Temperature dependence of Vortex Charges in High Temperature Superconductors

Using a model Hamiltonian with d-wave superconductivity and competing antiferromagnetic (AF) interactions, the temperature (T) dependence of the vortex charge in high T_c superconductors is investigated by numerically solving the Bogoliubov-de Gennes equations. The strength of the induced AF order inside the vortex core is T dependent. The vortex charge could be negative when the AF order with sufficient strength is present at low temperatures. At higher temperatures, the AF order may be completely suppressed and the vortex charge becomes positive. A first order like transition in the T dependent vortex charge is seen near the critical temperature T_{AF}. For underdoped sample, the spatial profiles of the induced spin-density wave and charge-density wave orders could have stripe like structures at T < T_s, and change to two-dimensional isotropic ones at T > T_s. As a result, a vortex charge discontinuity occurs at T_s.Comment: 5 pages, 5 figure

Charged Vortices in High Temperature Superconductors Probed by NMR

We report a first experimental evidence that a vortex in the high temperature superconductors (HTSC) traps a finite electric charge from the high resolution measurements of the nuclear quadrupole frequencies. In slightly overdoped YBa_2Cu_3O_7 the vortex is negatively charged by trapping electrons, while in underdoped YBa_2Cu_4O_8 it is positively charged by expelling electrons. The sign of the trapped charge is opposite to the sign predicted by the conventional BCS theory. Moreover, in both materials, the deviation of the magnitude of the charge from the theory is also significant. These unexpected features can be attributed to the novel electronic structure of the vortex in HTSC.Comment: 6 pages, 7 figures, to be published in Phys Rev.

Research priorities in pediatric parenteral nutrition: a consensus and perspective from ESPGHAN/ESPEN/ESPR/CSPEN

Parenteral nutrition is used to treat children that cannot be fully fed by the enteral route. While the revised ESPGHAN/ESPEN/ESPR/CSPEN pediatric parenteral nutrition guidelines provide clear guidance on the use of parenteral nutrition in neonates, infants, and children based on current available evidence, they have helped to crystallize areas where research is lacking or more studies are needed in order to refine recommendations. This paper collates and discusses the research gaps identified by the authors of each section of the guidelines and considers each nutrient or group of nutrients in turn, together with aspects around delivery and organization. The 99 research priorities identified were then ranked in order of importance by clinicians and researchers working in the field using a survey methodology. The highest ranked priority was the need to understand the relationship between total energy intake, rapid catch-up growth, later metabolic function, and neurocognitive outcomes. Research into the optimal intakes of macronutrients needed in order to achieve optimal outcomes also featured prominently. Identifying research priorities in PN should enable research to be focussed on addressing key issues. Multicentre trials, better definition of exposure and outcome variables, and long-term metabolic and developmental follow-up will be key to achieving this. Impact: The recent ESPGHAN/ESPEN/ESPR/CSPEN guidelines for pediatric parenteral nutrition provided updated guidance for providing parenteral nutrition to infants and children, including recommendations for practice.However, in several areas there was a lack of evidence to guide practice, or research questions that remained unanswered. This paper summarizes the key priorities for research in pediatric parenteral nutrition, and ranks them in order of importance according to expert opinion

Chronic Intestinal Failure in Children: An International Multicenter Cross-Sectional Survey

Background: The European Society for Clinical Nutrition and Metabolism database for chronic intestinal failure (CIF) was analyzed to investigate factors associated with nutritional status and the intravenous supplementation (IVS) dependency in children. Methods: Data collected: demographics, CIF mechanism, home parenteral nutrition program, z-scores of weight-for-age (WFA), length or height-for-age (LFA/HFA), and body mass index-for-age (BMI-FA). IVS dependency was calculated as the ratio of daily total IVS energy over estimated resting energy expenditure (%IVSE/REE). Results: Five hundred and fifty-eight patients were included, 57.2% of whom were male. CIF mechanisms at age 1–4 and 14–18 years, respectively: SBS 63.3%, 37.9%; dysmotility or mucosal disease: 36.7%, 62.1%. One-third had WFA and/or LFA/HFA z-scores &lt; −2. One-third had %IVSE/REE &gt; 125%. Multivariate analysis showed that mechanism of CIF was associated with WFA and/or LFA/HFA z-scores (negatively with mucosal disease) and %IVSE/REE (higher for dysmotility and lower in SBS with colon in continuity), while z-scores were negatively associated with %IVSE/REE. Conclusions: The main mechanism of CIF at young age was short bowel syndrome (SBS), whereas most patients facing adulthood had intestinal dysmotility or mucosal disease. One-third were underweight or stunted and had high IVS dependency. Considering that IVS dependency was associated with both CIF mechanisms and nutritional status, IVS dependency is suggested as a potential marker for CIF severity in children

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p

International Society of Sports Nutrition Position Stand: Probiotics.

Position statement: The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of probiotic supplementation to optimize the health, performance, and recovery of athletes. Based on the current available literature, the conclusions of the ISSN are as follows: 1)Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host (FAO/WHO).2)Probiotic administration has been linked to a multitude of health benefits, with gut and immune health being the most researched applications.3)Despite the existence of shared, core mechanisms for probiotic function, health benefits of probiotics are strain- and dose-dependent.4)Athletes have varying gut microbiota compositions that appear to reflect the activity level of the host in comparison to sedentary people, with the differences linked primarily to the volume of exercise and amount of protein consumption. Whether differences in gut microbiota composition affect probiotic efficacy is unknown.5)The main function of the gut is to digest food and absorb nutrients. In athletic populations, certain probiotics strains can increase absorption of key nutrients such as amino acids from protein, and affect the pharmacology and physiological properties of multiple food components.6)Immune depression in athletes worsens with excessive training load, psychological stress, disturbed sleep, and environmental extremes, all of which can contribute to an increased risk of respiratory tract infections. In certain situations, including exposure to crowds, foreign travel and poor hygiene at home, and training or competition venues, athletes' exposure to pathogens may be elevated leading to increased rates of infections. Approximately 70% of the immune system is located in the gut and probiotic supplementation has been shown to promote a healthy immune response. In an athletic population, specific probiotic strains can reduce the number of episodes, severity and duration of upper respiratory tract infections.7)Intense, prolonged exercise, especially in the heat, has been shown to increase gut permeability which potentially can result in systemic toxemia. Specific probiotic strains can improve the integrity of the gut-barrier function in athletes.8)Administration of selected anti-inflammatory probiotic strains have been linked to improved recovery from muscle-damaging exercise.9)The minimal effective dose and method of administration (potency per serving, single vs. split dose, delivery form) of a specific probiotic strain depends on validation studies for this particular strain. Products that contain probiotics must include the genus, species, and strain of each live microorganism on its label as well as the total estimated quantity of each probiotic strain at the end of the product's shelf life, as measured by colony forming units (CFU) or live cells.10)Preclinical and early human research has shown potential probiotic benefits relevant to an athletic population that include improved body composition and lean body mass, normalizing age-related declines in testosterone levels, reductions in cortisol levels indicating improved responses to a physical or mental stressor, reduction of exercise-induced lactate, and increased neurotransmitter synthesis, cognition and mood. However, these potential benefits require validation in more rigorous human studies and in an athletic population

Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study

BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P &lt; 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P &lt; 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223

Bernoulli Potential in Superconductors. How the Electrostatic Field Helps to Understand Superconductivity

{1}History of the Bernoulli potential}{1} {1.1}Magneto-hydrodynamics}{1} {1.2}Thermodynamical forces}{1} {1.3}Surface dipole}{3} {1.4}Non-local theory}{4} {1.5}Field effect on the superconductivity}{4} References {2}Basic concepts}{7} {2.1}Maxwell equations}{7} {2.1.1}Electromagnetic potentials}{8} {2.1.2}Coulomb gauge}{9} {2.1.3}Equation of continuity}{10} {2.2}Material relations in normal metals}{11} {2.2.1}Ohm law}{9} {2.2.2}Hall effect}{11} {2.2.3}Drift in crossed electric and magnetic fields}{14} {2.3}Material relations in superconductors}{15} {2.3.1}Magneto-hydrodynamical picture}{13} {2.3.2}London theory}{18} {2.3.3}London penetration depth}{20} {3}Balance of forces}{21} {3.1}Bernoulli potential}{21} {3.1.1}Close to the charge neutrality}{22} {3.1.2}Transient period}{23} {3.2}Surface charge}{24} (3.2.1}Diamagnetic current versus drift}{24} {3.2.2}Surface charge}{25} {3.2.3}Thomas-Fermi screening}{25} {3.3}Finite temperatures}{29} {3.3.1}London penetration depth}{29} {3.3.2}Quasi-particle screening}{29} {3.4}Lorentz force}{31} {3.4.1}Magnetic pressure}{32} {4}Thermodynamical correction}{35} {4.1}Theory of Rickayzen}{35} {4.1.1}Gibbs electro-chemical potential}{36} {4.1.2}Local approximation of free energy}{37} {4.1.3}Thermodynamical corrections}{39} {4.2}Measurements of Bernoulli potential}{40} {4.2.1}Standard Hall bar setup}{41} {4.2.2}Kelvin capacitive pickup}{42} {Bernoulli potential first observed}{44} {High-precission measurements of the Bernoulli potential}{45} {4.2.3}Charge transfer in the superconductor}{48} {5}Phenomenological description}{51} {5.1}Thermodynamic relations}{52} {5.1.1}Free energy of a normal metal}{53} {5.1.2}Free energy of a superconductor}{54} {5.2}Two-fluid model}{55} {5.3}Currents in the two-fluid model}{57} {5.3.1}Extended London theory}{57} {5.4}Electrostatic potential}{59} {5.4.1}Free energy for the Coulomb interaction}{60} {5.5}The two fluid model with the electric field}{61} {5.5.1}Stability conditions alias Equations of motion}{61} {5.5.2}Thomas-Fermi screening}{62} {5.5.3}Thermodynamical correction of Rickayzen}{63} { {6}Non-local corrections}{67} {6.1}Preliminary assumptions}{67} {6.1.1}Intermediate states}{67} {6.1.2}Magnetism of atoms}{69} {Paramagnetic mechanism}{70} {Diamagnetic mechanism}{70} {Diamagnetic current}{71} {6.2}Wave function for super-electrons}{72} {6.2.1}Free energy with quantum features}{73} {6.2.2}Neglect of surface free energy}{73} {6.2.3}From kinetic energy to gradient corrections}{74} {6.3}Free energy}{75} {6.3.1}Original free energy of Ginzburg and Landau}{76} {7}Extended Ginzburg-Landau theory}{79} {7.1}Maxwell equations}{79} {7.1.1}Poisson equations}{79} {7.1.2}Ampere law}{80} {7.2}Ginzburg-Landau equation}{81} {7.2.1}Variation with complex variables}{81} {7.2.2}Equation of Schr\"odinger type}{82} {Quantum kinetic energy}{82} {Equation for the wave function}{83} {Boundary condition}{83} {Effective potential for super-electrons}{84} {7.3}Scalar potential}{86} {8}Quasi-neutral limit}{89} {8.1}Iterative treatment}{89} {8.1.1}Zeroth order in the charge transfer}{89} {8.1.2}Bernoulli potential in the first order}{90} {8.1.3}Estimate of the charge density}{91} {Scheme of iterations}{92} {8.2}Continuity of super-current}{92} {8.3}Anderson theorem}{93} {8.4}Interaction with the magnetic field}{95} {8.4.1}Phase transition in a very thin slab}{95} {8.4.2}Little-Parks effect}{97} {9}Diamagnetic current at surface}{103} {9.1}Geometrical assumptions}{103} {9.2}Low magnetic fields}{105} {9.2.1}Zero magnetic field}{105} {9.2.2}Linear order in the magnetic field}{106} {9.3}Perturbations in the quadratic order}{106} {9.3.1}GL wave function}{107} {9.3.2}Bernoulli potential}{109} {9.3.3}Surface charge}{110} {9.3.4}Bernoulli potential at the surface}{111} {9.3.5}Space profile of the Bernoulli potential}{112} {9.3.6}Charge profile}{114} {9.4}Strong magnetic field}{115} {9.4.1}Magnetic field in third order response}{115} {9.4.2}Magnetic field effect on the penetration depth}{116} {9.5}Numerical results}{118} {10}Surfaces}{123} {10.1}Ground state energy for normal electrons}{124} {10.1.1}Density of free electrons}{125} {10.1.2}Kinetic energy of free electrons}{125} {10.1.3}Gradient correction of Weizs\"acker}{126} {10.1.4}Complete energy of the normal ground state}{127} {10.2}Equations for charge profile}{128} {10.2.1}Local approximation}{128} {10.2.2}Screening in the local approximation}{129} {10.2.3}Tunnelling into the vacuum}{130} {10.2.4}Surface dipole}{131} {10.3}Budd-Vannimenus theorem}{132} {10.3.1}Identity for the surface potential}{133} {10.3.2}Surface dipole of superconductor}{134} {10.3.3}Magnetic field effect on the work function}{135} {10.3.4}Electrostatic potential seen by capacitive pickup}{136} {11}Matching of electrostatic potentials at surfaces}{139} {11.1}Surface dipole on the intermediate scale}{139} {11.2}Surface potential step in local approximations}{142} {11.2.1}London theory}{142} {11.2.2}Theory of van\nobreakspace {}Vijfeijken and Staas}{143} {11.2.3}Theory of Rickayzen}{144} {11.3}Matching for the Ginzburg-Landau theory in the quasi-neutral limit}{145} {11.3.1}Integral of motion for the slab geometry}{146} {11.3.2}Electrostatic potential at surface}{148} {11.4}Matching for the Ginzburg-Landau theory}{148} {11.4.1}Integral of motion for the slab geometry -- general case}{148} {11.4.2}Gradient terms}{150} {11.4.3}Electrostatic potential at the surface}{151} {12}Diamagnetic currents deep in the bulk}{155} {12.1}Nucleation of superconductivity}{156} {12.1.1}Linearized GL theory}{156} {12.1.2}Nucleation magnetic field $B_{\rm c2}$}{157} {12.2}Vortex}{158} {12.2.1}Vortex position}{160} {12.2.2}Elementary magnetic flux}{161} {12.3}Abrikosov vortex lattice}{161} {12.3.1}Condensate and magnetic field}{162} {12.3.2}Electrostatic potential}{165} {12.3.3}Comparing forces on super-electrons}{166} {12.3.4}Charge transfer}{167} {13}Electrostatic potential above a surface with vortices}{171} {13.1}Potential on the surface}{171} {13.1.1}Comparing surface and bulk potentials}{174} {13.1.2}Estimates of the surface potential}{175} {13.2}Potential at finite distance from the surface}{176} {13.2.1}Poisson equation and boundary conditions}{176} {13.2.2}Potential above the Abrikosov lattice}{176} {13.3}Charge transfer at the surface}{178} {13.3.1}Surface charge}{178} {13.3.2}Surface dipole}{179} {13.4}Electric field above the Abrikosov vortex lattice}{180} {14}Layered structures}{183} {14.1}Cutting the space in slices}{184} {14.1.1}Layer GL wave function}{185} {14.1.2}Layer condensation energy}{185} {14.1.3}In-layer kinetic energy}{186} {14.1.4}Josephson coupling}{187} {14.1.5}Electron free energy in the layered system}{188} {14.1.6}Condition of stability}{188} {14.2}Lawrence-Doniach model of YBa$_2$Cu$_3$O$_7$}{190} {14.2.1}Condensation energy}{191} {14.2.2}Kinetic energy}{191} {14.2.3}Electromagnetic interaction}{192} {14.3}Equations of motion}{193} {14.3.1}Maxwell equation}{193} {14.3.2}Lawrence-Doniach equations}{194} {14.3.3}Electrostatic potential}{194} {15}Charge transfer in layered structures}{197} {15.1}Perpendicular magnetic field}{197} {15.1.1}Ginzburg-Landau equations}{198} {15.1.2}Effective Ginzburg-Landau equation}{198} {15.1.3}Mapping on a metal}{199} {15.2}Charge transfer in the YBa$_2$Cu$_3$O$_7$}{200} {15.2.1}Electrostatic potential of a single layer}{201} {15.2.2}Electrostatic potential of identically perturbed layers}{202} {15.2.3}Charge transfer}{203} {15.3}Close to the critical temperature}{204} {15.3.1}Electrostatic potential}{204} {15.3.2}Quasi-neutral approximation}{204} {15.3.3}Beyond the quasi-neutrality}{206} {15.4}Charge transfer effect on the nuclear resonance}{207} {15.4.1}Energy levels of nucleon}{207} {15.4.2}Frequencies of the nuclear magnetic resonance}{208} {16}Effect of the electrostatic field on the superconductor}{211} {16.1}Weakly screening materials}{211} {16.1.1}Penetration of the electric field}{211} {16.1.2}Weakly screened penetrating electrostatic potential}{212} {16.1.3}Effect of the surface charge on superconductivity}{213} {16.1.4}Increased temperature of the phase transition}{214} {16.2}Strong screening}{216} {16.2.1}Contribution of the surface dipole to the penetration depth}{216} {16.2.2}Reduced charge perturbation behind the surface dipole}{217} {16.2.3}Field effect on the GL wave function}{218} {16.3}Effective boundary condition}{219} {16.3.1}Characteristic potential of the field effect}{221} {16.3.2}Phase transition in thin layers under bias}{223} {16.3.3}Reduced transition temperature of thick layers}{225} {16.3.4}Field-induced surface superconductivity}{226} {17}Outlook and perspectives}{229} {A}Estimate of material parameters}{231} {A.1}Coefficient $\partial \gamma /\partial n$}{231} {A.1.1}Models of free electrons}{232} {A.1.2}Increase of $\gamma$ due to interaction with lattice vibrations}{233} {A.2}Coefficient $\partial \varepsilon _{\rm con}/\partial n$}{233} {A.2.1}The BCS estimate}{234} {A.2.2}McMillan formula}{235} {A.3}Material parameters of Niobium}{236} {B}Numerical solution}{241} {B.1}Dimensionless notation}{241} {B.2}Fourier representation}{243} {B.3}Simple iteration scheme}{244} {B.4}Accelerated iteration scheme}{244} {B.5}Description of the Ginzburg-Landau program}{245} {C}Internal versus applied magnetic field}{251} {C.1}Virial theorem}{251} {C.2}Magnetic properties of the GL theory}{253} {C.3}Magnetic properties of the extended GL theory}{254} {References}{257} {Index}{263

Supplementation of N-3 LCPUFA to the diet of children older than 2 years: a commentary by the ESPGHAN Committee on Nutrition.

The aim of this commentary is to review data on the effect of supplementation of paediatric patients ages 2 years or older with n-3 long-chain polyunsaturated fatty acids (LCPUFA). Some evidence for a positive effect on functional outcome in children with attention-deficit/hyperactivity disorder (ADHD) was found; however, benefit was seen in only about half of the randomised controlled trials (RCT), and studies varied widely not only in dose and form of supplementation but also in the functional outcome parameter tested. The committee concludes that there are insufficient data to recommend n-3 LCPUFA supplementation in the treatment of children with ADHD, but further research on n-3 LCPUFA supplementation in ADHD may be worthwhile. The committee was unable to find evidence of a favourable effect of n-3 LCPUFA supplementation on cognitive function in children. Although no benefit of n-3 LCPUFA supplementation was seen for major clinical outcome parameters in children with cystic fibrosis, a potentially beneficial shift towards less-inflammatory eicosanoid profiles seen in 2 studies provides grounds for further investigation; it is possible that earlier and longer supplementation periods may be needed to demonstrate clinical effect. For children with phenylketonuria, the limited data available suggest that supplementation of n-3 LCPUFA to the diet is both feasible and safe, but offers only transient benefit in visual function. For children with bronchial asthma there are insufficient data to suggest that LCPUFA supplementation has a beneficial effect. The committee advises paediatricians that most health claims about supplementation of n-3 LCPUFA in various diseases in children and adolescents are not supported by convincing scientific data