The Master‘s thesis deals with the issue of missing VAT in carousel frauds in case-law of the Court of Justice of the European Union and the Supreme Administrative Court of the Czech Republic. Partial issues are identification of missing VAT and subjects in fraudulant supply chain whose right to deduct input VAT can be denied along with question of sanctional or reparational character of denial of right to deduct input VAT. The thesis contains recommended procedure for tax payers to minimize risks related to deduction of VAT.

The moving installation Visible is composed of parts of the classical painting, wooden slats and canvas. It represents the inner walls 8 anonymous portraits of dead children. They represent cruel and incomprehensible pain that a one can commit. Rotating an object is inspired by children's toys, children's carousel and its symbolism and design solutions to commemorate military mobile tent. Object carousel has an octahedral shape with a roof, levitates in the air space, not touching the ground and without a defined border.

5 Abstract Cognitive flexibility is an ability to adapt a behavior according to a dynamic changes in an environment. It belongs to executive functions, along with the processes of working memory, attention, motivation and others. Flexibility is important in the process of changing "stimulus-response" contingency at the time when the initial stimulus no longer leads to reward. According to the nature of the changes we can distinguish three types of cognitive flexibility: reversal learning, intradimensional set shifting and extradimensional set shifting. The processes of cognitive flexibility take place in fronto-striato-thalamic circuit with numerous connections to other brain regions, especially the limbic system. Deficit in cognitive flexibility belongs among cognitive symptoms of schizophrenia, a psychiatric illness we studied in the experimental part of this work using its analogue in rat. The aim of the experimental work was to test cognitive flexibility deficit in the rat model of schizophrenia-like behavior in the Carousel maze in four versions of task with different cognitive load. Animal model of schizophrenia was induced by acute administration of non-competitive NMDA receptor antagonist MK-801 at doses of 0.05 and 0.10 mg/kg i.p. Reversal learning was not damaged in this type of task following the...

Behavioral adaptation to a continuously changing environment is critical for the survival of the animals, but also day-to-day interactions in the human world. The main components maintaining flexibility in cognition and behavior are well-established and depend mostly on proper intercommunication within the prefrontal cortex (PFC) and striatum. Some parts of the PFC are densely innervated by the ventral hippocampus (vHPC), which has a great impact on its functioning. Also, hippocampal-prefrontal circuit dysfunction has been shown to disrupt the integrity of flexible cognition in some neuropsychiatric diseases. Therefore, the exact functional role of this pathway is an indispensable part of the research. The aim of this study was to test the role of the vHPC and the medial PFC (mPFC) in an active place avoidance task on a rotating arena in 1) two flexibility task variants - reversal learning and set- shifting - and 2) the spatial memory retrieval. We inactivated these structures by muscimol (GABAA receptor agonist) in a variety of unilateral, bilateral, and combined local injections. Disrupted performance was apparent in reversal learning in vHPC-inactivated rats. No effect was seen in mPFC-inactivated rats. Impairments after the task acquisition were observed in bilateral vHPC and mPFC inactivations...

The Nogo-A protein belongs among the most important regulatory molecules in the brain, regulating development of neuronal and glial cells, axon guidance and adult synaptic plasticity. Although it has been studied mainly as an obstacle to axon regeneration after CNS injury, it plays a role in many pathological conditions, including neurodegenerative and neuropsychiatric diseases. This work offers a literature review of the current knowledge about functions of Nogo-A and related proteins, and then recapitulates the results of experiments focused on the impact on decreased expression of Nogo-A on behavior in a transgenic rat model. The most important finding is that the Carousel Maze performance, tapping higher cognitive functions such as cognitive coordination and cognitive flexibility, is remarkably impaired in this model, while other cognitive functions, such as spatial navigation and both spatial and non-spatial memory are spared in the Nogo-A deficient rats. The results are discussed in the context of a hypothesis linking Nogo-A mutations or abnormal expression to human schizophrenia. We conclude that the Nogo-A deficient rats constitute a very promising animal model of schizophrenia and deserve further attention. Powered by TCPDF (www.tcpdf.org)

The Nogo-A protein belongs among the most important regulatory molecules in the brain, regulating development of neuronal and glial cells, axon guidance and adult synaptic plasticity. Although it has been studied mainly as an obstacle to axon regeneration after CNS injury, it plays a role in many pathological conditions, including neurodegenerative and neuropsychiatric diseases. This work offers a literature review of the current knowledge about functions of Nogo-A and related proteins, and then recapitulates the results of experiments focused on the impact on decreased expression of Nogo-A on behavior in a transgenic rat model. The most important finding is that the Carousel Maze performance, tapping higher cognitive functions such as cognitive coordination and cognitive flexibility, is remarkably impaired in this model, while other cognitive functions, such as spatial navigation and both spatial and non-spatial memory are spared in the Nogo-A deficient rats. The results are discussed in the context of a hypothesis linking Nogo-A mutations or abnormal expression to human schizophrenia. We conclude that the Nogo-A deficient rats constitute a very promising animal model of schizophrenia and deserve further attention. Powered by TCPDF (www.tcpdf.org)

The increasing use of 3D user interface elements, particularly 3D menus, demonstrates the need to expand research in the field of Human Computer Interaction (HCI) as it pertains to 3D user interfaces. The results of this thesis contribute to the understanding of the cognitive impacts of using 3D menus. Multiple application areas for 3D menus have been identified where memory retention is a critical success factor, but little research has been done in the area of memory retention for 3D menus. The purpose of this thesis is to investigate if the use of 3D carousel menus increases retention of information over 2D menus and if is there a gender effect with these results. A three factor split-plot (one-between subject factor and two-within subject factors) experiment was designed to test if menu dimension, content type, and gender are significant factors in memory retention and to determine if there are any interactions between these factors. The results of the experiment revealed that dimension and gender are not significant factors in the retention of information and none of the interactions of dimension (2D vs. 3D), gender, and content were significant. Several subjects’ questionnaire responses demonstrated that the menu dimension they perceived to better aid retention was 3D; however these results were not statistically significant. While these results showed that within the boundaries chosen the use of a 3D menu neither promotes nor degrades memory retention, there are still a number of questions that need to be answered regarding the use of 3D menus and their effect on other cognitive processes.

Invasive species represent a major concern; they can result in serious ecological and economic losses and are recognised as one of the most serious threats to global species diversity. Plant invasions are of particular concern in New Zealand, which has high proportions of both naturalised and endemic plant species. In this thesis I focussed on the invasive plant Hieracium lepidulum, an exotic weed introduced from Europe to New Zealand prior to 1941. It is invasive in a variety of habitats in the South Island, where it has steadily increased in distribution and abundance over the last 50 years, and is thought to have detrimental impacts on native plant communities. I investigated factors influencing its invasion success and tested for impacts on native plant communities, making extensive use of existing plots into which H. lepidulum was experimentally introduced in 2003. I examined how community richness, turnover, resource availability and propagule pressure of the invader interacted to determine the invasion success of H. lepidulum. Results differed markedly above and below treeline. Above treeline, plots with higher richness and turnover were more invaded; below treeline, plots with higher available light were more invaded. In both habitats, these findings were modified by the influence of propagule pressure; at low propagule pressure, site characteristics were non-significant in explaining invasion success, while at higher propagule pressure these effects became significant. To test for impacts resulting in altered community composition and structure, I looked for changes in community richness, diversity and evenness subsequent to H. lepidulum introduction. As impacts may be more apparent at fine spatial scales, I made measurements at a 5 x 5 cm cell scale in addition to the established 30 x 30 cm plot scale. Plot species richness increased from 2003 to 2009 and a component of this increase was associated with H. lepidulum density. Other relationships between the plant community and H. lepidulum were generally non-significant. Results showed that H. lepidulum has had no negative effects on community richness, evenness or diversity. Despite being able to opportunistically colonise grassland sites with high turnover, and forest sites subject to canopy disturbance, dependant on propagule pressure, it appears H. lepidulum has not impacted community composition or structure.

Mervärdesskattebedrägerier inom den gemenskapsinterna handeln är idag ett utbrett problem. I och med den inre marknadens framväxt och det gemensamma mervärdesskattesystemets struktur har nya former av mervärdesskattebedrägerier uppstått. Då den inre marknaden öppnades 1993 togs den fysiska tullkontrollen bort och kvar återstod endast en administrativ kontroll. Till dess att en fullständig harmonisering kan genomföras på mervärdesskatteområdet tillämpas destinationslandsprincipen på gemenskapsintern handel mellan näringsidkare. För att undvika dubbelbeskattning har regler om gemenskapsinterna förvärv framtagits. Dessa innebär att köparen beskattas i sitt hemland och att säljaren undantas från skatteplikt i sitt hemland. En form av mervärdesskattebedrägeri som utnyttjar mervärdesskattesystemet och bristerna i informationsutbytet mellan medlemsstaterna är karusellbedrägerier. I stora drag kan karusellbedrägerier beskrivas som transaktioner med samma varor som säljs i rask takt mellan olika företag i olika länder. I samband med dessa försäljningar betalar något eller några av företagen inte in utgående mervärdesskatt, samtidigt som andra företag i kedjan har rätt till avdrag för ingående mervärdesskatt. Staten förlorar därmed mervärdesskatteintäkter. Karusellbedrägerier har behandlats i rättspraxis. I Optigen-domen fastställs att avdragsrätten för en part i god tro inte påverkas av bedrägligt beteende i tidigare eller senare led i transaktionskedjan. I Kittel-domen stadgas att en skattskyldig person som kände till eller borde ha känt till att dennes transaktion ingick i ett mervärdesskattebedrägeri skall anses vara medgärningsman och därmed vägras avdragsrätt. I uppsatsen utreds huruvida principen om förbud mot förfarandemissbruk kan vara tillämplig på karusellbedrägerier. Principen om förbud mot förfarandemissbruk har utvecklats för att angripa konstruerade transaktioner vars enda syfte är att genom missbruk av gemenskapslagstiftningen erhålla förmåner. I Halifax-domen fastslås att denna princip är tillämpbar på mervärdesskatteområdet. Vår slutsats är att principen om förbud mot förfarandemissbruk inte kan tillämpas på någon part i ett karusellbedrägeri. Vi anser att varken en part i god tro eller en part i ond tro angående bedrägeriet kan uppfylla kriterierna för principen. Det finns olika tillvägagångssätt för att angripa karusellbedrägerier. Inom EG används främst informationsutbyte som strategi för bedrägeribekämpning. Organisationer såsom SCAF och OLAF har också betydelse för bekämpningen. Även medlemsstaterna har på olika sätt försökt bekämpa bedrägerierna. De har bland annat använt sig av omvänd skattskyldighet och solidariskt betalningsansvar. Vi anser att de administrativa åtgärderna är avgörande för bekämpning av karusellbedrägerier. De mer genomgripande alternativen, såsom omvänd skattskyldighet och solidariskt betalningsansvar, bör endast användas då det är uppenbart att de administrativa åtgärderna inte räcker till. / Today, VAT fraud is a widely spread problem among intra-Community trade. Due to the growth of the common market and the structure of the harmonized VAT system, new forms of VAT fraud have arisen. The opening of the common market, in 1993, led to the abolition of physical border controls. The combination of physical and administrative controls was replaced by only administrative control. Until the VAT system is completely harmonized the principle of destination will be applied to intra-Community business-to-business transactions. Regulations on intra-Community transactions have been developed to avoid double taxation. These regulations mean that the purchaser will be taxed in its state of origin, and that the seller will be exempted from taxation in its state of origin. Carousel fraud is a form of VAT fraud that makes use of the VAT system and the lack of exchange of information between the member states. In general terms VAT fraud can be described as transactions with the same goods that are being sold at high speed between different companies in different countries. In connection to these sales one or more of the companies do not pay the output VAT, at the same time other companies in the chain of supply have the right to deduct input VAT. Due to this, the state will loose VAT revenues. Carousel fraud has been dealt with in EC case law. It is established in the Optigen judgment that the right, of a taxable person, to deduct input VAT cannot be affected by any other taxable person’s fraudulent behavior in the chain of supply as long as the taxable person did not know or have any means of knowledge of the fraud in question. The Kittel judgment states that a taxable person, who knew or should have known that, by his purchase, he was participating in a transaction of VAT fraud, should be seen as a participant in that fraud and therefore be refused entitlement to the right to deduct. This thesis examines whether the principle of prohibiting abusive practice is applicable to carousel fraud. The Halifax judgment states that the principle also applies to the sphere of VAT. The principle of prohibiting abusive practice has been developed to attack transactions of purely artificial nature, which only purpose is to obtain advantages by abusing the Community law. However, our conclusion is that the principle of prohibiting abusive practice cannot be applied to anyone in a chain of transactions that constitutes carousel fraud. Our opinion is that neither a taxable person in god faith nor a taxable person in bad faith can meet the criteria of the principle. There are different ways to approach carousel fraud. Within the EC, exchange of information and various organisations for anti fraud are being used to deal with the problem. The member states have also, in various ways, tried to handle carousel fraud. They have for example used reverse charge and joint liability. We believe that administrative measures are crucial to combat carousel fraud. More radical alternatives such as reverse charge and joint liability should not be used unless it is obvious that the administrative measures do not suffice.

<p>Mervärdesskattebedrägerier inom den gemenskapsinterna handeln är idag ett utbrett problem. I och med den inre marknadens framväxt och det gemensamma mervärdesskattesystemets struktur har nya former av mervärdesskattebedrägerier uppstått. Då den inre marknaden öppnades 1993 togs den fysiska tullkontrollen bort och kvar återstod endast en administrativ kontroll. Till dess att en fullständig harmonisering kan genomföras på mervärdesskatteområdet tillämpas destinationslandsprincipen på gemenskapsintern handel mellan näringsidkare. För att undvika dubbelbeskattning har regler om gemenskapsinterna förvärv framtagits. Dessa innebär att köparen beskattas i sitt hemland och att säljaren undantas från skatteplikt i sitt hemland.</p><p>En form av mervärdesskattebedrägeri som utnyttjar mervärdesskattesystemet och bristerna i informationsutbytet mellan medlemsstaterna är karusellbedrägerier. I stora drag kan karusellbedrägerier beskrivas som transaktioner med samma varor som säljs i rask takt mellan olika företag i olika länder. I samband med dessa försäljningar betalar något eller några av företagen inte in utgående mervärdesskatt, samtidigt som andra företag i kedjan har rätt till avdrag för ingående mervärdesskatt. Staten förlorar därmed mervärdesskatteintäkter. Karusellbedrägerier har behandlats i rättspraxis. I Optigen-domen fastställs att avdragsrätten för en part i god tro inte påverkas av bedrägligt beteende i tidigare eller senare led i transaktionskedjan. I Kittel-domen stadgas att en skattskyldig person som kände till eller borde ha känt till att dennes transaktion ingick i ett mervärdesskattebedrägeri skall anses vara medgärningsman och därmed vägras avdragsrätt.</p><p>I uppsatsen utreds huruvida principen om förbud mot förfarandemissbruk kan vara tillämplig på karusellbedrägerier. Principen om förbud mot förfarandemissbruk har utvecklats för att angripa konstruerade transaktioner vars enda syfte är att genom missbruk av gemenskapslagstiftningen erhålla förmåner. I Halifax-domen fastslås att denna princip är tillämpbar på mervärdesskatteområdet. Vår slutsats är att principen om förbud mot förfarandemissbruk inte kan tillämpas på någon part i ett karusellbedrägeri. Vi anser att varken en part i god tro eller en part i ond tro angående bedrägeriet kan uppfylla kriterierna för principen. Det finns olika tillvägagångssätt för att angripa karusellbedrägerier. Inom EG används främst informationsutbyte som strategi för bedrägeribekämpning. Organisationer såsom SCAF och OLAF har också betydelse för bekämpningen. Även medlemsstaterna har på olika sätt försökt bekämpa bedrägerierna. De har bland annat använt sig av omvänd skattskyldighet och solidariskt betalningsansvar. Vi anser att de administrativa åtgärderna är avgörande för bekämpning av karusellbedrägerier. De mer genomgripande alternativen, såsom omvänd skattskyldighet och solidariskt betalningsansvar, bör endast användas då det är uppenbart att de administrativa åtgärderna inte räcker till.</p> / <p>Today, VAT fraud is a widely spread problem among intra-Community trade. Due to the growth of the common market and the structure of the harmonized VAT system, new forms of VAT fraud have arisen. The opening of the common market, in 1993, led to the abolition of physical border controls. The combination of physical and administrative controls was replaced by only administrative control.</p><p>Until the VAT system is completely harmonized the principle of destination will be applied to intra-Community business-to-business transactions. Regulations on intra-Community transactions have been developed to avoid double taxation. These regulations mean that the purchaser will be taxed in its state of origin, and that the seller will be exempted from taxation in its state of origin.</p><p>Carousel fraud is a form of VAT fraud that makes use of the VAT system and the lack of exchange of information between the member states. In general terms VAT fraud can be described as transactions with the same goods that are being sold at high speed between different companies in different countries. In connection to these sales one or more of the companies do not pay the output VAT, at the same time other companies in the chain of supply have the right to deduct input VAT. Due to this, the state will loose VAT revenues. Carousel fraud has been dealt with in EC case law. It is established in the Optigen judgment that the right, of a taxable person, to deduct input VAT cannot be affected by any other taxable person’s fraudulent behavior in the chain of supply as long as the taxable person did not know or have any means of knowledge of the fraud in question. The Kittel judgment states that a taxable person, who knew or should have known that, by his purchase, he was participating in a transaction of VAT fraud, should be seen as a participant in that fraud and therefore be refused entitlement to the right to deduct.</p><p>This thesis examines whether the principle of prohibiting abusive practice is applicable to carousel fraud. The Halifax judgment states that the principle also applies to the sphere of VAT. The principle of prohibiting abusive practice has been developed to attack transactions of purely artificial nature, which only purpose is to obtain advantages by abusing the Community law. However, our conclusion is that the principle of prohibiting abusive practice cannot be applied to anyone in a chain of transactions that constitutes carousel fraud. Our opinion is that neither a taxable person in god faith nor a taxable person in bad faith can meet the criteria of the principle.</p><p>There are different ways to approach carousel fraud. Within the EC, exchange of information and various organisations for anti fraud are being used to deal with the problem. The member states have also, in various ways, tried to handle carousel fraud. They have for example used reverse charge and joint liability. We believe that administrative measures are crucial to combat carousel fraud. More radical alternatives such as reverse charge and joint liability should not be used unless it is obvious that the administrative measures do not suffice.</p>