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51.
The similarities and differences in molecular mechanisms regulating invertebrate and mammalian folliculogenesis are starting to be deciphered. In Drosophila, the neoplastic tumor suppressor gene discslarge is crucial for suppressing proliferation and movement of follicle cells relative to the growing oocyte. Lethal giant larvae and scribble play similar roles and have been suggested to collaborate intimately with discslarge. We have identified and determined the expression pattern of murine homologs of these Drosophila genes. In situ data shows that murine discslarge-1, discslarge-3, discslarge-4, lethal giant larvae, and scribble are expressed in both overlapping and distinct patterns in oocytes and granulosa cells in maturing follicles. Disclarge-4 is expressed in the surface epithelium and is lost in mouse carcinogenic surface epithelial cells. All of these genes, as well as discslarge-2 and discslarge-5, are expressed in human ovaries. Our data suggests that as in Drosophila, these tumor suppressors may cooperate during mammalian folliculogenesis, but also have distinct functions.  相似文献   
52.

Purpose

This article is the third of a series of articles presenting the results of research on the implementation of life cycle management tools in small- and medium-sized companies in Poland. The purpose of the three-part series of articles is to present the results of research on the implementation of life cycle tools in Polish small and medium enterprises (SMEs). This work is part of a project financed by the Polish Agency for Enterprise Development (PAED) which began in February 2011. It was carried out by the Wielkopolska Quality Institute—a business environment institution associated with the Polish Centre for LCA (PCLCA). The main practical objective of the project was to support SMEs in their business development, e.g. by expanding their horizons beyond the sphere of their operation and identifying new areas for the improvement and promotion of the products and services on offer. The specific objective of the analysis involving the assessment of life-cycle costs of products and services was an attempt to answer the question to determine whether the assessment carried out in accordance with the life-cycle cost (LCC) methodology is a good tool for cost management in this type of business. Part 3 describes the results of studies on the assessment of the implementation of LCC in SMEs conducted in 50 companies involved in the project.

Methods

In order to assess the effectiveness of the project and the effectiveness of the implementation of LCA and LCC, a survey was conducted of small- and medium-sized businesses where the implementation works had been fully completed. In total, 50 organisations agreed to participate in the LCC survey (while 46 in the LCA—part 2 paper), which was 71 % of all the companies where the LCA and LCC studies had been carried out within the project. The survey was conducted using individual in-depth interviews. Questions to the representatives of the companies referred both to aspects of their operating in the market (characteristics of a company, its market share, management systems, environmental policy, suppliers, clients) and the implementation of their environmental service (assessment of its effectiveness, motivation, difficulties in its implementation), as well as opinions on the potential applications of LCA in their current operations.

Results and discussion

The experience and observations of LCC experts resulting from their cooperation with the analysed organisations are largely supported by the results of the survey. The overall impression gained from the project is that the small- and medium-sized enterprises considered have a problem with accepting and understanding the life-cycle perspective, and show limited interest in taking liability for environmental and cost aspects beyond the mandatory legal standards and boundaries of their business operations. Nevertheless, the LCC analyses aroused much bigger interest among the companies than the environmental due to the fact that the cost aspects in companies undergoing normal development are seen as an important source of information about the structure of the costs generated with respect to the products or services provided. It is important to note that a very important factor encouraging businesses to join the studies was the fact that they were cost-free. Moreover, the planned introduction of a new product onto the market was the argument that often influenced the decision to implement the LCC. The survey has shown that companies rarely perform cost analyses including all stages of the life cycle of a product or service. Although the awareness of the importance of conducting economic researches for the entire life cycle of a product or service is great, it turned out to be problematic to unambiguously define the practical use of such an analysis, at least at the present stage of development of the companies surveyed.

Conclusions

The results obtained in the survey indicate that in the case of simple products, with a short life cycle, complex cost analyses may seem less useful. For more complex products or services, with long periods of use, high reliability required, and high operating costs, the analyses presented are useful tools that increase the economic efficiency of the projects implemented. It appears that from the point of view of polish SMEs, the usefulness of an LCA is seen mainly from the angle of opportunities for cost reduction (preferably in business) and increased sales (marketing). A good solution would be to conduct relatively simple, but integrated LCA/LCC analyses in SMEs so that the companies would clearly see the economic effects of the proposed environmental improvements.  相似文献   
53.

Purpose

This article is the first of a series of articles presenting the results of research on the implementation of life cycle management tools in small- and medium-sized companies in Poland. This work is part of a project financed by the Polish Agency for Enterprise Development (PAED) which began in February 2011. It was carried out by the Wielkopolska Quality Institute—a business environment institution associated with the Polish Centre for Life Cycle Assessment (PCLCA). The main practical objective of the project was to support small and medium enterprises (SMEs) in their business development, e.g. by expanding their horizons beyond the sphere of their operation and identifying new areas for improvement and promotion of the products and services on offer. These publications are a voice in the discussion on the opportunities and pertinence of implementing life cycle thinking (LCT) in small- and medium-sized enterprises and an attempt to identify potential barriers arising from specific characteristics of SMEs which could hinder or even prevent the effective implementation of life cycle techniques. Part 1 presents the situation of SMEs in Poland, general objectives of the project and organisation of the survey process.

Methods

It was decided to carry out research on the effectiveness of the implementation of LCA and life cycle costing (LCC) in organisations that had received financial support for the implementation of life cycle techniques. Financial constraints, which might potentially be a reason for limited interest in LC techniques among SMEs in Poland, were taken into account. Thus, financial support provided an opportunity for the project to obtain information from a wide range of companies, not only from those companies that were particularly aware of the benefits of LC techniques or had a very good financial situation. Research based on the method of individual in-depth interviews was preceded by an analysis of literature showing the status of SMEs in Poland. Given the results, the project objectives were formulated and the ways of conducting the research were defined.

Results and discussion

The comparison of Polish SMEs with the same category of companies in the EU shows some similarities, such as the percentage of companies engaged in various businesses. The differences are expressed primarily in the financial potential, which in the case of Polish SMEs, is significantly smaller than the average in the EU. In the SME sector, there are less than half as many small businesses in Poland than in the EU. There are, however, many more microbusinesses in Poland. An evaluation of the prevalence of LCA and LCC techniques indicates that they are used by just 3 % of Polish SMEs, which is a very small proportion compared to the more than 50 % of SMEs taking any environmental measures. Information collected on specific details of Polish SMEs was used to identify the target group and develop a survey questionnaire which aimed to audit, among other things, the approach to environmental and economic analyses in the past and the approach to the LCA and/or LCC analyses that were implemented from the point of view of difficulties in their implementation and potential use of the results.

Conclusions

Part 1 of the series of articles demonstrates a marginal-scale dissemination of life cycle management techniques among Polish SMEs. Companies definitely prefer to introduce relatively simple solutions that do not require specialised knowledge or unnecessary costs, e.g. they introduce energy-saving bulbs and waste segregation. Only a small percentage of companies implement more complex activities, and most commonly, these are medium-sized companies with greater financial and human capital. So what should be done to make SMEs use life cycle techniques more frequently? Is it appropriate to make changes in the methodology and life cycle techniques as such, or should, rather, the incentive for SMEs to use LCT come from outside as a requirement of public institutions or suppliers in a supply chain? Answers to these questions are provided in the research conclusions presented in parts 2 and 3 of the series of articles.  相似文献   
54.
Sobralia vallecaucana, section Abbreviatae from Valle del Cauca, Colombia, is described and illustrated on the basis of morphological and molecular study. The analyses of the ITS and matK reveal close relationship between the new species and Sobralia klotzscheana. However, S. vallecaucana can be easily distinguished by its large leaves compared to its very short stem, leaves and leaves’ sheaths strongly hispid underside and lip with two basal ridges and without thickening along its central nerves.  相似文献   
55.
In this study, denitrification of ammonium-reach anaerobic sludge digester liquor was investigated during start-up periods of two laboratory-scale “fill-and-draw” reactors. One reactor was fed with a single carbon source (ethanol), whereas the other reactor was fed with a complex carbon source (fusel oil). During two acclimation experiments, the structure of microbial community involved in denitrification was analyzed using 16S rDNA polymerase chain reaction-denaturing gradient gel electrophoresis fingerprints and fluorescent in situ hybridization. The characteristics of the mixed liquor were additionally supported by regular measurements of nitrate uptake rates. The addition of fusel oil and ethanol resulted in a significant enhancement of the denitrification rate and efficiency combined with the increasing volumetric addition of sludge digester liquor up to 15 % of the reactor volume. The microbiological analyses revealed that the addition of sludge digester liquor as well as both external carbon sources (fusel oil and ethanol) did not affect the structure of microbial communities in a severe way. In both reactors, Curvibacter sp. and Azoarcus sp. were found as the most abundant representatives of denitrifiers.  相似文献   
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The Cerebral Circle Region, also known as the Circle of Willis (CoW), is a loop of arteries that form arterial connections between supply arteries to distribute blood throughout the cerebral mass. Among the population, only 25% to 50% have a complete system of arteries forming the CoW. 3D time-varying simulations for three different patient-specific artery anatomies of CoW were performed in order to gain a better insight into the phenomena existing in the cerebral blood flow. The models reconstructed on the basis of computer tomography images start from the aorta and include the largest arteries that supply the CoW and the arteries of CoW. Velocity values measured during the ultrasound examination have been compared with the results of simulations. It is shown that the flow in the right anterior artery in some cases may be supplied from the left internal carotid artery via the anterior communicating artery. The investigations conducted show that the computational fluid dynamic tool, which provides high resolution in both time and space domains, can be used to support physicians in diagnosing patients of different ages and various anatomical arterial structures.  相似文献   
59.
The ADAM and ADAMTS families, also called adamalysins belong to an important group of extracellular matrix proteins. The ADAMs family belong to both the transmembrane and secreted proteins, while ADAMTS family only contains secreted forms. Adamalysins play an important role in the cell phenotype regulation via their activities in signaling pathways, cell adhesion and migration. The human proteome contains 21 ADAM, and 19 ADAMTS proteins, which are involved in extracellular matrix remodeling, shedding of various substrates such as: adhesion ligands, growth factors, their receptors and diverse cytokines. Recent studies provide evidence that adamalysins play a crucial role in colorectal cancer (CRC) etiopathogenesis. It seems possible that adamalysins might be used as CRC prediction markers or potential pharmaceutical targets. [BMB Reports 2013; 46(3): 139-150]  相似文献   
60.
Biological invasions are projected to be the main driver of biodiversity and ecosystem function loss in lakes in the 21st century. However, the extent of these future losses is difficult to quantify because most invasions are recent and confounded by other stressors. In this study, we quantified the outcome of a century‐old invasion, the introduction of common carp to North America, to illustrate potential consequences of introducing non‐native ecosystem engineers to lakes worldwide. We used the decline in aquatic plant richness and cover as an index of ecological impact across three ecoregions: Great Plains, Eastern Temperate Forests and Northern Forests. Using whole‐lake manipulations, we demonstrated that both submersed plant cover and richness declined exponentially as carp biomass increased such that plant cover was reduced to <10% and species richness was halved in lakes in which carp biomass exceeded 190 kg ha?1. Using catch rates amassed from 2000+ lakes, we showed that carp exceeded this biomass level in 70.6% of Great Plains lakes and 23.3% of Eastern Temperate Forests lakes, but 0% of Northern Forests lakes. Using model selection analysis, we showed that carp was a key driver of plant species richness along with Secchi depth, lake area and human development of lake watersheds. Model parameters showed that carp reduced species richness to a similar degree across lakes of various Secchi depths and surface areas. In regions dominated by carp (e.g., Great Plains), carp had a stronger impact on plant richness than human watershed development. Overall, our analysis shows that the introduction of common carp played a key role in driving a severe reduction in plant cover and richness in a majority of Great Plains lakes and a large portion of Eastern Temperate Forests lakes in North America.  相似文献   
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