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Individuals with minor ischaemic stroke and intracranial occlusion are at increased risk of poor outcomes. Intravenous thrombolysis with tenecteplase might improve outcomes in this population. We aimed to test the superiority of intravenous tenecteplase over non-thrombolytic standard of care in patients with minor ischaemic stroke and intracranial occlusion or focal perfusion abnormality.

ABSTRACT This paper presents an experimental analysis of the impact of salt pore clogging on the hygric properties of bricks, with a focus on CaS[0.sub.4]*2[H.sub.2]0 and NaCl. The study includes [...]

ABSTRACT: This study presents experimental analysis and numerical modeling of hygroscopic moisture buffering by paper and books. First, a literature review of moisture transport properties of paper is presented. Experimental [...]

By the end of the 1990s, the global peak of energy supply from oil and gas deposits had already been reached. Since then, there has been a clear trend towards the development of new, more sustainable ways of supplying energy. To realize this reduction, a holistic and rapid restructuring of the energy supply towards CO2-free and renewable energy production, storage and processing across all areas of life is necessary. The development and implementation of a functioning hydrogen economy can be crucial with respect to the goal of climate neutrality. The scale-up and commercialization of technologies for the cost-effective production and use of hydrogen carry significant importance. Accordingly, innovative production technologies and process chains must be developed to be able to manufacture fuel cells reliably in high volumes and at optimized costs. In this context, BPPs in the PEM-FC are responsible for about 80 % of the total weight, just over 50 % of the system volume, and up to 40 % of the total cost. Current research approaches in the field of BPP forming focus mainly on the optimization of a pre-selected production technology. Thereby, the possibility of combining different forming technologies to represent a holistic process chain is mostly disregarded. This research gap is to be closed by the developments within the scope of this work. The bipolar plate is not to be regarded as a coherent component, but as a composition of different geometric features.

The laser-assisted tape placement process faces thermal challenges at geometrically changing substrates. Due to changing optical conditions and thereby varying local energy absorption, local differences of the process temperature occur. These temperature inhomogeneities become even more pronounced due to restrictions with regard to machine dynamics. In particular, strong directional changes, which are necessary e.g. for small machining radii, result in the relative speed between workpiece and laser beam not being constant. The use of vertical-cavity surface-emitting lasers (short: VCSEL) as adaptive heat sources could improve the temperature control especially by use of application adapted intensity distributions that can be calculated through inverse simulations.

Depression is the most prevalent psychiatric disorder with a complex and elusive etiology that is moderately heritable. Identification of genes would greatly facilitate the elucidation of the biological mechanisms underlying depression, however, its complex etiology has proved to be a major bottleneck in the identification of its genetic risk factors, especially in genome-wide association-like studies. In this study, we exploit the properties of a genetic isolate and its family-based structure to explore whether relatively rare exonic variants influence the burden of depressive symptoms in families. Using a multistep approach involving linkage and haplotype analyses followed by exome sequencing in the Erasmus Rucphen Family (ERF) study, we identified a rare (minor allele frequency (MAF)=1%) missense c.1114C>T mutation (rs115482041) in the RCL1 gene segregating with depression across multiple generations. Rs115482041 showed significant association with depressive symptoms (N=2393, βT-allele=2.33, P-value=1 × 10−4) and explained 2.9% of the estimated genetic variance of depressive symptoms (22%) in ERF. Despite being twice as rare (MAF<0.5%), c.1114C>T showed similar effect and significant association with depressive symptoms in samples from the independent population-based Rotterdam study (N=1604, βT-allele=3.60, P-value=3 × 10−2). A comparison of RCL1 expression in human and mouse brain revealed a striking co-localization of RCL1 with the layer 1 interlaminar subclass of astrocytes found exclusively in higher-order primates. Our findings identify RCL1 as a novel candidate gene for depression and offer insights into mechanisms through which RCL1 may be relevant for depression.

Normothermic ex vivoliver perfusion (NEVLP) offers the potential to optimize graft function prior to liver transplantation (LT). Hepatitis C virus (HCV) is dependent on the presence of miRNA(microRNA)‐122. Miravirsen, a locked‐nucleic acid oligonucleotide, sequesters miR‐122 and inhibits HCVreplication. The aim of this study was to assess the efficacy of delivering miravirsen during NEVLPto inhibit miR‐122 function in a pig LTmodel. Pig livers were treated with miravirsen during NEVLPor cold storage (CS). Miravirsen absorption, miR‐122 sequestration, and miR‐122 target gene derepression were determined before and after LT. The effect of miravirsen treatment on HCVinfection of hepatoma cells was also assessed. NEVLPimproved miravirsen uptake versus CS. Significant miR‐122 sequestration and miR‐122 target gene derepression were seen with NEVLPbut not with CS. In vitrodata confirmed miravirsen suppression of HCVreplication after established infection and prevented HCVinfection with pretreatment of cells, analogous to the pretreatment of grafts in the transplant setting. In conclusion, miravirsen delivery during NEVLPis a potential strategy to prevent HCVreinfection after LT. This is the first large‐animal study to provide “proof of concept” for using NEVLPto modify and optimize liver grafts for transplantation. Miravirsen delivery during normothermic ex vivoliver perfusion is a potential strategy to prevent hepatitis C reinfection after liver transplantation and, most importantly, provides a proof‐of‐concept for ex vivoliver graft modification.

Background and aimThe importance of mechanical thrombectomy in acute stroke treatment has grown over recent years. Mechanical thrombectomy comprises many different techniques. Technical improvements in the catheter material have led to the development of large-bore distal access catheters which can enter tortuous intracranial vessels. This has promising applications for endovascular stroke treatment. This study evaluated the safety and success rate of ultra-distal access of the middle cerebral artery (MCA) M1 segment with the 5 Fr Navien 58 distal access catheter in the treatment of acute stroke in combination with stent retrievers.MethodsWe retrospectively analyzed 81 patients with an acute stroke of the anterior circulation in whom ultra-distal access to the M1 segment was carried out using the Navien 58 catheter with an anchoring technique with a stent retriever for mechanical thrombectomy. Technical complications, success rates of catheter placement, success rates of thrombectomy using the modified Thrombolysis In Cerebral Infarction (mTICI) score, and the procedure times were evaluated.ResultsUltra-distal access with the Navien 58 was successful in 75% (61/81) of cases. Recanalization success with a mTICI score of 2b and better was achieved in 83% overall (67/81), in 90% (55/61) of cases with successful ultra-distal access and in 60% (12/20) of cases without ultra-distal access. No severe adverse effects such as dissections or perforations occurred as a result of the ultra-distal catheter placement in the M1 segment. In 4% (3/81) of the cases a reversible MCA vasospasm occurred.ConclusionsUltra-distal placement of the Navien 58 distal access catheter into the M1 segment in acute anterior circulation stroke can be achieved consistently, is safe in practice, and results in good recanalization success rates.

Automated laser assisted tape placement is an additive manufacturing technology for the production of composite parts. Composite parts are common in various markets. Especially the automotive sector has a demand for lighter and stronger materials. The combination of standard sheet metal materials and fiber reinforced plastics promises to deliver enhanced properties and performances over the separate materials themselves. This multi-material combination is classically done with mechanical connections. This paper addresses a direct in-situ approach of putting carbon fiber reinforced thermoplastic tapes directly onto pre-structured sheet metal parts and shows the prerequisites needed for achieving a consolidation between both materials.

In the nontransplant setting diabetes mellitus is a risk factor for disease progression in patients with chronic hepatitis C virus (HCV) infection. The impact of early insulin resistance on the development of advanced fibrosis, even in the absence of clinically apparent diabetes mellitus, is not known.

Magnetic resonance elastography (MRE) is an emerging technique capable of measuring the shear modulus of tissue. A suspected tumour can be identified by comparing its properties with those of tissues surrounding it; this can be achieved even in deep-lying areas as long as mechanical excitation is possible. This would allow non-invasive methods for cancer-related diagnosis in areas not accessible with conventional palpation. An actuating mechanism is required to generate the necessary tissue displacements directly on the patient in the scanner and three different approaches, in terms of actuator action and position, exist to derive stiffness measurements. However, the magnetic resonance (MR) environment places considerable constraints on the design of such devices, such as the possibility of mutual interference between electrical components, the scanner field, and radio frequency pulses, and the physical space restrictions of the scanner bore. This paper presents a review of the current solutions that have been developed for MRE devices giving particular consideration to the design criteria including the required vibration frequency and amplitude in different applications, the issue of MR compatibility, actuation principles, design complexity, and scanner synchronization issues. The future challenges in this field are also described.

The exact experimental determination of the pressure dependence of the explosion limits of hydrogen/oxygen mixtures at 20 °C and 80 °C was investigated. The anomaly in the pressure dependence of hydrogen explosion limits (decrease of the upper explosion limit with increase in pressure), known for hydrogen/air mixtures, could be confirmed for hydrogen/oxygen mixtures. Furthermore it was shown that the impurities in the product gases of the electrolyzer did not exceed 50 % of the lower explosion level in any case.

In the last decade, microsystem engineering has rapidly developed. Nowadays microsystems have a very broad scope of applications, which range from electronics and aerospace to chemistry, optics, biology and medicine. Within this framework, the joining technique plays a crucial role. Therefore the development of new concepts for joining hybrid microstructures is one of the main tasks within the collaborative research center, assembly of hybrid microsystems. Active soldering and transient liquid phase (TLP) bonding processes are two innovative and trend-setting technologies in the field of joining dissimilar materials and have been specifically adapted to the requirements of the microsystems.

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Poly(propylene imine) (PPI) dendrimers of generations 1−5 have been derivatized with dialkyl sulfide chains. On water, these dendrimers form stable LB films with densely packed alkyl chains pointing to the air and cores exposed to the aqueous solution. Self-assembly of the same dendrimers from solution onto a gold surface leads to a flattened orientation of the molecules on the surface, as shown by high contact angle hystereses, high electrochemical capacitances, and low charge transfer resistances. X-ray photoelectron spectroscopy data indicate that the formation of the flattened structure can be attributed to adsorption to the gold surface of not only part of the sulfide moieties in the alkyl chains, but also part of the tertiary amines in the core. The electrochemically determined surface coverages of ferrocene-modified dendritic wedges (with similar molecular structures as those of the dialkyl sulfide PPI dendrimers) confirm the proposed flattened, surface-spread dendritic structure. In contrast, LB films of the sulfide PPI dendrimers that were transferred onto gold appear to largely remain their original, densely packed state, as for these films smaller contact angle hystereses and higher charge transfer resistances are measured than those observed for the monolayers prepared by self-assembly from solution. Additionally, the electrochemical capacitances of the transferred LB films point to a layer thickness comparable to the thickness of a densely packed didecylsulfide monolayer. The results in this study demonstrate that different surface architectures can be prepared of the same compounds by solely varying the preparation procedure.

Abstract We studied the course of serum bile acids to investigate its reliability in the diagnosis of acute rejection after liver transplantation in relation to pathohistological findings. Serum bile acid concentration, bilirubin and transaminases were measured in 41 patients who underwent liver transplantation. Their course was correlated to liver biopsy. Group I (n= 19) patients were without acute rejection, whereas group II (n= 22) patients showed acute rejection. Bile acid concentrations in group II showed a statistically highly significant (P< 0.001) threefold increase 3 days prior to biopsy. Successful antirejection treatment was correlated with a statistically significant (P= 0.008) decrease of serum bile acid 1 day after initiation of therapy. Patients without acute rejection showed a baseline bile acid concentration at the time of biopsy. Bilirubin and transaminases did not show any statistically significant correlation to acute rejection.

BACKGROUND: Malignancy, hypercoagulability, and conditions leading to decreased portal flow have been reported to contribute to the aetiology of extrahepatic portal vein thrombosis (EPVT). Mortality of patients with EPVT may be associated with these concurrent medical conditions or with manifestations of portal hypertension, such as variceal haemorrhage. PATIENTS AND METHODS: To determine which variables have prognostic significance with respect to survival, we performed a retrospective study of 172 adult EPVT patients who were followed over the period 1984-1997 in eight university hospitals. RESULTS: Mean follow up was 3.9 years (range 0.1-13.1). Overall survival was 70% (95% confidence interval (CI) 62-76%) at one year, 61% (95% CI, 52-67%) at five years, and 54% (95% CI, 45-62%) at 10 years. The one, five, and 10 year survival rates in the absence of cancer, cirrhosis, and mesenteric vein thrombosis were 95% (95% CI 87-98%), 89% (95% CI 78-94%), and 81% (95% CI 67-89%), respectively (n=83). Variables at diagnosis associated with reduced survival according to multivariate analysis were advanced age, malignancy, cirrhosis, mesenteric vein thrombosis, absence of abdominal inflammation, and serum levels of aminotransferase and albumin. The presence of variceal haemorrhage and myeloproliferative disorders did not influence survival. Only four patients died due to variceal haemorrhage and one due to complications of a portosystemic shunt procedure. CONCLUSION: We conclude that mortality among patients with EPVT is related primarily to concurrent disorders leading to EPVT and not to complications of portal hypertension.

Abstract.: We studied the course of serum bile acids to investigate its reliability in the diagnosis of acute rejection after liver transplantation in relation to pathohistological findings. Serum bile acid concentration, bilirubin and transaminases were measured in 41 patients who underwent liver transplantation. Their course was correlated to liver biopsy. Group I (n = 19) patients were without acute rejection, whereas group II (n = 22) patients showed acute rejection. Bile acid concentrations in group II showed a statistically highly significant (P≤ 0.001) threefold increase 3 days prior to biopsy. Successful antirejection treatment was correlated with a statistically significant (P = 0.008) decrease of serum bile acid 1 day after initiation of therapy. Patients without acute rejection showed a baseline bile acid concentration at the time of biopsy. Bilirubin and transaminases did not show any statistically significant correlation to acute rejection. Infection did not lead to a significant bile acid increase. Our study shows that serum bile acids monitored after liver transplantation can easily be used to detect acute rejection and at the same time they reflect the success of antirejection therapy.

The new casting-rolling plant of Thyssen Krupp Stahl AG is in operation since April 1999. Differences in comparison with other CSP plants are described. The production results at this time are explained together with the range of steel grades and the achieved dimensions. Differences with respect to conventional hot rolled strip are shown in surface quality as well as in mechanical properties and in dimensional tolerances.

The synthesis of a new processable alternating conjugated copolymer consisting of N-dodecylpyrrole and 2,1,3-benzothiadiazole repeat units (PDPB) is accomplished via condensation copolymerization of 2,5-bis(trimethylstannyl)-N-dodecylpyrrole and 4,7-dibromo-2,1,3-benzothiadiazole under the Stille coupling conditions using Pd(PPh3)2Cl2 as a catalyst in dry THF. MALDI-TOF mass spectrometry revealed a perfect alternation of monomer units in PDPB and enabled the identification of hydrogen, bromine, and methyl end groups. As a consequence of its semiamphiphilic nature, PDPB can form stable and transferable monomolecular Langmuir films at the air−water interface. The interaction between the electron-releasing N-dodecylpyrrole and electron-withdrawing 2,1,3-benzothiadiazole units in PDPB results in an optical band gap of 2.03 eV and a red emission. Photoinduced absorption (PIA) and photoluminescence (PL) spectroscopy revealed that in a composite film of PDPB with a methanofullerene (PCBM) as acceptor the fluorescence and the intersystem crossing of the pristine polymer are strongly quenched. Bulk heterojunction photovoltaic cells of PDPB and PCBM (1:3 by weight) have been prepared and demonstrate that in such devices this quenching involves generation of charge carriers.

A complete set of data for the decay scheme of a radionuclide requires knowledge of the emission probabilities of X-rays and Auger electrons. If adopted sets of transition probabilities for the transitions of the decay scheme and atomic shell data (such as fluorescence yields and relative emission probabilities) are available, the emission probabilities of the X-rays and Auger electrons can be calculated from these data. Only data calculated in this way are consistent with the adopted input data and can be compared with measured data. Conclusions can be drawn with respect to the internal consistency of the data sets by comparing the measured and calculated data. Hence, the EMISSION program has been developed and tested to calculate X-ray and Auger electron emission probabilities along with their error propagation.

A method is described for determining the depth distribution of the radioactive substance of alpha-emitting nuclides in a wide-area reference source. The method combines measurements and calculations. In the experimental part, the energy spectrum of the source is measured by means of an alpha spectrometer. The energy spectrum is then modelled by the Monte Carlo method, taking into account energy loss of alpha particles in the source matrix, energy-loss straggling and the parameters of the spectrometer. Additional parameters for the characterization of reference sources are derived from the integral of the depth distribution. The investigations prove that the production process of commercial sources can be controlled in such a way that more than 90% of the radioactive material is implanted in the top layer of 5 μm thickness of an aluminum foil.

Aluminium–aluminiumoxide–silver tunnel junctions allow to measure light emission by hot electrons and internal photoemission. Adsorption of potassium or oxygen on the silver electrode increases or quenches the light emission considerably. The light intensity increases at negative surface charge on the silver electrode and is suppressed at positive surface charge. Surprisingly, the light emission by hot electrons within the optical skin depth is negligible. The observed intensity is assigned to electron–photon coupling at the surface, especially to inverse photoemission by hot electrons via the time inverted threshold effect postulated by A. Liebsch. This is not in contradiction to time resolved two photon photoemission experiments. Internal photoemission experiments corroborate this interpretation.

We present a field-theoretic renormalization-group study for the critical behavior of a uniformly driven diffusive system with quenched disorder, which is modeled by different kinds of potential barriers between sites. Due to their symmetry properties, these different realizations of the random potential barriers lead to three different models for the phase transition to transverse order and to one model for the phase transition to longitudinal order all belonging to distinct universality classes. In these four models, which have different upper critical dimensions dc, we find the critical scaling behavior of the vertex functions in spatial dimensions d

Integrin beta4 null mice exhibit extensive epidermal detachment, reminiscent of the human skin blistering disease junctional epidermolysis bullosa associated with pyloric atresia. Hemidesmosomes, the stable adhesion structures of squamous epithelia, are not formed in the absence of alpha6beta4. Null mutant mice die shortly after birth, but apart from their striking epithelial phenotype, no obvious developmental defects have been observed. To elucidate the cause of death in these mice, we generated transgenic mice with a heterologous construct consisting of the squamous epithelial-specific keratin-5 promoter and a human integrin beta4 subunit cDNA. The transgene was not expressed in the presence of endogenous beta4, probably as a result of competition for a limited pool of alpha6 subunits. In a beta4 null background, however, the transgene was expressed, and its expression pattern followed that of squamous epithelial-specific keratins. These rescued pups appeared healthy and ultrastructural analysis revealed that the interspecies heterodimer alpha6(mouse)/beta4(human) was sufficient to trigger the assembly of hemidesmosomes. After a variable period of up to 48 hours after birth these animals began to exhibit haemorrhages at the plantar and palmar areas. We observed the formation of small blisters and found that the transgene was not detectably expressed in this region, which is devoid of hair follicles. The rescued neonates became increasingly cyanotic and died soon after the onset of this phenomenon. We performed a developmental study of the expression of beta4 in the complete respiratory tract, but we found no correlation between the spatiotemporal distribution of beta4 and the onset of the respiratory insufficiency. It became clear, however, that there was a gradual detachment of squamous epithelia in the oral and nasal cavities which led to obstruction of the respiratory tract, suggesting that in beta4 null and rescued mice, neonatal death was a direct consequence of decreased adhesion properties of hairless squamous epithelia, rather than a developmental defect of the lungs.

The diffusion of hard-core particles subject to a global bias is described by a nonlinear, anisotropic generalization of the diffusion equation with conserved, local noise. Using renormalization group techniques, we analyze the effect of an additional noise term, with spatially long-ranged correlations, on the long-time, long-wavelength behavior of this model. Above an upper critical dimension dLR, the long-ranged noise is always relevant. In contrast, for d

In the bloodstream of the mammalian host, Trypanosoma brucei takes up host transferrin by means of a high‐affinity uptake system, presumably a transferrin receptor. Transferrin‐binding activity is seen in the flagellar pocket and is absent in insect form trypanosomes. By transfection we have reconstituted a transferrin‐binding complex in insect form trypanosomes. Formation of this complex requires the products of two genes that are part of a variant surface glycoprotein expression site, expression site‐associated gene (ESAG) 6 (encoding a protein with GPI‐anchor) and ESAG 7 (encoding a protein without any obvious membrane attachment). This complex can be precipitated by transferrin‐Sepharose and by an antibody directed only against the ESAG 6 protein. Transfection of ESAG 6 or 7 alone did not result in transferrin binding. In the transfected trypanosomes, the products of ESAG 6 alone and the combination of ESAG 6 and 7 did not exclusively localize to the flagellar pocket, but were present all over the surface of the trypanosome. The reconstituted transferrin‐binding complex also did not result in the uptake of transferrin. Additional proteins present in bloodstream trypanosomes, but not in sufficient amounts in insect form trypanosomes, may therefore be required for the correct routing of the transferrin‐binding complex to the flagellar pocket, and for its rapid internalization after ligand binding.