175 research outputs found
An Underwater Channel Model and Chirp Slope Keying Modulation Scheme Performance
Chirp-Slope Keying (CSK) is a new and innovative digital modulation scheme for underwater data transmission. The underwater environment brings up several challenges to the manufacturing and operation of communication systems. This thesis shows through analysis and simulations the effectiveness of Chirp-Slope Keying (CSK) in providing a satisfying performance in underwater communication. The experiment consists of modulating a chirp slope by binary numbers (representing our data). \u270\u27 is represented by a linear- down chirp and \u271\u27 is represented by a linear-up chirp. The received data is first processed by a correlator receiver. Then, the detection of either binary symbol is obtained by the comparison to a threshold. Simulation results for numerous signal-to-noise ratios show that CSK provides satisfying performance for underwater data transmission. The Mississippi gulf coast shallow water Data collected from the National Oceanic and Atmospheric Administration (NOAA), (see appendix), allow us to accurately generate a laboratory model for the channel of interest
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The Impacts of Authorised Dictatorial Discourse on Heritage Management - Case study: South Korea's Military Dictatorship Era 1961 - 1988
This thesis investigates some of the impacts a ‘dictatorship’ can have on the management and uses of heritage sites. More specifically, it endeavours to examine how a dictator’s interests in certain heritage sites and particular territories can affect how heritage becomes preserved and promoted in both the medium and long-terms. The relationship between heritage and dictatorship has, arguably, been relatively under-studied compared to research on the nation-state. In recognising the importance of understanding how different political systems (in this case exemplified by dictatorial regimes) can have various and particular outcomes on heritage, this study will develop the concept of ‘Authorised Dictatorial Discourse’ (ADD) as an original contribution to the field of Heritage Studies. It stems from Laurajane Smith’s (2006) seminal works on Authorised Heritage Discourse and her argument about how authorities in the form of decision-making bodies have medium and long term impacts on the preservation and promotion of heritage sites and that this happens detached from the wider public. I argue that her concept is based on democratic political systems.
To develop the concept of ADD, South Korea’s Military Dictatorship Era (1961-1988) will be used as the central case study. The two dictators (Park Chung Hee and Chun Doo Hwan) orchestrated strictly controlled and very particular heritage and territory polices. Their authoritarian decisions debatably had profound impacts, making their cases very suitable for further analysis. To provide more detailed insights, this dissertation will analyse six heritage sites in terms of how they were targeted by the two dictators as tools of narrative constructions. These case studies will be used as an analytical lens to: 1) cast light on how and the extent to which the politics of heritage and the politics of territory were interlinked and influenced the management and uses of heritage, 2) reflect on the common pattern of heritage and territorial management during dictatorships, and 3) argue how the current AHD (Smith 2006) need to be problematised in terms of its remit
Selective resolution of phonon modes in STM-IETS on clean and oxygen-adsorbed Cu(100) surfaces
The observation of surface phonon dispersion using local probes can provide
important information related to local structural and thermal properties. In
this study, surface phonon modes on a Cu(100) surface were measured using the
inelastic tunneling spectroscopy of scanning tunneling microscopy (STM-IETS)
with atomically sharp tips. Different phonon modes were selectively measured
depending on the structures of the probing tips or the surfaces. Two different
surface phonon modes, at 19.0 meV on a clean Cu(100) surface and at 13.5 meV on
an oxygen-adsorbed Cu(100) surface, are explained by the selection rules.
Additionally, the spatial variation in STM-IETS showed surface stress
relaxation.Comment: 19 pages, 4 figures, supplementary material with 2 figure
A fully Bayesian semi-parametric scalar-on-function regression (SoFR) with measurement error using instrumental variables
Wearable devices such as the ActiGraph are now commonly used in health
studies to monitor or track physical activity. This trend aligns well with the
growing need to accurately assess the effects of physical activity on health
outcomes such as obesity. When accessing the association between these
device-based physical activity measures with health outcomes such as body mass
index, the device-based data is considered functions, while the outcome is a
scalar-valued. The regression model applied in these settings is the
scalar-on-function regression (SoFR). Most estimation approaches in SoFR assume
that the functional covariates are precisely observed, or the measurement
errors are considered random errors. Violation of this assumption can lead to
both under-estimation of the model parameters and sub-optimal analysis. The
literature on a measurement corrected approach in SoFR is sparse in the
non-Bayesian literature and virtually non-existent in the Bayesian literature.
This paper considers a fully nonparametric Bayesian measurement error corrected
SoFR model that relaxes all the constraining assumptions often made in these
models. Our estimation relies on an instrumental variable (IV) to identify the
measurement error model. Finally, we introduce an IV quality scalar parameter
that is jointly estimated along with all model parameters. Our method is easy
to implement, and we demonstrate its finite sample properties through an
extensive simulation. Finally, the developed methods are applied to the
National Health and Examination Survey to assess the relationship between
wearable-device-based measures of physical activity and body mass index among
adults living in the United States
Assessment of the Efficiency of Insecticide Paint and Impregnated Nets on Tsetse Populations: Preliminary Study in Forest Relics of Abidjan, Côte d’Ivoire
Glossina palpalis palpalis is the main vector of human and animal trypanosomiasis in Côte d’Ivoire. This species, being the only tsetse species in the city of Abidjan, is hosted by the National park of Banco located in the middle of Abidjan, the zoological park and in a relic forest within the University of Nangui-Abrogoua, both in Abidjan. A programme for the elimination of these suburban tsetse populations has been initiated, in the context of which various tsetse control tools have been evaluated. In the zoological park, insecticidal paint (Inesfly®) was applied around the animal cages, and then supplemented with insecticide-impregnated netting around the larger animal cages. Tsetse population densities were monitored with Vavoua-style traps both inside the zoological park and in the site of University Nangui Abrogoua used as control site. Tsetse densities in the traps fell by over 90% following application of the insecticidal paint, and declined to zero after adding the insecticide impregnated nets in both study sites. The study confirms the close contact between tsetse populations from the zoological park and the University Nangui Abrogoua area, and shows that the sequential use of insecticide paint and impregnated nets can be effective for tsetse control
Impact des filets imprégnés de deltaméthrine sur les populations de glossines au Parc zoologique d'Abidjan et à l'Université Nangui Abrogoua.
Des enquêtes entomologiques antérieures réalisées à Abidjan dans le Parc National du Banco et les reliques forestières du Parc zoologique (Zoo) d'Abidjan et de l'Université Nangui Abrogoua (UNA), ont montré la présence de Glossina palpalis palpalis, vecteur majeur des trypanosomoses humaine et animale en Côte d'Ivoire. Face au risque encouru par les populations humaines et animales de cette ville, une lute antivectorielle basée sur une nouvelle technique, les filets imprégnés de deltaméthrine a été mise en place au Zoo. L'Université Nangui Abrogoua a servi de site témoin. L'objectif a été d'évaluer l'impact de ces filets dans le cadre d'une lutte antivectorielle au Zoo d'Abidjan. Avant la pose des filets en février 2011, des captures de glossines ont été effectuées de novembre 2010 à janvier 2011 avec 12 pièges "Vavoua" posés Durant quatre jours consécutifs sur les différents sites. Les évaluations ont débuté après la crise post-électorale, en septembre 2011. Le site témoin a été perturbé par les travaux de réaménagement, qui ont détruit une partie de l'habitat des glossines. Au Zoo, la DAP a chuté brusquement de 1,8 à 0 glossine/ piège/jour. A l'Université, la densité a baissé progressivement, de 0,4 à 0,2 glossine/ piège/ jour, avant de s'annuler. L'utilisation des filets imprégnés de deltaméthrine a été très efficace, cet outil pourrait constituer une option supplémentaire dans la lutte contre les trypanosomoses.Mots clés: lutte anti-vectorielle, Filets, Parc zoologique, l'Université Nangui Abrogoua. Impact of nets impregnated with deltamethrin on tsetse populations in Abidjan Zoological Park and the Nangui Abrogouab University. Using nets impregnated with deltamethrin against tsetsePrevious entomological surveys carried out in Abidjan in the Banco National Park and forest relics of Abidjan zoological Park and the Nangui Abrogoua University showed the presence of Glossina palpalis palpalis, main vector of human and animal trypanosomiasis in Ivory Coast. Cope with the risk to human and animal populations of this city, vector control based on a new technique that is nets impregnated with deltamethrin have been set up at the Zoo. The University Nangui Abrogoua served as a control site. The objective was to evaluate the impact of deltamethrin impregnated nets in vector control of Abidjan Zoo. Before the introduction of insecticide-treated nets in February 2011, the flies catches were conducted from November 2010 to January 2011 with 12 "Vavoua" traps laid during four consecutive days in different sites. Assessments began after the post-election crisis in September 2011. The control site was disrupted by the redevelopment, which destroyed part of the tsetse habitat. At The Zoo, the DAP fell sharply from 1.8 to 0 of tsetse / trap / day. The DAP has dropped sharply from 1.8 to 0 of tsetse / trap / day. At the University, the density decreased gradually from 0.4 to 0.2 tsetse / trap / day, before cancel. The use of nets treated with deltamethrin has been very effective, this tool could be an additional option in the fight against trypanosomiasis.Keywords: nets, zoological park, Nangui Abrogoua University, vector control
CQDs embed g-C3N4 photocatalyst in dye removal and hydrogen evolution : An insight review
Recent research has highlighted heterogeneous photocatalysts as a feasible contender for addressing energy shortages and environmental cleanup. One of the best semiconducting photocatalysts used in wastewater treatment, disinfection, and energy evolution is graphitic carbon nitrate (g-C3N4). Researchers have used carbon quantum dots (CQDs) to maximize and enhance the photocatalytic activity of g-C3N4 and to get over the material's limits due to photoinduced charges, partial surface area, and insufficient light-capturing difficulties. In this context, the fundamentals of CQDs and g-C3N4 are described in length, along with their structural state, synthesis, and modification techniques. The classification, manufacturing procedure, and characterization of CQDs/g-C3N4 are then highlighted in this paper. Following that, it is shown how CQDs/g-C3N4 photocatalysts are used in dye removal and hydrogen evolution studies. The discussion of CQDs/g-C3N4's present hurdles, unmet needs, and future research prospects concludes while keeping in mind their practical applications. This study shows that by embedding CQDs, the influence of charges, morphological modification, and textural quality of g-C3N4 have been altered. It is anticipated that this review will offer a practical overview and comprehension of CQDs embedded with g-C3N4 photocatalysts in order to promote their utilization. The ultimate goal of this review may be to impart a fundamental understanding of photocatalysis while also providing an expository evaluation of the most recent advancements in g-C3N4/CQDs photocatalysts in the sectors of energy and environmental security
Rapidly cycling Lgr5+ stem cells are exquisitely sensitive to extrinsic dietary factors that modulate colon cancer risk
The majority of colon tumors are driven by aberrant Wnt signaling in intestinal stem cells, which mediates an efficient route toward initiating intestinal cancer. Natural lipophilic polyphenols and long-chain polyunsaturated fatty acids (PUFAs) generally suppress Wnt- and NF-κB- (nuclear factor-κ light-chain enhancer of activated B-cell) related pathways. However, the effects of these extrinsic agents on colonic leucine-rich repeat-containing G-protein-coupled receptor 5-positive (Lgr5(+)) stem cells, the cells of origin of colon cancer, have not been documented to date. Therefore, we examined the effect of n-3 PUFA and polyphenol (curcumin) combination on Lgr5(+) stem cells during tumor initiation and progression in the colon compared with an n-6 PUFA-enriched control diet. Lgr5-EGFP-IRES-(creERT2) knock-in mice were fed diets containing n-6 PUFA (control), n-3 PUFA, n-6 PUFA+curcumin or n-3 PUFA+curcumin for 3 weeks, followed by 6 azoxymethane (AOM) injections, and terminated 17 weeks after the last injection. To further elucidate the effects of the dietary bioactives at the tumor initiation stage, Lgr5(+) stem cells were also assessed at 12 and 24 h post AOM injection. Only n-3 PUFA+curcumin feeding reduced nuclear β-catenin in aberrant crypt foci (by threefold) compared with control at the progression time point. n-3 PUFA+curcumin synergistically increased targeted apoptosis in DNA-damaged Lgr5(+) stem cells by 4.5-fold compared with control at 12 h and maximally reduced damaged Lgr5(+) stem cells at 24 h, down to the level observed in saline-treated mice. Finally, RNAseq analysis indicated that p53 signaling in Lgr5(+) stem cells from mice exposed to AOM was uniquely upregulated only following n-3 PUFA+curcumin cotreatment. These novel findings demonstrate that Lgr5(+) stem cells are uniquely responsive to external dietary cues following the induction of DNA damage, providing a therapeutic strategy for eliminating damaged Lgr5(+) stem cells to reduce colon cancer initiation
Performance evaluation of dye wastewater treatment technologies: A review
Dye wastewater released from several dyes induced industries are harmful towards the living, non-living environment and human. Consequently, existence of dye in water bodies is becoming a rising concern to environmentalists and citizens. Dye wastewater should be treated prior to release in an open water body to minimize its negative impacts. A long term sustainable and efficient treatment methods should be established to reduce and overcome the impacts. Although there have been significant advances in the management and treatment of such effluent using physical, chemical and biological methods. However, due to lack of information on effective dye removal methods, it is difficult to decide on a single unique technique that resolves the prevailing dye wastewater. Therefore, this paper reviews recent research on various (physical, chemical, biological, advanced oxidation process (AOPs) and hybrid) dye removal methods to compare efficiency, evaluation performance, merits and demerits. Among the existing methods, most of them have a common disadvantage which is the generation of secondary pollutes, takes long time and costly. This paper especially highlights AOPs method for dye removal as these are known as one of the promising and most effective dye removal techniques these days. This paper also suggests the application of AOPs methods possess the best performance in terms of faster dye removing as well as cost effective, time oriented and environmentally friendly. Additionally, this paper addressed the difficulties and future prospects of this emerging method that links to sustainable development
Management of anastrozole-induced bone loss in breast cancer patients with oral risedronate: results from the ARBI prospective clinical trial
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