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1.
Unfallchirurg ; 125(4): 327-335, 2022 Apr.
Article in German | MEDLINE | ID: mdl-34989852

ABSTRACT

BACKGROUND: 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. AIM OF THE PAPER: 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. DISCUSSION: 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. CONCLUSION: 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.


Subject(s)
Cumulative Trauma Disorders , Hand Injuries , Occupational Diseases , Accidents , Cumulative Trauma Disorders/complications , Cumulative Trauma Disorders/etiology , Hand/blood supply , Hand Injuries/diagnosis , Hand Injuries/etiology , Hand Injuries/therapy , Humans , Occupational Diseases/diagnosis , Occupational Diseases/etiology , Syndrome , Ulnar Artery/injuries , Ulnar Artery/surgery , Workplace
2.
Phys Rev Lett ; 125(4): 045301, 2020 Jul 24.
Article in English | MEDLINE | ID: mdl-32794782

ABSTRACT

We demonstrate formation of the ideal split-vacancy configuration of the Sn-vacancy center upon implantation into natural diamond. Using ß^{-} emission channeling following low fluence ^{121}Sn implantation (2×10^{12} atoms/cm^{2}, 60 keV) at the ISOLDE facility at CERN, we directly identified and quantified the atomic configurations of the Sn-related centers. Our data show that the split-vacancy configuration is formed immediately upon implantation with a surprisingly high efficiency of ≈40%. Upon thermal annealing at 920 °C ≈30% of Sn is found in the ideal bond-center position. Photoluminescence revealed the characteristic SnV^{-} line at 621 nm, with an extraordinarily narrow ensemble linewidth (2.3 nm) of near-perfect Lorentzian shape. These findings further establish the SnV^{-} center as a promising candidate for single photon emission applications, since, in addition to exceptional optical properties, it also shows a remarkably simple structural formation mechanism.

3.
Phys Rev Lett ; 118(9): 095501, 2017 Mar 03.
Article in English | MEDLINE | ID: mdl-28306281

ABSTRACT

Radioactive ^{27}Mg (t_{1/2}=9.5 min) was implanted into GaN of different doping types at CERN's ISOLDE facility and its lattice site determined via ß^{-} emission channeling. Following implantations between room temperature and 800 °C, the majority of ^{27}Mg occupies the substitutional Ga sites; however, below 350 °C significant fractions were also found on interstitial positions ∼0.6 Å from ideal octahedral sites. The interstitial fraction of Mg was correlated with the GaN doping character, being highest (up to 31%) in samples doped p type with 2×10^{19} cm^{-3} stable Mg during epilayer growth, and lowest in Si-doped n-GaN, thus giving direct evidence for the amphoteric character of Mg. Implanting above 350 °C converts interstitial ^{27}Mg to substitutional Ga sites, which allows estimating the activation energy for migration of interstitial Mg as between 1.3 and 2.0 eV.

4.
Zentralbl Chir ; 142(3): 287-296, 2017 Jun.
Article in German | MEDLINE | ID: mdl-27429214

ABSTRACT

Swelling of the extremities is frequently observed after traumatic lesions and poses differential diagnostic challenges. Causes include seromas, haematomas and thromboses, as well as lymphostatic oedemas, which may become chronic if left untreated. These are characterized by a high percentage of protein and, over the long term, they can lead to considerable impairment and complications such as recurrent erysipelas as a result of fibrotic tissue rearrangement. Usually a clinical diagnosis is made, which presupposes that the symptoms are known. The most important treatment option is complete decongestive therapy, with manual lymphatic drainage and lymphological multicomponent bandaging being applied at least on a daily basis. Surgical intervention is only possible in individual cases. Because their chronic progression can lead to disablement, post-traumatic lymphoedemas are often the subject of assessments in private and statutory accident insurance proceedings. This paper explains the formation mechanism of post-traumatic lymphoedemas and provides an overview of differential diagnostic methods and current treatment recommendations. The authors also touch on insurance-related aspects.


Subject(s)
Lymphedema/therapy , Postoperative Complications/therapy , Wounds and Injuries/therapy , Combined Modality Therapy , Compression Bandages , Diagnosis, Differential , Disease Progression , Expert Testimony , Humans , Insurance, Accident , Lymphedema/diagnosis , Lymphedema/etiology , Manual Lymphatic Drainage/methods , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Wounds and Injuries/complications
5.
Unfallchirurg ; 118(10): 867-80, 2015 Oct.
Article in German | MEDLINE | ID: mdl-26377807

ABSTRACT

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.


Subject(s)
Accidents , Postthrombotic Syndrome/diagnosis , Postthrombotic Syndrome/therapy , Wounds and Injuries/diagnosis , Wounds and Injuries/therapy , Diagnosis, Differential , Evidence-Based Medicine , Humans , Postthrombotic Syndrome/complications , Thrombosis/diagnosis , Thrombosis/etiology , Thrombosis/therapy , Treatment Outcome , Wounds and Injuries/complications
6.
Internist (Berl) ; 55(3): 322-4, 326-8, 2014 Mar.
Article in German | MEDLINE | ID: mdl-24522559

ABSTRACT

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.


Subject(s)
Eczema/etiology , Eczema/prevention & control , Feeding and Eating Disorders/etiology , Hyperhidrosis/etiology , Lymphatic Diseases/complications , Lymphatic Diseases/drug therapy , Methylprednisolone/therapeutic use , Adult , Axilla , Eczema/diagnosis , Feeding and Eating Disorders/diagnosis , Feeding and Eating Disorders/prevention & control , Humans , Hyperhidrosis/diagnosis , Hyperhidrosis/prevention & control , Inguinal Canal , Lymphatic Diseases/diagnosis , Male , Treatment Outcome
7.
J Phys Condens Matter ; 25(41): 416001, 2013 Oct 16.
Article in English | MEDLINE | ID: mdl-24025311

ABSTRACT

As the intrinsic origin of the high-temperature ferromagnetism often observed in wide-gap dilute magnetic semiconductors becomes increasingly debated, there is a growing need for comprehensive studies on the single-phase region of the phase diagram of these materials. Here we report on the magnetic and structural properties of Fe-doped ZnO prepared by ion implantation of ZnO single crystals. A detailed structural characterization shows that the Fe impurities substitute for Zn in ZnO in a wurtzite Zn(1-x)Fe(x)O phase which is coherent with the ZnO host. In addition, the density of beam-induced defects is progressively decreased by thermal annealing up to 900 ° C, from highly disordered after implantation to highly crystalline upon subsequent annealing. Based on a detailed analysis of the magnetometry data, we demonstrate that isolated Fe impurities occupying Zn-substitutional sites behave as localized paramagnetic moments down to 2 K, irrespective of the Fe concentration and the density of beam-induced defects. With increasing local concentration of Zn-substitutional Fe, strong nearest-cation-neighbor antiferromagnetic interactions favor the antiparallel alignment of the Fe moments.


Subject(s)
Iron/chemistry , Iron/radiation effects , Magnetic Fields , Models, Chemical , Models, Molecular , Zinc Oxide/chemistry , Zinc Oxide/radiation effects , Computer Simulation
8.
Rev Sci Instrum ; 84(7): 073506, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23902062

ABSTRACT

The concept and functionality of an apparatus dedicated to emission channeling experiments using short-lived isotopes on-line at ISOLDE∕CERN is described. The setup is assembled in two functional blocks - (a) base stand including beam collimation, implantation and measurement chamber, cryogenic extension, and vacuum control system and (b) Panmure goniometer extension including maneuvering cradle and sample heating furnace. This setup allows for in situ implantation and sample analysis in the as-implanted state and upon cooling down to 50 K and during annealing up to 1200 K. The functionality of the setup will be illustrated with the example of establishing the lattice location of (56)Mn probes implanted into GaAs.

9.
Phys Rev Lett ; 102(6): 065502, 2009 Feb 13.
Article in English | MEDLINE | ID: mdl-19257601

ABSTRACT

We report on the lattice location of ion implanted Fe, Cu, and Ag impurities in germanium from a combined approach of emission channeling experiments and ab initio total energy calculations. Following common expectation, a fraction of these transition metals (TMs) was found on the substitutional Ge position. Less expected is the observation of a second fraction on the sixfold coordinated bond-centered site. Ab initio calculated heats of formation suggest this is the result of the trapping of a vacancy by a substitutional TM impurity, spontaneously forming an impurity-vacancy complex in the split-vacancy configuration. We also present an approach to displace the TM impurities from the electrically active substitutional site to the bond-centered site.

10.
Article in German | MEDLINE | ID: mdl-16523322

ABSTRACT

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).


Subject(s)
Curriculum/standards , Education, Medical/legislation & jurisprudence , Legislation, Medical , Licensure, Medical/legislation & jurisprudence , Models, Organizational , Specialization , Students, Medical , Educational Measurement , Europe , European Union , Forecasting , Germany , Health Care Reform/legislation & jurisprudence , Universities/organization & administration
11.
Phys Rev Lett ; 95(21): 215503, 2005 Nov 18.
Article in English | MEDLINE | ID: mdl-16384155

ABSTRACT

Arsenic has been reported in the literature as one of the few p-type dopants in the technologically promising II-VI semiconductor ZnO. However, there is an ongoing debate whether the p-type character is due to As simply replacing O atoms or to the formation of more complicated defect complexes, possibly involving As on Zn sites. We have determined the lattice location of implanted As in ZnO by means of conversion-electron emission channeling from radioactive (73)As. In contrast to what one might expect from its nature as a group V element, we find that As does not occupy substitutional O sites but in its large majority substitutional Zn sites. Arsenic in ZnO (and probably also in GaN) is thus an interesting example for an impurity in a semiconductor where the major impurity lattice site is determined by atomic size and electronegativity rather than its position in the periodic system.

12.
Article in German | MEDLINE | ID: mdl-11413703

ABSTRACT

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.


Subject(s)
Cardiopulmonary Resuscitation , Plasminogen Activators/therapeutic use , Pulmonary Embolism/therapy , Tissue Plasminogen Activator/therapeutic use , Aged , Femoral Fractures/surgery , Humans , Injections , Male , Plasminogen Activators/administration & dosage , Tissue Plasminogen Activator/administration & dosage
13.
Phys Rev Lett ; 84(7): 1495-8, 2000 Feb 14.
Article in English | MEDLINE | ID: mdl-11017551

ABSTRACT

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 67Cu was monitored following room temperature implantation into Si single crystals and annealing up to 600 degrees C. The majority of Cu was found close to substitutional sites, however, with a significant displacement, most likely 0.50(8) A along the <111> 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.

14.
J Comp Physiol A ; 185(1): 59-67, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10450611

ABSTRACT

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.


Subject(s)
Cognition/physiology , Ixodes/physiology , Odorants/analysis , Ticks/physiology , Vertebrates/physiology , Animals , Cattle , Female , Gas Chromatography-Mass Spectrometry , Larva , Lipids/chemistry , Skin/chemistry , Stimulation, Chemical
15.
Phys Rev B Condens Matter ; 50(4): 2176-2180, 1994 Jul 15.
Article in English | MEDLINE | ID: mdl-9976431
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