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Question: The European Food Safety Authority (EFSA) is responsible for risk assessment of all aspects of food safety, including the establishment of procedures aimed at the identification of emerging risks to food safety. Therefore, data from REACH registered substances were evaluated. Methods: Data available for REACH registered substances were evaluated by taking the following endpoints into account: (a) environmental release (derived from tonnage and ERC), (b) biodegradation (BIOWin predictions assessed in a battery approach), (c) bioaccumulation in food (modelled by ACC HUMANsteady) and (d) toxicity assessed by classification for mutagenicity, carcinogenicity, reprotoxicity and repeated dose toxicity. Two different approaches, weighting scenarios and Pivot table selections, were used to prioritise the potential of toxic chemicals to emerge in the food chain and, therefore, to represent a possible risk to food safety. Results: Of 2336 substances with relevant data, 212 were identified as priority substances for further evaluation. To confirm the accuracy of this prioritization, 10 chemicals were selected for in-depth evaluation of information on occurrence, analytical methods and toxicology. The selection focussed on chemicals that have not already been assessed in detail by other regulatory bodies and are not included in relevant lists (e.g. the Candidate List of the EU REACH Regulation). For 4 substances, data on the occurrence in the environment or in food/feed could be found. Enhanced monitoring in food/feed is recommended to better assess their relevance as emerging risks in the food chain. For the remaining 6 substances, no data on occurrence are available or existing data were considered uncertain. Conclusion: In cases, where no data are available, monitoring in relevant environmental compartments is recommended to gain more insight into their relevance as environmental contaminants. This study also identified 517 substances for which non-prioritisation solely depended on the fact that they are not classified for the relevant toxicological hazards. If such hazards are identified in the future, these substances would qualify as priority substances within the framework as established in this study.

The CFD investigations of distribution of emissions usually lack the validation aspect. This paper presents a benchmark test model which could be used as an effective and adequate validation tool for the CFD studies involving the different investigations of distribution of emissions in the indoor environment. The experiments were conducted using the full scale experimental test room. The time-dependent concentrations of propane and carbon dioxide at different locations inside the room were measured by flame ionization detectors and infrared photometers respectively. The Reynolds Averaged Navier Stokes equations of continuity, momentum, turbulence model (k-epsilon) and concentration were solved using ANSYS CFX 15.0. The simulation results and the experimental results were found to be in good agreement.

We describe the clinical course and outcome following decompressive craniectomy in six patients. Five patients suffered from severe intracranial hypertension due to middle cerebral artery infarction. In one patient the cause was bacterial meningoencephalitis. Acute clinical and neuroradiological signs of intracranial hypertension were seen in all cases. Following ineffective conventional brain edema therapy, decompressive craniectomy was undertaken. In five cases intracranial pressure was sufficiently lowered. One patient developed transtentorial herniation with subsequent brain death. Four patients with middle artery infarction showed moderate neurological disorders and one patient with bacterial meningoencephalitis recovered completely after treatment. Craniectomy in malignant middle artery infarction should be taken into consideration if conventional brain edema therapy does not sufficiently reduce critically raised intracranial pressure. Craniectomy provides development of brain herniation. This treatment may reduce high lethality rate and high frequency of severe neurological disorders.

A comprehensive infrared microscopic study of single tracks of atmospheric pressure plasma polymerised HMDSO is presented. The effects of different process parameters, i.e. the process gas, the nozzle setting (distance between discharge chamber and injection point of the monomer gas), and the nozzle speed, are investigated. It is shown that the chemical structure of singles tracks is not homogenous along the deposit. An increase of the oxygen content in the process gas or an increase of the excitation energy transferred to the monomer gas increase the relative content of SiOCH3 and SiOH units within the bulk polymer network. The deposition of superposed tracks is studied as well and it is revealed that the structure of the coating is changed compared to the first track.

In the present work, the first observation of strong resonance Raman optical activity (RROA) involving more that one resonant electronic state is reported. The chiral transition metal complex bis-(trifluoroacetylcamphorato) copper(II), abbreviated Cu(tfc)(2), exhibits both resonance Raman (RR) and RROA spectra with laser excitation at 532 nm. Vibrational assignments for this complex were carried out by comparing the non-RR spectra of Cu(tfc)(2) excited at 1024 nm to density functional theory (DFT) calculations. The theory of the single-electronic-state (SES) RROA is extended to the next simplest level of theory involving two resonant electronic states (TES) without interstate vibronic coupling as an aide to the interpretation of the observed TES-RROA spectra. Based on measured UV-vis electronic absorbance spectra and corresponding TD-DFT calculations, the most likely two states associated with the RROA spectra are identified.

On the ROA to somewhere: The first combined study of measured and computed Raman optical activity (ROA) of a transition metal complex under non-resonant scattering conditions is reported. ROA measurements of the two enantiomers of the dichloro[ethylenebis(4,5,6,7-tetrahydro-1-indenyl)] zirconium(IV) complex yield virtually mirror-image ROA spectra. The experimental spectra are directly comparable with predicted ROA spectra.

Splitting it up: Excellent agreement between the experimental and the quantum-chemically simulated Raman optical activity (ROA) spectrum of (+)-poly(trityl methacrylate) shows that the polymer backbone adopts a left-handed helical conformation while the trityl side groups display a left-handed propeller conformation. Thus ROA can be used to determine the complete structure of synthetic chiral polymers in solution.

Within the EFSA Article 36 project “European Tool Usual Intake” (ETUI) a workshop was organised in May 2010 where the different available models to calculate usual intake were presented and discussed. This report integrates the workshop background document, the presentations given by experts, and the discussions during the workshop. The purpose of the workshop was to evaluate existing statistical methods for estimating usual intake with respect to a number of criteria, so that the performance of each method on each criterion will be well understood after the workshop. The outcome of the workshop allows choices to be made for a European Tool Usual Intake, to be implemented in the remainder of the project. A starting document was provided to the participants of the workshop with up-to-date information on methods, data and criteria, as a basis for discussion. It was apparent from the workshop that there is not one optimal model for all cases, rather a toolbox approach is suitable. The choice of the most appropriate model has to be fine-tuned case by case. Criteria to be considered are related to data availability and data pre-processing (e.g. compatibility of existing data formats, need to handle complicating factors like food code conversion, left-censored data, processing factors, brand loyalty, pooling over multiple datasets), the appropriateness of modelling assumptions for frequencies and amounts modelling (e.g. level of conservatism, additivity assumption and data transformations, the need to model intake as a function of covariates, correlations), the usefulness to combine survey and food frequency questionnaire data, the need to model single food intake or diet-aggregated intake, the need to evaluate uncertainties, and the usefulness of implementations. For the short term, case studies will be performed based on issues relevant for EFSA panels. Results from the workshop and possibilities of using models to calculate usual intake were recently discussed during the 5th meeting of the EFSA Expert group on food consumption data. Currently only few EU Member States use this kind of models but there is a lot of interest in gaining experience with the usual intake modelling. Several requests were received concerning the possibility of having more information about the ETUI project and even the organisation of a future training. In conclusion, this interim report is considered by EFSA to be a good review of the different models used and presents the main challenges related to the use of these techniques. Its publication could be useful to those who want to start using this kind of methodology

Natural resonance electronic Raman optical activity (ROA) is observed forthe first time. Coincidently, the first example of vibrational ROA enhanced bylow-lying electronic transition is reported. These new phenomena were measuredusing the rare-earth complex Eu(tfc)3 (+)-tris[3- trifluoroacetyl-D-camphorato]europium(III), where electronic resonance occurs between the 532-nmlaser excitation and the 7F1 5D1 transition of the Eu3+ metal center. Electronic Ramanspectra involve the Raman transitions terminating on the low-lying electronicstates of Eu(tfc)3. The observed vibrational ROA spectra are enhancedrelative to typical ROA spectra by the proximity of vibrational states ofEu(tfc)3 to its low-lying electronic states with significantmagnetic-dipole character, whereas the parent vibrational Raman spectra do notappear to be resonance-enhanced since the 532-nm vibrational Raman spectrum hassimilar relative intensities to the corresponding Raman spectrum measured with1064-nm laser excitation.

Vibrational circular dichroism (VCD) spectroscopy and density functional theory (DFT) calculations are used to investigate the keto-enol equilibrium of 3( trifluoroacetyl)-camphor (TFC) and to study the interaction of TFC with chiral amines in deuterated Chloroform. It is shown that the VCD spectra of the enol-and keto forms of TFC can clearly be distinguished and that the enol form is favored. By deprotonation of the TFC enol with chiral amines, no indication of a mutual diasteriomeric influence on the VCD spectra induced by transfer of stereochemical information between the chiral ionic species is found, neither experimentally nor theoretically. Chirality 22: 772-777, 2010.

FTIR spectroscopic imaging is combined with linear dichroism measurements to investigate the structures of spherulites of poly(3-hydroxybutyrate) and isotactic poly(propylene oxide). It is shown that this technique can be used to easily gain qualitative information about relative orientations of chemical bonds within a solid polymeric sample. Furthermore the imaging technique is shown to have the considerable advantage that the obtained images are easy to understand and easy to interpret even without deep knowledge of FTIR linear dichroism measurements.

The present work provides a comprehensive theoretical and experimental study of the vibrational circular dichroism of (S)-alpha-phenylethyl isocyanide in chloroform. The structure in solution is investigated systematically by density functional theory calculations starting from the isolated molecule and then by considering solvent effects implicitly using the PCM and explicitly by taking into account molecular complexes of the isocyanide molecule and chloroform. Furthermore, the influence of dimerisation is evaluated, and it is finally found that the structure of (S)-alpha-phenylethyl isocyanide in chloroform is best described assuming a solvated dimer. These results are underlined by a quantitative correlation of the experimentally and theoretically obtained rotational strengths and a robust modes analysis.

Chiral alpha-methylbenzyl amine is a well known and often used chiral auxiliary, e. g., in the resolution of racemates or asymmetric catalysis. In this work, alpha-methylbenzyl amine and its derivatives N,alpha-dimethylbenzyl amine, N,N,alpha-trimethylbenzyl amine, and bis[alpha-methylbenzyl] amine were investigated by vibrational circular dichroism (VCD) spectroscopy and density functional theory (DFT). For all compounds, stable low energy conformers were obtained by the DFT calculations and based on those, the theoretical vibrational absorption (VA) and VCD spectra were calculated and compared with experimental spectra. Hence, the absolute configurations and conformational preferences were determined. A qualitative comparison of all the experimental VCD spectra of the investigated chiral molecules supported by the calculated ones is given which clearly shows similarities between the spectra of the different chiral amines. These can be assigned to vibrations of the unchanged chiral center. Chirality 22: 754-761, 2010.