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101.
Forest liming is a common measure to counteract soil acidification. In forest practice, lime is applied to the forest floor where it changes the chemical properties. However, little is known about the depth impact of liming and the depth translocation of lime components. To investigate the long-term impact of forest liming, several study plots have been established in the 1980s in Germany in stands with different site conditions. We analysed soil chemical data obtained during the last 28?years from 45 of the study plots. We examined the depth impact of liming and predicted the main factors responsible for the increase in Calcium (Ca) and Magnesium (Mg) stocks after liming in the mineral soil using multiple linear regression analyses (MLR). Stocks of Ca and Mg as well as base saturation (BS) showed a strong depth gradient with significant differences between limed and control plots down to 40?cm of the mineral soil. About 65–70?% of applied Ca and Mg were recovered in the forest floor and the upper 40?cm of the mineral soil. BS in 0–40?cm increased by a mean of 11?%. MLR models could explain 48–74?% of the variation in mean changes of Ca and Mg in 0–10, 10–20 and 20–40?cm soil depth when soil and climate variables, amount of applied lime and years after liming are included in the model. After testing the model robustness with a cross-validating procedure, we concluded that these models might be applied to many regions in Central Europe with comparable soil and climate conditions and thus, have widespread application.  相似文献   
102.
Multispectral images (0.44 to 0.98 μm) of asteroid (4) Vesta obtained by the Dawn Framing Cameras reveal global color variations that uncover and help understand the north-south hemispherical dichotomy. The signature of deep lithologies excavated during the formation of the Rheasilvia basin on the south pole has been preserved on the surface. Color variations (band depth, spectral slope, and eucrite-diogenite abundance) clearly correlate with distinct compositional units. Vesta displays the greatest variation of geometric albedo (0.10 to 0.67) of any asteroid yet observed. Four distinct color units are recognized that chronicle processes--including impact excavation, mass wasting, and space weathering--that shaped the asteroid's surface. Vesta's color and photometric diversity are indicative of its status as a preserved, differentiated protoplanet.  相似文献   
103.
Structure determination of proteins and other macromolecules has historically required the growth of high-quality crystals sufficiently large to diffract x-rays efficiently while withstanding radiation damage. We applied serial femtosecond crystallography (SFX) using an x-ray free-electron laser (XFEL) to obtain high-resolution structural information from microcrystals (less than 1 micrometer by 1 micrometer by 3 micrometers) of the well-characterized model protein lysozyme. The agreement with synchrotron data demonstrates the immediate relevance of SFX for analyzing the structure of the large group of difficult-to-crystallize molecules.  相似文献   
104.
Phospholipase C zeta (PLCz) and cyclooxygenase isoenzyme type 2 (COX-2) are important in spermatogenesis, but their effect has not yet confirmed in pigs. Therefore, this study was aimed to analyse their association with sperm quality and fertility and to identify the mRNA and protein expression in boars reproductive tissues. DNA samples from 231 Pietrain (PI) and 109 Pietrain × Hampshire (PIHA) pigs with records of sperm quality [sperm concentration (SCON), motility, semen volume, plasma droplet and abnormal spermatozoa rate] and fertility (non-return rate and number of piglet born alive) traits were available. A SNP in non-coding region of PLCz g.158 A > C was associated with SCON (p < 0.05) in PIHA population while the polymorphism of COX-2 g.68 G > A in 3' UTR was not associated with any traits. For mRNA and protein expression study, a total of six boars were divided into two groups with G-I and G-II, where G-I was characterized for relatively better sperm quality. Both genes expressed higher in reproductive tissues compared with non-reproductive tissues. Phospholipase C zeta mRNA expressed higher in testis (p < 0.01), all parts of epididymis and spermatozoa from G-I, while COX-2 expressed higher in testis (p < 0.05), head and body of epididymis (p < 0.01), and spermatozoa from G-II boar. Both proteins were localized in Leydig cells and spermatozoa. These results might shed light on roles of these genes in spermatogenesis as candidate for boar sperm quality and fertility, but still the lack of association across populations should be considered.  相似文献   
105.
Toll-like receptors (TLR) are relevant for piscine innate immunity. TLR activation recruits several downstream factors regulating the expression of immunorelevant genes. We have characterized two key factors of innate immunity from rainbow trout: MyD88 as an adaptor protein interacting directly with TLRs, and serum amyloid A as an effector molecule induced by the activated Toll-like receptor signaling cascade.Both factors share a remarkable high degree of structural conservation with their mammalian orthologs suggesting that innate immune defense mechanisms may also functionally be conserved between fish and mammals.  相似文献   
106.
This is a case report of enteric protothecosis caused by Prototheca zopfii in an eight-year-old male mixed breed dog with a history of chronic bloody diarrhea, loss of appetite and weight loss. Algae were isolated from rectal scrapings in defibrinated sheep blood agar and dextrose Sabouraud agar. Cytological evaluation showed the presence of globular and cylindrical organisms with a defined capsule and variable number of endospores, characteristic of the genus Prototheca, in the rectum of the animal. Scanning electron microscopy of P. zopfii strains at different development stages confirmed the diagnosis of algal infection. Molecular identification using a conserved 18S rDNA gene sequence determined that the strain belonged to genotype 2. This report describes success on treatment of canine protothecosis, diagnosed based on clinical, cytological, microbiological, scanning electron microscopy and genotypical findings.  相似文献   
107.
108.
Nitrogen (N) fluxes of a slope mire in the German Harz Mountains were monitored to study the effect of increased N deposition on the N retention of the mire. In addition, the N content of mire pore water beneath different plant species was analyzed to assess N retention ability of plants. Atmospheric N deposition at the study site was 4.9?±?0.4 g N m?2 year?1 averaged for the study period of 2002 and 2003, with forest stand deposition being the largest share. Discharge was the main output pathway of N with a rate of 1.9?±?0.3 g N m?2 year?1. The mire showed a high N retention rate of 67%. Short-term N accumulation rate was 3.9 g N m?2 year?1. Differences in mire pore water N concentration under different vegetation cover indicate a lower N retention ability for ombrotrophic Sphagnum plants.  相似文献   
109.
<正>在上世纪20年代一些测试方法开始发展,这些方法现在被统称为图像成形法(Picture forming methods)。其中最具代表意义的是氯化铜结晶法(copper chloride crystal-  相似文献   
110.
Selection and establishment of reserves was often done unplanned and uncoordinated between regions. Systematic conservation planning provides tools to identify optimally located priority areas for conservation. Planning for multiple species promises adequate provision for the needs of a range of threatened species simultaneously. Several studies apply the set-covering problem by minimizing resources for given conservation targets of multiple species. We extend this method by also considering different degrees of coordination in multiple-species conservation planning and representing reserve sizes endogenously. A deterministic, spatially explicit programming model solved with mixed integer programming is used to represent minimum habitat area thresholds for all included biodiversity features. The empirical model application to European wetland species addresses five different scenarios of coordination in conservation planning, including taxonomic, political, and biogeographical coordination of planning. Our approach illustrates and quantifies the efficiency of multi-species conservation activities. We show that maximum coordination in conservation planning enhances area efficiency by 30% compared to no coordination. Furthermore, strong coordination in conservation planning does not only reduce the area requirement, but synergy effects even enable the conservation features to achieve higher conservation objectives. Spatial subdivision of planning, however, leads to highest area requirements and less conservation target achievement.  相似文献   
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