The majority of cultivated wheat varieties have glaucous spikes, leaves and leaf sheaths, and the non-glaucous phenotype is rare in modern varieties. The glaucousness/non-glaucousness phenotype is ...not selectively neutral. It was expected that wild wheat may be the source of the allele to control non-glaucousness. We developed near-isogenic lines of durum wheat ‘LD222’ for glaucousness inhibitor loci
Iw1, Iw3
and
Iw4
derived from wild relatives. The
Iw1
locus was derived from ‘MG4343’, an accession of
Triticum dicoccoides
(Körn. ex Asch. et Graebn.) Schweinf. (2n = 4x = 28, BBA
u
A
u
genome), and
Triticum aestivum
L. s. str. (2n = 6x = 42, BBA
u
A
u
DD genome) ‘Shamrock’. The
Iw3
locus in chromosome arm 1BS is unique in tissue specificity of wax regulation in the spikes. The
Iw3
locus was introduced from the lines that originated from crosses with
T. dicoccoides
and
Aegilops speltoides
Tausch (2n = 2x = 14, SS genome) for two near-isogenic lines. The allelic variation for A-genome non-glaucous gene has not been recorded in polyploid wheat. The
Iw4
m
allele for non-glaucousness was introduced from the wild einkorn,
Triticum boeoticum
Boiss. (2n = 2x = 14, A
m
A
m
genome).
Einkorn wheat,
Triticum monococcum
L. (2n = 2x = 14, A
m
A
m
genome), is a primitive, cultivated form of diploid wheat. The shortcoming of einkorn is that it lacks the free-threshing habit. Early ...heading and semi-dwarf traits are also required to fit modern agricultural practice. In the present study we developed
T. monococcum
pre-breeding germplasm having early, free threshing traits by utilizing an early heading source, two sources of soft glume (spike) and three sources of semi-dwarfism to combine their phenotypes into pre-breeding materials. We found two different genes determined free threshing of einkorn wheat. One of them was the
sog
(soft glume) gene from
Triticum sinskajae
Filat. et Kurkiev (2n = 2x = 14, A
m
A
m
genome) and another was the
sos
(
so
ft
s
pike) gene, which was completely linked or pleiotropic with the gene for semi-dwarfism. The genes
sos
,
spd
(
s
hort
p
e
d
uncle) and
sd17654
(
s
emi-
d
warf CItr
17654
) were utilized to develop semi-dwarf
T. monococcum
lines. Field performance of 6 early and free-threshing pre-breeding materials with
sos
and
spd
genes were tested over three crop seasons. Five semi-dwarf pre-breeding materials (PBMs) were obtained. However, these materials had slightly less grain yield than #252 (tall and hulled check) and PBM-1 (tall free-threshing check). Harvest index of the pre-breeding materials was improved due to the presence of
sos
and
spd
genes. If optimized cultivation practice is performed, these pre-breeding materials can be utilized as sources of early, free-threshing and semi-dwarf traits to produce modern
T. monococcum
varieties.
Context. The TESS and PLATO missions are expected to find vast numbers of new transiting planet candidates. However, only a fraction of these candidates will be legitimate planets, and the candidate ...validation will require a significant amount of follow-up resources. Radial velocity (RV) follow-up study can be carried out only for the most promising candidates around bright, slowly rotating, stars. Thus, before devoting RV resources to candidates, they need to be vetted using cheaper methods, and, in the cases for which an RV confirmation is not feasible, the candidate’s true nature needs to be determined based on these alternative methods alone. Aims. We study the applicability of multicolour transit photometry in the validation of transiting planet candidates when the candidate signal arises from a real astrophysical source (transiting planet, eclipsing binary, etc.), and not from an instrumental artefact. Particularly, we aim to answer how securely we can estimate the true uncontaminated star-planet radius ratio when the light curve may contain contamination from unresolved light sources inside the photometry aperture when combining multicolour transit observations with a physics-based contamination model in a Bayesian parameter estimation setting. More generally, we study how the contamination level, colour differences between the planet host and contaminant stars, transit signal-to-noise ratio, and available prior information affect the contamination and true radius ratio estimates. Methods. The study is based on simulations and ground-based multicolour transit observations. The contamination analyses were carried out with a contamination model integrated into the PYTRANSIT v2 transit modelling package, and the observations were carried out with the MuSCAT2 multicolour imager installed in the 1.5 m Telescopio Carlos Sanchez in the Teide Observatory, in Tenerife. Results. We show that multicolour transit photometry can be used to estimate the amount of flux contamination and the true radius ratio. Combining the true radius ratio with an estimate for the stellar radius yields the true absolute radius of the transiting object, which is a valuable quantity in statistical candidate validation, and enough in itself to validate a candidate whose radius falls below the theoretical lower limit for a brown dwarf.
In this paper we describe the OpenGeoSys (OGS) project, which is a scientific open-source initiative for numerical simulation of thermo-hydro-mechanical-chemical processes in porous media. The basic ...concept is to provide a flexible numerical framework (using primarily the Finite Element Method (FEM)) for solving multifield problems in porous and fractured media for applications in geoscience and hydrology. To this purpose OGS is based on an object-oriented FEM concept including a broad spectrum of interfaces for pre- and postprocessing. The OGS idea has been in development since the mid-eighties. We provide a short historical note about the continuous process of concept and software development having evolved through Fortran, C, and C++ implementations. The idea behind OGS is to provide an open platform to the community, outfitted with professional software-engineering tools such as platform-independent compiling and automated benchmarking. A comprehensive benchmarking book has been prepared for publication. Benchmarking has been proven to be a valuable tool for cooperation between different developer teams, for example, for code comparison and validation purposes (DEVOVALEX and CO
2
BENCH projects). On one hand, object-orientation (OO) provides a suitable framework for distributed code development; however, the parallelization of OO codes still lacks efficiency. High-performance-computing efficiency of OO codes is subject to future research.
Shock wave generation by collapse of a single explosive bubble exposed to an underwater shock wave in water has been studied experimentally and numerically. The explosive bubble was made of a ...stoichiometric ethylene-oxygen mixture and its initial volume-equivalent radius was varied from 1.0 to 2.9 mm. The underwater shock wave, whose strength ranged from 7 to 19 MPa, was driven by gasous detonation in a vertical detonation tube. It was found that after passage of the underwater shock wave, the bubble starts to shrink, resulting in explosion just before reaching the minimum radius. In the bubble rebound phase a shock wave is generated whose strength is about twice as compared to that for the air bubble. The maximum pressure of the shock wave nondimensionalized by the ambient pressure behind the underwater shock wave was found to be inversely proportional to the non-dimensional distance. The conversion rate of the bubble energy to the shock energy was estimated to be 0.10, regardless of chemical heat release. Simple numerical analysis of bubble dynamics including compressibility of water was performed. The calculated bubble motion and the shock propagation agree with the experimental results, although the calculated shock strength is overestimated mainly because of non-sphericity of the initial shape of the bubble floating up in water. There is also a good agreement between the experimental and the calculated results in regard to the ratio of the shock pressure for the explosive bubble to that for the air bubble.
ABSTRACT
We present the optical transmission spectrum of the hot Jupiter WASP-104b based on one transit observed by the blue and red channels of the Double Spectrograph (DBSP) at the Palomar 200-inch ...telescope and 14 transits observed by the MuSCAT2 four-channel imager at the 1.52-m Telescopio Carlos Sánchez. We also analyse 45 additional K2 transits, after correcting for the flux contamination from a companion star. Together with the transit light curves acquired by DBSP and MuSCAT2, we are able to revise the system parameters and orbital ephemeris, confirming that no transit timing variations exist. Our DBSP and MuSCAT2 combined transmission spectrum reveals an enhanced slope at wavelengths shorter than 630 nm and suggests the presence of a cloud deck at longer wavelengths. While the Bayesian spectral retrieval analyses favour a hazy atmosphere, stellar spot contamination cannot be completely ruled out. Further evidence, from transmission spectroscopy and detailed characterization of the host star’s activity, is required to distinguish the physical origin of the enhanced slope.
Abstract
Three structural isomers of the C
2
H
4
O
2
molecule, namely, methyl formate (MF; HCOOCH
3
), acetic acid (CH
3
COOH), and glycolaldehyde (HOCH
2
CHO), have attracted considerable attention ...as targets for understanding pathways toward molecular complexity in the interstellar medium (ISM). Among these isomers, MF is decisively abundant in various astronomical objects. For various formation pathways of MF, surface reactions on cosmic dust would play an important role. However, when compared to observations, the formation of MF has been found to be relatively inefficient in laboratory experiments in which methanol (CH
3
OH)-dominant ices were processed by ultraviolet photons and cosmic-ray analogs. Here, we show experimental results on the effective formation of MF by the photolysis of CH
3
OH on water ice at 10 K. We found that the key parameter leading to the efficient formation of MF is the supply of OH radicals by the photolysis of H
2
O, which significantly differs from CH
3
OH-rich experimental conditions. Moreover, using an ultrahigh-sensitivity surface analysis method, we succeeded in constraining the decisive formation pathway of MF via the photolysis of methoxymethanol (MM; CH
3
OCH
2
OH), which would improve our current understanding of chemical evolution in the ISM.
Abstract
Using a combination of photostimulated desorption and resonance-enhanced multiphoton ionization methods, the behaviors of OH radicals on the surface of an interstellar ice analog were ...monitored at temperatures between 54 and 80 K. The OH number density on the surface of ultraviolet-irradiated compact amorphous solid water gradually decreased at temperatures above 60 K. Analyzing the temperature dependence of OH intensities with the Arrhenius equation, the decrease can be explained by the recombination of two OH radicals, which is rate-limited by thermal diffusion of OH. The activation energy for surface diffusion was experimentally determined for the first time to be 0.14 ± 0.01 eV, which is larger than or equivalent to those assumed in theoretical models. This value implies that the diffusive reaction of OH radicals starts to be activated at approximately 36 K on interstellar ice.
PDF
