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Abstract Background The inadvertent observation of a substantial population reduction of greenhouse whiteflies infecting Salvia divinorum plants grown in a polyhouse sparked a flurry of inquiries on the cause of the population decline. The entomopathogenic fungus (EPF) (Alternaria alternata strain VLH1) infecting greenhouse whitefly on S. divinorum plants was isolated and morphologically and molecularly characterised using multilocus sequence typing. Results The fungus was found to be highly virulent against sucking pests; with LC50 values ranging from 1.7 × 104 to 2.5 × 106 spores per ml for the Mustard aphid (Lipaphis erysimi Kaltenbach) and soybean sucking bug (Chauliops choprai Sweet and Schaeffer), respectively. In the lepidopteran larvae treated with a concentration of 3 × 105 spores per ml, the fungus induced developmental abnormalities such as aberrant larval to pupal moulting, defective pupae, and deformed adults. Pathogenicity studies on the two beneficial insects (Coccinella septempunctata (Linn.) and Apis mellifera L.) and 11 host plants revealed no disease signs, indicating that it is safe for use in pest management in hill agriculture. The chitinolytic activity of the fungus and its crude protein extracts was reported in studies conducted against target insect pests, with the highest chitinase enzyme production (117.7 U/ml) on the fourth day of inoculation. Furthermore, over a 96-h period, third instar Helicoverpa armigera (Hubn.) larvae fed on a protein fraction-amended artificial diet showed a significant decrease in nutritional physiology indices such as relative growth rate, relative consumption rate, efficiency of ingested food conversion, efficiency of digested food conversion, and approximate digestibility. Moreover, the polyhouse and open-field studies against two sucking pests; Myzus persicae (Sulz.) infesting capsicum in polyhouse and L. erysimi infesting Indian rapeseed in open-field conditions showed, 81.14% and 63.14% mortality rates, respectively, at 3 × 107 spore/ml concentration. Conclusions Entomopathogenic fungus (EPF) was reported to be an effective biocontrol agent, which caused direct mortality in sucking pests to developmental abnormalities in lepidopteran insects. Despite positive findings in in vitro and in vivo bioassay investigations against various insect pests, the fungus still has to be inspected before it can be used on a broad scale for biological pest management.

The neem tree contains promising pest control substances which are effective against many pests. Oil extracted from neem seeds was used against cardamom thrips, Sciothrips cardamomi, a severe and economic pest of cardamom. Neem oil formulations, namely, Tamil Nadu Agricultural univeristy neem oil (TNAU NO) (acetic acid & citric acid), were found effective against the pest with a overall damage reduction of 30% after 14 days of treatment. The percent damage reduction in capsules over control after three consecutive sprays of TNAU NO(C) 2% and TNAU NO(A) 2% was 78.3 and 75.2 percent, respectively. The newly extracted and unformulated neem oil, though found inferior to the formulated one, still found to cause 50% and 70% reduction in damage caused by thrips at two and three rounds of sprays, making it useful in pest management. Organoleptic tests conducted on cardamom capsules sprayed with neem oil revealed no significant difference in taste, aroma, and overall acceptability of cow milk boiled with cardamom. Thus, TNAU NO (A and C) 2% was found effective against cardamom thrips with no adverse organoleptic properties and can be recommended.

This report builds upon our 2019 analysis that explored how various educational, health, and social factors impact the academic and developmental outcomes of Black students in Los Angeles.We focus on 14 school districts in Los Angeles County that have populations of 800 or more Black students. Collectively, these districts serve two out of three Black students in Los Angeles:ABC Unified School DistrictAntelope Valley Union High School DistrictBellflower Unified School DistrictCentinela Valley Union High School DistrictCompton Unified School DistrictCulver City Unified School DistrictInglewood Unified School DistrictLong Beach Unified School DistrictLos Angeles Unified School DistrictParamount Unified School DistrictPasadena Unified School DistrictPomona Unified School DistrictTorrance Unified School DistrictWilliam S. Hart Union High School DistrictWe cannot ignore the profound impacts COVID-19 is having on Black students and their families. Many are experiencing financial, physical, and emotional hardships associated with job loss, lack of adequate healthcare, and social isolation from prolonged shutdowns. Given that many of the inequities discussed in this report were already pervasive prior to the pandemic, we present our findings along with a set of recommendations for reopening schools and prioritizing the academic success and well-being of Black students with $6 billion in new federal monies available to these 14 school districts.Promising models implemented by districts and schools are offered including descriptions of features and benefits, core objectives, approaches, and practices in support of the social and emotional needs of Black students and families. Finally, we present recommendations for policymakers at all levels of government–city, county, state and federal–that can help to mitigate the disadvantages faced by Black students. While safety remains the number one priority, a more comprehensive approach will be needed to respond to the growing gaps between Black youth and many of their peers. To be clear, schools cannot be expected to do this alone.Learn more on the CTS website.

There are 109,00 Black students in the county, but Black students are overrepresented among those who are underprepared for college, who are subject to punitive forms of discipline, and who are chronically absent from school. Moreover, a disproportionate number of Black students in LA County attend schools that the state has identified as “low-performing” often where critical resources (e.g. school counselors, nurses, social workers, highly qualified teachers, etc.) are in short supply.While considerable attention has been focused on efforts to reform schools and raise student achievement, far less attention and effort has been directed at addressing the out-of-school factors that influence a child’s development, or the social and economic conditions in the neighborhoods where they live. We must do both. Throughout this report, we reference the ways in which the accumulation of disadvantage across various educational, health and social indicators interact with the academic and developmental outcomes of Black children in Los Angeles County. Failure to recognize how poverty, health, and educational performance are related has made it more difficult for education policy to have a positive impact on the needs of the most vulnerable children. This report aims to correct this oversight, suggesting solutions that are designed to counter the effects of these disadvantages. Learn more on the CTS website.

Airborne particles play critical roles in air quality, health effects, visibility, and climate. Secondary organic aerosols (SOA) formed from oxidation of organic gases such as α-pinene account for a significant portion of total airborne particle mass. Current atmospheric models typically incorporate the assumption that SOA mass is a liquid into which semivolatile organic compounds undergo instantaneous equilibrium partitioning to grow the particles into the size range important for light scattering and cloud condensation nuclei activity. We report studies of particles from the oxidation of α-pinene by ozone and NO3 radicals at room temperature. SOA is primarily formed from low-volatility ozonolysis products, with a small contribution from higher volatility organic nitrates from the NO3 reaction. Contrary to expectations, the particulate nitrate concentration is not consistent with equilibrium partitioning between the gas phase and a liquid particle. Rather the fraction of organic nitrates in the particles is only explained by irreversible, kinetically determined uptake of the nitrates on existing particles, with an uptake coefficient that is 1.6% of that for the ozonolysis products. If the nonequilibrium particle formation and growth observed in this atmospherically important system is a general phenomenon in the atmosphere, aerosol models may need to be reformulated. The reformulation of aerosol models could impact the predicted evolution of SOA in the atmosphere both outdoors and indoors, its role in heterogeneous chemistry, its projected impacts on air quality, visibility, and climate, and hence the development of reliable control strategies.

Heterogeneous reactions of sea salt aerosol with various oxides of nitrogen lead to replacement of chloride ion by nitrate ion. Studies of the photochemistry of a model system were carried out using deliquesced mixtures of NaCl and NaNO3 on a Teflon substrate. Varying molar ratios of NaCl to NaNO3 (1 : 9 Cl- : NO3-, 1 : 1 Cl- : NO3-, 3 : 1 Cl- : NO3-, 9 : 1 Cl- : NO3-) and NaNO3 at the same total concentration were irradiated in air at 299 +/- 3 K and at a relative humidity of 75 +/- 8% using broadband UVB light (270-380 nm). Gaseous NO2 production was measured as a function of time using a chemiluminescence NO(y) detector. Surprisingly, an enhanced yield of NO2 was observed as the chloride to nitrate ratio increased. Molecular dynamics (MD) simulations show that as the Cl- : NO3- ratio increases, the nitrate ions are drawn closer to the interface due to the existence of a double layer of interfacial Cl- and subsurface Na+. This leads to a decreased solvent cage effect when the nitrate ion photodissociates to NO2+O*-, increasing the effective quantum yield and hence the production of gaseous NO2. The implications of enhanced NO2 and likely OH production as sea salt aerosols become processed in the atmosphere are discussed.

The photooxidation of 0.6-0.9 ppm alpha-pinene in the presence of a deliquesced thin film of NaNO(3), and for comparison increasing concentrations of NO(2), was studied in a 100 L Teflon(R) chamber at relative humidities from 72-88% and temperatures from 296-304 K. The loss of alpha-pinene and the formation of gaseous products were followed with time using proton transfer mass spectrometry. The yields of gas phase products were smaller in the NaNO(3) experiments than in NO(2) experiments. In addition, pinonic acid, pinic acid, trans-sobrerol and other unidentified products were detected in the extracts of the wall washings only for the NaNO(3) photolysis. These data indicate enhanced loss of alpha-pinene at the NaNO(3) thin film during photolysis. Supporting the experimental results are molecular dynamics simulations which predict that alpha-pinene has an affinity for the surface of the deliquesced nitrate thin film, enhancing the opportunity for oxidation of the impinging organic gas during the nitrate photolysis. This new mechanism of oxidation of organics may be partially responsible for the correlation between nitrate and the organic component of particles observed in many field studies, and may also contribute to the missing source of SOA needed to reconcile model predictions and field measurements. In addition, photolysis of nitrate on surfaces in the boundary layer may lead to oxidation of co-adsorbed organics.