Measurement of the cross section and angular correlations for associated production of a Z boson with b hadrons in pp collisions at √s = 7 TeV

A study of proton-proton collisions in which two b hadrons are produced in association with a Z boson is reported. The collisions were recorded at a centre-of-mass energy of 7TeV with the CMS detector at the LHC, for an integrated luminosity of 5:2 fb-1. The b hadrons are identified by means of displaced secondary vertices, without the use of reconstructed jets, permitting the study of b-hadron pair production at small angular separation. Differential cross sections are presented as a function of the angular separation of the b hadrons and the Z boson. In addition, inclusive measurements are presented. For both the inclusive and differential studies, different ranges of Z boson momentum are considered, and each measurement is compared to the predictions from different event generators at leading-order and next-to-leading-order accuracy. Copyright CERN.

Cross-sectional study of 168 patients with hepatorenal tyrosinaemia and implications for clinical practice

Background: Hepatorenal tyrosinaemia (Tyr 1) is a rare inborn error of tyrosine metabolism. Without treatment, patients are at high risk of developing acute liver failure, renal dysfunction and in the long run hepatocellular carcinoma. The aim of our study was to collect cross-sectional data. Methods. Via questionnaires we collected retrospective data of 168 patients with Tyr 1 from 21 centres (Europe, Turkey and Israel) about diagnosis, treatment, monitoring and outcome. In a subsequent consensus workshop, we discussed data and clinical implications. Results: Early treatment by NTBC accompanied by diet is essential to prevent serious complications such as liver failure, hepatocellular carcinoma and renal disease. As patients may remain initially asymptomatic or develop uncharacteristic clinical symptoms in the first months of life newborn mass screening using succinylacetone (SA) as a screening parameter in dried blood is mandatory for early diagnosis. NTBC-treatment has to be combined with natural protein restriction supplemented with essential amino acids. NTBC dosage should be reduced to the minimal dose allowing metabolic control, once daily dosing may be an option in older children and adults in order to increase compliance. Metabolic control is judged by SA (below detection limit) in dried blood or urine, plasma tyrosine (<400 μM) and NTBC-levels in the therapeutic range (20-40 μM). Side effects of NTBC are mild and often transient. Indications for liver transplantation are hepatocellular carcinoma or failure to respond to NTBC. Follow-up procedures should include liver and kidney function tests, tumor markers and imaging, ophthalmological examination, blood count, psychomotor and intelligence testing as well as therapeutic monitoring (SA, tyrosine, NTBC in blood). Conclusion: Based on the data from 21 centres treating 168 patients we were able to characterize current practice and clinical experience in Tyr 1. This information could form the basis for clinical practice recommendations, however further prospective data are required to underpin some of the recommendations.

Cross-correlation frequency resolved optical gating analysis of broadband continuum generation in photonic crystal fiber: Simulations and experiments

Numerical simulations are used to study the temporal and spectral characteristics of broadband supercontinua generated in photonic crystal fiber. In particular, the simulations are used to follow the evolution with propagation distance of the temporal intensity, the spectrum, and the cross-correlation frequency resolved optical gating (XFROG) trace. The simulations allow several important physical processes responsible for supercontinuum generation to be identified and, moreover, illustrate how the XFROG trace provides an intuitive means of interpreting correlated temporal and spectral features of the supercontinuum. Good qualitative agreement with preliminary XFROG measurements is observed. © 2002 Optical Society of America.

Modificación de la diferenciación floral mediante la aplicación de ácido giberélico en naranjos navel

p.401-408

Reconocimiento de los principales clones de Alamo (Populus sp.) cultivados en la provincia de Buenos Aires (Argentina) a través de su morfología floral

p.115-126

Reaching across organisational, sectoral and geographical boundaries: exploring the learning potential of an EU cross-border project

Research This paper outlines some of the key findings from an evaluation of the project and demonstrates that EC funded projects such as this, which seek to promote cross border collaboration and understanding (i.e. across organisational, sectoral and geographical boundaries) offer considerable learning potential – not least about variances in health politics across different communities. However, for this learning to be realised a comprehensive system of knowledge management needs to be an integral part of project planning alongside a system for sustaining embryonic professional networks. The concept of managing relationships was also a key part of the projects success. Executing a project funded by the EU demands the development of complex organisational skills to negotiate all the administrative challenges en route to successful completion and this project in particular relied for its success on the development of social relationships of trust and mutual respect across national, professional and social boundaries. Context A three–year European Commission funded project designed to exchange a wide range of staff (professional semiprofessional and voluntary staff in health and social care) project led by the University of Greenwich (UK) and the Université Catholique de Lille, France was completed this year (February 2008). The project was complex because it involved working in different national contexts, was multi-disciplinary, and demanded the negotiation of multiple boundaries. Theories A mixed method evaluation including written reports gathered immediately after each exchange visit and a post hoc series of individual interviews and focus groups was conducted in order to gain qualitative information (from the participants perspective) on their experiences and to identify any learning gained. Results Analysis of the data provided evidence of learning on a number of levels; personally, inter and intra professionally and organisationally as well as across sectors and also from a project management perspective. The learning crystallised around the extent of the differences noted by the participants between the UK and the French health and social care systems despite geographical proximity, common membership of the EU and many shared challenges in health and social care. The extent of these differences, noted at every level from policy to practice proved a rich source for reflection on organisational philosophies, ways of working, distribution of resources, professional roles and autonomy and professional registration and mobility - in short on health politics at ‘macro’ and ‘micro’ levels.

Cross-cultural partnerships must talk to build trust

Academic partnerships bring knowledge and drive economic growth, but success depends on good communications that build trust, says Tim Gore.

Solid phase velocity measurements utilising electrostatic sensors and cross correlation signal processing

Gas-solids two phase systems are widely employed within process plant in the form of pneumatic conveyors, dust extraction systems and solid fuel injection systems. The measurement of solids phase velocity therefore has wide potential application in flow monitoring and, in conjunction with density measurement instrumentation, solids mass flow rate measurement. Historically, a number of authors have detailed possible measurement techniques, and some have published limited test results. It is, however, apparent that none of these technologies have found wide application in industry. Solids phase velocity measurements were undertaken using real time cross correlation of signals from two electrostatic sensors spaced axially along a pipeline conveying pulverised coal (PF). Details of the measurement equipment, the pilot scale test rig and the test results are presented.

Seasonal plankton dynamics along a cross-shelf gradient off northern Spain

The development of population models able to reproduce the dynamics of zooplankton is a central issue when trying to understand how a changing environment would affect zooplankton in the future. Using 10 years of monthly data on phytoplankton and zooplankton abundance in the Bay of Biscay from the IEO's RADIALES time-series programme, we built non-parametric Generalized Additive Models (GAMs) able to reproduce the dynamics of plankton on the basis of environmental factors (nutrients, temperature, upwelling and photoperiod). We found that the interaction between these two plankton components is approximately linear, whereas the effects of environmental factors are non-linear. With the inclusion of the environmental variability, the main seasonal and inter-annual dynamic patterns observed within the studied plankton assemblage indicate the prevalence of bottom-up regulatory control. The statistically deduced models were used to simulate the dynamics of the phytoplankton and zooplankton. A good agreement between observations and simulations was obtained, especially for zooplankton. We are presently developing spatio-temporal GAM models for the North Sea based on the Continuous Plankton Recorder database.