130,526 research outputs found
Finite-Larmor-radius equilibrium and currents of the Earth’s flank magnetopause
No full textWe consider the one-dimensional equilibrium problem of a shear-flow boundary layer within an ‘extended-fluid model’ of a plasma that includes the Hall and the electron pressure terms in Ohm’s law, as well as dynamic equations for anisotropic pressure for each species and first-order finite-Larmor-radius (FLR) corrections to the ion dynamics. We provide a generalized version of the analytic expressions for the equilibrium configuration given in Cerri et al., (Phys. Plasmas, vol. 20 (11), 2013, 112112), highlighting their intrinsic asymmetry due to the relative orientation of the magnetic field B, b = B/|B| , and the fluid vorticity w = curl(u) (‘ wb asymmetry’). Finally, we show that FLR effects can modify the Chapman–Ferraro current layer at the flank magnetopause in a way that is consistent with the observed structure reported by Haaland et al., (J. Geophys. Res. (Space Phys.), vol. 119, 2014, pp. 9019–9037). In particular, we are able to qualitatively reproduce the following key features: (i) the dusk–dawn asymmetry of the current layer, (ii) a double-peak feature in the current profiles and (iii) adjacent current sheets having thicknesses of several ion Larmor radii and with different current directions
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
Analgesia and sedation in high-risk critically ill patients: still waiting for evidence about remifentanil
No full text
BCL-6 gene mutations in primary cutaneous B-cell lymphomas
No full textWe analyzed mutations in the 5′ non-coding region of the BCL-6 gene in 46 cases of primary cutaneous B-cell lymphomas (PCBCL), using a polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) method. The results indicate that PCBCL display a low frequency of mutations and support a marginal zone B-cell origin for most of these neoplasms
Plasmacytoid dendritic cells : an overview of their presence and distribution in different inflammatory skin diseases, with special emphasis on Jessner’s lymphocytic infiltration of the skin and cutaneous lupus erythematosus
No full textBackground: Plasmacytoid dendritic cells (PDC) play a pivotal role in the induction of autoimmune diseases and other skin diseases. The present study focuses on the distribution patterns of PDC in patients with cutaneous lupus erythematosus (LE) and Jessner's lymphocytic infiltrate (LI) of the skin and compares them with other skin diseases. The goal was to scrutinize the involvement of PDC in LI, and to show that PDC present a specific pattern of distribution in various cutaneous disorders. Methods: 353 skin biopsies of LE (various subtypes), LI, and other inflammatory skin diseases as well as two halo melanocytic nevi and 10 epithelial tumors were immunohistochemically investigated for the presence of PDC by employing antibodies against CD123 and CD2AP. Results: PDC were constantly detected as distinct perivascular and periadnexal clusters in LE and LI. In other forms of dermatitis, PDC could be found as single cells or scattered throughout the infiltrate or beneath the epidermis. Conclusions: Our data suggest that the distribution of PDC in tumid LE and LI is identical, and this observation suggests that both designations signify one disease. The distinct PDC arrangement in LE represents as useful diagnostic tool in the differential diagnosis with other forms of dermatitis. Tomasini D, Mentzel T, Hantschke M, Cerri A, Paredes B, Rütten A, Schärer L, Kutzner H. Plasmacytoid dendritic cells: an overview of their presence and distribution in different inflammatory skin diseases, with special emphasis on Jessner's lymphocytic infiltrate of the skin and cutaneous lupus erythematosus. Copyrigh
A Neural Network Simulation of a Gas Turbine with a Waste Heat Recovery Section
No full textThe objective of the paper is to assess the feasibility of the neural network (NN) approach in power plant process evaluations. A "feed-forward'' technique with a back
propagation algorithm was applied to a gas turbine equipped with waste heat boiler and water heater. Data from physical ol empirical simulators of plant components were used
to train such a NN model. Results obtained using a conventional computing technique are compared with those of the direct method based on a NN approach. The NN simulator
was able to perform calculations in a really short computing time with a high degree of accuracy, predicting various steady-state operating conditions on the basis of inputs that
can be easily obtained,vith existing plant instrumentation. The optimization of NN parameters like number of hidden neurons, training sample size, and learning I ate is discussed
in the paper
Baltų kalbų skaitvardžių vartojimo dažnumas: kognityviniai, lingvistiniai ir kultūriniai faktoriai.
No full textStraipsnyje pristatomas tekstynų medžiaga paremtas lietuvių ir latvių kalbų skaitvardžių vartojimo dažnumo tyrimas. Surinkta medžiaga rodo šiuos požymius: a) didelis mažiausius skaičius įvardijančių skaitvardžių dažnumas; b) bendra dažnumo mažėjimo tendencija kiekvienos serijos (vienetų, dešimčių ir t. t.) elementų eilėje nuo pirmo iki paskutinio; c) dažnumo viršūnės dažnai atitinka svarbias struktūrines pozicijas sistemoje. Kartu su kitų kalbų duomenimis šie požymiai patvirtina, kad kalbos vartotojų universalūs kognityviniai gebėjimai ir jų ribotumas atlieka svarbų vaidmenį skaitvardžių dažnumo distribucijos struktūroje. Tuo pačiu metu kultūriniai faktoriai yra taip pat įtraukti į skaičių konceptų kognityvinės hierarchijos kūrimo procesą. Straipsnyje siūloma skirti įgimtą (kognityvinį) ir neįgimtą (lingvistinį ir kultūrinį) iškilumą. Pastarasis yra atsakingas už referencinių skaičių identifikaciją – taip suteikiama daugiau patikimumo iš dalies reliatyvistinei hipotezei, kad kalbos sistema daro įtaką kalbėtojų mentalinio žemėlapio formavimui skaičių kognityvinėje srityje. Reikšminiai žodžiai: Baltic; Lithuanian; Latvian; Corpus-based study; Numerals; Frequency; Cognitive saliencyThis work consists of a corpus-based study on the frequency of the use of numerals in Lithuanian and Latvian. The collected data display the following features: a) the high frequency of the lowest numerals; b) a generally decreasing trend from the first to the last element of each series (units, tens, etc.); c) peaks of frequency often corresponding to important structural positions in the system. In line with the data available for other languages, these features seem to confirm that the universal cognitive abilities and limitations of the speakers play a major role in structuring the frequency of the use of numerals. At the same time, cultural factors are also involved in the process of creating a cognitive hierarchy among number concepts. I suggest distinguishing between innate (cognitive) and non-innate (linguistic and cultural) saliency. The latter is responsible for the identification of reference numbers, thus giving greater credence to the partially relativistic hypothesis that the linguistic system influences the mental mapping of the speakers in the cognitive domain of numbers
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