Estimating Drift Parameters in a Fractional Ornstein Uhlenbeck Process with Periodic Mean

We construct a least squares estimator for the drift parameters of a fractional Ornstein Uhlenbeck process with periodic mean function and long range dependence. For this estimator we prove consistency and asymptotic normality. In contrast to the classical fractional Ornstein Uhlenbeck process without periodic mean function the rate of convergence is slower depending on the Hurst parameter $H$, namely $n^{1-H}$

The Effect of Topographic Factors on the Productivity of Mountain Grasslands in Northwestern Benin

The Atacora mountains range in northern Benin (660 m altitude) is a special ecosystem in the sudanian zone because of the overriding importance of topographic factors and shallow soils. The vegetation over this mountain range consists of shrub and tree savannas, woodlands and fallows. More and more cattle herds graze on this range. But the functioning of this ecosystem is still unknown like many others in the tropical zone (Sene & Zingari, 2001). This study aims to determine the impact of topography and mountain side exposure on the productivity of the Atacora mountains grasslands in the Atacora mountains

Unemployed Versus “Not in the Labor Force”: Is There a Difference?

This paper uses economic measures of behavior to examine the validity of the line drawn between individuals inside and outside the labor force, particularly between the unemployed and those outside the labor force. If labor force states are indistinguishable, the unemployment rate is open to interpretation. Our findings suggest that labor force statuses are distinct for mature adults and less distinct for teenagers. However, among mature adults, the degree of distinctiveness varies by race and ethnicity. Since 1990, there has been increased instability between the labor force statuses of the unemployed and those outside the labor force in some groups

On the prevalence of bridged macrocyclic pyrroloindolines formed in regiodivergent alkylations of tryptophan.

A Friedel-Crafts alkylation is described that efficiently transforms tryptophan-containing peptides into macrocycles of varying ring connectivity. Factors are surveyed that influence the distribution of regioisomers, with a focus on indole C3-alkylations leading to bridged endo-pyrroloindolines. We probe the stability and stereochemistry of these pyrroloindolines, study their rearrangement to C2-linked indolic macrocycles, and demonstrate a scalable, stereoselective synthesis of this compound class. Placing the macrocyclization in sequence with further template-initiated annulation leads to extraordinary polycyclic products and further demonstrates the potential for this chemistry to drive novel peptidomimetic lead discovery programs

Temperature-dependent preferences for advertisement-call frequency in females of Hyla versicolor

Abstract only availableMale treefrogs produce loud and persistent acoustic signals called advertisement calls to attract mates. Ectothermic animals like frogs face an interesting challenge, in that temperature can significantly impact characteristics of the species-specific advertisement call. The mate-choice preferences of female gray treefrogs (H. versicolor) have been extensively studied (reviewed by Gerhardt & Huber 2002). It has been found that females prefer calls with standard frequency peaks of 1.1 kHz + 2.2 kHz over calls with higher and lower frequencies at 20º C. However, it is not known how this preference is affected by temperature. To determine whether acoustic preferences based on frequency are temperature-dependent, I collected female frogs during their breeding season and tested them in a temperature-controlled anechoic testing chamber. I generated ten different computer-synthesized advertisement calls that ranged in frequency between 0.55 + 1.1 kHz to 1.5 + 3.0 kHz. In two-speaker choice tests conducted at three different temperatures (15º C, 20º C and 25º C), females "chose" (moved within 10 cm of a speaker) between a call with standard frequency peaks of 1.1 + 2.2 kHz and one of the nine alternative calls. Preliminary results indicate the preferred frequencies appeared to remain 1.1 + 2.2 kHz at lower temperatures. However, at higher temperatures, female frogs were more likely to approach high-frequency calls. These results will be discussed in the context of known temperature-dependent physiological processes in the inner ear of frogs.NIH grant to H.C. Gerhard

Policy measures and cyber insurance: a framework

The role of the insurance industry in driving improvements in cyber security has been identified as mutually beneficial for both insurers and policy-makers. To date, there has been no consideration of the roles governments and the insurance industry should pursue in support of this public–private partnership. This paper rectifies this omission and presents a framework to help underpin such a partnership, giving particular consideration to possible government interventions that might affect the cyber insurance market. We have undertaken a qualitative analysis of reports published by policy-making institutions and organisations working in the cyber insurance domain; we have also conducted interviews with cyber insurance professionals. Together, these constitute a stakeholder analysis upon which we build our framework. In addition, we present a research roadmap to demonstrate how the ideas described might be taken forward

The Peculiar Atmospheric Chemistry of KELT-9b

The atmospheric temperatures of the ultra-hot Jupiter KELT-9b straddle the transition between gas giants and stars, and therefore between two traditionally distinct regimes of atmospheric chemistry. Previous theoretical studies assume the atmosphere of KELT-9b to be in chemical equilibrium. Despite the high ultraviolet flux from KELT-9, we show using photochemical kinetics calculations that the observable atmosphere of KELT-9b is predicted to be close to chemical equilibrium, which greatly simplifies any theoretical interpretation of its spectra. It also makes the atmosphere of KELT-9b, which is expected to be cloudfree, a tightly constrained chemical system that lends itself to a clean set of theoretical predictions. Due to the lower pressures probed in transmission (compared to emission) spectroscopy, we predict the abundance of water to vary by several orders of magnitude across the atmospheric limb depending on temperature, which makes water a sensitive thermometer. Carbon monoxide is predicted to be the dominant molecule under a wide range of scenarios, rendering it a robust diagnostic of the metallicity when analyzed in tandem with water. All of the other usual suspects (acetylene, ammonia, carbon dioxide, hydrogen cyanide, methane) are predicted to be subdominant at solar metallicity, while atomic oxygen, iron and magnesium are predicted to have relative abundances as high as 1 part in 10,000. Neutral atomic iron is predicted to be seen through a forest of optical and near-infrared lines, which makes KELT-9b suitable for high-resolution ground-based spectroscopy with HARPS-N or CARMENES. We summarize future observational prospects of characterizing the atmosphere of KELT-9b.Comment: Accepted by ApJ. 9 pages, 6 figures. Corrected minor errors in Figures 1a and 1b (some line styles were switched by accident), text and conclusions unchanged, these minor changes will be updated in final ApJ proo