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Internship experience for learning the operation of a cable-driven robot for rehabilitation tasks
No full text2nd International Symposium on the Education in Mechanism and Machine Science (ISEMMS); NOV 23-24, 2017; Madrid, SpainThis paper describes an example of internship experience at LARM, Laboratory of Robotics and Mechatronics, at University of Cassino and South Latium. In particular, the main focus of this paper is the learning process as basis of a proper internship. Namely, a specific experiential learning approach is proposed as referring to a low-cost servo motor operation task. The learning task is further defined and developed as referring to a real application with a cable-driven robot for rehabilitation tasks, which has been designed and built at LARM in Cassino and under further investigation within Agewell project
On the non-linear integral equation method for the reconstruction of an inclusion in the elastic body
No full textWe apply the non-linear integral equation approach based on elastic potentials for determining the shape of a bounded object in the elastostatic two-dimensional domain from given Cauchy data on its boundary. The iterative algorithm is developed for the numerical solution of obtained integral equations. We find the Frechet derivative for the corresponding operator and show unique solviability of the linearized system. Full discretization of the system is realized by a trigonometric quadrature method. Due to the inherited ill-possedness in the system of linear equations we apply the Tikhonov regularization. The numerical results show that the proposed method gives a good accuracy of reconstructions with an economical computational cost
Meme Kanseri Hücrelerinin Fosfolipit Hücre Zarı ile Etkileşimlerinin İncelenmesi
No full textObjective: Circulating tumor cells have an important role in the pathogenesis of metastasis. Metastasis occurs through few steps including arrival of circulating tumor cells to distant tissue and organs, their adherence to the target tissue, and then formation of a new tumor. To understand the mechanism of this process it is necessary to investigate the interaction of cancer cells with other molecules and cells of the target tissue, and most importantly interaction with lipids forming the cellular membrane. Methods: To better understand the process of cancer cell adhesion onto lipid membranes and the ionic interactions that are involved in cell adherence, surfaces functionalized with tethered bilayer lipid membrane (tBLM) were utilized in this work as an experimental platform. Either lipid surfaces functionalized with cationic POEPC: PC or anionic POPS: PC fwere examined to observe the ionic interaction of charged phospholipid membrane and MDA-MB231 breast cancer cells. Results: Adhesions of MDA-MB-231 breast cancer cells and NIH-3T3 mouse fibroblast cells to positively charged POEPC: PC lipid surfaces,and their dissemination was observed during examinations using Surface Plasmon Resonance (SPR) method. The results were further confirmed with cell viability and proliferation studies that shows cationic POEPC: PC lipid surfaces were able to facilitate and increase the cell adhesion. Conclusion: These results reveal the cationic phospholipid structures favour the enhanced cancer cell adhesion.Amaç: Dolaşımdaki kanser hücrelerinin metastaz oluşmasındaki rolleri önemlidir. Metastaz kanser hücrelerinin diğer organ ve dokulara ulaşması, ve sonrasında hedef dokuya tutunması sonucunda yeni bir tümör oluşumunun başlaması ile gerçekleşir. Bu mekanizmanın çözümlenebilmesi için kanser hücrelerinin hedef dokudaki diğer moleküllerle, hücrelerle ve en önemlisi hücre zarını oluşturan lipitlerle etkileşiminin incelenmesi gerekmektedir. Yöntem: Bu çalışmada, kanser hücrelerinin fosfolipit hücre zarına tutunma sürecini ve hücre tutunmasına etki eden iyonik etkileşimleri daha iyi anlayabilmek için yüzeye tutturulmuş katmanlı lipit membranlar (tBLM) ile fonksiyonlandırılmış yüzeyler deneysel platform olarak kullanılmıştır. Katyonik POEPC: PC veya anyonik POPS: PC ile fonksiyonlanmış lipit yüzeyler, fosfolipit hücre zarı ve MDA-MB-231 meme kanseri hücreleri arasındaki iyonik etkileşimi gözlemlemek için incelendi. Bulgular: Yüzey Plazmonu Rezonansı (SPR) ile yapılan incelemelerde MDA-MB-231 meme kanseri hücrelerinin ve NIH-3T3 fare fibroblast hücrelerinin pozitif yüklü POEPC: PC lipit yüzeylere tutunduğu ve yayıldığı gözlemlendi. Bu sonuçlar ayrıca hücre canlılığı ve hücre büyümesi analizleri ile doğrulanarak katyonik POEPC: PC lipit yüzeylerinin hücre tutunması prosesini hızlandırdığı ve artışa neden olur yönde etkilediği gözlemlendi. Sonuç: Elde edilen sonuçlar katyonik fosfolipit yapının fazla olduğu hücre zarının kanser hücrelerinin tutunmasını kolaylaştırdığını kanıtlamaktadır
SEMA6D'nin onkogenik rolünün meme kanseri hücrelerinde incelenmesi
No full textThesis (Master)--Izmir Institute of Technology, Molecular Biology and Genetics, Izmir, 2019Includes bibliographical references (leaves: 45-51)Text in English; Abstract: Turkish and EnglishBreast cancer, the most commonly diagnosed cancer type and the leading cause of cancer-associated deaths, is the major health issue among women worldwide. In many cancer types, the expression of the semaphorins and their receptors such as plexins and neuropilins are dysregulated. SEMA6D is a member of class-6 family transmembrane semaphorin proteins and acts through Plexin-A1 receptor. It was previously shown that overexpression of SEMA6D in breast cancer cell line MCF-7 leads to a reduction in proliferation and an increase in migration. On the other hand, in the MDA-MB-231 breast cancer cell line, overexpression of SEMA6D had no significant effect on proliferation but enhanced migration. In this study, we aimed to analyze the effects of SEMA6D overexpression in normal breast cell line MCF10A and investigate the invasive behavior and transformation capacity of SEMA6D overexpressing breast cancer cell lines. We demonstrated that overexpression of SEMA6D leads to elevated proliferation, viability and migration in MCF10A cells, whereas it did not trigger their anchorage-independent growth. On the other hand, MDA-MB-231 and MCF7 cells stably expressing SEMA6D showed reduced colony formation in the soft-agar assay. Furthermore, the invasiveness of MDA-MB-231 cells was elevated with SEMA6D overexpression, whereas SEMA6D overexpression did not stimulate the invasiveness of MCF-7 cells through matrigel microenvironment, whereas slightly trigger invasion through bone microenvironment. In conclusion, SEMA6D overexpression has cell-specific effects on breast cancer. The exact role of SEMA6D in breast cancer development remains undefined and must be further investigated.Meme kanseri, kadınlarda en sık teşhis edilen kanser türü olmakla birlikte dünya çapında kansere bağlı ölümlerin ikinci önde gelen nedenidir. Bir çok insanda bulunan kanser çeşitlerinde semaphorinler ve receptörleri olan plexin ve neuropilinler anormal bir şekilde ekspres edilmektedir. SEMA6D, grup 6 transmembran semaphorin proteinlerinin bir üyesidir ve sinyalini hedef yerlere reseptörü olan Plexin-A1 ile iletir. Önceki çalışmalarımızda, SEMA6D aşırı ekspresyonunun MCF-7 meme kanseri hücrelerinin proliferasyonunda azalmaya sebep olduğu ancak hücre göçünde artışa sebep olduğu gösterilmiştir. MDA-MB-231 meme kanseri hücresinde ise, SEMA6D fazla ekspresyonu proliferasyonu anlamlı olarak etkilemezken hücre göçünü arttırdığı gözlemlenmiştir. Bu çalışmada, SEMA6D aşırı ekspresyonunun MCF10A normal meme epitel hücrelerindeki etkisinin araştırılması ve meme kanseri hücrelerindeki invazif davranışları ve transformasyon kapasitesi üzerine etkisinin incelenmesi hedeflenmiştir. MCF10A hücrelerinde SEMA6D fazla ekspresyonunun proliferasyonda ve hücre göçünde artışa sebep olduğu gösterilmiştir, ancak yumuşak agarda herhangi bir koloni oluşumu gözlenmemiştir. Meme kanseri hücreleri olan MDA-MB-231 ve MCF-7 da SEMA6D fazla-ifadesi yumuşak agarda koloni oluşumunu azaltmıştır. SEMA6D fazla-ifade edildiğinde MDA-MB-231 hücrelerinin invazif karakterini arttırmıştır ancak invazif olmayan MCF-7 hücre hattında matrigel mikro çevresine doğru invasyonu tetiklememiştir fakat kemik mikro ortamına doğru invazyon görülmüştür. Sonuç olarak SEMA6D kanser ilerlemesinde hücre spesifik olarak önemli bir role sahiptir. SEMA6D' nin meme kanseri gelişimindeki net rolü halen belirsizliğini korumaktadır ve daha detaylı olarak incelenmelidir
Parmak izi eşleştirme algoritmalarının sentetik bozulmalara karşı dayanıklılığı
No full textThesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2019Includes bibliographical references (leaves: 40-43)Text in English; Abstract: Turkish and EnglishFingerprint recognition is one of the biometric techniques used for the identification of humans. The developments and research about fingerprint recognition to date are of great importance in advancing fingerprint recognition and verification scenarios. The fact that fingerprint recognition systems are used almost everywhere and are easily accessible is directly proportionate to a large amount of research in these areas. During the acquisition of the fingerprint, there are many environmental factors that may affect the quality of the print and eventually, its ability to be recognized. For a fingerprint recognition algorithms, it is important to handle the difficulties that arise due to those variations. The aim of the thesis is to obtain and compare the results of not only an existing feature-based fingerprint recognition techniques but a fingerprint recognition technique that uses deep learning. The main focus is on how fingerprint verification algorithms behave under the circumstances of synthetically distorted fingerprint images. After developing two different verification systems, the goal is to compare system results with and without distorted images. The results of the two methods with and without externally added deformations effect on the fingerprint image is compared. The first system has a feature-based approach comparing the images via local features on the fingerprint. In order to do this two different descriptors that are called ORB and SIFT are used. In the feature-based approach, there is also a matching part and this part is tried with two different matching algorithms that are called Brute Force Matcher and Approximate Nearest Neighbor (ANN) matcher. The second algorithm makes the decision of match or non-match by feeding the raw fingerprint images as an input to a deep neural network and comparing the feature vectors calculated by the network. This study has revealed that deep neural network approach has given more robust and faster results on both the original dataset and distorted versions of the dataset.Parmak izi tanıma, insanların tanımlanmasında kullanılan biyometrik tekniklerden biridir. Parmak izi tanıma konusundaki gelişmeler ve araştırmalar, parmak izi tanıma ve doğrulama senaryolarının geliştirilmesinde büyük öneme sahiptir. Parmak izi tanıma sistemlerinin hemen hemen her yerde kullanılması ve kolayca erişilebilir olması, bu alanlarda yapılan araştırmalarla doğrudan orantılıdır. Bir yüzey üzerinde parmak izi alırken, büyük olasılıkla bazı sorunlar olacaktır ve bu durum parmak izi tanıma performansını etkiler. Güvenli bir tanıma sistemi için bu tür sorunların sisteme nasıl tepki vereceği önemlidir. Tezin amacı sadece mevcut özellik tabanlı parmak izi tanıma tekniklerinin değil aynı zamanda derin öğrenme, görüntü işleme temeli alan parmak izi tanıma tekniklerinin sonuçlarını elde etmek ve karşılaştırmaktır. Önemli olan, parmak izi doğrulama algoritmalarının sentetik olarak bozulmuş parmak izi görüntülerinin koşulları altında nasıl sonuçlar verdiğidir. İki farklı doğrulama sistemi geliştirdikten sonra, sistem sonuçlarını çarpık görüntülerle ve düzgün görüntülerle karşılaştırmaktır. Parmak izi görüntüsü üzeri harici olarak deformasyon etkisi olan ve olmayan iki yöntemin sonuçları karşılaştırılır. İlk sistem, görüntüleri parmak izi üzerindeki özelliklerle karşılaştıran özellik tabanlı bir tanıma sürümüdür. Bunu yapmak için ORB ve SIFT teknikleriyle iki farklı tanımlayıcı kullanılır. Bu konvansiyonel yaklaşımda, eşleşen bir parça da vardır ve bu kısım Brute Force Matcher ve Yaklaşık En Yakın Komşu (ANN) eşleştiricisi olarak adlandırılan iki farklı eşleştirme algoritmasıyla denenir. İkinci algoritma, ham parmak izi görüntülerini modele giriş olarak alarak parmak izi görüntülerini eşleştirmek için tamamen sinir ağı modelinin sonucunu alarak eşleştirme sonuçlarını belirler. Bu çalışma, derin sinir ağı yaklaşımının hem orijinal veri setinde hem de veri setinin çarpık versiyonlarında daha sağlam ve daha hızlı sonuçlar verdiğini ortaya koydu
Akut lenfoblastik lösemi(all) hücrelerinde luteolinin terapötik potansiyelinin belirlenmesi
No full textThesis (Master)--Izmir Institute of Technology, Molecular Biology and Genetics, Izmir, 2019Includes bibliographical references (leaves: 77-99)Text in English; Abstract: Turkish and EnglishAcute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by increased level of immature lymphoblasts in bone marrow and peripheral blood. The developments of lymphoblasts are genetically/epigenetically inhibited. One of the most common genetic abnormalities in ALL is BCR/ABL translocation which regulates the several pathways related to proliferation, anti-apoptotic and drug resistance through its aberrant tyrosine kinase activity. Although the current treatment strategies include targeting BCR/ABL via tyrosine kinase inhibitors; complete remission, overall survival and mortality of Ph+ ALL patients are still worse as compared to Ph- ALL patients. Therefore, new strategies combined with current treatments are needed for Ph+ ALL patients who are qualified as high risk group of ALL. Different studies showed thatluteolin has anti-cancer and anti-tumor effects on wide range cancer types including breast, colon, lung cancer except ALL in both in vitro and in vivo. In this study, the dose and time dependent cytotoxic, apoptotic and cytostatic effects of luteolin on Philadelphia chromosome +ALL cells were determined for the first time. Besides, the effect of luteolin on cell growth and proliferation of two different healthy cell lines was shown. Moreover, the effect of luteolin on bioactive sphingolipids genes which regulate the several pathways including cell proliferation, apoptosis, drug resistance and senescence in cell was determined in Ph positive ALL cells for the first time. As a consequence, luteolin has cytotoxic, apoptotic and cytostatic effects on Ph positive ALL cells and bioactive sphingolipids genes are regulated in this therapeutic potential by luteolin.Akut lenfobalstik Lösemi (ALL) kemik iliğinde ve periferal kanda erken evredeki gelişimi genetik/epigenetik faktörlerle inhibe olmuş ve olgunlaşmamış lenfoblasthücrelerinin artışı ile karakterize malign bir hematolojik kanserdir. ALL'de karşımıza çıkan yaygın genetik anomalilerden biriPhiladelphia kromozomu olarak adlandırılan BCR/ABL translokasyonudur. BCR/ABL aşırı tirozinkinaz anlatımına sahip olup, kanserli hücrelerde hücre çoğalması, anti-apoptoz, metastaz ve ilaç dirençliliğiyleilişkili birçok yolağı aktive etmektedir. Günümüzde klasik kemoterapiye ek olarak BCR/ABL'i hedef alan, BCR/ABL'intirozinkinaz aktivitesini bastırmak veya inhibe etmek üzere tirozinkinaz inhibitörleri kullanılmaktadır. Yine de Ph kromozomu taşımayan ALL hastaları ile kıyaslandığında Ph kromozomu pozitif ALL hastalarında tam remisyon sağlanamamaktadır. Bu nedenle tedaviye yönelik yeni stratejilerin geliştirilmesi oldukça önem arz etmektedir. Yapılan birçok in vitro ve in vivoçalışmadabir flavonoid olan luteolinin meme, akciğer, kolon gibi birçok farklı kanser türlerinde anti- kanser ve anti-tümör etkiye sahip olduğu gösterilmiş olup ALL üzerindeki etkisi gösterilmemiştir. Bu çalışmada, luteolininzamana ve doza bağımlı sitotoksik, apoptotik ve sitostatik etkileri Ph kromozomu pozitif ALL hücreleriiçinterapötikpotansiyeli ilk defa belirlenmiş olup, luteolinin hücre büyümesi ve çoğalması üzerine etkisi iki farklı sağlıklı hücre hatlarında da gösterilmiştir.Bunun yanı sıraluteolininhücre çoğalması, apoptoz, ilaç dirençliliği, yaşlanma gibi birçok metabolizmada rol alan biyoaktifsfingolipid genleri üzerine etkisi de Ph pozitif ALL hücrelerinde ilk defa çalışmamızla gösterilmiştir. Sonuç olarak, elde edilen bulgular luteolininPh pozitif ALL hücreleri üzerinde sitotoksik, apoptotik ve sitostatik etkileri olduğunu, bununla birlikte luteolinin bu terapötik potansiyeldebiyoaktifsphingolipid genlerini de regüle ettiğini gösterilmiştir.TUBITAK (118Z653
Mineralization of olive mill wastewater under hydrothermal conditions
No full textOlive mill wastewater (OMW) is highly dangerous for land and aquatic environments because of its high phenolic content, acidity, and salinity. Hence, hydrothermal degradation of OMW in subcritical water medium with and without using external oxidizer (H2O2) was studied to decrease its total organic carbon (TOC), total phenolic content (TPC), and color. Effects of reaction temperature (150 degrees C-250 degrees C), reaction time (30-120 min), and H2O2 content (0-100 mM) on TOC and TPC of OMW were investigated. Box-Behnken-type experimental design and statistical analysis (analysis of variance) were practiced by Design Expert 11. According to statistical analysis, effect of reaction temperature significantly affected TOC removal efficiency. The best TOC reduction (31.65%) was achieved without using H2O2 at 250 degrees C for 120 min
Pseudo-backstepping and its application to the control of Korteweg de vries equation from the right endpoint on a finite domain
No full textIn this paper, we design Dirichlet-Neumann boundary feedback controllers for the Korteweg-de Vries equation that act at the right endpoint of the domain. The length of the domain is allowed to be critical. Constructing backstepping controllers that act at the right endpoint of the domain is more challenging than its left endpoint counterpart. The standard application of the backstepping method fails, because corresponding kernel models become overdetermined. In order to deal with this difficulty, we introduce the pseudo-backstepping method, which uses a pseudo-kernel that satisfies all but one desirable boundary condition. Moreover, various norms of the pseudo-kernel can be controlled through a parameter in one of its boundary conditions. We prove that the boundary controllers constructed via this pseudo-kernel still exponentially stabilize the system with the cost of a low exponential rate of decay. We show that a single Dirichlet controller is sufficient for exponential stabilization with a slower rate of decay. We also consider a second order feedback law acting at the right Dirichlet boundary condition. We show that this approach works if the main equation includes only the third order term, while the same problem remains open if the main equation involves the first order and/or the nonlinear terms. At the end of the paper, we give numerical simulations to illustrate the main result
Stem cell therapy for multiple sclerosis
No full textPubMed: 30039439Multiple sclerosis (MS) is a chronic inflammatory, autoimmune, and neurodegenerative disease of the central nervous system (CNS). It is characterized by demyelination and neuronal loss that is induced by attack of autoreactive T cells to the myelin sheath and endogenous remyelination failure, eventually leading to functional neurological disability. Although recent evidence suggests that MS relapses are induced by environmental and exogenous triggers such as viral infections in a genetic background, its very complex pathogenesis is not completely understood. Therefore, the efficiency of current immunosuppression-based therapies of MS is too low, and emerging disease-modifying immunomodulatory agents such as fingolimod and dimethyl fumarate cannot stop progressive neurodegenerative process. Thus, the cell replacement therapy approach that aims to overcome neuronal cell loss and remyelination failure and to increase endogenous myelin repair capacity is considered as an alternative treatment option. A wide variety of preclinical studies, using experimental autoimmune encephalomyelitis model of MS, have recently shown that grafted cells with different origins including mesenchymal stem cells (MSCs), neural precursor and stem cells, and induced-pluripotent stem cells have the ability to repair CNS lesions and to recover functional neurological deficits. The results of ongoing autologous hematopoietic stem cell therapy studies, with the advantage of peripheral administration to the patients, have suggested that cell replacement therapy is also a feasible option for immunomodulatory treatment of MS. In this chapter, we overview cell sources and applications of the stem cell therapy for treatment of MS. We also discuss challenges including those associated with administration route, immune responses to grafted cells, integration of these cells to existing neural circuits, and risk of tumor growth. Finally, future prospects of stem cell therapy for MS are addressed
Search for single production of vector-like quarks decaying to a b quark and a Higgs boson
No full textA search is presented for single production of heavy vector-like quarks (B) that decay to a Higgs boson and a b quark, with the Higgs boson decaying to a highly boosted b b ¯ pair reconstructed as a single collimated jet. The analysis is based on data collected by the CMS experiment in proton-proton collisions at s=13 TeV, corresponding to an integrated luminosity of 35.9 fb−1. The data are consistent with background expectations, and upper limits at 95% confidence level on the product of the B quark cross section and the branching fraction are obtained in the range 1.28–0.07 pb, for a narrow B quark with a mass between 700 and 1800 GeV. The production of B quarks with widths of 10, 20 and 30% of the resonance mass is also considered, and the sensitivities obtained are similar to those achieved in the narrow width case. This is the first search at the CERN LHC for the single production of a B quark through its fully hadronic decay channel, and the first study considering finite resonance widths of the B quark.The Scientific and Technical Research Council of Turkey, and Turkish Atomic Energy Authorit