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Many farmer-popular indica rice (Oryza sativa L.) cultivars are recalcitrant to Agrobacterium-mediated transformation through tissue culture and regeneration. In planta transformation using Agrobacterium could therefore be a useful alternative for indica rice. A simple and reproducible in planta protocol with higher transformation efficiencies than earlier reports was established for a recalcitrant indica rice genotype. Agrobacterium tumefaciens containing the salt tolerance-enhancing Pea DNA Helicase45 (PDH45) gene, with the reporter and selectable marker genes, gus-INT (β-glucuronidase with intron) and hygromycin phosphotransferase (hpt), respectively, were used. Overnight-soaked mature embryos were infected and allowed to germinate, flower, and set T1 seeds. T0 plants were considered positive for the transgene if the spikelets of one or more of their panicles were positive for gus. Thereafter, selection at T1 was done by germination in hygromycin and transgenic status re-confirmation by subjecting plantlet DNA/RNA to gene-specific PCR, Southern and semi-quantitative RT-PCR. Additionally, physiological screening under saline stress was done at the T2 generation. Transformation efficiency was found to be 30-32% at the T0 generation. Two lines of the in planta transformed seedlings of the recalcitrant rice genotype were shown to be saline tolerant having lower electrolyte leakage, lower Na+/K+, minimal leaf damage, and higher chlorophyll content under stress, compared to the WT at the T2 generation. [ABSTRACT FROM AUTHOR]

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Background: Extreme hyperbilirubinemia leading to neurologic disability and death is disproportionately higher in low- and middle-income countries (LMIC) such as Bangladesh, and is largely preventable through timely treatment. In LMICs, an estimated half of all newborns are born at home and few receive screening or treatment for hyperbilirubinemia, leading to 6 million newborns per year who need phototherapy treatment for hyperbilirubinemia but are untreated. Household screening and treatment for neonatal hyperbilirubinemia with phototherapy administered by a trained community health worker (CHW) may increase indicated treatment for neonatal hyperbilirubinemia in comparison to the existing care system in Bangladesh., Methods: 530 Bangladeshi women in their second or third trimester of pregnancy from the rural community of Sakhipur, Bangladesh will be recruited for a cluster randomized trial and randomized to the intervention arm - home screening and treatment for neonatal hyperbilirubinemia - or the comparison arm to receive usual care. In the intervention arm, CHWs will provide mothers with two prenatal visits, visit newborns by 2 days of age and then daily for 3 days to measure transcutaneous bilirubin (TcB) and monitor for clinical danger signs. Newborns without danger signs but with a TcB above the treatment threshold, but >15 mg/dL will be treated with light-emitting diode (LED) phototherapy at home. Newborns with danger signs or TcB ≥15 mg/dL will be referred to a hospital for treatment. Treatment rates for neonatal hyperbilirubinemia in each arm will be compared., Conclusion: This study will evaluate the effectiveness of CHW-led home phototherapy to increase neonatal hyperbilirubinemia treatment rates in rural Bangladesh. LMICs are expanding access to postnatal care by using CHWs, and our work will give CHWs a curative treatment option for neonatal hyperbilirubinemia. Similar projects in other LMICs can be pursued to dramatically extend healthcare access to vulnerable newborns with hyperbilirubinemia., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Foote EM et al.)

Exploration of the full potential of the perovskite nanocrystals (NCs) for different applications requires a thorough understanding of the pathways of recombination of the photogenerated charge carriers and associated dynamics. In this work, we have tracked the recombination routes of the charge carriers by probing photoluminescence (PL) intermittency of the immobilized and freely diffusing single CsPbBr 3 NCs employing a time-tagged-time-resolved method. The immobilized single CsPbBr 3 NCs show a complex PL time-trace, a careful analysis of which reveals that nonradiative band-edge recombination through trap states, trion recombination, and trapping of the hot carriers contribute to the blinking behavior of any given NC. A drastically suppressed PL blinking observed for the NCs treated with a tetrafluoroborate salt indicates elimination of most of the undesired recombination processes. A fluorescence correlation spectroscopy (FCS) study on the freely diffusing single NCs shows that enhanced PL and suppressed blinking of the treated particles are the outcome of an increase in per-particle brightness, not due to any increase in the number of particles undergoing "off"-"on" transition in the observation volume. The mechanistic details obtained from this study on the origin of blinking in CsPbBr 3 NCs provide deep insight into the radiative and nonradiative charge carrier recombination pathways in these important materials, and this knowledge is expected to be useful for better design and development of bright photoluminescent samples of this class for optoelectronic applications.

To obtain an in-depth understanding of the dynamics and mechanism of carrier recombination in CsPbBr 3 nanocrystals (NCs), we have investigated the photoluminescence (PL) of this material at the single-particle level using the time-tagged-time-resolved method. The study reveals two distinct types of PL fluctuations of the NCs, which are assigned to flickering and blinking. The flickering is found to be due to excess surface trap on the NCs, and the flickering single particles are transformed into blinking ones with significant enhancement of PL intensity and stability on postsynthetic surface treatment. Intensity-correlated lifetime analysis of the PL time trace reveals both trap-mediated nonradiative band-edge carrier recombination and positive trion recombination in single NCs. Dynamical and statistical analysis suggests a diffusive nature of the trap states to be responsible for the PL intermittency of the system. These findings throw light on the nature of the trap states, reveal the manifestation of these trap states in PL fluctuation, and provide an effective way to control the dynamics of CsPbBr 3 NCs.