bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monotone Smoothing Splines using General Linear Systems
Authors: Nagahara Masaaki , Martin Clyde F. 
Published: June 2012

AbstractIn this paper, a method is proposed to solve the problem of monotone smoothing splines using general linear systems. This problem, also called monotone control theoretic splines, has been solved only when the curve generator is modeled by the second‐order integrator, but not for other cases. The difficulty in the problem is that the monotonicity constraint should be satisfied over an interval which has the cardinality of the continuum. To solve this problem, we first formulate the problem as a semi‐infinite quadratic programming problem, and then we adopt a discretization technique to obtain a finite‐dimensional quadratic programming problem. It is shown that the solution of the finite‐dimensional problem always satisfies the infinite‐dimensional monotonicity constraint. It is also proved that the approximated solution converges to the exact solution as the discretization grid‐size tends to zero. An example is presented to show the effectiveness of the proposed method.
Using the Discrete Element Method for Predicting the Mixing Behavior of Gravity Blenders in Different Operation Modes
Authors: Weiler R. , Ripp M. , Dau G. , Ripperger S. 
Published: June 2012

AbstractThe application of residence time density distributions gained with discrete element method (DEM) simulations for predicting the mixing behavior of gravity blenders in different operation modes is presented. Knowing these distributions, the performance of a blender can be predicted during different blending tasks in continuous and discontinuous operation mode. Up to now, the residence time distributions needed for these predictions could only be measured. It will be explained how a gravity blender containing more than 1 million of particles is mapped to simulation considering the computational effort as well as the quantitative validity of the results. Based on these data, the discontinuous blending behavior is predicted. The results indicate good agreement between simulations and experimental data and can serve as a basis for designing gravity blenders.
Synthesis and Molecular Modeling Studies of Derivatives of a Highly Potent Peptidomimetic Vinyl Ester as Falcipain‐2 Inhibitors
Authors: Ettari Roberta , Micale Nicola , Grazioso Giovanni , Bova Floriana , Schirmeister Tanja , Grasso Silvana , Zappalà Maria 
Published: June 2012

AbstractHerein we report the synthesis of a set of constrained peptidomimetics endowed with an electrophilic vinyl ester warhead and structurally related to a previously identified lead compound, a potent and irreversible inhibitor of falcipain‐2 (FP‐2). FP‐2 is the main hemoglobinase of the malaria parasite P. falciparum. The new compounds were evaluated for their inhibition against FP‐2, and the results were rationalized on the basis of docking experiments. These studies underscore the pivotal role of both the ester function at the P1′ site and the trifluoromethyl group of the P3 side chain in determining the correct orientation of the Michael acceptor warhead in the catalytic site, and as a consequence, the potency of the inhibitors as well as their reversible or irreversible mode of inhibition.
Electrochemistry in Reverse Biased Dye Solar Cells and Dye/Electrolyte Degradation Mechanisms
Authors: Mastroianni Simone , Lembo Angelo , Brown Thomas M. , Reale Andrea , Di Carlo Aldo 
Published: June 2012

AbstractMismatched or shadowed individual cells in a module can operate in the reverse bias (RB) regime. We investigate and identify key mechanisms for RB operation and degradation in dye solar cells (DSCs). Current–voltage characteristics in RB are sensitive to the type of dye utilised and to TiCl4 substrate treatment. Subjecting the cell to a RB of 0.4 V over 740 h has little effect on conversion efficiency whereas a significant lowering is observed for the harsher stress tests at 0.6 V and by forcing a constant current equal to its ISC. For more prolonged reverse biases at ISC (>740 h), we show that depletion of [I3−] inside the DSC can lead the reverse bias potentials across the cells to considerably increase in time. Electrochemical impedance measurements show that the overpotentials at the counter electrodes (CEs) can eventually reach values high enough to cause hydrogen evolution. Clear evidence of gas bubbles forming inside a complete dye solar cell under reverse bias stress, leading to severe device degradation, is presented. We also show that reactions of iodine with water present in the electrolyte can play an important role in [I3−] depletion and in the formation of hydrogen at the Pt CE.
ETV2 expression marks blood and endothelium precursors, including hemogenic endothelium, at the onset of blood development
Authors: Wareing Sarah , Eliades Alexia , Lacaud Georges , Kouskoff Valerie 
Published: June 2012

AbstractBackground: ETV2 has been identified as an important player in embryonic hematopoiesis. However, the cell populations in which this transcription factor is expressed and operates during blood specification remain to be fully characterized. Here we address these issues using ES cells and a transgenic mouse line expressing green fluorescent protein (GFP) under the control of ETV2 regulatory elements, allowing us to observe the tight association between ETV2 expression and the initiation of hematopoiesis. Results: Both in differentiating ES cells and gastrulating embryos ETV2::GFP is mostly found co‐expressed with endothelial markers and defines a subset of cells with greatly enriched primitive erythroid potential. Upon culture ETV2::GFP cells rapidly up‐regulate CD41, down‐regulate endothelium cell surface markers and generate definitive hematopoietic progenitors. Altogether these characteristics represent the hallmark of hemogenic endothelium cells, a specialized endothelium originating from the hemangioblast and giving rise to hematopoietic cells. Importantly, ETV2 deficiency results in a complete absence of hemogenic endothelium in differentiating ES cells and gastrulating embryos. Conclusions: Altogether our data reveal that ETV2 marks hemogenic endothelium in gastrulating embryos and is absolutely required for the formation of this precursor at the onset of hematopoiesis. These results enhance our understanding of embryonic hematopoiesis and the factors driving hemogenic endothelium specification. Developmental Dynamics 241:1454–1464, 2012. © 2012 Wiley Periodicals, Inc.
Cellular phenotypes and spatio‐temporal patterns of lymphatic vessel development in embryonic mouse hearts
Authors: Flaht A. , Jankowska‐Steifer E. , Radomska D.M. , Madej M. , Gula G. , Kujawa M. , Ratajska A. 
Published: June 2012

AbstractBackground: The origin of cardiac lymphatics from venous endothelial cells or from scattered lymphangioblasts has been discussed in the literature. We aimed to establish the stage when lymphatic vessels appear in the developing mouse heart, the location of the first lymphatics, and to define cellular phenotypes of growing lymphatics. Results: We found that scattered Lyve‐1‐positive cells located in the subepicardial area of developing heart expressed CD45, CD68, F4/80, or CD11b but not CD31. Prox‐1+/Lyve‐1+ cellular cords or vessels were found to invade 12.5–13.5‐dpc hearts via two routes: from the venous pole, i.e., dorsal atrioventricular sulcus, or on the dorsal atrial surface from mediastinum and from the arterial pole, i.e., along the great arteries. The Prox‐1+/Lyve‐1+ vessels were located among the Prox‐1+/Lyve‐1− cords and among the scattered Prox‐1−/Lyve‐1+ cells. The Prox‐1+/Lyve‐1− cellular cords/tubules dominate initially at the arterial pole whereas Lyve‐1+/Prox‐1− cellular cords/tubules dominate initially on the venous pole, i.e., dorsal atrioventricular sulcus. The Lyve‐1+/CD45+, Lyve‐1+/CD11b+, Lyve‐1+/F4/80+ and Lyve‐1+/CD68+ cells were subsequently found to be co‐opted to the wall of the developing lymphatic vessels while gaining Flk‐1. Conclusions: Lymphatic primordia exhibit different cellular phenotypes and different spatiotemporal pattern on the venous pole as compared with the arterial pole of the heart. Developmental Dynamics 241:1473–1486, 2012. © 2012 Wiley Periodicals, Inc.
Oxidorhenium(V) Complexes with Phenolate‐ and Carboxylate‐Based Ligands: Structure and Catalytic Epoxidation
Authors: Machura Barbara , Wolff Mariusz , Tabak Dominik , Schachner Jörg A. , Mösch‐Zanetti Nadia C. 
Published: June 2012

AbstractSeveral oxidorhenium(V) complexes with phenolate‐ and carboxylate‐based ligands were synthesized: [ReOCl(hpbi)2]·THF, [ReOCl(hmpbta)2], [ReOBr(hmpbta)2], [ReOCl(hpbo)2], [ReOCl(hpbt)2]·2MeCN, [ReO(OMe)(quin)2], [ReO(OMe)(pic)2], [ReO(OMe)(2,5‐dipic)2]·C5H5N, [ReOCl(pic)2], and [ReOCl(3‐ind)2] [in which Hhpbi = 2‐(2‐hydroxyphenyl)‐1H‐benzimidazole, Hhmpbta = 2‐(2‐hydroxy‐5‐methylphenyl)benzotriazole, Hhpbo = 2‐(2‐hydroxyphenyl)‐2‐benzoxazole, Hhpbt = 2‐(2‐hydroxyphenyl)benzothiazole, Hquin = quinaldic acid, picH = picolinic acid, 2,5‐dipicH = 2,5‐pyridinedicarboxylic acid, and 3‐indH = indazole‐3‐carboxylic acid]. The compounds were characterized by spectroscopic methods and single‐crystal X‐ray diffraction analysis. Interestingly, the complex [ReO(OMe)(quin)2] is a rare trans‐N,N and trans‐O,O isomer of [ReOX(N–O)2] with two chelating quinoline‐2‐carboxylate ligands in the equatorial plane and a linear axial [O=Re–OMe] unit. The other disubstituted compounds were found to be the most common cis‐N,N structure of [ReOX(N‐O)2] with the oxygen atom of one of the chelating ligands in a trans position to the oxido ligand. All the complexes were tested in the epoxidation of cyclooctene with tert‐butyl hydroperoxide (3 equiv.). The lowest conversion of only 3 % has been confirmed for [ReOCl(hpbi)2]. All other complexes reached yields of cyclooctane oxide between 58 and 75 %.
1H‐Isoindole‐Based Potential Peptidomimetics
Authors: Biitseva Angelina V. , Rudenko Igor V. , Hordiyenko Olga V. , Jamart‐Grégoire Brigitte , Arrault Axelle 
Published: June 2012

AbstractA variety of 1H‐isoindole‐based peptides was designed as potential mimics, and their efficient synthesis starting from 1‐imino‐1H‐isoindol‐3‐amine by subsequent interaction with N‐Boc‐amino acid hydrazides and amino acid ester isocyanates generated in situ, followed by chain elongation using conventional peptide chemistry, was elaborated.
Redox state alters anti‐cancer effects of wedelolactone
Authors: Benes Petr , Alexova Petra , Knopfova Lucia , Spanova Alena , Smarda Jan 
Published: June 2012

AbstractWedelolactone is one of the active plant polyphenolic compounds. Anti‐tumor effects of this drug have been demonstrated recently. We have described that wedelolactone acts as catalytic inhibitor of DNA topoisomerase IIα. The aim of this study was to further characterize the mechanism of its anti‐tumor effects. We showed that wedelolactone inhibits binding of DNA topoisomerase IIα to plasmid DNA and antagonizes formation of etoposide‐induced DNA cleavage complex. The inhibition of topoisomerase IIα by wedelolactone is reversible by excess of the enzyme but not DNA. The in vitro inhibitory effect of wedelolactone on the topoisomerase IIα activity is redox‐dependent as it diminished in the presence of reducing agents. Cytotoxicity of wedelolactone was partially inhibited by N‐acetylcysteine and glutathione ethyl ester in breast cancer MDA‐MB‐231 and MDA‐MB‐468 cells while the inhibitory effect of catalase was observed only in the former cell line. Finally, we found that wedelolactone can be oxidized in the presence of copper ions resulting in DNA strand break and abasic site formation in vitro. However, wedelolactone induced neither DNA damage in MDA‐MB‐231 cells nor mutations in bacterial cells detectable by Ames test suggesting that wedelolactone may not be an effective inducer of DNA damage. We conclude that the topoisomerase IIα inhibitory‐ and DNA damaging activities of wedelolactone in vitro depend on its redox state. Pro‐oxidant activity could, however, explain only part of wedelolactone‐induced cytotoxicity. Therefore, the major cellular target(s) of wedelolactone and the exact mechanism of wedelolactone‐induced cytotoxicity still remain to be identified. Environ. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc.
Depression and cardiovascular risk factors: evidence from a large postmortem sample
Authors: Suemoto Claudia K. , Damico Marcio V. , Ferretti Renata E. L. , Grinberg Lea T. , Farfel José Marcelo , Leite Renata E. P. , Nitrini Ricardo , Lafer Beny , Jacob‐Filho Wilson , Pasqualucci Carlos A. , Group Brazilian Aging Brain Study 
Published: June 2012

ObjectivesWe aimed to investigate the association of depression with cardiovascular risk factors and diseases (CVRFD) in a large population‐based sample.MethodsThis cross‐sectional study included 1012 deceased individuals greater than 50 years of age from a general autopsy service located in São Paulo, Brazil. Demographics, socioeconomic profile, and CVRFD information were collected by caregivers from the deceased individuals from the Brain Bank of the Brazilian Aging Brain Study Group. Depression diagnosed using the Structured Clinical Interview for Diagnostic and Statistical Mental Disorders was the main outcome.ResultsDepression was associated with female gender (odds ratio (OR) = 1.86; 95% confidence interval (CI) = 1.28–2.71, p = 0.001), widowhood (OR = 1.54; 95% CI = 1.03–2.32, p = 0.04), physical inactivity (OR = 1.61; 95% CI = 1.15–2.26, p = 0.006), and smoking (OR = 2.03; 95% CI = 1.40–2.95, p < 0.001) after multivariate logistic regression analysis. Other CVRFD were not associated with the presence of depression.ConclusionsIn our cross‐sectional study, sedentary individuals and smokers showed a higher chance of depression during lifetime. Measures to control these common risk factors could decrease the incidence of depression. Copyright © 2012 John Wiley & Sons, Ltd.
The Relative Importance of Usability and Functionality Factors for E‐Health Web Sites
Authors: Topaloglu Hande , Gumussoy Cigdem Altin , Bayraktaroglu Ayse Elvan , Calisir Fethi 
Published: June 2012

AbstractWith the growing usage of the Internet, the demand for online health care information and advice as well as the number of health‐related Web sites are increasing. In case of online health information and advice, the user interface replaces face‐to‐face communication. To ensure that the users' needs are met, it is critical to balance functionality and usability in the design of the Web site. The present study seeks to identify the complex interrelationships among the various factors of usability and functionality concerning e‐health Web sites. Two Turkish e‐health Web sites were assessed for evaluation in this study. The findings show that the users of the health information Web sites give a higher priority to functionality and its factors, whereby the highest relative importance is on “services/facilities” and “personalization/categorization of information.” The most important usability factors related to the e‐health Web sites are “memorability” and “interaction.” © 2012 Wiley Periodicals, Inc.
A gentamicin‐releasing coating for cementless hip prostheses—Longitudinal evaluation of efficacy using in vitro bio‐optical imaging and its wide‐spectrum antibacterial efficacy
Authors: Neut Daniëlle , Dijkstra René J. B. , Thompson Jonathan I. , van der Mei Henny C. , Busscher Henk J. 
Published: June 2012

AbstractCementless prostheses are increasingly popular in total hip arthroplasties. Therewith, common prophylactic measures to reduce the risk of postoperative infection like the use of antibiotic‐loaded bone cements, will no longer be available. Alternative prophylactic measures may include the use of antibiotic‐releasing coatings. Previously, we developed a gentamicin‐releasing coating for cementless titanium hip prostheses and derived an appropriate dosing of this coating by adjusting the amount of gentamicin in the coating to match the antibacterial efficacy of clinically employed gentamicin‐loaded bone cement. In this manuscript, we investigated two important issues regarding the prophylactic use of this 1 mg cm−2 bioactive gentamicin‐releasing coating in cementless total hip arthroplasty: (1) its ability to prevent bacterial growth in a geometrically relevant set‐up and (2) its antibacterial spectrum. A geometrically relevant set‐up was developed in which miniature titanium stems were surrounded by agar, contaminated with bioluminescent Staphylococcus aureus. Novel, bio‐optical imaging was performed allowing noninvasive, longitudinal monitoring of staphylococcal growth around miniature stems with and without the gentamicin‐releasing coating. Furthermore, the antibacterial efficacy of the gentamicin‐releasing coating was determined against a wide variety of clinical isolates, including bioluminescent Staphylococcus aureus strains, using traditional zone of inhibition measurements. The gentamicin‐releasing coating demonstrated a wide‐spectrum of antibacterial efficacy and successfully prevented growth of bioluminescent staphylococci around a miniature stem mounted in bacterially contaminated agar for at least 60 h. This implies that the gentamicin‐releasing coating has potential to contribute to the improvement of infection prophylaxis in cementless total hip arthroplasty. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3220–3226, 2012.
Chitosan and polycaprolactone membranes patterned via electrospinning: Effect of underlying chemistry and pattern characteristics on epithelial/fibroblastic cell behavior
Authors: Şimşek Murat , Çapkın Merve , Karakeçili Ayşe , Gümüşderelioğlu Menemşe 
Published: June 2012

AbstractElectrospinning was used as an effective route to pattern chitosan (CS) and polycaprolactone (PCL) membranes with submicron fibers having different chemical structure (PCL or PCL/collagen) and physical characteristics (size: between ≈200 and 550 nm; randomly oriented or aligned form). While the PCL fibers with diameters in the same range (≈200 nm) were patterned on both of CS and PCL membranes to evaluate the influence of the underlying membrane chemistry, only CS membranes were patterned with PCL fibers having different sizes simply by changing the electrospinning conditions to investigate the effects of pattern characteristics. Furthermore, collagen was added to the PCL fiber structure to change the chemical composition of the fibers in a cell‐attractive way. Two cell lines with different morphologies, fibroblastic MC3T3‐E1 preosteoblasts and epithelial Madine Darby Bovine Kidney (MDBK) cells, were cultured on the patterned membranes. The observation of cellular behavior in terms of cell morphology and F‐actin synthesis was realized by scanning electron microscopy and confocal microscopy analysis during the first 12 h of culture period. The viability of cells was controlled by MTT assay through 96 h of cell culture. The cell culture studies indicated that the leading aspect for the morphology change on patterned membranes was the fiber orientation. The aligned topography controlled the morphology of cells both on CS and PCL membranes. In the presence of collagen in the fiber structure, F‐actin filament synthesis increased for MC3T3‐E1 and MDBK cell lines. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3332–3343, 2012.
Plant growth promotion traits and Cr (VI) reduction potentials of Cr (VI) resistant Streptomyces strains
Authors: Javaid Mahwish , Sultan Sikander 
Published: June 2012

AbstractThe most toxic form of chromium [Cr (VI)] can be converted to less toxic Cr (III) by reduction with the help of microbes. A total of 6 Streptomyces strains (S. matansis BG5, Streptomyces sp. RSF17, S. vinaceus CRF2, Streptomyces sp. CRF14, S. pulcher CRF17, S. griseoincarnatus SCF18) which were previously isolated from saline farmlands of Punjab, Pakistan, were used in this work. These strains showed varying levels of resistance to Cr (VI) from 800 μg ml−1 to 1000 mg l−1. Their plant growth promoting and Cr (VI) reduction potentials were assessed. Two strains showed positive phosphate solubilization activity. All the strains had ability to produce indole acetic acid (IAA) except one strain (CRF17). The maximum production of IAA was observed by strain BG5 that was 16 mg l−1 in the presence of 50 mg l−1 of Cr (VI). All the strains were able to produce ammonia both in the absence and presence of Cr (VI). The highest Cr (VI) reduction in majority of the strains was observed at 28 °C and pH 9. The complete reduction of 150 mg l−1 of Cr (VI) occurred after 168 hrs. The chromium (VI) concentration of 200 mg l−1 could be reduced above 90% by most of these strains. The presence of other metals also enhanced Cr (VI) reduction by most of the strains. The results indicate the potential capacity of Streptomyces strains as tool for plant growth promotion and Cr (VI) bioremediation and also is the first report about plant growth promoting traits of Cr (VI) resistant Streptomyces strains.
Direct effects of triiodothyronine on production of anterior pituitary hormones and gonadal steroids in goldfish
Authors: Allan Euan R.O. , Habibi Hamid R. 
Published: June 2012

AbstractThe present study investigated the effects of triiodothyronine (T3) on pituitary gonadotropin (GTH) subunits, thyroid stimulating hormone (TSH) β subunit, and growth hormone (GH) mRNA levels, as well as gonadal steroid secretion during different stages of reproduction in goldfish. Goldfish pituitary cells cultured with T3 exhibited lower tshβ mRNA levels in all reproductive stages and lower luteinising hormone β (lhβ) mRNA levels in early recrudescence, whereas gh and fshβ mRNA levels were not altered. T3 injections significantly reduced circulating oestrogen (OE2) concentrations in early and mid recrudescent male goldfish, but were without effect on the circulating level of OE2 in female fish. T3 injections also reduced circulating levels of testosterone in both male and female goldfish during the mid stage of gonadal recrudescence. In vitro culture of goldfish ovarian follicles at the late stage of gonadal recrudescence, in the presence of T3, resulted in reduced OE2 secretion; no consistent effect of T3 on testosterone secretion was observed in cultured goldfish ovarian follicles and testis. These findings support the hypothesis that T3 impairs reproduction by inhibiting production of gonadal steroids and pituitary luteinising hormone production in goldfish. Mol. Reprod. Dev. 79: 592–602, 2012. © 2012 Wiley Periodicals, Inc.