Functional Synchronization of Biological Rhythms in a Tritrophic System

In a tritrophic system formed by a plant, an herbivore and a natural enemy, each component has its own biological rhythm. However, the rhythm correlations among the three levels and the underlying mechanisms in any tritrophic system are largely unknown. Here, we report that the rhythms exhibited bidirectional correlations in a model tritrophic system involving a lima bean, a pea leafminer and a parasitoid. From the bottom-up perspective, the rhythm was initiated from herbivore feeding, which triggered the rhythms of volatile emissions; then the rhythmic pattern of parasitoid activities was affected, and these rhythms were synchronized by a light switch signal. Increased volatile concentration can enhance the intensity of parasitoid locomotion and oviposition only under light. From the top-down perspective, naive and oviposition-experienced parasitoids were able to utilize the different volatile rhythm information from the damaged plant to locate host leafminers respectively. Our results indicated that the three interacting organisms in this system can achieve rhythmic functional synchronization under a natural light-dark photoperiod, but not under constant light or darkness. These findings provide new insight into the rhythm synchronization of three key players that contribute to the utilization of light and chemical signals, and our results may be used as potential approaches for manipulating natural enemies

Predicting the components and types of kerogen in shale by combining machine learning with NMR spectra

This study aims to develop a new method that combines machine learning with nuclear magnetic resonance (NMR) spectra to predict the kemgen components and types. Kerogen is the primary hydrocarbon source of shale oil/gas, and nearly half of the hydrocarbons in shale are adsorbed in kemgen. The adsorption and hydrocarbon generation capacity of kerogen is directly related to its types, molecular components, and structures. Fruitful researches studying kerogen at the molecular level have been conducted. Unfortunately, these methods are complicated, time-consuming, and labor-intensive. Our method has the advantages of high-throughput prediction, high accuracy, and time savings compared with the existing methods. Additionally, this method simplifies the operations from repetitive trial and error. This study proposes a solution to convert non-uniform two-dimensional (2D) graph into a uniform one-dimensional (1D) matrix, which makes 2D graph data available for machine learning models. An automatic labeling platform is constructed that annotated over 22,000 groups of organic matter molecules and their NMR spectra. The results show that the carbon, hydrogen, and oxygen element prediction accuracy reach 96.1%, 94.8%, and 81.7%, respectively. In addition, the accuracy of the three kerogen types is approximately 90% in total. These results reflect the excellent performance of the machine learning method. Therefore, our work provides an automated and intelligent prediction and analysis method, which is a powerful and superior tool in kerogen studies at the molecular level

Gram-Scale Synthesis of Hydrophilic PEI-Coated AgInS₂ Quantum Dots and Its Application in Hydrogen Peroxide/Glucose Detection and Cell Imaging

Assisted with polyethylenimine, 4.0 L of water-soluble AgInS₂ quantum dots (AIS QDs) were successfully synthesized in an electric pressure cooker. As-prepared QDs exhibit yellow emission with a photoluminescence (PL) quantum yield up to 32%. The QDs also show excellent water/buffer stability. The highly luminescent AIS QDs are used to explore their dual-functional behavior: detection of hydrogen peroxide (H₂O₂)/glucose and cell imaging. The amino-functionalized AIS QDs show high sensitivity and specificity for H₂O₂ and glucose with detection limits of 0.42 and 0.90 μM, respectively. A linear correlation was established between PL intensity and concentration of H₂O₂ in the ranges of 0.5–10 μM and 10–300 μM, while the linear ranges were 1–10 μM and 10–1000 μM for detection of glucose. The AIS QDs reveal negligible cytotoxicity on HeLa cells. Furthermore, the luminescence of AIS QDs gives the function of optical imaging

Early development of Silvetia babingtonii (Fucales, Phaeophyceae)

Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on development and life cycle of this alga hinder the development of techniques for the sporeings and cultivation. In this study, internal structure of oogonium and antherium of S. babingtonii was observed with hematoxylin and eosin staining and through microscope. Meanwhile, early development from zygotes to juvenile sporelings was studied at 20 degrees C under 60-100 mu mol photons m(-2) s(-1). Zygotes germinated and divided into thallus and rhizoid cells. The larger thallus cells further divided and developed into juvenile sporelings; while the smaller rhizoid cells divided and elongated into rhizoid hairs. These findings documented the life cycle of S. babingtonii and provided fundamental knowledge for sporeling nursery in the near future

Scaling up the Aqueous Synthesis of Visible Light Emitting Multinary AgInS₂/ZnS Core/Shell Quantum Dots

Approximately 3 g of water-soluble AgInS₂/ZnS core/shell quantum dots (AIS/ZnS QDs) with a maximum photoluminescence quantum yield of up to 39.1% was synthesized in an aqueous solution of gelatin and thioglycolic acid (TGA). The composition of the AIS QDs could be readily adjusted by controlling the molar ratio of the starting Ag/In precursors in the reaction solution, which leads to a tunable emission ranging from 535 to 607 nm. The as-prepared core/shell QDs exhibit excellent photostability and water/buffer stability. More importantly, these cadmium-free hydrophilic AIS/ZnS core/shell QDs are biocompatible and can be directly utilized in cancer cell imaging

Tuning the Band Gap of Cu₂ZnSn(S,Se)₄ Thin Films via Lithium Alloying

Alkali metal doping plays a crucial role in fabricating high-performance Cu­(In,Ga)­(S,Se)₂ and Cu₂ZnSn­(S,Se)₄ (CZTSSe) thin film solar cells. In this study, we report the first experimental observation and characterizations of the alloyed Li_<i>x</i>Cu_2–<i>x</i>ZnSn­(S,Se)₄ thin films. It is found that Cu⁺ ions in Cu₂ZnSn­(S,Se)₄ thin films can be substituted with Li⁺ ions, forming homogeneous Li_<i>x</i>Cu_2–<i>x</i>ZnSn­(S,Se)₄ (0 ≤ <i>x</i> ≤ 0.29) alloyed thin films. Consequently, the band gap, conduction band minimum, and valence band maximum of Li_<i>x</i>Cu_2–<i>x</i>ZnSn­(S,Se)₄ thin films are profoundly affected by Li/Cu ratios. The band alignment at the Li_<i>x</i>Cu_2–<i>x</i>ZnSn­(S,Se)₄/CdS interface can be tuned by changing the Li/Cu ratio. We found that the photovoltaic parameters of the Li_<i>x</i>Cu_2–<i>x</i>ZnSn­(S,Se)₄ solar cell devices are strongly influenced by the Li/Cu ratios. Besides, the lattice constant, carrier concentration, and crystal growth of Li_<i>x</i>Cu_2–<i>x</i>ZnSn­(S,Se)₄ thin films were studied in detail

MicroRNA-133 inhibits behavioral aggregation by controlling dopamine synthesis in locusts.

Phenotypic plasticity is ubiquitous and primarily controlled by interactions between environmental and genetic factors. The migratory locust, a worldwide pest, exhibits pronounced phenotypic plasticity, which is a population density-dependent transition that occurs between the gregarious and solitary phases. Genes involved in dopamine synthesis have been shown to regulate the phase transition of locusts. However, the function of microRNAs in this process remains unknown. In this study, we report the participation of miR-133 in dopamine production and the behavioral transition by negatively regulating two critical genes, henna and pale, in the dopamine pathway. miR-133 participated in the post-transcriptional regulation of henna and pale by binding to their coding region and 3' untranslated region, respectively. miR-133 displayed cellular co-localization with henna/pale in the protocerebrum, and its expression in the protocerebrum was negatively correlated with henna and pale expression. Moreover, miR-133 agomir delivery suppressed henna and pale expression, which consequently decreased dopamine production, thus resulting in the behavioral shift of the locusts from the gregarious phase to the solitary phase. Increasing the dopamine content could rescue the solitary phenotype, which was induced by miR-133 agomir delivery. Conversely, miR-133 inhibition increased the expression of henna and pale, resulting in the gregarious-like behavior of solitary locusts; this gregarious phenotype could be rescued by RNA interference of henna and pale. This study shows the novel function and modulation pattern of a miRNA in phenotypic plasticity and provides insight into the underlying molecular mechanisms of the phase transition of locusts