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111.
Nicola Pellicciotta Ojus Satish Bagal Viridiana Carmona Sosa Giacomo Frangipane Gaszton Vizsnyiczai Roberto Di Leonardo 《Advanced functional materials》2023,33(39):2214801
Biohybrid microbots integrate biological actuators and sensors into synthetic chassis with the aim of providing the building blocks of next-generation micro-robotics. One of the main challenges is the development of self-assembled systems with consistent behavior and such that they can be controlled independently to perform complex tasks. Herein, it is shown that, using light-driven bacteria as propellers, 3D printed microbots can be steered by unbalancing light intensity over different microbot parts. An optimal feedback loop is designed in which a central computer projects onto each microbot a tailor-made light pattern, calculated from its position and orientation. In this way, multiple microbots can be independently guided through a series of spatially distributed checkpoints. By exploiting a natural light-driven proton pump, these bio-hybrid microbots are able to extract mechanical energy from light with such high efficiency that, in principle, hundreds of these systems can be controlled simultaneously with a total optical power of just a few milliwatts. 相似文献
112.
Leonardo Reboucas de Carvalho Alba Cristina Alves Melo Aleteia Araujo 《Concurrency and Computation》2023,35(18):e7595
The Hirschberg algorithm is commonly used for protein sequence alignment, which is a very important task in bioinformatics. This article presents the AFMC framework for using the Hirschberg method to perform sequence alignment in multiple cloud computing services of different models, such as Infrastructure-as-a-Service and Function-as-a-Service (FaaS). Experiments were carried out in which several instances of AWS EC2, Azure VMs and Google Compute Engine as well as varied configurations of AWS Lambda, Azure Function, and Google Cloud Function were used to pairwise align COVID-19 spike proteins. The services were submitted to different levels of simultaneity to align the genetic sequences. The findings reveal that there is a tradeoff between predicted execution time and cost for this application, for example, FaaS-oriented cloud service models generally took less time to process the workloads. On the other hand, it was observed that, as the level of concurrence increased, there was a marked augmentation in cost. In this context, a framework that provides multi cloud solutions for bioinformatics such as AFMC is essential. 相似文献
113.
Leonardo Fagundes-Junior Michael Canesche Ricardo Ferreira Alexandre Brandão 《Concurrency and Computation》2023,35(24):e7767
Recently, high-performance computing strategies have been implemented to improve performance analysis and reduce the development time of new solutions in robotic applications, such as path planning, machine learning, and vision, which require massive matrix computations. In this sense, this work aims to study the aerial robots' behavior during their mission execution. Due to the large search space in the set of parameter combinations and the high computational cost required to perform such an analysis after sequentially executing thousands of simulations, this work proposes an open-source graphics processing unit (GPU)-based implementation to simulate the robot behavior. A GPU-accelerated flight route analysis for multi-unmanned aerial vehicle (UAV) systems is proposed for the tuning control problem in the parameters‘ space considering the problem of delay in sending information to a ground control station. Considering our implementation, the experimental results show a speedup up to 325, 629, and 5959 in comparison to the parallel version with 16 threads, C coder converter, and native Matlab code, respectively. The implementation is available in the Colab Google platform and it can easily be expanded for analyses involving larger amounts of different parameters, robot models, strategies, and controllers. 相似文献
114.
Dias Menezes Leonardo de Araújo Luciano Vieira Nishijima Marislei 《International Journal of Information Security》2023,22(4):869-880
International Journal of Information Security - This paper proposes a blockchain solution for some activities currently performed by notary offices under the Civil Law judiciary that is technically... 相似文献
115.
Adriana Dillenburg Meinhart Tayse Ferreira Ferreira da Silveira Mateus Henrique Petrarca Leonardo Henrique Silva Maria Rosa de Moraes Cristiano Augusto Ballus Patrícia Oliveira de Souza Thais Cristina Lima de Souza Roger Wagner Helena Maria André Bolini Roy Edward Bruns Helena Teixeira Godoy 《European Journal of Lipid Science and Technology》2017,119(10)
116.
117.
Maria Paola Di Santo Leonardo Vignoli Giuseppe M. Carpaneto Corrado Battisti 《Lakes & Reservoirs: Research and Management》2017,22(1):56-64
The patterns of the occurrence and distribution of alien freshwater turtle species in an urban pond archipelago (Rome, Italy) were analysed, with the aim of exploring the role of a set of factors (type of ponds, landscape context, size area, distance from the nearest road) with a generalized linear model approach. A total of 311 ponds subdivided in three types (fountains, small basins, lakes) embedded in different landscape contexts (public parks, private parks, urban areas) at differing distances from the nearest road were sampled. Six non‐native freshwater turtle species in 31 sites were recorded (9.97%). Lakes exhibited the highest occurrence rates of alien freshwater turtles, compared to small basins and fountains. Freshwater turtle species in urbanized areas were only observed in parks (both public and private). In both the public and private parks, the lakes exhibited the highest percentage of occupied sites, with fountains being the lowest. A direct and significant relationship was observed between pond size and species richness. The distance from the nearest road did not appear to affect species richness. A first interpretation of the data from this study facilitated the postulation of two a posteriori hypotheses that should be tested, as follows: (i) the causal process of turtle release is random, and the rate of extinction (and recapture) is higher in smaller ponds, thus producing the observed pattern; and (ii) the turtle release is not random, and people actively select the ponds they consider more suitable for their pet animals. In this study, it appears the lakes were perceived by those who abandon their pets as the most ecologically suitable habitats among other pond types to accommodate the different species of turtles. Knowledge of people's attitudes in regard to releasing pet animals also might assist managers of public green spaces to develop strategies aimed to preserve local biodiversity, and to educate the public about the conservation issue represented by the alien species. 相似文献
118.
James C. K. Dillon Leonardo Bezerra María del Pilar Sosa Peña Nicole M. Neu‐Baker Sara A. Brenner 《Microscopy research and technique》2017,80(5):462-470
Hyperspectral imaging (HSI) and mapping are increasingly used for visualization and identification of nanoparticles (NPs) in a variety of matrices, including aqueous suspensions and biological samples. Reference spectral libraries (RSLs) contain hyperspectral data collected from materials of known composition and are used to detect the known materials in experimental samples through a one‐to‐one pixel “mapping” process. In some HSI studies, RSLs created from raw NPs were used to map NPs in experimental samples in a different matrix; for example, RSLs created from NPs in suspension to map NPs in biological tissue. Others have utilized RSLs created from NPs in the same matrix. However, few studies have systematically compared hyperspectral data as a function of the matrix in which the NPs are found and its impact on mapping results. The objective of this study is to compare RSLs created from metal oxide NPs in aqueous suspensions to RSLs created from the same NPs in rat tissues following in vivo inhalation exposure, and to investigate the differences in mapping that result from the use of each RSL. Results demonstrate that the spectral profiles of these NPs are matrix dependent: RSLs created from NPs in positive control tissues mapped to experimental tissues more appropriately than RSLs created from NPs in suspension. Aqueous suspension RSLs mapped 0‐602 out of 500,424 pixels per tissue image while tissue RSLs mapped 689‐18,435 pixels for the same images. This study underscores the need for appropriate positive controls for the creation of RSLs for mapping NPs in experimental samples. 相似文献
119.
120.
Ronaldo C. Gurgel‐Loureno Leonardo M. Pinto Luis A. V. Bezerra Jorge I. Snchez‐Botero 《河流研究与利用》2020,36(7):1353-1359
Several fish species from Central America and other regions have been introduced into Brazil. In this study, we evaluated the bioecological aspects of a non‐native cichlid of the genus Amatitlania (convict cichlid) and its possible establishment in high‐altitude forest enclaves of semi‐arid Northeastern Brazil. Specimens of Amatitlania nigrofasciata (Günther, 1867) were captured in a local stream displaying abiotic conditions like those of its natural range of distribution. The individuals collected were predominantly adult, insectivorous and displayed normal length–weight relationships, although we observed some phenotypical plasticity (variation in body depth, and a morphologically abnormal dorsal fin in three cases). Our results indicate that A. nigrofasciata has successfully colonized an Atlantic forest enclave in the Brazilian semi‐arid region, making it necessary to adopt measures to prevent the species from spreading to other water bodies in the surroundings. 相似文献