Efikasnost alternativnog programa nastave fizičkog vaspitanja u mlađim razredima osnovne škole

Istraživanje je sprovedeno sa ciljem da se utvrdi da li alternativni program nastave fizičkog vaspitanja u trajanju od 6 meseci može u potpunosti da zameni postojeći nastavni program i doprinese ostvarivanju potrebnog cilja i zadataka nastave fizičkog vaspitanja u mlađim razredima osnovne škole. Za potrebe istraživanja primenjeno je 11 varijabli za procenu parametara rasta i razvoja, motoričkih sposobnosti i sportsko–tehničkog obrazovanja, kao i procena stavova učenika. Populacija iz koje je izveden uzorak definisana je kao populacija učenika trećeg razreda osnovne škole oba pola, koja živi u gradskoj sredini, koji su zdravi i koji su obuhvaćeni redovnom nastavom fizičkog vaspitanja i alternativnim programom. Uzorak ispitanika činilo je 209 učenika, u eksperimentalnoj grupi 105 ispitanika, dok je uzorak kontrolne grupe činilo 109 ispitanika. Na osnovu dobijenih rezultata istraživanja, zaključeno je da alternativni program ima pozitivne efekte u ostvarivanju cilja i zadataka nastave fizičkog vaspitanja, i da ne postoji statistički značajna razlika u rezultatima merenja u odnosu na redovan program. Takođe, zaključeno je da alternativni program ima isti uticaj na razvoj segmentarne brzine, eksplozivne snage, statičke sile, repetitivne snage i sprinterske brzine, kao i redovan progam nastave fizičkog vaspitanja. Nisu utvrđene razlike u napretku dece u odnosu na pol kod sportsko-tehničkog obrazovanja, kao ni kod stavova učenika kod alternativnog programa u odnosu na redovni program nastave fizičkog vaspitanja.The study has been taken aiming to determine whether an alternative teaching program of physical education classes in the duration of 6 months can completely replace the existing curriculum and to contribute in achieving the required objectives and tasks of physical education classes in younger grades of elementary schools. For the purposes of this research, 11 variables have been applied for assessing the parameters of children’s physical growth and development, their motor skills and sport–technical education, as well as an assessment of evaluation the physical education teaching. The population from which the sample is performed is defined as a population of the third grade elementary schoolchildren of both gender, living in an urban environment, healthy and that are included in both regular physical education classes and an alternative program. The examinee sample is consisted of 209 schoolchildren, 105 examinees in the experimental group, while the sample control group is consisted of 109 examinees. Based on the obtained research results, it was concluded that an alternative program has positive effects on reaching the objectives and goals of physical education teaching classes, and that there is no statistical significant difference in the results of measurement from the regular program. It was also concluded that an alternative program has the same impact on the development of segmentary speed, explosive power, static force, repetitive strength and sprint speed as the regular program of the physical education teaching classes. The differences were not determined in the progress of schoolchildren in relation to gender at sport–technical education as well as in the evaluation of physical education teaching classes at the alternative comparing to the regular teaching program of physical education classes

Re-entrant spin glass transition in LiCr0.175mn1.825O4 spinel

Magnetic properties of Cr3+ substituted LiMn2O4 spinel have been investigated by measuring both temperature and field dependence of DC magnetization, as well as temperature dependence of AC susceptibility. Obtained results point to the reentrant spin glass behavior in the low temperature region where system undergoes long range antiferromagnetic transition at TN=42 K followed by the spin glass transition at Tf=22 K. High temperature behavior is of the Curie-Weiss type with effective magnetic moment corresponding to the sample's chemical composition.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

VIRTUAL SPACE OF THE BASIC MOTORIC STRUCTURES

Abstract. A battery composed of 18 composite motor tests, which were assumed to be proper indicators of 9 hypothetical motor dimensions, was analyzed based on the hypothetical model of motor dimensions. The tests were applied on a sample of 220 girls aged ten. By using the factor analysis, the previous predictions of the existence of 9 factors which can generally be used for explaining motor space on the applied sample have not been confirmed because a certain number of variables do not saturate those basic vectors which were thought to determine the assumed motor structures. The results of this paper disaffirm the present validation of structural theories of motor skills and confirm the opinion that at this level of physical education research it is not possible to define the unique model of basic structures which could be used to explain the motor space of the entire human population. Considering the specificities of the sample (maturation, gender, the achieved level of motor skills, cognitive, conative and other characteristics of the sample), there is a great number of hypothetical models which can be used to explain the structure of motor space.Key words: measuring instruments battery, basic vectors, motor skills

CONTRIBUTION TO THE KNOWLEDGE OF PHYLLONORYCTER ISSIKII (KUMATA, 1963) (LEPIDOPTERA, GRACILLARIIDAE) IN SERBIA

Phyllonorycter issikii (Kumata, 1963) is an invasive leaf-mining moth originating from Asia. It develops on plants from the genus Tilia. The first finding of this species in Serbia was in 2013, and since then, the range of the species has spread, and we have found it at five more localities on T. cordata and T. tomentosa. Ph. issikii was studied at two of these localities. The existence of two overlapping generations was determined. No significant differences in the intensity of the attack between them were noticed. Differences existed only between the localities where the research was conducted and between the Tilia species on which Ph. issikii was found. As regards the lime species, the moth preferred T. cordata to T. tomentosa at both localities. Two species of parasitoids were reared from the collected material: Pediobius saulius (Walker, 1839) and Minotetrastichus frontalis (Nees, 1834)

Valorization of non-balanced coal reserves in Serbia for underground coal gasification

In the name of a better and safer energy future, it is our responsibility to focus our knowledge and activities to save on imported liquid and gas fossil fuels, as well as coal on which energy security of Serbia is based. The rationalization in the use of available energy resources certainly positively affects economy and the environment of a country. This paper indicates motivations for the application of the underground coal gasification process, as well as surface gasification for Serbia. The goal is to burn less coal, while simultaneously utilizing more gas from the onsite underground coal gasification, or by gasification in various types of gas generators mounted on the surface. In both cases, from the obtained gas, CO2, NOx, and other harmful gases are extracted in scrubbers. This means that further gas combustion byproducts do not pollute the atmosphere in comparison with traditional coal combustion. In addition, complete underground coal gasification power requirements could be offset by the onsite solar photovoltaic power plant, which furthermore enhances environmental concerns of the overall coal utilization

Utilization of sweet and whey in the production of fermented beverages

Na osnovu pokusa autori predlažu tehnologiju napitaka od slatke i kisele surutke sa dvostrukom pasterizacijom i homogenizacijom te cijepljenjem, sa 2 % kulture L. heleveticus.On the basis of the experimental results the authors suggest a technology of beverages from sweet and acid whey with double pasterization and homogenization followed by the inoculation with 2 % of the culture of L. helveticus

Suzbijanje korova u usevu angelike (Angelica archangelica L.)

Plantažno gajenje lekovitog bilja je u ekspanziji, a s obzirom na to da suzbijanje korova predstavlja najveći izazov u ovoj proizvodnji, cilj rada je bio ispitivanje mogućnosti njihovog suzbijanja malčiranjem. Osim toga, u istraživanje je bio uključen i herbicid metamitron čija je primena u ovakvim usevima prihvatljiva u nekim zemljama. Kao eksperimentalni usev izabran je usev angelike (A. archangelica L.) čije etarsko ulje iz korena je jedno od najcenjenijih na tržištu, pa se može očekivati povećanje proizvodnih površina. Ogled je postavljen kao potpuno slučajan blok sistem u četiri ponavljanja i to u pet tretmana: agrotekstilna vodopropusna folija, piljevina, herbicid metamitron, kontrola bez korova (pozitivna) i kontrola sa korovima (negativna). Najveća zakorovljenost zabeležena je u negativnoj kontroli i u tretmanu sa primenom herbicida metamitron. Malč od piljevine rezultirao je smanjenjem zakorovljenosti u odnosu na prethodna dva tretmana. Agrotekstilna folija i redovno plevljena kontrola su bile bez prisustva korova. Dakle, najbolja efikasnost u suzbijanju korova postignuta je primenom agrotekstilne malč folije, koja je u potpunosti sprečila nicanje korova (efikasnost 100%). Znatno slabiji efekat je ostvaren primenom piljevine (efikasnost 51,28%), dok je metamitron svežu biomasu korova redukovao za samo 26,71%. Dobijeni rezultati pokazuju da je malčiranje kao fizička metoda suzbijanja korova u usevu angelike podesnije u poređenju sa primenom herbicida metamitron ukoliko u usevu dominiraju travne vrste, koje nisu u spektru delovanja ovog herbicida. Značaj ovih rezultata je utoliko veći što u našoj zemlji metamitron, kao ni drugi herbicidi, nije registrovan za primenu u lekovitom bilju

Spojna sredstva sistema 'Huck BobTail' - novo rešenje za visokovredne zavrtnjeve sa zaključavanjem

Alcoa Fastening Systems, introduces the Huck BobTail, representing the most advanced fastening technology to date. Recognized as the next-generation lockbolt, the Huck BobTail delivers 5 times the fatigue strength of conventional nuts and bolts, and is engineered to provide the highest level of strength, reliability, and vibration-resistant performance. Engineered to meet the challenges of a wide range of assembly applications, BobTail offers high performance and easy, quick installation.Firma 'Alcoa Fastening Systems' konstruisala je 'Huck BobTail' sistem mehaničkih spojnih sredstava i predstavila ga kao jednu od najnaprednijih tehnologija spajanja do danas. Prepoznat kao zaključavajući zavrtanj (antivandal) naredne generacije, 'Huck BobTail' donosi pet puta veću čvrstoću na zamor od standardnih zavrtnjeva sa navrtkom, a konstruisan je tako da pruži visoku čvrstoću, pouzdanost i otpornost na vibracije i u najekstremnijim uslovima. Konstruisan da zadovolji širok spektar sistema za spajanje, 'BobTail' odlikuju visoke performance kao i jednostavna i brza ugradnja