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New particle formation (NPF) in the tropical upper troposphere is a globally important source of atmospheric aerosols1, 2, 3–4. It is known to occur over the Amazon basin, but the nucleation mechanism and chemical precursors have yet to be identified2. Here we present comprehensive in situ aircraft measurements showing that extremely low-volatile oxidation products of isoprene, particularly certain organonitrates, drive NPF in the Amazonian upper troposphere. The organonitrates originate from OH-initiated oxidation of isoprene from forest emissions in the presence of nitrogen oxides from lightning. Nucleation bursts start about 2 h after sunrise in the outflow of nocturnal deep convection, producing high aerosol concentrations of more than 50,000 particles cm−3. We report measurements of characteristic diurnal cycles of precursor gases and particles. Our observations show that the interplay between biogenic isoprene, deep tropical convection with associated lightning, oxidation photochemistry and the low ambient temperature uniquely promotes NPF. The particles grow over time, undergo long-range transport and descend through subsidence to the lower troposphere, in which they can serve as cloud condensation nuclei (CCN) that influence the Earth’s hydrological cycle, radiation budget and climate1,4, 5, 6, 7–8.Aircraft measurements over the Amazon show that new particle formation in the upper troposphere emerges when isoprene, emitted by forests, undergoes oxidation in the presence of nitrogen oxides produced by lightning. [ABSTRACT FROM AUTHOR]

Background: Commiphoracaudatais a traditional medicinal plant which having various medicinal activities but the present research work was focussed on the wound healing activity. The leaves were extracted using continuous hot percolation method. Based on the phytochemical studies, the ethanolic extract was selected for the preparation of herbal tablet. Direct compression was done by making eight batches [F1-F8] of herbal tablets. The pre and post compression studies were investigated for the developed formulation to select optimized one. Aim and objective: The current investigation of the present research is to formulate and develop the herbal tablet from the ethanolic leaf extract of medicinal plant Commiphoracaudata(Wight &Arn.) Engl.and to evaluate the in vitro wound healing studies. Materials and methods: Petroleum ether, Chloroform, Acetone, Ethanol, HPMC, Carbopol, Starch, Lactose monohydrate, Crospovidone, Mannitol, Magnesium stearate, Disodium hydrogen phosphate, Potassium dihydrogen phosphate phosphate which are used for the extraction process and formulation and evaluation of the herbal tablet to analyse the wound healing studies. Result: From this formulation F7 shows the better results than the rest of other formulations and it was subjected for the fibroblast cell line studies(3T3-CCL92) resulted in a significant increase in the percentage from 34.7-53.29% and the dose-response curve produced to be linear which conform the wound healing activity. Then the formulation F7 were carried out for short term accelerated stability studies for 3 months which shows negligible changes. Conclusion: the herbal tablet used for the treatment of wound healing activity as a traditional system of medicine. [ABSTRACT FROM AUTHOR]

Lucknow is the capital of India's largest state, Uttar Pradesh, one of South Asia's most polluted urban cities. Tropospheric photochemistry relies on non-methane volatile organic compounds (NMVOCs), which are ozone and secondary organic aerosol precursors. Using the proton-transfer reaction time of flight mass spectrometer (PTR-ToF-MS) at an urban background site in Lucknow, the chemical characterisation of NMVOCs was performed in real-time from Dec-2020–May 2021. The campaign mean concentrations of the NMVOCs were 125.5 ±37.5 ppbv. The average concentrations of NMVOCs are relatively high during winter. An advanced multi-linear engine (ME-2) model was used to perform the NMVOCs source apportionment using positive matrix factorisation (PMF). It resolves the five main sources contributing to these organic compounds in the atmosphere. They include traffic, two solid fuel combustion factors, secondary volatile organic compounds and volatile chemical products. Biomass burning contributes most to the NMVOCs and SOA formation, while interestingly, traffic sources most influence ozone formation. Significant differences in the composition of the two solid fuel combustion indicate the influence of local emissions and transport of regional pollution to the city. The high temperature during summer leads to more volatilisation of oxygenated VOCs. [ABSTRACT FROM AUTHOR]