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Children comprise approximately 22% of the population in the United States.1 In a widespread disaster such as a hurricane, pandemic, wildfire or major earthquake, children are at least proportionately affected to their share of the population, if not more so. They also have unique vulnerabilities including physical, mental, and developmental differences from adults, which make them more prone to adverse health effects of disasters.2–4 There are about 5000 pediatric critical care beds and 23 000 neonatal intensive care beds out of 900 000 total hospital beds in the United States.5 While no mechanism exists to consistently track pediatric acute care beds nationally (especially in real time), a previous study6 showed a 7% decline in pediatric medical-surgical beds between 2002 and 2011. This study also estimated there are about 30 000 acute care pediatric beds nationally. Finding appropriate hospital resources for the provision of care for pediatric disaster victims is an important concern for those charged with triaging patients in a major event.

LiMn2O4 is a battery cathode material with desirable properties such as low cost, low toxicity, high natural abundance of Mn, and environmental compatibility. By means of first-principles calculations, we study the structural, magnetic, and electronic properties of LiMn2O4 under ambient conditions and high hydrostatic pressures (until 20 GPa). We obtain two oxidation states for Mn, even using a cubic structure, which differ in all analyzed properties: structural, electronic, and magnetic. At P > 0, such properties were found to display a standard behavior decreasing smoothly and linearly with pressure. Furthermore, the enthalpy of cubic and orthorhombic structures under low and high-pressure conditions were examined, showing that no cubic to orthorhombic phase transition exists in all the investigated pressure range, nor is a magnetic cubic to a non-magnetic cubic phase transition possible.

The tokamak a configuration variable (TCV) continues to leverage its unique shaping capabilities, flexible heating systems and modern control system to address critical issues in preparation for ITER and a fusion power plant. For the 2019-20 campaign its configurational flexibility has been enhanced with the installation of removable divertor gas baffles, its diagnostic capabilities with an extensive set of upgrades and its heating systems with new dual frequency gyrotrons. The gas baffles reduce coupling between the divertor and the main chamber and allow for detailed investigations on the role of fuelling in general and, together with upgraded boundary diagnostics, test divertor and edge models in particular. The increased heating capabilities broaden the operational regime to include T (e)/T (i) similar to 1 and have stimulated refocussing studies from L-mode to H-mode across a range of research topics. ITER baseline parameters were reached in type-I ELMy H-modes and alternative regimes with `small' (or no) ELMs explored. Most prominently, negative triangularity was investigated in detail and confirmed as an attractive scenario with H-mode level core confinement but an L-mode edge. Emphasis was also placed on control, where an increased number of observers, actuators and control solutions became available and are now integrated into a generic control framework as will be needed in future devices. The quantity and quality of results of the 2019-20 TCV campaign are a testament to its successful integration within the European research effort alongside a vibrant domestic programme and international collaborations.

Objective Increased soluble levels of complement effectors have been demonstrated in active anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), but the timing of complement activation in the autoimmune inflammation remains elusive. This study investigated whether the complement system is activated before onset of symptoms in AAV. Method The Swedish National Patient Register and Cause of Death register were linked to registers of five biobanks to identify individuals sampled before AAV symptom onset. Diagnosis of AAV and time-point for symptom onset were confirmed by reviewing medical records. We identified 64 presymptomatic individuals with serum samples > 1 month < 10 years from AAV symptom onset and 122 matched controls. Complement factors (C2, C5) and activation markers (C5a, C4b) were measured using Luminex technology. Results Presymptomatic individuals had higher levels of C5 up to 6.5 years before symptom onset, compared with controls [median (IQR) 80.7 (131.9) vs 46.6 (63.4) mu g/mL, p = 0.05]. Levels of C5a increased significantly during the pre-dating time (p = 0.033) until symptom onset. The complement levels were significantly higher in presymptomatic myeloperoxidase (MPO)-ANCA(+) individuals versus MPO-ANCA(-) and proteinase-3-ANCA(+) individuals. C5 was significantly increased in cases with renal involvement at diagnosis versus controls (p = 0.022), whereas levels of both C5 and C5a were significantly increased in presymptomatic individuals diagnosed with microscopic polyangiitis after onset compared with controls (C5: p = 0.027; C5a: p = 0.027). Conclusion Activation of the complement system is an early event in the pathogenesis of AAV and is mainly associated with MPO-ANCA(+) AAV and with microscopic polyangiitis.

Tomography technology is not usual when investigating drilled asphalt cores properties. Currently, there is no internationally recognised standard tomography method for asphalt pavements. Tomography provides, however, a non-destructive alternative to traditional, usually destructive, testing of drilled cores. Furthermore, tomography offers possibilities, which traditional laboratory analyses do not. It is not straightforward to distinguish mastic and aggre- gates in tomography results while air void content is less difficult to assess. To have a more reliable assessment of drilled cores properties found by tomography, the method must be carefully planned, executed, and the results compared to those of traditional laboratory methods. In this work, analysis was carried out using six in-situ drilled cores from a double layered porous asphalt pavement. This allowed a comparison of tomography and a standardised conventional laboratory air void measurement on the exact same samples. Comparisons of the air voids found by tomography in all three directions were also carried out, estimating how anisotropic and heterogeneous the samples are, which is not possible using traditional laboratory tests. As few as four tomography slices can give enough precision in the determination of air void content for the porous layers. No more than eight slices per sample were needed in the suggested tomog- raphy method. The statistical results did not indicate that the air void content determined by tomography is different from the laboratory results.

Acta materialia 237, 118160 (2022). doi:10.1016/j.actamat.2022.118160, The influence of changes induced by ion irradiation on structure and thermal stability of metastable cubic (Ti,Al)N coatings deposited by cathodic arc evaporation is systematically investigated by correlating experiments and theory. Decreasing the nitrogen deposition pressure from 5.0 to 0.5 Pa results in an ion flux-enhancement by a factor of three and an increase of the average ion energy from 15 to 30 eV, causing the stress-free lattice parameter to expand from 4.170 to 4.206 Å, while the chemical composition of Ti$_{0.27}$Al$_{0.21}$N$_{0.52}$ remains unchanged. The 0.9% lattice parameter increase is a consequence of formation of Frenkel pairs induced by ion bombardment, as revealed by density functional theory (DFT) simulations. The influence of the presence of Frenkel pairs on the thermal stability of metastable Ti$_{0.27}$Al$_{0.21}$N$_{0.52}$ is investigated by scanning transmission electron microscopy, differential scanning calorimetry, atom probe tomography and in-situ synchrotron X-ray powder diffraction. It is demonstrated that the ion flux and ion energy induced formation of Frenkel pairs increases the thermal stability as the Al diffusion enabled crystallization of the wurtzite solid solution is retarded. This can be rationalized by DFT predictions since the presence of Frenkel pairs increases the activation energy for Al diffusion by up to 142%. Hence, the thermal stability enhancement is caused by a hitherto unreported mechanism - the Frenkel pair impeded Al mobility and thereby retarded formation of wurtzite solid solution., Published by Elsevier Science, Amsterdam [u.a.]

Create an easy-to-use pediatric out-of-hospital cardiac arrest (OHCA)-specific chart review tool to reliably detect severe adverse safety events (ASEs) in the prehospital care of children with OHCA.We revised our previously validated pediatric prehospital adverse event detection system (PEDS) tool, used to evaluate ASEs in the prehospital care of children during emergent calls, to create an OHCA-specific chart review tool. We developed decision support for reviewers, reviewer training, and a dedicated section for chart data abstraction. We randomly selected 28 charts for independent review by 2 expert reviewers who determined the presence or absence of a severe ASE for each care episode and identified the domain of care and preventability for each ASE. We calculated inter-rater agreement in the assessment of the presence or absence of a severe ASE using Gwet's first-order agreement coefficient (AC1).The PEDS-OHCA chart review tool has 6 sections, with a minimum of 70 and maximum of 667 total possible fields. We found inter-rater agreement of 0.83 (95% confidence interval, 0.63-0.99) between our 2 reviewers for the overall detection of a severe ASE and an average time to complete of 8 minutes (range, 2-25 minutes). Inter-rater agreement in the detection of a severe ASE in each individual domain ranged from 0.36 to 0.96.The PEDS-OHCA is the first chart review tool to systematically evaluate the safety and quality of EMS care for children with OHCA. This tool may help improve understanding of the quality of EMS care for children with OHCA, which is essential to improving outcomes.

Ultrafast manipulation of magnetism bears great potential for future information technologies. While demagnetization in ferromagnets is governed by the dissipation of angular momentum(1-3), materials with multiple spin sublattices, for example antiferromagnets, can allow direct angular momentum transfer between opposing spins, promising faster functionality. In lanthanides, 4f magnetic exchange is mediated indirectly through the conduction electrons(4) (the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction), and the effect of such conditions on direct spin transfer processes is largely unexplored. Here, we investigate ultrafast magnetization dynamics in 4f antiferromagnets and systematically vary the 4f occupation, thereby altering the magnitude of the RKKY coupling energy. By combining time-resolved soft X-ray diffraction with ab initio calculations, we find that the rate of direct transfer between opposing moments is directly determined by this coupling. Given the high sensitivity of RKKY to the conduction electrons, our results offer a useful approach for fine tuning the speed of magnetic devices. By exploring ultrafast magnetization in several compounds with similar crystal structures but different 4f magnetic elements, the authors show that the Ruderman-Kittel-Kasuya-Yosida interaction controls the spin dynamics.

Background. Clinical studies have shown that radiotherapy can induce vascular disease at the site of exposure but is usually not clinically evident until years after treatment. We have studied irradiated human arteries and veins to better understand the underlying biology in search of future treatments. The aim was to investigate whether radiotherapy contributed to a sustained expression of plasminogen activator inhibitor-1 (PAI-1) in human arteries and veins. Methods. Irradiated arteries and veins were harvested, together with unirradiated control vessels, from patients undergoing free tissue transfer reconstruction at a median time of 90 weeks [5–650] following radiation exposure. Differential gene expression of PAI-1 was analysed, together with immunohistochemistry (IHC) and immunofluorescence (IF). Results. PAI-1 gene expression was increased in both arteries (p=0.012) and veins (p<0.001) in irradiated compared to unirradiated control vessels. IHC and IF indicated that cells expressing PAI-1 were located in the adventitia of both arteries and veins and colocalized with cells positive for CD68, CD45, and α-SMA in arteries and with CD45 and α-SMA in veins. Conclusion. The current study shows a sustained upregulation of PAI-1 in both arteries and veins after exposure to ionizing radiation, indicating a chronic inflammation mainly in the adventitia. We believe that the results contribute to further understanding of radiation-induced vascular disease, where targeting PAI-1 may be a potential treatment.

Obtaining high quality, wurtzite InN films with p-type conductivity is a challenge, and there is limited information about the photoluminescence (PL) characteristics of such films. In this study, we present a comprehensive PL study and discuss in detail the recombination processes in Mg-doped InN films with varying Mg concentrations. We find that at low Mg-doping of 1x10(18) cm(-3), which yields p-type conductivity, the PL in InN is spatially inhomogeneous. The latter is suggested to be associated with the presence of n-type pockets, displaying photoluminescence at 0.73 eV involving electrons at the Fermi edge above the conduction band edge. Increasing the Mg concentration to 2.9x10(19) cm(-3) in p-type InN yields strong and spatially uniform photoluminescence at 0.62 eV and 0.68 eV visible all the way to room temperature, indicating homogeneous p-type conductivity. An acceptor binding energy of 64 meV is determined for the Mg acceptor. Further increase of the Mg concentration to 1.8x10(20) cm(-3) leads to switching conductivity back to n-type. The PL spectra in this highly doped sample reveal only the emission related to the Mg acceptor (at 0.61 eV). In the low-energy tail of the emission, the multiple peaks observed at 0.54 - 0.58 eV are suggested to originate from recombination of carriers localized at stacking faults. (C) 2019 Author(s). Funding Agencies|Swedish Research Council (VR) [2016-00889]; Swedish Governmental Agency for Innovation Systems (VINNOVA) under the Competence Center Program [2016-05190]; Swedish Foundation for Strategic Research (SSF) [FFL12-0181, RIF14-055, EM16-0024]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University, Faculty Grant SFO Mat LiU [2009-00971]

The chapter provides the reader with the basic understanding of process design and discusses few concepts important for consideration during this stage of the product lifecycle. The main focus of the chapter is on the downstream purification part of a manufacturing process. However, because the successful design of a downstream process always takes into account the various interdependencies between upstream and downstream parts, some important aspects of the upstream process design are also discussed. Throughout the chapter, an example of a universal roadmap for process and control strategy development is outlined and discussed by focusing on general rules and dedicated tools for developing, characterizing, and scaling-up of downstream processes. Generally applicable methodologies for sizing of filtration and chromatography unit operations are also outlined. Because the process design should also account for the functionality and limitations of commercial manufacturing equipment, examples of relevant constraints are given. The final section of this chapter discusses the use of various computational modeling strategies that could facilitate the design and scale-up of manufacturing processes.

Reversed phase chromatography (RPC) is a commonly used analytical method in the biotech and pharmaceutical industries. The technique also has an important place in preparative separations primarily in difficult polishing steps where other techniques cannot separate the desired product from closely related impurities.

Physical training has been shown to reduce mortality in normal subjects, and athletes have a healthier lifestyle after their active career as compared with normal subjects. Since the 1950s, the use of anabolic androgenic steroids (AAS) has been frequent, especially in power sports. The aim of the present study was to investigate mortality, including causes of death, in former Swedish male elite athletes, active 1960-1979, in wrestling, powerlifting, Olympic lifting, and the throwing events in track and field when the suspicion of former AAS use was high. Results indicate that, during the age period of 20-50 years, there was an excess mortality of around 45%. However, when analyzing the total study period, the mortality was not increased. Mortality from suicide was increased 2-4 times among the former athletes during the period of 30-50 years of age compared with the general population of men. Mortality rate from malignancy was lower among the athletes. As the use of AAS was marked between 1960 and 1979 and was not doping-listed until 1975, it seems probable that the effect of AAS use might play a part in the observed increased mortality and suicide rate. The otherwise healthy lifestyle among the athletes might explain the low malignancy rates. Language: en

Combining theory with experiments, we study the phase stability, elastic properties, electronic structure and hardness of layered ternary borides AlCr

Background: The impact of preoperative radiotherapy on microvascular reconstructive surgery outcome has been a subject of debate. However, data are conflicting and often dependent on local treatment protocols. We have studied the effects of radiotherapy in a unique, single-center setting where a treatment protocol change was undertaken from pre- to postoperative radiotherapy administration for microsurgical head and neck reconstructions. Methods: A cohort study was conducted for 200 consecutive head and neck free flap cases, where 100 were operated on before and 100 after the treatment protocol adjustment in 2006. Only direct cancer reconstructions were included. Complication rates of anastomosis-related (flap necrosis) and flap bed–related (infection, fistula, and wound dehiscence) complications were compared between irradiated and nonirradiated patients. A multivariate analysis was performed to correct for treatment period. Results: One hundred twenty-six patients had received radiotherapy before reconstruction due to cases of cancer recurrence. There were no significant differences in demographic data or risk factors between irradiated and nonirradiated cases. Irradiated cases had a higher rate of both flap loss (9.5% versus 1.4%; P = 0.034) and flap bed–related complications (29% versus 13%; P = 0.014). However, after multivariate analysis, there was only a significant relationship between preoperative irradiation and infection (odds ratio = 2.51; P = 0.033) and fistula formation (odds ratio = 3.13; P = 0.034). Conclusions: The current single-center study clearly indicates that preoperative radiotherapy is a risk factor for both infection and fistula formation, most likely related to an impaired flap bed. We suggest postoperative radiotherapy administration whenever possible for oncological reasons, otherwise proper antibiotic cover and meticulous flap insetting to prevent radiation-related infection and fistula formation.

Subjects with mild cognitive impairment associated with cortical amyloid-β have a greatly increased risk of progressing to Alzheimer’s disease. We hypothesized that neuroinflammation occurs early in Alzheimer’s disease and would be present in most amyloid-positive mild cognitive impairment cases. 11C-Pittsburgh compound B and 11C-(R)-PK11195 positron emission tomography was used to determine the amyloid load and detect the extent of neuroinflammation (microglial activation) in 42 mild cognitive impairment cases. Twelve age-matched healthy control subjects had 11C-Pittsburgh compound B and 10 healthy control subjects had 11C-(R)-PK11195 positron emission tomography for comparison. Amyloid-positivity was defined as 11C-Pittsburgh compound B target-to-cerebellar ratio above 1.5 within a composite cortical volume of interest. Supervised cluster analysis was used to generate parametric maps of 11C-(R)-PK11195 binding potential. Levels of 11C-(R)-PK11195 binding potential were measured in a selection of cortical volumes of interest and at a voxel level. Twenty-six (62%) of 42 mild cognitive impairment cases showed a raised cortical amyloid load compared to healthy controls. Twenty-two (85%) of the 26 amyloid-positive mild cognitive impairment cases showed clusters of increased cortical microglial activation accompanying the amyloid. There was a positive correlation between levels of amyloid load and 11C-(R)-PK11195 binding potentials at a voxel level within subregions of frontal, parietal and temporal cortices. 11C-(R)-PK11195 positron emission tomography reveals increased inflammation in a majority of amyloid positive mild cognitive impairment cases, its cortical distribution overlapping that of amyloid deposition.

– Size is a crucial factor affecting the survival of fish during winter. Pond and laboratory experiments with three size classes of perch (small: 40–70 mm, medium: 71–100 mm, large: 101–186 mm) revealed that the feeding history of perch prior to winter is reflected in the amount and type of accumulated energy reserves. The minimal amount of reserves was 2% of the perch’s biomass for fat and 9% for protein. An increase in glycogen levels either reflected mobilisation of energy in the body when perch were starving or an increase in accumulated energy over winter. In the laboratory, only the smallest perch suffered from high mortality rates, even if all were fed with low amounts of food. However, feeding the fish reduced the mortality rate after a certain time lag. Size-selective mortality rates occurred in the pond experiments as well. Small perch which survived the winter were able to rebuild their energy stores.

Using radio telemetry, the present study simulated the escape of 48 adult rainbow trout Oncorhynchus mykiss from a net-cage fish farm in the Lake Ovre Fryken, Sweden. The post-release dispersal of O. mykiss was fast, showed long-range dispersal behaviour, low winter survival and lacked the ability to find suitable spawning habitats. Thus, the present study suggested that reproducing for the first time may be an obstacle to the establishment of escaped farmed O. mykiss.

All 32 survivors with transposition of the great arteries, born in 1964-83 and operated on at our institution using atrial redirection, were evaluated by cardiac catheterization, echocardiography and Holter monitoring. There were 17 Mustard patients, age 17.1 years (±3.5, 12.0-22.0) and 15 Senning patients, age 9.4 years (±1.6, 7.2-12.1). All but one had simple transposition. Six had caval obstruction, one had pulmonary venous obstruction, three had large atrial shunts, four had considerable pulmonary hypertension, seven had mild ventricular outflow tract obstruction, four had significant tricuspid regurgitation, 11 had systemic ventricle dysfunction (one severe), 14 had sinus node dysfunction (three symptomatic) and two had atrioventricular block (one with pacemaker). Eight Mustard patients (47%) and one Senning patient (7%) had symptomatic cardiac sequelae, and only one patient (Senning) was free from sequelae, illustrating that these patient groups will need continuing medical attention.

This study concerns the technique electric field-assisted capillary liquid chromatography. In this technique, an electric field is applied over the separation capillary in order to provide an additional selectivity. In this technique, the electric field is applied in-line in the separation capillary and here the electric current is the factor limiting the magnitude of applied electric field. The influence of Joule heating and other factors on the current in such systems has been investigated. The temperature in the capillary was first measured within a standard CE set-up, as function of effect per unit of length. Then the same cooling system was applied to an in-line set-up, to replicate the conditions between the two systems, and thus the temperature. Thus Joule heating effects could then be calculated within the in-line system. It was found that for systems applying an electric field in line, the direct influence from Joule heating was only relatively small. The pH in the capillary was measured in the in-line set-up using cresol red/TRIS solutions as pH probe. Significant changes in pH were observed and the results suggested that electrolysis of water is the dominant electrode reaction in the in-line system. In summary, the observed conductivity change in in-line systems was found to be mainly due to the pH change by hydrolysis of water, but primarily not due the temperature change in the capillary column.

Background: The optimal training mode for cystic fibrosis (CF) patients has not been defined. Objective: This study aimed to investigate cardiopulmonary function before and after endurance (ET) or resistance training (RT) for 6 months. Methods: Twenty physically active adult patients (8 females) with classic CF were enrolled for ET or RT for 3 months followed by 3 months of mixed training. Training was recorded by telemetry and in diaries and lasted 30–45 min, three times a week. Lung function and peak oxygen uptake (VO2) were measured. Mean ± SD predicted percentage of forced expiratory volume in 1 s (FEV1 %) was 91 ± 21%; maximal workload (W) was 170 ± 31 in females and 273 ± 54 in males. Results: Nineteen patients completed the program, 3 at a lower and 1 at a higher training frequency than required. Maximal heart rate remained unchanged during the 6 months. Maximal VO2 (liters · min–1) was significantly correlated to FEV1 in males at baseline and 6 months (p = 0.006 and p = 0.04, respectively). Changes in maximal workload and maximal VO2 improved significantly with ET compared with RT. Conclusions: Physically active CF patients preserve good cardiopulmonary function into adulthood. The controlled training program did not lead to further improvement although ET induced larger changes than RT.

Objectives: The aim of this study was to investigate the relationship between anabolic androgenic steroids (AAS) and personality characteristics with the following research questions: 1) Do personality characteristics differ between AAS-abusers and an AAS-naive comparison group? 2) Do personality characteristics differ between active AASabusers and former AAS-abusers? 3) Does time of withdrawal from AAS affect personality characteristics? Design: Retrospective observational study. Methods: Sixty men (active n=20, former n=40) seeking medical consultation for their AAS abuse were included in the study. Personality characteristics were assessed by the Karolinska Scales of Personality (KSP) inventory. Comparisons were made with an age- and gender-matched group of AAS-naive body-builders (n=30). Results: AAS-abusers differed significantly in their personality characteristics from the AAS-naive control group. No major differences were found between active and former AAS-abusers. No correlations were found between personality characteristics and time of withdrawal or duration of AAS abuse. Conclusions: Individuals with AAS abuse differ in their personality characteristics from those who have never used AAS. Withdrawal from AAS does not, however, alter personality characteristic in AAS-abusers, although the causality of this relationship is unclear, indirectly stating that AAS do not seem to alter personality characteristics in a major fashion. On the other hand, it could be argued that AAS gives a more permanent change on personality that is not affected by time of withdrawal from AAS. Thus, the present results do not explain the causality of the relationship between AAS abuse and personality characteristics and further studies are needed in order to clarify this relationship.

We evaluated the concentrations of brain natriuretic peptide in the plasma as a marker of systolic ventricular function before and after maximal exercise in 15 surgically palliated patients with functionally univentricular hearts, with apparently good ventricular function. Of the patients, 6 with median age of 14.6 years, and a range from 12.5 to 17.9 years, had been palliated by construction of a total cavopulmonary connection, while the other 9 patients, with a median age of 32.1 years, and a range from 15.6 to 54.2 years, had undergone the classical Fontan procedure. We used 8 healthy individuals, with a median age of 13.9 years, and a range from 12.8 to 14.2 years, as a control group for the measurements of brain natriuretic peptide. The values of the peptide were significantly higher in those with the classical Fontan procedure, both before, when the median value was 131.8 nanogram per litre, with a range from 0.5 to 296.4, and after maximal exercise, when the median value was 108.1, with a range from 0.1 to 235.9. The comparable values in those with a total cavopulmonary connection were a median of 12.8, and a range from 0.5 to 39.1 before, and a median of 9.7, with a range from 2.7 to 26.2 after maximal exercise. The median value for the control group was 13.1, with a range from 2.6 to 38.7 before exercise (p = 0.016), and a median of 24.1, with a range from 5.8 to 66.7 after maximal exercise (p = 0.03), respectively. In the control subjects, the level of the peptide increased by a median of 9.7 nanograms per litre, with a range from 1.2 to 28.0 after maximal exercise (p = 0.008). The level was unchanged after maximal exercise in those with classical Fontan procedures and total cavopulmonary connections, with a difference between levels before and after exercise of a median of 5.9 nanogram per litre, and a range from −23.7 to 31.0 (p = 0.96), and a median of −1.0 nanogram per litre, with a range from −12.0 to 3.9 (p > 0.99), respectively. We conclude that maximal exercise did not increase the level of brain natriuretic peptide level in those patients with the classical Fontan procedure, nor those with a total cavopulmonary connection, findings which may indicate that systolic ventricular dysfunction is not the major cause of the decreased working capacity observed in patients with well functioning palliated functionally univentricular hearts.

Growth retardation is common in infants with congenital heart defects. The aim of this study was to investigate whether growth retardation or type of heart defect in infants with congenital heart defects is related to disturbances in lipid metabolism. Sixteen infants with ventricular septal defects and six infants with transposition of the great arteries were given an intravenous load of lipid emulsion (Intralipid® 20mg/ml) corresponding to 0.5 g fat/kg body weight for 5 min after fasting for 8h. Blood samples were drawn immediately before the infusion and 3, 20, 60, 120 and 240 min after the infusion was completed. Plasma concentrations of triglycerides (TG), free fatty acids (FFA), ketones, lactate, pyruvate, alanine, glycerol and glucose were determined. The fatty acid patterns in the TG and FFA fractions were measured using gas chromatography. Severe growth retardation in infants with defects of these kinds was correlated to higher fasting and maximum levels of linoleic acid in plasma FFA. The maximum levels of linoleic acid in the TG fraction were positively correlated to weight SD score, and maximum glycerol levels were higher in the most growth-retarded infants, indicating faster intravascular lipolysis. Linoleic acid in the TG fraction was still elevated at 120 and 240 min after the lipid load. Some differences between the cyanotic and VSD groups could be noted. These indicate decreased metabolic capacity to utilize released FFA in the cyanotic group. Infants with cyanotic heart defects also had higher lactate and alanine levels compared to infants with VSD. Our results support the hypothesis that lipid metabolism is disturbed in infants with congenital heart defects. □Congenital heart defect, free fatty acids, linoleic acid, lipids, lipolysis, metabolism, triglyceride

Magnetic resonance imaging (MRI) is the most widely used non-invasive test for assessing intra-articular injuries of the knee. It has been suggested that a negative MRI can be useful in avoiding the need for diagnostic arthroscopy in cases where clinical examination is equivocal. However, the sensitivity and specificity of MRI is not 100%, particularly for tears of the lateral meniscus. Furthermore, a false negative MRI scan may result in premature return to play in athletes, resulting in increased risk of further damage to a torn meniscus. To illustrate this issue, we present a case series of eight elite athletes who all presented with mechanical knee symptoms and where MRI scans revealed no significant intra-articular pathology. Five of the athletes were allowed to return to sport on the basis of a negative MRI. All patients were subsequently found to have a bucket-handle tear of their lateral meniscus at arthroscopy. Two independent, experienced musculoskeletal radiologists were asked to review the MRI films without being given any clinical history of the cases. Although injuries to the popliteus tendon were noted in two of the athletes who had sustained a recent acute injury to their knee, no meniscal tears were identified. Thus arthroscopy remains the gold standard for the assessment and management of high-demand patients with a clinical suspicion of meniscal pathology.

We present 3 cases of arthroscopically treated intraarticular osteoid osteoma of the ankle. Emphasis is on the high index of suspicion for this lesion, the appropriate imaging modality and the efficacy of arthroscopic excision of these tumors with superficial location in the talus and tibial plafond.