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Most frequently affecting women and those with diabetes, urinary tract infections (UTI) are a prevalent illness. Inappropriate management of the acute stage of the illness leads to pyelonephritis, which makes the condition chronic. Multiple medications are ineffective against the microorganisms that cause UTIs, due to multi-drug resistance. Escherichia coli fimbria contains the bacterial adhesin protein FimH, which is responsible for adhering bacteria to the host urinary tract's epithelial cells. Therefore, FimH becomes a crucial target for the development of drugs since it plays a key role in bacterial infections like UTIs. In the context, phytochemical intervention using Garcinia indica (Kokum) and Vaccinia macrocarpon (Cranberry) proves to be an effective alternative. Garcinia indica is a tropical plant endemic to India, particularly in the Karnataka, Kerala, and Maharashtra coastal regions. The fruit is abundant in anthocyanins and benzophenones, which have antibacterial properties against a variety of pathogens. Because the fruit includes antiadhesive flavonoids and proanthocyanins, Vaccinia macrocarpon fruit syrup is currently utilized as a treatment for UTIs and the fruit is native to America. The current study contrasts the inhibitory effects of secondary metabolites from Vaccinia macrocarpon and Garcinia indica on E. coli FimH protein. According to the study, garcinol and kaempferol from the plants’ Garcinia indica and Vaccinia macrocarpon, respectively, showed the highest affinities for the protein FimH.

Using the analysis of the temperature and field dependence of the magnetization measurements, the H-T phase diagram, tricritical point and exchange constants of the antiferromagnetic (AFM) MnTa2O6 are determined in this work. Temperature dependence of magnetic susceptibility χ(T) yields the Néel temperature TN = 5.97 K determined from the peak in the ∂(χT)/∂T vs. T plot, in agreement with the TN = 6K determined from the peak in the Cp vs. T data. The experimental data of Cp vs. T near TN is fitted to Cp = A|T-TN|-α yielding the critical exponent α = 0.09 (0.13) for T > TN (T < TN). The χ-T data for T > 25 K fits well with the modified Curie-Weiss law: χ = χ0 + C/(T-θ) with χ0 = -2.12 × 10-4 emu.mol-1Oe-1 yielding θ = -24 K, and C = 4.44 emu.K.mol-1Oe-1, the later giving μ= 5.96 μB per Mn2+. This yields the effective spin S = 5/2 and g = 2.015 for Mn2+, in agreement with g = 2.0165 measured using ESR spectroscopy. Using the magnitudes of θ and TN and molecular field theory, the AFM exchange constants J0/kB = -1.5 ± 0.2 K and J⊥/kB = -0.85 ± 0.05 K for Mn2+ ions along the chain c-axis and perpendicular to the c-axis respectively are determined. The χ-T data when compared to the prediction of a Heisenberg linear chain model provides semiquantitative agreement with the observed variation. The H-T phase diagram is mapped using the M-H isotherms and M-T data at different H yielding the tricritical point TTP (H, T) = (17.0 kOe, 5.69 K) separating the paramagnetic, AFM, and spin-flop phases. At 1.5 K, the experimental magnitudes of the exchange field HE = 206.4 kOe and spin-flop field HSF = 23.5 kOe yield the anisotropy field HA = 1.34 kOe.

This work presents the magnetic field-temperature (H-T) phase diagram, exchange constants, specific heat (C P ) exponents and magnetic ground state of the antiferromagnetic MnNb 2 O 6 polycrystals. Temperature dependence of the magnetic susceptibility χ (= M/H) yields the Néel temperature T N = 4.33 K determined from the peak in the computed ∂(χT)/∂T vs T plot in agreement with the transition in the C P vs T data at T N = 4.36 K. The experimental data of C P vs T near T N is fitted to C P = A|T − T N | −α yielding the critical exponent α = 0.12(0.15) for T > T N (T < T N ). The best fit of χ vs T data for T > 50 K to χ = χ 0 + C/(T − θ) with χ 0 = −1.85 × 10 −4 emu mol −1 Oe −1 yields θ = −17 K, and C = 4.385 emu K mol −1 Oe −1 , the latter giving magnetic moment μ = 5.920μ B per Mn 2+ ion. This confirms the effective spin S = 5/2 and g = 2.001 for Mn 2+ and the dominant exchange interaction being antiferromagnetic in nature. Using the magnitudes of θ and T N and molecular field theory (MFT), the exchange constants J 0 /k B = −1.08 K for Mn 2+ ions along the chain c-axis and J ⊥ /k B = −0.61 K as the interchain coupling perpendicular to c-axis are determined. These exchange constants are consistent with the expected χ vs T variation for the Heisenberg linear chain. The H-T phase diagram, mapped using the M-H isotherms and M-T data at different H combined with the reported data of Nielsen et al, yields a triple-point T TP (H, T) = (18 kOe, 4.06 K). The spin-flopped state above T TP and the forced ferromagnetism for H > 192 kOe are used to estimate the anisotropy energy H A ≈ 0.8 kOe.

A comprehensive study on the mechanism of ac-charge transport and dielectric relaxation in the MnNb2O6 Columbite system has been reported. Thermally driven, Arrhenius-like behavior of the ac-conductivity (σ(ω,T)) is predominant at temperatures above 300 K in the frequency range 50 Hz to 5 MHz with activation energies (Eac) lying between 0.45 and 0.38 eV. Besides, a quadratically decreasing trend in the activation energy is evident as given by: Eac(f) = A + B f + C f 2 with the constants A (0.413 eV), B (0.023 eV/Hz) and C (-0.004 eV/Hz2). The measured σ(ω,T) data is analyzed using the Double power law to explain the dispersive behavior of electrical conductivity. These studies also provide evidence for the correlated-barrier hopping (CBH) conduction mechanism of charge carriers for temperatures in the range 173 K to 473 K. Further, the temperature dependence of frequency exponent, s(T) displays two distinct regions both of which are associated with the CBH mechanism. However, the second region is more dominated by thermally activated Arrhenius-like behavior. The dynamical response of complex electric modulus spectra (M*(ω,T)) and the corresponding analysis using Kohlrausch-Williams-Watts method reveals the presence of a non-Debye type relaxation process with decay function exponent β lying between 0.794 and 0.840. This inference of the non-Debye type relaxation process is further supported by depressed semicircles in Nyquist plots and the higher magnitude of FWHM (~ 1.44 decades) of the normalized master cusp (M′′/M′′max vs. ω/ωmax) compared to the FWHM (= 1.14 decades) for ideal Debye behaviour. Both short-range and long-range conductivity regions are ubiquitous in M*(ω,T) with a pronounced distribution of relaxation times (τ ~ 935.8 - 0.36 μs) with temperature. This study further leads to the estimation of activation energy of charge carriers, Em = 0.44 eV which is in consonance with Eac(f,T).