Shear zones are important channels for the exhumation of lower crustal rocks. The Ambaji granulite of the Aravalli-Delhi mobile belt (ADMB) has been exhumed along several shear zones, and earlier studies have shown a two-stage exhumation process during a continuous compressional tectonic event, consisting of an initial phase of vertical flow that brought the granulites to the brittle-ductile transition zone and a successive phase during which the granulite underwent a lateral flow. In this contribution, we studied the microtectonics of granulites by analyzing the dynamic recrystallization behaviour of quartz, while the granulite was passing through the vertical flow regime to the horizontal flow regime. We show that the dynamic recrystallization process assists the flow pattern at different levels of exhumation. The vertical flow is dominated by grain boundary migration (GBM), registering high temperatures for recrystallization between 490 and 600°C and low flow stresses of 12-15 MPa. The horizontal flow at the brittle-ductile transition (BDT) is characterized by bulging (BLG) and subgrain rotation (SGR), which occurred at low temperatures of 390-490°C and high flow stresses of 18-26 MPa. Strain rates are between 1.20×10−12 and 7.26×10−14/s. For the ductile exhumation of the granulite, we suggest that at depths of ~22 km, the granulite exhumed in a vertical direction facilitated by GBM. Once the granulite reached the BDT, at ~16 km depth, the material flowed laterally assisted by BLG and SGR. Once an exhuming body reaches the BDT, the deformation mechanism changes to BLG-SGR, and the only direction in which the material can move further is in the horizontal plane.

The present study aims at developing and characterizing gum odina ‐ sodium alginate based microsphere as a carrier for capecitabine. Microspheres with varying concentration of polymers (gum odina and sodium alginate) were formulated using calcium chloride as a cross‐linker by ionotropic gelation technique. The formulated microspheres were optimized by entrapment efficiency, drug yield, particle size, swelling index, and in vitro drug release study. The optimized microsphere (F6) was characterized in terms of SEM, AFM, FTIR, XRD, degradation study, moisture content study, and antioxidant activity. The F6 was spherical in shape with a mean diameter of 568.33 ± 45.76 μm and drug entrapment efficiency of 45.91 ± 2.94%. In vitro dissolution study of optimized formulation exhibited negligible released in 0.1 N HCl (pH 1.2) and followed by 100% release in phosphate buffer (pH 7.4) within 24 h. In vitro cytotoxicity assay (MTT) of formulation F6 on HT29 human colon cancer cell line indicated inhibition of the proliferation of tumor cell over a longer period of time. The overall experiment indicated that capecitabine loaded natural polymers based formulated microsphere could be a promising approach for the prevention of colon cancer.

Colon cancer is the second most invasive cancer and fourth most common malignant neoplasm worldwide. Targeted oral colonic drug delivery systems have attracted considerable attention in the treatment of colon cancer due to their superior properties. However, the delivery of drugs safely and effectively to the target site of the colon tumor is a hindrance due to the complexity of the gastrointestinal structure. Herein, to achieve an effective delivery system specifically targeting the colon, we have taken concern by using natural polymer such as pullulan, signifying its flexibility and relevance in biomaterials science to design antineoplastic approaches. Here, we summarize the physicochemical properties, different pullulan derivatives and their biomedical application, several colon cancer‐related treatment, and pullulan and its derivatives‐based delivery systems towards colonic tissue.