Investigating associations of saproxylic beetles with forest structure through the analysis of species composition and feeding guilds
KOZEL, Petr
2024 - anglický The thesis contains studies focusing on various forest biotopes of Central Europe and saproxylic beetles as a model group for forest ecology research. In the review, current knowledge about the threats for forest biota, mainly saproxylic beetles are discussed in the context of species composition and trait-based approach. Various stages of succession in the patches of disturbed forests, their connectivity, the introduction non-native tree species, and the assessment of feeding guilds using stable isotopes are studied in the relation to saproxylic beetles in separate chapters. Klíčová slova: connectivity; forest ecology; non-native tree species; trait-based approach; saproxylic beetles; species composition; stable isotopes; succession Plné texty jsou dostupné v digitálním repozitáři JČU. Investigating associations of saproxylic beetles with forest structure through the analysis of species composition and feeding guilds

The thesis contains studies focusing on various forest biotopes of Central Europe and saproxylic beetles as a model group for forest ecology research. In the review, current knowledge about the ...

KOZEL, Petr
Jihočeská univerzita v Českých Budějovicích, 2024

Waste as a source of business opportunities for circular economy and bioeconomy
MAROUŠKOVÁ, Anna
2024 - anglický This dissertation thesis underlines the promising potential of biowaste processing using Black Soldier Fly (BSF) larvae with the subsequent production of value-added products such as feed components, fertilizers, cosmetics, etc. The concept is gaining global popularity, although legislative challenges initially hindered EU companies, resulting in delays in the placement of BSF products on the market. Nevertheless, EU enterprises, leveraging the time afforded by evolving legislation, emerged with cutting-edge technologies, positioning them to produce high-quality protein for animal feed and other value-added products. The study reveals a significant correlation between business development and scientific achievements in the field of BSF rearing in the EU and EFTA Member states. Another finding of this study was that countries with established Bioeconomy strategies at the national level show higher numbers of publications and established companies in the field of BSF rearing compared to those with Bioeconomy strategies under development or other bioeconomy-related policies. However, the biggest finding of this study is the results of the BSF meal, soybean meal and fish meal competitiveness analysis for the first time conducted in the Czech Republic. The comprehensive analysis showed that BSF meal has the potential to compete with products like soybean meal and fish meal despite its current market price is still a major drawback. The main benefits of the BSF meal are well-balanced nutritional properties and demonstrated positive ecological impact. It was also discovered that under the current conditions, the key bottlenecks are insufficient BSF products supply and the overly strict EU legislation which causes challenges in the price competitiveness. However, based on the review accompanied by the competitiveness analysis results and taking into account political trends, it can be concluded that industrial insect rearing represents a significant commercial potential. This dissertation thesis underlines the promising potential of biowaste processing using Black Soldier Fly (BSF) larvae with the subsequent production of value-added products such as feed components, fertilizers, cosmetics, etc. The concept is gaining global popularity, although legislative challenges initially hindered EU companies, resulting in delays in the placement of BSF products on the market. Nevertheless, EU enterprises, leveraging the time afforded by evolving legislation, emerged with cutting-edge technologies, positioning them to produce high-quality protein for animal feed and other value-added products. The study reveals a significant correlation between business development and scientific achievements in the field of BSF rearing in the EU and EFTA Member states. Another finding of this study was that countries with established Bioeconomy strategies at the national level show higher numbers of publications and established companies in the field of BSF rearing compared to those with Bioeconomy strategies under development or other bioeconomy-related policies. However, the biggest finding of this study is the results of the BSF meal, soybean meal and fish meal competitiveness analysis for the first time conducted in the Czech Republic. The comprehensive analysis showed that BSF meal has the potential to compete with products like soybean meal and fish meal despite its current market price is still a major drawback. The main benefits of the BSF meal are well-balanced nutritional properties and demonstrated positive ecological impact. It was also discovered that under the current conditions, the key bottlenecks are insufficient BSF products supply and the overly strict EU legislation which causes challenges in the price competitiveness. However, based on the review accompanied by the competitiveness analysis results and taking into account political trends, it can be concluded that industrial insect rearing represents a significant commercial potential. Klíčová slova: bioeconomy; circular economy; competitiveness; feed; insect protein Plné texty jsou dostupné v digitálním repozitáři JČU. Waste as a source of business opportunities for circular economy and bioeconomy

This dissertation thesis underlines the promising potential of biowaste processing using Black Soldier Fly (BSF) larvae with the subsequent production of value-added products such as feed components, ...

MAROUŠKOVÁ, Anna
Jihočeská univerzita v Českých Budějovicích, 2024

Anthropogenic impact on early-life stages of rheophilic fish
BARTOŇ, Daniel
2024 - anglický This study focuses on the problems faced by the early-life stages of fish living in a river influenced by reservoirs and suggests possible solutions to enhance recruitment. The model fish for the study is the asp (Leuciscus aspius), known for its significant and protected population in the Želivka Reservoir, from where it migrates for reproduction to the tributary of Želivka River. The asp migrates upstream in spring to spawn in shallow, fast-flowing waters. At a research site, the adult population of asp is monitored using passive telemetry. Fish are caught, tagged, and released back into the reservoir. The asp population faces threats due to hydropeaking and river fragmentation. Hydropeaking causes egg detachment from the pebbles and their sedimentation in the reservoir. The study suggests that water should not exceed a velocity of 0.7 m×s-1 at the spawning ground. Periodically increasing discharge also shifts spawning fish outside their preferred spawning site, causing disruption of spawning and potentially lowering recruitment. A flowdeflector was built to protect newly spawned eggs from hydropeaking. However, there are additional threats to the asp recruitment process such as egg consumption by non-indigenous fish like common bream (Abramis brama). Water flow conditions are crucial for the conservation of rheophilic fish, as these fish, aside from habitat loss and modification, also face newly interacting generalist fish species moving from lentic to lotic sections of the system. Fish communities can be affected by reservoir construction far upstream, and these anthropogenic habitat alterations have severe negative impacts on threatened rheophilic fish recruitment. This study focuses on the problems faced by the early-life stages of fish living in a river influenced by reservoirs and suggests possible solutions to enhance recruitment. The model fish for the study is the asp (Leuciscus aspius), known for its significant and protected population in the Želivka Reservoir, from where it migrates for reproduction to the tributary of Želivka River. The asp migrates upstream in spring to spawn in shallow, fast-flowing waters. At a research site, the adult population of asp is monitored using passive telemetry. Fish are caught, tagged, and released back into the reservoir. The asp population faces threats due to hydropeaking and river fragmentation. Hydropeaking causes egg detachment from the pebbles and their sedimentation in the reservoir. The study suggests that water should not exceed a velocity of 0.7 m×s-1 at the spawning ground. Periodically increasing discharge also shifts spawning fish outside their preferred spawning site, causing disruption of spawning and potentially lowering recruitment. A flowdeflector was built to protect newly spawned eggs from hydropeaking. However, there are additional threats to the asp recruitment process such as egg consumption by non-indigenous fish like common bream (Abramis brama). Water flow conditions are crucial for the conservation of rheophilic fish, as these fish, aside from habitat loss and modification, also face newly interacting generalist fish species moving from lentic to lotic sections of the system. Fish communities can be affected by reservoir construction far upstream, and these anthropogenic habitat alterations have severe negative impacts on threatened rheophilic fish recruitment. Plné texty jsou dostupné v digitálním repozitáři JČU. Anthropogenic impact on early-life stages of rheophilic fish

This study focuses on the problems faced by the early-life stages of fish living in a river influenced by reservoirs and suggests possible solutions to enhance recruitment. The model fish for the ...

BARTOŇ, Daniel
Jihočeská univerzita v Českých Budějovicích, 2024

A novel structurally characterized haloacid dehalogenase superfamily phosphatase from Thermococcus thioreducens with diverse substrate specificity
HAVLÍČKOVÁ, Petra
2024 - anglický This RNDr. thesis is focused on complex studies of a haloacid dehalogenase superfamily phosphatase member with an unknown substrate specificity, isolated from a hyperthermofilic archeon Thermococcus thioreducens. The HAD phosphatase, internally named as Tt82, was isolated, expressed and purified using standard techniques and the crystal structure was solved by X-ray crystallography method. The refined crystal structure displayed characteristic HAD superfamily elements, such as the HAD canonical fold with the HAD signature motifs in the active site. Further, possible substrates for the enzyme were proposed and examined by computational docking in the active site of the HAD phosphatase. The results of the docking studies served as a basis for an experimental measurement of Tt82 enzymatic activity against selected substrates at two different temperatures. HAD phosphatase Tt82 is a promising target for the biotechnological field, mainly for its wide substrate specificity and higher temperature optima. Plné texty jsou dostupné v digitálním repozitáři JČU. A novel structurally characterized haloacid dehalogenase superfamily phosphatase from Thermococcus thioreducens with diverse substrate specificity

This RNDr. thesis is focused on complex studies of a haloacid dehalogenase superfamily phosphatase member with an unknown substrate specificity, isolated from a hyperthermofilic archeon Thermococcus ...

HAVLÍČKOVÁ, Petra
Jihočeská univerzita v Českých Budějovicích, 2024

Functional Ultrastructure of Hymenopteran Stingers: Devastating Spear or Delicate Syringe
ČERNÝ, Jan
2024 - anglický In this study, we tested the hypothesis that a micro-serrated edge on the honey bee Apis mellifera stinger tip serves as a tool for more intensive crushing of cell membranes in the victim's tissues. This could have mechanical consequences as well as initiate metabolic pathways linked to cell membrane breakdown (e.g., production of biogenic amines). Accordingly, we found that hymenopteran species that use their stingers as an offensive or defensive weapon to do as much damage to the victim's body as possible had this cuticular microstructure. In parasitic hymenopterans, on the other hand, this structure was missing, as stingers are solely used to delicately transport venom to the victim's body in order to do little mechanical harm. We also demonstrated that the stinger lancets of the honey bee A. mellifera are living organs with sensilla innervated by sensory neurons and containing other essential tissues, rather than mere cuticular structures. Klíčová slova: bee; Hymenoptera; nerve; SEM; sensilla; stinger microstructure; TEM; ultrastructure Plné texty jsou dostupné v digitálním repozitáři JČU. Functional Ultrastructure of Hymenopteran Stingers: Devastating Spear or Delicate Syringe

In this study, we tested the hypothesis that a micro-serrated edge on the honey bee Apis mellifera stinger tip serves as a tool for more intensive crushing of cell membranes in the victim's tissues. ...

ČERNÝ, Jan
Jihočeská univerzita v Českých Budějovicích, 2024

Functional characterization of the insulin signaling pathway in the hard tick Ixodes ricinus
KOZELKOVÁ, Tereza
2024 - anglický In this thesis, the molecular and functional characterization of the insulin receptor signaling pathway (ISP) in hard tick Ixodes ricinus was characterized. As obligatory blood-feeding ectoparasites, ticks play a crucial role in the transmission of various pathogens, including bacteria, viruses, and protozoa, which has a significant impact on human and animal health. The parasite is strictly bonded with its host through a unidirectional transmission of nutrition for its survival, development, and reproduction. The ISP, a highly conserved system, regulates numerous physiological and anabolic processes to nutritional availability. This study aims to investigate the functionality of key components of the ISP pathway identified in the midgut transcriptome, namely the insulin receptor (IrInR), the protein kinase B called AKT (IrAKT), and the target of rapamycin (IrTOR). To achieve this goal, the expression profiles of these components in tick tissues during feeding and after detachment were investigated using qRT-PCR. Additionally, RNAi silencing of individual components was performed, and the phenotype of the ticks was observed. To further clarify the effects of ISP, immunization of rabbits with recombinant IrInR protein and tick infestation were investigated. Plné texty jsou dostupné v digitálním repozitáři JČU. Functional characterization of the insulin signaling pathway in the hard tick Ixodes ricinus

In this thesis, the molecular and functional characterization of the insulin receptor signaling pathway (ISP) in hard tick Ixodes ricinus was characterized. As obligatory blood-feeding ...

KOZELKOVÁ, Tereza
Jihočeská univerzita v Českých Budějovicích, 2024

Oligomerization state and pigment contents of algal light-harvesting proteins
MALINOVÁ, Kateřina
2023 - anglický Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus minutus) were studied. LHCs were extracted and purified using sucrose gradient ultracentrifugation and ion-exchange chromatography. Oligomerization states of LHCs were assessed using two independent methods - CN-PAGE and size-exclusion chromatography. Effects of the purification on LHC pigment composition was assessed using HPLC. Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus minutus) were studied. LHCs were extracted and purified using sucrose gradient ultracentrifugation and ion-exchange chromatography. Oligomerization states of LHCs were assessed using two independent methods - CN-PAGE and size-exclusion chromatography. Effects of the purification on LHC pigment composition was assessed using HPLC. Klíčová slova: pigments; LHC; HPLC; alga; SEC; IEC Plné texty jsou dostupné v digitálním repozitáři JČU. Oligomerization state and pigment contents of algal light-harvesting proteins

Light-harvesting antennas (LHCs) from four microalgae species (diatom Phaeodactylum tricornutum, haptophyte Emiliania huxleyi, and two eustigmatophytes Nannochloropsis oceanica and Trachydiscus ...

MALINOVÁ, Kateřina
Jihočeská univerzita v Českých Budějovicích, 2023

Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva
ŠAFFA, Gabriel
2023 - anglický This thesis investigates the adaptive significance of seemingly maladaptive human behaviors or cultural norms that are often viewed as responses to intra- and inter-sexual conflict. It combines behavioral ecological approach with phylogenetic comparative methods to study evolutionary origins and maintenance of these practices, using samples of ethnographically documented human societies. The thesis is divided into three sections. The first section is the introduction to evolutionary sciences of human behavior, including an overview of the theoretical perspectives and a critical evaluation of the methodological approaches to macro-evolutionary studies of human behavior and culture. The second section consists of three chapters - two published research papers and a manuscript that is currently under review. The first paper investigates female and male genital mutilation/cutting practices, their evolutionary history, and socio-ecological correlates; the second paper investigates restrictions on female premarital sex and evaluates the three hypotheses explaining them - male, female, and parental control hypothesis; the third paper investigates the causes of socially imposed monogamy and evaluates the competing hypotheses explaining its prevalence in stratified, agricultural societies. The last section summarizes the results of the three studies and concludes with perspectives of future research. Klíčová slova: adaptation; causal inference; cultural evolution; human behavioral ecology; phylogenetics; regression Plné texty jsou dostupné v digitálním repozitáři JČU. Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva

This thesis investigates the adaptive significance of seemingly maladaptive human behaviors or cultural norms that are often viewed as responses to intra- and inter-sexual conflict. It combines ...

ŠAFFA, Gabriel
Jihočeská univerzita v Českých Budějovicích, 2023

Environmental and socio-cultural determinants of language skills and ethnobiological knowledge in Papua New Guinea and Cameroon
KIK, Alfred
2023 - anglický Plné texty jsou dostupné v digitálním repozitáři JČU. Environmental and socio-cultural determinants of language skills and ethnobiological knowledge in Papua New Guinea and Cameroon

KIK, Alfred
Jihočeská univerzita v Českých Budějovicích, 2023

Functional analysis of cryoprotectant system in Chymomyza costata
GRGAC, Robert
2023 - anglický In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying extreme freeze tolerance in the larvae of the drosophilid fly, Chymomyza costata. Metabolomics unveiled the complex composition of the seasonally accumulated larval innate mixture of putative cryoprotectants. This mixture was predominantly composed of proline and trehalose, supplemented by minor components (glutamine, asparagine, betaine, sarcosine, glycerophospho-choline, and ethanolamine). We identified food ingestion as a significant source for the direct assimilation of amino compounds, while glycogen and phospholipids served as the primary internal sources for the biosynthesis of other cryoprotectants. The utilization of MALDI-MSI to observe cryoprotectants revealed distinct behaviors of proline and trehalose during ecologically relevant, gradual inoculative extracellular freezing of larvae. Trehalose exhibited accumulation in partially dehydrated hemolymph, inducing a transition to the amorphous glass phase. On the other hand, proline migrated to the boundary between extracellular ice and dehydrated hemolymph and tissues, forming a layer of dense viscoelastic liquid. Finally, through a combination of in vivo and in vitro assays, we found that cell membranes are likely targets of freezing injury, while their integrity is sustained by accumulated small cryoprotective molecules and proteins in cold-acclimated C. costata larvae. Contrary to our expectations, our assays did not provide support for the hypothesis that proteins (soluble enzymes) require in vivo stabilization through the accumulation of cryoprotectants. In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying extreme freeze tolerance in the larvae of the drosophilid fly, Chymomyza costata. Metabolomics unveiled the complex composition of the seasonally accumulated larval innate mixture of putative cryoprotectants. This mixture was predominantly composed of proline and trehalose, supplemented by minor components (glutamine, asparagine, betaine, sarcosine, glycerophospho-choline, and ethanolamine). We identified food ingestion as a significant source for the direct assimilation of amino compounds, while glycogen and phospholipids served as the primary internal sources for the biosynthesis of other cryoprotectants. The utilization of MALDI-MSI to observe cryoprotectants revealed distinct behaviors of proline and trehalose during ecologically relevant, gradual inoculative extracellular freezing of larvae. Trehalose exhibited accumulation in partially dehydrated hemolymph, inducing a transition to the amorphous glass phase. On the other hand, proline migrated to the boundary between extracellular ice and dehydrated hemolymph and tissues, forming a layer of dense viscoelastic liquid. Finally, through a combination of in vivo and in vitro assays, we found that cell membranes are likely targets of freezing injury, while their integrity is sustained by accumulated small cryoprotective molecules and proteins in cold-acclimated C. costata larvae. Contrary to our expectations, our assays did not provide support for the hypothesis that proteins (soluble enzymes) require in vivo stabilization through the accumulation of cryoprotectants. Plné texty jsou dostupné v digitálním repozitáři JČU. Functional analysis of cryoprotectant system in Chymomyza costata

In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying ...

GRGAC, Robert
Jihočeská univerzita v Českých Budějovicích, 2023