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Little seems to be known about the multistable hyperchaotic systems. In this paper, based on the classical Lorenz system, a new Lorenz‐type hyperchaotic system with a curve of equilibria is proposed. Firstly, the local stability of the curve of equilibria is studied, based on this, infinity many singular degenerate heteroclinic cycles are proved numerically coexisting in the phase space of this hyperchaotic system. Secondly, the discovery of lots of coexisting behaviors mean that this hyperchaotic system possess multistability, such as (i) chaotic attractor and periodic attractor, (ii) different periodic attractors, (iii) chaotic attractor and singular degenerate heteroclinic cycle, and (iv) periodic attractor and singular degenerate heteroclinic cycle. Thirdly, in order to study the global dynamical behavior, the technique of Poincaré compactification is used to investigate the dynamics at infinity of this hyperchaotic system. [ABSTRACT FROM AUTHOR]

This paper is devoted to the analysis of complex dynamics of a generalized Lorenz-Stenflo hyperchaotic system. First, on the local dynamics, the bifurcation of periodic solutions at the zero-zero-Hopf equilibrium (that is, an isolated equilibrium with double zero eigenvalues and a pair of purely imaginary eigenvalues) of this hyperchaotic system is investigated, and the sufficient conditions, which insure that two periodic solutions will bifurcate from the bifurcation point, are obtained. Furthermore, on the global dynamics, the explicit ultimate bound sets of this hyperchaotic system are obtained. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hierarchical tubular structures composed of Co3O4 hollow nanoparticles and carbon nanotubes (CNTs) have been synthesized by an efficient multi-step route. Starting from polymer-cobalt acetate (Co(Ac)2) composite nanofibers, uniform polymer-Co(Ac)2@zeolitic imidazolate framework-67 (ZIF-67) core-shell nanofibers are first synthesized via partial phase transformation with 2-methylimidazole in ethanol. After the selective dissolution of polymer-Co(Ac)2 cores, the resulting ZIF-67 tubular structures can be converted into hierarchical CNTs/Co-carbon hybrids by annealing in Ar/H2 atmosphere. Finally, the hierarchical CNT/Co3O4 microtubes are obtained by a subsequent thermal treatment in air. Impressively, the as-prepared nanocomposite delivers a high reversible capacity of 1281 mAh g−1 at 0.1 A g−1 with exceptional rate capability and long cycle life over 200 cycles as an anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Hierarchical tubular structures composed of Co3O4 hollow nanoparticles and carbon nanotubes (CNTs) have been synthesized by an efficient multi-step route. Starting from polymer-cobalt acetate (Co(Ac)2) composite nanofibers, uniform polymer-Co(Ac)2@zeolitic imidazolate framework-67 (ZIF-67) core-shell nanofibers are first synthesized via partial phase transformation with 2-methylimidazole in ethanol. After the selective dissolution of polymer-Co(Ac)2 cores, the resulting ZIF-67 tubular structures can be converted into hierarchical CNTs/Co-carbon hybrids by annealing in Ar/H2 atmosphere. Finally, the hierarchical CNT/Co3O4 microtubes are obtained by a subsequent thermal treatment in air. Impressively, the as-prepared nanocomposite delivers a high reversible capacity of 1281 mAh g−1 at 0.1 A g−1 with exceptional rate capability and long cycle life over 200 cycles as an anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

A simple and versatile method for general synthesis of uniform one-dimensional (1D) M xCo3− xS4 (M=Ni, Mn, Zn) hollow tubular structures (HTSs), using soft polymeric nanofibers as a template, is described. Fibrous core-shell polymer@M-Co acetate hydroxide precursors with a controllable molar ratio of M/Co are first prepared, followed by a sulfidation process to obtain core-shell polymer@M xCo3− xS4 composite nanofibers. The as-made M xCo3− xS4 HTSs have a high surface area and exhibit exceptional electrochemical performance as electrode materials for hybrid supercapacitors. For example, the MnCo2S4 HTS electrode can deliver specific capacitance of 1094 F g−1 at 10 A g−1, and the cycling stability is remarkable, with only about 6 % loss over 20 000 cycles. [ABSTRACT FROM AUTHOR]

A simple and versatile method for general synthesis of uniform one-dimensional (1D) M xCo3− xS4 (M=Ni, Mn, Zn) hollow tubular structures (HTSs), using soft polymeric nanofibers as a template, is described. Fibrous core-shell polymer@M-Co acetate hydroxide precursors with a controllable molar ratio of M/Co are first prepared, followed by a sulfidation process to obtain core-shell polymer@M xCo3− xS4 composite nanofibers. The as-made M xCo3− xS4 HTSs have a high surface area and exhibit exceptional electrochemical performance as electrode materials for hybrid supercapacitors. For example, the MnCo2S4 HTS electrode can deliver specific capacitance of 1094 F g−1 at 10 A g−1, and the cycling stability is remarkable, with only about 6 % loss over 20 000 cycles. [ABSTRACT FROM AUTHOR]

The role of circulatory proteomics in osteoporosis is unclear. Proteome‐wide profiling holds the potential to offer mechanistic insights into osteoporosis. Serum proteome with 413 proteins was profiled by liquid chromatography–tandem mass spectrometry (LC–MS/MS) at baseline, and the 2nd, and 3rd follow‐ups (7704 person‐tests) in the prospective Chinese cohorts with 9.8 follow‐up years: discovery cohort (n = 1785) and internal validation cohort (n = 1630). Bone mineral density (BMD) was measured using dual‐energy X‐ray absorptiometry (DXA) at follow‐ups 1 through 3 at lumbar spine (LS) and femoral neck (FN). We used the Light Gradient Boosting Machine (LightGBM) to identify the osteoporosis (OP)‐related proteomic features. The relationships between serum proteins and BMD in the two cohorts were estimated by linear mixed‐effects model (LMM). Meta‐analysis was then performed to explore the combined associations. We identified 53 proteins associated with osteoporosis using LightGBM, and a meta‐analysis showed that 22 of these proteins illuminated a significant correlation with BMD (p < 0.05). The most common proteins among them were PHLD, SAMP, PEDF, HPTR, APOA1, SHBG, CO6, A2MG, CBPN, RAIN APOD, and THBG. The identified proteins were used to generate the biological age (BA) of bone. Each 1 SD‐year increase in KDM‐Proage was associated with higher risk of LS‐OP (hazard ratio [HR], 1.25; 95% CI, 1.14–1.36, p = 4.96 × 10−06), and FN‐OP (HR, 1.13; 95% CI, 1.02–1.23, p = 9.71 × 10−03). The findings uncovered that the apolipoproteins, zymoproteins, complements, and binding proteins presented new mechanistic insights into osteoporosis. Serum proteomics could be a crucial indicator for evaluating bone aging. [ABSTRACT FROM AUTHOR]

Background: Emerging evidence suggests that animal protein foods may increase the risk of nonalcoholic fatty liver disease (NAFLD). We therefore examined the NAFLD risk reduction related to substituting plant protein foods for animal protein foods. Methods: The cohort in North China included 14,541 participants from the Tianjin Chronic Low‐Grade Systemic Inflammation and Health (TCLSIH) study, and the cohort in South China included 1297 participants from the Guangzhou Nutrition and Health Study (GNHS). Dietary intake was assessed using validated food frequency questionnaires. NAFLD was ascertained by abdominal ultrasound. The Cox model was used to fit the substitution analysis. Results: In the TCLSIH cohort, when replacing one type of animal protein food (eggs, processed meat, unprocessed red meat, poultry, and fish) with an equivalent serving of plant protein foods (nuts, legumes, and whole grains), the replacement of animal protein foods with whole grains showed the strongest benefit; substituting one serving per day of whole grains for an equal amount of eggs (hazard ratio [HR] = 0.89; 95% confidence interval [CI]: 0.79, 1.00), processed meat (HR = 0.76; 95% CI: 0.64, 0.91), unprocessed red meat (HR = 0.90; 95% CI: 0.81, 1.00), poultry (HR = 0.81; 95% CI: 0.72, 0.92), or fish (HR = 0.87; 95% CI: 0.78, 0.97) was associated with a lower risk of NAFLD. In both the TCLSIH and GNHS cohorts, replacing poultry with fish, nuts, legumes, or whole grains was associated with a lower risk of NAFLD. When different numbers of protein foods were simultaneously replaced, the risk reduction of NAFLD was stronger. Conclusions: Our findings suggest that replacing animal protein foods with plant protein foods is related to a significant reduction in NAFLD risk. [ABSTRACT FROM AUTHOR]

A series of soluble π-conjugated small molecules and polymers containing benzodipyrrolidone (BDP) or naphthodipyrrolidone (NDP) units with latent hydrogen-bonding on the main chain is synthesized and characterized. Spectroscopic study confirms that the tert-butyloxycarbonyl ( t-Boc) side unit can be removed by facile thermal annealing treatment, generating the actual hydrogen-bonded compounds. The resulting hydrogen-bonded compounds exhibit distinctly different properties, for instance poorer solubility and smaller bandgap, as compared with their precursors with latent hydrogen-bonding. The single crystal X-ray structure analysis of t-Boc group substituted BDP and NDP indicates that the NDP compounds exhibit better coplanarity and a stronger π-π interaction. The density functional theory computation results of the polymer backbone segments show that the coplanarity of aromatic units is slightly improved. Such a hydrogen-bonding-mediated enhancement of π-π stacking exhibits potential for improving the performance of solution processable organic electronic materials. Hydrogen-bonded polymer P-NDP-FL-2 is an air stable n-type semiconductor with electron mobility 40 times larger than its precursor polymer P-NDP-FL-1 with latent hydrogen-bonding. [ABSTRACT FROM AUTHOR]

The antibiotic resistance crisis underlies globally increasing failures in treating deadly bacterial infections, largely due to the selection of antibiotic resistance genes (ARG) collection, known as the resistome, in human gut microbiota. So far, little is known about the relationship between gut antibiotic resistome and host metabolic disorders such as type 2 diabetes (T2D). Here, metagenomic landscape of gut antibiotic resistome is profiled in a large multiomics human cohort (n = 1210). There is a significant overall shift in gut antibiotic resistome structure among healthy, prediabetes, and T2D groups. It is found that larger ARG diversity is associated with a higher risk of T2D. The novel diabetes ARG score is positively associated with glycemic traits. Longitudinal validation analysis confirms that the ARG score is associated with T2D progression, characterized by the change of insulin resistance. Collectively, the data describe the profiles of gut antibiotic resistome and support its close relationship with T2D progression. [ABSTRACT FROM AUTHOR]

Biological ion channels are known as membrane proteins which can turn on and off under environmental stimulus to regulate ion transport and energy conversion. Rapid progress made in biological ion channels provides inspiration for developing artificial nanochannels to mimic the structures and functions of ion transport systems and energy conversion in biological ion channels. Due to the advantages of abundant pore channels, metal–organic frameworks (MOFs) have become competitive materials to control the nanofluidic transport. Herein, a facile in situ synthesis method is developed to prepare hybrid nanochannels constructed by 2D MOFs and porous anodic aluminum (PAA). The introduction of asymmetries in the chemical composition and surface charge properties gives the hybrid outstanding ion current rectification properties and excellent ion selectivity. A power density of 1.6 W m−2 is achieved by integrating it into a salinity‐gradient‐driven device. With advantages of facile fabrication method and high ion selectivity, the prepared 2D MOFs/PAA hybrid membrane offers a promising candidate for power conversion and water desalination. [ABSTRACT FROM AUTHOR]

Aim The aim of the present study was to examine the association between dietary fat intake and the risk of hip fractures in an elderly Chinese population. Methods A case-control study of 646 patients with newly diagnosed hip fractures and 646 controls, matched by age (±3 years) and sex, was carried out among elderly Chinese (55-80 years) in Guangdong, China. Their dietary fat intake was measured and calculated using a 79-item food-frequency questionnaire. Results After adjusting for potential confounders, a dose-dependent increased risk of hip fractures was found to be associated with higher intakes of total fat, animal fat, saturated fatty acids and mono-unsaturated fatty acids ( P for trend < 0.005). The adjusted odds ratios (95% confidence intervals) for hip fractures from a comparison of extreme quartiles were 1.92 (1.26-2.92) for total fat, 2.60 (1.70-3.99) for animal fat, 1.95 (1.30-2.93) for saturated fatty acids and 2.22 (1.46-3.39) for animal mono-unsaturated fatty acids, respectively. No significant association was observed for plant fat or polyunsaturated fatty acids ( P for trend = 0.063 for plant fat and 0.174 for polyunsaturated fatty acids). Conclusions Our findings suggest that higher consumption of total fat and animal fat rich in saturated fatty acids might increase the risk of hip fractures in elderly Chinese. Geriatr Gerontol Int 2015; 15: 1171-1178. [ABSTRACT FROM AUTHOR]

The ultra-clean and defect-free transfer of chemical vapor deposition (CVD) graphene is essential for its application in electronic devices. Here, we study the influence of commonly used etching solvents during the transfer process, i.e. ammonium persulfate, ferric chloride, and ferric nitrate, on the properties of CVD graphene by Raman spectroscopy. Obvious blue shift and broadening of Raman G and 2D peaks were observed for graphene transferred by ferric chloride and ferric nitrate, as compared to that transferred by ammonium persulfate. These changes are attributed to p-doping as well as reduction of phonon lifetime of graphene in the presence of residue iron compounds during the transfer process. The latter would also introduce a great reduction of thermal conductivity of graphene, e.g. with 76% reduction for graphene transferred by ferric nitrate as compared to that transferred by ammonium persulfate. This work would provide valuable information for the transfer of high-quality CVD graphene. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective Recent research has suggested that body adiposity index ( BAI) correlates more closely with percentage body fat ( PBF) than body mass index ( BMI). Here, we aimed to evaluate BAI's predictive power for PBF and for obesity-associated risk factors in the Chinese population. Subjects A total of 1707 women and 680 men aged 51-77 years were analysed in this community-based cross-sectional study. Measurements Body weight, height, waist circumference ( WC) and hip circumference ( HC) were measured, and BMI and BAI were calculated. Percentage body fat was determined by dual-energy X-ray absorptiometry ( DXA). Blood pressure, fasting lipid profiles, glucose and Carotid ultrasound examination determined intima-media thickness ( IMT) at the common carotid arteries ( CCA) were also measured. Results The Pearson correlation analysis indicated a stronger correlation between BAI and PBF when women and men were pooled together, but this effect disappeared in sex-stratified analysis. Bland-Altman plots suggested that BAI underestimated 5·8% of PBF in women and slightly overestimated 0·28% of PBF in men, but the magnitudes of these biases showed a fat mass-dependent manner. Both the logistic regression and the receiver operating characteristic curve ( ROC) analysis indicated that BAI has an inferior predictive power for the presence of hypertension, dyslipidaemia, metabolic syndrome and CCA-intima-media thickening, compared with BMI and WC. Conclusion We concluded that BAI was neither a better predictor for PBF nor for cardiovascular risks in Chinese population compared with BMI and WC. [ABSTRACT FROM AUTHOR]