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111.
Tommaso Chiti Lorenzo Gardin Lucia Perugini Roberta Quaratino Francesco Primo Vaccari Franco Miglietta Riccardo Valentini 《Biology and Fertility of Soils》2012,48(1):9-17
The aim of this work was to quantify the soil organic C (SOC) stock in the top 30 cm of mineral soil for the whole Italian
territory, according to the different land use types of the Intergovernmental Panel on Climate Change (IPCC) cropland category
(arable land, agroforestry, vineyards, olive groves, orchards and rice fields), as a basis for future land use scenarios and
to address mitigation policy at country level. A database for SOC stock was created with the data from the national project
denominated SIAS and partly from regional map reports. All data were referred to the year 2000 since they were derived from
surveys conducted from 1995 to 2005. The data were stratified according to the Italian climatic regions, the landscape position
and the IPCC cropland subcategories. Taking into account the uncertainty in the estimate, the mean SOC stock values of the
different subcategories show significant differences (p < 0.05) among climatic regions and landscapes, ranging from 41.9 ± 15.9 Mg C ha−1 in the vineyards to 63.3 ± 27.9 Mg C ha−1 in the rice fields. Generally, a small decrease of the SOC stock from the temperate regions toward the Mediterranean ones
is observed. Taking into account the mean value of each subcategory and the country area they occupied in 2000, the total
C stored in the upper 30 cm of soil was estimated at 490.0 ± 121.7 Tg C. The resulting estimate represents the 17% of the
value reported by another study for the soil of the whole country down to 50 cm depth, suggesting the importance of preserving
this large C pool. Considering the cropland category as a whole, the estimated mean SOC stock is 52.1 ± 17.4 Mg C ha−1, similar to that reported for other European countries, 50–60 Mg C ha−1. In conclusion, the assessment of the mean SOC stock of the different cropland land uses, landscape position and climate
regions could notably help when assessing the impact of different agricultural practices and future stock change evaluation. 相似文献
112.
113.
Skiöldebrand E Lorenzo P Zunino L Rucklidge GJ Sandgren B Carlsten J Ekman S 《Equine veterinary journal》2001,33(4):394-402
The aim of the present investigation was to study the metabolic activity of the third carpal bone and the release of COMP, aggrecan and collagen type II molecules in the synovial fluid as a result of injury. Cartilage oligomeric matrix protein (COMP), aggrecan and collagen type II or fragments of these molecules released to the synovial fluid and serum (COMP) were quantified in samples from 73 left equine middle carpal joints from 2 breeds with different activity profiles (52 Standardbred trotters [STB] and 21 Swedish Warmblood riding horses [SWH]) and different articular cartilage lesions. Synovial and serum samples were analysed using inhibition ELISA for COMP and aggrecan. An ELISA that combines features of both the competitive and capture ELISAs was used for collagen type II. COMP and aggrecan concentrations decreased in synovial fluid from the joints with moderate lesions of STB compared with the normal joints; COMP from 16.6 to 12.0 microg/ml and aggrecan from 93.0 to 68.1 microg/ml. In serum, COMP concentrations were also lowered in the STB with moderate lesions compared with the normal joints, while in the SWH, the COMP concentration in synovial fluids from joints with moderate lesions was somewhat increased at 19.6 microg/ml compared with the normal joints (17.6 microg/ml). The ratio between aggrecan/COMP in the synovial fluid from joints with moderate lesions was higher in the STB (6.2) than in the SWH (3.4). The level of collagen type II in synovial fluid was higher in the SWH (8.8 microg/ml) than the STB (1.6 microg/ml), but there was no correlation between joint damage and collagen concentrations in synovial fluids (10.0 and 1.8 microg/ml in joints with moderate lesions from SWH and STB, respectively). A marked difference in COMP synthesised upon metabolic labelling between the normal and osteoarthritic cartilage was seen and the synthesis of COMP in the articular cartilage of the third carpal bone with moderate articular lesions (from an STB) was lower than in the joint with mild lesions. This difference between breeds may reflect different load characters, in release of macromolecules in osteoarthritic and normal joints. This a novel finding that should be considered in studies of equine traumatic arthritis. 相似文献
114.
The furcation region morphology was evaluated in 103 mature feline carnassial teeth (54 maxillary fourth premolar and 49 mandibular first molar teeth). Patent furcation canals were present in 27.2% of teeth. No significant difference (p = 0.88) in distribution of this anatomical variation was found between maxillary fourth premolar and mandibular first molar teeth. The mean width of these furcation canals was 104.0 microns with two-thirds of the canals having a buccal orientation. The presence of furcation canals could be a factor in the etiopathogenesis of feline dental resorptive lesions, as well as a characteristic to be considered in the diagnosis, prognosis, and treatment of endodontic or periodontic-endodontic lesions in cat teeth. 相似文献
115.
A six-year-old cross breed dog was presented with a four-month history of seizure activity, which was unresponsive to anticonvulsive therapy and an acute deterioration in neurological status, evident as central blindness. Cyst-like structures and nodular enhancement within the subarachnoid space were shown on a magnetic resonance image (MRI) scan. Histopathological examination of brain tissue was consistent with meningeal carcinomatosis. 相似文献
116.
Alterations of mitochondrial functions are linked to multiple degenerative or acute diseases. As mitochondria age in our cells, they become progressively inefficient and potentially toxic, and acute damage can trigger the permeabilization of mitochondrial membranes to initiate apoptosis or necrosis. Moreover, mitochondria have an important role in pro-inflammatory signaling. Autophagic turnover of cellular constituents, be it general or specific for mitochondria (mitophagy), eliminates dysfunctional or damaged mitochondria, thus counteracting degeneration, dampening inflammation, and preventing unwarranted cell loss. Decreased expression of genes that regulate autophagy or mitophagy can cause degenerative diseases in which deficient quality control results in inflammation and the death of cell populations. Thus, a combination of mitochondrial dysfunction and insufficient autophagy may contribute to multiple aging-associated pathologies. 相似文献
117.
Quantum mechanics, through the Heisenberg uncertainty principle, imposes limits on the precision of measurement. Conventional measurement techniques typically fail to reach these limits. Conventional bounds to the precision of measurements such as the shot noise limit or the standard quantum limit are not as fundamental as the Heisenberg limits and can be beaten using quantum strategies that employ "quantum tricks" such as squeezing and entanglement. 相似文献
118.
Sanchez-Ballesta MT Rodrigo MJ Lafuente MT Granell A Zacarias L 《Journal of agricultural and food chemistry》2004,52(7):1950-1957
A cDNA encoding a dehydrin was isolated from the flavedo of the chilling-sensitive Fortune mandarin fruit (Citrus clementina Hort. Ex Tanaka x Citrus reticulata Blanco) and designed as Crcor15. The predicted CrCOR15 protein is a K2S member of a closely related dehydrin family from Citrus, since it contains two tandem repeats of the unusual Citrus K-segment and one S-segment (serine cluster) at an unusual C-terminal position. Crcor15 mRNA is consistently and highly expressed in the flavedo during fruit development and maturation. The relative abundance of Crcor15 mRNA in the flavedo was estimated to be higher than 1% of total RNA. The high mRNA level remained unchanged during fruit storage at chilling (2 degrees C) and nonchilling (12 degrees C) temperatures, and it was depressed by a conditioning treatment (3 days at 37 degrees C) that induced chilling tolerance. Therefore, the expression of Crcor15 appears not to be related to the acquisition of chilling tolerance in mandarin fruits. However, Crcor15, which was barely detected in unstressed mandarin leaves, was rapidly induced in response to both low temperature and water stress. COR15 protein was expressed in Escherichia coli, and the purified protein conferred in vitro protection against freezing and dehydration inactivation. The potential role of Citrus COR15 is discussed. 相似文献
119.
Cantos E Espín JC López-Bote C de la Hoz L Ordóñez JA Tomás-Barberán FA 《Journal of agricultural and food chemistry》2003,51(21):6248-6255
The aim of the present work was to identify and quantify the phenolic compounds and fatty acids in acorns from Quercus ilex, Quercus rotundifolia, and Quercus suber. The concentration of oleic acid was >63% of total fatty acids in all cases, followed by palmitic and linoleic acids at similar concentrations (12-20%). The concentrations of alpha-tocopherol in Q. rotundifolia, Q. ilex, and Q. suber were 19, 31, and 38 mg/kg of dry matter (DM), respectively, whereas the concentrations of gamma-tocopherol were 113, 66, and 74 mg/kg of DM, respectively. Thirty-two different phenolic compounds were distinguished. All of them were gallic acid derivatives, in the form of either galloyl esters of glucose, combinations of galloyl and hexahydroxydiphenoyl esters of glucose, tergallic O- or C-glucosides, or ellagic acid derivatives. Several tergallic acid C-glucosides were also present in the extracts obtained from Q. suber. Acorns from Q. ilex and Q. rotundifolia showed similar polyphenol patterns mainly with gallic acid-like spectra. Chromatograms of Q. suber showed mainly polyphenols with ellagic acid-like spectra. Valoneic acid dilactone was especially abundant in Q. suber skin. The contribution of skin to the total phenolics of the acorn was relatively small in Q. rotundifolia and Q. ilex but relatively high in Q. suber. Skin extracts from Q. suber, Q. rotundifolia, and Q. ilex showed 1.3, 1.4, and 1.0 antioxidant efficiencies, respectively (compared to that of butylhydroxyanisole). Endosperm extracts showed lower capacity to prevent lipid peroxidation than skin extracts. 相似文献
120.
López C Torrado A Fuciños P Guerra NP Pastrana L 《Journal of agricultural and food chemistry》2004,52(10):2907-2914
The enzymatic hydrolysis of starch present in chestnut purée was performed through a one-step treatment with a mixture of a commercial thermostable alpha-amylase (Termamyl 120 L, type S) and glucoamylase (AMG 300 L) at 70 degrees C. The effect of the enzyme concentration and the ratio of both amylases in the reaction mixture was studied by means of a factorial second-order rotatable design, which allowed conditions to be set leading to the total conversion of starch to glucose after 15 min of incubation (60 total enzymatic units g(-1) of chestnut; ratio of alpha-amylase/glucoamylase enzymatic units, 0.35:0.65). At lower enzyme concentration, the delay in the addition of the glucoamylase with regard to the addition of the alpha-amylase allowed a slightly higher hydrolysis percentage to be reached when compared to the simultaneous addition of both amylases at the same low enzyme concentration. The kinetics of liberation of glucose supports the existence of a synergistic effect between these two enzymes only in the first moments of the reaction. Finally, a sequential one-step hydrolysis was assayed, and more concentrated glucose syrups were thus obtained. 相似文献