Effect of pot size, planting date and genotype on minituber production of Marfona potato cultivar

This study was carried out to evaluate the effects of pot size, planting date and type of genotype on mini-tuber production of Marfona potato cultivar (Solanum tuberosum L.) in greenhouse conditions.Four genotypes (M-129, M-128P, M-127P and M-124P) originated from virus free sprouts and a genotype of the same cultivar (Marfona) originated from apical meristem, in 3 sizes of pot and 3 planting datewere investigated. The results showed that using larger pots of 3-liter has no advantage and pots smaller than 2-liter is not suitable for mini-tuber production. Also, time of Nov 18 was the best of datefor planting of potato in studied conditions and delay in date of planting reduced the mini-tuber production. The reduction in number of mini-tubers and growing period was greater for the genotype M-129 compared with the other potato genotypes. Furthermore, higher numbers of mini-tubers were produced by the M-127P and M-124P genotypes and M-127P had the highest total weight of mini-tubers.However the number of mini-tubers per plant was higher for genotypes originated from meristem culture than genotypes obtained from sprouts. It seems that genotypes originated from potato sprouts are not as efficient as the apical meristem ones. On the other hand, later genotype showed more homogenous in growth rate and phenotype

Hierarchical control in microgrid

It is required to utilize several control loops together to increase reliability and performance of microgrids. The current and voltage magnitudes, frequency and angle information, active and reactive power data provide the involved feedback for normal and island mode operations of microgrid. The hierarchical control structure of microgrid is responsible for microgrid synchronization, optimizing the management costs, control of power share with neighbor grids and utility grid in normal mode while it is responsible for load sharing, distributed generation, and voltage/frequency regulation in both normal and islanding operation modes. The load control of microgrid is performed by using more sophisticated electronic devices as well as regular circuit breakers. This regulation capacity could be improved since the ESS decreases the dependency to primary power sources. Although several improvements have been experienced in microgrid control strategies, the most intensive research areas are listed as decreasing the structural instability, improving the system performance to increase reliability, monitoring the harmonic contents, scaling the control infrastructure, enhancing the operation characteristics in error states, and implementing new control algorithms for normal and islanding operation. The microgrid system has hierarchical control infrastructure in different levels similar to conventional grids. The microgrid requires enhanced control techniques to manage any level of system. Safe operation of microgrid in both operation modes and connection and disconnection between microgrid and utility grid are depended to microgrid control techniques. The controllers should ensure to operate the system regarding to predefined circumstances and efficiency requirements. The hierarchical control methods and applications of microgrid infrastructure are presented in the proposed chapter

Fractionation of graphene oxide single nano-sheets in water-glycerol solutions using gradient centrifugation

A centrifugation method for the separation and fractionation of graphene oxide (GO) single nano-sheets in the size range of 150-850 nm is reported. The measured electrophoretic mobility of the fractionated single sheets ranges from -0.2 to -1.4 μm cm/V·s where the interpreted zeta potentials vary from -3 mV to -17 mV with increasing sheet size. The single GO sheets show auto-fluorescence in the visible range of 350-650 nm using an excitation wavelength of 200 nm. Furthermore, the GO nano-sheets functionalized using PEG are found to be non-cytotoxic in in-vitro at concentrations up to 90 μg/ml, with a small reduction in cell viability -10%- at 260 μg/ml. The observed concentration-dependence of the cytotoxicity potentially explains the differing conclusions on cytotoxic potential reported in the literature. The GO nano-sheets therefore have the potential to be used as fluorescent drug delivery carriers of specific size

A Two-Loop Hybrid Method for Optimal Placement and Scheduling of Switched Capacitors in Distribution Networks

This paper presents a method to find the optimal size and place of the switched capacitors using a hybrid optimization algorithm. The objective function includes the active and reactive power of power plants, the capital and maintenance costs of capacitor banks, and the cost of active and reactive power losses in distribution lines and transformers. The impact of the load model on the optimal sizing and placement of switched capacitors is studied using three different scenarios: In the first scenario, all loads are voltage-dependent; in the second scenario, only a portion of loads are voltage-dependent; in the third scenario, all loads are voltage-independent. The proposed hybrid algorithm incorporates an outer and two inner optimization layers. The outer layer is executed by a genetic algorithm (GA), while the inner layer is performed by a GA, an exchange market algorithm (EMA), or a particle swarm optimization (PSO). The performance of GA-GA, GA-EMA, and GA-PSO hybrid schemes are compared on an IEEE 33-bus test system. Moreover, IEEE 33-bus and 69-bus networks are used to verify the effectiveness of proposed hybrid scheme against the gravitational search algorithm (GSA), a combination of PSO and GSA (PSOGSA), cuckoo search algorithm (CSA), teaching learning-based optimization (TLBO), and flower pollination algorithm (FPA). The results highlight the advantage of the proposed hybrid optimization scheme over the other optimization algorithms

Atorvastatin and prevention of contrast induced nephropathy following coronary angiography

Background: Contrast induced nephropathy (CIN) is one of the most common complications after radiographic procedures using intravascular radiocontrast media. The aim of the current study was to assess the effect of atorvastatin on prevention of CIN in patients undergoing coronary angiography. Materials and Methods: In a clinical trial study, 200 patients referred for angiography were randomly divided into two groups of using 80 mg atorvastatin and placebo before the procedure. Furthermore, 100 patients who were under chronic treatment of statins were included as the third group. Serum creatinine (Scr) levels before and after the procedure were evaluated and incidence of CIN (post-procedural Scr of >0.5 mg/dl or >25 from baseline) was assessed. Results: Mean age of the participants was 60.06 ± 0.69 years and 276 (92) were male. There were no significant differences between group with respect to age and gender. In pre-operation atorvastatin, placebo and long term statin groups, the incidence of CIN was 1, 2 and 1, and mean changes of Glomerular filtration rate (GFR) was 3.68 ± 1.32, �0.77 ± 1.21 and 1.37 ± 0.86; and mean changes of creatinine (Cr) was �0.05 ± 0.02, 0.02 ± 0.02 and �0.01 ± 0.01 respectively. respectively (P = 0.776, 0.026 and 0.041 respectively). In pre-operation atorvastatin group, Cr decreased, and GFR increased significantly (P = 0.019 and 0.007 respectively). Conclusion: pre-operation short term high dose atorvastatin use was associated with a significant decrease in serum Cr level and increase in GFR after angiography. © 2015, Isfahan University of Medical Sciences(IUMS). All rights reserved