Study of water adsorption and capillary bridge formation for SiO(2) nanoparticle layers by means of a combined in situ FT-IR reflection spectroscopy and QCM-D set-up.

Water adsorption and capillary bridge formation within a layer of SiO2-nanoparticles were studied in situ by means of a combination of quartz crystal microbalance (QCM-D) with dissipation analysis and Fourier transformation infrared reflection absorption spectroscopy (FT-IRRAS). FT-IR data were employed to distinguish the "ice-like" and "liquid-like" contributions and to support the analysis of the QCM-D data concerning mass change and dissipation. Combined measurements show that for SiO2-nanoparticles with a diameter of about 250 nm, the formation of two adsorbed monolayers of water as well as bulk water leads to a rather linear increase in the dissipation for relative humidity values of up to 60% which is followed by a strong increase in dissipation during the actual liquid bridge formation. Subsequently, the dissipation drops again when the relative humidity is further increased to values >90%.

Outdoor Terrestrial Model Ecosystems are suitable to detect pesticide effects on soil fauna: design and method development.

Terrestrial Model Ecosystems (TME) were developed as one higher-tier option to detect and assess effects of pesticides on soil communities in a 1 year study using lindane (gamma-HCH) as a persistent and toxic reference pesticide. TME contained intact soil cores (diameter 300 mm, height 400 mm) including indigenous soil communities of undisturbed grassland. Forty units were placed outdoors between spring 2005 and 2006. The TME experiment was designed to provide data that fulfill the requirements of the revised European regulation on plant protection products (regulation 1107/2009/EEC replacing guideline 91/414/EC) with a focus on structural endpoints such as soil organisms and their community structure in case higher-tier evaluation is triggered. The key objective was to evaluate the dynamics and stability of species-diverse microarthropod communities of undisturbed grassland over at least 1 year after application. In grassland soils, less selection pressure towards insensitive species compared to arable land was presumed. Sufficient numbers of organisms and numerous TME replicates ensured that a statistical evaluation could be performed to estimate the sensitivity of the organisms upon application of lindane applied at high rates of 7.5 and 75 kg ai/ha. The application rates resulted in nominal concentrations of 10 and 100 mg ai/kg dry soil referred to the top 5 cm soil layer of 10 TME each; 20 untreated TME served as controls and were used to study the natural dynamics and the variability of populations under field conditions. Results showed that the grassland from which the soil cores were sampled contained communities of soil organisms marked by typical diversity of improved grassland. Lindane applied at excessive rates caused clear dose-related and long-lasting effects on the communities of microarthropods. On the contrary, lumbricids, the total feeding activity (bait lamina) and the growth of plant biomass were not affected up to 1 year after application. Based on the results of this study using a toxic reference insecticide, the methodology seems to be suitable for use in the regulatory context of the assessment of pesticides once protection goals, data requirements and the conceptual framework are defined.

Case report: ectopic pancreas with pseudocyst and pseudoaneurysm formation.

Ectopic pancreas is a rare congenital anomaly. It is usually asymptomatic, or presents with non specific gastrointestinal symptoms. We describe here a case of ectopic pancreas in the gastric antrum, with pseudocyst and pseudoaneurysm formation. This entity has not been reported previously in the literature.

Haemophiliac pseudotumour: two case reports of patients with moderate haemophilia A.

We report on two patients with haemophiliac pseudotumours who did not respond to intensified factor replacement therapy. Therefore the pseudotumours had to be removed surgically in both cases.

A delayed diagnosis of an unstable os odontoideum.

We report the case of a 2-year old child from Kuwait with known history of tetraparesis from birth. Radiological evaluation including computed tomographic scan and magnetic resonance imaging confirmed an unstable orthotopic os odontoideum which was complicated by cervical myelopathy.

[Evaluation of testicular volume in 0- to 18-year-old boys by sonography]. / Sonographische Bestimmung der Hodenmaße im Alter von 0 bis 18 Jahren.

BACKGROUND: Reference values are necessary in clinical practice in order to correctly evaluate testicular volume and detect disorders. OBJECTIVES: The objective of this prospective cross-sectional study was to evaluate reference values for testicular volume dependent on age, height, and weight in boys aged 0-18 years. MATERIAL AND METHODS: During their inpatient stay, the testes of 174 boys, who were free of disease or therapy that might influence testicular development, were examined by sonography. High resolution ultrasound transducers ranging from 7.5-14 MHz were used for evaluation. The testicular volume was calculated by the ellipsoid formula: length • width • height • (π/6). RESULTS: The subject age ranged from 0-18 years (average 7.1 ± 5.3 years). At the age of 0-8 years, the left testicular volume (1.2 ml) was less than the right testicular volume (1.3 ml). At the age of 13 years, the testicular volume of all subjects was over 3 ml. Left testicular volume of boys aged 16.5-18 years ranged from 7 to 22 ml and the right testicular volume ranged from 6 to 22 ml. CONCLUSION: Reference value tables of testicular volume dependent on age, and for the first time dependent on weight and height in boys aged from 0-18 years were compiled. Tables of testicular length, width, and height dependent on age are provided.

Topography of evoked brain activity during mental arithmetic and language tasks: sex differences.

We studied visual information processing using two different tasks in a group of 10 female and 10 male healthy, right-handed adults. Subjects solved arithmetic tasks shown sequentially on a computer monitor, and they also compared words presented as anagrams. The experimental design allowed us to compare the effects of reading or actively processing a given stimulus. Task difficulty was varied in three steps ('easy', 'medium', 'hard') after an independent group of 81 young adults had judged the stimulus material according to difficulty by answering questionnaires. Brain activity was recorded from an array of 30 electrodes extending from the inion to 5% anterior of F2. For each subject mean potentials were averaged off-line after screening the EEG for artifacts. Components were determined quantitatively as epochs of stable topography resulting in 10 independent components occurring within 1200 ms after stimulus onset. Significant effects were seen with field strength and scalp topography: simply reading the stimuli yielded significantly smaller amplitudes than when the subjects actively processed the same stimuli. Females had consistently larger global field power than males, and they also displayed different scalp field topography of various components. In addition, processing anagrams was accompanied by larger field strength than mental arithmetic. The scalp field distributions were also affected by sex, task type and difficulty indicating the activation of different neuronal assemblies during visual information processing of males and females. Many effects were seen at short latencies in the order of 70-120 ms indicating very early selective processing of visual stimuli where specific differences were introduced by sex and task parameters.

Multiply scattered light tomography and confocal imaging: detecting neovascularization in age-related macular degeneration.

A novel technique, Multiply Scattered Light Tomography (MSLT), and confocal Infrared Imaging are used to provide diagnostic information using a comfortable, rapid, and noninvasive method. We investigated these techniques in detecting neovascularization in age-related macular degeneration. The MSLT used a Vertical Cavity Surface Emitting Laser (VCSEL) at 850 nm, while the confocal imaging technique used either the VCSEL or a 790 nm laser diode. Both were implemented into the topographical scanning system (TopSS, Laser Diagnostic Technologies, Inc.) Confocal imaging with both lasers provided different information about neovascularization as a function of focal plane, and different also from MSLT.

Elevated levels of substance P in intraocular fluid in proliferative vitreoretinopathy.

Proliferative vitreoretinopathy is the most common reason for failure in retinal reattachment surgery. Since both substance P (SP) and SP receptors were found to be present in the human eye, and as pharmacological studies suggest an importance of SP for ocular functions, we investigated intraocular fluids for the presence of SP in eyes elected for cataract surgery, retinal detachment surgery and retina surgery for severe proliferative vitreoretinopathy (PVR) as well as in eyes with proliferative diabetic retinopathy (PDR). High performance liquid chromatography and radioimmunoassay (RIA) for SP immunoreactivities were performed. The SP mean concentration in intraocular fluid (IOF) of patients for cataract surgery (CS) was 2.2 fmol/ml, for retinal detachment (RD) was 2.7 fmol/ml and for PDR was 1.9 fmol/ml; significantly higher levels (mean concentration of 26.9 fmol/ml) were measured in eyes with PVR. HPLC analysis revealed two immunoreactive peaks coeluting with synthetic SP and SP-sulfoxide, indicating that RIA values represent authentic SP. We conclude that SP may play an important role in PVR. Since SP antagonists are known to inhibit a variety of SP effects in the eye, there might be a useful tool to reveal the importance of SP in this disease and, in this instance, a new possible treatment.

The effect of streptozotocin-induced diabetes mellitus on substance P and calcitonin gene-related peptide expression in the rat trigeminal ganglion.

Substance P (SP) and calcitonin gene-related peptide (CGRP) constitute the main sensory peptides in the trigeminal ganglion (TG). The objective of this study was to characterize peptidergic changes in the streptozotocin-induced diabetes mellitus rat model both quantitatively and qualitatively. Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (65 mg/kg) and the levels of SP and CGRP were measured by means of radioimmunoassay (RIA) in a time-dependent manner. Peptide immunoreactivities were characterized by high pressure liquid chromatography (HPLC). The expression of both neuropeptides was examined 5 weeks after streptozotocin injection using in situ hybridization with 35S-labelled oligonucleotides. Saline-injected rats served as controls. SP was significantly decreased in the diabetic rat TG, i.e. , a 44.6% (+/-10.9) decrease after 1 week, 40.2% (+/-11.8) after 3 weeks and 72.3% (+/-14.6) after 5 weeks. CGRP was decreased only after 5 weeks (19.6% decrease +/-3.9), whereas at later stages, both peptide levels returned to normal values. HPLC revealed one major peak coeluting with the synthetic peptides. By using in situ hybridization, a significantly increased signal of both peptide-encoding mRNAs was found (43.8%), which seems to act to restore a diabetes-associated depletion of neuropeptides in the diabetic rat TG. The decreased SP- and CGRP levels in the diabetic rat TG reflect a diabetes-associated deficit which may be clinically relevant. Diabetes mellitus is associated with a variety of ocular complications, even corneal complications, including decreased corneal sensitivity, which in many ways resemble those after interruption of the normal trophic innervation of the eye. Our results point to reduced availability of neuropeptides for corneal innervation and may thus support the idea of a partial loss of trophic influences from the trigeminal nerve in diabetics.

Complexation capacity of aquatic systems in dependence on different ligands and heavy metals - Electroanalytical investigations and statistical evaluation.

Heavy metals exist in natural waters in different species. Mobility and bioavailability of bound metals can be influenced by some complex factors in the aquatic environment. Therefore, it is useful to determine the complexation properties of various ligands influenced by different metals. The copper and zinc complexation capacity was determined for a natural ligand (fulvic acid) and anthropogenic pollutants (e.g. nitrilotriacetic acid and ethylenediaminetetraacetic acid). The interactions between several ligands and metal ions and their effects on the complexation capacity were analyzed in particular. Applying methods of experimental design, such as multifactorial plans, it is possible to determine influence and interaction of various parameters (e.g. concentration of zinc or copper) by a minimum number of experiments. Differential pulse polarography was used for the determination of the complexation capacity. Methods of parametric and robust multiple linear regressions were applied for the interpretation of the measured values.

Proton-detected 13C imaging using cyclic J cross polarization.

A new method is proposed permitting two- or three-dimensional Fourier transform imaging of protons coupled to 13C nuclei. In this way the spatial distribution of a preselected 13C resonance line can be imaged indirectly. The initial excitation as well as the detection of the signal are performed in the proton radiofrequency channel so that the utmost sensitivity is achieved. The principle is cyclic J cross polarization (CYCLCROP) for heteronuclear editing combined with a standard imaging sequence. The sequence has been implemented on a 4.7 T tomography system and successfully tested with a phantom as well as with biological objects with 13C in natural abundance.

Determination of fetal age by immunohistochemical estimation of surfactant-producing alveolar type II cells.

We monitored the immunohistochemically determined amount of surfactant-producing alveolar type II cells in human fetal lung using polyclonal antibodies against apoprotein B and C of human pulmonary surfactant. Lungs of 30 dead-born fetuses without lung affection aged between 15 and 38 weeks of gestation were evaluated and the surface density of surfactant-producing alveolar type II cells was determined by morphometry. In lungs of fetuses with a gestational age less than 22 weeks no relevant number of positively reacting cells could be found. Between the 22nd and 29th week a progressive increase with considerable inter-individual variability was observed. From the 30th week on the number of the type II pneumocytes appeared rather constant without further significant increase. We provide evidence that the immunohistochemical detection of surfactant-producing alveolar type II cells is useful for the determination of the age of unknown and especially fragmented fetuses: The lack of surfactant-producing alveolar type II cells in fetal lungs before the 22nd week allows a rather safe distinction between fetal lungs of higher age from those of lesser age. Between the 22nd and 29th week an age-dependent increase in the number of these cells occurs with wide inter-individual variability allowing only an approximate age determination. In particular, this may be an important piece of information in fragmented fetal corpses. Furthermore, the number of surfactant-producing alveolar type II cells provides additional information on pulmonary maturation and may thus be helpful in the estimation of a theoretical survival chance.

Application of ubiquitous computing in personal health monitoring systems.

A possibility to significantly reduce the costs of public health systems is to increasingly use information technology. The Laboratory for Information Processing Technology (ITIV) at the University of Karlsruhe is developing a personal health monitoring system, which should improve health care and at the same time reduce costs by combining micro-technological smart sensors with personalized, mobile computing systems. In this paper we present how ubiquitous computing theory can be applied in the health-care domain.