Das Kind in Pietismus und Aufklärung

Ohne Zusammenfassung     

Erfahrungen mit Mehrproduktanlagen

Experience Gained with Multipurpose Plants. Multipurpose plants are used in many fields of production. Some products often have a short life cycle or are not in continuous demand; hence these plants undergo constant changes. In order to control these changes from an economical point of view, certain boundary conditions must be met. The following article describes which questions have to be asked and answered and which structures prove to be advantageous for such plants.     

Liquid nitrogen energy storage unit

An energy storage unit is a device able to store thermal energy with a limited temperature drift. After precooling such unit with a cryocooler it can be used as a temporary cold source if the cryocooler is stopped or as a thermal buffer to attenuate temperature fluctuations due to heat bursts. In this article, after a brief study of the possible solutions for such devices, we show that a low temperature cell filled with liquid nitrogen and coupled to a room temperature expansion volume offers the most compact and light solution in the temperature range 60–80 K. For instance, a low temperature cell as small as 23 cm³ allows the storage of 3.7 kJ between 76 K and 81 K. Experimental results were obtained varying the expansion volume size, the filling pressure and the temperature range. These results agree with our simple model based on thermodynamical properties of nitrogen. A cell filled with porous material was tested to confine the liquid in the cell independently of the gravity. This material enhances the thermal exchange for high liquid filling ratio whereas below ≈16% a solution must be found to improve the heat exchange coefficient between the fluid and the cell walls. Our calculations are extended to the 80–120 K temperature range for nitrogen and argon in order to clarify the various parameters to take into account for an energy storage unit dimensioning.     

Czech primary radon measurement equipment

The Authorized Metrological Centre (AMS) working by SUJCHBO (National Institute for Nuclear, Chemical and Biological Protection) ensures for the Czech Republic the metrological traceability for devices that measure the radon concentration and the energy equivalent radon concentration connected with the radon decay products (RnDP). The evaluation and the calibration of measuring devices for radon and RnDP require the stable conditions (first of all radon and the RnDP concentrations). The new AMS radon-aerosol chamber in Kamenná consists of the walk-in testing chamber with a volume of 10 m(3) and of the handling box with a volume of 0.3 m(3). The design of the chamber allows measurement and a control of environmental parameters such as the temperature, the pressure of air inside and outside of the chamber, the relative humidity of air, the concentration and the size distribution of aerosol particles and the air velocity.     

Model-independent tests of cosmic gravity

Gravitation governs the expansion and fate of the universe, and the growth of large-scale structure within it, but has not been tested in detail on these cosmic scales. The observed acceleration of the expansion may provide signs of gravitational laws beyond general relativity (GR). Since the form of any such extension is not clear, from either theory or data, we adopt a model-independent approach to parametrizing deviations to the Einstein framework. We explore the phase space dynamics of two key post-GR functions and derive a classification scheme, and an absolute criterion on accuracy necessary for distinguishing classes of gravity models. Future surveys will be able to constrain the post-GR functions' amplitudes and forms to the required precision, and hence reveal new aspects of gravitation.     

The comparative effectiveness of cognitive processing therapy for male veterans treated in a VHA posttraumatic stress disorder residential rehabilitation program.

Objective: To examine the effectiveness of group cognitive processing therapy (CPT) relative to trauma-focused group treatment as usual (TAU) in the context of a Veterans Health Administration (VHA) posttraumatic stress disorder (PTSD) residential rehabilitation program. Method: Participants were 2 cohorts of male patients in the same program treated with either CPT (n = 104) or TAU (n = 93; prior to the implementation of CPT). Cohorts were compared on changes from pre- to posttreatment using the PTSD Checklist (PCL; Weathers, Litz, Herman, Huska, & Keane, 1993) and other measures of symptoms and functioning. Minorities represented 41% of the sample, and the mean age was 52 years (SD = 9.22). The CPT group was significantly younger and less likely to receive disability benefits for PTSD; however, these variables were not related to outcome. Results: Analyses of covariance controlling for intake symptom levels and cohort differences revealed that CPT participants evidenced more symptom improvement at discharge than TAU participants on the PCL, F(3, 193) = 15.32, p     

Genome of non-living cells: trash or recycle?

Reproductive technologies have been often used as a tool in research not strictly connected with developmental biology. In this study, we retrace the experimental routes that have led to the adoption of two reproductive technologies, ICSI and somatic cell nuclear transfer (SCNT), as biological assays to probe the 'functionality' of the genome from dead cells. The structural peculiarities of the spermatozoa nucleus, namely its lower water content and its compact chromatin structure, have made it the preferred cell for these experiments. The studies, primarily focused on mice, have demonstrated an unexpected stability of the spermatozoa nuclei, which retained the capacity to form pronuclei once injected into the oocytes even after severe denaturing agents like acid treatment and high-temperature exposure. These findings inspired further research culminating in the production of mice after ICSI of lyophilized spermatozoa. The demonstrated non-equivalence between cell vitality and nuclear vitality in spermatozoa prompted analogous studies on somatic cells. Somatic cells were treated with the same physical stress applied to spermatozoa and were injected into enucleated sheep oocytes. Despite the presumptive fragile nuclear structure, nuclei from non-viable cells (heat treated) directed early and post-implantation embryonic development on nuclear transfer, resulting in normal offspring. Recently, lyophilized somatic cells used for nuclear transfer have developed into normal embryos. In summary, ICSI and SCNT have been useful tools to prove that alternative strategies for storing banks of non-viable cells are realistic. Finally, the potential application of freeze-dried spermatozoa and cells is also discussed.