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Absorbent hygiene products contain a super absorbent polymer (SAP) as one of the main constituents that is not easily biodegraded or recycled. Currently, the vast majority of the material is landfi...

Despite the important role of the nerve growth factor in the survival and maintenance of neurons in ischemic stroke, data regarding the relationships between variations in the encoding gene and stroke are lacking. In the present study, we evaluated the association of the functional polymorphisms in NGF (rs6330) and NGFR (rs2072446 and rs734194) genes with ischemic stroke in an Armenian population. In total, 370 unrelated individuals of Armenian nationality were enrolled in this study. Genomic DNA samples of patients and healthy controls were genotyped using polymerase chain reaction with sequence-specific primers. The results obtained indicate that the minor allele of rs6330 (P corr = 2.4E-10) and rs2072446 (P corr = 0.02) are significantly overrepresented in stroke group, while the minor allele of rs734194 (P corr = 8.5E-10) was underrepresented in diseased subjects. Single nucleotide polymorphisms in NGF gene (rs6330) and NGFR gene (rs2072446 and rs734194) are associated with the disease. Furthermore, it was shown that the carriage of the NGF rs6330*T minor allele is associated with increased infarct volume and higher risk of recurrent stroke. In conclusion, our findings suggest that the NGF rs6330*T and NGFR rs2072446*T minor alleles might be nominated as a risk factor for developing ischemic stroke and NGFR rs734194*G minor allele as a protective against this disease at least in Armenian population.

The relevance of the study is caused by the necessity to form a plan for the development of secondary vocational education that provides training of the most popular and promising specialties and working professions in accordance with international standards and advanced technologies on the basis of the leading professional educational organizations. The goal of this article is to identify the main motives and meanings of applicants' choices of popular and prospective specialties of secondary vocational education and working professions during the psychological, pedagogical and sociological research to paint a sociological portrait of students of vocational education and specialties from the TOP-50 list. The goals of the research are to carry out a comparative analysis of: 1) professional self-determination, 2) value orientations, 3) attitudes toward the teaching and upbringing, 4) life plans of applicants and students. The leading method in investigating this problem is the method of questioning. In our study we surveyed the applicants and students of specialties from the TOP-50 list. Results of the research: In order to study certain aspects of the sociological portrait of students through the method of questioning of students from the TOP-50 specialties we compiled a sociological questionnaire that included four blocks. The questionnaire for students included 28 questions and the questionnaire for applicants included 33 open and closed questions with the use of different scales with the possibility of selecting several of the listed options and the fields for answers. The results of the questioning of applicants and students are presented; the similarities and differences of the key motives, life plans, values of applicants and students who have chosen perspective professions of secondary vocational education are identified and summarized.

This article describes the enzyme-catalyzed "green" synthesis of an unnatural poly(amino acid). dl-Tyrosine was polymerized under environmentally friendly conditions using linear-dendritic laccase complexes as initiators and water as solvent. The influence of the dendron generation in the linear-dendritic copolymers, the monomer concentration, and time and temperature on the polymer yields and molecular masses was investigated. Depending on the reaction conditions poly(tyrosine) with molecular mass (Mw) up to 82 kDa could be obtained in yields ranging between 45 and 69%. It was found that the linear-dendritic laccase complexes can induce further chain growth upon addition of fresh monomer to the preformed poly(tyrosine) in a fashion resembling the classic "living" polymerization. The structure of the poly(tyrosine) was investigated by NMR, FT-IR, and MALDI-TOF and it was discovered that the polymer chains consist of phenol repeating units linked together by C-C and C-O bonds randomly distributed along the backbone of the polymers. The materials formed are completely water-soluble and behave as typical poly(zwitterions) changing charge and size with the medium pH. DLS measurements reveal that the zeta potential of the polymers can vary between +15 mV at pH 1.2 with hydrodynamic diameter (Dh) = 6.7 nm to -35 mV at pH 11.8 and Dh = 10 nm. The isoelectric point was found at pH = 2.3-2.6, where Dh of the polymer is at the minimum (2.4 nm).

Enzymatic complexes, constructed by linear-dendritic copolymers and laccase, are used for the unprecedented one-pot biotransformation of fullerene (C60) into epoxide- and hydroxyl-derivatives under mild and environmentally friendly reaction conditions (45 °C and aqueous medium). The reaction is catalyzed by mediator pairs - N-hydroxy-5-norbornene-2,3-dicarboxylic acid imide/1-Hydroxybenzotriazole or 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)/1-Hydroxybenzotriazole used in equimolar amounts. After 24 and 48 h, the biotransformation products C60On, C60(OH)n, C60(H)n(OH)n, and/or C60On(H)m(OH)m range between 50 and 78%, respectively. Their structure is revealed by FTIR, NMR, and mass-spectrometry. The mechanism of the process is discussed and elucidated. The reaction procedure allows the repeated usage of the enzyme/linear-dendritic complex, which retains its catalytic activity after several cycles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

The first synthesis of asymmetric dendritic-linear-dendritic ABC block copolymers, that contain a linear B block and dissimilar A and C dendritic fragments is reported. Third generation poly(benzyl ether) monodendrons having benzyl alcohol moiety at their ''focal'' point were activated by quantitative titration with organome- tallic anions and the resulting alkoxides were used as initiators in the ''living'' ring- opening polymerization of ethylene oxide. The reaction proceeded in controlled fash- ion at 40-50 8C affording linear-dendritic AB block copolymers with predictable molecular weights (Mw ¼ 6000-13,000) and narrow molecular weight distributions (Mw/Mn ¼ 1.02-1.04). The propagation process was monitored by size-exclusion chro- matography with multiple detection. The resulting ''living'' copolymers were termi- nated by reaction either with HCl/tetrahydrofuran or with a reactive monodendron that differed from the initiating dendron not only in size, but also in chemical compo- sition. The asymmetric triblock copolymers follow a peculiar structure-induced self- assembly pattern in block-selective solvents as evidenced by size-exclusion chroma- tography in combination with multi-angle light scattering. V

This study describes the first Diels-Alder (DA) reaction performed in aqueous medium with highly hydrophobic compounds-fullerene (C 60) as the dienophile and anthracene (An) or tetracene (Tet) as the dienes, respectively. The reactions are performed in nanocontainers, constructed by self-assembly of linear-dendritic amphiphilic copolymers with poly(ethylene glycol), PEG or poly(ethylene oxide), PEO as the hydrophilic blocks and poly(benzyl ether) monodendrons as the hydrophobic fragments: G3PEO13k, dG3 and dG2. Comparative studies under identical conditions are carried out with an amphiphilic linear-linear copolymer, poly(styrene)1800- block-PEO2100, PSt-PEO, and the nonionic surfactant Igepal CO-720, IP720. The binding affinity of supermolecules built of these amphiphiles toward the DA reagents decreases in the following order: G3PEO13kdG3PSt-PEOdG2IP720. The kinetic constant of binding is evaluated for tetracene and decreases in a similar fashion: 5 x 10 (-7) M/min (G3PEO13k), through 4 x 10 (-7) M/min (PSt-PEO) down to 1.5 x 10 (-7) M/min for IP720. The mobility of substrates encapsulated in the micellar core, estimated by pyrene fluorescence decay, is 95-121 ns for the micelles of the linear-dendritic copolymers and notably higher for PSt-PEO (152 ns), revealing the much denser interior of the linear analogue. The apparent kinetic constant for the DA reaction of C 60 and Tet within the G3PEO13k supermolecule in aqueous medium is markedly higher than in organic solvent (toluene), 208 vs 1.82 M /min. With G3PEO13k the conversions reach 49% for the DA reaction between C 60 and An, and 55% for C 60 and Tet. Besides the monoadduct (26.5% yield) the reaction with An produces exclusively increasing amounts of D 2 h -symmetric antipodal bis-adduct, whose yield reaches up to 22.5% after 48 h. In addition to the environmentally friendly conditions notable advantages of the synthetic strategy described are the extended stability of the linear-dendritic nanovessels, the easy collection of the products formed, and the recovery and reuse of unreacted reagents and linear-dendritic copolymers.

We describe the construction of enzymatic nanoreactors through noncovalent envelopment of a glycoprotein by amphiphilic linear-dendritic AB or ABA copolymers. The synthetic procedure is based on the regioselective adsorption of dendritic poly(benzyl ether)-block-linear poly(ethylene glycol)-block-dendritic poly(benzyl ether) or linear poly(ethylene oxide)-block-dendritic poly(benzyl ether) copolymers onto the oxidative enzyme laccase from Trametes versicolor in aqueous medium. The complexes formed have improved catalytic activity compared with the native enzyme (77-85 nkat/mL vs 60 nkat/mL, respectively) and are more stable at elevated temperatures up to 70 degrees C. Experiments with deglycosylated laccase confirm that the glycoside fragments in the native enzyme serve as the anchor sites for the linear-dendritic copolymers. The enzymatic nanoreactors are able to effectively oxidize series of substrates: phenolic compounds (syringaldazine) and hydrophobic polyaromatic hydrocarbons (anthracene and benzo[a]pyrene) under "green" chemistry conditions.