1,721,082 research outputs found
Fathi Ali Adow
No full textThis is a research on gender and diplomacy in Africa with a focus on Somalia. Somalia createdthe ministry of foreign affairs in 1963 with the responsibility to recruit competent men andwomen to implement Somalia’s foreign policy goals. However, the gender gap in Somalia’s Foreign Service is glaring especially in top ranking positions
Estrogen induces nitric oxide production via nitric oxide synthase activation in endothelial cells.
No full textINTRODUCTION
17β-estradiol (E2) has been found to induce vasodilation in the cardiovascular system and at physiological levels, resulting in prevention of cerebral vasospasm following subarachnoid hemorrhage (SAH) in animal models. The goal of this study was to analyze the cellular mechanism of nitric oxide (NO) production and its relation to E2, in vitro in brain and peripheral endothelial cells.
METHODS
Human umbilical endothelial cells (HUVEC) and brain endothelial cells (bEnd.3) were treated with estradiol (E2, 0.1, 10, 100, and 1,000 nM), and supernatant was collected at 0, 5, 15, 30, 60, and 120 min for nitric oxide metabolome (nitrite, NO₂) measurements. Cells were also treated with E2 in the presence of 1400W, a potent eNOS inhibitor, and ICI, an antagonist of estradiol receptors (ERs). Effects of E2 on eNOS protein expression were assessed with Western blot analysis.
RESULTS
E2 significantly increased NO2 levels irrespective of its concentration in both cell lines by 35 % and 42 % (p 0.05). The combination of E2 (10 nM) and a NOS inhibitor (1400W, 5 μM) inhibited NO2 increases in addition (4 %, p > 0.05). E2 induced increases in eNOS protein levels and phosphorylated eNOS (eNOS(p)).
CONCLUSIONS
This study indicates that E2 induces NO level increases in cerebral and peripheral endothelial cells in vitro via eNOS activation and through E2 receptor-mediated mechanisms. Further in vivo studies are warranted to evaluate the therapeutic value of estrogen for the treatment of SAH-induced vasospasm
Blood Clot Placement Model of Subarachnoid Hemorrhage in Non-human Primates
No full textDespite ongoing extensive and promising research to prevent and treat cerebrovascular vasospasm and delayed ischemic neurological deficits (DIND) after aneurysmal subarachnoid hemorrhage (aSAH), clinical outcomes remain unsatisfying. Neuroprotective strategies developed in basic science research laboratories need to be translated from bench-to-bedside using appropriate animal models. While a primate model is widely accepted as the best animal model mimicking development of delayed cerebral vasospasm after aSAH, its worldwide usage has dramatically decreased because of ethical and financial limitations. However, the use of primate models of subarachnoid hemorrhage (SAH) remains a recommended bridge for translation of early preclinical studies in rodents to human clinical trials. This paper discusses the technical aspects as well as advantages and disadvantages of a blood clot placement model of subarachnoid hemorrhage in non-human primates.
Keyword
Development and evaluation of an improved multiple frequency bioimpedance analyzer for disease management system / Sami Fathi Ali Khalil
Get PDFThis thesis presents the development of a novel multiple frequency bioimpedance analyzers (MFBIA). The analyzer is designed for diseases management, focusing on the management of dengue infection and the monitoring of high cholesterol level. The developed system consists of the hardware and the software modules. The advanced hardware (assembled in 8x4.5x2 cm box) measures the impedance parameters at 5 KHz, 50 KHz, 100 KHz and 200 KHz at the accuracy of 3.6 %, with an output current of 0.2 mA. The body composition prediction module was modeled from predefined equations using the data from 825 healthy Malaysian subjects. The diseases management system was developed based on the Bioimpedance Vector Analysis (BIVA) technique using data from 299 dengue patients and 339 high cholesterol elderly patients. The obtained results from the electrical testing showed maximum error at only 3.6% from the theoretical values. The validation using biological phantom presented significant correlations in estimating fat and fluid volumes using the developed MFBIA analyzer. The analysis of the equations showed that the Deurenberg’s model are the most appropriate method for the estimation of Fat-Free Mass, Fat Mass, Total Body Water, Extracellular Fluid and Intracellular Fluid as referenced to Dual Energy X-ray Absorptiometry. The investigation on the healthy subjects indicates significant correlation (Pearson’s correlation ≥ 0.8) between commercial analyzers and the developed MFBIA analyzer. The results from the BIVA analysis disclosed a significant vector shifting between the healthy and Dengue infected subjects (P<0.05) and the means impedance vector of normal and high cholesterol groups do differ significantly (P<0.05). In conclusion, a new MFBIA was designed and developed, and a novel diseases management system for dengue infection, and cholesterol level introduced
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
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
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