bluuebunny/crossref_metadata_2025 huggingface dataset:
INTRODUCING THE FIRST WORLD WATCH LIST FOR DOMESTIC ANIMAL DIVERSITY
Authors: oftus Ronan I.
Published: August 2011

The recently published World Watch List for Domestic Animal Diversity (WWL-DAD) provides the first comprehensive list of endangered livestock breeds worldwide (FAO/LTNEP 1993). This document will function as a global early warning system to help prevent the erosion of livestock genetic resources. Seven species are covered, namely ass, buffalo, cattle, goat, horse, pig and sheep. Within these species, breeds at risk are defined as critical (The Critical Breeds List) or endangered (The Endangered Breeds List) based on the number of breeding females. Although the statistics for these seven species are still incomplete at the time of going to press, over 390 breeds are already known to be at risk.
GENETIC IMPROVEMENT AND GERMPLASM CONSERVATION FOR QUALITY
Authors: Matassino D. , Moioli B.M.
Published: August 2011

Biological diversity is the main measure of genetic evolution; it links to the state of genetic polymorphism as influenced by envirornmental changes and modulates the speed of transferring genetic information. The authors concentrate in this note on the importance of the contribution of indigenous animal genetic resources when addressing the complex and economically most important problem of the intrinsic quality of products of animal origin, with special reference to regional/local specificity.
Genetics of disease resistance inBos tauruscattle
Authors: Morris C.A.
Published: August 2011

This review summarises evidence for genetic variation ofBos tauruscattle to diseases encountered under temperate conditions, including internal and external parasitism, susceptibility to mycotoxic diseases (tall fescue toxicosis, facial eczema, ryegrass staggers), mastitis, ketosis, pasture bloat, leukosis, tuberculosis, foot and mouth, brucellosis and BSE. Averaging mean heritability estimates reviewed from 8 diseases (weighted equally) gave a value of 0.21, indicating that measurable genetic variation for disease traits inBos tauruscattle is somewhat less than that for production traits, such as milk yield or body weight. Many estimates, however, have high standard errors, and there could be an upward bias resulting from non-reporting of zero or non-significant estimates.

Few single-trait selection experiments have been conducted to study the genetics of disease resistance traits in cattle. For the disease traits where selection is being applied extensively, index selection for improved disease resistance and increased production is more common than single-trait selection. Results from a long-term (25 year) divergent selection experiment with resistance/susceptibility to pasture bloat in cattle in New Zealand are reviewed. Four single-year experiments comparing progeny of ‘high’ versus ‘low’ sires for resistance to disease are also reviewed, one in Australia studying faecal nematode egg counts, one in the USA involving the mycotoxic disease, tall fescue toxicosis, a third in New Zealand involving the mycotoxic disease, facial eczema, and a fourth in the USA involvingBrucella abortus.
Red Iberoamericana sobre la conservación de la biodiversidad de los animales domésticos locales para el desarrollo rural sostenible (CYTED. XII-H)
Authors: Delgado J.V.
Published: August 2011

En este documento se presenta una red temática latinoamericana con financiación del Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED), dedicada a la conservación de los recursos genéticos de los animales domésticos, al estudio de los sistemas de explotación tradicionales, as í como las repercusiones sociales y ecológicas de estos recursos, además de la evaluación de sus posibilidades en el desarrollo rural sostenible de los países implicados.

En esta red participan mas de 140 investigadores de 16 equipos multidisciplinares ubicados en 9 países Latinoamericanos (México, Brasil, Bolivia, Argentina, Venezuela, Uruguay, Cuba, Portugal y España).

Se presentan los objetivos de la red y las actividades realizadas junto con las acciones planeadas para el futuro.
The role of Rare Breeds International as a global organization for the conservation of farm animal genetic resources
Authors: Alderson L. , Ramsey K.
Published: August 2011

Rare Breeds International (RBI) is the global non-governmental organization (NGO) concerned with the conservation of animal genetic resources (AnGR). It works in conjunction with FAO and with other organizations associated with livestock production. RBI members form a grassroots network that is rich in experience and knowledge of native breeds and affiliated national organizations maintain a valuable database of AnGR. Information is disseminated through major international conferences which are held at intervals of three years and through annual regional meetings. The cumulative expertise of the RBI membership facilitates a wide variety of projects, which range from policy interaction with governmental agencies to emergency rescue action and breeding programmes for relic breeds. RBI communicates mainly through publication of proceedings of major conferences and also by dedicated and linked websites.
Development of a Regional Focal Point for animal genetic resources: the European example
Authors: Planchenault D. , Ollivier L.
Published: August 2011

This paper describes the process that lead to the creation of the European Regional Focal Point (ERFP). The action was suggested by the FAO Global Strategy (1995) aimed to assist countries to stop animal diversity erosion by helping them with a better use and preservation of their livestock resources.

In 1997, France accepted the responsibility of developing an ERFP though its Bureau des Ressources Génétiques (BRG). During the first year, the ERFP held meaningful discussions with the different European countries with the objective of finding a general agreement for an organisational structure as well as a medium-term work programme. The following step was settled during the Annual Meeting of the European Association for Animal Production (EAAP) in Warsaw where it was agreed that the new body had to have a light structure and respect national sovereignty regarding the AnGR.

In February 2000, following a difficult internal debate involving the establishment of a basic strategy and further steps, an enquiry was launched among the National Coordinators in order to have an overall picture and to evaluate the usefulness of the proposed organisation to be established. In 2000 during the 6th Workshop of the European NCs, the ERFP was created.

The new structure is based on

a) an Annual Meeting of National Focal Points;

b) a Steering Committee; and

c) a Secretariat to be elected among the National Focal Points to serve for a limited period.
Conservation of livestock breed diversity
Authors: Barker J.S.F.
Published: August 2011

Mankind uses some 40 species of animals as domestic livestock to meet our needs for food, clothing, power, etc. Within these species, there are in total some 4,500 breeds that are referred to as the global animal genetic resources. Each breed comprises a unique set of genes. More than 30% of breeds are estimated to be at risk of extinction, and many more, particularly in developing countries, are threatened by inefficient utilization. The Food and Agriculture Organization of the United Nations has been mandated by its member nations to manage the global animal genetic resources, and major progress has been made in the last few years. However, resources are limited, and priorities will have to be set for breed conservation, for breed development programmes and for evaluation studies. Breeds that are taxonomically distinct should be favoured for conservation, the objective being to maintain maximum genetic diversity of each livestock species. Genetic distances and phylogenetic diversity provide the best available objective criterion, and microsatellites are the current markers of choice for obtaining the genetic data. Microsatellite-based genetic distances will describe breed similarities due to common ancestry, but cannot account for consequences of artificial or natural selection. Phylogenetic trees for 11 water buffalo populations in southeast Asia, constructed using 25 polymorphic protein coding loci or 21 microsatellite loci, show differences in both topology and branch lengths, but the microsatellite tree is a better representation of the similarities due to common ancestry. Thus phylogenetic diversity, based on microsatellite loci, should be used as an initial guide in making conservation decisions for livestock breeds.
The Early Carboniferous volcanic outliers of Little Cumbrae and south Bute: implications for westward attenuation of the Clyde Lava Plateau
Authors: Caldwell W. G. E. , Young G. M.
Published: August 2011

Little Cumbrae and south Bute are the closest outliers of Early Carboniferous Clyde Plateau volcanic rocks to those forming the plateau itself, and the only ones with the potential to reveal how the volcanic succession of the plateau becomes attenuated westward beneath the Firth of Clyde. Closest links are to the Renfrewshire Hills Block of the plateau proper, where the Clyde Plateau Volcanic Formation attains its greatest thickness and widest extent.

Basal lavas in both outliers can be correlated to the lower part of the Strathgryfe Member of the Clyde Plateau Volcanic Formation (Viséan, Holkerian), which rests disconformably on the Clyde Sandstone Formation (Tournaisian, Chadian). Relative to the Renfrewshire Hills Block, this implies intervening overlap of three older members of the Clyde Plateau Formation and overstep of a varied sedimentary foundation. Higher lavas and pyroclastic accumulations in south Bute are correlative to the Misty Law Trachytic Member and upper part of the Strathgryfe Member. Thin lavas that cap the Renfrewshire Hills Block on its eastern flank probably never accumulated as far west as the present Firth of Clyde.

Southwestward from the Renfrewshire Hills, the Clyde Plateau lavas lose about two thirds of their 1000-m thickness in 25–30 km – a rate of thinning that implies they may extend no farther than the Sound of Bute or northeastern Arran.
Lamprophyre dikes as tectonic markers of late orogenic transtension timing and kinematics: A case study from the Central Iberian Zone
Authors: Scarrow Jane H. , Molina José Francisco , Bea Fernando , Montero Pilar , Vaughan Alan P. M.
Published: August 2011

Variscan Central Iberian Zone lamprophyre dikes cut synorogenic to late orogenic peraluminous S‐type granitoids marking an important shift in regional tectonic regime from earlier, 350–290 Ma, extension‐related crustal melting to later, 265 Ma, transtension‐related mantle melting. The mean trend of the camptonite and bostonite dikes strikes ∼36° counterclockwise of the associated N‐S trending Menga–El Pico fault zone. This indicates emplacement under sinistral transtension, D4, that postdates the D1 compressional, D2 main extensional, and D3 compressional phases of Variscan deformation in the Iberian Massif and gives new insight into late orogenic geodynamic evolution of the region. The progression from extension to transtension ensued as transpression, common in many orogens related to oblique plate convergence, waned. In this context, steep, lithosphere‐scale, Riedel fractures permitted transport of early formed, small‐scale, hydrous, enriched potassic mantle melts to shallow depths. Formation and location of such crustal‐scale shear may be determined by underlying mantle heterogeneities that focus sites of melting resulting in structurally weak zones of lithosphere. So, the mantle heterogeneity localizes strain and acts as a nucleation point for newly developed steep strike‐slip faults which then act as conduits for magma with magmatism controlling faulting rather than being a result of it. Throughout the geological record late orogenic K‐rich magmatism is associated with strike‐slip movement showing that orogenic igneous rocks are tectonomagmatic markers of geodynamic evolution.
A New International Network for in Situ Soil Moisture Data
Authors: Dorigo Wouter , van Oevelen Peter , Wagner Wolfgang , Drusch Matthias , Mecklenburg Susanne , Robock Alan , Jackson Thomas
Published: August 2011

The International Soil Moisture Network (ISMN) is a new data‐hosting center where globally available ground‐based soil moisture measurements are collected, harmonized, and made available to users through a Web interface (http://www.ipf.tuwien.ac.at/insitu). As the first international initiative of its kind, the ISMN will play a crucial role in globally assessing the quality of soil moisture estimates from spaceborne microwave sensors and land surface models; in uncovering how the hydrological cycle integrates with land, the atmosphere, and the ocean; and in studying climate change. The ISMN is fully operational and currently hosts soil moisture data from more than 500 stations spanning 18 different networks. For scientific use, access to the data is free of charge.
Making Sense of the Water Resources That Will Be Available for Future use
Authors: Hossain Faisal , Niyogi Dev , Adegoke Jimmy , Kallos George , Pielke Roger
Published: August 2011

Societally and environmentally important resources can be separated into five major categories: water, food, energy, human health, and ecosystem function. These resources, however, are intimately interlinked. Water, for example, is required for each of the other four resources. Estimating availability of water resources, as well as other resources, requires an assessment of the threats they face.
Applying Spaceborne Gravity Measurements to Ocean Studies
Authors: Zlotnicki Victor , Stammer Detlef
Published: August 2011

“Gravity From Space” for Oceans, Land Ice, and Sea Level Rise; Hamburg, Germany, 29–30 September 2010; Twenty‐five scientists met at the University of Hamburg's KlimaCampus to discuss current analyses and future applications of spaceborne gravity measurements to studies of ocean circulation, cryospheric science, and sea level rise. The Challenging Minisatellite Payload (CHAMP), Gravity Recovery and Climate Experiment (GRACE), and Gravity Field and Steady‐State Ocean Circulation Explorer (GOCE) satellites, complemented with radar and laser altimeters, provide the necessary data. Spaceborne gravity measurements provide two important quantities for ocean circulation studies: (1) the time‐averaged geoid, which when subtracted from a time mean sea surface from radar altimetry yields the absolute surface dynamic topography and absolute surface geostrophic currents, and (2) time changes in ocean bottom pressure and total ocean mass. For sea level rise, the difference between the globally averaged trend from altimetry and that from GRACE is used to infer the top‐to‐bottom steric component (the component of sea level rise resulting from expansion of seawater due to temperature and salt), which is observable with data from the Argo system, a network of drifting probes that measure temperature up to 2000 meters in depth, and from expendable bathythermographs (XBT), temperature sensors deployed by ships.
Research Spotlight: The traveling rings of the North Brazil Current
Authors: Schultz Colin
Published: August 2011

The North Brazil Current (NBC) moves northward along the northeastern coast of Brazil. Drawing from the South Equatorial Current and the outflow of freshwater from the Amazon River, the NBC carries warm, nutrient‐rich water north of the equator. Up near the coast of French Guiana, part of the NBC makes a hard right, flowing east along the equator. Once in a while the turn is especially sharp and the current loops around, pinching off an independently traveling parcel of ocean water. This portion of current travels northwest with a clockwise rotation, moving through the ocean like a Frisbee™ travels through air. (Journal of Geophysical Research‐Oceans, doi:10.1029/2010JC006575, 2011)
Integrating Remote Sensing Data Into Geographic Information Systems
Authors: Farr Tom G. , Granger Stephanie , Kopp Steve
Published: August 2011

Bridging the Gap Between Remote Sensing and GIS; Redlands, California, 17–18 November 2010; Fifty remote sensing scientists and geographic information systems (GIS) experts attended a joint NASA–Environmental Science Research Institute (ESRI) workshop at the headquarters of ESRI. The purpose of the workshop was to bring together a diverse community of experts to explore benefits and barriers to the integration of remote sensing data into GIS. Remote sensing represents an ever‐expanding source of scientific data about our planet. Some individual NASA missions alone provide more than 1 terabyte of data per day. Remote sensing data can help solve problems in diverse applications, including disaster response, environmental planning, global change, insurance, and private investment. These data attain their greatest value when combined with other data from a variety of sources, yet this seemingly simple step is often very challenging.
Outstanding Student Paper Awards
Authors: Anonymous
Published: August 2011

The following members received Outstanding Student Paper Awards at the 2010 AGU Fall Meeting in San Francisco, Calif. Awards for other sections and focus groups will be announced in future issues of Eos.
Research Spotlight: Assessing phosphorus reduction efforts in the Everglades
Authors: Tretkoff Ernie
Published: August 2011

Years of agricultural and urban runoff have resulted in too much phosphorus in northern regions of the Florida Everglades. To deal with this problem, very large constructed wetlands, known as Stormwater Treatment Areas (STAs), have been built to strip phosphorus from runoff before the water enters protected Everglades areas. The more than $1 billion STA project currently relies on large areas (cells) of submerged aquatic vegetation (SAV) to absorb phosphorus as the final stage of treatment. To evaluate how well the treatment cells are functioning, as well as the potential lower limits of treatment, it is essential to have an accurate picture of the inflows, outflows, and background phosphorus levels. Juston and DeBusk made long‐term measurements in one of the SAV cells. They found that after total phosphorous levels in the cells reached about 15 micrograms per liter, no more phosphorus removal occurred. They also analyzed inflow and outflow data from the cell and inferred background phosphorus concentrations for eight additional SAV cells. Background concentrations averaged around 16 micrograms per liter. (Water Resources Research, doi:10.1029/2010WR009294, 2011)
Research Spotlight: Tree ring record chronicles major Mesoamerican droughts
Authors: Tretkoff Ernie
Published: August 2011

A new tree ring record chronicles major Mesoamerican droughts in the past millennium that may have contributed to the decline of some pre‐Hispanic civilizations. Although there is other evidence of droughts during the past millennium, the paleoclimate record had gaps. Stahle et al. used core samples from Montezuma bald cypress trees found in Barranca de Amealco, Querétaro, Mexico, to develop a 1238‐year tree ring chronology. They reconstructed the soil moisture record from the tree ring growth patterns. The new record provides the first dated, annually resolved climate record for Mexico and Central America spanning this time period.(Geophysical Research Letters, doi:10.1029/2010GL046472, 2011)
A New View of Coastal Oceans From the Space Station
Authors: Corson Michael R. , Davis Curtiss O.
Published: August 2011

Understanding and quantifying the natural processes that occur along coasts are critical components of managing environmental resources and planning and executing coastal operations, from humanitarian relief to military actions. However, the coastal ocean is complicated, with dissolved and suspended matter that hinders water transparency, phytoplankton blooms that can be toxic, and bathymetry and bottom types that vary over spatial scales of tens of meters, all of which affect processes in an area that spans millions of square kilometers. A hyperspectral imager collects the spectrum of the light received from each pixel in an image. For environmental characterization the wavelength range typically spans the visible and shortwave infrared wavelengths, and the spectrum is collected in contiguous spectral intervals 1–10 nanometers wide. This spectral information is exploited to provide significantly more information about vegetation, minerals, and other components in the scene than can be retrieved from panchromatic or even multispectral imagery, which rely primarily on the shape of the object for detection [Goetz et al., 1985]. Such technology can also work over shallow seas. Over the past 2 decades, experiments with hyperspectral imagers on airborne platforms have demonstrated the ability to characterize the coastal environment [Davis et al., 2002, Davis et al. 2006] and produce maps of coastal bathymetry, in‐water constituents, and bottom type.
Dynamos, Domains, and Paleomagnetic Poles
Authors: Kent Dennis , Pan Yongxin
Published: August 2011

Earth's and Planetary Interiors: Observation and Numerical Models of Paleomagnetic and Planetary Magnetism; Beijing, China, 7–11 July 2010; The second international Beijing Earth and Planetary Interior Symposium (BEPIS;http://www.paleomag.net/meeting) was held at the Institute of Geology and Geophysics, Chinese Academy of Sciences (CAS), just down the road from the Bird's Nest and other iconic structures of the 2008 Beijing Olympics. The symposium was organized by Rixiang Zhu (CAS, Beijing, China) and Keke Zhang (Exeter University, Exeter, UK) and brought together more than 100 scientists, including 30 graduate students from 10 countries. Thirty‐nine invited talks were organized along three major themes: planetary dynamos, paleomagnetism, and mineral magnetism. The talks were held in alternating and sometimes closely interleaved sessions and were supported by 40 poster presentations.
Research Spotlight: Variability of the East Greenland–Irminger Current
Authors: Tretkoff Ernie
Published: August 2011

The East Greenland–Irminger Current (EGIC), which flows southwestward along the eastern coast of Greenland, is important because its variability likely influences convection in the Labrador and Irminger seas and could affect the global meridional overturning circulation. Daniault et al. present new measurements of the EGIC transport variability from 1992 to 2009 based on satellite altimetry data and 2 years of data from a moored array. They found that the EGIC transport was close to average from 1992 to 1996, decreased between 1997 and 2005, and has increased since 2006. Beyond this decadal variability the researchers found no significant trend in the 1992–2009 EGIC transport time series, confirming that EGIC transport variability has not changed significantly over the past 2 decades. (Geophysical Research Letters, doi:10.1029/2011GL046863, 2011)
Economics and societal impacts of tornadoes
Authors: Bluestein Howard B.
Published: August 2011

During the spring of 2011, there were a record number of unusually strong and devastating tornadoes in the United States, which killed more than 500 people, the most in the country since 1953. Tornadoes are responsible for more than $1 billion annually (adjusted to 2007 U.S. dollars) in property damage and for disrupting thousands of lives and businesses. The most notable tornado this past spring devastated Joplin, Mo.; tornadoes also struck such diverse locations as Springfield, Mass.; Tuscaloosa, Ala.; Raleigh, N. C.; communities near Oklahoma City, Okla.; Minneapolis, Minn.; central and east Texas; Philadelphia, Pa.; and St. Louis, Mo. It is therefore timely to assess the economic and societal impacts of tornadoes. In this book the authors use various statistical techniques to evaluate the cost of tornadoes to society. They begin by reviewing the methodologies of formulating a tornado climatology across diverse regions according to tornado intensity, deaths, injuries, and property damage, and they then provide a history of the U.S. National Weather Service's (NWS) public warning efforts, describe tornado shelters and how the public responds to warnings, and suggest ways to reduce tornado risk.
Simulating observations of solar irradiance
Authors: Balcerak Ernie
Published: August 2011

Rising concentrations of carbon dioxide and other greenhouse gases in the atmosphere change how much solar radiation is reflected back into space. A proposed NASA mission, Climate Absolute Radiance and Refractivity Observatory (CLARREO), would make benchmark measurements of shortwave reflectance and longwave radiance spectra and of atmospheric refractivity to help researchers understand the changing solar reflectance and its effects on climate. To help mission planners and to determine the utility of solar reflectance data from CLARREO for understanding climate forcings and feedbacks,Feldman et al. introduce an observational system simulation experiment that calculates the signals of future climate forcings and feedbacks in top‐of‐atmosphere reflectance spectra. The simulation experiment allows mission planners to simulate CLARREO instrument measurements. They found that expected forcings from increases in anthropogenic emissions would be detectable and the proposed mission should help scientists understand climate forcings and feedbacks. (Journal of Geophysical Research‐Atmospheres, doi:10.1029/2010JD015350, 2011)
Infrared radiation in the thermosphere at the onset of solar cycle 24
Authors: Hunt Linda A. , Mlynczak Martin G. , Marshall B. Thomas , Mertens Christopher J. , Mast Jeffrey C. , Thompson R. Earl , Gordley Larry L. , Russell James M.
Published: August 2011

The effects of solar cycle 24 are now clearly evident in the infrared radiative cooling of the thermosphere as observed by the SABER instrument on the NASA TIMED satellite. After reaching a minimum in 2009, infrared radiative cooling of the thermosphere by nitric oxide (NO) and carbon dioxide (CO2) has been steadily increasing. The global infrared power radiated by NO in mid‐April 2011 is about four times the minimum value while the CO2 power is about 15% larger than at the minimum. In addition, the short‐term variability of the NO emission has increased and is strongly correlated with increased geomagnetic variability as inferred from the Ap index. The increasing levels of infrared emission are indicative of a warming thermosphere and possibly increasing levels of atomic oxygen and nitric oxide. However the infrared power presently radiated by NO is only about 40% of the maximum value observed by the SABER instrument in late 2002 while the CO2 power is now about 80% of the maximum observed value. The SABER infrared time series, now approaching 10 years in length, is a unique climate data record for testing the radiative and chemical physics of upper atmosphere general circulation models.
The Behavioral Development of Korean Children in Institutional Care and International Adoptive Families
Authors: Lee Richard M. , Seol Kyoung Ok , Sung Miyoung , Miller Matthew J. ,   The Minnesota International Adoption Project Team at University of Minnesota, Twin Cities Campus
Published: August 2011

In this study, the authors compared the behavioral development of 4- to 8-year-old South Korean children placed in institutional care ( n = 230) or adopted internationally ( n = 382), with age of entry, parental status, reason for institutionalization, and postinstitutionalization parental contact as risk factors for institutionalized children. There was a placement effect of adoption and support for age of entry and parental status as risk factors. Relinquished children institutionalized before age 2 fared the poorest across groups. Children institutionalized after age 2 with deceased/unknown parents fared best among institutionalized children. Institutionalization due to family disruption was a risk for relinquished children only, whereas parental contact did not increase the risk for behavioral problems. The unique sample population and other limitations are discussed.
Work/Family Demands, Work Flexibility, Work/Family Conflict, and Their Consequences at Work: A National Probability Sample in Taiwan
Authors: Lu Luo , Kao Shu-Fang , Chang Ting-Ting , Wu Hsin-Pei , Cooper Cary L.
Published: August 2011

The aim of this research was to explore relations between work/family demands, work flexibility, work/family conflict, and work-related outcomes in the cultural context of Chinese society, using a national probability sample. For Taiwanese employees, work demands were positively related to work/family conflict, whereas both work and family demands were positively related to family/work conflict. Work/family conflict was negatively related to job satisfaction and family/work conflict to organizational commitment. More importantly, the authors found that organizational policies and practices such as work flexibility could alleviate feelings of work interfering with family, further enhancing job satisfaction and organizational commitment. It is recommended that various family-friendly company policies be reformulated taking into account core cultural values such as individualism-collectivism.
Microsomal prostaglandin E synthase-1 exhibits one-third-of-the-sites reactivity
Authors: He Shan , Wu Yiran , Yu Daqi , Lai Luhua
Published: August 2011

mPGES-1 (microsomal prostaglandin E synthase-1) is a newly recognized target for the treatment of inflammatory diseases. As the terminal enzyme of the prostaglandin production pathway, mPGES-1 inhibition may have a low risk of side effects. Inhibitors of mPGES-1 have attracted considerable attention as next-generation anti-inflammatory drugs. However, as mPGES-1 is a membrane protein, its enzymatic mechanism remains to be disclosed fully. We used MD (molecular dynamics) simulations, mutation analysis, hybrid experiments and co-IP (co-immunoprecipitation) to investigate the conformation transitions of mPGES-1 during catalysis. mPGES-1 forms a homotrimer with three substrate-binding sites (pockets). In the MD simulation, only one substrate molecule could bind to one of the pockets and form the active complex, suggesting that the mPGES-1 trimer has only one pocket active at any given time. This one-third-of-the-sites reactivity enzyme mechanism was verified further by hybridization experiments and MD simulations. The results of the present study revealed for the first time a novel one-third-of-the-sites reactivity enzyme mechanism for mPGES-1, and the unique substrate-binding pocket in our model constituted an active conformation that was suitable for further enzymatic mechanism study and structural-based drug design against mPGES-1.
O-band excited state quantum dot bilayer lasers
Authors: Majid M. A. , Childs D.T.D. , Kennedy K. , Airey R. , Hogg R. A. , Clarke E. , Spencer P. , Murray R.
Published: August 2011

Bilayer InAs/GaAs quantum dot (QD) lasers operating in the excited state at wavelengths that span the O-band are demonstrated. The higher saturated gain and lower scattering time of the excited states of the ensemble of QDs offers the opportunity for fast direct-modulation lasers. We predict an increase in K-factor limited modulation bandwidth from QD lasers operating in the excited state due to a reduction in carrier transport and scattering times whilst maintaining high peak modal gain.
Elastic relaxation and correlation of local strain gradients with ferroelectric domains in (001) BiFeO3 nanostructures
Authors: Klug Jeffrey A. , Holt Martin V. , Premnath Ramesh Nath , Joshi-Imre Alexandra , Hong Seungbum , Katiyar Ram S. , Bedzyk Michael J. , Auciello Orlando
Published: August 2011

We report an elastic relaxation and increase in local strain variation correlated with ferroelectric domains within epitaxial BiFeO3 thin film nanostructures fabricated by combined electron-beam and focused ion-beam nanolithography. Nano-focused x-ray diffraction microscopy provided new insights into the relationship between film strain and ferroelectric domains in nanostructures, namely: (i) an out-of-plane (C-axis) elastic relaxation of as much as −1.8% Δc/c in a BFO film-based nanostructure relative to the planar film lattice constant; (ii) an out-of-plane rotation trending from the center towards all released edges of the nanostructure; and (iii) an increase of inter-domain strain variation within the nanostructure of approximately 10 times the inter-domain variation found within the planar film, correlated with ferroelectric domain boundaries as confirmed by piezoresponse-force microscopy. These results indicate that the release of in-plane BFO/SRO mismatch strain in a planar film is taken up by the local ferroelectric domain structure after patterning, resulting in greatly increased mechanical strain gradients within the structure.
Local atomic and electronic structures and ferroelectric properties of PbZr0.52Ti0.48O3: An x-ray absorption study
Authors: Ray S. C. , Hsueh H. C. , Wu C. H. , Pao C. W. , Asokan K. , Liu M. T. , Tsai H. M. , Chuang C. H. , Pong W. F. , Chiou J. W. , Tsai M.-H. , Lee J. M. , Jang L. Y. , Chen J. M. , Lee J. F.
Published: August 2011

This work investigates local atomic and electronic structures of PbZr0.52Ti0.48O3 (PZT) thin films with <001>, <101>, and <111> orientations using extended x-ray absorption fine structure (EXAFS) and x-ray absorption near-edge structure (XANES) spectroscopy with θ = 0° and 70° incident angles. The EXAFS result indicates that the <001>-oriented PZT film has a polarization dominantly along the c-axis, while both <101>- and <111>-oriented PZT films have a dominant in-ab-plane polarization. The hysteresis-loop measurements show that the <001>-oriented PZT film has a much larger coercive field than those of other two PZT films, which indicates that the double-well potential along the c-axis is much deeper than that in the ab-plane.
Fluctuating wall pressures measured beneath a supersonic turbulent boundary layer
Authors: Beresh Steven J. , Henfling John F. , Spillers Russell W. , Pruett Brian O. M.
Published: August 2011

Wind tunnel experiments up to Mach 3 have provided fluctuating wall-pressure spectra beneath a supersonic turbulent boundary layer to frequencies reaching 400 kHz by combining data from piezoresistive silicon pressure transducers effective at low- and mid-range frequencies and piezoelectric quartz sensors to detect high frequency events. Data were corrected for spatial attenuation at high frequencies and for wind-tunnel noise and vibration at low frequencies. The resulting power spectra revealed the ω−1 dependence for fluctuations within the logarithmic region of the boundary layer but are essentially flat at low frequency and do not exhibit the theorized ω2 dependence. When normalized by outer flow variables, a slight dependence upon the Reynolds number is detected, but Mach number is the dominant parameter. Normalization by inner flow variables is largely successful for the ω−1 region but does not apply for lower frequencies. A comparison of the pressure fluctuation intensities with 50 years of historical data shows their reported magnitude chiefly is a function of the frequency response of the sensors. The present corrected data yield results in excess of the bulk of the historical data, but uncorrected data are consistent with lower magnitudes, suggesting that much of the historical compressible database may be biased low.
Waste-recycling Monte Carlo with optimal estimates: Application to free energy calculations in alloys
Authors: Adjanor Gilles , Athènes Manuel , Rodgers Jocelyn M.
Published: August 2011

The estimator proposed recently by Delmas and Jourdain for waste-recycling Monte Carlo achieves variance reduction optimally with respect to a control variate that is evaluated directly using the simulation data. Here, the performance of this estimator is assessed numerically for free energy calculations in generic binary alloys and is compared to those of other estimators taken from the literature. A systematic investigation with varying simulation parameters of a simplified system, the anti-ferromagnetic Ising model, is first carried out in the transmutation ensemble using path-sampling. We observe numerically that (i) the variance of the Delmas-Jourdain estimator is indeed reduced compared to that of other estimators; and that (ii) the resulting reduction is close to the maximal possible one, despite the inaccuracy in the estimated control variate. More extensive path-sampling simulations involving an FeCr alloy system described by a many-body potential additionally show that (iii) gradual transmutations accommodate the atomic frustrations; thus, alleviating the numerical ergodicity issue present in numerous alloy systems and eventually enabling the determination of phase coexistence conditions.
Acoustic vibrations of a circular nanowire by considering the effect of surface
Authors: Huang Gan-Yun , Kang Yi-Lan
Published: August 2011

In this work, the acoustic vibrations of a circular nanowire have been studied on the basis of surface elasticity model, where both the surface elastic property and surface inertia effect are captured. The phonon dispersion and the resonant frequencies for specific vibration modes have been calculated. It has been found from the numerical results that both the surface elastic property and the surface inertia have much effect on the vibration behavior of the nanowire, though depending on the vibration modes. The low-frequency Raman shift has also been considered. The results reveal the surface effect is significant in nanowires, which may make it possible to use Raman scattering to determine the surface properties.
Mn-Cr intersite independent magnetic behavior and electronic structures of LaMn3Cr4O12: Study from first-principles
Authors: Lv Shuhui , Li Hongping , Liu Xiaojuan , Meng Jian
Published: August 2011

The magnetic and electronic structures of LaMn3Cr4O12 are investigated using the full-potential linearized augmented plane wave method within both the generalized gradient approximation (GGA) and GGA + U (electronic correlation) methods. The calculated results indicate that LaMn3Cr4O12 is an antiferromagnetic insulator. The magnetic ordering is demonstrated to be G-type within both Mn-site and Cr-site spins. However, there is no obvious magnetic coupling between Mn-site and Cr-site sublattices, which is verified by the separate distribution of their corresponding partial density of states. Moreover, the magnetic coupling constants of JCr-Cr and JMn-Mn are predicted to be − 5.0 (− 2.8) and − 0.83 (− 0.63) meV within GGA (GGA + U), respectively, consistent with the experimentally observed two independent Néel temperatures (TN1 and TN2). The calculated densities of states reveal the experimentally reported charge formula of LaMn3+3Cr3+4O12.
Effect of interface roughness on acoustic loss in tunable thin film bulk acoustic wave resonators
Authors: Vorobiev A. , Berge J. , Gevorgian S. , Löffler M. , Olsson E.
Published: August 2011

Tunable 5.2 GHz bulk acoustic wave resonators utilizing BaxSr1−xTiO3 ferroelectric films with similar intrinsic properties but different interface roughness are fabricated and characterized. Increase in roughness from 3.2 nm up to 6.9 nm results in reduction in Q-factor from 350 down to 150 due to extrinsic acoustic losses caused by wave scattering at reflections from rough interfaces and other mechanisms associated with roughness. The increased roughness is a result of distortion of Pt bottom electrode caused by formation of heterogeneous enclosures of TiO2−x in the Pt layer.
Nonrelativistic Chern-Simons vortices on the torus
Authors: Akerblom N. , Cornelissen G. , Stavenga G. , van Holten J. W.
Published: August 2011

A classification of all periodic self-dual static vortex solutions of the Jackiw-Pi model is given. Physically acceptable solutions of the Liouville equation are related to a class of functions, which we term Ω-quasi-elliptic. This class includes, in particular, the elliptic functions and also contains a function previously investigated by Olesen. Some examples of solutions are studied numerically and we point out a peculiar phenomenon of lost vortex charge in the limit where the period lengths tend to infinity, that is, in the planar limit.
Dynamic superparamagnetism in cobalt doped Sm2O3 thin films
Authors: Gray Nathan W. , Tiwari Ashutosh
Published: August 2011

We report on the magnetic properties of insulating Sm1.9Co0.1O3 films grown on a SrTiO3 substrate. A pulsed laser deposition technique was used to grow the films under varied oxygen pressure. The films were characterized using several techniques, including x-ray diffraction, high-resolution transmission electron microscopy, and magnetic property measurements. Films prepared at lower oxygen pressures were found to be monoclinic, whereas the films prepared at high oxygen pressures were cubic. Both film phases exhibited superparamagnetic-like responses, with the monoclinic films showing a very high coercive field at low temperatures. Careful microstructural analysis showed no secondary phases or compositional variation that could account for the observed magnetic response. A model, based on the widely accepted bound polaron theory for insulating ferromagnets, is proposed to explain the magnetic behavior of Co doped Sm2O3 films. In this model, exchange mediating defects form magnetically active regions that behave like superparamagnetic clusters; however, unlike in superparamagnetic systems, the size of magnetically active regions is not static but changes dynamically with temperature.
Size-dependent resistivity and thermopower of nanocrystalline copper
Authors: Okram Gunadhor S. , Kaurav Netram
Published: August 2011

Nanocrystalline copper (NC-Cu) of average particle size (D) ranging from 29 to 55 nm was prepared using the polyol method. The compacted pellets of these nanoparticles were investigated using electrical resistivity (ρn) and thermopower (Sn) measurements in the temperature range from 5 to 300 K. The observed electrical resistivity and thermopower data for all the samples are typical of a good metal and the ρn(T) data are analyzed in the framework of the Bloch-Grüneisen theory. Our analysis indicates systematic departure from the bulk property for NC-Cu samples, decreasing effective Debye temperature, exponential decay of both the residual resistivity ratio (RRR) and the temperature coefficient of resistivity [α = (1/ρ)dρ/dT] as D decreases, yet the Boltzmann theory of electron transport still holds true (kFl ≫ 1). Further, the validity of the Nordheim-Gorter rule is also discussed. The temperature dependence of Sn is found to be quite sensitive as compared to bulk thermopower SBulk behavior, revealing the evolution of Sn and exhibiting a significant enhancement of the phonon drag peak as D decreases. The present findings overall suggest the significant influence of the grain boundaries, surface atoms, and phonon confinement.
Electrically-driven metal-insulator transition with tunable threshold voltage in a VO2-SmNiO3 heterostructure on silicon
Authors: Ha Sieu D. , Aydogdu Gulgun H. , Viswanath B. , Ramanathan Shriram
Published: August 2011

We fabricate a heterostructure of SmNiO3 and VO2 on silicon wherein both correlated oxides undergo a metal-insulator transition at different threshold temperatures. It is demonstrated that the threshold voltage for electrically switching the VO2 from insulating to metallic can be tuned depending on the conducting state of the SmNiO3 layer. An electrically triggered SmNiO3 phase transition induces a resistance modification in the layer, which alters the field distribution and shifts the effective threshold voltage for VO2 switching in a non-volatile manner. The ability to tune the switching characteristics in such heterostructures could be relevant for emerging correlated oxide adaptive electron devices.
Electrical transport properties of graphene on SiO2 with specific surface structures
Authors: Nagashio K. , Yamashita T. , Nishimura T. , Kita K. , Toriumi A.
Published: August 2011

The mobility of graphene transferred on a SiO2/Si substrate is limited to ∼10 000 cm2V−1s−1. Without understanding the graphene/SiO2 interaction, it is difficult to improve the electrical transport properties. Although surface structures on SiO2 such as silanol and siloxane groups are recognized, the relation between the surface treatment of SiO2 and graphene characteristics has not yet been elucidated. This paper discusses the electrical transport properties of graphene on specific surface structures of SiO2 prepared by O2-plasma treatments and reoxidization.
4,4′-, 5,5′-, and 6,6′-dimethyl-2,2′-bipyridyls: The structures, phase transitions, vibrations, and methyl group tunneling of their complexes with chloranilic acid
Authors: Bator G. , Sawka-Dobrowolska W. , Sobczyk L. , Grech E. , Nowicka-Scheibe J. , Pawlukojć A. , Wuttke J. , Baran J. , Owczarek M.
Published: August 2011

The crystal and molecular structures of 4,4′- and 6,6′-dimethyl-2,2′-bipyridyl complexes with 2,5-dichloro-3,6-dihydroxy-p-benzoquinone (chloranilic acid, CLA) have been determined and compared with those of the complex with the 5,5′-derivative, which is known to possess interesting antiferroelectric properties. In the crystalline state, all three compounds form hydrogen bonded chains with N+–H···O− and O–H···N bridges on both sides of the bipyridyl constituent. The comparison of three derivatives indicates that the N+–H···O− hydrogen bonds are shortest for the 5,5′-dimethyl complex. The 4,4′- and 6,6′-derivatives do not show any ferroelectric feature. The 6,6′-one is, however, characterized by a continuous phase transition, revealed in the differential scanning calorimetry, dilatometric, and dielectric characteristics. The tunneling splitting measured by neutron backscattering in the energy range ±30 μeV for the neat dimethyl bipyridyls and their complexes with CLA indicates that the different splittings are primarily due to the crystal packing effect and that charge transfer between interacting compounds plays only a minor role.
Generic relation between the electron work function and Young's modulus of metals
Authors: Hua Guomin , Li Dongyang
Published: August 2011

In this study, efforts were made to establish a generic relation between the Young’s modulus and the electron work function of polycrystalline metals, in which Young’s Modulus was defined as the second order derivative of interaction potential with respect to the equilibrium distance. The obtained Young’s modulus shows a sextic relation with the work function. Data of Young’s modulus and work function of polycrystalline metals, including Alkali earth metals, transition metals, and rare earth metals, can be fitted reasonably well by this derived generic relationship.
Conformation of a flexible chain in explicit solvent: Exact solvation potentials for short Lennard-Jones chains
Authors: Taylor Mark P. , Adhikari Shishir R.
Published: August 2011

The average conformation of a flexible chain molecule in solution is coupled to the local solvent structure. In a dense solvent, local chain structure often mirrors the pure solvent structure, whereas, in a dilute solvent, the chain can strongly perturb the solvent structure which, in turn, can lead to either chain expansion or compression. Here we use Monte Carlo (MC) simulation to study such solvent effects for a short Lennard-Lones (LJ) chain in monomeric LJ solvent. For an n-site chain molecule in solution these many-body solvent effects can be formally mapped to an n-body solvation potential. We have previously shown that for hard-sphere and square-well chain-in-solvent systems this n-body potential can be decomposed into a set of two-body potentials. Here, we show that this decomposition is also valid for the LJ system. Starting from high precision MC results for the n = 5 LJ chain-in-solvent system, we use a Boltzmann inversion technique to compute numerically exact sets of two-body solvation potentials which map the many-body chain-in-solvent problem to a few-body single-chain problem. We have carried out this mapping across the full solvent phase diagram including the dilute vapor, dense liquid, and supercritical regions and find that these sets of solvation potentials are able to encode the complete range of solvent effects found in the LJ chain-in-solvent system. We also show that these two-site solvation potentials can be used to obtain accurate multi-site intramolecular distribution functions and we discuss the application of these exact short chain potentials to the study of longer chains in solvent.