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S Klose

Publications and source records attributed to S Klose.

At least 19 recordsLinked to original sources
PubMed2006

An optical supernova associated with the X-ray flash XRF 060218.

Long-duration gamma-ray bursts (GRBs) are associated with type Ic supernovae that are more luminous than average and that eject material at very high velocities. Less-luminous supernovae were not hitherto known to be associated with GRBs, and therefore GRB-supernovae were thought to be rare events. Whether X-ray flashes--analogues of GRBs, but with lower luminosities and fewer gamma-rays--can also be associated with supernovae, and whether they are intrinsically 'weak' events or typical GRBs viewed off the axis of the burst, is unclear. Here we report the optical discovery and follow-up observations of the type Ic supernova SN 2006aj associated with X-ray flash XRF 060218. Supernova 2006aj is intrinsically less luminous than the GRB-supernovae, but more luminous than many supernovae not accompanied by a GRB. The ejecta velocities derived from our spectra are intermediate between these two groups, which is consistent with the weakness of both the GRB output and the supernova radio flux. Our data, combined with radio and X-ray observations, suggest that XRF 060218 is an intrinsically weak and soft event, rather than a classical GRB observed off-axis. This extends the GRB-supernova connection to X-ray flashes and fainter supernovae, implying a common origin. Events such as XRF 060218 are probably more numerous than GRB-supernovae.

Journal Article↗
PubMed2006

[Microalbuminuria in diabetes: setting the points for treatment].

Both type 1 and type 2 diabetes mellitus have a cumulative risk of 25-40% for the development of microalbuminuria 25 years into the disease. In type 2 diabetes micro- and macroangiopathic complications, and frequently hypertension, may also develop. This means that the risk of a type 2 diabetic with microalbuminuria of developing cardiovascular disease is three times greater than that of a diabetic with no renal involvement. Annual screening for microalbuminuria should therefore be obligatory. An increasing albumin excretion rate (AER) is considered an indication for an elevated cardiovascular risk. Studies have shown that the rate of cardiovascular events in diabetics with microalbuminuria and hypertension can be reduced only by the combined treatment of hypertension, hyperglycemia, hyperlipidemia and microalbuminuria.

Albuminuria↗
PubMed2006

A photometric redshift of z = 6.39 +/- 0.12 for GRB 050904.

Gamma-ray bursts (GRBs) and their afterglows are the most brilliant transient events in the Universe. Both the bursts themselves and their afterglows have been predicted to be visible out to redshifts of z approximately 20, and therefore to be powerful probes of the early Universe. The burst GRB 000131, at z = 4.50, was hitherto the most distant such event identified. Here we report the discovery of the bright near-infrared afterglow of GRB 050904 (ref. 4). From our measurements of the near-infrared afterglow, and our failure to detect the optical afterglow, we determine the photometric redshift of the burst to be z = 6.39 - 0.12 + 0.11 (refs 5-7). Subsequently, it was measured spectroscopically to be z = 6.29 +/- 0.01, in agreement with our photometric estimate. These results demonstrate that GRBs can be used to trace the star formation, metallicity, and reionization histories of the early Universe.

Journal Article↗
PubMed2005

A short gamma-ray burst apparently associated with an elliptical galaxy at redshift z = 0.225.

Gamma-ray bursts (GRBs) come in two classes: long (> 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at high redshift (z approximately 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core-collapse explosions of massive stars. In contrast, no short GRB had been accurately (< 10'') and rapidly (minutes) located. Here we report the detection of the X-ray afterglow from--and the localization of--the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect if the origin of this GRB is through the merger of neutron-star or black-hole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs.

Journal Article↗
PubMed2005

Giant intrasellar carotid aneurysm - an unusual cause of panhypopituitarism.

Carotid artery aneurysms represent a very rare cause of pituitary failure. We describe the case of a female patient harbouring a giant aneurysm of the left carotid artery that subsequently led to panhypopituitarism. Interestingly, the late postoperative course was complicated by severe hyponatremia, whose origin may have been due to inappropriate ADH secretion. This case illustrates the problems of diagnosis and postoperative handling of panhypopituitarism due to an intrasellar aneurysm.

Carotid Arteries↗
PubMed2003

[The harmonic scalpel in conventional thyroid surgery. Possibilities and advantages].

INTRODUCTION: Use of the harmonic scalpel is well established in surgery. The simple use and ability to save blood and time make this equipment usable in thyroid surgery, too. METHODS: In a prospective, nonrandomized study including 32 patients, operating time, weight of resected thyroid tissue, and complications were analysed. A classic surgery group (ligature and HF electrosurgery) was compared with an ultracision group. RESULTS: Mean+/-SD operative time was shorter in the harmonic scalpel group than in the conventional technique group (143.12+/-25.24 min vs 64.68+/-23.83 min, P<0.01). There was no difference between the two techniques regarding complications and patient characteristics. CONCLUSIONS: Use of the harmonic scalpel in thyroid surgery is a safe procedure. The possibility it presents of saving operative time without increasing complications has now been published in several studies.

Adult↗
PubMed2002

New advanced operational regime on the W7-AS stellarator.

A promising new plasma operational regime on the Wendelstein stellarator W7-AS has been discovered. It is extant above a threshold density and characterized by flat density profiles, high energy and low impurity confinement times, and edge-localized radiation. Impurity accumulation is avoided. Quasistationary discharges with line-averaged densities n(e) to 4 x 10(20) m(-3), radiation levels to 90%, and partial plasma detachment at the divertor target plates can be simultaneously realized. Energy confinement is up to twice that of a standard scaling. At B(t) = 0.9 T, an average beta value of 3.1% is achieved. The high n(e) values allow demonstration of electron Bernstein wave heating using linear mode conversion.

Journal Article↗
PubMed2002

[Laparoscopic adrenalectomy--experiences with transperitoneal approach].

INTRODUCTION: We report our results of laparoscopic anterior transperitoneal adrenalectomy. PATIENTS: Between 4/1996 to 05/2001, a laparoscopic adrenalectomy was performed in 34 patients (median age 48 years). The adrenalectomy was performed transperitoneally (31 unilateral; 3 bilateral). The adrenaline level was measured in 7 patients with a pheochromocytoma. RESULTS: All tumors (mean size 3.5 cm; 0.4 to 8.0 cm) could be extirpated by laparoscopy. 9 pheochromocytomas; 9 cortisol producing tumors (one patient with a Carney's syndrome); 7 Conn's adenomas and 9 incidentalomas constituted these tumors. In the first third of the observation period, the surgery lasted 176 (95-270) minutes, in the last third 82 (50-130) minutes (p < 0,01). We postoperatively observed the following complications: one abdominal wall hematoma at a port-site and one edematous pancreatitis after alteration of the pancreatic tail. The adrenaline level continually rose from the beginning of surgery to the ligature of the suprarenal vein. CONCLUSION: Transperitoneal adrenalectomy in benign tumors (< 8 cm) is our method of choice. The resulting learning curve allowed the performance of adrenalectomy within an acceptable operative time and without significant blood loss. The transperitoneal technique is safe and well reproducible. The cosmetical results are convincing. We recommend an early ligature of the suprarenal vein in a pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed2001

A pseudo-trigonal bipyramidally coordinated Pt atom in dicarbonylbis(octacarbonyl-mu-dicyclohexylphosphidodirhenio)platinum(II).

In the title compound, [PtRe4(C12H22P)2(CO)18] or [(mu-PCy2)(CO)8Re2]2Pt(CO)2 (Cy is cyclohexyl), two phosphido-bridged dirhenium groups are linked by a Pt(CO)2 unit and show different bonding patterns for stereochemical reasons. The Re--Re distances are 3.2620 (15) and 3.0739 (15) A, and the Pt--Re distances are 2.9165 (12), 2.9025 (15) and 2.8548 (13) A.

Crystallography, X-Ray↗
PubMed2001

Surface and biological evaluation of hydroxyapatite-based coatings on titanium deposited by different techniques.

Hydroxyapatite coatings have been deposited on titanium cp by plasma spray, sol-gel, and sputtering techniques for dental implant applications. The latter two techniques are of current interest, as they allow coatings of micrometer dimensions to be deposited. Coating morphology, composition, and structure have been investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). All coatings were homogeneous and exhibited a rough morphology suitable for implant applications. The sputtered (after annealing), plasma spray, and sol-gel coatings all showed diffraction peaks corresponding to hydroxyapatite. The surface contaminants were observed to be different for the different coating types. The sputtered coatings were found to have a composition most similar to hydroxyapatite; the sol-gel deposits also showed a high concentration of hydroxyl ions. A discrepancy in the Ca/P ratio was observed for the plasma spray coatings, and a small concentration of carbonate ions was found in the sputter-deposited coatings. The in vitro cell-culture studies using MG63 osteoblast-like cells demonstrated the ability of cells to proliferate on the materials tested. The sol-gel coating promotes higher cell growth, greater alkaline phosphatase activity, and greater osteocalcin production compared to the sputtered and plasma-sprayed coatings.

Alkaline Phosphatase↗
PubMed2000

The Discovery of an Embedded Cluster of High-Mass Stars near SGR 1900+14.

Deep I-band imaging to I approximately 26.5 of the soft gamma-ray repeater SGR 1900+14 region has revealed a compact cluster of massive stars located only a few arcseconds from the fading radio source thought to be the location of the soft gamma-ray repeater (SGR). This cluster was previously hidden in the glare of the pair of M5 supergiant stars (whose light was removed by point-spread function subtraction) proposed by Vrba et al. as likely associated with SGR 1900+14. The cluster has at least 13 members within a cluster radius of approximately 0.6 pc based on an estimated distance of 12-15 kpc. It is remarkably similar to a cluster found associated with SGR 1806-20. That similar clusters have now been found at or near the positions of the two best studied SGRs suggests that young neutron stars, which are thought to be responsible for the SGR phenomenon, have their origins in proximate compact clusters of massive stars.

Journal Article↗
PubMed2000

Retroperitoneal schwannoma presenting as an adrenal tumor.

A retroperitoneal tumor in the region of the adrenal gland was diagnosed in a 56-year-old woman. The patient had been suffering from a dull abdominal pain for nearly four weeks before consulting her family physician. Ultrasound, CT and MRI scans revealed a giant tumor of the right adrenal gland. Endocrine activity could not be demonstrated. The size of the tumor was suggestive of an adrenal carcinoma. The patient was referred for adrenalectomy and complete exstirpation of the retroperitoneal mass. The histological examination revealed characteristical findings of a benign schwannoma.

Adrenal Gland Neoplasms↗
PubMed2000

Plasma rotation in a plasma generator

The plasma rotation in a linear magnetic configuration has been investigated by means of high-resolution Doppler-spectroscopy. The effects of external device parameters and ion mass as well as the radial profiles have been studied. A simple model, based on the conservation of the total angular momentum, explains the main empirically determined dependences of the average angular velocity. The results are compared with the common multifluid description developed for hollow cathode discharges.

Journal Article↗
PubMed1999

Diagnostic strategies and surgical procedures in persistent or recurrent primary hyperparathyroidism.

The incidence of persistent or recurrent primary hyperparathyroidism reported in the literature lies between 1 and 10%. The main causes are represented by atypical locations or incorrect diagnosis of primary parathyroid hyperplasia. Since primary parathyroidectomy by an experienced surgeon has a success rate of 95%, there is no need for extended imaging studies prior to initial bilateral exploration. After confirming diagnosis of persistent or recurrent hyperparathyroidism exact localization studies are necessary. The most important procedures are ultrasonography, magnetic resonance imaging, technetium Tc99m sestamibi scintigraphy with a combined sensitivity of approximately 90%. In case of negative imaging results selective venous catheterization before reoperation can be performed. Reoperation by an experienced surgeon will be successful in 95% of cases.

Diagnostic Imaging↗
PubMed1998

Role of ultrasound in the diagnosis of thyroid autonomy.

The role and the different technical modes of ultrasound in thyroid autonomy are discussed. B-mode sonography is routinely employed to e.g. calculate thyroid and nodule volume, describe the echo pattern of both the thyroid gland and focal lesions and to visualize neighboring organs such as lymph nodes. Sonography thus possesses a complementary role to scintigraphy, since it may further aid in the localization of toxic adenomas, in particular when they are dorsally located or it may change the therapeutic decision. An example for the latter would be the preference of a surgical approach in case of cystic degeneration of an autonomously functioning nodule. Recently, color-coded doppler sonography using color flow mapping has been employed. With the advent of this technique it has become possible to describe the pattern of vascularization in thyroid focal lesions such as rim perfusion or internal hypervascularization. This technique harbors a high sensitivity for toxic adenoma exhibiting high internal blood flow, but does not appear to reliably discriminate between benign and malignant lesions. Nevertheless, further improvement of this technique may be promising in further characterizing the functional status of sonographically detected lesions and in the prognostic assessment of post-treatment outcome.

Adenoma↗