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In der rheumatologischen Praxis treten immer wieder Situationen auf, die eine umgehende Entscheidung des Rheumatologen erfordern, um bleibende Schäden vom Patienten abzuwenden. Insbesondere handelt es sich um fulminant verlaufende entzündliche Erkrankungen, schwere Nebenwirkungen durch zahlreiche Medikamente oder auch Infektionskomplikationen unter einer immunsuppressiven Therapie.

IMPORTANCE: Invasive physiologic indices such as fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are used in clinical practice. Nevertheless, comparative prognostic outcomes of iFR-guided and FFR-guided treatment in patients with type 2 diabetes have not yet been fully investigated. OBJECTIVE: To compare 1-year clinical outcomes of iFR-guided or FFR-guided treatment in patients with and without diabetes in the Functional Lesion Assessment of Intermediate Stenosis to Guide Revascularization (DEFINE-FLAIR) trial. DESIGN, SETTING, AND PARTICIPANTS: The DEFINE-FLAIR trial is a multicenter, international, randomized, double-blinded trial that randomly assigned 2492 patients in a 1:1 ratio to undergo either iFR-guided or FFR-guided coronary revascularization. Patients were eligible for trial inclusion if they had intermediate coronary artery disease (40%-70% diameter stenosis) in at least 1 native coronary artery. Data were analyzed between January 2014 and December 2015. INTERVENTIONS: According to the study protocol, iFR of 0.89 or less and FFR of 0.80 or less were used as criteria for revascularization. When iFR or FFR was higher than the prespecified threshold, revascularization was deferred. MAIN OUTCOMES AND MEASURES: The primary end point was major adverse cardiac events (MACE), defined as the composite of all-cause death, nonfatal myocardial infarction, or unplanned revascularization at 1 year. The incidence of MACE was compared according to the presence of diabetes in iFR-guided and FFR-guided groups. RESULTS: Among the total trial population (2492 patients), 758 patients (30.4%) had diabetes. Mean age of the patients was 66 years, 76% were men (1868 of 2465), and 80% of patients presented with stable angina (1983 of 2465). In the nondiabetes population (68.5%; 1707 patients), iFR guidance was associated with a significantly higher rate of deferral of revascularization than the FFR-guided group (56.5% [n = 477 of 844] vs 46.6% [n = 402 of 863]; P < .001). However, it was not different between the 2 groups in the diabetes population (42.1% [n = 161 of 382] vs 47.1% [n = 177 of 376]; P = .15). At 1 year, the diabetes population showed a significantly higher rate of MACE than the nondiabetes population (8.6% vs 5.6%; adjusted hazard ratio [HR], 1.88; 95% CI, 1.28-2.64; P < .001). However, there was no significant difference in MACE rates between iFR-guided and FFR-guided groups in both the diabetes (10.0% vs 7.2%; adjusted HR, 1.33; 95% CI, 0.78-2.25; P = .30) and nondiabetes population (4.7% vs 6.4%; HR, 0.83; 95% CI, 0.51-1.35; P = .45) (interaction P = .25). CONCLUSIONS AND RELEVANCE: The diabetes population showed significantly higher risk of MACE than the nondiabetes population, even with the iFR-guided or FFR-guided treatment. The iFR-guided and FFR-guided treatment showed comparable risk of MACE and provided equal safety in selecting revascularization target among patients with diabetes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02053038

Background Long-term risk factor control after myocardial infarction (MI) is currently inadequate and there is an unmet need for effective secondary prevention programmes.Design and methods It was the aim of the study to compare a 12-month intensive prevention programme (IPP), coordinated by prevention assistants and including education sessions, telephone visits and telemetric risk factor control, with usual care after MI. Three hundred and ten patients were randomized to IPP vs. usual care one month after hospital discharge for MI in two German heart centres. Primary study endpoint was the IPP Prevention Score (0–15 points) quantifying global risk factor control.Results Global risk factor control was strongly improved directly after MI before the beginning of the randomized study (30% increase IPP Prevention Score). During the 12-month course of the randomized trial the IPP Prevention Score was improved by a further 14.3% in the IPP group (p< 0.001), while it decreased by 11.8% in the usual care group (p< 0.001). IPP significantly reduced smoking, low-density lipoprotein cholesterol, systolic blood pressure and physical inactivity compared with usual care (p< 0.05). Step counters with online documentation were used by the majority of patients (80%). Quality of life was significantly improved by IPP (p< 0.05). The composite endpoint of adverse clinical events was slightly lower in the IPP group during 12 months (13.8% vs. 18.9%, p= 0.25).Conclusions A novel intensive prevention programme after MI, coordinated by prevention assistants and using personal teachings and telemetric strategies for 12 months, was significantly superior to usual care in providing sustainable risk factor control and better quality of life.

The correlation between ultraviolet radiation of the skin and melanoma incidence in humans is well established. Interestingly, epidemiologic data suggest also a correlation to an increased BMI pointing to metabolic trigger factors in melanoma pathogenesis. To substantiate this connection, we studied the expression of G-protein-coupled receptor 120 (GPR120), a receptor sensitive to unsaturated long-chain free fatty acids in melanoma tissues. One-hundred fourteen tissue sections histologically confirmed as nevi (n=32), primary melanoma (n=39), and melanoma metastasis (n=43) were immunohistochemically stained against GPR120. The staining was evaluated by three trained dermatopathologists and independently scored. Compared with nevi, primary melanoma and melanoma metastasis showed significantly higher levels of GPR120 staining. Only three out of 32 nevi showed strong GPR120 expression [median immunoreactivity-scoring system (IRS) score: 1, range: 0–10], whereas in primary melanomas 14 out of 39 were highly GPR120-positive (median IRS score: 7, range: 0–12) and in melanoma metastasis 27 out of 43 were highly GPR120-positive (median IRS score: 9, range: 0–12). GPR120 expression and tumor thickness (mm) show a statistically significant correlation in primary melanoma (P=0.011). Moreover, GPR120-positive staining was found throughout the epidermis and in sebaceous and sweat glands, which is yet not described. This study identified GPR120 as a novel marker for melanoma, indicating that melanoma cells are sensitive to free fatty acids. It is tempting to speculate that pharmacologically interfering with GPR120 signaling might improve melanoma therapy.

In einer Weltgesellschaft, die auf die Beschleunigung von Produktion, Verschleiß und Zerstörung abgestellt ist, erscheint das Museum als eine Heterotopie und -chronie. Indem es singuläre, anschauliche Gegenständlichkeiten bewahrt und als Exponate hic et nunc zugänglich macht, bildet es eine Enklave des Gedächtnisses inmitten einer generalisierten Amnesie und ermöglicht eine Form der Erhaltung, die auf andere Arten der Speicherung: Archivationen des Wissens, Datenbanken und ubiquitär abrufbare Informationen, unreduzierbar ist. Das Museum dekontextualisiert und reaktualisiert und eröffnet der Kunst den Ort ihres Daseins. Seine Möglichkeit ist in der Scheidung zwischen dem, was erhalten und vergessen werden soll, beschlossen, seine Raumzeit führt auf die Frage, ob und inwiefern auch das, was unsichtbar (geworden) ist, gezeigt werden kann.

We present direct experimental evidence that in GaxIn1-xAs/InP quantum wells the bandstructure undergoes a direct-to-indirect gap transition in k-space above a critical value of x. We observe a drastical increase of the measured radiative exciton lifetimes for samples where x>xc, with xc, depending on well width. Using a six-band k.p calculation of the valence subbands we show that for x>xcthe valence band maximum is at k ≠ 0, i.e. the bandstructure becomes indirect.

We performed differential transmission spectroscopy and time resolved pump probe measurements on biased InGaAs/InGaAsP multiple quantum well structures. At low carrier excitation levels we observe a shift in the energy of the excitonic absorption resonance caused by the photogenerated carriers screening the applied electric field within the quantum wells. Increasing the pump power the exciton transmission energy blue shifts until it reaches the zero internal field energy position. For our pump-probe measurements field screening dominates at pump powers lower than 50 W/cm2while at higher powers exciton saturation becomes dominant. We deduce a saturation intensity of 250 W/cm2.

The high speed steels ASP30 and ASP60 were rapidly quenched from the melt using the melt spinning method. Their structure was investigated in the as-quenched state as well as in-situ during annealing at 560 °C and 700 °C, respectively. The carbide precipitates were identified by wide angle X-ray diffraction. For the small angle X-ray scattering measurements (down to Qmin= 2 x 10-3Å-1) a laboratory-built pin hole instrument, equipped with a furnace and a 2-dimensional detector, was used. Slowly growing M6C-carbides are the dominant precipitates. Rapidly growing MC-carbides are present in ASP60 with a smaller fraction, but no M2C-carbides develop. The coarsening of the precipitates saturates at long annealing times. The Johnson-Mehl-Avrami analysis of the evolution of the volume fraction of M6C in ASP60 indicates a transition in the precipitation kinetics.

Die Datenlage bezüglich Sicherheit und Wirksamkeit verschiedener Biologika-Kombinationen ist noch nicht ausreichend untersucht, um dieses Thema abschließend eindeutig beurteilen zu können. Entsprechend der vorliegenden Daten bleibt daher die Biologika-Biologika-Kombination aufgrund einer eher geringen Wirksamkeit sowie teilweise deutlich höheren Infektionsrate enttäuschend und stellt nur in sehr speziellen Einzelfällen eine mögliche Option dar (RTX plus TNFi).Generell sollten Biologika-Kombinationen aktuell nur im Rahmen von klinischen Studien eingesetzt werden. Auch erscheint das Verhältnis von finanziellem Aufwand und Wirksamkeit einer Biologika-Kombination im Vergleich zum Wechsel auf heute zur Verfügung stehende Biologika (Anti-Zytokin-Prinzip, T-Zell-Aktivierung-Inhibition, B-Zell-Depletion) bzw. Wechsel der DMARD-Kombinationen sehr fraglich. Neue, die intrazellulären Signalwege beeinflussenden Medikamente („small molecules“) befinden sich in der Zulassung oder sind bereits in einigen Ländern zugelassen und verbessern das bestehende Armamentarium weiter. Auch werden Kombinationen mit den „small molecules“ in Zukunft möglicherweise eine spannende Entwicklung erfahren.Dieser Review gibt eine tabellarische Übersicht der vorliegenden Studien zur Kombination von Biologika.Data with respect to safety and therapeutic efficacy for the combination of biological DMARDs is scarce and inhomogeneous in order to make final conclusions. To this end, data to biologic combinations is disappointing due to relatively low therapeutic efficacy and partially enhanced rates of severe infectious events. Combining biologics is an option only in very special situations (RTX plus TNFi). In addition, the relation of financial effort to therapeutic efficacy is questionable, especially in the situation of numerous drug options (anti-cytokine principle, T-cell inhibition, B-cell depletion) and therapeutic strategies of combining biologics with DMARDs. Generally speaking, combinations of biological should only be used in clinical trials. New drugs influencing intracellular signaling pathways (small molecules) are going to be approved or are already approved by the drug agencies, thus, adding to the existing armamentarium. Furthermore, combinations with these new molecules are going to be interesting.This review summarizes the available studies concerning combination of biologicals in a tabular fashion.

Die klinischen Erscheinungsformen der Psoriasisarthritis (PsA) sind ausgesprochen vielfältig. Dies spiegelt sich in einer epidemiologisch heterogenen Datenlage bezüglich der Häufigkeit im Allgemeinen, der prädisponierten Altersgruppe sowie der Häufigkeit von Gelenk-, Wirbelsäulen-, Enthesen- und extraartikulären Manifestationen wider. Jedoch ist selbst für den Spezialisten die Differenzierung von PsA-Formen, anderen überlappenden oder klinisch ähnlich imponierenden Krankheitsbildern nicht immer eindeutig möglich. In diesem Beitrag sollen Anregungen und Hilfestellungen für eine sinnvolle und systematische Vorgehensweise zum Screening und zur Frühdiagnose einer PsA bei Patienten mit Psoriasis gegeben werden. Der Mainzer PsA-Screening- und -Frühdiagnostik-Algorithmus wird vorgestellt.

An essay is presented regarding the Haiku poems of Tomas Tranströmer. It mentions that Tranströmer was established as a promising new talent through the publications of "17 Dikter" in 1954 and "Secrets on the Way" in 1958. It says that the subconscious which was referred as a sort of hidden awareness of a reality underlying reality played a great part in his poetry.

Zusammenfassung: Interventionen an den Bewegungsorganen sind ein fester Bestandteil in der täglichen rheumatologischen Praxis und besitzen einen hohen Stellenwert bei der Diagnostik und Therapie entzündlicher und degenerativer Gelenkerkrankungen. So gehören konsequenterweise Gelenkpunktionen zum Inhalt der internistisch-rheumatologischen Weiterbildung. Ein Großteil der Punktionen wird auch heute noch „blind“, d. h. unter Zuhilfenahme anatomischer Leitstrukturen, durchgeführt. Allerdings konnte inzwischen durch zahlreiche Studien die ungenügende Präzision der nur klinisch gesteuerten Eingriffe belegt werden. Mit zunehmender Verbreitung der Arthrosonographie in der Rheumatologie hat sich diese als Methode der Wahl zur Steuerung von Eingriffen an Gelenken und Weichteilen etabliert. In dieser Übersichtsarbeit sollen die Indikationen und insbesondere die praktische Durchführung der für den Rheumatologen relevanten sonographisch gesteuerten Interventionen dargestellt werden.

Zusammenfassung: Die Verwendung von Ultraschall ist in der klinischen Praxis allgegenwärtig. Punktionen von Gewebestrukturen und Injektionen mit Lokalanästhetika sowie Glukokortikoiden werden in vielen Praxen regelmäßig praktiziert. Jedoch können Fehlpunktionen mit möglichen schwerwiegenden Nebenwirkungen wie Blutungen, Verletzung von delikaten Strukturen, glukokortikoidinduzierten Sehnenrupturen und Hautnekrosen vergesellschaftet sein. Aus diesen Gründen erscheint es wichtig, die Technik der ultraschallgesteuerten Punktion und Injektion ausführen zu können. Die Koordination von Auge, Schallkopf und Punktionshand muss jedoch vor der Anwendung am Menschen geübt werden. Wir beschreiben hier ein kostengünstiges, leicht herzustellendes und lerneffektives Punktionsmodell, um die Technik und Koordination der ultraschallgesteuerten Punktion sicher zu erlernen. Mit diesem Modell kann eine im Ultraschall ungeübte Person nach ungefähr 40 bis 60 supervidierten Punktionen eine hohe Trefferquote erreichen.

Zusammenfassung: Hintergrund: Die Diagnose einer Psoriasisarthritis (PsA) bei Patienten mit Psoriasis in alleiniger dermatologischer Betreuung ist unter Umständen verzögert. Wir entwickelten einen Patientenfragebogen für Patienten mit Psoriasis im ambulanten, dermatologischen Bereich zur Erfassung einer PsA (GEPARD, „GErman Psoriasis ARthritis Diagnostic questionnaire“). Ziel: Können mit dem GEPARD Patienten mit PsA aus dem ambulanten dermatologischen Patientenpool erfasst werden? Methoden: Wir evaluierten zunächst zwischen 2005 und 2007 den GEPARD an Patienten unserer Klinik für Dermatologie mit den Kriterien nach Vasey und Espinoza und verteilten ab Mai 2008 den Fragebogen in dermatologischen Praxen der Oberpfalz und Niederbayerns. Patienten, die den GEPARD ausfüllten, wurden zu einer rheumatologischen Visite eingeladen und – falls indiziert – auch durch Arthrosonographie, konventionelle Röntgenuntersuchung, MRT oder Skelettszintigraphie untersucht. Der Klassifikation einer PsA wurden in der klinisch-rheumatologischen Visite 2008 die CASPAR-Kriterien zugrunde gelegt. Ergebnisse: Im ersten Teil der Studie wurde ein Summengrenzwert für eine PsA berechnet. Im zweiten Teil wurde entsprechend den CASPAR-Kriterien bei 63% von 54 untersuchten Patienten eine PsA diagnostiziert. Nach der zusätzlichen apparativen Diagnostik konnte bei 79,6% (43 Patienten) eine entzündliche Gelenkmanifestation erfasst werden. Schlussfolgerung: Mit dem GEPARD können Patienten mit PsA aus dem ambulanten dermatologischen Bereich herausgefiltert werden.

Craniofacial morphology of patients with nevoid basal cell carcinoma syndrome (NBCCS) has sometimes been reported at clinical examination, but any investigation has described it on the basis of cephalometric measurements.

The boundaries of the aesthetic units of the face are often crossed after lower lip cancer surgery. The aim of this study was to compare the aesthetic and functional outcome after use of different operative techniques based on the concept of the aesthetic units of the face.

Objective: To assess facial growth and dentoalveolar development in two groups of patients with complete unilateral cleft lip and palate. Primary surgical treatment differed in the timing of hard palate closure.Design: Forty-three patients with unilateral cleft lip and palate were examined. Twenty-two patients underwent early one-stage closure of the hard and soft palate cleft (mean age 23.0 ± 4.7 months); in 21 patients, the hard palate closure was delayed to 86.3 ± 39.2 months of age. Lateral cephalograms and dental casts were consecutively analyzed at four stages between 6 and 18 years of age.Results: Lateral cephalometric analysis revealed no significant intergroup differences in the sagittal and vertical craniofacial dimensions at any time. Dental cast analysis showed constriction of the upper anterior arch width at the ages of 6 and 10 years in patients with one-stage surgical palate closure, but a difference could no longer be verified at the ages of 15 and 18 years.Conclusions: The transverse distances in the upper jaw developed initially more positively in the group with delayed hard palate closure, but it became apparent later that the transverse deficiency after one-stage palate closure could be compensated for. When considering surgical treatment in general, the advantages of the delayed hard palate closure must be weighed against criteria favoring the early one-stage closure of the hard and soft palate.

We present a process for high quality InGaN laser diodes on free standing GaN substrates with high reproducibility. We demonstrate a self-aligned process to contact lasers with ridge width <2 μm. The stability of the process allows us to optimize the epitaxial structure on GaN substrates and we achieve cw-threshold current densities of 2.9 kA/cm2 for 10 μm wide ridges and 4.7 kA/cm2 for 1.5 μm wide ridges. Cw-slope efficiencies of 1.0 W/A are achieved for both widths. Beside this we notice a reduction of the ideality factor and the forward bias linked to an improvement of the epitaxial interfaces. For maximum optical output we could achieve 3.4 W from one output facet at pulsed operation and a catastrophic optical mirror damage (COMD) level of 67 MW/cm2. Furthermore we observe a dependency of the COMD level from the pulse width corresponding to filament formation. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In this work we present degradation studies of GaN based blue-violet laser diodes grown on different substrates. By replacing the SiC substrate by GaN substrate, we change from hetero to homo epitaxy, while the threading dislocation density (TDD) is reduced by 3 orders of magnitude. A detailed analysis of small signal I –V curves shows an increase of non radiative (NR) recombination centers during aging for laser diodes on SiC substrate. This was not observed for lasers on GaN substrate due to the reduced TDD and therefore reduced number of diffusion channels for Mg-atoms, acting as NR recombination centers in the active region. With an improved epitaxial structure on GaN substrate, we increased the lifetime of our lasers by a factor of 10. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Diese Übersichtsarbeit zeigt, wie hormonelle und neuronale Faktoren, die im Stress verstärkt freigesetzt werden, die rheumatoide Arthritis und die juvenile idiopathische Arthritis ungünstig beeinflussen können. Dabei wird das Hauptaugenmerk auf Cortisol und Noradrenalin gelegt. Es wird dargelegt, dass zur Erklärung der durch Stress hervorgerufenen Veränderungen bei diesen beiden chronischen Krankheiten neben dem Immunsystem auch das endokrine System und das Nervensystem in die Überlegungen aufgenommen werden müssen. Die Defekte des endokrinen Systems und des Nervensystems bei rheumatoider Arthritis und juveniler idiopathischer Arthritis können an der Auslösung und Chronifizierung dieser Krankheiten maßgeblich beteiligt sein.

OBJECTIVE: Androgens such as dehydroepiandrosterone sulfate (DHEAS) and testosterone are markedly lower in postmenopausal women with rheumatoid arthritis (RA) than in controls. In contrast, compared to controls, serum levels of estrogens are normal or elevated in women with RA. Since tumor necrosis factor (TNF) alters production of these hormones, we investigated changes of these hormones during anti-TNF antibody (anti-TNF) therapy with adalimumab in longstanding RA. METHODS: In this longitudinal anti-TNF therapy study in 13 patients with long-standing RA without prior prednisolone (7 infusions of anti-TNF: Week 0, 2, 4, 6, 8, 10, and 12), we measured serum concentrations of interleukin 6 (IL-6), androstenedione, DHEA, DHEAS, free testosterone, estrone, and 17ß-estradiol. Levels of these hormones in patients were compared to serum levels of 31 age and sex matched healthy controls. RESULTS: Upon treatment with anti-TNF, there was an impressive decrease of clinical markers of inflammation, erythrocyte sedimentation rate, and serum levels of IL-6. Serum levels of DHEAS and free testosterone were markedly lower at baseline in patients compared to controls, but this did not change during anti-TNF therapy. Serum levels of DHEA and 17ß-estradiol were significantly elevated in patients compared to controls, but similarly, anti-TNF therapy did not change initially increased levels. Molar ratios of hormones, which reflect hormone shifts via converting enzymes, showed typical alterations at baseline, but did not change markedly during anti-TNF therapy. CONCLUSION: Longterm therapy with anti-TNF did not change altered serum levels of typical sex hormones in patients with RA, although baseline values were largely different. In patients with RA, this indicates that alterations of sex hormones and altered activity of respective converting enzymes are imprinted for a long-lasting period over at least 12 weeks.

Objectives. Rheumatoid arthritis (RA) is characterized by variable degrees of joint inflammation, joint destruction, progressive disability and premature death. Destruction of joint cartilage and bone may occur early during disease, as was shown in longitudinal studies of RA, and there is increasing consent among rheumatologists that early diagnosis and early initiation of therapy with disease-modifying anti-rheumatic drugs (DMARDs) can limit the severity of RA. Unfortunately, the currently used diagnostic and predictive indicators (clinical, laboratory and radiological) are of limited value for making an early diagnosis and prognosis of the disease course at the individual level, thus reducing optimal benefit from present and emerging therapies. Therefore, this review focuses on the multidisciplinary aspects of neuroendocrine–immune changes in RA.Methods. A Medline search was performed using the search terms ‘androgens’, ‘estrogens’, ‘sympathetic nervous system’, ‘sensory nervous system’, ‘prognosis’, ‘early rheumatoid arthritis’, ‘arthritis’ and ‘studies’ in various combinations. For the tabular overview, we only listed clinical studies focusing on endocrine and neuronal aspects.Results. In addition to the currently used predictive indicators, there is an abundant body of literature describing changes of the neuronal, endocrine and immune parameters during inflammatory diseases. Unfortunately, no longitudinal studies concerning neuroendocrine aspects have been done up to now.Conclusion. Parameters of the neuroendocrine system should be included in anticipated longitudinal clinical studies to find their true predictive value in early RA.

AbstractIn accordance with the Christian understanding ofhuman dignity, torture can be considered as a Iegitimale ethical alternative only if it does not serve as punishment or intend to elicit a juridical confession but rather intends to rescue actually threatened human life. However, the indirect relation between torture and potential rescue creates an unavoidable uncertainty ofknowing and deciding. This is the most important difference between torture on the one hand and both self-defence (Notwehr) and self-defence by proxy (Nothilfe) on the other. And precisely this difference excludes any ethical justification of torture. Who nevertheless- for ethical reasons- in a situation of serious conflict decides to command ortoperform torture must at least accept the juridical consequences of his or her decision.

Height and width of the ridge forming the laser diode waveguide determine threshold current density and lateral mode stability. We measure the optical near-field of the laser mode and simulate the two–dimensional mode distribution including waveguide losses and optical gain. The simulations show that weak guiding and not current spreading is the major cause for increased threshold current densities in weakly guided laser diodes. The near-field measurements show fundamental and higher order modes for nominally identical ridge laser diodes. We demonstrate that asymmetric losses in the waveguide bias the lateral mode competition towards higher order modes for an intermediate range of index guiding. This asymmetric damping is specific for (Al,In)GaN laser diodes due to absorption introduced in the p-waveguide by magnesium doping. This competition of lateral modes can also be seen spectrally as two longitudinal mode combs of different optical gain. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We investigate the epitaxial lateral overgrowth (ELOG) process on silicon carbide (SiC) to obtain defect reduced gallium nitride (GaN). The large wing tilt of about 4 degrees causes bunches of edge dislocations above the edge of the ELOG mask. The PL signal of these regions is diminished and broadened and a defect correlated emission line at about 3.4 eV is detected here exclusively. The GaN above the edge shows higher tensile stress than both the wing and the window regions. In order to reduce the wing tilt and to avoid its detrimental properties, the material of the ELOG mask was changed from SiO2 to SiNx. With the SiNx mask we were able to reduce the wing tilt by an order of magnitude to values far below 1 degree. The PL signal of the interface regions shows no sign of low quality material above the mask edge. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We study the facet degradation behavior of (Al,In)GaN multiple quantum well laser diodes. Water vapor causes a fast degradation due to facet oxidation of the uncoated facet. Degradation in an inert nitrogen atmosphere is slow and comparable to degradation of GaN laser diodes with coated facets. We also observe a reversible increase in the threshold current density due to a change in absorption caused by surface charges. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

OBJECTIVE:. In patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), 17β-estradiol was thought to play a dual pro- and antiinflammatory role depending on its concentration or probably conversion to downstream mitogenic 16a-hydroxyestrone or naturally occurring antiestrogens such as 2-hydroxyestrone. We compared renal excretion of these 2 types of estrogens in healthy subjects and patients with RA and SLE. Methods. In a prospective study with 30 patients with RA, 32 with SLE, and 54 healthy subjects, we measured urinary levels of 16a-hydroxyestrone and 2-hydroxyestrogens by enzyme immunoassay. We studied renal excretion to estimate the time-integral of hormone production. Results. Urinary concentration and total urinary loss of 2-hydroxyestrogens was 10 times higher in healthy subjects compared to patients with either SLE or RA irrespective of prior prednisolone treatment or sex. The urinary concentration and loss of 16a-hydroxyestrone did not differ between healthy subjects and patients with RA/SLE. The ratio of urinary 16a-hydroxyestrone/2-hydroxyestrogens was more than 20 times higher in RA and SLE than healthy subjects irrespective of prior glucocorticoid treatment or sex. Conclusion. This study in RA and SLE patients clearly demonstrates a large shift to mitogenic estrogens in relation to endogenous antiestrogens. Both steroids are converted from the precursor 17β-estradiol and estrone. In patients with RA and SLE, the magnitude of conversion to the mitogenic 16a-hydroxyestrone is greatly upregulated, which likely contributes to maintenance of the proliferative state in these diseases.

Adapting the Hakki–Paoli method for blue laser diodes we measure gain spectra for (In/Al)GaN on SiC substrate laser diodes in the low carrier density regime. From the measured longitudinal mode spacing we calculate the effective refractive index and can exclude a mode spacing ‘anomaly’. We demonstrate that the substrate has a considerable influence on the modal gain. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The carrier-induced refractive index change and the linewidth enhancement factor α are investigated by measuring the optical gain in an InGaN/GaN laser structure. Using the Kramers–Kronig relation we determined the maximum refractive index change to −0.0044 for a carrier density four times as large as the transparency carrier density. Though the change is higher than in conventional III–V structures, its influence on the waveguiding properties of the laser structure is small. The α factor varies between 2.1 and 6.3 in the investigated range of the carrier density and is thus comparable to that known from InGaAs/GaAs quantum well structures. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The current status of InGaN-MQW-laser diodes developed at Osram OS is presented. These lasers are grown on n-conducting SiC, enabling a vertical current path, cleaved facets and excellent heat spreading. The temperature rise during cw operation is measured for different mountings. A p-side up mounted diode with thermal resistance of 18 K/W showed 143 h of cw lasing at 1 mW optical power (T = 25 °C). DC and pulsed aging shows current as main degradation reason compared to heat for InGaN-LDs. Photoluminescence spectra of the quantum wells are being compared before and after degradation caused by current.

The waveguiding properties of nitride laser diodes are investigated for different Al concentrations in the cladding layers by calculating the optical field inside and by measuring the far field pattern behind the structures. The thicknesses of the p-cladding layer and of the electron blocking layer are also taken into account. The best optical confinement is reached for 10% and 12% Al in the n- and p-cladding layer, respectively. For these Al concentrations the full width at half maximum of the intensity distribution in the far field is increased by 15%. To prevent the leaking of the optical mode into the p-GaN cap layer the p-cladding layer should not be thinner than 270 nm.

We investigate the influence of chip size, substrate shaping and mounting techniques on the light extraction efficiency of large area InGaN-LED chips grown on 6H-SiC substrates. New techniques to achieve good light extraction for large chip areas are demonstrated and discussed. Applying these techniques to InGaN on SiC chips with 1 mm² size, we generate 150 mW of blue light and 33 lm of white light at a forward current of 350 mA. For efficient light extraction from the chip and for good thermal coupling the chip is soldered up-side down into a newly developed SMT package with a thermal resistance below 10 K/W.

Zusammenfassung. Hintergrund: Die lokalen Prozesse des angeborenen und adaptiven Immunsystems haben in der akuten Phase der rheumatoiden Arthritis (RA) eine wichtige pathogenetische Bedeutung. Neben dem Immunsystem könnten die Veränderungen entzündungshemmender neuroendokriner und neuronaler Systeme wichtige Komponenten darstellen, die für die Chronifizierung der Entzündung verantwortlich sind. Veränderungen: Wie bei vielen chronisch-entzündlichen Erkrankungen findet man bei der RA eine in Relation zum Grad der systemischen Entzündung zu niedrige Cortisol- und Androgensekretion. Zusätzlich ist im Synovialgewebe die Anzahl der entzündungshemmenden sympathischen Nervenfasern deutlich reduziert, wohingegen entzündungsfördernde sensible Nervenfasern vermehrt vorhanden sind. Das Gleichgewicht der synergistisch wirkenden entzündungshemmenden Systeme (Cortisol, Dehydroepiandrosteron, Androgene, sympathische Neurotransmitter) wird zugunsten von entzündungsfördernden Systemen (sensible Neurotransmitter, Östrogene) verschoben. Schlussfolgerung: Neue therapeutische Strategien könnten aus diesen Betrachtungen zur Pathogenese abgeleitet werden. Abstract. Background: Local innate and adaptive immune processes are of importance during the acute phase of rheumatoid arthritis (RA). In the advanced inflammatory phase alterations of systemic anti-inflammatory feedback mechanisms might be important features which may support chronic inflammation. Alterations: Similarly, like in other chronic inflammatory diseases, inadequately low cortisol and androgen serum levels can be detected in RA patients. In addition, there is a marked reduction of anti-inflammatory sympathetic nerve fibers in the inflamed joints paralleled by an enhanced number of pro-inflammatory sensory nerve fibers. Thus, an uncoupling of synergistically acting endocrine and neuronal, anti-inflammatory mechanisms (cortisol, dehydroepiandrosterone, androgens, sympathetic neurotransmitters) and a preponderance of pro-inflammatory mechanisms (estrogens, sensory neurotransmitters) may lead to chronic inflammatory disease. Conclusion: From this pathogenetic point of view new therapeutic strategies could be developed for the treatment of patients with RA.

Drawings of objects were presented in series of 54 each to 14 German speaking subjects with the tasks to indicate by button presses a) whether the grammatical gender of an object name was masculine ("der") or feminine ("die") and b) whether the depicted object was man-made or nature-made. The magnetoencephalogram (MEG) was recorded with a whole-head neuromagnetometer and task-specific patterns of brain activity were determined in the source space (Minimum Norm Estimates, MNE). A left-temporal focus of activity 150-275 ms after stimulus onset in the gender decision compared to the semantic classification task was discussed as indicating the retrieval of syntactic information, while a more expanded left hemispheric activity in the gender relative to the semantic task 300-625 ms after stimulus onset was discussed as indicating phonological encoding. A predominance of activity in the semantic task was observed over right fronto-central region 150-225 ms after stimulus-onset, suggesting that semantic and syntactic processes are prominent in this stage of lexical selection.

For group III nitride‐based lasers a new approach to realise DFB lasers and arrays is presented. Laterally coupled DFB (LC‐DFB) lasers are realised to minimise processing‐induced damage and to enable post‐processing adjustment of DFB laser parameters according to the material parameters achieved after epitaxial growth. These DFB laser arrays enable one to measure the threshold and the refractive index of electrically pumped DFB lasers over a wavelength emission range of 6 nm. DFB emission is demonstrated up to 70 °C and simultaneously a small temperature shift of the DFB mode. A significantly smaller tuning range is observed compared to optically pumped DFB lasers as well as a significantly red‐shifted gain region. Furthermore, the dispersion relation gradient determined, dneff/dλ, appears significantly steeper (by a factor of six) than in the optically pumped case. These effects are attributed to incompletely screened polarisation fields in electrically pumped InGaN/GaN lasers.