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Objective High prepregnancy body mass index (BMI), excessive gestational weight gain (GWG), and gestational diabetes mellitus (GDM) are associated with the risk of childhood obesity. This study aims to examine the extent to which these effects may be mediated through the placenta. Methods Data included 33,893 mothers and their singleton infants from birth to 7 years old (total 154,590 visits) in the Collaborative Perinatal Project, a U.S. multicenter prospective cohort study from 1959 to 1976. The placentas were weighed after removing cord and membranes. We performed sequential generalized estimating equation-linear models excluding and including placental weight to evaluate its mediation effect. Results In this population, 21.7% of mothers had overweight or obesity, 17.3% had excessive GWG, and 350 (1%) had diagnosed GDM; in addition, 7.2% children had obesity. After adjustment for prepregnancy BMI and other covariates, childhood BMI was 0.23 (95% CI: 0.05, 0.40) kg/m2 higher for children born to mothers with GDM versus those without GDM. Inclusion of placental weight in the model attenuated the association by 52% to 0.11 (95% CI: −0.06, 0.28) and similarly attenuated the associations with childhood BMI for GWG by 25% and maternal prepregnancy BMI by 17%. Conclusions Placental weight partly mediates the effects of prepregnancy BMI, excessive GWG, and GDM on childhood BMI.

A novel LiFePO4 material, in the shape of a nanomesh, has been rationally designed and synthesized based on the low crystal-mismatch strategy. The LiFePO4 nanomesh possesses several advantages in morphology and crystal structure, including a mesoporous structure, its crystal orientation that is along the [010] direction, and a shortened Li-ion diffusion path. These properties are favorable for their application as cathode in Li-ion batteries, as these will accelerate the Li-ion diffusion rate, improve the Li-ion exchange between the LiFePO4 nanomesh and the electrolyte, and reduce the Li-ion capacitive behavior during Li intercalation. So the LiFePO4 nanomesh exhibits a high specific capacity, enhanced rate capability, and strengthened cyclability. The method developed here can also be extended to other similar systems, for instance, LiMnPO4 , LiCoPO4 , and LiNiPO4 , and may find more applications in the designed synthesis of functional materials.

Modification of composites was a general method to improve their tribological behaviors. On the way to explore composites with enhanced tribological behaviors, we have successfully prepared hybrid PTFE/Nomex fabric/phenolic composite filled with multiwalled carbon nanotubes (MWCNTs) or MWCNTs modified by polystyrene (PS) with a grafting to method. The results of pin-on-disc type wear tests indicated tribological behaviors were improved both for hybrid PTFE/Nomex fabric/phenolic composite filled with MWCNTs and MWCNTs-PS, especially for that of filled with MWCNTs-PS. And the probable reason was also discussed based on the characterization results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Hybrid PTFE/Kevlar fabric was surface-modified by air plasma to improve the adhesion to phenolic resin. The tribological properties of fabric composite with or without plasma-treated hybrid PTFE/Kevlar fabric were investigated in detail. Friction and wear tests showed that friction-reducing and antiwear ability of hybrid PTFE/Kevlar fabric composite were remarkably improved after plasma treatment. Scanning electron microscopy and X-ray photoelectron spectroscopy results indicated that the fiber surfaces were etched and the contents of oxygen and nitrogen increased after plasma treatment, which was favorable for improved fiber/resin bonding strength. The enhancement contributed to the improved tribological properties of hybrid PTFE/Kevlar fabric composite after plasma treatment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

In this study, the effects of air-plasma and N2-plasma treatment on the hybrid polytetrafluoroethylene (PTFE)/cotton fabric and a phenolic resin were investigated in detail. The tribological properties of the untreated and plasma-treated hybrid PTFE/cotton fabric/phenolic composites were investigated. The results indicated that air-plasma-treated hybrid PTFE/cotton fabric/phenolic composites exhibited better antiwear and friction reduction properties. The combination of scanning electron microscopy and Fourier transform infrared spectroscopy analysis illustrated that hybrid PTFE/cotton fabric/phenolic composites treated with air-plasma possessed more integrated structure and more functional groups, which plausibly contributed to the better tribological properties of the hybrid PTFE/cotton fabric/phenolic composites treated with air-plasma. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

The friction and wear characteristics of ZnO- or montmorillonite-nanoparticle-filled Kevlar fabric composites with different filler proportions when sliding against stainless steel pins under dry friction conditions were studied, with unfilled Kevlar fabric composites used as references. The worn surface and transfer film of Kevlar fabric composites were then examined with a scanning electron microscope. It was found that ZnO and montmorillonite as fillers could improve the tribological behavior of the Kevlar fabric composites with various applied loads, and the best antiwear property was obtained with the composites containing 5 wt % ZnO or montmorillonite. This indicated that these nanoparticles could prevent the destruction of Kevlar fabric composites during the friction process. The transfer film established by these nanoparticles during the sliding wear of the composites against their metallic counterpart made contributions to reducing the friction coefficient and wear rate of the Kevlar fabric composites measured in the test. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

A chemical grafting method was applied to modify TiO2 nanoparticles through covalently introducing glycidoxypropyltrimethoxy silicane (KH560) followed by polyoxymethylene onto the particles to overcome the disadvantages generated by the agglomeration of nanoparticles. TiO2 nanoparticles unmodified and modified were introduced into hybrid polytetrafluoroethylene (PTFE)/cotton fabric composites. Friction and wear test demonstrated that TiO2 nanoparticles unmodified and modified can significantly increase the wear resistance of hybrid PTFE/cotton fabric composites but cannot reduce the friction coefficient. Fabric composites filled with grafted TiO2 nanoparticles exhibited a lower wear rate due to the disintegration of agglomeration and the improvement of interfacial adhesion between filler/matrix. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers

The friction and wear behavior of Kevlar fabric composites reinforced by PTFE or graphite powders was investigated using a Xuanwu-III friction and wear tester at dry sliding condition, with the unfilled Kevlar fabric composite as a reference. The worn surfaces were analyzed by means of scanning electron microscope, and X-ray photoelectron spectroscopy. It was found that PTFE or graphite as fillers could significantly improve the tribological behavior of the Kevlar fabric composites, and the Kevlar fabric composites filled with 20%, PTFE exhibited the best antiwear and antifriction ability among all evaluated cases. The transfer films established with two lubricants in sliding wear of composites against metallic counterparts made contributions to reducing friction coefficient and wear rate of Kevlar fabric composites. In particular, FeF2 generated in the sliding of Kevlar fabric composites filled with PTFE against counterpart pin improved the bonding strength between the transfer film and counterpart surface, which accounted for the lowest friction coefficient and wear rate of the Kevlar fabric composites filled with PTFE measured in the testing. (C) 2008 Wiley Periodicals, Inc.

Aims: To assess the expression profile of the activated form of signal transducer and activator of transcription (Stat)3 in gestational trophoblastic disease (GTD) and correlate the findings with clinicopathological parameters. Methods and results: By immunohistochemistry, both cytoplasmic and nuclear expression of p-Stat3-Ser 727 was demonstrated in 88 trophoblastic tissues, including placentas and GTD. Nuclear immunoreactivity of p-Stat3-Ser 727 was significantly higher in hydatidi-form mole (HM) (P < 0.001) and choriocarcinoma (P = 0.009) when compared with normal placentas. Placental site trophoblastic tumours (PSTT) and epithelioid trophoblastic tumours (ETT) also demonstrated higher nuclear p-Stat3-Ser 727 expression than their normal trophoblast counterparts. Higher p-Stat3-Ser 727 expression was confirmed in choriocarcinoma cell lines, JEG-3 and JAR, than in a normal trophoblast cell line, with both nuclear and cytoplasmic fractions demonstrated by immunoblotting. Spontaneously regressed HM showed significantly increased nuclear and cytoplasmic p-Stat3-Ser 727 immunoreactivity over those that developed gestational trophoblastic neoplasia (GTN) (P = 0.013, P = 0.039). There was a significant positive and inverse correlation between nuclear p-Stat3-Ser 727 immunoreactivity and apoptotic indices [terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick end labelling and M30 Cyto-Death antibody] (P = 0.001, P < 0.001, Spearman's p test) and Bcl-2 expression (P = 0.034), respectively. Conclusions: p-Stat3-Ser 727 plays a role in the pathogenesis of GTD, probably through the regulation of apoptosis. p-Stat3-Ser 727 immunoreactivity is a potential marker in predicting GTN in HM.

Methods based on high performance liquid chromatography coupled with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) for iodine speciation analysis are described. Experiments were performed relating to iodine species, preservative medium and time. The concentration and pH of the buffer are also discussed in relation to separation efficiency. The developed methods allowed the fast and sensitive determination of iodine species with detection limits of 0.025 μg l−1 (as 1) for both iodide and iodate with < 5% relative standard deviation (RSD) for 50 nmol l−1. Attempts were made to quantify total organo-iodine by size-exclusion chromatography (SEC). By way of example, a number of groundwater samples were analysed by these methods, revealing that iodide is the main iodine species in the sampled waters, but that high concentrations of organo-iodine compounds were observed in some samples as well. In summary, the total concentration and the dominant species of iodine in aquatic freshwater environments is easily and accurately measured using this new method. On presente des methodes utilisant la chromatographie liquide de haute performance associee a la spectrometrie de masse a source a plasma induit (HPLC-ICP-MS) pour l'analyse de speciation de l'iode. Les experiences ont ete menees en fonction des especes de l'iode, du milieu et du temps. Les concentrations et pH de la solution tampon sont aussi discutes en relation avec l'efficacite de la separation. Les methodes developpees permettent une determination rapide et sensible des especes de l'iode avec des limites de detection de 0.025 μg l−1 (exprimee sous forme 1) pour les iodures et les iodates, avec une deviation standard relative (RSD) < 5% pour 50 nmol l−1. Les tests ont ete pratiques en vue de quantifier les composes organo-iodes totaux en utilisant la chromatographie d'exclusion de taille (SEC). A titre d'exemple on a analyse avec ces methodes un certain nombre d'eaux souterraines ou l'espece iodee majoritaire se releve etre l'iode elementaire, mais en association dans certains echantillons avec d'importantes concentrations de composes organo-iodes. En resume la determination de la concentration totale et des especes iodees dominantes dans les environnements aquatiques naturels peut etre effectuee facilement et tres justement par ces nouvelles methodes.

A novel method of polymer monolith microextraction (PMME) using poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith combined with electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOF MS) was developed for the rapid and sensitive determination of beta-agonists in pork samples. The conditions of PMME were optimized for the improvement of extraction efficiency and reduction of the matrix interferences from pork. Under the optimal condition, the eluate solution allowed direct analysis by mass spectrometry. In the positive ion mode and in the multiple reaction monitoring (MRM) mode, the limits of detection (LODs) for beta-agonists were found to be 0.08 ng/g (clenbuterol, CLB), 0.18 ng/g (salbutamol, SBTM) and 0.26 ng/g (terbutaline, TBTL) in pork, respectively, with good inter- and intra-day precisions (2-10% for CLB, 11-23% for SBTM and 4-16% for TBTL). The proposed PMME/ESI-QTOF MS method was successfully applied to the determination of beta-agonist residues in thirteen real samples, and the positive samples were confirmed according to the identification points (IPs) system defined by Commission Decision 2002/657/EC. To investigate the matrix effect, the proposed method was compared with PMME-HPLC/ESI-QTOF MS and the slight decrease in sensitivity of PMME/ESI-QTOF MS was ascribed to the inter-analyte ion suppression.

6-Aminoquinolines are available as potential intermediates in drug design using p-chloroaniline as an optimal oxidant in the Skraup—Doebner—von Miller reaction.

Condensation of the zinc salt, formed in nearly quantitative manner, with indoline bases (I) in the presence of cyclic amines affords the title compounds in moderate to good yields.

Rechargeable batteries have attracted increasing attention as power technologies for emerging electric vehicles and grid energy storage, which are expected to mitigate the environmental pollution caused by the use of fossil fuels. Although graphite/lithium transition-metal-oxides (LiCoO 2 , LiNiO 2 , and LiMn 2 O 4 , etc.) and lithium-ion batteries have been the dominant power sources for portable electronics and are used in hybrid electric vehicles, the limited ore resources of these materials make durative rising price. Most crucially, the limitations of potential energy density of these metal-oxide cathode materials are a main restriction in terms of large-scale applications of batteries, particularly in electric vehicles and hybrid electric vehicles. [ 1,2 ] Therefore, it has become urgent to search for alternative energy-storage systems that could complement the existing lithium-ion batteries and that simultaneously have high energy density and long cycle life, in addition to safety and low cost. Alternatively, sodium-sulfur (Na-S) batteries offer low cost, high capacity and high safety, showing great promissing for grid-scale applications. [ 2 ] Both Na and S are abundant and nontoxic elementals on the earth, providing larger availability and lower material cost over the conventional lithium-ion batteries.