35 results on '"van Kempen T"'
Search Results
2. Dietary fibre enrichment of supplemental feed modulates the development of the intestinal tract in suckling piglets
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Van Hees, H. M. J., Davids, M., Maes, D., Millet, S., Possemiers, S., den Hartog, L. A., van Kempen, T. A. T. G., and Janssens, G. P. J.
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- 2019
- Full Text
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3. Water in Star-forming Regions with the Herschel Space Observatory (WISH). I. Overview of Key Program and First Results
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van Dishoeck, E. F., Kristensen, L. E., Benz, A. O., Bergin, E. A., Caselli, P., Cernicharo, J., Herpin, F., Hogerheijde, M. R., Johnstone, D., Liseau, R., Nisini, B., Shipman, R., Tafalla, M., van der Tak, F., Wyrowski, F., Aikawa, Y., Bachiller, R., Baudry, A., Benedettini, M., Bjerkeli, P., Blake, G. A., Bontemps, S., Braine, J., Brinch, C., Bruderer, S., Chavarría, L., Codella, C., Daniel, F., de Graauw, Th., Deul, E., di Giorgio, A. M., Dominik, C., Doty, S. D., Dubernet, M. L., Encrenaz, P., Feuchtgruber, H., Fich, M., Frieswijk, W., Fuente, A., Giannini, T., Goicoechea, J. R., Helmich, F. P., Herczeg, G. J., Jacq, T., Jørgensen, J. K., Karska, A., Kaufman, M. J., Keto, E., Larsson, B., Lefloch, B., Lis, D., Marseille, M., McCoey, C., Melnick, G., Neufeld, D., Olberg, M., Pagani, L., Panić, O., Parise, B., Pearson, J. C., Plume, R., Risacher, C., Salter, D., Santiago-García, J., Saraceno, P., Stäuber, P., van Kempen, T. A., Visser, R., Viti, S., Walmsley, M., Wampfler, S. F., and Yıldız, U. A.
- Published
- 2011
- Full Text
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4. Relationships between glycaemic index and digesta passage of cereal-based diets in pigs
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Solà-Oriol, D., van Kempen, T., and Torrallardona, D.
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- 2010
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5. Regulatory T cells in psoriatic arthritis: an IL-17A-producing, Foxp3intCD161 + RORγt + ICOS + phenotype, that associates with the presence of ADAMTSL5 autoantibodies.
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Pouw, J. N. Juliëtte, Nordkamp, M. A. M. Michel Olde, van Kempen, T. Tessa, Concepcion, A. N. Arno, van Laar, J. M. Jacob, van Wijk, F. Femke, Spierings, J. Julia, Leijten, E. F. A. Emmerik, and Boes, M. Marianne
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REGULATORY T cells ,MONONUCLEAR leukocytes ,PSORIATIC arthritis ,SYNOVIAL fluid ,JOINT pain ,T cells - Abstract
In psoriatic arthritis (PsA), predisposing class I HLA alleles, the presence of synovial clonally proliferated CD8 + T cells and autoantibodies all point towards the loss of immune tolerance. However, the key mechanisms that lead to immune dysregulation are not fully understood. In other types of inflammatory arthritis, T regulatory cell (Treg) dysfunction and plasticity at sites of inflammation were suggested to negatively affect peripheral tolerance. We here addressed if Treg variances associate with psoriatic disease. We collected clinical data, sera and peripheral blood mononuclear cells from 13 healthy controls, 21 psoriasis and 21 PsA patients. In addition, we obtained synovial fluid mononuclear cells from 6 PsA patients. We studied characteristics of CD4 + CD25 + CD127
lo Foxp3 + Tregs by flow cytometry and used ELISA to quantify antibodies against ADAMTSL5, a recently discovered autoantigen in psoriatic disease. In comparison with their circulating counterparts, Tregs from inflamed joints express increased levels of ICOS, CTLA-4 and TIGIT. Furthermore, synovial fluid-derived Tregs have a distinct phenotype, characterized by IL-17A production and upregulation of CD161 and RORγt. We identified a subset of Tregs with intermediate Foxp3 expression as the major cytokine producer. Furthermore, ICOS + Tregs associate with PsA disease activity as measured by PASDAS. Lastly, we observed that presence of the Foxp3int Tregs associates with an increased abundance of anti-ADAMTSL5 autoantibodies. Tregs derived from the inflammatory environment of inflamed PsA joints exhibit a distinct phenotype, which associates with loss of peripheral immune tolerance in psoriatic disease. [ABSTRACT FROM AUTHOR]- Published
- 2022
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6. Ammonia, volatile fatty acids, phenolics, and odor offensiveness in manure from growing pigs fed diets reduced in protein concentration
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Otto, E.R., Yokoyama, M., Hengemuehle, S., von Bermuth, R.D., van Kempen, T., and Trottier, N.L.
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Veterinary physiology -- Research ,Swine -- Physiological aspects ,Animal feeding and feeds -- Physiological aspects ,Odor control -- Research ,Zoology and wildlife conservation - Abstract
The objective of this study was to investigate whether reducing dietary CP concentration decreases fecal VFA, manure ammonia ([NH.sub.3]) emission and odor, and urinary phenolic metabolites. Six barrows were allotted to one of six dietary treatments in a Latin square design. Treatments consisted of four corn-soybean meal based diets containing 15, 12, 9, and 6% CP, a casein-based diet containing 15% CP, and a protein-free diet (0% protein). Crystalline AA were included in the 12, 9, and 6% CP diets. The casein-based and protein-free diets were used to determine basal endogenous contribution of VFA, phenolics, [NH.sub.3], and manure odor. Pigs were housed individually in metabolism cages to allow total collection of feces and urine. Feces and urine were collected and pooled within pig and period. Feces and urine were analyzed for VFA and phenolic metabolite concentrations, respectively. Feces and urine were then mixed, stored, and fermented at room temperature for 30 d. For [NH.sub.3] determination, headspace air was sampled from manure slurries at 24, 48, and 72 h after fermentation. Slurry samples were placed into vials, capped, and randomized before odor panel evaluation. Odor offensiveness was classified on severity: 1 = non-offensive; 2 = mildly offensive; 3 = moderately offensive; 4 = strongly offensive; and 5 = extremely offensive. Reducing dietary CP increased (P < 0.05) fecal VFA concentrations but did not affect phenolic concentrations in urine. Manure [NH.sub.3] emission was reduced (P < 0.05) as dietary CP concentration decreased from 15 to 0%. The 15% diet had the ]east offensive manure slurry with odor qualitative ranking of 2.58 (i.e., mild-moderately offensive). Compared with the 15% CP diet, manure from the 9 and 6% CP diets was found to be more offensive (P < 0.05), with qualitative rankings of 2.92 and 3.10, respectively. Odor qualitative rank for the 12% CP, protein-free diet, and casein-based diet did not differ from that of the 15% CP diet. These results indicate that reduction in dietary CP concentrations decreases manure [NH.sub.3] emission, but it does not diminish manure odor offensiveness and fecal VFA concentrations. Key Words: Ammonia, Manures, Odors, Phenolic Compounds, Pigs, Volatile Fatty Acids
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- 2003
7. Effect of hyperalimentation on body composition in swine
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Newcomb, M.D., Ott, R.S., van Kempen, T., Lan, Y.H., McKeith, F.K., Novakofski, J.E., Bechtel, P.J., and Easter, R.A.
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Enteral feeding -- Research ,Swine -- Food and nutrition ,Zoology and wildlife conservation - Abstract
Fifty growing pigs were used in two experiments to evaluate the effects of cannulation and hyperalimentation on performance and body composition responses. Surgical implantation of a cannula into the greater curvature of the stomach and subsequent management associated with maintenance of the cannula did not result in a reduction (P |is greater than~ .05) of voluntary feed intake. Cannulation did not negatively affect gain (P |is greater than~ .05). Over the entire trial, feed efficiency was not changed by cannulation (P |is greater than~ .05). Cannulation itself did not affect protein or fat deposition (P |is greater than~ .05) in the carcass. Hyperalimentation to approximately 120% of control intake resulted in increased daily gain (P |is less than~ .05) and similar feed efficiency (P |is greater than~ .05) compared with that of control animals. Hyperalimentation decreased protein deposition (P |is less than~ .05) and tended to increase fat deposition.
- Published
- 1993
8. DeGaS-MC: Dense Gas Survey in the Magellanic Clouds: I. An APEX survey of HCO+ and HCN(2−1) toward the LMC and SMC.
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Galametz, M., Schruba, A., De Breuck, C., Immer, K., Chevance, M., Galliano, F., Gusdorf, A., Lebouteiller, V., Lee, M. Y., Madden, S. C., Polles, F. L., and van Kempen, T. A.
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MAGELLANIC clouds ,SMALL magellanic cloud ,LARGE magellanic cloud ,GAS reservoirs ,MOLECULAR clouds ,STAR formation - Abstract
Context. Understanding the star-forming processes is key to understanding the evolution of galaxies. Investigating star formation requires precise knowledge of the properties of the dense molecular gas complexes where stars form and a quantification of how they are affected by the physical conditions to which they are exposed. The proximity, low metallicity, and wide range of star formation activity of the Large and Small Magellanic Clouds (LMC and SMC) make them prime laboratories to study how local physical conditions impact the dense gas reservoirs and their star formation efficiency. Aims. The aim of the Dense Gas Survey for the Magellanic Clouds (DeGaS-MC) project is to expand our knowledge of the relation between dense gas properties and star formation activity by targeting the LMC and SMC observed in the HCO
+ (2−1) and HCN(2−1) transitions. Methods. We carried out a pointing survey targeting two lines toward ∼30 LMC and SMC molecular clouds using the SEPIA180 instrument installed on the Atacama Pathfinder EXperiment (APEX) telescope. We performed a follow-up mapping campaign of the emission in the same transition in 13 star-forming regions. This first paper provides line characteristic catalogs and integrated line-intensity maps of the sources. Results. HCO+ (2−1) is detected in 20 and HCN(2−1) in 8 of the 29 pointings observed. The dense gas velocity pattern follows the line-of-sight velocity field derived from the stellar population. The three SMC sources targeted during the mapping campaign were unfortunately not detected in our mapping campaign but both lines are detected toward the LMC 30Dor, N44, N105, N113, N159W, N159E, and N214 regions. The HCN emission is less extended than the HCO+ emission and is restricted to the densest regions. The HCO+ (2−1)/HCN(2−1) brightness temperature ratios range from 1 to 7, which is consistent with the large ratios commonly observed in low-metallicity environments. A larger number of young stellar objects are found at high HCO+ intensities and lower HCO+ /HCN flux ratios, and thus toward denser lines of sight. The dense gas luminosities correlate with the star formation rate traced by the total infrared luminosity over the two orders of magnitude covered by our observations, although substantial region-to-region variations are observed. [ABSTRACT FROM AUTHOR]- Published
- 2020
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9. Feed intake patterns nor growth rates of pigs are affected by dietary resistant starch, despite marked differences in digestion.
- Author
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van Erp, R. J. J., de Vries, S., van Kempen, T. A. T. G., Den Hartog, L. A., and Gerrits, W. J. J.
- Abstract
Current feed evaluation systems often assume that fermented starch (i.e. resistant starch (RS)) yields less energy than digested starch. However, growth rates of pigs fed low and high RS diets are often the same when feed is available ad libitum. This may be explained by its effect on digestive processes changing feeding behavior, and consequently energy utilization. This study aims to investigate the effect of RS on nutrient digestion and digesta passage rate in pigs, in combination with its effect on feeding behavior and growth performance under ad libitum conditions. In experiment 1, 20 male pigs (40 ± 2.82 kg) were fed diets containing either 50% waxy maize starch (low in RS (LRS)) or high-amylose maize starch (high in RS (HRS)), and soluble and insoluble indigestible markers. After 14 days of adaptation to the diets, pigs were fed hourly to reach steady state (6 h), dissected, and digesta were collected from eight segments. From the collected samples, nutrient digestion and passage rate of the solid and liquid digesta fraction were determined. In experiment 2, 288 pigs (80 ± 0.48 kg; sex ratio per pen 1 : 1; boar : gilt) were housed in groups of 6. Pigs were ad libitum-fed one of the experimental diets, and slaughtered at approximately 115 kg. Feed intake, growth and carcass parameters were measured. Ileal starch digestibility was greater for LRS-fed than for HRS-fed pigs (98.0% v. 74.0%; P < 0.001), where the additional undigested starch in HRS-fed pigs was fermented in the large intestine. No effects of RS on digesta passage rate of the solid or liquid digesta fraction and on feeding behavior were observed. Growth rate and feed intake did not differ between diets, whereas feed efficiency of HRS-fed pigs was 1%-unit higher than that of LRS-fed pigs (P = 0.041). The efficiency of feed used for carcass gain did not differ between diets indicating that the difference in feed efficiency was determined by the non-carcass fraction. Despite a 30% greater RS intake (of total starch) with HRS than with LRS, carcass gain and feed efficiency used for carcass gain were unaffected. RS did not affect digesta passage rate nor feeding behavior suggesting that the difference in energy intake between fermented and digested starch is compensated for post-absorptively. Our results indicate that the net energy value of fermented starch currently used in pig feed evaluation systems is underestimated and should be reconsidered. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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10. Dietary adipic acid reduces ammonia emission from swine excreta
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van Kempen, T. A. T. G.
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Swine -- Physiological aspects ,Adipic acid -- Health aspects ,Ammonia in animal nutrition -- Physiological aspects ,Zoology and wildlife conservation - Abstract
Adipic acid is only partially catabolized when it is fed to animals, and a portion of it is excreted in urine. The excreted portion may lower urinary pH and, as a result, ammonia emission. The present study tested this hypothesis. In Exp. 1, nursery pigs (n = 14) were fed (for a period of 7 d) either a standard nursery diet or the same diet supplemented with 1% adipic acid to assess effects on urinary pH (collected on d 5 or 6) and in vitro ammonia emission from the collected urine samples that were mixed with control feces. In Exp. 2, grower pigs housed 10 each in one of two chambers were fed a control diet or the same diet supplemented with 1% adipic acid. Ventilated air was quantified and analyzed for ammonia using Fourier transform infrared spectroscopy to determine the effects of feeding 1% adipic acid on ammonia emission. The results from Exp. 1 showed that adipic acid strongly reduced urinary pH (from 7.7 to 5.5, P [is less than] 0.05). In vitro ammonia emission from these urine samples was significantly reduced at all the time points evaluated (1, 3, 18, and 46 h with reductions of 94, 93, 70, and 39%, respectively, P [is less than] 0.05). Experiment 2 showed that adipic acid supplementation reduced ammonia emission by 25% (P [is less than] 0.05), which corresponded to the predicted reduction in ammonia emission based on the reduction in manure pH observed. In conclusion, feeding adipic acid lowers urinary pH and reduces ammonia emission. The reduction in ammonia emission, though, does not correspond to the reduction in urinary pH but corresponds to the reduction in fecal pH as a result of mixing the urine and feces, in which feces act as a strong buffer. Key Words: Adipic Acid, Ammonia, pH, Pigs, Urine
- Published
- 2001
11. Adipic acid increases plasma lysine but does not improve the efficiency of lysine utilization in swine
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van Kempen, T. A. T. G., van Heugten, E., and Trottier, N. L.
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Swine -- Physiological aspects ,Adipic acid -- Physiological aspects ,Lysine -- Physiological aspects ,Zoology and wildlife conservation - Abstract
Adipic acid, upon catabolism, results in intermediates that bear a structural similarity to lysine degradation products. The objectives of this research were to determine whether adipic acid affects lysine concentrations in plasma and to evaluate whether adipic acid improves the efficiency of lysine utilization in pigs. In Exp. 1, nursery pigs (n = 14) were fed (for a period of 7 d) either a standard nursery diet or the same diet supplemented with 1% adipic acid to assess effects on plasma amino acid concentrations (plasma collected on d 7). In Exp. 2, nursery pigs (n = 56) were fed (for a period of 15 d) either a control diet or the same diet but deficient in either lysine, threonine, or tryptophan with or without supplemental adipic acid to assess the effects of adipic acid on the efficiency of amino acid utilization. The results from Exp. 1 showed that adipic acid increased plasma lysine (by 18%) but not [Alpha]-amino adipic acid, an intermediate in lysine degradation. Experiment 2 demonstrated that adipic acid did not increase the efficiency of utilization of lysine, threonine, or tryptophan. The lack of effects on [Alpha]-amino adipic acid in Exp. 1 and the lack of a positive effect on the efficiency of utilization of lysine, threonine, and tryptophan suggest that adipic acid does not inhibit the mitochondrial uptake of lysine and(or) its degradation in the mitochondrion. It is concluded that feeding adipic acid increases plasma lysine but does not improve the efficiency of lysine utilization. Key Words: Adipic Acid, Lysine, Pigs
- Published
- 2001
12. Effects of dietary carbohydrates and buffering capacity on nutrient digestibility and manure characteristics in finishing pigs
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Mroz, Z., Moeser, A. J., Vreman, K., van Diepen, J. T. M., van Kempen, T., Canh, T. T., and Jongbloed, A. W.
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Swine -- Food and nutrition ,Carbohydrates -- Research ,Zoology and wildlife conservation - Abstract
A 2 x 3 factorial experiment was conducted with 24 finishing pigs (Yorkshire x [Finnish Landrace x Dutch Landrace]) to determine the effects of dietary buffering capacity (BC) and carbohydrate sources on apparent total tract digestibility (TD), N retention, and manure characteristics. Twelve of these pigs were fitted with steered ileo-cecal value cannulas to measure the apparent ileal digestibility (ID) of N. Experimental variables were two levels of BC (High = 600 mEq/kg and Low = 530 mEq/kg) and three dietary carbohydrates (tapioca [28%], soybean hulls [25%], and sugar beet pulp [25%]). The two levels of BC were achieved by adjusting the amounts of alkalogenic limestone and acidogenic Ca sulfate in the diet. Pigs were fed twice daily at 2.4 x maintenance requirement for metabolizable energy (418 kJ ME/[BW.sup.0.75]). Chromic oxide was used as an indigestible marker. Feces and urine were collected over 5 d for nutrient balance and in vitro measurements of pH and ammonia emission over 7 d. No significant interactions between BC and dietary carbohydrates on the ID, TD, N retention, or manure characteristics were observed. Lowering BC with Ca sulfate did not affect digestibility of most nutrients, except for a negative impact on the TD of Ca (P = 0.015) and Mg (P = 0.003). Although all pigs receiving Ca sulfate had more acidic urine (by 0.49 pH units; P = 0.001), ammonia emission from manure was not lowered, irrespective of the carbohydrate source. Carbohydrates affected significantly the ID and TD of most nutrients, whereas N retention remained similar (P [is greater than] 0.10). Urinary N:fecal N ratios in manure of pigs fed diets with tapioca, soybean hulls, and beet pulp were 2.09, 1.35, and 1.67, respectively. These ratios corresponded with in vitro ammonia emission (169, 125, and 148 mmol/7 d; P = 0.023). In conclusion, these results indicate that the acidification of urine in pigs fed Ca sulfate in the presence of NSP-rich carbohydrates was achieved. However, acidity of manure and ammonia emission were not affected. The addition of NSP from soybean hulls and(or) sugar beet pulp reduced ratios of urinary:fecal N, and thereby ammonia emission. Key Words: Ammonia, Balance Studies, Buffering Capacity, Carbohydrates, Digestibility, Pigs
- Published
- 2000
13. Phase correction for ALMA. Investigating water vapour radiometer scaling: The long-baseline science verification data case study.
- Author
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Maud, L. T., Tilanus, R. P. J., van Kempen, T. A., Hogerheijde, M. R., Schmalzl, M., Yoon, I., Contreras, Y., Toribio, M. C., Asaki, Y., Dent, W. R. F., Fomalont, E., and Matsushita, S.
- Subjects
ATMOSPHERIC water vapor ,RADIOMETERS ,TROPOSPHERE ,SIGNAL-to-noise ratio - Abstract
The Atacama Large millimetre/submillimetre Array (ALMA) makes use of water vapour radiometers (WVR), which monitor the atmospheric water vapour line at 183 GHz along the line of sight above each antenna to correct for phase delays introduced by the wet component of the troposphere. The application of WVR derived phase corrections improve the image quality and facilitate successful observations in weather conditions that were classically marginal or poor. We present work to indicate that a scaling factor applied to the WVR solutions can act to further improve the phase stability and image quality of ALMA data. We find reduced phase noise statistics for 62 out of 75 datasets from the long-baseline science verification campaign after a WVR scaling factor is applied. The improvement of phase noise translates to an expected coherence improvement in 39 datasets. When imaging the bandpass source, we find 33 of the 39 datasets show an improvement in the signal-to-noise ratio (S/N) between a few to ~30 percent. There are 23 datasets where the S/N of the science image is improved: 6 by <1%, 11 between 1 and 5%, and 6 above 5%. The higher frequencies studied (band 6 and band 7) are those most improved, specifically datasets with low precipitable water vapour (PWV), < mm, where the dominance of the wet component is reduced. Although these improvements are not profound, phase stability improvements via the WVR scaling factor come into play for the higher frequency (>450 GHz) and long-baseline (>5 km) observations. These inherently have poorer phase stability and are taken in low PWV (< mm) conditions for which we find the scaling to be most effective. A promising explanation for the scaling factor is the mixing of dry and wet air components, although other origins are discussed. We have produced a python code to allow ALMA users to undertake WVR scaling tests and make improvements to their data. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
14. Origin of warm and hot gas emission from low-mass protostars: Herschel-HIFI observations of CO J = 16-15 I. Line profiles, physical conditions, and H2O abundance.
- Author
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Kristensen, L. E., van Dishoeck, E. F., Mottram, J. C., Karska, A., Yıldız, U. A., Bergin, E. A., Bjerkeli, P., Cabrit, S., Doty, S., Evans II, N. J., Gusdorf, A., Harsono, D., Herczeg, G. J., Johnstone, D., Jørgensen, J. K., van Kempen, T. A., Lee, J.-E., Maret, S., Tafalla, M., and Visser, R.
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PROTOSTARS ,STELLAR activity ,INTERSTELLAR molecules ,STAR formation ,STELLAR mass ,ASTROCHEMISTRY - Abstract
Context. Through spectrally unresolved observations of high-J CO transitions, Herschel Photodetector Array Camera and Spectrometer (PACS) has revealed large reservoirs of warm (300 K) and hot (700 K) molecular gas around low-mass protostars. The excitation and physical origin of this gas is still not understood. Aims. We aim to shed light on the excitation and origin of the CO ladder observed toward protostars, and on the water abundance in different physical components within protostellar systems using spectrally resolved Herschel-HIFI data. Methods. Observations are presented of the highly excited CO line J = 16-15 (E
up /kB = 750 K) with the Herschel Heterodyne Instrument for the Far Infrared (HIFI) toward a sample of 24 low-mass protostellar objects. The sources were selected from the Herschel "Water in Star-forming regions with Herschel" (WISH) and "Dust, Ice, and Gas in Time" (DIGIT) key programs. Results. The spectrally resolved line profiles typically show two distinct velocity components: a broad Gaussian component with an average FWHM of 20 km s-1 containing the bulk of the flux, and a narrower Gaussian component with a FWHM of 5 km s-1 that is often offset from the source velocity. Some sources show other velocity components such as extremely-high-velocity features or "bullets". All these velocity components were first detected in H2O line profiles. The average rotational temperature over the entire profile, as measured from comparison between CO J = 16-15 and 10-9 emission, is ~300 K. A radiative-transfer analysis shows that the average H2O/CO column-density ratio is ~0.02, suggesting a total H2O abundance of ~2 × 10-6 , independent of velocity. Conclusions. Two distinct velocity profiles observed in the HIFI line profiles suggest that the high-J CO ladder observed with PACS consists of two excitation components. The warm PACS component (300 K) is associated with the broad HIFI component, and the hot PACS component (700 K) is associated with the offset HIFI component. The former originates in either outflow cavity shocks or the disk wind, and the latter in irradiated shocks. The low water abundance can be explained by photodissociation. The ubiquity of the warm and hot CO components suggest that fundamental mechanisms govern the excitation of these components; we hypothesize that the warm component arises when H2 stops being the dominant coolant. In this scenario, the hot component arises in cooling molecular H2-poor gas just prior to the onset of H2 formation. High spectral resolution observations of highly excited CO transitions uniquely shed light on the origin of warm and hot gas in low-mass protostellar objects. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
15. Vitamin E plasma kinetics in swine show low bioavailability and short half-life of all-rac-a-tocopheryl acetate.
- Author
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van Kempen, T. A. T. G., Reijersen, M. H., de Bruijn, C., De Smet, S., Michiels, J., Traber, M. G., and Lauridsen, C.
- Subjects
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VITAMIN E , *PIGLETS , *ANIMALS , *LIQUID chromatography , *OXIDATIVE stress , *OXIDATION-reduction reaction - Abstract
Vitamin E is important for animal production because of its effects on health and product quality, but the amount and form required remains controversial. Our objective was to quantify the absolute bioavailability of oral all-rac-α-tocopheryl acetate (α-TAc) in swine (22 ± 1 kg and 8 wk old, fitted with jugular catheters) adapted to a diet supplemented with 75 mg/kg all-rac-α-TAc; 75 mg/kg was chosen because this level represents the nonweighted average inclusion level in piglet diets across Western key swine-producing countries. For this, a 350-g test meal (6% fat) was supplied at time 0 containing 75 mg deuterated (D9) all-rac-α-TAc to 9 animals, and 8 animals received an intravenous (i.v.) dose containing deuterated (D6) RRR-α-tocopherol (α-T) at one-eighth the oral dose and a test meal without supplemental vitamin E. Plasma samples (12 to 13 per animal) were obtained at incremental intervals over 75 h for analysis of deuterated α-T using liquid chromatography--tandem mass spectrometry. Surprisingly, the i.v. dose rapidly disappeared from plasma and then reappeared. The half-life for this first peak was only 1.7 ± 0.3 min. The second peak had an appearance rate (Ka) of 0.10 ± 0.06 d-1 and a half-life of 5.9 ± 1.2 h. Oral dosing resulted, after a lag of 56 min, in a Ka of 0.91 ± 0.21 d-1 and a half-life of 2.6 ± 0.8 h. The bioavailability for oral α-TAc was 12.5%, whereas the area under the curve was only 5.4%. This low bioavailability, small area under the curve, and short half-life are likely because of various factors, that is, the use of only 6% fat in the diet, the use of the acetate ester and all-rac, and the high dose relative to requirements. In conclusion, i.v. dosed vitamin E shows both a rapid and a very slow pool, whereas orally dosed vitamin E shows a single slow pool. The oral material has a very short half-live (44% of i.v. or 2.6 h), low bioavailability (12.5%), and a very small area under the curve (5.4%), bringing into question the efficacy of typical doses of vitamin E in swine diets for alleviating oxidative stress. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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- View/download PDF
16. Outflow forces in intermediate-mass star formation.
- Author
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van Kempen, T. A., Hogerheijde, M. R., van Dishoeck, E. F., Kristensen, L. E., Belloche, A., Klaassen, P. D., Leurini, S., San Jose-Garcia, I., Aykutalp, A., Choi, Y., Endo, A., Frieswijk, W., Harsono, D., Karska, A., Koumpia, E., van der Marel, N., Nagy, Z., Pérez-Beaupuits, J.-P., Risacher, C., and van Weeren, R. J.
- Subjects
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STELLAR evolution , *STELLAR mass , *PROTOSTARS , *STELLAR luminosity function , *RADIATIVE transfer equation - Abstract
Context. Protostars of intermediate-mass provide a bridge between theories of low- and high-mass star formation. Molecular outflows emerging from such sources can be used to determine the influence of fragmentation and multiplicity on protostellar evolution through the apparent correlation of outflow forces of intermediate-mass protostars with the total luminosity instead of the individual luminosity. Aims. The aim of this paper is to derive outflow forces from outflows of six intermediate-mass protostellar regions and validate the apparent correlation between total luminosity and outflow force seen in earlier work, as well as remove uncertainties caused by different methodologies. Methods. By comparing CO 6–5 observations obtained with APEX with non-LTE radiative transfer model predictions, the optical depths, temperatures and densities of the gas of the molecular outflows are derived. Outflow forces, dynamical timescales, and kinetic luminosities are subsequently calculated. Results. Outflow parameters, including the forces, were derived for all sources. Temperatures in excess of 50 K were found for all flows, in line with recent low-mass results. However, comparison with other studies could not corroborate conclusions from earlier work on intermediate-mass protostars which hypothesized that fragmentation enhances outflow forces in clustered intermediate-mass star formation. Any enhancement in comparison with the classical relation between outflow force and luminosity can be attributed to the use of a higher excitation line and improvement in methods. They are in line with results from low-mass protostars using similar techniques. Conclusions. The role of fragmentation on outflows is an important ingredient to understand clustered star formation and the link between low- and high-mass star formation. However, detailed information on spatial scales of a few 100 AU, covering all individual members is needed to make the necessary progress. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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17. Testing particle trapping in transition disks with ALMA.
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Pinilla, P., van der Marel, N., Pérez, L. M., van Dishoeck, E. F., Andrews, S., Birnstiel, T., Herczeg, G., Pontoppidan, K. M., and van Kempen, T.
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PROTOPLANETARY disks ,SPECTRUM analysis ,GAUSSIAN distribution ,AXIAL flow ,DUST - Abstract
Some protoplanetary disks show evidence of inner dust cavities. Recent observations of gas and dust of these so-called transition disks support the hypothesis that these cavities originate from particle trapping in pressure bumps. We present new Atacama Large Millimeter/submillimeter Array (ALMA) continuum observations at 336 GHz of two transition disks, SR21 and HD 135344B. In combination with previous ALMA observations from Cycle 0 at 689 GHz, we compare the visibility profiles at the two frequencies and calculate the spectral index (α
mm ). The observations of SR 21 show a clear shift in the visibility nulls, indicating radial variations of the inner edge of the cavity at the two wavelengths. Notable radial variations of the spectral index are also detected for SR 21 with values of αmm ~ 3:8-4:2 in the inner region (r ≲ 35 AU) and αmm ~ 2:6-3:0 outside. An axisymmetric ring (which we call the ring model) or a ring with the addition of an azimuthal Gaussian profile, for mimicking a vortex structure (which we call the vortex model), is assumed for fitting the disk morphology. For SR 21, the ring model better fits the emission at 336 GHz, conversely the vortex model better fits the 689 GHz emission. For HD 135344B, neither a significant shift in the null of the visibilities nor radial variations of αmm are detected. Furthermore, for HD 135344B, the vortex model fits both frequencies better than the ring model. However, the azimuthal extent of the vortex increases with wavelength, contrary to model predictions for particle trapping by anticyclonic vortices. For both disks, the azimuthal variations of αmm remain uncertain to confirm azimuthal trapping. The comparison of the current data with a generic model of dust evolution that includes planet-disk interaction suggests that particles in the outer disk of SR 21 have grown to millimetre sizes and have accumulated in a radial pressure bump, whereas with the current resolution there is not clear evidence of radial trapping in HD 135344B, although it cannot be excluded either. [ABSTRACT FROM AUTHOR]- Published
- 2015
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18. Far-infrared CO and H2O emission in intermediate-mass protostars (Research Note).
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Matuszak, M., Karska, A., Kristensen, L. E., Herczeg, G. J., Tychoniec, Ł., van Kempen, T. A., and Fuente, A.
- Subjects
PROTOSTARS ,INTERSTELLAR molecules ,STELLAR luminosity function ,STELLAR rotation ,STELLAR spectra - Abstract
Context. Intermediate-mass young stellar objects (YSOs) provide a link to understanding how feedback from shocks and UV radiation scales from low- to high-mass star forming regions. Aims. Our aim is to analyze excitation of CO and H
2 O in deeply embedded intermediate-mass YSOs and compare it with similar studies on low-mass and high-mass YSOs. Methods. Herschel/PACS spectral maps are analyzed for six YSOs with bolometric luminosities of Lbol ~10²-10³ Lδ The maps cover spatial scales of ~104 AU in several CO and H2 O lines located in the ~55-210 μm range. Results. Rotational diagrams of CO show two temperature components at Trot ~ 320 K and Trot ~ 700-800 K, comparable to lowand high-mass protostars probed at similar spatial scales. The diagrams for H2 O show a single component at Trot ~ 130 K, as seen in low-mass protostars, and about 100 K lower than in high-mass protostars. Since the uncertainties in Trot are on the same order as the difference between the intermediate and high-mass protostars, we cannot conclude whether the change in rotational temperature occurs at a specific luminosity or whether the change is more gradual from low- to high-mass YSOs. Conclusions. Molecular excitation in intermediate-mass protostars is comparable to the central 10³ AU of low-mass protostars and consistent within the uncertainties with the high-mass protostars probed at 3 x 10³ AU scales, suggesting similar shock conditions in all those sources. [ABSTRACT FROM AUTHOR]- Published
- 2015
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19. The ALMA Band 9 receiver.
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Baryshev, A. M., Hesper, R., Mena, F. P., Klapwijk, T. M., van Kempen, T. A., Hogerheijde, M. R., Jackson, B. D., Adema, J., Gerlofsma, G. J., Bekema, M. E., Barkhof, J., de Haan-Stijkel, L. H. R., van den Bemt, M., Koops, A., Keizer, K., Pieters, C., van het Jagt, J. Koops, Schaeffer, H. H. A., Zijlstra, T., and Kroug, M.
- Subjects
HETERODYNE reception ,INTERMEDIATE frequency amplifiers ,SUPERCONDUCTOR-insulator-superconductor devices ,SUBMILLIMETER astronomy ,LINEAR polarization - Abstract
Aims. We describe the design, construction, and characterization of the Band 9 heterodyne receivers (600-720 GHz) for the Atacama Large Millimeter/submillimeter Array (ALMA). First-light Band 9 data, obtained during ALMA commissioning and science verification phases, are presented as well. Methods. The ALMA Band 9 receiver units (so-called "cartridges"), which are installed in the telescope's front end, have been designed to detect and down-convert two orthogonal linear polarization components of the light collected by the ALMA antennas. The light entering the front end is refocused with a compact arrangement of mirrors, which is fully contained within the cartridge. The arrangement contains a grid to separate the polarizations and two beam splitters to combine each resulting beam with a local oscillator signal. The combined beams are fed into independent double-sideband mixers, each with a corrugated feedhorn coupling the radiation by way of a waveguide with backshort cavity into an impedance-tuned superconductor-insulator-superconductor (SIS) junction that performs the heterodyne down-conversion. Finally, the generated intermediate frequency (IF) signals are amplified by cryogenic and room-temperature HEMT amplifiers and exported to the telescope's IF back end for further processing and, finally, correlation. Results. The receivers have been constructed and tested in the laboratory and they show an excellent performance, complying with ALMA requirements. Performance statistics on all 73 Band 9 receivers are reported. Importantly, two di erent tunnel-barrier technologies (necessitating di erent tuning circuits) for the SIS junctions have been used, namely conventional AlO
x barriers and the more recent high-current-density AlN barriers. On-sky characterization and tests of the performance of the Band 9 cartridges are presented using commissioning data. Continuum and line images of the low-mass protobinary IRAS 16293-2422 are presented which were obtained as part of the ALMA science verification program. An 8 GHz wide Band 9 spectrum extracted over a 0:3"×0:3" region near source B, containing more than 100 emission lines, illustrates the quality of the data. [ABSTRACT FROM AUTHOR]- Published
- 2015
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20. Inclusion of Coastal Bermuda grass (BG) in feed negatively affects energy digestibility but not feed efficiency in swine. (Nonruminant Nutrition)
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Kim, I.B., Hansen, B., Hansen, J., Dvorak, R., van Heugten, E., and van Kempen, T.
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Bermuda grass -- Health aspects ,Animal nutrition -- Research ,Swine -- Food and nutrition ,Zoology and wildlife conservation - Abstract
Three trials were conducted to evaluate the nutritional value of BG with or without Fibrozyme[R]. In Exp. 1, eight barrows (129kg) were used to study fecal digestibility of 14.5% BG supplemented to a corn-soy diet with/without 0.02% Fibrozyme. Diets were fed at 70g x [kg.sup.-0.75] x [day.sup.-1] and tested in a Latin square design. Each period consisted of 5-d adaptation and 2-d collection of freshly voided feces. BG decreased gross energy (E) digestibility 14% (P Key Words: Bermuda grass, Energy and nitrogen, Sow and finisher
- Published
- 2001
21. Feeding degermed, dehulled corn to reduce nutrient excretion and improve performance in pigs. (Graduate Student Competitive Research Papers)
- Author
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Moeser, A.J., Kim, I.B., van Heugten, E., and van Kempen, T.
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Excretion -- Physiological aspects ,Animal nutrition -- Physiological aspects ,Corn -- Physiological aspects ,Swine -- Food and nutrition ,Zoology and wildlife conservation - Abstract
Two experiments were designed to assess the feeding value and potential environmental benefits of feeding a low fiber by-product originating from the corn dry milling process (degermed, dehulled corn, DGDH) to pigs. Twelve 27-kg barrows were used in Exp. 1 to evaluate nitrogen (N) and energy digestibility of DGDH compared to regular corn. Animals were individually housed in metabolism cages in which feces and urine was collected. Two diets were formulated to contain either 96.4% of DGDH or regular corn plus supplemental vitamins and minerals. Chromic oxide was used as an indigestible marker. Digestibilities of DM, N, and energy were greater in DGDH (93.4, 89.1, and 92.9%, respectively) compared to regular corn (84.9, 67.9, and 83.5%, respectively) (P < .01). Overall, a 56 and 39% reduction in DM and N excretion, respectively, was observed. In Exp. 2, 96 nursery pigs with initial BW of 8.8 kg, blocked by weight and gender, with 4 pigs/pen, were used in a 28-d growth performance study. Two starter diets were formulated to contain either DGDH (56%) or regular corn (58%) as the major grain source. Diets were formulated on a ME and digestible lysine basis to meet NRC requirements for this weight category of pig. At the end of the study, 24 pigs (1 from each pen) were slaughtered and gastrointestinal tract measurements were taken. Daily growth rates of pigs were the same between diets (0.64 kg/d). Feeding DGDH to pigs resulted in a 4% improvement in feed efficiency over regular corn (P < .05). The full intestinal tract weight of pigs fed DGDH tended to be 6% lighter (P=.07), likely due to a trend towards 10% less gutfill and 4% less intestinal mass. Results from these trials suggest that corn processed to remove poorly digestible fiber fractions provides more digestible nutrients than regular corn. As a result, DGDH reduces fecal and N excretion, thus providing a novel approach for reducing waste production. Key Words: Nutrient excretion, Digestibility, Pigs
- Published
- 2001
22. The origin of organic emission in NGC 2071.
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van Kempen, T. A., McCoey, C., Tisi, S., Johnstone, D., and Fich, M.
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- *
SUBMILLIMETER astronomy , *EMISSION-line galaxies , *RADIATIVE transfer , *SPUTTERING (Physics) , *INTERSTELLAR medium , *PROTOSTARS , *CIRCUMSTELLAR matter - Abstract
Context. The physical origin behind organic emission lines in embedded low-mass star formation has been fiercely debated over the last two decades. A multitude of scenarios have been proposed, from a hot corino to PDRs on cavity walls to shock excitation. Aims. The aim of this paper is to determine the location and the corresponding physical conditions of the gas responsible for organics emission lines. The outflows around the small protocluster NGC 2071 are an ideal testbed that can be used to di erentiate between various scenarios. Methods. Using Herschel-HIFI and the Submillimeter Array, observations of CH3OH, H2CO, and CH3CN emission lines over a wide range of excitation energies were obtained. Comparisons to a grid of radiative transfer models provide constraints on the physical conditions. Comparison to H2O line shape is able to trace gas-phase synthesis versus a sputtered origin. Results. Emission of organics originates in three separate spots: the continuum sources IRS 1 ("B") and IRS 3 ("A") and a new outflow position ("F"). Densities are above 107 cm-3 and temperatures between 100 K and 200 K. CH3OH emission observed with HIFI originates in all three regions and cannot be associated with a single region. Very little organic emission originates outside of these regions. Conclusions. Although the three regions are small (<1500 AU), gas-phase organics likely originate from sputtering of ices as a result of outflow activity. The derived high densities (>107 cm-3) are likely a requirement for organic molecules to survive from being immediately destroyed by shock products after evaporation. The lack of spatially extended emission confirms that organic molecules cannot (re-)form through gas-phase synthesis, as opposed to H2O, which shows strong line wing emission. The lack of CH3CN emission at "F" is evidence for a di erent history of ice processing because of the absence of a protostar at that location and recent ice mantle evaporation. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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23. Identifying the limitations for growth in low performing piglets from birth until 10 weeks of age.
- Author
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Paredes, S. P., Jansman, A. J. M., Verstegen, M. W. A., den Hartog, L. A., van Hees, H. M. J., Bolhuis, J. E., van Kempen, T. A. T. G., and Gerrits, W. J. J.
- Abstract
The evolution of hyper-prolific pig breeds has led to a higher within-litter variation in birth weight and in BW gain during the nursery phase. Based on an algorithm developed in previous research, two populations from a pool of 368 clinically healthy piglets at 6 weeks of age were selected: a low (LP) and a high (HP) performing population and their development was monitored until the end of the nursery phase (10 weeks of age). To understand the cause of the variation in growth between these populations we characterized the LP and HP piglets in terms of body morphology, behaviour, voluntary feed intake, BW gain, and apparent total tract and ileal nutrient digestibility. Piglets were housed individually and were fed a highly digestible diet. At selection, 6 weeks of age, the BW of LP and HP piglets were 6.8±0.1 and 12.2±0.1 kg, respectively. Compared with the LP piglets the HP piglets grew faster (203 g/day), ate more (275 g/day) from 6 to 10 weeks of age and were heavier at 10 weeks (30.0 v. 18.8 kg, all P<0.01). Yet, the differences in average daily gain and average daily feed intake disappeared when compared per kg BW0.75. Assuming similar maintenance requirements per kg BW0.75 the efficiency of feed utilization above maintenance was 0.1 g/g lower for the LP piglets (P=0.09).The gain : feed ratio was similar for both groups. LP piglets tended to take more time to touch a novel object (P=0.10), and spent more time eating (P<0.05). At 10 weeks, LP piglets had a higher body length and head circumference relative to BW (P<0.01). Relative to BW, LP had a 21% higher small intestine weight; 36% longer length, and relative to average FI, the small intestinal weight was 4 g/kg higher (both P=<0.01). Apparent total tract and ileal dry matter, N and gross energy digestibility were similar between groups (P>0.10). We concluded that the low performance of the LP piglets was due to their inability to engage compensatory gain or compensatory feed intake as efficiency of nutrient utilization and feed intake per kg BW0.75 was unaffected. LP piglets tend to be more fearful towards novel objects. The morphological comparisons, increased body length and head circumference relative to BW imply that LP piglets have an increased priority for skeletal growth. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
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24. Warm formaldehyde in the Ophiuchus IRS 48 transitional disk.
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van der Marel, N., van Dishoeck, E. F., Bruderer, S., and van Kempen, T. A.
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FORMALDEHYDE ,PROTOPLANETARY disks ,CHEMICAL models ,PLANETESIMALS ,STAR formation - Abstract
Context. Simple molecules such as H
2 CO and CH3 OH in protoplanetary disks are the starting point for the production of more complex organic molecules. So far, the observed chemical complexity in disks has been limited because of freeze-out of molecules onto grains in the bulk of the cold outer disk. Aims. Complex molecules can be studied more directly in transitional disks with large inner holes because these have a higher potential of detection through the UV heating of the outer disk and the directly exposed midplane at the wall. Methods. We used Atacama Large Millimeter/submillimeter Array (ALMA) Band 9 (~680 GHz) line data of the transitional disk Oph IRS 48, which was previously shown to have a large dust trap, to search for complex molecules in regions where planetesimals are forming. Results. We report the detection of the H2 CO 9(1, 8)-8(1, 7) line at 674 GHz, which is spatially resolved as a semi-ring at ~60 AU radius centered south from the star. The inferred H2 CO abundance is ~10-8 , derived by combining a physical disk model of the source with a non-LTE excitation calculation. Upper limits for CH3 OH lines in the same disk give an abundance ratio H2 CO/CH3 OH >0.3, which indicates that both ice formation and gas-phase routes play a role in the H2 CO production. Upper limits on the abundances of H13 CO+, CN and several other molecules in the disk were also derived and found to be consistent with full chemical models. Conclusions. The detection of the H2 CO line demonstrates the start of complex organic molecules in a planet-forming disk. Future ALMA observations are expected to reduce the abundance detection limits of other molecules by 1-2 orders of magnitude and test chemical models of organic molecules in (transitional) disks. [ABSTRACT FROM AUTHOR]- Published
- 2014
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25. The first ALMA view of IRAS 16293-2422.
- Author
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Pineda, J. E., Maury, A. J., Fuller, G. A., Testi, L., García-Appadoo, D., Peck, A. B., Villard, E., Corder, S. A., van Kempen, T. A., Turner, J. L., Tachihara, K., and Dent, W.
- Subjects
KINEMATICS ,SPECTRAL sensitivity ,P Cygni stars ,ASTRONOMICAL photometry ,SPEED ,ROTATIONAL motion ,HIGH resolution spectroscopy - Abstract
Aims. We focus on the kinematical properties of a proto-binary to study the infall and rotation of gas toward its two protostellar components. Methods. We present ALMA Science Verification observations with high-spectral resolution of IRAS 16293-2422 at 220.2 GHz. The wealth of molecular lines in this source and the very high spectral resolution offered by ALMA allow us to study the gas kinematics with unprecedented detail. Results. We present the first detection of an inverse P-Cygni profile toward source B in the three brightest lines. The line profiles are fitted with a simple two-layer model to derive an infall rate of 4.5 × 10
-5 M⊙ yr-1 . This infall detection would rule-out the previously suggested possibility that source B is a T Tauri star. A position velocity diagram for source A shows evidence of rotation with an axis close to the line-of-sight. [ABSTRACT FROM AUTHOR]- Published
- 2012
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26. Water in star-forming regions with Herschel (WISH) II. Evolution of 557 GHz 110-101 emission in low-mass protostars.
- Author
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Kristensen, L. E., van Dishoeck, E. F., Bergin, E. A., Visser, R., Yildiz, U. A., San Jose-Garcia, I., Jørgensen, J. K., Herczeg, G. J., Johnstone, D., Wampfler, S. F., Benz, A. O., Bruderer, S., Cabrit, S., Caselli, P., Doty, S. D., Harsono, D., Herpin, F., Hogerheijde, M. R., Karska, A., and van Kempen, T. A.
- Subjects
ASTRONOMICAL observations ,STAR formation ,SPECTRAL energy distribution ,PROTOSTARS ,BIPOLAR outflows (Astrophysics) - Abstract
Context. Water is a key tracer of dynamics and chemistry in low-mass star-forming regions, but spectrally resolved observations have so far been limited in sensitivity and angular resolution, and only data from the brightest low-mass protostars have been published. Aims. The first systematic survey of spectrally resolved water emission in 29 low-mass (L <40 Lʘ) protostellar objects is presented. The sources cover a range of luminosities and evolutionary states. The aim is to characterise the line profiles to distinguish physical components in the beam and examine how water emission changes with protostellar evolution. Methods. H
2 O was observed in the ground-slate 110 -101 transition at 557 GHz (Eup /kB -∼ 60K) as single-point observations with the Heterodyne Instrument for the Far-Infrared (HIFI) on Herschel in 29 deeply embedded Class 0 and I low-mass protostars. Complementary far-R and tub-mm continuum data (including PACS data from our programme) are used to constrain the spectral energy distribution (SED) of each source. H20 intensities are compared to inferred envelope properties, e.g., mass and density, outflow properties and CO 3-2 emission. Results. H2 O emission is detected in all objects except one (TMCIA). The line profiles are complex and consist of several kinematic components tracing different physical regions in each system. In particular, the profiles are typically dominated by a broad Gaussian emission feature, indicating that the bulk of the water emission arises in outflows, not in the quiescent envelope. Several sources show multiple shock components appearing in either emission or absorption, thus constraining the internal geometry of the system. Furthermore, the components include inverse P-Cygni profiles in seven sources (nix Class 0, one Class 1) indicative of infalling envelopes, and regular P-Cygni profiles in four sources (three Class 1, one Class 0) indicative of expanding envelopes. Molecular "bullets" moving at ≳50 km s-1 with respect to the source are detected in four Class 0 sources; three of these sources were not known to harbour bullets previously. In the outflow, the H2 O/CO abundance ratio an a function of velocity in nearly the name for all line wings, increasing from 10-3 at low velocities (<5 km s-1 ) to ≳ 10-1 at high velocities (>10 km s-1 ). The water abundance in the outer cold envelope in low, ≳10-10 . The different H2 O profile components show a clear evolutionary trend: in the younger Class 0 sources the emission in dominated by outflow components originating inside an infalling envelope. When large-scale infall diminishes during the Class I phase, the outflow weakens and H2 O emission all but disappears. [ABSTRACT FROM AUTHOR]- Published
- 2012
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27. Lactulose as a marker of intestinal barrier function in pigs after weaning.
- Author
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Wijtten, P. J. A., Verstijnen, J. J., van Kempen, T. A. T. G., Perdok, H. B., Gort, G., and Verstegen, M. W. A.
- Subjects
LACTULOSE ,PEROXIDASE ,SWINE ,INTESTINAL diseases ,BOWEL obstructions - Abstract
Intestinal barrier function in pigs after weaning is almost exclusively determined in terminal experiments with Using chambers. Alternatively, the recovery in urine of orally administered lactulose can be used to assess intestinal permeability in living animals. This experiment was designed to study the barrier function of the small intestine of pigs over time after weaning. The aim was to relate paracellular barrier function (measured by lactulose recovery in the urine) with macromolecular transport [measured by horseradish peroxidase (HRP) using Ussing chambers] and bacterial translocation to assess whether lactulose recovery is related to possible causes of infection and disease. Forty gonadectomized male pigs (6.7 ± 0.6 kg) were weaned (d 0) at a mean age of 19 d, fitted with urine collection bags, and individually housed. Pigs were dosed by oral gavage with a marker solution containing lactulose (disaccharide) and the monosaccharides L-rhamnose, 3-0rnethylglucose, and D-xylose at 2 h and at 4, 8, and 12 d after weaning. The recovery of sugars in the urine was determined over 18 h after each oral gavage. The day after each permeability test, the intestines of 10 pigs were dissected to determine bacterial translocation to the mesenteric lymph nodes and jejunal permeability for HRP in Ussing chambers. Recovery of L-rharnnose in urine was affected by feed intake and by the time after weaning (P < 0.05). Recovery of lactulose from the urine was greater (P 0.05) at 4, 8, and 12 d after weaning compared with the first day after weaning and was negatively correlated with feed intake (r = -0.63, P < 0.001). The mean translocation of aerobic bacteria to the mesenteric lymph nodes was greater at 5 and 13 d after weaning compared with d 1 (P < 0.05). Lactulose recovery showed no correlation with permeability for HRP nor with bacterial translocation (P> 0.05). Although both lactulose recovery and bacterial translocation increased over time after weaning, lactulose recovery did not correlate with the permeability for HRP nor bacterial translocation within a pig (P> 0.05). Therefore, we conclude that lactulose recovery in the urine of pigs after weaning is not associated with risk factors for infections. However, it appears to be possible to measure paracellular barrier function with orally administered lactulose in pigs shortly after weaning. Further studies will reveal whether this variable is relevant for the long-term performance or health of pigs after weaning. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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- View/download PDF
28. WISHES COMING TRUE: WATER IN LOW-MASS STAR-FORMING REGIONS WITH HERSCHEL.
- Author
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Kristensen, L. E., Visser, R., van Dishoeck, E. F., Yıldız, U. A., Herczeg, G. J., Doty, S., Jørgensen, J. K., van Kempen, T. A., Brinch, C., Wampfler, S., Bruderer, S., and Benz, A. O.
- Subjects
PLANETARY water ,STELLAR evolution ,ASTRONOMICAL observations ,PROTOSTARS - Abstract
Water is a key molecule for tracing physical and chemical processes in star-forming regions. The key program "Water in star-forming regions with Herschel" is observing several water transitions towards low-mass protostars with HIFI. Results regarding the 557 GHz transition of water are reported here showing that the line is surpris- ingly broad, and consists of several different velocity components. The bulk of the emission comes from shocks, where the abundance is increased by several orders of magnitude to ~10
-4 . The abundance of water in the outer envelope is determined to ~10-8 , whereas only an upper limit of 10-5 is derived for the inner, warm envelope. [ABSTRACT FROM AUTHOR]- Published
- 2011
- Full Text
- View/download PDF
29. Nutritional value for swine of extruded corn and corn fractions obtained after dry milling.
- Author
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Muley, N. S., Van Heugten, E., Moeser, A. J., Rausch, K. D., and Van Kempen, T. A. T. G.
- Subjects
ANIMAL nutrition ,CORN products ,SOYBEAN meal ,FORAGE plants ,EXTRUSION process ,AMINO acids ,SWINE ,PHOSPHORUS - Abstract
The experiment was designed to assess whether corn fractions or extrusion of corn can result in feed ingredients with a greater nutritional value than corn. Corn grain (8.0% CP, 0.21% P, 9.8% NDF) was processed by extrusion (82.8°C, 345 kPa steam pressure for 12 s) or by dry milling to derive fractions rich in germ (13.1% CP, 1.19% P, 17.2% NDF), hulls (8.1% CP, 0.27% P, 32.6% NDF), and endosperm, namely tails (6.6% CP, 0.07% P, 3.6% NDF) and throughs (7.4% CP, 0.15% P, 4.5% NDF). Relative recovery in each fraction was 16, 20, 44, and 20%, respectively. Ileal digestibility of DM, P, and amino acids was determined using diets containing 7.0% CP from soybean meal and 5.3% CP from one of the test products. To allow for determination of standardized ingredient, ileal digestibility, basal endogenous AA losses were determined using a protein-free diet (74.6% cornstarch and 18.7% sucrose). Soybean meal ileal digestibility was determined using a diet (12.3% CP) based on soybean meal (23.3%). Eight barrows (27 ± 2 kg) fitted with T-cannulas were fed 8 experimental diets (5-d adaptation and 2-d collection period) such that each diet was evaluated in at least 5 barrows. Relative to corn (77.9 ± 1.2%), ileal digestibility of DM was greater for extruded corn (82.5%; P = 0.02), tails (85.9%; P < 0.01), and throughs (85.0%; P < 0.01), but it was lower for hulls (62.2%; P < 0.01) and germ (51.1%; P < 0.01). For P, corn (41.6 ± 9.5%), throughs (47.2%), and hulls (57.3%) had similar ileal digestibility, but germ (7.9%) had lower ileal digestibility (P = 0.02) than corn; tails (27.6%) and extruded corn (23.5%) were not different from corn or germ but were lower than throughs and hulls. For total AA, corn (84.7 ± 2.4%), throughs (84.3%), and hulls (85.8%) had similar ileal digestibility, but germ (76.6%) had lower ileal digestibility (P < 0.01) than corn; tails (82.0%) and extruded corn (81.7%) were intermediate. In conclusion, germ and hulls have a low ileal DM digestibility; germ also has low AA and P digestibility. Extrusion improved the ileal DM digestibility of corn. To maximize the ileal digestibility, removal of germ and hull from corn or extrusion of corn may thus be of interest. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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30. Selecting soybean meal characteristics preferred for swine nutrition.
- Author
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Van Kempen, T. A. T. G., Van Heugten, E., Moeser, A. J., Muley, N. S., and Sewalt, V. J. H.
- Subjects
- *
ANIMAL nutrition , *SOYBEAN as feed , *SWINE , *ENVIRONMENTAL impact analysis , *ANIMAL feeding , *ANIMAL waste , *ANIMAL feeds , *RANGE management , *ANIMAL industry - Abstract
As environmental constraints become more important issues for the animal industry, selecting feed ingredients that yield good animal performance but also minimize environmental impact of animal production becomes critical. The objective of this research was to identify which compositional features would be desirable for soybean meal to maximize nutritional value and minimize animal waste. Eight soybean samples were selected from a database of 72, such that maximal variability for CP, NDF, and ADF content was obtained. Samples were subsequently processed into meal using standardized procedures. In Experiment 1, 8 cannulated pigs were used to determine ileal digestibility following a Latin square design. In Experiment 2, 5 of the samples were used in complete feeds and 10 pigs were used in a crossover Latin square design to determine the total tract digestibility, odorants in fresh and 5-d-old manure, and ammonia emission from manure. Differences up to 6% in ileal DM digestibility and 8% in ileal CP digestibility were observed. This difference was reduced to 1.1% for total tract DM digestibility and 4% for total tract CP digestibility. Differences in odorant concentration were 3-fold and for in vitro ammonia emission were 42%. The only compositional variable with a significant effect on digestibility was stachyose, which negatively affected ileal digestibility of DM (r = -0.80, P = 0.02) and energy (r = -0.73, P = 0.04). None of the compositional variables measured affected ileal CP digestibility. Ileal CP digestibility, however, was correlated with estimated CP fermentation in the large intestine (r = -0.86, P = 0.06) and with in vitro ammonia emission after 48h (r = -0.81, P = 0.09). In conclusion, nutritionally relevant variability exists in soy varieties. Low stachyose content is important for maximizing ileal energy digestibility of soy- bean meal. Although no compositional variable was identified that explained differences in ileal CP digestibility, maximizing ileal CP digestibility is of interest for maximizing the nutritional value of soybean meal and possibly for reducing ammonia and odor emissions. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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31. Technical note: Comparison of Raman, mid, and near infrared spectroscopy for predicting the amino acid content in animal meals.
- Author
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Qiao, Y. and van Kempen, T. A. T. G.
- Subjects
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FEED analysis , *AMINO acids in animal nutrition , *INFRARED spectroscopy , *NEAR infrared spectroscopy , *RAMAN spectroscopy , *ANIMAL nutrition - Abstract
The objective of this study was to compare three infrared spectroscopy techniques for routine evaluation of AA in animal meals. Animal meals (n = 54) with known AA contents were scanned with a near (NIBS), mid (FTIR), and Raman infrared spectrometer. For NIRS and Raman, samples were scanned "as is", whereas for FTIR, samples had to be finely ground before scanning to obtain reasonable spectra. Both FTIR and Raman data suffered from noise; for Raman, this prevented the development of calibrations. Using derivatized spectral data and a standardized outlier removal procedure, calibrations for nutritionally relevant AA could be developed that were equivalent for both NIRS and FTIR. The variation across AA tested explained (r²) by these calibrations was 70% for NIRS and 68 ± 3% for FTIR. Removing spectral data between 4,000 and 2,000 cm1 from the FTIR data improved calibrations (P = 0.09) and explained an average of 77% of the variation with prediction errors lower than obtained with NIBS (P < 0.01). However, FTIR calibrations based on the entire or the shortened spectrum contained fewer samples than did NIBS calibrations (41 and 39 vs. 48, respectively; P c 0.01) because more samples were removed as outliers. In conclusion, Raman did not yield acceptable spectra for animal meals. For FTIR, sample preparation was more time-consuming because the samples required grinding before analysis. Using the entire mid-infrared range, FTIB calibrations were com- parable to NIBS calibrations. Calibrations for FTIR were improved by eliminating wave numbers that exhibited more noise, resulting in prediction errors better than those for NIRS. Thus, FTIR has the potential to yield better calibrations for AA in animal meals than NIRS, but it requires greater care in sample preparation and scanning. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
32. Autosomal recessive form of hereditary motor and sensory neuropathy type I.
- Author
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Gabreëls-Festen, A. A.W.M., Gabreëls, F. J.M., Jennekens, F. G.I., Joosten, E. M.G., Kempen, T. W.Janssen-van, Gabreëls-Festen, A A, Gabreëls, F J, Jennekens, F G, Joosten, E M, and Janssen-van Kempen, T W
- Published
- 1992
- Full Text
- View/download PDF
33. Nucleotide supplementation enhances piglet performance.
- Author
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Tibbie, S., Köppel, P., and van Kempen, T.
- Subjects
PIGLETS ,ENERGY metabolism ,FEED quality ,ANALYSIS of variance ,DNA ,PLANT nurseries - Abstract
Nucleotides play several key roles in metabolism. They are the building blocks of RNA and DNA, intermediates in and regulators of energy metabolism, and co-factors for enzymes. The objective of this research was to determine if supplemental nucleotides enhanced performance of nursery piglets. Piglets (n=1280) weaned at 21 d of age were blocked into weight categories of 5, 6, and 7 kg and housed 12 per pen. Pens were assigned using a RCB design to diets containing 0 (control), 0.05%, 0.1%, 0.2%, and 0.4% nucleotides (Ascogen from Chemoforma). Piglets were fed high quality high zinc diets manufactured by SCA Iberica. Data were analyzed using analysis of variance, and treatment means were used to model the dose response using quadratic regression. ADG and G/F was significantly improved in all periods at 0.20% nucleotides. ADfiwas only significantly improved in period 1 (Table). The results of the dose-response analysis showed that nucleotide supplementation improved ADG by 18.7, 6.3, and 6.3% at an optimum dose of 0.23, 0.21, and 0.21%, in period 1, 2, and 3, respectively. In line with the results of the ANOVA, the feed intake response was less consistent, with an increase in feed intake in period 1 by 7.7% at a dose of 0.23%. G/F was improved by 10.4, 10.6, and 10.4 at doses of 0.25, 0.25, and 0.21% nucleotides in periods 1, 2, and 3, respectively. Overall, these data demonstrate that the optimum dose for nucleotides in order to optimize daily gain and gain/feed is 0.20 to 0.25%. The response for feed intake was variable and less strong. [ABSTRACT FROM AUTHOR]
- Published
- 2006
34. MODELING SOURCES OF GASEOUS EMISSIONS IN A PIG HOUSE WITH RECHARGE PIT.
- Author
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Kai, P., Kaspers, B., and Van Kempen, T.
- Subjects
- *
EMISSIONS (Air pollution) , *AMMONIA , *METHANE , *ODORS , *SWINE housing , *ANIMAL waste - Abstract
Ammonia, methane, and odor from a fully slatted pig housing facility equipped with a pit-recharge manure system were modeled with a view to quantify the sources of ammonia, methane, and odor. Emissions of ammonia, methane, and odor were measured during three weeks in two environmental chambers containing ten pigs. The chambers had fully slatted floors, and the pit was precharged with 120 L of water. After one week, the pigs were removed from the chambers, while measurements of emissions were continued for an additional two weeks. The trial was conducted in duplicate with pigs weighing 25 and 45 kg, respectively. Ammonia and methane were modeled to estimate concentrations in the presence (sigmoidal model) and upon removal of pigs (single pool exponential decay model). The combined model accounted for 89% of the variation in ammonia. The pit contributed 50% to 60% of the ammonia emission, while the slats contributed the remaining 40% to 50%. The mean ammonia emissions with pigs present were 26 and 17 g AU-1 d-1 with pigs weighing 25 and 45 kg, respectively. The model explained 98% of the observed variation in methane concentrations. The pigs and freshly excreted feces were the principal sources of methane, while the recharge pit did not emit significant amounts of methane. With pigs in the chambers, the mean methane emissions amounted to 14 g AU-1 d- irrespective of weight. Geometric mean odor emissions with pigs present were 6.0 OU AU-1 s-1 (95% confidence interval 4.2-8.6 OU AU-1 s- 1). Odor emissions were unaffected by the presence of pigs (p > 0.10). This indicates that manure, whether in the pit or on contaminated slats, is the main source of odor in pig houses, whereas the pigs themselves are of minor importance. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
35. PIH26 - A Comprehensive Survey Of Managed Care Organization (Mco) Medication Adherence Intervention Programs.
- Author
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Jones, C, Sullivan, I, Bayer, JC, Ng, K, Piracha, F, Boice, MH, Coutts, DJ, Mazlish, S, Nagarian, A, Alex, SP, Phani, S, Shah, K, Sheth, A, Sip, K, Van Kempen, T, and Basu-Roy, UK
- Subjects
- *
MANAGED care programs , *PATIENT compliance , *MEDICAL care costs , *HEALTH surveys , *PUBLIC health - Published
- 2015
- Full Text
- View/download PDF
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