Objectives: Apoptosis, an important mechanism that contributes to cell growth reduction, is reported to be induced by Crocus sativus (Saffron) in different cancer types. However, limited effort has ...been made to correlate these effects to the active ingredients of saffron. The present study was designed to elucidate cytotoxic and apoptosis induction by safranal, the major coloring compound in saffron, in a human prostate cancer cell line (PC-3).
Materials and Methods: PC-3 and human fetal lung fibroblast (MRC-5) cells were cultured and exposed to safranal (5, 10, 15, and 20 μg/ml). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to assess cytotoxicity. DNA fragmentation was assessed by gel electrophoresis. Cells were incubated with different concentrations of safranal, and cell morphologic changes and apoptosis were determined by the normal inverted microscope, Annexin V, and propidium iodide, followed by flow cytometric analysis, respectively.
Results: MTT assay revealed a remarkable and concentration-dependent cytotoxic effect of safranal on PC-3 cells in comparison with non-malignant cell line. The morphologic alterations of the cells confirmed the MTT results. The IC 50 values against PC-3 cells were found to be 13.0 0.07 and 6.4 0.09 μg/ml at 48 and 72 h, respectively. Safranal induced an early and late apoptosis in the flow cytometry histogram of treated cells, indicating apoptosis is involved in this toxicity. DNA analysis revealed typical ladders as early as 48 and 72 h after treatment, indicative of apoptosis.
Conclusions: Our preclinical study demonstrated a prostate cancer cell line to be highly sensitive to safranal-mediated growth inhibition and apoptotic cell death. Although the molecular mechanisms of safranal action are not clearly understood, it appears to have potential as a therapeutic agent.
The SARS-CoV-2 pandemic put a pressure on all healthcare professionals and has affected the delivery of health care services globally. There is a need to understand the impact on different health ...care professionals in different countries. The aim of the present study was to explore the psychological impact of the pandemic among dental staff in Norway in relation to background characteristics, work situation and preparedness of the service.
A structured questionnaire sent electronically to dentists, dental hygienists and dental assistants inquired information about the lockdown period in Norway (13 March-17 April 2020). Distributions of background characteristics, perceptions of preparedness and psychological impact were calculated. Exploratory factor analysis was performed, and Structural Equation Models (SEMs) were used to compare psychological impact between dental professionals treating patients versus not during lockdown.
Among the 1237 respondents, 58.8% worked clinically with patients. The majority were concerned of becoming infected (71.9%), of infecting others (85.4%) and/or of their family becoming infected (76.9%). Respondents who treated patients felt significantly more insecure about whether having become infected or not. The minority felt discriminated (6.7%), worried about death (11.7%), felt that life was threatening (9.8%) or felt loss of control of their lives (8.9%). More than 80% agreed that their workplace handled the situation well. Four factors were retrieved from the factor analysis. SEMs showed that gender and work experience had a significant effect on the factors Instability, Infection and Concerns. Respondents with work experience ≥10 years were less likely to express fear about Instability and Infection. Personnel reporting that their workplace had adequate equipment were also less concerned, however having adequate equipment did not reduce the factor Loss of control.
The present study showed a considerable psychological impact of the COVID-19 pandemic on dental personnel in Norway regardless of working clinically with patients or not. However, working with patients increased the insecurity about own infection status and of infecting people close to them. A safe working environment and adequate infection control measures are associated with less fear of infection and feeling of instability.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, r
. In 2010, a new method using muonic ...hydrogen atoms
found a substantial discrepancy compared with previous results
, which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen
. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e-p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e-p experiments and enabled measurements at very small forward-scattering angles. Our result, r
= 0.831 ± 0.007
± 0.012
femtometres, is smaller than the most recent high-precision e-p measurement
and 2.7 standard deviations smaller than the average of all e-p experimental results
. The smaller r
we have now measured supports the value found by two previous muonic hydrogen experiments
. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant
-one of the most accurately evaluated fundamental constants in physics.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Over the past two decades, single-molecule techniques have evolved into robust tools to study many fundamental biological processes. The combination of optical tweezers with fluorescence microscopy ...and microfluidics provides a powerful single-molecule manipulation and visualization technique that has found widespread application in biology. In this combined approach, the spatial (~nm) and temporal (~ms) resolution, as well as the force scale (~pN) accessible to optical tweezers is complemented with the power of fluorescence microscopy. Thereby, it provides information on the local presence, identity, spatial dynamics, and conformational dynamics of single biomolecules. Together, these techniques allow comprehensive studies of, among others, molecular motors, protein-protein and protein-DNA interactions, biomolecular conformational changes, and mechanotransduction pathways. In this chapter, recent applications of fluorescence microscopy in combination with optical trapping are discussed. After an introductory section, we provide a description of instrumentation together with the current capabilities and limitations of the approaches. Next we summarize recent studies that applied this combination of techniques in biological systems and highlight some representative biological assays to mark the exquisite opportunities that optical tweezers combined with fluorescence microscopy provide.
High integration of renewable energy resources, such as wind turbines, to the power grid decreases the power system inertia. To improve the frequency response of a low-inertia system, virtual inertia ...approach can be used. This letter proposes a control method to decrease the frequency transients and restore frequency to its nominal value. A wind turbine usually works based on maximum power point tracking (MPPT) curves to achieve the maximum power. In this letter, the proposed controller uses a non-MPPT method to leave power for frequency regulation during transients. Moreover, it uses a washout filter-based method to remove the steady-state error in the frequency. Simulation results in the PSCAD environment validate the improved performance of the proposed method during load changes by comparing it with the MPPT and non-MPPT methods.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary Objective Bone marrow lesions (BML), previously denoted bone marrow edema, are detected as water signals by magnetic resonance imaging (MRI). Previous histologic studies were unable to ...demonstrate any edematous changes at the tissue level. Therefore, our aim was to investigate the underlying biological mechanisms of the water signal in MRI scans of bone affected by BML. Methods Tetracycline labeling in addition to water sensitive MRI scans of 30 patients planned for total hip replacement surgery was undertaken. Twenty-one femoral heads revealed BML on MRI, while nine were negative and used as controls (CON). Guided by the MRI images cylindrical biopsies were extracted from areas with BML in the femoral heads. Tissue sections from the biopsies were subjected to histomorphometric image analyses of the cancellous bone envelope. Results patients with BML exhibited an average 40- and 18-fold increase of bone formation rate and mineralizing surfaces, respectively. Additionally, samples with BML demonstrated 2-fold reduction of marrow fat and 28 fold increase of woven bone Immunohistochemical analysis showed a 4 fold increase of angiogenesis markers CD31 and von Willebrand Factor in the BML-group compared to controls. Conclusion this study indicates that BML are characterized by increased bone turnover, vascularity and angiogenesis in keeping with it being a reparatory process. Thus, the water signal, which is the hallmark of BML on MRI, is most probably reflecting increased tissue vascularity accompanying increased remodeling activity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Background
Increased psychological pressure on oral healthcare professionals (OHP) due to COVID-19 has been shown, yet little is known about the long-term psychological impacts. We aimed to ...study the psychological impact of COVID-19 and associated factors including perceived risk and preparedness and vaccination status among OHP in the first year after the lockdown period in Norway.
Methods
A structured questionnaire sent electronically to dentists, dental hygienists and dental assistants inquired experiences and perceptions during the second year following the outbreak in Norway. The questionnaire comprised a COVID-19 fear scale and questions about risk perception, preparedness and vaccination status. Exploratory factor analysis (EFA) and Structural Equation Modeling (SEM) were used to assess psychological impact, perception of risk and preparedness according to vaccination status of the respondents.
Results
The majority of the 708 respondents were female (92.8%), had ten or more years of work experience (67.1%), and worked in public dental clinics (95.9%). Fears and concerns related to COVID-19 were common, 72.6% feared getting infected and 85.4% feared infecting others. Of the 642 respondents who agreed that their workplaces handled the situation well, 55.6% were fully vaccinated. Three factors were retrieved from EFA: Insecurity, Instability and Infection. SEM showed that females were more concerned with Infection, and respondents with long clinical experience were less likely to express fear about Instability. Fully vaccinated individuals felt more insecure about becoming infected, and those agreeing that their workplaces handled the current situation well were concerned with Insecurity.
Conclusions
Despite widespread perception of adequate preparedness and high vaccine coverage, a considerable psychological impact and high levels of fear of COVID-19 were observed among the majority of OHP. Fully vaccinated individuals had a larger psychological burden than not fully vaccinated and those with unknown vaccination status. These findings can inform means and interventions to reduce negative impacts of fear in populations with a high psychological burden.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Reduced-graphene oxide/polypyrrole nanofiber (RGO/PPy-Nf) nanocomposite has been prepared as the electrode material of the supercapacitor. This nanocomposite was prepared via a facile two-step ...process, including exfoliation and reduction of graphene oxide by microwave irradiation (MRGO) and in situ polymerization pyrrole onto it. The morphological, structural, and porosity characterizations of this nanocomposite were shown the proper formation of RGO/PPy-Nf composite with a mesoporous structure. The high specific capacitance of 277 F g
−1
was obtained for the RGO/PPy-Nf nanocomposite at a constant current density of 1 A g
−1
in a 1 M H
2
SO
4
solution electrolyte. This nanocomposite revealed the highest energy density of 38.5 Wh kg
−1
with a corresponding power density of 500 W kg
−1
, and the capacitive retention of 95% after 1000 cycles. In evaluating the samples by electrochemical impedance spectroscopy, the values of capacitor response time revealed that the dominant mechanism in pristine PPy and MRGO is faradaic reactions and electrical double-layer capacitance (EDLC), respectively, and both mechanisms play a role in the RGO/PPy-Nf nanocomposite. Also, the relaxation time investigation revealed this nanocomposite exhibit an ideal capacitive behavior at very low frequency.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75 (GeV/c)^{2}. Combined with existing data, these provide an ...improved extraction of the proton magnetic form factor at high Q^{2} and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q^{2} and attributed to hard two-photon exchange (TPE) effects, extending to 8 (GeV/c)^{2} the range of Q^{2} for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q^{2}.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
The Spin Asymmetries of the Nucleon Experiment measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 and 5.9 GeV. A ...large-acceptance open-configuration detector package identified scattered electrons at 40° and covered a wide range in Bjorken x (0.3<x<0.8). Proportional to an average color Lorentz force, the twist-3 matrix element, dover ˜_{2}^{p}, was extracted from the measured asymmetries at Q^{2} values ranging from 2.0 to 6.0 GeV^{2}. The data display the opposite sign compared to most quark models, including the lattice QCD result, and an unexpected scale dependence. Furthermore, when combined with the neutron data in the same Q^{2} range the results suggest a flavor independent average color Lorentz force.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM