Studying Fluid Characteristics Atop Surface Patterned Membranes via Particle Image Velocimetry

Surface patterning is a recent promising approach to promote performance of pressure-driven membranes in water treatment and desalination. Nevertheless, knowledge about foulant deposition mechanisms, especially at early stage of filtration, is still lacking. The applicability of particle imaging velocimetry to study fluid characteristics atop surface patterned thin-film composite membranes was investigated at different operating conditions. This work is an important first step toward reliable understanding of the impacts of topographical membrane surface modification on hydrodynamic conditions and foulant deposition mechanisms.     

Optimized Machine Learning Algorithms for Investigating the Relationship Between Economic Development and Human Capital

Computational Economics - In Economic Development, human capital was previously seen as production factors but gradually evolved into endogenous growth theories. Most of the previous studies have...     

Systematic Review: Targeted Molecular Imaging of Angiogenesis and Its Mediators in Rheumatoid Arthritis

Extensive angiogenesis is a characteristic feature in the synovial tissue of rheumatoid arthritis (RA) from a very early stage of the disease onward and constitutes a crucial event for the development of the proliferative synovium. This process is markedly intensified in patients with prolonged disease duration, high disease activity, disease severity, and significant inflammatory cell infiltration. Angiogenesis is therefore an interesting target for the development of new therapeutic approaches as well as disease monitoring strategies in RA. To this end, nuclear imaging modalities represent valuable non-invasive tools that can selectively target molecular markers of angiogenesis and accurately and quantitatively track molecular changes in multiple joints simultaneously. This systematic review summarizes the imaging markers used for single photon emission computed tomography (SPECT) and/or positron emission tomography (PET) approaches, targeting pathways and mediators involved in synovial neo-angiogenesis in RA.     

Site-Directed Immobilization of an Engineered Bone Morphogenetic Protein 2 (BMP2) Variant to Collagen-Based Microspheres Induces Bone Formation In Vivo

For the treatment of large bone defects, the commonly used technique of autologous bone grafting presents several drawbacks and limitations. With the discovery of the bone-inducing capabilities of bone morphogenetic protein 2 (BMP2), several delivery techniques were developed and translated to clinical applications. Implantation of scaffolds containing adsorbed BMP2 showed promising results. However, off-label use of this protein-scaffold combination caused severe complications due to an uncontrolled release of the growth factor, which has to be applied in supraphysiological doses in order to induce bone formation. Here, we propose an alternative strategy that focuses on the covalent immobilization of an engineered BMP2 variant to biocompatible scaffolds. The new BMP2 variant harbors an artificial amino acid with a specific functional group, allowing a site-directed covalent scaffold functionalization. The introduced artificial amino acid does not alter BMP2′s bioactivity in vitro. When applied in vivo, the covalently coupled BMP2 variant induces the formation of bone tissue characterized by a structurally different morphology compared to that induced by the same scaffold containing ab-/adsorbed wild-type BMP2. Our results clearly show that this innovative technique comprises translational potential for the development of novel osteoinductive materials, improving safety for patients and reducing costs.     

Untersuchungen zum Transfer pharmakologisch wirksamer Substanzen aus der Nutztierhaltung in Porree und Weißkohl

Investigation on the transfer of pharmacologically active substances used in animal husbandry into leek and cabbage. The potential of leek and cabbage for uptake of highly prescribed veterinary drugs (antibiotics) was tested in hydroponically grown plants. For this purpose the antibiotics sulfadiazine (SFD), enrofloxacine (ENR), tetracycline (TC), chlortetracycline (CTC) and monensine (MON) were chosen. A further aim was to gain data on the situation of vegetables grown in agricultural practise with regard to antibiotic residues. The evident effects of the antibiotics on plants grown hydroponically (each antibiotic was administered at 5 μmol/l nutrient solution) were greatly different: With regard to leek there were no visible effects (MON, SFD), a weak bleaching of the younger leaf sections (CTC), and strong effects of ENR. The (phytotoxic) effects of antibiotics on cabbage were much more distinct. CTC caused a yellowing of the plant vasculature in cabbage. MON induced lesions on some leaves and finally led to leaf wilting. With administration of ENR a nearly complete bleaching of young leaves was observed. Using LC-MS/MS-methods (low-resolution and high-resolution MS) the administered antibiotics, as well as conversion products and metabolites, were separately identified and quantified in various organs of leek (roots, young and old sections of leaves) and cabbage (roots, stalks, young and old leaves). Depending on the type of antibiotic, vegetable species, and plant organ, the detected concentrations of antibiotic residues comprised several orders of magnitude ranging from μg/kg to mg/kg of fresh weight (fw). The highest concentrations of antibiotics were found in roots of both vegetable species: CTC and TC were detected at approximately 10 mg/kg fw in cabbage roots and at approximately 20 mg/kg fw in leek roots and ENR was determined at approximately 12 mg/kg fw in cabbage roots. Low amounts of ENR were metabolised to ciprofloxacine (CIP). ENR occurred at similar concentrations of approximately 7 mg/kg fw in roots and old leaves of cabbage, indicating a high transport rate of this antibiotic in the cabbage plant. In stalks, young and old leaves of cabbage and in young and old leaf sections of leek all administered antibiotics were detected. Within these antibiotics, ENR and CTC and their conversion products, e. g. demeclocycline (DMC) and TC, occurred at the highest concentrations. SFD and MON were found in considerably lower concentrations (<100 μg/kg fw). The results of our experiments in hydroponic cultures, using defined concentrations of antibiotics in the nutrient solution, evidently demonstrate that cabbage and leek have a very high potential for uptake of a number of veterinary antibiotic drugs, especially for tetracycline and ENR.     

Preparation of Lead Zirconate Titanate (Pb(Zr0.52Ti0.48)O3) by Homogeneous Precipitation and Calcination

Preparation of phase-pure PZT (Pb(Zr_0.52Ti_0.48)O₃) powders was achieved, in the presence of urea (CH₄N₂O), by homogeneous precipitation. Aqueous solutions of PbCl₂, ZrOCl₂·8H₂O, and TiCl₄ were used as the starting materials in the synthesis of phase-pure PZT powders. Phase evolution behavior of precursor powders was studied by powder X-ray diffraction (XRD) in air, over the temperature range of 90° to 750°C. The morphology of the formed powders was studied by scanning electron microscopy (SEM). Semiquantitative chemical analyses of the samples were performed by energy-dispersive X-ray spectroscopy (EDXS).     

Phase Relations in the System Al2O3─Ce2Si2O7 in the Temperature Range 900° to 1925°C in Inert Atmosphere

Equilibrium relationships in the system Al₂O₃-Ce₂Si₂O₇ in inert atmosphere have been investigated in the temperature range 900° to 1925°C. A simple eutectic reaction was found at 1375°C and 51 mol% Ce₂Si₂O₇. A high-low polymorphic transformation in Ce₂Si₂O₇ was observed at 1274°C. New XRD patterns are suggested for both polymorphs of cerium pyrosilicate. The melting point of Ce₂Si₂O₇ was found to be 1788°C. A value for ΔH°_m,Ce2Si2O7 of 36.81 kJ/mol was calculated from the initial slope of the experimentally determined liquidus in equilibrium with the pyrosilicate phase.     

Microbial reductive transformation of pentachloronitrobenzene under methanogenic conditions

The reductive transformation of pentachloronitrobenzene (PCNB), an organochlorine fungicide, was investigated with a mixed, methanogenic culture developed from a contaminated estuarine sediment. Batch assays performed with this enrichment culture resulted in the biotransformation of PCNB to pentachloroaniline (PCA), which was then sequentially dechlorinated as follows: PCA --> 2,3,4,5- and 2,3,5,6-tetrachloroaniline (TeCA) --> 2,4,5- and 2,3,5-trichloroaniline (TrCA) --> 2,4-, 2,5-, and 3,5-dichloroaniline (DCA) --> 3- and 4-chloroaniline (CA) (low levels). Glucose fermentation, methanogenesis, and dechlorination were not inhibited at an initial PCNB concentration up to 40 microM, which is 27 times higher than its aqueous solubility. The addition of 25 mM 2-bromoethanesulfonate (BES) to the PCNB-amended culture resulted in the complete inhibition of methanogenesis, but the biotransformation of PCNB to PCA and its sequential dechlorination pathway were not affected. The addition of sodium azide (200 mg/L) to the PCNB-amended culture resulted in complete inhibition of methanogenesis, but did not inhibit the transformation of PCNB to PCA; however, PCA dechlorination was not observed. PCNB was also abiotically transformed to PCA in autoclaved culture media but at much lower rates as compared to the biotic assays. In contrast, the rate of PCNB to PCA transformation in autoclaved culture controls was similar to the rates observed in the azide-amended culture and the active enrichment culture, indicating that biotically derived reductants facilitated the observed transformation of PCNB to PCA. Dechlorination of PCA was not observed in any of the abiotic controls. These findings have significant environmental implications in terms of the fate and transport of PCNB, PCA, and its dechlorination products in subsurface systems.