A nitrogen-doped NiCo2S4/CoO hollow multi-layered heterostructure microsphere for efficient oxygen evolution in Zn-air batteries.

Exploring highly effective and low-cost non-noble metal-based electrocatalysts for oxygen evolution reaction (OER) is critical for renewable energy conversion and metal-air batteries. Herein, a novel and high-efficient OER catalyst was reported with nitrogen-doped oxide/sulfide heterostructures (named N-NiCo2S4/CoO microsphere). The N-NiCo2S4/CoO microsphere was synthesized by annealing NiCo-BTC MOF to a multi-layered hollow structure of NiCo2O4 microspheres, followed by the direct vulcanization in the presence of NH4HCO3, resulting in an oxide/sulfide heterojunction. Benefiting from the nitrogen doping, the abundant multi-layered hollow heterostructure and the interfaces between multiple components, the N-NiCo2S4/CoO microsphere exhibited excellent OER activity with a low overpotential of 227 mV at 10 mA cm-2. The Zn-air battery based on the N-NiCo2S4/CoO + Pt/C catalyst displayed excellent cycling stability after 900 cycles at a large current density of 5 mA cm-2, where the commercial RuO2 + Pt/C-based battery exhibited a big drop after only 30 cycles, suggesting its great application prospects as power source devices.

Prevalence and Treatment of Children's Asthma in Rural Areas Compared with Urban Areas in Beijing.

BACKGROUND: The prevalence of childhood asthma has been increasing in China. This study aimed to compare the prevalence, diagnosis, and treatment of asthmatic children from urban and rural areas in Beijing, China. METHODS: Schools, communities, and kindergartens were randomly selected by cluster random sampling from urban and rural areas in Beijing. Parents were surveyed by the same screening questionnaires. On-the-spot inquiries, physical examinations, medical records, and previous test results were used to diagnose asthmatic children. Information on previous diagnoses, treatments, and control of symptoms was obtained. RESULTS: From 7209 children in rural areas and 13,513 children in urban areas who completed screening questionnaires, 587 children were diagnosed as asthma. The prevalence of asthma in rural areas was lower than in urban areas (1.25% vs. 3.68%, χ2 = 100.80, P < 0.001). The diagnosis of asthma in rural areas was lower than in urban areas (48.9% vs. 73.9%, χ2 = 34.6, P < 0.001). Compared with urban asthmatic children (56.5%), only 35.6% of rural asthmatic children received inhaled corticosteroids (P < 0.05). The use of bronchodilators was also lower in rural areas than in urban areas (56.5% vs. 66.4%, χ2 = 14.2, P < 0.01). CONCLUSION: The prevalence of asthma in children was lower in rural areas compared with children in the urban area of Beijing. A considerable number of children were not diagnosed and inadequately treated in rural areas.

[Epidemiological survey of children asthma prevalence in Beijing urban area].

OBJECTIVE: To explore the prevalence, diagnosis and management of childhood asthma in Beijing urban area. METHODS: Multi-stage, stratified and random cluster sampling was used to recruit children born during November 1, 1995 to October 31, 2010 from Beijing or other provinces but residing in Beijing for over half a year. The same screening questionnaires for the third national epidemiological survey of children's asthma were distributed to parents of children at schools, kindergartens and communities during October 2010 to March 2011. Asthmatic children were picked among the screening-positive children based on on-the-spot inquiries, physical examinations, medical records and supporting test results. Further survey of asthmatics was carried out to investigate the diagnosis and treatment status of childhood asthma and other associated allergic diseases. All data required double entry by Epi-Info 3.5.3 software and were processed by SPSS 19.0. RESULTS: Among a total of 14 085 questionnaires, 13 513 were completed with a response rate of 95.94%. And 497 (3.68%) children were diagnosed with typical (n = 451, 3.34%) and cough variant (n = 46, 0.34%) asthma. Among them, 40.64% (202/497) were newly diagnosed and 59.36% (295/497) had been previously diagnosed with asthma. The prevalence of asthma was higher in boys than in girls (4.80% (345/1790) vs 2.40% (152/6323), χ(2) = 54.446, P < 0.01). The asthma prevalence of preschoolers (3 - < 7 years old) was the highest (5.05% (180/3563)). In the past two years, the symptoms of 69.42% (345/497) children persisted and the current two-year prevalence of asthma was 2.55% (345/13513). Among the 295 children with previous asthma, only 46.44% (137/295) received inhaled corticosteroids according to the Global Initiative for Asthma (GINA) and 82.37% (243/295) of them used antibiotics. CONCLUSIONS: The prevalence of asthma is 3.68% in children under 14 years old in Beijing urban area and it varies in children with different genders and ages. A considerable number of children are not diagnosed or treated properly. And the management of asthma requires further improvement.

Association of polymorphisms of STAT6 and SO(2) with Chinese childhood asthma: a case-control study.

OBJECTIVE: To investigate the association of polymorphisms of STAT6 gene and air pollutants of PM(10), NO(2), and SO(2), with asthma in Chinese children. METHODS: 418 subjects aged 14 years and under were recruited in a case-control study. The association between STAT6 polymorphisms and childhood asthma were tested by allele frequency, genotype analysis, and MDR analysis. Exposure to outdoor air pollutants was estimated by a 5-day moving average level. Statistical analyses were performed with SAS 9.1 software. RESULTS: Only 3 alleles of GT repeats at exon 1 of STAT6 were found in Chinese children. C258T and T710C were 2 new SNPs of STAT6 at 3'-UTR. Children who carried T allele of C258T were more common in asthma children than in control subjects (P<0.05). The MDR analysis showed that GT repeats, C258T and T710C of STAT6 polymorphisms interacted together in leading to susceptibility to childhood asthma among Chinese people. After confounding factors were controlled, such as SNP C258T, family history of asthma, frequency of influenza within a year, the 5-day average of SO(2) was tested to be a key risk factor of asthma in Chinese children (P<0.05). CONCLUSION: Chinese children differed in polymorphisms of STAT6 and in its relation with childhood asthma.