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Articles 6391 - 6420 of 6607
Full-Text Articles in Entire DC Network
Understanding Of Algebraic Notation And Its Relationship With Cognitive Development Among Form Four Students, Saw Hoon Ong
Understanding Of Algebraic Notation And Its Relationship With Cognitive Development Among Form Four Students, Saw Hoon Ong
Student Works (2000-2009)
This study attempts to identify the interpretation of letters used in algebraic expressions and equations by a sample of 139 Form Four students in an urban secondary school. It also determines the distribution of their levels of understanding of algebraic notation and their cognitive levels. It further investigates the relationship between the levels of understanding of algebraic notation and cognitive levels. To achieve these aims, two sets of instruments were used: the Algebra Test and the Longeot Reasoning Test. The findings of the study show that more than 80% of the students could successfu lly use the lower level of …
Kemahiran Berfikir Secara Kritis Dalam Pengajaran Sejarah : Perspektif Murid Tingkatan Empat Di Teluk Intan, Khairi Ariffin
Kemahiran Berfikir Secara Kritis Dalam Pengajaran Sejarah : Perspektif Murid Tingkatan Empat Di Teluk Intan, Khairi Ariffin
Student Works (2000-2009)
This research aimed at finding out form four students in Teluk Intan perspective towards the teaching of History in schools. The researcher focused on the aspect of the teachers' teaching styles, elements that were emphasized in the history teachers' teaching and their approaches in encouraging and developing critical thinking skills among students. Another three aspects analyzed were the teachers' emphasis on Bloom Taxonomy levels, the methods and approaches practised by the History teachers and the types of question emphasized in the teaching of History. Another purpose of this research is to find out whether students' achievements in the History subject …
Pengaruh Bahasa Dalam Pencapaian Matematik Di Sebuah Sekolah Persendirian Cina, Sook Theng Pang
Pengaruh Bahasa Dalam Pencapaian Matematik Di Sebuah Sekolah Persendirian Cina, Sook Theng Pang
Student Works (2000-2009)
The purpose of this study was to investigate the influence of language in mathematics achievement of Form Four students, and their difficulties in solving mathematics word problems in Bahasa Malaysia version. 40 Form Four students from one of the Chinese Independent High School in Kuala Lumpur, who speak Bahasa Malaysia as a second language were asked to solve 10 mathematics word problems in Bahasa Malaysia version in 40 minutes. Before that, they were asked to solve 10 mathematics word problems in Bahasa Cina version during their Final Year Examination (1999). After that, J samples were interviewed. The interviews conducted to …
Faculty Handbook, Georgia Southern University
Faculty Handbook, Georgia Southern University
Faculty Handbooks
Faculty Handbook for Georgia Southern University for the 2000-2001 academic year. The Faculty Handbook is published online by the Office of the Vice President for Academic Affairs and archived in Digital Commons@Georgia Southern.
Inclusive Production Of Π0, Η, Η′ (958), Kg0s And Λ In Two- And Three-Jet Events From Hadronic Z Decays, R. Barate, M. Thulasidas
Inclusive Production Of Π0, Η, Η′ (958), Kg0s And Λ In Two- And Three-Jet Events From Hadronic Z Decays, R. Barate, M. Thulasidas
Research Collection School Of Computing and Information Systems
The production rates and the inclusive cross sections of the isovector meson π0π0, the isoscalar mesons ηη and η′(958)η′(958), the strange meson K0SKS0 and the ΛΛ baryon have been measured as functions of scaled energy in hadronic events, two-jet events and each jet of three-jet events from hadronic Z decays and compared to Monte Carlo models. The analysis is based on 3.7 million hadronic events collected with the ALEPH detector at LEP at a centre-of-mass energy of s√=91.2s=91.2 GeV. The JETSET modelling of the gluon fragmentation into isoscalar mesons is found to be in agreement with the experimental results. HERWIG …
Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas
Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas
Research Collection School Of Computing and Information Systems
The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e+e−e+e− collisions at centre-of-mass energies from 130 to 183 GeV are presented. Results for e+e−e+e−, μ+μ−μ+μ−, τ+τ−τ+τ−, qq¯qq¯, bb¯bb¯ and cc¯cc¯ production show no significant deviation from the Standard Model predictions. This enables constraints to be set upon physics beyond the Standard Model such as four-fermion contact interactions, leptoquarks, Z′Z′ bosons and R-parity violating squarks and sneutrinos. Limits on the energy scale ΛΛ of e+e−ff¯e+e−ff¯ contact interactions are typically in the range from 2 to 10 TeV. Limits on R-parity violating sneutrinos reach masses of a few …
Undergraduate And Graduate Catalog [1999-2000], Georgia Southern University
Undergraduate And Graduate Catalog [1999-2000], Georgia Southern University
Undergraduate & Graduate Catalogs
No abstract provided.
Concert Recording 2000-04-26a, W. Dale Warren, Russell Pettitt, Brett Lawson, University Of Arkansas, Fayetteville. Concert Band
Concert Recording 2000-04-26a, W. Dale Warren, Russell Pettitt, Brett Lawson, University Of Arkansas, Fayetteville. Concert Band
Concert Recordings & Programs
National emblem march / E.E. Bagley -- Shenandoah / Frank Ticheli -- For the new day arisen / Steven Barton -- Prairie songs / Pierre La Plante -- Ave Maria / Franz Biebl -- Rikudim / Jan Van der Roost
Time Perception In Children With Attention Deficit Hyperactivity Disorder, Shawn Lee Fleck
Time Perception In Children With Attention Deficit Hyperactivity Disorder, Shawn Lee Fleck
All-Inclusive List of Electronic Theses and Dissertations
This study examines the relationship between time perception and working memory in 14 children with ADHD and 19 children without ADHD. The children were assessed in a university clinic using rigorous diagnostic criteria and procedures. Three licensed psychologists based their diagnosis on numerous assessment measures. Time perception of the children was assessed using a computerized, prospective time reproduction task. Working memory was assessed using a standardized measure of working memory. Children in the matched group reproduced the 60-second trial with significantly greater accuracy and produced significantly greater scores on the measure of working memory than the children with ADHD. These …
Properties Of Electrodeposited Cadmium Sulfide Films For Photovoltaic Devices With Comparison To Cds Films Prepared By Other Methods, Fi̇gen Kadirgan, Duli Mao, Wenjie Song, Tim Ohno, Brian Mccandless
Properties Of Electrodeposited Cadmium Sulfide Films For Photovoltaic Devices With Comparison To Cds Films Prepared By Other Methods, Fi̇gen Kadirgan, Duli Mao, Wenjie Song, Tim Ohno, Brian Mccandless
Turkish Journal of Chemistry
Films of CdS for photovoltaic devices were electrochemically deposited on tin oxide coated glass substrates at different conditions. The films were found to be smooth and uniform with a small grain size. X-ray diffraction measurement and analysis indicated a hexagonal phase rather than the cubic phase. The surface composition of the films was investigated by Auger Spectroscopy. Electrochemical deposition parameters were studied to obtain the optimum conditions for the best CdS films. Our films are compared from the pinhole number and particulate point of view with the films prepared by other methods.
Photochemical Processes And Accumulation Of Solar Energy In Oil Luminophors, A. P. Mamedov, M. I. Rustamov, R. A. Dzhafarova, Ch. K. Salmanova
Photochemical Processes And Accumulation Of Solar Energy In Oil Luminophors, A. P. Mamedov, M. I. Rustamov, R. A. Dzhafarova, Ch. K. Salmanova
Turkish Journal of Chemistry
Using the methods of absorption spectroscopy, luminescence and EPR there has been studied the mechanism of solar energy accumulation by high boiling products of oil refining and by luminophors prepared on their basis within wide temperature range (77-550 K). The photochemical processes with participation of all main components of oil products and luminophors have been considered. The mechanisms of accumulation of solar energy of the studied products and luminophors have been considered. The mechanism of accumulation of solar energy of the studied products prior and above their pour points have been found to differ significantly. The light energy accumulation and …
Auxiliary Controlled Intramolecular 1,3-Dipolar Cycloaddition Reactions Of Chiral Azomethine Ylides, Özdemi̇r Doğan, Philip P. Garner
Auxiliary Controlled Intramolecular 1,3-Dipolar Cycloaddition Reactions Of Chiral Azomethine Ylides, Özdemi̇r Doğan, Philip P. Garner
Turkish Journal of Chemistry
Intramolecular 1,3-dipolar cycloaddition reactions of chiral azomethine ylides obtained by thermal ring opening of chiral aziridines 7a, b and 8a, b are investigated. Synthesis of these aziridines 7a, b and 8a, b is described.
Synthesis And Reactivity Of Some Mannich Bases. Vi. New Arylamine Mannich Bases Derived From 2-Hydroxy-5-Methylacetophenone, Gheorghe Roman, Diana Nanu, Eugenia Comanita, Bogdan Comanita
Synthesis And Reactivity Of Some Mannich Bases. Vi. New Arylamine Mannich Bases Derived From 2-Hydroxy-5-Methylacetophenone, Gheorghe Roman, Diana Nanu, Eugenia Comanita, Bogdan Comanita
Turkish Journal of Chemistry
The amine exchange reaction has been applied for obtaining a new series of arylamine Mannich bases from variously substituted aromatic amines and 3-(dimethylamino)-1-(2'-hydroxy-5'-methylphenyl) propan-1-one. The structures of the newly synthesised Mannich bases have been investigated by IR, ^1H- and ^{13}C-NMR and shown to be in good agreement with the proposed ones.
Synthesis Of 4-Benzyl-1-Piperazineglyoxime And Its Use In The Spectrophotometric Determination Of Nickel, Mustafa Maci̇t, Hümeyra Bati, Beki̇r Bati
Synthesis Of 4-Benzyl-1-Piperazineglyoxime And Its Use In The Spectrophotometric Determination Of Nickel, Mustafa Maci̇t, Hümeyra Bati, Beki̇r Bati
Turkish Journal of Chemistry
A new reagent, 4-benzyl-1-piperazineglyoxime(BPGH_2), was synthesized and used for developing a simple and rapid extractive method for the spectrophotometric determination of nickel. This method is based on the selective extraction of nickel complex from aqueous solution into carbontetrachloride and the measurement of the absorption at 267 nm. The method was applied to the determination of nickel ion in some standard and practical samples.
Specific Determination Of Hydrogen Peroxide With A Catalase Biosensor Based On Mercury Thin Film Electrodes, F. Ni̇l Ertaş, Suna Ti̇mur, Erol Akyilmaz, Erhan Di̇nçkaya
Specific Determination Of Hydrogen Peroxide With A Catalase Biosensor Based On Mercury Thin Film Electrodes, F. Ni̇l Ertaş, Suna Ti̇mur, Erol Akyilmaz, Erhan Di̇nçkaya
Turkish Journal of Chemistry
A biosensor for specific determination of hydrogen peroxide was developed using catalase (EC 1.11.1.6) in combination with a mercury film electrode. Catalase was immobilized with gelatine by means of glutaraldehyde on the electrode surface. The biosensor response was monitored by following the reduction peak of dissolved oxygen at around -0.24 V. The peak current changes upon addition of hydrogen peroxide and gives a linear response in a concentration range of 1-50 x 10^{-6} M within a response time of 3 minutes.
The Synthesis Of Manganese(Iii) Acetate In Bipolar Packed-Bed And Trickle-Bed Electrode Cells, Altan Güvenç, Belgi̇n Karabacakoğlu, Ö. Mete Koçkar, A. Tarik Pekel
The Synthesis Of Manganese(Iii) Acetate In Bipolar Packed-Bed And Trickle-Bed Electrode Cells, Altan Güvenç, Belgi̇n Karabacakoğlu, Ö. Mete Koçkar, A. Tarik Pekel
Turkish Journal of Chemistry
In this research, the electrochemical oxidation of Mn(II) acetate to Mn(III) acetate was investigated in aqueous acetic acid solution, using a bipolar particulate electrode cell. In order to determine the effect of flow modes on the yield of Mn(III) acetate, which is an important oxidizing agent and catalyst in organic reactions, a bipolar particulate electrode cell was employed both in flooded and trickle flow modes. The experiments were conducted at controlled potentials of 50-250 volts using the solution (10% H_2O, 90% CH_3COOH, 0.1 M Mn(CH_3COO)_2.4H_2O, 0.1 M CH_3COONa.3H_2O) and at an optimum flow rate of 0.04 ml.s^{-1}. The values of …
Some Properties Of Cu, Zn-Superoxide Dismutase From Sheep Erythrocyte, Leman Tarhan, M. Nalan Tüzmen
Some Properties Of Cu, Zn-Superoxide Dismutase From Sheep Erythrocyte, Leman Tarhan, M. Nalan Tüzmen
Turkish Journal of Chemistry
Superoxide dismutase (SOD) was isolated from sheep erythrocyte. SOD activity was measured under the optimized assay conditions by observing the variations of autoxidation rate of 6-hydroxydopamine (6-OHDA). The enzyme was characterized as containing copper and zinc and was insensitive to chloroform-ethanol mixture but inhibited by cyanide and hydrogen peroxide. The activity variations and stability properties of sheep erythrocyte Cu, Zn-SOD were investigated under the optimized activity assay conditions by observing inhibition change at the autoxidation rate of 6-OHDA. The optimum pH and temperature of sheep erythrocyte Cu, Zn-SOD were found to be 9.4 and 30$^{\circ}$C respectively. The enzyme showed high …
Effect Of Non-Ionic Reagent Adsorption On Zeta Potential Of Fine Coal Particles, Zeki̇ Aktaş
Effect Of Non-Ionic Reagent Adsorption On Zeta Potential Of Fine Coal Particles, Zeki̇ Aktaş
Turkish Journal of Chemistry
The -5 \mum size fractions of two low rank British coals were used in zeta potential measurements. The electrophoretic behaviour was described by the Helmholtz-Smoluchowski equation. The non-ionic reagents used for the adsorption tests were of diacetone alcohol and 2-ethyl hexanol. Zeta potentials of both coals at various pHs were significantly different in the absence of the non-ionic reagents. Negligible variations were observed on the zeta potential curves of both coal particles in the presence of the non-ionic reagents used. It was concluded that the pH of coal particles in slurry is a principle parameter controlling the value of zeta …
Magnitudes Of Back Diffusion During Long-Term Diffusive Sampling Of Volatile Organic Compounds Using Carbotrap And Chromosorb 106, Naci̇ye Kiliç, James A. Ballantine
Magnitudes Of Back Diffusion During Long-Term Diffusive Sampling Of Volatile Organic Compounds Using Carbotrap And Chromosorb 106, Naci̇ye Kiliç, James A. Ballantine
Turkish Journal of Chemistry
The aim of the research was to investigate the magnitudes of the losses of some volatile organic compounds from the solid adsorbents, Carbotrap and Chromosorb 106 due to back diffusion during long-term diffusive sampling of volatile organic compounds in the environment. Experiments were performed by loading the compounds to be tested on the adsorbent tubes and leaving them in an outdoor environment to simulate the real life sampling conditions over a 14 day period. The losses due to back diffusion were investigated for both the high and the low initial concentrations of the fourteen compounds covering a wide range of …
An Efficient Synthesis Of (1 S , 2 R )-1-Amino-2-Indanol, A Key Intermediate Of Hiv Protease Inhibitor, Indinavir, Ayhan S. Demi̇r, Hi̇lal Aksoy-Cam, Nuretti̇n Camketen, Haluk Hamamci, Fatoş Doğanel
An Efficient Synthesis Of (1 S , 2 R )-1-Amino-2-Indanol, A Key Intermediate Of Hiv Protease Inhibitor, Indinavir, Ayhan S. Demi̇r, Hi̇lal Aksoy-Cam, Nuretti̇n Camketen, Haluk Hamamci, Fatoş Doğanel
Turkish Journal of Chemistry
(1S,2R)-1-amino-2-indanol, a key component of an HIV protease inhibitor is synthesized in four steps starting from indanone. The Mn(OAC)_3 mediated acetoxylation of indanone followed by fungus catalyzed hydrolysis of acetoxyindanone furnished optically pure \alpha-hydroxy indanone. Formation and enantioselective reduction of oxime ether of 2-hydroxyindanone afforded (1S, 2R)-1-amino-2-indanol in 97% {\it cis} selectivity.
Swelling Behavior Of Acrylamide-2-Hydroxyethyl Methacrylate Hydrogels, Belma Işik Yürüksoy
Swelling Behavior Of Acrylamide-2-Hydroxyethyl Methacrylate Hydrogels, Belma Işik Yürüksoy
Turkish Journal of Chemistry
In this study, hydrogels of poly(acrylamide-co-2-hydroxyethyl methacrylate) having different properties were prepared by a redox polymerization method. Poly(ethylene glycol), PEG 4000 was included in the polymerization recipe to increase the microporosity of the resultant polymeric structures. AAm/HEMA hydrogels with different properties were obtained by changing initial AAm/HEMA mole ratio, total monomer, PEG 4000 and crosslinker concentrations.
Solvent Extraction Of Fe^{3+} Cation By Diazo-Coupling Calix[4]Arenes, Hasaletti̇n Deli̇göz, Emi̇n Erdem, Hasan Kocaokutgen
Solvent Extraction Of Fe^{3+} Cation By Diazo-Coupling Calix[4]Arenes, Hasaletti̇n Deli̇göz, Emi̇n Erdem, Hasan Kocaokutgen
Turkish Journal of Chemistry
The solvent extraction of Fe^{3+} cations from the aqueous to the organic (chloroform) phase was carried out using p-tert-butyl calix[4]arene(\underline{1}), calix[4]arene(\underline{2}), diazo-coupling calix[4]arenes [p-(4-n-butyl-phenylazo)calix[4]arene (\underline{3}), p-(4-phenylazophenylazo)calix[4]arene(\underline{4}), p-(4-acetanilidazo)calix[4]arene(\underline{5}), p-(N'-2-thyazol-2ylsulphanylazo)calix[4]arene(\underline{6}) and p-(2-thyazolazo)calix[4]arene(\underline{8}) and the derivatives of phenol [2-(5-bromo-2-pyridylazo)-5-diethylaminophenol(\underline{8}) (Bromo-PADAP) and 2-hydroxy-5-methyl\-phenylazonapthol(\underline{9}) (HMPAN)]. It was found that the compounds (\underline{1}-\underline{9}) showed the highest extractability toward Fe^{3+} at pH 4.5-5.4 Compound \underline{5} shows strong binding ability to Fe^{3+} ion. Based on the method of continuous variation, calixarene \underline{5} formed a 1:1 complex with Fe^{3+} ion.
Preparation Of Optically Active Amino Acid Derivatives Of Some Methylated 5-Amino-Azaheterocycles, Mashooda Hasan, Farzana Shaheen, Uzma Yunus, Shazia Munir
Preparation Of Optically Active Amino Acid Derivatives Of Some Methylated 5-Amino-Azaheterocycles, Mashooda Hasan, Farzana Shaheen, Uzma Yunus, Shazia Munir
Turkish Journal of Chemistry
The present paper describes the reduction of 1-methyl-5-nitro-benzimidazoles ({\bf 1A, 2A}) and 1,3-dimethyl-2H-5-nitro-benzimidazol-2-one ({\bf 3}) to 5-aminobenzimidazoles ({\bf 4A, 5A}) and 1,3-dimethyl-2H-5-amino-benzimidazol-2-one ({\bf 6}) respectively with hydrazine hydrate in absolute ethanol in the presence of graphite. Compounds {\bf 5A} and {\bf 6} were converted to 2-ethyl-5-(phthaloyl-L-phenylalanyl)amino-1-methylbenzimidazole ({\bf 7}) and 1,3-dimethyl-5-(phthaloyl-L-phenylalanyl)aminobenzimidazol-2-one ({\bf 8}). Characterization of the synthesized compounds was done with the help of mass spectrometry and ^1H NMR spectroscopic studies. Optical activity of the amino acid derivatives {\bf 7} and {\bf 8} was also recorded.
X-Ray Diffraction Study Of Heat-Treated Graphitized And Ungraphitized Carbon, Rizwan Hussain, Riaz Qadeer, Mahmood Ahmad, M. Saleem
X-Ray Diffraction Study Of Heat-Treated Graphitized And Ungraphitized Carbon, Rizwan Hussain, Riaz Qadeer, Mahmood Ahmad, M. Saleem
Turkish Journal of Chemistry
Heat treatment of graphitized and ungraphitized carbon samples was carried out in air and argon atmosphere from ambient temperature to 700$^{\circ}$C. The changes in degree of amorphousness, mean crystallite size and interlayer separations were studied employing x-ray diffraction. The results revealed an increase in crystallinity when graphitized carbon was heated to 100 ^oC and above. This enhanced degree of arrangement is indicative of the removal of residual impurities entrapped during the production processes. In ungraphitized carbon, the transition from amorphous to crystalline character was not observed upon heat treatment.
Stereoselective Synthesis Of Butenolide And Butyrolactone Derivatives, Abdulkadi̇r Sirit
Stereoselective Synthesis Of Butenolide And Butyrolactone Derivatives, Abdulkadi̇r Sirit
Turkish Journal of Chemistry
Optically active butenolide and $\gamma$-butyrolactone derivatives were prepared by removing (R)-phenyl glycinol and (1R, 2R)-norpseudoephedrine used as chiral auxiliaries from butenolides and \gamma-butyrolactones in two steps. The structures of these products were determined using ^1H NMR, ^{13}C NMR, Mass spect., IR and microanalysis.
Heavy Metal Removal From Aquatic Systems By Northern Anatolian Smectites, Çi̇ğdem Arpa, Ridvan Say, Nuray Şatiroğlu, Sema Bektaş, Yuda Yürüm, Ömer Genç
Heavy Metal Removal From Aquatic Systems By Northern Anatolian Smectites, Çi̇ğdem Arpa, Ridvan Say, Nuray Şatiroğlu, Sema Bektaş, Yuda Yürüm, Ömer Genç
Turkish Journal of Chemistry
Competitive adsorption of the heavy metal ions Cu(II), Cd(II) and Pb(II) from aqueous media onto northern Anatolian smectites with a mean particle diameter of 200 $\mu$m, was investigated. The adsorption rate and capacity of the smectite for the selected heavy metal ions, containing different amounts of these ions (5-900 mg/L) at values ranging from pH 1.0 to 7.0 were studied. Very high adsorptions rates were observed at the beginning, and adsorption equilibria were then gradually achieved in about 30 minutes. The maximum adsorption of metal ions onto the smectite were found to be 41.46 mg Cd(II), 36.11 mg Pb(II) and …
Spectroscopic Studies Of Charge-Transfer Complexes Of 2,3-Dichloro-5,6-Dicyano-P-Benzo-Quinone, M. S. Subhani̇, N. K. Bhatti̇, M. Mohammad, A. Y. Khan
Spectroscopic Studies Of Charge-Transfer Complexes Of 2,3-Dichloro-5,6-Dicyano-P-Benzo-Quinone, M. S. Subhani̇, N. K. Bhatti̇, M. Mohammad, A. Y. Khan
Turkish Journal of Chemistry
Charge-transfer complexes of 2,3-dichloro-5, 6-dicyano-p-benzoquinone (DDQ) p-acetotoluidide, acetanilid, biphenyl and naphthalene were studied and their absorption spectra in solution were recorded. Absorption spectral data were obtained in CH_2Cl_2, CHCl_3, CCl_4 and mixture (CH_2Cl_2 + V) at different temperatures. Two charge-transfer bands were observed in each case. Spectral characterization of these complexes was determined and correlated with the ionization potential of the donor. Variation in thermodynamic parameters were also found to be due to change in donor and solvent.
Atmospheric Deposition Of Pb, Zn, Cu, And Cd In Amman, Jordan, Kamal A. Momani, Anwar G. Jiries, Qasem M. Jaradat
Atmospheric Deposition Of Pb, Zn, Cu, And Cd In Amman, Jordan, Kamal A. Momani, Anwar G. Jiries, Qasem M. Jaradat
Turkish Journal of Chemistry
Atmospheric samples were collected using a low-volume air sampler and dustfall containers during the summer of 1995 at different sites in the city of Amman, Jordan. The heavy metal contents in settleable particles (dustfall) as well as in air particulates (suspended) were analyzed by graphite furnace atomic absorbation spectrophotometry. The atmospheric concentrations of Zn, Cu, Pb, and Cd were 344, 170, 291, and 3.8 ng/m$^3$, respectively. The levels of these elements in the dustfall deposition were 505, 94, 74 and 3.1 $\mu$g/g, respectively. The fluxes and dry deposition velocities of these heavy metals were determined and compared with the findings …