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1.
Mol Cell ; 68(6): 1120-1133.e3, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29249654

RESUMO

The ability to respond to available nutrients is critical for all living cells. The AMP-activated protein kinase (SNF1 in yeast) is a central regulator of metabolism that is activated when energy is depleted. We found that SNF1 activity in the nucleus is regulated by controlled relocalization of the SNF1 activator Std1 into puncta. This process is regulated by glucose through the activity of the previously uncharacterized protein kinase Vhs1 and its substrate Sip5, a protein of hitherto unknown function. Phosphorylation of Sip5 prevents its association with Std1 and triggers Std1 accretion. Reversible Std1 puncta formation occurs under non-stressful, ambient conditions, creating non-amyloid inclusion bodies at the nuclear-vacuolar junction, and it utilizes cellular chaperones similarly to the aggregation of toxic or misfolded proteins such as those associated with Parkinson's, Alzheimer's, and CJD diseases. Our results reveal a controlled, non-pathological, physiological role of protein aggregation in the regulation of a major metabolic cellular pathway.


Assuntos
Glucose/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Agregados Proteicos , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Redes e Vias Metabólicas , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Edulcorantes/farmacologia
2.
Arch Phys Med Rehabil ; 103(7): 1477-1486, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35421395

RESUMO

The application of Rasch Measurement (RM) Theory to rehabilitation assessments has proliferated in recent years. RM Theory helps design and refine assessments so that items reflect a unidimensional construct in an equal interval metric that distinguishes among persons of different abilities in a manner that is consistent with the underlying trait. Rapid growth of RM in rehabilitation assessment studies has led to inconsistent results reporting. Clear, consistent, transparent reporting of RM Theory results is important for advancing rehabilitation science and practice based on precise measures. Precise measures, in turn, provide researchers, practitioners, patients, and other stakeholders with tools for effective decision making. The goal of this Rasch Reporting Guideline for Rehabilitation Research (RULER: Rasch Reporting Guideline for Rehabilitation Research) is to provide peer-reviewed, evidence-based, transparent, and consistent recommendations for reporting studies that apply RM Theory in a rehabilitation context. The purpose of the guideline is to ensure that authors, reviewers, and editors have uniform expectations about how to write and evaluate research on rehabilitation outcome assessments. A task force of rehabilitation researchers, clinicians, and editors met regularly between November 2018 and August 2020 to identify the need for the guideline, develop an organizing framework, identify content areas, and develop the recommendations. This RULER: Rasch Reporting Guideline for Rehabilitation Research statement includes the organizing framework and a checklist of 59 recommendations. The guideline is supported by an Explanation and Elaboration article that provides more detail about the framework and recommendations in the checklist. A glossary of key terms and a recommended iterations table are provided in supplemental online only materials.


Assuntos
Revisão da Pesquisa por Pares , Pesquisa de Reabilitação , Comitês Consultivos , Lista de Checagem , Humanos , Projetos de Pesquisa , Relatório de Pesquisa
3.
Arch Phys Med Rehabil ; 103(7): 1487-1498, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35436496

RESUMO

The Rasch Reporting Guideline for Rehabilitation Research (RULER) provides peer-reviewed, evidence-based, transparent, and consistent recommendations for reporting studies that apply Rasch Measurement (RM) Theory in a rehabilitation context. The purpose of the guideline is to ensure that authors, reviewers, and editors have uniform guidance about how to write and evaluate research on rehabilitation outcome assessments. The RULER statement includes an organizing framework and a checklist of 59 recommendations. This companion article supports the RULER statement by providing details about the framework, rationale for the domains and recommendations in the checklist and explaining why these considerations are important for improving consistency and transparency in reporting the results of RM studies. This article is not intended to describe how to conduct RM studies but provides rationale for the essential elements that authors should address in each domain. Consistency and transparency in reporting RM studies will advance rehabilitation research if authors consider these issues when planning their study and include the checklist when they submit their manuscript for peer review. A copy of the checklist can be found at [table 2 in https://doi.org/10.1016/j.apmr.2022.03.013].


Assuntos
Revisão da Pesquisa por Pares , Pesquisa de Reabilitação , Lista de Checagem , Humanos , Avaliação de Resultados em Cuidados de Saúde
4.
J Fish Biol ; 101(1): 323-327, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35607969

RESUMO

A female scalloped hammerhead shark (Sphyrna lewini) conducted a species record deep dive to 1240 m in coastal-pelagic waters off Hawaii Island. This extends the deepest known depth range of the species by over 200 m (650 ft) and highlights the question of the extent to which deep-diving activity is mediated by physiological constraints, such as temperature and oxygen availability.


Assuntos
Tubarões , Animais , Feminino , Tubarões/fisiologia
5.
Philos Trans A Math Phys Eng Sci ; 379(2205): 20200317, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34275365

RESUMO

In this paper, we formulate the space-dependent variable-order fractional master equation to model clustering of particles, organelles, inside living cells. We find its solution in the long-time limit describing non-uniform distribution due to a space-dependent fractional exponent. In the continuous space limit, the solution of this fractional master equation is found to be exactly the same as the space-dependent variable-order fractional diffusion equation. In addition, we show that the clustering of lysosomes, an essential organelle for healthy functioning of mammalian cells, exhibit space-dependent fractional exponents. Furthermore, we demonstrate that the non-uniform distribution of lysosomes in living cells is accurately described by the asymptotic solution of the space-dependent variable-order fractional master equation. Finally, Monte Carlo simulations of the fractional master equation validate our analytical solution. This article is part of the theme issue 'Transport phenomena in complex systems (part 1)'.


Assuntos
Lisossomos , Animais , Análise por Conglomerados , Difusão
6.
J Cell Sci ; 131(16)2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30154086

RESUMO

Dynamic Cell III, a meeting jointly organized by the British Society of Cell Biology (BSCB) and the Biochemical Society, took place at the Manchester Conference Centre, Manchester, UK in March 2018. It brought together a diverse group of scientists from around the world, all with a shared interest in understanding how dynamic functions of the cell are fulfilled. A particular focus was the regulation of the cytoskeleton: in cell division, cell migration and cell-cell interactions. Moreover, a key theme that ran through all presented work was the development of new and exciting technologies to study dynamic cell behaviour.


Assuntos
Biologia Celular/tendências , Fenômenos Fisiológicos Celulares , Congressos como Assunto , Biologia Celular/organização & administração , Comunicação Celular , Divisão Celular/fisiologia , Movimento Celular , Biologia Computacional/tendências , Citoesqueleto/metabolismo , Matriz Extracelular/fisiologia , Humanos , Invenções , Imagem Molecular/métodos , Imagem Molecular/tendências , Proteômica/tendências , Análise de Célula Única/métodos , Análise de Célula Única/tendências
7.
Aust Occup Ther J ; 67(4): 309-319, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32168392

RESUMO

BACKGROUND AND AIMS: A number of theories have been proposed on clinical expertise and its development in occupational therapy and allied health professions. Clinical reasoning, outcome measurement and evidence-based practice are names for leading conceptualisations. The aim of this research was to develop an operational measure of habits of mind and practice that constitute these desirable professional activities amongst professional therapists. METHODS: Items were developed on the basis of literature review and feedback from an expert panel. An online self-report survey was completed by 107 occupational therapists and other allied health clinicians. Rasch analysis was used to identify and calibrate items that fit the criteria for equal-interval measurement. Residuals from identified equal-interval dimensions were examined using principal components analysis to identify multidimensionality. RESULTS: A two-dimension solution employing 32 items was identified. The first dimension comprised items on Critical Clinical Reasoning and had an item separation of 8.49 (0.99 reliability) and a person separation of 2.93 (0.90 reliability). The second dimension comprised items on Evidence-Informed Practice behaviours and had an item separation of 6.19 (0.97 reliability) and a person separation of 2.97 (0.90 reliability). These dimensions were positively correlated (r = .778, p < .001). We named the overall scale 'Evidence-Informed Professional Thinking', or EIPT. The EIPT measures correlated significantly with 12 of 13 relevant external criterion items. CONCLUSION: Evidence-informed professional thinking can be measured in terms of two correlated probabilistically equal-interval dimensions: Critical Clinical Reasoning and Evidence-Informed Practice behaviours. The EIPT measure should be useful in research on development and application of clinical expertise, quality and outcomes of care and implementation of improved practices among practicing therapists in clinical treatment settings. Further research is recommended to understand the generalisability, strengths, limitations and correlates of EIPT.


Assuntos
Pessoal Técnico de Saúde/psicologia , Tomada de Decisão Clínica/métodos , Terapeutas Ocupacionais/normas , Terapia Ocupacional/métodos , Atitude do Pessoal de Saúde , Prática Clínica Baseada em Evidências/normas , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Autoeficácia , Inquéritos e Questionários
8.
Am J Bot ; 105(9): 1568-1576, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30216409

RESUMO

PREMISE OF THE STUDY: Plant phenological responses to climate change now constitute one of the best studied areas of the ecological impacts of climate change. Flowering time responses to climate change of wind-pollinated species have, however, been less well studied. A novel source of flowering time data for wind-pollinated species is allergen monitoring records. METHODS: We studied the male flowering time response to climatic variables of two wind-pollinated genera, Betula (Betulaceae) and Populus (Salicaceae), using pollen count records over a 17-year period. KEY RESULTS: We found that changes in the pollen release envelope differed between the two genera. Over the study period, the only month with a significant rise in temperature was April, resulting in the duration of pollen release of the April-flowering Populus to shorten and the start and peak of the May-flowering Betula to advance. The quantity of pollen released by Betula has increased and was related to increases in the previous year's August precipitation, while the quantity of pollen released by Populus has not changed and was related to the previous year's summer and autumn temperatures. CONCLUSIONS: Our findings suggest that taxa differ in the reproductive consequences of environmental change. Differing shifts in phenology among species may be related to different rates of change in climatic variables in different months of the year. While our study only considers two genera, the results underscore the importance of understanding non-uniform intra-annual variation in climate when studying the ecological implications of climate change.


Assuntos
Mudança Climática , Pólen/fisiologia , Betula/fisiologia , Flores/fisiologia , Polinização , Populus/fisiologia , Vento
9.
Ecol Lett ; 20(3): 375-384, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28116770

RESUMO

Latitudinal gradients in biotic interactions have been suggested as causes of global patterns of biodiversity and phenotypic variation. Plant biologists have long speculated that outcrossing mating systems are more common at low than high latitudes owing to a greater predictability of plant-pollinator interactions in the tropics; however, these ideas have not previously been tested. Here, we present the first global biogeographic analysis of plant mating systems based on 624 published studies from 492 taxa. We found a weak decline in outcrossing rate towards higher latitudes and among some biomes, but no biogeographic patterns in the frequency of self-incompatibility. Incorporating life history and growth form into biogeographic analyses reduced or eliminated the importance of latitude and biome in predicting outcrossing or self-incompatibility. Our results suggest that biogeographic patterns in mating system are more likely a reflection of the frequency of life forms across latitudes rather than the strength of plant-pollinator interactions.


Assuntos
Cycadopsida/fisiologia , Magnoliopsida/fisiologia , Polinização , Autofertilização , Biodiversidade , Dispersão Vegetal , Reprodução
10.
Mol Cell ; 35(5): 626-41, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19682934

RESUMO

To identify regulators involved in determining the differential pattern of H3K79 methylation by Dot1, we screened the entire yeast gene deletion collection by GPS for genes required for normal levels of H3K79 di- but not trimethylation. We identified the cell cycle-regulated SBF protein complex required for H3K79 dimethylation. We also found that H3K79 di- and trimethylation are mutually exclusive, with M/G1 cell cycle-regulated genes significantly enriched for H3K79 dimethylation. Since H3K79 trimethylation requires prior monoubiquitination of H2B, we performed genome-wide profiling of H2BK123 monoubiquitination and showed that H2BK123 monoubiquitination is not detected on cell cycle-regulated genes and sites containing H3K79me2, but is found on H3K79me3-containing regions. A screen for genes responsible for the establishment/removal of H3K79 dimethylation resulted in identification of NRM1 and WHI3, both of which impact the transcription by the SBF and MBF protein complexes, further linking the regulation of methylation status of H3K79 to the cell cycle.


Assuntos
Ciclo Celular , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ciclo Celular/genética , DNA Intergênico , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Lisina , Metilação , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Transdução de Sinais , Fatores de Tempo , Fatores de Transcrição/genética , Transcrição Gênica , Enzimas de Conjugação de Ubiquitina/genética , Ubiquitinação
11.
Nature ; 464(7285): 54-8, 2010 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-20164837

RESUMO

Local adaptations within species are often governed by several interacting genes scattered throughout the genome. Single-locus models of selection cannot explain the maintenance of such complex variation because recombination separates co-adapted alleles. Here we report a previously unrecognized type of intraspecific multi-locus genetic variation that has been maintained over a vast period. The galactose (GAL) utilization gene network of Saccharomyces kudriavzevii, a relative of brewer's yeast, exists in two distinct states: a functional gene network in Portuguese strains and, in Japanese strains, a non-functional gene network of allelic pseudogenes. Genome sequencing of all available S. kudriavzevii strains revealed that none of the functional GAL genes were acquired from other species. Rather, these polymorphisms have been maintained for nearly the entire history of the species, despite more recent gene flow genome-wide. Experimental evidence suggests that inactivation of the GAL3 and GAL80 regulatory genes facilitated the origin and long-term maintenance of the two gene network states. This striking example of a balanced unlinked gene network polymorphism introduces a remarkable type of intraspecific variation that may be widespread.


Assuntos
Evolução Molecular , Redes Reguladoras de Genes/genética , Genes Fúngicos/genética , Polimorfismo Genético/genética , Saccharomyces/genética , Alelos , Galactose/metabolismo , Genoma Fúngico , Japão , Dados de Sequência Molecular , Filogenia , Portugal , Pseudogenes/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Saccharomyces/classificação , Saccharomyces/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
12.
Proc Natl Acad Sci U S A ; 110(43): 17432-7, 2013 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-24108357

RESUMO

The AMP-activated protein kinase (AMPK) is a major stress sensor of mammalian cells. AMPK's homolog in the yeast Saccharomyces cerevisiae, the SNF1 protein kinase, is a central regulator of carbon metabolism that inhibits the Snf3/Rgt2-Rgt1 glucose sensing pathway and activates genes involved in respiration. We present evidence that glucose induces modification of the Snf1 catalytic subunt of SNF1 with the small ubiquitin-like modifier protein SUMO, catalyzed by the SUMO (E3) ligase Mms21. Our results suggest that SUMOylation of Snf1 inhibits its function in two ways: by interaction of SUMO attached to lysine 549 with a SUMO-interacting sequence motif located near the active site of Snf1, and by targeting Snf1 for destruction via the Slx5-Slx8 (SUMO-directed) ubiquitin ligase. These findings reveal another way SNF1 function is regulated in response to carbon source.


Assuntos
Proteínas Serina-Treonina Quinases/metabolismo , Proteína SUMO-1/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Glucose/farmacologia , Immunoblotting , Mutação , Fosforilação/efeitos dos fármacos , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Estabilidade Proteica , Proteína SUMO-1/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sumoilação
13.
Evol Comput ; 24(1): 143-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25700148

RESUMO

In the computer vision and pattern recognition fields, image classification represents an important yet difficult task. It is a challenge to build effective computer models to replicate the remarkable ability of the human visual system, which relies on only one or a few instances to learn a completely new class or an object of a class. Recently we proposed two genetic programming (GP) methods, one-shot GP and compound-GP, that aim to evolve a program for the task of binary classification in images. The two methods are designed to use only one or a few instances per class to evolve the model. In this study, we investigate these two methods in terms of performance, robustness, and complexity of the evolved programs. We use ten data sets that vary in difficulty to evaluate these two methods. We also compare them with two other GP and six non-GP methods. The results show that one-shot GP and compound-GP outperform or achieve results comparable to competitor methods. Moreover, the features extracted by these two methods improve the performance of other classifiers with handcrafted features and those extracted by a recently developed GP-based method in most cases.


Assuntos
Reconhecimento Automatizado de Padrão/métodos , Inteligência Artificial , Simulação por Computador , Humanos , Modelos Estatísticos , Reconhecimento Automatizado de Padrão/classificação , Software , Máquina de Vetores de Suporte
14.
Genome Res ; 22(4): 681-92, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22287102

RESUMO

Although retroviruses are relatively promiscuous in choice of integration sites, retrotransposons can display marked integration specificity. In yeast and slime mold, some retrotransposons are associated with tRNA genes (tDNAs). In the Saccharomyces cerevisiae genome, the long terminal repeat retrotransposon Ty3 is found at RNA polymerase III (Pol III) transcription start sites of tDNAs. Ty1, 2, and 4 elements also cluster in the upstream regions of these genes. To determine the extent to which other Pol III-transcribed genes serve as genomic targets for Ty3, a set of 10,000 Ty3 genomic retrotranspositions were mapped using high-throughput DNA sequencing. Integrations occurred at all known tDNAs, two tDNA relics (iYGR033c and ZOD1), and six non-tDNA, Pol III-transcribed types of genes (RDN5, SNR6, SNR52, RPR1, RNA170, and SCR1). Previous work in vitro demonstrated that the Pol III transcription factor (TF) IIIB is important for Ty3 targeting. However, seven loci that bind the TFIIIB loader, TFIIIC, were not targeted, underscoring the unexplained absence of TFIIIB at those sites. Ty3 integrations also occurred in two open reading frames not previously associated with Pol III transcription, suggesting the existence of a small number of additional sites in the yeast genome that interact with Pol III transcription complexes.


Assuntos
DNA Polimerase III/genética , Mutagênese Insercional , Retroelementos/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sequência de Bases , Sítios de Ligação/genética , DNA Polimerase III/metabolismo , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Genoma Fúngico/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos , Recombinação Genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Homologia de Sequência do Ácido Nucleico , Fator de Transcrição TFIIIB/genética , Fator de Transcrição TFIIIB/metabolismo , Sítio de Iniciação de Transcrição , Transcrição Gênica
16.
Genome Res ; 21(5): 748-55, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21471402

RESUMO

Transcription factors direct gene expression, so there is much interest in mapping their genome-wide binding locations. Current methods do not allow for the multiplexed analysis of TF binding, and this limits their throughput. We describe a novel method for determining the genomic target genes of multiple transcription factors simultaneously. DNA-binding proteins are endowed with the ability to direct transposon insertions into the genome near to where they bind. The transposon becomes a "Calling Card" marking the visit of the DNA-binding protein to that location. A unique sequence "barcode" in the transposon matches it to the DNA-binding protein that directed its insertion. The sequences of the DNA flanking the transposon (which reveal where in the genome the transposon landed) and the barcode within the transposon (which identifies the TF that put it there) are determined by massively parallel DNA sequencing. To demonstrate the method's feasibility, we determined the genomic targets of eight transcription factors in a single experiment. The Calling Card method promises to significantly reduce the cost and labor needed to determine the genomic targets of many transcription factors in different environmental conditions and genetic backgrounds.


Assuntos
Mapeamento Cromossômico/métodos , Elementos de DNA Transponíveis/genética , Proteínas de Ligação a DNA/genética , Genoma Fúngico/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Fatores de Transcrição/metabolismo , Sítios de Ligação , Elementos de DNA Transponíveis/fisiologia , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Mutagênese Insercional , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/química , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética
17.
Ecology ; 95(4): 910-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24933810

RESUMO

Reproductive success in flowering plants is influenced by the morphology and timing of reproductive structures as well as the density of surrounding conspecifics. In species with separate male and female flower phases, successful pollen transfer is also expected to vary with the density and ratio of surrounding male and female flowers. Increased density of surrounding flowers may increase pollinator visitation rates, but the densities of male and female flowers will determine the availability of pollen and the strength of competition for pollen receipt. Here we (1) quantify the influence of surrounding plant density on total seasonal fruit and seed production, (2) quantify the influence of sexual neighborhood (surrounding sex ratio and densities of male- and female-phase flowers) on fruit and seed production for individual flowers presented within the season, and (3) compare the influence of plant density on fitness to that of focal plant phenotype, specifically stigma-nectary distance and plant height, in a natural population of the pollen-limited, hummingbird-pollinated hermaphrodite Lobelia cardinalis. These relationships were examined at four spatial scales (10, 20, 50, and 100 cm). By examining temporal and spatial scales we found that (1) total seed production per plant decreased with increasing plant density at the smallest scale but increased with increasing density at all larger scales; (2) at any given time, a female-phase flower benefited from a higher density of surrounding male-phase flowers and a lower density of surrounding female-phase flowers; (3) when sex ratio was explicitly analyzed, a female-phase flower benefited from a lower proportion of surrounding female flowers as well as a lower total flower density; and (4) at the whole-plant level, taller plants were more likely to produce fruit (even when accounting for total number of flowers produced), consistent with pollinator preference for taller floral displays. Our results suggest that the local density of male and female flowers (and surrounding sex ratio) influences successful pollen transfer, implying that the local floral environment may shape how attraction traits like plant height are related to fitness.


Assuntos
Lobelia/fisiologia , Polinização/fisiologia , Animais , Aves , Demografia , Flores/fisiologia , Frutas , Lobelia/genética , Polinização/genética , Sementes
18.
Proc Natl Acad Sci U S A ; 108(35): 14539-44, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21873232

RESUMO

Domestication of plants and animals promoted humanity's transition from nomadic to sedentary lifestyles, demographic expansion, and the emergence of civilizations. In contrast to the well-documented successes of crop and livestock breeding, processes of microbe domestication remain obscure, despite the importance of microbes to the production of food, beverages, and biofuels. Lager-beer, first brewed in the 15th century, employs an allotetraploid hybrid yeast, Saccharomyces pastorianus (syn. Saccharomyces carlsbergensis), a domesticated species created by the fusion of a Saccharomyces cerevisiae ale-yeast with an unknown cryotolerant Saccharomyces species. We report the isolation of that species and designate it Saccharomyces eubayanus sp. nov. because of its resemblance to Saccharomyces bayanus (a complex hybrid of S. eubayanus, Saccharomyces uvarum, and S. cerevisiae found only in the brewing environment). Individuals from populations of S. eubayanus and its sister species, S. uvarum, exist in apparent sympatry in Nothofagus (Southern beech) forests in Patagonia, but are isolated genetically through intrinsic postzygotic barriers, and ecologically through host-preference. The draft genome sequence of S. eubayanus is 99.5% identical to the non-S. cerevisiae portion of the S. pastorianus genome sequence and suggests specific changes in sugar and sulfite metabolism that were crucial for domestication in the lager-brewing environment. This study shows that combining microbial ecology with comparative genomics facilitates the discovery and preservation of wild genetic stocks of domesticated microbes to trace their history, identify genetic changes, and suggest paths to further industrial improvement.


Assuntos
Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Classificação , Ecologia , Dados de Sequência Molecular , Saccharomyces cerevisiae/classificação
19.
Evol Comput ; 22(1): 105-38, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23614773

RESUMO

Due-date assignment plays an important role in scheduling systems and strongly influences the delivery performance of job shops. Because of the stochastic and dynamic nature of job shops, the development of general due-date assignment models (DDAMs) is complicated. In this study, two genetic programming (GP) methods are proposed to evolve DDAMs for job shop environments. The experimental results show that the evolved DDAMs can make more accurate estimates than other existing dynamic DDAMs with promising reusability. In addition, the evolved operation-based DDAMs show better performance than the evolved DDAMs employing aggregate information of jobs and machines.


Assuntos
Algoritmos , Metodologias Computacionais , Modelos Teóricos , Admissão e Escalonamento de Pessoal , Linguagens de Programação
20.
Prog Orthod ; 25(1): 32, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39218838

RESUMO

BACKGROUND: Mandibular second premolar agenesis is a common problem in orthodontics and is often treated in conjunction with maxillary counterbalancing extractions. However, in cases without maxillary crowding or dental protrusion, space closure may pose challenges leading to compromised occlusal results or patient profile. Multiple techniques have been described to treat these patients; nevertheless, there is a paucity of data comparing effectiveness of space closure utilizing various anchorage techniques. The goal of this study is to assess the effectiveness of the Herbst device during mandibular molar protraction and compare it to the use of temporary anchorage device (TADs) in patients with mandibular second premolar agenesis. MATERIALS AND METHODS: This retrospective study included 33 patients with mandibular premolar agenesis treated without maxillary extractions. Of these patients, 21 were treated with protraction Herbst devices and 12 with TADs. Changes in molar and incisor positions, skeletal base positions and occlusal plane angulations were assessed on pretreatment (T0) and post-treatment (T1) lateral cephalograms. Scans/photographs at T0 and T1 were used to evaluate canine relationship changes representing anchorage control. Space closure and breakage/failure rates were also compared. Data was analyzed with paired and unpaired t-tests at the significance level of 0.05. RESULTS: Within the Herbst group, changes in mandibular central incisor uprighting and mandibular molar crown angulations were statistically significant. However, no significant differences were noted between the Herbst and TAD groups. Protraction rates as well as overall treatment times were comparable (0.77 mm/month vs. 0.55 mm/month and 3.02 years vs. 2.67 years, respectively). Canine relationships were maintained or improved toward a class I in 82.85% of the Herbst sample, compared to in 66.7% of the TAD sample. Emergency visits occurred in 80.1% of the Herbst group, with cementation failures or appliance breakages as the most common reasons. CONCLUSION: The Herbst device could be a viable modality in cases with missing mandibular premolars where maximum anterior anchorage is desired, or if patients/parents are resistant to TADs. Furthermore, they could be beneficial in skeletal class II patients with mandibular deficiency who also need molar protraction. However, the increased incidence of emergency visits must be considered when treatment is planned.


Assuntos
Dente Pré-Molar , Mandíbula , Dente Molar , Procedimentos de Ancoragem Ortodôntica , Aparelhos Ortodônticos Funcionais , Humanos , Estudos Retrospectivos , Procedimentos de Ancoragem Ortodôntica/instrumentação , Procedimentos de Ancoragem Ortodôntica/métodos , Feminino , Masculino , Estudos de Casos e Controles , Fechamento de Espaço Ortodôntico/instrumentação , Fechamento de Espaço Ortodôntico/métodos , Criança , Cefalometria , Adolescente , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Resultado do Tratamento , Desenho de Aparelho Ortodôntico , Anodontia/terapia
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