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Discrete Scan Statistics Generated by Dependent Trials and Their Applications in Reliability
(Springer New York, 2024) Eryilmaz,S.; Yalcin,F.; Industrial Engineering
The chapter is concerned with discrete scan statistic based on a sequence of dependent binary trials. In particular, the existing results are reviewed for the distribution of the discrete scan statistic based on a sequence of exchangeable binary trials. The results are discussed in the context of the reliability of the linear consecutive-k-within-m-out-of-n:F system, and a new exact formula for the reliability of the linear consecutive-2-within-m-out-of-n:F system that consists of arbitrarily dependent components is presented. © Springer Science+Business Media, LLC, part of Springer Nature 2024.
Studying the Impact of the “undergraduate Research Projects” Course in Mechatronics Engineering on the Professional Career Development of Engineers
(Rajarambapu Institute Of Technology, 2024) Erden,Z.; Mechatronics Engineering
Undergraduate research (UR) in engineering education is an important active learning strategy, and it is widely used through various implementation styles. Several studies have been conducted to assess the contribution of UR experience in the career path of alumni from an academic point of view and based on graduate studies. This paper is focused on the assessment of UR experience gained through a two-semester long “Undergraduate Research Projects” course sequence, on the professional career of mechatronics engineering alumni. The results of a survey-based investigation show that such UR experience is considered beneficial by the alumni in three main aspects: employment, entrepreneurship and the effect of the obtained knowledge and skills on the professional career. The feedback from the alumni has revealed that this experience contributes significantly to the development of their research abilities. In addition, many graduates emphasized that the UR experience is beneficial for employment as well as for their academic and professional development. The suggestions from the alumni concerning collaboration with the industry, course methodology, and selection of project topics form a basis for systematic UR model development by faculties in the future. © 2024, Rajarambapu Institute Of Technology. All rights reserved.
Cooperation Formation and Progression Among Culturally Adaptive Rational Agents in Prisoner's Dilemma Game Environment
(Institute of Electrical and Electronics Engineers Inc., 2024) Efe,B.; Cerkez,E.; Kilic,H.; Computer Engineering
We investigate whether a persistent and stable cooperative behavior can be observed among particle swarm inspired culturally adaptive and rational players in the context of Prisoner's Dilemma game environment. Our obtained results and discussions point out to the initial value sensitivity of the game set up for cooperation progression as well as soundness of the Prisoner's Dilemma game in the explanation player's behavior. © 2024 IEEE.
Measuring Collective Action Intention Toward Gender Equality Across Cultures
(Hogrefe Publishing GmbH, 2024) Besta,T.; Jurek,P.; Olech,M.; Włodarczyk,A.; Kosakowska-Berezecka,N.; Bosson,J.K.; Zadkowska,M.
Collective action is a powerful tool for social change and is fundamental to women and girls’ empowerment on a societal level. Collective action towards gender equality could be understood as intentional and conscious civic behaviors focused on social transformation, questioning power relations, and promoting gender equality through collective efforts. Various instruments to measure collective action intentions have been developed, but to our knowledge none of the published measures were subject to invariance testing. We introduce the gender equality collective action intention (GECAI) scale and examine its psychometric isomorphism and measurement invariance, using data from 60 countries (N = 31,686). Our findings indicate that partial scalar measurement invariance of the GECAI scale permits conditional comparisons of latent mean GECAI scores across countries. Moreover, this metric psychometric isomorphism of the GECAI means we can interpret scores at the country-level (i.e., as a group attribute) conceptually similar to individual attributes. Therefore, our findings add to the growing body of literature on gender based collective action by introducing a methodologically sound tool to measure collective action intentions towards gender equality across cultures. © 2024 Hogrefe Publishing.
Shocks, Scans, and Reliability Systems
(Springer New York, 2024) Eryilmaz,S.; Industrial Engineering
This chapter summarizes the close connection between one of the widely studied shock models known as δ-shock model and runs/scans. Under discrete time setting, i.e., when the shocks occur according to a binomial process, the linkage between the lifetime of the system under the shock model and the waiting time for the first scan is presented. Such a useful connection may create a new perspective to study the reliability properties of the system under the δ-shock model. © Springer Science+Business Media, LLC, part of Springer Nature 2024.
Systematic Mapping Study on Natural Language Processing for Social Robots
(Prof.Dr. İskender AKKURT, 2024) Adem,A.İ.; Turhan,Ç.; Sezen,A.; Computer Engineering; Software Engineering
Nowadays, social robots are becoming increasingly sophisticated in terms of their ability to interact with humans and possess social skills, and in this context, natural language processing (NLP) plays a critical role for robots to understand and communicate with human language. Natural Language Processing (NLP) is an interdisciplinary field used to help computers understand, interpret, and generate human language with a wide range of applications. The examination of the datasets, methods/techniques and tools, and usage of speech recognition or generation in the fields of NLP is important in understanding the developments in this field. In this study, 35 out of 92 studies in the literature collected from Web of Science were examined using a systematic mapping approach, and important findings on the use of NLP in social robots were identified. In particular, emphasis was placed on the effective evaluation of the research questions in the context of NLP in social robots. This study creates a starting point that will guide research in the field of NLP use in social robots and guide future studies. © 2024, Prof.Dr. İskender AKKURT. All rights reserved.
A Comprehensive Study of the Effect of Scanning Strategy on In939 Fabricated by Powder Bed Fusion-Laser Beam
(Elsevier Editora Ltda, 2024) Doğu,M.N.; Ozer,S.; Yalçın,M.A.; Davut,K.; Obeidi,M.A.; Simsir,C.; Brabazon,D.; Manufacturing Engineering; Metallurgical and Materials Engineering; Department of Metallurgical and Materials Engineering
This study provides a comprehensive investigation into the effects of different scanning strategies on the material properties of IN939 fabricated using the PBF-LB process. The scanning strategies examined included alternating bi-directional scanning with rotation angles of 0°, 45°, 67°, and 90° between adjacent layers (named as shown), as well as alternating chessboard scanning with rotation angles of 67° and 90° (named as Q67° and Q90°). The results revealed that the 45° and 67° samples had the highest relative density, while the 0° and Q67° samples showed the highest average porosity. Moreover, various types of cracks, including solidification, solid-state, and oxide-induced cracks, were observed. Among the bi-directional scan samples, the 0° sample displayed the most extensive cracking and the highest σmax residual stress values in both XZ and XY planes. Conversely, the 45° and 67° samples exhibited fewer cracks. Notably, the lowest σmax residual stress in the XZ planes among the bi-directional scan samples was observed in the 67° sample. Additionally, microstructural analyses indicated differences in grain size and morphology, among the samples. Texture analysis indicated that the 0° and 90° samples exhibited strong cube textures, whereas the texture intensity weakened for the 45° and 67° samples. Moreover, the alternating chessboard scanning strategy led to rougher surfaces (higher Sa and Sz values) compared to the alternating bi-directional scanning strategy, regardless of the rotation angles. Furthermore, the microhardness values among the samples showed minimal variance, ranging between 321 ± 14 HV and 356± 7 HV. © The Authors
Intensive Care Nurses' Knowledge and Practices Regarding Medical Device-Related Pressure Injuries: a Descriptive Cross-Sectional Study
(John Wiley and Sons Inc, 2024) Kurtgöz,A.; Kızıltepe,S.K.; Keskin,H.; Sönmez,M.; Aşatır,İ.; Nursing
This study aims to determine the levels of knowledge and practices of intensive care nurses regarding medical device-related pressure injuries (MDRPIs). This descriptive cross-sectional study was carried out between September 2023 and February 2024, involving 143 nurses working in intensive care units across three hospitals in Türkiye. The data were collected using the demographic form and the Medical Device-related Pressure Injuries Knowledge and Practice Assessment Tool (MDPI-ASSET). Of the nurses, 74.1% have encountered MDRPIs in their unit, 63.6% feel that their knowledge about MDRPIs is insufficient and 90.2% express a desire to receive training about MDRPIs. The participants' total mean MDPI-ASSET score was 11.12 (out of 21). The nurses achieved the highest mean score on the Aetiology/risk factors sub-scale and the lowest mean score on the Staging sub-scale. The analysis revealed significant differences in the mean MDPI-ASSET total scores among nurses based on the status of previous encounters with MDRPIs (t = 2.342; p = 0.021) and their feelings of responsibility for the development of MDRPIs (t = −2.746; p = 0.007). In this study, the knowledge and practices of intensive care nurses regarding medical device-induced pressure injuries were found to be inadequate. Given the frequent occurrence of MDRPIs in intensive care units, it is necessary to support nurses with continuous organizational-level training to improve the quality of care for critically ill patients. © 2024 The Author(s). International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.
A Drop in Serum Progesterone From Oocyte Pick-Up +3 Days To +5 Days in Fresh Blastocyst Transfer, Using Hcg-Trigger and Standard Luteal Support, Is Associated With Lower Ongoing Pregnancy Rates
(Oxford University Press, 2023) Uyanik,E.; Mumusoglu,S.; Polat,M.; Yarali Ozbek,I.; Esteves,S.C.; Humaidan,P.; Yarali,H.; First and Emergency Aid Program
STUDY QUESTION: Do early-and mid-luteal serum progesterone (P4) levels impact ongoing pregnancy rates (OPRs) in fresh blastocyst transfer cycles using standard luteal phase support (LPS)? SUMMARY ANSWER: A drop in serum P4 level from oocyte pick-up (OPU) + 3 days to OPU + 5 days (negative ΔP4) is associated with a ∼2-fold decrease in OPRs. WHAT IS KNOWN ALREADY: In fresh embryo transfer cycles, significant inter-individual variation occurs in serum P4 levels during the luteal phase, possibly due to differences in endogenous P4 production after hCG trigger and/or differences in bioavailability of exogenously administered progesterone (P) via different routes. Although exogenous P may alleviate this drop in serum P4 in fresh transfer cycles, there is a paucity of data exploring the possible impact on reproductive outcomes of a reduction in serum P4 levels. STUDY DESIGN, SIZE, DURATION: Using a prospective cohort study design, following the initial enrollment of 558 consecutive patients, 340 fulfilled the inclusion and exclusion criteria and were included in the final analysis. The inclusion criteria were: (i) female age ≤40 years, (ii) BMI ≤35 kg/m2, (iii) retrieval of ≥3 oocytes irrespective of ovarian reserve, (iv) the use of a GnRH-Agonist or GnRH-Antagonist protocol with recombinant hCG triggering (6500 IU), (v) standard LPS and (vi) fresh blastocyst transfer. The exclusion criteria were: (i) triggering with GnRH-Agonist or GnRH-Agonist plus recombinant hCG (dual trigger), (ii) circulating P4 >1.5 ng/ml on the day of trigger and (iii) cleavage stage embryo transfer. Each patient was included only once. The primary outcome was ongoing pregnancy (OP), as defined by pregnancy ≥12 weeks of gestational age. PARTICIPANTS/MATERIALS, SETTING, METHODS: A GnRH-Agonist (n = 53) or GnRH-Antagonist (n = 287) protocol was used for ovarian stimulation. Vaginal progesterone gel (Crinone, 90 mg, 8%, Merck) once daily was used for LPS. Serum P4 levels were measured in all patients on five occasions: on the day of ovulation trigger, the day of OPU, OPU + 3 days, OPU + 5 days and OPU + 14 days; timing of blood sampling was standardized to be 3-5 h after the morning administration of vaginal progesterone gel. The delta P4 (ΔP4) level was calculated by subtracting the P4 level on the OPU + 3 days from the P4 level on the OPU + 5 days, resulting in either a positive or negative ΔP4. MAIN RESULTS AND THE ROLE OF CHANCE: The median P4 (min-max) on the day of triggering, day of OPU, OPU + 3 days, OPU + 5 days and OPU + 14 days were 0.83 ng/ml (0.18-1.42), 5.81 ng/ml (0.80-22.72), 80.00 ng/ml (22.91-161.05), 85.91 ng/ml (15.66-171.78) and 13.46 ng/ml (0.18-185.00), respectively. Serum P4 levels uniformly increased from the day of OPU to OPU + 3 days in all patients; however, from OPU + 3 days to OPU + 5 days, some patients had a decrease (negative ΔP4; n = 116; 34.1%), whereas others had an increase (positive ΔP4; n = 220; 64.7%), in circulating P4 levels. Although the median (min-max) P4 levels on the day of triggering, the day of OPU, and OPU + 3 days were comparable between the negative ΔP4 and positive ΔP4 groups, patients in the former group had significantly lower P4 levels on OPU + 5 days [69.67 ng/ml (15.66-150.02) versus 100.51 ng/ml (26.41-171.78); P < 0.001] and OPU + 14 days [8.28 ng/ml (0.28-157.00) versus 19.01 ng/ml (0.18-185.00), respectively; P < 0.001]. A drop in P4 level from OPU + 3 days to OPU + 5 days (negative ΔP4) was seen in approximately one-Third of patients and was associated with a significantly lower OPR when compared with positive ΔP4 counterparts [33.6% versus 49.1%, odds ratio (OR); 0.53, 95% CI; 0.33-0.84; P = 0.008]; this decrease in OPR was due to lower initial pregnancy rates rather than increased overall pregnancy loss rates. For negative ΔP4 patients, the magnitude of ΔP4 was a significant predictor of OP (adjusted AUC = 0.65; 95% CI; 0.59-0.71), with an optimum threshold of-8.73 ng/ml, sensitivity and specificity were 48.7% and 79.2%, respectively. BMI (OR; 1.128, 95% CI; 1.064-1.197) was the only significant predictor of having a negative ΔP4; the higher the BMI, the higher the risk of having a negative ΔP4. Among positive ΔP4 patients, the magnitude of ΔP4 was a weak predictor of OP (AUC = 0.56, 95% CI; 0.48-0.64). Logistic regression analysis showed that blastocyst morphology (OR; 5.686, 95% CI; 1.433-22.565; P = 0.013) and ΔP4 (OR; 1.013, 95% CI; 0.1001-1.024; P = 0.031), but not the serum P4 level on OPU + 5 days, were the independent predictors of OP. LIMITATIONS, REASONS FOR CAUTION: The physiological circadian pulsatile secretion of P4 during the mid-luteal phase is a limitation; however, blood sampling was standardized to reduce the impact of timing. WIDER IMPLICATIONS OF THE FINDINGS: Two measurements (OPU + 3 days and OPU + 5 days) of serum P4 may identify those patients with a drop in P4 (approximately one-Third of patients) associated with ∼2-fold lower OPRs. Rescuing these IVF cycles with additional P supplementation or adopting a blastocyst freeze-All policy should be tested in future randomized controlled trials. STUDY FUNDING/COMPETING INTEREST(S): None. S.C.E. declares receipt of unrestricted research grants from Merck and lecture fees from Merck and Med.E.A. P.H. has received unrestricted research grants from MSD and Merck, as well as honoraria for lectures from MSD, Merck, Gedeon-Richter, Theramex, and IBSA. H.Y. declares receipt of honorarium for lectures from Merck, IBSA and research grants from Merck and Ferring. The remaining authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER: The study was registered at clinical trials.gov (NCT04128436). © 2022 The Author(s). Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved.
The Lh Surge and Ovulation Re-Visited: a Systematic Review and Meta-Analysis and Implications for True Natural Cycle Frozen Thawed Embryo Transfer
(Oxford University Press, 2022) Erden,M.; Mumusoglu,S.; Polat,M.; Yarali Ozbek,I.; Esteves,S.C.; Humaidan,P.; Yarali,H.; First and Emergency Aid Program
BACKGROUND: Efficient and safe embryo vitrification techniques have contributed to a marked worldwide increase in the use of elective frozen embryo transfer (FET). Pinpointing the day of ovulation, more commonly by documentation of the LH surge and less commonly by ultrasonography, is crucial for timing of FET in a true natural cycle (t-NC) to maximize the reproductive outcome. OBJECTIVE AND RATIONALE: The definition of the onset of the LH surge should be standardized in t-NC FET cycles; however, a clear definition is lacking in the available literature. The first search question concerns the definition of the onset of the LH surge in a natural cycle. The second search question relates to the duration between the onset of the LH surge and ovulation. SEARCH METHODS: We searched PubMed, Web of Science and Cochrane Library databases for two search questions from inception until 31 August 2021. 'Luteinizing hormone'[MeSH] OR 'LH' AND 'surge' terms were used to identify eligible articles to answer the first question, whereas 'Luteinizing hormone'[MeSH] OR 'LH' AND 'surge' OR 'rise' AND 'ovulation'[MeSH] OR 'follicular rupture' OR 'follicular collapse' were the terms used regarding the second question. The included publications were all written in the English language, conducted in women of reproductive age with regular ovulatory cycles and in whom serial serum or urine LH measurement was performed. For the quality and risk of bias assessment of the included studies, the Strengthening the Reporting of Observational Studies in Epidemiology and modified Newcastle Ottawa Scale were used. OUTCOMES: A total of 10 and 8 studies were included for search Questions 1 and 2, respectively. Over the years, through different studies and set-ups, testing in either serum or urine, different definitions for the onset of the LH surge have been developed without a consensus. An increase in LH level varying from 1.8- to 6-fold above the baseline LH level was used in seven studies and an increase of at least two or three standard deviations above the mean of the preceding LH measurements was used in two studies. An LH level exceeding the 30% of the amplitude (peak-baseline LH level) of the LH surge was defined as the onset day by one study. A marked inter-personal variation in the time interval between the onset of the LH surge and ovulation was seen, ranging from 22 to 56 h. When meta-analysis was performed, the mean duration in hours between the onset of the LH surge and ovulation was 33.91 (95% CI = 30.79-37.03: six studies, 187 cycles). WIDER IMPLICATIONS: The definition of the onset of the LH surge should be precisely defined in future well-designed studies employing state-of-art laboratory and ultrasonographic equipment. The window of implantation in a natural cycle is still a black box, and future research is warranted to delineate the optimal interval to time the embryo transfer in t-NC FET cycles. Randomized controlled trials employing different precise endocrine and/or ultrasonographic criteria for timing of FET in a t-NC are urgently required. © 2022 The Author(s). Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved.
Incidence and Predictors of Permanent Pacemaker Implantation After Transcatheter Aortic Valve Implantation With a Balloon-Expandable Biosprosthesis in Patients With Bicuspid Aortic Valves
(Termedia Publishing House Ltd, 2024) Suygun, Hakan; Kasapkara, Haci Ahmet; Guney, Murat Can; Polat, Melike; Bozkurt, Engin
Introduction:
There are few data on permanent pacemaker implantation (PPMI) in patients who have undergone transcatheter aortic valve implantation (TAVI) for bicuspid aortic valve (BAV) stenosis.

Aim:
The purpose of this study was to evaluate the predictors and incidence of PPMI in bicuspid patients using a balloon-expandable (BE) TAVI device.

Material and methods:
A total of 62 patients with bicuspid morphology who had undergone successful TAVI using a BE device without previous PPMI were included (retrospectively). Their baseline clinical, electrocardiographic (ECG), echocardiographic, and multislice computed tomography (MSCT) details were collected.

Results:
The incidence of PPMI after TAVI in this BAV cohort was 12.9%. All eight patients with PPMs were found to have type 1 left-right (LR) fusion morphology. In univariate analysis, the presence of right bundle branch block (RBBB) in preprocedural ECG ( p < 0.0001), short membraneous septum (MS) evaluated in MSCT ( p < 0.0001), and increased annulus-left main coronary artery distance ( p = 0.02) were statistically significant for PPMI. Among these parameters included in the model using multivariate Firth logistic regression analysis, the presence of preprocedural RBBB ( p = 0.001) and shortness of the MS in MSCT ( p = 0.004) were independent risk factors for predicting postprocedural PPMI in patients who underwent TAVI among those with BAV.

Conclusions:
Preprocedural RBBB on ECG and shorter MS are independent risk factors for PPMI after TAVI in BAV patients and these parameters should be considered before the procedure to guide clinical decision making. Type 1 LR patients may be considered at increased risk of PPMI.
Fluorescent and Electrochemical Detection of Nuclease Activity Associated With streptococcus Pneumoniae Using Specific Oligonucleotide Probes
(Royal Soc Chemistry, 2024) Goikoetxea, Garazi; Akhtar, Khadija-Tul Kubra; Prysiazhniuk, Alona; Borsa, Baris A.; Aldag, Mehmet Ersoy; Kavruk, Murat; Hernandez, Frank J.; Nutrition and Dietetics
Streptococcus pneumoniae (S. pneumoniae) represents a significant pathogenic threat, often responsible for community-acquired pneumonia with potentially life-threatening consequences if left untreated. This underscores the pressing clinical need for rapid and accurate detection of this harmful bacteria. In this study, we report the screening and discovery of a novel biomarker for S. pneumoniae detection. We used S. pneumoniae nucleases as biomarker and we have identified a specific oligonucleotide that works as substrate. This biomarker relies on a specific nuclease activity found on the bacterial membrane, forming the basis for the development of both fluorescence and electrochemical biosensors. We observed an exceptionally high sensitivity in the performance of the electrochemical biosensor, detecting as low as 10(2) CFU mL(-1), whereas the fluorescence sensor demonstrated comparatively lower efficiency, with a detection limit of 10(6) CFU mL(-1). Moreover, the specificity studies have demonstrated the biosensors' remarkable capacity to identify S. pneumoniae from other pathogenic bacteria. Significantly, both biosensors have demonstrated the ability to identify S. pneumoniae cultured from clinical samples, providing compelling evidence of the potential clinical utility of this innovative detection system.
Review of Modern Forest Fire Detection Techniques: Innovations in Image Processing and Deep Learning
(Mdpi, 2024) Ozel, Berk; Alam, Muhammad Shahab; Khan, Muhammad Umer; Mechatronics Engineering
Fire detection and extinguishing systems are critical for safeguarding lives and minimizing property damage. These systems are especially vital in combating forest fires. In recent years, several forest fires have set records for their size, duration, and level of destruction. Traditional fire detection methods, such as smoke and heat sensors, have limitations, prompting the development of innovative approaches using advanced technologies. Utilizing image processing, computer vision, and deep learning algorithms, we can now detect fires with exceptional accuracy and respond promptly to mitigate their impact. In this article, we conduct a comprehensive review of articles from 2013 to 2023, exploring how these technologies are applied in fire detection and extinguishing. We delve into modern techniques enabling real-time analysis of the visual data captured by cameras or satellites, facilitating the detection of smoke, flames, and other fire-related cues. Furthermore, we explore the utilization of deep learning and machine learning in training intelligent algorithms to recognize fire patterns and features. Through a comprehensive examination of current research and development, this review aims to provide insights into the potential and future directions of fire detection and extinguishing using image processing, computer vision, and deep learning.
Advancing Mmwave Altimetry for Unmanned Aerial Systems: a Signal Processing Framework for Optimized Waveform Design
(Mdpi, 2024) Awan, Maaz Ali; Dalveren, Yaser; Kara, Ali; Derawi, Mohammad; Department of Electrical & Electronics Engineering
This research advances millimeter-wave (mmWave) altimetry for unmanned aerial systems (UASs) by optimizing performance metrics within the constraints of inexpensive automotive radars. Leveraging the software-defined architecture, this study encompasses the intricacies of frequency modulated continuous waveform (FMCW) design for three distinct stages of UAS flight: cruise, landing approach, and touchdown within a signal processing framework. Angle of arrival (AoA) estimation, traditionally employed in terrain mapping applications, is largely unexplored for UAS radar altimeters (RAs). Time-division multiplexing multiple input-multiple output (TDM-MIMO) is an efficient method for enhancing angular resolution without compromising the size, weight, and power (SWaP) characteristics. Accordingly, this work argues the potential of AoA estimation using TDM-MIMO to augment situational awareness in challenging landing scenarios. To this end, two corner cases comprising landing a small-sized drone on a platform in the middle of a water body are included. Likewise, for the touchdown stage, an improvised rendition of zoom fast Fourier transform (ZFFT) is investigated to achieve millimeter (mm)-level range accuracy. Aptly, it is proposed that a mm-level accurate RA may be exploited as a software redundancy for the critical weight-on-wheels (WoW) system in fixed-wing commercial UASs. Each stage is simulated as a radar scenario using the specifications of automotive radar operating in the 77-81 GHz band to optimize waveform design, setting the stage for field verification. This article addresses challenges arising from radial velocity due to UAS descent rates and terrain variation through theoretical and mathematical approaches for characterization and mandatory compensation. While constant false alarm rate (CFAR) algorithms have been reported for ground detection, a comparison of their variants within the scope UAS altimetry is limited. This study appraises popular CFAR variants to achieve optimized ground detection performance. The authors advocate for dedicated minimum operational performance standards (MOPS) for UAS RAs. Lastly, this body of work identifies potential challenges, proposes solutions, and outlines future research directions.
Spatial Effectiveness in High-Rise Timber Towers: a Global Perspective
(Mdpi, 2024) Ilgin, Huseyin Emre; Aslantamer, Ozlem Nur; Interior Architecture and Environmental Design
High-rise timber structures signify a rising trend, thanks to their significant environmental and economic advantages that occur over their complete lifespan. Enhancing spatial effectiveness in these structures is a critical design consideration for project feasibility. Currently, there has been no comprehensive study on the space efficiency of such towers. This article analyzed 79 cases all over the world to deepen the knowledge of design features shaping spatial efficiency. The critical findings are as follows: (1) the most common architectural preferences include residential function, a centrally located service core, and prismatic arrangements; (2) the preferred structural material is composite, while a shear walled frame system is the favored structural system; (3) the average spatial efficiency and percentage of core area to GFA were recorded at 84% and 10%, ranging from the lowest values of 70% and 4% to the highest values of 95% and 21%, respectively; and (4) no significant differences were detected in the effect of core design approaches on spatial effectiveness if appropriately planned, with similar inferences drawn concerning form and the structural material used. This article will assist in developing design directions for different interested parties, including architectural designers taking part in the advancement of high-rise timber towers.
Space Efficiency of Tall Buildings in Singapore
(Mdpi, 2024) Aslantamer, Ozlem Nur; Ilgin, Hueseyin Emre; Interior Architecture and Environmental Design
Space efficiency in Singaporean tall buildings results from a complex interplay of historical, architectural, engineering, technological, socioeconomic, and environmental factors. The city-state's innovative and adaptive approach has enabled it to overcome the challenges associated with skyscraper construction, leading to the development of some of the most advanced and sustainable high-rise structures in the world. However, there is currently a lack of detailed analysis on space utilization in Singaporean high-rise buildings. This study addresses this gap by examining 63 cases. The main findings of this research: 1. Residential functions, central core layouts, and prismatic shapes are the most frequent. 2. Concrete material with a shear-walled frame system is the preferred structural choice. 3. Average spatial efficiency is 80%, and the core-to-GFA (Gross Floor Area) ratio averages 17%. These metrics vary from a minimum of 68% and 5% to a maximum of 91% and 32%, respectively. These insights offer valuable guidance for Singaporean construction professionals, particularly architects, helping them make informed design decisions for high-rise projects.
Optimized Porous Carbon Particles From Sucrose and Their Polyethyleneimine Modifications for Enhanced Co₂ Capture
(Mdpi, 2024) Ari, Betul; Inger, Erk; Sunol, Aydin K.; Sahiner, Nurettin; Airframe and Powerplant Maintenance
Carbon dioxide (CO2), one of the primary greenhouse gases, plays a key role in global warming and is one of the culprits in the climate change crisis. Therefore, the use of appropriate CO2 capture and storage technologies is of significant importance for the future of planet Earth due to atmospheric, climate, and environmental concerns. A cleaner and more sustainable approach to CO2 capture and storage using porous materials, membranes, and amine-based sorbents could offer excellent possibilities. Here, sucrose-derived porous carbon particles (PCPs) were synthesized as adsorbents for CO2 capture. Next, these PCPs were modified with branched- and linear-polyethyleneimine (B-PEI and L-PEI) as B-PEI-PCP and L-PEI-PCP, respectively. These PCPs and their PEI-modified forms were then used to prepare metal nanoparticles such as Co, Cu, and Ni in situ as M@PCP and M@L/B-PEI-PCP (M: Ni, Co, and Cu). The presence of PEI on the PCP surface enables new amine functional groups, known for high CO2 capture ability. The presence of metal nanoparticles in the structure may be used as a catalyst to convert the captured CO2 into useful products, e.g., fuels or other chemical compounds, at high temperatures. It was found that B-PEI-PCP has a larger surface area and higher CO2 capture capacity with a surface area of 32.84 m(2)/g and a CO2 capture capacity of 1.05 mmol CO2/g adsorbent compared to L-PEI-PCP. Amongst metal-nanoparticle-embedded PEI-PCPs (M@PEI-PCPs, M: Ni, Co, Cu), Ni@L-PEI-PCP was found to have higher CO2 capture capacity, 0.81 mmol CO2/g adsorbent, and a surface area of 225 m(2)/g. These data are significant as they will steer future studies for the conversion of captured CO2 into useful fuels/chemicals.
Partner Phubbing and Sleep Quality: Serial Mediation Models With Relationship Satisfaction and Perceived Stress
(Sage Publications inc, 2024) Dikdere, Busra; Turkarslan, Kutlu Kagan; Department of Psychology
The increasing integration of technology into our lives has been affecting our daily routines and even our sleeps. Being a relatively new concept, phubbing refers to the act of overly engaging with one's phone while dismissing those around in the social settings. In this context, partner phubbing involves individuals exhibiting this neglect in the presence of their romantic partners. Evidence suggests that higher partner phubbing may lead to lower relationship satisfaction and higher perceived stress. The aim of the present cross-sectional study was to examine whether relationship satisfaction and perceived stress mediate the relationship between partner phubbing and sleep quality. Four hundred twenty-three individuals (females = 78.5%, M-age = 29.19, SD = 6.87) participated in the study and completed the measures of partner phubbing, relationship satisfaction, perceived stress, and sleep quality. The results of the serial mediation analyses showed that partner phubbing was not a direct predictor of sleep quality. However, the relationship between partner phubbing and sleep quality was mediated by the four indirect paths through relationship satisfaction (beta = 0.04, p < .05), perceived stress (beta = 0.09, p < .05), relationship satisfaction-perceived stress (beta = 0.02, p < .05), and perceived stress-relationship satisfaction (beta = 0.00, p < .05). The findings suggest that partner phubbing may diminish sleep quality by reducing relationship satisfaction and increasing perceived stress levels. Alternatively, perceived stress exacerbated by partner phubbing could reduce relationship satisfaction, which eventually worsens sleep quality. Digital detox programs, group interventions, emotion-focused couple interventions, and stress management training can help overcome the effects of partner phubbing on sleep quality.
Reevaluation of Plate-Fin Heatsink Natural Convection Correlations for Sideways and Three-Dimensional Inclinations
(Taylor & Francis inc, 2024) Mehrtash, Mehdi; Energy Systems Engineering
The common orientations of the plate-fin heat sink for natural convection cooling of electronics are vertical and upward-facing horizontal. However, depending on various use scenarios, the heat sink may be inclined, intentionally or otherwise. In our previous papers concerning this subject, the author proposed a set of correlations for plate-fin heat sinks covering all inclination angles backward and forward (pitch rotation) from the vertical position of the heat sink. The set was based on a series of computational simulations with a validated model. At the time, tilting the heat sink sideways (roll rotation) was not considered. In the present study, though, the sideways inclination of the plate-fin heat sinks is simulated using our previous model only by adjusting the direction of the gravitational acceleration vector, thus requiring no additional validation. It is determined that the previously proposed correlation is valid up to 80 degrees sideways inclinations of the heat sink. Interesting flow structures are observed when the heat sink is tilted 90 degrees sideways. Furthermore, it is demonstrated that the correlation surprisingly remains valid if the heat sink is simultaneously rotated in both axes (pitch and roll).
Chronic Pregabalin Treatment Reduced Anxiety, and Acute Pregabalin Treatment Increased Depression-Like Behaviors in Rats
(Bmc, 2024) Caliskan, Hasan; Akat, Firat; Dursun, Ali Dogan; Zaloglu, Nezahet; Basic Sciences
BackgroundPregabalin is an antiepileptic drug that binds to the alpha-2/delta unit at presynaptic voltage-dependent calcium channels. We aimed to investigate the effect of acute and chronic pregabalin administration on anxiety and depression-like behaviors.MethodsFifty-six male Wistar albino rats were divided into seven groups: control, vehicle, and five different dose groups (5, 10, 30, 60, and 100 mg/kg). Pregabalin was administered for two weeks. Depression-like behaviors were evaluated by Forced swimming test. Anxiety-like behavior (ALB) was evaluated by Open field test (OFT), Elevated Plus Maze (EPM), and light-dark box. Subjects underwent the forced swimming test (FST) after the first dose, while the open field test (OFT), elevated plus maze (EPM), and light-dark box (LDB) were performed after two weeks of treatment. Further sucrose preference test was conducted to evaluate anhedonia until the end of the experiment.ResultsIn the forced swimming test, depression-like behaviors increased after acute single-dose administration of 10, 30, 60, 100 mg/kg pregabalin. According to OFT results, chronic 100 mg/kg pregabalin showed anxiolytic effects by decreasing grooming, and freezing behaviors. In addition, 100 mg/kg chronic pregabalin administration significantly increased the time spent in the central region, the number of entries to the center, and the unsupported rearing number without causing any change in locomotor activity. According to EPM results, both chronic 60 and 100 mg/kg pregabalin treatments showed anxiolytic effects by increasing open arm time and head dipping behavior. In addition, 60 and 100 mg/kg chronic pregabalin administration significantly decreased stretch attend posture. All pregabalin administrations between 5 and 100 mg/kg displayed anxiolytic effects in the LDB. Sucrose preference was above 65% for the duration of all experiments and subjects did not show anhedonia.ConclusionAcute pregabalin treatment triggered depression-like behaviors. Anhedonia, which may be associated with depression, was not observed during chronic treatment. Moreover, chronic treatment with pregabalin revealed potent anxiolytic effects in different behavior patterns and doses for all tests of unconditional anxiety. In particular, 100 mg/kg chronic pregabalin administration decreased anxiety-like behaviors in all experiment setups. Although the anxiolytic effect was demonstrated in chronic treatment, acute treatment of pregabalin induced depression-like behaviors, and thus in clinical practice should be done with caution, especially in patients with anxiety-depression comorbidity.

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