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The HL-LHC IT STRING, an integrated test stand for the major components of the HL-LHC Inner Triplet (IT) zone, is in its construction phase in a surface building at CERN. The main motivation is to study and validate the collective behavior of the different systems: magnets, circuit protection, cryogenics for magnets and superconducting link, magnet powering, vacuum, alignment, and interconnections between magnets and superconducting link. During the past two years, the major focus has been on the technical infrastructure definition and implementation, while preparing the installation sequences and procedures for the major elements. The String Validation Program (SVP) has been agreed with the HL-LHC Work Packages, allowing to set up a joint and optimized test program and to integrate it in a schedule. In this paper we describe the IT String installations and describe the main differences between the HL-LHC IT String and the future HL-LHC machine. The main line of the test program and the motivation of a full thermal cycle with a cost benefit analysis will be presented.

Um die Frequenz rezidivierender Harnwegsinfektionen (rHWI) und die damit verbundene fortwährende Zunahme multiresistenter Uropathogene zu reduzieren, werden neuartige Präventionsmaßnahmen und Therapieansätze benötigt. Ziel dieser Übersichtsarbeit ist es, die aktuell verfügbare Evidenz über das Mikrobiom der Harnblase gesunder Frauen und solcher mit rHWI systematisch zu präsentieren. Außerdem werden relevante Studien zur Wirksamkeit von Probiotika bei rHWI strukturiert dargestellt. Hierdurch soll der gegenwärtige Stand der Forschung und ein Ausblick auf eine Therapie abseits der üblichen antimikrobiellen Behandlungsoptionen gegeben werden.

Copper-based catalysts gain activity through the presence of poorly coordinated Cu atoms and incomplete oxidation at the surface. The catalytic mechanisms can in principle be observed by controlled dosing of reactants to single-crystal substrates. However, the interconnected influences of surface defects, partial oxidation, and adsorbate coverage present a large matrix of conditions that have not been fully explored in the literature. We recently characterized oxygen and carbon monoxide coadsorption on Cu(111), a nominally defect-free surface, and now extend our study to the stepped surface Cu(211). Temperature-programmed desorption of CO adsorbed to bare metal surfaces confirms that two sites dominate desorption from a saturated layer: atop terrace atoms of local (111) character and atop step edge atoms with CO bound more strongly to the latter. At low coverage, discrete CO resonances in reflection adsorption infrared spectra can be assigned to these sites: 2077 cm–1for extended (111) terraces, 2093 cm–1for step sites, and additional kink-adsorbed molecules at 2110 cm–1. With increasing coverage, in contrast to Cu(111), the infrared spectral features on Cu(211) evolve and shift as a consequence of dipole–dipole coupling between differentially occupied types of sites. Auger electron spectroscopy shows that exposure to background O2oxidizes the (211) surface at a rate nearly 1 order of magnitude greater than (111); we argue that the resulting surface is stoichiometric Cu2O, as previously found for Cu(111). This oxide binds CO less strongly than the bare metal and the underlying crystal cut continues to influence the adsorption sites available to CO. On oxidized (111) terraces, broad absorption peaks at 2115–2120 cm–1; on oxidized Cu(211), CO adsorbed to step sites appears as a resolved secondary peak at 2144 cm–1. This suite of spectroscopic signatures, obtained under carefully controlled conditions, will help to determine the origin and fate of adsorbed species in future studies of reaction mechanisms on copper.

The olive tree was an iconic plant for most of the past Mediterranean civilizations, for which it had important economic value. Here we report the earliest use of fruits and wood from olive trees in Africa so far, around 100,000 years ago. These findings suggest the presence of olive trees on the Atlantic coast of Morocco during most of the last glacial period, and the use of olives by the early Homo sapiensfor fuel management and most probably for consumption.

The main goal of this work is to test the possibility of a newly introduced constitutive law to model the behaviour of the isotropic elastic-perfectly plastic material which is exposed to large elastoplastic deformations. The proposed constitutive relation is based on the hypo-elastic relation and the inelastic INTERATOM model. The verification of the model is done by its implementation into the commercial software ABAQUS/Standard via the user subroutine UMAT. For that purpose, the large simple shear problem is studied where selected objective corotational rates, i.e. the logarithmic rate, the Jaumann rate and the Green-Naghdi rate, are individually implemented in the aforementioned constitutive relations. The obtained results are compared mutually and with the relevant literature. The proposed constitutive model is also used to test the behaviour of the part of a real engineering structure, i.e. a seismic isolator, in order to obtain the correct input data for further analysis of superstructure behaviour due to seismic excitation.

To determine the effects of Rheumates@Work, an internet‐based program supplemented with 4 group sessions, aimed at improving physical activity, exercise capacity, health‐related quality of life (HRQoL), and participation in children with juvenile idiopathic arthritis. Patients were recruited from 3 pediatric rheumatology centers in The Netherlands for an observer‐blinded, randomized controlled multicenter trial. Physical activity level, time spent in rest, light, and moderate‐to‐vigorous physical activity (MVPA) were recorded in a diary and with an accelerometer, before intervention, after intervention, and at followup after 3 and 12 months (intervention group only). Exercise capacity was assessed using the Bruce treadmill protocol, HRQoL was assessed with the Pediatric Quality of Life Inventory generic core scale, and participation in school and in physical education classes were assessed by questionnaire. The intervention group consisted of 28 children, and there were 21 children in the control group. MVPA,exercise capacity, and participating in school and physical education classes improved significantly in the intervention group. HRQoL improved in the control group. No significant differences were found between groups. The effect of Rheumates@Work on physical activity and exercise capacity lasted during the 12 months of followup. Improvements in physical activity were significantly better for the cohort starting in winter compared to the summer cohort. Rheumates@Work had a positive, albeit small, effect on physical activity, exercise capacity, and participation in school and physical education class in the intervention group. Improvements lasted for 12 months. Participants who started in winter showed the most improvement. Rheumates@Work had no effect on HRQoL.

In the framework of crystal plasticity, a new cyclic polycrystalline viscoplastic model is constructed to describe the uniaxial ratchetting of a body centered cubic (BCC) metal. At the intra-granular scale, a combined kinematic hardening rule similar to the Ohno-Abdel-Karim model is employed to address the ratchetting within each single crystal grain; and two sets of slip systems with different resistances to dislocation slip, i.e., primary and secondary ones, are considered to capture the physical nature of dislocation slips in a body centered cubic (BCC) metal. At the inter-granular scale, an explicit transition rule is adopted to extend the single crystal approach into a polycrystalline version. It is shown that the proposed model describes the uniaxial ratchetting of annealed 42CrMo steel, a body centered cubic (BCC) metal, reasonably. Also, it is seen that the crystal orientation influences significantly the ratchetting of body-centered cubic (BCC) single crystals.

An efficient numerical framework suitable for three-dimensional analyses of brittle material failure is presented. The proposed model is based on an (embedded) Strong Discontinuity Approach (SDA). Hence, the deformation mapping is elementwise additively decomposed into a conforming, continuous part and an enhanced part associated with the kinematics induced by material failure. To overcome locking effects and to provide a continuous crack path approximation, the approach is extended and combined with advantages known from classical interface elements. More precisely, several discontinuities each of them being parallel to a facet of the respective finite element are considered. By doing so, crack path continuity is automatically fulfilled and no tracking algorithm is necessary. However, though this idea is similar to that of interface elements, the novel SDA is strictly local (finite element level) and thus, it does not require any modification of the global data structure, e.g., no duplication of nodes. An additional positive feature of the advocated finite element formulation is that it leads to a symmetric tangent matrix. It is shown that several simultaneously active discontinuities in each finite element are required to capture highly localized material failure. The performance and predictive ability of the model are demonstrated by means of two benchmark examples.

The transition state theory allows parameters, such as the pre‐exponential factor and the activation energy, to be associated with the active centers. These parameters are indicators of the way in which a technical process can be described even if the dominant geometries acting between the species adsorbed and the substrate are not known precisely. The process of modeling methanol synthesis shown here indicates that elementary reactions can be combined with simple coupled differential equations to allow important conclusions to be drawn about the surface reactions of the catalyst.

We have investigated coadsorption of H2O and Oadon the stepped Pt(533) surface using temperature-programmed desorption in combination with isotope exchange. Water desorption from both bare and oxygen precovered Pt(533) gives rise to three easily identifiable peaks in the TPD spectrum between 140−210 K. Only in coadsorption experiments does a desorption feature at ∼270 K appear, which we ascribe to recombinative desorption of OHadon step sites. If the surface is saturated with Oad, we also observe a broadening of the desorption peak at 188 K, indicative of OH formation on terrace sites. Oddly, the magnitude of the isotope exchange hardly varies with Oadprecoverage. Detailed analysis of the results suggest a strong bias for OHterraceformation over OHstepformation. This is likely related to the extent to which OHadcan be incorporated into a larger hydrogen bonded network. In spite of the observation that OHstepis more strongly bound than OHterrace, the overall exchange on the Pt(533) surface is much lower than on Pt(111).

ObjectivePatients with juvenile idiopathic arthritis JIA are less physically active than healthy peers. Therefore, we developed an Internetbased intervention to improve physical activity PA. The aim of this study was to examine the effectiveness of the program in improving PA.MethodsPA was determined by activityrelated energy expenditure, PA level, time spent on moderate to vigorous PA, and the number of days with ≥1 hour of moderate to vigorous activity, and was assessed with a 7day activity diary. Aerobic exercise capacity was assessed by means of a Bruce treadmill test and was recorded as maximum endurance time. Disease activity was assessed by using the JIA core set. Adherence was electronically monitored.ResultsOf 59 patients, 33 eligible patients were included and randomized in an intervention n 17, mean ± SD age 10.6 ± 1.5 years or control waitinglist group n 16, mean ± SD age 10.8 ± 1.4 years. All patients completed baseline and T1 testing. PA significantly improved in both groups. Maximum endurance time significantly improved in the intervention group but not in the control group. In a subgroup analysis for patients with low PA intervention: n 7, control: n 5, PA improved in the intervention group but not in the control group. The intervention was safe, feasible, and showed a good adherence.ConclusionAn Internetbased program for children with JIA ages 8–12 years directed at promoting PA in daily life effectively improves PA in those patients with low PA levels. It is also able to improve endurance and it is safe, feasible, and has good adherence.

Auf Basis von elementaren Reaktionen wird ein mathematisches Modell erstellt, das den Einblick in das chemische Geschehen der heterogen katalysierten Epoxidierung von 1,3Butadien am AgKatalysator im LaborRohrreaktor ermöglicht. Dazu wird der Reaktionsmechanismus auf ein System von 29 gekoppelten Differentialgleichungen transformiert. Insgesamt ergibt sich ein Reaktionssystem aus 56 Reaktionen, die alle über eine komplexe Verbindung mit dem aktiven Zentrum Z des Katalysators verfügen. Jede Reaktion des Systems besteht aus zwei ArrheniusParametern präexponentieller Faktor und Aktivierungsenergie, sodass sich insgesamt 112 Parameter ergeben. Der erforderliche Datensatz wird aus Experimenten extrahiert, die im LaborRohrreaktor durchgeführt werden. Für die Epoxidierung wird ein AgKatalysator eingesetzt, der durch simultane Nassimprägnierung Incipient wetness method eines Al2O3Trägers mit wässriger Aktivkomponentenlösung AgNO3, CsNO3, BaNO32 hergestellt wird. Die Versuche finden anhand ausgewählter Temperaturpunkte unter isothermen Bedingungen für die Raumgeschwindigkeiten 2950 und 5900 h–1bei Umgebungsdruck statt. Für die signifikantesten Produkte 3,4Epoxy1buten, CO2und CO stimmen die modellierten mit den experimentellen Werten gut überein. Aus dem Modell ergibt sich für die Entstehung des molekularen Zielproduktes 3,4Epoxy1buten aus dem komplexen Oberflächenzentrum Z eine Aktivierungsenergie von 26,02 kJmol.

Diese Arbeit untersucht die Machbarkeit der Agkatalysierten Epoxidierung von 1,3Butadien 1,3BD zu 3,4Epoxy1buten EpB in einem am Forschungszentrum Karlsruhe entwickelten Mikroreaktor MR 1. Für Vorversuche kommt ein Rohrreaktor RR zum Einsatz. Als Katalysator wird ein Al2O3Träger eingesetzt, auf dem die Aktivkomponenten aufgebracht sind. Die Epoxidierung erfolgt im Bereich von 180 °C bis 320 °C und Raumgeschwindigkeiten RG von 2950 h–1bis 17 701 h–1bei Umgebungsdruck in einem Katalysatorteststand. Die höchste EpBSelektivität von 52  wird bei einem 1,3BDUmsatz von 2,1  und einer RG von 8851 h–1mit mikrostrukturierten TiFolien bei 240 °C erreicht.

In a study preliminary to investigating CO2dissociation, we report our results on oxygen and carbon monoxide coadsorption on Cu(111). We use reflection adsorption infrared spectroscopy and Auger electron spectroscopy to characterize and quantify adsorbed species. On clean Cu(111), the CO internal stretch mode appears initially at 2077 cm–1for a surface temperature of ∼80 K. We accurately reproduce the previously determined redshift of the absorption band with increasing CO coverage. We subsequently oxidize the surface by exposure to O2at 300 K to ensure O2dissociation. The band’s frequency and line shape of subsequently adsorbed CO at ∼80 K are not affected. However, the maximum absorbance and integrated peak intensities drop with increasing O coverage. The data suggest that CO is not adsorbed near O, likely as a consequence of the mechanism of Cu(111) surface oxidation by O2at 300 K. We discuss whether our RAIRS results may be used to quantify CO2dissociation in the zero-coverage limit.

ObjectiveTo explore physical activity PA in adolescents with juvenile idiopathic arthritis JIA compared with a healthy population and to examine associations between PA and diseaserelated factors.MethodsTotal energy expenditure TEE, activityrelated energy expenditure AEE, PA level, and PA pattern were assessed with a 3day activity diary. Aerobic capacity was assessed using a Symptom Limited Bicycle Ergometry test. Functional ability was assessed with the Childhood Health Assessment Questionnaire. Disease activity was assessed using Paediatric Rheumatology International Trials Organisation core set criteria. Overall wellbeing was measured using a visual analog scale, and time since diagnosis was assessed by retrospective study from patients charts. We used a crosssectional study design. Reference data were collected from healthy Dutch secondary school children.ResultsThirty patients and 106 controls were included mean ± SD age 17.0 ± 0.6 and 16.7 ± 0.9 years, respectively. TEE, AEE, and PA level were significantly lower in the JIA group. The JIA group spent more time in bed and less time on moderate to vigorous PA. Only 23 of the JIA patients met public health recommendations to perform ≥1 hour daily moderate to vigorous PA compared with 66 in the reference group. Higher PA was associated with higher levels of wellbeing and maximal oxygen consumption.ConclusionAdolescents with JIA have low PA levels and are at risk of losing the benefits of PA. Low PA is not related to disease activity, and control over the disease does not restore previous PA levels. Interventions by pediatric rheumatologists are needed to increase PA levels in patients with JIA.

To examine the aerobic and anaerobic exercise capacity in adolescents with juvenile idiopathic arthritis (JIA) compared with age‐ and sex‐matched healthy individuals, and to assess associations between disease‐related variables and aerobic and anaerobic exercise capacity.Of 25 patients enrolled in a JIA transition outpatient clinic, 22 patients with JIA were included in this study (mean ± SD age 17.1 ± 0.7 years, range 16–18 years). Aerobic capacity was examined using a Symptom Limited Bicycle Ergometry test. Anaerobic capacity was assessed with the Wingate Anaerobic Test. Functional ability was assessed with the Childhood Health Assessment Questionnaire. Pain and overall well‐being were measured using a visual analog scale. Disease duration and disease activity were also assessed.Absolute and relative maximal oxygen consumption in the JIA group were significantly impaired (85% and 83% for boys, respectively; 81% and 78% for girls, respectively) compared with healthy controls. Mean power was also significantly impaired (88% for boys and 74% for girls), whereas peak power was significantly impaired for girls and just failed significance for boys (67% for girls and 92% for boys). A post hoc analysis correcting for underweight and overweight demonstrated that body composition did not influence the results substantially.This study demonstrated that adolescents with JIA have an impaired aerobic and anaerobic exercise capacity compared with healthy age‐ and sex‐matched peers. The likely cause for this significant impairment is multifactorial and needs to be revealed to improve treatment strategies.

Recently it has been demonstrated that the classical Prandtl/Reuss theory based on the additive split of the deformation rate contrary to what is believed so far is possible to establish a consistent Eulerian rate formulation for finite elastoplasticity. Here, we attempt to place this Eulerian formulation on the thermodynamic grounds by extending it to a general case with thermal effects.

Abstract: Recently it has been demonstrated that, on the basis of the separation arising from the split of the stress power and two consistency criteria for objective Eulerian rate formulations, it is possible to establish a consistent Eulerian rate formulation of finite elastoplasticity in terms of the Kirchhoff stress and the stretching, without involving additional deformation-like variables labelled “elastic” or “plastic”. It has further been demonstrated that this consistent formulation leads to a simple essential structure implied by the work postulate, namely, both the normality rule for plastic flow and the convexity of the yield surface in Kirchhoff stress space. Here, we attempt to place such an Eulerian formulation on the thermodynamic grounds by extending it to a general case with thermal effects, where the consistency requirements are treated in a twofold sense. First, we propose a general constitutive formulation based on the foregoing separation as well as the two consistency criteria. This is accomplished by employing the corotational logarithmic rate and by incorporating an exactly integrable Eulerian rate equation for for thermo-elastic behaviour. Then, we study the consistency of the formulation with thermodynamic laws. Towards this goal, simple forms of restrictions are derived, and consequences are discussed. It is shown that the proposed Eulerian formulation is free in the sense of thermodynamic consistency. Namely, a Helmholtz free energy function in explicit form may be found such that the restrictions from the thermodynamic laws can be fulfilled with positive internal dissipation for arbitrary forms of constitutive functions included in the constitutive formulation. In particular, that is the case for the foregoing essential constitutive structure in the purely mechanical case. These results eventually lead to a complete, explicit constitutive theory for coupled fields of deformation, stress and temperature in thermo-elastoplastic solids at finite deformations. [Copyright &y& Elsevier]

No abstract.

The lower and upper Oldroyd rates are two well–known objective non–corotational rates. A remarkable property of these rates is that they establish direct relationships between finite strain measures and the Eulerian strain rate (stretching) D. Namely, the Oldroyd rates of the Almansi strain and the Finger strain, respectively, are exactly D. Here, we would like to study non–corotational rates of Oldroyd's type from a general point of view. We demonstrate that, for any given Hill's strain measure, there actually exist infinitely many definitions of non–corotational rates such that the rate of this strain evaluated according to each of these definitions is identical to D. A general explicit expression for the asymmetric second–order tensor defining all such non–corotational rates is derived in terms of the left Cauchy–Green deformation tensor and the velocity gradient. It is shown that a Hill–type non–corotational rate of any given Doyle–Ericksen or Seth–Hill strain can identically equal D. This markedly contrasts with a corresponding fact related to corotational rates. In a recent work, it has been established that, if a corotational rate of a strain is identical to D, there is only one choice under the doubly free choices of strain and spin, namely, Hencky's logarithmic strain and the logarithmic spin. The essence of this sharp contrast will be investigated from standpoints of both kinematics and rate constitutive formulations. In particular, relevant issues in traditional Eulerian rate formulations of finite elastoplasticity will be clarified by virtue of two consistency criteria that are essential to reasonable Eulerian rate formulations.

The microscopic mechanism of spontaneous polarization and refractive indices in 180° ferroelectric domain walls of tetragonal Barium titanate (BaTiO3) is discussed by using a microscopic model. This model bases on the orbital approximation in correlation with the dipole–dipole interaction due to the local field acting on all constituent ions within the domain wall. It is found that the behavior of both the spontaneous polarization and the refractive indices depends on the thickness of the domain wall which was varied between 5 and 20 Å. Moreover, the spontaneous polarization shows a hyperbolic tangent shape for domain walls of a larger thickness which then vanishes at the center of the domain wall. The refractive indices suggest the domain wall to act like a biaxial crystal resulting in refractive index profiles of a Gaussian shape for domain walls of ~20 Å. This dramatically affects optical transmission through the domain wall especially for light being polarized parallel to the domain wall.