421 research outputs found
Prevalence of Opisthorchis viverrini-like fluke infection in ducks in Binh Dinh Province, Central Vietnam
Following the first report of Opisthorchis viverrini infection in a domestic duck in Phu My District of Binh Dinh Province, Central Vietnam, many other cases were observed in the province. We determined the infection rate and intensity of O. viverrini infection in ducks in 4 districts of the province. A total of 178 ducks were randomly selected from 34 farms for examination of flukes in the liver and gall bladder. An infection rate of 34.3% (range 20.7-40.4% among districts) was found; the intensity of infection was 13.8 worms per infected duck (range 1-100). These findings show the role of ducks as a host for O. viverrini, duck genotype, which is sympatric with the human O. viverrini genotype in this province. It also stresses the need for investigations on the zoonotic potential and the life cycle of this parasite
Sero-epidemiological status and risk factors of toxoplasmosis in pregnant women in Northern Vietnam
Background: In Vietnam, few studies have determined the epidemiological status of toxoplasmosis in pregnant women and no routine prenatal screening is in place. This study was conducted to evaluate the seroprevalence of this zoonotic parasitic infection in pregnant women in Northern Vietnam and to assess the association with awareness, risk factors and congenital toxoplasmosis.
Methods: Approximately 800 pregnant women were included in the study from two hospitals, one in Hanoi and one in Thai Binh province, which is known to have a dense cat population. Serological immunoglobulin G (IgG) and immunoglobulin M (IgM) detection was performed to estimate the seroprevalence of toxoplasmosis and sero-incidence of maternal and congenital toxoplasmosis. In addition, a survey was conducted about awareness, clinical history, presentation of signs and symptoms relating to toxoplasmosis and to detect biologically plausible and socio-demographic risk factors associated with toxoplasmosis. Associations with seroprevalence were assessed using univariable and multivariable analysis.
Results: The mean IgG seroprevalence after the full diagnostic process was 4.5% (95% confidence interval(CI): 2.7–7.0) and 5.8% (95% CI: 3.7–8.6) in Hanoi and Thai Binh hospital, respectively, and included one seroconversion diagnosed in Thai Binh hospital. Only 2.0% of the pregnant women in Hanoi hospital and 3.3% in Thai Binh hospital had heard about toxoplasmosis before this study.
Conclusion: Since the percentage of seronegative, and thus susceptible, pregnant women was high and the awareness was low, we suggest to distribute information about toxoplasmosis and its prevention among women of child bearing age. Furthermore, future studies are recommended to investigate why such a low seroprevalence was seen in pregnant women in Northern Vietnam compared to other countries in South East Asia and globally
Neurologic Symptoms in Licensed Private Pesticide Applicators in the Agricultural Health Study
Exposure to high levels of many pesticides has both acute and long-term neurologic consequences, but little is known about the neurotoxicity of chronic exposure to moderate levels of pesticides. We analyzed cross-sectional data from 18,782 white male licensed private pesticide applicators enrolled in the Agricultural Health Study in 1993–1997. Applicators provided information on lifetime pesticide use and 23 neurologic symptoms typically associated with pesticide intoxication. An indicator of more symptoms (≥10 vs. < 10) during the year before enrollment was associated with cumulative lifetime days of insecticide use: odds ratios (95% confidence intervals) were 1.64 (1.36–1.97) for 1–50 days, 1.89 (1.58–2.25) for 51–500 days, and 2.50 (2.00–3.13) for > 500 days, compared with never users. A modest association for fumigants [> 50 days, 1.50 (1.24–1.81)] and weaker relationships for herbicides [> 500 days, 1.32 (0.99–1.75)] and fungicides [> 50 days, 1.23 (1.00–1.50)] were observed. Pesticide use within the year before enrollment was not associated with symptom count. Only associations with insecticides and fumigants persisted when all four pesticide groups were examined simultaneously. Among chemical classes of insecticides, associations were strongest for organophosphates and organochlorines. Associations with cumulative exposure persisted after excluding individuals who had a history of pesticide poisoning or had experienced an event involving high personal pesticide exposure. These results suggest that self-reported neurologic symptoms are associated with cumulative exposure to moderate levels of fumigants and organophosphate and organochlorine insecticides, regardless of recent exposure or history of poisoning
Emulation of a chemical transport model to assess air quality under future emission scenarios for the southwest of Western Australia
Simulation outputs from chemical transport models (CTMs) are essential to plan effective air quality policies. A key strength of these models is their ability to separate out source-specific components which facilitate the simulation of the potential impact of policy on future air quality. However, configuring and running these models is complex and computationally intensive, making the evaluation of multiple scenarios less accessible to many researchers and policy experts. The aim of this work is to present how Gaussian process emulation can provide a top-down approach to interrogating and interpreting the outputs from CTMs at minimal computational cost. A case study is presented (based on fine particle sources in the southwest of Western Australia) to illustrate how an emulator can be constructed to simultaneously evaluate changes in emissions from on-road transport and electricity sectors. This study demonstrates how emulation provides a flexible way of exploring local impacts of electric vehicles and wider regional effects of emissions from electricity generation. The potential for emulators to be applied to other settings involving air quality research is discussed
Modelling storm hydrodynamics on gravel beaches with XBeach-G
The research in this study was funded by the Engineering and Physical Sciences Research Council (EPSRC; EP/H040056/1). The full text is under embargo until 01.09.1
Expansão da agricultura orgânica e os desafios enfrentados por produtores brasileiros na produção e exportação de orgânicos
A agricultura orgânica baseia-se no uso de métodos de cultivos ecológicos, alternativos à agricultura convencional, com o intuito de preservar o meio ambiente. A expansão do mercado mundial de produtos orgânicos decorreu da preocupação com a degradação ambiental e com a segurança do alimento. Entretanto, os produtores orgânicos brasileiros enfrentam desafios tanto no processo produtivo quanto para acessarem o mercado internacional orgânico. Neste contexto, o objetivo deste estudo foi analisar a evolução da produção orgânica e os desafios para produção e exportação dos produtos orgânicos brasileiros, particularmente para o mercado europeu. Para analisar a evolução da produção orgânica foram coletados dados do Instituto Brasileiro de Geografia e Estatística (IBGE), Ministério da Agricultura, Pecuária e Abastecimento (MAPA) e Research Institute of Organic Agriculture (FiBL) sobre a área agropecuária, número de estabelecimentos e de produtores, vendas no varejo, consumo per capita e exportações. Os dados disponíveis mostraram o crescimento contínuo da produção orgânica mundial entre 2000 e 2018. A análise do comércio mundial de orgânicos foi realizada por meio do Modelo Gravitacional. A equação gravitacional estimada utilizou como variável dependente as exportações mundiais de orgânicos. Já as variáveis independentes foram: o Produto Interno Bruto (PIB) e a população dos países exportadores de orgânicos, o PIB e a população da América do Norte e União Europeia, além da área agrícola destinada à produção orgânica tanto dos países exportadores quanto da América do Norte e União Europeia. De acordo com o resultado do modelo, as variáveis determinantes das exportações de orgânicos foram o PIB dos países exportadores, bem como o PIB, a população e a área agrícola orgânica da América do Norte e da União Europeia. Além disso, também foram realizadas entrevistas com agricultores familiares orgânicos brasileiros a fim de investigar os desafios que estes produtores tem encontrado na produção e comercialização de orgânicos. Eles responderam questões relacionadas à produção de orgânicos, aos desafios enfrentados, à importância das políticas públicas para o setor, à certificação e ao acesso ao mercado europeu. Em relação às dificuldades na produção, mencionaram fatores como alto custo e burocracia da certificação, falta de pagamento diferenciado pelo produto orgânico e indisponibilidade de insumos orgânicos. Já em relação aos desafios para exportação para o mercado orgânico europeu, relataram problemas como a falta de conhecimento do processo de exportação, dificuldade na obtenção da certificação orgânica europeia, falta de conhecimento da legislação orgânica europeia e do mercado europeu, bem como a escala de produção para exportação. Os produtores entrevistados consideram as políticas públicas importantes para o desenvolvimento da agricultura orgânica no Brasil, mas que necessitam ser aprimoradas para atender as necessidades dos produtores familiares orgânicos
Increased risk of pneumonia in residents living near poultry farms: does the upper respiratory tract microbiota play a role?
BACKGROUND: Air pollution has been shown to increase the susceptibility to community-acquired pneumonia (CAP). Previously, we observed an increased incidence of CAP in adults living within 1 km from poultry farms, potentially related to particulate matter and endotoxin emissions. We aim to confirm the increased risk of CAP near poultry farms by refined spatial analyses, and we hypothesize that the oropharyngeal microbiota composition in CAP patients may be associated with residential proximity to poultry farms. METHODS: A spatial kernel model was used to analyze the association between proximity to poultry farms and CAP diagnosis, obtained from electronic medical records of 92,548 GP patients. The oropharyngeal microbiota composition was determined in 126 hospitalized CAP patients using 16S-rRNA-based sequencing, and analyzed in relation to residential proximity to poultry farms. RESULTS: Kernel analysis confirmed a significantly increased risk of CAP when living near poultry farms, suggesting an excess risk up to 1.15 km, followed by a sharp decline. Overall, the oropharyngeal microbiota composition differed borderline significantly between patients living <1 km and ≥1 km from poultry farms (PERMANOVA p = 0.075). Results suggested a higher abundance of Streptococcus pneumoniae (mean relative abundance 34.9% vs. 22.5%, p = 0.058) in patients living near poultry farms, which was verified by unsupervised clustering analysis, showing overrepresentation of a S. pneumoniae cluster near poultry farms (p = 0.049). CONCLUSION: Living near poultry farms is associated with an 11% increased risk of CAP, possibly resulting from changes in the upper respiratory tract microbiota composition in susceptible individuals. The abundance of S. pneumoniae near farms needs to be replicated in larger, independent studies
Comparing the sensitivity of chlorophytes, cyanobacteria and diatoms to major-use antibiotics
The occurrence of antibiotic residues in the aquatic environment is an emerging concern. In contrast to daphnia and fish, algae are known to be particularly sensitive to antibiotic exposure. However, to date, a systematic evaluation of the sensitivity of different algal species to antibiotics has not been performed. The aim of the present study was therefore to explore the sensitivity of a battery of algal species towards antibiotic exposures. The present study investigated the growth inhibition effects of three major-use antibiotics, tylosin, lincomycin and trimethoprim, on seven algal species from the chlorophyte, cyanobacteria and diatom groups. Based on EC50 values, cyanobacteria (EC50 = 0.095-0.13 µmol/L) were found to be the most sensitive group to lincomycin followed by chlorophytes (EC50 = 7.36-225.73 µmol/L) and diatoms (EC50 >225.73 µmol/L). Cyanobacteria were also the most sensitive group to tylosin (EC50 = 0.09-0.092 µmol/L) but, for this compound, diatoms (EC50 = 1.33-5.7 µmol/L) were more sensitive than chlorophytes (EC50 = 4.14-81.2 µmol/L). Diatoms were most sensitive to trimethoprim (EC50 = 7.36-74.61 µmol/L) followed by cyanobacteria (EC50 = 315.78-344.45 µmol/L) and chlorophytes (EC50 >344.45 µmol/L) for trimethoprim. While the results of our study partly support the current approach to regulatory environmental risk assessment where cyanobacterial species are recommended for use on antibiotic compounds, they indicate that for some antibiotics this group might not be the most appropriate test organism. We would therefore advocate that environmental risk assessments consider data on three algal groups (chlorophytes, cyanobacteria and diatoms) and use test species from these groups that are consistently found to be the most sensitive (Pseudokirchneriella subcapitata, Anabaena flos-aquae and Navicula pelliculosa). This article is protected by copyright. All rights reserved
One-loop corrections to a scalar field during inflation
The leading quantum correction to the power spectrum of a
gravitationally-coupled light scalar field is calculated, assuming that it is
generated during a phase of single-field, slow-roll inflation.Comment: 33 pages, uses feynmp.sty and ioplatex journal style. v2: matches
version published in JCAP. v3: corrects sign error in Eq. (58). Corrects
final coefficient of the logarithm in Eq. (105). Small corrections to
discussion of divergences in 1-point function. Minor improvements to
discussion of UV behaviour in Sec. 4.
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