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Starch is widely used to prepare biodegradable films due to its superior biocompatibility, low immunogenicity, and renewability. In this work, a novel K

A mixed graph is a graph that can be obtained from a simple undirected graph by replacing some of the edges by arcs in precisely one of the two possible directions. The Hermitian adjacency matrix of a mixed graph G of order n is the n×n matrix H(G)=(hij), where hij=−hji=i (with i=−1) if there exists an arc from vi to vj (but no arc from vj to vi), hij=hji=1 if there exists an edge (and no arcs) between vi and vj, and hij=hji=0 otherwise (if vi and vj are neither joined by an edge nor by an arc). Let λ1(G),λ2(G),…,λn(G) be eigenvalues of H(G). The k-th Hermitian spectral moment of G is defined as sk(H(G))=∑i=1nλik(G), where k≥0 is an integer. In this paper, we deal with the asymptotic behavior of the spectrum of the Hermitian adjacency matrix of random mixed graphs. We will present and prove a separation result between the largest and remaining eigenvalues of the Hermitian adjacency matrix, and as an application, we estimate the Hermitian spectral moments of random mixed graphs.

Fusidane-type antibiotics, represented by helvolic acid, fusidic acid and cephalosporin P1, are fungi-derived antimicrobials with little cross-resistance to commonly used antibiotics. Generation of new fusidane-type derivatives is therefore of great value, but this is hindered by available approaches. Here, we developed a stochastic combinational strategy by random assembly of all the post-tailoring genes derived from helvolic acid, fusidic acid, and cephalosporin P1 biosynthetic pathways in a strain that produces their common intermediate. Among a total of 27 gene combinations, 24 combinations produce expected products and afford 58 fusidane-type analogues, of which 54 are new compounds. Moreover, random gene combination can induce unexpected activity of some post-tailoring enzymes, leading to a further increase in chemical diversity. These newly generated derivatives provide new insights into the structure‒activity relationship of fusidane-type antibiotics. The stochastic combinational strategy established in this study proves to be a powerful approach for expanding structural diversity of natural products., Graphical abstract Chemical diversification of fusidane-type antibiotics was accomplished using a stochastic combinational strategy through random assembly of all the post-tailoring genes derived from helvolic acid, fusidic acid and cephalosporin P1 pathways.Image 1

Cu (II) is one of the most harmful heavy metals in the environment, due to the hazardous effects to aquatic organisms, plants, animals, and human beings. In this work, a novel modified magnetic biochar (MBC@APTES-PAMAM) was prepared by PAMAM dendrimer for the removal of Cu (II). The analysis of structural properties identically demonstrated that the abundant -NH2 groups were successfully loaded onto magnetic biochar surfaces. The sorption kinetics process of Cu (II) onto MBC@APTES-PAMAM was better fitted by the pseudo-second-order model. Langmuir isotherm model was better described for Cu (II) sorption process. MBC@APTES-PAMAM showed outstanding performances on Cu (II) removal, and the maximal adsorption amount was 251.81 mg/g. Adsorption experiment indicated that MBC@APTES-PAMAM had a higher Cu (II) removal efficiency under the pH range from 2 to 8. The adsorption capacity of Cu (II) onto MBC@APTES-PAMAM was decreased in the presence of competing ions. The existence of surfactant and humic acid had great influences on Cu (II) adsorption process. The Cu (II) adsorption mechanism was connected to the -NH2 by complexation reaction, due to the increased electrostatic attraction and bridging influences. In addition, MBC@APTES-PAMAM also exhibited comparable removal performances for COD (70.82%), TN (71.10%), TP (100%), NH3 N (55.03%) and Cu (II) (99.68%) in the practical treatment of landfill leachate. Overall, MBC@APTES-PAMAM is a green, low-cost, and high efficiency adsorbent for Cu (II) removal.

WO3 has a great potential in the field of optoelectronics. Herein, sub-stoichiometric WO3-x thin film is prepared and WO3-x/Si n-n homotype heterojunction with pronounced rectifying behavior is constructed. Moreover, the heterojunction exhibits excellent photodetection characteristics, including a large responsivity of 72.8 A/W, a high specific detectivity of 3.96 × 1011 Jones and fast response times of 5.8 μs/1.27 ms. The mechanism of photoinduced charge separation and transfer in the WO3-x/Si n-n homotype heterojunction is analyzed by Kelivn probe force microscopy. These results suggest that the WO3-x/Si n-n homotype heterojunction is of excellent performance in the field of optoelectronic application.

Although non-convex fuzzy set (FS) has the high potential of great performance in data modeling and controlling, it is seldom used and discussed because the lack of linguistic explanation and normative construction way. To address this problem, we propose a method named “parametric qualitative fuzzy set (PQ FS) plus choice strategy” for the construction and linguistic explanation of non-convex FS, in which PQ FS is a collection of convex FSs with special structure, and choice strategy is an approach to choose convex FSs from PQ FS. Based on this method, a non-convex FS is obtained as the trajectory of a collection of convex FS by choosing specific convex FS under specific situation. Thus, the linguistic explanation of non-convex FS is obtained: using non-convex FSs to represent linguistic variables does not violate the routine of using convex FSs, because it shows that the linguistic variable is just represented by different convex FS at different situation. Theorems are shown to demonstrate that the “PQ FS plus choice strategy” can effectively construct a non-convex FS. Furthermore, “Why a fuzzy logic system (FLS) adopting non-convex FSs may have a higher approximation capability” is discussed by introducing a parametric qualitative FLS (PQ FLS) that is compared with a typical Mamdani FLS as a function approximator. This indicates that non-convex FSs can approximate more extrema in a given universe with smaller partition numbers or fewer rules than convex FSs. Finally, the experimental results verify that a PQ FLS designed with the proposed non-convex FS construction method can outperform traditional convex fuzzy logic controllers (FLCs). Meanwhile, using parallel computing in the model training phase of PQ FLSs can reduce the calculation time compared to single-thread mode.

SummaryMotor chunking is important for motor execution, allowing atomization and efficiency of movement sequences. However, it remains unclear why and how chunks contribute to motor execution. To analyze the structure of naturally occurring chunks, we trained mice to run in a complex series of steps and identified the formation of chunks. We found that intervals (cycle) and the positional relationship between the left and right limbs (phase) of steps inside the chunks, unlike those outside the chunks, were consistent across occurrences. Further, licking by the mice was also more periodic and linked to the specific phases of limb movements within the chunk. Based on these findings, we propose therhythm chunking hypothesis, whereby within chunks, the repetitive movements of many body parts are linked by the rhythm parameters: cycle and phase. The computational complexity of movement may thereby be reduced by adjusting movements as the combination of rhythms.

To explore the effects of combined fenestration of lamina terminalis and Liliequist membrane during surgical clipping on the occurrence of chronic hydrocephalus in patients with ruptured anterior circulation aneurysm.Clinical data of 78 patients with anterior circulation ruptured aneurysms who were treated between June 2018 and January 2021 were retrospectively analyzed. Based on the surgical treatment, patients were divided into 3 groups: clipping group (26 cases); fenestration group (lamina terminalis fenestration combined with clipping, 28 cases); and combination group (lamina terminalis fenestration and Liliequist membrane opening combined with clipping, 24 cases). The incidence of postoperative chronic hydrocephalus, the postoperative hydrocephalus shunt rate, and the Glasgow prognostic score (GOS) were evaluated.The incidence of postoperative chronic hydrocephalus in the combined group (16.6 %, 4/24) was significantly lower than that in the clipping group (46.1 %, 12/26) and the fenestration group (35.7 %, 10/28; P 0.05). The shunt rate of chronic hydrocephalus in the combined group (4.1 %, 1/24) was significantly lower than that in the clipping group (30.7 %, 8/26) and the fenestration group (17.8 %, 5/28; P 0.05). The rate of postoperative GOS score of 5 in the combined group (75.0 %, 18/24) was significantly higher than that in the clipping group (23.0 %, 6/26) and the fenestration group (57.1 %, 16/28; P 0.05).Aneurysm clipping combined with lamina terminalis fenestration and Liliequist membrane opening can reduce the occurrence of chronic hydrocephalus and the rate of chronic hydrocephalus shunt surgery, thereby improving the prognosis of patients.

Glioma is the most common tumor in the central nervous system, which is often accompanied by poor prognosis. Brain extracellular matrix (ECM) plays an important role in regulating the growth and migration of glioma. Photodynamic therapy (PDT) has been an effective method for the treatment of solid tumors by oxidative modifications in recent years, and ECM may have an impact on the cytotoxicity of photodynamic therapy. In this work, we prepared decellularized brain ECM by chemical method to investigate the influence of the photodynamic effect of glioma C6 cells. Compared with decellularized liver ECM, brain ECM reduces PDT cytotoxicity. By observing the content of reactive oxygen species produced by near-infrared light active indocyanine green in cells, it was found that ECM did not affect the production of reactive oxygen species. Therefore, it is speculated that brain ECM may enhance the oxidative stress adaptability of glioma cells through potential signal regulation, or protect photodynamic targeting biomolecules (such as proteins and other cellular components) from oxidation in PDT mediated by indocyanine green and 808 nm laser in glioma cells.

Lemna minor could tolerate and accumulate more than 5,000 μg g−1 DW of cobalt (Co) without foliar symptoms, indicating it is a Co hyperaccumulator. However, the physiological and metabolomics mechanisms that are responsible for Co accumulation and tolerance are largely unknown. In the present study, Fourier transform infrared spectroscopy suggested that C O, C H, and O H groups are involved in Co biosorption. The activation of antioxidant enzymes, such as superoxide dismutase, guiacol peroxidase, catalase, and glutathione reductase, as well as ascorbic acid and glutathione might be involved in capturing reactive oxygen species as evidenced by decreased malondialdehyde in fronds treated with Co. Metabolomics analysis revealed that Co stress significantly increased the production of several amino acids (except aspartic acid and cysteine at 200 μM) and organic acids (with the exception of succinic acid). In particular, an approximate 15-fold increase was noted in the citric acid concentration. Upon exposure to Co, increases were observed in citrate synthase, malate dehydrogenase, and phosphoenolpyruvate carboxylase activities, and a decrease was observed in isocitrate dehydrogenase related to the metabolism of organic acids. Overall, the increase in concentration of organic and amino acids and antioxidants support their effective involvement in improving Co tolerance and accumulation in L. minor.

The mammalian circulatory system comprises both the cardiovascular system and the lymphatic system. In contrast to the closed, high-pressure and circular blood vascular circulation, the lymphatic system forms an open, low-pressure and unidirectional transit network from the extracellular space to the venous system. It plays a key role in regulating tissue fluid homeostasis, absorption of gastrointestinal lipids, and immune surveillance throughout the body. Despite the critical physiological functions of the lymphatic system, a complete understanding of the lymphatic vessels lags far behind that of the blood vasculatures due to the challenge of their visualization. During the last 20 years, discoveries of underlying genes responsible for lymphatic vessel biology, combined with state-of-the-art lymphatic function imaging and quantification techniques, have established the importance of the lymphatic vasculature in the pathogenesis of cardiovascular diseases including lymphedema, obesity and metabolic diseases, dyslipidemia, hypertension, inflammation, atherosclerosis and myocardial infraction. In this review, we highlight the most recent advances in the field of lymphatic vessel biology, with an emphasis on the new identification techniques of lymphatic system, pathophysiological mechanisms of atherosclerosis and myocardial infarction, and new therapeutic perspectives of lymphangiogenesis.

This study was undertaken to examine the regulatory role of multidrug resistance-associated protein 4 (MRP4) in an experimental model of sepsis-induced acute lung injury in rats. Sepsis was induced by cecal ligation and puncture in anesthetized rats. Animals were then randomly assigned to receive intravenous injection of vehicle or MRP4 inhibitor (MK571, 20 mg/kg). The pathological changes were observed by hematoxylin and eosin staining. Lung water content, lung vascular permeability and inflammatory cell count in bronchoalveolar lavage fluid (BALF) were quantified. Serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels were measured. In addition, lung tissue cyclic adenosine monophosphate (cAMP) levels were examined by enzyme-linked immunosorbent assay. Furthermore, the effects of MRP4 knockdown on lipopolysaccharide (LPS)-induced endothelial permeability and the cytoskeleton of rat pulmonary microvascular endothelial cells (PMVECs) were detected. The protein expression levels of MRP4, Rac1, VE-cadherin, β-catenin and ZO-1 were measured by Western blot analysis. MK571 significantly reduced lung tissue damage, lung water content and lung vascular permeability. Lung tissue cAMP levels were attenuated in MK571-treated animals compared with vehicle controls. MK571 also decreased sepsis-induced inflammatory cell accumulation in BALF. In addition, the MK571 group had significantly lower serum TNF-α and IL-6 levels compared with vehicle controls. Consistently, knockdown of MRP4 protected against LPS-induced increase in the endothelial permeability and the destruction of cytoskeleton in vitro. Furthermore, silencing MRP4 gene significantly reduced MRP4 protein expression and restored the protein expression of Rac1, VE-cadherin, β-catenin and ZO-1 in rat PMVECs in response to LPS stimulation. These data suggest that inhibition of MRP4 significantly alleviates sepsis-induced acute lung injury in rats.