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Browsing by Publisher "SAGE Publications Ltd"

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A large family with type IV radial polydactyly
(SAGE Publications Ltd, 1998) Seyhan A.; Akarsu N.; Keskin F.
This study examines one of the largest pedigrees with radial polydactyly type IV (uncomplicated polysyndactyly) comprising a total of 69 individuals, of whom 26 have been affected over six generations. Typical manifestations of the pedigree were bilateral radial and ulnar digital duplications, as well as syndactyly between the middle and ring fingers and the second and third toes. There was no craniofacial anomaly in any of the 17 cases examined physically. This observation suggests that radial polydactyly type IV and Greig craniofacial-synostosis syndrome with similar digital manifestations are clinically-distinct entities. © 1998 The British Society for Surgery of the Hand.
Effect of material nonlinearity on symmetric aluminum metal-matrix laminated composite beams under a bending moment
(SAGE Publications Ltd, 2004) Sayman O.; Čllioģlu H.; Meriç C.; Can N.
In this study, an elastic-plastic stress analysis is carried out on symmetric laminated composite beams subjected to a bending moment. The composite beam is to be strain hardening. The Tsai-Hill theory is used as a yield criterion in the solution. The Bernoulli and Euler hypotheses are assumed to be valid. The beam lay-up sequences are chosen as [90°/0°]s, [30°/-30°]s,[45°/-45°] s, and [60°/-60°]s. The bending moment starting plastic yielding is found to be highest for [30°/-30°]s orientation. αx residual stress component is found to be highest at the upper and lower surfaces. However σx residual stress component becomes the highest at the elastic and plastic boundary for further expansion of the plastic region. The transverse displacement is obtained at the free end, numerically.
Comparative morphometry of the lower lumbar vertebrae: Osteometry in dry bones and computed tomography images of patients wtih and without low back pain
(SAGE Publications Ltd, 2006) Varol T.; Iyem C.; Cezayirli E.; Erturk M.; Kayalioglu G.; Hayretdag C.
Various factors affect the development of the vertebral canal. The dimensions of the vertebral canal and the intervertebral foramen can be altered by these factors before or after birth. Sex differences in dimensions have also been reported. When there is a stenosis of the vertebral canal or the intervertebral foramen, neural structures confined within them can be affected easily, resulting in symptoms. Using computed tomography images, we compared vertebral canal dimensions in 100 patients with low back pain and/or radiculopathy with those in 40 healthy, non-symptomatic controls. We also measured the dimensions of 275 dry bones. We found significant correlations among the variables in the live subjects. We found significant differences between patients and controls in the variables that were measured. Stenoses were more prevalent in females. Dry bone measurements showed some sex differences, and stenosis mainly in vertebrae L4, L5 and S1. Copyright © 2006 Cambridge Medical Publications.
Weldability of AL99-SiC Composites by CO2 laser welding
(SAGE Publications Ltd, 2009) Durmus H.; Meric C.
In this study, Al99ĝ€"SiC composites were produced using PM method. In the composites produced, the reinforcement rates of SiC were 0, 5, 10, and 20 (%wt). The matrix Al 99 powders were mechanically mixed with SiC particulates. These powders were compacted at room temperature at 500 MPa for 5 - 10 - 60 mm specimens and followed by sintering at 600 and 620°C for 1 h. Composite specimens were joined by CO2 laser welding method. Rofinĝ€"Sinar SM2000 machine was used for the welding process. The microstructure of melted region was investigated by optical, scanning, and X-ray microchemical analysis techniques. The hardness test, tensile test, and three-point bend test results were presented. The effect to CO2 laser welding method at different reinforcement rates and different sintering temperatures in Al 99 powder was investigated. Because of the lower thermal conductivity of Al99ĝ€"SiC composites, melting zone is wide. It was observed that 0.5 m/min laser welding velocity was suitable for composites with low SiC rate (0% and 5% SiC), and with increasing SiC (10 and 20%), laser welding velocity of 0.3 m/min was suitable. © SAGE Publications 2009.
Apoptosis-mediated cytotoxic effects of ibandronic acid on hormone-and drug-refractory prostate cancer cells and human breast cancer cells
(SAGE Publications Ltd, 2010) Kucukzeybek Y.; Gorumlu G.; Cengiz E.; Karabulut B.; Sezgin C.; Atmaca H.; Sanli U.A.; Uzunoglu S.; Uslu R.
Over 80% of patients with advanced breast and prostate cancer ultimately develop bone metastases. Ibandronic acid has proven efficacy for treatment of bone metastasis secondary to breast cancer. This study was designed to investigate the cytotoxic and apoptotic effects of ibandronic acid on hormone- and drug refractory prostate carcinoma DU-145 and human breast cancer MCF-7 cell lines. Cytotoxicity was evaluated using an XTT cell proliferation kit, and apoptosis was assessed by enzyme-linked immuno sorbent assay (histone-DNA fragmentation) and measurement of caspase 3/7 activity. With increasing concentrations of ibandronic acid there was a dose- and time-dependent decrease in cell numbers. MCF-7 cells were more resistant than DU-145 cells (half maximal inhibitory concentrations of 122 and 90 μM, respectively). Ibandronic acid induced apoptosis in both cell lines. The study showed an apoptosis-mediated cytotoxic effect for ibandronic acid (in addition to the already known osteoclast inhibiting effect) in breast cancer patients with bone metastases; which was also observed in prostate cancer cells. Further clinical studies involving breast and prostate cancer patients with bone metastases are warranted to confirm these findings. © 2010 Field House Publishing LLP.
Medial patellofemoral ligament reconstruction in skeletally immature patients
(SAGE Publications Ltd, 2014) Yercan H.S.; Kale G.; Erkan S.; Özalp T.; Okcu G.
Objectives: To evaluate the clinical outcome after medial patellofemoral ligament (MPFL) reconstruction for patellofemoral instability in skeletally immature patients. Methods: Study participants were 8 patients (median age, 10 years; range, 5-14 and one male, others female) who had suffered from persistent patellofemoral instability. Our technique preserves femoral and patellar insertion anatomy of MPFL using a free semitendinosus autograft, together with tenodesis to the adductor magnus tendon thus sparing the open physis of distal femur and the patellar attachment of MPFL. The clinical results were evaluated preoperatively and the final follow-up period using the Kujala patellofemoral score. Patellar shift, tilt and height were measured preoperatively and on the latest follow-up on plain radiographs. Results: At average 42 months follow-up (range, 16 to 56), %80 of patients were satisfied with the treatment. Redislocation or instability symptoms occurred in two patients. No apprehension signs or redislocations were seen in the remanining six patients. A significant improvement (p<0.05) in Kujala score (from 36 to 77) was found. Patellar shift & tilt decreased to anatomic values in six patients but patella alta persisted. Conclusion: The result of this study show that MPFL reconstruction with our technique seems to be an effective treatment for recurrent and habitual patellofemoral dislocation in skeletally immature patients; leading to significant increases in stability and functionality. © The Author(s) 2014.
Comparison of ankle proprioception between blind and healthy athletes
(SAGE Publications Ltd, 2014) Özer M.; Kaynak H.; Atik A.; Şilil M.K.; Altun M.; Akseki D.
Objectives: The positive effect of the visual sensation on the proprioceptive quality is well known. Although other senses of the congenital blind individuals have been proven to be increased more than healthy ones, there has been no data about the proprioceptive quality of congenital blind persons. The aim of this study is to determine the quality of ankle proprioception in congenital blind athletes. Methods: 15 congenital blind athletes (10 males and 5 females) with a mean age of 24 ± 2.9 (ranging from 20 to 29), and 15 healthy athletes (10 males and 5 females) with a mean age of 24.6 ± 3.05 (ranging from 20 to 29), from the same athletic department, were included in the study. Proprioception was evaluated by using the technique of joint position sense, and absolut errors during the reproduction of six target angles (plantar flexion 100, dorsiflexion 50, inversion 100 and 200, eversion 100 and 200) were detected in dominant and nondominant ankles of both groups. Athletes were measured both eyes open and closed. Statistical analysis was done by using Mann-Whitney U and Wilcoxon Signed Ranks tests. Results: When dominant extremities were compared while eyes open, there was only a difference in 50 dorsiflexion measurements statistically in favor of blind ones (p<0.05). When dominant extremities were compared while eyes closed, blind athletes got less wrong in four of the six target angles statistically (p<0.01), when non-dominant extremities were compared while eyes closed, blind athletes got less wrong in all angles statistically (p<0.01). The ankle proprioception of the blind athletes were better then the normal athletes. The ankle propriceptions of the normal athletes further deteriorated when their eyes were closed. Conclusion: We found that the ankle proprioceptions of congenital blind athletes were better than the normal athletes. So additional closed-eyes exercises can help to reach a high proprioceptive level of athletes in a normal season which in terms may decrease accidental traumas. © The Author(s) 2014.
Influence of pectoralis minor muscle and upper trapez muscle tightness in scapular dyskinesis
(SAGE Publications Ltd, 2014) Yeşilyaprak S.S.; Yüksel E.; Kalkan S.
Objectives: Alterations in scapular kinematics were found in individuals with shoulder problems compared with healthy individuals. These alterations in scapular kinematics such as changes in the normal position or any abnormal motion of the scapula during active motions are defined as "Scapular Dyskinesis (SD)". Relationship between tight muscles and scapular kinematics has been investigated. Pectoralis Minor Muscle Tightness (PMMT) effects scapular motion and make changes in scapular kinematics. Although there are some studies indicating a possible relationship between PMM or Upper Trapezius Muscle Tightness (UTMT) and SD, this relationship hasn’t been investigated yet. The aim of this study was to evaluate the influence of PMMT and UTMT on SD in an asymptomatic population. Methods: One-hundred-eleven participants (mean age: 22.73±3.45 years old, 222 arms, 42 Female-69 Male) were recruited. Subjects were eligible if they were ≥18 years of age, having active full shoulder motion and who has no health problem to hinder them from participate. Individuals with symptoms produced by cervical spine motion, impingement syndrome, frozen shoulder, shoulder instability and a history of shoulder fracture/surgery were excluded. Scapular Dyskinesis Test (SDT) was used to identify SD. PMMT was determined by Pectoralis Minor Index (PMI), UTMT by UTMT Test. Logistic regression analysis performed to ascertain the effects of PMMT and UTMT on the likelihood that participants have SD. Results: SD was identified in 62 arms (27.9%), PMMT in 32 arms (14.4%), and UTMT in 75 arms (33.8%) in total number of participants. PMMT was determined in 23 arms (37.1%) and UTMT in 39 arms (62.9%) in participants with SD. The logistic regression model was statistically significant, X2=65.472, p<.000, df= 2. The model explained 36.8% (Nagelkerke R2) of the variance in SD and correctly classified 78.4% of cases. The Wald criterion demonstrated that both PMMT and UTMT made a significant contribution to prediction (p<0.000 for PMMT, p<0.000 for PMMT). People who have PMMT were 13.76 times more likely to exhibit SD than people who haven’t. People who have UTMT were 7.59 times more likely to exhibit SD than people who haven’t. Conclusion: It was determined that people with PMMT and UTMT are more likely to exhibit SD than people who have normal muscle length in this asymptomatic population. Assessment of PMMT and UTMT could be included as a routine part of the scapula and scapular dyskinesia examination. This investigation should be repeated in symptomatic population who has shoulder problems. The effects of various interventions for lengthening these muscles in scapular dyskinesia, needs further research. © The Author(s) 2014.
Subclinical hypothyroidism: Comparison of adhesion molecule levels before and after levothyroxine therapy
(SAGE Publications Ltd, 2014) Bilgir F.; Bilgir O.; Calan M.; Calan O.; Isikyakar T.
Objective: Adhesion molecules are involved in inflammation, atherosclerosis and malignancy. This study measured levels of adhesion molecules before and after levothyroxine therapy in patients with subclinical hypothyroidism (SHO). Methods: Levels of soluble (s) intracellular adhesion molecule (ICAM)-1, s vascular cell adhesion molecule (sVCAM) VCAM-1 and sE-selectin were analysed in patients diagnosed with SHO, prior to administration of 50 mg/day levothyroxine orally for 3 months. Subsequently, levels of sICAM-1, sVCAM-1 and sE-selectin were reanalysed then compared with the pretreatment levels. Results: In 30 patients with SHO, levels of sICAM-1 were found to be significantly higher than those in healthy controls, (P=0.001). Post-treatment sICAM-1 levels were significantly lower than pretreatment levels (P=0.001). No significant differences were found in sVCAM-1 or sE-selectin levels between healthy controls and patients with SHO before treatment, or between patients with SHO pre- and post-treatment. Conclusions: Patients with SHO had significantly higher levels of sICAM-1 compared with controls. Levels became normal after treatment with levothyroxine. These findings emphasize the need for levothyroxine therapy in cases of SHO to normalize sICAM-1 levels. Such treatment helps to prevent the future development of atherosclerosis or cancer. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Effects of axial impacts at different temperatures on failure response of adhesively bonded woven fabric glass fiber/epoxy composite joints
(SAGE Publications Ltd, 2015) Sayman O.; Soykok I.F.; Dogan T.; Dogan A.; Arikan V.
Evaluating post-impact failure responses of single-lap adhesively bonded composite-to-composite joints in uniaxial static tensile loading was the main objective of the current experimental study. At first, axial tensile impacts having various energy levels (10, 15, 20, and 25 J) were applied to the joints at different temperatures (-20, 0, room temperature, 50, and 80). Afterward, the samples were secondarily subjected to static tensile loading at ambient temperature, so that reductions in joint strengths arising from the impacts performed under different loading conditions could be assessed. Consequently, it was definitely proved that each of the axial impacts performed in any loading case has a noticeable effect on ultimate joint strengths, proportionally to the acting condition. Besides, the combination of high energy and temperature sometimes appeared to be the reason of impact failure, which occurs instantly without being able to perform axial static tests. When applied energy and/or absolute difference from room temperature is increased, lower joint resistances could be measured during secondary tensile tests. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Usage of whey protein may cause liver damage via inflammatory and apoptotic responses
(SAGE Publications Ltd, 2015) Gürgen S.G.; Yücel A.T.; Karakuş A.; Çeçen D.; Özen G.; Koçtürk S.
The purpose of this study was to investigate the long- and short-term inflammatory and apoptotic effects of whey protein on the livers of non-exercising rats. Thirty rats were divided into three groups namely (1) control group, (2) short-term whey (WS) protein diet (252 g/kg for 5 days), and (3) long-term whey (WL) protein diet (252 g/kg for 4 weeks). Interleukin 1β (IL-1β), IL-6, tumor necrosis factor α (TNF-α), and cytokeratin 18 (CK-18-M30) were assessed using enzyme-linked immunosorbent assay and immunohistochemical methods. Apoptosis was evaluated using the terminal transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) method. Hepatotoxicity was evaluated by quanitation of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Based on the biochemical levels and immunohistochemical results, the highest level of IL-1β was identified in the WL group (p < 0.01). The IL-6 and TNF-α results were slightly lower in the WS group than in the control group and were highest in the WL group (p < 0.01). The CK-18-M30 and TUNEL results were highest in the WS group and exhibited medium intensity in the WL group (p < 0.01). AST results were statistically significant for all groups, while our ALT groups were particularly significant between the WL and control groups (p < 0.01). The results showed that when whey protein is used in an uninformed manner and without exercising, adverse effects on the liver may occur by increasing the apoptotic signal in the short term and increasing inflammatory markers and hepatotoxicity in the long term. © The Author(s) 2014.
Assessment of serum chemerin, vaspin and omentin-1 levels in patients with polycystic ovary syndrome
(SAGE Publications Ltd, 2016) Guvenc Y.; Var A.; Goker A.; Kuscu N.K.
Objective: To determine serum chemerin, vaspin and omentin-1 in overweight and normal weight patients with polycystic ovary syndrome (PCOS) and investigate the possible relationship between these adipokines and metabolic syndrome. Methods: This cross sectional study enrolled women with PCOS and healthy women. Serum chemerin, vaspin and omentin-1 were assessed by enzyme-linked immunosorbent assay methods. Results: Forty patients with PCOS and 30 healthy controls were included in the study. In the PCOS group, 18 women were overweight (body mass index [BMI] = 25.0–29.9 kg/m2) and 22 had normal weight (BMI = 18.5–24.9 kg/m2). Chemerin, total cholesterol, dehydroepiandrosterone sulphate and free androgen index (FAI) were significantly higher; and high-density lipoprotein cholesterol and sex hormone binding globulin were significantly lower in overweight PCOS patients compared with normal weight PCOS patients. A positive correlation was found between chemerin and BMI, triglyceride, insulin, homeostatic model assessment of insulin resistance and FAI in the PCOS group. There was no difference in serum chemerin, vaspin and omentin-1 between PCOS patients and healthy controls. Conclusion: Circulating chemerin was increased in overweight compared with normal weight PCOS patients. The most predictive variables for circulating chemerin in PCOS patients were BMI, FAI and age. © 2016, © The Author(s) 2016.
Dynamic behavior predictions of fiber-metal laminate/aluminum foam sandwiches under various explosive weights
(SAGE Publications Ltd, 2016) Baştürk S.B.; Tanoğlu M.; Çankaya M.A.; Eğilmez O.Ö.
Application of blast tests causes some problems to characterize the performance of panels due to the drastic conditions of explosive medium. Real test has high safety concerns and is not easily accessible because of its extra budget. Some approaches are needed for the preliminary predictions of dynamic characteristics of panels under blast loading conditions. In this study, the response of sandwiches under blast effect was evaluated by combining quasi-static experiments and computational blast test data. The primary aim is to relate the quasi-static panel analysis to dynamic blast load. Based on this idea, lightweight sandwich composites were subjected to quasi-static compression loading with a special test apparatus and the samples were assumed as single degree-of-freedom mass-spring systems to include dynamic effect. This approach provides a simpler way to simulate the blast loading over the surface of the panels and reveals the possible failure mechanisms without applying any explosives. Therefore the design of the panels can be revised by considering quasi-static test results. In this work, the peak deflections and survivabilities of sandwiches for various explosive weights were predicted based on the formulations reported in the literature. Major failure types were also identified and evaluated with respect to their thicknesses. © The Author(s) 2015.
Classifier and feature set ensembles for web page classification
(SAGE Publications Ltd, 2016) Onan A.
Web page classification is an important research direction on web mining. The abundant amount of data available on the web makes it essential to develop efficient and robust models for web mining tasks. Web page classification is the process of assigning a web page to a particular predefined category based on labelled data. It serves for several other web mining tasks, such as focused web crawling, web link analysis and contextual advertising. Machine learning and data mining methods have been successfully applied for several web mining tasks, including web page classification. Multiple classifier systems are a promising research direction in machine learning, which aims to combine several classifiers by differentiating base classifiers and/or dataset distributions so that more robust classification models can be built. This paper presents a comparative analysis of four different feature selections (correlation, consistency, information gain and chi-square-based feature selection) and four different ensemble learning methods (Boosting, Bagging, Dagging and Random Subspace) based on four different base learners (naive Bayes, K-nearest neighbour algorithm, C4.5 algorithm and FURIA algorithm). The article examines the predictive performance of ensemble methods for web page classification. The experimental results indicate that feature selection and ensemble learning can enhance the predictive performance of classifiers in web page classification. For the DMOZ-50 dataset, the highest average predictive performance (88.1%) is obtained with the combination of consistency-based feature selection with AdaBoost and naive Bayes algorithms, which is a promising result for web page classification. Experimental results indicate that Bagging and Random Subspace ensemble methods and correlation-based and consistency-based feature selection methods obtain better results in terms of accuracy rates. © Chartered Institute of Library and Information Professionals.
Evaluation of linden fibre as a potential reinforcement material for polymer composites
(SAGE Publications Ltd, 2016) Seki Y.; Seki Y.; Sarikanat M.; Sever K.; Durmuşkahya C.; Bozacı E.
The aim of this study is to characterize linden fibres as a novel cellulose-based fibre to be used as a reinforcement material in composites and to investigate the adhesion property to unsaturated polyester. Up to now, there is no report regarding the potential usability of linden fibre in composite applications. Linden fibres were extracted from the stem of a plant of Tilia rubra DC. subsp. caucasica (Rupr.) V.Engl. Characterization of linden fibres was studied by Fourier transform infrared, X-ray photoelectron spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, tensile and pull-out tests. Morphological properties of the fibres were observed through scanning electron and optical microscopes. Initial degradation temperature of the linden fibre was reported to be 238℃. The tensile strength and the Young’s modulus of the linden fibres were calculated to be 675.4 ± 45.7 MPa and 61.0 ± 9.8 GPa, respectively. The interfacial shear strength of the linden fibre with unsaturated polyester matrix was computed as 26.15 ± 2.27 MPa via pullout test. This study offers an alternative and eco-friendly reinforcement material which may have usability potential in polymeric composites. © 2014, © The Author(s) 2014.
An accurate toponym-matching measure based on approximate string matching
(SAGE Publications Ltd, 2016) Klllnç D.
Approximate string matching (ASM) is a challenging problem, which aims to match different string expressions representing the same object. In this paper, detailed experimental studies were conducted on the subject of toponym matching, which is a new domain where ASM can be performed, and the creation of a single string-matching measure that can perform toponym matching process regardless of the language was attempted. For this purpose, an ASM measure called DAS, which comprises name similarity, word similarity and sentence similarity phases, was created. Considering the experimental results, the retrieval performance and system accuracy of DAS were much better than those of other well-known five measures that were compared on toponym test datasets. In addition, DAS had the best metric values of mean average precision in six languages, and precision/recall graphs confirm this result. © Chartered Institute of Library and Information Professionals.
Fabrication and characterization of poly(ε-caprolactone) coated silicate and borate-based bioactive glass composite scaffolds
(SAGE Publications Ltd, 2016) Deliormanli A.M.
In this study, silicate 13-93 and borate based 13-93B3 bioactive glass scaffolds with high porosity and interconnected pore structure (pore size 100-500 μm) were prepared by foam replication method. In order to improve the mechanical properties, the scaffolds were coated and infiltrated with a poly(ε-caprolactone) (PCL) solution at different concentrations (5, 10, and 20 wt%). Results revealed that the mechanical properties of the scaffolds were significantly improved by the PCL coating. The addition of 10% PCL coating led to approximately 10-fold increase of compressive strength in comparison with noncoated scaffolds. The bioactivity of scaffolds upon immersion in simulated body fluid was maintained in the PCL-coated scaffolds at all concentrations; however, a decrease in the formation rate and amount of crystalline hydroxyapatite was observed as the PCL concentration was increased in the coating layer. Degradation rate of the borate-based bioactive glass scaffolds was tailored by the PCL coating. It is concluded that the fabricated bioactive composite scaffolds represent promising candidates for bone tissue engineering applications. © SAGE Publications.
An improved ant algorithm with LDA-based representation for text document clustering
(SAGE Publications Ltd, 2017) Onan A.; Bulut H.; Korukoglu S.
Document clustering can be applied in document organisation and browsing, document summarisation and classification. The identification of an appropriate representation for textual documents is extremely important for the performance of clustering or classification algorithms. Textual documents suffer from the high dimensionality and irrelevancy of text features. Besides, conventional clustering algorithms suffer from several shortcomings, such as slow convergence and sensitivity to the initial value. To tackle the problems of conventional clustering algorithms, metaheuristic algorithms are frequently applied to clustering. In this paper, an improved ant clustering algorithm is presented, where two novel heuristic methods are proposed to enhance the clustering quality of ant-based clustering. In addition, the latent Dirichlet allocation (LDA) is used to represent textual documents in a compact and efficient way. The clustering quality of the proposed ant clustering algorithm is compared to the conventional clustering algorithms using 25 text benchmarks in terms of F-measure values. The experimental results indicate that the proposed clustering scheme outperforms the compared conventional and metaheuristic clustering methods for textual documents. © Chartered Institute of Library and Information Professionals.
A feature selection model based on genetic rank aggregation for text sentiment classification
(SAGE Publications Ltd, 2017) Onan A.; KorukoGlu S.
Sentiment analysis is an important research direction of natural language processing, text mining and web mining which aims to extract subjective information in source materials. The main challenge encountered in machine learning method-based sentiment classification is the abundant amount of data available. This amount makes it difficult to train the learning algorithms in a feasible time and degrades the classification accuracy of the built model. Hence, feature selection becomes an essential task in developing robust and efficient classification models whilst reducing the training time. In text mining applications, individual filter-based feature selection methods have been widely utilized owing to their simplicity and relatively high performance. This paper presents an ensemble approach for feature selection, which aggregates the several individual feature lists obtained by the different feature selection methods so that a more robust and efficient feature subset can be obtained. In order to aggregate the individual feature lists, a genetic algorithm has been utilized. Experimental evaluations indicated that the proposed aggregation model is an efficient method and it outperforms individual filter-based feature selection methods on sentiment classification. © The Author(s) 2015.
TTC-3600: A new benchmark dataset for Turkish text categorization
(SAGE Publications Ltd, 2017) Klllnç D.; Özçift A.; Bozyigit F.; Ylldlrlm P.; Yücalar F.; Borandag E.
Owing to the rapid growth of the World Wide Web, the number of documents that can be accessed via the Internet explosively increases with each passing day. Considering news portals in particular, sometimes documents related to categories such as technology, sports and politics seem to be in the wrong category or documents are located in a generic category called others. At this point, text categorization (TC), which is generally addressed as a supervised learning task is needed. Although there are substantial number of studies conducted on TC in other languages, the number of studies conducted in Turkish is very limited owing to the lack of accessibility and usability of datasets created. In this paper, a new dataset named TTC-3600, which can be widely used in studies of TC of Turkish news and articles, is created. TTC-3600 is a well-documented dataset and its file formats are compatible with well-known text mining tools. Five widely used classifiers within the field of TC and two feature selection methods are evaluated on TTC-3600. The experimental results indicate that the best accuracy criterion value 91.03% is obtained with the combination of Random Forest classifier and attribute ranking-based feature selection method in all comparisons performed after pre-processing and feature selection steps. The publicly available TTC-3600 dataset and the experimental results of this study can be utilized in comparative experiments by other researchers. © Chartered Institute of Library and Information Professionals.

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