Research Notes : India : Intra-plant variation in mutation frequency and spectrum in soybean

Upadhyaya (1976) observed that the number of mutant plants was exceedingly low in segregating M2 progenies in soybean. In M3 progenies of normal M2 plants, the number of segregating progenies was also not very high as compared with nonsegregating progenies. But, all the segregating progenies in MJ generation showed an excellent fit to the 3 normal:l mutant ratio, indicating mutant as a monogenic recessive trait. Such a situation was encountered in many cases of albino, yellow leaf, crinkled leaf, and sterile mutants

Validation of a laboratory method for evaluating dynamic properties of reconstructed equine racetrack surfaces.

BackgroundRacetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.ObjectiveTo develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties.MethodsTrack-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack) and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression.ResultsMost dynamic surface property setting differences (racetrack-laboratory) were small relative to surface material type differences (dirt-synthetic). Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.ConclusionsLaboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD).Potential relevanceDynamic impact properties of race surfaces can be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions

Geotechnical Problems Encountered During the Excavation of Underground Cavities for Varahi Hydro Electric Project

Varahi river in Karnataka State, India originates on the Western Ghats and is harnessed for power generation by constructing three dams. The water is conveyed through two inclined pressure shaft to the underground power house below the Ghats. The underground power house of the Varahi Hydro Electric Project executed by the Karnataka Power Corporation has 2 units of 135 MW each in the first stage with a provision to add two more identical units. Three underground cavities are excavated parallel to one another for housing the rotary valves, generators and the transformers respectively and are at a gee-static head of about 230 m. The paper deals with a case history of the excavation practice and the stabilisation measures adopted during the excavation of the cavities for housing the underground power house complex of the Varahi Hydro Electric Project in Karnataka, India

Automated tight Lyapunov analysis for first-order methods

We present a methodology for establishing the existence of quadratic Lyapunov inequalities for a wide range of first-order methods used to solve convex optimization problems. In particular, we consider i) classes of optimization problems of finite-sum form with (possibly strongly) convex and possibly smooth functional components, ii) first-order methods that can be written as a linear system on state-space form in feedback interconnection with the subdifferentials of the functional components of the objective function, and iii) quadratic Lyapunov inequalities that can be used to draw convergence conclusions. We provide a necessary and sufficient condition for the existence of a quadratic Lyapunov inequality that amounts to solving a small-sized semidefinite program. We showcase our methodology on several first-order methods that fit the framework. Most notably, our methodology allows us to significantly extend the region of parameter choices that allow for duality gap convergence in the Chambolle-Pock method when the linear operator is the identity mapping

High mobility titanium-doped indium oxide for use in tandem solar cells deposited via pulsed DC magnetron sputtering

© 2014 The Authors. The effects of pulsed DC (PDC) magnetron sputtering on the crystalline structure of the high mobility transparent conducting oxide (TCO), titanium-doped indium oxide (ITiO), are investigated. High mobility (μ >100 V-1s-1cm2) ITiO films are deposited by PDC magnetron sputtering and compared to RF deposited films using optimized conditions. These high mobility ITiO films have shown to extend the transmission in the NIR region compared to typical TCOs, such as ITO, exhibiting their potential in a tandem or multiple junction solar cell application. ITiO films deposited by PDC magnetron sputtering offer an increased deposition rate without a significant reduction in mobility when compared to RF sputtering, thus potentially offering PDC as a preferred industrial choice over RF sputtering. Structural characterization of the ITiO films prepared by PDC show a change in crystalline orientation and crystallite shape when compared to RF films, measured by XRD and SEM, which have been linked with the electrical parameters of the TCO

Origin of germ cells and formation of new primary follicles in adult human ovaries

Recent reports indicate that functional mouse oocytes and sperm can be derived in vitro from somatic cell lines. We hypothesize that in adult human ovaries, mesenchymal cells in the tunica albuginea (TA) are bipotent progenitors with a commitment for both primitive granulosa and germ cells. We investigated ovaries of twelve adult women (mean age 32.8 ± 4.1 SD, range 27–38 years) by single, double, and triple color immunohistochemistry. We show that cytokeratin (CK)+ mesenchymal cells in ovarian TA differentiate into surface epithelium (SE) cells by a mesenchymal-epithelial transition. Segments of SE directly associated with ovarian cortex are overgrown by TA, forming solid epithelial cords, which fragment into small (20 micron) epithelial nests descending into the lower ovarian cortex, before assembling with zona pellucida (ZP)+ oocytes. Germ cells can originate from SE cells which cover the TA. Small (10 micron) germ-like cells showing PS1 meiotically expressed oocyte carbohydrate protein are derived from SE cells via asymmetric division. They show nuclear MAPK immunoexpression, subsequently divide symmetrically, and enter adjacent cortical vessels. During vascular transport, the putative germ cells increase to oocyte size, and are picked-up by epithelial nests associated with the vessels. During follicle formation, extensions of granulosa cells enter the oocyte cytoplasm, forming a single paranuclear CK+ Balbiani body supplying all the mitochondria of the oocyte. In the ovarian medulla, occasional vessels show an accumulation of ZP+ oocytes (25–30 microns) or their remnants, suggesting that some oocytes degenerate. In contrast to males, adult human female gonads do not preserve germline type stem cells. This study expands our previous observations on the formation of germ cells in adult human ovaries. Differentiation of primitive granulosa and germ cells from the bipotent mesenchymal cell precursors of TA in adult human ovaries represents a most sophisticated adaptive mechanism created during the evolution of female reproduction. Our data indicate that the pool of primary follicles in adult human ovaries does not represent a static but a dynamic population of differentiating and regressing structures. An essential mission of such follicular turnover might be elimination of spontaneous or environmentally induced genetic alterations of oocytes in resting primary follicles

Induced Variability in Soybean

The magnitude of induced genetic variability for different quantitative characters was estimated in the M3 generations of seven soybean [Glycine max (L.) Merril] varieties irradiated with 10 kr, 15 kr and 20 kr gamma rays. In mean performance irradiated populations were not significantly different from the unirradiated populations for most of the characters. However, the total variances within irradiated populations were significantly higher than the variances in control populations for most of the characters indicating induced genetic variability. The magnitude of differences in variance for yield/plant was highest between ‘Ankur’ 15 kr and ‘Ankur’ 0 kr