Fundamental spray and combustion measurements of soy methyl-ester biodiesel

Although biodiesel has begun to penetrate the fuel market, its effect on injection processes, combustion and emission formation under diesel engine conditions remains somewhat unclear. Typical exhaust measurements from engines running biodiesel indicate that particulate matter, carbon monoxide and unburnt hydrocarbons are decreased, whereas nitrogen oxide emissions tend to be increased. However, these observations are the result of complex interactions between physical and chemical processes occurring in the combustion chamber, for which understanding is still needed. To characterize and decouple the physical and chemical influences of biodiesel on spray mixing, ignition, combustion and soot formation, a soy methyl-ester (SME) biodiesel is injected into a constant-volume combustion facility under diesel-like operating conditions. A range of optical diagnostics is performed, comparing biodiesel to a conventional #2 diesel at the same injection and ambient conditions. Schlieren high-speed imaging shows virtually the same vapour-phase penetration for the two fuels, while simultaneous Mie-scatter imaging shows that the maximum liquid-phase penetration of biodiesel is higher than diesel. Differences in the liquid-phase penetration are expected because of the different boiling-point temperatures of the two fuels. However, the different liquid-phase penetration does not affect overall mixing rate and downstream vapour-phase penetration because each fuel spray has similar momentum and spreading angle. For the biodiesel and diesel samples used in this study, the ignition delay and lift-off length are only slightly less for biodiesel compared to diesel, consistent with the fuel cetane number (51 for biodiesel, 46 for diesel). Because of the similarity in lift-off length, the differences in equivalence ratio distribution at the lift-off length are mainly affected by the oxygen content of the fuels. For biodiesel, the equivalence ratio is reduced, which, along with the fuel molecular structure and oxygen content, significantly affects soot formation downstream. Spatially resolved soot volume fraction measurements obtained by combining line-of-sight laser extinction measurements with planar laser-induced incandescence imaging show that the soot concentration can be reduced by an order of magnitude for biodiesel. These integrated measurements of spray mixing, combustion and quantitative soot concentration provide new validation data for the development of computational fluid dynamics spray, combustion and soot formation models suitable for the latest biofuels.This work was supported by the Spanish Ministry of Science and Innovation for Jean-Guillaume Nerva's visiting research, through the OPTICOMB project [TRA2007-67961-C03-01].Nerva, J.; Genzale, CL.; Kook, S.; García Oliver, JM.; Pickett, LM. (2013). Fundamental spray and combustion measurements of soy methyl-ester biodiesel. 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A systematic review of non-antibiotic measures for the prevention of urinary tract infections in pregnancy

Background: Urinary tract infections (UTIs) are common in pregnancy and account for the highest proportion of primary care antibiotic prescriptions issued to pregnant women in the UK. It is well known that antibiotic use is associated with increased antimicrobial resistance and therefore measures to minimise antibiotic use for UTI prevention have been studied. The efficacy and safety of these measures in pregnancy have not been addressed and therefore the aim of this study was to systematically review the literature to identify and evaluate potential measures to prevent UTIs in pregnant women. Methods: Ten databases (EMBASE, AMED, BNI, CINAHL, Medline, PubMed, PsycINFO, Cochrane Trials, Scopus and Science Direct) were systematically searched in July 2017 for studies reporting non-antibiotic measures to prevent UTIs in pregnancy. The terms (“urinary tract infection”or UTI or bacteriuria or cystitis) AND (prevention) AND (pregnan*) were used. The quality of the publications was appraised using the Critical Appraisal Skills Programme (CASP) checklists for cohort study, case-control study and randomised controlled trial. The results were synthesised using a textual narrative approach. Results: Search results yielded 3276 publications and after reviewing titles and removing duplicates, 57 full text articles were assessed for eligibility and eight were included in the review. Five different approaches (hygiene measures, cranberry juice, immunisation, ascorbic acid and Canephron® N) have been identified, all of which are reported to be safe in pregnancy. Conclusion: The quality of the evidence varied considerably and only hygiene measures were supported by evidence to be recommended in practice. Future work needs to concentrate on strengthening the evidence base through improved design and reporting of studies with a focus on immunisation, ascorbic acid and Canephron® N

Clinical significance of stromal apoptosis in colorectal cancer

BackgroundEpithelial and stromal cells play an important role in the development of colorectal cancer (CRC). We aimed to determine the prognostic significance of both epithelial and stromal cell apoptosis in CRC.MethodsTotal apoptosis was determined by caspase-3 activity measurements in protein homogenates of CRC specimens and adjacent normal mucosa of 211 CRC patients. Epithelial apoptosis was determined by an ELISA specific for a caspase-3-degraded cytokeratin 18 product, the M30 antigen. Stromal apoptosis was determined from the ratio between total and epithelial apoptosis.ResultsEpithelial and stromal apoptosis, as well as total apoptosis, were significantly higher in CRC compared with corresponding adjacent normal mucosa. Low total tumour apoptosis (< or = median caspase-3 activity) was associated with a significantly worse disease recurrence (hazard ratio (HR), 95% confidence interval (95% CI): 1.77 (1.05-3.01)), independent of clinocopathological parameters. Epithelial apoptosis was not associated with clinical outcome. In contrast, low stromal apoptosis (< or = median caspase-3/M30) was found to be an independent prognostic factor for overall survival, disease-free survival and disease recurrence, with HRs (95% CI) of 1.66 (1.17-2.35), 1.62 (1.15-2.29) and 1.69 (1.01-2.85), respectively.InterpretationStromal apoptosis, in contrast to epithelial apoptosis, is an important factor with respect to survival and disease-recurrence in CRC

Hippocampal - diencephalic - cingulate networks for memory and emotion: An anatomical guide

This review brings together current knowledge from tract tracing studies to update and reconsider those limbic connections initially highlighted by Papez for their presumed role in emotion. These connections link hippocampal and parahippocampal regions with the mammillary bodies, the anterior thalamic nuclei, and the cingulate gyrus, all structures now strongly implicated in memory functions. An additional goal of this review is to describe the routes taken by the various connections within this network. The original descriptions of these limbic connections saw their interconnecting pathways forming a serial circuit that began and finished in the hippocampal formation. It is now clear that with the exception of the mammillary bodies, these various sites are multiply interconnected with each other, including many reciprocal connections. In addition, these same connections are topographically organised, creating further subsystems. This complex pattern of connectivity helps explain the difficulty of interpreting the functional outcome of damage to any individual site within the network. For these same reasons, Papez’s initial concept of a loop beginning and ending in the hippocampal formation needs to be seen as a much more complex system of hippocampal–diencephalic–cingulate connections. The functions of these multiple interactions might be better viewed as principally providing efferent information from the posterior medial temporal lobe. Both a subcortical diencephalic route (via the fornix) and a cortical cingulate route (via retrosplenial cortex) can be distinguished. These routes provide indirect pathways for hippocampal interactions with prefrontal cortex, with the preponderance of both sets of connections arising from the more posterior hippocampal regions. These multi-stage connections complement the direct hippocampal projections to prefrontal cortex, which principally arise from the anterior hippocampus, thereby creating longitudinal functional differences along the anterior–posterior plane of the hippocampus

Enrichment in vitamins

Vitamin concentration in hen feed is the most important factor in determining vitamin content in the egg. This is particularly true for fat-soluble vitamins. The lipid components of the egg, including fat-soluble vitamins, are only present in the yolk. During the last 10 days before hen ovulation, the lipids of dietary origin are absorbed and deposited in the yolk in the last phase of its formation. As the fat-soluble vitamin concentration of the feed increases, so does the vitamin content of the egg yolk. The most relevant data related to egg vitamin enrichment through nutrition are presented in this chapter, with special attention paid to vitamins E, A, and D. In particular the vitamin enrichment level reached in the egg and the implications on daily vitamin intake and consequently on consumer health are discussed