On inter- or transdisciplinarity: inherent handicaps and some solutions?

We live in the aftermath of extreme specialization in scientific branches and witness the revival of integration. Also, our image and credentials in society have sometimes dropped, whether we like it or not. The main reason is that society has to cope with complex problems and does not accept partial, e.g. technocratic, solutions from specialists for problems that require a broader scope, a more balanced decision-making process rooted in the desire to create sustainable solutions. Together with the division of science in disciplines and sub-disciplines the organization of visions on reality (in paradigms), research activities (programs) and researchers (in disciplinary communities) seem to have become conservative in its own. Centripetal forces dominate. Reasons are bureaucratic sluggishness and territorial behaviour, the prestige of specialists among colleagues and in the public opinion, psychological characteristics of researchers and the amount of time, money, energy needed for interdisciplinary ventures. Last but not least: integration is less easy than sometimes thought. It requires more abilities than analytical brightness and relies heavily on other skills and knowledge. New theories, concepts and methods are required. Some elaboration is given below, as well as suggestions to overcome or minimize some of the handicap

Voorstudies natuurverkenningen 2002 : onderdeel internationaal

Internationale waarden van de Nederlandse natuur: een analyse voor het Natuurplanburea

Nederlandse kustduinen : geomorfologie en bodems

This report forms part of an interdisciplinary survey on landscape ecology of the Dutch coastal dunes. Other subjects are dealt with in 'Geohydrology' (Bakker, 1981), 'Geobotany' (Van Zadelhoff, 1981) and 'Landscape ecology' (Bakker et al., 1981). The subjects in these reports have been selected primarily for ecological significance. Within this ecological frame, most attention was paid to the dune slacks, being the most vulnerable and threatened dune habitat in the Netherlands.This report describes climatic history especially in the Middle Ages and later centuries (Chap. 2), coastal development (Chap. 3), geology (Chap. 4); human influences on relief and soil (Chap. 5), being 'decision variables' for geomorphological and pedological features. An explanation of dune-forming mechanisms is followed by a classification of dune forms (Chap. 6). Also a brief description of the Dutch coastal dunes is given in relation to the geomorphological map (scale 1:100 000, App. IV). Further some attention is given to the ecological features of dune slacks, and also some remarks are made on nature management. Chapter 7 is focused on the sudden origin of the 'Younger Dunes' in the Netherlands and the existence of three major phases in their development. The major part of the dunes proved to result from secondary dune-forming processes, for which the most probable cause is coastal erosion. There seems to be a cause-effect relation between climatic changes, phases of coastal erosion and phases of secondary duneforming. Chapter 8 gives an outline of the main soil forming processes like the development of a humus-layer and leaching of compounds like carbonates as an introduction on the ecologically important moisture and nutrient conditions in dune soils. Special attention is given to the influence of pH and moisture regime as well as to the effect of human activities.<p/

Klimaatverandering in de 21ste eeuw: consequenties voor het natuurbeleid

Als achtergrondstudie bij de Natuurbalans 2003 is literatuuronderzoek gedaan naar al te signaleren effecten van klimaatsveranderingen op de natuur, de te verwachten aard en omvang van toe-komstige klimaatveranderingen en de indirecte en directe effecten op ecosystemen en soorten. Op basis daarvan zijn aanbevelingen gedaan om de veerkracht en adaptatie van ecosystemen en populaties te versterken via ruimtelijke - en beheersstrategieën. Aanbevolen is de strategie van de ecologische hoofdstructuur volop te benutten en te versterken.Internationnale perspectieven zijn noodzakelijk. Ook zullen natuurdoelen moeten worden bijgesteld. Meekoppelen met maatregelen voor een aangepast kust- en waterbeheer lijkt mogelijk. De bijdrage van natuurontwikkeling aan koolstofvastlegging kan slechts marginaal zijn

The clinical significance of epidermal growth factor receptor (egf-r) in human breast cancer: A review on 5232 patients

Epidermal growth factor (EGF) is a 53-aminoacid polypeptide (mol wt 6.045 K) that can influence proliferation and differentiation of a wide variety of cells (1–6). EGF as well as transforming growth factor-α (TGF-α), both of which can activate EGF receptor (EGF-R), are probably produced locally in many tissues as local growth factors rather than as systemic hormones. There is evidence that EGF plays a role in carcinogenesis and that the EGF-stimulated growth regulatory system (apart from that of benign cells) is also involved in proliferation of malignant cells (3). Cellular events are induced by EGF via its cell membrane receptor (EGF-R). The EGF-R is a 170 K glycoprotein that can be divided into an extracellular domain binding EGF or TGF-α, a short transmembrane domain, and an intracellular domain carrying tyrosine kinase activity (7). This intracellular domain shows close sequence homology with the c-erbB-2 and with neu (8), the rat homolog of c-erbB-2 oncogene. Increased expression of the EGF-R gene has been found in a variety of tumors, generally indicating a more aggressive behavior of cancers compared to those with low or normal expression (9–10) although this association is not invariant (11). EGF-R has been identified by several methods including radioligand binding assays, autoradiography, immunocytohistochemistry, immunoenzymatic assays, and measurement of EGF-R transcripts

Het landschap bestudeer je van groot naar klein, niet andersom; interview met Ies (prof.dr.ir. I.S.) Zonneveld

Als eerste bijdrage binnen dit themanummer over het werk van Zonneveld en (daaraan gekoppeld) het fenomeen deltalandschap: een uitgebreid interview met de 82 jarige landschapsecoloog (landecoloog, zoals hijzelf zegt). Het betreft zaken als: wat blijft er over van het agrarisch landschap; mag natuur zelfredzaam zijn of moet het beheerd worden; is er herstel mogelijk van het watergetijdegebied, met het open gaan van de Haringvlietsluizen; is er een effect van reorganisaties bij overheidsdiensten op natuur en landschap; hoe verhouden modellen en GIS zich tot het vakgebied; wat is de plaats van de Nederlandse landschapsecologie in internationaal perspectie

Thymidine kinase and thymidylate synthase in advanced breast cancer: response to tamoxifen and chemotherapy

Thymidylate synthase (TS) is a crucial target for 5-fluorouracil (5-FU) in the de novo pathway of pyrimidine synthesis, which is necessary for DNA synthesis. Thymidine kinase (TK) plays a key role in the complementary or alternative salvage pathway of pyrimidine synthesis in acute or pathological tissue stress. In the present study, the activity levels of TS and TK were determined in 257 primary breast tumors of patients who received tamoxifen as first-line systemic therapy after diagnosis of advanced disease. In 155 (60%) responding patients, the median response duration was 23 months for tumors with low TK activity, 15 months for tumors with intermediate TK activity, and 13 months for tumors with high TK activity (P = 0.003). In Cox multivariate analysis corrected for classical predictive factors including estrogen receptor and progesterone receptor, patients with intermediate and high levels of TK activity in their tumors showed a rapid disease progression (P = 0.0002) and an early death (P = 0.002) after start of tamoxifen treatment. Tumor TS activity levels were not significantly associated with the efficacy of tamoxifen treatment. In 121 patients who became resistant to tamoxifen or additional endocrine treatments and who received 5-FU-containing polychemotherapy, tumor TK activity was not significantly related to the efficacy of chemotherapy. Of the 13 patients with low tumor TS activity, only 1 (8%) responded favorably, whereas 46% (43 of 93) of those with intermediate and 73% (11 of 15) of those with high TS activity responded (P = 0.001). In Cox multivariate regression analysis in which TS was the only significant variable, intermediate and high TS activities were associated with a slow disease progression (P = 0.005) and prolonged survival (P = 0.016) on chemotherapy. In conclusion, for patients with recurrent breast cancer, high tumor TK activity is a significant marker of poor clinical outcome on tamoxifen therapy. Elevated tumor TS activity predicts a favorable outcome for 5-FU-containing polychemotherapy when applied after tumor progression on endocrine therapy