Effect of High Temperature and Low Rainfall on Quantity and Quality of Sri Lanka Dwarf Green Female Flowers That Are Used for Controlled Hybridization in Coconut (Cocos nucifera L.)

Development of climate resilient hybrid coconut cultivars is an important strategy to increase the coconut yield in changing climate. To accomplish this, understanding the impacts of heat and drought stress (HTDS) on reproductive organs of coconut plays a vital role. Accordingly, this study was conducted to assess the impact of HTDS on the quantity and quality (weight and carbohydrate accumulation) of female flowers in Sri Lanka Green Dwarf (SLGD) palms that are used as female parent of hybrids CRIC65 and Kapruwana. The study mainly focused, HTDS during the four month period prior to inflorescence opening (0 stage; month of inflorescence opening, -1; 1st (embryo sac formation), -2; 2nd (meiosis) and -3; 3rd (ovule development) month prior to inflorescence opening) on quantity and quality of the female flowers. The experiment was conducted in Ambakelle and Pallama seed gardens of Coconut Research Institute of Sri Lanka from September 2013 to June 2015. The study revealed that water stress prevailed at -2 stage reduced female flower production by 33% - 45% compared to non- stressed flowers, irrespective of the heat and/or water stress prevailed in other development stages (p<0.05). Further, weight of the female flowers reduced by about 50% when they experienced continuous water stress during -3, -2 and -1 stages compared to non-stressed flowers. The water stress combined with heat stress at -3 stage, reduced starch content by 90% and total soluble sugars (TSS) by 33% compared to non stressed flowers. However, inflorescences experienced HTDS at 0 stage depleted starch by 65% whilst increased TSS by 26% compared to non stressed flowers. Carbohydrate content in female reproductive tissues at the receptive stage is important for growth of pollen tube after pollination. Fluctuation of the carbohydrates may impair the fertilization process. Therefore, knowledge on sensitivity of female flowers to stress is important to develop pollination strategies to minimize drought induced fruit set failures in hybrid seed production.Keywords: Coconut inflorescence, Flower carbohydrates, Heat, Water stres

New constraints on ultraheavy dark matter from the LZ experiment

Searches for dark matter with liquid xenon time projection chamber experiments have traditionally focused on the region of the parameter space that is characteristic of weakly interacting massive particles, ranging from a few GeV/c2 to a few TeV/c2. Models of dark matter with a mass much heavier than this are well motivated by early production mechanisms different from the standard thermal freeze-out, but they have generally been less explored experimentally. In this work, we present a reanalysis of the first science run of the LZ experiment, with an exposure of 0.9  tonne×yr, to search for ultraheavy particle dark matter. The signal topology consists of multiple energy deposits in the active region of the detector forming a straight line, from which the velocity of the incoming particle can be reconstructed on an event-by-event basis. Zero events with this topology were observed after applying the data selection calibrated on a simulated sample of signal-like events. New experimental constraints are derived, which rule out previously unexplored regions of the dark matter parameter space of spin-independent interactions beyond a mass of 1017  GeV/c2. Published by the American Physical Society 2024 </jats:sec

Possibility and challenges of conversion of current virus species names to Linnaean binomials

Botanical, mycological, zoological, and prokaryotic species names follow the Linnaean format, consisting of an italicized Latinized binomen with a capitalized genus name and a lower case species epithet (e.g., Homo sapiens). Virus species names, however, do not follow a uniform format, and, even when binomial, are not Linnaean in style. In this thought exercise, we attempted toconvert all currently official names ofspecies included in the virusfamily Arenaviridae and the virus order Mononegavirales to Linnaean binomials, and to identify and address associated challenges and concerns. Surprisingly, this endeavor was not as complicated or time-consuming as even the authors of this article expected when conceiving the experiment

Cosmogenic production of Ar 37 in the context of the LUX-ZEPLIN experiment

© 2022 authors. Published by the American Physical Society.We estimate the amount of Ar37 produced in natural xenon via cosmic-ray-induced spallation, an inevitable consequence of the transportation and storage of xenon on the Earth&apos;s surface. We then calculate the resulting Ar37 concentration in a 10-tonne payload (similar to that of the LUX-ZEPLIN experiment) assuming a representative schedule of xenon purification, storage, and delivery to the underground facility. Using the spallation model by Silberberg and Tsao, the sea-level production rate of Ar37 in natural xenon is estimated to be 0.024 atoms/kg/day. Assuming the xenon is successively purified to remove radioactive contaminants in 1-tonne batches at a rate of 1 tonne/month, the average Ar37 activity after 10 tons are purified and transported underground is 0.058-0.090 μBq/kg, depending on the degree of argon removal during above-ground purification. Such cosmogenic Ar37 will appear as a noticeable background in the early science data, while decaying with a 35-day half-life. This newly noticed production mechanism of Ar37 should be considered when planning for future liquid-xenon-based experiments.11Nsciescopu

A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics

The nature of dark matter and properties of neutrinos are among the most pressing issues in contemporary particle physics. The dual-phase xenon time-projection chamber is the leading technology to cover the available parameter space for Weakly Interacting Massive Particles (WIMPs), while featuring extensive sensitivity to many alternative dark matter candidates. These detectors can also study neutrinos through neutrinoless double-beta decay and through a variety of astrophysical sources. A next-generation xenon-based detector will therefore be a true multi-purpose observatory to significantly advance particle physics, nuclear physics, astrophysics, solar physics, and cosmology. This review article presents the science cases for such a detector

A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics

The nature of dark matter and properties of neutrinos are among the most pressing issues in contemporary particle physics. The dual-phase xenon time-projection chamber is the leading technology to cover the available parameter space for Weakly Interacting Massive Particles (WIMPs), while featuring extensive sensitivity to many alternative dark matter candidates. These detectors can also study neutrinos through neutrinoless double-beta decay and through a variety of astrophysical sources. A next-generation xenon-based detector will therefore be a true multi-purpose observatory to significantly advance particle physics, nuclear physics, astrophysics, solar physics, and cosmology. This review article presents the science cases for such a detector

A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics

The nature of dark matter and properties of neutrinos are among the most pressing issues in contemporary particle physics. The dual-phase xenon time-projection chamber is the leading technology to cover the available parameter space for Weakly Interacting Massive Particles (WIMPs), while featuring extensive sensitivity to many alternative dark matter candidates. These detectors can also study neutrinos through neutrinoless double-beta decay and through a variety of astrophysical sources. A next-generation xenon-based detector will therefore be a true multi-purpose observatory to significantly advance particle physics, nuclear physics, astrophysics, solar physics, and cosmology. This review article presents the science cases for such a detector