Jeroen van Herwijnen - Academia.edu (original) (raw)

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Papers by Jeroen van Herwijnen

Physics Letters B, 2010

Decays of b hadrons into final states containing a D 0 meson and a muon are used to measure the b... more Decays of b hadrons into final states containing a D 0 meson and a muon are used to measure the bb production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV at the LHC. In the pseudorapidity interval 2 < η < 6 and integrated over all transverse momenta we find that the average cross-section to produce b-flavoured or b-flavoured hadrons is (75.3±5.4±13.0) µb.

Many resource allocation issues, such as land use- or irrigation planning, require input from ext... more Many resource allocation issues, such as land use- or irrigation planning, require input from extensive spatial databases and involve complex decision-making problems. Recent developments in this field focus on the design of allocation plans that utilize mathematical optimization techniques. These techniques, often referred to as multi criteria decision-making (MCDM) techniques, run into numerical problems when faced with the high dimensionality encountered in spatial applications. In this paper, it is demonstrated how both Simulated annealing, a heuristic algorithm, and Goal Programming techniques can be used to solve high-dimensional optimization problems for multi-site land use allocation (MLUA) problems. The optimization models both minimize development costs and maximize spatial compactness of the allocated land use. The method is applied to a case study in The Netherlands.

Toxicological Sciences, 2010

The embryonic stem cell test (EST) has been designed to predict developmental toxicity based upon... more The embryonic stem cell test (EST) has been designed to predict developmental toxicity based upon compound-induced inhibition of embryonic stem cell (ESC) differentiation. The end point scoring, the test duration, and the definition of the predictivity and the applicability domain require improvements to facilitate implementation of the EST into regulatory testing strategies. The use of transcriptomics to study compound-induced differentiation modulation may improve the EST in each of these aspects. ESC differentiation was induced, and cell samples were collected after 0, 24, and 48 h of differentiation. Additionally, samples were collected that were 24 h exposed to one of five developmentally toxic compounds or a nondevelopmentally toxic compound. All samples were hybridized to Affymetrix GeneChips, and analyses revealed that 26 genes were significantly regulated both during ESC differentiation and by exposure to each of the developmentally toxic compounds tested. Using principal component analysis, we defined a ''differentiation track'' on the basis of this gene list, which represents ESC differentiation. We showed that significant deviation from the differentiation track was in line with the developmental toxic properties of the compounds. The significance of deviation was analyzed using the leave-one-out cross-validation, which showed a favorable prediction of toxicity in the system. Our findings show that gene expression signatures can be used to identify developmental toxicant-induced differentiation modulation. In addition, studying compound-induced effects at an early stage of differentiation combined with transcriptomics leads to increased objectivity in determining differentiation inhibition and to a reduction of the test duration. Furthermore, this approach may improve the predictivity and applicability domain of the EST. Downloaded from 132 VAN DARTEL ET AL. by guest on July 29, 2016 http://toxsci.oxfordjournals.org/ Downloaded from 134 VAN DARTEL ET AL. by guest on July 29, 2016 http://toxsci.oxfordjournals.org/ Downloaded from FIG. 4. (A) Clustering of the 26 genes that are both transcriptionally responsive to ESC differentiation with time and are also regulated by exposure to all developmental toxic compounds tested. (B) PCA of the nonexposed cultures (CON) (individual samples, circles) at different stages of differentiation and compound-exposed cultures (mean of n ¼ 8 samples, crossed squares) using the 26 biomarker genes.

Wetlands provide many important goods and services to human societies, and generate nonuse values... more Wetlands provide many important goods and services to human societies, and generate nonuse values as well. Wetlands are also very sensitive ecosystems that are subject to much stress from human activities. Reducing the stress on wetlands requires a spatial matching between physical planning, hydrological and ecological processes, and economic activities. Spatially integrated modelling and evaluation can support this. The present study has developed a triple layer model that integrates information and concepts from social and natural sciences to address the analysis and evaluation of land-use scenarios for a wetlands area in the Netherlands, the Vecht area. This is the floodplain of river Vecht, located in the centre of the Netherlands. The study has resulted in a set of linked spatial hydrological, ecological and economic models, formulated at the level of grids and polders. The main activities incorporated in the system of models are housing, infrastructure, agriculture, recreation and nature conservation. The formulation of alternative development scenarios is dominated by land use and land cover options that are consistent with the stimulation of agriculture, nature or recreation. Two aggregate performance indicators have been constructed from model output, namely net present value of changes and environmental quality. The spatial characteristics of these indicators are retained in a spatial evaluation that ranks scenarios.

Environmental Modeling & Assessment, 2001

Wetlands provide many important goods and services to human societies, and generate nonuse values... more Wetlands provide many important goods and services to human societies, and generate nonuse values as well. Wetlands are also very sensitive ecosystems that are subject to much stress from human activities. Reducing the stress on wetlands requires a spatial matching between physical planning, hydrological and ecological processes, and economic activities. Spatially integrated modelling and evaluation can support this. The present study has developed a triple layer model that integrates information and concepts from social and natural sciences to address the analysis and evaluation of land-use scenarios for a wetlands area in the Netherlands, the Vecht area. This is the floodplain of river Vecht, located in the centre of the Netherlands. The study has resulted in a set of linked spatial hydrological, ecological and economic models, formulated at the level of grids and polders. The main activities incorporated in the system of models are housing, infrastructure, agriculture, recreation and nature conservation. The formulation of alternative development scenarios is dominated by land use and land cover options that are consistent with the stimulation of agriculture, nature or recreation. Two aggregate performance indicators have been constructed from model output, namely net present value of changes and environmental quality. The spatial characteristics of these indicators are retained in a spatial evaluation that ranks scenarios.

Physics Letters B, 2010

Decays of b hadrons into final states containing a D 0 meson and a muon are used to measure the b... more Decays of b hadrons into final states containing a D 0 meson and a muon are used to measure the bb production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV at the LHC. In the pseudorapidity interval 2 < η < 6 and integrated over all transverse momenta we find that the average cross-section to produce b-flavoured or b-flavoured hadrons is (75.3±5.4±13.0) µb.

Many resource allocation issues, such as land use- or irrigation planning, require input from ext... more Many resource allocation issues, such as land use- or irrigation planning, require input from extensive spatial databases and involve complex decision-making problems. Recent developments in this field focus on the design of allocation plans that utilize mathematical optimization techniques. These techniques, often referred to as multi criteria decision-making (MCDM) techniques, run into numerical problems when faced with the high dimensionality encountered in spatial applications. In this paper, it is demonstrated how both Simulated annealing, a heuristic algorithm, and Goal Programming techniques can be used to solve high-dimensional optimization problems for multi-site land use allocation (MLUA) problems. The optimization models both minimize development costs and maximize spatial compactness of the allocated land use. The method is applied to a case study in The Netherlands.

Toxicological Sciences, 2010

The embryonic stem cell test (EST) has been designed to predict developmental toxicity based upon... more The embryonic stem cell test (EST) has been designed to predict developmental toxicity based upon compound-induced inhibition of embryonic stem cell (ESC) differentiation. The end point scoring, the test duration, and the definition of the predictivity and the applicability domain require improvements to facilitate implementation of the EST into regulatory testing strategies. The use of transcriptomics to study compound-induced differentiation modulation may improve the EST in each of these aspects. ESC differentiation was induced, and cell samples were collected after 0, 24, and 48 h of differentiation. Additionally, samples were collected that were 24 h exposed to one of five developmentally toxic compounds or a nondevelopmentally toxic compound. All samples were hybridized to Affymetrix GeneChips, and analyses revealed that 26 genes were significantly regulated both during ESC differentiation and by exposure to each of the developmentally toxic compounds tested. Using principal component analysis, we defined a ''differentiation track'' on the basis of this gene list, which represents ESC differentiation. We showed that significant deviation from the differentiation track was in line with the developmental toxic properties of the compounds. The significance of deviation was analyzed using the leave-one-out cross-validation, which showed a favorable prediction of toxicity in the system. Our findings show that gene expression signatures can be used to identify developmental toxicant-induced differentiation modulation. In addition, studying compound-induced effects at an early stage of differentiation combined with transcriptomics leads to increased objectivity in determining differentiation inhibition and to a reduction of the test duration. Furthermore, this approach may improve the predictivity and applicability domain of the EST. Downloaded from 132 VAN DARTEL ET AL. by guest on July 29, 2016 http://toxsci.oxfordjournals.org/ Downloaded from 134 VAN DARTEL ET AL. by guest on July 29, 2016 http://toxsci.oxfordjournals.org/ Downloaded from FIG. 4. (A) Clustering of the 26 genes that are both transcriptionally responsive to ESC differentiation with time and are also regulated by exposure to all developmental toxic compounds tested. (B) PCA of the nonexposed cultures (CON) (individual samples, circles) at different stages of differentiation and compound-exposed cultures (mean of n ¼ 8 samples, crossed squares) using the 26 biomarker genes.

Wetlands provide many important goods and services to human societies, and generate nonuse values... more Wetlands provide many important goods and services to human societies, and generate nonuse values as well. Wetlands are also very sensitive ecosystems that are subject to much stress from human activities. Reducing the stress on wetlands requires a spatial matching between physical planning, hydrological and ecological processes, and economic activities. Spatially integrated modelling and evaluation can support this. The present study has developed a triple layer model that integrates information and concepts from social and natural sciences to address the analysis and evaluation of land-use scenarios for a wetlands area in the Netherlands, the Vecht area. This is the floodplain of river Vecht, located in the centre of the Netherlands. The study has resulted in a set of linked spatial hydrological, ecological and economic models, formulated at the level of grids and polders. The main activities incorporated in the system of models are housing, infrastructure, agriculture, recreation and nature conservation. The formulation of alternative development scenarios is dominated by land use and land cover options that are consistent with the stimulation of agriculture, nature or recreation. Two aggregate performance indicators have been constructed from model output, namely net present value of changes and environmental quality. The spatial characteristics of these indicators are retained in a spatial evaluation that ranks scenarios.

Environmental Modeling & Assessment, 2001

Wetlands provide many important goods and services to human societies, and generate nonuse values... more Wetlands provide many important goods and services to human societies, and generate nonuse values as well. Wetlands are also very sensitive ecosystems that are subject to much stress from human activities. Reducing the stress on wetlands requires a spatial matching between physical planning, hydrological and ecological processes, and economic activities. Spatially integrated modelling and evaluation can support this. The present study has developed a triple layer model that integrates information and concepts from social and natural sciences to address the analysis and evaluation of land-use scenarios for a wetlands area in the Netherlands, the Vecht area. This is the floodplain of river Vecht, located in the centre of the Netherlands. The study has resulted in a set of linked spatial hydrological, ecological and economic models, formulated at the level of grids and polders. The main activities incorporated in the system of models are housing, infrastructure, agriculture, recreation and nature conservation. The formulation of alternative development scenarios is dominated by land use and land cover options that are consistent with the stimulation of agriculture, nature or recreation. Two aggregate performance indicators have been constructed from model output, namely net present value of changes and environmental quality. The spatial characteristics of these indicators are retained in a spatial evaluation that ranks scenarios.