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The Kingdom of Bhutan in the Eastern Himalayas harbors a rich biodiversity. However, its detailed documentation still needs to be created, including not only macroorganisms but also protists. In the present study, as many as 105 taxa of testate amoebae were identified and directly counted in soil suspension samples collected from the wetlands of the Gangtey-Phobji Valley (generally Phobjikha), Wangdue Phodrang district. The most dominant were cosmopolitan species, e.g., Euglypha rotunda , Trinema lineare , T. complanatum , T. enchelys , Phryganella acropodia , and Plagiopyxis declivis. However, some taxa such as Centropyxis deflandriana, C. stenodeflandriana , Hoogenraadia cf. humicola , Pareuglypha reticulata , and Sphenoderia chardezi have a geographically restricted distribution and/or are considered rare. Some specimens could not be assigned to already described species (Centropyxis dentata sp. nov. and Difflugia fusiforma sp. nov.) or were highly similar to known species but differed in size or other taxonomically important characteristics (e.g., Hoogenraadia cf. humicola and Planhoogenraadia sp.). To our knowledge, this study is the first to present a comprehensive list of testate amoebae from Bhutan, including some new and rare species. The discovery of a remarkable diversity of testate amoebae in only a few soil samples suggests that this remote and largely unexplored region likely harbors many more intriguing species. [ABSTRACT FROM AUTHOR] more...

• Peer production has been hailed as a pathway towards post-capitalist futures. • Peer production suffers from rigid hierarchies, power asymmetries and gender imbalances. • Peer production may democratize technology when centered around the commons. • Through scaling-wide or -out, peer production projects may address their organizational issues and tackle climate change. Over the last decade, a discussion about the limits of peer production has opened. On the one hand, some scholars consider peer production as a new path of value creation that could lead to an alternative form of social organization. On the other, critics claim that peer production is not emancipatory, but in fact suffers from rigid hierarchies, participation inequality, power asymmetries, and gender imbalance. Moreover, they argue that peer production depends on the capitalist economy for its reproduction and thus that its post-capitalist potential is very limited. This article summarizes and reviews the criticism against the emancipatory potential of peer production and proposes ways in which peer production could still democratize technology and society. [ABSTRACT FROM AUTHOR] more...

There is a body of evidence that ultrafine particles (UFP, those with diameters ≤ 100 nm) might have significant impacts on health. Accordingly, identifying sources of UFP is essential to develop abatement policies. This study focuses on urban Europe, and aims at identifying sources and quantifying their contributions to particle number size distribution (PNSD) using receptor modelling (Positive Matrix Factorization, PMF), and evaluating long-term trends of these source contributions using the non-parametric Theil-Sen's method. Datasets evaluated include 14 urban background (UB), 5 traffic (TR), 4 suburban background (SUB), and 1 regional background (RB) sites, covering 18 European and 1 USA cities, over the period, when available, from 2009 to 2019. Ten factors were identified (4 road traffic factors, photonucleation, urban background, domestic heating, 2 regional factors and long-distance transport), with road traffic being the primary contributor at all UB and TR sites (56-95 %), and photonucleation being also significant in many cities. The trends analyses showed a notable decrease in traffic-related UFP ambient concentrations, with statistically significant decreasing trends for the total traffic-related factors of -5.40 and -2.15 % yr -1 for the TR and UB sites, respectively. This abatement is most probably due to the implementation of European emissions standards, particularly after the introduction of diesel particle filters (DPFs) in 2011. However, DPFs do not retain nucleated particles generated during the dilution of diesel exhaust semi-volatile organic compounds (SVOCs). Trends in photonucleation were more diverse, influenced by a reduction in the condensation sink potential facilitating new particle formation (NPF) or by a decrease in the emissions of UFP precursors. The decrease of primary PM emissions and precursors of UFP also contributed to the reduction of urban and regional background sources., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.) more...

The Indo-Gangetic Plain (IGP) has high wintertime fine aerosol loadings that significantly modulate the widespread fog formation and sustenance. Here, we investigate the potential formation of secondary inorganic aerosol driven by excess ammonia during winter fog. Physicochemical properties of fine aerosols (PM 1 and PM 2.5 ) and trace gases (HCl, HONO, HNO 3 , SO 2 , and NH 3 ) were simultaneously monitored at hourly resolution using Monitor for AeRosols and Gases in Ambient air (MARGA-2S) for the first time in India. Results showed that four major ions, i.e., Cl - , NO 3 - , SO 4 2- , and NH 4 + contributed approximately 97% of the total measured inorganic ionic mass. The atmosphere was ammonia-rich in winter and ammonium was the dominant neutralizer with aerosol neutralization ratio (ANR) close to unity. The correlation between ammonium and chloride was ≥0.8, implying the significant formation of ammonium chloride during fog in Delhi. Thermodynamical model ISORROPIA-II showed the predicted PM 1 and PM 2.5 pH to be 4.49 ± 0.53, and 4.58 ± 0.48 respectively which were in good agreement with measurements. The ALWC increased from non-foggy to foggy periods and a considerable fraction of fine aerosol mass existed in the supermicron size range of 1-2.5 μm. The sulfur oxidation ratio (SOR) of PM 1 , PM 2.5 reached up to 0.60, 0.75 in dense fog and 0.74, 0.87 when ambient RH crossed a threshold of 95%, much higher than non-foggy periods (with confidence level of ≥95%) pointing to enhanced formation of secondary aerosol in fog., (Copyright © 2021 Elsevier Ltd. All rights reserved.) more...

Water soluble inorganic chemical ions of PM 1 and PM 2.5 and atmospheric trace gases were monitored simultaneously on hourly resolution at Indira Gandhi International Airport (IGIA), Delhi during 8 December 2017-10 February 2018. Monitoring was made by MARGA (Monitoring AeRosol and Gases in ambient Air) under winter fog experiment (WIFEX) program of the Ministry of Earth Sciences (MoES), Government of India. The result based on the analysis of the data so generated reveals that Cl - , NH 4 + , NO 3 - and SO 4 2- were dominant ions in order which collectively constituted 96.8 and 97.3% of the of the total measured ionic mass in PM 1 and PM 2.5 respectively. Their overall average concentrations in PM 1 were 19.5 ± 19.7, 18.4 ± 10.5, 16.6 ± 8.7 and 10.3 ± 5.7 μg/m 3 and in PM 2.5 were 36.0 ± 33.9, 32.7 ± 17.2, 28.5 ± 13.6 and 19.9 ± 13.9 μg/m 3 . Average concentrations of HCl, HNO 3 , HNO 2 , SO 2 and NH 3 trace gases were 0.7 ± 0.3, 2.7 ± 1.1, 6.6 ± 4.7, 22.0 ± 12.3 and 25.7 ± 9.1 μg/m 3 respectively. Weather parameters along with low mixing height played significant role in the occurrence of high concentration of these chemical species. NH 4 + was the prime neutralizer of the acidic components and mostly occurred in (NH 4 ) 2 SO 4 /NH 4 HSO 4 , NH 4 NO 3 and NH 4 Cl molecular forms. Major sources of these chemical species were fossil fuel combustion in aviation activity and transportation, coal burning in thermal power plants, industrial processes and emissions from biomass burning and agro-based activity. The quality of air with respect to PM 2.5 always remained deteriorated. It became alarming during low visibility period mainly due to high concentration of Cl - , NO 3 - , SO 4 2- and NH 4 + . Both meteorological and chemical processes interactively fed each other which occasionally resulted in fog development and visibility degradation. The knowledge gained by this study will help in simulation of atmospheric processes which lead to fog development and dispersal in the Delhi region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.) more...

Data on mass concentration of PM 2.5 and its carbonaceous and water soluble inorganic chemical ions were compiled through sampling of PM 2.5 at Indira Gandhi International Airport, Delhi during Dec. 16, 2015-Feb. 15, 2016 under Winter Fog Experiment (WIFEX) program of the Ministry of Earth Sciences (MoES) and analysing the samples. The data so generated were interpreted in terms of their variation on different time scales and apportioning their sources. It is found that mass concentration of PM 2.5 averaged over the whole period of observation was 198.6±55.6. The concentration of organic carbon (OC) and elemental carbon (EC) was 24.7±9.4 and 11.7±4.7μg/m 3 respectively with no any trend of increase or decrease over the observational period. SO 4 2- , Cl - and NO 3 - dominated over other anions with their overall average concentration 34.0±23.1, 32.7±16.1 and 13.3±8.7μg/m 3 respectively. Among cations, NH 4 + showed highest concentration with an average value of 21.0±10.6μg/m 3 . Variation of daily average mass concentration of these parameters over the period of observation matched well with the variation of PM 2.5 mass concentration indicating thereby to be the major contributors to the PM 2.5 mass. NH 4 + mostly occurred as NH 4 Cl and NH 4 NO 3 and poorly as (NH 4 ) 2 SO 4 or NH 4 HSO 4 . H + ion mostly occurred as H 2 SO 4 and occasionally as HNO 3 . Carbonaceous aerosols and NO 3 - were mainly generated from fossil-fuel combustion. NH 4 + and anthropogenic Cl - were mostly generated by biomass burning. The source of SO 4 2- was found to be industries and thermal power plants. Continental Ca 2+ and Mg 2+ originated from thermal power plants and soil dust., (Copyright © 2019. Published by Elsevier B.V.) more...