Regenerace smyslových orgánů u raků
KOR, Golara
2024 - English Anteny jsou u raků důležitým smyslovým orgánem, které mají zásadní roli na jejich přežití, komunikaci a orientaci v prostředí. Jsou vybaveny smyslovými chloupky, které umožňují rakům detekovat různé podněty. Raci mají jedinečnou schopnost regenerovat své anteny. Hemocyty jsou specializované buňky raků a hrají klíčovou roli v jejich imunitním systému a podílejí se na procesu regenerace. Ke studiu morfologie a regenerace smyslových orgánů u raků jsme použili kryo-skenování a transmisní elektronové mikroskopy. V kapitole 2 byla kryo-skenovací elektronová mikroskopie použita k identifikaci potenciálních rozdílů v morfologii anten u šesti různých druhů raků, zahrnujících raka mramorovaného Procambarus virginalis, raka mexického Cambarellus patzcuarensis), raka červeného (Procambarus clarkii), raka signálního (Pacifastacus leniusculus), raka ničivého (Cherax destructor) a raka pruhovaného (Faxonius limosus). Zjistili jsme významné rozdíly mezi šesti druhy raků v poměru délky anteny, délky a šířky segmentu k délce krunýře a počtu segmentů. Zkoumání ultrastrukturálních rysů odhalilo rozdíly ve vzorcích distribuce smyslových chloupků podél anten a morfologii povrchu anten. Rozdílná morfologie anten mezi studovanými druhy pravděpodobně ukazuje na přizpůsobení se specifickým podmínkám jejich příslušných stanovišť. Výsledky dále ukázaly, že kombinace morfologických charakteristik anten nám může pomoci rozlišit různé studované druhy raků. V kapitole 3 bylo pomocí transmisní elektronové mikroskopie zkoumáno ultrastrukturální chování hemocytů během koagulace a fagocytózy v počátečních fázích poranění u raka mramorovaného. Během koagulačního procesu prodělaly hemocyty výrazné transformace v morfologii. Cytoplazmatická granula vykazovala změnu z elektronově hustých na elektronově prostupné formy s postupem koagulace. Bylo pozorováno, že transformované granule obsahují amorfní, pro eletrony prostupný materiál navzájem spojený a uvolňující svůj obsah do extracelulárního prostoru jako součást koagulačního procesu. Kromě toho bylo pozorováno, že obsah jádra také hraje roli během procesu koagulace. Navíc amputace nohy vedla k silné svalové degeneraci a fagocytující hemocyty začaly pohlcovat nekrotické tkáně. Kromě toho jsme pozorovali natrávené zbytky z fagocytovaných nekrotických tkání sloučených do granulí a dalších buněčných složek, čímž se zvýšila granularita hemocytů a změnila se jejich buněčná morfologie. Je však nutno poznamenat, že degranulace hemocytů během koagulace by mohla potenciálně snížit jejich granularitu. Vzhledem k tomu, že morfologické vlastnosti jsou pro klasifikaci hemocytů zcela zásadní, musí být tyto morfologické změny během koagulace a fagocytózy považovány za významné faktory. Degenerovaný materiál uložený uvnitř fagocytárních hemocytů může mít uplatnění v imunologických a regeneračních procesech. V kapitole 4 jsme použili transmisní elektronovou mikroskopii, abychom prozkoumali ultrastrukturální aspekty potenciálního zapojení imunitních buněk do regenerace nervů po amputaci anten raků. Zjištění ukázala, že během regenerace nervů byly přítomny všechny tři formy hemocytů. Nicméně granule v semigranulocytech a granulocytech přispěly především ke vzniku nových organel, jako jsou mitochondrie, Golgiho aparát a nervová vlákna v regenerovaných nervech račích anten. Odhalili jsme transformaci granulí hemocytů na různé organely během procesu regenerace nervů na ultrastrukturální úrovni. Závěrem lze říci, že tyto granule fungují jako kompaktní úložiště adaptabilních materiálů nesených imunitními buňkami, schopných transformace na různé organely během regenerace nervů v račích anten. The antennae are a crucial sensory organ in crayfish that plays vital roles in their survival, communication, and orientation within their environment. They are equipped with sensory hairs that enable crayfish to detect various stimuli. Crayfish possess the unique ability to regenerate their antennae. Hemocytes are specialized cells within crayfish and play a crucial role in their immune system and contribute to the process of regeneration. We applied cryo-scanning and Transmission electron microscopies to study sensory organ morphology and regeneration in crayfish. In Chapter 2, cryo-scanning electron microscopy was used to identify potential differences in antennal morphology in six different crayfish species including marbled crayfish Procambarus virginalis, Mexican dwarf crayfish Cambarellus patzcuarensis, red swamp crayfish Procambarus clarkii, signal crayfish Pacifastacus leniusculus, common yabby Cherax destructor, and spiny-cheek crayfish Faxonius limosus. We observed significant differences among the six crayfish species in the ratios of antenna length, segment length and width to carapace length, and the number of segments. Examination of ultrastructural features unveiled differences in the distribution patterns of sensory hairs along the antenna and the morphology of the antennal surface. The varying morphology of antennae among studied species possibly indicates an adaptation to the specific conditions of their respective habitats. Furthermore, the outcomes demonstrated that a combination of variations in both antennal morphological characteristics and biometric measurements could effectively help us to distinguish the different studied crayfish species. In Chapter 3, the ultrastructural behaviour of hemocytes during coagulation and phagocytosis in the initial phases of injury in marbled crayfish was explored using transmission electron microscopy. During the coagulation process, hemocytes experienced marked transformations in morphology. The cytoplasmic granules exhibited a change from electron-dense to electron-lucent forms with the progress of coagulation. The transformed granules containing amorphous, electron-lucent material were observed to combine and release their contents into the extracellular space as part of the coagulation process. Additionally, it was observed that the nucleus contents also play a role in the coagulation process. Furthermore, the amputation of the leg led to substantial muscle degeneration, and phagocytic hemocytes start to take up the necrotic tissues. Besides, we observed the digested remains from phagocytized necrotic tissues merged into granules and other cellular components, thereby enhancing the granularity of the hemocytes and altering their cellular morphology. However, it is essential to note that hemocyte degranulation during coagulation could potentially reduce their granularity. Since morphological features are critical for classifying hemocytes, these morphological changes during coagulation and phagocytosis must be considered significant factors. The degenerated material that stored inside phagocytic hemocytes may have application in immunological and regeneration processes. In Chapter 4, we employed transmission electron microscopy to explore the ultrastructural aspects of potential immune cell involvement in nerve regeneration within crayfish antennae post-amputation. The findings indicated that, during nerve regeneration, all three forms of hemocytes were present. However, the granules within semi-granulocytes and granulocytes mainly contributed to the generation of new organelles such as mitochondria, the Golgi apparatus, and nerve fibers in the regenerated nerves of crayfish antennae. We revealed the transformation of granules of hemocytes into diverse organelles during the process of nerve regeneration at the ultrastructural level. In conclusion, these granules function as compact repositories of adaptable materials carried by immune cells, capable of transformatio Keywords: Anteny; Elektronová mikroskopie; Hemocyt; Imunitní systém; Regenerace Available in the Digital Repository of University of South Bohemia. Regenerace smyslových orgánů u raků

Anteny jsou u raků důležitým smyslovým orgánem, které mají zásadní roli na jejich přežití, komunikaci a orientaci v prostředí. Jsou vybaveny smyslovými chloupky, které umožňují rakům detekovat různé ...

KOR, Golara
Jihočeská univerzita v Českých Budějovicích, 2024

The study of the phylogeny and taxonomy of selected genera of Erebidae (Lepidoptera; Noctuoidea) as a tool for understanding of origin of the Afrotropical moth fauna
IGNATEV, Nikolai
2024 - English In this thesis, I conducted the taxonomical and phylogenetical research of selected Afrotropical moth genera, especially an Old-World moth genus Amerila, Walker 1855. All the studied genera belong to the family Erebidae (Lepidoptera; Noctuoidea) and are well-presented in the state European entomological collections. In our research, we used mitochondrial, or mitochondrial and nuclear markers and different molecular analyses to resolve relationships within the studied genera (exclude Meganaclia, Aurivillius 1892). Comparative morphological analysis was used in all the studies. We aimed to update the classification of studied Lepidoptera genera, and to highlight the gaps in taxonomical study of Afrotropical moth fauna in general. Keywords: arctiinae; ancestral state reconstruction; integrative taxonomy; morphological characters Available in the Digital Repository of University of South Bohemia. The study of the phylogeny and taxonomy of selected genera of Erebidae (Lepidoptera; Noctuoidea) as a tool for understanding of origin of the Afrotropical moth fauna

In this thesis, I conducted the taxonomical and phylogenetical research of selected Afrotropical moth genera, especially an Old-World moth genus Amerila, Walker 1855. All the studied genera belong to ...

IGNATEV, Nikolai
Jihočeská univerzita v Českých Budějovicích, 2024

Investigating associations of saproxylic beetles with forest structure through the analysis of species composition and feeding guilds
KOZEL, Petr
2024 - English 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. Keywords: connectivity; forest ecology; non-native tree species; trait-based approach; saproxylic beetles; species composition; stable isotopes; succession Available in the Digital Repository of University of South Bohemia. 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

Anthropogenic impact on early-life stages of rheophilic fish
BARTOŇ, Daniel
2024 - English 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. Available in the Digital Repository of University of South Bohemia. 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

Evolúcia socio-kultúrnych adaptací člověka: Fylogenetická medzi-kultúrna perspektíva
ŠAFFA, Gabriel
2023 - English 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. Keywords: adaptation; causal inference; cultural evolution; human behavioral ecology; phylogenetics; regression Available in the Digital Repository of University of South Bohemia. 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 - English Available in the Digital Repository of University of South Bohemia. 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 - English 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. Available in the Digital Repository of University of South Bohemia. 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

The role of macrophages in the regulation of systemic metabolism in Drosophila
KREJČOVÁ, Gabriela
2023 - English Macrophages are immensely versatile cells in the mammalian body, fulfilling roles ranging from protection against pathogenic intruders and engulfing apoptotic cells to morphogenesis and maintenance of tissue homeostasis. This impressive functional versatility may be achieved due to plasticity of macrophage cellular metabolism called metabolic polarization. The adoption of different polarization phenotypes by macrophages determines their function and is essential for the health of the organism. Nonetheless, if the cells lose their metabolic plasticity or polarize inadequately to a particular situation, it can lead to the development of chronic pathological states such as metabolic syndrome. Metabolic polarization of immune cells is thus a key factor in determining whether macrophage function within the organism will be adaptive or pathological. Despite Drosophila melanogaster represents a major model organism for immunological studies, the metabolic setup of activated immune cells has not been addressed up to now. The results of this thesis document that Drosophila immune cells undergo metabolic polarization toward aerobic glycolysis when challenged by extracellular bacteria. Mammals alike, this cellular metabolic switch is regulated by the transcription factor HIF1, thus documenting the conservation of this process between insects and vertebrates. Furthermore, we show that the adoption of aerobic glycolysis is directly linked to the production of the signaling factor IMPL2, which induces the mobilization of lipid stores from the fat body via the silencing of insulin signaling. By this mechanism, immune cells secure sufficient nutrients for successful elimination of the pathogen. Moreover, the mammalian ImpL2 homolog IGFBP7 appears to act analogously in the mammalian liver not only during severe infectious states but also in the liver of obese individuals. While such macrophage activity in regulating systemic metabolism is beneficial to the host during bacterial infection, it becomes maladaptive when chronically activated. Further evidence for a metabolism-regulatory role of immune cells has been found during insect metamorphosis and early post-metamorphic development. This thesis documents that during this period, macrophages infiltrate and engulf the histolyzing larval fat body and convert nutrients into storage peptides and lipoproteins. Subsequently, these nutrients are exploited by the maturing adult structures. Macrophages are immensely versatile cells in the mammalian body, fulfilling roles ranging from protection against pathogenic intruders and engulfing apoptotic cells to morphogenesis and maintenance of tissue homeostasis. This impressive functional versatility may be achieved due to plasticity of macrophage cellular metabolism called metabolic polarization. The adoption of different polarization phenotypes by macrophages determines their function and is essential for the health of the organism. Nonetheless, if the cells lose their metabolic plasticity or polarize inadequately to a particular situation, it can lead to the development of chronic pathological states such as metabolic syndrome. Metabolic polarization of immune cells is thus a key factor in determining whether macrophage function within the organism will be adaptive or pathological. Despite Drosophila melanogaster represents a major model organism for immunological studies, the metabolic setup of activated immune cells has not been addressed up to now. The results of this thesis document that Drosophila immune cells undergo metabolic polarization toward aerobic glycolysis when challenged by extracellular bacteria. Mammals alike, this cellular metabolic switch is regulated by the transcription factor HIF1, thus documenting the conservation of this process between insects and vertebrates. Furthermore, we show that the adoption of aerobic glycolysis is directly linked to the production of the signaling factor IMPL2, which induces the mobilization of lipid stores from the fat body via the silencing of insulin signaling. By this mechanism, immune cells secure sufficient nutrients for successful elimination of the pathogen. Moreover, the mammalian ImpL2 homolog IGFBP7 appears to act analogously in the mammalian liver not only during severe infectious states but also in the liver of obese individuals. While such macrophage activity in regulating systemic metabolism is beneficial to the host during bacterial infection, it becomes maladaptive when chronically activated. Further evidence for a metabolism-regulatory role of immune cells has been found during insect metamorphosis and early post-metamorphic development. This thesis documents that during this period, macrophages infiltrate and engulf the histolyzing larval fat body and convert nutrients into storage peptides and lipoproteins. Subsequently, these nutrients are exploited by the maturing adult structures. Keywords: makrofág; metabolismus; imunitní odpověď; polarizace; ImpL2; octomilka; tukové těleso; infiltrace; insulinová rezistence; glukanové částice Available in the Digital Repository of University of South Bohemia. The role of macrophages in the regulation of systemic metabolism in Drosophila

Macrophages are immensely versatile cells in the mammalian body, fulfilling roles ranging from protection against pathogenic intruders and engulfing apoptotic cells to morphogenesis and maintenance of ...

KREJČOVÁ, Gabriela
Jihočeská univerzita v Českých Budějovicích, 2023

Efficient communication of SMEs with geographically limited target groups
ENZ, Christian
2023 - English Předmětem této disertační práce je komunikační chování malých a středních podniků s geograficky vymezenou oblastí podnikání. Jsou sledovány dva výzkumné cíle. Zaprvé je třeba objasnit, zda lze komunikační mix přizpůsobený regionální hospodářské oblasti rozvinout v konkurenční výhodu malých a středních podniků ve srovnání s celostátně nebo globálně působícími korporacemi. Za druhé, pokud tomu tak je, má být vyvinuta metoda, která umožní malým a středním podnikům vytvořit takový účinnější komunikační mix, aniž by musely mít speciální interní odborné znalosti nebo aniž by musely být pověřeny marketingové agentury. Pro dosažení cíle výzkumu bude nejprve analyzováno chování firem a spotřebitelů v regionech Praha, Jižní Čechy, Norimberk a Střední Franky. Na základě rozsáhlého průzkumu lze identifikovat statisticky významnou závislost firemní komunikace na místě sídla společnosti. Podle Cohena existují také střední a silné regionální závislosti ve využívání médií ze strany spotřebitelů. To poskytuje pozitivní odpověď na první výzkumnou otázku. Existují regionální rozdíly ve využívání médií - jak mezi malými a středními podniky, tak mezi příjemci. V souladu s Porterovou teorií konkurence to nabízí potenciál pro optimalizaci, včetně možnosti získat konkurenční výhodu oproti celostátně nebo mezinárodně působícím účastníkům trhu. Dalším cílem výzkumné práce proto bylo vyvinout metriku, která umožní rozhodovacím pracovníkům v malých a středních podnicích posoudit dostupné komunikační příležitosti bez hlubokých marketingových znalostí. V rámci rešerše literatury byla jako vhodný nástroj identifikována metrika vzdálenosti FLOW, která se doposud používala především při vývoji softwaru, a byla upravena tak, aby bylo možné tuto metriku použít k hodnocení marketingových komunikačních kanálů. Vzdálenost FLOW je matematická hodnota, která kvantifikuje pomyslnou vzdálenost mezi komunikující společností a příjemcem. Pokud je hodnota FLOW vysoká, musí sdělení urazit dlouhou cestu od odesílatele k příjemci - komunikační kanál má tedy nízkou úroveň účinnosti. Čím je hodnota FLOW nižší, tím je komunikační prostředek efektivnější. Stanovení vzdálenosti FLOW je založeno na snadno použitelném vzorci - proto je také dosaženo druhého cíle výzkumu. Významu vzdálenosti FLOW je dosaženo proto, že zohledňuje vnímanou intenzitu na straně zákazníka. Za tímto účelem je vnímaný vliv na komunikační kanál stanoven na základě průzkumu mezi spotřebiteli ve čtyřech cílových regionech. Zohledněna je rovněž vhodnost komunikačního kanálu. Za tímto účelem autor kvantifikuje vhodnost jednotlivých komunikačních kanálů pomocí expertního průzkumu. V rámci deskriptivní analýzy je přitom analyzováno 13 marketingových komunikačních kanálů. Zohledněna jsou hlediska nákladů, časové náročnosti, personální náročnosti, potřebné frekvence a potřebných odborných znalostí. The subject of this doctoral thesis is the communication behaviour of SMEs with a geographically defined business area. Two research objectives are pursued. Firstly, it is to be clarified whether a communication mix adapted to regional economic regions can be developed into a competitive advantage for SMEs compared to nationally or globally operating corporations. Secondly, if this is the case, a method will be developed that allows SMEs to create a more effective communication mix without particular in-house expertise or a marketing agency to be commissioned. To achieve the research objective, the behaviour of companies and consumers in the regions of Prague, South Bohemia, Nuremberg and Middle Franconia is first analysed. Based on a large-scale survey, a statistically significant dependence of corporate communication on the company's location can be identified. According to Cohen, there are also medium and firm regional dependencies in media use on the part of consumers. These dependencies provide a positive answer to the first research question. There are regional differences in media utilisation - both among SMEs and recipients. In line with Porter's competition theory, this offers optimisation potential and even the opportunity to gain a competitive advantage over nationally or internationally active market players. A further aim of the research was to develop a metric enabling decision-makers in SMEs to evaluate the available communication options without in-depth marketing expertise. As part of a literature review, the FLOW distance metric, which has primarily been used in software development to date, was identified as a suitable instrument and modified so that this metric can be used to evaluate marketing communication channels. The FLOW distance is a mathematical value quantifying an imaginary distance between the communicating company and the recipient. If the FLOW value is high, a message must travel a long way from the sender to the recipient - the communication channel, therefore, has a low level of effectiveness. The lower the FLOW value, the more efficient the means of communication. The determination of the FLOW distance is based on an easy-to-use formula - which is why the second research objective is also achieved. The significance of the FLOW distance is achieved because it takes into account the perceived intensity on the customer side. For this purpose, a consumer survey in the four target regions determines the perceived influence per communication channel. The suitability of a communication channel is also taken into account. To this end, the author quantifies the suitability of individual communication channels by employing an expert survey. In the process, 13 marketing communication channels are analysed as part of a descriptive analysis. The aspects of costs, time expenditure, personnel intensity, necessary frequency and required expertise are considered. Keywords: malé a střední podniky; prodej; integrovaná komunikace; komunikační mix; konkurenční výhoda; regionální hospodářský prostor; aplikovaná ekonomie Available in the Digital Repository of University of South Bohemia. Efficient communication of SMEs with geographically limited target groups

Předmětem této disertační práce je komunikační chování malých a středních podniků s geograficky vymezenou oblastí podnikání. Jsou sledovány dva výzkumné cíle. Zaprvé je třeba objasnit, zda lze ...

ENZ, Christian
Jihočeská univerzita v Českých Budějovicích, 2023

Butterfly thermoregulation across habitats and climates
LAIRD-HOPKINS, Benita Carmen
2023 - English Global warming, through rising temperatures and changing precipitation patterns, is placing major stress on species and ecosystems. Understanding how species respond to temperature and the mechanisms underpinning thermoregulation can help us predict which species are most vulnerable in the face of warming. In this thesis, I explore how butterflies across different habitats and climates thermoregulate and the mechanisms, including morphology and behaviour, underlaying thermoregulatory ability. Firstly, when comparing the buffering ability of neotropical and temperate butterflies I found that tropical butterflies were able to maintain more stable body temperatures than temperate butterflies, and this was likely driven by their morphology. I also found that temperate butterflies used postural means to raise their body temperature more than neotropical species, likely an adaptation to the cooler air temperatures they experience. Secondly, I showed the importance of butterflies' thermoregulatory abilities at the community level, by comparing thermoregulation of European butterflies across geographic regions and climatic zones. This study highlighted that behavioural thermoregulation, including the use of microclimates and postural means, drives regional differences in butterflies' thermoregulatory abilities. Finally, I utilised the Müllerian mimicry exhibited in Heliconius butterflies to untangle the contributions of morphology and phylogeny in butterfly thermoregulation, investigating thermal traits, including buffering ability, take-off temperature and heating rate. I found that morphology, not phylogeny, was the main driver of thermoregulation in these butterflies. Further, I investigated differences in the thermoregulatory ability of Heliconius butterflies from different habitats. I found that species from colder habitats were able to maintain a more stable body temperature and took off at a lower temperature than those from hotter habitats, suggesting there is local adaptation or acclimation in thermal traits. Overall, this work highlights that species have their own unique thermoregulatory abilities, as a result of the thermal environment they experience, and that thermoregulation is driven by morphology, behaviour and physiology. My findings have important consequences for predicting the impacts of climate change on ectotherms, by highlighting variation in thermal ability which makes some populations and species more vulnerable, while others more resilient. This thesis lays the groundwork for future studies comparing species' thermal traits across climates and habitats, increasing our understanding of how species cope with climate and land-use change. Keywords: Insects; ectotherms; Lepidoptera; butterflies; thermoregulation; ecophysiology; behaviour; microclimates; climate change; tropical regions Available in the Digital Repository of University of South Bohemia. Butterfly thermoregulation across habitats and climates

Global warming, through rising temperatures and changing precipitation patterns, is placing major stress on species and ecosystems. Understanding how species respond to temperature and the mechanisms ...

LAIRD-HOPKINS, Benita Carmen
Jihočeská univerzita v Českých Budějovicích, 2023