The permittivity and conductivity relaxation processes of polyethylene oxide (PEO) composite along with potassium hexachloroplatinate (K2PtCl6) electrolytes additive forming PEO/K2PtCl6 complex ...composite have been investigated. The complex composite has been used as a model for dry‐polymer electrolytes (PEs) due to the fact that, the anion is large enough for mimicking the immobilized anion in real dry‐polymer electrolytes. Stand‐free composite films with 0%, 1%, 3%, and 5% concentrations of K2PtCl6 have been studied using broadband dielectric spectroscopy in the temperatures range from 150 K until 345 K. The microstructural dynamics revealed the α‐, β‐, and σ‐relaxations and their salient spectral characteristics at various concentrations of K2PtCl6 in PEO. The experimental ε” master curves were fitted to HN function for one and/or two relaxation peaks with and without the electrical conductivity contribution in order to investigate the relaxation time (τ), dielectric strengths (Δε), modulus formalism (M”) and the electrical conductivitie (σ). The translational and reorientational degrees of freedom of PEO/K2PtCl6 complex composites are responsible for the relaxation behavior which is predicted to be correlated to the relaxation behavior of the polymer electrolyte below and above the glass transition temperature (Tg). The relaxation time (τ) deduced from β‐relaxation follows Arrhenius‐like behavior while that deduced from α‐relaxation process follows Vogel–Tamman–Fulcher (VTF) behavior.
•Fluoroquinolone (PyridoPyrrole Quinoxaline, PPQ) and gold nanoparticles (AuNPs) to create a synergistic anticancer compound.•1H-NMR chemical shifts with increasing AuNPs content confirms the ...intermolecular tethering primarily via fluorine atoms in (PyridoPyrrole Quinoxaline, PPQ).•The most common coordination mode is bidentate, with one oxygen atom from the deprotonated carboxylic group.
The tethering mechanism between Pyrido Pyrrole Quinoxaline (PPQ) anticancer agent and gold nanoparticles (AuNPs) to form the PPQ/AuNPs complex as a promising anticancer reagent was investigated. Physicochemical properties, including viscosity, self-diffusion coefficients, and local molecular dynamics, of both PPQ and the PPQ/AuNPs complex were systematically examined using advanced techniques such as high-resolution 1H Nuclear Magnetic Resonance (1H-NMR), spin-lattice relaxation time (T1), and self-diffusion coefficient (D) analysis. Various PPQ/AuNPs systems were prepared and analyzed, encompassing concentrations of 0, 1.5, 4, 6.5, 8.3, 10.15, and 11.15 mg of PPQ. The results of T1demonstrated that the predominant intermolecular bonding occurs between AuNPs and fluorine atoms, particularly involving the neighboring proton to the fluorine and nitrogen atoms. Remarkably, the curve of self-diffusion coefficients displayed notable peaks at PPQ concentrations of approximately 4 mg and 8.3 mg. The interaction between PPQ molecules and AuNPs revealed a pronounced affinity for the fluorine sites and hydrogen atoms within the hydroxyl group of PPQ molecules when dissolved in aqueous solutions.
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Synthesized PEO:I
2
complex composite films with different I
2
concentrations were deposited onto fused silica substrates using a dip-coating method. Incorporation of PEO films with I
2
increases the ...electrical conductivity of the composite, reaching a maximum of 46 mS/cm for 7 wt% I
2
. The optical and optoelectronic properties of the complex composite films were studied using the transmittance and reflectance spectra in the UV-Vis region. The transmittance of PEO decreases with increasing I
2
content. From this study, the optical bandgap energy decreases from 4.42 to 3.28 eV as I
2
content increases from 0 to 7 wt%. In addition, the refractive index for PEO films are in the range of 1.66 and 2.00.
1
H NMR spectra of pure PEO film shows two major peaks at 3.224 ppm and 1.038 ppm, with different widths assigned to the mobile polymer chains in the amorphous phase, whereas the broad component is assigned to the more rigid molecules in the crystalline phase, respectively. By adding I
2
to the PEO, both peaks (amorphous and crystal) are shifted to lower NMR frequencies indicating that I
2
is acting as a Lewis acid, and PEO is acting as Lewis base. Hence, molecular iodine reacts favorably with PEO molecules through a charge transfer mechanism, and the formation of triiodide (
I
3
-
), the iodite (
IO
2
-
) anion,
I
2
·
·
·
PEO
and
I
2
+
·
·
·
PEO
complexes. PEO:I
2
complex composite films are expected to be suitable for optical, electrical, and optoelectronic applications.
Methanesulfonic acid (MSA):water-alcohol (ethanol and isopropanol) systems were studied at temperatures in the range from 295 K to 360 K using high-resolution 1H NMR and ac-impedance analyzer in ...order to investigate the formation of ionic charge carriers as well as their transport in these ionic mixtures and the dissociation constants. The obtained dissociation constants of MSA:water-alcohol at water-rich and alcohol-rich sides are higher than the same system without MSA due to higher protonic charge carrier concentrations facilitating the structure diffusion of protons. The dissociation constant at the water-rich side (0.63) is comparable to that at the ethanol-rich side (0.58) and slightly higher due to the higher acidity of water. Remarkably, a plateau in the molecular diffusion coefficients and ionic mobility curves is observed in the region between the water-rich side and the alcohol-rich side and the diffusion self-coefficients in the plateau are higher than everywhere else. The temperature dependence of ionic conductivity in MSA:water-alcohol is dominated by the reduction and rearrangement of the hydrogen-bond strength accompanied by a heating induced networking rather than by an ionic formation process. The degree of hydrophobicity plays a more effective rule in the self-diffusion coefficient and in the ionic conductivity compared to the degree of hydrophobicity in ethanol and isopropanol.
The data are relevant for the understanding and optimization of the properties of PEM fuel cells and for polymeric ion rejection membranes which are based on sulfonic groups (-SO3H). They provide interesting insight into the water dependence of the viscoelastic and kinematic properties, the charge formation mechanism and the dissociation limit, with the presence of a hydrophobic group mimicking the ionization of water into the sulfonated polymeric membrane used in many applications such as in PEM fuel cells.
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•The hydrophobic interaction is not big and is overcompensated by hydrogen bonding.•The dissociation constant at the water-rich side is 0.63.•The dissociation constant at the ethanol-rich side is 0.58.•The density of hydrophobicity plays more effective rule.
To assess the transverse relaxation time T sub(2) and diffusion coefficient D before and following exercise in the tibialis anterior muscle and determine whether T sub(2) and D values were ...correlated. Methods Measurements of T sub(2) and D were performed at 3 T within axial slices through the calf muscles of six healthy volunteers at 95 s intervals before and for 10-12 min after a dorsiflexion exercise to exhaustion. Results The mean standard deviation (SD) of T sub(2) and D before exercise were 32 1.55 ms and 1.52 0.15 mum super(2)/ms, and after exercise were 43 2.5 ms and 1.72 0.13 mum super(2)/ms, respectively. The mean SD inter- individual recovery times of the % change in T sub(2) and D after exercise were 7.9 4.2 and 10.9 7.0 min, respectively. The T sub(2) and D values showed a significant correlation throughout the experiments (r super(2) = 0.45). Conclusions The increase in T sub(2) of skeletal muscle after exercise is correlated with the increase of the diffusion coefficient D and the recovery times appear similar, indicating that any model used to explain T sub(2) increases with exercise must also account for increased diffusion coefficients.
To assess the transverse relaxation time T(2) and diffusion coefficient D before and following exercise in the tibialis anterior muscle and determine whether T(2) and D values were correlated.
...Measurements of T(2) and D were performed at 3 T within axial slices through the calf muscles of six healthy volunteers at 95 s intervals before and for 10-12 min after a dorsiflexion exercise to exhaustion.
The mean +/- standard deviation (SD) of T(2) and D before exercise were 32 +/- 1.55 ms and 1.52 +/- 0.15 mum(2)/ms, and after exercise were 43 +/- 2.5 ms and 1.72 +/- 0.13 mum(2)/ms, respectively. The mean +/- SD inter-individual recovery times of the % change in T(2) and D after exercise were 7.9 +/- 4.2 and 10.9 +/- 7.0 min, respectively. The T(2) and D values showed a significant correlation throughout the experiments (r (2) = 0.45).
The increase in T(2) of skeletal muscle after exercise is correlated with the increase of the diffusion coefficient D and the recovery times appear similar, indicating that any model used to explain T(2) increases with exercise must also account for increased diffusion coefficients.
Because important features may be embedded in fat, and because fat may take part in some disease processes, being able to separate fat and water signals may be of great importance in a number of ...clinical applications. A standard method for fat-water separation is referred to as the Dixon method. It was presented by Dixon in 1984, and originally required the acquisition of two images. Initially this original approach was not fully successful because it assumed the magnetic field to be homogeneous. Approaches such as the 3-point Dixon method have been proposed to overcome the field inhomogeneity problem, at the price of increased overall acquisition time, because at least 3 images are required for the separation. While recent advances in rapid imaging have reduced scan time, the need for acquiring at least 3 images per separated time frame may lead to unacceptably low temporal resolution in the water and fat images in dynamic applications such as cardiac imaging. The objective of the present work is to separate fat and water signals in dynamic objects with essentially no loss in temporal resolution compared to usual, non-separated acquisitions. The approach involves modulating the echo time from time frame to time frame. While a method like UNFOLD shifts the sampling function from frame to frame to provide separation of aliased and non-aliased signals, the present approach instead shifts the echo time from frame to frame to provide separation of fat and water signals. Aliased materials sometimes are assumed not to be very dynamic in UNFOLD, and similarly, fat signal is assumed here not to be very dynamic. Even for a dynamic fat signal, removing at least the low temporal frequencies is expected to enable significant fat suppression in the water images. Results were obtained both in vitro and in vivo, in static and moving objects as well as in human volunteers, on 1.5T and 3T magnetic resonance imaging scanners.
Video-assisted thoracoscopic surgery (VATS) is a safe and effective surgical approach for pulmonary resection. VATS can be accomplished with only a single incision, resulting in less postoperative ...pain and paresthesia, better cosmetic results, and greater patient satisfaction. Single-port VATS (spVATS) has become increasingly common for lung resection. We assess the early surgical and oncological outcomes after adopting this new technique at our tertiary cancer center as the first institution to do so in the country.
Medical records for 257 patients in a tertiary cancer center, with a diagnosis of non-small cell lung cancer, pulmonary metastasis, or other chest-confined pathology, were accessed to obtain perioperative outcomes, pathologic results, post-operative follow-up data, and early surgical and oncological outcomes. All patients underwent spVATS for limited or major lung resection. Simple descriptive analysis was utilized.
spVATS was either performed with curative intent (79.8%, N = 205), or as a diagnostic procedure (20.2%, N = 52). Resection types were subcategorized for curative intent group as limited (73.6%, N = 151), lobectomy (16.6%, N = 34), and complex (9.7%, N = 20). Resection with a negative margin (R0) rate was 100% for the primary lung cancer (PLC) patients and 97% for the pulmonary metastasectomy (PM) group. The complication rate was 5%. Three-year disease-free survival was 87% and 68.5% for PLC and PM group, respectively. The 3-year overall-survival was 91.3% for the PLC and 82.8% for PM. Operation duration showed a downtrend over the study period in each curative subcategory with a borderline difference in the limited resection (P value = 0.05).
All the spVATS procedures were successfully performed without perioperative severe complications or mortality, regardless of complexity. R0 resection was excellent. Middle- and long-term efficacies of spVATS for lung cancer require further follow-up. With proper training, appropriate indication and meticulous application, adopting spVATS is safe and feasible technique that does not compromise surgical and oncological outcomes.
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