141 research outputs found
Charge profile in vortices
The electric charge density in the vortex lattice of superconductors is
studied within the Ginzburg-Landau theory. We show that the electrostatic
potential is proportional to the GL function,
. Numerical results for the triangular
vortex lattice are presented.Comment: 4 pages with 2 figure
Far-infrared magnetotransmission of YBa2(ZnxCu(1-x))3O(7-d)
Measurements of the far infrared magnetotransmission of
YBa2(ZnxCu(1-x))3O(7-d) thin film (x = 0.025) deposited on a wedged MgO
substrate are reported. The application of magnetic field perpendicular to the
ab plane produces at low temperature a linear increase of transmission for
frequencies below 30 cm-1. We present a model of high frequency vortex dynamics
which qualitatively explains these results.Comment: 2 pages with 2 figures, presented on LT2
Bernoulli potential at a superconductor surface
The electrostatic Bernoulli potential measured at the surface of a
superconductor via Kelvin capacitive coupling is shown to be independent of the
pairing mechanism. This contrasts with the Bernoulli potential in the bulk
where contributions due to pairing dominate close to .Comment: 2 page
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.
Early nutrition and adult health: Perspectives for international and community nutrition programs and policies
Recent economic changes throughout the world, either development or crises and recessions, have prompted a host of nutrition related problems, including a decreased prevalence of undernutrition, an increase in the prevalence of diet related diseases, widespread food insecurity as crop prices increase, and so on. In addition, evidence is mounting that suggests that exposure to poor nutrition early in life is a predisposing factor for chronic diseases in adulthood. Thus, the role of international or community nutrition professionals is vital to not only studying and understanding the interplay between economics, food policy, and health, but also to improving the ability to intervene and prevent many problems related to food insecurity in developed and developing countries. The purpose of this review is to outline and describe these issues as a means to open discussion on how to best alleviate major nutrition problems in the world
Research priorities in pediatric parenteral nutrition: a consensus and perspective from ESPGHAN/ESPEN/ESPR/CSPEN
We acknowledge all the authors of the ESPGHAN/ESPR/ESPEN/CSPEN pediatric
parenteral nutrition guidelines for their contributions and vote (Christian Braegger,
University Childrenās Hospital, Zurich, Switzerland; Jiri Bronsky, University Hospital
Motol, Prague, Czech Republic; Cristina Campoy, Department of Paediatrics, School of
Medicine, University of Granada, Granada, Spain; Magnus Domellof, Department of
Clinical Sciences, Pediatrics, UmeƄ University, Sweden; Nicholas Embleton, Newcastle
University, Newcastle upon Tyne, UK; Mary Fewtrell, UCL Great Ormond Street
Institute of Child Health, London, UK; Natasa Fidler, University Medical Centre
Ljubljana, Ljubljana, Slovenia; Axel Franz, University Childrenās Hospital, Tuebingen,
Germany; Oliver Goulet, University Sordonne-Paris-Cite; Paris-Descartes Medical
School, Paris, France; Corina Hartmann, Schneider Childrenās Medical Center of Israel,
Petach Tikva, Israel and Carmel Medical Center, Israel; Susan Hill, Great Ormond Street
Hospital for Children, NHS Foundation Trust and UCL Institute of Child Health,
London, UK; Iva Hojsak, Childrenās Hospital Zagreb, University of Zagreb School of
Medicine, University of J. J. Strossmayer School of Medicine Osijek, Croatia; Sylvia
Iacobelli, CHU La Reunion, Saint Pierre, France; Frank Jochum, Ev. Waldkrankenhaus
Spandau, Berlin, Germany; Koen Joosten, Department of Pediatrics and Pediatric
Surgery, Intensive Care, Erasmus MC Sophia Childrenās Hospital, Rotterdam, The
Netherlands; Sanja Kolacek, Childrenās Hospital, University of Zagreb School of
Medicine, Zagreb, Croatia; Alexandre Lapillone, Paris-Descartes University, Paris,
France; Szimonetta Lohner, Department of Pediatrics, University of Pecs, Pecs,
Hungary; Dieter Mesotten, KU Leuven, Leuven, Belgium; Walter Mihatsch, Ulm
University, Ulm, and Helios Hospital, Pforzheim, Germany; Francis Mimouni,
Department of Pediatrics, Division of Neonatology, The Wilf Childrenās Hospital, the
Shaare Zedek Medical Center, Jerusalem, and the Tel Aviv University, Tel Aviv, Israel;
Christian Molgaard, Department of Nutrition, Exercise and Sports, University of
Copenhagen, and Paediatric Nutrition Unit, Rigshospitalet, Copenhagen, Denmark;
Sissel Moltu, Oslo University Hospital, Oslo, Norway; Antonia Nomayo, Ev.
Waldkrankenhaus Spandau, Berlin, Germany; John Puntis, The General Infirmary at
Leeds, Leeds, UK; Arieh Riskin, Bnai Zion Medical Center, Rappaport Faculty of
Medicine, Technion, Haifa, Israel; Miguel Saenz de Pipaon, Department of
Neonatology, La Paz University Hospital, Red de Salud Materno Infantil y Desarrollo
e SAMID, Universidad Autonoma de Madrid, Madrid, Spain; Raanan Shamir, Schneider
Childrenās Medical Center of Israel, Petach Tikva, Israel; Tel Aviv University, Tel Aviv,
Israel; Peter Szitanyi, General University Hospital, First Faculty of Medicine, Charles
University in Prague, Czech Republic; Merit Tabbers, Emma Childrenās Hospital,
Amsterdam UMC, Amsterdam, The Netherlands; Chris van den Akker, Emma
Childrenās Hospital, Amsterdam UMC, Amsterdam, The Netherlands; Hans van
Goudoever, Emma Childrenās Hospital, Amsterdam UMC, Amsterdam, The Netherlands;
Sacha Verbruggen, Department of Pediatrics and Pediatric Surgery, Intensive
Care, Erasmus MC-Sophia Childrenās Hospital, Rotterdam, The Netherlands; Cai Wei,
Shanghai Jiao Tong University, Shanghai, China; Weihui Yan, Department of
Gastroenterology and Nutrition, Xinhua Hospital, School of Medicine, Shanghai Jiao
Tong University, Shanghai, China) and the members of the ESPR Section on Nutrition,
Gastroenterology and Metabolism (Fredrik Ahlsson, Uppsala University Childrenās
Hospital and Department of Womenās and Childrenās Health, Uppsala University,
Uppsala, Sweden; Sertac Arslanoglu, Division of Neonatology, Department of
Pediatrics, Istanbul Medeniyet University, Istanbul, Turkey; Wolfgang Bernhard,
Department of Neonatology, Childrenās Hospital, Faculty of Medicine, Eberhard-Karls-
University, TĆ¼bingen, Germany; Janet Berrington, Newcastle Neonatal Service,
Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK;
Signe Bruun, Hans Christian Andersen Hospital for Children and Adolescents, Odense
University Hospital, Odense, Denmark; Christoph Fusch, Department of Pediatrics, Paracelsus Medical School, General Hospital of Nuremberg, Nuremberg, Germany;
Shalabh Garg, South Tees Hospitals, Middlesborough, UK; Maria Gianni, Department
of Clinical Sciences and Community Health, University of Milan, Milan, Italy; Ann
Hellstrom, Institute of Neuroscience and Physiology, Sahlgrenska Academy at
University of Gothenburg, Gothenburg, Sweden; Claus Klingenberg, Department of
Pediatrics and Adolescence Medicine, University Hospital of North Norway, TromsĆø,
Norway; Helen Mactier, Neonatal Unit, Princess Royal Maternity Hospital, Glasgow,
UK; Neena Modi, Section of Neonatal Medicine, Department of Medicine, Chelsea and
Westminster Campus, Imperial College London, London, UK; Niels Rochow, Division
of Neonatology, Department of Pediatrics, McMaster University, Hamilton, Ontario,
Canada; Paola Rogerro, Department of Clinical Sciences and Community Health,
University of Milan, Milan, Italy; Umberto Simeoni, Division of Pediatrics, CHUV &
University of Lausanne, Lausanne, Switzerland; Atul Singhal, Paediatric Nutrition, UCL
Great Ormond Street Institute of Child Health, London, UK.; Ulrich Thome,
Department of Neonatology, Universitatsklinikum Leipzig, Leipzig, Germany; Anne
Twomey, Department of Neonatology, The National Maternity Hospital, Dublin,
Ireland; Mireille Vanpee, Karolinska University Hospital, Stockholm, Sweden; Gitte
Zachariassen, Hans Christian Andersen Hospital for Children and Adolescents,
Odense University Hospital, Odense, Denmark) for their vote.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
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 1ā4 and 14ā18 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 < ā2. One-third had %IVSE/REE > 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
- ā¦