Aposporic development of gametophyte in Sematophyllum subpinnatum (Brid.) E. Britton (Sematophyllaceae) from capsule wall

In the present study, an axenic culture of Sematophyllum subpinnatum (Brid.) E. Britton was attempted from spores. However, spores failed to germinate, but protonemata were seen arising from the diploid capsule wall cells by apospory. Few cells of the capsule wall turned green, and the protoplast divided, resulting in the extension of the protoplast as a germ tube, which developed into protonemata. Protonemata were less spreading, and adult gametophytes developed from these protonemata. The aposporic plants so developed were transferred to soil, and they showed normal growth but with decreased branching. No sex organs and sporophytes were seen. This is the first report of aposporic development of S. subpinnatum from the capsule wall.

Determination of the Influence of Mechanical Properties of Capsules and Seeds on the Susceptibility to Feeding of Mononychus pubctumalbum in Endangered Plant Species Iris aphylla L. and Iris sibirica L.

The aim of the study was to determine the correlation between the mechanical resistance of iris seed capsules and seeds to Mononychus punctumalbum foraging. The principal component analysis (PCA) demonstrated that the first main component referred to the variety type in 68%, and the second main component described the stage of the ontogenetic development of the plant in 26%. As indicated by the values of each parameter measured, all the parameters were found to exert a strong impact on the variability of the analyzed system. The occurrence of weevil infestation was also strongly but negatively correlated with seed wall thickness and capsule wall thickness. There was a correlation of seed max load and seed mass with the occurrence of the weevil. The analysis of the mechanical resistance of iris seed capsules (in June 9.28 N and September 6.27 N for I. sibirica and in June 6.59 N and September 2.94 N for I. aphylla) and seeds (in June 15.97 N and September 344.90 N for I. sibirica and in June 16.60 N and September 174.46 N for I. aphylla) showed significant differences between the terms and species. The PCA analysis revealed that the first variable was correlated with the occurrence of weevil foraging.

A microfluidic methodology to identify the mechanical properties of capsules: comparison with a microrheometric approach

We present a microfluidic method to measure the elastic properties of a population of microcapsules (liquid drops enclosed by a thin hyperelastic membrane). The method is based on the observation of flowing capsules in a cylindrical capillary tube and an automatic inverse analysis of the deformed profiles. The latter requires results from a full numerical model of the fluid–structure interaction accounting for nonlinear membrane elastic properties. For ease of use, we provide them under the form of databases, when the initially spherical capsule has a membrane governed by a neo-Hookean or a general Hooke's law with different surface Poisson ratios. Ultimately, the microfluidic method yields information on the type of elastic constitutive law that governs the capsule wall material together with the value of the elastic parameters. The method is applied to a population of ovalbumin microcapsules and is validated by means of independent experiments of the same capsules subjected to a different flow in a microrheological device. This is of great interest for quality control purposes, as small samples of capsule suspensions can be diverted to a measuring test section and mechanically tested with a 10 % precision using an automated process.

Photochemistry of 2-Oxoacetates: from Mechanistic Insights to Profragrances and Bursting Capsules

Photoirradiation of 2-oxoacetates (α-ketoesters) with UV-A light proceeds via an intramolecular hydrogen abstraction of the triplet state in a Norrish type II pathway to form carbonyl compounds, carbon monoxide and/or dioxide, and a series of other side products. This review gives a detailed overview of the mechanistic aspects of photooxidation by explaining the pathways that yield the major products formed in the presence or absence of oxygen. Furthermore, it demonstrates how the photoreaction can be used for the light-induced controlled release of fragrances from non-polymeric profragrances, polymer conjugates and core-shell microcapsules in applications of functional perfumery. In the case of microcapsules, the gas formation accompanying the Norrish type II fragmentation can generate an overpressure that expands or cleaves the capsule wall to release fragrances and thus provides access to multi-stimuli responsive delivery systems.

A Subantarctic rare gastropod reveals a new type of spawn among heterobranchs

Spawn and specimens of Toledonia biplicata comb. nov. were collected from Burdwood Bank during March 2013. Species-level identification was derived from radular, shell and spawn characters. A low number of eggs laid per spawn (one to three), absence of an external gelatinous mass and a considerably thickened capsule wall (~50 µm) constitute a unique combination of spawn characters among heterobranchs. Egg capsules are ovoid in shape and measure 600–763 × 450–656 µm. They are filled with albuminous liquid, allowing complete intracapsular development of a single embryo. The developmental stages recognized are uncleaved eggs (153 µm in average diameter), veliger stages (279–378 µm in maximal length) and prehatchling juveniles (442–609 µm). Toledonia biplicata increases its volume 40-fold during its intracapsular development, whereas other comparable cephalaspids increase ≤ 4-fold. The role of the capsule wall as protection and an additional source of food is discussed. The adaptive value of these characters in relationship to the environmental conditions of the Magellanic region is discussed. A comparison with the spawn of other cephalaspids, nudibranchs and pleurobranchids is conducted, and the taxonomic implications are discussed. This is the first description of the spawn and developmental stages of a representative of the genus Toledonia.

A new species of Fossombronia (Marchantiophyta, Fossombroniineae,Fossombroniaceae) from high elevation mires in Latin America

Several populations of a partially submerged, robust, morphologically distinct Fossombronia were personally collected in central Mexico and several high elevation subpáramo communities in Venezuela. Comparative morphological studies of these populations with the type collections of F. peruviana, F. herzogii, F. ptychophylla, and F. australis, and a phylogenetic analysis of three chloroplast loci in 18 morphologically defined species of the genus were conducted to determine the taxonomic status of these populations. Both studies support the recognition of these populations as a new species of Fossombronia, which is named and described herein as Fossombronia delgadilloana. This new species resolves in a clade that is sister to F. peruviana, and is characterized by horizontal, planate, sub-longitudinally inserted leaves, widely dispersed antheridia, with basally expanded stalks, stipitate caulocalyces that lack lamellae, obovoid to ellipsoidal capsules, I-type inner capsule wall thickenings, and spores that are > 40µm, with reticulate distal wall ornamentation. Fossombronia herzogii is recognized as a new synonym of F. peruviana, and a new lectotype is designated for F. ptychophylla.

Chemical tailoring of one-dimensional polypyrene nanocapsules at a molecular level: towards ideal sulfur hosts for high-performance Li–S batteries

A novel 1D porous carbon nanocapsule (PCNC) has been successfully fabricated by heat treatment of the in situ synthesized polypyrene nanocapsule, where the diameter of the capsule wall can be easily tuned.

Utricularia sunilii (Lentibulariaceae), a striking new species from southern Western Ghats, Kerala, India

Utricularia sunilii, a new species of Utricularia Sect. Oligocista from Kerala state of Western Ghats is described here. The new species shows similarities with U. graminifolia in having 3-nerved foliar organs and thickened capsule wall along the margin of dehiscence but differs by deeply 3-lobed lower lip of corolla.