Дисертації з теми "LDL transport"

AIMS: Macrophages (MPs) and vascular smooth muscle cells (VSMCs) closely interact within the growing atherosclerotic plaque. An in vitro co-culture model was established to study how MPs modulate VSMC behaviour. METHODS AND RESULTS: MPs were exposed to fluorescence-labelled-acetylated LDL (FL-acLDL) prior to co-culture with VSMCs. Fluorescence microscopy visualized first transport of FL-acLDL within 6 h after co-culture implementation. When MPs had been fed with FL-acLDL in complex with fluorescence-labelled cholesterol (FL-Chol), these complexes were also transferred during co-culture and resulted in cholesterol positive lipid droplet formation in VSMCs. When infected with a virus coding for a fusion protein of Rab5a and fluorescent protein reporter (FP) to mark early endosomes, no co-localization between Rab5a-FP and the transported FL-acLDL within VSMCs was detected implying a mechanism independent of phagocytosis. Next, expression of lysosome-associated membrane glycoprotein 1 (LAMP1)-FP, marking all lysosomes in VSMCs, revealed that the FL-acLDL was located in non-acidic lysosomes. MPs infected with virus encoding for LAMP1-FP prior to co-culture demonstrated that intact fluorescence-marked lysosomes were transported into the VSMC, instead. Xenogenic cell composition (rat VSMC, human MP) and subsequent quantitative RT-PCR with rat-specific primers rendered induction of genes typical for MPs and down-regulation of the cholesterol sensitive HMG-CoA reductase. CONCLUSION: Our results demonstrate that acLDL/cholesterol-loaded lysosomes are transported from MPs into VSMCs in vitro. Lysosomal transfer results in a phenotypic alteration of the VSMC towards a foam cell-like cell. This way VSMCs may lose their plaque stabilizing properties and rather contribute to plaque destabilization and rupture.

Le cholesterol des plaques d'atherosclerose provient des lipoproteines de basse densite (ldl) d'origine plasmatique. Dans cette these, apres avoir decrit l'histoire de la decouverte des ldl et de leur implication dans l'atherosclerose, nous avons etudie dans l'aorte thoracique isolee de lapin, le role: 1) des recepteurs ldl dans le transport et la degradation des ldl. 2) de l'hyperpression sur le transport et la distribution des ldl. Dans la premiere etude, en comparant le devenir de ldl normales (ldln) a celui de ldl methylees, qui perdent leur capacite a etre reconnues par les recepteurs ldl, nous avons demontre que les recepteurs ldl sont actifs dans la paroi arterielle, qu'ils participent a la degradation des ldl, la partie interne de l'artere etant cataboliquement plus active que la media externe. Cette activite catabolique des recepteurs ldl pourrait prevenir l'accumulation de ldl dans la paroi arterielle a l'origine du processus atherosclereux. Dans la deuxieme etude, nous avons montre que l'hyperpression transmurale provoque une accumulation de ldl tres importante dans les couches internes de la paroi arterielle due a l'action synergique d'une augmentation de la permeabilite endotheliale, d'une augmentation de la convection des ldl, et d'une compaction de la media. Ces effets pourraient representer un des mecanismes par lesquels l'hypertension accelere le processus atherosclereux

The accumulation of low density lipoproteins within the arterial wall is associated with process of atherogenesis. Moreover, it is commonly accepted, that the development of the atherosclerotic plaque is enhanced by the biomechanical factors, such as hypertension and low wall shear stress. In addition to medical experiments, computational simulations of the LDL transport in the vascular wall are an important tool in the study of atherosclerosis. Simulations of the LDL transport affected by that biomechanical factors can improve the understanding of mechanisms responsible for the atherogenesis. In this thesis the extended theoretical model of the LDL transport in the arterial wall is introduced. Proposed model for the first time take into account two mentioned biomechanical factors simultaneously. In this model arterial wall is considered as a medium composed of four homogeneous porous layers. The transport of macromolecules in such structure is described by the volume-averaged advectiondiffusion- reaction equation. The first part of the thesis contains biological and physical basis of the modeling. In this part the process of atherogenesis affected by biomechanical factors is presented. Then the transport processes in porous media are discussed. In the main part of this thesis the extended four layer model of the LDL transport in the arterial wall is presented. In this section, differences between proposed model and other models, known from literature are emphasized. Moreover, the procedure of transport parameters estimation is described in details. It is important because in literature there are some extremely different transport parameters sets for the LDL transport in the vessel wall. The most important part of this section is the description of methods, which allow to impose biomechanical factors to the modelling. In the next part of the thesis results obtained in the modeling are discussed. This section is divided into two main parts. In the first one the influence of biomechanical factors on one-dimensional LDL concentration profiles within the arterial wall is investigated. In the second part, the example of applying the proposed model to analysis of clinical data is presented. The CT based geometry of the right coronary artery was used in calculations. To sum up, in the thesis it has been shown that it is possible to accurate model the LDL transport with good agreement with experiments. It can be the first step for clinical usage of theoretical calculations of the LDL transport in the arterial wall. Moreover, the analysis of the influence of biomechanical factors on this transport has allowed us to draw conclusions about reasons of the LDL accumulation process in the vessel wall.

Mestrado em Gestão de Recursos Humanos
O presente Trabalho Final de Mestrado reflete no desenvolvimento de um estágio curricular, com duração de três meses na área de Recursos Humanos, departamento de Recrutamento e Seleção da empresa Macon Transportes Lda. O objetivo deste trabalho passa pela apresentação detalhada das atividades relacionadas com o processo de recrutamento e seleção desenvolvidas na empresa Macon. O desafio atual é a condução do processo de contratação que, na maioria das vezes é falho por falta de critérios e instrumentos adequados e que na maioria das vezes pode gerar grandes perdas financeiras e perda de tempo. Desta feita, a primeira parte do relatório é dedicado ao enquadramento teórico, seguindo-se uma breve apresentação da instituição (MACON Transportes, Lda.), na terceira parte, foram apresentadas e detalhadas as atividades realizadas ao longo do estágio, e subsequentemente na quarta foram pormenorizadas as atividades desenvolvidas na empresa no período do estágio e por fim, foram elaboradas as discussões e conclusões e apresentadas as limitações e sugestões. O objetivo final do relatório de estágio é descrever as funções exercidas e as tarefas efetuadas, explicitando a relação entre a formação obtida ao longo do curso de mestrado e a sua aplicação no trabalho na empresa.
This present Masters Degree Final Work, reflects the development of an curricular internship, with a duration of three months in Human Resources area, department of Recruitment and selection of Macon Transport Lda company. The objective of this work goes through the detailed presentation of activities related to the procedure for recruitment and selection developed in Macon Company. . The current challenge is to leading the hiring process that most of the times it´s flawed for lack of criteria and instrument that in most of the times can cause great financial and time losses. By this, the first part of the report is dedicated to the theoretical framework, followed by a brief presentation of the institution (MACON Transportes, Lda.), in the third part, we were presented and detailed the activities carried out throughout the internship, and subsequently in the fourth they were detailed the activities developed at the company at internship period and finally were prepared the discussions and conclusions and brought the limitations and suggestions. The ultimate goal of internship report is to describe the functions exercised and performed tasks, explaining the relation between the training obtained along master course and its application at work in the company

Le problème de localisation de hubs et tournées combinées (Hub Location-Routing Problem, HLRP), concerne la conception d’un réseau de transport performant entre de nombreuses origines (fournisseurs) et destinations (clients). Ce système est basé sur la localisation de plates formes (hubs) permettant de concentrer les flux et l’organisation de tournées pour la collecte des marchandises des fournisseurs et la distribution vers les clients. Nous étudions le cas spécifique du HLRP à capacités et allocations uniques (CSAHLRP) et de processus de tournées de collecte et distribution séparés. Nous proposons un modèle de programmation linéaire mixte (MILP) et un Algorithme Mémétique (MA) pour ce problème en vue de la minimisation du coût total du réseau de transport. De plus, nous étendons le modèle MILP pour le cas bi-objectif afin de minimiser à la fois le coût total et les émissions de CO2 du transport. Notre algorithme Mémétique (MA) et adapté et combiné à un algorithme génétique de tri non-dominé élitiste rapide (NSGAII) afin de déterminer des approximations du front de Pareto. Enfin, nous proposons une procédure en deux phases pour résoudre le HLRP mono objectif, comportant la résolution du problème de localisation des hubs (HLP) suivi pour chaque hub de la résolution de deux problèmes de tournées relatifs à la collecte et la livraison. Notre modèle MILP mono objectif est décomposé et notre MA est adapté pour résoudre le problème suivant ces deux étapes. Un ensemble d’instances de différents tailles et caractéristiques a été développée afin de conduire des expérimentations et de valider nos approches de résolution de ces différents problèmes
We study the Hub Location-Routing Problem (HLRP) aiming at the design of an efficient freight transportation network for LTL (less-than-truck) transport between many origins (suppliers) and destinations (clients). Such a network relies on the location of consolidation hubs, the organization of routings for the collection/distribution of freight from suppliers to hubs and from hubs to clients, as well as direct shipment of consolidated freight between hubs. We focus on the Capacitated Single Allocation Hub Location-Routing Problem (CSAHLRP) in the case of distinct collection and delivery processes. We propose mixed integer linear programming (MILP) model and a Memetic Algorithm (MA) to solve the problem for minimizing the total cost of the network. Then we extend the model into a bi-objective model for minimizing both the total cost and CO2 emissions of transport. A modified memetic algorithm (MA) combined with a fast elitist non-dominated sorting genetic algorithm (NSGAII) is developed to capture the trade-off between minimizing total cost and CO2 emissions and exhibit approximations of the Pareto front. At last, a two step procedure is proposed to solve the single-objective HLRP based on a hub location problem (HLP) and two distinct vehicle routing problems for suppliers and clients allocated to each hub by the first step. Our single objective MILP model is decomposed accordingly and our MA is adapted to solve the HLRP following these two steps. A data base of instances of different sizes and characteristics has been developed in order to conduct extensive experiments for solving all these problems using the different solution techniques and validate our approaches

Thesis (MSc)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: A series of di- and mono-substituted acyl(aroyl) thioureas were examined for the extraction and transportation of Au(III). Two-phase metal ion extraction experiments were employed to investigate the extraction behaviour of these ligands. The effect of varying ligand concentration on the extraction trend of these ligands was investigated. The results show that the different substituent groups on the benzoyl ring can affect the extraction pattern of the metal. Furthermore, the alkyl substituents on the thiourea moiety and varying the ligand concentration have an influence on the percentage of metal ion extracted. With the exception of the H2L2(N,N-di-propyl-N'- benzoylthiourea ) ligand the di-alkyl substituted thioureas were more efficient for the metal ion extraction than the mono-alkyl ligands. In almost all the experimental set ups there was reduction of the Au(lIl) to Au(l) and Au(O) but it was more pronounced with HL3 (N,N-di-(2-hydroxyethyl)-N'-benzoylthiourea). Transport experiments were also conducted, the experimental set up for transportation was a concentric type cell involving a 3-phase system - 2 aqueous phases ( source and receiving phase) separated by a chloroform membrane incorporating the ligand. The transport results however only gave a satisfactory result of about 5% of gold transported by the HL1 (N,N-dibutyl-N'-benzoylthiourea). All other ligands attempted resulted in metal ion being present in the organic phase, but no metal ion present in the receiving phase. To help drive the transport of the metal ion to the receiving phase CN-, S203 2- and perchloric acid were incorporated into the receiving phase. The transport results were not enhanced with these substances being present in the aqueous receiving phase. The aqueous source and receiving phases were analyzed by flame atomic absorption spectroscopy (FAAS). Finally the N,N-diethyl-N'-camphanoylthiourea (HL10) ligand and its complex with Au(l) were synthesised. Single crystals of the complex were grown for X-ray crystallography and the crystal and molecular structure of the complex was determined. The complex crystallizes in the monoclinic space group P21. The cell parameters are a = 10.7356(7)A b = 16.3443(11)A c = 10.9268(7)A f3 = 103.1450(10t , and final R-factor of 1.76%. The coordination sphere around Au(l) shows a nearly linear arrangement of sulphur and chloride.
AFRIKAANSE OPSOMMING: In hierdie proefskrif is In aantal mono- en di-gesubstitueerde asiel(ariel) thioureums ondersoek vir die transportasie en ekstraksie van Au(III). Twee-fase metaalioon vloeistof-vloeistof ekstraksie eksperimente is gebruik om die ekstraksie patroon van hierdie ligande te ondersoek. Die effek van verskillende ligand konsentrasies op die ekstraksie neiging van hierdie ligande is ondersoek. Resultate toon dat die verskillende substituente op die benziel ring die ekstraksie patroon van die metaalioon beïnvloed. Verder, is gevind dat die alkiel substituente op die thioureum saam met varierende ligand konsentrasies geensins die metaalioon ekstraksie beïnvloed nie. Met die uitsondering van H2L2 (N,N-dipropiel-N'-benzielthioureum) is die di-alkiel gesubstitueerde ligande meer effektief vir metaalioon ekstraksie in vergelyking met die mono-alkiel ligande. In baie van die eksperimente is In reduksie van Au(llI) na Au(l) en Au(O) gesien en dit is baie duidelik met ligand HL3 (N,N-di(2- hidroksie-etiel)N'-benzielthioureum). Alle waterige fases is ge-analiseer met gebruik van Atoomabsorpsie Spektroskopie (AAS). Transportasie eksperimente is ook uitgevoer met gebruik van In drie-fase selsisteem. Twee waterige fases (bron- en ontvang-fase) is geskei met die chloroform membraan fase wat die ligande bevat. Hierdie eksperimente het net In 5% Au(lll) transportasie getoon met HL1(N,N-dibutiel-N'-benzielthioureum). Daar was geen transportasie van Au(lIl) met enige van die ander ligande. Analise van die twee waterige fases het getoon dat die metaalioon eindelik goed ge-ekstraeer is en is teenwoordig in die membraan fase. Om die transportasie van Au(lIl) aan te spoor, is CN-, s2ol- en perchloorsuur in die ontvang-fase geinkorporeer. Die resultate was geensins beïnvloed nie. N,N-di-etiel-N'-kamfonielthioureum (HL10)ligande en die kompleks daarvan met Au(l) is ook gesintetiseer. Enkel-kristalle van die kompleks is verkry en X-straal kristallografiese analiese is onderneem. Hierdie kompleks kristalliseer in die monokliniese ruimtegroep P21,met a =10.7356(7)Á, b=16.3443(11)Á, c=10.9268(7)Á en ~=103.1450(10t. Die finale R-faktor is 1.76%. Die koordinasie om Au(l) toon In liniêre geometrie met swael en chloor.

The LDD model was first applied to Arsenic concentration profiles determined in surface diffusion experiments by Yoshida and Arai [1]. The new method presented is based on a mathematical convolution with a delta-function-like concentration profile. By comparing the LDD approximation of post-surface diffusion with post-implant diffusion experiments, the same LDD model parameter r is found to hold for both experimental arrangements. This work found that post-implant diffusivity is concentration dependant and this might indicate an anomalous diffusion mechanism for Arsenic.

La Teoria di Densità Funzionale (DFT) e la sua versione dipendente dal tempo (TDDFT) sono strumenti largamente usati per simulare e calcolare le proprietà statiche e dinamiche di sistemi con elettroni interagenti. La precisione del metodo si basa su una serie di approssimazioni degli effetti di exchange correlation fra gli elettroni, descritti da un funzionale della sola densità di carica. Nella presente tesi viene testata l'affidabilità del funzionale Mixed Localization Potential (MLP), una media pesata fra Single Orbital Approximation (SOA) e un potenziale di riferimento, ad esempio Local Density Approximation (LDA). I risultati mostrano capacità simulative superiori a LDA per i sistemi statici (curando anche un limite di LDA noto in letteratura come fractional dissociation) e dei progressi per sistemi dinamici quando si sviluppano correnti di carica. Il livello di localizzazione del sistema, inteso come la capacità di un elettrone di tenere lontani da sé altri elettroni, è descritto dalla funzione Electron Localization Function (ELF). Viene studiato il suo ruolo come guida nella costruzione e ottimizzazione del funzionale MLP.

The bedload transport of mixed size sediment is an important process in river engineering. Bedload transport controls channel stability and has a significant bearing on the hydraulic roughness of the channel. The prediction of bedload transport traditionally relies upon defining some critical value of fluid force above which particles of a particular diameter are assumed to be put into transport. The suggestion here is that the transport of bed material is size dependent with large grains being more difficult to remove from the bed surface than small grains and that all grains of the same size start to move under identical conditions. While it is relatively straightforward to assess the forces required to engender transport in a bed of uniform size grains, it is not so simple where there are a number of different grain sizes present. Multitudinous experimental studies have revealed that where there are a number of grain sizes present, large grains tend to become mobilised under lower fluid forces and small grains mobilised under higher fluid forces than those required for beds of uniform material. These results led to the development of so-called hiding functions which are used to model the variation of particle mobility with its relative size within the mixture. These functions derive their name from the tendency of large grains to shelter smaller grains from the action of the flow. Determining the relative mobility of each fraction in a mixture under given hydraulic conditions is the key to predicting how the composition of the bed load will relate to that of the bed surface material. Experiments were carried out in a rectangular, glass sided channel, in a sediment recirculation mode, under varying hydraulic conditions with a set of six different sediment mixtures. Laser Doppler Anemometry (LDA) was used to attain instantaneous velocity measurements at a number of locations in the flow. A Laser Displacement Meter was used to measure the detailed topography of small sections of the bed surface. Novel analysis techniques facilitated the determination of the grain size distribution of the bed surface by a grid-by-number method. The minimum force required to entrain each grain could also be estimated by a grain pivoting analysis. This information represents the resistance of the bed grains to erosion by flowing water. With the critical conditions for the bed grains known, it is possible to estimate the proportion of each fraction entrained from the bed surface under given hydraulic conditions. To estimate the bedload composition it is first necessary to scale by the proportion each size comprises on the bed surface and then, by a function of grain diameter to account for size dependency of travel velocity. For mean hydraulic conditions the proportion of the bed mobilised can be simply determined by inspection of a cumulative distribution of critical conditions. In reality, although it may be possible to entrain some grains at the mean velocity/shear stress, the majority of transport may be anticipated to occur during high magnitude events. Turbulence may be incorporated by adopting a probabilistic approach to the prediction of grain entrainment. By considering the joint probability distribution of bed shear stress and critical shear stress, one may attain the probability of grain entrainment. Comparison of the probability of erosion of each fraction facilitates a prediction of the bedload composition. Results show that the probabilistic approach provides a significant improvement over deterministic methods for the prediction of bedload composition.

The LDD model was first applied to Arsenic concentration profiles determined in surface diffusion experiments by Yoshida and Arai [1]. The new method presented is based on a mathematical convolution with a delta-function-like concentration profile. By comparing the LDD approximation of post-surface diffusion with post-implant diffusion experiments, the same LDD model parameter r is found to hold for both experimental arrangements. This work found that post-implant diffusivity is concentration dependant and this might indicate an anomalous diffusion mechanism for Arsenic.

As localizações dos terminais e as rotas de entrega que partem desses terminais são decisões importantes que surgem na concepção de redes de transporte de carga fracionada. Nesses casos, dois problemas independentes precisam ser tratados: o problema da localização de instalações (LAP) e o problema da roteirização dos veículos (VRP). Este trabalho apresenta um modelo matemático para resolver o LAP e o VRP de forma integrada, ou seja, para a resolução do problema de Localização/Roteirização (Location Routing Problem - LRP). De acordo com a literatura, a abordagem integrada do LRP fornece melhores resultados do que a solução do LAP e do VRP separadamente. O modelo foi testado e aplicado em um caso real de Many-to-Many com Multiplos elos LRP, respeitou as restrições e o nível de serviço exigido e propiciou melhoria nos resultados para a empresa de transporte no qual foi aplicado. Os resultados do modelo também foram melhores do que os resultados apresentados por um software líder de mercado.
In the Less Than Truck Load (LTL) operations both the location of facilities and the routing of vehicles are important decisions for the optimal design of the related logistics network. Two interdependent problems arise: the Location Allocation Problem (LAP) and the Vehicle Routing Problem (VRP). This paper presents a mathematical model to solve the LAP and the VRP simultaneously on an integrated way, such as the so-called Location-Routing Problem (LRP). According to the literature the LRP integrated approach provides better results than considering the LAP and the VRP separately. The model was tested and applied to a real case of Many-to-Many with Multi-Echelons LTL Location-Routing Problem respecting the constraints and the required service level standard and provided better results for the company in which it was tested. The model results also were better than the results presented by market-leading software.

Un modèle complet permettant de simuler la dynamique d'un nano-aérosol est présenté et discuté. On considère une équation Eulérienne de type « Diffusion-Inertia » réécrite en moments en incluant un terme source de coagulation. Le phénomène de dépôt est pris en compte par l'intermédiaire d'une condition aux limites sur le flux de moments à la paroi. L'expression de la granulométrie en moments permet d'obtenir une très bonne efficacité de calcul et rend ainsi le modèle utilisable pour des applications industrielles ou en santé au travail. L'implémentation de cette approche dans un code de CFD est validée sur des cas simples par comparaison avec une méthode des classes ainsi que des données expérimentales. La méthode des moments n'introduit pas de biais particulier et les résultats numériques sont en accord avec les résultats expérimentaux. Un nouveau dispositif expérimental, qui consiste en une enceinte ventilée, est également proposé afin de maîtriser au mieux l'écoulement et de caractériser la morphologie des agrégats générés. La confrontation entre les résultats numériques et expérimentaux met en évidence le fait que la détermination des paramètres fractals est un élément clé de la modélisation
A complete CFD model for nano-aerosol dynamics is presented and discussed. It consists in an Eulerian "Diffusion-Inertia" equation including a coagulation source term which is rewritten in terms of moments. Deposition phenomenon is taken into account by means of a boundary condition on the flux of moments at walls. The moment transformation allows good computational performances and makes thus the model tractable for industrial and occupational health applications. The implementation of this approach into a CFD code is assessed for simple cases by comparison with sectional approach results and experimental data. These comparisons show that the method of moments does not induce particular bias and that numerical results are in good agreement with available experimental data. An experimental set-up, which consists in a ventilated chamber, is also proposed for allowing a good control of the flow and for allowing the investigation of aggregates morphology. The confrontation between numerical and experimental results highlights that the determination of the fractal parameters is a modelling key point

Mestrado em Gestão de Recursos Humanos
O presente relatório tem como objetivo central identificar os tipos de recompensas (monetária ou não monetária) utilizadas pela empresa Macon Transportes, Lda, conhecer e identificar a relação existente entre as variáveis em estudo e a satisfação no trabalho dos seus motoristas. Para dar coerência ao raciocínio no decurso do seu desenvolvimento, cedemos privilégio, em primeiro lugar a abordagens acerca dos conceitos sobre o sistema de remunerações, benefício, satisfação, por conseguinte a relação entre as teorias dos conceitos e a aplicação na prática empresarial, dando ênfase à parte prática desenvolvida no decorrer da fase de estágio. Para melhor aprofundamento, percepção, identificação e conhecimento das variáveis em destaque, inquirimos uma amostra que foi costituída por 90 motoristas das várias áreas de serviço, notificados por meio de entrevista (ver guião de entrevista anexo 3 e 4). Os resultados obtidos evidenciam que os colaboradores e particularmente os motoristas da Macon, apesar das dificuldades, estão satisfeitos com o que recebem salarialmente em relação à função que desempenham, e mostram-se mais satisfeitos ainda, com os benefícios e com as condiçoes de trabalho, oferecidas pela organização. Não obstante a atual situação da crise económica do País que assola profundamente quer de forma direta ou indireta as organizações, aos trabalhadores e a população em geral.
This report is mainly aimed to identify the types of rewards (monetary or non-monetary) used by the company Macon Transportes, Lda., Know and identify the relationship between the study variables and job satisfaction of their drivers. To give coherence to the reasoning in the course of its development, we give privilege, first approaches about the concepts of the remuneration system, benefit, satisfaction, therefore the relationship between the theories of concepts and application in business practice, emphasizing the practice of developed during the training phase. For deeper understanding, perception, identification and knowledge of the highlighted variable, we inquire a sample was qu costituida by 90 drivers from various areas of service, contacted through interviews and questionnaires (interview guide in Annex 3 and 4). The results show that the employees and particularly drivers of Macon, despite the difficulties, are satisfied with the salary they receive in relation to their function, and show even more satisfied with the benefits and the conditions of work, offered by the organization. Despite the current situation of the country's economic crisis plaguing deeply either directly or indirectly organizations, workers and the general population. Not having many options for employment improvements in the short and medium term.

The goal of this diploma thesis is to define the maritime container transport and some of the important aspects, which are closely related to it. The next goal is to describe the single steps of the maritime container transport (LCL) from port in Hong Kong, to compare import of LCL consignment from port in Hong Kong or port in Nansha and to decide which of these option is better for the customer in Czech republic, speaking of time and cost view. This goal is shown on the specific business case in DB Schenker company.

Research question: What initiatives does Lidl Sweden implement in the area of environmental sustainability?                          Purpose: The purpose of this research is to investigate what initiatives Lidl has developed and how the company implemented its corporate social responsibility in the direction of environmental sustainability. The purpose is also to compare the company’s activities with the guidelines of the EU Environment Commission and theoretical frameworks developed by previous research, and, as the result, to provide recommendations to the Lidl management. As well the purpose is to review the general improvement patterns within the food retail industry. Method: The research is made by using a qualitative method with a deductive approach. In order to present quality information in the study, a case design was chosen. The empirical analysis includes four interview transcriptions, secondary data and documentation, as well as a comparison to the theoretical concepts in the descriptive analysis. Conclusion: The responsibility and awareness of the improvement of the environmental sustainability is vital in the food retail industry. Indeed, it was found that aspects such as product and supplier’s control, the use of resources, transportation and distribution, as well as waste management and information communication to the employees and customers are considered as important aspects of the contribution for the environmental impact reduction. Lidl Sweden has developed and implemented some initiatives towards environmental sustainability, as well regarding the corporate social responsibility. However, there are some suggested actions that can be taken in order to excel the development.

The topic of this thesis is groupage service in maritime transportation and its use for export out of Czech Republic. In the theoretical and methodological part I am defining the main terms in maritime transportation and maritime transportation in general. In the thesis I am describing the role of maritime transportation in the Czech Republic emphasized by statistics. Further I am writing about containerization and main container types because those are very important for the groupage service. In the practical part I am describing the processes of exports groupage service (LCL) within company Austromar spol. s r.o. on which I am applying business cases to to show how those processes work in reality. One of the business cases is transportation of hazardous material. In the last part of thesis I am comparing the direct and non-direct container with example of the freight charges calculation.

Introdução: A quantidade e o tipo de gordura alimentar exercem importante influência no desenvolvimento de doença cardiovascular (DCV) e podem contribuir para o desenvolvimento de esteatose hepática. Os ácidos graxos saturados e trans são consensualmente apontados como aterogênicos; já os poli-insaturados parecem exercer ação antiaterogênica. Com relação a esteatose hepática, sabe-se que os ácidos graxos saturados estão associados com o seu desenvolvimento; porém, a ação dos ácidos graxos trans na gênese e no desenvolvimento de esteatose hepática não está totalmente elucidada. Neste estudo, avaliou-se o efeito do consumo de dietas enriquecidas com ácidos graxos saturados (SAT), poli-insaturados (POLI) ou trans (TRANS) sobre componentes envolvidos na indução e na progressão da placa aterosclerótica, bem como sobre o desenvolvimento da doença hepática gordurosa não alcoólica. Métodos: Camundongos com ablação gênica para o receptor de LDL (LDLr-KO) foram alimentados com dietas hiperlipídicas (40% do valor calórico total sob a forma de gordura), enriquecidas com ácidos graxos SAT, POLI ou TRANS por 16 semanas e ao final submetidos a: 1) análises plasmáticas: colesterol total (CT), triglicérides (TG), insulina, glicose, aspartato aminotransferase (AST) e alanina aminotransferase (ALT), interleucina-6 (IL-6), fator de necrose tumoral-? (TNF-alfa) e perfil de lipoproteínas; 2) determinação da lesão aterosclerótica: área de lesão (Oil Red-O), conteúdo de ATP-binding cassette transporter A1 (ABCA1) e infiltrado de macrófagos (imuno-histoquímica), colocalização de ABCA1 e macrófagos (microscopia confocal) e conteúdo de colágeno (Picrosirius-Red) na raiz aórtica; 3) conteúdo de CT, colesterol éster (CE) e colesterol livre (CL) na aorta total; 4) macrófagos peritoneais foram tratados com lipopolissacarídeo (LPS), e IL-6, TNF-alfa e interleucina-10 (IL-10) medidas no meio de cultura; 5) no fígado: grau da doença hepática gordurosa não alcoólica, concentração de CT e TG e expressão de RNA mensageiro (mRNA) de PPAR-gama, PPAR-gama, SREBP-1c, MTP, CPT-1 e ABCA1 por RT-qPCR; 6) determinação do conteúdo de tecido adiposo visceral e subcutâneo na carcaça. Resultados: O consumo de dieta não diferiu entre os grupos; comparado à dieta POLI, TRANS induziu menor ganho de peso refletido por menor conteúdo de tecido adiposo. TRANS induziu hepatomegalia, desenvolvimento de esteato-hepatite não alcoólica (NASH) e piora da sensibilidade insulínica (evidenciada pelo índice HOMAIR). As concentrações de AST e ALT não diferiram entre os grupos. A dieta TRANS elevou a expressão de mRNA de genes relacionados à lipogênese hepática (PPAR-gama e SREBP-1c) comparada à SAT e POLI e reduziu a expressão de MTP comparada à dieta POLI. Não houve diferença entre os grupos com relação à expressão de genes envolvidos na oxidação hepática de lípides (PPAR-gama e CPT-1). As concentrações plasmáticas de CT e TG foram maiores no grupo TRANS comparado a SAT e POLI. POLI apresentou menor área de lesão, infiltrado de macrófagos e conteúdo de ABCA1 comparados a SAT e TRANS. Macrófagos e ABCA1 não se colocalizaram na área de lesão. O conteúdo de CT na parede arterial foi menor no grupo POLI comparado a TRANS; CL foi menor no grupo POLI comparado a SAT e TRANS; CE não diferiu entre os grupos. Comparado a POLI, SAT e TRANS apresentaram maior conteúdo de colágeno e núcleos necróticos na placa aterosclerótica. A concentração plasmática de IL-6 não diferiu entre os grupos; já a concentração de TNF-alfa foi maior nos grupos POLI e TRANS em comparação a SAT. Em relação à resposta inflamatória de macrófagos ao LPS, POLI e TRANS apresentaram maiores concentrações de IL-6 e TNF-alfa comparadas a SAT. POLI apresentou menores concentrações de IL-10 em comparação aos demais grupos. A expressão hepática de ABCA1 não diferiu entre os grupos. Conclusão: O consumo de dieta TRANS induziu perfil lipídico proaterogênico, hipercolesterolemia, hipertrigliceridemia, hiperglicemia e severo desenvolvimento de aterosclerose, além de hepatomegalia, maior acúmulo hepático de lípides e desenvolvimento de NASH. Por outro lado, POLI preveniu o desenvolvimento de aterosclerose, independentemente de sua ação inflamatória.
Introduction: The amount and type of dietary fat play important roles on the development of cardiovascular disease (CVD) and on the development of hepatic steatosis. Saturated (SAT) and trans (TRANS) fatty acids are known as pro-atherogenic, while the polyunsaturated (POLY) fats seem to exert an antiatherogenic action. Regarding hepatic steatosis, it is known that SAT are associated with its development, however, the role of TRANS in the genesis and development of hepatic steatosis is not fully undestood. This study evaluated the effect of the intake of diets enriched with SAT, POLY or TRANS on the parameters involved in the progression of the atherosclerotic plaque and also on the development of the nonalcoholic fatty liver disease (NAFLD). Methods: LDL receptor knock-out (LDLR-KO) male mice were fed for 16 weeks a high fat diet (40% of calories as fat) enriched with SAT, POLY or TRANS, for 16 weeks. The following parameters were mesured: 1) plasma: total cholesterol (TC), triglyceride (TG), insulin, glucose, aspartate aminotransferase (AST) and alanine amino transferase (ALT), interleukin-6 (IL-6), tumor necrosis factor- ? (TNF-?) and lipoprotein profile; 2) atherosclerotic lesion - lesion area (Oil Red-O), ATP-binding cassette transporter A1 (ABCA1) content and macrophage infiltration (immunohistochemistry), co-localization of ABCA1 and macrophages (confocal microscopy) and collagen content (Picrosirius-Red); 3) TC, cholesteryl ester (CE) and free cholesterol (FC) content of the total aorta; 4) interleukin-6 and 10 (IL-6 and IL-10) and TNF-alfa in the culture medium of peritoneal macrophages after treatment with lipopolysaccharide (LPS); 5) liver: degree of fat liver disease, concentration of TC and TG and mRNA expression (RT-qPCR) of PPAR-gama, PPAR-gama, SREBP-1c, MTP, ABCA1 and CPT-1; 6) visceral and subcutaneous adipose tissue contents in the carcass of the animals. Results: Food intake did not differ amongst the groups, however, compared to POLY, TRANS induced less weight gain, due to lower adipose tissue content. TRANS induced hepatomegaly, nonalcoholic steatohepatitis (NASH) and worsening of insulin sensitivity, as evidenced by the index HOMAIR. The concentrations of ALT and AST did not differ among groups. TRANS increased the mRNA expression of the hepatic lipogenic genes (PPAR-gama and SREBP-1c) compared to the SAT and POLY and reduced the mRNA expression of MTP compared to POLI. There was no difference among the groups regarding the mRNA expression of genes involved in hepatic lipid oxidation (PPAR-gama and CPT-1). Plasma concentrations of TC and TG were higher in TRANS compared to SAT and POLY. POLY showed lower arterial lesion area, macrophage infiltration and ABCA1 content compared to SAT and TRANS. ABCA1 and macrophages did not colocalize in the lesion area. The TC content in the arterial wall was lower on POLY compared to TRANS; FC was lower on POLY compared to SAT and TRANS; CE did not differ among groups. Compared to POLY, SAT and TRANS showed higher collagen content and necrotic core in atherosclerotic plaques. The plasma concentration of IL-6 did not differ among groups, however, TNF-alfa plasma concentration was higher in POLY and TRANS compared to SAT. Regarding the macrophage inflammatory response to LPS, POLY and TRANS showed higher concentrations of IL-6 and TNF-alfa compared to SAT. Moreover, POLY had the lowest concentration of the anti-inflammatory cytokine IL-10. The hepatic expression of ABCA1 did not differ amongst the groups. Conclusion: TRANS induced pro-atherogenic lipid profile, hypercholesterolemia, hypertriglyceridemia, hyperglycemia, and severe atherosclerosis, and in addition, elicted hepatomegaly, increased hepatic lipid accumulation and NASH. On the other hand, POLY prevented the development of atherosclerosis, independently of their pro-inflammatory activity.

In recent years, application of confluent jets for design of ventilation supply devices has been studied. Similarly, numerus studies have been made on the potential and application of variable air volume (VAV) in order to reduce the energy demand of ventilation systems. This study investigates the combination of supply devices based on confluent jets and VAV, both in terms of the nearfield flow behavior of the device and the impact on thermal comfort, indoor air quality and energy efficiency on a classroom-level space when the airflow rate is varied. The method used in this study is an experimental field study where the confluent jets-based supply devices were compared to the previously installed displacement ventilation. The field study evaluated the energy efficiency, thermal comfort and indoor air quality of the two systems. In the case of the confluent jets supply devices, airflow rate was varied in order to see what impact the variation had on the performance of the system for each airflow rate. Furthermore, the confluent jets supply devices were investigated both experimentally and numerically in a well insulated test room to get high resolution data on the particular flow characteristics for this type of supply device when the airflow rate is varied. The results from the field study show nearly uniform distribution of the local mean age of air in the occupied zone, even in the cases of relatively low airflow rates. The airflow rates have no significant effect on the degree of mixing. The thermal comfort in the classroom was increased when the airflow rate was adapted to the heat load compared to the displacement system. The results lead to the conclusion that the combination of supply devices based on confluent jets can reduce energy usage in the school while maintaining indoor air quality and increasing the thermal comfort in the occupied zone. The results from the experimental and numerical study show that the flow pattern and velocity in each nozzle is directly dependent on the total airflow rate. However, the flow pattern does not vary between the three different airflow rates. The numerical investigation shows that velocity profiles for each nozzle have the same pattern regardless of the airflow rate, but the magnitude of the velocity profile increases as the airflow increases. Thus, a supply device of this kind could be used for variable air volume and produce confluent jets for different airflow rates. The results from both studies show that the airflow rate does not affect the distribution of the airflow on both near-field and room level. The distribution of air is nearly uniform in the case of the near-field results and the room-level measurement shows a completely uniform degree of mixing and air quality in the occupied zone for each airflow rate. This means that there is potential for combining these two schemes for designing air distribution systems with high energy efficiency and high thermal comfort and indoor air quality.
Under senare tid har applikation av Confluent jets för design av tilluftsdon studerats. Många studier har även utförts över potentialen av att applicera variabelt luftflöde (VAV) för att minska energianvändningen i ventilationssystem. Denna studie undersöker möjligheten att kombinera Confluent jets-don med VAV, både med avseende på den lokala flödesbilden och dess påverkan på termisk komfort, luftkvalitet och energieffektivitet i en klassrumsmiljö där luftflödes varieras. Denna studie baseras dels på en experimentell fältstudie där tilluftsdon baserade på Confluents jets jämfördes med befintliga deplacerande tilluftsdon. Fältstudien utvärderade energieffektiviteten, den termiska komforten och luftkvaliteten för båda typerna av tillluftsdon. Confluent jets-donen testades under varierat luftflöde för att se påverkan av flödesvariationen på ventilationens prestation under de olika flödena. Utöver fältstudien testades Confluent jets-donen experimentellt och numeriskt i ett välisolerat test-rum för få den detaljerade flödeskarakteristiken för den här typen tilluftsdon vid varierat luftflöde. Resultaten från fältstudien visar på en jämn fördelning av den lokala luftsmedelåldern i vistelsezonen, även för fallen med relativt låga luftflöden. Luftflöden har ingen signifikant effekt på omblandningen. Den termiska komforten i klassrummet ökade när luftflödet anpassades efter värmelasten jämfört med de deplacerande donen. Slutsatsen från fältstudien är att kombinationen av VAV och Confluent jets-don kan användas för att minska energianvändningen på skolan och bevara luftkvaliteten och den termiska komforten i vistelsezonen. Resultaten från den experimental och numeriska studien visar luftflödet och lufthastigheten i varje enskild dysa är direkt beroende på det totala luftflödet genom donet. Dock är flödesfördelningen mellan dysorna oberoende av de tre olika luftflödena. Den numeriska undersökningen visar att flödesprofilen för varje dysa är konstant trots att flödet varieras, men amplituden för varje profil ökar med en höjning av luftflödet. Det betyder att tilluftsdon av den här typen kan användas med VAV för att producera Confluent jets för olika luftflöden. Resultaten från båda studierna visar att luftflöde inte påverkar fördelningen av luften vare sig längs luftdonen eller på rumsnivå. Fördelningen av luften är nästan helt jämn längs donen och på rumsnivå är omblandningen och luftkvalitet den samma för varje luftflöde. Det betyder att det finns potential för att kombinera det här två teknikerna för att designa luftdistribueringssystem med hög energieffektivitet och hög termisk komfort med god luftkvalitet.

L’athérosclérose débute par l’accumulation de cholestérol dans les cellules des parois artérielles, formant des plaques d’athéromes. LRP1 protège contre la maladie en inhibant l’accumulation intracellulaire de cholestérol et nous avions montré qu’une signalisation Wnt5a était impliquée dans cette inhibition. Le projet de thèse consistait à caractériser les mécanismes moléculaires de cette inhibition et à vérifier l’effet athéroprotecteur de Wnt5a. Nous avons montré in vitro et in vivo que Wnt5a inhibe l’accumulation de cholestérol via la stimulation de son export et l’inhibition de sa synthèse endogène. Nous avons ensuite observé que l’invalidation de Wnt5a spécifiquement dans les CMLv de souris LDLR-/- conduit à une augmentation des lésions athéromateuses après un régime riche en cholestérol, confirmant alors son rôle athéroprotecteur. Nos travaux ont ainsi permis de révéler le potentiel de Wnt5a en tant que cible thérapeutique dans le traitement contre l’athérosclérose
Protects against intracellular cholesterol accumulation and we identified the secreted protein Wnt5a as a partner of this inhibitory effect of LRP1. The aim of this thesis is to determine the molecular mechanisms by which the LRP1/Wnt5a signaling pathway prevents cholesterol accumulation in cells and to study the antiatherogenic potential of Wnt5a. We first showed in vitro and in vivo that Wnt5a decreases cellular cholesterol content by stimulating its efflux through the induction of cholesterol transporters expression and by down-regulating the expression of HMGCoA-reductase. Then we used mice deleted for Wnt5a specifically in smooth muscle cells, which present more atherosclerotic lesions than control mice after a high cholesterol diet. This confirms that Wnt5a protects against atherosclerosis and could be an interesting therapeutic target in the treatment of the disease

AIMS: Macrophages (MPs) and vascular smooth muscle cells (VSMCs) closely interact within the growing atherosclerotic plaque. An in vitro co-culture model was established to study how MPs modulate VSMC behaviour. METHODS AND RESULTS: MPs were exposed to fluorescence-labelled-acetylated LDL (FL-acLDL) prior to co-culture with VSMCs. Fluorescence microscopy visualized first transport of FL-acLDL within 6 h after co-culture implementation. When MPs had been fed with FL-acLDL in complex with fluorescence-labelled cholesterol (FL-Chol), these complexes were also transferred during co-culture and resulted in cholesterol positive lipid droplet formation in VSMCs. When infected with a virus coding for a fusion protein of Rab5a and fluorescent protein reporter (FP) to mark early endosomes, no co-localization between Rab5a-FP and the transported FL-acLDL within VSMCs was detected implying a mechanism independent of phagocytosis. Next, expression of lysosome-associated membrane glycoprotein 1 (LAMP1)-FP, marking all lysosomes in VSMCs, revealed that the FL-acLDL was located in non-acidic lysosomes. MPs infected with virus encoding for LAMP1-FP prior to co-culture demonstrated that intact fluorescence-marked lysosomes were transported into the VSMC, instead. Xenogenic cell composition (rat VSMC, human MP) and subsequent quantitative RT-PCR with rat-specific primers rendered induction of genes typical for MPs and down-regulation of the cholesterol sensitive HMG-CoA reductase. CONCLUSION: Our results demonstrate that acLDL/cholesterol-loaded lysosomes are transported from MPs into VSMCs in vitro. Lysosomal transfer results in a phenotypic alteration of the VSMC towards a foam cell-like cell. This way VSMCs may lose their plaque stabilizing properties and rather contribute to plaque destabilization and rupture.

Atherosclerosis is an arterial disease that occurs due to the build-up of lipids, cholesterol and other substances in the arterial wall, collectively called plaque, leading to narrowing of the vessel lumen and, in time, disruption to the blood supply. The study of flow through atherosclerotic vessels is especially important since plaques not only cause a reduction in the vessel lumen but can rupture from the arterial wall, causing a blood clot in the vessel that may ultimately lead to heart attack or a stroke. Elevated level of oxidated low density lipoprotein (LDL) is a known risk factor associated with the genesis of atherosclerosis in arterial walls. Previous studies reported in literature have explored the transport of LDL through the arterial wall using analytical and mathematical models. In this work, we have presented a computational framework for the study of LDL transport in the lumen and the porous arterial wall. We have employed a four-layer arterial wall model and used governing equations to model the transport of LDL. We have used physiological parameters for the wall layers from literature and have validated the model based on the calculated filtration velocities and LDL concentration profiles in the arterial wall. We have further used this established model to study the effect of change in permeability and pressure on the LDL concentration. We have also studied the effect of pulsatile flow on the transport of LDL through the porous walls to examine the validity of the initial assumption of steady state and have seen that pulsation increases the time averaged net flux of LDL species by about 20%. We have next modeled a drug-eluting stent (DES), which is one of the popular remedies to cure atherosclerosis. The validation of DES model is followed by a combined study to analyze the effect of stent placement on LDL transport. Although there is no chemical reaction between the drug and LDL, we have noticed recirculation zones near the stent strut which result in accumulation of LDL molecules in the arterial wall. Future studies are aimed at incorporating variable porosity and permeability and a stenosed region in the geometry. The deformation of arterial wall due to pulsatile blood flow may lead to alteration of wall properties, which can give a realistic view of macromolecular transport.

Generation of foam cells, an essential step for reverse cholesterol transport (RCT) studies, uses the technique of receptor dependent macrophage loading with radiolabeled acetylated Low Density Lipoprotein (Ac-LDL). In this study, we used the ability of a biologically relevant detergent molecule, Lysophosphatidylcholine (Lyso PtdCho), to form mixed micelles with cholesterol or cholesteryl ester (CE) to generate macrophage foam cells. Fluorescent or radiolabelled cholesterol / Lyso PtdCho mixed micelles were prepared and incubated with RAW 264.7 or mouse peritoneal macrophages. Results showed that such micelles were quite stable at 4°C and retained the solubilized cholesterol during one month storage. Macrophages incubated with cholesterol or CE (unlabeled, fluorescently labeled or radiolabeled) / Lyso PtdCho mixed micelles accumulated CE as documented by microscopy, lipid staining, labeled oleate incorporation, and by thin layer chromatography (TLC). Such foam cells unloaded cholesterol when incubated with high density lipoprotein (HDL) and not with oxidized HDL (Ox-HDL). We propose that stable cholesterol or CE / Lyso PtdCho micelles would offer advantages over existing methods. Oxidative stress is associated with heart failure (HF). Previously our research group observed that the patients with low left-ventricular ejection fraction showed accumulation of high level of oxidized LDL (Ox-LDL) when compared with the heart failure patients with normal range of ejection fraction (EF). HDL is known to be atheroprotective and one of its important antioxidative functions is to protect LDL from oxidative modifications. However, HDL itself undergoes oxidation and Ox-HDL becomes functionally poor. It is expected to have a diminished ability to promote reverse cholesterol transport. Therefore, it was hypothesized that the quality of HDL present in the patients with EF would more compromised than those present in the patients with normal EF. Functionality of HDL was evaluated by measuring its cholesterol efflux capacity from foam cells generated in vitro. Functionality of HDL, which is strongly related to the oxidative modifications of HDL was further estimated by measuring paraoxonase 1 (PON1) enzyme activity associated with HDL. Higher the PON1 activity and RCT ability, better is the functionality of HDL.
Ph.D.
Doctorate
Molecular Biology and Microbiology
Medicine
Biomedical Sciences

O presente caso de estudo tem como finalidade analisar e fundamentar a estratégia da empresa Transportes Heitor & Carlos, Lda, desde a sua fundação até a actualidade evidenciando e caracterizando o meio-envolvente. Com base na revisão da literatura, na teoria dos custos de transacção, o modelo da Escola de Uppsala, a teoria das redes e os estudos de Michael Porter, possibilitaram uma análise detalhada e fundamentada da empresa THC. Numa primeira fase analisou-se a evolução do sector dos transportes de mercadorias a nível nacional e europeu, evidenciando a crescente importância do modo rodoviário nas operações de transporte. Procedeu-se à caracterização do sector logístico, representando um mercado mais restrito, com elevado potencial permitindo oferecer um serviço que acrescente valor ao cliente. Na análise interna definiu-se a visão, a missão, os valores e as politicas, com o intuito de potenciar o crescimento do negócio através da combinação positiva de pontos fortes e oportunidades e procurando minimizar a combinação negativa de ameaças e fraquezas. O processo de internacionalização na THC, resulta essencialmente de uma estratégia de seguimento do cliente, melhorando a relação empresa-cliente e eliminando barreiras. Simultaneamente a empresa reforça a sua posição na Península Ibérica e aproxima-se do Centro da Europa.
The case study herein presented aims its goal to a thorough analysis at the grounded strategy operated by the company Transportes Heitor & Carlos, Lda., from its establishment up to the present day, outstanding and depicting its surroundings. Based upon revised literature namely on the transaction cost theory, the Uppsala School model, the networking theory and Michael Porter’s studies, it was possible to accomplish a detailed and grounded analysis of THC. A first approach was devoted to the study of the evolution of the national and Europeanwide freight transport sector, focusing on the crescent importance of highways in road transports operations. A characterization of the logistical sector was carried out for it represents a more narrowed market with a high-level potential, thus allowing a more value-added service offered to the client. The inside analysis of the company gave the definition of the vision, mission, values and policies adopted, aiming the potential business growth through the positive association of the strongest key points and opportunities, and questing for the minimization of negative association of possible threats and weaknesses. The internationalization process of THC is a basic result of a follow-up client strategy that conducts to a company-client relationship improvement thus excluding barriers. At the same time, the firm reinforces its posture in the Iberian Peninsula and becomes closer to the centre of Europe.

碩士
明志科技大學
電機工程系碩士班
104
In recent years, there are many new technologies such as optical communication, cloud technology, smart appliances, etc. These techniques often require high bandwidth capacity in fiber-optic transmission systems. The traditional optical double sideband (ODSB) modulation could cause severe optical dispersion in radio-on-fiber (ROF) system. Optical single sideband (OSSB) modulation is usually used to solve it. OSSB modulation can suppress the power dissipation effectively and extend the signal transmission distance. In addition a new cutting edge technology, Free-Space Optical (FSO), is born to fulfill the needs of high speed transmission. FSO is able to avoid the radio jam problem. We propose two kinds of architectures in this paper. Architecture I：In the proposed scheme, the downlink signal is modulated by the optical single sideband (OSSB) signal. The downlink wavelength is reused for uplink in Base station (BS). Based on injection-locked Distributed Feedback (DFB) Lasers and stimulated Brillouin scattering (SBS) achieve OSSB modulation. The two kinds of technologies fall on frequency band approximately nearby 10.8 GHz. The frequency band is used to enhance OSSB signal. After pass through an optical interleaver (IL). The even and odd port of the IL is used to separate the downstream and upstream signal, respectively. In our proposed bidirectional transmission system, the performances of bit error rate analysis are good. Architecture II：Vertical-cavity surface-emitting laser (VCSEL) based free-space optical (FSO) communication employing three-stage injection-locked technique and the afocal scheme is proposed and experimentally demonstrated. The three-stage injection-locked technique, which can significantly increase the resonant frequency of the VCSEL, is expected to provide higher transmission rate in FSO communication. The afocal scheme, which can reduce the beam size of laser beam, is expected to provide longer free-space link in FSO communication. Such VCSEL based FSO communication provides the advantages of optical wireless links for longer transmission distance and higher transmission rate, which is thoroughly useful for high-speed light-based WiFi (LiFi) applications.

碩士
國立臺北科技大學
光電與通訊產業研發碩士專班
97
A full-duplex ROF transport system based on mutually FP LDs is proposed and demonstrated. Transmission performances over a-40 km standard SMF for full-duplex transmission were investigated. Good performance of BER was achieved in our proposed systems. We directly modulate the FP LDs in mutually injection-locked scheme instead of using expensive external modulator and sophisticated optical carrier suppression technique; it reveals an outstanding alternative with advantages in simplicity and cost.

The Chlamydiaceae are Gram-negative, obligate intracellular bacteria that are significant pathogens of humans and animals. Intracellularly, the bacteria reside in a membrane-bound vacuole, called the inclusion, from which they manipulate host processes to create a niche optimal for survival and propagation. Acquisition of host-derived lipids is essential for chlamydial growth, yet the source of lipids and mechanisms of trafficking to the inclusion are not well-established. The inclusion avoids interaction with several classical membrane and lipid transport pathways. In a functional genomic screen to identify host modulating chlamydial proteins, our lab identified cytosolic lipid droplets (LDs) as potential target organelles of Chlamydia. LDs are postulated to function in many cellular processes, such as lipid metabolism and transport, membrane trafficking, and cell signaling; therefore, we hypothesized that LDs may be important for Chlamydia pathogenesis as a source of lipids or as a platform for regulating other cellular functions. Here, we characterize the interaction between eukaryotic LDs and the chlamydial inclusion.

We find that LDs are recruited to the Chlamydia inclusion, chlamydial infection disrupts neutral lipid homeostasis, and pharmacological prevention of LD formation inhibits chlamydial replication. Chlamydia produces proteins (Ldas) that localize with LDs in yeast and mammalian cells when transiently expressed and are exported out of the inclusion to peripheral lipid-rich structures during infection. By electron microscopy and live cell imaging, we observe the translocation of intact LDs into the Chlamydia inclusion lumen. Biochemical and microscopic analysis of LDs from infected cells reveals that LD translocation may occur at specialized subregions of the inclusion membrane. The Chlamydia Lda3 protein is implicated in LD tethering to the inclusion membrane, and displacement of the protective coat protein, ADRP, from LD surfaces. This phenomenon could provide access for lipases to the LD core for utilization by the replicating bacteria. Additionally, the functional domains of Lda3 involved in binding to LD and inclusion membranes are identified.

In these studies, we identify eukaryotic lipid droplets (LDs) as a novel target organelle important for Chlamydia pathogenesis and describe a unique mechanism of whole organelle sequestration not previously observed for bacterial pathogens. These results represent a fundamental shift in our understanding of host interactions with the chlamydial inclusion, and may represent a new area for research in the field of cellular microbiology.

Dissertation

O presente trabalho centra-se na implementação de uma abordagem Lean no departamento de manutenção de uma empresa na área dos transportes. Esta empresa dedica-se ao serviço internacional de transporte de viaturas. Este departamento é responsável por garantir que toda a frota da empresa se encontra em bom estado de conservação e em condições de executar o seu trabalho de uma forma eficiente. Em primeiro lugar, foi realizada uma pesquisa teórica, para que todas as alterações que fossem efetuadas, fossem suportadas em casos de estudo de sucesso, e representassem uma melhoria para a empresa e ainda que estas fossem bem fundamentadas. Posteriormente, foi realizada uma análise para que se pudessem compreender as prioridades de melhoria dentro deste departamento. Após a análise das possíveis melhorias, procedeu-se à implementação da ferramenta 5S, para que fosse possível reestruturar a organização bem como todos os processos, tais como o armazém de ferramentas e de peças de reserva, tendo sempre subjacente a filosofia Lean. Por fim, efetuou-se a reanálise das decisões tomadas, verificando as melhorias que resultaram das alterações e quais os projetos que, seguindo este pensamento, poderiam advir no futuro para que a empresa possa prosseguir com uma base de trabalho de melhoria contínua ao longo do tempo.

O leite é um produto de elevada qualidade nutricional, ocupando lugar de destaque na dieta humana especialmente na infância. É constituindo principalmente por água, possuindo ainda teor considerável de proteína e gordura, sendo que o valor destes parâmetros varia considerando a espécie produtora. Este produto alimentar deve chegar ao seu consumidor nas melhores condições de salubridade e segurança, garantido as melhores condições de temperatura e de execução de procedimentos capazes de assegurar tal resultado. Todo o processo produtivo deve ser monitorizado sendo que a realização deste estágio incidiu sobre o processo de recolha e transporte do leite. Na entidade acolhedora, Transportes Quintino Augusto Branco & Filhos Lda, sucederam-se diversos procedimentos com o objetivo último de garantir a qualidade do produto no momento de entrega à Industria. O tratamento de documentação relevante ou a emissão de ordens de pagamento foram algumas das atividades realizadas. Numa vertente mais prática foram levados a cabo procedimentos de controlo de parâmetros de qualidade, nomeadamente a monitorização da temperatura em momentos chave e a estudo de análises químicas realizadas após a recolha do leite. Para estas últimas foi conduzida uma análise estatística dos resultados produzidos ao longo de nove meses para parâmetros como gordura, proteína, extrato seco, células somáticas, contagem microbiana e índice crioscópico. Os resultados indicam a influência do mês de recolha nos valores obtidos para os critérios avaliados, onde a maioria destes sofria um decréscimo nos meses frios. A contagem microbiana e de células somáticas são os valores considerados pela Empresa. O primeiro apresenta-se positivo, não ocorrendo penalizações ao contrário do que acontece no segundo onde a média é a penalização, devendo ser tido em consideração a realização de eventuais procedimentos para localização de eventuais falhas processuais. Este período revelou-se uma etapa de intensa aprendizagem permitindo um maior entendimento do funcionamento do setor de transporte do leite e da importância e vantagens do controlo de parâmetros de qualidade ao longo de todo o processo produtivo.
Milk is a product of high nutritional quality, filling a tangible place in the human diet particularly during childhood. It is constituted mainly by water, yet having a significant content of protein and fat, and the value of these parameters varies considering the producing species. This food product has to reach its consumers in the best salubrity and safety circumstances and should be guaranteed conditions of temperature and performance procedures capable of ensuring such an outcome. The entire production process must be monitored, wherein the realization of this internship focused on the process of milk collection and transportation. At the host institution, Transportes Quintino Augusto Branco & Filhos Lda, various procedures with the ultimate aim of ensuring product quality at the time of delivery to the industry were conducted. The treatment of relevant documentation or issuance of payment orders were some of the activities undertaken. On a more practical component were carried out procedures to control quality parameters’, including temperature monitoring at key moments and the study of chemical analyzes performed after collecting the milk. For the latter was conducted a statistical analysis of the results produced over nine months to parameters such as fat, protein, dry matter, somatic cells, microbial count and cryoscopic index. The results indicate the influence of the month of collection in the values obtained for the evaluated criteria, where most of these suffered a decrease in the cold months. The microbial and somatic cell count are values considered by the Company. The first presents itself positive, does not occur any penalizations unlike the second case where penalization is the average classification should be taken into account performing procedures for locating possible procedural flaws. This period proved to be a stage of intense learning enabling a greater understanding of the functioning of the milk transporting sector and the importance and advantages of the control of quality parameters throughout the entire production process.