The aim of this paper is to explore the major issues involved in introducing sustainability concepts into university curricula in an interdisciplinary manner, through Systems Thinking. It is generally accepted that a ...The aim of this paper is to explore the major issues involved in introducing sustainability concepts into university curricula in an interdisciplinary manner, through Systems Thinking. It is generally accepted that a holistic approach is essential in sustainability studies, but teaching such a new and complex topic to a diverse student population is by no means easy. In this study, sustainability is viewed in the context of Systems Thinking, particularly in Complexity Management domain. A general framework is proposed with the intension of guiding potential instructors who are planning to teach sustainability through Systems Thinking. The framework includes only the suggested systems-oriented material and a review of some system methodologies; it does not cover sustainability issues. Methodologies known as System Dynamics and Soft Cybernetics are explored and emphasized particularly in the paper due to their importance. The framework is kept general enough so that it appeals to students and instructors with a variety of background.展开更多
BACKGROUND The purpose of the present study was to examine retrospectively the contribution of 18Fluorodeoxyglucose positron emission tomography computed tomography(18FDG-PET/CT)to the evaluation of response to first-...BACKGROUND The purpose of the present study was to examine retrospectively the contribution of 18Fluorodeoxyglucose positron emission tomography computed tomography(18FDG-PET/CT)to the evaluation of response to first-line gemcitabine plus cispla-tin-based chemotherapy in patients with metastatic bladder cancer.AIM To evaluate the response to Gemcitabine plus Cisplatin-based chemotherapy using 18FDG-PET/CT imaging in patients with metastatic bladder cancer.METHODS Between July 2007 and April 2019,79 patients underwent 18FDG-PET/CT imaging with the diagnosis of Metastatic Bladder Carcinoma(M-BCa).A total of 42 pa-tients(38 male,4 female)were included in the study,and all had been admi-nistered Gemcitabine plus Cisplatin-based chemotherapy.After completion of the therapy,the patients underwent a repeat 18FDG-PET/CT scan and the results were compared with the PET/CT findings before chemotherapy according to European Organisation for the Research and treatment of cancer criteria.Mean age was 66.1 years and standard deviation was 10.7 years(range:41–84 years).RESULTS Of the patients,seven(16.6%)were in complete remission,17(40.5%)were in partial remission,six(14.3%)had a stable disease,and 12(28.6%)had a pro-gressive disease.The overall response rate was 57.1 percent.CONCLUSION 18FDG-PET/CT can be considered as a successful imaging tool in evaluating response to first-line chemotherapy for metastatic bladder cancer.Anatomical and functional data obtained from PET/CT scans may be useful in the planning of secondline and thirdline chemotherapy.展开更多
Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniq...Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniques have been frequently implemented in this area,the existing studies disregard to the nat-ural order between the target attribute values of the historical sensor data.Thus,these methods cause losing the inherent order of the data that positively affects the prediction performances.To deal with this problem,a novel approach,named Ordinal Multi-dimensional Classification(OMDC),is proposed for estimating the conditions of a hydraulic system's four components by taking into the natural order of class values.To demonstrate the prediction ability of the proposed approach,eleven different multi-dimensional classification algorithms(traditional Binary Relevance(BR),Classifier Chain(CC),Bayesian Classifier Chain(BCC),Monte Carlo Classifier Chain(MCC),Probabilistic Classifier Chain(PCC),Clas-sifier Dependency Network(CDN),Classifier Trellis(CT),Classifier Dependency Trellis(CDT),Label Powerset(LP),Pruned Sets(PS),and Random k-Labelsets(RAKEL))were implemented using the Ordinal Class Classifier(OCC)algorithm.Besides,seven different classification algorithms(Multilayer Perceptron(MLP),Support Vector Machine(SVM),k-Nearest Neighbour(kNN),Decision Tree(C4.5),Bagging,Random Forest(RF),and Adaptive Boosting(AdaBoost))were chosen as base learners for the OCC algorithm.The experimental results present that the proposed OMDC approach using binary relevance multi-dimensional classification methods predicts the conditions of a hydraulic system's multiple components with high accuracy.Also,it is clearly seen from the results that the OMDC models that utilize ensemble-based classification algorithms give more reliable prediction performances with an average Hamming score of 0.853 than the others that use traditional algorithms as base learners.展开更多
This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool...This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool holders made from different materials,including Al 5083,Al 6082,Al 7012,and a standard 4140 material,were subjected to chatter vibration to investigate their process damping capabilities.The study found that the standard tool holder 4140 allows for higher stable depths of cut and produces similar process damping values compared to the other tool holders.Finite element analyses(FEA)were performed to verify the experimental results,and the modal and FEA analyses produced very similar results.The study concludes that future research should investigate the effects of tool holders made from high alloy steel alloys on process damping.Overall,this paper provides important insights into the effects of tool hold-er materials on chatter vibration and process damping in turning operations,which can help in the design of more effi-cient and effective cutting systems.展开更多
·AIM: To investigate the retinal nerve fiber layer(RNFL)thickness changes in patients with obstructive sleep apnea syndrome(OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glauco...·AIM: To investigate the retinal nerve fiber layer(RNFL)thickness changes in patients with obstructive sleep apnea syndrome(OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glaucoma in this population by using spectral domain optical coherence tomography(3D-OCT-2000 Spectral domain).·METHODS: After polysomnographic study, all subjects(64 OSAS patients and 40 controls) underwent detailed ophthalmological examination. After these examinations,patients with glaucoma and patients who had ophthalmological and/or systemic disease were excluded from the study.Totally, 20 patients in OSAS group and five patients in controls were excluded from the study in the first examination and follow-up period. The RNFL thickness was assessed with OCT. Forty-four OSAS patients and 35 control subjects were followed up for12 mo. RNFL thickness change and OSAS patients were evaluated for severity of disease by Apnea-Hypopnea Index(AHI).·RESULTS: Forty-four OSAS patients and 35 controls were enrolled in the study. Statistically significance was found between OSAS patients and controls at the 12 thmo.Average RNFL thickness was found to be significantly lower in last measurements in OSAS patients when compared with first measurements and control subjects(P 【0.001, 0.002, respectively). There was a statistically significant correlation among AHI, and RNFL thickness(P 【0.05).·CONCLUSION: The results suggest that the patients with OSAS were related with a proportional decrease in the RNFL thickness. These patients should be followed up regularly for glaucomatous changes. Detecting more RNFL thinning in severe OSAS was important.展开更多
AIM: To compare the efficacies of subconjunctival bevacizumab, ranibizumab, and pegaptanib sodium injections for the inhibition of corneal neovascularization in an experimental rat model. METHODS: Sixteen corneas of 1...AIM: To compare the efficacies of subconjunctival bevacizumab, ranibizumab, and pegaptanib sodium injections for the inhibition of corneal neovascularization in an experimental rat model. METHODS: Sixteen corneas of 16 rats were chemically cauterized and randomized into four groups: bevacizumab group that treated with 0.05mL/1.25mg bevacizumab, ranibizumab group that treated with 0.05mL/0.5mg ranibizumab, pegaptanib group that treated with 0.05mL/0.15mg pegaptanib sodium, and control group that treated with 0.05mL saline solution. Digital photographs of the corneas were taken and analyzed using an image analysis software program. All corneas were excised and examined histologically on the 15 th day. RESULTS: Each treatment group had significantly less neovascularized corneal areas and fewer blood vessels than the control group (all P 【0.05). In addition, bevacizumab group had significantly less neovascu-larized corneal areas and fewer blood vessels than ranibizumab and pegaptanib groups (both P 【0.05). However, there was no significant difference between the ranibizumab and pegaptanib groups regarding percentage of neovascularized corneal areas and number of blood vessels (both P 】0.05). CONCLUSION: Subconjunctival bevacizumab, ranibiz-umab, and pegaptanib sodium were effective with no corneal epitheliopathy for inhibiting corneal neovascularization after corneal burn in rats .Bevacizumab was more effective than ranibizumab and pegaptanib sodium.展开更多
AIM:To compare noncycloplegic and cycloplegic results of Retinomax measurements with findings achieved after cycloplegia using table-top autorefractor and retinoscopy.METHODS:The study included 127 patients(mean age96...AIM:To compare noncycloplegic and cycloplegic results of Retinomax measurements with findings achieved after cycloplegia using table-top autorefractor and retinoscopy.METHODS:The study included 127 patients(mean age96.7mo,range 21 to 221).Retinomax(Rmax)(Nikon Inc.,Japan)was used to obtain noncycloplegic refraction.Under cycloplegia,refraction was measured with Rmax,table-top autorefractor(TTR)(Nikon NRK 8000,Inc.,Japan)and retinoscopy.The values of sphere,spherical equivalent,cylinder and axis of cylinder were recorded for Rmax,TTR and retinoscopy in each eye.All results were analyzed statistically.RESULTS:The mean spheric values(SV),spherical equivalent values(SEV)and cylindrical values(CV)of the noncycloplegic Rmax(SV:0.64 D,SEV:0.65 D and CV:0.03 D,respectively)were found to be significantly lower than cycloplegic TTR(1.43 D,1.38 D and 0.3 D;P=0.012,P=0.011 and P=0.04,respectively)and retinoscopy(1.34 D,1.45 D and 0.23 D;P=0.04,P=0.002 and P=0.045,respectively).Mean cycloplegic SV,SEV,CV were not significantly different between Rmax and TTR,Rmax and retinoscopy,TTR and retinoscopy.Cycloplegic or noncycloplegic axis values were not different between any method.CONCLUSION:Rmax may be used successfully as a screening tool but may not be accurate enough for actual spectacle prescription.Cycloplegic Rmax measurements may be able to identify refractive error in children because of approximate results to retinoscopy.展开更多
The incidence of stone disease has been increasing and the risk of recurrent stone formation is high in a pediatric population. It is crucial to use the most effective method with the primary goal of complete stone re...The incidence of stone disease has been increasing and the risk of recurrent stone formation is high in a pediatric population. It is crucial to use the most effective method with the primary goal of complete stone removal to prevent recurrence from residual fragments. While extracorporeal shock wave lithotripsy(ESWL) is still considered first line therapy in many clinics for urinary tract stones in children, endoscopic techniques are widely preferred due to miniaturization of instruments and evolution of surgical techniques. The standard procedures to treat urinary stone disease in children are the same as those used in an adult population. These include ESWL, ureterorenoscopy, percutaneous nephrolithotomy(standard PCNL or mini-perc), laparoscopic and open surgery. ESWL is currently the procedure of choice for treating most upper urinary tract calculi in a pediatric population. In recent years, endourological management of pediatric urinary stone disease is preferred in many centers with increasing experience in endourological techniques and decreasing sizes of surgical equipment. The management of pediatric stone disease has evolved with improvements in the technique and a decrease in the size of surgical instru-ments. Recently, endoscopic methods have been safely and effectively used in children with minor complications. In this review, we aim to summarize the recent management of urolithiasis in children.展开更多
AIM:To assess the effect of topical bevacizumab use on postoperative pterygium recurrence in eyes who underwent pterygium excision with limbal-conjunctival autograft transplantation(LCAT).METHODS:eighty-eight eyes of ...AIM:To assess the effect of topical bevacizumab use on postoperative pterygium recurrence in eyes who underwent pterygium excision with limbal-conjunctival autograft transplantation(LCAT).METHODS:eighty-eight eyes of 88 patients with primary pterygium were included.Pterygia were graded preoperatively from type 1 to type 3(type 1 atrophic,type3 inflamed)according to the inflammatory status.The eyes were preoperatively randomized to receive topical steroid and antibiotic treatment(group 1,46 eyes)and additional topical bevacizumab(5 mg/mL;group 2,42eyes)in the postoperative period.All eyes underwent pterygium excision and LCAT.Medications were tapered and discontinued at one month.Postoperative complications and recurrence rates were recorded.RESULTS:The mean follow-up duration was 29.3±4.2mo(24-52mo)and 28.5±3.4(24-48mo)in group 1 and2,respectively(P】0.05).There were no statistically significant differences regarding the age or gender between groups(P】0.05).Also,the difference between groups with respect to pterygium type was not significant.During the follow-up period,recurrence developed in 2 eyes(4.3%)in group 1,whereas in one eye(2.4%)in group 2.No statistically significant difference between groups was found in recurrence rates(P】0.05).No re-operation for recurrence was necessary during the follow-up period in both groups.CONCLUSION:Topical bevacizumab seems to have no additonal effect on pterygium recurrence after LCAT.展开更多
INTRODUCTIONVasospastic angina （VSA） cardiac disorder that leads is an important functional to transient myocardial ischemia and is caused by sudden, intense and reversible coronary artery spasm resulting in subtota...INTRODUCTIONVasospastic angina （VSA） cardiac disorder that leads is an important functional to transient myocardial ischemia and is caused by sudden, intense and reversible coronary artery spasm resulting in subtotal or total occlusion.展开更多
AIM: To investigate the macular changes in eyes filled with silicone oil(SO) and course of these changes after SO removal. METHODS: A retrospective optical coherence tomography scan review was conducted for twenty-fou...AIM: To investigate the macular changes in eyes filled with silicone oil(SO) and course of these changes after SO removal. METHODS: A retrospective optical coherence tomography scan review was conducted for twenty-four patients who underwent uncomplicated pars plana vitrectomy with SO tamponade for complex retinal detachments were detected with optical coherence tomography before, and one week, one month and three months after SO removal.RESULTS: Mean duration of SO tamponade was 3.6±1.0mo(range 3-7mo). Cystoid macular edema(CME) was detected in 3 eyes before SO removal. Submacular fluid was represented in 1 eye before silicone SO removal.Resolution of CME and submacular fluid was achieved1 mo after SO removal in all eyes. Mean best corrected visual acuity(BCVA) was 1.15 ±0.65(range, hand movement to 0.2) before SO removal in the eyes without macular changes. After SO removal, the mean BCVA values at 1wk and 1 and 3mo, and 0.82 ±0.23, 0.76 ±0.21,and 0.70 ±0.19, all of which were significantly better than baseline(P =0.030, 0.017, 0.006 respectively). In the eyes with macular CME and subretinal fluid the mean BCVA was significantly improved at 3mo after SO removal compared with baseline(P =0.037).CONCLUSION: Decreased visual acuity in eyes filled with SO could be caused by macular complications due to SO. CME and subretinal fluid may resolve without any additional macular surgery after SO removal.展开更多
Gender stereotypes are descriptive beliefs about how males and females actually differ. Occupational gender stereotyping labels males and females performing an occupation in the context of gender stereotypes. Therefor...Gender stereotypes are descriptive beliefs about how males and females actually differ. Occupational gender stereotyping labels males and females performing an occupation in the context of gender stereotypes. Therefore, occupational gender stereotyping may serve as one of the barriers in women＇s career advancement. Within this framework, this study aims to examine the occupational gender stereotyping in the accounting profession in Turkey. Based on a survey conducted with business students, the perceived gender of the accounting profession is studied. In addition, a visual study is used to define occupational accounting stereotypes. Overall it is found that there is a significant difference between the stereotypes of male and female accountants＇ in Turkey, where the profession is （largely, overwhelmingly） male dominated.展开更多
Background: Discharge due to superficial wound infection and sternal dehiscence are the common complications of median sternotomy. This condition leads to mediastinitis. Mediastinitis is a serious condition which incr...Background: Discharge due to superficial wound infection and sternal dehiscence are the common complications of median sternotomy. This condition leads to mediastinitis. Mediastinitis is a serious condition which increases morbidity, mortality and hospital costs. The correct time for surgical treatment is contraversial in cases who have sternal dehiscence and discharge due to superficial infection. In this study, patients received sternal stabilization as soon as a diagnosis was made and monitored for the development of mediastinitis. Methods: Among the 1440 patients who had undergone elective CABG, a total of 85 patients who developed sternal dehiscence and superficial wound discharge were included in this study. These patients were re-operated on as soon as diagnosed and early sternal stabilization was provided. Results: The ratio of overall dehiscence was 5.9%. Mediastinitis developed in only 2 of the 85 patients. These patients were treated with VAC (Vacuum Assisted Closure) therapy. The ratio of overall mediastinitis was 0.13. Mediastinitis-related mortality was not detected. Conclusion: The ratio of mediastinitis decreases when patients who have discharge due to sternal dehiscence and superficial wound infection are immediately reviewed without waiting for the results of conventional methods such as antibiotic treatment and chest binder support.展开更多
AIM To comparatively evaluate Seldinger and Trocar techniques in the percutaneous treatment of hydatid disease. METHODS Trocar and Seldinger techniques were used for 49 and 56 cysts, respectively, among 106 hydatid cy...AIM To comparatively evaluate Seldinger and Trocar techniques in the percutaneous treatment of hydatid disease. METHODS Trocar and Seldinger techniques were used for 49 and 56 cysts, respectively, among 106 hydatid cysts in 88 patients. The number of males and females were 22 and 66, respectively with a mean age of 44.9 years(range, 15-87). Follow-up studies included cyst diameter, cyst contents, and morphological changes inthe cyst wall, local recurrence, and secondary invasion, using ultrasound, computerized tomography and chest X-rays. RESULTS The positive criteria of healing were a decrease in cyst diameter, progressive solidification of the cyst contents, and disappearance of the cyst. Local recurrence was defined as an increase in the cyst diameter and contents, and appearance of daughter cysts in the primary cavity, while secondary dissemination was defined as the appearance of new cysts outside the treated cyst. Mean duration of follow-up was 19.23 mo(range, 18-26 mo). Follow-up results demonstrated that no significant differences were present between the Trocar and Seldinger techniques in the percentage of decrease in the cyst volume, rate of early complications, local recurrence and secondary dissemination(P = 0.384, 0.069, 0.215 and 0.533, respectively). CONCLUSION There are no differences between the Seldinger and Trocar techniques that gain entry to the cyst cavity in terms of the efficacy of the treatment and the rates of early and late complications.展开更多
AIM: To investigate the efficacy of a novel intraoperative diagnostic technique for patients with preliminary diagnosis of autoimmune pancreatitis(AIP).METHODS: Patients with pancreatic surgery were reviewed to identi...AIM: To investigate the efficacy of a novel intraoperative diagnostic technique for patients with preliminary diagnosis of autoimmune pancreatitis(AIP).METHODS: Patients with pancreatic surgery were reviewed to identify those who received a preliminary diagnosis of AIP between January 2010 and January 2014. The following data were collected prospectively for patients with a pathological diagnosis of AIP: clinical and demographic features, radiological and operative findings, treatment procedure, and intraoperative capillary refill time(CRT) in the pancreatic bed.RESULTS: Eight patients(six males, two females; mean age: 51.4 years) met the eligibility criteria of pathologically confirmed diagnosis. The most frequent presenting symptoms were epigastric pain and weight loss. The most commonly conducted preoperative imaging studies were computed tomography and endoscopic retrograde pancreaticodoudenography. The most common intraoperative macroscopic observations were mass formation in the pancreatic head and diffuse hypervascularization in the pancreatic bed. All patients showed decreased CRT(median value: 0.76 s, range: 0.58-1.35). One-half of the patients underwent surgical resection and the other half received medical treatment without any further surgical intervention. CONCLUSION: This preliminary study demonstrates a novel experience with measurement of CRT in the pancreatic bed during the intraoperative evaluation of patients with AIP.展开更多
Surgical treatment of the complications associated with Meckel’s diverticulum is widely accepted, but surgical management of an asymptomatic diverticulum found incidentally during laparotomy for other reasons is cont...Surgical treatment of the complications associated with Meckel’s diverticulum is widely accepted, but surgical management of an asymptomatic diverticulum found incidentally during laparotomy for other reasons is controversial. Appendectomy is the most common reason for laparotomy in many pediatric surgery clinics. The most common causes of an intestinal obstruction in the early period after appendectomy are an intra-abdominal abscess, adhesive small bowel obstruction and invagination. Obstruction due to Meckel’s diverticulum is reported rarely. In this study, we present 2 cases, five and eleven years old, with an asymptomatic Meckel’s diverticulum where appendectomy was performed due to acute and perforated appendicitis and obstruction developed due to Meckel’s diverticulitis in the postoperative early stage. Meckel’s diverticulitis must be considered in intestinal obstruction cases developing in the early stages after appendectomy although quite rare.展开更多
The contagion of financial crises surrounding the markets around the world has been in the forefront of academic and public discussions. In this paper, we attempt to study the “contagion effect” of the stock market ...The contagion of financial crises surrounding the markets around the world has been in the forefront of academic and public discussions. In this paper, we attempt to study the “contagion effect” of the stock market crises around the world by studying the correlations of global stock returns and volatility. We analyze the daily returns of major stock indexes around the world to discover the timing and path of the transmission of shocks that manifest themselves in stock market returns. We construct VARs of major stock market index returns and volatilities. Our work differs from the literature in analyzing spillover effects between emerging markets and other major stock markets.展开更多
According to Michael Porter＇s Diamond Model, a business cluster is defined as geographic concentration of inter-connected companies and institutions working in a common industry. In addition, clusters encompass an ar...According to Michael Porter＇s Diamond Model, a business cluster is defined as geographic concentration of inter-connected companies and institutions working in a common industry. In addition, clusters encompass an array of collaborating and competing services and providers that create a specialized infrastructure, which supports the cluster＇s industry. The economic cluster model, represents a synergy, a dynamic relationship and a network between not only the companies that comprise a cluster but also the successful partnering of the stakeholders. Today in all over the world, successful clusters have established a greater competitive advantage and wealth creation for their regions when compared to companies not in a cluster. Given this success more policy makers and regions are considering fostering cluster development as building blocks of regional economies. Research is planned and performed for understanding the clustering in SMEs （small and medium enterprises） industrial estate in Istanbul if it gives a competitive advantage to the cluster members or not. It is performed to determine and satisfy the lack of knowledge about the small and medium enterprises＇ issues, technologic systems, production quality standards, capacity usage ratios, interactions with other firms, habits of following the technologic improvements and clustering effects on the members.展开更多
文摘The aim of this paper is to explore the major issues involved in introducing sustainability concepts into university curricula in an interdisciplinary manner, through Systems Thinking. It is generally accepted that a holistic approach is essential in sustainability studies, but teaching such a new and complex topic to a diverse student population is by no means easy. In this study, sustainability is viewed in the context of Systems Thinking, particularly in Complexity Management domain. A general framework is proposed with the intension of guiding potential instructors who are planning to teach sustainability through Systems Thinking. The framework includes only the suggested systems-oriented material and a review of some system methodologies; it does not cover sustainability issues. Methodologies known as System Dynamics and Soft Cybernetics are explored and emphasized particularly in the paper due to their importance. The framework is kept general enough so that it appeals to students and instructors with a variety of background.
文摘BACKGROUND The purpose of the present study was to examine retrospectively the contribution of 18Fluorodeoxyglucose positron emission tomography computed tomography(18FDG-PET/CT)to the evaluation of response to first-line gemcitabine plus cispla-tin-based chemotherapy in patients with metastatic bladder cancer.AIM To evaluate the response to Gemcitabine plus Cisplatin-based chemotherapy using 18FDG-PET/CT imaging in patients with metastatic bladder cancer.METHODS Between July 2007 and April 2019,79 patients underwent 18FDG-PET/CT imaging with the diagnosis of Metastatic Bladder Carcinoma(M-BCa).A total of 42 pa-tients(38 male,4 female)were included in the study,and all had been admi-nistered Gemcitabine plus Cisplatin-based chemotherapy.After completion of the therapy,the patients underwent a repeat 18FDG-PET/CT scan and the results were compared with the PET/CT findings before chemotherapy according to European Organisation for the Research and treatment of cancer criteria.Mean age was 66.1 years and standard deviation was 10.7 years(range:41–84 years).RESULTS Of the patients,seven(16.6%)were in complete remission,17(40.5%)were in partial remission,six(14.3%)had a stable disease,and 12(28.6%)had a pro-gressive disease.The overall response rate was 57.1 percent.CONCLUSION 18FDG-PET/CT can be considered as a successful imaging tool in evaluating response to first-line chemotherapy for metastatic bladder cancer.Anatomical and functional data obtained from PET/CT scans may be useful in the planning of secondline and thirdline chemotherapy.
文摘Predictive Maintenance is a type of condition-based maintenance that assesses the equipment's states and estimates its failure probability and when maintenance should be performed.Although machine learning techniques have been frequently implemented in this area,the existing studies disregard to the nat-ural order between the target attribute values of the historical sensor data.Thus,these methods cause losing the inherent order of the data that positively affects the prediction performances.To deal with this problem,a novel approach,named Ordinal Multi-dimensional Classification(OMDC),is proposed for estimating the conditions of a hydraulic system's four components by taking into the natural order of class values.To demonstrate the prediction ability of the proposed approach,eleven different multi-dimensional classification algorithms(traditional Binary Relevance(BR),Classifier Chain(CC),Bayesian Classifier Chain(BCC),Monte Carlo Classifier Chain(MCC),Probabilistic Classifier Chain(PCC),Clas-sifier Dependency Network(CDN),Classifier Trellis(CT),Classifier Dependency Trellis(CDT),Label Powerset(LP),Pruned Sets(PS),and Random k-Labelsets(RAKEL))were implemented using the Ordinal Class Classifier(OCC)algorithm.Besides,seven different classification algorithms(Multilayer Perceptron(MLP),Support Vector Machine(SVM),k-Nearest Neighbour(kNN),Decision Tree(C4.5),Bagging,Random Forest(RF),and Adaptive Boosting(AdaBoost))were chosen as base learners for the OCC algorithm.The experimental results present that the proposed OMDC approach using binary relevance multi-dimensional classification methods predicts the conditions of a hydraulic system's multiple components with high accuracy.Also,it is clearly seen from the results that the OMDC models that utilize ensemble-based classification algorithms give more reliable prediction performances with an average Hamming score of 0.853 than the others that use traditional algorithms as base learners.
基金This study was supported by the Scientific Research Coordination Unit of Pamukkale University under the project number 2011BSP020.
文摘This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool holders made from different materials,including Al 5083,Al 6082,Al 7012,and a standard 4140 material,were subjected to chatter vibration to investigate their process damping capabilities.The study found that the standard tool holder 4140 allows for higher stable depths of cut and produces similar process damping values compared to the other tool holders.Finite element analyses(FEA)were performed to verify the experimental results,and the modal and FEA analyses produced very similar results.The study concludes that future research should investigate the effects of tool holders made from high alloy steel alloys on process damping.Overall,this paper provides important insights into the effects of tool hold-er materials on chatter vibration and process damping in turning operations,which can help in the design of more effi-cient and effective cutting systems.
文摘·AIM: To investigate the retinal nerve fiber layer(RNFL)thickness changes in patients with obstructive sleep apnea syndrome(OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glaucoma in this population by using spectral domain optical coherence tomography(3D-OCT-2000 Spectral domain).·METHODS: After polysomnographic study, all subjects(64 OSAS patients and 40 controls) underwent detailed ophthalmological examination. After these examinations,patients with glaucoma and patients who had ophthalmological and/or systemic disease were excluded from the study.Totally, 20 patients in OSAS group and five patients in controls were excluded from the study in the first examination and follow-up period. The RNFL thickness was assessed with OCT. Forty-four OSAS patients and 35 control subjects were followed up for12 mo. RNFL thickness change and OSAS patients were evaluated for severity of disease by Apnea-Hypopnea Index(AHI).·RESULTS: Forty-four OSAS patients and 35 controls were enrolled in the study. Statistically significance was found between OSAS patients and controls at the 12 thmo.Average RNFL thickness was found to be significantly lower in last measurements in OSAS patients when compared with first measurements and control subjects(P 【0.001, 0.002, respectively). There was a statistically significant correlation among AHI, and RNFL thickness(P 【0.05).·CONCLUSION: The results suggest that the patients with OSAS were related with a proportional decrease in the RNFL thickness. These patients should be followed up regularly for glaucomatous changes. Detecting more RNFL thinning in severe OSAS was important.
文摘AIM: To compare the efficacies of subconjunctival bevacizumab, ranibizumab, and pegaptanib sodium injections for the inhibition of corneal neovascularization in an experimental rat model. METHODS: Sixteen corneas of 16 rats were chemically cauterized and randomized into four groups: bevacizumab group that treated with 0.05mL/1.25mg bevacizumab, ranibizumab group that treated with 0.05mL/0.5mg ranibizumab, pegaptanib group that treated with 0.05mL/0.15mg pegaptanib sodium, and control group that treated with 0.05mL saline solution. Digital photographs of the corneas were taken and analyzed using an image analysis software program. All corneas were excised and examined histologically on the 15 th day. RESULTS: Each treatment group had significantly less neovascularized corneal areas and fewer blood vessels than the control group (all P 【0.05). In addition, bevacizumab group had significantly less neovascu-larized corneal areas and fewer blood vessels than ranibizumab and pegaptanib groups (both P 【0.05). However, there was no significant difference between the ranibizumab and pegaptanib groups regarding percentage of neovascularized corneal areas and number of blood vessels (both P 】0.05). CONCLUSION: Subconjunctival bevacizumab, ranibiz-umab, and pegaptanib sodium were effective with no corneal epitheliopathy for inhibiting corneal neovascularization after corneal burn in rats .Bevacizumab was more effective than ranibizumab and pegaptanib sodium.
文摘AIM:To compare noncycloplegic and cycloplegic results of Retinomax measurements with findings achieved after cycloplegia using table-top autorefractor and retinoscopy.METHODS:The study included 127 patients(mean age96.7mo,range 21 to 221).Retinomax(Rmax)(Nikon Inc.,Japan)was used to obtain noncycloplegic refraction.Under cycloplegia,refraction was measured with Rmax,table-top autorefractor(TTR)(Nikon NRK 8000,Inc.,Japan)and retinoscopy.The values of sphere,spherical equivalent,cylinder and axis of cylinder were recorded for Rmax,TTR and retinoscopy in each eye.All results were analyzed statistically.RESULTS:The mean spheric values(SV),spherical equivalent values(SEV)and cylindrical values(CV)of the noncycloplegic Rmax(SV:0.64 D,SEV:0.65 D and CV:0.03 D,respectively)were found to be significantly lower than cycloplegic TTR(1.43 D,1.38 D and 0.3 D;P=0.012,P=0.011 and P=0.04,respectively)and retinoscopy(1.34 D,1.45 D and 0.23 D;P=0.04,P=0.002 and P=0.045,respectively).Mean cycloplegic SV,SEV,CV were not significantly different between Rmax and TTR,Rmax and retinoscopy,TTR and retinoscopy.Cycloplegic or noncycloplegic axis values were not different between any method.CONCLUSION:Rmax may be used successfully as a screening tool but may not be accurate enough for actual spectacle prescription.Cycloplegic Rmax measurements may be able to identify refractive error in children because of approximate results to retinoscopy.
文摘The incidence of stone disease has been increasing and the risk of recurrent stone formation is high in a pediatric population. It is crucial to use the most effective method with the primary goal of complete stone removal to prevent recurrence from residual fragments. While extracorporeal shock wave lithotripsy(ESWL) is still considered first line therapy in many clinics for urinary tract stones in children, endoscopic techniques are widely preferred due to miniaturization of instruments and evolution of surgical techniques. The standard procedures to treat urinary stone disease in children are the same as those used in an adult population. These include ESWL, ureterorenoscopy, percutaneous nephrolithotomy(standard PCNL or mini-perc), laparoscopic and open surgery. ESWL is currently the procedure of choice for treating most upper urinary tract calculi in a pediatric population. In recent years, endourological management of pediatric urinary stone disease is preferred in many centers with increasing experience in endourological techniques and decreasing sizes of surgical equipment. The management of pediatric stone disease has evolved with improvements in the technique and a decrease in the size of surgical instru-ments. Recently, endoscopic methods have been safely and effectively used in children with minor complications. In this review, we aim to summarize the recent management of urolithiasis in children.
文摘AIM:To assess the effect of topical bevacizumab use on postoperative pterygium recurrence in eyes who underwent pterygium excision with limbal-conjunctival autograft transplantation(LCAT).METHODS:eighty-eight eyes of 88 patients with primary pterygium were included.Pterygia were graded preoperatively from type 1 to type 3(type 1 atrophic,type3 inflamed)according to the inflammatory status.The eyes were preoperatively randomized to receive topical steroid and antibiotic treatment(group 1,46 eyes)and additional topical bevacizumab(5 mg/mL;group 2,42eyes)in the postoperative period.All eyes underwent pterygium excision and LCAT.Medications were tapered and discontinued at one month.Postoperative complications and recurrence rates were recorded.RESULTS:The mean follow-up duration was 29.3±4.2mo(24-52mo)and 28.5±3.4(24-48mo)in group 1 and2,respectively(P】0.05).There were no statistically significant differences regarding the age or gender between groups(P】0.05).Also,the difference between groups with respect to pterygium type was not significant.During the follow-up period,recurrence developed in 2 eyes(4.3%)in group 1,whereas in one eye(2.4%)in group 2.No statistically significant difference between groups was found in recurrence rates(P】0.05).No re-operation for recurrence was necessary during the follow-up period in both groups.CONCLUSION:Topical bevacizumab seems to have no additonal effect on pterygium recurrence after LCAT.
文摘INTRODUCTIONVasospastic angina （VSA） cardiac disorder that leads is an important functional to transient myocardial ischemia and is caused by sudden, intense and reversible coronary artery spasm resulting in subtotal or total occlusion.
文摘AIM: To investigate the macular changes in eyes filled with silicone oil(SO) and course of these changes after SO removal. METHODS: A retrospective optical coherence tomography scan review was conducted for twenty-four patients who underwent uncomplicated pars plana vitrectomy with SO tamponade for complex retinal detachments were detected with optical coherence tomography before, and one week, one month and three months after SO removal.RESULTS: Mean duration of SO tamponade was 3.6±1.0mo(range 3-7mo). Cystoid macular edema(CME) was detected in 3 eyes before SO removal. Submacular fluid was represented in 1 eye before silicone SO removal.Resolution of CME and submacular fluid was achieved1 mo after SO removal in all eyes. Mean best corrected visual acuity(BCVA) was 1.15 ±0.65(range, hand movement to 0.2) before SO removal in the eyes without macular changes. After SO removal, the mean BCVA values at 1wk and 1 and 3mo, and 0.82 ±0.23, 0.76 ±0.21,and 0.70 ±0.19, all of which were significantly better than baseline(P =0.030, 0.017, 0.006 respectively). In the eyes with macular CME and subretinal fluid the mean BCVA was significantly improved at 3mo after SO removal compared with baseline(P =0.037).CONCLUSION: Decreased visual acuity in eyes filled with SO could be caused by macular complications due to SO. CME and subretinal fluid may resolve without any additional macular surgery after SO removal.
文摘Gender stereotypes are descriptive beliefs about how males and females actually differ. Occupational gender stereotyping labels males and females performing an occupation in the context of gender stereotypes. Therefore, occupational gender stereotyping may serve as one of the barriers in women＇s career advancement. Within this framework, this study aims to examine the occupational gender stereotyping in the accounting profession in Turkey. Based on a survey conducted with business students, the perceived gender of the accounting profession is studied. In addition, a visual study is used to define occupational accounting stereotypes. Overall it is found that there is a significant difference between the stereotypes of male and female accountants＇ in Turkey, where the profession is （largely, overwhelmingly） male dominated.
文摘Background: Discharge due to superficial wound infection and sternal dehiscence are the common complications of median sternotomy. This condition leads to mediastinitis. Mediastinitis is a serious condition which increases morbidity, mortality and hospital costs. The correct time for surgical treatment is contraversial in cases who have sternal dehiscence and discharge due to superficial infection. In this study, patients received sternal stabilization as soon as a diagnosis was made and monitored for the development of mediastinitis. Methods: Among the 1440 patients who had undergone elective CABG, a total of 85 patients who developed sternal dehiscence and superficial wound discharge were included in this study. These patients were re-operated on as soon as diagnosed and early sternal stabilization was provided. Results: The ratio of overall dehiscence was 5.9%. Mediastinitis developed in only 2 of the 85 patients. These patients were treated with VAC (Vacuum Assisted Closure) therapy. The ratio of overall mediastinitis was 0.13. Mediastinitis-related mortality was not detected. Conclusion: The ratio of mediastinitis decreases when patients who have discharge due to sternal dehiscence and superficial wound infection are immediately reviewed without waiting for the results of conventional methods such as antibiotic treatment and chest binder support.
文摘AIM To comparatively evaluate Seldinger and Trocar techniques in the percutaneous treatment of hydatid disease. METHODS Trocar and Seldinger techniques were used for 49 and 56 cysts, respectively, among 106 hydatid cysts in 88 patients. The number of males and females were 22 and 66, respectively with a mean age of 44.9 years(range, 15-87). Follow-up studies included cyst diameter, cyst contents, and morphological changes inthe cyst wall, local recurrence, and secondary invasion, using ultrasound, computerized tomography and chest X-rays. RESULTS The positive criteria of healing were a decrease in cyst diameter, progressive solidification of the cyst contents, and disappearance of the cyst. Local recurrence was defined as an increase in the cyst diameter and contents, and appearance of daughter cysts in the primary cavity, while secondary dissemination was defined as the appearance of new cysts outside the treated cyst. Mean duration of follow-up was 19.23 mo(range, 18-26 mo). Follow-up results demonstrated that no significant differences were present between the Trocar and Seldinger techniques in the percentage of decrease in the cyst volume, rate of early complications, local recurrence and secondary dissemination(P = 0.384, 0.069, 0.215 and 0.533, respectively). CONCLUSION There are no differences between the Seldinger and Trocar techniques that gain entry to the cyst cavity in terms of the efficacy of the treatment and the rates of early and late complications.
文摘AIM: To investigate the efficacy of a novel intraoperative diagnostic technique for patients with preliminary diagnosis of autoimmune pancreatitis(AIP).METHODS: Patients with pancreatic surgery were reviewed to identify those who received a preliminary diagnosis of AIP between January 2010 and January 2014. The following data were collected prospectively for patients with a pathological diagnosis of AIP: clinical and demographic features, radiological and operative findings, treatment procedure, and intraoperative capillary refill time(CRT) in the pancreatic bed.RESULTS: Eight patients(six males, two females; mean age: 51.4 years) met the eligibility criteria of pathologically confirmed diagnosis. The most frequent presenting symptoms were epigastric pain and weight loss. The most commonly conducted preoperative imaging studies were computed tomography and endoscopic retrograde pancreaticodoudenography. The most common intraoperative macroscopic observations were mass formation in the pancreatic head and diffuse hypervascularization in the pancreatic bed. All patients showed decreased CRT(median value: 0.76 s, range: 0.58-1.35). One-half of the patients underwent surgical resection and the other half received medical treatment without any further surgical intervention. CONCLUSION: This preliminary study demonstrates a novel experience with measurement of CRT in the pancreatic bed during the intraoperative evaluation of patients with AIP.
文摘Surgical treatment of the complications associated with Meckel’s diverticulum is widely accepted, but surgical management of an asymptomatic diverticulum found incidentally during laparotomy for other reasons is controversial. Appendectomy is the most common reason for laparotomy in many pediatric surgery clinics. The most common causes of an intestinal obstruction in the early period after appendectomy are an intra-abdominal abscess, adhesive small bowel obstruction and invagination. Obstruction due to Meckel’s diverticulum is reported rarely. In this study, we present 2 cases, five and eleven years old, with an asymptomatic Meckel’s diverticulum where appendectomy was performed due to acute and perforated appendicitis and obstruction developed due to Meckel’s diverticulitis in the postoperative early stage. Meckel’s diverticulitis must be considered in intestinal obstruction cases developing in the early stages after appendectomy although quite rare.
文摘The contagion of financial crises surrounding the markets around the world has been in the forefront of academic and public discussions. In this paper, we attempt to study the “contagion effect” of the stock market crises around the world by studying the correlations of global stock returns and volatility. We analyze the daily returns of major stock indexes around the world to discover the timing and path of the transmission of shocks that manifest themselves in stock market returns. We construct VARs of major stock market index returns and volatilities. Our work differs from the literature in analyzing spillover effects between emerging markets and other major stock markets.
文摘According to Michael Porter＇s Diamond Model, a business cluster is defined as geographic concentration of inter-connected companies and institutions working in a common industry. In addition, clusters encompass an array of collaborating and competing services and providers that create a specialized infrastructure, which supports the cluster＇s industry. The economic cluster model, represents a synergy, a dynamic relationship and a network between not only the companies that comprise a cluster but also the successful partnering of the stakeholders. Today in all over the world, successful clusters have established a greater competitive advantage and wealth creation for their regions when compared to companies not in a cluster. Given this success more policy makers and regions are considering fostering cluster development as building blocks of regional economies. Research is planned and performed for understanding the clustering in SMEs （small and medium enterprises） industrial estate in Istanbul if it gives a competitive advantage to the cluster members or not. It is performed to determine and satisfy the lack of knowledge about the small and medium enterprises＇ issues, technologic systems, production quality standards, capacity usage ratios, interactions with other firms, habits of following the technologic improvements and clustering effects on the members.
