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Slow-release fluoride devices: a literature review
Pessan, Juliano Pelim;Al-Ibrahim, Nahla Saleh;Buzalaf, Marília Afonso Rabelo;Toumba, Kyriacos Jack;
Journal of Applied Oral Science , 2008, DOI: 10.1590/S1678-77572008000400003
Abstract: although the prevalence of caries has decreased dramatically over the past decades, it has become a polarised disease, with most of subjects presenting low caries levels and few individuals accounting for most of the caries affected surfaces. thus it become evident for the need of clinical approaches directed at these high-risk patients, in order to overcome problems related to compliance and low attendance at dental care centres. slow-release fluoride devices were developed based on the inverse relationship existing between intra-oral fluoride levels and dental caries experience. the two main types of slow-release devices - copolymer membrane type and glass bead - are addressed in the present review. a substantial number of studies have demonstrated that these devices are effective in raising intra-oral f concentrations at levels able to reduce enamel solubility, resulting in a caries-protective effect. studies in animals and humans demonstrated that the use of these devices was able to also protect the occlusal surfaces, not normally protected by conventional fluoride regimens. however, retention rates have been shown to be the main problem related to these devices and still requires further improvements. although the results of these studies are very promising, further randomised clinical trials are needed in order to validate the use of these devices in clinical practice. the concept of continuously providing low levels of intra-oral fluoride has great potential for caries prevention in high caries-risk groups.
Research at the University of Kent and subsequent research activities
Kyriacos Kalli
Photonic Sensors , 2011, DOI: 10.1007/s13320-011-0039-y
Abstract: The author’s research activities undertaken at the Applied Optics Group, the University of Kent at Canterbury are reviewed, during his time there from 1988–1992 and 1994–1996, followed by a summary of recent research. The areas of interest are high finesse ring resonators, tunable optical filters, novel optical fiber grating sensors in glass and polymer, femtosecond laser inscription and micromachining, environmental pollution monitoring, hydrogen activated Pd films on silicon and impurity measurement on silicon wafers.
On Asymptotic Properties of AIC Variants with Applications  [PDF]
Alex Karagrigoriou, Kyriacos Mattheou, Ilia Vonta
Open Journal of Statistics (OJS) , 2011, DOI: 10.4236/ojs.2011.12012
Abstract: In statistical modeling, the investigator is frequently confronted with the problem of selecting an appropriate model from a general class of candidate models. In recent years, various model selection procedures that can be used for the selection of the best possible model have been proposed. The AIC criterion [1] is considered the most popular tool for model selection although many competitors have been introduced over the years. One of the main drawbacks of AIC is its tendency to favor high dimensional models namely to overestimate the true model. A second issue that needs the attention of the investigator is the presence of outlying observations in the data set the inclusion of which in the statistical analysis may lead to erroneous results. In this work we propose AIC variants to handle the above weaknesses. Furthermore the asymptotic properties of the proposed criteria are investigated and a number of applications are discussed.
Deterministic and stochastic population-level simulations of an artificial lac operon genetic network
Michail Stamatakis, Kyriacos Zygourakis
BMC Bioinformatics , 2011, DOI: 10.1186/1471-2105-12-301
Abstract: This work focuses on the dynamics of cell populations by incorporating the above kinetic scheme into two Monte Carlo (MC) simulation frameworks. The first MC framework assumes stochastic reaction occurrence, accounts for stochastic DNA duplication, division and partitioning and tracks all daughter cells to obtain the statistics of the entire cell population. In order to better understand how stochastic effects shape cell population distributions, we develop a second framework that assumes deterministic reaction dynamics. By comparing the predictions of the two frameworks, we conclude that stochasticity can create or destroy bimodality, and may enhance phenotypic heterogeneity.Our results show how various sources of stochasticity act in synergy with the positive feedback architecture, thereby shaping the behavior at the cell population level. Further, the insights obtained from the present study allow us to construct simpler and less computationally intensive models that can closely approximate the dynamics of heterogeneous cell populations.Since the introduction of the operon concept by Jacob et al. [1], the lac operon genetic switch has been considered as a paradigm for genetic regulation. Several experimental studies of this system over the past several decades have elucidated the underlying biomolecular interactions and a plethora of mathematical models have integrated the complex interplays of the key biochemical species in order to predict the behavior of the system [see, for example, [2]].Most of these models, however, pertain to the single cell behavior [see, for example the models reviewed in [3]] with a limited number of studies focusing on cell populations, or taking comparative approaches. For instance, in a mini-review article, Vilar et al. [4] compared different models pertaining to single cells and cell populations, in order to illustrate the performance and limitations of different methodologies. At the single cell level Vilar et al. [4] simulated fou
Detection of Military Underground Structures through the Remote Sensing Investigation of Phenological Cycle of Crops  [PDF]
George Melillos, Kyriacos Themistocleous, George Papadavid, Diofantos G. Hadjimitsis
Advances in Remote Sensing (ARS) , 2018, DOI: 10.4236/ars.2018.73016
Abstract: This paper aims to explore how field spectroscopy is essential for remote sensing studies for the detection and monitoring of various features such military underground structures in Cyprus. A SVC-HR1024 field spectroradiometer was used and in-band reflectances were determined for medium resolution Landsat-7 ETM satellite sensor, in order to study possible differences of the spectral signature of vegetation throughout the phenological cycle of plant growth. In this study, two test areas were identified, analyzed and modelled: 1) Military Structure Area (MSA) where underground structure exists, and 2) Reference Area (RA) where underground military structure does not exist. The Normalized Difference Vegetation Index (NDVI) was applied to Landsat-7 ETM and Sentinel-2 satellite images in order to identify the presence or absence of underground structures in the study area.
BRCA1 and Its Network of Interacting Partners
Charita M. Christou,Kyriacos Kyriacou
Biology , 2013, DOI: 10.3390/biology2010040
Abstract: BRCA1 is a large multi-domain protein with a pivotal role in maintaining genome stability and cell cycle progression. Germline mutations in the BRCA1 gene confer an estimated lifetime risk of 60%–80% for breast cancer and 15%–60% for ovarian cancer. Many of the germline mutations associated with cancer development are concentrated in the amino terminal RING domain and the carboxyl terminal BRCT motifs of BRCA1, which are the most well-characterized regions of the protein. The function of BRCA1 in DNA repair, transcription and cell cycle control through the DNA damage response is orchestrated through its association with an impressive repertoire of protein complexes. The association of BRCA1 with ATM/ATR, CHK2 and Aurora A protein kinases regulates cell cycle progression, whilst its association with RAD51 has a direct impact on the repair of double strand DNA breaks (DSBs) by homologous recombination (HR). BRCA1 interactions with the MRN complex of proteins, with the BRCC complex of proteins that exhibit E3 ligase activity and with the phosphor proteins CtIP, BACH1 (BRIP1) and Abraxas (CCDC98) are also implicated in DNA repair mechanisms and cell cycle checkpoint control. BRCA1 through its association with specific proteins and multi-protein complexes is a sentinel of the normal cell cycle control and DNA repair.
Algebraic Integrability of Lotka-Volterra equations in three dimensions
Kyriacos Constandinides,Pantelis A. Damianou
Mathematics , 2009,
Abstract: We examine the algebraic complete integrability of Lotka-Volterra equations in three dimensions. We restrict our attention to Lotka-Volterra systems defined by a skew symmetric matrix. We obtain a complete classification of such systems. The classification is obtained using Painleve analysis and more specifically by the use of Kowalevski exponents. The imposition of certain integrality conditions on the Kowalevski exponents gives necessary conditions for the algebraic integrability of the corresponding systems. We also show that the conditions are sufficient.
The Tidal Stream Power Curve: A Case Study  [PDF]
Jack Hardisty
Energy and Power Engineering (EPE) , 2012, DOI: 10.4236/epe.2012.43018
Abstract: It is important to understand the relationship between the ambient ebb and flood currents and the electricity generated by tidal stream power generators to minimise investment risk and to optimise power generation for distribution purposes. Such analyses no longer rely on average descriptions of the flow field or on single values for the device efficiency. In the present paper, we demonstrate a new method involving the integration of synthesised long termflow vectors with logistic descriptions of the device power curves. New experiments are then described with the Neptune Proteus vertical axis tidal stream power generator involving tow tests at speeds to 1.5 ms–1 in William Wright Dock on the Humber. The results are used to derive appropriate coefficients in the logisticcurve and to estimate the device’s annual electrical output.
Water Resource and Power Generation: An Alternative Formulation  [PDF]
Jack Robles
Theoretical Economics Letters (TEL) , 2012, DOI: 10.4236/tel.2012.23062
Abstract: Crampes and Moreaux [1] provide a two period model of competition between a hydrostation and a thermal station for the generation of electricity. We modify this model to make it more directly comparable with an infinite horizon model. The closed loop equilibrium is characterized.
The Economic Potential of Brewer’s Spent Grain (BSG) as a Biomass Feedstock  [PDF]
Jack Buffington
Advances in Chemical Engineering and Science (ACES) , 2014, DOI: 10.4236/aces.2014.43034

This paper analyzes a pro-forma economic market and supply chain system for the reuse of a lignocellulose (brewer’s spent grain) in an industrial biotechnology environment. An extant literature review was conducted, followed by a technical analysis of BSG, and the development of a supply chain system and economic market analysis based upon a participant brewing company and industry experts. In this paper, it was found that, even with the potential for future improvements in the conversion of brewer’s spent grain (BSG) from an efficiency standpoint, this industrial residual is supply chain prohibitive as a biofeedstock in comparison to other lignocellulose materials, therefore, centralized market relationships would not be advantageous for sellers and buyers. Future research should consider the viability of centralized supply chain structures for alternatives that may exist as future bio-feedstocks.

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