Evaporation induced flow inside circular wells

Flow field and height averaged radial velocity inside a droplet evaporating in an open circular well were calculated for different modes of liquid evaporation.Comment: 5 page, 3 figures, submitted to European Physical Journal

Correlation effects during liquid infiltration into hydrophobic nanoporous mediums

Correlation effects arising during liquid infiltration into hydrophobic porous medium are considered. On the basis of these effects a mechanism of energy absorption at filling porous medium by nonwetting liquid is suggested. In accordance with this mechanism, the absorption of mechanical energy is a result expenditure of energy for the formation of menisci in the pores on the shell of the infinite cluster and expenditure of energy for the formation of liquid-porous medium interface in the pores belonging to the infinite cluster of filled pores. It was found that in dependences on the porosity and, consequently, in dependences on the number of filled pores neighbors, the thermal effect of filling can be either positive or negative and the cycle of infiltration-defiltration can be closed with full outflow of liquid. It can occur under certain relation between percolation properties of porous medium and the energy characteristics of the liquid-porous medium interface and the liquid-gas interface. It is shown that a consecutive account of these correlation effects and percolation properties of the pores space during infiltration allow to describe all experimental data under discussion

Exploring variability in the diet of depredating sperm whales in the Gulf of Alaska through stable isotope analysis

Sperm whales interact with commercially important groundfish fisheries offshore in the Gulf of Alaska (GOA). This study aims to use stable isotope analysis to better understand the trophic variability of sperm whales and their potential prey, and to use dietary mixing models to estimate the importance of prey species to sperm whale diets. We analysed tissue samples from sperm whales and seven potential prey (five groundfish and two squid species). Samples were analysed for stable carbon and nitrogen isotope ratios, and diet composition was estimated using Bayesian isotopic mixing models. Mixing model results suggest that an isotopically combined sablefish/ dogfish group, skates and rockfish make up the largest proportion of sperm whale diets (35%, 28% and 12%) in the GOA. The top prey items of whales that interact more frequently with fishing vessels consisted of skates (49%) and the sablefish/dogfish group (24%). This is the first known study to provide an isotopic baseline of adult male sperm whales and these adult groundfish and offshore squid species, and to assign contributions of prey to whale diets in the GOA. This study provides information to commercial fishermen and fisheries managers to better understand trophic connections of important commercial species.Data were collected in collaboration with Cascadia Research Collective, Scripps Institution of Oceanography, Alaska Sea Life Center, Alaska Longline Fishermen’s Association and the Sitka Sound Science Center. SEASWAP co-PIs were all integral in making this project happen: Linda Behnken, Dan Falvey, Victoria O’Connell, Aaron Thode and Russ Andrews. John Calambokidis and Greg Schorr collected biopsy samples used in this project. Kelly Robertson and Gabriela Serra-Valente archived samples at Southwest Fisheries Science Center. Special thanks to the commercial longline fishermen who donated fish and squid that they caught: Frank Balovich and Cale Laduke (F/V Carole D), Paul Ipok (F/V Myra), Walt Cunningham and Jeff Farvour (F/V Christi-Rob), Ryan Nichols (F/V Nekton), Stephen Rhoads and Nick Nekeferof (F/V Magia), Phil Wyman and Kevin Johnson (F/V Archangel), Lucas Skordahl (F/V Tyee), Tyrus Moffitt and Alek Dyakanoff. NMFS GOA longline survey, bottom trawl survey and ecosystem assessment cruise personnel collected specimens: Chris Lunsford, Cindy Tribuzio, Pete Hulson, Dana Hanselman, Cheryl Barnes, Nancy Roberson, Jamal Moss and Wes Strasburger. Laboratory and analysis assistance provided by Illiana Ruiz-Cooley, Todd Miller, Casey Clark, John Logan, Andrew Parnell, Ellen Chenoweth, Madison Kosma, Mike Sigler, Corey Fugate, Matt Rogers, Kate Hauch, Michelle Parke, Kristina Long, Nevé Baker, Emily Whitney and Annie Masterman. Jen Cedarleaf archived historical samples and managed the database. The Inter-Library-Loan folks with the UAF Rasmussen library found all kinds of crazy whaling documents. Finally, special thanks to the Alaska Stable Isotope Facility team of MatWooller, Tim Howe and Norma Haubenstock for their work running bulk isotopes for all of these samples.Ye

Scrub typhus ecology: a systematic review of Orientia in vectors and hosts

Abstract Scrub typhus, caused by Orientia tsutsugamushi, is an important and neglected vector-borne zoonotic disease with an expanding known distribution. The ecology of the disease is complex and poorly understood, impairing discussion of public health interventions. To highlight what we know and the themes of our ignorance, we conducted a systematic review of all studies investigating the pathogen in vectors and non-human hosts. A total of 276 articles in 7 languages were included, with 793 study sites across 30 countries. There was no time restriction for article inclusion, with the oldest published in 1924. Seventy-six potential vector species and 234 vertebrate host species were tested, accounting for over one million trombiculid mites (‘chiggers’) and 83,000 vertebrates. The proportion of O. tsutsugamushi positivity was recorded for different categories of laboratory test and host species. Vector and host collection sites were geocoded and mapped. Ecological data associated with these sites were summarised. A further 145 articles encompassing general themes of scrub typhus ecology were reviewed. These topics range from the life-cycle to transmission, habitats, seasonality and human risks. Important gaps in our understanding are highlighted together with possible tools to begin to unravel these. Many of the data reported are highly variable and inconsistent and minimum data reporting standards are proposed. With more recent reports of human Orientia sp. infection in the Middle East and South America and enormous advances in research technology over recent decades, this comprehensive review provides a detailed summary of work investigating this pathogen in vectors and non-human hosts and updates current understanding of the complex ecology of scrub typhus. A better understanding of scrub typhus ecology has important relevance to ongoing research into improving diagnostics, developing vaccines and identifying useful public health interventions to reduce the burden of the disease.</jats:p

Adipose Tissue Serves as a Reservoir for Recrudescent Rickettsia prowazekii Infection in a Mouse Model

Brill-Zinsser disease, the relapsing form of epidemic typhus, typically occurs in a susceptible host years or decades after the primary infection; however, the mechanisms of reactivation and the cellular reservoir during latency are poorly understood. Herein we describe a murine model for Brill-Zinsser disease, and use PCR and cell culture to show transient rickettsemia in mice treated with dexamethasone >3 months after clinical recovery from the primary infection. Treatment of similarly infected mice with cyclosporine failed to produce recrudescent bacteremia. Therapy with doxycycline for the primary infection prevented recrudescent bacteremia in most of these mice following treatment with dexamethasone. Rickettsia prowazekii (the etiologic agent of epidemic typhus) was detected by PCR, cell culture, and immunostaining methods in murine adipose tissue, but not in liver, spleen, lung, or central nervous system tissues of mice 4 months after recovery from the primary infection. The lungs of dexamethasone-treated mice showed impaired expression of β-defensin transcripts that may be involved in the pathogenesis of pulmonary lesions. In vitro, R. prowazekii rickettsiae infected and replicated in the murine adipocyte cell line 3T3-L1. Collectively these data suggest a role for adipose tissue as a potential reservoir for dormant infections with R. prowazekii

Data Reduction and Error Analysis for the Physical Sciences

ABSTRACT Polycrystalline thin films (PTF) of p-WSe2, p-WS2, and p-MoSe2 have been prepared and characterized with respect to their photoelectrochemical properties, p-WS2 showed the highest open-circuit photovoltages and the highest conversion efficiencies in various redox couples. In addition, the band structure of all the films has been determined experimentally and compared to those reported for single crystals. Over the last two decades a great deal of interest has developed in the area of photoelectrochemistry, particularly in the application of photoelectrochemical systems to the problem of solar energy conversion and storage. The interest is to develop new energy sources to supplement and eventually replace fossil fuels. The first photoelectrochemical experiment was performed in 1839 by Becquerel (1), who demonstrated that a voltage and current are generated when a silver chloride electrode, immersed in an electrolytic solution and connected to a counterelectrode, is illuminated. Although the concept of a semiconductor did not exist at that time, it is now clear that the electrode which Becquerel used had semiconducting properties. In 1955, Brattain and Garett (2) used germanium as the first semiconductor electrode in photoelectrochemistry. Since then, the knowledge of semiconductors has grown steadily. Fujishima and Honda (3) were the first to point out the potential application of photoelectrochemical systems for solar energy conversion and storage. They demonstrated that the photo-oxidation of water to 02 was possible by utilizing an n-type semiconducting titanium dioxide photoanode. Since then, there has been a large and rapidly growing international interest in the study of photoelectrochemistry of semiconductors (4). The effective use of solar energy in photovoltaic or photoelectrochemical applications depends in part on the development of materials that can show high conversion efficiencies and long-term stability under operation. In ad-*Electrochemical Society Active Member. **Electrochemical Society Student Member. dition, the desirable materials should have a bandgap that closely matches the solar spectrum and be made of readily available and inexpensive materials. We have focused our attention on the transition metal dichalcogenides (e.g., WSe2, WS2, MoSe2, and others), also known as layered or d-d semiconductors. Tributsch&apos;s (5, 6) pioneering work on the use of these materials has stimulated intensive research in this area, and single Crystals of a number of materials have been studied extensively in both aqueous and nonaqueous solvents and in photovoltaic and photoelectrosynthetic cells. The advantages of using these materials are that they have bandgaps (1.1-1.6 eV) that closely match the solar spectrum and exhibit high conversion efficiencies as single crystals. In addition, they can achieve long-term stability due to the fact that the transitions are localized in the nonbonding d orbitals of the metal. These materials consist of metal dichalcogenide sandwiches (e.g., Se-W-Se) held together by van der Waals forces. The fact that there is strong covalent bonding within the layers, but only weak interactions between layers, makes these materials highly anisotropic in their properties. For example, the surface parallel to the C axis (IIC) is more conducting than the surface perpendicular to the C axis (• Therefore, edges and surface imperfections on the surface parallel to the C axis act as efficient recombination centers for photogenerated carriers or products (7