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61.
Llorenç Milà i Canals Christian Bauer Jochen Depestele Alain Dubreuil Ruth Freiermuth Knuchel Gérard Gaillard Ottar Michelsen Ruedi Müller-Wenk Bernt Rydgren 《The International Journal of Life Cycle Assessment》2007,12(1):5-15
Background, Aim and Scope
Land use by agriculture, forestry, mining, house-building or industry leads to substantial impacts, particularly on biodiversity
and on soil quality as a supplier of life support functions. Unfortunately there is no widely accepted assessment method so
far for land use impacts. This paper presents an attempt, within the UNEP-SETAC Life Cycle Initiative, to provide a framework
for the Life Cycle Impact Assessment (LCIA) of land use.
Materials and Methods:
This framework builds from previous documents, particularly the SETAC book on LCIA (Lindeijer et al. 2002), developing essential
issues such as the reference for occupation impacts; the impact pathways to be included in the analysis; the units of measure
in the impact mechanism (land use interventions to impacts); the ways to deal with impacts in the future; and bio-geographical
differentiation.
Results:
The paper describes the selected impact pathways, linking the land use elementary flows (occupation; transformation) and parameters
(intensity) registered in the inventory (LCI) to the midpoint impact indicators and to the relevant damage categories (natural
environment and natural resources). An impact occurs when the land properties are modified (transformation) and also when
the current man-made properties are maintained (occupation).
Discussion:
The size of impact is the difference between the effect on land quality from the studied case of land use and a suitable reference
land use on the same area (dynamic reference situation). The impact depends not only on the type of land use (including coverage
and intensity) but is also heavily influenced by the bio-geographical conditions of the area. The time lag between the land
use intervention and the impact may be large; thus land use impacts should be calculated over a reasonable time period after
the actual land use finishes, at least until a new steady state in land quality is reached.
Conclusions:
Guidance is provided on the definition of the dynamic reference situation and on methods and time frame to assess the impacts
occurring after the actual land use. Including the occupation impacts acknowledges that humans are not the sole users of land.
Recommendations and Perspectives:
The main damages affected by land use that should be considered by any method to assess land use impacts in LCIA are: biodiversity
(existence value); biotic production potential (including soil fertility and use value of biodiversity); ecological soil quality
(including life support functions of soil other than biotic production potential). Bio-geographical differentiation is required
for land use impacts, because the same intervention may have different consequences depending on the sensitivity and inherent
land quality of the environment where it occurs. For the moment, an indication of how such task could be done and likely bio-geographical
parameters to be considered are suggested. The recommendation of indicators for the suggested impact categories is a matter
of future research. 相似文献
62.
Data on the major histocompatibility complex, T-cell epitopes, B-cell epitopes, antigens and diseases are heterogeneous and scattered among different databases and the literature. Since it has become increasingly difficult to obtain an integrated view of functional immune response components, we have developed and updated over several years the Functional molecular IMMunology (FIMM) database (http:// research.i2r.a-star.edu.sg/fimm/). FIMM contains integrated expert-curated data on protein antigens, and on human immunological receptors that recognise and bind them in healthy or disease states. Interfaces with multiple, intuitive query options and query reports provide immunologists with prioritised information that aids data interpretation, vaccine target discovery and immune disease research. 相似文献
63.
Hernández-Hernández A Rincón-Arano H Recillas-Targa F Ortiz R Valdes-Quezada C Echeverría OM Benavente R Vázquez-Nin GH 《Chromosoma》2008,117(1):77-87
The synaptonemal complex (SC) is an evolutionarily conserved structure that mediates synapsis of homologous chromosomes during
meiotic prophase I. Previous studies have established that the chromatin of homologous chromosomes is organized in loops that
are attached to the lateral elements (LEs) of the SC. The characterization of the genomic sequences associated with LEs of
the SC represents an important step toward understanding meiotic chromosome organization and function. To isolate these genomic
sequences, we performed chromatin immunoprecipitation assays in rat spermatocytes using an antibody against SYCP3, a major
structural component of the LEs of the SC. Our results demonstrated the reproducible and exclusive isolation of repeat deoxyribonucleic
acid (DNA) sequences, in particular long interspersed elements, short interspersed elements, long terminal direct repeats,
satellite, and simple repeats. The association of these repeat sequences to the LEs of the SC was confirmed by in situ hybridization
of meiotic nuclei shown by both light and electron microscopy. Signals were also detected over the chromatin surrounding SCs
and in small loops protruding from the lateral elements into the SC central region. We propose that genomic repeat DNA sequences
play a key role in anchoring the chromosome to the protein scaffold of the SC.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
64.
We introduce a novel computational approach to predict effective genome size (EGS; a measure that includes multiple plasmid copies, inserted sequences, and associated phages and viruses) from short sequencing reads of environmental genomics (or metagenomics) projects. We observe considerable EGS differences between environments and link this with ecologic complexity as well as species composition (for instance, the presence of eukaryotes). For example, we estimate EGS in a complex, organism-dense farm soil sample at about 6.3 megabases (Mb) whereas that of the bacteria therein is only 4.7 Mb; for bacteria in a nutrient-poor, organism-sparse ocean surface water sample, EGS is as low as 1.6 Mb. The method also permits evaluation of completion status and assembly bias in single-genome sequencing projects. 相似文献
65.
66.
Darius Daunys Petras Zemlys Sergej Olenin Anastasija Zaiko Christian Ferrarin 《Helgoland Marine Research》2006,60(2):113-120
The role of the zebra mussel Dreissena polymorpha in redistribution of total particulate material (TPM) between the water column and bottom sediment was estimated using the TPM budget for a mussel bed in the Curonian lagoon, the Baltic Sea. Seasonal clearance rates were derived from the TPM budget assuming two resuspension scenarios: no resuspension and full resuspension of biodeposits. Estimated clearance rates for both scenarios were compared with the rates calculated from the population clearance rate model. Seasonal clearance rates estimated using the population model (1.1 and 11.8 l g−1 SFDW day−1) fitted well into the interval of seasonal clearance rates calculated from TPM budgets assuming no resuspension of biodeposits (3.2 and 21.4 l g SFDW−1 day−1). In the scenario with biodeposits resuspension clearance rates were much higher (57.4 and 148.9 g SFDW−1 day−1). The ratio of clearance to residence time was highly dependent on the fate of biodeposits. Therefore its use in interpretation of the species impact on TPM was limited. An alternative measure based on the ratio of the amount of TPM biodeposited to TPM transported into the bed was used. It was found that zebra mussels are able to deposit between 10 and 30% of the incoming TPM, and the amount of biodeposited material was correlated with water residence time. Results indicate that the impact of zebra mussels on TPM in the lagoon is small relative to the high transport rates of TPM over the bed. However, annual biosedimentation rate (~590 g m−2) in the mussel bed was higher than physical deposition rate (~380 g m−2) in accumulation areas devoid of large suspension feeders. We suggest that a local impact due to enhanced availability of organic material to other trophic groups of associated benthic organisms may be more significant than effects on TPM pathways at an ecosystem scale. 相似文献
67.
Ulrich Membe Femoe Hermine Boukeng Jatsa Valentin Greigert Julie Brunet Catherine Cannet Mrim Christian Kenfack Nestor Gipwe Feussom Joseph Bertin Kadji Fassi Emilenne Tienga Nkondo Ahmed Abou-Bacar Alexander Wilhelm Pfaff Thophile Dimo Pierre Kamtchouing Louis-Albert Tchuem Tchuent 《PLoS neglected tropical diseases》2022,16(4)
BackgroundOne of the considerable challenges of schistosomiasis chemotherapy is the inefficacy of praziquantel (PZQ) at the initial phase of the infection. Immature schistosomes are not susceptible to PZQ at the curative dose. Here, we investigated the efficacy of different PZQ regimens administered during the initial stage of Schistosoma mansoni infection in mice.Methodology/Principal findingsTwo months-old mice were individually infected with 80 S. mansoni cercariae and divided into one infected-untreated control group (IC) and four PZQ-treated groups: PZQ at 100 mg/kg/day for five consecutive days (group PZQ1), PZQ at 100 mg/kg/day for 28 days (group PZQ2), PZQ at 18 mg/kg/day for 28 days (group PZQ3) and a single dose of PZQ at 500 mg/kg (group PZQ4). The treatment started on day one post-infection (p.i), and each group of mice was divided into two subgroups euthanized on day 36 or 56 p.i, respectively. We determined the mortality rate, the parasitological burden, the hepatic and intestinal granulomas, the serum levels of Th-1, Th-2, and Th-17 cytokines, and gene expression. The treatment led to a significant (p < 0.001) reduction of worm burden and egg counts in the intestine and liver in groups PZQ2 and PZQ3. On 56th day p.i, there was a significant reduction (p < 0.001) of the number and volume of the hepatic granulomas in groups PZQ2 and PZQ3 compared to group PZQ1 or PZQ4. Moreover, in group PZQ3, the serum levels of IFN-γ, TNF-α, IL-13, and IL-17 and their liver mRNA expressions were significantly reduced while IL-10 and TGF-β gene expression significantly increased. The highest mortality rate (81.25%) was recorded in group PZQ2.Conclusion/SignificanceThis study revealed that the administration of PZQ at 18 mg/kg/day for 28 consecutive days was the optimal effective posology for treating S. mansoni infection at the initial stage in a murine model. 相似文献
68.
Cui W Paglialunga S Kalant D Lu H Roy C Laplante M Deshaies Y Cianflone K 《American journal of physiology. Endocrinology and metabolism》2007,293(6):E1482-E1491
Acylation-stimulating protein (ASP), a lipogenic hormone, stimulates triglyceride (TG) synthesis and glucose transport upon activation of C5L2, a G protein-coupled receptor. ASP-deficient mice have reduced adipose tissue mass due to increased energy expenditure despite increased food intake. The objective of this study was to evaluate the blocking of ASP-C5L2 interaction via neutralizing antibodies (anti-ASP and anti-C5L2-L1 against C5L2 extracellular loop 1). In vitro, anti-ASP and anti-C5L2-L1 blocked ASP binding to C5L2 and efficiently inhibited ASP stimulation of TG synthesis and glucose transport. In vivo, neither anti-ASP nor anti-C5L2-L1 altered body weight, adipose tissue mass, food intake, or hormone levels (insulin, leptin, and adiponectin), but they did induce a significant delay in TG clearance [P < 0.0001, 2-way repeated-measures (RM) ANOVA] and NEFA clearance (P < 0.0001, 2-way RM ANOVA) after a fat load. After treatment with either anti-ASP or anti-C5L2-L1 antibody there was no change in adipose tissue AMPK activity, but neutralizing antibodies decreased perirenal TG mass (-38.4% anti-ASP, -18.8% anti-C5L2, P < 0.01-0.001) and perirenal LPL activity (-75.6% anti-ASP, -72.5% anti-C5L2, P < 0.05). In liver, anti-C5L2-L1 decreased TG mass (-42.8%, P < 0.05), whereas anti-ASP increased AMPK activity (+34.6%, P < 0.001). In the muscle, anti-C5L2-L1 significantly increased TG mass (+128.0%, P < 0.05), LPL activity (+226.1%, P < 0.001), and AMPK activity (+71.1%, P < 0.01). In addition, anti-ASP increased LPL activity (+164.4, P < 0.05) and AMPK activity (+53.9%, P < 0.05) in muscle. ASP/C5L2-neutralizing antibodies effectively block ASP-C5L2 interaction, altering lipid distribution and energy utilization. 相似文献
69.
70.
Isabelle Larocque-Tobler Martin Grosjean Christian Kamenik 《Palaeogeography, Palaeoclimatology, Palaeoecology》2011,299(1-2):281-288
Calibration-in-space (i.e. modern taxonomic assemblages of biota from many lakes located along a wide temperature gradient calibrated against meteorological data) is generally used to derive species-specific optima and tolerances. This results in transfer functions which then are applied to subfossil assemblages to quantitatively reconstruct environmental variables such as air/water temperature. Developing such transfer functions is time- and money-consuming, thus many biota-inferred temperature records are either based on transfer functions from other regions which might not take into account local characteristics or are only used qualitatively. In varved Lake Silvaplana (Engadine, Switzerland), another way of obtaining quantitative climate reconstructions from taxonomical assemblages preserved in lake sediments was assessed for the past 1000 years. A calibration-in-time (i.e. taxonomic-assemblage-of-biota time series calibrated against meteorological data covering the same time period) was developed for chironomids (non-biting midges) using a weighted-average-partial-least-square (WAPLS) model and compared with a calibration-in-space model. The calibration-in-time had a weaker correlation coefficient (r2 = 0.71) than the calibration-in-space (r2 = 0.86), but the error of prediction (RMSEP = 0.58 °C) and the maximum bias (Max Bias = 0.73 °C) outperformed the statistics of the calibration-in-space (RMSEP = 1.5 °C; Max Bias = 1.72). This result is probably due to the smaller temperature gradient of the calibration-in-time (6.5 °C) than the calibration-in-space (11.5 °C). For the last 150 years, the Pearson correlation coefficient was significant between the two reconstructions (rPearson = 0.52; p < 0.01) suggesting that both models recorded a similar pattern of temperature changes. On the millennium time-scale, both models showed a warm “Medieval Climate Anomaly”, a cold “Little Ice Age” and a warming through the present with significant correlations (rPearson corrected for autocorrelation (corr) = 0.61, p < 0.01) until ca. 1780 AD and between ca. 1937 and 2000 AD (rPearson corr = 0.90, p < 0.01). The reconstructions using both models significantly diverged between ca. 1780 and 1937 AD (rPearson corr = ?0.47, p < 0.01). The results of both reconstruction methods were compared with four independent local and regional records of early instrumental and documentary data during the period of divergence. Both reconstructions showed similarities with the early instrumental/documentary records, thus it was inconclusive which of the reconstruction models provides the better estimates. However, these results suggest that a calibration-in-time can be used to reconstruct climate over the last 1000 years when no calibration-in-space is available. 相似文献