Is there a correlation between journal impact factor and researchers’ performance? A study comprising the fields of clinical nephrology and neurosciences

Quantifying the scientific performance of investigators has become an integral part of decision-making in research policy. The aim of the present study was to evaluate if there is a correlation between journal impact factor (IF) and researchers’ influence among a selected group of Brazilian investigators in the fields of clinical nephrology and neurosciences. This study was based on 94 senior investigators (36 in clinical nephrology and 58 in clinical neurosciences) receiving productivity scholarships from the Brazilian Council for Scientific and Technological Development (CNPq) according to a list provided by the agency in February 2009. Scientific performance indicators included in the analysis were: number of papers indexed by the Web of Science and Scopus databases, number of citations, h- and m-index. IFs were analyzed as (1) cumulative IF (∑IF), (2) IF adjusted by time (IF/t), and (3) average IF. There was a moderate positive correlation only between ∑IF and two indicators: total number of citations (P < 0.001) and h-index (P < 0.001). There was also a positive correlation between IF/t and m-index (P < 0.001). There was an agreement in these correlations between both groups (clinical nephrology and neurosciences). No significant correlation between the average IF and any of the scientific indicators was detected. A cut-off of 10.53 for IF/t showed the best performance in predicting researchers with m-index equal to or greater than 1. According to our findings, other qualitative and quantitative instruments rather than IF are clearly needed for identifying researchers with outstanding scientific output.     

Response surface modeling to predict fluid loss from beef strip loins and steaks injected with salt and phosphate with or without a dehydrated beef protein water binding adjunct

This study was conducted using response surface methodology to predict fluid loss from injected beef strip steaks as influenced by levels of salt and sodium phosphates (SP) in the injection brine. Also, a beef-based dehydrated beef protein (DBP) water binding ingredient was evaluated. Paired U.S. select beef strip loins were quartered before being injected with 110% of initial weight with brines containing various concentrations of salt and SP (CON) or salt, SP and 5% DBP. Steaks were sliced, overwrapped and stored in the dark for 4 d. Purge values ranged from 0.6% to 4.6% for CON and 0.3% to 2.1% for DBP. Fluid losses when accounting for the fluid lost from injection to slicing were as high as 6.8% for CON brines, but only 2.8% for DBP brines. The equations generated here and the DBP product could help producers achieve acceptable purge while reducing sodium use.     

Controlled hydrothermal growth and optical characterization of wide band gap Be x Zn1−x O nanorod arrays

Wide band gap Be _x Zn_1?x O nanorod arrays on Zn foil substrates have been successfully prepared for the first time by a facile hydrothermal method at 80 °C for 24 h. The structure, morphology, and optical properties of the nanorod arrays were studied by X-ray diffraction (XRD), field emission scanning electron microscopy, and photoluminescence (PL). The composition x and band gap energy of the Be _x Zn_1?x O nanorod arrays were calculated from XRD and PL results, respectively. The results show that the PL emission peak energy increased with increasing x, as expected, and these materials should be suitable for developing UV-based optoelectronics.     

Digitized RF-over-fiber as a cost-effective and energy-efficient backhaul option for wireless communications

Digitized RF-over-fiber technique based on bandpass sampling theory is studied as an alternative of analog radio-over-fiber to deliver wireless signals, taking advantage of digital optical link and realizing simpler base station architecture. In this paper, we present an overview of our recent research on digitized radio-over-fiber (RoF) technique, including discussions on the designing issues and possible solutions, proof-of-concept demonstrations and experimental results. Then, we examine the energy efficiency of the digitized RoF technique using a generic base station (BS) power model and compare with conventional BS designs. Based on the estimated energy consumption per square meter, digitized RoF technique has advantage for larger cell size.     

A simulator study of the effects of singing on driving performance

This study aimed to investigate how singing while driving affects driver performance. Twenty-one participants completed three trials of a simulated drive concurrently while performing a peripheral detection task (PDT); each trial was conducted either without music, with participants listening to music, or with participants singing along to music. It was hypothesised that driving performance and PDT response times would be impaired, and that driver subjective workload ratings would be higher, when participants were singing to music compared to when there was no music or when participants were listening to music. As expected, singing while driving was rated as more mentally demanding, and resulted in slower and more variable speeds, than driving without music. Listening to music was associated with the slowest speeds overall, and fewer lane excursions than the no music condition. Interestingly, both music conditions were associated with slower speed-adjusted PDT response times and significantly less deviation within the lane than was driving without music. Collectively, results suggest that singing while driving alters driving performance and impairs hazard perception while at the same time increasing subjective mental workload. However, singing while driving does not appear to affect driving performance more than simply listening to music. Further, drivers’ efforts to compensate for the increased mental workload associated with singing and listening to music by slowing down appear to be insufficient, as evidenced by relative increases in PDT response times in these two conditions compared to baseline.     

Trichloramine in swimming pools--formation and mass transfer

Trichloramine is a volatile, irritant compound of penetrating odor, which is found as a disinfection by-product in the air of chlorinated indoor swimming pools from reactions of nitrogenous compounds with chlorine. Acid amides, especially urea, ammonium ions and α-amino acids have been found as most efficient trichloramine precursors at acidic and neutral pH. For urea a relative NCl₃ formation of 96% at pH 2.5 and 76% at pH 7.1 was determined. Even under sub-stoichiometric molar ratios of Cl/N the formation of NCl₃ is favored over mono and dichlorinated products. However, the reaction kinetics of urea with chlorine is slow under conditions relevant for swimming pools. Also the mass transfer of NCl₃ from water to the gas phase which was calculated by the Deacon’s boundary layer model could be shown as a relatively slow process. Mass transfer would take 20 h or 5.8 d for a rough or a quiescent surface of the water, respectively. This is much more than a typical turnover rate of 6-8 h of a treatment cycle of a 25 m swimming pool. Therefore processes to remove NCl₃ and its precursors can help to minimize the exposure of bathers.     

A colorimetric response to hydrogen sulfide

Two simple Cu(II) chromophores [Cu(acac)(dmp)](NO₃) (1) and [Cu(acac)(dpph)](NO₃) (2) (acac = acetylacetone, dmp = 2,9-dimethyl-1,10-phenanthroline and dpph = 4,7-diphenyl-1,10-phenanthroline) have been synthesised and immobilized into a highly permeable polymer matrix and subsequently used in the optical detection of low levels of hydrogen sulfide (10 ppm) over a 2 min period. The system is responsive to a concentration one-tenth that quoted as being immediately dangerous to life and health (IDLH) value (100 ppm) by the National Institute for Occupational Safety and Health (NIOSH). The UV–vis spectral change is a consequence of the hydrogen sulfide gas reducing the Cu(II) to Cu(I) in the polymer matrix. A crystal structure of [Cu(acac)(dpph)](NO₃) (2) was obtained and will also be discussed.     

Age Differences in Adults’ Use of Referring Expressions

The aim of this article is to investigate whether choosing the appropriate referring expression requires taking into account the hearer’s perspective, as is predicted under some versions of bidirectional Optimality Theory but is unexpected under other versions. We did this by comparing the results of 25 young and 25 elderly adults on an elicitation task based on eight different picture stories, and a comprehension task based on eight similar written stories. With respect to the elicitation task, we found that elderly adults produce pronouns significantly more often than young adults when referring to the old topic in the presence of a new topic. With respect to the comprehension task, no significant differences were found between elderly and young adults. These results support the hypothesis that speakers optimize bidirectionally and take into account hearers when selecting a referring expression. If the use of a pronoun will lead to an unintended interpretation by the hearer, the speaker will use an unambiguous definite noun phrase instead. Because elderly adults are more limited in their processing capacities, as is indicated by their smaller working memory capacity, as speakers they will not always be able to reason about the hearer’s choices. As a result, they frequently produce non-recoverable pronouns.     

Unraveling the differential effects of motivational and skills, social, and self-management measures from traditional predictors of college outcomes.

The authors report on a large-scale study examining the effects of self-reported psychosocial factors on 1st-year college outcomes. Using a sample of 14,464 students from 48 institutions, the authors constructed hierarchical regression models to measure the predictive validity of the Student Readiness Inventory, a measure of psychosocial factors. Controlling for institutional effects and traditional predictors, the authors tested the effects of motivational and skill, social, and self-management measures on academic performance and retention. Academic Discipline was incrementally predictive of academic performance (grade-point average) and retention. Social Activity and Emotional Control also helped predict academic performance and retention, whereas Commitment to College and Social Connection offered incremental prediction of retention. This study elaborates recent meta-analytic findings (S. Robbins et al., 2004), demonstrating the salience of a subset of motivational, social, and self-management factors. Future research questions include how measures of psychosocial factors can be used to aid students, the salience of these measures over the entire college experience and for predicting job performance, and the need for testing theoretical models for explaining postsecondary educational outcomes incorporating traditional, motivational, self-management, and social engagement factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parallel recovery in a bilingual aphasic: A neurolinguistic and fMRI study.

In bilingual aphasics, the neural correlates of rehabilitation benefits and their generalization across languages are still scarcely understood. The authors present the case of a highly proficient bilingual woman (Flemish, L1/Italian, L2) with chronic aphasia who, in the presence of the same pattern of impairment in both languages, showed parallel recovery in both languages after long-term rehabilitation therapy in L2. The authors postulated that this recovery was due to the engagement of the same neural substrates. To confirm this the authors used an event-related functional magnetic resonance imaging (fMRI) paradigm to explore cortical activation during an overt picture naming task, performed in both Flemish and Italian once before and once after 2 weeks of training in L2. Behaviorally, the patient showed complete recovery of both languages. The fMRI results indicated that the same cerebral regions were recruited for both languages before and after training. Increasing activations were observed perilesionally and in homologous contralesional areas. Our data, in agreement with previous results of fMRI studies in healthy bilinguals, indicate a promising direction for future research on the neural mechanisms associated with recovery in bilingual aphasics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)