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1.
Seeber  Marco 《Scientometrics》2020,122(3):1387-1405
Scientometrics - Current knowledge on peer review consists of general formulations of its goals and micro level accounts of its practice, while journals’ attempts to guide and shape peer...  相似文献   
2.
Patients with non-cardiac chest pain (NCCP) (n = 387) and cardiac chest pain (CCP) (n = 93) were compared with community controls (n = 81), using a symptom questionnaire that assessed the presence of irritable bowel syndrome (IBS), functional dyspepsia, and oesophageal dysfunction and chest pain characteristics. A significantly (p < 0.05) increased prevalence of symptoms compatible with IBS occurred in NCCP patients when compared with those with CCP and with controls. Dysphagia was more frequent in both those with non-cardiac and cardiac chest pain than in controls; this was not apparent, however, when patients with concomitant IBS were excluded. The presence of oesophageal or gastrointestinal symptoms did not enable discrimination with regard to the chest pain characteristics. We conclude that unselected referred patients with documented NCCP are more likely to have IBS and that the presence of oesophageal symptoms such as dysphagia may merely reflect the spectrum of the 'irritable gut'.  相似文献   
3.
The aim of this paper is to empirically test whether interlinking patterns between higher education institutions (HEIs) conform to a document model, where links are motivated by webpage content, or a social relationship model, where they are markers of underlying social relationships between HEIs. To this aim, we analyzed a sample of approximately 400 European HEIs, using the number of pages on their web domains and the total number of links sent and received; in addition we test whether these two characteristics are associated with organizational size, reputation, and the volume of teaching and research activities. Our main findings are as follows: first, the number of webpages of HEI websites is strongly associated with their size, and to a lesser extent, with the volume of their educational activities, research orientation, and reputation; differences between European countries are rather limited, supporting the insight that the academic Web has reached a mature stage. Second, the distribution of connectivity (as measured by the total degree of HEI’s) follows a lognormal distribution typical of social networks between organizations, while counts of weblinks can be predicted with good precision from organizational characteristics. HEIs with larger websites tend to send and receive more links, but the effect is rather limited and does not fundamentally modify the resulting network structure. We conclude that aggregated counts of weblinks between pairs of HEIs are not significantly affected by the web policies of HEIs and thus can be considered as reasonably robust measures. Furthermore, interlinking should be considered as proxies of social relationships between HEIs rather than as reputational measures of the content published on their websites.  相似文献   
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The ability of rats to learn the location of a hidden platform in a swim maze was compared in animals with excitotoxic lesions of the anterior or posterior (retrosplenial) cingulate cortex or radiofrequency lesions of the cingulum bundle or fimbria-fornix. Performance of this allocentric spatial task was unaffected by the posterior cingulate cortex lesions, while anterior cingulate cortex damage produced only a mild acquisition deficit. Transection of the fornix and lesions of the cingulum bundle produced similar patterns of impairment on initial acquisition, but the cingulum bundle lesions had less effect on reversal of the task. The results from the water maze, and from a subsequent T-maze alternation task, indicate that cingulum bundle lesions can produce a spatial deficit that is similar, but milder, to that observed after fornix transection. The results of the excitotoxic lesions suggest that previous studies examining conventional cingulate lesions may have been influenced by damage to adjacent fibre tracts, such as the cingulum bundle.  相似文献   
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A new ternary molybdenum chalcogenide has been found with composition InxMo15Se19. This compound crystallizes in the hexagonal space group P63/m, and shows both types of blocks Mo6Se8 and Mo9Se11. To our knowledge, this is the first Me9X11 unit ever observed in a material. It presents a homogeneity domain: 2, 9 < x < 3, 4. Substitution of sulphur and tellurium for selenium in In3.3Mo15Se19-yXy (X = S, Te) is possible in the limits 0 < y < 12 and 0 < y < 2 respectively. The new compound becomes a high field superconductor at low temperature.  相似文献   
8.
The present paper outlines the association of biochemical and subjective indicators of alcohol consumption. Due to its relevance as a potential confounding variable in occupational neurotoxicology, both sources of information about drinking habits were related to neurobehavioral test performance. A sample of 308 rotogravure printers and control subjects from a cross-sectional longitudinal study in various German printing plants was studied. Duration of employment was 4 months to 44 years (mean = 14.9, sd = 9.67). Mean age was 38.4 years (range 21 - 60). From venous blood samples three parameters considered to be sensitive for increased consumption of alcohol were used. They were carbohydrate-deficient transferrin (CDT), gamma glutamyl transferase (GGT), and mean cell volume (MCV). During the medical interview subjects with any chronic liver disease were identified and excluded from data analysis. Additionally, information about weekly consumption of alcohol was assessed and transformed to grams per day (g/d) values. Neurobehavioral testing included simple reaction time (SPES version), switching attention, symbol digit substitution, and digit span (EURONEST version). Additionally, a questionnaire of neurotoxic complaints was administrated. Other covariates, i.e. verbal ability, history of solvent exposure, and age were controlled. GGT and CDT were elevated in 10.5% and 6.6% of the population. 3.5% of the subjects reported daily consumption higher than 60 gram. There were positive correlations of CDT and GGT with the subjective indicator of drinking habits. The magnitude of these relationships were low, but the associations were significant. MCV was not correlated with subjective reports of drinking habits, but it showed convergent correlations with CDT and GGT. Comparison of these two parameters with performance on neurobehavioral tasks yielded only one negative association, i.e. between the memory-loaded tasks factor and GGT. CDT and subjective estimation of alcohol consumption were not related to any cognitive function tested in this study. Especially, the digits-backward task was negatively correlated with increased GGT.  相似文献   
9.
A full-length cDNA of the filarial nematode Acanthocheilonema viteae was isolated from a cDNA library of female worms, using a partial cDNA of the OvL3-1 gene of Onchocerca volvulus as a probe. The AvL3-1 cDNA contained an open reading frame which encoded for a protein with a theoretical molecular weight of 64 kDa. The deduced protein contained a predicted signal sequence, a short repetitive motive of unknown function, and three LIM domains. The structure of the LIM domains was identical to those of zyxin, a cytoskeleton-associated protein of chicken fibroblasts, suggesting that AvL3-1 has a similar role in filarial nematodes. The sequence information was used to isolate the homologous cDNA of O. volvulus by PCR from a cDNA library of female O. volvulus, which showed an overall identity of 76.9% to AvL3-1 on the protein level. AvL3-1 was expressed in Escherichia coli and the affinity-purified fusion free protein was used to immunized jirds (Meriones unguiculatus). Immunization together with the adjuvant STP or with Freund's adjuvant induced IgG and IgM antibody responses, but no significant protection against a challenge infection with L3 of A. viteae, compared to appropriate control groups.  相似文献   
10.
The electrochemical behaviour of chlorinated phenols on Pt/poly(3,4-ethylenedioxy)thiophene,LiClO4 and on Pt/poly(3,4-ethylenedioxy)thiophene,poly(sodium-4-styrenesulphonate) electrodes has been investigated in phosphate buffer solution. Poly(sodium-4-styrenesulphonate) exerts remarkable effect against the electrode fouling induced by oxidation of chlorophenols, allowing us to record the relevant anodic response even after repeated potential cycles. Hypotheses about the role exerted by poly(sodium 4-styrenesulphonate) are made, on the basis of evidences provided by several techniques, such as cyclic voltammetry, electrochemical impedance spectroscopy, electrochemical microgravimetry and atomic force microscopy. Thanks to the fact that different chlorophenols show differences in the voltammetric responses, depending on number and position of the chloro substituents on the aromatic ring, applications of the modified electrode in the analysis of mixtures of chlorinated phenols are possible.  相似文献   
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