40 research outputs found

    Development of mixed anaerobic culture for degrading high concentrations of chlorophenols

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    This study details the development of mixed anaerobic culture capable of degrading high concentrations of chlorophenols; 4-chlorophenol (MCP), 2,4-dichlorophenol (DCP) and pentachlorophenol (PCP) were used for that purpose. The role of glucose concentration and the relative potential of mixed culture for acclimatization of different chlorophenols under anaerobic conditions were studied. Methane production, pH and their reduction in concentrations of glucose and chlorophenols were measured at regular intervals. It was observed that after 350 days of acclimatization, anaerobic cultures degraded up to 200 ppm MCP, 200 ppm DCP and 250 ppm PCP. It was also found that the biogenic substrate such as glucose increased the rate of chlorophenols acclimatization and degradation

    Rapid growth and high cloud-forming potential of anthropogenic sulfate aerosol in a thermal power plant plume during COVID lockdown in India

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    The COVID lockdown presented an interesting opportunity to study the anthropogenic emissions from different sectors under relatively cleaner conditions in India. The complex interplays of power production, industry, and transport could be dissected due to the significantly reduced influence of the latter two emission sources. Here, based on measurements of cloud condensation nuclei (CCN) activity and chemical composition of atmospheric aerosols during the lockdown, we report an episodic event resulting from distinct meteorological conditions. This event was marked by rapid growth and high hygroscopicity of new aerosol particles formed in the SO2 plume from a large coal-fired power plant in Southern India. These sulfate-rich particles had high CCN activity and number concentration, indicating high cloud-forming potential. Examining the sensitivity of CCN properties under relatively clean conditions provides important new clues to delineate the contributions of different anthropogenic emission sectors and further to understand their perturbations of past and future climate forcing

    Isoprene Suppression of New Particle Formation in a Mixed Deciduous Forest

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    Production of new particles over forests is an important source of cloud condensation nuclei that can affect climate. While such particle formation events have been widely observed, their formation mechanisms over forests are poorly understood. Our observations made in a mixed deciduous forest with large isoprene emissions during the summer displayed a surprisingly rare occurrence of new particle formation (NPF). Typically, NPF events occur around noon but no NPF events were observed during the 5 weeks of measurements. The exceptions were two evening ultrafine particle events. During the day, sulfuric acid concentrations were in the 106 cm−3 range with very low preexisting aerosol particles, a favorable condition for NPF to occur even during the summer. The ratio of emitted isoprene carbon to monoterpene carbon at this site was similar to that in Amazon rainforests (ratio >10), where NPF events are also very rare, compared with a ratio <0.5 in Finland boreal forests, where NPF events are frequent. Our results suggest that large isoprene emissions can suppress NPF formation in forests although the underlying mechanism for the suppression is unclear. The two evening ultrafine particle events were associated with the transported anthropogenic sulfur plumes and ultrafine particles were likely formed via ion-induced nucleation. Changes in landcover and environmental conditions could modify the isoprene suppression of NPF in some forest regions resulting in a radiative forcing that could have influence on the climate.</p

    Infrequent occurrence of new particle formation at a semi-rural location, Gadanki, in tropical Southern India

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    We report first measurements of ultrafine particles from a semi-rural location, Gadanki, from tropical Southern India. Measurements of particle number size distributions in the diameter range of 5 nm-32 mu m were performed during 2 May-31 July 2012. The mean number concentrations of nucleation (N-NUC), Aitken (N-AIT), accumulation (N-ACCU), and total particles (N-TOT) at this site were (1.1 +/- 0.9) x 10(3) cm(-3), (2.2 +/- 1.3) x 10(3) cm(-3), (1.5 +/- 1.2) x 10(3) cm(-3) and (4.8 +/- 2.4) x 10(3) cm(-3), respectively, comparable to other rural to semi-rural locations globally and declined as the season progressed, perhaps due to wet removal of aerosols with onset of monsoon in early June. Particle bursts in the nucleation mode size range (5-25 nm), followed by a sustained growth in size were observed very rarely (only 5 out of 79 observation days) at this site, less frequently than at most other locations around the world during May-July. Most factors affecting new particle formation (NPF) were similar on NPF and nonNPF event days, such as condensation sink, relative humidity, temperature, wind speed and direction, and mixing layer height. Thus, the infrequent occurrence of NPF at our site appeared to be linked to lower precursor gas concentrations and weak gas-phase oxidation chemistry due to diminished solar radiation on persistently cloudy days with the onset of the monsoon in early June over this region. The derived particle growth rates (GR > 5 nm) and formation rates of 5 nm particles (J(5)) ranged from 2.2 to 4.7 nm h(-1) and 0.4-2.4 cm(-3) s(-1), with a mean and standard deviation of 3.4 +/- 0.9 nm h(-1) and 12 +/- 2.3 cm(-3) s(-1), respectively, comparable to previous investigations at rural to semi-rural locations. The observed behavior in aerosol and meteorological parameters on NPF and nonNPF event days appeared to be distinctive compared to other rural to urban locations across the globe. However, this distinct behavior is limited and restricted to this site and season of the year, and should therefore not be generalized over a larger spatio-temporal scale. This emphasizes the need for long-term aerosol and precursor measurements over this and other regions of India. (C) 2014 Elsevier Ltd. All rights reserved

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    Not AvailableSorghum [ (L.) Moench] is a very important crop in the arid and semi-arid tropics of India and African subcontinent. In the process of release of new cultivars using multi-location data major emphasis is being given on the superiority of the new cultivars over the ruling cultivars, while very less importance is being given on the genotype x environment interaction (GEI). In the present study, performance of ten Indian hybrids over 12 locations across the rainy seasons of 2008 and 2009 was investigated using GGE biplot analysis. Location attributed higher proportion of the variation in the data (59.3-89.9%), while genotype contributed only 3.9-16.8% of total variation. Genotype x location interaction contributed 5.8-25.7% of total variation. We could identify superior hybrids for grain yield, fodder yield and for harvest index using biplot graphical approach effectively. Majority of the testing locations were highly correlated. 'Which-won-where' study partitioned the testing locations into three mega-environments: first with eight locations with SPH 1606/1609 as the winning genotypes; second mega-environment encompassed three locations with SPH 1596 as the winning genotype, and last mega-environment represented by only one location with SPH 1603 as the winning genotype. This clearly indicates that though the testing is being conducted in many locations, similar conclusions can be drawn from one or two representatives of each mega-environment. We did not observe any correlation of these mega-environments to their geographical locations. Existence of extensive crossover GEI clearly suggests that efforts are necessary to identify location-specific genotypes over multi-year and -location data for release of hybrids and varieties rather focusing on overall performance of the entries.Not Availabl

    Characteristics of COVID-19 patients with multiorgan injury across the pandemic in a large academic health system in the Bronx, New York

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    Purpose: To investigate the evolution of COVID-19 patient characteristics and multiorgan injury across the pandemic. Methods: This retrospective cohort study consisted of 40,387 individuals tested positive for SARS-CoV-2 in the Montefiore Health System in Bronx, NY, between March 2020 and February 2022, of which 11,306 were hospitalized. Creatinine, troponin, and alanine aminotransferase were used to define acute kidney injury (AKI), acute cardiac injury (ACI) and acute liver injury, respectively. Demographics, comorbidities, emergency department visits, hospitalization, intensive care utilization, and mortality were analyzed across the pandemic. Results: COVID-19 positive cases, emergency department visits, hospitalization and mortality rate showed four distinct waves with a large first wave in April 2020, two small (Alpha and Delta) waves, and a large Omicron wave in December 2021. Omicron was more infectious but less lethal (p = 0.05). Among hospitalized COVID-19 patients, age decreased (p = 0.014), female percentage increased (p = 0.023), Hispanic (p = 0.028) and non-Hispanic Black (p = 0.05) percentages decreased, and patients with pre-existing diabetes (p = 0.002) and hypertension (p = 0.04) decreased across the pandemic. More than half (53.1%) of hospitalized patients had major organ injury. Patients with AKI, ACI and its combinations were older, more likely males, had more comorbidities, and consisted more of non-Hispanic Black and Hispanic patients (p = 0.005). Patients with AKI and its combinations had 4-9 times higher adjusted risk of mortality than those without. Conclusions: There were shifts in demographics toward younger age and proportionally more females with COVID-19 across the pandemic. While the overall trend showed improved clinical outcomes, a substantial number of COVID-19 patients developed multi-organ injuries over time. These findings could bring awareness to at-risk patients for long-term organ injuries and help to better inform public policy and outreach initiatives
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