Breeding bird response to partially harvested riparian management zones     

Christopher J. Chizinski  Anna PetersonJoAnn Hanowski  Charles R. BlinnBruce Vondracek  Gerald Niemi 《Forest Ecology and Management》2011,261(11):1892-1900

We compared avian communities among three timber harvesting treatments in 45-m wide even-age riparian management zones (RMZs) placed between upland clearcuts and along one side of first- or second-order streams in northern Minnesota, USA. The RMZs had three treatments: (1) unharvested, (2) intermediate residual basal area (RBA) (targeted goal 11.5 m²/ha, realized 16.0 m²/ha), and (3) low RBA (targeted goal 5.7 m²/ha, realized 8.7 m²/ha). Surveys were conducted one year pre-harvest and three consecutive years post-harvest. There was no change in species richness, diversity, or total abundance associated with harvest but there were shifts in the types of birds within the community. In particular, White-throated Sparrows (Zonotrichia albicollis) and Chestnut-sided Warblers (Dendroica pensylvanica) increased while Ovenbirds (Seiurus aurocapilla) and Red-eyed Vireos (Vireo olivaceus) decreased. The decline of avian species associated with mature forest in the partially harvested treatments relative to controls indicates that maintaining an unharvested RMZ adjacent to an upland harvest may aid in maintaining avian species associated mature forest in Minnesota for at least three years post-harvest. However, our observations do not reflect reproductive success, which is an area for future research.  相似文献   

Synthesis of the sednet work package 5 outcomes     

Susanne Heise  Sabine E. Apitz  Marc Babut  Helge Bergmann  Piet den Besten  Gerald J. Ellen  Jan Joziasse  Alexandra Katsiri  Vera Maaß  Amy Oen  Adriaan Slob  Sue White 《Journal of Soils and Sediments》2004,4(4):233-235

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Comparison of modeling approaches to quantify residue architecture effects on soil temperature and water     

Joseph A. Kozak  Robert M. Aiken  Gerald N. Flerchinger  David C. Nielsen  Liwang Ma  Lajpat Ahuja 《Soil & Tillage Research》2007,95(1-2):84-96

RZ-SHAW is a hybrid model, comprised of modules from the Simultaneous Heat and Water (SHAW) model integrated into the Root Zone Water Quality Model (RZWQM) that allows more detailed simulation of different residue types and architectures that affect heat and water transfer at the soil surface. RZ-SHAW allows different methods of surface energy flux evaluation to be used: (1) the SHAW module, where evapotranspiration (ET) and soil heat flux are computed in concert with a detailed surface energy balance; (2) the Shuttleworth–Wallace (S–W) module for ET in which soil surface temperature is assumed equal air temperature; and (3) the PENFLUX module, which uses a Penman transformation for a soil slab under incomplete residue cover. The objective of this study was to compare the predictive accuracy of the three RZ-SHAW modules to simulate effects of residue architecture on net radiation, soil temperature, and water dynamics near the soil surface. The model was tested in Akron, Colorado in a wheat residue-covered (both standing and flat) no-till (NT) plot, and a reduced till (RT) plot where wheat residue was incorporated into the soil. Temperature difference between the soil surface and ambient air frequently exceeded 17 °C under RT and NT conditions, invalidating the isothermal assumption employed in the S–W module. The S–W module overestimated net radiation (R_n) by an average of 69 Wm⁻² and underestimated the 3-cm soil temperature (T_s3) by 2.7 °C for the RT plot, attributed to consequences of the isothermal assumption. Both SHAW and PENFLUX modules overestimated midday T_s3 for RT conditions but underestimated T_s3 for NT conditions. Better performances of the SHAW and PENFLUX surface energy evaluations are to be expected as both approaches are more detailed and consider a more discretized domain than the S–W module. PENFLUX simulated net radiation slightly better than the SHAW module for both plots, while T_s3 was simulated the best by SHAW, with a mean bias error of +0.1 °C for NT and +2.7 °C for RT. Simulation results for soil water content in the surface 30 cm (θ_v30) were mixed. The NT conditions were simulated best by SHAW, with mean bias error for θ_v30 within 0.006 m³ m⁻³; RT conditions were simulated best by the PENFLUX module, which was within 0.010 m³ m⁻³.  相似文献   

Host resistance to lung infection mediated by major vault protein in epithelial cells     

Kowalski MP  Dubouix-Bourandy A  Bajmoczi M  Golan DE  Zaidi T  Coutinho-Sledge YS  Gygi MP  Gygi SP  Wiemer EA  Pier GB 《Science (New York, N.Y.)》2007,317(5834):130-132

The airway epithelium plays an essential role in innate immunity to lung pathogens. Ribonucleoprotein particles primarily composed of major vault protein (MVP) are highly expressed in cells that encounter xenobiotics. However, a clear biologic function for MVP is not established. We report here that MVP is rapidly recruited to lipid rafts when human lung epithelial cells are infected with Pseudomonas aeruginosa, and maximal recruitment is dependent on bacterial binding to the cystic fibrosis transmembrane conductance regulator. MVP was also essential for optimal epithelial cell internalization and clearance of P. aeruginosa. These results suggest that MVP makes a substantial contribution to epithelial cell-mediated resistance to infection.  相似文献   

A well-preserved Archaeopteryx specimen with theropod features     

Mayr G  Pohl B  Peters DS 《Science (New York, N.Y.)》2005,310(5753):1483-1486

A nearly complete skeleton of Archaeopteryx with excellent bone preservation shows that the osteology of the urvogel is similar to that of nonavian theropod dinosaurs. The new specimen confirms the presence of a hyperextendible second toe as in dromaeosaurs and troodontids. Archaeopteryx had a plesiomorphic tetraradiate palatine bone and no fully reversed first toe. These observations provide further evidence for the theropod ancestry of birds. In addition, the presence of a hyperextendible second toe blurs the distinction of archaeopterygids from basal deinonychosaurs (troodontids and dromaeosaurs) and challenges the monophyly of Aves.  相似文献   

A SNP map of the rat genome generated from cDNA sequences   总被引：1，自引：0，他引：1  

Zimdahl H  Nyakatura G  Brandt P  Schulz H  Hummel O  Fartmann B  Brett D  Droege M  Monti J  Lee YA  Sun Y  Zhao S  Winter EE  Ponting CP  Chen Y  Kasprzyk A  Birney E  Ganten D  Hubner N 《Science (New York, N.Y.)》2004,303(5659):807

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Human acid phosphatase in somatic cell hybrids   总被引：3，自引：0，他引：3  

G A Bruns  P S Gerald 《Science (New York, N.Y.)》1974,184(135):480-482

The human enzyme, lysosomal acid phosphatase ACP2, is expressed in nan-rodent somatic cell hybrids as a dimeric molecule. The human-rodent heteropolymer, as well as the human and rodent homopolymer, is associated with lysosomes in these cells. The genes specifying lysosomal acid phosphatase ACP(2) and LDH A are syntenic.  相似文献   

Cell signaling. Nuclear actin as choreographer of cell morphology and transcription     

Wu JI  Crabtree GR  Crabtee GR 《Science (New York, N.Y.)》2007,316(5832):1710-1711

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Climate data challenges in the 21st century     

Overpeck JT  Meehl GA  Bony S  Easterling DR 《Science (New York, N.Y.)》2011,331(6018):700-702

Climate data are dramatically increasing in volume and complexity, just as the users of these data in the scientific community and the public are rapidly increasing in number. A new paradigm of more open, user-friendly data access is needed to ensure that society can reduce vulnerability to climate variability and change, while at the same time exploiting opportunities that will occur.  相似文献   

Immunology. Decoding calcium signaling     

Winslow MM  Crabtree GR 《Science (New York, N.Y.)》2005,307(5706):56-57

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