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Improve Thermal Sensing Drones for Emergency Response: A Comprehensive Control System Approach
Full text linkUnmanned aerial systems equipped with thermal imaging cameras are vital for effective emergency response, especially in firefighting scenarios. These drones require high stability, rapid responsiveness, and precise positioning, all of which depend on advanced control systems. This study introduces an innovative approach using an Interval Genetic Algorithm to optimize Proportional-Integral-Derivative (PID) and H2 controllers, enhancing the performance of thermal imaging drones for emergency response and surveillance applications. A comprehensive mathematical model was developed to simulate quadcopter dynamics in both " + " and "X" configurations. The challenges of PID tuning and the limitations of H2 controllers in real-world environments were addressed, resulting in improved drone stability and control under demanding conditions. The results demonstrate a significant enhancement in altitude control and motor speed stabilization, with an average increase of 20% in control precision and a 15% reduction in system response time compared to traditional control methods. These findings advance drone technology by providing more reliable and efficient tools for emergency responders
Chemical modification-induced enhancements in quantum dot photovoltaics: a theoretical and molecular descriptive analysis
No full textFunding agency : Taif University
Grant number : TU-DSPP- 2024 - 76The study reports a molecular descriptive based design for carbon quantum dots (CQDT) to their photovoltaic (PV) performance. Taking C30H14 as an example, its new molecular systems as CQDT1-CQDT5 are optimized by Density Functional Theory (DFT). Their molecular descriptors are calculated with the help of a Python programming language package RDKit tool. Their Frontier Molecular Orbitals (FMOs) show a charge switching behavior, and UV–Vis analysis shows a redshift of their maximum absorption (λmax) values. Among their RDKit descriptors, their Bertz Complexity Topology (BertzCT) and molecular connectivity indices (χov) emerge as important for determining their Jsc. Pmax shows positive relation correlation. Further efficiency is analyzed through additional PV parameters while their electronic excitations are visualized using Multiwfn-based Transition Density Matrix (TDM) and electron–hole overlap analysis. This synergy of theoretical and molecular descriptor-related approaches could pave the way for the rational design of high-efficiency CQDTs as PV devices
Evaluating the Antibiofilm Effects of Antibiotics on Staphylococcus Species from Pediatric Hematology-Oncology Patients
No full textBiofilms are microbial communities and occur on different medical devices such as catheters. The formation of bacterial biofilms on medical devices leads to indwelling medical device-related infections. Since biofilm bacteria are more resistant to antibiotics than planktonic bacteria, using these antibiotics in indwelling medical device-related infections causes recurrence of infections, treatment failure, and death. Minimum inhibitory concentration (MIC) is an important reference in treating acute infections caused by planktonic bacteria. However, MIC is ineffective in indwelling medical device-related infections caused by biofilm bacteria. The study aims to demonstrate the necessity and development of effective and standard methods such as minimum biofilm prevention concentration, minimum biofilm inhibitory concentration, and minimum biofilm eradication concentration in the case of indwelling medical device-related infection. The study was conducted with 10 isolates of Staphylococcus species from patients who developed infections in the Pediatric Hematology-Oncology Department at Medical Park Bahcelievler Hospital. According to the study results, even if planktonic bacteria are sensitive to antibiotics, they can become resistant to this antibiotic when they are in a biofilm (p < 0.05, Crosstab). Also, inhibiting the growth of planktonic bacteria does not prevent biofilm formation. The study additionally revealed that inhibiting and eradicating biofilm is more difficult than preventing biofilm formation (p < 0.05)
Day 4 Versus Day 5 Fresh Embryo Transfer in In Vitro Fertilization: Is It All About Timing?
Full text linkObjective: Most studies concentrate on comparisons between the cleavage stage and blastocyst stage of embryos during in vitro stimulation treatment. We aimed, in this study, to compare the pregnancy rates of day 4 or day 5 blastocyst transfers, all derived from fresh, antagonist-regulated in vitro fertilization (IVF) cycles, and to evaluate the factors affecting pregnancy success. Methods: This retrospective cohort study evaluated 3681 fresh embryo transfer cycles conducted at a private IVF center between 2019 and 2021. Patients were divided into two groups based on the day of embryo transfer: day 4 (Group 1) and day 5 (Group 2). Subgroup analyses were performed according to age (≤40 vs. >40 years) and the number of oocytes retrieved (≤4 vs. >4). All patients underwent ovarian stimulation with FSH alone or in combination with hMG, and GnRH antagonist protocols were used for pituitary suppression. Final oocyte maturation was triggered with recombinant hCG, and fertilization was achieved via intracytoplasmic sperm injection (ICSI) for all cases. Embryos were cultured in sequential media and assessed daily until transfer on day 4 or day 5, based on embryo morphology and clinic logistics. Results: Pregnancy was more likely among women under 40 than among women over 40. There were a total of 1217 women who underwent day 4 transfer and 2464 women who underwent day 5 transfer. A total of 660 (54.2%) of the women transferred on day 4 developed pregnancy. Among those transferred on day 5, 1610 (65.3%) developed pregnancy. When compared to the 4th day, a single embryo transfer on the 5th day enhances pregnancy success by 1.8 times, while two embryo transfers raise it by 1.6 times. Furthermore, when the number of oocytes is greater than four and the number of embryos transferred is two, the pregnancy success rate is 2.5 times higher when embryo transfer is performed on the fifth day versus the fourth day. Regardless of age, oocyte count, or number of embryos transferred, 5th-day fresh embryo transfers enhanced pregnancy success by 1.9 times compared to 4th-day transfer. Conclusions: Transfers of fresh embryos on day 5 are superior to those on day 4 and should be favored, especially for people over the age of 40, regardless of the number of embryos transferred, even if that individual has fewer than four oocytes
Microsurgical resection of a midbrain cavernous malformation via the paramedian supracerebellar infratentorial trans-lateral mesencephalic sulcus approach using the dynamic lateral semi-sitting position: 2-dimensional operative video with 3D anatomical models
No full textBrainstem cavernous malformations are relatively rare lesions with a higher tendency of hemorrhage than supratentorial cavernous malformations. Due to the compact arrangement of fiber tracts and nuclei of the region, any hemorrhagic event can cause severe neurological deficits. This eloquent architecture of the area also makes any surgical attempt challenging. Anatomical location and dimension of the lesion, presence of hemorrhage, age, and the neurological status of the patient need to be considered before determining the appropriate course of treatment. A surgical approach is preferred for young symptomatic patients with at least 1 previous episode of bleeding. Subtemporal and supracerebellar infratentorial approaches can be used to access these lesions.1-5 We present a 44-year-old woman with a hemorrhagic tegmental cavernous malformation presenting with imbalance and right-sided hemiparesis (Video 1). The paramedian supracerebellar infratentorial translateral mesencephalic sulcus approach is used to resect the lesion with the patient in a dynamic lateral semisitting position. The paramedian variant of the supracerebellar infratentorial approach provides a relatively bridging vein-free corridor compared with midline approaches.6 With the patient in the semisitting position, gravity retraction of the brain provided a natural corridor with a clear surgical field. In the dynamic lateral semisitting position, we aimed to reduce the risk of venous air embolism associated with the sitting position by keeping the patient in the lateral decubitus position during the dural and extradural phases of the surgery
A Novel Flip-Filtered Orthagonal Frequency Division Multiplexing-Based Visible Light Communication System: Peak-to-Average-Power Ratio Assessment and System Performance Improvement
No full textFiltered orthogonal frequency division multiplexing (F-OFDM), employed in visible light communication (VLC) systems, has been considered a promising technique for overcoming OFDM’s large out-of-band emissions and thus reducing bandwidth efficiency. However, due to Hermitian symmetry (HS) imposition, a challenge in VLC involves increasing power consumption and doubling inverse fast Fourier transform IFFT/FFT length. This paper introduces the non-Hermitian symmetry (NHS) Flip-F-OFDM technique to enhance bandwidth efficiency, reduce the peak–average-power ratio (PAPR), and lower system complexity. Compared to the traditional HS-based Flip-F-OFDM method, the proposed method achieves around 50% reduced system complexity and prevents the PAPR from increasing. Therefore, the proposed method offers more resource-saving and power efficiency than traditional Flip-F-OFDM. Then, the proposed scheme is assessed with HS-free Flip-OFDM, asymmetrically clipped optical (ACO)-OFDM, and direct-current bias optical (DCO)-OFDM. Concerning bandwidth efficiency, the proposed method shows better spectral efficiency than HS-free Flip-OFDM, ACO-OFDM, and DCO-OFDM. © 2025 by the authors
Recent advances of structure, function, and engineering of carboxylesterases for the pharmaceutical industry: A minireview
No full textCarboxylesterases have a wide range of applications due to their catalytic efficiency, robust structure, and broad substrate specificity. These enzymes, which can hydrolyze carboxylic acid esters, amides, and thioesters, stand out with their regio- and enantioselective properties. They play a crucial role in synthesizing pharmaceutical intermediates, including secondary and tertiary alcohols, α-hydroxy acids, and various bioactive compounds. However, in some cases, the enantioselectivity of carboxylesterases may be insufficient to achieve conversions with the purity required by the pharmaceutical industry. This review summarizes the crucial role of carboxylesterases, particularly in the pharmaceutical field, focusing on the classification, structure, and engineering approaches. After introducing the main families of carboxylesterases, the structural studies are presented to give a comprehensive insight into the active site architecture and related key determinants for enantioselectivity. The protein engineering studies to improve the enantioselectivity of carboxylesterases are discussed along with solvent engineering and immobilization applications
Human vs machine: The future of decision-making in plastic and reconstructive surgery
No full textBackground: Artificial intelligence (AI)-driven technologies offer transformative potential in plastic surgery, spanning pre-operative planning, surgical procedures, and post-operative care, with the promise of improved patient outcomes.
Objectives: To compare the web-based ChatGPT-4o (omni; OpenAI, San Francisco, CA) and Gemini Advanced (Alphabet Inc., Mountain View, CA), focusing on their data upload feature and examining outcomes before and after exposure to CME articles, particularly regarding their efficacy relative to human participants.
Methods: Participants and LLMs completed 22 multiple-choice questions to assess baseline knowledge of CME topics. Initially, both LLMs and participants answered without article access. In incognito mode, the LLMs repeated the tests over 6 days. After accessing the articles, responses from both LLMs and participants were extracted and analyzed.
Results: There was a significant increase in mean scores after the article was read in the resident group, indicating a significant rise. In the LLM groups, the ChatGPT-4.o (omni) group showed no significant difference between pre- and post-article scores, but the Gemini Advanced group demonstrated a significant increase. It can be stated that the ChatGPT-4.o and Gemini Advanced groups have higher accuracy means compared to the resident group in both pre and post-article periods.
Conclusions: The analysis between human participants and LLMs indicates promising implications for the incorporation of LLMs in medical education. As these models increase in sophistication, they offer the potential to serve as supplementary tools within traditional learning environments. This could aid in bridging the gap between theoretical knowledge and practical implementation
A COMPARISON OF THE EFFICACY OF DIFFERENT REMINERALIZATION AGENTS: AN IN VITRO STUDY
No full textPurpose: The objective of this study was to evaluate and compare the remineralizing efficacy of a solution containing silver diamine fluoride (SDF) with agents containing sodium fluoride (NaF) and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on artificial caries lesions using laser fluorescence (DIAGNODent) and micro-computed tomography (-CT). Methods: Artificial caries lesions were created on extracted primary incisors without any lesions or defects in the enamel tissue. The teeth were randomly divided into four groups (n = 8): Group 1: SDF (Advantage Arrest, Elevate Oral Care, USA); Group 2: NaF (Clinpro, 3M ESPE, USA); Group 3: CPP-ACP (GC Tooth Mousse, Recaldent, USA); Group 4: control. After applying remineralization agents, the samples were kept in an artificial saliva solution and measured by DIAGNODent at regular intervals. When the remineralization process was complete, enamel surfaces were analyzed by-CT for mineral density, lesion depth, and area using the computer program. Data obtained were statistically analyzed. Results: In the comparison of DIAGNODent values between the groups, a statistically significant difference was found between the values measured on the fourteenth day (p-value=0.003). A significant difference was found between the mineral density (g/cm3) values measured by-CT on the fourteenth day after remineralization according to the groups (p-value=0.001). Conclusions: All agents used in this study provided remineralization. The DIAGNODent and-CT measurements demonstrated that the SDF group had a higher remineralization value than the other groups. Considering the ease of use as well as its effectiveness, it is thought that the SDF solution can be used successfully to arrest early childhood caries. SDF application positively influences enamel remineralization
Performance analysis of input power variations in high data rate DWDM-FSO systems under various rain conditions
No full textThis paper investigates the performance of a 32-channel Dense Wavelength Division Multiplexing Free-Space Optical (DWDM-FSO) system under various rain conditions and transmission distances ranging from 5 to 20 km. The study aims to identify optimal input power levels across different rain scenarios (-10 dBm, -5 dBm, 0 dBm, 5 dBm, and 10 dBm) to enhance the reliability and efficiency of optical communication in adverse weather. Findings indicate that for light rain conditions, input power levels of -10 dBm are suitable for distances up to 15 km. In moderate rain scenarios, -5 dBm is optimal for reliable communication up to 10 km, while higher input powers of 5 dBm are necessary to maintain performance in heavy rain conditions beyond 5 km. This study highlights the critical relationship between input power and atmospheric conditions, confirming that higher power levels can effectively mitigate the effects of rain-induced attenuation and scattering. Key parameters such as transmitter and receiver configurations, atmospheric attenuation, scattering, and turbulence were analyzed, demonstrating the importance of selecting appropriate power levels to ensure successful data transmission. Additionally, the research suggests future explorations into adaptive modulation techniques and quantum applications to further enhance system resilience and performance. The results provide valuable insights for system designers, enabling the adaptation of FSO systems to meet the challenges posed by varying environmental conditions and guiding developments in robust optical communication technologies