Cooperative effect of random and time-periodic coupling strength on synchronization transitions in one-way coupled neural system: mean field approach

The cooperative effect of random coupling strength and time-periodic coupling strengh on synchronization transitions in one-way coupled neural system has been investigated by mean field approach. Results show that cooperative coupling strength (CCS) plays an active role for the enhancement of synchronization transitions. There exist an optimal frequency of CCS which makes the system display the best CCS-induced synchronization transitions, a critical frequency of CCS which can not further affect the CCS-induced synchronization transitions, and a critical amplitude of CCS which can not occur the CCS-induced synchronization transitions. Meanwhile, noise intensity plays a negative role for the CCS-induced synchronization transitions. Furthermore, it is found that the novel CCS amplitude-induced synchronization transitions and CCS frequency-induced synchronization transitions are found.     

Ubiquitin-coated nanodiamonds bind to autophagy receptors for entry into the selective autophagy pathway

Selective macroautophagy/autophagy plays a pivotal role in the processing of foreign pathogens and cellular components to maintain homeostasis in human cells. To date, numerous studies have demonstrated the uptake of nanoparticles by cells, but their intracellular processing through selective autophagy remains unclear. Here we show that carbon-based nanodiamonds (NDs) coated with ubiquitin (Ub) bind to autophagy receptors (SQSTM1 [sequestosome 1], OPTN [optineurin], and CALCOCO2/NDP52 [calcium binding and coiled-coil domain 2]) and are then linked to MAP1LC3/LC3 (microtubule-associated protein 1 light chain 3) for entry into the selective autophagy pathway. NDs are ultimately delivered to lysosomes. Ectopically expressed SQSTM1-green fluorescence protein (GFP) could bind to the Ub-coated NDs. By contrast, the Ub-associated domain mutant of SQSTM1 (ΔUBA)-GFP did not bind to the Ub-coated NDs. Chloroquine, an autophagy inhibitor, prevented the ND-containing autophagosomes from fusing with lysosomes. Furthermore, autophagy receptors OPTN and CALCOCO2/NDP52, involved in the processing of bacteria, were found to be involved in the selective autophagy of NDs. However, ND particles located in the lysosomes of cells did not induce mitotic blockage, senescence, or cell death. Single ND clusters in the lysosomes of cells were observed in the xenografted human lung tumors of nude mice. This study demonstrated for the first time that Ub-coated nanoparticles bind to autophagy receptors for entry into the selective autophagy pathway, facilitating their delivery to lysosomes.     

Molecular phylogeny and host-plant use (Lamiaceae) of the Thymogethes pollen beetles (Coleoptera)

The 24 members of the Euro-Asiatic genus Thymogethes are highly specialized pollen beetles associated as larvae with flowers of Lamiaceae Nepetoideae. All members of the genus were analysed in within the framework of an integrative taxonomy approach, which was aimed to reconstruct the phylogenetic relationships, as well as the possible pattern of evolution of their larval-host-plant association. Evidence from multiple molecular markers [COI; 16S; H3], combined with an estimation of divergence times using an average rate of 0.0177 substitutions/site/My among branches, placed the origin of the genus at a minimum of 9–10 Mya. This date of origin approximates the known evolution of the host plants in Euro-Mediterranean areas. Evidence from combined molecular and cladistic morphological analyses resulted in suitable agreement with the previously established morphology-based systematics of the genus, although members of the exilis species-group were split into three clades. The only disagreement between results of this new combined phylogeny and previous classification is in the exclusion of “Thymogethes” grenieri. This species is herein positioned outside the genus, based on molecular evidence. Our analysis depicts several Thymogethes species differentiating in the last few Mys, specifically those included in the T. lugubris species-group. Combined evidence from DNA, morphology and ancestral state parsimony reconstruction of larval-host-plant associations suggests that subtribe Menthinae likely represents the ancestral host plants, with a series of independent host shifts during the radiation of the clade, in association first with Menthinae and subsequently with Lavandulinae and Nepetinae. Steno-oligophagy is the most frequent (86%) condition, while strictly monophagous species are less numerous (14%).     

A Parameter-Elimination Method for Nonlinear Regression with Linear Parameters and Autocorrelated Errors

In this study, we are interested in the problem of estimating the parameters in a nonlinear regression model when the error terms are correlated. Throughout this work, we restrict ourselves to the special case when the error terms follow a pth order stationary autoregressive model (AR(p)). Following the idea of LAWTON and SYLVESTRE (1971) and GALLANT and GOEBEL (1976), a parameter-elimination method is proposed, which has the advantages that it is not sensitive to the initial values and convergence of the procedure may be more stable because of the reduced dimension of the problem. The parameter-elimination method is compared with the methods by GALLANT and GOEBEL (1976) and GLASBEY (1980) by Monte Carlo Simulation, and the results of applying the first two methods to the real data obtained from the Environmental Protection Administration of the Executive Yuan of the Republic of China are presented.     

The Association between Near Work Activities and Myopia in Children—A Systematic Review and Meta-Analysis

Myopia has a multifactorial etiology, although environmental factors are predominant in determining its current patterns. Currently, associations between near work activities and myopia have not been consistently observed. Therefore, we performed a systematic review to quantify the effect of near work activities on myopia in children. Relevant articles published between 1989 and 2014 were identified in MEDLINE, Embase, and the Cochrane Library, and the citation lists were reviewed. Twelve cohort studies and 15 cross-sectional studies were included (25,025 children aged between 6 and 18 years). The I ² statistic was used to assess heterogeneity. Study-level data were pooled using a random-effects model or a fixed-effects model (when less than 5 studies were included). We found that more time spent on near work activities was associated with higher odds of myopia (odds ratio [OR] = 1.14; 95% confidence interval [CI] = 1.08–1.20) and that the odds of myopia increased by 2% (OR:1.02; 95% CI = 1.01–1.03) for every one diopter-hour (hr) more of near work per week. Therefore, the development of a strategy to reduce the impact of near work on myopia would be important for preventing myopia in children.     

A 3-hydroxy-3-methylglutaryl-CoA synthase-based probe for the discovery of the acyltransferase-less type I polyketide synthases

Acyltransferase (AT)-less type I polyketide synthases (PKSs) produce complex natural products due to the presence of many unique tailoring enzymes. The 3-hydroxy-3-methylglutaryl coenzyme A synthases (HCSs) are responsible for β-alkylation of the growing polyketide intermediates in AT-less type I PKSs. In this study, we discovered a large group of HCSs, closely associated with the characterized and orphan AT-less type I PKSs through in silico genome mining, sequence and genome neighbourhood network analyses. Using HCS-based probes, the survey of 1207 in-house strains and 18 soil samples from different geographic locations revealed the vast diversity of HCS-containing AT-less type I PKSs. The presence of HCSs in many AT-less type I PKSs suggests their co-evolutionary relationship. This study provides a new probe to study the abundance and diversity of AT-less type I PKSs in the environment and microbial strain collections. Our study should inspire future efforts to discover new polyketide natural products from AT-less type I PKSs.     

Phylogeny of the Altingiaceae based on cpDNA matK, PY-IGS and nrDNA ITS sequences

 Phylogenetic relationships of the three genera of the family Altingiaceae, i.e., Altingia, Liquidambar and Semiliquidambar, based on matK sequences and the intergenic spacer between the psaA and ycf3 genes (PY-IGS) of cpDNA, and on the internal transcribed spacer (ITS) of nrDNA were studied. Phylogenetic trees based on the three data sets (matK, PY-IGS and ITS) were generated using Hamamelis japonica and Mytilaria laosensis (Hamamelidaceae), Cercidiphyllum japonicum (Cercidiphyllaceae), and Daphniphyllum calycinum (Daphniphyllaceae) as outgroups. The partition-homogeneity tests indicated that the three data sets and the combined data are homogeneous. A combined analysis also generated a strongly supported phylogeny. The phylogenetic trees show that the North American and western Asian species, L. styraciflua and L. orientalis, respectively, form a monophyletic group which is sister to the clade including all Asian species in the family. The genus Liquidambar is paraphyletic with Altingia and Semiliquidambar nested within. Phylogenetic analyses of the molecular data indicate that taxonomic reexamination of the generic delimitation in the Altingiaceae is needed. Received December 20, 2000 Accepted June 25, 2001     

Single-cell landscape of the ecosystem in early-relapse hepatocellular carcinoma

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