2,380 research outputs found
'Vis ruikt nou eenmaal zo'. 'Responsive regulation' bij de Voedsel en Waren Autoriteit
‘Responsive regulation’ is een theorie die sinds enige jaren nationaal en internationaal furore maakt onder zowel beleidsmakers als wetenschappers (zie Van de Bunt e.a., 2007, 390-391). Dit is opmerkelijk omdat de toepasbaarheid van
deze theorie tot voor kort niet of nauwelijks is getoetst (vgl. Nielsen, 2006, 395; Huisman & Beukelman, 2007, 104; maar zie Braithwaite e.a., 1994; Haines, 1997, 218-229), terwijl in beleidskringen de laatste jaren veel nadruk wordt gelegd op
‘evidence-based’ beleid. Pas onlangs zijn enkele studies verschenen waarin responsive regulation kritisch tegen het licht is gehouden (Van de Bunt e.a., 2007; Baldwin & Black, 2008). Onze doelstelling is om de toepasbaarheid van drie fundamentele
veronderstellingen te toetsen die aan de gangbare interpretatie van deze theorie ten grondslag liggen. Dit doen wij aan de hand van een empirisch onderzoek bij de Voedsel en Waren Autoriteit (VWA), omdat die ook responsive regulation tot uitgangspunt van haar optreden heeft verheven (Voedsel en Waren
Autoriteit, 2006). We zetten eerst uiteen wat deze theorie inhoudt en welke veronderstellingen eraan ten grondslag liggen. Na de methodologische paragraaf bespreken wij de bevindingen uit ons veldwerk en gaan wij in op de generaliseerbaarheid
van onze bevindingen
An Alternative Approach to the Calculation and Analysis of Connectivity in the World City Network
Empirical research on world cities often draws on Taylor's (2001) notion of
an 'interlocking network model', in which office networks of globalized service
firms are assumed to shape the spatialities of urban networks. In spite of its
many merits, this approach is limited because the resultant adjacency matrices
are not really fit for network-analytic calculations. We therefore propose a
fresh analytical approach using a primary linkage algorithm that produces a
one-mode directed graph based on Taylor's two-mode city/firm network data. The
procedure has the advantage of creating less dense networks when compared to
the interlocking network model, while nonetheless retaining the network
structure apparent in the initial dataset. We randomize the empirical network
with a bootstrapping simulation approach, and compare the simulated parameters
of this null-model with our empirical network parameter (i.e. betweenness
centrality). We find that our approach produces results that are comparable to
those of the standard interlocking network model. However, because our approach
is based on an actual graph representation and network analysis, we are able to
assess cities' position in the network at large. For instance, we find that
cities such as Tokyo, Sydney, Melbourne, Almaty and Karachi hold more strategic
and valuable positions than suggested in the interlocking networks as they play
a bridging role in connecting cities across regions. In general, we argue that
our graph representation allows for further and deeper analysis of the original
data, further extending world city network research into a theory-based
empirical research approach.Comment: 18 pages, 9 figures, 2 table
The relation between the electron spin polarization of the donor triplet state of the photosynthetic reaction center from Rhodopseudomonas viridis and the redox state of the primary acceptor
AbstractThe hypothesis [(1986) Photobiochem. Photobiophys. 11, 95-100] that the temperature dependence of the electron spin polarization (ESP) pattern of the Δm = ± 1 EPR spectrum of the triplet state PR of the Rhodopseudomonas viridis reaction center is caused by magnetic interaction between the reduced menaquinone-iron complex Q−Fe2+ and the electron spin on I− (reduced bacteriopheophytin b), which is part of the radical pair P+I− (P+ is the oxidized primary electron donor P960) has been investigated. It was found that the AEAEAE ESP pattern of the EPR spectrum detected at T > 20 K changes into the usual AEEAAE pattern, when Q−Fe2+ is photochemically converted into Q2−Fe2+. This demonstrates that the presence of Q− in Q−Fe2+ is a necessary condition to obtain the AEAEAE ESP pattern
Hypertriglyceridemia, Metabolic Syndrome, and Cardiovascular Disease in HIV-Infected Patients: Effects of Antiretroviral Therapy and Adipose Tissue Distribution
The use of combination antiretroviral therapy (CART) in HIV-infected patients has resulted in a dramatic decline in AIDS-related mortality. However, mortality due to non-AIDS conditions, particularly cardiovascular disease (CVD) seems to increase in this population. CART has been associated with several metabolic risk factors, including insulin resistance, low HDL-cholesterol, hypertriglyceridemia and postprandial hyperlipidemia. In addition, HIV itself, as well as specific antiretroviral agents, may further increase cardiovascular risk by interfering with endothelial function. As the HIV population is aging, CVD may become an increasingly growing health problem in the future. Therefore, early diagnosis and treatment of cardiovascular risk factors is warranted in this population. This paper reviews the contribution of both, HIV infection and CART, to insulin resistance, postprandial hyperlipidemia and cardiovascular risk in HIV-infected patients. Strategies to reduce cardiovascular risk are also discussed
The Spatial Cross-Correlation Method for Dispersive Surface Waves
Dispersive surface waves are routinely used to estimate the subsurface shear-wave velocity distribution, at all length scales. In the well-known Spatial Autocorrelation method, dispersion information is gained from the correlation of seismic noise signals recorded on the vertical (or radial) components. We demonstrate practical advantages of including the cross-correlation between radial and vertical components of the wavefield in a spatial cross-correlation method. The addition of cross-correlation information increases the resolution and robustness of the phase velocity dispersion information, as demonstrated in numerical simulations and a near-surface field study with active seismic sources, where our method confirms the presence of a fault-zone conduit in a geothermal field
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