In permanent magnet synchronous motor drives, d-q current errors are examined using hysteresis controllers. The inverter is switched based on the hysteresis controller responses, to limit current errors, and thereby reducing current ripple. But, due to the faster current dynamic characteristics, switching the current errors within the hysteresis band becomes difficult. This results in d-q current ripples and harmonics. In this paper, two current error-limiting schemes are proposed. In the first scheme, current errors are switched within the band using additional control parameters (dynamic response of q-axis current), to select the control space vector from a switching table. Whereas in the second scheme, a duty ratio regulator is designed to achieve minimum q-axis current error. The proposed works are simulated in MATLAB/Simulink and verified through experimentation. Since the current ripple and harmonics are also reduced, the thermal impact of these performance pa-rameters on the power inverter is also studied.
{"title":"New Steady State Current Error Limiters for PMSM Drives","authors":"Hemantha Kumar Ravi, Lenın N C","doi":"10.35378/gujs.1253423","DOIUrl":"https://doi.org/10.35378/gujs.1253423","url":null,"abstract":"In permanent magnet synchronous motor drives, d-q current errors are examined using hysteresis controllers. The inverter is switched based on the hysteresis controller responses, to limit current errors, and thereby reducing current ripple. But, due to the faster current dynamic characteristics, switching the current errors within the hysteresis band becomes difficult. This results in d-q current ripples and harmonics. In this paper, two current error-limiting schemes are proposed. In the first scheme, current errors are switched within the band using additional control parameters (dynamic response of q-axis current), to select the control space vector from a switching table. Whereas in the second scheme, a duty ratio regulator is designed to achieve minimum q-axis current error. The proposed works are simulated in MATLAB/Simulink and verified through experimentation. Since the current ripple and harmonics are also reduced, the thermal impact of these performance pa-rameters on the power inverter is also studied.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"57 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139323739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gender recognition based on the hand image is used in computer vision for human-computer communication, hand-based authentication, and identification systems. Beside this, gender recognition may be applied for criminal investigations, visual surveillance, and other legal purposes. The traditional manual methods require a lot of time and are susceptible to variable fluctuations. However, for low amounts of data, the deep-learning models are going to be overfitted. In this regard, this work proposes a shallow convolutional neural network (CNN) with a regularization method. Here, different gender recognition models are built to detect the gender individually from dorsal and palmar hand images. For that, the 11K hand dataset is divided into four labels, i.e., men dorsal side, women dorsal side, men palm side, and women palm side. These data have been pre-processed by resizing and scaling. Furthermore, a model is developed for recognizing gender from the real time data. According to the experimental results, the model developed for the dorsal hand images outperforms the other proposed models and the current state-of-the-art.
{"title":"Shallow Convolutional Neural Network for Gender Classification Based on Hand","authors":"Md. KHALİLUZZAMAN","doi":"10.35378/gujs.1246486","DOIUrl":"https://doi.org/10.35378/gujs.1246486","url":null,"abstract":"Gender recognition based on the hand image is used in computer vision for human-computer communication, hand-based authentication, and identification systems. Beside this, gender recognition may be applied for criminal investigations, visual surveillance, and other legal purposes. The traditional manual methods require a lot of time and are susceptible to variable fluctuations. However, for low amounts of data, the deep-learning models are going to be overfitted. In this regard, this work proposes a shallow convolutional neural network (CNN) with a regularization method. Here, different gender recognition models are built to detect the gender individually from dorsal and palmar hand images. For that, the 11K hand dataset is divided into four labels, i.e., men dorsal side, women dorsal side, men palm side, and women palm side. These data have been pre-processed by resizing and scaling. Furthermore, a model is developed for recognizing gender from the real time data. According to the experimental results, the model developed for the dorsal hand images outperforms the other proposed models and the current state-of-the-art.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135924968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, convergences of a filter and a net have been characterized through ideal on topological spaces. Furthermore, we characterized the local function in an ideal topological space in terms of convergence of filter. Using Zorn's Lemma, we have found a maximal element in the collection of all proper ideals on a nonempty set which is called maximal ideal. We provide a convenient characterization of maximal ideals. We also consider simple properties of the image of an ideal, a net, and various local functions under a homeomorphism.
{"title":"Characterizations of Filter Convergent in Terms of Ideal","authors":"Shyamapada MODAK, Kulchhum KHATUN, Jiarul HOQUE","doi":"10.35378/gujs.967261","DOIUrl":"https://doi.org/10.35378/gujs.967261","url":null,"abstract":"In this paper, convergences of a filter and a net have been characterized through ideal on topological spaces. Furthermore, we characterized the local function in an ideal topological space in terms of convergence of filter. Using Zorn's Lemma, we have found a maximal element in the collection of all proper ideals on a nonempty set which is called maximal ideal. We provide a convenient characterization of maximal ideals. We also consider simple properties of the image of an ideal, a net, and various local functions under a homeomorphism.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135958157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of this study is to develop a controlled Fluconazole and Naproxen releasing system for cartilage repair. A series of interpenetrating polymer network (IPN) type of hydrogels were prepared by using 2-Hydroxyethyl methacrylate (HEMA) and gelatin in different ratios. The hydrogels were synthesized by using ammonium persulfate (APS) and sodium metabisulfite (SBS) as initiator pair and ethylene glycol dimethacrylate (EGDMA) and glutaraldehyde (GA) as cross linkers. The prepared hydrogels were characterized via hydrogel formation and swelling/degradation measurements, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM) analysis. From swelling tests, it is observed that semi-IPN hydrogels swell much more than full-IPNs which crosslinked by two agents, EGDMA and GA. The higher ratios of HEMA/gelatin negatively affect swelling values. In general, the IPN hydrogel discs were not affected by the variation of temperature. The release studies of Fluconazole and Naproxen were performed at 37 ⁰C and it is found that the swelling and release profiles were similar to each other. The releases of drugs increase rapidly at first and then complies nearly 36 h-48 h. Because of the looser and porous structure, semi-IPN hydrogels have higher release values than full-IPNs.
{"title":"Development of a Controlled Released System Based on IPN Types Hydrogel for Cartilage Repair","authors":"Evrim SEVER, Mehlika PULAT","doi":"10.35378/gujs.1295326","DOIUrl":"https://doi.org/10.35378/gujs.1295326","url":null,"abstract":"The aim of this study is to develop a controlled Fluconazole and Naproxen releasing system for cartilage repair. A series of interpenetrating polymer network (IPN) type of hydrogels were prepared by using 2-Hydroxyethyl methacrylate (HEMA) and gelatin in different ratios. The hydrogels were synthesized by using ammonium persulfate (APS) and sodium metabisulfite (SBS) as initiator pair and ethylene glycol dimethacrylate (EGDMA) and glutaraldehyde (GA) as cross linkers. The prepared hydrogels were characterized via hydrogel formation and swelling/degradation measurements, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM) analysis. From swelling tests, it is observed that semi-IPN hydrogels swell much more than full-IPNs which crosslinked by two agents, EGDMA and GA. The higher ratios of HEMA/gelatin negatively affect swelling values. In general, the IPN hydrogel discs were not affected by the variation of temperature. The release studies of Fluconazole and Naproxen were performed at 37 ⁰C and it is found that the swelling and release profiles were similar to each other. The releases of drugs increase rapidly at first and then complies nearly 36 h-48 h. Because of the looser and porous structure, semi-IPN hydrogels have higher release values than full-IPNs.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136364205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The current paper is concerned with fuzzy controllers employing neural networks to implement control over power electronics systems committed to power quality improvement in a distribution grid. An optimization method technique for tuning fuzzy PI controller gains is introduced to improve a Hybrid Indirect Matrix Converter's control with a flying capacitor three-level inverter (HIMC), and it is connected via an RL filter to the power grid (PG). The harmonics are identified by an Artificial Neural Network (ANN). The effectiveness of this method is shown in the simulation results by MATLAB/Simulink ( Simscap, simpower blocks).
{"title":"ANN Identification technique and fuzzy PI Control of a Hybrid Indirect Matrix Converter with a Flying Capacitor three level Inverter in Power Active Filtering Application","authors":"Taki Eddine AMEUR, Aissa AMEUR, Benalia ATALLAH","doi":"10.35378/gujs.1001559","DOIUrl":"https://doi.org/10.35378/gujs.1001559","url":null,"abstract":"The current paper is concerned with fuzzy controllers employing neural networks to implement control over power electronics systems committed to power quality improvement in a distribution grid. An optimization method technique for tuning fuzzy PI controller gains is introduced to improve a Hybrid Indirect Matrix Converter's control with a flying capacitor three-level inverter (HIMC), and it is connected via an RL filter to the power grid (PG). The harmonics are identified by an Artificial Neural Network (ANN). The effectiveness of this method is shown in the simulation results by MATLAB/Simulink ( Simscap, simpower blocks).","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135895721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There is a growing attention in circular economy through researchers, enterprises and goverments. The idea of circular economy is not to give any harm to enviroment while using material till end of its life and keeping it as much as possible in the cycle. From this point of view, to keep the material in cycle might be possible with a well-designed logistics infrastructure. In this study, the small and medium size enterprises (SMEs) that make sales through e-commerce and the way of handling e-commerce returns are brought forward. The case study created for footware industry in Istanbul and a network design is proposed. Afterwards, a linear programming is used to calculated to minimize cost. This study gives a clear and simple solution for SMEs to minimize the cost for handling return products while keeping the returns in the cycle.
{"title":"Circular Supply Chain Network Design for E-Commerce","authors":"Batuhan KOCAOĞLU, Meliha BULUT","doi":"10.35378/gujs.1234548","DOIUrl":"https://doi.org/10.35378/gujs.1234548","url":null,"abstract":"There is a growing attention in circular economy through researchers, enterprises and goverments. The idea of circular economy is not to give any harm to enviroment while using material till end of its life and keeping it as much as possible in the cycle. From this point of view, to keep the material in cycle might be possible with a well-designed logistics infrastructure. In this study, the small and medium size enterprises (SMEs) that make sales through e-commerce and the way of handling e-commerce returns are brought forward. The case study created for footware industry in Istanbul and a network design is proposed. Afterwards, a linear programming is used to calculated to minimize cost. This study gives a clear and simple solution for SMEs to minimize the cost for handling return products while keeping the returns in the cycle.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135781970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The performance of inductive learners can be negatively affected by high-dimensional datasets. To address this issue, feature selection methods are used. Selecting relevant features and reducing data dimensions is essential for having accurate machine learning models. Stability is an important criterion in feature selection. Stable feature selection algorithms maintain their feature preferences even when small variations exist in the training set. Studies have emphasized the importance of stable feature selection, particularly in cases where the number of samples is small and the dimensionality is high. In this study, we evaluated the relationship between stability measures, as well as, feature selection stability and classification accuracy, using the Pearson Product-Moment Correlation Coefficient. We conducted an extensive series of experiments using five filter and two wrapper feature selection methods, three classifiers for subset and classification performance evaluation, and eight real-world datasets taken from two different data repositories. We measured the stability of feature selection methods using a total of twelve stability metrics. Based on the results of correlation analyses, we have found that there is a lack of substantial evidence supporting a linear relationship between feature selection stability and classification accuracy. However, a strong positive correlation has been observed among several stability metrics.
{"title":"An Empirical Evaluation of Feature Selection Stability and Classification Accuracy","authors":"Mustafa Büyükkeçeci̇, M. C. Okur","doi":"10.35378/gujs.998964","DOIUrl":"https://doi.org/10.35378/gujs.998964","url":null,"abstract":"The performance of inductive learners can be negatively affected by high-dimensional datasets. To address this issue, feature selection methods are used. Selecting relevant features and reducing data dimensions is essential for having accurate machine learning models. Stability is an important criterion in feature selection. Stable feature selection algorithms maintain their feature preferences even when small variations exist in the training set. Studies have emphasized the importance of stable feature selection, particularly in cases where the number of samples is small and the dimensionality is high. In this study, we evaluated the relationship between stability measures, as well as, feature selection stability and classification accuracy, using the Pearson Product-Moment Correlation Coefficient. We conducted an extensive series of experiments using five filter and two wrapper feature selection methods, three classifiers for subset and classification performance evaluation, and eight real-world datasets taken from two different data repositories. We measured the stability of feature selection methods using a total of twelve stability metrics. Based on the results of correlation analyses, we have found that there is a lack of substantial evidence supporting a linear relationship between feature selection stability and classification accuracy. However, a strong positive correlation has been observed among several stability metrics.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"8 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139348703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nathan DİBAL, Musa SAMAİLA CHİROMA, Martha ATTAH, Sunday MANYE
Quercetin is a flavonoid with a great capability of crossing the blood-brain barrier. It is reported to exert numerous beneficial effects on both animal and human health. The study evaluates the effects of onion waste quercetin (OWQ) on the histology of the hippocampus and dentate gyrus of mice. Twenty mice were assigned into four groups (n=5). The groups were given distilled water, and OWQ at 95mg/kg, 190mg/kg, and 380mg/kg respectively for 28 days. The brain of each mouse was harvested afterward, weighed, and processed for light microscopy. The normal and degenerating cells in the dentate gyrus and hippocampus Cornu Ammonis (CA1 & CA3) were counted. The micrographs of the dentate gyrus showed normal molecular, granular, and polymorphic layers in the control mice, as well as the mice, treated with OWQ with few degenerating cells in the granular layer of OWQ-treated (190mg/kg) mice. The CA3 area of the hippocampus showed normal molecular and polymorphic layers in OWQ-treated mice. However, the granular layer of the mice that received OWQ at 190mg/kg showed numerous degenerating cells. OWQ especially at 95mg/kg was found to significantly increase the number of normal cells in the dentate gyrus and hippocampus (CA1 & CA3) of the brain compared to the control at P< .05. It also significantly decreased degenerating cells compared to the control (P< .05). In conclusion, onion waste quercetin, especially at 95mg/kg was found to maintain the pool of normal cells within the dentate gyrus and hippocampus of mice brain.
{"title":"Effects of Sub-acute Administration of Onion Waste Quercetin on the Hippocampus of Mice: A Histological Approach","authors":"Nathan DİBAL, Musa SAMAİLA CHİROMA, Martha ATTAH, Sunday MANYE","doi":"10.35378/gujs.1272285","DOIUrl":"https://doi.org/10.35378/gujs.1272285","url":null,"abstract":"Quercetin is a flavonoid with a great capability of crossing the blood-brain barrier. It is reported to exert numerous beneficial effects on both animal and human health. The study evaluates the effects of onion waste quercetin (OWQ) on the histology of the hippocampus and dentate gyrus of mice. Twenty mice were assigned into four groups (n=5). The groups were given distilled water, and OWQ at 95mg/kg, 190mg/kg, and 380mg/kg respectively for 28 days. The brain of each mouse was harvested afterward, weighed, and processed for light microscopy. The normal and degenerating cells in the dentate gyrus and hippocampus Cornu Ammonis (CA1 & CA3) were counted. The micrographs of the dentate gyrus showed normal molecular, granular, and polymorphic layers in the control mice, as well as the mice, treated with OWQ with few degenerating cells in the granular layer of OWQ-treated (190mg/kg) mice. The CA3 area of the hippocampus showed normal molecular and polymorphic layers in OWQ-treated mice. However, the granular layer of the mice that received OWQ at 190mg/kg showed numerous degenerating cells. OWQ especially at 95mg/kg was found to significantly increase the number of normal cells in the dentate gyrus and hippocampus (CA1 & CA3) of the brain compared to the control at P< .05. It also significantly decreased degenerating cells compared to the control (P< .05). In conclusion, onion waste quercetin, especially at 95mg/kg was found to maintain the pool of normal cells within the dentate gyrus and hippocampus of mice brain.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135236328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Double skin facades (DSF) aim to save energy reducing the heat losses in buildings. They are visually appeal while allowing to use daylight efficiently. Such facade systems can reduce glare and distribute daylight evenly in the interior when compared to conventional facade systems. That is a result of cavities between two glass facades and locating sunshading elements in them, although this system provides a high level of transparency. As their primary purpose of application is to ensure thermal performance and ventilation, most studies in literature have focused on these. However, to construct and maintain a holistic point of view in building performance, researchers and professionals need to take into account the integration of daylight use and analysis in such facades. This study aims to analyse daylight performance implemented studies in relation to these systems and presents a comprehensive and recent review on integration of daylight use and analysis. Recent studies are shown in tabulated form and interpreted in detail with graphics. considering their methodologies, daylight parameters and findings. Results show that the daylight parameter is one of the most important issues that architects or designers should consider from the moment they start the design, and they should make their designs based on the optimum penetration of daylight into the building. This review can contribute to literature in calling attention to daylight studies in DSF. It provides feedback information on how recent researches and technological developments in DSF can let them benefit from daylight more efficiently. That makes more and further improvements in such facade system design. Thus, DSF helps to build an integrated building performance approach in achieving sustainability.
{"title":"Integration of Daylight Use and Analysis in Double Skin Facades: A Literature Review","authors":"Mustafa Serhan Ünlütürk, Tuğçe Kazanasmaz","doi":"10.35378/gujs.1243933","DOIUrl":"https://doi.org/10.35378/gujs.1243933","url":null,"abstract":"Double skin facades (DSF) aim to save energy reducing the heat losses in buildings. They are visually appeal while allowing to use daylight efficiently. Such facade systems can reduce glare and distribute daylight evenly in the interior when compared to conventional facade systems. That is a result of cavities between two glass facades and locating sunshading elements in them, although this system provides a high level of transparency. As their primary purpose of application is to ensure thermal performance and ventilation, most studies in literature have focused on these. However, to construct and maintain a holistic point of view in building performance, researchers and professionals need to take into account the integration of daylight use and analysis in such facades. This study aims to analyse daylight performance implemented studies in relation to these systems and presents a comprehensive and recent review on integration of daylight use and analysis. Recent studies are shown in tabulated form and interpreted in detail with graphics. considering their methodologies, daylight parameters and findings. Results show that the daylight parameter is one of the most important issues that architects or designers should consider from the moment they start the design, and they should make their designs based on the optimum penetration of daylight into the building. This review can contribute to literature in calling attention to daylight studies in DSF. It provides feedback information on how recent researches and technological developments in DSF can let them benefit from daylight more efficiently. That makes more and further improvements in such facade system design. Thus, DSF helps to build an integrated building performance approach in achieving sustainability.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"5 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139351768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peptide biomolecules have important bioactivities and hence their use in drug design and development studies has increased in recent years. Conotoxins are natural peptides that obtained from cone snail venoms and have the potential to be used for chronic pain treatment, Parkinson's disease, schizophrenia, obesity and cancer due to their effects on the nervous system. However, their use as medicines has been limited as they can be easily broken down by many proteolytic enzymes in the body. Several modification methods are used to overcome these disadvantages. Cyclization of the peptide backbone is one such method and has been used to stabilize various linear peptides. In this study, the N- and C-termini of α-conotoxin TxID with two disulfide bridges were joined using a six amino acid long GGAAGG linker peptide chain to cyclize the peptide backbone and the serum stability of the cyclized peptide was examined. The cyclic TxID peptide remained intact about 50% in human serum after 24 hours.
{"title":"Head-to-Tail Cyclization of α-Conotoxin TxID Leads to Enhanced Stability in Serum","authors":"Nurcan BİÇEN KARAKOÇ, Muharrem Akcan","doi":"10.35378/gujs.1263833","DOIUrl":"https://doi.org/10.35378/gujs.1263833","url":null,"abstract":"Peptide biomolecules have important bioactivities and hence their use in drug design and development studies has increased in recent years. Conotoxins are natural peptides that obtained from cone snail venoms and have the potential to be used for chronic pain treatment, Parkinson's disease, schizophrenia, obesity and cancer due to their effects on the nervous system. However, their use as medicines has been limited as they can be easily broken down by many proteolytic enzymes in the body. Several modification methods are used to overcome these disadvantages. Cyclization of the peptide backbone is one such method and has been used to stabilize various linear peptides. In this study, the N- and C-termini of α-conotoxin TxID with two disulfide bridges were joined using a six amino acid long GGAAGG linker peptide chain to cyclize the peptide backbone and the serum stability of the cyclized peptide was examined. The cyclic TxID peptide remained intact about 50% in human serum after 24 hours.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"1 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41385874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：