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Metal-organic framework (MOF) glasses are a fascinating new class of materials, yet their prosperity has been impeded by the scarcity of known examples and limited vitrification methods. In the work described in this report, we applied synergistic stimuli of vapor hydration and thermal dehydration to introduce structural disorders in interpenetrated

To solve the problem of difficult hazelnut harvesting in mountainous areas of Liaoning, China, a small pneumatic hazelnut harvesting machine was designed, which can realize negative pressure when picking up hazelnut mixtures and positive pressure when cleaning impurities. The key structure and parameters of the harvesting machine were determined by constructing a mechanical model of the whole machine and combining theoretical analysis and operational requirements. To explore the harvesting machine scavenging performance, Liaoning hazelnut No. 3 with a moisture content of 7.47% was used as the experimental object. Firstly, the terminal velocity of hazelnuts and fallen leaves was measured using a material suspension velocity test bench. Secondly, the gas–solid two-phase flow theory was applied comprehensively, and the motion state, particle distribution, and air flow field distribution of hazelnuts from the inlet to the outlet of the pneumatic conveying device were simulated and analyzed using the coupling of computational flow fluid dynamics method (CFD) and discrete element method (DEM) to evaluate the cleaning performance from the perspective of the net fruit rate of hazelnuts in the cleaning box. Finally, a Box–Behnken design experiment was conducted with the sieve plate angle, the distance of the sieve plate, and the air flow velocity as factors and the net fruit rate of hazelnuts as indicators to explore the influence of the three factors on the net fruit rate of hazelnuts. The parameter optimization module of Design-Expert software was used to obtain the optimal combination of parameters for the factors. The experimental results show that the test factors affecting the test index are the following: the air flow rate, the angle of the screen plate, and the distance of the screen plate. The best combination of parameters was an air flow velocity of 14.1 m∙s−1, a sieve plate angle of 55.7°, and a distance of the sieve plate of 33.2 mm. The net fruit rate of hazelnuts was 95.12%. The clearing performance was stable and can guarantee the requirements of hazelnut harvester operation, which provides a certain theoretical basis for the design of a nut harvester.

The loss of characteristic nutrient glucoraphanin during the shelf life seriously affects the nutritional quality of broccoli. Here, we monitored the changes in the levels of sulfur donors (cysteine and glutathione) required for glucoraphanin biosynthesis. Similar to glucoraphanin, cysteine content decreased sharply. Continuous down-regulation of BoCysK1 and BoCysK2 genes encoding cysteine synthase might account for cysteine loss. Contrarily, glutathione content accumulated steadily, which might owe to the up-regulation of biosynthetic gene (BoEC1). Additionally, the change of malondialdehyde content was positively correlated with glutathione, implying that oxidative stress might stimulate glutathione accumulation. Nevertheless, the expression of BoGSTF11 gene encoding glutathione S-transferases was down-regulated, which blocked the supply of glutathione. The increase in the content of raphanusamic acid (degradation product) indicated that insufficient supply of sulfur donors not only could constrain the biosynthesis of glucoraphanin but also triggered its degradation.

Molecular recognition is an attractive approach to designing sensitive and selective sensors for volatile organic compounds (VOCs). Although organic macrocycles and cages have been well-developed for recognising organics by their adaptive pockets in liquids, porous solids for gas detection require a deliberate design balancing adaptability and robustness. Here we report a dynamic 3D covalent organic framework (dynaCOF) constructed from an environmentally sensitive fluorophore that can undergo concerted and adaptive structural transitions upon adsorption of gas and vapours. The COF is capable of rapid and reliable detection of various VOCs, even for non-polar hydrocarbon gas under humid conditions. The adaptive guest inclusion amplifies the host-guest interactions and facilitates the differentiation of organic vapours by their polarity and sizes/shapes, and the covalently linked 3D interwoven networks ensure the robustness and coherency of the materials. The present result paves the way for multiplex fluorescence sensing of various VOCs with molecular-specific responses.

Summary Optical communication and interconnects utilize high-speed light sources for information transmission. The modulation frequency of light-emitting devices operating through spontaneous emission is fundamentally limited by the material intrinsic radiative lifetime. In this perspective, we examine the radiative lifetime of different materials and identify the superradiant molecular J aggregates as a promising class of materials for high-speed light-emitting devices. These molecular aggregates are relatively unexplored for electroluminescent devices and can have short radiative lifetime on the order of 10 ps while maintaining high photoluminescence quantum yield. The relation between intermolecular interactions, molecular packing geometry, and radiative lifetimes is presented theoretically in the context of Frenkel excitons and is corroborated with experimental examples. We further demonstrate the potential of designing superradiant materials through molecular engineering. We believe that these superradiant molecular materials will open up new opportunities in the fabrication of efficient and high-speed light-emitting devices.

The structural development of novel carbon materials has always been a hot spot in theoretical and experimental research, due to carbon possess a wide range of applications in the fields of industry and electronic technology. In this work, an sp 2 + sp 3 hybrid carbon allotrope, named tower carbon, is proposed and studied based on density functional theory, including its structure, stability, electronic and mechanical properties. The crystal structure of tower carbon is like a Chinese classical architectural tower, so it is named tower carbon, which belongs to the cubic crystal system, and it is stable in thermodynamics, dynamics, and mechanics. The electronic band structure of tower carbon is calculated by Heyd–Scuseria–Ernzerhof hybrid functional. The results show that tower carbon is metallic material. In addition, the anisotropy factor of tower carbon and the directional dependence of Young’s modulus, shear modulus, and Poisson’s ratio are estimated. Compared with cF320, the tower carbon has less anisotropy.

The range of luminescent materials that can be used in electroluminescent devices is limited due to material processing challenges and band alignment issues. This impedes the development of electroluminescent devices at extreme wavelengths and hinders the use of electroluminescence spectroscopy as an analytical technique. Here, we show that a two-terminal device that uses an array of carbon nanotubes as the source contact can excite electroluminescence from various materials independent of their chemical composition. Transient band bending, created by applying an a.c. gate voltage, is used to achieve charge injection across different band alignments. As a result, the device can produce electroluminescence from long-wave infrared (0.13 eV) to ultraviolet (3.3 eV) wavelengths depending on the emitting material drop-casted on top of the nanotube array, and with onset voltages approaching the optical energy gap of the emitting material. We show that our device can be used to probe a chemical reaction in a liquid droplet via electroluminescence spectroscopy and can be used as an electroluminescence sensor for detecting organic vapours. A two-terminal device that uses an array of carbon nanotubes as the source contact can excite electroluminescence from a variety of materials, producing electroluminescence from long-wave infrared to ultraviolet wavelengths, with onset voltages approaching the optical energy gap of the emitting material.

Yellowing is one of the main problems of quality deterioration in the storage, transportation, and sales of post-harvested broccoli, which seriously affects the commodity value of broccoli. Therefore, it is of significance to understand the mechanism of the process and develop effective regulation technology. In this review, we expounded the changes in the appearance of the flower ball, bud morphology, and calyx cell structure, as well as endogenous pigment metabolism, accompanying the yellowing process of broccoli. In addition, recent research on the molecular mechanism of yellowing was summarized from the aspects of transcriptome analysis and transcription regulation. Finally, the progress on the control technology of broccoli yellowing was reviewed.

Bell peppers are susceptible to chilling injury (CI). To uncover the metabolism of membrane lipid fatty acids (FAs) accompanying CI, a gas chromatography-mass spectrometry (GC-MS)-based approach was used to quantitatively profile major membrane lipid FAs in bell peppers. RT-qPCR was performed to investigate the expression of the key genes that regulate the synthesis of unsaturated FAs. Additionally, we used microstructural, organoleptic, and physicochemical investigations to monitor the primary physiological metabolism of bell peppers. The study revealed that CI symptoms mostly resulted from the destabilization of the cytomembrane, which was induced by decreasing FA desaturation. Moreover, three times lower level of the double bond index in chilled fruits, than the control, further proved that membrane FA unsaturation can be considered a key factor during CI. In conclusion, this study revealed that the metabolism of membrane lipid FAs is involved in responses to CI.

BackgroundIntestinal health is an important guarantee for the healthy development of mammals. Therefore, the research on intestinal development and function continues to be a hot spot. And intestinal organoids are a hopeful alternative for the intestine, especially in large animals. In this study, we selected intestine of fetus calves as a target to study the differences in intestinal development and the development and functions of organoids in vitro, which were less reported in the past. The fetus intestine tissue is considered a preferred source for obtaining organoid because of its sterility and excellent developmental potential. MethodsWe compared the morphology of crypts and epithelial cells from duodenum, jejunum, ileum and colon at 4-6 month age fetus calves by HE staining, immunohistochemistry and transmission electron microscopy. And we cultured organoids from jejunum tissue and analyzed the structure by optical and electronic microscopy, immunological methods. Subsequently, through RNA sequencing, we confirmed the characteristics of gene expression between organoids and crypts. ResultsThe results showed the villus of jejunum and ileum was significantly higher than others, but the depth of the duodenum crypt was significantly deeper than the other two (P5 and CTNNB1 were highly expressed in the epithelium, but there was significant difference in villus and crypt of different intestinal segments. And By electron microscopy, we noticed that crypt stem cells were typically long and arranged in single and multiple layers closely, with a big nucleus and a large number of microvilli at the top of the cells. Each cell contained a large number of organelles, such as mitochondria and ribosomes. There are more free ribosomes in jejunum, ileum and colon crypt. Some Paneth cells and goblet cells were interspersed among crypt cells. There are typical tight junctions and adherent junctions (fingers cross pattern) between crypt cells. In addition, we obtained jejunum organoids by tissue culture possessing similar traits, such as microvillus and cell tight junctions. CTNNB1, PCNA and Lyso were highly expressed in the crypt cells around the surface of the organoids which hinted at the prominent capacity of cell proliferation. Furthermore, according to RNA sequencing, we found metabolism-related genes were significantly higher expression in organoids than in crypt stem cells (Q

This work presents two novel group 14 element allotropes, oC24 Si24 and oC24 Ge24, and the physical properties of oC24 C24, oC24 Si24, and oC24 Ge24 are studied in detail by means of first-principles calculations. The mechanical stability, dynamic stability, and thermodynamic stability of oC24 Si24 and oC24 Ge24 are proven by the elastic parameters, phonon spectrum, and relative enthalpy, respectively. According to the B/G value, all oC24 C24, oC24 Si24, and oC24 Ge24 are brittle materials. By analysing the directional dependence of Young’s modulus, it is clear that oC24 Si24 possesses the largest mechanical anisotropy. From the electronic properties, it can be concluded that oC24 Si24 is a semiconductor material with a direct band gap of 1.047 eV, which suggests that oC24 Si24 may be suitable to make solar cells. More importantly, the light absorption ability of oC24 Si24 is stronger than that of diamond Si in the visible light region. In addition, the κ min of oC24 Si24 and oC24 Ge24 have better thermal conductivity, indicating that oC24 Si24 and oC24 Ge24 have great application potential in solar cells, optoelectronic devices and other microelectronic devices.

In building integrated photovoltaics (PV), it is important to solve the heat dissipation problem of PV modules. In this paper, the computational fluid dynamics (CFD) method is used to simulate the flow field around the open-joint photovoltaic ventilated double-skin façades (OJ-PV-DSF) to study the influence of the mounting dimensions (MD) of a PV array on the module temperature. The typical summer afternoon meteorological parameters, such as the total radiation (715.4 W/m2), the outdoor temperature (33.1 °C), and the wind speed (2.0 m/s), etc., are taken as input parameters. With the DO (discrete ordinates) model and the RNG (renormalization-group) k−ε model, a steady state calculation is carried out to simulate the flow of air in and around the cavity under the coupling of hot pressure and wind pressure, thereby obtaining the temperature distribution of the PV array and the wall. In addition, the simulation results are compared with the onsite experimental data and thermal imaging to verify the accuracy of the CFD model. Then three MD of the open joints are discussed. The results show that when the a value (represents the distance between PV modules and wall) changes from 0.05 to 0.15, the temperature drop of the PV module is the most obvious, reaching 2.0 K. When the b value (representing the distance between two adjacent PV modules in the vertical direction) changes from 0 to 0.1, the temperature drop of the PV module is most obvious, reaching 1 K. When the c value (represents the distance between two adjacent PV modules in the horizontal direction) changes from 0 to 0.1, the temperature of the PV module is lowered by 0.8 K. Thus, a = 0.1–0.15, b = 0.1 and c = 0.1 are recommended for engineering applications to effectively reduce the module temperature.

To explore the effect of 24-epibrassinolide (EBR) on the postharvest yellowing of broccoli (Brassica oleracea var. italica) florets, these were treated with 0–20 μM EBR and kept at 4 °C for 24 days (shelf life). Changes in color, chlorophyll fluorescence, chloroplast ultrastructure, and in the activities of enzymes and expression of genes related to ethylene synthesis and chlorophyll degradation were determined. Low EBR concentrations (2–5 μM) effectively inhibited the yellowing of broccoli, while high EBR concentrations (15–20 μM) accelerated it. On the 24th day, the grana thylakoids of the chloroplasts of 2 μM EBR-treated florets were neatly arranged and clearly visible, while the chloroplast membrane and grana thylakoids of the chloroplast of 20 μM EBR-treated florets were dissolved. Chlorophyll fluorescence was significantly higher in broccoli florets treated with low EBR concentrations than in control broccoli; the opposite was found for broccoli treated with high EBR concentrations. In 20 μM EBR- treated broccoli, the expressions of the genes coding for 1-aminocyclopropane-1-carboxylic acid (ACC) synthase 4 (BoACS4), ACC oxidase 3 (BoACO3), pheophytinase (PPH), and polyamine oxidase (PaO) were increased, accelerating the degradation of chlorophyll, while in 2 μM EBR-treated broccoli the expressions of BoACS4 and BoACO3 were lower than in control broccoli, thereby reducing the production of endogenous ethylene and delaying yellowing. Thus, treatment with 2 μM EBR extends the shelf life of broccoli.

Bell peppers are valued for their plentiful vitamin C and nutritional content. Pepper fruits are susceptible to cold storage, which leads to chilling injury (CI); however, the crucial metabolic product and molecular basis response to cold stress have not been elucidated definitely yet. To comprehensively understand the gene regulation network and CI mechanisms in response to cold stress on a molecular level, we performed high-throughput RNA-Seq analysis to investigate genome-wide expression profiles in bell peppers at different storage temperatures (4 °C and 10 °C). A total of 61.55 Gb of clean data were produced; 3863 differentially expressed genes (DEGs) including 1669 up-regulated and 2194 down-regulated were annotated and classified between the CI group and control. Together, a total of 41 cold-induced transcription factor families comprising 250 transcription factors (TFs) were identified. Notably, numerous DEGs involved in biomembrane stability, dehydration and osmoregulation, and plant hormone signal transduction processes were discovered. The transcriptional level of 20 DEGs was verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Our results present transcriptome profiles of bell peppers in response to cold stress; the data obtained may be useful for the identification of key candidate genes and elucidation of the mechanisms underlying membrane damage during chilling injury.

Ethylene and ethylene absorber treatments were used to study the effects of ethylene content on the morphology and pigmentation of broccoli. Results showed that untreated broccoli began to turn yellow 8 days after being harvested at 10 °C. Ethylene treatment caused yellowing to occur 2 days earlier, and ethylene absorber treatment delayed and significantly reduced the degree of yellowing. Yellowing first occurred in the base of the bud; at that time, the shape of the bud had not changed significantly and there was no blooming of the florets. Scanning electron microscopy revealed that the increase in ethylene content caused the calyx cells of broccoli to shrink and that the cell arrangement had become disordered. Ethylene treatment caused increases in the content of chlorophyllide b (Chlide b), pheophorbide b (Pheide b), β-cryptoxanthin, lutein, and β-carotene. The increased degree of yellowing resulted in carotenoids rather than chlorophyll becoming the key pigment (β-cryptoxanthin, β-carotene, and lutein were very significantly correlated with h°). During this change, the expression levels of the BoChl2, BoPaO, BoRCCR, BoPSY, and BoLCYB genes were affected to a greater extent by ethylene. Ethylene absorber treatment did not reduce gene expression, but delayed it. These results indicate that the ethylene absorber only absorbed the ethylene produced and did not directly act on the degradation of chlorophyll. Ethylene also stimulated the expression of BoCCD1 and BoCCD7, resulting in the production of an unknown yellow substance that increased the yellow color of broccoli. In comparison, BoCCD7 expression was more sensitive than BoCCD1.

Postharvest yellowing is the main manifestation in the rapid deterioration of broccoli. Here, we monitored the composition and content changes of glucosinolates accompanying the yellowing process of broccoli to reveal the changes of characteristic bioactive substances along with the appearance changes process. Glucosinolates content was greatly reduced in parallel with the yellowing process. The most prominent reduction was among glucoraphanin and its hydrolysate sulforaphane that decreased by 37 % and 69 %, respectively, during slight yellowing, and up to 85 % and 93 %, respectively when severely yellowed. Among the genes involved in glucoraphanin metabolism pathway, the continuous down-regulation of BoCYP83A1, BoTGG1 and BoTGG2 genes had the most serious impact on the reduction of glucoraphanin and sulforaphane content. Postharvest yellowing influenced the appearance of broccoli commodity, while greatly reduced the nutritional value.

Highly efficient hole injection into a AlGaN quantum well is desirable in nitride deep-ultraviolet light-emitting diodes (DUV LEDs) for high optical performance. In this work, we report the observation of enhanced hole injection in the N-polar AlGaN-based DUV LEDs with compositionally graded p-Al x Ga1−xN (x = 0.65–0.75) by simulation and show that the enhanced hole injection leads to the increase of the peak internal quantum efficiency (IQE) and the significant reduction of efficiency droop at high current density. This work might activate researchers to realize the efficient polarization p-type doping of N-polar AlGaN with high Al content and thus to achieve high performance DUV LEDs experimentally.

Based on density functional theory, a new two-dimensional boron nitride, Pmma BN, is proposed and studied in detail for the first time. The stability of Pmma BN is demonstrated by phonon spectra, ab initio molecular dynamics simulations at 300 and 500 K, and in-plane elastic constants. The orientation dependences of the Young’s modulus and Poisson’s ratio show that Pmma BN has large mechanical anisotropy. Pmma BN is an indirect band gap semiconductor material with a band gap of 5.15 eV, and the hole and electron effective mass have high anisotropy. The electron carrier mobility of Pmma BN along the x and y directions is similar, while the hole carrier mobility along the y direction is more than twice that along the x direction. By studying the effect of uniaxial tensile strain on Pmma BN, the band gap of Pmma BN remains indirect under the uniaxial strain, and its adjustable range reaches 0.64 eV at uniaxial strain along the x direction. When uniaxial strain is applied along the y direction, the positions of the conduction band minimum and valence band maximum change. Pmma BN under uniaxial strain show strong optical absorption capacity in the ultraviolet region. To explore clean energy applications, the thermoelectric properties are also investigated.

Long-term storage of pear fruit at low temperature can retard senescence but may result in pericarp browning. We previously reported that increasing endogenous γ-aminobutyrate (GABA) content by exogenous GABA treatment can maintain mitochondrial structure integrity, thereby alleviating pericarp browning of ‘Nanguo’ pears after cold storage. Here, we tested the effectiveness of Ca2+ treatment on pericarp browning in relation to GABA biosynthesis. Fruit browning was reduced by treatment with Ca2+ after 180 days of storage. Pericarp Ca2+ and calmodulin content in treated fruit increased, and concomitantly, endogenous GABA content, key GABA synthesis-related enzyme activity, and gene expression were upregulated. Moreover, the mitochondrial structure in the pericarp tissue was found to be well preserved. Thus, Ca2+ treatment effectively reduced pericarp browning of refrigerated ‘Nanguo’ pears owing to improvement in the GABA biosynthesis capacity in the fruit.

Immunofluorescence (IF) is a common method used in cell biology. The conventional protocol for IF staining is time and labor-intensive, operator dependent and reagent-consuming. Magnetic Bead (MB)-based microdevices are frequently utilized in cellular assays, but integration of simple and efficient mixing with downstream multi-step manipulation of MBs for automatic IF staining is still challenging. We herein present a portable, inexpensive and integratable device for MB-based automatic IF staining. First, a front-end cell capture step is performed using a 3D-mixing module, which is built upon a novel mechanism named ec-2MagRotors and generates periodically changing 3D magnetic fields. A 5-fold enhancement of cell capture efficiency was attained even with a low bead-to-cell concentration ratio (5 : 1), when conducting magnetic 3D mixing. Second, a 1D-moving module is employed downstream to automatically manipulate MB–cell complexes for IF staining. Further, a simplified protocol for staining of γ-H2AX, a biomarker widely used in evaluation of cell radiation damage, is presented for proof-of-principle study of the magnetic device. Using UVC-irradiated CD4+ cells as samples, our device achieved fully automatic γ-H2AX staining within 40 minutes at room temperature and showed a linear dose–response relationship. The developed portable magnetic device is automatic, efficient, cost-effective and simple-to-use, holding great potential for applications in different IF assays.

Research on advanced glycation end-products (AGEs) and their formation pathways in food processing has gradually increased because AGEs are associated with human health, especially with involvement of lipids. In this study, radicals and glycation products were detected via electron spin resonance (ESR) and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) respectively. The correlation of important intermediates was used to explain the effect of oleic acid (OA) on the glycation products and pathways. The results indicated OA participation decreased the content of stable radicals and glycosyl compounds in Maillard Reaction (MR). The oxidation of OA produced active radicals, and electron transfer caused lysine to transform radical form. These radicals participated in the formation of fructosyllysine (FL) with glucose (Glc) via the MR. The participation of OA is acted as inhibiting the way of Glc autoxidation and promoting the glycation pathway from FL to 3-deoxyglucosone (3-DG) to fluorescent-AGEs. Orthogonal projection to latent structures discriminant analysis results indicated that 3-DG, D-glucosone and methylglyoxal are key products in discriminating the glycation reaction.

Chilling injury (CI) restricts the quality and shelf life of bell pepper fruits; reducing these CI-induced detrimental effects is therefore of high economic and agricultural relevance. Here, we investigated the effects of trisodium phosphate (TSP), salicylic acid (SA), and TSP + SA treatments on pepper fruits under cold stress at 4 °C for 25 d. Combined TSP + SA treatment performed an optimal effect. Specifically, TSP + SA treatment enhanced fatty-acid desaturation efficiency, as indicated by the increased expression of key fatty acid desaturase genes, and higher content of unsaturated fatty acids. Meanwhile, TSP + SA treatment inhibited the CI-induced membrane damage, manifested as lower electrolyte leakage and malondialdehyde content. Furthermore, low field-nuclear magnetic resonance and proline content also revealed that TSP + SA treatment mitigated CI through enhancing water retention in pepper fruits. Collectively, our results may shed new light on optimizing the low-temperature storage conditions of post-harvest peppers.

Refrigeration is used to retard senescence and extend the storage life of 'Nanguo' pears, but fruits subjected to long-term refrigeration are prone to pericarp browning during subsequent shelf life. To uncover the potential effects of membrane lipid changes during fruit pericarp browning, changes in fruit appearance and cell ultrastructure were observed after different storage durations. Membrane lipid content as well as the activity and gene expression of enzymes involved in membrane lipid metabolism and membrane stability were analyzed. Results showed that long-term refrigeration increased the activity and expression of PLD, LOX, lipase, and membrane stability-related genes that promoted membrane lipid degradation and peroxidation, reduced membrane lipid unsaturation, and led to severe browning. Overall, membrane instability induced by disordered membrane lipid metabolism under low temperature stress may account for pericarp browning of cold stored 'Nanguo' pears.

Excitons in two-dimensional (2D) materials are tightly bound and exhibit rich physics. So far, the optical excitations in 2D semiconductors are dominated by Wannier-Mott excitons, but molecular systems can host Frenkel excitons (FE) with unique properties. Here, we report a strong optical response in a class of monolayer molecular J-aggregates. The exciton exhibits giant oscillator strength and absorption (over 30% for monolayer) at resonance, as well as photoluminescence quantum yield in the range of 60–100%. We observe evidence of superradiance (including increased oscillator strength, bathochromic shift, reduced linewidth and lifetime) at room-temperature and more progressively towards low temperature. These unique properties only exist in monolayer owing to the large unscreened dipole interactions and suppression of charge-transfer processes. Finally, we demonstrate light-emitting devices with the monolayer J-aggregate. The intrinsic device speed could be beyond 30 GHz, which is promising for next-generation ultrafast on-chip optical communications., The optical response of inorganic two-dimensional semiconductors is dominated by Wannier-Mott excitons, but molecular systems can host localised Frenkel excitons. Here, the authors report strong optical response in a class of monolayer molecular J-aggregates due to the coherent Coulomb interaction between localised Frenkel excitons.

Introduction Neuropathic pain induced by brachial plexus avulsion (BPA) is a pathological condition. We hypothesized that inhibition of histone deacetylase (HDAC) could suppress BPA-induced neuropathic pain through inhibition of transient reception potential (TRP) overexpression and protein kinase B (Akt)-mediated mammalian target of rapamycin (mTOR) activation. Methods We generated a rat BPA model; administered HDAC inhibitor tricostatin A (TSA) for 7 days postsurgery; and assessed the effects on HDAC expression, Akt phosphorylation, neuroinflammation, and mTOR activation. Results TSA treatment alleviated BPA-induced mechanical hyperalgesia, suppressed Akt phosphorylation, and increased HDAC. We found suppressed proinflammatory cytokine levels, TRPV1 and TRPM8 expression, and mTOR activity in TSA-treated BPA rats. Discussion Our results suggest that altered HDAC and Akt signaling are involved in BPA-induced neuropathic pain and that inhibition of HDAC could be an effective therapeutic approach in reducing neuropathic pain. Muscle Nerve 58: 434-440, 2018.

The blue honeysuckle is a rich source of bioactive compounds. In this study, we obtained a polyphenol-rich blue honeysuckle extract (BHE) and found that cyanidin 3-glucoside and chlorogenic acid accounted for most of its phenolic content. Administration of BHE to mice alleviated silica particle (SP)-induced lung inflammation and reduced the recruitment of macrophages to lungs. BHE also reduced the pro-inflammatory cytokine levels in the bronchoalveolar lavage fluid. In vitro study showed that BHE reduced pro-inflammatory cytokine secretion by macrophages and reduced apoptosis in macrophages. Cell signaling analysis revealed that BHE inhibited p38 and c-Jun N-terminal kinase phosphorylation and decreased the nuclear expression of nuclear factor-κB. BHE treatment also down-regulated the expression of inducible nitric oxide synthase and up-regulated two antioxidant mediators, nuclear factor (erythroid-derived 2)-like 2 and heme oxygenase-1, in macrophages. The findings demonstrated that BHE may serve as a complementary and alternative functional food to prevent SP-induced pulmonary diseases.

As recent developments in noninvasive biosensors spearhead the thrust toward personalized health and fitness monitoring, there is a need for high throughput, cost-effective fabrication of flexible sensing components. Toward this goal, we present roll-to-roll (R2R) gravure printed electrodes that are robust under a range of electrochemical sensing applications. We use inks and electrode morphologies designed for electrochemical and mechanical stability, achieving devices with uniform redox kinetics printed on 150 m flexible substrate rolls. We show that these electrodes can be functionalized into consistently high performing sensors for detecting ions, metabolites, heavy metals, and other small molecules in noninvasively accessed biofluids, including sensors for real-time, in situ perspiration monitoring during exercise. This development of robust and versatile R2R gravure printed electrodes represents a key translational step in enabling large-scale, low-cost fabrication of disposable wearable sensors for personalized health monitoring applications.

We consider linear time-invariant networks with unknown topology where only a manifest subset of the nodes can be directly actuated and measured while the state of the remaining latent nodes and their number are unknown. Our goal is to identify the transfer function of the manifest subnetwork and determine whether interactions between manifest nodes are direct or mediated by latent nodes. We show that if there are no inputs to the latent nodes, the manifest transfer function can be approximated arbitrarily well in the $H_{\infty }$ -norm sense by the transfer function of an autoregressive model and present a least-squares estimation method to construct the autoregressive model from measured data. We show that the least-squares autoregressive method guarantees an arbitrarily small $H_{\infty}$ -norm error in the approximation of the manifest transfer function, exponentially decaying once the model order exceeds a certain threshold. Finally, we show that when the latent subnetwork is acyclic, the proposed method achieves perfect identification of the manifest transfer function above a specific model order as the length of the data increases. Various examples illustrate our results.

We investigated the effect of exogenous glutathione (GSH) on chilling injury (CI) in postharvest bell pepper fruits stored at low temperature and explored the mechanism of this treatment from the perspective of the ascorbate-glutathione (AsA-GSH) cycle. Compared with the control, fruits treated with exogenous GSH before refrigeration displayed only slight CI symptoms and mitigated CI-induced cell damage after 10 d. Moreover, the treated peppers had lower lipid peroxidation product, H2O2, and O2- content than those did the control. Glutathione treatment enhanced the ascorbate-glutathione cycle by upregulating CaAPX1, CaGR2, CaMDHAR1, and CaDHAR1 and the antioxidant enzymes APX, GR, and MDHAR associated with the ascorbate-glutathione cycle. Glutathione treatment also increased ascorbate and glutathione concentrations. Taken together, our results showed that exogenous GSH treatment could alleviate CI in pepper fruits during cold storage by triggering the AsA-GSH cycle and improving antioxidant capacity.

Developing synthetic methodology to crystallize extended covalent structures has been an important pursuit of reticular chemistry. Here, we report a homogeneous synthetic route for imine covalent organic frameworks (COFs) where crystallites emerge from clear solutions without forming amorphous polyimine precipitates. The key feature of this route is the utilization of tert-butyloxycarbonyl group protected amine building blocks, which are deprotected in situ and gradually nucleate the crystalline framework. We demonstrate the utility of this approach by crystallizing a woven covalent organic framework (COF-112), in which covalent organic threads are interlaced to form a three-dimensional woven framework. The homogeneous imine COF synthesis also enabled the control of nucleation and crystal growth leading to uniform nanocrystals, through microwave-Assisted reactions, and facile preparation of oriented thin films., Material synthesis and characterization was supported by BASF SE (Ludwigshafen, Germany) and King Abdulaziz City for Science and Technology as part of a joint KACST–UC Berkeley collaboration (Center of Excellence for Nanomaterials and Clean Energy Applications). Work performed at the Advanced Light Source (beamline 7.3.3 and 11.3.1) and at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under contract no. DE-AC02-05CH11231. We also acknowledge the Kavli energy nanoscience institute at UC Berkeley for support of research on nanostructuring of reticular materials. Y.M. and O.T. acknowledge support from ShanghaiTech Startup Funding and Shanghai Science and Technology Committee (17ZR1418600), Y.Z. acknowledges support from a SIP fellowship. L.G. acknowledges support from the Army Research Office for the Multidisciplinary University Research Initiatives award WG11NF-15-1-0047. F.G. acknowledges the Spanish Ministry of Economy and Competitiveness for funding through the Ramón y Cajal program.

This paper studies Gramian-based reachability metrics for bilinear control systems. In the context of complex networks, bilinear systems capture scenarios where an actuator not only can affect the state of a node but also interconnections among nodes. Under the assumption that the input's infinity norm is bounded by some function of the network dynamic matrices, we derive a Gramian-based lower bound on the minimum input energy required to steer the state from the origin to any reachable target state. This result motivates our study of various objects associated with the reachability Gramian to quantify the ease of controllability of the bilinear network: the minimum eigenvalue (worst-case minimum input energy to reach a state), the trace (average minimum input energy to reach a state), and its determinant (volume of the ellipsoid containing the reachable states using control inputs with no more than unit energy). We establish an increasing returns property of the reachability Gramian as a function of the actuators, which, in turn, allows us to derive a general lower bound on the reachability metrics in terms of the aggregate contribution of the individual actuators. We conclude by examining the effect on the worst-case minimum input energy of the addition of bilinear inputs to difficult-to-control linear symmetric networks. We show that the bilinear networks resulting from the addition of either inputs at a finite number of interconnections or at all self loops with weight vanishing with the network scale remain difficult to control. Various examples illustrate our results.

Passivity is a desirable property of a dynamical system because it implies stability and is invariant under negative feedback and parallel interconnections. Feedback passivation is the process of making a nonpassive system passive through feedback control. In this technical note, we study the problem of feedback passivation when the controller has limited information about the state of the plant. Nonlinear plants that are linear in the control inputs are considered. The main result of the technical note is a certainty equivalence principle: any state feedback controller that ensures closed-loop input-strict passivity with index $\mu$ using the exact state of the plant will also ensure closed-loop stochastic quasi passivity using an estimate of the state, provided that the infinity norm of the estimation error process is bounded by some function of $\mu$ . A corollary is that for linear systems, although passivity is more strict than stability, feedback passivation does not place more constraints on the estimation error and hence does not demand more from the communication channel than mean square stabilization.

Sweat is used to examine fluid and electrolyte loss, ion correlations, and glucose dynamics in healthy and diabetic cohorts., Recent technological advancements in wearable sensors have made it easier to detect sweat components, but our limited understanding of sweat restricts its application. A critical bottleneck for temporal and regional sweat analysis is achieving uniform, high-throughput fabrication of sweat sensor components, including microfluidic chip and sensing electrodes. To overcome this challenge, we introduce microfluidic sensing patches mass fabricated via roll-to-roll (R2R) processes. The patch allows sweat capture within a spiral microfluidic for real-time measurement of sweat parameters including [Na+], [K+], [glucose], and sweat rate in exercise and chemically induced sweat. The patch is demonstrated for investigating regional sweat composition, predicting whole-body fluid/electrolyte loss during exercise, uncovering relationships between sweat metrics, and tracking glucose dynamics to explore sweat-to-blood correlations in healthy and diabetic individuals. By enabling a comprehensive sweat analysis, the presented device is a crucial tool for advancing sweat testing beyond the research stage for point-of-care medical and athletic applications.