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1.
Sci Data ; 10(1): 5, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596792

RESUMO

Multiparametric video-cabled marine observatories are becoming strategic to monitor remotely and in real-time the marine ecosystem. Those platforms can achieve continuous, high-frequency and long-lasting image data sets that require automation in order to extract biological time series. The OBSEA, located at 4 km from Vilanova i la Geltrú at 20 m depth, was used to produce coastal fish time series continuously over the 24-h during 2013-2014. The image content of the photos was extracted via tagging, resulting in 69917 fish tags of 30 taxa identified. We also provided a meteorological and oceanographic dataset filtered by a quality control procedure to define real-world conditions affecting image quality. The tagged fish dataset can be of great importance to develop Artificial Intelligence routines for the automated identification and classification of fishes in extensive time-lapse image sets.


Assuntos
Inteligência Artificial , Ecossistema , Peixes , Animais , Algoritmos , Benchmarking
2.
Sensors (Basel) ; 18(4)2018 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-29642479

RESUMO

An anchored marine seismometer, acquiring real-time seismic data, has been built and tested. The system consists of an underwater seismometer, a surface buoy, and a mooring line that connects them. Inductive communication through the mooring line provides an inexpensive, reliable, and flexible solution. Prior to the deployment the dynamics of the system have been simulated numerically in order to find optimal materials, cables, buoys, and connections under critical marine conditions. The seismometer used is a high sensitivity triaxial broadband geophone able to measure low vibrational signals produced by the underwater seismic events. The power to operate the surface buoy is provided by solar panels. Additional batteries are needed for the underwater unit. In this paper we also present the first results and an earthquake detection of a prototype system that demonstrates the feasibility of this concept. The seismometer transmits continuous data at a rate of 1000 bps to a controller equipped with a radio link in the surface buoy. A GPS receiver on the surface buoy has been configured to perform accurate timestamps on the seismic data, which makes it possible to integrate the seismic data from these marine seismometers into the existing seismic network.

3.
Sensors (Basel) ; 17(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244732

RESUMO

The study of global phenomena requires the combination of a considerable amount of data coming from different sources, acquired by different observation platforms and managed by institutions working in different scientific fields. Merging this data to provide extensive and complete data sets to monitor the long-term, global changes of our oceans is a major challenge. The data acquisition and data archival procedures usually vary significantly depending on the acquisition platform. This lack of standardization ultimately leads to information silos, preventing the data to be effectively shared across different scientific communities. In the past years, important steps have been taken in order to improve both standardization and interoperability, such as the Open Geospatial Consortium's Sensor Web Enablement (SWE) framework. Within this framework, standardized models and interfaces to archive, access and visualize the data from heterogeneous sensor resources have been proposed. However, due to the wide variety of software and hardware architectures presented by marine sensors and marine observation platforms, there is still a lack of uniform procedures to integrate sensors into existing SWE-based data infrastructures. In this work, a framework aimed to enable sensor plug and play integration into existing SWE-based data infrastructures is presented. First, an analysis of the operations required to automatically identify, configure and operate a sensor are analysed. Then, the metadata required for these operations is structured in a standard way. Afterwards, a modular, plug and play, SWE-based acquisition chain is proposed. Finally different use cases for this framework are presented.

4.
Sensors (Basel) ; 15(8): 20436-62, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26295394

RESUMO

This paper describes the development of a low-cost multiparameter acquisition system for volcanic monitoring that is applicable to gravimetry and geodesy, as well as to the visual monitoring of volcanic activity. The acquisition system was developed using a System on a Chip (SoC) Broadcom BCM2835 Linux operating system (based on DebianTM) that allows for the construction of a complete monitoring system offering multiple possibilities for storage, data-processing, configuration, and the real-time monitoring of volcanic activity. This multiparametric acquisition system was developed with a software environment, as well as with different hardware modules designed for each parameter to be monitored. The device presented here has been used and validated under different scenarios for monitoring ocean tides, ground deformation, and gravity, as well as for monitoring with images the island of Tenerife and ground deformation on the island of El Hierro.

5.
Sensors (Basel) ; 12(3): 3693-719, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22737032

RESUMO

The Ocean Bottom Seismometer (OBS) is a key instrument for the geophysical study of sea sub-bottom layers. At present, more reliable autonomous instruments capable of recording underwater for long periods of time and therefore handling large data storage are needed. This paper presents a new Ocean Bottom Seismometer designed to be used in long duration seismic surveys. Power consumption and noise level of the acquisition system are the key points to optimize the autonomy and the data quality. To achieve our goals, a new low power data logger with high resolution and Signal-to-Noise Ratio (SNR) based on Compact Flash memory card is designed to enable continuous data acquisition. The equipment represents the achievement of joint work from different scientific and technological disciplines as electronics, mechanics, acoustics, communications, information technology, marine geophysics, etc. This easy to handle and sophisticated equipment allows the recording of useful controlled source and passive seismic data, as well as other time varying data, with multiple applications in marine environment research. We have been working on a series of prototypes for ten years to improve many of the aspects that make the equipment easy to handle and useful to work in deep-water areas. Ocean Bottom Seismometers (OBS) have received growing attention from the geoscience community during the last forty years. OBS sensors recording motion of the ocean floor hold key information in order to study offshore seismicity and to explore the Earth's crust. In a seismic survey, a series of OBSs are placed on the seabed of the area under study, where they record either natural seismic activity or acoustic signals generated by compressed air-guns on the ocean surface. The resulting data sets are subsequently used to model both the earthquake locations and the crustal structure.

6.
Sensors (Basel) ; 11(6): 5850-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163931

RESUMO

A suitable sampling technology to identify species and to estimate population dynamics based on individual counts at different temporal levels in relation to habitat variations is increasingly important for fishery management and biodiversity studies. In the past two decades, as interest in exploring the oceans for valuable resources and in protecting these resources from overexploitation have grown, the number of cabled (permanent) submarine multiparametric platforms with video stations has increased. Prior to the development of seafloor observatories, the majority of autonomous stations were battery powered and stored data locally. The recently installed low-cost, multiparametric, expandable, cabled coastal Seafloor Observatory (OBSEA), located 4 km off of Vilanova i la Gertrú, Barcelona, at a depth of 20 m, is directly connected to a ground station by a telecommunication cable; thus, it is not affected by the limitations associated with previous observation technologies. OBSEA is part of the European Multidisciplinary Seafloor Observatory (EMSO) infrastructure, and its activities are included among the Network of Excellence of the European Seas Observatory NETwork (ESONET). OBSEA enables remote, long-term, and continuous surveys of the local ecosystem by acquiring synchronous multiparametric habitat data and bio-data with the following sensors: Conductivity-Temperature-Depth (CTD) sensors for salinity, temperature, and pressure; Acoustic Doppler Current Profilers (ADCP) for current speed and direction, including a turbidity meter and a fluorometer (for the determination of chlorophyll concentration); a hydrophone; a seismometer; and finally, a video camera for automated image analysis in relation to species classification and tracking. Images can be monitored in real time, and all data can be stored for future studies. In this article, the various components of OBSEA are described, including its hardware (the sensors and the network of marine and land nodes), software (data acquisition, transmission, processing, and storage), and multiparametric measurement (habitat and bio-data time series) capabilities. A one-month multiparametric survey of habitat parameters was conducted during 2009 and 2010 to demonstrate these functions. An automated video image analysis protocol was also developed for fish counting in the water column, a method that can be used with cabled coastal observatories working with still images. Finally, bio-data time series were coupled with data from other oceanographic sensors to demonstrate the utility of OBSEA in studies of ecosystem dynamics.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Animais , Automação , Biodiversidade , Clorofila/análise , Efeito Doppler , Europa (Continente) , Peixes , Fluorometria/métodos , Geografia , Biologia Marinha/métodos , Oceanografia/métodos , Oceanos e Mares , Dinâmica Populacional , Telecomunicações , Fatores de Tempo , Gravação em Vídeo
7.
Can J Surg ; 47(2): 104-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15132463

RESUMO

INTRODUCTION: The Canadian Task Force on Preventive Health Care (CTF-PHC) recently revised its screening recommendations for colorectal cancer (CRC). We wished to assess the effect of this change on the screening beliefs and clinical practice of primary care physicians. METHODS: We surveyed 160 primary-care physicians, quasi-randomly sampled, in June-July 2001 and again in April-July 2002, 9 months after publication of the guidelines. Descriptive statistics and McNemar chi2 analyses were carried out on data from physicians who responded to both surveys. RESULTS: Of the those sampled, 47% responded to both surveys. After the publication of the CTF-PHC guidelines, the proportion reporting that they recommend CRC screening to their patients at average risk increased from 43% to 60% (p = 0.02). Before publication of the revised guidelines 48% stated that the CTF-PHC did not support screening, compared with 24% afterward (p = 0.01). CTF-PHC guidelines were acknowledged by 30% to be a source of CRC screening information. Around 9 months post-publication, 24% of the physicians stated their awareness of the revised screening guidelines. The most commonly cited reasons for not recommending CRC screening to average-risk patients were that the evidence is inconclusive and that CTF-PHC guidelines do not support screening. CONCLUSIONS: After publication of the revised CTF-PHC guidelines more primary-care physicians reported that they recommend CRC screening to their average-risk patients. The belief that the evidence is inconclusive nevertheless remains a considerable barrier to implementation. To increase the use of screening for CRC, additional strategies are required.


Assuntos
Competência Clínica , Neoplasias Colorretais/diagnóstico , Programas de Rastreamento/normas , Médicos de Família , Guias de Prática Clínica como Assunto , Adulto , Idoso , Atitude do Pessoal de Saúde , Canadá , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Médicos de Família/psicologia , Padrões de Prática Médica , Distribuição Aleatória , Inquéritos e Questionários
8.
Nat Genet ; 31(4): 349-53, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12042820

RESUMO

Identifying the genes involved in polygenic traits has been difficult. In the 1950s and 1960s, laboratory selection experiments for extreme geotaxic behavior in fruit flies established for the first time that a complex behavioral trait has a genetic basis. But the specific genes responsible for the behavior have never been identified using this classical model. To identify the individual genes involved in geotaxic response, we used cDNA microarrays to identify candidate genes and assessed fly lines mutant in these genes for behavioral confirmation. We have thus determined the identities of several genes that contribute to the complex, polygenic behavior of geotaxis.


Assuntos
Comportamento Animal/fisiologia , Drosophila melanogaster/fisiologia , Genética Comportamental/métodos , Mutação , Animais , Animais Geneticamente Modificados , DNA Complementar , Feminino , Análise de Sequência com Séries de Oligonucleotídeos
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