Bioenergetic Alterations of Metabolic Redox Coenzymes as NADH,FAD and FMN by Means of Fluorescence Lifetime Imaging Techniques

Metabolic FLIM (fluorescence lifetime imaging) is used to image bioenergetic status in cells and tissue. Whereas an attribution of the fluorescence lifetime of coenzymes as an indicator for cell metabolism is mainly accepted, it is debated whether this is valid for the redox state of cells. In this regard, an innovative algorithm using the lifetime characteristics of nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD) to calculate the fluorescence lifetime induced redox ratio (FLIRR) has been reported so far. We extended the FLIRR approach and present new results, which includes FLIM data of the various enzymes, such as NAD(P)H, FAD, as well as flavin mononucleotide (FMN). Our algorithm uses a two-exponential fitting procedure for the NAD(P)H autofluorescence and a three-exponential fit of the flavin signal. By extending the FLIRR approach, we introduced FLIRR1 as protein-bound NAD(P)H related to protein-bound FAD, FLIRR2 as protein-bound NAD(P)H related to free (unbound) FAD and FLIRR3 as protein-bound NAD(P)H related to protein-bound FMN. We compared the significance of extended FLIRR to the metabolic index, defined as the ratio of protein-bound NAD(P)H to free NAD(P)H. The statistically significant difference for tumor and normal cells was found to be highest for FLIRR1.     

Embryonic Trophectoderm Secretomics Reveals Chemotactic Migration and Intercellular Communication of Endometrial and Circulating MSCs in Embryonic Implantation

Embryonic implantation is a key step in the establishment of pregnancy. In the present work, we have carried out an in-depth proteomic analysis of the secretome (extracellular vesicles and soluble proteins) of two bovine blastocysts embryonic trophectoderm primary cultures (BBT), confirming different epithelial–mesenchymal transition stages in these cells. BBT-secretomes contain early pregnancy-related proteins and angiogenic proteins both as cargo in EVs and the soluble fraction. We have demonstrated the functional transfer of protein-containing secretome between embryonic trophectoderm and maternal MSC in vitro using two BBT primary cultures eight endometrial MSC (eMSC) and five peripheral blood MSC (pbMSC) lines. We observed that eMSC and pbMSC chemotax to both the soluble fraction and EVs of the BBT secretome. In addition, in a complementary direction, we found that the pattern of expression of implantation proteins in BBT-EVs changes depending on: (i) their epithelial–mesenchymal phenotype; (ii) as a result of the uptake of eMSC- or pbMSC-EV previously stimulated or not with embryonic signals (IFN-τ); (iii) because of the stimulation with the endometrial cytokines present in the uterine fluid in the peri-implantation period.     

Energetics of Defect Fluorite and Pyrochlore Phases in Lanthanum and Gadolinium Hafnates

Aerodynamic levitation combined with laser heating was used to prepare melts in the HfO₂–La₂O₃ (–Gd₂O₃) systems. All melts crystallized upon quenching in oxygen. Hf₂La₂O₇ pyrochlore and Gd_0.5Hf_0.5O_1.75 fluorite phases were identified. Gd_0.5Hf_0.5O_1.75 fluorite was transformed into the pyrochlore structure by annealing at 1450°C. Pyrochlore that crystallized from HfO₂- La₂O₃ melts contained 31.6–34.2 mol% La₂O₃. The unit cell parameter increased linearly with La content from 10.736 to 10.789 Å. Drop solution calorimetric experiments were performed in 3Na₂O·4MoO₃ melt at 702°C. The enthalpies of formation from the oxides for pyrochlore phases are −107.0±5.0 kJ/mol for Hf₂La₂O₇ and −48.8±4.7 kJ/mol for Hf₂Gd₂O₇. The enthalpy of the pyrochlore–fluorite phase transition in Hf₂Gd₂O₇ is 23.6±3.1 kJ/mol.     

Regional mass flux balancing for controlling gentle soil remediation operations

Extraction of heavy metals by accumulating plants is a method which is currently in development for the "gentle" remediation of contaminated agricultural soils (phytoremediation, see [2]). Areal contaminant mass flux balances are basic criteria for the design of such remediations and their control. A framework for the integration of contaminant balances relating the field scale of remediation with the regional scale of soil monitoring networks is provided by the recently developed method PROTERRA [3]. The objective of the study presented in this paper was to test the suitability of PROTERRA for planning and monitoring gentle soil remediations. For this purpose we applied the PROTERRA method to the contaminated agricultural land in and around Dornach, Switzerland, to assess copper flux balances.The calculations showed that atmospheric deposition and the application of pesticides and manure are important pathways for the inputs of copper. The copper export with a special maize cultivar accumulating heavy metals would be about three times higher than the average metal export with crops. A moderate increase of sewage sludge application would lead to a substantial increase of the copper input. Decisions to remediate the soil should take the uncertainty of mass flux balances both on field scale as well as on regional scale into account. Therefore, an important need of further development of the PROTERRA method is the integration of uncertainty analysis on both scales.     

The part of the private sector in global water planning: the role of desalination

Water is the key to further development. The private sector is already playing a major role in looking into alternatives for a balanced water supply situation with the help of advanced technologies. We were generously given many Gardens of Eden, but only a few will survive into the next century. A worldwide campaign is necessary to show the scarcity of water. The United Nations Habitat II Conference in Istanbul, June 3–14, 1996, and the preceding IDA World Conference in Abu Dhabi on Desalination and Water Sciences, 18–24 November, 1995, are the immediate platforms on which international institutions and multilateral development banks can discuss this topic and help formulate an agenda for the next century.     

Crystal Chemistry and Phase Transitions in Substituted Pollucites along the CsAlSi2O6-CsTiSi2O6.5 Join: A Powder Synchrotron X-ray Diffractometry Study

The crystal structures for a suite of substituted pollucites with the compositions CsTi _x Al_{1– x} Si₂O_{6+0.5 x} , 0 ≤ x ≤ 1, have been determined from Rietveld analysis of powder synchrotron XRD data. Our results indicate that the pollucite end member (CsAlSi₂O₆) has a tetragonal structure (space group I 4₁/ a ), whereas all other compositions are cubic (space group Ia 3 d ). The increased symmetry for the titanium-substituted structures is presumably due to the incorporation of additional O²⁻ anions (needed for compensating the charge imbalance between Ti⁴⁺ and Al³⁺), which effectively holds open the expanded cubic framework. In situ cooling experiments of the substituted phase CsTi_0.1Al_0.9Si₂O_6.05 reveal a displacive transformation to the tetragonal structure at ∼230 K. This transformation is tricritical in nature and is analogous to the tetragonal-to-cubic transition in pollucite on heating.     

Electrodialytic extraction of Cu,Pb and Cl from municipal solid waste incineration fly ash suspended in water

The possibility of using fly ash from municipal solid waste incineration (MSWI) in, for example, concrete is considered. MSWI fly ash, however, has too high a concentration of heavy metals, which may cause leaching problems during use or problems with waste handling at the end of the lifetime of the concrete. The Cl content in MSWI fly ash is also too high and will cause corrosion problems in reinforced concrete. The possibility of removing some of the unwanted heavy metals (Cu and Pb) together with Cl from an MSWI fly ash suspended in water using an electrodialytic separation method was investigated. The removal of Pb and Cu was found to be highly pH dependent and the highest contents removed were 41 and 90%, respectively. The Cu concentration of the ash decreased from 2200 to 860 mg kg^?1 but the Pb concentration increased from 8560 to 16 800 mg kg^?1, showing that Pb is mainly found in the ash fraction that is least soluble. Hence electrodialytic treatment of the ash suspended in water is not a solution to improve the ash quality in terms of Pb. The water‐soluble Cl content per unit weight of the original ash was 12.4%. The removal of water‐soluble Cl was efficient and >98% of Cl was removed (calculated on the basis of mean initial and final concentrations). This result indicates that electrodialytic extraction may be a method that can be used for the removal of Cl from ash prior to its utilization in concrete. Copyright © 2006 Society of Chemical Industry     

Effect of ultrasound on thermoset polyurethane: NMR relaxation and diffusion measurements

Recycling of rubber-based materials is of increasing industrial environmental importance. In order to characterize the effect of ultrasound on polymer networks, nuclear magnetic resonance (NMR) relaxation and pulsed-gradient diffusion measurements were made at 70.5 °C in polyurethane rubber (PUR) and foam after subsequent treatment by intense ultrasound. The proton transverse relaxation decay was analyzed in terms of molecular and segmental mobilities of all motional species, a chemical and physical network as well as diffusing sol. The diffusivity spectrum, measurable in foams, reflected the changing molecular weight distribution of low-molecular weight sol and oligomers. It was observed that the effect of ultrasound was less pronounced in PUR than rubbers like SBR, PDMS and BR owing to its low degree of unsaturation. The investigation on the foams is the first of its kind to be reported.     

A new combined computational and NMR-spectroscopical strategy for the identification of additional conformational constraints of the bound ligand in an aprotic solvent

This study documents the feasibility of switching to an aprotic medium in sugar receptor research. The solvent change offers additional insights into mechanistic details of receptor--carbohydrate ligand interactions. If a receptor retained binding capacity in an aprotic medium, solvent-exchangeable protons of the ligand would not undergo transfer and could act as additional sensors, thus improving the level of reliability in conformational analysis. To probe this possibility, we first focused on hevein, the smallest lectin found in nature. The NMR-spectroscopic measurements verified complexation, albeit with progressively reduced affinity by more than 1.5 orders of magnitude, in mixtures of up to 50% dimethyl sulfoxide (DMSO). Since hevein lacks the compact beta-strand arrangement of other sugar receptors, such a structural motif may confer enhanced resistance to solvent exchange. Two settings of solid-phase activity assays proved this assumption for three types of alpha- and/or beta-galactoside-binding proteins, that is, a human immunoglobulin G (IgG) subfraction, the mistletoe lectin, and a member of the galectin family of animal lectins. Computer-assisted calculations and NMR experiments also revealed no conspicuous impact of the solvent on the conformational properties of the tested ligands. To define all possible nuclear Overhauser effect (NOE) contacts in a certain conformation and to predict involvement of exchangeable protons, we established a new screening protocol applicable during a given molecular dynamics (MD) trajectory and calculated population densities of distinct contacts. Experimentally, transferred NOE (tr-NOE) experiments with IgG molecules and the disaccharide Gal'alpha1-3Galbeta1-R in DMSO as solvent disclosed that such an additional crosspeak, that is, Gal'OH2--GalOH4, was even detectable for the bound ligand under conditions in which spin diffusion effects are suppressed. Further measurements with the plant lectin and galectins confirmed line broadening of ligand signals and gave access to characteristic crosspeaks in the aprotic solvent and its mixtures with water. Our combined biochemical, computational, and NMR-spectroscopical strategy is expected to contribute notably to the precise elucidation of the geometry of ligands bound to compactly folded sugar receptors and of the role of water molecules in protein--ligand (carbohydrate) recognition, with relevance to areas beyond the glycosciences.     

Comparing techniques for authorship attribution of source code

Attributing authorship of documents with unknown creators has been studied extensively for natural language text such as essays and literature, but less so for non‐natural languages such as computer source code. Previous attempts at attributing authorship of source code can be categorised by two attributes: the software features used for the classification, either strings of n tokens/bytes (n‐grams) or software metrics; and the classification technique that exploits those features, either information retrieval ranking or machine learning. The results of existing studies, however, are not directly comparable as all use different test beds and evaluation methodologies, making it difficult to assess which approach is superior. This paper summarises all previous techniques to source code authorship attribution, implements feature sets that are motivated by the literature, and applies information retrieval ranking methods or machine classifiers for each approach. Importantly, all approaches are tested on identical collections from varying programming languages and author types. Our conclusions are as follows: (i) ranking and machine classifier approaches are around 90% and 85% accurate, respectively, for a one‐in‐10 classification problem; (ii) the byte‐level n‐gram approach is best used with different parameters to those previously published; (iii) neural networks and support vector machines were found to be the most accurate machine classifiers of the eight evaluated; (iv) use of n‐gram features in combination with machine classifiers shows promise, but there are scalability problems that still must be overcome; and (v) approaches based on information retrieval techniques are currently more accurate than approaches based on machine learning. Copyright © 2012 John Wiley & Sons, Ltd.