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Authors at the boundary: Interaction of local and general scientific literature
No full textHow a scientific literature is shaped both at the local and general level is an important question to answer. One practical way of achieving this task is to identify the roles played by authors (academicians) as actors creating and disseminating knowledge in the relevant literature. To this end, this study examines roles undertaken by authors in the field of learning organizations. Identifying role typologies first requires revealing the author citation network in the field. Citation network is a matrix that summarizes citations and citation numbers between authors. To construct this matrix, articles in the local and general literature in the field of learning organizations, published and indexed between January 01, 2015 and February 20, 2017, were collected from Google Scholar by using the Java-based Selenium Library. An author citation network with 19,525 actors was created from this list. A social network analysis was conducted to identify author roles, followed by a discussion of what these roles mean for the local literature. Despite defining four typologies, observing only one type of role typology indicates that the local literature is not well integrated with the general literature. This study recommends strategic assessments for increasing the contribution ability of local literature to general one. Using this approach, it would be possible to find answers to the questions of which roles to develop via which authors and relationships, and how to remove the obstacles to development of local literature
A New PC-Based Text Entry System Based on EOG Coding
Get PDFome disadvantages of optical eye tracking systems have increased the interest to EOG (Electrooculography) based Human Computer Interaction (HCI). However, text entry attempts using EOG have been slower than expected because the eyes should move several times for entering a character. In order to improve the writing speed and accuracy of EOG based text entry, a new method based on the coding of eye movements has been suggested in this study. In addition, a real time EOG based HCI system has developed to implement the method. In our method all characters have been encoded by single saccades in 8 directions and different dwell time. In order to standardize dwell times and facilitate the coding process, computer assisted voice guidance was used. A number of experiments have been conducted to examine the effectiveness of the proposed method and system. At the end of the fifth trials, an experienced user was able to write at average 13.2 wpm (5 letters = 1 word) with 100% accuracy using the developed system. The results of our experiments have shown that text entry with the eye can be done quickly and efficiently with the proposed method and system
Evaluation of right ventricular function in operated tetralogy of Fallot patients with tissue Doppler imaging before and after pulmonary valve replacement
No full textBackground: This study aims to investigate the efficacy of tissue Doppler echocardiography for the diagnosis of right ventricular dysfunction and for the evaluation of the response to pulmonary valve replacement.
Methods: Between December 2008 and December 2010, a total of 15 patients (8 males, 7 females; mean age: 14.5 +/- 4.5 years; range, 7 to 22 years) with pulmonary valve insufficiency in the follow-up of total correction of tetralogy of Fallot who underwent pulmonary valve replacement were included in the study. Echocardiographic imaging was performed before and one, three, and six months after replacement. Using pulse wave Doppler, early diastolic E and late diastolic A waves were measured in the flow velocity curve of tricuspid valve. Tissue Doppler measurements were made from the basal segment of right ventricular free wall and interventricular septum. S, e, and a myocardial velocities, isometric contraction time, isovolumetric relaxation time and ejection time were measured. Myocardial performance index was calculated for each patient.
Results: In pre-pulmonary valve replacement phase, s, e, a velocities and ejection time were lower in the interventricular septum compared to the basal segment of right ventricular free wall, while isometric contraction time, isovolumetric relaxation time and myocardial performance index values were higher. In the first post-replacement month, there was a significant decrease in the s value of interventricular septum, compared to pre-pulmonary valve replacement period; isometric contraction time decreased and myocardial performance index increased in the first post-pulmonary valve replacement month in the free wall of right ventricle, while isovolumetric relaxation time decreased in the postoperative third month, and s velocity, isometric contraction time and myocardial performance index increased in the postoperative sixth month. Pre-pulmonary valve replacement tissue Doppler values at the septum showed that myocardial systolic and diastolic dysfunction developed earlier than the basal segment of right ventricular free wall. This result showed that right ventricular recovery was not complete in the sixth post-pulmonary valve replacement month.
Conclusion: Tissue Doppler can show right ventricular dysfunction before replacement, but it may be insufficient to visualize right ventricular recovery until six months after treatment
Marginal Adaptation of Provisional CAD/CAM Restorations Fabricated Using Various Simulated Digital Cement Space Settings
No full textPurpose: The ideal digital cement space value for the fabrication of provisional computer-aided design/ computer-aided manufacturing (CAD/CAM) crowns with clinically acceptable marginal adaptation is not well known. The aim of this study was to evaluate the effect of different simulated cement space settings on the marginal tit of poly(methyl methacrylate) (PMMA) provisional CAD/CAM restorations. Materials and Methods: An extracted premolar tooth was prepared using ceramic crown preparation guidelines and represented both natural teeth and/or custom implant abutments. The prepared tooth abutment was scanned with a three-dimensional (3D) laboratory scanner (D900, 3Shape). CAD design software was used to subsequently design a premolar crown core with three different simulated cement space settings (20 to 40 mu m, 20 to 50 mu m, 20 to 60 mu m). PMMA blocks were used to mill the specimens (n = 9, N = 27). Using a stereo zoom microscope, a total of 36 images for each of the 3 groups (9 crowns per group, 4 sites per crown) were captured to measure the mean vertical marginal discrepancy for every group. One-way analysis of variance (ANOVA) was used to analyze the data, and the post hoc Tukey multiple comparison test was performed. Results: The marginal gap values of the PMMA cores fabricated using the three cement space settings were significantly different from each other (P < .001). The marginal gap was smaller with a 20- to 60-mu m setting compared with 20 to 50 mu m and 20 to 40 mu m, and the 20- to 50-mu m setting allowed for smaller marginal gaps compared with 20 to 40 mu m (P < .001). Conclusion: Within the limitations of this study, the marginal gaps of CAD/CAM-fabricated PMMA cores were smaller when the cement space was larger. The smallest marginal gaps were achieved when a 20- to 60-mu m cement space was used (P < .001)
Turkish neonatal society guideline on the neonatal pain and its management
No full textPain control is an important ethical issue to be considered and constitutes the basis of treatment in premature and term newborns. The inadequacy of pain control in these infants in neonatal intensive care units leads to neurodevelopmental and behavioral problems in the long term. For this reason, it is extremely important to raise awareness of the presence of pain in newborn infants, to reduce invasive procedures applied to infants as much as possible, and to minimize pain with non-pharmacologic or pharmacologic treatments when it is inevitable. © Copyright 2018 by Turkish Pediatric Association
Both Granulocytic and Non-Granulocytic Blood Cells Are Affected in Patients with Severe Congenital Neutropenia and Their Non-Neutropenic Family Members: An Evaluation of Morphology, Function, and Cell Death
No full textObjective: To examine granulocytic and non-granulocytic cells in children with severe congenital neutropenia (SCN) and their non-neutropenic parents.
Materials and Methods: Fifteen patients with SCN and 21 non-neutropenic parents were evaluated for a) CD95, CD95 ligand, annexin V, propidium iodide, cell cycle, and lymphocyte subsets by flow cytometry; b) rapid cell senescence (of leukocytes) by senescence-associated beta-galactosidase stain; c) aggregation tests by aggregometer; d) in vitro bleeding time by PFA-100 instrument; e) mepacrine-labeled dense granule number of thrombocytes by fluorescence microscope; and f) hematomorphology by light and electron microscope. HAX1, ELANE, G6PC3, CSF3R, and JAGN1 mutations associated with SCN were studied in patients and several parents.
Results: Significant increase in apoptosis and secondary necrosis in monocytes, lymphocytes, and granulocytes of the patients and parents was detected, irrespective of the mutation type. CD95 and CD95 ligand results implied that apoptosis was non-CD95-mediated. Leukocytes of 25%, 12.5%, and 0% of patients, parents, and controls showed rapid cell senescence. The cell cycle analysis testable in four cases showed G1 arrest and apoptosis in lymphocytes of three. The patients had HAX1 (n=6), ELANE (n=2), G6PC3 (n=2), and unidentified (n=5) mutations. The CD3, CD4, and NK lymphocytes were below normal levels in 16.6%, 8.3%, and 36.4% of the patients and in 0%, 0%, and 15.4% of the parents (controls: 0%, 0%, 5.6%). The thrombocytes aggregated at low rates, dense granule number/thrombocyte ratio was low, and in vitro bleeding time was prolonged in 37.5%-66.6% of patients and 33.3%-63.2% of parents (vs. 0% in controls). Under electron and/or light microscope, the neutrophils, monocytes, lymphocytes, and thrombocytes in the peripheral blood of both patients and parents were dysplastic and the bone marrow of patients revealed increased phagocytic activity, dysmegakaryopoiesis, and necrotic and apoptotic cells. Ultrastructurally, thrombocyte adhesion, aggregation, and release were inadequate.
Conclusion: In cases of SCN, patients' pluripotent hematopoietic stem cells and their non-neutropenic parents are both affected irrespective of the genetic defect
Retrospective Evaluation of Patients who Underwent Laparoscopic Bariatric Surgery
No full textObjective: In the present study, we aimed to retrospectively evaluate the preoperative characteristics, intraoperative and postoperative results of patients who underwent laparoscopic obesity surgeries.
Methods: After obtaining the approval of the Ethics Committee, records of patients who underwent laparoscopic obesity surgery from January 2013 to December 2016 were reviewed. Demographic characteristics, medications used in anaesthesia and analgesia, the duration of recovery unit/hospital stay, intensive care unit/mechanical ventilation requirements and complications were recorded.
Results: A total of 329 ASA II-III patients over a 3-year period were operated. Thiopental and propofol were administered at induction, sevoflurane, isoflurane and desflurane were administered for the maintenance, and vecuronium and rocuronium were administered to aid in neuromuscular blockage. The mean durations of recovery unit and hospital stays were 30.80 +/- 6.01 minutes and 4.27 +/- 1.68 days, respectively. The hypnotic agent, muscle relaxant or inhalation anaesthetics used did not have a significant effect on the duration of recovery unit and hospital stay. Mask ventilation and intubation were noted to be difficult in 5.5% and 8.5% of the cases, respectively. The presence of obstructive sleep apnoea syndrome and high body mass index and Mallampati scores significantly increased difficult mask ventilation and difficult intubation rates. Four patients were transferred to intensive care unit for close monitoring. Two patients were re-operated on, two patients had rhabdomyolysis, one patient had Wernicke's encephalopathy and two patients had peripheral neuropathy. Perioperative mortality did not occur in any patient.
Conclusion: We believe that appropriate patient selection, the use of well-designed anaesthesia and surgical protocols play important roles in increasing the success rate of patient outcomes and early and late complications in laparoscopic obesity surgery
On reflexivity of the Bochner space L-P (mu, E) for arbitrary mu
No full textLet (Omega, A, mu) be a finite positive measure space, E a Banach space, and 1 < p < infinity. It is known that the Bochner space L-P (mu, E) is reflexive if and only if E is reflexive. It is also known that L(L-1(mu), E) = L-infinity (mu, E) if and only if E has the Radon-Nikodym property. In this study, as an application of hyperstonean spaces, these results are extended to arbitrary measures by replacing the given measure space by an equivalent perfect one
Clinical practices of the management of nonvalvular atrial fibrillation and outcome of treatment: A representative prospective survey in tertiary healthcare centers across Turkey
No full textObjective: The goal of this study was to define clinical practice patterns for assessing stroke and bleeding risks and thromboprophylaxis in nonvalvular atrial fibrillation (NVAF) and to evaluate treatment outcomes and patient quality of life.
Methods: A clinical surveillance study was conducted in 10 tertiary healthcare centers across Turkey. Therapeutic approaches and persistence with initial treatment were recorded at baseline, the 6th month, and the 12th month in NVAF patients.
Results: Of 210 patients (57.1% male; mean age: 64.86 +/- 12.87 years), follow-up data were collected for 146 patients through phone interviews at the 6th month and 140 patients at the 12th month. At baseline, most patients had high CHADS(2) score (>= 2: 48.3%) and CHA(2)DS(2)-VASc (>= 2: 78.7%) risk scores but a low HAS-BLED (0-2: 83.1%) score. Approximately two-thirds of the patients surveyed were using oral anticoagulants as an antithrombotic and one-third were using antiplatelet agents. The rate of persistence with initial treatment was approximately 86%. Bleeding was reported by 22.6% and 25.0% of patients at the 6th and 12th month, respectively. The proportion of patients with an INR of 2.0-3.0 was 41.8% at baseline, 65.7% at the 6th month, and 65.9% at the 12th month. The time in therapeutic range was 61.0% during 1 year of follow-up. The median EuroQol 5-dimensional health questionnaire (EQ-5D) score of the patients at baseline and the 12th month was 0.827 and 0.778, respectively (p<0.001). The results indicated that patient quality of life declined over time.
Conclusion: In atrial fibrillation, despite a high rate of persistence with initial treatment, the outcomes of stroke prevention and patient quality of life are not at the desired level. National health policies should be developed and implemented to better integrate international guidelines for the management of NVAF into clinical practice
Evaluation of Different Restoration Combinations Used in the Reattachment of Fractured Teeth: A Finite Element Analysis
No full textObjective. The purpose of this study was to test different restoration combinations used for constructing fractured endodontically treated incisors by reattaching their fractured fragments. Methods. Seven types of 3-D FEM mathematical root canal-filled models were generated, simulating cases of (OB) reattaching fractured fragments; (CrPL) reattaching fractured fragments + ceramic palatinal laminate; (CmPL) reattaching fractured fragments + composite palatinal laminate; (CM) reattaching fractured fragments + coronal 1/3 of the root was filled using core material; (BP) reattaching fractured fragments + glass fiber post; (CP) composite resin restoration + glass fiber post; and (OC) composite resin restoration. A 100-N static oblique force was applied to the simulated teeth with 135 degrees on the node at 2 mm above the cingulum to analyze the stress distribution at the tooth. Results. For enamel tissue, the highest stress values were observed in model BP, and the lowest stress values were observed in model CmPL. For dentine tissue, the highest stress concentrations were observed around the fracture line for all models. Conclusions. Reattachment of fractured fragments by bonding may be preferred as a restoration option for endodontically treated incisors; also, palatinal laminate decreases the stress values at tooth tissues, especially at the enamel and the fracture line