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Aspinall  Richard  Staiano  Michele 《Landscape Ecology》2019,34(7):1503-1524
Context

We address understanding of whole-system and landscape-based approaches to the ecosystem services framework by considering the supply of provisioning services and the dynamics of agricultural land use in Scotland between 1940 and 2016.

Objectives

To characterise and understand the dynamics of change in provisioning services from agriculture in Scotland over the period 1940–2016. To identify ways in which funds of capitals and flows of inputs and output ecosystem goods are linked to land management practices and policies at a national scale.

Methods

Data describing agricultural land use, production, financial and energy inputs and outputs, and drivers of change in land use in Scotland are analysed with an accounting framework that links funds of natural, human, physical and financial capital, with flows of goods and services. Flow–fund ratios are used as benchmarks of system performance and dynamics.

Results

Scotland’s agriculture has modernised since 1940 and become more efficient in conversion of resources, with a consequent increase in delivery of provisioning goods and services. Although the energy ratio, and flow of goods per unit hectare and per unit labour have increased, the inputs necessary to maintain those flows of ecosystem goods are also increasing, even as their relative economic costs decrease. Increases in use of fertiliser suggests that production from the soil, as a natural capital fund, is not being conserved without a large, and increasing, input. Analysis of the complexity of the coupled agricultural land system also suggests that land management rather than biodiversity is a necessary subject for evaluation of provisioning services from agriculture. Understanding of ecosystem services based on accounts that integrate inputs, outputs and flows from funds of natural, human, social, financial and physical capitals, provides a process-based foundation for improved understanding of ecosystem services and human–environmental relationships.

Conclusions

Adopting an accounting approach for understanding the role of agricultural land use for supply of provisioning services, and particularly examining a long time-series of accounts, enables understanding of land changes and underlying drivers, as well as the contribution of cultural and other aspects of human systems coupled with environment systems. Accounting for ecosystem services using costs as well as benefits, and use of metrics beyond financial benefit, supports debate and evaluation of trade-offs between services and has direct relevance for decision- and policy-making.

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Connexin (Cx) channels are sites of cytoplasmic communication between contacting cells. Evidence indicates that the opening of hemichannels occurs under both physiological and pathological conditions. In this paper, the involvement of Cx-43 hemichannels is demonstrated in the pathogenesis of Yersinia. Parental HeLa cells and transfected HeLa cells stably expressing Cx-43 (HCx43) were infected with Yersiniaenterocolitica, and bacterial uptake was measured by the colony-forming unit method. Bacterial uptake was higher in HCx43 cells than in parental cells and was inhibited by the Cx channel blocker, 18-alpha-glycyrrhetinic acid (AGA). The inhibitory effect of AGA was more pronounced on the Y. enterocolitica uptake by HCx43 cells than by parental cells. The ability of HCx43 cells to incorporate the permeable fluorescent tracer Lucifer Yellow (LY) was assessed. Dye incorporation was inhibited by AGA, whereas Y. enterocolitica infection of HCx43 cells increased LY incorporation. Western blotting analysis demonstrated that Y. enterocolitica infection of HCx43 cells induced tyrosine phosphorylation of Cx-43, thus supporting a critical role for Cx-43 in the strategies exploited by bacterial pathogens to invade non-phagocytic cells.  相似文献   
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Paxillin and p130CAS are two adaptor proteins localized at the focal adhesions which play an important role in cell signaling, cell motility and oncogenic transformation. In this study we evaluated the levels of paxillin and p130CAS in feline and canine mammary tumor tissues at different stages of malignancy. The results obtained by Western blotting analysis showed no significant differences in the amounts of paxillin and p130CAS between normal and non-invasive tumor tissues. By contrast, mammary tumor tissues with the invasive phenotype showed lower levels of paxillin P < 0.01 and higher levels of p130CAS P < 0.001 than normal tissues. The decrease P < 0.001 of the amount of paxillin and the increase P < 0.001 of p130CAS levels were correlated with the progression stage of malignancy. Since paxillin and p130CAS are involved in regulating cell migration, our results suggest that low levels of paxillin together with high levels of p130CAS expression may cause certain breast cancers to be more motile and possibly more aggressive. Thus, both paxillin and p130CAS may represent useful prognosticators of feline and canine breast cancer malignancy.  相似文献   
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Integrins are heterodimeric receptors that mediate important cell functions, including cell adhesion, migration and tissue organisation. These transmembrane receptors regulate the direct association of cells with each other and with extracellular matrix proteins. However, by binding their ligands, integrins provide a transmembrane link for the bidirectional transmission of mechanical forces and biochemical signals across the plasma membrane. Interestingly, several of this family of receptors are exploited by pathogens to establish contact with the host cells. Hence, microbes subvert normal eukaryotic cell processes to create a specialised niche which allows their survival. This review highlights the fundamental role of integrins in bacterial pathogenesis.  相似文献   
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In this study, different types of tissue sampling for PCR-based diagnosis and follow-up of canine visceral leishmaniosis were compared. Skin, whole blood and lymph node samples were collected from 95 naturally infected dogs living in South Italy, where the disease is endemic. Twenty-nine of these 95 dogs, treated with meglumine administered concurrently with allopurinol for 30 days, and then with allopurinol alone, were monitored during a period of 2 years. The DNA extracted from the clinical specimens was amplified by PCR using as target DNA a 116-bp fragment in the constant region of the kinetoplast DNA minicircle. PCR analysis was more sensitive than indirect immunofluorescence antibody test in detecting Leishmania infection in symptomatic dogs: 99% of lymph node samples resulted positive, whereas 94% of blood samples and 95% of skin samples gave a positive result. PCR analysis of samples from dogs followed up 2 years showed that: (1) all subjects resulted positive in at least one of the three types of samples; (2) all time the dogs had a relapse, PCR resulted positive in all three types of samples; (3) when dogs were apparently healthy, PCR analysis was positive on skin and lymph node samples, but not always on blood samples. Since lymph node sampling is invasive and sometimes difficult in healthy asymptomatic dogs, our results suggest that, independently from the presence or not of cutaneous lesions, skin biopsy represents a good substratum for PCR-based diagnosis and follow-up of canine visceral leishmaniosis.  相似文献   
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Accumulation of rare earth elements (REE) in the soil may be due to the use of REE enriched fertilizers and to contamination by REE containing wastes. Although widely used in China for soil and foliar dressing of crops, little is known about the effect of REE applications on the soil microbial community. The effect of REE on the growth of biological control strains of Trichoderma atroviride and Trichoderma harzianum was investigated in vitro using either a mix of different REE containing different amounts of lanthanum, cerium, praseodymium, neodymium, gadolinium nitrate and lanthanum nitrate alone in comparison to treatments with potassium nitrate and water. In plate tests applied concentrations ranged from 0.1 mM to 300 mM for lanthanum and REE mix and from 0.1 mM to 900 mM for the potassium solution. In liquid culture tests applied concentrations ranged from 0.001 mM to 100 mM for lanthanum and REE mix and from 0.003 mM to 900 mM for the potassium solution. ICP-MS, TEM and TEM X-ray microanalysis were used to study the accumulation of REE in fungal biomass. All the Trichoderma strains showed a good tolerance to the presence of REE in the culture media. Some growth enhancing effects were observed in liquid cultures of T. harzianum strains but not in T. atroviride. Accumulation of REE in fungal biomass, both at intracellular level and in the extracellular matrix, was observed.  相似文献   
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