bluuebunny/crossref_metadata_2025_split huggingface dataset:
PhaseLift: Exact and Stable Signal Recovery from Magnitude Measurements via Convex Programming
Authors: Candès Emmanuel J. , Strohmer Thomas , Voroninski Vladislav 
Published: November 2012

AbstractSuppose we wish to recover a signal
\input amssym $\font\abc=cmmib10\def\bi#1{\hbox{\abc#1}} {\bi x} \in {\Bbb C}^n$
from m intensity measurements of the form $\font\abc=cmmib10\def\bi#1{\hbox{\abc#1}} |\langle \bi x,\bi z_i \rangle|^2$, $i = 1, 2, \ldots, m$; that is, from data in which phase information is missing. We prove that if the vectors $\font\abc=cmmib10\def\bi#1{\hbox{\abc#1}}{\bi z}_i$
are sampled independently and uniformly at random on the unit sphere, then the signal x can be recovered exactly (up to a global phase factor) by solving a convenient semidefinite program–‐a trace‐norm minimization problem; this holds with large probability provided that m is on the order of $n {\log n}$, and without any assumption about the signal whatsoever. This novel result demonstrates that in some instances, the combinatorial phase retrieval problem can be solved by convex programming techniques. Finally, we also prove that our methodology is robust vis‐à‐vis additive noise. © 2012 Wiley Periodicals, Inc.
The Templating Effect and Photochemistry of Viologens in Halometalate Hybrid Crystals
Authors: Mercier Nicolas 
Published: November 2012

AbstractAlthough the chemistry of viologens in solution has been thoroughly investigated, their intriguing functions in the crystalline state have been the subject of less attention. Recently, many hybrid structures incorporating viologen cations have been published, and a considerable number of them possess interesting properties in the solid state. Elaborate examination of these structures has indicated that peculiar interactions between the viologen dication and anions, including side contacts and face contacts, are very often encountered. This suggests that the viologen dications have a great influence on their surroundings at the atomic level. This remarkable templating effect is well demonstrated by a series of hybrids, in which the rare MX5 (M = BiIII, SbIII; X = Cl, Br, I) inorganic chain of trans‐connected octahedra is stabilised by a methylviologen dication; this leads to a new fascinating family of ferroelectrics. In contrast, owing to their unique structural features, viologen dications exhibit prominent photochemistry. Upon irradiation, viologen dications (V2+), with good electron‐accepting abilities, are able to accept one electron from an electron donor, either an anion or a molecule, to afford stable separated charge state systems with photochromic properties resulting from the coloured V·+ radicals. This process takes place in the crystalline solid state and offers great opportunities to understand their structure–property relationships. The relationships discovered in the current system will guide subsequent rational syntheses to optimise the properties of the materials.
Synthesis of Symmetrical Dinitro‐ and Diamino‐Substituted Tröger's Base Analogues
Authors: Šturala Jiří , Cibulka Radek 
Published: November 2012

AbstractThis report describes a new synthetic approach to symmetrical diamino‐substituted Tröger's base analogues, allowing the synthesis of 1,7‐, and 4,10‐diamino derivatives with no additional substituents and of 3,9‐diamino derivative with methyl groups in the 1‐, 4‐, 7‐ and 10‐positions. The synthesis uses regioselective nitration of dihalo‐substituted‐ or tetrahalo‐substituted Tröger's bases followed either by hydrogenation of the nitro functions accompanied by removal of halogen atoms or alternatively by chemoselective reduction of nitro groups to obtain the dihalo‐diamino‐substituted Tröger's base analogues. The 2,8‐diamino derivatives, not accessible by this approach, can be prepared by Buchwald–Hartwig amination of the 2,8‐dibromo‐substituted Tröger's bases.
Iron‐Catalyzed Diastereoselective Synthesis of α‐(Methoxycarbonyl)allylsilanes
Authors: Chai Guobi , Zeng Rong , Fu Chunling , Ma Shengming 
Published: November 2012

AbstractStereodefined polysubstituted α‐(methoxycarbonyl)allylsilanes were synthesized through iron‐catalyzed conjugate additions between 1‐(trimethylsilyl)allene‐1‐carboxylates and Grignard reagents in good to excellent yields. The use of Et2O as solvent for Grignard reagents was found to be very important for the diastereoselectivity of the reaction. Applications of the prepared allylic silanes for the stereocontrolled synthesis of α,β‐alkenoates, a β,γ‐alkenoate, and an allylic fluoride have been demonstrated.
Synthesis and Characterization of Oxyanion‐Doped Cobalt Containing Perovskites
Authors: Porras‐Vazquez Jose M. , Slater Peter R. 
Published: November 2012

AbstractIn this paper, we report the incorporation of borate, silicate and phosphate into La0.6Sr0.4Co0.8Fe0.2O3–δ (LSCF) and Sr0.9Y0.1CoO3–δ (SYC) cathode materials for solid oxide fuel cells (SOFCs). In the former, an increase in the electronic conductivity was observed, which can be correlated with electron doping due to the oxyanion doping favoring the introduction of oxide ion vacancies. The highest conductivity was observed for La0.6Sr0.4Co0.76Fe0.19B0.05O3–δ, 1190 S cm–1 at 700 °C, in comparison with 431 S cm–1 for undoped La0.6Sr0.4Co0.8Fe0.2O3–δ at the same temperature. For Sr0.9Y0.1CoO3–δ series the conductivity suffers a decrease on doping, attributed to any effect of electron doping being outweighed by the effect of partial disruption of the electronic conduction pathways by the oxyanion. Composites of these cathode materials with 50% CGO10 were examined on dense CGO10 pellets and the area‐specific resistances (ASR) in symmetrical cells were determined. The ASR values, at 800 °C, were 0.20, 0.08 and 0.11 Ω cm2 for La0.6Sr0.4Co0.8Fe0.2O3–δ, La0.6Sr0.4Co0.76Fe0.19B0.05O3–δ and La0.6Sr0.4Co0.78Fe0.195Si0.025O3–δ, respectively. For the SYC materials, the oxyanion‐doped compositions also showed an improvement in the ASR values with respect to the parent compounds, despite the lower electronic conductivity in these cases. This observation may be due to an increase in ionic conductivity due to oxyanion incorporation leading to the formation of oxide ion vacancies. In addition, the stability of these systems towards CO2 was studied. For La0.6Sr0.4Co0.8(1–x)Fe0.2(1–x)MxO3–δ series, all compositions showed no evidence for reactivity with CO2 between RT and 1000 °C. On the other hand, for the Sr0.9Y0.1Co1–xMxO3–δ series, some reactivity was observed, although the CO2 stability was shown to be improved on oxyanion doping. Thus, these results show that oxyanion doping can have a beneficial effect on the performance of perovskite cobaltite cathode materials.
Transient acidification and subsequent proinflammatory cytokine stimulation of astrocytes induce distinct activation phenotypes
Authors: Renner Nicole A. , Sansing Hope A. , Inglis Fiona M. , Mehra Smriti , Kaushal Deepak , Lackner Andrew A. , MacLean Andrew G. 
Published: November 2012

AbstractThe foot processes of astrocytes cover over 60% of the surface of brain microvascular endothelial cells, regulating tight junction integrity. Retraction of astrocyte foot processes has been postulated to be a key mechanism in pathology. Therefore, movement of an astrocyte in response to a proinflammatory cytokine or even limited retraction of processes would result in leaky junctions between endothelial cells. Astrocytes lie at the gateway to the CNS and are instrumental in controlling leukocyte entry. Cultured astrocytes typically have a polygonal morphology until stimulated. We hypothesized that cultured astrocytes which were induced to stellate would have an activated phenotype compared with polygonal cells. We investigated the activation of astrocytes derived from adult macaques to the cytokine TNF‐α under resting and stellated conditions by four parameters: morphology, intermediate filament expression, adhesion, and cytokine secretion. Astrocytes were stellated following transient acidification; resulting in increased expression of GFAP and vimentin. Stellation was accompanied by decreased adhesion that could be recovered with proinflammatory cytokine treatment. Surprisingly, there was decreased secretion of proinflammatory cytokines by stellated astrocytes compared with polygonal cells. These results suggest that astrocytes are capable of multiple phenotypes depending on the stimulus and the order stimuli are applied. J. Cell. Physiol. 228: 1284–1294, 2013. © 2012 Wiley Periodicals, Inc.
MRT letter: Localization of endogenous hydrogen peroxide by modified processes of sample preparation for transmissionelectron microscope in Escherichia coli
Authors: Li Xin , Hu Rongliu , Zhu Wenxue , Fan Jinling , Pang Xinyue , Wang Na , Wang Liping , Yang Lipeng , Zhao Chunyan , He Chenyang 
Published: November 2012

AbstractThe bacterial endogenous hydrogen peroxide (H2O2) was detected cytochemically by its reaction with cerium chloride (CeCl3) to produce electron‐dense deposits of cerium perhydroxides. The sequence of fixation and CeCl3 staining of H2O2 in the processing of transmission electron microscope (TEM) sample preparation is crucial to the localization of endogenous H2O2 in Escherichia coli. In this study, results confirmed that the process that fixation simultaneously with CeCl3 staining provided optimum effects for H2O2 localization in E. coli. The modified process of TEM provides very efficient protection for H2O2 localization and more accurate quantization for the H2O2 accumulation in bacterial cells. Microsc. Res. Tech., 2013. © 2012 Wiley Periodicals, Inc.
Baseline factors and early viral response (week 4) to antiviral therapy with peginterferon and ribavirin for predicting sustained virologic response in patients infected with hepatitis C virus genotype 1: A multicenter study
Authors: Toyoda Hidenori , Kumada Takashi , Shimada Noritomo , Takaguchi Koichi , Ide Tatsuya , Sata Michio , Ginba Hiroyuki , Matsuyama Kazuhiro , Izumi Namiki 
Published: November 2012

AbstractBoth baseline predictive factors and viral response at week 4 of therapy are reported to have high predictive ability for sustained virologic response to peginterferon and ribavirin combination therapy in patients with hepatitis C virus (HCV) genotype 1. However, it is not clear how these baseline variables and week 4 response should be combined to predict sustained virologic response. In this multicenter study, the authors investigated the impact of baseline predictive factors on the predictive value of week 4 viral response. Receiver‐operating characteristic curve analyses were performed to evaluate the ability of week 4 reduction in HCV RNA levels to predict sustained virologic response in 293 Japanese patients infected with HCV genotype 1b. Analyses were performed in all patients and in patient subgroups stratified according to baseline variables. Overall, week 4 viral reduction demonstrates a high predictive ability for sustained virologic response. The sensitivity, specificity, positive predictive value (PPV), negative predictive value, and accuracy were higher than those of viral reduction at week 12. However, the best cut‐off levels differ depending on the baseline factors and they were lower in patients with unfavorable baseline predictors. When patients had the TG/GG rs8099917 genotype, the best cut‐off was markedly low with low PPV. Week 4 viral response can be a predictor of sustained virologic response in patients with HCV genotype 1 and is better than week 12 viral response. However, the cut‐off levels should be modified based on the baseline predictive variables. J. Med. Virol. 85:65–70, 2012. © 2012 Wiley Periodicals, Inc.
Severe acute hepatitis B in a treatment‐naïve patient with antiviral drug resistant mutations in the polymerase gene
Authors: Morando Filippo , Rosi Silvia , Fasolato Silvano , Cavallin Marta , Gola Elisabetta , Gatta Angelo , Angeli Paolo 
Published: November 2012

AbstractThis is a case of 62 years old Caucasian treatment‐naïve patient who developed a severe acute hepatitis B infection soon after a trip to Thailand. The infection was due to genotype C HBV which was found to be resistant to lamivudine and telbivudine. The patient was treated with tenofovir resulting in complete suppression of viral replication and complete clinical and laboratory remission of acute hepatitis. Later the patient also developed seroconversion of HBeAg to anti‐HBe and of HBsAg to anti‐HBs. This case demonstrates that mutations of HBV polymerase associated with lamivudine, telbivudine, and adefovir resistance can be present also in untreated patients with severe acute hepatitis B. This suggests that in the clinical context, which represents a life threatening condition, a baseline resistance‐testing should be an additional marker in the diagnostic evaluation process. Finally, this case report seems to support the use of tenofovir for the immediate treatment of severe acute hepatitis B. J. Med. Virol. 85:210–213, 2013. © 2012 Wiley Periodicals, Inc.
HIV‐1 drug resistance‐associated mutations among antiretroviral‐naive thai patients with chronic HIV‐1 infection
Authors: Manosuthi Weerawat , Thongyen Supeda , Nilkamhang Samruay , Manosuthi Sukanya , Sungkanuparph Somnuek 
Published: November 2012

AbstractAntiretroviral therapy (ART) has increased in resource‐limited settings. This study determined the prevalence of HIV‐1 drug resistance‐associated mutations (DRAMs) among patients with chronic HIV‐1 infections and compare DRAMs between CRF01_AE and B subtypes. ART‐naive Thai patients who had ART initiation between 2010 and 2011 were enrolled prospectively. Genotypic assays were performed on viral reverse transcriptase and protease genes within 4 weeks before starting ART. DRAMs were assessed using the International AIDS Society‐USA 2011 list. A total of 330 patients were included. HIV‐1 subtypes included CRF01_AE (73%), B (23.9%), and others (3.1%). Median (IQR) CD4+ was 66 (23–172) cells/mm3 and median (IQR) HIV‐1 RNA was 5.2 (4.6–5.8) log copies/ml. The prevalence of patients with ≥1 DRAMs for any antiretroviral agents was 17.6%. DRAM prevalence was 17% for non‐nucleoside reverse transcriptase inhibitors (NNRTIs), 0.6% for NRTIs, and 0.6% for protease inhibitors (PIs). DRAMs to NNRTIs were V106I (7%), V179D (4.2%), V179T (1.8%), E138A (1.5%), V90I (1.2%), K103N (0.9%), Y181C (0.9%), and P225H (0.3%). DRAMs to NRTIs were M184V (0.3%) and T215S (0.3%). The only major DRAM for PIs was M46L (0.6%). Minor DRAMs to PIs including I13V, M36I, H69K, and L89M were observed more frequently in CRF_01 AE. By multivariate analysis, the factors “HIV‐1 subtype B” and “low pretreated CD4+ cell count” were associated with a higher rate of DRAMs. HIV‐1 DRAMs, especially to NNRTIs, are emerging in a middle‐income country after widespread use of NNRTI‐based ART. HIV genotypic assays before ART initiation in patients with chronic HIV‐1 infection should be considered. J. Med. Virol. 85:194–199, 2013. © 2012 Wiley Periodicals, Inc.
Infection with high‐risk HPV types among female sex workers in northern Vietnam
Authors: Hoang Huyen Thi Thanh , Ishizaki Azumi , Nguyen Cuong Hung , Tran Vuong Thi , Matsushita Kaori , Saikawa Kunikazu , Hosaka Norimitsu , Pham Hung Viet , Bi Xiuqiong , Ta Van Thanh , Van Pham Thuc , Ichimura Hiroshi 
Published: November 2012

AbstractVaccines against two high‐risk human papillomavirus (HPV) types, HPV‐16, and HPV‐18, are in use currently, with high efficacy for preventing infections with these HPV types and consequent cervical cancers. However, circulating HPV types can vary with geography and ethnicity. The aim of this study was to investigate the prevalence of HPV types and the association between HPV types and abnormal cervical cytology among female sex workers in Northern Vietnam. Cervical swabs and plasma samples were collected from 281 female sex workers at two health centers in Hanoi and Hai Phong in 2009. The HPV L1 gene was amplified by PCR using original and modified GP5+/6+ primers. Amplified PCR products were genotyped by the microarray system GeneSquare (KURABO) and/or clonal sequencing. Of the 281 women, 139 (49.5%) were positive for HPV DNA. Among the HPV‐positive samples, 339 strains and 29 different types were identified. Multiple‐type and high risk‐type HPV infections were found in 85 (61.2%) and 124 (89.2%) women, respectively. The most common genotype was HPV‐52, followed by HPV‐16, HPV‐18, and HPV‐58. Abnormal cervical cytology was detected in 3.2% (9/281) of the women, and all of these samples were positive for HPV‐DNA. Age ≤25 years and infection with human immunodeficiency virus were associated positively with HPV infection among the women while ever smoking was associated negatively. These results show that HPV‐52 is most prevalent among female sex workers in Northern Vietnam, most of whom had normal cervical cytology. This information may be important for designing vaccination strategies in Vietnam. J. Med. Virol. 85:288–294, 2013. © 2012 Wiley Periodicals, Inc.
Genetic and antigenic evolution profiles of G1 rotaviruses in córdoba, Argentina, during a 27‐year period (1980–2006)
Authors: Barril Patricia , Martínez Laura , Giordano Miguel , Masachessi Gisela , Isa María , Pavan Jorge , Glikmann Graciela , Nates Silvia 
Published: November 2012

AbstractRotavirus G1 strains represent the most common genotype that causes diarrhea in humans and has been incorporated into both, monovalent and multivalent, rotavirus licensed vaccines. The aim of this study was to determine the evolution profile of G1 rotaviruses in Córdoba, Argentina, over a 27‐year period (1980–2006). Intragenotype diversity, represented by lineages within rotavirus circulating strains, was observed. Phylogenetic analysis of the VP7‐gene of G1 rotavirus clinical strains showed the circulation of G1 lineage IV and V strains in the 1980s, and co‐circulation of lineage I and II strains in the 1990s and 2000–2006. The distribution of G1 in lineages could be linked to multiple nucleotide substitutions distributed across lineages that did not correlate with the emergence of G1 antigenic variants. Moreover, temporal lineage distribution was not linked to significant changes in G1 prevalence. Therefore, the continuous and dominant circulation of G1 over time could not be related to the emergence of antigenic variants in the community. Continuous rotavirus surveillance is necessary to understand rotavirus evolution and to measure how genetic and antigenic changes might affect the effectiveness of vaccines in the future. J. Med. Virol. 85:363–369, 2013. © 2012 Wiley Periodicals, Inc.
A diatom‐based reconstruction of summer sea‐surface salinity in the Southern Okinawa Trough, East China Sea, over the last millennium
Authors: Li Dongling , Knudsen Mads Faurschou , Jiang Hui , Olsen Jesper , Zhao Meixun , Li Tiegang , Knudsen Karen Luise , Seidenkrantz Marit‐Solveig , Sha Longbin 
Published: November 2012

AbstractA high‐resolution diatom record from site MD05‐2908 in the Southern Okinawa Trough, East China Sea, reveals pronounced multidecadal‐ to centennial‐scale palaeoceanographic changes throughout the last millennium. Summer sea‐surface salinity (SSS) was reconstructed using a weighted averaging partial least squares diatom‐based training set. The reconstructed SSS shows slightly decreasing values during the period AD 905–1930 with considerable fluctuations superimposed on this general trend. Relatively high‐salinity conditions during the interval AD 905–1450 probably suggest a low flood frequency in north‐eastern Taiwan. Furthermore, the high SSS values are associated with a strong and stable influence of the Kuroshio Current on the Southern Okinawa Trough during the Medieval Climate Anomaly. The period AD 1450–1930 is characterized by three low‐salinity intervals (AD 1450–1500, AD 1625–1725 and AD 1770–1880) separated by periods of relatively high salinity. The low SSS intervals indicate increased freshwater discharge into the Southern Okinawa Trough during the Little Ice Age, probably as a result of higher flood frequencies in north‐eastern Taiwan. Spectral and wavelet analyses suggest that this pattern was linked to multidecadal variations in summer SSS, presumably associated with the Pacific Decadal Oscillation. Copyright © 2012 John Wiley & Sons, Ltd.
Wild salmon authenticity can be predicted by 1H‐NMR spectroscopy
Authors: Capuano Edoardo , Lommen Arjen , Heenan Samuel , de la Dura Angela , Rozijn Maikel , van Ruth Saskia 
Published: November 2012

AbstractThe combination of 1H NMR fingerprinting of muscle lipids from fresh and processed (frozen, canned and smoked) Atlantic salmon (Salmo salar) with supervised multivariate analysis was applied to differentiate wild and farmed fish. Soft Independent Modelling of Class Analogy (SIMCA) allowed classification of samples according to the wild and farmed status with a 100% correct classification. The discrimination is mainly based on the higher content in oleic and linoleic acid in farmed fish.
Syntheses, characterization and future outlook of structured phospholipids
Authors: Cheong Ling‐Zhi , Guo Zheng , Xu Xuebing 
Published: November 2012

AbstractCrude oils contain phospholipids which are removed during the degumming stage of refining. This valuable product has been used as an emulsifier in food, feed and cosmetics. Most of the naturally occurring phospholipids contain unsaturated fatty acids which are prone to oxidation. Thus, it is worth modifying the structure of phospholipids to improve their physical, chemical and functional properties. This paper considers the possibilities of modifying the phospholipids structure and the properties of the modified compounds.
Synthesis and microstructural study of stereoblock elastomeric polypropylenes from metallocene catalyst (2‐PhInd)2ZrCl2 activated with cocatalyst mixtures
Authors: Nejabat Gholam‐Reza , Nekoomanesh Mehdi , Arabi Hassan , Salehi‐Mobarakeh Hamid , Zohuri Gholam‐Hossein , Omidvar Mojtaba , Miller Stephen A. 
Published: November 2012

AbstractVarious elastomeric polypropylenes (PPs) are synthesized through homogeneous propylene polymerization with metallocene catalyst (2‐PhInd)2ZrCl2 in the presence of different cocatalyst mixtures: triethylaluminum (TEA)/methylaluminoxane (MAO) or triisobutylaluminum (TIBA)/MAO in the range of AlAlR3/AlMAO = 0.0–0.9. The cocatalyst formulation impacts the resultant polymer microstructure and the thermal and dynamic mechanical properties of the produced PPs. 13C NMR analysis of the polymers reveals essentially atactic PP, with mmmm = 7.9%, when AlAlR3/AlMAO = 0.0. The mmmm pentad content is maximized when AlAlR3/AlMAO = 0.8; for TIBA, mmmm = 23.5%; and for TEA, mmmm = 17.6%. Differential scanning calorimetry analysis and dynamic mechanical thermal analysis corroborate these findings. Specifically, Tm, ΔHm, and Tg are essentially maximized under these conditions, and the minimum damping is observed for AlAlR3/AlMAO = 0.6–0.8. 1H NMR analysis of the mixtures of catalyst and cocatalysts (without monomer) shows very minor differences for [Zr]:AlAlR3 in the range of 1:1–1:5. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013