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Explicit dimensionless models are proposed for estimating the minimum spouting velocity, operating pressure drop and peak pressure drop in open-sided draft tubes spouted bed using the genetic programming (GP). The models are developed based on 664 experimental data for minimum spouting velocity, 660 for peak pressure drop and 652 for operating pressure drop. The parameters of significant influence are considered as GP input variables, and reliable semi-empirical correlations have been obtained. The models predict the hydrodynamic parameters analyzed with average absolute relative errors of 12.90%, 15.99% and 10.92% for the minimum spouting velocity, peak pressure drop and operating pressure drop, respectively. A comparison of literature correlations with the present ones shows that the latter lead to considerably lower errors from the experimental data. The prediction capability of the new models was evaluated in a range of operating and geometric conditions and a close agreement with the experimental data was observed.

In this study, the intelligent method of genetic programming (GP) was used for developing predictive models for estimating the frost layer thickness under natural and forced convection on ultra-low temperature surfaces. The affecting dimensionless parameters were used as GP input variables, and realistic empirical correlations were developed for estimating the frost thickness under different conditions. The coefficient of determination of 0.9731, 0.9812, and 0.9906, and average absolute relative error of 6.52%, 11.65%, and 2.87%, were obtained by the developed models for natural convection on vertical plates, natural convection on horizontal plates, and forced convection on horizontal plates, respectively. The physical trends of the developed models were evaluated by comparing the model predictions with the experimental data for different operating conditions, and reasonable agreements were obtained. The same experimental database was also compared to some existing correlations for ordinary-low temperature surfaces, but they failed to provide reasonable estimates for the data.

A new general explicit correlation is proposed to predict the heat transfer coefficient of fluids condensing in conventional and mini channels. The expression has been developed by correlating the Numix number with Remix, Prmix, phase density ratio, Pres, WeGT, and FrL using genetic programming for the two-phase flow. The model has been validated with a big dataset consisting of 6521 data samples, covering a wide range of fluids used in refrigeration and heat pump industries, cross-sectional geometries (different diameters), mass fluxes, and saturation temperatures. The new generalized correlation fits the wide range of data points used with an average relative error of 17.82 %. The same database has been used to compare predictions of eight correlations available in the literature, but they failed to give a reasonable estimation of the present experimental results.

Spouted beds are extensively used in different industries. The minimum spouting velocity is a critical hydrodynamic parameter needed for the design and scale-up of these systems. This study deals w...

Platelet degranulation allows the release of large secretable pools of biologically active proteins which are critical in wound healing initiation and angiogenesis. Exosomes, which can transport a diverse suite of macromolecules, derived from amniotic epithelial cells (AEC-Exo) improve wound healing and angiogenesis. However, the underlying mechanisms are still unclear. In this investigation, we performed a user-friendly bioinformatics analysis system to identify association among the angiogenic and wound healing effects of AEC-Exo treatments. To this end, FunRich software was used, and linked to the Universal Protein Resource (UniProt) as a background database. Several enrichment analyses, including biological process, cellular component, molecular function, and protein domains were conducted on AEC-Exo proteome. Furthermore, to identify the proteins involved in platelet degranulation and evaluate protein–protein association information, comparative analyses and interaction network analyses were illustrated using the NCBI BioSystems, ExoCarta, and STRING databases. Our results indicated the statistically significant association between the proteome in AEC-Exo, platelet degranulation, and their corresponding processes. Therefore, the involvement of platelet degranulation in AEC-Exo proteins may elucidate the angiogenic and wound-healing effects of AEC-Exo treatments.

Frost accumulated on heat exchangers' surfaces is a common phenomenon in air-source heat pumps, affecting the heat transfer coefficient and pressure drop, adversely. The mechanism of frost deposition at cryogenic conditions under forced convection (Tw ≤ 100 ° C) shows remarkable differences from those in ordinary-low temperature. The models for predicting frost characteristics on cryogenic surfaces have been rarely reported in the literature. This study aims to model frost density and thickness over ultra-low temperature plates under forced convection. Accordingly, the intelligent models were developed based on radial basis function (RBF), multilayer perceptron (MLP), and Gaussian process regression (GPR) methods using collected measured data from available sources. Although all smart models presented excellent results for training and testing data, the GPR model for frost thickness and RBF model for frost density were designated as top models with AAREs of 1.06% and 0.83%, and R2 values of 99.94% and 99.80%, respectively. The analyzed data were also used for evaluating the precision of earlier models, however, they led to unfavorable results. The developed models exhibited favorable trends under different physical conditions. Besides performing sensitivity analysis, explicit empirical correlations were also obtained with AARE values of 9.38% and 9.68% for estimating frost density and frost thickness, respectively.

Introduction: Doctors undertake calculation of body fat percentage by using BIA (Bioelectrical Impedance Analysis) equipment. In this study, we measured body fat percentage without using equipment. For this purpose, an artificial neural network has been used to estimate the exact amount of fat. Materials & methods: The sample was selected from patients admitted in a nutrition clinic in Tehran. 400 patients took part in this study. MLP neural network was used to estimate body fat percentage. The used neural network had five input neurons and ten neurons in the hidden layer. Also, cross validation method for evaluating the proposed method has been used. Findings: The proposed method is efficient because of the results that demonstrate 2.5 units error based on cross validation. The results of experiments show that the proposed neural network for estimating body fat percentages has an average accuracy of 93%. Therefore the proposed method can accurately estimate body fat percentage of people with very high accuracy. Discussion & conclusions: The results of this research show that the proposed method as the first method used in machine learning technique, can estimate fat percentage with high accuracy. This method can be used as a useful method without using BIA device.

A multilayer perceptron with back-propagation learning algorithm is developed to predict the minimum spouting velocity (ums) in draft tube conical spouted beds. Six dimensionless variables involving ten essential geometric and operating parameters of the beds were taken as model inputs. To compare the model results with both experimental data and those predicted by the limited existing empirical equations, the root mean square error and the mean relative error are utilized. Although there is a complex relationship between the input variables and ums, and despite the huge number of data available, the steps of training and testing show good agreement with the corresponding experimental values. This demonstrates that an artificial neural network is a useful approach to predict ums, especially when the relationship between the geometric and operating parameters and ums is complex and difficult to define.

This study presents the results of an experimental study on the mechanical properties of graphene oxide (GO)-cement mortar composites. Four different mixes of cement mortars with GO contents of 0%, as a control mix, 0.03, 0.1, and 0.5% by the weight of cement were prepared. The effect of the GO content on the axial tension and compression strength of mixes were examined. Scanning electron micrographs (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) tests were performed on the specimens to understand the mechanisms behind the mechanical test results. The results show that the tensile and compressive strength of GO-cement mortar composites steadily increase up to 37.5 and 77.7% with an increase in GO content to 0.1%, respectively. This is attributed to the improved bonding between the cement matrix and GO particles due to the high dispersibility of GO sheets in the composite at the optimum concentration. The results also show that further increase in the GO content was unfavorable as the GO sheets restacked, which reduced the bridging stress and gave poor dispersion of GO in the composite.

A general nonlinear equation for estimating the frictional pressure drop during condensation of fluids in different mini/micro and macro channels was obtained using the genetic programming (GP). The developed model is similar to that of the Lockhart and Martinelli [1] model. For developing the new correlation, 7328 data points were collected from 35 sources, which cover a wide range of fluids, channel geometries, diameters, mass fluxes, and saturation temperatures for single-port and multi-port channels. The newly developed correlation for the two-phase flow predicted a wide range of conditions with an average absolute relative deviation (AARD) of 22.92%. The same database was used for the evaluation of the available empirical correlations. Their deviations were significantly higher than that of the new correlation.

Growth of frost layer on cold fins of tube-fin heat exchangers leads to an increase in the pressure drop and a decrease in the frost thermal conductivity and thereby the heat transfer rate. There is a lack of a general model in the literature for estimating the frost thermal conductivity on parallel plate channels, including almost all parameters affecting this factor. In this study, for the first time, the general explicit semi-empirical correlations consist of dimensionless parameters are developed, which apply to parallel surface channels. The dimensionless input parameters include the wall temperature, air temperature, air velocity, frost porosity, relative humidity, specific heat of moist air, latent heat of sublimation, and operating time. The comparative results indicate that the best correlation predicts data points with an coefficient of determination, average absolute relative error, and relative root mean square error equal 0.9921, 2.755%, and 3.713%, respectively. Other available published correlations present higher deviations using the same dataset. Furthermore, to provide a good insight into this study, a sensitivity analysis is carried out employing the validated model. It is shown that the effective thermal conductivity of the frost layer is not only a function of frost density but also depends on a group of dimensionless parameters. It is observed that the thermal conductivity of the frost layer increases with the increase in the Reynolds number, Fourier number, air humidity, and it decreases with the increase in the dimensionless temperature, modified Jakob number, and porosity.

Milk vetch species (MV) as activated carbon (AC) precursors were prepared and modified by multi-wall carbon nanotubes (CNTs) in order to remove humic acid (HA) removal. Scanning electron microscopy (SEM), diffuse reflectance infrared Fourier transform spectroscopy (FTIR) and Brunauer Emmett Teller (BET) techniques were applied to characterized MVAC/CNTs. The HA adsorption presented the highest value (22.57 mg/g) at pH 3, while the equilibrium state was reached after 30 min. By increasing the adsorbent’s dosage (0.4–0.5 g/L), the removal efficiency was also improved from 90.3 to 97.6%. The kinetics of adsorption were fitted to the pseudo-second-order model (R2 = 0.9991). The Langmuir isotherm model was well fitted to the equilibrium data revealing monolayer adsorption model of HA onto the MVAC/CNTs with the maximum capacity of 73.29 mg/g (R2 = 0.9967). The obtained values of thermodynamic parameters indicated that the HA adsorption was spontaneous, endothermic and physical in nature. Also, genetic programming was used to obtain an appropriate equation revealing the relationship between the variables. The results showed that the introduced equation can successfully predict the HA removal. All experimental results suggested that MVAC/CNTs are promising adsorbents for the contaminated (with HA) water.

Purpose To investigate the effects of daily consuming of green tea on clinical criteria in Periodontitis. Methods Thirty patients with chronic periodontitis were randomly divided into control and experimental groups after scaling and root planning (SRP). Experimental group consumed green tea herbal for 6 weeks and the control group received no intervention. Clinical indices were measured before and 6 weeks after the intervention, and compared for each groups by non-parametric Wilcoxon test and between two groups by Man–Witheny test. Significance level of the test was considered at 95%. Results The results showed that probing depth (PD) and bleeding index (BI) reduced significantly in both groups before and after SRP, this reduction in the intervention group was higher than the control group (P = 0.003 and 0.031, respectively). On the other hand, reducing the amount of plaque index (PI) despite being significant in each group, was not significant between the two groups (P = 0.135). Conclusions According to the results of this study, daily consumption of green tea herbal can have a positive impact on the treatment of periodontal diseases and can be applied as a supplement for improving the effects of phase I periodontal therapy.

Several algorithms based on PageRank algorithm have been proposed to rank the document sentences in the multidocument summarization field and LexRank and T-LexRank algorithms are well known examples. In literature different concepts such as weighted inter-cluster edge, cluster-sensitive graph model and document-sensitive graph model have been proposed to improve LexRank and T-LexRank algorithms (e.g. DsR-G, DsR-Q) for multi-document summarization. In this paper, a density-based graph model for multi-document summarization is proposed by adding the concept of density to LexRank and T-LexRank algorithms. The resulting generic multi-document summarization systems, DensGS and DensGSD were evaluated on DUC 2004 while the query-based variants, DensQS, DensQSD were evaluated on DUC 2006, DUC 2007 and TAC 2010 task A. ROUGE measure was used in the evaluation. Experimental results show that density concept improves LexRank and T-LexRank algorithms and outperforms previous graph-based models (DsR-G and DsR-Q) in generic and query-based multi-document summarization tasks. Furthermore, the comparison of the number of iterations indicates that the density-based algorithm is faster than the other algorithms based on PageRank.

Most research on multi-document summarization explores methods that generate summaries based on queries regardless of the users' preferences. We note that, different users can generate somewhat different summaries on the basis of the same source data and query. This paper presents our study on how to exploit the information regards how users summarized their texts. Models of different users can be used either separately, or in an ensemble-like fashion. Machine learning methods are explored in the construction of the individual models. However, we explore yet another hypothesis. We believe that the sentences selected into the summary should be coherent and supplement each other in their meaning. One method to model this relationship between sentences is by detecting actor---object relationship (AOR). The sentences that satisfy this relationship have their importance value enhanced. This paper combines ensemble summarizing system and AOR to generate summaries. We have evaluated this method on DUC 2006 and DUC 2007 using ROUGE measure. Experimental results show the supervised method that exploits the ensemble summarizing system combined with AOR outperforms previous models when considering performance in query-based multi-document summarization tasks.

The main purpose of this paper is the experimental investigation of an electricity and preheated water cogeneration system by thermoelectric. In the presented design, Fresnel lens and thermoelectric module (TE module) were utilized in order to concentrate solar beam and generate electrical power, respectively. The energy of concentrated sunlight on the heat absorber of TE module is transferred to cold water reservoir. Heat transfer in TE module leads to temperature difference in its both sides and finally electrical power is generated. The main components of this system consist of a monoaxial adjustable structure, a thermoelectric generator (TEG) and a Fresnel lens with an area of 0.09 m 2 . Results revealed that matched load output power is 1.08 W with 51.33% efficiency under radiation intensity of 705.9 W/m 2 . In order to apply TE module capacity optimally for electrical generation, it is recommended to employ an array of Fresnel lenses which transfer heat to TE module by an intermediate fluid.

This study was conducted for evaluating the combined effect of soil moisture, phosphorus (P) and zinc (Zn) levels on crop evapotranspiration (ET), leaf water potential (LWP), water use efficiency (WUE) and various tuber attributes of potato ( Solanum tuberosum L. cv. Agria) under greenhouse conditions. This investigation was conducted as a factorial experiment based on randomized complete blocks design with Zn at three levels (0, 10 and 20 mg Zn per kg dry soil as ZnSO 4 ·7H 2 O), P at three levels (0, 30 and 60 mg P per kg dry soil as Ca(H 2 PO 4 ) 2 ·H 2 O) and soil moisture at three levels (0.5 FC–0.6 FC, 0.7 FC–0.8 FC and 0.9 FC–FC) using three replications. The various attributes of potato tubers including tuber numbers, dry matter content (DM), yield, WUE and indicators of water deficit stress intensity (ET and LWP) were measured routinely during the crop growth period. The results showed that the water deficit stress resulted in a significant decrease in ET, tuber numbers, yield and WUE. Application of P significantly increased the ET, tuber numbers and yield and Zn application significantly affected the tuber numbers. The P × soil moisture interaction effect was significant for ET, LWP, tuber numbers and yield. While the Zn × soil moisture interaction was significant only for yield. The results showed that the two way interactions of Zn, P and soil moisture were mainly synergistic on the most of above mentioned attributes. In general, to achieve the optimum yield of potato tubers in similar soils, application of 10 mg Zn and 30 mg P per kg of dry soil could be recommended under full-irrigated conditions. The regression analysis showed that the yield of potato was increased by application of P under water deficit conditions.

Information about the genetics of callus formation is needed for efficient in vitro selection. Hybrid breeding has been proposed for genetic improvement in the crop, but there isn’t enough information on heterosis for callus growth in crosses among crop genotypes in Iran. In the present study, genetic analysis of three in vitro characters (percentage of callus induction, callus diameter, callus fresh weight) for five inbreed line of rapeseed such as Orakel, ACSN1, P504588, P704591 and Boanty were carried out through a 5 × 5 diallel analysis using calli derived from mature embryo cultures of Brassica napus L. in MS medium. Positive heterosis was noticed for all these characters. Variance component due to specific combining ability (dominance) were larger than general combining ability (additive) for each traits. High broad-sense (70.12 to 89.43) and low narrow-sense (3.49 to 23.01) heritability values suggested that dominance gene action was more important in the genetic control of the characters studied. Orakel, among the five pure lines, was found to have the best genetic background for callus growth rate.

Polyurethane (PU)/Clay nanocomposite rigid foams were synthesized with modified layered silicate clay (organoclays, Cloisite 30B). PU foams were prepared by a batch reaction injection molding process. Organoclay was dispersed first in the isocyanate component using an ultrasonic homogenizer and then mixed with polyol and physical blowing agent mixture to produce nanocomposite PU foams. To study the reaction possibility between cloisite 30B and isocyanate as well as the effect of sonication on the reaction, Fourier transfer infrared (FTIR) analysis was conducted. The dispersion of organoclay in the rigid PU/clay nanocomposite foams was analyzed by wide angle X-ray diffraction (XRD). The microstructure of the foams was studied by an optical microscope and image analysis software. It was concluded that with increasing of nanoclay content the cell size is decreased and the cell size distribution is narrowed. The mechanical properties of pure and nanocomposite foams were examined by compression test. The data obtained from the compressive stress-strain curves reveals that the strength and modulus of polyurethane foam increase by addition of organoclay up to 1wt% and then decrease. Thermal conductivity coefficient (k-factor) of rigid PU nanocomposite and neat foams was measured by a simple transient method. The thermal conductivity results demonstrated that the polyurethane foam k-factor continuously decrease by addition of organoclay. It can be attributed to the reduced cell size as well as narrow cell size distribution in of nanocomposite foams.

In this paper, modeling of physical behavior of plain-woven fabrics under the condition of yarn pullout test is investigated. An analytical model called “the oscillation model” is represented to estimate the required force of yarn pullout test for the plain-woven fabrics. The main idea of this model is based on a combined approach of friction in interlacing points and vibration of yarns during the pullout test. This oscillatory behavior is the outcome of the stick-slip motion, caused directly by contact interactions in interlacing points. In this study, the oscillation model is investigated experimentally for five different plain-woven fabrics. The model includes many physical parameters, which cannot be measured directly. These parameters have been estimated using the force-balance model, which is another analytical model, for predicting the internal mechanical parameters of the plain-woven fabrics in the same test. Experimental results showed that the oscillation model is a suitable approach for anticip...

Titanium dioxide nanoparticles were modified using a sacrificial organic acid carrier at low pH values where the zeta potential of the TiO2 nanoparticles was found to be highly effective forming 0.05, 0.1, 0.5 wt.% Ag/TiO2 nanocomposites. The organic carrier was acting both as an Ag ion carrier and a hole scavenger enhancing the photodeposition of Ag atoms. The formed nanocomposites were calcined at 300 and 400 °C under controlled atmosphere and later examined for photocatalytic performance using a 125 medium pressure mercury lamp decomposing formic acid as an organic pollutant. Morphological, crystallographical and UV–vis spectroscopy analyses were used to characterize the synthesized nanocomposites. The studies have revealed that non-calcined 0.5 wt.% Ag/TiO2 nanocomposite has the best photocatalytic activity compared with other synthesized nanocomposites and that of the non-modified TiO2 (P25). Further calcination of the synthesized nanocomposites has shown to be effective in lower Ag concentrations where 0.1 wt.% Ag/TiO2 nanocomposite has the best photocatalytic activity at the 400 °C.

The commercial potato Solanum tuberosum L. autotetraploid, has many wild relatives with the ploidy range of 2–6×, which are suitable sources of traits interesting in potato breeding. However, not all of these species can be readily crossed with cultivated potato due to pre- and post-zygotic barriers. Post-zygotic barrier on Solanum spp. is attributed to their difference in endosperm balance number (EBN). According to the EBN successful crosses need to have a 2:1 ratio of maternal to paternal EBN in hybrid endosperm. Thus, only parents with the same EBN can be crossed. The cultivated potato is 4EBN, while wild allotetraploid relatives such as S. stoloniferum are 2EBN. In this study, meiosis and crossability of an exceptional tetraploid 3EBN hybrid obtained from our previous research by crossing S. stoloniferum × S. tuberosum with 2 and 4EBN testers were studied. Although the exact chromosome pairing analysis was not possible, the formation of several polyvalents in each meiocyte suggests that recombination could occur between different genomes. Meiosis had many irregularities such as unequal segregation as well as having laggard chromosome and micronuclei. Crosses involving the interspecific hybrid, as the male parent with 2 and 4EBN testers were not successful, some of which were apparently due to the pollen–pistil incompatibility. Interestingly controlled self-pollination resulted in viable seeds. Crosses of the interspecific hybrid as pistillate parent in the absence of pre-zygotic barrier in most case were successful. Results of the study confirmed the segregation of EBN value in the gametes of hybrid. It was expected that backcross progeny of this hybrid would be a good source for selecting aneutetraploids.

Pullout test is a conventional and suitable method to investigate the effects of yarn properties and the structural characteristics of weave on fabric mechanical behaviour. Frictional specifications of the fabric yarns influence the fabric strength and efficiency and its ability to absorb energy. This paper is concerned with formulating an analytical model on yarn pullout force in plain-woven fabrics. The model can predict variations in the internal mechanical parameters of woven fabrics based on a force-balance analysis. These parameters are yarn-to-yarn friction coefficient, normal load at crossovers, lateral forces, lateral strain, weave angle variations, and pullout force. These parameters were predicted using fabric deformation data, which were measured by image processing method during a yarn pullout test and the information of weave angle of fabric, its modulus and density, which were obtained experimentally. Yarn pullout force was calculated through Amonton's friction law to evaluate the ...

Cumin, a member of the Umbelifereae family, is one of the oldest and economically most important spices. Generally, there is limited information about in vitro culture of Cuminum cyminum. A simple method was developed for regeneration of Cumin. This method yielded a large number of shoots within short period of time (30–40 days) without any sub culturing. The effect of different media and various combinations of plant growth regulators (PGRs) on callus formation and shoot regeneration were investigated. Simultaneous callus and shoot regeneration were obtained. The experiment was conducted in a completely randomized design with 30 treatments and 5 replications per treatment. The best response for shoot regeneration was observed on B5 medium containing 0.1 mg l−1 α-Naphthalene acetic acid (NAA) and 4 mg l−1 Kinetin (Kin). The B5 medium containing 2 mg l−1 NAA and 2 mg l−1 Kin was the best treatment for callus and root induction and regeneration simultaneously.

Karyotypic analysis was performed for 11 genotypes of chickpea (Cicer arietinum L.) in order to determine their potential genetic relationships. Pretreatment of root tips in 8-hydroxyquinoline, followed by fixation in Lewitsky solution and hydrolysis in 1N NaOH at 60°C, then staining in aceto-iron-hematoxylin for 15-20 h, confirmed a somatic chromosome number of 2n = 16 in all genotypes. This karyotype consisted of: a pair with the longest satellited submetacentric chromosome, a pair with the shortest metacentric chromosome and six pairs of metacentric to submetacentric chromosomes. Intraspecific variabilities were observed for haploid chromosome length, primary constriction position and karyotypic formula. But all of the studied genotypes showed the same karyotype asymmetry, 1B. Haploid genome length ranged from 24.88 μm±0.50 in G6 (Bieanij cv) to 18.48±0.60 μm in G10 (Flip93-93c cv). Cluster analysis classified the 11 genotypes in three groups, having different sizes of chromosomes and arms.

To date enormous attempts have been devoted to improve Taxol production exploiting various methodologies from bioprocess engineering to biotechnological and synthetic approaches. We have developed a 2-stage suspension cell culture of Taxus baccata L. using modified B5 medium in order to improve cell growth as well as productivity. After callus induction and cell line selection, B5 medium was supplemented with vanadyl sulfate (0.1 mg/l), silver nitrate (0.3 mg/l) and cobalt chloride (0.25 mg/l) at the first day of stage I culture to maximize cell growth. This medium was further supplemented with sucrose (1%) and ammonium citrate (50 mg/l) on day 10 and sucrose (1%) and phenylalanine (0.1 mM) on day 20 (i.e., biomass growth medium). At stage II (day 25), two different concentrations of several elicitors such as methyl jasmonate (10 or 20 mg/l), salicylic acid (50 or 100 mg/l) and fungal elicitor (25 or 50 mg/l) were added to the biomass growth medium with the aim of improving cellular productivity. For morphological analysis, microscopic inspection was carried out during cultivation. Cell-associated and extracellular amount of Taxol were detected and measured using HPLC methodology. At stage I, overall Taxol amount of biomass growth medium was 13.75 mg/l (i.e., 5.6-fold higher than that of untreated B5 control). At stage II, treated cells with methyl jasmonate (10 mg/l), salicylic acid (100 mg/l) and fungal elicitor (25 mg/l) produced the highest amount of Taxol (39.5 mg/l), which is 16-fold higher than that of untreated B5 control (2.45 mg/l). Microscopic analyses of Taxus cells in suspension cultures showed various positional auto-fluorescence showing direct correlation with Taxol production. Our studies revealed that intervallic supplementation of B5 medium with combination of biomass growth factors at stage I and mixture of elicitors at stage II could significantly increase Taxol production. Thus, we suggest that the exploitation of this methodology may improve the production of Taxol since demands for Taxol pharmaceuticals are increasingly growing and resource paucities have limited its direct harvesting from Taxus trees.

Virtual Reality and Virtual Learning Environments have become increasingly ambiguous terms in recent years because of essential elements facilitating a consistent environment for learners. Three-dimensional (3D) environments have the potential to position the learner within a meaningful context to a much greater extent than traditional interactive multimedia environments. The term 3D environment has been chosen to focus on a particular type of virtual environment that makes use of a 3D model. 3D models are very useful to make acquainted students with features of different shapes and objects, and can be particularly useful in teaching younger students different procedures and mechanisms for carrying out specific tasks. This chapter explains that 3D Virtual Reality is mature enough to be used for enhancing communication of ideas and concepts and stimulate the interest of students compared to 2D education.

Molecular epidemiology of hepatitis C virus (HCV) is very important for the treatment of hepatitis C infection. The aim of this study was to determine the distribution of HCV genotypes in Bushehr province (South West of Iran).A total of 100 patients who were detected as positive for HCV antibody (by using ELISA method and RIBA test) referred to Arya Virology Laboratory between 2007-2009 in order to molecular diagnosis and furthermore virus genotyping. After detection of HCV, RNA genotyping of virus was done by using genotype specific primers.Genotype 1a was found in 49% of the patients and genotype 3a was found in 40% of the patients and 1b in 5% of patients, while the genotype of the virus could not be identified in 5% of the patients. Finally, in 1% of patients coinfection due to 1a-3a genotypes was identified.The dominant genotype of HCV in Bushehr province, Iran, was determined as 1a.

The effect of Trichoderma harzianum and Trichoderma viride (isolated from mycoflora in the rhizosphere of onion) in increasing the growth of onion was studied in a completely randomized design in pots with 12 replications under greenhouse conditions at 21°C with a 12-h light/dark cycle (fluorescent and incandescent lighting). The biological control of Sclerotium cepivorum Berk, the causal agent of white rot of onion, was also investigated in this experiment. The addition of Trichoderma spp. to autoclaved soil (inoculation of 2/3 of the top soil in the pots with 4% (v/v) inoculum of T. harzianum and T. viride) significantly increased the growth and fresh weight of the onion plants (P=1%). The biological control of S. cepivorum was achieved with T. harzianum and T. viride, but no significant difference was observed between the two species.

Traditional education for engineers has shifted towards new methods of teaching and learning through the proliferation of Information and Communication Technologies (ICT). The continuous advances in technology enable the realization of a more distributed structure of knowledge transfer. This becomes critically important for developing countries that lack the resources and infrastructure for implementing engineering education practices. The two main themes of technology in designing e-Learning for engineering education in developing countries focus either on aspects of technological support for traditional methods and localized processes, or on the investigation of how such technologies may assist distance learning. Commonly such efforts are threefold, relating to content delivery, assessment and provision of feedback. This chapter is based on the authors ‘10 years’ experience in e-Learning, and reviews themost important key issues and success factors regarding the design of e-Learning for engineering education in developing countries.

Leaf and internode explants of Withania coagulans Dunal were used to evaluate the effect of growth regulators on the in vitro callus induction and plant regeneration. Two independent experiments were performed to establish callus and plant regeneration. In the first experiment, leaf segments were cultured on MS basal medium fortified with 2, 4-dichlorophenoxyacetic acid (2, 4-D, 2-4 mg L(-1)) with combination of 6-benzyladenine (BA, 0.5-1 mg L(-1)) or kinetin (Kin, 0.5-1 mg L(-1)). Callus initiation was observed best in all media after 14-16 days (100%). Highest callus growth in terms of dry weight (76 +/- 5.34 mg) was observed in MS medium fortified with 2 mg L(-1) 2, 4-D and 0.5 mg L(-1) Kin. In the second experiment, callusing also obtained from internode segments cultured on MS medium with the presence of 2, 4-D (2-4 mg L(-1)) in association with BA (0.25-0.5 mg L(-1)). Best callusing rates (42%) and dry weight (86 +/- 3.68 mg) occurred in the presence of 4 mg L(-1) 2, 4-D with combination of 0.25 mg L(-1) BA. Shoot induction was obtained just from callus induced from internode explants on MS medium containing BA (2 mg L(-1)) with IBA (0.5 mg L(-1)), but the yield of shoot regeneration was unsatisfactory (18-33%). Regenerated shoots were rooted best (100%) on half strength MS medium containing IBA (2 mg L(-1)) and produced 23 roots with an average root length of 6.5 +/- 0.41 cm. Rooted plantlets transferred to soil and sand mixture (2:1) showed 75% survival when transferred to outdoor. The procedure reported here in vitro culture of W. coagulans for first time.

The cultivated potato Solanum tuberosum L. is an autotetraploid with Endosperm Balance Number (EBN) of 4. There are some allotetraploid 2EBN wild species with desirable traits for potato improvement. However, it is very difficult to cross between these two groups due to differences in EBN. Eleven genotypes of autotetraploid cultivated potato including the six cultivars of subsp. Tuberosum (tbr) and five clones of subsp. Andigena (adg) were crossed with two wild allotetraploid species: S. acaule (acl) and S. stoloniferum (sto). For asses the pollen-pistil incompatibility, some ofpollinated flowers were fixed in Carnoy's solution and stained with aniline blue. Evaluation with fluorescent microscope revealed that pre-zygotic pollen-pistil incompatibility in these crosses is frequent. The pistils of both subsp. of cultivated potato were incompatible with pollens of acl but when sto used as staminate parent it was compatible with five cultivars of subsp. Tuberosum, but incompatible with most ofsubsp. Andigena (4 clones). From 739, 4x, 4EBN x 4x, 2EBN crosses we couldn't get any viable seed. In reciprocal crosses, allotetraploid species were pollinated with a mix of pollens from Tuberosum or Andigena clones. The crosses of sto x adg, acl x adg and acl x tbr were compatible but in the case of sto x tbr the situation was not clear. From these crosses 157 fruits were obtained but most of them contained only shrink seed and we find just one hybrid from the sto x tbr combination. The hybrid was tetraploid (2n = 4x = 48) and vigorous with profuse flowering and good fertility. When this hybrid was used as the pistillate parent it was compatible with both parental species.

The stress of high environmental temperature may have a deleterious influence on the performance of broiler chickens by reducing feed intake, live weight gain and feed efficiency. Exposing chicks to 36-38°C for 24h at 5d of age reinforces the resistance of older (6 to 7 wk-old) broilers to heat stress (De Basillo et al., 2003). Several studies have revealed that antioxidant nutrient supplementation especially vitamin C and E can be used to alter the negative effect of environmental stress (NRC, 1984). Combination of antioxidant vitamins generally shows greater antioxidant activity than that of each component alone. The objective of this study was to investigate the effects of early age thermal conditioning and vitamin C, E supplementation on performance, carcass characteristic in broiler chickens reared under heat stress.