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71.
The Contribution of Agriculture,Forestry and other Land Use activities to Global Warming, 1990–2012 下载免费PDF全文
Francesco N. Tubiello Mirella Salvatore Alessandro F. Ferrara Jo House Sandro Federici Simone Rossi Riccardo Biancalani Rocio D. Condor Golec Heather Jacobs Alessandro Flammini Paolo Prosperi Paola Cardenas‐Galindo Josef Schmidhuber Maria J. Sanz Sanchez Nalin Srivastava Pete Smith 《Global Change Biology》2015,21(7):2655-2660
We refine the information available through the IPCC AR5 with regard to recent trends in global GHG emissions from agriculture, forestry and other land uses (AFOLU), including global emission updates to 2012. Using all three available AFOLU datasets employed for analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for Policy Makers, our analyses point to a down‐revision of global AFOLU shares of total anthropogenic emissions, while providing important additional information on subsectoral trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total declined over time. They indicate a decadal average of 28.7 ± 1.5% in the 1990s and 23.6 ± 2.1% in the 2000s and an annual value of 21.2 ± 1.5% in 2010. The IPCC AR5 had indicated a 24% share in 2010. In contrast to previous decades, when emissions from land use (land use, land use change and forestry, including deforestation) were significantly larger than those from agriculture (crop and livestock production), in 2010 agriculture was the larger component, contributing 11.2 ± 0.4% of total GHG emissions, compared to 10.0 ± 1.2% of the land use sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010, compared to 12% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new FAO estimates indicate that land use emissions have remained stable, at about 4.8 Gt CO2 eq yr?1 in 2012. Emissions minus removals have also remained stable, at 3.2 Gt CO2 eq yr?1 in 2012. By contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained larger than the land use sector, reaching 5.4 Gt CO2 eq yr?1 in 2012. These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade. 相似文献
72.
José Miguel Gasulla Fernando Escaso Iván Narváez Francisco Ortega José Luis Sanz 《PloS one》2015,10(12)
A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous. 相似文献
73.
Toffanello ED Perissinotto E Sergi G Zambon S Musacchio E Maggi S Coin A Sartori L Corti MC Baggio G Crepaldi G Manzato E 《PloS one》2012,7(4):e34950
Background
The role of Vitamin D in musculoskeletal functionality among elderly people is still controversial. We investigated the association between serum 25-hydroxyvitamin D (25OHD) levels and physical performance in older adults.Methods
2694 community-dwelling elderly women and men from the Progetto Veneto Anziani (Pro.V.A.) were included. Physical performances were assessed by: tandem test, 5 timed chair stands (TCS), gait speed, 6-minute walking (6 mW) distance, handgrip strength, and quadriceps strength. For each test, separate general linear models and loess plots were obtained in both genders, in relation to serum 25OHD concentrations, controlling for several potential confounders.Results
Linear associations with 25OHD levels were observed for TCS, gait speed, 6 mW test and handgrip strength, but not for tandem test and quadriceps strength. After adjusting for potential confounders, linear associations with 25OHD levels were still evident for the 6 mW distance in both genders (p = .0002 in women; <.0001 in men), for TCS in women (p = .004) and for gait speed (p = .0006) and handgrip strength (p = .03) in men. In loess analyses, performance in TCS in women, in gait speed and handgrip strength in men and in 6 mW in both genders, improved with increasing levels of 25OHD, with most of the improvements occurring for 25OHD levels from 20 to 100 nmol/L.Conclusion
lower 25OHD levels are associated with a worse coordination and weaker strength (TCS) in women, a slower walking time and a lower upper limb strength in men, and a weaker aerobic capacity (6 mW) in both genders. For optimal physical performances, 25OHD concentrations of 100 nmol/L appear to be more advantageous in elderly men and women, and Vitamin D supplementation should be encouraged to maintain their 25OHD levels as high as this threshold. 相似文献74.
Bosch L Sanz ML Montilla A Alegría A Farré R del Castillo MD 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,860(1):69-77
Protein quality was assayed by simultaneous measurement of lysine (Lys), carboxymethyllysine (CML) and lysinoalanine (LAL). GC-FID analysis of N-tert-butyl dimethylsilyl (tBDMSi) derivatives of these amino acids was undertaken. tBDMSi derivates were separated on a CP-SIL 5CB commercially fused silica capillary column (25 m x 0.25 mm i.d., 0.25 microm film thickness) employing a thermal gradient programmed from 200 to 300 degrees C. The identity of tBDMSi derivatives of Lys, CML and LAL was established by GC-MS while FID detection was employed for quantification. Analytical parameters such as linearity (lysine 350-4200 microM, LAL 3-81 microM, CML 16-172 microM), precision (1-13% variation coefficients), accuracy (85-108% average recovery) and limits of detection (lysine 0.4 mg/100 g protein, LAL 5.0 mg/100 g protein, CML 3.4 mg/100 g protein) and quantification (lysine 1.4 mg/100g protein, LAL 15.2 mg/100 g protein, CML 11.2 mg/100 g protein) were determined for validation of the analytical approach. Model systems and real foods have been studied. Kinetic of CML formation from different food proteins (BSA, soy protein, casein and gluten) was performed employing model systems. Carboxymethylation rate depended on the source of protein. Maillard reaction progressed to advanced stages damaging the protein quality of stored infant foods, soy drinks, boiled eggs and dry powdered crepes. CML values ranged from 62 to 440 mg/100 g protein were measured. LAL was also formed during boiling eggs (21-68 mg/100g protein) indicating additional damage by crosslinking reaction. In agreement, lysine content was affected by both food processing and storage. 相似文献
75.
Woods AS Marcellino D Jackson SN Franco R Ferré S Agnati LF Fuxe K 《Journal of proteome research》2008,7(8):3428-3434
Receptor heteromerization is a mechanism used by G protein-coupled receptors to diversify their properties and function. We previously demonstrated that these interactions occur through salt bridge formation between epitopes of the involved receptors. Recent studies claim that calmodulin (CaM) binds to an Arg-rich epitope located in the amino-terminus of the dopamine D(2) receptor third intracellular loop. This is the same epitope involved in adenosine A(2A)-D(2) receptor heteromerization, through Coulombic interaction between the Arg residues and a phosphorylated serine (pS) located in the medial segment of the C-terminus of the A(2A) receptor. Mass spectrometric analysis indicates that an electrostatic interaction involving the D(2) receptor Arg-rich epitope and several CaM acidic epitopes are mainly responsible for the D(2) receptor-CaM binding. CaM could also form multiple noncovalent complexes by means of electrostatic interactions with an epitope localized in the proximal segment of the C-terminus of the A(2A) receptor. Ca(2+) disrupted the binding of CaM to the D(2) but not to the A(2A) receptor epitope, and CaM disrupted the electrostatic interactions between the D(2) receptor epitope and the more distal A(2A) receptor epitope. A model is introduced with the possible functional implications of A(2A)-D(2)-CaM interactions. These in vitro findings imply a possible regulatory role for CaM in receptor heteromers formation. 相似文献
76.
Jane M. Natividad Xianxi Huang Emma Slack Jennifer Jury Yolanda Sanz Chella David Emmanuel Denou Pinchang Yang Joseph Murray Kathy D. McCoy Elena F. Verdú 《PloS one》2009,4(7)
Background and Aims
Excessive uptake of commensal bacterial antigens through a permeable intestinal barrier may influence host responses to specific antigen in a genetically predisposed host. The aim of this study was to investigate whether intestinal barrier dysfunction induced by indomethacin treatment affects the host response to intestinal microbiota in gluten-sensitized HLA-DQ8/HCD4 mice.Methodology/Principal Findings
HLA-DQ8/HCD4 mice were sensitized with gluten, and gavaged with indomethacin plus gluten. Intestinal permeability was assessed by Ussing chamber; epithelial cell (EC) ultra-structure by electron microscopy; RNA expression of genes coding for junctional proteins by Q-real-time PCR; immune response by in-vitro antigen-specific T-cell proliferation and cytokine analysis by cytometric bead array; intestinal microbiota by fluorescence in situ hybridization and analysis of systemic antibodies against intestinal microbiota by surface staining of live bacteria with serum followed by FACS analysis. Indomethacin led to a more pronounced increase in intestinal permeability in gluten-sensitized mice. These changes were accompanied by severe EC damage, decreased E-cadherin RNA level, elevated IFN-γ in splenocyte culture supernatant, and production of significant IgM antibody against intestinal microbiota.Conclusion
Indomethacin potentiates barrier dysfunction and EC injury induced by gluten, affects systemic IFN-γ production and the host response to intestinal microbiota antigens in HLA-DQ8/HCD4 mice. The results suggest that environmental factors that alter the intestinal barrier may predispose individuals to an increased susceptibility to gluten through a bystander immune activation to intestinal microbiota. 相似文献77.
78.
Spatial Heterogeneity of Bacterial Populations in Monomictic Lake Estanya (Huesca,Spain) 总被引:2,自引:0,他引:2
Bacterial population changes were investigated in the monomictic Lake Estanya by combining microscopic analysis and two molecular
methods involving the amplification of 16S rDNA genes using primers for the domain Bacteria and subsequent restriction fragment length polymorphism (PCR–RFLP) and denaturing gradient gel electrophoresis (PCR–DGGE).
Both approaches revealed the vertical distribution of predominant microbial morphotypes and phylotypes in both holomictic
and stratified periods, respectively, and showed that variations in structure and composition of bacterial populations are
occurring in this lake as a function of depth and time. Through principal component analysis (PCA), these shifts could be
related to different physicochemical parameters with temperature, oxygen concentration, and the incident light being of paramount
importance as structuring variables. Comparison of RFLP and DGGE profiles by scoring similarities using the Jaccard coefficient
and then building a multidimensional scaling map (MDS) showed equivalent results. Both techniques revealed that bacterial
populations, present in the whole water column in the holomictic period, showed a high similarity with those located in the
deeper part of the lake in the stratified period, evidencing that other factors, both biotic and abiotic, should also be considered
as a force driving change in the composition of the bacterial community. Furthermore, DGGE analysis showed that sequences
from prominent bands were affiliated to members of four major phyla of the domain Bacteria: Cyanobacteria, Bacteroidetes, Proteobacteria, and Actinobacteria, most of which corresponded to heterotrophic bacterial populations involved in carbon, sulfide, and nitrogen biogeochemical
cycles, which were indistinguishable under the light microscope. 相似文献
79.
Virulence genes and intimin types of Shiga-toxin-producing Escherichia coli isolated from cattle and beef products in Argentina. 总被引:4,自引:0,他引:4
Miguel Blanco Nora L Padola Alejandra Krüger Marcelo E Sanz Jesús E Blanco Enrique A González Ghizlane Dahbi Azucena Mora María Isabel Bernárdez Analía I Etcheverría Guillermo H Arroyo Paula M A Lucchesi Alberto E Parma Jorge Blanco 《International microbiology》2004,7(4):269-276
A total of 153 Shiga-toxin-producing Escherichia coli (STEC) isolates from feces of cattle and beef products (hamburgers and ground beef) in Argentina were characterized in this study. PCR showed that 22 (14%) isolates carried stx1 genes, 113 (74%) possessed stx2 genes and 18 (12%) both stx1 and stx2. Intimin (eae), enterohemolysin (ehxA), and STEC autoagglutinating adhesin (saa) virulence genes were detected in 36 (24%), 70 (46%) and in 34 (22%) of the isolates, respectively. None of 34 saa-positive isolates carried the gene eae, and 31 were ehxA-positive. Fourteen (7 of serotype O26:H11 and 4 of serotype O5:H-) isolates had intimin b1, 16 isolates possessed intimin g1 (11 of serotype O145:H- and 5 of serotype O157:H7), 5 isolates had intimin type e1 (4 of serotypes O103:H- and O103:H2), and one isolate O111:H- showed intimin type q/g2. Although the 153 STEC isolates belonged to 63 different seropathotypes, only 12 accounted for 58% of isolates. Seropathotype ONT:H- stx2 (18 isolates) was the most common, followed by O171:H2 stx2 (12 isolates), etc. The majority (84%) of STEC isolates belonged to serotypes previously found in human STEC and 56% to serotypes associated with STEC isolated from patients with hemolytic uremic syndrome (HUS). Thus, this study confirms that cattle are a major reservoir of STEC pathogenic for humans. To our knowledge, this is the first study that described the presence of saa gene in STEC of serotypes O20:H19, O39:H49, O74:H28, O79:H19, O116:H21, O120:H19, O141:H7, O141:H8, O174:H21, and ONT:H21. The serotypes O120:H19 and O185:H7 were not previously reported in bovine STEC. 相似文献
80.
Structural studies of the lysozyme coded by the pneumococcal phage Cp-1. Conformational changes induced by choline 总被引:2,自引:0,他引:2
The CPL-1 lysozyme coded by the pneumococcal phage Cp-1 has been overproduced in Escherichia coli under the control of a modified lipoprotein lactose promoter. This result has provided the conditions to analyse the CPL-1 secondary structure by circular dichroism (CD). The CD spectra recorded in the far-ultraviolet region showed, at neutral pH, two minima at 210 nm and 230 nm and a shoulder at 217 nm, whereas two bands at 260 nm and 295 nm were observed in the near-ultraviolet region. It has been estimated, by using the CDPROT program, that the protein is composed of 19% alpha-helix, 32% beta-sheet, 28% beta-turn and 21% random coil. Minor changes in the CD spectra were detected either when the pH was varied over 6-10 or when the ionic strength was increased to 1 M NaCl. Choline, a well known modulator of the enzyme activity that is present in the pneumococcal cell wall, induced remarkable changes in the intensities of the bands at 210, 230 and 295 nm, with the appearance of an unusual positive band at 225 nm. The conformational change was reversible and correlated with the competitive inhibitory effect of choline on the lysozyme activity, supporting, by a new and direct experimental approach, the basic role of choline in the recognition of the cell wall substrate. The analyses of the secondary structure prediction and the CD data reported here are compatible with the two-domain structure of CPL-1 reinforce our hypothesis that the C-terminal region is directly involved in the binding of the enzyme to the pneumococcal teichoic and lipoteichoic acids. 相似文献