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1.
Science ; 384(6692): 214-217, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38603482

RESUMO

Massive stars (those ≥8 solar masses at formation) have radiative envelopes that cannot sustain a dynamo, the mechanism that produces magnetic fields in lower-mass stars. Despite this, approximately 7% of massive stars have observed magnetic fields, the origin of which is debated. We used multi-epoch interferometric and spectroscopic observations to characterize HD 148937, a binary system of two massive stars. We found that only one star is magnetic and that it appears younger than its companion. The system properties and a surrounding bipolar nebula can be reproduced with a model in which two stars merged (in a previous triple system) to produce the magnetic massive star. Our results provide observational evidence that magnetic fields form in at least some massive stars through stellar mergers.

2.
Asian Pac J Cancer Prev ; 23(2): 601-615, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35225473

RESUMO

INTRODUCTION: There are limited published data regarding the recent incidence trends of cancer in Iraqi Kurdistan. METHODS: The present study assessed the epidemiological estimates of cancer incidence, as well providing a projection of future cancer trends in the upcoming decade by analysing the population-based cancer registry between 2013 and 2019, in both the Erbil and Duhok governorates. A retrospective analysis was performed on data retrieved from the Medical Statistics Department at the Ministry of Health, Kurdistan Regional Government (KRG). RESULTS: The total number of female cancer patients was higher in both governorates, and the total incidence of patients with cancer increased by over 2x between 2013 and 2019 in Erbil and Duhok, from 73 to 174 patients/100,000 individuals for women, and 36 to 85 patients/100,000 individuals for men. Analysis indicated that the percentage of patients with cancer is projected to increase by >2x in the current decade, from 3,457 cases to 4,547 and 4,449 cases in the Erbil governorate; and from 1,365 to 2,633 and 2,737 cases in 2028 based on LSTM and bi-LTSM analysis in the Duhok governorate. Lung cancer (LC) and female breast cancer (BC) were the most prominent types of cancers diagnosed since 2013 in both the Erbil and Duhok governorates. CONCLUSION: The striking pattern of trends for both present and future cancer incidence rates require urgent solutions and comprehensive efforts to control risk factors that promote the increasing incidence of cancer in these two KRG governorates.
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Assuntos
Neoplasias/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Iraque/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Distribuição por Sexo , Adulto Jovem
3.
Science ; 361(6397): 88-92, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29976827

RESUMO

The human occupation history of Southeast Asia (SEA) remains heavily debated. Current evidence suggests that SEA was occupied by Hòabìnhian hunter-gatherers until ~4000 years ago, when farming economies developed and expanded, restricting foraging groups to remote habitats. Some argue that agricultural development was indigenous; others favor the "two-layer" hypothesis that posits a southward expansion of farmers giving rise to present-day Southeast Asian genetic diversity. By sequencing 26 ancient human genomes (25 from SEA, 1 Japanese Jomon), we show that neither interpretation fits the complexity of Southeast Asian history: Both Hòabìnhian hunter-gatherers and East Asian farmers contributed to current Southeast Asian diversity, with further migrations affecting island SEA and Vietnam. Our results help resolve one of the long-standing controversies in Southeast Asian prehistory.


Assuntos
Genoma Humano , Migração Humana/história , Sudeste Asiático , Povo Asiático/genética , DNA Antigo , Variação Genética , História Antiga , Humanos , População/genética , Análise de Sequência de DNA
4.
Curr Med Mycol ; 3(1): 1-5, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29302623

RESUMO

BACKGROUND AND PURPOSE: Cladosporium species are ubiquitous, saprobic, dematiaceous fungi, only infrequently associated with human and animal opportunistic infections. MATERIALS AND METHODS: Airborne samples were collected using the settle plate method, and soil samples were obtained from a depth of 5-10 cm of the superficial soil layer. Samples were cultured on Sabouraud dextrose agar (SDA) plates, incubated at 25°C, and examined daily for fungal colonies for two to three weeks. Isolates were identified as Cladosporium species according to the macroscopic and microscopic criteria. For species differentiation, DNA from 53 isolates was extracted and subjected to amplification of the internal transcribed spacer (ITS) region followed by sequencing. RESULTS: A total of 270 samples were collected from various environmental sources, of which 79 strains of Cladosporium species were isolated. The most frequent species was C. cladosporioides (50.6%), followed by C. iridis (44.3%), C. elatum (2.5%), C. peranqestum (1.3%), and C. alicinum (1.3%). CONCLUSION: The collected data can serve as baseline information for future research and may be useful in the development of preventive and educational strategies.

5.
Nature ; 538(7624): 207-214, 2016 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-27654914

RESUMO

The population history of Aboriginal Australians remains largely uncharacterized. Here we generate high-coverage genomes for 83 Aboriginal Australians (speakers of Pama-Nyungan languages) and 25 Papuans from the New Guinea Highlands. We find that Papuan and Aboriginal Australian ancestors diversified 25-40 thousand years ago (kya), suggesting pre-Holocene population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all of the studied Aboriginal Australians descend from a single founding population that differentiated ~10-32 kya. We infer a population expansion in northeast Australia during the Holocene epoch (past 10,000 years) associated with limited gene flow from this region to the rest of Australia, consistent with the spread of the Pama-Nyungan languages. We estimate that Aboriginal Australians and Papuans diverged from Eurasians 51-72 kya, following a single out-of-Africa dispersal, and subsequently admixed with archaic populations. Finally, we report evidence of selection in Aboriginal Australians potentially associated with living in the desert.


Assuntos
Genoma Humano/genética , Genômica , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , Filogenia , Grupos Raciais/genética , África/etnologia , Austrália , Conjuntos de Dados como Assunto , Clima Desértico , Fluxo Gênico , Genética Populacional , História Antiga , Migração Humana/história , Humanos , Idioma , Nova Guiné , Dinâmica Populacional , Tasmânia
6.
Rev Sci Instrum ; 84(3): 033107, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23556807

RESUMO

The construction, alignment, and performance of a setup for broadband wide-angle dispersion measurements, with emphasis on surface plasmon resonance (SPR) measurements, are presented in comprehensive detail. In contrast with most SPR instruments working with a monochromatic source, this setup takes advantage of a broadband∕white light source and has full capability for automated angle vs. wavelength dispersion measurements for any arbitrary nanostructure array. A cylindrical prism is used rather than a triangular one in order to mitigate refraction induced effects and allow for such measurements. Although seemingly simple, this instrument requires use of many non-trivial methods in order to achieve proper alignment over all angles of incidence. Here we describe the alignment procedure for such a setup, the pitfalls introduced from the finite beam width incident onto the cylindrical prism, and deviations in the reflected∕transmitted beam resulting from the finite thickness of the sample substrate. We address every one of these issues and provide experimental evidences on the success of this instrument and the alignment procedure used.


Assuntos
Refratometria/instrumentação , Refratometria/métodos , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Desenho de Equipamento , Ouro/química , Lasers , Luz , Software , Propriedades de Superfície
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