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Aluminum can be found in water and vegetables in the form of the trivalent ion (Al3+), which can potentially contaminate food and water. Overconsumption of aluminum can lead to serious health problems in humans. Therefore, there is a need for an economical and simple procedure to detect the presence of aluminum. In this study, we synthesized a conjugate of Grewia asiatica extract with silver nanoparticles. The nanoparticle-stabilized fruit extract of Grewia asiatica was found to be an extremely selective sensor of Al3+ in tap water, DI water, industrial wastewater, and human blood plasma. We characterized the Grewia asiatica-conjugated silver nanoparticles (GA-AgNPs) using UV-visible, SEM, and AFM techniques and found that they were stable in an extensive pH range and different electrolyte concentrations up to 10 M NaCl. The GA-AgNPs were circular in shape with typical particle sizes of 65–97 nm. We inspected the photo physical properties of GA-AgNPs concerning metallic ions using UV-visible spectroscopy and found that they were highly selective for Al3+ ions, with no interfering ions detected in competitive experimentation. The absorption intensity of GA-AgNPs was directly related to Al3+ concentration over a wide range of concentrations (6.25–500 μM). Jobs plot experiment displayed 1 : 1 binding stoichiometry between GA-AgNPs, and Al3+. Additionally, GA-AgNPs were effectively utilized for the recognition of Al3+ in laboratory tap water, DI water, industrial wastewater, and human blood plasma.

In this communication we have studied well known physical process of two-dimensional advection–diffusion phenomena. The advection–diffusion equation is time-fractionalized by exploiting Atangana-Baleanu fractional derivative operator. This fractionalization is achieved in the generalized constitutive equation of the mass flux density vector. The fractionalized two-dimensional advection–diffusion equation turns out to be a two-dimensional nonlinear fractional partial differential equation. This partial differential equation is considered under the hypothesis of an initial concentrated loading and Robin type boundary conditions. The analytical expression of the solution is determined for this boundary value problem by employing the integral transforms method, namely, the Laplace transform, sine-Fourier transform and finite sine–cosine Fourier transform. The effects of fractional parameter α on the concentration obtained from the analytical solution, for various parameters of interest, are illustrated graphically with the help of software Mathcad. The graphs illustrate that the memory effects are remarkable for small values of time and ordinary for large values of the time.

Mass, energy, and momentum transfer processes between fluid-saturated porous media and the adjacent free flow occur in many natural and technical systems. The flow dynamics in the porous region and the adjacent free flow is strongly controlled by the mechanisms at the common interface and conditions on the outer surface of the free-flow. The present paper considers unsteady axisymmetric flows of viscous fluids through an annular domain with a porous layer covering a cylindrical solid core. Fluid flow in the domain filled with porous material and in transparent domain is described by Brinkman model and Navier Stokes equations, respectively. Analytical solutions for the dimensionless velocity fields in the Laplace domain are determined using Bessel functions, Laplace transform, and the appropriate interface and boundary conditions. The inversion of the Laplace transforms is done with the help of a numerical algorithm. In addition, the hydrodynamic permeability is determined. The dependence of the dimensionless velocity fields and of hydrodynamic permeability on characteristic parameters of the porous layer is numerically and graphically discussed. Since the velocity on the outer surface is given by an arbitrary function of time, the results in this paper could be used to study various filtration problems.

The unsteady free convection flow, with heat and mass transfer, of an electrically conducting viscoelastic fluid, through a porous medium of variable permeability is investigated. The flow domain is a half space, bounded by a vertical porous plate, with the constant heat flux, constant concentration and a rectilinear translation in its plane with constant velocity. The applied magnetic field of uniform strength is perpendicular to the plate and the magnetic lines of force are fixed relative to plate or, to fluid. Permeability of the porous medium decreases exponentially, with respect to time t, relative to a constant mean value. The closed forms of the temperature, concentration and velocity fields are determined by means of the Laplace transform and method of separation of variables. Numerical calculations are carried out and graphically displayed in order to study the effects of several parameters such as Hartmann number, permeability of porous medium, Prandtl number, heat source/sink parameter, Schmidt number, chemical reaction parameter. The numerical results show that, if the applied magnetic field is fixed to the plate the fluid flows more slowly than if the magnetic field is fixed to fluid. If the magnetic field strength is high, the fluid moves more slowly than into weak magnetic fields. Keywords: Viscoelastic fluid, Free convection, Magnetic field, Porous medium, Variable permeability, MSC2010database: 76A10, 76R10, 76 W05, 76S05

Abstract Objective Large Language Models (LLMs) have revolutionized healthcare, yet their integration in dentistry remains underexplored. Therefore, this scoping review aims to systematically evaluate current literature on LLMs in dentistry. Data sources The search covered PubMed, Scopus, IEEE Xplore, and Google Scholar, with studies selected based on predefined criteria. Data were extracted to identify applications, evaluation metrics, prompting strategies, and deployment levels of LLMs in dental practice. Results From 4079 records, 17 studies met the inclusion criteria. ChatGPT was the predominant model, mainly used for post-operative patient queries. Likert scale was the most reported evaluation metric, and only two studies employed advanced prompting strategies. Most studies were at level 3 of deployment, indicating practical application but requiring refinement. Conclusion LLMs showed extensive applicability in dental specialties; however, reliance on ChatGPT necessitates diversified assessments across multiple LLMs. Standardizing reporting practices and employing advanced prompting techniques are crucial for transparency and reproducibility, necessitating continuous efforts to optimize LLM utility and address existing challenges.

Three biologically active new Schiff bases, 2-[(3-hydroxybenzylidene)amino]phenol 5, 2-[(4-hydroxybenzylidene)amino]phenol 6 and 4-[(2-hydroxyphenylimino)methyl]benzene-1,3-diol 7, were synthesized by the reaction of 2-aminophenol 1 with three different hydroxyl-benzaldehydes 2–4. They were characterized by spectroscopic analysis (IR, 1H NMR, EI-MS) along with elemental analyses. The products were biological screened out for antioxidant, lipoxygenase inhibition, antibacterial and urease inhibition activities. The compounds 5 and 6 showed potent while 7 showed moderate antioxidant activity. Compound 6 showed potent whereas 5 and 7 showed significant lipoxygenase inhibition activity. All the target compounds showed excellent activities against Staphylococcus intermedius, Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Salmonella typhi bacteria. All the compounds showed non-significant activity against urease enzyme.

A ligand L has been synthesized by the condensation of 4-chlorobenzaldehyde and 2-amino-5-chlorobenzophenone. The complexes 1–5 of Pb+2, Ni+2, Co+2, Cu+2 and Cd+2 with ligand were prepared. The newly synthesized ligand L and its complexes 1–5 were characterized on the basis of elemental analyses, molar conductance, 1H NMR, IR and MS spectral data. The ligand was also characterized by X-ray crystallography. By electronic spectra and magnetic moment data, the square planar geometry for complex 1 and the octahedral geometry for complexes 2–5 were proposed. The conductivity data suggests non-electrolytic nature of the complexes 1–5. The complexes have higher antibacterial activity than the parent ligand L.

Unsteady flows of a Newtonian fluid past an oscillating infinite isothermal vertical plate in a rotating frame are studied. Two closed forms of the velocity field are determined by means of Laplace transform method and by the technique of coupling of the homotopy perturbation method with the Laplace transform method. The equivalence of the obtained expressions for the velocity is provided. The friction coefficients are determined and, the influence of Ekman number on the velocity field is analyzed by graphical illustrations. It is obtained that, the faster frame rotations reduce the thickness of moving fluid layer.

The helical flows of couple-stress fluids in a straight circular cylinder are studied in the framework of the newly developed, fully determinate linear couple-stress theory. The fluid flow is generated by the helical motion of the cylinder with time-dependent velocity. Also, the couple-stress vector is given on the cylindrical surface and the nonslip condition is considered. Using the integral transform method, analytical solutions to the axial velocity, azimuthal velocity, nonsymmetric force-stress tensor, and couple-stress vector are obtained. The obtained solutions incorporate the characteristic material length scale, which is essential to understand the fluid behavior at microscales. If characteristic length of the couple-stress fluid is zero, the results to the classical fluid are recovered. The influence of the scale parameter on the fluid velocity, axial flow rate, force-stress tensor, and couple-stress vector is analyzed by numerical calculus and graphical illustrations. It is found that the small values of the scale parameter have a significant influence on the flow parameters.

Two new oxindole alkaloids isatinone A (1) and B (2) have been isolated from Isatis costata, along with the known trisindoline. Their structures have been assigned on the basis of spectroscopic techniques and chemical studies. Both new compounds showed significant antifungal activity.

Background: Inferile males have been shown to have lower levels of seminal plasma zinc which have been associated with reduced levels of zinc in their blood. Supplementation improve semen parameters by improving zinc level in blood. Objective: To fnd out whether zinc supplementation is effective in improving semen parameters in oligo­asthenozoospermic patients. Method: The study was carried out in the Infertility unit of the Dept of Obs & Gynae, BSMMU during the period of March 2011 to February 2012. Seventy five oligo-asthenozoospermic patients having no history of medical treatment were recruited for the study. The patients were divided into two groups by odd and even numbers. Odd numbers received tablet zinc 20 mg twice daily (Group A) and even numbers received placebo (Group B).Serum zinc level and seminal zinc level estimation were done by Graphite Furnace Atomic Absorption Spectropho­tometry and semen analysis was done according to WHO guidelines (1999). Data analysis was done using software SPSS (version 16) by applying ANOVA (PostHock) and Paired Student's 't' test. Results: Serum zinc level was low in oligo­zoospermic patients which showed significant improvement with zinc supplementation (A+ 197.83 mmol/1, P

Objective:To identify the non-obstetric causes and presentation of acute abdomen among pregnant women. Materials and methods:This was a cross sectional hospital-based study among 128 pregnant women by face to face interview using a semi-structured questionnaire. This study was conducted at the Gynecology & Obstetric Ward of 250 Bed General Hospital, Noakhali, Bangladesh, from January to August 2013. Data were analyzed by a software package used for statistical analysis (SPSS) version 11.5 (SPSS, Inc., Chicago, IL, USA).Mean age of participants was 25±4 years. Our findings showed that 81% were Muslim, 67% were lower middle income group, as well as 47% completed primary level of education. The results revealed that 28% had biliary ascariasis, 24% had peptic ulcer disease and 10% had lower urinary tract infection. We also found that 6% had acute pyelonephritis, 6% had acute gastroenteritis, 6% had acute cholecystitis, 6% had acute appendicitis, 2% had acute pancreatitis, 3% had choledocolithiasis, 2% had ovarian solid mass, 2% had twisted ovarian cyst, 4% had renal colic, and 1% had renal calculus. In non-obstetrical presentation of acute abdomen, the study found that 84% of respondents complained their pain lasting more than 24 hours. Besides, half of respondents felt pain in epigastrium and right hypochondrium. Cramping, prickling and aching type of pain were more, while 66% suffered from continuous pain. Our results also showed that 73% did not explain any aggravating factor and relieving factor, and the rest said food, fasting state and position change aggravated pain as well as relieved pain. Conclusion:The study concludes that precise diagnosis of the acute abdomen in pregnant women by continual updating of abdominal assessment knowledge, and clinical skills is necessary in the management of abdominal pain in obstetric settings.

In the title compound, [Cu(C12H18N2O2)]·0.25H2O, the coordination of the O,N,N′,O′-tetradentate ligand results in a cis-CuN2O2 square-planar geometry for the metal ion and the presence of two six-membered and one five-membered chelate rings. The complete complex molecule is close to planar (r.m.s. deviation = 0.047 Å). The uncoordinated water molecule (O-atom site symmetry 2) was modelled as half occupied. In the crystal, C—H...Ow and Ow—H...O (w = water) hydrogen bonds link the components into layers parallel to ab plane.

In the title compound, C20H13Cl2NO, the C=N bond adopts an E conformation. The chloro-substituted rings form a dihedral angle of 11.99 (9)° with each other and form dihedral angles of 74.95 (9) and 83.26 (10)° with the unsubstituted ring. In the crystal, molecules are connected into dimers by pairs of weak C—H...O hydrogen bonds and the dimers are arranged in columns parallel to the a axis.

In the title compound, C19H18N4O3, the pyrazole ring is oriented at dihedral angles of 41.12 (7) and 12.25 (10)°, respectively, with respect to the planes of the phenyl and benzene rings. Intramolecular N—H...O and O—H...O hydrogen bonds generate seven- and six-membered S(7) and S(6) ring motifs, respectively.

There are one-and-a-half independent molecules in the asymmetric unit of the title compound, C18H20N2O4. One molecule is centrosymmetric with the mid-point of the N—N bond located on a center of inversion. In the other, which lies on a general position, the benzene rings are aligned at 21.6 (1)°. Weak intermolecular C—H...O hydrogen bonding is present in the crystal strcture.

In the title molecule, C12H15NO5, the nitrophenoxy portion is approximately planar (r.m.s. deviation = 0.034 Å) and makes an angle of 84.8 (1)° with respect to the –CH2–C(=O)–O–C fragment. In the crystal, π–π stacking is observed between nearly parallel benzene rings of adjacent molecules, the centroid–centroid distance being 3.6806 (10) Å. Weak intermolecular C—H...O hydrogen bonding is present in the crystal structure.

In the title compound, C33H36O6, two naphthalene ring systems are connected through a methylene linkage [C—C—C = 114.9 (2)°]; the ring systems are aligned at an angle of 76.5 (1)°. Of the two –O–CH2–C(=O)–C(CH3)3 substituents, one adopts an extended conformation whereas the other is U-shaped. In the crystal, molecules are linked via weak C—H...O hydrogen bonding, forming supramolecular chains running along the c axis.

The molecule of the title compound, C19H14Cl2O2, has two benzene rings connected to a methylene C atom, and the rings are aligned at 66.3 (1)°. Intermolecular C—H...π and π–π stacking interactions are observed in the crystal structure, the centroid–centroid distances between parallel benzene rings being 3.7529 (12) and 3.6201 (12) Å, respectively.

The title compound, C18H16O7·H2O, is a flavonoid isolated from Dodonaea viscosa. The benzopyran ring system of the flavonoid is essentially planar [maximum deviation = 0.025 (2) Å] and inclined at 5.83 (2)° to the attached benzene ring. The water of hydration is involved in extensive hydrogen bonding, assembling the molecules into a supramolecular network via classical intermolecular O—H...O hydrogen bonding. The crystal structure is further stabilized by π–π stacking interactions [centroid–centroid distance between benzene rings = 3.564 (3) Å].

In the title molecule, C20H26O3, a clerodane diterpenoid isolated from Dodonaea viscosa, the trans-fused six-membered rings of the decaline system display chair conformations. The five-membered lactone ring adopts an envelope conformation and the five-membered furan ring is essentially planar with a maximum deviation of 0.0052 (12) Å.

In the title compound, C20H22O6, the mean planes through the benzene rings make a dihedral angle of 59.82 (7)° with each other. Weak intermolecular C—H...O interactions together with π–π stacking interactions [centroid–centroid distance = 3.830 (1) Å] between benzene rings are observed in the crystal packing.

In the title compound, C15H12N2O2, the seven-membered ring bearing the three methylene C atoms displays a puckered conformation, with the methylene C atoms deviating from the plane of the benzene ring by 0.05 (1), 0.98 (1) and 1.04 (1) Å. The phenanthroline unit is not planar; the dihedral angles between this benzene ring and the other pyridyl rings are 9.62 (4) and 9.31 (4)°. The crystal packing is stabilized by π–π interactions between two phenanthroline ring systems, forming a centrosymmetric dimer with a centroid–centroid distance of 3.656 (1) Å.

In the title compound, C13H12N4O6, the mean plane through the nitrobenzene forms a dihedral angle of 37.38 (15)° with the plane through the imidazole ring. The crystal packing is stabilized by weak intermolecular C—H...O and C—H...N interactions together with π–π stacking interactions between nitrobenzene rings [centroid–centroid distance = 3.788 (3) Å] and between imidazole rings [centroid–centroid distance = 3.590 (2) Å].

The molecule of the title compound, C13H12BrN3O4, is non-planar, as indicated in the dihedral angle of 59.5 (4)° formed between the least-squares planes through the imidazole and benzene rings. In the crystal, molecules are connected via C—H...O contacts, forming a supramolecular chain.

The title molecule, C21H26Br2O2, is a substituted diphenylmethane derivative whose angle at the methylene carbon is 115.0 (2)°.

The three independent molecules of the title compound, C15H14O4, have similar orientations of their aromatic rings, the dihedral angles between the rings being 57.0 (1), 58.1 (1) and 58.2 (1)°. In each molecule, the hydroxy group forms an intramolecular hydrogen bond to the carbonyl O atom, forming an S(10) ring motif.