Optimization of planting materials for large scale plantation of Bambusa balcooa Roxb.: Influence of propagation methods

AbstractOne of the key insufficiencies of the reports on in vitro propagation of tree species is that the field performances of the in vitro regenerants are not reported in majority of the studies. Although, there are various reports on in vitro propagation of Bambusa balcooa, no report exists on field growth of in vitro regenerants. In the present study we investigated the performance of propagules derived from different in vitro and in vivo propagation methods. B. balcooa Roxb. was propagated through nodal cutting, rhizome splitting and in vitro multiple shoot culture and the performance of plantlets was assessed under field condition for two consecutive years. In vivo propagation through culm cutting was optimized using coarse sand over soil, soil plus sand (1:1; v/v) or vermiculite with >95% survival and 8.2-fold multiplication. In vitro multiple shoot proliferation from nodal segments was achieved on Murashige and Skoog (MS) medium supplemented with 4mgl−1 N6-benzylaminopurine and shoots were successfully rooted on MS plus 1mgl−1 indole-3-butyric acid followed by 100% acclimatization on farmyard manure, soil and sand @ 1:1:1 (v/v) mixture. In the field condition in vitro derived plantlets performed better than the plantlets propagated through nodal cutting or rhizome splitting. Considering the consistent two-year field performance based on plant height, culm characters and internode length it can be concluded that in vitro propagation method would be a better choice instead of in vivo nodal cutting or rhizome splitting techniques for large scale plantation of B. balcooa Roxb

Optimization of planting materials for large scale plantation of Bambusa balcooa Roxb.: Influence of propagation methods

One of the key insufficiencies of the reports on in vitro propagation of tree species is that the field performances of the in vitro regenerants are not reported in majority of the studies. Although, there are various reports on in vitro propagation of Bambusa balcooa, no report exists on field growth of in vitro regenerants. In the present study we investigated the performance of propagules derived from different in vitro and in vivo propagation methods. B. balcooa Roxb. was propagated through nodal cutting, rhizome splitting and in vitro multiple shoot culture and the performance of plantlets was assessed under field condition for two consecutive years. In vivo propagation through culm cutting was optimized using coarse sand over soil, soil plus sand (1:1; v/v) or vermiculite with >95% survival and 8.2-fold multiplication. In vitro multiple shoot proliferation from nodal segments was achieved on Murashige and Skoog (MS) medium supplemented with 4 mg l−1 N6-benzylaminopurine and shoots were successfully rooted on MS plus 1 mg l−1 indole-3-butyric acid followed by 100% acclimatization on farmyard manure, soil and sand @ 1:1:1 (v/v) mixture. In the field condition in vitro derived plantlets performed better than the plantlets propagated through nodal cutting or rhizome splitting. Considering the consistent two-year field performance based on plant height, culm characters and internode length it can be concluded that in vitro propagation method would be a better choice instead of in vivo nodal cutting or rhizome splitting techniques for large scale plantation of B. balcooa Roxb

Shifting seasonality of cyclones and western boundary current interactions in Bay of Bengal as observed during Amphan and Fani

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Sil, S., Gangopadhyay, A., Gawarkiewicz, G., & Pramanik, S. Shifting seasonality of cyclones and western boundary current interactions in Bay of Bengal as observed during Amphan and Fani. Scientific Reports, 11(1), (2021): 22052 https://doi.org/10.1038/s41598-021-01607-6.In recent years, the seasonal patterns of Tropical Cyclones (TC) in the Bay of Bengal have been shifting. While tropical depressions have been common in March–May (spring), they typically have been relatively weaker than the TCs during October–December. Here we show that the spatial pattern of recent warming trends during the last two decades in the southwestern Bay has allowed for stronger springtime pre-monsoon cyclones such as Amphan (May 2020, Super Cyclone) and Fani (April–May 2019, Extremely Severe Cyclone). The tracks of the pre-monsoon cyclones shifted westward, concurrent with an increasing rate of warming. This shift allowed both Fani and Amphan tracks to cross the northeastward warm Western Boundary Current (WBC) and associated warm anti-cyclonic eddies, while the weaker Viyaru (April 2013, Cyclonic Storm) did not interact with the WBC. A quantitative model linking the available along-track heat potential to cyclone’s intensity is developed to understand the impact of the WBC on cyclone intensification. The influence of the warming WBC and associated anti-cyclonic eddies will likely result in much stronger springtime TCs becoming relatively common in the future.The authors gratefully acknowledge the financial and infrastructural support from the Indian Institute of Technology Bhubaneswar to carry out this research. SS acknowledges the financial assistance from Science and Engineering Research Board (SERB), Government of India (Grant No. CRG/2019/005842). All the figures are prepared using MATLAB. AG and SS appreciate the support of SERB's VAJRA Faculty Scheme (VJR/2018/000108) for the initiation of this collaborative work between SMAST and IITBBS. AG also acknowledges partial support from NSF (OCE 1851242) in completing this manuscript. GG was supported by a Grant from the Office of Naval Research as part of the Task Force Ocean initiative

Role of interannual equatorial forcing on the subsurface temperature dipole in the Bay of Bengal during IOD and ENSO events

Role of equatorial forcing on the thermocline variability in the Bay of Bengal (BoB) during positive and negative phases of the Indian Ocean Dipole (IOD) and El Niño Southern Oscillation (ENSO) was investigated using the Regional Ocean Modeling System (ROMS) simulations during 1988 to 2015. Two numerical experiments were carried out for (i) the Indian Ocean Model (IOM) with interannual open boundary conditions and (ii) the BoB Model (BoBM) with climatological boundary conditions. The first mode of Sea Surface Height Anomalies (SSHA) variability showed a west-east dipole nature in both IOM and altimetry observations around 11°N, which was absent in the BoBM. The vertical section of temperature along the same latitude showed a sharp subsurface temperature dipole with a core at ~ 100 m depth. The positive (negative) subsurface temperature anomalies were observed over the whole northeastern BoB during NIOD (PIOD) and LN (EN) composites due to stronger (weaker) second downwelling Kelvin Waves. During the negative phases of IOD and ENSO, the cyclonic eddy on the southwestern BoB strengthened due to intensified southward coastal current along the western BoB and local wind stress. The subsurface temperature dipole was at its peak during October–December (OND) with 1-month lag from IOD and was evident from the Argo observations and other reanalysis datasets as well. A new BoB dipole index (BDI) was defined as the normalized difference of 100-m temperature anomaly and found to be closely related to the frequency of cyclones and the surface chlorophyll-a concentration in the BoB

Active metasurface-based wideband polarization converter with a switchable notch

We introduce a new metasurface-based wideband polarization converter with a switchable notch band. Unlike previous structures, the proposed structure utilizes the properties of p-i-n diodes to offer switchable functionalities between single/dual-frequency bands. Specifically, during the on-state of diodes, an incident linearly polarized (LP) plane wave of frequency range 4.87-11.41 GHz is converted into an orthogonally linearly polarized (OLP) wave. Conversely, when the p-i-n diodes are set in their off-state, the structure converts the LP plane wave into an OLP wave within two adjacent frequency bands (4.80-7.31 GHz and 9.82-11.43 GHz) separated by a notch region (7.44-7.55 GHz). The notch band is characterized by an LP-full reflection behavior that can be exploited for stealth antenna applications. The working principle of the proposed device and its physical mechanisms are discussed. Finally, a prototype is fabricated and measured and the experimental results confirm the effectiveness of the proposed structure

Active metasurface based reconfigurable polarization converter with multiple and simultaneous functionalities

We introduce a new concept of three-states polarization converting metasurface (TS-PCM) based on p-i-n diodes. The proposed structure can offer three distinct wave manipulation functionalities: linear polarization to orthogonal linear polarization (LP-OLP), linear polarization to circular polarization (LP-CP), and linear polarization to full reflection (LP-FR) state. Unlike previous structures, the multiple conversion features are simultaneously achieved in different frequency ranges, depending on the operating state of diode (off or on). Finally, a sample prototype was fabricated and the experimental results were verified with the simulated ones

AN INVENTORY OF NECROPHAGOUS FLIES FROM INDIA

India has experienced an increase in violent murder cases in recent years. In 2021, there were over 29 thousand murders reported across India. Furthermore, more than 55 thousand attempted murder cases were filed in the country that year. A consistent increase in attempted murder cases was seen over the years till 2017. The reasons for death have been elucidated using necrophagous fly data in recent years. Forensic entomology focuses on the close bond between insects and corpses in addition to the use of insects in medicolegal investigations and as well as necrophagous flies play a crucial role in the decay of corpses. A checklist of necrophagous flies from India is hence provided. A total of 349 species belonging to 56 genera under 16 families are documented in this list along with their details of distribution. This is the first checklist of necrophagous flies from India which gives the complete scenario of the diversity of such flies from this megadiverse country. This checklist might serve as a new source of data on criminal cases and wildlife poaching in India

NSAID targets SIRT3 to trigger mitochondrial dysfunction and gastric cancer cell death

Summary: Gastric cancer (GC) is a deadly malignancy that demands effective therapeutic intervention capitalizing unique drug target/s. Here, we report that indomethacin, a cyclooxygenase non-selective non-steroidal anti-inflammatory drug, arrests GC cell growth by targeting mitochondrial deacetylase Sirtuin 3 (SIRT3). Interaction study revealed that indomethacin competitively inhibited SIRT3 by binding to nicotinamide adenine dinucleotide (NAD)-binding site. The Cancer Genome Atlas data meta-analysis indicated poor prognosis associated with high SIRT3 expression in GC. Further, transcriptome sequencing data of human gastric adenocarcinoma cells revealed that indomethacin treatment severely downregulated SIRT3. Indomethacin-induced SIRT3 downregulation augmented SOD2 and OGG1 acetylation, leading to mitochondrial redox dyshomeostasis, mtDNA damage, respiratory chain failure, bioenergetic crisis, mitochondrial fragmentation, and apoptosis via blocking the AMPK/PGC1α/SIRT3 axis. Indomethacin also downregulated SIRT3 regulators ERRα and PGC1α. Further, SIRT3 knockdown aggravated indomethacin-induced mitochondrial dysfunction as well as blocked cell-cycle progression to increase cell death. Thus, we reveal how indomethacin induces GC cell death by disrupting SIRT3 signaling