Study Of Dynamics Research Articles

CADD based designing and biological evaluation of novel triazole based thiazolidinedione coumarin hybrids as antidiabetic agent.

A series of 5-(substituted benzylidene) thiazolidine-2,4-dione and coumarin hybrids (I-1 to I-16) were designed and synthesized to explore key structural requirements for effective α-glucosidase inhibitors. Molecular docking studies were conducted to investigate their interactions with various targets, including DPP-4, α-glucosidase, α-amylase, and PPAR-γ. The docking scores and binding energies indicated that Compound I-1 emerged as the optimal scaffold for drug design, excluding α-amylase. Compound I-1 was synthesized based on the insights gained from molecular docking and simulations, which helped predict interactions and identify critical structural features. Pharmacokinetic properties were evaluated through drug-likeness and ADMET studies. Additionally, density functional theory (DFT) analyses were performed to assess the stability and reactivity of potential diabetes mellitus drug candidates. Dynamic simulation studies further elucidated the stability and interaction dynamics of the top-ranked compound I-1. In vitro evaluation against the α-glucosidase enzyme yielded an IC50 value of 1.49µg/ml. In vivo studies demonstrated that Compound I-1 significantly reduced blood glucose levels, with values of 94.15mg/dL and 74.60mg/dL at doses of 10mg/kg and 20mg/kg, respectively. Furthermore, Compound I-1, like Acarbose, resulted in significant reductions in ALT, AST, ALP, urea, LDH, and creatinine levels, suggesting improved liver and kidney function.

Optimizing Urban Ventilation in Heritage Settings: A Computational Fluid Dynamics and Field Study in Zhao’an Old Town, Fujian

This study investigates the optimization of urban ventilation in Zhao’an Old Town, Fujian, through the integration of Computational Fluid Dynamics (CFD) simulations and field measurements. The findings underscore the critical roles of spatial layout indicators, such as the Frontal Area Index (FAI), Opening-to-Facade Ratio (OFR), and Building Volume Density (BVD), in influencing wind flow and thermal performance. The FAI was identified as the most influential factor in shaping airflow, while the OFR and BVD highlighted the importance of open spaces and balanced building density for natural ventilation and thermal comfort. Practical strategies, such as optimizing building orientations, increasing facade permeability, and leveraging natural cooling elements like the Dongxi River, are proposed to address ventilation challenges while preserving the town’s cultural and historical integrity. Unlike previous studies, this research combines CFD simulations with summer field measurements to provide a highly accurate and contextually relevant evaluation of wind flow dynamics in compact urban environments. By systematically analyzing the interplay between urban morphology and ventilation efficiency, this study offers actionable recommendations for improving outdoor comfort in heritage settings. The outcomes serve as a valuable reference for sustainable urban planning, contributing to the development of strategies that balance environmental performance with the preservation of Zhao’an Old Town’s unique cultural heritage.

Molecular dynamics study of the dissolution of crystalline and amorphous nickel nanoparticles in aluminium

Abstract The dissolution of a nickel nanoparticle in aluminium under the conditions of the crystalline and amorphous state of aluminium and nickel, which can be achieved, in particular, with severe plastic deformation of the powders of the initial mixture (mechanoactivation), was studied by means of molecular dynamics. It is shown that the state of the aluminium structure (crystalline or amorphous) has a relatively small effect on the intensity of mutual diffusion of Ni and Al up to the melting temperature of aluminium. This is due to the formation of a crystalline aluminium layer around the crystalline particle, which repeats the Ni lattice. In the case of the amorphous state of the nickel particle and the aluminium matrix, dissolution occurred much faster than in the crystalline state of nickel. That is, mutual diffusion occurs significantly more strongly in the case of the amorphous state of nickel compared to the case of amorphous aluminium at the same constant temperature. The diameter of the nickel nanoparticle in the considered range from 4 to 12 nm did not affect the temperature at which the mutual diffusion of Ni and Al sharply accelerated with varying temperature. This was due to the fact that the melting point of aluminium did not change when simulating particles of different sizes.

Vibrational Excitation in Gas-Surface Collisions of CO with Au(111): A First-Principles Nonadiabatic Dynamics Study

Vibrational Excitation in Gas-Surface Collisions of CO with Au(111): A First-Principles Nonadiabatic Dynamics Study

Multiphoton dissociation dynamics of molecular oxygen O2 via two-photon resonant Rydberg states in the UV region.

The photodissociation and photoionization of O2 and the subsequent photodissociation of O2+ in the wavelength region of 200 to 240nm are reported using resonance enhanced multiphoton ionization (REMPI) and velocity map imaging detection. A series of two-photon allowed Rydberg states with principle quantum number n = 3-11 converging to the ground electronic state of O2+X2Πg are used as doorway states to reach the region of superexcited states of O2 in the three-photon energy range of 15.8-18.6eV. A detailed analysis of the kinetic energy release and anisotropy parameters of photofragments extracted from velocity map images reveals competition between neutral dissociation and autoionization and leads to the identification of different O+ formation channels. Moreover, the measurement of anisotropy parameters for each channel gives additional information on the symmetry of electronic states involved in the absorption process. Formation followed by the dissociation of vibrationally excited O2+ is the strongest channel over the full wavelength range studied. Ground and vibrationally excited O2+(X2Πg, a4Πu, A2Πu) are formed and dissociated to ionic products via one and two-photon processes. Neutral dissociation to form electronically excited atoms is important at the longer wavelengths studied and becomes noticeably less important at shorter wavelengths. These results agree with and expand on a previous study from our lab of O+ formation at a single (2 + 1) REMPI wavelength, and the results obtained in this study are found to complement our study of the electronically analogous counterpart S2, where most of the S+ ions arise from electronically excited S* atoms. The results of this study will also be of use in the pixel-to-velocity calibration of any velocity map imaging apparatus in the wide ultraviolet wavelength regions. Because O2 is a common reactant or product in many molecular dynamics studies, knowledge of its ionization/dissociation pathways at commonly used wavelengths should also be useful in avoiding signal overlap problems.

Binding of the commonly used antioxidants (quercetin, resveratrol, and dihydrolipoic acid) to major circulating proteins - spectroscopic and in silico docking and molecular dynamic simulation studies.

Poor bioavailability and reduced stability are the main drawbacks to efficiently utilizing many naturally occurring antioxidants, so their binding to circulatory proteins is essential. This work investigated whether major human circulatory proteins, besides albumin, including transferrin, alpha-2-macroglobulin, and fibrinogen, bind widely consumed antioxidants and food supplements, including quercetin, trans-resveratrol, and dihydrolipoic acid, thus filling the gap of detailed pharmacokinetic properties of these food supplements. Detailed examination of the protein structural and functional changes that occur upon ligand binding was analyzed by spectroscopic methods and in silico docking and molecular dynamic simulation studies on the model that consists of the protein/antioxidant pair with the highest affinity constant. It was found that alpha-2-macroglobulin binds trans-resveratrol with the highest affinity (Ka of 4.5 x 104 M-1). In silico results revealed four potential binding sites between trans-resveratrol and alpha-2-macroglobulin, with hydrogen bonds being crucial for binding, while other observed interactions (primarily aromatic interactions) are of secondary importance. The binding of trans-resveratrol to alpha-2-macroglobulin leads to mutual protection of both molecules from oxidative stress and significantly increased hidrosolubility of resveratrol, both of which could serve to increase the bioavailability and bioactivity of resveratrol in circulation.

An integrative framework to combine migratory connectivity and demographic data

Abstract Migratory species experience various conditions and events throughout their annual cycle that influence their spatial and demographic dynamics. To understand these dynamics, it is essential to describe the origin and destination of individuals. Migratory connectivity, which is defined as the geographic linkage between populations across the annual cycle, is increasingly incorporated in population models to relate population trends to environmental variables at different stages of the cycle. However, such information on migratory movements is obtained independently from the study of population dynamics despite the interaction between both processes. Expanding on the growing use of integrated modelling approaches, we developed an integrated framework that allows the sharing of information between migratory connectivity and population data. We first assembled an integrated migratory connectivity model and an integrated population model to join the analysis of GPS, live‐reencounter, dead‐recovery, capture–mark–recapture, and population count data within a unified framework. Based on simulated data, we assessed the ability of the resulting integrated connectivity and population model to produce unbiased and precise connectivity and demographic estimates. We then applied the same assessment to real data using the Eurasian Curlew (Numenius arquata) as a case study. On simulated data, the integrated connectivity and population model estimated connectivity and survival parameters with no bias and similar precision to the connectivity model alone. However, it outperformed the population model in estimating fecundity in the absence of explicit productivity data. When applied to the Eurasian Curlew, the integrated connectivity and population model produced overall similar migratory connectivity and more accurate demographic estimates than the connectivity model alone, consistent with previous studies. Additionally, the model was able to estimate fecundity, whereas the data were too sparse for the population model alone to disentangle juvenile survival and fecundity. The sharing of information between migratory connectivity and population data improved the estimation of demographic parameters by the population model and improved connectivity parameter estimates when data were scarce. This flexible framework can be generalised to include diverse data on migration movements, population structure, individual heterogeneity or environmental variables, allowing further investigation of the interaction between migration patterns and population dynamics.

Investigation of photophysical properties and potential biological applications of substituted tris(polypyridyl)ruthenium(II) complexes

The photophysical properties of tris(polypyridyl)ruthenium(II) complex [Ru(dmbpy)3]2+ [dmbpy = 4,4′-dimethyl-2,2′-bipyridine] were investigated and compared with [Ru(bpy)3]2+ following both experimental and computational approaches. The variations in the electronic properties of the complex in the ground and excited states were determined by density functional theory (DFT) methods, and their effects on the anticancer, antioxidant, and antimicrobial activities were also evaluated by molecular docking and dynamic simulation studies. The potential of these complexes to serve as bioanalytes was investigated by their ability to bind with quinones, the well-known electron mediators in numerous light-driven reactions. Following the above, the anticancer properties were evaluated against breast cancer-related proteins. The results revealed that the complex possesses comparable anticancer and antioxidant potential to that of [Ru(bpy)3]2+. The physical, electronic, and biological properties of this complex depend on the nature of the ligands and the medium of investigation. Herein, the potential applications of [Ru(bpy)3]2+ in clinical diagnostics as antioxidants and therapeutic agents were evaluated.

Make It or Break It? Pregnancy Scares and Romantic Relationship Dissolution.

Young adult romantic relationships have undergone significant changes in recent decades, resulting in such distinct demographic trends as rising rates of relationship dissolution. Union dissolution during young adulthood can influence future relationship stability, financial well-being, and health. Reproductive experiences are an important factor that can shape relationship stability. Much of past research, however, has focused on the impact of childbearing on relationship stability while less attention has been paid to other reproductive experiences that could also shape relationship stability, such as pregnancy scares. A pregnancy scare is when a woman suspects she has an undesired pregnancy but later discovers she is not pregnant. This experience might increase or decrease relationship stability. Drawing on data collected from young women in the Relationship Dynamics and Social Life study, this analysis examines the association between pregnancy scares and union dissolution. Results suggest that pregnancy scares are negatively associated with union dissolution, and this relationship persists over time; however, this association varies by relationship type, with serious dating relationships experiencing the most protective benefits.

Interfacial properties of composites based on h-BN and c-BN as a function of temperature: A molecular dynamics study

Interfacial properties of composites based on h-BN and c-BN as a function of temperature: A molecular dynamics study

FireVoxel: Interactive Software for Multi-Modality Analysis of Dynamic Medical Images.

This article provides an overview of the FireVoxel software for quantitative analysis of medical images and its applications in the field. We describe FireVoxel's user interface, multi-layer design, dynamic parametric models, and several turn-key workflows. Additionally, we discuss its application in recent imaging projects. We outline basic image analysis tools such as segmentation, non-uniformity correction, and coregistration through a pictorial overview, with a focus on deformable coregistration and motion correction. Several example workflows and image-based dynamic modeling are also highlighted. Furthermore, we analyze peer-reviewed studies that utilized FireVoxel for image processing, categorizing published papers based on body structures/organs, image processing methods, and imaging modalities. For comparison, we searched the Ovid MEDLINE database to assess the general use of medical image analysis software. FireVoxel is used by over 3000 users worldwide, with 528 articles, including 413 in English, published in the past 15years. MRI is the most commonly used imaging modality (78.2%), followed by CT (14.5%) and PET (7.3%). The most frequently used methods are dynamic modeling, segmentation, texture analysis, and coregistration. FireVoxel is commonly used in abdominal and genitourinary imaging studies, where it appears to fill a niche due to the lack of alternative software. The search of the Ovid MEDLINE suggests that quantitative medical imaging studies, on the other hand, focus on the brain and cardiovascular system. FireVoxel offers an effective set of quantitative tools, particularly for abdominal and genitourinary imaging, likely due to its ability to manage patient motion and correct for MR artifacts. The software is especially valuable for processing dynamic studies. The steady increase in publications utilizing FireVoxel reflects growing interest in this software and its relevance for image-based research.

Attosecond electron dynamics in solid-state systems

Abstract Attosecond science has revolutionized the study of ultrafast electron dynamics. Originally based on high-order harmonic generation from intense laser fields, it provided groundbreaking insights into physical processes occurring on the few- to sub-femtosecond time scales. From its initial focus on atomic and molecular systems, the field rapidly expanded to solid-state materials, uncovering phenomena with possible significant implications for information technology. This review focuses on some of the key experimental techniques that enable attosecond resolution in solid-state systems. We categorize them into four main groups: core-hole clock spectroscopy, photoemission, XUV-based all-optical techniques, and sub-cycle strong-field approaches. Together, these methods contributed to significant breakthroughs, such as elucidating the timing of photoemission from solids, possibly enabling the manipulation of the electro-optical properties of a crystal with light fields, and advancing our understanding of fundamental light-matter interactions. Their application to novel materials and the development of innovative, cutting-edge light sources and techniques, will define the future of attoscience in solids, setting the basis for profound advancements in both scientific understanding and technological innovation.

Investigating the protective effects of luteolin and gallic acid from Luffa acutangula L. (Roxb.) amara (Roxb.) C. B. Clarke. Fruit pericarp against alcohol-induced liver toxicity: Extraction, bioactivity-guided fractionation, molecular docking, and dynamics studies.

Luffa acutangula var. amara (Roxb.) C.B. Clarke, known as 'Katu Koshataki' in Ayurveda, is a traditional medicinal plant in India. The juice of these fruits is recommended for chronic alcohol-induced liver diseases. This study aimed to validate the hepatoprotective and antioxidant properties of Luffa acutangula var. amara fruit pericarp ethanolic extract (EOLA) against ethanol-induced chronic hepatotoxicity in rats, isolate bioactive phytochemicals and in silico evaluation. Ethanolic extract of L. acutangula var. amara fruit pericarp was evaluated in chronic alcohol-induced hepatitis (20% ethanol orally twice daily for 28 days) at doses of 100 and 200mg/kg p.o. Additionally, in vivo anti-inflammatory and antioxidant potential were assessed. Luteolin and gallic acid were isolated using bioactivity guided fractionation. Furthermore, these phytochemicals were assessed for hepatoprotective potential using molecular docking and molecular dynamics studies against different targets. The EOLA demonstrated efficacy in stabilizing elevated biochemical markers and antioxidant levels associated with ethanol-induced hepatotoxicity in rats, and it preserved the normal architecture of hepatocytes in histological analyses compared to the ethanol control group. The EOLA was subjected to fractionation using hexane: chloroform (8:2 → 2:8), followed by chloroform: methanol (8:2 → 2:8) to yield a total eight fractions. The fractions 1, 2, and 3 showed potent antioxidant potential, yielding luteolin and gallic acid as LAC-1 and LAC-3 from fractions 1 and 8, respectively. Gallic acid and luteolin were investigated using molecular docking and molecular dynamic simulation techniques to assess their interactions with key proteins such as Cytochrome P450 2C9, Superoxide Dismutase, Glutathione Peroxidase, Glutathione S-Transferase, Catalase, Peroxisome Proliferator-Activated Receptor-ϒ, Vanin-1, and Cannabinoid Receptor CB2. The metabolites exhibit strong binding stability, with a root mean square deviation range of less than 2.8Å. It can be concluded that the fruit pericarp of L. acutangula var. amara could be used as a functional food for reducing the liver damage caused by alcohol and other factors.

Extreme events in the Higgs oscillator: A dynamical study and forecasting approach.

Many dynamical systems exhibit unexpected large amplitude excursions in the chronological progression of a state variable. In the present work, we consider the dynamics associated with the one-dimensional Higgs oscillator, which is realized through gnomonic projection of a harmonic oscillator defined on a spherical space of constant curvature onto a Euclidean plane, which is tangent to the spherical space. While studying the dynamics of such a Higgs oscillator subjected to damping and an external forcing, various bifurcation phenomena, such as symmetry breaking, period doubling, and intermittency crises are encountered. As the driven parameter increases, the route to chaos takes place via intermittency crisis, and we also identify the occurrence of extreme events due to the interior crisis. The study of probability distribution also confirms the occurrence of extreme events. Finally, we train the long short-term memory neural network model with the time-series data to forecast extreme events.

Assessing the Snow Water Equivalent Dynamics of the Brahmaputra River Basin

ABSTRACT The Brahmaputra River Basin holds a crucial position in South Asia’s hydrological framework, serving as a vital source of water for a substantial population. Snow Water Equivalent (SWE), a pivotal metric reflecting water availability in regions dominated by snow, assumes a significant role in shaping the hydrological cycle of the basin. Thus, this present work aims to conduct a comprehensive study of the SWE dynamics across the Brahmaputra River Basin from 1980 to 2021. The present study obtains the data of elevation, ERA5-Land and SWE and SWE maximum, snowfall, snow cover area, snow depth, and air temperature, in a Geographic Information System (GIS) environment. Seasonal and annual trends are analyzed using the Theil-Sen slope estimator and the Mann-Kendall significance test. Correlations and linear regressions are conducted to assess the relationships among the variables. The findings unveil intricate SWE distribution patterns across the study area, with high elevations exhibiting prolonged snow cover area and substantial SWE values. Trend analysis shows a consistent decrease in SWE and SWE maximum across all seasons, ranging from -0.006 (post-monsoon) to -0.034 m (pre-monsoon) water equivalent/decade. Similarly, a declining trend (at a rate of -0.014 m water equivalent/decade) is also observed in annual SWE. The declining seasonal and annual SWE is possibly linked to escalating air temperature, diminishing snowfall, snow cover area, and snow depth during the study period. The implications of these findings underscore the significance of incorporating SWE variations into water management and the assessment of ecosystem health in the region.

Steady-state and dynamic experimental study of an enhanced automotive thermal management system based on energy cascade utilization

Steady-state and dynamic experimental study of an enhanced automotive thermal management system based on energy cascade utilization

Identification of Potential Inhibitors from Medicinal Plant-based Phytochemicals for the Influential C4 Target of Diabetic Retinopathy by Molecular Docking Studies.

Diabetic retinopathy is the major cause of vision failure in diabetic patients, and the current treatment involves the practice of glucocorticoids or VEGF antagonists that are "off-label". A few small organic molecules against DR were discovered many years ago. Nutraceuticals are naturally available functional foods that endorse different health benefits, including vitamins, antioxidants, minerals, fatty acids, and amino acids that can defer the development of some diseases. Numerous studies reported that nutraceuticals encourage multiple therapeutic benefits and provide protection against various diseases. In diabetes, nutraceuticals contribute to improving insulin sensitivity, metabolism regulation, and lower hyperglycemia. The major aim of this study is to discover the most active drug from natural or plant sources. In this work, 42 phytochemical constituents from 4 kinds of plants were docked with the C4 target of diabetic retinopathy by an in silico molecular docking study. According to the binding energy, all the phytoconstituents possessed good to high attraction towards the target, and 6 phytochemicals, such as terchebulin, punicalagin, chebulagic acid, casuarinin, punicalin, and pedunculagin, disclosed superior binding energy towards the target than standard ruboxistaurin via the interactions of conventional hydrogen bonding, pi-alkyl interactions, etc. Molecular dynamic simulation studies further established the stability of the phytoconstituents, and ADMET studies proved the safety profile of these phytoconstituents. Hence, the current study suggested that the phytochemicals from various herbs inhibit the C4 target of diabetic retinopathy and can be utilized as lead compounds to develop analogs or repurposed for the treatment of DR.

A process-based dynamic modelling study of the impact of discharge water from shrimp culture on riverine nitrogen cycling: A case study

A process-based dynamic modelling study of the impact of discharge water from shrimp culture on riverine nitrogen cycling: A case study

Cryptolepine-transferrin nanosystem preparation and the anticancer effects on human malignant glioblastoma U87MG cells.

In this study, the synthesis and characterization of the human transferrin (hTf)-cryptolepine complex nanostructure were performed. The interaction of hTf in the forms of native and nanostructures with cryptolepine was evaluated through various spectroscopic methods, molecular docking, and molecular dynamic (MD) simulation studies. Finally, the anticancer mechanisms of the prepared complex nanostructure on the Human malignant glioblastoma U87MG cell line and normal astrocytes were assessed using cell viability, RT-PCR, and ELISA assays. The data showed that hTf and hTf-cryptolepine complex nanostructures exhibited particle sizes of 149.37 ± 28.98 and 161.85 ± 33.44 nm, and average zeta potential values of -11.85 ± 1.98 and -23.87 ± 2.202 mV, respectively. It was also found that the drug release behavior from the hTf-cryptolepine complex nanostructures displayed a pH-sensitive pattern, demonstrating a strong correlation with the Higuchi model and a moderate correlation with the Korsmeyer-Peppas model. Spectroscopy and MD simulation studies revealed that the interaction of hTf and cryptolepine did not induce significant changes in the structure of the protein. Moreover, binding parameters were determined to be greater for hTf-cryptolepine complex nanostructures compared to the hTf-cryptolepine complex. Cellular assays showed that the calculated IC50 concentrations of cryptolepine, hTf-cryptolepine complex, and hTf-cryptolepine complex nanostructures in Human malignant glioblastoma U87MG cells were 16.1, 14.31, and 4.60 μM, respectively. Furthermore, it was demonstrated that Human malignant glioblastoma U87MG cells treated with hTf-cryptolepine complex nanostructures had a more significant increase in caspase-3 expression and activity compared to free cryptolepine or the hTf-cryptolepine complex. In conclusion, this paper may hold great promise for the introduction of bionanotherapeutics, which require further evaluation in future studies.

Investigations on Lithium decorated light weight BeN4 for reversible and enhanced hydrogen storage; an Ab-Initio Molecular Dynamic (AIMD) study

Investigations on Lithium decorated light weight BeN4 for reversible and enhanced hydrogen storage; an Ab-Initio Molecular Dynamic (AIMD) study