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Ring opening metathesis polymerization derived poly(norbornene) films and aggregates were crosslinked via photo chemically induced thiol-ene chemistry using a multifunctional thiol and the double bonds present in the polymer backbones. The presented method was illustrated by the description of a negative-toned photoresist formulation based on above mentioned ingredients.

The pantropical orchid genus Polystachya comprises approximately 230 species and shows variation in ploidy. For ongoing phylogenetic investigations in this genus, a knowledge of ploidy is necessary. We also looked for a correlation between genome size and guard cell length, so that we could estimate ploidy from preserved material and plants containing high levels of mucilage that are difficult to analyse by flow cytometry (FC). For estimates of ploidy, we measured genome size using FC. For investigations of guard cell lengths and densities, tangential cuts and nail varnish impressions were made. Diploid, tetraploid and hexaploid individuals with genome sizes ranging from 0.58 to 1.80 pg (1C-values) were found. Guard cell length ranged from 15 to 39 µm. The minimum guard cell length was greater in polyploids, but diploid species had a large range of guard cell lengths that encompassed the size range found in polyploids. Although previous studies have found that guard cell length can be used to estimate ploidy in cases in which the genome size range is large, this is not applicable to genera with a small genome size, such as Polystachya. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163, 223–233.

Here evidence for reticulation in the pantropical orchid genus Polystachya is presented, using gene trees from five nuclear and plastid DNA data sets, first among only diploid samples (homoploid hybridization) and then with the inclusion of cloned tetraploid sequences (allopolyploids). Two groups of tetraploids are compared with respect to their origins and phylogenetic relationships.Sequences from plastid regions, three low-copy nuclear genes and ITS nuclear ribosomal DNA were analysed for 56 diploid and 17 tetraploid accessions using maximum parsimony and Bayesian inference. Reticulation was inferred from incongruence between gene trees using supernetwork and consensus network analyses and from cloning and sequencing duplicated loci in tetraploids.Diploid trees from individual loci showed considerable incongruity but little reticulation signal when support from more than one gene tree was required to infer reticulation. This was coupled with generally low support in the individual gene trees. Sequencing the duplicated gene copies in tetraploids showed clearer evidence of hybrid evolution, including multiple origins of one group of tetraploids included in the study.A combination of cloning duplicate gene copies in allotetraploids and consensus network comparison of gene trees allowed a phylogenetic framework for reticulation in Polystachya to be built. There was little evidence for homoploid hybridization, but our knowledge of the origins and relationships of three groups of allotetraploids are greatly improved by this study. One group showed evidence of multiple long-distance dispersals to achieve a pantropical distribution; another showed no evidence of multiple origins or long-distance dispersal but had greater morphological variation, consistent with hybridization between more distantly related parents.

The pantropical orchid genus Polystachya is the subject of ongoing taxonomic work. We inferred phylogenetic relation¬ships in the genus using 5.3 kb of plastid DNA, for 83 out of ca. 240 species and 12 out of 15 sections, as well as five outgroup species. We also collected ploidy data using chromosome counts and genome size estimates. Bayesian and parsimony trees were congruent with each other and well resolved. Polystachya appears monophyletic based on current sampling, provided that the name P. neobenthamia is used instead of Neobenthamia gracilis for that species. The current sectional classification does not define monophyletic groups, but the present study can be used as the basis for a future sectional classification. Areas postulated as Pleistocene refugia for wet tropical forests in Africa also form centres of diversity for the genus. Biogeographical analyses using DIVA and Lagrange show an early radiation in eastern Africa, followed by separate radiations in eastern and western Africa. Subsequent dispersal from western to eastern Africa has occurred at a much higher rate than from east to west. Dispersal to the Neotropics occurred more than once, and one lineage has spread recently and rapidly throughout the tropics. Polyploidy has occurred several times during the diversification of the genus, most notably in association with the recent pantropical dispersal.

Presently, commercially available lithium-ion batteries use graphite based anodes in combination with organic carbonate (e.g. Propylene Carbonate, PC, Ethylene Carbonate, EC) electrolytes. In this kind of Li-ion batteries the solid electrolyte intephase (SEI) formation process on the surface of graphite is crucial since it strongly influence the performances of the batteries systems [1]. It is known that the use of electrolyte additives (e.g. containing vinylene groups) improves the design of the resulting SEI on the graphite and leads to more efficient cycling of the material [2]. For that, several types of additives have been already studied and tested and intense research is now focused on the optimization of their design for a more effective film-forming efficiency. Ionic Liquids (ILs), room temperature molten salts typically showing a very low vapor pressure, high thermal stability, wide electrochemical windows and good conductivity at room and sub-room temperatures [3-4]. These properties make them very attractive candidates for the use as electrolytes in electrochemical devices such as batteries, particularly to increase the safety and the operative temperature range. So far, different types of ILs have been already used in combination with graphite electrodes with promising results [5-7]. However, only few reports studied the SEI formation process on graphite electrodes when ILs are used in the electrolytes as well as the contribution of additives to the SEI formation in such electrlytes [8]. Recently, we investigated the role of the additive Vinylene Carbonate (VC) in ILs-based electrolyte. The results of our studies indicated that when ultrapure ILs are used as electrolytes in combination with graphite electrodes, the need of additives in the electrolyte solution is strictly related to the film-forming ability of the ILs [9] themselves. For instance, in electrolyte solution based on the ultrapure ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethansulfonyl)imide (PYR14TFSI) the use of VC appears to be indispensable because such IL does not display film-forming ability. To the contrary, in electrolyte solution based on the ultrapure N-methyl-Npropylpyrrolidinium bis(fluorosulfonyl)imide (PYR13FSI) the presence of VC was not strictly required because this IL displays film-forming ability. In order to investigate the film-forming ability of PYR13FSI and the possibility of using this IL as additive or co-solvent in pure IL-based solutions, we prepare different mixture of PYR13FSI -PYR14TFSI with and without VC. These solutions have been used in combination with the graphite electrode and their influence on the specific capacity, the cycling efficiency and the cycling stability of the electrodes have been investigated. As example, Fig. 1 shows the cyclic voltammetry at 50 μV sec of graphite electrode in 0.3 M LiTFSI + PYR14TFSI + 5%wt. VC (A); 0.3 M LiTFSI + PYR14TFSI [50%] PYR13FSI [50%] + 5%wt. VC (B) and 0.3 M LiTFSI + PYR13FSI + 5%wt. VC (C). Also the influence of two different Lithium salt (Lithium bis(trifluoromethansulfonyl)imide, LiTFSI and Lithium exafluophosphate, LiPF6) on the performance of graphite electrode in the mixtures of PYR13FSI PYR14TFSI has been investigated. These studies clearly evidence that the Li-salt strongly influence the performance of graphite electrode in combination with ILs-based solutions.

The possibility to electrodeposit silicon directly on a copper current collector out of organic electrolyte and ionic liquid was investigated with the aim to alloy the deposited silicon with lithium to prove the possible use as negative electrode in lithium ion batteries. Cyclovoltammetric analyses have shown in comparison to electrodes containing high crystalline silicon similar behaviour during the electrochemical alloying and dealloying process. SEM analyses have shown a particle size of the deposited silicon in submicron range.

Polymer/ionic liquid composites were investigated as solvent-free electrolytes for lithium batteries. Ternary electrolytes based upon poly(ethylene oxide), an ionic liquid and a conducting salt were UV crosslinked with benzophenone as the photoinitiator. Crosslinking leads to an increase in mechanical stability of the PEO composites. This straight-forward process provides a way to increase the content of ionic liquid and thus to raise ionic conductivity without loss of mechanical stability. Impedance measurements showed that the ionic conductivity of the composites is not affected by the UV curing process. Moreover, the UV curing process causes a decrease in the degree of crystallinity in the PEO composites which contributes to an increase in ionic conductivity. The present work is related to safety issues of lithium batteries.

We synthesized two carminic acid (7-alpha-d-glucopyranosyl-9,10-dihydro-3,5,6,8-tetrahydroxy-1-methyl-9,10-dioxo-2-anthracene carboxlic acid, CA)-GnRH conjugates to be used as a model for potential photoactive targeted compounds. CA was conjugated to the epsilon-amino group of [d-Lys(6)]GnRH through its carboxylic moiety or via a beta-alanine spacer (beta-ala). Redox potentials of CA and its conjugates were determined. We used electron spin resonance (ESR) and spin trapping techniques to study the light-stimulated redox properties of CA and its CA-GnRH conjugates. Upon irradiation, the compounds stimulated the formation of reactive oxygen species (ROS), that is, singlet oxygen ((1)O(2)) and oxygen radicals (O(2)(-*) and OH(*)). Both conjugates exhibited higher ROS production than the non-conjugated CA. The bioactivity properties of the CA conjugates and the parent peptide, [d-Lys(6)]GnRH, were tested on primary rat pituitary cells. We found that the conjugates preserved the bioactivity of GnRH as illustrated by their capability to induce ERK phosphorylation and LH release.

The solid electrolyte interphase (SEI) formation on commercial graphite, KS6 TIMCAL, in two different ionic liquids, N-methyl-N-butyl pyrrolidinium bis(trifluoromethansulfonyl)imide (PYR14TFSI) and N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)imide (PYR13FSI) has been investigated. The role of the Vinylene Carbonate (VC) addition to the ionic liquid-based electrolyte has also been studied. To monitor the change at the electrode/electrolyte (IL) interface during the SEI formation, we took advantage of the in situ Fourier transform infrared spectroscopy (FTIRS). The results of the investigation performed at room temperature are presented in this manuscript.

Rat bone morphogenetic protein-4 (rBMP-4) cDNA was cloned from rat osteoblasts by RT-PCR and expressed in E. coli. Monomeric, dimeric and polymeric forms of recombinant rat BMP-4 (rrBMP-4) were obtained from inclusion bodies after solubilization with urea. The dimer was separated from the remaining polymer and host cell contaminants using size exclusion chromatography. Furthermore, purified rrBMP-4 was stabilized at low urea concentration (40 mM) and at pH 8.5 through the addition of bovine serum albumin. Both, rrBMP-4 dimer and polymer were biologically active as tested by the induction of alkaline phosphatase activity in MC3T3-E1 cells.

Ring opening metathesis polymerization derived poly(norbornene) films and aggregates were crosslinked via photo chemically induced thiol-ene chemistry using a multifunctional thiol and the double bonds present in the polymer backbones. The presented method was illustrated by the description of a negative-toned photoresist formulation based on above mentioned ingredients.

The thiol-ene reaction is a established photoreaction of multifunctional thiols and enes. Virtually any type of ene will participate in a free radical polymerisation process with a thiol. An advantage over many other photochemical reactions is that the reaction proceeds almost as rapidly in ambient conditions as in inert atmosphere. In this work we introduce the UV-crosslinking of polynorbornenes made by ring opening metathesis polymerization making use of the residual double bond in the polymer backbone. The crosslinking experiments were done in thin films and were followed by FTIR measurements, to proof the accessibility of double-bonds in the polymers for the addition of the thiols. As a result of these pre-experiments we created flexible and light transmitting films. To further increase the scope of this reaction, amphiphilic block copolymers were prepared and used to form block copolymer micelles in a selective solvent, which were subsequently crosslinked with pentaerythritol tetra(3-mercaptopropionate) (PETMP). FT-IR, DLS and SEM-measurements were used to prove the successful crosslinking and thus nanoparticle formation.

Foot size proportionate to stature is smaller in women than in men, and small feet apparently contribute to perceived physical attractiveness of females. This exploratory study investigated the sex difference in relative foot length and inter-relations among foot length, physique, and foot preference ratings in samples from Austria and Canada, each comprised of 75 men and 75 women. The findings included the following lines of evidence: the sex difference in relative foot length replicated in both data sets; the magnitude of this sex effect was large. Relative foot length was smaller in young, nulliparous, and slim women. Pointed-toe and high-heel shoes were more likely worn by smaller, lighter, and slimmer women. Men reported liking women's feet in general more than vice versa. A vast majority of both men and women favored small feet in women, but large feet in men. One's own foot size appeared to correspond to evaluations of attractiveness; particularly, women with small feet preferred small feet in women in general. The preference for small feet in women was convergent across different methods of evaluating attractiveness. Directions for investigations in this emerging field of research on physical attractiveness are discussed.

Films of the biopolyester poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate) PHB-HV, a microbe-derived poly(hydroxyalkanoate), were crosslinked with 2,6-bis(4-azidobenzylidene)-4-methylcyclohexanone BA under UV irradiation. The degree of network formation reached 90% within irradiation times lower than 1 min. The 3 wt% concentration of BA in PHB-HV was found to be the optimum with respect to the rate of crosslinking relative to the rate of chain scission, which were derived from Charlesby-Pinner analyses. The PHB-HV/BA system could successfully be used for the generation of one- and two-step photolithographic imprints with reasonable resolution in the 50 μm range and, hence, proved to be an efficient system for finishing with biopolyesters.

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