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Differential scanning calorimetry (DSC) technique is used to study the solid reactions in the 2024 Al–Cu–Mg and 2014 Al–Cu–Mg–Si alloys of solutionised-water quenched, naturally aged, artificially under-, peak-, over-aged states at four different heating rates ( v h ) of 5 °C min −1 , 10 °C min −1 , 15 °C min −1 and 20 °C min −1 . All the exothermic and endothermic peaks in the DSC curves have been identified and discussed. The noticeable differences observed in the DSC curves of the 2024 and 2014 alloys have been explained which are attributed to the variations of the Cu, Mg and Si solute contents. DSC curves showed at different heating rates that all the peaks (except a few) have shifted to higher temperature with increasing heating rates ( v h ). The peak temperatures ( T p ) and the heat evolved and absorbed (∆ H ) during the precipitation and dissolution reactions have been determined with the help of in-built software available with the DSC unit. Attempts have been made to explain the solid-state reactions sequences in these alloys with the help of XRD and TEM micrographs.

The sperm quality, freezability, and fertility of crossbred bulls exhibit significant unpredictability, which consequently impacts the breeding program. The present study documents the supplementation of humanin, a mitochondria-derived peptide, on crossbred bull’s sperm quality, freezability, antioxidant status and in-vitro fertility. For this objective a total of 24 ejaculates, 8 from each of the three Vrindavani crossbred bulls, were selected based on sperm progressive motility (≥ 70%) and concentration (≥ 500 million). The selected fresh semen samples were divided into four aliquots and diluted with Tris-Fructose-Egg-Yolk-Glycerol (TFEGY) extender supplemented with various concentrations of humanin peptide; control (Group-1) without supplementation; Group II with 2.5 µM; Group III supplemented with 5 µM and Group IV supplemented with 7.5 µM. Semen quality parameters, sperm kinematics, sperm plasma membrane integrity, mitochondrial membrane potential, sperm cryo-capacitation status, ejaculate freezability rate, antioxidant status and in-vitro fertility assays were done. At the pre-freeze stage, there was no significant effect on the percentage of individual progressive motility in any group. Supplementation with 5 µM humanin resulted in an 87.5% ejaculate recovery rate after cryopreservation. At the post-thaw stage, sperm quality parameters, sperm kinematics, sperm plasma membrane integrity, mitochondrial membrane potential, sperm cryo-capacitation status, antioxidant status and in-vitro fertility were significantly improved in Group III (5 µM humanin supplementation). In conclusion, our results demonstrate that humanin supplementation in crossbred bull semen enhances semen freezability and post-thaw ejaculate recovery rate.

Chiral superconductors are novel topological materials with finite angular momentum Cooper pairs circulating around a unique chiral axis, thereby spontaneously breaking time-reversal symmetry. They are rather scarce and usually feature triplet pairing: a canonical example is the chiral p -wave state realized in the A -phase of superfluid He 3 . Chiral triplet superconductors are, however, topologically fragile with the corresponding gapless boundary modes only weakly protected against symmetry-preserving perturbations in contrast to their singlet counterparts. Using muon spin relaxation measurements, here we report that the weakly correlated pnictide compound LaPt 3 P has the two key features of a chiral superconductor: spontaneous magnetic fields inside the superconducting state indicating broken time-reversal symmetry and low temperature linear behaviour in the superfluid density indicating line nodes in the order parameter. Using symmetry analysis, first principles band structure calculation and mean-field theory, we unambiguously establish that the superconducting ground state of LaPt 3 P is a chiral d -wave singlet. Chiral superconductors are very rare topological materials. Here, the authors report spontaneous magnetic fields inside the superconducting state and low temperature linear behavior in the superfluid density in LaPt 3 P, suggesting a chiral d -wave singlet superconducting state.

In this study, the effect of irradiation temperature on microstructural evolution of Indian RPV steel is reported. This study, by virtue of helium ion irradiation at 77, 300 and 573 K, could bring out the effect of the irradiation induced defects on microstructural and mechanical property changes at different stages of their existence starting from the state of cascade damage till the point of their free migration. Irradiation experiments were performed with varying ion energies to achieve nearly uniform irradiation damage of 0.05, 0.2 and 3 dpa in a ~ 300 nm wide region. Irradiated samples were characterized using GIXRD, PAS, TEM and nanoindentation. Unirradiated samples showed predominant presence of a combination of di- and tri-vacancy type of defects. Most of the dislocations present in unirradiated samples were screw dislocations, while mixed type was noticed upon irradiation irrespective of the irradiation temperature. PAS study showed formation of distinct defect types at different irradiation temperatures. TEM study confirmed formation of dislocation loops and defect clusters on irradiation. Higher irradiation temperatures resulted in the extension of the width of the damage region owing to increased migration of defects.

One of the challenging task in agriculture is mapping of crops using satellite images as spectral properties of the crops looks similar to each other, and there are many complexities which are there in the field such as small land holdings, heterogeneous and often distinct field patterns. In past, mapping with high resolution satellite images was not possible due to the non-availability of data and even they were costlier. However, with the free availability of PlanetScope dataset having 8 spectral bands, with daily revisit cycle and resolution of 3m, it is now possible to carry out mapping and monitoring of agriculture crops. The objective of the study is to classify major crops of rabi (December-April) season using single date PlanetScope imagery in the Haridwar district, Uttarakhand, India. Classification of crops has been carried out using an ensemble based machine learning algorithms within Google earth engine. Off late, Google Earth Engine (GEE), a cloud based platform has attracted the attention of remote sensing analyst since it expediates the classification yielding good results of high quality. In this study, Random Forest (RF) and Gradient Tree Boosting algorithm (GTB) have been used after performing hyper-parameter tuning and results shows that overall accuracy obtained by RF and GTB are 88% and 86.5% respectively. According to the results, both classifier performed well but RF achieved 1.5% high accuracy over GTB. Analysis of the results show that highest accuracy was attained by agriculture class (wheat) while other crops class exhibited lower accuracy. In this study, RF was found to be more competent as compared to GTB in classifying the crops and PlanetScope 8 band dataset has also proved its potential in classifying crops in heterogeneous fields.

NRC publication: Yes

Due to a change in the landscape, the climate of Uttarakhand state is changing rapidly, impacting the weather, further affecting human beings and vegetation. Nowadays, remote sensing is a favorable tool for monitoring the vegetation condition using NDVI and EVI. Studying the relationship between vegetation and climate more extensively, it is necessary to better understand the anomaly of ecosystems with climate change. This study is carried out to evaluate the vegetation cover dynamics by establishing the association between climate parameters and vegetation indices over the rain-fed districts (Nainital, Bageshwar, Champawat, Dehradun) of Uttarakhand for the period of 20 years. In this study, Google Earth Engine (GEE) is used to extract the MODIS NDVI and EVI at 250 m spatial resolution & 16-day temporal resolution data. The climate parameters for the rain-fed district (study area) are extracted from Indian Meteorological Department (IMD) Pun website for the period from 2000 to 2020. According to the annual vegetation dynamics, the peak attained by both indices is during the monsoon season, and hence they both show identical patterns to each other. Linear Regression Analysis results show a strong impact of climate on vegetation. Both indices shows a positive correlation with climate parameters where minimum temperature and rainfall are strongly correlated with EVI. Thus, the study reveals that EVI is proven to be more appropriate indices for monitoring vegetation cover as compared to NDVI for the study area.

BACKGROUND: Stylomastoid foramen is the terminal part of facial canal and is the exit gateway for facial nerve from skull base. We hypothesized that anatomical variations of this foramen could be a risk factor for the injury of facial nerve resulting in unilateral facial nerve paralysis or Bell’s palsy. Hence the present study was conducted to study the variations in size and shape of stylomastoid foramen in dry adult human skulls. MATERIALS AND METHODS: The study was conducted on 37 dry adult human skulls of unknown age and sex. High resolution images of the skulls under study were processed by ImageJ software and observations were undertaken. RESULTS: Total eight variations of stylomastoid foramen were observed in terms of shape. The common variants were round, oval and square (present in 83.79% skulls on right side and 81.07% skulls on left side), whereas the rare variants were triangular, rectangular, serrated, bean-shaped and irregular. It was noted that stylomastoid foramen were associated with extensions (45.95% skulls) and also adjacent foramen (18.92% skulls). Exclusively unilateral observations included bifurcation of foramen (16.22% skulls), foramen situated deep inside skull groove (5.41% skulls) and foramen interrupted by bony spur (2.7% skulls). No significant differences were observed between the mean diameters (antero-posterior and transverse) of the stylomastoid foramen. CONCLUSIONS: The unilateral variations along with rare variations in terms of shape such as serrated, bean-shaped and irregular foramen (which were also unilateral findings) could be potential risk factors towards injury of facial nerve at the point of exit from skull base leading to Bell’s palsy.

Corrosion of steel rebars and susceptibility of reinforcement steel to chloride ion attacks are the two major problems for the construction industries and thereby a huge amount of money is spent to repair it. Epoxy coating on the steel rebars can be one cost-effective solution to alleviate the detrimental effects of corrosion in concrete structures. In the present research, plain and epoxy coated rebar (ECR) samples were chosen to study the correlation between microstructure, hardness and corrosion performance. The microstructures of the investigated thermomechanically treated (TMT) rebars primarily reveal tempered martensitic rings at the outer surface followed by a narrow bainitic transition zone in between along with a ferrite-pearlite microstructure at the inner core. The corrosion resistance of plain and epoxy-coated rebars in naturally aerated 3.5% NaCl and 1% HCl solutions were studied using gravimetric test, open circuit potential (OCP) test, and linear polarization monitoring techniques. It has been witnessed that the corrosion current (i corr ) has been shifted towards lower values and polarization resistance (R p ) values are higher for ECR samples which is a clear indication of higher corrosion resistance of the ECRs than the plain rebars. Energy dispersive spectroscopy (EDS) analysis reveals the presence of iron hydroxides and iron oxides. However, x-Ray diffraction (XRD) analysis indicates the existence of various types of oxides, hydroxides, and oxy-hydroxides like iron chloride hydroxide [Fe 2 (OH) 3 Cl], goethite ( α -FeO(OH)), lepidocrocite ( γ -FeO(OH)), magnetite (Fe 3 O 4 ) and bernalite [Fe(OH) 3 (H 2 O) 0.25 ] in the epoxy coated rebar samples whereas, plain rebars indicate the presence of goethite ( α -FeO(OH)), maghemite ( γ -Fe 2 O 3 ), magnetite (Fe 3 O 4 ), hydrogoethite (Fe 2 O 3 .H 2 O), lepidocrocite ( γ -FeO(OH)) and iron oxide (Fe 21.34 O 32 ). All the experimental results confirm that ECR samples are more corrosion resistant under both acidic and saline environments.

The present study investigates the effect of annealing time and temperature on the microstructural restoration (by recovery and recrystallization), texture evolution and tensile properties of a dual-phase TWIP steel. The samples, which were initially hot rolled-air cooled followed by being in solution treated condition, subsequent 50 pct cold rolled condition and different annealing conditions (temperatures ranging from 500 °C to 1000 °C for 5 minutes to 2 hours), were subjected to microstructural characterization using optical and transmission electron microscopy, electron backscatter diffraction analysis, tensile testing and fractographic study. The deformation-induced ferrite (DIF) transformation due to cold deformation, the evolution of the grain structure and texture in both austenite and ferrite, and the change in the DIF fraction (accompanying the recrystallization annealing treatment) are critically analyzed. The optimum combination of strength and ductility is achieved in the partially recrystallized samples annealed at 700 °C for 30 minutes (UTS: 859 MPa, total elongation: 37 pct) and 900 °C for 30 minutes (UTS: 708 MPa, total elongation: 63 pct).The effects of DIF on the evolution of microstructure and texture during annealing and the final properties are discussed.