scholarly journals ROLE OF THE TROPOPAUSE IN STRATOSPHERIC--TROPOSPHERIC EXCHANGE PROCESSES. Atmospheric Science Paper No. 107.

1967 ◽  
Author(s):  
E.R. Reiter ◽  
M.E. Glasser ◽  
J.D. Mahlman
Keyword(s):  
Atmospheric Science ◽  
Exchange Processes ◽  
Science Paper

scholarly journals June Bacon-Bercey: Pioneering Meteorologist and Passionate Supporter of Science

Eos ◽  
2020 ◽  
Vol 101 ◽  
Author(s):  
Katherine Kornei
Keyword(s):  
African Americans ◽  
Atmospheric Science

Bacon-Bercey redefined the role of the television meteorologist, blazing trails for African Americans and endowing an AGU scholarship for women studying atmospheric science.

scholarly journals Fluctuation Theorem of Information Exchange between Subsystems that Co-Evolve in Time

Symmetry ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 433 ◽  
Author(s):  
Lee Jinwoo
Keyword(s):  
Information Exchange ◽  
Degrees Of Freedom ◽  
Fluctuation Theorem ◽  
Equilibrium System ◽  
Dynamic Coupling ◽  
Stochastic Thermodynamics ◽  
Exchange Processes ◽  
Exchange Information ◽  
Non Equilibrium

Sagawa and Ueda established a fluctuation theorem of information exchange by revealing the role of correlations in stochastic thermodynamics and unified the non-equilibrium thermodynamics of measurement and feedback control. They considered a process where a non-equilibrium system exchanges information with other degrees of freedom such as an observer or a feedback controller. They proved the fluctuation theorem of information exchange under the assumption that the state of the other degrees of freedom that exchange information with the system does not change over time while the states of the system evolve in time. Here we relax this constraint and prove that the same form of the fluctuation theorem holds even if both subsystems co-evolve during information exchange processes. This result may extend the applicability of the fluctuation theorem of information exchange to a broader class of non-equilibrium processes, such as a dynamic coupling in biological systems, where subsystems that exchange information interact with each other.

Transforming Public-Private Networks An XBRL-Based Infrastructure for Transforming Business-to-Government Information Exchange

2011 ◽  
Vol 7 (4) ◽  
pp. 35-45 ◽  
Author(s):  
Niels de Winne ◽  
Marijn Janssen ◽  
Nitesh Bharosa ◽  
Remco van Wijk ◽  
Joris Hulstijn
Keyword(s):  
Information Exchange ◽  
Government Information ◽  
Public Agencies ◽  
Public And Private ◽  
Exchange Processes ◽  
Efficiency And Effectiveness ◽  
One Stop ◽  
Changes Over Time

Companies are required by law to report all kinds of information to various public agencies. Since most public agencies are autonomous and define their information demands independent of each other, companies have to report information to various agencies in different ways. Accordingly, governments are initiating programs that aim to transform business-to government information exchange to reduce the administrative burden for companies and improve the accountability at the same time. Yet little research is available on the type of transformations needed and the role of the infrastructure. Drawing on a case study, this paper investigates the interplay between technical infrastructure and transformation. In this case study an information brokerage infrastructure based on the Extensible Business Reporting Language (XBRL) was developed providing a one stop shop for companies and public agencies. The case study shows that the infrastructure should be flexible enough to accommodate changes over time but stable enough to attract a large user-base. The increase in efficiency and effectiveness of information exchange processes requires extensive transformation from both public and private parties.

THE ROLE OF ESTRADIOL IN THE SUSTENTATION OF FETOPLACENTAL SYSTEM

2016 ◽  
Vol 1 (61) ◽  
pp. 75-79
Author(s):  
Андриевская ◽  
Irina Andrievskaya ◽  
Луценко ◽  
Mikhail Lutsenko ◽  
Довжикова ◽  
...  
Keyword(s):  
The State ◽  
Cmv Infection ◽  
Histochemical Reaction ◽  
Third Trimester ◽  
Paraffin Sections ◽  
Igg Antibody ◽  
The Third ◽  
Exchange Processes ◽  
Hormonal Dysfunction

The aim of the study is to define the role of abnormalities in the formation of estriol hormones in the development of hormonal dysfunction of fetoplacental system. There were examined 39 placentas from women with exacerbation of chronic cytomegalovirus infection at the third trimester of pregnancy and IgG antibody titer 1:1600 and 30 placentas from women with latent CMV infection and titer 1:400. The activity of androstenedione dehydrogenase was found out with histochemical method on cryostat sections of freshly frozen tissues of placentas by Lloyd’s method. The assessment of intensiveness of histochemical reaction was done with cytophotometric method by Scion program. Estradiol in homogenate of placenta was measured with immune-enzyme method. The quantity of nuclei of placenta syncytiotrophoblast in the state of apoptosis was done with cytophotometric method on paraffin sections stained by ISEL method. By the results of the study the exacerbation of CMV infection at the third trimester of pregnancy leads to the decrease of intensiveness of histochemical reaction in placentas to androstenedione dehydrogenase till 32.1±2.88 pixel/mcm2 (at the latent course it is 54.2±4.31 pixel/mcm2, р<0.001), and in homogenate of placenta to the decrease of estradiol till 18443.2±117.53 pmole/l (at the latent course of the disease it is 28977.7±158.13 pmole/l, p<0.001), on paraffin sections in syncytiotrophoblast by the increase of nuclei number in the state of apoptosis till 5.0±0.03% (at latent course of the disease it is 1.2±0.001%, р<0.001) and vacuole formation, which leads to destructive damages of syncytiotrophoblast cytoplasm. The obtained results prove that the exacerbation of CMV infection at the third trimester of pregnancy causes the decrease of estriol hormones formation, which is accompanied by the damage of morphostructure and exchange processes in cell elements of placenta.

Water - Compacted Na-Bentonite Interaction in Simulated Nuclear Fuel Disposal Conditions: the Role of Accessory Minerals

1993 ◽  
Vol 333 ◽  
Author(s):  
A. Melamed ◽  
P. Pitkänen
Keyword(s):  
Nuclear Fuel ◽  
Pore Space ◽  
Near Field ◽  
High Water ◽  
Exchange Processes ◽  
Water Ph ◽  
Ca Ions ◽  
Major Alteration ◽  
Granitic Groundwater

ABSTRACTIn an earlier laboratory study1, ion exchange processes and smectite alteration were investigated through the interaction between compacted Na-bentonite (Volclay MX-80) and simulated granitic groundwater solutions. The change of montmorillonite from Na- to Ca-rich was found to be the major alteration process in the bentonite. In the water, a concentration decrease in Ca, Mg and K, and an increase in Na, HCO3 and SO4 were recorded. The total amount of Ca available in the water, however, was found insufficient to account for the recorded formation of Ca-smectite, and it is therefore assumed that the accessory Ca-bearing minerals in the bentonite provide the fundamental source of these cations.X-ray powder diffraction analyses and microscope observations of the bentonite samples were re-conducted. Quartz, feldspars, pyrite, calcite and traces of gypsum were revealed as the primary accessories. In reacted samples, goethite and siderite are found as the secondary mineral products in association with corroded pyrite grains, while calcite and gypsum tend to disappear. From these results it is assumed that the oxygen present in the water and bentonite pore space promotes the oxidation of pyrite (dissolved) and the precipitation of goethite. The pore water pH decreases and calcite is partly dissolved. Through the dissolution, the bulk amount of Ca ions in addition to those arising by diffusion from the water is provided. Some of the reaction-released bicarbonate and Fe2+ re-precipitate in the bentonite as siderite, while the rest (as also SO4 ions) diffuse into the water.Though the relative oxygen content in the experiment may be considered higher than that of the repository concept for nuclear fuel disposal (interaction in a semi-closed system with high water/bentonite ratio), the near field geochemistry predictions imply limited oxidizing conditions, which will be characterized by the above-described processes in sulphide-bearing bentonite and occur for some time after the sealing of the repository.

scholarly journals Richard Dickinson Chambers. 16 March 1935 — 18 April 2019

2020 ◽  
Author(s):  
Graham Sandford
Keyword(s):  
Scale Up ◽  
Valence Bond ◽  
Mirror Image ◽  
Elemental Fluorine ◽  
Exchange Processes ◽  
Halogen Exchange ◽  
Science Community ◽  
Group Members ◽  
Experimental Scientist

Richard (Dick) Chambers was one of the most creative and distinguished organofluorine chemists of his generation. He synthesized a range of perfluorinated heteroaromatic systems, including pentafluoropyridine and tetrafluoropyrimidine, by halogen exchange processes, and established their chemistry and associated reaction mechanisms. Notably, ‘mirror image’ negative Friedel–Crafts reactions led to perfluoroalkyl heteroaromatic derivatives that could be transformed into unusual valence bond isomers by irradiation. New ranges of stable, observable perfluorinated carbanions, alkenes and dienes were synthesized and their fundamental chemistry established. Dick was an excellent experimental scientist whose career was marked by his unique skill-set in being able to perform reactions at high pressure under vacuum, using γ-ray irradiation, photochemistry, continuous flow processes and a variety of fluorinating reagents. His research into the use of elemental fluorine gas, which established the key role of solvent in reaction control, established fluorine as a viable reagent for organic synthesis. Several of his new synthetic processes, including syntheses of perfluorocarbon iodides, highly fluorinated heteroaromatic derivatives and α-fluoro-β-ketoester systems, were adopted for scale-up by industry. But Dick was more than a talented and innovative scientist. He was also an outgoing and fun-loving man, who always made time to offer support, guidance and advice to all his colleagues, research group members and scores of scientific friends within the fluorine science community around the world. As a result, he forged strong personal bonds throughout his life and a legacy that has lasted through generations of chemists.

scholarly journals Organoselenium mild electrophiles in the inhibition of Mpro and SARSCoV-2 replication

2020 ◽  
Author(s):  
Luca Sancineto ◽  
Francesca Mangiavacchi ◽  
Agnieszka Dąbrowska ◽  
Agata Pacuła ◽  
Magdalena Obieziurska-Fabisiak ◽  
...  
Keyword(s):  
Cytopathic Effect ◽  
Selenium Atom ◽  
Inhibition Activity ◽  
Exchange Processes ◽  
Main Protease ◽  
In Vitro Inhibition ◽  
Complex Scenario ◽  
Detoxification Process

New Ebselen-like derivatives resulted to be very strong in vitro inhibitors of SARS-CoV-2 main protease. We demonstrated that this activity mainly depends on the electrophilicity of the selenium atom that is considerably higher in the N-substituted 1,2- benzoselenazol-3(2H)-ones respect to the corresponding diselenides allowing it to be rapidly attached by free thiols affording sulfur-selenium intermediates that are further subjected to thiol exchange processes. This data paints a very complex scenario that requires us to consider Ebselen and Ebselen-like derivatives as potential electrophilic substrates for the several other free thiols present in the cell beside the target free cysteine. The sulfur selenium intermediates are milder electrophiles that could be theoretically implicated in both the detoxification process as well as in the final enzymatic inhibition. We here demonstrated that the in vitro inhibition activity is not fully reproduced in the prevention of viral replication in the cell-based assay. This indicates that the structure of the substituents introduced in the Ebselen scaffold is a crucial factor to control the reactivity of the selenated molecule in the network of thiol exchanges, as well as for molecular recognition of the targeted enzymatic cysteine. For this reason, an in-depth investigation is strongly desirable to better understand how to increase the activity and the selectivity of Ebselen derivatives overcoming the issues of the apparent PAINS-like role of Ebselen. Furthermore, besides the antiviral activity, thee selected compounds also showed a different ability to reduce the virus-induced cytopathic effect, indicating that other mechanisms could be implicated. One may consider here the well-known cytoprotective antioxidant activity of Ebselen and its derivatives.<p></p>

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