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An elastoviscoplastic constitutive equation is proposed to describe both the elastic and rate-dependent plastic deformation behavior of Carbopol® dispersions, commonly used to study yield-stress fluids. The model, a variant of the nonlinear Maxwell model with stress-dependent relaxation time, eliminates the need for a separate Herschel–Bulkley yield stress. The stress dependence of the viscosity was determined experimentally by evaluating the steady-state flow stress at a constant applied shear rate and by measuring the steady-state creep rate at constant applied shear stress. Experimentally, the viscosity's stress-dependence was confirmed to follow the Ree–Eyring model. Furthermore, it is shown that the Carbopol® dispersions used here obey time-stress superposition, indicating that all relaxation times experience the same stress dependence. This was demonstrated by building a compliance mastercurve using horizontal shifting on a logarithmic time axis of creep curves measured at different stress levels and by constructing mastercurves of the storage- and loss-modulus curves determined independently by orthogonal superposition measurements at different applied constant shear stresses. Overall, the key feature of the proposed constitutive equation is its incorporation of a nonlinear stress-activated change in relaxation time, which enables a smooth transition from elastic to viscous behavior during start-up flow experiments. This approach bypasses the need for a distinct Herschel–Bulkley yield stress as a separate material characteristic. Additionally, the model successfully replicates the observed steady-state flow stress in transient-flow scenarios and the steady-state flow rate in creep experiments, underlining its effectiveness in capturing the material's dynamic response. Finally, the one-dimensional description is readily extended to a full three-dimensional finite-strain elastoviscoplastic constitutive equation. [ABSTRACT FROM AUTHOR]

This article, published in the journal Neuropediatrics, examines the potential use of inflammatory cytokines and peripheral blood mononuclear cell (PBMC) populations as biomarkers for disease activity in children with tuberous sclerosis complex (TSC)-related refractory epilepsy. The study found that TSC patients had varying neurocognitive phenotypes and received more antiseizure medication than the control group. Additionally, TSC patients had higher seizure frequencies and elevated levels of the inflammatory cytokine TNF-α and CD4 cell counts. The authors suggest that further research is needed to determine the role of cytokines as biomarkers for refractory TSC-related epilepsy. [Extracted from the article]

The neural correlates of most cognitive functions in fish are unknown. This project aimed to identify brain regions involved in visual learning in the cichlid fish Pseudotropheus zebra. The expression of the protein pS6 was measured in 19 brain areas and compared between groups of individuals subjected to four different behavioral contexts (control, avoidance, trained, and novelty groups). Control group individuals were sacrificed with minimal interactions. Fish in the avoidance group were chased with a net for an hour, after which they were sacrificed. Individuals in the trained group received daily training sessions to associate a visual object with a food reward. They were sacrificed the day they reached learning criterion. Fish in the novelty group were habituated to one set of visual stimuli, then faced a change in stimulus type (novelty stimulus) before they were sacrificed. Fish in the three treatment groups showed the largest activation of pS6 in the inferior lobes and the tectum opticum compared to the control group. The avoidance group showed additional activation in the preoptic area, several telencephalic regions, the torus semicircularis, and the reticular formation. The trained group that received a food reward, showed additional activation of the torus lateralis, a tertiary gustatory center. The only area that showed strong activation in all three treatment groups was the nucleus diffusus situated within the inferior lobe. The inferior lobe receives prominent visual input from the tectum via the nucleus glomerulosus but so far, nothing is known about the functional details of this pathway. Our study showed for the first time that the inferior lobes play an important role in visual learning and object recognition. [ABSTRACT FROM AUTHOR]

Carbonate rocks of the Triassic deposits of the South Mangyshlak basin are investigated in this paper for their boundary values, which are important for interpretation of field geophysical data as well as perforation and blasting. Based on their lithological composition, Triassic deposits are classified as either terrigenous or carbonate reservoirs. Carbonate reservoirs are found in the Middle Triassic strata containing volcanogenic dolomite and volcanogenic limestone rocks. A complex type of reservoir characterizes these rocks: porous-fractured, porouscavernous, and fractured. Upper Triassic sediments are formed by the intercalation of tuffaceous, siltstone-sandy, and mudstone rocks overlying Middle Triassic sedimentary rocks. Oil deposits are confined to polymictic sandstones, which are oil-saturated to varying degrees. In order to substantiate the quantitative criteria of the reservoir, experimental studies of the core samples were carried out in the laboratory. Fluid flow studies were performed where physical and hydrodynamic characteristics were determined when oil was displaced by displacing reagents. On the basis of the parameters obtained, correlations between reservoirs and non-reservoirs were constructed. Based on relationships between reservoir properties such as porosity and permeability versus residual water content, as well as effective porosity and permeability versus dynamic porosity, the boundary values were determined. Using these results, the porosity limit for the Middle and Upper Triassic strata has been determined to be 7%, the permeability limit for the Middle Triassic has been determined to be 0.02 X 10-3 µm², and the permeability limit for the Upper Triassic has been determined to be 0.3 X 10-3 µm² . [ABSTRACT FROM AUTHOR]

Arc welding generally introduces undesired local residual stress states on engineering components hindering high-quality performance in service. Common procedures to reduce the tensile residual stresses are post-heat treatments or mechanical surface treatments like hammering or shot-peening. Assessments of residual stress profiles of post-weld treatments underneath the weld surface are essential, especially in high safety exigency systems like pressure vessels or piping at power plants. In this study, neutron diffraction is used to determine the stress profile after finish milling of an austenitic steel weld in order to verify a chained finite element simulation predicting the final residual stress fields including milling and welding contributions. Non-destructive measurements with spatial resolutions of less than 0.2 mm within the first 1 mm from the surface were mandatory to confirm the finite element simulations of the coarse-grained austenitic material. In the data analysis procedure, the obtained near-surface data have been corrected for spurious strain effects whenever the gauge volume was partially immersed in the sample. Moreover, constraining the surface data to values obtained by x-ray diffraction and data deconvolution within the gauge volume enabled access of the steep residual stress profile within the first 1 mm. [ABSTRACT FROM AUTHOR]

To know the residual stress state within a component is essential for predicting its service life time. Neutron diffraction is a reliable tool for non-destructive determination of macroscopic residual stresses, even deep inside a component. One standard procedure in neutron residual stress analysis is to cut out small macrostress free coupons from the strained component, which serve as reference samples. Redistribution of intergranular stresses due to relaxation when the coupon is cut out, however, may lead to spurious macroscopic stresses. A quantitative study of the change of intergranular stresses shows that, contrary to conventional thought, even the {311} Bragg reflection is affected strongly by this phenomenon. In this case, the use of reference values calculated using boundary conditions of mechanical equilibrium enables to extract reliable macroscopic residual stress values. [ABSTRACT FROM AUTHOR]

Objective: To confirm the robustness and validity of an automatic scoring system, algorithm‐based, that grades the severity of nine facial signs through "selfies" smartphones pictures taken by European Caucasian women through dermatological assessments. Methods: 157 Caucasian women from three countries (France, Germany, Spain), of different ages (20–75 years), took one "selfie" image by the frontal camera of their smartphones whereas local dermatologists photographed them with the back camera of the same smartphone. The same nine facial signs of these subjects were initially graded by these local dermatologists, using referential Skin Aging Atlases. All 314 "selfies" images were then further automatically analyzed by the algorithm. The severity of facial signs (wrinkles, pigmentation, ptosis, skin folds etc.) were statistically compared to the assessments made by the three dermatologists, taken as ground truth. Results: Highly significant coefficients of correlation (P < 0.001) were found in the three cohorts between the grades provided by the system and those from dermatologists in live. The back camera – of a better resolution than the frontal one – seems affording slightly more significant correlations. However, although significantly correlated, the signs of vascular disorders and cheek skin pores present some disparities that are likely linked to the technical diversity of smartphones or self‐shootings, leading to lower coefficients of correlations. Conclusion: This automatic scoring system offers a promising approach in the harmonization of Dermatological assessments of skin facial signs and their changes with age or the follow up of anti‐aging treatments. [ABSTRACT FROM AUTHOR]

A method for near-surface strain scanning measurements using neutron diffraction with large gauge volumes is described. The approach corrects for pseudo (spurious) strains related to partially illuminated gauge volumes and enables deconvolution of the large gauge volume measurements into the assumed real profile. It was validated against X-ray and neutron diffraction experiments with very high spatial resolution. The analysis of the results shows that neutron diffraction based strain measurements with standard (or large) sized gauge volumes are possible to reproduce the real strain profile free of artificial effects related to partial illumination. Compared to measurements with smaller gauge volumes gains in counting time of up to a factor of fifteen can be achieved without appreciable loss in spatial resolution. • Non-destructive neutron strain profiles assessment from the surface to bulk • Neutron fast and high spatial resolved strain profiles analysis • Correction of through neutron surface strain profile from spurious strains • Deconvolution of measured strain profile within neutron gauge volume • Assessment of intrinsic strain profile after manufacturing process from the surface [ABSTRACT FROM AUTHOR]

The currently available field-cycling NMR relaxometers still suffer from a rather narrow frequency range; they facilitate measurements of the 1H spin-lattice relaxation rate in the frequency of 10 kHz-30 MHz. This limit may be overcome by constructing master curves via exploiting frequency-temperature superposition, the latter being an intrinsic feature of the collective dynamics in many soft matter systems. It states that the shape of the motional time-correlation function is essentially temperature independent over a large temperature interval. As will be demonstrated, master curves may be built in the susceptibility or the spectral density representation of spin-lattice relaxation data. As a result, the effective frequency range is expanded up to ten decades, and the applied shift factors provide the temperature dependence of the corresponding correlation time. Three examples are presented: cyano adamantane in its plastically crystalline phase, the liquid glycerol, and the melt of poly(ethylene propylene). Advantages and limitations of the approach are discussed. [ABSTRACT FROM AUTHOR]

Recently the anti-Stokes spectroscopy after strong vibrational excitation via resonant absorption was rediscovered, for the study of population relaxation dynamics. A closer theoretical inspection of this experimental approach reveals that properly chosen polarization conditions allow the study of molecular reorientational motion. Furthermore the sign of a/γ (the invariants of the Raman polarizability tensor) can be determined. Experimental data for chlorinated alkanes will be presented. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Energy resolved photodissociation studies of CO3-·(H2O)n, n=1,2,3 are reported for photon energies ranging from 1.95 to 2.2 eV. The only dissociation channel observed is the loss of all attached water molecules to give unclustered CO3- as the sole photofragment ion. The cross section for this mechanism is substantially higher than that for the bare ion, and the sharp structure observed in the spectrum of the bare ion is nearly lost in the clusters. Analysis of the kinetic energy distributions for the photofragment ions places an upper limit of 20 μs on the lifetime of the excited clusters, and demonstrates that approximately 95% of the excess energy in the cluster remains in the CO3- containing fragment rather than being partitioned into relative translation of the photofragments or into internal motion of the water fragments. The dissociation mechanism begins with a bound–bound 2A1←2B1 transition within the core CO3- ion. Internal conversion returns the core ion to the electronic ground state with substantial vibrational excitation; redistribution of this vibrational energy results in vibrational predissociation of the cluster. The relations of this mechanism to those that occur in the bare ion and to other vibrational predissociation experiments on clusters are discussed. [ABSTRACT FROM AUTHOR]

The dynamics of CO3- photodissociation is studied with a new photodissociation spectrometer that allows kinetic energy-resolved detection of parent ions and photofragments. Kinetic energy release distributions, photodissociation spectra, and the dependence of the photofragment intensity on the laser power and background pressure are presented. Photodissociation of CO3- in the energy range 1.95–2.2 eV leads to CO2+O- fragments, and is found to occur by two distinct mechanisms. These mechanisms involve three electronic states that correlate with CO2+O-—the 2B1 ground state, a 2A1 weakly bound state, and a repulsive 2B2 state. The first mechanism begins with a low cross section 2A1 ← 2B1 transition that gives structure to the spectra. From this intermediate state, a second photon carries the ion to the 2B2 state. Dissociation to the observed photofragments occurs rapidly on the repulsive surface. In this two photon mechanism, at least 20% of the available energy is disposed of in relative translation of photofragments. The second mechanism is also initiated by the 2A1 ← 2B1 transition. Deexcitation of the 2A1 bound state by internal conversion, however, leads to high lying vibrational levels of the ground 2B1 state. These vibrational levels are found to have an enhanced collision-induced dissociation cross section. [ABSTRACT FROM AUTHOR]

Highlights • An energy based bifurcation analysis determines the diameter of columnar joints. • Derivatives of the energy are calculated via 3D FEM simulation. • A Fourier series expansion of the crack front reduces the number of unknowns. • Symmetries in the ideal hexagonal pattern reduces the size of the model. Abstract During the shrinkage of volcanic rock, columnar joints evolve with an almost regular hexagonal pattern formation and a very distinct column diameter defining the crack spacing. This phenomenon is caused by an inhomogeneous, constantly moving temperature field. The constant column growth is presumably always close to a bifurcation point at which the ideal regular pattern of hexagons could branch off to a pattern with a different symmetry due to slightly changing cooling conditions. This paper presents an energy-based fracture mechanical bifurcation analysis to determine this point and its stability by evaluating first and second order derivatives of the free Helmholtz energy with respect to a limited number of coefficients of a truncated Fourier series expansion of the three-dimensional crack front contour. The energy is obtained by linear elastic simulations on three-dimensional Finite Element models of the periodically repeatable patterns before and after bifurcation. While providing an understanding of the column growth procedure of volcanic rock, the characteristics of the approach suggest applications for various complex three-dimensional crack growth systems in engineering. [ABSTRACT FROM AUTHOR]

A combined study of neutron diffraction and difference dilatometry on submicrocrystalline Ni prepared by high pressure torsion aims at studying the anisotropic behaviour during dilatometry and its relation to internal stress and structural anisotropy. Macroscopic stresses were undetectable in the dilatometer samples. Along with specific tests such as post cold-rolling, this shows that an observed anisotropic length change upon annealing is not caused by internal stress, but can be explained by the inherent microstructure, i.e. the anisotropic annealing of relaxed vacancies at grain boundaries of shape-anisotropic crystallites. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structures of the quaternary rare-earth intermetallic compound Nd3Co29Si4B10 have been investigated by neutron diffraction (1.5 and 300 K). Rietveld refinements demonstrate that Nd3Co29Si4B10 is isostructural with the Nd3Ni29Si4B10 tetragonal structure and that Nd3Co29Si4B10 has a canted magnetic structure below the ferromagnetic ordering temperature TC =200 K. The refinement of the 1.5-K diffraction pattern leads to mean values for the magnetic moments of μCo∼0.4μB and μNd,2μB at the 2b and 4d sites. [ABSTRACT FROM AUTHOR]

The effects of applied hydrostatic pressure on the structural and magnetic behavior of ferromagnetic LaMn[sub 2] Si[sub 2] of tetragonal I4/m m m structure have been investigated by x-ray diffraction (0-4.1 GPa) and neutron diffraction (0-6.1 GPa) measurements. We have observed a pressure-induced ferromagnetic to antiferromagnetic transition at ∼ 6.1 GPa in LaMn[sub 2]Si[sub 2] by neutron diffraction. [ABSTRACT FROM AUTHOR]

Background: Tuberous sclerosis complex (TSC) is a rare multisystem disorder caused by mutations in the TSC1 or TSC2 gene. More than 90% of patients with TSC develop neurological and/or neuropsychiatric manifestations. The aim of the present study was to determine the developmental and cognitive long-term outcomes of pediatric TSC patients. Methods: This cross-sectional, monocenter study included pediatric TSC patients who received multidisciplinary long-term care with a last visit between 2005 and 2019. Neurological manifestations and cognitive development (BSID, K-ABC) were analyzed in relation to age and type of mutation. Results: Thirty-five patients aged 13.5 ± 7.8 years were included in the study. Diagnosis was confirmed genetically in 65.7% of patients (TSC1, 26.1%; TSC2, 65.2%; NMI, 8.7%). Mean age at diagnosis was 1.3 ± 3.5 years; 74.3% of the patients had been diagnosed within the first year of life due to seizures (62.9%) or/and cardiac rhabdomyomas (28.6%). The most common TSC manifestations included structural brain lesions (cortical tubers, 91.4%; subependymal nodules, 82.9%), epilepsy (85.7%), and cardiac rhabdomyomas (62.9%). Mean age at seizure onset was 1.5 ± 2.3 years, with onset in 80.0% of patients within the first two years of life. Infantile spasms, which were the first seizure type in 23.3% of the patients, developed earlier (0.6 ± 0.4 years) than focal seizures (1.8 ± 2.5 years). Refractory epilepsy was present in 21 (70.0%) patients, mild or severe intellectual impairment in 66.6%, and autism spectrum disorders in 11.4%. Severe cognitive impairment (33.3%) was significantly associated with epilepsy type and age at seizure onset (p < 0.05). Conclusions: The results emphasized the phenotypic variability of pediatric-onset TSC and the high rate of neurological and neuropsychiatric morbidity. Early-onset refractory epilepsy was associated with impaired cognitive development. Children of all ages with TSC require multidisciplinary long-term care and individual early-intervention programs. [ABSTRACT FROM AUTHOR]

The dynamics of melts of linear poly(ethylene-alt-propylene) (PEP) of different molar masses (M) is investigated by 1H field-cycling (FC) NMR relaxometry. Employing a commercial and a home-built relaxometer the spin-lattice relaxation rate R1(ω) is measured in the frequency range of 200 Hz to 30 MHz and the temperature range of 200-400 K. Transforming the FC NMR relaxation data to the susceptibility representation and applying frequency-temperature superposition, master curves for the dipolar correlation function CDD(t/τα) (containing intra- and intermolecular contributions) are constructed which extend up to six decades in amplitude and eight in time. Here, τα is the time scale of the structural (α-) relaxation, which is obtained over several decades. Comparison with previously reported FC data for polybutadiene (PB) discloses very similar CDD(t). Depending on M, all the five relaxation regimes of a polymer melt are covered: in addition to the α-process (0) and the terminal relaxation (IV), which are immanent to all liquids, three polymer-specific power-law regimes (Rouse, I; constraint Rouse, II; and reptation, III) are found, i.e. CDD(t) ∝ t-ε. The corresponding exponents (εI-III) are close to those predicted by the tube-reptation (TR) model for the segmental translation. In contrast to previous interpretation the intermolecular relaxation dominates CDD(t), in particular in regime II and beyond. The decomposition into intra- (mediated by segmental reorientation) and intermolecular relaxation (mediated by segmental translation) via isotope dilution experiments yields Cinter(t) = Ctrans(t) ∝ t-0.28±0.05 concerning PEP and Cinter(t) ∝ t-0.30±0.05 concerning PB for regime II (high-M limit). For the reorientational correlation function Cintra(t) = C2(t) ∝ t-0.50±0.05 (PEP) and C2(t) ∝ t-0.45±0.05 (PB) are obtained. These exponents εIIintra are at variance with εIITR = 0.25 predicted by the TR model. The fact that translation conforms to the TR model, while reorientation does not, now confirmed for the two polymers PEP and PB, challenges de Gennes' return-to-origin hypothesis which assumes strong translational-rotational coupling in the TR model. [ABSTRACT FROM AUTHOR]

String-pulling is a widely used paradigm in animal cognition research to assess what animals understand about the functionality of strings as a means to obtain an out-of-reach reward. This study aimed to systematically investigate what rules Western scrub-jays ( Aphelocoma californica) use to solve different patterned string tasks, i.e. tasks in which subjects have to choose between two or more strings of which only one is connected to the reward, or where one is more efficient. Arranging strings in a parallel configuration showed that the jays were generally capable of solving multiple-string tasks and acted in a goal-directed manner. The slanted and crossed configurations revealed a reliance on a 'proximity rule', that is, a tendency to choose the string-end closest to the reward. When confronted with strings of different lengths attached to rewards at different distances the birds chose according to the reward distance, preferring the reward closest to them, and were sensitive to the movement of the reward, but did not consistently prefer the shorter and therefore more efficient string. Generally, the scrub-jays were successful in tasks where the reward was closest to the string-ends they needed to pull or when string length and reward distance correlated, but the birds had problems when the wrong string-end was closest to the reward or when the food items were in close proximity to each other. These results show that scrub-jays had a partial understanding of the physical principles underlying string-pulling but relied on simpler strategies such as the proximity rule to solve the tasks. [ABSTRACT FROM AUTHOR]

Proton (¹H) field-cycling (FC) NMR relaxometry is applied to monitor the crossover in the segmental subdiffusion from the Rouse to the constrained Rouse regime in an entangled linear polymer melt. The method probes the dispersion of the spin-lattice relaxation rate R1(ω). Via Fourier transformation the segmental mean square displacement ⟨r²(t)⟩ is calculated from the intermolecular relaxation contribution R1inter(ω) to the total ¹H spin-lattice relaxation dispersion R1(ω). As an example we chose poly(ethylene propylene) (M = 200k), and R1inter(ω) is singled out by performing an isotope dilution experiment. The ⟨r²(t)⟩ data obtained by FC NMR is directly compared to such of neutron scattering (NS) available from the literature. Because of different experimental time windows the NS data is converted to a reference temperature assuming frequency-temperature superposition. Absolute agreement is revealed between FC NMR and NS. The data on ⟨r²(t)⟩ confirm the predictions of the tube-reptation model; i.e., the crossover from Rouse regime to constraint Rouse regime is identified, and the tube diameter is estimated to d ≈ (4.6 ± 0.2) nm. Thus, ¹H FC NMR has established itself as an alternative route to access subdiffusion. [ABSTRACT FROM AUTHOR]

In this paper we report about the formation of intergranular strains in superalloy Haynes 282 studied by neutron diffraction during uniaxial tensile testing. The results gained from the initial bar material are compared to results of a peak-aged sample state at ambient temperature. A comparison of the results with data from a fully aged IN 718 alloy sample shows that intergranular strains are much lower in Haynes 282 than in the conventional nickel based superalloy. In contrast to IN 718 the formation of intergranular residual strains between bar material and heat treated sample state shows no significant differences. The relevance of the results to the macroscopic residual stress analysis by neutron diffraction on both continuous wavelength and spallation neutron sources is discussed in detail. [ABSTRACT FROM AUTHOR]

Background Psoriasis has a negative impact on patient's' quality of life, which may reflect the physical and psychosocial impact of the disease. However, little is known about the perceived burden of disease. Pictorial Representation of Illness and Self Measure (PRISM), a pictorial tool, was developed to measure this global suffering. Capturing quality of life impairments in psoriasis is an integral part of assessing the overall disease severity and planning effective treatment strategies. Objective To validate Pictorial Representation of Illness and Self Measure (PRISM) in psoriasis patients. Methods An investigator initiated, prospective cohort study was performed in 108 outpatients with psoriasis to validate PRISM as an appropriate tool; Reliability was assessed in a cohort with controlled stable disease, repeated after 1 hour and after a 3-month follow-up phase; Convergent validity determined by correlation against measures of life quality (DLQI) and reported severity of psoriasis (PASI, PGA and BSA) was performed. Results For PRISM, we found a high reliability for short-term measurements (ICC = 0.98, P < 0.001) and for follow-up assessments at 3 months (ICC = 0.76, P < 0.001). Our investigation showed significant differences between patients with clear to minimal (PGA 0, 1), mild (PGA 2) and moderate-to-severe disease (PGA 3, 4) and significant (P < 0.001) correlation with DLQI, PGA, PASI and BSA (ρ = -0.62, -0.54, -0.44 and -0.39 respectively). Conclusion PRISM is a highly reliable tool and new approach to assess perceived burden of patients with psoriasis. It is easy to use and we recommend the application as an additional outcome measure in clinical trial settings. [ABSTRACT FROM AUTHOR]

Field-cycling and field-gradient 1H NMR experimentswere combined to reveal the segmental mean-square displacement asa function of time for polydimethylsiloxane (PDMS) and polybutadiene(PB). Together, more than 10 decades in time are covered, and allfour power-law regimes of the tube-reptation (TR) model are identifiedwith exponents rather close to the predicted ones. Characteristicpolymer properties like the tube diameter a0, the Kuhn length b, the mean-square end-to-enddistance ⟨R02⟩, the segmental correlation timeτs(T), the entanglement time τe(T), and the disengagement time τd(T) are estimated from the measurements andcompared to results from literature. Concerning τd(T), fair agreement is found. In the case of τe, agreement with rheological data is achieved when the timeconstant is extracted from the minimum in the shear modulus G″(ω). Concerning the TR predictions the molarmass (M) dependence of τdis essentiallyreproduced. Yet, calculating τefrom τdfor PDMS yields agreement with experimental data while forPB it gets by 2 orders of magnitude too short. In no case τeis correctly reproduced from τs(T). Segmental and shortest Rouse times appear to coincidefor PB, while in the case of PDMS the latter turns out to be longerby 1 decade. [ABSTRACT FROM AUTHOR]

The differences in timing in bud burst between species have been interpreted as an adaptation to late frost events in spring. Thus, it has been suggested that the degree of frost susceptibility of leaves is species-specific and depends on the species' phenology and geographic distribution range. To test for relationships between frost tolerance and phenology as well as between frost tolerance and distribution range across Central European tree species, we studied the frost hardiness of closed buds before bud burst and of freshly opened buds at the time of bud burst. We hypothesized that species with early bud burst and species distributed in eastern and northern areas were more frost tolerant than species with late bud burst and species distributed in western and southern areas. Frost hardiness was estimated by exposing twigs to 11 frost temperatures between −4°C and −80°C and by assessing tissue damage by the electrolyte leakage method. In contrast to our hypotheses, neither frost hardiness of closed buds nor frost hardiness of freshly opened buds were related to any variable describing species' macroclimatic niche. Furthermore, frost hardiness of freshly opened buds did not differ among species. Thus, the investigated species with early bud burst take higher risks of frost damage than the species with late bud bursts. These findings indicate that frost hardiness might not play the key role in limiting the geographic distribution ranges previously anticipated. [ABSTRACT FROM AUTHOR]

Field-cycling (FC) 1Hand 2H NMR relaxometry is applied to linear polybutadiene(PB) of different molar mass (M) in order to testcurrent polymer theories. Applying earth field compensation, fivedecades in the frequency dependence of the spin–lattice relaxationrate T1–1(ν) = R1(ν) are accessed (200 Hz - 30 MHz), and we focus on thecrossover from Rouse to entanglement dynamics. A refined evaluationis presented, which avoids application of frequency–temperaturesuperposition as well as Fourier transformation. Instead, the power-lawexponent ε in the entanglement regime is directly determinedfrom the susceptibility representation χNMR″(ω) = ω/T1(ω) ∝ ωεby a derivative method. Correspondingly, a power-law t–εcharacterizes the decay in the time domain,i.e., the dipolar correlation function. For the total 1H relaxation, comprising intra- and intermolecular relaxation, ahigh-Mexponent εtotal= 0.31 ±0.03 is found. An isotope dilution experiment, which yields the intramolecularrelaxation reflecting solely segmental reorientation, provides anexponent εintra= 0.44 ± 0.03. It agrees with that of FC 2H NMR (εQ= 0.42 ± 0.03) probingonly segmental reorientation. The fact that εintra> εtotaldemonstrates the relevance of intermolecularrelaxation in the entanglement regime (but not in the Rouse regime),and εintrais significantly higher than predictedby the tube-reptation (TR) model (εTR= 0.25) and, the latter being supported also by recent simulations. The ratio of inter- to intramolecularrelaxation grows with decreasing frequency, again in contradictionto the TR model and results from double quantum 1H NMR.We conclude that no clear evidence of a tube is found on the microscopiclevel and the so-called return-to-origin hypothesis is not confirmed.Studying the influence of chain end dynamics by FC 1H NMRwe compare differently chain end deuterated PB. For the dynamics ofthe central part of the polymer the exponent drops from εintra= 0.66 ± 0.03 down to εcent= 0.41 ± 0.03 for M= 29k which is very close to the high-Mvalue εintra. Thus, the protracted transition toentanglement dynamics reported before is not found when the polymercenter is probed; instead full entanglement dynamics appears to setin directly with M> Me. [ABSTRACT FROM AUTHOR]

Knowledge of the macroscopic residual stresses in components of complex high performance alloys is crucial when it comes to considering the safety and manufacturing aspects of components. Diffraction experiments are one of the key methods for studying residual stresses. However a component of the residual strain determined by diffraction experiments, known as microstrain or intergranular residual strain, occurs over the length scale of the grains and thus plays only a minor role for the life time of such components. For the reliable determination of macroscopic strains (with the minimum influence of these intergranular residual strains), the ISO standard recommends the use of particular Bragg reflections. Here we compare the build-up of intergranular strain of two different precipitation hardened IN 718 (INCONEL 718) samples, with identical chemical composition. Since intergranular strains are also affected by temperature, results from room temperature measurement are compared to results at T =550 °C. It turned out that microstructural parameters, such as grain size or type of precipitates, have a larger effect on the intergranular strain evolution than the influence of temperature at the measurement temperature of T =550 °C. The results also show that the choice of Bragg reflections for the diffractometric residual stress analysis is dependent not only on its chemical composition, but also on the microstructure of the sample. In addition diffraction elastic constants (DECs) for all measured Bragg reflections are given. [ABSTRACT FROM AUTHOR]

Two low-background setups for material screening based on HPGe detectors were built in the Garching Underground Laboratory with an overburden of ~10 m.w.e. They include several layers of passive shielding as well as an active muon veto. The first setup (GEM) comprises a 150% efficiency HPGe detector which can optionally be surrounded by a NaI(Tl) scintillation detector that serves as anti-Compton veto. The second setup (LoAx) consists of two smaller HPGe detectors which are arranged face-to-face to cover a larger solid angle around the sample and to allow coincidence measurements. For a 5.6 kg piece of copper after 11 days of measurement we have reached a sensitivity for 226 Ra and 228 Ra/ 228 Th of ~5 mBq kg −1 with the GEM setup. In the LoAx setup we have achieved limits of less than 100 mBq kg −1 for 234 Th and 210 Pb with a 156 g sample of PPO wavelength shifter after 18 days of measurement. [ABSTRACT FROM AUTHOR]

The study evaluates the SPIKES protocol in an actual-theoretical comparison using the Marburg Breaking Bad News Scale (MABBAN). The procedure, the quality of and patient's preferences for bad news delivery, as well as emotional consequences are investigated in 350 German cancer patients. Only 46.2% of the asked patients are completely satisfied how bad news had been broken to them, while the overall quality is significantly related to the emotional state after receiving bad news (r = -.261, p < .001). Patients preferences differ highly significantly from the way bad news were delivered, and the resulting rang list of patients preferences indicates that the SPIKES protocol do not fully meet the priorities of German cancer patients. Therefore some adjunctions to the SPIKES-protocol should be considered, including a frequently reassurance of listeners understanding, the perpetual possibility to ask question, respect for prearrangement needs and the conception of bad news delivery in a two-step procedure.Background Evaluation of the SPIKES protocol, a recommended guideline for breaking bad news, is sparse, and information about patients' preferences for bad-news delivery in Germany is lacking. Being the first actual–theoretical comparison of a ‘breaking bad news’ guideline, the present study evaluates the recommended steps of the SPIKES protocol. Moreover, emotional consequences and quality of bad-news delivery are investigated. Patients and methods A total of 350 cancer patients answered the MABBAN (Marburg Breaking Bad News Scale), a questionnaire representing the six SPIKES subscales, asking for the procedure, perception and satisfaction of the first cancer disclosure and patient’s assign to these items. Results Only 46.2% of the asked cancer patients are completely satisfied with how bad news had been broken to them. The overall quality is significantly related to the emotional state after receiving bad news (r = −0.261, P < 0.001). Patients’ preferences differ highly significantly from the way bad news were delivered, and the resulting rang list of patients’ preferences indicates that the SPIKES protocol do not fully meet the priorities of cancer patients in Germany. Conclusions It could be postulated that the low satisfaction of patients observed in this study reflects the highly significant difference between patients’ preferences and bad-news delivery. Therefore, some adjunctions to the SPIKES protocol should be considered, including a frequent reassurance of listeners’ understanding, the perpetual possibility to ask question, respect for prearrangement needs and the conception of bad-news delivery in a two-step procedure. [ABSTRACT FROM PUBLISHER]

Abstract: The crystal field excitations of the rare earth intermetallic compound YbMn2Si2 have been measured by inelastic neutron scattering over the temperature range 2.5–50K. The YbMn2Si2 spectra exhibit three low energy excitations (~3–7meV) in the antiferromagnetic AFil region above the magnetic phase transition at T N2 = 30(5)K. The crystal field parameters have been determined for YbMn2Si2 in the antiferromagnetic AFil region. A further two inelastic excitations (~9meV, 17meV) are observed below T N2=30(5)K, the temperature at which the high temperature antiferromagnetic structure is reported to exhibit doubling of the magnetic cell. Energy level diagrams have been determined for Yb3+ ions in the different sites above (single site) and below the magnetic transition temperature (two sites). The excitation energies for both sites are shown to be temperature independent with the temperature dependences of the transition intensities for the two sites described well by a simple Boltzmann model. The spectra below T N2 cannot be described fully in terms of molecular field models based on either a single Yb3+ site or two Yb3+ sites. This indicates that the magnetic behaviour of YbMn2Si2 is more complicated than previously considered. The inability to account fully for excitations below the magnetic phase transition may be due to an, as yet, unresolved structural transition associated with the magnetic transition. [Copyright &y& Elsevier]

The scintillation light of liquid argon has been recorded wavelength and time resolved with very good statistics in a wavelength interval ranging from 118 nm through 970 nm. Three different ion beams, protons, sulfur ions and gold ions, were used to excite liquid argon. Only minor differences were observed in the wavelength-spectra obtained with the different incident particles. Light emission in the wavelength range of the third excimer continuum was found to be strongly suppressed in the liquid phase. In time-resolved measurements, the time structure of the scintillation light can be directly attributed to wavelength in our studies, as no wavelength shifter has been used. These measurements confirm that the singlet-to-triplet intensity ratio in the second excimer continuum range is a useful parameter for particle discrimination, which can also be employed in wavelength-integrated measurements as long as the sensitivity of the detector system does not rise steeply for wavelengths longer than 190 nm. Using our values for the singlet-to-triplet ratio down to low energies deposited a discrimination threshold between incident protons and sulfur ions as low as ∼2.5 keV seems possible, which represents the principle limit for the discrimination of these two species in liquid argon. [ABSTRACT FROM AUTHOR]

We consider a system with symmetries whose configuration space is a compact Lie group, acted upon by inner automorphisms. The classical reduced phase space of this system decomposes into connected components of orbit type subsets. To investigate hypothetical quantum effects of this decomposition one has to construct the associated costratification of the Hilbert space of the quantum system in the sense of Huebschmann. In the present paper, instead of the decomposition by orbit types, we consider the related decomposition by reflection types (conjugacy classes of reflection subgroups). These two decompositions turn out to coincide, e.g., for the classical groups SU(n) and Sp(n). We derive defining relations for reflection type subsets in terms of irreducible characters and discuss how to obtain from that the corresponding costratification of the Hilbert space of the system. To illustrate the method, we give explicit results for some low rank classical groups. [ABSTRACT FROM AUTHOR]

The article focuses on a diffractometer STRESS-SPEC at the German neutron source Heinz Maier-Leibnitz (FRM II) for use in areas of engineering and applied materials science. STRESS-SPEC has been used for several experiments such as stress measurements in weldments, non-damaging stress determination of surface treated steel specimens and non-damaging analysis of batteries. It also discusses the versatility of an engineering diffractometer in addressing engineering problems.

Abstract: A powder neutron diffraction measurement of Er5Rh4Ge10 is reported. This compound crystallizes in the tetragonal Sc5Co4Si10-type structure (space group P4/mbm) in which the Er atoms occupy three different sites. The neutron diffraction measurements indicate antiferromagnetic order with the Néel temperature T N=5.5K. Below T N an additional phase transition connected with the change of the magnetic structure is observed at 4.3K. At low temperatures the Er moments form a sine-wave modulated structure with the propagation vector k=(¼, ¼, 0) for 1.5K

Currently, there are no accurate and simple methods available to measure this risk of atrophy in patients treated with topical glucocorticosteroids. In the present clinical trial, we validated a new score (Dermaphot score) to assess the atrophogenic potential of glucocorticosteroids. 36 healthy adult volunteers were included in an investigator-initiated, blinded, randomized, intra-individual comparison, vehicle controlled multi-centre study. Subjects were treated in a randomized manner for 3 weeks with pimecrolimus cream 1 %, mometasone furoate (1 mg/g), clobetasol propionate 0.05 % and vehicle. In addition, ultrasound examination for skin thickness was performed. Data demonstrated a direct correlation of the achieved Dermaphot score and the ultrasound thickness measurements. Our study shows that the Dermaphot score can be used as a simple method to evaluate the atrophogenic potential of glucocorticosteroids. Respectively, we showed that the new score is an easy, valid and sensitive new tool for early detecting and quantifying even subclinical glucocorticosteroid-induced skin damage. We demonstrated that the score is able to differentiate the extent of skin atrophy (damage) after 3 weeks of topical glucocorticosteroid application with different levels of skin transparency and levels of telangiectasia. [ABSTRACT FROM AUTHOR]

The transmission of liquid argon has been measured, wavelength resolved, for a wavelength interval from 118 to 250 nm. The wavelength dependent attenuation length is presented for pure argon. It is shown that no universal wavelength independent attenuation length can be assigned to liquid argon for its own fluorescence light due to the interplay between the wavelength dependent emission and absorption. A decreasing transmission is observed below 130 nm in both chemically cleaned and distilled liquid argon and assigned to absorption by the analogue of the first argon excimer continuum. For not perfectly cleaned argon a strong influence of impurities on the transmission is observed. Two strong absorption bands at 126.5 and 141.0 nm with approximately 2 and 4 nm width, respectively, are assigned to traces of xenon in argon. A broad absorption region below 180 nm is found for unpurified argon and tentatively attributed to the presence of water in the argon sample. [ABSTRACT FROM AUTHOR]

The therapeutic efficacy of humanized or chimeric second-generation antitumor antibodies is clearly established, but often limited. In recent years, defined modifications of the glycosylation pattern or the amino-acid sequence of the human immunoglobulin G1 Fc part have resulted in the development of third-generation antibodies with improved capability to recruit Fc receptor-bearing effector cells. The first antibodies of this kind, currently evaluated in early clinical trials, are directed against lymphoma-associated antigens. Fc-engineered antibodies targeting myeloid leukemia are not yet available. We here report on the generation and preclinical characterization of an Fc-optimized antibody directed to the FMS-related tyrosine kinase 3 (FLT3), an antigen expressed on the leukemic blasts of all investigated patients with acute myeloid leukemia (AML). This antibody, termed 4G8SDIEM, mediated markedly enhanced cellular cytotoxicity against FLT3-expressing cell lines as well as blasts of AML patients. FLT3 expression levels on AML cells varied between 300 and 4600 molecules/cell and, in most cases, were substantially higher than those detected on normal hematopoietic precursor cells and dendritic cells (approximately 300 molecules/cell). Antibody-mediated cytotoxicity against these normal cells was not detectable. 4G8SDIEM has been produced in pharmaceutical quality in a university-owned production unit and is currently used for the treatment of leukemia patients. [ABSTRACT FROM AUTHOR]

Poly(propylene glycol), poly(isoprene), and poly(dimethlylsiloxane) (PDMS) of different molecular masses Mareinvestigated by field-cycling 1H NMR relaxometry to monitorthe crossover from segmental dynamics, to Rouse and entanglement dynamics.The spin–lattice relaxation dispersions T1(ω) obtained at different temperatures (160 K –400 K) are converted to the susceptibility representation χ″DD(ω) = ω/T1(ω). Applying frequency–temperature superposition,the data are merged to provide master curves χ″DD(ωτs) withτs= τs(T) being the segmental correlation times.Combining them with those from dielectric spectroscopy about 12 decadesin time are covered. A similar Mdependence of χ″DD(ωτs) is observed for all polymers (t≫ τs) and comparison with dielectric normal modespectra is carried out. In the case of PDMS showing particularitiesat t≈ τswe attempt to separate intra- and intermolecular relaxation contributions.Transformation into time domain yields the dipolar correlation function CDD(t/τs) which covers up to six decades in amplitudeand eight decades in time. Whereas glassy dynamics is observed atshortest times, the correlation function closely follows CDD(t) ∝ t–1at intermediate times as predictedby the Rouse theory. For longer times and high Mentanglementsets in yielding CDD(t) ∝ t–εwith ε (<1) being M-dependent. As forthe previously studied poly(butadiene), a highly protracted transitionto full reptation is observed. [ABSTRACT FROM AUTHOR]

Abstract: The palaeogeographic position of South China in relation to India in the Neoproterozoic is controversial. Resolution of this controversy constrains the reconstruction of Rodinia during its breakup and contributes to our understanding of Snowball Earth. This work compares the Neoproterozoic histories of the Lesser Himalaya in northern India and the Yangtze block in southern China. We present U–Pb LA-ICP-MS ages of detrital zircon grains from six Indian and three Chinese siliciclastic sedimentary rocks, such as sandstones or diamictites/tillites. In total, 1148 grains were analysed from which 833 measurements gave ages with a degree of concordance between 90 and 110%. The correlation of the Indian and the Chinese sections is possible using the tillites of both areas purportedly deposited during the Snowball Earth time interval: the Blaini tillite from India and the Nantuo tillite from China. The U–Pb ages confirm the Marinoan age of the Chinese Liantuo tillite. Although the youngest zircon age for the Indian Blaini tillite is about 678Ma, the Marinoan age is indicated by the presence of a typical Marinoan white to bright yellowish overlying cap carbonate. In addition to the tillites, representative detrital zircon ages from over- and underlying clastic rocks were determined. The Chinese samples are dominated by zircons with Neoproterozoic ages with a main peak between ca. 750Ma and ca. 950Ma and are characterised by the absence of Archaean ages. The Indian samples contain abundant Neoproterozoic zircon grains, but also contain Mesoproterozoic to Archaean zircons. For all samples, a local source area that provided the Neoproterozoic zircons is likely. A synchronous Neoproterozoic magmatic event in both cratons probably reflects the breakup of the supercontinent Rodinia and therefore the same tectono-magmatic event. Our results indicate a similar history for India and South China which both underwent at least one synchronous episode of crustal growth during the Neoproterozoic. In addition, our data set shows that both passive margin clastic sequences had the same source area for all zircons older than Neoproterozoic. Therefore we infer that India and South China were close to each other and along the same passive margin during the breakup of Rodinia in the Late Neoproterozoic. [Copyright &y& Elsevier]

Background: Attitudes of medical students form the basis for medical actions. Because of the specific characteristics of psychiatric patients, positive attitudes of medical students towards psychiatry should be a higher goal in medical education. Aim: We hypothesize that medical students in different educational programs develop different attitudes towards psychiatry. Methods: In a cross-sectional study, students enrolled in different educational programs completed the 'attitudes towards psychiatry' questionnaire (ATP-30). Data concerning experiences in psychiatry, personality traits and socio-demographic variables including gender were also analyzed. Results: The response rate of students in the PBL-curriculum (n = 61) was >90%, in the traditional curriculum (n = 280) >75%. Attitudes towards psychiatry of male students in the Problem-Based Learning program were equal to the female students' attitudes in both programs. Female students' attitudes in the traditional curriculum reached comparably good results while male students' displayed the worst attitudes. The personality factors 'openness to experience' and 'agreeableness' correlated significantly with positive attitudes towards psychiatry. PBL-students showed significantly more 'openness to experience'. Conclusion: Educational programs might play a role for the development of attitudes towards psychiatry, especially in male students. Factors influencing enrollment into special educational programs should also have been taken into account. An independent study with a larger number of participants will be required to support these findings. [ABSTRACT FROM AUTHOR]

Abstract: Non-destructive analysis of phase specific residual stresses and textures is only possible by diffraction methods. The new neutron diffractometer STRESS-SPEC was installed at FRM-II in Munich, Germany, for this purpose. It is designed to be equally applied to texture and residual stress analyses by virtue of its flexible configuration. The results of measurements on a single bead on plate weld within the framework of the European Network on Neutron Techniques Standardisation for Structural Integrity (NET) are presented here, in order to demonstrate the reliability and accuracy of the instrument by comparing previous results from other neutron diffraction facilities by using a Bayesian statistical approach. [Copyright &y& Elsevier]

Contents Spermatogonial stem cells (SSCs) reside within specialized microenvironments called ‘niches’, which are essential for their maintenance and self-renewal. In the mammalian testis, the main components of the niche include the Sertoli cell, the growth factors that this nursing cell produces, the basement membrane, and stimuli from the vascular network between the seminiferous tubules. This review focuses on signalling pathways maintaining SSCs self-renewal and differentiation and describes potential mechanisms of regulation of the spermatogonial stem cell niche. [ABSTRACT FROM AUTHOR]

Aims: Human epidermal growth factor receptor 2 (HER2) overexpression/amplification is implicated in the development of various solid tumour types. Validated methods and scoring systems for evaluating HER2 status exist in breast cancer, but not in gastric cancer. The aim was to establish a HER2 scoring system for gastric cancer to identify suitable patients for enrolment in a trial of trastuzumab (Herceptin®) in advanced metastatic gastric cancer. Methods and results: Formalin-fixed paraffin-embedded gastric cancer samples were tested for HER2 status using the fluorescence in situ hybridization (FISH) pharmDx™ kit (Dako Denmark A/S). Immunohistochemistry (IHC) was performed using the HercepTest™ (Dako). Concordance between FISH and IHC was 93.5% in 168 evaluable samples. Eleven samples were scored as FISH+ but IHC− or equivocal. Conclusions: IHC/FISH discrepancies were attributed to basolateral membranous immunoreactivity of glandular cells resulting in incomplete membranous reactivity and/or a higher rate of tumour heterogeneity in gastric cancer compared with breast cancer. With modifications to the IHC scoring system, the HercepTest™ is considered valid for the identification of HER2+ gastric tumours for this clinical trial. Correlation of HER2 scores with clinical outcomes will be needed to determine which patients might benefit from trastuzumab therapy. [ABSTRACT FROM AUTHOR]

This paper describes the applicability of laser-induced incandescence (LII) as a measurement technique for primary soot particle sizes at elevated pressure. A high-pressure burner was constructed that provides stable, laminar, sooting, premixed ethylene/air flames at 1–10 bar. An LII model was set up that includes different heat-conduction sub-models and used an accommodation coefficient of 0.25 for all pressures studied. Based on this model experimental time-resolved LII signals recorded at different positions in the flame were evaluated with respect to the mean particle diameter of a log-normal particle-size distribution. The resulting primary particle sizes were compared to results from TEM images of soot samples that were collected thermophoretically from the high-pressure flame. The LII results are in good agreement with the mean primary particle sizes of a log-normal particle-size distribution obtained from the TEM-data for all pressures, if the LII signals are evaluated with the heat-conduction model of Fuchs combined with an aggregate sub-model that describes the reduced heat conduction of aggregated primary soot particles. The model, called LIISim, is available online via a web interface. [ABSTRACT FROM AUTHOR]

Paddlefish use their peculiar rostrum to detect minute electric fields from their main prey, small water fleas. Electroreceptors over the rostrum and head sense these fields and send the information into a single hindbrain area, the dorsal octavolateral nucleus (DON). From there, information is sent to various midbrain structures, including the tectum. The response properties of primary afferent fibers and DON units has been well investigated, but nothing is known about electrosensory units in the midbrain. Here we recorded the responses of single units in the midbrain tectum and DON to uniform electric fields. Tectal units exhibited little spontaneous activity and responded to sine waves with a few, well phase-locked spikes. Phase locking was still significant at amplitudes one order of magnitude lower than in the DON. If stimulated with sinusoidal electric fields of different frequencies, phase locking in DON units decreased proportionally with frequency whereas the response of tectal units depended little on frequency. This is in agreement with behavioral studies showing that relevant frequencies range from DC to ca 20 Hz. [ABSTRACT FROM AUTHOR]

Aims: To investigate the correlation between centrally assessed human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH) results and response to treatment of patients with metastatic breast cancer enrolled in a first-line, phase II, open-label, 3-weekly trastuzumab (Herceptin) monotherapy trial (W01622). Methods: Samples from participants in the W016229 trial were collected and turnout HER2 status determined by IHC and FISH. HER2 test results were interpreted according to manufacturers' test kit protocols. Responders were defined as patients showing either partial or complete responses. Results: Response data were available for 103/105 patients; centrally confirmed HER2 status was available for 95 patients. Intra-laboratory concordance for central IHC and FISH results was 93%. Complete responses were seen in two patients; their samples were IHC 3+ and FISH positive. Partial responses were seen in 17 patients; all were IHC 3+ and 14 were FISH positive. IHC and FISH showed 100% and 84.2% sensitivity, respectively, in determining response to trastuzumab. Polysomy was observed in 27% of patients; six responded to trastuzumab treatment. All six responders showed HER2 overexpression (IHC 3+) and HER2 gene amplification; two were FISH negative due to chromosome 17 polysomy. Conclusions: HER2 determination by IHC and FISH correlates with clinical response data in the W016229 trial with high concordance of IHC and FISH results. Polysomy is the major cause of response in FISH-negative cases; polysomic cases should be retested by strictly standardised IHC. [ABSTRACT FROM AUTHOR]

Abstract: Carbon fibre ceramic matrix composite materials, C/SiC, are excellent candidates as lightweight structural materials for high performance hot structures such as in aerospace applications. Satellite nozzles are manufactured from C/SiC, using, for instance, the Liquid Polymer Infiltration (LPI) process. In this article the applicability of different non-destructive analysis methods for the characterisation of C/SiC components will be discussed. By using synchrotron and neutron tomography it is possible to characterise the C/SiC material in each desired location or orientation. Synchrotron radiation using tomography on small samples with a resolution of 1.4 μm, i.e. the fibre scale, was used to characterise three dimensionally fibre orientation and integrity, matrix homogeneity and dimensions and distributions of micro pores. Neutron radiation tomography with a resolution of about 300 μm was used to analyse the over-all C/SiC satellite nozzle component with respect to the fibre content. The special solder connection of a C/SiC satellite nozzle to a metallic ring was also successfully analysed by neutron tomography. In addition, the residual stress state of a temperature tested satellite nozzle was analysed non-destructively in depth by neutron diffraction. The results revealed almost zero stress for the principal directions, radial, axial and tangential, which can be considered to be the principal directions. [Copyright &y& Elsevier]