Public Willingness to Pay for Continuous and Probabilistic Hazard Information

Investments in new weather forecasting technologies and communication products can be costly and serve the ultimate purpose of protecting life and property. The Forecasting a Continuum of Environmental Threats (FACETs) paradigm attempts to improve technology and communication through the provision of probabilistic hazard information (PHI). The research and technology necessary to produce this information requires a substantial resource investment, but the societal value of the information may outweigh the costs. This study provides an initial estimate of this value by exploring public willingness to pay (WTP) for an app that provides continuously updated, geographically situated PHI that could be utilized during a tornado event. Findings indicate that the mean WTP, in a one-time payment, for this precise hazard information product is $7.53 per person. Aggregated to the US population, the estimated value is between$901 million and $1.56 billion. These findings indicate that federal agencies and private companies are likely to generate a substantial surplus by developing these products and will contribute to improving informed decision-making and protecting lives and property

Diagnosis, Management, and Investigational Therapies for Food Allergies

Food allergies have increased in prevalence over the past 20 years, now becoming an important public health concern. Although there are no therapies currently available for routine clinical care, recent reports have indicated that immunotherapies targeting the mucosal immune system may be effective. Oral immunotherapy is conducted by administering small, increasing amounts of food allergen; it has shown promise for desensitizing individuals with peanut, egg, or milk allergies. Sublingual immunotherapy also desensitizes allergic patients to foods—2 major studies have examined the effects of sublingual immunotherapy in subjects with peanut allergies. We review the complex nature of IgE-mediated food allergies and the therapies being evaluated in clinical trials. We focus on the diagnosis and management of food allergies and investigational therapies

Ultrafast dynamics in light-driven molecular rotary motors probed by femtosecond stimulated raman spectroscopy

Photochemical isomerization in sterically crowded chiral alkenes is the driving force for molecular rotary motors in nanoscale machines. Here the excited state dynamics and structural evolution of the prototypical light driven rotary motor are followed on the ultrafast timescale by femtosecond stimulated Raman spectroscopy (FSRS) and transient absorption (TA). TA reveals a sub 100 fs blue shift and decay of the Franck-Condon bright state arising from relaxation along the reactive potential energy surface. The decay is accompanied by coherently excited vibrational dynamics which survive the excited state structural evolution. The ultrafast Franck-Condon bright state relaxation is to a dark excited state, which FSRS reveals to have a rich spectrum compared to the electronic ground state, with the most intense Raman active modes shifted to significantly lower wavenumber. This is discussed in terms of a reduced bond order of the central bridging bond and overall weakening of bonds in the dark state, which is supported by electronic structure calculations. The observed evolution in the FSRS spectrum is assigned to vibrational cooling accompanied by partitioning of the dark state between the product isomer and the original ground state. Formation of the product isomer is observed in real time by FSRS. It is formed vibrationally hot and cools over several picoseconds, completing the characterization of the light driven half of the photocycle

Solid state synthesis of BiFeO3 occurs through the intermediate Bi25FeO39 compound

The solid-state synthesis of perovskite BiFeO3 has been a topic of interest for decades. Many studies have reported challenges in the synthesis of BiFeO3 from starting oxides of Bi2O3 and Fe2O3, mainly associated with the development of persistent secondary phases such as Bi25FeO39 (sillenite) and Bi2Fe4O9 (mullite). These secondary phases are thought to be a consequence of unreacted Fe-rich and Bi-rich regions, that is, incomplete interdiffusion. In the present work, in situ high-temperature X-ray diffraction is used to demonstrate that Bi2O3 first reacts with Fe2O3 to form sillenite Bi25FeO39, which then reacts with the remaining Fe2O3 to form BiFeO3. Therefore, the synthesis of perovskite BiFeO3 is shown to occur via a two-step reaction sequence with Bi25FeO39 as an intermediate compound. Because Bi25FeO39 and the γ-Bi2O3 phase are isostructural, it is difficult to discriminate them solely from X-ray diffraction. Evidence is presented for the existence of the intermediate sillenite Bi25FeO39 using quenching experiments, comparisons between Bi2O3 behavior by itself and in the presence of Fe2O3, and crystal structure examination. With this new information, a proposed reaction pathway from the starting oxides to the product is presented

Survival, Social Cohesion and Rock Art: The Painted Hands of Western Arnhem Land, Australia

This paper explores the complex story of a particular style of rock art in western Arnhem Land known as ‘Painted Hands’. Using new evidence from recent fieldwork, we present a definition for their style, distribution and place in the stylistic chronologies of this region. We argue these motifs played an important cultural role in Aboriginal society during the period of European settlement in the region. We explore the complex messages embedded in the design features of the Painted Hands, arguing that they are more than simply hand stencils or markers of individuality. We suggest that these figures represent stylized and intensely encoded motifs with the power to communicate a high level of personal, clan and ceremonial identity at a time when all aspects of Aboriginal cultural identity were under threat.Sally K. May, Luke Taylor, Catherine Frieman, Paul S.C. Taçon, Daryl Wesley, Tristen Jones, Joakim Goldhahn, Charlie Munguld

The modern pollen-vegetation relationship of a tropical forest-savannah mosaic landscape, Ghana, West Africa

Transitions between forest and savannah vegetation types in fossil pollen records are often poorly understood due to over-production by taxa such as Poaceae and a lack of modern pollen-vegetation studies. Here, modern pollen assemblages from within a forest-savannah transition in West Africa are presented and compared, their characteristic taxa discussed, and implications for the fossil record considered. Fifteen artificial pollen traps were deployed for 1 year, to collect pollen rain from three vegetation plots within the forest-savannah transition in Ghana. High percentages of Poaceae and Melastomataceae/Combretaceae were recorded in all three plots. Erythrophleum suaveolens characterised the forest plot, Manilkara obovata the transition plot and Terminalia the savannah plot. The results indicate that Poaceae pollen influx rates provide the best representation of the forest-savannah gradient, and that a Poaceae abundance of >40% should be considered as indicative of savannah-type vegetation in the fossil record