3036 research outputs found
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Preparation, Characterization, and In Vitro Antioxidant and Antibacterial Activity
No full textThe aim of this study is to improve the solubility, chemical stability, and in vitro biological activity of caffeic acid phenethyl ester (CAPE) by forming inclusion complexes with β-cyclodextrin (β-CD) and hydroxypropyl-β-cyclodextrin (Hβ-CD) using the solvent evaporation method. The CAPE contents of the produced complexes were determined, and the complexes with the highest CAPE contents were selected for further characterization. Detailed characterization of inclusion complexes was performed by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrospray ionization-mass spectrometry (ESI-MS). pH and thermal stability studies showed that both selected inclusion complexes exhibited better stability compared to free CAPE. Moreover, their antimicrobial activities were evaluated against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) for the first time. According to the broth dilution assay, complexes with the highest CAPE content (10C/β-CD and 10C/Hβ-CD) exhibited considerable growth inhibition effects against both bacteria, 31.25 μg/mL and 62.5 μg/mL, respectively; contrarily, this value for free CAPE was 500 μg/mL. Furthermore, it was determined that the in vitro antioxidant activity of the complexes increased by about two times compared to free CAPE. © 2024 The Authors. Published by American Chemical Society
Added Qualities of New Interventions within the Historic Built Environment
No full textContemporary architecture, within the historic urban settings, is acquired as the contribution of the current time to a particular existing ambience, whereas new interventions are expected to be significant authorship achievements. This paper discusses the new qualities within the historic urban fabric produced by the contemporary interventions, in particular, those of balanced contrast. Such new spatial contributions may be applied on different levels (ambience (urban), object and detail), while each of them is expected to produce added qualities. Built on different theories about space qualities and characteristics, this paper evaluates selected examples by distinguishing three major groups of produced qualities (physical, economic and socio-cultural). This paper also suggests balanced contrast applied to new interventions within the valuable historic ambience as an acceptable approach. Finally, the correlation of all comprising elements of the newly design objects with the surroundings is emphasised to be important in producing new values. © 2023, Strojarski Facultet. All rights reserved
Adaptation of n-out-of-n secret sharing scheme into IoT network
No full textInternet of Things (IoT) has become an established part of our daily lives by interconnecting billions of devices in diverse areas such as healthcare, smart home technologies, agriculture, etc. However, these devices are limited in memory, energy and computational capabilities. This creates a great potential for security issues to arise as being constrained prevents them from applying complex cryptographic algorithms. In this study, we propose a novel method to provide a low-cost and secure communication for constrained IoT devices. The proposed method is based on a n-out-of-n secret sharing scheme and mimicks the idea of visual cryptography in a digital set-up.Generally, when an IoT device communicates with an outer party, it establishes the communication by itself or through a mediary such as a central hub or gateway; which leads to single point of failure. Our proposed method aims for a distributed environment in which devices collaborate with each other and therefore divide the responsibility of sending a message into multiple devices, instead of just one device. Therefore, when a device plans on sending a message, all its neighbors send it on the behalf of this device. © 2023 IEEE
IDENTIFICATION OF PHENOLIC COMPOUNDS AND CHANGES IN THEIR CONTENT DURING PROCESSES OF WHITE WINES
No full textGaziantep (in Turkey) is one of the oldest cities in the World, in which the history of winemaking and viticulture began in ancient ages. It is home to wild white grapes Vitis vinifera Dokulgen and Paf. Three young white wines were produced from these two grapes. Ten phenolics and some chemical characteristics were quantitatively detected in the white wines and musts depending on white wine processes. Phenolic compounds significantly (p < 0.05) increased during the fermentation process. After aging, (+)-catechin and procyanidin B2 contents of white wines were ranged from 1.12 to 1.35 and from 60.69 to 69.02 mg/L respectively. After aging, the quercetin, rutin and myricetin contents of white wines-1, 2 and 3 were ranged from 0.47 to 0.59, from 0.28 to 0.32 and from 0.11 to 13 mg/L respectively. White wines represented with abundant flavanols, tyrosol and chlorogenic acid produced from Dokulgen and Paf mixture with 7:3 ration. It was found that there is a significant difference between hydroxycinnamic acid and hydroxybenzoic acid content of white wines. Dokulgen and Paf white grapes contribute higher amount of phenolic characteristics, better acidity and sugar to white wine while Dokulgen grape contributed more sugar
THE MEDIATING ROLE OF JOB SECURITY IN THE IMPACT OF DIGITAL LEADERSHIP ON JOB SATISFACTION AND LIFE SATISFACTION
No full textDigital leadership emerges as the reflection of technological innovation in business life into administration mentality. As well as possessing leadership skills, digital leaders can be defined as leaders who are talented in terms of information technologies, visionary, can think innovatively, increase the corporation's performance and create the transformation required by the business. The literature emphasizes that digital leadership practices and digital transformation efforts can fail due to fear of being unemployed, the tendency to maintain the usual, and showing resistance to transformation. However, it is realized that these approaches are generally based on foresight and are not supported by real practices. In this regard, the mediating effect of job security satisfaction of employees on the impact of digital leadership upon job satisfaction and life satisfaction is tried to be explained with application findings by utilizing from Resource Based View (RBV). The study was conducted with 403 employees working in an industrial organization. The data obtained were analysed through the Smart-PLS program, and the mediating effect was measured using a structural equation model. The model found that digital leadership had a significant effect (0.199) on job satisfaction, digital leadership had a significant effect (0.182) on life satisfaction, and digital leadership had a significant effect of 0.312 on the perception of job security. Once again, it was found that the perception of job security had a partial mediating effect (0.156) on the effect of digital leadership upon job satisfaction, and the perception of job security had a partial mediating effect (0.150) on the effect of digital leadership upon life satisfaction. The present study indicated that in a well-designed digital transformation, digital leaders could increase employees' job and life satisfaction, and job security had a mediating impact upon this increase. Digital transformation in businesses creates an environment that allows high-performing employees to stand out more than low-performing employees and to display their talents. Thus, it could be stated that digital technologies have a significant effect on the prominence of talented individuals and increase employees' job satisfaction and life satisfaction by utilizing RBV, as well. As a consequence of its structural characteristics, digital leadership paves the way for more effective use of human resources in the enterprise, the realization of the necessary organizational transformation, and the increase in the perception of job security of the employees thanks to the contribution it provides to the qualitative improvement of the organization
Expression of genes related to iron homeostasis in breast cancer
No full textBackground The dysfunctions in the metabolism of iron have an important role in many pathological conditions, ranging from disease with iron deposition to cancer. Studies on malignant diseases of the breast reported irregular expression in genes associated with iron metabolism. The variations are related to findings that have prognostic significance. This study evaluated the relationship of the expression levels of transferrin receptor 1 (TFRC), iron regulatory protein 1 (IRP1), hepcidin (HAMP), ferroportin 1 (FPN1), hemojuvelin (HFE2), matriptase 2 (TMPRSS6), and miR-122 genes in the normal and malignant tissues of breast cancer patients.
Methods & Results The normal and malignant tissues from 75 women with breast malignancies were used in this study. The patients did not receive any treatment previously. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used in figuring the levels of gene expression associated with iron metabolism. When the malignant and normal tissues gene expression levels were analyzed, expression of TFRC increased (1.586-fold); IRP1 (0.594 fold) and miR-122 (0.320 fold) expression decreased; HAMP, FPN1, HFE2, and TMPRSS6 expressions did not change. FPN1 and IRP1 had a positive association, and this association was statistically significant (r = 0.266; p = 0.022). IRP1 and miR-122 had a positive association, and this association had statistical significance (r = 0.231; p = 0.048).
Conclusions Our study portrayed the important association between genes involved in iron hemostasis and breast malignancy. The results could be used to establish new diagnostic techniques in the management of breast malignancies. The alterations in the metabolism of malignant breast cells with normal breast cells could be utilized to achieve advantages in treatment
Comparative GC-MS Analysis of Fresh and Dried Curcuma Essential Oils with Insights into Their Antioxidant and Enzyme Inhibitory Activities
No full textSpecies belonging to the Zingiberaceae family are of high nutritional, industrial, and medicinal values. In this study, we investigated the effect of processing steps (fresh vs. dried milled rhizomes) and extraction methodologies (hydrodistillation vs. hexane extraction) of curcuma essential oil on its chemical content (using GC-MS analysis), its antioxidant behavior (using in vitro assays such as DPPH, ABTS, CUPRAC, FRAP, phosphomolybdenum, and metal chelation), and its enzyme inhibitory activities (on tyrosinase, acetylcholinesterase, butylcholinesterase, α-amylase, and α-glucosidase) supported by multivariate analysis, in silico studies, and molecular dynamics. The GC-MS investigations revealed a high degree of similarity in the chemical profile of fresh hydrodistilled and hexane-extracted essential oils with tumerone and curlone being the major metabolites. The extraction techniques affected the concentrations of other minor constituents such as terpinolene, caryophylla-4(12), 8(13)-dien-5α-ol, and neo-intermedeol, which were almost exclusively detected in the hydrodistilled fresh essential oil; however, zingiberene and β-sesquiphellandrene were predominant in the hexane-extracted fresh essential oil. In the dried curcuma rhizomes, tumerone and curlone contents were significantly reduced, with the former being detected only in the hydrodistilled essential oil while the latter was doubly concentrated in the hexane-derived oil. Constituents such as D-limonene and caryophyllene oxide represented ca. 29% of the dried hydrodistilled essential oil, while ar-turmerone was detected only in the dried hydrodistilled and hexane-extracted essential oils, representing ca. 16% and 26% of the essential oil composition, respectively. These variations in the essential oil chemical content have subsequently affected its antioxidant properties and enzyme inhibitory activities. In silico investigations showed that hydrophobic interactions and hydrogen bonding were the characteristic binding modes of the bioactive metabolites to their respective targets. Molecular dynamics revealed the stability of the ligand-target complex over time. From the current study we conclude that fresh hexane-extracted essential oil showed the best radical scavenging properties, and fresh rhizomes in general display better enzyme inhibitory activity regardless of the extraction technique. © 2023 by the authors
Examination of Nursing Students’ Opinions, Experiences and Attitudes Toward Medical Errors: A Cross-sectional Study
No full textAim: The aim of this study was to reveal nursing students’ opinions, experiences, and attitudes toward medical errors.
Method: This descriptive and cross-sectional study was conducted among 465 third and fourth-year nursing students in Turkey.
Data were collected between March-June 2017 using a demographic information form and the Medical Error Attitude Scale. Data
analysis was performed using descriptive statistics of mean, standard deviation, number, and percentage and the Mann-Whitney
U test.
Results: The majority of students stated that they did not make any medical errors in clinical practice (76.8%) and if they made
any medical error, they said they would report it to the charge nurse (72.7%). Only 5.8% of the students stated that they reported
the medical error they made. While the students’ total Scale of Attitudes toward Medical Errors mean score was 3.78 (SD=0.47),
the subscale mean scores were determined to be 2.79 (SD=0.71) in the medical error perception, 3.94 (SD=0.60) in the approach
to medical errors, and 3.90 (SD=0.59) in the causes of medical errors subscale. There were statistically significant differences
between gender, age group, and class year of students and the Scale of Attitudes toward Medical Errors total and subscale mean
scores (p<0.05; p<0.01).
Conclusion: Nursing students’ attitudes toward the approach to medical errors, causes of medical errors, and general medical
errors were positive. In contrast, their attitude toward the medical error perception was negative. This result indicates that students’
awareness of medical errors and the importance of error reporting is high. Moreover, while the majority of the students stated that
they did not make medical errors in their clinical practice, they stated that the majority of medical errors were caused by doctors
and nurses
Phenolic compounds as histone deacetylase inhibitors: binding propensity and interaction insights from molecular docking and dynamics simulations
No full textHistone deacetylases are well-established target enzymes involved in the pathology of different diseases including cancer and neurodegenerative disorders. The approved HDAC inhibitor drugs are associated with cellular toxicities. Different phenolic compounds have been shown to possess inhibitory activities against HDACs and are, therefore, considered safer alternatives to synthetic compounds. Here, we elucidated the binding mode and calculated the binding propensity of some of the top phenolic compounds against different isoforms representing different classes of Zn2+ ion-containing HDACs using the molecular docking approach. Our data reaffirmed the activity of the studied phenolic compounds against HDACs. Binding interaction analysis suggested that these compounds can block the activity of HDACs with or without binding to the active site zinc metal ion. Furthermore, molecular dynamics (MD) simulations were carried out on the selected crystal and docking complexes of each selected HDAC isoform. Analysis of root-mean-square displacement (RMSD) showed that the phenolic compounds demonstrated a stable binding mode over 50 ns in a way that is comparable to the cocrystal ligands. Together, these findings can aid future efforts in the search for natural inhibitors of HDACs
Analysis of changes in brain morphological structure of taekwondo athletes by diffusion tensor imaging
No full textObjective: Taekwondo, which is the most preferred sport among the martial arts, is known to improve individuals
physically, spiritually and mentally. The aim of this study is to reveal the effect of teakwondo sport on the brain
and brain structures.
Design;: 30 taekwondo athletes and 15 control groups were included in this study. Diffusion tensor MR images of
each participant were taken. The information was obtained by the self-declaration of the athletes, whether they
were sports years, amateur or elite.
Method: Total brain volume and volumes of white matter, gray matter, frontal lobe, precentral gyrus, corticospinal tract, basal nuclei, postcentral gyrus, hippocampus and amigdala and the ratio of these volumes to total
brain volume were evaluated statistically between the groups using MriCloud software and ROIEditor program.
Results: An increase in total brain volume, gray matter, frontal lobe and precentral gyrus volume in athletes was
associated with taekwondo training. When the ratio of brain parts to total brain volume was examined, it was
determined that there was a difference in the ratio of gray matter, white matter volumes in amateur athletes,
right frontal lobe, left corticospinal tract, right postcentral gyrus volumes in elite athletes, and left postcentral
gyrus volumes of both athletes compared to sedentary individuals.
Conclusions: The increase in the volume of gray matter, frontal lobe, postcentral gyrus and corticospinal tract
together with the brain volume shows that taekwondo exercise contributes to physical, spiritual and mental
development