scholarly journals Increased Likelihood of High Nitrous Oxide (N2O) Exchange in Soils at Reduced Microbial Diversity

2021 ◽  
Vol 13 (4) ◽  
pp. 1685
Author(s):  
Søren Christensen ◽  
Wilhelmina H. Gera Hol ◽  
Viola Kurm ◽  
Mette Vestergård
Keyword(s):  
Microbial Growth ◽  
Oxygen Depletion ◽  
Trace Gas ◽  
Turnover Rates ◽  
Soil Organisms ◽  
Future Studies ◽  
Microbial Regrowth ◽  
Local Oxygen ◽  
Soil Dilution ◽  
Very High

Rare soil organisms are normally considered of less importance for ecosystem functioning. We present results that oppose this view. In otherwise well-aerated soils, anaerobic/microaerophilic production or consumption of the trace gas N2O occurs in small soil volumes, when intense decomposition activity at the site leads to local oxygen depletion. At such patch scales, the control of microbial growth and oxygen consumption may depend on the specific organisms present. We assessed N2O turnover in an experiment, where soil dilution from 10−2 over 10−4 to 10−6 followed by microbial regrowth resulted in similar microbial biomass and respiration but reduced diversity. We found an increasing number of very high N2O turnover rates when soil dilution increased from 10−2 over 10−4 to 10−6, as revealed from a significantly increased skewness of the frequency distribution of N2O turnover levels. N2O turnover also tended to increase (p = 0.08) by 20–30% when soil was diluted from 10−2 to 10−6. This suggests that rare soil organisms regulate the local activity of fast-growing microorganisms and thus reduce the probability that anoxic/microaerophilic soil volumes develop. Future studies may reveal which less abundant organisms prevent development of anoxic/microaerophilic conditions in well-aerated soils.

scholarly journals The high Arctic in extreme winters: vortex, temperature, and MLS and ACE-FTS trace gas evolution

2008 ◽  
Vol 8 (3) ◽  
pp. 505-522 ◽  
Author(s):  
G. L. Manney ◽  
W. H. Daffer ◽  
K. B. Strawbridge ◽  
K. A. Walker ◽  
C. D. Boone ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Lower Stratosphere ◽  
High Arctic ◽  
Trace Gas ◽  
Satellite Measurements ◽  
Broadband Emission ◽  
Gas Measurements ◽  
Chemistry Experiment ◽  
Very High ◽  
Good Agreement

Abstract. The first three Arctic winters of the ACE mission represented two extremes of winter variability: Stratospheric sudden warmings (SSWs) in 2004 and 2006 were among the strongest, most prolonged on record; 2005 was a record cold winter. Canadian Arctic Atmospheric Chemistry Experiment (ACE) Validation Campaigns were conducted at Eureka (80° N, 86° W) during each of these winters. New satellite measurements from ACE-Fourier Transform Spectrometer (ACE-FTS), Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), and Aura Microwave Limb Sounder (MLS), along with meteorological analyses and Eureka lidar temperatures, are used to detail the meteorology in these winters, to demonstrate its influence on transport, and to provide a context for interpretation of ACE-FTS and validation campaign observations. During the 2004 and 2006 SSWs, the vortex broke down throughout the stratosphere, reformed quickly in the upper stratosphere, and remained weak in the middle and lower stratosphere. The stratopause reformed at very high altitude, near 75 km. ACE measurements covered both vortex and extra-vortex conditions in each winter, except in late-February through mid-March 2004 and 2006, when the strong, pole-centered vortex that reformed after the SSWs resulted in ACE sampling only inside the vortex in the middle through upper stratosphere. The 2004 and 2006 Eureka campaigns were during the recovery from the SSWs, with the redeveloping vortex over Eureka. 2005 was the coldest winter on record in the lower stratosphere, but with an early final warming in mid-March. The vortex was over Eureka at the start of the 2005 campaign, but moved away as it broke up. Disparate temperature profile structure and vortex evolution resulted in much lower (higher) temperatures in the upper (lower) stratosphere in 2004 and 2006 than in 2005. Satellite temperatures agree well with lidar data up to 50–60 km, and ACE-FTS, MLS and SABER show good agreement in high-latitude temperatures throughout the winters. Consistent with a strong, cold upper stratospheric vortex and enhanced radiative cooling after the SSWs, MLS and ACE-FTS trace gas measurements show strongly enhanced descent in the upper stratospheric vortex in late January through March 2006 compared to that in 2005.

scholarly journals MEASURING THE ENVIRONMENTAL PERFORMANCE OF COUNTRIES BY CODAS AND TOPSIS METHODS: G7 GROUP COUNTRIES EXAMPLE

2021 ◽  
Vol 9 (59) ◽  
Keyword(s):  
Environmental Protection ◽  
Performance Index ◽  
Environmental Performance ◽  
Topsis Method ◽  
Data Set ◽  
Future Studies ◽  
Environmental Performance Index ◽  
Two Factors ◽  
The Usa ◽  
Very High

With the awareness of their environmental performance, countries can provide strategies and policies to improve their environmental performance. Thus, countries can contribute to their own economic development by increasing their environmental performance. Therefore, measuring the environmental performance of countries is of great importance. Environmental performance of countries can be measured by the Environmental Performance Index (EPI). EPI consists of two factors, environmental health and ecosystem vitality. Its factors are environmental protection components, and environmental protection components are environmental protection variables. In this context, the research has two purposes. The first of these,To measure the latest and up-to-date environmental performances of the G7 group countries for 2018, using CODAS and TOPSIS multi-criteria decision-making methods (MCDM) over the values of EPI components. The second is to determine which MCDM method can be used to explain the EPI values of countries the most. According to the findings, the ranking of countries' environmental performance with the CODAS method was determined as England, France, Japan, Germany, Canada, Italy and the USA. According to the TOPSIS method, this ranking was determined as England, France, Germany, Japan, Canada, Italy and the USA. According to another finding, it has been observed that there is a significant, positive and very high relationship between the EPI values of the countries and the values measured by the CODAS and TOPSIS methods. According to this result, it was evaluated that EPI can be explained by both methods. In addition, it has been concluded that the correlation value between TOPSIS values of EPI within the scope of the research is higher than the CODAS method, so it can be explained better with the TOPSIS method compared to the EPI CODAS method. In the literature, in order not to find a study measuring the environmental performance of countries with CODAS and TOPSIS methods, it was evaluated that the study in question contributed to the literature, since the findings obtained as a result of the research became a data set for future studies. Keywords: Environmental Performance, Environmental Performance Index, CODAS, TOPSIS

Ouabain binding kinetics and FXYD7 expression in astrocytes and neurons in primary cultures: implications for cellular contributions to extracellular K+ homeostasis?

2010 ◽  
Vol 6 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Liang Peng ◽  
Rong Huang ◽  
Shiquen Zhang ◽  
Leif Hertz
Keyword(s):  
Primary Cultures ◽  
Granule Neurons ◽  
Turnover Rates ◽  
Ouabain Binding ◽  
Neuronal Excitation ◽  
Cellular Expression ◽  
Uptake Rates ◽  
The Brain ◽  
Very High

Although Na+,K+-ATPase-mediated K+ uptake into astrocytes plays a major role in re-establishing resting extracellular K+ following neuronal excitation little information is available about astrocytic Na+,K+-ATPase function, let alone mechanisms returning K+ to neurons. The catalytic units of the Na+,K+-ATPase are the astrocyte-specific α2, the neuron-specific α3 and the ubiquitously expressed α1. In the present work, Bmax and KD values for α1, α2 and α3 subunits were computed in cultured cerebro-cortical mouse astrocytes and cerebellar granule neurons by non-linear regression as high-affinity (α2, α3) and low-affinity (α1) [3H]ouabain binding sites, which stoichiometrically equal transporter sites. Cellular expression was also determined of the brain- and α1-β1 isoform-specific FDYX7, regulating Na+,K+-ATPase efficiency and K+-sensitivity. From ouabain-sensitive K+ uptake rates published by ourselves (Walz and Hertz, 1982) or others (Atterwill et al., 1985), Na+,K+-ATPase turnover was determined. Subunits α2 and α3 showed Bmax of 15–30 pmol/mg protein, with maximum turnover rates of 70–80/s. Bmax of the α1 subunit was low in neurons but very high in astrocytes (645 pmol/mg protein), where turnover rate was slow, reflecting expression of selectively expressed FXYD7, and binding was increased by K+. The role of these characteristics for K+ homeostasis are discussed.

scholarly journals Identifying Scientific and Technical “Unicorns”

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Lucy L. Xu ◽  
Miao Qi ◽  
Fred Y. Ye
Keyword(s):  
Linear Model ◽  
Design Methodology ◽  
Science And Technology ◽  
High Impact ◽  
Future Studies ◽  
Scientific Papers ◽  
Practical Implications ◽  
Very High ◽  
Quantitative Consideration

AbstractPurposeUsing the metaphor of “unicorn,” we identify the scientific papers and technical patents characterized by the informetric feature of very high citations in the first ten years after publishing, which may provide a new pattern to understand very high impact works in science and technology.Design/methodology/approachWhen we set CT as the total citations of papers or patents in the first ten years after publication, with CT≥ 5,000 for scientific “unicorn” and CT≥ 500 for technical “unicorn,” we have an absolute standard for identifying scientific and technical “unicorn” publications.FindingsWe identify 165 scientific “unicorns” in 14,301,875 WoS papers and 224 technical “unicorns” in 13,728,950 DII patents during 2001–2012. About 50% of “unicorns” belong to biomedicine, in which selected cases are individually discussed. The rare “unicorns” increase following linear model, the fitting data show 95% confidence with the RMSE of scientific “unicorn” is 0.2127 while the RMSE of technical “unicorn” is 0.0923.Research limitationsA “unicorn” is a pure quantitative consideration without concerning its quality, and “potential unicorns” as CT≤5,000 for papers and CT≤500 for patents are left in future studies.Practical implicationsScientific and technical “unicorns” provide a new pattern to understand high-impact works in science and technology. The “unicorn” pattern supplies a concise approach to identify very high-impact scientific papers and technical patents.Originality/valueThe “unicorn” pattern supplies a concise approach to identify very high impact scientific papers and technical patents.

scholarly journals Detection dogs as a help in the detection of COVID-19 Can the dog alert on COVID-19 positive persons by sniffing axillary sweat samples ? Proof-of-concept study

2020 ◽  
Author(s):  
Dominique Grandjean ◽  
Riad Sarkis ◽  
Jean-Pierre Tourtier ◽  
Clothilde Julien-Lecocq ◽  
Aymeric Benard ◽  
...  
Keyword(s):  
Colon Cancer ◽  
Cancer Detection ◽  
Positive Sample ◽  
The Other ◽  
Explosive Detection ◽  
Proof Of Concept ◽  
Future Studies ◽  
Concept Study ◽  
Axillary Sweat ◽  
Very High

AbstractThe aim of this study is to evaluate if the sweat produced by COVID-19 persons (SARS-CoV-2 PCR positive) has a different odour for trained detection dogs than the sweat produced by non COVID-19 persons. The study was conducted on 3 sites, following the same protocol procedures, and involved a total of 18 dogs. A total of 198 armpits sweat samples were obtained from different hospitals. For each involved dog, the acquisition of the specific odour of COVID-19 sweat samples required from one to four hours, with an amount of positive samples sniffing ranging from four to ten. For this proof of concept, we kept 8 dogs of the initial group (explosive detection dogs and colon cancer detection dogs), who performed a total of 368 trials, and will include the other dogs in our future studies as their adaptation to samples scenting takes more time.The percentages of success of the dogs to find the positive sample in a line containing several other negative samples or mocks (2 to 6) were 100p100 for 4 dogs, and respectively 83p100, 84p100, 90p100 and 94p100 for the others, all significantly different from the percentage of success that would be obtained by chance alone.We conclude that there is a very high evidence that the armpits sweat odour of COVID-19+ persons is different, and that dogs can detect a person infected by the SARS-CoV-2 virus.

scholarly journals Harnessing the Power of Metabarcoding in the Ecological Interpretation of Plant—Pollinator DNA Data: Strategies and Consequences of Filtering Approaches

Diversity ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 437
Author(s):  
Nicola Tommasi ◽  
Andrea Ferrari ◽  
Massimo Labra ◽  
Andrea Galimberti ◽  
Paolo Biella
Keyword(s):  
Species Richness ◽  
High Sensitivity ◽  
Conservative Approach ◽  
Pollen Assemblage ◽  
Future Studies ◽  
Molecular Features ◽  
Dna Metabarcoding ◽  
Plant Pollinator ◽  
Very High ◽  
Do So

Although DNA metabarcoding of pollen mixtures has been increasingly used in the field of pollination biology, methodological and interpretation issues arise due to its high sensitivity. Filtering or maintaining false positives, contaminants, and rare taxa or molecular features could lead to different ecological results. Here, we reviewed how this choice has been addressed in 43 studies featuring pollen DNA metabarcoding, which highlighted a very high heterogeneity of filtering methods. We assessed how these strategies shaped pollen assemblage composition, species richness, and interaction networks. To do so, we compared four processing methods: unfiltering, filtering with a proportional 1% of sample reads, a fixed threshold of 100 reads, and the ROC approach (Receiver Operator Characteristic). The results indicated that filtering impacted species composition and reduced species richness, with ROC emerging as a conservative approach. Moreover, in contrast to unfiltered networks, filtering decreased network Connectance and Entropy, and it increased Modularity and Connectivity, indicating that using cut-off thresholds better describes interactions. Overall, unfiltering might compromise reliable ecological interpretations, unless a study targets rare species. We discuss the suitability of each filtering type,plead for justifying filtering strategies on biological or methodological bases and for developing shared approaches to make future studies more comparable.

Two Methods for Correcting Range-Dependent Limitations of Lightning Mapping Arrays

2018 ◽  
Vol 35 (6) ◽  
pp. 1273-1282 ◽  
Author(s):  
Stephanie A. Weiss ◽  
Donald R. MacGorman ◽  
Eric C. Bruning ◽  
Vanna C. Chmielewski
Keyword(s):  
Detection Efficiency ◽  
Sorting Algorithm ◽  
Source Detection ◽  
Very High Frequency ◽  
Future Studies ◽  
Large Sets ◽  
Source Data ◽  
Using Data ◽  
Mapping Arrays ◽  
Very High

AbstractLightning Mapping Arrays (LMAs) detect very high frequency (VHF) radiation produced by lightning as it propagates; however, VHF source detection efficiency drops off rapidly with range from the centers of the arrays, which results in a maximum of source points over the center of the network for large datasets. Using data from nearly one billion detected sources of various powers, an approximation of VHF source detection efficiency (relative to the number of sources detected within 25 km of the center of the array) for the Oklahoma LMA is calculated for different ranges and source powers. The calculated source detection efficiencies are then used to normalize the VHF source data out to a range of 125 km, as a method for correcting the detection efficiency drop-off with range. The data are also sorted into flashes using a popular flash-sorting algorithm in order to compare how well flash sorting corrects for detection efficiency drop-off with range compared to the normalization method. Both methods produce similar patterns and maxima of the lightning location, but the differences between them are identified and highlighted. The use of a flash-sorting algorithm is recommended for future studies involving large sets of data.

Abstract 156: Capnographic Differences in Out-of-hospital Overdose-related, Respiratory, and Cardiac Arrests

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_4) ◽  
Author(s):  
Robyn McDannold ◽  
Chengcheng Hu ◽  
Daniel W Spaite ◽  
Annemarie E Silver ◽  
Margaret Mullins ◽  
...  
Keyword(s):  
Blood Flow ◽  
Continuous Variables ◽  
Exact Test ◽  
Future Studies ◽  
First Report ◽  
Chi Squared ◽  
Co2 Level ◽  
The Mean ◽  
Full Waveforms ◽  
Very High

Background: Little is known about the ventilatory aspects of overdose-related OHCA (OD-OHCA). We compared maximum ETCO2 (mETCO2; each patient’s highest CO2 level) and mean for each recorded minute of CPR in OD-OHCA to that of respiratory (R-OHCA) and cardiac (C-OHCA) arrests. Methods: Continuous CO2 data (Zoll E/X series monitors) were obtained from 3 Arizona EMS agencies. Cases had at least 3 min of recorded CO2 during CPR. Arrests were classified as OD-OHCA by EMS and/or hospital documentation. Any drug OD was included (e.g., opioids, mixed). C-OHCA and R-OHCA cases were randomly chosen for comparison. The groups were compared using Fisher’s exact test or Chi-squared for categorical and Kruskal-Wallis for continuous variables. Results: Included were 263 subjects (37 OD-OHCA, 157 C-OHCA and 69 R-OHCA; median age 61, 64% male, 1/10-12/18) with 10,271 min of data [median resuscitation interval 37 min (IQR 29, 47)]. Mean ETCO2 (SD): OD-OHCA [41 mmHg (24)]; R-OHCA [40 (23)], C-OHCA [30 (13); p<0.01]. Median mETCO2: OD-OHCA [57 mmHg (95CI: 50, 77)]; R-OHCA [61 (50, 73)], C-OHCA [48 (44, 50); p<0.001; Fig 1]. While mean ETCO2 and mETCO2 were similar for OD-OHCA and R-OHCA, they were both significantly higher than C-OHCA (p<0.01 for all comparisons). ETCO2 waveforms in OD-OHCA resembled the very high, full waveforms typical of R-OHCA while those in C-OHCA tended to be low and blunted. Conclusions: We believe this is the first report of continuous capnography during resuscitation of OD-OHCA. The mean ETCO2 and median of mETCO2 of OD-OHCA and R-OHCA imply similar physiology (hypoventilation and hypercapnia leading to arrest). Both etiologies had much higher ETCO2 values compared to C-OHCA, where low blood flow delivers minimal CO2 to the lungs and yields low, and morphologically different, waveforms. Future studies assessing OD arrest physiology and various approaches to resuscitation and pharmacological reversal are needed.

Remarks on the birds of Mt Kinabalu

1964 ◽  
Vol 161 (982) ◽  
pp. 80-90 ◽  
Keyword(s):  
Contour Line ◽  
High Mountain ◽  
Great Work ◽  
The West ◽  
West Pacific ◽  
Future Studies ◽  
Very High

Mr Smythies has very ably brought together what is known about Kinabalu and related high mountain bird faunas. But there remains much that is unclear in this peculiar problem. As I have spent some time near the extreme summit of Kinabalu itself—and all the bird food data mentioned by Mr Smythies for that zone derive from the stomach analyses which I made during one February—and a total of several years above the ‘montane fauna contour line’ further south in the Sarawak and Kalimantan mountains and uplands, I venture to add a few points with a view to future studies. It seems important to be clear that the birds here listed by Smythies are those mainly peculiar to Borneo high levels and all ones not once recorded off the mountains. But there are an appreciable (and significant) further series which all previous authors have considered ‘montane’ (e.g. Banks (1949), and Smythies’s own great work (1960)). Thus when he uses the term characteristic for the 5000 ft. zone and upwards, he means ‘peculiar to'. For instance at the very highest ‘heath scrub’ levels of Kinabalu there are two very common montane birds which he does not mention— because no doubt they have also been recorded at much lower altitudes. In my view they cannot therefore be omitted from top-level consideration. For by that standard the top-level Blackbird should equally be excluded—as common in the lowlands throughout the West Pacific. Indeed, a capacity to be both very high, fully ‘alpine’ and submontane or lowland may provide significant new insight.

Sign in / Sign up

Export Citation Format

Share Document