Time trends and risk factor associated with premature birth and infants deaths due to prematurity in Hubei Province, China from 2001 to 2012

Background: The nutrition and epidemiologic transition has been associated with an increasing incidence of preterm birth in developing countries, but data from large observational studies in China have been limited. Our study was to describe the trends and factors associated with the incidence of preterm birth and infant mortality due to prematurity in Hubei Province, China. Methods: We conducted a population-based survey through the Maternal and Child Health Care Network in Hubei Province from January 2001 to December 2012. We used data from 16 monitoring sites to examine the trend and risk factors for premature birth as well as infant mortality associated with prematurity. Results: A total of 818,481 live births were documented, including 76,923 preterm infants (94 preterm infants per 1,000 live births) and 2,248 deaths due to prematurity (2.75 preterm deaths per 1,000 live births). From 2001 to 2012, the incidence of preterm birth increased from 56.7 to 105.2 per 1,000 live births (P for trend < 0.05), while the infant mortality rate due to prematurity declined from 95.0 to 13.4 per 1,000 live births (P for trend < 0.05). Older maternal age, lower maternal education, use of assisted reproductive technology (ART), higher income, residence in urban areas, and infant male sex were independently associated with a higher incidence of preterm birth (all p values < 0.05). Shorter gestation, lower birth weight, and lower income were associated with a higher mortality rate, while use of newborn emergency transport services (NETS) was associated with a lower preterm mortality rate (all p values < 0.05). Conclusion: An increasing incidence of preterm birth and a parallel reduction in infant mortality due to prematurity were observed in Hubei Province from 2001 to 2012. Our results provide important information for areas of improvements in reducing incidence and mortality of premature birth. Electronic supplementary material The online version of this article (doi:10.1186/s12884-015-0767-x) contains supplementary material, which is available to authorized users

A New Graph Representation of Assembly Planning

Abstract- To express nonlinear assembly sequences, a logical tree model for assembly sequences planning is proposed after analyzing the disadvantage of the existing method to generate and express of assembly sequence. Meanwhile, based on the information of the function structure tree and its parts and components of the production, the broad sense sub-assembly is identified by dividing the assembly relation graph and matching the rule. So, the identification of broad sense sub-assembly is simplified. Then, the preferential constraint relation of parts of broad sense sub-assembly is judged by matching assembly knowledge. Finally, based on the function structure tree, the data node and the relation node are continually added. From the top layer to the bottom layer, the tree for expressing assembly sequences is created in turn

Secondary Metabolites from the Endoparasitic Nematophagous Fungus Harposporium anguillulae YMF 1.01751

Harposporium anguillulae, an endoparasitic nematophagous fungus (ENF), is a model fungus from which the genus Harposporium was established. It can infect nematodes via ingested conidia. In this paper, the morphology and nematode&ndash;fungus interaction between Panagrellus redivivus and H. anguillulae were observed by scanning electron microscopy (SEM). The secondary metabolites of H. anguillulae were also studied. Seven metabolites were purified and identified from an ethyl acetate extract of broth and a methanol extract of mycelium. These include a new polyketone 5-hydroxy-3-(hydroxymethyl)-6-methyl-2H-pyran-2-one (1) and six known metabolites (17R)-17-methylincisterol (2), eburicol (3), ergosterol peroxide (4), terpendole C (5), (3&beta;,5&alpha;,9&beta;,22E)-3,5-dihydroxy-ergosta-7,22-dien-6-one (6), and 5&alpha;,6&beta;-epoxy-(22E,24R)-ergosta-8,22-diene- 3&beta;,7&alpha;-diol (7). These metabolites were assayed for their activity against plant root-knot nematode, Meloidogyne incognita, and the results showed that terpendole C (5) had weak nematicidal activity but also that other compounds did not have evident activity at a concentration of 400 &mu;g mL&minus;1. Compound 1 exhibited an attractive effect towards P. redivivus

Stress tunable magnetic stripe domains in flexible Fe81Ga19 films

In this paper, we propose an approach that combines in situ mechanical-stress measurement and magnetic force microscopy (MFM) imaging and enable manipulation of the spin configuration of flexible films by tailoring the stress-induced anisotropy. We demonstrate that the stress-induced anisotropy can effectively rotate stripe domains. We see that, without the application of the magnetic field, the stripe domains tend to align parallel (perpendicular) to the direction of tensile (compressive) stress. The expansion (shrinkage) of flux-closure cap domains in response to applied tensile (compressive) stress, changes the out-of-plane stray field and the profile in the MFM image. The experimental results have been reproduced very well by micromagnetic simulations assuming a stress-induced anisotropy. Furthermore, we studied the evolution of stripe domains in the film with compressive stress against a decreasing magnetic field. It is indicated that in-plane mechanical stress can effectively convert stripe domains with Bloch walls to those with Neel walls. The observed stress-modulation of magnetic stripe domains may find application in microwave absorbers and flexible electronics

Pathogenicity and Metabolites of Endoparasitic Nematophagous Fungus Drechmeria coniospora YMF1.01759 against Nematodes

Plant parasitic nematodes cause severe damage to crops. Endoparasitic nematophagous fungi (ENF) are a type of important biocontrol fungi, which can cause disease or kill nematodes by producing various spores. As a major ENF, Drechmeria coniospora displays certain potential for controlling plant-parasitic nematodes. In this study, the pathogenicity and secondary metabolites of the endoparasitic fungus D. coniospora YMF1.01759 were investigated. The strain D. coniospora YMF1.01759 had high infection efficiency against nematodes. The process of infecting nematodes by the strain was observed under an electron microscope. Here, 13 metabolites including one new compound 4(S)-butoxy-3-(butoxymethyl)-2-hydroxycyclopent-2-en-1-one (2) were isolated and identified from the fermentation products of D. coniospora YMF1.01759 cultured in a SDAY solid medium. Furthermore, a bioassay showed that 5-hydroxymethylfuran-2-carboxylic acid (1) is toxic to the root knot nematode Meloidogyne incognita and affects the hatching of its egg. Thereby, the nematicidal mortality attained 81.50% at 100 μg/mL for 48 h. Furthermore, egg hatching was inhibited at the tested concentrations, compared with water control eggs. This is the first report on the secondary metabolites of the ENF D. coniospora. The results indicated that D. coniospora could infect nematodes by spores and produce active metabolites to kill nematodes. The biological control potential of D. coniospora against nematodes was expounded further

Social-Based Cooperative Caching in DTNs: A Contact Duration Aware Approach

Abstract—Data access is an important issue in Delay Tolerant Networks (DTNs), and a common technique to improve the performance of data access is cooperative caching. However, due to the unpredictable node mobility in DTNs, traditional caching schemes cannot be directly applied. In this paper, we propose DAC, a novel caching protocol adaptive to the challenging environment of DTNs. Specifically, we exploit the social community structure to combat the unstable network topology in DTNs. We propose a new centrality metric to evaluate the caching capability of each node within a community, and solutions based on this metric are proposed to determine where to cache. More importantly, we consider the impact of the contact duration limitation on cooperative caching, which has been ignored by the existing works. We prove that the marginal caching benefit that a node can provide diminishes when more data is cached. We derive an adaptive caching bound for each mobile node according to its specific contact patterns with others, to limit the amount of data it caches. In this way, both the storage space and the contact opportunities are better utilized. To mitigate the coupon collector’s problem, network coding techniques are used to further improve the caching efficiency. Extensive trace-driven simulations show that our cooperative caching protocol can significantly improve the performance of data access in DTNs