Search results

Filter

Filetype

Your search for "*" yielded 529972 hits

Influence of wall ribs on the thermal stratification and self-pressurization in a cryogenic liquid tank

Self-pressurization in a cylindrical ribbed tank which is partially filled with liquid hydrogen is investigated numerically under different rib spacing-to-height ratios. The Volume of Fluid (VOF) method is employed as well as a phase change model. Appropriate models are incorporated into the Ansys Fluent by the user-defined functions to carry out the computations. The ribbed surface is modeled as

A European summertime CO2 biogenic flux inversion at mesoscale from continuous in situ mixing ratio measurements

A regional variational inverse modeling system for the estimation of European biogenic CO2 fluxes is presented. This system is based on a 50 km horizontal resolution configuration of a mesoscale atmospheric transport model and on the adjoint of its tracer transport code. It exploits hourly CO2 in situ data from 15 CarboEurope-Integrated Project stations. Particular attention in the inversion setup

Fermentation of the Straw Material Paja Brava by the Yeast Pichia stipitis in a Simultaneous Saccharification and Fermentation Process

Paja Brava is a native South American grass with a high carbohydrate content. In the current work, the potential of us- ing this feedstock for ethanol production using a simultaneous saccharification and fermentation (SSF) process with the xylose-fermenting yeast Pichia stipitis (Scheffersomyces stipitis) CBS6054 was investigated. The straw material was subjected to SO2 catalyzed steam pretreatmen

M4 Muscarinic Receptor Signaling Ameliorates Striatal Plasticity Deficits in Models of L-DOPA-Induced Dyskinesia.

A balanced interaction between dopaminergic and cholinergic signaling in the striatum is critical to goal-directed behavior. But how this interaction modulates corticostriatal synaptic plasticity underlying learned actions remains unclear-particularly in direct-pathway spiny projection neurons (dSPNs). Our studies show that in dSPNs, endogenous cholinergic signaling through M4 muscarinic receptors

Genetic analysis shows that Rubus vikensis is a distinct species with a disjunct distribution

Rubus vikensis A. Pedersen ex G. Wendt (sect. Corylifolii) was recently described from a restricted area in north western Scania, Sweden. In this investigation, I show that the same species occurs also on the Onsala peninsula in northern Halland and on a single locality in the middle of Halland. It has 35 chromosomes in all parts of the distribution area. Moreover, I show by random amplified polym

Management of bleeding disorders in children

Haemophilia, if not properly managed, can lead to chronic disease and lifelong disabilities. The challenges and issues in infants/young children are different from those in older children and adults although episodes of bleeding still predominate as the diagnostic trigger. Awareness of clinical manifestations and treatment complications are crucial in instituting appropriate management and impleme

Structure and function of chitinases from glycoside hydrolase family 19

Glycoside hydrolase family 19 chitinases are found in plants, bacteria and viruses, playing various roles. Plant chitinases are important for defence and development, whereas bacterial examples are useful for nutrition. The available structural studies show that family 19 enzymes are highly alpha-helical bi-lobed structures with a wide cleft lined by conserved residues important for catalysis and

Gas in scattering media absorption spectroscopy - from basic studies to biomedical applications

The recently introduced Gas in Scattering Media Absorption Spectroscopy (GASMAS) technique provides novel possibilities for analysis in biophotonics. Free gas in pores or cavities is monitored with narrow-band laser radiation, which can discern the gas absorptive imprints which are typically several orders of magnitude more narrow than the features of the surrounding tissue through which the diffu

Assessing the differences between the IntCal and Greenland ice-core time scales for the last 14,000 years via the common cosmogenic radionuclide variations

Variations in galactic cosmic rays reaching the Earth's atmosphere produce globally synchronous variations in the production rates of cosmogenic radionuclides. In consequence, they leave their imprint in tree-ring 14C and ice-core 10Be records. By identifying this signal and correcting for the known geochemical influences on the radionuclides, it is possible to compare and synchronize the tree-rin

Lawyers in Venture Capital Contracting: Theory and Evidence

Real-world financial contracts are sometimes so complex that it can be difficult to understand their exact payoff consequences. We develop and test a theoretical model of a venture capitalist (VC) negotiating with an entrepreneur who may overweigh or underweigh the payoff consequences of contractual downside protection (DP). A lawyer with expertise in venture capital can inform the entrepreneur ab

Controlled feeding of cellulases improves conversion of xylose in simultaneous saccharification and co-fermentation for bioethanol production.

Simultaneous saccharification and fermentation (SSF) is an interesting option for ethanol production from lignocellulosic materials. To meet desired overall yields during ethanol production from lignocellulosic materials, it is important to use both hexoses and pentoses. This can be achieved by co-fermentation of sugars in SSF, so called SSCF (simultaneous saccharification and co-fermentation), us

The Endurance/Perdurance Controversy is No Storm in a Teacup

Several philosophers have maintained in recent years that the endurance/perdurance debate is merely verbal: these prima facie distinct theories of objects’ persistence are in fact metaphysically equivalent, they claim. The present paper challenges this view. Three proposed translation schemes (those set forth by Miller 2005; McCall and Lowe 2006; Hirsch 2009) are examined; all are shown to be faul

Predictive markers of abdominal aortic stiffness measured by echo-tracking in subjects with varying insulin sensitivity.

Arterial stiffness is influenced by advancing age and vascular disease and is an independent risk factor for cardiovascular events and death. Using ultrasound measurements, arterial stiffness in a specific arterial segment can be assessed. The aim of this observational study was to explore the prospective and cross-sectional associations between arterial stiffness measured by ultrasound locally in

On a coloured tree with non i.i.d. random labels

We obtain new results for the probabilistic model introduced in Menshikov et al. (2007) and Volkov (2006) which involves a dd-ary regular tree. All vertices are coloured in one of dd distinct colours so that dd children of each vertex all have different colours. Fix d2d2 strictly positive random variables. For any two connected vertices of the tree assign to the edge between them a label which has

Molecular and cytological analysis of the expression of Streptomyces sporulation regulatory gene whiH.

The whiH gene is required for the orderly sporulation septation that divides aerial hyphae into spores in Streptomyces coelicolor. Here, we use a whiHp-mCherry transcriptional reporter construct to show that whiHp is active specifically in aerial hyphae, fluorescence being dependent on sporulation sigma factor WhiG. The results show that the promoter is active before the septation event that separ

Proliferation of amyloid-beta 42 aggregates occurs through a secondary nucleation mechanism

The generation of toxic oligomers during the aggregation of the amyloid-beta (A beta) peptide A beta 42 into amyloid fibrils and plaques has emerged as a central feature of the onset and progression of Alzheimer's disease, but the molecular pathways that control pathological aggregation have proved challenging to identify. Here, we use a combination of kinetic studies, selective radiolabeling expe

Animal Models of Parkinson's Disease: Limits and Relevance to Neuroprotection Studies

Over the last two decades, significant strides has been made toward acquiring a better knowledge of both the etiology and pathogenesis of Parkinson's disease (PD). Experimental models are of paramount importance to obtain greater insights into the pathogenesis of the disease. Thus far, neurotoxin-based animal models have been the most popular tools employed to produce selective neuronal death in b

Commutativity and ideals in category crossed products

In order to simultaneously generalize matrix rings and group graded crossed products, we introduce category crossed products. For such algebras we describe the centre and the commutant of the coefficient ring. We also investigate the connection between on the one hand maximal commutativity of the coefficient ring and on the other hand nonemptiness of intersections of the coefficient ring by nonzer