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The present paper is aiming to give an example of environmental management implementation at academic level, in German universities. The study was part the European Union Socrates Program, Erasmus Curricula Development Dissemination Project that gathered European universities with environmental related curricula. The experience exchange among the partner institutions made possible lessons learned from each institution expertise in this domain. [ABSTRACT FROM AUTHOR]

As ESP trainers, we are increasingly aware that our learners have a specific purpose in learning English. Consequently, our aim is to develop a syllabus based on their particular needs and professional requirements. Our course objectives should thus focus on developing skills, cultural awareness and communicative effectiveness. Therefore, language accuracy is no longer a priority particularly if we take into account time restrictions (short number of hours) as well as other limitations (great number of students, various levels of English, etc.) and challenges (knowledge of the field, jargon) that the Business trainer has to deal with on a regular basis. It has long been argued that learning the vocabulary related to a particular job is fundamental to ESP lessons. However, as Adrian Tenant (2015) rightfully notes, standard vocabulary knowledge may actually prove useless when students are faced with real life situations. He stresses on the fact that students must be taught how to learn, develop and use their knowledge on the long term. The aim of this paper is to identify and describe some key skills that business English students need to acquire in order to set the basis of their further development. The main topics which may be included in the Business English syllabus will be discussed and relevant examples will be provided. [ABSTRACT FROM AUTHOR]

Abstract: In this paper was studied the uranyl ions biosorption on three types of alga: Nostok linckia, Porphyridium cruentum and Spirulina platensis. These ions were supplied either from a pure solution of uranyl nitrate, or after leaching process of uranium ore, or from the sludge resulting in the output of pure UO2 technology. It was investigated the retention degree versus contact time and afterwards the Langmuir and Freundlich biosorption isotherms of uranyl ions on the three alga types. The retention of ions on alga was proved through FTIR spectra plotted before and after biosorption processes. From the experimental data it was found that regardless of origin of uranyl ions, the retention degree on alga decreased in the series. [Copyright &y& Elsevier]

The present paper deals with the retention of U(IV) and U(VI) species, both individually and in 1 :1 mixtures, on some ion-exchange resins of the normal DGA (N,N’,N’-tetra-n-octyldiglycolamide), TEVA- [trialkyl methyl-ammonium nitrate (or chloride)] and UTEVA-type (dipentyl pentylphosphonate), in different experimental conditions. The degree of retention, distribution constant, as well as enthalpy and entropy values which characterize the adsorption of uranium ions on these resins were calculated. By means of Langmuir relation, taking into account the experimental data, the maximum adsorption capacity, Langmuir constant and Gibbs free energy values for the studied processes are established. [ABSTRACT FROM AUTHOR]

Immunization of transgenic mouse models of Alzheimer disease using amyloid-β peptide (Aβ) reduces both the Alzheimer disease-like neuropathology and the spatial memory impairments of these mice. However, a therapeutic trial of immunization with Aβ[sub 42] in humans was discontinued because a few patients developed significant meningo-encephalitic cellular inflammatory reactions. Here we show that beneficial effects in mice arise from antibodies selectively directed against residues 4-10 of Aβ[sub 42], and that these antibodies inhibit both Aβ fibrillogenesis and cytotoxicity without eliciting an inflammatory response. These findings provide the basis for improved immunization antigens as well as attempts to design small-molecule mimics as alternative therapies. [ABSTRACT FROM AUTHOR]

This paper deals with a study on the retention of radioactive ions 65 Zn 2+ from diluted waste solutions by the hydrophytic plants Lemna minor , Elodea canadensis , Pistia stratiotes and Riccia fluitans. The bioaccumulation degree decreases in the following order: Riccia fluitans≈Pistia stratiotes≥Lemna minor>Elodea canadensis The possibility to improve the bioaccumulation degree varying the temperature and the solution pH, in the absence of other cations, has been studied. The thin layer radiochromatography method has been used and it proved that the saccharides and lipids are the biochemical fractions responsible for the 65 Zn 2+ retention. [ABSTRACT FROM AUTHOR]

This paper deals with a study on the bioaccumulation of uranyl ions resulted from residual effluents by means of some microbiological collectors: Scenedesmus quadricauda, Anabaena karakumica, Calothrix brevissima, Penicillinium sp, as well as the Glucide extract of Porphyridium cruentum, under various experimental conditions. The retaining degree of the bioaccumulated uranyl ions, as well as the leaching degree, in HCl and H2O media, of the same ions previously retained on algae were established. The retaining degree decreases in the serie: Scenedesmus quadricauda >Anabaena karakumica >Penicillinium sp>Calothrix brevissima. The leaching effect of bioaccumulated uranyl ions is higher in hydrochloric acid than in water. [ABSTRACT FROM AUTHOR]

The nucleation process of 65Zn(OH)2, 65Zn3(PO4)2, and 51CrPO4 crystals in gelatin and agar was studied by using radioactive tracers. The diffusion rate, constants for 65Zn2+ and 51Cr3+ cations through gel, and the reaction rate constants of nucleation process as well as the beginning time of crystal appearance were established. It was found that the reaction rate constant of the low-soluble crystal is higher, and consequently, in a given colloidal medium this parameter varies as follows: k * Zn(PO4)2> k * Zn(OH) 2> k * CrPO 4 [ABSTRACT FROM AUTHOR]

Modification of the physico-mechanical properties of films made of biologically compatible polymers, with urethane groups, complexed with metallic ions from the s-block (Soft Block), have been investigated according to cation nature and photochemical irradiation time. Strain at the break, remnant elongation, elasticity modulus and resistance at the break were the main physico-mechanical properties measured. Experiments were carried out by irradiation with ultraviolet light, on solid film, under condition of accentuated degradation. Ions of both alkaline metals and alkaline-earth metals in the first step of irradiation improve the physico-mechanical properties. But in the middle of the investigated range they strongly decrease, concomitantly with the appearance of some deep photochemical induced structural modifications in the structure of the investigated polyesterurethane. [ABSTRACT FROM AUTHOR]

The present study reports the U(VI) uptake from solution on a Ti-rich Egyptian black sand, showing that the crystal surfaces exhibit a marginal influence to the total process of U(VI) uptake onto Ti-containing micro- and mesoporous silicate materials. The results were evaluated using Lagergren first order equation and the apparent thermodynamic parameters of uranium uptake onto the considered materials were calculated. [ABSTRACT FROM AUTHOR]

A review is presented to show the advantages involved in the use of some new spectrophotometric cyanide (CN) assays, which are highly sensitive and selective, quick and affordable. Among these, the ninhydrin-based assay, the method based on CN reaction with resorcinol, as well as the Berthelot reaction were found to be highly selective. The old Aldridge 1 method, based on the formation of cyanogen bromide and its subsequent reaction with pyridine and benzidine to form a highly-colored polymethine chromophore is still in use, although recent assays using isonicotinic acid-sodium barbiturate are safe, selective, and sensitive (with a detection limit of 0.005-0.01 mg L-1 CN). Ninhydrin-based procedures are suitable to detect low trace amounts of CN with a molar absorptivity below 2.2 × 105 L M-1 cm-1 and detection limit of less than 1 ng cm-1 CN. The sensitivity, specificity, and reliability of the investigated methods were compared and the most appropriate protocol for a given analytical problem described. [ABSTRACT FROM AUTHOR]

Studies to test the noxious effect of mercury ions on wheat germination and seedling growth showed that germination rate, shoot length, and fresh weights varied as a function of their concentration in the treatment solutions. At the same concentration, the radioactive mercury proved to be more harmful to the living seeds and seedlings. The detoxification action of glutathione for both radioactive and non-radioactive mercury was also followed. After a seven-day period of germination in the presence of the investigated compounds, the wheat plantlets were cut from the seeds, and their height, weight, and residual radioactivity were measured. The shoot length decreased from 8.1 (blank) to 4.6 cm (non-radioactive mercury) or even to 2.5 cm (203Hg), while glutathione had both an anti-toxic and an anti-radiotoxic effect (6.4 and 6.0 cm, respectively). The root weight of the lot decreased from 1.7 to 0.7 g and 0.4 g, respectively, while glutathione showed a healing action (1.5 and 1.7 g). The radioactive ions accumulated especially in roots (35.5 %), and less in shoots (11.2 %). Results were statistically validated. [ABSTRACT FROM AUTHOR]

The sorption behavior of U(VI) and Th(IV) from simulated waste solutions on a zeolitic volcanic tuff from Nereju (Vrancea, Romania) has been studied in the absence of the ionic competition as a function of contact time, radioactive ions concentration, temperature and pH using a batch mode technique. The effect of the above-mentioned parameters on the sorption efficiency was discussed. The apparent thermodynamic parameters of the sorption of uranium and thorium onto the considered volcanic tuff were calculated, showing that the process is endothermic and higher temperatures favor the sorption process. [ABSTRACT FROM AUTHOR]

The sorption of 60Co2+, 115mCd2+ and 203Hg2+ from diluted solutions (as analogues for radioactive waste waters) on ETS-4 microporous titanosilicate was studied at 277, 293, 313 and 333 K by measuring the sorption kinetics using a batch-method. The sorption of these radiocations was compared by means of the distribution coefficient and of the sorption capacity. The maximum sorption capacities follow the order: 203Hg2+>115mCd2+³60Co2+. The thermodynamic functions of the sorption processes have been estimated. The increase of the absolute value of D G° with increasing temperatures shows that higher temperatures favor ionic exchange. [ABSTRACT FROM AUTHOR]

The living Lemna minor vascular plant and two different sorbents obtained by chemical treatment of this plant were tested to study the removal process of 60 Co 2+ , 65 Zn 2+ and 55+59 Fe 3+ from low radioactive wastewaters. The most effective sorbent was the protonated biomass, indicating the decisive contribution of the complexation process in the assembly of the uptake mechanisms. The uptake performance of the biosorbent obtained from the L. minor can be increased with ~20% by treatment with 0.1 N HNO 3 . Concerning the metabolically active mechanism, it can be notice the slow elimination of 65 Zn 2+ and the continuously increase of 55+59 Fe 3+ uptake degree. The Na 2 CO 3 generated in situ in systems participates to a double exchange reaction with the metallic cations during the uptake. 60 Co 2+ , 65 Zn 2+ and 55+59 Fe 3+ radiocations prefer for coordination N-donor ligands at the expense O-donors ones. [ABSTRACT FROM AUTHOR]

The newly developed immobilized enzyme reactors (IMERs) with proteolytic enzymes chymotrypsin, trypsin or papain were used for specific fragmentation of high molecular-mass and heterogeneous glycoproteins immunoglobulin G (IgG) and crystallizable fragment of IgG (Fc). The efficiency of splitting or digestion were controlled by RP-HPLC. The specificity of digestion by trypsin reactor was controlled by MS. IMERs (trypsin immobilized on magnetic microparticles focused in a channel of magnetically active microfluidic device) was used for digestion of the whole IgG molecule. The sufficient conditions for IgG digestion in microfluidic device (flow rate, ratio S:E, pH, temperature) were optimized. It was confirmed that the combination of IMERs with microfluidic device enables efficient digestion of highly heterogeneous glycoproteins such as IgG in extremely short time and minimal reaction volume. [Copyright &y& Elsevier]

Amyloid plaques associated to Alzheimer’s disease present a high content of zinc ions. We previously showed that the N-terminal region of the amyloid peptide Aβ constitutes an autonomous zinc-binding domain. This region encompasses the previously identified epitope Aβ(4–10) targeted by antibodies capable to reduce amyloid deposition, but the influence of Aβ/Zn binding on the epitope recognition remains unknown. We demonstrate here the effect of Zn2+ ions on the recognition of peptides sharing the sequence of the Aβ N-terminal domain, by two monoclonal antibodies recognizing the β-amyloid(4–10) epitope. The presence of Zn2+, but not of other cations, increased the recognition of the (1–16) peptide, while it was without effect on the recognition of the (1–10) peptide. These findings show a zinc-induced conformational change of the (1–16)-N-terminal region of Aβ, which results in a better accessibility of the Aβ(4–10) epitope to the anti-Aβ antibodies, and suggest a role of zinc in epitope-based vaccination approaches. [Copyright &y& Elsevier]

The microporous titanosilicate ETS-10 synthesized from gel with following molar composition: 1.0 Na2O: 1.49 SiO2 : 0.2 TiO2 : 0.6 KF : 1.28 HCl : 39.5 H2O was subjected to sorption of radioactive cations 115Cd2+, 204Hg2+, 60Co2+ and 137Cs+ (M) from aqueous solution, in the absence of ionic competition. The uptake of these cations on the ETS-10 was compared by means of the distribution coefficient (Kd) versus contact time and sorption capacity (R) at equilibrium. The FT-IR spectra of M-ETS-10 sorption products exhibit a modification of the absorption band, principally at 381 cm-1. [ABSTRACT FROM AUTHOR]