This study delves into the realm of solving Einstein’s field equations within the framework of general relativity. In this paper, we present an exact solution derived through the vanishing complexity ...approach and offer a comparative analysis with the established embedding class one approach. This exploration sheds light on the efficacy and validity of these methods in generating solutions for Einstein’s field equations. Our study involves a comprehensive exploration of several key parameters, encompassing thermodynamic factors, causality conditions, stability evaluations, as well as analyses of the mass function. Based on our findings, it can be suggested that the vanishing complexity approach could serve as a viable alternative method to the embedding class one approach for the derivation of exact solutions of Einstein’s field equations.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study examines Einstein’s field equations in the context of general relativity, comparing five distinct methodologies: (a) vanishing complexity, (b) embedding class one or the Karmarkar ...condition, (c) conformally flat spacetime, (d) conformal killing symmetry, and (e) the Karmarkar scalar condition. The first four methods reveal a significant connection between two metric potentials, while the fifth method provides a coordinate-independent condition expressed in terms of structural scalars. The paper provides a comprehensive comparative analysis of a new exact solution derived by assuming a common metric function and solving the remaining metric functions through corresponding bridge equations to evaluate their effectiveness and validity. Critical parameters such as thermodynamic factors, causality conditions, stability, and mass function analysis are investigated.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The aim of the present paper is to study an anisotropic spherically symmetric core-envelope model of a super dense star in which core is equipped with linear equation of state, consistent with the ...quark matter while the envelope is considered to be of quadratic equation of state by adopting the philosophy of Takisa et al. (Pramana J Phys 92:40,
2019
). We demonstrate that all the physical parameters are realistic within the core as well as envelope of the stellar object and continuous at the junction. Our model is shown to be physically viable and substantiate with the strange stars SAX J1808.4-3658 and 4U1608-52. Further, We infer that if the mass of the star increases then central density results to higher values and core shrinks, which justifies the dominating effect of gravity for higher mass celestial objects.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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•Waste chicken eggshell derived CaO(cesp) based mixed metal oxides were prepared.•Transesterification of high free fatty acid containing non-edible oils were achieved using prepared ...catalysts.•CaO(cesp) based mixed metal oxides have shown better activity in comparison to neat CaO(cesp).•Best Conversions were achieved with ZnO–CaO(cesp).•Catalyst has shown good reusability up to 4 cycles without significant loss in its activity.
Solid base heterogeneous catalysts are one of the promising materials for the transesterification of vegetable oils because these catalysts are generally more reactive than solid acid catalysts which require very severe operating conditions. Calcium oxide has shown good catalytic activity due to its high basicity which is required for transesterification of triacylglycerides (TAGs). In the present study, the transesterification of non-edible, high free fatty acid containing Jatropha and Karanja oils was studied by using waste chicken egg shell derived calcium (i.e. CaO(cesp)) based mixed metal oxides (M-CaO; M=ZnO, MnO2, Fe2O3 and Al2O3) as heterogeneous catalyst. A comparison was also made on the catalytic performance of these prepared catalysts. The catalyst characterizations were done by XRD, SEM, TGA, FT-IR and BET techniques. The effectiveness of the catalysts was highly influenced by the calcination temperature. ZnO–CaO(cesp) catalyst was found to be the most efficient catalyst among all. The maximum conversion for the transesterification of Jatropha and Karanja oils were achieved using 5wt% catalyst, 65°C temperature and 12:1 methanol/oil ratio. The catalyst could be re-used effectively during four cycles. Use of the CaO(cesp) based mixed oxides made the process more environmental benign and economical. The biodiesel prepared has shown good fuel characteristics as per EN, ASTM and IS standards.
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GEOZS, IJS, IMTLJ, KISLJ, NUK, OILJ, SAZU, SBCE, UL, UM, UPCLJ, UPUK
Climate variability coupled with anthropogenic pressures is the most critical driver in the Himalayan region for forest ecosystem vulnerability.
Dactylorhiza hatagirea
(D.Don) Soo is an important yet ...highly threatened medicinal orchid from the Himalayan region. Poor regenerative power and growing demand have resulted in the steep decline of its natural habitats populations. The present study aims to identify the habitat suitability of
D
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hatagirea
in the Western Himalaya using the maximum entropy model (MaxEnt). The community climate system model (CCSM ver. 4) based on representative concentration pathways (RCPs) was used to determine suitable future areas. Sixteen least correlated (< 0.8) bioclimatic, topographical and geomorphic variables were used to construct the species climatic niche. The dominant contributing variables were elevation (34.85%) followed by precipitation of the coldest quarter (23.04%), soil type (8.77%), land use land cover (8.26%), mean annual temperature (5.51%), and temperature seasonality (5.11%). Compared to the present distribution, habitat suitability under future projection, i.e., RCP 4.5 and RCP 8.5 (2050 and 2070), was found to shift to higher elevation towards the northwest direction, while lower altitudes will invariably be less suitable. Further, as compared to the current distribution, the climatic niche space of the species is expected to expand in between11.41–22.13% in the near future. High habitats suitability areas are mainly concentrated in the forest range like Dharchula and Munsyari range, Pindar valley, Kedarnath Wildlife Sanctuary, West of Nanda Devi Biosphere Reserve, and Uttarkashi forest division. The present study delineated the fundamental niche baseline map of
D
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hatagirea
in the Western Himalayas and highlighted regions/areas where conservation and management strategies should be intensified in the next 50 years. In addition, as the species is commercially exploited illegally, the information gathered is essential for conservationists and planners who protect the species at the regional levels.
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Chromosomal aberrations are a hallmark of human cancers, with complex cytogenetic rearrangements leading to genetic changes permissive for cancer initiation and progression. Protection of Telomere 1 ...(POT1) is an essential component of the shelterin complex and functions to maintain chromosome stability by repressing the activation of aberrant DNA damage and repair responses at telomeres. Sporadic and familial mutations in the oligosaccharide-oligonucleotide (OB) folds of POT1 have been identified in many human cancers, but the mechanism underlying how hPOT1 mutations initiate tumorigenesis has remained unclear. Here we show that the human POT1's OB-folds are essential for the protection of newly replicated telomeres. Oncogenic mutations in hPOT1 OB-fold fail to bind to single-stranded telomeric DNA, eliciting a DNA damage response at telomeres that promote inappropriate chromosome fusions via the mutagenic alternative non-homologous end joining (A-NHEJ) pathway. hPOT1 mutations also result in telomere elongation and the formation of transplantable hematopoietic malignancies. Strikingly, conditional deletion of both mPot1a and p53 in mouse mammary epithelium resulted in development of highly invasive breast carcinomas and the formation of whole chromosomes containing massive arrays of telomeric fusions indicative of multiple breakage-fusion-bridge cycles. Our results reveal that hPOT1 OB-folds are required to protect and prevent newly replicated telomeres from engaging in A-NHEJ mediated fusions that would otherwise promote genome instability to fuel tumorigenesis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Soil conservation and C sequestration are critical issues in rainfed farming of the Indian Himalayas. This study, conducted from 2003 through 2009 on a sandy clay loam soil (Typic Haplaquept) near ...Almora, India, evaluated the effect of seasonal tillage alterations (year-round conventional tillage CT–CT, year-round no tillage NT–NT, CT in the Rabi winter season and NT in the Kharif summer/rainy season (CT–NT) and the reverse NT–CT of the latter treatment) on soil organic carbon (SOC) retention, soil aggregation, aggregate-associated C concentrations and particulate organic matter-carbon (POM–C) in the 0- to 15-cm soil layer. Results indicate that the plots under NT–NT, NT–CT, and CT–NT had nearly 16, 12, and 10% higher total SOC content compared with CT-CT (∼12 g kg−1 soil) in the 0-to 5-cm soil layer. However, tillage had no impact on total SOC content in the subsurface (5- to 15-cm) soil layer. Although the labile pools of SOC were positively affected by conservation tillage practices (CT–NT, NT–NT, and NT–CT), the less labile pool was only influenced by the continuous NT and NT–CT in the 0- to 5-cm depth. Plots under NT–NT and NT–CT had about 27 and 19% higher labile SOC pool than CT–CT plots (5.65 g C kg−1 soil), and NT–NT and NT–CT plots had about 14 and 11% higher less labile SOC pool than CT–CT plots (2.61 g C kg−1 soil) in that soil layer. Plots under NT–NT and one seasonal tillage (NT–CT and CT–NT) also had higher macroaggregates and macroaggregate-associated SOC after 6 yr of study than CT–CT plots. Greater proportion of microaggregates within macroaggregates in the plots under NT–NT compared with CT–CT was also observed in the surface layer only. The NT–CT plots had similar effects on all studied soil properties to CT–NT plots, apart from the mean weight diameter (MWD) and labile SOC pool in the 0- to 5-cm soil layer were higher under former plots than the latter. Plots under NT–NT had about 10% higher coarse (250–2000 μm) intra-aggregate particulate organic matter-C (iPOM–C) within >2000 μm sand free aggregates in the 0- to 5-cm soil layer compared with CT–CT plots. The fine (53–250 μm) iPOM–C within the 250- to 2000-μm aggregates was also higher in the continuous NT plots compared with CT within both >2000 and 250 to 2000 μm sand free aggregate size classes in that soil layer. Thus, the adoption of continuous NT is the best management option for improvement of soil C under a rainfed lentil Lens esculentus (L.)–finger millet Eleusine coracona (L.) Gaertn. cropping system of the Indian Himalayas, as the management practice has the potential to improve productivity and soil aggregation with greater accumulation of POM-C, and SOC stabilization apart from other known benefits like weed control, less cultivation cost, and higher profits.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In this paper, we prove some fixed point theorems for Lipschitz type mappings in the setting of metric spaces. Our results open up the unexplored area of fixed points of Lipschitz type mappings for ...investigation.
This study examines the energy requirement and energy input–output relationship of colocasia-based cropping systems viz., Colocasia–onion–frenchbean, colocasia–gardenpea–frenchbean, ...colocasia–wheat–okra, colocasia–radish–potato, colocasia–cabbage–frenchbean, colocasia–coriander–cauliflower–frenchbean, colocasia–corinder–tomato and rice–wheat in the Indian Himalayas. Results revealed that potato consumed the highest total input energy (25084 MJ/ha) and the least was in coriander (5108 MJ/ha). System productivity in terms of colocasia equivalent yield was highest with colocasia–onion–frenchbean system (52.38 t/ha). Mineral fertilizers (50–62%), seed (8–26%) and irrigation water (11–17%) consumed the bulk of the input energy for all cropping systems. The total input energy was highest under colocasia–radish–potato (59919 MJ/ha) and the lowest in rice–wheat (38244 MJ/ha). Colocasia–onion–frenchbean, with the highest system productivity, produced the highest energy productivity (1.203 kg/MJ). Colocasia–coriander–tomato, with the highest system biomass, produced higher energy ratio (30.4), human energy profitability (2813.4) and energy profitability (29.43). Colocasia–wheat–okra (1362928 MJ/ha) recorded the highest total energy output. Human energy profitability was highest under colocasia–coriander–tomato (2813.4) indicating that it was the most labor energy efficient cropping system. Hence, the colocasia–corinder–tomato and colocasia–onion–frenchbean cropping systems are more suitable in the Indian Himalayas for their higher energy use efficiency and energy productivity, respectively, and are advised for wide adoption.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Paris polyphylla J.E. Smith is extensively used in traditional systems of Indian and Chinese medicines mainly for its anticancerous property. The national and international demand for P. polyphylla ...is constantly increasing and most of the supplies come from wild. Illegal and unscientific exploitation coupled with habitat destruction decreases the natural population of the herb, as a consequence this species comes under vulnerable category. Restoration and conservation of the natural population of this potential herb is prerequisites. This article aims to provide an overview on chemical and biological prospective of P. polyphylla. Secondary metabolites such as daucosterol, polyphyllin D, β -ecdysterone, Paris saponins I, II, V, VI, VII, H, dioscin, oligosaccharides, heptasaccharide, octasaccharide, trigofoenoside A, protogracillin, Paris yunnanosides G-J, padelaoside B, pinnatasterone, formosanin C and 20-hydroxyecdyson saponins have been isolated from P. polyphylla. Several biological activities such as anticancerous, antitumor, cytotoxic, anthelmintic, antimicrobial, antiangiogenic, immunostimulating, contractile and hemostatic have also been reported. Consequently, this review will be helpful to the researcher and scientist for further research.
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