An overview of advances in biomass gasification

Biomass gasification is a widely used thermochemical process for obtaining products with more value and potential applications than the raw material itself. Cutting-edge, innovative and economical gasification techniques with high efficiencies are a prerequisite for the development of this technology. This paper delivers an assessment on the fundamentals such as feedstock types, the impact of different operating parameters, tar formation and cracking, and modelling approaches for biomass gasification. Furthermore, the authors comparatively discuss various conventional mechanisms for gasification as well as recent advances in biomass gasification. Unique gasifiers along with multi-generation strategies are discussed as a means to promote this technology into alternative applications, which require higher flexibility and greater efficiency. A strategy to improve the feasibility and sustainability of biomass gasification is via technological advancement and the minimization of socio-environmental effects. This paper sheds light on diverse areas of biomass gasification as a potentially sustainable and environmentally friendly technology

Complex Mortgages

We investigate the characteristics and the default behavior of households who take out complex mortgages. Unlike traditional fixed rate or adjustable rate mortgages, complex mortgages are not fully amortizing and enable households to postpone loan repayment. We find that complex mortgages are used by sophisticated households with high income levels and prime credit scores, in contrast to the low income population targeted by subprime mortgages. Complex mortgage borrowers have significantly higher delinquency rates than traditional mortgage borrowers even after controlling for leverage, payment resets, and other household and loan characteristics. The difference in the delinquency rates between complex and traditional borrowers increases with measures of financial sophistication and leverage, suggesting that complex borrowers are more strategic in their default decisions than traditional borrowers.

Cross-study Validation and Combined Analysis of Gene Expression Microarray Data

Investigations of transcript levels on a genomic scale using hybridization-based arrays led to formidable advances in our understanding of the biology of many human illnesses. At the same time, these investigations have generated controversy, because of the probabilistic nature of the conclusions, and the surfacing of noticeable discrepancies between the results of studies addressing the same biological question. In this article we present simple and effective data analysis and visualization tools for gauging the degree to which the finding of one study are reproduced by others, and for integrating multiple studies in a single analysis. We describe these approaches in the context of studies of breast cancer, and illustrate that it is possible to identify a substantial, biologically relevant subset of the human genome within which hybridization results are reproducible. The subset generally varies with the platforms used, the tissues studied, and the populations being sampled. Despite important differences, it is also possible to develop simple expression measures that allow comparison across platforms, studies, labs and populations. Important biological signal is often preserved or enhanced. Cross-study validation and combination of microarray results requires careful, but not overly complex, statistical thinking, and can become a routine component of genomic analysis

Plasma PGE-2 levels and altered cytokine profiles in adherent peripheral blood mononuclear cells in non-small cell lung cancer (NSCLC)

INTRODUCTION: PGE-2 is constitutively produced by many non-small cell lung cancers (NSCLC) and its immunosuppressive effects have been linked to altered immune responses in lung cancer. We asked whether elevated levels of plasma PGE-2 correlated with monocyte IL10 production in the NSCLC environment. Looking for correlation in NSCLC patient blood we assayed plasma from NSCLC patients for PGE2 and IL10; we further evaluated production of IL10 by adherent mononuclear cells from a subset of these patients looking for an altered cytokine profile. RESULTS: Our initial in vitro experiments show that monocyte IL10 induction correlates with tumor cell PGE-2 production, confirming similar reports in the literature. Data show plasma PGE-2 levels in 38 NSCLC patients are elevated compared to normal controls. Plasma IL10 levels were not significantly elevated; however, adherent monocytes derived from NSCLC patient blood did produce significantly more IL10 in 24 hr primary culture than those from normal controls (p < 0.01). The association of elevated plasma PGE-2 and monocyte derived IL-10 was not significant. CONCLUSIONS: Elevated plasma PGE-2 and monocyte IL10 production are associated with NSCLC. The biological significance to elevated PGE-2 levels in NSCLC are unclear. Further investigation of each as a nonspecific marker for NSCLC tumor is warranted

Elevated level of cell-free plasma DNA is associated with breast cancer

Background: We analysed cell-free DNA (cfDNA) in the plasma of patients with both malignant and benign breast lesions by real-time quantitative PCR to determine whether the finding may have diagnostic and prognostic implications. Methods: Plasma samples were obtained from 33 patients with breast cancer, 32 patients with benign breast lesions and 50 healthy women as normal controls. Circulatory cfDNA was extracted from the plasma samples and quantified by real-time quantitative PCR for the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene. Results: The mean concentrations of cfDNA in the plasma samples from patients with breast cancer, patients with benign breast lesions and normal controls were 2,285, 1,368 and 1,489 genome equivalents (GE) per millilitre, respectively. The level of cfDNA in the breast cancer group was significantly higher than those in the benign lesion group and control group (P=0.007 and 0.013, respectively). These findings were associated with malignant tumour size. The levels of the cfDNA were high in patients with lymph node involvement and distant metastasis. Conclusions: Our results suggest that levels of cfDNA in the plasma are elevated in malignant breast cancer and correlated with tumour size. These findings could have diagnostic and prognostic value for malignant breast tumour

Noninvasive vagus nerve stimulation alters neural response and physiological autonomic tone to noxious thermal challenge.

The mechanisms by which noninvasive vagal nerve stimulation (nVNS) affect central and peripheral neural circuits that subserve pain and autonomic physiology are not clear, and thus remain an area of intense investigation. Effects of nVNS vs sham stimulation on subject responses to five noxious thermal stimuli (applied to left lower extremity), were measured in 30 healthy subjects (n = 15 sham and n = 15 nVNS), with fMRI and physiological galvanic skin response (GSR). With repeated noxious thermal stimuli a group × time analysis showed a significantly (p &lt; .001) decreased response with nVNS in bilateral primary and secondary somatosensory cortices (SI and SII), left dorsoposterior insular cortex, bilateral paracentral lobule, bilateral medial dorsal thalamus, right anterior cingulate cortex, and right orbitofrontal cortex. A group × time × GSR analysis showed a significantly decreased response in the nVNS group (p &lt; .0005) bilaterally in SI, lower and mid medullary brainstem, and inferior occipital cortex. Finally, nVNS treatment showed decreased activity in pronociceptive brainstem nuclei (e.g. the reticular nucleus and rostral ventromedial medulla) and key autonomic integration nuclei (e.g. the rostroventrolateral medulla, nucleus ambiguous, and dorsal motor nucleus of the vagus nerve). In aggregate, noninvasive vagal nerve stimulation reduced the physiological response to noxious thermal stimuli and impacted neural circuits important for pain processing and autonomic output