The Link Between Employees' Sense of Vitality and Proactivity:Investigating the Moderating Role of Personal Fear of Invalidity

Proactive behavior has emerged as a key component in contemporary views of individual work performance. Hence, a central question in the literature is how to enhance employees' proactive behavior. We investigated whether the more that employees experience a sense of vitality (i.e., energizing positive affect), the more likely they are to show proactive behavior at work, and whether this applies only to employees with a low personal fear of invalidity [(PFI) i.e., the inclination to be apprehensive about the risks/negative consequences of making errors]. Experimental (N= 354) and cross-sectional field (N= 85) studies provided consistent evidence for a positive relation between employees' sense of vitality at work and their self-rated proactivity. The predicted moderation effect was observed only for manager-rated proactivity. We conclude that feeling energized in the workplace is not necessarily associated with observable proactive behavior. It is only when employees experiencing a sense of vitality at work are not prone to fearing the risks/negative consequences of making errors that they are more likely to show observable proactive behavior in an organization

Whole-body MRI in children with langerhans cell histiocytosis for the evaluation of the skeletal system.

The usefulness of whole-body MRI (WB-MRI) for the detection of skeletal lesions in patients with Langerhans cell histiocytosis should be documented on the basis of case presentations. MATERIALS AND METHODS: In six patients with histologically proven Langerhans cell histiocytosis, 14 WB-MRI examinations were performed to evaluate the skeletal system within disease staging (6 primary, 8 follow-up examinations). The examinations were performed on a 1.5 Tesla, 32-channel whole-body scanner. The examination protocol consisted of T 1-weighted and STIR sequences in coronal and sagittal orientation. For comparison, radiographs of the initial skeletal lesions and those that were additionally detected on WB-MRI were available. RESULTS: In 4 patients no additional skeletal lesions were found on WB-MRI besides the initial lesion leading to the diagnosis of unifocal single system disease. In 2 patients WB-MRI was able to identify additional skeletal lesions. In a 5 S year-old boy with the primary lesion located in the cervical spine, a second lesion was detected in the lumbar spine on the initial scan and in the skull and proximal femur during follow-up examination. In a 12 year-old girl with a primary lesion of the thoracic spine, WB-MRI diagnosed additional lesions in the pelvic bone and the tibia. In both patients the diagnosis of multifocal skeletal involvement led to chemotherapy. During follow-up examination, the healing response under therapy could be demonstrated. Comparison with conventional imaging showed that especially lesions located in the spine or the pelvis were not detectable on radiographs even when knowing the MR results. CONCLUSION: The extent of skeletal involvement in Langerhans cell histiocytosis has crucial impact on therapy and prognosis. Whole-body MRI has been reported to be an established method for the evaluation of disseminated skeletal disease with distinct advantages over conventional radiography and bone scintigraphy. Our results suggest that WB-MRI should also be the imaging modality of choice for the assessment of skeletal involvement in children with Langerhans cell histiocytosis