SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(de Macedo A. R. L.) "

Sökning: WFRF:(de Macedo A. R. L.)

  • Resultat 1-12 av 12
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Barausse, Enrico, et al. (författare)
  • Prospects for fundamental physics with LISA
  • 2020
  • Ingår i: General Relativity and Gravitation. - : SPRINGER/PLENUM PUBLISHERS. - 0001-7701 .- 1572-9532. ; 52:8
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • In this paper, which is of programmatic rather than quantitative nature, we aim to further delineate and sharpen the future potential of the LISA mission in the area of fundamental physics. Given the very broad range of topics that might be relevant to LISA,we present here a sample of what we view as particularly promising fundamental physics directions. We organize these directions through a "science-first" approach that allows us to classify how LISA data can inform theoretical physics in a variety of areas. For each of these theoretical physics classes, we identify the sources that are currently expected to provide the principal contribution to our knowledge, and the areas that need further development. The classification presented here should not be thought of as cast in stone, but rather as a fluid framework that is amenable to change with the flow of new insights in theoretical physics.
  •  
2.
  •  
3.
  •  
4.
  •  
5.
  •  
6.
  •  
7.
  •  
8.
  • Razavi-Shearer, Devin M., et al. (författare)
  • Adjusted estimate of the prevalence of hepatitis delta virus in 25 countries and territories
  • 2024
  • Ingår i: JOURNAL OF HEPATOLOGY. - 0168-8278 .- 1600-0641. ; 80:2, s. 232-242
  • Tidskriftsartikel (refereegranskat)abstract
    • Background & Aims: Hepatitis delta virus (HDV) is a satellite RNA virus that requires the hepatitis B virus (HBV) for assembly and propagation. Individuals infected with HDV progress to advanced liver disease faster than HBV-monoinfected individuals. Recent studies have estimated the global prevalence of anti-HDV antibodies among the HBV-infected population to be 5-15%. This study aimed to better understand HDV prevalence at the population level in 25 countries/territories. Methods: We conducted a literature review to determine the prevalence of anti-HDV and HDV RNA in hepatitis B surface antigen (HBsAg)-positive individuals in 25 countries/territories. Virtual meetings were held with experts from each setting to discuss the findings and collect unpublished data. Data were weighted for patient segments and regional heterogeneity to estimate the prevalence in the HBV-infected population. The findings were then combined with The Polaris Observatory HBV data to estimate the anti-HDV and HDV RNA prevalence in each country/territory at the population level. Results: After adjusting for geographical distribution, disease stage and special populations, the anti-HDV prevalence among the HBsAg+ population changed from the literature estimate in 19 countries. The highest anti-HDV prevalence was 60.1% in Mongolia. Once adjusted for the size of the HBsAg+ population and HDV RNA positivity rate, China had the highest absolute number of HDV RNA+ cases. Conclusions: We found substantially lower HDV prevalence than previously reported, as prior meta-analyses primarily focused on studies conducted in groups/regions that have a higher probability of HBV infection: tertiary care centers, specific risk groups or geographical regions. There is large uncertainty in HDV prevalence estimates. The implementation of reflex testing would improve estimates, while also allowing earlier linkage to care for HDV RNA+ individuals. The logistical and economic burden of reflex testing on the health system would be limited, as only HBsAg+ cases would be screened.
  •  
9.
  • Gurgel-Giannetti, J., et al. (författare)
  • A novel complex neurological phenotype due to a homozygous mutation in FDX2
  • 2018
  • Ingår i: Brain. - : Oxford University Press (OUP). - 0006-8950 .- 1460-2156. ; 141, s. 2289-2298
  • Tidskriftsartikel (refereegranskat)abstract
    • Defects in iron-sulphur [Fe-S] cluster biogenesis are increasingly recognized as causing neurological disease. Mutations in a number of genes that encode proteins involved in mitochondrial [Fe-S] protein assembly lead to complex neurological phenotypes. One class of proteins essential in the early cluster assembly are ferredoxins. FDX2 is ubiquitously expressed and is essential in the de novo formation of [2Fe-2S] clusters in humans. We describe and genetically define a novel complex neurological syndrome identified in two Brazilian families, with a novel homozygous mutation in FDX2. Patients were clinically evaluated, underwent MRI, nerve conduction studies, EMG and muscle biopsy. To define the genetic aetiology, a combination of homozygosity mapping and whole exome sequencing was performed. We identified six patients from two apparently unrelated families with autosomal recessive inheritance of a complex neurological phenotype involving optic atrophy and nystagmus developing by age 3, followed by myopathy and recurrent episodes of cramps, myalgia and muscle weakness in the first or second decade of life. Sensory-motor axonal neuropathy led to progressive distal weakness. MRI disclosed a reversible or partially reversible leukoencephalopathy. Muscle biopsy demonstrated an unusual pattern of regional succinate dehydrogenase and cytochrome c oxidase deficiency with iron accumulation. The phenotype was mapped in both families to the same homozygous missense mutation in FDX2 (c. 431C > T, p. P144L). The deleterious effect of the mutation was validated by real-time reverse transcription polymerase chain reaction and western blot analysis, which demonstrated normal expression of FDX2 mRNA but severely reduced expression of FDX2 protein in muscle tissue. This study describes a novel complex neurological phenotype with unusual MRI and muscle biopsy features, conclusively mapped to a mutation in FDX2, which encodes a ubiquitously expressed mitochondrial ferredoxin essential for early [Fe-S] cluster biogenesis.
  •  
10.
  • Mendieta-Leiva, Glenda, et al. (författare)
  • EpIG-DB: A database of vascular epiphyte assemblages in the Neotropics
  • 2020
  • Ingår i: Journal of Vegetation Science. - : Wiley. - 1100-9233 .- 1654-1103. ; 31, s. 518-528
  • Tidskriftsartikel (refereegranskat)abstract
    • Vascular epiphytes are a diverse and conspicuous component of biodiversity in tropical and subtropical forests. Yet, the patterns and drivers of epiphyte assemblages are poorly studied in comparison with soil-rooted plants. Current knowledge about diversity patterns of epiphytes mainly stems from local studies or floristic inventories, but this information has not yet been integrated to allow a better understanding of large-scale distribution patterns. EpIG-DB, the first database on epiphyte assemblages at the continental scale, resulted from an exhaustive compilation of published and unpublished inventory data from the Neotropics. The current version of EpIG-DB consists of 463,196 individual epiphytes from 3,005 species, which were collected from a total of 18,148 relevés (host trees and ‘understory’ plots). EpIG-DB reports the occurrence of ‘true’ epiphytes, hemiepiphytes and nomadic vines, including information on their cover, abundance, frequency and biomass. Most records (97%) correspond to sampled host trees, 76% of them aggregated in forest plots. The data is stored in a TURBOVEG database using the most up-to-date checklist of vascular epiphytes. A total of 18 additional fields were created for the standardization of associated data commonly used in epiphyte ecology (e.g. by considering different sampling methods). EpIG-DB currently covers six major biomes across the whole latitudinal range of epiphytes in the Neotropics but welcomes data globally. This novel database provides, for the first time, unique biodiversity data on epiphytes for the Neotropics and unified guidelines for future collection of epiphyte data. EpIG-DB will allow exploration of new ways to study the community ecology and biogeography of vascular epiphytes.
  •  
11.
  • Nobrega, M. S., et al. (författare)
  • Mangrove microbiome reveals importance of sulfur metabolism in tropical coastal waters
  • 2022
  • Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 813
  • Tidskriftsartikel (refereegranskat)abstract
    • Mangroves under macro-tidal regimes are global carbon sequestration hotspots but the microbial drivers of biogeochemical cycles remain poorly understood. Here, we investigate the drivers of mangrove microbial community composition across a porewater-creek-estuary-ocean continuum. Observations were performed on the Amazon region in one of the largest mangrove systems worldwide with effective sequestration of organic carbon buried in soils and dissolved carbon via outwelling to the ocean. The potential export to the adjacent oceanic region ranged from 57 to 380 kg of dissolved and particulate organic carbon per second (up to 33 thousand tons C per day). Macro tides modulated microbial communities and their metabolic processes, e.g., anoxygenic phototrophy, sulfur, and nitrogen cycling. Respiration, sulfur metabolism and dissolved organic carbon (DOC) levels were linked to functional groups and microbial cell counts. Total microbial counts decreased and cyanobacteria counts peaked in the spring tide. The microbial groups driving carbon, nitrogen, sulfur and methane cycles were consistent across all spatial scales. Taxonomic groups engaged in sulfur cycling (Allochromatium, Desulfovibrio, and Thibacillus) within mangroves were abundant at all scales. Tidally-driven porewater exchange within mangroves drove a progressive increase of sulfur cycle taxonomic groups and their functional genes both temporally (tidal cycles) and spatially (from mangrove porewater to continental shelf). Overall, we revealed a unified and consistent response of microbiomes at different spatial and temporal scales to tidally-driven mangrove porewater exchange.
  •  
12.
  • Han, T., et al. (författare)
  • Emerging Drone Trends for Blockchain-Based 5G Networks: Open Issues and Future Perspectives
  • 2021
  • Ingår i: Ieee Network. - : Institute of Electrical and Electronics Engineers (IEEE). - 0890-8044 .- 1558-156X. ; 35:1, s. 38-43
  • Tidskriftsartikel (refereegranskat)abstract
    • Unmanned aerial vehicles, commonly known as drones, are receiving growing research interest due to their ability to carry a multitude of sensors and to connect to mobile networks. They are also able to move freely across the air, which enables the creation of numerous applications that were until now considered impracticable. However, such applications may require high computational resources, reliable connection, and high data transmission rates to accomplish different tasks. Therefore, in this work, first, we discuss 5G communication networks and mobile edge computing (MEC) as promising technologies that can provide several benefits to drone-enabled environments and solve some of the presented issues. We also comment on 5G and MEC approaches, presenting the state of the art and seeking to solve each of the latter issues presented. Afterward, we introduce new security concerns of drone communication networks, given their recent popularity. These concerns are related to the possibility of malicious users taking advantage of this brand new technology, which has made many governments ban drones due to public safety. Next, blockchain technology is brought in as a novel solution to the security issues due to its decentralized nature, making it inherently safe. This article also surveys contributions that make use of each of the technologies mentioned to improve the emerging drone industry. Subsequently, we discuss open issues and future perspectives.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-12 av 12

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy