Multiplex real-time PCR for the detection and quantification of DNA from beef,pork, horse and sheep

Meat products are often composed of more than one meat species. A quantitative multiplex PCR was developed to determine the proportion of meat fractions of beef, pork, horse and sheep. The precision and accuracy were investigated by dilutions of DNA from all four species and examining different meat products from the market. Application of this tetraplex quantitative real-time PCR system will enable official food control and production control laboratories to efficiently investigate the composition of meat products.     

Discovery and structural elucidation of the illegal azo dye Basic Red 46 in sumac spice

An unknown red dye was discovered in a sumac spice sample during routine analysis for Sudan dyes. LC-DAD and LC-MS/MS did not reveal the identity of the red substance. Nevertheless, using LC-high-resolution MS and isotope ratio comparisons the structure was identified as Basic Red 46. The identity of the dye was further confirmed by comparison with a commercial hair-staining product and two textile dye formulations containing Basic Red 46. Analogous to the Sudan dyes, Basic Red 46 is an azo dye. However, some of the sample clean-up methodology utilised for the analysis of Sudan dyes in food prevents its successful detection. In contrast to the Sudan dyes, Basic Red 46 is a cation. Its cationic properties make it bind strongly to gel permeation columns and silica solid-phase extraction cartridges and prevent elution with standard eluents. This is the first report of Basic Red 46 in food. The structure elucidation of this compound as well as the disadvantages of analytical methods focusing on a narrow group of targeted analytes are discussed.     

Improvements and complications involved with adding an 85-GHzchannel to cloud liquid water radiometers

The improvement in cloud-liquid estimates by a microwave radiometer with the addition of measurements at 85 GHz is quantified. Atmospheric emission is simulated from radiosonde data at frequencies commonly used by ground-based water-vapor radiometers (22.235 and 31.65 GHz) and also at 85.5 GHz. Retrieval algorithms are developed from opacities based on full Mie extinction by cloud droplets and under an assumption that ice effects are not significant for downwelling emission. The algorithms use either three frequencies or only the lower two. The inclusion of 85-GHz information significantly improves liquid-water path estimates at all levels of integrated liquid water. The Rayleigh approximation is shown to be valid for most cloudy conditions. Uncertainty in the calculated opacities due to varying cloud droplet-size distributions and liquid-water content profiles is quantified. The accuracy of a retrieval algorithm trained by Rayleigh approximation opacities and including the additional uncertainty is shown to provide estimates with error levels similar to those from the algorithm trained with full Mie opacities     

TOPEX/Poseidon microwave radiometer (TMR). III. Wet troposphererange correction algorithm and pre-launch error budget

For pt.II see ibid., vol.33, no.1, p.138-46 (1995). The sole mission function of the TOPEX/Poseidon microwave radiometer (TMR) is to provide corrections for the altimeter range errors induced by the highly variable atmospheric water vapor content. The three TMR frequencies are shown to be near-optimum for measuring the vapor-induced path delay within an environment of variable cloud cover and variable sea surface flux background. After a review of the underlying physics relevant to the prediction of 5-40 GHz nadir-viewing microwave brightness temperatures, the authors describe the development of the statistical, two-step algorithm used for the TMR retrieval of path delay. Test simulations are presented which demonstrate the uniformity of algorithm performance over a range of cloud liquid and sea surface wind speed conditions. The results indicate that the inherent algorithm error (assuming noise free measurements and an exact physical model) is less than 0.4 cm of retrieved path delay for a global representation of atmospheric conditions. An algorithm error budget is developed which predicts an overall algorithm accuracy of 0.9 cm when modeling uncertainties are included. When combined with expected TMR antenna and brightness temperature accuracies, an overall measurement accuracy of 1.2 cm for the wet troposphere range correction is predicted     

LogScheme: Integrating logic programming into Scheme

This research aims to fully integrate logic programming into the programming language Scheme. We use a minimalist approach, based on the observation that the fundamental aspects of logic programming, nondeterminism and unification, are separable both in concept and in implementation. We have found that only two new primitive functions and one new special form need to be added to Scheme to achieve this integration. Using these primitives, we can write programs in the style of Scheme, Icon, Prolog, or any mixture thereof. We have found that a style of programming that uses both logical and functional techniques can be more powerful than the use of either technique alone. Because Scheme has side effects and continuations, this research addresses different problems and choices than previous research [2, 16, 19] on merging functional and logical languages.An earlier version of this paper was published in theProceedings of the 4th ACM Conference on Functional Programming Languages and Computer Architecture, as Non-determinism and Unification in LogScheme, pp. 327–339.Supported in part by an AT&T Bell Laboratories Ph.D. Scholarship.Supported by Defense Advanced Research Projects Agency contract # N00014-87-K-0828.     

Infrastructure Challenges Caused by Industrial Transformation to Achieve Greenhouse Gas Neutrality. Ammonia Production in the Antwerp-Rotterdam-Rhine-Ruhr Area

Several pathways for potentially greenhouse gas neutral production of ammonia have been investigated compared to today's conventional ammonia production at chemical sites in Antwerp, Dormagen, and Geleen. These pathways include on-site water electrolysis using grid electricity, off-site production via water electrolysis using renewable electricity and supply of green hydrogen to the site, pyrolysis of natural gas and conventional ammonia production coupled with CO₂-capture on-site and transport to a storage site. All pathways effectively eliminate scope 1 emissions present in conventional production but continue to emit scope 2 emissions from grid electricity consumption. Eventually, a coordinated industry-wide and cross-industry effort is needed to address the transformational changes and develop the common cross-border infrastructures.     

Retention properties of efficient adsorbent to silver(I)

The binding capability of crosslinked poly(acrylic acid‐co‐2‐acrylamide‐2‐methyl‐1‐propane sulfonic acid) for silver(I) ions by the batch equilibrium method is investigated. The effects of the pH, temperature, time of contact, and resin–metal ion molar ratio on the retention ability are studied. The retention for silver(I) increases from 21.7% at pH 1 to 94.6% at pH 5. The adsorption capacity at pH 5 is 1.18 meq/g dry resin. The maximum load capacity at the optimum pH is determined. In order to recover the resin, elution runs in acid and basic media are carried out. The best eluent is 4M HNO₃ (84.9%). Moreover, retention–elution cycles are performed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1501–1506, 2002     

Microwave Radiometer Radio-Frequency Interference Detection Algorithms: A Comparative Study

Two algorithms used in microwave radiometry for radio-frequency interference (RFI) detection and mitigation are the pulse detection algorithm and the kurtosis detection algorithm. The relative performance of the algorithms is compared both analytically and empirically. Their probabilities of false alarm under RFI-free conditions and of detection when RFI is present are examined. The downlink data rate required to implement each algorithm in a spaceborne application is also considered. The kurtosis algorithm is compared to a pulse detection algorithm operating under optimal RFI detection conditions. The performance of both algorithms is also analyzed as a function of varying characteristics of the RFI. The RFI detection probabilities of both algorithms under varying subsampling conditions are compared and validated using data obtained from a field campaign. Implementation details, resource usage, and postprocessing requirements are also addressed for both algorithms.