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The results of studying the electronic states of the conduction band and interface potential barrier during the formation of ultrathin films of thiophene-phenylene co-oligomer CH3-phenylene-thiophene-thiophene-phenylene -CH3(CH3-PTTP-CH3) on the surface of ZnO and films of biphenyl tetracarboxylic dianhydride (BPDA) on the ZnO surface are presented. A 100 nm thick ZnO layer was prepared by atomic layer deposition (ALD). Organic CH3-PTTP-CH3 films and BPDA films up to 8 nm thick were formed by thermal vacuum deposition. During film deposition, the electronic characteristics of the surface were studied using total current spectroscopy (TCS) in the energy range from 5 eV to 20 eV above EF. In this energy range, the structure of the maxima of the unoccupied electronic states of CH3-PTTP-CH3 and BPDA films was determined. As a result of the CH3-PTTP-CH3 film deposition, a decrease in the work function to 4.0 eV was found, compared with the value of the work function of 4.2 eV measured from the ALD ZnO-substrate. This corresponds to the transfer of a negative charge from the CH3-PTTP-CH3 film to the substrate. The charge transfer at the interface between the BPDA film and the ALD ZnO-substrate occurs in the opposite direction, since a 4.7 eV increase of the work function was registered during the formation of this interface. The CH3-PTTP-CH3 and BPDA films studied and the layer-by-layer grown ZnO film represent a continuous coating on sufficiently large surface areas of the order of 10 μmx10 μm. The roughness of the ZnO surface does not exceed 4 nm, and the surface roughness of CH3-PTTP-CH3 and BPDA films was 10-15 nm. Keywords: thiophene-phenylene co-oligomers, biphenyl tetracarboxylic dianhydride, ultrathin films, ZnO, atomic layer deposition method, electronic properties, low-energy electron spectroscopy, interface potential barrier.

Jennifer M Stephens,1 Bonnie Handke,2 Jalpa A Doshi3 On behalf of the HTA Principles Working Group, part of the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) HTA Special Interest Group (SIG)1Pharmerit International, Bethesda, MD, USA; 2Medtronic Neuromodulation, Minneapolis, MN, USA; 3Center for Evidence-Based Practice and Center for Health Incentives and Behavioral Economics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USAObjective: To describe research methods used internationally in health technology assessment (HTA) and health-care reimbursement policies; compare the survey findings on research methods and processes to published HTA principles; and discuss important issues/trends reported by HTA bodies related to current research methods and applications of the HTA process.Methods: Representatives from HTA bodies worldwide were recruited to complete an online survey consisting of 47 items within four topics: (1) organizational information and process, (2) primary HTA methodologies and importance of attributes, (3) HTA application and dissemination, and (4) quality of HTA, including key issues. Results were presented as a comparison of current HTA practices and research methods to published HTA principles.Results: The survey was completed by 30 respondents representing 16 countries in five major regions, Australia (n = 3), Canada (n = 2), Europe (n = 17), Latin America (n = 2), and the United States (n = 6). The most common methodologies used were systematic review, meta-analysis, and economic modeling. The most common attributes evaluated were effectiveness (more commonly than efficacy), cost-effectiveness, safety, and quality of life. The attributes assessed, relative importance of the attributes, and conformance with HTA principles varied by region/country. Key issues and trends facing HTA bodies included standardizing methods for economic evaluations and grading of evidence, lack of evidence, and data availability for emerging technologies.Conclusion: This is the first international survey to specifically assess the state of HTA research methods. Future efforts should expand the respondent sample to include more emerging markets and update the results of this survey to specifically address additional aspects of research methods in HTA.Keywords: survey, technology assessment, payers, research methods, reimbursement

This paper presents experimental and theoretical studies of lattice vibrations in a single-crystalline Fe3O4(001) thin film. The investigations were carried out in order to see how the lattice dynamics changes at the Verwey transition. Vibrational densities of states (DOS) were obtained from nuclear inelastic scattering (NIS) of synchrotron radiation in the temperature range 25 to 296 K, while theoretical DOS were calculated ab initio within density functional theory. Experimental phonon density of states shows good agreement with calculated DOS, reproducing both the general features of main line groups as well as the groups' structure. This is also in qualitative accord with heat capacity data, provided that experimental DOS is augmented with that calculated for oxygen atoms. We have observed a gradual change in the NIS raw data as well as the relevant DOS while lowering the temperature. In particular, the main peak in the energy region 15-25 meV shows increasing splitting on cooling. The Lamb-Mossbauer factor calculated in the course of DOS evaluation shows a pronounced drop in the vicinity of the Verwey transition that may be partly connected to the observed abrupt lowering of the count rate at approximately 7 meV for T