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21.
This paper investigates what configurations of organization-level contingencies explain different performance management system (PMS) designs in project-based organizations (PBOs). By studying organization-level contingency factors – perceived environmental uncertainty, organizational size, innovation strategy, and opportunity strategy – this paper extends prior literature on PMSs in PBOs, which predominantly focused on project and portfolio level contingencies. In addition, while prior literature studied the contingency factors separately, this paper argues that it is the configuration of contingencies that matter for PMS design choices. Data on 15 PBOs in the management consulting industry reveal that PBOs combine various controls into performance management systems that are either predominantly mechanistic or organic in nature. Qualitative Comparative Analysis (QCA) points to four configurations of organization-level characteristics, two of which are associated with the PBO's choice for mechanistic performance management system, and two that are related to organic performance management system.  相似文献   
22.
In this report we explore the use of MALDI-FTICR mass spectrometry for the quantitative analysis of five HIV-1 protease inhibitors in cell lysates. 2,5-Dihydroxybenzoic acid (DHB) was used as the matrix. From a quantitative perspective, DHB is usually a poor matrix due to its poor shot-to-shot and poor spot-to-spot reproducibilities. We found that the quantitative precisions improved significantly when DMSO (dimethylsulfoxide) was added to the matrix solution. For lopinavir and ritonavir, currently the most frequently prescribed HIV-1 protease inhibitors, the signal-to-noise ratios improved significantly when potassium iodide was added to the matrix solution. The mean quantitative precisions, expressed as % relative standard deviation, were 6.4% for saquinavir, 7.3% for lopinavir, 8.5% for ritonavir, 11.1% for indinavir, and 7.2% for nelfinavir. The mean quantitative accuracies, expressed as % deviation, were 4.5% for saquinavir, 6.0% for lopinavir, 5.9% for ritonavir, 6.6% for indinavir, and 8.0% for nelfinavir. The concentrations measured for the individual quality control samples were all within 85-117% of the theoretical concentrations. The lower limits of quantification in cell lysates were 4 fmol/microL for saquinavir, 16 fmol/microL for lopinavir, 31 fmol/microL for ritonavir, and 100 fmol/microL for indinavir and nelfinavir. The mean mass accuracies for the protease inhibitors were 0.28 ppm using external calibration. Our results show that MALDI-FTICR mass spectrometry can be successfully used for precise, accurate, and selective quantitative analyses of HIV-1 protease inhibitors in cell lysates. In addition, the lower limits of quantification obtained allow clinical applications of the technique.  相似文献   
23.
Struvite crystallisation is a fast and reliable phosphorus removal and recovery process for concentrated waste streams - such as hydrolysed human urine. In order to optimise P-elimination efficiency, it is beneficial to obtain larger particle sizes: they are easier to separate and less prone to wash-out than smaller particles. This paper presents the results of a study on the effect of process parameters on particle size in a single step struvite precipitation. Crystals formed in batch experiments with real hydrolysed urine were shown to have an average size of >90 μm at pH 9 and 20 °C. This is reduced to 45 μm when changing stirrer type. Particle size increases with lower supersaturation. The results showed that under otherwise constant conditions, particle size decreases with lower temperature and has a minimum between pH 9 and 10. Deviating trends are observed at pH <8. Struvite formation in a CSTR (continuously stirred tank reactor) process was shown to be a reliable stable process that does not require any pH control. A method based on conductivity measurement is presented to estimate ionic strength, which is needed for equilibrium calculations.  相似文献   
24.
The current intervention study aimed at breaking the potential intergenerational cycle of insecure attachment. The authors randomly assigned 81 first-time mothers to one of two intervention groups or a control group. The interventions involved four home visits when the infants were between 7 and 10 months old. The first intervention, VIPP, consisted of video-feedback and brochures to enhance sensitive parenting. The second intervention, VIPP-R, involved additional discussions of mothers' childhood attachment experiences in relation to their current caregiving. After the intervention, intervention mothers were more sensitive than control mothers. The interventions were most effective for highly reactive children and their mothers, providing experimental support for Belsky's (1997) hypothesis of highly reactive versus less reactive children's evolutionary based differential susceptibility to rearing influences. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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