THE STABILITY OF THE ACHIEVEMENT MOTIVE STRUCTURE AND ITS OPERATIONALIZATION WITH THE SCALE MOP2002

The objective of this paper is to test the stability of construct characteristics and the factorial structure of the achievement motive and the psychometrical characteristics of the instrument MOP 2002. The analyses are performed on the sample comprising 2846 examinees of different gender and of different educational profile. The sample has been collected during the period of 15 years in a transitional social context. The instrument MOP 2002 is applied, it contains 55 items and has a form of five-level scale. The results of factor analysis have shown that the instrument is multi-dimensional and consist of four factors: competing with others, persistence in realizing goals, realizing goals as source of satisfaction and orientation towards planning. All of these factors are, among others, important for successful participation in the competitive sport. By factor analysis of the second order it is established that the instrument has a unique object of measuring and satisfactory psychometrical characteristics proven stable during 15 years of application on heterogeneous samples of examinees

Motor oil effects on characteristics of engine

Over the last decades there has been more and more severe requirements set to producers of motor vehicles and lubricants. Beside the fact they should provide functional, reliable and permanent operation, a vehicle as a whole is expected to give an adequate answer to wider and various market requirements in terms of environmental protection, improvement of vehicle performance, reduction of fuel consumption and increased traffic safety. When it comes to requirements related to lubricant characteristics, ways of use and intervals in which their replacement should take place, they are becoming more severe, since the motor vehicles' constructors keep making new and harder conditions in reference with performance improvement and lubricant efficiency. This paper describes the results of motor oil quality measurements in relation with exterior speed characteristics of engine as well as the testing programme for oil in the engine on motor brake. The evaluation of motor oil quality is monitored by measuring sediments in vital parts of engine on one hand, and on the other, by measuring output characteristics of engine

Motor oil effects on characteristics of engine

Over the last decades there has been more and more severe requirements set to producers of motor vehicles and lubricants. Beside the fact they should provide functional, reliable and permanent operation, a vehicle as a whole is expected to give an adequate answer to wider and various market requirements in terms of environmental protection, improvement of vehicle performance, reduction of fuel consumption and increased traffic safety. When it comes to requirements related to lubricant characteristics, ways of use and intervals in which their replacement should take place, they are becoming more severe, since the motor vehicles' constructors keep making new and harder conditions in reference with performance improvement and lubricant efficiency. This paper describes the results of motor oil quality measurements in relation with exterior speed characteristics of engine as well as the testing programme for oil in the engine on motor brake. The evaluation of motor oil quality is monitored by measuring sediments in vital parts of engine on one hand, and on the other, by measuring output characteristics of engine

Promene krivine vratne kičme i morfologije cervikalnih pršljenova u različitim uzrastima i mogućnost procene skeletne zrelosti

Introduction During growth, proportions of craniofacial and cervical structures are changed. Craniofacial and cervicovertebral structures are morphologically and functionally connected, but their each other's influence is still unknown. Objective The aim of this study was to determine the changes in cervical lordosis and cervicovertebral morphology in different age periods and the possibility of estimating skeletal maturity, based on the percentage of anterior cervical vertebrae body height sum in the total anterior C2-C5 height. Methods The study included lateral radiographs of 120 patients of both sexes, divided into three different age groups: eight, 12-13 and 17-18 years of age. Five craniofacial and 15 cervical parameters were measured and analyzed. Results The results showed significant correlation between cervical lordosis angle and age, gender, anterior and posterior body height of C3, C4, C5, anterior C4-C5 and posterior C2-C3, C3-C4, C4-C5 intervertebral space, anterior body height of C2-C5. Overall values of all cervical body heights were more present in the total height of the spine in females, while all intervertebral spaces were more present in males. The percentage of anterior and posterior C2, C3, C4, C5 body height sum compared to total C2-C5 height increases with age. Conclusion The cervical lordosis becomes more curved and vertebral bodies occupy more space in females, while intervertebral spaces occupy more in males. Skeletal maturity could be estimated following vertebral percentage distribution in the total anterior C2-C5 part.Uvod Tokom rasta proporcije kraniofacijalnih i cervikovertebralnih struktura se menjaju. Ove strukture su morfološki i funkcionalno povezane, ali je njihov međusobni uticaj i dalje nepoznat. Cilj rada Cilj ove studije je bio da se uoče promene krivine vratne kičme i morfologije vratnih pršljenova u različitim uzrasnim grupama, kao i mogućnost procene skeletne zrelosti zasnovane na procentualnoj zastupljenosti zbira prednjih visina vratnih pršljenova C2, C3, C4 i C5 u ukupnoj dužini prednje visine kičme od C2 do C5. Metode rada Studija je obuhvatila 120 ispitanika oba pola koji su svrstani u tri starosne grupe: 8, 12-13 i 17-18 godina. Pet kranijalnih i 15 cervikalnih parametara je mereno i analizirano. Rezultati Rezultati su pokazali statistički značajnu korelaciju između zakrivljenosti vratne kičme i godina, pola, prednje i zadnje visine tela pršljena C2, C3, C4, prednjeg C4-C5 i zadnjeg C2-C3, C3-C4, C4-C5 međupršljenskog prostora. Prosečne vrednosti visine tela vratnih pršljenova procentualno su bile češće kod ispitanica, a svi međupršljenski prostori kod osoba muškog pola. Procenat zbira prednje i zadnje visine pršljena C2, C3, C4 i C5 povećavao se sa godinama. Zaključak Krivina vratne kičme postaje zakrivljenija i tela pršljenova zauzimaju više prostora kod žena, a međupršljenski prostor više kod muškaraca. Procena skeletne zrelosti bi mogla da se prati na osnovu procentualne zastupljenosti visine tela pršljena u ukupnoj dužini prednjeg dela kičme (C2-C5)

Orthodontic treatment of nongrowing patient with class II division 2 malocclusion by Herbst appliance

Background. Inheritance is most casual etiological factor of Class II division 2 malocclusion. This kind of malocclusion is very difficult for treatment specially in older patients. Case report. In the female patient, 20 years old, at the beginning of the treatment at the School of Dentistry in Belgrade, lateral cephalogram showed skeletal and dentoalveolar Class II division 2 malocclusion. She was in the Herbst treatment for 8 months and 12 months more with a fixed multibracket appliance. The measurements were performed on lateral cephalograms before and after the treatment: ii, is, mi, ms, Pg and ss. The distance from these points to occlusal perpendicular line (Olp) were measured and compared from cephalogram before to cephalogram after the treatment. Temporomandibular joint (TMJ) tomograms were compared from before and after the treatment by superimposition. Correction was found in molar and incisor relation, overjet and overbite. There were found sagital skeletal changes and soft tissue profile improvement. Conclusion. Herbst appliance is effective in the treatment of Class II malocclusions, even in adult patients. Dental and skeletal changes as a result of Herbst treatment could be good choice instead of camouflage orthodontics or surgical decision

Fuzzy pogled na životno okruženje

A period of fifty years has been reached since the introduction of the first applications based upon geographical information systems (GIS). GIS has not only influenced the development of methods, collection techniques, processing, manipulation and visualization of spatial data. It influenced also the expansion of scientific research in geosciences, as well as the technical disciplines that are engaged in spatial analysis. Nowadays, GIS is becoming the tool for verification and practical implementation of models and algorithms that have been developed within the frame of basic scientific disciplines. The meaning of the GIS acronym is becoming more and more related to term of Geographical or Geo Information Sciences. Scientific concepts that are increasingly applied in GIS are more emphasized in that way. GIS computational techniques, required also the development of geographical data models that should effectively support GIS operations. These models represent formal equivalents of conceptual models used by people in observing geographic phenomena. Spatial phenomena used to be mapped as clearly defined points with known coordinates, or as lines which connect the very same points, or as polygons with exactly defined borders. They were mapped previously in analog form and nowadays in digital format. This approach of perceiving a space, data analyses and visualization of spatial quires is limited on the application of basic rules of Boolean algebra and binary logic, with final results presented as classical thematic maps. The need for a mathematical model that would describe uncertainty of spatial data, resulted in the introduction of the theory of fuzzy sets in spatial analysis. Moreover, this model will provide a solution for visualization and grouping up of spatial phenomena in classes which do not have clearly defined borders.Primena tehnologija Geografskih Informacionih Sistema (GIS) otvorila nove pristupe i metodologije u analizama prostornih podataka. Narastajuće potrebe za prostornim podacima i efikasnijim sredstvima za njihovu analizu mogu se zadovoljiti primenom geoinformatičkih tehnologija. Uporedo sa razvojem GIS-a, posebno u zadnjoj deceniji dvadesetog veka i početkom novog milenijuma, svedoci smo i ekspanzije tehnologija koje se bave prikupljanjem i transferom prostornih podatka. To je rezultovalo povećanjem obima dostupnih podataka ali i svesti o potrebi za kritičkim sagledavanjem kvaliteta podataka, pouzdanosti i ocene pogodnosti za upotrebu u specifičnim aplikacijama. To je dovelo i do promenama u konceptu sagledavanja i apstrakcije prostora, a s time i novim pristupima u geoprocesiranju prostornih podataka, vizuelizaciji rezultata prostornih analiza

Dentoalveolarni terapijski efekti Herbst aparata i aktivatora kod osoba u postpubertetskom uzrastu sa malokluzijom klase II/1

Background/Aim. Functional appliances can be used effectively in the treatment of skeletal Class II/1 malocclusions. The best treatment results are obtained during active period of facial growth when skeletal, as well as dentoalveolar, changes occur. In comparison with removable functional appliances, such as activator, that are effective only during adolescent period of growth, the Herbst fixed appliance is also successful at the end of the growth period. It also offers a shorter treatment time and a patient compliance is not necessary. The aim of this study was to analyze and compare dentoalveolar changes in the group of young adult patients with Class II/1 malocclusion treated with the Herbst appliance and an activator. Methods. The sample for this study consisted of 50 patients of both sexes, 14-21 years of age with Class II/1 malocclusion. For estimating the effect of functional appliances used, the following cephalometrics parameters were determined: inclination of the upper and lower incisors, interincisal angle, antero-posterior molars relationships, overjet and overbite. The results obtained were statistically tested. Results. The cephalometric findings after the treatment indicated retroinclination of upper incisors (average value of 9°) and proclination of lower incisors (average value of 7°), mostly expressed in the patients treated by Herbst appliance (p lt 0.001). Increased overjet and distocclusion were completely corrected in the group of patients treated with the Herbst appliance, while the correction of malocclusion in the activator group was only partially accomplished. No changes in the overbite were noticed at the end of the treatment in both groups. Conclusion. The results of this study revealed that the Herbst appliance is more effective in the treatment of Class II/1 malocclusion in young adults in comparison with the activator.Uvod/Cilj. Funkcionalni aparati uspešno se koriste u terapiji malokluzija klase II/1. Najbolji rezultati postižu se terapijom u periodu pubertetskog skoka rasta, kada su moguća najveća skeletna i dentoalveolarna pomeranja. U poređenju sa terapijom pokretnim funkcionalnim aparatima, kao što je aktivator prema Andresen-u, terapija Herbst-ovim fiksnim aparatom (Herbst aparat), uspešna je i nakon pubertetskog skoka rasta, vreme terapije je kraće, a bolesnike ne treba motivisati za saradnju jer je aparat fiksiran na zubima. Cilj istraživnja bio je da se kod bolesnika mlađeg odraslog uzrasta sa malokluzijom klase II odeljenja 1 uporede efekti fiksnog funkcionalnog Herbst aparata i pokretnog aktivatora na dentoalveolarne strukture. Metode. Ispitivanje je obuhvatilo 50 bolesnika sa malokluzijom klase II/1, oba pola, uzrasta 14-21 godine. Efekti primenjenih funkcionalnih aparata, aktivatora prema Andresen-u i Herbst aparata, procenjivani su na osnovu parametara merenih na profilnim telerendgenskim snimcima, nagiba gornjih i donjih sekutića, interincizalnog ugla, okluzije po Angle-u, incizalnog stepenika i incizalnog preklopa. Dobijeni rezultati obrađeni su statistički. Rezultati. Tokom terapije nastupile su statistički visokoznačajne promene u obe grupe: oralno naginjanje gornjih i vestibularno naginjanje donjih sekutića. Promene su bile izraženije u grupi bolesnika lečenih Herbst aparatom (p lt 0,001). Nagib gornjih sekutića promenjen je prosečno oko 9°, a donjih oko 7°. Odnos molara i incizalni razmak su u potpunosti korigovani na kraju lečenja u grupi lečenoj Herbst aparatom, dok su isti parametri u grupi sa aktivatorom bili nepotpuno korigovani. Nijedan od primenjenih aparata, na završetku lečenja, nije izazvao promene u vertikalnom preklopu sekutića. Zaključak. Poređenje terapijskih efekata Herbst aparata i aktivatora kod bolesnika uzrasta 14-21 godinu pokazalo je da je Herbst aparat efikasniji u korekciji dentoalveolarne malokluzije klase II odeljenja 1 nego aktivator

Primena fotogrametrije za prostorne analize u ortodontskoj dijagnostici

Introduction Lundstrom segmental analysis is often used analysis in orthodontic diagnosis. It includes measurements of available and needed space in the arch in order to determine whether there is a lack or excess of space for proper teeth alignment. Measurements are traditionally performed on plaster study models, but with recent developments of computer-based systems, there is an increase in use of digital models in measuring process. The aim of this study was to present a photogrammetry based measurement approach that requires no specialized and expensive hardware and compare results with ones obtained on 3D scanned models. Material and method On 50 plaster study models measurements of 24 teeth, widths of 12 segments and Lundstrom segmental analysis were performed. 3D scanned study models were analyzed in the photogrammetry software OrthoPhoto4D on the set of four photographs of the study model in custom made measurement apparatus. The software corrects for finite distance of the camera and corrects errors due to perspective distortion. Results Statistical analysis performed on obtained measurements provided Bland-Altman plots that strongly suggested high degree of correspondence between the two measurements methods. Discrepancies for maxilla for individual segments were under 0.25 mm with standard deviation of up to 0.16 mm, and less than 1 mm and deviation of up to 0.4 mm for complete arch. For mandible the differences were up to 0.27 mm for segments with 0.15 mm deviation and 0.6 mm for complete arch with up to 0.24 mm deviation. Correlation coefficient was over 0.985 in all cases. Conclusions Both analyzed methods can be equally used in clinical practice.Uvod Najčešća prostorna analiza koja se koristi u ortodontskoj dijagnostici je Lundstromova segmentna analiza. Na osnovu dobijenih rezultata merenja upoređuje se potreban i raspoloživ prostor u zubnom nizu i dobijaju informacije o višku ili manjku prostora za pravilan smeštaj zuba. Merenja se tradicionalno vrše na gipsanim studijskim modelima, ali je usled razvoja računarskih sistema sve prisutnija upotreba digitalnih reprezentacija modela u procesu merenja. Cilj ovog rada je bio da se predstavi fotogrametrijski pristup merenjima koji ne zahteva specijalizovan i skup hardver i dobijeni rezultati uporede sa merenjima na skeniranim 3D modelima. Metod Na 50 studijskih modela su merene meziodistalne širine 24 zuba, te širine 12 segmenata i izvršena je Lundstromova prostorna analiza. Merenja su vršena na 3D skeniranom modelu studijskim modelima i u fotogrametrijskom programu OrthoPhoto4D na osnovu četiri fotografije modela u namenski projektovanom držaču modela. Program uzima u obzir konačnu udaljenost kamere od modela i vrši korekcije grešaka nastalih usled perspektivne distorzije. Rezultati Provedena statistička analiza na prikupljenim merenjima i priloženi Bland-Altman grafici snažno sugerišu da postoji visok stepen saglasnosti između dva metoda merenja. Odstupanja za maksilu za pojedinačne segmente su iznosila do 0,25 mm sa standardnom devijacijom od 0,16 mm, za celu vilicu manje od 1 mm uz devijaciju od 0,4 mm, za mandibulu odstupanja za segmente iznose ispod 0,27 mm uz devijaciju od 0,15 mm, te za celu vilicu do 0,6 mm uz devijaciju od 0,24 mm. Koeficijenti korelacije su preko 0,985 u svim slučajevima. Zaključak Fotogrametrijski metod se može opravdano koristiti u kliničkoj praksi za dijagnostiku ortodontskih nepravilnosti

Novi metod fotogrametrijskih merenja studijskih modela u ortodonciji

Introduction/Objective Rapid developments in information technologies lead to the wider use of digital representations of dental study models in orthodontics. Most popular way of digitizing the models is to use a 3D scanner and then perform measurements on 3D models, which requires additional and expensive hardware and software resources. In this paper we present an alternative approach based on the use of photogrammetry in the newly developed OrthoPhoto4D software that calculates and corrects perspective distortion errors. Methods We measured individual tooth width for 24 teeth, 12 two-teeth segments as well as inter-molar and inter-canine distances on 50 models. Measurements are performed in OrthoPhoto4D software that uses four photographs of each model for measurements, uses QR codes for automation, calculates the camera position and corrects perspective distortion-caused errors in measurements. Obtained measurements are compared to ones obtained from models generated by structured light 3D scanner. Results Statistical analysis strongly indicates that there is no significant difference between the two methods. The recorded differences also have no clinical impact as they have mean values of 0.2 mm for individual tooth widths, approximately 0.2 mm for two teeth segments, and under 0.3 mm for both inter-canine and inter-molar distances. All recorded differences fall within the expected measurement error. Conclusion We concluded that the described photogrammetry measurements performed in OrthoPhoto4D can be used in diagnosis and therapy planning.Uvod/Cilj Brzi razvoj informacionih tehnologija doveo je do široke upotrebe digitalnih studijskih modela u ortodonciji. Najpopularniji način digitalizacije modela je korišćenje 3D skenera, a zatim i merenja na 3D modelima, što zahteva dodatne i skupe hardverske i softverske resurse. U ovom radu predstavljamo alternativni pristup zasnovan na korišćenju fotogrametrije u novorazvijenom softveru OrthoPhoto4D, koji izračunava i ispravlja greške nastale kao posledica perspektivne distorzije. Metod Na 50 studijskih modela merena je meziodistalna širina za 24 zuba, širina 12 segmenata dvostrukih zuba, kao i interkanina i intermolarna širina. Merenja su vršena u programu OrthoPhoto4D, koji koristi četiri fotografije svakog merenog modela, QR kodove za automatizaciju, računa udaljenost kamere i koriguje greške merenja izazvane perspektivom. Merenja su poređena sa rezultatima dobijenim na modelima generisanim 3D skenerom. Rezultati Analiza rezultata snažno ukazuje na to da ne postoji statistički značajna razlika između dva metoda. Zabeležene razlike takođe nemaju klinički značaj, jer su srednje vrednosti do 0,2 mm za pojedinačne širine zuba, do približno 0,2 mm za segmente od dva zuba i ispod 0,3 mm za interkaninu i intermolarnu širinu. Sve zabeležene razlike su unutar očekivane greške merenja. Zaključak Opisani metod fotogrametrijskih merenja u programu OrthoPhoto4D se može koristiti u dijagnozi i planiranju ortodontske terapije

Zavisnost između percepcije bola kod pacijenata sa šest različitih ortodontskih žica i teskobe zubnih nizova

Introduction Forces generated in orthodontic treatment with fixed appliances create tension and compression zones in the periodontal ligament resulting in a painful experience for patients. In the first phase of orthodontic treatment, when leveling of teeth is needed, nickel-titanium (NiTi) archwires can be completely engaged in brackets, even in the cases of extreme crowding, exerting small forces. There is a great individual variation in the pain perception related to the application of orthodontic forces. Objective The aim of this study was to investigate the pain perception among patients with dental crowding after insertion of six different NiTi orthodontic archwires as a part of fixed appliances in the first stage of orthodontic treatment. Methods The study was conducted on a sample of 189 orthodontic patients receiving one of six different either superelastic or heat activated NiTi archwires, in the first phase of orthodontic treatment. Pain perception was evaluated in groups of patients with different degree of crowding. The modified McGill Pain Questionnaire with Visual Analogue Scale was used to evaluate the quality and intensity of pain. Statistical analysis was performed using simple descriptive statistics, and Pearson's chi-square test with statistical significance of p lt 0.05. Results Majority of patients reported pain as discomfort or pressure of moderate intensity caused by chewing or biting, started within 12 hours, carried on for 3-4 days, and decreased over time without self-medication. Conclusion No correlation was found between pain perception among patients with different types of NiTi archwires and the degree of crowding.Uvod Ortodontske sile kojima se tokom terapije fiksnim aparatima pomeraju zubi dovode do istezanja i kompresije parodontalnih vlakana, te pojave bola kod pacijenata. U prvoj fazi ortodontskog lečenja, kada se zubi nivelišu, žice od legure nikl-titanijuma proizvode relativno malu silu i mogu se potpuno ligirati u slotove bravica, čak i u slučajevima velike teskobe. Postoje veoma velike individualne varijacije u percepciji bola prilikom primene ortodontskih sila. Cilj rada Cilj istraživanja je bio da se ispita percepcija bola kod osoba s teskobom u zubnim nizovima nakon ligiranja šest različitih ortodontskih žica u sklopu prve faze terapije fiksnim aparatima. Metode rada Studija je urađena na uzorku od 189 pacijenata kojima je u okviru ortodontskog lečenja fiksnim aparatima bila ligirana jedna od šest različitih superelastičnih ili termo žica od legure nikl-titanijuma. Percepcija bola je procenjivana kod osoba s različitom izraženošću teskobe. Korišćen je modifikovani Makgilov (McGill) upitnik za bol s Vizuelnom analognom skalom radi opisivanja kvaliteta i intenziteta bola. Statistička obrada podataka je obuhvatila deskriptivnu statističku analizu i primenu h2-testa sa statističkom značajnošću od p lt 0,05. Rezultati Najveći broj ispitanika je opisao bol kao neprijatnost ili pritisak srednjeg intenziteta izazvan žvakanjem ili dodirom, koji je počinjao do 12 sati od ligiranja žice, trajao je tri-četiri dana i smanjivao se bez primene lekova. Zaključak Nije utvrđena statistički značajna razlika u percepciji bola kod osoba s različitom izraženošću teskobe zubnih nizova kojima su bile ligirane superelastične i termo žice od legure nikl-titanijuma