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Human–Dromedary Camel Interactions and the Risk of Acquiring Zoonotic Middle East Respiratory Syndrome Coronavirus Infection
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C. Gossner N. Danielson A. Gervelmeyer F. Berthe B. Faye K. Kaasik Aaslav C. Adlhoch H. Zeller P. Penttinen D. Coulombier 《Zoonoses and public health》2016,63(1):1-9
Middle East respiratory syndrome coronavirus (MERS‐CoV) cases without documented contact with another human MERS‐CoV case make up 61% (517/853) of all reported cases. These primary cases are of particular interest for understanding the source(s) and route(s) of transmission and for designing long‐term disease control measures. Dromedary camels are the only animal species for which there is convincing evidence that it is a host species for MERS‐CoV and hence a potential source of human infections. However, only a small proportion of the primary cases have reported contact with camels. Other possible sources and vehicles of infection include food‐borne transmission through consumption of unpasteurized camel milk and raw meat, medicinal use of camel urine and zoonotic transmission from other species. There are critical knowledge gaps around this new disease which can only be closed through traditional field epidemiological investigations and studies designed to test hypothesis regarding sources of infection and risk factors for disease. Since the 1960s, there has been a radical change in dromedary camel farming practices in the Arabian Peninsula with an intensification of the production and a concentration of the production around cities. It is possible that the recent intensification of camel herding in the Arabian Peninsula has increased the virus' reproductive number and attack rate in camel herds while the ‘urbanization’ of camel herding increased the frequency of zoonotic ‘spillover’ infections from camels to humans. It is reasonable to assume, although difficult to measure, that the sensitivity of public health surveillance to detect previously unknown diseases is lower in East Africa than in Saudi Arabia and that sporadic human cases may have gone undetected there. 相似文献
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Tapani Hirvonen Joni Orava Niko Penttinen Katri Luostarinen Markku Hauta-Kasari Mika Sorjonen Kai-Erik Peiponen 《Wood Science and Technology》2014,48(5):995-1003
In this study, a comprehensive spectral image database of Nordic sawn timbers for public use was measured. Economically significant Finnish wood species birch (Betula sp.), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) were chosen for inclusion in the database. The total of samples was 107 containing heartwood, sapwood, decayed wood, blue stain, mold, resin, early wood, late wood, knots, cracks, pith, reaction wood and bark. Board and crosscut samples were measured in frozen, melted and room-dried conditions. The reflectance of samples was measured over a 300- to 2,500-nm wavelength range. Additionally, the photoluminescence of samples excited by an ultraviolet B light source was measured. The spot size used was 250 μm with an 80 mm \(\times \) 200 mm imaging area, and produced all in all 44 million spectra. In this paper, examples of the possibilities of this spectral image database as a means of detection of the spatial distribution of aromatic lignin and the moisture content (MC) of nonfrozen timber were introduced and provided. From the results, it was found that it was possible to detect the lignin distribution from spectral images, and simple and robust methods for wood MC estimations were also introduced. 相似文献
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In order to respond to global competition challenges, the wood-processing industry in Finland and elsewhere is outsourcing
roundwood harvesting to harvesting contractors. The industry also seeks to negotiate with fewer, larger and more diverse contractor
enterprises. The weak profitability, liquidity and solvency of harvesting contractors and the consequent difficulty in hiring
qualified machine operators make networking and enterprise growth a complicated process. Financial data of 1,060 Finnish wood
harvesting contractors from the period 2001 to 2007 were studied using the ‘closing of the accounts’ data. The material represents
most of the full-time contractors. For 2007 net profit was about 6%, credit share of turnover over 50% and median financial
reserve €18,000. High machine depreciation and interest expenses together with low solidity make it difficult for small enterprises
to absorb seasonal variations and to cope with recessions. Profitability varies considerably amongst smallest enterprises,
which most often are sole-operator enterprises. Moreover, even the median profit of the smallest enterprises tends to be negative,
which means that enterprise capital will be consumed and many enterprises are at risk of failure. Larger enterprises are more
likely to be limited liability companies. Their median profit is clearly positive and the profit varies relative little between
enterprises. 相似文献
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Importance of dose metrics for lethal and sublethal sediment metal toxicity in the oligochaete worm Lumbriculus variegatus 总被引:2,自引:2,他引:0
Olli-Pekka Penttinen Johanna Kilpi-Koski Maritta Jokela Katri Toivainen Ari Väisänen 《Journal of Soils and Sediments》2008,8(1):59-66
Background, Aims, and Scope There is an increasing demand for controlled toxicity tests to predict biological effects related to sediment metal contamination.
In this context, questions of metal-specific factors, sensitivity of toxicity endpoints, and variability in exposure duration
arise. In addition, the choice of the dose metrics for responses is equally important and is related to the applicability
of the concept of critical body residue (CBR) in exposure assessments, as well as being the main focus of this study.
Methods Experiments were conducted to assess toxicity of Cd, Cr, Cu and Pb to the oligochaete worm Lumbriculus variegatus with the aim of determining CBRs for two response metrics. Mortality and feeding activity of worms exposed to sediment-spiked
metals were used as end-points in connection with residue analyses from both the organisms and the surrounding media.
Results LC50 values were 0.3, 1.4, 5.2, and 6.7 mg/L (from 4.7 μmol/L to 128.0 μmol/L), and the order of toxicity, from most toxic
to least toxic, was Cu > Cd > Pb>Cr. By relating toxicity to body residue, variability in toxicity among the metals decreased
and the order of toxicity was altered. The highest lethal residue value was obtained for Cu (10.8 mmol/kg) and the lowest
was obtained for Cd (2.3 mmol/kg). In the 10-d sublethal test, both time and metal exposure were an important source of variation
in the feeding activity of worms. The significant treatment effects were observed from worms exposed to Cd or Pb, with the
controls yielding the highest feeding rate. However, quantitative changes in the measured endpoint did not correlate with
the exposure concentrations or body residues, which remained an order of magnitude lower than in the acute exposures.
Discussion Both response metrics were able to detect a toxic effect of the metals. However, the ranking of metal toxicity was dependant
on the choice of the dose metric used. An attempt to form a causal mortality-mediated link between tissue residues and metal
toxicity was successful in water-only exposures. The results also indicated that egestion rate was a sensitive toxicity end
point for predicting the effects of sediment contamination.
Conclusions By relating the biological response with the tissue metal residues, toxicity data was comparable to both environmental media
as well as different response metrics and time scales. The results also revealed the importance of metal toxicity ranking
on a molar basis and, furthermore, a direct link to the CBR concept was established.
Recommendations and Perspectives There is a growing demand for methods to assess the effects of contaminated sediments to benthic fauna and whole aquatic ecosystems.
Such information is needed for sediment quality guidelines that are currently being developed in many countries and remediation
processes. The use of body residues as a dose metric in metal toxicity studies may help to overcome difficulties related to
bioavailability issues commonly faced in sediment toxicity studies.
ESS-Submission Editor: Prof. Dr. Henner Hollert (henner.hollert@bio5.rwth-aachen.de) 相似文献
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S. Stark S. Hilli S. Willför A. I. Smeds M. Reunanen M. Penttinen R. Hautajärvi 《European Journal of Soil Science》2012,63(1):65-74
Carbohydrates and lipophilic compounds constitute an important component of litter and soil organic matter in boreal forests, but are still poorly identified. We characterized needle litter and coarse tree litter (cones, seeds, bark and twigs) from coniferous trees (Pinus sylvestris L. and Picea abies Karst.), and moss litter (Pleurozium schreberi, Hylocomnium speldens), fermentation (F) and humus (H) layers in four boreal forest sites in Finland using a combination of sequential fractionation (non‐polar extractions, NPE; water‐soluble extractions, WSE; acid‐soluble fraction, AS) and detailed analyses on the soluble fractions using GC‐MS. Comparisons among the different layers of the soil organic horizon were used to assess which lipophilic compounds and carbohydrates increased in the F and H layers in proportion to their relative abundance in the litter layer and thus might have a large potential to accumulate in soil organic matter. Both concentrations and relative proportions of different compounds varied among the soil layers. Several of the fatty acids (FAs) found in the litter samples were absent in the F and the H layers. Needle and coarse tree litter contained a wide range of di‐ and triterpenes, but in the F and H layers oxidized forms of dehydroabietic acid and sterols were abundant. The large proportion of dehydroabietic acid in the lipophilic fraction in the H layer suggests that it may be poorly degradable by soil microorganisms, probably because of its anti‐microbial function in trees. The composition of the acid‐soluble fraction indicated that the proportion of cellulose in relation to hemicelluloses increased from the litter layer to the F and H layers. Put together, changes in the relative proportions of organic compounds in soluble fractions indicate that selective preservation of compounds, litter input by plant roots and microbial synthesis of compounds all contribute to the accumulation of aliphatic compounds in the H layer of boreal forests. 相似文献
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Markku J. Penttinen 《European Journal of Forest Research》2006,125(4):335-343
This paper analyses timber harvesting in the Finnish economic and wood production environment. Empirical evidence including stumpage prices, silvicultural costs, etc., since 1949 covers all non-industrial private forestry. Stumpage price and volume growth processes are proxied by GBMs. Optimal harvesting age solutions and numerical results recognising price drift, price and growth volatility, volume growth, value growth and stand establishment costs, as well as thinning benefits, are provided for Scots pine. Moreover, comparative static and sensitivity solutions, including numerical results, show the impact of the discount rate, price drift, and price and growth volatilities on optimal harvesting age. Price volatility prolonged harvesting age by some 5–9 years, and growth volatility by about 1–2, but negative price drift for discount rates from 5 to 2% fell by roughly 6–10 years. Ignoring the future thinning benefits prolonged the harvesting age only by 1–2 years, but ignoring future stand establishment costs reduced it by 2–4 years. Including the price drift and volatility violated the 70 year age limit in the Forest Act for discount rates exceeding 3.5%. The recommended harvesting age of 80 years could be established only by ignoring the price drift. In all, this study produces solutions and programs that can be incorporated into a forest management planning software product widely used in Finland (Hynynen et al. in For Ecol Manage 207(1–2):5–18, 2005).
相似文献
Markku J. PenttinenEmail: Phone: +358-10-2112244Fax: +358-10-2112104 |
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Hou Shuzhen Wang Xin Shafi Mohammad Penttinen Petri Xu Weijie Ma Jiawei Zhong Bin Guo Jia Xu Meizhen Ye Zhengqian Liu Dan Wang Hailong 《Journal of Soils and Sediments》2019,19(10):3512-3520
Journal of Soils and Sediments - Intercropping is a promising technique for remediation of soils contaminated with heavy metals. Organic acids can increase the availability of heavy metals in soil.... 相似文献
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