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The combination of Raman and infrared spectroscopy on the one hand and wavelength selection on the other hand is used to improve the partial least-squares (PLS) prediction of seven selected yarn properties. These properties are important for on-line quality control during production. From 71 yarn samples, the Raman and infrared spectra are measured and reference methods are used to determine the selected properties. Making separate PLS models for all yarn properties using the Raman and infrared spectra, prior to wavelength selection, reveals that Raman spectroscopy outperforms infrared spectroscopy. If wavelength selection is applied, the PLS prediction error decreases and the correlation coefficient increases for all properties. However, a substantial wavelength selection effect is present for the infrared spectra compared to the Raman spectra. For the infrared spectra, wavelength selection results in PLS prediction errors comparable with the prediction performance of the Raman spectra prior to wavelength selection. Concatenating the Raman and infrared spectra does not enhance the PLS prediction performance, not even after wavelength selection. It is concluded that an infrared spectrometer, combined with a wavelength selection procedure, can be used if no (suitable) Raman instrument is available.

.Purpose:
To determine the value of electrophysiological findings in patients with temporal lobe epilepsy and to relate these findings to the amount of concentric contraction of the visual field and the use of vigabatrin.
Methods:
Electro-retinograms and electro-oculograms were done on 30 patients, operated for temporal lobe epilepsy. The patients were divided into three groups: (A) concentric contraction of the visual field associated with a history of vigabatrin medication (15 patients), (B) normal visual field with vigabatrin use (11 patients) and (C) normal visual field without vigabatrin medication (4 patients).
Results:
Electrophysiological abnormalities were found in 50% of the patients in group A. The Arden ratio of the EOG was lowered in 57%. Abnormalities in the ERG were found: b-wave implicit time photopic F was prolonged (50%), b-wave amplitudes scotopic B (53%), C (73%) and G (50%) and photopic H (50%) were diminished. The amount of visual field loss and the total dose of vigabatrin used, showed only slight correlation with the ERG and EOG. The use of vigabatrin during the ERG and EOG recording in group A, gave a higher b-wave amplitude scotopic G in 64% of cases. The a-wave implicit times scotopic G (73%) and photopic G (59%) and H (73%) were shortened in group B.
Conclusion:
EOG was abnormal in 57% in group A. ERG abnormalities could only be found in 50% of group A, mainly in the inner retina. Since also the total dose of vigabatrin and the amount of visual field loss did not really show a correlation with the electrophysiological findings and results of literature are not unanimous, electrophysiology does not appear at present to be a good method to detect patients with, or at risk of, vigabatrin associated visual field loss. Regularly performed visual field examination remains the cornerstone in screening.

The separation of demolition waste into three fractions-wood (required purity >90%), plastic (required purity >80%), and stone (no requirement)—has been investigated. The materials are measured with diffuse near-infrared reflectance spectroscopy and classified with linear discriminant analysis (LDA). To speed up the classification, simulated annealing extracts the six most discriminating wavelength regions for each preprocessing technique. For improvement in the classification results, several preprocessing techniques are investigated. Both the reflectance Rand log 10(1/R) are investigated. The influence of the so-called wavelength shift (radiation that does not pass a filter perpendicular and shifts maximally 6 nm to lower wavelength) is accounted for during wavelength selection. Preprocessing methods that remove spectral offset differences and remove differences in peak heights give the best classification improvement. Modified standard normal variate (SNV) preprocessing, applied on the reflectance R, is the best preprocessing technique. The modification is the addition of the mean spectral value after the application of standard SNV preprocessing. The mean spectral value contains some additional information that is used by the (LDA) algorithm to improve the classification performance. The influence of the so-called wavelength shift effect is minimal.

A previous study on the basis of long-range side-scan sonar data (Kenyon et al., 1995. Geometry of the younger sediment bodies of the Indus Fan. In: Pickering, K.T., Hiscott, R.N., Kenyon, N.H., Ricci Lucchi, F., Smith, R.D.A. (Eds.), Atlas of deep water environments: architectural style in turbidite systems. Chapman and Hall, London, pp. 89–93.) revealed a distributary complex of large channel–levee systems radiating from the mouth of the Indus Canyon and lower-order distributary complexes, each consisting of several smaller channel–levee systems, on the middle Indus Fan. Sediment cores from the Indus Canyon and the middle Indus Fan are analysed in this study in order to reconstruct the timing of turbidite sedimentation on the fan. Sediment cores from the middle fan show that turbidite sedimentation of the last but one switched to the last and youngest channel–levee system at the transition from oxygen-isotope stage 3 to 2 (∼24.8 14C ka BP) and ceased during the last deglaciation (∼11.5 14C ka BP). The Indus Fan is subsequently draped by a calcareous ooze of approximately Holocene age. Turbidite sedimentation continued up to (sub)recent times within the main feeder channel and Indus Canyon. The geochemical, mineralogical and grain-size analyses suggest that the sediments deposited on the middle fan during the last glacial period were mainly supplied by the Indus River (fluvial sediments) while during the Holocene they were derived predominantly from the Arabian Peninsula (eolian dust). Although major erosional and depositional cycles on the Indus Fan are strongly controlled by changes in sea level, climate-induced differences in sediment supply and autocyclic mechanisms also influenced fan sedimentation.

The input of terrigenous sediment along the tectonically active Makran continental margin off south-western Pakistan (Gulf of Oman, northern Arabian Sea) is studied on the basis of sediment cores distributed along a transect from the upper slope to the abyssal plain. Spatial and temporal variations in sediment composition, sedimentation rate and turbidite frequency in late Pleistocene–Holocene time (last ∼20 14C ka) will be discussed and related to changes in sea level and climate, and tectonic activity.

This paper gives an overview of the structure and processes going on in the project Expert Systems for Chemical Analysis (ESCA), an international project within the ESPRIT research programme of the European Community. The application area, HPLC method development, is explained and broken down into four domains. The methods used for representing knowledge in the project are discussed.

A system for semiautomatic extraction of information from abstracts describing analytical methods is described. The system is based on the theory of Government and Binding for the syntactic part and Conceptual Graphs for the discourse analysis part. The system is modular and largely domain independent. The corpus of abstracts for which it is being developed contains abstracts from Analytical Abstracts Online. The current status of the system is that the grammar is finished and that the lexicon and the discourse module are under development. Preliminary results are that the system is capable of analyzing six abstracts on various analytical techniques.

Summary: A highly sensitive on-line amperometric detection of platinum compounds in HPLC effluents was possible with the use of a polarographic detector. For TNO-1 (=cis-1,1-di(aminomethyl)-cyclohexane Pt(II)chloride) a linear dynamic range of at least three decades could be obtained (0.034–108mgrg TNO-1/ml) with a detection limit of three times the noise signal at 0.7 ng TNO-1 (20ng Pt/ml). The sensitivity was 0.1 nA/ng TNO-1 (0.2nA/ng Pt). The within-day presicion was 1.1% at a concentration of 10.8mgrg TNO-1/ml (n=10). With this system the compatibility was measured of TNO-6 with infusion fluids. In 0.15 M NaCl, TNO-6 (=cis-1,1-di(aminomethyl)-cyclohexanePt(II)sulphate) was converted into TNO-1 within 40 minutes. Molecular changes of TNO-6 were also observed in a 5% aqueous glucose solution.

A system for semiautomatic extraction of information from abstracts describing analytical methods is described. The system is based on the theory of Government and Binding for the syntactic part and Conceptual Graphs for the discourse analysis part. The system is modular and largely domain independent. The corpus of abstracts for which it is being developed contains abstracts from Analytical Abstracts Online. The current status of the system is that the grammar is finished and that the lexicon and the discourse module are under development. Preliminary results are that the system is capable of analyzing six abstracts on various analytical techniques.

AimTo study the long term changes in the concentric contraction of the visual field in patients with temporal lobe epilepsy on vigabatrin medication.MethodsRepeated Goldmann visual field examinations were compared in 27 patients with drug resistant temporal lobe epilepsy and concentric contraction of the visual field. Two groups were studied: 16 patients who had already stopped vigabatrin medication before surgery and 11 patients who continued vigabatrin medication.ResultsConcentric contraction of the visual field did not change in 16 patients who stopped vigabatrin before the first examination; there was slight but significant progress in visual field loss in 11 patients who continued the use of vigabatrin.ConclusionLong term follow up of concentric contraction in this selected group of patients indicates that vigabatrin associated visual field loss is not reversible and that progression is possible when vigabatrin is continued.

Military personnel serving on active duty suffering from loud, bothersome snoring often require surgical treatment. This elective treatment should not disrupt the command and should have minimal impact on military readiness. Major drawbacks of the standard procedure, uvulopalatopharyngoplasty, include postoperative pain requiring convalescent leave, postoperative bleeding, and velopharyngeal incompetence. In addition, the surgery consumes limited operating room time for what many consider elective surgery. Sequential uvulopalatoplasty was developed as an alternative. This is performed with a carbon dioxide laser under local anesthesia in a clinic setting, but it requires cumbersome laser precautions and expensive laser equipment. Standard electrocautery can be used instead of a laser for this procedure. This avoids additional expense, special precautions, and equipment but is equally safe and effective. We compare time lost from work, duration and level of pain experienced, number of days until regular diet resumed, and effectiveness between uvulopalatopharyngoplasty and sequential uvulopalatoplasty. We found sequential uvulopalatoplasty to have less impact on military readiness while being as effective as uvulopalatopharyngoplasty for snoring. This makes it an ideal treatment modality for patients desiring surgical correction of snoring.