252 research outputs found
Simulation of a classical swine fever outbreak in rural areas of the Republic of Serbia
Several different strategies for control and eradication of classical swine fever (CSF) were compared using a Monte Carlo method-based simulation model. The control strategy analysed in this paper, in addition to other CSF control measures, includes application of biosecurity measures on pig farms and rural backyard holdings. Elements of the control strategy are based on applicable regulations and include the simulation of detection of the disease, setting up the protected and surveillance zones, standstill of pig movements and restricted movement of animals, vehicles, equipment, and people with strong control measures in protection and surveillance zones, euthanasia of susceptible pigs, protective vaccination of pigs, compensation etc. During the simulation, different output parameters were compared such as: duration of epidemic of a disease, number of affected holdings and animals, direct costs such as those for dead or culled animals, costs of surveillance, disposal of infectious materials, cleaning and disinfection. Depopulation of affected animals with early diagnostics and vaccination in the protection and surveillance zone proved to be the most effective measures to stop the spread and for the eradication of the disease. Moreover, during the simulation, systematic implementation of biosecurity measures in all pig production clusters was demonstrated to be an appropriate strategy for sustainable control of CSF and the establishment of a stable epidemiological situation
Fotosenzibilizovana oksidacija lipida u rastvoru indukovana kontinualnim UV-stresom u prisustvu kvercetina
The aim of the present PhD thesis was to study UV(-A and -B)
induced lipid peroxidation sensitized by synthetic (benzophenone)
and endogenous photosensitizers (bilirubin, riboflavin) in the
presence of quercetin as antioxidant. Phospholipid mixure was used
as a ”protective target” and the whole process was followed in the
simplest possible system – methanolic solution.
Photodegradation of sensitizers and quercetin with the consequent
occurrence of their degradation products both individually and in the
mutual mixture, as well as in the mixture with phospholipids (where
beside the mentioned processes peroxides production occurs), was
followed by RP-HPLC chromatography. Unambiguous identification
of degradation products was enabled by UHPLC-ESI-MS technique
while free radical species were identified by EPR spectroscopy.
Benzophenone was photostabile, photodegradation of bilirubin gave
biliverdin and dipiroles while main degradation products of riboflavin
were lumichrome and lumiflavin. Insight into the mechanism and
control of lipid peroxidation provided ”conjugated diene” assay, by
following the signal at 234 nm (the absorption maximum of
conjugated diene structures). As typical Type I sensitizer,
benzophenone generated superoxide radical anion, while riboflavin
generated both superoxide and singlet oxygen by mixed Type I and II
mechanisms. Irradiation of bilirubin-riboflavin mixture showed, in the
indirect way, that bilirubin is typical Type II sensitizer.
Photosensitizing capability of the studied sensitizers decreases in the
order: riboflavin > benzophenone > bilirubin. Quercetin exhibited
efficient antioxidant activity, mediated by its own degradation, in
terms of its preventive (absorbing UV radition), chain-breaking
activities (scavenging of generated superoxide radical anion, singlet
oxygen and lipid peroxides) and besides all this effectively quenched
triplet exited states of sensitizers (first of all benzophenone and
riboflavin)
Damage tolerance analysis of structural components under general load spectrum
In this investigation fatigue behaviour of damaged structural components under cyclic loads constant amplitude and load spectrum is considered. Primary attention of this investigation is the establishment of computation procedure for the evaluation of the residual life of aircraft attachment lug type structural elements in the presence of initial cracks. In this investigation for residual life estimation and crack growth analysis Strain Energy Density ( SED) method is used. The SED method uses the low-cycle fatigue (LCF) properties of the material in crack growth analysis. In this approach experimentally obtained dynamic properties of the material such as Forman's constants are not required when this method is concerned. The complete computation procedure for the crack propagation analysis using low-cycle fatigue material properties is illustrated with the damaged structural elements. To determine analytic expressions for stress intensity factors (SIF) singular finite elements are used. Results of numerical simulation for crack propagation based on strain density method have been compared with own experimental results
Automatic Synonym Discovery with Knowledge Bases
Recognizing entity synonyms from text has become a crucial task in many
entity-leveraging applications. However, discovering entity synonyms from
domain-specific text corpora (e.g., news articles, scientific papers) is rather
challenging. Current systems take an entity name string as input to find out
other names that are synonymous, ignoring the fact that often times a name
string can refer to multiple entities (e.g., "apple" could refer to both Apple
Inc and the fruit apple). Moreover, most existing methods require training data
manually created by domain experts to construct supervised-learning systems. In
this paper, we study the problem of automatic synonym discovery with knowledge
bases, that is, identifying synonyms for knowledge base entities in a given
domain-specific corpus. The manually-curated synonyms for each entity stored in
a knowledge base not only form a set of name strings to disambiguate the
meaning for each other, but also can serve as "distant" supervision to help
determine important features for the task. We propose a novel framework, called
DPE, to integrate two kinds of mutually-complementing signals for synonym
discovery, i.e., distributional features based on corpus-level statistics and
textual patterns based on local contexts. In particular, DPE jointly optimizes
the two kinds of signals in conjunction with distant supervision, so that they
can mutually enhance each other in the training stage. At the inference stage,
both signals will be utilized to discover synonyms for the given entities.
Experimental results prove the effectiveness of the proposed framework
Nematicidal Activity of Essential Oils on a Psychrophilic Panagrolaimus sp. (Nematoda: Panagrolaimidae)
Essential oils (EOs) have historically been used for centuries in folk medicine, and nowadays they seem to be a promising control strategy against wide spectra of pathogens, diseases, and parasites. Studies on free-living nematodes are scarce. The free-living microbivorous nematode Panagrolaimus sp. was chosen as the test organism. The nematode possesses extraordinary biological properties, such as resistance to extremely low temperatures and long-term survival under minimal metabolic activity. Fifty EOs from 22 plant families of gymnosperms and angiosperms were tested on Panagrolaimus sp. The aims of this study were to investigate the in vitro impact of EOs on the psychrophilic nematode Panagrolaimus sp. in a direct contact bioassay, to list the activity of EOs based on median lethal concentration (LC50), to determine the composition of the EOs with the best nematicidal activity, and to compare the activity of EOs on Panagrolaimus sp. versus plant parasitic nematodes. The results based on the LC50 values, calculated using Probit analysis, categorized the EOs into three categories: low, moderate and highly active. The members of the laurel family, i.e., Cinnamomum cassia and C. burmannii, exhibited the best nematicidal activity. Aldehydes were generally the major chemical components of the most active EOs and were the chemicals potentially responsible for the nematicidal activity
Copper(II) complexes with different diamines as inhibitors of bacterial quorum sensing activity
Three copper(II) complexes, trans-[Cu(1,3-pd)(2)Cl-2]center dot H2O (Cu1; 1,3-pd is 1,3-propanediamine), trans-[Cu(2,2-diMe-1,3-pd)(2)Cl-2] (Cu2; 2,2-diMe-1,3-pd is 2,2-dimethyl-1,3-propanediamine) and trans-[Cu(1,3-pnd)(2)Cl-2]center dot H2O (Cu3; 1,3-pnd is (+/-)-1,3-pentanediamine), were synthesized and structurally characterized by elemental microanalyses, IR, electronic absorption and reflectance spectroscopy and molar conductivity measurements. The antimicrobial efficiency of the complexes against four clinically relevant microorganisms and their antiproliferative effect on the normal human lung fibroblast cell line MRC-5 were evaluated. Since in many bacteria, pathogenicity is regulated by an intercellular communication process called quorum sensing (QS), the effect of the copper(II) complexes Cu1-3 on bacterial QS was examined. The obtained results showed that these complexes inhibited violacein production in Chromobacterium violaceum CV026, indicating their anti-QS activity via the homoserine lactone (HSL) pathway. Two biosensor strains were used to determine which pathway, C4-HSL (N-butanoylhomoserine lactone) or 3OC12-HSL (N-(3-oxododecanoyl) homoserine lactone), was affected by the copper(II) complexes. The biological activities of the copper(II) complexes were compared with those for the nickel(II) complexes of the general formula trans-[Ni(L)(2)(H2O)(2)]Cl-2 (L = 1,3-pd, 2,2-diMe-1,3-pd and 1,3-pnd)
Veterinarski informacioni menadžment sistem (VIMS) u procesu prijavljivanja i menadžmenta zaraznih bolesti
A prerequisite to the development of an efficient animal health, food safety and traceability management system in the animal food production chain is the implementation of an integrated veterinary informational management system (VIMS) capable for the capture, storage, analysis and retrieval of data and providing the opportunity for the cumulative gathering of the knowledge and capability for its competent interpretation. Such a system will enable collecting appropriate data, including quality management and inspection controls, from all establishments and commodities in the 'from farm to fork' food production chain (farms, holdings, slaughterhouses, laboratories, traders etc.) in a structured, predefined format, and facilitate competent analyses and reporting of such data, as well as the improvement of the existing programs and strategies. The role of information system in animal disease diagnosis, surveillance and notification, control of national and international trade of commodities, food safety management, investigation of diseases, predictive microbiology and quantitative risk assessment is of great importance for the quality of veterinary service. Integral part of the VIMS is animal disease notification system designed according to and in compliance with international requirements, standards and recommendation and able to exchange relevant information with similar information systems. The aim of this contribution is to describe national animal disease notification system which is in place in Serbia as a part of VIMS.Preduslov za uspostavljanje efikasnog sistema menadžmenta zdravstvene zaštite životinja, bezbednosti hrane i sledljivosti u lancu proizvodnje hrane je uvođenje integrisanog veterinarskog informacionog menadžment sistema (VIMS) razvijenog na takav način da omogući prikupljanje, čuvanje, analizu i povlačenje podataka i obezbedi kumulativno skupljanje saznanja i njihovu stručnu interpretaciju. Takav sistem će omogućiti prikupljanje podataka, uključujući one iz upravljanja kvalitetom i u okviru inspekcijskih kontrola, od svih objekata u sistemu proizvodnje hrane 'od farme do viljuške' (farme, gazdinstva, klanice, laboratorije, lica koja se bave prometom i dr.) u strukturirano, unapred definisanom obliku, i obezbediti kompetentnu analizu takvih podataka kao i unapređenje postojećih programa i strategija. Uloga informacionih sistema u dijagnostici, nadzoru i prijavljivanju zaraznih bolesti, kontroli unutrašnjeg i međunarodnog prometa, upravljanju bezbednošću hrane, istraživanju žarišta zaraznih bolesti, prediktivnoj mikrobiologiji i kvantitativnoj analizi rizika je od izuzetnog značaja za kvalitet veterinarske službe. Sastavni deo VIMS-a je sistem za prijavljivanje zaraznih bolesti dizajniran prema i u saglasnosti sa međunarodnim zahtevima, standardima i preporukama i osposobljen da vrši razmenu određenih podatka sa sličnim informacionim sistemima. Cilj ovog rada je da se opiše nacionalni sistem za prijavljivanje zaraznih bolesti koji je u Srbiji u primeni kao deo VIMS-a
Transport Properties of Spin Field-Effect Transistors Built on Si and InAs
Abstract We investigate the properties of ballistic spin fieldeffect transistors (SpinFETs). First we show that the amplitude of the tunneling magnetoresistance oscillations decreases dramatically with increasing temperature in SpinFETs with the semiconductor channel made of InAs. We also demonstrate that the [100] orientation of the silicon fin is preferred for practical realizations of silicon SpinFETs due to stronger modulation of the conductance as a function of spin-orbit interaction and magnetic field
Precipitation extremes in the wettest Mediterranean region (Krivošije) and associated atmospheric circulation types
The aim of this paper is to analyse indices of extreme precipitation in Krivošije, Montenegro, the wettest Mediterranean region, from the period 1951–2007 and their relationships with atmospheric circulation using "SynopVis Grosswetterlagen" (SVG) series. Data from two stations were analysed, namely Crkvice (42°34'N and 18°39'E) and Herceg Novi (42°27'N and 18°31'E). Four indices of precipitation extremes (SDII, R75p, R95p, R95pTOT) were assessed including number of dry days. The results suggest that the number of days with precipitation decreased. To analyse the relationship between extreme precipitation events and circulation types we have used an efficiency coefficient (<i>E</i><sub>c</sub>). Regarding relation to atmospheric circulation, westerly, southwesterly and northwesterly circulation types with anticyclonic features over Central Europe are more frequent for dry days (days with <i>R</i><1.0 mm) and northerly, easterly and southerly types for wet and very wet days (R75p and R95p indices). The types with cyclonic condition over Central Europe show a large proportion of wet and very wet days. Also, activity of Genoa cyclogenesis and orographic influence over a small area are the main reasons for the high precipitation amounts recorded in the Krivošije region (Crkvice)
Some achievements in RBIM implementation according to RIMAP approach
Some results of RIMAP based RBIM implementation on the example of 21 000 components in refinery Pancevo are presented in this paper. It is proved to be a powerful tool for maintenance planning, for increasing industrial safety and decreasing inspection and maintenance costs by 25%. Changes in Serbian regulations for pressure vessels were adopted
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