8 resultados para Ready-reckoners
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
Overcoming a crisis situation in which the socioemotional wealth (SEW) of a family is at risk can be threatened by a lack of formal crisis procedures, which can increase the probability of organizational decline. Thus, not being prepared for a crisis situation may be a critical factor in the long-term survival of family firms. From a corporate governance perspective, supervisory boards may achieve higher levels of crisis readiness. Applying the resourced-based view and SEW theory, we analyze the relationship between family ownership and formalized crisis procedures in 150 small and medium-sized German firms. Our results show that formalized crisis procedures decrease as family ownership increases. Including supervisory boards in our analysis, we find a significant moderating effect of supervisory boards on the relationship between family ownership and formalized crisis procedures. Specifically, our results suggest that family firms with supervisory boards show similar levels of formalized crisis procedures as non-family firms with supervisory boards. In contrast, family firms without supervisory boards exhibit lower levels of formalized crisis procedures compared with non-family firms without supervisory boards. We also discuss managerial implications, limitations, and future research.
Resumo:
Owing to its optimal nuclear properties, ready availability, low cost and favourable dosimetry, (99m)Tc continues to be the ideal radioisotope for medical-imaging applications. Bifunctional chelators based on a tetraamine framework exhibit facile complexation with Tc(V)O(2) to form monocationic species with high in vivo stability and significant hydrophilicity, which leads to favourable pharmacokinetics. The synthesis of a series of 1,4,8,11-tetraazaundecane derivatives (01-06) containing different functional groups at the 6-position for the conjugation of biomolecules and subsequent labelling with (99m)Tc is described herein. The chelator 01 was used as a starting material for the facile synthesis of chelators functionalised with OH (02), N(3) (04) and O-succinyl ester (05) groups. A straightforward and easy synthesis of carboxyl-functionalised tetraamine-based chelator 06 was achieved by using inexpensive and commercially available starting materials. Conjugation of 06 to a potent bombesin-antagonist peptide and subsequent labelling with (99m)Tc afforded the radiotracer (99m)Tc-N4-BB-ANT, with radiolabelling yields of >97% at a specific activity of 37 GBq micromol(-1). An IC(50) value of (3.7+/-1.3) nM was obtained, which confirmed the high affinity of the conjugate to the gastrin-releasing-peptide receptor (GRPr). Immunofluorescence and calcium mobilisation assays confirmed the strong antagonist properties of the conjugate. In vivo pharmacokinetic studies of (99m)Tc-N4-BB-ANT showed high and specific uptake in PC3 xenografts and in other GRPr-positive organs. The tumour uptake was (22.5+/-2.6)% injected activity per gram (% IA g(-1)) at 1 h post injection (p.i.). and increased to (29.9+/-4.0)% IA g(-1) at 4 h p.i. The SPECT/computed tomography (CT) images showed high tumour uptake, clear background and negligible radioactivity in the abdomen. The promising preclinical results of (99m)Tc-N4-BB-ANT warrant its potential candidature for clinical translation.
Resumo:
Three-dimensional rotational X-ray imaging with the SIREMOBIL Iso-C3D (Siemens AG, Medical Solutions, Erlangen, Germany) has become a well-established intra-operative imaging modality. In combination with a tracking system, the Iso-C3D provides inherently registered image volumes ready for direct navigation. This is achieved by means of a pre-calibration procedure. The aim of this study was to investigate the influence of the tracking system used on the overall navigation accuracy of direct Iso-C3D navigation. Three models of tracking system were used in the study: Two Optotrak 3020s, a Polaris P4 and a Polaris Spectra system, with both Polaris systems being in the passive operation mode. The evaluation was carried out at two different sites using two Iso-C3D devices. To measure the navigation accuracy, a number of phantom experiments were conducted using an acrylic phantom equipped with titanium spheres. After scanning, a special pointer was used to pinpoint these markers. The difference between the digitized and navigated positions served as the accuracy measure. Up to 20 phantom scans were performed for each tracking system. The average accuracy measured was 0.86 mm and 0.96 mm for the two Optotrak 3020 systems, 1.15 mm for the Polaris P4, and 1.04 mm for the Polaris Spectra system. For the Polaris systems a higher maximal error was found, but all three systems yielded similar minimal errors. On average, all tracking systems used in this study could deliver similar navigation accuracy. The passive Polaris system showed ? as expected ? higher maximal errors; however, depending on the application constraints, this might be negligible.
Resumo:
Soil erosion on sloping agricultural land poses a serious problem for the environment, as well as for production. In areas with highly erodible soils, such as those in loess zones, application of soil and water conservation measures is crucial to sustain agricultural yields and to prevent or reduce land degradation. The present study, carried out in Faizabad, Tajikistan, was designed to evaluate the potential of local conservation measures on cropland using a spatial modelling approach to provide decision-making support for the planning of spatially explicit sustainable land use. A sampling design to support comparative analysis between well-conserved units and other field units was established in order to estimate factors that determine water erosion, according to the Revised Universal Soil Loss Equation (RUSLE). Such factor-based approaches allow ready application using a geographic information system (GIS) and facilitate straightforward scenario modelling in areas with limited data resources. The study showed first that assessment of erosion and conservation in an area with inhomogeneous vegetation cover requires the integration of plot-based cover. Plot-based vegetation cover can be effectively derived from high-resolution satellite imagery, providing a useful basis for plot-wise conservation planning. Furthermore, thorough field assessments showed that 25.7% of current total cropland is covered by conservation measures (terracing, agroforestry and perennial herbaceous fodder). Assessment of the effectiveness of these local measures, combined with the RUSLE calculations, revealed that current average soil loss could be reduced through low-cost measures such as contouring (by 11%), fodder plants (by 16%), and drainage ditches (by 53%). More expensive measures such as terracing and agroforestry can reduce erosion by as much as 63% (for agroforestry) and 93% (for agroforestry combined with terracing). Indeed, scenario runs for different levels of tolerable erosion rates showed that more cost-intensive and technologically advanced measures would lead to greater reduction of soil loss. However, given economic conditions in Tajikistan, it seems advisable to support the spread of low-cost and labourextensive measures.