257 research outputs found
Development and Application of an airborne Differential Absorption Lidar for the Simultaneous Measurement of Ozone and Water Vapor in the Tropopause Region
No full textA new, combined, lidar system has been developed that is able to simultaneously measure profiles of ozone and water vapor onboard of a comparatively small aircraft. The concurrent measurement of these complementary trace species in the upper troposphere and lower stratosphere allows inferring exchange processes in the tropopause region.
Whereas an advanced H2O differential absorption lidar at 935 nm has successfully been developed and extensively tested at DLR in the past, we concentrate here on amending this lidar by addition of a UV channel to measure ozone.
The transmitter of the ozone DIAL is based on a near-IR optical parametric oscillator that is frequency-converted into the UV spectral range by intracavity sum frequency mixing. Hereby, a continuous UV tuning range of ~ 302-316 nm has been achieved. The average output power in this range is higher than 1 W corresponding to more than 10 mJ per pulse at a repetition rate of 100 Hz.
While airborne measurements are still pending, ground-based validation using both ozone sondes and ozone DIAL has successfully been performed and demonstrates the potential of this system
Night, Mother Cast List
No full textCast list for 'Night, Mother by Marsha Norman, directed by Don Ehret on May 11 & 13, 1993, and including a note from the play's author
Applications of high-resolution magic angle spinning MRS in biomedical studies II—Human diseases
No full textHigh-resolution magic angle spinning (HRMAS) MRS is a powerful method for gaining insight into the physiological and pathological processes of cellular metabolism. Given its ability to obtain high-resolution spectra of non-liquid biological samples, while preserving tissue architecture for subsequent histopathological analysis, the technique has become invaluable for biochemical and biomedical studies. Using HRMAS MRS, alterations in measured metabolites, metabolic ratios, and metabolomic profiles present the possibility to improve identification and prognostication of various diseases and decipher the metabolomic impact of drug therapies. In this review, we evaluate HRMAS MRS results on human tissue specimens from malignancies and non-localized diseases reported in the literature since the inception of the technique in 1996. We present the diverse applications of the technique in understanding pathological processes of different anatomical origins, correlations with in vivo imaging, effectiveness of therapies, and progress in the HRMAS methodology
Photon and Proton irradiation in Patient-derived, Three-Dimensional Soft Tissue Sarcoma Models
No full textAbstract Background Despite their heterogeneity, the current standard preoperative radiotherapy regimen for localized high-grade soft tissue sarcoma (STS) follows a one fits all approach for all STS subtypes. Sarcoma patient-derived three-dimensional cell culture models represent an innovative tool to overcome challenges in clinical research enabling reproducible subtype-specific research on STS. In this pilot study, we present our methodology and preliminary results using STS patient-derived 3D cell cultures that were exposed to different doses of photon and proton radiation. Our aim was: (i) to establish a reproducible method for irradiation of STS patient-derived 3D cell cultures and (ii) to explore the differences in tumor cell viability of two different STS subtypes exposed to increasing doses of photon and proton radiation at different time points. Methods Two patient-derived cell cultures of untreated localized high-grade STS (an undifferentiated pleomorphic sarcoma (UPS) and a pleomorphic liposarcoma (PLS)) were exposed to a single fraction of photon or proton irradiation using doses of 0 Gy (sham irradiation), 2 Gy, 4 Gy, 8 Gy and 16 Gy. Cell viability was measured and compared to sham irradiation at two different time points (four and eight days after irradiation). Results The proportion of viable tumor cells four days after photon irradiation for UPS vs. PLS were significantly different with 85% vs. 65% (4 Gy), 80% vs. 50% (8 Gy) and 70% vs. 35% (16 Gy). Proton irradiation led to similar diverging viability curves between UPS vs. PLS four days after irradiation with 90% vs. 75% (4 Gy), 85% vs. 45% (8 Gy) and 80% vs. 35% (16 Gy). Photon and proton radiation displayed only minor differences in cell-killing properties within each cell culture (UPS and PLS). The cell-killing effect of radiation sustained at eight days after irradiation in both cell cultures. Conclusions Pronounced differences in radiosensitivity are evident among UPS and PLS 3D patient-derived sarcoma cell cultures which may reflect the clinical heterogeneity. Photon and proton radiation showed similar dose-dependent cell-killing effectiveness in both 3D cell cultures. Patient-derived 3D STS cell cultures may represent a valuable tool to enable translational studies towards individualized subtype-specific radiotherapy in patients with STS
Die MIRAGE-Studie (MR-Linac-basierte Körperstereotaxie bei Prostatakarzinomen) – Precision at its best?
No full textThe role of image-guided robotic radiosurgery in the management of glomus jugulare tumors
No full textInnovative Anwendungsmöglichkeiten der Hochpräzisionsbestrahlung
No full textDie Hochpräzisionsbestrahlung mittels stereotaktischer Radiochirurgie (SRS), fraktionierter stereotaktischer Radiotherapie (FSRT) und Körperstereotaxie (SBRT) stellt heutzutage eine unverzichtbare Therapiemodalität in der modernen Onkologie dar. Im Kontext dieser Habilitation wurden die klinischen bzw. radioonkologischen Ergebnisse der Stereotaxie für Foramen magnum Meningeome, intramedulläre Metastasen, Nebennierenmetastasen, spinale Ependymome und Prostatakarzinomlokalrezidive analysiert. Darüber hinaus erfolgte eine erstmalige Betrachtung der gyroskopischen Radiochirurgie (GRS). Die dargestellten Arbeiten und Daten zeigen, dass die Stereotaxie auch im Rahmen seltener Indikationen und Tumorlokalisationen meist effektiv und sicher eingesetzt werden kann. Durch weitere Fortschritte auf dem Gebiet der funktionellen und nicht-funktionellen Bildgebung, adaptiven Strahlentherapie sowie der molekularpathologischen Diagnostik und biologischen Charakterisierung von Tumoren wird sich zusätzliches Potenzial zur Therapieoptimierung ergeben. Darüber hinaus wird es Aufgabe zukünftiger radioonkologischer Forschung sein, die Patientenselektion für die SRS, FSRT und SBRT weiter zu verfeinern und die Stereotaxie sinnvoll in den Kontext multimodaler Therapiekonzepte zu implementieren. Hierfür werden eine standardisierte und prospektive Datenerhebung und Evaluation von zentraler Bedeutung sein. Weiterhin sind technische Innovationen – wie bei der GRS oder Magnetresonanztomographie-gestützten Linearbeschleunigern ersichtlich – von großer Relevanz, um die Verfügbarkeit, Effektivität und Sicherheit der Hochpräzisionsbestrahlung weiter voranzutreiben
A Suspected Vestibular Schwannoma with Uncharacteristic Growth Dynamic and Symptom Severity: A Case Report
No full textContribution aux inventaires faunistiques : Les charançons de Normandie (Coleoptera Curculionidae, Rhynchitidae, Nemonychidae)
No full textThe author draws up the inventory of the Normandy Curculionidae s.l. (France) which he has caught or which have been given to him. Their places of origin are specified.L'auteur dresse l'inventaires des Curculionidae s.l. de Normandie (France) qu'il a capturés en 1979-1980 ou qui lui ont été donnés. Les localités sont précisées pour chaque espèce.Ehret Jean-Marie. Contribution aux inventaires faunistiques : Les charançons de Normandie (Coleoptera Curculionidae, Rhynchitidae, Nemonychidae). In: Bulletin mensuel de la Société linnéenne de Lyon, 65ᵉ année, n°1, janvier 1996. pp. 8-16
Impact of Extent of Resection on Survival in Brain Metastasis: An Analysis of 867 Patients
No full textBackground and objectives: The association between extent of resection (EOR) and outcomes after brain metastasis (BM) surgery remains unclear. The aim of this study was to examine the relation between EOR and overall survival (OS)/intracranial progression-free survival (IC-PFS) in this patient group. Methods: We included patients who underwent BM resection and had postoperative MRI <72 hours. Presence of any residual on MRI was defined as subtotal resection (STR) as opposed to gross total resection. Multivariable analyses were adjusted for known confounders. Post hoc analysis explored the effect size across different subgroups. A secondary outcome was the occurrence of leptomeningeal disease (LMD). Results: We included 867 patients; median age was 61 years (IQR 53-68), and median BM diameter was 3.0 cm (IQR 2.2-3.9). Extracranial metastases were present in 310 (35.8%) patients, and 365 (42.1%) received stereotactic radiosurgery (SRS) to the resection cavity. No residual on MRI was present in 345 patients (39.9%). In multivariable analysis, STR correlated with decreased IC-PFS (hazard ratio [HR] 1.32, 95% CI 1.13-1.55, P < .001) and OS (HR 1.28, 95% CI 1.08-1.53, P = .005) and a higher occurrence of LMD (odds ratio 1.74, 95% CI 1.10-2.76, P = .02). STR + SRS also correlated with decreased IC-PFS compared with gross total resection (HR 1.35, 95% CI 1.02-1.66, P = .04). In subgroup analysis, the strongest association between EOR and outcomes was observed in large (>3 cm) BMs, supratentorial BMs, and patients without extracranial disease. The use of cavity SRS or the number of BMs had little impact on this association. Conclusion: Residual tumor on postoperative MRI after BM resection correlated with worse IC-PFS and OS after adjusting for confounding variables. An increased prevalence of LMD may be a possible mechanism through which these patients experience worse outcomes
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