bluuebunny/crossref_metadata_2025_split huggingface dataset:
Joint Electrical, Photophysical, and Photovoltaic Studies on Truxene Dye‐Sensitized Solar Cells: Impact of Arylamine Electron Donors
Authors: Wang Zhihui , Liang Mao , Wang He , Wang Peng , Cheng Fangyi , Sun Zhe , Song Xue 
Published: February 2014

AbstractThe judicious design of electron donors is one of the viable tactics to improve the efficiency of organic dyes for dye‐sensitized solar cells (DSCs) employing outer‐sphere redox couples. Herein, a hexahexyltruxene‐substituted 4‐(hexyloxy)‐N‐phenylaniline (HT‐HPA) segment is constructed and employed as the electron donor in two organic push–pull dyes (M28 and M29) with high molar absorption coefficient values. Relative to its congener (C241) possessing the dihexyloxy‐substituted triphenylamine electron donor, M29 exhibits red‐shifted absorption as well as enhanced maximum molar absorption coefficient values. A thorough comparison with M29 and C241 demonstrates that the HT‐HPA segment adequately insulates the TiO2 surface from the electrolyte, which prevents back‐recombination and prolongs electron lifetime in the semiconductor. The diminishment of charge recombination not only enables attainment of strikingly high photovoltages (approaching 1 V), but also overcompensates the disadvantageous impact of lower dye‐load amounts. As a result, the dye transformation from C241 to M29 brings forth an efficiency improvement from 7.3 % to 8.5 % at the 100 mW cm−2 simulated AM1.5 conditions. Our work should shed light on the future design of more powerful push–pull organic photosensitizers for iodine‐free DSCs.
Cardiovascular mortality and chronotropic incompetence in systolic heart failure: the importance of a reappraisal of current cut‐off criteria
Authors: Magrì Damiano , Corrà Ugo , Di Lenarda Andrea , Cattadori Gaia , Maruotti Antonello , Iorio Annamaria , Mezzani Alessandro , Giannuzzi Pantaleo , Mantegazza Valentina , Gondoni Erica , Sinagra Gianfranco , Piepoli Massimo F. , Fiorentini Cesare , Agostoni Piergiuseppe 
Published: February 2014

AimsAn independent role for the exercise‐induced heart rate (HR) response—and specifically the chronotropic incompetence (CI)—in the prognosis of heart failure (HF) is still debated. The multicentre study reported here sought to investigate the prognostic values of HR and CI variables on cardiovascular mortality in a large cohort of systolic HF patients.Methods and resultsA total of 1045 HF patients were recruited and prospectively followed in three Italian HF centres. The study endpoint was cardiovascular mortality. Besides a full clinical examination, each patient underwent a maximal cardiopulmonary exercise test at study enrolment. The age‐predicted peak HR (%pHR) and the peak HR reserve (%pHRR) according to different cut‐off values (60–80% of the maximum predicted) were adopted to identify the presence of CI. The median follow‐up was 876 days (interquartile range 386–1590 days). Cardiovascular death occurred in 145 cases (13.8%). Besides LVEF, peak oxygen uptake, ventilation vs. carbon dioxide production slope, and beta‐blocker therapy, the multivariate analysis showed that both %pHR and %pHRR were able to predict prognosis when considered as continuous variables. Conversely, the presence of CI was associated with the study endpoint only when the 70% (%pHR <70%, hazard ratio 1.80, confidence interval 1.24–2.61, P = 0.002; %pHRR <70%, hazard ratio 1.77, confidence interval 1.09–2.86, P = 0.020) or the 65% cut‐off values (%pHR <65%, hazard ratio 2.04, confidence interval 1.34–3.10, P = 0.001; %pHRR <65%, hazard ratio 1.54, confidence interval 1.03–2.32, P = 0.038) were adopted.ConclusionsOur findings demonstrated an additive role of CI in stratifying cardiovascular mortality. Both the 65% and the 70% cut‐off values, regardless of the method (%pHR and %pHRR), allow identification of HF patients with the worst prognosis, thus supporting such definitions of CI in HF.
Discrepancy between echocardiographic and patient‐reported health status response to cardiac resynchronization therapy: results of the PSYHEART‐CRT study
Authors: Versteeg Henneke , van 't Sant Jetske , Cramer Maarten J. , Doevendans Pieter A. , Pedersen Susanne S. , Meine Mathias 
Published: February 2014

AimsThe current study examined the degree of agreement between echocardiographic and patient‐reported health status response to CRT 6 months after implantation, and evaluated the differences in pre‐implantation characteristics of patients with concordant and discordant echocardiographic and health status responses.Methods and resultsConsecutively implanted CRT‐defibrillator patients (n = 109, mean age = 65.4 ± 10.1 years, 74 men) were recruited from the University Medical Center Utrecht, The Netherlands. Prior to implantation and 6 months post‐implantation, all patients underwent echocardiography and completed the Kansas City Cardiomyopathy Questionnaire (KCCQ). Echocardiographic response was defined as a relative reduction of ≥15% in LV end‐systolic volume; an improvement of ≥10 points in KCCQ score indicated a health status response. In the 54 patients with discordant responses, 25 (22.9%) had an echocardiographic response but no health status response and 29 (26.6%) had a health status response but no echocardiographic response. Patients with concordant and discordant responses differed on various pre‐implantation characteristics, including sex, employment status, LV volumes, and pre‐implantation KCCQ score. In multivariable analysis, pre‐implantation KCCQ score [odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.88–0.95, P < 0.001] and QRS duration (OR = 1.03, 95% CI = 1.01–1.06, P = 0.009) were the only characteristics associated with health status response to CRT.ConclusionsOur results show a large discrepancy between echocardiographic and patient‐reported health status response to CRT. The most important predictor of health status response was the pre‐implantation health status score. These results emphasize that disease‐specific health status measures may have additional value over ‘objective’ measures of CRT response and should be incorporated in clinical practice.
Water Oxidation
Authors: Hetterscheid Dennis G. H. , Sun Licheng 
Published: February 2014

AbstractAn overview of the papers in this cluster issue is presented.“...in recent years, quite some progress has been made in our understanding of the catalytic water oxidation processes. In order to further boost the momentum of the field and to provide tools for new researchers entering the field of catalytic water oxidation, we have guest‐edited this Cluster Issue of EurJIC on water oxidation.”Read more by the Guest Editors on p. 571.
Enzymatic synthesis of amino sugar fatty acid esters
Authors: Pöhnlein Martin , Slomka Christin , Kukharenko Olga , Gärtner Tobias , Wiemann Lars O. , Sieber Volker , Syldatk Christoph , Hausmann Rudolf 
Published: January 2014

N‐Acetyl‐glucosamine fatty acid esters were synthesized by a lipase‐catalyzed transesterification with methyl hexanoate and N‐acetyl‐glucosamine (GlcNAc), which resulted in the formation of 2‐(acetylamino)‐2‐deoxy‐6‐O‐hexanoate‐D‐glucose, a novel glycolipid. Additionally N‐butyryl‐glucosamine (GlcNBu) was used for a similar synthesis, leading to the formation of 2‐(butyrylamino)‐2‐deoxy‐6‐O‐hexanoate‐D‐glucose. The higher hydrophobicity of GlcNBu led to an increase in the overall yield and the initial reaction rate when compared to the reaction with GlcNAc. By pre‐dissolving GlcNAc and GlcNBu in dimethyl sulfoxide (DMSO), it was possible to completely dissolve both sugars in the organic solvent, thus further enhancing the initial reaction rate and yield respectively.Practical applications: Glycolipids are used in a wide range of applications, ranging from food, cosmetic, and pharmaceutical formulations, where they can be used as emulsifiers or foaming agents to classic cleaning products, utilizing their good detergent properties. Further applications may include fields like membrane protein extraction, bioremediation, or tertiary oil recovery. Novel glycolipids with tailor‐made properties might be useful to improve any of the named applications and widen the diversity of available environmentally friendly surfactants, often termed “green surfactants.” Glycolipids are the most prominent example therefrom.
Ultraflexible Screen‐Printed Graphitic Electroanalytical Sensing Platforms
Authors: Foster Christopher W. , Metters Jonathan P. , Kampouris Dimitrios K. , Banks Craig E. 
Published: January 2014

AbstractThe pursuit of ultraflexible sensors has arisen from the recent implementation of electrochemical sensors into wearable clothing where extensive mechanical stress upon the sensing platform is likely to occur. Such scenarios have witnessed screen‐printed electrodes being incorporated into the waistband of undergarments for the determination of key analytes while others have reported incorporation into a neoprene wetsuit. In these conformations, the substrates which the sensors are printed upon need to be ultraflexible and capable of withstanding extensive individual mechanical stress. Therefore the composition, thickness and its combination of screen‐printed ink require extensive consideration. A common short‐coming within the field of screen‐printed derived sensors is the lack of consideration towards the substrate material employed, and is rather in favour of the development of new electrode geometries and screen‐printing inks. In this paper we explore the screen‐printing of graphite based electroanalytical sensing platforms onto graphic paper commonly used in house‐hold printers, and for the first time both tracing paper and ultraflexible polyester‐based substrates are used. These sensors are electrochemically benchmarked with the redox probes hexaammine‐ruthenium(III) chloride and potassium ferrocyanide(II). The effect of mechanical contortion upon two types of electrode substrates is also performed where it was found that these ultraflexible based polyester‐based electrodes are superior to the previously reported ultraflexible paper electrodes since they can withstand extensive mechanical contortion, yet they still give rise to useful electrochemical performances. Most importantly the ultraflexible polyester electrodes do not suffer from capillary action as observed in the case of paper‐based sensors causing the solution to wick‐up the electrode towards the electrical connections resulting in electrical shorting, therefore compromising the electrochemical measurement; as such this new substrate can be used as a replacement for paper‐based substrates and yet still be resilient to extreme mechanical contortion. A new configuration is also explored using these electrode substrate supports where the working carbon electrode contains the electrocatalyst, cobalt(II) phthalocyanine (CoPC), and is benchmarked towards the electroanalytical sensing of the model analytes citric acid and hydrazine which demonstrate excellent sensing capabilities in comparison to previously reported screen‐printed electrodes.
The Development of Highly Sensitive and Selective Immunosensor Based on Antibody Immobilized ZnO Nanorods for the Detection of D‐Dimer
Authors: Ibupoto Zafar H. , Mitrou Nikolaos , Nikoleli Georgia‐Paraskevi , Nikolelis Dimitrios P. , Willander Magnus , Psaroudakis Nikolas 
Published: January 2014

AbstractZnO nanorods were grown on gold coated glass substrate by low temperature aqueous chemical growth method. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) techniques were used for the characterization of ZnO nanorods. ZnO nanorods are highly dense, uniform, well aligned and perpendicular‐oriented to the substrate. ZnO nanorods exhibited good crystal quality. The well aligned ZnO nanorods were potentially used for the development of selective and sensitive immunosensor for the detection of D‐dimer by immobilizing antibody on stabilized lipid films. The ZnO nanorods based immunosensor responded to a wide range of D‐dimer concentrations with fast response time of ca. 20 s.
A nano‐LC/UV method for the analysis of principal phenolic compounds in commercial citrus juices and evaluation of antioxidant potential
Authors: Rocco Anna , Fanali Chiara , Dugo Laura , Mondello Luigi 
Published: January 2014

In this study, a simple and rapid methodology to analyze and quantify principal flavanones in citrus fruit juices through the use of a nano‐LC/UV‐Vis apparatus, employing a 75 μm id capillary column packed with sub‐2 μm particles C18 stationary phase for 10 cm, was developed. All compounds were baseline resolved working with a step gradient elution mode in 10 min. The developed analytical method was validated and the resulting RSD% for intra‐ and interday repeatability, related to retention time and peak area, were <4.7 and 5.5%, respectively. LOD and LOQ values corresponded to 0.40 and 1.56 μg/mL for didymin, hesperitin, and narinegenin, while for the other flavanones were 0.78 and 3 μg/mL, respectively. Good linearity with acceptable determination coefficients R2 was obtained in the range between LOQ concentration and 200 μg/mL (500 μg/mL naringin and hesperidin). Good recovery values were also obtained. Then, the method was applied to the analysis of selected hand‐squeezed and commercial citrus juices. Further, the nano‐LC system was coupled to a mass spectrometer to confirm analyte identification. Antioxidant capacity of selected samples was also evaluated measured by Folin–Ciocalteu assay and Trolox equivalent antioxidant capacity assay. Results were compared to determine total flavanones concentrations.
Dynamic response analysis of solitary flexible rocking bodies: modeling and behavior under pulse‐like ground excitation
Authors: Vassiliou Michalis F. , Mackie Kevin R. , Stojadinović Božidar 
Published: January 2014

SUMMARYResults obtained for rigid structures suggest that rocking can be used as seismic response modification strategy. However, actual structures are not rigid: structural elements where rocking is expected to occur are often slender and flexible. Modeling of the rocking motion and impact of flexible bodies is a challenging task. A non‐linear elastic viscously damped zero‐length spring rocking model, directly usable in conventional finite element software, is presented in this paper. The flexible rocking body is modeled using a conventional beam‐column element with distributed masses. This model is verified by comparing its pulse excitation response to the corresponding analytical solution and validated by overturning analysis of rocking blocks subjected to a recorded ground motion excitation. The rigid rocking block model provides a good approximation of the seismic response of solitary flexible columns designed to uplift when excited by pulse‐like ground motions. Guidance for development of rocking column models in ordinary finite element software is provided. Copyright © 2014 John Wiley & Sons, Ltd.
Empirical MIMO beamforming and channel measurements at 57–64 GHz frequencies
Authors: Ahmadi‐Shokouh J. , Rafi R. , Taeb A. , Safavi‐Naeini S. 
Published: January 2014

AbstractIn this paper, we employ a 4‐port Agilent PNA‐X network analyzer with the expansion modules to measure a 2 × 2 multi‐input multi‐output (MIMO) propagation channel at 57–64 GHz frequency band. Moreover, we investigate on the beamforming capabilities of the millimetre‐wave (MMW) MIMO system. For both aforementioned architectures, that is, regular MMW MIMO and MMW MIMO with beamforming, the Shanon capacity criterion is used to evaluate the performance in terms of data transmission rate. The results reveal that we have a remarkable data rate gain due to MIMO transmission and even more when this MIMO is equipped with beamforming capabilities. Copyright © 2014 John Wiley & Sons, Ltd.
Syntheses of Chiral Phosphazenes with Stereogenic Centers: NMR Behavior in the Presence of a Chiral Solvating Agent
Authors: Asmafiliz Nuran 
Published: January 2014

ABSTRACTThe condensation reactions of tetrachloro mono (1 and 2) and bisferrocenyl spirocyclotriphosphazenes (3–5) with morpholine in tetrahydrofuran gave the partly morpholino‐substituted ferrocenylphosphazenes. When the reactions were carried out with equal amounts of 1–5 and morpholine, the mono‐substituted ferrocenylphosphazenes (1a, 3a–5a) formed as the major product. While the reactions were made with 1 equiv of 1–5 and 2 equiv of morpholine, the corresponding geminal–phosphazenes (1b–5b) were isolated. In addition, the condensation reactions of 1 equiv of 1–5 and 3 equiv of morpholine resulted in the formation of di‐(1b–5b), tri‐(2c–5c), and tetra‐substituted phosphazenes. The tri‐substituted compounds were isolated as major products. Some new phosphazenes have stereogenic P center(s). The stereogenic properties of 1a and 2c were investigated using 31P nuclear magnetic resonance (NMR) spectroscopy in the presence of the chiral solvating agent; (S)‐(+)‐2,2,2‐trifluoro‐1‐(9′‐anthryl)ethanol. The structures of all the phosphazenes were characterized by one‐dimensional 1H, 13C, and 31P NMR, and two‐dimensional heteronuclear single quantum coherence spectral data. The salient spectral properties of the phosphazenes were presented.
Heterocyclic Aminoboron Compounds as Antituberculosis Agents
Authors: Campbell‐Verduyn Lachlan S. , Bowes Eric G. , Li Haoxin , Vallée Alain M. , Vogels Christopher M. , Decken Andreas , Gray Christopher A. , Westcott Stephen A. 
Published: January 2014

ABSTRACTWe have examined six boron compounds for their potential antituberculosis activities. Addition of 2‐formylphenyl pinacol boronate ester to tetraamine derivatives gave three new aminoboron compounds, which were elementally pure when obtained, and one example was characterized by a single crystal X‐ray diffraction study. Heterocyclic aminoboron compounds 1–4 showed moderate degrees of antimycobacterial activity against Mycobacterium tuberculosis.
The sirtuin class of histone deacetylases: Regulation and roles in lipid metabolism
Authors: Fiorino Erika , Giudici Marco , Ferrari Alessandra , Mitro Nico , Caruso Donatella , De Fabiani Emma , Crestani Maurizio 
Published: February 2014

AbstractAfter the completion of the human genome sequence and that from many other organisms, last decade has witnessed a spectacular gain of knowledge on gene functions. These studies provided new insights on the roles of genes in physiology and disease. Nonetheless, the availability of genetically modified models and of “omics” technologies such as next generation sequencing unveiled clear evidences on epigenetic regulation of many cellular functions. At this regard, sirtuins, belonging to class III histone deacetylase family, have emerged as regulators of metabolism as well as other cellular processes and seem ideally suited as targets of future therapeutical interventions. This review deals on general aspects of the biology of sirtuins and focuses on their relevance in lipid metabolism in different tissues, pointing to their exploitation as potential pharmacological targets of compounds that could be used as new therapeutic alternatives in several disorders ranging from type 2 diabetes and obesity to age‐related cardiovascular and neurodegenerative diseases. © 2014 IUBMB Life, 66(2):89–99, 2014
Zinc sulfide nanoparticles selectively induce cytotoxic and genotoxic effects on leukemic cells: involvement of reactive oxygen species and tumor necrosis factor alpha
Authors: Dash Sandeep Kumar , Ghosh Totan , Roy Soumyabrata , Chattopadhyay Sourav , Das Debasis 
Published: January 2014

ABSTRACTThe aim of the present study was to develop zinc sulfide nanoparticles (ZnS NPs) and to study their cytotoxicity against the KG‐1A (human acute myeloid leukemia) cell line. ZnS NPs were synthesized using the pyrolytic method and characterized by X‐ray diffraction, dynamic light scattering, surface zeta potential, scanning electron microscopy and atomic force microscopy. Cell viability study and flow cytometric analysis confirmed the potent cytotoxic effects of ZnS NPs on cancer cells in a dose‐dependent fashion. Successful uptakes of ZnS NPs by leukemic cells were confirmed by phase contrast fluorescence microscopy. pH‐dependent dissolution of ZnS NPs was done using atomic absorption microscopy to understand the cell‐specific internalization of Zn+. This internalization of NPs facilitated the generation of excess reactive oxygen species (ROS), followed by tumor necrosis factor alpha (TNF‐α) secretion which caused severe DNA damage as observed in the comet assay and altered the mitochondrial membrane potential (MMP) in leukemic cells. Surprisingly ZnS NPs had no toxic effects on normal lymphocytes at doses up to 50 µg ml–1. Pre‐treatment with ROS and TNF‐α inhibitor confirmed that these nanoparticles were able to kill leukemic cells by generating an excess amount of ROS and thereby initiated TNF‐α mediated apoptosis pathway. These findings clarify the mechanism with which ZnS NPs induced anticancer activities in vitro. To elicit its utilities and its application to cancer treatment in vivo is under investigation. Copyright © 2014 John Wiley &#38; Sons, Ltd.
Differential effect of methyl‐, butyl‐ and propylparaben and 17β‐estradiol on selected cell cycle and apoptosis gene and protein expression in MCF‐7 breast cancer cells and MCF‐10A non‐malignant cells
Authors: Wróbel Anna Maria , Gregoraszczuk Ewa Łucja 
Published: January 2014

ABSTRACTParabens are alkyl esters of p‐hydroxybenzoic acid used widely as antimicrobial preservatives in consumer products, including pharmaceuticals, foods and cosmetics. We showed previously that methyl‐, butyl‐ and propylparaben parabens, even at low doses, stimulate the proliferation of MCF‐7 breast cancer cells and non‐transformed MCF‐10A breast epithelial cells. The present study was undertaken to determine whether this represents a direct effect on cell cycle and apoptotic gene expression. MCF‐7 and MCF‐10A cells were exposed to methyl, butyl‐ and propylparaben (20 nm) or 17β‐estradiol (10 nm). Cell cycle and apoptotic gene expression were evaluated by real‐time polymerase chain reaction and protein expression by Western blot. 17β‐estradiol upregulated G1/S phase genes and downregulated cell cycle progression inhibitors in both MCF‐7 and MCF‐10A. Upregulation of Bcl‐xL and downregulation of caspase 9 was observed in MCF‐7, while upregulation of Bcl‐xL, BCL2L2 and caspase 9 was noted in MCF‐10A. Cyclins in MCF‐7 cells were not affected by any of the parabens. Methyl‐ and butylparaben had no effect on the expression of selected apoptotic genes in MCF‐7. In MCF‐10A, all parabens tested increased the expression of G1/S phase genes, and downregulated cell cycle inhibitors. Methylparaben increased pro‐survival gene. Butylparaben increased BCL2L1 gene, as did 17β‐estradiol, while propylparaben upregulated both the extrinsic and intrinsic apoptotic pathways. There are differences in cell cycle and apoptosis gene expression between parabens and 17β‐estradiol in MCF‐7 cells. In MCF‐10A cells, most of the genes activated by parabens were comparable to those activated by 17β‐estradiol. Copyright © 2014 John Wiley & Sons, Ltd.