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Reduced resting and task-related alpha activity in mine workers: Implications for occupational health and neurodegenerative risk
No full text<p>Underground mine workers face many risk factors at work sites that are known to affect the neural system. Observational studies report that these risk factors precede neuromuscular and neurodegenerative disorders, especially in old-age miners. Neurodegenerative disorders have electrophysiological, anatomical, and functional changes long before symptoms are seen in older adults. Therefore, this study investigated whether risks faced by miners at young ages were reflected in electrophysiological signals. Twenty-one underground miners and twentytwo above-ground workers matched with them in terms of age, education, and working duration were included in this study. Participants were recorded with a 20-channel EEG during the resting-state (eyes open and closed; EO-EC) and the perception of the International Affective Picture System Paradigm (IAPS). Time-frequency analyses were performed for alpha frequency. Rs-EEG results showed a statistically significant difference in alpha power between the EO and EC states in the control group. However, there was no statistical difference in alpha power between these two conditions in the miners. Additionally, we noted a more pronounced decrease in alpha responses in the posterior region during EC in the miners. The group's main effects were statistically significant in event-related alpha responses during emotional responses. Accordingly, event-related alpha responses of the miner group were lower than the control group in terms of both power spectrum and phase-locking. Underground mine workers are cognitively and emotionally affected by risks in the work environment. Electrophysiological changes seen in young underground workers may be a harbinger of neurodegenerative disorders in miners' old age. Our research findings may lead to the development of occupational neuroscience, social policies, and worker health, which are necessary to improve working conditions for mineworkers.</p>
Effects of combined alkalinity and ultrasonication on element release and structural alteration in EAF slag
No full text<p>This study investigated electric arc furnace (EAF) slag dissolution in varying NaOH solutions (10 M, 0.1 M, and 0.01 M) and assessed the impact of ultrasonication on enhancing element release. After conducting dissolution tests based on 1/100 g/mL as the solid-to-liquid ratio, ICP-OES analysis was used in determining the dissolved elemental concentrations, while XRD, FTIR, BET, and XPS measurements facilitated understanding of the alterations in the structure and surface. According to the findings, Al, Si, Ca, and Fe elements dissolved in different concentrations, depending on the alkalinity level and technique applied. Higher alkalinity led to more Al and Si species dissolving, reaching up to 12 % dissolution. In contrast, moderate and slight alkalinity reduced the extent of dissolution (< 5 %) for Al and Si or even caused the disappearance of some species. Additionally, the results showed that ultrasonication provided more element releases, with up to 50 % enhancement, compared with stirring. XRD patterns revealed that the EAF slag had an intricate crystal structure including more than 15 phases. Use of 10 M NaOH solution resulted in a considerable breakdown of the EAF slag structure and the formation of new phases, whereas the change in structure was less prominent in 0.1 M and 0.01 M NaOH conditions. In another aspect, BET analysis showed that both alkalinity and ultrasonication increased the particle surface area. In conclusion, this study revealed that EAF slag released different elements with various concentrations and NaOH molarities, and ultrasonication was able to enhance the dissolution process to a certain degree.</p>
Synthesis and photoluminescence properties of Ce<SUP>3+</SUP>/Tb<SUP>3+</SUP> and Eu<SUP>3+</SUP> ions doped GdB<sub>3</sub>O<sub>6</sub>/Ca<sub>10</sub>(PO<sub>4</sub>)<sub>6</sub>(OH)<sub>2</sub> Core/Shell particles as well as its cytotoxicity against colon cancer cells
No full text<p>In this study, Ce3+/Tb3+ co-doped, Eu3+ doped GdB3O6 phosphor particles were synthesized by sol-gel method, coated with hydroxyapatite (HAP) and loaded with doxorubicin. Different chelating agents and surfactants (Cetyltrimethylammonium bromide (CTAB), citric acid, glycine, ethylenediaminetetraacetic acid (EDTA) and tartaric acid) were used in the synthesis in order to see their effect on the structure. While single phase Gadolinium triborate, GdB3O6 was obtained by using CTAB in precursor solution in the synthesis and Gadolinium orthoborate, GdBO3 produced when EDTA was used in precursor solution. Other organic molecules added to precursor solution produced mixtures of both phases. The highest photoluminescence intensity was obtained in the Gd0.95Ce0.025Tb0.025B3O6 and Gd0.825Eu0.175B3O6. In order to increase the drug loading efficiency, The Gd0.825Eu0.175B3O6 core was coated with Calcium hydroxyapatite, HAP. The core had an average size of 458.65 nm which increased to 616.85 nm after coating as seen with dynamic light scattering (DLS). Gd0.825Eu0.175B3O6@HAP particles were loaded with 7.82 % +/- 0.80 wt doxorubicin and the release was studied at 37 degrees C in pH 7.4 phosphate-buffered saline (PBS) and pH 5.5 acetate buffer solutions. The total number of moles of drug released versus luminescence intensity was measured during the release studies and real-time imaging studies were carried out. Finally, cytotoxicity experiments were performed on HCT-116 colon cancer cells.</p>
Investigating the phytochemical profile, biological potentials, morphological, and anatomical characteristics of <i>Cyclotrichium origanifolium</i> (Labill.) Manden. & Scheng. (Lamiaceae) from Turkey
No full text<p>Cyclotrichium origanifolium, a plant widely used in Eastern and Southern Anatolia for culinary purposes, was subject of this study, which aimed to comprehensively evaluate its potential therapeutic applications. This research stands out due to its holistic approach, combining morpho-anatomical studies, chemical, and biological analyses to explore antioxidant, antidiabetic, anticholinesterase, genotoxic, and anti-genotoxic effects of methanolic and aqueous extracts, as well as flowering aerial part essential oil. It is a perennial plant, typically ranging from 10 to 40 cm in height, with a suffrutescent and highly branched growth habit. Essential oils are produced within glandular trichomes. Oil, analyzed via GC-MS/MS, revealed 24 compounds accounting for 96.4% of oil, with isomenthone (52.4%), pulegone (23.4%), and beta-pinene (9.5%) as predominant components. These findings are significant as they provide new insights into chemical composition of oils, particularly highlighting pharmacologically active compounds. Methanol extract exhibited superior antioxidant activity, correlated with high phenol and tannin content. Essential oil showed moderate inhibition of alpha-amylase (49.54%) and mild inhibition of acetylcholinesterase (11.84%) and butyrylcholinesterase (16.93%), suggesting potential in managing oxidative stress and neurodegenerative diseases. Study also conducted biosafety evaluations using Ames/Salmonella and Allium tests, essential for assessing genotoxic and antigenotoxic potential of natural products. Notably, significant antimicrobial effects were identified, particularly against Pseudomonas aeruginosa and Enterococcus faecalis. Comprehensive analysis and discovery of significant bioactivities position this research as a valuable contribution to field, distinguishing it from previous studies on similar species. This study provides a foundational understanding of morpho-anatomical, pharmacological, biological properties of plant, opening avenues for future research.</p>
How Does Online Professional Development Program Enriched with Collaborative Discussion Develop Teachers' Noticing Skills?
No full text<p>It is known that teacher noticing skills improve through different interventions such as video clubs, lesson study, and short-term professional development programs. However, it is not known whether this improvement is permanent and whether teachers can transfer their noticing skills into the classroom. It is extremely important to provide an enduring change in teacher noticing skills. Rather than short-term programs, implementing long-running professional development programs, which last almost 2 years, enables teachers to maintain their noticing skills. At this point, the current study aims to develop in-service middle school mathematics teachers' professional noticing of students' mathematical thinking on pattern generalization during their involvement in a 2-year online professional development program enriched with collaborative discussion. Accordingly, the study was built on the professional noticing of children's mathematical thinking framework, including three noticing skills: attending, interpreting, and deciding how to respond. Participants comprised 31 in-service middle school mathematics teachers with up to 15 years of professional experience working in public schools in seven different provinces of Turkiye. The teachers participated in the online PDP, including scenarios involving student strategies of particular mathematics content. The analysis of the data gathered from the pre-test and post-test let us conclude that the three noticing skills of the in-service middle school teachers exhibited incredible progress through their involvement in collaborative discussion in a long-running online PDP. Based on this result, the characteristics of the online PDP are put forth to develop teachers' noticing skills.</p>
Manipulation of defect state emission in Zn chalcogenide quantum dots and their effects on chlorophyll spectral response
No full text<p>Water soluble Zn based quantum dots (QDs) are of interest due to their biocompatibility and less toxic features. They have been frequently used in studies related to biotechnology, especially in agriculture studies. However, to control the optical properties of Zn based QDs has still been a challenge. In this work, the defect state emission of ZnSe QDs was successfully controlled through two different routes; 1) By creating a sulfur rich outer region around the Se rich core 2) By changing the capping agent. Gradient alloyed ZnSeS QDs with Se rich core and S rich outer region were successfully synthesized with two different capping agents; N-Acetyl-LCysteine (NAC) and 3-Mercaptopropionic Acid (3-MPA). The contribution of emission originated from surface-defects almost disappeared in NAC capped ZnSeS QDs, with causing a significant increase in photoluminescence quantum yield. The interaction between Zn based QDs with chlorophyll molecules was also investigated. The absorption capacity of chlorophylls significantly enhanced upon interaction with 3-MPA capped ZnSeS QDs. Also, the spectral response of chlorophylls could be modulated through interaction with 3-MPA capped ZnSeS QDs, which could be manipulated by using ZnSeS QDs with different chemical composition. Our results indicated that ZnSeS QDs have potential to be used in agriculture, which could act as a modulator of light-harvesting capacity of chlorophylls. The ability to modulate chlorophyll spectral responses through QD interaction opens new possibilities for optimizing light utilization in photosynthetic organisms, thereby contributing to enhanced crop yields and more efficient use of light energy in natural and artificial ecosystems.</p>
Investigation of feed rate impact on microscale surface textures and turning performance of SiAlON ceramic cutting tools
No full text<p>Microscale textures inspired by nature were created on the rake face of SiAlON ceramic inserts using a femtosecond laser system. A detailed investigation was carried out to study the effect of laser parameters such as power, focal length, passing frequency, and media (air/water) on the inserts. The cutting performance of both the non-textured and textured SiAlON inserts was evaluated in terms of tool wear, chip-tool contact length, shear angle, and chip morphology during high-speed turning operations on INC-718. The optimization of laser parameters revealed that grooves were successfully formed in air, but water disrupted the laser focus, resulting in non-linear grooves. A detailed analysis of cutting insert wear patterns at different feed rates indicated the significant impact of texturing on the rake face. The application of surface texturing reduced crater wear, enhanced wear resistance, and minimized tool-chip contact, especially on the inserts with textured grooves located 100 mu m from the cutting edge. Examination of chip-tool contact length and chip flow angles on textured and non-textured inserts showed that surface texturing reduced contact length and facilitated gradual chip curling, resulting in a decrease in chip flow angles. Surface texturing also reduced chip thickness, increased shear angle, decreased burr formation, and changed chip morphology during high-speed machining of Inconel 718.</p>
A column generation heuristic for simultaneous lot-sizing and scheduling problems with secondary resources and setup carryovers
No full text<p>This study introduces an innovative approach to address the Capacitated Lot-Sizing and Scheduling Problem with Sequence-Dependent Setups (CLSD), considering both the sequence-dependent setups and costs. Facing the challenge of large-scale instances, a Column Generation-based Neighbourhood Search (CGNS) algorithm is proposed, efficiently handling real-life CLSD scenarios with extensions like secondary resources and setup carryover and crossovers. The algorithm demonstrates superior performance compared to commercial solvers and fix and relax-based benchmark algorithms, producing high-quality solutions within specified time limits on large data sets. The study's contributions include a distinctive pattern and column structure in the proposed formulation, effectively managing the exponential increase in decision variables. Test instances and a real- life case study validate the algorithm's applicability to production systems under the CLSD and Capacitated Lot-Sizing Problem (CLSP) frameworks, making it a valuable tool for optimising simultaneous lot-sizing and scheduling challenges in practical settings.</p>
Synthesis, <i>in silico</i> and bio-evaluation studies of new isothiocyanate derivatives with respect to COX inhibition and H<sub>2</sub>S release profiles
No full text<p>The development of H2S-donating derivatives of non-steroidal anti-inflammatory drugs (NSAIDs) is considered important to reduce or overcome their gastrointestinal side effects. Sulforaphane, one of the most extensively studied isothiocyanates (ITCs), effectively releases H2S at a slow rate. Thus, we rationally designed, synthesized, and characterized new ITC derivatives (I1-3 and I1a-e) inspired by the natural compound sulforaphane. The anti-inflammatory properties of these compounds were evaluated by their inhibitory activities against cyclooxygenase targets COX-1 and COX-2. Additionally, the cytotoxicity of the compounds was tested using the MTT assay on LPS-induced RAW 264.7 cells, revealing no cytotoxic effects at low doses. Notably, compounds I1 and fluorine-containing ester derivative I1c emerged as the most potent and selective COX-2 inhibitors, with selectivity indexes of 2611.5 and 2582.4, respectively. The H2S-releasing capacities of ITC derivatives were investigated and compared with that of sulforaphane, showing that while compounds I1-3 exhibit slow and similar H2S release to sulforaphane, the release from compounds I1a-e was not as pronounced as that of the standard. Physics-based molecular modeling studies including molecular docking and molecular dynamics (MD) simulations, binding free energy calculations and absorption, distribution, metabolism, and excretion (ADME) analyses were also conducted. MD simulations analysis underscored the crucial amino acids such as Tyr385, Trp387, Phe518, Val523, and Ser530 in the interactions between I1c hit compound and COX-2. The combined in silico and in vitro findings suggest that compounds I1 and I1c are promising NSAID candidates against selective COX-2 inhibition.</p>