Background. Handball is a team sport that demands quick reflexes and precise motor skills, particularly in shooting. Players' ability to shoot accurately and swiftly while stationary makes upper limb reaction time crucial for success. Objectives. The research objective is to study the relationship between the motor time of the muscles of the arms and the index of accuracy of shooting from constancy in fourth-stage students in handball. Methods. The researchers used the descriptive method because it is one of the methods used in the research on a sample of students of the fourth stage of the college of Physical Education and Sports Sciences, where the sample consisted of 29 male students from the community of origin, 43 students. Results. The results showed that the variables under study have significant direct correlations with the accuracy variable of shooting from stability, where the correlation of the motor response time was r=0.73 (p=0.047), the speed of movement of the arm r=0.87 (p=0.380), the maximum decrease in the knee angle variable r=0.77 (p=0.360) and the maximum decrease in the center of mass of the body was r=0.79 (p=0.380). In contrast, the degree of elbow angle during the ball's exit was variable, r=0.62 (p=0.560), and the degree of wrist angle during the ball's exit was variable, r=0.79 (p=0.380). Conclusion. The study found that motor response speed, knee angle, and body center of mass significantly impact skill accuracy. These factors balance the player and maintain the movement path, resulting in an integrated skill. The accuracy of shooting from consistency in handball is primarily determined by the angle taken at each stage, particularly during the exit phase of the ball. This study stands out with novelty for its focus on university handball players, providing an accurate biomechanical analysis of this category of students, which has not been studied. The analyzed variables included elbow angle, wrist angle, knee flexion, and center of body mass during different shooting phases. In addition, using a non-random sample is a limitation that may affect the generalizability of the results.
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Five new lanthanide complexes based on azomethine (Schiff bases) ligands have been synthesized, including La, Nd, Er, Gd, and Dy. Complexes were synthesized using the azomethine Schiff bases resulting from condensation reactions between 4-aminoantipyrine and acetonylacetone. The structural characteristics of azomethine obtained are characterized quantitatively and qualitatively through various techniques, including elemental analyses, magnetic susceptibility measurement, molar conductivity, infrared, ultraviolet absorption, GC-mass, and 1H- and 13C-NMR spectroscopy studies. The structural characteristics of Ln+3 complexes indicate that the complexes possess a composition of a specific type. Based on the elemental analyses, magnetic
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Abstract:
The models of time series often suffer from the problem of the existence of outliers that accompany the data collection process for many reasons, their existence may have a significant impact on the estimation of the parameters of the studied model. Access to highly efficient estimators is one of the most important stages of statistical analysis, And it is therefore important to choose the appropriate methods to obtain good estimators. The aim of this research is to compare the ordinary estimators and the robust estimators of the estimation of the parameters of
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The Ilkhanid Mongols (651-756 AH / 1253-1355 AD) were interested in urbanization and construction in keeping with civilized countries and to have an architectural imprint that competed with the neighboring nations. The Ilkhan Öljeitü Muḥammad Khudābandeh (703-716 AH / 1303-1316 AD), known for his love of building and construction, wanted to have a capital that would immortalize his name and history, so he ordered its construction to compete with contemporary cities, and he summoned workers and engineers from all over the world to contribute to its construction. The city has several educational and service institutions such as schools, ribats, khanqas, mosques, hospitals, markets, and baths, as well as a mausoleum for him, which
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Background: Polymethylmethacrylate (PMMA) is the most ‎commonly used mâ€aterial in denture construction. This material is ‎far from ideal in fulfilling the‎ mechanical requirements, like low impact and transverse strength and poor thermal conductivity are present in this material. The purpose of this study was to study the effect of addition a composite which include 1%wt silanized silicone dioxide nano fillers (SiO2) and 1wt% oxygen plasma treated polypropylene fiber (PP) on some properties of heat cured acrylic resin denture base material (PMMA). Materials and methods: One hundâ€red (100) prepared specimens were divided into five groups according to the tests, each group consisted of 20 specimens and t
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A new ligand complexes have been synthesis from reaction of metal ions of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) with schiff base LH. 5-[(2-Hydroxy-naphthalen-1-ylmethylene)-amino]-2-phenyl-2,4-dihydro-pyrazol-3-one, this ligand was characterized by Fourier transform infrared (FTIR), UV-vis, 1H, 13CNMR, and mass spectra. All complexes were characterized by techniques micro analysis C.H.N, UV-vis and FTIR spectral studies, atomic absorption, chloride content, molar conductivity measurements and magnetic susceptibility. The ligand acts as bidentate, coordination through nitrogen atom from azomethin group and deprotonated phenolic oxygen atom. The spectroscopic and analytical measurements showed that
... Show MoreNew series of 4, 4'-((2-(Aryl)-1H-benzo [d] imidazole-1, 3 (2H)-diyl) bis (methylene)) Diphenol (3a-g) was successfully synthesized from cyclization of the reduction product of bis Schiff bases (2) with aryl aldehydes bearing phenolic hydroxyl in the presence of acetic acid. The structure of these compounds was identified from FT-IR, 1H NMR, 13C NMR and EIMs. The Antioxidant capability was screened by DPPH and FRAP assays. Both assays showed antioxidant capability more than BHT as well. Compounds 3b and 3c showed antioxidant capacity slightly less than ascorbic acid. The docking study for theses compound was carried out as III DNA polymerase inhibitor. The results of docking demonstrated that the increase in hinderances around phenolic hydr
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Background: Polymethyl methacrylate (PMMA) is the most commonly used material in denture fabrication. The material is far from ideal in fulfilling the mechanical requirement. The purpose of this study was to evaluate the effect of addition of 3% wt of treated (silanized) Titanium oxide Nano filler on some physical and mechanical properties of heat cured acrylic denture base material. Materials and methods: 100 specimens were constructed, 50 specimens were prepared from heat cure PMMA without additives (control) and 50 specimens were prepared from heat cure PMMA with the addition of TiO2 Nano fillers. Each group was divided into 5 sub groups according to the test performed which was mixed by probe ultra-sonication machine. Results: A highly
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