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1.
Sensors (Basel) ; 24(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39000914

RESUMO

The acquisition of the body temperature of animals kept in captivity in biology laboratories is crucial for several studies in the field of animal biology. Traditionally, the acquisition process was carried out manually, which does not guarantee much accuracy or consistency in the acquired data and was painful for the animal. The process was then switched to a semi-manual process using a thermal camera, but it still involved manually clicking on each part of the animal's body every 20 s of the video to obtain temperature values, making it a time-consuming, non-automatic, and difficult process. This project aims to automate this acquisition process through the automatic recognition of parts of a lizard's body, reading the temperature in these parts based on a video taken with two cameras simultaneously: an RGB camera and a thermal camera. The first camera detects the location of the lizard's various body parts using artificial intelligence techniques, and the second camera allows reading of the respective temperature of each part. Due to the lack of lizard datasets, either in the biology laboratory or online, a dataset had to be created from scratch, containing the identification of the lizard and six of its body parts. YOLOv5 was used to detect the lizard and its body parts in RGB images, achieving a precision of 90.00% and a recall of 98.80%. After initial calibration, the RGB and thermal camera images are properly localised, making it possible to know the lizard's position, even when the lizard is at the same temperature as its surrounding environment, through a coordinate conversion from the RGB image to the thermal image. The thermal image has a colour temperature scale with the respective maximum and minimum temperature values, which is used to read each pixel of the thermal image, thus allowing the correct temperature to be read in each part of the lizard.


Assuntos
Inteligência Artificial , Temperatura Corporal , Lagartos , Animais , Lagartos/fisiologia , Temperatura Corporal/fisiologia , Gravação em Vídeo/métodos , Processamento de Imagem Assistida por Computador/métodos
2.
Sensors (Basel) ; 23(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36679621

RESUMO

In this work, a large-scale tactile detection system is proposed, whose development is based on a soft structure using Machine Learning and Computer Vision algorithms to map the surface of a forearm sleeve. The current application has a cylindrical design, whose dimensions intend to be like a human forearm or bicep. The model was developed assuming that deformations occur only at one section at a time. The goal for this system is to be coupled with the CHARMIE robot, a collaborative robot for domestic and medical environments. This system allows the contact detection of the entire forearm surface enabling interaction between a Human Being and a robot. A matrix with sections can be configured to present certain functionalities, allowing CHARMIE to detect contact in a particular section, and thus perform a specific behaviour. After building the dataset, an Artificial Neural Network (ANN) was created. This network was called Section Detection Network (SDN), and through Supervised Learning, a model was created to predict the contact location. Furthermore, Stratified K-Fold Cross Validation (SKFCV) was used to divide the dataset. All these steps resulted in Neural Network with a test data accuracy higher than 80%. Regarding the real-time evaluation, a graphical interface was structured to demonstrate the predicted class and the corresponding probability. This research concluded that the method described has enormous potential to be used as a tool for service robots allowing enhanced human-robot interaction.


Assuntos
Robótica , Humanos , Robótica/métodos , Tato , Redes Neurais de Computação , Algoritmos , Aprendizado de Máquina Supervisionado
3.
Microbiology (Reading) ; 166(2): 149-156, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31860438

RESUMO

Pseudomonas putida is a micro-organism with great potential for industry due to its stress-endurance traits and easy manipulation of the metabolism. However, optimization is still required to improve production yields. In the last years, manipulation of bacterial small non-coding RNAs (ncRNAs) has been recognized as an effective tool to improve the production of industrial compounds. So far, very few ncRNAs are annotated in P. putida beyond the generally conserved. In the present study, P. putida was cultivated in a two-compartment scale-down bioreactor that simulates large-scale industrial bioreactors. We performed RNA-Seq of samples collected at distinct locations and time-points to predict novel and potentially important ncRNAs for the adaptation of P. putida to bioreactor stress conditions. Instead of using a purely genomic approach, we have rather identified regions of putative ncRNAs with high expression levels using two different programs (Artemis and sRNA detect). Only the regions identified with both approaches were considered for further analysis and, in total, 725 novel ncRNAs were predicted. We also found that their expression was not constant throughout the bioreactor, showing different patterns of expression with time and position. This is the first work focusing on the ncRNAs whose expression is triggered in a bioreactor environment. This information is of great importance for industry, since it provides possible targets to engineer more effective P. putida strains for large-scale production.


Assuntos
Reatores Biológicos/microbiologia , Pseudomonas putida/fisiologia , RNA Bacteriano/metabolismo , RNA não Traduzido/metabolismo , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano/genética , Pseudomonas putida/genética , Pseudomonas putida/crescimento & desenvolvimento , Pseudomonas putida/metabolismo , RNA Bacteriano/classificação , RNA Bacteriano/genética , RNA não Traduzido/classificação , RNA não Traduzido/genética , Análise de Sequência de RNA , Estresse Fisiológico
4.
Sensors (Basel) ; 16(4)2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27104535

RESUMO

This paper presents a road surface scanning system that operates with a trichromatic line scan camera with light emitting diode (LED) lighting achieving road surface resolution under a millimeter. It was part of a project named Roadkills-Intelligent systems for surveying mortality of amphibians in Portuguese roads, sponsored by the Portuguese Science and Technology Foundation. A trailer was developed in order to accommodate the complete system with standalone power generation, computer image capture and recording, controlled lighting to operate day or night without disturbance, incremental encoder with 5000 pulses per revolution attached to one of the trailer wheels, under a meter Global Positioning System (GPS) localization, easy to utilize with any vehicle with a trailer towing system and focused on a complete low cost solution. The paper describes the system architecture of the developed prototype, its calibration procedure, the performed experimentation and some obtained results, along with a discussion and comparison with existing systems. Sustained operating trailer speeds of up to 30 km/h are achievable without loss of quality at 4096 pixels' image width (1 m width of road surface) with 250 µm/pixel resolution. Higher scanning speeds can be achieved by lowering the image resolution (120 km/h with 1 mm/pixel). Computer vision algorithms are under development to operate on the captured images in order to automatically detect road-kills of amphibians.

5.
Metabolites ; 9(11)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652780

RESUMO

BolA is a ubiquitous global transcription factor. Despite its clear role in the induction of important stress-resistant physiological changes and its recent implication in the virulence of Salmonella, further research is required to shed light on the pathways modulated by BolA. In this study, we resorted to untargeted 1H-NMR metabolomics to understand the impact of BolA on the metabolic profile of Salmonella Typhimurium, under virulence conditions. Three strains of S. Typhimurium SL1344 were studied: An SL1344 strain transformed with an empty plasmid (control), a bolA knockout mutant (ΔbolA), and a strain overexpressing bolA (bolA+). These strains were grown in a minimal virulence-inducing medium and cells were collected at the end of the exponential and stationary phases. The extracts were analyzed by NMR, and multivariate and univariate statistical analysis were performed to identify significant alterations. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) of 1H-NMR data allowed the discrimination between the metabolic profiles of these strains, revealing increased levels of acetate, valine, alanine, NAD+, succinate, coenzyme A, glutathione, and putrescine in bolA+. These results indicate that BolA regulates pathways related to stress resistance and virulence, being an important modulator of the metabolic processes needed for S. Typhimurium infection.

6.
Mar Environ Res ; 71(1): 53-61, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21047678

RESUMO

A number of studies have suggested that mangrove forests and their faunal components may be pre-adapted to the impact of organic waste discharge, making them possible natural wastewater treatment wetlands. However, the results from recent research are contradictory. Some studies have shown that negative effects, sometimes subtle and difficult to observe, can be detected on specific biotic components of forests subjected to organic pollution. Therefore, the aim of the present study was to investigate possible alterations in the ecosystem engineering activities of a fiddler crab community dominating the landward belts of Kenyan mangrove forests. The total processed sediment produced by burrowing and foraging activities in a population from a peri-urban mangrove area receiving untreated domestic sewage was compared with that from a forest not affected by urban wastewater. The results showed how the peri-urban site hosted a higher biomass of crabs, which produced a significantly lower amount of processed sediment compared with the pristine site, resulting in a lower total top sediment mixing activity of the crabs. Thus, the present study showed a link between sewage exposure and top sediment reworking by crabs, which is potentially beneficial for mangrove growth and ecosystem functioning. This represents a possible example of cryptic ecological degradation in mangal systems.


Assuntos
Avicennia , Braquiúros/crescimento & desenvolvimento , Esgotos/análise , Poluentes da Água/análise , Animais , Comportamento Animal/efeitos dos fármacos , Biomassa , Braquiúros/efeitos dos fármacos , Ecossistema , Meio Ambiente , Monitoramento Ambiental , Sedimentos Geológicos/química , Rhizophoraceae , Árvores , Eliminação de Resíduos Líquidos , Poluentes da Água/toxicidade , Áreas Alagadas
7.
Environ Pollut ; 159(2): 636-45, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21050628

RESUMO

Tropical coastal ecosystems, such as mangroves, have a great ecological and socioeconomic importance for adjacent systems and local populations, but intensive environmental impact monitoring is still lacking, mainly in East Africa. This study evaluated the potential anthropogenic disturbance on Palaemon concinnus population structure and fitness. Palaemon concinnus populations from one peri-urban (domestic sewage impacted) and two pristine mangrove creeks were studied by sampling nearly 100 shrimps per location every 15 days for 12 months. The shrimps at the peri-urban location were larger, experienced longer reproductive periods, presented higher proportion of ovigerous females and better embryo quality when compared with shrimps inhabiting pristine locations. Physiological indices (RNA/DNA ratio) were similar between shrimps at pristine and peri-urban mangroves. However, a higher level of parasitation by a Bopyridae isopod, Pseudione elongata indicated some degree of stress on the host at the peri-urban mangrove, with potential effects on the host population dynamics.


Assuntos
Monitoramento Ambiental/métodos , Palaemonidae/fisiologia , Esgotos/análise , Poluição da Água , Animais , Ecossistema , Feminino , Isópodes/fisiologia , Moçambique , Palaemonidae/genética , Palaemonidae/parasitologia , Reprodução , Esgotos/parasitologia , Estresse Fisiológico
8.
Mar Pollut Bull ; 60(4): 560-72, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20004418

RESUMO

Benthic metabolism (measured as CO(2) production) and carbon oxidation pathways were evaluated in 4 mangrove mesocosms subjected daily to seawater or 60% sewage in the absence or presence of mangrove trees and biogenic structures (pneumatophores and crab burrows). Total CO(2) emission from darkened sediments devoid of biogenic structures at pristine conditions was comparable during inundation (immersion) and air exposure (emersion), although increased 2-7 times in sewage contaminated mesocosms. Biogenic structures increased low tide carbon gas emissions at contaminated (30%) and particularly pristine conditions (60%). When sewage was loaded into the mesocosms under unvegetated and planted conditions, iron reduction was substituted by sulfate reduction and contribution of aerobic respiration to total metabolism remained above 50%. Our results clearly show impacts of sewage on the partitioning of electron acceptors in mangrove sediment and confirm the importance of biogenic structures for biogeochemical functioning but also on greenhouse gases emission.


Assuntos
Avicennia/fisiologia , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Poluentes da Água/química , Áreas Alagadas , Animais , Braquiúros/fisiologia , Dióxido de Carbono/química , Metano/química
9.
Environ Pollut ; 158(1): 258-66, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19640623

RESUMO

The effect of different sewage concentrations (0, 20, 60 and 100%), vegetation (Bare, Avicennia marina or Rhizophora mucronata) and immersion periods (immersion/emersion period of 12/12 h or 3/3 days just for 100%) conditions were studied for 6 months on survival and growth rates of Terebralia palustris (Linnaeus, 1767). Gastropods' activity and ecosystem engineering preformed at bare and A. marina planted cells and 3 sewage conditions (0, 20 and 60%) were determined. Survival rates were higher than 70% in all treatments. Growth rate decreased significantly with increasing sewage concentrations (mainly at unplanted conditions) and longer immersion periods. A complete shift (from immersion to emersion periods) and a significant decrease in mobility and consequently its engineer potential, due to sewage contamination, lead to a 3-4 fold decrease in the amount of sediment disturbed. Sewage contamination, primary producers' abundance and environmental conditions may have influenced the gastropods survival, growth and its ecosystem engineering potential.


Assuntos
Gastrópodes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Áreas Alagadas , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Ecossistema
10.
Mar Pollut Bull ; 58(12): 1860-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19683314

RESUMO

The study aimed at investigating the effects of sewage loadings on the behaviour of two fiddler crabs species maintained in a system of experimental mesocosms, built in a mangrove area in Tanzania and inundated with different seawater/sewage mixtures. Our results show that sewage loads led to a modification of the overall activity budget of the crab community as a result of increased hypertrophic conditions (high COD, increased chlorophyll-a concentrations). During their activity period, crabs inside contaminated mesocosms seemed to satisfy their feeding demand faster than those of the control cells, spending a significant longer time in other activities like courtship and territorial defence. Apart from being a good biological indication of ecosystem eutrophication, such a reduced foraging activity by fiddler crabs also depresses their sediment bioturbation activity, important factor for the health of mangrove systems, suggesting practical implications regarding the efficiency of mangrove-based wetlands for treatment of domestic sewage.


Assuntos
Comportamento Animal/efeitos dos fármacos , Braquiúros/efeitos dos fármacos , Água do Mar/química , Esgotos/análise , Poluentes da Água/toxicidade , Animais , Avicennia/metabolismo , Clorofilídeos/análise , Cidades , Ecossistema , Monitoramento Ambiental , Rhizophoraceae/metabolismo , Poluentes da Água/análise
11.
Mar Pollut Bull ; 58(11): 1694-703, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19643448

RESUMO

The effect of different organic-rich sewage concentration (0%, 20% and 60% diluted in seawater) and absence or presence of mangrove trees on the survival, bioturbation activities and burrow morphology of fiddler crabs species was assessed. After 6 months, males of both species always showed higher survival ( approximately 80%) when compared to females ( approximately 20%). Crabs inhabiting pristine conditions achieved higher survival (67-87%) than those living in sewage-exposed mesocosms (40-71%). At 60% sewage loading, fiddler crabs processed less sediment (34-46%) during feeding and excavated slightly more sediment (45-80%) than at pristine conditions. While percent volume of the burrow chambers increased (13-66%) at contaminated mesocosms for both vegetation conditions, burrows were shallower (approximately 33%) in bare cells loaded with sewage. The results show that fiddler crabs presented moderate mortality levels in these artificial mangrove wetlands, but mainly in sewage impacted cells. However, they still function as ecosystem engineers through bioturbation activities and burrow construction.


Assuntos
Braquiúros/fisiologia , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Esgotos/efeitos adversos , Poluentes da Água/análise , Áreas Alagadas , Animais , Planejamento Ambiental , Feminino , Masculino , Rhizophoraceae , Eliminação de Resíduos Líquidos
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