Search for the BcB_{c} meson in hadronic Z decays

Out of 3.1 million hadronic Z decays collected by the ALEPH detector between 1991 and 1994 a sample of approximately 600 J/Psi candidates decaying into e+e- or mu+mu- are selected. From these events, a search for the Bc meson decaying into the channels (J/psi pi+), (J/psi e+ nu) and (J/psi mu+ nu) is performed. This search results in the observation of 0, 1 and 1 candidate in each of these channels respectively, with 0.32, 0.17 and 0.13 background event expected. This allows the following 90 \% confidence level upper limits to be derived: G ( Z->Bc X)/G ( Z->q q) Br (Bc->J\psi pi+) Bc X)/G ( Z->q q) Br (Bc->J\psi l nu ) < 7 10**-5

A wide bandwidth free-electron laser with mode locking using current modulation

A new scheme for mode locking a free-electron laser (FEL) amplifier is proposed based on electron beam current modulation. It is found that certain properties of the original concept (Thompson and McNeil 2008 Phys. Rev. Lett. 100 203901), based on the energy modulation of electrons, are improved, including the spectral brightness of the source and the purity of the series of short pulses. Numerical comparisons are made between the new and old schemes and between a mode-locked FEL and a self-amplified spontaneous emission FEL. Illustrative examples using a hypothetical mode-locked FEL amplifier are provided. The ability to generate intense coherent radiation with a large bandwidth is demonstrated

The value of enhancing nutrient bioavailability of lentils: the Sri Lankan scenario

Lentil (Lens culinaris Medic.) is a pulse crop that belongs to the family Leguminosae. Lentils are rich in proteins, have 18 of the 20 amino acids including all 8 essential amino acids and provide a number of essential minerals and vitamins. Thus, lentils occupy an important place in the human diet, especially in developing countries, as a rich source of protein, vitamins and minerals. Although in many developing countries in Asia rice contributes significantly to human daily energy and nutritional requirements, its amino acid profile shows that rice lacks some essential amino acids. Therefore, given their rich composition of amino acids, lentils could act as an ideal supplement for rice-based diets. Although all red lentils are imported, they are the most widely consumed pulse among Sri Lankans. Red lentil consumption levels are significantly greater in the estate sector where the prevalence of under nutrition is high. Thus, this review was undertaken to understand the potential role of lentils in the Sri Lankan diet and how lentils can potentially be utilized to meet the nutritional needs of Sri Lankans. The study was based on an extensive literature review and information obtained through personal interviews with key participants in the red lentil industry of Sri Lanka. It was evident that red lentils are a rich source of nutrients, especially micro-nutrients, but their bioavailability is poor due to the presence of multiple anti-nutritive factors such as protease inhibitors, phenolic compounds and phytates. Although bioavailability of nutrients can be enhanced by changing food processing techniques, fortification and bio-fortification, lentil cooking patterns in Sri Lanka pose difficulties in adopting changed food processing techniques and fortification. Thus, bio-fortification would be the most viable option for enhancing nutrient availability in lentils. Since Sri Lanka does not produce lentils, such initiatives may have to be undertaken in exporting countries or in collaboration with international agricultural research centres. Any strategic investments in breeding new lentil varieties with high bioavailability would provide exporting countries a unique competitive edge in export markets. Such improvements would meet the nutritional needs, not only of Sri Lankans, but also of millions other Asian consumers who face similar nutritional challenges.Key words: Bioavailability, Consumption, Nutrition, lentils, Sri Lanka

The value of enhancing nutrient bioavailability of lentils: The Sri Lankan scenario

Lentil (Lens culinaris Medic.) is a pulse crop that belongs to the family Leguminosae. Lentils are rich in proteins, have 18 of the 20 amino acids including all 8 essential amino acids and provide a number of essential minerals and vitamins. Thus, lentils occupy an important place in the human diet, especially in developing countries, as a rich source of protein, vitamins and minerals. Although in many developing countries in Asia rice contributes significantly to human daily energy and nutritional requirements, its amino acid profile shows that rice lacks some essential amino acids. Therefore, given their rich composition of amino acids, lentils could act as an ideal supplement for rice-based diets. Although all red lentils are imported, they are the most widely consumed pulse among Sri Lankans. Red lentil consumption levels are significantly greater in the estate sector where the prevalence of under nutrition is high. Thus, this review was undertaken to understand the potential role of lentils in the Sri Lankan diet and how lentils can potentially be utilized to meet the nutritional needs of Sri Lankans. The study was based on an extensive literature review and information obtained through personal interviews with key participants in the red lentil industry of Sri Lanka. It was evident that red lentils are a rich source of nutrients, especially micro-nutrients, but their bioavailability is poor due to the presence of multiple anti-nutritive factors such as protease inhibitors, phenolic compounds and phytates. Although bioavailability of nutrients can be enhanced by changing food processing techniques, fortification and bio-fortification, lentil cooking patterns in Sri Lanka pose difficulties in adopting changed food processing techniques and fortification. Thus, bio-fortification would be the most viable option for enhancing nutrient availability in lentils. Since Sri Lanka does not produce lentils, such initiatives may have to be undertaken in exporting countries or in collaboration with international agricultural research centres. Any strategic investments in breeding new lentil varieties with high bioavailability would provide exporting countries a unique competitive edge in export markets. Such improvements would meet the nutritional needs, not only of Sri Lankans, but also of millions other Asian consumers who face similar nutritional challenges.Key words: Bioavailability, Consumption, Nutrition, lentils, Sri Lanka

PACE: Pattern Accurate Computationally Efficient Bootstrapping for Timely Discovery of Cyber-Security Concepts

Public disclosure of important security information, such as knowledge of vulnerabilities or exploits, often occurs in blogs, tweets, mailing lists, and other online sources months before proper classification into structured databases. In order to facilitate timely discovery of such knowledge, we propose a novel semi-supervised learning algorithm, PACE, for identifying and classifying relevant entities in text sources. The main contribution of this paper is an enhancement of the traditional bootstrapping method for entity extraction by employing a time-memory trade-off that simultaneously circumvents a costly corpus search while strengthening pattern nomination, which should increase accuracy. An implementation in the cyber-security domain is discussed as well as challenges to Natural Language Processing imposed by the security domain.Comment: 6 pages, 3 figures, ieeeTran conference. International Conference on Machine Learning and Applications 201

The Electrosphere of Macroscopic "Quark Nuclei": A Source for Diffuse MeV Emissions from Dark Matter

Using a Thomas-Fermi model, we calculate the structure of the electrosphere of the quark antimatter nuggets postulated to comprise much of the dark matter. This provides a single self-consistent density profile from ultrarelativistic densities to the nonrelativistic Boltzmann regime that use to present microscopically justified calculations of several properties of the nuggets, including their net charge, and the ratio of MeV to 511 keV emissions from electron annihilation. We find that the calculated parameters agree with previous phenomenological estimates based on the observational supposition that the nuggets are a source of several unexplained diffuse emissions from the Galaxy. As no phenomenological parameters are required to describe these observations, the calculation provides another nontrivial verification of the dark-matter proposal. The structure of the electrosphere is quite general and will also be valid at the surface of strange-quark stars, should they exist.Comment: 20 Pages, REVTeX4.

Theoretical Sensitivity Analysis for Quantitative Operational Risk Management

We study the asymptotic behavior of the difference between the values at risk VaR(L) and VaR(L+S) for heavy tailed random variables L and S for application in sensitivity analysis of quantitative operational risk management within the framework of the advanced measurement approach of Basel II (and III). Here L describes the loss amount of the present risk profile and S describes the loss amount caused by an additional loss factor. We obtain different types of results according to the relative magnitudes of the thicknesses of the tails of L and S. In particular, if the tail of S is sufficiently thinner than the tail of L, then the difference between prior and posterior risk amounts VaR(L+S) - VaR(L) is asymptotically equivalent to the expectation (expected loss) of S.Comment: 21 pages, 1 figure, 4 tables, forthcoming in International Journal of Theoretical and Applied Finance (IJTAF

WMAP Haze: Directly Observing Dark Matter?

In this paper we show that dark matter in the form of dense matter/antimatter nuggets could provide a natural and unified explanation for several distinct bands of diffuse radiation from the core of the Galaxy spanning over 12 orders of magnitude in frequency. We fix all of the phenomenological properties of this model by matching to x-ray observations in the keV band, and then calculate the unambiguously predicted thermal emission in the microwave band, at frequencies smaller by 10 orders of magnitude. Remarkably, the intensity and spectrum of the emitted thermal radiation are consistent with--and could entirely explain--the so-called "WMAP haze": a diffuse microwave excess observed from the core of our Galaxy by the Wilkinson Microwave Anisotropy Probe (WMAP). This provides another strong constraint of our proposal, and a remarkable nontrivial validation. If correct, our proposal identifies the nature of the dark matter, explains baryogenesis, and provides a means to directly probe the matter distribution in our Galaxy by analyzing several different types of diffuse emissions.Comment: 16 pages, REVTeX4. Updated to correspond with published version: includes additional appendices discussing finite-size effect

Capital allocation for credit portfolios with kernel estimators

Determining contributions by sub-portfolios or single exposures to portfolio-wide economic capital for credit risk is an important risk measurement task. Often economic capital is measured as Value-at-Risk (VaR) of the portfolio loss distribution. For many of the credit portfolio risk models used in practice, the VaR contributions then have to be estimated from Monte Carlo samples. In the context of a partly continuous loss distribution (i.e. continuous except for a positive point mass on zero), we investigate how to combine kernel estimation methods with importance sampling to achieve more efficient (i.e. less volatile) estimation of VaR contributions.Comment: 22 pages, 12 tables, 1 figure, some amendment

The Roles of PPARs in the Fetal Origins of Metabolic Health and Disease

Beyond the short-term effects on fertility, there is increasing evidence that obesity or the consumption of an inappropriate diet by the mother during pregnancy adversely affects the long-term health of her offspring. PPAR and RXR isotypes are widely expressed in reproductive tissues and in the developing fetus. Through their interactions with fatty acids, they may mediate adaptive responses to the changes in the maternal diet. In the maturing follicle, PPAR-γ has an important role in the granulosa cells that surround the maturing oocyte. After fertilisation, PPAR-γ and PPAR-β/δ are essential regulators of placentation and the subsequent development of key metabolic tissues such as skeletal muscle and adipose cells. Activation of PPAR-γ and PPAR-β/δ during fetal development has the potential to modify the growth and development of these tissues. PPAR-α is expressed at low levels in the fetal liver, however, this expression may be important, as changes in the methylation of DNA in its promoter region are reported to take place during this period of development. This epigenetic modification then programmes subsequent expression. These findings suggest that two separate PPAR-dependent mechanisms may be involved in the fetal adaptations to the maternal diet, one, mediated by PPAR-γ and PPAR-β/δ, regulating cell growth and differentiation; and another adapting long-term lipid metabolism via epigenetic changes in PPAR-α to optimise postnatal survival