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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Comparison of the echocardiographic and electrocardiographic parameters of long term left ventricular systolic functions in patients who have VDD and DDD pacemaker implantation
No full textİstanbul Bilim Üniversitesi, Tıp Fakültesi, Kardiyoloji Anabilim DalıAmaç: VDD pacemaker sistemi, atriyoventriküler blok varlığında atriyal sensing yapıp ventrikülü uyararak atriyoventriküler senkron çalışmayı sağlayan, tek lead ve bataryadan ibaret pacemaker sistemidir. DDD pacemaker sistemi ise AV bloklu hastalardaki bu görevi çift elektrod yardımıyla yapmaktadır. Lead teknolojisinde (daha ince leadler, istenen yere fiksasyon, atriyuma direkt temas eden ikinci lead) ve batarya yazılımlarında gelişmelerle birlikte, uzun dönemde atriyal pacing ihtiyacının doğabileceği düşüncesiyle günümüzde DDD pacemaker sistemleri daha çok tercih edilmektedir. Çalışmamızda daha önce VDD pacemaker implante edilen hastaların kayıtlarından hastaların sol ventrikül fonksiyonlarının zamanla değişimini ve klinik seyrini değerlendirerek, DDD pacemaker takılan hastalarla karşılaştırmayı amaçladık.
Gereç ve Yöntem: Çalışmaya 1985-2014 yılları arasında İstanbul Bilim Üniversitesi Tıp Fakültesi Kardiyoloji Anabilim dalı poliklinik ya da acil servislerine başvuran ve çeşitli nedenlerle pacemaker implantasyonu yapılmış 2025 hastadan VDD ve DDD mod pacemaker uygulanan 1238 hasta alındı. Bu hastaların pacemaker öncesi ve uzun süreli takiplerindeki sol ventrikül sistolik fonksiyonları, komplikasyonları, takip süreleri, pacemaker implantasyon öncesi ve sonrası ritimleri, pacemaker bağımlılıkları, pacemaker ile ilgili olabilecek potansiyel sorun ve ek girişimler, kapak sorunları, koroner arter hastalığı ve revaskülarizasyon uygulanıp uygulanmadığı gibi demografik ve klinik gidişle ilgili faktörler değerlendirildi.
Bulgular: VDD ve DDD pacemaker implante edilen hastalar arasında yaş, hipertansiyon, diabetes mellitus, kalp yetersizliği ve koroner arter hastalığı açısından her ki grup arasında anlamlı farklılık yoktu (p>0.05). Ekokardiyorafik veriler karşılşatırıldığında, bazal EF, end-diastolik çap, end-sistolik çap ve ortalama sistolik pulmoner arter basıncı her iki grupta benzerdi. VDD hastalarında LA çapları DDD hastalarına göre biraz daha küçüktü (p=0.05). Hafif – orta ve ciddi olarak sınıflanan mitral yetersizliği oranları arasında her iki grup arasında istatistiksel olarak fark varken, aort yetersizliği oranları her iki grupta benzerdi. VDD hastalarında, pacemaker takılmadan önceki değerlerle karşılaştırıldığında son kontrolde ölçülen ejeksiyon fraksiyonunda anlamlı azalma (p<0.001), LV end sistolik çapı (p<0.001), LA boyutu (p<0.0001) ve sistolik PAB değerlerinde (p<0.008) anlamlı artış saptandı. Kontrol ve bazalde ölçülen LV end diastolik çapında ise anlamlı farklılık
yoktu. Yine DDD hastalarında da, takip süresince ejeksiyon fraksiyonunda anlamlı azalma, LV end diastolik çap, LV end sistolik çapı, LA boyutu ve sistolik PAB değerlerinde anlamlı artış olduğu görüldü (p<0.0001).
Sadece AV tam blok nedeniyle PM implantasyonu yapılan hastalar alınarak yapılan istatistiklerde yine her PM grubunda kontrollerindeki EF’lerde anlamlı azalma tespit edildi (p<0.0001). DDD pacemaker implante edilmiş olan hastalar RVA ve RVNA lokalizasyonlu ventriküler pacing gruplarına ayrılarak karşılaştırıldığında, RVA grubunda olanların ejeksiyon fraksiyonu RVNA grubuna göre daha yüksekti (p<0.05), RVA grubunda pacemaker takılmadan önceki değerlerle karşılaştırıldığında son kontrolde ölçülen ejeksiyon fraksiyonunda anlamlı azalma (p<0.001), RVNA grubunda, pacemaker takılmadan önceki değerlerle karşılaştırıldığında son kontrolde ölçülen ejeksiyon fraksiyonunda anlamlı azalma (p=0.022) mevcuttu.
Takip sürelerinin sonunda ulaşılabilen hastaların son kontroldeki ritmleri değerlendirildiğinde, en fazla sinüs ritminin görüldüğü grup, VDD pacemaker takılan hastalardı. Hastalarımızın uzun süreli takiplerindeki, tamponad, enfeksiyon ve pnömotoraks gibi komplikasyonlara bakıldığında her iki grup arasında fark yoktu (p>0.05). VDD PM implante edilen 7 hastaya (%1.5) takiplerinde DDD PM upgrade yapıldı. Pacemaker implantasyonu sonrası ekokardiyografi ile ölçülen EF’nin % 40 ve % 45’in altı olması ile değerlendirilen sol ventrikül sistolik disfonksiyonu oranları açısından VDD ve DDD pacemaker hastaları açısından anlamlı fark saptanmadı.
Sonuç: Hem VDD hem de DDD pacemaker takılan tüm hasta gruplarında zamanla sol ventrikül EF’de azalma ve LV çaplarında artış olmaktadır. Komplikasyon ve klinik seyir açısından VDD ve DDD modlar arasında farklılık görülmemiştir. Ancak tüm hasta grubuna bakıldığında DDD mod seçiminin avantajı olmadığı gibi, AF açısından ve batarya ömrünün kısa olması gibi dezavantajlar taşıdığı görülmektedir. AV blok olan hastalarda VDD veya DDD mod seçiminde en önemli kriter olan sinüs düğümü fonksiyonuna ek olarak hasta bazında bireysel değerlendirme yapılmalıdır.Purpose: VDD pacemaker system is composed of a battery and a lead, that stimulate the ventricle by sensing the atrium, providing synchronized activity between them in case of atrioventricular block. DDD pacemaker system, on the other hand, does this job by two leads in the AV block patients. DDD pacing has become a more preferred modality nowadays, because of the concerns about a possible need for atrial pacing in long term and developments in battery softwares and lead technology. In our study, we aimed to compare the clinical follow ups of patients who previously had a VDD pacemaker implanted to themselves with DDD patients by the clinical information and changes in left ventricular function that we obtain from previous clinical records.
Methods: Our study included 1238 VDD or DDD mode patients out of a total number of 2025 pacemaker patients, who came to emergency room or polyclinics of İstanbul Bilim University Department of Cardiology, with a diverse set of clinical situations and had their pacemaker implanted between 1985-2014. Demographic variables and data such as left ventricular systolic functions before and after pacemaker implantation, complications, pacemaker dependencies, follow up times, rhythms before and after pacemaker implantation, potential problems that may be related to pacemakers and additional interventions, valvular pathologies, coronary artery disease, whether a revascularization was performed and data about the clinical follow up were evaluated.
Results: There was no significant differences between the groups concerning age, hypertension, diabetes mellitus, heart failure and coronary artery disease (p>0,05). When echocardiographic data was compared, basal EF, end diastolic diameter, end systolic diameter and mean pulmonary artery pressure was similar in the two groups. The left atrial diameter was smaller in VDD patients compared to DDD patients (p=0,05). When mitral regurgitation was classified as mild to moderate and severe, there was a significant difference between the groups, while aortic insufficiency rates were similar. There was a significant decrease of ejection fraction (p<0,001) and increase of LV end systolic diameter (p<0,001), LA size (p<0,001) and systolic PAP (p<0,008) in VDD group. LV end diastolic diameter on the other hand, showed no significant difference when base and control measurements were investigated. Similarly in the DDD group there was a significant decrease in LV EF and increase in LV end diastolic diameter, LA size and systolic PAP levels. (p<0,0001).
When statistics were repeated including only the patients whose reason for pacemaker implantation was complete AV block, again a significant decrease in LV EF levels in both pacemaker groups (p>0,0001). When DDD group was divided into two groups according to whether the lead was implanted to RVA and RVNA, RVA group had a significantly higher EF (p0,05). DDD PM upgrades were performed to 7 patients (%1,5) who previously had a VDD PM implanted. In the comparison of the two groups when EF of 40% and 45% were taken as a cut off level for systolic dysfunction, there was no significant difference.
Conclusion: Both VDD and DDD pacemaker patients have LV EF decreases and LV diameter increases on the long term. Clinical surveys and complication frecuencies were not different in the two groups. However, it is observed that when all the patient group was taken into account, DDD mode has shown no advantages over VDD and also shown disadvantages as low battery life or when in the case of atrial fibrillation. In addition to the evaluation of sinus node function, which is the most important criterion for AV block patient in the determination of VDD or DDD, individualized evaluation should be done at patient level
Variations on the Author
Get PDF“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
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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