Polymorphic microsatellite loci for primitively eusocial wasp Ropalidia marginata

We report here development and characterization of 48 novel microsatellite markers for Ropalidia marginata, a tropical, primitively eusocial polistine wasp from peninsular India. Thirty-two microsatellites showed polymorphism in a wild population of R. marginata (N = 38) collected from Bangalore, India. These markers will facilitate answering some interesting questions in ecology and evolutionary biology of this wasp, such as population structure, serial polygyny, intra-colony genetic relatedness and the pattern of queen succession.

Towards a temperature-guided molecular switch: an unusual reversible low-temperature polymorphic phase transition in a conformational locked environment

A conformationally locked tetraacetate undergoes, quite akin to a temperature-guided molecular switch, a reversible thermal switching between two polymorphic modifications; the room-temperature alpha-form converted at -4 degrees C to a low-temperature denser beta-form, which displayed an unusual kinetic stability till 67 degrees C and transformed back to the alpha-form beyond this temperature.

Redefine: Runtime Reconfigurable Polymorphic ASIC

Emerging embedded applications are based on evolving standards (e.g., MPEG2/4, H.264/265, IEEE802.11a/b/g/n). Since most of these applications run on handheld devices, there is an increasing need for a single chip solution that can dynamically interoperate between different standards and their derivatives. In order to achieve high resource utilization and low power dissipation, we propose REDEFINE, a polymorphic ASIC in which specialized hardware units are replaced with basic hardware units that can create the same functionality by runtime re-composition. It is a ``future-proof'' custom hardware solution for multiple applications and their derivatives in a domain. In this article, we describe a compiler framework and supporting hardware comprising compute, storage, and communication resources. Applications described in high-level language (e.g., C) are compiled into application substructures. For each application substructure, a set of compute elements on the hardware are interconnected during runtime to form a pattern that closely matches the communication pattern of that particular application. The advantage is that the bounded CEs are neither processor cores nor logic elements as in FPGAs. Hence, REDEFINE offers the power and performance advantage of an ASIC and the hardware reconfigurability and programmability of that of an FPGA/instruction set processor. In addition, the hardware supports custom instruction pipelining. Existing instruction-set extensible processors determine a sequence of instructions that repeatedly occur within the application to create custom instructions at design time to speed up the execution of this sequence. We extend this scheme further, where a kernel is compiled into custom instructions that bear strong producer-consumer relationship (and not limited to frequently occurring sequences of instructions). Custom instructions, realized as hardware compositions effected at runtime, allow several instances of the same to be active in parallel. A key distinguishing factor in majority of the emerging embedded applications is stream processing. To reduce the overheads of data transfer between custom instructions, direct communication paths are employed among custom instructions. In this article, we present the overview of the hardware-aware compiler framework, which determines the NoC-aware schedule of transports of the data exchanged between the custom instructions on the interconnect. The results for the FFT kernel indicate a 25% reduction in the number of loads/stores, and throughput improves by log(n) for n-point FFT when compared to sequential implementation. Overall, REDEFINE offers flexibility and a runtime reconfigurability at the expense of 1.16x in power and 8x in area when compared to an ASIC. REDEFINE implementation consumes 0.1x the power of an FPGA implementation. In addition, the configuration overhead of the FPGA implementation is 1,000x more than that of REDEFINE.

An Input Triggered Polymorphic ASIC for H.264 Decoding

This paper reports the design of an input-triggered polymorphic ASIC for H.264 baseline decoder. Hardware polymorphism is achieved by selectively reusing hardware resources at system and module level. Complete design is done using ESL design tools following a methodology that maintains consistency in testing and verification throughout the design flow. The proposed design can support frame sizes from QCIF to 1080p.

Architecture of a polymorphic ASIC for interoperability across multi-mode H.264 decoders

Run-time interoperability between different applications based on H.264/AVC is an emerging need in networked infotainment, where media delivery must match the desired resolution and quality of the end terminals. In this paper, we describe the architecture and design of a polymorphic ASIC to support this. The H.264 decoding flow is partitioned into modules, such that the polymorphic ASIC meets the design goals of low-power, low-area, high flexibility, high throughput and fast interoperability between different profiles and levels of H.264. We demonstrate the idea with a multi-mode decoder that can decode baseline, main and high profile H.264 streams and can interoperate at run.time across these profiles. The decoder is capable of processing frame sizes of up to 1024 times 768 at 30 fps. The design synthesized with UMC 0.13 mum technology, occupies 250 k gates and runs at 100 MHz.

Crystal Structures of a New Polymorphic Form of Gabapentin Monohydrate and the E and Z Isomers of 4-Tertiarybutylgabapentin

Gabapentin, a widely used antiepileptic drug, crystallizes in multiple polymorphic forms. A new crystal form of gabapentin monohydrate in the space group Pbca is reported and the packing arrangement compared with that of a previously reported polymorph in the space group P2(1)/c [Ibers, J.A. (2001) Acta Crystallogr; C57:641]. Gabapentin polymorphs can also occur from a selection of one of the two distinct chair forms of the 1,1-disubstituted cyclohexane. Crystal structures of the E and Z isomers of 4-tert-butylgabapentin provide models for analyzing anticipated packing modes in the conformational isomers of gabapentin. The E isomer crystallized in the space group Pca2(1), while the Z isomer crystallized in the space group P2(1)/c. The crystal structure of E-4-tert-butylgabapentin provides the only example of a structure in a non-centrosymmetric space group. Crystal structures of the hydrochloride and hydrobromide salts of 4-tert-butyl derivatives are reported. The results suggest that for gabapentin, a large 'polymorph-space' may be anticipated, in view of the multiple conformational states that are accessible to the molecule.

RECONNECT: A NoC for polymorphic ASICs using a low overhead single cycle router

A polymorphic ASIC is a runtime reconfigurable hardware substrate comprising compute and communication elements. It is a ldquofuture proofrdquo custom hardware solution for multiple applications and their derivatives in a domain. Interoperability between application derivatives at runtime is achieved through hardware reconfiguration. In this paper we present the design of a single cycle Network on Chip (NoC) router that is responsible for effecting runtime reconfiguration of the hardware substrate. The router design is optimized to avoid FIFO buffers at the input port and loop back at output crossbar. It provides virtual channels to emulate a non-blocking network and supports a simple X-Y relative addressing scheme to limit the control overhead to 9 bits per packet. The 8times8 honeycomb NoC (RECONNECT) implemented in 130 nm UMC CMOS standard cell library operates at 500 MHz and has a bisection bandwidth of 28.5 GBps. The network is characterized for random, self-similar and application specific traffic patterns that model the execution of multimedia and DSP kernels with varying network loads and virtual channels. Our implementation with 4 virtual channels has an average network latency of 24 clock cycles and throughput of 62.5% of the network capacity for random traffic. For application specific traffic the latency is 6 clock cycles and throughput is 87% of the network capacity.

Experimental and Theoretical Charge Density Analysis of Polymorphic Structures: The Case of Coumarin 314 Dye

Experimental charge density distributions in two known conformational polymorphs (orange and yellow) of coumarin 314 dye are analyzed based on multipole modeling of X-ray diffraction data collected at 100 K. The experimental results are compared with the charge densities derived from multipole modeling of theoretical structure factors obtained from periodic quantum calculation with density functional theory (DFT) method and B3LYP/6-31G(d,p) level of theory. The presence of disorder at the carbonyl oxygen atom of ethoxycarbonyl group in the yellow form, which was not identified earlier, is addressed here. The investigationof intermolecular interactions, based on Hirshfeld surface analysis and topological properties via quantum theory of atoms in molecule and total electrostatic interaction energies, revealed significant differences between the polymorphs. The differences of electrostatic nature in these two polymorphic forms were unveiled via construction of three-dimensional deformation electrostatic potential maps plotted over the molecular surfaces. The lattice energies evaluated from ab initio calculations on the two polymorphic forms indicate that the yellow form is likely to be the most favorable thermodynamically. The dipole moments derived from experimental and theoretical charge densities and also from Lorentz tensor approach are compared with the single-molecule dipole moments. In each case, the differences of dipole moments between the polymorphs are identified.

A Flexible Crypto-system Based upon the REDEFINE Polymorphic ASIC Architecture

The highest levels of security can be achieved through the use of more than one type of cryptographic algorithm for each security function. In this paper, the REDEFINE polymorphic architecture is presented as an architecture framework that can optimally support a varied set of crypto algorithms without losing high performance. The presented solution is capable of accelerating the advanced encryption standard (AES) and elliptic curve cryptography (ECC) cryptographic protocols, while still supporting different flavors of these algorithms as well as different underlying finite field sizes. The compelling feature of this cryptosystem is the ability to provide acceleration support for new field sizes as well as new (possibly proprietary) cryptographic algorithms decided upon after the cryptosystem is deployed.

Polymorphic Anhydrous Cocrystals of Gallic Acid and Acetamide from Methanol: Pointers toward a Stable Cocrystal Form

Polymorphic anhydrous cocrystals generated from a methanolic solution of gallic acid monohydrate and acetamide are shown to convert to the stable form II on complete drying, and the pathway to the stable form is explained on the basis of the variability in the hydrogen bonding patterns followed by theoretical calculations.

Polymorphism and tautomeric preference in fenobam and the utility of NLO response to detect polymorphic impurities

Crystal structures of polymorphs and solvatomorphs of the potential anxiolytic drug fenobam exhibit an exclusive preference for one of the two possible tautomeric structures. A novel methodology based on nonlinear optical response has been successfully employed to detect the presence of a polymorphic impurity in a mixture of polymorphs.

Polymorphic phase boundaries and enhanced piezoelectric response in extended composition range in the lead free ferroelectric BaTi1-xZrxO3

Neutron powder diffraction study of Ba(Ti1-xZrx)O-3 at close composition intervals has revealed coexistence of ferroelectric phases: orthorhombic (Amm2) + tetragonal (P4mm) for 0.02 <= x <= 0.05 and rhombohedral (R3m) + orthorhombic (Amm2) for 0.07 <= x < 0.09. These compositions exhibit relatively enhanced piezoelectric properties as compared to their single phase counterparts outside this composition region, confirming the polymorphic phase boundary nature of the phase coexistence regions. (C) 2013 AIP Publishing LLC.

Shear induced crystallization in different polymorphic forms of PVDF induced by surface functionalized MWNTs in PVDF/PMMA blends

Shear induced crystallization in PVDF/PMMA blends, especially at higher fractions of PMMA, can be quite interesting in understanding the structure-property correlation and processing of these blends. In a recent submission (Phys. Chem. Chem. Phys., 2014, 16, 2693-2704), we clearly demonstrated, using dielectric spectroscopy, that the origin of segmental relaxations concerning the crystalline segments of PVDF in PVDF/PMMA blends in the presence of MWNTs (multiwalled nanotubes) was strongly contingent on the size of the crystallite. We now understand that the fraction of PMMA in the blends governs the origin of polymorphism in PVDF. This motivated us to systematically study the effect of shear on the crystallization behavior of PVDF especially in blends with different polymorphic forms of PVDF. Two model blends were selected; one with a mixture of alpha and beta crystals and the other predominantly rich in alpha crystals. Initially, physical ageing, at different oscillation frequencies (1 rad s(-1) and 0.1 rad s(-1)), was monitored by melt rheology and subsequently, the effect of steady shear was probed in situ without changing the history of the samples. Intriguingly, the rate of crystallization was observed to be significantly higher for higher oscillation frequencies, which essentially suggest that shear has induced crystallization in the blends. More interestingly, the effect of steady shear was more pronounced in the blends rich in alpha crystals (bigger crystallites as observed from SAXS) and at lower oscillation frequencies.

Polymorphic phase transition among the titania crystal structures using a solution-based approach: from precursor chemistry to nucleation process

Nanocrystalline titania are a robust candidate for various functional applications owing to its non-toxicity, cheap availability, ease of preparation and exceptional photochemical as well as thermal stability. The uniqueness in each lattice structure of titania leads to multifaceted physico-chemical and opto-electronic properties, which yield different functionalities and thus influence their performances in various green energy applications. The high temperature treatment for crystallizing titania triggers inevitable particle growth and the destruction of delicate nanostructural features. Thus, the preparation of crystalline titania with tunable phase/particle size/morphology at low to moderate temperatures using a solution-based approach has paved the way for further exciting areas of research. In this focused review, titania synthesis from hydrothermal/solvothermal method, conventional sol-gel method and sol-gel-assisted method via ultrasonication, photoillumination and ILs, thermolysis and microemulsion routes are discussed. These wet chemical methods have broader visibility, since multiple reaction parameters, such as precursor chemistry, surfactants, chelating agents, solvents, mineralizer, pH of the solution, aging time, reaction temperature/time, inorganic electrolytes, can be easily manipulated to tune the final physical structure. This review sheds light on the stabilization/phase transformation pathways of titania polymorphs like anatase, rutile, brookite and TiO2(B) under a variety of reaction conditions. The driving force for crystallization arising from complex species in solution coupled with pH of the solution and ion species facilitating the orientation of octahedral resulting in a crystalline phase are reviewed in detail. In addition to titanium halide/alkoxide, the nucleation of titania from other precursors like peroxo and layered titanates are also discussed. The nonaqueous route and ball milling-induced titania transformation is briefly outlined; moreover, the lacunae in understanding the concepts and future prospects in this exciting field are suggested.

Smaller is Plastic: Polymorphic Structures and Mechanism of Deformation in Nanoscale hcp Metals

Using first-principles calculations, we establish the existence of highly-stable polymorphs of hcp metals (Ti, Mg, Be, La and Y) with nanoscale structural periodicity. They arise from heterogeneous deformation of the hcp structure occurring in response to large shear stresses localized at the basal planes separated by a few nanometers. Through Landau theoretical analysis, we show that their stability derives from nonlinear coupling between strains at different length scales. Such multiscale hyperelasticity and long-period structures constitute a new mechanism of size-dependent plasticity and its enhancement in nanoscale hcp metals.