bluuebunny/crossref_metadata_2025 huggingface dataset:
Relative effects of geographically isolated wetlands on streamflow: a watershed‐scale analysis
Authors: Golden Heather E. , Sander Heather A. , Lane Charles R. , Zhao Chang , Price Katie , D'Amico Ellen , Christensen Jay R.
Published: January 2015

Geographically isolated wetlands (GIWs) are characterized as ‘isolated’ because they are embedded by uplands, though they potentially exhibit a gradient of hydrologic, biological, or chemical connections to other surface waters. In fact, recent field studies have begun to elucidate that GIWs exhibit varying degrees of hydrologic connectivity. In this study, we examine the influence of GIWs on streamflow, a potential indicator of GIW hydrologic connectivity with surface waters. We assess annual and seasonal spatially based statistical relationships between GIW characteristics (e.g. volume and extent) and streamflow across a dense network of subbasins using a hybrid modeling approach. Our method involves the Spatial Stream Network (SSN) model, which considers spatial autocorrelation of model covariates explicitly, and the Soil and Water Assessment Tool (SWAT), which predicts streamflow across a network of 579 subbasins in the lower Neuse River Basin, North Carolina, USA. Our study results suggest that GIWs, to some extent, influence streamflow. The further GIWs are from a stream, the greater their capacity to increase streamflow due to the physiographic setting, hypothesized transit times, and sequencing of watershed hydrologic connectivity in the study area. However, as the combined extent of GIWs and non‐GIWs increases in subbasins, seasonal and annual streamflow decreases. Results also suggest that other landscape indicators of watershed‐scale hydrology can, in aggregate with GIWs and non‐GIWs, explain variations in seasonal and annual simulated streamflow. Our study findings begin to elucidate the aggregate influence of GIWs on streamflow, providing insights for future decision‐making on GIW protection and management. Copyright © 2015 John Wiley & Sons, Ltd.
Tumor‐induced CD11b+ Gr‐1+ myeloid‐derived suppressor cells exacerbate immune‐mediated hepatitis in mice in a CD40‐dependent manner
Authors: Kapanadze Tamar , Medina‐Echeverz José , Gamrekelashvili Jaba , Weiss Jonathan M. , Wiltrout Robert H. , Kapoor Veena , Hawk Nga , Terabe Masaki , Berzofsky Jay A. , Manns Michael P. , Wang Ena , Marincola Francesco M. , Korangy Firouzeh , Greten Tim F.
Published: January 2015

Immunosuppressive CD11b+Gr‐1+ myeloid‐derived suppressor cells (MDSCs) accumulate in the livers of tumor‐bearing (TB) mice. We studied hepatic MDSCs in two murine models of immune‐mediated hepatitis. Unexpectedly, treatment of TB mice with Concanavalin A (Con A) or α‐galactosylceramide resulted in increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum levels in comparison to tumor‐free mice. Adoptive transfer of hepatic MDSCs into naïve mice exacerbated Con A induced liver damage. Hepatic CD11b+Gr‐1+ cells revealed a polarized proinflammatory gene signature after Con A treatment. An IFN‐γ‐dependent upregulation of CD40 on hepatic CD11b+Gr‐1+ cells along with an upregulation of CD80, CD86, and CD1d after Con A treatment was observed. Con A treatment resulted in a loss of suppressor function by tumor‐induced CD11b+Gr‐1+ MDSCs as well as enhanced reactive oxygen species (ROS)‐mediated hepatotoxicity. CD40 knockdown in hepatic MDSCs led to increased arginase activity upon Con A treatment and lower ALT/AST serum levels. Finally, blockade of arginase activity in Cd40−/− tumor‐induced myeloid cells resulted in exacerbation of hepatitis and increased ROS production in vivo. Our findings indicate that in a setting of acute hepatitis, tumor‐induced hepatic MDSCs act as proinflammatory immune effector cells capable of killing hepatocytes in a CD40‐dependent manner.
Iodine‐Catalyzed Oxidative Amination of Sodium Sulfinates: A Convenient Approach to the Synthesis of Sulfonamides under Mild Conditions
Authors: Buathongjan Chonchanok , Beukeaw Danupat , Yotphan Sirilata
Published: January 2015

The iodine‐catalyzed oxidative amination of sodium sulfinates in the presence of sodium percarbonate as the oxidant has been developed. The reaction shows good substrate scope and tolerates a wide range of functionalities in both amine and sodium sulfinate substrates. Aliphatic amines, heteroaromatic amines and hydrochloride salts of amines can be employed as the amine sources in this transformation. Mechanistic studies indicated that a radical pathway might be involved in the reaction process. This transition‐metal‐free protocol offers an alternative and convenient approach for a preparation of a series of sulfonamides in moderate to good yields under mild conditions.
Copper‐Catalyzed Direct Amination of 1,2,3‐Triazole N‐Oxides by C–H Activation and C–N Coupling
Authors: Zhu Jiayi , Kong Yubo , Lin Feng , Wang Baoshuang , Chen Zhengwang , Liu Liangxian
Published: January 2015

An efficient approach for the synthesis of 4‐amino‐2‐aryl‐1,2,3‐triazole derivatives has been developed through the copper‐catalyzed direct C–H amination of 2‐aryl‐1,2,3‐triazole N‐oxides under mild reaction conditions. Various amines, including primary and secondary aliphatic and aromatic amines, can be employed as effective coupling partners. The general performance of our method was also demonstrated by the oxidative amination of thiazole and imidazole N‐oxides.
Integrated assessment of wastewater treatment plant effluent estrogenicity in the Upper Murray River, Australia, using the native Murray rainbowfish (Melanotaenia fluviatilis)
Authors: Vajda Alan M. , Kumar Anupama , Woods Marianne , Williams Mike , Doan Hai , Tolsher Peter , Kookana Rai S. , Barber Larry B.
Published: January 2015

The contamination of major continental river systems by endocrine-active chemicals (EACs) derived from the discharge of wastewater treatment plant (WWTP) effluents can affect human and ecosystem health. As part of a long-term effort to develop a native fish model organism for assessment of endocrine disruption in Australia's largest watershed, the Murray-Darling River Basin, the present study evaluated endocrine disruption in adult males of the native Australian Murray rainbowfish (Melanotaenia fluviatilis) exposed to effluent from an activated sludge WWTP and water from the Murray River during a 28-d, continuous-flow, on-site experiment. Analysis of the WWTP effluent and river water detected estrone and 17β-estradiol at concentrations up to approximately 25 ng L−1. Anti-estrogenicity of effluent samples was detected in vitro using yeast-based bioassays (yeast estrogen screen) throughout the experiment, but estrogenicity was limited to the first week of the experiment. Histological evaluation of the testes indicated significant suppression of spermatogenesis by WWTP effluent after 28 d of exposure. Plasma vitellogenin concentrations and expression of vitellogenin messenger RNA in liver were not significantly affected by exposure to WWTP effluent. The combination of low contaminant concentrations in the WWTP effluent, limited endocrine disrupting effects in the Murray rainbowfish, and high in-stream dilution factors (>99%) suggest minimal endocrine disruption impacts on native Australian fish in the Murray River downstream from the WWTP outfall. Environ Toxicol Chem 2015;34:1078–1087. © 2015 SETAC
Mixture toxicity of nickel and zinc to Daphnia magna is noninteractive at low effect sizes but becomes synergistic at high effect sizes
Authors: Nys Charlotte , Asselman Jana , Hochmuth Jennifer D. , Janssen Colin R. , Blust Ronny , Smolders Erik , De Schamphelaere Karel A.C.
Published: January 2015

To incorporate metal mixture toxicity effects into risk-assessment procedures, more information is needed about combined and interactive effects of metal mixtures during chronic exposure. The authors investigated the toxicity of binary Ni–Zn mixtures in 2 independent full-factorial experiments using standard chronic (21-d) Daphnia magna reproduction toxicity tests. Global statistical analysis (i.e., when considering all investigated mixture treatments simultaneously) showed noninteractive effects according to the concentration addition model and significant synergistic effects according to the independent action model. However, treatment-specific statistical analysis revealed that both occurrence and type of interactive effect were dependent on the effect size at which Ni and Zn were combined in the mixture. Only noninteractive or weakly antagonistic effects occurred in mixture treatments in which each of the individual metals produced only weak adverse effects on its own (i.e., ≤20% reduction of reproductive performance). On the other side of the spectrum, synergistic mixture effects occurred in all mixture treatments where both metals already caused a  > 20% (for independent action) and a  > 40% (for concentration addition) effect on reproduction on their own. Because low effect sizes are the most relevant in most regulatory frameworks, the authors' data suggest that the concentration addition and independent action mixture toxicity models can both serve as conservative models for predicting effects of Ni–Zn mixtures. The present study highlights the importance of investigating metal mixture toxicity at low effect sizes and warns against extrapolating conclusions about metal mixture interactions from high to low effect sizes. Environ Toxicol Chem 2015;34:1091–1102. © 2015 SETAC
All‐oral 12‐week treatment with daclatasvir plus sofosbuvir in patients with hepatitis C virus genotype 3 infection: ALLY‐3 phase III study
Authors: Nelson David R. , Cooper James N. , Lalezari Jacob P. , Lawitz Eric , Pockros Paul J. , Gitlin Norman , Freilich Bradley F. , Younes Ziad H. , Harlan William , Ghalib Reem , Oguchi Godson , Thuluvath Paul J. , Ortiz‐Lasanta Grisell , Rabinovitz Mordechai , Bernstein David , Bennett Michael , Hawkins Trevor , Ravendhran Natarajan , Sheikh Aasim M. , Varunok Peter , Kowdley Kris V. , Hennicken Delphine , McPhee Fiona , Rana Khurram , Hughes Eric A. ,   on behalf of the ALLY‐3 Study Team
Published: January 2015

Treatment options for patients with hepatitis C virus (HCV) genotype 3 infection are limited, with the currently approved all‐oral regimens requiring 24‐week treatment and the addition of ribavirin (RBV). This phase III study (ALLY‐3; ClinicalTrials.gov: NCT02032901) evaluated the 12‐week regimen of daclatasvir (DCV; pangenotypic nonstructural protein [NS]5A inhibitor) plus sofosbuvir (SOF; pangenotypic NS5B inhibitor) in patients infected with genotype 3. Patients were either treatment naïve (n = 101) or treatment experienced (n = 51) and received DCV 60 mg plus SOF 400 mg once‐daily for 12 weeks. Coprimary endpoints were the proportions of treatment‐naïve and treatment‐experienced patients achieving a sustained virological response (SVR) at post‐treatment week 12 (SVR12). SVR12 rates were 90% (91 of 101) and 86% (44 of 51) in treatment‐naïve and treatment‐experienced patients, respectively; no virological breakthrough was observed, and ≥99% of patients had a virological response (VR) at the end of treatment. SVR12 rates were higher in patients without cirrhosis (96%; 105 of 109) than in those with cirrhosis (63%; 20 of 32). Five of seven patients who previously failed treatment with an SOF‐containing regimen and 2 of 2 who previously failed treatment with an alisporivir‐containing regimen achieved SVR12. Baseline characteristics, including gender, age, HCV‐RNA levels, and interleukin‐28B genotype, did not impact virological outcome. DCV plus SOF was well tolerated; there were no adverse events (AEs) leading to discontinuation and only 1 serious AE on‐treatment, which was unrelated to study medications. The few treatment‐emergent grade 3/4 laboratory abnormalities that were observed were transient. Conclusion: A 12‐week regimen of DCV plus SOF achieved SVR12 in 96% of patients with genotype 3 infection without cirrhosis and was well tolerated. Additional evaluation to optimize efficacy in genotype 3–infected patients with cirrhosis is underway. (Hepatology 2015;61:1127–1135)
Electrode Performances of Amorphous Molybdenum Oxides of Different Molybdenum Valence for Lithium‐ion Batteries
Authors: Jang Jihyun , Kim Sang‐Mo , Kim Youngjin , Park Kern H. , Ku Jun H. , Ryu Ji Heon , Oh Seung M.
Published: January 2015

Amorphous molybdenum oxides are prepared by a reduction of Mo6+ aqueous solution with KBH4. Two molybdenum oxides that differ in the average Mo valence are obtained by changing the solution pH, and their electrode performance is compared with each other. The X‐ray absorption spectroscopy and thermogravimetric analysis illustrate that the sample prepared at the higher pH (4.0) shows an Mo valence of +5.5, which is close to that for MoO3, whereas the Mo valence (+4.4) for the other sample, prepared at the lower pH (0.8), is close to that for MoO2. The latter electrode outperforms the former with respect to cycle retention. The former electrode is lithiated by a conversion reaction, which is the case for MoO3. This electrode exhibits a larger initial capacity, but poorer cycle performance, due to massive volume change and repeated metal‐oxygen bond breaking/formation with cycling. The other electrode, the Mo valence, which is +4.4, is lithiated by an addition reaction, in which Li+ ions are stored in structural defects, such as vacancies and void spaces. The superior cycle performance of this electrode can be ascribed to the absence of massive volume change and bond breaking/formation.
Lewis Pair Polymerization of Acrylic Monomers by N‐Heterocyclic Carbenes and B(C6F5)3
Authors: Chen Jiawei , Chen Eugene Y.‐X.
Published: January 2015

This work has uncovered the first highly active and efficient Lewis pair polymerization (LPP) system based on N‐heterocyclic carbene (NHC)/B(C6F5)3 pairs for converting acrylic monomers into medium‐ to high‐molecular weight polymers. The study has systematically examined steric and electronic effects of three 1,3‐dialkyl(Me, iPr, tBu)imidazol‐2‐ylidene NHCs on the LPP of three classes of acrylic monomers, including linear methyl methacrylate (MMA), cyclic biorenewable γ‐methyl‐α‐methylene‐γ‐butyrolactone (γMMBL), and difunctional allyl methacrylate (AMA). For MMA polymerization, IiPr is not only the most active (∼3× and ∼120× more active than IMe and ItBu, respectively), but also the most effective NHC, especially under low NHC loading conditions. Kinetic results are consistent with a bimolecular, activated monomer propagation mechanism. In the case of the more reactive γMMBL, the polymerization by NHC/B(C6F5)3 in CH2Cl2 is extremely rapid, with all three NHCs achieving quantitative monomer conversion in 1 min and thus reaching a high turnover frequency of≥48,000 h−1. The molecular weight (MW) of PγMMBL can be tuned by adjusting the [γMMBL]/[NHC] ratio, and thus high MW polymers with relatively narrow MW distributions can be readily synthesized (e.g., from Mn=1.41×105 g mol−1, Đ=1.08 to Mn=4.89×105 g mol−1, Đ=1.20). The LPP by NHC/B(C6F5)3 is completely chemoselective, as demonstrated by the polymerization of AMA, which selectively polymerizes the conjugated vinyl group while leaving the non‐conjugated vinyl group in the allyl moiety intact, thanks to its activated monomer propagation mechanism. The resulting PAMA is syndiotactic (rr=83 %), uncross‐linked, and soluble in common solvents, thus suitable for further functionalization. This quantitatively chemoselective polymerization by NHC/B(C6F5)3 should provide a facile, yet powerful, approach to functional acrylic polymers.
Quantitative evaluation of the pulmonary microdistribution of TiO2 nanoparticles using X‐ray fluorescence microscopy after intratracheal administration with a microsprayer in rats
Authors: Zhang Guihua , Shinohara Naohide , Kano Hirokazu , Senoh Hideki , Suzuki Masaaki , Sasaki Takeshi , Fukushima Shoji , Gamo Masashi
Published: January 2015

The unevenness of pulmonary nanoparticle (NP) distribution, which hinders the establishment of an absolute dose–response relationship, has been described as one of the limitations of intratracheal administration techniques for toxicological assessment of inhaled NPs. Quantification of the NP microdistribution would facilitate the establishment of a concentration–response relationship in localized regions of the lung; however, such quantitative methods have not been reported. Here, we established a quantitative method for evaluating pulmonary TiO2 NP microdistribution in rats using X‐ray fluorescence microscopy. Ti intensity in lung sections from rats intratracheally administered 10 mg kg–1 TiO2 NPs with a microsprayer was measured using X‐ray fluorescence with a 100 µm beam size. Ti reference samples were prepared by dropping different concentrations of Ti solutions on glass slide or lung sections of untreated rat. Ti intensity increased linearly with Ti content in the reference samples on both substrates. The detection limit of TiO2 was estimated to be 6.3 ng mm–2. The reproducibility was confirmed for measurements done in the short‐ (2 weeks) and long‐term (6 months). The quantitative results of TiO2 NP microdistribution suggested that more TiO2 NPs were distributed in the right caudal and accessory lobes, which are located downstream of the administration direction of the NP suspension, and the lower portion of each lobe. The detection rates of TiO2 NPs were 16.6–25.0%, 5.19–15.6%, 28.6–39.2%, 21.4–38.7% and 10.6–23.2% for lung sections from the right cranial, middle, caudal, accessory and left lobes, respectively. Copyright © 2015 John Wiley & Sons, Ltd.
Effects of homocysteine on mesenchymal cell proliferation and differentiation during chondrogenesis on limb development
Authors: Bourckhardt Gilian Fernando , Cecchini Manuela Sozo , Ammar Dib , Kobus‐Bianchini Karoline , Müller Yara Maria Rauh , Nazari Evelise Maria
Published: January 2015

High levels of homocysteine (Hcy) are related to an increased risk of the occurrence of congenital anomalies, including limb defects. However, few evaluations about how toxic levels of Hcy affect limb development have been reported. We investigated whether Hcy can affect the cell cycle proteins and proteins involved in mesenchymal cell differentiation during limb development, in a chicken embryo model. Embryos were treated with 20 µmol d‐l Hcy/50 µl saline at embryonic day 2 and analyzed at embryonic day 6. Untreated control embryos received exclusively 50 µl saline solution. To identify cells in proliferation and cell cycle proteins, as well as Pax1/9 and Sox9 proteins, we performed immunolocalization and flow cytometry analyses using the antibodies anti‐phosphohistone H3, anti‐p53, anti‐p21, anti‐proliferating cell nuclear antigen, anti‐Pax1, anti‐Pax9 and anti‐Sox9. No significant differences in cell proliferation were observed between Hcy‐treated and untreated embryos. We observed a decrease of the proliferating cell nuclear antigen and p21 proteins, both involved in the G1 phase of cell cycle progression. On the other hand, in mesenchymal cells of the limbs, Hcy induces an increase of p53 protein, which can be activated by DNA damage. In cell differentiation, Hcy induced an increase mainly of Pax9 and Sox9 proteins. Our data indicate that the treatment with Hcy changes the mesenchymal cell dynamics during limb development, but does not change the morphology of the cartilage molds. These findings provide information to understand better the cellular basis of the toxicity of Hcy on chondrogenesis during limb development. Copyright © 2015 John Wiley & Sons, Ltd.
Design optimization of a radial functionally graded dental implant
Authors: Ichim Paul I. , Hu Xiaozhi , Bazen Jennifer J. , Yi Wei
Published: January 2015

In this work, we use FEA to test the hypothesis that a low‐modulus coating of a cylindrical zirconia dental implant would reduce the stresses in the peri‐implant bone and we use design optimization and the rule of mixture to estimate the elastic modulus and the porosity of the coating that provides optimal stress shielding. We show that a low‐modulus coating of a dental implant significantly reduces the maximum stresses in the peri‐implant bone without affecting the average stresses thus creating a potentially favorable biomechanical environment. Our results suggest that a resilient coating is capable of reducing the maximum compressive and tensile stresses in the peri‐implant bone by up to 50% and the average stresses in the peri‐implant bone by up to 15%. We further show that a transitional gradient between the high‐modulus core and the low‐modulus coating is not necessary and for a considered zirconia/HA composite the optimal thickness of the coating is 100 µ with its optimal elastic at the lowest value considered of 45 GPa. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 58–66, 2016.
Synthesis of 2‐Phenylquinoline and its Derivatives by Multicomponent Reaction of Aniline, Benzylamine, Alcohols, and CCl4 Catalyzed by FeCl3·6H2O
Authors: Khusnutdinov Ravil , Bayguzina Alfiya , Aminov Rishat , Dzhemilev Usein
Published: January 2015

2‐Phenylquinolines, 2‐phenyl‐3‐methyl‐quinolines, and 2‐phenyl‐3‐ethylquinolines were synthesized in high yields (78–90%) by the reaction of aniline, benzylamine, aliphatic alcohols (ethanol, n‐propanol, n‐butanol), and CCl4 catalyzed by FeCl3·6H2O in tetrachloromethane.
Intracerebroventricular oxytocin administration in rats enhances object recognition and increases expression of neurotrophins, microtubule‐associated protein 2, and synapsinI
Authors: Havranek Tomas , Zatkova Martina , Lestanova Zuzana , Bacova Zuzana , Mravec Boris , Hodosy Julius , Strbak Vladimir , Bakos Jan
Published: January 2015

Brain oxytocin regulates a variety of social and affiliative behaviors and affects also learning and memory. However, mechanisms of its action at the level of neuronal circuits are not fully understood. The present study tests the hypothesis that molecular factors required for memory formation and synaptic plasticity, including brain‐derived neurotrophic factor, neural growth factor, nestin, microtubule‐associated protein 2 (MAP2), and synapsin I, are enhanced by central administration of oxytocin. We also investigated whether oxytocin enhances object recognition and acts as anxiolytic agent. Therefore, male Wistar rats were infused continuously with oxytocin (20 ng/µl) via an osmotic minipump into the lateral cerebral ventricle for 7 days; controls were infused with vehicle. The object recognition test, open field test, and elevated plus maze test were performed on the sixth, seventh, and eighth days from starting the infusion. No significant effects of oxytocin on anxious‐like behavior were observed. The object recognition test showed that oxytocin‐treated rats significantly preferred unknown objects. Oxytocin treatment significantly increased gene expression and protein levels of neurotrophins, MAP2, and synapsin I in the hippocampus. No changes were observed in nestin expression. Our results provide the first direct evidence implicating oxytocin as a regulator of brain plasticity at the level of changes of neuronal growth factors, cytoskeletal proteins, and behavior. The data support assumption that oxytocin is important for short‐term hippocampus‐dependent memory. © 2015 Wiley Periodicals, Inc.
Simultaneous synthesis of treatment effects and mapping to a common scale: an alternative to standardisation
Authors: Ades A. E. , Lu Guobing , Dias Sofia , Mayo‐Wilson Evan , Kounali Daphne
Published: January 2015

Objective

Trials often may report several similar outcomes measured on different test instruments. We explored a method for synthesising treatment effect information both within and between trials and for reporting treatment effects on a common scale as an alternative to standardisation

Study design

We applied a procedure that simultaneously estimates a pooled treatment effect and the “mapping” ratios between the treatment effects on test instruments in a connected network. Standardised and non‐standardised treatment effects were compared. The methods were illustrated in a dataset of 22 trials of selective serotonin reuptake inhibitors against placebo for social anxiety disorder, each reporting treatment effects on between one and six of a total nine test instruments.

Results

Ratios of treatment effects on different test instruments varied from trial to trial, with a coefficient of variation of 18% (95% credible interval 11–29%). Standardised effect models fitted the data less well, and standardised treatment effects were estimated with less relative precision than non‐standardised effects and with greater relative heterogeneity.

Conclusion

Simultaneous synthesis of treatment effects and mapping to a common scale make fewer assumptions than standardising by dividing effects by the sample standard deviation, allow results to be reported on a common scale, and deliver estimates with superior relative precision. © 2015 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd.
Impact of polyphenolic components from mulberry on apoptosis of vascular smooth muscle cells
Authors: Chan Kuei‐Chuan , Ho Hsieh‐Hsun , Lin Ming‐Cheng , Huang Chien‐Ning , Huang Hui‐Pei , Wang Chau‐Jong
Published: January 2015

BACKGROUND

Previous studies have shown that mulberry polyphenolic compounds have an anti‐atherosclerotic effect in rabbits. Apoptosis of vascular smooth muscle cells (VSMCs) is the key determinant of the number of VSMCs in remodeling. To examine the effect of mulberry polyphenol extracts (MPEs) on the apoptosis of VSMCs and thus the prevention of atherosclerosis, this study investigated the ability of MPEs to induce apoptosis in vitro and the underlying mechanism.

RESULTS

It was found that MPEs initially activated JNK/p38 and p53, which in turn activated both Fas‐ligand and mitochondrial pathways, thereby causing mitochondrial translocation of Bax and a reduction in Bcl‐2. This then triggered the cleavage of procaspases, finally resulting in apoptosis of VSMCs.

CONCLUSION

This study shows that MPEs may suppress atherosclerosis through stimulating apoptosis of VSMCs via activating JNK/p38 and p53 signaling. © 2015 Society of Chemical Industry
In Vitro Platelet Adhesion of PNaAMPS/PAAm and PNaAMPS/PDMAAm Double‐Network Hydrogels
Authors: Zheng Wen Jiang , Liu Zhen Qi , Xu Feng , Gao Jie , Chen Yong Mei , Gong Jian Ping , Osada Yoshihito
Published: January 2015

Nowadays, tough double‐network (DN) hydrogels have attracted great attention owing to their excellent mechanical properties and good biocompatibility, which give them the potential to be used as blood‐contacting soft tissue prostheses and medical devices. However, the study of platelet adhesion behavior on the surface of DN hydrogels has not been reported yet. In this work, the human platelet adhesion on the surface of poly (sodium 2‐acrylamido‐2‐methyl‐propanesulfonate) PNaAMPS/poly acrylamide (PAAm) and PNaAMPS/poly (N,N′‐dimethylacrylamide) (PDMAAm) DN hydrogels is investigated under static conditions in vitro. The numbers of adherent platelets on PNaAMPS/PAAm and PNaAMPS/PDMAAm hydrogels are 16 ± 7 and 9 ± 8 cells per 104 μm2, respectively, which are far less than 297 ± 41 cells per 104 μm2 on polyethylene terephthalate (PET) and 187 ± 26 cells per 104 μm2 on negatively charged PNaAMPS (4 mol%) hydrogel. The results indicate the excellent antiplatelet performance of DN hydrogels. Moreover, the platelet adhesion mechanism is also discussed. The platelet adhesion is affected by the chemical component, zeta potential, and serum proteins adsorption of the hydrogel.

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Realizations of rotations on an indecomposable compact monothetic group
Authors: Maier Daniel
Published: January 2015

By the classical Halmos‐von Neumann theorem, each compact monothetic group corresponds to an ergodic dynamical system with discrete spectrum. For such groups we prove two results. We first construct a compact monothetic group which does not split into a direct product of a connected and a totally disconnected compact monothetic group. Then we present a measure preserving dynamical system on the unit square being isomorphic to a rotation on this indecomposable group.
Spectroscopic separation of 13C NMR spectra of complex isomeric mixtures by the CSSF‐TOCSY‐INEPT experiment
Authors: Yang Lu , Moreno Aitor , Fieber Wolfgang , Brauchli Robert , Sommer Horst
Published: January 2015

Isomeric mixtures from synthetic or natural origins can pose fundamental challenges for their chromatographic separation and spectroscopic identification. A novel 1D selective NMR experiment, chemical shift selective filter (CSSF)‐TOCSY‐INEPT, is presented that allows the extraction of 13C NMR subspectra of discrete isomers in complex mixtures without physical separation. This is achieved via CSS excitation of proton signals in the 1H NMR mixture spectrum, propagation of the selectivity by polarization transfer within coupled 1H spins, and subsequent relaying of the magnetization from 1H to 13C by direct INEPT transfer to generate 13C NMR subspectra. Simple consolidation of the subspectra yields 13C NMR spectra for individual isomers. Alternatively, CSSF‐INEPT with heteronuclear long‐range transfer can correlate the isolated networks of coupled spins and therefore facilitate the reconstruction of the 13C NMR spectra for isomers containing multiple spin systems. A proof‐of‐principle validation of the CSSF‐TOCSY‐INEPT experiment is demonstrated on three mixtures with different spectral and structural complexities. The results show that CSSF‐TOCSY‐INEPT is a versatile, powerful tool for deconvoluting isomeric mixtures within the NMR tube with unprecedented resolution and offers unique, unambiguous spectral information for structure elucidation. Copyright © 2014 John Wiley & Sons, Ltd.
Effect of caffeine on intrinsic mechanical properties of normal and malignant hyperthermia‐susceptible muscle
Authors: Metterlein Thomas , Hartung Edmund , Roewer Norbert , Anetseder Martin
Published: January 2015

Introduction

Malignant hyperthermia (MH) is a potentially lethal anesthesic complication. Pathological symptoms develop after exposure to triggering substances. It remains uncertain whether cellular alterations pre‐exist. Mechanical properties of isolated muscle bundles were examined before and after exposure to a triggering substance.

Methods

With prior written consent, muscle bundles of 12 MH‐susceptible (MHS) and 56 MH‐nonsusceptible (MHN) individuals were examined before and after exposure to incremental doses of caffeine. Mechanical properties (baseline tension, peak tension, time to peak tension, and relaxation time) were measured. Contraction and relaxation derivatives and contraction–relaxation coupling were calculated and analyzed.

Results

Mechanical properties were not different between the groups before caffeine application. Caffeine increased peak tension in both groups and baseline tension only in MHS muscle bundles; relaxation time/derivative and contraction–relaxation coupling were prolonged.

Conclusions

Cellular changes seen in MH are not pre‐existing. Exposure to triggering substance impairs relaxation in MHS muscle. Muscle Nerve 52: 580–583, 2015
Hydrophobic photopolymerizable nanostructured hybrid materials: An effective solution for the protection of porous stones
Authors: Esposito Corcione C. , Striani R. , Frigione M.
Published: January 2015

In order to guarantee a very high preservation of stone artworks from water actions, an experimental superhydrophobic photopolymerizable organic–inorganic (O‐I) nanostructured hybrid product, namely HEP, has been developed and tested on a calcarenitic stone characteristic of Apulia Region (Italy), i.e., Pietra Leccese (PL). HEP is a “green” product, not containing harmful solvents, and is able to quickly set and harden at room temperature. The first part of the work was devoted to the analysis of the dimension of the silica nanodomains and the suitability of the liquid system produced to be applied on stone surfaces. To this aim, dynamic light scattering and rheological analyses were performed after different times from the preparation of the O‐I system. The hybrid mixture was subsequently applied on a glass substrate and photopolymerized by UV lamp. Several physical properties (glass transition temperature, transparency, scratch, and surface hardness) were, then, measured on the hybrid coating: a substantial improvement of all the surface properties measured was observed. HEP was, finally, applied on PL elements and different analytical techniques (contact angle, colorimetric and water absorption measurements, liquid water, and vapor water transmission) were used to fully characterize the product in terms of hydrophobicity, protective efficacy, water penetration resistance, and transpiring capability. The protective properties of the novel hybrid coating were also compared with those of two commercial water‐repellent products, applied on the same stone substrate, evidencing that the experimental coating is able to equal the performance of high‐quality commercial products. POLYM. COMPOS., 36:1039–1047, 2015. © 2015 Society of Plastics Engineers
Reflectance analysis on the MOCVD growth of AlN on Si(111) by the virtual interface model
Authors: Ng Tuoh‐Bin , Ewoldt David A. , Shepherd Debra A. , Loboda Mark J.
Published: January 2015

The reflectance‐time profile of AlN‐on‐Si(111) growth by MOCVD as acquired through an in‐situ optical reflectance monitor is analyzed. It is found that, similar to the case of GaN‐on‐sapphire nucleation and growth through the low temperature GaN or AlN buffer layer techniques, the reflectance profile for AlN‐on‐Si also contains information that relate to the growth mechanism, which can then be correlated to the as‐grown material quality. Based on the equations for the Virtual Interface model, a set of 6 parameters can be used to curve‐fit the reflectance traces of AlN growth as acquired by the in‐situ optical monitor. By analyzing a range of 405 nm AlN reflectance‐time data from single layer AlN growth to multilayer AlN/AlGaN/GaN stack grown on Si(111), the “goodness of fit” statistics are found to correlate with material quality metrics such as the XRD (002) rocking curve FWHM for AlN, microscopic morphological roughness of the AlN surface, as well as the resultant wafer bow and curvature for GaN/AlGaN grown on the AlN/Si(111) substrate. The correlations provide useful insight into the desirable mechanism and growth mode for the high temperature MOCVD growth of AlN and GaN on Si(111). When fully established, the technique has the potential of being used as an in‐situ pass/fail screen for the MOCVD growth of GaN‐on‐Si. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of boundary‐layer cloud forecasts over the Southern Ocean in a limited‐area numerical weather prediction system usingin situ, space‐borne and ground‐based observations
Authors: Huang Yi , Franklin Charmaine N. , Siems Steven T. , Manton Michael J. , Chubb Thomas , Lock Adrian , Alexander Simon , Klekociuk Andrew
Published: January 2015

Near‐synchronized in situ, space‐borne (A‐Train) and ground‐based lidar observations are employed to evaluate the boundary‐layer clouds (BLCs) over Tasmania and the adjacent Southern Ocean (SO) simulated by the limited‐area version of Australian Community Climate and Earth System Simulator (ACCESS‐C). Two winter cases featuring BLCs associated with a post‐frontal environment and the leading side of a high‐pressure ridge are studied. Previous studies showed that these synoptic conditions contribute to the largest reflected short‐wave radiation biases simulated over the SO.

Results of the simulations suggest that the ACCESS‐C model demonstrates an appreciable level of skill in simulating the macrophysical properties of the BLCs over the SO, generally consistent with the in situ and remote‐sensing observations. However, some notable challenges remain: the area cloud fraction of the marine BLCs is consistently underpredicted; the fine‐scale structure of the marine cumuli is poorly represented in the 4 km grid‐length simulations; the capping inversion over the marine boundary layer is generally too high, associated with the marine BLCs being predicted at the wrong altitude and temperature ranges; the liquid water content (LWC) of the BLCs is underestimated; and the model representation of drizzle production can be too efficient.

Sensitivity studies are also conducted to test a newly developed autoconversion microphysics scheme and shear‐dominated planetary boundary‐level (PBL) scheme. These parametrizations show notable improvement in cloud prediction for CASE B (i.e. better area cloud fraction and better average and maximum values of LWC). However, none of these tests is able to improve the simulated marine PBL structure. Overall, the simulated cloud biases are jointly influenced by physical parametrizations, poor representations of large‐scale advection, surface fluxes and subsidence. More substantial observations are needed to improve our understanding of the origins and development of these biases and the relative contribution of these errors to the radiation budget over the SO.
Vertical motions of the tropical convective cloud spectrum over Darwin, Australia
Authors: Schumacher Courtney , Stevenson Stephanie N. , Williams Christopher R.
Published: January 2015

Three months of profiler observations from Darwin, Australia are separated into seven cloud types (shallow, mid‐level, and deep convective; weak and robust stratiform rain; and transitional and ice‐only anvil) to provide vertical velocity statistics on the full spectrum of tropical convective clouds over the course of a monsoon season. Consistent with past studies, convective updraughts increase in height and magnitude as the convective cloud height increases. Shallow/mid‐level/deep convection has a mean maximum value of 0.3 m s−1 at 3 km/0.6 m s−1 at 5 km/2.5 m s−1 at 8 km. Deep convective extremes approach 18 m s−1 above 8 km while downdraughts in all convective cloud types are maximum below 4 km. Stratiform vertical velocities are weaker and less varied than in active convection, with maximum mean values <0.25 m s−1. However, stratiform rain regions associated with larger near‐surface reflectivities (and thus rain rates) have stronger mesoscale up‐ and downdraughts than weaker stratiform rain regions. Anvil cloud with little or no rain near the surface also exhibits mesoscale up‐ and downdraughts, but the vertical velocity profile is shifted up in height by at least 2 km. In addition, anvil updraughts were only 20–50% of the magnitudes in the stratiform rain region. Overall, the vertical motion statistics were similar across the pre‐, active and suppressed monsoon periods. The vertical velocity distributions for each cloud type were also generally consistent with the reflectivity distributions (i.e. the strongest updraughts were often linked to the largest reflectivities), allowing for some linkages between the dynamical and microphysical cloud properties. For example, strong updraughts above the 0 °C level in deep convection are associated with strongly sloping reflectivity profiles supporting the importance of cold rain growth processes, and stronger vertical motions are associated with stratiform rain that has a robust bright band.
Valkyrie: NASA's First Bipedal Humanoid Robot
Authors: Radford Nicolaus A. , Strawser Philip , Hambuchen Kimberly , Mehling Joshua S. , Verdeyen William K. , Donnan A. Stuart , Holley James , Sanchez Jairo , Nguyen Vienny , Bridgwater Lyndon , Berka Reginald , Ambrose Robert , Myles Markee Mason , Fraser‐Chanpong N. J. , McQuin Christopher , Yamokoski John D. , Hart Stephen , Guo Raymond , Parsons Adam , Wightman Brian , Dinh Paul , Ames Barrett , Blakely Charles , Edmondson Courtney , Sommers Brett , Rea Rochelle , Tobler Chad , Bibby Heather , Howard Brice , Niu Lei , Lee Andrew , Conover Michael , Truong Lily , Reed Ryan , Chesney David , Platt Robert , Johnson Gwendolyn , Fok Chien‐Liang , Paine Nicholas , Sentis Luis , Cousineau Eric , Sinnet Ryan , Lack Jordan , Powell Matthew , Morris Benjamin , Ames Aaron , Akinyode Jide
Published: January 2015

In December 2013, 16 teams from around the world gathered at Homestead Speedway near Miami, FL to participate in the DARPA Robotics Challenge (DRC) Trials, an aggressive robotics competition partly inspired by the aftermath of the Fukushima Daiichi reactor incident. While the focus of the DRC Trials is to advance robotics for use in austere and inhospitable environments, the objectives of the DRC are to progress the areas of supervised autonomy and mobile manipulation for everyday robotics. NASA's Johnson Space Center led a team comprised of numerous partners to develop Valkyrie, NASA's first bipedal humanoid robot. Valkyrie is a 44 degree‐of‐freedom, series elastic actuator‐based robot that draws upon over 18 years of humanoid robotics design heritage. Valkyrie's application intent is aimed at not only responding to events like Fukushima, but also advancing human spaceflight endeavors in extraterrestrial planetary settings. This paper presents a brief system overview, detailing Valkyrie's mechatronic subsystems, followed by a summarization of the inverse kinematics‐based walking algorithm employed at the Trials. Next, the software and control architectures are highlighted along with a description of the operator interface tools. Finally, some closing remarks are given about the competition, and a vision of future work is provided.
PDA: a privacy‐preserving dual‐functional aggregation scheme for smart grid communications
Authors: Li Chen , Lu Rongxing , Li Hui , Chen Le , Chen Jie
Published: January 2015

Privacy‐preserving aggregation for smart grid communications, which precisely meets the requirement of periodically collecting users' electricity consumption while preserving privacy of each individual user, has been extensively studied in recent years. However, most of existing privacy‐preserving aggregation schemes are only focused on the summation aggregation. In this paper, based on the lattice cryptographic technique, we propose a novel privacy‐preserving dual‐functional aggregation scheme (PDA) for smart grid communications. With our proposed PDA scheme, each individual user just reports one data, then multiple statistic values, that is, mean and variance, of all users can be computed by the data & control center in the smart grid, while the privacy of each individual user can still be protected. Detailed security analyses demonstrate that our proposed PDA scheme is secure and robust. In addition, extensive performance evaluations also show that our proposed PDA scheme is efficient in terms of computational and communication overheads when the number of considered users is within an acceptable range. Copyright © 2015 John Wiley & Sons, Ltd.
On model selections for repeated measurement data in clinical studies
Authors: Zou Baiming , Jin Bo , Koch Gary G. , Zhou Haibo , Borst Stephen E. , Menon Sandeep , Shuster Jonathan J.
Published: January 2015

Repeated measurement designs have been widely used in various randomized controlled trials for evaluating long‐term intervention efficacies. For some clinical trials, the primary research question is how to compare two treatments at a fixed time, using a t‐test. Although simple, robust, and convenient, this type of analysis fails to utilize a large amount of collected information. Alternatively, the mixed‐effects model is commonly used for repeated measurement data. It models all available data jointly and allows explicit assessment of the overall treatment effects across the entire time spectrum. In this paper, we propose an analytic strategy for longitudinal clinical trial data where the mixed‐effects model is coupled with a model selection scheme. The proposed test statistics not only make full use of all available data but also utilize the information from the optimal model deemed for the data. The performance of the proposed method under various setups, including different data missing mechanisms, is evaluated via extensive Monte Carlo simulations. Our numerical results demonstrate that the proposed analytic procedure is more powerful than the t‐test when the primary interest is to test for the treatment effect at the last time point. Simulations also reveal that the proposed method outperforms the usual mixed‐effects model for testing the overall treatment effects across time. In addition, the proposed framework is more robust and flexible in dealing with missing data compared with several competing methods. The utility of the proposed method is demonstrated by analyzing a clinical trial on the cognitive effect of testosterone in geriatric men with low baseline testosterone levels. Copyright © 2015 John Wiley & Sons, Ltd.
Endocrine hormones and local signals during the development of the mouse mammary gland
Authors: Brisken Cathrin , Ataca Dalya
Published: January 2015

Most of mammary gland development occurs postnatally under the control of female reproductive hormones, which in turn interact with other endocrine factors. While hormones impinge on many tissues and trigger very complex biological responses, tissue recombination experiments with hormone receptor‐deficient mammary epithelia revealed eminent roles for estrogens, progesterone, and prolactin receptor (PrlR) signaling that are intrinsic to the mammary epithelium. A subset of the luminal mammary epithelial cells expresses the estrogen receptor α (ERα), the progesterone receptor (PR), and the PrlR and act as sensor cells. These cells convert the detected systemic signals into local signals that are developmental stage‐dependent and may be direct, juxtacrine, or paracrine. This setup ensures that the original input is amplified and that the biological responses of multiple cell types can be coordinated. Some key mediators of hormone action have been identified such as Wnt, EGFR, IGFR, and RANK signaling. Multiple signaling pathways such as FGF, Hedgehog, and Notch signaling participate in driving different aspects of mammary gland development locally but how they link to the hormonal control remains to be elucidated. An increasing number of endocrine factors are appearing to have a role in mammary gland development, the adipose tissue is increasingly recognized to play a role in endocrine regulation, and a complex role of the immune system with multiple different cell types is being revealed. WIREs Dev Biol 2015, 4:181–195. doi: 10.1002/wdev.172

This article is categorized under:

Gene Expression and Transcriptional Hierarchies > Cellular Differentiation

Signaling Pathways > Global Signaling Mechanisms

Signaling Pathways > Cell Fate Signaling
Achalasia and Epiphrenic Diverticulum
Authors: Fisichella P. Marco , Jalilvand Anahita , Dobrowolsky Adrian
Published: January 2015

Epiphrenic diverticula are a rare disease almost always associated with an underlying motility disorder of the esophagus, such as achalasia. Treatment of any underlying motility disorder must be included in the management of epiphrenic diverticula to prevent postoperative complications and recurrences. Therefore, the goal of this paper is to describe the pathophysiology, clinical presentation, and proper methods of diagnosis and treatment of patients with epiphrenic diverticula. In addition, we aim to provide an overview of the surgical management and discuss the indications for surgery and choice of surgical approach. In general, surgical intervention is favored for symptomatic patients and the optimal surgical approach depends on the size and location of the diverticulum. Surgery is not without seemingly high rates of morbidity when a myotomy is not performed together with the diverticulectomy, even in those with normal manometry. The risk of carcinoma is exceedingly rare and it is usually discovered at later stages; therefore, no surveillance programs have been established in asymptomatic patients with unresected diverticula.