S. Lopez

GRB 080503: Implications of a Naked Short Gamma-Ray Burst Dominated by Extended Emission (2008)

Perley, D. A., Metzger, B. D., Granot, J., Butler, N. R., Sakamoto, T., Ramirez-Ruiz, E., ...

We report on observations of GRB 080503, a short gamma-ray burst with very bright extended emission (about 30 times the gamma-ray fluence of the initial spike) in conjunction with a thorough...

High-Redshift Starbursting Dwarf Galaxies Revealed by GRB Afterglows (2008)

Chen, Hsiao-Wen, Perley, Daniel A., Pollack, Lindsey K., Prochaska, J. X., Bloom, J. S., Dessauges-Zavadsky, M., ...

We present a study of 15 long-duration gamma-ray burst (GRB) host galaxies at z>2. The GRBs are selected with available early-time afterglow spectra in order to compare interstellar medium (ISM)...

Modelling the implications of feeding strategy on rumen fermentation and functioning of the rumen wall (2008)

Bannink, A., France, J., Lopez, S., Gerrits, W.J.J., Kebreab, E., Dijkstra, J.

The present study gives a critique of the mechanisms involved with the formation of volatile fatty acid (VFA) formed in the lumen of the reticulo-rumen, the absorption of VFA across the...

Comparison of energy evaluation systems and a mechanistic model for milk production by dairy cattle offered fresh grass-based diets. (2008)

Dijkstra, J., Kebreab, E., Bannink, A., Crompton, L.A., Lopez, S., Abrahamase, P., ...

Grass-based diets are of increasing social-economic importance in dairy cattle farming, but their low supply of glucogenic nutrients may limit the production of milk. Current evaluation systems that...

Alternative regression approaches when modelling energy components (2007)

Dhanoa, M.S., Sanderson, R., Lopez, S., Dijkstra, J., Kebreab, E., France, J.

Meta-analysis of phosphorus balance data from growing pigs (2007)

Schulin-Zeuthen, M., Kebreab, E., Gerrits, W.J.J., Lopez, S., Fan, M.Z., Dias, R.S., ...

Many studies have highlighted concerns over current methods of determining endogenous P losses and P requirements in growing pigs. Therefore, a database containing observations on 350 pigs was...

Tomography of the intergalactic medium with Ly-alpha forests in close QSO pairs (2006)

D'Odorico, V., Viel, M., Saitta, F., Cristiani, S., Bianchi, S., Boyle, B., ...

We study the three-dimensional distribution of non virialised matter at z~2 using high resolution spectra of QSO pairs and simulated spectra drawn from cosmological hydrodynamical simulations. We...

Sustainable Evaluation. Applying ecological principles and tools to natural resource management systems (2006)

Lopez, S., Masera, O.R., Leffelaar, P.A., Astier, M.

From nutrient requirement to animal response: predicting the profile of absorbed nutrients in dairy cattle (2006)

Dijkstra, J., Kebreab, E., Mills, J.A.N., Lopez, S., France, J.

Functions for microbial growth (2006)

Lopez, S., Prieto, M., Dijkstra, J., Kebreab, E., Dhanoa, M.S., France, J.

Supply and requirement of nutrients predicted by feed evaluation systems and a mechanistic model for dairy cattle offered grass-based diets (2006)

Dijkstra, J., Kebreab, E., Bannink, A., Crompton, L.A., Lopez, S., Abrahamse, P.A., ...

Application of the gas production technique to feed evaluation systems for ruminants (2005)

Dijkstra, J., Kebreab, E., Bannink, A., France, J., Lopez, S.

A range of feed evaluation techniques is available to predict the nutritional value of ruminant feedstuffs. The aim of this paper was to critically evaluate use of gas production (GP) data as inputs...

A general compartmental model for interpreting gas production profiles (2005)

France, J., Lopez, S., Kebreab, E., Bannink, A., Dhanoa, M.S., Dijkstra, J.

Equations to describe gas production profiles, obtained using manual or automated systems for in vitro fermentation of ruminant feeds, are derived from first principles using a general compartmental...

Assessment of the nutritive value of cereal and legume straws based on chemical composition and in vitro digestibility (2005)

Lopez, S., Davies, D., Dhanoa, M.S., Dijkstra, J., France, J.

The nutritive value of 17 straws was determined on the basis of their chemical composition, in vitro dry matter (DM) digestibility and rumen fermentation kinetics (from gas production curves measured...

Statistical evaluation of mathematical models for microbial growth (2004)

Lopez, S., Prieto, M., Dijkstra, J., Dhanoa, M.S., France, J.

The aim of this study was to evaluate the suitability of several mathematical functions for describing microbial growth curves. The nonlinear functions used were: three-phase linear, logistic,...

Technical note: a proposed method to determine the extent of degradation of a feed in the rumen from the degradation profile obtained with the in vitro gas production technique using feces as the inoculum (2004)

Dhanoa, M.S., France, J., Crompton, L.A., Mauricio, R.M., Kebreab, E., Mills, J.A.N., ...

A method is proposed to determine the extent of degradation in the rumen involving a two-stage mathematical modeling process. In the first stage, a statistical model shifts (or maps) the gas...

Effects of volatile fatty acid supply on their absorption and on water kinetics in the rumen of sheep sustained by intragastric infusions (2003)

Lopez, S., Hovell, F.D.D., Dijkstra, J., France, J.

A non-invasive approach to determining extent of degradation in the rumen (2001)

Crompton, L.A., France, J., Kebreab, E., Mills, J.A.N., Dhanoa, M.S., Lopez, S., ...

Estimating the extent of degradation of ruminant feeds from a description of their gas production profiles observed in vitro: comparison of models (2000)

Dhanoa, M.S., Lopez, S., Dijkstra, J., Davies, D.R., Sanderson, R., Williams, B.A., ...

An evaluation of general models that describe gas production profiles is presented. The models are derived from first principles by considering a simple three-pool scheme and permit the extent of...

Development and application of a mechanistic model to study substrate degradation, microbial synthesis and gas production (2000)

Dijkstra, J., France, J., Dhanoa, M.S., Lopez, S.

Simulation of substrate degradation, microbial synthesis and gas production in the gas production technique and in vivo (2000)

Dijkstra, J., France, J., Dhanoa, M.S., Lopez, S.

Estimating the extent of degradation of ruminant feeds from a description of their gas production profiles observed in vitro : derivation of models an other mathematical considerations (2000)

France, J., Dijkstra, J., Dhanoa, M.S., Lopez, S., Bannink, A.

Equations to describe gas production profiles, obtained using manual or automated systems for in vitro fermentation of ruminant feeds, were derived from first principles by considering a simple...

A non-invasive approach to determining extent of degradation in the rumen (2000)

France, J., Dhanoa, M.S., Crompton, L.A., Lopez, S., Dijkstra, J., Mauricio, R.M., ...

Prediction of energy supply in ruminants, with emphasis on forages (2000)

Lopez, S., Dijkstra, J., France, J.

Models to interpret degradation profiles obtained from in vitro and in situ incubation of ruminant feeds (2000)

Lopez, S., France, J., Dijkstra, J., Dhanoa, M.S.

Chemical composition and in vitro digestibility of by-products (in Spanish) (2000)

Lopez, S., Ranilla, M.J., Davies, D., Falagan, A., Dhanoa, M.S., Dijkstra, J., ...

Chemical composition and in vitro digestibility of cereal and legume straws (in Spanish) (2000)

Lopez, S., Ranilla, M.J., Davies, D., Llamazares, E., Dhanoa, M.S., Dijkstra, J., ...

A generalized Michaelis-Menten type equation for the analysis of growth (2000)

Lopez, S., France, J., Gerrits, W.J.J., Dhanoa, M.S., Humphries, D.J., Dijkstra, J.

The functional form W = (W0Kc Wf t(c)) /(Kc t(c)), where W is body size at age t, W0 and Wf are the zero- and infinite-time values of W, respectively, and K and c are constants, is derived. This new...

Correcting the calculation of extent of degradation to account for particulate matter loss at zero time when applying the polyester bag method (1999)

Dhanoa, M.S., France, J., Lopez, S., Dijkstra, J., Lister, S.J., Davies, D.R., ...

Effect of variation in volatile fatty acid profile and gas yield during incubation on simulated gas production and extent of ruminal degradation (in Dutch) (1999)

Dijkstra, J., France, J., Lopez, S., Dhanoa, M.S.

Impact of variation in yield of gas during incubation on simulated gas production and extent of ruminal degradation (short communication) (1999)

Dijkstra, J., France, J., Lopez, S., Dhanoa, M.S.

Comparison of mathematical models to describe disappearance curves obtained using the polyester bag technique for incubating feeds in the rumen (1999)

Lopez, S., France, J., Dhanoa, M.S., Mould, F., Dijkstra, J.

Models for interpreting in vitro gas production profiles from ruminant feeds. (1997)

France, J., Dijkstra, J., Lopez, S., Dhanoa, M.S.

Particulate matter loss and the nylon-bag method - Reply by France et al. (1997)

France, J., Lopez, S., Dijkstra, J., Dhanoa, M.S.

Consequences of model choice when analysing polyester bag data. (1996)

Dhanoa, M.S., France, J., Dijkstra, J., Lopez, S.