Raphanus sativus
(radish) tuber extracts stock solutions were prepared by dissolving radish extracts prepared with certain solvents (distilled water, ethanol and methanol) in dimethyl sulfoxide. ...Negative control (dimethyl sulfoxide, DMSO), positive control mutagen (ethyl methanesulfonate) and
R. sativus
extracts (10 and 20 mg/mL doses) were applied to
Allium cepa
root tips at for 24 and 48 h. For examination under the light microscope, the root tips were placed in fixative, then hydrolyzed and treated with acetocarmine. Chromosomal aberration index (CAI%) was increased as compared with the negative control, but decreased as compared with the positive control after the application of three different extracts. It was put forward that mitotix index decreased with increasing extract concentration applications. In this way, it has been determined that these extracts have an inhibitory effect on cell division at high doses. It has been found that CAI% was an increase with increasing extract concentration. It has been revealed that distilled water, ethanol and methanol extracts have more inhibitory effect on cell division and an increasing frequency of chromosomal anomalies, respectively. As a result of this research,
R. sativus
tuber might cause damage to cells genetic material and spindle formation when used incorrectly.
We present results regarding the longitudinal migrations of cool stellar spots that exhibit remarkable oscillations and explore their possible causes. We conducted analyses using high-quality data ...from nine target systems of various spectral types, spanning from F to M, which were observed by the Kepler Satellite. The systems in which the behaviour of the spots was examined are as follows: KIC 4357272, KIC 6025466, KIC 6058875, KIC 6962018, KIC 7798259, KIC 9210828, KIC 11706658, KIC 12599700, and KIC 8669092. Basic stellar parameters were calculated from light curve analysis using the PHOEBE V.0.32 software, and light curves were modelled to obtain sinusoidal variations occurring out-of-eclipses phases, induced by rotational modulation. Subsequently, we calculated the minimum times of the obtained sinusoidal variations using the Fourier transform. The distributions of
${\theta}_{\min}$
corresponding to these minimum times over time were computed using linear fits to determine the longitudinal migrations of the spotted areas. We then compared the longitudinal migration periods with the stellar parameters found in the literature. In addition, we also found a secondary variation in the spot migrations apart from the linear models. Our results revealed that the longitudinal migration periods vary in relation to the
$B-V$
colour index of the stars.
We present the results obtained from KOI 68AB's light variation, which exhibits a sinusoidal light variation due to the stellar spots. Two active regions longitudinally separated by about 180° ...between the latitudes of +70° and +110° were found. A total of 313 flares were determined, and flare parameters were calculated. The One Phase Exponential Association model was derived using these parameters. The energy saturation parameter Plateau value was found to be 1.219 ± 0.088 s, and its time scale parameter half‐life value was found to be 1,190 s. The flare number per hour, known as N1 frequency, was found to be 0.02406 h−1, while the flare‐equivalent duration emitted per hour, known as N2, was found to be 0.000008. Considering new spectral observations, the target seems to be an eclipsing binary system. Because of this, the light curve is analyzed under an assumption that the target is an eclipsing binary. In these analyses, the sum of the fractional radii is found to be 0.1908, and the fractional radii ratio is 1.8973.
Thiolactone chemistry is a powerful tool for the design of complex multifunctional architectures. In this study, this versatile click‐inspired synthetic strategy is conducted to prepare ...multifunctional dendrimer‐like structures. For this purpose, a thiolactone bearing an isocyanate function, prepared in multigram scale, is utilized for multiple step functionalization starting from a 4‐arm star‐shaped poly(ethylene glycol). Amine‐thiol‐acrylate conjugation is carried out in order to form the aforementioned structures. The efficient aminolysis of the thiolactone ring and the reaction of the generated thiol with the double bond of an acrylate derivative are completed in a one‐pot procedure. The choice of the amine and/or acrylate derivatives can allow the introduction of different functional groups for each new generation, potentially leading to multivalent dendrimer‐like structures.
A thiolactone‐based strategy is conducted to prepare multifunctional dendrimers. In this context, a thiolactone bearing an isocyanate function is reacted with a hydroxyl terminal groups of a 4‐arm poly(ethylene glycol) (step 1). Aminolysis of the thiolactone ring and subsequent thiol‐acrylate reaction leads to a double functionalization (step 2). Repetition of steps 1 and 2 leads to the formation of multifunctional dendrimers.
The purpose of this study was to explore the relationships among the components of preservice science teachers' (PSTs) pedagogical content knowledge (PCK) involving the topic 'ozone layer depletion'. ...An open-ended survey was first administered to 216 PSTs in their final year at the Faculty of Education to determine their subject matter knowledge of ozone layer depletion. Then, the PSTs were classified as high-ability, average-ability, and low-ability groups according to their scores on the survey. The interviews were carried out with 25 randomly selected PSTs from each of these ability groups in order to determine their pedagogical knowledge and investigate the inter-relationships and intra-relationships among the components of the PSTs' PCK for teaching the topic 'ozone layer depletion'. The results showed that there was a significant inter-relationship between the subject matter and pedagogical knowledge of the PSTs. There were also significant intra-relationships among the components of the PSTs' pedagogical knowledge, except for the knowledge of assessment. The results of statistical analyses (multivariate analyses of variance) revealed that there was a significant difference in the degree of the PSTs' pedagogical knowledge by the level of PSTs' subject matter knowledge. These significant results were further supported by evidence from qualitative analyses of the interview data. The implications drawn contribute to the improvement of science teacher education.
In this study, the samples are prepared by solid state reaction method at different weight ratios (0–4%). The characterization of materials produced is conducted with the aid of powder X-ray ...diffraction (XRD), temperature-dependent electrical resistivities (
ρ
-
T
) and magnetization (M–H) measurements. Moreover, the change in the scattering/breaking of cooper-pairs in the small homogeneous clusters in the superconducting paths with the addition of multi-walled carbon nanotube is also examined by the energy gap coefficients. All the experimental findings show that the weight ratio of wt 2% is observed to be the optimum addition level. The XRD results indicate that the MgB
2
material prepared by the optimum level crystallizes better in hexagonal symmetry. The critical current density is found to increase from 1.0 × 10
4
to 2.3 × 10
4
A cm
−2
depending on the increment in the magnetization values. On the other hand, the addition mechanism is noted to degrade slightly the general electrical features, critical transition temperatures, lattice cell constants and crystallite size of MgB
2
material. Regardless, although the carbon nanotube addition seems to be negative effect on some general properties, the fundamental characteristic properties (the crystallinity with smoother crystallographic transition, magnetization values, coupling of adjacent layers, degree of broadening and especially formation of effective nucleation centers for the flux pinning ability) improve seriously at the optimum dopant level. Thus, the MgB
2
prepared with the optimum carbon nanotube concentration can exhibit higher performance against the magnetic field and current in larger magnetic field strengths applied.
Geochemical and sedimentological analyses and C-14 dating of four cores from Erdek and Bandırma Bays were performed to evaluate the metal pollution, history and sources, and content in the southern ...Sea of Marmara (SoM) caused by industrial, agricultural and domestic activities during the sediment deposition. The selected elements' pollution (Al, Fe, Mn, As, Co, Cr, Cu, Hg, Ni, Pb, V and Zn) data were evaluated using contamination factor (CF) and pollution load index (PLI). The sedimentary succession in all cores consists mainly of clay (9-96%), silt (1-78%) and sand (0.1-20%) with small amounts of gravel (0.1-7%). The results of CF and PLI reveal that the upper 20 cm core sediments in Erdek Bay were contaminated with Hg (0.07-1.1 mg/kg), Pb (4-72 mg/kg) and Zn (12-255 mg/kg) by both anthropogenic and lithogenic input via the Biga and Gönen streams. Furthermore, the upper 20 cm of MD72 and BK1 core sediments were moderately polluted with As, Cu, Hg, Pb and Zn caused by the discharge of untreated industrial wastewater and domestic sewage from the surrounding area of Bandırma Bay. Moreover, lithogenic Pb-Zn was transported to Erdek Bay by Biga and Gönen streams from the Pb-Zn mineralized zones in the southern SoM drainage area. C-14 dating reveals that As, Hg, Pb and Zn contamination in the study area was started about 400-500 years before the present based on preliminary sedimentation rate estimates and has increased intensely in the last century. Our work is a significant effort to help the environment protection agency or other stakeholders draw a framework to solve this emerging challenge from sewage and wastewater treatment plants.
The aim of this study is to investigate the filling properties of an agricultural waste, olive pomace powder (OP), for polypropylene (PP) matrix material. Different weight fractions of OP (from 10 to ...40 wt %), which has a median particle size of 21.36 μm (D50) μm, were loaded into PP by high-speed thermo kinetic mixer. In this research, the effects of weight fraction of OP within PP on mechanical, viscoelastic, thermal, chemical, crystallographic, and morphological properties of PP composites were investigated by tensile and three point bending test, dynamic mechanic analysis, thermogravimetric analysis and differential scanning calorimetry, Fourier transform infrared analysis, X-ray diffraction analysis, and scanning electron microscopy. When 40 wt% OP filler was loaded into PP, the Young's modulus and flexural modulus of PP increased by about 62.5% and 19%, respectively. The storage modulus and thermal stability of PP were remarkably enhanced with increasing OP weight fraction.
Background/aim: Coronavirus Disease 2019 (COVID-19) is characterized by an increased risk of thrombotic and hemorrhagic events resulting from endothelial dysfunction. In patients with ST-elevation ...myocardial infarction (STEMI), the dual antiplatelet therapy used to reduce mortality may increase the risk of bleeding. The study aimed to compare the efficacy and safety profiles of P2Y12 inhibitors used during the COVID-19 era. Materials and methods: Three hundred and ninety patients who underwent primary percutaneous intervention for STEMI between January 1, 2020, and December 31, 2021, were included in this study, retrospectively. The patients were divided into groups according to their COVID-19 history and all-cause mortality, cardiac mortality, stent thrombosis, and bleeding complications during hospitalization and at one-year follow-up were compared. Results: The mean age of the patients was 64.3 years and the mean follow-up period was 10.2 months; 80% of the patients were male and 44.6% had a history of COVID-19 infection. The in-hospital mortality rate was 11.3%. Cardiac mortality was significantly higher in the clopidogrel group compared to the other groups, regardless of COVID-19 history (21.9% in the clopidogrel group, 1.6% in the prasugrel group, and 6.7% in the ticagrelor group (p<0.001)). There was no significant difference between the groups in terms of bleeding complications and relation to COVID-19. Conclusion: In STEMI patients treated with different P2Y12 inhibitors, there was no significant difference in mortality, bleeding, stroke, and thrombotic complications, regardless of the presence or absence of COVID-19 infection.
Prime-boost regimens for COVID-19 vaccines elicit poor antibody responses against Omicron-based variants and employ frequent boosters to maintain antibody levels. We present a natural ...infection-mimicking technology that combines features of mRNA- and protein nanoparticle-based vaccines through encoding self-assembling enveloped virus-like particles (eVLPs). eVLP assembly is achieved by inserting an ESCRT- and ALIX-binding region (EABR) into the SARS-CoV-2 spike cytoplasmic tail, which recruits ESCRT proteins to induce eVLP budding from cells. Purified spike-EABR eVLPs presented densely arrayed spikes and elicited potent antibody responses in mice. Two immunizations with mRNA-LNP encoding spike-EABR elicited potent CD8+ T cell responses and superior neutralizing antibody responses against original and variant SARS-CoV-2 compared with conventional spike-encoding mRNA-LNP and purified spike-EABR eVLPs, improving neutralizing titers >10-fold against Omicron-based variants for 3 months post-boost. Thus, EABR technology enhances potency and breadth of vaccine-induced responses through antigen presentation on cell surfaces and eVLPs, enabling longer-lasting protection against SARS-CoV-2 and other viruses.
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•EABR technology engineers membrane proteins to induce assembly of enveloped VLPs•SARS-CoV-2 spike-EABR eVLPs were genetically encoded and delivered as mRNA vaccine•Spike-EABR mRNA elicits higher antibody titers than conventional spike mRNA in mice•Spike-EABR mRNA elicits potent antibody responses against Omicron variants
The SARS-CoV-2 spike protein was engineered to recruit ESCRT proteins to its cytoplasmic tail by adding an EABR motif, which induced the assembly of enveloped virus-like particles. A COVID-19 mRNA vaccine encoding spike-EABR elicited superior antibody responses compared with a conventional mRNA vaccine in mice.
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