Print ISSN: 1812-125X

Online ISSN: 2664-2530

Volume 25, Issue 3

Volume 25, Issue 3, Summer 2012, Page 1-208


Electrical Conductivity of Acetyl Acetonyl binylidene 5- Amino Salicylic Acid in Ethanol: Water Mixtures at Different Temperatures

Rana H. Al Hyali

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 1-18
DOI: 10.33899/edusj.2012.59198

ABSTRACT
The electrical conductivity of acetyl acetonyl binyledene 5- amino salicylic acid has been measured in (ethanol: water) mixtures at different percentage and different temperatures (283.16ºK - 313.16º K).
The results were analyzed by using Lee – Wheaton equation. The conductivity parameters, Λº (equivalent conductivity at infinite dilution, KA (association constant) and R (distance parameter between the ions) were calculated. From this study detail information about the conductivity parameters are interpreted Which have been effected by varying the temperatures. Thermodynamic parameters ∆ H, ∆G and ∆ S were also calculated.

Preparation and characterization of ionic complex salts based on benzotriazolium cations

Nabeel H. Buttrus; Heba A. Mohamed; F. T. Saeed

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 19-26
DOI: 10.33899/edusj.2012.59194

Abstract
Ionic liquid based on benzotriazolium ions were synthesized. these ionic liquids were characterized by IR, UV, Conductivity measurements and elemented analysis. There ionic salts with Co+2, Ni+2,Cu+2 and Zn+2 of

*correspondance authour
the types [A]+2[MCl2I2] and [A`]+ [MCl2I2], where A= benzotriazolium cation+1, A` = benzotriazolium cation+2, M = Co+2, Ni+2, Cu+2 and Zn+2 were prepared and characterized by elemental analysis, molar conductance, IR, UV∕V is, metal content and magnetic measurements. The results of electronic spectra and magnetic measurements showed that the anions of the type [MCl2I2] have tetrahedral and square planer geometry around the metal ions.

Determination of the lethal dose 50% (LD50) of cadmium chloride and the histopathological changes in male mice liver and kidneys

Talib Hussen Ali

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 27-38
DOI: 10.33899/edusj.2012.59200

ABSTRACT
The lethal dose 50 (LD50) test involves the administration of cadmium in the form of CdCl2 to group of animals at an increasing dose in order to determine the dose that kills 50 percent of the test mice within a set of time frame (24 and 48h).
The cadmium contents of liver and kidneys from dosed and control animals were determined by atomic absorption spectroscopy moreover, levels of alkaline phosphatase (ALP), in the target tissue were measured.. Male mice were dosed by 0.15ml cadmium (equivalent to the LD50 5.98 mg/kg body weight) in the form of CdCl2 via intraperitoneal injection for short-term treatment once per 24, 48 and 72h and, for long-term treatment once per week for 1, 4and 8 weeks then, sacrificed.
The results showed that the effect of short-term and long-term Cd-administration on hepatic and renal Cd accumulation in the Swiss mice was found to be time dependent fashion. Atomic absorption examination showed that the Cd-content in both liver and kidneys increased significantly time dependent by 98-145% in liver and 100-300% in kidney at short-term treatment whereas for long-term treatment this increasing were 143-173% in liver and 200-370% in kidney respectively.
This study also presents the histopathological effects in mice liver and kidney. Long-term Cd exposure produced damage to the entire kidney, including tubular degeneration, tubular cell apoptosis, interstitial inflammation and glomerular swelling and also resulted in liver injury including non-specific chronic inflammation and apoptosis, while it was less pronounced in short-term exposure.. Results of the biochemical profile indicated marked hepatic and renal toxic effect of cadmium reflected by the dramatic change in alkaline phosphatase (ALP) activity level, in the liver and kidney tissue. a significant increase (from100 to130%) in hepatic ALP activity, while the renal ALP activity level decreased by (from 95% to 65 %) as compared with those levels of the control in all relative periods of exposure.

Noise Figure Characteristics of Erbium Doped Fiber Amplifiers at single and multiple amplified stage

Ragheed M. Ibrahim; Nawzat S. Saadi; Saad F. Ramadhan

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 44-53
DOI: 10.33899/edusj.2012.59193

Abstract
In this study, an Erbium Doped Fiber Amplifier (EDFAs) simulation program has been written in Matlab to characterize Noise Figure variations of a forward pumped EDFAs operating in C band
(1525-1565 nm) as functions of Er3+ fiber length, injected pump power, signal input power and Er3+ doping density. The effect of multiple amplified stage on the noise figure was student at different Fiber length and pumping power. The numerical results shows that EDFAs could be operated in saturation regimes leading minimum noise figure when the EDFAs is supplied with sufficient pump power, Moreover a continuous increasing of the noise figure value was demonstrated by increasing all of amplified stage number and fiber length.

A Modified Globally Convergent Self-Scaling BFGS Algorithm for Unconstrained Optimization

Abbas Y. AL-Bayati; Basim A. Hassan; Sawsan S. Ismael

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 54-61
DOI: 10.33899/edusj.2012.59195

Abstract
In this paper, a modified globally convergent self-scaling BFGS algorithm for solving convex unconstrained optimization problems was investigated in which it employs exact line search strategy and the inverse Hessian matrix approximations were positive definite. Experimental results indicate that the new proposed algorithm was more efficient than the standard BFGS- algorithm.

The Diagonal Update for Unconstrained Optimization

Saad Shakir Mahmood; Ali Ibrahim Mansour; Haydir Ali Hassan

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 68-73
DOI: 10.33899/edusj.2012.59199

ABSTRACT
In this research we introduced a new update of the Hessian matrix or we updating only the diagonal elements of Hessian matrix, and make the non-diagonal elements always equal to zero and in this case we can preserve the sparse property so called the Diagonal Update.

Solving Infinite Nonlinear Boundary Value Problems of Three Orders by Using Shooting Method

Ahmed Antsar Ghatheth

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 74-81
DOI: 10.33899/edusj.2012.59189

ABSTRACT The purpose of this research is to design an algorithm for solving nonlinear boundary value problems of third orders with an infinite number of boundary conditions. Newton-Raphson method was used for finding (∞) value then we solved it by using shooting method. good results were obtained with a very small error value.
 

Performance Evaluation of MANET Routing Protocols for Varying Topologies Size

Awos Kh. Ali

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 82-94
DOI: 10.33899/edusj.2012.59192

ABSTRACT
Mobile ad-hoc network (MANET) is a collection of wireless mobile hosts forming a temporary network without the centralized administration or base station. Mobile ad-hoc network have the attributes such as wireless connection, continuously changing topology, ease of deployment. This study has compared the performance of two MANET routing protocol DSDV and TORA by using random mobility model. In this study two performance metrics have been chosen, such as Average Delay and throughput. The simulations are carried out on NS-2. The performance differentials are analyzed using varying network size (20 and 50 nodes) and simulation time was 100s. Simulation results confirm that DSDV performs well in terms of Average Delay. But TORA performs better than DSDV in terms of throughput and changing in network topology.

Constructing Reliable Skin Detector Based on Combining Texture and Color Features

Alaa Yaseen Taqa; Hamid A. Jalab

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 95-109
DOI: 10.33899/edusj.2012.59191

Abstract
Various approaches of skin detection have yet to demonstrate a stable state of performance. This is due to skin color in an image that is sensitive to variant illumination, camera adjustments, and human skin types. To contribute in overcome this problem a robust skin detection method that integrates both color and texture features is proposed. Texture features were estimated using statistical measures as range, standard deviation, and entropy. Back-propagation artificial neural network is then used to learn features and classify any given inputs. In this work, two skin detectors based on texture features only, and a combination of both color and texture features (proposed) have been constructed. Furthermore, the paper analyzes and compares the obtained results from the both skin detectors to show the impact of the integrating color and texture features to the robustness level. It found that the proposed skin detection method achieved a true positive rate of approximately 94.5% and a false positive rate of approximately 0.89%. Experimental results showed that proposed approach is more efficient compared with other state-of-the-art texture-based skin detector approaches.

Using Genetic Algorithm For Eye Location Detection

Ramadan M. Ramo

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 110-122
DOI: 10.33899/edusj.2012.59197

Abstract
In this research a hybrid system has been made to locate the position of eyes in the human face depending on the circular form of the eye. The primary process of image has been done using Gaussian Smoothing Operator to soften the image as well as to decrease the noise in it, then Sobel Operator has also been used to show the ridges. The suggested method is to hybridize the genetic algorithm (GA) together with Hough method to show the circle (CHT) which is recalled as (GCHT). This method has been applied on some models and the result shows that it has high accuracy and high performance in determining the eye position. The research is regarded as a primary level of recognition the for security purposes.

Preparation of some non-homogeneous cyclic compounds (pyrazolines and Isooxazolins)

Nem Salim

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 1-12
DOI: 10.33899/edusj.2012.59205

Abstract
In this paper number of some dichalcones (1-6) were prepared by reaction of one mole of acetone with two moles of benzaldehyde and benzaldehydes substituted (2-methoxy, 4-methoxy, 3,4-dimethoxy, 2-chloro and 4-nitro) in the presence of (10%) sodium hydroxide as a base. Pyrazolenes (7-12) were prepared from the reaction of dichalcones (1-6) with acetic hydrazide in the presence of (45%) sodium hydroxide as a base.
Isooxazoline (13-18) were prepared from the reaction of dichalcones (1-6) with hydroxyl amine hydrochloride in the presence of (10%) sodium hydroxide as a base. These compound were studied and identified by physical and spectral methods.

Study of some virulence factors of Salmonella typhi Pseudomonas aeruginosa, Micrococcus luteus and Staphylococcus aureus

Rana al-Sabawi

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 13-24
DOI: 10.33899/edusj.2012.59208

Abstract
This study includes the ability of the four types of bacteria to adhere to the surface of the mouth epithelial cells and the results showed a significant difference in the ability of adherence among the species.
The adherence on the epithelial cell is strong for Salmonella typhi and Pseudomonas aeruginosa, while the Staphylococcus aureus and Micrococcus luteus showed less ability of adhesion than the first two species.
Also, this study revealed the capability of Salmonella typhi and Pseudomonas aeruginosa to agglutinate all types of blood groups that used in the study, while the Staphylococcus aureus and Micrococcus luteus do not agglutinate any one of human blood groups.

Isolation and diagnosis of pathogenic bacteria from the intestine of carp (Cyprinus carpio) from Tigris River in the city of Mosul

Nawal Aziz Khalil Obeidi; Somaya Yasin Abdullah Al - Dabbagh

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 25-36
DOI: 10.33899/edusj.2012.59206

ABSTRACT
Eighty samples were collected from intestine of Cyprinus carpio fish from Tigres river passing through Mosul city during the period from October 2009 to October 2010.
In this study Intestinal samples of fish showed bacterial growth and yielded 74 isolates 92,5%, 56 isolates (70%) were found belong to eight genus of Gram-negative bacteria and 18 isolates (22.5%) of Gram-positive bacteria. They are 14 isolates (%17.5) Aeromonas hydrophilia, 13(%16.25) Pseudomonas aeruginosa, 12(%15) Esherichia coli, 6(%7.5) Klebsiella pneumonia, 5(%6.25) Enterobacter aerogenes, 3(%3.7) Citrobacter freundii, 1 (%1.25) Proteus spp. 2(%2.5) Flavobacterium spp. Gram positive included 5(%6.25) Staphylococcus spp. 4(%5) Enterococcus fecalis. 4(%5) Listeria spp., 3(%3.7) Bacillus spp., 2(%2.5) Corynebacterium spp.
The result of sensitivity test was variable. Most species of bacterial isolated were resistant to ampicillin but sensitive to ciprofloxacin other bacterial isolated give variable results between resistant and sensitiv to other types of antibiotic used in this study.

Anatomical histological and histochemical structure of the retina in Mabuya aurata lizard

Sanabel Al-Thanon

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 37-59
DOI: 10.33899/edusj.2012.59209

ABSTRACT
The present study carried out to explore the anatomical morphology and histological structure, as well as some histochiemical aspects of the retina in Mabuya aurata lizard which is a carnivorous animal. On the other hand to investigate the retinal specializations with respect to nutritional nature.
The result showed anatomically there was retinal thickness variation. The dorsal retina more thicker than the ventral one. On the other hand there was thickness variations in the same region (ventral or dorsal).
Histologically the retinal pigment epithelial cells appeared as low cuboidal cells with polyhedral shape in cross section and stained positively with Alacian blue PH=1.One type of rod and tow types of cones (single & double) were appeared. The cone ratio was 77% while the rod 13%.The density of rods and cones differ in the different parts of the retina. PAS stain showed the parabloid in the cone and oil droplet also appeared. The thickness of outer nuclear layer also varied. The distinct feature of the retina in this animal was the thickness of inner nuclear layer which also varied. The outer and inner plexiform layers also showed thickness variations. The interplexiform cells appeared in the inner plexiform layer which seldom appeared in the vertebrates. The ganglion cells organized in 1-6 rows, on the other hand the ganglion cells nuclei showed variation in shape, volume and stains affinity. No secondary papillae appeared in the visual disc.
The most important retinal specializations were the appearance of two foveae, the deep convexiclivate centrodorsal one and the 2 nd shallow concave dorsotemporal fovea, This is a seldom state in the lizards. The other specialization was the dorsal area centrales at which the retinal layers more thicker. The retina a vascular, but a highly vascular conus papillaris, which extend in the vitreous chamber, appeared. This structure restricted in the lizards only.
I can Conclude that in the M.aurata lizard there were a unique anatomical and histological features which indicate that this animal Posses visual a cuity, high resolution power and sensitivity. These features classify this lizard diurnal in activity, in contrast with most other lizards which are nocturnal.

Effect of alcohol on blood pressure, cholesterol and certain electrolytes concentration

Mahmud Ismail Mohamed Jubouri

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 60-68
DOI: 10.33899/edusj.2012.59214

Abstract
This study was conducted to determine the effect of alcohol on human health through measurement of some changes in physiology, biochemical and electrolytes in serum blood of alcohol addicts persons and these change include (blood pressure, cholesterol concentration, total & direct, conjection bilirubin, sodium concentration, potassium, calcium and chloride) for forty blood samples from normal and alcohol addicted healthy males then they compared with (20) blood samples of a non-alcoholic healthy persons as a control group.
Results showed increase in the percentage of these changes in serum blood of those persons account quantity of drink, attain increase percent in concentration of sodium (104.39, 104.02, 104.61 %) account quantity of drink (250, 500, 1000) but attain percent increase concentration of chloride (106.52،106.90, 101.82 %), but the increase percent in concentration of cholesterol (101.71, 101.14,100.9 %) while attain most those persons percent increase in blood pressure attain (63%).

Determination of fructose and some mineral elements concentration in the seminal plasma of rams

Anam Ahmed Hamza; sarab dawuwd sulayman; Mohammed Ahmed Hamza

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 69-77
DOI: 10.33899/edusj.2012.59203

Abstract
The study included determination of ram's semens concentration in 22 samples collected by using artificial vagina with averag of one ejaculate for aweak. The sperm concentration was (2x 109 /ml) and the percentage of life sperms obtained by using the eosin dye (85%) in addition to the use of Trypan blue to show the intact acrosome. The result showed the concentration of fructose in seminal plasma was (21± 6 mmol/ L) The study also included the measurement of the elements concentrations of (zinc, magnesium, calcium, sodium, potassium, and nickel) in ram seminal plasma and the result showed that the order of these concentrations of Na, k, Ca, Zn, Mg, Ni have been decreased respectivly. The presence of these elements in ram semen could have different rols to play in the survival and function of spermatozoa.

Studying the effect of sewage water irrigation on the mineral composition of Purslane plants

Farah Sobhi Saleh

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 78-92
DOI: 10.33899/edusj.2012.59211

ABSTRACT
Six sites of different farms in Mosul district (Sherikhan village, Shur valley, Aden, Al Atabaa, Jerf Al Malleh and Furgan areas) which Purslane plants in these farms were irrigated by Wells, sewage or industrial and domestic waste water. The results of this study showed that there was a significant increase in the four heavy metals Cd, Pb, Ni and Zn content of the irrigation water mainly in Shur valley water, in the other hand there was an increase in the soil and plant content of the heavy metals with a significant decrease in nutrient metal concentrations in the growing plants in Aden area, while there was a decrease in the heavy metal concentration in the soil and water, In addition there was a significant increase in nutrient metal concentration in the growing plants in Sherikhan village which were irrigated with wells water in comparison with the other sites of the study.

Production of cellulase enzyme from some local fungal isolates and the effect of some culture conditions

shamal Younis Abdel Hadi; Nour Amer Mohammed Ali; Bushra Essam Kamel

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 93-106
DOI: 10.33899/edusj.2012.59210

Abstract:
Ten local strains of fungi were isolated and identified. these fungi are belong to the following genera: Aspergillus niger, Alternaria alternata, Penicillium sp, Rhizopus sp, Rhizoctonia solani, Fusarium solani, Chaetomium sp, Macrophomina sp., Cladosporium sp. and Aspergillus flavus, isolated from the soil of Mosul University. The ability of isolated fungi to cellulase production in a solid media was investigated. A quantitative test using liquid media was used to determine the best effective isolate for cellulase production. determine A. niger gave the highest production of cellulase (8.12) unit/ml. Carboxymethyl cellulose as a carbon source gave highest production of cellulase (8.15) unit/ml. The best concentration of the carbon source was (12) gm/L which gave highest production of enzyme (8.67) unit/ml. The optimum temperature gave the highest production of cellulase (8.36) unit/ml was 30CO. The pH 5.5 considered as the optimum one for enzyme production, as it gave (9.22) unit/ml.

Study the electrical and optical characteristics of diode pumped solid state frequency doubled (DPSSFD) semiconductor laser

Musab Saleh Mohammed

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 107-119
DOI: 10.33899/edusj.2012.59217

Abstract:
The electrical and optical characteristics of diode pumped solid state frequency doubled (DPSSFD) semiconductor laser had been studied. Five different techniques had been used to calculate the laser threshold are (L-I, V-I, dV/dI vs I, IdV/dI vs I, L/(dL/dI) vs I). The calculated values of threshold current had been found varying from 96mA to 99mA.While the series resistance of the laser diode was determined above threshold by using three methods (V-I, dV/dI vs I, IdV/dI vs I) and the value estimated between (6.3 ~ 6.6). The quantum differential efficiency  D had been found to be high and equal to 0.66W/A. Maximum optical power emitted from DPSSFD laser is 14mW.The electrical ideality factor and optical ideality factor should be nearly equal and they are about unity.

Effect of laser pulse capacity (titanium-blue sapphire) on propagation properties in photonic crystal fibers

Marwan Hafeez Younis; Abdul Ghafoor Abdullah

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 120-135
DOI: 10.33899/edusj.2012.59215

Abstract:
Two designs of photonic crystal fibers with similar parameters are proposed, the difference only in the air fraction. The Air fraction of the PCF1 is 0.4, while for the second design is increased to 0.45. The propagation properties of the both designs are investigated. The results show that the zero dispersion wavelength (λZD) for PCF1 and PCF2 are pushed to the visible region far away from the 1.27µm as in traditional silica fibers.
The effect of the laser pulsed power of the (Ti-Sapphire) of 0.8µm on the dispersion profile of PCF1 and PCF2 is also studied. The λZD for the PCF1 is blue shifted, while a small increment in the air fraction as in PCF2 cause red shift for λZD. On the other hand, the sensitivity of the PCF2 for the pulse power (0.3nm/kW) is 10 times more comparing with the sensitivity (0.03nm/kW) of the PCF1.

Digital audio files reliability

Yassen Hikmat Ismail; Eman Fathi Ahmed

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 136-148
DOI: 10.33899/edusj.2012.59218

Abstract
Today the digital communication has become one of the most important things to the infrastructures in most applications, such as the Internet and in some cases which requiring confidential in communications that are confidential information become a sensitive issue. in this research we proposed a method to provide a way to achieve reliability in the digital audio files. Where we build a system to achieve the reliability of the digital audio through camouflage Uses one-way function and a summary of the message, as well as the idea of a digital signature.
Also we provide an efficient way to achieve the Digital Watermarking for digital audio. This research allows the recipient of the digital audio to ensure reliable voice and detect any possible change in the sound that occurs by any one during the sending over the computers network. We illustrate the results within the practical value of using the Matlab package ver. 7.0.

Extracting the features of English letters pronounciation using the fractal dimension

Maher Ahmed Anwar Al Naama

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 149-162
DOI: 10.33899/edusj.2012.59212

Abstract
Researches and techniques of pattern recognition aim at finding and developing techniques for recognizing certain patterns or structures in the digital signals. A signal can represent a sound segment or a verbal segment comprising a word or even a computer text.
This research aims building a system that works on extracting the features distinguishing English letters pronunciation through entering sound segments (26 sound segments each of which representing one of the English letters) to the computer. (WAV) extension files have been used because this type of files cannot be affected by compression process. Each sound segment enters primary processing. After that, the distinctive features of each sound segment are extracted through finding the value of fractal dimension, by using the 2-Dimension Variation Algorithm, then analyzing and studying the fractal dimension values resulting from each sound segment to recognize the pronunciation of the entered letter.
After, it has been shown that fractal dimension is a distinctive feature for pronouncing the entered English letters, and that using the 2-D Variation method for calculating fractal dimension yielded accurate results that comply with the research requirements.

Application of factor analysis and cluster analysis to the standard consumer prices in Iraq: a comparative study

Marwan Abdul Aziz Dabdoub; Nour Nozet Sayala

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 163-179
DOI: 10.33899/edusj.2012.59216

Abstract
Factor analysis may be considered as a classifier analysis and mostly does the same function as cluster analysis. Cluster analysis and factor analysis are applied to the standard prices of certain nine consumer goods during twelve months in 2005. The results concluded from both analyses are the same.

Alternative rational technique to compute multi-objective linear programming problems

Abbas Younis al-Bayati; Basim Abbas Hassan; baraat sulayman

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 180-190
DOI: 10.33899/edusj.2012.59204

Abstract
In this paper, we have been suggested an alterative rational technique to compute the value of the objective function of a multi-objective linear programming problems. Numerical results indicate that the efficiency of our proposed technique corresponding to standard Chandra Sen method is very effective according to a number of selected test problems.

minimal blocking set of size (30) in PG (2,19) plane

Amani Banyan Ibrahim Al-Salim

JOURNAL OF EDUCATION AND SCIENCE, Volume 25, Issue 3, Pages 191-205
DOI: 10.33899/edusj.2012.59202

Abstract
A blocking set B in projective plane PG(2,q) is a set of points such that every line in the plane intersect B in at least one point and there exist a line intersect B in only one point, we say that B is minimal if B has no blocking subset. In this research we proved the non_existence of minimal blocking set of size (30) contains 12_secant and not contains 13_secant in PG(2,19).