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This paper presents a novel hybrid series salp particle swarm optimization (SSPSO) algorithm for tracking the global maximum power point (GMPP) of the standalone battery charging systems under partial shading conditions (PSC). The photovoltaic (PV) characteristics such as power current (P-I) and power voltage (P-V) have a global peak and various local peaks with complicated shapes under PSC. Some conventional techniques failed to track accurately the GMPP under shaded conditions, therefore, the proposed SSPSO with its accuracy and performance of tracking nearly the GMPP is used and compared with other existing algorithms. DC-DC buck boost converter is used to adjust the impedance and match the proposed model with the output of the system. The same PV shaded patterns are applied with other conventional algorithms and the simulations results show that the novel hybrid SSPSO can quickly track the GMPP within a minor time, with high efficiency and moreover presents a high quality of tracked power as compared to the existing selected techniques. The proposed SSPSO presents the average tracking efficiency of 99.99%, which is highly required to be applied in the suburb areas or remoted areas where the partial shading repeatedly occurs in PV array due to the environment effects.

Introduction: Various graft materials have been used in the tympanoplasty technique. Cartilage grafts are being used increasingly in recent years. Objective: The aim of this study was to present the comparative outcomes of the perichondrium-preserved palisade island graft technique previously defined by ourselves. Methods: We retrospectively compared the hearing and graft success rates in 108 patients with chronic otitis media, who had undergone cartilage tympanoplasty, where both island and perichondrium-preserved palisade graft techniques were used. Results: The success rates among the study and the control groups with regard to graft take were 97% and 93%, respectively. No significant difference was observed between the groups with regard to the postoperative mean pure tone values, improvement in air-bone gaps and reduction in air-bone gaps to under 20 dB. However, better results were observed in the study group. Conclusion: The perichondrium-preserved palisade island graft technique is an easy method with high graft success rates and hearing outcomes.

2.5Bi(Zn0.5Zr0.5)O3−37.5BiScO3−60PbTiO3 (BZZ-BS-PT) ceramics were successfully textured in the [001] by templated grain growth (TGG) process using 5 vol% -oriented BaTiO3 (BT) plate-like templates. The templates were aligned in the matrix powder via tape casting and textured BZZ-BS-PT ceramics sintered at 1100°C for 3 h in air had a relative density of 98% and a Lotgering factor of 0.91. Chemically stable BT templates in Pb and Bi-rich BZZ-BS-PT system gave rise to the formation of highly oriented polycrystalline structure with larger block-like grains. A very high unipolar strain of 0.3% and low-field (

Objectives:We aimed to determine the seroprevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) in patients undergoing nasopharyngeal biopsy (NPB). Materials and Methods: The medical records of patients who had undergone NPB under local anesthesia between 2009 and 2020 were retrospectively analyzed in our clinic. The hepatitis B surface antigen (HBsAg), HCV antibody (anti-HCV), and HIV antibody (anti-HCV) were recorded in all patients. Age, gender, and pathology result of the patients were also recorded. The patients were divided into two groups (benign and malignant) according to the pathology results. The study included 666 patients with a mean age of 38.5±17.2 years (range, 6-89 years). Serology positivity was detected in 18 patients (2.7%) for HBsAg, in 4 patients (0.6%) for anti-HCV, and in 2 patients (0.3%) for anti-HIV. All serology-positive patients were older than eighteen. The HBV seropositivity rate was significantly higher in males (p=0.003). No statistically significant difference was found between male and female genders for HCV and HIV seropositivity (p>0.05). Reactive lymphoid hyperplasia (70.7%) and chronic inflammation (27.8%) were the most common results in the benign group. Undifferentiated Nasopharyngeal Carcinoma (58.9%) and B-cell non-Hodgkin lymphoma (17.8%) were the most common subtypes in the malignant group. There was no statistically significant difference between benign and malignant groups for HBV, HCV, and HIV seropositivity rates (p>0.05). Preoperative serological testing in patients undergoing NPB is required for increasing awareness of HBV, HCV, and HIV infections among healthcare personnels. Otolaryngologists must have the highest awareness of occupational infections deriving from blood and body fluids. It is necessary to take precaution measures including personal protective equipment during procedures. [Med-Science 2020; 9(4.000): 872-6]

This study targets to investigate the opinions and perceptions of the online and distance learners regarding to online proctored exams. A qualitative case study was employed to explore views of the participants related to the online proctored exam practice. The data were collected from 69 undergraduate distance learners via an online form. A content analysis approach were employed to analyze the data. As a result of the content analysis three themes namely, satisfaction, dissatisfaction, and exam administration emerged. The findings indicated that while online and distance learners were satisfied with the online proctored exams as they are secure, convenient, accessible, and reliable they also dissatisfied because of the technical problems and surveillance. Furthermore, the results also revealed that the administration of the online proctored exams needs to be reviewed. It is hoped that the findings will pave the way for future applications and research on the design and implementation of online proctored exams. Implications and future research suggestions are discussed.

This study aims to prepare a scale to determine the creativity levels of prospective teachers studying at the undergraduate level of science teaching. In this context, 15 questions, suitable for student's level from physics, chemistry, biology, astronomy and ecology sub-branches were prepared. The questions were assessed by 5 lecturers who were experts in their fields for their opinions. After the expert opinion, the number of questions was determined as 13 and pilot study was carried out with 95 pre-service teachers studying in Inonu University Faculty of Education Science Teacher Education. The data obtained from the pilot study were analyzed by using SPSS 21.0 statistical program according to Multi Surface Rasch Model. In order to determine the reliability of the scale, internal consistency coefficient of Cronbach's alpha was calculated and found 0.758. At the end of the research, the data was analyzed and the question number of the scale was determined as 10 according to the analysis results. Studies conducted on scientific creativity generally aimed to measure the scientific creativity of secondary school students. We believe that a deficiency in measuring the scientific creativity of undergraduate students at the academic level will be eliminated with the scale we developed.

The present study examined the online professional development practices of in-service English teachers. A sample of 184 in-service English teachers from various levels of education in Turkey participated in the study through an online questionnaire. The collected data were analyzed using SPSS to assess the teachers' utilization of the Internet for professional development, classroom activities, and collaboration with others. The results revealed that the participants extensively utilized the Internet for professional development, classroom activities, and collaboration with others. Furthermore, significant differences were found between participants' teaching levels and their use of the internet for collaboration, frequency of internet use, and internet use for classroom practices, as well as ICT training experiences and the use of the internet for overall professional development, classroom activities, and collaboration. The findings suggest that in-service English teachers prioritized and benefited from online professional development practices, and their ICT training influenced their use of the Internet for such practices.

Measuring students' interest and involvement in classroom activities at all stages of education, from preschool to upper secondary school, provides a better understanding of learning processes that enable the acquisition of abilities specific to a certain field. The purpose of this cross-age study was to investigate primary school students' involvement level in classroom activities. The sample consisted of 560 students studying in the first, second, third, and fourth grades at primary schools affiliated with a city in Turkey's inner Aegean area. The data were collected through "The Demographic Information Form" and "Leuven Involvement Scale". The research revealed that students in the 1st, 2nd, 3rd, and 4th grades in primary school had a moderate involvement level. It was found that there was a significant difference between the involvement levels of primary school students and the gender, course type, and professional experience of the teacher, but there was no significant difference between the grade levels of the students. It was recommended to use current methods and strategies to increase the level of involvement of students in classroom activities and to make arrangements to improve involvement in the learning environment.

We propose NTT implementations with each supporting at least one parameter of NTRU and one parameter of NTRU Prime. Our implementations are based on size-1440, size-1536, and size-1728 convolutions without algebraic assumptions on the target polynomial rings. We also propose several improvements for the NTT computation. Firstly, we introduce dedicated radix-(2, 3) butterflies combining Good–Thomas FFT and vector-radix FFT. In general, there are six dedicated radix-(2, 3) butterflies and they together support implicit permutations. Secondly, for odd prime radices, we show that the multiplications for one output can be replaced with additions/subtractions. We demonstrate the idea for radix-3 and show how to extend it to any odd prime. Our improvement also applies to radix-(2, 3) butterflies. Thirdly, we implement an incomplete version of Good–Thomas FFT for addressing potential code size issues. For NTRU, our polynomial multiplications outperform the state-of-the-art by 2.8%−10.3%. For NTRU Prime, our polynomial multiplications are slower than the state-of-the-art. However, the SotA exploits the specific structure of coefficient rings or polynomial moduli, while our NTT-based multiplications exploit neither and apply across different schemes. This reduces the engineering effort, including testing and verification.

Halkın maddi ve manevi bütün kültürel unsurlarını bilimsel bir tavırla araştırma disiplini olan halkbilimi, halk kültürünün her yönüyle ortaya konulması, çeşitli kuram ve teoriler ışığında araştırılması ve korunmasında önemli bir işlevi yerine getirir. Yakın tarihin kültürel atmosferi tasvir edilirken sivil toplum kuruluşları ve yerel medya unsurlarına özellikle odaklanmak, bütüncül bir bakış açısı oluşturabilmek adına önem arz etmektedir. Bu sebeple çok yönlü çalışmalarda basın, süreli yayın ve kurum-kuruluş kapsamındaki faaliyetlere özellikle odaklanma gereği kendini göstermektedir. Bu çalışmada 20.yy’da Van yöresinin kültürel zenginliğini ortaya çıkarma amaçlı, çoğu zaman kısıtlı imkanlarla yürütülen çalışmaların konu ve kapsamı ele alınmıştır. Van yöresinde gerçekleştirilen halk kültürü araştırma, tanıtım ve icra faaliyetlerinin sözlü kültür ürünleri, geçiş dönemi inanış ve uygulamaları ve maddi kültür vb. konulara odaklandığı, çalışmaların çoğu zaman bütüncül bir bakış açısından uzak şekilde tematik olarak yürütüldüğü görülmektedir. Ayrıca söz konusu konu çeşitliliğinde anonim halk edebiyatı ürünlerinin ağırlıklı olduğu dikkati çekmektedir. Yetişmiş insan kaynağının sınırlılığı sebebiyle çalışmalar akademik bir yaklaşımdan uzak şekilde, daha çok derleme gazeteci, öğretmen gibi meslek kollarından amatör bir ruhla gerçekleştirilmiştir.

Each branch of sports has its system, rules to be complied with, competition area, and forms. Adopting a sport and wanting to do it requires accepting all its rules from the beginning, obeying them, not opposing them, and defending them. Excessive desire to win which has been created in athletes for various reasons, or existing in the athlete's personality, affects the athlete's departure from sportive morality. The present study aimed to investigate sportspersonship behavior and moral disengagement in the sport of athletes who participated in international sports organizations. The quantitative method was used in the research. Relational screening model, which is one of the general survey models, was used for the purpose. The study group consisted of 164 national athletes who were selected according to non-random sampling methods (criterion sampling method). In order to examine the levels of disengagement from morality in sport, the "The Moral Disengagement in Sport Scale" developed by Boardley and Kavussuan (2008) and adapted to Turkish culture by Gürpınar (2015) was used. The "Multidimensional Sportspersonship Orientation Scale-Msos" developed by Vallerand et al. (1997) and adapted to Turkish by Sezen-Balçikanlı (2010) was used for the study of sportsmanship levels. Demographic variables such as gender, age, educational status, income status, the place where most of his life and sports year were analyzed, and no significant differences were found between disengagement from morality in sport and sportsmanship variables as a result of the analyses. The results of Pearson correlation analysis showed that there was a negative correlation between disengagement from morality in sport and sportsmanship views of individuals. According to the results, sportsmanship behaviors reduced as the levels of disengagement from morality increased. It can be said that the participants generally depend on the responsibilities and social norms in the sport and respect the rules and management. Even though it belongs to the sub-dimension of respect to the lowest average rivals, it was considered positive if it exceeds the average level.

Design in a solar food drying system is crucial for food drying performance. In order to make effective use of the sun, the use of air-heated solar collectors is gradually increasing in drying systems. Dryer room temperature and pressure distribution modelling is a very important factor for system design and product selection. In this study, the drying air speed, drying temperature, and product moisture content values of a solar drying system were numerically modelled in a time dependent manner. In numerical analysis, temperature and drying air velocity were defined as variable under initial and boundary conditions. Polynomial equations based on time obtained from drying room inlet temperature and drying air velocity data were used. The R2 values of these equations were calculated as 0.96 and 0.91, respectively. COMSOL multiphysics program was used for temperature values, drying air velocity, product moisture content values and drying chamber pressure values modelling. Depending on the position of the sun and the time, the drying chamber inlet temperature values and air velocity values have been change. During the drying process of the product, moisture content values, heat and mass transfer values, drying efficiency values, diffusion coefficient and activation energy values were examined. Experimental data and computed fluid dynamics analysis (CFD) data were compared. Using the CFD numerical analysis program, the drying room temperature, moisture content and air velocity values were modelled with mean absolute percent error (MAPE) of 5.34%, 3.74% and 6.30%, respectively.

In this study, performance of the blade profiles which was developed numerically and parametrically was examined experimentally for vertical axis wind turbine. In the parametric optimization study, angle of attack, mean (camber) line and thickness were taken as parameter, and the profile was optimized by using Ansys/Response Surface Optimization tool. After that, in the numerical optimization study, the lift and drag coefficients were taken as parameters and the profile was optimized and the blade profiles of NACA0012-α and NACA0012-β, which would make the lift-to-drag ratio maximum, were obtained. The developed profiles were produced by 3D printer and the power data was measured experimentally for 3, 4 and 5 bladed turbines. The highest power was obtained in the 4-bladed turbine for all profiles. The power coefficient of 0.19 was obtained from a reference profile, while power coefficient of 0.24 was obtained from NACA0012-α profile and 0.30 from NACA0012-β profile. The blade profile derived by numerical optimization reached 25% higher power coefficient than the blade profile derived by parametric optimization. It is found that lift coefficient on the power coefficient of the vertical axis wind turbine is more dominant than the drag coefficient.

BACKGROUND: Selective lung intubation is a life-saving procedure in emergency departments. While various equipment can be used in selective lung intubation, most of this equipment is not readily available; therefore, single-lumen endotracheal intubations are performed for rapid interventions.MATERIALS AND METHODS: This study was designed as a randomized, prospective, cross-over study using the 90° rotation technique for selective intubation on a manikin model with and without endotracheal tube introducer (ETI) in difficult airway settings. Forty-six emergency physicians were included in the study. The primary outcome was evaluating time to selective intubations, and secondary outcomes were first and second attempt success rates and the self-perceived difficulty level of each method according to the participants.RESULTS: The mean time to the first successful endotracheal intubation was significantly longer for both right selective and left selective intubations with ETI utilization than without ([39.71 ± 9.83 vs. 21.86 ± 5.94 s], [P < 0.001]), ([42.2 ± 10.81 vs. 26.23 ± 7.97 s], [P < 0.001], respectively). The first-pass success rate did not differ for right selective intubation with or without an ETI (45/46 [97.8%] and 45/46 [97.8%], respectively). However, the first-pass success rate for left selective intubation was significantly higher with ETI as compared to without an ETI (30/46 [65.2%] and 13/46 [28.3%], respectively) (P < 0.001).CONCLUSIONS: While the success rates of right selective intubation were the same, the left selective intubation success rates with ETI are higher than the styletted endotracheal tube, which can be strong evidence for this method's applicability in practice. Expanding the use of ETI and increasing the experience of the practitioners can contribute to further success.

In this study, the pressure changes in the internal flow in pipes of different material types were investigated experimentally and numerically. For this study, 2000 mm long pipes made of 5 different materials were used. Different Reynolds numbers (Re = 45832,12- 51276,56) were obtained by changing the fluid flow rate. Pressure change along the pipe with the change of the Reynolds number was experimentally observed. The flow rate change intervals of the flow are adjusted by changing the filling times of a fixed volume water tank. The 3D model of the experiment set was created in SOLIDWORKS 2018 and ANSYS FLUENT 18.1 numerical analysis program was used for the numerical model. Experimental data obtained for aluminum smooth pipes are modeled with less than 1% error by numerical analysis. The experiment set was verified by numerical analysis. Other pipes were mounted on this test set and pressure changes along the pipe and with time were experimentally observed. The suitability of flow rate and pressure measurement ranges and the accuracy of classification were supported by the ANOVA technique analysis method. As a result of, appropriate flow variation, pipe diameter ranges and pipe material classifications are presented as a contribution to the literature. It has been observed that pipe materials can be classified as hard metals (iron, galvanized steel, etc.), soft metals (copper, aluminum, etc.) and plastic (PPRC, etc.).

Pertrochanteric fractures (TF) due to osteoporosis constitute nearly half of all proximal femur fractures. TFs are treated with a surgical approach and fracture fixation is achieved using metallic fixation devices. Poor quality cancellous bone in osteoporotic patients makes anchorage of a fixation device challenging, which can lead to failure of the fracture fixation. Methods to reinforce the bone-implant interface using bone cement (PMMA) and other calcium phosphate cements in TFs have been described earlier but a clear evidence on the advantage of using such biomaterials for augmentation is weak. Furthermore, there is no standardized technique for delivering these biomaterials at the bone-implant interface. In this study, we firstly describe a method to deliver a calcium sulphate/hydroxyapatite (CaS/HA) based biomaterial for the augmentation of a lag-screw commonly used for TF fixation. We then used an osteoporotic Sawbones model to study the consequence of CaS/HA augmentation on the immediate mechanical anchorage of the lag-screw to osteoporotic bone. Finally, as a proof-of-concept, the method of delivering the CaS/HA biomaterial at the bone-implant interface as well as spreading of the CaS/HA material at this interface was tested in patients undergoing treatment for TF as well as in donated femoral heads. The mechanical testing results indicated that the CaS/HA based biomaterial increased the peak extraction force of the lag-screw by 4 times compared with un-augmented lag-screws and the results were at par with PMMA. The X-ray images from the patient series showed that it was possible to inject the CaS/HA material at the bone-implant interface without applying additional pressure and the CaS/HA material spreading was observed at the interface of the lag-screw threads and the bone. Finally, the spreading of the CaS/HA material was also verified on donated femoral heads and micro-CT imaging indicated that the entire length of the lag-screw threads was covered with the CaS/HA biomaterial. In conclusion, we present a novel method for augmenting a lag-screw in TFs, which could potentially reduce the risk of fracture fixation failure and reoperation in fragile osteoporotic patients.

Software evaluation and selection have begun to be addressed as a topic title along with the fact that microcomputers and then personal computers have become widespread and have been used in the operations of businesses. In this study, it was focused on the selection of software for identifying the physical effect distances of the explosion, fire, and toxic emission, which is an important need for industrial institutions containing, using or storing hazardous chemicals. The evaluation and selection of software for the Hazard Analysis and Consequence Modeling (HACM) of potential accidents was studied at first. In means of methodology, questionnaires consisting of original questions were applied to the experts. The results obtained from questionnaires according to the Likert scale, were converted into Analytical Hierarchy Process (AHP) suggestion matrices. In this way, the inconsistency problem in the pairwise comparison matrices was eliminated. As a result, evaluation and selection were made among the HACM software.

Although the need for fossil fuels, which is the energy source of internal combustion engines that are widely used in the transportation sector, increases continuously, the reserves are continuously decreasing. However, the fuel combustion reaction results in large damages to the environment due to effects of exhaust gas emissions. For these reasons, vehicles that work with alternative energy sources are being developed. In this context, the development of fully electric vehicles is being carried out today. In-wheel electric motor studies are one of the most fully electric vehicle developments. In scope of this study, frontal collision of a pre-engineered electromobile vehicle to straight rigid wall is examined via ANSYS Workbench LS-DYNA computer aided engineering (CAE) software. Since the analysis is a time-dependent dynamic analysis due to its structure, it has been performed by using explicit finite element method. The data of the acceleration, force and deflection values formed by collision effect on the head, chest and femur of the dummy were obtained by placing dummy into the vehicle model. The data obtained were compared with the critical limit values accepted by various authorities and the inferences were made regarding the injury status of dummy.

Abstract Background Metastatic colorectal cancer (CRC) continues to be a major health problem, and current treatments are primarily for disease control and palliation of symptoms. In this study, we developed a precision medicine strategy to discover novel therapeutics for patients with CRC. Methods Six matched low-passage cell lines and patient-derived xenografts (PDX) were established from CRC patients undergoing resection of their cancer. High-throughput drug screens using a 119 FDA-approved oncology drug library were performed on these cell lines, which were then validated in vivo in matched PDXs. RNA-Seq analysis was then performed to identify predictors of response. Results Our study revealed marked differences in response to standard-of-care agents across patients and pinpointed druggable pathways to treat CRC. Among these pathways co-targeting of fibroblast growth factor receptor (FGFR), SRC, platelet derived growth factor receptor (PDGFR), or vascular endothelial growth factor receptor (VEGFR) signaling was found to be an effective strategy. Molecular analyses revealed potential predictors of response to these druggable pathways. Conclusions Our data suggests that the use of matched low-passage cell lines and PDXs is a promising strategy to identify new therapies and pathways to treat metastatic CRC.

Varicocele might cause deterioration in Leydig cell functions, and it is a significant risk factor for hypogonadism. Some controversial issues have been raised in the treatment of hypogonadal men with varicoceles. Symptomatic hypogonadal men with varicoceles have two options: testosterone replacement therapy or varicocele treatment. Both approaches have some advantages and disadvantages. This review summarizes the effect of varicoceles on total plasma testosterone level and addresses whether varicocele repair is effective to improve testosterone levels in hypogonadal men with varicoceles. Experience from large clinical studies in the literature suggests that varicocele repair may increase serum testosterone level in men with varicoceles and testosterone deficiency. Varicocele repair could be offered to men with clinically palpable varicocele and hypogonadism. As the treatment method, microsurgical varicocele repair could be preferred to provide the best improvement. Another advantage of varicocele repair for hypogonadism, instead of exogenous testosterone treatment, is its ability to preserve the fertility status in men who may desire a child in the future. However, further studies are required to clarify varicocel-related Leydig cell dysfunction and to advise hypogonadal patients about the sufficient effectiveness of varicocele repair.

Küreselleşmenin hızla arttığı günümüzde rekabet edebilirliğin temeli bilgiye dayanmaktadır. Bilgi, Ar-Ge çalışmaları ile sistematik hale getirilerek bilim ve teknolojiye dönüşür. Bir ülkenin kalkınması katma değer üretmesi, istihdam sağlayabilmesi, üretimlerini sürekli artırarak devam ettirebilmesi ancak bilgi birikiminin artması ve artan bilginin bilim ve teknolojiye dönüştürülmesi ile mümkündür. Ürün ve hizmet çeşitliliğinin çok fazla olduğu göz önüne alındığında ülkelerin ve üreticilerin bu faaliyetlerini sürdürebilmeleri ve rekabet edebilmeleri için yenilikler ortaya koyması gerekmektedir. Bu konuda araştırma ve geliştirme (Ar-Ge) büyük önem taşımaktadır. Ar-Ge, hali hazırda bulunan bilgilerden yeni ürün, yeni üretim yöntemlerinin geliştirilmesi veya yeni teknolojilerin, ürünlerin, üretim yöntemlerinin elde edilmesi olarak tanımlanabilir. Diğer ülkelerde olduğu gibi ülkemiz de Ar-Ge yatırımlarını teşvik etmekte ve Ar-Ge yatırımlarına destek vermektedir. Bu kapsamda birçok kurum ve kuruluş girişimcilerin, firmaların, akademisyenlerin Ar-Ge projelerini sağladığı katma değer oranında desteklemektedir. Ar-ge boyutunda desteğin belirlenmesinde etkin olacak katma değer ise fayda olarak değerlendirilebilir. Bu amaçla desteklerin etkin bir şekilde kullanılması göz önüne alınarak, çalışmamızda Ar-Ge projelerinin seçiminin yapıldığı bir yarışmada projelerin değerlendirme süreci ele alınmıştır. UTA yöntemi marjinal faydayı dikkate alan yapısı ve doğrusal programlama yaklaşımını içermesi nedeniyle tercih edilmiştir. Yöntemin çözüm aşamasında elde edilen matematiksel modelin çözümü için de GAMS Programından yararlanılmıştır. Bulunan çözümün fayda temelli olmasından dolayı projelerin daha etkin ve doğru şekilde sıralanmasına destek sağlayabileceği gösterilmeye çalışılmıştır.

Küreselleşmenin hızla arttığı günümüzde rekabet edebilirliğin temeli bilgiye dayanmaktadır. Bilgi, Ar-Ge çalışmaları ile sistematik hale getirilerek bilim ve teknolojiye dönüşür. Bir ülkenin kalkınması katma değer üretmesi, istihdam sağlayabilmesi, üretimlerini sürekli artırarak devam ettirebilmesi ancak bilgi birikiminin artması ve artan bilginin bilim ve teknolojiye dönüştürülmesi ile mümkündür. Ürün ve hizmet çeşitliliğinin çok fazla olduğu göz önüne alındığında ülkelerin ve üreticilerin bu faaliyetlerini sürdürebilmeleri ve rekabet edebilmeleri için yenilikler ortaya koyması gerekmektedir. Bu konuda araştırma ve geliştirme (Ar-Ge) büyük önem taşımaktadır. Ar-Ge, hali hazırda bulunan bilgilerden yeni ürün, yeni üretim yöntemlerinin geliştirilmesi veya yeni teknolojilerin, ürünlerin, üretim yöntemlerinin elde edilmesi olarak tanımlanabilir. Diğer ülkelerde olduğu gibi ülkemiz de Ar-Ge yatırımlarını teşvik etmekte ve Ar-Ge yatırımlarına destek vermektedir. Bu kapsamda birçok kurum ve kuruluş girişimcilerin, firmaların, akademisyenlerin Ar-Ge projelerini sağladığı katma değer oranında desteklemektedir. Ar-ge boyutunda desteğin belirlenmesinde etkin olacak katma değer ise fayda olarak değerlendirilebilir. Bu amaçla desteklerin etkin bir şekilde kullanılması göz önüne alınarak, çalışmamızda Ar-Ge projelerinin seçiminin yapıldığı bir yarışmada projelerin değerlendirme süreci ele alınmıştır. UTA yöntemi marjinal faydayı dikkate alan yapısı ve doğrusal programlama yaklaşımını içermesi nedeniyle tercih edilmiştir. Yöntemin çözüm aşamasında elde edilen matematiksel modelin çözümü için de GAMS Programından yararlanılmıştır. Bulunan çözümün fayda temelli olmasından dolayı projelerin daha etkin ve doğru şekilde sıralanmasına destek sağlayabileceği gösterilmeye çalışılmıştır.

Background and purpose — Obesity defined as increased BMI is commonly associated with higher revision rates following total knee arthroplasty (TKA). We examined the effect of BMI on the rate of revision after TKA, for both infection and other reasons, and analyzed weight and height separately to provide better understanding of the risk profile. Patients and methods — The Swedish national knee arthroplasty register was used to identify 107,228 patients operated with primary TKA for osteoarthritis between 2009 and 2017. Cox proportional hazards regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for BMI (categories: < 18.5, 18.5–24.9, 25–29.9, 30–34.9, 35–39.9, ≥ 40), weight (categories: < 65, 65–89, 90–114, ≥ 115 kg) and height (categories: < 160, 160–179, ≥ 180 cm Results — There were 2,503 revisions in the follow-up period; 1,036 for infection and 1,467 for other reasons. Higher BMI and weight categories were associated with a similar and statistically significantly increased risk of revision for all causes and for infection. The risk of revision for infection was almost twice in the highest BMI and highest weight group: HR = 3.4 (CI 2.3–4.7) and HR = 3.1 (CI 2.5–3.9) respectively. For BMI and weight categories there was no statistically significant association between revision for other reasons than infection, contrary to the tallest height category where it was statistically significant (HR = 1.3 [CI 1.1–1.5]). Interpretation — BMI, weight, and height may be associated with different types of risks for revision following TKA.