bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulations of full impact of the Large Hadron Collider beam with a solid graphite target
Authors: Tahir N.A. , Schmidt R. , Brugger M. , Shutov A. , Lomonosov I.V. , Piriz A.R. , Hoffmann D.H.H. 
Published: July 2009

AbstractThe Large Hadron Collider (LHC) will operate with 7 TeV/c protons with a luminosity of 1034 cm−2 s−1. This requires two beams, each with 2808 bunches. The nominal intensity per bunch is 1.15 × 1011protons and the total energy stored in each beam is 362 MJ. In previous papers, the mechanisms causing equipment damage in case of a failure of the machine protection system was discussed, assuming that the entire beam is deflected onto a copper target. Another failure scenario is the deflection of beam, or part of it, into carbon material. Carbon collimators and beam absorbers are installed in many locations around the LHC close to the beam, since carbon is the material that is most suitable to absorb the beam energy without being damaged. In case of a failure, it is very likely that such absorbers are hit first, for example, when the beam is accidentally deflected. Some type of failures needs to be anticipated, such as accidental firing of injection and extraction kicker magnets leading to a wrong deflection of a few bunches. Protection of LHC equipment relies on the capture of wrongly deflected bunches with beam absorbers that are positioned close to the beam. For maximum robustness, the absorbers jaws are made out of carbon materials. It has been demonstrated experimentally and theoretically that carbon survives the impact of a few bunches expected for such failures. However, beam absorbers are not designed for major failures in the protection system, such as the beam dump kicker deflecting the entire beam by a wrong angle. Since beam absorbers are closest to the beam, it is likely that they are hit first in any case of accidental beam loss. In the present paper we present numerical simulations using carbon as target material in order to estimate the damage caused to carbon absorbers in case of major beam impact.
Infinitely generated free nilpotent groups: completeness of the automorphism groups
Authors: TOLSTYKH VLADIMIR 
Published: July 2009

AbstractWe transfer the results of Dyer, Formanek and Kassabov on the automorphism towers of finitely generated free nilpotent groups to infinitely generated free nilpotent groups. We prove that the automorphism groups of infinitely generated free nilpotent groups are complete. By combining the results of Dyer, Formanek and Kassabov with the results in this paper, one gets that the automorphism tower of any free nilpotent group terminates after finitely many steps.
De la biologie à l'éthique les comités d'éthique de biologie
Authors: Bernard Jean 
Published: July 2009

Bioethics has been stimulated by two happenings. Indignation provoked by the behaviour of Hitler's regime against the unfortunate deportees and the splendid progress of biology and medicine. One can distinguish two periods in the history of ethical committees. Firstly a period concerned only with local regional, hospital or university committees and a later period concerned with national committees (the first was created in France in 1983).Three revolutions which pose important ethical questions have changed medicine in the last fifty years:1. A therapeutic revolution with therapeutic trials (well organised trials on healthy volunteers, or comparative trials which are both morally necessary and necessarily immoral).2. Organ transplantation with questions about the donor (dead or living) or the recipient who becomes a chimera.3. Epidemiological enquiries with the difficult question of creating a register.The biological revolution which came later has given man three masteries:1. Developments in birth control, such as the RU of Baulieu, which can terminate pregnancy.2. Artificial insemination ranging from treating male infertility to a matter of convenience.3. In vitro fertilisation leads to the problem of what to do with supernumerary embryos.Genetic developments lead to progress in predicting the predisposition to disease as well as the power to modify the inherited genetic makeup. The invention but not the discovery can be patented. Finally progress in knowledge of the nervous system leads to two important bioethical problems, psychopharmacology and nerve tissue grafts.These difficult questions and the tensions that they have engendered have led ethical committees to formulate the following principles to guide their judgement:1. The definition of a person at the very beginning of life, with the tendency to consider an embryo as a potential person.2. Respect for knowledge depends on two precautions; confining some research to a small number of laboratories and having a moratorium on some new findings.3. Eliminating the financial element from blood transfusions or organ donation.4. The responsibility of the researcher who should deal with the ethical problems created by his or her research as it develops.What is the role of the law in ethics? What legislation can be and what cannot be forecast? How can we develop the teaching of bioethics particularly in higher education, medicine and law? Can we start sufficiently early teaching morality in schools? How do we develop the necessary international arrangements? By increasing meetings? By creating a European bioethics committee? Finding an answer to these questions was the object of a meeting in Madrid in March 1992 of the chairmen of the national ethical committees of Europe.
Nation, nationalism and citizenship
Authors: Touraine Alain 
Published: July 2009

The idea of nation has been created in Holland and Britain, in the United States and France, as a community of citizens, as a political society which gives a practical expression to universal rights by transforming freedom, equality and justice, into laws and reforms.But, even if the claim for national independence has often associated universalistic principles with the defense of a concrete, historically and culturally defined community, from the second half of the XIXth Century on, aggressive nationalism has been more and more predominant as the defense of the specificity and even of the superiority of a givenVolkorNarod, to mention German and Russian notions. We reached extreme points of anti-liberalism, both with a racial or ethnic definition of the nation and with a cultural or a religious one.It is inaccurate to think that economic globalization overcomes and limits nationalism. On the contrary, our world is dominated by the growing separation between ‘open’ economies and ‘closed’ cultures, dissociation which entails a basic crisis or even a decomposition of all social and political mediations.We feel the necessity to reassert the role of political, national or local institutions not as instruments of legitimation of the State but as mediations between globalized economies and identity-obsessed cultures.
1090 MHz channel capacity improvement in the air traffic control context
Authors: Piracci Emilio G. , Galati Gaspare , Petrochilos Nicolas , Fiori Fabrizio 
Published: July 2009

The aim of this study is to increase the capacity of the 1090 MHz secondary surveillance radar (SSR) channel by novel transmission and decoding techniques. In particular, multilateration stations have omni-directional antennae; hence considering aircraft traffic and including the extension of surveillance to cooperating vehicles, the reception of superimposed signals is more and more probable. We propose mitigating this problem by combining frequency agility and source separation techniques; we analyze the pertaining channel capacity improvement, and then evaluate the detection and timing estimation for frequency-shifted and separated signals.
Airborne passive location based on combined time and frequency difference of arrival
Authors: Severino Gaetano , Zaccaron Antonio , Ardoino Riccardo 
Published: July 2009

Passive location techniques have always been considered an important topic and recently, thanks to digital signal processing (DSP) advances, new methods are being studied and experimented with. The possibility to passively locate radar emitters avoiding transmission is crucial in a variety of military applications, in particular when a flying platform (aircraft or helicopter) is entering an unknown and potentially hostile area. Elettronica SpA (ELT) gave start in 2004 to an experimental campaign in this field with the support and collaboration of the Italian Ministry of Defence (MoD). In this context the following activities were carried out:
–theoretical study (with analytically derived and simulated results) of a passive location algorithm,–design and development of a passive location demonstrator (PLD) qualified for flight,–field tests (July 2006) performed in Sardegna (Salto di Quirra).This paper presents the specific passive location algorithm selected for the field tests illustrating analytical performance prediction. The PLD and the field tests are described and the main results are reported. A location accuracy in the order of 10% of emitter distance has been achieved during experimentation.
Reactivity to alcohol assessment measures: an experimental test
Authors: Walters Scott T. , Vader Amanda M. , Harris T. Robert , Jouriles Ernest N. 
Published: July 2009

ABSTRACTAims  Previous research has suggested that alcohol screening and assessment may affect drinking.Design  This study was a randomized test of reactivity to alcohol assessment questionnaires among a group of heavy drinking college students.Setting and participants  A total of 147 university students completed a screening questionnaire and were randomized to either immediate assessment or delayed assessment. The immediate assessment group completed a set of drinking questionnaires at baseline, 3, 6 and 12 months, while the delayed assessment group completed questionnaires only at 12 months.Measurements  Primary outcomes included overall volume of drinking, risky drinking and use of risk reduction behaviors.Findings  We found a significant effect of assessment on measures of risky drinking and risk reduction behaviors, but not on overall volume of drinking. Specifically, at 12 months, participants who had previously completed drinking assessments had a lower peak blood alcohol concentration (BAC) (d = −0.373), were more likely to report a low score on the Alcohol Use Disorders Identification Test (AUDIT; odds ratio = 2.55) and tended to use more strategies to moderate their alcohol consumption (d = 0.352). Risk reduction behaviors that were affected tended to be those that limited alcohol consumption, rather than those that minimized consequences.Conclusions  These results may have implications for the development of brief interventions.
The impact of changing nicotine replacement therapy licensing laws in the United Kingdom: findings from the International Tobacco Control Four Country Survey
Authors: Shahab Lion , Cummings K. Michael , Hammond David , Borland Ron , West Robert , McNeill Ann 
Published: July 2009

ABSTRACTAim  To evaluate the impact of a new licence for some nicotine replacement therapy products (NRT) for cutting down to stop (CDTS) on changes in the pattern of NRT use.Design  Quasi‐experimental design comparing changes in NRT use across two waves of a population‐based, replenished‐panel, telephone survey conducted before and after the introduction of new licensing laws in the United Kingdom with changes in NRT use in three comparison countries (Australia, Canada and United States) without a licensing change.Participants  A total of 7386 and 7013 smokers and recent ex‐smokers participating in the 2004 and/or 2006/7 survey.Measurements  Data were collected on demographic and smoking characteristics as well as NRT use and access. In order to account for interdependence resulting from some participants being present in both waves, generalized estimation equations with an exchangeable correlation matrix were used to assess within‐country changes and linear and logistic regressions to assess between‐country differences in adjusted analyses.Findings  NRT use was more prevalent in the United Kingdom and increased across waves in all countries but no wave × country interaction was observed. There was no evidence that the licensing change increased the prevalence of CDTS or the use of NRT (irrespective of how it was accessed) for CDTS in the United Kingdom relative to comparison countries. There was also no evidence for a change in concurrent smoking and NRT use among smokers not attempting to stop in the United Kingdom relative to comparison countries.Conclusion  The addition of the CDTS licence for some NRT products in the United Kingdom appears to have had very limited, if any, impact on NRT use in the first year after the licence change.
Early weaning and alcohol disorders in offspring: biological effect, mediating factors or residual confounding?
Authors: Alati Rosa , Van Dooren Kate , Najman Jake M. , Williams Gail M. , Clavarino Alexandra 
Published: July 2009

ABSTRACT Aims This study explores associations between early weaning and alcohol use disorders in youth and mechanisms by which these associations may operate. Design We used data from the Mater University Study of Pregnancy and its outcomes, an Australian birth cohort study based in Brisbane. Setting and participants: This study is based on a subsample of 2370 participants for whom complete data were available at age 21 years. Length and method of breastfeeding were assessed at 6 months. Measurements Alcohol use disorders were assessed at age 21 using the life‐time version of the Composite International Diagnostic Interview—computerized version (CIDI‐Auto). We adjusted for maternal age, marital status, education, alcohol, tobacco use, anxiety, depression and maternal attitudes towards the baby. Attention Deficit and Hyperactivity Disorders (ADHD) and Intellect Quotient (IQ) were measured with the Child Behaviour Checklist (5 years) and the Ravens SM (14 years), respectively. Findings Those who had been weaned within 2 weeks of being born and breastfed at regular intervals were at increased risk of meeting criteria for alcohol use disorders at age 21 [odds ratio (OR) 1.71, 95% confidence interval (CI):1.07, 2.72]. Conclusion This study confirms a small but robust association between early weaning and increased risk of alcohol use disorders.
Ascites improves upon plus serum sodium model for end‐stage liver disease (MELD) for predicting mortality in patients with advanced liver disease
Authors: SOMSOUK M. , GUY J. , BIGGINS S. W. , VITTINGHOFF E. , KOHN M. A. , INADOMI J. M. 
Published: July 2009

SummaryBackground  The clinical impact of ascites has historically been well recognized; however, its value is unclear in the context of current prognostic models.Aim  To determine whether ascites can improve risk discrimination beyond model for end‐stage liver disease (MELD) and serum sodium (MELDNa).Methods  Consecutive cirrhotic patients were evaluated for ascites on the basis of an outpatient CT along with concurrent MELD and Na values. Cox models were used to determine the added value of ascites for predicting 1‐year mortality. Increases in the C‐index, integrated discrimination improvement (IDI) and the net reclassification index (NRI) were used to assess improvements in discrimination after the addition of ascites.Results  A total of 1003 patients had Na and MELD scores available within 30 days of the CT scan. A total of 60 deaths occurred within 1 year, with mortality higher in patients with ascites (21.4% vs. 4.0%, HR 6.08, 95% CI 3.62–10.19, P < 0.0005). In the presence of ascites, the MELD and MELDNa scores underestimated mortality risk when the scores were less than 21. The addition of ascites to the MELDNa model substantially improved discrimination by the C‐index (0.804 vs. 0.770, increase of 3.4%, 95% CI 0.2–9.9%), IDI (1.8%, P = 0.016) and NRI (15.8%, P = 0.0006).Conclusion  The incorporation of radiographic ascites significantly improves upon MELDNa for predicting 1‐year mortality. The presence of ascites may help identify patients at increased risk for mortality, not otherwise captured by either MELD or MELDNa.
3D seismic imaging of a Tertiary Dyke Swarm in the Southern North Sea, UK
Authors: Wall Mostyn , Cartwright Joe , Davies Richard , McGrandle Andrew 
Published: July 2009

ABSTRACTWe use three‐dimensional (3D) seismic reflection and magnetic data to interpret and describe the 3D geometry of igneous dykes in the southern North Sea. The dykes were emplaced into Paleozoic and Mesozoic sediments and have a common upper termination in Early Tertiary sediments. We interpret the dykes to be part of the British Tertiary volcanic province and estimate the age of the dykes to be 58 Ma. The dykes are characterized by a narrow 0.5–2 km wide vertical disturbance of seismic reflections that have linear plan view geometry. Negative magnetic anomalies directly align with the vertical seismic disturbance zones and indicate the presence of igneous material. Linear coalesced collapse craters are found above the dykes. The collapse craters have been defined and visualized in 3D. Collapse craters have formed above the dyke due to the release of volatiles at the dyke tip and resulting volume loss. Larger craters have potentially formed due to explosive phreatomagmatic interaction between magma and pore water. The collapse craters are a new Earth analogue to Martian pit chain craters.
Wind velocity perturbation of soil respiration measurements using closed dynamic chambers
Authors: Suleau M. , Debacq A. , Dehaes V. , Aubinet M. 
Published: July 2009

SummarySoil respiration measurements performed with closed dynamic chambers are very sensitive to pressure differences inside and outside the chamber: differences as small as 1 Pa can induce errors that are of the same magnitude as the flux itself. The problem is usually solved by adding a vent to the experimental set‐up. However, although this may give acceptable results in most cases, it is not effective at sites that are very exposed to wind. At the CarboEurope–IP agricultural site of Lonzée (Belgium), on bare soil, we used a vent composed of a vertical tube whose upper end was placed between two horizontal plates. Whilst this system worked properly in low‐wind conditions, it led to a significant flux over‐estimation (up to 300%) under strong wind conditions. We analysed the causes of this error and attributed it to a dynamic pressure effect at the vent, leading to air aspiration from within the chamber. We suggest that this is because the wind at the vent level was not the same as that experienced in the chamber, because of the large vertical wind speed gradient close to the soil. Another vent geometry was then proposed that positioned the vent at the chamber level. This new design was tested on both manual and automatically operated chambers. It was found to be efficient in windy conditions as most of the artificial correlation between soil respiration measurements and wind speed had disappeared.
Rate of spread of fires in Calluna vulgaris‐dominated moorlands
Authors: Davies Gwilym M. , Legg Colin J. , Smith Alexander A. , MacDonald Angus J. 
Published: July 2009

Summary 1.
Calluna‐dominated heaths occur throughout Europe but are in decline across their range. There is growing interest in using prescribed burning for their management, but environmental and social change will impact future fire regimes. Understanding fire behaviour is vital for the sustainable use of fire, but no robust models exist to inform management. 2.  Shrub fuels display complex fire behaviour. This is particularly true in UK moorlands which are unusual in their fuel structure and moisture regime, being dominated by live fuel and an oceanic climate. 3.  We burnt 27 experimental fires in the Scottish uplands during the legal burning season using a replicated experimental design. Plots were assigned to one of three commonly identified growth phases. We estimated a range of prefire fuel characteristics, including heterogeneity in fuel structure. We recorded wind speed and direction and estimated rate of spread (RoS). 4.  Redundancy analysis was used to investigate the relationship between fire behaviour parameters as a whole and control variables. Fuel structure and heterogeneity, wind speed and canopy fuel moisture content were strongly related to variation in fire behaviour. 5.  Best subsets regression was used to generate models of fire spread based on wind speed, vegetation height, canopy fuel moisture and an index of fuel heterogeneity. RoS was determined largely by wind speed, but this interacted strongly with vegetation structure. Changes in fuel horizontal continuity and vertical structure reduced rates of spread in low wind speeds. 6.
Synthesis and applications. Live fuel moisture and fuel heterogeneity play an important role in dampening fire behaviour, aspects of shrub fuels that have previously not been examined in detail. Careful use of fire for moorland management increases habitat diversity and creates fire‐safe landscapes. Escaped prescribed fires burn large areas, homogenize landscapes and have severe impacts on ecosystem services. The complex relationship between fuel structure and wind speed implies that changes in behaviour can be rapid and unexpected. Models can be used to assess fire hazard prior to prescribed burning and to choose fuels that can be burnt safely under prevailing or forecast conditions.
Fishing impacts on the marine inorganic carbon cycle
Authors: Jennings Simon , Wilson Rod W. 
Published: July 2009

Summary1. Teleost fish excrete precipitated carbonate and make significant contributions to the marine inorganic carbon cycle at regional and global scales. As total carbonate production is linked to fish size and abundance, fishing is predicted to affect carbonate production by modifying fish abundance and size‐structure.2. We draw on concepts from physiology, metabolic ecology, life history theory, population dynamics and community ecology to develop, validate and apply analytical tools to assess fishing impacts on carbonate production. Outputs suggest that population and community carbonate production fall rapidly at lower rates of fishing than those used as management targets for sustainable yield.3. Theoretical predictions are corroborated by estimated trends in carbonate production by a herring population and a coral reef fish community subject to fishing. Our analytical results build on widely applicable relationships between life history parameters and metabolic rates, and can be generalized to most fished ecosystems.4. Synthesis and applications. If the maintenance of chemical processes as well as biological process were adopted as a management objective for fisheries then the methods we have developed can be applied to assess the effects of fishing on carbonate production and to advise on acceptable rates of fishing. Maintenance of this ecosystem service would require lower rates of fishing mortality than those recommended to achieve sustainable yield.