Vpliv različnih tehnoloških postopkov predelave grozdja sorte Zelen (Vitis vinifera L.) na aromatične značilnosti vinaFranko Fabjan
Opis: Poleg sorte, geo-klimatskih pogojev in vinogradniških strategij v vinogradu so tudi vinarjeve odločitve glede izbora vinifikacijskih postopkov tiste, ki lahko odločilno vplivajo na končno kakovost vina, vključno z njegovimi aromatskimi značilnostmi. Z različnimi prijemi ali postopki pred alkoholno fermentacijo in med njo lahko vplivamo predvsem na ekstrakcijo in ohranitev primarnih ter na tvorbo sekundarnih aromatskih spojin.
V okviru diplomskega dela smo s pomočjo modernih analitskih pristopov metabolnega profiliranja in tehnike GC/MS/MS preučevali vpliv različnih tehnoloških postopkov predelave grozdja (krioekstrakcija s suhim ledom, stik s celimi jagodami med fermentacijo, klasični pristop-kontrola) na vsebnost prostih in vezanih aromatičnih spojin v mladih vinih Zelen, letnik 2014. Preučili smo tudi vpliv obravnavanih tehnologij na senzorične lastnosti, vezane na zaznave vonja v mladih vinih.
Rezultati enoletnega poskusa so nakazali, da lahko s pomočjo krioekstrakcije v vinih Zelen povečamo izplene skupnih prostih aromatičnih kislin, estrov in terpenov, po drugi strani pa smo zaznali le trend povečanja vsebnosti skupnih višjih alkoholov pri vzorcih iz postopka dodajanja jagod med fermentacijo.
V primeru vezanih aromatskih spojin smo s pomočjo postopka dodajanja jagod v primerjavi s kontrolo opazili trende povečanja vsebnosti nekaterih vezanih estrov, norizoprenoidov in višjih alkoholov, krioekstrakcija pa je večinoma povzročila trende k niţjim vsebnostim vezanih aromatskih spojin glede na kontrolne vzorce.
Nazadnje so se tudi senzorična opazovanja z vonjem povezanih lastnosti vin zaključila preteţno v prid postopku z dodajanjem jagod med fermentacijo.
Ključne besede: 'Zelen' (Vitis Vinifera L.), alternativni pristopi v predelavi grozdja, krioekstrakcija, dodajanje sveţih jagod med alkoholno fermentacijo, proste aromatične spojine v vinu, vezane aromatične spojine v vinu, senzorika vina
Objavljeno: 23.01.2017; Ogledov: 516; Prenosov: 39
Ogledov v tednu: 62
EFFECT OF DIFFERENT LOADING CONCENTRATIONS OF Cu AND Zr METAL IONS ON PHOTOCATALYTIC ACTIVITY OF P25Ikram Muhammad
Ključne besede: odpadne vode, degradacija, ki onesnažuje, organska predhodniki, TiO2 photocatalysis, fotokatalitsko aktivnost, Zr in Cu dopantov, superoksid anioni, hidroksilni radikal, metilen modro
Objavljeno: 06.02.2017; Ogledov: 316; Prenosov: 31
Ogledov v tednu: 61
NOVEL METHODS FOR DETECTION AND REMOVAL OF POLLUTANTS FROM WATERSFranja Prosenc
Opis: Water security and quality are a global issue of concern, which have recently become alarming due to the growth of the human population, industrialisation and expanded agricultural activities. Biologically active compounds, such as pharmaceuticals and personal care products can have major adverse effects on aquatic organisms, and are therefore one of the biggest threats in water quality. Another major concern is the spread of waterborne pathogens, including multidrug resistant (MDR) bacteria, which can cause serious illnesses in humans. In order to maintain water abundance and quality, it is necessary that adequate wastewater treatment and analytical techniques allowing for sensitive and fast-response detection of water hazards are in place.
Conventional (waste)water treatment technologies often fail to adequately remove all of the water hazards detailed above. Moreover, conventional analytical techniques currently used in water quality control are, although highly selective and sensitive, time-extensive, with throughput of merely 2 to 3 samples per hour, excluding the time for sample preparation. With respect to these drawbacks, research was proposed to explore new approaches for degradation of recalcitrant compounds, inactivation of microorganisms, and fast screening methods, which are listed in the second chapter of this dissertation as research objectives.
In the third chapter, an extensive theoretical background on the hazards found in aquatic environment, namely pharmaceuticals and waterborne pathogens, is given. Pharmaceuticals enter the environment through several routes (disposal of unused medication via the toilet, pharmaceuticals passing through the human body unchanged/slightly transformed, animal excretions of pharmaceutically active compounds, insufficient wastewater treatment, etc.); therefore, traces of pharmaceuticals have repeatedly been reported in surface waters, groundwater, wastewater effluents, and even drinking water. Iodinated contrast agents (ICAs), as the compounds of interest in this project are further described. ICAs are eliminated from the human body practically unchanged; therefore a large proportion of them end up in municipal and hospital wastewater, where they can be present in concentrations of up to 2.4 g/L. Their ecotoxicity, degradation attempts, as well as detection monitoring in the environment are reviewed within the chapter. Additionally, waterborne pathogens, which account for 2.2 million deaths per year, are reviewed in this chapter, with emphasis on multidrug-resistant (MDR) bacteria. Although MDR infections are mostly prevalent in hospital environments, the presence of MDR bacteria in the environment is not a rarity. A high percentage of bacterial isolates in waters have been shown to be of an MDR phenotype. The theoretical background in analytical methods in water quality monitoring is also given in this chapter. Vanguard and rearguard techniques are explained, the first offering simple, cheap, and rapid sample screening, but sacrificing sensitivity and selectivity, whereas the second providing the highest quality information, excellent sensitivity and selectivity, but in expense of complicated and timely sample handling and high-cost instruments. By combining the two techniques the benefits of both can be exploited in a single system. The basic principles of thermal lens spectrometry (TLS) and its miniaturised version - the thermal lens microscopy (TLM) as fast screening methods providing high sensitivity are further explained, and their practical applications are reviewed. Furthermore, composite materials have recently been finding applications in water treatment technologies, as filter materials, adsorptives for pollutants, catalysts for degradation reactions, and disinfectants. The applications of three main types of composites: synthetic composites, biocomposites, and nanocomposites, are also reviewed within this chapter.
The core of this dissertation is presented in the fourth and the fifth chapter, which examine two separate approaches for water treatment, as well as analytical methods for fast screening purposes. The fourth chapter is investigating options for degradation of iodinated X-ray agents (ICAs), namely diatrizoate, through biodegradation with extracellular enzymes of white rot fungus Dichomitus squalens, and chemical oxidation with manganese(III) acetate. Enzymatic degradation with laccase (Lac) and manganese peroxidase (MnP) at low enzymatic activities was unsuccessful, whereas at approximately 3-times higher activities the enzymes were capable of 60 % degradation in 12 days. Chemical oxidation of diatrizoate with manganese(III) acetate resulted in 85 % degradation in 12 days. Moreover, the suitability of microfluidic flow injection analysis coupled with thermal lens microscopy (μFIA-TLM) as a fast screening method for diatrizoate degradation was examined. The degradation was monitored through the release of iodide from the diatrizoate molecule. μFIA-TLM proved to be a preferable method over UV-Vis spectrophotometry, due to its higher sensitivity, sample throughput, and simple sample handling. Limit of detection (LOD) for μFIA-TLM method was estimated to be 0.14 µM in a 100 µm channel, which is 9 times lower than LOD obtained in UV-Vis measurements. In addition to μFIA-TLM and UV-VIS, high-pressure liquid chromatography (HPLC) was used to monitor the remaining parent compound in the reaction mix.
In the fifth chapter, the second water treatment approach is described. This includes synthesis of biocomposite materials from cellulose (CEL) and keratin (KER), with metal (Ag0, AgCl, Au0) nanoparticles (NPs). Materials were characterised for presence, species, and size of NPs with X-ray diffraction (XRD) and with scanning electron microscopy (SEM). Nanoparticles were confirmed to be of expected species, with sizes as follows: 6.3 ± 0.5 nm for Au NPs, 12 ± 2 nm for Ag NPs, and 22 ± 1 nm for AgCl NPs. In order to evaluate antibacterial properties of the materials, contact tests with gram-negative (Escherichia coli and Pseudomonas aeruginosa) and gram-positive bacteria (Staphylococcus aureus, Methicillin-resistant S. aureus (MRSA), and Vancomycin-resistant Enterococcus faecalis (VRE)) were conducted. Direct-contact assay over 24 hours showed a dose and species-dependent antibacterial activity of [CEL:KER + Ag NPs] materials. The highest potency against the selected bacteria (up to 6-log of reduction) was observed for the material with 500 mg of Ag NPs. AgCl NPs appeared to be less potent than Ag NPs, whereas Au NPs exhibited antibacterial activity only against MRSA and VRE. In addition, antiviral properties of materials were investigated on selected bacteriophages (MS2, phiX174, and fr). However, biocomposite materials with 500 mg of Ag NPs and AgCl NPs, as well as, 240 mg of Au NPs did not exhibit any activity against selected bacteriophages. Biocompatibility with human fibroblasts was evaluated through a direct contact assay for 3 and 7 days of exposure. High concentrations of metal NPs turned out to be cytotoxic for human fibroblasts, whereas the amount of 69 mg of Ag NPs in [CEL:KER] was low enough not to affect the viability of the fibroblasts after 3 days of exposure. Composites with Ag NPs and AgCl NPs were also tested for leachability of NPs out of the materials. Both types of NPs were leaching out in two different forms, as silver ions, and as colloidal silver. Leaching of ionic silver from both materials stabilised after 3 days, whereas colloidal silver was still leaching out on the 7th day. The overall percentage of the total silver (ionic + colloidal) leached was only 0.04 % of silver incorporated in the material.
In summary, this dissertation investigates alternative approaches for water treatment technologies, which could potentially serve as unit improvements of existing technologies, or as on-point pre-treatment technologies to facilitate further conventional water treatment techniques. It also demonstrates the suitability of μFIA-TLM for fast screening measurements in aquatic samples, offering high sample throughput, simple handling of the samples and superior sensitivity over the UV-Vis spectrophotometry.
Ključne besede: Antibacterial biocomposites, nanomaterials, water treatment technologies, multidrug-resistant bacteria, iodinated contrast agents, thermal lens microscopy, flow-injection analysis, microfluidics
Objavljeno: 26.04.2017; Ogledov: 186; Prenosov: 8
Ogledov v tednu: 53
Cortisol fetal fluids and newborn outcome in term pregnancy small-sized purebred dogs.Barbara Bolis
, Tanja Peric
, Alessandro Rota
, Massimo Faustini
, Maria Cristina Veronesi
Opis: In order to provide further information about canine perinatology, and because of the scarce
knowledge about fetal fluids composition in dogs, the present study was aimed to assess the cortisol
concentrations in fetal fluids collected from small-sized purebred newborn puppies born by elective
cesarean section, at term of pregnancy (Meloni et al, 2014). Furthermore we
assessed possible correlations of amniotic and allantoic cortisol concentrations and newborn outcome
at 24 hours of age and with the newborn gender. Fetal fluids cortisol concentrations were also
evaluated for correlation with maternal parity, litter-size, neonatal gender, birth weight and Apgar score
(Veronesi et al, 2009). The study, performed on 50 born alive, normal weighed puppies, without gross
physical malformation, showed that cortisol concentration was higher in allantoic than in amniotic fluid
(p<0.01), even if a strong positive correlation between the two fluids cortisol concentration was found
(p<0.0001; R=0.83). Interestingly, higher amniotic (p<0.05) cortisol concentrations were associated to
puppies not surviving at 24 hours after birth. Therefore it could be suggested that this parameter may
be useful for the recognition, at birth, of puppies needing special surveillance in the first day of age. In
relation to the other evaluated parameters, no correlations with amniotic or allantoic cortisol
concentrations were found. In conclusion, the present results showed that in small-sized purebred
puppies, born at term by elective caesarean section, the evaluation of amniotic cortisol concentration
seems useful for the detection of puppies that need special surveillance during the first 24 hours of age,
and should be coupled to the newborn evaluation by Apgar score.
Ključne besede: cortisol, fetal fluids, pregnancy, dog
Objavljeno: 12.05.2017; Ogledov: 96; Prenosov: 3
Ogledov v tednu: 52
Tantadrujevo iskanje sreče: od didaktike do interpretacijeZoran Božič
Opis: Članek obravnava primer šolske interpretacije srednje dolgega pripovednega besedila, in sicer po načelu učne verige odlomkov z vprašanji za tesno branje. Ta didaktični pristop se je sicer na Slovenskem uveljavljal že pred drugo svetovno vojno, bolj sistematično uresničitev pa je doživel z izidom delovnih zvezkov za domače branje Zlati poljub in Poljub zlata leta 1998. Po skoraj dveh desetletjih šolske rabe je čas za natančnejšo presojo pristopa oz. njegove uporabnosti, tudi s pomočjo primerjave dveh učnih verig, nastalih po znani Kosmačevi noveli Tantadruj. Članek zaključuje interpretativni poskus, ki Tantadrujevo iskanje sreče povezuje s pripovedovalčevim iskanjem ustvarjalnega navdiha.
Ključne besede: Ciril Kosmač, učna veriga, tesno branje, domače branje, didaktika književnosti
Objavljeno: 09.05.2017; Ogledov: 78; Prenosov: 0
Ogledov v tednu: 45
THE AUTOBIOGRAPHICAL EXPERIENCE OF MIGRATION IN THE LITERARY WORKS OF WOMEN WRITERS OF THE SLOVENIAN LITERARY POLYSYSTEMMegi Rožič
Opis: People have travelled and migrated since the early periods of history and the phenomenon of migration, defined as “the movement of large numbers of people, birds or animals from one place to another” (Oxford Advanced Dictionary, 7th ed.) has a history of hundreds of years (Pourjafari, Vahidpour, 2014) and is by no means new. But the way of travelling, migrating and mobility in contemporary reality does have many specific aspects and recently it has been studied in new ways, with new concerns. The experience of migration in the contemporary world is a fundamental characteristic of human societies. “It is a system in which the circulation of people, sources and information follows multiple paths. The energy and barriers that alter the course or deflect the contemporary patterns of movement have both obvious and hidden features. While nothing is utterly random, the consequences of change are often far from predictable” (Papastergiadis, 2000: 1). This unpredictability and multidirectionality has led to changes in approaches to the study of migration in recent decades. In the last few decades the study of migration has increasingly been accompanied by a tendency to study it on the individual level − at the level of personal life stories (Milharčič Hladnik, 2007). These are also markedly expressed in the medium of literature.
The present dissertation presents literary oeuvres of seven women writers, who thematise the autobiographical experience of migration, it offers an individually, woman-centred experience and view of migration. In selected oeuvres personal views are expressed on that experience, different strategies of coping with life in new realities and regarding relationships in these environments. The thematisation of the experience of migration in selected oeuvres is also connected with a problematisation of other concepts: the concepts of belonging, borders, nation-state, culture and language. It is also vitally connected with the personal identity construction of the lyrical subjects and literary characters and also because of the autobiographical character of selected literary works of the literary artists themselves. The experience of migration in selected literary works leads to unique identity formations, which in themselves combine elements of different cultural backgrounds and traditions. In their literary works these selected women writers also shape their relationship toward time and space dimensions, tradition and interpersonal relationships through the experience of migration.
The experience of migration, the relocation of the subject and a change of the geographical area in selected oeuvres, does not only represent a change of the geographical position: it also allows a deviation from other rigid and seemingly fixed and unvarying patterns and virtual realities that accompany human life. Migration can also present an alienation effect from traditionalisms and determinants that define human lives. In the literary oeuvres of these selected women writers, migration is only in part tied to the traditional concepts related to migrants, with the loss of roots and rupture with the place of origin. In the selected literary oeuvres, migrants are rarely considered to be uprooted and unable to find their anchor or confidently start a new chapter in their lives in a new environment. Migration is mostly connected with the possibility of expanding the horizon of insights and perspectives of looking at life, with the acceptance of its complexities, ambiguities and incompleteness. Mostly, the experience of migration is seen as a new, creative option, which opens and examines the wide range of other issues and dilemmas. The condition of uprooted loss has traditionally negative connotations, but in the selected oeuvres vagueness and fluidity allow a real insight into the real, complex nature of life and human existence.
Ključne besede: The experience of migration, women writers, Maruša Krese, Ifigenija Zagoričnik Simonović, Brina Švigelj-Mérat − Brina Svit, Gabriela Babnik, Stanislava Chrobáková Repar, Erica Johnson Debeljak, Lidija Dimkovska, literary polysystem, nomadic entity, locational feminism, fluid identity, transnationalism, transculturalism
Objavljeno: 11.10.2016; Ogledov: 663; Prenosov: 191
Ogledov v tednu: 40