Ispitivanje efikasnosti različitih tretmana subkliničkih mastitisa krava izazvanih Staphylococcus aureus-om u zasušnom periodu

Mastitis is still the most common disorder which is present in diary cows. Changes in genetics, nutrition and milking equipment affect the incidence of subclinical and clinical forms of mastitis. Staphylococcus aureus is the causative agent of subclinical and clinical forms of mastitis. In the acute form it can cause malignant mastitis in the form of granulomatous and necrotic changes. Chronic forms of staphylococcal mastitis often develop as subclinical changes. Halting the entrance, the colonization and replication of the pathogen into the udder impose the constant need for regular milk controls and preventive and therapeutic measures in order to decrease the incidence of mastitis. A modern approach in the eradication and control of mastitis is immunoprophilaxis, aimed towards the innovation of new vaccines against the most common causes of mastitis. In this study we have applied the vaccine prepared with S. aureus isolated from milk taken from the experimental farm and the referent capsular strain. The vaccine was applied twice two months before calving in a dose of 5mL. The vaccine contained inactivated S. aureus JR3 bacterial cells in a quantity of 1 x 1010 cfu/mL and 5 mg SM capsule S. aureus 2286 strain. After vaccination of cows in late pregnancy, subclinical mastitis appears at a smaller frequency compared to the three experimental groups. To the first group of cows the antibiotic was applied intramammary, to the second group antibiotics were applied parenterally and intramammary and the third group served as the untreated control.Mastitis je još uvek najučestalije i 'najskuplje' obolenje na mlečnim farmama. Promene u genetici, ishrani, aparatima za mužu i načinu držanja krava utiču na učestalost pojave subkliničkih i kliničkih mastitisa. Staphylococcus aureus izaziva subkliničke i kliničke forme mastitisa, koje mogu u akutnoj formi da izazovu teške, maligne mastitise u vidu granulaomatoznih i nekrotičnih promena. Hronične forme stafilokoknog mastitisa uglavnom prolaze kao subklinički oblici obolenja mlečne žlezde. Sprečavanje prodora patogenog uzročnika u mlečnu žlezdu, njegovo naseljavanje i razmnožavanje, nameću stalnu potrebu za redovnim kontrolama mleka kao i preduzimanje preventivnih i terapijskih mera u cilju smanjenja nastanka mastitisa. Moderan pristup suzbijanju i kontroli mastitisa je imnunoprofilaksa koja je usmerena na pronalaženje efikasnih vakcina protiv nekih najčešćih uzročnika mastitisa. U našem radu koristili smo autohtonu vakcinu koju smo pripremili od S. aureus-a izolovanog iz mleka uzetog sa ogledne farme i referentnog kapsularnog soja S. aureus. Vakcina je dvokratno aplikovana oglednim kravama dva meseca pred telenje u dozi od 5 ml, a sastojala se od inaktivisanih bakterijskih ćelija S. aureus JR3 u količini od 1x1010 cfu/ml i 5 mg SM kapsule soja S. aureus 2286. Nakon dvokratne aplikacije ispitivane vakcine u visokom graviditetu, subklinički mastitisi krava su se pojavljivali u značajno manjem procentu, u odnosu na ostale tri ogledne grupe. Pri tome je jednoj oglednoj grupi krava bio aplikovan antibiotik intramamarno dok su životinjama druge grupe antibiotici bili aplikovani i parenteralno i intramamarno. Treća grupa se sastojala od plotkinja koje nisu bile podvrgnute ni jednom od navedenih tretmana

Imunoprofilaksa mastitisa krava izazvanog sa Staphylococcus aureus

Mastitis in cows represents one of the most actual problems in intensive dairy production. The prevention of pathogen penetration in the udder, its colonization and reproduction impose the constant need for regular milk check-ups, and preventive and therapeutic measures. Staphylococcus aureus causes subclinical and clinical mastitis, which when in the acute form can originate difficult and malignant udder infections with granulomatous and necrotic changes. Chronic forms of Staphylococcal mastitis most often pass as subclinical cases. An efficient commercial vaccine has not been introduced yet, though the application of autochthonous vaccines in the prevention of mastitis can give satisfactory results. In this study we have developed and applied an autochthonous vaccine prepared from S. aureus isolated from milk samples taken from an experimental farm, as well as from the referent capsular strain S. aureus. The vaccine was applied to experimental dairy cattle twice before calving in a dose of 5 mL. It consisted of inactivated bacterial S. aureus JR3 cells in a quantity of 1x1010 cfu/mL and 5 mg SM capsule of the strain S. aureus 2286. This vaccination of dairy cows has resulted in a significant decrease of subclinical and clinical manifested mastitis in the treated group, when compared to the vaccinated group of experimental animals.Mastitisi krava predstavljaju jedan od najaktuelnijih problema u intenzivnoj proizvodnji mleka. Sprečavanje prodora patogenog uzročnika u mlečnu žlezdu, njegovo naseljavanje i razmnožavanje, nameću stalnu potrebu za redovnom kontrolom mleka, kao i preduzimanje preventivnih i terapijskih mera. Staphylococcus aureus izaziva subkliničke i kliničke forme mastitisa, koje mogu u akutnoj formi da izazovu teške, maligne mastitise u vidu granulomatoznih i nekrotičnih promena. Hronične forme stafilokoknog mastitisa uglavnom često prolaze kao subklinički oblici obolenja mlečne žlezde Još uvek nije pronađena komercijalna efikasna vakcina protiv mastitisa izazvanog S. aureus-om, ali primena autohtonih vakcina u preveniranju mastitisa može dati zadovoljavajuće rezultate. Koristili smo autohtonu vakcinu koju smo pripremili od S. aureus-a izolovanog iz mleka uzetog sa ogledne farme i referentnog kapsularnog soja S. aureus. Vakcina je dvokratno aplikovana oglednim kravama dva meseca pred telenje u dozi od 5 ml, a sastojala se od inaktivisanih bakterijskih ćelija S. aureus JR3 u količini od 1x1010 cfu/ml i 5 mg SM kapsule soja S. aureus 2286. Ovaj način vakcinisanja krava protiv mastitisa izazvanog Staphylococcus aureus-om doveo je do smanjenja subkliničkih i kliničkih mastitisa u značajno manjem procentu u odnosu na kontrolnu grupu krava

ELECTRODEPOSITION AND MORPHOLOGY OF COPPER POWDER PARTICLES OBTAINED AT DIFFERENT CURRENT REGIMES

The effect different deposition regimes (constant and reversing currents), on the powdered copper electrodeposits morphology were investigated. The morphology of electrodeposited copper powder was investigated using a scanning electron microscope (SEM). The effect of the current amplitude, cathodic to anodic time ratio and period of the current wave are discussed. It is shown that the parameters determining the reversing current wave determine the micro-morphology of the copper powder particles deposited

Bioaktivne komponente u funkciji oplemenjivanja industrijskog paradajza

Selection of tomato lines for industrial use regarding their nutritional value is a potential that will reflect in the final product obtained from tomato fruits. At the same time, technological process of preparation of tomato juice (100 °C), as well as hot air drying, was studied in order to establish an optimal technological process that is the least disrupting for the natural potential of nutrients contained in fresh fruits. The research was performed on 6 lines and one variety of industrial tomato. The content of vitamin C, vitamin E, lycopene, β-carotene, phenols, flavonoids, dry matter and total antioxidative capacity was studied by applying standard methods for determination of the level of these parameters. Grouping was performed according to traits of average carotenoid content (lycopene, β-carotene), vitamin C, vitamin E, phenols, flavonoids, dry matter and total antioxidative capacity in tomato fruit, by applying PCA. The first two principle components were responsible for 77.18 % of total variability of researched samples. The impact of other five components was low and they were responsible for 22.18 % of the variability. Antioxidative activity was best preserved after finishing, through small losses of lycopene and β-carotene. Losses of vitamin C, vitamin E, phenols and flavonoids during thermal processing were great, mostly in juice, while in dried product, these losses were lower. Nutrient losses were in function of temperature height that the fruits were exposed to during the thermal processing. Genotypes SPRZ and SPSM were marked as the best.Selekcija linija paradajza namenjenog industrijskoj preradi prema osobinama koje definišu njihovu nutritivnu vrednost predstavljaju potencijal koji će se reflektovati u proizvodu dobijenom od plodova paradajza. U isto vreme ispitan je i tehnološki proces pripreme soka paradajza (100 °C) kao i sušenje plodova na toplom vazduhu, kako bi se utvrdio optimalni tehnološki proces koji najmanje narušava prirodni potencijal nutrijenata sadržanih u svežim plodovima. Ispitivanje je sprovedeno na 6 linija i jednoj sorti industrijskog paradajza gde su ispitani sadržaj vitamina C, vitamina E, likopina, β-carotina, fenola, flavonoida, suve materije i ukupni antioksidativni kapacitet, standardnim metodama za utvrđivanje sadržaja ovih parametara. Grupisanje je izvršeno prema osobinama prosečnog sadržaja karetinoida (likopen, β-karoten), vitamina C, vitamina E, fenola, flavonoida, suve materije i ukupnog antioksidatinog kapaciteta u plodu paradajza, pomoću PCA analize. Prve dve principle komponente odgovorne su za 77,18 % ukupne varijabilnosti ispitivanih uzoraka. Uticaj ostalih pet komponenti je mali i one su odgovorne za 22,18 % varijabilnosti. Antioksidativna aktivnost je najbolje očuvana posle dorade kroz male gubitke likopina i β-karotina posle dorade. Gubici vitamina C, vitamina E, fenola, flavonoida pri termičkoj obradi su veliki i to najviše u soku, dok kod sušenog proizvoda ti gubici su nešto manji. Gubici nutrijenata su u funkciji visine temperature kojima su plodovi bili izlagani pri termičkoj obradi. Kao najbolji genotipovi ocenjeni su SPRZ i SPSM

Uticaj strukture čestica na nasipnu masu elektrolitički dobijenog bakarnog praha

The quantitative microstructural analysis and the sieve analysis of copper powder as well as the scanning electron microscopy analysis of the copper powders particles were performed. It was found that the structure of the copper powder particles determines the apparent density of copper powder. The powder particles from the same fractions of different powders occupy approximately the same volume, but the structure of metallic copper is very different. This causes the difference in apparent densities of copper powder obtained under different conditions. The more dendritic is the structure of powder particles the smaller is the apparent density of copper powder.Izvršena je kvalitativna mikrostrukturna i granulometrijska analiza bakarnih prahova kao i analiza morfologije i strukture čestica praha pomoću skenirajuće elektronske mikroskopije (SEM). Ustanovljeno je da struktura čestica praha određuje nasipnu masu bakarnog praha. Čestice iste frakcije različitih prahova zauzimaju otprilike istu zapreminu, ali je struktura metalnog bakra različita. Ovo uzrokuje razlike u nasipnoj masi bakarnog praha dobijenog pod različitim uslovima. Što je struktura čestica više dendritična to je manja nasipna masa bakarnog praha

Uticaj termičke obrade plodova paradajza na antioksidativnu aktivnost, sadržaj vitamina E, suve materije i ukupnih šećera

The objective of this study was the determination of total antioxidant activity, contents of vitamin E, sugar and total dry matter in fresh and thermally processed (dried and juiced) tomato fruits of different selected tomato lines with the aim to establish the nutritive profile and distinguish superior genotypes in order to obtain high-quality final product with more benefit to human health. Content of vitamin E, total antioxidant activity, dry matter and total sugars, in fresh and dried fruits (dried in parallel hot air dryer at 60 °C, until the final product reached the moisture lower than 10% and in tomato juice pasteurized at 100 °C, for 7 minutes) was studied. Comparative trial with 7 genotypes: one commercial variety (SP-109) and 6 selected high inbreeding generation lines (SPP, SPSM, SPRZ, SPRM-20, S-60 and SPO), was set up. Genotype SPRZ had the highest vitamin E content and total antioxidant capacity, both in fresh fruit and after the treatments. Thermal processing by drying at 60°C and pasteurization of tomato changed the level of total sugar and dry matter content. Total antioxidant activity decreased by drying, comparing to fresh fruit while the level of vitamin E decreased in juice pasteurized at high temperature (100 °C). .Cilj istraživanja je određivanje ukupne antioksidativne aktivnosti, sadržaja vitamina E, sadržaja šećera i ukupne suve materije u svežim i termički obrađenim (sušeni plodovi i sok) plodovima različitih selekcionih linija paradajza, sa ciljem utvrđivanja nutritivnog kvaliteta i izdvajanja superiornih genotipova, čijom preradom bi se dobio kvalitetniji krajnji proizvod sa pozitivnim dejstvom na ljudsko zdravlje. Ispitivani su sadržaj vitamina E, ukupna antioksidativna aktivnost, suva materija, i ukupni sadržaj šećera, kod svežih plodova, sušenih plodova (sušenje toplim vazduhom na 60 °C, do konačne vlage uzorka manje od 10%) i soka paradajza (pasterizacijom na 100 °C, u trajanju od 7 minuta). Izveden je komparativni ogled sa 7 genotipova, jedna komercijalna sorta (SP-109) i 6 selekcionisanih linija (SPP, SPSM, SPRZ, SPRM-20, S-60 I SPO) visokih generacija inbridinga. Termička obrada plodova paradajza (sušenjem na 60 °C) i pravljenjem soka dovodi do promene ukupnog sadržaja šećera i sadržaja ukupne suve materije. Ispitivanjem ukupne antioksidativne aktivnosti utvrđeno je da se ona gubi sušenjem u odnosu na svež plod, a sadržaj vitamina E se smanjio u soku koji je dobijen obradom na višim temperaturama (100 °C). Genotip SPRZ imao je najviše vrednosti za sadržaj vitamina E i ukupan antioksidativni kapacitet kako u svežem stanju tako i nakon primenjene obrade. Izborom superiornih genotipova i akumulacijom nutrijenata kroz oplemenjivačke programe, može se poboljšati kvalitet krajnjeg proizvoda i postići dobijanje prerađevina sa većim pozitivnim uticajem na zdravlje ljudi

Pulsed Laser Deposition of BaTiO3 on PVDF substrate

Piezoelectric materials play an important role in development of advanced Micro-electromechanical systems (MEMS) and Nano-electro-mechanical systems (NEMS). Their applications span the aero-space industry, communications, defense systems, national security, health care, information technology and environmental monitoring. Materials used in MEMS/NEMS mustsimultaneously satisfy numerous requirements for chemical, structural, mechanical and electrical properties. Although traditionally MEMS in particular have relied on silicon, the materials used in MEMS/NEMS are becoming more heterogeneous. Taking into account that materials nanostructuring can produce unique mechanical, electrical and piezoelectric properties, in this article the investigation of pulsed laser deposition of BaTiO3 on PVDF substrate has been performed. The titanium-saphire laser operated at 800 nm with 40-fs pulse duration and 1 kHz repetition rate was focused onto a mechanically activated BaTiO3 target. Deposition on PVDF substrate was done at an oxygen partial pressure of 10-7 Torr using a laser pulse frequency of 1 kHz at room temperature. The crystal structure and the microstructure of the films were examined using an X-ray diffractometer and scanning electron microscope, while the surface morphology was observed by atomic force microscopy.It was found that pulsed laser deposition of BaTiO3 on PVDF substrate offers a new set of opportunities for development of advanced flexible piezo-films for the next generation of NEMS

Electrodeposition of iron powder particles of different characteristics

Iron deposits obtained at high current densities and overpotentials are very important from a technological point of view. It has been stated that the open and porous structures of copper or iron deposits obtained at high current densities were ideally suited for use as electrodes in electrochemical devices such as fuel cells, batteries and chemical sensors, while the extremely high surface area is relevant for evaluating some electrochemical reactions. Mainly two types of electrolytes were investigated and these were based on sulfate and chloride electrolytes. With increasing duration of electrolysis, dendrites merge, which is unacceptable for the case of further application. These deposits must be grinded in order to obtain powders. However, in the range of lower acidity the deposits become powdery and, in some cases, may be spongy and sticky. Generally, up to now research indicates that electrodeposition of Fe powders have two steps, deposition of fragile film and grinding. It must be emphasized that we tried and succeeded to obtain Fe powders without grinding process. The aim of this work was to investigate electrodeposition processes of Fe powders from sulfate and chloride electrolytes and morphologies of powder as a function of type of electrolyte and current density.Belgrade, Serbia, June 6-10, 201

Electrodeposition of iron powder particles of different characteristics

Iron deposits obtained at high current densities and overpotentials are very important from a technological point of view. It has been stated that the open and porous structures of copper or iron deposits obtained at high current densities were ideally suited for use as electrodes in electrochemical devices such as fuel cells, batteries and chemical sensors, while the extremely high surface area is relevant for evaluating some electrochemical reactions. Mainly two types of electrolytes were investigated and these were based on sulfate and chloride electrolytes. With increasing duration of electrolysis, dendrites merge, which is unacceptable for the case of further application. These deposits must be grinded in order to obtain powders. However, in the range of lower acidity the deposits become powdery and, in some cases, may be spongy and sticky. Generally, up to now research indicates that electrodeposition of Fe powders have two steps, deposition of fragile film and grinding. It must be emphasized that we tried and succeeded to obtain Fe powders without grinding process. The aim of this work was to investigate electrodeposition processes of Fe powders from sulfate and chloride electrolytes and morphologies of powder as a function of type of electrolyte and current density.Belgrade, Serbia, June 6-10, 201

Povodom stogodišnjice dodeljivanja Nobelovih nagrada - otkrića u hemiji i njihove primene - hemija na granicama fizike i biologije, ili, fizika i biologija na granicama hemije

A survey of the Nobel prizes for chemistry awarded during the 20th century reveals that the development in this science includes breakthroughs in all of its branches, from theoretical chemistry to biochemistry. It is evident a certain dominance for progress in biochemistry, in several areas of organic chemistry, physical chemistry and its subcategories. Chemistry has a position in the center of the sciences, bordering onto physics, which provides its theoretical foundation, on one side, and onto biology on the other, since living organisms are the most complex of all chemical systems. Borders between different areas in chemistry are diffuse, so many contributions of laureates are cited in more than one place. Special attention in the article is devoted to the application of awarded contributions in the large-scale production and industry.Od 1901. kada su prvi put dodeljene Nobelove nagrade za najznačajnija naučna otkrića i pronalaske u fizici, hemiji, medicini sa fiziologijom, zatim za najbolja dela u književnosti, za ostvarenja u borbi za mir, a od 1969.godine i za najvažnije doprinose na području ekonomskih nauka, prošlo je jedno stoleće. Tokom ovog perioda učinjeni su ogromni naučni doprinosi u oblasti fizike, hemije, medicine i fiziologije, pa se mogu, što se tiče ovih nauka, izvesti neki važni zaključci o njihovoj međusobnoj povezanosti i o značaju koje su Nobelove nagrade imale za istraživanja u ovim i srodnim naukama. Sem toga, danas je moguće sagledati kakvu su praktičnu primenu imala otkrića pojedinih nobelovaca, iako je još uvek diskutabilno da li je bolje da kod istraživanja naučnike vodi prvenstveno samo naučno interesovanje, ili istovremeno i ideja o mogućoj tehničkoj primeni nekog otkrića