1,154 research outputs found
Hundred years of history and the future of the Foundation 'Willie Commelin Scholten Phytopathological Laboratory'
The past
More than a century ago, on December 18th, 1894, the
Foundation 'Willie Commelin Scholten Phytopathological
Laboratory', in short 'WCS-Foundation'
(WCS) , was established in Amsterdam. It was one
of the first institutes in the world dedicated to scientific
research and higher education in plant pathology.
The finances were by courtesy of Mr C.W.R.
Scholten and Mrs H.H. Scholten née Commelin, in
commemoration of their late son Willie, who had
shown himself highly interested in plant pathology
when studying botany under the supervision of Prof.
Dr Hugo de Vries, one of the founders of the WCS.
The families Scholten and Commelin both were wellknown
in the Amsterdam community for many centuries.
Johannes Commelin, a botanist who lived from
1629 to 1692, was Director of the Amsterdam Botanical
Gardens. In 1920, the WCS-laboratory moved to
the town of Baarn where it could use the field facilities
of the Botanical Gardens of the UtrechtUniversity.
In the course of time, the responsibilities for education
and research in plant pathology in Baarn were assigned
to the University of Utrecht, the University of Amsterdam
and the Free University at Amsterdam (Kerling,
1966; 1969).
As part of the general cut-backs in higher education,
the Free University withdrew in 1987 and the
boards of the Universities of Amsterdam and Utrecht
decided in 1988 to transfer their Department of plant
pathology from Baarn. As a result, the Department
was split and moved to the Faculties of Biology at
the University campuses at Amsterdam and Utrecht,
respectively. In June 1991, the facilities of the Willie
Commelin Scholten Phytopathological Laboratory at Baarn were closed. TheWCS-Foundation carrying the
same name, however, set a new course to continue
her objectives of promoting research and education in
plant pathology, as will be discussed later.
For more than 100 years, the WCS-Foundation
greatly influenced the development of plant pathology
and mycology in the Netherlands. On the initiative
of the first director, Prof. Dr J. Ritzema Bos,
the Plant Protection Service was founded in 1899, and
under his directorship located in the Willie Commelin
Scholten Phytopathological Laboratory in Amsterdam.
His research was application-oriented and finally
resulted in his nomination as Director of the newly
founded 'Institute of Phytopathology' at Wageningen.
Ritzema Bos took his 'Plant Protection Service', the
Netherlands Society of Plant Pathology and his 'Tijdschrift
over Plantenziekten' with him to Wageningen.
This journal later became The Netherlands Journal of
Plant Pathology and since 1994 is being continued as
the European Journal of Plant Pathology, published in
co-operation with the European Foundation for Plant
Pathology. Ritzema Bos was succeeded by Johanna
Westerdijk as the new director of the WCS-Laboratory
in 1906
Unravelling of Waste in a Touristic Area of Pangandaran From Neglecting Towards Embracing Informal Waste Management Practices, West Java, Indonesia
Increased attention for sustainable waste management practices has in Indonesia resulted in legislation that seeks participation and self-regulation amongst people in urban and rural areas. However districts are trying to meet the expectations of the national government, implementing Westernized-recycling systems. We demonstrate that these top-down waste management practices as well as the current approach towardsscavenging systemsas being problematic and undesirable, will not lead to effective waste management. Using a holistic approach we explore the subjectivity of waste and alternating perceptions of these objects in both formal and informal waste management practices.Moreover this article considers the functioning of informal waste management systems to be dynamic and profitable. Within the context of a touristic area that can\u27t keep up with the increasing amount of solid waste, this article advocates a highly potential informal waste management practices that are systematically overlooked
Electromagnetic form factors of the (rho) meson in light cone QCD sum rules
We investigate the electromagnetic form factors of the (rho) meson in light
cone QCD sum rules. We find that the ratio of the magnetic and charge form
factors is larger than two at all values of Q^2, (Q^2 >= 0.5 GeV^2). The values
of the individual form factors at fixed values of Q^2 predicted by the light
cone QCD sum rules are quite different compared to the results of other
approaches. These results can be checked in future, when more precise data on
(rho) meson form factors is available.Comment: 12 pages, 6 figures, LaTeX formatte
Interference effects in the photorecombination of argonlike Sc3+ ions: Storage-ring experiment and theory
Absolute total electron-ion recombination rate coefficients of argonlike
Sc3+(3s2 3p6) ions have been measured for relative energies between electrons
and ions ranging from 0 to 45 eV. This energy range comprises all dielectronic
recombination resonances attached to 3p -> 3d and 3p -> 4s excitations. A broad
resonance with an experimental width of 0.89 +- 0.07 eV due to the 3p5 3d2 2F
intermediate state is found at 12.31 +- 0.03 eV with a small experimental
evidence for an asymmetric line shape. From R-Matrix and perturbative
calculations we infer that the asymmetric line shape may not only be due to
quantum mechanical interference between direct and resonant recombination
channels as predicted by Gorczyca et al. [Phys. Rev. A 56, 4742 (1997)], but
may partly also be due to the interaction with an adjacent overlapping DR
resonance of the same symmetry. The overall agreement between theory and
experiment is poor. Differences between our experimental and our theoretical
resonance positions are as large as 1.4 eV. This illustrates the difficulty to
accurately describe the structure of an atomic system with an open 3d-shell
with state-of-the-art theoretical methods. Furthermore, we find that a
relativistic theoretical treatment of the system under study is mandatory since
the existence of experimentally observed strong 3p5 3d2 2D and 3p5 3d 4s 2D
resonances can only be explained when calculations beyond LS-coupling are
carried out.Comment: 11 pages, 7 figures, 3 tables, Phys. Rev. A (in print), see also:
http://www.strz.uni-giessen.de/~k
Photoionization of tungsten ions: experiment and theory for W
Experimental and theoretical results are reported for single-photon single
ionization of the tungsten ion W. Absolute cross sections have been
measured employing the photon-ion merged-beams setup at the Advanced Light
Source in Berkeley. Detailed photon-energy scans were performed at 200~meV
bandwidth in the 40 -- 105~eV range. Theoretical results have been obtained
from a Dirac-Coulomb R-matrix approach employing basis sets of 730 levels for
the photoionization of W. Calculations were carried out for the
, =2, ground level and the
associated fine-structure levels with =3 and 4 for the W ions. In
addition, cross sections have been calculated for the metastable levels
. Very satisfying agreement of theory and experiment is
found for the photoionization cross section of W which is remarkable
given the complexity of the electronic structure of tungsten ions in low charge
states.Comment: 15 pages, 3 figures, to appear in the Journal of Physics B: Atomic,
Molecular and Optical Physic
Playing Charades in the fMRI: Are Mirror and/or Mentalizing Areas Involved in Gestural Communication?
Communication is an important aspect of human life, allowing us to powerfully coordinate our behaviour with that of others. Boiled down to its mere essentials, communication entails transferring a mental content from one brain to another. Spoken language obviously plays an important role in communication between human individuals. Manual gestures however often aid the semantic interpretation of the spoken message, and gestures may have played a central role in the earlier evolution of communication. Here we used the social game of charades to investigate the neural basis of gestural communication by having participants produce and interpret meaningful gestures while their brain activity was measured using functional magnetic resonance imaging. While participants decoded observed gestures, the putative mirror neuron system (pMNS: premotor, parietal and posterior mid-temporal cortex), associated with motor simulation, and the temporo-parietal junction (TPJ), associated with mentalizing and agency attribution, were significantly recruited. Of these areas only the pMNS was recruited during the production of gestures. This suggests that gestural communication relies on a combination of simulation and, during decoding, mentalizing/agency attribution brain areas. Comparing the decoding of gestures with a condition in which participants viewed the same gestures with an instruction not to interpret the gestures showed that although parts of the pMNS responded more strongly during active decoding, most of the pMNS and the TPJ did not show such significant task effects. This suggests that the mere observation of gestures recruits most of the system involved in voluntary interpretation
Single-photon single ionization of W ions: experiment and theory
Experimental and theoretical results are reported for photoionization of
Ta-like (W) tungsten ions. Absolute cross sections were measured in the
energy range 16 to 245 eV employing the photon-ion merged-beam setup at the
Advanced Light Source in Berkeley. Detailed photon-energy scans at 100 meV
bandwidth were performed in the 16 to 108 eV range. In addition, the cross
section was scanned at 50 meV resolution in regions where fine resonance
structures could be observed. Theoretical results were obtained from a
Dirac-Coulomb R-matrix approach. Photoionization cross section calculations
were performed for singly ionized atomic tungsten ions in their , =1/2, ground level and the associated
excited metastable levels with =3/2, 5/2, 7/2 and 9/2. Since the ion beams
used in the experiments must be expected to contain long-lived excited states
also from excited configurations, additional cross-section calculations were
performed for the second-lowest term, 5d^5 \; ^6{\rm S}_{J}, =5/2, and for
the F term, 5d^3 6s^2 \; ^4{\rm F}_{J}, with = 3/2, 5/2, 7/2 and 9/2.
Given the complexity of the electronic structure of W the calculations
reproduce the main features of the experimental cross section quite well.Comment: 23 pages, 7 figures, 1 table: Accepted for publication in J. Phys. B:
At. Mol. & Opt. Phy
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