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Elisa Karen Silva Ramos Rafael Félix de Magalhães Eloisa Helena Reis Sari Augusto Henrique Batista Rosa Paulo Christiano Anchietta Garcia Fabrício Rodrigues Santos 《Conservation Genetics》2018,19(1):99-110
Pithecopus megacephalus is a reticulated monkey–frog species endemic to the highlands of the Espinhaço Mountain Range in southeastern Brazil, an important centre of endemism in South America. This species has a discontinuous distribution and is considered “data-deficient” by the IUCN Red List, raising concerns about its conservation. Understanding the historical dynamics and connectivity of P. megacephalus populations can provide guidelines for preservation of this species in the wild. To investigate the population dynamics of P. megacephalus, we obtained multilocus DNA data for 55 individuals from different locations along the species’ known distribution. Spatial population structure, genetic diversity and demographic parameters were evaluated using population genetic and phylogeographical tools. We also evaluated its extent of occurrence and area of occupancy to investigate extinction risk of this species. We found genetic structure along P. megacephalus’ spatial distribution in the South Espinhaço Mountain Range corresponding to three population groups: northern, central and southern. Our results could provide important data on geographic distribution and population dynamics for a Data Deficient species. Therefore, we suggest these population data, together with the species’ limited occurrence in sky island environments could be used for a more accurate classification of P. megacephalus in the IUCN list, and conservation strategies for the species should be planned accordingly. 相似文献
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Silvia M. Sirchia Emanuela Orpianesi Vera Grande Patrizia Colapietro Eloisa Chiaramonte Anna Maria Di Giulio Alfredo Gorio 《Journal of cellular and molecular medicine》2014,18(5):766-779
Tuberous sclerosis complex (TSC) is caused by mutations in TSC1 or TSC2 genes. Lymphangioleiomyomatosis (LAM) can be sporadic or associated with TSC and is characterized by widespread pulmonary proliferation of abnormal α‐smooth muscle (ASM)‐like cells. We investigated the features of ASM cells isolated from chylous thorax of a patient affected by LAM associated with TSC, named LAM/TSC cells, bearing a germline TSC2 mutation and an epigenetic defect causing the absence of tuberin. Proliferation of LAM/TSC cells is epidermal growth factor (EGF)‐dependent and blockade of EGF receptor causes cell death as we previously showed in cells lacking tuberin. LAM/TSC cells spontaneously detach probably for the inactivation of the focal adhesion kinase (FAK)/Akt/mTOR pathway and display the ability to survive independently from adhesion. Non‐adherent LAM/TSC cells show an extremely low proliferation rate consistent with tumour stem‐cell characteristics. Moreover, LAM/TSC cells bear characteristics of stemness and secrete high amount of interleukin (IL)‐6 and IL‐8. Anti‐EGF receptor antibodies and rapamycin affect proliferation and viability of non‐adherent cells. In conclusion, the understanding of LAM/TSC cell features is important in the assessment of cell invasiveness in LAM and TSC and should provide a useful model to test therapeutic approaches aimed at controlling their migratory ability. 相似文献
144.
In male sand skate Psammobatis extenta , from the commercial fishery of Puerto Quequén, Argentina, six of 13 proportional dimensions analysed were constant (isometric) with total length, while seven proportions remained constant in females. The nature of the allometric and isometric relationships of disc length, disc width, interspiracular distance and interorbital distance did not vary between the sexes, and no sexual dimorphism occurred between these morphometric dimensions. A stepwise discriminant function analysis separated the sexes and was able to correctly classify 90·8% of the original grouped cases. The variables that best discriminated between sexes were prenasal length, distance from the cloaca to caudal fin tip, and distance from the snout to cloaca. The study also revealed that several of the meristic characters studied showed much intraspecific variation and, therefore, should be used with caution in taxonomic studies. 相似文献
145.
Environmental effects from a recycling rate increase of cardboard of aseptic packaging system for milk using life cycle approach 总被引:2,自引:1,他引:1
Anna Lúcia Mourad Eloisa E. C. Garcia Gustavo Braz Vilela Fernando von Zuben 《The International Journal of Life Cycle Assessment》2008,13(2):140-146
Goal, Scope and Background Despite the well-known advantages of recycling materials to reduce solid waste or save natural resources, the recycling stage
is an additional process within the life cycle that has its own energy and input requirements, as well as specific emissions.
The objective of the present paper is to analyze the life cycle inventory associated with the increase in recycling rate (from
2% up to 22% at present) of the cardboard contained in the aseptic packaging for long-life milk. The main aspects of the manufacturing
of the Tetra Pak aseptic package, including the filling of the product, the distribution of the conditioned product, up to
the final disposal and recycling rates, were considered.
Materials and Methods This study was conducted in accordance with the general directives of the ISO 14040 series. The packaging material system
was assessed using 1000 liters of milk as a functional unit, in a packaging system containing 12 units of 1 L cartons each,
placed on a corrugated paperboard tray wrapped in polyethylene shrink film and arranged onto one-way wooden pallets. Brazilian
inventories for energy, carton, corrugated paperboard and aluminum, based on site-collected data were employed. The final
disposal of used packages was modeled using the Average Brazilian Municipal Solid Waste Management data collected for the
purpose of the census of the year 2000.
Results Comparison of the total energy consumption throughout the whole life cycle of two recycling scenarios (i.e. different recycling
rates) analyzed shows that the higher recycling rate led to a 6% reduction of the total energy requirement for the long-life
milk package material system. The most significant reductions in the consumption of natural resources were: 8% water, 11%
wood and 10% land use savings. Greenhouse gases were the main reduced air emissions and contributed with a reduction of 9.7%
in GWP. Most water emissions were reduced: 10% COD, 9% BOD and 6% TSS. A unique drawback directly caused by the increase of
the recycling rate was an increase of 14.4 g in TDS emissions (57%).
Discussion The reduction in energy requirements are related and limited to the proportionality among the different materials that make
up the packaging system. Most emission reductions result from the replacement of virgin materials with recycled materials
in the packaging system. Although the average balance of water emissions is positive, the need to improve wastewater treatment
processes in the paper recycling plants to reduce TDS is highlighted as a key issue.
Conclusions It may be concluded that the increase in the recycling rate brings about a series of benefits in terms of reduction of energy
and natural resource consumption, air pollutants and most water emissions. In this case, the increase of the recycling rate
improved the overall environmental performance of the aseptic Tetra Pak system for milk.
Recommendations and Perspectives The authors are currently analyzing alternative recycling scenarios that will enable one to evaluate maximum reduction in
GWP. Further studies could include the agriculture stages, livestock and consumer phase to broaden the environmental evaluation.
ESS-Submission Editor: Dr. Andreas A. Detzel (andreas.detzel@ifeu.de) 相似文献
146.
A Synechocystis 6803 mutant carrying a chimaeric photosystem II (PSII), in which the Zea mays PsbH subunit (7.7 kDa calculated molecular mass) replaces the cyanobacterial copy (7.0 kDa), was constructed. With the exception of the N-terminal 12 amino acid extension, which has a phosphorylatable threonine, the eukaryotic polypeptide is 78% homologous to its bacterial counterpart. Biochemical characterization of this mutant shows that it expresses the engineered gene correctly and is competent for photoautotrophic growth. Fluorescence analysis and oxygen evolution measurements in the presence of exogenous acceptors indicate that the observed phenotype results from a chimaeric PSII rather than from the absence of function associated with PsbH, suggesting that the heterologous protein is assembled into a functional PSII. Inhibition of oxygen evolution by herbicides belonging to different classes shows that the sensitivity of the mutant PSII is changed only towards phenolic compounds. This result indicates slight conformational modification of the QB/herbicide binding pocket of the D1 polypeptide caused by the bulky PsbH protein in the mutant, and also suggests close structural interaction of the D1 and PsbH subunits in the topological arrangement of PSII. 相似文献
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Pinot Franck Caldas Eloisa D. Schmidt Christina Gilchrist David G. Jones A.D. Hammock Bruce D. Winter Carl K. 《Mycopathologia》1997,140(1):51-58
Using trans-diphenylpropane oxide (tDPPO) as a substrate, we measured epoxide hydrolase (EH) activity in subcellular fractions
of Alternaria alternata f. sp. lycopersici (Aal), a fungus that produces host-specific toxins. The activity was mainly (>99.5%)
located in the soluble fraction (100,000 × g supernatant) with the optimum pH at 7.4. An increase of toxin production between
days 3 and 9 found in a Aal liquid culture over a 15 days period was concomitant with a period of high EH activity. EH activity
remained constant during the same period in an Alternaria alternata culture, a fungus which does not produce toxin. In vivo
treatment of Aal culture with the peroxisome proliferator clofibrate stimulated EH activity by 83% and enhanced toxin production
6.3 fold. Both 4-fluorochalcone oxide (4-FCO) and (2S,3S)-(-)-3-(4-nitrophenyl)-glycidol (SS-NPG) inhibited EH activity in
vitro with a IM50f 23 ± 1 μM and 72 ± 19 μM, respectively. The possible physiological substrate 9,10-epoxystearic acid was hydrolyzed more
efficiently by Aal sEH than the model substrates trans- and cis-stilbene oxide (TSO and CSO) and trans- and cis-diphenylpropane
oxide (tDPPO and cDPPO).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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James A. West Abdelaziz Beqqali Zsuzsanna Ament Perry Elliott Yigal M. Pinto Eloisa Arbustini Julian L. Griffin 《Metabolomics : Official journal of the Metabolomic Society》2016,12(3):59
Metabolomics can be performed either as an ‘open profiling’ tool where the aim is to measure, usually in a semi-quantitative manner, as many metabolites as possible or perform ‘closed’ or ‘targeted’ analyses where instead a pre-defined set of metabolites are measured. Targeted methods can be designed to be more sensitive and quantitative and so are particularly appropriate to systems biology for quantitative models of systems or when metabolomics is performed in a hypothesis driven manner to test whether a particular pathway is perturbed. We describe a targeted metabolomics assay that quantifies a broad range of over 130 metabolites relevant to cardiac metabolism including the pathways of the citric acid cycle, fatty acid oxidation, glycolysis, the pentose phosphate pathway, amino acid metabolism, the urea cycle, nucleotides and reactive oxygen species using tandem mass spectrometry to produce quantitative, sensitive and robust data. This assay is illustrated by profiling cardiac metabolism in a lamin A/C (Lmna) mouse model of dilated cardiomyopathy (DCM). The model of DCM was characterised by increases in concentrations of proline and methyl-histidine suggestive of increased myofibrillar and collagen degradation, as well as decreases in a number of citric acid cycle intermediates and carnitine derivatives indicating reduced energy metabolism in the dilated heart. These assays could be used for any other cardiac or cardiovascular disease in that they cover central core metabolism and key pathways involved in cardiac metabolism, and may provide a general start for many mammalian systems. 相似文献