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3.
Sensors (Basel) ; 21(15)2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34372408

RESUMEN

False-ceiling inspection is a critical factor in pest-control management within a built infrastructure. Conventionally, the false-ceiling inspection is done manually, which is time-consuming and unsafe. A lightweight robot is considered a good solution for automated false-ceiling inspection. However, due to the constraints imposed by less load carrying capacity and brittleness of false ceilings, the inspection robots cannot rely upon heavy batteries, sensors, and computation payloads for enhancing task performance. Hence, the strategy for inspection has to ensure efficiency and best performance. This work presents an optimal functional footprint approach for the robot to maximize the efficiency of an inspection task. With a conventional footprint approach in path planning, complete coverage inspection may become inefficient. In this work, the camera installation parameters are considered as the footprint defining parameters for the false ceiling inspection. An evolutionary algorithm-based multi-objective optimization framework is utilized to derive the optimal robot footprint by minimizing the area missed and path-length taken for the inspection task. The effectiveness of the proposed approach is analyzed using numerical simulations. The results are validated on an in-house developed false-ceiling inspection robot-Raptor-by experiment trials on a false-ceiling test-bed.


Asunto(s)
Robótica , Algoritmos
4.
Sensors (Basel) ; 21(16)2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34450767

RESUMEN

Routine rodent inspection is essential to curbing rat-borne diseases and infrastructure damages within the built environment. Rodents find false ceilings to be a perfect spot to seek shelter and construct their habitats. However, a manual false ceiling inspection for rodents is laborious and risky. This work presents an AI-enabled IoRT framework for rodent activity monitoring inside a false ceiling using an in-house developed robot called "Falcon". The IoRT serves as a bridge between the users and the robots, through which seamless information sharing takes place. The shared images by the robots are inspected through a Faster RCNN ResNet 101 object detection algorithm, which is used to automatically detect the signs of rodent inside a false ceiling. The efficiency of the rodent activity detection algorithm was tested in a real-world false ceiling environment, and detection accuracy was evaluated with the standard performance metrics. The experimental results indicate that the algorithm detects rodent signs and 3D-printed rodents with a good confidence level.


Asunto(s)
Redes Neurales de la Computación , Roedores , Algoritmos , Animales , Ratas
5.
Sensors (Basel) ; 21(16)2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34450805

RESUMEN

Area coverage is a crucial factor for a robot intended for applications such as floor cleaning, disinfection, and inspection. Robots with fixed shapes could not realize an adequate level of area coverage performance. Reconfigurable robots have been introduced to overcome the limitations of fixed-shape robots, such as accessing narrow spaces and cover obstacles. Although state-of-the-art reconfigurable robots used for coverage applications are capable of shape-changing for improving the area coverage, the reconfiguration is limited to a few predefined shapes. It has been proven that the ability of reconfiguration beyond a few shapes can significantly improve the area coverage performance of a reconfigurable robot. In this regard, this paper proposes a novel robot model and a low-level controller that can facilitate the reconfiguration beyond a small set of predefined shapes and locomotion per instructions while firmly maintaining the shape. A prototype of a robot that facilitates the aim mentioned above has been designed and developed. The proposed robot model and controller have been integrated into the prototype, and experiments have been conducted considering various reconfiguration and locomotion scenarios. Experimental results confirm the validity of the proposed model and controller during reconfiguration and locomotion of the robot. Moreover, the applicability of the proposed model and controller for achieving high-level autonomous capabilities has been proven.


Asunto(s)
Robótica , Locomoción
6.
J Tissue Eng Regen Med ; 5(2): 112-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20653040

RESUMEN

To establish an ex vivo expansion method of haematopoietic progenitor cells (HPCs) and erythroid cells, three-dimensional (3D) cultures of mouse bone marrow cells were performed, employing a porous polyvinyl formal (PVF) resin as a scaffold. In these cultures, the effects of oxygen concentration and co-cultures with stromal cells on the expansion of HPCs and erythroid cells were investigated. When bone marrow cells were cultured under 3D conditions, HPCs and erythroid cells expanded without supplementation of exogenous cytokines, irrespective of the presence of stromal cells. On the contrary, slight expansion of HPCs or erythroid cells was observed in monolayer cultures as controls, indicating that the 3D cultures using the PVF scaffold were far better in expanding HPCs and erythroid cells than the monolayer cultures. Under hypoxic conditions, bone marrow stromal cells allowed for a 3D culture of erythroid cells and HPCs at higher cell densities compared to cultures without stromal cells, and the duration of the expansion of HPCs and erythroid cells after initiating the 3D co-cultures was prolonged. The number of these cells increased throughout the culture period up to 3 weeks under hypoxic conditions, although the number decreased after 2 weeks under normoxic conditions. In conclusion, the 3D co-culture method of haematopoietic cells with stromal cells under hypoxic conditions was confirmed to be effective in expanding HPCs and erythroid cells, and this method seemed to be useful for developing an ex vivo expansion method for haematopoietic cells.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Células Madre Hematopoyéticas/citología , Oxígeno/farmacología , Polivinilos , Andamios del Tejido , Animales , Técnicas de Cultivo de Célula , Hipoxia de la Célula , Técnicas de Cocultivo , Células Madre Hematopoyéticas/metabolismo , Ratones , Oxígeno/metabolismo , Porosidad , Células del Estroma/citología , Células del Estroma/metabolismo
7.
Acta Trop ; 111(3): 275-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19464245

RESUMEN

All artemisinin-based combination therapies (ACTs), recommended by the World Health Organization, are 3-day regimens. A considerable level of non-compliance on ACTs has been reported from some countries. The study aimed to assess the therapeutic efficacy of single dose treatment with new generation ACT containing artemisinin plus naphthoquine. An oral single dose of eight tablets (400 mg of naphthoquine+1000 mg artemisinin) of the combination drug was administered to adult uncomplicated falciparum malaria patients. Observations of fever, parasite clearance and reappearance, and other clinical manifestations were made on Days 0, 1, 2, 3, 7, 14, 21 and 28. Fifty-three adult falciparum positive cases, with fever or history of fever within the previous 24 h, were included in the final evaluation of the study. Mean fever clearance time, parasite clearance time were 18.2+/-8.6 h and 34.6+/-14.3 h, respectively. Adequate clinical and parasitological response was achieved in 52 cases, the rate being 98.1% (95% CI, 91.1-99.9). One patient was classified as late parasitological failure because of the reappearance of falciparum parasite on Day 14. The drug was well tolerated and no adverse reactions were detected in the patients. Since it is a single dose therapy, health workers can administer the drug as directly observed treatment.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Naftoquinonas/uso terapéutico , Administración Oral , Adolescente , Adulto , Animales , Antimaláricos/administración & dosificación , Antimaláricos/efectos adversos , Artemisininas/administración & dosificación , Artemisininas/efectos adversos , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Naftoquinonas/administración & dosificación , Naftoquinonas/efectos adversos , Parasitemia , Plasmodium falciparum/aislamiento & purificación , Resultado del Tratamiento , Adulto Joven
8.
J Biomed Mater Res ; 61(1): 75-82, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12001249

RESUMEN

Porous polyvinyl formal (PVF) resin and poly(lactide-caprolactone) [P(LA/CL)] sponges were examined as three-dimensional matrices for chondroinduction of cultured bone marrow mesenchymal stem cells (MSCs). Approximately 5 x 10(5) mouse MSCs were seeded in porous PVF resin or P(LA/CL) sponges and were cultured for up to 1 month in serum-free high-glucose Dulbecco's modified Eagle's medium containing 10 ng/mL transforming growth factor-beta3 and 100 nM dexamethasone for chondroinduction. After the 1-month culture period, the PVF resin and P(LA/CL) sponges contained approximately twice the amount of glycosaminoglycans compared with the control pellet. Safranin-O staining of PVF and P(LA/CL) after 1 month of culture revealed a cartilage-like extracellular matrix containing glycosaminoglycans and collagen. When implanted into nude mice, PVF and P(LA/CL) seeded with MSCs were found to be both biocompatible and chondroinductive. These highly porous scaffolds can maintain a large number of cells in a three-dimensional structure. Both are potentially promising for the chondroinduction of bone marrow MSCs for research and clinical applications.


Asunto(s)
Condrogénesis/fisiología , Técnicas de Cultivo/métodos , Mesodermo/citología , Poliésteres/química , Células Madre/fisiología , Animales , Materiales Biocompatibles/química , Trasplante de Células , Medio de Cultivo Libre de Suero , Glicosaminoglicanos/metabolismo , Masculino , Mesodermo/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Células Madre/citología , Células Madre/metabolismo
9.
Artif Organs ; 26(4): 333-9, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11952504

RESUMEN

To develop a culture system for bone marrow (BM) cell expansion, we examined the effect of growth factors (GFs) on the proliferation and differentiation of BM cells cultured in three-dimensional (3D) scaffolds of porous polyvinyl formal (PVF) resin. Murine BM cells were cultured for 2 weeks in the PVF resin or in culture dishes as a control, in the presence or absence of 4 GFs (erythropoietin, stem cell factor, interleukin [IL]-3, and IL-6). These GFs remarkably stimulated cell proliferation both in PVF and dish cultures. In addition, the PVF cultures showed enhanced cell proliferation in comparison with the corresponding dish cultures. Moreover, PVF cultures with GFs revealed the highest number of colony-forming units and the highest percentage of hematopoietic progenitor cells (HPCs) among all the cultures examined. Therefore, this 3D PVF culture system with GFs is considered as a potential alternative method for the ex vivo expansion of HPCs.


Asunto(s)
Células de la Médula Ósea , Técnicas de Cultivo de Célula/métodos , Sustancias de Crecimiento/farmacología , Animales , División Celular , Medios de Cultivo , Células Precursoras Eritroides , Ratones , Ratones Endogámicos C57BL , Polivinilos
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