T cells in atopic eye disease

Background: Chronic allergic eye diseases comprise a clinically heterogeneous group of disorders, including atopic blepharoconjunctivitis (ABC), giant papillary conjunctivitis (GPC), vernal keratoconjunctivitis and atopic keratoconjunctivitis (AKC). The latter two are the most serious conditions by far, since both can be accompanied by corneal inflammation and represent potentially blinding disorders. Treatment with conventional mast cell stabilisers is often unsatisfactory and therapy therefore frequently relies on topical corticosteroids. Although a cell mediated immune response is thought to be involved in these diseases, very little is known about the cellular interactions leading to the immunopathology. T cells have been subdivided on the basis of their lymphokine production profile in the murine system. Recent evidence suggests the existence of such T cell subsets in the human system. T lymphocytes producing Interleukin (IL-) 4 and IL- 5 but no or little IL-2 and IFNy are thought to play an important regulatory role in the immunopathology of other chronic allergic conditions, such as asthma, atopic dermatitis and eczema. Aim: This study was undertaken to investigate the general cellular infiltrate in clinically distinct chronic allergic eye diseases and in particular, to study the distribution of T cell infiltrates and their activation status in order to establish their possible involvement in the regulation of immune processes in chronic allergic eye disease. Methods: Phenotypic differences and similarities of leukocytes infiltrating the different groups of chronic allergic eye disease were investigated employing immunohistochemical staining techniques. Furthermore, the production of lymphokines by T cells was analyzed utilising in situ hybridisation histochemical techniques. The in situ analysis of lymphokine mRNA expression by these T cells was carried out using 35S-labelled riboprobes for IL-2, IL-3, IL-4 and IL-5. Results: Immunohistochemistry revealed a highly significant increase in the number of CD4 + memory (CD45-RO +) T cells in tarsal conjunctival biopsies obtained from patients with VKC and GPC (p<0.001) and a significant increase in tarsal biopsies obtained from patients with AKC (p<0.01). T cells were activated, expressing HLA-DR on their surface. In addition, macrophages and Langerhans cells were upregulated significantly in the conjunctiva of patients with VKC and GPC indicating their possible role in the presentation of antigen to T cells. In situ hybridisation histochemistry revealed a significantly greater number of biopsies from patients with VKC and GPC with signal for IL-3, IL-4 IL-5 and IL-4 mRNA respectively in T cell rich areas of tarsal conjunctiva than normal controls. Although lymphokine mRNA expression was not greater in AKC than normal conjunctiva, several tarsal biopsies from patients with AKC showed mRNA expression for all lymphokines studied. Conclusions: The prevalence of large numbers of CD4+ memory T cells in VKC, GPC and AKC suggested their active involvement in the regulation of the immune response in these chronic allergic eye conditions. Although CD4+ T cells were increased in all allergic patient groups, in situ hybridisation histochemistry revealed differences in lymphokine mRNA expression by T cells infiltrating AKC and VKC. T cells infiltrating VKC bore similarities to murine Th2, while T cells present in AKC revealed a broader spectrum of lymphokine mRNA expression. Therefore, it was put forward that patients with AKC and ABC may have contained T cell populations with a deregulated lymphokine production that led to an overexpression of IL-4 and IL-5 mRNA, while T cells present in VKC and GPC represented possibly normal, late memory T cells producing lymphokines similar to murine Th2

Reviewing model calculations of the Collins fragmentation function

The Collins fragmentation function describes a left/right asymmetry in the fragmentation of a transversely polarized quark into a hadron in a jet. Four different model calculations of the Collins function have been presented in the literature. While based on the same concepts, they lead to different results and in particular to different signs for the Collins function. The purpose of the present work is to review the features of these models and correct some errors made in previous calculations. A full study of the parameter dependence and the possible modifications to these models is beyond the scope of the paper. However, some general conclusions are drawn

Yellow laser performance of Dy3+^{3+} in co-doped Dy,Tb:LiLuF4_4

We present laser results obtained from a Dy$^{3+}$-Tb$^{3+}$ co-doped LiLuF$_{4}$ crystal, pumped by a blue emitting InGaN laser diode, aiming for the generation of a compact 578 nm source. We exploit the yellow Dy$^{3+}$ transition $^{4}$F$_{9/2}$ $\Longrightarrow$ $^{6}$H$_{13/2}$ to generate yellow laser emission. The lifetime of the lower laser level is quenched via energy transfer to co-doped Tb$^{3+}$ ions in the fluoride crystal. We report the growth technique, spectroscopic study and room temperature continuous wave (cw) laser results in a hemispherical cavity at 574 nm and with a highly reflective output coupler at 578 nm. A yellow laser at 578 nm is very relevant for metrological applications, in particular for pumping of the forbidden $^{1}$S$_{0} \Longrightarrow ^{3}$P$_{0}$ Ytterbium clock transition, which is recommended as a secondary representation of the second in the international system (SI) of units. This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.39.006628. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Comment: 8 pages, 5 figure

Solid-liquid equilibria of Sorel phases and Mg (OH)₂ in the system Na-Mg-Cl-OH-H₂O. Part I: experimental determination of OH⁻ and H⁺ equilibrium concentrations and solubility constants at 25°C, 40°C, and 60°C

Sorel phases are the binder phases of the magnesia building material (Sorel cement/concrete) and of special concern for the construction of long-term stable geotechnical barriers in repositories for radioactive waste in rock salt, as potentially occurring brines are expected to contain MgCl2. Sorel phases, in addition to Mg(OH)2, are equally important as pH buffers to minimize solubility and potential mobilization of radionuclides in brine systems. In order to obtain a detailed database of the relevant solid-liquid equilibria and the related pHm values of the equilibrium solutions, extensive experimental investigations were carried out. Solid phase formation was studied by suspending MgO and Mg(OH)2 in NaCl saturated MgCl2-solutions at 25°C. Mg(OH)2 and the 3-1-8 Sorel phase were identified as the stable solid phases, while the 5-1-8 Sorel phase is metastable. Equilibration at 40°C did not lead to any solid phase changes. Both OH− and H+ equilibrium concentrations were analyzed as a function of MgCl2 concentration at 25°C and 40°C. In addition to our already published solid-liquid equilibria for the ternary system Mg-Cl-OH-H2O (25°C–120°C), the equilibrium H+ concentrations (pHm) determined at 25°C, 40°C and 60°C are now reported. Analyzing these data together with known ion-interaction Pitzer coefficients, the solubility constants for Mg(OH)2 and the 3-1-8 phase at these three temperatures, for the metastable 5-1-8 phase at 25°C and for the 2-1-4 phase at 60°C have been consistently calculated

Psychische Belastung, Alkoholabhängigkeit und Rauchen

Die Prävalenz des Tabakkonsums ist bei Personen mit einer Neigung zur Depression höher als in der Allgemeinbevölkerung. Gleiches gilt für Personen mit einer Erkrankung aus dem schizophrenen Formenkreis. Alkoholabhängige Patienten weisen eine höhere psychische Belastung auf als nichtabhängige Personen. Bislang ungeklärt ist, inwiefern sich die rauchenden von den nichtrauchenden alkoholabhängigen Personen hinsichtlich ihrer psychischen Belastung unterscheiden. Es wurden Daten von 1403 Patienten mit der Hauptdiagnose „Alkoholabhängigkeit“ aus 40 Suchtrehabilitationskliniken zu Beginn der stationären Behandlung erhoben. 84% der Stichprobe sind Raucher. Die Messung der subjektiv empfundenen psychischen Symptombelastung erfolgte mittels der neun Skalen des Brief Symptom Inventory (BSI). Innerhalb der untersuchten Population der alkoholabhängigen Patienten weisen die zusätzlich rauchenden Patienten in den Bereichen Zwanghaftigkeit (T-Werte: 58 vs. 55), Depressivität (T-Werte: 64 vs. 61), Aggressivität (T-Werte: 59 vs. 55) und Psychotizismus (T-Werte: 63 vs. 59) signifikant höhere Werte auf als die Vergleichsgruppe. Diese Ergebnisse implizieren eine im Durchschnitt höhere Symptombelastung von rauchenden Alkoholpatienten im Vergleich zu nichtrauchenden Patienten. Dies impliziert eine klarere Diagnostik dieser Patientengruppe sowie das Bereitstellen von intensiveren Tabakentwöhnungsmaßnahmen für spezifische Subgruppen von Rauchern. Die Ergebnisse können als mögliche Erklärung herangezogen werden, weshalb diesen Patienten eine Aufgabe des Tabakkonsums besonders schwer fällt. Zu diskutieren bleibt die Richtung der Kausalität

Solid-liquid equilibria of Sorel phases and Mg (OH)2 in the system Na-Mg-Cl-OH-H2O. Part I: experimental determination of OH− and H+ equilibrium concentrations and solubility constants at 25°C, 40°C, and 60°C

Sorel phases are the binder phases of the magnesia building material (Sorel cement/concrete) and of special concern for the construction of long-term stable geotechnical barriers in repositories for radioactive waste in rock salt, as potentially occurring brines are expected to contain MgCl2. Sorel phases, in addition to Mg(OH)2, are equally important as pH buffers to minimize solubility and potential mobilization of radionuclides in brine systems. In order to obtain a detailed database of the relevant solid-liquid equilibria and the related pHm values of the equilibrium solutions, extensive experimental investigations were carried out. Solid phase formation was studied by suspending MgO and Mg(OH)2 in NaCl saturated MgCl2-solutions at 25°C. Mg(OH)2 and the 3-1-8 Sorel phase were identified as the stable solid phases, while the 5-1-8 Sorel phase is metastable. Equilibration at 40°C did not lead to any solid phase changes. Both OH− and H+ equilibrium concentrations were analyzed as a function of MgCl2 concentration at 25°C and 40°C. In addition to our already published solid-liquid equilibria for the ternary system Mg-Cl-OH-H2O (25°C–120°C), the equilibrium H+ concentrations (pHm) determined at 25°C, 40°C and 60°C are now reported. Analyzing these data together with known ion-interaction Pitzer coefficients, the solubility constants for Mg(OH)2 and the 3-1-8 phase at these three temperatures, for the metastable 5-1-8 phase at 25°C and for the 2-1-4 phase at 60°C have been consistently calculated

Outlining where humans live -- The World Settlement Footprint 2015

Human settlements are the cause and consequence of most environmental and societal changes on Earth; however, their location and extent is still under debate. We provide here a new 10m resolution (0.32 arc sec) global map of human settlements on Earth for the year 2015, namely the World Settlement Footprint 2015 (WSF2015). The raster dataset has been generated by means of an advanced classification system which, for the first time, jointly exploits open-and-free optical and radar satellite imagery. The WSF2015 has been validated against 900,000 samples labelled by crowdsourcing photointerpretation of very high resolution Google Earth imagery and outperforms all other similar existing layers; in particular, it considerably improves the detection of very small settlements in rural regions and better outlines scattered suburban areas. The dataset can be used at any scale of observation in support to all applications requiring detailed and accurate information on human presence (e.g., socioeconomic development, population distribution, risks assessment, etc.)

Teaching Tips – Gute Lehre ist kein Glücksfall!

Fragen wir die Teilnehmerinnen und Teilnehmer unserer hochschuldidaktischen Weiterbildungen nach ihren Erwartungen, so nennen sie an erster Stelle immer „konkrete Hilfestellungen für den Lehralltag“. Schauen wir genauer hin, wie diese Hilfestellungen aussehen könnten, so zeigen sich deutliche Unterschiede in den Zielgruppen der Lehrenden. Stehen sie noch am Anfang ihrer Lehrkarriere, wünschen sie sich besonders Hilfestellungen, die den Einstieg in die Lehre erleichtern bzw. ihnen helfen, effektiv zu lehren und effiziente Lehrende zu werden. Für erfahrene Lehrende hingegen, die zudem mit Prüfungen betraut sind, stellt sich darüber hinaus oft die Frage nach der Auswahl von Prüfungsformen und die Bewertung von Prüfungsleistungen, vor allem da ihnen die Modulabschlussprüfungen eine größere Bandbreite an Formen alternativer Leistungsbewertung eröffnen. Beiden Zielgruppen gemein ist die Suche nach praktischer Hilfe bei der Professionalisierung ihres didaktischen Handelns. Mit Patentrezepten ist ihnen dabei nicht gedient. Das Interesse der Lehrenden an Methoden wird gleichwohl als ein legitimes Interesse gesehen, denn Methodenwissen spielt bei der Vermittlung von Wissen eine große Rolle. Besonders im Kontext von Medialisierung werden die Vermittlungsmethoden wichtiger. Die hochschuldidaktische Weiterbildung will den Lehrenden bei der Entwicklung ihres individuellen und professionellen Lehrprofils theoretisch begründet, serviceorientiert zur Seite stehen. Seit Mitte der 1990er Jahre ist die didaktische Ausbildung für die Lehre nicht mehr dem Zufall überlassen, ebenso wie es keine Notwendigkeit mehr ist, sich hochschuldidaktisches Wissen autodidaktisch anzueignen. Die Entwicklung der Hochschuldidaktik und damit einhergehend die Entwicklung von curriculumbasierten, modularisierten und systematisch aufgebauten Weiterbildungsprogrammen hat in den letzten Jahrzehnten nicht zuletzt dank verschiedener Programme und Initiativen (z.B. Länderprogramme „Qualität der Lehre“, „Exzellenzinitiative“, BMBF, Stifterverband) eine enorme Steigerung erfahren. Die Qualität der Lehre an Universitäten ist zu einem Wettbewerbsfaktor unter den Universitäten geworden und kann zu ihrer Profilbildung beitragen. Die Lehrkompetenz kann als Schlüssel für die Qualität der Lehre gesehen werden und ist ein Merkmal akademischer Personalentwicklung. Dieses Journal soll in kleinem Rahmen als praxisorientierter Ratgeber auftreten. Es soll darüber hinaus das Interesse an hochschuldidaktischer Weiterbildung wecken, Lust machen, sich mit der eigenen Lehre auseinanderzusetzen, sich den kollegialen Fragen der anderen Teilnehmer/inne/n in den Workshops zu stellen, gemeinsam mit ihnen und uns, den Hochschuldidaktikern und Hochschuldidaktikerinnen, mögliche Antworten aufzuspüren und so das eigene Lehrrepertoire zu erweitern

World Settlement Footprint 3D - A first three-dimensional survey of the global building stock

Settlements, and in particular cities, are at the center of key future challenges related to global change and sustainable development. Widely used indicators to assess the efficiency and sustainability of settlement development are the compactness and density of the built-up area. However, at global scale, a temporally consistent and spatially detailed survey of the distribution and concentration of the building stock – meaning the total area and volume of buildings within a defined spatial unit or settlement, commonly referred to as building density – does not yet exist. To fill this data and knowledge gap, an approach was developed to map key characteristics of the world’s building stock in a so far unprecedented level of spatial detail for every single settlement on our planet. The resulting World Settlement Footprint 3D dataset quantifies the fraction, total area, average height, and total volume of buildings for a measuring grid with 90 m cell size. The World Settlement Footprint 3D is generated using a modified version of the World Settlement Footprint human settlements mask derived from Sentinel-1 and Sentinel-2 satellite imagery at 10 m spatial resolution, in combination with 12 m digital elevation data and radar imagery collected by the TanDEM-X mission. The underlying, automated processing framework includes three basic workflows: one estimating the mean building height based on an analysis of height differences along potential building edges, a second module determining the building fraction and total building area within each 90 m cell, and a third part combining the height information and building area in order to determine the average height and total built-up volume at 90 m gridding. Optionally, a simple 3D building model (level of detail 1) can be generated for regions where data on the building footprints is available. A comprehensive validation campaign based on 3D building models obtained for 19 regions (~86,000 km2) and street-view samples indicating the number of floors for >130,000 individual buildings in 15 additional cities documents that the novel World Settlement Footprint 3D data provides valuable and, for the first time, globally consistent information on key characteristics of the building stock in both, large urban agglomerations as well as small-scale rural settlements. Thus, the new dataset represents a promising baseline dataset for a wide range of previously impossible environmental, socioeconomic, and climatological studies worldwide