132 research outputs found
Using knowledge for decision-making purposes
Abstract:
Policy-related research in general, and Impact Assessments in particular, are too loosely
connected to decision-making processes. The result is often sub-optimal or even undesirable, as
one of two situations arises: 1) much research is done; however, those with the real power to
make decisions do not make use of all of the resulting information, or 2) advocates of contrary
opinions struggle with each other, using policy-related research as ammunition. To avoid these
unwanted situations, the connection between the world of knowledge and the world of decisionmaking
should be carefully constructed, by connecting the process of decision-making to the
academic research and carefully developing research goals in response to the demands of
decision-makers. By making these connections in a stepwise manner, knowledge may generate
new insights and views for involved decision-makers and stakeholders, thus changing
perceptions and problem definitions. In this way, these actors learn about the possibilities of
several alternatives as well as each other’s perceptions, and thus can make educated decisions
leading to the most desirable and socially acceptable solution. The way this proposed method
works is illustrated using two cases in The Netherlands: the project “Mainport Rotterdam” (the
enlargement of the port of Rotterdam), the project “A fifth runway for Amsterdam Airport
(Schiphol)”
Pulmonary hypertension after transjugular intrahepatic portosystemic shunt (TIPS)
We reported the case of a patient in whom severe, and ultimately fatal,
pulmonary hypertension developed 1.5 yrs after transjugular intrahepatic
portosystemic shunt (TIPS). Pulmonary artery pressures were not affected
by 100% oxygen, prostacyclin or nifedipine. Postmortem examinations showed
pulmonary and vascular abnormalities typical of pulmonary hypertension.
Pulmonary artery pressures should be measured in each patient with
otherwise not readily explained dyspnoea following transjugular
intrahepatic portosystemic shunt
Spin observables in deuteron-proton radiative capture at intermediate energies
A radiative deuteron-proton capture experiment was carried out at KVI using
polarized-deuteron beams at incident energies of 55, 66.5, and 90 MeV/nucleon.
Vector and tensor-analyzing powers were obtained for a large angular range. The
results are interpreted with the help of Faddeev calculations, which are based
on modern two- and three-nucleon potentials. Our data are described well by the
calculations, and disagree significantly with the observed tensor anomaly at
RCNP.Comment: 10 pages, 4 figures, submitted to PL
Возможность прогнозирования клеточного типа увеальных меланом без использования инвазивных методов диагностики
Резюме. С помощью дискриминантного анализа установлена возможность определения клеточного типа меланомы увеального тракта в процессе проведения комбинированного (фотокоагуляция + брахитерапия) лечения. Разработана высокозначимая (l = 0,08; р = 0,002) дискриминантная модель, включающая ряд клинических (степень пигментации, пол, скорость роста меланомы) и иммунологических (количество Т- и В-лимфоцитов, процент Т-хелперов и др.) показателей. Особое место в модели занимают признаки, в наибольшей степени отражающие биологические особенности увеальных меланом различного клеточного состава, а именно — скорость изменения размера опухоли в процессе лечения и изменение показателей клеточного иммунитета.
Ключевые слова: увеальная меланома, клеточный тип, клинико-морфологические, иммунологические показатели, дискриминантный анализ.Summary. Application of the discriminant analysis shows that it is possible to define the cell type of melanoma of uveal tract of the eye in the process of combined (photocoagulation + brachytherapy) treatment. A highly reliable (l= 0,08; р = 0,002) discriminant model was elaborated, involving a number of both clinical (pigmentation level, gender, melanoma growth rate) and immunological (number of T and B lymphocytes, T helper rate, etc.) indicators. In this model, especially important are those traits that most pronouncedly reflect the biological peculiarities of uveal melanomas of various cellular compositions, namely — the pace of tumor size growth in the process of treatment and changes in cell immunity indicators.
Key Words: uveal melanoma, cell type, clinical and morphological, immunological indicators, discriminant analysis
Proton-deuteron radiative capture cross sections at intermediate energies
Differential cross sections of the reaction have been
measured at deuteron laboratory energies of 110, 133 and 180 MeV. The data were
obtained with a coincidence setup measuring both the outgoing He and the
photon. The data are compared with modern calculations including all possible
meson-exchange currents and two- and three- nucleon forces in the potential.
The data clearly show a preference for one of the models, although the shape of
the angular distribution cannot be reproduced by any of the presented models.Comment: 6 pages, 6 figures, accepted for publication in EPJ
Systematic investigation of three-nucleon force effects in elastic scattering of polarized protons from deuterons at intermediate energies
The question, whether the high-quality nucleon-nucleon potentials can successfully describe the three-nucleon system, and to what extent three-nucleon forces (3NFs) play a role, has become very important in nuclear few-body physics. One kinematic region where effects because of 3NFs show up is in the minimum of the differential cross section of elastic nucleon-deuteron scattering. Another observable, which could give an indication about the contribution of the spin to 3NFs, is the vector analyzing power. To investigate the importance of 3NFs systematically over a broad range of intermediate energies, both observables of elastic proton-deuteron scattering have been measured at proton bombarding energies of 108, 120, 135, 150, 170, and 190 MeV, covering an angular range in the center-of-mass system between 30° and 170°. The results show unambiguously the shortcomings of calculations employing only two-body forces and the necessity of the inclusion of 3NFs. They also show the limitations of the results of the present day models for few-nucleon systems at backward angles, especially at higher beam energies. New calculations based on chiral perturbation theory are also presented and compared with the data at the lowest energy
Viability analysis and apoptosis induction of breast cancer cells in a microfluidic device: effect of cytostatic drugs
Breast cancer is the leading cause of cancer deaths among non-smoking women worldwide. At the moment the treatment regime is such that patients receive different chemotherapeutic and/or hormonal treatments dependent on the hormone receptor status, the menopausal status and age. However, in vitro sensitivity testing of tumor biopsies could rationalize and improve the choice of chemo- and hormone therapy. Lab-on-a-Chip devices, using microfluidic techniques, make detailed cellular analysis possible using fewer cells, enabling working with a patients’ own cells and performing chemo- and hormone sensitivity testing in an ex vivo setting. This article describes the development of two microfluidic devices made in poly(dimethylsiloxane) (PDMS) to validate the cell culture properties and analyze the chemosensitivity of MCF-7 cells (estrogen receptor positive human breast cancer cells) in response to the drug staurosporine (SSP). In both cases, cell viability was assessed using the life-stain Calcein-AM (CAAM) and the death dye propidium iodide (PI). MCF-7 cells could be statically cultured for up to 7 days in the microfluidic chip. A 30 min flow with SSP and a subsequent 24 h static incubation in the incubator induced apoptosis in MCF-7 cells, as shown by a disappearance of the aggregate-like morphology, a decrease in CAAM staining and an increase in PI staining. This work provides valuable leads to develop a microfluidic chip to test the chemosensitivity of tumor cells in response to therapeutics and in this way improve cancer treatment towards personalized medicine
Atmospheric effects on extensive air showers observed with the Surface Detector of the Pierre Auger Observatory
Atmospheric parameters, such as pressure (P), temperature (T) and density,
affect the development of extensive air showers initiated by energetic cosmic
rays. We have studied the impact of atmospheric variations on extensive air
showers by means of the surface detector of the Pierre Auger Observatory. The
rate of events shows a ~10% seasonal modulation and ~2% diurnal one. We find
that the observed behaviour is explained by a model including the effects
associated with the variations of pressure and density. The former affects the
longitudinal development of air showers while the latter influences the Moliere
radius and hence the lateral distribution of the shower particles. The model is
validated with full simulations of extensive air showers using atmospheric
profiles measured at the site of the Pierre Auger Observatory.Comment: 24 pages, 9 figures, accepted for publication in Astroparticle
Physic
The exposure of the hybrid detector of the Pierre Auger Observatory
The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays.
It consists of a surface array to measure secondary particles at ground level
and a fluorescence detector to measure the development of air showers in the
atmosphere above the array. The "hybrid" detection mode combines the
information from the two subsystems. We describe the determination of the
hybrid exposure for events observed by the fluorescence telescopes in
coincidence with at least one water-Cherenkov detector of the surface array. A
detailed knowledge of the time dependence of the detection operations is
crucial for an accurate evaluation of the exposure. We discuss the relevance of
monitoring data collected during operations, such as the status of the
fluorescence detector, background light and atmospheric conditions, that are
used in both simulation and reconstruction.Comment: Paper accepted by Astroparticle Physic
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