Anomalous Defects and Their Quantized Transverse Conductivities

Using a description of defects in solids in terms of three-dimensional gravity, we study the propagation of electrons in the background of disclinations and screw dislocations. We study the situations where there are bound states that are effectively localized on the defect and hence can be described in terms of an effective 1+1 dimensional field theory for the low energy excitations. In the case of screw dislocations, we find that these excitations are chiral and can be described by an effective field theory of chiral fermions. Fermions of both chirality occur even for a given direction of the magnetic field. The ``net'' chirality of the system however is not always the same for a given direction of the magnetic field, but changes from one sign of the chirality through zero to the other sign as the Fermi momentum or the magnitude of the magnetic flux is varied. On coupling to an external electromagnetic field, the latter becomes anomalous, and predicts novel conduction properties for these materials.Comment: New material added. ReVTeX , 31 pgs., 4 figs.(uses epsf

Deformable Nanovesicles Synthesized through an Adaptable Microfluidic Platform for Enhanced Localized Transdermal Drug Delivery.

Phospholipid-based deformable nanovesicles (DNVs) that have flexibility in shape offer an adaptable and facile method to encapsulate diverse classes of therapeutics and facilitate localized transdermal delivery while minimizing systemic exposure. Here we report the use of a microfluidic reactor for the synthesis of DNVs and show that alteration of input parameters such as flow speeds as well as molar and flow rate ratios increases entrapment efficiency of drugs and allows fine-tuning of DNV size, elasticity, and surface charge. To determine the ability of DNV-encapsulated drug to be delivered transdermally to a local site, we synthesized, characterized, and tested DNVs carrying the fluorescently labeled hydrophilic bisphosphonate drug AF-647 zoledronate (AF647-Zol). AF647-Zol DNVs were lyophilized, resuspended, and applied topically as a paste to the calvarial skin of mice. High-resolution fluorescent imaging and confocal microscopy revealed significant increase of encapsulated payload delivery to the target tissue-cranial bone-by DNVs as compared to nondeformable nanovesicles (NVs) or aqueous drug solutions. Interestingly, NV delivery was not superior to aqueous drug solution. Our studies show that microfluidic reactor-synthesized DNVs can be produced in good yield, with high encapsulation efficiency, reproducibility, and stability after storage, and represent a useful vehicle for localized transdermal drug delivery

A small molecule ApoE4-targeted therapeutic candidate that normalizes sirtuin 1 levels and improves cognition in an Alzheimer's disease mouse model.

We describe here the results from the testing of a small molecule first-in-class apolipoprotein E4 (ApoE4)-targeted sirtuin1 (SirT1) enhancer, A03, that increases the levels of the neuroprotective enzyme SirT1 while not affecting levels of neurotoxic sirtuin 2 (SirT2) in vitro in ApoE4-transfected cells. A03 was identified by high-throughput screening (HTS) and found to be orally bioavailable and brain penetrant. In vivo, A03 treatment increased SirT1 levels in the hippocampus of 5XFAD-ApoE4 (E4FAD) Alzheimer's disease (AD) model mice and elicited cognitive improvement while inducing no observed toxicity. We were able to resolve the enantiomers of A03 and show using in vitro models that the L-enantiomer was more potent than the corresponding D-enantiomer in increasing SirT1 levels. ApoE4 expression has been shown to decrease the level of the NAD-dependent deacetylase and major longevity determinant SirT1 in brain tissue and serum of AD patients as compared to normal controls. A deficiency in SirT1 level has been recently implicated in increased tau acetylation, a dominant post-translational modification and key pathological event in AD and tauopathies. Therefore, as a novel approach to therapeutic development for AD, we targeted identification of compounds that enhance and normalize brain SirT1 levels

Rhizosphere bacterial diversity and heavy metal accumulation in Nymphaea pubescens in aid of phytoremediation potential

The present work aims to characterize the bacterial diversity of the rhizosphere system of Nymphaea pubescens and the sediment system where it grows naturally. Heavy metal content in the sediment and Nymphea plant from the selected wetland system were also studied. Results of the current study showed that the concentration of copper, zinc and lead in the sediment ranged from 43 to 182 mg/Kg, from 331 to 1382 mg/Kg and from 121 to 1253 mg/Kg, respectively. Cadmium concentration in sediment samples was found to be zero and the order of abundance of heavy metals in the sediment samples was Zn>Pb>Cu>Cd. The abundance patterns of heavy metals in leaf, petiole and root were Cd>Cu>Pb>Zn. Microbial load in rhizosphere of Nymphea pubescens ranged from 93×102 to 69×103 and that of sediment was 62×102 to 125×103. Bacterial load in rhizosphere was higher than that of growing sediment. Four bacterial genera were identified from the rhizosphere of Nymphaea pubescens which include Acinetobacter, Alcaligens, Listeria and Staphylococcus. Acinetobacter, Alcaligens and Listeria are the three bacterial genera isolated from sediment samples. Copper resistance studies of the 14 bacterial isolates from rhizosphere and 7 strains from sediment samples revealed that most of them showed low resistance (<100 μg/ml) and very few isolates showed high resistance of 400-500 μg/ml

Chern-Simons terms in Noncommutative Geometry and its application to Bilayer Quantum Hall Systems

Considering bilayer systems as extensions of the planar ones by an internal space of two discrete points, we use the ideas of Noncommutative Geometry to construct the gauge theories for these systems. After integrating over the discrete space we find an effective $2+1$ action involving an extra complex scalar field, which can be interpreted as arising from the tunneling between the layers. The gauge fields are found in different phases corresponding to the different correlations due to the Coulomb interaction between the layers. In a particular phase, when the radial part of the complex scalar field is a constant, we recover the Wen-Zee model of Bilayer Quantum Hall systems. There are some circumstances, where this radial part may become dynamical and cause dissipation in the oscillating supercurrent between the layers.Comment: 17 pages, more explanations have been added to make our points clearer compared with the previous densed versio

Genus Zero Correlation Functions in c<1 String Theory

We compute N-point correlation functions of pure vertex operator states(DK states) for minimal models coupled to gravity. We obtain agreement with the matrix model results on analytically continuing in the numbers of cosmological constant operators and matter screening operators. We illustrate this for the cases of the $(2k-1,2)$ and $(p+1,p)$ models.Comment: 11 pages, LaTeX, IMSc--92/35. (revised) minor changes plus one reference adde

Chiral Rings and Physical States in c<1 String Theory

We show how the double cohomology of the String and Felder BRST charges naturally leads to the ring structure of $c<1$ strings. The chiral ring is a ring of polynomials in two variables modulo an equivalence relation of the form $x^p \simeq y^{p+1}$ for the (p+1,p) model. We also study the states corresponding to the edges of the conformal grid whose inclusion is crucial for the closure of the ring. We introduce candidate operators that correspond to the observables of the matrix models. Their existence is motivated by the relation of one of the screening operators of the minimal model to the zero momentum dilaton.Comment: 20 pages, harvmac, 4 figures (drawn using LaTeX appended to the end of the file), IMSc--92/3

The Hausdorff Dimension of Surfaces in Two-Dimensional Quantum Gravity Coupled to Ising Minimal Matter

Within the framework of string field theory the intrinsic Hausdorff dimension d_H of the ensemble of surfaces in two-dimensional quantum gravity has recently been claimed to be 2m for the class of unitary minimal models (p = m+1,q = m). This contradicts recent results from numerical simulations, which consistently find d_H approximatly 4 in the cases m = 2, 3, 5 and infinity. The string field calculations rely on identifying the scaling behavior of geodesic distance and area with respect to a common length scale l. This length scale is introduced by formulating the models on a disk with fixed boundary length l. In this paper we study the relationship between the mean area and the boundary length for pure gravity and the Ising model coupled to gravity. We discuss how this relationship is modified by relevant perturbations in the Ising model. We discuss how this leads to a modified value for the Hausdorff dimension.Comment: 12 pages, Latex. Revised to deal only with Ising matter. Clarifying discussion adde