A review on the applications of Traditional Chinese medicine polysaccharides in drug delivery systems

Traditional Chinese medicine polysaccharides (TCMPs) are plentiful and renewable resources with properties such as biocompatibility, hydrophilicity, biodegradability, and low cytotoxicity. Because the polysaccharide molecular chain contains a variety of active groups, different polysaccharide derivatives can be easily produced through chemical modification. They have been increasingly used in drug delivery systems (DDS). However, the potential of polysaccharides is usually ignored due to their structural complexity, poor stability or ambiguity of mechanisms of actions. This review summarized the applications of TCMPs in DDS around four main aspects. The general characteristics of TCMPs as drug delivery carriers, as well as the relationships between structure and function of them were summarized. Meanwhile, the direction of preparing multifunctional drug delivery materials with synergistic effect by using TCMPs was discussed. This review aims to become a reference for further research of TCMPs and their derivatives, especially applications of them as carriers in pharmaceutical preparation industry.

Bulk and spatially resolved extracellular metabolomics of free-living nitrogen fixation

Soil microorganisms drive ecosystem function, but challenges of scale between microbe and ecosystem hinder our ability to accurately quantify and predictively model the soil microbe-ecosystem function relationship. Quantifying this relationship necessitates studies that systematically characterize multi-omics of soil microorganisms and their activity across sampling scales from spatially resolved to bulk measures, and structural complexity, from liquid pure culture to in situ. To address this need, we cultured two diazotrophic bacteria in liquid and solid media, with and without nitrogen (N) to quantify differences in extracellular metabolites associated with nitrogen fixation under increasing environmental structural complexity. We also quantified extracellular metabolites across sampling scales including bulk sampling via GC-MS analysis and spatially resolved analysis via MALDI mass spectrometry imaging. We found extracellular production of inorganic and organic N during free-living nitrogen fixation activity, highlighting a key mechanism of terrestrial N contributions from this process. Additionally, our results emphasize the need to consider the structural complexity of the environment and spatial scale when quantifying microbial activity. We found differences in metabolite profiles between culture conditions, supporting previous work indicating environmental structure influences microbial function, and across scales, underscoring the need to quantify microbial scale conditions to accurately interpret microbial function.

Intestinal commensal microbiota and cytokines regulate Fut2+ Paneth cells for gut defense

Paneth cells are intestinal epithelial cells that release antimicrobial peptides, such as α-defensin as part of host defense. Together with mesenchymal cells, Paneth cells provide niche factors for epithelial stem cell homeostasis. Here, we report two subtypes of murine Paneth cells, differentiated by their production and utilization of fucosyltransferase 2 (Fut2), which regulates α(1,2)fucosylation to create cohabitation niches for commensal bacteria and prevent invasion of the intestine by pathogenic bacteria. The majority of Fut2− Paneth cells were localized in the duodenum, whereas the majority of Fut2+ Paneth cells were in the ileum. Fut2+ Paneth cells showed higher granularity and structural complexity than did Fut2− Paneth cells, suggesting that Fut2+ Paneth cells are involved in host defense. Signaling by the commensal bacteria, together with interleukin 22 (IL-22), induced the development of Fut2+ Paneth cells. IL-22 was found to affect the α-defensin secretion system via modulation of Fut2 expression, and IL-17a was found to increase the production of α-defensin in the intestinal tract. Thus, these intestinal cytokines regulate the development and function of Fut2+ Paneth cells as part of gut defense.

Crystallographic complexity partition analysis

We present an illustrative analysis of the complexity of a crystal structure based on the application of Shannon’s entropy formula in the form of Krivovichev’s complexity measures and extended according to the contributions of distinct discrete probability distributions derived from the atomic numbers and the Wyckoff multiplicities and arities of the atoms and sites constituting the crystal structure, respectively. The results of a full crystallographic complexity partition analysis for the intermetallic phase Mo3Al2C, a compound of intermediate structural complexity, are presented, with all calculations performed in detail. In addition, a partial analysis is discussed for the crystal structures of α- and β-quartz.

Double-Gate Operation of Metal Nanodot-Array-Based Single-Electron Device

Multidot single-electron devices (SEDs) can realize new types of computing technologies, such as reconfigurable and reservoir computing. The self-assembled metal nanodot-array film attached with multiple gates is a candidate for use in such SEDs to achieve high functionality. However, the single-electron properties of such a film have not yet been investigated in use with optimally controlled multiple gates because of structural complexity having many nanodots. In this study, Fe nanodot-array-based double-gate SEDs were fabricated and their single-electron properties modulated by the top- and bottom-gate voltages (VT and VB, respectively) were investigated. As reported in our previous study, the drain current (ID) exhibited clear oscillations against VB (i.e., Coulomb blockade oscillation) in a part of the devices, originating from a single dot among several dots. The phase of the Coulomb blockade oscillation systematically shifted with VT, indicating that the charge state of the single dot was clearly controlled by both the gate voltages despite the multidot structure and the metal multidot SED has potential for logic-gate operation. The top and bottom gates affected the electronic state of the dot unevenly owing to the geometrical effect caused by the dot shape and size of the surrounding dots.

Vegetation attributes drive the taxonomic richness and functional composition of beetles and spiders in mountainous urban green spaces

Urban green spaces (UGS) enhance the quality of life in urban environments and serve as habitat corridors or refuge for organisms, including beetles and spiders. The attributes of UGS allow them to harbour species that offer essential ecosystem services. However, the ability of UGS to provide services is limited by the extent to which they have been altered anthropogenically. We described the taxonomic richness and functional composition of arthropods in a mountainous urban ecosystem of Ghana by focussing on the activity of both beetles and spiders at the family level. Two main land-use types (woodlands and built-up areas) were identified and characterised based on the presence or absence of certain vegetation attributes. Sixteen plots in each land-use type with sizes 20 × 20 m were demarcated and fitted with four pitfall traps in each plot to sample continuously for eight weeks, the activity density of both beetles and spiders. Samples were sorted into families and functional groups (detritivores, fungivores, herbivory and predators). The taxonomic richness and activity density were both significantly higher in the woodlands than in the built-up areas. Similarly, all functional groups showed a higher affinity to the woodlands than the built-up areas. Habitat attributes defined by plant diversity and structural complexity were the underlying drivers explaining the differences in arthropod communities between the land-use types. Though the built-up areas seem degraded and open, the remaining small vegetation patches still support the activities of some taxa that should merit the protection of such remnant vegetation in urban ecosystems.

Assessment of food security of the regions of the Arctic zone of the Russian Federation

Ensuring food security and promoting the development of agriculture are included in the priority goals of sustainable development of the Arctic zone of the Russian Federation until 2035. The structural complexity and multidimensionality of food security in the region requires a clear methodology for its assessment. The article presents the results of a study of food security in the regions of the Arctic zone of the Russian Federation. This study is based on an analysis of the advantages and disadvantages of existing methods for assessing food security in the regions of the Arctic zone of the Russian Federation. The authors proposed a methodology for assessing the food security of the regions of the Arctic zone of the Russian Federation, which makes it possible to translate a phased multivariate analysis (the methodology was tested on the example of the Chukotka Autonomous Region).

Numerical analysis of mechanical damage on concrete under high temperatures

Concrete is a widespread material all over the world. Due to this material’s heterogeneity and structural complexity, predicting the behavior of concrete structures under extreme environmental conditions is a very challenging task. High temperatures lead to microstructural changes which affect the macrostructural performance. In this context, computational tools that allow the simulation of structures may assist the analysis, by reproducing varied situations of thermal and mechanical loading and boundary conditions. In order to contribute to this scenario, this study proposes a numerical methodology to simulate the thermomechanical behavior of concrete under temperature gradients, through inverse analyses and a user subroutine implemented in Abaqus software. Thermal loading effects were considered as loading data for a damage model. Experimental data available in the literature was adopted for adjustment and validation purposes. The preliminary results presented herein encourage further improvements so as to allow realistic simulations of such an important aspect of concrete’s behavior.

Urbanization and plant pathogen infection interact to affect the outcome of ecological interactions in an experimental multitrophic system

Urbanization can change interactions in insect communities, and the few studies of tritrophic interactions in urban settings focus on interactions between plants, herbivorous insects and their mutualists and natural enemies. Plant pathogen infection is also widespread and common, and infection may also alter such interactions, but we have no understanding of whether the ecological consequences of pathogen infection vary with urbanization. Using replicated aphid colonies on experimental plants, we investigated how infection by the plant pathogen Botrytis cinerea influences interactions between plants, aphids and the aphid natural enemies and ant mutualists in highly urbanized, suburban and rural study sites. Aphid and natural enemy abundance were highest in the suburban site, while mutualist ants were most abundant in the urban site, reversing the usual positive density-dependent relationship between natural enemies and aphids. The effect of pathogen infection varied with trait and site, mediated by natural enemy preference for hosts or prey on uninfected plants. The effect of infection on aphid abundance was only seen in the suburban site, where natural enemies were most abundant on uninfected plants and aphid numbers were greatest on infected plants. In the urban site, there was no effect of infection, while in the rural site, aphid numbers were lower on infected plants. Uninfected plants were smaller than infected plants and differed between locations. This study suggests that the effects of urbanization on ecological interactions may become more complex and difficult to predict as we study ecological assemblages and communities at greater levels of structural complexity.

MatCalib: a Matlab software package for Bayesian modeling of radiocarbon ages subject to temporal order constraints

<abstract> <p>Radiocarbon ages must be calibrated due to the remarkable fluctuations of the atmospheric radiocarbon level. The traditional method (e.g., Calib) does not make use of any constraint such as the temporal/stratigraphical ordering of the ages, thereby resulting in one or several large age ranges. Bayesian age modeling is advantageous over the traditional method in several aspects. First, it can provide precise age estimates by applying some constraints known <italic>a priori</italic>. Second, it may provide a timing of an archaeological feature or a geological event that is unable to be dated directly. Although several Bayesian age modeling frameworks have been developed, inexperienced users may need not only a more user-friendly environment for data entry and definition of their project-specific problem, but also a powerful post-processing tool for analyzing and visualizing the results. Here a hierarchical Bayesian model with a minimum level of structural complexity is presented. It provides users with a flexible and powerful framework to incorporate radiocarbon ages into a sequence along a one-dimensional continuum so that it best reveals their temporal order, thereby yielding a more precise timing. The accompanying Matlab software package not only complements the existing MatCal package designed to calibrate radiocarbon ages individually, but also serves as an alternative to the online tools of Bayesian radiocarbon age modeling such as OxCal and BCal.</p> </abstract>