Background Environmental DNA (eDNA) is the DNA that can be extracted from an environmental sample, enabling the monitoring of whole biological communities across a large number of samples, at a ...potentially lower cost, which can significantly benefit river conservation. A systematic mapping protocol was designed to investigate the use of eDNA in rivers, specifically in terms of research topics, geographic and taxonomic biases, as well as information gaps. Furthermore, the potential research opportunities of eDNA in rivers and possible paths to find this kind of information on available platforms are identified. Methods A published systematic map protocol was applied, consisting of a search for published articles and gray literature in two bibliographic databases and one search engine. All search results were submitted to a 2-stage screening for relevance and pertinence in accordance with pre-defined eligibility criteria. Data extraction and codification regarding country of study, year, taxonomic group, sequencing platform, and type of technique employed resulted in a publicly available database. Results From 7372 studies initially obtained by the search, 545 met the inclusion criteria spanning a period from 2003 to 2022. The five countries with most studies are: USA (134), Japan (61), China (54), Brazil (29) and the UK (25). The most used fragments to analyze DNA are 16S and COI, whilst 26S and 23S are the least used. Only 84 (15%) of the studies reported hypervariable regions, among which the most used are V4 and V5. Regarding taxonomic groups, fishes are most often studied (176), followed by bacteria (138) and virus (52), while fungi is the least studied group (3). Concerning data availability, 229 (42%) studies provided access to sequencing data. Conclusions This study presents a comprehensive analysis of the available evidence regarding the implementation of the eDNA methods in rivers. The findings indicate that since the year 2003, this approach has been applied to aquatic lotic systems, and their recent increase can be attributed to the development of Next-Generation-Sequencing technologies and their reduced costs. However, there is a bias towards high-income countries, particularly USA and Europe. Widespread use and applications of this approach at a global level would allow for the generation of a large amount of information that can be compared between countries to understand if responses of aquatic systems follow similar patterns worldwide. Keywords: Lotic, Water, Metagenomics, Global trends, ROSES, NGS
After over 60 years, the powerful engines that accelerate ultra-high-energy cosmic rays (UHECRs) to the formidable energies at which we observe them from Earth remain mysterious. Assuming standard ...physics, we expect UHECR sources to lie within the local Universe (up to a few hundred Mpc). The distribution of matter in the local Universe is anisotropic, and we expect this anisotropy to be imprinted on the distribution of UHECR arrival directions. Even though intervening intergalactic and Galactic magnetic fields deflect charged UHECRs and can distort these anisotropies, some amount of information on the distribution of the sources is preserved. In this proceedings contribution, we present the results of the joint Pierre Auger Observatory and Telescope Array searches for (a) the largest-scale anisotropies (the harmonic dipole and quadrupole) and (b) correlations with a sample of nearby starburst galaxies and the 2MRS catalogue tracing stellar mass within 250 Mpc. This analysis updates our previous results with the most recent available data, notably with the addition of 3 years of new Telescope Array data. The main finding is a correlation between the arrival directions of 12.1%
−3.1%
+4.5%
of UHECRs detected with
E ≥
38 EeV by Auger or with
E ≳
49 EeV by TA and the positions of nearby starburst galaxies on a 15.1°
−3.0°
+4.6°
angular scale, with a 4.7σ post-trial significance, up from 4.2σ obtained in our previous study.
AbstractThe objectives of this work were first to evaluate the effect of coupling a zero-valent side filter to anaerobic fluidized bed bioreactors (HFBB) versus bioreactors without the zero-valent ...filter, also called methanogenic fluidized bed bioreactors (MFBB); and second to study the diversity of the microbial community in both types of bioreactors. At the end of operation (in the last 75 d), the HFBB reached a 95% removal of the incoming tetrachloroethylene, whereas the MFBBs without filter achieved a removal of 88%. Genera such as Dehalobacter spp., Desulfurospirillum spp., Desulfitobacterium spp., and Dehalococcoides spp., and Methanosarcina were found at the end of the treatment. Coupling zero-valent filters to bioreactors (HFBB) fed with high tetrachloroethylene concentration improved reactor performance high tetrachloroethylene removal and reduction of concentrations of vinyl chloride (VC) and dichlorethylene (DCE). This performance was consistent with significant higher concentrations of dehalogenating bacteria found in the HFBB.
The present work evaluated the effects of (i) feeding a water contaminated with 80 mg/L
PCE
to bioreactors seeded with inoculum not acclimated to
PCE
, (ii) coupling
ZVI
side filters to bioreactors, ...and (iii) working in different biological regimes, i.e., simultaneous methanogenic aeration and simultaneous methanogenic-denitrifying regimes, on fluidized bed bioreactor performance. Simultaneous electron acceptors refer to the simultaneous presence of two compounds operating as final electron acceptors in the biological respiratory chain (e.g., use of either O
2
or NO
3
−
in combination with a methanogenic environment) in a bioreactor or environmental niche. Four lab-scale, mesophilic, fluidized bed bioreactors (bioreactors) were implemented. Two bioreactors were operated as simultaneous methanogenic-denitrifying (
MD
) units, whereas the other two were operated in partially aerated methanogenic (
PAM
) mode. In the first period, all bioreactors received a wastewater with 1 g chemical oxygen demand of methanol per liter (
COD
-methanol/L). In a second period, all the bioreactors received the wastewater plus 80 mg perchloroethylene (
PCE
)/L; at the start of period 2, one
MD
and one
PAM
were coupled to side sand-zero valent iron filters (
ZVI
). All bioreactors were inoculated with a microbial consortium not acclimated to
PCE.
In this work, the performance of the full period 1 and the first 60 days of period 2 is reported and discussed. The
COD
removal efficiency and the nitrate removal efficiency of the bioreactors essentially did not change between period 1 and period 2, i.e., upon
PCE
addition. On the contrary, specific methanogenic activity in
PAM
bioreactors (both with and without coupled
ZVI
filter) significantly decreased. This was consistent with a sharp fall of methane productivity in those bioreactors in period 2. During period 2,
PCE
removals in the range 86 to 97 % were generally observed; the highest removal corresponded to
PAM
bioreactors along with the highest dehalogenation efficiency (94 %). Principal component analysis as well as cluster analysis confirmed the trends mentioned above, i.e., the better performance of
PAM
over
MD
, and the unexpected no effect of the
ZVI
side filters on
PCE
removal and dehalogenation efficiencies. To the best of our knowledge, this is the first report on the combined treatment
ZVI
-biological of a water polluted with
PCE
, where the biological operation relied on simultaneous electron acceptors.
The origin of ultra-high-energy cosmic rays (UHECRs) is still unknown. Their sources are believed to be within the local universe (a few hundred megaparsecs), but deflections by intergalactic and ...Galactic magnetic fields prevent us from straightforwardly associating UHECRs to their sources based on their arrival directions, making their angular distribution mostly isotropic. At higher energies, the number of potential source candidates and the magnetic deflections are both expected to be smaller, but so is the available amount of statistics. Hence, it is interesting to perform searches for anisotropies using several different energy thresholds. With a threshold of 8 EeV a dipole modulation has been discovered, and with higher thresholds evidence is mounting for correlations with certain nearby galaxies. Neither of the two main UHECR detectors, the Pierre Auger Observatory and the Telescope Array project, has full-sky coverage. Full-sky searches require combining the datasets of both, and a working group with members of both collaborations has been tasked with this. We present an overview of the challenges encountered in such analyses, recent results from the working group, possible ways of interpreting them, and an outlook for the near future.
Advances in environmental biotechnology and engineering 2018 Gortares-Maroyoqui, Pablo; Ulloa-Mercado, Ruth Gabriela; Ríos-Vázquez, Nidia Josefina ...
Environmental science and pollution research international,
08/2020, Letnik:
27, Številka:
23
Journal Article
Recenzirano
Odprti dostop
Optimal power in wind farms turns to be a modern problem for investors and decision makers; onshore wind farms are subject to performance and economic and environmental constraints. The aim of this ...work is to define the best installed capacity (best topology) with maximum performance and profits and consider environmental impacts as well. In this article, we continue the work recently done on wind farm topology-finding algorithm. The proposed resolution technique is based on finding the best topology of the system that maximizes the wind farm performance (availability) under the constraints of costs and capital investments. Global warming potential of wind farm is calculated and taken into account in the results. A case study is done using data and constraints similar to those collected from wind farm constructors, managers, and maintainers. Multi-state systems (MSS), universal generating function (UGF), wind, and load charge functions are applied. An economic study was conducted to assess the wind farm investment. Net present value (NPV) and levelized cost of energy (LCOE) were calculated for best topologies found.
Abstract
A search for time-directional coincidences of ultra-high-energy (UHE) photons above 10 EeV with gravitational wave (GW) events from the LIGO/Virgo runs O1 to O3 is conducted with the Pierre ...Auger Observatory. Due to the distinctive properties of photon interactions and to the background expected from hadronic showers, a subset of the most interesting GW events is selected based on their localization quality and distance. Time periods of 1000 s around and 1 day after the GW events are analyzed. No coincidences are observed. Upper limits on the UHE photon fluence from a GW event are derived that are typically at ∼7 MeV cm
−2
(time period 1000 s) and ∼35 MeV cm
−2
(time period 1 day). Due to the proximity of the binary neutron star merger GW170817, the energy of the source transferred into UHE photons above 40 EeV is constrained to be less than 20% of its total GW energy. These are the first limits on UHE photons from GW sources.
Abstract
A catalog containing details of the highest-energy cosmic rays recorded through the detection of extensive air showers at the Pierre Auger Observatory is presented with the aim of opening ...the data to detailed examination. Descriptions of the 100 showers created by the highest-energy particles recorded between 2004 January 1 and 2020 December 31 are given for cosmic rays that have energies in the range 78–166 EeV. Details are also given on a further nine very energetic events that have been used in the calibration procedure adopted to determine the energy of each primary. A sky plot of the arrival directions of the most energetic particles is shown. No interpretations of the data are offered.
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