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211.
Toona ciliata Roem. (Australian red cedar) requires a nurse-tree overstory to prevent damage from drought and irradiation in some regions of north-eastern Argentina. T. ciliata was planted in the understory of Pinus taeda L. (625 stems/ha), Pinus elliottii Engelm. × Pinus caribaea Morelet (625 stems/ha), and Grevillea robusta A. Cunn. (833 stems/ha) nurse trees, which were thinned to 0, 25, 50, 75 and 100% of the initial densities. We measured initial T. ciliata mortality and growth as well as Leaf Area Index (LAI) based on light transmission. T. ciliata soil water availability and its effect on early growth and mortality were examined by modelling drought stress using the two-dimensional forest hydrology model ForWaDy. Simulated patterns in T. ciliata water stress for the different overstory treatments were consistent with observed patterns of mortality. Early mortality was lowest with a G. robusta overstory, with corresponding lowest drought stress values and high modelled soil water contents in the top soil layer in intermediate and high overstory densities. Mortality was highest with a P. elliottii × P. caribaea overstory in treatments with the highest modelled drought stress values in the most open treatments. The model supported our field observations by indicating that water stress was an important limitation to T. ciliata survival and growth on our study sites. The linkage between T. ciliata establishment success, early growth and soil water availability as indicated by ForWaDy, leads us to conclude that the model is a suitable stand management tool for guiding establishment of T. ciliata plantations. 相似文献
212.
It is well recognized that for the producing companies hedging the commodity price using financial products like forwards or futures has become an important part of the company's production process. But apart from the direct impacts of hedging on the production and hedging costs the use of financial products affects the financing of the company: hedging the volatile commodity prices leads to a reduction of the risk premium the company has to pay for its debt capital, since hedging contributes to more confidence of the investors in the redemption of the debt. In this paper we therefore analyze this dependency of hedging and financing and derive optimal hedging extents for companies in different market situations based on a long-term model. By hedging the commodity price, companies can realize a surplus in profits. Thereby, the optimal hedging extent for a monopolist is often up to 100%, whereas for companies in a polypolistic market the optimum is always less than 100%. These results are illustrated by examples for a producing company. 相似文献
213.
Julia Wynn Jennifer Hoskovec Rebecca D. Carter Meredith J. Ross Sriram C. Perni 《黑龙江环境通报》2023,43(10):1344-1354
Objective
Carrier screening with reflex to single-gene noninvasive prenatal testing (sgNIPT) is an alternative approach for identifying pregnancies at risk for inherited autosomal recessive conditions without the need for a sample from the reproductive partner. This study is the largest clinical validation of this approach in a general population setting.Methods
The clinical performance of carrier screening with reflex to sgNIPT for cystic fibrosis, spinal muscular atrophy, alpha thalassemias, and beta hemoglobinopathies was assessed by collecting pregnancy outcome data on patients who underwent this testing and comparing the neonatal outcome to the assay-predicted fetal risk.Results
Of 42,067 pregnant individuals who underwent screening, 7538 carriers (17.9%) had reflex sgNIPT, and neonatal or fetal outcomes were obtained for 528 cases, including 25 affected pregnancies. Outcomes demonstrated high concordance with sgNIPT, for example, all pregnancies with 9 in 10 personalized fetal risk results were affected (positive predictive value (PPV) of 100% for the sub-group) and the sgNIPT assay showed a sensitivity of 96.0% (95% CI: 79.65%–99.90%), specificity of 95.2% (95% CI: 92.98%–96.92%), average PPV of 50.0% (95% CI: 35.23%–64.77%), and negative predictive value (NPV) of 99.8% (95% CI: 98.84%–99.99%). The end-to-end performance of carrier screening with reflex to sgNIPT was calculated to have a sensitivity of 92.4% and specificity of 99.9%, which are unaffected by partner carrier screening or misattributed paternity unlike a traditional carrier screening workflow, which has a 35% sensitivity and a maximum of 25% PPV (1 in 4) in a real-life setting.Conclusion
This study builds upon earlier findings to confirm that carrier testing with reflex to sgNIPT is highly accurate for general population screening. Given this high accuracy and an NPV of 99.8%, this workflow should be considered as an option for most of the general pregnant population. When the biological partner sample is unavailable, this workflow should be recommended as the first-line approach. 相似文献214.
In animals, mate-choice is often based on sexual signals that carry information and help the receiver make the best choice to improve the receiver’s fitness. Orange visual sexual signals have been hypothesised to carry immune information because they are often due to carotenoid pigments which are also involved in immunity response. Although many studies have focused on the direct relationships between coloration and immunocompetence, few studies have simultaneously studied immunocompetent response and coloration variation after an immune challenge. We tested this hypothesis on starved and ad libitum-fed males of the European tree frog Hyla arborea. Our results show that male coloration is not a reliable indicator of its immune response capacity in this species. However, after an immune challenge induced by a PHA (Phaseolus vulgaris phytohaemagglutinin) injection, starved males presented a significant coloration loss and this alteration was related to the immune response intensity. Taken together, these results suggest that the brighter (lighter) coloration may be used as a cue by female to exclude males with a recent immune challenge, due to diseases or parasites for example. 相似文献
215.
Kariyawasam Thiloka Prenzler Paul D. Howitt Julia A. Doran Gregory S. 《Environmental Chemistry Letters》2022,20(5):2757-2764
Environmental Chemistry Letters - Polycyclic aromatic hydrocarbons are toxic pollutants which persist in the environment. Extraction of polycyclic aromatic hydrocarbons requires large volumes of... 相似文献
216.
Neves Vinicius Machado Heidrich Graciela Marini da Costa Camila Cavalheiro Farias Julia Gomes Nicoloso Fernando Teixeira Pozebon Dirce Dressler Valderi Luiz 《Environmental science and pollution research international》2022,29(40):60084-60097
Environmental Science and Pollution Research - Nanoparticles (NPs) have been progressively applied in the last decades, which may impact the environment. Synthesis of pigments, growing, and... 相似文献
217.
Honscha Laiz Coutelle Penteado Julia Oliveira de Sá Gama Valério da Silva Bonifácio Alícia Aikawa Priscila dos Santos Marina Baisch Paulo Roberto Martins Muccillo-Baisch Ana Luíza da Silva Júnior Flavio Manoel Rodrigues 《Environmental science and pollution research international》2022,29(10):14176-14184
Environmental Science and Pollution Research - Coal exploration and burning activities are among the activities with the greatest potential to cause atmospheric pollution due to the combustion... 相似文献
218.
Julia Roll Randall J. Mitchell Robert J. Cabin & Diane L. Marshall 《Conservation biology》1997,11(3):738-746
We investigated the effects of plant density on reproduction for an insect-pollinated desert mustard (Lesquerella fendleri [Brassicaceae]). Individual reproductive success, as measured by seeds per fruit, proportion of flowers setting fruit, and total seed production, increased with the density of conspecifics within 1 m. However, including the density of conspecifics at greater distances (1–3 m) did not significantly increase the amount of variation in reproductive success explained by the regression model. This implies that processes occurring on a scale of 1 m or less have important effects on reproduction. Total seed production also was greater for high-density plants than for otherwise similar plants with a low-density of conspecifics. We argue that increased pollinator visitation is the most likely cause of this facilitation and that investigations of the effects of rarity on reproductive success should directly consider density along with more commonly used attributes such as population size and fragmentation. 相似文献
219.
Anne Pinton Julia Boubnova François Becmeur Pierre Kuhn Marie-Victoire Senat Julien Stirnemann Marianne Capelle Jonathan Rosenblatt Jérôme Massardier Pascal Vaast Gwenaelle Le Bouar Amélie Desrumaux Laure Connant Laetitia Begue Benoit Parmentier Franck Perrotin Alain Diguet Guillaume Benoist Charles Muszynski Aurélien Scalabre Norbert Winer Jean-Luc Michel Florence Casagrandre-Magne Jean-Marie Jouannic Denis Gallot Perrine Coste Mazeau Emmanuel Sapin Alexis Maatouk Anne-Hélène Saliou Loïc Sentilhes Florence Biquard Nicolas Mottet Romain Favre Alexandra Benachi Nicolas Sananès 《黑龙江环境通报》2020,40(8):949-957
220.