57 research outputs found
Efekti programiranog treninga na promene eksplozivne snage i agilnosti mladih odbojkašica
The doctoral dissertation was done with the aim of determining the effects a programmed training would have on the changes in the explosive strength and agility of young female volleyball players. The sample was constituted of 30 female volleyball players, aged 14 to 16, who, at the time of the testing process, were active players of two volleyball clubs from Nis, OK ‘Desetka’ and OK ‘Millennium’. The examinees were divided into two groups – the experimental one (n=15) and the control group (n=15). The experimental group was comprised of the players from the club OK ‘Desetka’, who, apart from the basic technical and tactical training process, underwent a specially designed programme for developing explosive power and agility two times a week (on Tuesdays and Thursdays). The experimental programme was applied during the period pf preparations before the official beginning of the regional competitions for cadets. The control group was comprised of the players from the club OK ‘Millennium’, who, during the same period of time, underwent only those training sessions which had previously been planned within the annual plan and programme of the club. The sample of the measuring instruments for evaluating the explosive strength included four sets of tests: squat jump (SJ), countermowement jump (CMJ), drop jump (DJ),one-legged countermovement jump (OLCMJ). The agility of the examinees was evaluated through seven tests: T-test, Hexagon Agility Test, Illinois Agility Test, 9-6-3-6-9 Agility Test, Japan Agility Test, 505 Agility Test, Step-Hop Agility Test. Data analysis was done by the Kolmogorov-Smirnov Test. The effects of the progremmed training on the development of the explosive strength and agility of the young female volleyball players was determined by the Covariance Analysis, AKNOVA. The results obtained in such a way showed the statistically significant improvement in the parameters tested within the experimental group. The difference was insignificant in the OLCMJ test only. The results point to the conclusion that the experimental training programme had positive effects on the changes of explosive strength and agility of young female volleyball players
ECO-FRIENDLY ELDERBERRY BASED SORBENT FOR REMOVING Pb2+IONS FROM AQUEOUS SOLUTIONS
Abstract
Elderberry (Sambucus nigra) pith was modified with polyethyleneimine (PEI) in order to improve the adsorption properties. Characterization of both dried Sambucus nigra pith (DSNP) and amino modification of elderberry pith with branched PEI (PEI/DSNP) was performed by: Fourier-transform infrared spectroscopy (FTIR), optical microscopy, and porosity determination. The amine and ester number, as well as acid value, were determined on DSNP and PEI/DSNP samples using standard volumetric methods. The samples were used as adsorbents for Pb2+ions from an aqueous solution in a batch system. The obtained results were fitted using suitable equilibrium isotherm and kinetic models. The maximum adsorption capacity for Pb2+ions on DSNP andaminаted sample, obtained using Langmuir adsorption isotherm at 298 K, are 18.9 and 47.8 mg g-1, respectively. Based on the kinetic studies, the adsorption process follows the pseudo second-order model. Thermodynamic parameters showed that the adsorption process is endothermic and spontaneous. In general, the overall adsorption process was improved by modifying starting material withbranched PEI modifier by introducing large numbers of amino functionalities having high affinity to cations
Determination of toxic elements (mercury, cadmium, lead and arsenic) in shellfish samples
Morski plodovi imaju visoku nutritivnu vrednost, ali sa druge strane postoji rizik od kontaminacije toksičnim elementima. Sadržaj As, Cd, Hg i Pb je određen u četiri vrste školjki Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) i Anadara broughtonii (AB) kupljene u Incheonu, Koreja. Uzorci su analizirani induktivno spregnutom plazmom - masenom spektrometrijom (ICP-MS) nakon mikrotalasne digestije. Izračunati su dnevni/nedeljni unosi za ove elemente u mg/300 g uzorka. Ukupan sadržaj As (neoganski i organski) u svim vrstama je bio veći od dozvoljenog limita preporučenog od Svetske zdravstvene organizacije (WHO). Procenjeni dnevni unosi ostalih elemenata (Hg, Cd i Pb) su niži od maksimalnih podnošljivih granica (MDI) koje je odredila Evropska agencija za bezbednost hrane (EFSA) što ukazuje da nema rizika za konzumente.Bivalve molluscs, which include mussels, oysters and clams, have high nutritional value. On the other hand, seafood may also contain harmful contaminants and other undesirable substances such as mercury and persistent halogenated compounds. Four species of bivalve molluscs Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) and Anadara broughtonii (AB) were bought in Incheon, Korea, in order to determine content of As, Cd, Hg, and Pb and consequently, to estimate the health hazards associated to dietary intake. The samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after microwave digestion. All species showed As content higher than the maximum tolerable limit specified by EFSA. Estimated daily intake of Hg, Cd and Pb from consumption of 300 g was very low and hence poses no toxicological risk
Synchronizing inventory and transport within supply chain management
The problem considers synchronized optimization of inventory and transport, and focuses on producer-distributor relations. Particular attention is paid to developing a mathematical model and an optimization problem that can be used to minimize the overall distribution cost by an appropriate placement of warehouses and cross-docking points. Solutions to this problem are explored using genetic algorithms and ideas from graph/network theory.
Note: there are three separate reports contained within the uploaded .pdf file
Chemometric characterization of sellfish according to their element composition
Cilj ove studije je klasifikacija biološki različitih vrsta školjki na osnovu sadržaja esencijalnih elemenata primenom hemometrije. Sadržaj esencijalnih elemenata kao što su Co, Cr, Cu, Mn, Ni, Se, Zn, i Fe je određen u četiri biološki različite vrste školjki Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) i Anadara brоughtonii (AB). Analizitani uzorci su kupljeni u Incheonu, Koreja. Sadržaj esenicjalnih elemenata je određen primenom induktivno spregnute plazme kuplovane sa masenom spektrometrijom (ICP-MS) nakon mikrotalasne digestije. Hemometrijske tehnike pokazuju grupisanje ispitivanih uzoraka školjki prema sadržaju esencijalnih elemenata i identifikuju elemente najvažnije za klasifikaciju.The main aim of current study was classification of four biologically different sellfish species such as bivalve molluscs Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) and Anadara broughtonii (AB) bought in the Incheon, South Korea. Content of essencial ellements such as Co, Cr, Cu, Mn, Ni, Se, Zn, and Fe were determined by using inductively coupled plasma mass spectrometry (ICP-MS) after closed-vessel microwave digestion. Chemometrics techniques showed classification of sellfish smaples based on biological species and identified elements most important for classification
Chemometric characterization of sellfish according to their element composition
Cilj ove studije je klasifikacija biološki različitih vrsta školjki na osnovu sadržaja esencijalnih elemenata primenom hemometrije. Sadržaj esencijalnih elemenata kao što su Co, Cr, Cu, Mn, Ni, Se, Zn, i Fe je određen u četiri biološki različite vrste školjki Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) i Anadara brоughtonii (AB). Analizitani uzorci su kupljeni u Incheonu, Koreja. Sadržaj esenicjalnih elemenata je određen primenom induktivno spregnute plazme kuplovane sa masenom spektrometrijom (ICP-MS) nakon mikrotalasne digestije. Hemometrijske tehnike pokazuju grupisanje ispitivanih uzoraka školjki prema sadržaju esencijalnih elemenata i identifikuju elemente najvažnije za klasifikaciju.The main aim of current study was classification of four biologically different sellfish species such as bivalve molluscs Ruditapes philippinarum (Manila clam, MC), Yesso scallop (YS), Tegillarca granosa (TG) and Anadara broughtonii (AB) bought in the Incheon, South Korea. Content of essencial ellements such as Co, Cr, Cu, Mn, Ni, Se, Zn, and Fe were determined by using inductively coupled plasma mass spectrometry (ICP-MS) after closed-vessel microwave digestion. Chemometrics techniques showed classification of sellfish smaples based on biological species and identified elements most important for classification
Prospective of the LDI MS to characterization the corrosion products of silver-copper alloys on an example of the Ag-Cu-X (X- Zn, Pd, In) system
This work presents the perspective of applying the laser desorption/ionization mass spectrometry (LDI MS) for characterization the anode film of the Ag60Cu26Zn14, Ag58.5Cu31.5Pd10, and Ag63Cu27In10 alloys (at high concentrations of chloride ions in solutions). The reference LDI mass spectra of anode films of pure Ag and Cu have been used for the identification of product corrosion. Knowing the clusters detected in the reference spectra lead to the facilitating identification of the LDI mass spectrum of the sample and reduces the analysis time. The LDI MS analysis of these alloys revealed that the predominant corrosion product are AgCl (from AgnCln+1−/+, n = 1–3), and CuCl (from “superhalogen” CumCln− clusters, m = 1–2, n = 2–6); it also revealed Cu2(OH)3Cl (from Cu2(OH)(H2O)2+) and Cu2O (from Cu(H2O)+, Cu2O doped with chlorine). These results are in accordance with the X-ray diffraction and Raman analysis. The LDI MS spectra of alloys contain the additional peaks formed due to the mutual influences of different metals in the alloys (AgCuCl3− (AgCl-CuCl2−), AgCu2Cl4− (AgCl-CuCl-CuCl2−), and Ag2CuCl4− (AgCl-AgCl-CuCl−), which is consistent with the identified corrosion products. It should be noted that the LDI MS suggest the presence of CuCl2, which can be interpreted as the corrosion products retained in the porous films of alloys, and not detected by the other methods due to a small amount. The future theoretical and experimental studies of metal clusters, significant for metallurgy, can contribute that the LDI MS is becoming a powerful analytical tool for characterization the metal surfaces
Development of SARS-CoV-2 N-protein specific capture ELISA
Ta na dijagnoza ljudi sa sumnjom na infekciju SARS-CoV-2 je od suštinskog zna aja za
suzbijanje globalnog širenja COVID-19. Prisustvo SARS-CoV-2 može se otkriti RT-PCRom (otkriva RNK virusa) ili detekcijom prisustva virusnih antigena u biološkim te nostima
ELISA-om ili sli nom tehnikom koje koriste antitela razvijena u životinjama. Cilj studije
je bio uspostavljanje kvantitativnog testa koji se zasniva na koriš enju poliklonskih seruma
za rutinsko odre ivanje koncentracije SARS-CoV-2 nukleokapsidnog proteina merenjam
apsorbancije u standardnoj mikrotitarskoj plo ici sa 96 bunara. Za potrebe razvoja testa
proizveden je rekombinantni N-protein i koriš en za proizvodnju antiseruma u miševima i
ze evima. Proizvedeni antiserumi su pre iš eni i odre en im je titar. Poliklonskiantiserumi
visokog afiniteta specifi ni za N-protein koriš eni su za razvoj ELISA testa specifi nog za
ovaj protein. Test se zasniva na koriš enju poliklonskih seruma miševa koji su adherirani
na dno bunara mikrotitarske plo ice za hvatanje N-proteina iz uzorka. Razli ite
koncentracije rekombinantnog N-proteina su koriš ene za standardnu krivu za
kvantifikaciju proteina. N-protein vezan za antitela miševa je detektovan ze jim
poliklonskim serumom i anti-ze jim antitelom povezanim sa enzimom koji obezbe uje
spektrofotometrijsko merenje. Uspešno smo razvili prototip ELISA testa za kvantifikaciju
N-proteina sa granicom detekcije u opsegu od ng/mL. Prose na vrednost LOD za prototip
ELISA testa za detekciju N-proteina je 9,2 ng/mL, dok je prose na vrednost LOQ
10,2 ng/mL. Pokazali smo da su proizvedeni poliklonski antiserumi pogodni za detekciju
N-proteina sa sli nim ili boljim afinitetom i specifi noš u od komercijalnih antitela.
Štaviše, prototip ELISA testa se može koristiti sa zadovoljavaju om pouzdanoš u za
kvantifikaciju N-proteina u uzorcima bogatim proteinima, poput ljudskih seruma.The accurate diagnosis of people with suspected infection with the SARS-CoV-2 is
essential to curb the global spread of COVID-19. The presence of SARS-CoV-2 can be
detected by RT-PCR (it detects RNA of the virus) or by the presence of viral antigens in
biological fluids in ELISA or similar techniques using antibodies developed in animals.
The aim of the study was the establishment of a quantitative polyclonal sera-based test for
routine measurement of the concentration of SARS CoV-2 nucleocapsid protein using
absorbance measurement in a standard 96-well microtiter plate. For the purposes of the test
development, recombinant N protein was produced and used for the production of mice
and rabbit antisera. Produced antisera were purified and titer was determined. High-affinity
polyclonal N-protein specific antisera were used for N-protein specific ELISA test
development. The test is based on mice polyclonal sera adhered to microtiter plate bottom
for the capture of the N protein from the specimen. Various concentrations of the
recombinant N-protein were used to generate a standard curve for protein quantification.
The N-protein bound to the mice antibodies was detected with rabbit polyclonal sera and
anti-rabbit antibody coupled to an enzyme that provides spectrophotometric measurement.
We have successfully developed the prototype ELISA for the quantification of N-protein
with the detection limit being in the range of ng/mL. The average LOD value for the
prototype ELISA was determined to be 9.2 ng/mL, while the average LOQ value was
10.2 ng/mL. We have demonstrated that produced polyclonal antisera are suitable for the
detection of N-protein with affinity and specificity similar to, or better than commercial
antibodies. Furthermore, the prototype ELISA can be used with satisfactory confidence for
quantification of the N-protein in protein-rich samples, similar to human sera.Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5362
Development of SARS-CoV-2 N-protein specific capture ELISA
Ta na dijagnoza ljudi sa sumnjom na infekciju SARS-CoV-2 je od suštinskog zna aja zasuzbijanje globalnog širenja COVID-19. Prisustvo SARS-CoV-2 može se otkriti RT-PCRom (otkriva RNK virusa) ili detekcijom prisustva virusnih antigena u biološkim te nostimaELISA-om ili sli nom tehnikom koje koriste antitela razvijena u životinjama. Cilj studijeje bio uspostavljanje kvantitativnog testa koji se zasniva na koriš enju poliklonskih serumaza rutinsko odre ivanje koncentracije SARS-CoV-2 nukleokapsidnog proteina merenjamapsorbancije u standardnoj mikrotitarskoj plo ici sa 96 bunara. Za potrebe razvoja testaproizveden je rekombinantni N-protein i koriš en za proizvodnju antiseruma u miševima ize evima. Proizvedeni antiserumi su pre iš eni i odre en im je titar. Poliklonskiantiserumivisokog afiniteta specifi ni za N-protein koriš eni su za razvoj ELISA testa specifi nog zaovaj protein. Test se zasniva na koriš enju poliklonskih seruma miševa koji su adheriranina dno bunara mikrotitarske plo ice za hvatanje N-proteina iz uzorka. Razli itekoncentracije rekombinantnog N-proteina su koriš ene za standardnu krivu zakvantifikaciju proteina. N-protein vezan za antitela miševa je detektovan ze jimpoliklonskim serumom i anti-ze jim antitelom povezanim sa enzimom koji obezbe ujespektrofotometrijsko merenje. Uspešno smo razvili prototip ELISA testa za kvantifikacijuN-proteina sa granicom detekcije u opsegu od ng/mL. Prose na vrednost LOD za prototipELISA testa za detekciju N-proteina je 9,2 ng/mL, dok je prose na vrednost LOQ10,2 ng/mL. Pokazali smo da su proizvedeni poliklonski antiserumi pogodni za detekcijuN-proteina sa sli nim ili boljim afinitetom i specifi noš u od komercijalnih antitela.Štaviše, prototip ELISA testa se može koristiti sa zadovoljavaju om pouzdanoš u zakvantifikaciju N-proteina u uzorcima bogatim proteinima, poput ljudskih seruma.The accurate diagnosis of people with suspected infection with the SARS-CoV-2 isessential to curb the global spread of COVID-19. The presence of SARS-CoV-2 can bedetected by RT-PCR (it detects RNA of the virus) or by the presence of viral antigens inbiological fluids in ELISA or similar techniques using antibodies developed in animals.The aim of the study was the establishment of a quantitative polyclonal sera-based test forroutine measurement of the concentration of SARS CoV-2 nucleocapsid protein usingabsorbance measurement in a standard 96-well microtiter plate. For the purposes of the testdevelopment, recombinant N protein was produced and used for the production of miceand rabbit antisera. Produced antisera were purified and titer was determined. High-affinitypolyclonal N-protein specific antisera were used for N-protein specific ELISA testdevelopment. The test is based on mice polyclonal sera adhered to microtiter plate bottomfor the capture of the N protein from the specimen. Various concentrations of therecombinant N-protein were used to generate a standard curve for protein quantification.The N-protein bound to the mice antibodies was detected with rabbit polyclonal sera andanti-rabbit antibody coupled to an enzyme that provides spectrophotometric measurement.We have successfully developed the prototype ELISA for the quantification of N-proteinwith the detection limit being in the range of ng/mL. The average LOD value for theprototype ELISA was determined to be 9.2 ng/mL, while the average LOQ value was10.2 ng/mL. We have demonstrated that produced polyclonal antisera are suitable for thedetection of N-protein with affinity and specificity similar to, or better than commercialantibodies. Furthermore, the prototype ELISA can be used with satisfactory confidence forquantification of the N-protein in protein-rich samples, similar to human sera.Abstract: [https://cherry.chem.bg.ac.rs/handle/123456789/5361
Modulation of hepatic inflammation and energy-sensing pathways in the rat liver by high-fructose diet and chronic stress
Purpose High-fructose consumption and chronic stress are both associated with metabolic inflammation and insulin resistance. Recently, disturbed activity of energy sensor AMP-activated protein kinase (AMPK) was recognized as mediator between nutrient-induced stress and inflammation. Thus, we analyzed the effects of high-fructose diet, alone or in combination with chronic stress, on glucose homeostasis, inflammation and expression of energy sensing proteins in the rat liver. Methods In male Wistar rats exposed to 9-week 20% fructose diet and/or 4-week chronic unpredictable stress we measured plasma and hepatic corticosterone level, indicators of glucose homeostasis and lipid metabolism, hepatic inflammation (pro- and anti-inflammatory cytokine levels, Toll-like receptor 4, NLRP3, activation of NF kappa B, JNK and ERK pathways) and levels of energy-sensing proteins AMPK, SIRT1 and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha). Results High-fructose diet led to glucose intolerance, activation of NF kappa B and JNK pathways and increased intrahepatic IL-1 beta, TNF alpha and inhibitory phosphorylation of insulin receptor substrate 1 on Ser(307). It also decreased phospho-AMPK/AMPK ratio and increased SIRT1 expression. Stress alone increased plasma and hepatic corticosterone but did not influence glucose tolerance, nor hepatic inflammatory or energy-sensing proteins. After the combined treatment, hepatic corticosterone was increased, glucose tolerance remained preserved, while hepatic inflammation was partially prevented despite decreased AMPK activity. Conclusion High-fructose diet resulted in glucose intolerance, hepatic inflammation, decreased AMPK activity and reduced insulin sensitivity. Chronic stress alone did not exert such effects, but when applied together with high-fructose diet it could partially prevent fructose-induced inflammation, presumably due to increased hepatic glucocorticoids
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