation-regulatory authorities can control, verify and improve the routes that vehicles use, while also providing new data to improve the representation of the transportation network and providing new services in the context of intelligent metropolitan areas. The system is executed autonomously in the vehicles, by recording their massive positioning data and transferring them to remote data banks for subsequent processing. To illustrate the utility of the system, we present a case of application that consists of identifying the points at which vehicles stop systematically, which may be points of scheduled stops or points at which traffic signals or road topology force the vehicle to stop. This identification is performed using pattern recognition techniques. The system has been applied under real operating conditions, providing the results discussed in the present study.


Subject(s)
Geographic Information Systems , Motor Vehicles , Transportation , Cluster Analysis , Geography
13.
J Ambient Intell Humaniz Comput ; 14(7): 9253-9275, 2023.
Article in English | MEDLINE | ID: mdl-36212894

ABSTRACT

Millions of people use public transport systems daily, hence their interest for the epidemiology of respiratory infectious diseases, both from a scientific and a health control point of view. This article presents a methodology for obtaining epidemiological information on these types of diseases in the context of a public road transport system. This epidemiological information is based on an estimation of interactions with risk of infection between users of the public transport system. The methodology is novel in its aim since, to the best of our knowledge, there is no previous study in the context of epidemiology and public transport systems that addresses this challenge. The information is obtained by mining the data generated from trips made by transport users who use contactless cards as a means of payment. Data mining therefore underpins the methodology. One achievement of the methodology is that it is a comprehensive approach, since, starting from a formalisation of the problem based on epidemiological concepts and the transport activity itself, all the necessary steps to obtain the required epidemiological knowledge are described and implemented. This includes the estimation of data that are generally unknown in the context of public transport systems, but that are required to generate the desired results. The outcome is useful epidemiological data based on a complete and reliable description of all estimated potentially infectious interactions between users of the transport system. The methodology can be implemented using a variety of initial specifications: epidemiological, temporal, geographic, inter alia. Another feature of the methodology is that with the information it provides, epidemiological studies can be carried out involving a large number of people, producing large samples of interactions obtained over long periods of time, thereby making it possible to carry out comparative studies. Moreover, a real use case is described, in which the methodology is applied to a road transport system that annually moves around 20 million passengers, in a period that predates the COVID-19 pandemic. The results have made it possible to identify the group of users most exposed to infection, although they are not the largest group. Finally, it is estimated that the application of a seat allocation strategy that minimises the risk of infection reduces the risk by 50%.

14.
Sci Total Environ ; 892: 164627, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37285999

ABSTRACT

The digital elevation models (DEMs) are the primary and most important spatial inputs for a wide range of hydrological applications. However, their availability from multiple sources and at various spatial resolutions poses a challenge in watershed modeling as they influence hydrological feature delineation and model simulations. In this study, we evaluated the effect of DEM choice on stream and catchment delineation and streamflow simulation using the SWAT model in four distinct geographic regions with diverse terrain surfaces. Performance evaluation metrics, including Willmott's index of agreement, and nRMSE combined with visual comparisons were employed to assess each DEM's performance. Our results revealed that the choice of DEM has a significant impact on the accuracy of stream and catchment delineation, while its influence on streamflow simulation within the same catchment was relatively minor. Among the evaluated DEMs, AW3D30 and COP30 performed the best, closely followed by MERIT, whereas TanDEM-X and HydroSHEDS exhibited poorer performance. All DEMs displayed better accuracy in mountainous and larger catchments compared to smaller and flatter catchments. Forest cover also played a role in accuracy, mainly due to its association with steep slopes. Our findings provide valuable insights for making informed data selection decisions in watershed modeling, considering the specific characteristics of the catchment and the desired level of accuracy.


Subject(s)
Environmental Monitoring , Models, Theoretical , Environmental Monitoring/methods , Rivers , Forests , Hydrology/methods
15.
Tetrahedron Lett ; 53(8): 910-913, 2012 Feb 22.
Article in English | MEDLINE | ID: mdl-22267879

ABSTRACT

New spiroaminoborate esters derived from 1,1-diphenylprolinol, ephedrine and dihydroquinine with different alkoxy substituents were prepared as stable crystalline compounds and characterized by spectroscopical analysis and specific rotation. The structure of the spiroborate 4 derived from 1,1-diphenylprolinol and dicyclohexyl-1,1'-diol was confirmed by X-ray analysis.

16.
Sensors (Basel) ; 12(5): 5290-309, 2012.
Article in English | MEDLINE | ID: mdl-22778585

ABSTRACT

This paper presents OnRoute, a framework for developing and running ubiquitous software that provides information services to passengers of public transportation, including payment systems and on-route guidance services. To achieve a high level of interoperability, accessibility and context awareness, OnRoute uses the ubiquitous computing paradigm. To guarantee the quality of the software produced, the reliable software principles used in critical contexts, such as automotive systems, are also considered by the framework. The main components of its architecture (run-time, system services, software components and development discipline) and how they are deployed in the transportation network (stations and vehicles) are described in this paper. Finally, to illustrate the use of OnRoute, the development of a guidance service for travellers is explained.

17.
Clin Orthop Relat Res ; 468(5): 1214-20, 2010 May.
Article in English | MEDLINE | ID: mdl-20012237

ABSTRACT

BACKGROUND: Better muscular recovery of the extensor mechanism after TKA is claimed by femoral designs based on a sagittal single radius. QUESTIONS/PURPOSES: We aimed to compare postoperative knee performance through the Knee Society scores, flexor and extensor muscle function, stability, and gait of a series of patients receiving a posterior stabilized, cemented TKA, with a single-radius femoral design. METHODS: We compared a series of patients treated with a single-radius femoral design TKA to a simultaneous series of patients receiving a multiradius femoral design. Both groups were similar in demographics and preoperative Knee Society scores. The clinical pathways were identical. Outcome assessment included Knee Society scores, isokinetic assessment, stabilometry, and gait cycle analysis. RESULTS: We observed higher functional Knee Society scores (86.6 +/- 1.89 versus 80.3 +/- 1.90), fewer physiotherapy sessions (19.9 +/- 4.65 versus 22.2 +/- 3.34), and less time with two crutches (3.5 +/- 1.2 versus 5.2 +/- 1.04 weeks) for patients receiving the single-radius design. Isokinetic evaluation showed decreased flexion peak torque (40.3 +/- 7.9 versus 48.7 +/- 9.6), increased extension peak torque (77.2 +/- 16.1 versus 69.1 +/- 14.4), and lower flexor/extensor ratio (0.5 +/- 0.08 versus 0.7 +/- 0.1) in patients with the single-radius design. Stabilometry showing less relative oscillation, and gait cycle indirectly confirmed better support in the limb with the single-radius design. CONCLUSIONS: The studied single-radius femoral design showed better functional short-term outcome and better extensor performance. LEVEL OF EVIDENCE: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.


Subject(s)
Arthroplasty, Replacement, Knee/instrumentation , Knee Joint/physiology , Knee Prosthesis , Osteoarthritis, Knee/surgery , Range of Motion, Articular , Aged , Female , Follow-Up Studies , Gait/physiology , Humans , Male , Osteoarthritis, Knee/physiopathology , Osteoarthritis, Knee/rehabilitation , Prosthesis Design , Recovery of Function/physiology , Retrospective Studies , Treatment Outcome
18.
Photochem Photobiol ; 85(1): 160-70, 2009.
Article in English | MEDLINE | ID: mdl-18673321

ABSTRACT

The mechanisms that trigger the phototoxic response to 2-chlorophenothiazine derivatives are still unknown. To better understand the relationship between the molecular structure of halogenated phenothiazines and their phototoxic activity, their photophysics and photochemistry were studied in several alcohols. The photodestruction quantum yields were determined under anaerobic conditions using monochromatic light (313 nm). Absorption- and emission-spectroscopy, (1)H- and (13)C-NMR and GC-MS were used to characterize the photoproducts and reference compounds. An electron transfer mechanism had been previously proposed by Bunce et al. (J. Med. Chem. 22, 202-204) to explain the large difference between the photodestruction quantum yield of 2-chlorpromazine (phi = 0.46) and 2-chlorphenothiazine (phi = 0.20). According to these authors, the alkylamino chain transfers an electron to the phenothiazine moiety. Our results demonstrate that this mechanism is incorrect, because the photodestruction quantum yields of all chlorinated derivatives of this study are the same under the same conditions of solvent and irradiation wavelength. The quantum yield has no dependence on the 10-substituent, but it depends on the solvent. The percentage of each photoproduct, on the other hand, strongly depends on that substituent, but not very much on the solvent. Finally, it is demonstrated that the phototoxic effect of chlorinated phenothiazines is not related to the photodechlorination, although both processes share the same transient.


Subject(s)
Alcohols/chemistry , Chlorine Compounds/chemistry , Phenothiazines/chemistry , Photolysis , Kinetics , Molecular Structure
19.
Photochem Photobiol ; 85(4): 895-900, 2009.
Article in English | MEDLINE | ID: mdl-19708200

ABSTRACT

Chlorprothixene (CPTX, Taractan) is a low potency antipsychotic mainly used for the treatment of psychotic disorders (e.g. schizophrenia) and acute mania occurring as part of bipolar disorders. As in the case of other numerous drugs used in the treatment of psychiatric disorders, CPTX presents geometric isomerism. Therefore, in vitro irradiation induces a rapid Z/E isomerization, which can affect its pharmacokinetic properties. This photoisomerization is not dependent on the oxygen concentration. The Z/E quantum yields determined for zCPTX in acetonitrile are 0.22 and 0.21 in anaerobic and aerobic environments, respectively. In the presence of water, both isomers decompose to produce 2-chlorothioxanthone (CTX) after prolonged irradiation. This process strongly depends on the water concentration and the irradiation time, i.e. it is autocatalyzed by the CTX through a triplet-energy transfer mechanism. The protonation state of the terminal amino group, on the other hand, has no effect on the isomerization process, but inhibits the formation of CTX. These results indicate that the phototoxicity of zCPTX is somehow affected by the formation of CTX.


Subject(s)
Acetonitriles/chemistry , Antipsychotic Agents/chemistry , Chlorprothixene/chemistry , Photochemistry
20.
Tetrahedron Lett ; 50(9): 995-998, 2009 Mar 04.
Article in English | MEDLINE | ID: mdl-20160845

ABSTRACT

The novel dimethoxyl(aminoalkoxy)borate 1 was isolated as a white crystalline dimer joined by H-bonding as evidenced by X-ray analysis, and demonstrated to be a highly effective catalyst for the asymmetric reduction of representative prochiral ketones with borane-DMS. Optically pure alcohols were obtained using only 1 mol% of catalyst 1 in up to 99% ee.

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