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Effects of eccentricity and horizontal electric field (EH) on the binary‐collision outcomes of water drops are examined using numerically calculated collision characteristics from previous studies and results of simulation experiment conducted by the authors. For a fixed collision kinetic energy (CKE), filament breakups can occur at all values of eccentricity but events of coalescence decrease, and that of sheet breakup increase with increasing eccentricity in absence of EH. However, as EH increases to ∼300 kVm−1 it opposes the variability of the coalescence and sheet breakup events with eccentricity. When EH exceeds ∼300 kVm−1 the collision outcomes might be determined only by the CKE and EH. The calculated value of coalescence efficiency and total number of fragments after a binary collision decreases with an increase in EH. It is argued that an electric field can significantly modify drop size distribution in thunderclouds and needs to be considered for development of precipitation. Plain Language Summary: Growth of water drops in clouds is mostly governed by the drop size distribution in them. When two drops collide with each other, they can either coalesce to form a single larger drop, or disintegrate into many smaller drops, or bounce back. These different outcomes after their collisions are mostly determined by whether the collisions are centric where the eccentricity of the collision is zero or grazing where the eccentricity is one or somewhere in between the two extremes. The present study shows that if the collisions occur in presence of a horizontal electric field, it opposes the effect of eccentricity on the outcomes of the collisions. In this study, simultaneous effects of eccentricity and horizontal electric field are examined from numerically calculated collision characteristics from previous studies and utilizing the results of a simulation experiment recently conducted by the authors. Simultaneous effects of eccentricity and electric field on coalescence efficiency and total and spectral size distribution of fragments generated after the collision have also been evaluated. The results suggest that the electric field can significantly modify drop size distribution in thunderclouds and need to be considered for the development of precipitation. Key Points: Horizontal electric field opposes the variability of coalescence/sheet breakup of water drops with eccentricity in binary collisionsNumber of fragments close to small (large) parent drop size decreases (increases) after collisions in the higher horizontal electric fieldBinary collisions in horizontal electric fields can substantially modify drop size distribution in thunderclouds [ABSTRACT FROM AUTHOR]

Phasor Measurement Units (PMUs) have emerged as crucial tools in the field of power system monitoring, control, and safety. Extensive research has been conducted on enhancing the capabilities of PMUs. Traditional SCADA techniques, which have been employed for many years, gather data on power system parameters at intervals of 4 to 10 seconds, offering a static perspective of the system's behavior. However, relying solely on static data may limit the effectiveness of the monitoring and control. On the other hand, PMUs provide real-time information about the dynamic state of the system, enabling more comprehensive insights. For the optimal and cost-effective installation of PMUs, it is vital to strategically position them in locations that effectively monitor the state of the system. The Instruction Level Parallelism (ILP) approach was employed to identify the ideal PMU placement for power system observability. The ILP approach determines the most suitable positions for PMUs by considering factors such as the redundancy of measurements and cost efficiency. To validate the effectiveness of the ILP approach, it was tested using the widely recognized IEEE 14 bus system, which serves as a standard benchmark for power-system analysis. Through the ILP approach, the optimal placement of the PMUs can be determined, thereby enhancing the observability of the power system. This in turn improves situational awareness, enables effective fault detection, and facilitates coordinated control strategies. By integrating PMUs and the ILP approach, the power system monitoring and control can be significantly enhanced. Ongoing research and development in PMU technology and placement methodologies continues to advance the field, enabling more efficient and effective management of modern power grids. [ABSTRACT FROM AUTHOR]

The seasonal and inter annual variability of Tropospheric Nitrogen dioxide (NO2), Ozone (O3) and lightning activity over Maharashtra and adjoining part of states (15.5°N-22.5°N, 72.5°E-81.5°E) of India, is analyzed to study the role of lightning activity in the seasonal variation of NO2and O3. Satellite observations of Tropospheric NO2and O3from Aura- Ozone Monitoring Instrument (OMI)/Microwave Limb Sounder (MLS) for the period 2005–2016 and lightning data of 2014–2016 from lightning detection network over Maharashtra are used for analysis. Analyses show that the seasonal variations of all the three quantities are closely related to each other. The scatter plot between monthly NO2concentration verses monthly lightning activity for years 2014–2016 also show good correlation between these two parameters (r = 0.71, significant at 99.9%). Our analysis demonstrates that the seasonal and inter-annual variations in NO2and O3are affecting by lightning activity over study region. However, biomass burning during April-May and increased air pollution during winter months (November-January) also play important role in the intra seasonal variations of NO2and O3over this region. [ABSTRACT FROM AUTHOR]

This paper describes the characterisation of a new family of higher plant nuclear envelope-associated proteins (NEAPs) that interact with other proteins of the nuclear envelope. In the model plant Arabidopsis thaliana, the family consists of three genes expressed ubiquitously (AtNEAP1–3) and a pseudogene (AtNEAP4). NEAPs consist of extensive coiled-coil domains, followed by a nuclear localisation signal and a C-terminal predicted transmembrane domain. Domain deletion mutants confirm the presence of a functional nuclear localisation signal and transmembrane domain. AtNEAP proteins localise to the nuclear periphery as part of stable protein complexes, are able to form homo- and heteromers, and interact with the SUN domain proteins AtSUN1 and AtSUN2, involved in the linker of nucleoskeleton and cytoskeleton (LINC) complex. An A. thaliana cDNA library screen identified a putative transcription factor called AtbZIP18 as a novel interactor of AtNEAP1, which suggest a connection between NEAP and chromatin. An Atneap1 Atneap3 double-knockout mutant showed reduced root growth, and altered nuclear morphology and chromatin structure. Thus AtNEAPs are suggested as inner nuclear membrane-anchored coiled-coil proteins with roles in maintaining nuclear morphology and chromatin structure. [ABSTRACT FROM AUTHOR]