The Postpartum Specific Anxiety Scale: development and preliminary validation

Perinatal symptoms of anxiety are increasingly recognised due to their high prevalence and impact. Studies using pregnancy-specific anxiety measures have found that they may predict perinatal outcomes more effectively than general measures. However, no such measure exists to assess anxieties specific to the postpartum. This study aimed to develop and validate a measure (Postpartum Specific Anxiety Scale; PSAS) that accurately represents the specific anxieties faced by postpartum women, using a four-stage methodology: (1) 51 items were generated from interviews conducted with a group of 19 postpartum women at two time points, (2) the scale was reviewed and refined by a diverse expert panel, (3) an online pilot study (n = 146) was conducted to assess comprehensibility and acceptability and (4) an online sample of 1282 mothers of infants up to 6 months old completed the PSAS against a battery of convergent measures. A subsample (n = 262) repeated the PSAS 2 weeks later. The PSAS possessed good face and content validity and was comprehensible and acceptable to postpartum women. PSAS scores were significantly correlated with other measures indicating good convergent validity. Principal component analyses (PCA) revealed a simple four-factor structure. Reliability of the overall scale and individual PSAS factors proved to be good to excellent. A preliminary receiver operating characteristic (ROC) analysis also suggested that the PSAS may be a useful screening tool. The psychometric evidence suggests that the PSAS is an acceptable, valid, and reliable research tool to assess anxieties, which are specific to the postpartum period. Next steps in the iterative validation process are considered for both research and screening purposes

Preparation and investigation of phthalocyanine C60 solar cells

Phthalocyanine C60 heterostructure organic solar cells were fabricated by evaporating highly purified materials under high vacuum conditions. 1 2.5 external power conversion efficiencies were obtained with ITO PEDOT PSS 300 ZnPc 300 C60 170 BCP Al layering. The role of the buffer layers at the interfaces to the electrodes and their influence on the I V characteristics was studied. Degradation of the organic cell caused by air and light exposure was investigated. Atmospheric oxygen diffusing into C60 films was identified as external source of degradation. A second source was spotted in the interior of the cel

Hydrogen in Nb and Nb/Ti/Nb Thin Films*

Epitaxial Nb and Nb Ti Nb films on sapphire substrates were prepared by e beam evaporation and sealed with thin Pd or Au layers to avoid oxidation. Hydrogen charging was performed from the gas phase and the concentration in the films was measured by the N 15 nuclear reaction method. For the single Nb layer the hydrogen concentration in the film as a function of the external hydrogen pressure solubility was investigated. For the Nb Ti Nb sandwich samples the distribution of hydrogen among the different layers was studied. In both cases deviations from the bulk behavior were observed. They are attributed to restrictions in the lateral expansion of epitaxial films. In addition interface effects were studie

Hydrogen in Nb and Nb Ti Nb thin films

Epitaxial Nb and Nb Ti Nb films on sapphire substrates were prepared by e beam evaporation and sealed with thin Pd or Au layers to avoid oxidation. Hydrogen charging was performed from the gas phase and the concentration in the films was measured by the N 15 nuclear reaction method. For the single Nb layer the hydrogen concentration in the film as a function of the external hydrogen pressure solubility was investigated. For the Nb Ti Nb sandwich samples the distribution of hydrogen among the different layers was studied. In both cases deviations from the bulk behavior were observed. They are attributed to restrictions in the lateral expansion of epitaxial films. In addition interface effects were studie