Risk Without Return

Risk-only investment strategies have been growing in popularity as traditional in- vestment strategies have fallen short of return targets over the last decade. However, risk-based investors should be aware of four things. First, theoretical considerations and empirical studies show that apparently dictinct risk-based investment strategies are manifestations of a single effect. Second, turnover and associated transaction costs can be a substantial drag on return. Third, capital diversification benefits may be reduced. Fourth, there is an apparent connection between performance and risk diversification. To analyze risk diversification benefits in a consistent way, we introduce the Risk Diversification Index (RDI) which measures risk concentrations and complements the Herfindahl-Herschman Index (HHI) for capital concentrations

Controls on Cyclic Formation of Quaternary Early Diagenetic Dolomite

The origin of sedimentary dolomite and the factors that control its formation within the geological record remain speculative. In most models, dolomite formation is linked to evaporative conditions, high water temperature, increasing Mg/Ca ratio, increasing alkalinity, and high amounts of biomass. Here we challenge these archetypal views, by documenting a case example of Quaternary dolomite which formed in Lake Van at constantly low temperature (<4°C) and without direct control of the latter conditions. Dolomite occurs within highstand sediments related to suborbital climate variability (Dansgaard‐Oeschger cycles). We propose that dolomite precipitation is a product of a microbially influenced process, triggered by ecological stress, resulting from reventilation of the water‐sediment interface. Independently from the validity of this hypothesis, our results call for a reevaluation of the paleoenvironmental conditions often invoked for early diagenetic dolomite‐rich intervals within sedimentary sequences and for caution when interpreting time series of subrecent lacustrine carbonates

SOFT: A synthetic synchrotron diagnostic for runaway electrons

Improved understanding of the dynamics of runaway electrons can be obtained by measurement and interpretation of their synchrotron radiation emission. Models for synchrotron radiation emitted by relativistic electrons are well established, but the question of how various geometric effects -- such as magnetic field inhomogeneity and camera placement -- influence the synchrotron measurements and their interpretation remains open. In this paper we address this issue by simulating synchrotron images and spectra using the new synthetic synchrotron diagnostic tool SOFT (Synchrotron-detecting Orbit Following Toolkit). We identify the key parameters influencing the synchrotron radiation spot and present scans in those parameters. Using a runaway electron distribution function obtained by Fokker-Planck simulations for parameters from an Alcator C-Mod discharge, we demonstrate that the corresponding synchrotron image is well-reproduced by SOFT simulations, and we explain how it can be understood in terms of the parameter scans. Geometric effects are shown to significantly influence the synchrotron spectrum, and we show that inherent inconsistencies in a simple emission model (i.e. not modeling detection) can lead to incorrect interpretation of the images.Comment: 24 pages, 12 figure

DETERMINATION OF TOTAL TANIN CONTENTS OF Terminalia Catappa, L. LEAF EXTRACT AND TEST OF ITS ABILITY AS A COMPLEXION AGENT OF Fe (III)

A study of the essential oil content in basil (Ocimum sanctum) and red lemongrass (Cymbopogon nardus L. Rendle) originally grown in Flores island has been conducted. The purpose of this study was to identify the chemotype of the essential oils obtained over stahl distillation using GC-MS. The Ocimum mainly consisted of 55% eugenol following by minor trans-alfa-bergometena, patchulana, and linalool. Meanwhile, the chemotype of the red lemongrass (Cymbopogon nardus L. rendle) were citronellol (22%), citronella, cyclohexamethanol, and viridiflorol

Far-infrared induced current in a ballistic channel -- potential barrier structure

We consider electron transport in a ballistic multi-mode channel structure in the presence of a transversely polarized far-infrared (FIR) field. The channel structure consists of a long resonance region connected to an adiabatic widening with a potential barrier at the end. At frequencies that match the mode energy separation in the resonance region we find distinct peaks in the photocurrent, caused by Rabi oscillations in the mode population. For an experimental situation in which the width of the channel is tunable via gates, we propose a method for reconstructing the spectrum of propagating modes, without having to use a tunable FIR source. With this method the change in the spectrum as the gate voltage is varied can be monitored.Comment: Submitted to Phys. Rev.

Current driven magnetization dynamics in helical spin density waves

A mechanism is proposed for manipulating the magnetic state of a helical spin density wave using a current. In this paper, we show that a current through a bulk system with a helical spin density wave induces a spin transfer torque, giving rise to a rotation of the order parameter.The use of spin transfer torque to manipulate the magnetization in bulk systems does not suffer from the obstacles seen for magnetization reversal using interface spin transfer torque in multilayered systems. We demonstrate the effect by a quantitative calculation of the current induced magnetization dynamics of Erbium. Finally we propose a setup for experimental verification.Comment: In the previous version of this paper was a small numerical mistake made when evaluating equation 3 and 9. The number of digits given in the calculation of the torque current tensor is reduced to better represent the accuracy of the calculation. A slightly modified paper have been published in Phys. Rev. Lett. 96, 256601 (2006) 4 pages 3 figure

Review: Solid Dispersion Technique for Enhancement of Solubility of Poorly Soluble Drug

Nearly 40% of novel drugs comes in pharmaceutical industries are showing poor capability of solubilization in water. Therefore enhancing the solubilization of such drugs in water to enhance their bioavailability be the major challenge to formulation scientists. So the preparation of solid dispersion from the drug which shows poor solubility in water with carriers having good water solubility has decrease the occurrence of such problems and increase dissolution. Hence solid dispersion found to be attention-grabbing method for solubility enhancing of drugs which showing poor solubility in water. This review, shows an overview on the different solid dispersion types, rationale, their advantages, limitations, manufacturing processes as well as its characterization methods

GAS CHROMATOGRAPHY - MASS SPECTROMETRY ANALYSIS, INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY INVESTIGATION, AND ANTIMICROBIAL SCREENING OF CAESALPINIA BONDUCELLA (L.) ROXB SEED KERNEL

Objective: The objective of this study was to determine heavy metals using inductively coupled plasma mass spectrometry (ICP-MS) and phytochemical constituents of methanol extract of Caesalpinia bonducella seed kernel using gas chromatography - mass spectrometry (GC-MS). Methods: In GC-MS investigation, 95% methanol extract of C. bonducella seed kernel was performed on JEOL GC MATE ΙΙ, column HP 5 MS, and Quadruple, double-focusing mass analyzer. Determination of heavy metals from C. bonducella powder was performed using Thermo scientific I CAP Q instrument, for plant powder digestion Anton Paar Microwave model: Multiwave 300 was used. Antimicrobial activity was evaluated using microdilutions broth method. Results: GC-MS analysis of methanol extract of C. bonducella seed kernel has shown 11 different phytoconstituents. ICP-MS analysis has shown the concentration of ten heavy metals in C. bonducella seed kernel as follows: Cr 1.5 ppm, Fe 72.72 ppm, Co 0.33 ppm, Ni 0.03 ppm, Cu 10.73 ppm, Zn 18.44 ppm, As 0.03 ppm, Cd 0.02 ppm, and Pb 0.58 ppm. Conclusion: Result showed that the plant is safe to use from toxic heavy metals such as As, Cd, and Pb. It is suitable to check frequently the heavy metal content in the plant used in traditional medicines before given to patients

Bayes' theorem and its applications in animal behaviour

Bayesian decision theory can be used to model animal behaviour. In this paper we give an overview of the theoretical concepts in such models. We also review the biological contexts in which Bayesian models have been applied, and outline some directions where future studies would be useful. Bayesian decision theory, when applied to animal behaviour, is based on the assumption that the individual has some sort of "prior opinion" of the possible states of the world. This may, for example, be a previously experienced distribution of qualities of food patches, or qualities of potential mates. The animal is then assumed to be able use sampling information to arrive at a "posterior opinion", concerning e.g. the quality of a given food patch, or the average qualities of mates in a year. A correctly formulated Bayesian model predicts how animals may combine previous experience with sampling information to make optimal decisions. We argue that the assumption that animals may have "prior opinions" is reasonable. Their priors may come from one or both of two sources: either from their own individual experience, gained while sampling the environment, or from an adaptation to the environment experienced by previous generations. This means that we should often expect to see "Bayesian-like" decision-making in nature