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The influence of the atom source operating parameters on the structural and optical properties of In x Ga 1 − x N/GaN nanowires (NWs) grown by plasma-assisted molecular beam epitaxy is investigated. Electron microscopy and photoluminescence spectroscopy reveal a change of the NW tip morphology and an enhancement of the local indium incorporation with increasing nitrogen flux. Tuning the density ratio of atomic-to-excited molecular nitrogen to lower values minimizes the point defect density, which results in a decrease of the non-radiative recombination rate as demonstrated by a combination of continuous wave and time-resolved photoluminescence spectroscopy. [ABSTRACT FROM AUTHOR]

ABSTRACT In ultrasonic fatigue tests, the VHCF properties can be determined in a reasonable time. Nevertheless, the high frequency can affect the fatigue behavior for some materials. This study investigated the fatigue capability of 34CrNiMo6 and 42CrMo4 steels, both of which find widespread applications in several mechanical components. These steels were carried out for conventional and ultrasonic fatigue tests under fully reversed testing conditions. A microplasticity strain amplitude was calculated, indicating an order of magnitude decreases around 10–100, when compared with the experimental results from low‐frequency tests. Cyclic strain rates were estimated for each steel and correlated with the number of cycles to failure. A conversion constant was obtained by fitting a curve to convert the high frequency results into theoretical results at low frequency. The experimental and predicted results were evaluated. The results proved the relevance of the strain rate in frequency effect. The converted results showed strong agreement with the experimental results in low‐frequency tests for the steels being studied. [ABSTRACT FROM AUTHOR]

Fatigue behaviour of materials is traditionally performed on probes that ensure that stresses (or strains) are very uniform. This is a situation seldom encountered in most adhesively bonded joints, where stresses usually peak at the end of the overlaps. This paper presents a relatively simple model to predict the fatigue behaviour of glued-in rods (GiR) involving hardwood in previously investigated in an extensive experimental campaign. The model is based on strength and stiffness degradation of the components of the GiR, which were experimentally estimated in small scale tests. Based thereupon, Finite Element Analysis (FEA) was used to estimate the effect of material degradation on the residual strength of the GiR, which was then interpreted as S-N-curves. The influence of several parameters, e.g. strength and stiffness degradation rates and the magnitude of the residual strength threshold were numerically investigated. The result showed that it is possible, using a practitioner adapted numerical model, to predict the fatigue behaviour of GiR, based upon comparatively simple fatigue characterisation on their components. [ABSTRACT FROM AUTHOR]

Aim Blocking of lysophosphatidic acid ( LPA) receptor ( LPAR) 1 may be a novel therapeutic option for bronchopulmonary dysplasia ( BPD) by preventing the LPAR1-mediated adverse effects of its ligand ( LPA), consisting of lung inflammation, pulmonary arterial hypertension ( PAH) and fibrosis. Methods In Wistar rats with experimental BPD, induced by continuous exposure to 100% oxygen for 10 days, we determined the beneficial effects of LPAR1 deficiency in neonatal rats with a missense mutation in cytoplasmic helix 8 of LPAR1 and of LPAR1 and -3 blocking with Ki16425. Parameters investigated included survival, lung and heart histopathology, fibrin and collagen deposition, vascular leakage and differential m RNA expression in the lungs of key genes involved in LPA signalling and BPD pathogenesis. Results LPAR1-mutant rats were protected against experimental BPD and mortality with reduced alveolar septal thickness, lung inflammation (reduced influx of macrophages and neutrophils, and CINC1 expression) and collagen III deposition. However, LPAR1-mutant rats were not protected against alveolar enlargement, increased medial wall thickness of small arterioles, fibrin deposition and vascular alveolar leakage. Treatment of experimental BPD with Ki16425 confirmed the data observed in LPAR1-mutant rats, but did not reduce the pulmonary influx of neutrophils, CINC1 expression and mortality in rats with experimental BPD. In addition, Ki16425 treatment protected against PAH and right ventricular hypertrophy. Conclusion LPAR1 deficiency attenuates pulmonary injury by reducing pulmonary inflammation and fibrosis, thereby reducing mortality, but does not affect alveolar and vascular development and, unlike Ki16425 treatment, does not prevent PAH in neonatal rats with experimental BPD. [ABSTRACT FROM AUTHOR]

Multilayer structures A–B–A⋅⋅⋅ consisting of alternating layers of a metal A and a semiconductor B can show large anisotropy in their transport properties. In tilted multilayer structures, where layer planes and sample surface include a nonzero tilt angle, nonvanishing off-diagonal elements in the sample’s transport tensors lead to transverse Seebeck and Peltier effects. Achievable temperature differences and figures of merit for transverse Peltier cooling are discussed and compared with experiments, coefficients of performance for transverse power generation are calculated. [ABSTRACT FROM AUTHOR]

Objective: To investigate in a randomised controlled trial the effect of basic elements of developmental care (incubator covers and positioning aids) on growth and neurodevelopment in infants born at < 32 weeks. Method: Infants were randomised within 48 h of birth to a developmental care (DC) or standard care (C) group. Outcome measures at 1 and 2 years corrected age were growth, standardised neurological examinations, and mental (MDI) and psychomotor (PDI) development (Dutch version of the Bayley Scales of Infant Development II). Results: 192 infants were recruited (DC = 98; C = 94). Thirteen infants (DC = 7, C = 6) were excluded because they were admitted for <5 days or died within the first 5 days. In total, 179 infants met the inclusion criteria. In-hospital mortality was 12/91 (13.2%) in the DC group and 8/88 (9.1%) in the C group. Assessments were carried out on 147 children (DC = 74, C = 73) at 1 year and 142 children (DC = 72, C = 70) at 2 years. No significant difference in growth, neurological outcomes or MDI was found. A positive trend in PDI at 1 year (p = 0.05) did not continue once the children reached 2 years. There was no difference found when neurological and developmental scores were combined. Conclusions: Basic developmental care has no positive effect on neurological and mental development or growth at 1 and 2 years of age in infants born at <32 weeks. A positive effect on psychomotor development at 1 year did not continue at 2 years of age. Trial registration number: ISRCTN84995192. [ABSTRACT FROM AUTHOR]

Abstract: The deformation-induced martensite formation in metastable austenitic steels is investigated under monotonic and cyclic loading at ambient temperature. Mechanical stress–strain, temperature and magnetic measurements were performed to characterize the cyclic deformation behavior of AISI 304, AISI 321 and AISI 348 stainless steels with particular attention to the deformation-induced martensite formation. On the basis of comprehensive experimental data from plastic-strain-controlled fatigue tests a new model was developed to describe and predict the martensite formation. The process of martensite formation can be modeled as function of the cumulative plastic strain and the cumulative strain-energy density. [Copyright &y& Elsevier]

In this paper, mechanical stress–strain-hysteresis, temperature and electrical resistance measurements are performed for the detailed characterization of the fatigue behaviour of quenched and tempered SAE 4140 steel used for many applications in the automotive industry. Stress-controlled load increase and constant amplitude tests (CATs) were carried out at ambient temperature on servo-hydraulic testing systems. The applied measurement methods depend on deformation-induced changes of the microstructure in the bulk material and represent the actual fatigue state. The plastic strain amplitude, the change in temperature and the change in electrical resistance can be equally used for an assessment of baseline fatigue properties in generalized cyclic deformation curves as well as in generalized Morrow and Coffin–Manson curves. On the basis of comprehensive experimental fatigue data, the physically based fatigue life calculation method ‘PHYBAL’ based on the generalized Basquin equation was developed. S–N (Woehler) curves calculated with ‘PHYBAL’ using data from only three fatigue tests agree very well with the conventionally determined ones. [ABSTRACT FROM AUTHOR]

Abstract: In this investigation, stress-controlled fatigue tests with SAE 1050 and SAE 1065 specimens were performed under single step and random loading to study fatigue mechanisms with particular attention to microstructural details. The applied plastic strain amplitude, temperature and electrical resistance measurements depend on deformation-induced changes of the microstructure and represent the actual fatigue state of the investigated steels. A new test procedure combines any kind of load spectra with periodically inserted single step sequences to measure the plastic strain amplitude, the temperature and the electrical resistance. The average values of the measuring sequences are plotted as function of the number of cycles in cyclic ‘deformation’ curves and represent the summation of microstructural changes caused by random loading. Electrical resistance measurements allow to detect the proceeding fatigue damage even in the load-free state. On the basis of comprehensive experimental fatigue data the physically based lifetime calculation method “PHYBAL” using generalized Morrow, Coffin–Manson and Basquin equations was developed for single step and random loading. S–N (Woehler) curves calculated with “PHYBAL” agree very well with experimentally determined lifetimes. [Copyright &y& Elsevier]

Abstract: Stress-controlled fatigue tests with constant and variable amplitudes were performed with quenched and tempered specimens of the steel SAE 4140 (42CrMoS4) and specimens of the railway wheel steel R7 (SAE 1050) specified in standard 812-3V of the International Railway Union UIC on servohydraulic testing systems. In addition to mechanical stress–strain hysteresis measurements, the changes of temperature and electrical resistance were regarded. All measured values depend on microstructural changes due to plastic deformation processes, and therefore, show a clear interaction with the actual fatigue state. Consequently, a physically based lifetime prediction (PHYBAL) according to Morrow and Manson/Coffin can be derived. A new testing procedure was applied allowing hysteresis measurements for the characterization and description of the fatigue behavior under random and even service loading. The basic idea is to combine any kind of load spectrum with constant load sequences using an amplitude below the endurance limit. This offers the possibility to apply lifetime prediction methods on the basis of cyclic deformation data for random or service loading equivalent to single step tests. Scanning and transmission electron microscopy allow to interpret the measured physical data on the basis of microstructural details. [Copyright &y& Elsevier]

Abstract: In the present work, industrial-scale DC-pulsed plasma nitriding for 20h at 673K was used to improve the wear resistance of an AISI 410 martensitic stainless steel. The tribological behaviour was studied and compared to the behaviour of the same steel in as-received condition. Pin-on-disc dry tests, using an alumina ball as counter-body, were carried out to determine the evolution of the friction coefficient. The wear resistance was investigated using an Amsler-disc-machine, employing a dry combined contact of rolling–sliding with three different applied loads. The wear mechanisms involved during rolling–sliding of unnitrided and plasma nitrided steels were investigated by microscopic observation of the surfaces, the corresponding cross-sections and the produced wear debris. The combination of different wear mechanisms taking place in the wear process of unnitrided and nitrided materials were discussed and analyzed. In contrast to the unnitrided steel, DC-pulsed plasma nitrided samples presented an improvement in the friction coefficient and the wear rate. [Copyright &y& Elsevier]

Surfactant protein B (SP-B) is essential for normal lung surfactant function. Theoretical models predict that the disulfide cross-linked, N- and C-terminal domains of SP-B fold as charged amphipathic helices, and suggest that these adjacent helices participate in critical surfactant activities. This hypothesis is tested using a disulfide-linked construct (Mini-B) based on the primary sequences of the N- and C-terminal domains. Consistent with theoretical predictions of the full-length protein, both isotope-enhanced Fourier transform infrared (FTIR) spectroscopy and molecular modeling confirm the presence of charged amphipathic α-helices in Mini-B. Similar to that observed with native SP-B, Mini-B in model surfactant lipid mixtures exhibits marked in vitro activity, with spread films showing near-zero minimum surface tensions during cycling using captive bubble surfactometry. In vivo, Mini-B shows oxygenation and dynamic compliance that compare favorably with that of full-length SP-B. Mini-B variants (i.e. reduced disulfides or cationic residues replaced by uncharged residues) or Mini-B fragments (i.e. unlinked N- and C-terminal domains) produced greatly attenuated in vivo and in vitro surfactant properties. Hence, the combination of structure and charge for the amphipathic α-helical N- and C-terminal domains are key to SP-B function. [ABSTRACT FROM AUTHOR]

The current investigations concentrate on the relation between the loading and environmental conditions, the local microstructure and the fatigue behavior of highly stressed railway wheel and tire steels. Experiments under stress control and total strain control were performed at ambient temperature with servohydraulic testing systems. Superimposed mean loadings allow an evaluation of cyclic creep and mean stress relaxation effects. Strain, temperature and electrical measuring techniques were used to characterize the cyclic deformation behavior of specimens from different depth positions of the cross-sections of UIC-specified wheel components (UIC: International Railway Union). The measured values show a strong interrelation. The microstructural characterization of the different material conditions was done by light and scanning electron microscopy together with digital image processing. [Copyright &y& Elsevier]

In vitro, mutation induction experiments will become economically relevant only if the genetic if the genetic variation can be highly increased by this procedure. For that purpose the utilization of as high X-ray doses as possible are considered an important prerequisite. It was the objective to investigate the effect of split versus acute X-ray doses on in vitro derived micro-shoots of Gerbera jamesonii used as reference system for plant species that can be propagated in vitro by axillary shoots. Splitting of doses between 19 Gy and 50 Gy into 2 or 3 fractions separated by periods of 4 h each for recovery led to considerably rising shoot production. The recovery from damage, represented by accumulating the number of shoots developed during 16 weeks at 4 subsequent dates of cutoff post-treatment, by propagation profiles, and by calculation of the 'factory of recovery', resulted in the application of very high X-ray doses only usable by means of multiple dose fraction procedures. [ABSTRACT FROM AUTHOR]

The transverse Seebeck effect in tilted metal-semiconductor multilayer structures has been exploited for electric power generation. In tilted Pb-BiTe multilayer samples, coefficients of performance for transverse thermoelectric power generation have been determined, in dependence of temperature difference between hot and cold sample surfaces. The results can be described well by modeling calculations of transverse thermoelectric power generation. [ABSTRACT FROM AUTHOR]

Abstract: It is one of the most important tasks of the forensic pathologist to explain the forensically relevant medical findings to medical non-professionals. However, it is often difficult to comment on the nature and potential consequences of organ injuries in a comprehensive way to individuals with limited knowledge of anatomy and physiology. This rare case of survived pancreatic transaction after kicks to the abdomen illustrates how the application of dedicated software programs for three-dimensional reconstruction can overcome these difficulties, allowing for clear and concise visualization of complex findings. [Copyright &y& Elsevier]

• Advanced in-situ torsional fatigue testing discloses the early occurrence of short cracks. • Short cracks form a continuously growing network leading to coalescence of cracks. • The crack length distribution and the crack densities are discussed in detail. • Complementary, load increase tests disclose the fatigue damage based on material reactions. • Validation of in-situ results by constant amplitude testing in terms of the S-N curve. This study investigates the fatigue behaviour and damage mechanisms of the martensitic spring steel SAE 9254, with emphasis on short crack propagation. Shear stress-controlled torsional fatigue tests are performed at stress ratio R = -1 and test frequency f = 79 Hz using structure-sensitive measurement techniques to detect the relevant damage mechanisms. An in-situ torsional fatigue testing device is applied for shear-controlled fatigue tests at two amplitudes of the torsion angle using R = –1 and f = 5 Hz, and the microstructural-dependent short crack propagation path is documented by means of confocal laser microscopy and electron backscattering analysis. It is found that the early development of fatigue damage is characterised by the formation of slip bands, which serve as crack initiation sites. In this process, crack initiation occurs preferentially at or near prior austenite grain boundaries. Furthermore, prior austenite grain boundaries were identified as obstacles for the propagation of short cracks, because of the change of the crystallographic orientation leading to an oscillating propagation rate of short cracks. The short crack density ρ CD , which is an important parameter for fatigue damage, is rapidly growing with increasing shear stress amplitude Δτ T /2 and reveals a stress type specific behaviour. [ABSTRACT FROM AUTHOR]

Background and Objectives Pregnant women with Idiopathic thrombocytopenic purpura ( ITP) can deliver neonates with severe thrombocytopenia. Clear evidence declaring the pathophysiological cause of this neonatal thrombocytopenia is lacking, as antiplatelet antibodies are not always detectable in maternal serum. Severe neonatal thrombocytopenia below 50 × 109/l is reported in 8-13% of the neonates from mothers with ITP and intracranial haemorrhage ( ICH) in 0-2·9%. Evidence about the optimal postnatal treatment is scarce. Our objective was to evaluate the outcome and management in neonates with passive ITP. Materials and Methods All neonates from mothers with ITP born between 1980 and 2011 were included. Platelet counts during the first 10 days, presence of ICH and postnatal treatment were recorded. Maternal characteristics were analysed as possible risk factors for severe neonatal thrombocytopenia. Results Sixty-seven neonates were included. Severe thrombocytopenia (<50 × 109/l) occurred in 20/67 (29·9%) neonates. In three neonates, platelet count rose spontaneously, 18 neonates were treated (one with persistent moderate thrombocytopenia) with the following: platelet transfusions (3), prednisone (2), intravenous immunoglobulin ( IVIG) (1), platelet transfusions and IVIG (11), platelet transfusion and prednisone (1). Recurrence of low platelet counts after transfusions was commonly seen. Risk factors for severe neonatal thrombocytopenia were a previous sibling with severe thrombocytopenia and low maternal platelet nadir during pregnancy. Conclusion In this cohort, severe neonatal thrombocytopenia occurs more frequently than previously reported. To maintain a platelet count above 50 × 109/l, often multiple transfusions and IVIG are required. Multiple transfusions may be avoided by starting IVIG, when platelet count falls below 50 × 109/l after the first platelet transfusion. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 35-year-old woman at 23 weeks' gestation which likely has congenital cystic adenomatoid malformation (CCAM). Ultrasound examination shows a lesion in the left side of the thorax and was assumed to be a bronchopulmonary sequestration (BPS). With the presence of fetal hydrops and a large hydrothorax, one ultrasound-guided thin needle insertion was performed successfully and a neonate was delivered uneventfully at term.

This research addresses the problem of accurately quantifying the strain rate effect of carbon fibre-reinforced plastics by proposing a method with a simple specimen manufacturing and experiment execution based on four-point bending tests. By easing the strain rate-dependent characterization of carbon fibre-reinforced plastics, less conservative designs can be achieved. The method proposed uses Euler–Bernoulli and Timoshenko's beam theories to obtain the longitudinal compressive and tensile modulus, compressive strength, shear modulus, and shear yielding point. Transverse properties could not be obtained due to limitations of the fixture employed. A strain-dependent material characterization was done using the proposed method and compared to the characterization of the same material using traditional uniaxial tests. Most of the material properties obtained with different methods correlated within approximately 10%. More work needs to be done to determine how this discrepancy affects simulation results. [ABSTRACT FROM AUTHOR]

Glued-in Rods (GiR) are among the high-performance joining technologies used in timber engineering. Engineering design procedures for GiR almost exclusively regulate softwood and softwood engineered wood products (EWP) under quasi-static loads. Since the use of hardwood is expected to significantly increase due to climate change, and potentially establish itself as predominant in Europe's forests, GiR in combination with hardwood and corresponding EWP need to be investigated. Timber constructions subjected to cyclic loads are increasingly being used, as for example in timber bridges, high rise buildings, and wind turbine towers. No normative regulation is yet available for fatigue of GiR, which is for most part due to incomplete or completely missing experimental data. This paper is the first of a two part series; it presents fatigue investigations on GiR in combination with hardwood EWP with different types of rods, wood species and adhesives. Further, the embedment length and stress ratio were varried. In total, more than 70 cyclic tests were performed resulting in a high number of SN-curves showing the fatigue characteristics of GiR. The results show that two different damage mechanisms exist: in low cycle fatigue range (LCF), timber and adhesive fracture become dominant, while rod failure is the limiting factor in high cycle fatigue range (HCF). Based upon the documented experimental findings, existing standards for cyclic load on softwood connection technologies were discussed. The compagnion paper will present a design methodology based on a wood damage accumulation, giving a complete picture combined with existing metal fatigue models. [ABSTRACT FROM AUTHOR]

Traditional Extreme Value Statistics (EVS) applied to block maxima sampled anomalies of components produced by Laser-Powder Bed Fusion may produce important inaccuracies in the estimated characteristic defects. In fact, the typical presence of multiple defect types may significantly affect the fitted maxima distributions obtained from different sampling volumes. In this work, we show how the limitations of traditional EVS can be overcome by applying supervised machine learning (ML) algorithms to classify the defects before estimating the maxima distributions for each defect type. The ML-assisted EVS provided maxima distributions unaffected by the different sampling volumes. The obtained maxima distribution lead to robust estimates of exceedance curves and finally, by employing the Shiozawa curve, to robust fatigue strength predictions. • Proposal of a new procedure for Extreme Value Statistics when multiple anomaly types are present. • Machine-learning assisted Extreme Value Statistics provide stable maxima distributions of anomalies. • Stable maxima distributions lead to robust defect-based fatigue strength predictions. [ABSTRACT FROM AUTHOR]

• Inducing a high plastic deformation using flow drilling and cold thread forming. • Quantifying the work hardening according to the thermo-mechanical affected zone. • Decrease in core hole diameter enhance the geometry of the formed thread profiles. • Determining the moment and position of crack initiation and propagation in fatigue. • Possible compromise between the quality of the formed thread and the tool's lifetime. Manufacturing the internal thread in lightweight components using chipless flow drilling and internal thread forming processes can reduce material and time consumption. Furthermore, using these methods imposes a further work-hardening into the subsurface of the formed thread profiles and consequently improves the thread strength. While the required core hole diameter for conventional (cut) tapping depends on the thread dimension, this diameter depends either on the material properties such as ductility for the thread forming process (form tapping). This work investigates the effect of the used process parameters in flow drilling (friction drill speeds and diameter) on the quality of the drilled bores and the formed threads. A total metallographic analysis was performed according to the formed regions by the flow drilling process and was correlated to the measured hardness profile conducted along the bore thickness. The CT scan was chosen to measure the dimension deviation of the manufactured bores and their effects on the formed threads. Correlating the deviation to the quasi-static and dynamic strengths declared that decreasing the tool diameter by 0.1 mm decreased the inner volume of the friction drilled bore, which enhanced the geometry of the formed thread and increased the percentage of the thread engagement and the strengths accordingly. Although the friction drilling with an adaptive speed reduced the oversizing of the created bore in comparison to the flow-drilled bores with a constant speed, measuring the volume of the formed threads into mentioned bores indicated an opposite trend. While the formed M6 threads into the flow drilled bores with constant speed showed a better strength by subjecting to a quasi-static load, manufactured threads with an adaptive speed indicated a higher dynamic strength from the load increase fatigue test. S-N curves declared that the adapted flow drilling speed led to higher dynamic strength of the formed thread subjecting to the fatigue tests in the HCF (High Cycle Fatigue) range. The measured results from NDT monitoring by the ACPD method were correlated to plastic strain up to failure. The in-situ quasi-fatigue test in the CT scan clarified the fatigue fracture according to cyclic softening and hardening, or possible crack initiation and propagation in thread profiles during the fatigue test. [ABSTRACT FROM AUTHOR]

A high alloy CrMnNi TRIP steel has been processed by electron beam melting, a powder-bed based additive manufacturing (AM) technology, to investigate its fatigue properties. The material was characterized by average grain sizes of 32 μm in the as-built and 106 μm in the solution annealed state. Total strain controlled fatigue tests with strain amplitudes in the range of 0.25% ≤ Δε t /2 ≤ 1.2% were performed revealing a similar cyclic deformation behavior and α′-martensite evolution compared to a hot pressed reference material. Moreover, the fatigue lives of the EBM states were surprisingly high in consideration of severe process-induced lack of fusion defects of more than 500 μm revealed by investigations of the fracture surfaces. Thus, the impact of these inhomogeneities was substantially alleviated by the outstanding damage tolerance of the present TRIP steel induced by its high ductility and remarkable hardening capacity. [ABSTRACT FROM AUTHOR]

The usage of fibre-reinforced composites in automotive body structures is still a rarity. The main goal in body structure development is to design lightweight structures as cost-efficient as possible. This research contributes to the approach of maximal material usage by considering the strength increase of a carbon-epoxy laminate with increasing strain rate. The objective was to substantiate the well-known material characteristic’s strain rate dependency from a coupon level to realistic body structure component – experimentally and numerically. Hence, a special compression fixture was developed to obtain all necessary characteristic values of the investigated T700S DT120 prepreg system. The rectangular coupon specimens were loaded with quasi-static to intermediate strain rates ( 2 × 10 - 4 to 70 s - 1 ). A second compression fixture was developed to axial load omega cross-sectional specimens with strain rates from 2 × 10 - 4 to 5 s - 1 . The experimental tests showed a significant increase of + 23 % and + 21 % in compression strength for rectangular coupon specimens and omega cross-sectional components, respectively. Furthermore, the numerical simulation showed the same increase in strength of + 21 % for omega cross-sectional components. This work has proven the necessity of considering the strain rate dependency of a composite material to accurately predict the maximum load capacity of a structure during a dynamic load event like a crash. [ABSTRACT FROM AUTHOR]

Abstract: Materials and brazed joints for automotive exhaust systems have to resist the corrosive nature of aggressive exhaust gases as well as static and cyclic loads. In the present study, the influence of condensate corrosion according to VDA 230–214, with an ageing duration of up to 6 weeks, on the tensile and fatigue properties of stainless steel AISI 304L and brazed AISI 304L/BNi‐2 joints is investigated. In relation to the as‐received condition, the ultimate tensile strength is decreased down to 58 % and a reduction of the fatigue strength at 2⋅106 cycles down to 22 % is determined for brazed specimens, pre‐corroded for 6 weeks. In contrast to the brazed stainless steel joints, the condensate corrosion does not influence the tensile properties of the AISI 304L base material. Stress concentrations at the corrosion‐dependent circumferential grooves at the brazing seam are evaluated by stress intensity factors, which are well appropriate to characterise the fatigue behaviour depending on the corrosion condition. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys are attractive for lightweight construction, but suffer often from poor corrosion resistance. Plasma electrolytic oxidation is a promising surface treatment to overcome these limitations. Recently, introduction of particles to the PEO electrolyte has been explored as new strategy to provide a wider range of compositions and new functionalities for PEO coatings. However, this surface treatment can have negative impact on the fatigue strength. In the present study, the influence of PEO coatings with and without particle addition on the corrosion fatigue behavior of AZ31 Mg alloy is investigated. The corrosion fatigue behavior is investigated in load increase tests and constant amplitude tests in 0.5% NaCl solutions. Results are correlated with the corrosion behavior evaluated in polarization and electrochemical impedance spectroscopy measurements. Corrosion tests show significant improvement of the corrosion resistances of PEO-coated specimens. However, the uncoated material exhibits the highest corrosion fatigue strength, whereas a reduction of 7% for the PEO-coated specimen without particles and 27% for the PEO-coated specimen with particles is found. [ABSTRACT FROM AUTHOR]

Fatigue life assessment for two-phase steel SAE 1045 has been carried out by experimental and simulation techniques. Analytical approach, termed as fatigue lifetime calculation, was employed making use of a load increase testing procedure and constant amplitude tests equipped with measurement techniques - plastic strain amplitude, change in temperature and change in electrical potential difference. The predicted fatigue life has been validated by constant amplitude tests and compared with fatigue life estimation by microstructure-based simulation. Simulation has been carried out over the complete cross section of the specimen. The simulation uses damage accumulation in the gage section of the specimen culminating in the macro-crack propagation, taking into account the inhomogeneous fatigue resistance of the material element. The results show that at the initial intervals of high cycle fatigue range at relatively higher stress amplitudes, the experimental and simulation results are in agreement; whereas in the (high cycle fatigue) region at relatively low stress amplitudes, the simulation results were found more optimistic and the corresponding fatigue scatter is also increased. Each scatter is attributed to the relatively small number of analysed models of the material structure. Scanning electron microscope was used to determine volume fraction of the microstructure for simulation. Fatigue fracture surface analysis shows that crack initiated from internal defect of material and crack propagation is driven by silicon oxide inclusion. [ABSTRACT FROM AUTHOR]

• Mechanical and microstructural characterization of additively manufactured TiAl. • Effect of manufacturing-related defects on the fatigue behavior. • Model-based description and validation of defect-dependent fatigue behavior. • Representation is independent of defect type, size, and test temperature. • Visualization of the influence of theoretical defects with synthetic S-N curves. The additively manufactured titanium aluminide alloy TNM-B1 was characterized microstructurally and mechanically in the as-built and hot isostatically pressed (HIP) condition. Tensile and constant amplitude tests were performed at room temperature and 800 °C. Using fractographic SEM images, the fracture-inducing defect was identified. With the HIP, defect number and size could be reduced, increasing fatigue strength by 43% to 500 MPa. Using the model approaches of Murakami and Shiozawa, the fatigue life was correlated with the local stress intensity factor and could be described as function of the stress amplitude as well as the size and location of fracture-inducing defects. [ABSTRACT FROM AUTHOR]

In order to provide longer LED lifetimes, all LED-related components, including lenses and other optical components, need to be adapted to increasing radiation levels. Pulse width modulation (PWM) is an easy-to-implement method for driving and dimming LEDs and could be a cost-effective way to extend the lifetime of optical components installed in conjunction with the LED. In this study, polycarbonate (PC) samples were artificially aged with high-power blue LEDs using different driving modes in a newly developed test setup. The LEDs were pulse-width modulated in three different modes (50% duty cycle, 25% duty cycle, and continuous wave (CW)), while emitting the same optical power. Optical light microscopy, UV/vis spectroscopy, FTIR spectroscopy and gel permeation chromatography were performed to measure transmittance changes and general aging effects of the samples. The results indicate a substantial correlation of aging with the mode of exposure. It is found that the samples age most severely under CW irradiation, as both the decrease in transmission (at 295 nm wavelength, after 1500 h) and the sample temperature, and thus the degradation, are highest. FTIR spectroscopy showed the expected results for optical aging under LED irradiation, again the changes tended to be more pronounced for the samples irradiated without PWM. Gel permeation chromatography shows a decrease in the weight averaged molar mass, once more with the CW irradiated samples exhibiting the most significant decrease. However, optical light microscopy did not reveal any significant aging effects on the sample surface. Overall, modulation of the LED, and in particular a reduction of the duty cycle, has a positive effect on the durability of optical plastics at similar radiative energy loads. In order to explain the different aging behavior of the samples under the different driving modes, a model of the time-related temperature changes in the material during the heating phase at different duty cycles is proposed. • Resistance assessment of polycarbonate to modulated radiation. • Frequency and pulse width modulation (PWM) of the LED. • Aligned optical power at different pulse widths. • Identification of aging phenomena by optical, chromatographic and pyrometric methods. • Lower duty cycle has a positive effect on durability (e.g. yellowing). [ABSTRACT FROM AUTHOR]

Objectives: We aimed to assess the characteristics of posterior fossa (PF) abnormalities in a cohort of high-risk term neonates, as well as the diagnostic performance of cranial ultrasound (CUS) with additional mastoid fontanelle (MF) views for the detection of these abnormalities, with magnetic resonance imaging (MRI) being the reference standard. Methods: In this retrospective study, 113 term neonates with CUS and subsequent MRI were included. Sensitivity, specificity, and predictive values of routine CUS and CUS with MF views were calculated. Results: Posterior fossa abnormalities were diagnosed on CUS in 46 of 113 infants. MRI confirmed these findings in 43 and showed additional abnormalities in 32 infants. The sensitivity and specificity of anterior fontanelle views for major PF abnormalities as seen on MRI were 16 % and 99 %. Adding MF views increased the sensitivity of US to 82 %. The sensitivity and specificity of MF views for the detection of any (major or minor) PF abnormality were 57 % and 95 %. Especially acute hypoxic-ischemic injury and small subdural and punctate cerebellar haemorrhage remained undetected by CUS. Conclusions: PF abnormalities are frequent in high-risk term infants. MF-CUS enables early diagnosis of major PF abnormalities. We therefore advocate to perform MF-CUS in high-risk term neonates. Key Points: • Posterior fossa abnormalities are a frequent finding in high-risk term infants. • Adding mastoid fontanelle views improves ultrasound detection of clinically relevant abnormalities. • Hypoxic-ischemic injury and small posterior fossa haemorrhages are better detected with MRI. • Cranial ultrasound examination should include mastoid fontanelle views in high-risk term neonates. [ABSTRACT FROM AUTHOR]

The aims of this study were to analyze reproductive outcomes of women and men born very preterm (gestational age <32 weeks) or with a very low birth weight (<1500 g) in 1983 in the Netherlands and to compare their reproductive outcomes with the total population at a similar age of 28 years. Young adults who were born after a pregnancy complicated by very preterm (VP) delivery or with a very low birth weight (VLBW) in the Netherlands in 1983 (Project on Preterm and Small for Gestational Age Infants (POPS) cohort) were invited to complete an online questionnaire at the age of 28. In total, 293 POPS-28 participants (31.6 %) completed the questionnaire including 185 female and 108 male participants. Female and male participants who were born VP or with a VLBW had significant reduced reproductive rates compared to the total Dutch population at 28 years of age (female 23.2 vs 31.9 % and male 7.4 vs 22.2 %). Pregnancies of the female participants were in 14 % complicated by preterm delivery in at least one pregnancy. Conclusion: This study indicates that women and men born VP or with a VLBW have reduced reproductive rates at the age of 28 compared to the total Dutch population at a similar age. [ABSTRACT FROM AUTHOR]

Objective: Neonatal resuscitation is often retrospectively documented, which can lead to inaccuracy and incomplete recording of delivery room management. In this study, we assessed the accuracy and completeness of neonatal resuscitation documentation in our neonatal intensive care unit. Methods: Recordings of physiological parameters and video data were performed in the delivery room and used to deduct the clinical condition of the infant, the interventions done and their effect on the infant's condition. The data from the recordings were compared with the documentation on neonatal stabilisation in the medical records ( paper or digital). Results: Recordings of 54 infants were compared with the documentation in their medical records. In 93% of the medical records delivery room management was documented. The clinical condition of the infant at birth was documented in 76% and 1 min Apgar scores in 98%. Respiratory support was correctly documented in 83%, heart rate in 37% and oxygen saturation in 13%. In 57% use of supplemental oxygen and its indication were correctly reported. Seven infants were intubated and this was correctly documented in 57%. Apgar scores were compared between the recordings and the medical records. At 1 min, 5 min and 10 min after birth the Apgar score, given by the researcher using the recordings, was similar to the scores in the medical records in 33%, 44% and 53%, respectively. Conclusions: Accurate and complete documentation of neonatal resuscitation continues to be a challenge. Recordings of physiological parameters and video imaging can improve documentation by providing detailed information. [ABSTRACT FROM AUTHOR]

The corrosion behavior as well as the microstructure in initial state and after corrosive deterioration were investigated for the newly developed Mg-Al-Ba-Ca alloy DieMag422. In order to investigate the corrosion behavior, potentiodynamic polarization measurements and immersion tests were performed in different NaCl concentrations. The microstructure was observed using light microscopy and combined SEM and EDX studies of the specimens before and after corrosive deterioration. Potentiodynamic polarization measurements and immersion tests showed that DieMag422 has a strong susceptibility to corrosion in NaCl solutions. Light microscope and SEM studies revealed that the difference in the corrosion behavior can be attributed to the different occurrence of the anodic α-Mg phase and the cathodic Ca-rich phase. [ABSTRACT FROM AUTHOR]

Background Neonates after perinatal asphyxia are at increased risk of thrombocytopenia. The correlation between perinatal asphyxia and the risk and severity of early-onset thrombocytopenia is not well known. Objective To estimate the incidence, severity and risk factors for early-onset thrombocytopenia in neonates after perinatal asphyxia. Methods We included all newborns (gestational age ≥ 36 weeks) admitted to our neonatal nursery due to perinatal asphyxia in this retrospective study. We collected platelet counts that were obtained within the first 48 h of life to estimate the incidence and severity of early-onset thrombocytopenia. Results A total number of 171 neonates with perinatal asphyxia were included in the study. The incidence of early-onset thrombocytopenia (platelet count < 150 × 109/l) was 51% (87/171). Several factors were associated with increased risk of early-onset thrombocytopenia, including prolonged prothrombin time ( PT) [odds ratio ( OR) 1·18, 95% confidence interval ( CI) 1·08-1·30, P < 0·01], prolonged activated partial thromboplastin time ( APTT) ( OR 1·07, 95% CI 1·03-1·11, P < 0·01), low Apgar score at 10 min ( OR 1·25, 95% CI 1·08-1·45, P < 0·01) and high serum lactate ( OR 1·12, 95% CI 1·06-1·19, P < 0·01). After multiple logistic regression analysis, we found an independent association between early-onset thrombocytopenia and prolonged PT ( OR 1·15, 95% CI 1·00-1·33, P = 0·045) and higher lactate level ( OR 1·15, 95% CI 1·03-1·28, P = 0·01). Conclusions Early-onset thrombocytopenia occurs frequently in neonates after perinatal asphyxia and is independently associated with PT and lactate level. [ABSTRACT FROM AUTHOR]

Background and Objectives Ferritin levels are often highly elevated at birth in neonates with alloimmune haemolytic disease of the fetus and newborn ( HDFN). Data on ferritin levels in these infants in the first 3 months of life are lacking. Objective of this study was to examine the course of iron status and incidence of iron deficiency and overload in neonates with alloimmune HDFN up to 3 months of age. Secondary objective was to analyse bilirubin levels, liver enzymes and red-blood-cell indices in the same time period and the association with intrauterine transfusion ( IUT). Materials and Methods Observational study of neonates with alloimmune HDFN admitted to our centre between November 2010 and March 2012. Data on iron status, bilirubin levels, liver enzymes and red-blood-cell indices up to 3 months of age were routinely collected and compared between neonates treated with and without IUT. Results Thirty-five infants with alloimmune HDFN were included. Iron overload occurred in 70% of neonates at birth and in 50% and 18% at the age of 1 and 3 months, respectively. No cases of iron deficiency at birth and only one case of iron deficiency at 3 months of age were found. No infants received iron therapy. Infants who received IUT had a significantly lower haemoglobin level and reticulocyte count and higher ferritin level at birth. Conclusion The vast majority of neonates with alloimmune HDFN have iron overload at birth. Incidence of iron overload gradually decreases within the first 3 months without iron supplementation. [ABSTRACT FROM AUTHOR]

Apnoea of prematurity is treated with noninvasive respiratory therapy and methylxanthines. For therapy unresponsive apnoea doxapram is often prescibed in preterm neonates. The duration, dosage and route of administration of doxapram together with its efficacy was evaluated in two Dutch neonatal intensive care. Outcome concerning short-term safety and neonatal morbidity were evaluated. During 5 years, 122 of 1,501 admitted newborns <32 weeks of gestational age received doxapram. 64.8% of patients did not need intubation after doxapram. 25% of treated neonates were <27 weeks of gestation. A positive response to doxapram therapy on apnoeawas associatedwith longer durationof doxapramusage (P < 0.001), lowermean doses (P < 0.003), and less days of intensive care (median 33 versus 42 days; P < 0.002). No patients died during doxapram therapy. Incidence of necrotizing enterocolitis, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity, persistent ductus arteriosus, or worsening of pulmonary condition did not increase during doxapramtherapy. Doxapramis frequently used for apnoea of prematurity, despite a lack of data on short-term efficacy and long-term safety. Until efficacy and safety are confirmed in prospective trials, doxapram should be used with caution. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To assess the reliability of radiologic identification using visual comparison of ante and post mortem paranasal sinus computed tomography (CT). Subjects and methods: The study was approved by the responsible justice department and university ethics committee. Four blinded readers with varying radiological experience separately compared 100 post mortem to 25 ante mortem head CTs with the goal to identify as many matching pairs as possible (out of 23 possible matches). Sensitivity, specificity, positive and negative predictive values were calculated for all readers. The chi-square test was applied to establish if there was significant difference in sensitivity between radiologists and non-radiologists. Results: For all readers, sensitivity was 83.7%, specificity was 100.0%, negative predictive value (NPV) was 95.4%, positive predictive value (PPV) was 100.0%, and accuracy was 96.3%. For radiologists, sensitivity was 97.8%, NPV was 99.4%, and accuracy was 99.5%. For non-radiologists, average sensitivity was 69.6%, negative predictive value (NPV) was 91.7%, and accuracy was 93.0%. Radiologists achieved a significantly higher sensitivity (p <0.01) than non-radiologists. Conclusions: Visual comparison of ante mortem and post mortem CT of the head is a robust and reliable method for identifying unknown decedents, particularly in regard to positive matches. The sensitivity and NPV of the method depend on the reader''s experience. [Copyright &y& Elsevier]

Objective To evaluate the incidence and severity of and risk factors for thrombocytopenia at birth in neonates with red cell alloimmunization. Study design All neonates with haemolytic disease of the foetus/newborn (HDFN) due to red cell alloimmunization admitted to our centre between January 2000 and September 2010 were included in this retrospective study. We measured platelet counts at birth and determined the incidence of thrombocytopenia (platelet count < 150 × 109/l) and severe thrombocytopenia (platelet count < 50 × 109/l). Risk factors for thrombocytopenia at birth were evaluated. Results Thrombocytopenia was present in 26% (94/362) of included neonates with HDFN at birth. Severe thrombocytopenia was found in 6% (20/362) of neonates. Three risk factors were found to be independently associated with thrombocytopenia at birth: treatment with intrauterine red cell transfusion (IUT) (OR 3·32, 95% CI 1·67-6·60, P = 0·001), small for gestational age (SGA) below the 10th percentile (OR 3·32, 95% CI 1·25-8·80, P = 0·016) and lower gestational age at birth (OR 1·22/week, 95% CI 1·02-1·44, P = 0·025). Conclusions Thrombocytopenia at birth occurs in 26% of neonates with HDFN due to red cell alloimmunization and is independently associated with IUT treatment, SGA and lower gestational age at birth. [ABSTRACT FROM AUTHOR]

Background: International neonatal resuscitation guidelines recommend assessing chest excursion when the heart rate is not improving. However, the accuracy in assessing 'adequate' chest excursion lacks objectivity. Aim: It was the aim of this study to test the accuracy in the assessment of 'adequate' chest excursion by measuring intra- and inter-observer variability of participants during simulated neonatal resuscitation. Methods: Thirty-seven staff members (8 neonatologists, 8 registrars, 21 nurses) of the Neonatal Intensive Care Unit, Leiden University Medical Center, Leiden, The Netherlands, ventilated 2 different intubated, leak-free manikins at 2 attempts, each with a different compliance. Blinded to the manometer, participants could change the peak inflation pressure until chest movement was adequate according to their perception. Inflating pressures were recorded. Results: According to the participants, a median (interquartile range) pressure of 18 cm H2O (16-22) at the first and 18 cm H2O (16-25) at the second attempt were needed to reach adequate chest excursion in the Laerdal manikin. The HAL manikin needed 26 cm H2O (19-31) and 24 cm H2O (22-33), respectively. The inter-observer coefficient of variance was 30% with the Laerdal manikin at both attempts, and 35 and 40% with the HAL manikin, respectively. The intra-observer coefficient of variance was 15% (8-23) with the Laerdal and 13% (9-20) with the HAL manikin. In both manikins and attempts, no significant differences in pressures and variances of pressures between the 3 groups were found. Conclusion: 'Adequate' chest excursion is a subjective parameter for guidance of appropriate ventilation during neonatal resuscitation. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

To evaluate neonatal outcome in Kell haemolytic disease compared to Rh D haemolytic disease. Retrospective study of all (near)-term neonates with Kell ( n = 34) and Rh D haemolytic disease ( n = 157) admitted to our centre between January 2000 and December 2008. We recorded the need for exchange transfusion and top-up transfusions up to 3 months of age. Neonates in the Kell group required less days of phototherapy than neonates in the Rh D group [2·4 vs. 4·1 days, respectively ( P < 0·01)]. The percentage of neonates requiring an exchange transfusion was lower in the Kell group than in the Rh D group [6% (2/34) and 62% (98/157), respectively ( P < 0·01)]. The percentage of neonates in the Kell group and Rh D group requiring a top-up transfusion was 62% (21/34) and 72% (113/157), respectively ( P = 0·20). The median number of top-up transfusions per neonate in the Kell group and Rh D group was 1 [interquartile range (IQR) 0-2] and 2(IQR 0-2), respectively ( P = 0·07). Neonates with Kell haemolytic disease require less phototherapy and less exchange transfusions compared to neonates with Rh D haemolytic disease, but an equal number of top-up transfusions. [ABSTRACT FROM AUTHOR]

Abstract: We present a case of an individual who stabbed himself through the heart with a large knife. Post mortem computed tomography (CT) and CT-angiography were used to assess the stab channel and to reconstruct the sequence of events. After penetrating injuries to the chest, both the intra-thoracic organs and the injury causing instrument may shift (e.g. from pnemothorax) and render forensic reconstructions more challenging. This case report illustrates the potentials and the pitfalls of CT for the reconstruction of penetrating injures to the chest. [Copyright &y& Elsevier]

Objective. To determine the incidence, management, complications, and outcome in neonates with thrombotic events. Study Design. We performed a retrospective study of all neonates with thrombotic events admitted to our neonatal intensive care unit from January 2004 to July 2010. Results. Thrombotic events were identified in 32 of 4734 neonates (0.7%). Seven neonates were managed expectantly and 25 neonates received anticoagulant treatment. Complete resolution of the clot within 3 months of age was found in 68% (17/25) of the treated and in 86% (6/7) of the nontreated neonates. Major complications due to anticoagulant therapy occurred in 3/25 cases (12%) and included severe hemorrhage (n = 2) and abscess at the injection site (n = 1). Conclusion. Complete or partial clot resolution in neonatal thrombosis occurred in both the treated group and nontreated group. Randomized controlled trials are warranted to determine the optimal management in neonatal thrombosis. [ABSTRACT FROM AUTHOR]

Objective To study the effect of a restrictive guideline for exchange transfusion (ET) on the number of top-up transfusions in neonates with Rh hemolytic disease. Study Design Retrospective study of all (near)-term neonates with Rh hemolytic disease admitted to our center between 2000 and 2008. In December 2005, policy changed from using liberal ET criteria to more restrictive ET criteria. We recorded the number of ETs and the number of top-up transfusions in the group of neonates before (group I, n = 156) and after (group II, n = 27) the guideline change. Results The percentage of neonates requiring an ET decreased from 66% (103/156) in group I to 26% (7/27) in group II ( P < 0·01). The percentage of neonates receiving a top-up transfusion increased from 68% (105/154) in group I to 81% (22/27) in group II ( P = 0·25). The median number of top-up transfusions increased from 1 (interquartile range 0–2) in group I to 2 (interquartile range 1–3) in group II ( P = 0·01). Conclusion In this study, restrictive ET criteria in neonates with Rh hemolytic disease lead to a reduction of the rate of ET but an increase in the number of top-up transfusions for neonatal anemia. [ABSTRACT FROM AUTHOR]

Monochorionic twins share a single placenta with intertwin vascular anastomoses, allowing the transfer of blood from one fetus to the other and vice versa. These anastomoses are the essential anatomical substrate for the development of several complications, including twin-twin transfusion syndrome (TTTS) and twin anemia-polycythemia sequence (TAPS). TTTS and TAPS are both chronic forms of fetofetal transfusion. TTTS is characterized by the twin oligopolyhydramnios sequence, whereas TAPS is characterized by large intertwin hemoglobin differences in the absence of amniotic fluid discordances. TAPS may occur spontaneously in up to 5% of monochorionic twins and may also develop after incomplete laser treatment in TTTS cases. This review focuses on the pathogenesis, incidence, diagnostic criteria, management options and outcome in TAPS. In addition, we propose a classification system for antenatal and postnatal TAPS. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Nano-indentation is an important technique to determine the Young modulus of multiphase materials where normal tensile tests are not appropriate. In this work, Ti-TiAl3 metallic-intermetallic laminate composites have been fabricated successfully in open atmosphere using commercial purity Al and Ti foils with 250 μm and 500 μm initial thicknesses, respectively. Sintering process was performed at 700 °C under 2 MPa pressure for 7.5 h. Mechanical properties including the Young modulus were determined after manufacturing. The Young moduli of metallic and intermetallic phases were determined as 89 GPa and 140 GPa, respectively. Microstructure analyses showed that aluminum foil was almost consumed by forming a titanium aluminide intermetallic compound. Titanium aluminides grow up through spherical shaped islands and metallic-intermetallic interface is a wavy form in Ti-Al system. Thus, the final microstructure consists of alternating layers of intermetallic compound and unreacted Ti metal. Microstructure and phase characterizations were performed by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. Hardness of test samples was determined as 600 HV for intermetallic zone and 130 HV for metallic zone by the Vickers indentation method. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate how a red blood cell transfusion volume of 15 or 20 mL kg−1 body weight affects the total number of administered transfusions and neonatal complications in premature infants born before 32 gestational weeks. In this observational study, we analysed clinical data from two cohorts of 218 and 241 premature infants admitted to two neonatal centres which used the same transfusion guideline and product, but different transfusion volumes. Outcome parameters were the number of administered transfusions and the composite outcome of bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular haemorrhage and mortality. The proportion of transfused infants was significantly lower (59 vs. 77%) in the centre using a lower transfusion volume of 15 mL kg−1. In infants born between a gestational age of 24 0/7 weeks and 27 6/7 weeks. a similar proportion received transfusions in both centres, with an equal number of transfusions per infant. In infants born between a gestational age of 28 0/7 weeks and 31 6/7 weeks, the proportion of transfused infants (49 vs. 74%) was significantly higher in the centre using a larger transfusion volume. In these infants, transfusion with 20 mL kg−1 resulted, however, in a mean reduction of one transfusion episode per infant. The higher proportion of transfused infants was associated with a higher pre-transfusion haematocrit in less ill infants, suggesting the use of different triggers based on clinical grounds. Composite clinical complications were similar in both cohorts. Clinical neonatal outcome was similar disregard of a higher proportion of transfused patients and a higher total amount of RBC transfused in one of the centres. A larger transfusion volume of 20 mL kg−1 prolonged the interval until next transfusion and can reduce donor exposure in infants born between a gestational age of 28 0/7 weeks and 31 6/7 weeks. [ABSTRACT FROM AUTHOR]