scholarly journals Winter observations of CO<sub>2</sub> exchange between sea-ice and the atmosphere in a coastal fjord environment

2015 ◽  
Vol 9 (1) ◽  
pp. 45-75
Author(s):  
J. Sievers ◽  
L. L. Sørensen ◽  
T. Papakyriakou ◽  
M. K. Sejr ◽  
D. H. Søgaard ◽  
...  
Keyword(s):  
Sea Ice ◽  
Radiative Forcing ◽  
Heat Fluxes ◽  
Co2 Fluxes ◽  
Sequential Order ◽  
Strong Connection ◽  
North East ◽  
The Mean ◽  
Adsorption Desorption ◽  
First Time

Abstract. Eddy covariance observations of CO2-fluxes were conducted during March–April 2012 in a temporally sequential order at three locations on fast sea-ice and on newly formed polynya ice in a coastal fjord environment in North East Greenland. CO2 fluxes at the three sites, ICEI, POLYI and DNB, were found to increase over time in accordance with the progression of springtime warming: FCO2ICE1 =1.4 ± 4.9 mmol m−2 d−1, FCO2POLY1 =-3.4 ± 31.4 mmol m−2 d−1 and FCO2DNB =36.7 ± 72.8 mmol m−2 d−1, where values given are the mean and SD, and negative/positive values indicate uptake/outgassing respectively. Observations were carried out at the three sites for 8, 4 and 30 days respectively. A correlation analysis indicates a strong connection between net radiative forcing, wind-speed and CO2-fluxes. Correlations between latent heat fluxes and CO2-fluxes were found for the first time and support the presence of adsorption/desorption processes of CO2 in moist snow.

scholarly journals The Sub-Daily Variability of Aerosol Loading and Associated Radiative Forcing Over the Indian Region

2021 ◽  
Vol 9 ◽  
Author(s):  
T. Mukherjee ◽  
V. Vinoj
Keyword(s):  
Radiative Forcing ◽  
Spatial Scales ◽  
Indian Region ◽  
Large Spatial Scale ◽  
Aerosol Loading ◽  
Lower Amplitude ◽  
The Mean ◽  
Daily Variability ◽  
First Time ◽  
Modern Era

The sub-daily variability of aerosols affects the estimates of daily mean aerosol loading. However, large spatial scale estimates of their climate effects are mostly based on snapshots from low orbit satellites that may bias the mean estimate for daily, monthly, or annual timescales. In this study, an attempt is made to estimate the magnitude of such bias based on ground and satellite-based datasets. Using ground-based measurements, we show an apparent asymmetry (of the order of 10–50%) in the sub-daily variability of aerosol loading over the Indian region. For the first time, it is reported that this sub-daily variability has a spatial pattern with an increasing amplitude toward the east of the subcontinent. We also find this variability in aerosol loading is well-captured by the satellites but with a lower amplitude. Our study shows that such differences could alter the annual surface radiative forcing estimates by more than ∼15 W m−2 over this region. We find that NASA’s Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2), a state-of-the-art model-based chemical reanalysis, is unable to capture these sub-daily variabilities. This implies that both model and satellite-based radiative forcing estimates for large spatial scales should improve aerosol sub-daily information/variabilities for obtaining reliable radiative forcing estimates.

scholarly journals Dynamic and Thermodynamic Impacts of the Winter Arctic Oscillation on Summer Sea Ice Extent

2018 ◽  
Vol 31 (4) ◽  
pp. 1483-1497 ◽  
Author(s):  
Hyo-Seok Park ◽  
Andrew L. Stewart ◽  
Jun-Hyeok Son
Keyword(s):  
Sea Ice ◽  
Radiative Forcing ◽  
Arctic Oscillation ◽  
Reanalysis Data ◽  
Heat Fluxes ◽  
The Arctic ◽  
Ice Thickness ◽  
Sea Ice Extent ◽  
The Pacific ◽  
Basin Scale

Arctic summer sea ice extent exhibits substantial interannual variability, as is highlighted by the remarkable recovery in sea ice extent in 2013 following the record minimum in the summer of 2012. Here, the mechanism via which Arctic Oscillation (AO)-induced ice thickness changes impact summer sea ice is explored, using observations and reanalysis data. A positive AO weakens the basin-scale anticyclonic sea ice drift and decreases the winter ice thickness by 15 and 10 cm in the Eurasian and the Pacific sectors of the Arctic, respectively. Three reanalysis datasets show that the upward surface heat fluxes are reduced over wide areas of the Arctic, suppressing the ice growth during the positive AO winters. The winter dynamic and thermodynamic thinning preconditions the ice for enhanced radiative forcing via the ice–albedo feedback in late spring–summer, leading to an additional 10 cm of thinning over the Pacific sector of the Arctic. Because of these winter AO-induced dynamic and thermodynamics effects, the winter AO explains about 22% ( r = −0.48) of the interannual variance of September sea ice extent from 1980 to 2015.

YUKAGIR GEOGRAPHICAL TERMS IN TOPONYMY OF THE KOLYMA RIVER BASIN

2020 ◽  
Vol 9 (4(73)) ◽  
pp. 29-33
Author(s):  
N.S. Bagdaryyn
Keyword(s):  
River Basin ◽  
Semantic Analysis ◽  
Comparative Method ◽  
Linguistic Analysis ◽  
Word Formation ◽  
Morphological Features ◽  
North East ◽  
The North ◽  
First Time ◽  
Kolyma River

The article continues the author's research on the toponymy of the North-East of the Sakha Republic, in particular the Kolyma river basin, in the aspect of the interaction of related and unrelated languages. The relevance of this work is defined in the description of local geographical terminology of Yukagir origin, as a valuable and important material in the further study of toponymy of the region. For the first time, the toponymy of the Kolyma river basin becomes the object of sampling and linguistic analysis of toponyms with local geographical terms of Yukagir origin in order to identify and analyze them linguistically. The research was carried out by comparative method, word formation, structural, lexical and semantic analysis. As a result of the research, phonetic and morphological features are revealed, the formation of local geographical terms and geographical names of Yukagir origin is outlined, and previously unrecorded semantic shifts and dialectisms are revealed. The most active in the formation of terms and toponyms is the geographical term iилil / eҕal 'coast‘, which is justified by the representation of the Yukagirs’ coast' home, housing

RESULTS OF INTRALESIONAL TRIAMCINOLONE ACETONIDE FOR CHALAZION TREATMENT

2011 ◽  
pp. 100-104
Author(s):  
Thi Thu Nguyen ◽  
Viet Hien Vo ◽  
Thi Em Do
Keyword(s):  
Success Rate ◽  
Key Words ◽  
Triamcinolone Acetonide ◽  
Lower Eyelid ◽  
Upper Eyelid ◽  
Interventional Trial ◽  
The Mean ◽  
First Time

The study use intralesional triamcinolone acetonide injection proceduce for chalazion treatment.1. Objectives: To evaluate results of intralesional triamcinolone acetonide injection for chalazion treatment. 2. Method: This noncomparative prospective interventional trial included 72 chalazions of 61 patients. 3. Results: 61 patients (72 chalazions) with 19 males (31.1%) và 42 females (68.9%), the mean age was 24 ± 9,78 years. 31.1% patients was the first time chalazion and 68.9% patients was more than one times chalazion including 78.6% patients was recurrent at the first position and 21.4% patients occur at new position. 72 chalazions with 16 (22.2%) chalazions was treated before and 56 (77.8%) chalazions wasn’t done that. 72 chalazions with 49 chalazions (68.1%) are local in upper eyelid and 23 chalazions (31.9%) are local in lower eyelid. The mean of chalazion diameter is 6.99 ± 3.03mm. Intralesional triamcinolone acetonide is injected to treat 72 chalazions with 16 (22.2%) chalazions are injected through the route of skin and 56 (77.8%) chalazions are injected through the route of conjunctiva. After 2 weeks follow-up, the success rate was 93.1% and 6.9% failed. 4. Conclusion: intralesional triamcinolone acetonide injection for chalazion treatment is really effective. Key words: chalazion, intralesional triamcinolone acetonide.

Synthesis of a silymarin-gold nanoparticle conjugate and analysis of its liver-protecting activity

2021 ◽  
Vol 22 ◽  
Author(s):  
Sergey Staroverov ◽  
Sergey Kozlov ◽  
Alexander Fomin ◽  
Konstantib Gabalov ◽  
Alexey Volkov ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Liver Disease ◽  
Carbon Tetrachloride ◽  
Glutathione Depletion ◽  
Laboratory Animals ◽  
Experimental Hepatitis ◽  
Acute Liver Disease ◽  
The Mean ◽  
Extent Of Damage ◽  
First Time

Background: The liver disease problem prompts investigators to search for new methods of liver treatment. Introduction: Silymarin (Sil) protects the liver by reducing the concentration of free radicals and the extent of damage to the cell membranes. A particularly interesting method to increase the bioavailability of Sil is to use synthesized gold nanoparticles (AuNPs) as reagents. The study considered whether it was possible to use the silymarin-AuNP conjugate as a potential liver-protecting drug. Method: AuNPs were conjugated to Sil and examine the liver-protecting activity of the conjugate. Experimental hepatitis and hepatocyte cytolysis after carbon tetrachloride actionwere used as a model system, and the experiments were conducted on laboratory animals. Result: For the first time, silymarin was conjugated to colloidal gold nanoparticles (AuNPs). Electron microscopy showed that the resultant preparations were monodisperse and that the mean conjugate diameter was 18–30 nm ± 0.5 nm (mean diameter of the native nanoparticles, 15 ± 0.5 nm). In experimental hepatitis in mice, conjugate administration interfered with glutathione depletion in hepatocytes in response to carbon tetrachloride was conducive to an increase in energy metabolism, and stimulated the monocyte–macrophage function of the liver. The results were confirmed by the high respiratory activity of the hepatocytes in cell culture. Conclusion: We conclude that the silymarin-AuNP conjugate holds promise as a liver-protecting agent in acute liver disease caused by carbon tetrachloride poisoning.

scholarly journals Extraction and Mass Spectrometric Characterization of Terpenes Recovered from Olive Leaves Using a New Adsorbent-Assisted Supercritical CO2 Process

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1301
Author(s):  
Zully J. Suárez Montenegro ◽  
Gerardo Álvarez-Rivera ◽  
Jose A. Mendiola ◽  
Elena Ibáñez ◽  
Alejandro Cifuentes
Keyword(s):  
Aluminum Oxide ◽  
Silica Gel ◽  
Supercritical Co2 ◽  
Olive Leaves ◽  
Fractionation Process ◽  
Selective Enrichment ◽  
Adsorption Desorption ◽  
First Time ◽  
By Products

This work reports the use of GC-QTOF-MS to obtain a deep characterization of terpenoid compounds recovered from olive leaves, which is one of the largest by-products generated by the olive oil industry. This work includes an innovative supercritical CO2 fractionation process based on the online coupling of supercritical fluid extraction (SFE) and dynamic adsorption/desorption for the selective enrichment of terpenoids in the different olive leaves extracts. The selectivity of different commercial adsorbents such as silica gel, zeolite, and aluminum oxide was evaluated toward the different terpene families present in olive leaves. Operating at 30 MPa and 60 °C, an adsorbent-assisted fractionation was carried out every 20 min for a total time of 120 min. For the first time, GC-QTOF-MS allowed the identification of 40 terpenoids in olive leaves. The GC-QTOF-MS results indicate that silica gel is a suitable adsorbent to partially retain polyunsaturated C10 and C15 terpenes. In addition, aluminum oxide increases C20 recoveries, whereas crystalline zeolites favor C30 terpenes recoveries. The different healthy properties that have been described for terpenoids makes the current SFE-GC-QTOF-MS process especially interesting and suitable for their revalorization.

scholarly journals Neutrosophic ratio-type estimators for estimating the population mean

2021 ◽  
Author(s):  
Zaigham Tahir ◽  
Hina Khan ◽  
Muhammad Aslam ◽  
Javid Shabbir ◽  
Yasar Mahmood ◽  
...  
Keyword(s):  
Minimum Mean Square Error ◽  
Auxiliary Information ◽  
Population Parameter ◽  
Uncertain Information ◽  
Population Mean ◽  
Classical Statistics ◽  
Neutrosophic Statistics ◽  
The Mean ◽  
Type Data ◽  
First Time

AbstractAll researches, under classical statistics, are based on determinate, crisp data to estimate the mean of the population when auxiliary information is available. Such estimates often are biased. The goal is to find the best estimates for the unknown value of the population mean with minimum mean square error (MSE). The neutrosophic statistics, generalization of classical statistics tackles vague, indeterminate, uncertain information. Thus, for the first time under neutrosophic statistics, to overcome the issues of estimation of the population mean of neutrosophic data, we have developed the neutrosophic ratio-type estimators for estimating the mean of the finite population utilizing auxiliary information. The neutrosophic observation is of the form $${Z}_{N}={Z}_{L}+{Z}_{U}{I}_{N}\, {\rm where}\, {I}_{N}\in \left[{I}_{L}, {I}_{U}\right], {Z}_{N}\in [{Z}_{l}, {Z}_{u}]$$ Z N = Z L + Z U I N where I N ∈ I L , I U , Z N ∈ [ Z l , Z u ] . The proposed estimators are very helpful to compute results when dealing with ambiguous, vague, and neutrosophic-type data. The results of these estimators are not single-valued but provide an interval form in which our population parameter may have more chance to lie. It increases the efficiency of the estimators, since we have an estimated interval that contains the unknown value of the population mean provided a minimum MSE. The efficiency of the proposed neutrosophic ratio-type estimators is also discussed using neutrosophic data of temperature and also by using simulation. A comparison is also conducted to illustrate the usefulness of Neutrosophic Ratio-type estimators over the classical estimators.

scholarly journals P1398 Echocardiographic continuous monitoring of exercise stress test using probe fixation device

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
K Wdowiak-Okrojek ◽  
P Wejner-Mik ◽  
Z Bednarkiewicz ◽  
P Lipiec ◽  
J D Kasprzak
Keyword(s):  
Image Quality ◽  
Physical Exercise ◽  
Stress Test ◽  
Exercise Stress Test ◽  
Bicycle Ergometer ◽  
Exercise Stress ◽  
Fixation Device ◽  
The Mean ◽  
First Time

Abstract Background Stress echocardiography (SE) plays an important role among methods of noninvasive diagnosis of ischemic disease. Despite the advantages of physical exercise as the most physiologic stressor, it is difficult (bicycle ergometer) or impossible (treadmill) to obtain and maintain the acoustic window during the exercise. Recently, an innovative probe fixation device was introduced and a research plan was developed to assess the feasibility of external probe fixation during exercise echocardiography on a supine bicycle and upright treadmill exercise for the first time. Methods 37 subjects (36 men, mean age 39 ± 16 years, 21 healthy volunteers, 16 patients with suspected coronary artery disease) were included in this study. This preliminary testing stage included mostly men due to more problematic probe fixation in women. All subjects underwent a submaximal exercise stress test on a treadmill (17/37) or bicycle ergometer (11/37). Both sector and matrix probes were used. We assessed semi-quantitatively the quality of acquired apical views at each stage – the four-point grading system was used (0-no view, 1-suboptimal quality, 2-optimal quality, 3-very good quality), 2-3 sufficient for diagnosis. Results The mean time required for careful positioning of the probe and image optimization was 12 ± 3 min and shortened from 13,7 to 11,1 minutes (mean) in first vs second half of the cohort documenting learning curve. At baseline, 9 patients had at least one apical view of quality precluding reliable analysis. Those patients were excluded from further assessment. During stress, 17 patients maintained the optimal or very good quality of all apical views, whereas in 11 patients the quality significantly decreased during the stress test and required probe repositioning. The mean image quality score at baseline was 2,61 ± 0,48 and 2,25 ± 0,6 after exercise. Expectedly, good image quality was easier to obtain and maintain in the supine position (score 2,74 ± 0,44) points as compared with upright position (score 2,25 ± 0,57). Conclusion This preliminary, unique experience with external probe fixation device indicates that continuous acquisition and monitoring of echocardiographic images is feasible during physical exercise, and for the first time ever - also on the treadmill. This feasibility data stem from almost exclusively male patients and the estimated rate of sufficient image quality throughout the entire test is currently around 60%. We are hoping, that gaining more experience with the product could increase the success rate on exercise tests. Abstract P1398 Figure. Treadmill and ergometer stress test

scholarly journals Decadal increase in Arctic dimethylsulfide emission

2019 ◽  
Vol 116 (39) ◽  
pp. 19311-19317 ◽  
Author(s):  
Martí Galí ◽  
Emmanuel Devred ◽  
Marcel Babin ◽  
Maurice Levasseur
Keyword(s):  
Sea Ice ◽  
Radiative Forcing ◽  
Positive Trend ◽  
Aerosol Formation ◽  
Atmospheric Measurements ◽  
Sea Ice Extent ◽  
Phytoplankton Productivity ◽  
Physical Forcing ◽  
Ice Retreat ◽  
Aerosol Cloud Interactions

Dimethylsulfide (DMS), a gas produced by marine microbial food webs, promotes aerosol formation in pristine atmospheres, altering cloud radiative forcing and precipitation. Recent studies suggest that DMS controls aerosol formation in the summertime Arctic atmosphere and call for an assessment of pan-Arctic DMS emission (EDMS) in a context of dramatic ecosystem changes. Using a remote sensing algorithm, we show that summertime EDMS from ice-free waters increased at a mean rate of 13.3 ± 6.7 Gg S decade−1 (∼33% decade−1) north of 70°N between 1998 and 2016. This trend, mostly explained by the reduction in sea-ice extent, is consistent with independent atmospheric measurements showing an increasing trend of methane sulfonic acid, a DMS oxidation product. Extrapolation to an ice-free Arctic summer could imply a 2.4-fold (±1.2) increase in EDMS compared to present emission. However, unexpected regime shifts in Arctic geo- and ecosystems could result in future EDMS departure from the predicted range. Superimposed on the positive trend, EDMS shows substantial interannual changes and nonmonotonic multiyear trends, reflecting the interplay between physical forcing, ice retreat patterns, and phytoplankton productivity. Our results provide key constraints to determine whether increasing marine sulfur emissions, and resulting aerosol–cloud interactions, will moderate or accelerate Arctic warming in the context of sea-ice retreat and increasing low-level cloud cover.

scholarly journals On tho proportions of the prevailing winds, the mean temperature, and depth of rain in the climate of London, computed through a cycle of Eighteen Years, or periods of the Moon’s declination

1843 ◽  
Vol 4 ◽  
pp. 300-300
Keyword(s):  
The Moon ◽  
Fair Weather ◽  
North West ◽  
West Wind ◽  
North East ◽  
East Wind ◽  
The North ◽  
The Common ◽  
The Mean ◽  
Solar Influence

In this paper the author investigates the periodical variations of the winds, rain and temperature, corresponding to the conditions of the moon’s declination, in a manner similar to that he has already followed in the case of the barometrical variations, on a period of years extending from 1815 to 1832 inclusive. In each case he gives tables of the average quantities for each week, at the middle of which the moon is in the equator, or else has either attained its maximum north or south declination. He thus finds that a north-east wind is most promoted by the constant solar influence which causes it, when the moon is about the equator, going from north to south; that a south-east wind, in like manner, prevails most when the moon is proceeding to acquire a southern declination ; that winds from the south and west blow more when the moon is in her mean degrees of declination, going either way, than with a full north or south declination ; and that a north-west wind, the common summer and fair weather wind of the climate, affects, in like manner, the mean declination, in either direction, in preference to the north or south, and most when the moon is coming north. He finds the average annual depth of rain, falling in the neighbourhood of London, is 25’17 inches.

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