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Conehead thyme (Thymbra capitata) is widely distributed in the countries of the Mediterranean region and used due to its medical properties. The antibacterial, antifungal, and strong antioxidant properties of T. capitata are known. The model organism Galleria mellonella is mostly preferred for immunological studies and for the study of human pathogens. The aim of the study was to determine the effect of the ethanolic extract of T. capitata on the antioxidant defense of the hemolymph in G. mellonella larva. Solutions prepared with Phosphate-Buffered Saline (PBS) from the dry matter obtained from ethanolic extract at doses between 2 mg mL-1 and 20 mg mL-1 were injected into G. mellonella larvae. According to our findings, T. capitata extract had no effect on malondialdehyde (MDA) levels. However, it was determined that all doses between 10 to 20 mg mL-1 significantly reduced superoxide dismutase (SOD) and catalase (CAT) activities compared to the control groups. According to the results of our study, high doses of T. capitata extract had negative effects on G. mellonella antioxidant defense.

These statistical data contain detailed statistical information of the study titled "The Impact of olive leaf extract on antioxidant enzyme activity in the hemolymph of Galleria mellonella".

“Demokrasi” kavramı üzerine tartışmalar yüzyıllardır sürmektedir. Kesin bir tanıma varılamamakla birlikte, eşitlik, özgürlük, halk egemenliği, çoğulculuk gibi belirli değerler demokrasi çerçevesinde benimsenmektedir. Bu değerleri benimsemek demokrasinin varlığı ve geleceği için gerekmektedir. Bu değerlerin kazanılmasının bir yolu da eğitimden geçmektedir ve bu çalışmanın yapılmasının asıl sebebi de tam bu noktada kendisine yer bulmaktadır. Çalışmada demokrasinin tanımı eğitim kavramıyla paralel şekilde ele alınarak Platon, Seymour Martin Lipset, Maurice Duverger gibi düşünürlerin demokrasi-eğitim bağlantısı üzerine söylemlerine ve fikirlerine yer verilmektedir. Bu yapılırken sadece Kıta Avrupası’nın düşünürlerinin sentezlerini incelemekle beraber, Amerika’da yapılmış olan araştırmalardan çıkan sonuçların bu ilişkiye dair sunmuş olduğu yorumlara da değinilmektedir. İkinci bölümde demokrasinin genel tanımı ile eğitimli bireyler ve toplumların demokratik süreçlere etkisi incelenmiştir. Üçüncü bölümde kimlerin yönetimde söz sahibi olması gerektiğini anlamak için eğitimli kişilerin yönetime etkisine değinilmiştir. Dördüncü bölümde ise eğitimin, demokratik yönetimler için yeterli yetiye sahip olup olmadığına ve nihayetinde demokrasiye vasıl olma noktasında eğitimin hem müspet hem olumsuz durumuna değinilmiştir.

SUMMARY OBJECTIVE: This study aimed to investigate the extension of labral tears associated with paraglenoid labral cysts by magnetic resonance arthrography. METHODS: The magnetic resonance and magnetic resonance arthrography images of patients with paraglenoid labral cysts who presented to our clinic between 2016 and 2018 were examined. In patients with paraglenoid labral cysts, the location of the cysts, the relation between the cyst and the labrum, the location and extent of glenoid labrum damage, and whether there was contrast medium passage into the cysts were investigated. The accuracy of magnetic resonance arthrographic information was evaluated in patients undergoing arthroscopy. RESULTS: In this prospective study, a paraglenoid labral cyst was detected in 20 patients. In 16 patients, there was a defect in the labrum adjacent to the cyst. Seven of these cysts were adjacent to the posterior superior labrum. In 13 patients, there were contrast solution leak into the cyst. For the remaining seven patients, no contrast-medium passage was observed in the cyst. Three patients had sublabral recess anomalies. Two patients had rotator cuff muscle denervation atrophy accompanying the cysts. The cysts of these patients were larger compared to those of the other patients. CONCLUSION: Paraglenoid labral cysts are frequently associated with the rupture of the adjacent labrum. In these patients, symptoms are generally accompanied by secondary labral pathologies. Magnetic resonance arthrography can be successfully used not only to demonstrate the association of the cyst with the joint capsule and labrum, but also to reliably demonstrate the presence and extension of labral defects.

Since the fruits and leaves of the Olive (Olea europea) tree, which grows naturally in Mediterranean countries, are thought to be beneficial for many diseases, it is widely used in folk medicine in these countries. Olive leaf extract has been used in the treatment of many diseases such as malaria, high fever, heart diseases and cancer. The greater wax moth Galleria mellonella (Lepidoptera: Pyralidae) is frequently used in invertebrate immunity studies due to its similarity to the mammalian natural immune system. Melanization occurs when quinone precursors are converted to melanin and inactive profenoloxidase to phenoloxidase enzyme. In this study, the phenoloxidase activity of G. mellonella hemolymph larvae injected with olive leaf extract in different doses was determined by ELISA microplate reader at 492 nm absorbance. The findings obtained from this study showed that olive leaf extract increased phenoloxidase activity at a dose of 0.001 mg mL-1. Lower doses of 0.001 mg mL-1 did not cause changes in phenoloxidase activity compared to the untreated and Dimethyl Sulfoxide (DMSO) groups. The highest olive leaf extract dose of our study is 0.01 mg mL-1 and the larvae did not survive for 24 hours over those doses. The results of our study show that olive leaf supports humoral immune responses when used in low doses.

Endoparasitoid species devoid of symbiotic viruses inject secretions derived from their reproductive glands into their hosts during parasitism in order to avoid various immune responses of their hosts. Pimpla turionellae L. (Hymenoptera: Ichneumonidae) is an endoparasitoid that lacks polydnaviruses, and its venom has previously been shown to paralyze the host Galleria mellonella (Lepidoptera: Pyralidae) and suppress its immune reactions to ensure the egg survival. The present study demonstrates that another female-injected factor calyx fluid extracted from the P. turionellae ovary is also responsible for the suppression of G. mellonella immunity. The total hemocyte counts of G. mellonella decrease after treatment with calyx fluid in a concentration-dependent manner. Significant reductions in cell viability are also observed at all calyx fluid doses both in vivo and in vitro. The analyses of the beads injected into the insects as encapsulation targets revealed that the number of encapsulated beads reduced significantly compared to controls post-calyx fluid injection. The injection of the highest calyx fluid dose (1 female equivalent calyx) is sufficient to completely inhibit the strong encapsulation and melanization reactions of the last instar larvae 24 h post-injection. These results demonstrate that P. turionellae calyx fluid is required to regulate host immunity for successful parasitization.

Immune responses play a key role in the survival of all living things. Intake of inorganic materials is of critical importance in living organisms because of their participation in metabolism and some component of cells. Iron (Fe), magnesium (Mg) and selenium (Se) were selected for this study because of their participation in critical constituents of cells, such as nucleic acids and enzymes in living organisms, and their indirect and direct effects on immunity. Although the separate effects of these inorganic materials are known, there is no study on their combined effects. Galleria mellonella, which is used as a model organism, is frequently used in evaluating of effects of human pathogens due to its various properties. Total hemocyte counts and encapsulation-melanization responses are the most commonly observed parameters when examining the immune responses of this model organism. In our study, the effects of the selected inorganic materials added in the ratio of 0.1%, 0.25%, 0.5% and 1% in the nutrient content of Galleria mellonella on the immune responses of this organism were investigated. As a result of the study, it was found that only 0.25% of the doses increased the hemocyte count and that the other doses significantly decreased compared to the control group. However, it was determined that 0.5% and 1% feeding caused a significant decrease in both hemocyte count and encapsulation-melanization responses. According to our findings, the nutrients which have over a certain dose by inorganic substances have negative effects on immunity.

Machine learning has been actively used in disease detection and segmentation in recent years. For the last few years, the world has been coping with the Coronavirus disease 2019 (COVID-19) pandemic. Chest-computerized tomography (CT) is often a meaningful way to detect and detect patients with possible COVID-19. This study aims to classify COVID-19 and non-COVID-19 chest-CT images using deep learning (DL) algorithms and investigate whether we can achieve successful results in different parameters using four architectures. The study was performed on proved positive COVID-19 CT images, and the datasets were obtained from the GitHub public platform. The study evaluated four different deep learning architectures of VGG16, VGG19, LeNet-5, and MobileNet. The performance evaluations were used with ROC curve, recall, accuracy, F1-score, precision, and Root Mean Square Error (RMSE). MobileNet model showed the best result; F1 score of 95%, the accuracy of 95%, the precision of 100%, recall of 90%, AUC of 95%, and RMSE of 0.23. On the other hand, VGG 19 model gave the lowest performance; F1 score of 90%, the accuracy of 89%, the precision of 90%, recall of 90%, AUC of 89%, and RMSE of 0.32. When the algorithms' performances were compared, the highest accuracy was obtained from MobileNet, LeNet-5, VGG16, and VGG19, respectively. This study has proven the usefulness of deep learning models to detect COVID-19 in chest-CT images based on the proposed model framework. Therefore, it can contribute to the literature in Medical and Engineering in COVID-19 detection research., Makine öğrenmesi, son yıllarda hastalık tespiti ve segmentasyon araştırmalarında aktif olarak kullanılmaktadır. Son yıllarda insanlık, Koronavirus hastalığı 2019 (Covid-19) ile mücadele etmektedir. Göğüs-bilgisayarlı tomografi (BT) görüntüsü, olası Covid-19 hastalarını tespit etme de önemli bir araçtır. Bu çalışma, Derin Öğrenme (DÖ) algoritmaları kullanarak Covid-19 ve Covid-19 olmayan göğüs BT görüntülerini, sınıflandırmayı ve dört mimari kullanarak farklı parametrelerde başarılı sonuçlar elde edip edemeyeceğimizi araştırmayı amaçlamaktadır. Çalışma, kanıtlanmış pozitif Covid-19 CT görüntüleri üzerinde gerçekleştirildi ve görüntüler GitHub kamu platformundan elde edilmiştir. VGG16, VGG19, LeNet-5 ve MobileNet gibi dört farklı derin öğrenme mimarisi değerlendirildi. Performans değerlendirmelerinde ROC eğrisi, duyarlılık, doğruluk, F1-ölçütü, kesinlik ve RMSE kullanılmıştır. MobileNet modeli en iyi sonucu vermiştir sırasıyla; F1-ölçütü %95, doğruluk %95, kesinlik %100, duyarlılık %90, AUC %95 ve RMSE 0.23'tür. En düşük performansı ise; F1-ölçütü %90, doğruluk %89, kesinlik %90, duyarlılık%90, AUC %89 ve RMSE 0.32 ile VGG19 modeli vermiştir. Algoritmaların performansları karşılaştırıldığında en yüksek doğruluk sırasıyla MobileNet, LeNet-5, VGG16 ve VGG19'dan elde edilmiştir. Bu çalışma önerilen modeller çerçevesinde, Covid-19'u tespit etmek için derin öğrenme modellerinin kullanışlılığını göstermiştir. Bu nedenle araştırma, Covid-19 tespit çalışmalarında Tıp ve Mühendislik literatürüne katkı sağlayabilir.

Helichrysum arenarium (L.) (Asterales:Asteraceae) Moench is a therapeutic plant which contains etheric oil, flavones and flavon glycosides, sterins, bitter substances and tannins having various coumarins. This plant is thought to have important characteristics such as diuretic effect, dropping stones and sand from the kidney, regulating digestive disorders, strengthening the immune system, and having antibiotic and antioxidant effects. Additionally, this plant is traditionally used in liver and biliary tract diseases and also shows anti-inflammatory and detoxifying properties. Model organism Galleria mellonella L. (Lepidoptera:Pyralidae) is an invertebrate species that is frequently used to study the effects of human pathogens and various pesticides, hormones, etc. on immune system. In our study, we examined the effect of various doses of H. arenarium on the hemocyte count and behavior of G. mellonella larvae. According to the findings obtained at the end of our study, H. arenarium caused an increase in hemocyte count with the injection of 0.25% and 0.5% doses compared to the untreated and DMSO groups. At the same time, the 0.25% and 0.5% doses showed a strong encapsulation-melanization response and an increase in phenoloxidase enzyme activity over 24 h compared to the other injected groups. Based on these results, H. arenarium extract has an anti-mitotic activity at high doses (above 0.5%). This effect may be due to the fact that the plant extract supports mitosis at a certain dose, while being toxic when exceeding it.

Pyrethrum is a natural neurotoxic insecticide which is obtained from the flowers of Chrysanthemum cinerariaefolium plant. Pyrethrum extract causes DNA damage, genotoxic effect, induction of autophagy and apoptosis, mitochondrial dysfunction, oxidative stress, inhibition of biochemical processes. The greater wax moth Galleria mellonella L. (Lepidoptera: Pyralidae) is gaining increasing attention in immunity studies as an invertebrate model organism. Melanization, which is the most important response of invertebrate humoral immunity, occurs when inactive prophenoloxidase turns into phenoloxidase enzyme. Changes in phenoloxidase enzyme activity are an important marker for humoral immunity. In our study, the phenoloxidase enzyme activity of hemolymph collected from G. mellonella larvae treated with different doses of pyrethrum extract was determined by reading against a certain absorbance in an ELISA microplate reader. The findings obtained from this study showed that 0.6 mg/ml pyrethrum extract increased phenoloxidase enzyme activity. Doses above and below this dose did not cause a significant change in phenoloxidase activity compared to control groups. In the evaluation made in terms of the change of enzyme activity over time, while the enzyme activity increased rapidly in the first 15 minutes, the enzyme activity rate decreased after the 20th minute. The effect of pyrethrum extract on phenoloxidase enzyme activity in G. mellonella larval hemolymph at a certain dose is consistent with the literature. The reason for this effect of the extract is closely related to its genotoxic and cytotoxic effects.

The dietary effects of the well-known auxin member plant growth regulator, indole-3-acetic acid (IAA), on hemocyte counts and behavior of the model insect Galleria mellonella L. (Lepidoptera: Pyralidae) and its parasitoid Pimpla turionellae L. (Hymenoptera: Ichneumonidae) were examined. In vivo and in vitro experiments involved five treatments applied to larvae with doses of 50, 500, 1000, 5000, and 10000 ppm IAA and the controls. Total hemocyte counts increased at all applied IAA doses in G. mellonella whereas no effect was observed in P. turionellae. According to acridine orange-ethidium bromide double staining, none of the IAA doses affected the ratio of apoptotic and mitotic cells in vivo however a decrease in the number of late apoptotic cells at 1000 and 5000 ppm was observed at in vitro experiments in G. mellonella. An increase in the percentage of early apoptotic hemocytes at 1000 ppm and late apoptotic hemocytes at 500 ppm were determined in P. turionellae larvae. IAA also increased the ratio of mitotic hemocytes in the circulation of P. turionellae larvae at 50, 1000, and 10000 ppm. Changes in the encapsulation rate of Sephadex A-25 beads were not significant however the increase at 5000 ppm at 4th hour in non-melanized hemocytes was recorded as compared to the control. A strong decrease in melanization at 50 ppm and an increase at 50 and 1000 ppm in non-melanized bead count at 24 h were also observed. It can be concluded that IAA is inappropriate to use in combination with microbial control agents in IPM programs due to elevated hemocyte counts of the pest.

Objective: In general, while upper respiratory tract viruses cause flu-like complaints, balance problems associated with these viruses are often overlooked. It has been a long time since the first appearance of Covid-19, but unfortunately, there is still no fully effective treatment for this disease. Along with balance manifestations, especially several vestibular symptoms such as dizziness, vertigo, and tinnitus are described as common clinical manifestations in COVID-19. In our study, we investigated the effects of Covid-19 on the balance system with routine balance tests and we tried to localize a possible disorder in the balance system. Materials and Methods: Volunteers were divided into two groups. The number of volunteers in each group was thirty. The first group consisted of SARS-CoV-2-positive patients and the second group consisted of healthy people. Spontaneous nystagmus determination, Romberg test, Fukuda stepping test (FST), head thrust test (HTT), head shake test (HST), finger-nose test, and tandem walking test were applied. Results: The lateral fall in the Romberg test, rotation in the FST, and nystagmus in the HST are significant in Group 1 (p

Zeytin ağacı (Olea europaea) ülkemizin de içerisinde yer aldığı Akdeniz bölgesinde yaygın olarak yetiştirilen bir türdür. Bu ağacın meyvesi ve yağından yararlanıldığı kadar, yapraklarından da halk hekimliğinde yararlanılmaktadır. Antioksidan, anti-enflamatuar ve antibiotik etkilerinin yanında kalp hastalıklarından korunma, karaciğer yağlanması, diabet gibi bazı yaygın hastalıklara karşı da etkili olduğu bilinmektedir. Zeytin yaprağının en önemli bileşeni oleuropeindir. Çalışmamızda; insan patojenleri için sıklıkla kullanılan model organizma Galleria mellonella (Büyük Balmumu Güvesi) kullanılmıştır. Zeytin yaprağı ekstraktı ile muamele edilen G. mellonella larvalarının toplam hemosit sayısı, enkapsülasyon ve melanizasyon bağışıklık tepkileri üzerine etkileri incelenmiştir. Toplam hemosit sayısının tespiti ve enkapsülasyon-melanizasyon tepkilerinin belirlenmesi için faz-kontrast mikroskop kullanılmıştır. Bulgularımıza göre 1000 ppm dozunda zeytin yaprağı ekstraktı bağışıklığı desteklemektedir.

Objective: 85% of neoplasms originating from the major salivary glands are seen in the parotid gland. The diagnosis of parotid masses can sometimes be made with a simple anamnesis and physical examination. However, despite all advanced examinations and biopsies, the preliminary diagnosis can be very different from the postoperative pathological diagnosis due to the unique embryological and anatomical features of the parotid gland. In our study, we aimed to evaluate the relationship between the accuracy of diagnostic tools and postoperative pathological diagnoses in patients who underwent parotidectomy. Materials and Methods: The files of patients who underwent surgery between 2014 and 2019 due to a parotid mass were evaluated. Preoperative neck ultrasound, computed tomography, magnetic resonance imaging, and fine-needle aspiration biopsies were evaluated. Postoperative pathological diagnoses and preoperative examination findings, imaging methods, and preliminary diagnoses obtained according to fine-needle aspiration biopsy results were compared and sensitivity, specificity, and accuracy rates were determined. Results: According to the postoperative pathologic diagnosis, 31 of the tumors were reported as benign (91.1%) and 3 as malignant (8.8%). Ultrasound defined 10 of 17 patients with benign pathology as benign (58.8%) and 7 as nondiagnostic (41.1%). Magnetic resonance imaging reported 11 of 15 benign cases as benign (73.3%), and defined 1 malignant case as nondiagnostic. It was observed that 20 of the patients who underwent fine-needle aspiration biopsy were reported as benign and 4 as nondiagnostic. Postoperative pathology results of 2 of 24 patients were reported as malignant, and 22 of them as benign. Conclusion: Although magnetic resonance imaging gives the most accurate information among the imaging methods evaluated for preoperative parotid masses, it cannot always make a definitive diagnosis. Although fine-needle aspiration biopsy is useful in distinguishing between malignant and benign tumors, malignant tumors can be reported as benign.

It has been reported that acoustic waves are generated when a high-energy pulsed proton beam is deposited in a small volume within tissue. One possible application of proton-induced acoustics is to get real-time feedback for intra-treatment adjustments by monitoring such acoustic waves. A high spatial resolution in ultrasound imaging may reduce proton range uncertainty. Thus, it is crucial to understand the dependence of the acoustic waves on the proton beam characteristics. In this manuscript, firstly, an analytic solution for the proton-induced acoustic wave is presented to reveal the dependence of the signal on the beam parameters; then it is combined with an analytic approximation of the Bragg curve. The influence of the beam energy, pulse duration and beam diameter variation on the acoustic waveform are investigated. Further analysis is performed regarding the Fourier decomposition of the proton-acoustic signals. Our results show that the smaller spill time of the proton beam upsurges the amplitude of the acoustic wave for a constant number of protons, which is hence beneficial for dose monitoring. The increase in the energy of each individual proton in the beam leads to the spatial broadening of the Bragg curve, which also yields acoustic waves of greater amplitude. The pulse duration and the beam width of the proton beam do not affect the central frequency of the acoustic wave, but they change the amplitude of the spectral components.

BackgroundParaglenoid labral cysts (PLCs) around the shoulder are uncommon. Magnetic resonance imaging (MRI) is the primary imaging modality for the description of PLCsPurposeThe purpose of this study was to evaluate PLCs in the posterior part of the glenoid bone via MR arthrography as well as to describe associated labral abnormalities.Material and MethodsThis retrospective study included 14 patients, diagnosed with 15 posterior PLCs at MR arthrography between 2007 and 2012. Conventional MRI and MR arthrography were used for all patients.ResultsA total of 15 PLCs were detected in 14 patients with eight located on the right shoulder and six on the left shoulder. One case had two PLCs. While two cysts were multiloculated, the remaining 13 were seen as unilocated simple cysts. Moreover, 14 of 15 posterior PLCs (60%) were associated with labral tears at MR arthrography. The cysts in proximity to the glenoid labrum were posterosuperior in 33.3% (n = 5), mid-posterior in 36.7% (n = 7), and postero-inferior in 20% (n = 3). The majority of patients with posterosuperior and mid-posterior cysts had an associated superior labral tear from anterior to posterior (SLAP) lesions. Four of six patients with mid-posterior cysts had minimal denervation atrophy in the infraspinatus muscle.ConclusionPosterior PLCs are mostly associated with posterior labral defects. The majority of cysts localized in the posterosuperior and mid-posterior were also associated with SLAP lesions. Denervation atrophy in the infraspinatus muscle may frequently accompany mid-posterior PLCs.

The automatic voltage regulator (AVR) system is an important device that regulates the output voltage of synchronous generator. In this study, it is proposed to use the artificial electric field (AEF) algorithm to adjust the parameters of the proportional + integral + derivative (PID) controller in the AVR system. This algorithm is inspired by the electrostatic force in physics and is one of the most up-to-date meta-heuristic optimization algorithms. The aim of the proposed approach is to improve the step response of AVR system. The transient response performance of the proposed AEF-tuned controller (AEF/PID) was compared with controllers based on some approaches found in literature, taking into account the values of the criteria such as maximum overshoot, settling time, rise time and peak time. The simulation results confirmed that the AEF/PID based AVR system has good potential due to its statistical data and transient response.

In this work, a new nature-inspired, population-based meta-heuristic optimization method, Harris Hawks Optimization (HHO), is applied for the first time for tuning the parameters of both the traditional PID controller and the fractional order PID (FOPID) controller used in a DC-DC buck converter. The PID and FOPID controllers, whose parameters optimally tuned by HHO algorithm, are used for improving the transient response of a DC-DC buck converter by minimizing the maximum overshoot, settling time and rise time of converter's output voltage and for eliminating the steady state error. In addition, to illustrate the superiority of the proposed HHO-PID and HHO-FOPID controllers, beside the transient response analysis, the frequency response analysis and performance indices analysis were also conducted and compared with GA-PID and WOA-PID controllers, which are available in literature and are tuned by genetic algorithm (GA) and whale optimization algorithm (WOA), respectively. The numerical and graphical results demonstrated that the proposed HHO-FOPID controller has better control performance than the proposed HHO-PID, GA-PID, and WOA-PID controllers. The obtained simulation results confirmed the superiority and effectiveness of the proposed HHO-FOPID controller in terms of both algorithm and controller structure.

Sosyalleşme ve iletişim devriminin simgesi olan İnternet’in ortak ürünü olan sosyal medya, adeta alacakaranlıkta sürdürülen ilişkiler sayesinde, bireylerin ideolojik ve sosyal baskılardan uzaklaşmasını sağlayarak yeni bir kimlik alanı da açmaktadır. Popüler sanal ağlardan Instagram ise bu makalenin çalışma alanını oluşturmaktadır. Siber uzayda değişen zaman ve mekân algısı nostalji kavramını da değiştirmiştir. Çağdaş nostalji, geçmiş hakkında olmaktan çok yitip giden şimdi hakkında olmaya başlamıştır. Nostaljinin Instagram’a yansımasını ise #tbt etiketinde görmekteyiz. Türkçeye “Ne günlerdi!” olarak çevirebileceğimiz ve açılımı “Throwback Thursday”in kısaltması olan TBT, geçmişten bir güne, eskilere dair fotoğraf yüklemek isteyenlerin kullandığı bir etiket olarak karşımıza çıkmaktadır. Her gün yaklaşık 450 milyon paylaşımın yapıldığı bu etiket üzerinde yaptığımız çalışmada yöntem olarak, yarı yapılandırılmış soru formuyla derinlemesine görüşmeler gerçekleştirilmiştir. Araştırma sonucunda Instagram alanı üzerinde nostaljinin birkaç günden birkaç seneye uzanan tarih aralığındaki fotoğraflarla yeniden inşa edilse de gerçek hayatta beklenen duygusal tatminin burada gerçekleşmediği görülmüştür

OBJECTIVE We investigated whether preglenoid fat thickness can be used as an ancillary sign for preliminary diagnosis of Bankart and its variants on nonarthrographic magnetic resonance imaging. MATERIALS AND METHODS Sixty-eight anterior dislocation patients were included in this retrospective study. Forty-eight patients with Bankart and its variants, as detected by arthroscopy and magnetic resonance arthrography, were included in the study group. The study group was divided into osseous Bankart, labral Bankart, Perthes, and anterior labroligamentous periosteal sleeve avulsion subgroups. Twenty patients with no detected labral pathologies by arthroscopy and magnetic resonance arthrography were included in the control group. In these patients, preglenoid fat tissue thickness at the anteroinferior portion was measured at the level of the glenoid tubercle. Thickness of preglenoid fat tissue was compared between groups with different labral pathologies and those with normal labrum. RESULTS The preglenoid fat tissue thickness was 2.65 ± 1.05 mm in the control group and 0.90 ± 0.59 mm in the study group (P < 0.0001). Patients with preglenoid fat tissue thinner than 1.6 mm showed a significantly increased likelihood of having Bankart and its variants in receiver operating characteristic analysis (sensitivity of 95.8% and specificity of 85%). There was no significant difference in preglenoid fat tissue thickness between the subgroups of the study group (osseous Bankart, labral Bankart, Perthes, and anterior labroligamentous periosteal sleeve avulsion). CONCLUSION Preglenoid fat tissue measurement can be used as an ancillary sign in the diagnosis of Bankart and Bankart variants in glenohumeral instability patients.

Bu çalışma, ilk kez böbrek-ilhamlı algoritma (KA) kullanarak otomatik gerilim regülatörü (AVR) sisteminin optimal oransal-integral-türevsel (PID) kontrolör parametrelerini (Kp, Ki ve Kd) belirlemek için yeni bir tasarım yöntemi sunmaktadır. KA tekniği yüksek kaliteli çözüm, iyi hesaplama verimliliği ve hızlı yakınsama özelliklerine sahiptir. Önerilen PID kontrolörünün tasarım problemi bir optimizasyon problemi olarak tanımlanmıştır ve Kp, Ki ve Kd’nin optimal kontrolör kazançlarını bulmak için KA tekniği kullanılmıştır. KA tekniği ile optimize edilmiş PID kontrolörünün Ziegler-Nichols (ZN) klasik ayar metoduna ve bazı modern sezgisel optimizasyon algoritmalarına dayalı kontrolörlere göre üstünlüğü, etkin bir AVR sistemi elde etmek için geçici hal cevap analizi yapılarak incelenmiştir. KA tekniği ile ayarlanan ilgili güç sisteminin kararlılığını değerlendirmek için kutup/sıfır haritası analizi ile Bode çizimi gerçekleştirilmiştir. Daha sonra, önerilen kontrolörün performansını AVR sisteminde kontrol etmek için gürbüzlük analizi de yapılmıştır. Sayısal simülasyon sonuçları, KA tekniğinin mükemmel bir ayarlama kabiliyetine sahip olduğunu ve AVR sisteminin diğer mevcut yöntemlere göre basamak cevabını iyileştirmede daha etkili olduğunu doğrulamaktadır.

OBJECTIVE We aimed to investigate the efficacy of the rotational traction method in expanding the joint space and enabling the assessment of an extended surface area. METHODS Sixty patients who underwent computed tomography arthrography were evaluated in the study: 30 with and 30 without the help of rotational traction. The subgroups consisted of patients with adhesive capsulitis, habitual luxation, or labral tears. Areas of obscured joint surface by coalescent cartilages were calculated using computer software, and those belonging to the traction and nontraction groups along with subgroups were compared statistically. RESULTS There was a significant difference between the traction and nontraction group regarding the contact surface area (P < 0.001 for both observers). In patients with adhesive capsulitis, the contact surface area was larger compared with the other subgroups (P = 0.002 for observer 1 and P = 0.002 for observer 2). In patients with habitual luxation, the contact surface area was smaller compared with the other subgroups (P = 0.002 for observer 1 and P = 0.001 for observer 2). CONCLUSIONS Expansion of joint distance is important for assessing the joint cartilage. The rotational traction method provides effective separation of the joint space. For this reason, rotational traction can be used effectively in patients in whom the joint cartilage is to be evaluated.

In this paper, a novel artificial intelligence based optimization method, called salp swarm algorithm (SSA) is applied to determine the optimal proportional, integral, derivative (PID) controller parameters of the automatic voltage regulator (AVR) system. The simplicity of algorithm provides high quality tuning of optimal PID controller parameters. The integral of time weighted squared error (ITSE) as objective function is selected to optimize the controller parameters. The transient response analysis reveals that the SSA method has a better tuning ability and is more efficient in improving the step response of an AVR system than Ziegler-Nichols (ZN) conventional tuning method and artificial bee colony (ABC) algorithm.

Experimental and viscoplastic finite element analysis (FEA) of thermo-mechanical plastic deformation in nonisothermal warm deep drawing is studied using SS304. A nonisothermal deep drawing tool is used in a servo-motor-controlled press. Drawability window of SS304 under elevated temperatures (25–225 °C) and low to high strain rates (drawing speeds of 2.5, 25, and 50 mm/s) were determined. A viscoplastic thermal material model is adopted for nonwork softening material behaviors, as seen in low-temperature forming of SS304, and found to be easily applicable and quite satisfactory. Tensile and equi-biaxial bulge tests were conducted for more accurate flow stress data to be used in FEA. Measured punch load–stroke and cup’s curvilinear thickness (rolling/transverse) curves were successfully compared with predictions from the nonisothermal FE model of the warm deep drawing.

The effect of extrusion method and lubrication on formability of aluminum tubes in hydroforming is experimentally investigated. First, the formability differences between seamless and porthole aluminum 6063 and 6260 alloy tubes, at T1 and T6 heat treatment conditions, are studied using free bulging. Second, the performances of a wide range of lubricants are ranked using zone-dependent friction tests, e.g., guiding zone and expansion zone, which emulate the two different interface mechanics existing in a THF operation. Results showed that seamless tubes, under any condition, give 5 % more expansion compared to porthole. Also, if a tube has T6 condition, seamless shows clear formability advantage over porthole. However, porthole is found to be quite satisfactory for tubes at T1 condition since they achieved more than %10 expansion. “Zone-dependent” (expansion zone and guiding zone) lubrication tests are conducted using wet and dry lubricants. Results showed that while a dry lubricant performed best in the expansion zone, a wet lubricant performed best in the guiding zone.

Elevated temperature hydraulic bulge tests for Mg AZ31-O alloy sheets were conducted using a submerged tool, designed to minimize the temperature variation in the sheet. Experiments were conducted between room temperature and 225 °C, at various approximate true strain rates. Bulge profiles at different bulge heights were measured using a CMM and the best radius values were calculated through least-square fit using several measured points. Residual plots were made to demonstrate the amount of deviation from a sphere with increasing bulge height. Measured and calculated bulge radius and thickness values were compared with the available analytical models. Amount of error that occurs in flow stress calculation by deploying the well-known membrane theory was investigated.

Experimental investigation on the formability limits of aluminum and magnesium alloys are conducted through hydraulic bulging and deep drawing. New tube hydroforming tooling was designed and the submerged tool concept is introduced. Tube hydroforming experiments were conducted with and without axial feed by using AA6061 tubes. The formability of Mg AZ31-O sheets are determined by hydraulic bulging using similar submerged tool. Finally the effect of temperature and initial blank size on the attainable highest punch velocity is investigated and round cups from Mg AZ31-O were successfully formed in a heated tool with punch speeds up to 300 mm/s.

Heat transfer coefficient (HTC) is one of the most important and difficult-to-obtain parameter in high temperature environment. Contact pressure and workpiece surface roughness are among important parameters that affect the heat transfer in elevated temperature forming of sheets. In this study, HTCs are investigated experimentally by using a servo-drive press. With the flexibility that the servo-drive press offers, effect of various blank holder pressures on temperature change is determined. Before and after surface roughness conditions of aluminum and magnesium (from two different manufacturers) alloy sheets are compared. Experimental setup was modeled using deform 2d, and measured temperature curves were compared with the finite element analysis (FEA) predictions and a window of heat transfer coefficients were determined for warm forming of sheets. Determined heat transfer coefficients were implemented in a nonisothermal deep drawing FE model in deform 2d and results were compared with experiments. Good agreement was obtained between FEA predictions and experiments.

Servo presses are recently introduced metal forming machinery and they are in many ways, a hybrid of mechanical and hydraulic presses. They are designed to combine the strengths of conventional mechanical and hydraulic presses, and at the same time to minimize their constraints. The advantages of servo presses in metal forming technology are discussed briefly. Advantages they offer in warm forming are discussed more in detail and demonstrated experimentally. By using the flexibility that the servo press offers, the effect of contact pressure on temperature change and surface roughness of aluminum and magnesium sheet is experimentally investigated. Non-isothermal warm forming is introduced and studied experimentally. Combined advantages of the non-isothermal approach and the servo motor controlled press are demonstrated by introducing a variable forming speed concept. As a result, 60% savings in cup drawing time is achieved experimentally. Measured temperature curves were used in FEA to determine heat transfer coefficients. Effect of the determined heat transfer coefficients on deep drawing was analyzed using FEA and good agreement were obtained between FEA predictions and experimental measurements.Copyright © 2010 by ASME

Weight reduction is one of the major goals in the automotive, appliance, and electronics industries. One way of achieving this goal is to use lightweight alloys such as aluminum and magnesium that have high strength to weight ratios. However, due to their limited formability at room temperature, forming needs to take place at elevated temperatures and mostly under nonisothermal conditions. In this study, nonisothermal deep drawing process using aluminum and magnesium alloys was investigated using a servo motor driven press and a heated tool set. Using the flexibility of the servo press kinematics, blanks were heated in the tool set prior to forming. Temperature-time measurements were made at various blank holder interface pressures in order to determine the required dwell time to heat the blank to the forming temperature. Several lubricants for elevated temperature forming were evaluated using the deep draw test, and a PTFE based film was found to be the best performing lubricant. Deep drawing tests were conducted to determine the process window (maximum punch velocity as functions of blank size and temperature) for Al 5754-O and Mg AZ31-O. Maximum punch velocities of 35 mm/s and 300 mm/s were obtained for the Al and Mg alloys, respectively. Comparisons for the Mg alloy sheets from two different suppliers were made and significant differences in formability were found. Experiments were conducted in order to understand the effect of constant and variable punch velocity and the temperature on the mechanics of deformation. Variable punch velocity is found to improve the thickness distribution of the formed part.