Phytochemistry,Medicinal Properties,Bioactive Compounds,and Therapeutic Potential of the Genus Eremophila (Scrophulariaceae)

The genus Eremophila (family Scrophulariaceae) consists of approximately 200 species that are widely distributed in the semi-arid and arid regions of Australia. Multiple Eremophila spp. are used as traditional medicines by the First Australians in the areas in which they grow. They are used for their antibacterial, antifungal, antiviral, antioxidant, anti-diabetic, anti-inflammatory, and cardiac properties. Many species of this genus are beneficial against several diseases and ailments. The antibacterial properties of the genus have been relatively well studied, with several important compounds identified and their mechanisms studied. In particular, Eremophila spp. are rich in terpenoids, and the antimicrobial bioactivities of many of these compounds have already been confirmed. The therapeutic properties of Eremophila spp. preparations and purified compounds have received substantially less attention, and much study is required to validate the traditional uses and to highlight species that warrant further investigation as drug leads. The aim of this study is to review and summarise the research into the medicinal properties, therapeutic mechanisms, and phytochemistry of Eremophila spp., with the aim of focussing future studies into the therapeutic potential of this important genus.     

Proficiency test exercise on the determination of natural levels of radionuclides in mushroom reference material

The results from a proficiency test exercise for the determination of natural levels of radionuclides in mushroom reference material carried out by laboratories in six different countries are discussed. These laboratories submitted data on seven radionuclides, namely ¹³⁴Cs, ¹³⁷Cs, ⁴⁰K, ⁹⁰Sr, ²⁴¹Am, ²²⁶Ra, and ²¹⁰Po. However, only the data received for three of these radionuclides could be statistically evaluated to obtain consensus mean values and confidence intervals (at a significance level of 0.05). The contents of ¹³⁴Cs, ¹³⁷Cs and ⁴⁰K were quantified as 4.4, 2,899 and 1,136 Bq/kg, respectively.     

Estimation of measurement uncertainty for the determination of aflatoxin M1 in milk using immunoaffinity clean-up procedures

A measurement uncertainty estimated for aflatoxin M₁ determination in milk sample has been calculated using data generated from analytical method validation studies. The protocol adopted is described in detail in document LGC/VAM/1998/088. The uncertainty budget was based on precision, trueness and ruggedness data. The individual contributions are described in detail. The expanded uncertainty for aflatoxin M ₁ at a concentration of 20 ng L⁻¹ was estimated as 2.81 ng L⁻¹. This was calculated using a coverage factor of two which gives a level of confidence of approximately 95%. Presented at AOAC Europe / Eurachem Symposium March 2005, Brussels, Belgium     

The influence of evaporative dynamics on precision in split capillary GC

The kinetics of sample evaporation was studied for four common injection liners at various temperatures. The rates of solvent and sample evaporation were measured. The sample distribution at the split point was probed by inserting two capillary columns in one injector. Greater homogeneity at the split point corresponded to higher precision (better correlation between the sample and internal standard peak areas). Evidence of aerosol formation using inverted cup inlet liners was seen. Packed column precision was better than capillary precision in each case, i.e., using straight split liners, inverted cup liners, and cold on-column injection. Capillary precision is best when the sample and internal standard elute close together, and may be improved by using solvents that vaporize slowly.     

An error model for evaluation and interpretation of proficiency testing

Data from proficiency testing can be used to increase our knowledge of the performance of populations of laboratories, individual laboratories and different measurement methods. To support the evaluation and interpretation of results from proficiency testing an error model containing different random and systematic components is presented. From a single round of a proficiency testing scheme the total variation in a population of laboratories can be estimated. With results from several rounds the random variation can be separated into a laboratory and time component and for individual laboratories it is then also possible to evaluate stability and bias in relation to the population mean. By comparing results from laboratories using different methods systematic differences between methods may be indicated. By using results from several rounds a systematic difference can be partitioned into two components: a common systematic difference, possibly depending on the level, and a sample-specific component. It is essential to distinguish between these two components as the former may be eliminated by a correction while the latter must be treated as a random component in the evaluation of uncertainty. Received: 20 November 2000 Accepted: 3 January 2001     

Tests of fundamental symmetries and interactions – using nuclei and lasers

State of the art laser technology and modern spectroscopic methods allow to address issues of fundamental symmetries and fundamental interactions in atoms with high precision experiments. In particular the discrete symmetries Parity (P), Charge Conjugation (C), Time Reversal (T) as well as their combinations CP and CPT are in the center of interest at present. Actual projects are concerned with Parity Violation in atoms, Time Reversal Violation in β-decays and searches for permanent Electric Dipole Moments (EDMs), and tests of CPT conservation in particle-antiparticle properties, in particular antiprotonic atoms. This work is supported in part by the Dutch Stichting voor Fundamenteel Onderzoek der Materie (FOM) under programme number 48 (TRIμP).     

Monitoring of technical oils in supercritical CO(2) under continuous flow conditions by NIR spectroscopy and multivariate calibration

Metal parts and residues from machining processes are usually polluted with cutting or grinding oil and have to be cleaned before further use. Supercritical carbon dioxide can be used for extraction processes and precision cleaning of metal parts, as developed at Forschungszentrum Karlsruhe. For optimizing and efficiently conducting the extraction process, in-line analysis of oil concentration is desirable. Therefore, a monitoring method using fiber-optic NIR spectroscopy in combination with PLS calibration has been developed. In an earlier paper we have described the instrumental set-up and a calibration model using the model compound squalane in the spectral range of the CH combination bands from 4900 to 4200 cm⁻¹. With this model only poor prediction results were obtained if applied to technical oil samples in supercritical CO₂. In this paper we describe a new calibration model, which was set up for the squalane/carbon dioxide system covering the 323–353 K temperature and the 16–35.6 MPa pressure range. Here, calibration data in the spectral range from 6100 to 5030 cm⁻¹ have been used. This range includes the 5100 cm⁻¹ CO₂ band of the Fermi triad as well as the hydrocarbon 1st overtone CH stretching bands, where spectral features of oil compounds and squalane are more similar to each other.

The root mean-squared error of prediction obtained with this model is 4 mg cm⁻³ for carbon dioxide and 0.4 mg cm⁻³ for squalane, respectively. The utilizability of the newly developed PLS calibration model for predicting the oil concentration and CO₂ density of solutions of technical oils in supercritical carbon dioxide has been tested. Three types of “real world” cutting and grinding oil formulations were used in these experiments. The calibration proved to be suitable for determining the technical oil concentration with an error of 1.1 mg cm⁻³ and the CO₂ density with an error of 6 mg cm⁻³. Therefore, it seems possible to apply this in-line analytical approach on the basis of a cost-effective and time-saving model compound calibration for the surveillance of real world de-oiling and other extraction process based on supercritical carbon dioxide, and furthermore to establish an automated process termination criterion based on this technique.     

Traceability system for elemental analysis

A complete metrological traceability system for measurement results of chemical analysis was set up. Core components are pure substances (national standards) characterised at the highest metrological level, primary solutions prepared from these pure substances and secondary solutions deduced from the primary solutions and intended for sale. The relative uncertainty of the element mass fraction of the primary substances and solutions is < 0.01 and < 0.05%, respectively. For the certification of transfer solutions and for stability testing, a precision measurement method for element contents has been developed by means of optical emission spectrometry (ICP OES) by which uncertainties between 0.1 and 0.05% can be achieved. The dissemination to field laboratories is effected with the aid of a calibration laboratory of the German Calibration Service (DKD) which certifies the element content of the secondary solutions with an uncertainty ≤ 0.3%. Calibration with these solutions enables the user to establish traceability of his measurement results to the International System of Units (SI). Currently, the system comprises Cu, Fe, Bi, Ga, Si, Na, K, Sn, W, and Pb.     

靶丸表面轮廓形貌AFM精密测量及特性评价

 建立了由改造的原子力显微镜(AFM)、精密回转气浮轴系、辅助转位轴系等组成的靶丸表面形貌精密测量系统,气浮轴系的回转精度达0.049 μm,实现了对激光核聚变靶丸3个正交方向上完整圆周迹线的测量。对选定靶丸的测量数据进行了球度、表面粗糙度及功率谱分析。结果表明：其球度值为0.42 μm;模数范围为2~10,11~50,51~100及101~1 000对应的表面粗糙度值平均为105.7, 12.2, 6.2, 18.25 nm;并得出了平均1维功率谱-模数关系曲线。     

C^1保单调有理二次插值

本文提供一类保单调分段有理二次插值方法。插值公式具有两个可调的形状参数。逼近精度为Ｏ（ｈ＾２）。