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61.
Andreas Schulte 《植物养料与土壤学杂志》1995,158(5):465-467
Influence of Soil Sample Preparation on Cd and Cu Adsorption in Acid Forest Soils The influence of soil sample preparation on Cd and Cu adsorption was investigated using six acid forest soil samples and comparing adsorption isotherms for fresh and air-dried samples. While no influence of sample preparation on Cd adsorption capacity was found, air-drying resulted in a significant decrease in Cu adsorption density in all six soil samples under investigation at ecotoxicologically relevant concentrations in the soil solution. 相似文献
62.
Yoshie-Stark Y Bez J Wada Y Wäsche A 《Journal of agricultural and food chemistry》2004,52(25):7681-7689
To utilize lupin seeds for food and pharmaceutical applications, lupin seeds were pretreated to remove oil using hexane or carbon dioxide. Two types of lupin protein isolate were prepared. Both types of protein isolate showed good foaming activity, comparable to egg white. Protein isolate extracted under acid conditions showed higher foaming activity than protein isolate extracted at neutral pH. The lipoxygenase activity was much reduced in both of the protein isolates. The protein isolate extracted at neutral pH showed a stronger angiotensin converting enzyme inhibition than the protein isolate extracted under acidic pH. In contrast, the protein isolate extracted under acid conditions had a greater sodium cholate binding capacity, comparable to that of cholestyramine. Lupin samples showed less DPPH radical scavenging activity than deoiled soybean. The deoiling method did not affect the functional properties, lipoxygenase activity, angiotensin converting enzyme inhibition, sodium cholate binding, and radical scavenging activity. 相似文献
63.
Functional shift hypothesis and the relationship between temperature and soil carbon accumulation 总被引:1,自引:0,他引:1
Panagiotis?DaliasEmail author Giorgos?D.?Kokkoris Andreas?Y.?Troumbis 《Biology and Fertility of Soils》2003,37(2):90-95
Recent experimental evidence on the relationship between temperature and litter or soil organic matter decomposition suggests that the simple assumption that temperature affects the rate constant of the processes may not be valid. Thermal conditions seem to influence the kinetics of C mineralization by changing, in a qualitatively predictable way, the estimated percentages of initial material that behave as labile or recalcitrant. The consequences of this shift in mineralization dynamics due to temperature, referred to as the functional shift hypothesis, for the long-term C accumulation potential of a soil were investigated using a modified version of Jenny's model. It was concluded that if soils behave according to the functional shift hypothesis, then the utilization of Q10 or other temperature response functions by simulation models leads to significant overestimations of soil C losses due to temperature increase. 相似文献
64.
Peter?Schr?derEmail author Beate?Huber Jean?Charles?Munch 《Journal of Soils and Sediments》2003,3(4):223-226
All forms of agriculture cause changes in the balances and fluxes of preexisting ecosystems, thereby limiting self-regulatory
ecosystem (resiliency) functions. The intensive agriculture of the past, with its strong reduction of landscape structures
and vast decoupling of energy and matter cycles, has caused stress and degradation of the production base; massive influence
has also been exerted on neighboring compartments. This has resulted in the well known problems of pesticide loads, high phosphate
loads to surface waters via over-fertilized soils or erosion as such. To overcome the economic, social and political inadequacies
leading to ecological degradation, the demand for sustainable agricultural management needs to be transposed into knowledge-based
practical instructions and political regulations on a regional scale. Thus, applied research for a sustainable and ecologically
compatible land use aimed at sufficient food production is ever so important. In the FAM, thirty German research institutes
have merged to perform research on this topic. 相似文献
65.
66.
Kay?HamerEmail author Astrid?Hadeler Thomas?Muschalla Jürgen?Schr?ter Günter?Timmer 《Journal of Soils and Sediments》2003,3(4):284-291
Goal
Annually, 400.000 m3 harbour sediments are dredged to maintain the water depth in the harbours of Bremen and Bremerhaven. The sediment contains organic and inorganic pollutants and hence is deposited on a landfill. Because of the limited capacity of that landfill alternative treatment techniques are investigated. This study aims to evaluate the production of Light Weight Aggregates (LWA) from harbour sediments with respect to the product quality and environmental aspects of the use of the LWA. 相似文献67.
Jen JC Chan WM Bosley TM Wan J Carr JR Rüb U Shattuck D Salamon G Kudo LC Ou J Lin DD Salih MA Kansu T Al Dhalaan H Al Zayed Z MacDonald DB Stigsby B Plaitakis A Dretakis EK Gottlob I Pieh C Traboulsi EI Wang Q Wang L Andrews C Yamada K Demer JL Karim S Alger JR Geschwind DH Deller T Sicotte NL Nelson SF Baloh RW Engle EC 《Science (New York, N.Y.)》2004,304(5676):1509-1513
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing. 相似文献
68.
Rensing SA Lang D Zimmer AD Terry A Salamov A Shapiro H Nishiyama T Perroud PF Lindquist EA Kamisugi Y Tanahashi T Sakakibara K Fujita T Oishi K Shin-I T Kuroki Y Toyoda A Suzuki Y Hashimoto S Yamaguchi K Sugano S Kohara Y Fujiyama A Anterola A Aoki S Ashton N Barbazuk WB Barker E Bennetzen JL Blankenship R Cho SH Dutcher SK Estelle M Fawcett JA Gundlach H Hanada K Heyl A Hicks KA Hughes J Lohr M Mayer K Melkozernov A Murata T Nelson DR Pils B Prigge M Reiss B Renner T Rombauts S Rushton PJ 《Science (New York, N.Y.)》2008,319(5859):64-69
We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics. 相似文献
69.
Rare earth element (REE) data from two ordinary chondrite chondrules show distinct negative chondrite-normalized concentration anomalies of samarium, europium, and ytterbium. The peculiar patterns may be the result of REE gas/solid fractionation at an oxygen fugacity lower than has been assumed for the canonical solar nebula. We suggest that the two ordinary chondrite chondrules acquired the fractionated REE patterns by incorporation of highly reduced, ultrarefractory condensates in their precursors. This interpretation implies that high-temperature condensation processes occurred in nebular environments with a strong deficit in oxygen, such as regions with an enhanced carbon/oxygen ratio. 相似文献
70.