4,678 research outputs found
Complex Network Tools to Understand the Behavior of Criminality in Urban Areas
Complex networks are nowadays employed in several applications. Modeling
urban street networks is one of them, and in particular to analyze criminal
aspects of a city. Several research groups have focused on such application,
but until now, there is a lack of a well-defined methodology for employing
complex networks in a whole crime analysis process, i.e. from data preparation
to a deep analysis of criminal communities. Furthermore, the "toolset"
available for those works is not complete enough, also lacking techniques to
maintain up-to-date, complete crime datasets and proper assessment measures. In
this sense, we propose a threefold methodology for employing complex networks
in the detection of highly criminal areas within a city. Our methodology
comprises three tasks: (i) Mapping of Urban Crimes; (ii) Criminal Community
Identification; and (iii) Crime Analysis. Moreover, it provides a proper set of
assessment measures for analyzing intrinsic criminality of communities,
especially when considering different crime types. We show our methodology by
applying it to a real crime dataset from the city of San Francisco - CA, USA.
The results confirm its effectiveness to identify and analyze high criminality
areas within a city. Hence, our contributions provide a basis for further
developments on complex networks applied to crime analysis.Comment: 7 pages, 2 figures, 14th International Conference on Information
Technology : New Generation
Ontologies and Unified Modeling Language: an approach to representation of domains of knowledge
This article emphasizes the use of Unified Modeling Language, UML in the specification of models based on ontologies in the representation of domains of knowledge, emphasizing the importance of semantic and of treatment of standardized language so the knowledge of the domain can be organized and shared. Finally, this article aims to establish a connection between the themes: the object oriented modeling and ontologies.Este artigo destaca o uso da Unified Modeling Language, UML na especificação de modelos baseados em ontologias na representação de domínios de conhecimento, enfatizando a importância da semântica e do tratamento da linguagem padronizada para que o conhecimento do domínio possa ser organizado e compartilhado. Finalmente, este artigo tem como objetivo estabelecer uma conexão entre as temáticas: modelagem orientada a objetos e ontologias
Exploring Lip Segmentation Techniques in Computer Vision: A Comparative Analysis
Lip segmentation is crucial in computer vision, especially for lip reading.
Despite extensive face segmentation research, lip segmentation has received
limited attention. The aim of this study is to compare state-of-the-art lip
segmentation models using a standardized setting and a publicly available
dataset. Five techniques, namely EHANet, Mask2Former, BiSeNet V2, PIDNet, and
STDC1, are qualitatively selected based on their reported performance,
inference time, code availability, recency, and popularity. The CelebAMask-HQ
dataset, comprising manually annotated face images, is used to fairly assess
the lip segmentation performance of the selected models. Inference experiments
are conducted on a Raspberry Pi4 to emulate limited computational resources.
The results show that Mask2Former and EHANet have the best performances in
terms of mIoU score. BiSeNet V2 demonstrate competitive performance, while
PIDNet excels in recall but has lower precision. Most models present inference
time ranging from 1000 to around 3000 milliseconds on a Raspberry Pi4, with
PIDNet having the lowest mean inference time. This study provides a
comprehensive evaluation of lip segmentation models, highlighting their
performance and inference times. The findings contribute to the development of
lightweight techniques and establish benchmarks for future advances in lip
segmentation, especially in IoT and edge computing scenarios
Identification by MALDI-TOF MS of Sporothrix brasiliensis isolated from a subconjunctival infiltrative lesion in an immunocompetent patient
Sporotrichosis is a globally distributed subcutaneous fungal infection caused by dimorphic fungi belonging to the Sporothrix species complex that affects the skin of limbs predominantly, but not exclusively. A rare case of ocular sporotrichosis in an immunocompetent Brazilian patient from the countryside of Rio de Janeiro State is reported. A 68-year-old woman presented with a subconjunctival infiltrative lesion in the right eye with pre-auricular lymphadenopathy of onset 4 months ago that evolved to suppurative nodular lesions on the eyelids. Conjunctival secretion was evaluated by histopathological examination and inoculated on Sabouraud Dextrose Agar (SDA). Histopathology showed oval bodies within giant cells and other mononucleated histiocytes. Fungus grown on SDA was identified as Sporothrix sp. by morphological observations. The isolated strain was finally identified by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) associated with an in-house database enriched with reference Sporothrix complex spectra. The strain presented a MALDI spectrum with the ion peaks of the molecular mass profile of S. brasiliensis. The patient was adequately treated with amphotericin B subsequently replaced by itraconazole. Due to scars left by the suppurative process, the patient presented poor final visual acuity. The present work presents an overview of ocular sporotrichosis and discusses the diagnostic difficulty that can lead to visual sequelae in these cases.Financial support for this work by Fundação de Amparo à Pesquisa do Rio de Janeiro [FAPERJ] (Grants:
INST E-26/010.001784/2016; JCNE E-26/203.301/2017), by Conselho Nacional de Desenvolvimento Científico
e Tecnológico [CNPq] (Grant Proc. 409227/2016-1). This study was financed in part by the Coordenação de
Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES). MALDI-TOF MS analyses were partially developed using equipment funded by CONICYT/Chile through the project Fondequip EQM160054 2016. The Universidad de La Frontera (Temuco, Chile) partially funded this work through the Project DIUFRO PIA19-0001. Furthermore, this study was also supported by FCT under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio
Reação a Meloidogyne graminicola de genótipos de soja cultivados em terras baixas.
Objetivo desse estudo, avaliar a reação de diferentes genótipos de soja cultivadas em ambiente de terras baixas a referida espécie do nematoide das galhas.CIC UFPEL
Brewers' spent grain as substrates for production of cellulolytic and hemicellulolytic enzymes by different Aspergillus species
Brewers' spent grain (BSG) is the major by-product of the brewing industry, representing around 85% of the
total by-products generated. It is a lignocellulosic material containing about 38% cellulose, 29%
hemicellulose, chiefly arabinoxylans, and 13% lignin. The production of cellulolytic and hemicellulolytic
enzymes using this material as substrate represent an eco-friendly strategy for the lignocellulosic biomass
hydrolysis, generating fermentable sugars that can be converted into high- added value products, such as
bioethanol, lactic acid, xylitol and others. Thus, this work aimed to evaluate the potential of cellulolytic and
hemicellulolytic enzymes production by some Aspergillus species cultivated in BSG. Fungi were grown in
minimum media, pH 6.5, with 1% BSG and inoculum was done with 107spores/mL, cultivated at 30°C, 120
rpm, for 5 days. Every 24 hours 2 mL of the samples were collected. The enzymatic activity was performed
after the incubation of the crude extract with 1% Linear arabinan, Xylan from beechwood, Xyloglucan, Locust
bean gum and CMC, at 50°C for 60 minutes and the reducing sugars were determined using dinitrosalicylic
acid (DNS). Synthetic substrates (2 mM of PNP--L-arabinofuranoside, PNP--D-xylopyranoside, PNP--Dglucopyranoside
and PNP--D-cellobioside) were also used at the same conditions. The extract from A.
niveus showed the best arabinanase (0.284 U/mL) and -glucosidase (0.126 U/mL) activities after 48 and 96
hours of cultivation, respectively. On the other hand, the extract from A. brasiliensis presented the best
activities of -L-arabinofuranosidase (0.129 U/mL), -xylosidase (0.265 U/mL) and xylanase (2.15 U/mL)
when cultivated for 48 hours. After 72 hours, this fungus also showed the best activities for xyloglucanase
(1.06 U/mL), mannanase (0.617 U/mL) and endoglucanase (0.254 U/mL). The extract produced by A. flavus
presented the best cellobiohydrolase activity with 0.113 U/mL after 120 hours of cultivation. It is important to
mention that A. awamori, A. clavatus and A. terreus also showed good levels of different enzymes produced
but they were not the best producers. These data suggest the great potential of different cellulolytic and
hemicellulolytic enzymes production using BSG as substrate, which represents an eco-friendly destination
for the residues and can generate high-added value products with great biotechnological application.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Institutos Nacionais de Ciência e Tecnologia (INCT)Fundação para a Ciência e a Tecnologia (FCT)info:eu-repo/semantics/publishedVersio
The brown dwarf population in the Chamaeleon I cloud
We present the results of a multiband survey for brown dwarfs in the
Chamaeleon I dark cloud with the Wide Field Imager (WFI) camera at the ESO/MPG
2.2-m telescope on La Silla (Chile). The survey has revealed a substantial
population of brown dwarfs in this southern star forming region. Candidates
were selected from R, I and H-alpha imaging observations. We also observed in
two medium-band filters, M855 and M915, for the purpose of spectral type
determination. The former filter covers a wavelength range containing spectral
features characteristic of M-dwarfs, while the latter lies in a relatively
featureless wavelength region for these late-type objects. A correlation was
found between spectral type and (M855-M915) colour index for mid- to late
M-type objects and early L-type dwarfs. With this method, we identify most of
our object candidates as being of spectral type M5 or later. Our results show
that there is no strong drop in the number of objects for the latest spectral
types, hence brown dwarfs may be as abundant as low-mass stars in this region.
Also, both kind of objects have a similar spatial distribution. We derive an
index of the mass function in this region of dispersed
star formation, in good agreement with the values obtained in other star
forming regions and young clusters. Some of the brown dwarfs have strong
H-alpha emission, suggesting mass accretion. For objects with published
infrared photometry, we find that strong H-alpha emission is related to a
mid-infrared excess, indicative of the existence of a circumstellar disk.Comment: Accepted for publication in Astronomy & Astrophysic
A large spectroscopic sample of L and T dwarfs from UKIDSS LAS : peculiar objects, binaries, and space density
This is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record [F. Marocco, et al, 'A large spectroscopic sample of L and T dwarfs from UKIDSS LAS: peculiar objects, binaries, and space density', MNRAS, Vol. 449)4): 3651-3692, April 2015] is available online at: https://doi.org/10.1093/mnras/stv530.We present the spectroscopic analysis of a large sample of late-M, L, and T dwarfs from UKIDSS. Using the YJHK photometry from ULAS and the red-optical photometry from SDSS we selected a sample of 262 brown dwarf candidates and we followed-up 196 of them using X-shooter on the VLT. The large wavelength coverage (0.30-2.48 m) and moderate resolution (R~5000-9000) of X-shooter allowed us to identify peculiar objects including 22 blue L dwarfs, 2 blue T dwarfs, and 2 low gravity M dwarfs. Using a spectral indices-based technique we identified 27 unresolved binary candidates, for which we determined the spectral type of the potential components via spectral deconvolution. The spectra allowed us to measure the equivalent width of the prominent absorption features and to compare them to atmospheric models. Cross-correlating the spectra with a radial velocity standard, we measured the radial velocity for our targets, and we determined the distribution of the sample, which is centred at -1.71.2 km s with a dispersion of 31.5 km s. Using our results we estimated the space density of field brown dwarfs and compared it with the results of numerical simulations. Depending on the binary fraction, we found that there are (0.850.55) x 10 to (1.000.64) x 10 objects per cubic parsec in the L4-L6.5 range, (0.730.47) x 10 to (0.850.55) x 10 objects per cubic parsec in the L7-T0.5 range, and (0.740.48) x 10 to (0.880.56) x 10 objects per cubic parsec in the T1-T4.5 range. There seem to be an excess of objects in the L/T transition with respect to the late T dwarfs, a discrepancy that could be explained assuming a higher binary fraction than expected for the L/T transition, or that objects in the high-mass end and low-mass end of this regime form in different environments, i.e. following different IMFs.Peer reviewe
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