61 resultados para regulating station
Resumo:
The whisker follicle has CD34-positive stem cells that migrate from their niche near the bulge along the glassy membrane to the whisker bulb, where they participate in the formation of the whisker shaft. Using immunohistochemistry we found the glycoprotein tenascin-C in the fibrous capsule of mouse whisker follicles, along the glassy membrane and in the trabecular region surrounding keratin-15-negative, CD34-positive stem cells. The related glycoprotein tenascin-W is found in the CD34-positive stem cell niche, in nearby trabeculae, and along the glassy membrane. Tenascin-W is also found in the neural stem cell niche of nearby hair follicles. The formation of stress fibers and focal adhesion complexes in CD34-positive whisker-derived stem cells cultured on fibronectin was inhibited by both tenascin-C and tenascin-W, which is consistent with a role for these glycoproteins in promoting the migration of these cells from the niche to the whisker bulb. Tenascin-C, but not tenascin-W, increased the proliferation of whisker follicle stem cells in vitro. Thus, the CD34-positive whisker follicle stem cell niche contains both tenascin-C and tenascin-W, and these glycoproteins may play a role in directing the migration and proliferation of these stem cells.
Resumo:
The natural regulation of the water cycle by tropical montane forests is an important ecosystem service. Within this chapter we focus on water balance and regulation of the water cycle. Differences of rainfall-runoff generation across scales change from a near-surface event water driven system in pristine rainforest-covered micro-catchments to a more groundwater pre-event water dominated one on the mesoscale. The highly dynamic discharges are often correlated with total suspended sediment loads. However, we also observed total suspended sediment peaks at times of low flow, indicating a decoupling of erosion and stream transport and a triggering of landslides not directly related to hydrological processes. We also summarize likely future trends of water-related ecosystem services and expect an increase in human use and benefits of fresh water use whereas changes in water regulation and water purification services remain unchanged on a high level.
Resumo:
Long-term measurements of CO2 flux can be obtained using the eddy covariance technique, but these datasets are affected by gaps which hinder the estimation of robust long-term means and annual ecosystem exchanges. We compare results obtained using three gap-fill techniques: multiple regression (MR), multiple imputation (MI), and artificial neural networks (ANNs), applied to a one-year dataset of hourly CO2 flux measurements collected in Lutjewad, over a flat agriculture area near the Wadden Sea dike in the north of the Netherlands. The dataset was separated in two subsets: a learning and a validation set. The performances of gap-filling techniques were analysed by calculating statistical criteria: coefficient of determination (R2), root mean square error (RMSE), mean absolute error (MAE), maximum absolute error (MaxAE), and mean square bias (MSB). The gap-fill accuracy is seasonally dependent, with better results in cold seasons. The highest accuracy is obtained using ANN technique which is also less sensitive to environmental/seasonal conditions. We argue that filling gaps directly on measured CO2 fluxes is more advantageous than the common method of filling gaps on calculated net ecosystem change, because ANN is an empirical method and smaller scatter is expected when gap filling is applied directly to measurements.
Resumo:
The study forest regulates nutrient cycles as a supporting ecosystem service mainly via retention in the biosphere and the soil organic layer. How tight the nutrient cycles are depends on environmental conditions. In this chapter, we focus on the roles of (1) deposition from the atmosphere, (2) soil moisture regime, and (3) conversion to pasture in the nutrient cycle. Between 1998 and 2010, there were a seasonal deposition of salpetric acid, an episodic deposition of Ca and Mg from Sahara dusts, and a continuous increase in reactive N inputs related to Amazonian forest fires, the El Niño Southern Oscillation cycle, and the economic development, respectively. Simultaneously, soils became increasingly drier enhancing nutrient release by mineralization. An increasing number of rain storms could considerably increase the export of N and base metals (K, Ca, Mg) via fast surface-near lateral transport in soil. Land-use change from forest to pasture introduces alkaline ashes and grass-derived organic matter. The resulting increases in soil pH and nutrient and substrate supply increase nutrient cycling rates because of enhanced microbial activity.
Resumo:
Deregulation strategies and their regulating effects: The case of the termination of Social Assistance for rejected asylum seekers in Switzerland. In Switzerland, rejected asylum seekers no longer have any residence rights. In 2003 the Swiss state decided to terminate the so far granted social assistance for people with a non-entry decision on their asylum request. In 2008 the termination of social assistance was expanded to all rejected asylum seekers. Nevertheless, facing the impossibility of deporting them, the Swiss state entitled this group of people to emergency assistance. It is a basic, which is stated in the Swiss Federal constitution. In this context, new structures were established specially for rejected asylum seekers. These structures had to be set up, financed, controlled, managed and legitimized. For example, collective centres were set up exclusively for rejected asylum seekers. In this speech, I want to analyze the political and bureaucratic process of terminating social assistance for rejected asylum seekers. The exclusion of rejected asylum seekers from social aid was embedded in a wider austerity program of the Federal State. The Federal Migration Office had been requested to save money. The main official goal was to reduce the support of these illegalized people, reduce any structures that would prolong their stay on Swiss ground and to set incentives so that they would leave the country on their own. But during the implementation, new regulating effects emerged. Drawing on ethnographic material, I will highlight these “messy procedures” (Sciortino 2004). First, I will analyze the means and goals developed by the Federal authorities while conceptualising the termination of social assistance. Second, I will focus on the new built structures and elaborate the practices and legitimating strategies of the authorities. As a conclusion, I will analyze the ambivalences of these processes which, at the end, established specific structures for the “unwanted”.
Resumo:
Review of 'Regulating Content - The European Regulatory Framework for the Media and Related Creative Sectors', by M. Holoubek, D. Damjanovic, M. Trainer (Alphen aan den Rijn: Kluwer Law International, 2007), including some thoughts on contemporary media regulation.
Resumo:
Digital technologies have profoundly changed not only the ways we create, distribute, access, use and re-use information but also many of the governance structures we had in place. Overall, "older" institutions at all governance levels have grappled and often failed to master the multi-faceted and multi-directional issues of the Internet. Regulatory entrepreneurs have yet to discover and fully mobilize the potential of digital technologies as an influential factor impacting upon the regulability of the environment and as a potential regulatory tool in themselves. At the same time, we have seen a deterioration of some public spaces and lower prioritization of public objectives, when strong private commercial interests are at play, such as most tellingly in the field of copyright. Less tangibly, private ordering has taken hold and captured through contracts spaces, previously regulated by public law. Code embedded in technology often replaces law. Non-state action has in general proliferated and put serious pressure upon conventional state-centered, command-and-control models. Under the conditions of this "messy" governance, the provision of key public goods, such as freedom of information, has been made difficult or is indeed jeopardized.The grand question is how can we navigate this complex multi-actor, multi-issue space and secure the attainment of fundamental public interest objectives. This is also the question that Ian Brown and Chris Marsden seek to answer with their book, Regulating Code, as recently published under the "Information Revolution and Global Politics" series of MIT Press. This book review critically assesses the bold effort by Brown and Marsden.
Resumo:
The Zimmerwald SLR station is operated in a monostatic mode with 532nm laser pulses emitted at adjustable frequencies of 90-110Hz with energies slightly less than 10mJ. A rotating shutter protects the CSPAD receiver from the backscatter of the transmit beam. These systems are located below the telescope in an operator room housed within the observatory building with the laser system located in a separated, air-conditioned part of the room. All hardware components may be automatically accessed by the control software and from remote if required. Thanks to the fully automatic and remotely controllable SLR operations, the Zimmerwald station is one of the most productive stations in the ILRS network. Key characteristics of the hardware are shown. Specialities like the tracking of the full GLONASS constellation, one-way ranging to the Lunar Reconnaissance Orbiter, and photon reception from bi-static experiments with the Graz SLR station are highlighted as well.