scholarly journals Measuring the properties of reionized bubbles with resolved Lyα spectra

2020 ◽  
Vol 499 (1) ◽  
pp. 1395-1405 ◽  
Author(s):  
Charlotte A Mason ◽  
Max Gronke†
Keyword(s):  
Galaxy Evolution ◽  
Resonant Absorption ◽  
Neutral Fraction ◽  
Line Of Sight ◽  
Proof Of Concept ◽  
Gas Density ◽  
Lyman Alpha ◽  
Thin Region ◽  
Spectrally Resolved ◽  
The Relationship

ABSTRACT Identifying and characterizing reionized bubbles enables us to track both their size distribution, which depends on the primary ionizing sources, and the relationship between reionization and galaxy evolution. We demonstrate that spectrally resolved z ≳ 6 Lyman-alpha (Lyα) emission can constrain properties of reionized regions. Specifically, the distance from a source to a neutral region sets the minimum observable Lyα velocity offset from systemic. Detection of flux on the blue side of the Lyα resonance implies the source resides in a large, sufficiently ionized region that photons can escape without significant resonant absorption, and thus constrains both the sizes of and the residual neutral fractions within ionized bubbles. We estimate the extent of the region around galaxies which is optically thin to blue Lyα photons, analogous to quasar proximity zones, as a function of the source’s ionizing photon output and surrounding gas density. This optically thin region is typically ≲ 0.3 pMpc in radius (allowing transmission of flux ≳ −250 km s−1), ≲ 20 per cent of the distance to the neutral region. In a proof-of-concept, we demonstrate the z ≈ 6.6 galaxy COLA1 – with a blue Lyα peak – likely resides in an ionized region >0.7 pMpc, with residual neutral fraction <10−5.5. To ionize its own proximity zone we infer COLA1 has a high ionizing photon escape fraction (fesc > 0.50), relatively steep UV slope (β < −1.79), and low line-of-sight gas density (∼0.5 times the cosmic mean), suggesting it is a rare, underdense line-of-sight.

scholarly journals Targeted Allele Replacement Mutagenesis of Corynebacterium pseudotuberculosis

2011 ◽  
Vol 77 (10) ◽  
pp. 3532-3535 ◽  
Author(s):  
Caray A. Walker ◽  
Willie Donachie ◽  
David G. E. Smith ◽  
Michael C. Fontaine
Keyword(s):  
Corynebacterium Pseudotuberculosis ◽  
Sequence Length ◽  
Homologous Sequence ◽  
Proof Of Concept ◽  
Rolling Circle Replication ◽  
Content Type ◽  
Rolling Circle ◽  
Allele Replacement ◽  
Marker Free ◽  
The Relationship

ABSTRACTA two-step allele replacement mutagenesis procedure, using a conditionally replicating plasmid, was developed to allow the creation of targeted, marker-free mutations inCorynebacterium pseudotuberculosis. The relationship between homologous sequence length and recombination frequency was determined, and enhanced plasmid excision was observed due to the rolling-circle replication of the mutagenesis vector. Furthermore, an antibiotic enrichment procedure was applied to improve the recovery of mutants. Subsequently, as proof of concept, a marker-free,cp40-deficient mutant ofC. pseudotuberculosiswas constructed.

MERGE OF THE TECHNİCAL ANALYSİS TYPES GİVES THE BEST RESULTS İN CRYPTOCURRENCY MARKET

2021 ◽  
Vol 6 (14) ◽  
pp. 89-97
Author(s):  
MUSTAFA ÖZYEŞİL ◽  
MOHAMMAD AL-TARIFI
Keyword(s):  
Supply And Demand ◽  
Investment Strategy ◽  
Proof Of Concept ◽  
Market Capitalization ◽  
Long Run ◽  
Peer Network ◽  
Tangible Asset ◽  
The Relationship ◽  
Peer To Peer Network

Cryptocurrencies are a modern kind of financial instrument (Hudson & Urquhart, 2019), the first cryptocurrency is Bitcoin , proposed by who called Satoushi Nakamato (2008), as The open source was created on the proof-of-concept principle that transactions can be securely treated on a decentralized peer to peer network without the need for a central clearinghouse, which appeared 2009 ( Heid, 2013). The success of the bitcoin blazes a trail to what called ‘Altcoin” this expression means all the cryptocurrencies that set in motion after the victory of the bitcoin, these coins sell themselves as the best alternatives for the bitcoin (FRANKENFIELD, 2020) . There are many types for the altcoin. The third type of the cryptocurrency is called Tokens Unlike Bitcoin and Altcoins, tokens are not able to activate independently and are dependent on the grid of another cryptocurrency. That means they do not have their own core DLT or blockchain, but instead, are built on top of an existing cryptocurrency’s blockchain (Types of cryptocurrencies: explaining the major types of cryptos, 2019). The worth of bitcoin doesn’t depend on any tangible asset or economies of the countries while it is based upon the security of an algorithm which traces all transactions (Hudson & Urquhart, 2019). The studies determine the number of the bitcoin price development in the long -run (Ciaian, Rajcaniova, & Kancs, 2018): • Market forces of the Bitcoin supply and demand • The bitcoin’s attractiveness for the investors • The influence of global macro-financial developments If you're forming an investment strategy designed to help you trail long-term financial intentions, understanding the relationship between company size, return potential, and risk is vital. (Market cap—or market capitalization—refers to the total value of all a company's shares of stock, 2017) .Hence , Manifested importance a cryptocurrency’s market capitalization as the total values of all coins currently in circulation. the cryptocurrency’s market cap contains what’s called Bitcoin Dominance that is the ratio between the market cap of bitcoin to other coins of the cryptocurrency markets (jacobcanfield, 2019) . Cryptocurrency trade is attractive type of investment. this market treated the same of the foreign exchange and stock market ( Radityo, Munajat, & Budi, 2017). The investors using the same basic in investment (buy low, sell high) but they need to calculating the risks

The Line of Sight of ϵ Canis Majoris: Depletion and Extent of the Local Cloud

1997 ◽  
Vol 166 ◽  
pp. 161-164
Author(s):  
Cécile Gry ◽  
Olivier Dupin
Keyword(s):  
High Resolution ◽  
Column Density ◽  
Uv Spectra ◽  
Line Of Sight ◽  
Gas Density ◽  
Neutral Gas ◽  
Local Cloud

AbstractWith new high resolution UV spectra of ϵ CMa we show that the gas column density in this sight-line is less than 4 1017 cm−2, that the neutral gas density is less than 10−5 cm−3 after the first 3 parsecs, and that the Local Cloud seems to be almost undepleted and to extend to no more than 0.6 pc in this direction.

scholarly journals Diffuse Interstellar Bands in M33

2013 ◽  
Vol 9 (S297) ◽  
pp. 74-78
Author(s):  
K. T. Smith ◽  
M. A. Cordiner ◽  
C. J. Evans ◽  
N. L. J. Cox ◽  
P. J. Sarre
Keyword(s):  
Equivalent Width ◽  
Milky Way ◽  
Line Of Sight ◽  
Nearby Galaxy ◽  
Diffuse Interstellar Bands ◽  
Upper Limits ◽  
Interstellar Media ◽  
The Relationship

AbstractWe present the first sample of diffuse interstellar bands (DIBs) in the nearby galaxy M33. Studying DIBs in other galaxies allows the behaviour of the carriers to be examined under interstellar conditions which can be quite different from those of the Milky Way, and to determine which DIB properties can be used as reliable probes of extragalactic interstellar media. Multi-object spectroscopy of 43 stars in M33 has been performed using Keck/DEIMOS. The stellar spectral types were determined and combined with literature photometry to determine the M33 reddenings E(B-V)M33. Equivalent widths or upper limits have been measured for the λ5780 DIB towards each star. DIBs were detected towards 20 stars, demonstrating that their carriers are abundant in M33. The relationship with reddening is found to be at the upper end of the range observed in the Milky Way. The line of sight towards one star has an unusually strong ratio of DIB equivalent width to E(B-V)M33, and a total of seven DIBs were detected towards this star.

scholarly journals The Explorer of Diffuse Galactic Emission (EDGE)

2005 ◽  
Vol 13 ◽  
pp. 971-971
Author(s):  
R. F. Silverberg ◽  
E. S. Cheng ◽  
D. A. Cottingham ◽  
D. J. Fixsen ◽  
L. Knox ◽  
...  
Keyword(s):  
Galaxy Evolution ◽  
Large Scale ◽  
Microwave Background ◽  
Complementary Information ◽  
Subsequent Evolution ◽  
Galaxy Surveys ◽  
Lyman Alpha ◽  
Test Models ◽  
Galactic Emission ◽  
Infrared Background

The details of the formation of the first objects, stars and galaxies and their subsequent evolution remain a cosmological unknown. Few observational probes of these processes exist. The Cosmic Infrared Background (CIB) originates from this era and measurements of its anisotropy can provide information to test models of both galaxy evolution and the growth of primordial structure. Such measurements should provide a sensitive probe of the large-scale variation in protogalaxy density at redshifts, z ~ 0.5-3, while optical galaxy surveys provide complementary information at z < 0.5 and Lyman alpha absorption forest studies and Cosmic Microwave Background measurements add information at higher redshifts.

scholarly journals Consensus of Fractional-Order Multiagent Systems with Double Integral and Time Delay

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Jun Liu ◽  
Wei Chen ◽  
Kaiyu Qin ◽  
Ping Li
Keyword(s):  
Time Delay ◽  
Fractional Order ◽  
Network Topology ◽  
Proof Of Concept ◽  
State Variables ◽  
Double Integral ◽  
Order Model ◽  
Fractional Order Model ◽  
The Relationship ◽  
Double Integrator

This paper is devoted to the consensus problems for a fractional-order multiagent system (FOMAS) with double integral and time delay, the dynamics of which are double-integrator fractional-order model, where there are two state variables in each agent. The consensus problems are investigated for two types of the double-integrator FOMAS with time delay: the double-integrator FOMAS with time delay whose network topology is undirected topology and the double-integrator FOMAS with time delay whose network topology is directed topology with a spanning tree in this paper. Based on graph theory, Laplace transform, and frequency-domain theory of the fractional-order operator, two maximum tolerable delays are obtained to ensure that the two types of the double-integrator FOMAS with time delay can asymptotically reach consensus. Furthermore, it is proven that the results are also suitable for integer-order dynamical model. Finally, the relationship between the speed of convergence and time delay is revealed, and simulation results are presented as a proof of concept.

Baroreceptors, baroreceptor unloading, and the long-term control of blood pressure

2005 ◽  
Vol 288 (4) ◽  
pp. R819-R827 ◽  
Author(s):  
Terry N. Thrasher
Keyword(s):  
Animal Studies ◽  
Sympathetic Nerve Activity ◽  
Human Subjects ◽  
Pressure Change ◽  
Proof Of Concept ◽  
Experimental Proof ◽  
Pulsatile Pressure ◽  
Compliance Map ◽  
The Relationship

Whether arterial baroreceptors play a role in setting the long-term level of mean arterial pressure (MAP) has been debated for more than 75 years. Because baroreceptor input is reciprocally related to efferent sympathetic nerve activity (SNA), it is obvious that baroreceptor unloading would cause an increase in MAP. Experimental proof of concept is evident acutely after baroreceptor denervation. Chronically, however, baroreceptor denervation is associated with highly variable changes in MAP but not sustained hypertension. The ability of baroreceptors to buffer imposed increases in MAP appears limited by a process termed “resetting,” in which the threshold to fire shifts in the direction of the pressure change and if the pressure elevation is maintained, it leads to a rightward shift in the relationship between baroreceptor firing and MAP. The most common hypothesis linking baroreceptors to changes in MAP proposes that reduced vascular distensibility in baroreceptive areas would cause reduced firing at the same pulsatile pressure and, thus, reflexively increase SNA. This review focuses on effects of baroreceptor denervation in the regulation of MAP in human subjects compared with animal studies; the relationship between vascular compliance, MAP, and baroreceptor resetting; and, finally, the effect of chronic baroreceptor unloading on the regulation of MAP.

scholarly journals The space distribution of the Lyman alpha clouds in the line of sight to the z=3.66 QSO 0055-269

1995 ◽  
Vol 273 (4) ◽  
pp. 1016-1032 ◽  
Author(s):  
S. Cristiani ◽  
S. D'Odorico ◽  
A. Fontana ◽  
E. Giallongo ◽  
S. Savaglio
Keyword(s):  
Space Distribution ◽  
Line Of Sight ◽  
Lyman Alpha

CELLULAR ANTOMATA

2012 ◽  
Vol 15 (06) ◽  
pp. 1250070 ◽  
Author(s):  
ARNOLD L. ROSENBERG
Keyword(s):  
Path Planning ◽  
Finite Size ◽  
Proof Of Concept ◽  
Food Items ◽  
The World ◽  
Constrained Environments ◽  
Food Seeking ◽  
The Relationship ◽  
Novel Model ◽  
Factory Laboratory

Problems involving path planning, exploration, and related activities abound in the world of computing. This paper develops a novel model for realizing ant-inspired algorithms that coordinate robots within fixed, geographically constrained environments ("factory/laboratory/warehouse floors") and studies the model via sample tasks that illustrate various aspects of path planning and exploration. The model, dubbed a Cellular ANTomaton (C-ANTomaton, for short), inverts the relationship between ant-robots and the environments that they navigate: "Intelligence" now resides in the "floor" rather than in the ant-robots. The C-ANTomaton model is illustrated via three proof-of-concept problems: (1) Parking requires ant-robots to congregate in their nearest corners of the "floor," in a maximally compact formation. (2) Food-seeking (both with and without impenetrable obstacles) requires each ant-robot to find its own "food" item, until either "foodless" ant-robots or unclaimed "food" items run out. (3) Maze-threading requires a single ant-robot to find the unique exit to a maze. "Unintelligent" C-ANTomaton-based robots accomplish all of these goals provably more efficiently than traditional "intelligent" ant-robots can; indeed, "intelligent" ant-robots cannot always park at all! All of the presented algorithms are scalable, in that they provably work for any number of ant-robots, within any finite-size "floor." In other words, the computers that collectively supply the system with "intelligence" never exploit any information about either the number of ant-robots or the size of the "floor."

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