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Here were report on a laboratory study aiming to reproduce specificities of near-Earth Asteroid. We study how the elevated surface temperature, their surface roughness (rock or regolith), as well as observation geometry can affect the absorption features detected on asteroids. For that purpose, we selected a recent carbonaceous chondrite fall, the Mukundpura CM2 chondrite which fell in India in June 2017. Bidirectional reflectance spectroscopy was performed to analyze the effect of the geometrical configuration (incidence, emergence and azimuth angle) on the measurement. Our results show that reflectance spectra obtained under warm environment (NEA-like) tends to show shallower absorption bands compared to low-temperature conditions (MBA-like), but still detectable in our experiments under laboratory timescales. Irreversible alteration of the sample because of the warm environment (from room temperature to 250 °C) has been detected as an increase of the spectral slope and a decrease of the band depths (at 0.7 μm, 0.9 μm and 2.7 μm). Comparing the meteoritic chip and the powdered sample, we found that surface texture strongly affects the shape of the reflectance spectra of meteorites and thus of asteroids, where a dust-covered surface presents deeper absorption features. We found that all spectral parameters, such as the reflectance value, spectral slope and possible absorption bands are affected by the geometry of measurement. We observed the disappearance of the 0.7 μm absorption feature at phase angle larger than 120°, but the 3 μm band remains detectable on all measured spectra. • Reflectance spectroscopy of surfaces strongly depends on the viewing geometry. • Slope, absorption bands and photometry are affected by the geometry. • Warm meteorites present shallower absorption bands than in cold environment. • Irreversible alteration of the spectra are met at high temperature. • Dust-covered samples present deeper absorption bands than raw surface. [ABSTRACT FROM AUTHOR]

Multiple, small, cylindrical scroll coprolites having rounded and tapering ends and pertaining to a new ichnotaxon have been recovered from the Upper Triassic Tiki Formation of India. This is the first record of scroll coprolites from the Mesozoic. Based on cross‐sectional geometry, external surface textures, and internal morphology, these coprolites are subdivided into three morphotypes. The coprolites contain several kinds of undigested food material in the form of ganoid fish scales, teeth, lower jaw and skeletal remains of various osteichthyans, chondrichthyans, archosauriforms and indeterminate reptiles. These inclusions are embedded in the groundmass separated by thin mucosal layers. The groundmass contains abundant gas vesicles, and secondarily‐filled shrinkage cracks. EDS analysis shows that the overall composition of the coprolites reflects Ca, P, C and O, suggesting calcium phosphate mineralogy, though other elements such as Fe, Mn, Al, Si are present in lesser proportions. Based on their similarity with the scrolled faeces of extant euryhaline hammerhead sharks, it is deduced that these coprolites were produced by euryhaline hybodontid sharks. At least two hybodontid taxa, Lonchidion and Pristrisodus, show high prevalence in the Tiki vertebrate fauna, suggesting that these were the possible producers. As the coprolite inclusions contain remains of other aquatic animals, these carnivorous hybodonts constituted the dominant predators of the Tiki aquatic ecosystem. [ABSTRACT FROM AUTHOR]

The tropical moist deciduous forests of India are largely dominated by the dipterocarp tree Shorea robusta (also known as sal). Ectomycorrhizal (ECM) fungi form symbiotic association with sal trees and play an important role in the stability of the sal forests. A study was carried out to determine the occurrence and distribution of ECM fungi in tropical sal forests at the Shiwalik mountain range, north-west India. The genus Russula was the dominant fungi. In this paper the morphoanatomical details of mycorrhizal roots of S. robusta associated with three Russula species, namely, R. cremeoavallanea, R. romagnesiana and R. nigricans were investigated for the first time. The ECM colonised roots were distinguished by differences in the shape and colour of mycorrhizal system, surface texture, shape and size of cystidia, cell shape of mantle, as well as the differing chemical reactions. ECM roots of sal associated with R. cremeoavallanea were mostly greyish brown and have almost plectenchymatous outer mantle layers having subcylindrical to awl-shaped cystidia. Ectomycorrhizal roots of R. romagnesiana were reddish brown with silvery patches, and have purely plectenchymatous outer mantle layers having obpyriform to obclavate cystidia. Russula nigricans-associated ectomycorrhizal roots have greyish brown to black mycorrhizal system and have almost pseudoparenchymatous dark brown mantle with capitate cystidial elements. [ABSTRACT FROM AUTHOR]

• This study introduces image-based indices for assessing micro and macrotexture. • This study introduces the surface texture index to quantify pavement microtexture. • Aggregate shape, angularity and gradation indices were proposed for macrotexture. • Skid resistance of a constructed pavement, surface macrotexture index is proposed. • Skid resistance prediction was performed considering the image-based indicators. The objective of this study is to propose image-based indicators of microtexture and macrotexture for pavement surfaces that can predict the initial skid resistance. To achieve this objective, images of different types of aggregates that were collected from quarries were processed. Based on the outcome of the image processing, suitable indicators of shape, angularity, and surface texture of coarse aggregates were proposed. Skid resistance data were collected from pavements constructed with the aggregates used in the image processing, as well as with different surface course mixes commonly used in India, such as Bituminous Concrete (BC), Stone Matrix Asphalt (SMA), and Gap-Graded Rubberized Bituminous mix (GGRB). Through a detailed investigation of the image processing outcome and field data, this study introduces the Aggregate Surface Texture Index (STI) as a means of quantifying microtexture, which can be obtained by processing images of the aggregate using wavelet decomposition technique. Additionally, the study proposes Shape Index (SI) and Angularity Index (AI) as indicators for macrotexture, which can be obtained from the processing of digital images of aggregates. For determining the skid resistance of newly constructed pavements, the study suggests using the Surface Macrotexture Index (SMI), which can be obtained by processing digital images of the pavement surface. Furthermore, this study proposes statistical models for predicting the initial skid resistance of pavement based on these indicators. Overall, the proposed image-based indicators of microtexture and macrotexture have the potential to provide valuable insights for designing and maintaining safe and durable pavement surfaces. [ABSTRACT FROM AUTHOR]

• Adult midges preferred dark coloured sites for resting. • Sticky Resting Box (SRB) evaluation depicted males proportionately higher in lower SRB while females higher in upper SRB. • Culicoides preferred smooth SRB to rough SRB for resting. • SRB seems to be an effective tool for passive monitoring of resting adult vectors of Culicoides spp. Worldwide Culicoides biting midges transmit disease-causing agents that have significant economic impact on livestock industries. The aim of this study was to evaluate the sticky resting box traps to elucidate the resting behaviour of adult Culicoides in backyard cattle shed. Four different experiments were conducted over a six-month period based on types of resting box traps (material, colour, texture & height). During the study period 8870 individuals comprising 4046 (45.61%) males and 4824 (54.39%) females were collected. During the study period no significant preference was observed for the choice of resting box material (plywood & carton). For the colour experiment: adult Culicoides were retrieved from black box trap the most (21.15%) followed by blue (19.93%), red (17.84%), pink (14.06%), green (13.31%), yellow (7.21%) and the white (6.51%). Differential catch in the trap with surface texture (rough & smooth) was statistically significant (χ2 = 4.09, df = 1, P < 0.05). The highest proportion of males (n =987, 0.64) was recovered in the lower sticky resting box while the highest proportion of females (n =1318, 0.64) was collected in the upper sticky resting box during the study period. Sticky Resting Box (SRB) seems to be an effective tool for passive monitoring of resting adult vectors of Culicoides spp. prevalent in backyard sheds of West Bengal, India. [ABSTRACT FROM AUTHOR]

The scanning electron microscope (SEM) study of microtextures in quartz grains in India is still in infancy and restricted mostly to the placer or beach sediments. SEM study of micromorphology of quartz grains from Late Pleistocene-Holocene sediments in Uttarkashi district, Uttarakhand, has been taken up for understanding the depositional environment. In the Netal section the quartz grain micromorphological studies indicate basal part of a valley glacier environment or remnant glacial lake, as the quartz grains are angular with high silica deposition besides other imprints of glacial origin. In the Shiror section the sediment appears to be part of the glacial till. The present study provides a new approach to the much needed palaeoenvironmental evaluation of the Himalayan Quaternary sediments on a nanoscale. [ABSTRACT FROM AUTHOR]

Estimation of seismogenic potential through geological studies of faults is an important step in seismic hazard evaluation and mitigation. We investigated the Katrol Hill Fault (KHF), an E-W trending and south dipping high angle reverse fault in the seismically active Kachchh Basin at the western continental margin of India. While several faults in the eastern part of the basin are presently seismically active, the KHF is the only fault in the entire basin that is shown to have produced three Late Quaternary surface faulting events. We illustrate here an integrated geological approach using field mapping, microscopic analysis (petrography and quartz surface textures using SEM) and shallow geophysical surveys using GPR for determining the precise surface trace of the active KHF. We also determined the displacement and slip-rate for each surface faulting event. Based on the Late Quaternary surface faulting parameters deduced, we calculated the moment magnitude (Mw) of the events using well established empirical relationships. These calculations yielded Mw values consistently ≥ 6.5. Our study shows that the KHF is capable of producing high magnitude earthquakes. We infer that these surface faulting events may be of relatively shallow focus as higher magnitude earthquakes in recent times along other faults in the basin, except the 1819 Allahbund earthquake, did not produce surface rupture. We recommend a revision of seismic hazard risk and mitigation strategies of the region as a consequence of our findings. • Surface trace of active KHF is delineated by GPR, petrographic and quartz surface texture studies. • Mw values of three Late Quaternary surface rupturing events along Katrol Hill Fault are evaluated. • Consistent Mw values of ~6.5 suggest surface rupture hazard to engineering structures. [ABSTRACT FROM AUTHOR]

• AHP method is very effective to determine the weights of multiple parameters. • GIS capabilities were used in weighted overlay analysis of input parameters. • Integrated AHP and GIS approach found effective in assessing the land suitability. The aim of the present study was to assess the suitable areas for maize (Zea mays L) in semi-arid ecosystem of Mysuru district of Karnataka, Southern India using integrated Analytic Hierarchy Process (AHP) and Geographic Information System (GIS) approach. In the present study, the parameters of soil depth, length of growing period (LGP), soil surface texture, soil drainage, organic carbon (OC), soil pH, slope and elevation were used. AHP method was used to determine the weights of the parameters and scores of the sub-parameters in the study. The modeling capabilities of GIS were used in weighted overlay analysis of input parameters in assessment of land suitability for maize cultivation. The analysis indicates that about 29.9% (188439.4 ha) of the study area is highly suitable, 15.3% (96213.3 ha) is moderately suitable and 18.5% (116671.7 ha) is marginally suitable for maize cultivation. The study demonstrates that the integrated AHP and GIS approach found to be very effective to increase the accuracy in land suitability assessment. The gap analysis between the suitable areas derived from the study and actual mean maize growing area during 2015–16 to 2017–18, shows that about 23.2% (146370.4 ha) of highly suitable and 38.4% (242556.7 ha) of highly and moderately suitable areas together are available to expand the maize cultivation in the district. [ABSTRACT FROM AUTHOR]