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Abstract: The total surface area of two diesel engine produced soots, a high volatile content NIST standard (termed NIST) and a low volatile content soot (termed NEU), were determined with CO2 adsorption and small angle X-ray scattering (SAXS), as a function of the extent of oxidation. During initial volatilization of condensables of the NIST and NEU soots in a thermogravimetric analyzer, in helium at 1073K, their CO2 surface areas increased sharply from 49m2/g to 273m2/g and from 96m2/g to 367m2/g, respectively. During oxidation, the CO2 surface area increased by an additional 100–150m2/g, until 50% conversion was reached. Thereafter, the CO2 surface area was relatively constant with conversion for the NIST soot, but decreased to 150m2/g for the NEU soot. Three porosity regimes were assumed for the calculation of SAXS areas; they were based on (a) constant density (shrinking core), (b) constant diameter, and (c) an observed (with a TEM) diameter variation. The best agreement between the CO2 and SAXS surfaces area occurred for the constant density assumption, in contrast to the actual measured diameter variation. By applying fractal surface analysis to the SAXS data, this discrepancy is ascribed to the opening up of internal volume to reaction volatilization of condensables and oxidation. [Copyright &y& Elsevier]

Although different fabrication methods and biomaterials are used in scaffold development, hydrogels and electrospun materials that provide the closest environment to the extracellular matrix have recently attracted considerable interest in tissue engineering applications. However, some of the limitations encountered in the application of these methods alone in scaffold fabrication have increased the tendency to use these methods together. In this study, a bilayer scaffold was developed using 3D-printed gelatin methacryloyl (GelMA) hydrogel containing ciprofloxacin (CIP) and electrospun polycaprolactone (PCL)-collagen (COL) patches. The bilayer scaffolds were characterized in terms of chemical, morphological, mechanical, swelling, and degradation properties; drug release, antibacterial properties, and cytocompatibility of the scaffolds were also studied. In conclusion, bilayer GelMA-CIP/PCL-COL scaffolds, which exhibit sufficient porosity, mechanical strength, and antibacterial properties and also support cell growth, are promising potential substitutes in tissue engineering applications., (Creative Commons Attribution license.)

Introduction: Physiological, hormonal, or biochemical changes may be related to the increased morbidity of COVID-19 during pregnancy. Our knowledge remains limited about which pregnant women will worsen and develop complications. The aim was to evaluate the maternal, fetal, and neonatal outcomes in hospitalized pregnant women who delivered while infected with acute COVID-19 and to investigate the possible predictors of poor prognosis in a tertiary pandemic center., Methods: A retrospective cohort study was conducted on pregnant women who required termination or delivery during a COVID-19 infection in a tertiary hospital. Serum markers were analyzed to determine any possible association and the predictive value of these markers to show poor maternal, fetal, and/or neonatal outcomes., Results: Out of 45 patients, 12 had maternal complications (Group 1) and 33 had no maternal complications (Group 2). The mean lymphocyte at hospital admission was measured as 1,175.83 ± 362.0 and 1,735.30 ± 746.1 in Groups 1 and 2, respectively (p=0.02). The lymphocyte count measured at hospital admission showed significance in predicting poor maternal outcome, with an area under the curve (AUC) of 0.737 (95% CI:0.578 to 0.897) and a cut-off value of 1,110 mcL with 82% sensitivity and 67% specificity. Nineteen of the 45 women had fetal complications. Receiver operating characteristic analysis showed maternal lactate dehydrogenase as a significant predictor for poor fetal outcome with a cut-off value of 213 U/L (AUC:0.719; 95% CI:0.566 to 0.872) with 85% sensitivity and 60% specificity., Conclusion: The lymphocyte count can be used as a predictor of poor maternal outcome and lactate dehydrogenase demonstrates poor fetal outcome during hospitalization., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Alanya Tosun et al.)

In this work, the azo dye, (E)-1-[5-(3,4-dimethylphenyldiazenyl)-2-hydroxyphenyl]ethanone, has been synthesized and characterized by IR, and X-ray single-crystal determination. In the theoretical calculations, the stable structure geometry of the isolated molecule in gas phase was investigated under the framework of the density functional theory (B3LYP) with 6-31G (d, p). To designate lowest energy molecular conformation of the title molecule, the selected torsion angle was varied every 10° and the molecular energy profile was calculated from -180° to +180°. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis, and thermodynamic properties were described from the computational process. In addition to these calculations, we were investigated solvent effects on the nonlinear optical properties (NLO) of the title compound., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Theere are two independent mol-ecules in the asymmetric unit of the title compound, C(14)H(11)FN(2)O(2), each with a trans configuration with respect to the azo double bond. The dihedral angle between the aromatic rings is 17.21 (2)° in one mol-ecule and 19.06 (2)° in the other. Each of the independent mol-ecules has an intra-molecular O-H⋯O hydrogen bond. In the crystal, mol-ecules are stacked along [100].

The mol-ecular geometry of the title compound, C(17)H(18)N(2)O(2), displays an E configuration with respect to the azo group. The dihedral angle between the aromatic rings is 10.39 (4)°. In the mol-ecule, an intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif.

The title compound, C(15)H(14)N(2)O(2), an azo dye, displays a trans configuration with respect to the N=N bridge. The dihedral angle between the aromatic rings is 0.18 (14)°. There is a strong intra-molecular O-H⋯O hydrogen bond. Geometrical parameters, determined using X-ray diffraction techniques, are compared with those calculated by density functional theory (DFT), using hybrid exchange-correlation functional, B3LYP and semi-empirical (PM3) methods.

The mol-ecule of the title compound, C(15)H(15)NO(2), crystallizes in a zwitterionic form, and displays an E configuration about the C=N bond. The dihedral angle between the two aromatic rings is 5.59 (6)°. An intra-molecular N-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal structure, pairs of mol-ecules are linked into centrosymmetric R(2) (2)(10) dimers by pairs of O-H⋯O hydrogen bonds. Aromatic π-π inter-actions are observed between the benzene rings of adjacent dimers [centroid-centroid distance = 3.4808 (7) Å].

The mol-ecule of the title compound, C(16)H(17)NO(2), adopts the phenol-imine tautomeric form with a strong intra-molecular O-H⋯N hydrogen bond and an E conformation with respect to the azomethine C=N bond. The dihedral angle between the aromatic rings is 21.23 (9)°. The ethyl group is disordered over two orientations with occupancies of 0.598 (6) and 0.402 (6). In the crystal, the mol-ecules are linked into chains along the b axis by C-H⋯π inter-actions.

The title compound, C(16)H(17)NO(2), crystallizes with three crystallographically independent zwitterionic mol-ecules in the asymmetric unit which differ significantly in the orientations of the propyl side chains. The dihedral angles between the two benzene rings in the three mol-ecules are 6.17 (7), 6.75 (7) and 23.67 (7)°, respectively. In each independent mol-ecule, an intra-molecular N-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, each independent mol-ecule exists as part of an O-H⋯O hydrogen-bonded centrosymmetric R(2) (2)(10) dimer.

In the mol-ecule of the title compound, C(23)H(17)N(3)O(2), the methoxy-phenyl ring is oriented at dihedral angles of 13.34 (12) and 88.83 (12)° with respect to the methyl-phenyl and phthalonitrile rings, respectively; the dihedral angle between methyl-phenyl and phthalonitrile rings is 89.67 (10)°. In the crystal structure, weak inter-molecular C-H⋯N inter-actions link mol-ecules into chains. A weak C-H⋯π inter-action is also found..

The title compound, C(13)H(10)ClNO(2), exists in the phenol-imine form in the crystal, and the aromatic rings are oriented at a dihedral angle of 2.82 (9)°. An intra-molecular O-H⋯N hydrogen bond results in the formation of a planar six-membered ring. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into chains.

The role of endothelin peptides was evaluated on survival and organ injury in a model of polymicrobial sepsis, induced by caecal ligation and puncture with particular emphasis on the timing of the administration of its blocker bosentan in Swiss albino mice (20-40 g). The cardiovascular response pattern in this experimental model was characterized by an early, "hyperdynamic" phase starting at 5 h, followed by a late but "hypodynamic" phase that commence after 20 h, provided that the animals are "resuscitated" by injecting 1 ml of saline i.p. at the end of the surgery. However, if saline resuscitation is omitted, then only hypodynamic pattern is observed starting at 5 h without any hyperdynamic phase. Thus, mice were first allocated into saline-resuscitated or unresuscitated groups and endothelin receptor antagonist bosentan (30 mg kg(-1), i.p., either 5 or 20 h after caecal ligation and puncture) was then administered. The control animals received the solvent of bosentan (i.e., saline: %0.9 NaCl, w/v). The survival rates in each group (n=14) were recorded over the following 144 h. In unresuscitated mice, the overall survival at 144 h was 14.3% in controls while bosentan treatment at 5 h (78.6%, P=0.0018) or 20 h (64.3%, P=0.0183) have both significantly improved the survival. However, in saline-resuscitated mice, bosentan administered at 20 h has significantly improved the survival (71.4%, P=0.0213) while its administration at 5 h has yielded exactly the same percent of survival (i.e., 21.4%) as observed in control animals. The beneficial effects of bosentan in preventing the tissue injury due to caecal ligation and puncture were also observed histopathologically in liver, spleen and kidney. Therefore, we concluded that the blockade of endothelin receptors by using bosentan during the later (hypodynamic) stages of septic shock is a promising therapeutic manoeuvre.