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The insulator–metal transition in liquid hydrogen is an important phenomenon to understand the interiors of gas giants, such as Jupiter and Saturn, as well as the physical and chemical behavior of materials at high pressures and temperatures. Here, the path toward an experimental approach is detailed based on spectrally resolved x-ray scattering, tailored to observe and characterize hydrogen metallization in dynamically compressed hydrocarbons in the regime of carbon–hydrogen phase separation. With the help of time-dependent density functional theory calculations and scattering spectra from undriven carbon samples collected at the European x-ray Free-Electron Laser Facility (EuXFEL), we demonstrate sufficient data quality for observing C–H demixing and investigating the presence of liquid metallic hydrogen in future experiments using the reprated drive laser systems at EuXFEL.

We report fabrication, assembly and testing of the first >100 Gb/s monolithic electronic-photonic coherent receiver chip and sub-assembly, edge coupled to standard single mode fiber array.

Journal of physics / D 56(2), 025301 (2022). doi:10.1088/1361-6463/ac99e8, Published by IOP Publ., Bristol

The present work focuses on the application of electrophoretic deposition (EPD) as a facile process to generate homogeneous layers of multi walled carbon nanotubes (MWCNTs) using water as an environmentally friendly solvent. The EPD process requires a pretreatment of the commercially available MWCNT powder to create a surface charge on the surfaces of the MWCNTs as well as to realize stable suspensions. After pre-treatment, the electrophoretic mobility of the MWCNTs was approximately m ≈ − 4.3 · 10−4 cm2 V−1 s−1 and the resulting z-potential is in the range of z ≈ −55 mV. The suspension showed no sedimentation over 50 days. The EPD was carried out at an applied voltage of 50 V. The MWCNTs were successfully deposited as open porous layers on gold as well as on aluminum. The specific double layer capacitance of the MWCNT-layers on gold amounts to C ≈ 11.9 Fg−1. However, on aluminum as substrate, the EPD of the MWCNTs is associated with the formation of a thin barrier like oxide film. In this case a major part of the applied voltage drops down across the oxide film and only a minor part across the suspension. Consequently, the field strength in the suspension decreases. Moreover, the capacitance of the oxide film dominates the whole capacitance of the electrode. The specific capacitance amounts to C = 0.3 mFg−1 related to the deposited mass of MWCNTs.

We present results from the SPring-8 Angstrom Compact free electron LAser (SACLA) XFEL facility, using a high intensity ($\sim\!10^{20}\,$W/cm$^2$) X-ray pump X-ray probe scheme to observe changes in the ionic structure of silicon induced by X-ray heating of the electrons. By avoiding Laue spots in the scattering signal from a single crystalline sample, we observe a rapid rise in diffuse scattering, which we attribute to a loss of lattice order and a transition to a liquid state within 100 fs of irradiation, a timescale which agrees well with first principles simulations, but is faster than that predicted by purely inertial behavior. This method is capable of observing liquid scattering without masking or filtering of signal from the ambient solid, allowing the liquid structure to be measured throughout and beyond the phase change., 6 pages, 5 figures. Updated title and abstract

Physical review / B covering condensed matter and materials physics 101(5), 054301 (2020). doi:10.1103/PhysRevB.101.054301, We present measurements of the nucleation rate into a diamond lattice in dynamically compressed polystyrene obtained in a pump-probe experiment using a high-energy laser system and in situ femtosecond x-ray diffraction. Different temperature-pressure conditions that occur in planetary interiors were probed. For a single shock reaching 70 GPa and 3000 K no diamond formation was observed, while with a double shock driving polystyrene to pressures around 150 GPa and temperatures around 5000 K nucleation rates between 10(29) and 10(34) m(-3) s(-1) were recorded. These nucleation rates do not agree with predictions of the state-of-the-art theoretical models for carbon-hydrogen mixtures by many orders of magnitude. Our data suggest that there is significant diamond formation to be expected inside icy giant planets like Neptune and Uranus., Published by Inst., Woodbury, NY

Journal of Instrumentation 15(11), P11033 (2020). doi:10.1088/1748-0221/15/11/P11033, The von Hámos spectrometer setup at the HED instrument of the European XFEL is described in detail. The spectrometer is designed to be operated primarily between 5 and 15 keV to complement the operating photon energy range of the HED instrument. Four Highly Annealed Pyrolitic Graphite (HAPG) crystals are characterised with thicknesses of 40 μm or 100 μm and radius-of-curvature 50 mm or 80 mm, in conjunction with either an ePix100 or Jungfrau detector. The achieved resolution with the 50 mm crystals, operated between 6.5 and 9 keV, matches that reported previously: ~8 eV for a thickness of 40 μm, whereas, with an 80 mm crystal of thickness 40 μm, the resolution exceeds that expected. Namely, a resolution of 2 eV is demonstrated between 5–6 keV implying a resolving power of 2800. Therefore, we posit that flatter HAPG crystals, with their high reflectivity and improved resolving power, are a powerful tool for hard x-ray scattering and emission experiments allowing unprecedented measurements of collective scattering in a single shot., Published by Inst. of Physics, London

International audience; We present a proof-of-principle study demonstrating x-ray Raman Spectroscopy (XRS) from carbon samples at ambient conditions in conjunction with other common diagnostics to study warm dense matter, performed at the high energy density scientific instrument of the European x-ray Free Electron Laser (European XFEL). We obtain sufficient spectral resolution to identify the local structure and chemical bonding of diamond and graphite samples, using highly annealed pyrolytic graphite spectrometers. Due to the high crystal reflectivity and XFEL brightness, we obtain signal strengths that will enable accurate XRS measurements in upcoming pump-probe experiments with a high repetition-rate, where the samples will be pumped with high-power lasers. Molecular dynamics simulations based on density functional theory together with XRS simulations demonstrate the potential of this technique and show predictions for high-energy-density conditions. Our setup allows simultaneous implementation of several different diagnostic methods to reduce ambiguities in the analysis of the experimental results, which, for warm dense matter, often relies on simplifying model assumptions. The promising capabilities demonstrated here provide unprecedented insights into chemical and structural dynamics in warm dense matter states of light elements, including conditions similar to the interiors of planets, low-mass stars, and other celestial bodies.

A focusing 1D grating coupler is designed to interface a transverse-magnetic mode between a single-mode fiber and a silicon photonic nanowire. A theoretical coupling loss of -4 dB at a wavelength of 1550 nm is obtained. The proposed design is fabricated in a full-featured electronic photonic integrated circuit technology (photonic BiCMOS) and characterized experimentally for different coupling angles. Measurements show a coupling loss of -4.6 dB at 1555 nm and -4.3 dB at 1570 nm. Further designs are proposed for future fabrication and experiments.

Hintergrund: Die Erste und die Zweite Anderungsverordnung zur Trinkwasserverordnung traten in den Jahren 2011 und 2012 in Kraft und brachten fur Betreiber von gewerblichen Grosanlagen, in der Regel Warmwasseranlagen in groseren Wohngebauden, und fur die Gesundheitsamter erhebliche Zusatzaufgaben mit sich. In dem Beitrag werden die Erfahrungen des Gesundheitsamtes in Frankfurt am Main mit diesen neuen Verordnungen geschildert. Mit der zweiten Anderungsverordnung ( TrinkwV 2001 (2012) ) entfielen einige der Neuerungen der Ersten Anderungsverordnung ( TrinkwV 2001 (2011) ), u. a. die ursprungliche Anzeigepflicht fur Grosanlagen, daruber hinaus wurde die jahrliche Untersuchungspflicht direkt auf eine Untersuchung alle 3 Jahre gestreckt und es waren nur noch Uberschreitungen des technischen Masnahmenwerts dem Gesundheitsamt mitzuteilen statt zuvor alle Befunde. Ergebnisse: Auf Grundlage der TrinkwV 2001 (2011) war zunachst ein hoher zusatzlicher Personalbedarf fur das Gesundheitsamt Frankfurt (13 resp. 21 Stellen) geschatzt worden, nach der TrinkwV 2001 (2012) konnen die Aufgaben nun von weniger als 2 Mitarbeitern erledigt werden. Als die Anzeigepflicht noch galt, wurden dem Amt 4 461 Grosanlagen angezeigt, seither wurden ihm weitere 477 bekannt. Von bislang 1 335 vorliegenden Erstuntersuchungen wiesen 794 (60%) eine Uberschreitung des technischen Masnahmenwerts auf, in 113 Liegenschaften war bei Werten >10 000/100 ml eine Nutzungseinschrankung erforderlich. Schlussfolgerungen: Durch den Wegfall der Anzeigepflicht und der Ubermittlungspflicht fur alle Befunde gestaltet sich die Bearbeitung der gemeldeten Befunde aus Grosanlagen schwierig. Eine Evaluation der Verordnung ist sachgerecht nicht moglich, da die Zahl der relevanten Grosanlagen nicht bekannt ist und es sich bei einer „Nichtmeldung“ um eine Anlage mit Unterschreitung des technischen Masnahmenwerts oder um eine nicht untersuchte Anlage handeln kann. Die hohe Zahl der Nutzungseinschrankungen ist ein Hinweis fur die Notwendigkeit, Grosanlagen zu untersuchen und ggf. zu sanieren.

ZusammenfassungDer zweite Teil der Haltungsempfehlungen beschäftigt sich mit der Gesundheitsvorsorge sowie den gesetzlichen Rahmenbedingungen für die Haltung von Schafen und Ziegen, den Transport und die Eingriffe an Schafen und Ziegen. Das vorgeschlagene Konzept der Gesundheitsvorsorge zielt auf die Entwicklung eines für jede Herde individuellen Gesundheitsplans ab, in dem neben der Abwehr von anzeige- und meldepflichtigen Krankheiten gerade auch die chronischen, sich langsam entwickelnden Erkrankungen und ein regelmäßiges Parasitenmonitoring Berücksichtigung finden. Dabei liegt der Schwerpunkt auf dem frühen Erkennen und der Prophylaxe von Erkrankungen. In diesem Zusammenhang wird auf den Umgang mit Lahmheiten, die Schur, Tierzukauf und Quarantäne sowie die Reinigung und Desinfektion in Schaf- und Ziegenherden intensiver eingegangen. Zum Transport von Tieren und zu Eingriffen bei Tieren liegen mit der Tierschutztransportverordnung und entsprechenden europäischen Regelungen detaillierte Vorschriften zu diesen Komplexen vor. Die gesetzlichen Bestimmungen und die praktische Durchführung werden übersichtlich dargestellt.

ZusammenfassungInfektiöse Klauenerkrankungen des Schafes sind unter den Aspekten des Tierschutzes, der Diagnose und der Behandlung problematisch. Neben den Einzeltiererkrankungen und Lahmheiten im Zusammenhang mit Allgemeinerkrankungen stellen insbesondere die auf Herdenbasis auftretenden infektiösen Klauenerkrankungen wie die Moderhinke den behandelnden Tierarzt aus mehreren Gründen vor Probleme. In dem Artikel werden die verschiedenen Klauenerkrankungen kurz dargestellt und Hinweise zum Vorgehen bei der Therapie infektiöser Klauenkrankheiten des Schafes, zur Auswahl der Behandlungsmethode und zum Einsatz von Medikamenten gegeben. Die verschiedenen Behandlungsmaßnahmen wie Klauenschnitt, Klauenbäder, lokale und systemische antibiotische Therapie sowie die prophylaktische Impfung werden beschrieben und unter Berücksichtigung internationaler Forschungsergebnisse diskutiert. Bei der Auswahl der Medikamente zeigt sich, dass aufgrund fehlender Zulassungen in Deutschland der behandelnde Tierarzt beinahe regelmäßig gezwungen ist, Arzneimittel umzuwidmen. Die Problematik der medikamentösen Versorgung der kleinen Wiederkäuer als „minor species“ wird verdeutlicht und mit dem Aufruf an die involvierten Stellen verbunden, an einer Verbesserung dieser für alle Seiten unbefriedigenden Situation mitzuarbeiten.

ZusammenfassungEine hohe Neugeborenensterblichkeit, Milchmangel und vereinzelte Todesfälle bei Mutterschafen führten zur Untersuchung einer Dorper-Schafherde in Süddeutschland. Als zugrunde liegende Ursachen wurden Abmagerung und eine hohe Belastung mit Trichostrongylus spp. trotz regelmäßiger anthelminthischer Behandlung identifiziert. Die weitere parasitologische Untersuchung der Herde mittels Eizahlreduktionstest ergab keinerlei Eizahlreduktion nach Anwendung von Ivermectin oder Albendazol sowie eine deutlich verminderte Eizahlreduktion von 57,9% nach Behandlung mit Levamisol. Diese Ergebnisse sind Zeichen einer fehlenden bzw. deutlich verringerten Wirksamkeit von Stoffen aus allen drei klassischen Anthelminthikagruppen. Dieser Fall zeigt, dass auch in Deutschland mit Mehrfachresistenzen gegen die klassischen Anthelminthikagruppen gerechnet werden muss. Einschleppung resistenter Wurmpopulationen durch Zuchttierimporte, übermäßiger Einsatz von Anthelminthika und Unterdosierung von Wirkstoffen bei Ziegen stellen mögliche Ursachen im beschriebenen Fall dar und verdeutlichen, dass dem Parasitenmanagement und der Beratung von Schaf- und Ziegenhaltern von tierärztlicher Seite erhöhtes Augenmerk zu schenken ist.

ZusammenfassungEs werden Empfehlungen für die verschiedenen Haltungsformen auf der Basis der gesetzlichen Rahmenbedingungen für die Haltung von Schafen und Ziegen zusammengefasst. Berücksichtigung finden dabei die Wanderschäferei, die Hüte- und Koppelschafhaltung sowie die Alpung. Intensiv wird auf die Belange der Weidehaltung, der Stallhaltung, der Versorgung mit Futter und Wasser, der Geburt, der Lämmeraufzucht und der Gesundheitsvorsorge eingegangen. Dabei werden die Rahmenbedingungen sowohl für die extensive als auch für die intensive Haltung und Nutzung von Schafen und Ziegen abgesteckt. Die speziesspezifischen Kompensationsmöglichkeiten, deren Grenzen und Anzeichen der Dekompensation werden exemplarisch aufgezeigt. Durch die Einhaltung dieser Empfehlungen sollen den in unserer Obhut gehaltenen Nutztieren die „fünf Freiheiten (13)” zuverlässig gewährt werden: 1. Freisein von Hunger und Durst, 2. Freisein von Unbehagen, 3. Freisein von Schmerz, Verletzungen und Krankheiten, 4. Freisein zum Ausleben normaler Verhaltensweisen und 5. Freisein von Angst und Leiden.

Schulen sind verpflichtet, innerbetriebliche Verfahrensweisen zur Einhaltung der Hygiene in Hygieneplanen festzuschreiben. Sie unterliegen – wie auch Krankenhauser – der infektionshygienischen Uberwachung der Gesundheitsamter (§ 36 Infektionsschutzgesetz, IfSG). Die Umsetzung dieser Vorgaben des Infektionsschutzgesetzes werden in diesem Beitrag am Beispiel der Stadt Frankfurt am Main vorgestellt. Obwohl alle Schulen uber ihre Pflichten nach IfSG informiert worden waren und ihnen ein Musterhygieneplan zur Verfugung gestellt worden war, konnten bei einer Umfrage im Jahre 2006 nur 80 von 180 Schulen (44%) tatsachlich einen Hygieneplan vorweisen. Beschwerden uber mangelnde Sanitarhygiene konnen vom Gesundheitsamt oft bestatigt werden, allerdings durchaus auch in gerade aufwandig sanierten Sanitaranlagen, bedingt durch Vandalismus in den Schulen. Die Ausstattung von Waschbecken konnte im Zusammenhang mit der offentlichen Aufmerksamkeit im Rahmen der Influenzapandemie sehr gut verbessert werden, allerdings war ein Jahr spater wieder eine Tendenz zum Schlechteren erkennbar. Nach Untersuchungsbefunden mit hohen Feinstaub- und Kohlendioxidbelastungen in Klassenraumen wurde die Reinigungsfrequenz in den Klassenraumen wieder auf taglich erhoht (Verhaltnispravention) und eine Luftungsinitiative gestartet (Verhaltenspravention). Eine Untersuchung in 26 Schulen zeigte jedoch, dass nach wie vor zu wenig geluftet wird und die Kinder in der Regel sehr hohen CO2-Konzentrationen ausgesetzt sind. Umfangreiche Untersuchungen nach der Trinkwasserverordnung 2001 bestatigten eine gute hygienische Qualitat des Trinkwassers. Eine Ausnahme sind teilweise hohe Legionellenkontaminationen im Warmwassersystem von Schulturnhallen, die Desinfektions- und Sanierungsmasnahmen erforderlich machen. Der offentliche Gesundheitsdienst sollte seine gesetzliche Aufgabe der infektionshygienischen Beratung und Uberwachung der Schulen und Kindereinrichtungen ernst nehmen und gemeinsam mit den Schulgemeinden nach Losungswegen fur eine gute Hygiene in Schulen suchen. Auch die Eigenverantwortung der Schulnutzer ist gefragt, im Sinne der Verhaltnis – und der Verhaltenspravention. Mehr offentliche Aufmerksamkeit konnte ein Weg sein, vielleicht in Form der „Hygiene-Ampel fur Schulen“?

The Mucoromycotina unifies two heterogenous orders of the sporangiferous, soilinhabiting fungi. The Mucorales comprise saprobic, occasionally facultatively mycoparasitic, taxa bearing a columella, whereas the Mortierellales encompass mainly saprobic fungi lacking a columella. Multi-locus phylogenetic analyses based on eight nuclear genes encoding 18S and 28S rRNA, actin, alpha and beta tubulin, translation elongation factor 1alpha, and RNA polymerase II subunits 1 and 2 provide strong support for separation of the Mortierellales from the Mucoromycotina. The existence of a columella is shown to serve as a synapomorphic morphological trait unique to Mucorales, supporting the taxonomic separation of the acolumellate Mortierellales from the columellate Mucoromycotina. Furthermore, irregular hyphal septation and development of subbasally vesiculate sporangiophores bearing single terminal sporangia strongly correlate with the phylogenetic delimitation of Mortierellales, supporting a new subphylum, mortierellomycotina.

Background: This article investigated the prevalence of peanut allergy in three cohorts of children born in the same geographical location, Isle of Wight, UK and seeks to determine whether the prevalence of peanut allergy has changed between 1994 and 2004. Methods: Three cohorts of children (age 3-4 years) born on the Isle of Wight, were assessed for peanut allergy and the outcomes compared: Cohort A: Born in 1989; reviewed at 4 years of age (n = 2181). Cohort B: Born between 1994 and 1996; reviewed between 3 and 4 years of age (n = 1273). Cohort C: Born between 2001 and 2002; reviewed at 3 years of age (n = 891). Results: Peanut sensitization increased significantly from 1.3% in Cohort A to 3.3% (P = 0.003) in Cohort B before falling back to 2.0% in Cohort C (P = 0.145). Similarly, clinical peanut allergy increased significantly from 0.5% in Cohort A to 1.4% (P = 0.023) in Cohort B, with a subsequent fall to 1.2% in Cohort C (P = 0.850). Conclusions: Our data from three cohorts of 3- to 4-year-old children born in the same geographical area shows that peanut allergy prevalence has changed over time. Peanut sensitization and reported allergy in children born in 1994-1996 increased from 1989 but seems to have stabilized or slightly decreased since the late 1990s, although not significant.

Within the order Mucorales (Zygomycetes), the facultative parasites Parasitella parasitica, Chaetocladium brefeldii, Chaetocladium jonesii and Absidia parricida are known to initiate biotrophic fusion parasitic interactions on a wide variety of other mucoralean hosts. Their phylogenetic relationship within the Mucorales and their ability to form parasitic structures with several known host species was examined. Together with interspecific reactions between the mycoparasites, this study found: (i) no evident differences in the spectrum of non-parasitic hosts tested within the study; (ii) A. parricida parasitises all other fusion parasites; (iii) A. parricida is ancestral to all other parasites; (iv) A. parricida is reported for the first time as phylogenetically basal to all other mucoralean fungi except the Umbelopsidaceae and (v) based on phylogenetic analyses and physiological and morphological characteristics, the slow-growing species A. parricida and Absidia zychae are removed from the genus Absidia and reclassified in the newly described genus Lentamyces.

Background Blood–brain barrier (BBB) breakdown is an early event in the pathogenesis of multiple sclerosis (MS). In a previous study we have found a direct stabilization of barrier characteristics after treatment of bovine brain capillary endothelial cells (BCECs) with human recombinant interferon-β-1a (IFN-β-1a) in an in vitro BBB model. In the present study we examined the effect of human recombinant IFN-β-1a on the barrier properties of BCECs derived from four different species including humans to predict treatment efficacy of IFN-β-1a in MS patients. Methods We used primary bovine and porcine BCECs, as well as human and murine BCEC cell lines. We investigated the influence of human recombinant IFN-β-1a on the paracellular permeability for 3H-inulin and 14C-sucrose across monolayers of bovine, human, and murine BCECs. In addition, the transendothelial electrical resistance (TEER) was determined in in vitro systems applying porcine and murine BCECS. Results We found a stabilizing effect on the barrier characteristics of BCECs after pretreatment with IFN-β-1a in all applied in vitro models: addition of IFN-β-1a resulted in a significant decrease of the paracellular permeability across monolayers of human, bovine, and murine BCECs. Furthermore, the TEER was significantly increased after pretreatment of porcine and murine BCECs with IFN-β-1a. Conclusion Our data suggest that BBB stabilization by IFN-β-1a may contribute to its beneficial effects in the treatment of MS. A human in vitro BBB model might be useful as bioassay for testing the treatment efficacy of drugs in MS.

Four horses were randomly fed a diet containing rolled, micronised or extruded barley; the barley intake was adjusted to supply 2 g starch/kg bodyweight per day. During a 10-day acclimatisation period the horses were also fed 1 kg grass hay/100 kg bodyweight per day. Samples of blood and breath were collected at the end of each period after the test meal of barley had been fed after a 12-hour overnight fast. The glycaemic and insulinaemic responses of the horses were measured as an indication of the pre-caecal digestibility of starch, and postprandial breath hydrogen and methane were measured to detect microbial fermentation of starch. The highest peak serum glucose and serum insulin concentrations were observed after feeding the extruded barley, lower concentrations were observed after feeding the micronised barley and the lowest concentrations were observed after feeding the rolled barley. Breath hydrogen increased within four hours of feeding all the barley diets, and the mean (sd) peak hydrogen concentrations were 98.3 (55.2) ppm for rolled barley, 59.3 (31.5) ppm for micronised barley and 96.1 (51.9) ppm for extruded barley. There were wide variations within individual horses but these concentrations were not significantly different. Breath methane concentrations were very variable and, although there were no significant differences, there was a trend for higher methane concentrations after the feeding of rolled barley.

This work highlights the significance of immunomodulating drugs in the therapy for multiple sclerosis (MS) under health technology assessment aspects and current German, British and American treatment guidelines. Concerning MS therapy the following aspects were analysed: if the efficacy of the various immunomodulating drugs is similar, which cost-benefit relations occur and how implementation in national guidelines was realised. The different therapeutic options, either with beta-interferons or glatirameracetate, show nearly the same effects, an aspect which is also reflected by the national guidelines (Germany, United Kingdom and USA). The costs for the MS therapy are high, which caused the National Institute for Clinical Excellence not to recommend this therapy despite its efficacy. However, a compromise was found to satisfy the needs of patients, the government and the pharmaceutical industry in order to realise treatment of the disease. This shows the importance of evidence-based medicine, health technology assessment and guidelines as well as a possible and necessary flexibility to achieve a good medical service to patients with MS.

Background: Prevalence and incidence of food hypersensitivity (FHS) and its trends in early childhood are unclear. Methods: A birth cohort born on the Isle of Wight (UK) between 2001 and 2002 was followed-up prospectively. Children were clinically examined and skin prick tested at set times and invited for food challenges when indicated. Results: Nine hundred and sixty-nine children were recruited and 92.9%, 88.5% and 91.9% of them respectively were assessed at 1, 2 and 3 years of age. Prevalence of sensitization to foods was 2.2%, 3.8% and 4.5% respectively at these ages. Cumulatively, 5.3% [95% confidence interval (CI): 3.9-7.1] children were sensitized to a food. Using open food challenge and a good clinical history, the cumulative incidence of FHS was 6.0% (58/969, 95% CI: 4.6-7.7). Based on double-blinded, placebo-controlled, food challenge (DBPCFC) and a good clinical history, the cumulative incidence was 5.0% (48/969, 95% CI: 3.7-6.5). There is no evidence to suggest that the incidence of FHS has increased, comparing these results with previous studies. Overall, 33.7% of parents reported a food-related problem and of these, 16.1% were diagnosed with FHS by open challenge and history and 12.9% by DBPCFC and history. Main foods implicated were milk, egg and peanut. Conclusions: By the age of 3 years, 5-6% of children suffer from FHS based on food challenges and a good clinical history. There were large discrepancies between reported and diagnosed FHS. Comparing our data with a study performed in the USA more than 20 years ago, there were no significant differences in the cumulative incidence of FHS.

Background Correct diagnosis of food hypersensitivity (FHS) is important to ensure appropriate patient care and to accurately establish the population prevalence and incidence. Food challenges play a very important role in the diagnosis of FHS, but it is unclear when open food challenges (OFCs) opposed to double-blind placebo-controlled food challenges (DBPCFCs) should be used. This study investigated the use of OFCs and DBPCFCs when diagnosing FHS. Methods Children with a reported history of FHS or with sensitization to a food without known previous consumption were invited to undergo food challenges. Children of consenting parents underwent an OFC and those with a positive OFC were approached to undergo a DBPCFC. Food challenges were either performed as 1-day or 1-week challenges depending on sensitization status and clinical history. Results Forty-one children underwent both OFCs and DBPCFCs. The positive predictive values for 1-day and 1-week OFCs were 73% (8/11; 95% CI: 39–94%) and 57% (20/35; 95% CI: 39–74%) respectively. There was no evidence to indicate that the younger children were more likely to have a positive OFC confirmed by a DBPCFC compared to older children (Fisher’s exact P = 0.53). In the 1-day challenges parents indicated a preference for OFC rather than DBPCFC. By contrast, in the 1-week challenge parents indicated a preference for DBPCFC (P = 0.0192). Conclusion Open food challenge may be suitable for diagnosing immediate objective symptoms, whereas DBPCFC may be needed for the diagnosis of delayed and mainly subjective symptoms, irrespective of the child’s age.

For the flow around a circular cylinder, the steady flow changes its topology at a Reynolds number around 6 where the flow separates and a symmetric double separation zone is created. At the bifurcation point, the flow topology is locally degenerate, and by a bifurcation analysis we find all possible streamline patterns which can occur as perturbations of this flow. We show that there is no a priori topological limitation from further assuming that the flow fulfils the steady Navier–Stokes equations or from assuming that a Hopf bifurcation occurs close to the degenerate flow.The steady flow around a circular cylinder experiences a Hopf bifurcation for a Reynolds number about 45–49. Assuming that this Reynolds number is so close to the value where the steady separation occurs that the flow here can be considered a perturbation of the degenerate flow, the topological bifurcation diagram will contain all possible instantaneous streamline patterns in the periodic regime right after the Hopf bifurcation. On the basis of the spatial and temporal symmetry associated with the circular cylinder and the structure of the topological bifurcation diagram, two periodic scenarios of instantaneous streamline patterns are conjectured. We confirm numerically the existence of these scenarios, and find that the first scenario exists only in a narrow range after the Hopf bifurcation whereas the second one persists through the entire range of Re where the flow can be considered two-dimensional. Our results corroborate previous experimental and computational results.

The first and second amendment to the Drinking Water Ordinance came in to force in the years 2011 and 2012 causing additional tasks and responsibilities for operators of commercial large-scale systems, usually hot water systems in large residential buildings, and for the local health authorities. This article describes the experiences of the health authority in Frankfurt/Main with these new regulations. Some of the revisions in the first amendment of the ordinance (TrinkwV 2001 (2011)) were omitted in the second revision (TrinkwV 2001 (2012)) such as the obligation to notify for large-scale systems. Furthermore, the intervals between the obligatory inspections were extended from 1 to 3 years and merely exceedances of the legal limits were to be notified in contrast to the previous obligation to notify all values.On the basis of the TrinkwV 2001 (2011) a large additional staff requirement had been estimated (13/21 positions). After the TrinkwV 2001 (2012) the tasks can be accomplished by less than 2 employees. While the notification obligation was still in force, the health authority received 4,461 notifications of large-scale systems, since then a further 477 have been notified. Of a total of 1,335 initial analyses, 794 (60%) exceeded the technical action value and in 113 properties with values exceeding 10,000/100 ml a usage restriction was necessary.Due to the suspension of the notification obligation to report any result of the analyses performed the assessment of the reports on large-scale systems has become difficult. An appropriate assessment of the implementation of the regulation is not possible, since the total number of large-scale systems is not known and a failure to report may result from a measured value below the technical action value as well as from a not inspected system. The large number of usage restrictions is an indication for the necessity to inspect and if required to treat and restore the system.

The creation of recirculation bubbles in a steady, viscous flow in a cylindrical cavity with co-rotating top and bottom is investigated numerically. By varying the Reynolds number and the aspect ratio of the cylinder various axial-symmetric flow regimes are studied. It is observed that the topology of re-circulating vortex structures is associated with a change in helical symmetry of the vortex lines. The computations show that symmetry changes take place at increasing Reynolds numbers and that flow reversal on the center axis is associated with a growth of the twist parameter of the vortex lines. For all studied flow cases, independent of aspect ratio and Reynolds number, it was observed that the twist parameter of the central vortex attains a threshold value of K ≅ 0.6 at the point where flow reversal takes place.

The remediation of heavy metal-polluted aquatic sediment by solid-bed bioleaching requires a material well permeable to air and water. Freshly dredged sediment is nearly impermeable and needs previous conditioning to make it suitable for solid-bed leaching. This conditioning – in practice carried out by planting sediment packages with helophytes – comprises water removal by evapotranspiration, abiotic and microbial oxidation of sediment-borne reduced compounds, acidification, as well as structural changes improving the sediment permeability. The rate of this process seems to be limited by the transport of oxygen into the sediment bed. For a better understanding of the physicochemical processes occurring during conditioning, sediment oxidation was studied in a stirred suspension to minimize transport limitations. Freshly dredged, silty, anoxic, heavy metal-polluted sediment from the Weisse Elster River (Germany) was suspended in water and then continuously stirred and aerated at 20 °C. Aerobic conditions appeared within a few hours. The redox potential increased from – 400 to + 220 mV, at first very quickly and later more slowly. Sediment-borne inorganic sulfur compounds were oxidized to sulfate (S0 mainly within two days and sulfide within ten days), which reduced the pH from 7.2 to 5.9. A successive oxidation of FeS to Fe(II) sulfate, the oxidation of Fe(II) to Fe(III) followed by Fe(III) oxyhydrate formation caused the dissolved Fe to sharply increase and thereafter rapidly decrease. Ammonium was completely oxidized in a nitrification process to form nitrate, further decreasing the pH to 5.5. The acidification increased the solubility of Mn, Zn, Mg, Ca, and K. The increase in dissolved Mn rules out any oxidation of Mn(II) to Mn(IV) since Mn(IV) would have been insoluble under the prevailing pH and redox conditions. Sediment oxidation did not proceed in a well-defined, redox-potential-directed order, but individual (partly microbially) oxidation processes superimposed each other. Physicochemical conditioning of suspended sediment was completed after 20 days while conditioning in a solid bed would require months or even years. These different rates result from transport limitations in the solid bed. Sediment conditioning in a solid bed could therefore possibly be accelerated by prior sediment aeration.

A new ECRH system is being constructed for ASDEX Upgrade with a total power of 4 MW, generated by four gyrotrons, and a pulse duration of 10 s. Particular features are the use of gyrotrons which can work at various frequencies in the range 104–140 GHz and correspondingly broad band transmission components. The transmission will be at normal air pressure, and at the torus we will have a tunable double disk vacuum window. A further aim is the installation of fast moveable mirrors for a feedback controlled localized power deposition.

Problem Good hygienic practice in hospitals and other medical institutions is mandatory to avoid or to minimise nosocomial infections. In Germany, official recommendations of the commission for hospital hygiene and infection control have been published as guidelines for hygiene management in hospitals as well as guidelines for control measures of the public health services who are obliged by law to control the hygienic situation in hospitals. In this paper the degree of implementation of these guidelines in the hospitals is studied in respect of the hygiene management in the operation theatre. Material and method The constructive and functional situation and the personal hygienic management were documented in 22 community and private hospitals in Frankfurt am Main, including 40 operation suites with 111 operation theatres. Data of the layout of the rooms were obtained by questionnaire and the hygienic management was observed by means of standardised checklists. Results Layout of rooms was not compatible with the recommendations of the Guidelines of 1990 and 2000 in many cases--especially with regard to the demand that doors to the operating theatres be closed. Automatic door closers were often either not available or defective. In some theatre areas correct hand disinfection while entering the suite was not possible for lack of disinfectant distributors at appropriate sites. Recommendations regarding surgical drapes and gowns were correctly observed in most cases, with the exception of changing gowns after having gone to the toilet room. Quite often, omission of hand disinfection after glove removal was observed. A discrepancy in hygienic procedures of nursing service and physicians was seen. In 40 % of the operation suites, powdered gloves were still in use. Though in all but one suite air conditioning systems were available, they were not correctly serviced in many cases. Cleaning and disinfection after single operations and at the end of the operating day were carried out correctly in most cases--except in operation theatres for ophthalmologic operations. Here too, manual preparation and disinfection/sterilisation of surgical instruments was common, and inappropriate use of sterilisers as well as the use of so-called "quick"-sterilisers. Conclusions The recommendations of the commission for hospital hygiene and infection prevention are generally accepted as guidelines, although the degree of translation into practice was often unsatisfactory.

The aim of this work is to explain the influence of the solvent molecules on silicon dissolution using several hydrofluoric acid containing organic electrolytes. The investigations focus on the morphology of the mesopores and macropores and the electrochemical valence of the overall reaction. Some basic properties of the electrolyte (polarity, tendency to form silicon oxide, and the H donor properties) were found to dominate the macropore formation in p-type silicon. For macropore formation the correct balance between the two main dissolution paths (direct silicon dissolution and dissolution via an anodic oxide) is very important. For mesopores in highly doped p- and n-type silicon the direct dissolution is dominant. The consequences of mixing organic and aqueous solutions are discussed.

Multiple anthelmintic resistance in small ruminant nematodes is widespread in some overseas and tropical countries but is a relatively new problem in Europe. A population of Trichostrongylus spp. 100% resistant to ivermectin and albendazole and partially resistant to levamisole was identified in a Dorper sheep flock in Southern Germany using a faecal egg count reduction test and larval cultures. This is the first reported case of triple anthelmintic resistance in small ruminant gastrointestinal nematodes in Germany.