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  • 1
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We report on the first plasma experiments with the 100 TW laser at LLNL. We have experimentally investigated the interaction of 1 μm, 40 J, 400 fs, 5×1019 W/cm2 laser pulses with multilayer solid targets. Various diagnostics were used to characterize this interaction. An x-ray pinhole camera monitored laser spot size and plasma location on target. Part of the laser beam was split off to probe the density scale length of the preformed plasma. An optical system for Schlieren photography was designed to record the images of plasma with electron density gradients as low as 1021 cm−4 with characteristic scale length of 10 μm. The range of electron densities was 1018–2020 cm−3. CR-39 plastic track detectors were employed to measure the fast ion blowoff from the plasma. Using a foil-filter technique the proton energy spectrum up to 6 MeV was measured. It was found that the high energy tail usually had a narrow (FWHM ∼10°) cone of expansion. Energy conversion to the fast ions (above 0.5 MeV) was estimated to be ∼0.3%–1% of laser energy. In addition, charge-coupled devices were used for detecting characteristic K α emission caused by fast (〉1 MeV) electrons. (See article by K. Wharton for further discussion of the fast electron measurements.) Estimated fast electron yield ∼3%.© 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We report on experiments using the 100 TW laser at LLNL (40J, 400 fs, 5×1019 W/cm2 focal intensity) and planar multilayer targets (Mo/Sn) to study the generation and transport of electrons with MeV energies. Such fast electrons are of prime importance to many proposed applications, e.g., the fast ignitor fusion concept. X-ray emission spectroscopy is used to study the electron transport. Characteristic K α photon emission produced by the fast electrons in the front (Mo) and rear (Sn) layers of the target is measured with a charge-coupled device detector (single photon counting mode) to infer the electron energy deposition. The electron energy spectrum is measured by varying the thickness of the Mo layer to attenuate the electrons by different amounts. Penumbral imaging of the K α emission is used to give information about the angular distribution of the fast electron emission. Details of the measurement techniques and experimental results will be discussed and compared with modeling calculations.© 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1525-1314
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: The Mallee Bore area in the northern Harts Range of central Australia underwent high-temperature, medium-to high-pressure granulite facies metamorphism. Individual geothermometers and geobarometers and average P-T calculations using the program Thermocalc suggest that peak metamorphic conditions were 705–810C and 8–12 kbar. Partial melting of both metasedimentary and meta-igneous rocks, forming garnet-bearing restites, occurred under peak metamorphic conditions. Comparison with partial melting experiments suggests that vapour-absent melting in metabasic and metapelitic rocks with compositions close to those of rocks in the Mallee Bore area occurs at 800–875C and 〉9–10 kbar. The lower temperatures obtained from geothermometry imply that mineral compositions were reset during cooling. Following the metamorphic peak, the rocks underwent local mylonitization at 680–730C and 5.8–7.7 kbar. After mylonitization ceased, garnet retrogressed locally to biotite, which was probably caused by fluids exsolving from crystallizing melts. These three events are interpreted as different stages of a single, continuous, clockwise P-T path. The metamorphism at Mallee Bore probably occurred during the 1745–1730 Ma Late Strangways Orogeny, and the area escaped significant crustal reworking during the Anmatjira and Alice Springs events that locally reached amphibolite facies conditions elsewhere in the Harts Ranges.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 1573-1575 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on the development of a scanning eddy-current imaging system designed to detect deep subsurface flaws in conducting materials. A high transition temperature (high-Tc) superconducting quantum interference device (SQUID) magnetometer is employed to provide the required sensitivity at low frequencies, while a combination of small cylindrical high-Tc superconducting and μ-metal shields enable the instrument to be scanned in a magnetically noisy environment, rather than the object under test. The shields are arranged to prevent unwanted excitation and ambient noise fields from reaching the SQUID, and to enhance spatial resolution and minimize undesirable edge effects. Thus far, the instrument has successfully detected cracks and pits through 10 layers of aluminum, with a combined thickness of 5 cm at room temperature. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 53 (1997), S. 654-655 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 53 (1997), S. 1039-1041 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 53 (1997), S. 1462-1464 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1433-0563
    Keywords: Schlüsselwörter Blasenkarzinom ; Nierenzellkarzinom ; Prostatakarzinom ; Hodentumor ; Klinische Krebsregister ; Key words Bladder neoplasms ; Kidney neoplasms ; Prostatic neoplasms ; Testicular neoplasms ; Hospital cancer registries
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Since 1985 a special work group involved in the coordination of hospital cancer registries in Germany (AKKK) has been collecting, storing and analysing data on tumour patients, received from cancer centres, oncological departments and specialised practices. The documentation of tumour patients is based, among other things, on information concerning localisation, histological findings and tumour spread. The data are stored in a central database administered by the work group. At present it contains data on approximately 500,000 oncological patients. In the period from 1987 to 1992, 56,013 initial entries were made concerning patients with urological tumours. Of these cases, tumours of the kidney (n = 11,424) constituted 20.4 %. In 94.6 % of the cases, histological investigation revealed a renal cell carcinoma – pT1: 5.8 %; pT2: 53.6 %, pT3: 37.2 % and pT4: 3.4 %. Tumours of the urinary bladder (n = 16,246) constituted 29.0 % of all urological tumours. In 93.8 % of the cases a transitional cell carcinoma was detected – pTis: 1.0 %; pTa: 36.9 %; pT1: 29.6 %; pT2: 16.9 %; pT3: 11.4 %; pT4: 4.4 %. Transitional cell carcinomas of the ureter or of the collecting system (n = 1,846) constituted 3.3 % of the cases. The proportion of testicular tumours (n = 6,594) amounted to 11.8 %; 53.6 % of these germ-cell tumours (n = 6,281) were seminomas and 46.6 % were non-seminomas. In all, 66.3 % of the cases were lymph-node negative. Tumours of the prostate (n = 19,903) constituted 35.5 % of the cases. In the period from 1987 to 1992, the proportion of lymph-node-positive prostate carcinomas decreased from 39.8 % to 16.2 %. The detailed analysis of these data shows how the hospital cancer registries can support the discussion regarding diagnosis and therapy of urological tumours.
    Notes: Zusammenfassung Seit 1985 sammelt, speichert und analysiert die „Arbeitsgruppe zur Koordination Klinischer Krebsregister“ (AKKK) Daten von Tumorpatienten aus Tumorzentren, Onkologischen Schwerpunkten und spezialisierten Praxen. Die Datenerhebung erfolgt auf der Grundlage der „Basisdokumentation für Tumorkranke“, nach der u. a. Informationen über die Lokalisation, den histologischen Befund und die Ausbreitung eines Tumors registriert werden. Diese Angaben werden in der zentralen Datenbank der AKKK gespeichert; diese enthält z. Z. Daten zu etwa 500 000 onkologischen Patienten in Deutschland. Aus dem Zeitraum von 1986–1992 liegen Informationen zu 56 013 Ersterhebungen von Patienten mit urologischen Tumoren vor. Tumoren der Niere (n = 11 424) machten 20,4 % dieser Fälle aus. In 94,6 % der Fälle fand sich histologisch ein Nierenzellkarzinom. Bei 5,8 % der Fälle fand sich ein pT1-Tumor, bei 53,6 % ein pT2-Tumor, bei 37,2 % ein pT3-Tumor und bei 3,4 % ein pT4-Tumor. Tumoren der Harnblase (n = 16 246) machten 29,0 % aller urologischen Tumoren aus. Bei 93,8 % der Blasentumoren handelte es sich um ein Transitionalzellkarzinom (pTis: 1,0 %, pTa: 36,9 %, pT1: 29,6 %, pT2: 16,9 %, pT3: 11,4 %, pT4: 4,4 %). Transitionalzellkarzinome des Harnleiters oder des Nierenhohlsystems (n = 1846) machten 3,3 % der Nennungen aus. Der Anteil der Hodentumoren (n = 6594) am Gesamtkollektiv betrug 11,8 %; dabei handelte es sich bei 53,6 % der Keimzelltumoren (n = 6281) um Seminome und bei 46,6 % um Nichtseminome. Lymphknotennegativ waren 66,3 % dieser Fälle. Tumoren der Prostata (n = 19 903) stellten mit 35,5 % den größten Anteil am Kollektiv. Der Anteil lymphknotenpositiver Prostatakarzinome sank von 1987–1992 von 39,8 auf 16,2 %. Die detaillierte Analyse dieser Daten zeigt, wie die Arbeit der klinischen Krebsregister die Diskussion um Diagnose- und Therapiemaßnahmen an urologischen Tumoren unterstützen kann.
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  • 9
    ISSN: 1433-0563
    Keywords: Schlüsselwörter BPH ; Obstruktion ; Hochrisikopatienten ; TULAP ; Morbidität ; Key words Benign prostatic hypertrophy ; Obstruction ; High-risk patients ; Visual laser ablation of the prostate ; Morbidity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Between November 1993 and September 1995, we carried out visual laser ablation of the prostate (VLAP) in 72 high-risk patients (ASA 3–4; severe cardiovascular and/or pulmonary diseases) aged 60–88 years (mean 76.7 years); the prostate volume was 22–136 ml (mean 56 ml). The urinary peak flow rates (Qmax.) ranged from 2 to 15 ml/s (mean 4.4 ml/s) preoperatively; 42 patients (58.3 %) suffered from acute urinary retention for up to 2 weeks and had an indwelling catheter. The residual urinary volume (RUV) was 0–320 ml (mean 142.3 ml) in those 30 patients with spontaneous micturition. The International Prostate Symptom Score (IPSS) ranged from 10 to 33 (mean 21.8). In the first 37 patients, pressure-flow studies were carried out only in cases of doubt to verify obstruction. In the last 35 patients, pressure-flow studies were carried out in every case. Perioperatively, there was no appearance of blood loss of absorption of irrigation fluid. None of our patients needed transfusions or intensive care perioperatively. Further complications were not severe and could be handled without problems. In two patients with large benign prostate hypertrophy (BPH) a second operation (VLAP, no conventional transurethral prostatectomy) was necessary. After 6 weeks, 29.4 % of the patients suffered from symptomatic urinary tract infections (UTI). After 6 months, only 7.1 % of the patients had symptomatic UTI. After 6 weeks (n = 61), Qmax. was 6–34 ml/s (mean 15.3 ml/s), RUV was 0–230 ml (mean 51.5 ml), and the IPSS was 12.3 (8–28). After 3 months (n = 54), Qmax. was 9–45 ml/s (mean 19.8 ml/s), RUV was 0–96 ml (mean 31.6 ml), and the IPSS was 1–23 (mean 7.4). After 6 months (n = 52) Qmax. was 12–33 ml/s (mean 20.4 ml), RUV was 0–53 ml (mean 26.4 ml), and the IPSS was 1–12 (mean 4.1). VLAP provided no further risks for our high-risk patients, while Qmax., RUV, and IPSS were improved noticeably (improvement of more than 75 %). It represents a step forward in the treatment of obstructive BPH in high-risk patients. Particularly in high-risk patients with cardiac diseases, this procedure lessens the perioperative risk. Despite the minimal appearance of UTI after 6 months, UTI seemed to be the most important complication during the first few weeks after VLAP by virtue of the bothersome symptoms.
    Notes: Zusammenfassung Von 11/93 bis 09/95 führten wir bei n = 72 Hochrisikopatienten [ASA 3 und 4] mit schwerwiegenden kardialen und/oder pulmonalen Vorerkrankungen [Alter 76,7 (60–88) Jahre] eine TULAP durch. Das mittlere Prostatavolumen betrug 56 (22–136) ml. Präoperativ war der maximale Uroflow 4,4 (2–15) ml bei n = 30 Patienten, 42 Patienten (58,3 %) hatten eine Harnsperre. Der mittlere Restharn war 142,3 (0–320) ml und der „Internationale Prostata Symptom Score“ (IPSS) 21,8 (10–33). Bei den ersten 37 Patienten erfolgte eine Urodynamik nur bei Zweifeln an einer Obstruktion (9 Patienten), bei den letzten 35 Patienten führten wir immer eine Druck/Fluß-Messung durch, alle 44 urodynamisch untersuchten Patienten waren obstruktiv. Perioperativ traten weder Blutverlust noch Einschwemmung auf. Kein Patient benötigte Bluttransfusionen oder intensivmedizinische Behandlung. Bei 2 Patienten war eine Elektrokoagulation am Blasenhals erforderlich. Bei 2 Patienten mit großer BPH war eine Re-TULAP notwendig. Die Verweildauer des suprapubischen Katheters betrug 13 (3–65) Tage. Symptomatische Harnwegsinfektionen traten bei 29,4 % der Patienten 6 Wochen postoperativ auf; Nach 6 Monaten nur noch bei 7,1 %. Nach 6 Wochen (n = 61) stieg der maximale Uroflow auf 15,3 (6–34) ml/s, nach 3 Monaten (n = 54) auf 19,8 (9–45) ml/s nach 6 Monaten (n = 52) auf 20,4 (12–33) ml/s. Der Restharn fiel auf 51,5 (0–230) ml nach 6 Wochen, 31,6 (0–96) ml nach 3 und 26,7 (0–53) ml nach 6 Monaten. Der IPSS verbesserte sich auf 12,3 (8–28), 7,4 (1–23) und zuletzt auf 7,1 (1–12) nach 1/2 Jahr. Diese Erfahrungen weisen die TULAP als ein effektives und risikoarmes Therapieverfahren besonders für den kardial vorgeschädigten Hochrisikopatienten aus. Harnwegsinfektionen stellen den wichtigsten Morbiditätsfaktor dar.
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  • 10
    ISSN: 1432-1106
    Keywords: Temporomandibular ; Joint ; Biomechanics ; Gender ; Nociception
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Chronic pain in the temporomandibular (TM) joint is predominantly manifested in women. We examined biomechanical and neural factors that could contribute to this differential representation. Relationships between jaw rotation, soft tissue strains and soft tissue forces were examined in the goat TM joint. Strains were minimal until the jaw was rotated beyond the normal range of motion (7.25 deg). There were no significant differences in rotation-strain patterns in males and females. Stress developed as strains were introduced by jaw rotation. Gender differences were observed. Males manifested higher failure loads (15.94±1.98 and 11.37±2.02 N, for males and females respectively) and higher elastic stiffness than females (5.62±1.19 N/mm and 1.64±0.31 N/mm, for males and females respectively). Recordings were made from cell bodies in the trigeminal ganglion whose distal processes innervated the retrodiscal tissue of the temporomandibular joint of the goat (n=48). Nociceptor reactivity was characterized with respect to the capacity to transduce mandibular rotation (rotation-interval functions;n=29). On the basis of established relationships between rotation, strain and tissue forces, rotation-interval functions were transformed into strain-interval and force-interval functions. Comparisons were made between nociceptor properties grouped by gender. No differences in properties were observed when nociceptors were characterized with respect to jaw rotation; however, gender differences were obtained when nociceptor reactivity was characterized with respect to retrodiscal strains or forces. Consistent with smaller failure loads, nociceptors of retrodiscal tissues of females manifested a smaller range (1.12 vs 4.33 N), force to average (1.51 vs 4.64 N), force to minimum (0.95 vs 2.48 N) and force to asymptotic discharge (2.07 vs 6.81 N). Consistent with lower elastic stiffness, nociceptors of female tissues manifested higher average strain (54.4% vs 41.9%) and peak strain (74.0% vs 58.1%) to asymptotic discharge relative to those sampled from male tissues. The implications of these findings for TM joint injury and chronic pain are considered.
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