Cretaceous is characterized by high atmospheric CO2 concentration and a resultantly high temperature. Thus, the Earth system, which operated during the greenhouse condition, can be deduced by the investigation of the ...Cretaceous is characterized by high atmospheric CO2 concentration and a resultantly high temperature. Thus, the Earth system, which operated during the greenhouse condition, can be deduced by the investigation of the paleoclimate during the Cretaceous. However, information of paleoclimate from continental inland-basins is scarce compared to that from continental margin marine-basins. In this research, the changes of weathering condition through the whole Cretaceous Period were reconstructed by analyzing the whole-rock chemical composition and clay mineral composition of mudstone samples collected in the Sichuan Basin, SW China. The reconstructed paleoweathering intensity positively correlates with paleotemperature estimate, indicating that Cenomanian-Turonian stages were climatic optimum in the Sichuan Basin as well. Furthermore, the result suggests a Cenomanian-Turonian extremely high amplitude humidity fluctuation.展开更多
Soil carbon dioxide emission: soil respiration is representing a major contributor of accumulating carbon dioxide in the atmosphere that aids to accelerate global warming and altering the climate. Soil temperature, so...Soil carbon dioxide emission: soil respiration is representing a major contributor of accumulating carbon dioxide in the atmosphere that aids to accelerate global warming and altering the climate. Soil temperature, soil water content, sun light and vegetation are considered most common regulators of soil respiration variations in ecosystem. The soil respiration was measured in grassland intended to examine how the soil respiration changed with varying climatic factors, for two years (2015 and 2016) in temperate grassland of Annapurna Conservation Area (ACA), Nepal. In the study, soil temperature accounted exponential function of soil respiration variation at 42.9%, 19.1% and 23.3%, and temperature sensitivity of the soil respiration (Q10) obtained at 6.2, 1.4 and 1.8 in October 2015 and April 2016 and both the measurements were combined, respectively. Significant negative (R2 = 0.50, p < 0.05, October 2015) and positive (R2 = 0.084, p < 0.05, April 2016) exponential function of soil respiration and soil water content were determined, where high soil respiration values were always measured between 30% and 35% of the soil water content. However, linear significant relationship was determined (R2 = 0.376, p < 0.05) between soil respiration and photosynthetic photon flux density (PPFD). Soil respiration value averaged in October 2015 was 357 mg CO2 m-2 h-1 and in April 2016 it was 444.6 mg CO2 m-2 h-1. Above- and below-ground plant biomasses were obtained at 231.1 g d w m-2 and 1538.8 g d w m-2 in October, and at 449.9 g d w m-2 and 349.0 g d w m-2 in April, respectively. This study showed variation of soil respiration in relation to the factors such as soil temperature, soil water content and photosynthetic photon flux density signifying their importance in governing ecosystem function and carbon balance of the temperate grassland ecosystem.展开更多
Dear Editor,MPL is a cytokine receptor that regulates the production of myeloid cells,in particular megakaryocytes and platelets(Kaushansky,2005).Dimerization of MPL is important not only for the initiation of signall...Dear Editor,MPL is a cytokine receptor that regulates the production of myeloid cells,in particular megakaryocytes and platelets(Kaushansky,2005).Dimerization of MPL is important not only for the initiation of signalling(Kaushansky,2005)but also for the resistance to a recent therapy for myeloproliferative neoplasms(Koppikar et al.,2012).In the current model,cytokine receptors exist as a mixture of monomers and dimers without ligand stimulation,while ligand binding induces additional receptor dimerization(Kaushansky,2005).展开更多
文摘Cretaceous is characterized by high atmospheric CO2 concentration and a resultantly high temperature. Thus, the Earth system, which operated during the greenhouse condition, can be deduced by the investigation of the paleoclimate during the Cretaceous. However, information of paleoclimate from continental inland-basins is scarce compared to that from continental margin marine-basins. In this research, the changes of weathering condition through the whole Cretaceous Period were reconstructed by analyzing the whole-rock chemical composition and clay mineral composition of mudstone samples collected in the Sichuan Basin, SW China. The reconstructed paleoweathering intensity positively correlates with paleotemperature estimate, indicating that Cenomanian-Turonian stages were climatic optimum in the Sichuan Basin as well. Furthermore, the result suggests a Cenomanian-Turonian extremely high amplitude humidity fluctuation.
文摘Soil carbon dioxide emission: soil respiration is representing a major contributor of accumulating carbon dioxide in the atmosphere that aids to accelerate global warming and altering the climate. Soil temperature, soil water content, sun light and vegetation are considered most common regulators of soil respiration variations in ecosystem. The soil respiration was measured in grassland intended to examine how the soil respiration changed with varying climatic factors, for two years (2015 and 2016) in temperate grassland of Annapurna Conservation Area (ACA), Nepal. In the study, soil temperature accounted exponential function of soil respiration variation at 42.9%, 19.1% and 23.3%, and temperature sensitivity of the soil respiration (Q10) obtained at 6.2, 1.4 and 1.8 in October 2015 and April 2016 and both the measurements were combined, respectively. Significant negative (R2 = 0.50, p < 0.05, October 2015) and positive (R2 = 0.084, p < 0.05, April 2016) exponential function of soil respiration and soil water content were determined, where high soil respiration values were always measured between 30% and 35% of the soil water content. However, linear significant relationship was determined (R2 = 0.376, p < 0.05) between soil respiration and photosynthetic photon flux density (PPFD). Soil respiration value averaged in October 2015 was 357 mg CO2 m-2 h-1 and in April 2016 it was 444.6 mg CO2 m-2 h-1. Above- and below-ground plant biomasses were obtained at 231.1 g d w m-2 and 1538.8 g d w m-2 in October, and at 449.9 g d w m-2 and 349.0 g d w m-2 in April, respectively. This study showed variation of soil respiration in relation to the factors such as soil temperature, soil water content and photosynthetic photon flux density signifying their importance in governing ecosystem function and carbon balance of the temperate grassland ecosystem.
基金supported by the Ministry of Education,Culture,Sports,Science and Technology(KAKENHI 24121712 to Y.S.,21121004,15H04358,and 15H01527 to T.F.,and the Program to Disseminate Tenure Tracking System to K.S.).
文摘Dear Editor,MPL is a cytokine receptor that regulates the production of myeloid cells,in particular megakaryocytes and platelets(Kaushansky,2005).Dimerization of MPL is important not only for the initiation of signalling(Kaushansky,2005)but also for the resistance to a recent therapy for myeloproliferative neoplasms(Koppikar et al.,2012).In the current model,cytokine receptors exist as a mixture of monomers and dimers without ligand stimulation,while ligand binding induces additional receptor dimerization(Kaushansky,2005).
