Shoot organogenesis in leaf explants of Hydrangea macrophylla ‘Hyd1’ and assessing genetic stability of regenerants using ISSR markers

For the first time, an in vitro regeneration protocol of Hydrangea macrophylla 'Hyd1' was developed. Effects of different plant growth regulators (PGRs) on shoot regeneration were investigated jointly with selecting optimal basal media and cefotaxime concentrations. The highest frequency of shoot organogenesis (100%) and mean number of shoots per explant (2.7) were found on Gamborg B5 basal medium supplemented with 2.25 mg/l 6-benzyladenine (BA), 0.1 mg/l Indole-3-butyric acid (IBA), 100 mg/l cefotaxime and 30 g/l sucrose solidified by 7 g/l agar. Regenerated shoots were rooted by culturing on perlite plus half strength liquid B5 basal medium with 0.5 mg/l NAA. Rooted plantlets were transplanted to the greenhouse with 100% survival rate. Genetic stability of 32 plantlets (one mother plant and 31 regenerants) was assessed by 44 ISSR markers. Out of 44 ISSR markers, ten markers produced clear, reproducible bands with a mean of 5.9 bands per marker. The in vitro regeneration protocol is potentially useful for the genetic transformation of Hydrangea macrophylla 'Hyd1'

A comparative study of three indices of umbilical blood flow in relation to prediction of growth retardation

Peer Reviewe

Effect of viscosity on droplet-droplet collisional interaction

A complete knowledge of the effect of droplet viscosity on droplet-droplet collision outcomes is essential for industrial processes such as spray drying. When droplets with dispersed solids are dried, the apparent viscosity of the dispersed phase increases by many orders of magnitude, which drastically changes the outcome of a droplet-droplet collision. However, the effect of viscosity on the droplet collision regime boundaries demarcating coalescence and reflexive and stretching separation is still not entirely understood and a general model for collision outcome boundaries is not available. In this work, the effect of viscosity on the droplet-droplet collision outcome is studied using direct numerical simulations employing the volume of fluid method. The role of viscous energy dissipation is analysed in collisions of droplets with different sizes and different physical properties. From the simulations results, a general phenomenological model depending on the capillary number (Ca, accounting for viscosity), the impact parameter (B), the Weber number (We), and the size ratio (Δ) is proposed

Experimental and computational investigation of droplet-particle interactions

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An experimental study of droplet-particle collisions

When spray drying a liquid slurry such as milk, collisions between droplets, partially dried particles and completely dry particles are important because coalescence, agglomeration and breakup events influence the size and morphology of the produced powder. When modelling such a spray drying process, it is therefore important to be able to predict the outcomes of individual binary collisions. Both binary dry particle collisions and binary droplet collisions have individually been thoroughly researched over the years due to their widespread occurrence. The importance of understanding binary particle-droplet collisions has been emphasized more recently. However, the number of available studies is limited and simulation studies usually focus on relatively high capillary number. A theory explaining the transition between different regimes is still lacking. The goal of this study is to provide an experimental data set at low capillary number. These results can be used to validate future theories and simulations. To produce and record particle-droplet collisions, an experimental setup that enables synchronized release of both a particle and a droplet was used. One single hanging droplet was released from above onto a particle that initially was held in place by vacuum suction. A high speed camera was synchronized with the setup, and recorded the collisions. Image files were then analysed in Matlab to find velocities and sizes of the particle and droplet before and after impact. The contrast of particle and droplet against the illuminated background was a key factor in succeeding with this. Different collision outcomes were identified as either agglomeration (merging), where the whole droplet would stick to the surface of the particle, or a stretching separation (breaking), where the droplet collides with the particle in an oblique position and stretches out until a part of the droplet detaches from the liquid sticking to the particle. The formation of satellite droplets, i.e. droplets with a radius significantly smaller than the leaving droplet, was also detected. The relation of these collision outcomes to impact conditions such as Weber number and impact parameter was reviewed and put into regime maps

Mapping of the S. demissum late blight resistance gene R8 to a new locus on chromosome IX

The use of resistant varieties is an important tool in the management of late blight, which threatens potato production worldwide. Clone MaR8 from the Mastenbroek differential set has strong resistance to Phytophthora infestans, the causal agent of late blight. The F1 progeny of a cross between the susceptible cultivar Concurrent and MaR8 were assessed for late blight resistance in field trials inoculated with an incompatible P. infestans isolate. A 1:1 segregation of resistance and susceptibility was observed, indicating that the resistance gene referred to as R8, is present in simplex in the tetraploid MaR8 clone. NBS profiling and successive marker sequence comparison to the potato and tomato genome draft sequences, suggested that the R8 gene is located on the long arm of chromosome IX and not on the short arm of chromosome XI as was suggested previously. Analysis of SSR, CAPS and SCAR markers confirmed that R8 was on the distal end of the long arm of chromosome IX. R gene cluster directed profiling markers CDPSw54 and CDPSw55 flanked the R8 gene at the distal end (1 cM). CDPTm21-1, CDPTm21-2 and CDPTm22 flanked the R8 gene on the proximal side (2 cM). An additional co-segregating marker (CDPHero3) was found, which will be useful for marker assisted breeding and map based cloning of R8

Experimental study of the heat transfer in a falling film evaporator: influence of the co-flowing vapor

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.A large number of industrial processes are based on the concentration of liquid products by means of falling-film evaporation. In the dehydration of dairy products, concentrating a fluid by evaporating represents one of the most important steps of the whole drying process. Among the advantages of this technology is that it is possible to operate within small temperature differences which results in low heat consumption. In this sense, it is necessary to increase the amount of removed water during the falling-film evaporation to reduce the energy cost of the overall process. However, reducing the fraction of the solvent leads to an increase in viscosity of the product which can show non-Newtonian features. This aspect significantly affects the heat transfer, that is to say, the higher the solid content, the lower the heat transfer coefficient. One of the possible solutions to this drawback consists in drawing maximum benefit from the interaction between the fluid film and the co-flow of the gaseous phase resulting from the evaporation process. Unfortunately, accurate studies of the effect of co-flow on evaporative falling films are very rare and difficult to perform because of the high costs of the implementation of a suitable experimental apparatus. In this work, the experimental study of the influence of the co-flow on the heat transfer coefficient is presented as a function of both the solid content and the mass flow rate of the feed. The experimental set-up, consisting in a unique industrial pilot scale evaporator, provides the possibility to obtain results useful for realistic industrial conditions. Tests were conducted with varying dry solid content from 10 to 50%. The results show that the co-flow has the effect to decrease the potential for fouling/poor wetting. Above this, the influence on the heat transfer is not as large as expected because of the dominant influence of the viscosity.cf201

The ER-embedded UBE2J1/RNF26 ubiquitylation complex exerts spatiotemporal control over the endolysosomal pathway

The endolysosomal system fulfills a wide variety of cellular functions, many of which are modulated through interactions with other organelles. In particular, the ER exerts spatiotemporal constraints on the organization and motility of endosomes and lysosomes. We have recently described the ER transmembrane E3 ubiquitin ligase RNF26 as a regulator of endolysosomal perinuclear positioning and transport dynamics. Here, we report that the ubiquitin conjugating enzyme UBE2J1, also anchored in the ER membrane, partners with RNF26 in this context, and that the cellular activity of the resulting E2/E3 pair is localized in a perinuclear ER subdomain and supported by transmembrane interactions. Through modification of SQSTM1/p62 on lysine 435, the ER-embedded UBE2J1/RNF26 ubiquitylation complex recruits endosomal adaptors to immobilize their cognate vesicles in the perinuclear region of the cell. The resulting spatiotemporal compartmentalization promotes the trafficking of activated EGFR to lysosomes and facilitates the termination of EGF-induced AKT signaling.Cancer Signaling networks and Molecular Therapeutic

Impact of Serotonin 2C Receptor Null Mutation on Physiology and Behavior Associated with Nigrostriatal Dopamine Pathway Function

The impact of serotonergic neurotransmission on brain dopaminergic pathways has substantial relevance to many neuropsychiatric disorders. A particularly prominent role has been ascribed to the inhibitory effects of serotonin 2C receptor (5-HT2CR) activation on physiology and behavior mediated by the mesolimbic dopaminergic pathway, particularly in the terminal region of the nucleus accumbens. The influence of this receptor subtype on functions mediated by the nigrostriatal dopaminergic pathway is less clear. Here we report that a null mutation eliminating expression of 5-HT2CRs produces marked alterations in the activity and functional output of this pathway. 5-HT2CR mutant mice displayed increased activity of substantia nigra pars compacta (SNc) dopaminergic neurons, elevated baseline extracellular dopamine concentrations in the dorsal striatum (DSt), alterations in grooming behavior, and enhanced sensitivity to the stereotypic behavioral effects of D-amphetamine and GBR 12909. These psychostimulant responses occurred in the absence of phenotypic differences in drug-induced extracellular dopamine concentration, suggesting a phenotypic alteration in behavioral responses to released dopamine. This was further suggested by enhanced behavioral responses of mutant mice to the D1 receptor agonist SKF 81297. Differences in DSt D1 or D2 receptor expression were not found, nor were differences in medium spiny neuron firing patterns or intrinsic membrane properties following dopamine stimulation. We conclude that 5-HT2CRs regulate nigrostriatal dopaminergic activity and function both at SNc dopaminergic neurons and at a locus downstream of the DSt

Impact of serotonin 2C receptor null mutation on physiology and behavior associated with nigrostriatal dopamine pathway function

The impact of serotonergic neurotransmission on brain dopaminergic pathways has substantial relevance to many neuropsychiatric disorders. A particularly prominent role has been ascribed to the inhibitory effects of serotonin 2C receptor (5-HT2CR) activation on physiology and behavior mediated by the mesolimbic dopaminergic pathway, particularly in the terminal region of the nucleus accumbens. The influence of this receptor subtype on functions mediated by the nigrostriatal dopaminergic pathway is less clear. Here we report that a null mutation eliminating expression of 5-HT2CRs produces marked alterations in the activity and functional output of this pathway. 5-HT2CR mutant mice displayed increased activity of substantia nigra pars compacta (SNc) dopaminergic neurons, elevated baseline extracellular dopamine concentrations in the dorsal striatum (DSt), alterations in grooming behavior, and enhanced sensitivity to the stereotypic behavioral effects of D-amphetamine and GBR 12909. These psychostimulant responses occurred in the absence of phenotypic differences in drug-induced extracellular dopamine concentration, suggesting a phenotypic alteration in behavioral responses to released dopamine. This was further suggested by enhanced behavioral responses of mutant mice to the D1 receptor agonist SKF 81297. Differences in DSt D1 or D2 receptor expression were not found, nor were differences in medium spiny neuron firing patterns or intrinsic membrane properties following dopamine stimulation. We conclude that 5-HT2CRs regulate nigrostriatal dopaminergic activity and function both at SNc dopaminergic neurons and at a locus downstream of the DSt.peer-reviewe