On the General Ericksen-Leslie System: Parodi's Relation, Well-posedness and Stability

In this paper we investigate the role of Parodi's relation in the well-posedness and stability of the general Ericksen-Leslie system modeling nematic liquid crystal flows. First, we give a formal physical derivation of the Ericksen-Leslie system through an appropriate energy variational approach under Parodi's relation, in which we can distinguish the conservative/dissipative parts of the induced elastic stress. Next, we prove global well-posedness and long-time behavior of the Ericksen-Leslie system under the assumption that the viscosity $\mu_4$ is sufficiently large. Finally, under Parodi's relation, we show the global well-posedness and Lyapunov stability for the Ericksen-Leslie system near local energy minimizers. The connection between Parodi's relation and linear stability of the Ericksen-Leslie system is also discussed

Sharp Global Bounds for the Hessian on Pseudo-Hermitian Manifolds

We find sharp bounds for the norm inequality on a Pseudo-hermitian manifold, where the L^2 norm of all second derivatives of the function involving horizontal derivatives is controlled by the L^2 norm of the sub-Laplacian. Perturbation allows us to get a-priori bounds for solutions to sub-elliptic PDE in non-divergence form with bounded measurable coefficients. The method of proof is through a Bochner technique. The Heisenberg group is seen to be en extremal manifold for our inequality in the class of manifolds whose Ricci curvature is non-negative.Comment: 13 page

A Sulfhydryl-Reactive Ruthenium (II) Complex and Its Conjugation to Protein G as a Universal Reagent for Fluorescent Immunoassays

To develop a fluorescent ruthenium complex for biosensing, we synthesized a novel sulfhydryl-reactive compound, 4-bromophenanthroline bis-2,2′-dipyridine Ruthenium bis (hexafluorophosphate). The synthesized Ru(II) complex was crosslinked with thiol-modified protein G to form a universal reagent for fluorescent immunoassays. The resulting Ru(II)-protein G conjugates were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The emission peak wavelength of the Ru(II)-protein G conjugate was 602 nm at the excitation of 452 nm which is similar to the spectra of the Ru(II) complex, indicating that Ru(II)-protein G conjugates still remain the same fluorescence after conjugation. To test the usefulness of the conjugate for biosensing, immunoglobulin G (IgG) binding assay was conducted. The result showed that Ru(II)-protein G conjugates were capable of binding IgG and the more cross-linkers to modify protein G, the higher conjugation efficiency. To demonstrate the feasibility of Ru(II)-protein G conjugates for fluorescent immunoassays, the detection of recombinant histidine-tagged protein using the conjugates and anti-histidine antibody was developed. The results showed that the histidine-tagged protein was successfully detected with dose-response, indicating that Ru(II)-protein G conjugate is a useful universal fluorescent reagent for quantitative immunoassays

Influence of irrigant needle depth in removing bioluminescent bacteria inoculated into instrumented root canals using real-time imaging in vitro

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73506/1/j.1365-2591.2004.00906.x.pd

Decision making and experiences of young adults undergoing presymptomatic genetic testing for familial cancer: A longitudinal grounded theory study

Enabling informed choice is an essential component of care when offering young adults presymptomatic testing for a genetic condition. A systematic review on this topic revealed that many young adults grew up with little information regarding their genetic risk and that parents had applied pressure to them during the testing decision-making process. However, none of the studies retrieved were conducted in South European countries. To address this gap, we undertook a qualitative study based on grounded theory to explore the psychosocial implications of presymptomatic testing for hereditary cancer in Italian young adults aged 18-30 years. Interviews were conducted on three occasions: 1 month before counselling, and 2 weeks and 6 months after results. Data were coded and grouped under themes. A total of 42 interviews were conducted. Four themes emerged: knowledge, genetic counselling process, decision making and dealing with test results. Although participants grew up with little or no information about their genetic risk, none expressed regret at having the test at a young age. Pre-test counselling was appreciated as a source of information, rather than support for decision making. Decisions were often made autonomously and sometimes conflicted with parents' wishes. Participants reported no changes in health behaviours after testing. This evidence highlights the need for a comprehensive, longitudinal counselling process with appropriate timing and setting, which supports 'parent-to-offspring' risk communication first and decision making by young adults about presymptomatic testing and risk management afterwards. In conclusion, it is clear that counselling approaches for presymptomatic testing may require modification both for young adults and their parents. © 2017 European Society of Human Genetics

Origin of Cosmic Magnetic Fields

We propose that the overlapping shock fronts from young supernova remnants produce a locally unsteady, but globally steady large scale spiral shock front in spiral galaxies, where star formation and therefore massive star explosions correlate geometrically with spiral structure. This global shock front with its steep gradients in temperature, pressure and associated electric fields will produce drifts, which in turn give rise to a strong sheet-like electric current, we propose. This sheet current then produces a large scale magnetic field, which is regular, and connected to the overall spiral structure. This rejuvenates the overall magnetic field continuously, and also allows to understand that there is a regular field at all in disk galaxies. This proposal connects the existence of magnetic fields to accretion in disks. We not yet address all the symmetries of the magnetic field here; the picture proposed here is not complete. X-ray observations may be able to test it already.Comment: 18 pages, no figures; to be published in Proc. Palermo Meeting Sept. 2002, Eds. N. G. Sanchez et al., The Early Universe and the Cosmic Microwave Background: Theory and Observation

A class of extremising sphere-valued maps with inherent maximal tori symmetries in SO(n)

In this paper we consider an energy functional depending on the norm of the gradient and seek to extremise it over an admissible class of Sobolev maps defined on an annulus and taking values on the unit sphere whilst satisfying suitable boundary conditions. We establish the existence of an infinite family of solutions with certain symmetries to the associated nonlinear Euler-Lagrange system in even dimensions and discuss the stability of such extremisers by way of examining the positivity of the second variation of the energy at these solutions

DNA topoisomerases participate in fragility of the oncogene RET

Fragile site breakage was previously shown to result in rearrangement of the RET oncogene, resembling the rearrangements found in thyroid cancer. Common fragile sites are specific regions of the genome with a high susceptibility to DNA breakage under conditions that partially inhibit DNA replication, and often coincide with genes deleted, amplified, or rearranged in cancer. While a substantial amount of work has been performed investigating DNA repair and cell cycle checkpoint proteins vital for maintaining stability at fragile sites, little is known about the initial events leading to DNA breakage at these sites. The purpose of this study was to investigate these initial events through the detection of aphidicolin (APH)-induced DNA breakage within the RET oncogene, in which 144 APHinduced DNA breakpoints were mapped on the nucleotide level in human thyroid cells within intron 11 of RET, the breakpoint cluster region found in patients. These breakpoints were located at or near DNA topoisomerase I and/or II predicted cleavage sites, as well as at DNA secondary structural features recognized and preferentially cleaved by DNA topoisomerases I and II. Co-treatment of thyroid cells with APH and the topoisomerase catalytic inhibitors, betulinic acid and merbarone, significantly decreased APH-induced fragile site breakage within RET intron 11 and within the common fragile site FRA3B. These data demonstrate that DNA topoisomerases I and II are involved in initiating APH-induced common fragile site breakage at RET, and may engage the recognition of DNA secondary structures formed during perturbed DNA replication

Scattering Theory and PT\mathcal{P}\mathcal{T}-Symmetry

We outline a global approach to scattering theory in one dimension that allows for the description of a large class of scattering systems and their $\mathcal{P}$-, $\mathcal{T}$-, and $\mathcal{P}\mathcal{T}$-symmetries. In particular, we review various relevant concepts such as Jost solutions, transfer and scattering matrices, reciprocity principle, unidirectional reflection and invisibility, and spectral singularities. We discuss in some detail the mathematical conditions that imply or forbid reciprocal transmission, reciprocal reflection, and the presence of spectral singularities and their time-reversal. We also derive generalized unitarity relations for time-reversal-invariant and $\mathcal{P}\mathcal{T}$-symmetric scattering systems, and explore the consequences of breaking them. The results reported here apply to the scattering systems defined by a real or complex local potential as well as those determined by energy-dependent potentials, nonlocal potentials, and general point interactions.Comment: Slightly expanded revised version, 38 page

ATP and its N6-substituted analogues: parameterization, molecular dynamics simulation and conformational analysis

In this work we used a combination of classical molecular dynamics and simulated annealing techniques to shed more light on the conformational flexibility of 12 adenosine triphosphate (ATP) analogues in a water environment. We present simulations in AMBER force field for ATP and 12 published analogues [Shah et al. (1997) Proc Natl Acad Sci USA 94: 3565–3570]. The calculations were carried out using the generalized Born (GB) solvation model in the presence of the cation Mg2+. The ion was placed at a close distance (2 Å) from the charged oxygen atoms of the beta and gamma phosphate groups of the −3 negatively charged ATP analogue molecules. Analysis of the results revealed the distribution of inter-proton distances H8–H1′ and H8–H2′ versus the torsion angle ψ (C4–N9-C1′–O4′) for all conformations of ATP analogues. There are two gaps in the distribution of torsion angle ψ values: the first is between −30 and 30 degrees and is described by cis-conformation; and the second is between 90 and 175 degrees, which mostly covers a region of anti conformation. Our results compare favorably with results obtained in experimental assays [Jiang and Mao (2002) Polyhedron 21:435–438]