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This paper presents a multilayered ecosystem modelling approach that combines the simulation of the biogeochemistry of a coastal ecosystem with the simulation of the main forcing functions, such as catchment loading and aquaculture activities. This approach was developed as a tool for sustainable management of coastal ecosystems. A key feature is to simulate management scenarios that account for changes in multiple uses and enable assessment of cumulative impacts of coastal activities. The model was applied to a coastal zone in China with large aquaculture production and multiple catchment uses, and where management efforts to improve water quality are under way. Development scenarios designed in conjunction with local managers and aquaculture producers include the reduction of fish cages and treatment of wastewater. Despite the reduction in nutrient loading simulated in three different scenarios, inorganic nutrient concentrations in the bay were predicted to exceed the thresholds for poor quality defined by Chinese seawater quality legislation. For all scenarios there is still a Moderate High to High nutrient loading from the catchment, so further reductions might be enacted, together with additional decreases in fish cage culture. The model predicts that overall, shellfish production decreases by 10%–28% using any of these development scenarios, principally because shellfish growth is being sustained by the substances to be reduced for improvement of water quality. The model outcomes indicate that this may be counteracted by zoning of shellfish aquaculture at the ecosystem level in order to optimize trade-offs between productivity and environmental effects. The present case study exemplifies the value of multilayered ecosystem modelling as a tool for Integrated Coastal Zone Management and for the adoption of ecosystem approaches for marine resource management. This modelling approach can be applied worldwide, and may be particularly useful for the application of coastal management regulation, for instance in the implementation of the European Marine Strategy Framework Directive. published

The complexes formed by combining Pd(OAc)2 and iminophosphine ligands (P^N) are active catalysts in Suzuki–Miyaura cross-coupling reactions under mild conditions. Aryl bromides and iodides, as well as benzyl chlorides give the corresponding coupled products in high yields at low temperatures (25–50 °C) using these catalysts. Iminophosphines containing the most sterically demanding groups attached to the N-imino moiety were the most effective ligands. New divalent Pd complexes of known iminophosphines were synthesised and their activity was compared with the in situ generated catalyst system. The complex resulting from the oxidative addition of 4-bromo anisole [Pd(4-CH3OC6H4)Br(P^N)] was more active than the in situ generated system. However, palladacycles containing the iminophosphine ligand (e.g., {[C6H4CH(Me)2St-Bu]Pd(P^N)}+PF6−) were less active than the in situ generated catalyst due to the greater stability of the complexes that involve two bidentate ligands. Poisoning tests demonstrated that homogeneous mononuclear palladium species containing the iminophsophine ligand were responsible for the catalytic activity.

article i nfo Sustainable aquaculture Ecosystem approach to aquaculture (EAA) Ecological-economic modelling Integrated coastal management (ICM) MARKET model This paper presents a Modeling Approach to Resource economics decision-maKing in EcoaquaculTure (MARKET model). The MARKET model was developed as a scenario-testing tool to provide insights on the ecological and economic interactions, which is a critical issue for sustainable aquaculture management. As a case study, the model was applied to simulate shellfish production in an embayment located in the East China Sea. A set of scenarios was used to compare the model outputs with expected trends and to test its capability to simulate relevant management scenarios. The comparison of simulated scenarios indicates that the MARKET model outputs followed the expected trends regarding both standard economic theory for consumption and production, and ecological economic theory. In all the scenarios we tested the area available for aquaculture was found to impose a limitation on production before it became less profitable to expand production. As such, in this case study, the production in the long run does not meet increasing demand. Reduction of the maximum cultivation area was simulated in one of the scenarios as an example of a conservation measure. As expected there was a reduction of the net profit of the farmers compared with the standard simulation. On the other hand, this scenario combined with an increase in price growth rate simulates a compensatory measure that led to a net profit in the same range as observed in the standard simulation. Overall the MARKET model provides insights and raises questions useful for the implementation of an ecosystem approach to aquaculture. Further developments include the simulation of waste generated by cultivated species in order to better support sustainable management objectives.

Proteins incorporated into phospholipid Langmuir-Blodgett (LB) films are a good model system for biomembranes and enzyme immobilization studies. The specific fluidity of biomembranes, an important requisite for enzymatic activity, is naturally controlled by varying phospholipid compositions. In a model system, instead, LB film fluidity may be varied by covering the top layer with different substances able to interact simultaneously with the phospholipid and the protein to be immobilized. In this study, we immobilized a carbohydrate rich Neurospora crassa alkaline phosphatase (NCAP) in monolayers of the sodium salt of dihexadecylphosphoric acid (DHP), a synthetic phospholipid that provides very condensed Langmuir films. The binding of NCAP to DHP Langmuir-Blodgett (LB) films was mediated by the anionic polysaccharide iota-carrageenan (iota-car). Combining results from surface isotherms and the quartz crystal microbalance technique, we concluded that the polysaccharide was essential to promote the interaction between DHP and NCAP and also to increase the fluidity of the film. An estimate of DHP:iota-car ratio within the film also revealed that the polysaccharide binds to DHP LB film in an extended conformation. Furthermore, the investigation of the polysaccharide conformation at molecular level, using sum-frequency vibrational spectroscopy (SFG), indicated a preferential conformation of the carrageenan molecules with the sulfate groups oriented toward the phospholipid monolayer, and both the hydroxyl and ether groups interacting preferentially with the protein. These results demonstrate how interfacial electric fields can reorient and induce conformational changes in macromolecules, which may significantly affect intermolecular interactions at interfaces. This detailed knowledge of the interaction mechanism between the enzyme and the LB film is relevant to design strategies for enzyme immobilization when orientation and fluidity properties of the film provided by the matrix are important to improve enzymatic activity.

The reconstitution of membrane proteins into liposomes is a useful tool to prepare antigenic components that induce immunity. We have investigated the influence of the dipalmitoylphosphatidylcholine (DPPC)/cholesterol molar ratio on the incorporation of a GPI-protein from Leishmania amazonensis on liposomes and Langmuir monolayers. The latter system is a well behaved and practical model, for understanding the effect of variables such as surface composition and lipid packing on protein incorporation. We have found that the DPPC/cholesterol molar ratio significantly alters the incorporation of the GPI-protein. In the absence of cholesterol, reconstitution is more difficult and proteoliposomes cannot be prepared, which we correlated with disruption of the DPPC layer. Our results provide important information that could be employed in the development of a vaccine system for this disease or be used to produce other GPI-systems for biotechnological application.

There are practical and academic situations that justify the study of calcium carbonate crystallization and especially of systems that are associated with organic matrices and a confined medium. Despite the fact that many different matrices have been studied, the use of well-behaved, thin organic films may provide new knowledge about this system. In this work, we have studied the growth of calcium carbonate particles on well-defined organic matrices that were formed by layer-by-layer (LbL) polyelectrolyte films deposited on phospholipid Langmuir-Blodgett films (LB). We were able to change the surface electrical charge density of the LB films by changing the proportions of a negatively charged lipid, the sodium salt of dimyristoyl-sn-glycero-phosphatidyl acid (DMPA), and a zwitterionic lipid, dimyristoyl-sn-glycero-phosphatidylethanolamine (DMPE). This affects the subsequent polyelectrolyte LbL film deposition, which also changes the the nature of the bonding (electrostatic interaction or hydrogen bonding). This approach allowed for the formation of calcium carbonate particles of different final shapes, roughnesses, and sizes. The masses of deposited lipids, polyelectrolytes, and calcium cabonate were quantified by the quartz crystal microbalance technique. The structures of obtained particles were analyzed by scanning electron microscopy.

Air-stable cyclopalladated compounds derived from the ortho-metalation of benzylic tert -butyl thioethers efficiently promote C–C coupling reactions and were studied mechanistically in the Suzuki reaction. The catalytic reaction was monitored by 19 F NMR and GC–MS and the decomposition of the S-palladacycle was studied under stoichiometric conditions, showing that these palladacycles serve as a reservoir of zerovalent palladium species. The formation of these species is initiated by attack of the arylboronic acid on the palladacycle resulting in the formation of an arylated palladacycle. Thereafter, this species undergoes a reductive elimination to form the active Pd(0) species. As a minor pathway, the Pd(0) species could also be generated in a pathway involving a reduction process that leads to the decomposition of the palladacycle to Pd(0) affording the ortho hydrogenated thioether. Poisoning studies and TEM analysis indicated the presence of palladium nanoparticles. Competitive experiments showed that electron-withdrawing substituents on the aryl halide and electron-donating substituents on the arylboronic acid facilitated the reaction. They also provide evidence that the soluble species formed from the oxidative addition, that are active for Heck and Suzuki reactions, are the same species.

The immobilization of enzymes in organized two-dimensional matrices is a key requirement for many biotechnological applications. In this paper, we used the Langmuir-Blodgett (LB) technique to obtain controlled architectures of urease immobilized in solid supports, whose physicochemical properties were investigated in detail. Urease molecules were adsorbed at the air-water interface and incorporated into Langmuir monolayers of the phospholipid dipalmitoyl phosphatidyl glycerol (DPPG). Incorporation of urease made DPPG monolayers more flexible and caused the reduction of the equilibrium and dynamic elasticity of the film. Urease and DPPG-urease mixed monolayers could be transferred onto solid substrates, forming LB films. A close packing arrangement of urease was obtained, especially in the mixed LB films, which was inferred with nanogravimetry and electrochemistry measurements. From the blocking effect of the LB films deposited onto indium tin oxide (ITO) substrates, the electrochemical properties of the LB films pointed to a charge transport controlled by the lipid architecture.

Many chitosan biological activities depend on the interaction with biomembranes, but so far it has not been possible to obtain molecular-level evidence of chitosan action. In this article, we employ Langmuir phospholipid monolayers as cell membrane models and show that chitosan is able to remove beta-lactoglobulin (BLG) from negatively charged dimyristoyl phosphatidic acid (DMPA) and dipalmitoyl phosphatidyl glycerol (DPPG). This was shown with surface pressure isotherms and elasticity and PM-IRRAS measurements in the Langmuir monolayers, in addition to quartz crystal microbalance and fluorescence spectroscopy measurements for Langmuir-Blodgett (LB) films transferred onto solid substrates. Some specificity was noted in the removal action because chitosan was unable to remove BLG incorporated into neutral dipalmitoyl phosphatidyl choline (DPPC) and cholesterol monolayers and had no effect on horseradish peroxidase and urease interacting with DMPA. An obvious biological implication of these findings is to offer reasons that chitosan can remove BLG from lipophilic environments, as reported in the recent literature.

This paper presents an ecosystem modelling approach aimed at improving shellfish aquaculture management by explicitly considering natural benthic biodiversity. This methodology uses a combination of benthic field survey data, sediment and bathymetric mapping, physiological models and dynamic ecosystem modelling. The Wild species Integration for Shellfish Ecoaquaculture (WISE) approach helps to understand the baseline food requirements for maintaining natural benthic biodiversity of suspension-feeding organisms, thus informing managers on potential upper thresholds for shellfish aquaculture. WISE was tested in four coastal systems in Europe and China, including bays, estuaries and sea loughs with widely differing aquaculture activities. In the European systems, where the aquaculture industry is developing, species diversity and abundance are much higher and suspension-feeding wild species play an important role in the consumption of food resources. Densities of wild individuals were estimated to be 13 ind m− 2 in Sanggou Bay (total: 2 × 109), 33 ind m− 2 in Xiangshan Gang (total: 122 × 109), 95 ind m− 2 in Carlingford Lough (total: 4.62 × 109) and 175 ind m− 2 in Loch Creran (total: 2.62 × 109). Total clearance rates by wild populations were calculated as 5% of the total volume d− 1 in Sanggou Bay (75 × 106 m3 d− 1), 11% d− 1 in Xiangshan Gang (434 × 106 m3 d− 1), 40% d− 1 in Loch Creran (93 – 99 × 106 m3 d− 1) and 45% d− 1 in Carlingford Lough (170–250 × 106 m3 d− 1). In relative terms, wild populations play a more important role than cultivated shellfish in clearing suspended particles from the European systems due to the much lower aquaculture activity. 56% and 76% of total primary production in Loch Creran and Carlingford Lough, respectively, are consumed annually by wild organisms, while less than 50% is consumed in Chinese systems (45% in Sanggou Bay and 2.9% in Xiangshan Gang). Integration of the WISE approach within broader ecological modelling illustrates some of the trade-offs between commercial aquaculture and the conservation of biodiversity, showing that rates of and capacities for shellfish culture are reduced when both wild and cultured suspension-feeding species are considered in relation to the available seston. When food resources are partitioned between wild and cultivated species, there is a decrease in individual length and weight (9 to 22% reduction in shell length and 24 to 52% reduction in total fresh weight for the Pacific oyster; reductions of 6% in length and 20% in weight for blue mussel; reductions of 4% in length and 13% in individual weight for bivalves in Xiangshan Gang), resulting in a lower aquaculture production (e.g. for Pacific oyster, a reduction of 12.5% in Carlingford Lough, 34% in Loch Creran and of 9% for bivalves in Xiangshan Gang).

The kinetics of adsorption to air-water interfaces of the biomembrane active transcription factors c-Fos, c-Jun and their mixtures is investigated. The adsorption process shows three distinct stages: a lag time, a fast pseudo zero-order stage, and a halting stage. The initial stage determines the course of the process, which is concentration dependent until the end of the fast stage. We show that c-Fos has faster adsorption kinetics than c-Jun over all three stages and that the interaction between both proteins is apparent in the adsorption profiles of the mixtures. Protein molecular reorganization at the interface determines the transition to the final adsorption stage of the pure proteins as well as that of the mixtures.

Managing combined sewage systems in large cities discharging to coastal waters, often bearing recreational activities, remains a challenge. Studying the impacts of such discharges requires the development of specific models. Hydrodynamic and water quality modelling of coastal waters employs numerical methods and algorithms, leading to the design of complex models which require expert use. The use of such models as decision support tools to simulate discharge impacts and define adequate corrective measures could represent a key part in meeting this challenge. In this paper, the authors describe the work undertaken to develop an operational decision support system (ODSS) methodology aiming to enable wastewater utilities' non-expert staff to carry out user-friendly scenario analysis based on computational fluid dynamics simulations. This article depicts the application and validation of the ODSS to the combined sewage system and the Tagus estuary of the city of Lisbon in Portugal. The ODSS was used for simulating the effects in the receiving coastal waters of a discharge caused by a scheduled maintenance operation in the sewage infrastructure. Results show that the use of such ODSS by non-expert staff increases their decision capabilities and knowledge of the wastewater utility's contribution to reducing negative impacts of sewage discharges on the receiving water bodies.

In this work, the operation of a standalone streetlamp PV system is modeled considering actual outdoor operation conditions. The model integrates all components required in a stand-alone PV system: PV panel, battery, charge controller and load. Electrical characteristics of each component are based on those of a streetlamp PV system, currently tested in Singapore. Using measured irradiance data, the model is able to predict the real-time current flow, battery operating voltage and state of charge. The simulations of the streetlamp system are done using real-measured irradiance data from Singapore and Boston. We find that for a long-term, uninterrupted operation of a standalone PV system actual meteorological conditions need to be considered. The real-time simulation method presented in this work allows better defining the size of the required solar panel and the battery capacity.

An individual growth model for penaeid shrimp is presented. The main physiological processes simulated were: ingestion, assimilation, faeces production, respiration and female reproduction. The model was used to quantify the most important physiological processes involved in growth and also to examine the effect of food availability and water temperature on shrimp final weight. The simulation reproduces the typical pattern of growth of penaeid shrimp, characterised by a rapid weight gain during the early life stages and by the achievement of asymptotic length in adults. The ingestion and respiration rates increased as the animal grew but the weight-specific rates decreased with an increase of shrimp weight. A sensitivity analysis showed that the model does not produce differences at a 10% change in juvenile food availability. On the other hand, a change of water temperature of the same magnitude had an effect on shrimp final weight. The model was developed in the visual simulation software Powersim™. The individual growth model presented in this paper may be integrated into population dynamics models in order to simulate the biomass and density throughout the stages of the shrimp life cycle; such models may be usefully applied both to penaeid aquaculture and to management of wild fisheries.

This paper reports the surface activity of phytase at the air-water interface, its interaction with lipid monolayers, and the construction of a new phytic acid biosensor on the basis of the Langmuir-Blodgett (LB) technique. Phytase was inserted in the subphase solution of dipalmitoylphosphatidylglycerol (DPPG) Langmuir monolayers, and its incorporation to the air-water interface was monitored with surface pressure measurements. Phytase was able to incorporate into DPPG monolayers even at high surface pressures, ca. 30 mN/m, under controlled ionic strength, pH, and temperature. Mixed Langmuir monolayers of phytase and DPPG were characterized by surface pressure-area and surface potential-area isotherms, and the presence of the enzyme provided an expansion in the monolayers (when compared to the pure lipid at the interface). The enzyme incorporation also led to significant changes in the equilibrium surface compressibility (in-plane elasticity), especially in liquid-expanded and liquid-condensed regions. The dynamic surface elasticity for phytase-containing interfaces was investigated using harmonic oscillation and axisymmetric drop shape analysis. The insertion of the enzyme at DPPG monolayers caused an increase in the dynamic surface elasticity at 30 mN m(-)(1), indicating a strong interaction between the enzyme and lipid molecules at a high-surface packing. Langmuir-Blodgett (LB) films containing 35 layers of mixed phytase-DPPG were characterized by ultraviolet-visible and fluorescence spectroscopy and crystal quartz microbalance nanogravimetry. The ability in detecting phytic acid was studied with voltammetric measurements.

This work presents a methodology for deriving a phase-domain transmission line representation based on time-domain fitting. A polynomial matrix in the discrete-time domain describes the resulting model. The robustness of the representation, its stability and passivity, is attained by imbedding a set of constraints in the solution of the fitting equations, which are solved using quadratic programming. Results demonstrating from transient simulations the features of the derived representation are presented for the case of an asymmetric, untransposed two-phase transmission line.

A hybrid approach for eutrophication assessment in estuarine and coastal ecosystems is presented. The ASSETS screening model ( http://www.eutro.org ) classifies eutrophication status into five classes: High (better), Good, Moderate, Poor and Bad (worse). This model was applied to a dataset from a shallow coastal barrier island system in southwest Europe (Ria Formosa), with a resulting score of Good. A detailed dynamic model was developed for this ecosystem, and the outputs were used to drive the screening model. Four scenarios were run on the research model: pristine, standard (simulates present loading), half and double the current nutrient loading. The Ria Formosa has a short water residence time and eutrophication symptoms are not apparent in the water column. However, benthic symptoms are expressed as excessive macroalgal growth and strong dissolved oxygen fluctuations in the tide pools. The standard simulation results showed an ASSETS grade identical to the field data application. The application of the screening model to the other scenario outputs showed the responsiveness of ASSETS to changes in pressure, state and response, scoring a grade of High under pristine conditions, Good for half the standard scenario and Moderate for double the present loadings. The use of this hybrid approach allows managers to test the outcome of measures against a set of well-defined metrics for the evaluation of state. It additionally provides a way of testing and improving the pressure component of ASSETS. Sensitivity analysis revealed that sub-sampling the output of the research model at a monthly scale, typical for the acquisition of field data, may significantly affect the outcome of the screening model, by overlooking extreme events such as occasional night-time anoxia in tide pools.

P956 Do a vendor-specific and a vendor-independent software for 3D echocardiographic analysis provide similar values for left ventricular volumes and ejection fraction? D. Muraru1; S. Mihaila2; E. Piasentini1; S. Casablanca1; P. Naso1; L. Puma1; D. Ermacora1; G. Zoppellaro1; S. Iliceto1; LP. Badano1 University of Padua, Department of Cardiac, Thoracic and Vascular Sciences, Padua, Italy; University of Medicine and Pharmacy Carol Davila, Bucharest, Romania

This protocol uses palladium chloride and bisamides as ligands for Suzuki cross-coupling reactions, in mild (25° for 2 h) aerobic conditions. This study was efficient for arylboronic acids and/or aryl bromides with activating or deactivating substituents in the ring with high yields (81–95%).

A simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine shows high activity for the Suzuki cross-coupling reaction of benzylic bromides and chlorides with aryl boronic acids. The reaction can be carried out at low catalyst loading (0.002–1 mol%) and under mild conditions (room temperature to 80 °C) furnishing diarylmethane derivatives in high yields (86–99%).

Langmuir monolayers at the air/water interface have been used for decades to mimic cell membranes in attempts to determine the mechanisms behind the physiological action of biologically-relevant molecules. In this review, we analyze the vast literature in the area, with the contents organized according to the type of molecules and materials, including peptides, proteins, polysaccharides, a variety of pharmaceuticals, and nanomaterials. The focus is placed on the correlation between the effects induced on the monolayers and the biological activity of the molecules and nanomaterials. Effects observed from these interactions can be coupling or adsorption and penetration of the molecules into the monolayer, which can be expanded, condensed or even disrupted. Changes in monolayer mechanical properties, for example, may be crucial for the biological activity. Whenever possible, we try to identify the forces prevailing in the interaction, which has been made possible with a combination of experimental techniques, including surface-specific spectroscopies, microscopies and rheological techniques, in addition to the traditional surface pressure and surface potential measurements. Overall, the mechanisms are governed by ionic electrostatic forces and hydrophobic interactions. Correlation may be straightforward, as in the cases of positively charged peptides and polymers whose antimicrobial activity is ascribed to electrostatic attraction with the negatively charged microbial membranes. Also general is the importance of hydrophobic interactions for the penetration into the membrane, which can be required for the biological action of, for example, polysaccharides. In other cases, correlation between monolayer properties and the physiological activity cannot be established precisely, as the latter may depend on a multitude of parameters that have not been possible to simulate with a simplified model such as that of a Langmuir monolayer. For nanomaterials, the emphasis is in relating interaction with the monolayers and their possible toxicity. Owing to the relevance of electrostatic and hydrophobic interactions, the effects on monolayers (and indeed toxicity) are found to depend largely on the coating or functionalization of the nanomaterials. (C) 2015 Elsevier B.V. All rights reserved.

A method for experimental data adjustment consisting of correction equations for the performance parameters of the refrigeration/heat pump vapor compression cycle, when operation conditions depart from those established in testing standards, is here presented. A basic thermodynamic model allowed for a methodology to be developed so as to correct vapor compression cycle performance to a desirable operating condition. Correction factor equations are proposed for refrigerant mass flow rate, compressor specific enthalpy gain and evaporator refrigeration effect, for situations when condensing pressure has not followed standards conditions or has not been properly controlled during experiments. The method was verified against experimental data from a vapor compression water-to-water heat pump with controlled condensing temperatures of 30oC, 40oC and 50oC. In spite of the purposely excessive correction, ±10oC, a relatively good smoothness, as well as a good agreement among all conversions, was obtained with the standardized points. The model was also applied to a refrigeration system running with water-SWCNT nanofluid (single walled carbon nanotube with water as the base fluid) as the secondary fluid. It contributed to a better discernment of the actual influence of the nanofluid in the system performance.

The relationship among daily sugar exposure, dental plaque composition and caries patterns in the primary dentition is not known. Three groups of 20 children (18–48 months old) were studied: (1) caries-free (CF), (2) presenting pit and fissure caries (PFC), and (3) with nursing caries (NC). Dental caries index (dmfs) was assessed and the frequency of daily sugar exposure (TS) and its forms were estimated by questionnaires. Fluoride (F), calcium (Ca), inorganic phosphorus (Pi), insoluble polysaccharide (IP) and mutans streptococci were quantified in dental plaque. The three groups of children were statistically different regarding daily sugar exposure. Concentrations of F, Ca and Pi were lower and the IP and mutans streptococci statistically higher in dental plaque from NC children than those from CF children. PFC children also showed statistically lower F and P levels in their plaque than CF children. Statistically significant correlations were found between IP, TS and dmfs from NC and PFC children. A statistically significant correlation between mutans streptococci in plaque from anterior teeth and dmfs for NC children was also observed. These results suggest that the dietary sugar experience changes the biochemical and microbiological composition of dental plaque, which could partly explain the different caries patterns observed in primary dentition.

The Perez irradiance model offers a practical representation of solar irradiance by considering the sky hemisphere as a three-part\ud geometrical framework, namely, the circumsolar disc, the horizon band and the isotropic background. Furthermore, the simplified Perez\ud diffuse irradiance model, commonly known as the Perez transposition model, is one of the most widely adopted models in tilted irradiance\ud modeling. Although the set of model coefficients reported by Perez et al. (1990) is considered to be at an asymptotic level of optimization,\ud later analyses have shown that coefficients which are adjusted to local conditions may perform better than the original set.\ud The model coefficients can be adjusted locally based on multiple datasets of diffuse and global irradiance on tilted and horizontal\ud planes. In this paper, we present a different approach to adjust the coefficients, by using only measurements of global irradiance on tilted\ud and horizontal planes from a tropical climate site, Singapore. A complete set of mathematical solutions to the inverse problem, i.e.,\ud irradiance transposition from tilt to horizontal, is also proposed. The data can then be used to generate irradiance maps from in-plane\ud irradiance measurements at photovoltaics (PV) systems. Such maps provide relevant information for PV grid integration.

Diacylglycerol acyltransferase 1 (DGAT1) is a microsomal membrane enzyme responsible for the final step in the synthesis of triacylglycerides. Although DGATs from a wide range of organisms have nearly identical sequences, there is little structural information available for these enzymes. The substrate binding sites of DGAT1 are predicted to be in its large luminal extramembranous loop and to include common motifs with acyl-CoA cholesterol acyltransferase enzymes and the diacylglycerol binding domain found in protein kinases.In this study, synthetic peptides corresponding to the predicted binding sites of DGAT1 enzyme were examined using synchrotron radiation circular dichroism spectroscopy, fluorescence emission and adsorption onto lipid monolayers to determine their interactions with substrates associated with triacylglyceride synthesis (oleoyl-CoA and dioleoylglycerol). One of the peptides, Sit1, which includes the FYxDWWN motif common to both DGAT1 and acyl-CoA cholesterol acyltransferase, changes its conformation in the presence of both substrates, suggesting its capability to bind their acyl chains. The other peptide (Sit2), which includes the putative diacylglycerol binding domain HKWCIRHFYKP found in protein kinase C and diacylglycerol kinases, appears to interact with the charged headgroup region of the substrates. Moreover, in an extended-peptide which contains Sit1 and Sit2 sequences separated by a flexible linker, larger conformational changes were induced by both substrates, suggesting that the two binding sites may bring the substrates into close proximity within the membrane, thus catalyzing the formation of the triacylglyceride product.

The surface activity of the poly–[ block (ethylene oxide)]–poly [ block (propylene oxide)]–poly [ block (ethylene oxide)] copolymers (EO) x –(PO) y –(EO) x adsorbed together with dihexadecyl phosphoric acid (DHP), a synthetic phospholipid, is analyzed from their surface pressure and surface potential isotherms. The block copolymers of (EO) x –(PO) y –(EO) x with variable molecular weight (1100–14 000) were dissolved in the subphase for DHP monolayers. The concentration of the copolymers within the aqueous subphase were selected to render an initial surface tension of 60 mN/m. The simultaneous adsorption of the copolymer and DHP is attested by the observation of a liquid expanded state at large areas, absent for pure DHP monolayers. Above some critical surface pressure all copolymers cited above are expelled from the interface. The surface potential isotherms, which give information on the component of the molecular dipole moment normal to the plane of the monolayer, are interpreted in terms of changes in the copolymer conformation as well as in terms of the copolymer desorption from the air–liquid interface. For an equal hydrophobic/hydrophilic ratio, the size of the chains or molecular weight is decisive in the mechanism of the copolymer expulsion from the air–liquid interface.

This in vitro study aimed at evaluating the efficacy of a CO2 laser (10.6 µm) alone or combined with acidulated phosphate fluoride (APF) on the inhibition of lesion progression in primary enamel. The specimens were treated with/without CO2 laser and/or APF and submitted to pH cycling. Microhardness analysis was performed and the enamel mineral loss values were obtained. The groups treated with laser and/or APF presented lower mineral loss when compared to the control group (p < 0.05). Laser irradiation alone or combined with APF decreased lesion progression in primary enamel. However, the combined treatment did not show any significant additional effect.

A simple methyl salicylate-derived bisamide is used as novel ligand in Suzuki cross-coupling reactions.

Gingivo-buccal oral squamous cell carcinoma (OSCC-GB), an anatomical and clinical subtype of head and neck squamous cell carcinoma (HNSCC), is prevalent in regions where tobacco-chewing is common. Exome sequencing (n=50) and recurrence testing (n=60) reveals that some significantly and frequently altered genes are specific to OSCC-GB (USP9X, MLL4, ARID2, UNC13C and TRPM3), while some others are shared with HNSCC (for example, TP53, FAT1, CASP8, HRAS and NOTCH1). We also find new genes with recurrent amplifications (for example, DROSHA, YAP1) or homozygous deletions (for example, DDX3X) in OSCC-GB. We find a high proportion of C>G transversions among tobacco users with high numbers of mutations. Many pathways that are enriched for genomic alterations are specific to OSCC-GB. Our work reveals molecular subtypes with distinctive mutational profiles such as patients predominantly harbouring mutations in CASP8 with or without mutations in FAT1. Mean duration of disease-free survival is significantly elevated in some molecular subgroups. These findings open new avenues for biological characterization and exploration of therapies., Gingivo-buccal oral squamous cell carcinoma (OSCC-GB) is the leading cancer among males in India. Here, the authors carry out exome sequencing and recurrence testing in patients with OSCC-GB and highlight genes and biological pathways associated with the disease.

It is well known that the efficiency of PV modules decreases with increasing module temperatures. Many studies have paid attention to the development and validation of heuristic models to calculate the PV module temperature in higher latitudes, however only a few focus on the thermal behaviour of PV modules in tropical regions of the world, where constantly high temperatures prevail. Also, little is known about the effect of including wind speed in these thermal models. This study evaluates three of such models - one that excludes wind, and two others including the wind influence - using hourly data for two tropical locations. Results show that the average hourly wind speeds in Singapore and Jayapura (Indonesia) are low and therefore the influence of the wind on the PV module temperature is minor. The three evaluated models produce about the same results with RMSE between 1.5-3.8 °C during daytime, which corresponds to a deviation in power output in the range of 0.3-1.6 %, depending on the PV module technology.

Carrageenans have unique properties in the pharmaceutical and food industries that involve interactions with lipid interfaces, which may be accessed if surface chemistry techniques are employed. The interaction between three different types of carrageenans with dipalmitoylphosphatidylcholine (DPPC) was investigated using Langmuir monolayers as biointerface models. With a combination of data on Surface Pressure–Area Isotherms and Polarization Modulation Infrared Reflection-Absorption Spectroscopy (PM-IRRAS), the effect of different fractions on DPPC monolayers was compared by considering the chemical and structural differences as well as the anticoagulant activity of each fraction. Thus, a model is proposed in which carrageenans can encompass interactions that are maximized due to geometrical adaptations on behalf of the interactions between polysaccharide sulfate groups and lipid polar heads.

Nanomaterials such as carbon nanotubes (CNTs) and nanoparticles have received enormous attention in analytical areas for their potential applications as new tools for biotechnology and life sciences. Most of these possible applications involve the use of CNTs and related materials as vehicles for drug delivery and/or gene therapy. In this study, we introduce a methodology to evaluate the interactions between CNTs/dendrimers nanoconjugates and phospholipid biomembrane models, using the Langmuir film balance technique. Our main goal was to elucidate the action of engineered nanomaterials in cell membranes, at the molecular level, using a membrane model system. The penetration of single-walled carbon nanotubes (SWCNTs)/polyamidoamine dendrimer nanocomplexes into dipalmitoylphosphatidylcholine monolayers was pronounced, as revealed by adsorption kinetics and surface pressure measurements. These findings suggest that SWCNTs were able to interact even at high surface pressure values, ∼30 mN/m. Therefore, the results confirm that the presence of the nanomaterial affects the packing of the synthetic membranes. We believe the methodology introduced here may be of great importance for further nanotoxicity studies.

The asymmetric unit of the title compound, C16H16N2O4, contains one half-molecule, the whole molecule being generated by an inversion center located at the mid-point of the C—C bond of the central ethane group. An intramolecular O—H...O hydrogen bond forms anS(6) ring motif. In the crystal, molecules are connectedviaN—H...O hydrogen bonds, generating infinite chains along [1-10].

The molecular mechanisms responsible for protein structural changes in the central nervous system leading to Alzheimer's disease are unknown, but there is evidence that a family of proteins known as septins may be involved. Septins are a conserved group of GTP-binding proteins which participate in various cellular processes, including polarity determination and membrane dynamics. SEPT1, SEPT4, and SEPT2 have been found in deposits known as neurofibrillary tangles and glial fibrils in Alzheimer's disease. In this study, we provide molecular-level information for the interaction of SEPT2 with Langmuir monolayers at the air/water interface, which are used as simplified membrane models. The high surface activity of SEPT2 causes it to adsorb onto distinct types of lipid Langmuir monolayers, namely dipalmitoylphosphatidylcholine and PtdIns(4,5)P2. However, the interaction with PtdIns(4,5)P2 is much stronger, not only leading to a higher adsorption, but also to SEPT2 remaining inserted within the membrane at high surface pressures. Most importantly, in situ polarization-modulated infrared reflection absorption spectroscopy results indicated that the native secondary structure of SEPT2 is preserved upon interacting with PtdIns(4,5)P2, but not when dipalmitoylphosphatidylcholine is at the air/water interface. Taken together, the results presented here suggest that the interaction between SEPT2 and the cell membrane may play an important role in the assembly of SEPT2 into amyloid-like fibers.

This study evaluated the antibacterial activity of Rosmarinus officinalis extract and its potential for disinfecting guttapercha (GP) cones. In the first experiment, a hydro-alcoholic extract of Rosmarinus officinalis (leaves) in a dilution ratio of 10% m/v was tested against Enterococcus faecalis by using the disk diffusion method. Positive and negative controls were 70% cereal alcohol and antibiotics, respectively. The procedures were performed in triplicate, and the diameters of the zones of growth inhibition were measured with a caliper after 24 h at 37 degrees C. In the second experiment, the disinfection procedures were evaluated on GP cones artificially contaminated with Enterococcus faecalis. The R. officinalis extract was compared with 2% chlorhexidine digluconate and 2.5% sodium hypochlorite, using a direct exposure test (5 min treatment). Sterilized and non-disinfected cones were used as negative and positive controls, respectively. After 24 h of incubation, bacterial counts were taken. For both experiments, the data were statistically analyzed by Kruskall-Wallis and Tukey's tests (p0.05). The plant extract produced zones of inhibition comparable to those of tested antibiotics. Significant GP cone disinfection was verified with all disinfectant solutions, with no significant difference between them. R. officinalis extract showed bactericidal effect on Enterococcus faecalis and capacity to disinfect GP cones contamined with it.

OBJETIVOS: avaliar a positividade sorológica para doença celíaca em um grupo de adolescentes e adultos jovens da cidade do Recife, Nordeste do Brasil. MÉTODOS: a amostra foi composta por estudantes matriculados nos cursos de graduação do Centro de Ciências da Saúde da Universidade Federal de Pernambuco. Os estudantes foram submetidos à coleta de sangue para pesquisa sorológica do anticorpo antitransglutaminase tecidual humana e responderam a questionário sobre sintomas e condições mórbidas associadas à doença celíaca. O anticorpo antitrans-glutaminase foi pesquisado por técnica de Elisa, considerando-se positivos valores acima de 10 U/mL, conforme estabelecido pelo fabricante. Nos pacientes que tiveram sorologia positiva para o anticorpo antitransglutaminase realizou-se a sorologia para o anticorpo antiendomíseo, por imunofluorescência indireta, utilizando kit comercialmente disponível. RESULTADOS: seiscentos e oitenta e três universitários participaram da pesquisa. Os estudantes tinham entre 18 e 30 anos e mediana de idade de 21 anos. O anticorpo antitransglutaminase foi positivo em 12/683, soroprevalência de 1,76% (IC95%: 0,95-3,13%). O anticorpo antiendomíseo foi realizado em 11 amostras e reagente em quatro. Oito estudantes com sorologia positiva tinham sintomas e/ou condições mórbidas associadas à doença celíaca. CONCLUSÕES: a elevada presença de anticorpos anti-transglutaminase encontrada neste estudo é semelhante a da Europa e Estados Unidos da América, sugere a possibilidade da triagem sorológica mesmo em populações consideradas de baixo risco. OBJECTIVES: to evaluate serum for celiac disease in a group of adolescents and young adults in the city of Recife, in the Northeast region of Brazil. METHODS: the sample was made up of students enrolled on undergraduate courses at the Center for Health Sciences of the Federal University of Pernambuco. A blood sample was taken from the students to test their serum for the human tissue antitransglutaminase antibody and they were asked to complete a questionnaire on the symptoms and morbid conditions associated with celiac disease. THE antitransglutaminase was identified using the Elisa technique, taking positive values to be those above 10 U/mL, as recommended by the manufacturer. Patients who tested positive for the antitransglutaminase antibody were subsequently tested for the antiendomysial antibody, by indirect immunofluorescence, using the commercially available kit. RESULTS: six hundred and eight-three university students took part in the study. They were aged between 18 and 30 years, with a mean age of 21 years. The antitransglutaminase antibody was found in 12/683, a prevalence of 1.76% (CI95%: 0.95-3.13%). The antiendomysial antibody test was carried out in eleven these samples and the reagent in four. Eight students tested positive and/or had morbid conditions associated with celiac disease. CONCLUSIONS: the high levels of anti-transglutaminase antibodies found in this study were similar to those found in Europe and the United States suggesting that serological triage can be carried out even in populations considered to be low risk.

The diagnosis of a non-surgical cause of delayed passage of meconium in a neonate may be challenging to the pediatric surgeon. The usefulness of determining trypsin activity (TA) in stool and duodenal aspirate for the diagnosis of cystic fibrosis (CF) and the existence of an entity called transient deficiency of trypsin (TTD) was assessed in 49 neonates over a 14-month period. TA was determined by a gelatin liquefaction technique. An absence of TA was considered if gelatin liquefaction was seen at a dilution of less than 1:100. Neonates with negative activity in both samples were started on supplementary pancreatic enzymes (pancreatin) for 1 month. TA was retested in the stool after stopping pancreatin for 1 week. Neonates with a return of TA were considered to have TTD; those who showed persistent TA deficiency at re-evaluation were investigated for CF by sweat iontophoresis. Twenty-one neonates had negative TA (in 1 only stool was tested); 13 could be re-evaluated (4 died, 4 were lost to follow-up). Nine were found to have TTD as a stool or duodenal sample showed the presence of TA; 3 of 4 patients with persistent negative TA were confirmed to have CF. One patient with normal sweat chloride is awaiting genetic studies. Determination of TA by gelatin liquefaction is a simple, rapid, inexpensive, and reliable (sensitivity 100%, negative predictive value 100%) means to differentiate non-surgical causes of intestinal obstruction such as neonatal and postoperative TTD and CF.

This process works without isolation after the first arylation and without additional catalyst loading.

This article addresses the interactions of the synthetic antimicrobial peptide dermaseptin 01 (GLWSTIKQKGKEAAIAAA- KAAGQAALGAL-NH(2) , DS 01) with phospholipid (PL) monolayers comprising (i) a lipid-rich extract of Leishmania amazonensis (LRE-La), (ii) zwitterionic PL (dipalmitoylphosphatidylcholine, DPPC), and (iii) negatively charged PL (dipalmitoylphosphatidylglycerol, DPPG). The degree of interaction of DS 01 with the different biomembrane models was quantified from equilibrium and dynamic liquid-air interface parameters. At low peptide concentrations, interactions between DS 01 and zwitterionic PL, as well as with the LRE-La monolayers were very weak, whereas with negatively charged PLs the interactions were stronger. For peptide concentrations above 1 µg/ml, a considerable expansion of negatively charged monolayers occurred. In the case of DPPC, it was possible to return to the original lipid area in the condensed phase, suggesting that the peptide was expelled from the monolayer. However, in the case of DPPG, the average area per lipid molecule in the presence of DS 01 was higher than pure PLs even at high surface pressures, suggesting that at least part of DS 01 remained incorporated in the monolayer. For the LRE-La monolayers, DS 01 also remained in the monolayer. This is the first report on the antiparasitic activity of AMPs using Langmuir monolayers of a natural lipid extract from L. amazonensis.

This article presents an approach that couples coastal ecosystem modeling with integrated environmental assessment methodologies to support coastal management. The focus is to support the development of an ecosystem approach to aquaculture management including interactions with watershed substance loading. A Chinese bay, with intense aquaculture and multiple catchment uses, and where significant modeling efforts were undertaken is used as a case study. The ecosystem model developed for this bay is used to run scenarios that test the local management strategy for nutrient reduction. The corresponding ecological and economic impacts of the managers’ scenarios are analyzed by means of the Differential Drivers-Pressure-State-Impact-Response (ΔDPSIR) analysis. Emphasis is given to the analysis of the eutrophication process in the bay including present eutrophic condition and the expected changes due to the simulated scenarios. For this purpose, the Assessment of Estuarine Trophic Status (ASSETS) screening model is a valuable tool to interpret and classify the data and model outputs regarding eutrophication condition and to evaluate the manageable level of the nutrient loading entering in the bay.