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The interest in Be as an impurity in GaN stems from the challenge to understand why GaN can be doped p type with Mg, while this does not work for Be. While theory has actually predicted an acceptor level for Be that is shallower than Mg, it was also argued that Be is not a suitable acceptor because its am-photeric nature, i.e. its tendency to occupy substitutional Ga as well as interstitial sites, would be considerably more pronounced than for Mg and hence lead to self-compensation. Using the emission channeling technique at the ISOLDE/CERN facility, we determined the lattice location of 11Be (t1/2 = 13.8 s) in different doping types of GaN as a function of implantation temperature. We find within an accuracy of 0.08 Å that the location of interstitial Be is the one predicted by theory. The room temperature interstitial fraction of 11Be was correlated with the GaN doping type, being highest (up to ~80%) in p type and lowest in n-GaN, thus giving direct evidence for the amphoteric character of Be. We find that interstitial 11Be fractions are generally much higher than for Mg, which confirms that indeed self-compensation should be consid-erably more pronounced for Be. With rising implantation temperature, an increasing conversion of interstitial to substitutional Be is observed, involving at least two clearly identifiable steps at 50–150 °C and 350–500 °C. This suggests that the migration of interstitial Be may be subject to two different activation ener-gies.

Melanoma stem cells (MSCs) are characterized by their unique cell surface proteins and aberrant signaling pathways. These stemness properties are either in a causal or consequential relationship to melanoma progression, treatment resistance and recurrence. The functional analysis of CD133+ and CD133- cells in vitro and in vivo revealed that melanoma progression and treatment resistance are the consequences of CD133 signal to PI3K pathway. CD133 signal to PI3K pathway drives two downstream pathways, the PI3K/Akt/MDM2 and the PI3K/Akt/MKP-1 pathways. Activation of PI3K/Akt/MDM2 pathway results in the destabilization of p53 protein, while the activation of PI3K/Akt/MKP-1 pathway results in the inhibition of mitogen-activated protein kinases (MAPKs) JNK and p38. Activation of both pathways leads to the inhibition of fotemustine-induced apoptosis. Thus, the disruption of CD133 signal to PI3K pathway is essential to overcome Melanoma resistance to fotemustine. The pre-clinical verification of in vitro data using xenograft mouse model of MSCs confirmed the clinical relevance of CD133 signal as a therapeutic target for melanoma treatment. In conclusion, our study provides an insight into the mechanisms regulating MSCs growth and chemo-resistance and suggested a clinically relevant approach for melanoma treatment.

Systemtherapien mit Immun-Checkpoint-Inhibitoren (ICI) haben in den letzten Jahren die Behandlung onkologischer und hamatologischer Erkrankungen revolutioniert. Ihre Wirkung besteht in einer Steigerung der Aktivitat des korpereigenen Immunsystems zur Tumorelimination. Als relevante, zugelassene Substanzen spielen insbesondere PD-1-, PD-L1- und CTLA-4-Inhibitoren eine Rolle. Hierdurch findet ein Wandel des Nebenwirkungsspektrums weg von klassischen Zytostatikaeffekten wie Panzytopenie oder Polyneuropathie hin zu bislang ungewohnlichen immunvermittelten komplexen Krankheitsbildern statt. Diese sogenannten „immune-related adverse events“ (irAEs) konnen samtliche Organsysteme befallen und klassische Autoimmunerkrankungen widerspiegeln. Sie zu erkennen und zugig einer passenden Therapie zuzufuhren, stellt eine Herausforderung im klinischen Alltag dar und bedarf eines intensiven interdisziplinaren Managements. Gerade Nephrologen sind als intensiv interdisziplinar tatige Internisten hierbei gefragt. Der vorliegende CME-Artikel soll das gesamte Spektrum sowohl der selteneren renalen als auch der haufigeren nicht-renalen immunvermittelten Nebenwirkungen darstellen und auf deren Diagnostik und Therapie vorbereiten.

Limited hand function as the result of occupational exposure or accidental injury could primarily be of vascular origin. Since it is quite rarely seen in the course of routine traumatology, special awareness of this is needed.The occupational diseases hypothenar/thenar hammer syndrome (occupational disease 2114) and vibration-induced vasospastic syndrome (occupational disease 2104) are presented on the basis of their etiological and pathogenetic characteristics, taking aspects of occupational medicine and expert opinion into consideration.Blunt force trauma to vascular structures of the hand can damage the tunica intima of the affected thenar or hypothenar arteries. Chronic exposure of the arms, hands and fingers to vibration can lead to the injury of nerve and vascular structures. Thermometry and pallesthesiometry are used in the diagnostics alongside methods of vascular medicine.Vascular entities can also play a role in the surgical assessment of the impact of an accident or of an occupational disease after exposure to vibration. Awareness of them can shorten the latency between the onset of symptoms and a definitive diagnosis.HINTERGRUND: Funktionseinschränkungen der Hand als Folge beruflicher Exposition oder Unfallschädigung können eine primär vaskuläre Ursache haben. Da sie vergleichsweise selten im Rahmen der traumatologischen Routine gesehen werden, ist eine besondere Sensibilität diesbezüglich erforderlich.Anhand ihrer ätiologischen und pathogenetischen Besonderheiten sollen die Berufskrankheiten (BK) Hypothenar‑/Thenar-Hammer-Syndrom (BK Nr. 2114) und vibrationsbedingtes vasospastisches Syndrom (BK Nr. 2104) unter arbeitsmedizinischen und gutachterlichen Aspekten vorgestellt werden.Stumpfe Gewalteinwirkung auf Gefäßstrukturen der Hand kann zu einer Schädigung der Tunica intima der betreffenden Arterien am Hypothenar bzw. am Thenar führen. Chronische Vibrationsexposition der Arme, Hände und Finger kann zu einer Schädigung von nervalen und vaskulären Strukturen führen. Zur Diagnostik kommen neben angiologischen Methoden die Thermometrie und die Pallästhesiometrie zur Anwendung.In der chirurgischen Begutachtung von Unfallfolgen oder Berufserkrankungen nach Vibrationsbelastungen können auch gefäßmedizinische Entitäten eine Rolle spielen. Deren Kenntnis kann für den Betroffenen die zeitliche Latenz zwischen Beschwerdebeginn und definitiver Diagnose verkürzen.

Systemic treatment with immune checkpoint inhibitors (ICI) has revolutionized the treatment of hematological and oncological diseases in recent years. The mechanism of action hinges on enhancing the natural ability of the immune system to eliminate malignant cells. The most important substances in this arena include inhibitors of PD‑1, PD-L1 and CTLA‑4. As a consequence, the spectrum of treatment-associated adverse reactions is shifting away from classical cytotoxic effects (e.g. pancytopenia and polyneuropathy) towards novel entities of immune-mediated complex diseases. These so-called immune-related adverse events (irAEs) can involve any organ system and mimic known classical autoimmune conditions. Timely recognition of irAEs is the key for rapid initiation of a suitable treatment and is especially challenging in the clinical routine as it requires an intensive interdisciplinary management. Nephrologists are particularly confronted with this kind of problem due to the highly interdisciplinary nature of their work. This article summarizes the broad spectrum of currently known renal and more frequently occuring non-renal forms of irAEs and aims to prime the reader on diagnostic and therapeutic options.

Head and neck squamous cell carcinoma (HNSCC) remains one of the most common malignancies worldwide. Although the treatment outcomes of HNSCC have improved in recent years, the prognosis of patients with advanced-stage disease remains poor. Current treatment strategies for HNSCC include surgery as a primary therapy, while radio-, chemo-, and biotherapeutics can be applied as second-line therapy. Although tumor necrosis factor-α (TNF-α) is a potent tumor suppressor cytokine, the stimulation of opposing signals impairs its clinical utility as an anticancer agent. The aim of this study was to elucidate the mechanisms regulating TNF-α‑induced opposing signals and their biological consequences in HNSCC cell lines. We determined the molecular mechanisms of TNF-α-induced opposing signals in HNSCC cells. Our in vitro analysis indicated that one of these signals triggers apoptosis, while the other induces both apoptosis and cell survival. The TNF-α-induced survival of HNSCC cells is mediated by the TNF receptor-associated factor 2 (TRAF2)/nuclear factor (NF)-κB-dependent pathway, while TNF-α-induced apoptosis is mediated by mitochondrial and non-mitochondrial-dependent mechanisms through FADD-caspase-8-caspase-3 and ASK-JNK-p53-Noxa pathways. The localization of Noxa protein to both the mitochondria and endoplasmic reticulum (ER) was found to cause mitochondrial dysregulation and ER stress, respectively. Using inhibitory experiments, we demonstrated that the FADD‑caspase-8‑caspase-3 pathway, together with mitochondrial dysregulation and ER stress-dependent pathways, are essential for the modulation of apoptosis, and the NF-κB pathway is essential for the modulation of anti-apoptotic effects/cell survival during the exposure of HNSCC cells to TNF-α. Our data provide insight into the mechanisms of TNF-α-induced opposing signals in HNSCC cells and may further help in the development of novel therapeutic approaches with which to minimize the systemic toxicity of TNF-α.

ZusammenfassungSchwellungen der Extremitäten sind nach traumatischen Läsionen häufig zu beobachten und stellen eine differenzialdiagnostische Herausforderung dar. Als Ursache sind neben Seromen bzw. Hämatomen und Thrombosen nicht selten auch lymphostatische Ödeme zu identifizieren, welche unbehandelt einen chronischen Verlauf nehmen. Sie sind charakterisiert durch einen hohen Eiweißanteil und führen langfristig durch fibrotischen Gewebeumbau zu erheblichen Behinderungen und Komplikationen wie rezidivierende Erysipele. Die Diagnosestellung erfolgt i. d. R. klinisch, was die Kenntnis der Symptomatik voraussetzt. Die wichtigste Behandlungsoption stellt die Komplexe Physikalische Entstauung dar. Hierbei kommen manuelle Lymphdrainage und lymphologische Mehrkomponentenverbände in mindestens täglicher Frequenz zur Anwendung. Nur in Einzelfällen sind auch chirurgische Interventionen möglich. Aufgrund ihres chronischen Verlaufs mit möglicher Invalidisierung sind posttraumatische Lymphödeme nicht selten Gegenstand der Begutachtung im Rahmen von Verfahren der gesetzlichen und privaten Unfallversicherung. Die vorliegende Arbeit erläutert die Entstehungsmechanismen posttraumatischer Lymphödeme und bietet eine Übersicht zu differenzialdiagnostischen Methoden und den aktuellen therapeutischen Empfehlungen. Zudem gehen die Autoren auf versicherungsrelevante Aspekte ein.

Phlebothrombosen stellen gefurchtete Komplikation bei Unfallverletzten dar, da sie fatale Lungenembolien verursachen konnen. Uber die Halfte der Betroffenen entwickelt uberdies im weiteren Verlauf ein postthrombotisches Syndrom (PTS). Neben der klinischen Einschatzung sollten dem Traumatologen auch die grundlegenden diagnostischen Methoden bekannt und die Deutung der internistischen Befunde gelaufig sein. Eine zentrale Rolle in der Diagnosestellung der Thrombose sowie auch in der Beurteilung funktioneller Einschrankungen spielt die farbcodierte Duplexsonographie. Weitere Informationen erbringen verschiedene phlebologische Verfahren. Die gutachterliche Beurteilung unmittelbarer, aber auch langfristiger Unfallfolgen erfordert haufig die Einordnung von Beinschwellungen. Nicht selten wird dabei ein PTS erstmalig diagnostiziert. Eine gefasmedizinische Zusatzbegutachtung ist haufig erforderlich. Die sozialmedizinische Wurdigung und versicherungsrechtliche Aspekte lassen dem Gutachter eine hohe Verantwortung zukommen.

Wir berichten von einem 28-jahrigen Mann mit zunehmender Inappetenz, Leistungsknick und indolenten Lymphknotenschwellungen im Axilla- und Inguinalbereich. An den Extremitaten bestand ein chronisches Ekzem. Unter dem klinischen und paraklinischen Verdacht auf ein malignes Lymphom wurde ein axillarer Lymphknoten exstirpiert. Die histopathologische Untersuchung zeigte das Bild einer dermatopathischen Lymphadenitis, eine Hautbiopsie erbrachte das histopathologische Bild eines chronischen Ekzems vereinbar mit einer Neurodermitis. Nach systemischer Methylprednisolon-Therapie waren der Hautbefund und die Lymphadenopathie rucklaufig. Aufgrund des histopathologischen Befunds und des klinischen Verlaufs stellten wir die Diagnose einer dermatopathischen Lymphadenitis, auch bekannt unter dem Synonym Pautrier-Woringer-Syndrom.

Phlebothromboses represent alarming complications in accident victims since they can cause fatal pulmonary embolisms. More than half of those affected also develop post-thrombotic syndrome in the course of the illness. In addition to making clinical assessments, the traumatologist should also have fundamental knowledge about diagnostic methods and be familiar with interpreting internal findings. Colour-coded duplex sonography plays a central role in diagnosing thrombosis and in assessing functional limitations. Further information can be gathered from various phlebological procedures. The expert evaluation of the immediate, as well as the long-term consequences of an accident frequently require leg swelling to be classified. It is not uncommon for post-thrombotic syndrome to be diagnosed for the first time during this process. An additional vascular appraisal is often required. An appreciation of social-medical and insurance-related aspects means a high degree of responsibility is placed on the expert.

Die arztliche Weiterbildung dient der Vertiefung und Spezialisierung der im Studium erworbenen Kenntnisse, Fahigkeiten und Fertigkeiten. Sie erfolgt in der Regel in praktischer Berufstatigkeit unter Anleitung erfahrener, zur Weiterbildung befugter Arzte und endet nach erfolgreich absolvierter Prufung mit dem Erwerb einer fuhrbaren Weiterbildungsbezeichnung. Die strukturellen Vorgaben, die im Rahmen der arztlichen Weiterbildung zu vermitteln sind, werden durch die Weiterbildungsordnung (WBO), einer von der Arztekammer beschlossenen Satzung, festgelegt. Die vom Deutschen Arztetag als Empfehlung beschlossene Musterweiterbildungsordnung dient dabei den Arztekammern in den einzelnen Bundeslandern als Richtschnur fur eine moglichst einheitliche Umsetzung des Weiterbildungsrechts. Dementsprechend sind landerspezifische Abweichungen moglich. Am Beispiel Baden-Wurttembergs werden die landesgesetzlichen Grundlagen und die Implementierung der WBO im Heilberufe-Kammergesetz beschrieben. Die weit reichenden Auswirkungen des Europarechts zeigt das Beispiel des Facharztes fur Allgemeinmedizin.

The lattice location of rare earths Tm in 3C– and 4H–SiC and Yb in 6H–SiC were studied using the emission channeling technique. Radioactive rare earth ions were implanted at the on-line isotope separator ISOLDE at CERN with an energy of 60 keV and fluences of 2×10 13 ions/cm 2 . In order to determine the lattice location of the implanted impurities, angular dependent electron yields around certain axes were recorded with conversion electrons arising in the decay 167 Tm– 167 Er ( t 1/2 =9.28 d) and 169 Yb– 169 Tm ( t 1/2 = 30.0 d). The effect of annealing on the normalized electron yields was studied up to 873 K for the 3C– and 4H–SiC samples and up to 1073 K for the 6H–SiC sample. In all cases the implanted rare earths are located on near substitutional silicon sites.

Atypical fibroxanthoma (AFX) is a rare, low-malignant, mesenchymal tumor of the dermis and is assigned to the group of fibrohistiocytic tumors. The tumor occurs especially in photodamaged skin on the scalp of elderly men. A clinical diagnosis is not possible due to a multitude of possible differential diagnoses (leiomyosarcoma, squamous cell carcinoma, spindle cell malignant melanoma, dermatofibrosarcoma protuberans). Immunohistochemical and histological examinations should be performed to confirm the diagnosis. The tumor shows a very good prognosis after complete excision. Micrographically controlled surgery is considered as the treatment of choice.

Aluminium salts are common adjuvants in all established inactivated vaccines. They are necessary to activate the humoral immune system. In the 1990s a Swedish study on an acellular vaccination against pertussis was started. Until 2013, 745 of 760,000 children with pruritic subcutaneous nodules were identified. In 77 % of these children a contact allergy to aluminium could be proven. Contact allergy to aluminium induced by vaccines causes pruritic subcutaneous nodules at the vaccination site. During infections of the upper respiratory tract the pruritus often escalates with inflammatory, erythematous and urticarial plaques.The use of solutions containing aluminium salts for specific immunotherapy is contraindicated in the case of contact allergy to aluminium. Intramuscular injections of inactivated vaccines can be employed to avoid granuloma formation.

A 28-year-old man presented with loss of appetite, night sweats, eczema, and axillary and inguinal lymph node swelling. The tentative diagnosis of malignant lymphoma was made. To confirm the diagnosis, extirpation of a lymph node and a skin biopsy were performed. Systemic treatment with methylprednisolone resulted in an improvement of eczema and lymph node swelling. Because of the histological findings and clinical course, we diagnosed dermatopathic lymphadenopathy, also known as Pautrier-Woringer syndrome.

We have used conversion electron emission channeling to determine the lattice location of $^{167m}$Er ($t_{1/2}$=2.28 s) in InP after 60 keV room temperature implantation of $^{167}$Tm ($t_{1/2}$=9.25 d) at a dose of 6.8 $\times 10^{12}$ cm$^{-2}$. Following annealing at temperatures above the major recovery step of the implantation damage at 100-150°C, we observe around 75% of Er on substitutional In sites. A smaller fraction of Er (7%) is found on substitutional P sites, the remainder on random sites. Annealing the unprotected InP crystal at temperatures above 250°C in vacuum causes a decrease in the channeling effects.

Channelling has, since its inception, proven to be a valuable tool in locating the geometric position of atoms in the crystal lattice. Allied with powerful theoretical models, it can yield detailed information on the positions that these impurities occupy. 111 In, a radioactive isotope with a conveniently short half-life, is an often-used probe of heavy-atom doping of materials. Previous work has centred on the lattice location of 111 In implanted in type IIa diamond. Theoretical calculations on this `pure' system have also recently been made. We have performed the first studies of 111 In implanted into various carefully selected, defect-rich diamond systems and obtained fractions for the sites occupied. The defect systems investigated include nitrogen in various configurations, boron, hydrogen and vacancies. The use of two-dimensional conversion-electron emission channelling (CEEC) has enabled the system to be studied in greater detail than with conventional one-dimensional CEEC. Coupled with the acquisition of the CEEC spectra for all the major channelling axes, this has yielded a comprehensive data set. The spectra are consistent with a pure substitutional fraction as well as another fraction, approximately 0.45 Afrom the substitutional along a 111 direction. Previous measurements observed these two components together as substitutional or `near-substitutional'. The data have been compared to simulated CEEC spectra and earlier quantum chemical calculations. The pure substitutional fraction is indicated to be in a defect-free configuration while the component displaced away from substitutional involves most probably the divacancy and another nearby defect. The results show no dependence on impurity type, even after annealing. If indium complexation with these defects does occur it is shown not to measurably affect the channelled spectra and thus the projected lattice location of the 111 In probe. The origin of the random fraction measured in previous studies is proposed to be partially due to In in different multi-vacancy complexes. Taken together, the data indicate the importance of vacancies (complexes) in the final configuration for In after implantation in diamond.

We have used conversion electron emission channeling to determine the lattice location of $^{167m}$Er ($t_{1/2}$=2.28 s) in GaAs after 60 keV room temperature implantation of $^{167}$Tm ($t_{1/2}$=9.25 d) at low doses (0.6-3 $\times 10^{13}$ cm$^{-2}$). Following a recovery step of the implantation damage at 200-300°C, we observe a large fraction of Er (45-68%) on substitutional Ga sites. A second fraction of Er is found on the T$_{As}$ sites (the tetrahedral interstitial sites with nearest As neighbours). The fraction on T$_{As}$ sites reaches a maximum of 12-23% following annealing at 500-600°C. At higher annealing temperatures the channeling effects decrease markedly, which we attribute to the well-known degradation of GaAs due to As evaporation.

A 73-year-old man has been suffering from a pulmonary adenocarcinoma for three years. He has been treated with the EGF-inhibitor erlotinib for the past 18 months. While taking this medication he developed a progressive papulopustular rash on his face and trunk which later spread to his thighs. Topical treatment with methylprednisolone and nadifloxacin, as well as short courses of systemic doxycycline and ciprofloxacin, led to marked improvement and control of his skin condition.

The lattice location of rare earth $^{167m}$Er in single-crystalline hexagonal ZnO was studied by means of the emission channeling technique. Following 60-keV room-temperature implantation of the precursor isotope $^{167}$Tm at doses of 1.3-2.8 $\times10^{13}$ cm$^{-2}$ and annealing up to 900°C, the angular distribution of conversion electrons emitted by the radioactive isotope $^{167m}$Er was measured by a position-sensitive electron detector. The conversion electron emission patterns from $^{167m}$Er around the [0001], [1102], [1101] and [2113] directions give direct evidence that the large majority of Er atoms (75-90%) occupies substitutional Zn sites.

ZnO single crystals were implanted with Mn, Co and Ni with fluences between 1 × 1016 cm-2 and 1 × 1017 cm-2 and energy of 200 keV. Results indicate that aggregation of transition metal ions in the as implanted state occurs only in the case of Ni. After an annealing stage to recover the ZnO structure aggregation occurs for the higher fluences of all implanted species. For lower concentrations paramagnetic behaviour with magnetic moments close to those of individual ions is observed. No polarised impurity band is formed as a result of the presence of transition metal ions and all samples show electrical conduction by carriers in extended states of ZnO. Significant values of magnetoresistance are measured at low temperatures, where electrical transport is described by hopping mechanisms between localized states. The sign of the magnetoresistance is dependent of the doping ion and is correlated with the observed aggregation.

The fulminant pulmonary embolism is one of the most feared complications of hospitalized patients. A high percentage of those patients need resuscitation within a short period of time. In such cases, the thrombolysis is a quickly attained therapeutical alternative to pulmonary embolectomy. A 77-year-old man with a surgically managed femoral fracture who suffered a massive pulmonary embolism, had to be resuscitated on the 11th postoperative day. Because of the fast confirmation of the diagnosis with the ECG and transthoracical echocardiography, it was possible to initiate thrombolysis with a bolus of 100 mg rt-PA immediately after the beginning of cardiac arrest and resuscitation. After 20 min of cardiopulmonary resuscitation (CPR), the patient could be stabilized under high dosage of catecholamines. The patient survived after prolonged intensive care treatment without severe bleeding complications, neither did he present any neurological deficit. We conclude that in the case of massive pulmonary embolism with small chance of resuscitation, the high-dose bolus injection of rt-PA could enrich the therapeutical possibilities.

For appoximately 6 month a 69-year old man had been suffering from an itching scaly skin change of the penis. Virological and histological examinations confirmed the diagnosis of an intraepithelial neoplasia induced by an infection with human papillomavirus (HPV) type 33. HPV type 33 is comparatively rarely detected in intraepithelial neoplasia. In anogenital lesions intraepithelial neoplasia should be considered and confirmed via histological and virological examinations.

A 25-year-old woman had suffered from a perianal ulcer for approximately 1 year. Topical and systemic treatments had been unsuccessful. Employing virologic and histologic techniques, we confirmed the diagnosis of an intraepithelial neoplasia. Anal intraepithelial neoplasia (AIN) is induced by carcinogenic human papillomaviruses. It can occur anywhere in the anogenital area. Because of its frequency, AIN is a crucial differential diagnosis for lesions of the anogenital area region failing to respond to standard therapies.

Specialized medical training serves to deepen the abilities and talents acquired during medical training. It usually takes place during professional activity under the guidance of experienced physicians authorized for specialized training and ends after a successfully completed examination with the acquisition of a specialized training title. The structural requirements, which are to be taught in the context of the specialized medical training, are specified in a statute (Weiterbildungsordnung), which was adopted by the chamber of physicians. The model Weiterbildungsordnung, decided upon by the German medical assembly (Deutscher Arztetag), serves as a recommendation in the individual States in Germany to achieve statutes as uniform as possible. The regional law bases and the implementation of the Weiterbildungsordnung in the Heilberufe-Kammergesetz are described by the example of the State of Baden-Württemberg. The extensive effects of the European law are illustrated by the example of the general practitioner (Arzt für Allgemeinmedizin).

The lattice location of $^{147}$Nd and $^{147^{*}}$Pm in thin-film, single-crystalline hexagonal GaN was studied by means of the emission channeling technique. The angular emission yields of $\beta^{-}$-particles and conversion electrons emitted by the radioactive isotopes $^{147}$Nd and $^{147^{*}}$Pm were measured using a position-sensitive detector following 60 keV room temperature implantation at a dose of 1 $\times 10^{13}$ cm$^{-2}$ and annealing at 900°C. The emission patterns around the [0001], [1102], [1101], and [2113] crystal axes give direct evidence that the majority (70%) of Nd and Pm atoms occupy substitutional Ga sites.

This article investigates experimentally and by device simulation the use of compensation devices in the phase shift ZVS bridge. Power MOSFETs reportedly fail at light load conditions due to the uncomplete clearance of the reverse recovery charge before turn-off. It is shown that compensation devices like CoolMOS/sup TM/ Solve this problem due to their significantly different device structure.

First basic investigations on lanthanide implanted cubic boron nitride were performed with focus on the site of the implanted ions as well as their luminescence behaviour. In order to investigate the lattice sites of lanthanides in c-BN, we implanted single crystal c-BN with radioactive 139Ce ions using the on-line isotope separator ISOLDE at CERN. After the samples were annealed at 1193 K, direct lattice location studies were performed using the conversion electron emission channeling technique and showed a near-substitutional fraction of the implanted ions of at least 10 %. Additionally, poly crystalline c-BN samples were implanted with stable Eu and Tm ions in order to investigate the luminescence properties of triply ionised lanthanides in the c-BN host. It is found that the annealing of the implanted samples at high temperature and high pressure results in strong luminescence of the Eu3+ ions in the orange and moderate luminescence of the Tm3+ ions in the blue. In case of the Eu implanted samples, the luminescence is assigned to the 5D0-7FJ intra-4f electron transitions of Eu3+, in case of the Tm implanted samples, detectable transitions are 1D2-3H6, 1D2-3F4, 1G4-3H6. of Tm3+.

The fulminant pulmonary embolism is one of the most feared complications of hospitalized patients. A high percentage of those patients need resuscitation within a short period of time. In such cases, the thrombolysis is a quickly attained therapeutical alternative to pulmonary embolectomy. A 77-year-old man with a surgically managed femoral fracture who suffered a massive pulmonary embolism, had to be resuscitated on the 11th postoperative day. Because of the fast confirmation of the diagnosis with the ECG and transthoracical echocardiography, it was possible to initiate thrombolysis with a bolus of 100 mg rt-PA immediately after the beginning of cardiac arrest and resuscitation. After 20 min of cardiopulmonary resuscitation (CPR), the patient could be stabilized under high dosage of catecholamines. The patient survived after prolonged intensive care treatment without severe bleeding complications, neither did he present any neurological deficit. We conclude that in the case of massive pulmonary embolism with small chance of resuscitation, the high-dose bolus injection of rt-PA could enrich the therapeutical possibilities.

The questing behaviour of ixodid ticks serves for identification and localisation of approaching hosts and is evoked by carbon dioxide, vibrations, visual and odour stimuli. In an olfactometer, we examined the specificity of the questing response of larvae of Boophilus microplus, a one-host tick which develops mainly on cattle, and Ixodes ricinus, a three-host tick with a broader host spectrum. While all mammalian odours tested were equally stimulatory for I. ricinus, B. microplus was clearly more activated by bovine odours. A phenolic fraction of bovine odour stimulated B. microplus only. Attractive components of the host odours were identified by exposing the ticks to single chemicals and mixtures. Single chemicals stimulated questing responses only at levels higher than the levels detected in the bovine odour. However, an artificial odour blend of 37 pure chemicals, diluted to concentrations at which the individual components were inactive, proved to be as effective as natural host odour for both tick species. Further fractionation of the blend revealed that the combinatory effect was achieved by only 7 compounds in both species. Although B. microplus responded to the same synergistic mixture of volatiles as I. ricinus, it showed significant higher sensitivity to the cattle-associated compounds 1-octen-3-ol and 2-nitrophenol and this might contribute to its host-specificity.

We report on the lattice location of ion implanted Cu in Si using the emission channeling technique. The angular distribution of $\beta^{-}$-particles emitted by the radioactive isotope $^{67}$Cu was monitored following room temperature implantation into Si single crystals and annealing up to 600°C. The majority of Cu was found close to substitutional sites, however, with a significant displacement, most likely 0.50(8) along the directions towards the bond center position. The activation energy for the dissociation of near-substitutional Cu is estimated to be 1.8-2.2 eV.

We report on the lattice location of 167Er in Si measured by conversion electron emission channeling. In both FZ and CZ Si, a high fraction of Er (>65%) occupies near-tetrahedral interstitial (T) sites directly following 60 keV room temperature implantation at doses of 6× 1012 cm−2 For higher doses, the as-implanted near-T fractions of Er visible by emission channeling are smaller, due to the beginning of amorphization. Following the recovery of implantation damage at 600°C, more than 70% of Er is found on near-T sites in both FZ and CZ Si. In FZ Si, Er exhibits a remarkable thermal stability and only prolonged annealing for several hours reduces the near-T fraction. On the other hand, annealing of CZ Si at 900°C for more than 10 minutes results in the majority of Er probes in sites of very low symmetry or disordered surroundings.

High quality YBa$_{2}$Cu$_{3}$O$_{6+x}$ (YBCO) superconducting thin films were implanted with the radioactive $^{197m}$Hg (T$_{1/2}$ = 24 h) isotope to low fluences of 10$^{13}$ atoms/cm$^{2}$ and 60 keV energy. The lattice location and stability of the implanted Hg were studied combining the Perturbed Angular Correlation (PAC) and Emission Channeling (EC) techniques. We show that Hg can be introduced into the YBCO lattice by ion implantation into unique regular sites. The EC data show that Hg is located on a highly symmetric site on the YBCO lattice, while the PAC data suggests that Hg occupies the Cu(1) site. Annealing studies were performed under vacuum and O$_{2}$ atmosphere and show that Hg starts to diffuse only above 653 K.