Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

    Records 1 - 26 / 26

    • help
    • print

      Print search results

    • export

      Export search results

    Check title to add to marked list
    Effectiveness of deposit-refund systems for household waste in the Netherlands: Applying a partial equilibrium model
    Linderhof, Vincent ; Oosterhuis, Frans H. ; Beukering, Pieter J.H. Van; Bartelings, Heleen - \ 2019
    Journal of Environmental Management 232 (2019). - ISSN 0301-4797 - p. 842 - 850.
    Deposit-refund schemes (DRS) are basically a combination of two instruments: a tax on the purchase of a certain product, and a subsidy on the separate collection of the same product in its after-use stage. They can be efficient policy instruments to encourage reuse and recycling. However, empirical studies on impact of DRS systems on recycling rates are hardly done. In this paper, we applied the Fullerton-Wu model, a partial equilibrium model, to simulate the impact of introducing mandatory DRS for small electric appliances and
    batteries in the Netherlands. For small electric appliances, a deposit-refund rate of €5 to €15 per appliance would lead to an increase in the recycling rate (recycled appliances as a percentage of total amount of appliances disposed of) from 60.7% to 64.7% and 76.4% respectively. For batteries, a DRS would increase the recycling rate from 86.9% to between 87.2 and 89.2% depending on the deposit tax level ranging from €5 to €20 per kg and the price elasticities assumed (low and high). Obviously, the performance of DRS in terms of
    additional recycling is stronger in cases where current recycling rates are relatively low. Moreover, the pre-existence of an infrastructure for separate collection would make small white goods an interesting candidate for this instrument.
    Determinants of successful lifestyle change during a 6-month preconception lifestyle intervention in women with obesity and infertility
    Karsten, Matty D.A. ; Oers, Anne M. van; Groen, Henk ; Mutsaerts, Meike A.Q. ; Poppel, Mireille N.M. van; Geelen, Anouk ; Beek, Cornelieke van de; Painter, Rebecca C. ; Mol, Ben W.J. ; Roseboom, Tessa J. ; Hoek, Annemieke ; Burggraaff, J.M. ; Kuchenbecker, W.K.H. ; Perquin, D.A.M. ; Koks, C.A.M. ; Golde, R. van; Kaaijk, E.M. ; Schierbeek, J.M. ; Oosterhuis, G.J.E. ; Broekmans, F.J. ; Vogel, N.E.A. ; Lambalk, C.B. ; Veen, F. van der; Klijn, N.F. ; Mercelina, P.E.A.M. ; Kasteren, Y.M. van; Nap, A.W. ; Mulder, R.J.A.B. ; Gondrie, E.T.C.M. ; Bruin, J.P. de - \ 2019
    European Journal of Nutrition 58 (2019)6. - ISSN 1436-6207 - p. 2463 - 2475.
    Determinants - Lifestyle intervention - Obesity - Preconception

    Purpose: To identify demographic, (bio)physical, behavioral, and psychological determinants of successful lifestyle change and program completion by performing a secondary analysis of the intervention arm of a randomized-controlled trial, investigating a preconception lifestyle intervention. Methods: The 6-month lifestyle intervention consisted of dietary counseling, physical activity, and behavioral modification, and was aimed at 5–10% weight loss. We operationalized successful lifestyle change as successful weight loss (≥ 5% weight/BMI ≤ 29 kg/m2), weight loss in kilograms, a reduction in energy intake, and an increase in physical activity during the intervention program. We performed logistic and mixed-effect regression analyses to identify baseline factors that were associated with successful change or program completion. Results: Women with higher external eating behavior scores had higher odds of successful weight loss (OR 1.10, 95% CI 1.05–1.16). Women with the previous dietetic support lost 0.94 kg less during the intervention period (95% CI 0.01–1.87 kg). Women with higher self-efficacy reduced energy intake more than women with lower self-efficacy (p < 0.01). Women with an older partner had an increased energy intake (6 kcal/year older, 95% CI 3–13). A high stage of change towards physical activity was associated with a higher number of daily steps (p = 0.03). A high stage of change towards weight loss was associated with completion of the intervention (p = 0.04). Conclusions: Determinants of lifestyle change and program completion were: higher external eating behavior, not having received previous dietetic support, high stage of change. This knowledge can be used to identify women likely to benefit from lifestyle interventions and develop new interventions for women requiring alternative support. Trial registration: The LIFEstyle study was registered at the Dutch trial registry (NTR 1530;

    Feral goats shape the Caribbean drylands
    Holmgren, M. ; Coolen, Quirijn ; Debrot, A.O. ; Geurts, Kevin ; Metselaar, K. ; Oosterhuis, Henk-Jan ; Ende, Barry van den; Grinsven, Nikkie van; Hooft, W.F. van; Vergeer, Ascha - \ 2016
    - 1 p.
    DL-propargylglycine reduces blood pressure and renal injury but increases kidney weight in angiotensin-II infused rats
    Oosterhuis, Nynke R. ; Frenay, Anne Roos S. ; Wesseling, Sebas ; Snijder, Pauline M. ; Slaats, Gisela G. ; Yazdani, Saleh ; Fernandez, Bernadette O. ; Feelisch, Martin ; Giles, Rachel H. ; Verhaar, Marianne C. ; Joles, Jaap A. ; Goor, Harry Van - \ 2015
    Nitric oxide : biology and chemistry 49 (2015). - ISSN 1089-8603 - p. 56 - 66.
    Angiotensin-II - DL-Propargylglycine - Hydrogen sulfide - Hypertension - Kidney weight - Proteinuria

    Hydrogen sulfide (H2S), carbon monoxide (CO) and nitric oxide (NO) share signaling and vasorelaxant properties and are involved in proliferation and apoptosis. Inhibiting NO production or availability induces hypertension and proteinuria, which is prevented by concomitant blockade of the H2S producing enzyme cystathionine γ-lyase (CSE) by d,l-propargylglycine (PAG). We hypothesized that blocking H2S production ameliorates Angiotensin II (AngII)-induced hypertension and renal injury in a rodent model. Effects of concomitant administration of PAG or saline were therefore studied in healthy (CON) and AngII hypertensive rats. In CON rats, PAG did not affect systolic blood pressure (SBP), but slightly increased proteinuria. In AngII rats PAG reduced SBP, proteinuria and plasma creatinine (180 ± 12 vs. 211 ± 19 mmHg; 66 ± 35 vs. 346 ± 92 mg/24 h; 24 ± 6 vs. 47 ± 15 μmol/L, respectively; p <0.01). Unexpectedly, kidney to body weight ratio was increased in all groups by PAG (p <0.05). Renal injury induced by AngII was reduced by PAG (p <0.001). HO-1 gene expression was increased by PAG alone (p <0.05). PAG increased inner cortical tubular cell proliferation after 1 week and decreased outer cortical tubular nucleus number/field after 4 weeks. In vitro proximal tubular cell size increased after exposure to PAG. In summary, blocking H2S production with PAG reduced SBP and renal injury in AngII infused rats. Independent of the cardiovascular and renal effects, PAG increased HO-1 gene expression and kidney weight. PAG alone increased tubular cell size and proliferation in-vivo and in-vitro. Our results are indicative of a complex interplay of gasotransmitter signaling/action of mutually compensatory nature in the kidney.

    Human buccal epithelium acquires microbial hyporesponsiveness at birth, a role for secretory leukocyte protease inhibitor
    Menckeberg, C.L. ; Hol, J. ; Simons-Oosterhuis, Y. ; Raatgeep, H.R. ; Ruiter, L.F. de; Lindenbergh-Kortleve, D.J. ; Korteland-van Male, A.M. ; Aidy, S.F. El; Lierop, P.P.E. van; Kleerebezem, M. ; Groeneweg, M. ; Kraal, G. ; Elink-Schuurman, B.E. ; Jongste, J.C. de; Nieuwenhuis, E.E.S. ; Samsom, J.N. - \ 2015
    Gut 64 (2015). - ISSN 0017-5749 - p. 884 - 893.
    toll-like receptors - negative regulation - intestinal-mucosa - crohn-disease - responses - cells - tolerance - lipopolysaccharide - inflammation - mechanisms
    Objective Repetitive interaction with microbial stimuli renders epithelial cells (ECs) hyporesponsive to microbial stimulation. Previously, we have reported that buccal ECs from a subset of paediatric patients with Crohn's disease are not hyporesponsive and spontaneously released chemokines. We now aimed to identify kinetics and mechanisms of acquisition of hyporesponsiveness to microbial stimulation using primary human buccal epithelium. Design Buccal ECs collected directly after birth and in later stages of life were investigated. Chemokine release and regulatory signalling pathways were studied using primary buccal ECs and the buccal EC line TR146. Findings were extended to the intestinal mucosa using murine model systems. Results Directly after birth, primary human buccal ECs spontaneously produced the chemokine CXCL-8 and were responsive to microbial stimuli. Within the first weeks of life, these ECs attained hyporesponsiveness, associated with inactivation of the NF-¿B pathway and upregulation of the novel NF-¿B inhibitor SLPI but no other known NF-¿B inhibitors. SLPI protein was abundant in the cytoplasm and the nucleus of hyporesponsive buccal ECs. Knock-down of SLPI in TR146-buccal ECs induced loss of hyporesponsiveness with increased NF-¿B activation and subsequent chemokine release. This regulatory mechanism extended to the intestine, as colonisation of germfree mice elicited SLPI expression in small intestine and colon. Moreover, SLPI-deficient mice had increased chemokine expression in small intestinal and colonic ECs. Conclusions We identify SLPI as a new player in acquisition of microbial hyporesponsiveness by buccal and intestinal epithelium in the first weeks after microbial colonisation.
    Theory of Change thinking applied in MSPs
    Verhoosel, K.S. ; Leuvenink, A. ; Oosterhuis, T. ; Mostert, R.H. - \ 2012
    Wageningen : Wageningen UR Centre for Development Innovation - 7
    On Wednesday 19 September 2012, Centre for Development Innovation, Wageningen UR together with SNV organised a full-day seminar to discuss the application of the now widely used Theory of Change (ToC) thinking in Multi-Stakeholder Processes. This is a report of the seminar.
    Interaction of hesperetin glucuronide conjugates with human BCRP, MRP2 and MRP3 as detected in membrane vesicles of overexpressing baculovirus-infected Sf9 cells
    Brand, W. ; Oosterhuis, B. ; Krajcsi, P. ; Barron, D. ; Dionisi, F. ; Bladeren, P.J. van; Rietjens, I. ; Williamson, G. - \ 2011
    Biopharmaceutics and Drug Disposition 32 (2011)9. - ISSN 0142-2782 - p. 530 - 535.
    phase-ii metabolism - disposition - monolayers - hesperidin - bioavailability - transporters - absorption - flavanones - flavonoids - fruit
    The citrus flavonoid hesperetin (4'-methoxy-3',5,7-trihydroxyflavanone) is the aglycone of hesperidin, the major flavonoid present in sweet oranges. Hesperetin 7-O-glucuronide (H7G) and hesperetin 3'-O-glucuronide (H3'G) are the two most abundant metabolites of hesperetin in vivo. In this study, their interaction with specific ABC transporters, believed to play a role in the disposition and bioavailability of hesperetin, was studied using Sf9 membranes from cells overexpressing human BCRP (ABCG2), MRP2 (ABCC2) and MRP3 (ABCC3). Both H7G and H3'G were tested for their potential to activate and inhibit ATPase activity, and to inhibit vesicular transport by these transporters. Both H7G and H3'G demonstrated interaction with all tested ABC transporters, especially with BCRP and MRP3. An interesting difference between H7G and H3'G was seen with respect to the interaction with BCRP: H7G stimulated the ATPase activity of BCRP up to 76% of the maximal effect generated by the reference activator sulfasalazine, with an EC(50) of 0.45¿µ m, suggesting that H7G is a high affinity substrate of BCRP, whereas H3'G did not stimulate BCRP ATPase activity. Only moderate inhibition of BCRP ATPase activity at high H3'G concentrations was observed. This study provides information on the potential of hesperetin glucuronide conjugates to act as specific ABC transporter substrates or inhibitors and indicates that regio-specific glucuronidation could affect the disposition of hesperetin.
    Praktijkonderzoekers PPO Lelystad nog lang niet uitgezocht : Interview met Pierre Bakker en Henk Oosterhuis
    Buning, Stefan ; Oosterhuis, H.S. ; Bakker, P.W.V. - \ 2011
    Akker magazine 2011 (2011)1. - ISSN 1875-9688 - p. 36 - 39.
    proefbedrijven - landbouwkundig onderzoek - akkerbouw - vollegrondsgroenten - proeven op proefstations - proefstations - pilot farms - agricultural research - arable farming - field vegetables - station tests - experimental stations
    Van eenvoudig literatuuronderzoek tot het faciliteren van grote internationale evenementen. Het werk van de landbouwkundigen bij Praktijkonderzoek Plant & Omgeving in Lelystad is divers en steeds aan verandering onderhevig. "De factor mens wordt in het onderzoek steeds belangrijker", stellen de PPO-bedrijfsleiders Henk Oosterhuis en Pièrre Bakker.
    Effect of gaits and tempi on saddle force
    Oosterhuis, N.R. ; Cocq, P. de - \ 2010
    In: European Veterinary Conference Voorjaarsdagen, Amsterdam, the Netherlands, 22 - 24 April, 2010. - Amsterdam : - p. 330 - 331.
    Ontwikkeling van het prototype van SensiSpray in de gewassen aardappel en tulp
    Kempenaar, C. ; Oosterhuis, H.S. ; Lans, A.M. van der; Schans, D.A. van der; Stilma, E.S.C. ; Hendriks-Goossens, V.J.C. ; Verwijs, B.R. ; Wijk, C.A.P. van; Zande, J.C. van de - \ 2010
    Wageningen : Plant Research International (Nota / Plant Research International 667) - 32
    solanum tuberosum - aardappelen - tulipa - tulpen - fungiciden - loofvernietiging - spuiten - dosering - precisielandbouw - solanum tuberosum - potatoes - tulipa - tulips - fungicides - haulm destruction - spraying - dosage - precision agriculture
    Proefboerderij in de polder : Groenbemesters en grondbewerkingsvormen op De Broekemahoeve
    Oosterhuis, H.S. - \ 2010
    Ekoland 30 (2010)5. - ISSN 0926-9142 - p. 21 - 23.
    Een inspirerende Biologische Velddag : Innovaties in teelttechniek en afzetvormen
    Schlaman, G.L.H. ; Oosterhuis, H.S. - \ 2009
    Ekoland 29 (2009)9. - ISSN 0926-9142 - p. 24 - 26.
    biologische landbouw - agrarische bedrijfsvoering - innovaties - cultuurmethoden - demonstratiebedrijven, landbouw - publiciteit - akkerbouw - vollegrondsteelt - organic farming - farm management - innovations - cultural methods - demonstration farms - publicity - arable farming - outdoor cropping
    De Biologische Velddag werd dit jaar (2009) voor de vierde keer georganiseerd door Agrifirm, PPO-AGV, en het Centrum Biologische Landbouw. Hoogtepunt was het aanbod van innovatieve teelttechnieken en inspirerende vormen van afzetverbetering. Voorbeelden van teeltautomatisering werden uitgebreid toegelicht en in het veld getoond
    Effectiveness of unit-based pricing of waste in the Netherlands: applying a general equilibrium model
    Beukering, P.J.H. van; Bartelings, H. ; Linderhof, V.G.M. ; Oosterhuis, F.H. - \ 2009
    Waste Management 29 (2009)11. - ISSN 0956-053X - p. 2892 - 2901.
    household waste - collection
    Differential and variable rates (DVR) in waste collection charging give a price incentive to households to reduce their waste and increase recycling. International empirical evidence confirms the effectiveness of DVR schemes, with limited unwanted side effects. In the Netherlands, currently some 20% of the population is charged at DVR. This is less than in several other countries. Taking into account differences between types of households and dwellings, this study analyses various scenarios for extended use of DVR in the Netherlands. The analysis shows that further penetration of DVR is a cost-effective instrument for waste reduction and more recycling. Moreover, DVR can itself be seen as a necessary condition for the successful implementation of other economic instruments, such as waste taxes. It is therefore recommended to stimulate municipalities to adopt DVR schemes in the Netherlands, accompanied by the provision of adequate facilities for waste separation by households. Before introducing DVR in 'very strongly urbanized' municipalities (i.e. the 12 largest cities in the Netherlands) a pilot experiment in one of them might be useful to test the behavioral response in this category. (C) 2009 Elsevier Ltd. All rights reserved.
    Economic instruments and waste policies in the Netherlands: Inventory and options for extended use
    Oosterhuis, F. ; Bartelings, H. ; Linderhof, V.G.M. ; Beukering, P.J.M. van - \ 2009
    Amsterdam : IVM Instituut voor Milieuvraagstukken (Report / Institute for environmental studies R-09/01) - 133
    milieubeleid - afvalbeheer - economische impact - economisch beleid - heffingen - fiscaal beleid - internationale vergelijkingen - maatregelen - economische aspecten - environmental policy - waste management - economic impact - economic policy - levies - fiscal policy - international comparisons - measures - economic aspects
    In recent years, the interest in the use of economic instruments in environmental policy has been growing, reflecting increasing awareness of their potential cost-effectiveness as well as the need to diversify the ‘policy toolbox’. Waste policy is no exception to this tendency. The present study explores the opportunities for extended use of economic instruments for waste policy in the Netherlands, focusing on waste from households and the trade, services and government sector
    Gangbare en biologische telers vinden elkaar in de bodem : praktijkdag bodemkwaliteit 'Bodem 2008' op 3 juli 2008 in Lelystad
    PPO Akkerbouw, Groene Ruimte en Vollegrondsgroente, ; Jansma, J.E. - \ 2008
    Nieuwe oogst / Magazine gewas 4 (2008)10. - ISSN 1871-093X - p. 6 - 7.
    biologische landbouw - cultuurmethoden - duurzaamheid (sustainability) - grondanalyse - bodembeheer - mestbehoeftebepaling - vollegrondsgroenten - vollegrondsteelt - organic farming - cultural methods - sustainability - soil analysis - soil management - fertilizer requirement determination - field vegetables - outdoor cropping
    De bodem staat centraal op de praktijkdag 'Bodem 2008', die PPO-AGV, DLV Plant, Agrifirm en het Centrum Biologische Landbouw houden op 3 juli 2008. Hiermee willen ze ondernemers stimuleren in de bodem te kijken, zegt Henk Oosterhuis, bedrijfsleider bij PPO proefbedrijf Prof. Broekemahoeve. "Want de bodem vertelt méér over de groei van het gewas dan wat je op het veld kunt zien"
    Niet meer roeren in grond dan nodig
    Oosterhuis, H.S. - \ 2008
    BioKennis nieuws (2008).
    Bodem 2008 / Bio velddag 2008
    Jansma, J.E. ; Oosterhuis, H.S. ; Spigt, R.M. ; Olijve, A.J. - \ 2008
    Assessment of technological options and economical feasibility for cyanophycin biopolymer and high-value amino acid production
    Mooibroek, H. ; Oosterhuis, N. ; Giuseppin, M.L.F. ; Toonen, M.A.J. ; Franssen, H.G.J.M. ; Scott, E.L. ; Sanders, J.P.M. ; Steinbuchel, A. - \ 2007
    Applied Microbiology and Biotechnology 77 (2007)2. - ISSN 0175-7598 - p. 257 - 267.
    molecular characterization - anabaena-cylindrica - ralstonia-eutropha - escherichia-coli - aspartic-acid - filamentous cyanobacterium - recombinant strains - degrading bacteria - pseudomonas-putida - transgenic plants
    Major transitions can be expected within the next few decades aiming at the reduction of pollution and global warming and at energy saving measures. For these purposes, new sustainable biorefinery concepts will be needed that will replace the traditional mineral oil-based synthesis of specialty and bulk chemicals. An important group of these chemicals are those that comprise N-functionalities. Many plant components contained in biomass rest or waste stream fractions contain these N-functionalities in proteins and free amino acids that can be used as starting materials for the synthesis of biopolymers and chemicals. This paper describes the economic and technological feasibility for cyanophycin production by fermentation of the potato waste stream Protamylasse¿ or directly in plants and its subsequent conversion to a number of N-containing bulk chemicals.
    De Smaak van Morgen : Systeeminnovatie van toekomst naar heden
    Jansma, J.E. ; Olijve, A.J. ; Oosterhuis, H.S. - \ 2004
    innovaties - bedrijfssystemen - innovations - farming systems
    Poster over het project de smaak van morgen
    De Smaak van Morgen : de praktijk
    Jansma, J.E. ; Olijve, A.J. ; Oosterhuis, H.S. - \ 2004
    bedrijfssystemen - farming systems
    Dat houdt het project de smaak van morgen in? Een poster met uitleg.
    Naar een reproductiemeetnet voor broedvogels in de Waddenzee
    Oosterhuis, R. ; Dijksen, L. ; Ens, B.J. ; Foppen, R. ; Jong, M.L. de; Kats, R.J.M. van; Turnhout, C. van; Willems, F. - \ 2004
    Wageningen : Alterra / SOVON (Alterra rapport 944) - 48
    vogels - broedvogels - populatiedynamica - monitoring - nederlandse waddeneilanden - birds - breeding birds - population dynamics - monitoring - dutch wadden islands
    Als onderdeel van het door het ministerie van LNV gefinancierde onderzoek “Voedselaanbod voor Vogels” (bestek 5a) is er door SOVON in samenwerking met Alterra een pilotstudy uitgevoerd naar de mogelijkheden om een reproductiemeetnet in het Waddengebied op te zetten. Die studie had betrekking op zes soorten die algemeen voorkomen in het Nederlandse Waddengebied (Eider, Scholekster, Kluut, Kokmeeuw, Zilvermeeuw en Visdief). Deze soorten zijn aangewezen op verschillende belangrijke voedselbronnen in de Waddenzee: vis, schelpdieren, garnalen of bodemdieren als Wadpier en Zeeduizendpoot). Voor de zes soorten is beschreven welke informatie over de reproductie kan worden verzameld en welke methoden hiervoor gebruikt kunnen worden.
    Rondom boerenkaas
    Haven, T. van der; Oosterhuis, H. - \ 1999
    Lelystad : Praktijkonderzoek Rundvee, Schapen en Paarden (Themaboek 40) - 240 p.
    De wereld van de Boerenkaas is volop in ontwikkeling. Vooral de omgeving van de Boerenkaas, zoals wetgeving, markt en de maatschappelijke verhoudingen, is veranderd, maar ook de omstandigheden op de kaasboerderij zijn niet dezelfde gebleven. Anders dan de titel van dit boek doet vermoeden is de inhoud vooral gericht op het productieproces zelf. Daardoor konden aanpassingen van de inhoud beperkt blijven, wat overigens niet inhoud dat deze tweede druk een kopie is van zijn voorganger. Nieuwe onderwerpen, als standaardiseren en pasteuriseren zijn toegevoegd, aspecten van wetgeving zijn weggelaten.
    The influence of torque and velocity on erector spinae muscle fatigue and its relationship to changes of electromyogram spectrum density
    Dieën, J. van; Böke, B. ; Oosterhuis, W. ; Toussaint, H.M. - \ 1996
    European Journal of Applied Physiology 72 (1996). - ISSN 1439-6319 - p. 310 - 315.
    Toekomst voor het populierenlandschap?
    Oosterhuis, J.W. ; Sanden, J. van der - \ 1987
    Populier 24 (1987)1. - ISSN 0166-7491 - p. 9 - 11.
    Architectural approach to analysis of North American temperate deciduous forests
    Oosterhuis, L. ; Oldeman, R.A.A. ; Sharik, T.L. - \ 1982
    Canadian Journal of Forest Research 12 (1982). - ISSN 0045-5067 - p. 835 - 847.
    centraal-amerika - loofverliezende bossen - bosbouw - noord-amerika - opstandsontwikkeling - opstandsstructuur - gematigde klimaatzones - central america - deciduous forests - forestry - north america - stand development - stand structure - temperate zones
    Rapport betreffende het onderzoek naar de bodemgesteldheid van het typebedrijf W.T. Oosterhuis (Roodeschool)
    Smet, L.A.H. de; Bakker, H. de - \ 1950
    Wageningen : STIBOKA - 12
    kaarten - bodemkarteringen - nederland - groningen - maps - soil surveys - netherlands - groningen
    Check title to add to marked list

    Show 20 50 100 records per page

    Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.