bluuebunny/crossref_metadata_2025 huggingface dataset:
A Dust Monitoring Programme for Desertification Control in West Africa
Authors: McTainsh Grant H.
Published: August 2009

To date, the principal constraint upon the implementation of a dust monitoring programme for desertification control in West Africa, is our limited knowledge of the dust processes to be monitored. A review of the state of dust research in Africa and over the Atlantic reveals a strong imbalance in favour of the latter, and resolves some misconceptions concerning dust source-areas and the relative importance of winter and summer dust. The results of Atlantic Ocean dust research are here brought together with the recent results of Harmattan dust research in Nigeria to demonstrate, at least tentatively, that the Harmattan and winter dust comprise a contiguous aeolian process system referred to as the Harmattan aeolian system.

The Harmattan aeolian system is used here as a conceptual framework for the dust monitoring programme. Three dust process-zones are identified, within which three basic aeolian processes operate: dust entrainment (primary and secondary), dust transport, and dust deposition (primary and secondary). Within each dust process-zone, standardized dust collection, measurement, and analysis techniques, are proposed for a network of monitoring sites. Entrainment and transport can be measured — directly using aerosol pump-samplers and indirectly by relating dust-aerosol concentration to solar radiation and visibility. The indirect approach has the advantage that it opens up a large body of historical data on dust and, therefore, desertification. Deposition can be measured using dust-traps. The importance of such aspects as site characteristics, measurement period, and laboratory methods, are also discussed. Finally, a minimal administrative structure is suggested, allowing for the possibility of UNEP or other major support.
Infestation by Aquatic Weeds of the Fern GenusSalvinia: Its Status and Control
Authors: Abbasi S.A. , Nipaney P.C.
Published: August 2009

The paper starts with a report on the growing predominance of aquatic weeds of the genusSalviniain the waterbodies of the world. The various ways in whichSalvinia molesta, particularly, causes pollution and depletion water resources are then reviewed, as are the attempts made so far to control and eradicateSalviniathrough chemical, biological, and mechanical, means. It is shown not only that these attempts have failed to achieve their purpose but also that there are possibilities of environmental backlashes being caused by the introduction of chemicals or bioagents into the environment. The importance developing environmentally safe methods of utilizationSalviniahas been stressed, so that the cost of mechanical removal of the weed can be offset by the profits earned through its utilization.
Nicaragua's Environmental Problems, Policies, and Programmes
Authors: Pfeiffer Egbert W.
Published: August 2009

Nicaragua is the largest (geographical area) country in Central America, but has the lowest population per hectare. For the last half-century its rich natural resources—timber, fruits, and minerals—were exploited by North American and European corporations without any regard for basic ecological principles. Furthermore, early in the 1950s, cotton was introduced and became the main source of foreign exchange. This led to massive use of pesticides, and construction of pesticide manufacturing plants, causing disastrous pollution by mercury of Lakes Managua and Nicaragua. It also forced migration of thousands of local subsistence farmers from the lowland cotton-producing areas to the hills where the farmers' ‘slash and burn’ techniques exacerbated the damage already done to the forests by foreign companies.
Can Hydro-reservoirs in Tropical Moist Forests be Environmentally Sustainable?
Authors: Goodland Robert J.A. , Juras Anastacio , Pachauri Rajendra
Published: August 2009

Today's polarization of society ‘for’ or ‘against’ big hydro-projects relates to environmental costs, which are borne particularly by vulnerable ethnic minorities and the poor; such costs include species extinctions and tropical deforestation. This counter-productive polarization can be reconciled by transparency and mutuality of planning, by pluralism involving the local populace and especially all affected people, and by engendering national consensus on the best project that is available and practicable.
Sensitivity of environmental sampling methods for detectingSalmonellaEnteritidis in commercial laying flocks relative to the within-flock prevalence
Authors: ARNOLD M. E. , CARRIQUE-MAS J. J. , DAVIES R. H.
Published: August 2009

The objective of this study was to estimate the sensitivity of three different sampling/testing methodologies for the detection ofSalmonellaEnteriditis in commercial egg-laying flocks relative to the within-flock prevalence. The following methods were compared on 21 farms: (1) The European Union (EU) baseline survey method (five faecal and two dust samples); (2) an in-house method that involved collecting 10 dust and 10 faecal samples into jars with buffered peptone water, and (3) a method involving single samples of pooled faeces and dust that has been adopted as a monitoring method for the National Control Programme across the EU (the NCP method). Testing of individual bird ovaries/oviduct and caeca was carried out on each flock, and the sensitivity of each sampling method was estimated relative to the within-flock prevalence using Bayesian methods. Results showed that the sensitivity of all the sampling methods increased as the within-flock prevalence increased, and that all were more efficient than individual bird sampling for detection ofS. Enteriditis in commercial flocks. The in-house method was the most sensitive of the methods compared, with a 98% power to detect a 0·1% prevalence, and the NCP method the least sensitive, with a 93% power to detect a prevalence of 20%.
Development of English referring expressions in the narratives of Chinese–English bilinguals
Authors: CHEN LIANG , PAN NING
Published: August 2009

This paper investigates the development of referring expressions in the narratives of children learning English as a second language (L2). Spoken narratives in English were elicited from sixty Chinese-speaking participants at four ages – five, eight, ten, and young adults – using the wordless picture bookFrog, where are you?(Mayer, 1969). Narrative analysis focused on the referring expressions that the L2 speakers used to introduce and maintain reference to story characters in the narratives and on the referential appropriateness of those expressions. We then compared the results of this study with other, similar studies on children learning English as a first language (L1) and found both universal and L2-specific patterns in the development of referring expressions in discourse. On the one hand, regardless of whether English is acquired as an L1 or L2, appropriate use of referring expressions in discourse is developed gradually and is influenced by both discourse function (introduction vs. maintenance) and character type (main vs. secondary). On the other hand, L2 children in our study differed from L1 children in previous studies in the development of referential appropriateness in character introduction, the use of pronominals for referent maintenance, and the timeline of the mastery of appropriate forms for referent introductions versus referent maintenance.
Characterization and location of infrasonic sources in active volcanoes: Mount Etna, September–November 2007
Authors: Cannata A. , Montalto P. , Privitera E. , Russo G.
Published: August 2009

The period September–November 2007 was characterized at Mount Etna by explosive activity and intense degassing. During this time interval, infrasonic signals were recorded by an infrasonic network. By a triggering procedure, about 1000 infrasonic events were found, characterized by very high signal‐to‐noise ratio and grouped into nine families. Successively, the spectral analysis allowed subdividing these nine families into three clusters based on the peak frequency and the quality factor of the events. Finally, by the location analysis a cluster (cluster 1) was related to the degassing activity of the northeast crater (NEC), while the other two (clusters 2 and 3) to the explosive activity of the southeast crater (SEC). The comparison between the stacked infrasonic waveforms, interpreted as generated by the vibration of large gas bubbles, and the synthetic ones, permitted to calculate radius, length of the bubble, and initial overpressure, by a genetic algorithm method. The higher overpressure values of cluster 3 compared to the cluster 2 values were in good agreement with the stronger intensity of the explosions accompanying the infrasonic events of cluster 3. The variation of both intensities and waveforms is tentatively attributed to the occasional accumulation of lithic clasts (due to moderate landslides?) on the explosive vent. Indeed, events belonging to cluster 3 were no longer observed once the landslides had ended. Finally, the daily emitted gas volume, related to the active degassing, was estimated for NEC and SEC by using the infrasonic data during the studied period.
Effects of bora wind on physical and biogeochemical properties of stratified waters in the northern Adriatic
Authors: Boldrin A. , Carniel S. , Giani M. , Marini M. , Bernardi Aubry F. , Campanelli A. , Grilli F. , Russo A.
Published: August 2009

Wind forcing plays a key role in controlling the water column structure and circulation in the northern Adriatic Sea. Through shipboard observations and numerical modeling, we have documented the changing of oceanographic features before, during, and after a sequence of cold northeasterly bora wind pulses that occurred during stratified conditions in late September 2002. High‐resolution meteorological, hydrodynamic, and wave model outputs were related to in situ observations of hydrologic parameters, dissolved nutrients and oxygen, suspended matter biogeochemical properties, and phytoplankton. The bora intensified the southward flowing coastal current along the Italian coast, establishing a frontal system that typically exists in winter. The bora also caused complete vertical mixing to 20–25 m in the water column, an influx of warm salty water from the south along the Croatian coast, and increased resuspension and southward transport of bottom sediments for the combined effects of currents and waves. The effects on the bottom were limited to the western coastal belt, as in the deeper central part of the basin hypoxic conditions were present during the whole observing period. During the bora, the concentration of inorganic dissolved nutrients in the bottom water increased consistently with the release of nutrients from the sediments and with the mineralization processes. Resuspension of bottom layer sediment represents an important source of nutrients for the water column in this period. The higher level of nutrients was observed together with an increase in phytoplankton biomass, suggesting a potential trigger for the autumnal phytoplankton bloom in the northern Adriatic. Finally, bora events seem to be able to generate a relevant increase of nutrient export from the northern Adriatic through the intensified Adriatic western coastal current, so they could play a relevant role in the nutrient balance of the basin.
A ground‐to‐exosphere Martian general circulation model: 2. Atmosphere during solstice conditions—Thermospheric polar warming
Authors: González‐Galindo F. , Forget F. , López‐Valverde M. A. , Angelats i Coll M.
Published: August 2009

A ground‐to‐exosphere Martian general circulation model is applied to study the thermal and dynamical structure of the upper Martian atmosphere during solstitial conditions. Special attention is paid to the reproduction of the thermospheric polar warming observed by Mars Odyssey during southern hemisphere (SH) summer solstice. The intensity and latitudinal distribution of this polar warming are successfully reproduced by the model. The heating balance and the dynamical structure of the upper atmosphere are studied. It is shown that a strong interhemispheric transport produces a convergence and descent of air over the winter pole, producing an adiabatic heating and a polar warming. This structure confirms previous results made by other models. The most novel aspect of this study is a sensitivity study showing the importance of the tides excited in situ in the upper atmosphere. These tides are critical to the simulated thermal and dynamical structure and remain key components of the interhemispheric transport mechanism responsible for the thermospheric polar warming. The day‐night temperature differences created by these in situ tides produce a day‐night transport that reinforces the summer‐to‐winter circulation and the descent of air over the pole, becoming an essential factor for this thermospheric polar warming. The effect of upward propagating nonmigrating tides is also studied.
Topographic and ecologic controls on root reinforcement
Authors: Hales T. C. , Ford C. R. , Hwang T. , Vose J. M. , Band L. E.
Published: August 2009

Shallow landslides are a significant hazard in steep, soil‐mantled landscapes. During intense rainfall events, the distribution of shallow landslides is controlled by variations in landscape gradient, the frictional and cohesive properties of soil and roots, and the subsurface hydrologic response. While gradients can be estimated from digital elevation models, information on soil and root properties remains sparse. We investigated whether geomorphically controlled variations in ecology affect the spatial distribution of root cohesion by measuring the distribution and tensile strength of roots from soil pits dug downslope of 15 native trees in the southern Appalachian Mountains, North Carolina, United States. Root tensile strengths from different hardwood tree species were similar and consistently higher than the only native shrub species measured (Rhododendron maximum). Roots were stronger in trees found on noses (areas of divergent topography) relative to those in hollows (unchanneled, convergent topography) coincident with the variability in cellulose content. This cellulose variability is likely related to topographic differences in soil water potential. For all species, roots were concentrated close to the soil surface, with roots in hollows being more evenly distributed in the soil column than those on noses. Trees located on noses had higher mean root cohesion than those in hollows because of a higher root tensile force. R. maximum had the shallowest, weakest roots suggesting that recent expansion of this species due to fire suppression has likely lowered the root cohesion of some hollows. Quantification of this feedback between physiologic controls on root growth and slope hydrology has allowed us to create a curvature‐based model of root cohesion that is a significant improvement on current models that assume a spatially averaged value.
Visibility network of United States hurricanes
Authors: Elsner J. B. , Jagger T. H. , Fogarty E. A.
Published: August 2009

The authors demonstrate how to construct a network from a time series of U.S. hurricane counts and show how it can be used to identify unusual years in the record. The network links years based on a “line‐of‐sight” visibility algorithm applied to the time series plot and is physically related to the variation of hurricanes from one year to the next. The node degree is the number of links connected to a node. The authors find that the distribution of node degree is consistent with a random Poisson process. High hurricane‐occurrence years that are surrounded by years with few hurricanes have many linkages. Of the environmental conditions known to affect coastal hurricane activity, they find years with little sunspot activity during September (peak month of the hurricane season) best correspond with the unusually high linkage years.
Effect of frequency modulation on whistler mode waves in the magnetosphere
Authors: Streltsov A. V. , Gołkowski M. , Inan U. S. , Papadopoulos K. D.
Published: August 2009

We present results from numerical studies of whistler mode wave propagation in the Earth's magnetosphere. Numerical simulations, based on the novel algorithm, solving one‐dimensional electron‐MHD equations in the dipole coordinate system, demonstrate that the amplitude (and power) of the whistler mode waves generated by the ground‐based transmitter can be significantly increased in some particular location along the magnetic field line (for example, at the equatorial magnetosphere) by the frequency modulation of the transmitted signal. The location where the amplitude of the signal reaches its maximum is defined by the time delay between different frequency components of the signal. Simulations reveal that a whistler mode wave with a discrete frequency modulation (where the frequency changes by a finite step) in the range from 1 to 3 kHz can be compressed as efficiently as a signal with a continuous frequency modulation when the frequency difference between components of the discrete‐modulated signal is not greater than 100 Hz.
Ecological dynamics and the basis of sympatric phenotypic diversification
Authors: Pineda-Krch Mario , Svanbäck Richard , Doebeli Michael
Published: August 2009

Theoretical and empirical studies are showing evidence in support of evolutionary branching and sympatric speciation due to frequency‐dependent competition. However, phenotypic diversification due to underlying genetic diversification is only one possible evolutionary response to disruptive selection. Another potentially general response is phenotypic diversification in the form of phenotypic plasticity. It has been suggested that genetic variation is favored in stable environments, whereas phenotypic plasticity is favored in unstable and fluctuating environments. We investigate the “competition” between the processes of evolutionary branching and the evolution of phenotypic plasticity in a predator‐prey model that allows both processes to occur. In this model, environmental fluctuations can be caused by complicated population dynamics. We found that the evolution of phenotypic plasticity was generally more likely than evolutionary branching when the ecological dynamics exhibited pronounced predator‐prey cycles, whereas the opposite was true when the ecological dynamics was more stable. At intermediate levels of density cycling, trimorphisms with two specialist branches and a phenotypically plastic generalist branch sometimes occurred. Our theoretical results suggest that ecological dynamics and evolutionary dynamics can often be tightly linked and that an explicit consideration of population dynamics may be essential to explain the evolutionary dynamics of diversification in natural populations.
Short and long distance translocations: Movement and survival in eastern box turtles (Terrapene carolina carolina)
Authors: Farnsworth Scott , Seigel Richard , Cain Patrick
Published: August 2009

Background/Question/Methods

Human development represents a serious threat to wildlife populations through continued habitat loss and incidental mortality from construction activities. Resource managers responsible for protecting species with legal status or high public profile are faced with difficult decisions on how to best manage populations located in construction zones. One approach to mitigate mortalities is to relocate individuals. The effectiveness of translocation for reptiles and amphibians has been questioned, with studies often reporting higher mortality and increased movements of translocated individuals. Translocations of reptiles and amphibians have primarily involved moving animals long distances, well beyond an individual’s home range. For reptiles this means finding new nesting, foraging, and overwintering sites, which may be problematic. Moving individuals only short distances, within their home range, may reduce those problems. As part of the mitigation plan for a highway construction project in central Maryland, groups of eastern box turtles (Terrapene carolina carolina) were translocated both short distances (<0.5km), and long distances (~5km). To investigate differences in survival and movement patterns among long distance translocation, short distance translocation, and non-translocation groups, I tracked 94 turtles (31 long distance translocation, 29 short distance translocation, and 34 non-translocation) using radio telemetry.

Results/Conclusions

Eleven animals died during the first activity season after translocation (April through November 2008). The mortalities included two long distance translocation, six short distance translocation, and three non-translocation animals. The causes of mortality included road kill, construction activity, and unknown (1, 4, and 6 mortalities respectively). All construction related mortalities were a result inadequate exclusion fencing to keep turtles from trespassing back onto the construction site. All mortalities due to construction were either non-translocation or short distance translocation animals. Eleven other individuals were located at least once within the construction zone, suggesting that without our intervention mortality rates would have been much higher. Preliminary results for movement show that turtles in the non-translocation group had the lowest average movements while long distance translocation animals had the greatest average movements. Long distance translocation turtles also chose overwintering sites farther away from their initial overwintering sites than either short distance translocation or non-translocation turtles (average distance from original site of 261.8m, 155.6m, and 124.3m respectively). This suggests that movement patterns of short distance translocation turtles are more like native turtles.
Habitat use of Northern Map Turtles (Graptemys geographica) in an altered system, the Susquehanna River, Maryland (USA)
Authors: Richards Teal , Seigel Richard
Published: August 2009

Background/Question/Methods

Riverine turtle populations are declining worldwide and many of these species have been extirpated from large areas of their range. In Maryland, the northern map turtle (Graptemys geographica) occurs only in the lower Susquehanna River, which is the eastern edge of its range. The northern map turtle is a Maryland state endangered species and had not been seen in Maryland since the early 1990’s. The Susquehanna River is divided by a hydroelectric dam and is heavily used for recreational activities, both of which may negatively impact turtles. To determine the status of map turtles in Maryland, we performed visual encounter surveys for basking turtles at 12 sites from April to November 2008.

Results/Conclusions

Overall, we observed 0-38 map turtles per day. The largest consistent aggregations of adult turtles were found at an island complex 5.9 km below the dam. Some aggregations were quite large, with as many as 21 turtles observed basking on a single rock. Observed basking activity began by 12 April and stayed more or less constant through June. Observed basking activity was reduced between July and September, and then increased in mid-September continuing through early November. Most map turtles observed were adults, and the only evidence of ongoing reproduction and recruitment was two small juveniles found above the hydroelectric dam. The adult sex ratio was female biased throughout the study period, with daily sex ratios as high as 33F:2M. This may represent sampling bias (females are much larger than males and are thus easier to detect) or the actual population sex ratio in Maryland is dominated by females. We surveyed for nesting habitat both above and below the hydroelectric dam, by looking for predated nests at potential nesting beaches, but no depredated nests were found. Virtually nothing is known about what specific areas of the Susquehanna River and its tributaries are used for the various aspects of the map turtle’s life histories or what potential negative effects may be caused the by river impoundment and recreation activities. Given the absence of basic ecological data of map turtles in Maryland, we are using radio telemetry, diet analysis, and visual surveys to continue to gather information on nesting, feeding, mating, basking, and hibernation, and how these activities are affected by anthropogenic alterations to the Susquehanna River.
The Right Answers to the Wrong Questions? Observations on Skill Development and Training in the United Kingdom's Hospitality Sector
Authors: Lashley Conrad
Published: August 2009

This article is informed by a literature review of current research on skills and skills development undertaken for People 1st, the Sector Skills Council covering hospitality, gaming, leisure and tourism activities in England. The article suggests that much government policy towards skills needs in the sector is based on a number of erroneous assumptions. Fundamentally, State training interventions chiefly involve education and training supply, and not low levels of employer demand for training, or low employer demand for a highly skilled workforce in the sector. There is a culture of training avoidance in many UK firms in the hospitality sector. Ironically, education and training policies are exclusively influenced by employers in national government, and this assumes that sector employers represent a homogeneous group. Yet there are many differences between firms and their different demands for varied skills sets in the workforce. The assumption that employers are looking for hard skills in employees is also questionable. In fact, there are a number of different skill clusters that employers seek, and each operates under different labour market conditions. For example, much of the discourse about the shortage of chefs assumes that one set of skills exists for those who cook; this article suggests that there are at least three different skills levels. The article ultimately argues that People 1st and those making training policy for the sector are often working from flawed assumptions. They need to ask why so many firms are training avoiders, and to listen to a wider audience of stakeholders than merely employers. This would allow them to develop a much more sophisticated understanding of the demand for labour in hospitality firms.
Assessment of semen quality, sperm cryopreservation and heterologous IVF in the critically endangered Iberian lynx (Lynx pardinus)
Authors: Gañán Natalia , González Raquel , Garde J. Julián , Martínez Fernando , Vargas Astrid , Gomendio Montserrat , Roldan Eduardo R. S.
Published: August 2009

Semen traits and factors affecting sperm cryopreservation were assessed in the Iberian lynx (Lynx pardinus), a species regarded as the most endangered felid in the world. For cryopreservation, semen was washed, resuspended in a Tes–Tris-based diluent (TEST) or a Tris-based diluent (Biladyl), both with 20% egg yolk and 4% glycerol, loaded into straws, cooled to 5°C using an automated programmable system and frozen on nitrogen vapour. Heterologous IVF of in vitro-matured domestic cat oocytes was used to test the fertilising ability of cryopreserved spermatozoa. Electroejaculates from five males were obtained. Characterisation of the electroejaculates revealed mean (± s.e.m.) values of 3.3 ± 0.6 × 106 total spermatozoa, 73.6 ± 4.6% motile spermatozoa, 23.7 ± 4.0% morphologically normal spermatozoa and 40.7 ± 2.3% spermatozoa with intact acrosomes. After thawing a higher percentage of motile spermatozoa was seen in TEST than in Biladyl (34.0 ± 6.2% v. 7.5 ± 4.8%, respectively; P < 0.05); however, there were no differences in the percentage of intact acrosomes between the two diluents. Iberian lynx spermatozoa fertilised domestic cat oocytes in vitro, with higher fertilisation rates observed for spermatozoa cryopreserved in TEST than in Biladyl, although the difference did not reach statistical significance (20.5 ± 4.5% v. 11.5 ± 6.8%, respectively). There were positive significant relations between the fertilisation rates and both the percentage of normal spermatozoa and the percentage of spermatozoa with an intact acrosome before cryopreservation (P = 0.04). This first report of the collection and cryopreservation of Iberian lynx semen and analysis of fertilising ability is an important step in the development of assisted reproductive techniques for this critically endangered felid species.
Preputialectomised and intact adult male mice exhibit an elevated urinary ratio of oestradiol to creatinine in the presence of developing females, whilst promoting uterine and ovarian growth of these females
Authors: Khan Ayesha , Berger Robert G. , deCatanzaro Denys
Published: August 2009

Exposure to novel adult males and their urine can hasten the onset of sexual maturity in female mice. Some evidence implicates chemosignals from males’ preputial glands, while other evidence suggests that male urinary steroids, especially 17β-oestradiol, contribute to this effect. The present experiment was designed to determine whether preputial gland removal would influence the capacity of males to accelerate female sexual development, and to measure male urinary oestradiol and testosterone in the presence or absence of these glands. Juvenile females aged 28 days were housed for two weeks in isolation or underneath two outbred males that had undergone preputialectomy or sham surgery. Urine samples were collected non-invasively from males that were isolated or exposed to females, then assayed for oestradiol, testosterone and creatinine. Combined uterine and ovarian mass from females sacrificed at 43 days of age was increased by exposure to males, regardless of whether or not these males had been preputialectomised. Male urinary creatinine was reduced by exposure to developing females. Creatinine-adjusted oestradiol and testosterone were significantly greater in female-exposed than in isolated males, in both preputialectomised and intact males. These data suggest that the preputials are not necessary for the capacity of males to hasten female uterine and ovarian growth. As exogenous oestrogens can promote uterine growth and other parameters of female reproductive maturation, oestradiol in males’ urine may contribute to earlier sexual maturity in male-exposed females.
Factor XII gene expression in endometrial stromal cells during decidualisation
Authors: Kawato Hiroaki , Tabata Tsutomu , Minoura Hiroyuki , Murabayashi Nao , Ma Ning , Wang Dong Fang , Sagawa Norimasa
Published: August 2009

Decidualisation of endometrial stromal cells (ESC) is a prerequisite for the implantation of human embryos. Identification of genes that are upregulated or downregulated during decidualisation could lead to a better understanding of the molecular mechanisms involved in this process. In the present study, we examined differences in gene expression between decidualised and non-decidualised cells using microarray analysis and found that Factor XII (FXII) gene expression was upregulated during decidualisation. Furthermore, we also examined the expression of FXII by human ESC before and during pregnancy, as well as its expression by cells that had undergone decidualisation in vitro. Weak expression of FXII mRNA was detected in the non-pregnant endometrium that increased gradually from the proliferative to the secretory endometrium. During pregnancy, FXII mRNA expression was markedly increased in decidualised endometrium. When sex steroids (200 pg mL–1 of 17β-oestradiol and 100 ng mL–1 of progesterone) were used to induce in vitro decidualisation of ESC, the expression of FXII mRNA increased by approximately 25.3-fold compared with that in non-decidualised ESC. Using western blotting, we confirmed the presence of FXII protein (80 kDa) in ESC after in vitro decidualisation. Increased expression of FXII in ESC during decidualisation suggests that the kallikrein–kininogen–kinin system may be activated during the implantation of human embryos.
Effect of undernutrition on the uterine environment during maternal recognition of pregnancy in sheep
Authors: Sosa C. , Abecia J. A. , Carriquiry M. , Vázquez M. I. , Fernández-Foren A. , Talmon M. , Forcada F. , Meikle A.
Published: August 2009

The effects of pregnancy and undernutrition on endometrial gene expression were investigated in ewes fed all or half their maintenance requirements and killed on Day 14 of pregnancy or of the oestrous cycle. The endometrial expression of progesterone, oestrogen, oxytocin and interferon receptors (PR, ERα, OXTR and IFNAR, respectively), cyclo-oxygenase (COX)-2, proliferating cell nuclear antigen (PCNA), insulin-like growth factors (IGF)-I and -II, and IGF-1 receptor (IGF-1R) was studied by immunohistochemistry or real-time reverse transcription–polymerase chain reaction. The luminal epithelium of cyclic control ewes was devoid of PR staining and had relatively high levels of ERα, OXTR, COX-2 and IFNAR2. The presence of a conceptus decreased the in vitro uterine secretion of prostaglandin (PG) F2α and the expression of IFNAR2 in most cell types, and increased the gene expression of IGF-I and IGF-II. Undernutrition tended to increase ERα protein and gene, but decreased in vitro uterine secretion of PGE2 and the gene expression of IFNAR2 in cyclic ewes. There was no effect of undernutrition on pregnancy rates or the number of conceptuses recovered. Consistent with this, undernutrition of pregnant ewes did not have any effect on uterine gene expression. Moreover, in cases where changes were observed in cyclic ewes, these changes were negated when a conceptus was present.
Alexander Meissner: Learning the reprogramming code
Authors: Short Ben
Published: August 2009

Meissner studies the epigenomics of pluripotent cells.
AURKB-mediated effects on chromatin regulate binding versus release of XIST RNA to the inactive chromosome
Authors: Hall Lisa L. , Byron Meg , Pageau Gayle , Lawrence Jeanne B.
Published: August 2009

How XIST RNA strictly localizes across the inactive X chromosome is unknown; however, prophase release of human XIST RNA provides a clue. Tests of inhibitors that mimic mitotic chromatin modifications implicated an indirect role of PP1 (protein phosphatase 1), potentially via its interphase repression of Aurora B kinase (AURKB), which phosphorylates H3 and chromosomal proteins at prophase. RNA interference to AURKB causes mitotic retention of XIST RNA, unlike other mitotic or broad kinase inhibitors. Thus, AURKB plays an unexpected role in regulating RNA binding to heterochromatin, independent of mechanics of mitosis. H3 phosphorylation (H3ph) was shown to precede XIST RNA release, whereas results exclude H1ph involvement. Of numerous Xi chromatin (chromosomal protein) hallmarks, ubiquitination closely follows XIST RNA retention or release. Surprisingly, H3S10ph staining (but not H3S28ph) is excluded from Xi and is potentially linked to ubiquitination. Results suggest a model of multiple distinct anchor points for XIST RNA. This study advances understanding of RNA chromosome binding and the roles of AURKB and demonstrates a novel approach to manipulate and study XIST RNA.
Cortactin regulates cofilin and N-WASp activities to control the stages of invadopodium assembly and maturation
Authors: Oser Matthew , Yamaguchi Hideki , Mader Christopher C. , Bravo-Cordero J.J. , Arias Marianela , Chen Xiaoming , DesMarais Vera , van Rheenen Jacco , Koleske Anthony J. , Condeelis John
Published: August 2009

Invadopodia are matrix-degrading membrane protrusions in invasive carcinoma cells. The mechanisms regulating invadopodium assembly and maturation are not understood. We have dissected the stages of invadopodium assembly and maturation and show that invadopodia use cortactin phosphorylation as a master switch during these processes. In particular, cortactin phosphorylation was found to regulate cofilin and Arp2/3 complex–dependent actin polymerization. Cortactin directly binds cofilin and inhibits its severing activity. Cortactin phosphorylation is required to release this inhibition so cofilin can sever actin filaments to create barbed ends at invadopodia to support Arp2/3-dependent actin polymerization. After barbed end formation, cortactin is dephosphorylated, which blocks cofilin severing activity thereby stabilizing invadopodia. These findings identify novel mechanisms for actin polymerization in the invadopodia of metastatic carcinoma cells and define four distinct stages of invadopodium assembly and maturation consisting of invadopodium precursor formation, actin polymerization, stabilization, and matrix degradation.
A requirement for epsin in mitotic membrane and spindle organization
Authors: Liu Zhonghua , Zheng Yixian
Published: August 2009

Eukaryotic cells possess a sophisticated membrane system to facilitate diverse functions. Whereas much is known about the nature of membrane systems in interphase, the organization and function of the mitotic membrane system are less well understood. In this study, we show that epsin, an endocytic adapter protein, regulates mitotic membrane morphology and spindle integrity in HeLa cells. Using epsin that harbors point mutations in the epsin NH2-terminal homology domain and spindle assembly assays in Xenopus laevis egg extracts, we show that epsin-induced membrane curvature is required for proper spindle morphogenesis, independent of its function in endocytosis during interphase. Although several other membrane-interacting proteins, including clathrin, AP2, autosomal recessive hypercholesterolemia, and GRASP65, are implicated in the regulation of mitosis, whether they participate through regulation of membrane organization is unclear. Our study of epsin provides evidence that mitotic membrane organization influences spindle integrity.
Crystal structure of the complete integrin αVβ3 ectodomain plus an α/β transmembrane fragment
Authors: Xiong Jian-Ping , Mahalingham Bhuvaneshwari , Alonso Jose Luis , Borrelli Laura Ann , Rui Xianliang , Anand Saurabh , Hyman Bradley T. , Rysiok Thomas , Müller-Pompalla Dirk , Goodman Simon L. , Arnaout M. Amin
Published: August 2009

We determined the crystal structure of 1TM-αVβ3, which represents the complete unconstrained ectodomain plus short C-terminal transmembrane stretches of the αV and β3 subunits. 1TM-αVβ3 is more compact and less active in solution when compared with ΔTM-αVβ3, which lacks the short C-terminal stretches. The structure reveals a bent conformation and defines the α–β interface between IE2 (EGF-like 2) and the thigh domains. Modifying this interface by site-directed mutagenesis leads to robust integrin activation. Fluorescent lifetime imaging microscopy of inactive full-length αVβ3 on live cells yields a donor–membrane acceptor distance, which is consistent with the bent conformation and does not change in the activated integrin. These data are the first direct demonstration of conformational coupling of the integrin leg and head domains, identify the IE2–thigh interface as a critical steric barrier in integrin activation, and suggest that inside-out activation in intact cells may involve conformational changes other than the postulated switch to a genu-linear state.
Super-coil me: Sizing up centromeric nucleosomes
Authors: Hill Emma , Williams Ruth
Published: August 2009

Every chromosome needs a centromere for proper segregation during cell division. Centromeric chromatin wraps around histones, providing an anchor for kinetochore proteins and spindle attachment. It is clear why cells need centromeres, but how they form and what they look like is less so. Recent reports extend our understanding of chaperones involved in centromere formation. And other accounts of half-sized, right-handed nucleosomes have created an unexpected twist.
Grieg's Slåtter, Op. 72: Change of Musical Style or New Concept of Nationality?
Authors: Kleiberg Ståle
Published: August 2009

Slåtter, op. 72, was composed in 1902-3, and is thus among Grieg's very last works. It is also one of his least familiar. ‘Here [in Norway] my early position is still being promoted, praised at every available opportunity at the expense of my current one’, he wrote in his diary on 21 March 1906. Earlier that day he had played six of the 17 slåtter at a concert in Kristiania (now Oslo), and he was disappointed by the lukewarm response. Grieg did, however, live long enough to witness the successful reception of the work, not least in France where avant-garde circles talked about ‘le nouveau Grieg’. Nevertheless, the widespread perception of Grieg - even today - is based on his lyrical pieces, the ‘wheat buns’, as he himself called them. Yet Slåtter is without doubt one of Grieg's most fascinating works. We do indeed meet a ‘new Grieg’ here, and there is good reason to believe that the work played some part in Béla Bartók's development. There was a copy in Bartók's library, and in an article in the Hungarian journal Zeneközlöny from 1911 (a year before he visited Norway) he mentions Norwegian slåtter and Romanian joe as distinctive types of instrumental folk music. According to the Norwegian Grieg scholar Dag Schjelderup-Ebbe, he probably became aware of Grieg's Slåtter in Paris in 1910.
Szymanowski and Narcissism
Authors: Downes Stephen
Published: August 2009

The ‘cultivation of the self’, which Carl E. Schorske has identified as a characteristic of the Viennese bourgeoisie, establishes a ‘link between a devotion to art and a concern with the psyche’. Such a life ‘appropriated the aesthetic, sensuous sensibility’ leading to ‘narcissism and a hypertrophy of the life of feeling’. Szymanowski, who was for many years fascinated by Viennese culture, reflects many of these characteristics. He was, furthermore, greatly influenced by the work of Pater and Wilde, central figures in the English ‘decadent’ scene which, in Arthur Symons's words, was marked by ‘an intense self-consciousness, a restless curiosity in research, an over-subtilizing refinement upon refinement, a spiritual and moral perversity’. It is unsurprising, therefore, to find narcissism appearing as a prominent theme in many of Szymanowski's works.
The Significance of the Concept ‘Image’ in Tippett's Musical Thought: A Perspective from Jung
Authors: Clarke David
Published: August 2009

I know that my true function within a society which embraces all of us, is to continue an age-old tradition…. This tradition is to create images from the depths of the imagination and to give them form whether visual, intellectual or musical For it is only through images that the inner world communicates at all…. Images of vigour for a decadent period, images of calm for one too violent. Images of reconciliation for worlds torn by division. And in an age of mediocrity and shattered dreams, images of abounding, generous, exuberant beauty.
Does Giardia lamblia Cause Villous Atrophy in Children?: A Retrospective Cohort Study of the Histological Abnormalities in Giardiasis
Authors: Koot Bart GP , ten Kate Fiebo JW , Juffrie Mohammad , Rosalina Ina , Taminiau Jan JAM , Benninga Marc A
Published: August 2009

Objective:

To determine the prevalence and type of histological abnormalities in duodenal mucosa associated with Giardia lamblia in children who undergo esophago‐gastroduodenoscopy.

Materials and Methods:

Duodenal biopsies containing G lamblia were retrieved from all paediatric patients who had undergone endoscopy in our centre in the last 20 years. These biopsies were scored for histological abnormalities by a single pathologist using a semiquantative scale and staged according to the Marsh criteria. In those with a Marsh stage above 0, the presence of coeliac disease was investigated.

Results:

After excluding all patients with concomitant coeliac disease, 4 out of 32 (13%) patients had a biopsy showing crypt hyperplasia and 1 out of 32 (3%) had partial villous atrophy. No intraepithelial lymphocytosis was found. In our cohort, 2 patients with giardiasis and mild histological abnormalities were diagnosed with coeliac disease only after a repeated endoscopy and serology were performed; in 1 of them after a delay of 5 years. Other histological abnormalities frequently observed were increased eosinophilic infiltration of the lamina propria (35%) and lymph follicle formation (35%). Infiltration of neutrophilic and eosinophilic granulocytes in the epithelial layer was observed less frequently (16% and 9%, respectively).

Conclusions:

Villous atrophy, intraepithelial lymphocytosis and/or crypt hyperplasia are rare in children with giardiasis who undergo esophagogastroduodenoscopy. Therefore, other causes, particularly coeliac disease, should always be suspected. This study, however, suggests that giardiasis can cause chronic mucosal inflammation, often of an eosinophilic nature, in these children.
Positive Association Between Helicobacter pylori and Gastroesophageal Reflux Disease in Children
Authors: Moon Aeri , Solomon Aliza , Beneck Debra , Cunningham‐Rundles Susanna
Published: August 2009

Objectives:

The role of Helicobacter pylori (H pylori) in gastroesophageal reflux disease (GERD) remains controversial, particularly in children, because there are limited published data. Adult studies suggested that H pylori infection may protect against GERD by causing atrophic gastritis, which leads to reduced gastric acid secretion. The objective of our study was to determine the role of H pylori infection in the development of GERD in a pediatric population.

Patients and Methods:

A retrospective analysis of 420 patients (M:F = 214:206) who underwent esophagogastroduodenoscopy (EGD) with biopsies between January 2000 and April 2006 was conducted. Patient demographics, clinical indications for EGD and the prevalence of reflux esophagitis (RE), the biomarker for GERD, in 2 groups, H pylori positive and H pylori negative, were reviewed. The prevalence of RE in the H pylori–positive and H pylori–negative groups was further analyzed on the basis of sex and age (<1 year, 1–10 years, >10 years). The mean age of the study population was 8.2 years (range 0–20 years). The clinical indications for EGD were as follows: recurrent abdominal pain (n = 186, 44%), malabsorption (n = 80, 19%), persistent vomiting (n = 80, 19%), suspected eosinophilic gastrointestinal disorders (n = 63, 15%), and others such as upper gastrointestinal bleeding or inflammatory bowel disease surveillance (n = 11, 3%). Statistical analysis was performed by using χ2 test, Fisher exact test, and multivariate logistical regression analysis.

Results:

Among the 420 patients, 16 patients (3.8%) were positive for H pylori and 167 patients (39.8%) were found to have RE. Thirteen patients with H pylori were found to have histologic evidence of RE. The prevalence of RE in the H pylori–positive population was 81.3% compared with 38.1% in the H pylori–negative population (P ≤ 0.05). There were no patients with H pylori in the youngest age group. In the second age group (1–10 years), 100% of the H pylori–positive patients had RE, whereas 44.6% of the H pylori–negative patients had RE (P ≤ 0.05). Both male and female patients with H pylori had a higher prevalence of RE, 77.8% and 85.7%, respectively. On a multivariate logistical regression, for the overall study cohort, H pylori–positive patients had an odds ratio of 5.79 of developing RE compared with H pylori–negative patients (P ≤ 0.05).

Conclusions:

Our study results indicate that there is a significantly higher prevalence of RE in an H pylori–infected cohort independent of age or sex. The findings suggest that H pylori infection in children is positively associated with RE.