941 resultados para Essential Closure
Resumo:
A new approach for extracting stress intensity factors (SIFs) by the element-free Galerkin (EFG) class of methods through a modified crack closure integral (MCCI) scheme is proposed. Its primary feature is that it allows accurate calculation of mode I and mode II SIFs with a relatively simple and straightforward analysis even when a coarser nodal density is employed. The details of the adoption of the MCCI technique in the EFG method are described. Its performance is demonstrated through a number of case studies including mixed-mode and thermal problems in linear elastic fracture mechanics (LEFM). The results are compared with published theoretical solutions and those based on the displacement method, stress method, crack closure integral in conjunction with local smoothing (CCI–LS) technique, as well as the M-integral method. Its advantages are discussed.
Resumo:
The cell wall peptidoglycan (PG) of Burkholderia cenocepacia, an opportunistic pathogen, has not yet been characterized. However, the B. cenocepacia genome contains homologs of genes encoding PG biosynthetic functions in other bacteria. PG biosynthesis involves the formation of the undecaprenyl-pyrophosphate-linked N-acetyl glucosamine-N-acetyl muramic acid-pentapeptide, known as lipid II, which is built on the cytosolic face of the cell membrane. Lipid II is then translocated across the membrane and its glycopeptide moiety becomes incorporated into the growing cell wall mesh; this translocation step is critical to PG synthesis. We have investigated candidate flippase homologs of the MurJ family in B. cenocepacia. Our results show that BCAL2764, herein referred to as murJBc, is indispensable for viability. Viable B. cenocepacia could only be obtained through a conditional mutagenesis strategy by placing murJBc under the control of a rhamnose-inducible promoter. Under rhamnose depletion, the conditional strain stopped growing and individual cells displayed morphological abnormalities consistent with a defect in PG synthesis. Bacterial cells unable to express MurJBc underwent cell lysis, while partial MurJBc depletion sensitized the mutant to the action of β-lactam antibiotics. Depletion of MurJBc caused accumulation of PG precursors consistent with the notion that this protein plays a role in lipid II flipping to the periplasmic compartment. Reciprocal complementation experiments of conditional murJ mutants in B. cenocepacia and Escherichia coli with plasmids expressing MurJ from each strain indicated that MurJBc and MurJEc are functional homologs. Together, our results are consistent with the notion that MurJBc is a PG lipid II flippase in B. cenocepacia.
Resumo:
YKL-40 regulates vascular endothelial growth factors and induces tumor proliferation. We investigated YKL-40 before and after treatment with vorinostat in 31 polycythemia vera (PV) and 16 essential thrombocythemia (ET) patients. Baseline PV patient levels were 2 times higher than in healthy controls (P < 0.0001) and 1.7 times higher than in ET (P = 0.02). A significant correlation between YKL-40 at baseline and neutrophils, CRP, LDH, JAK2V617F and platelets in PV patients was observed, as well as a significantly greater reduction of YKL-40 levels in PV patients responding to therapy. YKL-40 might be a novel marker of disease burden and progression in myeloproliferative neoplasms.
Resumo:
Using piezoresponse force microscopy, we have observed the progressive development of ferroelectric flux-closure domain structures and Landau−Kittel-type domain patterns, in 300 nm thick single-crystal BaTiO3 platelets. As the microstructural development proceeds, the rate of change of the domain configuration is seen to decrease exponentially. Nevertheless, domain wall velocities throughout are commensurate with creep processes in oxide ferroelectrics. Progressive screening of macroscopic destabilizing fields, primarily the surface-related depolarizing field, successfully describes the main features of the observed kinetics. Changes in the separation of domain-wall vertex junctions prompt a consideration that vertex−vertex interactions could be influencing the measured kinetics. However, the expected dynamic signatures associated with direct vertex−vertex interactions are not resolved. If present, our measurements confine the length scale for interaction between vertices to the order of a few hundred nanometers.
Resumo:
The German Federal Constitutional Court (FCC) ruling of 14 January 2014 deserves a thorough evaluation on several accounts: It is the first ever reference by the FCC to the Court of Justice of the European Union (CJEU), it represents a continuation of FCC case law aimed at restricting the impact of European Union law as interpreted by the Court of Justices of the European Union (CJEU) on German law as well as questioning Germany’s participation in an ever closer European Union, and it has the potential to dictate the future course of the EU’s Economic and Monetary Union (EMU).
This case note discusses three aspects of this decision. First, it considers the aims of challenging the youngest measures to contain the euro currency crisis before the FCC, focusing on the question in how far the claims are based on national closure as opposed to an ever closer union of the peoples of Europe. Secondly it analyzes in how far the aims the claims pursue are reflected in the FCC’s response. Thirdly, it considers the substantive relevance of this reference, highlighting the surprisingly vague consequences the FCC envisages should the CJEU not re-interpret the OMT decision as the FCC suggests, and illuminating the strategic aims of the reference without deference. In conclusion, it sketches the remaining scope for the EU to engage in or at least facilitate transnational solidarity.
Resumo:
The role of Traditional Birth Attendants in Malawi was vital within a country where maternity services were stretched to their limits
Resumo:
The study assessed the effect of heating vermiculites on extractability of phosphorus, iron, zinc and manganese with respect to their potential agricultural use. Of these elements, phosphorus was from apatite and monazite that occur as accessory minerals in vermiculites. Vermiculites were heated at 15-800 degrees C and digested by acetic acid for extracting phosphorus and diethylene triamine pentaacetic acid (DTPA) for extracting zinc, iron and manganese. Phosphorus in the extract was analysed by a flow injection method while zinc, iron and manganese were measured by atomic absorption spectrometry. The results showed that heating vermiculites to 400 C enhanced extractability of phosphorus from apatite and monazite to a level of 335 mg kg(-1). Further heating to 800 degrees C reduced extractable phosphorus to less than 75 mg kg(-1). Maximum extractable zinc, iron and manganese found were 2.7, 19.1 and 22.9 mg kg(-1), respectively, values that are beneficial and tolerable by most plants. Thus, it was concluded that heating vermiculites to