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In Situ Rainwater Conservation Through Half-Moon Terraces for Sustaining C. registanense in the Indian Thar Desert
No full textCynanchum registanense Jayanthi is a rare threatened species of the arid region which needs conservation efforts. We report here its diversity in nature and efficacy of traditional rainwater conservation structure, i.e., half-moon terrace (HMT) in accelerating plant regeneration and population buildup as well as in situ conservation. Two biotypes of C. registanense found in nature are (i) common on rocky crevices having crisped margin leaves with light yellow flowers, and (ii) growing on sand deposition having leaf margin entire and dark yellow flowers. Ecologically, it is a subdominant species with relative importance values ranging from 8.71 to 49. Monitoring plant population and growth parameters for 3 years showed that the HMT conserving sufficient rainwater quantities successfully regenerated plants of C. registanense. Box-whisker plots revealed relatively high annual variability of the plant populations and high median values in four quadrats situated closer to the embankment of HMT as compared to those located away from the embankment. Comparing mean plant populations between adjacent pairs of quadrats using a t-test revealed that C. registanense regenerating within 5 m of HMT embankment flourished better than those growing farther away. Plant population showed a moderately positive linear relationship (R2 = 0.30), significant at p > 0.10. It was further revealed that a minimum of 27 mm rainfall spread over 6-day period is essential for conserving C. registanense. Overall, findings of this study proved existence of variability in habitat-specific C. registanense in arid region of western Rajasthan, which could be conserved in situ and enhanced in its density by a traditional rainwater conservation method
Evaluating bioeconomic potential of Phyllostachys mannii Gamble, a monopodial bamboo and Chimonocalamus griffithianus (Munro) Hsueh & T.P. Yi, a sympodial bamboo from north-eastern India
No full textThe bioeconomic potential of monopodial and sympodial bamboos is not well understood. Therefore, Net primary productivity (NPP), total biomass, carbon (C) stock, soil organic carbon (SOC), CO2 sequestration, and bioenergy potential were studied in a sympodial Chimonocalamus griffithianus and a monopodial Phyllostachys mannii bamboo in Meghalaya, north-eastern India. P. mannii stand with mean culm density 16,877 ha-1, height 14.8 m and diameter 4.4 cm, accumulated 107.56 Mg ha-1 biomass with a total NPP of 18.83 t ha-1yr-1. It stored 50.67 Mg C ha-1 in biomass, 77.28 Mg C ha-1 in soil, and had sequestration potential of 469.58 t CO2 ha-1. C. griffithianus stand with mean clump density 1065 ha-1, mean culm density 52,185 ha-1, height 7.19 m and diameter 3.04 cm, accumulated 67.08 Mg ha-1 biomass with a total NPP of 15.30 t ha-1 yr-1. It stored 31.30 Mg C ha-1 in biomass, 83.25 Mg C ha-1 in soil, and had sequestration potential of 420.40 t CO2 ha-1. Matured culms (>2–3 years old) of P. manni and C. griffithianus produced 143.08–166.65 MW h and 87.13–101.48 MW h of energy per ha, respectively. Although landuse history and site characteristics of the two stands were not 10037; identical, significantly greater (p<0.05) standing biomass, NPP, growth rate, carbon sequestration potential, and energy values of P. mannii than C. griffithianus makes the monopodial bamboo a better choice for energy plantation and climate change mitigation tool than the sympodial
Development of genome-wide microsatellites from Primula denticulata and their utility in different species of the genus
No full textThe genus Primula (Primulaceae) harbours habitat-sensitive species. It is a valuable tool for monitoring and assessing the overall state of the ecosystem as it can serve as a reliable indicator of ecological health. Primula denticulata Sm. is one of the most prevalent Primrose species found in the Indian Himalayan region with a wide extent of distribution from 1500 m to 3500 m altitude. Considering the ecological importance of Primulas, it is imperative to develop microsatellite markers to study genetic variability which can offer valuable insights into the adaptive strategies of the plants in response to changing environmental conditions. In this study, we sequenced the P. denticulata genome by utilizing Illumina paired-end sequencing technology at ∼15X coverage. 27,196 sequences harbouring 31,584 microsatellite loci were identified. 100 primer pairs were synthesized and tested for amplification. Impressively, 84 of these primers exhibited robust amplification, and 64 of these displayed polymorphism. Primer pairs from trinucleotide motifs were identified as more polymorphic. To assess the broader applicability of these primers, we also tested cross-species transferability on 14 different Primula species representing different sections of the genus that were collected from different parts of Himalaya. Notably, one SSR locus, Next Generation Sequencing Primula_5 (NGSPr_5) was able to produce bands in all the species showing 100 % transferability. Primula atrodentata showed a maximum (88.23 %) while P. glabra exhibited minimum (19.60 %) cross-transferability. The UPGMA dendrogram clustered different sections of sub-genus Aleuritia, and species from subgenera Sphondylia and Auganthus separately into two major groups. The groupings are in accordance with the known relationship between the different species from the genus
TDP1 phosphorylation by CDK1 in mitosis promotes MUS81-dependent repair of trapped Top1-DNA covalent complexes
No full textTopoisomerase 1 (Top1) controls DNA topology, relieves DNA supercoiling during replication and transcription, and is critical for mitotic progression to the G1 phase. Tyrosyl-DNA phosphodiesterase 1 (TDP1) mediates the removal of trapped Top1-DNA covalent complexes (Top1cc). Here, we identify CDK1-dependent phosphorylation of TDP1 at residue S61 during mitosis. A TDP1 variant defective for S61 phosphorylation (TDP1-S61A) is trapped on the mitotic chromosomes, triggering DNA damage and mitotic defects. Moreover, we show that Top1cc repair in mitosis occurs via a MUS81-dependent DNA repair mechanism. Replication stress induced by camptothecin or aphidicolin leads to TDP1-S61A enrichment at common fragile sites, which over-stimulates MUS81-dependent chromatid breaks, anaphase bridges, and micronuclei, ultimately culminating in the formation of 53BP1 nuclear bodies during G1 phase. Our findings provide new insights into the cell cycle-dependent regulation of TDP1 dynamics for the repair of trapped Top1-DNA covalent complexes during mitosis that prevents genomic instability following replication stress
Roadmap on perovskite light-emitting diodes
No full textIn recent years, the field of metal-halide perovskite emitters has rapidly emerged as a new community in solid-state lighting. Their exceptional optoelectronic properties have contributed to the rapid rise in external quantum efficiencies (EQEs) in perovskite light-emitting diodes (PeLEDs) from <1% (in 2014) to over 30% (in 2023) across a wide range of wavelengths. However, several challenges still hinder their commercialization, including the relatively low EQEs of blue/white devices, limited EQEs in large-area devices, poor device stability, as well as the toxicity of the easily accessible lead components and the solvents used in the synthesis and processing of PeLEDs. This roadmap addresses the current and future challenges in PeLEDs across fundamental and applied research areas, by sharing the community’s perspectives. This work will provide the field with practical guidelines to advance PeLED development and facilitate more rapid commercialization
On the role of volcanic plume heights in excitation of free oscillations of the solid Earth and atmosphere: Case study
No full textVolcanic eruptions are potential sources for generating the Earth’s free oscillations at spheroidal modes of 0S 29 and 0S 37 through acoustic resonant coupling between the Earth and its atmosphere. Then, does every volcano produce Earth’s free oscillations? We answer this question by analyzing eight large volcanic eruption events, (i) 15 January 2022 Hunga Tonga-Hunga Ha apai (HTHH), (ii) 13–14 January 2022, HTHH, (iii) 13 August 2021 Fukutoku-Okanoba, (iv) 22 April 2015 Calbuco, (v) 13 February 2014 Kelud, (vi) 4 November 2010 Merapi, (vii) 15 June 1991 Mt Pinatubo, and (viii) 4 April 1982 El Chichon. Our analysis revealed that the 15 January HTHH, Mt. Pinatubo, and El Chichon eruptions excited the Earth’s free oscillations globally at spheroidal modes of 0S 29 and/or 0S 37 but no such modes were excited during other eruptions. However, harmonic oscillations in the ionosphere were seen during all recent eruption events. We demonstrate that stronger eruptions excite stronger atmospheric modes as the plume arrives at higher atmospheric heights which enable efficient ground-atmosphere acoustic resonant coupling for the excitation of spheroidal modes. Further, we hypothesize that relatively weaker eruptions/lower plume height perhaps caused weakly confined atmospheric modes thus failure of excitation of the spheroidal modes. A quantitative analysis of source efficiency versus source heights provides more insights into our hypothesis
Lithospheric magnetic anomaly map of Indian subcontinent (LAMI-1) from Swarm satellite data
No full textA preliminary lithospheric magnetic anomaly map of the Indian subcontinent (LAMI-1) was generated utilising seven years (April 2014–December 2020) of data recorded by the Swarm satellite constellation. To obtain a high-resolution lithospheric anomaly map, the fields originating from sources other than lithospheric sources are eliminated sequentially. The external field component is minimised by selecting the days of low geomagnetic activity (Kp < 2 and –20 < Dst < 20) within night-time hours. The main and the remaining external field sources are removed using data from CHAOS model. The model of residual data is achieved directly through the damped least square inversion technique by expanding the Legendre polynomial of order n = 6–50. The resulting satellite-derived lithospheric magnetic anomaly mostly reflects intermediate to long wavelength deep geological phenomena, with diverse tectonic provinces exhibiting discrete magnetic fingerprints/impressions with amplitudes ranging from high to low. Various tectonic blocks of the Indian subcontinent show distinct signature in the derived lithospheric anomaly map. The Himalayas and the Deccan Volcanic Province are associated with low magnetic signatures. The Central Indian Tectonic Zone and the Arakan Yoma Fold belt appear to have positive magnetisation. The division of Dhawar Craton into Western and Eastern Dharwar by Chitradurga Boundary shear is clearly evident in the anomaly map. A possible track of the Reunion hotspot is depicted as a north–south oriented high within the Marwar block. The comparison between the vertical (Z) component of LAMI-1 with the vertical component of MAGSAT data and MF7 lithospheric model from Champ satellite data indicates the LAMI-1 model shows far less noise and sharper anomalies with tectonic blocks better resolved compared to the other models
Optimal site selection for the geomagnetic measurements at Hanle Observatory in Ladakh, India: Insights from magnetic campaign survey
No full textThe Himalayas are a region of geomagnetic importance, as they impact the geomagnetic field of Earth and space weather, as it is one of the largest mountain belts in the world. Due to its huge mass, it may influence the dynamics of the Earth’s core, the primary source of the geomagnetic field. In Indian longitudes, the mean location of the solar quiet (Sq) focus lies in latitudes closer to the Hanle region. Therefore, monitoring the magnetic field in the Hanle region is important. Ideally, a zero magnetic gradient or low magnetic gradient of the order of a few nT/m or less is preferred; this low gradient helps reduce the effects of local magnetic variations. Hence, to establish a continuous geomagnetic observation setup, a magnetic survey was conducted at Hanle, Ladakh, to identify the location of the low magnetic gradient. From the magnetic survey, the eastern part of the selected hillock was identified that has the least magnetic gradient. After checking other logistics, the chosen site is suitable for setting magnetic field observations. The proposed magnetic observatory at Hanle will be useful for studies related to unusual space weather phenomena, such as the citing of Auroras (of 22–23 April 2023 and 10–11 May 2024) in the Ladakh region, geomagnetic field monitoring in low-mid transitional regions, or magnetic exploration
Modelling HIV-1 control and remission
No full textRemarkable advances are being made in developing interventions for eliciting long-term remission of HIV-1 infection. The success of these interventions will obviate the need for lifelong antiretroviral therapy, the current standard-of-care, and benefit the millions living today with HIV-1. Mathematical modelling has made significant contributions to these efforts. It has helped elucidate the possible mechanistic origins of natural and post-treatment control, deduced potential pathways of the loss of such control, quantified the effects of interventions, and developed frameworks for their rational optimization. Yet, several important questions remain, posing challenges to the translation of these promising interventions. Here, we survey the recent advances in the mathematical modelling of HIV-1 control and remission, highlight their contributions, and discuss potential avenues for future developments
Pluronic L121-Chrysin conjugated polymeric micelles of exemestane: Improved synergistic effect, in vitro and in vivo anticancer activity
No full textHormonal imbalances, particularly those involving estrogen and progesterone, are strongly associated with the development of breast cancer. Exemestane, an irreversible aromatase inhibitor, is used to treat estrogen-positive breast cancer. However, its clinical effectiveness is hampered by poor water solubility and bioavailability. Additionally, relying solely on a single chemotherapeutic agent often leads to poor therapeutic outcomes. Thus, there is a growing interest in the co-delivery of anticancer drugs, especially those of natural origin. In this study, our aim was to develop and optimize micelles for the simultaneous delivery of Exemestane and Chrysin. Exemestane was incorporated into mixed micelles via physical loading, while chrysin was linked to Pluronic L121 to create CHS-L121. Employing the Box-Benken design of experiments, we investigated the impact of polymer concentration on the independent variable. The optimized mixed micelles exhibited a particle size of 33.04 ± 2.62 nm and a polydispersity index of 0.145 ± 0.02. Notably, these micelles demonstrated excellent drug loading (5.2±2.2 %) and entrapment efficiency (89.6±2.5 %). In addition, CHS-EXE-MMs exhibited significant cytotoxicity against the MCF-7 cell line and showed enhanced in vivo anticancer activity in BALB/c mice. In vivo pharmacokinetic studies further revealed improved bioavailability of EXE and CHS through micelles. Our findings highlight the potential of CHS-EXE-MMs as a promising approach in breast cancer therapy