bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electron Spin Resonance Spectroscopy
Authors: Chiesa Mario , Giamello Elio 
Published: January 2014

Electron spin resonance (ESR) or electron paramagnetic resonance (EPR) spectroscopy is an experimental technique for detecting and characterizing chemical systems bearing one or more unpaired electrons. The application of the technique, the background of which is similar to the more diffused nuclear magnetic resonance (NMR) spectroscopy, therefore concerns (i) organic and inorganic free radicals; (ii) trapped radicals in various matrices, including irradiated solids (radiation chemistry), frozen inert matrices, and solid surfaces; (iii) transition metal ion compounds in classical inorganic systems or in biological systems; (iv) excited paramagnetic states (triplets) and several other systems of relevant scientific interest. The aim of this article is to provide an overall survey on the basic principles and on the various applications of the technique. This is done by describing, first, the physical basis of the electron resonance phenomenon (microwave absorption when the system is in the line of force of a strong external magnetic field) and, subsequently, the main types of interactions that the unpaired electron undergoes in the chemical system to which it belongs and which determines the features of the experimental spectra. These are essentially (i) the magnetic interaction of the electron with nuclei of nonzero nuclear spin (hyperfine interaction), which determines the multiline structure of the spectrum (hyperfine structure) and (ii) the interaction of the electron spin with the electron orbital angular momentum, occurring through the so‐called spin–orbit coupling. This latter interaction causes the dependence of the resonance on the orientation of the radical in the external magnetic field. Particular emphasis will be given to the different types of spectra observed according to the physical state of the investigated sample (liquid solutions, single solid crystals, or microcrystalline‐powdered solids). In the last case (powders), the essential methodology for understanding the often complex profiles of the experimental spectra is described. Advanced electron resonance techniques, essentially ENDOR (electron–nuclear double resonance) and pulse EPR, will also be briefly mentioned.The final part of this article is devoted to some analytical applications of the technique, including spin trapping (an essential tool for the detection and quantitative evaluation of reactive short‐lived radicals), radiation dosimetry (with applications to medical problems and irradiated foodstuff analysis), and dating of geologically relevant systems.
A General and Practical Palladium‐Catalyzed Direct α‐Arylation of Amides with Aryl Halides
Authors: Zheng Bing , Jia Tiezheng , Walsh Patrick J. 
Published: January 2014

AbstractAn efficient system for the direct catalytic intermolecular α‐arylation of acetamide derivatives with aryl bromides and chlorides is presented. The palladium catalyst is supported by Kwong’s indole‐based phosphine ligand and provides monoarylated amides in up to 95% yield. Excellent chemoselectivities (>10:1) in the mono‐ and diarylation with aryl bromides were achieved by careful selection of bases, solvents, and stoichiometry. Under the coupling conditions, the weakly acidic α‐protons of amides (pKa up to 35) were reversibly depotonated by lithium tert‐butoxide (LiO‐t‐Bu), sodium tert‐butoxide (NaO‐t‐Bu) or sodium bis(trimethylsilyl)amide [NaN(SiMe3)2].magnified image
Assessing Changes in Dairy Product Import Demand: The Case of South Korea with Implementation of the KORUS FTA
Authors: Jones Kiethly G. , Blayney Don 
Published: January 2014

ABSTRACTThe impacts of implementing the Korea‐U.S. Free Trade Agreement (KORUS FTA) on South Korea's dairy trade are assessed in this study based on empirical estimates of short‐run and long‐run source‐based import demand parameters for three major imported dairy products. These estimates were derived using the Central Bureau of Statistics (CBS) demand system model. The impacts of the tariff reductions associated with the KORUS FTA were calculated. The results suggest that the KORUS FTA will open South Korean dairy product markets primarily by reducing import prices of international suppliers’ products. The altered import relationships among those suppliers raises overall dairy product imports into South Korea. [EconLit Classifications: F14, Q17].
Methylglyoxal‐augmented manuka honey as a topical anti–Staphylococcus aureus biofilm agent: safety and efficacy in an in vivo model
Authors: Paramasivan Sathish , Drilling Amanda Jane , Jardeleza Camille , Jervis‐Bardy Josh , Vreugde Sarah , Wormald Peter John 
Published: January 2014

BackgroundBacterial biofilms are thought to contribute to recalcitrance in chronic rhinosinusitis (CRS) patients. Manuka honey (MH) and its active component methylglyoxal (MGO) have demonstrated antibiofilm activity in vitro. This study evaluated the safety and efficacy of these agents in an in vivo model.MethodsTo assess safety, ovine frontal sinuses were flushed twice daily for 14 days. In each sheep, 1 sinus was flushed with a panel of MGO concentrations ranging from 0.5 to 7.2 mg/mL alone and flushed with a panel of with 16.5% wt/vol MH enriched with MGO at the same range of concentrations (0.5–7.2 mg/mL; designated MH/MGO). Contralateral sinuses were flushed with saline control. Tissue morphology was assessed histologically and with scanning electron microscopy. Efficacy was tested by developing Staphylococcus aureus biofilms in sheep sinuses. Twice‐daily irrigation for 5 days was commenced with either saline, MGO (0.5–3.6 mg/mL) alone, or MH/MGO (with 0.5–3.6 mg/mL MGO). Biofilm biomass was compared between the groups (n = 4) using LIVE/DEAD BacLight staining and confocal scanning laser microscopy.ResultsThe results of the safety assessment, for normal sinuses treated with MGO alone or with MH/MGO (≤1.8 mg/mL) showed normal pseudostratified epithelium and cilia structure; however, higher concentrations caused cilia denudation and squamous metaplasia. As for efficacy, when compared to saline flush, treatment with MH/MGO at 0.9 mg/mL (0.608 ± 0.110 vs 0.316 ± 0.197 μm3/μm2, respectively; p = 0.015) and 1.8 mg/mL (0.676 ± 0.079 vs 0.114 ± 0.033 μm3/μm2, respectively; p = 0.001) significantly reduced biofilm biomass.ConclusionSinus irrigation with MH/MGO at MGO concentrations between 0.9 and 1.8 mg/mL is both safe to mucosa and efficacious against S. aureus biofilm. MH/MGO irrigation could represent a viable treatment option for recalcitrant CRS.
Factors associated with early progression of non‐small‐cell lung cancer treated by epidermal growth factor receptor tyrosine‐kinase inhibitors
Authors: Rozensztajn Nathalie , Ruppert Anne‐Marie , Lavole Armelle , Giroux Leprieur Etienne , Duruisseaux Michael , Vieira Thibault , Rabbe Nathalie , Lacave Roger , Antoine Martine , Cadranel Jacques , Wislez Marie 
Published: January 2014

AbstractEpidermal growth factor receptor tyrosine‐kinase inhibitors (EGFR‐TKI) are a therapeutic option as second‐line therapy in non‐small‐cell lung carcinoma (NSCLC), regardless of the EGFR gene status. Identifying patients with early progression during EGFR‐TKI treatment will help clinicians to choose the best regimen, TKI or chemotherapy. From a prospective database, all patients treated with gefitinib or erlotinib between 2001 and 2010 were retrospectively reviewed. Patients were classified into two groups according to their tumor response by RECIST after 45 days of treatment, progressive disease (PD) or controlled disease (CD). Two hundred and sixty‐eight patients were treated with EGFR‐TKI, among whom 239 were classified as PD (n = 75) and CD (n = 164). Median overall survival was 77 days (95% CI 61–109) for PD and 385 days (95% CI 267–481) for CD. Patients with PD were of younger age (P = 0.004) and more frequently current smokers (P = 0.001) had more frequently a performance status ≥2 (P = 0.012), a weight loss ≥10% (P = 0.025), a shorter time since diagnosis (P < 0.0001), a pathological classification as non‐otherwise‐specified NSCLC (P = 0.01), and the presence of abdominal metastases (P = 0.008). In multivariate analysis, abdominal metastases were the only factor associated with early progression (odds ratio (OR) 2.17, 95% CI [1.12–4.19]; P = 0.021). Wild‐type EGFR versus mutated EGFR was associated with early progression. The presence of abdominal metastasis was independently associated with early progression in metastatic NSCLC receiving EGFR‐TKI.
Luminescent Mechanochromic Porous Coordination Polymers
Authors: Wen Tian , Zhou Xiao‐Ping , Zhang De‐Xiang , Li Dan 
Published: January 2014

AbstractThree 2D luminescent isomeric porous coordination polymers are synthesized and characterized. Their luminescence properties can be modified by grinding and they can act as mechanochromic materials and their properties are probably related to the weak interactions of cuprophilicity and π–π interactions.
Stage‐specific associations between beta blocker use and prognosis after colorectal cancer
Authors: Jansen Lina , Hoffmeister Michael , Arndt Volker , Chang‐Claude Jenny , Brenner Hermann 
Published: January 2014

BACKGROUNDRecent observational studies have suggested that the use of beta blockers might be associated with better prognosis after cancer. Because evidence is limited for colorectal cancer (CRC), the association of beta blocker use and prognosis was investigated in a large population‐based cohort of patients with CRC.METHODSBetween 2003 and 2007, information on beta blocker use at diagnosis and potential confounders was collected by personal interviews for 1975 patients with CRC. Vital status, cause of death, and recurrence status were assessed during a median follow‐up time of 5.0 years. The associations of beta blocker use and overall, CRC‐specific, and recurrence‐free survival were estimated by Cox proportional hazard regression. In addition, beta blocker subgroup, site, and stage‐specific analyses were performed.RESULTSAfter adjustment for covariates including sociodemographic, cancer‐related, and lifestyle factors and comorbidity and medications, no significant association between beta blocker use at diagnosis and prognosis was observed for all stages combined. However, in stage‐specific analyses, beta blocker use was associated with longer overall survival (hazard ratio = 0.50; 95% confidence interval = 0.33‐0.78) and CRC‐specific survival (hazard ratio = 0.47; 95% confidence interval = 0.30‐0.75) in stage IV patients. For these patients, median overall survival was 18 months longer and CRC–specific survival was 17 months longer for beta blocker users than for nonusers (38 versus 20 months and 37 versus 20 months, respectively).CONCLUSIONSThese results suggest that beta blocker use might be associated with longer survival in patients with stage IV CRC. Cancer 2014;120:1178–1186. © 2014 American Cancer Society.
MTL‐based implementation of current‐mode CMOS RMS‐to‐DC converters
Authors: Shaterian Mostafa , Twigg Christopher M. , Azhari Javad 
Published: January 2014

SummaryIn this paper, systematic implementation of current‐mode RMS‐to‐DC converters based upon MOS translinear (MTL) principle, utilizing symmetric cascoded MTL cell (SCMC) is proposed. Theory of operation and mathematical analysis of both explicit (direct) and implicit (indirect) techniques for realization of SCMC‐based RMS‐to‐DC converters are discussed. The SCMC includes a folded MTL loop and realizes an MTL equation. MTL principle utilizes the square law characteristics of saturated MOS transistors to realize square‐root domain (SRD) functions. The SCMC is constructed by two connected cascoded current mirrors and has a compact, symmetric, and multi‐purpose structure, with capability of implementing the circuits into the programmable and configurable structures. The proposed RMS‐to‐DC converters utilize the SCMC along with a configurable current mirror array. The required squaring and square‐rooting functions are realized using the SCMC, after proper configuration of the current mirror array. The proposed circuits have been implemented using a reconfigurable architecture fabricated in a 0.5 µm CMOS technology. Copyright © 2014 John Wiley & Sons, Ltd.
Endoreduplicative standards for calibration of flow cytometric C‐Value measurements
Authors: Galbraith David W. 
Published: January 2014

AbstractIt has been estimated that there are, globally, as many as 400,000 species of the angiosperms (the flowering plants). Of these, a minimal proportion has been characterized at the cytological level. Urgency is required in initiating a systematic and comprehensive census, due to species extinction as a consequence of anthropogenic activities. Fundamental to eukaryotes is the 2C‐value, the amount of DNA contained within the nucleus of the unreduced gametes. Flow cytometry provides an ideal method for determining C‐values, but the values archived in the Kew Plant C‐value Database represent <2% of these species. Complicating the issue is a proliferation of different, and inconsistent standards for C‐value measurements utilizing flow cytometry, and variability associated with different instrument platforms and using different staining procedures. In previous work, the use of flow cytometry for analysis of plant nuclear DNA contents for species spanning much of the range of genome sizes found in the angiosperms was described. For this work, an endoreduplicative species (Arabidopsis thaliana L.) was particularly helpful as an internal standard for genome size calibration. Such a standard is compromised if it overlaps in DNA content than that of the species whose genome size is sought. This report describes the use of a second species displaying endoreduplication, Capsicum annuum L., for similar standardization. The results (a) indicate accurate reporting of nuclear DNA contents across a range 0.32–423.68 pg, (b) confirm that endoreduplication increases nuclear DNA contents by complete replication of the genome, and (c) provide a means for quality control of linearity in instrumentation over defined dynamic ranges. © 2014 International Society for Advancement of Cytometry
Profit‐based exclusive‐or coding algorithm for data retransmission in DVB‐H with a recovery network
Authors: Wang You‐Chiun 
Published: January 2014

SummaryThe digital video broadcasting‐handheld (DVB‐H) standard is developed by European Telecommunications Standards Institute to broadcast digital videos to handheld devices, but data loss is a critical issue due to the broadcast behavior. On the other hand, DVB‐Internet protocol datacasting (DVB‐IPDC) integrates DVB‐H with an Internet protocol‐based wireless network to provide bidirectional communication. We adopt this wireless network to deal with data retransmission and call it a recovery network. The paper argues that network coding can improve retransmission efficiency of the recovery network because DVB‐H packet loss often exhibits high correlation. In addition, DVB‐H packets may be heterogeneous in the sense that they have different importance. According to these two arguments, the paper considers that DVB‐H packets are associated with different profit depending on their importance and proposes an α‐maximum profit network coding problem. It asks the base station in the recovery network to use no more than α coded packets for handheld devices to retrieve the lost DVB‐H packets such that the overall profit is the maximum. An efficient exclusive‐or coding scheme, namely the profit‐based exclusive‐or network coding (PEN) algorithm, is proposed to solve this problem. Extensive simulation results also verify the effectiveness of the PEN algorithm. Copyright © 2014 John Wiley & Sons, Ltd.
Tosylhydrazide‐Promoted Diastereoselective Intramolecular 1,3‐Dipolar Cycloadditions: Synthesis of Tetrahydropyrrolo[3,4‐c]pyrazoles
Authors: Barroso Raquel , Escribano Maria , Cabal Maria‐Paz , Valdés Carlos 
Published: January 2014

AbstractA very straightforward diastereoselective synthesis of tetrahydropyrrolo[3,4‐c]pyrazoles by intramolecular 1,3‐dipolar cycloaddition is described. The starting materials for the synthetic route are N‐Boc‐protected α‐amino acids, which are first transformed into N‐allyl‐α‐amino ketones through conventional methodologies. Then, a one‐pot sequence that involves formation of a tosylhydrazone from the ketone, base‐induced decomposition of the hydrazone, and intramolecular 1,3‐dipolar cycloaddition of the diazo compound generated, gives rise to the bicyclic systems with total diastereoselectivity and high preservation of the enantiomeric purity. However, the analogous process employing α‐amino aldehydes lacks stereoselectivity. DFT computational modeling has been carried out to account for the different behavior of the two types of systems.
The isolated carboxy‐terminal domain of human mitochondrial leucyl‐tRNA synthetase rescues the pathological phenotype of mitochondrial tRNA mutations in human cells
Authors: Perli Elena , Giordano Carla , Pisano Annalinda , Montanari Arianna , Campese Antonio F , Reyes Aurelio , Ghezzi Daniele , Nasca Alessia , Tuppen Helen A , Orlandi Maurizia , Di Micco Patrizio , Poser Elena , Taylor Robert W , Colotti Gianni , Francisci Silvia , Morea Veronica , Frontali Laura , Zeviani Massimo , d'Amati Giulia 
Published: January 2014

AbstractMitochondrial (mt) diseases are multisystem disorders due to mutations in nuclear or mtDNA genes. Among the latter, more than 50% are located in transfer RNA (tRNA) genes and are responsible for a wide range of syndromes, for which no effective treatment is available at present. We show that three human mt aminoacyl‐tRNA syntethases, namely leucyl‐, valyl‐, and isoleucyl‐tRNA synthetase are able to improve both viability and bioenergetic proficiency of human transmitochondrial cybrid cells carrying pathogenic mutations in the mt‐tRNAIle gene. Importantly, we further demonstrate that the carboxy‐terminal domain of human mt leucyl‐tRNA synthetase is both necessary and sufficient to improve the pathologic phenotype associated either with these “mild” mutations or with the “severe” m.3243A>G mutation in the mt‐tRNALeu(UUR) gene. Furthermore, we provide evidence that this small, non‐catalytic domain is able to directly and specifically interact in vitro with human mt‐tRNALeu(UUR) with high affinity and stability and, with lower affinity, with mt‐tRNAIle. Taken together, our results sustain the hypothesis that the carboxy‐terminal domain of human mt leucyl‐tRNA synthetase can be used to correct mt dysfunctions caused by mt‐tRNA mutations.
Evaluation of the WEPP model and digital elevation grid size, for simulation of streamflow and sediment yield in a heterogeneous catchment
Authors: Pieri Linda , Poggio Matteo , Vignudelli Marco , Bittelli Marco 
Published: January 2014

ABSTRACTThe paper presents the result of an application of the GeoWEPP model in a heterogeneous semi‐agricultural catchment located in the northern Italian Apennines mountain range. The objectives were: (a) to evaluate the GeoWEPP model in a heterogeneous catchment in a Mediterranean climate and (b) to examine the effect of digital elevation model grid size on hydrological and sediment yield simulations. The catchment is characterized by large heterogeneity in geology, soil type, vegetation cover and topography. In addition, 10% of its area is occupied by calanchi (badlands), characterized by steep, bare soil and accentuated erosion. Experimental streamflow data were compared with those simulated by GeoWEPP for a period of eight years and the results were evaluated by means of statistical indices, with the analysis of the flow duration curve. Simulated sediment yields were compared with experimental data for one year. The streamflow cumulative annual results were satisfactory with NSE oscillating between 0.40 and 0.83 and RMSE between 1.1 and 2.9 mm. Also, the performance of the model with daily streamflow data was positive (NSE = 0.68 and RMSE = 1.9 mm). The flow duration curve indicated that GeoWEPP could represent the experimental streamflow for fluxes over 1 mm d−1. The model performance for simulation of sediment yield was satisfactory with both digital elevation models of different grid sizes (NSE = 0.84 and 0.87). Indeed, the sensitivity analysis tests of the model showed that there was no statistically significant improvement in the accuracy of the digital elevation model between 10 and 2 m resolution. These results were confirmed for both streamflow as well as sediment yield. Additional sensitivity analysis of other model parameters performed on the entire catchment and badlands hillslopes showed that bedrock hydraulic conductivity primarily affected the model in both settings. Copyright © 2014 John Wiley & Sons, Ltd.
Kinetic analysis of endothermic degradation of magnesium hydroxide, calcium hydroxide and calcium carbonate in the context of passive fire protection
Authors: Ciudad Aleix , Haurie Laia , Lacasta A. M. 
Published: January 2014

SummaryIn a fire scenario, huge amounts of heat are generated and high temperatures rapidly achieved in such a way that the integrity of structural materials becomes compromised. One of the aims of passive fire protection is the use of building materials that are able to absorb at least part of that heat and maintain the structural materials under critical temperatures for longer times in order to gain evacuation time. Gypsum panels are commonly used in building walls, but they only absorb heat at temperatures around 110 °C. We use three inorganic fillers, Mg(OH)2, Ca(OH)2 and CaCO3, which undergo endothermic transitions at high temperatures to obtain an improved panel with a richer heat‐absorbing profile. With this formulation, the time to reach temperatures of the order of 500 °C, critical for steel and reinforced concrete, is significantly increased. In this work, we focus on the kinetics of the endothermic fillers as an essential ingredient for further spatially extended simulations that include macroscopic heat and mass transfer phenomena or sample heterogeneities. However, kinetics may be affected as well by heat transfer effects that occur at molecular levels. Copyright © 2014 John Wiley & Sons, Ltd.
Recent Advances in Thiol and Sulfide Reactive Probes
Authors: Wang Ke , Peng Hanjing , Wang Binghe 
Published: January 2014

ABSTRACTBecause of the biological relevance of thiols and sulfides such as cysteine, homocysteine, glutathione and hydrogen sulfide, their detection has attracted a great deal of research interest. Fluorescent probes are emerging as a new strategy for thiol and hydrogen sulfide analysis due to their high sensitivity, low cost, and ability to detect and image thiols in biological samples. In this short review, we have summarized recent advances in the development of thiol and hydrogen sulfide reactive fluorescent probes. These probes are compared and contrasted with regard to their designing strategies, mechanisms, photophysical properties, and/or reaction kinetics. Biological applications of these probes are also discussed. J. Cell. Biochem. 115: 1007–1022, 2014. © 2013 Wiley Periodicals, Inc.