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1.
J Clin Pathol ; 77(4): 219-224, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-37258250

RESUMO

AIMS: To investigate trends in representation of women among authors and editorial boards of surgical pathology journals over the last two decades.Secondary aims: to identify barriers and potential solutions. METHODS: The names and gender of first, middle, last authors and editorial board members were obtained from original articles from seven pathology journals from various geopolitical regions in 2002, 2011 and 2021. The proportion of women first, middle, last authors and editorial board members were compared over time. RESULTS: 1097 publications and 8012 individual authors were extracted. In 2002, 2011 and 2021, respectively, the percentage of women first authors were 28.3% (257 of 907), 31.9% (566 of 1773) and 41.1% (1421 of 3457); women middle authorship rates were 30.0% (159 of 530), 32.8% (375 of 1145) and 40.9% (1067 of 2609) and women last authors were 18.0% (34 of 188), 26.0% (82 of 315) and 36.0% (152 of 422). Women representation on editorial boards has increased (11.3%, 15.8%, 26.5%), but of the chief editors, there was only one woman in 2021, while all were men in 2002 and 2011. CONCLUSIONS: To our knowledge, this study is the first to document under-representation of women among authors and editorial boards of surgical pathology journals. While women representation has increased over time, predominance of men remains relative to workforce proportions. Our findings are comparable to those from other medical fields and prompt the need to investigate the underlying causes for this imbalance and implement strategies to promote diversity, equity and inclusion in academic surgical pathology.


Assuntos
Patologia Cirúrgica , Masculino , Humanos , Feminino , Autoria
2.
Pathology ; 55(6): 760-771, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37573162

RESUMO

While women pathologists have made up over one-third of pathologists in the Australian workforce for over 15 years and at least 50% since 2019, they are under-represented in senior leadership roles, scientific publications, grant recipients, editorial boards, key presentations, and professional awards. This is not unique to pathology and is seen in the broader medical and academic community. Barriers to gender equity and equality in pathology, medicine and academia include gender stereotypes, gender-based discrimination, structural and organisational barriers as well as broader social and cultural barriers. A diverse leadership reflective of the whole professional body and the broader community is important for optimal health outcomes. It is the responsibility and moral duty of individuals and organisations to address any gender disparities, inequities, and inequalities by monitoring, identifying, and acting on gender biases and systemic barriers that hinder appropriate levels of representation by women.


Assuntos
Equidade de Gênero , Sexismo , Feminino , Humanos , Austrália , Recursos Humanos
3.
Pathology ; 55(5): 596-609, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37330338

RESUMO

Fusions involving the Neurotrophic tropomyosin receptor kinase (NTRK) gene family (NTRK1, NTRK2 and NTRK3) are targetable oncogenic alterations that are found in a diverse range of tumours. There is an increasing demand to identify tumours which harbour these fusions to enable treatment with selective tyrosine kinase inhibitors such as larotrectinib and entrectinib. NTRK fusions occur in a wide range of tumours including rare tumours such as infantile fibrosarcoma and secretory carcinomas of the salivary gland and breast, as well as at low frequencies in more common tumours including melanoma, colorectal, thyroid and lung carcinomas. Identifying NTRK fusions is a challenging task given the different genetic mechanisms underlying NTRK fusions, their varying frequency across different tumour types, complicated by other factors such as tissue availability, optimal detection methods, accessibility and costs of testing methods. Pathologists play a key role in navigating through these complexities by determining optimal approaches to NTRK testing which has important therapeutic and prognostic implications. This review provides an overview of tumours harbouring NTRK fusions, the importance of identifying these fusions, available testing methods including advantages and limitations, and generalised and tumour-specific approaches to testing.


Assuntos
Neoplasias da Mama , Carcinoma , Neoplasias , Humanos , Feminino , Receptor trkA/genética , Patologistas , Proteínas de Fusão Oncogênica/genética , Neoplasias/genética , Neoplasias/patologia , Fusão Gênica
4.
Hum Pathol ; 138: 41-48, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37245628

RESUMO

Cellular myofibromas/myopericytomas harboring recurring SRF fusions are recently characterized as rare and diagnostically challenging entities, which can mimic myogenic sarcomas. These tumors belong to the pericytic/perivascular myoid tumor family, which comprises a group of genetically heterogenous and sometimes morphologically overlapping entities. In this series, we describe 3 cases of SRF-rearranged cellular myofibromas/perivascular myoid tumors with a smooth muscle-like phenotype in children. The children ranged from 7 to 16 years of age, and all presented with a painless mass in the extremities, 2 of which were deep-seated. Histologically, the tumors demonstrated a smooth muscle-like morphology and immunophenotype with mild atypia and low-level mitotic activity. Prominent dense collagen deposition and coarse calcification was observed in 2 tumors. RNA sequencing revealed SRF fusions in all cases, with each tumor showing a different 3' partner gene, RELA, NFKBIE, and NCOA3. Of these, NCOA3 has not been reported previously, and this expands the molecular spectrum by identifying a novel fusion partner for SRF. Given that histological features can be worrisome for a myogenic sarcoma, wider awareness of this emerging tumor is valuable to avoid potential misclassification.


Assuntos
Miofibroma , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Extremidades , Miofibroma/genética , Recidiva Local de Neoplasia , Sarcoma/genética , Neoplasias de Tecidos Moles/genética
5.
Lancet Reg Health Southeast Asia ; 4: 100031, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35775040

RESUMO

Background: Tackling the spread of COVID-19 remains a crucial part of ending the pandemic. Its highly contagious nature and constant evolution coupled with a relative lack of immunity make the virus difficult to control. For this, various strategies have been proposed and adopted including limiting contact, social isolation, vaccination, contact tracing, etc. However, given the heterogeneity in the enforcement of these strategies and constant fluctuations in the strictness levels of these strategies, it becomes challenging to assess the true impact of these strategies in controlling the spread of COVID-19. Methods: In the present study, we evaluated various transmission control measures that were imposed in 10 global urban cities and provinces in 2021- Bangkok, Gauteng, Ho Chi Minh City, Jakarta, London, Manila City, New Delhi, New York City, Singapore, and Tokyo. Findings: Based on our analysis, we herein propose the population-level Swiss cheese model for the failures and pitfalls in various strategies that each of these cities and provinces had. Furthermore, whilst all the evaluated cities and provinces took a different personalized approach to managing the pandemic, what remained common was dynamic enforcement and monitoring of breaches of each barrier of protection. The measures taken to reinforce the barriers were adjusted continuously based on the evolving epidemiological situation. Interpretation: How an individual city or province handled the pandemic profoundly affected and determined how the entire country handled the pandemic since the chain of transmission needs to be broken at the very grassroot level to achieve nationwide control. Funding: The present study did not receive any external funding.

6.
Radiol Case Rep ; 17(1): 142-146, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34820038

RESUMO

Acute bilateral internal carotid occlusion was a very rare disease with a very poor prognosis. Clinical case reports according to the literature showed that mechanical thrombectomy was the most optimal treatment. We reported a clinical case of successful treatment with simultaneous thrombectomy in both occluded carotid arteries. A 62-year-old woman was admitted at our hospital within three hours of stroke onset secondary to an acute simultaneously bilateral carotid artery occlusion. On admission, her NIHSS (National Institutes of Health Stroke Scale) was 32. Non-contrast computed tomography right after that showed hyperacute infarction lesions in both hemispheres with right inferior temporal and insular cortex (Alberta Stroke Program Early CT Score - ASPECTS 8) and left putamen (ASPECTS 9). Her medical history included paroxysmal atrial fibrillation, prior ischemic stroke, pacemaker due to sick sinus syndrome. Her pre-stroke modified Rankin Scale score was 0 that she was fully recovered from previous stroke 4 months ago thanks to successful thrombectomy of the right internal carotid arteries (ICA). This time, the patient underwent again the simultaneous bilateral mechanical thrombectomy of both occluded ICA. The complete recanalization achieved on both sides with recanalization level of TICI-3 (thrombolysis in cerebral infarction) only in 38 mins after the groin puncture. She showed dramatic recovery and was discharged on day 28 with a Rankin Scale score of 2. Mechanical thrombectomy on bilateral ICA performed simultaneously will helps shorten the reperfusion time compared to the alternative one and thus, provides a better prognosis in acute ischemic stroke.

7.
J Med Humanit ; 42(4): 603-625, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34779996

RESUMO

INTRODUCTION: This study examines differences in students' perceived value of three artmaking modalities (poetry, comics, masks) and whether the resulting creative projects offer similar or different insights into medical students' professional identity formation. METHODS: Mixed-methods design using a student survey, student narrative comments and qualitative analysis of students' original work. RESULTS: Poetry and comics stimulated insight, but masks were more enjoyable and stress-reducing. All three art modalities expressed tension between personal and professional identities. DISCUSSION: Regardless of type of artmaking, students express concern about encroachments of training on personal identity but hoped that personal and professional selves could be integrated.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Máscaras , Narração , Identificação Social
8.
Small ; 17(45): e2103994, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34605163

RESUMO

The emergence of interlayer excitons (IEs) from atomic layered transition metal dichalcogenides (TMDCs) heterostructures has drawn tremendous attention due to their unique and exotic optoelectronic properties. Coupling the IEs into optical cavities provides distinctive electromagnetic environments which plays an important role in controlling multiple optical processes such as optical nonlinear generation or photoluminescence enhancement. Here, the integration of IEs in TMDCs into plasmonic nanocavities based on a nanocube on a metallic mirror is reported. Spectroscopic studies reveal an order of magnitude enhancement of the IE at room temperature and a 5-time enhancement in fluorescence at cryogenic temperatures. Cavity modeling reveals that the enhancement of the emission is attributed to both increased excitation efficiency and Purcell effect from the cavity. The results show a novel method to control the excitonic processes in TMDC heterostructures to build high performance photonics and optoelectronics devices.

9.
Environ Sci Process Impacts ; 23(10): 1458-1465, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34546240

RESUMO

The high proportion of unidentified extractable organofluorine (EOF) observed globally in humans and the environment indicates widespread occurrence of unknown per- and polyfluoroalkyl substances (PFAS). However, efforts to standardize or assess the reproducibility of EOF methods are currently lacking. Here we present the first EOF interlaboratory comparison in water and sludge. Three participants (four organizations) analyzed unfortified and PFAS-fortified ultrapure water, two unfortified groundwater samples, unfortified wastewater treatment plant effluent and sludge, and an unfortified groundwater extract. Participants adopted common sample handling strategies and target lists for EOF mass balance but used in-house combustion ion-chromatography (CIC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. EOF accuracy ranged from 85-101% and 76-109% for the 60 and 334 ng L-1 fluorine (F) - fortified water samples, respectively, with between-laboratory variation of 9-19%, and within-laboratory variation of 3-27%. In unfortified sludge and aqueous samples, between-laboratory variation ranged from 21-37%. The contribution from sum concentrations of 16 individual PFAS (∑PFAS-16) to EOF ranged from 2.2-60% but extended analysis showed that other targets were prevalent, in particular ultra-short-chain perfluoroalkyl acids (e.g. trifluoroacetic acid) in aqueous samples and perfluoroalkyl acid-precursors (e.g. polyfluoroalkyl phosphate diesters) in sludge. The EOF-CIC method demonstrated promising accuracy, robustness and reporting limits but poor extraction efficiency was observed for some targets (e.g. trifluoroacetic acid).


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Cromatografia Líquida , Flúor , Fluorocarbonos/análise , Humanos , Reprodutibilidade dos Testes , Esgotos , Espectrometria de Massas em Tandem , Água , Poluentes Químicos da Água/análise
10.
Pract Neurol ; 21(3): 237-240, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33574114

RESUMO

A 37-year-old woman developed progressive symmetrical weakness with areflexia, consistent with Guillain-Barré syndrome. After initially briefly responding to intravenous immunoglobulin, her weakness progressed markedly. Further investigation identified a new diagnosis of systemic lupus erythematosus with lupus nephritis. Following additional plasma exchange and corticosteroids, the lupus activity remitted and she made a complete neurological recovery.


Assuntos
Síndrome de Guillain-Barré , Lúpus Eritematoso Sistêmico , Adulto , Feminino , Síndrome de Guillain-Barré/complicações , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Troca Plasmática
11.
Nano Lett ; 19(8): 5417-5422, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31264881

RESUMO

Fluorescent nanoparticles with optically robust luminescence are imperative to applications in imaging and labeling. Here we demonstrate that hexagonal boron nitride (hBN) nanoparticles can be reliably produced using a scalable cryogenic exfoliation technique with sizes below 10 nm. The particles exhibit bright fluorescence generated by color centers that act as atomic-size quantum emitters. We analyze their optical properties, including emission wavelength, photon-statistics, and photodynamics, and show that they are suitable for far-field super-resolution fluorescence nanoscopy. Our results provide a foundation for exploration of hBN nanoparticles as candidates for bioimaging, labeling, as well as biomarkers that are suitable for quantum sensing.


Assuntos
Compostos de Boro/química , Nanopartículas/química , Temperatura Baixa , Fluorescência , Corantes Fluorescentes/química , Nanopartículas/ultraestrutura , Nanotecnologia/métodos , Tamanho da Partícula , Propriedades de Superfície
12.
Environ Int ; 130: 104921, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31229872

RESUMO

Consumer goods and building materials present in the preschool environment can be important sources of hazardous chemicals, such as plasticizers, bisphenols, organophosphorus and brominated flame retardants, poly- and perfluoroalkyl substances, which may pose a health risk to children. Even though exposure occurs via many different pathways, such as food intake, inhalation, dermal exposure, mouthing of toys etc., dust has been identified as a valuable indicator for indoor exposure. In the present study, we evaluate the efficiency of product substitution actions taken in 20 Swedish preschools from the Stockholm area to reduce the presence of hazardous substances in indoor environments. Dust samples were collected from elevated surfaces in rooms where children have their everyday activities, and the concentrations found were compared to the levels from a previous study conducted in 2015 at the same preschools. It was possible to lower levels of hazardous substances in dust, but their continued presence in the everyday environment of children was confirmed since bisphenol A, restricted phthalates and organophosphate esters were still detectable in all preschools. Also, an increase in the levels of some of the substitutes for the nowadays restricted substances was noted; some of the alternative plasticizers to phthalates, such as DEHA and DEHT, were found with increased concentrations. DINP was the dominant plasticizer in preschool dust with a median concentration of 389 µg/g, while its level was significantly (p = 0.012) higher at 716 µg/g in preschools with polyvinyl chloride (PVC) flooring. PBDEs were now less frequently detected in dust and their levels decreased 20% to 30%. This was one of the few times that PFAS were analyzed in preschool dust, where 6:2 diPAP was found to be most abundant with a median concentration of 1140 ng/g, followed by 6:2 PAP 151 ng/g, 8:2 diPAP 36 ng/g, N-Et-FOSAA 18 ng/g, PFOS 12 ng/g, PFOA 7.7 ng/g and PFNA 1.1 ng/g. In addition, fluorotelomer alcohols were detected in 65-90% of the samples. Children's exposure via dust ingestion was evaluated using intermediate and high daily intake rates of the targeted chemicals and established health limit values. In each case, the hazard quotients (HQs) were < 1, and the risk for children to have adverse health effects from the hazardous chemicals analyzed in this study via dust ingestion was even lower after the product substitution actions were taken in preschools.


Assuntos
Exposição Ambiental/análise , Retardadores de Chama/análise , Éteres Difenil Halogenados/química , Substâncias Perigosas/química , Organofosfatos/química , Instituições Acadêmicas , Poluição do Ar em Ambientes Fechados/análise , Compostos Benzidrílicos/química , Criança , Pré-Escolar , Poeira/análise , Monitoramento Ambiental/métodos , Pisos e Cobertura de Pisos , Halogenação , Humanos , Fenóis/química , Ácidos Ftálicos , Plastificantes/química , Jogos e Brinquedos , Suécia
13.
Sci Total Environ ; 625: 1046-1055, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29996401

RESUMO

Alternative flame retardants (FRs) have now replaced legacy FRs (such as polybrominated diphenyl ethers, PBDEs), but little is known about their fate in the aquatic environment. In this study, a range of legacy FRs (n=10) and alternative FRs, including halogenated FRs (HFRs, n=32) and organophosphorus FRs (OPFRs, n=19), were screened in water samples collected from 23 rivers covering the whole latitudinal range of Sweden. Of the 61 targeted FRs, 26 were detected in at least one of the river samples, with ΣFR concentrations ranging up to 170ngL-1 (mean 31±45ngL-1). In general, higher concentrations and a larger variety of FRs were detected in southern Sweden (ΣFR=60±56ngL-1) compared with the north (ΣFR=9.0±16ngL-1). In the south, HFRs were dominant, constituting on average 59% of ∑FRs, whereas in the north, OPFRs were dominant, constituting on average 82% of ∑FRs. This difference was best explained by higher population density in the south. The total daily flux of FRs into the Baltic Sea was estimated to be ~31kg and comprised mainly tetrabromobisphenol-A (TBBPA), 3,4,5,6-tetrabromophthalic anhydride (TEBP-Anh), and 2,4,6-tribromophenol (TBP). To the best of our knowledge, this is the first report of environmental occurrence of TEBP-Anh, which was detected in two rivers and is suggested to originate from airports located near the sampling sites.

14.
ACS Appl Mater Interfaces ; 10(29): 24886-24891, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29882642

RESUMO

Hexagonal boron nitride (hBN) mono and multilayers are promising hosts for room-temperature single photon emitters (SPEs). In this work we explore high-energy (∼MeV) electron irradiation as a means to generate stable SPEs in hBN. We investigate four types of exfoliated hBN flakes-namely, high-purity multilayers, isotopically pure hBN, carbon-rich hBN multilayers and monolayered material-and find that electron irradiation increases emitter concentrations dramatically in all samples. Furthermore, the engineered emitters are located throughout hBN flakes (not only at flake edges or grain boundaries) and do not require activation by high-temperature annealing of the host material after electron exposure. Our results provide important insights into controlled formation of hBN SPEs and may aid in identification of their crystallographic origin.

15.
Health Behav Policy Rev ; 4(2): 118-128, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28798944

RESUMO

OBJECTIVES: Interventions for colorectal cancer (CRC) prevention among black adults are needed. Connections between CRC screening non-adherence and other health risk behaviors may inform intervention development. METHODS: Associations between red meat (RM) and fruit and vegetable (FV) consumption, at-risk alcohol use, and CRC ever-screening were examined using adjusted logistic regressions among 520 church-going black adults in Houston, Texas, aged >50. RESULTS: In the final adjusted model, being younger, uninsured, eating more RM and engaging in at-risk alcohol use were associated with lower likelihood of CRC ever-screening. CONCLUSIONS: Church-based interventions to increase CRC screening among black adults might capitalize on associations with RM consumption and alcohol use behaviors as part of a broader wellness promotion initiative.

16.
Primates ; 58(3): 435-440, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28492971

RESUMO

Following the split of the silvered langurs of Indochina into two species based on molecular and phenotypic data, there is a need to reevaluate their distribution and update their conservation status. Here, we report the distribution and assess the population size of Germain's langur (Trachypithecus germaini) within its known range across Vietnam. We confirmed this species at six of seven survey sites in different habitats within three provinces in the Mekong Delta Region, including semi-evergreen forest at the Seven Mountains of An Giang Province, mangrove forest in Ngoc Hien and Nam Can Districts and Melaleuca forest in U Minh Ha National Park of Ca Mau Province, and limestone forest at Kien Luong Karst Area and semi-evergreen and evergreen forests at Phu Quoc National Park of Kien Giang Province. We found no evidence of this species in Mui Ca Mau National Park, Ca Mau Province where it was previously reported. We conservatively estimate that the total population of Germain's langurs in Vietnam consists of 362-406 individuals, with the largest population found in the Kien Luong Karst Area. Hunting and habitat loss are severely impacting Germain's langur, resulting in the extirpation of the population in Mui Ca Mau National Park and small, isolated populations in the Seven Mountains and Ngoc Hien and Nam Can Districts. However, the ability of this species to inhabit a wide range of forest types, and its increasing population sizes in Phu Quoc National Park and Kien Luong Karst Area, provide signs of hope that continued conservation actions may help in its long-term survival.


Assuntos
Cercopithecidae , Colobinae , Conservação dos Recursos Naturais , Animais , Ecossistema , Florestas , Vietnã
17.
Drug Alcohol Depend ; 153: 341-5, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26072221

RESUMO

INTRODUCTION: Homeless individuals smoke at disproportionately high rates and quit at disproportionately low rates relative to domiciled smokers. Targeted research is needed to inform future interventions. Socio-demographic characteristics of homeless adults suggest that light smoking may be prevalent, and the relation between smoking level and treatment-related preferences/needs is unknown. The current study addressed these gaps in a sample of homeless smokers. METHODS: Participants (N=237) were homeless adult daily light (1-10 cigarettes per day) and moderate/heavy (>10 cigarettes per day) smokers recruited from a single shelter that offered cessation treatment. Survey items assessed perceived treatment effectiveness, pharmacological intervention preferences, and barriers to quitting smoking. Logistic regressions were used to assess differences in treatment-related factors by smoking level. RESULTS: The prevalence of light smoking (44.7%) was higher than in previously studied samples of domiciled smokers. Relative to moderate/heavy smokers, light smokers smoked for fewer years, had more quit attempts in the last year, and were more likely to smoke menthol cigarettes. They were less likely to believe that medications would give them the greatest chance of quitting and more likely to believe that group counseling would be helpful. Light smokers did not differ from moderate/heavy smokers on specific pharmacological intervention preferences or on perceived barriers to quitting smoking, including craving. CONCLUSIONS: The promotion of pharmacotherapy to address cravings may be necessary for light smokers, who represent a sizeable proportion of homeless smokers and who may make apt intervention targets given their higher rates of purposeful quit attempts relative to heavier smoking counterparts.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoas Mal Alojadas/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Resultado do Tratamento , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
18.
Am J Health Behav ; 39(1): 14-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25290593

RESUMO

OBJECTIVE: To examine the association between subjective sleep inadequacy and self-rated health in a sample of 244 homeless adults. METHODS: Logistic regression analyses were conducted to assess associations among 4 sleep inadequacy items (days of inadequate rest or sleep, hours of sleep, days unintentionally falling asleep during daytime, and snoring) and self-rated health in analyses adjusted for age, sex, race, education, lifetime homelessness, lifetime serious mental illness, and current depression. RESULTS: Days of inadequate rest or sleep, fewer hours of sleep, and days unintentionally falling asleep were each significantly associated with higher odds of poor/fair self-rated health. CONCLUSION: Because both inadequate sleep and poor self-rated health independently predict mortality, interventions targeting sleep quality among homeless adults are needed.


Assuntos
Nível de Saúde , Pessoas Mal Alojadas/psicologia , Autorrelato , Distúrbios do Início e da Manutenção do Sono/psicologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
19.
Mol Biol Evol ; 30(5): 1188-95, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23418397

RESUMO

Nonparametric bootstrap has been a widely used tool in phylogenetic analysis to assess the clade support of phylogenetic trees. However, with the rapidly growing amount of data, this task remains a computational bottleneck. Recently, approximation methods such as the RAxML rapid bootstrap (RBS) and the Shimodaira-Hasegawa-like approximate likelihood ratio test have been introduced to speed up the bootstrap. Here, we suggest an ultrafast bootstrap approximation approach (UFBoot) to compute the support of phylogenetic groups in maximum likelihood (ML) based trees. To achieve this, we combine the resampling estimated log-likelihood method with a simple but effective collection scheme of candidate trees. We also propose a stopping rule that assesses the convergence of branch support values to automatically determine when to stop collecting candidate trees. UFBoot achieves a median speed up of 3.1 (range: 0.66-33.3) to 10.2 (range: 1.32-41.4) compared with RAxML RBS for real DNA and amino acid alignments, respectively. Moreover, our extensive simulations show that UFBoot is robust against moderate model violations and the support values obtained appear to be relatively unbiased compared with the conservative standard bootstrap. This provides a more direct interpretation of the bootstrap support. We offer an efficient and easy-to-use software (available at http://www.cibiv.at/software/iqtree) to perform the UFBoot analysis with ML tree inference.


Assuntos
Funções Verossimilhança , Simulação por Computador , Filogenia
20.
Algorithms Mol Biol ; 7(1): 36, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23241267

RESUMO

Recently one step mutation matrices were introduced to model the impact of substitutions on arbitrary branches of a phylogenetic tree on an alignment site. This concept works nicely for the four-state nucleotide alphabet and provides an efficient procedure conjectured to compute the minimal number of substitutions needed to transform one alignment site into another. The present paper delivers a proof of the validity of this algorithm. Moreover, we provide several mathematical insights into the generalization of the OSM matrix to multi-state alphabets. The construction of the OSM matrix is only possible if the matrices representing the substitution types acting on the character states and the identity matrix form a commutative group with respect to matrix multiplication. We illustrate this approach by looking at Abelian groups over twenty states and critically discuss their biological usefulness when investigating amino acids.

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