TOBB ETU GCRIS Database
Not a member yet
9778 research outputs found
Sort by
Multichannel Multimodal Piezoelectric Middle Ear Implant Concept Based on Mems Technology for Next-Generation Fully Implantable Cochlear Implant Applications
No full textThis paper introduces a unique multimode, multichannel piezoelectric vibration sensor for the next-generation fully implantable cochlear implant (FICI) systems. The sensor, which can be implanted on the middle ear chain to collect and filter the ambient sound in eight frequency bands, comprises an array of 4 M-shape multimode and 11 single cantilevers. Finite element (FE) analysis indicates a 2.05-fold improvement in capturing frequency information for the multimodal sensor compared to its single-mode counterpart. Under an acoustic excitation at 100 dB SPL, the sensor, mounted on an artificial tympanic membrane, yielded a peak output voltage of 546.16 mVpp and a peak sensitivity of 285.28 mVpp/Pa at 1613 Hz. The extrapolated acoustic results indicated a dynamic frequency range between 300 Hz and 6 kHz, even at 30 dB SPL. Furthermore, a lightweight titanium coupler, employing a two-sided clipping structure with a maximum wall thickness of 70 μm, is micromachined for surgical attachment of the transducer to the middle ear chain. A commercial accelerometer, implanted on the incus short process (SP) of a cadaver using the titanium coupler, successfully recorded 0.1 g for 100 dB SPL at 500 Hz, revealing the potential feasibility of the coupler for vibration sensor implantation. Moreover, the presented anatomically accurate FE model of the middle ear, exhibiting a high correlation coefficient (R2) of 0.97 with the cadaveric experiment, suggests an efficient numerical approach for evaluating the implantation of middle ear prostheses. In this regard, the study holds great promise for clinical application in the field of implantable hearing aids. © 2024 The Author
Accurate informatic modeling of tooth enamel pellicle interactions by training substitution matrices with Mat4Pep
No full textExtracellular matrices direct the formation of mineral constituents into self-assembled mineralized tissues. We investigate the protein and mineral constituents to better understand the underlying mechanisms that lead to mineralized tissue formation. Specifically, we study the protein-hydroxyapatite interactions that govern the development and homeostasis of teeth and bone in the oral cavity. Characterization would enable improvements in the design of peptides to regenerate mineralized tissues and control attachments such as ligaments and dental plaque. Progress has been limited because no available methods produce robust data for assessing organic-mineral interfaces. We show that tooth enamel pellicle peptides contain subtle sequence similarities that encode hydroxyapatite binding mechanisms by segregating pellicle peptides from control sequences using our previously developed substitution matrix-based peptide comparison protocol with improvements. Sampling diverse matrices, adding biological control sequences, and optimizing matrix refinement algorithms improve discrimination from 0.81 to 0.99 AUC in leave-one-out experiments. Other contemporary methods fail regarding this problem. We find hydroxyapatite interaction sequence patterns by applying the resulting selected refined matrix ("pellitrix") to cluster the peptides and build subgroup alignments. We identify putative hydroxyapatite maturation domains by application to enamel biomineralization proteins and prioritize putative novel pellicle peptides identified by In-StageTip (iST) mass spectrometry. The sequence comparison protocol outperforms other contemporary options for this small and heterogeneous group and is generalized for application to any group of peptides. As a result, this platform has broad impacts on peptide design, with direct applications to microbiology, biomaterial design, and tissue engineering.The authors thank Dr. Hector Huang for his help with mass spectrometry, Dr. Arun Witta for provision of time on the mass spectrometer, and Dr. Bill Landis for his help in directing revisions.U.S. Department of Energy10.13039/10000001
Validity and Diagnostic Ability of Pancreatic Exocrine Insufficiency Questionnaire in Turkish Patients
No full textBackground/Aims: Pancreatic exocrine insufficiency (PEI) is a prevalent disease that is often underdiagnosed and undertreated, leading to resulting in diminished health-related quality of life. The PEI questionnaire (PEI-Q), a patient-reported outcome questionnaire devel- oped to diagnose and evaluate PEI, is available only in English. The study aimed to provide a Turkish translation of PEI-Q and validate its reliability and diagnostic performance in a Turkish-speaking population with PEI. Materials and Methods: This study included 161 participants: 98 patients with PEI and 63 healthy controls. Participants underwent the PEI-Q test, and the results were statistically analyzed for reliability and validity. The diagnostic value of PEI-Q was determined using receiver operating characteristic (ROC) curves. Cronbach’s alpha was used to assess internal consistency, while exploratory factor analy- sis was performed to determine construct validity and reveal the factor structure. Results: The mean age of participants was 45.0 years, and 60.2% were male. Participants with PEI were significantly older than those without. Scores for abdominal, bowel movement, and total symptoms were significantly higher in patients with PEI than in controls. ROC analysis revealed good diagnostic value for PEI-Q, with areas under the curve ranging from 0.798 to 0.851 for different symptom scores. Cronbach’s alpha coefficients were above 0.70, indicating good internal consistency, and exploratory factor analysis supported a 4-fac- tor structure, accounting for 68.9% of the total variance. Conclusion: The Turkish version of the PEI-Q is a reliable, easy-to-use, and valid screening tool for diagnosing PEI. It consistently assesses symptoms and quality of life in patients with PEI, helping to inform diagnosis and treatment
Söylemsel Bir İnşa Olarak Kuşak ve Yol Girişimi: Eleştirel Jeopolitik Bir Analiz
No full textÇin Halk Cumhuriyeti tarafından 2013 yılında duyurulan Kuşak ve Yol Girişimi (KYG) halen uluslararası siyasetin önemli tartışma konularından birisidir. Bu makale, girişimi eleştirel jeopolitik bir yaklaşımla ele alarak Çin resmi makamları ve Çin üniversitelerine mensup akademisyenlerin KYG’ye yönelik ürettikleri söylemleri incelemektedir. Bu amaçla makalede, Çin resmi makamları ve Çin akademyasınca üretilen metinler içerik analizi ve söylem analizi yoluyla incelenerek KYG’ye ilişkin söylemin ve bu söylem inşası sürecinde iktidar ile akademya arasındaki ilişkinin niteliklerini ortaya koymak amaçlanmaktadır. Makalede Çin hükümeti ve Çin akademyasının KYG’yi tasvir etmek adına ürettiği bilgi sorunsallaştırılmakta, bu iki söylemin tamamlayıcı nitelikte oldukları ve üretilen bilgilerin Çin’in çıkarlarına hizmet etmek üzere araçsallaştırıldığı gösterilmektedir. Bu yolla Çin’in KYG coğrafyasına yönelik alansallaştırma pratiklerini resmi ve akademik söylem aracılığıyla gerçekleştirdiği gözler önüne serilmektedir
Dynamic Deformation Behavior of the Electron Beam Melted Ti-6al Alloy
No full textIn this study, dynamic deformation behavior of electron beam melted Ti-6Al-4V alloy and effect of initial defects on deformation process of the alloy were investigated with high strain rate experimental and numerical studies. Dynamic compression tests at the strain rates of 350, 850, 1250, 1750, 1950, and 2500/s at room temperature and at higher temperatures of 150 and 240 degrees C were performed using a split-Hopkinson pressure bar. Compression simulations in three dimensions (3D) with LS-Dyna software were conducted using the determined Johnson-Cook parameters of the Ti-6Al-4V alloy specimens, to assess the strain, temperature distribution during deformation. In addition, simulation studies with initial defects in the model were performed to investigate the effect of these defects on strain formation during compression. The experimental results showed that strain rates over 1250/s caused failure at 45 degrees to the loading direction. Adiabatic shear bands were observed for the specimens compressed at the strain rates of 1250/s and higher. As strain rate increased from 1250 to 2500/s, the type of adiabatic shear band altered from deformed to transformed type. The simulation results showed that initial defects in the specimen led to formation of higher plastic strain in the direction of 45 degrees around initial defects. This high strain might be the cause of formation of adiabatic shear band. The simulation results also indicated that void morphology could affect strain distribution in the specimen.Scientific and Technological Research Council of Turkey; TOBB University of Economics and Technology; TUBITAK Defense Industries Research and Development Institute; Presidency of Defense Industries; Turkish AerospaceThis study was supported by the TOBB University of Economics and Technology and the TUBITAK Defense Industries Research and Development Institute. Support through the Presidency of Defense Industries and the Turkish Aerospace under the SAYP project DDKIT1 is also gratefully acknowledged
Maritime Trade Routes Are Necessary for Globalization: The Case of Türkiye
No full textBu çalışma, Türkiye merkezli alternatif ticaret yolları girişimlerini karşılıklı bağımlılık ve barış teorik perspektifinden incelemekte; deniz ticaretinin gerekliliğini vurgulamaktadır. Geçmişte, İpek Yolu gibi kara güzergahları her zaman karşılıklı bağımlılık ilişkileri yaratmadı. Ancak bugün, gerek Yeni İpek Yolu gerek diğer alternatif rotalar yeni bağımlılık ağlarını teşvik etmekte. Bu ticaret ağında deniz rotaları da mühim önem tutmaktadır. Ayrıca karşılıklı bağımlılık ve uluslararası çatışmalar arasında da güçlü bir bağ olduğu düşünülmektedir. Bu çalışma ticaret rotaları ve uluslararası çatışmaları Türkiye özelinde incelemektedir. Çalışmada öncelikle karşılıklı bağımlılık ve çatışmalara ilişkin literatür incelenerek karşılıklı bağımlılık ve küreselleşme kavramları tartışılmaktadır. İkinci bölümde Türkiye'nin mevcut krizlerdeki rolü ele alınmaktadır. Daha sonra uluslararası ticaret yolları ve Türkiye'nin girişimleri değerlendirilmektedir. Sonuçlar, Türkiye'nin çeşitli bölgelerle alternatifler geliştirmesinin gerekliliğini vurgulamaktadır.This study analyzes Türkiye centered alternative trade routes initiatives from an interdependence and peace theoretical perspective; recognizing necessity of maritime trade. Land routes such as the Silk-Road in the past did not necessarily create an interdependent relationship. However, today, both the New Silk Road and other alternative routes encourage new dependency networks. Maritime routes are also of great importance in this trade network. It is also thought that there is a strong link between interdependence and international conflicts. This study examines trade routes and international conflicts specifically for Türkiye. First the concepts of interdependence and globalization are discussed by examining literature on interdependence and conflicts. Second part discusses Türkiye’s role in the midst of current crises. Then international trade routes and Türkiye’s initiatives are assessed. The conclusions highlights necessity for Türkiye to develop alternatives with several regions
Precise Test of Lepton Flavour Universality in i>w/I>-boson Decays Into Muons and Electrons in i>pp/I> Collisions at √i>s/I>=13 Tev With the Atlas Detector
No full textThe ratio of branching ratios of the W boson to muons and electrons, R-W(mu/e) = B(W -> mu nu)/B(W -> e nu), has been measured using 140 fb(-1) of pp collision data at root s = 13TeV collected with the ATLAS detector at the LHC, probing the universality of lepton couplings. The ratio is obtained from measurements of the t (t) over bar production cross-section in the ee, e mu and mu mu dilepton final states. To reduce systematic uncertainties, it is normalised by the square root of the corresponding ratio R-Z(mu mu/ee) for the Z boson measured in inclusive Z -> ee and Z -> mu mu events. By using the precise value of R-Z(mu mu/ee) determined from e(+)e(-) colliders, the ratio R-W(mu/e) is determined to be R-W(mu/e) = 0.9995 +/- 0.0022 (stat) +/- 0.0036 (syst) +/- 0.0014 (ext). The three uncertainties correspond to data statistics, experimental systematics and the external measurement of R-Z(mu mu/ee), giving a total uncertainty of 0.0045, and confirming the Standard Model assumption of lepton flavour universality in W-boson decays at the 0.5% level.We thank CERN for the very successful operation of the LHC and its injectors, as well as the support staff at CERN and at our institutions worldwide without whom ATLAS could not be operated efficiently. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN, the ATLAS Tier-1 facilities at TRIUMF/SFU (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), RAL (UK) and BNL (USA), the Tier-2 facilities worldwide and large non-WLCG resource providers. Major contributors of computing resources are listed in Ref. [83]. We gratefully acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOST and NSFC, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRFand DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MNiSW, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taipei; TENMAK, Turkiye; STFC, United Kingdom; DOE and NSF, United States of America. Individual groups and members have received support from BCKDF, CANARIE, CRC and DRAC, Canada; PRIMUS 21/SCI/017, CERN-CZ and FORTE, Czech Republic; COST, ERC, ERDF, Horizon 2020, ICSC-NextGenerationEU and Marie Sklodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and MINERVA, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN and NAWA, Poland; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Goran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom. In addition, individual members wish to acknowledge support from CERN: European Organization for Nuclear Research (CERN PJAS); Chile: Agencia Nacional de Investigacion y Desarrollo (FONDECYT 1190886, FONDECYT 1210400, FONDECYT 1230812, FONDECYT 1230987); China: National Natural Science Foundation of China (NSFC-12175119, NSFC 12275265, NSFC-12075060); Czech Republic: Czech Science Foundation (GACR-24-11373 S), Ministry of Education Youth and Sports (FORTE CZ.02.01.01/00/22_008/0004632), PRIMUS Research Programme (PRIMUS/21/SCI/017); European Union: European Research Council (ERC -948254, ERC 101089007), Horizon 2020 Framework Programme (MUCCA -CHIST-ERA-19-XAI-00), Italian Center for High Performance Computing, Big Data and Quantum Computing (ICSC, NextGenerationEU); France: Agence Nationale de la Recherche (ANR-20-CE31-0013, ANR-21-CE31-0013, ANR-21-CE31-0022), Investissements d'Avenir Labex (ANR-11-LABX0012); Germany: Baden-Wurttemberg Stiftung (BW Stiftung-Postdoc Eliteprogramme), Deutsche Forschungsgemeinschaft (DFG-469666862, DFG-CR 312/5-2); Italy: Istituto Nazionale di Fisica Nucleare (ICSC, NextGenerationEU); Japan: Japan Society for the Promotion of Science (JSPS KAKENHI Grant No. 22KK0227, JSPS KAKENHI JP21H05085, JSPS KAKENHI JP22H01227, JSPS KAKENHI JP 22H04944); Netherlands: Netherlands Organisation for Scientific Research (NWO Veni 2020-VI.Veni.202.179); Norway: Research Council of Norway (RCN-314472); Poland: Polish National Agency for Academic Exchange (PPN/PPO/2020/1/00002/U/00001), Polish National Science Centre (NCN 2021/42/E/ST2/00350, NCN OPUS nr 2022/47/B/ST2/03059, NCN UMO-2019/34/E/ST2/00393, UMO-2020/37/B/ST2/01043, UMO-2021/40/C/ST2/00187, UMO-2022/47/O/ST2/00148, UMO-2023/49/B/ST2/04085); Slovenia: Slovenian Research Agency (ARIS grant J1-3010); Spain: Generalitat Valenciana (Artemisa, FEDER, IDIFEDER/2018/048), Ministry of Science and Innovation (MCIN and NextGenEU -PCI2022-135018-2, MICIN and FEDER -PID2021-125273NB, RYC2019-028510-I, RYC2020-030254-I, RYC2021-031273-I, RYC2022-038164-I), PROMETEO and GenT Programmes Generalitat Valenciana (CIDEGENT/2019/023, CIDEGENT/2019/027); Sweden: Swedish Research Council (Swedish Research Council 2023-04654, VR 2018-00482, VR 2022-03845, VR 2022-04683, VR 2023-03403, VR grant 2021-03651), Knut and Alice Wallenberg Foundation (KAW 2018.0157, KAW 2018.0458, KAW 2019.0447, KAW 2022.0358); Switzerland: Swiss National Science Foundation (SNSF-PCEFP2_194658); United Kingdom: Leverhulme Trust (Leverhulme Trust RPG-2020-004), Royal Society (NIF-R1-231091); United States of America: Neubauer Family Foundation.CERN; NDGF (Denmark, Norway, Sweden); KIT/GridKA (Germany); INFN-CNAF (Italy); NL-T1 (Netherlands), PIC (Spain); BNL (USA); ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW; FWF, Austria; ANAS; CNPq; FAPESP, Brazil; NSERC; CFI, Canada; NSFC, China; MEYS CR, Czech Republic; DNRFand DNSRC, Denmark; IN2P3-CNRS; CEA-DRF/IRFU, France; BMBF; MPG, Germany; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT; JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MNiSW, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS; MIZS, Slovenia; MICINN, Spain; Wallenberg Foundation, Sweden; SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taipei; DOE; NSF, United States of America; BCKDF; CANARIE; CRC; DRAC, Canada [PRIMUS 21/SCI/017]; FORTE, Czech Republic; ERC; ERDF; Marie Sklodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex; ANR, France; DFG; AvH Foundation, Germany - EU-ESF; Greek NSRF, Greece; BSF-NSF; NCN [UMO-2019/34/E/ST2/00393, UMO-2020/37/B/ST2/01043, UMO-2021/40/C/ST2/00187, UMO-2022/47/O/ST2/00148, UMO-2023/49/B/ST2/04085]; La Caixa Banking Foundation; CERCA Programme Generalitat de Catalunya; PROMETEO; Generalitat Valenciana, Spain; Goran Gustafssons Stiftelse, Sweden; Royal Society [NIF-R1-231091]; Leverhulme Trust, United Kingdom; CERN: European Organization for Nuclear Research (CERN PJAS); Chile: Agencia Nacional de Investigacion y Desarrollo (FONDECYT) [1190886]; FONDECYT [1230987]; China: National Natural Science Foundation of China [NSFC-12175119, NSFC 12275265, NSFC-12075060]; Czech Republic: Czech Science Foundation [GACR-24-11373 S]; Ministry of Education Youth and Sports [FORTE CZ.02.01.01/00/22_008/0004632]; PRIMUS Research Programme [PRIMUS/21/SCI/017]; European Union: European Research Council [ERC -948254, ERC 101089007, MUCCA -CHIST-ERA-19-XAI-00]; Italian Center for High Performance Computing, Big Data and Quantum Computing (ICSC); France: Agence Nationale de la Recherche [ANR-20-CE31-0013, ANR-21-CE31-0013, ANR-21-CE31-0022]; Investissements d'Avenir Labex; Germany: Baden-Wurttemberg Stiftung; Deutsche Forschungsgemeinschaft [DFG-469666862, DFG-CR 312/5-2]; Japan: Japan Society for the Promotion of Science (JSPS KAKENHI) [22KK0227]; JSPS KAKENHI [JP21H05085, JP22H01227, JP 22H04944, NWO Veni 2020-VI]; Norway: Research Council of Norway [RCN-314472]; Polish National Agency for Academic Exchange [PPN/PPO/2020/1/00002/U/00001]; Polish National Science Centre (NCN) [2021/42/E/ST2/00350]; NCN OPUS [2022/47/B/ST2/03059]; Slovenian Research Agency [J1-3010]; Spain: Generalitat Valenciana; FEDER [PID2021-125273NB, RYC2019-028510-I, RYC2020-030254-I, RYC2021-031273-I, RYC2022-038164-I]; Ministry of Science and Innovation (MCIN) [NextGenEU -PCI2022-135018-2]; GenT Programmes Generalitat Valenciana [CIDEGENT/2019/023, CIDEGENT/2019/027]; Swedish Research Council (Swedish Research Council) [2023-04654, VR 2018-00482, VR 2022-03845, VR 2022-04683, VR 2023-03403, 2021-03651]; Knut and Alice Wallenberg Foundation [KAW 2018.0157, KAW 2018.0458, KAW 2019.0447]; Swiss National Science Foundation [SNSF-PCEFP2_194658]; United Kingdom: Leverhulme Trust (Leverhulme Trust) [RPG-2020-004]; United States of Americ
New Generation Cellular Engineering for Living Therapeutics
No full textThis chapter explores the progress and possibilities of cutting-edge cellular engineering for therapeutic purposes. This statement underscores the fundamental change in medical treatments, moving away from conventional medicines toward living therapeutic systems. It emphasizes the significance of synthetic biology in developing self-replicating systems that have the ability to independently diagnose, treat, and cure diseases. The study focuses on several important topics, including the development of genetic circuits for medical purposes, the use of the human microbiome as a therapeutic platform and its impact on health and disease, the promise of microbiome engineering, and novel approaches for delivering drugs and treating diseases. The chapter also explores the use of biomaterials such as biofilms and biomineralization in treatments, as well as the importance of cross-disciplinary collaboration in the development of therapeutic approaches. The incorporation of these advanced technology offers potential solutions for unfulfilled medical requirements and revolutionizes treatment strategies for a range of illnesses. © 2025 Walter de Gruyter GmbH, Berlin/Boston
Stock Movement Prediction Using Mamba and Ensemble Learning
No full textAnkura; IEEE Computer Society; IEEE Dataport; U.S. National Science Foundation (NSF); Virginia TechThe stock market is influenced by various factors such as national policies, economic conditions, and global events. Accurately predicting stock price changes has long been a critical challenge for investors and economists, as it can significantly reduce investment risks. Accurate forecasts can enhance investment strategies, allowing for maximized returns. However, the volatile and non-linear nature of financial markets makes this task particularly complex. Recently state space models, like Mamba, have shown promising results in sequence modeling. In this work, we apply Mamba to predict the percentage changes in daily stock closing prices. By forecasting these changes, we frame the problem as a classification task, where the goal is to determine whether the stock price will increase or not. By training models with different hyperparameters and combining them through ensemble learning, the prediction accuracy is further improved. To evaluate the model, we analyze stock movements over a series of trading days for six Nasdaq-listed companies. Our model demonstrates notable performance, achieving an average F1 score of 60.5% in predicting the direction of next-day price movement. The model generated an average profit of 10,000. These insights can help investors make more informed decisions, optimizing returns while minimizing risks. © 2024 IEEE