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1.
Syst Biol ; 73(2): 455-469, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-38284268

RESUMEN

Phylogenies are central to many research areas in biology and commonly estimated using likelihood-based methods. Unfortunately, any likelihood-based method, including Bayesian inference, can be restrictively slow for large datasets-with many taxa and/or many sites in the sequence alignment-or complex substitutions models. The primary limiting factor when using large datasets and/or complex models in probabilistic phylogenetic analyses is the likelihood calculation, which dominates the total computation time. To address this bottleneck, we incorporated the high-performance phylogenetic library BEAGLE into RevBayes, which enables multi-threading on multi-core CPUs and GPUs, as well as hardware specific vectorized instructions for faster likelihood calculations. Our new implementation of RevBayes+BEAGLE retains the flexibility and dynamic nature that users expect from vanilla RevBayes. In addition, we implemented native parallelization within RevBayes without an external library using the message passing interface (MPI); RevBayes+MPI. We evaluated our new implementation of RevBayes+BEAGLE using multi-threading on CPUs and 2 different powerful GPUs (NVidia Titan V and NVIDIA A100) against our native implementation of RevBayes+MPI. We found good improvements in speedup when multiple cores were used, with up to 20-fold speedup when using multiple CPU cores and over 90-fold speedup when using multiple GPU cores. The improvement depended on the data type used, DNA or amino acids, and the size of the alignment, but less on the size of the tree. We additionally investigated the cost of rescaling partial likelihoods to avoid numerical underflow and showed that unnecessarily frequent and inefficient rescaling can increase runtimes up to 4-fold. Finally, we presented and compared a new approach to store partial likelihoods on branches instead of nodes that can speed up computations up to 1.7 times but comes at twice the memory requirements.


Asunto(s)
Teorema de Bayes , Filogenia , Programas Informáticos , Clasificación/métodos , Biología Computacional/métodos
2.
Syst Biol ; 68(6): 1052-1061, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31034053

RESUMEN

BEAGLE is a high-performance likelihood-calculation library for phylogenetic inference. The BEAGLE library defines a simple, but flexible, application programming interface (API), and includes a collection of efficient implementations for calculation under a variety of evolutionary models on different hardware devices. The library has been integrated into recent versions of popular phylogenetics software packages including BEAST and MrBayes and has been widely used across a diverse range of evolutionary studies. Here, we present BEAGLE 3 with new parallel implementations, increased performance for challenging data sets, improved scalability, and better usability. We have added new OpenCL and central processing unit-threaded implementations to the library, allowing the effective utilization of a wider range of modern hardware. Further, we have extended the API and library to support concurrent computation of independent partial likelihood arrays, for increased performance of nucleotide-model analyses with greater flexibility of data partitioning. For better scalability and usability, we have improved how phylogenetic software packages use BEAGLE in multi-GPU (graphics processing unit) and cluster environments, and introduced an automated method to select the fastest device given the data set, evolutionary model, and hardware. For application developers who wish to integrate the library, we also have developed an online tutorial. To evaluate the effect of the improvements, we ran a variety of benchmarks on state-of-the-art hardware. For a partitioned exemplar analysis, we observe run-time performance improvements as high as 5.9-fold over our previous GPU implementation. BEAGLE 3 is free, open-source software licensed under the Lesser GPL and available at https://beagle-dev.github.io.


Asunto(s)
Clasificación/métodos , Programas Informáticos/normas , Interpretación Estadística de Datos , Filogenia
3.
Front Zool ; 15: 43, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30473719

RESUMEN

BACKGROUND: A number of shelled and shell-less gastropods are known to use multiple defensive mechanisms, including internally generated or externally obtained biochemically active compounds and structures. Within Nudipleura, nudibranchs within Cladobranchia possess such a special defense: the ability to sequester cnidarian nematocysts - small capsules that can inject venom into the tissues of other organisms. This ability is distributed across roughly 600 species within Cladobranchia, and many questions still remain in regard to the comparative morphology and evolution of the cnidosac - the structure that houses sequestered nematocysts (called kleptocnides). In this paper, we describe cnidosac morphology across the main groups of Cladobranchia in which it occurs, and place variation in its structure in a phylogenetic context to better understand the evolution of nematocyst sequestration. RESULTS: Overall, we find that the length, size and structure of the entrance to the cnidosac varies more than expected based on previous work, as does the structure of the exit, the musculature surrounding the cnidosac, and the position and orientation of the kleptocnides. The sequestration of nematocysts has originated at least twice within Cladobranchia based on the phylogeny presented here using 94 taxa and 409 genes. CONCLUSIONS: The cnidosac is not homologous to cnidosac-like structures found in Hancockiidae. Additionally, the presence of a sac at the distal end of the digestive gland may have originated prior to the sequestration of nematocysts. This study provides a more complete picture of variation in, and evolution of, morphological characters associated with nematocyst sequestration in Cladobranchia.

4.
Syst Biol ; 61(1): 170-3, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21963610

RESUMEN

Phylogenetic inference is fundamental to our understanding of most aspects of the origin and evolution of life, and in recent years, there has been a concentration of interest in statistical approaches such as Bayesian inference and maximum likelihood estimation. Yet, for large data sets and realistic or interesting models of evolution, these approaches remain computationally demanding. High-throughput sequencing can yield data for thousands of taxa, but scaling to such problems using serial computing often necessitates the use of nonstatistical or approximate approaches. The recent emergence of graphics processing units (GPUs) provides an opportunity to leverage their excellent floating-point computational performance to accelerate statistical phylogenetic inference. A specialized library for phylogenetic calculation would allow existing software packages to make more effective use of available computer hardware, including GPUs. Adoption of a common library would also make it easier for other emerging computing architectures, such as field programmable gate arrays, to be used in the future. We present BEAGLE, an application programming interface (API) and library for high-performance statistical phylogenetic inference. The API provides a uniform interface for performing phylogenetic likelihood calculations on a variety of compute hardware platforms. The library includes a set of efficient implementations and can currently exploit hardware including GPUs using NVIDIA CUDA, central processing units (CPUs) with Streaming SIMD Extensions and related processor supplementary instruction sets, and multicore CPUs via OpenMP. To demonstrate the advantages of a common API, we have incorporated the library into several popular phylogenetic software packages. The BEAGLE library is free open source software licensed under the Lesser GPL and available from http://beagle-lib.googlecode.com. An example client program is available as public domain software.


Asunto(s)
Biología Computacional/métodos , Filogenia , Programas Informáticos , Algoritmos , Metodologías Computacionales , Evolución Molecular , Genoma
5.
Syst Biol ; 61(3): 539-42, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22357727

RESUMEN

Since its introduction in 2001, MrBayes has grown in popularity as a software package for Bayesian phylogenetic inference using Markov chain Monte Carlo (MCMC) methods. With this note, we announce the release of version 3.2, a major upgrade to the latest official release presented in 2003. The new version provides convergence diagnostics and allows multiple analyses to be run in parallel with convergence progress monitored on the fly. The introduction of new proposals and automatic optimization of tuning parameters has improved convergence for many problems. The new version also sports significantly faster likelihood calculations through streaming single-instruction-multiple-data extensions (SSE) and support of the BEAGLE library, allowing likelihood calculations to be delegated to graphics processing units (GPUs) on compatible hardware. Speedup factors range from around 2 with SSE code to more than 50 with BEAGLE for codon problems. Checkpointing across all models allows long runs to be completed even when an analysis is prematurely terminated. New models include relaxed clocks, dating, model averaging across time-reversible substitution models, and support for hard, negative, and partial (backbone) tree constraints. Inference of species trees from gene trees is supported by full incorporation of the Bayesian estimation of species trees (BEST) algorithms. Marginal model likelihoods for Bayes factor tests can be estimated accurately across the entire model space using the stepping stone method. The new version provides more output options than previously, including samples of ancestral states, site rates, site d(N)/d(S) rations, branch rates, and node dates. A wide range of statistics on tree parameters can also be output for visualization in FigTree and compatible software.


Asunto(s)
Clasificación/métodos , Programas Informáticos , Algoritmos , Cadenas de Markov , Modelos Biológicos , Método de Montecarlo , Filogenia
6.
Harmful Algae ; 119: 102334, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36344195

RESUMEN

In the Pacific Northwest, blooms of the diatom Pseudo-nitzschia (PN) sometimes produce domoic acid, a neurotoxin that causes amnesic shellfish poisoning, leading to a Harmful Algal Bloom (HAB) event. The Pacific Northwest (PNW) HAB Bulletin project, a partnership between academic, government, and tribal stakeholders, uses a combination of beach and offshore monitoring data and ocean forecast modeling to better understand the formation, evolution, and transport of HABs in this region. This project produces periodic Bulletins to inform local stakeholders of current and forecasted conditions. The goal of this study was to help improve how the forecast model is used in the Bulletin's preparation through a retrospective particle-tracking experiment. Using past observations of beach PN cell counts, events were identified that likely originated in the Juan de Fuca eddy, a known PN hotspot, and then particle tracks were used in the model to simulate these events. A variety of "beaching definitions" were tested, based on both water depth and distance offshore, to define when a particle in the model was close enough to the coast that it was likely to correspond to cells appearing in the intertidal zone and in shellfish diets, as well as a variety of observed PN cell thresholds to determine what cell count should be used to describe an event that would warrant further action. The skill of these criteria was assessed by determining the fraction of true positives, true negatives, false positives, and false negatives within the model in comparison with observations, as well as a variety of derived model performance metrics. This analysis suggested that for our stakeholders' purposes, the most useful beaching definition is the 30 m isobath and the most useful PN cell threshold for coincident field-based sample PN density estimates is 10,000 PN cells/L. Lastly, the performance of a medium-resolution (1.5 km horizontal resolution) version of the model was compared with that of a high-resolution (0.5 km horizontal resolution) version, the latter currently used in forecasting for the PNW HAB Bulletin project. This analysis includes a direct comparison of the two model resolutions for one overlapping year (2017). These results suggested that a narrower, more realistic beaching definition is most useful in a high-resolution model, while a wider beaching definition is more appropriate in a lower resolution model like the medium-resolution version used in this analysis. Overall, this analysis demonstrated the importance of incorporating stakeholder needs into the statistical approach in order to generate the most effective decision-support information from oceanographic modeling.


Asunto(s)
Diatomeas , Intoxicación por Mariscos , Floraciones de Algas Nocivas , Estudios Retrospectivos , Predicción
7.
Methods Mol Biol ; 1910: 691-722, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31278682

RESUMEN

In this chapter, we focus on the computational challenges associated with statistical phylogenomics and how use of the broad-platform evolutionary analysis general likelihood evaluator (BEAGLE), a high-performance library for likelihood computation, can help to substantially reduce computation time in phylogenomic and phylodynamic analyses. We discuss computational improvements brought about by the BEAGLE library on a variety of state-of-the-art multicore hardware, and for a range of commonly used evolutionary models. For data sets of varying dimensions, we specifically focus on comparing performance in the Bayesian evolutionary analysis by sampling trees (BEAST) software between multicore central processing units (CPUs) and a wide range of graphics processing cards (GPUs). We put special emphasis on computational benchmarks from the field of phylodynamics, which combines the challenges of phylogenomics with those of modelling trait data associated with the observed sequence data. In conclusion, we show that for increasingly large molecular sequence data sets, GPUs can offer tremendous computational advancements through the use of the BEAGLE library, which is available for software packages for both Bayesian inference and maximum-likelihood frameworks.


Asunto(s)
Teorema de Bayes , Biología Computacional , Genómica , Filogenia , Programas Informáticos , Animales , Biología Computacional/métodos , Evolución Molecular , Genómica/métodos , Humanos , Cadenas de Markov , Modelos Estadísticos , Método de Montecarlo , Reproducibilidad de los Resultados
8.
Virus Evol ; 4(1): vey016, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29942656

RESUMEN

The Bayesian Evolutionary Analysis by Sampling Trees (BEAST) software package has become a primary tool for Bayesian phylogenetic and phylodynamic inference from genetic sequence data. BEAST unifies molecular phylogenetic reconstruction with complex discrete and continuous trait evolution, divergence-time dating, and coalescent demographic models in an efficient statistical inference engine using Markov chain Monte Carlo integration. A convenient, cross-platform, graphical user interface allows the flexible construction of complex evolutionary analyses.

9.
Environ Int ; 101: 70-79, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28109640

RESUMEN

Domoic acid (DA) is a neurotoxin that is naturally produced by phytoplankton and accumulates in seafood during harmful algal blooms. As the prevalence of DA increases in the marine environment, there is a critical need to identify seafood consumers at risk of DA poisoning. DA exposure was estimated in recreational razor clam (Siliqua patula) harvesters to determine if exposures above current regulatory guidelines occur and/or if harvesters are chronically exposed to low levels of DA. Human consumption rates of razor clams were determined by distributing 1523 surveys to recreational razor clam harvesters in spring 2015 and winter 2016, in Washington, USA. These consumption rate data were combined with DA measurements in razor clams, collected by a state monitoring program, to estimate human DA exposure. Approximately 7% of total acute exposures calculated (including the same individuals at different times) exceeded the current regulatory reference dose (0.075mgDA·kgbodyweight-1·d-1) due to higher than previously reported consumption rates, lower bodyweights, and/or by consumption of clams at the upper range of legal DA levels (maximum 20mg·kg-1 wet weight for whole tissue). Three percent of survey respondents were potentially at risk of chronic DA exposure by consuming a minimum of 15 clams per month for at 12 consecutive months. These insights into DA consumption will provide an additional tool for razor clam fishery management.


Asunto(s)
Bivalvos/química , Contaminación de Alimentos/análisis , Ácido Kaínico/análogos & derivados , Toxinas Marinas/análisis , Neurotoxinas/análisis , Adolescente , Adulto , Animales , Niño , Exposición Dietética , Femenino , Humanos , Ácido Kaínico/análisis , Ácido Kaínico/envenenamiento , Masculino , Toxinas Marinas/envenenamiento , Persona de Mediana Edad , Neurotoxinas/envenenamiento , Nivel sin Efectos Adversos Observados , Recreación , Encuestas y Cuestionarios , Washingtón
10.
J Med Case Rep ; 7: 126, 2013 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-23668825

RESUMEN

INTRODUCTION: Paracoccidioidomycosis is a systemic mycosis in Latin America that can affect various organs. Few case reports of paracoccidioidomycosis affecting the prostate are found in the literature. CASE PRESENTATION: We present the case of a 79-year-old Caucasian man with a six-month history of irritative symptoms of the prostate (urgency, frequency and nocturia) and difficulty initiating urination that progressed to urinary retention and the use of a urinary catheter. The anatomopathological analysis of the transurethral resection of the prostate revealed chronic granulomatous prostatitis of fungal etiology (paracoccidioidomycosis) with extensive necrosis. The patient began treatment with itraconazole at a dose of 100mg/day for six months. Radiography of the thorax revealed bilaterally diffuse nodular reticular interstitial lesions. The patient progressed to respiratory failure and was sent to the intensive care unit, but suffered a cardiopulmonary arrest and was pronounced dead. CONCLUSIONS: Due to the high incidence of paracoccidioidomycosis in countries like Brazil, urologists should suspect blastomycosis in all patients with symptoms of lower urinary obstruction with chronic abacterial prostatitis. Considering that paracoccidioidomycosis has the potential to affect various organs, following diagnosis, the treatment must be initiated as soon as possible.

11.
Einstein (Sao Paulo) ; 9(4): 545-9, 2011 Dec.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-26761263

RESUMEN

Premature ejaculation is the most frequent male sexual dysfunction, estimated to affect 20 to 30% of men at some time in their life. A Pubmed search from the year 2000 to the present was performed to retrieve publications related to management or treatment of premature ejaculation. Behavioral techniques have been the mainstay of premature ejaculation management for many years, although evidence of their short-term efficacy is limited. Topical therapies for premature ejaculation act by desensitizing the penis and do not alter the sensation of ejaculation. Selective serotonin reuptake inhibitors (SSRIs), commonly used in the treatment of depression, are often used to treat premature ejaculation, based on the observation that delayed ejaculation is a frequent side effect of this drug class. Dapoxetine is a short-acting SSRI formulated to treat premature ejaculation, and results seem very promising.

12.
Einstein (Säo Paulo) ; 9(4)out.-dec. 2011.
Artículo en Inglés, Portugués | LILACS | ID: lil-612043

RESUMEN

Premature ejaculation is the most frequent male sexual dysfunction, estimated to affect 20 to 30% of men at some time in their life. A Pubmed search from the year 2000 to the present was performed to retrieve publications related to management or treatment of premature ejaculation. Behavioral techniques have been the mainstay of premature ejaculation management for many years, although evidence of their short-term efficacy is limited. Topical therapies for premature ejaculation act by desensitizing the penis and do not alter the sensation of ejaculation. Selective serotonin reuptake inhibitors (SSRIs), commonly used in the treatment of depression, are often used to treat premature ejaculation, based on the observation that delayed ejaculation is a frequent side effect of this drug class. Dapoxetine is a short-acting SSRI formulated to treat premature ejaculation, and results seem very promising.


A ejaculação precoce é a disfunção sexual masculina mais frequente, com uma estimativa de acometimento de 20 a 30% dos homens em algum momento da vida. Foi realizada uma busca no Pubmed, do ano 2000 até os dias atuais, com a finalidade de revisar publicações relacionadas ao manejo e ao tratamento da ejaculação precoce. Terapias comportamentais foram a base do manejo da ejaculação precoce por muitos anos, embora as evidências de sua eficácia a curto prazo sejam limitadas. Terapias de uso tópico agem por meio de dessensibilização do pênis, mas não alteram a sensação da ejaculação. Os inibidores seletivos da recaptação da serotonina são utilizados para depressão e, em geral, também para tratar ejaculação precoce, com base na observação de que o retardo na ejaculação é um efeito colateral frequente dessa classe de drogas. A dapoxetina é um inibidor seletivo da recaptação da serotonina de curta ação, que foi formulado para tratar a ejaculação precoce, e seus resultados parecem muito promissores.


Asunto(s)
Humanos , Masculino , Coito , Eyaculación , Disfunción Eréctil , Inhibidores Selectivos de la Recaptación de Serotonina , Educación Sexual , Conducta Sexual
14.
Belém-Pa; POLIGRAFIA; 2008. 103 p.
Monografía en Portugués | ColecionaSUS | ID: biblio-934272
15.
Belém; Sociedade Civil Mamirauá; 2007. 364 p. Acompanha CD-ROM.
Monografía en Portugués | ColecionaSUS | ID: biblio-932551
16.
Belém; Sociedade Civil Mamirauá; 2005. 324 p. Acompanha CD-ROM.
Monografía en Portugués | ColecionaSUS | ID: biblio-932552
17.
Belém; Sociedade Civil Mamirauá; 2003. 290 p. Acompanha CD-ROM.
Monografía en Portugués | ColecionaSUS | ID: biblio-932550

Asunto(s)
Biometría
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