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Anisotropic hydrodynamic function of dense confined colloids

Dense colloidal dispersions exhibit complex wave-vector-dependent diffusion, which is controlled by both direct particle interactions and indirect nonadditive hydrodynamic interactions mediated by the solvent. In bulk the hydrodynamic interactions are probed routinely, but in confined geometries their studies have been hitherto hindered by additional complications due to confining walls. Here we s

Sub-pixel correlation length neutron imaging : Spatially resolved scattering information of microstructures on a macroscopic scale

Neutron imaging and scattering give data of significantly different nature and traditional methods leave a gap of accessible structure sizes at around 10 micrometers. Only in recent years overlap in the probed size ranges could be achieved by independent application of high resolution scattering and imaging methods, however without providing full structural information when microstructures vary on

Dual phase grating interferometer for tunable dark-field sensitivity

Hard X-ray dark-field and phase contrast imaging using grating interferometry have shown great potential for medical and industrial applications. However, the wide spread applicability of the method is challenged by a number of technical related issues such as relatively low dose and flux efficiency due to the absorption grating, fabrication of high quality absorption gratings, slow data acquisiti

High aspect ratio metal microcasting by hot embossing for X-ray optics fabrication

Metal microstructured optical elements for grating-based X-ray phase-contrast interferometry were fabricated by using an innovative approach of microcasting: hot embossing technology with low melting temperature (280 °C) metal alloy foils and silicon etched templates. A gold-tin alloy (80 wt% Au/20 wt% Sn) was used to cast micro-gratings with pitch sizes in the range of 2 to20 μm and depth of the

Micrometer-resolution imaging using MÖNCH : Towards G2-less grating interferometry

MÖNCH is a 25 mm-pitch charge-integrating detector aimed at exploring the limits of current hybrid silicon detector technology. The small pixel size makes it ideal for high-resolution imaging. With an electronic noise of about 110 eV r.m.s., it opens new perspectives for many synchrotron applications where currently the detector is the limiting factor, e.g. inelastic X-ray scattering, Laue diffrac

Single shot x-ray phase contrast imaging using a direct conversion microstrip detector with single photon sensitivity

X-ray phase contrast imaging enables the measurement of the electron density of a sample with high sensitivity compared to the conventional absorption contrast. This is advantageous for the study of dose-sensitive samples, in particular, for biological and medical investigations. Recent developments relaxed the requirement for the beam coherence, such that conventional X-ray sources can be used fo

Anisotropic de Gennes Narrowing in Confined Fluids

The collective diffusion of dense fluids in spatial confinement is studied by combining high-energy (21 keV) x-ray photon correlation spectroscopy and small-angle x-ray scattering from colloid-filled microfluidic channels. We find the structural relaxation in confinement to be slower compared to the bulk. The collective dynamics is wave vector dependent, akin to the de Gennes narrowing typically o

Self-assembly nanostructured gold for high aspect ratio silicon microstructures by metal assisted chemical etching

Self-assembly gold nanostructured membranes are created to mechanically stabilize the catalyst movement during metal assisted chemical etching. This results in an improved vertical control of the etching profile for high aspect ratio silicon microstructures. The new method is a robust and cheap microfabrication for dense micro-patterns on a large area, such as diffraction gratings for hard X-ray p

Multiple scattering tomography

Multiple scattering represents a challenge for numerous modern tomographic imaging techniques. In this Letter, we derive an appropriate line integral that allows for the tomographic reconstruction of angular resolved scattering distributions, even in the presence of multiple scattering. The line integral is applicable to a wide range of imaging techniques utilizing various kinds of probes. Here, w

Serum levels of insulin-like growth factor I and insulin-like growth factor-binding protein 1 correlate with serum free testosterone and sex hormone binding globulin levels in healthy young and middle-aged men

OBJECTIVE: Administration of testosterone has been reported to increase serum levels of IGF-I in men with isolated hypogonadotrophic hypogonadism. An inverse relation between serum IGF-I and sex hormone binding globulin (SHBG) is seen in GH deficient children. The biological action of IGF-I is thought to be influenced by binding proteins, one of which is insulin-like growth factor-binding protein-

Quality of life in adults with growth hormone (GH) deficiency : response to treatment with recombinant human GH in a placebo-controlled 21-month trial

We examined the effect of GH supplementation on the psychological capacity and sense of well-being in 36 patients with adult-onset GH deficiency (GHD). Recombinant human GH was given in a 21-month cross-over, double blind trial, and quality of life was assessed by using three self-rating questionnaires: the Hopkins Symptom Check List (HSCL), the Nottingham Health Profile (NHP), and the Psychologic

Decreased serum testosterone and free triiodothyronine levels in healthy middle-aged men indicate an age effect at the pituitary level

In an attempt to study further the age-specific influence on the hypothalamo-pituitary-gonadal axis as well as the hypothalamo-pituitary-thyroid axis, we have now investigated young and middle-aged men, considering possible confounding factors. Both serum total testosterone, free testosterone and the total ratio of testosterone to sex-hormone binding globulin were significantly lower among middle-

Effect of acute desmopressin and of long-term thyroxine replacement on haemostasis in hypothyroidism

OBJECTIVE: Hypothyroidism can be complicated by bleeding symptoms such as easy bruising, menorrhagia and sometimes even a severe bleeding tendency with fatal outcome. Usually there is a prolonged bleeding time, or a low plasma concentration of coagulation factor VIII (FVIII) or von Willebrand factor (vWF). The aim of the present study was to investigate the acute haemostatic effect of desmopressin

Serum selenium concentrations in patients with autoimmune thyroiditis and non-toxic nodular goiter

Selenium (Se) deficiency is said to contribute to the atrophy of the thyroid gland in certain endemic goiter areas in Africa. To test the hypothesis that, a low Se intake could protect against goiter development in autoimmune thyroiditis, we analysed the Se concentration in 20 patients with the atrophic variant of lymphocytic thyroiditis, 23 patients with Hashimoto's thyroiditis and 23 patients wi

Contractions of English semi-modals : the emancipating effect of frequency

GERMAN SUMMARY: Gegenstand dieser Arbeit sind die verkürzten Formen (Kontraktionen) der englischen Modalausdrücke (‘semi-modals’) 'BE going to', 'HAVE got to' und 'want to'. Die Kontraktionen sind in der gesprochenen Sprache häufig und zeigen sich in den Schreibweisen 'gonna', 'gotta' und 'wanna'. Sie werden im Nordamerikanischen Englisch untersucht. Den Hintergrund der Arbeit bildet die GrammThe current restructuring of the English modal system has long been noted as an ongoing language change process. Semi-modal constructions such as 'BE going to' and 'HAVE got to' are textbook cases of grammaticalization. As grammaticalization comes with a rise in frequency, these semi-modals are also typical examples of the ‘reducing effect’ of frequency, which leads to the contracted forms 'gonna'

Increased prevalence of thyroid peroxidase antibodies (TPO-Ab) in women with glomerulonephritis

In a cross-sectional study adjusting for age, gender, and catchment area, the prevalence of thyroid antibodies was assessed in 51 consecutive subjects with biopsy-proven glomerulonephritis and in 112 control subjects admitted for extracorporeal shock-wave lithotripsy treatment for renal stones. Women with glomerulonephritis had both a significantly greater prevalence of thyroid peroxidase antibodi

Effects of adrenal function tests on the levels of endogenous digitalis-like substances and some pituitary hormones

In order to study the influence of the hypothalamic-pituitary-adrenal axis on the levels of endogenous digitalis-like substances (EDLS) in plasma and urine, eight healthy subjects (25-40 years old) were given dexamethasone 1 mg orally and tetracosactide (an ACTH analog) 0.25 mg i.v., on separate occasions. The circulating levels of EDLS, TSH, PRL and AVP following administration of either test dru

Immunoreactive endogenous digoxin-like substances : plasma levels are dependent on the hypothalamic-pituitary-adrenal axis for release and on kidney function for elimination

To identify factors that regulate the levels of immunoreactive digitalis-like substances (irEDLS) in body fluids, two studies were carried out. Plasma and urine levels of irEDLS were measured in uremic and normal subjects. Extracted material was fractionated (12 fractions) and assayed by digoxin radioimmunoassay. In four fractions, higher levels of irEDLS were found in uremic than in normal plasma

The role of estrogen in the TSH and prolactin responses to thyrotropin-releasing hormone in postmenopausal as compared to premenopausal women

The basal and TRH (Thyrotropin-Releasing Hormone) stimulated TSH (Thyrotropin) and PRL (Prolactin) responses (incremental area; IA) to 200 micrograms TRH was studied in 13 pre- and 13 postmenopausal women of 60 years of age. Both groups consisted of healthy women, none had goiter and all were negative for thyroid autoantibodies. The serum levels of TSH, T3, T4 and SHBG (sex hormone-binding globuli

Neuroendocrine effects in printing workers exposed to toluene

The effect of exposure to toluene on plasma concentrations of testosterone, prolactin, luteinising (LH) and follicle stimulating (FSH) hormones was investigated in 47 rotogravure printers (time weighted average air toluene below 80 ppm; blood toluene concentration post-shift 0.19-7.99 mumol/l) and compared with a reference group. Increasing exposure concentrations of toluene (concentrations less t