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Few Millimeters (few + millimeter)

Distribution by Scientific Domains

Polymers and Materials Science	40%
Medical Sciences	40%

Selected Abstracts

5 DIAGNOSTIC PITFALLS IN THE ECHOCARDIOGRAPHIC EVALUATION OF HYPERTROPHIC OBSTRUCTIVE CARDIOMYOPATHY (HOCM) REFERRED FOR CATHETER INTERVENTIONAL THERAPY

ECHOCARDIOGRAPHY, Issue 1 2004
G. Beer
Introduction: Generally, the diagnosis of typical HOCM with subaortic obstruction and a dynamic pressure gradient across the left ventricular outflow tract is made by noninvasive diagnostic procedures with great certainty by employing transthoracic (TTE) and/or transoesophageal (TEE) echocardiography. However, in patients with asymmetric septal hypertrophy pitfalls in echocardiographic examination may arise from several additional diseases as described in casuistic reports. To date systematic investigations in patients referred for catheter interventional therapy of HOCM are lacking. Patients and Methods: Therefore we investigated for the first time in a systematic study 200 symptomatic patients. (180 consecutive and 20 nonconsecutive patients; functional class 3 or 4 according to NYHA) with HOCM who were referred for this new catheter interventional therapy. In all patients TTE, bicycle exercise Doppler echocardiography and multiplane TEE were performed. Results: In 4 of 180 consecutive patients. (2.2%) discrete subvalvular membranous aortic stenosis (DSAS) (3 female patients and 1 male patient; age 20 to 58 years; mean septal diameter 19 mm; Sam-like motion in all 4 patients) was made. In all cases the diagnosis could be confirmed by surgical treatment. TEE evaluation was of crucial importance with demonstration of a typical subvalvular membrane that was situated a few millimeters below the aortic valve. In all cases a typical asymmetric septal hypertrophy mimicking HOCM was seen. Additionally, in 2 patients there was a conincidence of severe symptomatic valvular aortic stenosis and HOCM and in 1 patient a tunnel type of subvalvular aortic stenosis was present. Conclusion: These results show the potential pitfalls in echocardiographic diagnosis of HOCM. Especially, the frequency of DSAS in symptomatic patients referred for HOCM is unexpectedly high (2.2%). Especially in patients in whom TTE is of insufficient quality, investigation employing multiplane TEE with careful evaluation of the small poststenotic subvalvular area in HOCM is of crucial importance. This is of special significance prior to catheter interventional therapy, because in these patients surgical treatment is mandatory. [source]

Effect of Hypervelocity Impact on Microcellular Ceramic Foams from a Preceramic Polymer

ADVANCED ENGINEERING MATERIALS, Issue 11 2003
P. Colombo
A promising material for hypervelocity impact shields in spacecraft and satellites has been found in lightweight microcellular SiOC foams. The foam stops the projectile and the debris from the impacted bumper facesheet within a few millimeters (see Figure for a cross-section of the crater) at speeds up to 5.1 km,s,1. The impacted SiOC ceramic did not react with incoming debris, and no phase transformation or compositional change was observed. [source]

A case of erythema elevatum diutinum associated with breast carcinoma

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2005
Fikriye Yilmaz MD
A 53-year-old woman diagnosed with invasive ductal-type breast carcinoma was referred to our clinic with red,purple lesions on the hands and legs. She had neither pruritus nor pain. The first lesion developed on the dorsal hand. In the following days, new lesions appeared on the extensor surface of the legs. The patient had been treated with modified radical mastectomy and three courses of cyclophosphamide, adriamycin, and fluorouracil chemotherapy. Dermatologic examination revealed reddish-violaceous papules and plaques ranging from a few millimeters to 2 cm in diameter, bilaterally located on the dorsal hands, especially over the metacarpophalangeal and interphalangeal joints (Fig. 1). Multiple red,purple, circumscribed papules and plaques of various diameters were observed bilaterally over the shins (Fig. 2). The largest of these plaques showed an annular configuration. The nails showed distal subungual keratosis and yellow discoloration. The rest of the physical examination was normal. Figure 1. Violaceous papules and plaques on the dorsal hands Figure 2. Red,purple, circumscribed, papules and plaques over the shins A biopsy taken from the medial side of the shin revealed a predominantly neutrophilic infiltrate and nuclear dust around the dermal vessels and orthokeratotic stratum corneum (Fig. 3). Figure 3. Predominantly neutrophilic infiltrate and nuclear dust around the dermal vessels and orthokeratotic stratum corneum (hematoxylin and eosin stain, ×100) Complete blood count, routine biochemical tests and fasting lipids, serologic tests of bacterial and viral agents, serum electrophoresis, and serologic profiles for autoimmune connective tissue diseases revealed normal results. Mycologic examination of nail clippings did not show any evidence of fungal infection. In the light of our clinical and histopathologic findings, a diagnosis of erythema elevatum diutinum was made, and the patient was given topical clobetasol propionate therapy. Complete clearance was achieved in 3 weeks (Fig. 4). After six courses of cyclophosphamide, adriamycin, and fluorouracil chemotherapy, and radiotherapy, no recurrence of erythema elevatum diutinum lesions was observed. Figure 4. Healed lesion 3 weeks after high-potency topical glucocorticoids [source]

Transpressional tectonics of the Mineoka Ophiolite Belt in a trench,trench,trench-type triple junction, Boso Peninsula, Japan

ISLAND ARC, Issue 4 2005
Ryota Mori
Abstract Structures developed in metamorphic and plutonic blocks that occur as knockers in the Mineoka Ophiolite Belt in the Boso Peninsula, central Japan, were analyzed. The aim was to understand the incorporation processes of blocks of metamorphic and plutonic rocks with an arc signature into the serpentinite mélange of the Mineoka Ophiolite Belt in relation to changes in metamorphic conditions during emplacement. Several stages of deformation during retrogressive metamorphism were identified: the first faulting stage had two substage shearing events (mylonitization) under ductile conditions inside the crystalline blocks in relatively deeper levels; and the second stage had brittle faulting and brecciation along the boundaries between the host serpentinite bodies in relatively shallower levels (zeolite facies). The first deformation occurred during uplift before emplacement. The blocks were intensively sheared by the first deformation event, and developed numerous shear planes with spacing of a few centimeters. The displacement and width of each shear plane were a few centimeters and a few millimeters, respectively, at most. In contrast, the fault zone of the second shearing stage reached a few meters in width and developed during emplacement of the Mineoka Ophiolite. Both stages occurred under a right-lateral transpressional regime, in which thrust-faulting was associated with strike-slip faulting. Such displacement on an outcrop scale is consistent with the present tectonics of the Mineoka Belt. This implies that the same tectonic stress has been operating in the Boso trench,trench,trench-type triple junction area in the northwest corner of the Pacific since the emplacement of the Mineoka Ophiolite. The Mineoka Ophiolite Belt must have worked as a forearc sliver fault during the formation of a Neogene accretionary prism further south. [source]

Entwicklung hochverschleißbeständiger wolframschmelzkarbidbasierter Schichten auf Aluminiumbauteilen durch Plasma-Pulver-Auftragschweißen,

MATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 7 2007
S. Kondapalli Dipl.-Ing.
plasma transferred arc welding; wear-resistant coating; aluminium; composite coating; fused tungsten carbide Abstract Durch den Einsatz von Wolframschmelzkarbid können Funktionsflächen von Bauteilen mit stark abrasiven Beanspruchungen wirkungsvoll geschützt werden. Bereits seit vielen Jahren wird Wolframschmelzkarbid eingesetzt, um die Verschleißeigenschaften von Stahl zu verbessern. In diesem Artikel werden Ergebnisse von Untersuchungen zum Verschleißschutz von Aluminiumoberflächen mithilfe des Plasma-Pulver-Auftragschweißens von wolframschmelzkarbidbasierten Schichten vorgestellt. Die Wolframschmelzkarbid-Schichten werden mit zwei Methoden entwickelt, zum einen durch Dispergieren von Wolframschmelzkarbidpartikeln, zum anderen durch eine Kombination aus Dispergieren und Legieren von Verbundpulvern auf Wolframschmelzkarbidbasis. Die Schweißbarkeit der Pulversysteme wird für variierende Auftragschweißparameter und Karbidpartikelanteile untersucht. Im Anschluss erfolgt die Analyse der spezifischen Eigenschaften und der Verschleißbeständigkeit der entwickelten Schichten. Abschließend wird das Anwendungspotenzial am Beispiel von Führungsrollen dargestellt. Development of high wear-resistant FTC-based coatings on aluminium components using plasma transferred arc welding Nowadays, functional surfaces of components can be effectively protected from extreme wear with the help of fused tungsten carbide (FTC) coatings. The wear protection of steel components using FTC has been well known for many years. This paper presents the feasible study of improving the wear resistance of aluminium components with FTC particles using plasma powder arc welding. The FTC coatings are developed with two methods: one is the dispersion of carbide particles in aluminium and the other one is the combination of dispersing and alloying of FTC-based composite powders. In this research, coatings within a thickness range of a few millimeters are developed with varying process parameters and compositions of the filler materials. The developed coating systems are tested with regard to their specific properties and their wear resistance. Finally, their application potential is presented. [source]