Diffuse ceiling ventilation for buildings: A review of fundamental theories and research methodologies

The doubled haploid system is the fastest way of hybrid variety production and plays an important role in breeding programs and developmental studies. The most commonly used methods of haploid induction, leading to haploid plants in vitro through the plant tissue/cell culture, are named as the in vitro -based (IVB) methods. These methods have been established in many of the important crops, such as barley, pepper, rapeseed, rice, sugar beet, and wheat. There are ongoing researches to optimize and improve the efficiency of these methods by focusing on factors involved in induction and regeneration phases. These factors mainly include plant genotype, the surrounding environment of parental plants, components of culture medium, the developmental stage of initial gametophytic cells, physical treatments (cold pre-treatment, heat shock) of cultured gametophytic cells, and application of different additives and plant growth regulators. Stress treatment is one of the important prerequisites for stimulation of gametophytic cells to switch towards the sporophytic pathway. However, autophagy and programmed cell death, oxidative stress, and production of reactive oxygen species (ROS) are the major limiting factors in stress-induced embryogenesis. The positive effect of different additives, such as plant growth regulators, chlormequat, polyamines (putrescine, spermidine, and spermine), stress hormones (abscisic acid, jasmonic acid, salicylic acid), DNA demethylating agents and histone deacetylase inhibitors, cellular antioxidants, cell wall remodeling agents (arabinogalactan-proteins), and compatible solutes (proline and chitosan), has been proved on the efficiency of haploid induction through IVB methods. Different mechanisms have been reported through which the aforementioned additives can enhance tolerance to embryo-inducing stresses in plants, and subsequently increase the efficiency of induction phase of IVB methods of haploid induction. Finding the best combination/interaction of inductive stresses and their corresponding chemical enhancers is crucial for successful haploid induction through IVB methods. In the present review, we highlighted recently applied additives to enhance the efficiency of the major IVB methods of haploid induction in different plants. Other potentially applicable additives, those are involved in preventing ROS accumulation, ethylene inhibitors, activating of antioxidant enzyme activity, detoxification capacity, and defense response signal pathway, which could be useful in IVB haploid induction are also discussed. The presented information could be useful to improve the efficiency of developed IVB protocols and/or to develop new protocols in recalcitrant species/genotypes.

In vitro-based doubled haploid production: recent improvements

Numerical analysis of natural convection combined with entropy generation in a square open cavity partially filled with a porous medium has been performed for a ferrofluid under the effect of incli...

Effect of uniform inclined magnetic field on natural convection and entropy generation in an open cavity having a horizontal porous layer saturated with a ferrofluid

Doubled haploids, subsequent to haploid induction, have wide range of applications in basic and applied plant studies. Various parameters can affect the efficiency of haploid induction through an anther culture of tomato. The hybrid system of image processing-artificial neural network (ANN) was used to better understand callus induction and regeneration in an anther culture of tomato. The effect of parameters such as plant genotype, the concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin (Kin) plant growth regulators, the concentration of gum arabic (GA) additive, the cold pretreatment duration, and flower length on callus induction percentage and number of regenerated calli in an anther culture of tomato were studied using multiple linear regression (MLR) and ANN models. The precise flower bud length was measured using an image processing technique. The 4′,6-diamidino-2-phenylindole (DAPI) analysis showed that the flowers with 5–6.9 mm length had the highest percentage of the mid- to late-uninucleate microspore stage. The best ANN model for both callus induction percentage and number of regenerated calli was a model with one hidden layer, 12–15 neurons in the first hidden layer, Levenberg–Marquardt learning algorithm, and Tan-Sigmoid transfer function in hidden layer, based on the root mean square error (RMSE), mean absolute error (MAE), and coefficient of determination (R2) statistics. The scatter plot of measured values versus the predicted values showed the superiority of the ANN to MLR model to predict the callus induction percentage in an anther culture of tomato. The sensitivity analysis of MLR and ANN models revealed the plant genotype and 2,4-D concentration as the most important factors affecting both callus induction percentage and number of regenerated calli. Since tomato is a recalcitrant plant to androgenesis-based pathway of haploid induction, therefore the results of the present study can be helpful to develop an efficient haploid induction protocol in tomato through an anther culture pathway.

Modeling callus induction and regeneration in an anther culture of tomato (Lycopersicon esculentum L.) using image processing and artificial neural network method

Simulations and experiments have been carried out to investigate heat transfer and thermodynamic processes in coal-bearing strata in order to quantitatively understand the development of underground coal fires under the spontaneous combustion condition. With the controlled temperature and under lean oxygen conditions, the thermodynamic parameters for coal oxidation at different stages are experimentally determined in combination with the simultaneous thermal analysis. A combined heat transfer model of conduction, convection, and radiation with finite reactions is developed for the porous coal and rocks. The temperature distributions in the coal and roof strata at different times are simulated based on the single- and two-stage kinetic models, respectively, and compared with field geophysical prospecting. Effects of oxidation kinetic properties due to coal metamorphism on propagation of coal fires are examined. It reveals that a significant step change exists during the thermal process of coal fire...

Heat transfer and thermodynamic processes in coal-bearing strata under the spontaneous combustion condition

Industrial waste filled polymer composites – A review

This article deals with the analysis of combined mode conduction and radiation heat transfer in a porous medium, and simultaneous estimation of the optical properties of the porous matrix. Simultaneous solution of the gas- and solid-phase energy equations encompasses local thermal nonequilibrium, while the convective heat exchange term couples the gas- and the solid-phase energy equations. A localized uniform volumetric heat generation zone is the source of heat transfer in the porous matrix. With volumetric radiative information needed in the solid-phase energy equation computed using the discrete transfer method, the solid- and gas-phase energy equations are simultaneously solved using the finite difference method. For a given set of boundary conditions and operating parameters, the computed temperature distribution serves as the exact temperature profile necessary in the estimation of parameters. In the estimation of parameters using inverse analysis, the objective function is minimized using the genet...

Combined Mode Conduction and Radiation Heat Transfer in a Porous Medium and Estimation of the Optical Properties of the Porous Matrix

This study describes the development of haploid plantlets through androgenesis in Camellia assamica ssp. assamica (tea). Androgenic haploid embryos were produced through callus formation from microspores during the early-to-late uninucleate stages in anther cultures. A high percentage of callus induction (96%) was obtained on Murashige and Skoog’s (MS) medium containing 6% (w/v) glucose, supplemented with 5 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 5 μM 6-furfurylaminopurine (kinetin), 800 mg L−1 L-glutamine, and 200 mg L−1 L-serine (callus induction medium). Further proliferation of callus occurred when glucose was replaced with 3% (w/v) sucrose in the medium. Embryogenesis was achieved in 85% of the androgenic callus cultures on MS medium containing 10 μM 6-benzylaminopurine (BAP), 3 μM gibberellic acid (GA3), 800 mg L−1 L-glutamine, and 200 mg L−1 L-serine (embryo induction medium). Maturation of embryos occurred when the concentration of the growth regulators and adjuvants contained in the embryo induction medium were reduced by tenfold. Embryos germinated into complete plantlets in 65% of the cultures when the MS medium was supplemented with 10 μM BAP, 1 μM indole-3-butyric acid (IBA), 0.5 μM GA3, 80 mg L−1 L-glutamine, and 20 mg L−1 L-serine. These plantlets continued to grow when the major salt concentration in the embryo germination medium was reduced by half (1/2 MS). The chromosomal constitution of these in vitro plantlets was confirmed as 2n = X = 15 by cytological squash preparation of the root tips. Flow cytometric analysis of leaves from these in vitro plantlets confirmed the ploidy status as haploid. This study is an effort to overcome the inherent heterozygosity in tea.

An efficient and reproducible method for development of androgenic haploid plants from in vitro anther cultures of Camellia assamica ssp. assamica (Masters)

Polymer composites for thermal applications – A review

This article reports a study on simultaneous estimation of four parameters for combined-mode conduction and radiation heat transfer in a 2D rectangular porous matrix with a localized volumetric hea...

Vijay Kumar Mishra

Papers

Industrial waste filled polymer composites – A review

Combined Mode Conduction and Radiation Heat Transfer in a Porous Medium and Estimation of the Optical Properties of the Porous Matrix

An efficient and reproducible method for development of androgenic haploid plants from in vitro anther cultures of Camellia assamica ssp. assamica (Masters)

Polymer composites for thermal applications – A review

Simultaneous estimation of four parameters in a combined-mode heat transfer in a 2D porous matrix with heat generation