4,080 research outputs found
Assessing the accuracy of the h and g indexes for measuring researchers’ productivity
No full textBibliometric indicators are increasingly used in support of decisions about recruitment, career advancement, rewards, and selective funding for scientists. Given the importance of the applications, bibliometricians are obligated to carry out empirical testing of the robustness of the indicators, in simulations of real contexts. In this work, we compare the results of national-scale research assessments at the individual level, based on the following three different indexes: the h-index, the g-index, and “fractional scientific strength” (FSS), an indicator previously proposed by the authors. For each index, we construct and compare rankings lists of all Italian academic researchers working in the hard sciences during the period 2001–2005. The analysis quantifies the shifts in ranks that occur when researchers' productivity rankings by simple indicators such as the h- or g-indexes are compared with those by more accurate FSS
A robust benchmark for the h- and g-indexes
No full textThe use Hirsch’s h-index as a joint proxy of the impact and productivity of a scientist’s research work continues to gain ground, accompanied by the efforts of bibliometrists to resolve some of its critical issues, through the application of a number of more or less sophisticated variants. However, the literature does not reveal any appreciable attempt to overcome the objective problems of measuring h-indexes on a large scale, for purposes of comparative evaluation. Scientists may succeed in calculating their own h-indexes but, being unable to compare them to those of their peers, they are unable to obtain truly useful indications of their individual research performance. This study proposes to overcome this gap, measuring the h- and Egghe’s g-indexes of all Italian university researchers in the hard sciences, over a 5-year window. Descriptive statistics are provided concerning all of the 165 subject fields examined, offering robust benchmarks for those who wish to compare their individual performance to those of their colleagues in the same subject field
Artur, G., Berg, R., Gilloteaux, G. et autres Tahiti et ses îles
No full textViel Philippe. Artur, G., Berg, R., Gilloteaux, G. et autres Tahiti et ses îles. In: Journal de la Société des océanistes, n°28, tome 26, 1970. p. 264
Ringraziamento a FREGO MAURO in: IACOBONE M., BARZON L., PORZIONATO A., MASI G., MACCHI V., MARINO F, VIEL G., FAVIA G. Parafibromin expression, single-gland involvement, and limited parathyroidectomy in familial isolated hyperparathyroidism.
No full textConstraints on the primordial power spectrum from high-resolution Lyman α forest spectra and WMAP
No full textThe combined analysis of the cosmic microwave background on large scales and Lyman alpha forest on small scales provides a sufficiently long lever arm to obtain strong constraints on the slope and curvature of the power spectrum of primordial density fluctuations. We present results from the combination of the first year WMAP data and the dark matter power spectrum inferred by Viel, Haehnelt & Springel for two different sets of high-resolution and high signal-to-noise ratio quasar absorption spectra: the Croft et al. sample with a median redshift z = 2.72 and the LUQAS sample with a median redshift z = 2.125. The best-fitting value for the rms fluctuation amplitude of matter fluctuations is sigma(8) = 0.94 +/- 0.08 and n(s) = 0.99 +/- 0.03, if we do not include running of the spectral index. The best-fitting model with a running spectral index has parameters n(s) = 0.959 +/- 0.036 and n(run) = -0.033 +/- 0.025. The data are thus consistent with a scale-free primordial power spectrum with no running of the spectral index. We further include tensor modes and constrain the slow-roll parameters of inflation
The suitability of h and g indexes for measuring the productivity of research institutions
No full textThe Lyman α forest and WMAP year three
No full textA combined analysis of cosmic microwave background (CMB) and Lyman alpha forest data can constrain the matter power spectrum from small scales of about 1 h(-1) Mpc all the way to the horizon scale. The long lever arm and complementarity provided by such an analysis have previously led to a significant tightening of the constraints on the shape and the amplitude of the power spectrum of primordial density fluctuations. We present here a combined analysis of the WMAP three-year results with Lyman a forest data. The amplitude of the matter power spectrum sigma(8) and the spectral index n(s) inferred from the joint analysis of high-and low-resolution Lyman alpha forest data as analysed by Viel & Haehnelt are consistent with the new WMAP results to within 1 sigma. The joint analysis with the mainly low-resolution data as analysed by McDonald et al. suggests a value of sigma(8) that is similar to 2 sigma higher than that inferred from the WMAP three-year data alone. The joint analysis of the three-year WMAP and the Lyman alpha forest data also does not favour a running of the spectral index. The best-fitting values for a combined analysis of the three-year WMAP data, other CMB data, 2-degree Field (2dF) data and the Lyman alpha forest data are (sigma(8), n(s)) = (0.78 +/- 0.03, 0.96 +/- 0.01)
Purgatorio, canto IV
No full textIl contributo offre una innovativa lectura del IV canto del Purgatorio. Il canto è esaminato nella sua interezza ma viene data una interpretazione originale soprattutto del celebre personaggio di Belacqua, sottraendolo alle letture aneddodiche e riduttive tradizionali. Le ragioni di Belacqua sono invece pienamente valorizzate e consistono nel contrastare il pericoloso ardore conoscitivo e viatorio di Dante e della sua guida, secondo la spiritualità umile e paziente propria del regno purgatoriale. Da ciò il contrasto fra Belacqua e Dante viene letto in modo del tutto nuovo, ma assume un senso preciso nel momento in cui si comprende che l'anima ignora il privilegio del protagonista di visitare l'aldilà mentre è ancora in vita
An unusual case of suicide by sharp force
No full textA 43-year-old woman was found dead inside the bathtub in a sitting position with a knife embedded in chest. Multiple sharp force wounds were present: 4 stab wounds in the sternal region, 2 cut wounds in the neck, several longitudinal and transverse cuts in the arms. Scene circumstances and autopsy findings pointed toward a suicidal etiology. The case presented some particular aspects that allowed us to identify the mechanism of production of the lethal thoracic wound and to partially reconstruct the time-sequence of injuries
Is old stuff back? A fatal case of ethyl chloride sniffing
No full textBackground: Ethyl chloride (EC) or chloroethane is a colourless halogenated hydrocarbon gas regularly employed as a topical anaesthetic spray for pain-related injuries and muscle spasm in athletes. However, EC became also popular as a street drug in the 1980s. Brief inhalations of EC vapour can result in dizziness, euphoria, confusion, incoordination, hallucinosis, impairment of short-term memory and narcosis. Inhalation of higher doses, usually employed to “get high”, may be related to severe depression of the central nervous system. Indeed, toxicity and deaths have been reported so far. Case presentation: A 40-year-old man was found unresponsive after EC inhalation. EC determination was performed by dynamic headspace gas chromatography coupled to mass spectrometry. EC was detected in the peripheral blood (0.156 g/L), central blood concentration (0.203 g/L) and the lung and brain (19 and 25 mg/kg). EC in the vitreous humour showed a sensitively lower respect to blood (0.018 vs 0.203 g/L). Conclusions: Considering the results of toxicological analyses of investigations on the death scene besides the absence of any signs of trauma, death was attributed to inhalation of ethyl chloride
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