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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
721

Potravní preference suchozemských plžů v říčních nivách postižených invazivními rostlinami / Food preferences of land snails in a river flood-plain invoved with invasive plants

Ševčíková, Štěpánka January 2011 (has links)
Food preferences to five most widespread invasive plant species from river floodplains: Impatiens glandulifera, Helianthus tuberosus, Fallopia japonica, F. sachalinensis a F.x bohemica and one native species - U. dioica were studied on two common land snail species. Using three different methods I tried to recognize, whether or not these plants serve as a food source to Succinea putris and Urticicola umbrosus. From histological sectionsit was impossible to identify the plants. The majority of plants don`t provide structures usable for identification of plant in the snail maces. I was able to identify only H. tuberosus and U. dioica undoubtedly, thanks to trichomes. According to the results of laboratory tests, the most important factors for snails food preferences are plant species and the condition of plant material. U. umbrosus consumed much less fresh material than S. putris. Consumption of frozen leaves became larger for both species. The most preffered plant species were U. dioica and H. tuberosus. Only frozen I. glandulifera was consumed. Fallopia spp. were rejected both, fresh or frozen.
722

Postavení ploštěnky Crenobia alpina v trofické síti prameniště / Status of the flatworm Crenobia alpina in the food network of a spring

Reslová, Marie January 2014 (has links)
This work focuses on food preferences of freshwater triclad Crenobia alpina and its position in spring food web. It explores the ability of C. alpina to capture living prey, considers ability of C. alpina and to survive feeding on several types of food. Furthermore it gives view on its occurence and ecological preferences in context of other spring species. One chapter is concerned with taxonomy, anatomy and ecology of Tricladida and C. alpina itself. Short term food-preference experiments show the ability of C. alpina to capture living Lumriculidae and larvae of Ephemeroptera. We don't confirm feeding of C. alpina on living Gammarus, although their occurence in our springs and ecological preferences are similar. C. alpina feeds significantly more on damaged prey without substantial afinity to any species. A year-long experiment on C. alpina in lab conditions finds that this flatworm is able to survive and even breed with nothing but filtred water. This fact connected with the observation of huge densities of flatworms in spring source, opens up a question whether C. alpina can be considered a real predator. Key words: Crenobia alpina, triclad flatworms, food preferences, spring
723

Vnímání krásy savců v ZOO Praha: vliv věku a vzdělání respondentů / Perception of beauty of mammals in Prague ZOO: Influence of respondents' age and education

Poláková, Petra January 2016 (has links)
1 Abstract Every year, the number of species considered as endangered increases, especially due to human activities. Nowadays, captive breeding in zoological gardens becomes an option for their survival in refugees. Zoological gardens function as so-called "Noah's Ark", which has the potential to shelter a large amount of individuals from many species. In the future, this opportunity may give us a chance to reintroduce a species that disappeared in the nature. There are many factors influencing which species will be selected to be kept in zoos, e.g., the IUCN status, taxonomical uniqueness, availability, etc., but it was found that especially the size of the animal and the human aesthetic preferences affect the selection. However, every group of animals is evaluated independently in the terms of beauty, and thus, it is necessary to detect these rules and then to apply them to conservation projects. This thesis examines the factors that influence human aesthetic preferences to mammals, both in terms of the characteristics of animals (their colour and morphology), and in terms of human factors (gender, age, education, residence). It was found that especially the pattern, saturation and overall lightness of the animal affect the evaluation of beauty in mammals. On the other hand, dark colours are evaluated...
724

Role ghrelinu v modulaci neuropatické bolesti / The role of ghrelin in modulation of neuropathic pain

Komárková, Lucia January 2016 (has links)
We are still unable to effectively suppress neuropathic pain, therefore it remains a serious problem. Ghrelin, the orexigenic hormone released by enteroendocrine stomach cells, could contribute to alleviation of the neuropathic pain by its antinociceptive effect. Previous studies have shown that ghrelin prevents development of nociceptive symptoms of neuropathic pain. The aim of our study was to determine whether chronic administration of ghrelin will affect the already fully developed neuropathic pain and differentiate its antinociceptive and analgesic effect. We used a model of chronic constriction injury of the sciatic nerve. We have proven that ghrelin suppressed the already developed thermal and mechanical hyperalgesia, so ghrelin not only prevents the development, but also suppresses the already developed nociceptive symptoms. However analgesia test showed that ghrelin did not affect the temperature preference, neither did induce the place preference. We suppose that ghrelin does not cause analgesia in neuropathic pain and its antinociceptive effect could be caused by anti- inflammatory or neuroprotective action. Key words: Ghrelin, neuropathic pain, chronic constriction injury, preference methods
725

Financování boje proti změně klimatu: Cena zelených dluhopisů a její detereminanty / Financing Climate Action: The Pricing of Green Bonds and Its Determinants

Kortusová, Anna January 2020 (has links)
Green bonds present a promising tool enabling investors in fixed-income mar- kets to finance environmental projects. Yet, the pricing of green bonds with respect to conventional bonds remains an open question. This thesis in- vestigates the existence of a yield differential between green and equivalent conventional bonds in the secondary market. By matching green bonds with synthetic conventional bonds and performing a fixed effects panel regression of the yield spread, we find evidence of a small negative premium associ- ated with green bonds ("green premium"): as a result of high demand from value-seeking investors, the yield of green bonds is on average 1.12 basis points lower than that of their conventional counterparts. The variation in the magnitude of the green premium with bond characteristics is further examined through a cross-sectional regression. We show that external ver- ification of the bond's green credentials and assurance on its post-issuance allocation report significantly increase the estimated green premium. Finally, the green bond's yield seems to decrease in case proceeds are used to finance new projects, while refinancing existing projects results in an increase in the bond's yield. Our findings provide valuable insights into the field of green bond pricing. While the...
726

Into the Comfort Zone: Understanding Swine Thermal Preference

Lindsey A Robbins (10071391) 01 March 2021 (has links)
Exposure to thermal stress can negatively impact an animals' overall welfare, resulting in decreased body condition, lower reproductive success, and in severe cases, mortality. The swine industry has prioritized efficient production and as a result has gained rapid improvements in lean growth and increase litter sizes. Unfortunately, modern swine are unable to cope with the negative effects of heat stress. Thus, it is crucial to understand the preferred temperature of swine to create recommendations on when to initiate mitigation strategies to combat the negative effects of thermal stress. However, several different factors contribute to an animals' thermal comfort and thermal preference will differ based on age, reproductive stage, social context, early life thermal stress, and behavior. Thus, making it exceptionally difficult to classify an animal's thermal comfort zone. These studies aim to highlight how those factors influence thermal comfort in pigs and help guide recommendation polices for housing pigs in their preferred temperatures.<br>
727

Residence, workplace and commute: Interrelated spatial choices of knowledge workers in the metropolitan region of Munich

Zhao, Juanjuan, Bentlage, Michael, Thierstein, Alain 23 September 2020 (has links)
Knowledge workers (KW), as important individual agents who embody, exchange, create and exploit knowledge, contribute to regional competitiveness and growth. To attract and retain them in a region, it is necessary to have a better understanding of their fundamental spatially-related behaviors including residence, workplace, and commute choices. In this study, we depart from a perspective of knowledge typology (analytical-synthetic-symbolic knowledge base) to investigate the heterogeneity of knowledge workers' residence, workplace, and commute choices. The case study was conducted in the metropolitan region of Munich. Various types of data are integrated: structural statistical and individually-based web-survey data; individuals' actual choices and their assessment of importance for each criterion; positional and relational data. We find that symbolic Advanced-Producer-Services (APS) workers tend to reside in central areas and use public transport or active modes to commute. In contrast, synthetic high-tech workers are found in relatively peripheral areas and depend more on cars to reach their workplaces. The spatially-related choices of analytical high-tech and synthetic-APS workers are positioned in between symbolic APS-workers and synthetic high-tech workers. We reach three conclusions: Firstly, the features of the knowledge base are evident in the spatial choices of knowledge workers. Secondly, there is a consistency of characteristics between interrelated spaces surrounding residence, workplace, as well as along the commute path of knowledge workers. Lastly, while the influence of the knowledge base has to be weighed against socio-demographic factors, different groups of knowledge workers clearly display distinct choices of residential location and commute mode. These conclusions may provide insights for urban planners and policy-makers regarding the attraction and retention of knowledge workers.
728

Customer segmentation revisited: The case of the airline industry

Teichert, Thorsten, Shehu, Edlira, von Wartburg, Iwan 20 February 2020 (has links)
Although the application of segmentation is a topic of central importance in marketing literature and practice, managers tend to rely on intuition and on traditional segmentation techniques based on socio-demographic variables. In the airline industry, it is regarded as common sense to separate between business and economy passengers. However, the simplicity of this segmentation logic no longer matches the ever more complex and heterogeneous choices made by customers. Airline companies relying solely on flight class as the segmentation criterion may not be able to customize their product offerings and marketing policies to an appropriate degree in order to respond to the shifting importance and growing complexity of customer choice drivers, e.g. flexibility and price as a result of liberalization in the airline industry. Thus, there is a need to re-evaluate the traditional market segmentation criterion. By analyzing the stated preference data of more than 5800 airline passengers, we show that segmenting into business and leisure (a) does not sufficiently capture the preference heterogeneity among customers and (b) leads to a misunderstanding of consumer preferences. We apply latent class modeling to our data and propose an alternative segmentation approach: we profile the identified segments along behavioral and socio-demographic variables. We combine our findings with observable consumer characteristics to derive pronounced fencing mechanisms for isolating and addressing customer segments receptive for tailored product packages.
729

The neutral zone for mandibular complete dentures: A clinical trial

Geerts, Greta Aimée Virginie Maria January 2016 (has links)
Philosophiae Doctor - PhD / Rehabilitation of edentulous jaws without the option of osseointegrating implants will remain the only treatment option within reach of many older patients for the foreseeable future. Many routine prosthodontic procedures are based on dogmas, because no high-level scientific evidence exists to either accept or reject them, among these is the “neutral zone” (NZ) concept. In spite of paucity of evidence using approved patient-based outcome instruments, it is generally agreed that the NZ should be respected when constructing complete dentures. The purpose of this research project was to determine how shapes of conventional and NZ mandibular dentures differ, and if the two different types of dentures impact differently on oral health–related quality of life by using an accepted oral health-related quality of life instrument as a patient-based outcome. Thirty nine edentulous patients were selected for his prospective, randomised, cross-over, single-blinded clinical trial. Two sets of complete dentures were made for each patient. One denture set was made following conventional biometric guidelines for determining the position of the mandibular posterior denture teeth in relation to the ridge; another set was made following a functional impression of the potential denture space. Each set of dentures was worn for at least two months. A similar number of types of dentures were delivered first. Widths of residual ridges and mandibular denture arches were measured using digital measuring software. Position of denture teeth was related to the ridge. Denture dimensions were compared by means of analysis of variance using the mixed procedure. Using formula of parabola, arch-widths were compared using paired t-tests. Pre- and post-treatment patient feedback was obtained by means of the 20-item Oral Health Impact Profile (OHIP-20) and a preference score. Treatment effect size (ES) was established based on the OHIP-20 scores. Relevant associations among denture dimensions, OHIP-20 scores, preference, age, gender, marital status, education, income, period of edentulousness, and quality of denture-bearing tissue were done using the generalised linear model and correlation analysis. For all statistical analysis, level of significance was determined at p<0.05. The mean age of the sample was 62.3 years. Twenty four patients were female. Mean period of edentulousness was 31 years and mean number of denture sets worn prior to the trial was 2.5. Except for the canine region, NZ dentures were statistically wider than anatomic dentures. The difference in mean widths between the two types of dentures was larger for female patients. Older patients had smaller differences in denture dimensions. More unfavourable denture-bearing tissue was associated with a larger difference in the two types of dentures. Both types of mandibular dentures significantly improved the OHRQoL of patients. Both types of dentures had a high treatment ES. The OHIP-20 instrument could not distinguish a statistical difference in impact on OHRQoL between the two treatment options. There was a minute difference in treatment ES between the two types of treatment. The only domain representing a small clinical benefit between NZ and anatomic dentures was “physical pain”, with the NZ dentures scoring better. There was no correlation between pre- and post-treatment scores for both types of dentures. No significant associations were found between post-treatment OHIP- 20 scores on the one hand and tissue scores, gender, age, education, marital status, period of edentulousness and denture dimension differences on the other hand. Based on OHIP-20 scores, there was a significant association between denture preference and NZ dentures, but not for the other preferences. No significant associations were found between denture preferences on the one hand and tissue scores, gender, age, period of edentulousness and denture dimension differences on the other hand. Even though no significant relationship was found between preference and gender, the majority of female patients preferred the NZ denture and the majority of male patients did not express a preference.Providing new complete dentures improved OHRQoL of edentulous patients. The majority of female patients preferred the NZ compared over the ANA denture. The NZ technique appeared to have a higher positive impact on OHRQoL of female patients compared to male patients.
730

An explorative study on Chinese consumer’s perception and preference for the use of traditional Chinese cultural elements in marketing : - The role of nostalgia

Sun, Jingyi, Huang, Lu January 2020 (has links)
Aim: This study aims to explore the Chinese consumer's perception and preference for the use of traditional Chinese cultural elements (TCCEs) in marketing from two aspects: nostalgia formation and nostalgia preference. Methods: This study adopted the method of qualitative research. The data was collected by the students from the Zhejiang University of Technology through video semi-structured interviews. The four cases of TCCEs products are bottled water, lipstick, pajama, and stationery. They were used in the semi-structured interview. Result &amp; Conclusions: This study concluded that age, gender, and personal experience could influence the formation of nostalgia. Besides, nostalgia advertisements and products can stimulate consumers’ positive emotions, thus generating nostalgia preference. Contribution &amp; implication: From the perspective of companies, nostalgia marketing needs to be customized according to the characteristics of target consumers, i.e., their gender, age, and personal experience. Additionally, the connection between the product and TCCEs should be considered carefully in order to improve the understanding and acceptance of TCCEs products from consumers.

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