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Articles 631 - 660 of 67361
Full-Text Articles in Entire DC Network
Sex Differences In The Association Of Vascular Risk And Apoe Genotype With Cognitive Decline And Dementia: Evidence From A U.S. Longitudinal Study, Longjian Liu, Jintong Hou, Saishi Cui, Xiaopeng Zhao, Zuolu Liu, J. Craig Longenecker, Nathalie S May, Jin Jun Luo, Rose Ann Dimaria-Ghalili, Howard J. Eisen
Sex Differences In The Association Of Vascular Risk And Apoe Genotype With Cognitive Decline And Dementia: Evidence From A U.S. Longitudinal Study, Longjian Liu, Jintong Hou, Saishi Cui, Xiaopeng Zhao, Zuolu Liu, J. Craig Longenecker, Nathalie S May, Jin Jun Luo, Rose Ann Dimaria-Ghalili, Howard J. Eisen
Division of Cardiology Faculty Papers
BACKGROUND: Sex differences in the association between vascular factors and cognitive outcomes remain unclear. We aimed to investigate the associations of blood pressure metrics (hypertension, systolic blood pressure [SBP), pulse pressure, ankle and brachial pressures, and ankle to brachial pressure index [ABI]) with the risk of cognitive decline and dementia.
METHODS: We conducted a population-based longitudinal analysis using data from the Atherosclerosis Risk in Communities (ARIC) study (begun in 1987-1989) in the United States. We analyzed a total of 12,268 participants aged 45-64 years who had validated exposure measurements, cognitive function tests (first administrated 1990-1992), and followed up for incidence …
Classifying Glaucoma Disease Images Via Deep Neural Network Technique, Maysoon Jaaffar Rahim, Ali Abid Dawood Al-Zuky, Fatin Ezzat Muhy Al-Dean Al-Obaidi
Classifying Glaucoma Disease Images Via Deep Neural Network Technique, Maysoon Jaaffar Rahim, Ali Abid Dawood Al-Zuky, Fatin Ezzat Muhy Al-Dean Al-Obaidi
Baghdad Science Journal
A class of eye diseases known as glaucoma refers to a category of eye disease which is often associated with increased intraocular pressure, and can damage the eye by destroying nerve cells in the retina in addition to the eye's optic nerve. The accuracy of diagnosing glaucoma eye disease depends on the knowledge and experience of the ophthalmologist. Therefore, the need for automatic feature extraction from the retinal image is crucial for the diagnosis of glaucoma eye disease. The current article introduces a multi-layer deep neural network model with convolution and classification layers. The originality of the current search focuses …
Psychological Responses To Interval And Continuous Exercise In People Living With Hiv: A Single-Blind, Counterbalanced, Crossover Study., Phelipe Wilde, Victor S. De Queiros, Jason R. Jaggers, Angelo Sabag, Julio M. Alves, Elaine Fernandes, Robert F.C. Rocha, Paulo F. De Almeida-Neto, Ronaldo Vagner Thomatieli-Santos, Paulo Moreira Silva Dantas
Psychological Responses To Interval And Continuous Exercise In People Living With Hiv: A Single-Blind, Counterbalanced, Crossover Study., Phelipe Wilde, Victor S. De Queiros, Jason R. Jaggers, Angelo Sabag, Julio M. Alves, Elaine Fernandes, Robert F.C. Rocha, Paulo F. De Almeida-Neto, Ronaldo Vagner Thomatieli-Santos, Paulo Moreira Silva Dantas
Faculty and Staff Scholarship
Abstract
Aim: This study compared acute psychological responses to a single session of low-volume high-intensity interval exercise (HIIE-LV), high-volume highintensity interval exercise (HIIE-HV), and moderate-intensity continuous exercise (MICE) in people living with HIV, and healthy controls using a randomized, counterbalanced crossover design. Methods: The participants (people living with HIV, and healthy controls) completed three exercise sessions in randomized order: HIIE-HV (4 4 min at 80% of maximal power output [Wmax]), HIIE-LV (10 60 s at 90% Wmax), and MICE (30 min at 60% Wmax). Psychological outcomes included affective response assessed by the Feeling Scale, exercise enjoyment and future exercise intention …
Comprehensive Study For Characterization Of Blending And Heat Treatment Of Organic-Based Polymer Thin Films, Ruaa M. Ali, Atyaf H. Kazem, Khalidah G. Hasan
Comprehensive Study For Characterization Of Blending And Heat Treatment Of Organic-Based Polymer Thin Films, Ruaa M. Ali, Atyaf H. Kazem, Khalidah G. Hasan
Baghdad Science Journal
Thin films of Polypyrrole (PPy)/Cupper Phthalocyanine (CuPc) have been prepared by the spin coating technique on glass substrates, Samples were prepared in a blending ratio (50:50) in addition to pure PPy and CuPc at room temperature, these samples were annealed at (473K) and then characterized by X ray diffraction (XRD), Energy Dispersive Spectroscopy (EDX) and Scanning electron microscopy (FESEM) at different magnifications power. XRD patterns reveal that pure polypyr role is amorphous. A wide peak was seen at roughly 2θ= 24° with an average crystallite size of roughly 56 nm and CuPc had a polycrystalline structure. Annealing results …
Using Physics-Informed Neural Networks For Solving 2Nd-Order Volterra Integro-Differential Equation By Deepxde Library, Oday Ahmed Jasim, Abdulghafor M. Al-Rozbayani
Using Physics-Informed Neural Networks For Solving 2Nd-Order Volterra Integro-Differential Equation By Deepxde Library, Oday Ahmed Jasim, Abdulghafor M. Al-Rozbayani
Baghdad Science Journal
Many disciplines widely use deep learning (DL) as a key tool for investigating the behavior of various systems. Deep learning (DL) has recently been utilized to solve differential equations using physics-based input. Physics-informed neural networks (PINNs) are a novel DL model that excels at solving both inverse and forward non-linear PDE problems. PINNs may be trained as surrogate models for approximation solutions to the VIDE without label data by embedding the physical information outlined by PDEs in feedforward NNs. The objective of this study is to solve the second-order Volterra integral-differential equations (2nd-order VIDEs) for the first time using PINN …
Hybrid Pre-Trained Models With Machine Learning Classifier For Skin Cancer Classification, Toqa A. Sadoon, Asaad F. Qasim, Mohammed Khalaf, Ali M. Hasan
Hybrid Pre-Trained Models With Machine Learning Classifier For Skin Cancer Classification, Toqa A. Sadoon, Asaad F. Qasim, Mohammed Khalaf, Ali M. Hasan
Baghdad Science Journal
Classification of skin lesions can be challenging because of the subtle variation on the skin surface due to the appearance of these lesions. In the other hand, the digital dermoscopy has been widely used by dermatologist to diagnose cancer. For accurate detection, the clinicians should have a lot of experiences, but human nature is prone to error, forgetfulness, tension, and speed in diagnosis, all of which can affect the accuracy of detection. For these reasons, automated skin lesion classification has been used by many researchers to help dermatologists in making the right and accurate decision during diagnosis. A preprocessing image …
Allfromair™ Ires (Gen 3) – System Architecture, Process Physics & Compliance Verification, Vesa Olavi Lius
Allfromair™ Ires (Gen 3) – System Architecture, Process Physics & Compliance Verification, Vesa Olavi Lius
Defensive Publications Series
This disclosure describes the ALLFROMAIR™ IRES (Gen 3), a unified thermodynamic platform integrating heating, cooling, ventilation, and atmospheric water generation (AWG) into a single hardware unit. The system utilizes an ”Anticubic” U-channel geometry with airflow velocities <2.5 m/s to minimize fan power according to the Cube Law. Key innovations include a ”Three-Stage Rocket” thermodynamic process and a ”Turbo Effect” where regenerative pre-cooling reduces compressor temperature lift (\Delta T \approx 5K), enabling practical COPs >30.
The disclosure specifically details a pressure-modulated spray nozzle matrix capable of switching between ”Flash Evaporation” (<300 µm droplets) and ”Film Wetting” modes to maximize latent heat transfer on Heresite P-413/Hydrophilic coated exchangers. The system solves historical displacement ventilation stratification (”The Bahco Problem”) via a scavenger heat exchanger (HX4) coupled to a hydronic floor loop. An integrated ”Water Ring” harvests and purifies condensate to EU Directive 2020/2184 standards, enabling decentralized potable water production for residential, commercial, and tropical applications.
Keywords:
Integrated Regenerative Energy System (IRES), ALLFROMAIR, Anticubic U-Channel, Low Lift Heat Pump, Atmospheric Water Generator (AWG), Pressure Modulated Spray Matrix, Flash Evaporation, Thermodynamic Up-Gearing, Heresite P-413, Hydrophilic Topcoat, Radiant-Assisted Displacement Ventilation, Twin-Leg Air Separation, EU Directive 2020/2184, Three-Stage Rocket Process.
Rack Thermal Topography Gans, N/A
Rack Thermal Topography Gans, N/A
Defensive Publications Series
The technology relates to a framework for designing the thermal layout of compute resource racks to proactively mitigate heat concentration zones and optimize cooling efficiency. The framework utilizes an artificial intelligence (AI) model, specifically a generative adversarial network (GAN), to automate the layout design process. The generative network is configured to ingest physical and operational constraints and produce a simulated layout. The initial layout estimation is then verified by a discriminator network, which acts as a neural network approximation of fluid dynamics, providing a closed-loop feedback mechanism to refine the generated result. The framework allows for the exploration of a …
Carbon Nanotubes Enhanced Tio2/G-C3N4 As A Potential Nanocomposite Material For Impedance-Type Humidity Sensors, Mohamed Morsy
Carbon Nanotubes Enhanced Tio2/G-C3N4 As A Potential Nanocomposite Material For Impedance-Type Humidity Sensors, Mohamed Morsy
HBRC Journal
The development of high-performance humidity sensors based on nanotechnology has become critical for different applications. This work focuses on the fabrication and characterization of impedance-type humidity sensors based on graphitic carbon nitride, titanium dioxide, and carbon nanotubes. The prepared materials comprise g-C3N4, g-C3N4/TiO2, and g-C3N4/TiO2/CNTs, which have been synthesized through the co-precipitation method. The properties of the nanocomposites have been verified through different characterization techniques that confirm the phase composition and morphology. The humidity-sensing response of the prepared materials was tested within a humidity range of 11%–97% RH at different testing frequencies. The unique structure of …
A Generalized Convolutional Autoencoder Framework For Seismic Waveform Compression, Emad B. Helal, Mostafa M. Ibrahim, Ali G. Hafez
A Generalized Convolutional Autoencoder Framework For Seismic Waveform Compression, Emad B. Helal, Mostafa M. Ibrahim, Ali G. Hafez
Almaaqal Journal of Sustainability and Emerging Technology
Effective data compression methods have become crucial as the amounts of seismic data are growing exponentially. Due to extensive surveys and ongoing real-time monitoring, compression not only reduces storage requirements but also optimizes communication bandwidth between remote seismic stations and central processing hubs. In this paper, a generalized autoencoder-based compression framework is proposed.. Its primary innovation is a single, fixed network architecture that delivers robust performance across low, medium, and high compression ratios (CRs). Performance was compared with a dynamic pooling-based model and three wavelet-based methods (db4, sym8, coif3) across CRs from 2 to 100. Experimental results demonstrate that the …
A Review Of Machine Learning Methods In Energy Management System, Mays Sattar Al-Fatllah, Zaipatimah Ali, Aidil Azwin Zainul Abidin
A Review Of Machine Learning Methods In Energy Management System, Mays Sattar Al-Fatllah, Zaipatimah Ali, Aidil Azwin Zainul Abidin
Almaaqal Journal of Sustainability and Emerging Technology
Traditional energy sources are vital for energizing residences and industries. Nonetheless, they meet considerable obstacles, such as deteriorating infrastructure, ecological decline, resource exhaustion, price fluctuations, and a disparity between real-time demand and supply. Conversely, renewable energy sources offer cleaner and more sustainable energy sources. Renewable energy mitigates the pollution caused by carbon and greenhouse gas emissions in traditional power systems. Incorporating renewable energy into a power system needs an efficient management system to keep stability and improve power use. Modern energy management systems (EMS) face a significant challenge in controlling renewable and non-renewable energy sources. The challenges encompass intermittent and …
Multivariate Optimization Of Nonlinear Response Functions Using Central Composite Design, Hussein M. Hussein, Bassma H. Elwakil, Esraa Abdelhamid Moneer, Sara H. Akl, Yahya H. Shahin
Multivariate Optimization Of Nonlinear Response Functions Using Central Composite Design, Hussein M. Hussein, Bassma H. Elwakil, Esraa Abdelhamid Moneer, Sara H. Akl, Yahya H. Shahin
Almaaqal Journal of Sustainability and Emerging Technology
This study addresses critical challenges in multivariate optimization by: (1) developing efficient strategies for optimizing nonlinear response functions in high-dimensional parameter spaces, (2) quantifying comparative performance of traditional versus statistical design methodologies, (3) establishing mathematical frameworks for parameter interactions, and (4) validating results through comprehensive statistical analysis. A dual-phase optimization framework combined One-Variable-At-a-Time (OVAT) screening with Central Composite Design-based Response Surface Methodology (CCD-RSM). Five parameters were evaluated using rotatable CCD (α= 2.378) with 50 design points. Statistical analysis included analysis of variance (ANOVA), regression modeling, interaction quantification, and cross-validation. CCD-RSM demonstrated superior performance with model predictability improving from …
Machine Learning Framework For Automatic Classification Of Nano-Seismic Signals Preceding Earthquakes, Ghada Ali, Ali G. Hafez, Sayed Hasaneen, Hamed Nofel, Nabeel Al-Atwan, Ahmed Mohamed
Machine Learning Framework For Automatic Classification Of Nano-Seismic Signals Preceding Earthquakes, Ghada Ali, Ali G. Hafez, Sayed Hasaneen, Hamed Nofel, Nabeel Al-Atwan, Ahmed Mohamed
Almaaqal Journal of Sustainability and Emerging Technology
Nano-seismicity preceding earthquakes has many applications in fault prediction, in structure health monitoring, and in enhancing fault and source parameter determination. Not all earthquakes are preceded by these precursors; therefore, there is a need to identify P-wave arrivals that are preceded by these nano signals, which will eliminate errors in P-wave arrival timing. The current work introduces topologies capable of automatically categorizing the arrivals with nano-seismic precursors. The proposed methods are trained on datasets extracted from stations belonging to Egyptian National Seismic Network (ENSN). These records contain both P-wave arrivals preceded by such nano precursors and other records without these …
Optimizing Bioethanol Production Using Design Of Experiments For Sustainable Biofuel Development, Hussein M. Hussein, Yahya H. Shahin, Ihab A. Moneam
Optimizing Bioethanol Production Using Design Of Experiments For Sustainable Biofuel Development, Hussein M. Hussein, Yahya H. Shahin, Ihab A. Moneam
Almaaqal Journal of Sustainability and Emerging Technology
This study presents a statistically optimal approach for bioethanol production from sugarcane bagasse (SCB) using alkaline pretreatment, enzymatic hydrolysis, and fermentation processes. To maximize cellulose yield, four extraction parameters—solvent type, concentration, temperature, and time—were optimized using a Taguchi statistical model. The Taguchi-optimized extraction yields 11.3% increased cellulose recovery relative to cellulose recovered via non-optimized extraction methods (i.e., alkaline treatment with 6% NaOH at 90 °C for 3 hours). This yielded 45.20% cellulose (w/w), with 37.80% weight loss (predicted weight loss was 36.94%). Statistical analysis of extraction results verified solvent type (p = 0.0022) and temperature (p = 0.0007) to be …
A Smart City Transformation Survey: Using Intelligent Buildings To Promote Smart Cities, Salma A. Alhashimi, Majid A. Alwan, Ali N. Aliedani
A Smart City Transformation Survey: Using Intelligent Buildings To Promote Smart Cities, Salma A. Alhashimi, Majid A. Alwan, Ali N. Aliedani
Almaaqal Journal of Sustainability and Emerging Technology
The challenges of urbanization have been greatly aided by the integration of cutting-edge technology into smart buildings and cities. In smart cities and buildings, machine learning and the Internet of Things are essential for boosting sustainability, increasing safety, and optimizing resource use. In order to enable more effective, connected, and comfortable living in urban settings, this work has introduced the relationship between creative technology and buildings. It also discusses the regulatory frameworks for smart cities and emphasizes the importance of standardization in this regard.
Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee
Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee
Turkish Journal of Chemistry
Paclitaxel (Pac) is an important anticancer bioactive compound, and the availability of an accurate and robust analytical method for its quantification is of utmost importance. In this investigation, a novel, direct, and reliable spectrophotometric method has been proposed for the estimation of Pac via a complex formation reaction with osmium (Os). The method was based on the reaction of Pac with Os tetroxide, which produced a yellowish-brown complex. The resulting complex is soluble in water and displays a maximum absorption peak at 482 nm. The reaction conditions, including reactant concentration, pH, temperature, and reaction time, were optimized to obtain the …
Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh
Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh
Turkish Journal of Chemistry
Hydrazone chemistry has become important and plays a key role in the development of organic compounds. Hydrazones can be useful pharmacophores for creating novel derivatives, owing to their broad range of activities. In this study, a series of N-((2-hydroxy-3-(2-(substitutedbenzylidene)hydrazine-1-carbonyl)naphthalen-1-yl)(3-nitro-phenyl/3,4-dimethoxyphenyl)methyl)acetamide derivatives were prepared, characterized by FTIR, 1H-NMR, 13C-NMR, and mass spectroscopy, and evaluated for their antimicrobial, antiinflammatory, and antioxidant activities along with in silico studies. The substituted derivatives were synthesized by the reaction of acetonitrile, chlorosulphonic acid, and substituted benzaldehyde with the hydrazones. The antimicrobial evaluation showed that compound 3i had more antimicrobial potential than the other tested molecules. Compound 3j …
Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman
Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman
Turkish Journal of Chemistry
In this work, electrochemical biosensors utilizing tyrosinase (Tyr) for the detection of the nonselective beta-adrenergic agonist isoproterenol (ISO) are presented. Three different configurations for immobilizing Tyr on a graphite electrode (GE) are compared: (1) GE modified with poly(diallyldimethylammonium chloride) (PDADMAC), PDADMAC/Tyr/GE; (2) PDADMAC combined with iridium nanoparticles (IrNPs) in a stepwise preparation, resulting in PDADMAC/IrNPs/Tyr/GE; and (3) a composite of PDADMAC and IrNPs mixed with Tyr at a 1:1 (v:v), forming PDADMAC/(IrNPs-Tyr)/GE. Surface morphology was characterized using scanning electron microscopy (SEM). Cyclic voltammetry (CV) and amperometry were applied to characterize the biosensor’s performance. Within the linear range of 5 μM …
Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Turkish Journal of Chemistry
This study used single-crystal X-ray diffraction, elemental analysis, infrared (IR) spectroscopy, theoretical nuclear magnetic resonance (NMR), and theoretical ultraviolet spectroscopy to characterize 3 newly synthesized crystalline compounds. Additionally, the nonlinear optical, highest occupied molecular orbital energies, lowest occupied molecular orbital energies, band gap, molecular electrostatic potential, and thermodynamic parameters of the 3 crystalline compounds were examined. The strong correlation between experimental IR spectra and theoretical NMR chemical shifts confirmed the accuracy of computational predictions. The molecular formulas of the 3 newly synthesized crystalline compounds, each containing different ligand molecules, were: C8H14O4·2(C6H4N2), C5H7N2·NCS, and Ni(CN)4·2(C5H7N2)·2(H2O) for compounds 1, 2, and 3, …
New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş
New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş
Turkish Journal of Chemistry
A series of novel bis-piperazine derivatives (2a–2f) were synthesized and structurally characterized via Fourier transform-infrared and nuclear magnetic resonance spectroscopic techniques. Their gamma-ray shielding efficiencies were investigated through simulations on the Monte Carlo-based Geant4-GATE platform, and the results were benchmarked against data obtained from the XCOM and Phy-X software. A simulation model incorporating an NaI scintillation detector and a point gamma source was developed. Key shielding parameters, including mass attenuation coefficient, linear attenuation coefficient, half-value layer, and mean free path (MFP), were evaluated at gamma energies of 80, 120, 662, 1173, and 1332 keV. Additionally, the energy absorption buildup factor …
Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere
Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere
Turkish Journal of Chemistry
Gold is abundant in nature, however, precise and reliable analytical methods for its detection are required stemming from its increasing prevalence in environmental, biological, and industrial systems, as well as the growing interest in understanding its function in living organisms and its effects on human health. This study investigates the use of biogenically synthesized silver nanoparticles (AgNPs) for the preconcentration and determination of gold ions prior to determination by UV-Vis spectrophotometry. AgNPs were synthesized by reducing silver nitrate through the use of an apricot kernel extract as both reducer and stabilizer agent. The colloidal yellowish AgNPs interacted with gold ions, …
Structural Categorization And Identification Of Electrostatic Interactions In Two Proposed Human Serum Albumin Dimerization Patterns And Dipyridamole Interaction, Haluk Çeti̇nok, Veyi̇s Karakoç, Erol Erçağ, Yusuf Meli̇h Şekerer, Hasan Demi̇rci̇
Structural Categorization And Identification Of Electrostatic Interactions In Two Proposed Human Serum Albumin Dimerization Patterns And Dipyridamole Interaction, Haluk Çeti̇nok, Veyi̇s Karakoç, Erol Erçağ, Yusuf Meli̇h Şekerer, Hasan Demi̇rci̇
Turkish Journal of Chemistry
Human serum albumin (HSA) is a ubiquitous, multifunctional protein responsible for the systemic distribution of both endogenous metabolites and exogenous pharmaceuticals. Its inherent properties, particularly its ability to seep into tissues and its multiple ligand-binding sites, have rendered HSA an attractive vehicle for nanoparticle-based drug delivery systems, particularly for cancer targeting. In this study, we present high-resolution crystallographic data revealing two distinct dimerization patterns of HSA (Protein Data Bank [PDB] ID: 9V61) obtained under high-concentration crystallization conditions, along with results from dipyridamole docking. Both dimer types demonstrate extensive interface areas and a significant number of electrostatic interactions. Comparative analysis with …
Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy
Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy
Turkish Journal of Chemistry
Novel coumarin–triazole–coumarin dyads were synthesized and characterized, and their α-glycosidase inhibitory activities were evaluated spectrophotometrically. Compound 4e exhibited the most pronounced inhibitory effect, with an IC50 value of 38.98 ± 0.77 μM. The IC50 values for 4d and 4a were 93.55 ± 1.70 μM and 95.04 ± 3.55 μM, respectively. The Lineweaver–Burk plot showed that 4e inhibited α-glycosidase in a mixed type. In addition, the Ki value obtained from the Dixon plot was 19.95 ± 0.15 μM for α-glycosidase.
Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz
Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz
Turkish Journal of Chemistry
This study investigates the extraction behavior of Y³⁺ ions using a Multi-Dropped Liquid Membrane (MDLM) system that employs di(2-ethylhexyl) phosphoric acid (D₂EHPA) as the carrier ligand. The focus is on the system’s ability to transport ions between aqueous phases selectively. The extracted complex was analyzed spectrophotometrically via ultraviolet–visible (UV–Vis) measurements after complexation with 0.05% Arsenazo III. The aim of this study was to determine the influence of the optimum D₂EHPA carrier concentration, together with the pH and temperature conditions of the donor and acceptor phases, on the system’s extraction performance. Accordingly, a series of extraction experiments was performed at different …
Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay
Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay
Turkish Journal of Chemistry
The direct synthesis of boron nitride nanotubes (BNNTs) via chemical vapor deposition (CVD) in high-temperature furnaces remains highly challenging due to difficulties in optimizing key experimental parameters such as synthesis temperature and catalyst composition. These challenges often result in uncontrolled growth behavior, adversely affecting the quality and yield of the BNNTs. In this study, colemanite was effectively utilized as a boron source for the high-yield synthesis of directionally aligned BNNTs. The synthesis was carried out using a CVD method that used a dual-catalyst system comprising Fe2O3 and MgO in conjunction with a silicon carbide template under high-temperature conditions. The resulting …
Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat
Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat
Turkish Journal of Chemistry
This study highlights the potential of organometallic carbonyl complexes as selective markers for biomolecules, enabling sensitive infrared (IR) detection. The regio- and stereoselective coupling of N-acetylhistamine, a histidine analogue, with the precursor complex 1 [Fe(CO)₃(1,4-η⁵-N-pyridiniocyclohexa-1,3-diene)] BF₄ affords the labeled complex 3 [Fe(CO)₃(1,4-η⁵-N-acetylhistaminocyclohexa-1,3-diene)]. X-ray diffraction (XRD) confirms the exo stereochemistry and reveals a rigid, well-defined architecture. IR and 1H nuclear magnetic resonance spectroscopic studies combined with IR-monitored acid–base titration demonstrate the complex’s stability in aqueous media between pH 5 and 8, alongside a modest increase in basicity relative to the free ligand. These findings establish the Fe(CO)₃ moiety as a robust …
Table Of Contents, The Editors
A Method For Advance Detection Of Underground Concealed Water Hazards In Coal Mines Based On Borehole Transient Electromagnetic Method And Vector Synthesis, Fan Tao, Hao Yue, Li Ping, Zhao Rui, Liu Zaibin, Ma Liang, Li Peng, Yan Junsheng
A Method For Advance Detection Of Underground Concealed Water Hazards In Coal Mines Based On Borehole Transient Electromagnetic Method And Vector Synthesis, Fan Tao, Hao Yue, Li Ping, Zhao Rui, Liu Zaibin, Ma Liang, Li Peng, Yan Junsheng
Coal Geology & Exploration
Background The advance detection of underground concealed water hazards in coal mines is crucial to ensuring the safe and efficient roadway tunneling. The borehole transient electromagnetic (TEM) method allows for long-distance advance detection. However, due to the limitation of the spatial structure of boreholes, currently available techniques can only effectively identify low-resistivity anomalies (e.g., water-bearing structures) in the radial direction, leaving blind areas in the primary tunneling direction (i.e., the axial direction of boreholes). Objective and Method To address this challenge, this study proposed a method for the advance detection of concealed water hazards in the axial direction of boreholes …
Fructure Mechanisms And Fracture Distribution Patterns Of Main Roofs In Goaves Within Abandoned Mines, Tao Xuefeng, Shi Biming, Hua Xinzhu, Lin Baiquan, Yue Jiwei, Liang Yuehui, Zhang Chengcheng, Qin Hao, Yang Yong, Xue Yonglin
Fructure Mechanisms And Fracture Distribution Patterns Of Main Roofs In Goaves Within Abandoned Mines, Tao Xuefeng, Shi Biming, Hua Xinzhu, Lin Baiquan, Yue Jiwei, Liang Yuehui, Zhang Chengcheng, Qin Hao, Yang Yong, Xue Yonglin
Coal Geology & Exploration
Objective In abandoned mines, the storage zones of free gas are closely associated with overburden fractures in goaves. To accurately estimate free gas resources in abandoned mines, it is necessary to thoroughly investigate the rupture mechanisms of blocks in main roofs in goaves, as well as the overburden fractures and rupture trace morphologies in goaves. Methods Based on the masonry beam theory, this study established a mechanical model for the primary cantilever beam of a main roof. The analytical solutions of the stress components in the primary cantilever beam were analyzed using the stress inverse method, and the mathematical expression …