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New technique of diffuse reflectance spectroscopic analysis of milk fat and total protein content in the visible (Vis) and adjacent near infrared (NIR) region (400-995nm) has been developed and tested. Sample analysis was performed through a probe having eight 200-µm fiber channels forming a linear array. One of the end fibers was used for the illumination and other seven - for the spectroscopic detection of diffusely reflected light. One of the detection channels was used as a reference to normalize the spectra and to convert them into absorbance-equivalent units. The method has been tested experimentally using a designed sample set prepared from industrial raw milk standards with widely varying fat and protein content. To increase the modelling robustness all milk samples were measured in three different homogenization degrees. Comprehensive data analysis has shown the advantage of combining both spectral and spatial resolution in the same measurement and revealed the most relevant channels and wavelength regions. The modelling accuracy was further improved using joint variable selection and preprocessing optimization method based on the genetic algorithm. The root mean-square errors of different validation methods were below 0.10% for fat and below 0.08% for total protein content. Based on the present experimental data, it was computationally shown that the full-spectrum analysis in this method can be replaced by a sensor measurement at several specific wavelengths, for instance, using light-emitting diodes (LEDs) for illumination. Two optimal sensor configurations have been suggested: with nine LEDs for the analysis of fat and seven - for protein content. Both simulated sensors exhibit nearly the same component determination accuracy as corresponding full-spectrum analysis.

The German Federal Cartel Office and the Austrian Federal Competition Authority have recently published a draft "Guidance on Transaction Value Thresholds for Mandatory Pre-merger Notification (Section 35(1a) GWB and Section 9(4) KartG)" for public consultation. Prof. Dr. Christian Kersting, Prof. Dr. Hans Jurgen Meyer-Lindemann and Prof. Dr. Rupprecht Podszun of the Dusseldorf Institute for Competition Law evaluate the draft guidance. The draft of the guidance is available on the homepage of the Federal Cartel Office.

Three prototypes of mid-infrared (MIR) spectrometric sensor systems for simultaneous monitoring of ethanol and carbohydrates (in the present case glucose and fructose) in the course of biotechnological processes have been constructed based on recent developments in pyroelectric detection and fiber photonics. The sensors utilized were a grating spectrometer or a Fabry-Perot interferometer adjusted for the detection of analytes’ characteristic absorbance bands in the spectral region of “fingerprints” between 1050 and 950 cm −1 . The measurements were performed with an attenuated total reflection (ATR) probe connected to the spectrometer by a polycrystalline infrared fiber (PIR). Two probes with different ATR elements were tested: with a diamond crystal (for both spectrometers) and with a detachable PIR loop head (for grating spectrometer). The sensor performances were assessed and compared using partial least-squares (PLS) regression modeling and prediction statistics for two designed sample sets of binary ethanol–glucose and glucose–fructose aqueous solutions. The models based on the FT-IR spectroscopic analysis of the same designed samples using a diamond ATR probe (a “gold standard” method) were used as a benchmark. The system based on a grating spectrometer connected to an ATR probe with a PIR loop head was additionally tested under the process conditions of Saccharomyces cerevisiae fermentation. The resulting root mean-square errors of prediction were 4.74 and 13.33 g/L, for ethanol and glucose models, respectively. Simultaneously, NIR spectroscopy in the range 1100–2100 nm was used both for the analysis of designed samples and for the fermentation process monitoring. In the latter case a biomass content prediction model has been built along with those for ethanol and glucose. All tested full-spectroscopic and sensor-based methods of analysis have been compared and their practical applications discussed.

From 1986 to 1997, 41 newborn infants and 19 children (1–6 years) with pulmonary atresia and ventricular septal defect were treated at the Heart Center North Rhine-Westphalia. The infants' birth weights ranged from 1140 g to 4100 g (mean 2990 g). Eighteen of these 60 patients had significant additional cardiovascular malformations and they were excluded from this study. The results of surgical treatment in the remaining 42 patients are presented and discussed here. Twenty patients had a main pulmonary arterial trunk with confluent branch pulmonary arteries and nine had an atretic trunk with confluent pulmonary arteries. In nine patients without confluence, one branch pulmonary artery originated normally from the main pulmonary trunk and the other originated abnormally. In four patients the intrapericardial vessels were completely missing. The Nakata index measured by cineangiography ranged from 50 to 240 mm 2 /m 2 (mean 150 mm 2 /m 2 ). All newborns with a patent ductus arteriosus received prostaglandin intravenously. In eight of them oral prostaglandin was used to provide long-term stability before surgery. A total of 65 surgical aortopulmonary anastomoses were created, primary repair was carried out in six patients, and secondary corrective surgery was performed in 21 patients. After the first anastomosis, oxygen saturations increased by 5–15% (mean 8%), depending on the pulmonary vascular pathology. When a second shunt was created in the same patient, the increase in oxygen saturations ranged from none to 7%. After a mean interval of four years following the last operation, inspiratory vital capacity and intrathoracic gas volume were measured in 22 patients. Values of both studies decreased progressively as more thoracotomies were performed. All 42 patients were treated surgically and 13 died (31%). A primary or secondary repair was performed in 27 with 23 survivors (85%), and 15 had palliative procedures with six survivors (40%). Twenty of the 29 survivors (69%) are in a good clinical condition.