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Photoelectrochemical and Catalytic Hydrogen Generation From Hydrolysis of Nabh4 Using Ruthenium and Platinum Decorated Zno/Tio2 Heterojunction Thin Film Electrodes
No full textIn this study, the use of ruthenium (Ru) and platinum (Pt)-decorated zinc oxide-titanium oxide (ZnO/TiO2) nanostructured catalysts for catalytic and photoelectrochemical (PEC) sodium borohydride (NaBH4) hydrolysis for hydrogen production was investigated. Catalytic studies of ZnO/TiO2/Ru-Pt electrodes conducted under dark conditions have shown that the hydrolysis process does not depend on the structure of the catalyst. In contrast to the dark catalytic measurements, it was found that the morphology of the nanocatalyst and the metal used to sensitize the nanocatalyst affected the PEC performance. From the BET analysis, ZnO nano-flower (NF) structures have a surface area of 80 m2g−1, while the surface area of nanosheet (NS) structures is calculated as 17 m2g−1. In parallel with their high surface area, ZnO NF structures were found to have higher optical absorption in the UV and visible region than NS structures. However, the high photosensitivity of NS structures compared to the NF enabled them to exhibit very good PEC performance, especially at high NaBH4 concentrations. In this study, the highest applied bias photoconversion efficiency was observed in ZnO NS/TiO2/Ru catalysts with 9.0%. This very high efficiency indicates the enormous potential of this catalyst for next-generation green hydrogen production. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.Belarusian Republican Foundation for Fundamental Research, BRFFR, (T19TYuB-004); Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK, (119M030
Observations on Nist Sp 800-90b Entropy Estimators (Jan, 10.1007/S12095-025-00778-7, 2025)
No full text
Correction: [Trust Region-Based Efficient Global Optimization for Aircraft Wing Design in a Multidisciplinary Design Optimization Framework] (American Institute of Aeronautics and Astronautics Inc, AIAA)
No full textCorrection Notice Acknowledgement The authors gratefully acknowledge the support provided by The Scientific and Technological Research Council of Türkiye (TUBITAK), under award 2224-A. © 2025 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved
Observations on Nist Sp 800-90b Entropy Estimators
No full textRandom numbers play a crucial role in cryptography since the security of cryptographic protocols relies on the assumption of the availability of uniformly distributed and unpredictable random numbers to generate secret keys, nonce, salt, etc. However, real-world random number generators sometimes fail and produce outputs with low entropy, leading to security vulnerabilities. The NIST Special Publication (SP) 800-90 series provides guidelines and recommendations for generating random numbers for cryptographic applications and describes 10 black-box entropy estimation methods. This paper evaluates the effectiveness and limitations of the SP 800-90 methods by exploring the accuracy of these estimators using simulated random numbers with known entropy, investigating the correlation between entropy estimates, and studying the impacts of deterministic transformations on the estimators. © The Author(s) 2025.Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTA
Inferior Medial Genicular Artery Based Tibia Osteocutaneous Flap: Anatomic Study and Clinical Application for Small Composite Digital Defects
No full textReconstruction of composite digital defects presents challenges, as it requires short-pedicled, small flap. In this report, the authors present a new vascularized bone graft based on the inferior medial genicular artery (IMGA) harvested from the proximal medial tibia with overlying skin. The purpose of this study was to investigate the feasibility of this new flap for small composite tissue defects in digits. Methods: This cadaveric dissection study involved 6 fresh frozen cadaver lower extremities and surgical techniques. We recorded the length and diameter of the pedicle. Between October 2023 and February 2024, 9 patients who had small composite tissue defects in digits, metacarpal, and metatarsal bones were treated using this new free flap. The average follow-up period was 9.6 (7-11) months. The Michigan hand outcomes questionnaire (MHQ) scale was used to evaluate postoperative outcomes. Results: Owing to the consistent anatomy of IMGA from cadaveric study, 7 osteocutaneous and 2 bone-only flaps were used to reconstruct the small composite tissue defects. In clinical cases, the average diameter of the artery of the pedicle was 1.2 +/- 0.22 mm. The average pedicle length was 2.5 +/- 0.31 cm. Skin island dimensions ranged from 1 x 2 cm2 to 2 x 4 cm2. Bone flap sizes ranged between 1 x 2 x 1 cm3 and 1 x 4 x 1 cm3. Except for 1 patient, all the flaps survived. In all the patients, bony union was achieved within 2 months postoperatively. The average MHQ score was 75.95 +/- 9.52. No severe donor site morbidity occurred. Scar hypersensitivity in donor site was recorded in 2 patients. Conclusion: This is the first description of IMGA-based tibia osteocutaneous flap and this technique can be another tool for reconstructive surgeons. (c) 2025 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies
Enhancing Inflammatory Bowel Disease Care: the Role of Mobile Applications in Disease Management
No full textMulti-Target Integrated Sensing and Communications in Massive Mimo Systems
No full textBjornson, Emil/0000-0002-5954-434X; Topal, Ozan Alp/0000-0002-4640-7020Integrated sensing and communications (ISAC) allows networks to perform sensing alongside data transmission. While most ISAC studies focus on single-target, multi-user scenarios, multi-target sensing is scarcely researched. This letter examines the monostatic sensing performance of a multi-target massive MIMO system, aiming to minimize the sum of Cram ; eacute;r-Rao lower bounds (CRLBs) for target direction-of-arrival estimates while meeting user equipment (UE) rate requirements. We propose several precoding schemes, comparing sensing performance and complexity, and find that sensing-focused precoding with power allocation for communication achieves near-optimal performance with 20 times less complexity than joint precoding. Additionally, time-sharing between communication and sensing outperforms simple time division, highlighting the benefits of resource-sharing for ISAC.This work was supported in part by the Swedish funding agency Vinnova through Celtic-Next Project RAI-6Green, and in part by SSF SUCCESS Project.Swedish funding agency Vinnova through Celtic-Next Project RAI-6Green; SSF SUCCESS Projec
Rispecnet: a Geometry Independent Deep Learning Oriented Method for Coherent and Non-Coherent Signal Number Estimation
No full textIn this study, "the total number of non-coherent signals including only direct-path signals" and "the total number of coherent signals including direct-path and multi-path signals" estimation algorithm tailored for sensor array signal processing systems is proposed. The applications of these algorithms are numerous. Existing Direction Finding (DF) techniques often face challenges related to the rank loss of the noise-free covariance matrix due to uncertainties regarding the number of direct-paths and multi-paths. Traditional and modified spatial smoothing algorithms have opened up possibilities for estimating coherent signals' Direction of Arrival (DoA). However, all these algorithms need to know the exact number of coherent and non-coherent signal numbers in the presence of interference. Besides, they can work properly only if a very specific antenna array geometry is provided. Many existing signal enumeration methods fail when distinguishing coherent and non-coherent signal numbers in an environment where a multi-path effect may exist. In this paper, a novel deep learning-based method which is called Received Individual Sensor Powers and Eigenvalues Combination Network (RISPECNet) is proposed to make this distinction, with the addition of existing information that is already calculated by the covariance matrix in prevailing methods. Compared with conventional approaches for distinguishing coherent signals, the necessity for Forward Backward Spatial Smoothing (FBSS) is eliminated, resulting in lower mathematical complexity that can be utilized in real-time applications. Additionally, the proposed algorithm works on various geometries by using networks specifically trained for the relevant geometry to make it possible to realize it using sensors without being bound to a specific sensor geometry. It is tested on simulated and also real-world data in non-coherent only scenarios and coherent and non-coherent scenarios together. Simulation results show that the proposed method has an enhanced estimation capability in lower and higher SNR Levels. For real world data sets which includes only non-coherent signals, as the SNR rises from 3 dB to 18 dB, RISPECNet's accuracy improves significantly, ranging from 95.1% to 99.7%, surpassing the performance of nearly all other methods. On the other hand, for simulated dataset which consists of coherent and non-coherent signals, the proposed architecture's accuracy values increases from 93.7% to 98.1% when the SNR increases from 0 dB to 40 dB. So, RISPECNet outperforms the existing methods in terms of accuracy without the need for FBSS
Iloprost-Loaded Electrospun Polycaprolactone/Gelatin Membranes for Enhanced Healing of Colon Anastomosis
No full textDespite the variety of proposed solutions, anastomotic leakage is still a critical complication after colorectal surgery, which causes increased clinical mortality and morbidity. By enhancing microcirculation in the colonic mucosa, the use of Iloprost (Ilo) has shown promising results for the healing of anastomosis. The purpose of this study is to examine the performance of Ilo-impregnated Polycaprolactone:Gelatin electrospun membranes (PCL/Gel/Ilo) on anastomosis repair and intra-abdominal adhesion behavior in the Rat colon. Wistar Albino rats were randomly divided into four groups: sham, Control (only resection-anastomosis), PCL/Gel, and PCL/Gel /Ilo (n = 12 for each). On the seventh day after colon anastomosis, a second laparotomy was conducted. During this procedure, intra-abdominal adhesion was examined, and the anastomotic segment was removed for burst pressure and histological evaluation. There was no statistically significant difference in intra-abdominal adhesions and major complications between the electrospun membrane groups and the control group. The membrane-applied groups exhibited significantly higher anastomotic burst pressure than the control group irrespective of their Ilo content. In terms of neovascularization and muscle necrosis, membrane-applied groups demonstrated statistically significant improvements over the control group. Furthermore, the PCL/Gel/Ilo applied group showed enhanced neovascularization and lower muscular necrosis; however, statistically significant differences were not observed compared to the PCL/Gel applied group. Compared to the control group, the application of electrospun PCL/Gel and PCL/Gel/Ilo membranes resulted in safe and effective healing of colon anastomosis. The fact that Ilo application cannot be distinguished from the regular membrane group necessitates additional research into the doped fibrous mat and its application method.T.C. Minister of Health University of Health Sciences Ankara Training and Research Hospital Medical Specialty Education BoardThe authors are grateful to T.C. Minister of Health University of Health Sciences Ankara Training and Research Hospital