scholarly journals Modeling and Predicting the Short-Term Evolution of the Geomagnetic Field

2018 ◽  
Vol 123 (6) ◽  
pp. 4539-4560 ◽  
Author(s):  
Julien Bärenzung ◽  
Matthias Holschneider ◽  
Johannes Wicht ◽  
Sabrina Sanchez ◽  
Vincent Lesur
Keyword(s):  
Geomagnetic Field ◽  
Short Term ◽  
Term Evolution

SHORT-TERM EVOLUTION OF FLOW & MORPHOLOGY IN AN ERODIBLE MEANDERING CHANNEL WITH & WITHOUT GROYNES

2018 ◽  
Vol 74 (4) ◽  
pp. I_1147-I_1152
Author(s):  
Saroj KARKI ◽  
Yuji HASEGAWA ◽  
Masakazu HASHIMOTO ◽  
Hajime NAKAGAWA ◽  
Kenji KAWAIKE
Keyword(s):  
Short Term ◽  
Meandering Channel ◽  
Term Evolution ◽  
Flow Morphology

Effects of Dipyridamole on the Short-Term Evolution of Glomerulonephritis

Nephron ◽  
1991 ◽  
Vol 58 (1) ◽  
pp. 13-16 ◽  
Author(s):  
S. Camara ◽  
J.P. de la Cruz ◽  
M.A. Frutos ◽  
P. Sanchez ◽  
Lopez de Novales ◽  
...  
Keyword(s):  
Short Term ◽  
Term Evolution

Physical modeling of the cross-shore short-term evolution of protected and unprotected beach nourishments

2010 ◽  
Vol 37 (8-9) ◽  
pp. 777-789 ◽  
Author(s):  
M. Di Risio ◽  
I. Lisi ◽  
G.M. Beltrami ◽  
P. De Girolamo
Keyword(s):  
Physical Modeling ◽  
Short Term ◽  
Term Evolution ◽  
The Cross

scholarly journals Agrichemicals boost the effects of antibiotics on antibiotic resistance evolution

2018 ◽  
Author(s):  
Brigitta Kurenbach ◽  
Amy M Hill ◽  
William Godsoe ◽  
Sophie van Hamelsveld ◽  
Jack A Heinemann
Keyword(s):  
Antibiotic Resistance ◽  
Acquired Resistance ◽  
Genotypic Diversity ◽  
Microbial Populations ◽  
Phenotypic Variance ◽  
Short Term ◽  
Resistance Evolution ◽  
Term Evolution ◽  
Comprehensive Test ◽  
Selection For

Antibiotic resistance is medicine’s climate change: caused by human activity, and resulting in more extreme outcomes. Resistance emerges in microbial populations when antibiotics act on phenotypic variance within the population. This can arise from either genotypic diversity (resulting from a mutation or horizontal gene transfer), or from ‘adaptive’ differences in gene expression due to environmental variation. Adaptive changes can increase fitness allowing bacteria to survive at higher concentrations of the antibiotic. They can also decrease fitness, potentially leading to selection for antibiotic resistance at lower concentrations. There are opportunities for other environmental stressors to promote antibiotic resistance in ways that are hard to predict using conventional assays. Exploiting our observation that commonly used herbicides can increase or decrease the minimum inhibitory concentration (MIC) of different antibiotics, we provide the first comprehensive test of the hypothesis that the rate of antibiotic resistance evolution under specified conditions can increase, regardless of whether a herbicide increases or decreases the antibiotic MIC. Short term evolution experiments were used for various herbicide and antibiotic combinations. We found conditions where acquired resistance arises more frequently regardless of whether the exogenous non-antibiotic agent increased or decreased antibiotic effectiveness. This “damned if you do/damned if you don’t” outcome suggests that the emergence of antibiotic resistance is exacerbated by additional environmental factors that influence competition between bacteria. Our work demonstrates that bacteria may acquire antibiotic resistance in the environment at rates substantially faster than predicted from laboratory conditions.

Growth phase-dependent UV-C resistance of Bacillus subtilis: data from a short-term evolution experiment

2011 ◽  
Vol 193 (11) ◽  
pp. 823-832 ◽  
Author(s):  
Marko Wassmann ◽  
Ralf Moeller ◽  
Günther Reitz ◽  
Petra Rettberg
Keyword(s):  
Bacillus Subtilis ◽  
Growth Phase ◽  
Short Term ◽  
Term Evolution ◽  
Evolution Experiment ◽  
Uv C

scholarly journals Possible influence of variations in the geomagnetic field on migration paths of snow buntings

2019 ◽  
Vol 19 (2) ◽  
pp. 195-201
Author(s):  
Chris M. Hall ◽  
Magnar G. Johnsen
Keyword(s):  
Magnetic Field ◽  
Geomagnetic Field ◽  
Flight Time ◽  
Short Term ◽  
Breeding Grounds ◽  
Declining Populations ◽  
Plectrophenax Nivalis ◽  
The Individual ◽  
Magnetic North ◽  
The Magnetic Field

AbstractA hypothesis is proposed wherein changes in the Earth's magnetic field affect the migratory paths of snow buntings (Plectrophenax nivalis), and in particular from wintering grounds in the Russian/Ukrainian steppes to breeding grounds on Svalbard and with a typical stopover in Finnmark in northern Norway. If one were to assume ignorance of the secular movement of the magnetic north pole approximately 1500 km northwards between 1908 and 2020, the magnetoreceptor contribution to snow buntings' navigation would result in winter-to-summer migratory paths progressively further to the East. In turn, this could be a contributing factor to declining populations in Finnmark and favouring a more frequent flightpath over the Kola Peninsula. On the other hand, short-term perturbations in the magnetic field (i.e. induced by solar activity) and therefore existing for a relatively small proportion of the flight time (if at all) for the individual migrations legs seem unlikely to influence the stopover locations significantly. Even so, these space-weather induced variations cannot be disregarded, particularly for success in reaching Svalbard.

scholarly journals Possible evolution of the circum-galactic medium around QSOs with QSO age and cosmic time revealed by Ly α haloes

2019 ◽  
Vol 488 (1) ◽  
pp. 120-134 ◽  
Author(s):  
Rieko Momose ◽  
Tomotsugu Goto ◽  
Yousuke Utsumi ◽  
Tetsuya Hashimoto ◽  
Chia-Ying Chiang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Surface Brightness ◽  
Narrow Band ◽  
Cosmic Time ◽  
Black Hole Mass ◽  
Host Galaxies ◽  
Short Term ◽  
Term Evolution ◽  
Similar Growth ◽  
Lower Redshift

ABSTRACT We first present new Subaru narrow-band observations of the Ly α halo around the quasi-stellar object (QSO) CFHQ J232908−030158 at z = 6.42, which appears the most luminous and extended halo at z > 5 (LLy α = 9.8 × 1043 erg s−1 within 37 pkpc diameter). Then, combining these measurements with available data in the literature, we find two different evolutions of QSOs’ Ly α haloes. First is a possible short-term evolution with QSO age seen in four z > 6 QSOs. We find the anticorrelation between the Ly α halo scales with QSOs’ infrared (IR) luminosity, with J2329−0301’s halo being the brightest and largest. It indicates that ionizing photons escape more easily out to circum-galactic regions when host galaxies are less dusty. We also find a positive correlation between IR luminosity and black hole mass (MBH). Given MBH as an indicator of QSO age, we propose a hypothesis that a large Ly α halo mainly exists around QSOs in the young phase of their activity due to a small amount of dust. The second is an evolution with cosmic time seen over z ∼ 2–5. We find the increase of surface brightness towards lower redshift with a similar growth rate to that of dark matter haloes (DHs) that evolve to MDH = 1012–1013 M⊙ at z = 2. The extent of Ly α haloes is also found to increase at a rate scaling with the virial radius of growing DHs, $r_\text{vir} \propto M_\text{DH}^{1/3}(1+z)^{-1}$. These increases are consistent with a scenario that the circum-galactic medium around QSOs evolves in mass and size keeping pace with hosting DHs.

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