1,721,032 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Assessment of the activity of tacalcitol on psoriatic plaques by means of colorimetry and high-frequency ultrasound: A double-blind intrasubject half-side right-left comparison with betamethasone valerate and placebo
No full textThe aim of our study was to further investigate and to objectively assess the effects of tacalcitol on psoriasis by means of double-blind comparisons with placebo and betamethasone valerate, documented by instrumental evaluation. The study was conducted as intrasubject half-side right-left comparisons. Twelve subjects entered a double-blind placebo-controlled treatment (tacalcitol/placebo group), whereas 14 subjects received double-blind medication with tacalcitol/betamethasone valerate. Medications were applied once daily without occlusion to affected skin areas. Instrumental evaluations were carried out by means of a colorimeter and a 20-MHz B scanner. The colour co-ordinate a*, representing the colour range from green (-) to red (+), was used for assessing erythema. B scan images were processed according to segmentation procedures. A 0-10 interval, marking the hyporeflecting dermal areas, was used for assessing oedema and inflammatory infiltration at psoriatic plaque sites. Twenty-two patients (11 of the tacalcitol/betamethasone group and 11 of the tacalcitol/ placebo group) completed the treatment period. Mean a* values showed an increase in the tacalcitol/betamethasone group after the first week of therapy on both sides, followed by a slight decrease, the values of which did not reach statistical relevance for either treatment. The decrease observed at tacalcitol-treated sites in patients of the tacalcitol/placebo group was not significant either with respect to baseline values during the first weeks of therapy. The extension of 0-10 dermal areas decreased both in betamethasone- and tacalcitol-treated areas in both patient groups. No significant differences were noticeable between the two treatments at all assessment points, although both by clinical and echographic evaluation a more pronounced decrease in clinical scores and in echogenicity values was observable at betamethasone-valerate-treated sites, especially at weeks 6 and 8. According to our data, assessment of erythema does not always represent a valid method for monitoring the response to therapy in psoriatic patients. In fact, modifications of a* values did not allow a distinction between different treatments, whereas processing of echographic images by the 0-10 segmentation enabled tacalcitol to be classified as a topical drug, the activity of which approaches that of a potent steroid
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
MULTI-AFFINITY NANOTRAPS THAT ENHANCE DETECTION OF LOW-ABUNDANT PROTEINS: A NOVEL AND HIGHLY SENSITIVE TEST FOR THE DIAGNOSIS OF LYME DISEASE
Full text linkIn the recent years a lot of emphasis has been placed on the discovery and better detection of clinically relevant biomarkers. Biomarkers are crucial for the early detection of several diseases, and they play an important role in the improvement of current treatments, thus reducing patient mortality rate. Biofluids account for 60% of the human body mass and can be a goldmine of significant biomarkers. Unfortunately, low abundance biomarkers are difficult to detect with mass-spectrometry or immunoassays because of their low concentration in body fluids, their lability, and the presence of high-abundance proteins (i.e. albumin and immunoglobulins). In order to overcome these physiological barriers, we developed nanoparticles made of poly(N-isopropylacrylamide) (NIPAm) and functionalized with affinity reactive baits that one single step capture, concentrate and preserve labile biomarkers in complex body fluids (i.e. urine, blood, sweat, CSF). The design, synthesis and application of the Nanotrap hydrogel particles are described in this thesis. The novelty of the technology relies in the fact that in the past hydrogel nanoparticles have been studied and used as a drug delivery tool, whereas our application focuses on their capturing abilities instead of the releasing of specific drug molecules. Once the functionalized nanoparticles are incubated with a biological fluid, low molecular weight biomarkers are captured by the affinity baits while unwanted high abundance analytes are excluded. The potentially relevant biomarkers are then concentrated into small volumes and analyzed. The concentration factor (up to 10000 fold depending on the initial volume) enhances the effective sensitivity of mass-spectrometry and immunoassays and permits to detect previously invisible proteins thus improving biomarker discovery and diagnostic testing. This thesis discusses the use of hydrogel nanoparticles to develop a urinary antigen test for the detection of Lyme Borreliosis. There is a clinical need to improve the diagnostic specificity of early stage Lyme assays in the period prior to the mounting of a robust serology response and to develop a diagnostic tool to monitor therapy success. Borrelia burgdorferi is the causative agent of Lyme disease. Using our hydrogel particles (Nanotraps) we evaluated the presence of urinary Borrelia Outer surface protein A (OspA) C-terminus peptide in early stage LB before and after treatment, and in patients suspected of late stage disseminated LB. We employed Nanotraps to concentrate urinary OspA and used a highly specific anti-OspA monoclonal antibody (mAb) as a detector of the C-terminus peptides. We mapped the mAb epitope to a narrow specific OspA C-terminal domain OspA236-239 conserved across infectious Borrelia species but with no homology to human proteins and no cross reactivity with relevant viral and non-Borrelia bacterial proteins. 268 urine samples from patients being evaluated for all categories of LB were collected in a LB endemic area. The urinary OspA assay, blinded to outcome, utilized Nanotrap particle pre-processing, western blotting to evaluate the OspA molecular size, and OspA peptide competition for confirmation. OspA test characteristics: sensitivity 1.7 pg/mL (lowest limit of detection), %coefficient of variation (CV)=8%, dynamic range 1.7-30 pg/mL. Pre-treatment, 24/24 newly diagnosed patients with an erythema migrans (EM) rash were positive for urinary OspA while false positives for asymptomatic patients were 0/117 (Chi squared p<10-6). For 10 patients who exhibited persistence of the EM rash during the course of antibiotic therapy, 10/10 were positive for urinary OspA. Urinary OspA of 8/8 patients switched from detectable to undetectable following symptom resolution post-treatment. Specificity of the urinary OspA test for the clinical symptoms was 40/40. Specificity of the urinary OspA antigen test for later serology outcome was 87.5% (21 urinary OspA positive/24 serology positive, Chi squared p=4.072e-15). 41 of 100 patients under surveillance for persistent LB in an endemic area were positive for urinary OspA protein. OspA urinary shedding was strongly linked to concurrent active symptoms (e.g. EM rash and arthritis), while resolution of these symptoms after therapy correlated with urinary conversion to OspA negative. Detection of OspA was performed using Western blot analysis. In order to obtain a quantitative measurement of the antigen, an ELISA was developed. Preliminary results showed a lowest limit of detection of 0.5pg/ml and %coefficient of variation 2%, dynamic range 0.5pg-30 pg/ml. 3/3 of symptomatic patients that resulted positive with the western blot Lyme assay were also found positive when tested on ELISA. Another promising format under development uses Mass Spectrometry Multiple Reaction Monitoring (MRM) for the detection of multiple Borrelia proteins after Nanotrap processing. Developing a diagnostic test against a panel of analytes will improve clinical sensitivity and understanding of staging of disease. MRM is a prime technology that yield multiplex measurement of more than 100 peptides in a single sample. A sensitivity of 5pg/ml and high reproducibility in human urine spiked with OspA was observed. Lastly, partially degradable Nanotraps were employed to produce a prototype of Lateral Flow Immunoassay (LFI) which exploits the use of antigen displaying nanoparticles for a point of care test for Lyme disease. This technology will ensure high accuracy and sensitivity while allowing for rapid testing of Lyme disease antigens in the urine of patients in the doctor office.
In summary, this study presents data supporting the successful use of the Nanotrap technology to develop a more accurate and sensitive test for Lyme disease that can diagnose the disease before seroconversion and that can be used to monitor therapy success. Nanotraps increase the effective analytical sensitivity of western blot analysis, ELISA, mass spectrometry MRM and lateral flow immunoassay. This is a concept that can be extended to communicable diseases with different etiologic agents (e.g. Tuberculosis, Chagas disease, Toxoplasmosis, etc.)
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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