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FRACTIONAL MACLAURIN-TYPE INEQUALITIES FOR TWICE-DIFFERENTIABLE FUNCTIONS
Get PDFWe prove an equality for twice-differentiable functions whose second derivatives in absolute value are convex. We use this, together with the H & ouml;lder and power-mean inequalities, to establish some Maclaurin-type inequalities for Riemann-Liouville fractional integrals. We conclude with some special cases
Investigation of different machine learning algorithm performances in the classification of Alzheimer's disease
Get PDFAlzheimer hastalığı, dünya genelinde milyonlarca bireyi etkileyen, ilerleyici ve geri dönüşü olmayan bir nörodejeneratif bozukluktur. Erken tanı, hastalığın ilerlemesini yavaşlatmak, tedavi yaklaşımlarını optimize etmek ve yaşam kalitesini korumak açısından büyük önem taşımaktadır. Bu tez çalışmasında, Alzheimer tanısı konmuş bireylerle sağlıklı kontrol grubuna ait EEG verileri analiz edilmiştir. EEG sinyallerinden dispersiyon entropisi yöntemiyle elde edilen öznitelikler temel alınarak, çeşitli makine öğrenmesi algoritmalarının sınıflandırma performansları karşılaştırılmıştır. Dispersiyon entropisi ve performans hesaplamaları MATLAB R2018a ortamında geliştirilen özel algoritmalar ile gerçekleştirilmiş ve elde edilen öznitelikler K-En Yakın Komşu, Karar Ağaçları ve Rastgele Ormanlar modellerine uygulanmıştır. Modellerin performansları; doğruluk, kesinlik, duyarlılık, F1 skoru ve ROC-AUC gibi metriklerle değerlendirilmiş, ayrıca her bir model için 10 katlı çapraz doğrulama ile genelleme yetenekleri test edilmiştir. Elde edilen bulgular, KNN algoritmasının hasta sınıfını ayırt etmekte yetersiz kaldığını ve sınıflar arasında rastgele ayırım yaptığını göstermiştir (AUC: 0.50). Buna karşın, Karar Ağaçları ve özellikle Rastgele Ormanlar algoritması daha dengeli bir sınıflandırma başarısı sunmuş; Rastgele Ormanlar modeli %75 genel doğruluk, %71 çapraz doğrulama başarısı ve 0.80 F1 skoru ile en başarılı sonuçları elde etmiştir. Ayrıca, dispersiyon entropisi analizi sonucunda Alzheimer hastalarının EEG sinyallerinde, özellikle oksipital başta olmak üzere parietal ve temporal bölgelerde entropi düzeylerinin anlamlı biçimde azaldığı tespit edilmiştir. Bu bulgular, DE'nin nörofizyolojik bozulmaları yansıtma kapasitesine sahip olduğunu ve Alzheimer hastalığının erken tanısında potansiyel bir EEG tabanlı biyobelirteç olarak kullanılabileceğini göstermektedir.Alzheimer's disease is a progressive and irreversible neurodegenerative disorder that affects millions of individuals worldwide. Early diagnosis plays a critical role in slowing disease progression, optimizing treatment approaches, and maintaining quality of life. In this thesis study, EEG data obtained from individuals diagnosed with Alzheimer's disease and healthy control subjects were analyzed. Features extracted from EEG signals using the dispersion entropy method were utilized to compare the classification performance of various machine learning algorithms. Dispersion entropy and performance calculations were conducted using custom algorithms developed in the MATLAB R2018a environment, and the extracted features were applied to K-Nearest Neighbors , Decision Tree , and Random Forest models. The performance of the models was evaluated using metrics such as accuracy, precision, recall, F1 score, and ROC-AUC, and the generalization ability of each model was tested through 10-fold cross-validation. The findings revealed that the KNN algorithm was insufficient in distinguishing the patient class and exhibited random classification between classes (AUC: 0.50). In contrast, the Decision Tree and especially the Random Forest algorithm demonstrated more balanced classification performance; the Random Forest model achieved the highest results with 75% overall accuracy, 71% cross-validation accuracy, and an F1 score of 0.80. Furthermore, the dispersion entropy analysis indicated that entropy levels in the EEG signals of Alzheimer's patients were significantly reduced, particularly in the occipital, as well as parietal and temporal regions. These findings suggest that DE is capable of reflecting neurophysiological impairments and may serve as a potential EEG-based biomarker for the early diagnosis of Alzheimer's disease
A rare case of subclavian steal phenomenon with anterograde vertebral artery flow
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Effect of Cryogenic Process on Trametes versicolor and Fomitopsis palustris Fungal Destruction in ThermoWood® Products of Some Wood Species
Get PDFAspen, ash, spruce, and fir trees naturally grown in Turkey were obtained directly from the forest and processed using ThermoWood (R)(TM) processing at two different temperatures (190 degrees C: TW1 and at 212 degrees C: TW2). Then, cryogenic treatment (Cr) was applied to the samples, and they were placed in a jar containing Trametes versicolor (COV) and Fomitopsis palustris (TYP) mushrooms. Their weight loss (WL) was measured after 12 weeks. Although WL results varied depending on the tree type and the applied processes, it has been understood that Cr application can be effective in reducing WL. According to the study, the lowest WL was determined to be in COV fungus with 1.2% in cryogenically treated fir tree TW2 samples. The highest WL was in TYP mushrooms with 56.1% in spruce TW1 samples that received heat treatment (HT). The results obtained from the study show that cryogenic treatment may be an alternative method for reducing WL in heat treated wood species
Can the combination index be used as a new perspective in characterizing the toxicity of metal mixtures?
Get PDFInvestigating the characterization of toxicity from new perspective requires considering the multiple interactions between different toxicants and moving beyond the traditional indices. Therefore, in this study, it is aimed to address these shortcomings by investigating the toxicological effects of nickel (Ni), cobalt (Co) and iron (Fe) both individually and in binary and ternary combinations by focusing on the inhibition of bioluminescence of Aliivibrio fischeri and Daphnia magna as the test organisms. The toxicity of the metals was categorized according to the index methods: Combination Index (CI), Toxicity Unit (TU), Mixture Toxicity Index (MTI) and modelling techniques: Concentration Addition (CA) and Independent Action (IA) models for prediction the EC50 values. Consequently, toxicity showed antagonistic effects at lower levels within the binary and ternary mixtures of Ni, Co, and Fe, while a synergistic toxicity was determined by the Ni-Co mixture, particularly at higher concentrations. These findings highlight that the CI can be used as a comprehensive tool to accurately assess chemical interactions in environmental toxicology. Particularly noteworthy is the effectiveness of the CI-isobologram equation as a suitable approach to assess the toxicological effects of metal interactions on A. fischeri
The Effect of Hygroscopic Wood Structure on Some Properties of Heat Treated Products Formed with the Thermowood Method
Get PDFChanges were determined for the values of physical and mechanical properties resulting from hygroscopicity in some wood species after heat treatment (HT), and to reveal statistically the relationships between the properties. For this purpose, aspen (Populus tremula) and fir (Abies nordmanniana subsp. bornmuelleriana) species were evaluated for weight loss (WL) during HT as well as water thickness swelling (WTS) and weight and volume change rates upon water imersion. The amounts and density values of longitudinal, radial, tangential, and volumetric contractions and expansions, static bending resistance (MOR) and static bending modulus of elasticity (MOE) were examined. From the results and correlation analysis, it was determined that while WL increased in all variations with HT, the WTS values from the HT samples in water for 24 h decreased with the increase in temperature and time, while water retention was at similar rates in all variations, including UT. At the same time, HT resulted in significant decreases in all density values and contraction and expansion values, and the dimensional stability improved. On the other hand, it was understood that HT did not negatively affect both MOR and MOE resistance values at the 180 degrees C and 200 degrees C conditions. These results showed that heat-treated wood products can be a good alternative to avoid problems caused by hygroscopicity under the influence of intense water contact
New (α, β)-order pre-Gruss fractional integral inequalities and applications for CRV
Get PDFIn this paper, we employ Riemann-Liouville fractional integrals to derive two primary integral findings concerning the alpha- pre-Gruss inequality and the (alpha, beta)- pre-Gruss inequality. Our results extend existing integral inequalities reported in the literature. Additionally, we discuss some applications of our results for continuous random variables (CRV, for short) with bounded probability density functions. Some new estimates are provided in this context, along with classical results obtained as special cases from our results
On the Fractional Inequalities of the Milne Type
Get PDFOur investigations in this paper revolve around exploring fractional variants of inequalities of Milne type by applying twice differentiable convex mappings. Based on some principles of convexity, H & ouml;lder inequality, and power-mean inequality, novel inequalities are derived. The acquired inequalities are supported by illustrative examples, which are calculated via their proofs. Additionally, graphical representations are to verify the examples visually. Furthermore, this investigation unveils fresh findings within the realm of inequalities
Catalytic combustion efficiency and emission reduction of amorphous boron/lanthanum orthoferrite nano-hybrids in hydrocarbon fuels
Get PDFThe effects of amorphous boron (AB) hybrid particles decorated with lanthanum orthoferrite particles on the combustion behavior and emission performance of conventional fuels were investigated. They are produced by combining ball-milling amorphous boron particles (AB/BM), Fe3O4 (F2) ferrite produced by sol-gel technique and La0.75Fe1.25O3 (LAF2) and LaFeO3 (LAF3) lanthanum ferrite nanoparticles by an ultrasonication technique. At 2.5 wt% (17353 ppm) particle load, the highest maximum flame temperature of gasoline-based nanofluid droplets was 644 K for AB-B.M., while at 7.5 wt% (52059 ppm) concentrations, the maximum aggregate temperatures were 642 K, 1358 K and 1298 K in the presence of nanohybrid structures based on AB-B.M., AB/LAF2 and AB/LAF3, respectively. At 2.5 wt% concentrations the lowest extinction time was recorded as 1321 ms for fuel droplets containing AB/LAF2 particles and at 7.5 wt% concentrations 1565 ms in the presence of AB-BM particles. According to the diesel engine test results, AB/LAF2 particulates have a 15 % and 17.6 % reduction in HRR compared to D100 at 15 Nm and 45 Nm respectively, and the largest reduction in BSFC values is 8.38 % and 7.99 % respectively at the same loads. At 60 Nm the highest decrease in CO emissions was 0.01 % in the presence of AB/LAF2 particles. The lowest HC emissions were observed in the presence of AB/LAF2 particulates, with 61.7 %, 42.85 %, 30.43 % and 41.37 % reduction in HC emissions compared to pure diesel at 15 Nm, 30 Nm, 45 Nm and 60 Nm respectively. At 30Nm, 45Nm and 60Nm, the lowest NOx emissions were recorded for the D100 + 250AB/LAF2 fuel, with reductions of 6.71 %, 9.33 % and 12.59 % respectively compared to D100
Bibliyoterapinin İlkokul Öğrencilerinin Sağlık Okuryazarlığı ve Acil Servis Farkındalıkları Üzerine Etkisi: Tek Gruplu Yarı Deneysel Çalışma
Get PDFAim: The aim of this study was to enhance primary school students' knowledge levels concerning health literacy and awareness of emergency department services through the use of bibliotherapy. Material and Methods: This study employed a pre-test and post-test, one-group quasi-experimental design. The study sample consisted of 62 fourth-grade primary school students. Data were collected using the "Personal Information Form", "Health Literacy Scale for School-Age Children", and "Structured Questions on Emergency Service Awareness". A paired samples t-test was used to compare the dependent groups. The relationship between dependent categorical variables was examined using the McNemar test. A significance level of 0.05 was used as the criterion for interpreting whether the obtained values were statistically significant. Results: A statistically significant difference was found between the pre-test and post-test scores of primary school students regarding their knowledge levels related to emergency department awareness (t61= -2.29; p<0.05). The increase in students' knowledge about triage colors in the emergency department and their understanding of the concept of triage was also statistically significant following bibliotherapy intervention (p<0.05). The improvement in knowledge regarding appropriate situations for emergency department visits was also found to be statistically significant (p<0.05). However, bibliotherapy was not found to have a statistically significant effect on the health literacy levels of primary school students, as there was no significant difference between their pre-test and post-test scores (p>0.05). Conclusion: It was concluded that bibliotherapy was effective in increasing primary school students' knowledge about the appropriate use of emergency services. In line with the topics covered in the bibliotherapy text, students were found to have learned the emergency department triage color codes, understood the concept of triage, and improved their knowledge of situations that require emergency care. These findings suggest that bibliotherapy-based course content can be developed to raise awareness among children—beginning from primary education—regarding the appropriate and effective use of healthcare services. Such initiatives should be supported by a multidisciplinary approach that integrates emergency medicine, psychiatric nursing, and educational sciences.Amaç: Bu çalışmada bibliyoterapi ile ilkokul öğrencilerinin sağlık okuryazarlığı ve acil servis farkındalıklarına yönelik bilgi düzeylerini geliştirmek amaçlanmıştır. Gereç ve Yöntemler: Bu araştırma, ön test ve son test, tek grup yarı deneysel desende yürütülmüştür. Araştırmanın örneklemini 4. sınıfa giden 62 ilkokul öğrencisi oluşturmaktadır. Araştırmanın verileri "Kişisel Bilgi Formu", "Okul Çağındaki Çocuklar için Sağlık Okuryazarlığı Ölçeği" ve "Acil Servis Farkındalığına Yönelik Yapılandırılmış Sorular" ile toplanmıştır. Bağımlı iki grup karşılaştırmasında bağımlı örneklem t-testi kullanılmıştır. Bağımlı kategorik değişkenler arası ilişkiye McNemar testi ile bakılmıştır. Elde edilen değerlerin anlamlı olup olmadığının yorumlanmasında 0,05 anlamlılık düzeyi ölçüt olarak kullanılmıştır. Bulgular: Çalışmada yer alan ilkokul öğrencilerinin acil servis farkındalığına yönelik bilgi düzeyleri ön test ve son test puanları arasında istatistiksel olarak anlamlı bir fark tespit edildi (t61=-2,29; p<0,05). Bibliyoterapi sonrasında öğrencilerin acil serviste bulunan triaj renklerine ilişkin ve triajın ne olduğunu anlamalarına yönelik bilgi düzeylerindeki artışın anlamlı olduğu sonucuna ulaşıldı (p<0,05). Acil servise hangi durumlarda başvurulması gerektiğine ilişkin bilgi düzeylerindeki artışın da anlamlı olduğu saptandı (p<0,05). İlkokul öğrencilerinde bibliyoterapinin sağlık okuryazarlığı üzerinde ön test ve son test puanları arasında anlamlı bir etkisinin olmadığı sonucuna ulaşıldı (p>0,05). Sonuç: Bibliyoterapinin ilkokul öğrencilerinin acil servis kullanımına yönelik bilgi düzeylerini arttırmakta etkili olduğu sonucuna ulaşılmıştır. Bibliyoterapi metni içerisinde ele alınan konular doğrultusunda öğrencilerin acil serviste bulunan triaj renk kodlarını öğrendikleri, triaj uygulamasının ne olduğunu anladıkları ve acil servislere hangi durumlarda başvurulması gerektiğine yönelik bilgi düzeylerinin arttığı belirlenmiştir. Bu sonuçlar doğrultusunda, acil tıp, psikiyatri hemşireliği ve eğitim bilimlerinin multidisipliner yaklaşımı temel alınarak, ilköğretim düzeyinden itibaren çocuklara sağlık hizmeti sunan kurumların doğru ve etkili kullanımına yönelik farkındalık kazandırmayı amaçlayan, bibliyoterapi temelli ders içerikleri geliştirilebilir