408 research outputs found
Contribution to studies on white-tailed eagle (Haliaeetus albicilla Linnaeus, 1758) in Western Serbia and the Republic of Srpska
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A test to detect association between autosomal and sex-linked loci in random mating populations: an example with Drosophila melanogaster
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The possibility of obtaining beta-anhydrite from waste nitrogypsum
The possibility of obtaining β - anhydrite from nitrogypsum, which is waste from a nitrocellulose plant, was investigated. It was shown by means of qualitative IR analysis that the product obtained by heating nitrogypsum for 5 hours at 700 o C was â - anhydrite. When the β- anhydrite was mixed with water at a W/S (water/solid) ratio of 0.54 in presence of different accelerators (CaO, mixture CaO - ash, ash, Na2SO4 and K2SO4), pastes were formed which hardened on standing. The compressive strength of the hardened samples was measured after 7 and 28 days and their composition determined by qualitative IR analysis. On the basis of these results, it was observed that a relationship exists between the composition (depending on the used accelerator) and the compression strength of the samples. Namely, the formation of large cores of double salts: syngenite (K2SO4 ⋅CaSO4 ⋅H2O) and glauberite (Na2SO4 ⋅CaSO4), in the presence of the accelerators K2SO4 and Na2SO4, respectively, was due to the rapid and complete crystallization of the dihydrate (CaSO4 ⋅2H2O). This fast crystal growth of the dihydrate resulted in high compressive strengths of these samples. In the other samples (prepared in presence of the accelerators: CaO, mixture CaO - ash and ash), dihydrate did not form and, consequently, their compressive strength was low
Analysis of antioxidative status of human milk of mothers of preterm infants
Prevremeno rođena deca su posebno ugrožena zbog skromnijeg antioksidativnog potencijala u kombinaciji sa većom izloženošću oksidativnom stresu. Naime, oksidativni stres izazivaju visoke koncentracije kiseonika, fototerapija i intravenska primena lipida koji su deo nužnog terapijskog pristupa ovoj populaciji dece, kao i učestale infekcije.
Humano mleko (HM) predstavlja složeni biološki fluid koji ima antioksidaciona svojstva. Antioksidativni enzimi prisutni u HM su superoksid dismutaza (SOD), katalaza (CAT), glutation peroksidaza (GSH-Px) i glutation reduktaza (GR). Neenzimski antioksidansi u HM su vitamin C, E, beta-karoten, glutation, laktoferin, koenzim Q, beta-endorfini i drugi. Ishrana humanim mlekom kod prevremeno rođene dece ima važnu ulogu u prevenciji oksidativnog stresa.
Cilj: Određivanje ukupnog antioksidativnog kapaciteta (UAK) mleka majki prevremeno rođene dece tokom laktacije (kolostrum, prelazno i zrelo mleko). Određivanje UAK zrelog svežeg HM i poređenje sa zrelim HM koje je termički obrađeno (skladištenjem u frižideru, zamrzavanjem ili pasterizacijom ), sa HM u koga je dodat obogaćivač, kao i adaptiranom mlečnom formulom za ishranu prevremeno rođene dece. Upoređen je i antioksidativnni status zrelog obogaćenog mleka i adaptirane mlečne formule za ishranu prevremeno rođene dece.
Materijal i metode istraživanja: Ova kohortna studija je obuhvatila 30 majki prevremeno rođene dece (porođaj pre 37. gestacijske nedelje), kod kojih je uspostavljena laktacija, prema redosledu prijema u Institut za neonatologiju u Beogradu, u periodu od 01.12.2014. do 31.05.2016. Uzorci HM su od svake majke uzimani tri puta. Naime UAK je određivan u svežem HM uzorkovanom u prva 3 dana nakon porođaja (kolostrum), zatim od 5-14. dana nakon porođaja i u zrelom HM uzorkovanom nakon 21. dana od porođaja. Kriterijum za isključivanje iz studije je bio prekidanje laktacije, potreba za primenom terapije koja je kontraindikovana za vreme laktacije, kao
i pušenje duvana...Preterm infants are especially exposed to oxidative stress because of poorer antioxidative defense mechanism. Oxidative stress is induced by frequent infections, as well as by high oxygen concentrations, phototherapy and intravenous lipid infusions, all of which are part of necessary therapy in this population of children.
Human milk (HM) represents a complex biological fluid with antioxidative properties. Antioxidative enzymes of HM are superoxide-dismutase (SOD), catalase (CAT), glutathione-peroxidase (GSH-Px), glutathione-reductase (GR). Non enzyme antioxidants in HM are vitamin C, vitamin E, beta-carothen, glutathione, lactoferrin, coenzyme Q, beta-endorphins, and others. Human milk nutrition in preterm infants has an important role in prevention of oxidative stress.
Goal: Determination of total antioxidant capacity (TAC) of milk of mothers of preterm infants during lactation period (colostrums, early milk, mature milk). TAC of mature fresh milk is determined and compared with milk exposed to thermal processing (refrigeration, freezing or pasteurization), with fortified HM, and preterm milk formula. Antioxidative status of mature fortified milk and preterm milk formula was also compared.
Material and methods: This cohort study included 30 mothers of preterm infants (delivery before 37 weeks of gestation), with lactation according to admission in Institute for neonatology, during the period from December 1st 2014. to May 31st 2016. Sample of HM were collected from each mother three times. The TAC was determined in fresh HM collected in the first 3 days after delivery (colostrum), then between days 5 and 14 after the delivery, and in mature HM after 21 days from the delivery. Criteria for exclusion were cessation of lactation, need for therapy contraindicated during breast feeding and smoking. Determination of TAC in HM was performed by different non-enzyme: spectrophotometric (ability of catching DPPH radicals, determination of total phenol content with Folin-Ciocaletu reagent, method based on antioxidant reaction with Fe (III)-complex, inhibition of lipid peroxidation), electrochemical (cyclic and pulse
voltametry), fluorimetric methods (method of determining antioxidative capacity of absorbing oxygen radicals – ORAC), and electron paramagnetic resonant spectroscopy..
Study of a long term processes in d.c. argon arc plasma by square power modulation with variable low current period
U-shaped d.c. argon stabilized arc with aerosol supply was investigated by current modulation between 9 and 3 A level and low current period lasting from 0.05 to 40 ms. The variable low current period has great influence on delayed line intensity response that provides information about a recombination and transport processes in plasma. The obtained results indicate that plasma slowly reaches stationary state and that processes related to changes in atom concentration play important role. Character of temporal responses strongly depends on first ionization energy of analyte.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200
The examination of the refreshing drink whey production possibility at aseptic conditions
Kemijski sastav i biološka vrijednost surutke ukazuju da se ona može višestruko koristiti. Međutim, surutka se u našoj zemlji još najčešće suši i koristi za animalnu ishranu. Ova istraživanja su vršena sa ciljem dobijanja osvježavajućih napitaka od surutke. Izvršenim istraživanjima je utvrđeno da termički tretman hitno ne utječe na promjenu fizičko-kemijskog sastava i nutritivne vrijednosti napitka od surutke. Zatim, da je tehnološki postupak proizvodnje jednostavan i siguran, a provedenim degustacijama je utvrđeno da najbolje karakteristike posjeduje napitak sa dodatkom naranče.Investigations were carried out in order to find out the process of whey drinks. Physico-chemical, microbiological and organoleptical qualities of the products were controlled during 6 weeks
The examination of the refreshing drink whey production possibility at aseptic conditions
Kemijski sastav i biološka vrijednost surutke ukazuju da se ona može višestruko koristiti. Međutim, surutka se u našoj zemlji još najčešće suši i koristi za animalnu ishranu. Ova istraživanja su vršena sa ciljem dobijanja osvježavajućih napitaka od surutke. Izvršenim istraživanjima je utvrđeno da termički tretman hitno ne utječe na promjenu fizičko-kemijskog sastava i nutritivne vrijednosti napitka od surutke. Zatim, da je tehnološki postupak proizvodnje jednostavan i siguran, a provedenim degustacijama je utvrđeno da najbolje karakteristike posjeduje napitak sa dodatkom naranče.Investigations were carried out in order to find out the process of whey drinks. Physico-chemical, microbiological and organoleptical qualities of the products were controlled during 6 weeks
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