bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing agroecosystems: Effects of cropping and tillage patterns on soil, water, energy use and productivity
Authors: Gregory Megan M. , Shea Kathleen L. , Bakko Eugene B.
Published: November 2010

We compared soil characteristics, runoff water quantity and nutrient fluxes, energy use and productivity of three farm types in an unusually dry farming season: conventional (continuous corn and deep tillage), rotation (5-year corn–soybean–oats/alfalfa–alfalfa–alfalfa rotation with tillage 2/5 years) and no-till (corn–soybean with no cultivation). Soil organic matter content was highest on the rotation farm, followed by the no-till farm, and lowest on the conventional farm. Nitrate content of the soil did not differ significantly among the three farms, although the conventional farm had a much higher input of fertilizer nitrogen. Soil penetrometer resistance was lower and percent soil moisture was higher in the no-till and rotation systems compared to the conventional farm. Soil macroinvertebrate abundance and diversity were highest on the no-till farm, followed by the rotation farm. No invertebrates were found in the soil of the conventional farm. The conventional farm had the highest runoff volume per cm rain and higher nitrogen (N) loss in runoff when compared to the rotation and no-till farms, as well as a higher phosphorus (P) flux in comparison to the no-till farm. These results indicate that perennial close-seeded crops (such as alfalfa) used in crop rotations, as well as plant residue left on the surface of no-till fields, can enhance soil organic content and decrease runoff. The lower soil penetrometer resistance and higher soil moisture on the rotation and no-till farms show that conservation tillage can increase soil aggregation and water infiltration, both of which prevent erosion. Furthermore, crop rotation, and particularly no-till, promote diverse invertebrate populations, which play an important role in maintaining nutrient cycling and soil structure. Crop rotation and no-till agriculture are less fossil-fuel intensive than conventional agriculture, due to decreased use of fertilizers, pesticides and fuel. In this unusually dry year they provided superior corn and soybean yields, most likely due to higher soil moisture as a result of greater water infiltration and retention associated with cover crops (rotation farm) and crop residue (no-till farm).
Chemical changes under aerobic composting and nutrient supplying potential of banana residue compost
Authors: Ultra Venecio U. , Mendoza Danilo M. , Briones Angelina M.
Published: November 2010

In anticipation of the Philippines being a major producer of organic bananas, this study was conducted to provide a quantitative basis for certain practices in organic farming. The nutrient supplying capacity of banana residues in combination with leguminous materials and chicken manure was investigated in composting studies. Changes in the chemical composition of ten formulations of banana residue-based compost involving leguminous plants (Sesbania rostrata, Flemingia macrophylla, Arachis hypogea) and chicken manure were analyzed periodically during a composting period of 16 weeks. Results showed that combinations of banana residues (BnR) and chicken manure or leguminous plants were highly decomposed compared to untreated BnR. The use of leguminous plants and/or chicken manure enhanced the composting process significantly compared to the effect of Bioquick. The compost piles were characterized by increases in pH, total N and total P, and decreases in total K, total carbon and C/N ratio with time. Notably, BnR+chicken manure attained a C/N ratio of 15 at 4 weeks, while the BnR+leguminous materials reached such a low C/N ratio at 8–16 weeks. An incubation study was conducted under greenhouse conditions for 24 weeks. It was designed to follow the dynamics of nitrogen (N), phosphorus (P) and potassium (K) availability in two clay soils (Antipolo and Lipa) amended with five compost formulations (BnR alone, BnR+Sesbania prunings, BnR+Flemingia prunings, BnR+peanut stover and BnR+chicken manure) and with uncomposted banana residue at an application rate of 20 Mg ha−1. Results showed that net N mineralization occurred in soils amended with BnR+chicken manure and BnR+leguminous materials, which had C/N ratios ranging from 12 to 16. Net N immobilization during the earlier period of incubation was observed in uncomposted and composted banana residues with a C/N ratio of 68 and 24, respectively. Significantly higher net P mineralization was obtained only in soils amended with BnR+chicken manure. An abrupt increase in exchangeable K was observed in all treatments 2 weeks after the incorporation of organic residues. Higher available K in pure BnR treatments (uncomposted or composted) exhibits the inherently high K content of banana residues.
Clustered Randomized Controlled Trial of a Hand Hygiene Intervention Involving Pocket-Sized Containers of Alcohol-Based Hand Rub for the Control of Infections in Long-Term Care Facilities
Authors: Yeung Wing Kin , Tam Wai San Wilson , Wong Tze Wai
Published: November 2010

Objective.

To investigate the effectiveness of a multifaceted hand hygiene program involving the use of pocket-sized containers of antiseptic gel in long-term care facilities (LTCFs) with elderly residents.

Methods.

In this clustered randomized controlled trial, Hong Kong LTCFs for elderly persons were recruited via snowball sampling. Staff hand hygiene adherence was directly observed, and residents' infections necessitating hospitalization were recorded. After a 3-month preintervention period, LTCFs were randomized to receive pocket-sized containers of alcohol-based gel, reminder materials, and education for all HCWs (treatment group) or to receive basic life support education and workshops for all healthcare workers (HCWs) (control group). A 2-week intervention period (April 1-15, 2007) was followed by 7 months of postintervention observations.

Results.

In the 3 treatment LTCFs, adherence to hand rubbing increased from 5 (1.5%) of 333 to 233 (15.9%) of 1,465 hand hygiene opportunities (P = .001) and total hand hygiene adherence increased from 86 (25.8%) of 333 to 488 (33.3%) of 1,465 opportunities (P = .01) after intervention; the 3 control LTCFs showed no significant change. In the treatment group, the incidence of serious infections decreased from 31 cases in 21,862 resident-days (1.42 cases per 1,000 resident-days) to 33 cases in 50,441 resident-days (0.65 cases per 1,000 resident-days) (P = .002), whereas in the control group, it increased from 16 cases in 32,726 resident-days (0.49 cases per 1,000 resident-days) to 85 cases in 81,177 resident-days (1.05 cases per 1,000 resident-days) (P = .004). In the treatment group, the incidence of pneumonia decreased from 0.91 to 0.28 cases per 1,000 resident-days (P = .001) and the death rate due to infection decreased from 0.37 to 0.10 deaths per 1,000 resident-days (P = .01); the control group revealed no significant change.

Conclusions.

A hand hygiene program involving the use of pocket-sized containers of antiseptic gel and education could effectively increase adherence to hand rubbing and reduce the incidence of serious infections in LTCFs with elderly residents.
Hospital Capacity during an Influenza Pandemic—Buenos Aires, Argentina, 2009
Authors: Meites Elissa , Farias Daniel , Raffo Lucrecia , Albalak Rachel , Carlino Oreste Luis , McDonald L. Clifford , Widdowson Marc-Alain
Published: November 2010

At a major referral hospital in the Southern Hemisphere, the 2009 influenza A (H1N1) pandemic brought increased critical care demand and more unscheduled nursing absences. Because of careful preparedness planning, including rapid expansion and redistribution of the numbers of available beds and staff, hospital surge capacity was not exceeded.
ISOLATED WOLF–RAYET STARS AND O SUPERGIANTS IN THE GALACTIC CENTER REGION IDENTIFIED VIA PASCHEN-α EXCESS
Authors: Mauerhan J. C. , Cotera A. , Dong H. , Morris M. R. , Wang Q. D. , Stolovy S. R. , Lang C.
Published: November 2010

We report the discovery of 19 hot, evolved, massive stars near the Galactic center region (GCR). These objects were selected for spectroscopy owing to their detection as strong sources of Paschen-α (Pα) emission-line excess, following a narrowband imaging survey of the central 0.°65 × 0.°25 (l, b) around Sgr A* with the Hubble Space Telescope. Discoveries include six carbon-type (WC) and five nitrogen-type (WN) Wolf–Rayet stars, six O supergiants, and two B supergiants. Two of the O supergiants have X-ray counterparts having properties consistent with solitary O stars and colliding-wind binaries. The infrared photometry of 17 stars is consistent with the Galactic center distance, but 2 of them are located in the foreground. Several WC stars exhibit a relatively large infrared excess, which is possibly thermal emission from hot dust. Most of the stars appear scattered throughout the GCR, with no relation to the three known massive young clusters; several others lie near the Arches and Quintuplet clusters and may have originated within one of these systems. The results of this work bring the total sample of Wolf–Rayet (WR) stars in the GCR to 88. All sources of strong Pα excess have been identified in the area surveyed with HST, which implies that the sample of WN stars in this region is near completion, and is dominated by late (WNL) types. The current WC sample, although probably not complete, is almost exclusively dominated by late (WCL) types. The observed WR subtype distribution in the GCR is a reflection of the intrinsic rarity of early subtypes (WNE and WCE) in the inner Galaxy, an effect that is driven by metallicity.
Deformations of the modular group as a quasifuchsian correspondence
Authors: Bullett Shaun
Published: November 2010

When viewed as a

(
2
:
2
)

(2:2)

holomorphic correspondence on the Riemann sphere, the modular group

P
S

L
2

(

Z

)

PSL_2({\mathbb Z})

has a moduli space

Q

{\mathcal Q}

of non-trivial deformations for which the limit set remains a topological circle. This space is analogous to a Bers slice of the deformation space of a Fuchsian group as a Kleinian group, but there are certain differences. A Bers slice contains a single quasiconformal conjugacy class of Kleinian groups: we show that for an open dense set of parameter values in

Q

{\mathcal Q}

the correspondence belongs to a single quasi-conformal conjugacy class, but that at a countable set

C

{\mathcal C}

of isolated parameter values it satisfies an additional critical relation. We classify these relations, propose ‘pleating coordinates’ for

Q

{\mathcal Q}

, and investigate how the correspondence degenerates on the boundary of

Q

{\mathcal Q}

. In particular, we show that there is a point on the boundary of

Q

{\mathcal Q}

where the correspondence degenerates into a mating between

P
S

L
2

(

Z

)

PSL_2(\mathbb Z)

and the quadratic polynomial

z
→

z
2

+
1

/

4

z \to z^2+1/4

. A key ingredient in our analysis is a bijection between

Q

∖

C

{\mathcal Q}\setminus {\mathcal C}

and an intermediate cover between the moduli space of the space of non-critical grand orbits of the correspondence, and its universal cover, the corresponding Teichmüller space.
Specific, non-nutritional association between an ascomycete fungus and
Allomerus
plant-ants
Authors: Ruiz-González Mario X. , Malé Pierre-Jean G. , Leroy Céline , Dejean Alain , Gryta Hervé , Jargeat Patricia , Quilichini Angélique , Orivel Jérôme
Published: November 2010

Ant–fungus associations are well known from attine ants, whose nutrition is based on a symbiosis with basidiomycete fungi. Otherwise, only a few non-nutritional ant–fungus associations have been recorded to date. Here we focus on one of these associations involving
Allomerus
plant-ants that build galleried structures on their myrmecophytic hosts in order to ambush prey. We show that this association is not opportunistic because the ants select from a monophyletic group of closely related fungal haplotypes of an ascomycete species from the order Chaetothyriales that consistently grows on and has been isolated from the galleries. Both the ants' behaviour and an analysis of the genetic population structure of the ants and the fungus argue for host specificity in this interaction. The ants' behaviour reveals a major investment in manipulating, growing and cleaning the fungus. A molecular analysis of the fungus demonstrates the widespread occurrence of one haplotype and many other haplotypes with a lower occurrence, as well as significant variation in the presence of these fungal haplotypes between areas and ant species. Altogether, these results suggest that such an interaction might represent an as-yet undescribed type of specific association between ants and fungus in which the ants cultivate fungal mycelia to strengthen their hunting galleries.
Differential outcomes of unilateral interferences at birth
Authors: de Boyer des Roches Alice , Durier Virginie , Richard-Yris Marie-Annick , Blois-Heulin Catherine , Ezzaouïa Mohammed , Hausberger Martine , Henry Severine
Published: November 2010

Behavioural modifications, including modifications of emotional reactivity, can occur following early experience such as handling (manual rubbing). Here, we investigated the effects of unilateral tactile stimulation at an early stage on emotional reactions later on. We handled newborn foals intensively on one side of their body. This early unilateral tactile experience had medium-term effects: the reactions of foals to a human approach, when they were 10 days old, differed according to the side stimulated at birth. Fewer right-handled foals accepted contact with humans, they delayed first contact longer and they evaded approaching humans sooner than did non-handled and left-handled foals. These results raise questions concerning the organization of neonatal care in animals and humans.
Parameterizing state–space models for infectious disease dynamics by generalized profiling: measles in Ontario
Authors: Hooker Giles , Ellner Stephen P. , Roditi Laura De Vargas , Earn David J. D.
Published: November 2010

Parameter estimation for infectious disease models is important for basic understanding (e.g. to identify major transmission pathways), for forecasting emerging epidemics, and for designing control measures. Differential equation models are often used, but statistical inference for differential equations suffers from numerical challenges and poor agreement between observational data and deterministic models. Accounting for these departures via stochastic model terms requires full specification of the probabilistic dynamics, and computationally demanding estimation methods. Here, we demonstrate the utility of an alternative approach, generalized profiling, which provides robustness to violations of a deterministic model without needing to specify a complete probabilistic model. We introduce novel means for estimating the robustness parameters and for statistical inference in this framework. The methods are applied to a model for pre-vaccination measles incidence in Ontario, and we demonstrate the statistical validity of our inference through extensive simulation. The results confirm that school term versus summer drives seasonality of transmission, but we find no effects of short school breaks and the estimated basic reproductive ratioℛ0greatly exceeds previous estimates. The approach applies naturally to any system for which candidate differential equations are available, and avoids many challenges that have limited Monte Carlo inference for state–space models.
Nonlinear speech analysis algorithms mapped to a standard metric achieve clinically useful quantification of average Parkinson's disease symptom severity
Authors: Tsanas Athanasios , Little Max A. , McSharry Patrick E. , Ramig Lorraine O.
Published: November 2010

The standard reference clinical score quantifying average Parkinson's disease (PD) symptom severity is the Unified Parkinson's Disease Rating Scale (UPDRS). At present, UPDRS is determined by the subjective clinical evaluation of the patient's ability to adequately cope with a range of tasks. In this study, we extend recent findings that UPDRS can be objectively assessed to clinically useful accuracy using simple, self-administered speech tests, without requiring the patient's physical presence in the clinic. We apply a wide range of known speech signal processing algorithms to a large database (approx. 6000 recordings from 42 PD patients, recruited to a six-month, multi-centre trial) and propose a number of novel, nonlinear signal processing algorithms which reveal pathological characteristics in PD more accurately than existing approaches. Robust feature selection algorithms select the optimal subset of these algorithms, which is fed into non-parametric regression and classification algorithms, mapping the signal processing algorithm outputs to UPDRS. We demonstrate rapid, accurate replication of the UPDRS assessment with clinically useful accuracy (about 2 UPDRS points difference from the clinicians' estimates,p< 0.001). This study supports the viability of frequent, remote, cost-effective, objective, accurate UPDRS telemonitoring based on self-administered speech tests. This technology could facilitate large-scale clinical trials into novel PD treatments.
Escherichia coliO157 infection on Scottish cattle farms: dynamics and control
Authors: Zhang Xu-Sheng , Woolhouse Mark E. J.
Published: November 2010

In this study, we parametrize a stochastic individual-based model of the transmission dynamics ofEscherichia coliO157 infection among Scottish cattle farms and use the model to predict the impacts of both targeted and non-targeted interventions. We first generate distributions of model parameter estimates using Markov chain Monte Carlo methods. Despite considerable uncertainty in parameter values, each set of parameter values within the 95th percentile range implies a fairly similar impact of interventions. Interventions that reduce the transmission coefficient and/or increase the recovery rate of infected farms (e.g. via vaccination and biosecurity) are much more effective in reducing the level of infection than reducing cattle movement rates, which improves effectiveness only when the overall control effort is small. Targeted interventions based on farm-level risk factors are more efficient than non-targeted interventions. Herd size is a major determinant of risk of infection, and our simulations confirmed that targeting interventions at farms with the largest herds is almost as effective as targeting based on overall risk. However, because of the striking characteristic that the infection force depends weakly on the number of infected farms, no interventions that are less than 100 per cent effective can eradicateE. coliO157 infection from Scottish cattle farms, implying that eliminating the disease is impractical.
The importance of structured noise in the generation of self-organizing tissue patterns through contact-mediated cell–cell signalling
Authors: Cohen Michael , Baum Buzz , Miodownik Mark
Published: November 2010

Lateral inhibition provides the basis for a self-organizing patterning system in which distinct cell states emerge from an otherwise uniform field of cells. The development of the microchaete bristle pattern on the notum of the fruitfly,Drosophila melanogaster, has long served as a popular model of this process. We recently showed that this bristle pattern depends upon a population of dynamic, basal actin-based filopodia, which span multiple cell diameters. These protrusions establish transient signalling contacts between non-neighbouring cells, generating a type of structured noise that helps to yield a well-ordered and spaced pattern of bristles. Here, we develop a general model of protrusion-based patterning to analyse the role of noise in this process. Using a simple asynchronous cellular automata rule-based model we show that this type of structured noise drives the gradual refinement of lateral inhibition-mediated patterning, as the system moves towards a stable configuration in which cells expressing the inhibitory signal are near-optimally packed. By analysing the effects of introducing thresholds required for signal detection in this model of lateral inhibition, our study shows how filopodia-mediated cell–cell communication can generate complex patterns of spots and stripes, which, in the presence of signalling noise, align themselves across a patterning field. Thus, intermittent protrusion-based signalling has the potential to yield robust self-organizing tissue-wide patterns without the need to invoke diffusion-mediated signalling.
Retrieval of phytoplankton size from bio-optical measurements: theory and applications
Authors: Roy Shovonlal , Sathyendranath Shubha , Platt Trevor
Published: November 2010

The absorption coefficient of a substance distributed as discrete particles in suspension is less than that of the same material dissolved uniformly in a medium—a phenomenon commonly referred to as the flattening effect. The decrease in the absorption coefficient owing to flattening effect depends on the concentration of the absorbing pigment inside the particle, the specific absorption coefficient of the pigment within the particle, and on the diameter of the particle, if the particles are assumed to be spherical. For phytoplankton cells in the ocean, with diameters ranging from less than 1 µm to more than 100 µm, the flattening effect is variable, and sometimes pronounced, as has been well documented in the literature. Here, we demonstrate how the
in vivo
absorption coefficient of phytoplankton cells per unit concentration of its major pigment, chlorophyll
a
, can be used to determine the average cell size of the phytoplankton population. Sensitivity analyses are carried out to evaluate the errors in the estimated diameter owing to potential errors in the model assumptions. Cell sizes computed for field samples using the model are compared qualitatively with indirect estimates of size classes derived from high performance liquid chromatography data. Also, the results are compared quantitatively against measurements of cell size in laboratory cultures. The method developed is easy-to-apply as an operational tool for
in situ
observations, and has the potential for application to remote sensing of ocean colour data.
Indoor residual spray and insecticide-treated bednets for malaria control: theoretical synergisms and antagonisms
Authors: Yakob Laith , Dunning Rebecca , Yan Guiyun
Published: November 2010

Indoor residual spray (IRS) of insecticides and insecticide-treated bednets (ITNs) are the two most important malaria vector control tools in the tropical world. Application of both tools in the same locations is being implemented for malaria control in endemic and epidemic Africa. The two tools are assumed to have synergistic benefits in reducing malaria transmission because they both act at multiple stages of the transmission cycle. However, this assumption has not been rigorously examined, empirically or theoretically. Using mathematical modelling, we obtained the conditions for which a combination strategy can be expected to improve upon single control tools. Specifically, spraying of dichlorodiphenyltrichloroethane (DDT) in all houses where residents are not using ITNs can reduce transmission of malaria (
R
0
) by up to 10 times more than the reduction achieved through ITNs alone. Importantly, however, we also show how antagonism between control tools can arise via interference of their modes of action. Repellent IRS reduces the likelihood that ITNs are contacted within sprayed houses and ITNs reduce the rate at which blood-fed mosquitoes rest on sprayed walls. For example, 80 per cent coverage of ITNs and DDT used together at the household level resulted in an
R
0
of 11.1 when compared with an
R
0
of 0.1 achieved with 80 per cent ITN coverage without DDT. While this undesired effect can be avoided using low-repellence pyrethroid chemicals for IRS, the extent of the potential benefits is also attenuated. We discuss the impact that this result will likely have on future efforts in malaria control combination strategy.
A Mars hopping vehicle propelled by a radioisotope thermal rocket: thermofluid design and materials selection
Authors: Williams H. R. , Ambrosi R. M. , Bannister N. P.
Published: November 2010

Rocket-propelled vehicles capable of travelling a kilometre or more in a ballistic ‘hop’ with propellants acquired from the Martian atmosphere offer the potential for increased mobility and planetary science return compared with conventional rovers. In concept, a radioisotope heat source heats a core or ‘thermal capacitor’, which in turn heats propellant exhausted through a rocket nozzle to provide thrust. A systematic study of the thermodynamics, heat transfer and selection of core materials for a Mars hopper was undertaken. The aim was to advance the motor design and assess technical risks and feasibility. Analytical and numerical motor models were developed; the former to generate thermodynamic performance limits, an ideal hop distance and plot a materials selection chart using simple explicit relations. The numerical model assessed the effect of core configuration and geometry. A hop coefficientChopis shown to characterize the effect of core geometry independently of core material and temperature. The target hop distance of 1 km is shown to be robust. A moderate advantage to pebble-bed cores over a core consisting of straight channels was suggested. High-performance engineering ceramics such as boron carbide offer the longest hop providing the core temperature can be increased significantly above 1200 K.
Anisotropy of the static dipole polarizability induced by the spin–orbit interaction: the S-state atoms N–Bi, Cr, Mo and Re
Authors: Buchachenko Alexei A.
Published: November 2010

A systematic
ab initio
study is performed on the ground state static dipole polarizabilities of the

2
S
+1

S,
S
>1/2, atoms from N to Bi, Cr, Mo, Mn, Tc and Re. The benchmark scalar-relativistic values of the scalar polarizability components are obtained using the coupled cluster method. The spin–orbit configuration interaction calculations are carried out for the anisotropic (tensor) polarizability components of these atoms (except Mn and Tc) that arise from the second-order spin–orbit interaction. The tensor polarizabilities are calculated for the first time and found to increase from 10
−5
(N) to 3.8 atomic units (Bi) approximately as the fourth power of the nuclear charge. The simple correlations and implication to magnetic trapping of cold atoms are discussed.
Antipodean white sharks on a Mediterranean walkabout? Historical dispersal leads to genetic discontinuity and an endangered anomalous population
Authors: Gubili Chrysoula , Bilgin Raşit , Kalkan Evrim , Karhan S. Ünsal , Jones Catherine S. , Sims David W. , Kabasakal Hakan , Martin Andrew P. , Noble Leslie R.
Published: November 2010

The provenance of white sharks (
Carcharodon carcharias
) in the Mediterranean is both a conundrum and an important conservation issue. Considering this species's propensity for natal philopatry, any evidence that the Mediterranean stock has little or no contemporary immigration from the Atlantic would suggest that it is extraordinarily vulnerable. To address this issue we sequenced the mitochondrial control region of four rare Mediterranean white sharks. Unexpectedly, the juvenile sequences were identical although collected at different locations and times, showing little genetic differentiation from Indo-Pacific lineages, but strong separation from geographically closer Atlantic/western Indian Ocean haplotypes. Historical long-distance dispersal (probably a consequence of navigational error during past climatic oscillations) and potential founder effects are invoked to explain the anomalous relationships of this isolated ‘sink’ population, highlighting the present vulnerability of its nursery grounds.
Phenotypic convergence along a gradient of predation risk
Authors: Dennis S. R. , Carter Mauricio J. , Hentley W. T. , Beckerman A. P.
Published: November 2010

A long-standing question in ecology is whether phenotypic plasticity, rather than selectionper se, is responsible for phenotypic variation among populations. Plasticity can increase or decrease variation, but most previous studies have been limited to single populations, single traits and a small number of environments assessed using univariate reaction norms. Here, examining two genetically distinct populations ofDaphnia pulexwith different predation histories, we quantified predator-induced plasticity among 11 traits along a fine-scale gradient of predation risk by a predator (Chaoborus) common to both populations. We test the hypothesis that plasticity can be responsible for convergence in phenotypes among different populations by experimentally characterizing multivariate reaction norms with phenotypic trajectory analysis (PTA). Univariate analyses showed that all genotypes increased age and size at maturity, and invested in defensive spikes (neckteeth), but failed to quantitatively describe whole-organism response. In contrast, PTA quantified and qualified the phenotypic strategy the organism mobilized against the selection pressure. We demonstrate, at the whole-organism level, that the two populations occupy different areas of phenotypic space in the absence of predation but converge in phenotypic space as predation threat increases.
From the first intention movement to the last joiner: macaques combine mimetic rules to optimize their collective decisions
Authors: Sueur C. , Deneubourg J. L. , Petit O.
Published: November 2010

Mechanisms related to collective decision making have recently been found in almost all animal reigns from amoebae to worms, insects and vertebrates, including human beings. Decision-making mechanisms related to collective movements—including pre-departure and joining—have already been studied at different steps of the movement process, but these studies were always carried out separately. We therefore have no understanding of how these different processes are related when they underlie the same collective decision-making event. Here, we consider the whole departure process of two groups of Tonkean macaques (Macaca tonkeana), using a stochastic model. When several exclusive choices are proposed, macaques vote and choose the majority. Individuals then join the movement according to a mimetism based on affiliative relationships. The pre-departure quorum and the joining mimetic mechanism are probably linked, but we have not yet identified which transition mechanism is used. This study shows that decision-making related to macaque group movements is governed by a quorum rule combined with a selective mimetism at departure. This is the first time that transition mechanisms have been described in mammals, which consequently helps understand how a voting process leads to social amplification. Our study also provides the first complete proof that there is continuity in the decision-making processes underlying collective movements in mammals from the first intention movement right through to the last joiner.
Copy number variation modifies expression time courses
Authors: Chaignat Evelyne , Yahya-Graison Emilie Aït , Henrichsen Charlotte N. , Chrast Jacqueline , Schütz Frédéric , Pradervand Sylvain , Reymond Alexandre
Published: November 2010

A preliminary understanding into the phenotypic effect of DNA segment copy number variation (CNV) is emerging. These rearrangements were demonstrated to influence, in a somewhat dose-dependent manner, the expression of genes that map within them. They were also shown to modify the expression of genes located on their flanks and sometimes those at a great distance from their boundary. Here we demonstrate, by monitoring these effects at multiple life stages, that these controls over expression are effective throughout mouse development. Similarly, we observe that the more specific spatial expression patterns of CNV genes are maintained through life. However, we find that some brain-expressed genes mapping within CNVs appear to be under compensatory loops only at specific time points, indicating that the effect of CNVs on these genes is modulated during development. Notably, we also observe that CNV genes are significantly enriched within transcripts that show variable time courses of expression between strains. Thus, modifying the copy number of a gene may potentially alter not only its expression level, but also the timing of its expression.
Testing of the Superconducting Magnet and Cryogenics for the AMS-02 Experiment
Authors: McIntyre Peter
Published: November 2010

The superconducting magnet, cryogenics, and detector systems of the AMS experiment was fully integrated and tested in test beam at CERN during 2009. In Spring 2010 the experiment underwent thermal vacuum tests at ESTEC, where it was operated in conditions simulating those that will pertain in orbit. All elements of the superconducting magnet and cryogenics performed as designed, and equilibrium operation was attained at several values of vacuum case temperature. Details of the tests are presented. A thermal model of the overall cryogenic system was calibrated from those measurements. The model was used to predict the cryogenic lifetime of the experiment, as it would be staged on ISS, to be (28 ± 6) months.
Evaluating foreland basin partitioning in the northern Andes using Cenozoic fill of the Floresta basin, Eastern Cordillera, Colombia
Authors: Saylor Joel E. , Horton Brian K. , Nie Junsheng , Corredor Jaime , Mora Andrés
Published: November 2010

This paper addresses foreland basin fragmentation through integrated detrital zircon U–Pb geochronology, sandstone petrography, facies analysis and palaeocurrent measurements from a Mesozoic–Cenozoic clastic succession preserved in the northern Andean retroarc fold‐thrust belt. Situated along the axis of the Eastern Cordillera of Colombia, the Floresta basin first received sediment from the eastern craton (Guyana shield) in the Cretaceous–early Palaeocene and then from the western magmatic arc (Central Cordillera) starting in the mid‐Palaeocene. The upper‐crustal magmatic arc was replaced by a metamorphic basement source in the middle Eocene. This, in turn, was replaced by an upper‐crustal fold‐thrust belt source in the late Eocene which persisted until Oligocene truncation of the Cenozoic section by the eastward advancing thrust front. Sedimentary facies analysis indicates minimal changes in depositional environments from shallow marine to low‐gradient fluvial and estuarine deposits. These same environments are recorded in coeval strata across the Eastern Cordillera. Throughout the Palaeogene, palaeocurrent and sediment provenance data point to a uniform western or southwestern sediment source. These data show that the Floresta basin existed as part of a laterally extensive, unbroken foreland basin connected with the proximal western (Magdalena Valley) basin from mid‐Paleocene to late Eocene time when it was isolated by uplift of the western flank of the Eastern Cordillera. The Floresta basin was also connected with the distal eastern (Llanos) basin from the Cretaceous until its late Oligocene truncation by the advancing thrust front.
Mitoxantrone in combination with an inhibitor of DNA‐dependent protein kinase: a potential therapy for high risk B‐cell chronic lymphocytic leukaemia
Authors: Elliott Sarah L. , Crawford Clark , Mulligan Evan , Summerfield Geoffrey , Newton Paula , Wallis Jonathan , Mainou‐Fowler Tryfonia , Evans Paul , Bedwell Clare , Durkacz Barbara W. , Willmore Elaine
Published: November 2010

Defects in the DNA damage response pathway [e.g. del(17p)] are associated with drug‐resistant B‐cell chronic lymphocytic leukaemia (CLL). We previously demonstrated that over‐expression of DNA‐dependent protein kinase (DNA‐PK) correlates with chemo‐resistance and that inhibition of DNA‐PK sensitizes CLL cells to chemotherapeutics. Here, we investigated expression of DNA‐PK and other proteins that impact on drug resistance, and evaluated the effects of a DNA‐PK inhibitor (NU7441) on mitoxantrone‐induced cytotoxicity in CLL cells. NU7441 sensitized cells from 42/49 CLL samples to mitoxantrone, with sensitization ranging from 2‐ to 200‐fold Co‐culture of CLL cells in conditioned stromal medium increased chemoresistance but did not reduce sensitization by NU7441. Mitoxantrone treatment induced γH2AX foci and NU7441 increased their longevity (24 h). NU7441 prevented mitoxantrone‐induced autophosphorylation of the DNA‐PK catalytic subunit (DNA‐PKcs) at Ser 2056, confirming that DNA‐PK participates in repair of mitoxantrone‐induced DNA damage. del(17p) cases were more resistant to mitoxantrone than del(13q) cases, but were resensitized (7–16 fold) by co‐incubation with NU7441. Expression of DNA‐PKcs, Ku80, P‐glycoprotein and topoisomerase IIβ were significantly higher in del(17p) cases. PRKDC mRNA levels correlated with DNA‐PKcs protein expression, which predicted shorter survival. These data confirm the potential of DNA‐PK as a therapeutic target in poor prognosis CLL.
Clinical evaluation of the European LeukaemiaNet criteria for clinicohaematological response and resistance/intolerance to hydroxycarbamide in essential thrombocythaemia
Authors: Hernández‐Boluda Juan‐Carlos , Alvarez‐Larrán Alberto , Gómez Montse , Angona Anna , Amat Paula , Bellosillo Beatriz , Martínez‐Avilés Luz , Navarro Blanca , Teruel Anabel , Martínez‐Ruiz Francisco , Besses Carles
Published: November 2010

Standardized criteria of response to treatment and a unified definition of resistance/intolerance to hydroxycarbamide (HC) in essential thrombocythaemia (ET) have been proposed by the European LeukaemiaNet (ELN). We have retrospectively evaluated such criteria in 166 ET patients treated with HC for a median of 4·5 years. Overall, 134 patients achieved a complete clinicohaematological response (CR) and 25 a partial response. Thirty‐three patients met at least one of the ELN criteria defining resistance (n = 15) or intolerance (n = 21) to HC. Fifteen cases developed anaemia with thrombocytosis, which was associated with a high incidence of myelofibrosis and death from any cause. Other definitions of resistance were less useful. Factors determining the thrombotic risk were a history of prior thrombosis and a baseline leucocyte count >10 × 109/l. Of note, patients achieving a CR, even if sustained during the entire follow‐up, did not benefit from a lower incidence of thrombosis or an improved survival. In conclusion, most ET patients respond to HC, but the achievement of response, as defined by the ELN, does not correlate with the patients’ outcome. The best discriminating ELN criterion of resistance to HC was the detection of anaemia, which also identified a subgroup of patients with poor prognosis.
Intravascular inhibition of factor VIIa and the analogue NN1731 by antithrombin
Authors: Petersen Lars C. , Karpf Ditte M. , Agersø Henrik , Hermit Mette B. , Pelzer Hermann , Persson Egon , Nichols Timothy C. , Ezban Mirella
Published: November 2010

NN1731 is a recombinant activated factor VII (rFVIIa) analogue with increased intrinsic activity. This also applies to its reactivity towards antithrombin (AT), the role of which was investigated in a pharmacokinetic (PK) study. NN1731 or rFVIIa was administered to normal and haemophilia A dogs and elimination was measured by FVIIa clot activity, FVIIa‐ and FVIIa‐AT antigen. In vitro AT complex formation was studied in canine plasma spiked with NN1731 or rFVIIa. Based on FVIIa antigen concentrations, PK profiles in normal and haemophilia A dogs were similar for NN1731 and rFVIIa with antigen half lives, t½ ≈ 1·8 h. In contrast, PK profiles based on activity measurements were distinctly different. NN1731 induced a strong, short lasting (t½ ≈ 0·5 h) pro‐coagulant response, whereas rFVIIa induced a lower, longer lasting (t½ ≈ 1·1 h) response. Western Blot and FVIIa‐AT antigen analysis demonstrated in vivo AT complex formation that accounted for these divergences. AT complex formation with FVIIa or NN1731 in vitro in canine plasma was considerably slower than the in vivo reaction. The results suggest that in vivo inhibition by AT contributes significantly to define drug duration in haemophilia treatment with rFVIIa and in particular with the NN1731 analogue.
X‐linked lymphoproliferative syndrome: a genetic condition typified by the triad of infection, immunodeficiency and lymphoma
Authors: Rezaei Nima , Mahmoudi Elham , Aghamohammadi Asghar , Das Rupali , Nichols Kim E.
Published: November 2010

X‐linked lymphoproliferative disease (XLP) is an inherited immunodeficiency characterized by the clinical triad of increased susceptibility to primary Epstein–Barr virus (EBV) infection, dysgammaglobulinaemia and lymphoma. Most cases are caused by germline mutations in the SH2D1A gene, which encodes the adaptor molecule Signalling Lymphocytic Activation Molecule (SLAM)‐associated protein (SAP). Recently, a subset of patients with an XLP‐like phenotype was found to carry mutations in XIAP, the gene encoding the X‐linked inhibitor of apoptosis protein (XIAP). Studies of XLP patients and Sap−/− mice reveal that loss of SAP expression impairs immune cell activities, such as natural killer and CD8+ T cell cytotoxicity, T cell cytokine production, activation‐induced cell death, germinal centre formation and natural killer T cell development. Efforts to dissect the diverse roles of SAP and XIAP are enhancing our understanding of immune cell biology and defining how genetic defects in these molecules predispose to EBV‐specific as well as more general cellular and humoral immune dysfunction. These studies are also highlighting critical signalling pathways that might be amenable to pharmacological targeting to improve the treatment of XLP and other disorders associated with impaired antiviral and antitumour immunity.
Are family‐centred principles, functional goal setting and transition planning evident in therapy services for children with cerebral palsy?
Authors: Darrah J. , Wiart L. , Magill‐Evans J. , Ray L. , Andersen J.
Published: November 2010

Background  Family‐centred service, functional goal setting and co‐ordination of a child's move between programmes are important concepts of rehabilitation services for children with cerebral palsy identified in the literature. We examined whether these three concepts could be objectively identified in programmes providing services to children with cerebral palsy in Alberta, Canada.

Methods  Programme managers (n= 37) and occupational and physical therapists (n= 54) representing 59 programmes participated in individual 1‐h semi‐structured interviews. Thirty‐nine parents participated in eleven focus groups or two individual interviews. Evidence of family‐centred values in mission statements and advisory boards was evaluated. Therapists were asked to identify three concepts of family‐centred service and to complete the Measures of Process of Care for Service Providers. Therapists also identified therapy goals for children based on clinical case scenarios. The goals were coded using the components of the International Classification of Functioning Disability and Health. Programme managers and therapists discussed the processes in their programmes for goal setting and for preparing children and their families for their transition to other programmes. Parents reflected on their experiences with their child's rehabilitation related to family‐centredness, goal setting and co‐ordination between programmes.

Results  All respondents expressed commitment to the three concepts, but objective indicators of family‐centred processes were lacking in many programmes. In most programmes, the processes to implement the three concepts were informal rather than standardized. Both families and therapists reported limited access to general information regarding community supports.

Conclusion  Lack of formal processes for delivery of family‐centred service, goal‐setting and co‐ordination between children's programmes may result in inequitable opportunities for families to participate in their children's rehabilitation despite attending the same programme. Standardized programme processes and policies may provide a starting point to ensure that all families have equitable opportunities to participate in their child's rehabilitation programme.
Governmental interventions and youth physical activity in France
Authors: Recours R. , Hanula G. , Travert M. , Sabiston C. , Griffet J.
Published: November 2010

Data from a representative sample of 2474 French youth show that, despite a 7‐year French Ministry of Health strategy for nutrition and physical activities, adolescents' motivation to practise sports and physical activities decreased significantly between 2001 and 2008. While this paper focuses on the context of physical activity in France, the general discussion may be applicable to other countries concerned with the obesity pandemic.
Patterns of physical activity in Spanish children: a descriptive pilot study
Authors: Aznar S. , Naylor P. J. , Silva P. , Pérez M. , Angulo T. , Laguna M. , Lara M. T. , López‐Chicharro J.
Published: November 2010

Background  The majority of Spanish adults and children do not engage in enough physical activity to be beneficial for health. There is a need for objective and accurate assessment of the proportion of children meeting the physical activity recommendation for health. Assessing patterns of physical activity both between days (during weekdays and weekend days) and within days is of interest to improve our understanding of the variation in Spanish children's physical activity and to provide efficient intervention programmes.

Methods  A sample of 221 children: 136 9‐year‐old children (68 boys and 68 girls) and 85 15‐year‐old children (36 girls and 49 boys) from 12 urban public schools in Madrid, Spain entered the study. The variables measured were anthropometric characteristics (height, weight, body mass index) and physical activity measured during four consecutive days using the GT1M accelerometer.

Results  Younger children were more active and less sedentary than older ones during week and weekend days. Nine‐year‐old boys and girls achieved significantly (P < 0.05) more moderate to vigorous physical activity (MVPA) and significantly (P < 0.01) less sedentary time than older 15‐year‐old children. During weekdays more children achieved physical activity recommendations versus weekend days. Physical activity patterns analyses indicated that boys achieved relatively high values of MVPA from 1100 till 1300 h (school break) and from 1800 till 2000 h in comparison with the rest of the day. Girls were substantially different, with the 9‐year‐old girls having only two obvious peaks of weekday MVPA at lunch (1300) and after school (1900 h) while the adolescent girls had no clear peak of MVPA.

Conclusions  Few children achieved the level of MVPA recommended for health; at particular risk were adolescent girls. More effort needs to be devoted to promoting appropriate opportunities for Spanish girls across the day and to promoting physical activity during weekends for all children.