On the functioning and the efficiency of the emerging equity markets

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.In the present thesis a series of theoretical and empirical issues relating to the functioning and the efficiency of the emerging equity markets is investigated. The sample covers ten markets; four from the Latin America and six from the Asia, Asia- Pacific, for the period between 1976 to 1994. In particular, I investigate various aspects of the behavior of equity prices in emerging markets, focusing on whether financial markets in the emerging economies are efficient [as in Fama (1970b)] or exhibit seasonal patterns; whether they move together over time and any subsequent implications this long-run comovement may have for international portfolio diversification; how volatility in these markets behaves and whether there are volatility spill overs from one market to another; whether financial liberalization has increased or decreased equity market volatility; what factors are important in determining equity returns in emerging economies. The main results that emerge from the analysis suggest that prices in the markets of the sample do not follow Random Walks and exhibit seasonal patterns, such as the well known Monday-effect. Furthermore, common long-run trends were detected within regions, however, more detailed analysis suggested that benefits to international portfolio diversification are not eradicated in the long-run. Also, a meteor shower effect, i.e. volatility spill-overs, was detected for most markets

Geodesic motions versus hydrodynamic flows in a gravitating perfect fluid: Dynamical equivalence and consequences

Stimulated by the methods applied for the observational determination of masses in the central regions of the AGNs, we examine the conditions under which, in the interior of a gravitating perfect fluid source, the geodesic motions and the general relativistic hydrodynamic flows are dynamically equivalent to each other. Dynamical equivalence rests on the functional similarity between the corresponding (covariantly expressed) differential equations of motion and is obtained by conformal transformations. In this case, the spaces of the solutions of these two kinds of motion are isomorphic. In other words, given a solution to the problem "hydrodynamic flow in a perfect fluid", one can always construct a solution formally equivalent to the problem "geodesic motion of a fluid element" and vice versa. Accordingly, we show that, the observationally determined nuclear mass of the AGNs is being overestimated with respect to the real, physical one. We evaluate the corresponding mass-excess and show that it is not always negligible with respect to the mass ofthe central dark object, while, under circumstances, can be even larger than the rest-mass of the circumnuclear gas involved.Comment: LaTeX file, 22 page

Monetary policy and herd behavior: international evidence

This paper is motivated by the recent discussion on the need of market supervisors, regulators, and policy makers, to take into account the behavioral elements of market participant attitudes and psychological and cognitive biases when taking policy decisions. We contribute to the discussion by studying, for the first time, the relationship between conventional and unconventional central bank monetary policy and herd behavior in equity markets, and argue that the transmission channel, through which monetary policy may affect herd behavior, is economic expectations and investor sentiment. We combine a range of research methodologies to measure monetary policy, herd behavior, and their possible relation, and our results indicate that conventional and unconventional Fed monetary policy explains a significant percentage of US equity market herd behavior variance, while ECB monetary policy explains a lower percentage of Eurozone herding variance. Impulse Response Functions indicate that Fed’s conventional expansionary policy and non-standard policy reduces the levels of herding in the US equity market, while conventional ECB expansionary policy induces higher levels of herding in Spain and Italy. We also detect spill-over effects from Fed monetary policy to EU market herd behavior

Graphene/Carbon Dot Hybrid Thin Films Prepared by a Modified Langmuir-Schaefer Method

The special electronic, optical, thermal, and mechanical properties of graphene resulting from its 2D nature, as well as the ease of functionalizing it through a simple acid treatment, make graphene an ideal building block for the development of new hybrid nanostructures with well-defined dimensions and behavior. Such hybrids have great potential as active materials in applications such as gas storage, gas/liquid separation, photocatalysis, bioimaging, optoelectronics, and nanosensing. In this study, luminescent carbon dots (C-dots) were sandwiched between oxidized graphene sheets to form novel hybrid multilayer films. Our thin-film preparation approach combines self-assembly with the Langmuir-Schaefer deposition and uses graphene oxide nanosheets as template for grafting C-dots in a bidimensional array. Repeating the cycle results in a facile and low-cost layer-by-layer procedure for the formation of highly ordered hybrid multilayers, which were characterized by photoluminescence, UV-visible, X-ray photoelectron, and Raman spectroscopies, as well as X-ray diffraction and atomic force microscopy.</p

Development of a dynamic dust source map for NMME-DREAM v1.0 model based on MODIS Normalized Difference Vegetation Index (NDVI) over the Arabian Peninsula

We developed a time-dependent dust source map for the NMME Dust Regional Atmospheric Model (DREAM v1.0) based on the satellite MODIS Normalized Difference Vegetation Index (NDVI). Areas with NDVI&thinsp;&lt;0.1 are classified as active dust sources. The updated modeling system is tested for dust emission capabilities over SW Asia using a mesoscale model grid increment of 0.1∘×0.1∘ for a period of 1 year (2016). Our results indicate significant deviations in simulated aerosol optical depths (AODs) compared to the static dust source approach and general increase in dust loads over the selected domain. Comparison with MODIS AOD indicates a more realistic spatial distribution of dust in the dynamic source simulations compared to the static dust sources approach. The modeled AOD bias is improved from −0.140 to 0.083 for the case of dust events (i.e., for AOD&thinsp;&gt;0.25) and from −0.933 to −0.424 for dust episodes with AOD&thinsp;&gt;1. This new development can be easily applied to other time periods, models, and different areas worldwide for a local fine tuning of the parameterization and assessment of its performance.</p

Analysis of 3800-year-old Yersinia pestis genomes suggests Bronze Age origin for bubonic plague

该论文通过对青铜器时代的两个鼠疫杆菌分离株进行测序，深入剖析了鼠疫杆菌的历史。德国、俄罗斯、中国和瑞士等多国研究员共同参与了研究。这篇论文的第一作者是德国马克斯-普朗克研究所的考古遗传学专家Maria Spyrou。她和同事从俄罗斯墓穴中埋葬的九名古代人的牙齿样本入手，发现有两人感染鼠疫杆菌。之后，他们从这些个体中分离出距今约3800年的病原菌。在这项新研究中，研究人员利用液相捕获和Illumina鸟枪法测序技术，对青铜器时代的一名男子（RT5）的鼠疫杆菌和人类宿主序列进行测序，其中鼠疫杆菌基因组的平均覆盖度达到32倍。同时，他们还对另一名感染个体（RT6）的分离株进行测序，平均覆盖度为1.9倍。系统发育分析表明，RT5和RT6分离株是共同谱系的一部分，这个谱系的祖先是史上三次瘟疫大流行的罪魁祸首。除了众所周知的中世纪欧洲瘟疫大流行，鼠疫杆菌还曾造成公元6世纪的查士丁尼瘟疫和19世纪的中国大规模鼠疫。 马克斯-普朗克人类历史科学研究所的古病理学专家Kirsten Bos表示，这些结果表明“具有传播潜力的瘟疫存在的时间比我们想象得更久。”Bos是这篇论文的通讯作者之一。【Abstract】The origin of Yersinia pestis and the early stages of its evolution are fundamental subjects of investigation given its high virulence and mortality that resulted from past pandemics. Although the earliest evidence of Y. pestis infections in humans has been identified in Late Neolithic/Bronze Age Eurasia (LNBA 5000–3500y BP), these strains lack key genetic components required for flea adaptation, thus making their mode of transmission and disease presentation in humans unclear. Here, we reconstruct ancient Y. pestis genomes from individuals associated with the Late Bronze Age period (~3800 BP) in the Samara region of modern-day Russia. We show clear distinctions between our new strains and the LNBA lineage, and suggest that the full ability for flea-mediated transmission causing bubonic plague evolved more than 1000 years earlier than previously suggested. Finally, we propose that several Y. pestis lineages were established during the Bronze Age, some of which persist to the present day.We thank Cosimo Posth, Marcel Keller, Michal Feldman and Wolfgang Haak for useful insights to the manuscript, as well as Alexander Immel and Stephen Clayton for computational support. In addition, we are thankful to Guido Brandt, Antje Wissgott and Cäcilia Freund for laboratory support. M.A.S., A.H., K.I.B. and J.K. were supported by the ERC starting grant APGREID, and by the Max Planck Society. C.C.W. was supported by the Max Planck Society and the Nanqiang Outstanding Young Talents Program of Xiamen University. D.K. was supported by a Marie Heim-Vögtlin grant from the Swiss National Science Foundation

A facile approach to hydrophilic oxidized fullerenes and their derivatives as cytotoxic agents and supports for nanobiocatalytic systems

A facile, environment-friendly, versatile and reproducible approach to the successful oxidation of fullerenes (oxC60) and the formation of highly hydrophilic fullerene derivatives is introduced. This synthesis relies on the widely known Staudenmaier’s method for the oxidation of graphite, to produce both epoxy and hydroxy groups on the surface of fullerenes (C60) and thereby improve the solubility of the fullerene in polar solvents (e.g. water). The presence of epoxy groups allows for further functionalization via nucleophilic substitution reactions to generate new fullerene derivatives, which can potentially lead to a wealth of applications in the areas of medicine, biology, and composite materials. In order to justify the potential of oxidized C60 derivatives for bio-applications, we investigated their cytotoxicity in vitro as well as their utilization as support in biocatalysis applications, taking the immobilization of laccase for the decolorization of synthetic industrial dyes as a trial case.Peer ReviewedPostprint (published version

K-Space at TRECVID 2008

In this paper we describe K-Space’s participation in TRECVid 2008 in the interactive search task. For 2008 the K-Space group performed one of the largest interactive video information retrieval experiments conducted in a laboratory setting. We had three institutions participating in a multi-site multi-system experiment. In total 36 users participated, 12 each from Dublin City University (DCU, Ireland), University of Glasgow (GU, Scotland) and Centrum Wiskunde and Informatica (CWI, the Netherlands). Three user interfaces were developed, two from DCU which were also used in 2007 as well as an interface from GU. All interfaces leveraged the same search service. Using a latin squares arrangement, each user conducted 12 topics, leading in total to 6 runs per site, 18 in total. We officially submitted for evaluation 3 of these runs to NIST with an additional expert run using a 4th system. Our submitted runs performed around the median. In this paper we will present an overview of the search system utilized, the experimental setup and a preliminary analysis of our results

Low-lying level structure of 56^{56}Cu and its implications on the rp process

The low-lying energy levels of proton-rich $^{56}$Cu have been extracted using in-beam $\gamma$-ray spectroscopy with the state-of-the-art $\gamma$-ray tracking array GRETINA in conjunction with the S800 spectrograph at the National Superconducting Cyclotron Laboratory at Michigan State University. Excited states in $^{56}$Cu serve as resonances in the $^{55}$Ni(p,$\gamma$)$^{56}$Cu reaction, which is a part of the rp-process in type I x-ray bursts. To resolve existing ambiguities in the reaction Q-value, a more localized IMME mass fit is used resulting in $Q=639\pm82$~keV. We derive the first experimentally-constrained thermonuclear reaction rate for $^{55}$Ni(p,$\gamma$)$^{56}$Cu. We find that, with this new rate, the rp-process may bypass the $^{56}$Ni waiting point via the $^{55}$Ni(p,$\gamma$) reaction for typical x-ray burst conditions with a branching of up to $\sim$40$\%$. We also identify additional nuclear physics uncertainties that need to be addressed before drawing final conclusions about the rp-process reaction flow in the $^{56}$Ni region.Comment: 8 pages, accepted for Phys. Rev.