CHEMICAL SCIENCES

Interactions between the leukocyte adhesion receptor L-selectin and P-selectin glycoprotein ligand-1 play an important role in regulating the inflammatory response by mediating leukocyte tethering and rolling on adherent leukocytes. In this study, we have examined the effect of post-translational modifications of PSGL-1 including Tyr sulfation and presentation of sialylated and fucosylated O-glycans for L-selectin binding. The functional importance of these modifications was determined by analyzing soluble L-selectin binding and leukocyte rolling on CHO cells expressing various glycoforms of PSGL-1 or mutant PSGL-1 targeted at Nterminal Thr or Tyr residues. Simultaneous expression of core-2 ␤1,6-N-acetylglucosaminyltransferase and fucosyltransferase VII was required for optimal L-selectin binding to PSGL-1. Substitution of Thr-57 by Ala but not of Thr-44, strongly decreased L-selectin binding and leukocyte rolling on PSGL-1. Substitution of Tyr by Phe revealed that PSGL-1 Tyr-51 plays a predominant role in mediating L-selectin binding and leukocyte rolling whereas Tyr-48 has a minor role, an observation that contrasts with the pattern seen for the interactions between PSGL-1 and P-selectin where Tyr-48 plays a key role. Molecular modeling analysis of L-selectin and Pselectin interactions with PSGL-1 further supported these observations. Additional experiments showed that core-2 O-glycans attached to Thr-57 were also of critical importance in regulating the velocity and stability of leukocyte rolling. These observations pinpoint the structural characteristics of PSGL-1 that are required for optimal interactions with L-selectin and may be responsible for the specific kinetic and mechanical bond properties of the L-selectin-PSGL-1 adhesion receptorcounterreceptor pair.

Transcription factor IIICZ (TFIIICZ), together with other transcription factors (TFIIIB and TFIIICl), is required for the in vitro transcription of tRNA and adenovirus VA genes by RNA polymerase 111. Previous studies have shown that TFIIICZ is a high molecular weight (-500,000) protein which binds with high affinity to the B-box promoter element of tRNA-type genes. A polypeptide of M , -250,000 is in close association with DNA in the specific complex between TFIIICZ and the B-box promoter element. Here we describe the purification of TFIIICZ by a factor of -25,000 from nuclear extracts of HeLa cells by ionic exchange, affinity, and hydrophobic chromatography and sedimentation velocity centrifugation. The most purified fractions contain polypeptides of approximately 230 kDa (corresponding to the polypeptide which can be cross-linked to VA1 DNA), 110,100,80, and 60 kDa which co-sediment with TFIIICZ B-box specific binding and in vitro transcriptional activities.

This paper presents a new manufacturing method to generate monodisperse microbubble contrast agents with polydispersity index (σ) values of <2% through microfluidic flow-focusing. Micronsized lipid shell-based perfluorocarbon (PFC) gas microbubbles for use as ultrasound contrast agents were produced using this method. The poly(dimethylsiloxane) (PDMS)-based devices feature expanding nozzle geometry with a 7 μm orifice width, and are robust enough for consistent production of microbubbles with runtimes lasting several hours. With high-speed imaging, we characterized relationships between channel geometry, liquid flow rate Q, and gas pressure P in controlling bubble sizes. By a simple optimization of the channel geometry and Q and P, bubbles with a mean diameter of <5 μm can be obtained, ideal for various ultrasonic imaging applications. This method demonstrates the potential of microfluidics as an efficient means for custom-designing ultrasound contrast agents with precise size distributions, different gas compositions and new shell materials for stabilization, and for future targeted imaging and therapeutic applications.

Capsaicin, the principal component of Capsicum fruits, strongly inhibited the in vitro mutagenic activity of five heterocyclic amines (HCAs) in Salmonella typhimurium strain TA98 by hamster liver microsomes. This correlated with the inhibition of microsome associated demethylation of methoxyresorufin (MROD) by capsaicin. MROD activity is mediated by cytochrome P450 1A2 and CYP450 1A2 mediates the metabolic activation of HCAs. Enzyme kinetics studies indicated a noncompetitive type of inhibition by capsaicin. Liver microsomes prepared from hamsters 6 h and 24 h after administration of a single oral dose of capsaicin in olive oil at either 2 mg/kg or 10 mg/kg body weight expressed a small but statistically significant inhibition of MROD activity compared with microsomes from control (untreated) animals. These results suggest that capsaicin can modulate the activity of cytochrome P450 1A2.

The intermetallic La 2 MgNi 9 has been investigated as negative electrode material for NiMH battery by means of in situ neutron powder diffraction. This hydrideforming compound exhibits suitable plateau pressures ranging within the practical electrochemical window and leads to significant reversible electrochemical capacities. Charge and discharge of the composite electrode have been performed in beam following various current rates and galvanostatic intermittent titration. From the diffraction data analysis, phase amounts and cell volumes have been extracted, allowing the interpretation of the hydride formation and decomposition. From the evolution of the diffraction line widths, differences are observed between charge and discharge with the possible formation of an intermediate γ phase on charge. The electrode readily responds to current rate variations and does not show any kinetic limitation in the range C/10 and C/5 (C/n: full capacity C in n hours). This material shows excellent properties regarding electrochemical storage of energy.

The goal of this study was to experimentally test the additivity of the electrostatic substituent effects (SEs) for the aromatic stacking interaction. The additivity of the SEs was assessed using a small molecule model system that could adopt an offset face-to-face aromatic stacking geometry. The intramolecular interactions of these molecular torsional balances were quantitatively measured via the changes in a folded/unfolded conformational equilibrium. Five different types of substituents were examined (CH 3 , OCH 3 , Cl, CN, and NO 2 ) that ranged from electron-donating to electron-withdrawing. The strength of the intramolecular stacking interactions was measured for 21 substituted aromatic stacking balances and 21 control balances in chloroform solution. The observed stability trends were consistent with additive SEs. Specifically, additive SE models could predict SEs with an accuracy from ±0.01 to ±0.02 kcal/mol. The additive SEs were consistent with Wheeler and Houk's direct SE model. However, the indirect or polarization SE model cannot be ruled out as it shows similar levels of additivity for two to three substituent systems, which were the number of substituents in our model system. SE additivity also has practical utility as the SEs can be accurately predicted. This should aid in the rational design and optimization of systems that utilize aromatic stacking interactions.

A state-of-the-art overview of N-dopant characterizations in nano-TiO 2 second-generation photocatalysts is provided. The related literature is very rich and sometimes offers contrasting interpretations. Here we critically discuss up-to-date literature results and our own findings, as retrieved by several experimental (BET, HR-TEM, XPS, DRS, HR-XRPD, EXAFS, electrochemical tools) and theoretical (periodic DFT) techniques. Our intent is to pull together outcomes from very different and complementary sources to make an as much as possible coherent picture of the morphological, electrochemical and electronic properties of N-TiO 2 materials. It is commonly accepted that critical issues to be considered in the design of high-performing N-TiO 2 photocatalysts are synthetic strategy, defect concentration and chemical nature of the lattice point defects. We focus on the latter two issues, with emphasis on sol-gel prepared materials, according to the specific area of expertise of our group. The problem of the chemical nature of guest N species into the lattice is crucial, as substitutional (N s ) or interstitial (N i ) nitrogen place their valence states just above the valence band or deeper into the band gap. Overall, we show how synergism among experimental and theoretical techniques is decisive to disentangle structural, electronic and morphological effects in complex N-doped TiO 2 matrices.

Nosso interesse quimiotaxonômico sobre Neoraputia nos estimulou a examinar N. paraensis, visando a busca de alcalóides. As frações foram monitoradas via RMN 1 H e ESI-EM/EM e foram analisadas somente aquelas cujos espectros apresentavam características de alcalóides do ácido antranílico e flavonóides não isolados anteriormente. Foram isolados do caule os alcalóides flindersina,

Solid-state foaming of cyclic olefin copolymer (COC, Topas 6017) using carbon dioxide (CO 2 ) was investigated. Before the foaming experiment, the solubility of CO 2 in the polymer at various saturation pressure (5−10 MPa) and saturation temperature (40°C) was measured using the ex-situ gravimetric method. The effects of the saturation pressure, foaming temperature, and foaming time on the foam structure were systematically investigated. Ultramicrocelluar foams with a cell size of 0.5 μm and cell density over 10 12 cells/cm 3 were successfully prepared. Moreover, it was observed that the system, which was strongly plasticized by CO 2 , would transition from foaming to crazing under certain conditions. The phenomenon was examined in detail and understood by a proposed mechanism that accounts for both homogeneous nucleation and stress fields induced crazing.

Waste management has become an issue of increasing concern worldwide. These products are filling landfills and reducing the amount of livable space. Leachate produced from landfills contaminates the surrounding environment. The conventional incineration process releases toxic airborne fumes into the atmosphere. Researchers are working continuously to explore sustainable ways to manage and recycle waste materials. Recycling and reuse are the most efficient methods in waste management. The pavement industry is one promising sector, as different sorts of waste are being recycled into asphalt concrete and bitumen. This paper provides an overview of some promising waste products like high-density polyethylene, marble quarry waste, building demolition waste, ground tire rubber, cooking oil, palm oil fuel ash, coconut, sisal, cellulose and polyester fiber, starch, plastic bottles, waste glass, waste brick, waste ceramic, waste fly ash, and cigarette butts, and their use in asphalt concrete...

We report on structural, magnetic, electrical, and thermodynamic properties of Gd-doped LaMnO3 single crystals for Gd doping levels 0 <= x <= 1. At room temperature, for all doping levels the orthorhombic O' phase is indicative for a strong Jahn-Teller distortion. All compositions are insulating. The magnetism of La$_{1-x}$Gd$_x$MnO$_3$ is dominated by the relatively strong Mn-Mn exchange. The weakening of the antiferromagnetic interactions due to the significant decrease f the Mn-O-Mn bond angles leads to the continuous suppression of the magnetic phase-transition temperatures into the antiferromagnetic low-temperature phase for increasing Gd doping. The magnetization can only be explained assuming canting of the manganese spins. The magnetic moments of Gd are weakly antiferromagnetically coupled within the sublattice and are antiferromagnetically coupled to the Mn moments. For intermediate concentrations compensation points are found, below which the spontaneous magnetization becomes negative. In pure GdMnO3 the Mn spins undergo a transition into a complex, probably incommensurate magnetic structure at 41.5 K, followed by a further ordering transition at 16-20 K revealing weak ferromagnetism due to canting and finally by the onset of magnetic order in the Gd sublattice at 6.5 K. At the lowest temperatures and low external fields both magnetic sublattices reveal a canted structure with antiparallel ferromagnetic components.

N-F-co-embedded titania (N-F-TiO2) photocatalysts with varying N:F ratios were synthesized and tested for their ability to photocatalyze the degradation of pollutants present at indoor air levels using visible light. The synthesis was achieved using a solvothermal process with tetrabutyl titanate, urea and ammonium fluoride as sources of Ti, N and F, respectively. Three selected volatile organic compounds (toluene, ethyl benzene and o-xylene) were selected as the test pollutants. The prepared composites were characterized using X-ray diffraction, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and Ultra-violet (UV)-visible spectroscopy. The photocatalytic degradation efficiencies of N-F-TiO2 composites were higher than those obtained using pure TiO2 and N-TiO2. Moreover, these efficiencies increased as the N:F ratio decreased from sixteen to eight, then decreased as it dropped further to three, indicating the presence of an optimal N:F ratio. Meanwhile, as retention time decreased from 12.4 to 0.62 s, the average photocatalytic efficiencies decreased from 65.4% to 21.7%, 91.5% to 37.8% and 95.8% to 44.7% for toluene, ethyl benzene and o-xylene, respectively. In contrast, the photocatalytic reaction rates increased as retention time decreased. In consideration of all of these factors, under optimized operational conditions, the prepared N-F-TiO2 composites could be utilized for the degradation of target pollutants at indoor air levels using visible light. OPEN ACCESS Materials 2015, 8 32

We show that the shape of electroluminescence transients in organic semiconductors can be conveniently used to obtain the diffusion constant D of injected charge carriers, enabling the study of generalized Einstein relationship under nonequilibrium conditions as a function of the electric field. The appearance of peak at the onset of transient is shown to be the signature of diffusive regime of transport. We demonstrate it for two representative materials, Alq 3 and polymer poly [2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene vinylene], with the focus on the role of hot carriers in transport and their diffusivity.

The usefulness of the turbulent k-model for simulation of flow in a stirred vessel was studied in detail. For optimization, the effects of model parameters on flow characteristics were analyzed. It was observed that, any single set of model parameters could not yield even reasonable agreement between the model predictions and the experimental observations throughout the vessel. Therefore, the concept of zonal modeling was introduced for the r-z plane. It was observed that with the introduction of zonal modeling, the predicted values of flow variables, except the energy dissipation rate, were in good agreement with experimental data even close to the top surface of the tank. The same results could not be obtained with the standard set of parameters and a single zone. Local turbulent energy dissipation rate ( ) was calculated using the expression ( ) k 3/2 /L res ) proposed by . The zonal modeling prediction was better than the prediction by a standard set of parameters. However, above the impeller, a wide discrepancy between the predicted and experimental value for energy dissipation rate was observed.

An extensive programme of experiments was conducted in the former USSR on transfer of radionuclides to a wide range of different agricultural animals. Only a few of these studies were made available in the English language literature or taken into account in international reviews of gastrointestinal uptake. The paper gives extended information on Russian research on radionuclide absorption in the gut of farm animals performed in controlled field and laboratory experiments from the 1960s to the current time. The data presented in the paper, together with English language values, will be used to provide recommended values of absorption specifically for farm animals within the revision of the IAEA Handbook of Parameter Values IAEA [International Atomic Energy Agency, 1994. Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Temperate Environments, IAEA technical reports series No. 364. International Atomic Energy Agency, Vienna].

Bifunctional, Lewis, and Brønsted acidic molecular sieves were prepared by stepwise zinc ion exchange of zeolite BEA. The relation between the location of the Zn 2+ cations in the zeolite structure and the Lewis acidity of the metal cations was explored. Several techniques were used for the detailed characterization of the material, including IR spectroscopy, with pyridine and acetonitrile as probe molecules, temperature programmed desorption, with ammonia and 2-propylamine as probe molecules, X-ray absorption spectroscopy, and 27 Al MAS and MQMAS NMR spectroscopy. At low zinc concentrations (<0.15 Zn/Al) the cations are preferentially incorporated in the vicinity of two framework aluminum atoms. With increasing zinc loading (0.15 e Zn/Al e 0.26), additional cation sites are created at nearby framework aluminum pairs with two zinc cations being bridged by an oxygen atom. At higher zinc loading (0.26 < Zn/Al < 0.77) zinc oxide is formed in addition to the other two Zn 2+ species.

For an inconclusive study of unimolecular cleavage of cyclopropanes, see: A. 6. Chmurny and D. J. Cram, J. Am. Chem. SOC., 95,4237 (1973), and previous papers in this series. (27) The first examples of reliance on configurationally defined cyclopropanes with intramolecular displacement as a strategy in stereospecific synthesis were provided by G. Stork and associates, see: G. Stork and M. Marx, J. Am. Chem. Soc., 91, 237 1 (1969); G. Stork and M. Gregson, ibid., 91,2373Gregson, ibid., 91, (1969. It is interesting to note that those ring openings which involved acid catalysis occurred strictly in the fused mode. (28) J. Dynak. Ph.D. Thesis, University of Pittsburgh, 1975. (29) D. Landine and R. Rolla, Synthesis, 389 (1976). (30) (a) S. Tripett and D. M. Walker, J. Chem. Soc., 1266 (1961); (b) M. Regitz, Chem. Ber., 99, 3128 (1966); (c) these conditions were provided to us by Professor 6. M. Trost. (31) E. N. Marvel1 and T. Li, Synthesis, 457 (1973). (32) The 250-MHz spectra of lactam alcohols 25 and 26 and of trachelanthamidine and isoretronecanol are provided in the microfilm edition (consult masthead page for ordering information). (33) Combustion analyses were performed by Galbraith Laboratories, Knoxville Tenn. Infrared spectra were measured on a Perkin-Elmer 137 lnfracord spectrophotometer. NMR spectra were obtained at 60 MHz on Varian A-60D cf T-60 systems and at 250 MHz as indicated, with tetramethylsilane as an internal standard. Data are reported in 6 (ppm) from the Me&i signal. Melting points are uncorrected.

We have used coarse-grained simulation methods to investigate the effect of stretching-induced structure orientation on the proton conductivity of Nafion-like polymer electrolyte membranes. Our simulations show that uniaxial stretching causes the hydrophilic regions to become elongated in the stretching direction. This change has a strong effect on the proton conductivity, which is enhanced along the stretching direction, while the conductivity perpendicular to the stretched polymer backbone is reduced. In a humidified membrane, stretching also causes the perfluorinated side chains to tend to orient perpendicular to the stretching axis. This in turn affects the distribution of water at low water contents. The water forms a continuous network with narrow bridges between small water clusters absorbed in head group multiplets. In a dry membrane the side chains orient along the stretching direction.

Metal-organic frameworks (MOFs) for hydrogen storage have continued to receive intense interest over the past decade. MOFs are a class of organic-inorganic hybrid crystalline materials consisting of metallic moieties that are linked by strong coordination bonds to organic ligands. They exhibit a great structural diversity and possess low weight, exceptionally high surface areas, large free volumes, and tunable pore sizes and functionalities, making them extremely attractive for a variety of applications such as hydrogen storage. For these reasons MOFs have been extensively studied. In this paper, a review of recent developments on hydrogen storage in MOFs is presented, with a focus on the effects of various factors including open metal sites, 'guest' metal ions, ligand functionalization, surface area, pore volume, pore size, and Pt or Pd metal nanoparticles, on hydrogen storage. In addition, the review examines the emerging research on MOF hybrid hydrogen storage systems, primarily in the context of employing MOFs for nanoconfinement of high temperature hydrogen storage materials. The review focuses on experimental studies.

Calcium looping is an emerging CO 2 capture technology based on cyclic calcination/carbonation reactions using calcium-based sorbents. Steam is typically present in flue/fuel gas streams from combustion or gasification and in the calciner used for sorbent regeneration. The effect of steam in the calciner on sorbent performance has received little attention in the literature. Here, experiments were conducted using a thermogravimetric analyzer (TGA) to determine the effect of steam injection during calcination on sorbent reactivity during carbonation. Two Canadian limestones, Cadomin and Havelock, were tested, and various levels of steam (up to 40%) were injected in the sorbent regeneration process for 15 calcination/carbonation cycles. All concentrations of steam examined were found to increase sorbent reactivity for carbonation for both sorbents. In these experiments, 15% steam concentration with calcination had the largest impact on carrying capacity for both sorbents. Steam changes the morphology of the sorbent while calcination is occurring, probably causing a shift from smaller to larger pores, resulting in a structure which increases carrying capacity. It was also demonstrated that steam addition produced a larger impact on sorbent reactivity for carbonation than for calcination.

Rotational immobilization of proteins permits characterization of the internal peptide and water molecule dynamics by magnetic relaxation dispersion spectroscopy. Using different experimental approaches, we have extended measurements of the magnetic field dependence of the proton-spin-lattice-relaxation rate by one decade from 0.01 to 300 MHz for 1 H and showed that the underlying dynamics driving the protein 1 H spin-lattice relaxation is preserved over 4.5 decades in frequency. This extension is critical to understanding the role of 1 H 2 O in the total proton-spin-relaxation process. The fact that the proteinproton-relaxation-dispersion profile is a power law in frequency with constant coefficient and exponent over nearly 5 decades indicates that the characteristics of the native protein structural fluctuations that cause proton nuclear spin-lattice relaxation are remarkably constant over this wide frequency and length-scale interval. Comparison of protein-proton-spin-lattice-relaxation rate constants in protein gels equilibrated with 2 H 2 O rather than 1 H 2 O shows that water protons make an important contribution to the total spin-lattice relaxation in the middle of this frequency range for hydrated proteins because of water molecule dynamics in the time range of tens of ns. This water contribution is with the motion of relatively rare, long-lived, and perhaps buried water molecules constrained by the confinement. The presence of water molecule reorientational dynamics in the tens of ns range that are sufficient to affect the spin-lattice relaxation driven by 1 H dipole-dipole fluctuations should make the local dielectric properties in the protein frequency dependent in a regime relevant to catalytically important kinetic barriers to conformational rearrangements.

Eco-park LCA metrics Environmental optimization Criteria air contaminants a b s t r a c t Environmental considerations are receiving an increased amount of attention in both the residential and industrial sectors. In order to achieve a reduction in emissions of harmful substances to the air, water and land to meet national targets, industrial chemical producers must explore new avenues to reduce the impact that they have on the environment.

Two thermodynamically based, theoretical models are developed to predict the selectivity coefficients for Ca 2 + / Cu 2 + and Pb 2 + /Cu 2 + in ion flotation with sodium dodecylsulfate (SDS) as the collector. Pseudo selectivity coefficients predicted from surface tension measurements are 1.12 and 1.69 for Ca 2 + /Cu 2 + and Pb 2 + /Cu 2 + . This agrees rather poorly with experimentally measured selectivity coefficients of 1.44 and 2.14, but does predict the order of selectivity Cu 2 + BCa 2 + BPb 2 + . The selectivity coefficients estimated by the dehydration model are 1.55 and 2.07 for Ca 2 + /Cu 2 + and Pb 2 + /Cu 2 + , respectively, which agrees well with the experimentally measured values.

Most industrially applied polymer resins and composites have low surface free energy and lack polar functional groups on their surface, resulting in inherently poor adhesion properties. A strong research momentum to understand polymer adhesion in the last decade has been motivated by the growing needs of the automotive and aerospace industries for better adhesion of components and surface coatings. This paper reviews the recent research efforts on polymer adhesion with a special focus on adhesion mechanisms. It starts with an introduction to adhesion with explanatory notes on adhesion phenomena. Recent research on the adhesion mechanisms of mechanical coupling, chemical bonding and thermodynamic adhesion is then discussed. The area of adhesion promoters is reviewed with the focus on plasma and chemical treatments, along with direct methods for adhesion measurement. The topics of polymer blends and reactive polymerization are considered and the interactions with adhesion mechanisms are reported. The concluding section provides recommendations regarding future research on the contentious aspects of currently accepted adhesion mechanisms and on strategies for enhancing polymer adhesion strength.

Outdoor mesocosms (experimental drainage ditches) were treated repeatedly with linuron at nominal concentrations of 0, 0.5, 5, 15, and 50 g/L. After each of three treatments (with 4-week intervals), the systems were kept static for 1 week. Subsequently, they were flushed with nonpolluted surface water with a residence time of 5 d until the next treatment. Species composition and abundance of macrophytes, periphyton, phytoplankton, zooplankton, and macroinvertebrates were examined at prefixed time intervals. During the treatment periods, significant decreases in oxygen concentration and pH were observed, whereas the systems recovered during the flushing periods. The effects of the pulsed treatments on the structural endpoints (biota) were rarely significant and consistently were difficult to interpret. We conclude that under these experimental conditions, pulsed treatment with linuron causes only minor and negligible effects on the abundance of organisms in mesocosms, even when maximum permissible concentrations are exceeded by about 80 times. Risk assessment based on the more sensitive physiologic and functional endpoints suggested that the safety factor of 0.1 times the acute EC50 of the most sensitive standard alga (Scenedesmus acutus), as adopted in the Uniform Principles of the European Union, is sufficient to protect the community of the mesocosms in an exposure regime that was realistic for Dutch drainage ditches, using a photosynthesis inhibitor as the benchmark compound.

Ethyl glucuronide (EtG) is a minor and direct metabolite of ethanol. EtG is incorporated into the growing hair allowing retrospective investigation of chronic alcohol abuse. In this study, we report the development and the validation of a method using gas chromatography–negative chemical ionization tandem mass spectrometry (GC–NCI-MS/MS) for the quantification of EtG in hair. EtG was extracted from about 30mg

April 2016 sees the 30 th anniversary of the accident at the Chernobyl nuclear power plant. As a consequence of the accident populations were relocated in Belarus, Russia and Ukraine and remedial measures were put in place to reduce the entry of contaminants (primarily 134þ137 Cs) into the human food chain in a number of countries throughout Europe. Remedial measures are still today in place in a number of countries, and areas of the former Soviet Union remain abandoned. The Chernobyl accident led to a large resurgence in radioecological studies both to aid remediation and to be able to make future predictions on the post-accident situation, but, also in recognition that more knowledge was required to cope with future accidents. In this paper we discuss, what in the authors' opinions, were the advances made in radioecology as a consequence of the Chernobyl accident. The areas we identified as being significantly advanced following Chernobyl were: the importance of semi-natural ecosystems in human dose formation; the characterisation and environmental behaviour of 'hot particles'; the development and application of countermeasures; the "fixation" and long term bioavailability of radiocaesium and; the effects of radiation on plants and animals.

Coupling of localized surface plasmon resonances results in singular effects at the void space between noble metal nanoparticles. However, implementation of practical applications based on plasmon coupling calls for the high yield production of metal nanoparticle clusters (dimers, trimers, tetramers,.) with small gaps. Therefore, controlled assembly using colloid chemistry methods is an emerging and promising field. We present a brief overview over the controlled assembly of plasmonic nanoparticle clusters by colloid chemistry methods, together with a description of their plasmonic properties and some applications, with an emphasis in sensing through surface-enhanced Raman scattering spectroscopy for bio-detection purposes. We point out the important role of separation methods to obtain colloidal clusters in high yield. A special encouragement to explore assembly of anisotropic building blocks is pursued.

During the resorbable-polymer-boom of the 1970s and 1980s, polycaprolactone (PCL) was used in the biomaterials field and a number of drug-delivery devices. Its popularity was soon superseded by faster resorbable polymers which had fewer perceived disadvantages associated with long term degradation (up to 3-4 years) and intracellular resorption pathways; consequently, PCL was almost forgotten for most of two decades.

Studies were conducted to investigate membrane fouling in Ultrafiltration (UF) of emulsions and suspensions. A laboratory scale plate and frame cross flow membrane filtration setup was fabricated and installed. Oil and gelatin were used to make the emulsion and suspension as feed. The feed was pumped to the UF cell at a cross flow velocity of 1 m/s and a temperature of 30 C. It was found that development of membrane fouling is a dynamic process of two distinctive stages. Pore blocking is dominant resistance at initial period of UF and cake resistance begins to dominate following the initial pore blocking. The results show that cake layer resistance increases with increasing feed concentration and transmembrane pressure. UF of oily emulsions and dilute gelatin suspensions, which produce highly compressible cake (gel) layers, were studied under constant pressure and constant feed concentration, respectively. In this research, a new model which is a modified cake layer filtration model was developed. Model predictions show an excellent agreement with experimental data.