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In the field of piezoelectric applications, perovskite-based multifunctional composite ceramics are widely explored. The morphotropic phase boundary (MPB) regions, where dual structural phases coexist, play a crucial role in boosting the ferroelectric and piezoelectric properties significantly. Herein, MPB-region-existent 0.7BiFeO3-0.3BaTiO3 (BFBT) composite ceramic is investigated under the influence of wt%Sn-ion incorporation at the lattice sites of the BFBT. Specifically, the ceramic composition BFBT:0.2Sn has demonstrated excellent remnant polarization (Pr ~ 22.68 µC/cm2), an impressive piezoelectric coefficient (d33 ~ 211 pC/N), stable impedance of 1.07 × 107 Ω, a Curie temperature of 435 °C and low dielectric loss (tanδ) of <0.5. Moreover, the BFBT:0.2Sn ceramic has also maintained a stable d33 of ~150 pC/N and resistivity of ~102 Ω even at a temperature of 400 °C. Such outcomes confirm the ability and potential of the BFBT:0.2Sn ceramic composition for high-temperature piezoelectric applications. [ABSTRACT FROM AUTHOR]

Bismuth layered structure ferroelectrics (BLSFs), also known as Aurivillius phase materials, are ideal for energy-efficient applications, particularly for solar cells. This work reports the first comprehensive detailed theoretical study on the fascinating structural, electronic, and optical properties of XNb2Bi2O9 (X = Ca, Ba, Be, Mg, Sr). The Perdew–Burke–Ernzerhof approach and generalized gradient approximation (GGA) are implemented to thoroughly investigate the structural, bandgap, optical, and electronic properties of the compounds. The optical conductivity, band topologies, dielectric function, bandgap values, absorption coefficient, reflectivity, extinction coefficient, refractive index, and partial and total densities of states are thoroughly investigated from a photovoltaics standpoint. The material exhibits distinct behaviors, including significant optical anisotropy and an elevated absorption coefficient > 105 cm−1 in the region of visible; ultraviolet energy is observed, the elevated transparency lies in the visible and infrared regions for the imaginary portion of the dielectric function, and peaks in the optical spectra caused by inter-band transitions are detected. According to the data reported, it becomes obvious that XNb2Bi2O9 (X = Ca, Ba, Be, Mg, and Sr) is a suitable candidate for implementation in solar energy conversion applications. [ABSTRACT FROM AUTHOR]

The monoazo substituted five membered heterocycles, along with their seleno like moieties are still of interest in organic chemistry due to their medicinal and valuable applications. In continuation of our interest in the study of heterocyclic azo compounds containing sulphur and / or nitrogen heteroatoms, the synthesis of 5-aryl mono azo-thiazol-2-ylcarbamoyl-thiophene along with their seleno like derivatives of pyridine, pyridazine and quinolone, were accomplished. All the synthesized compounds were in vitro screening of their antioxidant activity, antitumor activity against Ehrlich ascites carcinoma cell EACC cell line and antimicrobial activity against various pathogenic microorganisms, such as Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Salmonella typhimurium) and fungi strains of Aspergillus flavus and Candida albicans. The structural–activity relationship was studied based on the obtained data.

Introduction Animal models of human diseases and disorders have gained increasing importance. These models serve give us a glimpse into the mechanisms of these diseases, test new therapeutic strategies, and [...], We performed this study to understand the effect of human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) on the submandibular gland after bilateral ovariectomy. For this, 21 adult female rats were distributed equally among 3 groups: the sham-operated group (SHAM); the ovariectomized group (OVX); and the OVX group that received repeated intravenous injections of the hUCB-MSCs (OVX + hUCB-MSCs). We used reverse transcription--PCR to analyze for the gene expression of AQPs 3, 4, 5, and BMP-6. The cellular localization and expression of human CD105, human CD34, proliferating nuclear antigen (PCNA), single-stranded DNA (ss-DNA), caspase 3, AQP1, and [alpha] smooth muscle actin ([alpha]-SMA) were determined immunohistochemically. In the OVX group, a significant decrease in the gene expression of AQP3, AQP4, and BMP6, as well as the acinar area % was detected, while area % of granular convoluted tubules (GCTs) showed a significant increase. A significant decrease in area % staining positively for AQP1 and [alpha]-SMA was noted. An obvious improvement in the structure of the submandibular gland was demonstrated in the group injected with hUCB-MSCs, as well as a significant increase in the gene expression of AQP3, AQP4, and BMP6. The acinar and GCT area %, as well as the different measured markers, were relatively normal. This demonstrates that E2-deficiency induces structural changes to the submandibular gland. Moreover, a definite amelioration of the structure and function of the submandibular gland was detected after the administration of hUCB-MSCs. Key words: submandibular gland, ovariectomy, UCB-MSCs, female rat. Afin d&apos;examiner l&apos;effet des cellules souches mésenchymateuses humaines (CSMh) de sang de cordon ombilical sur la glande sous-maxillaire après une ovariectomie bilatérale, 21 rates adultes ont été réparties également en trois groupes : groupe chirurgie fictive, groupe avec ovariectomie (OVX) et le groupe OVX ayant reçu des injections intraveineuses répétées de CSMh du sangde cordon ombilical (OVX + CSMh de sangde cordon ombilical). L&apos;expression des aquaporines (AQP) 3, 4 et 5 et de la protéine morphogénétique osseuse 6 (BMP-6) a été analysée par RT-PCR. La localisation cellulaire et l&apos;expression du CD105 humain, du CD34 humain, de l&apos;antigène nucléaire de prolifération cellulaire (PCNA), de l&apos;ADN simple brin (ADNsb), de la caspase 3, de l&apos;AQP1 et de l&apos;actine de muscle lisse [alpha] ([alpha]-SMA) ont été déterminées par immunohistochimie. Chez le groupe OVX, une diminution significative de l&apos;expression génique de l&apos;AQP3, de l&apos;AQP4 et de la BMP6 de même que du pourcentage de la superficie acinaire a été détectée, alors que le pourcentage de la superficie occupée par les tubules contournés granulaires était significativement accru. Une diminution significative du pourcentage de la superficie colorée positivement quant à l&apos;expression de l&apos;AQP1 et de l&apos;[alpha]-SMA était notée. Une augmentation significative de l&apos;expression génique de l&apos;AQP3, de l&apos;AQP4 et de la BMP6 et une amélioration évidente de la structure de la glande sous-maxillaire ont été démontrées chez le groupe ayant reçu une injection de CSMh de sang de cordon ombilical. Le pourcentage des superficies acinaire et des tubules contournés granulaires de même que les différents marqueurs mesurés se situaient près de la normale. En conclusion, la déficience en E2 induit véritablement des modifications structurales de la glande sous-maxillaire. De plus, une amélioration claire de la structure et de la fonction de la glande sous-maxillaire est détectée à la suite de l&apos;administration de CSMh de sang de cordon ombilical. [Traduit par la Rédaction] Mots-clés: glande sous-maxillaire, ovariectomie, CSMh de sang de cordon ombilical, rat femelle.

Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene–aldehyde compound. Different xanthene concentrations (ca. 0.1–2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds' adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced. [ABSTRACT FROM AUTHOR]

Convenient domino protocol was developed for the synthesis of 2‐arylquinazolin‐4‐amines by the reaction of N‐(2‐cyanophenyl) substituted benzimidoyl isothiocyanates with isopropyl amine. The major advantages of this protocol are short reaction times, mild conditions, simple work up, high yields, and pure products. The efficacy of this protocol owes to the competence of synthesis, pure isolation of imidoyl isothiocyanates, and the unique structure conformation of the corresponding intermediate thiourea derivatives. [ABSTRACT FROM AUTHOR]

Herein, a novel carbon paste electrode incorporated with reduced graphene oxide (rGO) was electrochemically characterized for sensitive adsorptive voltammetric determination of oxfendazole (OXF) in veterinary formulations and spiked milk samples. On the electrode surface, oxfendazole showed a reversible electrooxidation behavior through a mixed adsorption-diffusion with the involvement of one-electron on the electroanalytical measurements and molecular orbital studies. Linear calibration curves were constructed within OXF concentration ranged from 1.75 to 1890.9 ng ml-1 with LOD value of 0.85 ng ml-1. Compared with the reported OXF sensor, the rGO based sensors showed improved sensitivity with measurement reproducibility and long operational lifetime and shelf lifetime. The fabricated sensors were applied for the quantification of oxfendazole in the local veterinary formulations and spiked milk samples with high accuracy and precision compared with the traditional spectrophotometric techniques. [ABSTRACT FROM AUTHOR]

Here, we synthesized new thiazole complexes from Cu (II), Fe (III), and Pd (II) ions. Such complexes were characterized to present their chemical formulae, firstly. The octahedral geometry was suggested for the investigated complexes except Pd (II) complex (ARPTPd), which has a square‐planer arrangement. ARPTPd was planned to be used as a catalyst for synthesis of dihydrotetrazolo[1,5‐a]pyrimidine derivatives at mild conditions. The catalytic activity of ARPTPd complex in four‐components reaction approach was deliberately monitored till it reaches the most favorable conditions. The advantages of suggested catalyst were basically summarized by using green solvent (H2O), lower reaction time, and high products yields. Also, the superiority of ARPTPd complex and ultrasonic irradiation towards synthesis of dihydrotetrazolo[1,5‐a]pyrimidine derivatives was revealed compared with other Lewis acids, basic, and ionic liquid catalysts. Furthermore, the mildness of conversion and compatibility with different functional groups makes it attractive. In addition, in consecration, computational aspects were often taken according to their effect on the declaration or discrimination of variable functional characteristics. Crystal packing systems of complexes were configured to extract important surface properties. DFT study was also applied to explain the causes behind the superiorly of ARPTPd complex. Also, the optimization process for intermediates was executed to support the suggested mechanism. Finally, this simple, economical, and green catalytic procedure may be applied to the industry in future. [ABSTRACT FROM AUTHOR]

Three novel Pd (II), Cu (II), and Fe (III) complexes were prepared from thiazole ligand through bidentate chelating mode. Alternative spectral and analytical tools were applied to elucidate their structural and molecular formulae. This study was extended to investigate stability and stoichiometry of complexes in solution, using standard methods. In addition, the best atomic distribution within structural forms was obtained by Material Studio Package via the density functional theory (DFT) method. This computational study fed us with significant physical characteristics for differentiation. Also, crystal surface properties in the packing system were studied using the Crystal explorer program, to evaluate the extent of contact between surfaces. Computational data discriminate Pd (II)‐thiazole (HYHPd) complex by some physical features, which may be promising in the catalytic field. This complex was selected to play a catalytic function to synthesize polyfunctionalized pyrrole derivatives using ultrasonic irradiation in a one‐pot reaction. The catalyst was selected for this application based on the history of Pd (II) complexes and the properties expected theoretically. A condensation reaction for aromatic aldehyde, aromatic amine, acetylacetone, and nitromethane was carried out under mild reaction conditions by ultrasonic irradiation. All reaction conditions were optimized among that variable Lewis acid catalysts in comparison to our new complexes. HYHPd catalyst displayed superiority in overall trials with high yield, short time, and green conditions (solvent H2O/EtOH). Also, the recovery of hetero‐catalyst was succeeded and reused by the same efficiency up to five times after that the efficiency was reduced. The mechanism of action was proposed based on the ability of Pd (II) for adding extra‐bonds over z axis and supported by theoretical aspects. [ABSTRACT FROM AUTHOR]

A simple method for the preparation of multifunctional nanocomposite was developed towards the production of water‐repellent, electrically conductive, and photoluminescent film onto cotton fibres. The nanocomposite was composed of lanthanide‐doped strontium aluminium oxide and silicon rubber dispersed in petroleum ether. The electrically conductive fabric was woven from nickel strips twisted with cotton filaments as core yarns, which were wrapped with pure cotton yarns. The nanoparticles (NPs) of lanthanide‐doped strontium aluminium oxide were mixed with environmentally friendly room‐temperature vulcanizing silicon rubber (RTV‐SR) dissolved in petroleum ether to give the silicon rubber/strontium aluminate nanocomposites. The produced nanocomposites were applied onto electrically conductive cotton/nickel fibres using spray‐coating technology. The surface of the cotton/nickel fibres showed different hierarchical morphologies depending on the total content of the silicon rubber. Additionally, the superhydrophobic effect was found to be improved upon increasing the total content of the luminescence pigment NPs. The morphologies of the prepared phosphor NPs were determined using transmission electron microscopy (TEM). The generated transparent luminescence film demonstrated an absorbance peak at 358 nm and an emission peak at 515 nm. Photoluminescence of cotton fibres was monitored with the generation of different colours, including grey, green‐yellow, bright white, and turquoise shades as recognized using CIE Laboratory colorimetric parameters. The emission, excitation, lifetime, and decay time spectra of the phosphorescent spray‐coated cotton samples were studied. The surface morphologies and chemical compositions of the spray‐coated cotton/nickel were investigated using wavelength‐dispersive X‐ray fluorescence (WD‐XRF), scanning electron microscope (SEM), Fourier‐transform infrared spectra (FTIR), and energy‐dispersive X‐ray analyzer (EDAX). The superhydrophobic effects were characterized by measuring static water contact angle. The comfort characteristics of the treated cotton/nickel substrates were assessed by investigating their air permeability and stiffness. The treated cotton/nickel fabrics also displayed an antimicrobial activity. The results displayed water repellence with high electrical conductivity and photoluminescence properties. [ABSTRACT FROM AUTHOR]

We have designed a series of quinoxalinepeptidomimetic derivatives based on our previously reported scaffold in an attempt to find a promising lead compound. Quinoxalinepeptidomimetic derivatives, N-alkyl-3-(4-allyl-3-oxo-3,4-dihydro-quinoxalin-2-yl)propanamides, methyl 2-[3-(4-allyl-3-oxo-3,4-dihydro-quinoxalin-2-yl)propanamido] alkanoates, and their O-regioisomers, were prepared via the competing alkylation reaction of the ambient nucleophile, methyl 3-(3-oxo-3,4-dihydroquinoxalin-2-yl)propanoate, with allyl bromide to afford the corresponding O- and N-allyl quinoxaline ester derivatives. The esters gave the desired products through reactions with amines and amino acid esters via the azide coupling method. We have examined the antiproliferative activities of the 34 different synthesized compounds using human HCT-116 and HEH-293 cell lines. Out of 34 screened derivatives, 22 active compounds exhibited inhibitory action against the HCT-116 cells, with IC50 values ranging from 0.11 mg ml−1 to 0.78 mg ml−1. We also examined the impact of these active compounds on cancer cell nuclei and caspase 3 activity; we found that the active compounds also increased the caspase 3 activity, which led to the programmed cell death of cancer cells. We also examined the impact of 34 compounds on normal and non-cancerous cells (HE-293) and we found that these active compounds did not have any cytotoxic effects on normal cells. [ABSTRACT FROM AUTHOR]

Novel series of benzimidazole derivatives are developed based on the key compound 2‐mercaptomethyl benzimidazole 1. The reactivity of the precursor compound 1 towards nucleophilic reagents enabled us to produce new series with expected bioactivity. The synthesized benzimidazole scaffolds are structurally authenticated and fully characterized by their spectral properties. They exhibit antimicrobial efficiency against selected pathogenic bacteria strains (Gram +ve & ‐ve bacteria) using disc diffusion method, the inhibition clear zones (mm) and MIC are recorded as well. The compounds are also assessed for their cytotoxicity, antioxidant and antitumor activity against HEP−G2 human hepatoma cell line, showing gradient efficiencies related to the chemical structure. [ABSTRACT FROM AUTHOR]

Thiophenes are a highly important group of heterocycles and have been of great interest to researchers due to their various reactivities. Many synthetic strategies are used to generate functionalized thiophene derivatives. Several reactions are described, depending on the reactivity of the substituents attached to the thiophene nucleus toward different nucleophiles to yield the versatile thiophene products. Many diverse applications have been utilized for thiophenes from medicinal chemistry to material science. [ABSTRACT FROM AUTHOR]

Synthesis of some new mono azo organic compounds, based on 1‐arylazo‐2‐naphthol nucleus is performed by diazo‐coupling strategy of β‐naphthol with different 1ry aromatic amines. Interestingly, the monoazo products undergo functionalized reactions to obtain the target azo naphthol derivatives (3–14). The synthesized dyes are conjugated with gold and/ or silver nanoparticles by electrostatic interaction. Photodynamic therapeutic efficiencies of the synthesized naphthol azo dyes and their conjugates have been evaluated against promyelocytic leukemia cell lines (HL‐60) in dark and light conditions. Dye‐Nanometal conjugates act as photosensitizers (PSs) exhibiting an enhancement of the optical properties as well as in photodynamic therapeutic efficiencies in variable degrees depending on dye structure. [ABSTRACT FROM AUTHOR]

Various novel benzimidazole entities linked to pyrazolyl and hydrazonoyl cyanide substrates carrying aryl and heteroaryl groups (8a–e to 10a–e) were synthesized using new route syntheses and were focused on their pharmacological evaluation as one of the most important factors for the determination of the activity of these synthesized compounds. The obtained benzimidazoles' series were fully characterized and exhibited remarkable pharmacological activity upon in vitro screening for their antibacterial activity against strains of selected pathogenic Gram‐positive bacteria (Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli) comparing with Ampicillin and Kanamycin as standard antibacterial agents and against human liver cancer cell lines (HepG2) as antitumor agents as well. [ABSTRACT FROM AUTHOR]

Considering pteridine as a worthy structure for improving probes of magnificent therapeutic potentials, some new pteridine conjugates were synthesized by aminomethylation of benzopteridinethione with a variety of primary aromatic amines and formaldehyde solution (37%) through the Mannich reaction. The proposed mechanism of formation of the synthesized compounds was discussed, and the structure of the newly synthesized compounds was elucidated on the basis of their IR, 1H NMR, 13C NMR, mass spectral, and elemental analyses. Furthermore, some selected compounds were evaluated in vitro for their antimicrobial activities; the preliminary data stated that the majority of the tested compounds exhibited significant antimicrobial activity. Analogues 22, 23, 20, 19, 24, and 15 were found to be the most potent against all the tested microorganisms. [ABSTRACT FROM AUTHOR]

Introduction: Cardiac diseases can affect the contractile and/or conductive cardiac muscle cells. Recently, the microscopic examination of the subendocardial biopsy is being used in the diagnosis of some cardiac lesions. However, the routine staining cannot differentiate between different types of cardiac fibers. Aim of the work: The present study aims to illustrate the use of anti-cardiac troponin-T3 (cTnT3) immunostaining as a recent tool to distinguish between the contractile and conducting fibers. Materials and Methods: Specimens from both left ventricular wall and interventricular septum were obtained from 6 healthy adult male mice. These specimens were fixed in 4% paraformaldehyde at 4⁰C and processed for paraffin sections. Then, 3 μm thick sections were stained with H&E and anti-cTnT3 antibody and were examined under light microscope. The optical density of the cTnT3 staining affinity of the cardiac fibers was measured morphometrically and the values were statistically analyzed. Results: Examination of H&E stained sections of the left ventricular wall and interventricular septum revealed homogenous staining of all cardiac fibers with an undetectable difference among them. While examination of the immunostained sections with anti-cTnT3 revealed different affinities: the majority of fibers expressed high-positive staining affinity while other fibers had a low or no staining affinity. The high-positive staining affinity was in the form of cytoplasmic transverse dark brownish striations in longitudinally oriented cardiac fibers. The fibers which expressed a low or no staining affinity were either singly scattered especially in the left ventricular wall or grouped in the subendocardial regions of the interventricular septum. Statistically, the optical density values of a low or no staining affinity cardiac fibers were significantly lower (2.5±0.01) than high positive staining affinity cardiac fibers (3.04±0.19). Conclusion: Immunostaining with anti-cTnT3 staining could be added to the routine staining in the examination of cardiac biopsies. [ABSTRACT FROM AUTHOR]