45,189 research outputs found
Induction of EROD activity in European eel (Anguilla anguilla) experimentally exposed to B(a)P and βNP
No full textThe induction of liver ethoxyresorufin O-deethylase (EROD) activity was investigated in the European eel, Anguilla anguilla, collected from a Mediterranean brackish environment and experimentally exposed to benzo[a]pyrene (B[a]P) and h-naphthoflavone (BNF). Eels were injected intraperitoneally at increasing doses (0.1, 1, 10, and 50 mg/kg wet body weight) using corn oil as a carrier and sacrificed after 7 days. The main objectives of the present study are: (1) to assess of the sensitivity of EROD induction as a biomarker to polycyclic aromatic hydrocarbon (PAH) exposure; (2) to determine an EROD dose–response relationship of the contaminants used; and (3) to compare the efficiency of B[a]P and BNF as inducers of EROD activity. Results showed that both chemicals resulted in a dose-dependent EROD induction, but increases were not linear. EROD activity seemed to reach a plateau at the exposure of 10 mg/kg in both treatment groups; B[a]P was a more potent inducer than BNF was at the higher doses (10 and 50 mg/kg), while the opposite result was observed at the lower ones (0.1 and 1 mg/kg). The greatest induction occurred in eels treated with 10 mg/kg B[a]P, in which a 261-fold increase in EROD activity was observed. Results showed that EROD activity in A. anguilla is significantly induced by B[a]P and BNF exposure, responding to a wide range of concentrations of these contaminants. We infer that this tool may be suited as a diagnostic biomarker for biomonitoring PAHs pollution in Mediterranean brackish environments and further field research is suggeste
Presence of the endangered saproxylic species Cucujus haematodes (Coleoptera: Cucujidae) in Aspromonte National Park (Southern Italy)
No full textThe knowledge of the ecological preferences of threatened species is critical to all conservation programs. Analyses of habitats and ecological parameters of species are necessary to predict future distribution and responses to climate change. Cucujus haematodes Erichson, 1845 (Coleoptera: Cucujidae) is a threatened obligate saproxylic species, listed in the IUCN European Red List of Saproxylic Beetles. After a few decades of apparent absence, the species was recently found in Calabria (Southern Italy) in some good quality biotopes of the Sila National Park in association with Cucujus cinnaberinus (Scopoli, 1763) and Cucujus tulliae Bonacci, Mazzei, Horák & Brandmayr, 2012 (Coleoptera: Cucujidae). Field surveys carried out from 2014 to 2020 in Aspromonte National Park (Calabria) revealed large populations of C. haematodes. Larvae of C. haematodes were collected from under the bark of dead trees in 11 sampling areas within Aspromonte National Park. The presence of larvae of C. haematodes on the non-autochthonous conifer Pseudotsuga menziesii (Mirb.) Franco (Pinales: Pinaceae) was also reported for the first time in Italy
Letter from Arno B. Cammerer to J. R. Eakin
No full textLetter from Arno B. Cammerer to J. R. Eakin describing the procedure for purchasing Bright Angel Trail
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
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
Structure and growth of -bonacci words
No full textA binary word is called -decreasing, for , if every of its length
maximal factors of the form , , satisfies . We
bijectively link -decreasing words with certain prefixes of the cutting
sequence of the line . We show that the number of -decreasing words of
length grows as for some constant which depends on
but not on . We demonstrate that is the golden ratio,
is equal to the tribonacci constant, is -bonacci
constant. Furthermore, we prove that the function is strictly
increasing, discontinuous at every positive rational point, exhibits a fractal
structure related to the Stern--Brocot tree and Minkowski's question mark
function.Comment: 16 pages, 7 figures, 3 table
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Comparative induction of liver EROD and BaPMO activities in European eel (Anguilla anguilla) by benzo[a]pyrene and 2,3,7,8-tetrachlorodibenzo-p-dioxin: a laboratory study
No full textThe objective of the present study was to assess and compare the sensitivity of EROD and BaPMO enzymatic activities as biomarkers of exposure to increasing doses of benzo[a]pyrene (B[a]P) and polychlorinated 2,3,7,8-tetrachloro dibenzo-para-dioxin (2,3,7,8-TCDD) in Anguilla anguilla. Eels collected from a Mediterranean brackish environment were experimentally exposed to chemicals by intraperitoneal injection and sacrificed seven days later. Both EROD and BaPMO activities showed close dose-response relationships to chemicals, even, if the Presence of a plateau in EROD induction at concentrations above 10 mg/kg B[a]P is suggested. Higher induction occurred for EROD than for BaPMO activity in almost all the groups of exposure. Both EROD and BaPMO activities in A. anguilla appear to be suitable biomarkers to PAHs and PCDDs exposure and a higher sensitivity is suggested for EROD induction as biomarker of exposure to such chemicals
Induction of EROD activity in European eel (Anguilla anguilla) experimentally exposed to benzo(a)pyrene and b-naphtoflavone.
No full textBranching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
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