bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of pudendal nerve anesthetic block using fusion imaging technique in chronic pelvic pain
Authors: Zacchino Michela , Allegri Massimo , Canepari Mario , Minella Cristina E. , Bettinelli Silvia , Draghi Ferdinando , Calliada Fabrizio
Published: October 2010

Chronic perineal pain syndrome caused by pudendal nerve, is caused by the nerve entrapment between the sacrospinous and sacrotuberous ligaments (interligamentous plane) at the ischial spine and in the Alcock's canal. Pain therapists approach the problem with peripheral nerve blocks. Needle placement is done by a fluoroscopic, computed tomography (CT) or ultrasound (US) guide. The first is unable to visualize the interligamentous plane and it exposes the patient to potentially harmful ionizing radiations. CT scan allows the visualization of the interligamentous space and of Alcock's canal, but it is lacking real‐time visual control. US alone ensures real‐time needle advancement and confirmation of injective spread within the interligamentous plane but it's usually combined with intraoperative fluoroscopy because at the depth of the ischial spine (usually more than 7 cm) the resolution should be suboptimal. We tried to improve pudendal anesthetic block using fusion real time imaging between US and CT. The system combines, in real time, US imaging with previous magnetic resonance (MR) or CT data. Imaging fusion is possible through the identification of anatomical landmarks of the same patient obtained by the different imaging modalities. Fusion imaging could help to avoid multiple exposures to ionizing radiations, improving costs and quality. We decided to verify the potential of this technique, normally employed to guide interventional imaging, to peripheral anesthetic block, testing its feasibility.
The contribution of a mobile mental health unit to the promotion of primary mental health in rural areas in Greece: A 2-year follow-up
Authors: Peritogiannis V. , Mantas C. , Alexiou D. , Fotopoulou V. , Mouka V. , Hyphantis T.
Published: October 2010

During the 2 years of the mobile mental-health unit's operation in Northwestern Greece, the referrals increased rapidly with 29.4% of patients never having received mental-health care before, while hospitalizations and relapses reduced significantly, indicating that community-oriented programs can contribute greatly to successfully addressing the needs of patients in remote rural areas.
Labour migration trends and policy challenges in Southeast Asia
Authors: Kaur Amarjit
Published: October 2010

Labour migration in Southeast Asia since the 1970s and 1980s must be understood as an integral part of the post-colonial new geographies of migration. The scope and scale of transnational movements have grown rapidly and major states like Malaysia and Thailand between them currently host about 70 per cent of the estimated 13.5 million migrant workers in the region. Singapore's foreign labour force accounts for 25 per cent of the country's workforce. Two phenomena characterize these labour movements. Like labour-importing Western democracies, the major Southeast Asian labour-importing countries rely on the guest worker program to solve their labour shortage problems. They regulate immigration through elaborate administrative frameworks that are focussed on border control while brokerage firms and labour recruiters carry out recruitment, transportation and placement of migrant workers. These countries’ immigration policies also often provide incentives for skilled workers, boost circular migration flows among low-skilled workers, and include severe penalties for unauthorised migrants. Additionally, comparisons between these countries point to patterns of convergence among them.

This paper explores migration trends in the post-colonial geography of migration against the backdrop of growing regionalism and the development of regional migration systems and migration corridors. It also examines the “new world domestic order” and the development of gendered migration linkages that have resulted in the expansion of the domestic work sector and care-giving migration.
High dietary niacin intake is associated with decreased chromosome translocation frequency in airline pilots
Authors: Yong Lee C. , Petersen Martin R.
Published: October 2010

Experimental studies suggest that B vitamins such as niacin, folate, riboflavin, vitamin B6and vitamin B12may protect against DNA damage induced by ionising radiation (IR). However, to date, data from IR-exposed human populations are not available. We examined the intakes of these B vitamins and their food sources in relation to the frequency of chromosome translocations as a biomarker of cumulative DNA damage, in eighty-two male airline pilots. Dietary intakes were estimated by using a self-administered semi-quantitative FFQ. Translocations in peripheral blood lymphocytes were scored by using fluorescencein situhybridisation whole-chromosome painting. Negative binomial regression was used to estimate rate ratios and 95 % CI, adjusted for age and occupational and lifestyle factors. We observed a significant inverse association between translocation frequency and dietary intake of niacin (P = 0·02): adjusted rate ratio for subjects in the highest tertile compared with the lowest tertile was 0·58 (95 % CI 0·40, 0·83). Translocation frequency was not associated with total niacin intake from food and supplements as well as dietary or total intake of folate, riboflavin or vitamin B6or B12. However, the adjusted rate ratios were significant for subjects with ≥ median compared with < median intake of whole grains (P = 0·03) and red and processed meat (P = 0·01): 0·69 (95 % CI 0·50, 0·96) and 1·56 (95 % CI 1·13, 2·16), respectively. Our data suggest that a high intake of niacin from food or a diet high in whole grains but low in red and processed meat may protect against cumulative DNA damage in IR-exposed persons.
Regulative principles and ‘the Wise Author of Nature’
Authors: PASTERNACK LAWRENCE
Published: October 2010

There is much more said in theCritique of Pure Reasonabout the relationship between God and purposiveness than what is found in Kant's analysis of the physico-theological (design) argument. The ‘Wise Author of Nature’ is central to his analysis of regulative principles in the ‘Appendix to the Transcendental Dialectic’ and also appears in the ‘Canon’, first with regards to the Highest Good and then again in relation to our theoretical use of purposiveness. This paper will begin with a brief discussion of the physico-theological argument before moving on to the Appendix and the Canon. Finally, it will consider some changes to the role of the Wise Author in theCritique of Judgement.
Possible worlds and the beauty of God
Authors: ROBSON MARK IAN THOMAS
Published: October 2010

In this paper I explore the relationship between the idea of possible worlds and the notion of the beauty of God. I argue that there is a clear contradiction between the idea that God is utterly and completely beautiful on the one hand and the notion that He contains within himself all possible worlds on the other. Since some of the possible worlds residing in the mind of the deity are ugly, their presence seems to compromise God's complete and utter beauty.
A minimal volume arithmetic cusped complex hyperbolic orbifold
Authors: ZHAO TIEHONG
Published: October 2010

The sister of Eisenstein–Picard modular group is described explicitly in [10], whose quotient is a noncompact arithmetic complex hyperbolic 2-orbifold of minimal volume (see [16]). We give a construction of a fundamental domain for this group. A presentation of that lattice can be obtained from that construction, which relates to one of Mostow's lattices.
Barriers and triggers to community participation across different stages of conservation management
Authors: RODRÍGUEZ-IZQUIERDO EMILIO , GAVIN MICHAEL C. , MACEDO-BRAVO MIGUEL O.
Published: October 2010

Local community involvement in natural resource management can be critical to conservation success. Community participation in conservation efforts varies widely, reflecting a continuum from protectionist conservation mechanisms to programmes driven by local communities. Conservation is not one event, but an iterative process with many steps (planning, implementation, monitoring) each with an opportunity for different levels of participation. Barriers and triggers to more community involvement in management of the Cordillera Azul National Park (Peru) were examined. Eleven conservation officials and 73 community members provided information on levels of participation achieved at three management stages: Park establishment, management plan development, and management implementation. Park establishment was not a participatory process, owing to the expediency of the conservation agenda and a narrow window of political opportunity. Community involvement increased during the management plan development and its implementation, with communities eager to participate and a public-private partnership introducing new participatory management tools. However, a perceived lack of capacity in terms of community skills, funding availability, time and sufficient conservation personnel, and the definitions of participation used by different stakeholders, limited community involvement in decision-making processes. If conservation is to achieve more effective community involvement, long-term adaptive co-management approaches are needed that clearly define local participation, build capacity of all stakeholders and monitor levels of participation across all stages of project management.
Multiple pathways of inhibition shape bipolar cell responses in the retina
Authors: EGGERS ERIKA D. , LUKASIEWICZ PETER D.
Published: October 2010

Bipolar cells (BCs) are critical relay neurons in the retina that are organized into parallel signaling pathways. The three main signaling pathways in the mammalian retina are the rod, ON cone, and OFF cone BCs. Rod BCs mediate incrementing dim light signals from rods, and ON cone and OFF cone BCs mediate incrementing and decrementing brighter light signals from cones, respectively. The outputs of BCs are shaped by inhibitory inputs from GABAergic and glycinergic amacrine cells in the inner plexiform layer, mediated by three distinct types of inhibitory receptors: GABAA, GABAC, and glycine receptors. The three main BC pathways receive distinct forms of inhibition from these three receptors that shape their light-evoked inhibitory signals. Rod BC inhibition is dominated by slow GABAC receptor inhibition, while OFF cone BCs are dominated by glycinergic inhibition. The inhibitory inputs to BCs are also shaped by serial inhibitory connections between GABAergic amacrine cells that limit the spatial profile of BC inhibition. We discuss our recent studies on how inhibitory inputs to BCs are shaped by receptor expression, receptor properties, and neurotransmitter release properties and how these affect the output of BCs.
Evidence of alpha 7 nicotinic acetylcholine receptor expression in retinal pigment epithelial cells
Authors: MANEU VICTORIA , GERONA GUILLERMO , FERNÁNDEZ LAURA , CUENCA NICOLÁS , LAX PEDRO
Published: October 2010

Some evidence suggests that retinal pigment epithelium (RPE) can express nicotinic acetylcholine receptors (nAChRs) as described for other epithelial cells, where nAChRs have been involved in processes such as cell development, cell death, cell migration, and angiogenesis. This study is designed to determine the expression and activity of α7 nAChRs in RPE cells. Reverse transcriptase (RT)-PCR was performed to test the expression of nicotinic α7 subunit in bovine RPE cells. Protein expression was determined by Western blot and by immunocytochemistry. Expression of nicotinic α7 subunits was also analyzed in cryostat sections of albino rat retina. Changes in protein expression were tested under hypoxic conditions. Functional nAChRs were studied by examining the Ca2+transients elicited by nicotine and acetylcholine stimulation in fura-2–loaded cells. Expression of endogenous modulators of nAChRs was analyzed by RT-PCR and Western blot in retina and RPE. Cultured bovine RPE cells expressed nicotinic receptors containing α7 subunit. RT-PCR amplified the expected specific α7 fragment. Western blotting showed expression at the protein level, with a specific band being found at 57 kDa in both cultured and freshly isolated RPE cells. Expression of nAChRs was confirmed for cultured cells by immunofluorescence. Immunohistochemistry confirmed α7 receptor expression in rat RPE retina. α7 receptor expression was down-regulated by long-term hypoxia. A small subpopulation of RPE cultured cells showed functional nAChRs, as evidenced by the selective response elicited by nicotine and acetylcholine stimulation. Expression of the endogenous nicotinic receptors’ modulator lynx1 was confirmed in bovine retina and RPE, and expression of lynx1 and other endogenous nicotinic receptor modulators (SLURP1 and RGD1308195) were also confirmed in rat retina. These results suggest that nAChRs could have a significant role in RPE, which may not be related to the traditional role in nerve transmission but could more likely be related to the nonneuronal cholinergic system in the eye.
Stepped Care Cognitive Behavioural Therapy for Children with Anxiety Disorders: A New Treatment Approach
Authors: van der Leeden Adelinde J. M. , van Widenfelt Brigit M. , van der Leeden Rien , Liber Juliette M. , Utens Elisabeth M. W. J. , Treffers Philip D. A.
Published: October 2010

Background: The current nonrandomized clinical trial explored changes over time in children with an anxiety disorder during stepped care, manual-based cognitive behaviour therapy (CBT). Methods: Clinically anxious children (8–12 years, n = 133) and their parents participated in child focused CBT (10 sessions). If assessments indicated additional treatment was necessary, participants could step up to a second and possibly third treatment phase (each 5 sessions) including more parental involvement. Results: After the first treatment phase 45% of the Intention-To-Treat sample was free of any anxiety disorder; after the second and third phase an additional 17% and 11% respectively. In total, 74% of the children no longer met criteria for any anxiety disorder following treatment. Child and parent reported anxiety and depression symptoms of children improved significantly during all treatment phases, as well as child reported anxiety sensitivity and negative affect. Children participating in more treatment showed significant improvements during additional treatment phases, indicating that late change occurred for the subgroup that had not changed during the first phase. Conclusions: Stepped care offers a standardized, assessment based, yet tailored treatment approach for children with anxiety disorders. A more intensive treatment is offered when initial CBT is insufficient, providing children additional opportunities to reach the desired outcome.
Sustainable economic development: on the coexistence of resource-dependent and resource-impacting industries
Authors: LÓPEZ RAMÓN
Published: October 2010

This paper studies the interactions between harvesters, whose income depends on a renewable natural resource as a key factor of production (e.g., fisheries) and industries that can have important impacts on the renewable resource, but whose production does not depend on it (e.g., off-shore oil extraction) in the context of a growing economy. We examine these issues for a closed economy focusing on how the co-existence between these two sectors affects sustainable development and the well-being of the poor, i.e., the harvesters. We show that under certain conditions the existence and expansion of a resource-impacting industrial sector may be consistent with sustainable development. However, if these conditions are not met, growth of the resource-impacting sector leads to further resource depletion and may even threaten the feasibility of sustainable development.
Trichotomy and dichotomy results on the complexity of reasoning with disjunctive logic programs
Authors: TRUSZCZYŃSKI MIROSŁAW
Published: October 2010

We present trichotomy results characterizing the complexity of reasoning with disjunctive logic programs. To this end, we introduce a certain definition schema for classes of programs based on a set of allowed arities of rules. We show that each such class of programs has a finite representation, and for each of the classes definable in the schema, we characterize the complexity of the existence of an answer set problem. Next, we derive similar characterizations of the complexity of skeptical and credulous reasoning with disjunctive logic programs. Such results are of potential interest. On the one hand, they reveal some reasons responsible for the hardness of computing answer sets. On the other hand, they identify classes of problem instances, for which the problem is “easy” (in P) or “easier than in general” (in NP). We obtain similar results for the complexity of reasoning with disjunctive programs under the supported-model semantics.
Subcooled critical heat flux: an assessment of the risk to front-end and beamline components of synchrotron light sources
Authors: Brajuskovic B. , Capatina D. , Collins J. , Den Hartog P. , Reneker J.
Published: October 2010

X-ray absorbers in the front ends and beamlines of synchrotron light sources are exposed to very high thermal loads. Many facilities, such as the Advanced Photon Source, are investigating upgrades that will further increase the thermal load. The likelihood of exceeding the limit of subcooled critical heat flux (CHF) in these components was examined. The assessment was performed for both currently possible off-normal operational conditions, such as might occur in the event of a failure of multiple safety interlocks, and the anticipated operating conditions that may result from future upgrades. The subcooled CHF values were calculated using empirical equations frequently cited in the literature and then compared with the computed values of the heat flux at the walls of the component cooling channels in cases where the cooling wall temperature exceeded the water saturation temperature at local hydraulic conditions. Having in mind that the great majority of the available empirical correlations were developed for the conditions characteristic for the operation of heat exchangers in the nuclear power industry, the limitations of this approach are discussed and an experimental study of the subcooled CHF values in the conditions similar to those expected in the front-end and beamline components is proposed.
Simultaneous near‐infrared and visible observations of sprites and acoustic‐gravity waves during the EXL98 campaign
Authors: Siefring Carl L. , Morrill Jeff S. , Sentman Davis D. , Heavner Matthew J.
Published: October 2010

This paper reports the first images of Near‐InfraRed (NIR) 900 to 1700 nm sprite emissions obtained during the Energetics of Upper Atmospheric Excitation by Lightning 1998 (EXL98) airborne observing mission. Results include the first NIR observations of sprites and a correlation between nighttime hydroxyl (OH) airglow, acoustic‐gravity waves, and sprite location. A NIR camera monitored both OH airglow and N2(B) First Positive (1PG) emissions in the NIR by sprites. OH airglow is used as a tracer of acoustic‐gravity waves and density structures in the neutral atmosphere in the 80–95 km altitude region. The visible‐light imager also observed faint hydroxyl airglow, at times, allowing convenient comparison of the gravity waves and the sprites without image processing. On only one night of observations was a clear correlation observed between the OH airglow and the sprites, with tops of extended lines of sprites appearing to align with the acoustic‐gravity wave troughs in the 80 to 95 km altitude region. This investigation shows that a proper viewing geometry is needed to detect such a correlation and requires a distance of about 400–800 km from the sprites. Comparison of sprite visible and NIR emissions show that the NIR is brightest in the central body, likely dimmer at the tops, and rarely above sensitivity in the tendril regions. The observed NIR sprite emissions are thought to be primarily 1PG from the (1,0) and (0,0) vibration transitions near 888 and 1050 nm respectively. The study indicates a need for future NIR spectrographic measurement.
Modeling and simulation of the horizontal component of the geomagnetic field by fractional stochastic differential equations in conjunction with empirical mode decomposition
Authors: Yu Zu‐Guo , Anh Vo , Wang Yang , Mao Dong , Wanliss James
Published: October 2010

In this paper, we investigate the characteristics and develop a stochastic model for the horizontal component Bx of the magnetic field at 22 stations of the global near‐real‐time magnetic observatory network INTERMAGNET. The model is in the form of a fractional stochastic differential equation. A method to estimate the parameters on the basis of observed data and to simulate the data using the model is given. The degree of fractional differentiation and the alpha‐stability exponent of the process are employed to cluster the stations. The Bx time series possess pronounced local trends, which must be removed before modeling and simulation can be performed. This trend removal is carried out by an empirical mode decomposition. An outcome is an efficient method to simulate the Bx time series by empirical mode decomposition and fractional stochastic differential equation. The numerical results indicate the existence of two distinct clusters of the INTERMAGNET: one in the mid‐ and low latitudes consistent with the Dst index, and the other above geomagnetic latitude 60°N consistent with the AE index. This clustering corresponds to the inner magnetosphere and the outer magnetosphere, respectively.
Role of synoptic eddies on low‐frequency precipitation variation
Authors: Kug Jong‐Seong , Jin Fei‐Fei , Ren Hong‐Li
Published: October 2010

This study investigates a contribution of the synoptic‐eddy moisture feedback to low‐frequency precipitation variability. On one hand, synoptic‐eddy moisture flux is systematically controlled by monthly mean flow. On the other hand, anomalous synoptic‐eddy moisture fluxes can positively contribute to low‐frequency precipitation anomalies. The eddy moisture convergence exhibits a considerable magnitude compared to that of precipitation variability, so their ratio is more than 0.5 over several extratropical regions. In addition, the moisture convergence induced by synoptic eddies is significantly correlated to precipitation variability. We also showed eddy‐induced moisture convergence plays an important role in the variability of PNA (Pacific North America Pattern)‐related precipitation and polar precipitation.
Mid‐upper tropospheric methane in the high Northern Hemisphere: Spaceborne observations by AIRS, aircraft measurements, and model simulations
Authors: Xiong Xiaozhen , Barnet Christopher D. , Zhuang Qianlai , Machida Toshinobu , Sweeney Colm , Patra Prabir K.
Published: October 2010

Spaceborne measurements by the Atmospheric Infrared Sounder (AIRS) on the EOS/Aqua satellite provide a global view of the methane (CH4) distribution in the mid‐upper troposphere (MUT‐CH4). The focus of this study is to examine the spatiotemporal variation of MUT‐CH4 in the high Northern Hemisphere (HNH) using AIRS retrievals, aircraft measurements, and simulations from a forward chemistry‐transport model (i.e., ACTM). Data from 2004 and 2005 focusing over two regions (Alaska and Siberia) are analyzed. An important feature in the seasonal variation of CH4 we found is the summer increase of MUT‐CH4, which is nearly opposite to the summer minimum of CH4 in the marine boundary layer (MBL). This study also demonstrated an apparent increase of CH4 over Alaska associated with the 2004 Alaska forest fire and a negative bias of the ACTM simulations in the HNH. The larger bias of the model simulations in the late winter to early spring may indicate possible unidentified CH4 emission sources (e.g., the use of energy or gas leakage) during this period, but more studies will be needed due to the retrieval uncertainties in the polar winter season. The summer increase of MUT‐CH4 is related to surface emission, but the enhanced convection in summer is likely the most important driver.
Map correlation method: Selection of a reference streamgage to estimate daily streamflow at ungaged catchments
Authors: Archfield S. A. , Vogel R. M.
Published: October 2010

Daily streamflow time series are critical to a very broad range of hydrologic problems. Whereas daily streamflow time series are readily obtained from gaged catchments, streamflow information is commonly needed at catchments for which no measured streamflow information exists. At ungaged catchments, methods to estimate daily streamflow time series typically require the use of a reference streamgage, which transfers properties of the streamflow time series at a reference streamgage to the ungaged catchment. Therefore, the selection of a reference streamgage is one of the central challenges associated with estimation of daily streamflow at ungaged basins. The reference streamgage is typically selected by choosing the nearest streamgage; however, this paper shows that selection of the nearest streamgage does not provide a consistent selection criterion. We introduce a new method, termed the map‐correlation method, which selects the reference streamgage whose daily streamflows are most correlated with an ungaged catchment. When applied to the estimation of daily streamflow at 28 streamgages across southern New England, daily streamflows estimated by a reference streamgage selected using the map‐correlation method generally provides improved estimates of daily streamflow time series over streamflows estimated by the selection and use of the nearest streamgage. The map correlation method could have potential for many other applications including identifying redundancy and uniqueness in a streamgage network, calibration of rainfall runoff models at ungaged sites, as well as for use in catchment classification.
Conditional stochastic mapping of transport connectivity
Authors: Fernàndez‐Garcia D. , Trinchero P. , Sanchez‐Vila X.
Published: October 2010

We present a method for the stochastic simulation of point‐to‐point transport connectivity honoring data from three types of information: (1) travel time estimates obtained from field tracer tests; (2) estimates of flow connectivity indicators obtained from the relatively fast or slow flow response that is observed at a point location given the flow impulse at another location, and (3) measurements of transmissivity at a local scale. The method thus efficiently integrates data obtained from different hydraulic tests, each sampling different areas within the aquifer. To achieve this, we first extend the concept of point‐to‐point flow connectivity and transport connectivity, mathematically formulated by Trinchero et al. (2008) for pumping conditions, to support a more general flow configuration. Interestingly, point‐to‐point flow connectivity can be generally seen as a weighted integral of transmissivity over the entire domain, the weighting function being proportional to the sensitivity of heads with respect to the natural log of transmissivity per unit of aquifer volume. On the contrary, point‐to‐point transport connectivity is a weighted integral along the particle path of the solute mass that involves two variables: transmissivity and flow connectivity. Each variable has its own distinct weighting function. The weighting function of transmissivity is inversely proportional to both the homogeneous travel time and the point velocity sampled along the travel path. On this basis, we show how to generate conditional point‐to‐point transport connectivity maps. The method avoids the inference of cross‐covariance functions between variables measured over different scales and sampled areas (which cannot be otherwise estimated with a few data measurements) by expressing them as a function of the local transmissivity covariance function. An example of the method is provided to evaluate the worth of including tracer data to delineate capture zones of abstraction wells originally defined from local transmissivity measurements. Monte Carlo simulations reveal that the impact of including tracer data is a maximum when the travel time data are obtained at a location different than that of transmissivity measurements. The reason is that weighting functions give larger weights to the injection location, so introducing tracer test data at points where transmissivity is already known is somewhat redundant.
Variability in simulated recharge using different GCMs
Authors: Allen D. M. , Cannon A. J. , Toews M. W. , Scibek J.
Published: October 2010

Variations in the prediction of recharge is addressed by comparing recharge simulated using climate data generated using a state‐of‐the‐art downscaling method, TreeGen, with a range of global climate models (GCMs). The study site is the transnational Abbotsford‐Sumas aquifer in coastal British Columbia, Canada and Washington State, USA, and is representative of a wet coastal climate. Sixty‐four recharge zones were defined based on combinations of classed soil permeability, vadose zone permeability, and unsaturated zone depth (or depth to water table) mapped in the study area. One‐dimensional recharge simulations were conducted for each recharge zone using the HELP hydrologic model, which simulates percolation through a vertical column. The HELP model is driven by mean daily temperature, daily precipitation, and daily solar radiation. For the historical recharge simulations, the climate data series was generated using the LARS‐WG stochastic weather generator. Historical recharge was compared to recharge simulated using climate data series derived from the TreeGen downscaling model for three future time periods: 2020s (2010–2039), 2050s (2040–2069), and 2080s (2070–2099) for each of four GCMs (CGCM3.1, ECHAM5, PCM1, and CM2.1). Recharge results are compared on an annual basis for the entire aquifer area. Both increases and decreases relative to historical recharge are simulated depending on time period and model. By the 2080s, the range of model predictions spans −10.5% to +23.2% relative to historical recharge. This variability in recharge predictions suggests that the seasonal performance of the downscaling tool is important and that a range of GCMs should be considered for water management planning.
Observations of long‐duration episodic bottom currents in the Middle America Trench: Evidence for tidally initiated turbidity flows
Authors: Thomson Richard E. , Davis Earl E. , Heesemann Martin , Villinger Heiner
Published: October 2010

Benthic flow in the Middle America Trench off the Pacific coast of Costa Rica is examined using time series from a single‐point acoustic current meter moored 21 m above bottom at 4386 m depth at the southern end of the trench from November 2005 to April 2007. In addition to significant (∼0.1 m s−1) tidal currents, the instrument recorded a series of 12 episodic northwestward along‐trench flow events of roughly monthly duration. Event velocities often exceeded 0.25 m s−1 and were contemporary with enhanced acoustic backscatter intensity. Events ended with a rapid (<1 day) reversal to southeastward flow and reduced backscatter. Seafloor temperature records from two nearby Ocean Drilling Program (ODP) borehole observatory sites reveal that the flow events were accompanied by a steady rise in bottom water temperature. Temperatures dropped abruptly to background values at the end of each event. The event timing generally tracked the envelope of the tidal current modulation. On the basis of the November 2002 to February 2009 borehole observatory temperature records, the events had a mean duration of 40(±20) days and were separated by a between‐event interlude of 30(±25) days. Findings indicate that the episodic flows were likely rotationally modified, autosuspending turbidity currents initiated by tidal current resuspension of sediments above the shoaling trench floor to the southeast of the mooring site. Suspended particles in the turbidity currents are estimated to range from 0.0003% to 0.006% of the current by volume. Results suggest that tidally induced turbidity currents may be common to steep, well‐mixed regions of the deep ocean adjacent to sediment rich continental margins.
Maternal phosphatidylinositol 3‐kinase signalling is crucial for embryonic genome activation and preimplantation embryogenesis
Authors: Zheng Wenjing , Gorre Nagaraju , Shen Yan , Noda Tetsuo , Ogawa Wataru , Lundin Eva , Liu Kui
Published: October 2010

Maternal effect factors derived from oocytes are important for sustaining early embryonic development before the major wave of embryonic genome activation (EGA). In this study, we report a two‐cell‐stage arrest of embryos lacking maternal 3‐phosphoinositide‐dependent protein kinase 1 as a result of suppressed EGA. Concurrent deletion of maternal Pten completely rescued the suppressed EGA and embryonic progression through restored AKT signalling, which fully restored the fertility of double‐mutant females. Our study identifies maternal phosphatidylinositol 3‐kinase signalling as a new maternal effect factor that regulates EGA and preimplantation embryogenesis in mice.
MAPK signalling in cellular metabolism: stress or wellness?
Authors: Gehart Helmuth , Kumpf Susann , Ittner Arne , Ricci Romeo
Published: October 2010

Mitogen‐activated protein kinase (MAPK) signalling occurs in response to almost any change in the extracellular or intracellular milieu that affects the metabolism of the cell, organ or the entire organism. MAPK‐dependent signal transduction is required for physiological metabolic adaptation, but inappropriate MAPK signalling contributes to the development of several interdependent pathological traits, collectively known as metabolic syndrome. Metabolic syndrome leads to life‐threatening clinical consequences, such as type 2 diabetes. This Review provides an overview of the MAPK‐signalling mechanisms that underly basic cellular metabolism, discussing their link to disease.
Characterization of the xenobiotic response ofCaenorhabditis elegansto the anthelmintic drug albendazole and the identification of novel drug glucoside metabolites
Authors: Laing Steven T. , Ivens Al , Laing Roz , Ravikumar Sai , Butler Victoria , Woods Debra J. , Gilleard John S.
Published: October 2010

Knowledge of how anthelmintics are metabolized and excreted in nematodes is an integral part of understanding the factors that determine their potency, spectrum of activity and for investigating mechanisms of resistance. Although there is remarkably little information on these processes in nematodes, it is often suggested that they are of minimal importance for the major anthelmintic drugs. Consequently, we have investigated how the model nematode Caenorhabditis elegans responds to and metabolizes albendazole, one of the most important anthelmintic drugs for human and animal use. Using a mutant strain lacking the β-tubulin drug target to minimize generalized stress responses, we show that the transcriptional response is dominated by genes encoding XMEs (xenobiotic-metabolizing enzymes), particularly cytochrome P450s and UGTs (UDP-glucuronosyl transferases). The most highly induced genes are predominantly expressed in the worm intestine, supporting their role in drug metabolism. HPLC-MS/MS revealed the production of two novel glucoside metabolites in C. elegans identifying a major difference in the biotransformation of this drug between nematodes and mammals. This is the first demonstration of metabolism of a therapeutic anthelmintic in C. elegans and provides a framework for its use to functionally investigate nematode anthelmintic metabolism.
The circadian clock and metabolism
Authors: Froy Oren
Published: October 2010

Mammals have developed an endogenous circadian clock located in the SCN (suprachiasmatic nuclei) of the anterior hypothalamus that responds to the environmental light–dark cycle. Human homoeostatic systems have adapted to daily changes in a way that the body anticipates the sleep and activity periods. Similar clocks have been found in peripheral tissues, such as the liver, intestine and adipose tissue. Recently it has been found that the circadian clock regulates cellular and physiological functions in addition to the expression and/or activity of enzymes and hormones involved in metabolism. In turn, key metabolic enzymes and transcription activators interact with and affect the core clock mechanism. Animals with mutations in clock genes that disrupt cellular rhythmicity have provided evidence to the relationship between the circadian clock and metabolic homoeostasis. The present review will summarize recent findings concerning the relationship between metabolism and circadian rhythms.
Increased Stroop interference with better second-language reading skill
Authors: Braet Wouter , Noppe Nele , Wagemans Johan , Op de Beeck Hans
Published: October 2010

Skilled readers demonstrate remarkable efficiency in processing written words, unlike beginning readers for whom reading occurs more serially and places higher demands on visual attention. In the present study, we used the Stroop paradigm to investigate the relationship between reading skill and automaticity, in individuals learning a second language with a different orthographic system. Prior studies using this paradigm have presented a mixed picture, finding a positive, a negative, or no relationship between the size of Stroop interference and reading skills. Our results show that Stroop interference in the second language was positively related to reading skill (when controlled for interference in the first language). Furthermore, interference was positively related to objective but not subjective indices of the amount of exposure to the second language. We suggest that the lack of consistency in the results of earlier studies may be due, at least in part, to these studies looking at Stroop interference in isolation, rather than comparing interference between languages.
Negative differential resistance in doped poly(3-methylthiophene) devices
Authors: Anjaneyulu P , Sangeeth C S Suchand , Menon Reghu
Published: October 2010

The current density–voltage (J–V) characteristics of poly(3-methylthiophene) devices show a negative differential resistance (NDR) at room temperature with a large peak to valley current ratio (∼507). This NDR can be tuned by two orders of magnitude by controlling the carrier density due to the variation of the space-charge region in the device. The temperature and scan rate dependent J–V measurements infer that the NDR is mainly driven by the trapping and de-trapping of carriers. The photo-generation of carriers is observed to reduce the NDR effect.
The effect of flow cooling on gain and output power of an electrically excited oxygen–iodine laser
Authors: Bruzzese J R , Richards R , Adamovich I V
Published: October 2010

Cooling the flow in the electric discharge excited oxygen–iodine laser is used to increase gain in the supersonic cavity and laser power. The flow is cooled by injecting helium precooled in a liquid nitrogen bath downstream of the iodine injector. The highest gain achieved is 0.21% cm−1 over the gain path of 10 cm. Laser power measured in a stable resonator with 99.9% and 99.0% reflectivity mirrors is 7.8 W. Gain measured downstream of the resonator during lasing remains high, 0.15% cm−1, 25% lower than gain without lasing, demonstrating that a small fraction of power available for lasing is coupled out.
The role of the RF induced electric field in the current drive by EC waves in the presence of magnetic islands
Authors: da S. Rosa P.R. , Ziebell L.F.
Published: October 2010

In this paper we discuss the role played by a radiofrequency induced electric field on the current drive efficiency of electron cyclotron (EC) waves when there are locked or rotating magnetic islands in the plasma. The problem is addressed by numerical solution of the Fokker–Planck equation within the framework of the quasilinear theory incorporating realistic features of the geometry of the magnetic islands. The modes 2/1 and 3/2 are analysed. Our main result is the reduction, although not the complete suppression, of the level of the current driven by the waves in the short time scale needed for the induced field to diffuse away from the islands region. Another finding is the suppression of quasilinear effects on the EC current drive efficiency in the case of locked islands for both 2/1 and 3/2 modes.
Identification and Characterization of a Novel Etiological Agent of Mango Malformation Disease in Mexico, Fusarium mexicanum sp. nov.
Authors: Otero-Colina Gabriel , Rodríguez-Alvarado Gerardo , Fernández-Pavía Sylvia , Maymon Marcel , Ploetz Randy C. , Aoki Takayuki , O'Donnell Kerry , Freeman Stanley
Published: October 2010

The primary objective of this study was to characterize Fusarium spp. associated with the economically devastating mango malformation disease (MMD) in Mexico. In all, 142 Fusarium strains were isolated from symptomatic mango inflorescences and vegetative tissues in eight geographically diverse Mexican states from 2002 through 2007. Initially, all the Mexican isolates were screened for genetic diversity using appolymerase chain reaction and random amplified polymorphic DNA markers and were grouped into seven distinct genotypes. Based on results of these analyses, evolutionary relationships and species limits of the genetically diverse MMD-associated Fusarium spp. were investigated using multilocus DNA sequence data and phylogenetic species recognition. Maximum parsimony analyses of a five-locus data set comprising 5.8 kb of aligned DNA sequence data indicated that at least nine phylogenetically distinct Fusarium spp. within the Gibberella fujikuroi species complex are associated with MMD, including one species within the African clade (Fusarium pseudocircinatum), two species within the Asian clade (F. mangiferae and F. proliferatum), and at least six species within the American clade (F. sterilihyphosum and five undescribed Fusarium spp.). Molecular phylogenetic analyses indicate that a novel genealogically exclusive lineage within the American clade was the predominant MMD associate in Mexico. This new Fusarium sp. caused MMD and could be distinguished from all other known species morphologically by the production of mostly sterile, coiled hyphae which are typically associated with sporodochial conidiophores together with unbranched or sparsely branched aerial conidiophores. Koch's postulates were completed for isolates of the new species on nucellar seedlings of mango cv. Ataulfo. This pathogen is formally described herein as F. mexicanum.
Downward Vascular Translocation of a Green Fluorescent Protein-Tagged Strain of Dickeya sp. (Biovar 3) from Stem and Leaf Inoculation Sites on Potato
Authors: Czajkowski Robert , de Boer Waldo J. , van Veen Johannes A. , van der Wolf Jan M.
Published: October 2010

Translocation of a green fluorescent protein (GFP)-tagged Dickeya sp. from stems or from leaves to underground parts of potato plants was studied in greenhouse experiments. Thirty days after stem inoculation, 90% of plants expressed symptoms at the stem base and 95% of plants showed browning of internal stem tissue. The GFP-tagged Dickeya sp. was detected by dilution plating in extracts of the stem interiors (100%), stem bases (90%), roots (80%), stolons (55%), and progeny tubers (24%). In roots, the GFP-tagged Dickeya sp. was found inside and between parenchyma cells whereas, in stems and stolons, the GFP-tagged Dickeya sp. was found in the xylem vessels and protoxylem cells. In progeny tubers, this strain was detected in the stolon end. Thirty days after leaf inoculation, the GFP-tagged Dickeya sp. was detected in extracts of 75% of the leaves, 88% of the petioles, 63% of the axils, and inside 25% of the stems taken 15 cm above the ground level. UV microscopy confirmed the presence of the GFP-tagged Dickeya sp. inside petioles and in the main leaf veins. No blackleg or aerial stem rot and no translocation of the GFP-tagged Dickeya sp. to underground plant parts was observed. The implications for contamination of progeny tubers are discussed.
Periodicity in Host Availability Does Not Account for Evolutionary Branching as Observed in Many Plant Pathogens: An Application to Gaeumannomyces graminis var. tritici
Authors: van den Berg F. , Gilligan C. A. , Bailey D. J. , van den Bosch F.
Published: October 2010

Periodicity in host availability is common in agricultural systems. Although it is known to have profound effects on plant pathogen abundance, the evolutionary consequences of periodicity for the pathogen population have not previously been analyzed. An epidemiological model incorporating periodic absence of the host crop is combined with the theory of adaptive dynamics to determine whether or not seasonality in host presence plays a role in the occurrence of evolutionary branching, leading to coexisting yet genetically distinct pathogen phenotypes. The study is motivated and illustrated by the specific example of take-all disease of wheat, caused by the pathogen Gaeumannomyces graminis var. tritici, for which two coexisting but genetically distinct types and a trade-off related to seasonality in host presence have been identified. Numerical simulations are used to show that a trade-off between the pathogen transmission rate and the survival of the pathogen between cropping seasons cannot account for the evolutionary branching observed in many pathogens. Model elaborations show that this conclusion holds for a broad range of putative mechanisms. Although the analysis is motivated and illustrated by the specific example of take-all of wheat, the results apply to a broad range of pathogens.
Evolution of the capsular gene locus of Streptococcus pneumoniae serogroup 6
Authors: Bratcher P. E. , Park I. H. , Oliver M. B. , Hortal M. , Camilli R. , Hollingshead S. K. , Camou T. , Nahm M. H.
Published: October 2010

Streptococcus pneumoniae expressing serogroup 6 capsules frequently causes pneumococcal infections and the evolutionary origins of the serogroup 6 strains have been extensively studied. However, these studies were performed when serogroup 6 had only two known members (serotypes 6A and 6B) and before the two new members (serotypes 6C and 6D) expressing wciN

β
were found. We have therefore reinvestigated the evolutionary origins of serogroup 6 by examining the profiles of the capsule gene loci and the multilocus sequence types (MLSTs) of many serogroup 6 isolates from several continents. We confirmed that there are two classes of cps locus sequences for serogroup 6 isolates. In our study, class 2 cps sequences were limited to a few serotype 6B isolates. Neighbour-joining analysis of cps sequence profiles showed a distinct clade for 6C and moderately distinct clades for class 1 6A and 6B sequences. The serotype 6D cps profile was found within the class 1 6B clade, suggesting that it was created by recombination between 6C and 6B cps loci. Interestingly, all 6C isolates also had a unique wzy allele with a 6 bp deletion. This suggests that serotype switching to 6C involves the transfer of a large (>4 kb) gene segment that includes both the wciN

β
allele and the ‘short’ wzy allele. The MLST studies of serotype 6C isolates suggest that the 6C cps locus is incorporated into many different pneumococcal genomic backgrounds but that, interestingly, 6C cps may have preferentially entered strains of the same genomic backgrounds as those of serotype 6A.