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In traditional stability analyses of three-dimensional slopes, soil has often been treated as a homogeneous material with single-parameter properties, overlooking the variability inherent in the strength parameters and unit weight of natural soil. This oversight can lead to an overestimation of slope stability and reliability. To address this issue, this manuscript introduces a novel approach. Initially, a horn-shaped double logarithmic spiral failure mechanism for three-dimensional slopes is constructed based on the kinematic approach within the framework of limit analysis theory. The critical height of the three-dimensional slope is calculated using the mean values of soil properties. Subsequently, the stochastic response surface method is employed to formulate a limit state equation for three-dimensional slopes, with three different algorithms utilized to analyze failure probability. Two cases are employed to validate the proposed method and to assess the efficiency and accuracy of the algorithms. Further, a back analysis of the probabilistic distribution of strength parameters for three-dimensional slopes is performed using the stochastic response surface limit state equation. The findings reveal that the relative width of the three-dimensional slope, the coefficient of variation (COV) of strength parameters, and unit weight significantly affect slope reliability. An increase in relative width leads to higher failure probability, while larger COV values for strength parameters and unit weight correspond to higher failure probability. Through back analysis, the results considering parameter variability align more closely with strength parameters obtained from in situ experiments. [ABSTRACT FROM AUTHOR]

Two new Schiff‐base bismuth (III) complexes were prepared by an equivalent reaction between Schiff‐base ligand and Bi (NO3)3•5H2O with the assistance of Mannitol. The chemical structures of the two complexes were characterized by spectroscopic studies (FT‐IR, NMR, and MS), elemental analysis, and single‐crystal X‐ray diffraction. The ligand‐to‐metal ion ratio was found to be 1:1 in the complexes. During the formation of the complexes, Schiff bases changed from the amidic forms to the iminol forms, and the resulting tautomers could coordinate with bismuth (III) ions to produce dinuclear BiIII complexes(1a and 2a). Structural analyses showed that each Bi (III) ion held a distorted capped octahedron geometry with a seven‐coordinate mode in two complexes. Screening in vitro biological activities revealed that two bismuth (III) complexes exhibited much higher antimicrobial and cytotoxic activity than their parent ligands. The cytotoxic activity of the complex(1a) was close to that of the known anticancer drug (Doxorubicin) by evaluating against SGC7901 cells, with the IC50 value 0.59 μM. The complex(1a) could effectively induce SGC7901 cell apoptosis and its oral acute toxicity for LD50 value was found to be 576 mg kg−1. The content of bismuth (III) in mitochondria was higher than that in the nucleus. [ABSTRACT FROM AUTHOR]

Schiff base {(E)‐4‐((2‐hydroxy‐3‐methoxybenzylidene)amino)‐1,5‐dimethyl‐2‐phenyl‐1,2‐dihydro‐3H‐pyrazol‐3‐one} was prepared by the condensation reaction between 2‐hydroxy‐3‐methoxybenzaldehyde and 4‐aminoantipyrine. In the process of forming the title complex, Schiff base was first coordinated with CuII ions to form the mononuclear CuII complex (abbreviated as the complex (I)). Next, Schiff base in the complex (I) removed a phenyl group and then changed from the amide to the iminol. The tautomer further formed the complex through the iminol oxygen, and the phenolic oxygen coordinated with metal ions (CuII and BiIII). The structure of the polynuclear CuIIBiIII complex (abbreviated as the complex (II)) was identified as [Bi2Cu6 L6O3] (L = C13H13N3O3) by elemental analysis, FT‐IR spectra, and single‐crystal X‐ray diffraction analysis. The antibacterial effect of Schiff base and its complex (II) were assessed on four bacterial strains involving gram‐positive strains (S. aureus and B. subtilis) and gram‐negative strains (E. coli and P. aeruginosa). The complex (II) exhibited stronger antibacterial activity than Schiff base. Assessment of cytotoxic activity against SNU‐16 cells (Human gastric cancer) has demonstrated that the complex (II) was more active than Schiff base, and their IC50 values were 0.29 and 1.83 μM, respectively. [ABSTRACT FROM AUTHOR]

A new bismuth(III) Schiff‐base complex [Bi2(HL)2(NO3)4(CH3OH)]•2CH3OH was prepared by reaction of the equivalent molar of Schiff‐base ligand [H2L = (E)‐N′‐(2‐hydroxy‐4‐methoxybenzylidene)isonicotinohydrazide] and Bi (NO3)3•5H2O with the assistance of mannitol. The complex was structurally characterized by elemental analysis, spectroscopic methods (FT‐IR, MS, 1HNMR, and 13CNMR) and single crystal X‐ray diffraction. The molecular structure of the complex reveals that the ligand forms a 1:1 complex with bismuth(III) ion. It is composed of two 7‐coordinated bismuth(III) ions, two tetradentate O2N‐donor ligands, four nitrate ions, and three methanol molecules. The complex and its free ligand were evaluated against gram‐positive bacteria (Staphylococcus aureus, Bacillus subtilis) and gram‐negative bacteria (Escherichia coli, Pseudomonas aeruginosa). The complex was more active than the ligand against all bacterial strains. Their cytotoxic activity was also investigated against SNU‐16 cell. The complex is approximately three times more potent than the ligand, with the IC50 values 0.35 and 1.18 μM for the complex and its ligand, respectively. [ABSTRACT FROM AUTHOR]

A new N-alkylation Schiff base [N2,N6-bis(2-hydroxy-3-methoxybenzyl)pyridine-2,6-dicarboxamide] was synthesized from o-vanillin and pyridine-2,6-dicarboxamide by a solid-phase microwave green synthesis without catalyst and solvent. A new bismuth(III) complex was prepared by reaction of the ligand with BiCl3. The ligand and its bismuth(III) complex were characterized by elemental analysis, spectral techniques (1HNMR, MS, FT-IR and UV), chemical analysis, thermogravimetric analysis and molar conductance. The compositions of the ligand and its bismuth(III) complex were (C23H23N3O6) and Bi(C23H21N3O6)Cl. Moreover, the antibacterial activity of the ligand and its bismuth(III) complex against S. pombe was evaluated by bio-microcalorimetry at 32 °C. The quantitative relationship between some thermokinetic parameters (k, tG and I) with the concentration (c) of the ligand and its bismuth(III) complex was investigated. The half inhibition concentrations (IC50) of the ligand and its bismuth(III) complex were obtained as 4.63 × 10–3 mol dm−3 and 2.10 × 10–3 mol dm−3, respectively. The results showed that the antibacterial activity of bismuth(III) complex was stronger than that of the ligand. Further, the action target of bismuth(III) complex on bovine serum albumin (BSA) was studied by the molecular docking simulation method, and we found that bismuth(III) complex bounded at in the hydrophobic cavity of the substructure domain IIB of BSA. [ABSTRACT FROM AUTHOR]

A new bismuth(III) Schiff‐base complex [Bi2(HL)2(NO3)4] was synthesized by using equivalent molar of Schiff‐base ligand [H2L = (E)‐N′‐(2‐hydroxy‐3‐methoxybenzylidene)isonicotinohydrazide] and Bi(NO3)3•5H2O with the assistance of Mannitol. The complex was structurally characterized by elemental analysis, spectroscopic methods, and single crystal X‐ray diffraction. The experimental and theoretical vibrational bands (infrared and Raman spectra) have been discussed. The antimicrobial activity of the complex against Schizosaccharomyces pombe was evaluated by bio‐microcalorimetry at 32°C. Some thermokinetic parameters (k, Pmax, tG, and Qtotal) were obtained from the metabolic power–time curves of S. pombe, and their quantitative relationships with the concentration (c) were discussed. The half inhibition concentrations (IC50) of isoniazid, Schiff base, and the complex were calculated. The complex showed the strongest inhibition effect among three compounds. [ABSTRACT FROM AUTHOR]

Reaction of silver nitrate with 2‐aminobenzothiazole (abbreviated as Habt) in methanol at 45°C gave mononuclear complex of formula [Ag (Habt)2]NO3•CH3OH. The structure of the complex was characterized by infrared (IR) spectra, single crystal X‐ray diffraction, and elemental analysis. X‐ray diffraction analysis indicated that the title complex was crystallized in the triclinic crystal system with space group P–1, in which silver(I) ion was coordinated to two 2‐aminobenzothiazole ligands through the benzothiazol nitrogen atom. Theoretical study of the complex was carried out by density functional theory (DFT) B3LYP method. The antimicrobial effects of the ligand and its silver(I) complex were evaluated by bio‐microcalorimetry on the growth of Schizosaccharomyces pombe (S. pombe). Some quantitative metabolic parameters, such as growth rate constant (k), maximum heat power (Pmax), inhibition ratio (I), and half inhibition concentration (IC50), were derived from the metabolic power–time curves of S. pombe growth. The half inhibition concentration (IC50) of the ligand was calculated to be 2.58 × 10−3 mol L−1. The complex could strongly influence the lag phase of S. pombe. [ABSTRACT FROM AUTHOR]

A Valen Schiff-base ligand [1,5-bis(2-hydroxy-3-methoxybenzylidene)thiocarbonohydrazide] and its bismuth(III) complex were synthesized. The compositions and structures of two compounds were characterized by elemental analysis, spectrometry (1HNMR, MS, FT-IR, and UV-visible), chemical analysis, molar conductivity, and TG–DTA analysis. The results showed that the molecular formula of Schiff base and its bismuth(III) complex was C17H18O4N4S (abbreviated as H2L, L = C17H16O4N4S) and [Bi(C17H16O4N4S)Cl·H2O] (abbreviated as [Bi(L)Cl·H2O]), respectively. Furthermore, the thermokinetic properties of the action of Schiff base and its bismuth(III) complex on the growth metabolism of S. pombe were studied by bio-microcalorimetry at 305.15 K. The growth rate constant (k), maximum heat power, generation time, inhibition ratio (I) and half inhibition concentration (IC50), and their quantitative relationship with the concentration were calculated, respectively. Experimental results indicated that both Schiff base and its bismuth(III) complex could inhibit the growth of S. pombe, but the inhibitory effect of Schiff base was stronger than that of the complex. The half inhibition concentrations of Schiff base and its bismuth(III) complex were found to be 4.17 × 10−3 mol L−1 and 6.13 × 10−3 mol L−1, respectively. [ABSTRACT FROM AUTHOR]

In this study, a new Schiff base ligand [2-{[4-amino-5-(3,4,5-trimethoxy-benzyl)-pyrimidin-2-ylimino]-methyl}-6-methoxy-phenol, C22H24N4O5] and its bismuth(III) complex [BiC22H22N4O5Cl] were synthesized using o-vanillin and trimethoprim in anhydrous solvents. Chemical analysis, elemental analysis, spectrum analysis and TG-DSC analysis were employed to characterize the compositions and structures of the two new compounds. In particular, the metabolic thermogenic curves of Schizosaccharomyces pombe (S. pombe) and Helicobacter pylori (H. pylori) cells treated by the two new compounds at different concentrations were monitored by an isothermal microcalorimeter at 32.00 and 37.00 °C, respectively. On the basis of the metabolic thermogenic curves, some important biothermokinetic parameters such as the microbial growth rate constant (k), inhibition ratio (I) and half inhibition concentration (IC50) were estimated. The experimental results indicated that both the Schiff base ligand and its bismuth(III) complex could inhibit the growth metabolism of S. pombe and H. pylori, but the inhibitory abilities of the two compounds were as follows: the Schiff base ligand > the complex for S. pombe and the Schiff base ligand < the complex for H. pylori, respectively. More importantly, the results also found that the Schiff base bismuth(III) complex exhibited bidirectional biological effect and hormesis effect on H. pylori cell line, i.e., the complex can stimulate the growth metabolism of H. pylori at low concentration, while inhibiting its growth at high concentration. [ABSTRACT FROM AUTHOR]

The title complex [(CHN)Bi(ONO)] was synthesized by reaction of 1,10-phenanthroline (phen) and Bi(NO)·5HO. The structure of the complex was characterized by single-crystal X-ray diffraction, IR spectroscopy, and elemental analysis. An advanced solution-reaction isoperibol microcalorimeter was applied to determine the standard molar enthalpies of formation at 298.15 K of the complex and Bi(NO)·5HO, giving -(798.92 ± 5.99) and -(1986.87 ± 0.20) kJ mol, respectively. The biological effect of the complex was evaluated by microcalorimetry on the growth of Schizosaccharomyces pombe ( S. pombe). According to thermogenic curves, the corresponding thermokinetics and thermodynamic parameters were derived. The complex had good bioactivity on the growth metabolism of S. pombe, with the value of IC being 2.8 × 10 mol L. [ABSTRACT FROM AUTHOR]

In this work, a new Schiff base [ N, N′- bis(2-hydroxy-3-methoxyphenylmethylidene)-2,6-pyridinediamine, CHNO] and its bismuth(III) complex [Bi(CHNO)]Cl·2HO were synthesized with o-vanillin and 2,6-pyridinediamine in ethanol and THF solvent, respectively. The compositions and structures of the two synthetic compounds were characterized by elemental analysis, chemical analysis, spectrum analysis (including MS, FT-IR, NMR, and UV-Vis), and thermogravimetric analysis. The thermogenic curves for the growth metabolism of Helicobacter pylori ( H. pylori) and Schizosaccharomyces pombe ( S. pombe) treated by different concentrations of the two synthetic compounds were determined by isothermal heat conduction microcalorimetry at 37.00 and 32.00 °C, respectively. Based on the thermogenic curves, some important thermokinetic parameters including the microbial growth rate constant ( k), inhibition ratio ( I), and half inhibition concentration (IC) were calculated. The obtained results revealed that the Schiff base stimulated the growth of H. pylori, while the complex inhibited its growth. By contrast, both the Schiff base and the complex inhibited the growth of S. pombe, but the inhibitory effect of the complex was stronger than that of the Schiff base. [ABSTRACT FROM AUTHOR]

Objective: Chronic stress is an important risk factor for atherosclerotic diseases. Our previous studies have shown that chronic unpredictable mild stress (CUMS) accelerates atherosclerosis and up-regulates TLR4/NF-κB expression in apoE-/- mice. However, TLR4/NF-κB signaling whether directly contributes to the development of atherosclerosis in CUMS mice is unclear. We hypothesized that the interference of TLR4/NF-κB can ameliorate CUMS-induced inflammation and atherosclerosis in apoE-/- mice. Methods: ApoE-/- mice were exposed to 12 weeks CUMS. Ad-siRNA TLR4 was given by tail vein injection (10 μl/mouse, every 5 days), and PDTC (an inhibitor of NF-κB) was given by intraperitoneal injection (60 mg/kg, once a day). Plasma corticosterone concentrations were determined by solid-phase 125I radioimmunoassay. Atherosclerosis lesions in aortic sinuses were evaluated and quantified by IMAGEPRO PLUS. Western blotting was used to detect the expression of TLR4, NF-κB, and IL-1β in aortas of the mice. Plasma lipid profiles, IL-1β, TNF-α, and MCP-1 were measured by ELISA. Results: Our results indicated that CUMS apoE-/- mice treatment with siRNA TLR4 significantly decreased atherosclerosis and down-regulated TLR4, NF-κB, and inflammatory cytokines. PDTC also remarkably reduced atherosclerosis and the levels of IL-1β, TNF-α and MCP-1 in plasma. However, Treatment with siRNA TLR4 or PDTC had no effect on plasma corticosterone levels, and lipid profiles. Conclusions: TLR4/NF-κB pathway may participate in CUMS-induced atherosclerosis through activation of proinflammatory cytokines in apoE-/- mice. Our data may provide a new potential therapeutic target for prevention of CUMS -induced atherosclerosis. [ABSTRACT FROM AUTHOR]

A copper(II) Schiff-base complex [CuL·2MeOH·HO] was prepared by reaction of the ligand [HL = N, N′- o-phenylene-bis(3-methoxysalicylideneimine)] and Cu(OAc)·HO in methanol at 328.15 K. X-ray diffraction analysis revealed that the title complex was crystallized in the triclinic crystal system with space group P-1, in which copper(II) ion was located in the NO ligand binding sites. According to two designed thermochemical cycles, the dissolution enthalpies of relevant substances of two reactions in the calorimetric solvents were determined by a solution-reaction isoperibol calorimeter, respectively. Combined with some other auxiliary thermodynamic data, the standard molar enthalpies of formation of the ligand and the complex were calculated to be: $$ \Delta_{\text{f}} H_{\text{m}}^{\theta } $$ [HL(s), 298.15 K] = −(384.2 ± 9.10) kJ mol and $$ \Delta_{\text{f}} H_{\text{m}}^{\theta } $$ [CuL·2MeOH·HO (s), 298.15 K] = −(1072.6 ± 9.2) kJ mol. [ABSTRACT FROM AUTHOR]

o-Vanillin and trimethoprim are two main raw materials for the synthesis of Valen Schiff bases which have been proved to possess established biological activities and may be used as the antibacterial agent candidates. The standard molar enthalpy of combustion and the standard molar enthalpy of formation of a substance are some of the most fundamental thermodynamic properties, and closely related to other physical, biological, physiological, and chemical properties. However, up to now, no reports about those thermodynamic properties of the title compounds were found in literatures. In this paper, the constant-volume energies of combustion of o-vanillin and trimethoprim at T = 298.15 K and p = 3.01 MPa were measured by a precision oxygen-bomb combustion calorimeter to be Δ U [ o-vanillin(s), 298.15 K] = −(24,971.89 ± 22.02) J g and Δ U [trimethoprim(s), 298.15 K] = −(26,366.77 ± 21.96) J g, respectively. According to the definition of combustion enthalpy, the standard ( p = 0.1 MPa) molar enthalpies of combustion of o-vanillin and trimethoprim were determined to be $$ \Delta_{\text{c}} H_{\text{m}}^{\varTheta } $$ [ o-vanillin(s), 298.15 K] = −(3,800.55 ± 3.35) kJ mol and $$ \Delta_{\text{c}} H_{\text{m}}^{\varTheta } $$ [trimethoprim(s), 298.15 K] = −(7,657.05 ± 6.38) kJ mol, respectively. Finally, the standard ( p = 0.1 MPa) molar enthalpies of formation of o-vanillin and trimethoprim were calculated to be $$ \Delta_{\text{f}} H_{\text{m}}^{\varTheta } $$ [ o-vanillin(s), 298.15 K] = −(490.85 ± 3.51) kJ mol and $$ \Delta_{\text{f}} H_{\text{m}}^{\varTheta } $$ [trimethoprim(s), 298.15 K] = −(424.56 ± 6.64) kJ mol from a combination of the experimental values of enthalpies of combustion and some other auxiliary thermodynamic data through a designed thermochemical cycle based on a supposed chemical reaction. [ABSTRACT FROM AUTHOR]

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The product, [Pr(CHO)(CHNO)], which was formed by praseodymium nitrate hexahydrate, salicylic acid (CHO), and 8-hydroxyquinoline (CHNO), was synthesized and characterized by elemental analysis, UV spectra, IR spectra, molar conductance, and thermogravimetric analysis. In an optimalizing calorimetric solvent, the dissolution enthalpies of [Pr(NO)·6HO(s)], [2 CHO(s) + CHNO(s)], [Pr(CHO)(CHNO)(s)], and [solution D (aq)] were measured to be, by means of a solution-reaction isoperibol microcalorimeter, $$ \begin{gathered}\Updelta_{\text{s}} H_{\text{m}}^{\theta}\left[ {{ \Pr }\left( {{\text{NO}}_{ 3} } \right)_{ 3} \cdot 6{\text{H}}_{ 2} {\text{O}}\left( {\text{s}} \right), 2 9 8. 1 5{\text{ K}}} \right] \, = - ( 20. 6 6 { } \pm \, 0. 29)\,{\text{kJ}}\,{\text{mol}}^{ - 1} , \hfill \\\Updelta_{\text{s}} H_{\text{m}}^{\theta } \left[ { 2 {\text{C}}_{7} {\text{H}}_{ 6} {\text{O}}_{ 3} \left( {\text{s}} \right) +{\text{ C}}_{ 9} {\text{H}}_{ 7} {\text{NO}}\left( {\text{s}}\right),{ 298}. 1 5 {\text{ K}}} \right] \, = \, ( 4 2. 2 7 { }\pm \, 0. 3 1)\,{\text{kJ}}\,{\text{mol}}^{ - 1} , \hfill \\\Updelta_{\text{s}} H_{\text{m}}^{\theta } \left[ {{\text{solutionD }}\left( {\text{aq}} \right), 2 9 8. 1 5 {\text{ K}}} \right] \,= - \left( { 8 9. 1 5 { } \pm \, 0. 4 3}\right)\,{\text{kJ}}\,{\text{mol}}^{ - 1} , \hfill \\\end{gathered} $$ and $$ \Updelta_{\text{s}} H_{\text{m}}^{\theta } \left\{ {\left[ {{\Pr }\left( {{\text{C}}_{ 7} {\text{H}}_{ 5} {\text{O}}_{ 3} }\right)_{ 2} \left( {{\text{C}}_{ 9} {\text{H}}_{ 6} {\text{NO}}}\right)} \right]\left( {\text{s}} \right),{ 298}. 1 5 {\text{ K}}}\right\} \, = - \left( { 4 1.0 4 { } \pm \, 0. 3 3}\right)\,{\text{kJ}}\,{\text{mol}}^{ - 1} $$ , respectively. Through an improved thermochemical cycle, the enthalpy change of the designed coordination reaction was calculated to be $$\Updelta_{\text{r}} H_{\text{m}}^{\theta} = \, ( 2 1 3. 1 8\pm0. 6 9)\,{\text{kJ}}\,{\text{mol}}^{ - 1} $$ , the standard molar enthalpy of the formation was determined as $$ \Updelta_{\text{f}} H_{\text{m}}^{\theta} \left\{ {\left[ {{\Pr }\left( {{\text{C}}_{ 7} {\text{H}}_{ 5} {\text{O}}_{ 3} }\right)_{ 2} \left( {{\text{C}}_{ 9} {\text{H}}_{ 6} {\text{NO}}}\right)} \right]\left( {\text{s}} \right), 2 9 8. 1 5 {\text{K}}}\right\} \, = \, - \, ( 1 8 7 5. 4\pm 3.1)\,{\text{kJ}}\,{\text{mol}}^{ - 1} $$ . [ABSTRACT FROM AUTHOR]