bluuebunny/crossref_metadata_2025 huggingface dataset:
Road to Extermination in Uganda
Authors: Edroma Eric L.
Published: April 2009

Uganda's national parks are littered with elephant carcasses, poachers' camps and meat-drying racks, and poachers are better armed and equipped than the guards. And the slaughter continues. Dr Edroma, who is Director of the Uganda Institute of Ecology, lists the steps that must be taken if the present disastrous situation is not to deteriorate to the point where Uganda's wildlife is effectively exterminated.
Last Chance for the California Condor?
Authors: Mills Stephen
Published: April 2009

With a wild population of only thirteen known birds, the California condor is close to extinction. In 1980 only two pairs even attempted to breed. Breeding in captivity seems the only hope of saving the species, but the project approved by the Federal Government has roused considerable controversy. The author, who spent two years in California, presents the arguments on both sides, outlines the reasons why he believes the experiment should be tried and assesses its chances of success. On June 30, however, after this article was written, a two-month-old California condor chick died while being handled. In a postscript to the article Stephen Mills comments on the effects of this death on the programme.
Saving Paraguay's Wilderness
Authors: Verschuren Jacques
Published: April 2009

Paraguay still has a vast area of almost undisturbed forest and savanna in the region known as the Chaco, where three large national parks, totalling over 1½ million hectares, protect a fauna that includes jaguar, puma, ocelot and a peccary that was ‘rediscovered’ in 1975. In 1979 the author, who is widely known as a scientist and conservationist, spent two months in Paraguay investigating the wildlife situation and national parks and has made recommendations for conservation measures to the Government.
A Visit to the Manu
Authors: Bassett Terence H. , de Macedo-Ruiz Hernando
Published: April 2009

To reach the Manu National Park means a day's journey by road over the Andes from Cusco, climbing up to the high puna grassland where one enters the park at the Tres Cruces guard post, 3300m above sea level. The last part of the road down to Shintuya at 300m has four unbridged river crossings that are impassable in the wet season from November to March. At Shintuya, if no park boat is available, the onward journey to Pakitsa, the administrative headquarters where there is accommodation, can only be made by hiring the Dominican Mission boat at $100 a day plus 30 gallons of gasoline (if you can get it) as well as enough for the return journey from Pakitsa to Cashu Cocha.
Rare Brazilian Sideneck Turtle
Authors: Mittermeier R.A. , Rhodin A.G.J. , da Rocha e Silva R. , de Oliveira N. Araujo
Published: April 2009

In 1976 one of the authors saw a pet turtle which he recognised to be Phrynops hogei. This was remarkable because hitherto the type specimen, first described in 1967, was the only one known to scientists. However, since 1976 three other live animals have been seen, and also eight museum specimens. From the new information the authors conclude that the range of the species is small, and also that the type locality was wrongly given. They think the turtle may well be endangered, and suggest a captive breeding programme for its conservation.
Will the Kafue Lechwe Survive the Kafue Dams?
Authors: Schuster Richard
Published: April 2009

In the early 1970s the huge lechwe herds gave the Kafue Flats in Zambia one of the highest carrying capacities in the world – an estimated 11,000kg per sq km. But these highly specialised antelopes depend on the annual floods of the Kafue river, to which particularly they have adapted their breeding behaviour and the leks in which they mate. Since the completion of two huge dams on the Kafue these floods are now controlled in the interests of making electricity, and not of the lechwe. The author, who studied the lechwe's social organisation and behaviour in the Lochinvar National Park, first describes the lechwe's remarkable lek system, how they are adapted to the floods to the point of being able to graze in water up to their shoulders, and the remarkable way in which they maximise the resources of the Flats. In the second part (page 481) he shows how the new flood control can disrupt their breeding behaviour and social organisation, which might lead to the extinction of the Kafue lechwe.
Israel restores Asiatic wild ass
Authors: clark Bill
Published: April 2009

In April 1982 Israeli conservationists released a test herd of Asiatic wild ass Equus hemionus into the central Negev Desert basin of Makhtesh Ramon as the first step in restoring this species into the wild. The five males are being closely monitored to determine how well they adjust to their freedom and if no serious problems are encountered they will be joined by females.
Rodrigues: can its flora be saved?
Authors: Strahm Wendy
Published: April 2009

Rodrigues, the smallest of the three Mascarene islands, is in immediate danger of losing most of its native vegetation due to the activities of man and introduced cattle and goats. The endemic fauna has mostly disappeared, leaving two endangered land birds and a fruit bat, and most of the plants may soon follow: seven native species are known only from five or fewer individuals. The author visited Rodrigues for two weeks in June and July 1982 with the Director of the Conservatoire Botanique of Stangalarch, Brest, France, in an effort to locate and propagate many of the rare species.
Galapagos conservation and tourism — 11 years on
Authors: Tindle R. W.
Published: April 2009

The author has been resident scientist and naturalist guide in the Galapagos Islands during 1970–72 and 1976–79, and throughout has been associated with sea-bird conservation in the archipelago. In July 1982, he visited the islands once again, and here reports on the effect of tourism on Galapagos wildlife over the 11-year period. Some of this work has be aided by the ffPS 100% Fund.
Can translocation help wild primates?
Authors: Caldecott Julian , Kavanagh Michael
Published: April 2009

Releasing animals into the wild, especially when they have become extinct there, is an appealing and dramatic conservation technique. It is, however, fraught with risks and often expensive; its success depends upon meticulous planning. The authors discuss the reasons for translocation, the many problems involved and the special cases where such an exercise may be justified.
Construction of a membrane-lytic immunotoxin using melittin and epidermal growth factor
Authors: Mei-Ling Chen , Dong Niu , Hui Ruan , Bing-Qing Pan , Jin-Ling Wang , De Wu , Jia-Jia Zhang , Qi-He Chen , Guo-Qing He
Published: April 2009

Epidermal growth factor receptor (EGFR) is becoming a perfect target for killing carcinoma cells, especially because of its overexpression on the surface of these cells. Cationic antimicrobial peptides (CAP) have their own special mechanism of membrane-lytic cytotoxicity. In this study, a membrane-lytic immunotoxin (IT), chimeric protein MEGFMEL, was constructed to kill carcinoma cells with EGFR overexpression. This protein is composed of mouse (Mus musculus) epidermal growth factor (MEGF), as the target part, and melittin (MEL), as the cytotoxic part. Using Escherichia coli BL21 and pET30a as expression strain and vector, respectively, 63.45 μg/ml of MEGFMEL (68% purity) was obtained through low-temperature induction of expression and a thawing-freezing purification procedure (without cytolysis). In vitro activity measurement showed that this MEGFMEL significantly induced a lethal effect on A431 carcinoma cells overexpressing EGFR on the surface, with an LD50 value 52.6 μg/ml. The results suggest that the use of CAP as the toxin in the construction of unique membrane-lytic ITs aimed at EGFR is feasible.
Construction and utilization of plant expression vectors withPMIgene as selection marker to recover transgenic plants ofCitrus sinensisL. Osbeck
Authors: Li-Hui Zeng , Hai-Feng Xu , Hui-Quang Wang , Shao-Hua Wu , Yi-Xuan Zhu
Published: April 2009

The plant expression vectors pCAMBIA1301PMIand pBIPMIwere constructed by substituting theEscherichia coliphosphomannose-isomerase (PMI) gene for thehptgene of pCAMBIA1301 andgusgene of pBI121, respectively. Epicotyl explants of the Xuegan sweet orange (Citrus sinensisL. Osbeck) were inoculated withAgrobacterium tumefaciensEHA105- pCAMBIA1301PMIand EHA105-pBIPMIand subsequently selected in a medium supplemented with a combination of 25 g/l mannose and 5 g/l sucrose as the carbon source. The transformation efficiency rate was 27.7% when transformed by pCAMBIA1301PMIand 12.7% by pBIPMI. Genetic transformation was confirmed by chlorophenol red assay and polymerase chain reaction (PCR). A new method for obtaining transgenic Xuegan sweet orange plants was developed using thePMI/mannose selection system.
Modeling the entry and trapping of solar energetic particles in the magnetosphere during the November 24–25, 2001 storm
Authors: Richard R. L. , El‐Alaoui M. , Ashour‐Abdalla M. , Walker R. J.
Published: April 2009

We have modeled the entry of solar energetic particles (SEPs) into the magnetosphere during the November 24–25, 2001 magnetic storm and the trapping of particles in the inner magnetosphere. The study used the technique of following many test particles, protons with energies greater than about 100 keV, in the electric and magnetic fields from a global magnetohydrodynamic (MHD) simulation of the magnetosphere during this storm. SEP protons formed a quasi‐trapped and trapped population near and within geosynchronous orbit. Preliminary data comparisons show that the simulation does a reasonably good job of predicting the differential flux measured by geosynchronous spacecraft. Particle trapping took place mainly as a result of particles becoming non‐adiabatic and crossing onto closed field lines. Particle flux in the inner magnetosphere increased dramatically as an interplanetary shock impacted and compressed the magnetosphere near 0600 UT, but long term trapping (hours) did not become widespread until about an hour later, during a further compression of the magnetosphere. Trapped and quasi‐trapped particles were lost during the simulation by motion through the magnetopause and by precipitation, primarily the former. This caused the particle population near and within geosynchronous orbit to gradually decrease later on during the latter part of the interval.
Pore‐scale and continuum modeling of gas flow pattern obtained by high‐resolution optical bench‐scale experiments
Authors: Geistlinger Helmut , Lazik Detlef , Krauss Gunnar , Vogel Hans‐Jörg
Published: April 2009

High‐resolution optical bench‐scale experiments were conducted in order to investigate local gas flow pattern and integral flow properties caused by point‐like gas injection into water‐saturated glass beads. The main goal of this study was to test the validity of the continuum approach for two‐fluid flow in macroscopic homogeneous media. Analyzing the steady state experimental gas flow pattern that satisfies the necessary coherence condition by image processing and calibrating the optical gas distribution by the gravimetrical gas saturation, it was found that a pulse‐like function yields the best fit for the lateral gas saturation profile. This strange behavior of a relatively sharp saturation transition is in contradiction to the widely anticipated picture of a smooth Gaussian‐like transition, which is obtained by the continuum approach. This transition is caused by the channelized flow structure, and it turns out that only a narrow range of capillary pressure is realized by the system, whereas the continuum approach assumes that within the representative elementary volume the whole spectrum of capillary pressures can be realized. It was found that the stochastical hypothesis proposed by Selker et al. (2007) that bridges pore scale and continuum scale is supported by the experiments. In order to study channelized gas flow on the pore scale, a variational treatment, which minimizes the free energy of an undulating capillary, was carried out. On the basis of thermodynamical arguments the geometric form of a microcapillary, macrochannel formation and a length‐scale‐dependent transition in gas flow pattern from coherent to incoherent flow are discussed.
An evaluation of the impacts of energy tree plantations on water resources in the United Kingdom under present and future UKCIP02 climate scenarios
Authors: Calder Ian R. , Nisbet Tom , Harrison Jennifer A.
Published: April 2009

The Hydrological Land Use Change model was used to assess the range of water resource impacts associated with four potential energy tree species (Eucalyptus nitens, Eucalyptus gunnii, Nothofagus sp., and Fraxinus excelsior) at eight United Kingdom locations under present and future, Environment Agency Rainfall and Weather Impacts Generator, climate scenarios generated using UK Climate Impacts Programme 2002 (UKCIP02). Parameter values were derived using expert opinion and interpolation because of limited data. For Fraxinus excelsior, there are questions concerning the unusual, in a world context, published findings that evaporation from a tree crop is less than that from grass. Model predictions indicated that under the present climate all tree species, excepting Fraxinus excelsior, at all sites have greater mean annual evaporation, (8 to 84%) and reduced water yields (−6 to −97%) compared with grass. The predicted increase in tree evaporation arises from parameter values reflecting both increased rainfall interception and higher transpiration due to deeper rooting depths. Under future climate scenarios, (1) “potential annual yield” (difference between actual rainfall and potential evaporation) will decrease, becoming negative at all studied sites in England and Wales by 2080; (2) at drier sites and for species with highest evaporation rates, E. nitens and Nothofagus, evaporation rates will decrease; (3) at wetter sites and for all species, evaporation rates will increase; (4) at all sites and for all species, water yields will decrease; (5) differences between species remain the same, with evaporation rates increasing and water yield decreasing in the order Fraxinus excelsior, grass, E. gunnii, Nothofagus, and E. Nitens; and (6) there is an overall trend through time toward convergence in water yields from trees and grass. If higher water yield predictions for Fraxinus excelsior are proved correct, this would represent an attractive land use option for water and energy production. Field research is required to validate these predictions. Assuming future climate changes match those predicted, soil moisture deficits will occur for longer periods during the year and will become increasingly limiting for evaporation. The monitoring of soil moisture may then provide one of the most sensitive methods of both determining model parameter values and testing predictions of differences in evaporation between species and changes in evaporation over time.
Mantle source variations beneath the Eastern Lau Spreading Center and the nature of subduction components in the Lau basin–Tonga arc system
Authors: Escrig S. , Bézos A. , Goldstein S. L. , Langmuir C. H. , Michael P. J.
Published: April 2009

New high‐density sampling of the Eastern Lau Spreading Center provides constraints on the processes that affect the mantle wedge beneath a back‐arc environment, including the effect of the subduction input on basalt petrogenesis and the change in subduction input with distance from the Tonga arc. We obtained trace element and Pb‐Sr‐Nd isotopic compositions of 64 samples distributed between 20.2°S and 22.3°S with an average spacing of ∼3.6 km. The trace element and isotope variations do not vary simply with distance from the arc and reflect variations in the mantle wedge composition and the presence of multiple components in the subduction input. The mantle wedge composition varies form north to south, owing to the southward migration of Indian‐like mantle, progressively replacing the initially Pacific‐like mantle wedge. The mantle wedge compositions also require an enriched mid‐ocean ridge basalt–like trace element enrichment that has little effect on isotope ratios, suggesting recent low‐degree melt enrichment events. The composition of the subduction input added to the mantle wedge is geographically variable and mirrors the changes observed in the Tonga arc island lavas. The combination of the back‐arc and arc data allows identification of several components contributing to the subduction input. These are a fluid derived from the altered oceanic crust with a possible sedimentary contribution, a pelagic sediment partial melt, and, in the southern Lau basin, a volcaniclastic sediment partial melt. While on a regional scale, there is a rough decrease in subduction influence with the distance from the arc, on smaller scales, the distribution of the subduction input reflects different mechanisms of the addition of the subduction input to a variable mantle wedge.
Decadal increases of anthropogenic CO2 along 149°E in the western North Pacific
Authors: Murata Akihiko , Kumamoto Yuichiro , Sasaki Ken‐ichi , Watanabe Shuichi , Fukasawa Masao
Published: April 2009

Using high‐quality data for dissolved inorganic carbon and the related water properties obtained by two cruises over 12 years (1993–2005), we estimated increases in anthropogenic CO2 (ΔnCTCAL) along the 149°E meridian (WHP P10) from 4°S to 30°N. Significant ΔnCTCAL was found down to a maximum depth of about 800 m. In the upper thermocline (25.0–26.0σθ), ΔnCTCAL was mostly 10–13 μmol kg−1, close to the value expected from recent increases in atmospheric CO2. In the lower thermocline (26.1–27.5σθ), ΔnCTCAL was 3.5 ± 0.9 and 4.7 ± 1.7 μmol kg−1 in North Pacific Intermediate Water and Antarctic Intermediate Water, respectively. Water column inventories of ΔnCTCAL over the 12 years were calculated to be 3.8 ± 1.2 mol m−2 (minimum) and 7.3 ± 2.2 mol m−2 (maximum) at latitudes 0°–10°N and 24°N–30°N, respectively, showing a distribution pattern similar to that of the long‐term anthropogenic CO2 accumulation reported previously. The uptake rate of anthropogenic CO2 along the WHP P10 line over the time period was estimated to be 0.5 ± 0.1 mol m−2 a−1, which is half the rate in the South Pacific (1.0 ± 0.4 mol m−2 a−1), but equal to that in the South Atlantic (0.6 ± 0.1 mol m−2 a−1). We discuss the relationships between ΔnCTCAL and changes in apparent oxygen utilization from the standpoint of physical‐biological interactions.
Radiative and turbulent surface heat fluxes over sea ice in the western Weddell Sea in early summer
Authors: Vihma Timo , Johansson Milla M. , Launiainen Jouko
Published: April 2009

The radiative and turbulent heat fluxes between the snow‐covered sea ice and the atmosphere were analyzed on the basis of observations during the Ice Station Polarstern (ISPOL) in the western Weddell Sea from 28 November 2004 to 2 January 2005. The net heat flux to the snowpack was 3 ± 2 W m−2 (mean ± standard deviation; defined positive toward snow), consisting of the net shortwave radiation (52 ± 8 W m−2), net longwave radiation (−29 ± 4 W m−2), latent heat flux (−14 ± 5 W m−2), and sensible heat flux (−6 ± 5 W m−2). The snowpack receives heat at daytime while releases heat every night. Snow thinning was due to approximately equal contributions of the increase of snow density, melt, and evaporation. The surface albedo only decreased from 0.9 to 0.8. During a case of cold air advection, the sensible heat flux was even below −50 W m−2. At night, the snow surface temperature was strongly controlled by the incoming longwave radiation. The diurnal cycle in the downward solar radiation drove diurnal cycles in 14 other variables. Comparisons against observations from the Arctic sea ice in summer indicated that at ISPOL the air was colder, surface albedo was higher, and a larger portion of the absorbed solar radiation was returned to the atmosphere via turbulent heat fluxes. The limited melt allowed larger diurnal cycles. Due to regional differences in atmospheric circulation and ice conditions, the ISPOL results cannot be fully generalized for the entire Antarctic sea ice zone.
Response of lower trophic level production to long‐term climate change in the southeastern Bering Sea
Authors: Jin Meibing , Deal Clara , Wang Jia , McRoy C. Peter
Published: April 2009

The Bering Sea ecosystem has undergone profound changes in response to climate regime shifts in the past decades. Here, lower trophic level production is assessed with a vertically one‐dimensional (1‐D) coupled ice‐ocean ecosystem model, which was applied to data collected by a National Oceanic and Atmospheric Administration (NOAA)/Pacific Marine Environmental Laboratory (PMEL) mooring from 1995 to 2005. The physical model is forced by sea surface winds, heat and salt fluxes, tides, and sea ice. The biological model includes coupled pelagic and ice algae components. Model results are validated with daily mooring temperature, fluorometer, and daily Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) chlorophyll data. Two distinct ocean conditions and phytoplankton bloom patterns are related to the Pacific Decadal Oscillation (PDO) Index regimes: warmer temperature and later warm‐water phytoplankton species bloom in PDO > 1 year; colder temperature and earlier cold‐water phytoplankton species bloom in PDO < −1 year. Productivity of different phytoplankton species changed dramatically after the 1976 climate shift, but the total annual net primary production (NPP) remained flat over the past four decades under similar nutrient regulation. Climate shift also affected the vertical distribution of lower trophic level production and energy flow to the upper ocean pelagic ecosystem or the benthic community. A long‐term PDO regime shift occurred in 1976, and a short‐term PDO reversal occurred in 1998. Phytoplankton biomass responded promptly to both short‐ and long‐term climate changes. Zooplankton biomass responded more to the long‐term than to the short‐term climate shift. The model results captured observed trends of zooplankton abundance changes from the 1990s to 2004.
Decadal variability in North Atlantic phytoplankton blooms
Authors: Henson Stephanie A. , Dunne John P. , Sarmiento Jorge L.
Published: April 2009

The interannual to decadal variability in the timing and magnitude of the North Atlantic phytoplankton bloom is examined using a combination of satellite data and output from an ocean biogeochemistry general circulation model. The timing of the bloom as estimated from satellite chlorophyll data is used as a novel metric for validating the model's skill. Maps of bloom timing reveal that the subtropical bloom begins in winter and progresses northward starting in May in subpolar regions. A transition zone, which experiences substantial interannual variability in bloom timing, separates the two regions. Time series of the modeled decadal (1959–2004) variability in bloom timing show no long‐term trend toward earlier or delayed blooms in any of the three regions considered here. However, the timing of the subpolar bloom does show distinct decadal‐scale periodicity, which is found to be correlated with the North Atlantic Oscillation (NAO) index. The mechanism underpinning the relationship is identified as anomalous wind‐driven mixing conditions associated with the NAO. In positive NAO phases, stronger westerly winds result in deeper mixed layers, delaying the start of the subpolar spring bloom by 2–3 weeks. The subpolar region also expands during positive phases, pushing the transition zone further south in the central North Atlantic. The magnitude of the bloom is found to be only weakly dependent on bloom timing, but is more strongly correlated with mixed layer depth. The extensive interannual variability in the timing of the bloom, particularly in the transition region, is expected to strongly impact the availability of food to higher trophic levels.
Damping of Tropical Instability Waves caused by the action of surface currents on stress
Authors: Small R. Justin , Richards Kelvin J. , Xie Shang‐Ping , Dutrieux Pierre , Miyama Toru
Published: April 2009

Ocean eddies and fronts affect surface stress via two mechanisms: (1) ocean surface currents altering the relative motion between air and sea and, hence, the stress fields and (2) ocean sea surface temperature (SST) gradients forcing changes in stability and near‐surface winds. In this paper, we quantify the first effect and how it impacts Tropical Instability Waves (TIW) in the eastern Pacific. High‐resolution satellite data and a regional coupled model are used to distinguish between stress changes due to the surface currents and those due to the changes in stability and near‐surface winds. It is found that both mechanisms affect the surface stress curl, but they do so at different latitudes, allowing for their effect on Ekman pumping to be distinguished. The Ekman pumping due to the surface current effect alone, leads to significant damping of the TIWs. In terms of the eddy kinetic energy, the inclusion of surface current in the stress leads to decay with an e‐folding time comparable with the period of the TIWs. It is, thus, an important damping mechanism to be included in ocean and coupled ocean‐atmosphere models.
A case study of a mesospheric bore event observed with an all‐sky airglow imager at Tirunelveli (8.7°N)
Authors: Narayanan V. Lakshmi , Gurubaran S. , Emperumal K.
Published: April 2009

A prominent front separating bright and dark regions of all‐sky airglow images was recorded on the night of 22/23 March 2007, at the low‐latitude Indian station Tirunelveli (8.7°N, 77.8°E) and is attributed to a mesospheric bore. With the help of complementary wind information from the colocated MF radar and temperature and density data from the SABER instrument onboard TIMED mission, the parameters of the bore are calculated and discussed. Because the observed wind at the emission altitude was orthogonal to the direction of bore propagation, Doppler ducting was not likely to support the bore. The analysis that makes use of the square of buoyancy frequency profiles reveals a thermal duct that would provide favorable conditions for the propagation of the bore. This is the first report of a mesospheric bore event from the Indian sector.
Seasonality of isotopes in precipitation: A global perspective
Authors: Feng Xiahong , Faiia Anthony M. , Posmentier Eric S.
Published: April 2009

We use data from Global Network of Isotopes in Precipitation (GNIP) database to explore how the atmosphere's meridional circulation cells control the latitudinal and seasonal distribution of δ18O and d‐excess in precipitation. We demonstrate that the atmospheric general circulation (AGC) cells determine variations of zonally averaged isotopic composition of meteoric water; the local isotopic minimum near the equator coincides with the intertropical convergence (ITC), and two maxima on either side of the ITC coincide with the subtropical highs (STHs). Both the ITC and STHs migrate cum sole, as part of the systematic annual migration of the meridional cells. This migratory circulation pattern controls the phase of the annual oscillation of the precipitation δ18O. At latitudes equatorward of the STHs, δ18O reaches its maximum in the winter of the respective hemisphere and at higher latitudes in the summer. From the monthly latitudinal distribution of the vertical velocity at the 500‐hPa level, we obtain the seasonal variations of the latitudinal positions of the subtropical moisture source regions and their climates. The sea surface temperature and relative humidity at the moisture source regions are used to predict seasonal changes of the d‐excess of water vapor evaporated from the source regions. The GNIP data is consistent with the predicted phase of the d‐excess. However, the observed magnitude of the seasonal oscillation is greater than the predicted values. This work provides a baseline for understanding the influence of subtropical moisture source regions and other climatological factors on the d‐excess.
Cloud structure in Venus middle‐to‐lower atmosphere as inferred from VEX/VIRTIS 1.74 μm data
Authors: Satoh T. , Imamura T. , Hashimoto G. L. , Iwagami N. , Mitsuyama K. , Sorahana S. , Drossart P. , Piccioni G.
Published: April 2009

We have analyzed 1.74 μm nightside emission of Venus recorded using Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) onboard European Space Agency's (ESA) Venus Express (Orbit 344, 30–31 March 2007). Attention was paid to how infrared radiance, intense at the center of the 1.74 μm “window”, dims at an off‐center wavelength (1.71 μm). Cloud models are required to simultaneously reproduce the emission intensity at 1.74 μm and the ratio of intensities (I1.71μm/I1.74μm). Our best‐fit model (5 km vertical resolution) has located the main cloud opacity in 40–45 km altitude, lower than previous studies. This may be due to the use of CO2 line parameters from a relatively new source (Carbon Dioxide Spectroscopy Databank) which may also be responsible for weaker continuum absorption, 5.6 × 10−9 cm−1 amagat−2. The data are reproduced well by models of which total aerosol optical thickness is 30–50 plus subcloud haze at 30–40 km altitude. We have mapped the subcloud haze opacity (approximately 0–4) and found that the opacity basically anticorrelates with the 1.74 μm intensity. There are regions of “positive” correlation which may imply enhanced production of aerosols due to penetration of more sunlight in less cloudier regions. Venus Express, now with a capability of sensing “from the top to the bottom” of Venus cloud system, will greatly enhance our knowledge about the current status of Venus atmosphere.
Experimental analysis of braided channel pattern response to increased discharge
Authors: Egozi Roey , Ashmore Peter
Published: April 2009

Physical models of gravel braided rivers were used to investigate the adjustment of braiding intensity to step changes in channel‐forming discharge and the mechanisms by which channel pattern adjustment and maintenance occurs. A braided channel developed at low discharge was subjected to two step increases in discharge between which the channel was given time to develop stable average braiding intensity in response to each steady discharge. Active (with visible bed material movement) and total channel networks were mapped throughout the experiment. Total braiding intensity exceeded active braiding intensity and both adjusted to a stable, average value at each discharge, indicating that channel pattern adjustment to total discharge involves both the active and the total network. Only portions of the total braided channel network developed at a given time, and it formed progressively by migration and avulsion of the (less extensive) active network. At equilibrium, the ratio of active to total braiding intensity stabilized at about 0.4. This stable value may increase with relative mobility of the bed material (stream power relative to grain size). The stable value was achieved via gradual increase of total braiding intensity while active braiding intensity adjusted very quickly to the increased flow. These adjustments are controlled by partial avulsion of the main active channel associated with changes in its sinuosity, and allocation of flow and bed load to secondary anabranches. Braided channel pattern dynamics is closely tied to, and explained by, the local dynamics and symmetry/asymmetry of bifurcations and avulsions.
Comparing price and nonprice approaches to urban water conservation
Authors: Olmstead Sheila M. , Stavins Robert N.
Published: April 2009

Urban water conservation is typically achieved through prescriptive regulations, including the rationing of water for particular uses and requirements for the installation of particular technologies. A significant shift has occurred in pollution control regulations toward market‐based policies in recent decades. We offer an analysis of the relative merits of market‐based and prescriptive approaches to water conservation, where prices have rarely been used to allocate scarce supplies. The analysis emphasizes the emerging theoretical and empirical evidence that using prices to manage water demand is more cost effective than implementing nonprice conservation programs, similar to results for pollution control in earlier decades. Price‐based approaches may also compare favorably to prescriptive approaches in terms of monitoring and enforcement. Neither policy instrument has an inherent advantage over the other in terms of predictability and equity. As in any policy context, political considerations are also important.
Is the climate warming or cooling?
Authors: Easterling David R. , Wehner Michael F.
Published: April 2009

Numerous websites, blogs and articles in the media have claimed that the climate is no longer warming, and is now cooling. Here we show that periods of no trend or even cooling of the globally averaged surface air temperature are found in the last 34 years of the observed record, and in climate model simulations of the 20th and 21st century forced with increasing greenhouse gases. We show that the climate over the 21st century can and likely will produce periods of a decade or two where the globally averaged surface air temperature shows no trend or even slight cooling in the presence of longer‐term warming.
G‐protein signalling negatively regulates the stability of aryl hydrocarbon receptor
Authors: Nakata Asuka , Urano Daisuke , Fujii‐Kuriyama Yoshiaki , Mizuno Norikazu , Tago Kenji , Itoh Hiroshi
Published: April 2009

Aryl hydrocarbon receptor (AhR) is a transcription factor that works as a dioxin receptor and is also involved in various physiological phenomena, including development and cell proliferation. Here, we show that the Gα13 signal destabilizes AhR by promoting the ubiquitination of AhR. Gα13 interacts directly with AhR‐interacting protein (AIP) and inhibits the interaction between AhR and AIP, a crucial interacting protein of AhR. Strikingly, a reporter gene assay and a quantitative reverse transcription–PCR analysis indicate that the Gα13 signal shows a potent inhibitory effect on the ligand‐induced transcriptional activation of AhR. Gα13 results in the nuclear translocation of AhR in a ligand‐independent manner. However, in the presence of active Gα13, AhR fails to form the active transcriptional complex. Taken together, we propose a new negative regulation of dioxin signalling by the G protein.
Axin localizes to the centrosome and is involved in microtubule nucleation
Authors: Fumoto Katsumi , Kadono Moe , Izumi Nanae , Kikuchi Akira
Published: April 2009

Axin is known to have an important role in the degradation of β‐catenin in the Wnt pathway. Here, we reveal a new function of Axin at the centrosome. Axin was localized to the centrosome in various cell lines and formed a complex with γ‐tubulin. Knockdown of Axin reduced the localization of γ‐tubulin and γ‐tubulin complex protein 2—components of the γ‐tubulin ring complex—to the centrosome and the centrosomal microtubule nucleation activity after treatment with nocodazole. These phenotypes could not be rescued by the reduction in the levels of β‐catenin. Although the expression of Axin rescued these phenotypes in Axin‐knockdown cells, overexpression of Axin2, which is highly homologous to Axin, could not. Axin2 was also localized to the centrosome, but it did not form a complex with γ‐tubulin. These results suggest that Axin, but not Axin2, is involved in microtubule nucleation by forming a complex with γ‐tubulin at the centrosome.
UIMA in the Biocuration Workflow: A coherent framework for cooperation between biologists and computational linguists
Authors: Mellebeek Bart , Rodriguez-Penagos Carlos , Furlong Laura Ines
Published: April 2009

As collaborating partners, Barcelona Media Innovation Centre and GRIB (Universitat Pompeu Fabra) seek to combine strengths from Computational Linguistics and Biomedicine to produce a robust Text Mining system to generate data that will help biocurators in their daily work. The first version of this system will focus on the discovery of relationships between genes, SNPs (Single Nucleotide Polymorphisms) and diseases from the literature.A first challenge that we were faced with during the setup of this project is the fact that most current tools that support the curation workflow are complex, ad-hoc built applications which sometimes make difficult the interoperability and results sharing between research groups from different and unrelated expert fields. Often, biologists (even computer-savvy ones) are hard pressed to use and adapt sophisticated Natural Language Processing systems, and computational linguists are challenged by the intricacies of biology in applying their processing pipelines to elicit knowledge from texts. The flow of knowledge (needed to develop a usable, practical tool) to and from the parties involved in the development of such systems is not always easy or straightforward.The modular and versatile architecture of UIMA (Unstructed Information Management Architecture) provides a framework to address these challenges. UIMA is a component architecture and software framework implementation (including a UIMA SDK) to develop applications that analyse large volumes of unstructured information, and has been increasingly adopted by a significant part of the BioNLP community that needs industrial-grade and robust applications to exploit the whole bibliome. The use of UIMA to develop Text Mining applications useful for curation purposes allows the combination of diverse expertises which is beyond the individual know-how of biologists, computer scientists or linguists in isolation. A good synergy and circulation of knowledge between these experts is fundamental to the development of a successful curation tool.
Assistive Technology Toolkit to Increase Access to Early Learning Environments for Young Children With Disabilities
Authors: Sadao Kathleen C. , Brown Jennifer , Grant Debbie
Published: April 2009

The development of assistive technology (AT) and augmentative and alternative communication (AAC) interventions for young children with disabilities is rapidly expanding with a range of no-tech, low-tech, and high-tech approaches to provide access to adapted and augmented tools for participation in inclusive early childhood settings. Discrepancies exist in the legal requirements to consider AT and AAC for all children in the IFSP/IEP planning process. Researchers in the applications of AT and AAC with young children identify the importance of activity-based approaches that infuse AT methods and AAC systems within natural routines for young children. This article focuses on the development of an AT Toolkit Guide for early intervention and early childhood providers. The development of the AT Toolkit concept, content, and applications is based on research-based methods and tools with demonstrated effectiveness to promote language development, emergent literacy skills, play, mobility, and interaction with the environment for young children with disabilities. Suggested items, sources, applications and development guidelines for the SWEET AT Toolkit are provided.
Developing the Japanese Generic Medicines Market: What Can We Learn from Europe?
Authors: Simoens Steven
Published: April 2009

This paper originates from a ‘Generics Industry Forum’ that debated the development of the Japanese generic medicines retail market. Based on these discussions, the paper conducts a descriptive analysis of Japanese generic medicines policy and proposes recommendations for further developing the market by learning lessons from the European experience. The Japanese generic medicines market has benefited from measures that assure supply and quality of generic medicines, provide information about generic medicines, speed up registration of generic medicines on the reimbursement list, allow and reward generic substitution by pharmacists, increase patient co-payment, and reward physicians who adopt generic prescribing and/or who allow generic substitution. However, several factors hamper the development of this market, including extensions to the data exclusivity period and patent term of originator medicines, the requirement to launch the same generic medicine strengths as the originator medicine, mandatory reductions of reimbursement tariffs and weak incentives for physicians, pharmacists and patients to demand generic medicines. In order to sustain the development of the Japanese generic medicines market, a number of avenues were proposed that focused on speeding up market access of generic medicines, implementing a reference-pricing system and strengthening incentives for physicians, pharmacists and patients to demand generic medicines.
Institutional, Cultural and Contextual Factors: Potential Drivers of the Culinary Innovation Process
Authors: Ottenbacher Michael C. , Harrington Robert J.
Published: April 2009

This study compares the innovation process used by Michelin-starred chefs, and examines the potential impacts of institutional, cultural and contextual factors. The findings reveal a synthesis of similarities and differences used by the Spanish, German and US chefs. Similarities include a relatively sequential and top- down process and a stress on the importance of a closely connected network within culinary innovation. Key differences include the level of involvement throughout the process, the level at which technology is embraced in the process, the level of customer- focused decisions, and the likelihood of using test kitchens or food scientists in the innovation process.
White upconversion of rare-earth doped ZnO nanocrystals and its dependence on size of crystal particles and content of Yb3+ and Tm3+
Authors: Liu Yunxin , Xu Changfu , Yang Qibin
Published: April 2009

Rare earth (RE) doped ZnO nanocrystals were synthesized by chemical combustion method. Bright white upconversion (UC) luminescence with the CIE coordinates close to (0.33, 0.33) was obtained in Er+Tm+Yb tridoped ZnO nanocrystals under the excitation of a cost-effective 980 nm single-wavelength laser diode. The overall and relative UC luminescence intensities of RE doped ZnO nanocrystals were found to be depended highly on the diameter of crystal particles and the concentration of Yb3+ and Tm3+, for which the involved mechanisms were demonstrated. The investigation based on UC spectra, simplified energy level diagram, and excitation power dependence indicated that the remarkable enhancement of the green emission of the RE tridoped sample was due to a dual sensitization of Er3+ by Yb3+ and Tm3+ ions. The RE tridoped ZnO nanocrystals with the CIE coordinates close to (0.33, 0.33) are potentially suitable for the widely realistic application as the multicolor fluorescent labels, due to a fact that they could be cheaply and easily obtained and excited cost effectively.
High thermoelectric figure of merit and improved mechanical properties in melt quenched PbTe–Ge and PbTe–Ge1−xSix eutectic and hypereutectic composites
Authors: Sootsman Joseph R. , He Jiaqing , Dravid Vinayak P. , Li Chang-Peng , Uher Ctirad , Kanatzidis Mercouri G.
Published: April 2009

We report the synthesis, microstructure, and transport properties of composite thermoelectric materials based on the eutectic phase relationship between PbTe and Ge. When quenched, these eutectic mixtures exhibit considerably stronger mechanical strength and reduced brittleness compared to PbTe itself, while at the same time they possess lower lattice thermal conductivity. Thermal conductivity measurements show values lower than expected based on the law of mixtures and multiphase composites. We find that the thermoelectric performance in these composites can be tuned through the use of hypereutectic compositions and alloying of Ge with Si. PbI2 was used as an n-type dopant, and precise control of the carrier concentration was achieved to optimize the electrical transport and thermoelectric properties. ZT values approaching 1.3 at 778 K have been obtained in samples of PbTe–Ge0.8Si0.2(5%), which represent an ∼62% improvement over that of PbTe.
Assessment of a time-of-flight detection technique for measuring small velocities of cold atoms
Authors: Hagman H. , Sjölund P. , Petra S. J. H. , Nylén M. , Kastberg A. , Ellmann H. , Jersblad J.
Published: April 2009

A low noise time-of-flight detection system for laser cooled atoms has been constructed and incrementally optimized. Here, a thorough description of the construction is presented along with an analysis of the capabilities of the system. The quality of the detection (the resolution, the reproducibility, the sensitivity, etc.) is crucial for, e.g., the ability to see details in the velocity distribution profile, which is of interest for fundamental studies of statistical physics and of the laser cooling processes, and for detection of small initial velocities of an atomic cloud, important, e.g., when studying small drifts induced by Brownian motors and ratchets. We estimate the signal-to-noise ratio of our signal to be better than 1000:1 for a typical single shot, and we discuss the effect of the initial atomic cloud size, the probe size, and the effects of the wave packet spread during the fall time on the measured quantities. We show that the shape of the velocity distribution is well conserved during the mapping done in the detection, i.e., in the convolution with the probe beam, and that velocities as small as a few percent of the single photon recoil velocity can be resolved.
The Li3PO4/Al bilayer: An efficient cathode for organic light emitting devices
Authors: Gassmann Andrea , Melzer Christian , von Seggern Heinz
Published: April 2009

In this contribution an efficient cathode material for organic light emitting diodes (OLEDs) is introduced consisting of a thin layer of the metal salt lithium phosphate (Li3PO4) deposited between the organic semiconductor and an Al cathode. The bilayer cathode Li3PO4/Al enables a device performance of small molecule based OLEDs competitive to the benchmark cathode LiF/Al. While current densities and luminances of both systems are alike, the use of Li3PO4 substantially increases the device lifetime. It will be shown that the improved device characteristics can be ascribed to a stably enhanced electron injection. We demonstrate that neither a field enhancement across the Li3PO4 layer due to accumulated holes nor a possible charge transfer doping by the Li3PO4 is the reason for the improved electron injection. Investigation of the Li3PO4/Al interface by Kelvin probe techniques disclosed a work function lowering of the cathode that facilitates electron injection and finally explains the improvement in performance of respective organic light emitting diodes.
Large-area metamaterials on thin membranes for multilayer and curved applications at terahertz and higher frequencies
Authors: Peralta X. G. , Wanke M. C. , Arrington C. L. , Williams J. D. , Brener I. , Strikwerda A. , Averitt R. D. , Padilla W. J. , Smirnova E. , Taylor A. J. , O’Hara J. F.
Published: April 2009

A possible path for fabricating three-dimensional metamaterials with curved geometries at optical and infrared frequencies is to stack flexible metamaterial layers. We have fabricated highly uniform metamaterials at terahertz frequencies on large-area, low-stress, free-standing 1 μm thick silicon nitride membranes. Their response remains comparable to that of similar structures on thick substrates as measured by the quality factor of the resonances. Transmission measurements with a Fourier transform infrared spectrometer highlight the advantage of fabricating high frequency metamaterials on thin membranes as etalon effects are eliminated. Releasing the membranes enables layering schemes and placement onto curved surfaces in order to create three-dimensional structures.