National Academy Science Letters最新文献

This article presents a compact E-shaped wideband bandpass filter with a single notch band. The wideband response of proposed bandpass filter is obtained from E shaped multimode resonator (MMR). A single notched band is obtained by embedded a SIR to suppressed the radio signal fall in passband range. This filter demonstrates a fractional bandwidth of 119.4%. To verify the effectiveness of the design, the filter is fabricated on FR4 with a dielectric constant (ε_r) of 4.4 and a thickness(t) of 1.6 mm. The passband is from 2.43 to 9.63 GHz, with a notch at 5.86 GHz. The designed bandpass filter demonstrates an insertion loss of 1.76 dB and a return loss > 10 dB. The filter has a compact size of 24 mm× 6.52 mm.

In this paper, proposed an algorithm with the name LLCPT, that will trace out the offender/offenders related to a crime. The idea used in this algorithm takes into consideration that, almost everybody uses mobile phones now a days be it basic phone or smart phone. This leads us to notice that, offender/s too may use or carry a mobile phone at or near the site of crime. The LLCPT algorithm works on the principle of earth position and calculate path of mobile.

A culture-free herbal aided assay designed for rapid detection of Extended spectrum β-lactamase producing bacterial isolates in piggery farm and slaughter house waste samples. The assay was validated with 309 piggery farm and slaughterhouse waste samples. The relative accuracy and relative sensitivity of the developed assay was found to be 85.1% and 91.3%, respectively in accordance with the culture based double antibiotic disc diffusion assay as reference method.

A series of indoleninyl-pyrimido[1,2-b]indazoles, including the parent compound 1 and its derivatives (2–4) with different substituents were previously synthesized. However, their precise mode of DNA interactions is still largely unexplored. DNA binding studies revealed that only compound 3 exhibited significant hyperchromism with a binding constant, K_b of 5 × 10⁶ M^− 1, indicating that it strongly binds to the DNA minor groove. As demonstrated from DNA denaturation studies, ionic strength studies, and molecular docking calculations, the minor groove binding ability of 3 was confirmed, with electrostatic and hydrophobic interactions involved in the formation of the DNA adduct. In summary, these preliminary findings from both computational and experimental studies suggested that 3 remains promising for further development as a cytotoxic agent targeting DNA.

The highly unorganized taxonomic data needs to be organised to better understand the taxa. The term ‘taxonomic impediment’ is now widely used to indicate taxonomic research obstacles, one of which is the inadequate accessibility of taxonomic data. Cybertaxonomy, the use of multiple databases of taxonomic information to produce an accurate taxonomy, can help overcome taxonomic impediment. Since taxonomic revision involves organising fragmented data on taxa, the use of cybertaxonomic information can accelerate taxonomic research, especially in India where revision of several plant taxa is still pending. Historically, most of the plants known in India were scientifically discovered by European botanists before Independence, and the original material and other relevant documents are now in Europe. As long as access to these materials is not possible, the taxonomic revision of many plant taxa will not be completed. Cybertaxonomy allows faster and better access to various information, including original material, protologues and literature. Therefore, cybertaxonomic resources have been investigated for their usefulness in the taxonomic revision of plants.

A training workshop on Mangrove Biodiversity Exploration and Restoration at Baikunthapur, Sundarban, West Bengal has been organized by Howrah Vigyan Chetana Samannaya (HVCS), a nodal agency of Vigyan Prasar, Department of Science and Technology, Govt. of India. The programme was technically supported by Directorate of Forest, South 24 Parganas Division, Wildlife Trust of India (WTI), and Department of Environmental Science, University of Calcutta. Research Scholars, Post Graduate and Graduate students from different Universities of India and one student from Germany have attended the workshop. Although Indian Sundarban is recognized as Wetland of International Importance, yet the place is threatened by climate change and anthropogenic activities. Therefore, immediate attention required to conserve its unique biodiversity and restore mangrove plants that can help to sustain the development. Hence, biodiversity conservation and mangrove restoration was the main mission of this workshop. The activities included exploration, understanding the pattern of plant distribution and observation of faunal diversity, interplay of biotic and abiotic factors, mangrove adaptation and behaviour, and mangrove plantation. These activities were conducted under the supervision of resource persons of HVCS, coming from different universities and colleges. Resource persons provided hands-on training to the participants. Students were also encouraged to investigate the socio-economic determinants of the coastal communities, circulating around mangrove forest of Sundarbans. As a result, a capacity-building training for mangrove biodiversity and ecosystem exploration has been implemented. The workshop offered students a deep dive into sustainable use of biodiversity, ensuring the critical need for conservation in Sundarban and other intertidal ecosystem too.

This research focuses on deciphering the phylogenetic relationship between staple cereals, which are crucial for the survival of humans. Our focus has been on the heat shock proteins (HSP) found in cereals, and to achieve this, we have obtained amino acid sequences in FASTA format. By utilizing bioinformatics databases and multiple sequence alignment (MSA) tools, we have compared various sequences to enhance our comprehension. Heat shock proteins (HSP) are activated in plants under heat-stress conditions. Heat stress is a significant abiotic stressor that limits crop production globally. CLUSTAL OMEGA was employed to identify the progressive alignment and phylogeny of the two sequences.The analysis of heat shock protein (HSP) sequences in the selected crop species (wheat, soybean, rice, gram, mustard, and maize) using phylogenetic methods revealed distinct evolutionary relationships. Wheat and soybean were closely clustered together, indicating a recent common ancestor, possibly due to similarities in their HSP sequences. Conversely, rice and gram, despite belonging to different genera, showed a close evolutionary connection, suggesting conserved HSP sequences that point to a shared ancestor. Mustard, while linked to rice and gram, displayed a slightly more distant common ancestor, evident in its longer branch length. Maize, with the longest branch, demonstrated significant evolutionary divergence from the other species, likely attributed to its early divergence in evolutionary history. These findings enhance our understanding of the evolutionary trajectories and the functional conservation of HSPs in these vital crop species.

The Himalayan taxa Begonia gemmipara Hook.f. & Thomson and Celastrus hookeri Prain are collected after a long gap from Darjeeling-Sikkim Himalayan range of India during the floristic assessment of Neora Valley National Park. During identification, it has been noticed that both the names warrant typification for the correct application of name. Hence, the both names are lectotypified here.

The study elucidates the survival of Egeria densa under increasing salinity and the allelopathic effects of the cyanobacterium Microcystis aeruginosa during co-existence. E. densa exhibited a consistent decline in growth with increasing salinity, with the lowest growth observed in a combined culture with M. aeruginosa. Lower salinity levels (up to 2.5 ppt) stimulated chlorophyll pigment synthesis, while higher salinity concentrations inhibited chlorophyll pigment synthesis. E. densa, in monoculture, showed elevated anthocyanin, carotenoid, and H₂O₂ concentrations at higher salinity levels. Conversely, E. densa experienced declining chlorophyll pigment and H₂O₂ concentrations in a combined culture at higher salinity levels. The experiment revealed that freshwater salinity influences the well-being of E. densa co-existing with M. aeruginosa.

Microstructural properties are significantly affected due to structural integrity issues. In present work an attempt has been made to study the effect of S4-C504 filler metal on the microstructural properties of API X70 and SA 516 structural steel dissimilar weld fabricated by metal inert gas welding process (MIG). Microstructure of SA 516 is basically a blend of ferrite and pearlite with grain boundary ferrite films dispersed in ferrite matrix. HAZ microstructure on API X70 side shows the partially unmixed region with some inclusions of ferrite embedded across the grain boundaries. SA516 and APIX70 weld region typically exhibit grain boundary ferrite, widmanstaten-ferrite and bainite as fine needle like structure in the fusion zone of weld metal.