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1.
Nature ; 598(7880): 272-275, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34646001

RESUMO

Studies1,2 have shown that the remnants of destroyed planets and debris-disk planetesimals can survive the volatile evolution of their host stars into white dwarfs3,4, but few intact planetary bodies around white dwarfs have been detected5-8. Simulations predict9-11 that planets in Jupiter-like orbits around stars of ≲8 M☉ (solar mass) avoid being destroyed by the strong tidal forces of their stellar host, but as yet, there has been no observational confirmation of such a survivor. Here we report the non-detection of a main-sequence lens star in the microlensing event MOA-2010-BLG-477Lb12 using near-infrared observations from the Keck Observatory. We determine that this system contains a 0.53 ± 0.11 M☉ white-dwarf host orbited by a 1.4 ± 0.3 Jupiter-mass planet with a separation on the plane of the sky of 2.8 ± 0.5 astronomical units, which implies a semi-major axis larger than this. This system is evidence that planets around white dwarfs can survive the giant and asymptotic giant phases of their host's evolution, and supports the prediction that more than half of white dwarfs have Jovian planetary companions13. Located at approximately 2.0 kiloparsecs towards the centre of our Galaxy, it is likely to represent an analogue to the end stages of the Sun and Jupiter in our own Solar System.

2.
Nanotechnology ; 32(4): 042003, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33155576

RESUMO

This roadmap on Nanotechnology for Catalysis and Solar Energy Conversion focuses on the application of nanotechnology in addressing the current challenges of energy conversion: 'high efficiency, stability, safety, and the potential for low-cost/scalable manufacturing' to quote from the contributed article by Nathan Lewis. This roadmap focuses on solar-to-fuel conversion, solar water splitting, solar photovoltaics and bio-catalysis. It includes dye-sensitized solar cells (DSSCs), perovskite solar cells, and organic photovoltaics. Smart engineering of colloidal quantum materials and nanostructured electrodes will improve solar-to-fuel conversion efficiency, as described in the articles by Waiskopf and Banin and Meyer. Semiconductor nanoparticles will also improve solar energy conversion efficiency, as discussed by Boschloo et al in their article on DSSCs. Perovskite solar cells have advanced rapidly in recent years, including new ideas on 2D and 3D hybrid halide perovskites, as described by Spanopoulos et al 'Next generation' solar cells using multiple exciton generation (MEG) from hot carriers, described in the article by Nozik and Beard, could lead to remarkable improvement in photovoltaic efficiency by using quantization effects in semiconductor nanostructures (quantum dots, wires or wells). These challenges will not be met without simultaneous improvement in nanoscale characterization methods. Terahertz spectroscopy, discussed in the article by Milot et al is one example of a method that is overcoming the difficulties associated with nanoscale materials characterization by avoiding electrical contacts to nanoparticles, allowing characterization during device operation, and enabling characterization of a single nanoparticle. Besides experimental advances, computational science is also meeting the challenges of nanomaterials synthesis. The article by Kohlstedt and Schatz discusses the computational frameworks being used to predict structure-property relationships in materials and devices, including machine learning methods, with an emphasis on organic photovoltaics. The contribution by Megarity and Armstrong presents the 'electrochemical leaf' for improvements in electrochemistry and beyond. In addition, biohybrid approaches can take advantage of efficient and specific enzyme catalysts. These articles present the nanoscience and technology at the forefront of renewable energy development that will have significant benefits to society.

3.
Eur J Prosthodont Restor Dent ; 29(2): 76-83, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33146474

RESUMO

This study aimed to assess the effects of splinting in 3-unit implant-supported prostheses with varying the splinting factor, length of the implant, and the diameter of the 1°molar (1°M) implant on cortical bone tissue (CBT). Twelve 3D models were simulated, which represented the posterior maxillary with 3 implants, supporting 3-unit FDP varying the splinting factor (single-unit crowns, splinted crowns straight-line and offset implant configuration [OIC]), length of the implant (7mm and 8,5mm), and the diameter of the 1°M (Ø4 mm and Ø5 mm). The CBT was analyzed by maximum principal stress and microstrain maps. The increase in implant diameter improved the biomechanical behavior of rehabilitation. The increase of the implant diameter in the 1°M associated with OIC generated the best biomechanical behavior for CBT. The splinting was effective in decreasing stress and microstrain, mainly when associated with OIC and implant diameter of Ø5 in the 1°M. The effect of increasing the diameter of the implant referring to the 1°M for single-unit crowns was more effective than the effect of the splinting of implants with Ø4 mm in straight-line. The diameter and splinting factors showed to be more important than implant length to reduce the stress and microstrain on CBT.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Fenômenos Biomecânicos , Coroas , Planejamento de Prótese Dentária , Análise do Estresse Dentário , Análise de Elementos Finitos , Estresse Mecânico
4.
Nature ; 481(7380): 167-9, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22237108

RESUMO

Most known extrasolar planets (exoplanets) have been discovered using the radial velocity or transit methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17-30% (refs 4, 5) of solar-like stars host a planet. Gravitational microlensing, on the other hand, probes planets that are further away from their stars. Recently, a population of planets that are unbound or very far from their stars was discovered by microlensing. These planets are at least as numerous as the stars in the Milky Way. Here we report a statistical analysis of microlensing data (gathered in 2002-07) that reveals the fraction of bound planets 0.5-10 AU (Sun-Earth distance) from their stars. We find that 17(+6)(-9)% of stars host Jupiter-mass planets (0.3-10 M(J), where M(J) = 318 M(⊕) and M(⊕) is Earth's mass). Cool Neptunes (10-30 M(⊕)) and super-Earths (5-10 M(⊕)) are even more common: their respective abundances per star are 52(+22)(-29)% and 62(+35)(-37)%. We conclude that stars are orbited by planets as a rule, rather than the exception.

5.
J Fish Biol ; 89(1): 847-62, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27278251

RESUMO

This study assessed the influence of the seasonal fluctuation of abiotic conditions (wet v. dry season) on the functional diversity (FD) of tropical coastal fish assemblages. Sampling was carried out in three regions of north-east Brazil with contrasting coastlines (influenced by reef, lagoon and estuary). In each region, fishes were sampled from three depth strata (10, 20 and 30 m) and FD was estimated using an index based on key phenotypic and behavioural characteristics. All three regions had higher FD in the wet season at shallower depths, indicating the coexistence of species with low functional redundancy in sites subject to seasonal flushing of fresh water. Deeper sites had lower FD than shallower sites, although this difference was less pronounced for region 3, which is strongly affected by its proximity to the São Francisco estuary. The results broadly support the hypothesis that alterations in abiotic conditions in the wet season allow estuarine-adapted fishes with a different suite of functional traits to invade shallow coastal regions.


Assuntos
Ecossistema , Estuários , Peixes , Animais , Brasil , Água Doce , Estações do Ano
6.
Genet Mol Res ; 14(3): 7386-94, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26214417

RESUMO

Gene sequences previously identified in Arabidopsis buds were used as references in order to estimate temporal and tissue expression in buds, leaves, stem, and root tissues in cotton plants. Buds were evaluated during 3 phases: 2-8, 10-12, and 14-20 mm. Primers were designed for the ARF6, ATFY, and SEUSS genes for use in semi-quantitative reverse transcription-polymerase chain reaction and quantitative reverse transcription-polymerase chain reaction. Different levels of expression of the 3 genes were confirmed in cotton buds as well as in other tissues. The peak of gene expression was observed in buds sized 10-12 mm, after which expression decreased in larger buds. The gene GhFYPP3 was the most promising for further prospection of promoter regions, with regular expression patterns observed in bud sizes 10-12 and 14-20 mm. This trait was not observed in others genes.


Assuntos
Gossypium/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Análise Espaço-Temporal , Transcriptoma
7.
Phys Chem Chem Phys ; 16(31): 16629-41, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24993024

RESUMO

An efficient synthetic protocol to functionalize the cyanoacrylic acid anchoring group of commercially available MK-2 dye with a highly water-stable hydroxamate anchoring group is described. Extensive characterization of this hydroxamate-modified dye (MK-2HA) reveals that the modification does not affect its favorable optoelectronic properties. Dye-sensitized solar cells (DSSCs) prepared with the MK-2HA dye attain improved efficiency (6.9%), relative to analogously prepared devices with commercial MK-2 and N719 dyes. The hydroxamate anchoring group also contributes to significantly increased water stability, with a decrease in the rate constant for dye desorption of MK-2HA relative to MK-2 in the presence of water by as much as 37.5%. In addition, the hydroxamate-anchored dye undergoes essentially no loss in DSSC efficiency and the external quantum efficiency improves when up to 20% water is purposefully added to the electrolyte. In contrast, devices prepared with the commercial dye suffer a 50% decline in efficiency under identical conditions, with a concomitant decrease in external quantum efficiency. Collectively, our results indicate that covalent functionalization of organic dyes with hydroxamate anchoring groups is a simple and efficient approach to improving the water stability of the dye-semiconductor interface and overall device durability.

8.
Med Vet Entomol ; 27(3): 247-54, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22985051

RESUMO

Triatoma brasiliensis (Hemiptera: Reduviidae) is an important vector of Chagas' disease in both sylvatic and peridomestic ecotopes. Discriminating between these populations of Triatominae has been proposed as a means of investigating re-infestation rates of human dwellings. Geometric morphometrics have been widely applied in the study of Triatominae polymorphisms at species and population levels. This study characterizes morphometric differences between sylvatic and peridomestic populations, as well as between sexes in T. brasiliensis specimens from Jaguaruana, Ceará, in northeastern Brazil. No differences in either the shape or size of the cephalic capsule were apparent between sexes or ecotopes. However, the wings showed differentiation in shape and size. Sexual dimorphism was detected, with females presenting significantly higher values and conformations. Size differentiation was also evident, with sylvatic specimens being generally larger than peridomestic examples. These results indicate that differences in the wings of T. brasiliensis may be related to the existence of phenotypic plasticity, and variations in size and shape may be associated with different ecotopes, possibly as a result of conditions in each micro-habitat, such as temperature, relative humidity, food supply and density.


Assuntos
Insetos Vetores/anatomia & histologia , Insetos Vetores/fisiologia , Triatoma/anatomia & histologia , Triatoma/fisiologia , Adaptação Fisiológica , Animais , Brasil , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Meio Ambiente , Feminino , Cabeça/anatomia & histologia , Insetos Vetores/genética , Masculino , Fenótipo , Análise de Componente Principal , Caracteres Sexuais , Triatoma/genética , Asas de Animais/anatomia & histologia
9.
Genet Mol Res ; 12(1): 37-43, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23359022

RESUMO

A subtractive cDNA library from cotton buds was constructed to prospect for differentially expressed genes related to early bud development. A library was constructed and 768 cDNA sequences were obtained, comprising 168 clusters, with 126 contigs and 42 singlets. Both the Gossypium as well as Arabidopsis databases were utilized for the in silico analysis, since some genes identified in cotton have not yet been studied for functionality, although they have homology with genes from other species. The transcriptome revealed a large number of transcripts, some of them with unknown function, and others related to pollen development, pollen tubes, ovules, and fibers at different stages. The most populated contig was identified as fiber from 0-10 days after anthesis, with 12 reads. The success and novelty rates generated from the library were 67 and 51%, respectively. The information obtained here will provide a framework for research on functional cotton genomics.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes de Plantas , Gossypium/crescimento & desenvolvimento , Gossypium/genética , Fibra de Algodão , DNA Complementar/genética , Biblioteca Gênica , Transcriptoma/genética
10.
Radiother Oncol ; 173: 188-196, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35661677

RESUMO

Surface guidance systems enable patient positioning and motion monitoring without using ionising radiation. Surface Guided Radiation Therapy (SGRT) has therefore been widely adopted in radiation therapy in recent years, but guidelines on workflows and specific quality assurance (QA) are lacking. This ESTRO-ACROP guideline aims to give recommendations concerning SGRT roles and responsibilities and highlights common challenges and potential errors. Comprehensive guidelines for procurement, acceptance, commissioning, and QA of SGRT systems installed on computed tomography (CT) simulators, C-arm linacs, closed-bore linacs, and particle therapy treatment systems are presented that will help move to a consensus among SGRT users and facilitate a safe and efficient implementation and clinical application of SGRT.


Assuntos
Radioterapia Guiada por Imagem , Humanos , Aceleradores de Partículas , Posicionamento do Paciente , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X/métodos
11.
Artigo em Inglês | MEDLINE | ID: mdl-35402740

RESUMO

Introduction: Surface Guided Radiation Therapy (SGRT) is being increasingly implemented into clinical practice across a number of techniques and irradiation-sites. This technology, which is provided by different vendors, can be used with most simulation- and delivery-systems. However, limited guidelines and the complexity of clinical settings have led to diverse patterns of operation. With the aim to understand current clinical practice a survey was designed focusing on specifics of the clinical implementation and usage. Materials and methods: A 32-question survey covered: type and number of systems, quality assurance (QA), clinical workflows, and identification of strengths/limitations. Respondents from different professional groups and countries were invited to participate. The survey was distributed internationally via ESTRO-membership, social media and vendors. Results: Of the 278 institutions responding, 172 had at least one SGRT-system and 136 use SGRT clinically. Implementation and QA were primarily based on the vendors' recommendations and phantoms. SGRT was mainly implemented in breast RT (116/136), with strong but diverse representation of other sites. Many (58/135) reported at least partial elimination of skin-marks and a third (43/126) used open-masks. The most common imaging protocol reported included the combination of radiographic imaging with SGRT. Patient positioning (115/136), motion management (104/136) and DIBH (99/136) were the main applications.Main barriers to broader application were cost, system integration issues and lack of demonstrated clinical value. A lack of guidelines in terms of QA of the system was highlighted. Conclusions: This overview of the SGRT status has the potential to support users, vendors and organisations in the development of practices, products and guidelines.

12.
Int J Oral Maxillofac Surg ; 50(5): 674-682, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33158693

RESUMO

The aim of this systematic review and meta-analysis was to evaluate studies comparing implant survival rates, marginal bone loss (MBL), and mechanical and biological complication rates between narrow-diameter implants (NDIs) and regular-diameter implants (RDIs) used for oral rehabilitation in the anterior region. The review was conducted according to the PRISMA checklist. Two independent reviewers performed a comprehensive search of the PubMed/MEDLINE, Embase, Scopus, and Cochrane Library databases for studies published until May 2020. A total of 843 implants (484 NDIs and 359 RDIs) were included. No significant difference in implant survival rate (risk difference (RD) 0.01, 95% confidence interval (CI) -0.01 to 0.03; P=0.34), MBL (standardised mean difference -0.51mm, 95% CI -1.29 to 0.26mm; P=0.19), mechanical complications (RD 0.01, 95% CI -0.02 to 0.04; P=0.40), or biological complications (RD 0.01, 95% CI -0.09 to 0.11; P=0.85) was found between the implant groups. Within the limitations of this study, it is concluded that NDIs are an effective alternative to RDIs due to similar survival rates, MBL, and mechanical and biological complication rates. However, future studies are highly encouraged due to the small number of interventional studies on this topic.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Humanos
13.
Mater Sci Eng C Mater Biol Appl ; 121: 111815, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33579459

RESUMO

This work deals with two new molecule-based materials, namely NiII-complexes of general formulae [Ni(L1)2] (Ni1) and [Ni(L2)2] (Ni2), where L1 = trans-cinnamaldehyde-N(4)-methyl thiosemicarbazone and L2 = trans-cinnamaldehyde-N(4)-ethyl thiosemicarbazone, as potential antitumor agents. Both compounds were characterized by elemental analysis, molar conductivity and spectroscopic techniques (FTIR and NMR). Their molecular structures were obtained by single-crystal X-ray diffraction analysis. Each one crystallizes in a monoclinic space group P 21/c, also the asymmetric unit comprises of one NiII ion located on an inversion centre and one anionic ligand, which acts as a κ2N,S-donor affording a five-membered metallaring. The compounds were screened against two selected tumour cell lines (MCF-7 and A549) and non-tumour fibroblasts cell line (MRC-5) via MTT assays. In both tumour cells, all compounds exhibited higher cytotoxicity than the control drug (cisplatin). The IC50 values ranges of 3.70 - 41.37 µM and 1.06 - 14.91 µM were found for MCF-7 and A549, respectively. Importantly, all of them were less toxicity than cisplatin in MRC-5 with SI values ranged at 11.80 - 86.60. The red blood cell (RBC) assay revealed Ni2 as non-toxic due to its reduced haemolytic effect (0--9% at 1--10 µM). The DNA binding was investigated through a combination of spectrophotometric absorption and emission titrations, electrophoresis, and circular dichroism experiments. As a result, these metal complexes were not able to strongly binding to DNA (Kb values ~104 mol L--1) but suggesting groove-binding interactions. The scavenging ability of them towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical was also evaluated in this work, but no important antioxidant behaviour was detected. Further, the interaction of Ni1 and Ni2 to human serum albumin (HSA) was explored by quenching of tryptophan emission, warfarin competitive assay, and molecular docking protocols. The HSA binding analyses indicated good affinity of both complexes to Sudlow site I (Kb values ⁓103 mol L-1).


Assuntos
Antineoplásicos , Complexos de Coordenação , Tiossemicarbazonas , Antineoplásicos/farmacologia , Humanos , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular
14.
J Fish Biol ; 76(9): 2118-76, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20557657

RESUMO

Fish conservation in South America is a pressing issue. The biodiversity of fishes, just as with all other groups of plants and animals, is far from fully known. Continuing habitat loss may result in biodiversity losses before full species diversity is known. In this review, the main river basins of South America (Magdalena, Orinoco, Amazon and Paraná-La Plata system), together with key aquatic habitats (mangrove-fringed estuaries of the tropical humid, tropical semi-arid and subtropical regions) are analysed in terms of their characteristics and main concerns. Habitat loss was the main concern identified for all South American ecosystems. It may be caused by damming of rivers, deforestation, water pollution, mining, poor agricultural practice or inadequate management practice. Habitat loss has a direct consequence, which is a decrease in the availability of living resources, a serious social and economic issue, especially for South American nations which are all developing countries. The introduction of exotic species and overfishing were also identified as widespread across the continent and its main freshwater, coastal and marine ecosystems. Finally, suggestions are made to find ways to overcome these problems. The main suggestion is a change of paradigm and a new design for conservation actions, starting with integrated research and aiming at the co-ordinated and harmonized management of the main transboundary waters of the continent. The actions would be focused on habitat conservation and social rescue of the less well-off populations of indigenous and non-indigenous peoples. Energy and freshwater demands will also have to be rescaled in order to control habitat loss.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Peixes , Animais , Biodiversidade , Pesqueiros , Peixes/genética , Geografia , Rios , América do Sul , Clima Tropical , Poluição da Água
15.
Radiat Oncol ; 15(1): 244, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33099305

RESUMO

An amendment to this paper has been published and can be accessed via the original article.

16.
Radiat Oncol ; 15(1): 187, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736570

RESUMO

The growing acceptance and recognition of Surface Guided Radiation Therapy (SGRT) as a promising imaging technique has supported its recent spread in a large number of radiation oncology facilities. Although this technology is not new, many aspects of it have only recently been exploited. This review focuses on the latest SGRT developments, both in the field of general clinical applications and special techniques.SGRT has a wide range of applications, including patient positioning with real-time feedback, patient monitoring throughout the treatment fraction, and motion management (as beam-gating in free-breathing or deep-inspiration breath-hold). Special radiotherapy modalities such as accelerated partial breast irradiation, particle radiotherapy, and pediatrics are the most recent SGRT developments.The fact that SGRT is nowadays used at various body sites has resulted in the need to adapt SGRT workflows to each body site. Current SGRT applications range from traditional breast irradiation, to thoracic, abdominal, or pelvic tumor sites, and include intracranial localizations.Following the latest SGRT applications and their specifications/requirements, a stricter quality assurance program needs to be ensured. Recent publications highlight the need to adapt quality assurance to the radiotherapy equipment type, SGRT technology, anatomic treatment sites, and clinical workflows, which results in a complex and extensive set of tests.Moreover, this review gives an outlook on the leading research trends. In particular, the potential to use deformable surfaces as motion surrogates, to use SGRT to detect anatomical variations along the treatment course, and to help in the establishment of personalized patient treatment (optimized margins and motion management strategies) are increasingly important research topics. SGRT is also emerging in the field of patient safety and integrates measures to reduce common radiotherapeutic risk events (e.g. facial and treatment accessories recognition).This review covers the latest clinical practices of SGRT and provides an outlook on potential applications of this imaging technique. It is intended to provide guidance for new users during the implementation, while triggering experienced users to further explore SGRT applications.


Assuntos
Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Dosagem Radioterapêutica
17.
Res Vet Sci ; 131: 222-231, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32413795

RESUMO

Skin lesions are normal to all species, regardless of gender or age. The skin, the largest organ of the body, has function as a primary barrier to the chemical, physical and biological aggressions of the environment. In animals, these lesions may be due to fights and/or predations, also as in humans, there is a very common cause of dermal lesions that are caused by burns and carcinomas. Looking for new techniques of tissue bioengineering, studies have been shown promising results for formulations of acellular biological scaffolds from tissue decellularization for the reconstitution of these lesions. The decellularization has its proof by a varied range of tests such as scanning electron microscopy and residual genomic DNA tests. Subsequently the tissue can go through the process of recellularization using cells of interest, even the animal that will receive this tissue, reducing the risks of rejection and improving the response to tissue transplantation. Thus, this manuscript aimed at the decellularization of the tissue with the use of chemical and physical means followed by sterilization and the establishment of a protocol for the recellularization of a decellularized scaffold from the Wistar rat dermis using murine fibroblasts and mesenchymal stem cells from canine adipose tissue for 7 days. After efficacy tests, the tissue recellularization were confirmed by immunofluorescence assays and scanning electron microscopy where the adherence of the cells in the biological scaffold was observed.


Assuntos
Derme , Fibroblastos/fisiologia , Células-Tronco Mesenquimais/fisiologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Cães , Camundongos , Ratos , Ratos Wistar
18.
Science ; 243(4887): 37-44, 1989 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-17780421

RESUMO

In 1986 more than 8 million liters of crude oil spilled into a complex region of mangroves, seagrasses, and coral reefs just east of the Caribbean entrance to the Panama Canal. This was the largest recorded spill into coastal habitats in the tropical Americas. Many population of plants and animals in both oiled and unoiled sites had been studied previously, thereby providing an unprecedented measure of ecological variation before the spill. Documenation of the spread of oil and its biological begun immediately. Intertidal mangroves, algae, and associated invertebrates were covered by oil and died soon after. More surprisingly, there was also extensive mortality of shallow subtidal reef corals and infauna of seagrass beds. After 1.5 years only some organisms in areas exposed to the open sea have recovered.

19.
Semergen ; 45(6): 406-412, 2019 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-30591385

RESUMO

OBJECTIVE: For cancer incidence, tobacco use is one of the main avoidable risk factors.The aim of this study is to describe the frequency, trend and geographical distribution of the incidence of tobacco-associated tumours in the León Health Area, Spain. MATERIAL AND METHODS: An observational, descriptive study was carried out on tumours of Hospital Registry of Tumours of the University Hospital Complex of León between 1997 and 2014. León Health Area residents, associated with smoking were included. Gross and adjusted rates were calculated and adjusted for triennials. For the analysis of spatial distribution, municipal relative hazards were smoothed by adjusting the Besag, York, and Mollié model and for their posterior probabilities for relative hazards to be higher than 1, using Bayesian methods. RESULTS: A total of 7,103 cases were included. Crude incidence rates rose from 116.4 (1997-1999) to 228.0 (2012-2014) per 100,000 men, and from 19.8 (1997-1999) to 44.5 (2012-2014) per 100,000 women. The adjusted rates for the European population also increased from 116.2 (1997-1999) to 136.9 (2012-2014) per 100,000 men, and from 11 (1997-1999) to 24.5 (2012-2014) per 100,000 women. In the south and centre of the province, there were municipalities with high relative hazards, several of them higher than 2 with posterior probabilities of 1. CONCLUSIONS: Tumours associated with tobacco increased in the triennial studied, especially in women. The different geographical distribution can be used as a tool to prevent tobacco consumption in the areas involved.


Assuntos
Neoplasias/epidemiologia , Fumar Tabaco/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Sistema de Registros , Fatores de Risco , Distribuição por Sexo , Espanha/epidemiologia , Fumar Tabaco/efeitos adversos
20.
Int J Oral Maxillofac Surg ; 47(9): 1166-1177, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29459128

RESUMO

The aim of this meta-analysis was to verify the clinical viability of single implant-retained mandibular overdentures (SIMO). An electronic search of the PubMed and Cochrane databases was performed (end date July 2017); this was supplemented by a manual search of the literature. Only prospective clinical trials and randomized controlled trials (RCTs) that evaluated SIMO with a minimum follow-up of 12 months were included. The meta-analysis was based on the Mantel-Haenszel method. Dental implant and prosthetic failure were the dichotomous outcome measures; these were evaluated through the risk ratio (RR) and odds ratio (OR), with corresponding 95% confidence intervals (CI). Of 499 articles identified, nine fulfilled the inclusion criteria. A total of 205 implants were placed in patients with a mean age of 64.1 years; the cumulative survival rate was 96.6% over a mean follow-up period of 37.3 months. The procedure used (SIMO vs. two implant-retained mandibular overdenture) did not affect dental implant failure (P=0.45) or prosthetic failure (P=0.65): RR 1.06 (95% CI 0.91-1.23) and RR 0.88 (95% CI 0.51-1.51), respectively; OR 2.56 (95% CI 0.27-24.39; P=0.41) and OR 0.44 (95% CI 0.15-1.26; P=0.13), respectively. Within the limitations of this systematic review and meta-analysis, SIMO with a complete denture as the opposing arch may be considered an alternative treatment for completely edentulous patients. However, this study also confirmed the need for more RCTs on this topic.


Assuntos
Prótese Dentária Fixada por Implante , Revestimento de Dentadura , Mandíbula , Implantes Dentários para Um Único Dente , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Humanos
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