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1.
Heredity (Edinb) ; 127(4): 373-383, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34400819

RESUMO

Inbreeding depression, the decline in fitness of inbred individuals, is a ubiquitous phenomenon of great relevance in evolutionary biology and in the fields of animal and plant breeding and conservation. Inbreeding depression is due to the expression of recessive deleterious alleles that are concealed in heterozygous state in noninbred individuals, the so-called inbreeding load. Genetic purging reduces inbreeding depression by removing these alleles when expressed in homozygosis due to inbreeding. It is generally thought that fast inbreeding (such as that generated by full-sib mating lines) removes only highly deleterious recessive alleles, while slow inbreeding can also remove mildly deleterious ones. However, a question remains regarding which proportion of the inbreeding load can be removed by purging under slow inbreeding in moderately large populations. We report results of two long-term slow inbreeding Drosophila experiments (125-234 generations), each using a large population and a number of derived lines with effective sizes about 1000 and 50, respectively. The inbreeding load was virtually exhausted after more than one hundred generations in large populations and between a few tens and over one hundred generations in the lines. This result is not expected from genetic drift alone, and is in agreement with the theoretical purging predictions. Computer simulations suggest that these results are consistent with a model of relatively few deleterious mutations of large homozygous effects and partially recessive gene action.


Assuntos
Depressão por Endogamia , Endogamia , Alelos , Animais , Drosophila melanogaster/genética , Melhoramento Vegetal
2.
Sensors (Basel) ; 21(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071344

RESUMO

With the exponential increase in information, it has become imperative to design mechanisms that allow users to access what matters to them as quickly as possible. The recommendation system (RS) with information technology development is the solution, it is an intelligent system. Various types of data can be collected on items of interest to users and presented as recommendations. RS also play a very important role in e-commerce. The purpose of recommending a product is to designate the most appropriate designation for a specific product. The major challenge when recommending products is insufficient information about the products and the categories to which they belong. In this paper, we transform the product data using two methods of document representation: bag-of-words (BOW) and the neural network-based document combination known as vector-based (Doc2Vec). We propose three-criteria recommendation systems (product, package and health) for each document representation method to foster online grocery shopping, which depends on product characteristics such as composition, packaging, nutrition table, allergen, and so forth. For our evaluation, we conducted a user and expert survey. Finally, we compared the performance of these three criteria for each document representation method, discovering that the neural network-based (Doc2Vec) performs better and completely alters the results.

3.
Sensors (Basel) ; 21(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572798

RESUMO

A mobile ad hoc network (MANET) is a set of autonomous mobile devices connected by wireless links in a distributed manner and without a fixed infrastructure. Real-time multimedia services, such as video-streaming over MANETs, offers very promising applications, e.g., two members of a group of tourists who want to share a video transmitted through the MANET they form, a video-streaming service deployed over a MANET where users watch a film, among other examples. On the other hand, social web technologies, where people actively interact online with others through social networks, are leading to a socialization of networks. Information of interaction among users is being used to provide socially-enhanced software. To achieve this, we need to know the strength of the relationship between a given user and each user they interact with. This strength of the relationship can be measured through a concept called tie strength (TS), first introduced by Mark Granovetter in 1973. In this article, we modify our previous proposal named multipath multimedia dynamic source routing (MMDSR) protocol to include a social metric TS in the decisions taken by the forwarding algorithm. We find a trade-off between the quality of service (QoS) and the trust level between users who form the forwarding path in the MANET. Our goal is to increase the trust metric while the QoS is not affected significantly.

4.
Sensors (Basel) ; 20(15)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32718093

RESUMO

Performance analysis is an essential task in high-performance computing (HPC) systems, and it is applied for different purposes, such as anomaly detection, optimal resource allocation, and budget planning. HPC monitoring tasks generate a huge number of key performance indicators (KPIs) to supervise the status of the jobs running in these systems. KPIs give data about CPU usage, memory usage, network (interface) traffic, or other sensors that monitor the hardware. Analyzing this data, it is possible to obtain insightful information about running jobs, such as their characteristics, performance, and failures. The main contribution in this paper was to identify which metric/s (KPIs) is/are the most appropriate to identify/classify different types of jobs according to their behavior in the HPC system. With this aim, we had applied different clustering techniques (partition and hierarchical clustering algorithms) using a real dataset from the Galician computation center (CESGA). We concluded that (i) those metrics (KPIs) related to the network (interface) traffic monitoring provided the best cohesion and separation to cluster HPC jobs, and (ii) hierarchical clustering algorithms were the most suitable for this task. Our approach was validated using a different real dataset from the same HPC center.

5.
Sensors (Basel) ; 20(14)2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32708983

RESUMO

Smart meters are of the basic elements in the so-called Smart Grid. These devices, connected to the Internet, keep bidirectional communication with other devices in the Smart Grid structure to allow remote readings and maintenance. As any other device connected to a network, smart meters become vulnerable to attacks with different purposes, like stealing data or altering readings. Nowadays, it is becoming more and more popular to buy and plug-and-play smart meters, additionally to those installed by the energy providers, to directly monitor the energy consumption at home. This option inherently entails security risks that are under the responsibility of householders. In this paper, we focus on an open solution based on Smartpi 2.0 devices with two purposes. On the one hand, we propose a network configuration and different data flows to exchange data (energy readings) in the home. These flows are designed to support collaborative among the devices in order to prevent external attacks and attempts of corrupting the data. On the other hand, we check the vulnerability by performing two kind of attacks (denial of service and stealing and changing data by using a malware). We conclude that, as expected, these devices are vulnerable to these attacks, but we provide mechanisms to detect both of them and to solve, by applying cooperation techniques.

6.
Sensors (Basel) ; 19(1)2018 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-30597987

RESUMO

Since smart cities aim at becoming self-monitoring and self-response systems, their deployment relies on close resource monitoring through large-scale urban sensing. The subsequent gathering of massive amounts of data makes essential the development of event-filtering mechanisms that enable the selection of what is relevant and trustworthy. Due to the rise of mobile event producers, location information has become a valuable filtering criterion, as it not only offers extra information on the described event, but also enhances trust in the producer. Implementing mechanisms that validate the quality of location information becomes then imperative. The lack of such strategies in cloud architectures compels the adoption of new communication schemes for Internet of Things (IoT)-based urban services. To serve the demand for location verification in urban event-based systems (DEBS), we have designed three different fog architectures that combine proximity and cloud communication. We have used network simulations with realistic urban traces to prove that the three of them can correctly identify between 73% and 100% of false location claims.

7.
Mol Ecol ; 24(17): 4419-32, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26222582

RESUMO

The adaptive potential of a population depends on the amount of additive genetic variance for quantitative traits of evolutionary importance. This variance is a direct function of the expected frequency of heterozygotes for the loci which affect the trait (QTL). It has been argued, but not demonstrated experimentally, that long-term response to selection is more dependent on QTL allelic diversity than on QTL heterozygosity. Conservation programmes, aimed at preserving this variation, usually rely on neutral markers rather than on quantitative traits for making decisions on management. Here, we address, both through simulation analyses and experimental studies with Drosophila melanogaster, the question of whether allelic diversity for neutral markers is a better indicator of a high adaptive potential than expected heterozygosity. In both experimental and simulation studies, we established synthetic populations for which either heterozygosity or allelic diversity was maximized using information from QTL (simulations) or unlinked neutral markers (simulations and experiment). The synthetic populations were selected for the quantitative trait to evaluate the evolutionary potential provided by the two optimization methods. Our results show that maximizing the number of alleles of a low number of markers implies higher responses to selection than maximizing their heterozygosity.


Assuntos
Adaptação Biológica/genética , Drosophila melanogaster/genética , Variação Genética , Heterozigoto , Locos de Características Quantitativas , Alelos , Animais , Simulação por Computador , Feminino , Masculino , Repetições de Microssatélites , Modelos Genéticos , Seleção Genética
8.
Nat Genet ; 56(5): 809-818, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38671320

RESUMO

Here, in a multi-ancestry genome-wide association study meta-analysis of kidney cancer (29,020 cases and 835,670 controls), we identified 63 susceptibility regions (50 novel) containing 108 independent risk loci. In analyses stratified by subtype, 52 regions (78 loci) were associated with clear cell renal cell carcinoma (RCC) and 6 regions (7 loci) with papillary RCC. Notably, we report a variant common in African ancestry individuals ( rs7629500 ) in the 3' untranslated region of VHL, nearly tripling clear cell RCC risk (odds ratio 2.72, 95% confidence interval 2.23-3.30). In cis-expression quantitative trait locus analyses, 48 variants from 34 regions point toward 83 candidate genes. Enrichment of hypoxia-inducible factor-binding sites underscores the importance of hypoxia-related mechanisms in kidney cancer. Our results advance understanding of the genetic architecture of kidney cancer, provide clues for functional investigation and enable generation of a validated polygenic risk score with an estimated area under the curve of 0.65 (0.74 including risk factors) among European ancestry individuals.


Assuntos
Carcinoma de Células Renais , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Renais , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Humanos , Carcinoma de Células Renais/genética , Estudos de Casos e Controles , Neoplasias Renais/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , População Branca/genética , População Negra
9.
Nanomaterials (Basel) ; 12(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35957051

RESUMO

Antibiotic resistance is a leading cause of death worldwide. In this paper, we explore new alternatives in the treatment of infections. Noble metal nanoparticles could help to mitigate this problem. In this work, palladium nanoparticles were synthesized by laser ablation in order to explore their antimicrobial capacity. To obtain palladium nanoparticles, a palladium plate immersed in water, or methanol, was ablated, using two pulsed lasers that emit radiation with wavelengths of 532 nm and 1064 nm, respectively. Pure Pd-NPs with crystalline microstructure and rounded shape were obtained. The nanoparticles' size is more homogeneous if the laser wavelength is 532 nm, and it decreases when methanol is used as solvent, reaching mean diameters smaller than 6 nm. With the objective of studying antimicrobial activity against Staphylococcus aureus, the Pd-NPs were immobilized on the surface of titanium discs. The release of palladium ions was recorded during the first seven days, and the cytotoxicity of the immobilized NPs was also tested with L929 mouse fibroblast cell line. Palladium nanoparticles synthesized by means of the infrared laser in methanol showed a strong inhibitory effect on S. aureus and good cytocompatibility, with no toxic effect on fibroblast cells.

10.
JCO Glob Oncol ; 7: 671-685, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33974442

RESUMO

PURPOSE: To assess the effect of clinical and pathological variables on cancer-specific and overall survival (OS) in de novo metastatic patients from a collaborative of primarily Latin American countries. PATIENTS AND METHODS: Of 4,060 patients with renal cell carcinoma diagnosed between 1990 and 2015, a total of 530 (14.5%) had metastasis at clinical presentation. Relationships between clinical and pathological parameters and treatment-related outcomes were analyzed by Cox regression and the log-rank method. RESULTS: Of 530 patients, 184 (90.6%) had died of renal cell carcinoma. The median OS of the entire cohort was 24 months. American Society of Anesthesiology classification 3-4 (hazard ratio [HR]: 1.64), perirenal fat invasion (HR: 2.02), and ≥ 2 metastatic organ sites (HR: 2.19) were independent prognostic factors for 5-year OS in multivariable analyses. We created a risk group stratification with these variables: no adverse risk factors (favorable group), median OS not reached; one adverse factor (intermediate group), median OS 33 months (HR: 2.04); and two or three adverse factors (poor risk group), median OS 14 months (HR: 3.58). CONCLUSION: Our study defines novel prognostic factors that are relevant to a Latin American cohort. With external validation, these easily discerned clinical variables can be used to offer prognostic information across low- and middle-income countries.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , América Latina/epidemiologia , Prognóstico , Resultado do Tratamento , Estados Unidos
11.
Evolution ; 70(8): 1856-70, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27302839

RESUMO

Inbreeding depression for fitness traits is a key issue in evolutionary biology and conservation genetics. The magnitude of inbreeding depression, though, may critically depend on the efficiency of genetic purging, the elimination or recessive deleterious mutations by natural selection after they are exposed by inbreeding. However, the detection and quantification of genetic purging for nonlethal mutations is a rather difficult task. Here, we present two comprehensive sets of experiments with Drosophila aimed at detecting genetic purging in competitive conditions and quantifying its magnitude. We obtain, for the first time in competitive conditions, an estimate for the predictive parameter, the purging coefficient (d), that quantifies the magnitude of genetic purging, either against overall inbreeding depression (d ≈ 0.3), or against the component ascribed to nonlethal alleles (dNL ≈ 0.2). We find that competitive fitness declines at a high rate when inbreeding increases in the absence of purging. However, in moderate size populations under competitive conditions, inbreeding depression need not be too dramatic in the medium to short term, as the efficiency of purging is also very high. Furthermore, we find that purging occurred under competitive conditions also reduced the inbreeding depression that is expressed in the absence of competition.


Assuntos
Evolução Biológica , Drosophila melanogaster/genética , Aptidão Genética , Seleção Genética , Animais , Meio Ambiente , Endogamia , Densidade Demográfica
12.
PLoS One ; 10(3): e0114302, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25760732

RESUMO

Collaboration among scholars and institutions is progressively becoming essential to the success of research grant procurement and to allow the emergence and evolution of scientific disciplines. Our work focuses on analysing if the volume of collaborations of one author together with the relevance of his collaborators is somewhat related to his research performance over time. In order to prove this relation we collected the temporal distributions of scholars' publications and citations from the Google Scholar platform and the co-authorship network (of Computer Scientists) underlying the well-known DBLP bibliographic database. By the application of time series clustering, social network analysis and non-parametric statistics, we observe that scholars with similar publications (citations) patterns also tend to have a similar centrality in the co-authorship network. To our knowledge, this is the first work that considers success evolution with respect to co-authorship.


Assuntos
Autoria , Comportamento Cooperativo , Publicações , Ciência , Bibliometria , Bases de Dados Bibliográficas , Humanos , Publicações/estatística & dados numéricos
13.
Rev. méd. Urug ; 31(3): 165-171, set. 2015. tab
Artigo em Espanhol | LILACS | ID: lil-763424

RESUMO

Introducción: el cáncer de mama (CM) es el cáncer más frecuente en la mujer uruguaya, cada año se registran unos 1.840 casos nuevos y unas 660 mujeres mueren como consecuencia de esta enfermedad. Con el fin de mejorar la calidad de la asistencia de las pacientes portadoras de patología mamaria se creó la Unidad Docente Asistencial de Mastología (UDAM) en el año 2009. Objetivo: valorar la calidad de la asistencia en la UDAM del Hospital de Clínicas. Material y método: estudio observacional, retrospectivo, que incluyó a las pacientes diagnosticadas y tratadas por CM en una UDAM desde junio de 2009 hasta junio de 2014. Para valorar la calidad de la asistencia se utilizaron los indicadores propuestos por la Sociedad Europea de Mastología (EUSOMA) en 2010. Resultados: se incluyeron 115 pacientes tratadas por CM; la mediana de edad fue de 63 años, la mayoría de las pacientes tuvieron CM limitados a la mama o axila, receptores hormonales (RRHH) positivos / HER2 negativos. Se cumplieron los criterios de calidad relacionados con el diagnóstico preoperatorio, informe anatomopatológico, tratamiento quirúrgico, radiante y oncológico. Sin embargo, en el 40% de los casos el intervalo de tiempo entre el diagnóstico y el primer tratamiento oncológico fue superior a seis semanas. Conclusiones: la atención recibida por las pacientes asistidas en nuestra UDAM en el período de referencia cumplió con la mayoría de los indicadores propuestos por EUSOMA. Se destaca la necesidad de mejorar el tiempo de espera entre el diagnóstico y el primer tratamiento oncológico.


Introduction: breast cancer is the most frequent types of cancer in Uruguayan women. Every year there are 1,840 new cases and around 660 women die from this disease. The Mastology Teaching Unit was created in 2009 to improve the quality of assistance in patients with breast cancer. Objective: to evaluate the quality of assistance at the Mastology Teaching Unit of the University Hospital. Method: observational, retrospective study that included women diagnosed and treated for breast cancer in a Mastology Teaching Unit from June 2009 through June, 2014. In order to evaluate the quality of assistance the indicators suggested by the European Society of Mastology in 2010 were used. Results: 115 patients treated for breast cancer were included in the study. Average age was 63 years old, most patients had breast cancer limited in the breast or armpit, (RRHH) positive hormonal receptors, HER2 negative. The quality criteria associated to preoperative diagnosis, pathology analysis, surgical treatment, radiotherapy and oncologic treatment were met. However, in 40% of cases the time interval between diagnosis and the first oncologic treatment was over six weeks. Conclusions: care received by patients seen at the Mastology Unit during the referred period met most indicators suggested by the European Society of Mastology. The need to improve the waiting time between diagnosis and the first oncologic treatment is emphasized.


Introdução: no Uruguai o câncer de mama (CM) é o tipo mais frequente na mulher; a cada ano aproximadamente 1.840 casos novos são registrados e 660 mulheres morrem como consequência desta patologia. Buscando melhorar a qualidade da assistência prestada às pacientes portadoras desta patologia mamaria, em 2009, foi criada a Unidade Docente Assistencial de Mastologia (UDAM). Objetivo: avaliar a qualidade da assistência na UDAM do Hospital de Clínicas. Material e método: estudo observacional, retrospectivo, incluindo as pacientes diagnosticadas e tratadas por CM na UDAM no período junho de 2009 - junho de 2014. Para avaliar a qualidade da assistência foram utilizados os indicadores propostos em 2010 pela Sociedade Europeia de Mastologia (EUSOMA). Resultados: foram incluídas 115 pacientes tratadas por CM; a mediana de idade foi 63 anos; a maioria das pacientes apresentaram CM limitados a mama ou axila, receptores hormonais (RRHH) positivos / HER2 negativos. Os critérios de qualidade relacionados com diagnóstico pré-operatório, laudo anatomopatológico, tratamento cirúrgico, radiante e oncológico foram observados. No entanto, em 40% dos casos o intervalo de tempo entre o diagnóstico e o primeiro tratamento oncológico foi superior a seis semanas. Conclusões: a atenção recebida pelas pacientes assistidas na UDAM no período de estudo cumpriu com a maioria dos indicadores propostos pela EUSOMA. Destaca-se a necessidade de melhorar o tempo de espera entre o diagnóstico e o primeiro tratamento oncológico.


Assuntos
Humanos , Qualidade da Assistência à Saúde , Hospitais de Ensino , Neoplasias da Mama
14.
In. Misa Jalda, Ricardo. Atlas de patología anal: clínica y terapéutica. [Montevideo], s.n, [2016]. p.297-313, ilus.
Monografia em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1379078
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