bluuebunny/crossref_metadata_2025 huggingface dataset:
Is endemic political corruption hampering provision of ART and PMTCT in developing countries?
Authors: Man Wing Young Nicola , Worth Heather , Kelly Angela , Wilson David P , Siba Peter
Published: May 2014

Introduction

Leadership is a key factor in the success of HIV prevention and treatment. Positive HIV‐related outcomes are also affected by funding levels for HIV, health sector resources, disease burden and the socio‐economic environment. Leadership on HIV as well as these other factors are affected by the quality of political governance of the country, which may be an overarching factor that influences the making of effective responses to the HIV epidemic.

Aim

The aim of the study was to investigate the association between quality of political governance, on one hand, and coverage of antiretroviral therapy (ART) and prevention of mother‐to‐child transmission (PMTCT), on the other, in low‐ to middle‐income countries.

Methods

This investigation was carried out through a global review, online data sourcing and statistical analyses. We collected data on health burden and resources, the socio‐economic environment, HIV prevalence, ART and PMTCT coverage and indicators of political governance. Outcome variables were coverage of ART (from 2004) and PMTCT (from 2007) to 2009 as a percentage of persons needing it. Potential predictors of treatment coverage were fitted with a baseline multilevel model for univariable and multivariable analyses.

Results

Countries with higher levels of political voice and accountability, more political stability and better control of corruption have higher levels of ART coverage but not PMTCT coverage. Control of corruption (in standard deviation units) had a strong association with ART (AOR=1.82, p=0.002) and PMTCT (AOR=1.97, p=0.01) coverage. Indicators of economic development were not significant when control of corruption was included in the multivariable regression model. Many countries in all income groups had high ART but not PMTCT coverage (e.g. Mexico, Brazil and Romania in the upper‐middle‐income group; Papua New Guinea and Philippines in the lower‐middle‐income group; and Cambodia, Laos and Comoros in the low‐income group). Very few low‐income countries (notably, Haiti and Kenya) had high PMTCT coverage.

Conclusions

Our research found a significant relationship between quality of political governance and treatment coverage. Measures and policies for improving the quality of political governance should be considered as a part of HIV programme implementation to more effectively improve the welfare of people living with HIV, particularly mothers living with HIV and their babies.
Backscattered energetic neutral atoms from the Moon in the Earth's plasma sheet observed by Chandarayaan‐1/Sub‐keV Atom Reflecting Analyzer instrument
Authors: Harada Yuki , Futaana Yoshifumi , Barabash Stas , Wieser Martin , Wurz Peter , Bhardwaj Anil , Asamura Kazushi , Saito Yoshifumi , Yokota Shoichiro , Tsunakawa Hideo , Machida Shinobu
Published: May 2014

We present the observations of energetic neutral atoms (ENAs) produced at the lunar surface in the Earth's magnetotail. When the Moon was located in the terrestrial plasma sheet, Chandrayaan‐1 Energetic Neutrals Analyzer (CENA) detected hydrogen ENAs from the Moon. Analysis of the data from CENA together with the Solar Wind Monitor (SWIM) onboard Chandrayaan‐1 reveals the characteristic energy of the observed ENA energy spectrum (the e‐folding energy of the distribution function) ∼100 eV and the ENA backscattering ratio (defined as the ratio of upward ENA flux to downward proton flux) <∼0.1. These characteristics are similar to those of the backscattered ENAs in the solar wind, suggesting that CENA detected plasma sheet particles backscattered as ENAs from the lunar surface. The observed ENA backscattering ratio in the plasma sheet exhibits no significant difference in the Southern Hemisphere, where a large and strong magnetized region exists, compared with that in the Northern Hemisphere. This is contrary to the CENA observations in the solar wind, when the backscattering ratio drops by ∼50% in the Southern Hemisphere. Our analysis and test particle simulations suggest that magnetic shielding of the lunar surface in the plasma sheet is less effective than in the solar wind due to the broad velocity distributions of the plasma sheet protons.
Capillary pressure overshoot for unstable wetting fronts is explained by Hoffman's velocity‐dependent contact‐angle relationship
Authors: Baver Christine E. , Parlange J.‐Yves , Stoof Cathelijne R. , DiCarlo David A. , Wallach Rony , Durnford Deanna S. , Steenhuis Tammo S.
Published: May 2014

Pore velocity‐dependent dynamic contact angles provide a mechanism for explaining the formation of fingers/columns in porous media. To study those dynamic contact angles when gravity is present, rectangular capillary tubes were used to facilitate observation of the complete interface without geometric distortion. Results show that the Hoffman (1975) relationship between dynamic contact angle and water velocity applies to gravity‐affected flow fields, and that it (when adjusted for nonzero static contact angles) can be used to model dynamic capillary pressures for unstable wettings fronts in porous media by assuming that (1) pressure at the wetting front is discontinuous, (2) the flow field behind the fingertip is highly heterogeneous, and (3) the front line advances one or a few pores at the time. We demonstrate the utility of the Hoffman relationship for porous media with a published infiltration experiment by calculating the capillary pressure successfully at the unstable wetting front as a function of the flux of water in the finger and the grain size diameter.
On the magmatic record of the Makran arc, southeastern Iran: Insights from zircon U‐Pb geochronology and bulk‐rock geochemistry
Authors: Pang Kwan‐Nang , Chung Sun‐Lin , Zarrinkoub Mohammad Hossein , Chiu Han‐Yi , Li Xian‐Hua
Published: May 2014

Twenty‐one magmatic rocks were analyzed for major and trace elements, and a subset of them for Sr‐Nd isotopes and zircon U‐Pb isotopes, to constrain magma genesis and tectonic evolution of the Makran arc, southeastern Iran. Representative samples from the Bazman and Taftan volcanoes yield zircon U‐Pb ages from ∼0.84 to ∼7.5 Ma, consistent with published ages ranging from the Late Miocene to Late Pleistocene. The Mirabad granitic pluton adjacent to and geochemically similar to the Taftan volcano was dated at ∼19 Ma, indicating that arc magmatism might have started earlier than commonly thought in the Early Miocene. The studied rocks show basaltic to rhyolitic compositions, calc‐alkaline affinity, and an orogenic signature involving enrichments in large ion lithophile elements, light rare earth elements, Th and Pb, and depletions in high field strength elements and P, relative to elements of similar incompatibilities. The trace element ratios in a subset of relatively primitive samples are consistent with derivation from a mantle source that underwent subduction‐related enrichment. The covariations of Sr and Nd isotopic ratios, and of these ratios and MgO and SiO2, are consistent with combined assimilation and fractional crystallization. The process is modeled using covariations of 87Sr/86Sr and Sr concentration in the studied rocks given that Sr behaves as neutral or slightly incompatible. We propose, in light of published and our new data, that the Makran represents a window of continental collision between the India‐Eurasia collision zone to the east and the Arabia‐Eurasia collision zone to the west.
Rhizon sampler alteration of deep ocean sediment interstitial water samples, as indicated by chloride concentration and oxygen and hydrogen isotopes
Authors: Miller Madeline D. , Adkins Jess F. , Hodell David A.
Published: May 2014

Despite their potential to inform past ocean salinity, δ18O, and temperature, high‐resolution depth profiles of interstitial water chloride concentration and hydrogen and oxygen isotopes exist in very few locations. One of the primary limitations to the recovery of these depth profiles is that traditional interstitial water sampling requires 5–10 cm whole rounds of the sediment core, which has the potential to interfere with stratigraphic continuity. The Rhizon sampler, a nondestructive tool developed for terrestrial sediment interstitial water extraction, has been proposed for efficient and nondestructive sampling of ocean sediment pore waters. However, there exists little documentation on the reliability and performance of Rhizon samplers in deep ocean sediments, particularly in regard to their effect on chloride concentration and oxygen and hydrogen isotopic measurements. We perform an intercomparison of chloride concentration and oxygen and hydrogen isotopic composition in samples taken using traditional squeezing versus those taken with Rhizon samplers. We find that samples taken with Rhizons have positive biases in both chloride concentration and stable isotopic ratios relative to those taken by squeezing water from sediments in a hydraulic press. The measured offsets between Rhizon and squeeze samples are consistent with a combination of absorption by and diffusive fractionation through the hydrophilic membrane of the Rhizon sampler. These results suggest caution is needed when using Rhizons for sampling interstitial waters in any research of processes that leave a small signal‐to‐noise ratio in dissolved concentrations or isotope ratios.
The wavelet transform function to analyze interplanetary scintillation observations
Authors: Aguilar‐Rodriguez E. , Rodriguez‐Martinez M. , Romero‐Hernandez E. , Mejia‐Ambriz J. C. , Gonzalez‐Esparza J. A. , Tokumaru M.
Published: May 2014

Interplanetary scintillation (IPS) observations are useful to remotely sense the inner heliosphere. We present a new technique to analyze IPS observations using a wavelet transform (WT) function. This technique allows us to derive, in a straightforward way, a simple method to obtain the scintillation index (m). We tested this WT technique to analyze IPS observations obtained by the Solar‐Terrestrial Environment Laboratory (STEL) radio telescope. The analysis of themindex of the radio source 3C48 detected by STEL over the year 2012 shows the expected decrease with solar elongation reported in previous studies. The WT technique has a great potential for future solar wind studies using IPS observations from contemporary radio telescopes.
Isolating the anthropogenic component of Arctic warming
Authors: Chylek Petr , Hengartner Nicholas , Lesins Glen , Klett James D. , Humlum Ole , Wyatt Marcia , Dubey Manvendra K.
Published: May 2014

Structural equation modeling is used in statistical applications as both confirmatory and exploratory modeling to test models and to suggest the most plausible explanation for a relationship between the independent and the dependent variables. Although structural analysis cannot prove causation, it can suggest the most plausible set of factors that influence the observed variable. We apply structural model analysis to the annual mean Arctic surface air temperature from 1900 to 2012 to find the most effective set of predictors and to isolate the anthropogenic component of the recent Arctic warming by subtracting the effects of natural forcing and variability from the observed temperature. We find that anthropogenic greenhouse gases and aerosols radiative forcing and the Atlantic Multidecadal Oscillation internal mode dominate Arctic temperature variability. Our structural model analysis of observational data suggests that about half of the recent Arctic warming of 0.64 K/decade may have anthropogenic causes.
Strong ionospheric field‐aligned currents for radial interplanetary magnetic fields
Authors: Wang Hui , Lühr Hermann , Shue Jih‐Hong , Frey Harald. U. , Kervalishvili Guram , Huang Tao , Cao Xue , Pi Gilbert , Ridley Aaron J.
Published: May 2014

The present work has investigated the configuration of field‐aligned currents (FACs) during a long period of radial interplanetary magnetic field (IMF) on 19 May 2002 by using high‐resolution and precise vector magnetic field measurements of CHAMP satellite. During the interest period IMF By and Bz are weakly positive and Bx keeps pointing to the Earth for almost 10 h. The geomagnetic indices Dst is about −40 nT and AE about 100 nT on average. The cross polar cap potential calculated from Assimilative Mapping of Ionospheric Electrodynamics and derived from DMSP observations have average values of 10–20 kV. Obvious hemispheric differences are shown in the configurations of FACs on the dayside and nightside. At the south pole FACs diminish in intensity to magnitudes of about 0.1 μA/m2, the plasma convection maintains two‐cell flow pattern, and the thermospheric density is quite low. However, there are obvious activities in the northern cusp region. One pair of FACs with a downward leg toward the pole and upward leg on the equatorward side emerge in the northern cusp region, exhibiting opposite polarity to FACs typical for duskward IMF orientation. An obvious sunward plasma flow channel persists during the whole period. These ionospheric features might be manifestations of an efficient magnetic reconnection process occurring in the northern magnetospheric flanks at high latitude. The enhanced ionospheric current systems might deposit large amount of Joule heating into the thermosphere. The air densities in the cusp region get enhanced and subsequently propagate equatorward on the dayside. Although geomagnetic indices during the radial IMF indicate low‐level activity, the present study demonstrates that there are prevailing energy inputs from the magnetosphere to both the ionosphere and thermosphere in the northern polar cusp region.
Interseismic coupling, seismic potential, and earthquake recurrence on the southern front of the Eastern Alps (NE Italy)
Authors: Cheloni D. , D'Agostino N. , Selvaggi G.
Published: May 2014

Here we use continuous GPS observations to document the geodetic strain accumulation across the South‐Eastern Alps (NE Italy). We estimate the interseismic coupling on the intracontinental collision thrust fault and discuss the seismic potential and earthquake recurrence. We invert the GPS velocities using the back slip approach to simultaneously estimate the relative angular velocity and the degree of interseismic coupling on the thrust fault that separates the Eastern Alps and the Venetian‐Friulian plain. Comparison between the rigid rotation predicted motion and the shortening observed across the area indicates that the South‐Eastern Alpine thrust front absorbs about 70% of the total convergence between the Adria and Eurasia plates. The coupling is computed on a north dipping fault following the continuous external seismogenic thrust front of the South‐Eastern Alps. The modeled thrust fault is currently locked from the surface to a depth of ≈10 km. The transition zone between locked and creeping portions of the fault roughly corresponds with the belt of microseismicity parallel and to the north of the mountain front. The estimated moment deficit rate is 1.3 ± 0.4 × 1017Nm/yr. The comparison between the estimated moment deficit and that released historically by the earthquakes suggests that to account for the moment deficit the following two factors or their combination should be considered: (1) a significant part of the observed interseismic coupling is released aseismically and (2) infrequent “large” events with long return period (> 1000 years) and with magnitudes larger than the value assigned to the largest historical events (Mw≈ 6.7).
Saturated and Multi‐Colored Electroluminescence from Quantum Dots Based Light Emitting Electrochemical Cells
Authors: Qian Gang , Lin Ying , Wantz Guillaume , Davis Andrew R. , Carter Kenneth R. , Watkins James J.
Published: May 2014

Novel light emitting electrochemical cells (LECs) are fabricated using CdSe‐CdS (core‐shell) quantum dots (QDs) of tuned size and emission blended with polyvinylcarbazole (PVK) and the ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIM‐PF6). The performances of cells constructed using sequential device layers of indium tin oxide (ITO), poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS), the QD/PVK/IL active layer, and Al are evaluated. Only color saturated electroluminescence from the QDs is observed, without any other emissions from the polymer host or the electrolyte. Blue, green, and red QD‐LECs are prepared. The maximum brightness (≈1000 cd m‐2) and current efficiency (1.9 cd A‐1) are comparable to polymer LECs and multilayer QD‐LEDs. White‐light QD‐LECs with Commission Internationale d'Eclairage (CIE) coordinates (0.33, 0.33) are prepared by tuning the mass ratio of R:G:B QDs in the active layer and voltage applied. Transparent QD‐LECs fabricated using transparent silver nanowire (AgNW) composites as the cathode yield an average transmittance greater than 88% over the visible range. Flexible devices are demonstrated by replacing the glass substrates with polyethylene terephthalate (PET).
A Symmetrical Fluorous Dendron‐Cyanine Dye‐Conjugated Bimodal Nanoprobe for Quantitative 19F MRI and NIR Fluorescence Bioimaging
Authors: Wang Zhe , Yue Xuyi , Wang Yu , Qian Chunqi , Huang Peng , Lizak Marty , Niu Gang , Wang Fu , Rong Pengfei , Kiesewetter Dale O. , Ma Ying , Chen Xiaoyuan
Published: May 2014

19F MRI and optical imaging are two powerful noninvasive molecular imaging modalities in biomedical applications. 19F MRI has great potential for high resolution in vivo imaging, while fluorescent probes enable ultracontrast cellular/tissue imaging with high accuracy and sensitivity. A bimodal nanoprobe is developed, integrating the merits of 19F MRI and fluorescence imaging into a single synthetic molecule, which is further engineered into nanoprobe, by addressing shortcomings of conventional contrast agents to explore the quantitative 19F MRI and fluorescence imaging and cell tracking. Results show that this bimodal imaging nanoprobe presents high correlation of 19F MR signal and NIR fluorescence intensity in vitro and in vivo. Additionally, this nanoprobe enables quantitative 19F MR analysis, confirmed by a complementary fluorescence analysis. This unique feature can hardly be obtained by traditional 19F MRI contrast agents. It is envisioned that this nanoprobe can hold great potential for quantitative and sensitive multi‐modal molecular imaging.
Superhydrophobic Gated Polyorganosilanes/Halloysite Nanocontainers for Sustained Drug Release
Authors: Fan Ling , Li Bucheng , Wang Qin , Wang Aiqin , Zhang Junping
Published: May 2014

Inspired by the water repellency of the lotus leaf, superhydrophobic gated nanocontainers are fabricated by using halloysite nanotubes (HNTs) as the nanocontainers and polyorganosilanes (POS) as the molecular gates for sustained release of diclofenac sodium (DS). The nanocontainers are prepared by loading DS into the lumen of HNTs, and then modified by co‐condensation of hexadecyltriethoxylsilane and tetraethoxysilane. The nanocontainers are characterized with transmission electron microscopy, energy dispersive X‐ray analysis and FTIR, etc. The wetting behaviors of the nanocontainers and release behaviors of DS are also studied. DS molecules are loaded in the lumen of HNTs and POS is covalently bonded on the surface of HNTs‐DS. Wettability of the nanocontainers is controllable simply by the POS content. The nanocontainers show excellent superhydrophobicity with a water contact angle of 156.9° and a water shedding angle of 3°. The release of DS molecules is controlled by a new way, the air cushion between the superhydrophobic nanocontainers and the phosphate buffer solution (PBS). The DS molecules could only release from the limited place where the nanocontainers contact with PBS when the PBS is in the Cassie‐Baxter state on the surface of the nanocontainers.
Suppressing Twin Formation in Bi2Se3 Thin Films
Authors: Tarakina N. V. , Schreyeck S. , Luysberg M. , Grauer S. , Schumacher C. , Karczewski G. , Brunner K. , Gould C. , Buhmann H. , Dunin‐Borkowski R. E. , Molenkamp L. W.
Published: May 2014

The microstructure of Bi2Se3 topological‐insulator thin films grown by molecular beam epitaxy on InP(111)A and InP(111)B substrates that have different surface roughnesses has been studied in detail using X‐ray diffraction, X‐ray reflectivity, atomic force microscopy and probe‐corrected scanning transmission electron microscopy. The use of a rough Fe‐doped InP(111)B substrate results in complete suppression of twin formation in the Bi2Se3 thin films and a perfect interface between the films and their substrates. The only type of structural defect that persists in the twin‐free films is an antiphase domain boundary, which is associated with variations in substrate height. We also show that the substrate surface termination influences which family of twin domains dominates.
Preparation and properties of novel boric acid modified poly(aryl ether sulfone) membranes
Authors: Wang Yongpeng , Zhang Haibo , Liu Mengzhu , Zhu Ye , Cui Zengduo , Lin Yingjian , Zhu Xuanbo , Jiang Zhenhua
Published: May 2014

In this article, boric acid‐modified poly(aryl ether sulfone) (PES‐B) membranes were prepared by solution blending, solution casting, evaporation, and programmed temperature curing method for the first time. The chemical modification of poly(aryl ether sulfone) was accomplished by the curing of poly(aryl ether sulfone) with pendent phenyl hydroxide (PES‐OH) under the function of boric acid. The reaction mechanisms and the effects of boric acid content were thoroughly investigated. Processing conditions and structures of PES‐B were determined by FT‐IR spectra. It has been found that the B(OH)3/PES composite membranes were completely cured after treatment at 300°C for 4 h. When boric acid content was over 4.7%, PES‐B membranes presented phase separation and full cross‐linking structures. DSC measurements demonstrated that the addition of boric acid had influenced the glass transition temperature of PES‐B, which provided the proof of the appearance of cross‐linking network structure. TGA results confirmed that the thermal stability of the prepared PES‐B composites was improved. Furthermore, the cross‐linked composite membranes exhibited excellent mechanical property and solvent resistance. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40860.
Europium‐containing cholesteric liquid crystalline polymers in the side chain
Authors: Zhao Wen‐Zhi , Cong Yue‐Hua , Zhang Bao‐Yan , Gu Wei‐Min
Published: May 2014

Europium‐containing cholesteric liquid crystalline polymers were graft copolymerized using poly(methylhydrogeno)siloxane, cholesteryl 4‐(allyloxy)benzoate (M1), cholesteryl acrylate (M2), and a europium complexes monomer (M3). The chemical structures of the monomers were characterized by Fourier transform infrared and 1H‐nuclear magnetic resonance. The mesomorphic properties and phase behavior were investigated by differential scanning calorimetry, thermo gravimetric analysis, polarizing optical microscopy, and X‐ray diffraction. With an increase of europium complexes units in the polymers, the glass transition temperature (Tg) did not change significantly; the isotropic temperature (Ti) and mesophase temperature range (ΔT) decreased. All polymers showed typical cholesteric Grandjean textures, which was confirmed by X‐ray diffraction. The temperatures at which 5% weight loss occurred (Td) were greater than 300°C for the polymers. The introduction of europium complexes units did not change the liquid crystalline state of polymer systems; on the contrary, the polymers were enabled with the significant luminescent properties. With Eu3+ ion contents ranging between 0 and 1.5 mol %, luminescent intensity of polymers gradually increased and luminescent lifetimes were longer than 0.45 ms for the polymers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40866.
Annotating for the world: Attitudes toward sharing scholarly annotations
Authors: Hemminger Bradley M. , TerMaat Julia
Published: May 2014

Annotations, in the form of markings and comments on the text, are often part of scholarly work. Digital platforms increasingly allow these annotations to be shared in group and public environments. To explore scholars' current behavior and attitudes toward shared annotations, semistructured interviews with 20 doctoral students were conducted. The findings suggest that sociocognitive processes are integral to scholars' creation and use of shared annotations. However, although scholars clearly support creating and using shared annotations, several sociocognitive hurdles have hampered adoption of scholarly shared annotation systems. This article discusses common themes emerging from the findings and relates them to research on shared annotations.
Big data and its epistemology
Authors: Frické Martin
Published: May 2014

The article considers whether Big Data, in the form of data‐driven science, will enable the discovery, or appraisal, of universal scientific theories, instrumentalist tools, or inductive inferences. It points out, initially, that such aspirations are similar to the now‐discredited inductivist approach to science. On the positive side, Big Data may permit larger sample sizes, cheaper and more extensive testing of theories, and the continuous assessment of theories. On the negative side, data‐driven science encourages passive data collection, as opposed to experimentation and testing, and hornswoggling (“unsound statistical fiddling”). The roles of theory and data in inductive algorithms, statistical modeling, and scientific discoveries are analyzed, and it is argued that theory is needed at every turn. Data‐driven science is a chimera.
Atrazine and Pregnancy Outcomes: A Systematic Review of Epidemiologic Evidence
Authors: Goodman Michael , Mandel Jack S. , DeSesso John M. , Scialli Anthony R.
Published: May 2014

Atrazine (ATR) is a commonly used agricultural herbicide that has been the subject of epidemiologic studies assessing its relation to reproductive health problems. This review evaluates both the consistency and the quality of epidemiologic evidence testing the hypothesis that ATR exposure, at usually encountered levels, is a risk factor for birth defects, small for gestational age birth weight, prematurity, miscarriages, and problems of fetal growth and development. We followed the current methodological guidelines for systematic reviews by using two independent researchers to identify, retrieve, and evaluate the relevant epidemiologic literature on the relation of ATR to various adverse outcomes of birth and pregnancy. Each eligible paper was summarized with respect to its methods and results with particular attention to study design and exposure assessment, which have been cited as the main areas of weakness in ATR research. As a quantitative meta‐analysis was not feasible, the study results were categorized qualitatively as positive, null, or mixed. The literature on ATR and pregnancy‐related health outcomes is growing rapidly, but the quality of the data is poor with most papers using aggregate rather than individual‐level information. Without good quality data, the results are difficult to assess; however, it is worth noting that none of the outcome categories demonstrated consistent positive associations across studies. Considering the poor quality of the data and the lack of robust findings across studies, conclusions about a causal link between ATR and adverse pregnancy outcomes are not warranted.
Multigeneration Reproduction and Male Developmental Toxicity Studies on Atrazine in Rats
Authors: DeSesso John M. , Scialli Anthony R. , White Tacey E. K. , Breckenridge Charles B.
Published: May 2014

BACKGROUND

Reproductive toxicity of Atrazine (ATR) was evaluated in two rat multigenerational studies. Development of male reproductive parameters was evaluated in separate studies after prenatal or postnatal exposure.

METHODS

In multigenerational studies, rats received dietary concentrations of 0, 10, 50, 100 or 500 ppm ATR. In separate studies in female rats, ATR was administered by gavage at 0, 1, 5, 25 or 125 mg/kg/day during pregnancy (GD6–21) or lactation (LD2–21). Plasma testosterone concentration, testicular and epididymal weights, and sperm counts were measured in male offspring on PND70 and 170.

RESULTS

In the multigenerational studies, parental systemic toxicity occurred at 500 ppm (38.7 mg/kg/day), but reproductive endpoints were unaffected. In the prenatal study, maternal toxicity and embryo‐fetal mortality occurred at 125 mg/kg/day. In male offspring, testosterone levels and sperm counts were unaffected, although the percentage of abnormal sperm increased at 125 mg/kg/day (PND 70) and 25 mg/kg/day (PND170). In the postnatal study, maternal toxicity and reduced body weights of male offspring occurred at 125 mg/kg/day. Additionally, reduced testicular (PND70, PND170) and epididymal (PND70) weights and increased numbers of abnormal sperm (PND70, PND170) were seen, but no changes in plasma testosterone or sperm counts.

CONCLUSIONS

Dietary administration of ATR did not affect rat reproduction up to a parentally toxic dose of 38.7 mg/kg/day. Some effects on male reproductive system development occurred after high dose, bolus administration to dams, but doses were much higher than expected under normal use conditions. Thus, oral RfDs for ATR would be protective for reproductive effects
Effects of Ethylene Glycol Monomethyl Ether and Its Metabolite, 2‐Methoxyacetic Acid, on Organogenesis Stage Mouse Limbs In Vitro
Authors: Dayan Caroline , Hales Barbara F.
Published: May 2014

Exposure to ethylene glycol monomethyl ether (EGME), a glycol ether compound found in numerous industrial products, or to its active metabolite, 2‐methoxyacetic acid (2‐MAA), increases the incidence of developmental defects. Using an in vitro limb bud culture system, we tested the hypothesis that the effects of EGME on limb development are mediated by 2‐MAA‐induced alterations in acetylation programming. Murine gestation day 12 embryonic forelimbs were exposed to 3, 10, or 30 mM EGME or 2‐MAA in culture for 6 days to examine effects on limb morphology; limbs were cultured for 1 to 24 hr to monitor effects on the acetylation of histones (H3K9 and H4K12), a nonhistone protein, p53 (p53K379), and markers for cell cycle arrest (p21) and apoptosis (cleaved caspase‐3). EGME had little effect on limb morphology and no significant effects on the acetylation of histones or p53 or on biomarkers for cell cycle arrest or apoptosis. In contrast, 2‐MAA exposure resulted in a significant concentration‐dependent increase in limb abnormalities. 2‐MAA induced the hyperacetylation of histones H3K9Ac and H4K12Ac at all concentrations tested (3, 10, and 30 mM). Exposure to 10 or 30 mM 2‐MAA significantly increased acetylation of p53 at K379, p21 expression, and caspase‐3 cleavage. Thus, 2‐MAA, the proximate metabolite of EGME, disrupts limb development in vitro, modifies acetylation programming, and induces biomarkers of cell cycle arrest and apoptosis
Excessive Retinoic Acid Impaired Proliferation and Differentiation of Human Fetal Palatal Chondrocytes (hFPCs)
Authors: Li Ning , Xu Yusheng , Zhang Huanhuan , Gao Liyun , Li Jue , Wang Yongchao , Gao Zhan , Pan Xinjuan , Liu Xiaozhuan , Li Xing , Yu Zengli
Published: May 2014

Chondrocyte proliferation and differentiation is a fundamental process during hard palatogenesis. Excessive retinoic acid (RA), the biologically most active metabolite of vitamin A, has been reported to adversely affect chondrogenesis. The aim of this study was to investigate the mechanisms underlying RA‐induced chondrocyte differentiation by using human fetal palatal chondrocytes (hFPCs) aging about 9 weeks of amenorrhea. RA treatment inhibited proliferation and induced apoptosis in hFPCs. Alkaline phosphatase activity assay, quantitative alcian blue staining, and real‐time PCR analysis revealed that RA treatment stimulated hFPCs to undergo maturation and terminal differentiation, as demonstrated by decreased chondrogenic markers and increased osteogenic markers. Further studies demonstrated that RA treatment increased Wnt/β‐catenin signaling, as demonstrated by Wnt/β‐catenin target gene expression analysis and a luciferase‐based β‐catenin–activated reporter assay. To address the role of Wnt/β‐catenin signaling, we treated hFPCs with Dickkopf‐related protein 1, an extracellular inhibitor of Wnt/β‐catenin signaling, and the observed all‐trans retinoic acid–mediated increases in nuclear accumulation of β‐catenin, alkaline phosphatase activity, and type I collagen mRNA were attenuated, suggesting that RA modulated Wnt signaling at ligand–receptor level. In summary, excessive all‐trans retinoic acid inhibited proliferation and promoted ossification of hFPCs by upregulation of Wnt/β‐catenin signaling
Size‐Controlled Synthesis of Tetrametallic Ag@CoNiFe Core–Shell Nanoparticles Supported on Graphene: A Highly Efficient Catalyst for the Hydrolytic Dehydrogenation of Amine Boranes
Authors: Yang Lan , Su Jun , Luo Wei , Cheng Gongzhen
Published: May 2014

Tetrametallic core–shell Ag@CoNiFe nanoparticles (NPs) supported on graphene have been synthesized by a facile one‐step in situ procedure for the first time. We tuned the reducing ability of the reductants to control the structure and particle size of the as‐synthesized NPs. The use of weaker reducing agents, such as ammonia borane (AB) and methylamine borane (MeAB), result in the core–shell structure, whereas the stronger reducing agent NaBH4 results in alloy NPs. The as‐synthesized core–shell NPs reduced by MeAB possess a smaller particle size and exhibit a superior catalytic activity compared to the core–shell NPs reduced by AB and alloy NPs reduced by NaBH4 for the hydrolytic dehydrogenation of AB. Moreover, the turnover frequency of the as‐synthesized tetrametallic core–shell NPs is 118.5 mol min−1 molAg−1, which is higher than that of Ag‐based trimetallic, bimetallic core–shell, and alloy counterparts and even higher than that of most reported noble‐metal‐based NPs. Kinetic studies indicate that the catalytic hydrolysis of AB and MeAB by the Ag@CoNiFe/graphene NPs is a first‐order reaction. Furthermore, the as‐prepared NPs exert good catalytic activities and recycle stabilities towards the hydrolysis of AB. Additionally, the as‐prepared NPs display magnetic recyclability, which makes the practical recycling of the NPs more convenient.
Aerobic Oxidation of Alcohols on Au Nanocatalyst: Insight to the Roles of the Ni–Al Layered Double Hydroxides Support
Authors: Wang Jiang , Lang Xianjun , Zhaorigetu Bao , Jia Meilin , Wang Jun , Guo Xiaofang , Zhao Jincai
Published: May 2014

Au nanoparticles (NPs) supported on Ni–Al layered double hydroxides (LDHs) were shown to be efficient heterogeneous catalysts for the highly selective oxidation of alcohols to the corresponding aldehydes or ketones under base‐free or even solvent‐free conditions with O2 as the sole oxidant. The Au NPs can be uniformly distributed on Ni–Al LDHs support, which is beneficial to the catalytic activity. In addition, the weak Brønsted basic property of the support enables the aerobic oxidation of alcohols under base‐free conditions. More importantly, unlike Al2O3, which is inert, Ni–Al–LDHs are redox‐actively involved in prompting the electron transfer to O2 via the Au nanocatalyst because of the presence of NiII. Both of the basic and the redox properties of Ni–Al–LDHs can be tuned by adjusting the ratio of Ni:Al to achieve the best synergistic effects between Au NPs and the supports. The activity of the obtained Au catalysts was found to be structurally associated with the arrangements of NiO6 and AlO6 octahedra in the surface hydroxide layers which were different from the bulk Ni:Al ratio.
Sensitive and Selective Detection of Imidacloprid by Graphene‐Oxide‐Modified Glassy Carbon Electrode
Authors: Lei Wu , Han Zhen , Si Weimeng , Hao Qingli , Zhang Yuehua , Xia Mingzhu , Wang Fengyun
Published: May 2014

Based on the enhancement effect of graphene oxide (GO), a GO‐modified glassy carbon electrode (GO/GCE) is prepared for the fast and sensitive electrochemical detection of the imidacloprid (IMI) insecticide, with high selectivity and stability, for the first time. The electrochemical behavior of imidacloprid on GO/GCE is investigated by using cyclic voltammetry, and graphene oxide is found to have a strong affinity towards IMI. The reduction peak current varies linearly with the concentration of IMI over the 0.8–10 μM range and the limit of detection is 0.36 μM.
A Langevin Canonical Approach to the Dynamics of Chiral Systems: Thermal Averages and Heat Capacity
Authors: Peñate‐Rodríguez Helen C. , Dorta‐Urra Anais , Bargueño Pedro , Rojas‐Lorenzo German , Miret‐Artés Salvador
Published: May 2014

A Langevin canonical framework for a chiral two‐level system coupled to a bath of harmonic oscillators was developed within a coupling scheme different from the well‐known spin‐boson model. Thermal equilibrium values were reached at asymptotic times by solving the corresponding set of nonlinear coupled equations in a Markovian regime. In particular, phase difference thermal values (or, equivalently, the so‐called coherence factor) and heat capacity through energy fluctuations were obtained and are discussed in terms of tunneling rates and asymmetries. Chirality 26:319–325, 2014. © 2014 Wiley Periodicals, Inc.
Hyperglycemia in Patients Referred for Cardiac Catheterization Is Associated With Preexisting Diabetes Rather Than a Stress‐Related Phenomenon: A Prospective Cross‐Sectional Study
Authors: Arbel Yaron , Shmueli Hezzy , Halkin Amir , Berliner Shlomo , Shapira Itzhak , Herz Itzhak , Havakuk Ofer , Shacham Yacov , Rabinovich Itay , Keren Gad , Finkelstein Ariel , Banai Shmuel
Published: May 2014

Background

An increased serum glucose level in patients with acute coronary syndrome (ACS) is associated with adverse clinical outcome. This hyperglycemia has been attributed, at least in part, to acute stress reaction. Our objective was to determine whether hyperglycemia is a stress‐related phenomenon or whether it represents a more sustained and possibly significant background dysglycemia.

Hypothesis

Hyperglycemia in patients undergoing coronary angiography is related to background dysglycemia.

Methods

Blood samples were obtained at the time of cardiac catheterization. Patients with hemoglobin A1c >6.5% were excluded to avoid patients with chronic glucose levels above 135 mg/dL. A logistic regression model was created to assess the influence of different variables on hyperglycemia (glucose levels above 140 mg/dL). We also evaluated the effect of glucose levels above 140 mg/dL on major adverse cardiovascular events (MACEs) up to 36 months.

Results

There were 2554 consecutive patients prospectively recruited. Serum glucose levels above 140 mg/dL was a strong predictor of MACE (hazard ratio: 2.2, 95% confidence interval [CI]: 1.3‐3.6, P = 0.002). Both diabetes mellitus and ACS were associated with hyperglycemia (glucose levels above 140 mg/dL). Nevertheless, the incidence of hyperglycemia was doubled in diabetic patients (odds ratio [OR]: 9.4, 95% CI: 3.9‐22.4, P < 0.001) compared with patients with ACS (OR: 4.6, 95% CI: 2.3‐9.0, P < 0.001). Combining both conditions was associated with a high likelihood of elevated glucose levels (OR: 15.5, 95% CI: 7.4‐32.9, P < 0.001).

Conclusions

Hyperglycemia in patients undergoing cardiac catheterization is a strong predictor of adverse outcome. It is mainly related to background dysglycemia and to a lesser extent to the acute stress accompanying ACS.
DNA Binding Dynamics and Energetics of Cobalt, Nickel, and Copper Metallopeptides
Authors: Galindo‐Murillo Rodrigo , Cheatham Thomas E.
Published: May 2014

We present molecular dynamics (MD) and Quantum Theory of Atoms in Molecules (QTAIM) analysis of the DNA binding properties of three metallopeptides to the Drew–Dickerson dodecamer DNA: CoII‐Gly1‐Gly2‐His, NiII‐Gly1‐Gly2‐His and CuII‐Gly1‐Gly2‐His. Fairly extensive MD simulations were run on each system until a stable binding mode for each ligand was sampled. Clustering analysis was used in an attempt to find representative structures for the most populated clusters sampled during the MD, and a QTAIM analysis was performed. Additionally, MM‐PBSA analysis was performed to obtain approximate binding energies for each complex. The results suggest that stable DNA–metallopeptide complexes are formed with each of the three ligands, and that the most stable interaction is with Co(GGH), then Ni(GGH), and finally Cu(GGH). Bond Critical Points (BCP) information between the minor groove of the DNA and the metallopeptides shows an increase in electronic density between Gly1, the His residues, and the oxygen atoms of the thymine nucleotide. Overall, we present a detailed theoretical study of the specific interactions involved and the binding properties of each complex formed.
Monofunctional Platinum(II) Complexes with Potent Tumor Cell Growth Inhibitory Activity: The Effect of a Hydrogen‐Bond Donor/Acceptor N‐Heterocyclic Ligand
Authors: Margiotta Nicola , Savino Salvatore , Gandin Valentina , Marzano Christine , Natile Giovanni
Published: May 2014

In this paper we investigate the possibility of further increase the role of the N‐donor aromatic base in antitumor Hollis‐type compounds by conferring the possibility to act as a hydrogen‐bond donor/acceptor. Therefore, we synthesized the PtIIcomplexcis‐[PtCl(NH3)2(naph)]NO3(1) containing the 1,8‐naphthyridine (naph) ligand. The naphthyridine ligand is generally monodentate, and the second nitrogen atom can act as H‐bond donor/acceptor depending upon its protonation state. The possibility of forming such an H‐bond could be crucial in the interaction of the drug with DNA or proteins. Apart from the synthesis of the compound, in this study we evaluated its in vitro antitumor activity in a wide panel of tumor cell lines, also including cells selected for their sensitivity/resistance to oxaliplatin, which was compared with that of previously reported complex2([PtI(2,9‐dimethyl‐1,10‐phenanthroline)(1‐methyl‐cytosine)]I) and oxaliplatin and cisplatin as reference compounds. The cytotoxicity data were correlated with the cellular uptake and the DNA platination levels. Finally, the reactivity of1towards guanosine 5′‐monophosphate (5’‐GMP) and glutathione was investigated to provide insights into its mechanism of action.
Insulin‐like growth factor 1 receptor inhibitors: Where do we come from? What are we? Where are we going?
Authors: Chmielowski Bartosz
Published: May 2014

The author comments on results from the phase 2 trial of R1507 in patients with sarcoma in the landscape of the disappointing results from clinical trials with insulin‐like growth factor 1 receptor inhibitors.
Aberrant methylation and decreased expression of the TGF‐β/Smad target gene FBXO32 in esophageal squamous cell carcinoma
Authors: Guo Wei , Zhang Minghui , Shen Supeng , Guo Yanli , Kuang Gang , Yang Zhibin , Dong Zhiming
Published: May 2014

BACKGROUND

F‐box protein 32 (FBXO32) (also known as atrogin‐1), a member of the F‐box protein family, has recently been identified as a transforming growth factor beta (TGF‐β)/Smad target gene involved in regulating cell survival, and it may be transcriptionally silenced by epigenetic mechanisms in some kinds of carcinomas, yet its role in esophageal squamous cell carcinoma (ESCC) has not been defined.

METHODS

The role of FBXO32 in ESCC and the correlation of FBXO32 methylation with a series of pathologic parameters were studied in a large cohort of patients with ESCC.

RESULTS

Decreased messenger RNA (mRNA) expression and protein expression of FBXO32 were observed in esophageal cancer cell lines, and the silencing of FBXO32 could be reversed by treatment with 5‐aza‐2′‐deoxycytidine or trichostatin A in the TE13 cell line. In addition, aberrant methylation of FBXO32 and histone deacetylation was capable of suppressing FBXO32 mRNA and protein expression in TE13 cells. Decreased mRNA and protein expression of FBXO32 was observed in ESCC tumor tissues and was associated with FBXO32 promoter methylation status. A positive correlation between FBXO32 and phosphorylated SMAD family members 2 and 3 expression and Smad4 protein expression also was observed in clinical specimens. FBXO32 methylation status and protein expression were independently associated with survival in patients with ESCC.

CONCLUSIONS

FBXO32 may be a functional tumor suppressor. Its inactivation through promoter methylation could play an important role in ESCC carcinogenesis, and reactivation of the FBXO32 gene may have therapeutic potential and might be used as a prognostic marker for patients with ESCC. Cancer 2014;120:2412–2423. © 2014 American Cancer Society.
Effects of implant neck design on primary stability and overload in a type IV mandibular bone
Authors: Chou I‐Chiang , Lee Shyh‐Yuan , Jiang Cho‐Pei
Published: May 2014

This study investigates the effect of implant neck design on primary stability and overload using 3D finite element analysis. Four commercial dental implants and mandibular segments are created. Various parameters including the osseointegration condition (non‐osseointegration and full osseointegration), force direction (vertical and horizontal), and cortical bone thickness (Tc = 0.3, 0.5, and 1 mm) are considered. The vertical and horizontal forces, 500 N and 250 N, are statically applied at the top of the platform, respectively. Micromotion and von Mises stress are employed to evaluate the risk of osseointegration and bone fatigue before osseointegration condition. After osseointegration, the principal stress is used to analyze the bone overload. Maximal von Mises stress and micromotion of the peri‐implant bone decreased as cortical bone thickness increased. Horizontal force induces stress concentration in the bone around the implant neck easier than that of vertical force, and it may result in crestal bone loss. Thinner cortical bone should avoid dental implantation because it causes a noteworthy larger micromotion and stress concentration in cortical bone in particular Tc less than 0.3 mm. Copyright © 2014 John Wiley & Sons, Ltd.
Aluminum Manganese Oxides with Mixed Crystal Structure: High‐Energy‐Density Cathodes for Rechargeable Sodium Batteries
Authors: Han Dong‐Wook , Ku Jun‐Hwan , Kim Ryoung‐Hee , Yun Dong‐Jin , Lee Seok‐Soo , Doo Seok‐Gwang
Published: May 2014

We report a new discovery for enhancing the energy density of manganese oxide (NaxMnO2) cathode materials for sodium rechargeable batteries by incorporation of aluminum. The Al incorporation results in NaAl0.1Mn0.9O2 with a mixture of tunnel and layered crystal structures. NaAl0.1Mn0.9O2 shows a much higher initial discharge capacity and superior cycling performance compared to pristine Na0.65MnO2. We ascribe this enhancement in performance to the formation of a new orthorhombic layered NaMnO2 phase merged with a small amount of tunnel Na0.44MnO2 phase in NaAl0.1Mn0.9O2, and to improvements in the surface stability of the NaAl0.1Mn0.9O2 particles caused by the formation of AlO bonds on their surfaces. Our findings regarding the phase transformation and structure stabilization induced by incorporation of aluminum, closely related to the structural analogy between orthorhombic Na0.44MnO2 and NaAl0.1Mn0.9O2, suggest a strategy for achieving sodium rechargeable batteries with high energy density and stability.
CVD of Pt(C5H9)2 to Synthesize Highly Dispersed Pt/SBA‐15 Catalysts for Hydrogenation of Chloronitrobenzene
Authors: Jiang Manman , Zhang Mingming , Li Chuang , Williams Christopher T. , Liang Changhai
Published: May 2014

Pt supported on mesoporous silica SBA‐15 materials with various loadings are controllably synthesized by metal‐organic(MO)CVD of Pt(C5H9)2 in a Y‐tube reactor. The precursor, Pt(C5H9)2, is successfully prepared by the reaction of dichloro(1,5‐cyclooctadiene)platinum ((COD)PtCl2) with pent‐4‐en‐1‐ylmagnesium bromide, which is confirmed by proton nuclear magnetic resonance (1H‐NMR). Transmission electron microscopy (TEM) images show that Pt nanoparticles with an average size of 4.6 ± 1.1 nm are dispersed uniformly onto the SBA‐15. The performance of Pt/SBA‐15 for the hydrogenation of o‐chloronitrobenzene (o‐CNB) is tested, and is able to achieve high catalytic activity (97%) and selectivity (72%).