Antimicrobial cationic polymers mainly contain two functional components: the cationic groups and the hydrophobic groups. The antimicrobial activity is influenced by the type, amount, location and distribution of these two components. This review summarizes the designs and syntheses of antimicrobial cationic polymers by controlling the above two factors. It involves the structural designs from primary to secondary structures, from covalent to noncovalent syntheses and from bulk to surface. Furthermore, it will discuss how to advance structural designs toward functional controls for optimizing the antimicrobial performances and biocompatibility of antimicrobial cationic polymers. It is anticipated that this review will provide some guidelines for developing molecular engineering of antimicrobial cationic polymers with tailor-made structures and functions.

The growth, photosynthesis, and respiration of the marine diatom Phaeodactylum tricornutum were examined under photoautotrophic and mixotrophic conditions. 100 mM glycerol, acetate, and glucose significantly increased specific growth rate, and mixotrophic growth achieved higher biomass concentrations. Under mixotrophic conditions, respiration rate (R d ) and light compensation irradiance (I c ) were significantly higher, but net maximum photosynthetic O 2 evolution rate (P m ) and saturation irradiance (I k ) were depressed. Organic carbon sources decreased the cell photosynthetic pigment content and chlorophyll a to c ratio, but with a higher carotenoid to chlorophyll a ratio. Ratios of variable to maximum chlorophyll fluorescence (F v /F m ) and 77 K fluorescence spectra of mixotrophic cells indicated a reduced photochemical efficiency of photosystem II. The results were accompanied by lower electron transport rate. Therefore, organic carbon sources reduced the photosynthesis efficiency, and the enhancement of biomass of P. tricornutum implied that organic carbon sources had more pronounced effects on respiration than on photosynthesis.

No abstract

As low as 1% content of a supramolecular catalyst, cucurbit[8]uril, is sufficient to accomplish the photodimerization of Brooker’s merocyanine within 10 minutes.

The population genetic structure of the crimson snapper Lutjanus erythropterus in East Asia was examined with a 427-bp hypervariable portion of the mtDNA control region. A total of 262 samples were collected and 75 haplotypes were obtained. Neutrality tests (Tajima's and Fu's) suggested that Lutjanus erythropterus in East Asia had experienced a bottleneck followed by population expansion since the late Pleistocene. Despite the low phylogeographic structures in mtDNA haplotypes, a hierarchical examination of populations in 11 localities from four geographical regions using analysis of molecular variance (AMOVA) indicated significant genetic differentiation among regions (ΦCT = 0.08564, p < 0.01). Limited gene flow between the eastern region (including a locality in the western Pacific Ocean and two localities in the East Sea) and three geographic regions of the South China Sea largely contributed to the genetic subdivision. However, comparisons among three geographic regions of the South China Sea showed little to no genetic difference. Populations of Lutjanus erythropterus in East Asia are inferred to be divided into two major groups: an eastern group, including populations of the western Pacific Ocean and the East Sea, and a South China Sea group, consisting of populations from northern Malaysia to South China. The results suggest that fishery management should reflect the genetic differentiation and diversity in East Asia.

wileyonlinelibrary.comVarious building blocks can be used to fabricate supra-amphiphiles, ranging from small molecules to polymers, from synthetic compounds to natural chemicals. [31][32][33][34][35][36] The preparation method is adapted to the solubility of these building blocks. The simplest method is to mix all the building blocks together in water or other solvent simultaneously. According to the fast dynamics of the noncovalent interactions, the supra-amphiphiles can spontaneously form and self-assemble in a short time. When some of the building blocks are not readily soluble in water, a good solvent for all building blocks is usually applied. For example, as shown in Figure 1, we mixed a nitrobenzene derivative (DNB) and a pyrene derivative (PYR) in tetrahydrofuran (THF), which is a good solvent for DNB and PYR. [37] The supra-amphiphile could form on the basis of the charge-transfer interaction. The PYR, which was a conventional amphiphile, self-assembled in water to form tubular structures, while the supra-amphiphiles could self-assemble in water to form vesicles. Therefore, the formation of supra-amphiphiles can be regarded as the first-level self-assembly based on the noncovalent synthesis of covalent components, and then the supra-amphiphiles can undergo second-level self-assembly to form well-defined organizations.Abundant studies have been reported on the design, fabrication and application of supra-amphiphiles. In this feature article, we would like to introduce recent progresses of supra-amphiphiles from molecular architecture to functional assemblies. Limited by the volume of this article and our knowledge, it is impossible to cover every aspect of this developing area, therefore, we will put special emphasis on a few topics where supra-amphiphiles function as surfactants, and in the areas of nanocarriers, photodynamic therapies, chemical analysis and functional interfaces. Hopefully, it can reflect in a way that the study on supra-amphiphiles is enriching the molecular engineering of supramolecular systems by combining the molecular architecture and functional assembly. Supra-Amphiphiles as SurfactantsSurfactants, referring to surface-active reagents which can induce significant decrease in interfacial tension by adsorption, are crucial substances for colloidal research, industrial applications as well as our daily life. Supra-amphiphiles can also be utilized as surfactants, functioning in emulsification, foaming, etc. As there is more flexibility in the structure of supra-amphiphiles compared to that of the covalent counterparts, finer tuning of interfacial tension and other physicochemical properties can be realized. In addition, the feature of noncovalent Supra-amphiphiles refer to amphiphiles which are fabricated on the basis of various noncovalent interactions and dynamic covalent bonds, including host-guest interaction, charge-transfer interaction, electrostatic interaction, imine bonds, etc. In this feature article, recent progresses of supra-amphiphiles from molecular architecture to func...

No abstract

RNA profiling reveals key contributors to affinity and selectivity in amiloride : RNA interactions, including a predictive model for ESSV recognition.