186,256 research outputs found
Synthesis, Electronic Structure, and Reactivity of a Planar Four‐Coordinate, Cobalt–Imido Complex
No full textA four-coordinate cobalt-imido complex, ((tBu)mPNP)Co=NMes ((tBu)mPNP=modified PNP pincer ligand) has been synthesized from addition of 2,4,6-trimethylphenylazide (Mes-N-3) to the corresponding dinitrogen complex. The solid-state structure determined by X-ray diffraction established a rare, idealized planar geometry with a Co=N bond distance of 1.716(2) angstrom. Magnetic measurements revealed an S=1 ground state with CAS-SCF calculations supporting radical character on the imide nitrogen. Thermolysis of the cobalt-imido compound induced selective insertion of the imido group into a Co-P bond and yielded a three-coordinate cobalt complex with a distorted T-shaped geometry. Transition state analysis conducted with DFT calculations established the thermodynamic stability of the P-N coupled product and provided insight into the exclusive selectivity.
Behavior of pseudomonas aeruginosa and enterobacter aerogenes in water from filter jugs
No full textCareless use conditions of filter jugs were applied to simulate and evaluate the behavior of two ubiquitous aquatic bacterial species, Pseudomonas aeruginosa and Enterobacter aerogenes. According to a reference protocol, nine different jugs of popular brands sold in the Italian market were used for the test. Separately, a suspension of the two bacteria was spiked in water used for filling the jugs. The concentration of the test organisms and total aerobic microbial count (TAMC) was measured daily in the filtered water along a period corresponding to the cartridge lifetime. Results showed a different trend of bacterial behavior. E. aerogenes was detectable exclusively on the first day after jug filling, while P. aeruginosa confirmed its persistence over time in all the jugs and its ability to potentially colonize surfaces and cartridges. The TAMC was detected at a concentration range from 102 to 107 CFU/100 mL in all the tests, high values that were not far from those raised in bottled flat natural mineral water weeks after bottling
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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
Remarkable harvestmen from the Czech Republic
No full textThe fauna of harvestmen of the Czech Republic is relatively well-known (SILHAVY 1956, MARTENS 1978). Still, species new for the country have recently been found both in natural (KLlMES & BEZDECKA 1995) and synanthropic habitats (KLlMES 1995). Our knowledge of the distribution of most species is, however, far from complete. For several species, including ones found relatively frequently, only a few localities have been reported from the Czech Republic up to now. In this paper we present some interesting findings of harvestmen in Bohemia (western Czech Republic) and Moravia (eastern part) which may stimulate further faunistic research in the territory (fig. 1)
Survival of different microbial strains in pure and diluted tattoo inks
No full textSeveral microorganisms can be found in tattoo inks injected into the skin, despite the ink matrix being considered inhospitable to microbial growth. Studies on the microbial quality of tattoo inks have reported the presence of microorganisms in most of the samples. This study aimed to assess the survival of environmental and human microbial species, selected on the specific criteria, in tattoo inks. Undiluted sterile black ink and serial dilutions (10-fold/100-fold) were each separately seeded with four bacterial strains (Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus pumilus, Mycobacterium fortuitum), one yeast (Candida albicans), and one mould (Fusarium solani). Their survival was periodically tested using cultural methods. No tested microorganisms were able to survive in undiluted ink, except for B. pumilus that survived up to 3 weeks. All the tested species, except for S. aureus, showed survivability for up to 10 weeks in 100-fold diluted inks, and P. aeruginosa, M. fortuitum, and C. albicans were even able to grow. B. pumilus and F. solani had good rates of survival even at the smallest dilution. The ability of microorganisms to survive and grow in tattoo inks could have health implications if contaminated ink dilutions are used during tattooing practices and stored for a long time
An unusual case of fatty liver in a patient with desmoid tumor
No full textA desmoid tumor, also known as aggressive fibromatosis, is a rare benign neoplasm that arises from fascial or musculoaponeurotic tissues. It can occur in any anatomical location, most commonly the abdominal wall, shoulder girdle and retroperitoneum. The typical clinical presentation is a painless mass with a slow and progressive invasion of contiguous structures. It is associated with a high local recurrence rate after resection. Many issues regarding the optimal treatment of desmoid tumors remain controversial. Aggressive surgical resection with a wide margin (2-3 cm) remains the gold standard treatment with regard to preserving quality of life. Radiotherapy alone has been shown to be effective for the control of unresectable or recurrent lesions. Desmoid tumors tend to be locally infiltrative, therefore, the fields must be generous to prevent marginal recurrence. The radiation dose appropriate for treating desmoid tumors remains controversial. We present a 25-year-old Caucasian man with local recurrence of a desmoid tumor after repeated surgical resection, treated with radiotherapy. The patient achieved complete tumor regression at 4 mo after radiotherapy, and he is clinically free of disease at 12 mo after the end of treatment, with an acceptable quality of life. The patient developed short bowel syndrome as a complication of second surgical resection. Consequently, radiotherapy might have worsened an already present malabsorption and so led to steatohepatitis
Indagini in vitelli da carne vaccinati con mutanti termosensibili dei virus parainfluenza-3 (PI-3), rinotracheite infettiva (IBR) e adenovirus (BAV-3)
No full textThe results of a field experiment carried out in imported beef-calves to test the efficacy of intar-nasal vaccination with temperature-sensitive mutants of PI-3, IBR and BAV-3 are reported. The study was carried out on a total of 146 vaccinated and 159 control animals distributed in 3 different farms during 5 production cycles. On the basis of the observation of the occurrence of respiratory clinical signs, serological conversions, weights at slaughter, the use of the vaccine tested did not seem to have increased either the antibody levels or the resistance against respiratory diseases of vaccinated animals compared to controls. No apparent economic benefit was obtained by the use of the vaccine. Hypotheses are formulated about the possible reasons of the discrepancies between the results obtained in experiments carried out in seropositive animals under field conditions such as those of the present experiment and those obtained in seronegative animals under controlled conditions, reported by other Authors
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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