93,891 research outputs found
B-H. Han. Hiperculturalidad. Barcelona: Editorial Herder, 2018.
No full textB-H. Han. Hiperculturalidad. Barcelona: Editorial Herder, 2018. USB-H. Han. Hiperculturalidad. Barcelona: Editorial Herder, 2018. E
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Search for direct CP violation in D0→h−h+ modes using semileptonic B decays
No full textA search for direct CP violation in D0 → h-h+ (where h = K or π) is presented using data corresponding to an integrated luminosity of 1.0 fb-1 collected in 2011 by LHCb in pp collisions at a centre-of-mass energy of 7 TeV. The analysis uses D0 mesons produced in inclusive semileptonic b-hadron decays to the D0μX final state, where the charge of the accompanying muon is used to tag the flavour of the D0 meson. The difference in the CP-violating asymmetries between the two decay channels is measured to be ΔACP = ACP(K-K+) - ACP(π-π+) = (0.49± 0.30 (stat) ± 0.14 (syst))%
Miscellaneous correspondence from the H. B. Clawson papers, 1872-1895
No full textMiscellaneous Correspondence from the H. B. Clawson papers, 1872-1895: (1) Letter dated 24 December 1872 at Salt Lake City, Utah, by Robert Williams to Hiram B. Clawson, thanking him for gifts (1 page); (2) Letter dated 6 May 1878 at Liverpool, England, by Charles Nibley to Bradley Clawson (1 page); (3) Letter dated 21 December 1886? at Chicago, Illinois, by B. R. Wells of M.D. Wells & Company to Hiram B. Clawson, regretting missing him when he was in town (1 page); (4) Letter dated 2 March 1881 at Middlefield [State unknown] by Matthew Smith to "Mrs. Clawson" (Ellen S. Clawson, Hiram\u27s first wife) (2 pages); (5) Letter dated 29 January 1884 at South Bend, Indiana, by Mrs. G. Foote (probably mother of James Foote, who married Ellen\u27s daughter Georgia) to Mrs. [Ellen S.] Clawson, prior to the expected visit of Ivie Clawson (2 pages); (6) Letter dated 21 April 1881 at New York City by Titus B. Eldridge to H. B. Clawson, upon receiving a gift of the Book of Mormon (2 pages); (7) Letter dated 18 August 1891 at Hayden, Idaho, by "Ed" to Ivie Clawson at Soda Springs, Idaho, describing his travels from Salt Lake City through Idaho; (8) Letter dated 26 April 1892 at East Mill Creek by Nellie Fisher to Ellen Clawson, with questions about the history of "Primary" (2 pages); (9) Letter dated 29 March 1894 at San Francisco, California, by Florence [no surname given], to her cousin Ivie Clawson at Salt Lake City, Utah (4 pages); (10) Letter dated 23 August 1894 at Paris, Idaho, by Lilian Spencer to her cousin Ivie Clawson at Salt Lake City (3 pages); (11) Letter dated 1 January 1895 at Boston, Massachusetts, by Jean C. Thatcher to Ivie Clawson Greene, congratulating her on her marriage (pages); (12) Letter dated 13 April 1895 by Henry F. CLark, Manager of the Literary Bureau, Curtis Publishing Company, at Philadelphia, Pennsylvania, to E. C. Clawson, providing information on author Edward Bellamy; (13) Letter dated 6 April [no year] by John T. White to Ivie and Winnie Clawson; (14) Letter [undated] by Mary DeVol (?) at Council Bluffs to Mrs. [Ellen S.] Clawso
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
A common HLA-DPA1 variant is associated with hepatitis B virus infection but fails to distinguish active from inactive Caucasian carriers
No full textBackground and Aims: Chronic infection with the hepatitis B virus (HBV) is a major health issue worldwide. Recently, single nucleotide polymorphisms (SNPs) within the human leukocyte antigen (HLA)-DP locus were identified to be associated with HBV infection in Asian populations. Most significant associations were observed for the A alleles of HLA-DPA1 rs3077 and HLA-DPB1 rs9277535, which conferred a decreased risk for HBV infection. We assessed the implications of these variants for HBV infection in Caucasians.
Methods: Two HLA-DP gene variants (rs3077 and rs9277535) were analyzed for associations with persistent HBV infection and with different clinical outcomes, i.e., inactive HBsAg carrier status versus progressive chronic HBV (CHB) infection in Caucasian patients (n = 201) and HBsAg negative controls (n = 235).
Results: The HLA-DPA1 rs3077 C allele was significantly associated with HBV infection (odds ratio, OR = 5.1, 95% confidence interval, CI: 1.9–13.7; p = 0.00093). However, no significant association was seen for rs3077 with progressive CHB infection versus inactive HBsAg carrier status (OR = 2.7, 95% CI: 0.6–11.1; p = 0.31). In contrast, HLA-DPB1 rs9277535 was not associated with HBV infection in Caucasians (OR = 0.8, 95% CI: 0.4–1.9; p = 1).
Conclusions: A highly significant association of HLA-DPA1 rs3077 with HBV infection was observed in Caucasians. However, as a differentiation between different clinical courses of HBV infection was not possible, knowledge of the HLA-DPA1 genotype cannot be translated into personalized anti-HBV therapy approaches
Boron-mediated directed aromatic C–H hydroxylation
No full textTransition metal-catalysed C–H hydroxylation is one of the most notable advances in synthetic chemistry during the past few decades and it has been widely employed in the preparation of alcohols and phenols. The site-selective hydroxylation of aromatic C–H bonds under mild conditions, especially in the context of substituted (hetero)arenes with diverse functional groups, remains a challenge. Here, we report a general and mild chelation-assisted C–H hydroxylation of (hetero)arenes mediated by boron species without the use of any transition metals. Diverse (hetero)arenes bearing amide directing groups can be utilized for ortho C–H hydroxylation under mild reaction conditions and with broad functional group compatibility. Additionally, this transition metal-free strategy can be extended to synthesize C7 and C4-hydroxylated indoles. By utilizing the present method, the formal synthesis of several phenol intermediates to bioactive molecules is demonstrated
Signaling role of intracellular iron in NF-kappa B activation
No full textIron chelators inhibit endotoxin-induced NF-B activation in hepatic macrophages (HMs), suggesting a role for the intracellular chelatable pool of iron in NF-B activation. The present study tested this hypothesis. Analysis of Fe59-loaded HMs stimulated with lipopolysaccharide (LPS), revealed a previously unreported, transient rise in intracellular low molecular weight (LMW)·Fe59 complex ([LMW·Fe]i) at 2 min returning to the basal level within 15 min. The [LMW·Fe]i response preceded IB kinase (IKK) (15 min) and NF-B (30 min) activation. Iron chelators (1,2-dimethyl-3-hydroxypyridin-4-one and N,N'-bis-2-hydroxybenzylethylenediamine-N,N'-diacetic acid) abrogated the [LMW·Fe]i response and IKK and NF-B activation. The [LMW·Fe]i response was also observed in tumor necrosis factor (TNF)-stimulated HMs and RAW264.7 cells treated with LPS and interferon- but not in primary rat hepatocytes or myofibroblastic cells exposed to LPS or TNF. Both [LMW·Fe]i response and IKK activation in LPS-stimulated HMs were inhibited by diphenylene iodonium (nonspecific inhibitor for flavin-containing oxidases), L-N6-(1-iminoethyl)lysine (selective iNOS inhibitor), and adenoviral-mediated expression of a dominant negative mutant of Rac1 or Cu,Zn-superoxide dismutase, suggesting the role of ·NO and O in mediating the iron signaling. In fact, this inhibition was recapitulated by a cell-permeable scavenger of ONOO, 5,10,15,20-tetrakis (4-sulfonatophenyl)porphyrinato iron (III) chloride. Conversely, ONOO alone induced both [LMW·Fe]i response and IKK activation. Finally, direct addition of ferrous iron to cultured HMs activated IKK and NF-B. These results support a novel signaling role for [LMW·Fe]i in IKK activation, which appears to be induced by ONOO and selectively operative in macrophages. <br/
Boron pretreatment promotes phosphorization of FeNi catalysts for oxygen evolution
No full textOxygen evolution reaction (OER) is a crucial half-reaction for many energy conversion technologies, which requires efficient catalysts to boost its sluggish kinetics. Herein, the FeNi catalyst with a high phosphating level (HP-FexNi2−xP) is constructed by a three-step synthetic route: (i) hydrothermal deposition of lamellar sheets, (ii) NaBH4 pretreatment, and (iii) in situ phosphorization. FeNi layered double lamellar hydroxides were synthesized as the pre-catalysts. Then NaBH4 pretreatment was used to remove the oxide impurities and introduce oxygen vacancies to promote phosphorization in the subsequent process. Finally, HP-FexNi2−xP nanosheets were achieved, with several advantages like abundant exposed active sites, high conductivity, and accessible mass transport channels. During the OER process, FeNiOOH/HP-FexNi2−xP interfaces are formed through spontaneous electrochemical activation and surface reconstruction. Benefitting from the synergistic interfacial effect and abundant exposed active sites, the NiFe based catalysts show an overpotential of ≈ 208 mV to reach 10 mA cm−2 in 1 M KOH, and a stability of 200 h at 1 A cm−2. Overall, this work reports the rational design and preparation of a highly active OER catalyst, but also provides a general route through NaBH4 pretreatment, which can be usefully applied to promote phosphorization in other systems of interest for catalytic applications
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