361 research outputs found
Spectrofluorometric characteristics of fluorescent dissolved organic matter in a surface microlayer in the Southern Baltic coastal waters
This paper presents results of characterization of Dissolved Organic Matter (DOM) using fluorescence spectroscopy in the surface microlayers (SML) and subsurface layers (SS) in the Baltic Sea. Samples for spectroscopic measurements were collected during five research cruises in April/May and October 2013 and 2014 in a surface microlayer and a subsurface layer at a depth of 1 m along two transects from the river outlets to the open sea. The first transect was located from the Vistula River outlet to the Gdansk Deep and the second transect was located ´ from the Łeba River outlet to Słupsk Furrow. Results indicated that DOM fluorescence intensity in the SML is higher by 20% compared to the SS. The Humification Index, HIX values were lower in SML than SS by 13%. That indicates that SML is depleted in molecules with high molecular weight and higher aromaticy. The inverse relationship of fluorescence intensity of dominant peaks with salinity both in SML and SS suggests that FDOM variability is regulated mostly by terrestrial DOM input
Relationships between colored dissolved organic matter and dissolved organic carbon in different coastal gradients of the Baltic Sea
Experimental evidence of high pressure decoupling between charge transport and structural dynamics in a protic ionic glass-former
In this paper the relaxation dynamics of ionic glass-former acebutolol hydrochloride (ACB-HCl) is studied as a function of temperature and pressure by using dynamic light scattering and broadband dielectric spectroscopy. These unique experimental data provide the first direct evidence that the decoupling between the charge transport and structural relaxation exists in proton conductors over a wide T-P thermodynamic space, with the time scale of structural relaxation being constant at the liquid-glass transition (τα = 1000 s). We demonstrate that the enhanced proton transport, being a combination of intermolecular H+ hopping between cation and anion as well as tautomerization process within amide moiety of ACB molecule, results in a breakdown of the Stokes-Einstein relation at ambient and elevated pressure with the fractional exponent k being pressure dependent. The dT g /dP coefficient, stretching exponent βKWW and dynamic modulus E a /ΔV # were found to be the same regardless of the relaxation processes studied. This is in contrast to the apparent activation volume parameter that is different when charge transport and structural dynamics are considered. These experimental results together with theoretical considerations create new ideas to design efficient proton conductors for potential electrochemical applications
Poly-Gamma-Glutamic Acid (γ-PGA)-based encapsulation of Adenovirus to evade neutralizing antibodies.
In recent years, there has been an increasing interest in oncolytic adenoviral vectors as an alternative anticancer therapy. The induction of an immune response can be considered as a major limitation of this kind of application. Significant research efforts have been focused on the development of biodegradable polymer poly-gamma-glutamic acid (γ-PGA)-based nanoparticles used as a vector for effective and safe anticancer therapy, owing to their controlled and sustained-release properties, low toxicity, as well as biocompatibility with tissue and cells. This study aimed to introduce a specific destructive and antibody blind polymer-coated viral vector into cancer cells using γ-PGA and chitosan (CH). Adenovirus was successfully encapsulated into the biopolymer particles with an encapsulation efficiency of 92% and particle size of 485 nm using the ionic gelation method. Therapeutic agents or nanoparticles (NPs) that carry therapeutics can be directed specifically to cancerous cells by decorating their surfaces using targeting ligands. Moreover, in vitro neutralizing antibody response against viral capsid proteins can be somewhat reduced by encapsulating adenovirus into γ-PGA-CH NPs, as only 3.1% of the encapsulated adenovirus was detected by anti-adenovirus antibodies in the presented work compared to naked adenoviruses. The results obtained and the unique characteristics of the polymer established in this research could provide a reference for the coating and controlled release of viral vectors used in anticancer therapy.This work was funded by the Ministry of Higher Education and Scientific Research (Iraq). This work was also partially funded by the Research Investment Fund, University of Wolverhampton (Wolverhampton, United Kingdom) and the Italian Ministry of University and Research (MIUR)
Mechanisms generating long-range correlation in nucleotide composition of the Borrelia burgdorferi genome
Abstract We have analysed protein coding and intergenic sequences in the Borrelia burgdorferi (the Lyme disease bacterium) genome using di erent kinds of DNA walks. Genes occupying the leading strand of DNA have signiÿcantly di erent nucleotide composition from genes occupying the lagging strand. Nucleotide compositional bias of the two DNA strands re ects the aminoacid composition of proteins. 96% of genes coding for ribosomal proteins lie on the leading DNA strand, which suggests that the positions of these as well as other genes are non-random. In the B. burgdorferi genome, the asymmetry in intergenic DNA sequences is lower than the asymmetry in the third positions in codons. All these characters of the B. burgdorferi genome suggest that both replication-associated mutational pressure and recombination mechanisms have established the speciÿc structure of the genome and now any recombination leading to inversion of a gene in respect to the direction of replication is forbidden. This property of the genome allows us to assume that it is in a steady state, which enables us to ÿx some parameters for simulations of DNA evolution. c 1999 Elsevier Science B.V. All rights reserved. PACS: 87.14.G; 05.10-a Keywords: Long-range correlation; Replication; Transcription * Corresponding author. Fax: +48-71-3252151. E-mail addresses: [email protected] (S. Cebrat), [email protected] (M.R. Dudek) 0378-4371/99/$ -see front matter c 1999 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 8 -4 3 7 1 ( 9 9 ) 0 0 3 4 5 -3 104 P. Mackiewicz et al. / Physica A 273 (1999) 103-11
Solvent contribution to the stability of a physical gel characterized by quasi-elastic neutron scattering
The dynamics of a physical gel, namely the Low Molecular Mass Organic Gelator
{\textit Methyl-4,6-O-benzylidene- -D-mannopyranoside (-manno)}
in water and toluene are probed by neutron scattering. Using high gelator
concentrations, we were able to determine, on a timescale from a few ps to 1
ns, the number of solvent molecules that are immobilised by the rigid network
formed by the gelators. We found that only few toluene molecules per gelator
participate to the network which is formed by hydrogen bonding between the
gelators' sugar moieties. In water, however, the interactions leading to the
gel formations are weaker, involving dipolar, hydrophobic or
interactions and hydrogen bonds are formed between the gelators and the
surrounding water. Therefore, around 10 to 14 water molecules per gelator are
immobilised by the presence of the network. This study shows that neutron
scattering can give valuable information about the behaviour of solvent
confined in a molecular gel.Comment: Langmuir (2015
Field testing, validation and optimization report
The COMMON SENSE project has been designed and planned in order to meet the general and specific scientific and technical objectives mentioned in its Description of Work (page 77).
As the overall strategy, the 11 work packages (WPs) of the work plan were grouped into 3 key phases: (1) RD basis for cost-effective sensor development , (2) Sensor development, sensor web platform and integration, and (3) Field testing. In the first two phases, partners involved in WP1 and WP2 have provided a general understanding and integrated basis for a cost effective sensors development. Within the following WPs 4 to 8 the new sensors were created and integrated into different identified platforms. During the third phase of field testing (WP9), partners have deployed precompetitive prototypes at chosen platforms (e.g. research vessels, oil platforms, buoys and submerged moorings, ocean racing yachts, drifting buoys). Starting from August 2015 (month 22; task 9.2), these platforms have allowed the partnership to test the adaptability and performance of the in-situ sensors and verify if the transmission of data is properly made, correcting deviations.
In task 9.1 all stakeholders identified in WP2 have been contacted in order to agree upon a coordinated agenda for the field testing phase for each of the platforms. Field testing procedures (WP2) and deployment specificities, defined during sensor development in WPs 4 to 8, have been closely studied by all stakeholders involved in field testing activities in order for everyone to know their role, how to proceed and to provide themselves with the necessary material and equipment (e.g. transport of instruments). All this information have provided the basis for designing and coordinating field testing activities.
Subsequently, the available new sensors have been tested since August 2015 till mid-October of the current year (2016) as part of task 9.2, following the indications defined in D9.1, such as the intercomparison of the new sensors with commercial ones, when possible.
The availability of new sensors was quite different in time starting with the first tests in September and October 2015 on noise, nutrient and heavy metals sensors and closing with pCO2 in late September 2016.
Sensors are technically fully described in the deliverables of WPs 3 to 8 and are here just mentioned where necessary. For further details, please consider those reports.
Objectives and rationale
The protocols prepared in D9.1 have been verified during the field testing activities of the innovative sensors on platforms. These can be summarized into 3 categories: (1) Research vessels (regular cruises); (2) Fixed platforms; (3) Ocean racing yachts. An exhaustive analysis of the different data obtained during field testing activities has been carried on in order to set possible optimization actions for prototypes design and performances. The data from each platform have been analyzed to verify limits and optimal installations or possible improvements. Finally a set of possible optimization actions has been defined. Data and observations collected during the course of field testing have been used to iteratively optimize the design and performance of the precompetitive prototypes
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