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A novel apparatus in which fluids may be injected and sampled at high pressure is described. Bioseparation applications of the apparatus were demonstrated in three model systems: (1) λDNA was eluted under pressure from an anion exchange column into a low-salt (0.25 M) buffer, thereby eliminating conventional time-consuming desalting procedures required for downstream analysis of the DNA; (2) RNA was separated under pressure from a RNA/DNA mixture, thereby enabling rapid differential preparation of nucleic acids; and (3) an antibody was purified from a protein mixture by affinity capture at one pressure and dissociation from the antigen binding partner at a second pressure, thereby enabling the immunoreactivities of both antibody and antigen to be preserved during the separation process.

The gain in experience with long-pulse operation under fusion relevant plasma conditions is an important step towards successful sustainment of future steady state reactor plasmas. The stellarator Wendelstein 7-X (W7-X) [1], presently being under construction, is already equipped with a superconducting coil system and principally capable of quasi-continuous operation. Like other long pulse devices, W7-X is faced with new enhanced technical requirements which have to be met by plasma facing components as well as the diagnostic systems in general. Water-cooled windows were qualified up to 60 kW/m2 thermal load, and shutters against evaporation of sensitive elements outside the attended time of the diagnostic as well as for baseline control had been developed. Shielding of in-vessel components against damage by absorption of microwave stray radiation originating from the heating systems appears to be one of the most challenging tasks. Experiments using a microwave test chamber identify critical materials and approved the necessity for careful shielding of both, sensitive diagnostics and cables. Spectroscopic systems for monitoring the impurity content and divertor load as well as for robust density measurement are presented (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

At the TEXTOR tokamak in Jülich, Germany, a modular dispersion interferometer was installed and operated for the first time. Equipped with four lines of sight, the line-integrated density could be measured in parallel at different major radii with a resolution of better than 3 × 10(17) m(-2). This paper will describe the setup and show the first measurement results. Among others, it was possible to detect the evolution of a disruption with a time resolution of 4 μs. The movement of the runaway beam following the disruption could be resolved spatially and temporarily.

The status of the diagnostic developments for the quasistationary operable stellarator Wendelstein 7-X (maximum pulse length of 30 min at 10 MW ECRH heating at 140 GHz) will be reported on. Significant emphasis is being given to the issue of ECRH stray radiation shielding of in-vessel diagnostic components, which will be critical at high density operation requiring O2 and OXB heating. © 2010 American Institute of Physics

A second harmonics or dispersion interferometer (DI) is a promising approach for the measurement of line-integrated densities on fusion devices. In contrast to a conventional twocolor interferometer, the second harmonics (SH) of an interferometer beam, generated by a non-linear optical crystal, is used as the second probing beam. Since a few years, non-linear crystals with a sufficient conversion rate are available for the infrared (IR) spectrum around 10 %m. Several types of these IR non-linear crystals have the phase-matching angle range as big as ≈1°, which is a great advantage for SH generation applications. Among other advantages, dispersion interferometers offer the possibility of a highly compact frameless design, which makes a modular approach possible for multi-channel diagnostics. Another unique feature is that vibrations are compensated intrinsically. This work will analyze the performance of a 10.6 %m DI currently under construction at the TEXTOR tokamak.

The stellarator Wendelstein 7-X will allow for quasicontinuous operation with the duration only being limited to two 30 min discharges per day, at a continuous heating power of 10 MW electron cyclotron resonance heating (ECRH) at 140 GHz, by the capacity of the cooling water reservoir. This will result in high thermal loads on all plasma facing components of 50-100 kW/m(2) from radiation alone and of up to about 500 kW/m(2) on components additionally exposed to convective loads. In high density scenarios toroidally varying ECRH stray radiation levels of 50-200 kW/m(2) need to be coped with, requiring careful material selection and different shielding and hardening techniques. Furthermore, a gradual buildup of coatings on plasma facing optical components, which without any measures being taken, would lead to high transmission losses already within a few days of long pulse operation (equivalent to about 1 year of operation in pulsed devices like JET or ASDEX-upgrade) and therefore needs to be prevented as much as possible. In addition in situ cleaning as well as absolute calibration techniques need to be developed for all plasma facing optical systems. Here we report about some of our efforts to find, for various types of diagnostics, ways to cope with these adverse effects. Moreover, we give a few examples for individual diagnostic specific issues with respect to quasicontinuous operation, such as the development of a special integrator for the magnetic diagnostics as well as special interferometer types which can cope with unavoidable vibrations and slow path length changes due to, e.g., thermal expansion of the plasma vessel.

Data Adaptive Planning determines the expected utility of a single new measurement using existing data and a data descriptive model. The method can be used for experimental planning. It is applied to scaling laws for magnetic fusion devices. Explicitly, the scaling of the stellarator W7-AS is examined for a subset of ι= 1/3 data. In control parameter space regions of high utility are identified and serve for fixing discharge and machine parameters for upcoming discharges. It will be shown that a skillful analysis of experimental uncertainties is of utmost importance for significant results.

For the optimisation of the beam line configuration of the multi-channel interferometer at the Wendelstein 7-X stellarator the probabilistic approach of Bayesian experimental design (BED) is applied. Parameters of physical interest are directly implemented as design criteria. The quality of the design is analysed according to its expected information gain (expected utility) about the parameters of interest, which enables one to compare different diagnostic configurations quantitatively. The focus of this work lies on the comparison of different technical approaches for the interferometer diagnostic. Different physical problems (high confinement regimes, neoclassical predictions) and their effect on the density distribution are applied as optimisation goals. The influence of the port system and the in-vessel components (retro-reflectors) is discussed. For this, the design was done with and without technical restrictions, the resulting expected utilities are compared and analysed. Furthermore, the impact of an additional beamline at a different toroidal position (congruent to the Thomson scattering diagnostic) is examined.

Bayesian experimental design (BED) is a framework for the optimization of diagnostics basing on probability theory. In this work it is applied to the design of a multichannel interferometer at the Wendelstein 7-X stellarator experiment. BED offers the possibility to compare diverse designs quantitatively, which will be shown for beam-line designs resulting from different plasma configurations. The applicability of this method is discussed with respect to its computational effort.

The diagnostic set‐up for Wendelstein 7‐X, a magnetic fusion device presently under construction, is currently in the design process to optimize the outcome under given technical constraints. Compared to traditional design approaches, Bayesian Experimental Design (BED) allows to optimize with respect to physical motivated design criterions. It aims to find the optimal design by maximizing an expected utility function that quantifies the goals of the experiment. The expectation marginalizes over the uncertain physical parameters and the possible values of future data. The approach presented here bases on maximization of an information measure (Kullback‐Leibler entropy). As an example, the optimization of an infrared multichannel interferometer is shown in detail. Design aspects like the impact of technical restrictions are discussed.

Any scientist planning experiments wants to optimize the design of a future experiment with respect to best performance within the scheduled experimental scenarios. Bayesian Experimental Design (BED) aims in finding optimal experimental settings based on an information theoretic utility function. Optimal design parameters are found by maximizing an expected utility function where the future data and the parameters of physical scenarios of interest are marginalized. The goal of the Integrated Bayesian Experimental Design (IBED) concept is to combine experiments as early as on the design phase to mutually exploit the benefits of the other experiments. The Bayesian Integrated Data Analysis (IDA) concept of linking interdependent measurements to provide a validated data base and to exploit synergetic effects will be used to design meta‐diagnostics. An example is given by the Thomson scattering (TS) and the interferometry (IF) diagnostics individually, and a set of both. In finding the optimal experimental des...

The concept of integrated data analysis in nuclear fusion requires the linkage of data and physical information. Summarizing the key steps for the analysis of transport in the core plasma, benefits of probabilistic modelling of single diagnostics are discussed. Concepts for full diagnostics models consisting of several diagnostics modules and linkage through mapping procedures are given in figures of Bayesian graphical models. Coupling to theory codes is demonstrated by the error estimation of neoclassical error analysis allowing a quantitative physical model validation. As an inverted use of the integrated data analysis approach, goals for the design of diagnostics and sets of diagnostics (meta‐diagnostics) are outlined.

The design and main characteristics of 14-channel dispersion interferometer for plasma profile measurement and control in TEXTOR tokamak are presented. The diagnostic is engineered on the basis of modular concept, the 10.6 microm CO(2) laser source and all optical and mechanical elements of each module are arranged in a compact housing. A set of mirrors and retroreflectors inside the TEXTOR vacuum vessel provides full coverage of the torus cross section with 12 vertical and two diagonal lines of sight, no rigid frame for vibration isolation is required. Results of testing of the single-channel prototype diagnostic and the pilot module of the multichannel dispersion interferometer are presented.

An eight channel interferometer is developed for density feedback control and the continuous measurement of electron density profiles in the stellarator W7-X. An additional sightline is launched in the geometry of the Thomson scattering for cross calibration. Due to the W7-X coil geometry access is strongly restricted. This motivates the optimization of the sightline geometry and design studies for supplementary chords. In-vessel retroreflectors will be used and inserted in the first wall elements. To cope with associated mechanical vibrations and thermal drifts during the discharges with envisaged duration of 30min either two-color or second harmonic interferometry techniques must be applied. Optimum wavelengths are found to be about 10 and 5μm. A CO2∕CO interferometer (10μm∕5μm) will be tested and compared with an existing CO2∕HeNe test interferometer. A special difficulty of remotely operated diagnostics is the need of long transmission lines with a path length of about 60m required from the diagnostic...

Using Adler's chromostatics and the leading-logarithm, renormalization group improved Euclidean action for the gluon fields, it is shown that the colour singlet hybrid state of quark-antiquark-gluon (qg) should be as well defined as the corresponding meson (q), baryon (qqq) or glueball (gg) states. For simplicity the colour gauge group is chosen to be SU(2).

(1948). Rural Background Found in Six Third-Grade Arithmetic Texts Published between 1942 and 1946. The Journal of Educational Research: Vol. 42, No. 4, pp. 295-306.

IN A STUDY of the achievement of Minnesota youth attending 6th, 9th, and 12th grades in rural schools the author used the SeweU Socio Economic Status Scale ? short form*. The 2,731 pupils who com pleted this form in the spring of 1948 were attending one room un graded and larger graded schools located in places with 1940 popula tions of less than 2,500. The schools included in the study were lo cated in 41 different Minnesota counties. This paper will compare the socio-economic scores made by the rural students who attended the one-room ungraded schools with those who attended the larger graded schools having one or two grades per teacher. It will show the cor relation coefficients obtained between the socio-economic scale score and other measures of achievement and ability and will present norms for the SeweU Scale based on this group. The Sewell Scale was used in the study because a measure of the economic and social level of rural students' homes was needed. Sew eU's scale was devised for this purpose. 2 The short form was de vised to give essentially the same information as the longer form. ^ The scale had been satisfactorily used by Arny in Minnesota, ^ and by

'Fast track' construction and a team approach enabled a hospital and its outside experts to plan and build an ambulatory care center within 14 months and within a tight budget.

The corpus luteum periodicum (c.l.p.) of the bitch was studied using enzyme histochemistry, clinical and biochemical methods. Assessment of variations of the serum progesterone level during different stages of the ovarian cycle and the study of enzymatic activity of the luteal tissue furnished informations on vitality and biosynthetic capacity of luteinizing cells: The period of functional activity of the c.l.p. nearly ceased about day 60 of the cycle (proestrus included) in the animals examined. In the light microscope the neo-synthesis of progesterone in the c.l.-tissue can be made visible by histochemical demonstration of the activity of Delta(5)-3 beta-hydroxysteroiddehydrogenase (3 beta-HSD) only up to a progesterone level exceeding 6.7 ng/ml plasma. The data obtained contribute to our baseline knowledge of the mechanism involved in the etiology of pseudopregnancylike conditions in the bitch.

A framework for diagnostics design based on Bayesian probability theory is introduced. The design is assessed in figures of an expected utility which measures the information gain from measurements. The approach is applied on design studies for a multichord interferometer for Wendelstein 7-X.

We propose to use dispersion interferometer for measurement of plasma density and control of plasma position on present and future fusion devices. Distinguishing feature of this scheme is probing o...

A general method for the design of diagnostics by means of Bayesian probability theory is outlined. Case studies are discussed for two diagnostics planned for Wendelstein 7-X (W7-X). First, line-of-sight optimization for interferometry meeting with physical optimization targets is investigated. The filter transmission bandwidth for Thomson scattering in W7-X is discussed as a second example.

As a member of the Iowa Commission for Senior Citizens it is a real satisfaction to look over the 91-page report of the survey we had asked for—a survey of Life After 60 in Iowa . More than a thousand persons in thirteen counties were asked hundreds of questions. The objective of the survey? "To obtain up-to-date information about DIFFICULTIES faced by our older citizens in the state." It was interesting to note that in the first four pages of the survey report the words "difficulties" and "problems" were used 27 times! Life After 60 in Iowa! Were we wise in giving so much thought and time and space to "problems" and "difficulties?" Iowa has tremendous resources in its citizens past 60 years of age. There are perhaps 350,000 of them with some 5 million years of time still ahead. Should we be thinking mainly of their "problems" and "difficulties" or