Heterogeneity between centers in multicenter trials with time to event outcome can be modeled by the frailty proportional hazards model. The majority of the different approaches that have been used to fit frailty models assume either the gamma or the lognormal frailty density and are based on sim...
Duchateau, L.
,
Janssen, P.
,
Lindsey, P.
,
Legrand, C.
,
Nguti, R.
,
Sylvester-Bradley, Rosemary
,
[The shared frailty model and the power for heterogeneity tests in multicenter trials]
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The shared frailty model and the power for heterogeneity tests in multicenter trials
To evaluate vaccinia virus as a delivery system for recombinant antigen in cattle, calves were immunized with a recombinant vaccinia virus (rVV) expressing the sporozoite surface antigen (p67) of Theileria parva (V-67) combined with those expressing bovine IL-4 (V-IL4) or IL-2 (V-IL2). The anti-p...
Honda, Y.
,
Waithaka, M.M.
,
Taracha, E.L.N.
,
Duchateau, L.
,
Musoke, A.J.
,
McKeever, Declan J.
,
[Delivery of the Theileria parva p67 antigen to cattle using recombinant vaccinia virus: IL-2 enhances protection]
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Delivery of the Theileria parva p67 antigen to cattle using recombinant vaccinia virus: IL-2 enhances protection
Cattle immunised with a recombinant form of p67, the major surface antigen of Theilleria parva sporozoites, have been shown to be protected against parasite challenge. In an attempt to simplify the immunisation procedure live attenuated Salmonella strains expressing p67 have been constructed and ...
Heussler, V.T.
,
Taracha, E.L.N.
,
Musoke, A.J.
,
Duchateau, L.
,
McKeever, Declan J.
,
[Immunisation with live attenuated Salmonella dublin expressing a sporozoite protein confers partial protection against Theileria parva]
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Immunisation with live attenuated Salmonella dublin expressing a sporozoite protein confers partial protection against Theileria parva
The classical Leslie matrix methodology is extended to describe the life cycle of the brown ear tick (R. appendiculatus), incorporating both within and between stage transitions of the population. We use data from the highveld of Zimbabwe Reported in Short et al. (1989a,b). The model incorporates...
Mwambi, H.G.
,
Odhiambo, J.W.
,
Duchateau, L.
,
[A multiple matrix model to study the population dynamics of R. appendiculatus in Zimbabwe]
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A multiple matrix model to study the population dynamics of R. appendiculatus in Zimbabwe
Multivariate logistic regression models are mostly used to identify risk factors associated withthe occurrence of particular disease processes. Logistic regression models have also been used as tools for veterinary diagnosis by providing the probability of a particular disease in an individual an...
Pfeiffer, Dirk U.
,
Duchateau, L.
,
Kruska, R.L.
,
Ushewokunze-Obatolu, U.
,
Perry, Brian D.
,
[A spatially predictive logistic regression model for occurrence of theileriosis outbreaks in Zimbabwe]
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A spatially predictive logistic regression model for occurrence of theileriosis outbreaks in Zimbabwe
Duchateau, L.
,
Jansen, P.
,
Rowlands, G.J.
,
[Linear mixed model: An introduction with applications in veterinary research]
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Linear mixed model: An introduction with applications in veterinary research
Large databases with multiple variables, selected because they are available and might provide an insight into establishing causal relationships, are often difficult to analyse and interpret because of multicollinearity. The objective of this study was to reduce the dimensionality of a multivaria...
Duchateau, L.
,
Kruska, R.L.
,
Perry, Brian D.
,
[Reducing a spatial database to its effective dimensionality for logistic - regression analysis of incidence of livestock disease]
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Reducing a spatial database to its effective dimensionality for logistic - regression analysis of incidence of livestock disease
Mixed models have important advantages as compared to fixed effects models. Complex data structures can be described in a natural way in mixed models. The analysis of unbalanced data is a straightforward extension of the analysis of balanced data in the mixed model framework. Furthermore, the app...
Duchateau, L.
,
[Comparing the mixed model and the fixed effects model: Do the advantages justify the costs?]
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Comparing the mixed model and the fixed effects model: Do the advantages justify the costs?
In tropical cropping systems with few external imputs, efficient management of mineral N derived from added organic residues is essential for the proper functioning of the system. We studied the dynamics of mineral Nitroden (N) in the top 100 cm of soil with a system tensiometers and suction cups...
Vanlauwe, Bernard
,
Diels, J.
,
Duchateau, L.
,
Sanginga, N.
,
Merckx, R.
,
[Mineral N dynamics in bare and cropped Leucaena leucocephala and Dactyladenia barteri alley cropping systems after the addition of 15Nlabelled leaf residues]
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Mineral N dynamics in bare and cropped Leucaena leucocephala and Dactyladenia barteri alley cropping systems after the addition of 15Nlabelled leaf residues