219 research outputs found
Inequality at Work: The Effect of Peer Salaries on Job Satisfaction
We use a simple theoretical framework and a randomized manipulation of access to information on peers' wages to provide new evidence on the effects of relative pay on individual job satisfaction and job search intentions. A randomly chosen subset of employees of the University of California (UC) was informed about a new website listing the pay of University employees. All employees were then surveyed about their job satisfaction and job search intentions. Our information treatment doubles the fraction of employees using the website, with the vast majority of new users accessing data on the pay of colleagues in their own department. We find an asymmetric response to the information treatment: workers with salaries below the median for their pay unit and occupation report lower pay and job satisfaction, while those earning above the median report no higher satisfaction. Likewise, below-median earners report a significant increase in the likelihood of looking for a new job, while above-median earners are unaffected. Our findings suggest that job satisfaction depends directly on relative pay comparisons, and that this relationship is non-linear.
Similarity Maximization of a Scaled Aeroelastic Flight Demonstrator via Multidisciplinary Optimization
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143025/1/6.2017-0573.pd
Disrupted functional connectivity in adolescent obesity
Background/objective: Obesity has been associated with brain alterations characterised by poorer interaction between a hypersensitive reward system and a comparatively weaker prefrontal-cognitive control system. These alterations may occur as early as in adolescence, but this notion remains unclear, as no studies so far have examined global functional connectivity in adolescents with excess weight. Subjects/methods: We investigated functional connectivity in a sample of 60 adolescents with excess weight and 55 normal weight controls. We first identified parts of the brain displaying between-group global connectivity differences and then characterised the extent of the differences in functional network integrity and their association with reward sensitivity. Results: Adolescent obesity was linked to neuroadaptations in functional connectivity within brain hubs linked to interoception (insula), emotionalmemory (middle temporal gyrus) and cognitive control (dorsolateral prefrontal cortex) (pFWE < 0.05). The connectivity between the insula and the anterior cingulate cortex was reduced in comparison to controls, as was the connectivity between the middle temporal gyrus and the posterior cingulate cortex and cuneus/precuneus (pFWE < 0.05). Conversely, the middle temporal gyrus displayed increased connectivity with the orbitofrontal cortex (pFWE < 0.05). Critically, these networks were correlated with sensitivity to reward (p < 0.05). Conclusions: These findings suggest that adolescent obesity is linked to disrupted functional connectivity in brain networks relevant to maintaining balance between reward, emotional memories and cognitive control. Our findings may contribute to reconceptualization of obesity as a multi-layered brain disorder leading to compromised motivation and control, and provide a biological account to target prevention strategies for adolescent obesity
IL-6 Deficiency Attenuates Murine Diet-Induced Non-Alcoholic Steatohepatitis
BACKGROUND:The role of inflammation in the pathogenesis of non-alcoholic steatohepatitis (NASH), a common cause of liver disease, is still poorly understood. This study aimed at assessing the involvement of a major inflammatory cytokine, IL-6, in NASH. MATERIALS AND METHODS:Steatohepatitis was induced by feeding wild-type or IL-6(-/-) mice for 5 weeks with a methionine and choline-deficient (MCD) diet. RESULTS:Whereas MCD diet-induced weight loss and decreases in serum glucose, cholesterol and triglyceride levels were similar in both genotypes, serum alanine aminotransferase was less elevated in IL-6(-/-) mice than in wild-type animals. Despite having a comparable liver steatosis score, IL-6-deficient mice exhibited less lobular inflammation than their wild-type littermates. Liver gene expression of TGF-beta and MCP-1 was also strongly attenuated in mutant mice; a more modest reduction was observed for PPAR-gamma and F4/80 transcripts as well as proteins. Chromatographic analysis of liver lipids demonstrated that MCD diet induced in normal and mutant mice a similar decrease in the ratio of phosphatidylcholine to phosphatidylethanolamine. However, the diet-induced increase in the levels of sphingomyelin and ceramide was less important in IL-6(-/-) mice. CONCLUSION:Altogether, these results indicate that IL-6 deficiency does not block the development of NASH; yet, IL-6 plays a critical role in the accompanying liver inflammation
Antioxidant Potential is Correlated to ω6 / ω3 Ratio and Brasfield Score in Cystic Fibrosis Children
International audienceOBJECTIVES:Oxidative stress is associated with the condition of cystic fibrosis (CF), but no guidelines exist for its assessment or treatment. Our aim was to evaluate a test that measures the blood antioxidant capability in CF children.METHODS:This antioxidant capability was assessed by the Kit Radicaux Libres (KRL) test in 44 CF children (24 boys). We recorded also anthropometric measures, pulmonary function, CF severity scores, and plasma nutritional and inflammatory parameters (proteins, vitamins, erythrocyte fatty acids, and micronutrients). We performed univariate and multivariate analyses with linear regression models.RESULTS:The mean age at the first KRL assessment was 12.2 ± 3.8 years. Factors that correlated with decreased antioxidant capacity were mostly related to the severity of pulmonary disease [ forced expiratory volume at 1 second (FEV1), acute exacerbation, and congestion. In multivariate analysis, the correlation between Brasfield score and erythrocyte antioxidant potential remained significant (β = - 0.611, p < 0.001). Among nutritional factors, the ω6/ω3 ratio was significantly correlated to erythrocyte antioxidant potential (β = - 1.213, p = 0.01).CONCLUSION:The blood antioxidant capability, measured by the KRL test, appears to be an interesting biomarker to evaluate oxidative stress in CF. This study suggests that the ω6/ω3 ratio should be regarded as a nutritional marker in antioxidant management in CF children
Oxidative Phosphorylation Fueled by Fatty Acid Oxidation Sensitizes Leukemic Stem Cells to Cold
Dependency on mitochondrial oxidative phosphorylation (OxPhos) is a potential weakness for leukemic stem cells (LSC) that can be exploited for therapeutic purposes. Fatty acid oxidation (FAO) is a crucial OxPhos-fueling catabolic pathway for some acute myeloid leukemia (AML) cells, particularly chemotherapy-resistant AML cells. Here, we identified cold sensitivity at 4â—¦C (cold killing challenge; CKC4), commonly used for sample storage, as a novel vulnerability that selectively kills AML LSCs with active FAO-supported OxPhos while sparing normal hematopoietic stem cells. Cell death of OxPhos-positive leukemic cells was induced by membrane permeabilization at 4â—¦C; by sharp contrast, leukemic cells relying on glycolysis were resistant. Forcing glycolytic cells to activate OxPhos metabolism sensitized them to CKC4. Lipidomic and proteomic analyses showed that OxPhos shapes the composition of the plasma membrane and introduces variation of 22 lipid subfamilies between cold-sensitive and cold-resistant cells. Together, these findings indicate that steady-state energy metabolism at body temperature predetermines the sensitivity of AML LSCs to cold temperature, suggesting that cold sensitivity could be a potential OxPhos biomarker. These results could have important implications for designing experiments for AML research to avoid cell storage at 4â—¦C.</p
Disrupted functional connectivity in adolescent obesity.
BACKGROUND/OBJECTIVE: Obesity has been associated with brain alterations characterised by poorer interaction between a hypersensitive reward system and a comparatively weaker prefrontal-cognitive control system. These alterations may occur as early as in adolescence, but this notion remains unclear, as no studies so far have examined global functional connectivity in adolescents with excess weight. SUBJECTS/METHODS: We investigated functional connectivity in a sample of 60 adolescents with excess weight and 55 normal weight controls. We first identified parts of the brain displaying between-group global connectivity differences and then characterised the extent of the differences in functional network integrity and their association with reward sensitivity. RESULTS: Adolescent obesity was linked to neuroadaptations in functional connectivity within brain hubs linked to interoception (insula), emotional memory (middle temporal gyrus) and cognitive control (dorsolateral prefrontal cortex) (pFWE < 0.05). The connectivity between the insula and the anterior cingulate cortex was reduced in comparison to controls, as was the connectivity between the middle temporal gyrus and the posterior cingulate cortex and cuneus/precuneus (pFWE < 0.05). Conversely, the middle temporal gyrus displayed increased connectivity with the orbitofrontal cortex (pFWE < 0.05). Critically, these networks were correlated with sensitivity to reward (p < 0.05). CONCLUSIONS: These findings suggest that adolescent obesity is linked to disrupted functional connectivity in brain networks relevant to maintaining balance between reward, emotional memories and cognitive control. Our findings may contribute to reconceptualization of obesity as a multi-layered brain disorder leading to compromised motivation and control, and provide a biological account to target prevention strategies for adolescent obesity
Bacterial colonization status of cystic fibrosis children's toothbrushes: a pilot study
Pseudomonas aeruginosa and Staphylococcus aureus toothbrush contamination in cystic fibrosis (CF) is unknown. This pilot study aimed to determine their prevalence and the potential involvement of toothbrushes in pulmonary infection. Methods. Toothbrush bacteriological analysis for children aged 8–18 years was conducted on 27 CF patients, 15 healthy siblings, and 15 healthy children from the general population. Results : S. aureus was detected on 22% of the patients’ toothbrushes, and 13% of healthy children's toothbrushes and P. aeruginosa on 15% of patients’ toothbrushes and 0–13% of healthy children's toothbrushes. There was no statistical correlation between pulmonary colonization and toothbrush contamination. P. aeruginosa genotyping showed two identical clones on the patients’ toothbrushes and in their sputum, and between one patient's sputum and his sibling's toothbrush. Conclusion : S. aureus and P. aeruginosa can colonize CF patients’ toothbrushes. The impact on pulmonary colonization remains unknown. Toothbrush decontamination methods need to consider these bacteria in CF patients
- …