In-plane graphene/boron-nitride heterostructures as an efficient metal-free electrocatalyst for the oxygen reduction reaction

Exploiting metal-free catalysts for the oxygen reduction reaction (ORR) and understanding their catalytic mechanisms are vital for the development of fuel cells (FCs). Our study has demonstrated that in-plane heterostructures of graphene and boron nitride (G/BN) can serve as an efficient metal-free catalyst for the ORR, in which the C-N interfaces of G/BN heterostructures act as reactive sites. The formation of water at the heterointerface is both energetically and kinetically favorable via a four-electron pathway. Moreover, the water formed can be easily released from the heterointerface, and the catalytically active sites can be regenerated for the next cycle. Since G/BN heterostructures with controlled domain sizes have been successfully synthesized in recent reports (e.g. Nat. Nanotechnol., 2013, 8, 119), our results highlight the great potential of such heterostructures as a promising metal-free catalyst for the ORR in FCs

The Humanitarian Spirit of Marxist Environmental Philosophy

The purpose of the article is to discuss the humanitarian spirit of Marxist environmental philosophy and correct the two extremes of modern human environmental philosophy—non anthropocentrism and anthropocentrism on humanitarian mistake cognition; and dialectically manifests that protecting the environment and showing humanitarianism is not conflict. Protecting the environment does not mean to harm the rights of people, and showing humanitarianism does not mean to destroy the ecological environment. To solve the current ecological environment crisis and let people know the dealing with the relation between man and nature, it not only can protect the natural environment, but also does not harm people’s basic rights and interests, values. It is contrary to the humanitarian spirit; it is aimed to build a green, humane and harmonious society finally

SIRT3: A New Regulator of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading causes of death worldwide, and defects in mitochondrial function contribute largely to the occurrence of CVDs. Recent studies suggest that sirtuin 3 (SIRT3), the mitochondrial NAD+-dependent deacetylase, may regulate mitochondrial function and biosynthetic pathways such as glucose and fatty acid metabolism and the tricarboxylic acid (TCA) cycle, oxidative stress, and apoptosis by reversible protein lysine deacetylation. SIRT3 regulates glucose and lipid metabolism and maintains myocardial ATP levels, which protects the heart from metabolic disturbances. SIRT3 can also protect cardiomyocytes from oxidative stress-mediated cell damage and block the development of cardiac hypertrophy. Recent reports show that SIRT3 is involved in the protection of several heart diseases. This review discusses the progress in SIRT3-related research and the role of SIRT3 in the prevention and treatment of CVDs

Finite-Time H

This paper addresses the problem of finite-time H∞ filtering for one family of singular stochastic systems with parametric uncertainties and time-varying norm-bounded disturbance. Initially, the definitions of singular stochastic finite-time boundedness and singular stochastic H∞ finite-time boundedness are presented. Then, the H∞ filtering is designed for the class of singular stochastic systems with or without uncertain parameters to ensure singular stochastic finite-time boundedness of the filtering error system and satisfy a prescribed H∞ performance level in some given finite-time interval. Furthermore, sufficient criteria are presented for the solvability of the filtering problems by employing the linear matrix inequality technique. Finally, numerical examples are given to illustrate the validity of the proposed methodology

A series of nano/micro-sized metal-organic frameworks with tunable photoluminescence properties

Present studies on metal-organic frameworks (MOF) mainly focus on macro-scaled single crystals. However, the realization of MOF nanocrystals via a bottom-up one-step method still remains a significant challenge. Here, hierarchically assembled nanostructures of lanthanide-based MOFs with 1D and 3D morphologies have been successfully fabricated via a simple and rapid solution phase method at room temperature. Upon UV excitation, these nanomaterials exhibit highly efficient tunable luminescence properties, which come from the Eu3+ or Tb3+ ions. Moreover, white-light emission can be achieved by co-activating the organic ligand, Eu3+ and Tb3+ ions in the nano-MOFs. This journal i

Verrucisidinol and Verrucosidinol Acetate, Two Pyrone-Type Polyketides Isolated from a Marine Derived Fungus, Penicillium aurantiogriseum

The new secondary metabolites verrucosidinol (1) and its derivative verrucosidinol acetate (2), together with a potent neurotoxin verrucosidin (3), a congener norverrucosidin (4) and a mixture of two known phytotoxic metabolites terrestric acids (5 and 6), were isolated from the marine derived fungus Penicillium aurantiogriseum. Verrucosidinol has a ring-opened ethylene oxide moiety in the polyene α-pyrone skeleton, and verrucosidinol acetate is its acetate derivative. The chemical structures were determined by comparing with literature data and a combination of spectroscopic techniques, including high resolution mass spectrum and two-dimentional nuclear magnetic resonance spectroscopic analysis

Antibiotic Expenditure by Public Healthcare Institutions in Shandong Province in China, 2012–2016

Background: Overuse of antibiotics may not only increase the burden of antimicrobial resistance, but also accelerate the growth of healthcare expenditures. China has issued a series of policies to improve antibiotic use and reduce the cost of medicine in healthcare institutions. This study aimed to evaluate the trends of antibiotic expenditure in public healthcare institutions in Shandong from 2012 to 2016 and to assess antibiotic expenditure by drug class and the level of healthcare institutions.Methods: We collected data from the centralized bidding procurement (CBP) system in Shandong province between 2012 and 2016. Governmental health facilities including secondary and tertiary hospitals, and urban and rural primary healthcare centers (PHCs) procured antibiotics via this system. Antibiotics were classified according to the Anatomical Therapeutic Chemical (ATC) classification system. Antibiotic expenditure was assessed using total annual expenditure (US dollars) and expenditure per person per year (US dollars).Results: The overall antibiotic expenditure was $717 million in 2016, a 56% increase compared to 2012. Parenteral antibiotics accounted for 84% of the total antibiotic expenditure in 2016. Most of the antibiotics were procured by secondary and tertiary hospitals (33 and 44%, respectively). The expenditures continuously increased in secondary hospitals, tertiary hospitals, and urban PHCs from 2012 to 2016, while antibiotic procurement decreased in urban PHCs since 2015. The third-generation cephalosporins (J01DD) were among the top five ATC classes of antibiotics in all healthcare institutions. Fluoroquinolones (J01MA) were commonly procured by tertiary hospitals, rural and urban PHCs. The expenditure on carbapenems (J01DH) raised sharply in tertiary hospitals.Conclusions: The overall antibiotic expenditure kept increasing in the public healthcare institutions in Shandong. The trends of increasing expenditure began to decline in 2016, which may be associated with antibiotic stewardship initiatives. The expenditure for expensive and critical important classes of antibiotics increased, therefore it is of importance to develop policies on improving the rational use of antibiotics

Toxic Effects of Silica Nanoparticles on Zebrafish Embryos and Larvae

Silica nanoparticles (SiNPs) have been widely used in biomedical and biotechnological applications. Environmental exposure to nanomaterials is inevitable as they become part of our daily life. Therefore, it is necessary to investigate the possible toxic effects of SiNPs exposure. In this study, zebrafish embryos were treated with SiNPs (25, 50, 100, 200 μg/mL) during 4-96 hours post fertilization (hpf). Mortality, hatching rate, malformation and whole-embryo cellular death were detected. We also measured the larval behavior to analyze whether SiNPs had adverse effects on larvae locomotor activity. The results showed that as the exposure dosages increasing, the hatching rate of zebrafish embryos was decreased while the mortality and cell death were increased. Exposure to SiNPs caused embryonic malformations, including pericardial edema, yolk sac edema, tail and head malformation. The larval behavior testing showed that the total swimming distance was decreased in a dose-dependent manner. The lower dose (25 and 50 μg/mL SiNPs) produced substantial hyperactivity while the higher doses (100 and 200 μg/mL SiNPs) elicited remarkably hypoactivity in dark periods. In summary, our data indicated that SiNPs caused embryonic developmental toxicity, resulted in persistent effects on larval behavior. © 2013 Duan et al.published_or_final_versio