bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of multiple measures of antiretroviral adherence in the Eastern European country of Georgia
Authors: Chkhartishvili Nikoloz , Rukhadze Nino , Svanidze Mariam , Sharvadze Lali , Dehovitz Jack A , Tsertsvadze Tengiz , McNutt Louise‐Anne , del Rio Carlos 
Published: April 2014

IntroductionThere is little information on adherence to antiretroviral therapy (ART) in the Eastern European region. This prospective study evaluated multiple measures of adherence and their association with viral suppression among HIV patients in Georgia.MethodsA prospective cohort study enrolled 100 consecutive antiretroviral‐naïve adult (age ≥18 years) patients, who were followed for three months. Adherence was assessed by medication refill and three self‐report measures (an AIDS Clinical Trial Group [ACTG] tool for four‐day adherence, a visual analogue scale [VAS] and a rating task for 30‐day adherence). The VAS represented a line anchored by 0 and 100% corresponding to the percentage of prescribed doses taken. The rating task asked patients to rate their ability to take all medications as prescribed, with responses categorized into six levels of adherence: very poor (0%), poor (20%), fair (40%), good (60%), very good (80%) and excellent (100%). Patients with adherence of ≥95% by medication refill, ACTG and VAS, and ≥80% by rating task, were defined as adherent.ResultsOf 100 patients enrolled, eight had missing data and were excluded from analysis. Among the remaining 92 patients, the median age was 39 years, and 70% were men. Major modes of HIV acquisition were injection drug use (IDU; 47.3%) and heterosexual contact (44.1%). The proportions of adherent patients were as follows: 68% by medication refill, 90% by ACTG questionnaire, 38% by VAS and 42% by rating task. On average, four months after commencing ART, 52 (56.5%) patients had a viral load <400 copies/ml and 26 (28.3%) patients had a viral load <50 copies/ml. Of 43 persons with a history of IDU, 22 (51.2%) reached a viral load of <400 copies/ml. In multivariate analysis, only refill adherence was a statistically significant predictor of viral suppression of <400 copies/ml: the risk ratio was 1.7 (95% CI: 1.1–2.8). Refill adherence, VAS and rating task were associated with viral suppression of <50 copies/ml. Non‐IDUs were twice as likely to achieve viral load <50 copies/ml compared to IDUs. Refill adherence had the largest area under the receiver‐operating characteristic curve for predicting viral suppression.ConclusionsMedication refill adherence was the strongest predictor of viral suppression. IDUs can achieve optimal virologic outcomes, but may require additional adherence support.
Incentives for methane mitigation and energy‐efficiency improvements in the case of Ukraine's natural gas transmission system
Authors: Roshchanka Volha , Evans Meredydd 
Published: April 2014

AbstractReducing methane losses is a concern for climate change policy and energy policy. The energy sector is the major source of anthropogenic methane emissions into the atmosphere in Ukraine. Reducing methane emissions and avoiding combustion can be very cost‐effective, but various barriers prevent such energy‐efficiency measures from taking place. To date, few examples of industry‐wide improvements exist. One example of substantial investments into upgrading natural gas transmission system comes from Ukraine's natural gas transmission company, Ukrtransgaz. The company's investments into system upgrades, along with a 34% fall in throughput, resulted in reduction of Ukrtransgaz system's own consumption of natural gas by 68% in 2011 compared to the level in 2005. Evaluating reductions in methane emissions is challenging because of lack of accurate data and gaps in accounting methodologies. At the same time, Ukraine's transmission system has undergone improvements that, at the very least, have contained methane emissions, if not substantially reduced them. In this paper, we describe recent developments in Ukraine's natural gas transmission system and analyze the incentives that forced the sector to pay close attention to its methane losses. Ukraine is one of the most energy‐intensive countries, among the largest natural gas consumers in the world, and a significant emitter of methane. The country is also dependent on imports of natural gas. A combination of several factors has created conditions for successful reductions in methane emissions and combustion. These factors include: an eightfold increase in the price of imported natural gas; comprehensive domestic environmental and energy policies, such as the Laws of Ukraine on Protecting the Natural Environment and on Air Protection; policies aimed at integration with European Union's energy market and accession to the Energy Community Treaty; and the country's participation in international cooperation on environment, such as through the Joint Implementation mechanism and the voluntary Global Methane Initiative. Learning about such case studies can help policymakers and sustainability professionals design better policies elsewhere.
The Minimized Power Geometric model: An analytical mixing model for calculating polyphase rock viscosities consistent with experimental data
Authors: Huet B. , Yamato P. , Grasemann B. 
Published: April 2014

AbstractHere we introduce the Minimized Power Geometric (MPG) model which predicts the viscosity of any polyphase rocks deformed during ductile flow. The volumetric fractions and power law parameters of the constituting phases are the only model inputs required. The model is based on a minimization of the mechanical power dissipated in the rock during deformation. In contrast to existing mixing models based on minimization, we use the Lagrange multipliers method and constraints of strain rate and stress geometric averaging. This allows us to determine analytical expressions for the polyphase rock viscosity, its power law parameters, and the partitioning of strain rate and stress between the phases. The power law bulk behavior is a consequence of our model and not an assumption. Comparison of model results with 15 published experimental data sets on two‐phase aggregates shows that the MPG model reproduces accurately both experimental viscosities and creep parameters, even where large viscosity contrasts are present. In detail, the ratio between experimental and MPG‐predicted viscosities averages 1.6. Deviations from the experimental values are likely to be due to microstructural processes (strain localization and coeval other deformation mechanisms) that are neglected by the model. Existing models that are not based on geometric averaging show a poorer fit with the experimental data. As long as the limitations of the mixing models are kept in mind, the MPG model offers great potential for applications in structural geology and numerical modeling.
Seismicity and structure in central Mexico: Evidence for a possible slab tear in the South Cocos plate
Authors: Dougherty Sara L. , Clayton Robert W. 
Published: April 2014

AbstractThe morphology of the transition from flat to normal subduction in eastern central Mexico is explored using intraslab earthquakes recorded by temporary and permanent regional seismic arrays. Observations of a sharp transition in slab dip near the abrupt end of the Trans‐Mexican Volcanic Belt (TMVB) suggest a possible slab tear located within the subducted South Cocos plate. The eastern lateral extent of a thin ultra‐slow velocity layer (USL) imaged atop the Cocos slab in recent studies along the Meso America Subduction Experiment array is examined here using additional data. We find an end to this USL which is coincident with the western boundary of a zone of decreased seismicity and the end of the TMVB near the sharp transition in slab dip. Waveform modeling of the 2‐D structure in this region using a finite difference algorithm provides constraints on the velocity and geometry of the slab's seismic structure and confirms the location of the USL. Analysis of intraslab seismicity patterns reveals clustering, sudden increase in depth, variable focal mechanism orientations and faulting types, and alignment of source mechanisms along the sharp transition in slab dip. The seismicity and structural evidence suggests a possible tear in the South Cocos slab. This potential tear, together with the tear along the Orozco Fracture Zone to the northwest, indicates a slab rollback mechanism in which separate slab segments move independently, allowing for mantle flow between the segments.
Sea salt as an ice core proxy for past sea ice extent: A process‐based model study
Authors: Levine J. G. , Yang X. , Jones A. E. , Wolff E. W. 
Published: April 2014

AbstractSea ice is a reflection of, and a feedback on, the Earth's climate. We explore here, using a global atmospheric chemistry‐transport model, the use of sea salt in Antarctic ice cores to obtain continuous long‐term, regionally integrated records of past sea ice extent, synchronous with ice core records of climate. The model includes the production, transport, and deposition of sea salt aerosol from the open ocean and “blowing snow” on sea ice. Under current climate conditions, we find that meteorology, not sea ice extent, is the dominant control on the atmospheric concentration of sea salt reaching coastal and continental Antarctic sites on interannual timescales. However, through a series of idealized sensitivity experiments, we demonstrate that sea salt has potential as a proxy for larger changes in sea ice extent (e.g., glacial‐interglacial). Treating much of the sea ice under glacial conditions as a source of salty blowing snow, we demonstrate that the increase in sea ice extent alone (without changing the meteorology) could drive, for instance, a 68% increase in atmospheric sea salt concentration at the site of the Dome C ice core, which exhibits an approximate twofold glacial increase in sea salt flux. We also show how the sensitivity of this potential proxy decreases toward glacial sea ice extent—the basis of an explanation previously proposed for the lag observed between changes in sea salt flux and δD (an ice core proxy for air temperature) at glacial terminations. The data thereby permit simultaneous changes in sea ice extent and climate.
Ruthenium‐Catalyzed Intramolecular Allylic Dearomatization/Migration Reaction of Indoles and Pyrroles
Authors: Yang Ze‐Peng , Zhuo Chun‐Xiang , You Shu‐Li 
Published: April 2014

AbstractAn efficient synthesis of polycyclic indole and pyrrole derivatives via a ruthenium‐catalyzed intramolecular allylic dearomatization/migration reaction has been developed. This method features wide substrate scope, mild reaction conditions, and an operationally simple procedure. The capture of the spiro intermediate provides solid evidence for the dearomatization/migration reaction pathway.magnified image
Enantioselective Cascade Oxa‐Michael–Michael Reactions of 2‐Hydroxynitrostyrenes with Enones Using a Prolinol Thioether Catalyst
Authors: Xia Ai‐Bao , Wu Chao , Wang Tao , Zhang Yan‐Peng , Du Xiao‐Hua , Zhong Ai‐Guo , Xu Dan‐Qian , Xu Zhen‐Yuan 
Published: April 2014

AbstractThe efficient simultaneous activation of cyclohexenones or simple alkyl acyclic enones and 2‐hydroxynitrostyrenes was realized by using a prolinol thioether catalyst. Thus, a highly chemo‐, diastereo‐ and enantioselective synthesis of functionalized tetrahydroxanthenones and chromanes with up to three contiguous stereocenters was developed.magnified image
Selective Palladium‐Catalyzed Direct CH Arylation of Unsubstituted N‐Protected Pyrazoles
Authors: Kumpulainen Esa T. T. , Pohjakallio Antti 
Published: April 2014

AbstractA highly selective C‐5 arylation of N‐dimethylaminosulfamoyl‐protected pyrazole with aryl bromides is catalyzed by 2–5 mol% palladium in the presence of triphenylphosphine ligand and carboxylic acid additive. Selectivities up to 45:1 (C‐5:C‐4) can be achieved by running the reaction in non‐polar solvents. A thorough study of scope and limitations shows good general tolerance of aryl bromide substitution. However, limitations on tolerance of ortho‐subsitution and protic functional groups were established. Together with a telescoped deprotection step this method presents a viable alternative for the synthesis of C‐3 arylated pyrazole building blocks.magnified image
Chiral Phosphoric Acid‐Catalyzed Enantioselective Three‐ Component Aza‐Diels–Alder Reactions of Aminopyrroles and Aminopyrazoles
Authors: Brioche Julien , Courant Thibaut , Alcaraz Lilian , Stocks Michael , Furber Mark , Zhu Jieping , Masson Géraldine 
Published: April 2014

AbstractA highly stereoselective three‐component Povarov reaction, catalyzed by (R)‐ and (S)‐BINOL hydrogen phosphate, was achieved for the first time with aminopyrroles and aminopyrazoles as 2‐azadiene precursors. A variety of aldehydes, enecarbamates, amino‐substituted azines participated in the reaction to afford the tetrahydropyrrolopyridines and tetrahydropyrazolopyridines in good yields with excellent diatereo‐ and enantioselectivities. A stereochemical model is proposed to account for the observed absolute stereochemistry.magnified image
Electrogenerated N‐Heterocyclic Carbene in Ionic Liquid: An Insight into the Mechanism of the Oxidative Esterification of Aromatic Aldehydes
Authors: Forte Gianpiero , Chiarotto Isabella , Inesi Achille , Loreto Maria Antonietta , Feroci Marta 
Published: April 2014

AbstractAn N‐heterocyclic carbene (NHC), generated by cathodic reduction of BMIm BF4, mediates the oxidative esterification of aromatic aldehydes with organic bromides in the corresponding ionic liquid as solvent. The product recovery by simple extractive work‐up with diethyl ether allowed the ionic liquid to be recycled up to 9 times for subsequent electrolyses, with no significant loss in the product yield. The isolation of an intermediate, whose structure was confirmed by synthesis and transformation into the ester, provided the key for a mechanistic insight into the reaction.magnified image
Regulated Incorporation of Two Different Metal Ions into Programmed Sites in a Duplex by DNA Polymerase Catalyzed Primer Extension
Authors: Funai Tatsuya , Nakamura Junko , Miyazaki Yuki , Kiriu Risa , Nakagawa Osamu , Wada Shun‐ichi , Ono Akira , Urata Hidehito 
Published: April 2014

AbstractMetal‐mediated base pairs formed by the coordination of metal ions to natural or artificial bases impart unique chemical and physical properties to nucleic acids and have attracted considerable interest in the field of nanodevices. AgI ions were found to mediate DNA polymerase catalyzed primer extension through the formation of a C–AgI–T base pair, as well as the previously reported C–AgI–A base pair. The comparative susceptibility of dNTPs to AgI‐mediated enzymatic incorporation into the site opposite cytosine in the template was shown to be dATP>dTTP≫dCTP. Furthermore, two kinds of metal ions, AgI and HgII, selectively mediate the incorporation of thymidine 5′‐triphosphate into sites opposite cytosine and thymine in the template, respectively. In other words, the regulated incorporation of different metal ions into programmed sites in the duplex by DNA polymerase was successfully achieved.
Doubling the Capacity of Lithium Manganese Oxide Spinel by a Flexible Skinny Graphitic Layer
Authors: Noh Hyun Kuk , Park Han‐Saem , Jeong Hu Young , Lee Sang Uck , Song Hyun‐Kon 
Published: April 2014

AbstractBy coating nanoparticular lithium manganese oxide (LMO) spinel with a few layers of graphitic basal planes, the capacity of the material reached up to 220 mA h g−1 at a cutoff voltage of 2.5 V. The graphitic layers 1) provided a facile electron‐transfer highway without hindering ion access and, more interestingly, 2) stabilized the structural distortion at the 3 V region reaction. The gain was won by a simple method in which microsized LMO was ball‐milled in the presence of graphite with high energy. Vibratory ball milling pulverized the LMO into the nanoscale, exfoliated graphite of less than 10 layers and combined them together with an extremely intimate contact. Ab initio calculations show that the intrinsically very low electrical conductivity of the tetragonal phase of the LMO is responsible for the poor electrochemical performance in the 3 V region and could be overcome by the graphitic skin strategy proposed.
Palladium‐Catalyzed C(sp3)H Activation: A Facile Method for the Synthesis of 3,4‐Dihydroquinolinone Derivatives
Authors: Yan Jia‐Xuan , Li Hu , Liu Xiang‐Wei , Shi Jiang‐Ling , Wang Xin , Shi Zhang‐Jie 
Published: April 2014

Abstract3,4‐Dihydroquinolinones were synthesized by the palladium‐catalyzed, oxidative‐addition‐initiated activation and arylation of inert C(sp3)H bonds. Pd(OAc)2 and P(o‐tol)3 were used as the catalyst and ligand, respectively, to improve the efficiency of the reaction. A further advantage of this reaction is that it could be performed in air. A relatively rare seven‐membered palladacycle was proposed as a key intermediate of the catalytic cycle.
Design of Monodisperse and Well‐Defined Polypeptide‐Based Polyvalent Inhibitors of Anthrax Toxin
Authors: Patke Sanket , Boggara Mohan , Maheshwari Ronak , Srivastava Sunit K. , Arha Manish , Douaisi Marc , Martin Jacob T. , Harvey Ian B. , Brier Matthew , Rosen Tania , Mogridge Jeremy , Kane Ravi S. 
Published: April 2014

AbstractThe design of polyvalent molecules, presenting multiple copies of a specific ligand, represents a promising strategy to inhibit pathogens and toxins. The ability to control independently the valency and the spacing between ligands would be valuable for elucidating structure–activity relationships and for designing potent polyvalent molecules. To that end, we designed monodisperse polypeptide‐based polyvalent inhibitors of anthrax toxin in which multiple copies of an inhibitory toxin‐binding peptide were separated by flexible peptide linkers. By tuning the valency and linker length, we designed polyvalent inhibitors that were over four orders of magnitude more potent than the corresponding monovalent ligands. This strategy for the rational design of monodisperse polyvalent molecules may not only be broadly applicable for the inhibition of toxins and pathogens, but also for controlling the nanoscale organization of cellular receptors to regulate signaling and the fate of stem cells.
Mechanistic Insights into Polycycle Formation by Reductive Cyclization in Ikarugamycin Biosynthesis
Authors: Zhang Guangtao , Zhang Wenjun , Zhang Qingbo , Shi Ting , Ma Liang , Zhu Yiguang , Li Sumei , Zhang Haibo , Zhao Yi‐Lei , Shi Rong , Zhang Changsheng 
Published: April 2014

AbstractIkarugamycin is a member of the polycyclic tetramate macrolactams (PTMs) family of natural products with diverse biological activities. The biochemical mechanisms for the formation of polycyclic ring systems in PTMs remain elusive. The enzymatic mechanism of constructing an inner five‐membered ring in ikarugamycin is reported. A three‐gene‐cassette ikaABC from the marine‐derived Streptomyces sp. ZJ306 is sufficient for conferring ikarugamycin production in a heterologous host. IkaC catalyzes a reductive cyclization reaction to form the inner five‐membered ring by a Michael addition‐like reaction. This study provides the first biochemical evidence for polycycle formation in PTMs and suggests a reductive cyclization strategy which may be potentially applicable in general to the corresponding ring formation in other PTMs.
Biocompatible and biodegradable alginate/poly(N‐isopropylacrylamide) hydrogels for sustained theophylline release
Authors: Dumitriu Raluca Petronela , Oprea Ana‐Maria , Natalia Cheaburu Catalina , Nistor Manuela‐Tatiana , Novac Ovidiu , Ghiciuc Cristina Mihaela , Profire Lenuta , Vasile Cornelia 
Published: April 2014

ABSTRACTMixed‐interpenetrated polymeric networks based on sodium alginate (ALG) and poly(N‐isopropylacryl amide) (PNIPAAm) covalently cross‐linked with N,N'‐methylenebisacrylamide are studied for their biocompatibility, nontoxicity, and biodegradability aiming their application in drug delivery. The presence of drug‐polymeric matrix interactions and the distribution of the drug in the polymeric network for theophylline‐loaded ALG/PNIPAAm hydrogels are also investigated by spectroscopic and microscopic methods. The quantitative evaluation of theophylline loaded hydrogels performed by NIR‐CI technique shows a better drug entrapment and a higher homogeneity of the samples with increased alginate content. The thermal behavior of the hydrogels is significantly modified by theophylline presence. The application of the ALG/PNIPAAm hydrogels as carriers for sustained drug release formulations was assessed by the theophylline release tests performed both by in vitro and in vivo studies. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40733.
Peripheral Calcitonin Gene‐Related Peptide Receptor Activation and Mechanical Sensitization of the Joint in Rat Models of Osteoarthritis Pain
Authors: Bullock Craig M. , Wookey Peter , Bennett Andrew , Mobasheri Ali , Dickerson Ian , Kelly Sara 
Published: April 2014

ObjectiveTo investigate the role of the sensory neuropeptide calcitonin gene‐related peptide (CGRP) in peripheral sensitization in experimental models of osteoarthritis (OA) pain.MethodsExperimental knee OA was induced in rats by intraarticular injection of monosodium iodoacetate (MIA) or by transection of the medial meniscus (MMT). Single‐unit recordings of joint‐innervating nociceptors were obtained in MIA‐ and saline‐treated rats following administration of CGRP or the CGRP receptor antagonist CGRP 8–37. Effects of CGRP 8–37 were also examined in rats that underwent MMT and sham operations. Protein and messenger RNA (mRNA) levels of CGRP receptor components in the L3–L4 dorsal root ganglion (DRG) were investigated following MIA treatment.ResultsIn both the MIA and MMT groups, the mechanical sensitivity of joint nociceptors was enhanced compared to that in the control groups. Exogenous CGRP increased mechanical sensitivity in a greater proportion of joint nociceptors in the MIA‐treated rats than in the saline‐treated rats. Local blockade of endogenous CGRP by CGRP 8–37 reversed both the MIA‐ and MMT‐induced enhancement of joint nociceptor responses. Joint afferent cell bodies coexpressed the receptor for CGRP, called the calcitonin‐like receptor (CLR), and the intracellular accessory CGRP receptor component protein. MIA treatment increased the levels of mRNA for CLR in the L3–L4 DRG and the levels of CLR protein in medium and large joint afferent neurons.ConclusionOur findings provide new and compelling evidence implicating a role of CGRP in peripheral sensitization in experimental OA. Our novel finding of CGRP‐mediated control of joint nociceptor mechanosensitivity suggests that the CGRP receptor system may be an important target for the modulation of pain during OA. CGRP receptor antagonists recently developed for migraine pain should be investigated for their efficacy against pain in OA.