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In this thesis we study adaptive methods of estimation for two particular
types of statistical problems: regression and density estimation. For all
these problems the classes of probabilities are parameterized by real-valued
functions. In each model, the underlying function is assumed to belong to
some class of smooth functions. In practice the `true' smoothness of the
function is unknown and so the actual class is also unknown.
We study different regression problems with fixed discrete designs:
regression on the real line and regression on a bounded
interval. Formally, the distinction here lies just in the definition of the
underlying functional classes. The construction of optimal adaptive
procedures however is quite different in these cases. This is underlined by
the essential difference between these two models; namely...
Met de transitie van de jeugdzorg naar de gemeente sinds 1 januari 2015, zijn er in Utrecht en verschillende andere gemeenten generalistische wijkteams voor jeugd en gezin geïntroduceerd. Naast deze situationele verandering in het stelsel wordt er ook een transformatie beoogd. Een onderdeel van deze transformatie is de beweging om opvoed- en ontwikkelingsproblemen van kinderen en gezinnen te normaliseren. Met deze studie is getracht na te gaan hoe het normaliseren in de generalistische wijkteams wordt belichaamd. Hiervoor zijn in het voorjaar van 2015, 14 interviews afgenomen bij medewerkers van de wijkteamorganisatie van jeugd en gezin in Utrecht. Daarnaast zijn er 3 observaties gedaan tijdens casuïstiekbesprekingen van 3 teams. De data werd gecodeerd en geanalyseerd. Wat bleek was dat wijkteammedewerkers het normaliseren op verschill...
Cytokines mediate the transduction of proliferative, differentiation and survival signals in the hematopoietic system. Although
the cytokine family is large and diverse, many different cytokines display broadly overlapping functions. This can be explained by the fact that cytokine receptors often share multiple subunits. Specificity in signal transduction can however be achieved through several mechanisms. This review focuses on how signal specificity can be achieved within the IL-3, IL-5 and GM-CSF receptor family. This is discussed in terms of receptor expression, recent advances in our understanding of intracellular signalling components, and analysis of null mutant knock-out mice.
The spectroscopic properties and catalytic behavior of Cu(AA)n m+ complexes (AA ) amino acid (glycine,
lysine, histidine, alanine, serine, proline, tyrosine, phenylalanine, glutamine, glutamic acid, cysteine, tryptophan,
leucine, and arginine)) in faujasite-type zeolites have been investigated. Successful immobilization was
achieved by a simple cation exchange procedure with aqueous solutions of preformed Cu(AA)n m+ complexes.
The best ion exchange results were obtained with lysine, arginine, proline (at pH ) 10), and histidine (at pH
= 7.3) as ligands and with a AA:Cu 2+ ratio of 5. The internal surface and pore volume are drastically
reduced by the uptake of the Cu(AA)n m+ complexes, and no precipitation of Cu(AA)n m+ crystals was observed
by scanning electron microscopy. Both observations suggest the location of the complexes...
The depletion-induced phase separation in a mixture of colloidal particles (PMMA-latex) and nonadsorbing
polymers [poly(styrene)] in a solvent (mixture of tetralin, cis-decalin, and carbon tetrachloride) was investigated
in real space with confocal scanning laser microscopy in the initial, intermediate, and final stage. It was
found that the kinetics and the morphology of the phase separation strongly depend on the polymer concentration,
and thus on the strength of the depletion-induced attraction between the colloidal particles. At moderate
polymer concentrations, crystallization of the PMMA particles is enhanced. At higher polymer concentrations,
only aggregation is observed, resulting in amorphous sediments. The aggregation is diffusion-limited or
reaction-limited, depending on the polymer concentration. Digital image process...
Let A = (aij) andB = (bij) be matrices of the same size. Then their Hadamard product (also
called Schur product) A B is dened by entrywise multiplication: A B = (aij bij) . The Hadamard
unit matrix is the matrix U all of whose entries are 1 (the size of U being understood). A matrix A is Hadamard invertible if all its entries are non-zero, and A (= (a ij is then called the Hadamard inverse of A. IfB is Hadamard invertible, then the Hadamard quotient A =B of A and B is (aijb ij The k-fold Hadamard product A k of A with itself (k 0) is called the k-th Hadamard power of A; thus (aij) k = (a k ij ). In particular, A 0 = U (conventionally we set 0 0 = 1). If A is Hadamard invertible, then A k can be dened for negative integers as well, in an obvious manner. For more information on the Hadamard product, see [7, Chapter 5] and [5].
Foraminifera are unicellular organisms that are abundantly present in the marine realm. They inhabit both the water column as well as the sediment; these latter (benthic) foraminifera are the main subject of this thesis research. They have a high fossilisation potential, and for that reason they have become valuable proxies in paleoecological studies. In modern sediments their role in the ecosystem is considerable. This has been ignored for a long time and it is only since the last few decades that living foraminifera have attracted interest. Predominant regulating factors of benthic foraminiferal occurrence and microhabitat selection are oxygen and organic flux. The relationship between these two factors and microhabitat selection has been described in the TROX model (Jorissen et al., 1995). An amended version of the model (TROX-II; V...
Eosinophil-derived neurotoxin (EDN) found in the granules
of human eosinophils is a cationic ribonuclease toxin. Expression
of the EDN gene (RNS2) in eosinophils is dependent on
proximal promoter sequences in combination with an enhancer
located in the first intron. We further define here the
active region of the intron using transfections in differentiated
eosinophilic HL60 cells. We show that a region containing
a tandem PU.I binding site is important for intronic
enhancer activity. This region binds multiple forms of transcription
factor PU.I as judged by gel-shift analysis and DNA
affinity precipitation. Importantly, introducing point mutations
in the PU.I site drastically reduces the intronic enhancer
activity, showing the importance of PU.I for expression
of EDN in cells of the eosinophilic lineage.
Assaying activation of signal transduction is laborious and does
not allow the study of large numbers of samples, essential for
high-throughput drug screens or for large groups of patients.
Using phosphospecific antibodies, we have developed ELISA
techniques enabling non-radioactive semi-quantitative assess-
ment of the activation state of p42/p44 mitogen-activated protein
kinase (MAPK), p38 MAPK, protein kinase B and the tran-
scription factor cAMP-response-element-binding protein
(CREB) in 96-well plates. This assay has been termed PACE
(phosphospecific antibody cell-based ELISA) and was used
successfully for both adherent and suspension cells. Various
stimuli induced dose-dependent enzymic activity of which the
kinetics closely correlated with those measured via classical
methodology. Using PACE we have now characterize...
We consider the effect of interactions on the line shape of the two-photon 1s-2s transition in a (doubly) spin-polarized atomic hydrogen gas in terms of the interatomic interaction potentials. We show that the frequency-weigted pseudopotentials that describe the interactions between low-energy atoms. The origin of the departures from the simple pseudopotential result for the frequency-weigted sum rule is traced to what we refer to as incoherent contributions to the special weight. These arise from more complicated final states of the many-body system than the ones usually considered. In particular, we show how the relevant response function may be treated in a manner similar to the density-density response function for Fermi liquids, and express it as a coherent part comming from single particle-hole pairs, and an incoherent part commi...
