Homologous self-organising scale-invariant properties characterise long range species spread and cancer invasion

The invariance of some system properties over a range of temporal and/or spatial scales is an attribute of many processes in nature1, often characterised by power law functions and fractal geometry2. In particular, there is growing consensus in that fat-tailed functions like the power law adequately describe long-distance dispersal (LDD) spread of organisms 3,4. Here we show that the spatial spread of individuals governed by a power law dispersal function is represented by a clear and unique signature, characterised by two properties: A fractal geometry of the boundaries of patches generated by dispersal with a fractal dimension D displaying universal features, and a disrupted patch size distribution characterised by two different power laws. Analysing patterns obtained by simulations and real patterns from species dispersal and cell spread in cancer invasion we show that both pattern properties are a direct result of LDD and localised dispersal and recruitment, reflecting population self-organisation

Quasiparticle band alignment and stacking-independent exciton in MA2_2Z4_4 (M = Mo, W, Ti; A= Si, Ge; Z = N, P, As)

Motivated by the recently synthesized two-dimensional semiconducting MoSi$_2$N$_4$, we systematically investigate the quasiparticle band alignment and exciton in monolayer MA$_2$Z$_4$ (M = Mo, W, Ti; A= Si, Ge; Z = N, P, As) using ab initio GW and Bethe-Salpeter equation calculations. Compared with the results from density functional theory (DFT), our GW calculations reveal substantially more significant band gaps and different absolute quasiparticle energy but predict the same types of band alignments

Impact of CRAMP-34 on Pseudomonas aeruginosa biofilms and extracellular metabolites

Biofilm is a structured community of bacteria encased within a self-produced extracellular matrix. When bacteria form biofilms, they undergo a phenotypic shift that enhances their resistance to antimicrobial agents. Consequently, inducing the transition of biofilm bacteria to the planktonic state may offer a viable approach for addressing infections associated with biofilms. Our previous study has shown that the mouse antimicrobial peptide CRAMP-34 can disperse Pseudomonas aeruginosa (P. aeruginosa) biofilm, and the potential mechanism of CRAMP-34 eradicate P. aeruginosa biofilms was also investigated by combined omics. However, changes in bacterial extracellular metabolism have not been identified. To further explore the mechanism by which CRAMP-34 disperses biofilm, this study analyzed its effects on the extracellular metabolites of biofilm cells via metabolomics. The results demonstrated that a total of 258 significantly different metabolites were detected in the untargeted metabolomics, of which 73 were downregulated and 185 were upregulated. Pathway enrichment analysis of differential metabolites revealed that metabolic pathways are mainly related to the biosynthesis and metabolism of amino acids, and it also suggested that CRAMP-34 may alter the sensitivity of biofilm bacteria to antibiotics. Subsequently, it was confirmed that the combination of CRAMP-34 with vancomycin and colistin had a synergistic effect on dispersed cells. These results, along with our previous findings, suggest that CRAMP-34 may promote the transition of PAO1 bacteria from the biofilm state to the planktonic state by upregulating the extracellular glutamate and succinate metabolism and eventually leading to the dispersal of biofilm. In addition, increased extracellular metabolites of myoinositol, palmitic acid and oleic acid may enhance the susceptibility of the dispersed bacteria to the antibiotics colistin and vancomycin. CRAMP-34 also delayed the development of bacterial resistance to colistin and ciprofloxacin. These results suggest the promising development of CRAMP-34 in combination with antibiotics as a potential candidate to provide a novel therapeutic approach for the prevention and treatment of biofilm-associated infections

Synthesis and characterization of Pst-b-PDMS-b-PSt copolymers by atom transfer radical polymerization

Polystyrene-b-poly(dimethylsiloxane)-b-polystyrene (Pst-b-PDMS-b-PSt) triblock copolymers were synthesized by atom transfer radical polymerization (ATRP). Commercially available difunctional PDMS containing vinylsilyl terminal species was reacted with hydrogen bromide, resulting in the PDMS macroinitiators for the ATRP of styrene (St). The latter procedure was carried out at 130°C in a phenyl ether solution with CuCl and 4, 4-di (5-nonyl)-2,2-bipyridine (dNbpy) as the catalyzing system. By using this technique, triblock copolymers consisting of a PDMS center block and polystyrene terminal blocks were synthesized. The polymerization was controllable; ATRP of St from those macroinitiators showed linear increases in Mn with conversion. The block copolymers were characterized with IR and 1H-NMR. The effects of molecular weight of macroinitiators, macroinitiator concentration, catalyst concentration, and temperature on the polymerization were also investigated. Thermodynamic data and activation parameters for the ATRP are reported

Synthesis and Characterization of Poly(n-butyl methacrylate)-b-Polystyrene Diblock Copolymers by Atom Transfer Radical Emulsion Polymerization

Poly(n-butyl methacrylate) (PBMA)-b-polystyrene (PSt) diblock copolymers were synthesized by emulsion atom transfer radical polymerization (ATRP). PBMA macroinitiators that contained alkyl bromide end groups were obtained by the emulsion ATRP of n-butyl methacrylate with BrCH3CHCOOC2H5 as the initiator; these were used to initiate the ATRP of styrene (St). The latter procedure was carried out at 85°C with CuCl/4,4-di(5-nonyl)- 2,2-bipyridine as the catalyst and polyoxyethylene(23) lauryl ether as the surfactant. With this technique, PBMA-b-PSt diblock copolymers were synthesized. The polymerization was nearly controlled; the ATRP of St from the macroinitiators showed linear increases in number-average molecular weight with conversion. The block copolymers were characterized with IR spectroscopy, 1H-NMR, and differential scanning calorimetry. The effects of the molecular weight of the macroinitiators, macroinitiator concentration, catalyst concentration, surfactant concentration, and temperature on the polymerization were also investigated. Thermodynamic data and activation parameters for the ATRP are also reported

Reverse atom transfer radical polymerization of n-butyl methacrylate in aqueous dispersed system

Reverse atom transfer radical polymerization (ATRP) of n-butyl methacrylate (BMA) was conducted in an aqueous dispersed system. The influence of the surfactant, catalyst, reaction time and temperature on the colloidal stability and the control of polymerization was investigated. As a result, using an azo initiator (AIBN), a non-ionic surfactant (Brij 35) and a hydrophobic ligand (dNbpy) to complex a copper halide, polymers with predetermined molecular weight and low polydispersity were obtained as stable latexes

17β-Estradiol inhibits TNF-α-induced proliferation and migration of vascular smooth muscle cells via suppression of TRAIL

Atherosclerosis is an inflammatory disease and involves migration of vascular smooth muscle cells (VSMCs). Estrogen inhibits VSMCs migration, while the underlying mechanism remains to be revealed. Recent years, there is emerging evidence showing that TNF-related apoptosis-inducing ligand (TRAIL) increases proliferation and migration of VSMCs. In this study, we investigated the regulatory effect of estrogen on TRAIL expression in VSMCs. TNF-α greatly enhanced TRAIL protein expression and stimulated VSMCs proliferation and migration. This effect was partially inhibited by the addition of TRAIL neutralizing antibody, suggesting that TRAIL is important in TNF-α-induced migration. 17β-estradiol (E2) inhibited TRAIL expression under TNF-α stimulation in a time- and concentration-dependent manner. This effect was was mimicked by ERα agonist 4â\u80²,4â\u80³,4â\u80´-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol (PPT), but not ERβ agonist 2,3-bis-(4-hydroxyphenyl)-propionitrile (DPN), indicating that ERα is involved in this action. TNF-α led to nuclear factor kappa B (NF-κB) p65 phosphorylation and the inhibitor pyrrolidine dithiocarbama (PDTC) inhibited TRAIL expression, suggesting that NF-κB signaling is crucial for TARIL production. E2 suppressed p65 phosphorylation in VSMCs and the overexpression of p65 subunit reversed the inhibitory effect of E2 on TRAIL expression and cell proliferation and migration. Taken together, our results indicate that E2 inhibits VSMCs proliferation and migration by downregulation of TRAIL expression via suppression of NF-κB pathway

CDFS: A high-efficiency Data Access System for Storage Federations

High energy physics (HEP) experiments, such as LHAASO, produce a large amount of data, which is usually stored and processed on distributed sites. Nowadays, the distributed data management system faces some challenges such as global file namespace, efficient data access and storage. Focusing on those problems, this paper proposed a cross-domain data access file system (CDFS), applying data deduplication and compression as the storage-optimized engine, aiming at dynamically building an aggregate view of multiple distributed storages and accessing data in a fast and efficient way. The test based on the raw data of LHAASO experiment showed that the CDFS could present a unique repository based on distributed sites in LHAASO. And the storage-optimized engine reduces the storage consumption of the raw data by more than 50%

CDFS: A high-efficiency Data Access System for Storage Federations

High energy physics (HEP) experiments, such as LHAASO, produce a large amount of data, which is usually stored and processed on distributed sites. Nowadays, the distributed data management system faces some challenges such as global file namespace, efficient data access and storage. Focusing on those problems, this paper proposed a cross-domain data access file system (CDFS), applying data deduplication and compression as the storage-optimized engine, aiming at dynamically building an aggregate view of multiple distributed storages and accessing data in a fast and efficient way. The test based on the raw data of LHAASO experiment showed that the CDFS could present a unique repository based on distributed sites in LHAASO. And the storage-optimized engine reduces the storage consumption of the raw data by more than 50%