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New data on distribution of the European pond turtle Emys orbicularis (Linnaeus, 1758) in the Podravje region (NE Slovenia)
Marijan Govedič, Milan Vogrin, Dejan Bordjan, Dominik Bombek, Damijan Denac, Tatjana Gregorc, Franc Janžekovič, Nino Kirbiš, Melita Vamberger, 2016, kratki znanstveni prispevek

Opis: Ten new observations of the European pond turtle Emys orbicularis (Linnaeus, 1758) in the Podravje region are presented. One observation is fairly old, while the others have been made in the last six years. Most of the data are just random observations and do not give a complete overview of the species distribution in the Podravje region. New data suggest that the European pond turtle is more abundant in the Drava River basin than previously known. Distribution and population size of the species in the Drava River basin still remain to be investigated in detail and not only at the Natura 2000 Drava site, especially in the areas of potential habitats prior to planning any new activities.
Ključne besede: European pond turtle, Emys orbicularis, Drava river, Podravje, Slovenia
Objavljeno: 07.08.2017; Ogledov: 69; Prenosov: 3
.pdf Celotno besedilo (363,19 KB)

Duality of terrestrial subterranean fauna
Tone Novak, Matjaž Perc, Saška Lipovšek Delakorda, Franc Janžekovič, 2012, izvirni znanstveni članek

Opis: Terrestrial animals in subterranean habitats are often classified according to their degree of morphological or ecological specialization to the subterranean environment. The commonly held view is that, as distance into a cave increases, the frequency of morphologically specialized, i.e., troglomorphic, species or ecological specialization will increase. We tested this hypothesis for the fauna in 54 caves in Slovenia-the classical land for subterranean biology. We found that there exist two ecologically well separated terrestrial subsurface faunas: one shallow and one deep. 1) The shallow subterranean fauna, adapted to the terrestrial shallow subterranean habitats (SSHs) in the upper 10 m of subsurface strata, is most diverse. It consists of randomly distributed non-troglobionts and a major group of troglobionts adapted to the soil root zone. 2) The deep subterranean fauna is represented by a minor group of troglobionts, adapted to caves. Troglobionts are strictly divided between the two faunas. There is strong evidence that in karstic ecosystems with deep-rooted vegetation this might be a global pattern, or that in these locations only the shallow subterranean fauna exist.
Ključne besede: endemites, superficial subterranean habitats, trogloxenes, troglophiles, troglobionts
Objavljeno: 04.08.2017; Ogledov: 79; Prenosov: 2
.pdf Celotno besedilo (1,94 MB)

Cold tolerance in terrestrial invertebrates inhabiting subterranean habitats
Tone Novak, Nina Šajna, Estera Antolinc, Saška Lipovšek Delakorda, Dušan Devetak, Franc Janžekovič, 2014, izvirni znanstveni članek

Opis: Most organisms are able to survive shorter or longer exposure to sub-zero temperatures. Hypothetically, trogloxenes characterized as not adapted, and troglophiles as not completely adapted to thermally stable subterranean environment, have retained or partially retained their ability to withstand freezing, while most troglobionts have not. We tested this hypothesis experimentally on 37 species inhabiting caves in Slovenia, analyzing their lower lethal temperatures in summer and winter, or for one season, if the species was not present in caves during both seasons. Specimens were exposed for 12 hrs to 1°C-stepwise descending temperatures with 48 hr breaks. In general, the resistance to freezing was in agreement with the hypothesis, decreasing from trogloxenes over troglophiles to troglobionts. However, weak resistance was preserved in nearly all troglobionts, which responded in two ways. One group, withstanding freezing to a limited degree, and increasing freezing tolerance in winter, belong to the troglobionts inhabiting the superficial subterranean habitats. The other group, which equally withstand freezing in summer and winter, inhabit deep subterranean or other thermally buffered subterranean habitats. Data on cold resistance can thus serve as an efficient additional measure of adaptation to particular hypogean environments.
Ključne besede: endemites, superficial subterranean habitats, trogloxenes, troglophiles, troglobionts
Objavljeno: 04.08.2017; Ogledov: 44; Prenosov: 3
.pdf Celotno besedilo (358,59 KB)

Vesiculation of biological membrane driven by curvature induced frustrations in membrane orientational ordering
Dalija Povše Jesenek, Šárka Perutková, Wojciech Góźdź, Veronika Kralj-Iglič, Aleš Iglič, Samo Kralj, 2013, izvirni znanstveni članek

Opis: Membrane budding often leads to the formation and release of microvesicles. The latter might play an important role in long distance cell-to-cell communication, owing to their ability to move with body fluids. Several mechanisms exist which might trigger the pinching off of globular buds from the parent membrane (vesiculation). In this paper, we consider the theoretical impacts of topological defects (frustrations) on this process in the membranes that exhibit global in-plane orientational order. A Landau–de Gennes theoretical approach is used in terms of tensor orientational order parameters. The impact of membrane shapes on position and the number of defects is analyzed. In studied cases, only defects with winding numbers m = ±1/2 appear, where we refer to the number of defects with m = 1/2 as defects, and with m = –1/2 as anti-defects. It is demonstrated that defects are attracted to regions with maximal positive Gaussian curvature, K. On the contrary, anti-defects are attracted to membrane regions exhibiting minimal negative values of K. We show on membrane structures exhibiting spherical topology that the coexistence of regions with K > 0 and K < 0 might trigger formation of defect–anti-defect pairs for strong enough local membrane curvatures. Critical conditions for triggering pairs are determined in several demonstrative cases. Then the additionally appeared anti-defects are assembled at the membrane neck, where K < 0. Consequent strong local fluctuations of membrane constituent anisotropic molecules might trigger membrane fission neck rupture, enabling a membrane fission process and the release of membrane daughter microvesicles (ie, vesiculation).
Ključne besede: structural transitions, topological defects, membrane microvesicles, membrane curvature, membrane fission, vesiculation
Objavljeno: 03.08.2017; Ogledov: 49; Prenosov: 2
.pdf Celotno besedilo (4,92 MB)

Towards contemporary neuroethics
Niko Gorjup, Rado Gorjup, 2014, izvirni znanstveni članek

Opis: The main message we are trying to get across throughout the article is that the placebo is not an inert entity but instead it has a potential of subjective interpretation, a healing potential of its own, over and above that of any healing potential of the medication per se. Such healing potential is greatly dependent on how strong the interpretation value in being healed is that is created by the doctor. In this regard, we are also arguing that there are myriads possibilities at work that can influence how strong this interpretation value can become. The crucial role of contemporary medicine should be to expand the use of these interpretation effects even more and use them to help reduce any negative mental states that could continue to suppress the immune system after the initial healing. In other words, medicine should use the power of interpretation effect not only to re-arouse the immune system temporarily but permanently. In order to achieve a complete process of permanent healing it is necessary to take advantage of making full use of the powerful interpretation value through psychosocial context. It is possible to do that beyond the usual "sugar pill" through evidence based approach - a science of compassionate care! By introducing the new operational placebo definitions, we clearly show that the human mind (unconscious and conscious) is an inevitable substance involved in the Healing Process. The terms "placebo", "placebo effect", and "placebo response" are re-defined into the new working definitions. We explain how there is no more distinction (duality) such as body / mind, specific / nonspecific or health / disease, which offers new insights for future directions in contemporary Neuroethics.
Ključne besede: placebo, bioelectromagnetics, evidence-based medicine, compassionate care, neuroethics
Objavljeno: 03.08.2017; Ogledov: 40; Prenosov: 2
.pdf Celotno besedilo (183,83 KB)

Symmetry breaking and structure of a mixture of nematic liquid crystals and anisotropic nanoparticles
Marjan Krašna, Matej Cvetko, Milan Ambrožič, 2010, izvirni znanstveni članek

Opis: Orientational ordering of a homogeneous mixture of uniaxial liquid crystalline(LC) molecules and magnetic nanoparticles (NPs) is studied using the Lebwohl-Lasher lattice model. We consider cases where NPs tend to be oriented perpendicularly to LC molecules due to elastic forces. We study domain-type configurations of ensembles, which are quenched from the isotropic phase. We show that for large enough concentrations of NPs the long range uniaxial nematic ordering is replaced by short range order exhibiting strong biaxiality. This suggests that the impact of NPs on orientational ordering of LCs for appropriate concentrations of NPs is reminiscent to the influence of quenched random fields which locally enforce a biaxial ordering.
Ključne besede: liquid crystals, nanoparticles, disorder, orientational order, quenched disorder, symmetry breaking
Objavljeno: 03.08.2017; Ogledov: 57; Prenosov: 2
.pdf Celotno besedilo (447,84 KB)

Inheritance patterns in citation networks reveal scientific memes
Tobias Kuhn, Matjaž Perc, Dirk Helbing, 2014, izvirni znanstveni članek

Opis: Memes are the cultural equivalent of genes that spread across human culture by means of imitation. What makes a meme and what distinguishes it from other forms of information, however, is still poorly understood. Our analysis of memes in the scientific literature reveals that they are governed by a surprisingly simple relationship between frequency of occurrence and the degree to which they propagate along the citation graph. We propose a simple formalization of this pattern and validate it with data from close to 50 million publication records from the Web of Science, PubMed Central, and the American Physical Society. Evaluations relying on human annotators, citation network randomizations, and comparisons with several alternative approaches confirm that our formula is accurate and effective, without a dependence on linguistic or ontological knowledge and without the application of arbitrary thresholds or filters.
Ključne besede: memes, inheritance, genes, network science, complex systems
Objavljeno: 03.08.2017; Ogledov: 41; Prenosov: 2
.pdf Celotno besedilo (2,85 MB)

Correlation of positive and negative reciprocity fails to confer an evolutionary advantage: phase transitions to elementary strategies
Attila Szolnoki, Matjaž Perc, 2013, izvirni znanstveni članek

Opis: Economic experiments reveal that humans value cooperation and fairness. Punishing unfair behavioris therefore common, and according to the theory of strong reciprocity, it is also directly related to rewarding cooperative behavior. However, empirical data fail to confirm that positive and negative reciprocity are correlated. Inspired by this disagreement, we determine whether the combined application of reward and punishment is evolutionarily advantageous. We study a spatial public goods game, where in addition to the three elementary strategies of defection, rewarding, and punishment, a fourth strategy that combines the latter two competes for space. We find rich dynamical behavior that gives rise to intricate phase diagrams where continuous and discontinuous phase transitions occur in succession. Indirect territorial competition, spontaneous emergence of cyclic dominance, as well as divergent fluctuations of oscillations that terminate in an absorbing phase are observed. Yet, despite the high complexity of solutions, the combined strategy can survive only in very narrow and unrealistic parameter regions. Elementary strategies, either in pure or mixed phases, are much more common and likely to prevail. Our results highlight the importance of patterns and structure in human cooperation, which should be considered in future experiments.
Ključne besede: public goods, punishment, reward, evolutionary games, collective phenomena, phase transitions, physics of social systems
Objavljeno: 03.08.2017; Ogledov: 38; Prenosov: 3
.pdf Celotno besedilo (667,46 KB)

Comparison of cultivable acetic acid bacterial microbiota in organic and conventional apple cider vinegar
Aleksandra Mori Štornik, Barbara Skok, Janja Trček, 2016, izvirni znanstveni članek

Opis: Organic apple cider vinegar is produced from apples that go through very restricted treatment in orchard. During the first stage of the process, the sugars from apples are fermented by yeasts to cider. The produced ethanol is used as a substrate by acetic acid bacteria in a second separated bioprocess. In both, the organic and conventional apple cider vinegars the ethanol oxidation to acetic acid is initiated by native microbiota that survived alcohol fermentation. We compared the cultivable acetic acid bacterial microbiota in the production of organic and conventional apple cider vinegars from a smoothly running oxidation cycle of a submerged industrial process. In this way we isolated and characterized 96 bacteria from organic and 72 bacteria from conventional apple cider vinegar. Using the restriction analysis of the PCR-amplified 16S-23S rRNA gene ITS regions, we identified four different HaeIII and five different HpaII restriction profiles for bacterial isolates from organic apple cider vinegar. Each type of restriction profile was further analyzed by sequence analysis of the 16S-23S rRNA gene ITS regions, resulting in identification of the following species: Acetobacter pasteurianus (71.90 %), Acetobacter ghanensis (12.50 %), Komagataeibacter oboediens (9.35 %) and Komagataeibacter saccharivorans (6.25 %). Using the same analytical approach in conventional apple cider vinegar, we identified only two different HaeIII and two different HpaII restriction profiles of the 16S‒23S rRNA gene ITS regions, which belong to the species Acetobacter pasteurianus (66.70 %) and Komagataeibacter oboediens (33.30 %). Yeasts that are able to resist 30 g/L of acetic acid were isolated from the acetic acid production phase and further identified by sequence analysis of the ITS1-5.8S rDNA‒ITS2 region as Candida ethanolica, Pichia membranifaciens and Saccharomycodes ludwigii. This study has shown for the first time that the bacterial microbiota for the industrial production of organic apple cider vinegar is clearly more heterogeneous than the bacterial microbiota for the industrial production of conventional apple cider vinegar. Further chemical analysis should reveal if a difference in microbiota composition influences the quality of different types of apple cider vinegar.
Ključne besede: microbiology, acetic acid bacteria, apple cider vinegar
Objavljeno: 24.07.2017; Ogledov: 60; Prenosov: 4
.pdf Celotno besedilo (289,47 KB)

16S rRNA in situ hybridization followed by flow cytometry for rapid identification of acetic acid bacteria involved in submerged industrial vinegar production
Janja Trček, Luka Lipoglavšek, Gorazd Avguštin, 2016, izvirni znanstveni članek

Opis: Acetic acid bacteria are involved in many biotechnological processes such as vitamin C, gluconic acid, miglitol or acetic acid production, and others. For a technologist trying to control the industrial process, the ability to follow the microbiological development of the process is thus of importance. During the past few years hybridization in a combination with flow cytometry has oft en been used for this purpose. Since vinegar is a liquid, it is an ideal matrix for flow cytometry analysis. In this work we have constructed a specific probe for highly acetic acid-resistant species of the acetic acid bacteria and a protocol for in situ hybridization, which in combination with flow cytometry enables direct monitoring of bacteria producing vinegar with >10 % of acetic acid. The approach was successfully applied for monitoring microbiota during industrial vinegar production.
Ključne besede: microbiology, acetic acid bacteria, flow cytometry
Objavljeno: 24.07.2017; Ogledov: 63; Prenosov: 3
.pdf Celotno besedilo (500,81 KB)

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