We report the comparative aggregation behavior of three emerging inorganic 2D nanomaterials (NMs): MoS2, WS2, and h-BN in aquatic media. Their aqueous dispersions were subjected to aggregation under varying concentrations of monovalent (NaCl) and divalent (CaCl2) electrolytes. Moreover, Suwanee River Natural Organic Matter (SRNOM) has been used to analyze the effect of natural macromolecules on 2D NM aggregation. An increase in electrolyte concentration resulted in electrical double-layer compression of the negatively charged 2D NMs, thus displaying classical Derjaguin–Landau–Verwey–Overbeek (DLVO)-type interaction. The critical coagulation concentrations (CCC) have been estimated as 37, 60, and 19 mM NaCl and 3, 7.2, and 1.3 mM CaCl2 for MoS2, WS2, and h-BN, respectively. Theoretical predictions of CCC by modified DLVO theory have been found comparable to the experimental values when dimensionality of the materials is taken into account and a molecular modeling approach was used for calculating molecular level interaction energies between individual 2D NM nanosheets. Electrostatic repulsion has been found to govern colloidal stability of MoS2 and WS2 while the van der Waals attraction has been found to govern that of h-BN. SRNOM stabilizes the 2D NMs significantly possibly by electrosteric repulsion. The presence of SRNOM completely stabilized MoS2 and WS2 at both low and high ionic strengths. While h-BN still showed appreciable aggregation in the presence of SRNOM, the aggregation rates were decreased by 2.6- and 3.7-fold at low and high ionic strengths, respectively. Overall, h-BN nanosheets will have higher aggregation potential and thus limited mobility in the natural aquatic environment when compared to MoS2 and WS2. These results can also be used to mechanistically explain fate, transport, transformation, organismal uptake, and toxicity of inorganic 2D NMs in the natural ecosystems.

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Necrotizing sialometaplasia can make anyone very anxious about the lesion especially if they have habit of tobacco consumption. It requires a prompt diagnosis, counseling with assurance to patient and treatment.

Background. Diabetes mellitus is a metabolic disease which is seen increasing globally and is diagnosed and monitored on basis of invasive blood investigations. Salivary glands are affected in diabetes mellitus. The objective of this study was to assess ultrasonographic measurements of parotid glands and correlate with the glycosylated hemoglobin levels in type 2 diabetic mellitus and duration of type 2 diabetic mellitus and treatment regimens. Materials and Methods. This study was conducted on 50 subjects of type 2 diabetes mellitus and on 50 healthy controls. After HbA1C analysis of selected individuals, 100 individuals were grouped into group I (above 5.7) and group II (below 5.7). Ultrasonographic measurements (length (L), transverse dimension (TD), depth lateral to the mandible (DLM), and depth dorsal to the mandible (DDM)) of bilateral parotid glands were calculated. Statistical analysis was done using the chi-square test of significance and Spearman correlation coefficients. Results. On correlation with measurement of right (L, DLM, DDM) and left (TD, DLM, DDM) of parotid glands with duration of type 2 diabetes mellitus, we found a moderate positive relationship, whereas as for right (TD) and left (L), we found a low-positive relationship. Similarly, for right (L, TD, DLM, DDM) and left (TD, DDM) parotid glands with HbA1C, we found a low-positive relationship, whereas for left parotid gland (L, DLM) with HbA1C, we found a moderate positive relationship. The mean DLM of right and left parotids in the insulin group was found to be slightly more than that in the combined group which was statistically insignificant. Conclusion. Ultrasonographic measurements of parotid glands were found to be higher in study subjects as compared to control subjects, and they increased with increased HbA1C levels; also, there was no difference in treatment regimen. Ultrasonography could be a prospective diagnostic test for detection and monitoring of diabetes mellitus, and still further studies are required for this.

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