Area Regge Calculus and Discontinuous Metrics

Taking the triangle areas as independent variables in the theory of Regge calculus can lead to ambiguities in the edge lengths, which can be interpreted as discontinuities in the metric. We construct solutions to area Regge calculus using a triangulated lattice and find that on a spacelike hypersurface no such discontinuity can arise. On a null hypersurface however, we can have such a situation and the resulting metric can be interpreted as a so-called refractive wave.Comment: 18 pages, 1 figur

Anomalous Rotational Relaxation: A Fractional Fokker-Planck Equation Approach

In this study we obtained analytically relaxation function in terms of rotational correlation functions based on Brownian motion for complex disordered systems in a stochastic framework. We found out that rotational relaxation function has a fractional form for complex disordered systems, which indicates relaxation has non-exponential character obeys to Kohlrausch-William-Watts law, following the Mittag-Leffler decay.Comment: Revtex4, 9 pages. Paper was revised. References adde

Antihypertensive drug class and dyslipidemia: risk association among Chinese patients with uncomplicated hypertension

Factors associated with dyslipidemia in Chinese patients with uncomplicated hypertension were investigated in 1,139 patients newly prescribed a single antihypertensive drug in the public primary healthcare setting in Hong Kong, where their fasting lipid profiles were measured 4 to 16 weeks after the first prescription. Multivariate logistic regression showed that thiazide users were more likely (OR 3.67, 95% C.I. 1.13, 11.88, p=0.030) to have adverse (> 6.2mmol/l) total cholesterol (TC) compared with drugs acting on the renin angiotensin system (RAS), but the absolute difference in mean TC between thiazide users and all patients was small ( 0.14 mmol/l), while advanced age and male gender were also associated with some aspects of dyslipidemia. Clinicians should be aware of the increased risk of dyslipidemia in these groups, but the mild dyslipidemic profile associated with thiazides should not in itself deter its use as a possible first-line antihypertensive agent among Chinese patients

Amyloid and tau in the brain in sporadic Alzheimer's disease: defining the chicken and the egg

In the October 2013 issue of Acta Neuropathologica there were three very interesting articles on: Amyloid or tau: the chicken or the egg? In the first article, David Mann and John Hardy argued that the deposition of aggregated amyloid β (Aβ) protein in the brain is a primary driving force behind the pathogenesis of Alzheimer’s disease with tau pathology following as a consequential or at least a secondary event. In the communication that followed, Braak and Del Tredici presented the contrary argument with accumulation of tau protein as the primary event in sporadic Alzheimer’s disease. Attems and Jellinger questioned the concept of a chicken and egg and suggested that the majority of cases of age-associated dementia are not caused by one single primary pathological mechanism

Black Holes in Modified Gravity (MOG)

The field equations for Scalar-Tensor-Vector-Gravity (STVG) or modified gravity (MOG) have a static, spherically symmetric black hole solution determined by the mass $M$ with two horizons. The strength of the gravitational constant is $G=G_N(1+\alpha)$ where $\alpha$ is a parameter. A regular singularity-free MOG solution is derived using a nonlinear field dynamics for the repulsive gravitational field component and a reasonable physical energy-momentum tensor. The Kruskal-Szekeres completion of the MOG black hole solution is obtained. The Kerr-MOG black hole solution is determined by the mass $M$, the parameter $\alpha$ and the spin angular momentum $J=Ma$. The equations of motion and the stability condition of a test particle orbiting the MOG black hole are derived, and the radius of the black hole photosphere and the shadows cast by the Schwarzschild-MOG and Kerr-MOG black holes are calculated. A traversable wormhole solution is constructed with a throat stabilized by the repulsive component of the gravitational field.Comment: 14 pages, 3 figures. Upgraded version of paper to match published version in European Physics Journal

Characterizing normal crossing hypersurfaces

The objective of this article is to give an effective algebraic characterization of normal crossing hypersurfaces in complex manifolds. It is shown that a hypersurface has normal crossings if and only if it is a free divisor, has a radical Jacobian ideal and a smooth normalization. Using K. Saito's theory of free divisors, also a characterization in terms of logarithmic differential forms and vector fields is found and and finally another one in terms of the logarithmic residue using recent results of M. Granger and M. Schulze.Comment: v2: typos fixed, final version to appear in Math. Ann.; 24 pages, 2 figure

Formation and transfer of GaAsN nanostructure layers

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98729/1/JVA060601.pd

Cancer cells exploit an orphan RNA to drive metastatic progression.

Here we performed a systematic search to identify breast-cancer-specific small noncoding RNAs, which we have collectively termed orphan noncoding RNAs (oncRNAs). We subsequently discovered that one of these oncRNAs, which originates from the 3' end of TERC, acts as a regulator of gene expression and is a robust promoter of breast cancer metastasis. This oncRNA, which we have named T3p, exerts its prometastatic effects by acting as an inhibitor of RISC complex activity and increasing the expression of the prometastatic genes NUPR1 and PANX2. Furthermore, we have shown that oncRNAs are present in cancer-cell-derived extracellular vesicles, raising the possibility that these circulating oncRNAs may also have a role in non-cell autonomous disease pathogenesis. Additionally, these circulating oncRNAs present a novel avenue for cancer fingerprinting using liquid biopsies