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91.
92.
MARTIN JUNG MICHEL VERSTRAETE NADINE GOBRON MARKUS REICHSTEIN DARIO PAPALE ALBERTE BONDEAU MONICA ROBUSTELLI BERNARD PINTY 《Global Change Biology》2008,14(10):2349-2364
We present an approach to estimate gross primary production (GPP) using a remotely sensed biophysical vegetation product (fraction of absorbed photosynthetically active radiation, FAPAR) from the European Commission Joint Research Centre (JRC) in conjunction with GPP estimates from eddy covariance measurement towers in Europe. By analysing the relationship between the cumulative growing season FAPAR and annual GPP by vegetation type, we find that the former can be used to accurately predict the latter. The root mean square error of prediction is of the order of 250 gC m−2 yr−1. The cumulative growing season FAPAR integrates over a number of effects relevant for GPP such as the length of the growing season, the vegetation's response to environmental conditions and the amount of light harvested that is available for photosynthesis. We corroborate the proposed GPP estimate (noted FAPAR-based productivity assessment+land cover, FPA+LC) on the continental scale with results from the MOD17+radiation-use efficiency model, an artificial neural network up-scaling approach (ANN) and the Lund–Potsdam–Jena managed Land biosphere model (LPJmL). The closest agreement of the mean spatial GPP pattern among the four models is between FPA+LC and ANN (R2= 0.74). At least some of the discrepancy between FPA-LC and the other models result from biases of meteorological forcing fields for MOD17+, ANN and LPJmL. Our analysis further implies that meteorological information is to a large degree redundant for GPP estimation when using the JRC-FAPAR. A major advantage of the FPA+LC approach presented in this paper lies in its simplicity and that it requires no additional meteorological input driver data that commonly introduce substantial uncertainty. We find that results from different data-oriented models may be robust enough to evaluate process-oriented models regarding the mean spatial pattern of GPP, while there is too little consensus among the diagnostic models for such purpose regarding inter-annual variability. 相似文献
93.
Testosterone Cytosol “Receptor” in the Rat Levator Ani Muscle 总被引:4,自引:0,他引:4
IT is not known whether the “anabolic” action of the androgenic hormone testosterone1, especially on muscular growth and metabolism, can be explained by the presence and the possible metabolism and “receptors” of the hormone in muscles. There are indeed several categories of muscles which, when dependent on androgens, may or may not respond directly to testosterone. It is conceivable that the hormone affects certain muscles through an increased (sexual or general) activity by way of the central nervous system, or because of the release of another hormone, or secondarily through some change of general metabolism. 相似文献
94.
Kyu-Sik CHANG Jin-Sung JUNG Chan PARK Dong-Kyu LEE E-Hyun SHIN 《Entomological Research》2009,39(3):196-200
The susceptibility of members of the Anopheles sinensis Group in Korea to insecticides was evaluated under laboratory conditions using 15 insecticides currently used by local public health centers in Korea. The insecticides included eight pyrethroids, six organophosphates and a pyrazol analogue. Based on their LC50 values, the order of susceptibility of An. sinensis larvae to the insecticides was bifenthrin, chlorfenapyr, α-cypermethrin and λ-cyhalothrin, with values of 0.009, 0.04, 0.06 and 0.08 p.p.m., respectively. The least susceptibility was obtained with fenitrothion, with an LC50 of 7.7 p.p.m. In the comparative resistance test, the resistance ratios (RR) of 14 insecticides were compared to each other using two strains of members of the An. sinensis Group collected in the locality in 2001 and 2008. Anopheles spp. demonstrated higher RR to organophosphates such as fenthion, and low RR for the pyrethroids. Among the organophosphates, fenthion had the highest RR of 33.3 and 270.0 fold differences for LC50 and LC90 values, respectively. Among the pyrethroids, permethrin was observed to have the highest RR of 3.8 and 1.8 fold differences for LC50 and LC90 values, respectively. However, there were no significant differences in susceptibility to chlorfenapyr, chlorpyrifos, deltamethrin and fenitrothion. An. sinensis s. l. was more susceptible to the six insecticides bifenthrin, λ-cyhalothrin, α-cypermethrin, cypermethrin, cyfluthrin and pyridafenthion, showing 0.03, 0.06, 0.3, 0.3, 0.4 and 0.4 fold differences in resistance rates (RR LC50 ), respectively. 相似文献
95.
A new riffle beetle species Optioservus gapyeongensis n. sp. is described from the adult and larval stages. Heterlimnius hasegawai (Nomura), previously misidentified in Korea as Optioservus (Cyclolimnius) kubotai Nomura or Optioservus variabilis Nomura, is redescribed. The adults and larvae of both species inhabit attached mosses on substrates of clean mountain streams, headwaters or springs. Photographs of dorsal adults and habitats and line drawings of diagnostic characters are provided. 相似文献