Simulation-Based Analysis of the Potential of Alternative Fuels towards Reducing CO2 Emissions from Aviation

The mid-term framework of global aviation is shaped by air travel demand growth rates of 2–5% p.a. and ambitious targets to reduce aviation-related CO2 emissions by up to 50% until 2050. Alternative jet fuels such as bio- or electrofuels can be considered as a potential means towards low-emission aviation. While these fuels offer significant emission reduction potential, their market success depends on manifold influencing factors like the maturity of the production technology or the development of the price of conventional jet fuel. To study the potential for adoption of alternative jet fuels in aviation and the extent to which alternative fuels can contribute to the reduction targets, we deploy a System Dynamics approach. The results indicate that the adoption of alternative fuels and therefore their potential towards low-emissions aviation is rather limited in most scenarios considered since current production processes do not allow for competitive prices compared to conventional jet fuel. This calls for the development of new production processes that allow for economic feasibility of converting biomass or hydrogen into drop-in fuels as well as political measures to promote the adoption of alternative fuels

PATHWAYS LINKING EARLY LIFE STRESS, METABOLIC SYNDROME, AND THE INFLAMMATORY MARKER FIBRINOGEN IN DEPRESSED INPATIENTS

Background: Previous research has shown that metabolic syndrome as well as early life stress can account for immunoactivation (e.g. in the form of altered fibrinogen levels) in patients with major depression. This study aims at assessing the relationship between components of metabolic syndrome, early life stress and fibrinogen levels, taking the severity of depression into consideration. Subjects and methods: Measures of early life stress and signs of metabolic syndrome were collected in 58 adult inpatients diagnosed with depression. The relationships between the factors were assessed by means of path analyses. Two main models were tested: the first model with metabolic syndrome mediating between early life stress and fibrinogen levels and the second model without the mediating effect of metabolic syndrome. Results: The first model was not supported by our data (χ²=7.02, df=1, p=0.008, CFI=0.00, NNFI=-9.44, RMSEA=0.50). The second model however provided an excellent fit for the data (χ²=0.02, df=1, p=0.90, CFI=1.00, NNFI=2.71, RMSEA=0.00). Extending the models by introducing severity of depression into them did not yield good indices of fit. Conclusions: The developmental trajectory between early life stress and inflammation appears not to be mediated by metabolic syndrome associated factors in our sample. Possible reasons including severity and type of early life stress, as well as potential epigenetic influences are discussed

Modulation of gene expression in U251 glioblastoma cells by binding of mutant p53 R273H to intronic and intergenic sequences

Missense point mutations in the TP53 gene are frequent genetic alterations in human tumor tissue and cell lines derived thereof. Mutant p53 (mutp53) proteins have lost sequence-specific DNA binding, but have retained the ability to interact in a structure-selective manner with non-B DNA and to act as regulators of transcription. To identify functional binding sites of mutp53, we established a small library of genomic sequences bound by p53R273H in U251 human glioblastoma cells using chromatin immunoprecipitation (ChIP). Mutp53 binding to isolated DNA fragments confirmed the specificity of the ChIP. The mutp53 bound DNA sequences are rich in repetitive DNA elements, which are dispersed over non-coding DNA regions. Stable down-regulation of mutp53 expression strongly suggested that mutp53 binding to genomic DNA is functional. We identified the PPARGC1A and FRMD5 genes as p53R273H targets regulated by binding to intronic and intra-genic sequences. We propose a model that attributes the oncogenic functions of mutp53 to its ability to interact with intronic and intergenic non-B DNA sequences and modulate gene transcription via re-organization of chromatin

Perceived risk of diabetes seriously underestimates actual diabetes risk: The KORA FF4 study.

OBJECTIVE:Early detection of diabetes and prediabetic states is beneficial for patients, but may be delayed by patients´ being overly optimistic about their own health. Therefore, we assessed how persons without known diabetes perceive their risk of having or developing diabetes, and we identified factors associated with perception of diabetes risk. RESEARCH DESIGN AND METHODS:1,953 participants without previously known diabetes from the population-based, German KORA FF4 Study (59.1 years, 47.8% men) had an oral glucose tolerance test. They estimated their probability of having undiagnosed diabetes mellitus (UDM) on a six category scale, and assessed whether they were at risk of developing diabetes in the future. We cross-tabulated glycemic status with risk perception, and fitted robust Poisson regression models to identify determinants of diabetes risk perception. RESULTS:74% (95% CI: 65-82) of persons with UDM believed that their probability of having undetected diabetes was low or very low. 72% (95% CI: 69-75) of persons with prediabetes believed that they were not at risk of developing diabetes. In people with prediabetes, seeing oneself at risk of diabetes was associated with self-rated poor general health (prevalence ratio (PR) = 3.1 (95% CI: 1.4-6.8), parental diabetes (PR = 2.6, 1.9-3.4), high educational level (PR = 1.9 (1.4-2.5)), lower age (PR = 0.7, 0.6-0.8, per 1 standard deviation increase), female sex (PR = 1.2, 0.9-1.5) and obesity (PR = 1.5, 1.2-2.0). CONCLUSIONS:People with undiagnosed diabetes or prediabetes considerably underestimate their probability of having or developing diabetes. Contrary to associations with actual diabetes risk, perceived diabetes risk was lower in men, lower educated and older persons