8,045 research outputs found
Branding the nation: Towards a better understanding
This paper aims to clarify some misunderstanding about nation branding. It examines the origins and interpretations of the concept, and draws a comparison between nation branding and commercial branding. A new definition is offered that emphasises the need to shift from âbrandingâ the nation to nation image management
Foot Bone in Vivo: Its Center of Mass and Centroid of Shape
This paper studies foot bone geometrical shape and its mass distribution and
establishes an assessment method of bone strength. Using spiral CT scanning,
with an accuracy of sub-millimeter, we analyze the data of 384 pieces of foot
bones in vivo and investigate the relationship between the bone's external
shape and internal structure. This analysis is explored on the bases of the
bone's center of mass and its centroid of shape. We observe the phenomenon of
superposition of center of mass and centroid of shape fairly precisely,
indicating a possible appearance of biomechanical organism. We investigate two
aspects of the geometrical shape, (i) distance between compact bone's centroid
of shape and that of the bone and (ii) the mean radius of the same density bone
issue relative to the bone's centroid of shape. These quantities are used to
interpret the influence of different physical exercises imposed on bone
strength, thereby contributing to an alternate assessment technique to bone
strength.Comment: 9 pages, 4 figure
Transgene-specific and event-specific molecular markers for characterization of transgenic papaya lines resistant to Papaya ringspot virus
Arcula: A Secure Hierarchical Deterministic Wallet for Multi-asset Blockchains
This work presents Arcula, a new design for hierarchical deterministic
wallets that brings identity-based addresses to the blockchain. Arcula is built
on top of provably secure cryptographic primitives. It generates all its
cryptographic secrets from a user-provided seed and enables the derivation of
new public keys based on the identities of users, without requiring any secret
information. Unlike other wallets, it achieves all these properties while being
secure against privilege escalation. We formalize the security model of
hierarchical deterministic wallets and prove that an attacker compromising an
arbitrary number of users within an Arcula wallet cannot escalate his
privileges and compromise users higher in the access hierarchy. Our design
works out-of-the-box with any blockchain that enables the verification of
signatures on arbitrary messages. We evaluate its usage in a real-world
scenario on the Bitcoin Cash network
Listen to genes : dealing with microarray data in the frequency domain
Background: We present a novel and systematic approach to analyze temporal microarray data. The approach includes
normalization, clustering and network analysis of genes.
Methodology: Genes are normalized using an error model based uniform normalization method aimed at identifying and
estimating the sources of variations. The model minimizes the correlation among error terms across replicates. The
normalized gene expressions are then clustered in terms of their power spectrum density. The method of complex Granger
causality is introduced to reveal interactions between sets of genes. Complex Granger causality along with partial Granger
causality is applied in both time and frequency domains to selected as well as all the genes to reveal the interesting
networks of interactions. The approach is successfully applied to Arabidopsis leaf microarray data generated from 31,000
genes observed over 22 time points over 22 days. Three circuits: a circadian gene circuit, an ethylene circuit and a new
global circuit showing a hierarchical structure to determine the initiators of leaf senescence are analyzed in detail.
Conclusions: We use a totally data-driven approach to form biological hypothesis. Clustering using the power-spectrum
analysis helps us identify genes of potential interest. Their dynamics can be captured accurately in the time and frequency
domain using the methods of complex and partial Granger causality. With the rise in availability of temporal microarray
data, such methods can be useful tools in uncovering the hidden biological interactions. We show our method in a step by
step manner with help of toy models as well as a real biological dataset. We also analyse three distinct gene circuits of
potential interest to Arabidopsis researchers
Stealth Supersymmetry
We present a broad class of supersymmetric models that preserve R-parity but
lack missing energy signatures. These models have new light particles with
weak-scale supersymmetric masses that feel SUSY breaking only through couplings
to the MSSM. This small SUSY breaking leads to nearly degenerate fermion/boson
pairs, with small mass splittings and hence small phase space for decays
carrying away invisible energy. The simplest scenario has low-scale SUSY
breaking, with missing energy only from soft gravitinos. This scenario is
natural, lacks artificial tunings to produce a squeezed spectrum, and is
consistent with gauge coupling unification. The resulting collider signals will
be jet-rich events containing false resonances that could resemble signatures
of R-parity violation. We discuss several concrete examples of the general
idea, and emphasize gamma + jet + jet resonances, displaced vertices, and very
large numbers of b-jets as three possible discovery modes.Comment: 12 pages, 4 figure
Obesity is associated with depot-specific alterations in adipocyte DNA methylation and gene expression
The interaction between a sexually transferred steroid hormone and a female protein regulates oogenesis in the malaria mosquito anopheles gambiae
Molecular interactions between male and female factors during mating profoundly affect the reproductive behavior and physiology of female insects. In natural populations of the malaria mosquito Anopheles gambiae, blood-fed females direct nutritional resources towards oogenesis only when inseminated. Here we show that the mating-dependent pathway of egg development in these mosquitoes is regulated by the interaction between the steroid hormone 20-hydroxy-ecdysone (20E) transferred by males during copulation and a female Mating-Induced Stimulator of Oogenesis (MISO) protein. RNAi silencing of MISO abolishes the increase in oogenesis caused by mating in blood-fed females, causes a delay in oocyte development, and impairs the function of male-transferred 20E. Co-immunoprecipitation experiments show that MISO and 20E interact in the female reproductive tract. Moreover MISO expression after mating is induced by 20E via the Ecdysone Receptor, demonstrating a close cooperation between the two factors. Male-transferred 20E therefore acts as a mating signal that females translate into an increased investment in egg development via a MISO-dependent pathway. The identification of this maleâfemale reproductive interaction offers novel opportunities for the control of mosquito populations that transmit malaria
Short acquisition time PET quantification using MRI-based pharmacokinetic parameter synthesis
Positron Emission Tomography (PET) with pharmacokinetic (PK) modelling is a quantitative molecular imaging technique, however the long data acquisition time is prohibitive in clinical practice. An approach has been proposed to incorporate blood flow information from Arterial Spin Labelling (ASL) Magnetic Resonance Imaging (MRI) into PET PK modelling to reduce the acquisition time. This requires the conversion of cerebral blood flow (CBF) maps, measured by ASL, into the relative tracer delivery parameter (R 1 ) used in the PET PK model. This was performed regionally using linear regression between population R 1 and ASL values. In this paper we propose a novel technique to synthesise R 1 maps from ASL data using a database with both R 1 and CBF maps. The local similarity between the candidate ASL image and those in the database is used to weight the propagation of R 1 values to obtain the optimal patient specific R 1 map. Structural MRI data is also included to provide information within common regions of artefact in ASL data. This methodology is compared to the linear regression technique using leave one out analysis on 32 subjects. The proposed method significantly improves regional R 1 estimation (p < 0.001), reducing the error in the pharmacokinetic modelling. Furthermore, it allows this technique to be extended to a voxel level, increasing the clinical utility of the images
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