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The injection of urea-water solution (UWS) sprays into engine-close selective catalytic reduction (SCR) systems faces developers with complex challenges regarding two-phase flow and deposit formation. Potential spray impact on the static mixing elements inside the exhaust duct can lead to accumulation of liquid film and solid deposits, which may result in detachment of large UWS droplets at the trailing edges of the mixer blades. Present work focuses on the mechanisms of film and deposit formation within the scope of a joint study on spray preparation in the mixing section of SCR systems. A production type SCR exhaust system is used for optical investigations on gas flow and UWS droplets at the mixing element using Laser Doppler Anemometry (LDA) and Long Distance Microscopy (LDM) with a high-speed camera. Measured shear flows inside the mixing element are up to three times higher than the flow velocity upstream the mixer. Here, a decrease of droplet diameters of detached droplets is revealed with increased shear flow velocity. Characteristic urea deposits are created in a laboratory test bench and their surface structure is measured by use of Confocal Microscopy. Results show highly rough surface structures, which are used as input parameters together with the flow measurements to define the computational domain at the trailing edge of the mixer blades. Smoothed Particle Hydrodynamics (SPH) method is adopted for the numerical simulation of the transient two-phase flow and validated by LDM high-speed recordings of droplet detachment. Comparisons reveal a distinct influence of solid depositions on the re-atomization of the liquid film at the rear edge of the mixer blade. By interface resolving simulations with a phase-field method, the wall impingement of a sequence of large secondary droplets and associated film formation are studied. The results indicate that UWS film formation at the exhaust pipe wall may be reduced by hydrophobic surfaces and high gas velocities near the wall.

Initial permeability measurements on nanocrystalline soft magnetic Fe73.5Si13.5B9Nb3Cu1and Fe86Zr7B6Cu1alloys revealed that, in agreement with previous studies, in the optimum annealed state, the Fe –Si–B–Nb–Cu alloy exhibits much better soft magnetic behaviour than the Fe –Zr – B–Cu alloy. On the other hand, the density remained almost unchanged upon the amorphous– nanocrystalline transformation in Fe – Zr –B–Cu whereas a significant increase (~ 2%) occurred in Fe – Si–B–Nb – Cu. From X-ray diffraction and transmission electron microscopy studies, the amount of the residual amorphous phase, the lattice parameter, the internal stresses, and the grain morphology of the crystallized phase were found to evolve differently with increasing annealing temperature for the two alloys whereas their grain sizes were nearly the same for a given annealing temperature. It is pointed out that all these observed differences may also contribute to the differences in their soft magnetic behaviour. Furthermore, an analysis of the phases in the fully annealed state gave some hints to explain the different behaviour of density upon crystallization.

Due to the fast growing and ever changing innovation cycles, industries are changing their strategies from a product-centric to service-centric approach, leading to the emergence of product-service systems (PSS) which integrate services into physical technical systems. In the model-based development of PSS, various models are employed by different stakeholders to represent their views on the system. However, there is a high diversity of these models in both forms and contents. Among others, business models and technical models come in different levels of abstraction, and thus, are hard to align with each other. In this study, we propose an approach to support PSS development by relating business models to technical models using ontology. Web ontology language (OWL) is employed to describe PSS knowledge, the Query Language SPARQL and Semantic Web Rule Language (SWRL) are used for consistency checking and reasoning potential inconsistencies.

Summary: 1. The blood–brain barrier (BBB) is formed by brain capillary endothelial cells (ECs). There are various cell types, in particular astrocytes, but also pericytes and neurons, located in close vicinity to the capillary ECs which may influence formation and function of the BBB. Based on this consideration, this paper discusses various aspects of the influence of the surrounding cells on brain capillary ECs with special focus on the role of astrocytes.2. Based on the morphology of the BBB, important aspects of brain EC functions are summarized, such as transport functions and maintenance of low paracellular permeability. Moreover, various facets are discussed with respect to the influence of astrocytes, pericytes, microglia, and neurons on the BBB. Data on the role of glial cells in the ontogenesis of the BBB are presented subsequently. The knowledge on this subject is far from being complete, however, these data imply that the neural/neuronal environment rather than glial cells may be of importance in the maturation of the barrier.3. The role of glial cells in the induction and maintenance of the BBB is discussed under physiological as well as pathological conditions. Although the literature presents manifold evidence for a great variety of effects induced by astroglia, there are also many controversies, which may result from different cellular models and experimental conditions used in the respective studies. Numerous factors secreted by astrocytes have been shown to induce a BBB phenotype. On the molecular level, increased expression of barrier-relevant proteins (e.g., tight junction proteins) is documented in the presence of astrocyte-derived factors, and many studies demonstrate the improvement of physiological parameters, such as increased transendothelial resistance and decreased paracellular permeability, in different in vitro models of the BBB. Moreover, one has to take into account that the interaction of brain ECs and astrocytes is bi-directional, and that the other cell types surrounding the brain microvasculature also contribute to BBB function or dysfunction, respectively.4. In conclusion, it is expected that the present and future research focused on molecular mechanisms and signaling pathways will produce new and exciting insights into the complex network of BBB regulation: the cornerstone is laid.

A full-length cDNA encoding the porcine monocyte chemoattractant protein-1 (pMCPC-1) was isolated from growth-stimulated porcine cerebral capillary endothelial cells (cEC); the pMCP-1 cDNA showed 89% identity to human MCP-1 and was isolated by use of subtractive hybridization and differential screening of two phenotypically different sub-populations of cloned cEC. pMCP-1 was abundantly expressed in cEC grown in the presence of FCS, ECGF and heparin whereas lower expression was observed in cEC kept in FCS-supplemented medium only. As shown by Northern blot analysis, no pMCP-1 transcripts were present in total RNA derived from freshly isolated brain capillaries, large brain vessels or whole brain homogenate. MCP/JE expression was also demonstrated in ECGF/heparin-treated murine cEC. Astrocytes and smooth muscle cells grown in FCS-supplemented medium did not show MCP-1 expression. Treatment of porcine cEC with TNF-α increased pMCP-1 mRNA levels in a dose-dependent manner. These data further support the notion that cerebral capillary endothelial cells actively participate in processes of CNS host defense.

Ohne Zusammenfassung:

Viren sind weltweit verbreitete Erreger akuter Polyarthritiden. Häufig sind die Gelenkbeschwerden von anderen virustypischen Symptomen wie Fieber, Exanthemen, Myalgien oder Übelkeit begleitet. Es manifestieren sich aber nicht selten isolierte Polyarthritiden, die eine frühe rheumatoide Arthritis imitieren können. In Europa und Nordamerika gehören Parvovirus B19, Rubella, Hepatitis B und C zu den häufigsten arthritogenen Viren, während in Afrika, Australien, den westpazifischen Staaten und Südamerika die durch Stechmücken übertragenen Alphaviren endemisch sind und epidemische Polyarthritiden auslösen. Im Zuge des Fernreisetourismus haben diese Alphavirus-induzierten Arthritiden auch in Europa an Bedeutung zugenommen. Die Pathogenese viraler Arthritiden beinhaltet direkte Folgen der synovialen Virusinfektion (Zell-Lyse, lokale Immunkomplexformation, Induktion proinflammatorischer Zytokine) und auch indirekte Effekte durch Autoimmunreaktionen („Bystander-Aktivierung“ oder „Epitope Spreading“).

We have been able to estimate the thickness of nonfreezing interfacial layers of cyclohexane confined in nanoporous silica. This thickness was estimated from calorimetric measurements and simple geometrical analysis. The nonfreezing layers coexist with molecules that can undergo phase transition when the pore size of the confining medium is larger than 3.5 nm. In agreement with the Gibbs−Thompson equation, the melting and freezing temperatures of the molecules capable of undergoing phase transition scale linearly with the inverse pore size of the silica. Experimentally determined (apparent) ΔH, however, seems to vary with physical size, which contradicts the inherent assumptions in the Gibbs−Thompson equation. Corrections to account for the presence of nonfreezing layers of molecules with thickness ca. 2.14 ± 0.2 nm not only leads to a ΔHinvariant with physical size, but it also provides insight into density variation due to confinement.

We evaluated the long-term functional outcome in 118 patients treated for osteosarcoma or Ewing’s sarcoma in the extremities a minimum of five years after treatment. We also examined if impaired function influenced their quality of life and ability to work.The function was evaluated according to the Musculoskeletal Tumor Society (MSTS) score and the Toronto Extremity Salvage Score (TESS). Quality of life was assessed by using the Short Form-36 (SF-36).The mean age at follow-up was 31 years (15 to 57) and the mean follow-up was for 13 years (6 to 22). A total of 67 patients (57%) initially had limb-sparing surgery, but four had a secondary amputation. The median MSTS score was 70% (17% to 100%) and the median TESS was 89% (43% to 100%). The amputees had a significantly lower MSTS score than those with limb-sparing surgery (p < 0.001), but there was no difference for the TESS. Tumour localisation above knee level resulted in significantly lower MSTS scores and TESS (p = 0.003 and p = 0.02, respectively).There were no significant differences in quality of life between amputees and those with limb-sparing surgery except in physical functioning. Of the patients 11% (13) did not work or study. In multivariate analysis, amputation, tumour location above the knee and having muscular pain were associated with low physical function.We conclude that most of the bone tumour survivors managed well after adjustment to their physical limitations. A total of 105 are able to work and have an overall good quality of life.

We retrospectively studied local recurrence of giant cell tumour in long bones following treatment with curettage and cementing in 137 patients. The median follow-up time was 60 months (3 to 166). A total of 19 patients (14%) had at least one local recurrence, the first was diagnosed at a median of 17 months (3 to 29) after treatment of the primary tumour. There were 13 patients with a total of 15 local recurrences who were successfully treated by further curettage and cementing. Two patients with a second local recurrence were consequently treated twice. At the last follow-up, at a median of 53 months (3 to 128) after the most recent operation, all patients were free from disease and had good function.We concluded that local recurrence of giant cell tumour after curettage and cementing in long bones can generally be successfully treated with further curettage and cementing, with only a minor risk of increased morbidity. This suggests that more extensive surgery for the primary tumour in an attempt to obtain wide margins is not the method of choice, since it leaves the patient with higher morbidity with no significant gain with respect to cure of the disease.

We report positive and negative factors associated with the most commonly-used methods of reconstruction after pathological fracture of the proximal femur. The study was based on 142 patients treated surgically for 146 metastatic lesions between 1996 and 2003. The local rate of failure was 10.3% (15 of 146). Of 37 operations involving osteosynthetic devices, six failed (16.2%) compared with nine (8.3%) in 109 operations involving endoprostheses. Of nine cases of prosthetic failure, four were due to periprosthetic fractures and three to recurrent dislocation. In the osteosynthesis group, three (13.6%) of 22 reconstruction nails failed. The two-year risk of re-operation after any type of osteosynthesis was 0.35 compared with 0.18 after any type of endoprosthetic reconstruction (p = 0.07). Endoprosthetic reconstructions are preferable to the use of reconstruction nails and other osteosynthetic devices for the treatment of metastatic lesions in the proximal third of the femur.

Trypanothione reductase is a flavoenzyme unique to trypanosomatid parasites. Here we show that unsaturated Mannich bases irreversibly inactivate trypanothione reductase from Trypanosoma cruzi, the causative agent of Chagas' disease. The inhibitory potency of the compounds strongly increased upon storage of the DMSO stock solutions. HPLC, NMR, and mass spectrometry data of potential intermediates revealed a divinyl ketone as the active compound inactivating the enzyme. ESI- and MALDI-TOF mass spectrometry of trypanothione reductase modified by the Mannich base or the divinyl ketone showed specific alkylation of the active site Cys52 by a 5-(2‘chlorophenyl)-3-oxo-4-pentenyl substituent. The reaction mechanism and the site of alkylation differ from those in Plasmodium falciparum thioredoxin reductase where the C-terminal redox active dithiol is modified. After deamination, unsaturated Mannich bases are highly reactive in polycondensation with trypanothione. Interaction of these compounds with both trypanothione and trypanothione reductase could account for their potent trypanocidal effect against Trypanosoma brucei.

In order to validate computational fluid dynamics (CFD) calculations, accurate velocity measurements were performed in a so called pre-swirl system. The objective was to determine the three-dimensional velocity field in the enclosed rotor–stator gap by using an adapted stereo particle image velocimetry (stereo PIV) setup. Particular attention was invested in the design of the optical access, thus, offering interesting possibilities to investigate various geometrical configurations of the pre-swirl system. The measurements impressively showed the spreading of the jet inside the wheelspace and the unsteady aspect of the flow, confirming that stereo PIV can successfully be applied in an enclosed rotor–stator system.In order to validate computational fluid dynamics (CFD) calculations, accurate velocity measurements were performed in a so called pre-swirl system. The objective was to determine the three-dimensional velocity field in the enclosed rotor–stator gap by using an adapted stereo particle image velocimetry (stereo PIV) setup. Particular attention was invested in the design of the optical access, thus, offering interesting possibilities to investigate various geometrical configurations of the pre-swirl system. The measurements impressively showed the spreading of the jet inside the wheelspace and the unsteady aspect of the flow, confirming that stereo PIV can successfully be applied in an enclosed rotor–stator system.

The physics of the impingement process of small hydrocarbon droplets is mostly unknown due to the difficulties of obtaining experimental data. In this publication, the impingement of small isooctane droplets on a hot piston surface is studied. The emphasis was put on the image-based investigation of the process of successive impingements and its influence on secondary droplet formation. The diameter and velocity of the secondary droplets were found to depend on the wall temperature and impingement frequency. Thus, the temporal interaction has a significant influence on the secondary droplet characteristics.The physics of the impingement process of small hydrocarbon droplets is mostly unknown due to the difficulties of obtaining experimental data. In this publication, the impingement of small isooctane droplets on a hot piston surface is studied. The emphasis was put on the image-based investigation of the process of successive impingements and its influence on secondary droplet formation. The diameter and velocity of the secondary droplets were found to depend on the wall temperature and impingement frequency. Thus, the temporal interaction has a significant influence on the secondary droplet characteristics.

Plasmodium parasites are exposed to elevated fluxes of reactive oxygen species during intraerythrocytic life. The most important antioxidative systems are based on the glutathione reductases of the malarial parasite Plasmodium falciparum and the host erythrocyte. The development of menadione chemistry has led to the selection of the carboxylic acid 6-[2‘-(3‘-methyl)-1‘,4‘-naphthoquinolyl] hexanoic acid M5 as an inhibitor of the parasitic enzyme. As reported here, revisiting the mechanism of M5 action revealed an uncompetitive inhibition type with respect to both NADPH and glutathione disulfide. Masking the polarity of the acidic function of M5 by ester or amide bonds improved antiplasmodial activity. Bioisosteric replacement of the carboxylic function by tetrazole to increase bioavailability and to maintain comparable acidity led to improved antimalarial properties as well, but only with the cyanoethyl-protected tetrazoles. Using computed ab initio quantum methods, detailed analyses of the electronic profiles and the molecular properties evidenced the similarity of M5 and the bioisoteric tetrazole T4. The potential binding site of these molecules is discussed in light of the recently solved crystallographic structure of P. falciparum enzyme.

Zusammenfassung Die Brief Repeatable Battery of Neuropsychological Tests (BRB-N) ist eine bei Multipler Sklerose (MS) häufig angewandte neuropsychologische Screening-Batterie, die bislang aufgrund fehlender Normwerte kaum in der Routineversorgung, sondern fast ausschließlich in Studien verwendet wird. Anhand einer schrittweisen linearen Regressionsanalyse wurde bei 241 gesunden Probanden die Abhängigkeit der Testergebnisse der BRB-N von Alter, Geschlecht und Bildung evaluiert, die Normgrenzen festgelegt, wobei z-Werte von −1,68 und weniger als pathologisch betrachtet wurden. Jeweils eine Gruppe von Patienten mit schubförmig remittierender MS (RRMS, n=43) und sekundär progredienter MS (SPMS, n=60) wurden anhand dieser Normgrenzen hinsichtlich des Anteils kognitiv beeinträchtigter Patienten untersucht. Das Regressionsmodell erklärte 2,7–25,0% der Gesamtvarianz der Testergebnisse. Insgesamt zeigten sich 38% der RRMS- und 47% der SPMS-Patienten kognitiv beeinträchtigt, wobei im Testprofil in beiden Gruppen Konzentrations- und Aufmerksamkeitsstörungen, in der SPMS-Gruppe zusätzlich Gedächtnisstörungen dominierten. Die Häufigkeit kognitiver Beeinträchtigung war vereinbar mit Angaben in der Literatur.

A correlation in terms of temperature and molar volume is recommended for the viscosity of liquid cyclopentane as a reference for low-temperature, high-pressure viscosity measurements. The temperature range covered is from 220 to 310 K and the pressure range from atmospheric up to 25 MPa. The standard deviation of the proposed correlation, within a 95% confidence limit, is 1%.

Zusammenfassung: Einleitung. Die Vermeidung einer permanenten Kolostomie durch sphinktererhaltende Operationsverfahren ist ein Hauptziel der Rektumkarzinomchirurgie. In der Literatur werden sehr unterschiedliche Rektumexstirpationsraten angegeben. Material/Methode. Die Untersuchung wurde innerhalb einer prospektiven Multicenterstudie zur Erfassung der Qualitt der Diagnostik und Therapie des kolorektalen Karzinoms an 282 Kliniken innerhalb des Jahres 2000 durchgefhrt. In dieser Untersuchung wurden 9.477 Patienten erfasst, 3.402 mit einem Rektumkarzinom und 6.075 mit einem Kolonkarzinom. Ergebnisse. Es wurden 866 Rektumexstirpationen durchgefhrt.Dies entspricht einer Rektumexstirpationsrate von 27,4%; 30,4% aller Mnner mit einem Rektumkarzinom und 23,0% aller Frauen wurden einer Rektumexstirpation unterzogen; 8,3% aller Tumore, die einer Rektumexstirpation zugefhrt wurden,hatten eine pT4-Kategorie und 57,5% eine pT3-Kategorie.Die Rektumexstirpationsraten, adaptiert an die Hhenlokalisation des Tumors,d.h.Abstand des aboralen Tumorrandes von der Anokutanlinie, betrugen: <4 cm ab ACL – 84,6%, 4–7,9 cm – 43,9%,8–11,9 cm – 5,8% und 12–16 – – 0,5%.Intraoperative Komplikationen traten in 11,8%, spezifische postoperative Komplikationen in 33,1% und allgemeine postoperative Komplikationen in 27,4% auf.Die postoperative Letalitt betrug 2,8%.Die postoperative Verweildauer lag bei 21,7 Tagen.Die logistische Regression zeigte den BMI,das Geschlecht, die Hhe des Karzinoms und die T-Kategorie als unabhngige Einflussfaktoren auf die Rektumexstirpationsrate. Diskussion. Trotz insgesamt rcklufiger Hufigkeit spielt die abdominoperineale Rektumexstirpation in Deutschland auch weiterhin eine bedeutende Rolle bei der operativen Therapie tief sitzender Rektumkarzinome im klinischen Alltag. Es bleibt eine individuelle Entscheidung bei jedem einzelnen Patienten, ob eine Sphinktererhaltung von Seiten des Tumors und des Patienten machbar ist oder ob eine Exstirpation erforderlich erscheint. Die generelle Vorgabe einer Rektumexstirpationsrate bei einem unselektionierten Krankengut sollte nach den Ergebnissen der vorliegenden Untersuchung sehr kritisch gesehen werden.

Abstract:  For a liquid globule, partly captured in spherical caps of different meridian angles the thermo-capillary flow has been determined due to the change of temperature on the liquid surface. The variation of the applied temperature on the liquid surface causes a variation of the surface tension and therefore a tangential force moving from warm to cold. The streamlines are presented for linear and quadratic temperature distribution on the liquid surface. As the cap angle α increases the center of the ring vortex moves down and towards the free liquid surface. In addition the flow exhibits with increasing magnitude of cap coverage a reduced velocity distribution. For a quadratic temperature distribution the existence of two opposite vortex rings are shown for α<π/2. The upper vortex ring disappears as α becomes larger than π/2. In addition we notice the shift of the vortex core towards the free surface and bottom of the drop.

Abstract:  The axisymmetric fundamental natural damped frequency of the free surface in a slowly rotating cylindrical container is determined for incompressible viscous liquid. It was found that with increasing liquid height ratio h/a oscillation frequencies and decay magnitude both exhibit increased values. The influence of the surface tension parameter σ*=σa/ϱν2 shows for increasing magnitude increasing oscillation frequencies and decreasing decay magnitudes. For increasing Bond number Bo the oscillation frequency increases while the decay magnitude decreases. The effect of increasing the spin parameter ω0=Ω0 a 2/ν is manifested by an increase of the oscillation frequency and decay magnitude, i.e. for faster spin a liquid disturbance decays faster with larger oscillation frequency.

Das subunguale Chondrom ist eine Sonderform des periostalen Chondroms, das hauptsächlich in den kurzen Röhrenknochen der Hände und Füße vorkommt. Maligne Entartung ist selten, aber beschrieben worden. Die histologische Abgrenzung vom gut differenzierten Chondrosarkom kann Schwierigkeiten bereiten. Wir berichten über den Fall einer 14-jährigen Patientin mit einjährigem Krankheitsverlauf eines subungualen Chondroms an der vierten Fußzehe. Sie wurde mit gutem Erfolg operativ behandelt. Subungual chondroma is a rare occurrence of periosteal chondroma, which mainly affects short tubular bones of the hands and feet. Transformation towards malignancy has been described in a small number of cases; however histologic diagnosis can prove to be difficult, especially with regard to well differentiated chondrosarcoma. We report the case of a 14 year old girl with a one year history of subungual chondroma of the fourth toe with good clinical response to surgical removal.