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4H-Chromene derivatives are promising anticancer compounds known to bind within the colchicine binding site of the tubulin protein. Among these, the 2-amino-4-phenyl-4H-benzo[h]chromene-3-carbonitrile-based 4H-chromenes scaffold is known to produce a significant impact on tubulin proteins. Other molecules with similar pharmacophores are also known for their colchicine binding site targeting abilities. However, tubulin is not a single protein; multiple isoforms have been reported, and some are comparatively more important under malignant conditions. Therefore, the research findings presented herein include a detailed understanding of the interaction pattern of the 2-amino-4-phenyl-4H-benzo[h]chromene-3-carbonitrile series for their colchicine binding ability against various tubulin isoforms proteins. We have established the current series anticancer potential and structural activity relationship. The series revealed promising anticancer potential, and MNC-1 was the best among all. However, a serious side effect of this scaffold is a major problem, as these derivatives indiscriminately bind to the tubulin of malignant and normal cells. However, the expression profile of tubulin isoforms was found to be different in normal and malignant cell types. Therefore, selective killing of the malignant cell seems possible by designing a 4H-chromenes derivative selective against particular tubulin isoforms. The insights provided herein clearly indicate the differences in the binding pattern of different 4H-chromenes derivatives against different tubulin isoforms. Therefore, with precise structural modification, these molecules' selective targeting against cancer cells seems quite possible. [ABSTRACT FROM AUTHOR]

On April 28 2021, an earthquake of MW 6.4 occurred near Sonitpur, Assam, India. The epicenter was 43 km away from Tezpur, Assam with a focal depth of 34 km. The National Center for Seismology (NCS), Delhi reported the maximum intensity of MMI-V whereas the United States Geological Survey (USGS) reported the maximum intensity of MMI-VII. Preliminary reports suggest a reverse slip component for the earthquake, which occurred close to the previously reported Kopili fault. This fault is the cause of two damaging earthquakes in the past i.e., 1869 Cachar earthquake and the 1943 earthquake. The April 28 2021, Sonitpur earthquake caused widespread liquefaction, building damage, and lateral spreading as far as 90 km from the epicenter. The present study reports preliminary damages and ground effects observed soon after the earthquake along with a comparative analysis with previously reported damages around the area during the historical earthquakes. The farthest reported liquefaction occurred during the earthquake was plotted with other case studies which were well in agreement with the previous literature. The possible reason for the extensive liquefaction and ground cracks is inferred to be due to site amplification within a sedimentary basin. Therefore, the occurrence of the 2021Sonitpur, Assam earthquake emphasizes the seismic hazard scenario for the Brahmaputra Basin and Bengal Basin, which further requires more detailed study in terms of paleoseismology, liquefaction hazard zonation and seismic hazard assessment. In addition, the damages to the buildings highlight the implementation of proper building codes considering the liquefaction hazard zonation map for the study area. [ABSTRACT FROM AUTHOR]

The Palaeozoic granites forming the Dalhousie pluton occur as an elongated body intruded into the core of an antiform in Salkhala metasedimentary rocks and are referred to herein as Dalhousie granites (DG). The studied mesoscopic structures, for example, well‐developed and randomly distributed megacrysts of K‐feldspar at the core part of massif, show undeformed porphyritic nature, whereas augen along with the mylonitic foliation and parallelly aligned feldspar megacrysts are dipping towards north‐north‐east (NNE) in the marginal part. The presence of aplite veins is evidence of final stage crystallization, where these rocks rapidly crystallized from siliceous residual fluids/solutions that escaped along fractures in the granites. Moreover, the granites show intrusive as well as thrusted contact with the Chamba metamorphics. The microscopic study from the marginal parts shows the dynamic recrystallization of quartz along with the fractures filled with secondary material oriented opposite to the top‐to‐the‐SW. Whereas euhedral quartz grains with undeformed grain boundaries, compositional zoning in plagioclase, and magmatic (perthite) texture of K‐feldspar are present in the core of Dalhousie pluton. In addition, a new whole‐rock geochemical dataset of DG is presented and investigated to elucidate the petrogenesis and tectonic environment. The geochemical data shows that DG (dominantly monzogranites) are formed from a pelitic source‐derived, (molar Al2O3/CaO + Na2O + K2O > 1.1) strongly peraluminous (S‐type) calc‐alkaline magma. This magma was generated by muscovite vapour absent dehydration melting. Harker bivariate plots indicate that fractional crystallization was a dominant process during the evolution of these granites. The tectonic discrimination diagrams suggest that DG were generated in syn‐collisional setting. Exceptionally high Pb in DG occurred due to primary melt generation at low‐temperature during partial melting (low‐degree melting) of the pelitic source rock. Trace and rare earth elements characteristics, such as positive anomaly of Zr show a notable amount of zircon as one of the accumulating phases. A pronounced negative Eu anomaly (EuN/Eu* = 0.04–0.66), along with high silica content and highly varied trace element ratios in these rocks, show that these are fairly evolved granites. [ABSTRACT FROM AUTHOR]