Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by ISI

  • isi web

  • Selected Abstracts

    The Illness/Injury Sensitivity Index: an examination of construct validity

    R. Nicholas Carleton M.A.
    Abstract The 11-item Illness/Injury Sensitivity Index [ISI; Taylor, 1993: J Behav Ther Exp Psychiatry 24:289,299] measures fears of injury and illness and has the potential to delineate some mechanisms underlying anxiety-associated chronic health conditions. In a principal components analysis in 2005, Carleton et al. [2005a: J Psychopathol Behav Assess 27:235,241] indicated that a two-factor solution (Fear of Injury and Fear of Illness) best explained the structure of the ISI. The primary purpose of this study was to examine the structural and construct validity of the ISI. Results supported a two-factor solution after removal of two overinclusive items. Although the measure demonstrated good factorial validity, convergent and discriminant validity require further evaluation. In addition, a substantial correlation with fear of pain suggests a shift in our perspective on what constitutes a fundamental fear. Future research implications are discussed. Depression and Anxiety 23:340,346, 2006. © 2006 Wiley-Liss, Inc. [source]

    The destinies of the low- and middle-income country submissions

    J. Konradsen
    Objective:, To measure the number of submissions to Acta Pyschiatrica Scandinavica from low- and middle-income countries (LIC/MIC) compared with submissions from high income countries (HIC), to compare the way through the peer review process for the three groups respectively, as well as how they do as published articles eventually. Method:, By help of the Acta Psychiatrica Scandinavica editorial office database all submissions of reviews of the literature, clinical overviews, original articles, brief communications, and case reports from 2002 through 2005 were analysed as to external/in-house review, acceptance/rejection, number of downloads from Blackwell-Synergy, and number of citations [Institute of Scientific Information (ISI)] in a comparison between HIC and LIC/MIC. Results:, About 14.6% of the total submissions in 2002/2003 came from LIC and MIC countries, 15.5% for the 2004/2005 period. In both periods, a larger portion of LIC/MIC manuscripts were reviewed exclusively in-house compared with HIC ones and among those papers reviewed by external experts a smaller proportion of the submissions from HIC countries were rejected than of those from LIC and MIC countries. From the first to the second period there is a significant increase of proportion of submitted LIC/MIC papers accepted for publication compared with HIC papers. Full text download and citation statistics did not differ significantly between HIC and LIC/MIC. Conclusion:, Low- and middle-income countries manuscripts do gradually better in the competition with HIC papers in Acta Psychiatrica Scandinavica. The major observation is that the total number of LIC/MIC submissions to the journal is still low. [source]

    Binge-like ethanol exposure during the early postnatal period impairs eyeblink conditioning at short and long CS,US intervals in rats

    Tuan D. Tran
    Abstract Binge-like ethanol exposure on postnatal days (PD) 4,9 in rodents causes cerebellar cell loss and impaired acquisition of conditioned responses (CRs) during "short-delay" eyeblink classical conditioning (ECC), using optimal (280,350 ms) interstimulus intervals (ISIs). We extended those earlier findings by comparing acquisition of delay ECC under two different ISIs. From PD 4 to 9, rats were intubated with either 5.25 g/kg of ethanol (2/day), sham intubated, or were not intubated. They were then trained either as periadolescents (about PD 35) or as adults (>PD 90) with either the optimal short-delay (280-ms) ISI, a long-delay (880-ms) ISI, or explicitly unpaired CS and US presentations. Neonatal binge ethanol treatment significantly impaired acquisition of conditioning at both ages regardless of ISI, and deficits in the acquisition and expression of CRs were comparable across ISIs. These deficits are consistent with the previously documented ethanol-induced damage to the cerebellar,brainstem circuit essential for Pavlovian ECC. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 589-605, 2007. [source]

    Immature cortical responses to auditory stimuli in specific language impairment: evidence from ERPs to rapid tone sequences

    D.V.M. Bishop
    Event-related potentials (ERPs) to tone pairs and single tones were measured for 16 participants with specific language impairment (SLI) and 16 age-matched controls aged from 10 to 19 years. The tone pairs were separated by an inter-stimulus interval (ISI) of 20, 50 or 150 ms. The intraclass correlation (ICC) was computed for each participant between the ERP to a single tone and the ERP to the tone pair. A high ICC indicates that the brain response to a tone pair is similar to that for a single tone. ICCs were significantly higher at short than at long ISIs. At 50-ms ISI, ICCs were higher for younger than older participants. Age and ISI interacted with SLI status: ERPs of older participants with SLI differed from age-matched controls, and resembled ERPs of younger controls, consistent with a theory of immature auditory processing in SLI. [source]

    Moxonidine improves glycaemic control in mildly hypertensive, overweight patients: a comparison with metformin

    Irina Chazova
    Aim:, To compare the effects of moxonidine and metformin on glycaemic control in patients with impaired glucose tolerance and signs of the metabolic syndrome. Methods:, A multicentre, prospective, randomized, open-label study design was adopted with blinded endpoint evaluation. Patients ,40 years old, with impaired glucose tolerance (or diabetes mellitus treated with diet alone) and a body mass index (BMI) of at least 27 kg/m2 were treated twice daily with moxonidine 0.2 mg or metformin 500 mg for 16 weeks. Oral glucose tolerance test (OGTT) was performed at baseline and end-of-study; plasma insulin and plasma glucose levels were measured at 0, 60, 120 and 180 min after administration. Results:, With regard to effects on insulin [mean area under the curve (AUC) for insulin], the primary efficacy endpoint of the study, both drugs did not show equivalence. On the contrary, in the per protocol (PP) population, moxonidine statistically significantly (p = 0.025) decreased the AUC for insulin from baseline in the PP population; for metformin, the treatment effect on insulin was a small, net increase resulting in a statistically significant between-group difference of 16.2% (95% CI = 0.1,35.0). The change in mean insulin AUC was most marked in the subgroup of patients with higher sympathetic activity (heart rate >80 bpm). Mean fasting plasma glucose (FPG) levels and HbA1c levels were largely unchanged by moxonidine treatment but significantly decreased by metformin treatment. The difference between the groups was 14.7% (p = 0.0523) in the intent-to-treat (ITT) sample. By study end, both treatments had significantly increased the Matsuda Insulin Sensitivity Index (ISI) from baseline to a comparable extent: moxonidine by reducing plasma insulin after a glucose challenge, metformin by reducing FPG. BMI fell significantly in both groups and blood pressure normalized; both drugs were well tolerated. Conclusions:, Moxonidine improved insulin sensitivity in response to glucose challenge in patients with evidence of metabolic syndrome. This improvement resulted from a reduction in plasma insulin levels and was most marked in patients with high sympathetic drive at baseline. By enhancing insulin sensitivity, moxonidine treatment may help prevent the development of diabetes and thereby ameliorate the risk for cardiovascular disease. [source]

    Effects of short-term metformin treatment on insulin sensitivity of blood glucose and free fatty acids

    S. Iannello
    Aim:, Based on the known effect of metformin (MET) in improving insulin sensitivity in type 2 diabetes, with the scope to focus the effects on glycaemic and free fatty acids (FFA) levels, we studied the effects of a short-term treatment with this drug in obese subjects and obese patients with diabetes or family history of diabetes (FHD). We used a method to allow us to evaluate the possible difference of insulin sensibility with regard to the insulin action on glycaemia and blood FFA, both in the basal state and during oral glucose tolerance test (OGTT). Methods:, Insulin sensitivity was investigated before and after MET treatment (850 mg bid for 10 days) in seven obese subjects with normal glucose tolerance and without FHD and 13 obese patients with diabetes (n = 7) or FHD (n = 6). By using specifically designed formulae, we calculated four insulin-sensitivity indices (ISI) from basal level (b) and area values (a) (during OGTT) of insulinaemia, glycaemia (gly) or FFA (ffa), namely: ISI (gly)-b, ISI (gly)-a, ISI (ffa)-b and ISI (ffa)-a. Results:, In patients with diabetes or FHD, MET improved ISI (gly)-b (0.79 ± 0.06 vs. 0.59 ± 0.07, p < 0.001) and ISI (gly)-a (0.69 ± 0.09 vs. 0.51 ± 0.07, p < 0.05), whereas only minor changes occurred for ISI (ffa)-b and ISI (ffa)-a. In contrast, in simple obese subjects, MET induced further deterioration of both ISI (gly)-a (0.47 ± 0.07 vs. 0.64 ± 0.10, p < 0.01) and ISI (ffa)-a (0.43 ± 0.07 vs. 0.55 ± 0.08, p < 0.05). Fasting level and total area of lactate were high in the obese patients and were not affected by MET. A statistically significant increase (p < 0.01), however, was observed for the ,decremental' area of lactate in obese subjects with diabetes or FHD, which might probably contribute to the reduction of insulin resistance induced by the drug in these patients. Conclusions:, Although the low number of subjects studied precludes absolute conclusions, data would suggest that MET improved ISI towards glucose but not towards FFA, in the diabetic and ,prediabetic' obese patients, whereas worsened it in the obese subjects without FHD. Therefore, the effects of MET would not be secondary to changes of FFA but rather to a primary action of MET on glucose metabolism. Thus, utilization of MET to treat the insulin resistance in obesity is indicated only in the presence of alterations of glucose metabolism or FHD. [source]

    Insulin resistance is not coupled with defective insulin secretion in primary hyperparathyroidism

    DIABETIC MEDICINE, Issue 10 2009
    F. Tassone
    Abstract Aims, An increased frequency of both impaired glucose tolerance and Type 2 diabetes mellitus (DM) has been reported in primary hyperparathyroidism (pHPT), thus we sought to investigate insulin sensitivity and insulin secretion in a large series of pHPT patients. Subjects and methods, One hundred and twenty-two consecutive pHPT patients without known DM were investigated [age (mean ± sd) 59.3 ± 13.6 years, body mass index (BMI) 25.7 ± 4.2 kg/m2; serum calcium 2.8 ± 0.25 mmol/l; PTH 203.2 ± 145.4 ng/l]. Sixty-one control subjects were matched, according to the degree of glucose tolerance, in a 2 : 1 patient:control ratio. Fasting- and oral glucose tolerance test-derived estimates of insulin sensitivity and secretion were determined by means of the quantitative insulin sensitivity check index (QUICKI) and the insulin sensitivity index (ISI) composite. Results, Both the QUICKI and ISI composite were lower in pHPT patients than control subjects (P < 0.03 and P < 0.05, respectively) after adjusting for age, systolic blood pressure and BMI. Conversely, all insulin secretion estimates were significantly increased in pHPT patients than in control subjects (P < 0.04 and P < 0.03, respectively) and after adjusting for age, systolic blood pressure and BMI. Log serum calcium levels were negatively associated with the QUICKI and log ISI composite (R = ,0.30, P = 0.001; R = ,0.23, P = 0.020, respectively) in pHPT patients. Serum calcium levels significantly and independently contributed to impaired insulin sensitivity in multivariate analysis (QUICKI as dependent variable: , = ,0.31, P = 0.004, R2 = 0.15; log ISI composite as dependent variable: , = ,0.29, P = 0.005, R2 = 0.16). Conclusions, Our study confirms a reduction in both basal and stimulated insulin sensitivity in primary hyperparathyroidism, in spite of increased insulin secretion. Moreover, our data show for the first time a significant relationship between hypercalcaemia and insulin sensitivity in this condition. [source]

    Review of validation studies of the Edinburgh Postnatal Depression Scale

    Malin Eberhard-Gran
    Objective: ,To review validation studies of the Edinburgh Postnatal Depression Scale (EPDS). Method: ,A systematic search was performed in Medline and the Science Citation Index Expanded (ISI) from the period 1987,2000. For sensitivity and specificity of the EPDS presented in each study, 95% confidence intervals were estimated. Positive and negative predictive values were estimated assuming prevalences of postpartum depression ranging from 5% to 20%. Results: ,Eighteen validation studies were identified. The study design varied between studies. The sensitivity and specificity estimates also varied: 65,100% and 49,100%, respectively. The confidence intervals were estimated to be wide. Our estimates suggest a lower positive predictive value in a normal population than in the validation study samples. Conclusion: ,Most studies show a high sensitivity of the EPDS. Because of the differences in study design and large confidence intervals, uncertainty remains regarding the comparability between the sensitivity and specificity estimates of the different EPDS versions. [source]

    Auditory temporal processing deficits in children with reading disabilities

    DYSLEXIA, Issue 3 2007
    Ravit Cohen-Mimran
    Abstract The role of central auditory processing in reading skill development and reading disorders is unclear. The purpose of this study was to examine whether individuals with specific reading disabilities (SRD) have deficits in processing rapidly presented, serially ordered non-speech auditory signals. To this end, we compared 12 children with SRD and 12 children without SRD on their ability to detect differences and similarities in pure tones of 1000 and 2000 Hz when these signals were presented in pairs (same or different tones, randomly ordered) with short (50 ms) versus long (500 ms) inter stimulous intervals (ISI). Results showed that the children with SRD had significant difficulty in discriminating between pure tones with short, but not long ISI, whereas the controls performed well with both short and long ISI. The two groups did not differ significantly on measures of attention (d2) and performance IQ, and there were no significant correlations between these measures and ISI performance. There were significant correlations between the short ISI performance and phonologic awareness test results when the two groups were combined. These findings support the specific rapid auditory processing deficit hypothesis of SRD. Examination of intra-subject variability in performance indicated that children from the SRD group showed both decrement in performance with time on task and high overall variability in performance as compared to the controls. These findings underpin the importance of using time-series analyses of performance. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Load-Adaptive MUI/ISI-Resilient Generalized Multi-Carrier CDMA with Linear and DF Receivers

    Georgios B. Giannakis
    A plethora of single-carrier and multi-carrier (MC) CDMA systems have been proposed recently to mitigate intersymbol interference (ISI) and eliminate multiuser interference (MUI). We present a unifying all-digital Generalized Multicanier CDMA framework which enables us to describe existing CDMA schemes and to highlight thorny problems associated with them. To improve the bit error rate (BER) performance of existing schemes, we design block FIR transmitters and decision feedback (DF) receivers based on an inner-code/outer-code principle, which guarantees MUI/ISI-elimination regardless of the frequency-selective physical channel. The flexibility of our framework allows further BER enhancements by taking into account the load in the system (number of active users), while blind channel estimation results in bandwidth savings. Simulations illustrate the superiority of our framework over competing MC CDMA alternatives especially in the presence of uplink multipath channels. [source]

    The Impact of Trade Liberalization on Regional Disparities in Mexico

    GROWTH AND CHANGE, Issue 1 2002
    Javier Sánchez-Reaza
    After a long period of industrialization based on import substitution (ISI), Mexico started to open up its economy by accessing the General Agreement on Tariffs and Trade (GATT) in 1986. The export-promotion strategy was transformed into one of regional integration with the signing of the North American Free Trade Agreement (NAFTA) in 1994. The paper explores the impact of the opening of the economy on regional disparities in Mexico using , and ,-convergence analyses. Four different samples have been employed to control for possible data bias linked to the inclusion of oil-producing and maquiladora-based states. The results show that whereas the final stages of the ISI period were dominated by convergence trends, trade liberalization (GATT) and economic integration (NAFTA) have led to divergence. In particular, the NAFTA period is related to divergence regardless of the type of analysis chosen and the sample used. [source]

    Change of Excitability in Brainstem and Cortical Visual Processing in Migraine Exhibiting Allodynia

    HEADACHE, Issue 10 2006
    Koichi Shibata MD
    Background.,Clinical and neurophysiological manifestations of information processing associated with central sensitization are little known. Allodynic migraine (AM) can be caused by the sensitization of trigeminal neuron, but no study has reported on AM between attacks using blink reflex (BR) and pattern-reversal visual evoked potentials (PVEPs). Objective.,We explored the characteristics of AM between attacks associated with central sensitization using BR and PVEP. Methods.,We recruited 13 patients with interictal AM and 15 patients with nonallodynic migraine (NA), and 30 healthy subjects (HS). BRs were obtained using paired pulses delivered at the interstimulus interval (ISI) of 150, 300, and 500 ms. The ratio of the area in the R2 of the second to R2 of the first shock was measured for each ISI. PVEP were recorded with 2 spatial frequencies (0.5 and 4.0 cpd) and 2 low and high contrasts (29% and 98%, respectively). Amplitudes of P100 were measured. Results.,For BR, there were no significant differences in the ratio of the area of the R2 between the sides of stimulation, and the sides of headache. AM patients had less suppression of the R2 at the ISI of 150 and 300 ms when compared with the NA patients and HS. For PVEP, at 0.5, there were significant differences of amplitude between AM patients and HS, and between NA patients and HS in low and high contrast. At 4.0 cpd, there were significant differences of amplitude between AM patients and HS in low contrast, and between AM patients and HS, and NA patients and HS in high contrast. In AM patients, there was a significant difference of amplitude ratio between 0.5 and 4.0 cpd. Conclusions.,Our BR and PVEP study showed that migraine patients exhibiting allodynia may show central sensitization of brainstem trigeminal neuron and have contrast modulating dysfunction during the cortical visual processing of striate and extrastriate on visual cortex in-between attacks. [source]

    Downloads and citations in Intelligent Systems in Accounting, Finance and Management

    Daniel E. O'Leary
    This paper summarizes the papers downloaded most from the years 2000,2002 and traces the number of citations from Google Scholar (beta) for those papers at the beginning of 2008. It is found that the number of downloads and citations are highly correlated, suggesting that downloads is a leading indicator of citations, even years into the future. In addition, this paper assesses which of the papers from the journal have been cited most over the history of the journal, using both ISI,Social Science Citation Index and Google Scholar. It is found that the numbers of citations using both approaches are highly correlated. Copyright © 2009 John Wiley & Sons, Inc. [source]

    Performance analysis of adaptive receivers for DS/CDMA communication systems

    Fang-Biau Ueng
    Abstract Both intersymbol interference (ISI) and multiple-access interference (MAI) are the important issues in code division multiple access (CDMA) multiuser communication systems. The step size of the traditional least-mean-square (LMS) adaptive receivers must be substantially adjusted to overcome the effect due to different channel responses or different numbers of active users. The normalized-LMS (NLMS) algorithm can automatically manipulate the adjustment to avoid the problem just discussed. This paper proposes the symbol-based interference rejection filter with NLMS algorithm and derives both finite impulse response (FIR)- and infinite impulse response (IIR)-type algorithms. We also derive the optimal step sizes and minimum mean-square errors (MSEs) for both the FIR and IIR symbol-based receivers. The complexity of our proposed FIR receiver is lower than that of the conventional chip-based receivers. In addition, it is shown that the bit error rate performance of our proposed symbol-based receivers is superior to conventional one in the simulations. Simulations also show the correctness of our theoretical analysis of minimum MSE. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Oral health-related quality of life in children: Part I. How well do children know themselves?

    A systematic review
    Abstract:, Objective:, Paediatric oral disorders are likely to have a negative effect on the quality of life. Until recently, children's oral health-related quality of life (OHRQoL) was measured using parents as informants. Instruments have now been developed, which have demonstrated that with appropriate questionnaire techniques, valid and reliable information can be obtained from children. The aim of this study was to make a systematic review of the existing literature about child perceptions of OHRQoL and their validation. Methods:, A computerized search was conducted using Medline, ISI, Lilacs and Scielo for children's perception of OHRQoL. The inclusion criteria were: the articles should contain well-validated instruments and provide child perceptions of OHRQoL. Results:, From 89 records found, 13 fulfilled the criteria. All studies included in the critical appraisal of the project suggested good construct validity of overall child perceptions of OHRQoL. However, children's understanding of oral health and well-being are also affected by variables (age, age-related experiences, gender, race, education, culture, experiences related to oral conditions, opportunities for treatment, childhood period of changes, back-translating questionnaire, children self-perceived treatment need). Conclusions:, The structure of children's self-concept and health cognition is age-dependent as a result of their continuous cognitive, emotional, social and language development. By using appropriate questionnaire techniques, valid and reliable information can be obtained from children concerning their OHRQoL. [source]

    Antidiabetic activity of flavone from Ipomoea Batatas leaf in non-insulin dependent diabetic rats

    Rui Zhao
    Summary The effects of flavone extracted from Ipomoea batatas leaf (FIBL) on body weight, blood glucose, serum lipid profiles, serum insulin and free radicals in rats with non-insulin dependent diabetes mellitus (NIDDM) were studied. FIBL treatment (25, 50, 100 mg kg,1) for 2 weeks resulted in a significant decrease in the concentration of plasma triglyceride (TG), plasma cholesterol (TC) and weight in NIDDM rats. Furthermore, FIBL markedly decreased fasting plasma insulin level, blood glucose (FBG) level, low-density lipoprotein cholesterol (LDL-C), and malondialdehyde (MDA) levels and significantly increased the Insulin Sensitive Index (ISI) and superoxide dismutase (SOD) level in NIDDM rats. In addition, flavone extracted from I. batatas leaf did not show any physical or behavioural signs of toxicity. More significantly, our data demonstrate the FIBL at the dose of 50 mg kg,1 body weight exhibited the optimal effect. The above results suggest that flavone extracted from I. batatas leaf could control blood glucose and modulate the metabolism of glucose and blood lipid, and decrease outputs of lipid peroxidation and scavenge the free radicals in non-insulin dependent diabetic rats. [source]

    Crucial Issues for Statistics in the Next Two Decades

    Nicholas I. Fisher
    Summary This collection of articles stems from an Invited Paper meeting at the 52nd Session of the ISI in Helsinki, August 1999. The purpose of the session was to explore issues likely to be critical to the long-term survival of the discipline, if not the profession, of Statistics. The contributors in the session have all made outstanding contributions to both the theory and practice of Statistics, and have also had an ongoing interest in the long-term development of the subject. Subsequently, they were given the opportunity to elaborate on their contributions, for wider dissemination. [source]

    Prevalence and correlates of clinical insomnia co-occurring with chronic back pain

    Summary Given the suggestion of a reciprocal relationship between sleep and pain and the recognition of sleep as an important parameter in determining quality of life, there is increasing research interest in sleep disturbance linked to chronic pain. The present study aimed to provide an estimate of the prevalence of ,clinical insomnia' in patients attending a specialist pain clinic and identify factors associated with it. Seventy chronic back pain patients and 70 gender- and age-matched pain-free controls completed a set of questionnaires measuring sleep (Insomnia Severity Index; ISI), pain (Short-Form McGill Pain Questionnaire) and a selection of general and specific psychological variables (Hospital Anxiety and Depression Scale, Short Health Anxiety Inventory). Scores suggestive of clinical insomnia (ISI , 15) were noted in 53% of chronic pain patients, when compared with only 3% in pain-free controls. Significant positive correlations with insomnia severity were detected for all six variables of interest (pain intensity, sensory pain ratings, affective pain ratings, general anxiety, general depression and health anxiety). Affective pain ratings and health anxiety were the best predictors of insomnia severity in this sample, accounting for 30% of the total variance, even when present pain intensity was controlled for. Affective pain remained as a significant predictor of insomnia severity when both the effect of pain intensity and the effects of anxiety and depression were controlled for. Future research should consider investigating the role of pain appraisal and health anxiety in the development and manifestation of insomnia concomitant to chronic pain. [source]

    Google book search: Citation analysis for social science and the humanities

    Kayvan Kousha
    In both the social sciences and the humanities, books and monographs play significant roles in research communication. The absence of citations from most books and monographs from the Thomson Reuters/Institute for Scientific Information databases (ISI) has been criticized, but attempts to include citations from or to books in the research evaluation of the social sciences and humanities have not led to widespread adoption. This article assesses whether Google Book Search (GBS) can partially fill this gap by comparing citations from books with citations from journal articles to journal articles in 10 science, social science, and humanities disciplines. Book citations were 31% to 212% of ISI citations and, hence, numerous enough to supplement ISI citations in the social sciences and humanities covered, but not in the sciences (3%,5%), except for computing (46%), due to numerous published conference proceedings. A case study was also made of all 1,923 articles in the 51 information science and library science ISI-indexed journals published in 2003. Within this set, highly book-cited articles tended to receive many ISI citations, indicating a significant relationship between the two types of citation data, but with important exceptions that point to the additional information provided by book citations. In summary, GBS is clearly a valuable new source of citation data for the social sciences and humanities. One practical implication is that book-oriented scholars should consult it for additional citations to their work when applying for promotion and tenure. [source]

    Comparing bibliometric statistics obtained from the Web of Science and Scopus

    Éric Archambault
    For more than 40 years, the Institute for Scientific Information (ISI, now part of Thomson Reuters) produced the only available bibliographic databases from which bibliometricians could compile large-scale bibliometric indicators. ISI's citation indexes, now regrouped under the Web of Science (WoS), were the major sources of bibliometric data until 2004, when Scopus was launched by the publisher Reed Elsevier. For those who perform bibliometric analyses and comparisons of countries or institutions, the existence of these two major databases raises the important question of the comparability and stability of statistics obtained from different data sources. This paper uses macrolevel bibliometric indicators to compare results obtained from the WoS and Scopus. It shows that the correlations between the measures obtained with both databases for the number of papers and the number of citations received by countries, as well as for their ranks, are extremely high (R2 , .99). There is also a very high correlation when countries' papers are broken down by field. The paper thus provides evidence that indicators of scientific production and citations at the country level are stable and largely independent of the database. [source]

    How are new citation-based journal indicators adding to the bibliometric toolbox?

    Loet Leydesdorff
    The launching of Scopus and Google Scholar, and methodological developments in social-network analysis have made many more indicators for evaluating journals available than the traditional impact factor, cited half-life, and immediacy index of the ISI. In this study, these new indicators are compared with one another and with the older ones. Do the various indicators measure new dimensions of the citation networks, or are they highly correlated among themselves? Are they robust and relatively stable over time? Two main dimensions are distinguished,size and impact,which together shape influence. The h-index combines the two dimensions and can also be considered as an indicator of reach (like Indegree). PageRank is mainly an indicator of size, but has important interactions with centrality measures. The Scimago Journal Ranking (SJR) indicator provides an alternative to the journal impact factor, but the computation is less easy. [source]

    Eigenfactor: Does the principle of repeated improvement result in better estimates than raw citation counts?

    Philip M. Davis, a journal evaluation tool that uses an iterative algorithm to weight citations (similar to the PageRank algorithm used for Google), has been proposed as a more valid method for calculating the impact of journals. The purpose of this brief communication is to investigate whether the principle of repeated improvement provides different rankings of journals than does a simple unweighted citation count (the method used by the Institute for Scientific Information@ [ISI]). [source]

    Assessing an author's influence using time series historiographic mapping: The oeuvre of conrad hal waddington (1905,1975)

    Katherine W. McCain
    A modified approach to algorithmic historiography is used to investigate the changing influence of the work of Conrad Hal Waddington over the period 1945,2004. Overall, Waddington's publications were cited by almost 5,500 source items in the Web of Science (Thomson Scientific, formerly Thomson ISI, Philadelphia, PA). Rather than simply analyzing the data set as a whole, older works by Waddington are incorporated into a series of historiographic maps (networks of highly cited documents), which show long-term and short-term research themes grounded in Waddington's work. Analysis by 10,20-year periods and the use of social network analysis soft- ware reveals structures,thematic networks and subnetworks,that are hidden in a mapping of the entire 60-year period. Two major Waddington-related themes emerge,canalization/genetic assimilation and embryonic induction. The first persists over the 60 years studied while active, visible research in the second appears to have declined markedly between 1965 and 1984, only to reappear in conjunction with the emergence of a new research field,Evolutionary Developmental Biology. [source]

    The place of serials in referencing practices: Comparing natural sciences and engineering with social sciences and humanities

    Vincent Larivičre
    Journal articles constitute the core documents for the diffusion of knowledge in the natural sciences. It has been argued that the same is not true for the social sciences and humanities where knowledge is more often disseminated in monographs that are not indexed in the journal-based databases used for bibliometric analysis. Previous studies have made only partial assessments of the role played by both serials and other types of literature. The importance of journal literature in the various scientific fields has therefore not been systematically characterized. The authors address this issue by providing a systematic measurement of the role played by journal literature in the building of knowledge in both the natural sciences and engineering and the social sciences and humanities. Using citation data from the CD-ROM versions of the Science Citation Index (SCI), Social Science Citation Index (SSCI), and Arts and Humanities Citation Index (AHCI) databases from 1981 to 2000 (Thomson ISI, Philadelphia, PA), the authors quantify the share of citations to both serials and other types of literature. Variations in time and between fields are also analyzed. The results show that journal literature is increasingly important in the natural and social sciences, but that its role in the humanities is stagnant and has even tended to diminish slightly in the 1990s. Journal literature accounts for less than 50% of the citations in several disciplines of the social sciences and humanities; hence, special care should be used when using bibliometric indicators that rely only on journal literature. [source]

    User acceptance of Intelligence and Security Informatics technology: A study of COPLINK

    Paul Jen-Hwa Hu
    The importance of Intelligence and Security Informatics (ISI) has significantly increased with the rapid and large-scale migration of local/national security information from physical media to electronic platforms, including the Internet and information systems. Motivated by the significance of ISI in law enforcement (particularly in the digital government context) and the limited investigations of officers' technology-acceptance decision-making, we developed and empirically tested a factor model for explaining law-enforcement officers' technology acceptance. Specifically, our empirical examination targeted the COPLINK technology and involved more than 280 police officers. Overall, our model shows a good fit to the data collected and exhibits satisfactory power for explaining law-enforcement officers' technology acceptance decisions. Our findings have several implications for research and technology management practices in law enforcement, which are also discussed. [source]

    Firm-like behavior of journals?

    Scaling properties of their output, impact growth dynamics
    In the study of growth dynamics of artificial and natural systems, the scaling properties of fluctuations can exhibit information on the underlying processes responsible for the observed macroscopic behavior according to H.E. Stanley and colleagues (Lee, Amaral, Canning, Meyer, & Stanley, 1998; Plerou, Amaral, Gopikrishnan, Meyer, & Stanley, 1999; Stanley et al., 1996). With such an approach, they examined the growth dynamics of firms, of national economies, and of university research fundings and paper output. We investigated the scaling properties of journal output and impact according to the Journal Citation Reports (JCR; ISI, Philadelphia, PA) and find distributions of paper output and of citations near to lognormality. Growth rate distributions are near to Laplace "tents," however with a better fit to Subbotin distributions. The width of fluctuations decays with size according to a power law. The form of growth rate distributions seems not to depend on journal size, and conditional probability densities of the growth rates can thus be scaled onto one graph. To some extent even quantitatively, all our results are in agreement with the observations of Stanley and others. Further on, a Matthew effect of journal citations is confirmed. If journals "behave" like business firms, a better understanding of Bradford's Law as a result of competition among publishing houses, journals, and topics suggests itself. [source]

    Recollections of Irving H. Sher 1924,1996: Polymath/information scientist extraordinaire

    Eugene Garfield
    Over a 35-year period, Irving H. Sher played a critical role in the development and implementation of the Science Citation Index® and other ISI® products. Trained as a biochemist, statistician, and linguist, Sher brought a unique combination of talents to ISI as Director of Quality Control and Director of Research and Development. His talents as a teacher and mentor evoked loyalty. He was a particularly inventive but self-taught programmer. In addition to the SCI,® Social Sciences Citation Index,® and Arts and Humanities Citation Index,® Sher was involved with the development of the first commercial SDI system, the Automatic Subject Citation Alert, now called Research Alert,® and Request-A-Print Cards. Together we developed the journal impact factor and the Journal Citation Reports.® Sher was also the inventor of the SYSTABAR System of coding references and Sherhand. He was involved in key reports on citation-based historiography, forecasting Nobel prizes, and served as a referee for JASIS over a 20-year period. [source]

    Comparison of local International Sensitivity Index calibration and ,Direct INR' methods in correction of locally reported International Normalized Ratios: an international study

    Summary.,Background:,It is no longer feasible to check local International Normalized Ratios (INR) by the World Health Organization International Sensitivity Index (ISI) calibrations because the necessary manual prothrombin time technique required has generally been discarded. Objectives:,An international collaborative study at 77 centers has compared local INR correction using the two alternative methods recommended in the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis guidelines: local ISI calibration and ,Direct INR'. Methods:,Success of INR correction by local ISI calibration and with Direct INR was assessed with a set of 27 certified lyophilized plasmas (20 from patients on warfarin and seven from normals). Results:,At 49 centers using human thromboplastins, 3.0% initial average local INR deviation from certified INR was reduced by local ISI calibration to 0.7%, and at 25 centers using rabbit reagents, from 15.9% to 7.5%. With a minority of commercial thromboplastins, mainly ,combined' rabbit reagents, INR correction was not achieved by local ISI calibration. However, when rabbit combined reagents were excluded the overall mean INR deviation after correction was reduced further to 3.9%. In contrast, with Direct INR, mean deviation using human thromboplastins increased from 3.0% to 6.6%, but there was some reduction with rabbit reagents from 15.9% to 10% (12.3% with combined reagents excluded). Conclusions:,Local ISI calibration gave INR correction for the majority of PT systems but failed at the small number using combined rabbit reagents suggesting a need for a combined reference thromboplastin. Direct INR correction was disappointing but better than local ISI calibration with combined rabbit reagents. Interlaboratory variability was improved by both procedures with human reagents only. [source]


    METROECONOMICA, Issue 3 2010
    Article first published online: 10 NOV 200, Roberto Tamborini
    ABSTRACT Financial instability is the new challenge for monetary policy. Most studies indicate that financial crises follow prolonged unwinding of investment,saving imbalances (ISI). These phenomena are not contemplated by the standard theoretical framework of continuous intertemporal equilibrium. This paper's aim is to take a first step into the analysis of monetary policy in the context of ISI. First, a dynamic model of a flex-price, competitive economy is presented where ISI are allowed to develop. Second, upon introducing different types of Taylor rules, some indications for the conduct of monetary policy emerge, which are at variance with the standard view. [source]

    Somatosensory disinhibition in dystonia

    MOVEMENT DISORDERS, Issue 4 2001
    Emma Frasson MD
    Abstract Despite the fact that somatosensory processing is inherently dependent on inhibitory functions, only excitatory aspects of the somatosensory feedback have so far been assessed in dystonic patients. We studied the recovery functions of spinal N13, brainstem P14, parietal N20, P27, and frontal N30 somatosensory evoked potentials (SEPs) after paired median nerve stimulation in 10 patients with dystonia and in 10 normal subjects. The recovery functions were assessed (conditioning stimulus: S1; test stimulus: S2) at interstimuls intervals (ISIs) of 5, 20, and 40 ms. SEPs evoked by S2 were calculated by subtracting the SEPs of the S1 only response from the SEPs of the response to the paired stimuli (S1 + S2), and their amplitudes were compared with those of the control response (S1) at each ISI considered. This ratio, (S2/S1)*100, investigates changes in the excitability of the somatosensory system. No significant difference was found in SEP amplitudes for single stimulus (S1) between dystonic patients and normal subjects. The (S2/S1)*100 ratio at the ISI of 5 ms did not significantly differ between dystonic patients and normal subjects, but at ISIs of 20 and 40 ms, this ratio was significantly higher in patients than in normals for spinal N13 and cortical N20, P27, N30 SEPs. These findings suggest that in dystonia there is an impaired inhibition at spinal and cortical levels of the somatosensory system which would lead to an abnormal sensory assistance to the ongoing motor programs, ultimately resulting in the motor abnormalities present in this disease. © 2001 Movement Disorder Society. [source]