Types of meningococci isolated from carriers and patients in a non-epidemic period in the netherlands

In a non-epidemic period the carrier rate of meningococci among 60 members of the laboratory staff during a long-term observation period of 1.5 years was 38%.In a children's home only a few children were carriers. The meningococci practically did not spread.In 161 recruits observed for periods of at most eight weeks the percentage of positives was 39.1 on the day of joining up and reached its maximum of 80.1 in the course of the period of observation.Among the strains isolated from patients and from carriers, type B predominated. In patients, type C was second in frequency; in carriers, type Y. Type A was found very rarely in carriers and somewhat more frequently in patients.The high carrier rate of type B in adults, together with its low aggressiveness for persons older than ten, may explain the relatively high frequency of the disease in the younger age groups.     

Genetische Untersuchungen zur Chiasmabildung und Interferenzwirkung beiDrosophila

Ohne ZusammenfassungErschienen als Dissertation der Naturwissenschaftlichen Fakultät der Martin Luther-Universität Halle-Wittenberg. D 3.Bezüglich I vgl. diese Zeitschrift, Bd. 69, 1935, S. 1–35 (Ludwig). Teil II erscheint in Kürze.Mit 14 Textfiguren und 7 Tabellen     

Die Histologische Struktur des Sprossvegetationskegels Einiger Commelinaceen unter Berücksichtigung Panaschierter Formen

Ohne ZusammenfassungMit 23 Textabbildungen.     

Correlation of <Emphasis Type="Italic">trans</Emphasis>-Lycopene Measurements by the HPLC Method with the Optothermal and Photoacoustic Signals and the Color Readings of Fresh Tomato Homogenates

The trans-lycopene content of fresh tomato homogenates was assessed by means of the laser photoacoustic spectroscopy, the laser optothermal window, micro-Raman spectroscopy, and colorimetry; none of these methods require the extraction from the product matrix prior to the analysis. The wet chemistry method (high-performance liquid chromatography) was used as the absolute quantitative method. Analytical figures of merit for all methods were compared statistically; best linear correlation was achieved for the chromaticity index a* and chroma C*.     

Sedimentation coefficients of self-associating species: I. Basic theory

Under the same solution conditions, the apparent weight average sedimentation coefficient, s_wa, and some quantities obtained from it can be combined with the equilibrium constant or constants, K_i, and the monomer concentration, c_I, obtained from sedimentation equilibrium, light scattering or osmotic pressure experiments on the same self-associating solute, so that the individual sedimentation coefficients, s_i, of the self-associating species, and also the hydrodynamic concentration dependence parameter,g or $\text{g}$, can be evaluated. Using two different models for the hydrodynamic concentration parameter, four different methods are presented for the evaluation of the s_i's. Methods for evaluating g or $\text{g}$, once the s_i's are known, are presented. A method for obtaining the number average sedimentation coefficient, s_N, and its application to self-associations is presented. Methods are shown for the evaluation of Z average properties, x_zc, as well as number average properties,x_Nc, of a self-associating solute from its weight average properties, x_wc.