SELEKTIVNOST PLIJENA U SOMA (Silurus glanis) I AFRIČKOG SOMA (Clarias gariepinus)

The experiments aimed at prey selectivity in two Siluriformes predators. African catfish, Clarias gariepinus, and wels, Silurus glanis, were performed under laboratory conditions. Prey fish (12-22% TL of predator) were submitted to one.year.old African catfish (~220 g) and wels (~150 g) originating from intensive culture, ie with no previous experience with live fish food. In African catfish, negative selectivity (avoidance) was shown for Nile tilapia (Oreochromis niloticus) and topmouth gudgeon (Pseudorasbora parva) whilst rudd(Scardinius erythrophthalmus) and sunbleak (Leucaspius delineatus) were preferred (positive selectivity). The intensity and efficiency of African catfish predation were quite low because its feeding strategy is based rather on prey searching than hunting. Prey fish, wounded and/or dead from its clumsy attacks, were sonsumed preferably overnight. Not one successful attack of African catfish on healthy prey fish was registered. The SGR and FCR of clarias fed live fish were 0.39%. day-1 and 4.73 respectively. In wels, strong negative selectivity (avoidance) was proved for roach (Rutilus rutilus) and topmouth gungeon, and lower avoidance for Prussian carp (Carassius auratus gibelio) and chub (Leuciscus cephalus). Asp (Aspius aspius) were found to be low preferred but high preference was shown for sunbleak, rudd and bitterling (Rhodeus sericeus). Both catfishes preferred smaller prey fish during the 10.day experimental period whilst those which remained non-consumed belonged to the mean or above-mean size categories.Istraživanja su bila usmjerena na selektivnost plijena u dvije vrste grabežljivaca siluriformes - afričkog soma (Clarius gariepinus) i soma (Silurus glanis). Istraživanja su provedena u laboratorijskim uvjetima. Riba plijen (12-22% TL grabežljivaca) poslužila je jednogodišnjem afričkom somu (~220 g) i somu (~150 g) porijeklom iz intenzivnog uzgoja bez prethodnog iskustva u prehrani živim ribama. Afrički je som pokazao negativnu seletivnost (izbjegavanje) prema nilskoj tilapiji (Oreochromis niloticus) i amurskom čebačoku (Pseudorasbora parva), a crvenperka (Scardinius erythrophthalmus) i bjelica (Leucaspius delineatus) bile su preferirane (pozitivna selektivnost). Intenzitet i efikasnost proždrljivosti afričkog soma bila je posve niska, jer je njegova hranidbena strategija u osnovi zapravo na selektivnosti traženja, a ne lova. Plijen, ozlijeđen ili mrtav u tijeku neefikasnog lova, bio je bolje konzumiran za vrijeme noći. Ni jedan uspješan napad afričkog soma na zdravi plijen nije registriran. U soma je bila dokazana jaka negativna selektivnost (uklanjanje) za bodorku (Rutilus rutilus) i amurski čebačok (Pseudorasbora parva), a slabije izbjegavanje za babušku (Carassius auratus gibelio) i klena (Leuciscus cephalus). Bolen (Aspius aspius) nisko je preferiran, dok je visoka preferiranost pokazana za bjelicu (Leucaspius delineatus), crvenperku (Scardinius erythrophthalmus) i gavčicu (Rhodeus sericeus). Obje vrste soma preferirale su manji plijen za vrijeme desetodnevnog eksperimentalnog razdoblja, dok su oni koji su ostali nekonzumirani pripadali kategoriji srednjih ili većih riba

SELEKTIVNOST PLIJENA U SOMA (Silurus glanis) I AFRIČKOG SOMA (Clarias gariepinus)

The experiments aimed at prey selectivity in two Siluriformes predators. African catfish, Clarias gariepinus, and wels, Silurus glanis, were performed under laboratory conditions. Prey fish (12-22% TL of predator) were submitted to one.year.old African catfish (~220 g) and wels (~150 g) originating from intensive culture, ie with no previous experience with live fish food. In African catfish, negative selectivity (avoidance) was shown for Nile tilapia (Oreochromis niloticus) and topmouth gudgeon (Pseudorasbora parva) whilst rudd(Scardinius erythrophthalmus) and sunbleak (Leucaspius delineatus) were preferred (positive selectivity). The intensity and efficiency of African catfish predation were quite low because its feeding strategy is based rather on prey searching than hunting. Prey fish, wounded and/or dead from its clumsy attacks, were sonsumed preferably overnight. Not one successful attack of African catfish on healthy prey fish was registered. The SGR and FCR of clarias fed live fish were 0.39%. day-1 and 4.73 respectively. In wels, strong negative selectivity (avoidance) was proved for roach (Rutilus rutilus) and topmouth gungeon, and lower avoidance for Prussian carp (Carassius auratus gibelio) and chub (Leuciscus cephalus). Asp (Aspius aspius) were found to be low preferred but high preference was shown for sunbleak, rudd and bitterling (Rhodeus sericeus). Both catfishes preferred smaller prey fish during the 10.day experimental period whilst those which remained non-consumed belonged to the mean or above-mean size categories.Istraživanja su bila usmjerena na selektivnost plijena u dvije vrste grabežljivaca siluriformes - afričkog soma (Clarius gariepinus) i soma (Silurus glanis). Istraživanja su provedena u laboratorijskim uvjetima. Riba plijen (12-22% TL grabežljivaca) poslužila je jednogodišnjem afričkom somu (~220 g) i somu (~150 g) porijeklom iz intenzivnog uzgoja bez prethodnog iskustva u prehrani živim ribama. Afrički je som pokazao negativnu seletivnost (izbjegavanje) prema nilskoj tilapiji (Oreochromis niloticus) i amurskom čebačoku (Pseudorasbora parva), a crvenperka (Scardinius erythrophthalmus) i bjelica (Leucaspius delineatus) bile su preferirane (pozitivna selektivnost). Intenzitet i efikasnost proždrljivosti afričkog soma bila je posve niska, jer je njegova hranidbena strategija u osnovi zapravo na selektivnosti traženja, a ne lova. Plijen, ozlijeđen ili mrtav u tijeku neefikasnog lova, bio je bolje konzumiran za vrijeme noći. Ni jedan uspješan napad afričkog soma na zdravi plijen nije registriran. U soma je bila dokazana jaka negativna selektivnost (uklanjanje) za bodorku (Rutilus rutilus) i amurski čebačok (Pseudorasbora parva), a slabije izbjegavanje za babušku (Carassius auratus gibelio) i klena (Leuciscus cephalus). Bolen (Aspius aspius) nisko je preferiran, dok je visoka preferiranost pokazana za bjelicu (Leucaspius delineatus), crvenperku (Scardinius erythrophthalmus) i gavčicu (Rhodeus sericeus). Obje vrste soma preferirale su manji plijen za vrijeme desetodnevnog eksperimentalnog razdoblja, dok su oni koji su ostali nekonzumirani pripadali kategoriji srednjih ili većih riba

SOME HEMATOLOGICAL VALUES OF TWO-YEAR OLD CARP (Cyprinus carpio L.)

Istraženo je djelovanje različitih tehnologija (I - bez gnojidbe, prihranjivanje riba žitaricama, II - gnojidba, prihranjivanje riba žitaricama i III - bez gnojidbe, prihranjivanje riba briketima s 20% životinjskih proteina) u uzgoju šarana u polikulturi s bijelim i sivim glavašem i bijelim amurom na neke hematološke pokazatelje (hematokrit, koncentracija hemoglobina, srednja koncentracija boje, ukupni proteini i ukupni lipidi). Gustoća je nasada bila 3.250 ind˙ha-1, a od toga šaran s 2.500 ind˙ha-1 (772). Prosječna vrijednost hemoglobina u krvnom serumu šarana bila je u kontrolnoj varijanti I 111,80±18,38 gr1, u varijanti II s gnojidbom mineralnim gnojivom NPK (17: 8: 9) i prihranjivanjem žitaricama 121,60±15,86, a u varijanti III bez gnojidbe i uz prihranjivanje briketima s 20% proteina 122,00±15,61 g˙l-1. Vrijednost je hematokrita iznosila pripadajuće 0,25±O,03, O,30±0,03 i O,28±0,00 L˙L-1, te srednja koncentracija boje 0,23±0,01, 0,23±O,01 i O,25±0,01 L˙L-1. Prosječna količina ukupnih proteina u krvnom serumu šarana iznosila je 27,OO±O,32 (varijanta I), 32,00±0,52 (varijanta II) i 34,00±1,02 (varijanta III). Prosječna vrijednost ukupnih lipida u krvnom serumu šarana bila je 1O,10±O,29 gr1 (varijanta I), 11,20±1,60 g˙l-1 (varijanta II) i l1,20±1,60 g˙l-1 (varijanta III). Statistički opravdane razlike utvrđene su samo u količini ukupnih proteina u serumu šarana (P>0,05), i to u korist varijante III u kojoj je šaran prihranjivan bjelančevinama životinjskog porijekla.An investigation was carried out in three variants of experimental fish ponds in which different technologies were applied (l - without fertilizing, feeding of carp with cereals; II - fertilizing, feeding of carp with cereals; III - without fertilizing, feeding of carp with pellets containing 20% of protein). Carp was reared under conditions of policulture with total stock density 3250 ind. ha-1 (2500 ind•ha-1 carp 250 ind•ha-1 silver carp, 250 ind•ha-1 bighead and 250 ind•ha-1 grass carp. Average weights of fishes were from 29 to 77 g. The values of some hematological and biochemical indices of carp were estimated (hematocrit, hemoglobin, MCHC, total protein and total lipids). The mean value of concentration of hemoglobin was 111,80±18,38 gl-1 (variant I); 121,60±15,86 gl-1 (variant II) and 122,00±15,61 gl-1 (variant III). Hematocrit value was 0,25±0,03 L˙L-1 0,30±0,03 L˙L-1 0,28±0,02 L˙L-1, and MCHC 0,23±0,01 L˙L-1; 0,23±0,01 L˙L-1; 0,25±0,01 L˙L-1 resp. The concentration of total protein in blood plasma of carp was 27,00±0,32 g˙L-1 (variant 1), 32,00±0,52 g˙L-1 (variant II) and 34,00±1,02 g˙L-1 (variant III). The concentration oftotallipids was 10,1O±0,29 g˙L-1,11,20±1,60 g˙L-1 and 1l,20±1,60 g˙L-1 resp. The differences between means values of these indices found in carp of different variants were significant (P>0.05) only for values of total protein (table 3) in variant III where carp was fed with protein of animal origin

Sound and complete axiomatizations of coalgebraic language equivalence

Coalgebras provide a uniform framework to study dynamical systems, including several types of automata. In this paper, we make use of the coalgebraic view on systems to investigate, in a uniform way, under which conditions calculi that are sound and complete with respect to behavioral equivalence can be extended to a coarser coalgebraic language equivalence, which arises from a generalised powerset construction that determinises coalgebras. We show that soundness and completeness are established by proving that expressions modulo axioms of a calculus form the rational fixpoint of the given type functor. Our main result is that the rational fixpoint of the functor $FT$, where $T$ is a monad describing the branching of the systems (e.g. non-determinism, weights, probability etc.), has as a quotient the rational fixpoint of the "determinised" type functor $\bar F$, a lifting of $F$ to the category of $T$-algebras. We apply our framework to the concrete example of weighted automata, for which we present a new sound and complete calculus for weighted language equivalence. As a special case, we obtain non-deterministic automata, where we recover Rabinovich's sound and complete calculus for language equivalence.Comment: Corrected version of published journal articl

CHIRONOMUS PLUMOSUS LARVAE - A SUITABLE NUTRIENT FOR FRESHWATER FARMED FISH

Crude protein, fat, water, ash, dry matter and essential amino and fatty acids were analyzed from freshly collected Chironomus plumosus larvae in order to evaluate their suitability as a component for farmed fish diet. The analyses were performed in intact living organisms and in the dry matter. Essential amino acids were determined by LKB 4101 automatic analyzer, while fatty acids were determined by Chronopack CP 9000 chromatograph with flame ionization detector. Crude protein content was 7.6% and 55.7% in fresh larvae and dry matter, respectively, being a value adequate for growth needs of all freshwater fish sorts and categories. Most essential amino acids in fresh larvae and dry matter are present in quantities adequate for feeding majority of omnivorous and carnivorous freshwater fish species. Crude fat content was 1.3% and 9.7% in fresh larvae and dry matter, respectively, being energetically sufficient for all warm-water living fish. The crude fat contains 26.12% saturated, 30.42% monounsaturated and 34.03% polyunsaturated fatty acids (PUFA). Among the highly unsaturated fatty acids (HUFA), the most abundant is linolenic (7.21%), followed by eicosapentanoic (4.36%), docosahexaenoic (2.49%) and docosapentaenoic (1.16%) acid. The measured quantity of ω-3 and ω-6 fatty acids (essential for omnivorous fish), as well as ω-6 to ω-3 fatty acid ratio (0.81), completely meets nutritional requirements of carp and tench

Effects of Age and Loading Velocity on the Delamination Strength of the Human Aorta

Delamination strength is the mechanical property which plays a key role in the pathological process referred to as Arterial Dissection. This dissection, known especially for its occurrence in the thoracic aorta, is manifested by a separation of the layers of an artery wall, and may end with total rupture and internal haemorrhaging. Although its incidence is relatively rare, from 3 to 6 cases per 100 000 per year, it is a life-threating disease with a significant lethality [1-3]. The exact conditions under which the dissection is initiated, and as a crack propagates through the arterial wall, remain an open topic in computational as well as experimental mechanics. The aim of our study is to contribute to the deepening of our knowledge of Arterial Dissection, by collecting experimental data which is suitable for the purpose of showing how the delamination strength measured in the peeling experiments depends on age and anatomical location. In addition to the effects of age and location, our study also focuses on the effect of loading rate. The experimental branch of our research is complemented by a computational modelling of the delamination interface, in which we are looking for a numerical characterization of the material parameters describing discontinuity propagation. An XFEM model of the peeling experiment is built in Abaqus, which in our approach plays the role of the regression analysis, incorporating the cohesive zone (CZ) in order to model the delaminating arterial layers. The main objective is to obtain a detailed description of a set of constitutive parameters, which would be age- and location-specific. Our present data suggest that delamination strength strongly depends on age, and furthermore, the anatomical site also seems to be a significant factor. On the other hand, the loading velocity does not cause significant changes in results

Current Wildland Fire Patterns and Challenges in Europe: A Synthesis of National Perspectives

Changes in climate, land use, and land management impact the occurrence and severity of wildland fires in many parts of the world. This is particularly evident in Europe, where ongoing changes in land use have strongly modified fire patterns over the last decades. Although satellite data by the European Forest Fire Information System provide large-scale wildland fire statistics across European countries, there is still a crucial need to collect and summarize in-depth local analysis and understanding of the wildland fire condition and associated challenges across Europe. This article aims to provide a general overview of the current wildland fire patterns and challenges as perceived by national representatives, supplemented by national fire statistics (2009–2018) across Europe. For each of the 31 countries included, we present a perspective authored by scientists or practitioners from each respective country, representing a wide range of disciplines and cultural backgrounds. The authors were selected from members of the COST Action “Fire and the Earth System: Science & Society” funded by the European Commission with the aim to share knowledge and improve communication about wildland fire. Where relevant, a brief overview of key studies, particular wildland fire challenges a country is facing, and an overview of notable recent fire events are also presented. Key perceived challenges included (1) the lack of consistent and detailed records for wildland fire events, within and across countries, (2) an increase in wildland fires that pose a risk to properties and human life due to high population densities and sprawl into forested regions, and (3) the view that, irrespective of changes in management, climate change is likely to increase the frequency and impact of wildland fires in the coming decades. Addressing challenge (1) will not only be valuable in advancing national and pan-European wildland fire management strategies, but also in evaluating perceptions (2) and (3) against more robust quantitative evidence

Impact of water quality and physical habitat degradation upon fish biodiversity in small streams of the Czech Republic

The data obtained during the surveys of fish assemblages in Czech streams of the Danube and Elbe river basins were evaluated with respect to the relation between fish biodiversity and level of water (organic pollution) and/or physical habitat quality (longitudinal heterogeneity, substrate, riparian vegetation, canalisation). Fish asseblages showed the highest biodiversity in betamezosaprobity in both lowland and highland streams. Their response were more pronounced regarding water quality rather than physical habitat deterioration, i.e. fish biodiversity declined with decreasing water quality more considerably than with physical habitat degradation