Experimental Research Articles

Emerging Phytochemicals to Treat Leishmaniasis: A Review of Experimental Studies from 2011 to 2021

: Leishmaniasis is a protozoan disease caused by a parasite from the genus Leishmania. It is known as a neglected tropical disease by WHO and is the second-leading cause of death by parasites after malaria. Chemotherapy is the only effective way to control the disease, but treatment options for leishmaniasis are limited. The majority of the drugs are costly, have serious side effects and necessitate hospitalisation. The lack of an effective vaccine, in addition to the emergence of resistance to currently available drugs, has all been raised as major concerns, especially in endemic areas of developing countries. Phytochemicals might contribute to the development of novel and effective drugs for the treatment of leishmaniasis by providing selectively targeted intervention in parasites. Many phytochemicals (quinones, alkaloids, terpenes, saponins, phenolics) and their derivatives are quite active against diverse groups of pathogens, such as viruses, bacteria, fungi and parasites. To date, many phytochemicals have shown potent anti-leishmanial activity with highly selective mode of action. However, due to a lack of interaction between academician and pharma industries none of them has undergone the clinical assessment. The present review will analyse the most promising phytochemicals and their synthetic compounds, which have shown antileishmal activity in in-vitro and subsequently in animal studies from 2011-2021. These phytochemicals are apigenin, hydroxyflavanone, Epigallocatechin-O-3 gallate, caffeic acid, α-bisabolol, β-caryophyllene, ursolic acid, quinones, which have shown notable anti-leishmanial activities in several independent studies.

PAGE: Prototype-Based Model-Level Explanations for Graph Neural Networks.

Aside from graph neural networks (GNNs) attracting significant attention as a powerful framework revolutionizing graph representation learning, there has been an increasing demand for explaining GNN models. Although various explanation methods for GNNs have been developed, most studies have focused on instance-level explanations, which produce explanations tailored to a given graph instance. In our study, we propose Prototype-bAsed GNN-Explainer ([Formula: see text]), a novel model-level GNN explanation method that explains what the underlying GNN model has learned for graph classification by discovering human-interpretable prototype graphs. Our method produces explanations for a given class, thus being capable of offering more concise and comprehensive explanations than those of instance-level explanations. First, [Formula: see text] selects embeddings of class-discriminative input graphs on the graph-level embedding space after clustering them. Then, [Formula: see text] discovers a common subgraph pattern by iteratively searching for high matching node tuples using node-level embeddings via a prototype scoring function, thereby yielding a prototype graph as our explanation. Using six graph classification datasets, we demonstrate that [Formula: see text] qualitatively and quantitatively outperforms the state-of-the-art model-level explanation method. We also carry out systematic experimental studies by demonstrating the relationship between [Formula: see text] and instance-level explanation methods, the robustness of [Formula: see text] to input data scarce environments, and the computational efficiency of the proposed prototype scoring function in [Formula: see text].

Experimental study of oil-water two-phase flow patterns in a vertical large diameter pipe

The flow structure and the phase inversion have great influence on the flow measurement in vertical upward oil-water two-phase flow. This paper attempts to investigate the flow patterns in oil-water flows through a vertical upward large pipe with the designed mini-conductance array probes measurement system and the vertical multi-electrode array (VMEA) measurement system. According to the output waveform of the mini-conductance array probes, the oil-in-water flow, transition flow and water-in-oil flow can be identified effectively. The fluctuating signals of the VMEA is processed by the recurrence plot and the time-frequency representation, the results show that the VMEA conductance signal with average measurement characteristics can realize an effective identification of the above three flow patterns, which has a good agreement with the results of the mini-conductance array probes. Finally, via comparing with previous published flow pattern transition boundary models in different pipe diameters, it is founded that the boundary line of the transition to oil-in-water based on the kinematic wave-based model and the observation-based model in the same diameter pipe are consistent with our experimental data. And the pipe diameter affects the flow pattern transition, compared with the boundary in small diameter pipe, the phase inversion requires a larger oil velocity, and the transition zone becomes narrower in large diameter pipe.

Experimental Study of the Unsteady Heat Transfer of the Wall with Phase Change Interlayer

Experimental Study of the Unsteady Heat Transfer of the Wall with Phase Change Interlayer

Challenges and Perspectives in Experimental Study of Floating Offshore Wind Turbine Control: Insights from Recent Research

Challenges and Perspectives in Experimental Study of Floating Offshore Wind Turbine Control: Insights from Recent Research

A Rationalized Approach to Design and Discover Novel Non-steroidal Derivatives through Computational Aid for the Treatment of Prostate Cancer.

Prostate cancer is one of the most prevalent cancers in men, leading to the second most common cause of death in men. Despite the availability of multiple treatments, the prevalence of prostate cancer remains high. Steroidal antagonists are associated with poor bioavailability and side effects, while non-steroidal antagonists show serious side effects, such as gynecomastia. Therefore, there is a need for a potential candidate for the treatment of prostate cancer with better bioavailability, good therapeutic effects, and minimal side effects. This current research work focused on identifying a novel non-steroidal androgen receptor antagonist through computational tools, such as docking and in silico ADMET analysis. Molecules were designed based on a literature survey, followed by molecular docking of all designed compounds and ADMET analysis of the hit compounds. A library of 600 non-steroidal derivatives (cis and trans) was designed, and molecular docking was performed in the active site of the androgen receptor (PDBID: 1Z95) using Auto- Dock Vina 1.5.6. Docking studies resulted in 15 potent hits, which were then subjected to ADME analysis using SwissADME. ADME analysis predicted three compounds (SK-79, SK-109, and SK-169) with the best ADME profile and better bioavailability. Toxicity studies using Protox-II were performed on the three best compounds (SK-79, SK-109, and SK-169), which predicted ideal toxicity for these lead compounds. This research work will provide ample opportunities to explore medicinal and computational research areas. It will facilitate the development of novel androgen receptor antagonists in future experimental studies.

Triaxial compressive behaviour of ultra-high performance geopolymer concrete (UHPGC) and its applications in contact explosion and projectile impact analysis

Ultra-high performance geopolymer concrete (UHPGC) is increasingly recognised as a promising construction material in protective engineering owing to its exceptional material strength and eco-friendly characteristics. However, there is currently limited research data on the behaviour of UHPGC under complex stress states, and the applicability of some common concrete dynamic constitutive models to UHPGC requires calibration and evaluation. This paper presents an experimental study on the triaxial compression (TXC) behaviour of UHPGC under varying confining pressures with a range of 0-40MPa. The stress-strain curves under various confinement levels and failure patterns of UHPGC are discussed. The results indicate that the peak axial stress and toughness of UHPGC increase with higher confining pressure levels, but it still exhibits noticeable softening behaviour. Under uniaxial compression, UHPGC typically fails with inclined shear and axial tensile cracks, while under TXC, particularly at confining pressures above 20MPa, the failure mode transitions to shear failure with prominent oblique shear cracks. Additionally, existing failure criteria are calibrated to match the strength envelop of UHPGC, with the Power-law failure criterion providing the closest fitting results. Subsequently, utilising both current and pre-existing TXC data, three commonly used concrete constitutive models, including HJC, K&C and CSC, are calibrated with respect to the dominant strength parameters for UHPGC in the finite element (FE) hydrocode ANSYS/LS-DYNA. Further, numerical simulations are conducted to evaluate the effectiveness of such three calibrated concrete models in replicating the response of UHPGC panels exposed to the contact explosion or projectile impact. The simulation results demonstrate that the K&C and CSC models effectively replicate the localised damage of UHPGC panels under contact explosions, while the HJC model more accurately simulates the depth of penetration (DOP) for thick UHPGC panels under projectile impact.

Experimental study of a medical data analysis model based on comparative performance of classification algorithms

Experimental study of a medical data analysis model based on comparative performance of classification algorithms

Resource Letter: Synthesis of the elements in stars

This Resource Letter provides a guide to the literature on the field of nuclear astrophysics, and particularly the origin of the elements. Nuclear astrophysics is a multidisciplinary field that aims at understanding where everything we see around us comes from and how it came to be. Astronomical observations, astrophysics modeling, and nuclear physics experiment and theory come together to answer important questions like: Where and how are the elements created? How do stars evolve? What drives the different types of stellar explosions? What is left behind after the cataclysmic death of a star? This Resource Letter presents our current understanding of the origin of the various chemical elements, together with modern research and new developments in the field, with a particular focus on the measurement of nuclear properties for astrophysical applications.

Cracking the chaperone code through the computational microscope.

The heat shock protein 90 kDa (Hsp90) chaperone machinery plays a crucial role in maintaining cellular homeostasis. Beyond its traditional role in protein folding, Hsp90 is integral to key pathways influencing cellular function in health and disease. Hsp90 operates through the modular assembly of large multiprotein complexes, with their composition, stability, and localization adapting to the cell's needs. Its functional dynamics are finely tuned by ligand binding and post-translational modifications (PTMs). Here, we discuss how to disentangle the intricacies of the complex code that governs the crosstalk between dynamics, binding, PTMs, and the functions of the Hsp90 machinery using computer-based approaches. Specifically, we outline the contributions of computational and theoretical methods to the understanding of Hsp90 functions, ranging from providing atomic-level insights into its dynamics to clarifying the mechanisms of interactions with protein clients, cochaperones, and ligands. The knowledge generated in this framework can be actionable for the design and development of chemical tools and drugs targeting Hsp90 in specific disease-associated cellular contexts. Finally, we provide our perspective on how computation can be integrated into the study of the fine-tuning of functions in the highly complex Hsp90 landscape, complementing experimental methods for a comprehensive understanding of this important chaperone system.

Влияние послеоперационного гипотиреоза на гормональную регуляцию сперматогенеза и функциональное состояние семенников у экспериментальных животных

Abstract: the aim of the study was to determine the effect of postoperative hypothyroidism on spermatogenesis in experimental dogs. Materials and Methods: experimental studies were performed on 20 mongrel male dogs. The study was randomized, 3 groups were identified. The first group was a control group, 4 dogs served as controls. Hemithyroidectomy was performed in the second group, subtotal thyroidectomy was performed in the third group. The operations were performed under general anesthesia. The testes, thyroid gland and blood were the objects of the study. In the postoperative period, biochemical and histological analyses of the removed thyroid gland tissue and testicles of the examined dogs were performed. The determination of hormones in the blood before and after surgery was carried out using a chemiluminescent analyzer Roche Codas E601 (Switzerland). Results: in the course of the study, in the postoperative period, experimental dogs had a decrease in testosterone in serum by 15% on day 5-8, and from 15% to 30.1% on day 20; in dogs after subtotal thyroidectomy, this indicator was 41.1% on day 20 (p < 0.005). Changes in FSH and prolactin in the blood were different in all groups. The FSH index had a significant increase on day 5-8, and a decrease on day 20, and the prolactin index on the contrary: a decrease on day 5-8 and an increase on day 20. The hormonal activity of the thyroid gland was reduced, especially after subtotal thyroidectomy. Morphological studies have shown a marked decrease in the activity of the spermatogenic layer and interstitial edema of the testes on 5-8 days in both groups. On the 30th day, in both groups after surgery, there was a noticeable decrease in both the spermatogenic layer and the interstitial cells of the testes. Conclusion: the results of experimental studies have shown that as a result of hemithyroidectomy and subtotal thyroidectomy, there is a noticeable change in the regulation of spermatogenesis and structural and functional changes in the testes of experimental animals, especially in the iodine-deficient region. Keywords: postoperative hypothyroidism, spermatogenesis, semens, hormones, hemitireoidectomy.

Experimental study on the use of green antimicrobial and plasticized agents during the lining of oil paintings with gelatinous materials

Purpose This paper aims to assess the efficiency of emulsified essential oils in glycerol as eco-friendly antimicrobial and plasticized agents added to the biopolymer of gelatin for lining historical oil paintings on canvases. Design/methodology/approach Cedar oil, cinnamon oil and their mixtures were emulsified in glycerol and incorporated into gelatin adhesive as green biocides and plasticizers. Physical, biological, chemical and mechanical tests were conducted on experimental mock-ups to assess the gelatin-based adhesive formulations for the reinforcement of canvas supports. Scanning electron microscope, colorimetric measurements, antimicrobial activity test, attenuated total reflection-Fourier transform infrared spectroscopy, tensile strength and elongation tests were carried out on the mock-ups before and after the artificial aging. Findings The formulations of gelatin-based adhesive with cinnamon and cinnamon-cedar mixture emulsified in glycerol proved their efficiency on the antimicrobial activity test, chemically delaying the decomposition of gelatin and accordingly providing compatible mechanical properties. Gelatin-based adhesive with emulsified cinnamon oil showed a slight yellowing that was quite improved with the mixture of the cinnamon-cedar-based adhesive formulation. Originality/value This study promotes a green approach to lining historical oil paintings by developing green formulations from bio-based origins that minimize the shrinkage and microbial infection of gelatin for lining paintings.

Mechanics and fracture behavior of rocks with triangular holes: experimental and numerical studies

Mechanics and fracture behavior of rocks with triangular holes: experimental and numerical studies

Experimental and Numerical Simulation Studies Based on the Active Regulation Mechanism of Carbon Stripper

Experimental and Numerical Simulation Studies Based on the Active Regulation Mechanism of Carbon Stripper

Numerical experimental study on the fracture process of shale containing internal prefabricated cracks based on CT scanning with different quartz contents

Numerical experimental study on the fracture process of shale containing internal prefabricated cracks based on CT scanning with different quartz contents

Experimental Study on Dry Milling of Stir-Casted and Heat-Treated Mg-Gd-Y-Er Alloy Using TOPSIS

This study examines the dry milling process of a rare-earth-based magnesium alloy, emphasizing the optimization of the milling parameters and their impact on the surface quality, cutting forces, and the rate of material removal. The objective is to improve our comprehension of the milling behavior of the Mg-Gd-Y-Er alloy. The Taguchi technique is adopted to formulate the experimental design. This study methodically investigates the influence of heat treatment (T4 and T6) on milling performance, and the effects of speed, feed rate, and depth of cut. The output variables considered for this investigation are the surface roughness (Ra, Rz, Sa, and Sz), material removal rate (MRR), and cutting force. To optimize the milling parameters and achieve superior outcomes, the multi-objective optimization technique TOPSIS is used. At a feed rate of 150 mm/min, a spindle speed of 1500 rpm, and a depth of cut of 1 mm, the T4-treated sample exhibits a minimum surface roughness value of 0.0305 µm. The highest resultant force values of 96.4416 N and 176.1070 N for 200 °C and 225 °C T6-treated alloys are obtained by combining process parameters such as a spindle speed of 1500 rpm, a feed rate of 50 mm/min, and a depth of cut of 1.5 mm. Furthermore, the maximum closeness coefficient value is achieved by combining a spindle speed of 1000 to 1500 rpm, a feed rate of 150 mm/min, and a depth of cut of 0.5 mm to 1 mm. The closeness coefficient value is significantly influenced by the most significant process parameters, as indicated by the ANOVA results.

Angular excitation of exceptional points and pseudospetra of photonic lattices

Abstract Optical parity-time ( PT ) symmetry has triggered a plethora of theoretical and experimental studies, and as a result non-Hermitian photonics is one of the frontiers of optics today. From unidirectional invisibility and coherent perfect absorbers to wireless power transfer and ultrasensitive sensors, non-hermiticity led to numerous important applications that rely on gain-loss synthetic structures. In particular, one such structure is that of complex photonic lattices that may exhibit exceptional points (EPs) around which the corresponding sensitivity is increased by orders of magnitude. Here, we investigate a new multiparametric family of non-Hermitian lattices that respects PT -symmetry, and examine their spectral sensitivity in terms of pseudospectra, as well, the angular excitation of the underlying EPs.

The potential protective effect of 3-Hydroxybutyrate against aortic dissection: a mendelian randomization analysis

Background3-Hydroxybutyrate, also called β-hydroxybutyrate, is a significant constituent of ketone bodies. Previous observational and experimental studies have suggested that ketogenic diet, especially 3-hydroxybutyrate, may have a protective effect against cardiovascular disease. However, the relationship between ketone bodies, especially 3-hydroxybutyrate, and aortic dissection remains uncertain.Materials and methodsPublicly accessible data from genome-wide association study (GWAS) was utilized to obtain information on ketone bodies, including 3-hydroxybutyrate, acetoacetate and acetone as exposure respectively, while GWAS data on aortic dissection was used as outcome. Subsequently, two-sample Mendelian randomization (MR) analysis was conducted to examine the potential relationship between ketone bodies and aortic dissection. Then, reverse and multivariate Mendelian randomization analyses were performed. Additionally, sensitivity tests were conducted to assess the robustness of MR study.ResultsThe inverse-variance weighted (IVW) method of Mendelian randomization analysis of gene prediction observed a negative correlation between 3-hydroxybutyrate and risk of aortic dissection (OR 0.147, 95% CI 0.053–0.410). Furthermore, consistent findings were obtained through the implementation of the weighted median, simple mode, Mendelian randomization-Egger (MR-Egger), and weighted mode methods. After adjusting acetoacetate (OR 0.143, 95% CI 0.023-0.900) or acetone (OR 0.100, 95% CI 0.025–0.398), MR analysis of gene prediction still observed a negative correlation between 3-hydroxybutyrate and risk of aortic dissection. No indications of heterogeneity or pleiotropy among the SNPs were detected.ConclusionThe findings from the MR analysis demonstrated that genetically predicted 3-hydroxybutyrate exhibits a protective effect against aortic dissection.

The effect of clinical supervision model on nurses’ self-efficacy and communication skills in the handover process of medical and surgical wards: an experimental study

BackgroundThe handover process is a vital part of patient safety continuity, particularly conducted between nurses at the end of shifts. Nurses often face challenges in handover due to a lack of self-efficacy and inadequate communication skills. The clinical supervision model, by providing emotional, educational, and organizational support, aids in skill acquisition and instills confidence.ObjectiveThis study was conducted to investigate the effect of the clinical supervision model on nurses’ self-efficacy and communication skills in the handover process within medical and surgical wards.MethodThis experimental two-group (pre-and post-test) study was conducted in 2024 at selected hospital affiliated with Isfahan University of Medical Sciences, Isfahan, Iran. Convenience sampling was used, and participants were randomly assigned to either the intervention or control group. Data were collected using the ISBAR communication checklist, communication clarity, the Sherer General Self-Efficacy Scale (GSES), the Visual Analog Scale (VAS) for handover self-efficacy, and the Manchester Clinical Supervision Scale (MCSS). The clinical supervision model and routine supervision were implemented in six sessions for the intervention and control groups, respectively. Data were analyzed using SPSS version 16, employing independent t-tests, covariance analysis, paired t-tests, chi-square tests, and repeated measures ANOVA with a significance level of p < 0.05.ResultsNo significant differences were observed between the intervention and control groups in terms of baseline characteristics. Inter-group analysis indicated that there were no significant differences in the scores of self-efficacy, ISBAR, and communication clarity between the control and intervention groups before the intervention (P > 0.05). According to the intra-group analysis, the ISBAR and communication clarity scores in the intervention group significantly increased over time (p < 0.001), whereas no such increase was observed in the control group. The intervention group showed a significant increase in general self-efficacy (p < 0.001) compared to the control group. Although both groups showed a significant improvement in handover self-efficacy, the mean scores of the intervention group were higher than those of the control group (p < 0.001). The mean score of the Manchester Clinical Supervision Scale in the intervention group was 128.98, indicating the high effectiveness of implementing the clinical supervision model.ConclusionThe findings indicated that the use of the clinical supervision model improves self-efficacy and communication skills in the handover process of nurses in medical and surgical wards. Therefore, it is recommended to use this model in handover training to enhance the quality of care and improve patient safety.

Augmentation of communicative skills among rural high school students in India

IntroductionThis study aims to focus on government school students, who struggle hard to express themselves in English.MethodsA two-group simple randomized design was used for this study, and an experimental study was carried out among 60 rural high school students. ‘Captivating activities’ (listening, speaking, reading, and writing) have been used to find the effect on learners’ communication skills. Furthermore, a pre-test and a post-test were conducted between groups, and their scores were analyzed. A paired sample t-test was carried out to identify the difference between controlled and experimental groups.ResultsThe results showed that there was a significant average difference observed between the pre-test and post-test scores (t28 = 8.327, p = 0.000, p &amp;lt; 0.01) of the experimental group.DiscussionAs an outcome of the tested strategy, it was understood that an English-speaking environment can help students improve their language skills to some extent. It was concluded that the captivating activities (listening, speaking, reading, and writing) are effective for augmenting learners’ communication skills.