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High intensity particle beams from accelerators induce high energy density states in bulk matter. The SIS-18 heavy ion synchrotron at GSI now routinely delivers intense Uranium beams that deposit about 1 kJ/g of specific energy in solid matter, e.g. solid lead. Due to the specific nature of the ion-matter interaction a volume of matter is heated uniformly with low gradients of temperature and pressure in the initial phase, depending on the pulse structure of the beam with respect to space and time. The new accelerator complex FAIR (Facility for Antiproton and ion Research) at GSI as well as beams from the CERN large hadron collider (LHC) will vastly extend the accessible parameter range for high energy density states. One special piece of accelerator equipment a superconducting high field dipole magnet, developed for the LHC at CERN is now serving as a key instrument to diagnose the dense plasma of the sun interior plasma, thus providing an extremely interesting combination of accelerator physics, plasma physics and astro-particle physics.

We present the analysis of Rossi X-ray Timing Explorer (RXTE) observations of the turn-on phase of a 35 day cycle of the X-ray binary Her X-1. During the early phases of the turn-on, the energy spectrum is composed of X-rays scattered into the line of sight plus heavily absorbed X-rays. The energy spectra in the 3–17 keV range can be described by a partial covering model, where one of the components is influenced by photoelectric absorption and Thomson scattering in cold material plus an iron emission line at 6.5 keV. In this paper we show the evolution of spectral parameters as well as the evolution of the pulse profile during the turn-on. We describe this evolution using Monte Carlo simulations which self-consistently describe the evolution of the X-ray pulse profile and of the energy spectrum.

We present pulse phase resolved spectra of the hypergiant high mass X-ray binary GX 301-2. We observed the source in 2001 October with RXTEcontinuously for a total on-source time of almost 200 ks. We model the continuum with both, a heavily absorbed partial covering model and a reflection model. In either case we find that the well known cyclotron resonant scattering feature (CRSF) at ~35 keV is – although present at all pulse phases – strongly variable over the pulse: the line position varies by 25% from 30 keV in the fall of the secondary pulse to 38 keV in the fall of the main pulse where it is deepest. The line variability implies that we are seeing regions of magnetic field strength varying between $3.4\times 10^{12}$G and $4.2\times 10^{12}$G.

Although they have not yet been detected, axions and axion-like particles (ALPs) continue to maintain the interest (even increasingly so) of the rare-event searches community as viable candidates for the Dark Matter of the Universe but also as a solution for several other puzzles of astrophysics. Their property of coupling to photons has inspired different experimental methods for their detection, one of which is the helioscope technique. The CERN Axion Solar Telescope (CAST) is the most sensitive helioscope built up to date and has recently published part of the latest data taken with the magnet bores gradually filled with 3He, probing the mass range up to 1.17 eV. The International AXion Observatory (IAXO) is being proposed as a facility where different axion studies can be performed, with the primary goal to study axions coming from the Sun. Designed to maximize sensitivity, it will improve the levels reached by CAST by almost 5 orders of magnitude in signal detection, that is more than one order of magnitude in terms of gaγ. Here we will summarize the most important aspects of the helioscopes, and focus mainly on IAXO, based on the recent papers [1, 2].

We present the XMM-Newtonfirst light image, taken in January 2000 with the EPIC pn camera during the instrument's commissioning phase, when XMM-Newtonwas pointing towards the Large Magellanic Cloud (LMC). The field is rich in different kinds of X-ray sources: point sources, supernova remnants (SNRs) and diffuse X-ray emission from LMCinterstellar gas. The observations are of unprecedented sensitivity, reaching a few 10$\sp{32}$erg/s for point sources in the LMC. We describe how these data sets were analysed and discuss some of the spectroscopic results. For the SNR N157Bthe power law spectrum is clearly steeper than previously determined from ROSAT and ASCA data. The existence of a significant thermal component is evident and suggests that N157Bis not a Crab-like but a composite SNR. Most puzzling is the spectrum of the LMChot interstellar medium, which indicates a significant overabundance of Ne and Mg of a few times solar.

The European Photon Imaging Camera (EPIC) consortium has provided the focal plane instruments for the three X-ray mirror systems on XMM-Newton. Two cameras with a reflecting grating spectrometer in the optical path are equipped with MOS type CCDs as focal plane detectors (Turner [CITE]), the telescope with the full photon flux operates the novel pn-CCD as an imaging X-ray spectrometer. The pn-CCD camera system was developed under the leadership of the Max-Planck-Institut für extraterrestrische Physik (MPE), Garching. The concept of the pn-CCD is described as well as the different operational modes of the camera system. The electrical, mechanical and thermal design of the focal plane and camera is briefly treated. The in-orbit performance is described in terms of energy resolution, quantum efficiency, time resolution, long term stability and charged particle background. Special emphasis is given to the radiation hardening of the devices and the measured and expected degradation due to radiation damage of ionizing particles in the first 9 months of in orbit operation.

We present XMM-Newtonobservations of the high redshift ($z=3.104$), radio-loud quasar PKS 0537-286. The EPIC CCD cameras provide the highest signal-to-noise spectrum of a high-zquasar to date. The EPIC observations show that PKS 0537-286 is extremely X-ray luminous ($L_{\rm X}=2$1047erg s-1), with an unusually hard X-ray spectrum ($\Gamma=1.27\pm0.02$). The flat power-law emission extends over the whole observed energy range (0.4 to 40 keV in the quasar rest frame); there is no evidence of intrinsic absorption, which has been claimed in PKS 0537-286 and other high zquasars. However, there is evidence for weak Compton reflection. A redshiftediron K line, observed at 1.5 keV - corresponding to ~6.15 keV in the quasar rest frame - is detected at 95% confidence. If confirmed, this is the most distant iron K line known. The line equivalent width is small (33 eV), consistent with the "X-ray Baldwin effect" observed in other luminous quasars. The reflected continuum is also weak ($R \la$0.25). We find the overall spectral energy distribution of PKS 0537-286 is dominated by the X-ray emission, which, together with the flat power-law and weak reflection features, suggests that the X-radiation from PKS 0537-286 is dominated by inverse Compton emission associated with a face-on relativistic jet.

Systems of quantities and units were introduced by Maxwell in the late 19th century. However, adapting these ideas for use in modern digital systems has proven difficult. We present an interpretation of units and dimensions that clarifies the main reasons for this difficulty. We then suggest how a central register of metrological information would support quantities and units. Digital systems that handle data may refer to this register to express measured quantities. This will resolve problems with ambiguity, delineate meaningful usage, and allow data to be rendered in familiar formats to people without compromising the underlying information content. We call the proposal a digital metrology layer, or M-layer. An M-layer expression has three components: 1) the kind of quantity, or aspect; 2) the value; and 3) the scale. The aspect and scale components appear in an expression as succinct references to information held in the central digital register. The M-layer notion of scale combines a measurement unit, or other type of reference, with information about the level of measurement. The notion of aspect extends the idea of kind of quantity, which plays an important role in unit systems.

An approximate method for estimating the drift of multibent structures is presented. Structures that are singly or doubly symmetrical in plan and comprising any combination of shear walls, coupled walls, rigid frames and braced frames, can be considered. Results for structures that are uniform with height compare closely with results from stiffness matrix computer analyses. The method is developed from coupledwall deflection theory which is expressed in terms of nondimensional structural parameters. The parameters involve three structural properties: the individual bending stiffness of the walls, the overall bending stiffness related to axial deformations of the walls and racking stiffness caused by reverse bending of the beams. Similar properties are calculated for rigid frames, braced frames and shear walls and then combined to determine values of the two parameters for the total structure. These values are then substituted into a generalized equation to obtain the deflection profile. This method accounts for axial deflection of the vertical components and is, therefore, more accurate for very tall structures. The method provides a rapid estimate of the drift in a highrise structure as well as allowing an easy means of comparing the suitability of different structural solutions for a tall building. The method also illustrates the fundamental dependence of the behavior of continuous type cantilevers on two characteristic parameters.

The lateral subvastus approach combined with an osteotomy of the tibial tubercle is a recognised, but rarely used approach for total knee replacement (TKR). A total of 32 patients undergoing primary TKR was randomised into two groups, in one of which the lateral subvastus approach combined with a tibial tubercle osteotomy and in the other the medial parapatellar approach were used. The patients were assessed radiologically and clinically using measurement of the range of movement, a visual analogue patient satisfaction score, the Western Ontario McMasters University Osteoarthritis Index and the American Knee Society score. Four patients were lost to the complete follow-up at two years.At two years there were no significant differences between the groups in any of the parameters for clinical outcome. In the lateral approach group there was one complication due to displacement of the tibial tubercle osteotomy and two osteotomies took more than six months to unite. In the medial approach group, one patient had a partial tear of the quadriceps. There was a significantly greater incidence of lateral patellar subluxation in the medial approach group (3 of 12) compared with the lateral approach group (0 of 16) (p = 0.034), but without any apparent clinical detriment.We conclude that the lateral approach with tibial tubercle osteotomy is a safe technique with an outcome comparable with that of the medial parapatellar approach for TKR, but the increased surgical time and its specific complications do not support its routine use. It would seem to be more appropriate to reserve this technique for patients in whom problems with patellar tracking are anticipated.

Achieving deep flexion after total knee replacement remains a challenge. In this study we compared the soft-tissue tension and tibiofemoral force in a mobile-bearing posterior cruciate ligament-sacrificing total knee replacement, using equal flexion and extension gaps, and with the gaps increased by 2 mm each. The tests were conducted during passive movement in five cadaver knees, and measurements of strain were made simultaneously in the collateral ligaments. The tibiofemoral force was measured using a customised mini-force plate in the tibial tray. Measurements of collateral ligament strain were not very sensitive to changes in the gap ratio, but tibiofemoral force measurements were. Tibiofemoral force was decreased by a mean of 40% (sd10.7) after 90° of knee flexion when the flexion gap was increased by 2 mm. Increasing the extension gap by 2 mm affected the force only in full extension. Because increasing the range of flexion after total knee replacement beyond 110° is a widely-held goal, small increases in the flexion gap warrant further investigation.

High intensity particle beams from accelerators induce high energy density states in bulk matter. The SIS-18 heavy ion synchrotron at GSI now routinely delivers intense Uranium beams that deposit about 1?kJ/g of specific energy in solid matter, e.g. solid lead. Due to the specific nature of the ion-matter interaction a volume of matter is heated uniformly with low gradients of temperature and pressure in the initial phase, depending on the pulse structure of the beam with respect to space and time. The new accelerator complex FAIR (Facility for Antiproton and ion Research) at GSI as well as beams from the CERN large hadron collider (LHC) will vastly extend the accessible parameter range for high energy density states. One special piece of accelerator equipment a superconducting high field dipole magnet, developed for the LHC at CERN is now serving as a key instrument to diagnose the dense plasma of the sun interior plasma, thus providing an extremely interesting combination of accelerator physics, plasma physics and astro-particle physics.

Current methods of measurement of proprioceptive function depend on the ability to detect passive movement (kinaesthesia) or the awareness of joint position (joint position sense, JPS). However, reports of proprioceptive function in healthy and pathological joints are quite variable, which may be due to the different methods used. We have compared the validity of several frequently used methods to quantify proprioception.Thirty healthy subjects aged between 24 and 72 years underwent five established tests of proprioception. Two tests were used for the measurement of kinaesthesia (KT1 and KT2). Three tests were used for the measurement of JPS, a passive reproduction test (JPS1), a relative reproduction test (JPS2) and a visual estimation test (JPS3).There was no correlation between the tests for kinaesthesia and JPS or between the different JPS tests. There was, however, a significant correlation between the tests for kinaesthesia (r = 0.86). We conclude therefore that a subject with a given result in one test will not automatically obtain a similar result in another test for proprioception. Since they describe different functional proprioceptive attributes, proprioceptive ability cannot be inferred from independent tests of either kinaesthesia or JPS.

Unit systems and dimensions emerged in the late 19th century. However, efforts to adapt these ideas for use in modern digital systems are proving a challenge. We provide an interpretation of units and dimensions that clarifies the main reasons for difficulties. We then suggest how a digital system would provide adequate support for quantities and units. A layer of metrological information is envisaged that would track details and allow familiar unit formats to be rendered. Three independent aspects of the data should be captured: 1) the quantity; 2) the measurement scale, scale type and conversion functions; and 3) the semantics of numerical data.

Twenty-three patients who had undergone unilateral patellectomy were tested using the Cybex II isokinetic dynamometer 9 years postoperatively. The results were compared with the performance of the uninvolved joint. There was a good correlation between loss of the quadriceps muscle function and loss of the hamstrings muscle function at 60 deg/s (R=0.7,P<0.001). Patients who showed a loss of quadriceps function of less than 40% also maintained good hamstrings function. A good or excellent functional result could be expected in these patients. If the loss of quadriceps function was more than 40%, a proportional loss of flexion torque was seen, indicating a functional impairment of the knee joint muscles not solely attributable to the loss of the lever arm. Furthermore, all patients with a loss of peak flexion torque of more than 30% showed an unsatisfactory clinical result. The evaluation of the hamstrings muscles by measuring the peak flexion moment at 60 deg/s can therefore be used as a preoperative assessment and as a guideline for rehabilitation after patellectomy.

Estimates of knee joint loadings were calculated for 12 normal subjects from kinematic and kinetic measures obtained during both level and downhill walking. The maximum tibiofemoral compressive force reached an average load of 3.9 times body-weight (BW) for level walking and 8 times BW for downhill walking, in each instance during the early stance phase. Muscle forces contributed 80% of the maximum bone-on-bone force during downhill walking and 70% during level walking whereas the ground reaction forces contributed only 20% and 30% respectively.Most total knee designs provide a tibiofemoral contact area of 100 to 300 mm2. The yield point of these polyethylene inlays will therefore be exceeded with each step during downhill walking. Future evaluation of total knee designs should be based on a tibiofemoral joint load of 3.5 times BW at 20° knee flexion, 8 times BW at 40° and 6 times BW at 60°.

Accelerated rehabilitation after anterior cruciate ligament (ACL) reconstruction has become increasingly popular. Methods employed include immediate extension of the knee and immediate full weight bearing despite the risks presented by a graft pull-out fixation strength of 200–500 N. The purpose of this study was to calculate the tibiofemoral shear forces and the dynamic stabilising factors at the knee joint for the reasonably demanding task of downhill walking, in order to determine whether or not this task presented a postoperative risk to the patient. Kinematic and kinetic data were collected on six male and six female healthy subjects during downhill walking on a ramp with a 19% gradient. Planer net joint moments and mechanical power at the knee joint were calculated for the sagittal view using a force platform and videographic records together with standard inverse dynamics procedures. A two-dimensional knee joint model was then utilised to calculate the tibiofemoral shear and compressive forces, based on the predictions of joint reaction force and net moment at the knee. Linear envelopes of the electromyographic (EMG) activity recorded from the rectus femoris, gastrocnemius and biceps femoris muscles were also obtained. The maximum tibiofemoral shear force occurred at 20% of stance phase and was, on average, 1.2 times body weight (BW) for male subjects and 1.7 times BW for female subjects. The tibiofemoral compressive force was 7 times BW for males and 8.5 times BW for females during downhill walking. The hamstring muscle showed almost continuous activity throughout the whole of the stance phase. The gastrocnemius muscle had its main activity at heelstrike, with a second brust during the late stance phase. Knee joint shear force predictions of approximately 1000 N for a 70-kg subject greatly exceed the strength of a typical ACL graft fixation and muscular stabilisation of the knee is therefore vital to joint integrity. The hamstring muscle shows almost continuous activity during the stance phase and thereby affords some stability, but the gastrocnemius is also seen to be an important stabiliser of the knee joint in the presence of increased shear forces during early stance. Associated stability to the knee joint is indicated by compressive loadings of 7–8 times BW across the tibiofemoral joint. Whereas under normal circumstances there is sufficient dynamic joint stabilisation during downhill walking, the muscular impairment often arising postoperatively from disturbed proprioception could endanger an ACL graft. Therefore downhill walking should be avoided during the postoperative phase in order to protect the reconstruction.

Zusammenfassung: Das neue Inhalationsan�sthetikum Desfluran besitzt sehr niedrige Blut-Gas- und Gewebe-Blut-Verteilungskoeffizienten und l��t so raschere Ein- und Ausleitungszeiten erwarten. In der vorliegenden Phase-III-Studie wurden Aufwachverhalten und H�modynamik unter Desfluran und Isofluran prospektiv randomisiert verglichen. Untersucht wurden 49 chirurgische Patienten (Desfluran n=24, Isofluran n=25) in balancierter An�sthesietechnik: orale Pr�medikation mit 7,5 mg Midazolam; Einleitung mit 0,1 mg Fentanyl und 5 mg/kg Thiopental; Narkosebeatmung mit Desfluran 0,5–18 bzw. Isofluran 0,2–3,0 Vol%, jeweils in 50% N 2 O. Bei den h�modynamischen Parametern ergaben sich keine wesentlichen Unterschiede. Zwei Patienten reagierten nach rascher Erh�hung der Desfluran-Vapor-Einstellung mit Blutdruck- und Herzfrequenzanstieg. Diese Reaktion lie� sich bei allen weiteren Patienten durch langsame Dosissteigerung vermeiden. Nach An�sthesie-Ende flutete Desfluran signifikant schneller ab als Isofluran (F A /F A0 ). Trotzdem zeigten die Aufwachzeiten keinen signifikanten Unterschied (Augen�ffnen jeweils nach 12 min), vermutlich bedingt durch die angewandte balancierte An�sthesietechnik, die durch gleichzeitigen Einsatz mehrerer An�sthetika zum Profilverlust der Einzelsubstanz f�hren kann. Zusammengefa�t ergibt sich, da� Desfluran als Hauptkomponente einer balancierten An�sthesie unter den Gesichtspunkten Steuerbarkeit und h�modynamische Stabilit�t f�r chirurgische Eingriffe ebenso geeignet erscheint wie Isofluran. Mit einem rascheren Erwachen ist aber bei der balancierten An�sthesietechnik nicht zwangsl�ufig zu rechnen.

Objective.To analyse and compare the shape of wear particles found in healthy and osteoarthritic human knee joints for monitoring the progress of osteoarthritis, the long-term prognosis and to evaluate therapeutic regimens.
Method.Joint particles from seven patients with normal cartilage in all compartments of the knee joint, 12 patients with thickness (grade 2) and four patients with erosions down to bone (grade 3) were analysed. A total of 565 particles were extracted from synovial fluid samples by ferrography and analysed in a scanning electron microscope. A number of numerical descriptors, i.e. boundary fractal dimension, shape factor, convexity and elongation, were calculated for each particle image and correlated to the degree of osteoarthritis using non-parametric tests.
Results.Experiments demonstrated that there were significant differences between the numerical descriptors calculated for wear particles from healthy and osteoarthritic knee joints (P&lt;0.01), suggesting that the particle shape can be used as an indicator of the joint condition. In particular, the fractal dimension of the particle boundary was shown to correlate directly with the degree of osteoarthritis.
Conclusion.Numerical analysis of the shape of wear particles found in human knee joints may provide a reliable means for the assessment of cartilage repair after surgical or conservative treatment of osteoarthritis.
Keywords:Wear particles, Numerical descriptors, Synovial joints, Osteoarthritis, Ferrography

Twenty-three patients who had undergone unilateral patellectomy were tested using the Cybex II isokinetic dynamometer 9 years postoperatively. The results were compared with the performance of the uninvolved joint. There was a good correlation between loss of the quadriceps muscle function and loss of the hamstrings muscle function at 60 deg/s (R=0.7,P<0.001). Patients who showed a loss of quadriceps function of less than 40% also maintained good hamstrings function. A good or excellent functional result could be expected in these patients. If the loss of quadriceps function was more than 40%, a proportional loss of flexion torque was seen, indicating a functional impairment of the knee joint muscles not solely attributable to the loss of the lever arm. Furthermore, all patients with a loss of peak flexion torque of more than 30% showed an unsatisfactory clinical result. The evaluation of the hamstrings muscles by measuring the peak flexion moment at 60 deg/s can therefore be used as a preoperative assessment and as a guideline for rehabilitation after patellectomy.

A 59-year-old woman with calcific tendinitis in her right shoulder underwent extracorporeal shock-wave lithotripsy. Three years and four months later she presented with osteonecrosis of the head of the right humerus. It is known that shock waves in patients with urological disorders can damage blood vessels. A possible reason for the development of osteonecrosis in this patient may have been damage to the blood supply of the head of the humerus.

Bridge engineering world practice has showed that implicit method of service life prediction, relying on sufficient quality and depth of concrete cover, do not guarantee a 100- year structure lifetime without major, complex and expensive repair works. Bridges exposed to harsh combination of mechanical (static, dynamic, cyclic loading) and environmental (sea salts, de-icing agencies, freeze - thawing cycles, etc.) actions are particularly vulnerable. Two such case studies: Krk Bridge and Maslenica Bridge located in aggressive maritime environment will be analysed in the paper including in-service performance and comparison between measured values on bridges and numerical results obtained by two numerical models for service life prediction: the 3D chemo-hygro-thermo mechanical (3D CHTM) model implemented into the finite element code MASA and the Life-365 model. Both models are capable to realistically predict chloride content in concrete after long-term exposure to seawater. However, the 3D CHTM model, which considers cracks and damage in concrete, anticipates the beginning of steel reinforcement depassivation much more precisely than the other model which doesn't take concrete damage and cracks into account.

Concrete damage (cracks, voids and delamination) significantly influence initiation and propagation phase of reinforcement corrosion. The three methods are combined in the framework of this research: (i) on-site testing on concrete bridges, (ii) application of an advanced numerical model for service life prediction on existing structures and (iii) laboratory experiments on permeability of cracked concrete. The aim of this research is to determine the mutual interaction of material, structural, environmental and climate performance indicators under following degradation mechanisms: chloride induced corrosion of reinforcement in concrete and concrete cracking due to mechanical and non-mechanical loading. The broader aim is to predict bridge service life more precisely as a base for establishment of an optimal bridge quality control plan. The focus of the paper is application of on-site testing on existing bridges. Influence of cracks in concrete on reinforcement corrosion on existing structures can be determined by application of non-destructive testing, not only by measured values but also to define area of structure on which a crack has impact.